A scientific discovery is the outcome of an interesting process of
evolution in the mind of its author.  When we are able to detect the germs
of thought in which such a discovery has originated, and to trace the
successive stages of the reasoning by which the crude idea has developed
into an epoch-making book, we have the materials for reconstructing an
important chapter of scientific history.  Such a contribution to the story
of the "making of science" may be furnished in respect to Darwin's famous
theory of coral-reefs, and the clearly reasoned treatise in which it was
first fully set forth.

The subject of corals and coral-reefs is one concerning which much popular
misconception has always prevailed.  The misleading comparison of coral-rock
with the combs of bees and the nests of wasps is perhaps responsible
for much of this misunderstanding; one writer has indeed described a
coral-reef as being "built by fishes by means of their teeth."  Scarcely
less misleading, however, are the references we so frequently meet with,
both in prose and verse, to the "skill," "industry," and "perseverance" of
the "coral-insect" in "building" his "home."  As well might we praise men
for their cleverness in making their own skeletons, and laud their assiduity
in filling churchyards with the same.  The polyps and other organisms, whose
remains accumulate to form a coral-reef, simply live and perform their
natural functions, and then die, leaving behind them, in the natural course
of events, the hard calcareous portions of their structures to add to the
growing reef.

While the forms of coral-reefs and coral-islands are sometimes very
remarkable and worthy of attentive study, there is no ground, it need
scarcely be added, for the suggestion that they afford proofs of design on
the part of the living builders, or that, in the words of Flinders, they
constitute breastworks, defending the workshops from whence "infant
colonies might be safely sent forth."

It was not till the beginning of the present century that travellers like
Beechey, Chamisso, Quoy and Gaimard, Moresby, Nelson, and others, began to
collect accurate details concerning the forms and structure of coral-masses,
and to make such observations on the habits of reef-forming polyps,
as might serve as a basis for safe reasoning concerning the origin of
coral-reefs and islands.  In the second volume of Lyell's "Principles of
Geology," published in 1832, the final chapter gives an admirable summary
of all that was then known on the subject.  At that time, the ring-form of
the atolls was almost universally regarded as a proof that they had grown
up on submerged volcanic craters; and Lyell gave his powerful support to
that theory.

Charles Darwin was never tired of acknowledging his indebtedness to Lyell.
In dedicating to his friend the second edition of his "Naturalist's Voyage
Round the World," Darwin writes that he does so "with grateful pleasure, as
an acknowledgment that the chief part of whatever scientific merit this
journal and the other works of the author may possess, has been derived
from studying the well-known and admirable 'Principles of Geology.'"

The second volume of Lyell's "Principles" appeared after Darwin had left
England; but it was doubtless sent on to him without delay by his faithful
friend and correspondent, Professor Henslow.  It appears to have reached
Darwin at a most opportune moment, while, in fact, he was studying the
striking evidences of slow and long-continued, but often interrupted
movement on the west coast of South America.  Darwin's acute mind could not
fail to detect the weakness of the then prevalent theory concerning the
origin of the ring-shaped atolls--and the difficulty which he found in
accepting the volcanic theory, as an explanation of the phenomena of
coral-reefs, is well set forth in his book.

In an interesting fragment of autobiography, Darwin has given us a very
clear account of the way in which the leading idea of the theory of
coral-reefs originated in his mind; he writes, "No other work of mine was
begun in so deductive a spirit as this, for the whole theory was thought
out on the west coast of South America, before I had seen a true
coral-reef.  I had therefore only to verify and extend my views by a
careful examination of living reefs.  But it should be observed that I had
during the two previous years been incessantly attending to the effects on
the shores of South America of the intermittent elevation of the land,
together with the denudation and deposition of sediment.  This necessarily
led me to reflect much on the effects of subsidence, and it was easy to
replace in imagination the continued deposition of sediment by the upward
growth of corals.  To do this was to form my theory of the formation of
barrier-reefs and atolls."

On her homeward voyage, the "Beagle" visited Tahiti, Australia, and some of
the coral-islands in the Indian Ocean, and Darwin had an opportunity of
testing and verifying the conclusion at which he had arrived by studying
the statements of other observers.

I well recollect a remarkable conversation I had with Darwin, shortly after
the death of Lyell.  With characteristic modesty, he told me that he never
fully realised the importance of his theory of coral-reefs till he had an
opportunity of discussing it with Lyell, shortly after the return of the
"Beagle".  Lyell, on receiving from the lips of its author a sketch of the
new theory, was so overcome with delight that he danced about and threw
himself into the wildest contortions, as was his manner when excessively
pleased.  He wrote shortly afterwards to Darwin as follows:--"I could think
of nothing for days after your lesson on coral-reefs, but of the tops of
submerged continents.  It is all true, but do not flatter yourself that you
will be believed till you are growing bald like me, with hard work and
vexation at the incredulity of the world."  On May 24th, 1837, Lyell wrote
to Sir John Herschel as follows:--"I am very full of Darwin's new theory of
coral-islands, and have urged Whewell to make him read it at our next
meeting.  I must give up my volcanic crater forever, though it cost me a
pang at first, for it accounted for so much."  Dr. Whewell was president of
the Geological Society at the time, and on May 31st, 1837, Darwin read a
paper entitled "On Certain Areas of Elevation and Subsidence in the Pacific
and Indian oceans, as deduced from the Study of Coral Formations," an
abstract of which appeared in the second volume of the Society's
proceedings.

It was about this time that Darwin, having settled himself in lodgings at
Great Marlborough Street, commenced the writing of his book on "Coral-Reefs."
Many delays from ill-health and the interruption of other work,
caused the progress to be slow, and his journal speaks of "recommencing"
the subject in February 1839, shortly after his marriage, and again in
October of the same year.  In July 1841, he states that he began once more
"after more than thirteen month's interval," and the last proof-sheet of
the book was not corrected till May 6th, 1842.  Darwin writes in his
autobiography, "This book, though a small one, cost me twenty months of
hard work, as I had to read every work on the islands of the Pacific, and
to consult many charts."  The task of elaborating and writing out his books
was, with Darwin, always a very slow and laborious one; but it is clear
that in accomplishing the work now under consideration, there was a long
and constant struggle with the lethargy and weakness resulting from the sad
condition of his health at that time.

Lyell's anticipation that the theory of coral-reefs would be slow in
meeting with general acceptance was certainly not justified by the actual
facts.  On the contrary the new book was at once received with general
assent among both geologists and zoologists, and even attracted a
considerable amount of attention from the general public.

It was not long before the coral-reef theory of Darwin found an able
exponent and sturdy champion in the person of the great American
naturalist, Professor James D. Dana.  Two years after the return of the
"Beagle" to England, the ships of the United States Exploring Expedition
set sail upon their four years' cruise, under the command of Captain
Wilkes, and Dana was a member of the scientific staff.  When, in 1839, the
expedition arrived at Sydney, a newspaper paragraph was found which gave
the American naturalist the first intimation of Darwin's new theory of the
origin of atolls and barrier-reefs.  Writing in 1872, Dana describes the
effect produced on his mind by reading this passage:--"The paragraph threw
a flood of light over the subject, and called forth feelings of peculiar
satisfaction, and of gratefulness to Mr. Darwin, which still come up afresh
whenever the subject of coral islands is mentioned.  The Gambier Islands in
the Paumotus, which gave him the key to the theory, I had not seen; but on
reaching the Feejees, six months later, in 1840, I found there similar
facts on a still grander scale and of a more diversified character, so that
I was afterward enabled to speak of his theory as established with more
positiveness than he himself, in his philosophic caution, had been ready to
adopt.  His work on coral-reefs appeared in 1842, when my report on the
subject was already in manuscript.  It showed that the conclusions on other
points, which we had independently reached, were for the most part the
same.  The principal points of difference relate to the reason for the
absence of corals from some coasts, and the evidence therefrom as to
changes of level, and the distribution of the oceanic regions of elevation
and subsidence--topics which a wide range of travel over the Pacific
brought directly and constantly to my attention."

Among the Reports of the United States Exploring Expedition, two important
works from the pen of Professor Dana made their appearance;--one on
"Zoophytes," which treats at length on "Corals and Coral-Animals," and the
other on "Coral-Reefs and Islands."  In 1872, Dana prepared a work of a
more popular character in which some of the chief results of his studies
are described; it bore the title of "Corals and Coral-Islands."  Of this
work, new and enlarged editions appeared in 1874 and 1890 in America, while
two editions were published in this country in 1872 and 1875.  In all these
works their author, while maintaining an independent judgment on certain
matters of detail, warmly defends the views of Darwin on all points
essential to the theory.

Another able exponent and illustrator of the theory of coral-reefs was
found in Professor J.B. Jukes, who accompanied H.M.S. "Fly", as naturalist,
during the survey of the Great Barrier-Reef--in the years 1842 to 1846.
Jukes, who was a man of great acuteness as well as independence of mind,
concludes his account of the great Australian reefs with the following
words:--"After seeing much of the Great Barrier-Reefs, and reflecting much
upon them, and trying if it were possible by any means to evade the
conclusions to which Mr. Darwin has come, I cannot help adding that his
hypothesis is perfectly satisfactory to my mind, and rises beyond a mere
hypothesis into the true theory of coral-reefs."

As the result of the clear exposition of the subject by Darwin, Lyell,
Dana, and Jukes, the theory of coral-reefs had, by the middle of the
present century, commanded the almost universal assent of both biologists
and geologists.  In 1859 Baron von Richthofen brought forward new facts in
its support, by showing that the existence of the thick masses of dolomitic
limestone in the Tyrol could be best accounted for if they were regarded as
of coralline origin and as being formed during a period of long continued
subsidence.  The same views were maintained by Professor Mojsisovics in his
"Dolomit-riffe von Sudtirol und Venetien," which appeared in 1879.

The first serious note of dissent to the generally accepted theory was
heard in 1863, when a distinguished German naturalist, Dr. Karl Semper,
declared that his study of the Pelew Islands showed that uninterrupted
subsidence could not have been going on in that region.  Dr. Semper's
objections were very carefully considered by Mr. Darwin, and a reply to
them appeared in the second and revised edition of his "Coral-Reefs," which
was published in 1874.  With characteristic frankness and freedom from
prejudice, Darwin admitted that the facts brought forward by Dr. Semper
proved that in certain specified cases, subsidence could not have played
the chief part in originating the peculiar forms of the coral-islands.  But
while making this admission, he firmly maintained that exceptional cases,
like those described in the Pelew Islands, were not sufficient to
invalidate the theory of subsidence as applied to the widely spread atolls,
encircling reefs, and barrier-reefs of the Pacific and Indian Oceans.  It
is worthy of note that to the end of his life Darwin maintained a friendly
correspondence with Semper concerning the points on which they were at
issue.

After the appearance of Semper's work, Dr. J.J. Rein published an account
of the Bermudas, in which he opposed the interpretation of the structure of
the islands given by Nelson and other authors, and maintained that the
facts observed in them are opposed to the views of Darwin.  Although, so
far as I am aware, Darwin had no opportunity of studying and considering
these particular objections, it may be mentioned that two American
geologists have since carefully re-examined the district--Professor W.N.
Rice in 1884 and Professor A. Heilprin in 1889--and they have independently
arrived at the conclusion that Dr. Rein's objections cannot be maintained.

The most serious opposition to Darwin's coral-reef theory, however, was
that which developed itself after the return of H.M.S. "Challenger" from
her famous voyage.  Mr. John Murray, one of the staff of naturalists on
board that vessel, propounded a new theory of coral-reefs, and maintained
that the view that they were formed by subsidence was one that was no
longer tenable; these objections have been supported by Professor Alexander
Agassiz in the United States, and by Dr. A. Geikie, and Dr. H.B. Guppy in
this country.

Although Mr. Darwin did not live to bring out a third edition of his
"Coral-Reefs," I know from several conversations with him that he had given
the most patient and thoughtful consideration to Mr. Murray's paper on the
subject.  He admitted to me that had he known, when he wrote his work, of
the abundant deposition of the remains of calcareous organisms on the sea
floor, he might have regarded this cause as sufficient in a few cases to
raise the summits of submerged volcanoes or other mountains to a level at
which reef-forming corals can commence to flourish.  But he did not think
that the admission that under certain favourable conditions, atolls might
be thus formed without subsidence, necessitated an abandonment of his
theory in the case of the innumerable examples of the kind which stud the
Indian and Pacific Oceans.

A letter written by Darwin to Professor Alexander Agassiz in May 1881 shows
exactly the attitude which careful consideration of the subject led him to
maintain towards the theory propounded by Mr. Murray:--"You will have
seen," he writes, "Mr. Murray's views on the formation of atolls and
barrier-reefs.  Before publishing my book, I thought long over the same
view, but only as far as ordinary marine organisms are concerned, for at
that time little was known of the multitude of minute oceanic organisms.  I
rejected this view, as from the few dredgings made in the "Beagle", in the
south temperate regions, I concluded that shells, the smaller corals, etc.,
decayed and were dissolved when not protected by the deposition of
sediment, and sediment could not accumulate in the open ocean.  Certainly,
shells, etc., were in several cases completely rotten, and crumbled into
mud between my fingers; but you will know whether this is in any degree
common.  I have expressly said that a bank at the proper depth would give
rise to an atoll, which could not be distinguished from one formed during
subsidence.  I can, however, hardly believe in the existence of as many
banks (there having been no subsidence) as there are atolls in the great
oceans, within a reasonable depth, on which minute oceanic organisms could
have accumulated to the depth of many hundred feet."

Darwin's concluding words in the same letter written within a year of his
death, are a striking proof of the candour and openness of mind which he
preserved so well to the end, in this as in other controversies.

"If I am wrong, the sooner I am knocked on the head and annihilated so much
the better.  It still seems to me a marvellous thing that there should not
have been much, and long-continued, subsidence in the beds of the great
oceans.  I wish some doubly rich millionaire would take it into his head to
have borings made in some of the Pacific and Indian atolls, and bring home
cores for slicing from a depth of 500 or 600 feet."

It is noteworthy that the objections to Darwin's theory have for the most
part proceeded from zoologists, while those who have fully appreciated the
geological aspect of the question, have been the staunchest supporters of
the theory of subsidence.  The desirability of such boring operations in
atolls has been insisted upon by several geologists, and it may be hoped
that before many years have passed away, Darwin's hopes may be realised,
either with or without the intervention of the "doubly rich millionaire."

Three years after the death of Darwin, the veteran Professor Dana
re-entered the lists and contributed a powerful defence of the theory of
subsidence in the form of a reply to an essay written by the ablest
exponent of the anti-Darwinian views on this subject, Dr. A. Geikie.  While
pointing out that the Darwinian position had been to a great extent
misunderstood by its opponents, he showed that the rival theory presented
even greater difficulties than those which it professed to remove.

During the last five years, the whole question of the origin of coral-reefs
and islands has been re-opened, and a controversy has arisen, into which,
unfortunately, acrimonious elements have been very unnecessarily
introduced.  Those who desire it, will find clear and impartial statements
of the varied and often mutually destructive views put forward by different
authors, in three works which have made their appearance within the last
year,--"The Bermuda Islands," by Professor Angelo Heilprin; "Corals and
Coral-Islands," new edition by Professor J.D. Dana; and the third edition
of Darwin's "Coral-Reefs," with Notes and Appendix by Professor T.G.
Bonney.

Most readers will, I think, rise from the perusal of these works with the
conviction that, while on certain points of detail it is clear that,
through the want of knowledge concerning the action of marine organisms in
the open ocean, Darwin was betrayed into some grave errors, yet the main
foundations of his argument have not been seriously impaired by the new
facts observed in the deep-sea researches, or by the severe criticism to
which his theory has been subjected during the last ten years.  On the
other hand, I think it will appear that much misapprehension has been
exhibited by some of Darwin's critics, as to what his views and arguments
really were; so that the reprint and wide circulation of the book in its
original form is greatly to be desired, and cannot but be attended with
advantage to all those who will have the fairness to acquaint themselves
with Darwin's views at first hand, before attempting to reply to them.

JOHN W. JUDD.


CORAL-REEFS.

INTRODUCTION.

The object of this volume is to describe from my own observation and the
works of others, the principal kinds of coral-reefs, more especially those
occurring in the open ocean, and to explain the origin of their peculiar
forms.  I do not here treat of the polypifers, which construct these vast
works, except so far as relates to their distribution, and to the
conditions favourable to their vigorous growth.  Without any distinct
intention to classify coral-reefs, most voyagers have spoken of them under
the following heads: "lagoon-islands," or "atolls," "barrier" or
"encircling reefs," and "fringing" or "shore-reefs."  The lagoon-islands
have received much the most attention; and it is not surprising, for every
one must be struck with astonishment, when he first beholds one of these
vast rings of coral-rock, often many leagues in diameter, here and there
surmounted by a low verdant island with dazzling white shores, bathed on
the outside by the foaming breakers of the ocean, and on the inside
surrounding a calm expanse of water, which from reflection, is of a bright
but pale green colour.  The naturalist will feel this astonishment more
deeply after having examined the soft and almost gelatinous bodies of these
apparently insignificant creatures, and when he knows that the solid reef
increases only on the outer edge, which day and night is lashed by the
breakers of an ocean never at rest.  Well did Francois Pyrard de Laval, in
the year 1605, exclaim, "C'est une merueille de voir chacun de ces
atollons, enuironne d'un grand banc de pierre tout autour, n'y ayant point
d'artifice humain."  The accompanying sketch of Whitsunday island, in the
South Pacific, taken from Captain Beechey's admirable "Voyage," although
excellent of its kind, gives but a faint idea of the singular aspect of one
of these lagoon-islands.

(PLATE: UNTITLED WOODCUT, WHITSUNDAY ATOLL.)

Whitsunday Island is of small size, and the whole circle has been converted
into land, which is a comparatively rare circumstance.  As the reef of a
lagoon-island generally supports many separate small islands, the word
"island," applied to the whole, is often the cause of confusion; hence I
have invariably used in this volume the term "atoll," which is the name
given to these circular groups of coral-islets by their inhabitants in the
Indian Ocean, and is synonymous with "lagoon-island."

(PLATE: UNTITLED WOODCUT, REEF AT BOLABOLA ISLAND.)

Barrier-reefs, when encircling small islands, have been comparatively
little noticed by voyagers; but they well deserve attention.  In their
structure they are little less marvellous than atolls, and they give a
singular and most picturesque character to the scenery of the islands they
surround.  In the accompanying sketch, taken from the "Voyage of the
'Coquille'," the reef is seen from within, from one of the high peaks of
the island of Bolabola.  (I have taken the liberty of simplifying the
foreground, and leaving out a mountainous island in the far distance.)
Here, as in Whitsunday Island, the whole of that part of the reef which is
visible is converted into land.  This is a circumstance of rare occurrence;
more usually a snow-white line of great breakers, with here and there an
islet crowned by cocoa-nut trees, separates the smooth waters of the
lagoon-like channel from the waves of the open sea.  The barrier-reefs of
Australia and of New Caledonia, owing to their enormous dimensions, have
excited much attention: in structure and form they resemble those
encircling many of the smaller islands in the Pacific Ocean.

With respect to fringing, or shore-reefs, there is little in their
structure which needs explanation; and their name expresses their
comparatively small extension.  They differ from barrier-reefs in not lying
so far from the shore, and in not having within a broad channel of deep
water.  Reefs also occur around submerged banks of sediment and of worn-down
rock; and others are scattered quite irregularly where the sea is very
shallow; these in most respects are allied to those of the fringing class,
but they are of comparatively little interest.

I have given a separate chapter to each of the above classes, and have
described some one reef or island, on which I possessed most information,
as typical; and have afterwards compared it with others of a like kind.
Although this classification is useful from being obvious, and from
including most of the coral-reefs existing in the open sea, it admits of a
more fundamental division into barrier and atoll-formed reefs on the one
hand, where there is a great apparent difficulty with respect to the
foundation on which they must first have grown; and into fringing-reefs on
the other, where, owing to the nature of the slope of the adjoining land,
there is no such difficulty.  The two blue tints and the red colour
(replaced by numbers in this edition.) on the map (Plate III.), represent
this main division, as explained in the beginning of the last chapter.  In
the Appendix, every existing coral-reef, except some on the coast of Brazil
not included in the map, is briefly described in geographical order, as far
as I possessed information; and any particular spot may be found by
consulting the Index.

Several theories have been advanced to explain the origin of atolls or
lagoon-islands, but scarcely one to account for barrier-reefs.  From the
limited depths at which reef-building polypifers can flourish, taken into
consideration with certain other circumstances, we are compelled to
conclude, as it will be seen, that both in atolls and barrier-reefs, the
foundation on which the coral was primarily attached, has subsided; and
that during this downward movement, the reefs have grown upwards.  This
conclusion, it will be further seen, explains most satisfactorily the
outline and general form of atolls and barrier-reefs, and likewise certain
peculiarities in their structure.  The distribution, also, of the different
kinds of coral-reefs, and their position with relation to the areas of
recent elevation, and to the points subject to volcanic eruptions, fully
accord with this theory of their origin.  (A brief account of my views on
coral formations, now published in my Journal of Researches, was read May
31st, 1837, before the Geological Society, and an abstract has appeared in
the Proceedings.)


(DESCRIPTION OF THE PLATES.

PLATE I.--MAP SHOWING THE RESEMBLANCE IN FORM BETWEEN BARRIER CORAL-REEFS
SURROUNDING MOUNTAINOUS ISLANDS, AND ATOLLS OR LAGOON ISLANDS.)

In the several original surveys, from which the small plans on this plate
have been reduced, the coral-reefs are engraved in very different styles.
For the sake of uniformity, I have adopted the style used in the charts of
the Chagos Archipelago, published by the East Indian Company, from the
survey by Captain Moresby and Lieutenant Powell.  The surface of the reef,
which dries at low water, is represented by a surface with small crosses:
the coral-islets on the reef are marked by small linear spaces, on which a
few cocoa-nut trees, out of all proportion too large, have been introduced
for the sake of clearness.  The entire ANNULAR REEF, which when surrounding
an open expanse of water, forms an "atoll," and when surrounding one or
more high islands, forms an encircling "barrier-reef," has a nearly uniform
structure.  The reefs in some of the original surveys are represented
merely by a single line with crosses, so that their breadth is not given; I
have had such reefs engraved of the width usually attained by coral-reefs.
I have not thought it worth while to introduce all those small and very
numerous reefs, which occur within the lagoons of most atolls and within
the lagoon-channels of most barrier-reefs, and which stand either isolated,
or are attached to the shores of the reef or land.  At Peros Banhos none of
the lagoon-reefs rise to the surface of the water; a few of them have
been introduced, and are marked by plain dotted circles.  A few of the
deepest soundings are laid down within each reef; they are in fathoms, of
six English feet.

Figure 1.--VANIKORO, situated in the western part of the South Pacific;
taken from the survey by Captain D'Urville in the "Astrolabe;" the
soundings on the southern side of the island, namely, from thirty to forty
fathoms, are given from the voyage of the Chev. Dillon; the other soundings
are laid down from the survey by D'Urville; height of the summit of the
island is 3,032 feet.  The principal small detached reefs within the
lagoon-channel have in this instance been represented.  The southern shore
of the island is narrowly fringed by a reef: if the engraver had carried
this reef entirely round both islands, this figure would have served (by
leaving out in imagination the barrier-reef) as a good specimen of an
abruptly-sided island, surrounded by a reef of the fringing class.

Figure 2.--HOGOLEU, or ROUG, in the Caroline Archipelago; taken from the
"Atlas of the Voyage of the 'Astrolabe,'" compiled from the surveys of
Captains Duperrey and D'Urville; the depth of the immense lagoon-like space
within the reef is not known.

Figure 3.--RAIATEA, in the Society Archipelago; from the map given in the
quarto edition of "Cook's First Voyage;" it is probably not accurate.

Figure 4.--BOW, or HEYOU ATOLL (or lagoon-island), in the Low Archipelago,
from the survey by Captain Beechey, R.N.; the lagoon is choked up with
reefs, but the average greatest depth of about twenty fathoms, is given
from the published account of the voyage.

Figure 5.--BOLABOLA, in the Society Archipelago, from the survey of Captain
Duperrey in the "Coquille:" the soundings in this and the following figures
have been altered from French feet to English fathoms; height of highest
point of the island 4,026 feet.

Figure 6.--MAURUA, in the Society Archipelago; from the survey by Captain
Duperrey in the "Coquille:" height of land about eight hundred feet.

Figure 7.--POUYNIPETE, or SENIAVINE, in the Caroline Archipelago; from the
survey by Admiral Lutke.

Figure 8.--GAMBIER ISLANDS, in the southern part of the Low Archipelago;
from the survey by Captain Beechey; height of highest island, 1,246 feet;
the islands are surrounded by extensive and irregular reefs; the reef on
the southern side is submerged.

Figure 9.--PEROS BANHOS ATOLL (or lagoon-island), in the Chagos group in
the Indian Ocean; from the survey by Captain Moresby and Lieutenant Powell;
not nearly all the small submerged reefs in the lagoon are represented; the
annular reef on the southern side is submerged.

Figure 10.--KEELING, or COCOS ATOLL (or lagoon-island), in the Indian
Ocean; from the survey by Captain Fitzroy; the lagoon south of the dotted
line is very shallow, and is left almost bare at low water; the part north
of the line is choked up with irregular reefs.  The annular reef on the
north-west side is broken, and blends into a shoal sandbank, on which the
sea breaks.



CHAPTER I.--ATOLLS OR LAGOON-ISLANDS.

SECTION 1.I.--KEELING ATOLL.

Corals on the outer margin.--Zone of Nulliporae.--Exterior reef.--Islets.--
Coral-conglomerate.--Lagoon.--Calcareous sediment.--Scari and Holuthuriae
subsisting on corals.--Changes in the condition of the reefs and islets.--
Probable subsidence of the atoll.--Future state of the lagoon.

(PLATE: UNTITLED WOODCUT, VERTICAL SECTION THROUGH KEELING ATOLL.)

A.--Level of the sea at low water: where the letter A is placed, the depth
is twenty-five fathoms, and the distance rather more than one hundred and
fifty yards from the edge of the reef.

B.--Outer edge of that flat part of the reef, which dries at low water:
the edge either consists of a convex mound, as represented, or of rugged
points, like those a little farther seaward, beneath the water.

C.--A flat of coral-rock, covered at high water.

D.--A low projecting ledge of brecciated coral-rock washed by the waves at
high water.

E.--A slope of loose fragments, reached by the sea only during gales: the
upper part, which is from six to twelve feet high, is clothed with
vegetation.  The surface of the islet gently slopes to the lagoon.

F.--Level of the lagoon at low water.

KEELING or COCOS atoll is situated in the Indian Ocean, in 12 deg 5' S.,
and longitude 90 deg 55' E.: a reduced chart of it was made from the
survey of Captain Fitzroy and the Officers of H.M.S. "Beagle," is given in
Plate I., Figure 10.  The greatest width of this atoll is nine miles and a
half.  Its structure is in most respects characteristic of the class to
which it belongs, with the exception of the shallowness of the lagoon.  The
accompanying woodcut represents a vertical section, supposed to be drawn at
low water from the outer coast across one of the low islets (one being
taken of average dimensions) to within the lagoon.

The section is true to the scale in a horizontal line, but it could not be
made so in a vertical one, as the average greatest height of the land is
only between six and twelve feet above high-water mark.

I will describe the section, commencing with the outer margin.  I must
first observe that the reef-building polypifers, not being tidal animals,
require to be constantly submerged or washed by the breakers.  I was
assured by Mr. Liesk, a very intelligent resident on these islands, as well
as by some chiefs at Tahiti (Otaheite), that an exposure to the rays of the
sun for a very short time invariably causes their destruction.  Hence it is
possible only under the most favourable circumstances, afforded by an
unusually low tide and smooth water, to reach the outer margin, where the
coral is alive.  I succeeded only twice in gaining this part, and found it
almost entirely composed of a living Porites, which forms great irregularly
rounded masses (like those of an Astraea, but larger) from four to eight
feet broad, and little less in thickness.  These mounds are separated from
each other by narrow crooked channels, about six feet deep, most of which
intersect the line of reef at right angles.  On the furthest mound, which I
was able to reach by the aid of a leaping-pole, and over which the sea
broke with some violence, although the day was quite calm and the tide low,
the polypifers in the uppermost cells were all dead, but between three and
four inches lower down on its side they were living, and formed a
projecting border round the upper and dead surface.  The coral being thus
checked in its upward growth, extends laterally, and hence most of the
masses, especially those a little further inwards, had broad flat dead
summits.  On the other hand I could see, during the recoil of the breakers,
that a few yards further seaward, the whole convex surface of the Porites
was alive; so that the point where we were standing was almost on the exact
upward and shoreward limit of existence of those corals which form the
outer margin of the reef.  We shall presently see that there are other
organic productions, fitted to bear a somewhat longer exposure to the air
and sun.

Next, but much inferior in importance to the Porites, is the Millepora
complanata.  (This Millepora (Palmipora of Blainville), as well as the M.
alcicornis, possesses the singular property of stinging the skin where it
is delicate, as on the face and arm.)

It grows in thick vertical plates, intersecting each other at various
angles, and forms an exceedingly strong honeycombed mass, which generally
affects a circular form, the marginal plates alone being alive.  Between
these plates and in the protected crevices on the reef, a multitude of
branching zoophytes and other productions flourish, but the Porites and
Millepora alone seem able to resist the fury of the breakers on its upper
and outer edge: at the depth of a few fathoms other kinds of stony corals
live.  Mr. Liesk, who was intimately acquainted with every part of this
reef, and likewise with that of North Keeling atoll, assured me that these
corals invariably compose the outer margin.  The lagoon is inhabited by
quite a distinct set of corals, generally brittle and thinly branched; but
a Porites, apparently of the same species with that on the outside, is
found there, although it does not seem to thrive, and certainly does not
attain the thousandth part in bulk of the masses opposed to the breakers.

The woodcut shows the form of the bottom off the reef: the water deepens
for a space between one and two hundred yards wide, very gradually to
twenty-five fathoms (A in section), beyond which the sides plunge into the
unfathomable ocean at an angle of 45 deg.  (The soundings from which this
section is laid down were taken with great care by Captain Fitzroy himself.
He used a bell-shaped lead, having a diameter of four inches, and the
armings each time were cut off and brought on board for me to examine.  The
arming is a preparation of tallow, placed in the concavity at the bottom of
the lead.  Sand, and even small fragments of rock, will adhere to it; and
if the bottom be of rock it brings up an exact impression of its surface.)
To the depth of ten or twelve fathoms the bottom is exceedingly rugged, and
seems formed of great masses of living coral, similar to those on the
margin.  The arming of the lead here invariably came up quite clean, but
deeply indented, and chains and anchors which were lowered, in the hopes of
tearing up the coral, were broken.  Many small fragments, however, of
Millepora alcicornis were brought up; and on the arming from an eight-fathom
cast, there was a perfect impression of an Astraea, apparently
alive.  I examined the rolled fragments cast on the beach during gales, in
order further to ascertain what corals grew outside the reef.  The
fragments consisted of many kinds, of which the Porites already mentioned
and a Madrepora, apparently the M. corymbosa, were the most abundant.  As I
searched in vain in the hollows on the reef and in the lagoon, for a living
specimen of this Madrepore, I conclude that it is confined to a zone
outside, and beneath the surface, where it must be very abundant.
Fragments of the Millepora alcicornis and of an Astraea were also numerous;
the former is found, but not in proportionate numbers, in the hollows on
the reef; but the Astraea I did not see living.  Hence we may infer, that
these are the kinds of coral which form the rugged sloping surface
(represented in the woodcut by an uneven line), round and beneath the
external margin.  Between twelve and twenty fathoms the arming came up an
equal number of times smoothed with sand, and indented with coral: an
anchor and lead were lost at the respective depths of thirteen and sixteen
fathoms.  Out of twenty-five soundings taken at a greater depth than twenty
fathoms, every one showed that the bottom was covered with sand; whereas,
at a less depth than twelve fathoms, every sounding showed that it was
exceedingly rugged, and free from all extraneous particles.  Two soundings
were obtained at the depth of 360 fathoms, and several between two hundred
and three hundred fathoms.  The sand brought up from these depths consisted
of finely triturated fragments of stony zoophytes, but not, as far as I
could distinguish, of a particle of any lamelliform genus: fragments of
shells were rare.

At a distance of 2,200 yards from the breakers, Captain Fitzroy found no
bottom with a line of 7,200 feet in length; hence the submarine slope of
this coral formation is steeper than that of any volcanic cone.  Off the
mouth of the lagoon, and likewise off the northern point of the atoll,
where the currents act violently, the inclination, owing to the
accumulation of sediment, is less.  As the arming of the lead from all the
greater depths showed a smooth sandy bottom, I at first concluded that the
whole consisted of a vast conical pile of calcareous sand, but the sudden
increase of depth at some points, and the circumstance of the line having
been cut, as if rubbed, when between five hundred and six hundred fathoms
were out, indicate the probable existence of submarine cliffs.

On the margin of the reef, close within the line where the upper surface of
the Porites and of the Millepora is dead, three species of Nullipora
flourish.  One grows in thin sheets, like a lichen on old trees; the second
in stony knobs, as thick as a man's finger, radiating from a common centre;
and the third, which is less common, in a moss-like reticulation of thin,
but perfectly rigid branches.  (This last species is of a beautiful bright
peach-blossom colour.  Its branches are about as thick as crow-quills; they
are slightly flattened and knobbed at the extremities.  The extremities
only are alive and brightly coloured.  The two other species are of a dirty
purplish-white.  The second species is extremely hard; its short knob-like
branches are cylindrical, and do not grow thicker at their extremities.)
The three species occur either separately or mingled together; and they
form by their successive growth a layer two or three feet in thickness,
which in some cases is hard, but where formed of the lichen-like kind,
readily yields an impression to the hammer: the surface is of a reddish
colour.  These Nulliporae, although able to exist above the limit of true
corals, seem to require to be bathed during the greater part of each tide
by breaking water, for they are not found in any abundance in the protected
hollows on the back part of the reef, where they might be immersed either
during the whole or an equal proportional time of each tide.  It is
remarkable that organic productions of such extreme simplicity, for the
Nulliporae undoubtedly belong to one of the lowest classes of the vegetable
kingdom, should be limited to a zone so peculiarly circumstanced.  Hence
the layer composed by their growth merely fringes the reef for a space of
about twenty yards in width, either under the form of separate mammillated
projections, where the outer masses of coral are separate, or, more
commonly, where the corals are united into a solid margin, as a continuous
smooth convex mound (B in woodcut), like an artificial breakwater.  Both
the mound and mammillated projections stand about three feet higher than
any other part of the reef, by which term I do not include the islets,
formed by the accumulation of rolled fragments.  We shall hereafter see
that other coral reefs are protected by a similar thick growth of
Nulliporae on the outer margin, the part most exposed to the breakers, and
this must effectually aid in preserving it from being worn down.

The woodcut represents a section across one of the islets on the reef, but
if all that part which is above the level of C were removed, the section
would be that of a simple reef, as it occurs where no islet has been
formed.  It is this reef which essentially forms the atoll.  It is a ring,
enclosing the lagoon on all sides except at the northern end, where there
are two open spaces, through one of which ships can enter.  The reef varies
in width from two hundred and fifty to five hundred yards, its surface is
level, or very slightly inclined towards the lagoon, and at high tide the
sea breaks entirely over it: the water at low tide thrown by the breakers
on the reef, is carried by the many narrow and shoal gullies or channels on
its surface, into the lagoon: a return stream sets out of the lagoon
through the main entrance.  The most frequent coral in the hollows on the
reef is Pocillopora verrucosa, which grows in short sinuous plates, or
branches, and when alive is of a beautiful pale lake-red: a Madrepora,
closely allied or identical with M. pocillifera, is also common.  As soon
as an islet is formed, and the waves are prevented breaking entirely over
the reef, the channels and hollows in it become filled up with cemented
fragments, and its surface is converted into a hard smooth floor (C of
woodcut), like an artificial one of freestone.  This flat surface varies in
width from one hundred to two hundred, or even three hundred yards, and is
strewed with a few large fragments of coral torn up during gales: it is
uncovered only at low water.  I could with difficulty, and only by the aid
of a chisel, procure chips of rock from its surface, and therefore could
not ascertain how much of it is formed by the aggregation of detritus, and
how much by the outward growth of mounds of corals, similar to those now
living on the margin.  Nothing can be more singular than the appearance at
low tide of this "flat" of naked stone, especially where it is externally
bounded by the smooth convex mound of Nulliporae, appearing like a
breakwater built to resist the waves, which are constantly throwing over it
sheets of foaming water.  The characteristic appearance of this "flat" is
shown in the foregoing woodcut of Whitsunday atoll.

The islets on the reef are first formed between two hundred and three
hundred yards from its outer edge, through the accumulation of a pile of
fragments, thrown together by some unusually strong gale.  Their ordinary
width is under a quarter of a mile, and their length varies from a few
yards to several miles.  Those on the south-east and windward side of the
atoll, increase solely by the addition of fragments on their outer side;
hence the loose blocks of coral, of which their surface is composed, as
well as the shells mingled with them, almost exclusively consist of those
kinds which live on the outer coast.  The highest part of the islets
(excepting hillocks of blown sand, some of which are thirty feet high), is
close to the outer beach (E of the woodcut), and averages from six to ten
feet above ordinary high-water mark.  From the outer beach the surface
slopes gently to the shores of the lagoon, which no doubt has been caused
by the breakers the further they have rolled over the reef, having had less
power to throw up fragments.  The little waves of the lagoon heap up sand
and fragments of thinly-branched corals on the inner side of the islets on
the leeward side of the atoll; and these islets are broader than those to
windward, some being even eight hundred yards in width; but the land thus
added is very low.  The fragments beneath the surface are cemented into a
solid mass, which is exposed as a ledge (D of the woodcut), projecting some
yards in front of the outer shore and from two to four feet high.  This
ledge is just reached by the waves at ordinary high-water: it extends in
front of all the islets, and everywhere has a water-worn and scooped
appearance.  The fragments of coral which are occasionally cast on the
"flat" are during gales of unusual violence swept together on the beach,
where the waves each day at high-water tend to remove and gradually wear
them down; but the lower fragments having become firmly cemented together
by the percolation of calcareous matter, resist the daily tides longer, and
hence project as a ledge.  The cemented mass is generally of a white
colour, but in some few parts reddish from ferruginous matter; it is very
hard, and is sonorous under the hammer; it is obscurely divided by seams,
dipping at a small angle seaward; it consists of fragments of the corals
which grow on the outer margin, some quite and others partially rounded,
some small and others between two and three feet across; and of masses of
previously formed conglomerate, torn up, rounded, and re-cemented; or it
consists of a calcareous sandstone, entirely composed of rounded particles,
generally almost blended together, of shells, corals, the spines of echini,
and other such organic bodies; rocks, of this latter kind, occur on many
shores, where there are no coral reefs.  The structure of the coral in the
conglomerate has generally been much obscured by the infiltration of
spathose calcareous matter; and I collected a very interesting series,
beginning with fragments of unaltered coral, and ending with others, where
it was impossible to discover with the naked eye any trace of organic
structure.  In some specimens I was unable, even with the aid of a lens,
and by wetting them, to distinguish the boundaries of the altered coral and
spathose limestone.  Many even of the blocks of coral lying loose on the
beach, had their central parts altered and infiltrated.

The lagoon alone remains to be described; it is much shallower than that of
most atolls of considerable size.  The southern part is almost filled up
with banks of mud and fields of coral, both dead and alive, but there are
considerable spaces, between three and four fathoms, and smaller basins,
from eight to ten fathoms deep.  Probably about half its area consists of
sediment, and half of coral-reefs.  The corals composing these reefs have a
very different aspect from those on the outside; they are very numerous in
kind, and most of them are thinly branched.  Meandrina, however, lives in
the lagoon, and great rounded masses of this coral are numerous, lying
quite or almost loose on the bottom.  The other commonest kinds consist of
three closely allied species of true Madrepora in thin branches; of
Seriatapora subulata; two species of Porites (This Porites has somewhat the
habit of P. clavaria, but the branches are not knobbed at their ends.  When
alive it is of a yellow colour, but after having been washed in fresh water
and placed to dry, a jet-black slimy substance exuded from the entire
surface, so that the specimen now appears as if it had been dipped in ink.)
with cylindrical branches, one of which forms circular clumps, with the
exterior branches only alive; and lastly, a coral something like an
Explanaria, but with stars on both surfaces, growing in thin, brittle,
stony, foliaceous expansions, especially in the deeper basins of the
lagoon.  The reefs on which these corals grow are very irregular in form,
are full of cavities, and have not a solid flat surface of dead rock, like
that surrounding the lagoon; nor can they be nearly so hard, for the
inhabitants made with crowbars a channel of considerable length through
these reefs, in which a schooner, built on the S.E. islet, was floated out.
It is a very interesting circumstance, pointed out to us by Mr. Liesk, that
this channel, although made less than ten years before our visit, was then,
as we saw, almost choked up with living coral, so that fresh excavations
would be absolutely necessary to allow another vessel to pass through it.

The sediment from the deepest parts in the lagoon, when wet, appeared
chalky, but when dry, like very fine sand.  Large soft banks of similar,
but even finer grained mud, occur on the S.E. shore of the lagoon,
affording a thick growth of a Fucus, on which turtle feed: this mud,
although discoloured by vegetable matter, appears from its entire solution
in acids to be purely calcareous.  I have seen in the Museum of the
Geological Society, a similar but more remarkable substance, brought by
Lieutenant Nelson from the reefs of Bermuda, which, when shown to several
experienced geologists, was mistaken by them for true chalk.  On the
outside of the reef much sediment must be formed by the action of the surf
on the rolled fragments of coral; but in the calm waters of the lagoon,
this can take place only in a small degree.  There are, however, other and
unexpected agents at work here: large shoals of two species of Scarus, one
inhabiting the surf outside the reef and the other the lagoon, subsist
entirely, as I was assured by Mr. Liesk, the intelligent resident before
referred to, by browsing on the living polypifers.  I opened several of
these fish, which are very numerous and of considerable size, and I found
their intestines distended by small pieces of coral, and finely ground
calcareous matter.  This must daily pass from them as the finest sediment;
much also must be produced by the infinitely numerous vermiform and
molluscous animals, which make cavities in almost every block of coral.
Dr. J. Allan, of Forres, who has enjoyed the best means of observation,
informs me in a letter that the Holothuriae (a family of Radiata) subsist
on living coral; and the singular structure of bone within the anterior
extremity of their bodies, certainly appears well adapted for this purpose.
The number of the species of Holothuria, and of the individuals which swarm
on every part of these coral-reefs, is extraordinarily great; and many
shiploads are annually freighted, as is well-known, for China with the
trepang, which is a species of this genus.  The amount of coral yearly
consumed, and ground down into the finest mud, by these several creatures,
and probably by many other kinds, must be immense.  These facts are,
however, of more importance in another point of view, as showing us that
there are living checks to the growth of coral-reefs, and that the almost
universal law of "consumed and be consumed," holds good even with the
polypifers forming those massive bulwarks, which are able to withstand the
force of the open ocean.

Considering that Keeling atoll, like other coral formations, has been
entirely formed by the growth of organic beings, and the accumulation of
their detritus, one is naturally led to inquire how long it has continued,
and how long it is likely to continue, in its present state.  Mr. Liesk
informed me that he had seen an old chart in which the present long island
on the S.E. side was divided by several channels into as many islets; and
he assures me that the channels can still be distinguished by the smaller
size of the trees on them.  On several islets, also, I observed that only
young cocoa-nut trees were growing on the extremities; and that older and
taller trees rose in regular succession behind them; which shows that these
islets have very lately increased in length.  In the upper and south-eastern
part of the lagoon, I was much surprised by finding an irregular
field of at least a mile square of branching corals, still upright, but
entirely dead.  They consisted of the species already mentioned; they were
of a brown colour, and so rotten, that in trying to stand on them I sank
halfway up the leg, as if through decayed brushwood.  The tops of the
branches were barely covered by water at the time of lowest tide.  Several
facts having led me to disbelieve in any elevation of the whole atoll, I
was at first unable to imagine what cause could have killed so large a
field of coral.  Upon reflection, however, it appeared to me that the
closing up of the above-mentioned channels would be a sufficient cause; for
before this, a strong breeze by forcing water through them into the head of
the lagoon, would tend to raise its level.  But now this cannot happen, and
the inhabitants observe that the tide rises to a less height, during a high
S.E. wind, at the head than at the mouth of the lagoon.  The corals, which,
under the former condition of things, had attained the utmost possible
limit of upward growth, would thus occasionally be exposed for a short time
to the sun, and be killed.

Besides the increase of dry land, indicated by the foregoing facts, the
exterior solid reef appears to have grown outwards.  On the western side of
the atoll, the "flat" lying between the margin of the reef and the beach,
is very wide; and in front of the regular beach with its conglomerate
basis, there is, in most parts, a bed of sand and loose fragments with
trees growing out of it, which apparently is not reached even by the spray
at high water.  It is evident some change has taken place since the waves
formed the inner beach; that they formerly beat against it with violence
was evident, from a remarkably thick and water-worn point of conglomerate
at one spot, now protected by vegetation and a bank of sand; that they beat
against it in the same peculiar manner in which the swell from windward now
obliquely curls round the margin of the reef, was evident from the
conglomerate having been worn into a point projecting from the beach in a
similarly oblique manner.  This retreat in the line of action of the
breakers might result, either from the surface of the reef in front of the
islets having been submerged at one time, and afterward having grown
upwards, or from the mounds of coral on the margin having continued to grow
outwards.  That an outward growth of this part is in process, can hardly be
doubted from the fact already mentioned of the mounds of Porites with their
summits apparently lately killed, and their sides only three or four inches
lower down thickened by a fresh layer of living coral.  But there is a
difficulty on this supposition which I must not pass over.  If the whole,
or a large part of the "flat," had been formed by the outward growth of the
margin, each successive margin would naturally have been coated by the
Nulliporae, and so much of the surface would have been of equal height with
the existing zone of living Nulliporae: this is not the case, as may be
seen in the woodcut.  It is, however, evident from the abraded state of the
"flat," with its original inequalities filled up, that its surface has been
much modified; and it is possible that the hinder portions of the zone of
Nulliporae, perishing as the reef grows outwards, might be worn down by the
surf.  If this has not taken place, the reef can in no part have increased
outwards in breadth since its formation, or at least since the Nulliporae
formed the convex mound on its margin; for the zone thus formed, and which
stands between two and three feet above the other parts of the reef, is
nowhere much above twenty yards in width.

Thus far we have considered facts, which indicate, with more or less
probability, the increase of the atoll in its different parts: there are
others having an opposite tendency.  On the south-east side, Lieutenant
Sulivan, to whose kindness I am indebted for many interesting observations,
found the conglomerate projecting on the reef nearly fifty yards in front
of the beach: we may infer from what we see in all other parts of the
atoll, that the conglomerate was not originally so much exposed, but formed
the base of an islet, the front and upper part of which has since been
swept away.  The degree to which the conglomerate, round nearly the whole
atoll, has been scooped, broken up, and the fragments cast on the beach, is
certainly very surprising, even on the view that it is the office of
occasional gales to pile up fragments, and of the daily tides to wear them
away.  On the western side, also, of the atoll, where I have described a
bed of sand and fragments with trees growing out of it, in front of an old
beach, it struck both Lieutenant Sulivan and myself, from the manner in
which the trees were being washed down, that the surf had lately
recommenced an attack on this line of coast.  Appearances indicating a
slight encroachment of the water on the land, are plainer within the
lagoon: I noticed in several places, both on its windward and leeward
shores, old cocoa-nut trees falling with their roots undermined, and the
rotten stumps of others on the beach, where the inhabitants assured us the
cocoa-nut could not now grow.  Captain Fitzroy pointed out to me, near the
settlement, the foundation posts of a shed, now washed by every tide, but
which the inhabitants stated, had seven years before stood above high
watermark.  In the calm waters of the lagoon, directly connected with a
great, and therefore stable ocean, it seems very improbable that a change
in the currents, sufficiently great to cause the water to eat into the land
on all sides, should have taken place within a limited period.  From these
considerations I inferred, that probably the atoll had lately subsided to a
small amount; and this inference was strengthened by the circumstance, that
in 1834, two years before our visit, the island had been shaken by a severe
earthquake, and by two slighter ones during the ten previous years.  If,
during these subterranean disturbances, the atoll did subside, the downward
movement must have been very small, as we must conclude from the fields of
dead coral still lipping the surface of the lagoon, and from the breakers
on the western shore not having yet regained the line of their former
action.  The subsidence must, also, have been preceded by a long period of
rest, during which the islets extended to their present size, and the
living margin of the reef grew either upwards, or as I believe outwards, to
its present distance from the beach.

Whether this view be correct or not, the above facts are worthy of
attention, as showing how severe a struggle is in progress on these low
coral formations between the two nicely balanced powers of land and water.
With respect to the future state of Keeling atoll, if left undisturbed, we
can see that the islets may still extend in length; but as they cannot
resist the surf until broken by rolling over a wide space, their increase
in breadth must depend on the increasing breadth of the reef; and this must
be limited by the steepness of the submarine flanks, which can be added to
only by sediment derived from the wear and tear of the coral.  From the
rapid growth of the coral in the channel cut for the schooner, and from the
several agents at work in producing fine sediment, it might be thought that
the lagoon would necessarily become quickly filled up.  Some of this
sediment, however, is transported into the open sea, as appears from the
soundings off the mouth of the lagoon, instead of being deposited within
it.  The deposition, moreover, of sediment, checks the growth of coral-reefs,
so that these two agencies cannot act together with full effect in
filling it up.  We know so little of the habits of the many different
species of corals, which form the lagoon-reefs, that we have no more
reasons for supposing that their whole surface would grow up as quickly as
the coral did in the schooner-channel, than for supposing that the whole
surface of a peat-moss would increase as quickly as parts are known to do
in holes, where the peat has been cut away.  These agencies, nevertheless,
tend to fill up the lagoon; but in proportion as it becomes shallower, so
must the polypifers be subject to many injurious agencies, such as impure
water and loss of food.  For instance, Mr. Liesk informed me, that some
years before our visit unusually heavy rain killed nearly all the fish in
the lagoon, and probably the same cause would likewise injure the corals.
The reefs also, it must be remembered, cannot possibly rise above the level
of the lowest spring-tide, so that the final conversion of the lagoon into
land must be due to the accumulation of sediment; and in the midst of the
clear water of the ocean, and with no surrounding high land, this process
must be exceedingly slow.


SECTION 1.II.--GENERAL DESCRIPTION OF ATOLLS.

General form and size of atolls, their reefs and islets.--External slope.--
Zone of Nulliporae.--Conglomerate.--Depth of lagoons.--Sediment.--Reefs
submerged wholly or in part.--Breaches in the reef.--Ledge-formed shores
round certain lagoons.--Conversion of lagoons into land.

I will here give a sketch of the general form and structure of the many
atolls and atoll-formed reefs which occur in the Pacific and Indian Oceans,
comparing them with Keeling atoll.  The Maldiva atolls and the Great Chagos
Bank differ in so many respects, that I shall devote to them, besides
occasional references, a third section of this chapter.  Keeling atoll may
be considered as of moderate dimensions and of regular form.  Of the
thirty-two islands surveyed by Captain Beechey in the Low Archipelago, the
longest was found to be thirty miles, and the shortest less than a mile;
but Vliegen atoll, situated in another part of the same group, appears to
be sixty miles long and twenty broad.  Most of the atolls in this group are
of an elongated form; thus Bow Island is thirty miles in length, and on an
average only six in width (See Figure 4, Plate I.), and Clermont Tonnere
has nearly the same proportions.  In the Marshall Archipelago (the Ralick
and Radack group of Kotzebue) several of the atolls are more than thirty
miles in length, and Rimsky Korsacoff is fifty-four long, and twenty wide,
at the broadest part of its irregular outline.  Most of the atolls in the
Maldiva Archipelago are of great size, one of them (which, however, bears a
double name) measured in a medial and slightly curved line, is no less than
eighty-eight geographical miles long, its greatest width being under
twenty, and its least only nine and a half miles.  Some atolls have spurs
projecting from them; and in the Marshall group there are atolls united
together by linear reefs, for instance Menchikoff Island (See Figure 3,
Plate II.), which is sixty miles in length, and consists of three loops
tied together.  In far the greater number of cases an atoll consists of a
simple elongated ring, with its outline moderately regular.

The average width of the annular wreath may be taken as about a quarter of
a mile.  Captain Beechey (Beechey's "Voyage to the Pacific and Beering's
Straits," chapter viii.) says that in the atolls of the Low Archipelago it
exceeded in no instance half a mile.  The description given of the
structure and proportional dimensions of the reef and islets of Keeling
atoll, appears to apply perfectly to nearly all the atolls in the Pacific
and Indian Oceans.  The islets are first formed some way back either on the
projecting points of the reef, especially if its form be angular, or on the
sides of the main entrances into the lagoon--that is in both cases, on
points where the breakers can act during gales of wind in somewhat
different directions, so that the matter thrown up from one side may
accumulate against that before thrown up from another.  In Lutke's chart of
the Caroline atolls, we see many instances of the former case; and the
occurrence of islets, as if placed for beacons, on the points where there
is a gateway or breach through the reef, has been noticed by several
authors.  There are some atoll-formed reefs, rising to the surface of the
sea and partly dry at low water, on which from some cause islets have never
been formed; and there are others on which they have been formed, but have
subsequently been worn away.  In atolls of small dimensions the islets
frequently become united into a single horse-shoe or ring-formed strip; but
Diego Garcia, although an atoll of considerable size, being thirteen miles
and a half in length, has its lagoon entirely surrounded, except at the
northern end, by a belt of land, on an average a third of a mile in width.
To show how small the total area of the annular reef and the land is in
islands of this class, I may quote a remark from the voyage of Lutke,
namely, that if the forty-three rings, or atolls, in the Caroline
Archipelago, were put one within another, and over a steeple in the centre
of St. Petersburg, the whole world would not cover that city and its
suburbs.

The form of the bottom off Keeling atoll, which gradually slopes to about
twenty fathoms at the distance of between one and two hundred yards from
the edge of the reef, and then plunges at an angle of 45 deg into
unfathomable depths, is exactly the same (The form of the bottom round the
Marshall atolls in the Northern Pacific is probably similar: Kotzebue
("First Voyage," volume ii., page 16) says: "We had at a small distance
from the reef, forty fathoms depth, which increased a little further so
much that we could find no bottom.") with that of the sections of the
atolls in the Low Archipelago given by Captain Beechey.  The nature,
however, of the bottom seems to differ, for this officer (I must be
permitted to express my obligation to Captain Beechey, for the very kind
manner in which he has given me information on several points, and to own
the great assistance I have derived from his excellent published work.)
informs me that all the soundings, even the deepest, were on coral, but he
does not know whether dead or alive.  The slope round Christmas atoll (Lat.
1 deg 4' N., 157 deg 45' W.), described by Cook (Cook's "Third Voyage,"
volume ii., chapter 10.), is considerably less, at about half a mile from
the edge of the reef, the average depth was about fourteen fathoms on a
fine sandy bottom, and at a mile, only between twenty and forty fathoms.
It has no doubt been owing to this gentle slope, that the strip of land
surrounding its lagoon, has increased in one part to the extraordinary
width of three miles; it is formed of successive ridges of broken shells
and corals, like those on the beach.  I know of no other instance of such
width in the reef of an atoll; but Mr. F.D. Bennett informs me that the
inclination of the bottom round Caroline atoll in the Pacific, is like that
off Christmas Island, very gentle.  Off the Maldiva and Chagos atolls, the
inclination is much more abrupt; thus at Heawandoo Pholo, Lieutenant Powell
(This fact is taken from a MS. account of these groups lent me by Captain
Moresby.  See also Captain Moresby's paper on the Maldiva atolls in the
"Geographical Journal", volume v., page 401.) found fifty and sixty fathoms
close to the edge of the reef, and at 300 yards distance there was no
bottom with a 300-yard line.  Captain Moresby informs me, that at 100
fathoms from the mouth of the lagoon of Diego Garcia, he found no bottom
with 150 fathoms; this is the more remarkable, as the slope is generally
less abrupt in front of channels through a reef, owing to the accumulation
of sediment.  At Egmont Island, also, at 150 fathoms from the reef,
soundings were struck with 150 fathoms.  Lastly, at Cardoo atoll, only
sixty yards from the reef, no bottom was obtained, as I am informed by
Captain Moresby, with a line of 200 fathoms!  The currents run with great
force round these atolls, and where they are strongest, the inclination
appears to be most abrupt.  I am informed by the same authority, that
wherever soundings were obtained off these islands, the bottom was
invariably sandy: nor was there any reason to suspect the existence of
submarine cliffs, as there was at Keeling Island.  (Off some of the islands
in the Low Archipelago the bottom appears to descend by ledges.  Off
Elizabeth Island, which, however, consists of raised coral, Captain Beechey
(page 45, 4to edition) describes three ledges: the first had an easy slope
from the beach to a distance of about fifty yards: the second extended two
hundred yards with twenty-five fathoms on it, and then ended abruptly, like
the first; and immediately beyond this there was no bottom with two hundred
fathoms.)  Here then occurs a difficulty; can sand accumulate on a slope,
which, in some cases, appears to exceed fifty-five degrees?  It must be
observed, that I speak of slopes where soundings were obtained, and not of
such cases, as that of Cardoo, where the nature of the bottom is unknown,
and where its inclination must be nearly vertical.  M. Elie de Beaumont
("Memoires pour servir a une description Geolog. de France," tome iv., page
216.) has argued, and there is no higher authority on this subject, from
the inclination at which snow slides down in avalanches, that a bed of sand
or mud cannot be formed at a greater angle than thirty degrees.
Considering the number of soundings on sand, obtained round the Maldiva and
Chagos atolls, which appears to indicate a greater angle, and the extreme
abruptness of the sand-banks in the West Indies, as will be mentioned in
the Appendix, I must conclude that the adhesive property of wet sand
counteracts its gravity, in a much greater ratio than has been allowed for
by M. Elie de Beaumont.  From the facility with which calcareous sand
becomes agglutinated, it is not necessary to suppose that the bed of loose
sand is thick.

Captain Beechey has observed, that the submarine slope is much less at the
extremities of the more elongated atolls in the Low Archipelago, than at
their sides; in speaking of Ducie's Island he says (Beechey's "Voyage," 4to
edition, page 44.) the buttress, as it may be called, which "has the most
powerful enemy (the S.W. swell) to oppose, is carried out much further, and
with less abruptness than the other."  In some cases, the less inclination
of a certain part of the external slope, for instance of the northern
extremities of the two Keeling atolls, is caused by a prevailing current
which there accumulates a bed of sand.  Where the water is perfectly
tranquil, as within a lagoon, the reefs generally grow up perpendicularly,
and sometimes even overhang their bases; on the other hand, on the leeward
side of Mauritius, where the water is generally tranquil, although not
invariably so, the reef is very gently inclined.  Hence it appears that the
exterior angle varies much; nevertheless in the close similarity in form
between the sections of Keeling atoll and of the atolls in the Low
Archipelago, in the general steepness of the reefs of the Maldiva and
Chagos atolls, and in the perpendicularity of those rising out of water
always tranquil, we may discern the effects of uniform laws; but from the
complex action of the surf and currents, on the growing powers of the coral
and on the deposition of sediment, we can by no means follow out all the
results.

Where islets have been formed on the reef, that part which I have sometimes
called the "flat" and which is partly dry at low water, appears similar in
every atoll.  In the Marshall group in the North Pacific, it may be
inferred from Chamisso's description, that the reef, where islets have not
been formed on it, slopes gently from the external margin to the shores of
the lagoon; Flinders states that the Australian barrier has a similar
inclination inwards, and I have no doubt it is of general occurrence,
although, according to Ehrenberg, the reefs of the Red Sea offer an
exception.  Chamisso observes that "the red colour of the reef (at the
Marshall atolls) under the breakers is caused by a Nullipora, which covers
the stone WHEREVER THE WAVES BEAT; and, under favourable circumstances,
assumes a stalactical form,"--a description perfectly applicable to the
margin of Keeling atoll.  (Kotzebue's "First Voyage," volume iii., page
142.  Near Porto Praya, in the Cape de Verde Islands, some basaltic rocks,
lashed by no inconsiderable surf, were completely enveloped with a layer of
Nulliporae.  The entire surface over many square inches, was coloured of a
peach-blossomed red; the layer, however, was of no greater thickness than
paper.  Another kind, in the form of projecting knobs, grew in the same
situation.  These Nulliporae are closely related to those described on the
coral-reefs, but I believe are of different species.)  Although Chamisso
does not state that the masses of Nulliporae form points or a mound, higher
than the flat, yet I believe that this is the case; for Kotzebue (Kotzebue,
"First Voyage," volume ii., page 16.  Lieutenant Nelson, in his excellent
memoir in the Geological Transactions (volume ii., page 105), alludes to
the rocky points mentioned by Kotzebue, and infers that they consist of
Serpulae, which compose incrusting masses on the reefs of Bermudas, as they
likewise do on a sandstone bar off the coast of Brazil (which I have
described in "London Phil. Journal," October 1841).  These masses of
Serpulae hold the same position, relatively to the action of the sea, with
the Nulliporae on the coral-reefs in the Indian and Pacific Oceans.), in
another part, speaks of the rocks on the edge of the reef "as visible for
about two feet at low water," and these rocks we may feel quite certain are
not formed of true coral (Captain Moresby, in his valuable paper "on the
Northern atolls of Maldivas" ("Geographical Journal", volume v.), says that
the edges of the reefs there stand above water at low spring-tides.)
Whether a smooth convex mound of Nulliporae, like that which appears as if
artificially constructed to protect the margin of Keeling Island, is of
frequent occurrence round atolls, I know not; but we shall presently meet
with it, under precisely the same form, on the outer edge of the
"barrier-reefs" which encircle the Society Islands.

There appears to be scarcely a feature in the structure of Keeling reef,
which is not of common, if not of universal occurrence, in other atolls.
Thus Chamisso describes (Kotzebue's "First Voyage," volume iii., page 144.)
a layer of coarse conglomerate, outside the islets round the Marshall
atolls which "appears on its upper surface uneven and eaten away."  From
drawings, with appended remarks, of Diego Garcia in the Chagos group and of
several of the Maldiva atolls, shown me by Captain Moresby (see also
Moresby on the Northern atolls of the Maldivas, "Geographical Journal",
volume v., page 400.), it is evident that their outer coasts are subject to
the same round of decay and renovation as those of Keeling atoll.  From the
description of the atolls in the Low Archipelago, given in Captain
Beechey's "Voyage," it is not apparent that any conglomerate coral-rock was
there observed.

The lagoon in Keeling atoll is shallow; in the atolls of the Low
Archipelago the depth varies from 20 to 38 fathoms, and in the Marshall
Group, according to Chamisso, from 30 to 35; in the Caroline atolls it is
only a little less.  Within the Maldiva atolls there are large spaces with
45 fathoms, and some soundings are laid down of 49 fathoms.  The greater
part of the bottom in most lagoons, is formed of sediment; large spaces
have exactly the same depth, or the depth varies so insensibly, that it is
evident that no other means, excepting aqueous deposition, could have
leveled the surface so equally.  In the Maldiva atolls this is very
conspicuous, and likewise in some of the Caroline and Marshall Islands.  In
the former large spaces consist of sand and SOFT CLAY; and Kotzebue speaks
of clay having been found within one of the Marshall atolls.  No doubt this
clay is calcareous mud, similar to that at Keeling Island, and to that at
Bermuda already referred to, as undistinguishable from disintegrated chalk,
and which Lieutenant Nelson says is called there pipe-clay.  (I may here
observe that on the coast of Brazil, where there is much coral, the
soundings near the land are described by Admiral Roussin, in the "Pilote du
Bresil", as siliceous sand, mingled with much finely comminuted particles
of shells and coral.  Further in the offing, for a space of 1,300 miles
along the coast, from the Abrolhos Islands to Maranham, the bottom in many
places is composed of "tuf blanc, mele ou forme de madrepores broyes."
This white substance, probably, is analogous to that which occurs within
the above-mentioned lagoons; it is sometimes, according to Roussin, firm,
and he compares it to mortar.)

Where the waves act with unequal force on the two sides of an atoll, the
islets appear to be first formed, and are generally of greater continuity
on the more exposed shore.  The islets, also, which are placed to leeward,
are in most parts of the Pacific liable to be occasionally swept entirely
away by gales, equalling hurricanes in violence, which blow in an opposite
direction to the ordinary trade-wind.  The absence of the islets on the
leeward side of atolls, or when present their lesser dimensions compared
with those to windward, is a comparatively unimportant fact; but in several
instances the reef itself on the leeward side, retaining its usual defined
outline, does not rise to the surface by several fathoms.  This is the case
with the southern side of Peros Banhos (Plate I., Figure 9) in the Chagos
group, with Mourileu atoll (Frederick Lutke's "Voyage autour du Monde,"
volume ii., page 291.  See also his account of Namonouito, below, and the
chart of Oulleay in the Atlas.) in the Caroline Archipelago, and with the
barrier-reef (Plate I., Figure 8) of the Gambier Islands.  I allude to the
latter reef, although belonging to another class, because Captain Beechey
was first led by it to observe the peculiarity in the question.  At Peros
Banhos the submerged part is nine miles in length, and lies at an average
depth of about five fathoms; its surface is nearly level, and consists of
hard stone, with a thin covering of loose sand.  There is scarcely any
living coral on it, even on the outer margin, as I have been particularly
assured by Captain Moresby; it is, in fact, a wall of dead coral-rock,
having the same width and transverse section with the reef in its ordinary
state, of which it is a continuous portion.  The living and perfect parts
terminate abruptly, and abut on the submerged portions, in the same manner
as on the sides of an ordinary passage through the reef.  The reef to
leeward in other cases is nearly or quite obliterated, and one side of the
lagoon is left open; for instance, at Oulleay (Caroline Archipelago), where
a crescent-formed reef is fronted by an irregular bank, on which the other
half of the annular reef probably once stood.  At Namonouito, in the same
Archipelago, both these modifications of the reef concur; it consists of a
great flat bank, with from twenty to twenty-five fathoms water on it; for a
length of more than forty miles on its southern side it is open and without
any reef, whilst on the other sides it is bounded by a reef, in parts
rising to the surface and perfectly characterised, in parts lying some
fathoms submerged.  In the Chagos group there are annular reefs, entirely
submerged, which have the same structure as the submerged and defined
portions just described.  The Speaker's Bank offers an excellent example of
this structure; its central expanse, which is about twenty-two fathoms
deep, is twenty-four miles across; the external rim is of the usual width
of annular reefs, and is well-defined; it lies between six and eight
fathoms beneath the surface, and at the same depth there are scattered
knolls in the lagoon.  Captain Moresby believes the rim consists of dead
rock, thinly covered with sand, and he is certain this is the case with the
external rim of the Great Chagos Bank, which is also essentially a
submerged atoll.  In both these cases, as in the submerged portion of the
reef at Peros Banhos, Captain Moresby feels sure that the quantity of
living coral, even on the outer edge overhanging the deep-sea water, is
quite insignificant.  Lastly, in several parts of the Pacific and Indian
Oceans there are banks, lying at greater depths than in the cases just
mentioned, of the same form and size with the neighbouring atolls, but with
their atoll-like structure wholly obliterated.  It appears from the survey
of Freycinet, that there are banks of this kind in the Caroline
Archipelago, and, as is reported, in the Low Archipelago.  When we discuss
the origin of the different classes of coral formations, we shall see that
the submerged state of the whole of some atoll-formed reefs, and of
portions of others, generally but not invariably on the leeward side, and
the existence of more deeply submerged banks now possessing little or no
signs of their original atoll-like structure, are probably the effects of a
uniform cause,--namely, the death of the coral, during the subsidence of
the area, in which the atolls or banks are situated.

There is seldom, with the exception of the Maldiva atolls, more than two or
three channels, and generally only one leading into the lagoon, of
sufficient depth for a ship to enter.  in small atolls, there is usually
not even one.  Where there is deep water, for instance above twenty
fathoms, in the middle of the lagoon, the channels through the reef are
seldom as deep as the centre,--it may be said that the rim only of the
saucer-shaped hollow forming the lagoon is notched.  Mr. Lyell ("Principles
of Geology," volume iii., page 289.) has observed that the growth of the
coral would tend to obstruct all the channels through a reef, except those
kept open by discharging the water, which during high tide and the greater
part of each ebb is thrown over its circumference.  Several facts indicate
that a considerable quantity of sediment is likewise discharged through
these channels; and Captain Moresby informs me that he has observed, during
the change of the monsoon, the sea discoloured to a distance off the
entrances into the Maldiva and Chagos atolls.  This, probably, would check
the growth of the coral in them, far more effectually than a mere current
of water.  In the many small atolls without any channel, these causes have
not prevented the entire ring attaining the surface.  The channels, like
the submerged and effaced parts of the reef, very generally though not
invariably occur on the leeward side of the atoll, or on that side,
according to Beechey (Beechey's "Voyage," 4to edition, volume i., page
189.), which, from running in the same direction with the prevalent wind,
is not fully exposed to it.  Passages between the islets on the reef,
through which boats can pass at high water, must not be confounded with
ship-channels, by which the annular reef itself is breached.  The passages
between the islets occur, of course, on the windward as well as on the
leeward side; but they are more frequent and broader to leeward, owing to
the lesser dimensions of the islets on that side.

At Keeling atoll the shores of the lagoon shelve gradually, where the
bottom is of sediment, and irregularly or abruptly where there are
coral-reefs; but this is by no means the universal structure in other atolls.
Chamisso (Kotzebue's "First Voyage," volume iii., page 142.), speaking in
general terms of the lagoons in the Marshall atolls, says the lead
generally sinks "from a depth of two or three fathoms to twenty or
twenty-four, and you may pursue a line in which on one side of the boat you
may see the bottom, and on the other the azure-blue deep water."  The shores
of the lagoon-like channel within the barrier-reef at Vanikoro have a similar
structure.  Captain Beechey has described a modification of this structure
(and he believes it is not uncommon) in two atolls in the Low Archipelago,
in which the shores of the lagoon descend by a few, broad, slightly
inclined ledges or steps: thus at Matilda atoll (Beechey's "Voyage," 4to
edition, volume i, page 160.  At Whitsunday Island the bottom of the lagoon
slopes gradually towards the centre, and then deepens suddenly, the edge of
the bank being nearly perpendicular.  This bank is formed of coral and dead
shells.), the great exterior reef, the surface of which is gently inclined
towards and beneath the surface of the lagoon, ends abruptly in a little
cliff three fathoms deep; at its foot, a ledge forty yards wide extends,
shelving gently inwards like the surface-reef, and terminated by a second
little cliff five fathoms deep; beyond this, the bottom of the lagoon
slopes to twenty fathoms, which is the average depth of its centre.  These
ledges seem to be formed of coral-rock; and Captain Beechey says that the
lead often descended several fathoms through holes in them.  In some
atolls, all the coral reefs or knolls in the lagoon come to the surface at
low water; in other cases of rarer occurrence, all lie at nearly the same
depth beneath it, but most frequently they are quite irregular,--some with
perpendicular, some with sloping sides,--some rising to the surface, and
others lying at all intermediate depths from the bottom upwards.  I cannot,
therefore, suppose that the union of such reefs could produce even one
uniformly sloping ledge, and much less two or three, one beneath the other,
and each terminated by an abrupt wall.  At Matilda Island, which offers the
best example of the step-like structure, Captain Beechey observes that the
coral-knolls within the lagoon are quite irregular in their height.  We
shall hereafter see that the theory which accounts for the ordinary form of
atolls, apparently includes this occasional peculiarity in their structure.

In the midst of a group of atolls, there sometimes occur small, flat, very
low islands of coral formation, which probably once included a lagoon,
since filled up with sediment and coral-reefs.  Captain Beechey entertains
no doubt that this has been the case with the two small islands, which
alone of thirty-one surveyed by him in the Low Archipelago, did not contain
lagoons.  Romanzoff Island (in lat. 15 deg S.) is described by Chamisso
(Kotzebue's "First Voyage," volume iii., page 221.) as formed by a dam of
madreporitic rock inclosing a flat space, thinly covered with trees, into
which the sea on the leeward side occasionally breaks.  North Keeling atoll
appears to be in a rather less forward stage of conversion into land; it
consists of a horse-shoe shaped strip of land surrounding a muddy flat, one
mile in its longest axis, which is covered by the sea only at high water.
When describing South Keeling atoll, I endeavoured to show how slow the
final process of filling up a lagoon must be; nevertheless, as all causes
do tend to produce this effect, it is very remarkable that not one
instance, as I believe, is known of a moderately sized lagoon being filled
up even to the low water-line at spring-tides, much less of such a one
being converted into land.  It is, likewise, in some degree remarkable, how
few atolls, except small ones, are surrounded by a single linear strip of
land, formed by the union of separate islets.  We cannot suppose that the
many atolls in the Pacific and Indian Oceans all have had a late origin,
and yet should they remain at their present level, subjected only to the
action of the sea and to the growing powers of the coral, during as many
centuries as must have elapsed since any of the earlier tertiary epochs, it
cannot, I think, be doubted that their lagoons and the islets on their
reef, would present a totally different appearance from what they now do.
This consideration leads to the suspicion that some renovating agency
(namely subsidence) comes into play at intervals, and perpetuates their
original structure.

(DESCRIPTION OF THE PLATES.

PLATE II.--GREAT CHAGOS BANK, NEW CALEDONIA,MENCHIKOFF ATOLL, ETC.

FIGURE 1.--GREAT CHAGOS BANK, in the Indian Ocean; taken from the survey by
Captain Moresby and Lieutenant Powell; the parts which are shaded, with the
exception of two or three islets on the western and northern sides, do not
rise to the surface, but are submerged from four to ten fathoms; the banks
bounded by the dotted lines lie from fifteen to twenty fathoms beneath the
surface, and are formed of sand; the central space is of mud, and from
thirty to fifty fathoms deep.

FIGURE 2.--A vertical section, on the same scale, in an eastern and western
line across the Great Chagos Bank, given for the sake of exhibiting more
clearly its structure.

FIGURE 3.--MENCHIKOFF ATOLL (or lagoon-island), in the Marshall
Archipelago, Northern Pacific Ocean; from Krusenstern's "Atlas of the
Pacific;" originally surveyed by Captain Hagemeister; the depth within the
lagoons is unknown.

FIGURE 4.--MAHLOS MAHDOO ATOLL, together with Horsburgh atoll, in the
Maldiva Archipelago; from the survey by Captain Moresby and Lieutenant
Powell; the white spaces in the middle of the separate small reefs, both on
the margin and in the middle part, are meant to represent little lagoons;
but it was found not possible to distinguish them clearly from the small
islets, which have been formed on these same small reefs; many of the
smaller reefs could not be introduced; the nautical mark (dot over a dash)
over the figures 250 and 200, between Mahlos Mahdoo and Horsburgh atoll and
Powell's island, signifies that soundings were not obtained at these
depths.

FIGURE 5.--NEW CALEDONIA, in the western part of the Pacific; from
Krusenstern's "Atlas," compiled from several surveys; I have slightly
altered the northern point of the reef, in accordance with the "Atlas of
the Voyage of the 'Astrolabe'."  In Krusenstern's "Atlas," the reef is
represented by a single line with crosses; I have for the sake of
uniformity added an interior line.

FIGURE 6.--MALDIVA ARCHIPELAGO, in the Indian Ocean; from the survey by
Captain Moresby and Lieutenant Powell.)


SECTION 1.III.--ATOLLS OF THE MALDIVA ARCHIPELAGO--GREAT CHAGOS BANK.

Maldiva Archipelago.--Ring-formed reefs, marginal and central.--Great
depths in the lagoons of the southern atolls.--Reefs in the lagoons all
rising to the surface.--Position of islets and breaches in the reefs, with
respect to the prevalent winds and action of the waves.--Destruction of
islets.--Connection in the position and submarine foundation of distinct
atolls.--The apparent disseverment of large atolls.--The Great Chagos
Bank.--Its submerged condition and extraordinary structure.

Although occasional references have been made to the Maldiva atolls, and to
the banks in the Chagos group, some points of their structure deserve
further consideration.  My description is derived from an examination of
the admirable charts lately published from the survey of Captain Moresby
and Lieutenant Powell, and more especially from information which Captain
Moresby has communicated to me in the kindest manner.

The Maldiva Archipelago is 470 miles in length, with an average breadth of
about 50 miles.  The form and dimensions of the atolls, and their singular
position in a double line, may be seen, but not well, in the greatly
reduced chart (Figure 6) in Plate II.  The dimensions of the longest atoll
in the group (called by the double name of Milla-dou-Madou and
Tilla-dou-Matte) have already been given; it is 88 miles in a medial and
slightly curved line, and is less than 20 miles in its broadest part.
Suadiva, also, is a noble atoll, being 44 miles across in one direction, and
34 in another, and the great included expanse of water has a depth of between
250 and 300 feet.  The smaller atolls in this group differ in no respect from
ordinary ones; but the larger ones are remarkable from being breached by
numerous deep-water channels leading into the lagoon; for instance, there
are 42 channels, through which a ship could enter the lagoon of Suadiva.
In the three southern large atolls, the separate portions of reef between
these channels have the ordinary structure, and are linear; but in the
other atolls, especially the more northern ones, these portions are ring-
formed, like miniature atolls.  Other ring-formed reefs rise out of the
lagoons, in the place of those irregular ones which ordinarily occur there.
In the reduction of the chart of Mahlos Mahdoo (Plate II., Figure 4), it
was not found easy to define the islets and the little lagoons within each
reef, so that the ring-formed structure is very imperfectly shown; in the
large published charts of Tilla-dou-Matte, the appearance of these rings,
from standing further apart from each other, is very remarkable.  The rings
on the margin are generally elongated; many of them are three, and some
even five miles, in diameter; those within the lagoon are usually smaller,
few being more than two miles across, and the greater number rather less
than one.  The depth of the little lagoon within these small annular reefs
is generally from five to seven fathoms, but occasionally more; and in Ari
atoll many of the central ones are twelve, and some even more than twelve
fathoms deep.  These rings rise abruptly from the platform or bank, on
which they are placed; their outer margin is invariably bordered by living
coral (Captain Moresby informs me that Millepora complanata is one of the
commonest kinds on the outer margin, as it is at Keeling atoll.) within
which there is a flat surface of coral rock; of this flat, sand and
fragments have in many cases accumulated and been converted into islets,
clothed with vegetation.  I can, in fact, point out no essential difference
between these little ring-formed reefs (which, however, are larger, and
contain deeper lagoons than many true atolls that stand in the open sea),
and the most perfectly characterised atolls, excepting that the ring-formed
reefs are based on a shallow foundation, instead of on the floor of the
open sea, and that instead of being scattered irregularly, they are grouped
closely together on one large platform, with the marginal rings arranged in
a rudely formed circle.

The perfect series which can be traced from portions of simple linear reef,
to others including long linear lagoons, and from these again to oval or
almost circular rings, renders it probable that the latter are merely
modifications of the linear or normal state.  It is conformable with this
view, that the ring-formed reefs on the margin, even where most perfect and
standing furthest apart, generally have their longest axes directed in the
line which the reef would have held, if the atoll had been bounded by an
ordinary wall.  We may also infer that the central ring-formed reefs are
modifications of those irregular ones, which are found in the lagoons of
all common atolls.  It appears from the charts on a large scale, that the
ring-like structure is contingent on the marginal channels or breaches
being wide; and, consequently, on the whole interior of the atoll being
freely exposed to the waters of the open sea.  When the channels are narrow
or few in number, although the lagoon be of great size and depth (as in
Suadiva), there are no ring-formed reefs; where the channels are somewhat
broader, the marginal portions of reef, and especially those close to the
larger channels, are ring-formed, but the central ones are not so; where
they are broadest, almost every reef throughout the atoll is more or less
perfectly ring-formed.  Although their presence is thus contingent on the
openness of the marginal channels, the theory of their formation, as we
shall hereafter see, is included in that of the parent atolls, of which
they form the separate portions.

The lagoons of all the atolls in the southern part of the Archipelago are
from ten to twenty fathoms deeper than those in the northern part.  This is
well exemplified in the case of Addoo, the southernmost atoll in the group,
for although only nine miles in its longest diameter, it has a depth of
thirty-nine fathoms, whereas all the other small atolls have comparatively
shallow lagoons; I can assign no adequate cause for this difference in
depth.  In the central and deepest part of the lagoons, the bottom
consists, as I am informed by Captain Moresby, of stiff clay (probably a
calcareous mud); nearer the border it consists of sand, and in the channels
through the reef, of hard sand-banks, sandstone, conglomerate rubble, and a
little live coral.  Close outside the reef and the line joining its
detached portions (where intersected by many channels), the bottom is
sandy, and it slopes abruptly into unfathomable depths.  In most lagoons
the depth is considerably greater in the centre than in the channels; but
in Tilla-dou-Matte, where the marginal ring-formed reefs stand far apart,
the same depth is carried across the entire atoll, from the deep-water line
on one side to that on the other.  I cannot refrain from once again
remarking on the singularity of these atolls,--a great sandy and generally
concave disc rises abruptly from the unfathomable ocean, with its central
expanse studded and its border symmetrically fringed with oval basins of
coral-rock, just lipping the surface of the sea, sometimes clothed with
vegetation, and each containing a little lake of clear water!

In the southern Maldiva atolls, of which there are nine large ones, all the
small reefs within the lagoons come to the surface, and are dry at low
water spring-tides; hence in navigating them, there is no danger from
submarine banks.  This circumstance is very remarkable, as within some
atolls, for instance those of the neighbouring Chagos group, not a single
reef comes to the surface, and in most other cases a few only do, and the
rest lie at all intermediate depths from the bottom upwards.  When treating
of the growth of coral I shall again refer to this subject.

Although in the neighbourhood of the Maldiva Archipelago the winds, during
the monsoons, blow during nearly an equal time from opposite quarters, and
although, as I am informed by Captain Moresby, the westerly winds are the
strongest, yet the islets are almost all placed on the eastern side of the
northern atolls, and on the south-eastern side of the southern atolls.
That the formation of the islets is due to detritus thrown up from the
outside, as in the ordinary manner, and not from the interior of the
lagoons, may, I think be safely inferred from several considerations, which
it is hardly worth while to detail.  As the easterly winds are not the
strongest, their action probably is aided by some prevailing swell or
current.

In groups of atolls, exposed to a trade-wind, the ship-channels into the
lagoons are almost invariably situated on the leeward or less exposed side
of the reef, and the reef itself is sometimes either wanting there, or is
submerged.  A strictly analogous, but different fact, may be observed at
the Maldiva atolls--namely, that where two atolls stand in front of each
other, the breaches in the reef are the most numerous on their near, and
therefore less exposed, sides.  Thus on the near sides of Ari and the two
Nillandoo atolls, which face S. Male, Phaleedoo, and Moloque atolls, there
are seventy-three deep-water channels, and only twenty-five on their outer
sides; on the near side of the three latter named atolls there are fifty-
six openings, and only thirty-seven on their outsides.  It is scarcely
possible to attribute this difference to any other cause than the somewhat
different action of the sea on the two sides, which would ensue from the
protection afforded by the two rows of atolls to each other.  I may here
remark that in most cases, the conditions favourable to the greater
accumulation of fragments on the reef and to its more perfect continuity on
one side of the atoll than on the other, have concurred, but this has not
been the case with the Maldivas; for we have seen that the islets are
placed on the eastern or south-eastern sides, whilst the breaches in the
reef occur indifferently on any side, where protected by an opposite atoll.
The reef being more continuous on the outer and more exposed sides of those
atolls which stand near each other, accords with the fact, that the reef of
the southern atolls is more continuous than that of the northern ones; for
the former, as I am informed by Captain Moresby, are more constantly
exposed than the northern atolls to a heavy surf.

The date of the first formation of some of the islets in this Archipelago
is known to the inhabitants; on the other hand, several islets, and even
some of those which are believed to be very old, are now fast wearing away.
The work of destruction has, in some instances, been completed in ten
years.  Captain Moresby found on one water-washed reef the marks of wells
and graves, which were excavated when it supported an islet.  In South
Nillandoo atoll, the natives say that three of the islets were formerly
larger: in North Nillandoo there is one now being washed away; and in this
latter atoll Lieutenant Prentice found a reef, about six hundred yards in
diameter, which the natives positively affirmed was lately an island
covered with cocoa-nut trees.  It is now only partially dry at low water
spring-tides, and is (in Lieutenant Prentice's words) "entirely covered
with live coral and madrepore."  In the northern part, also, of the Maldiva
Archipelago and in the Chagos group, it is known that some of the islets
are disappearing.  The natives attribute these effects to variations in the
currents of the sea.  For my own part I cannot avoid suspecting that there
must be some further cause, which gives rise to such a cycle of change in
the action of the currents of the great and open ocean.

Several of the atolls in this Archipelago are so related to each other in
form and position, that at the first glance one is led to suspect that they
have originated in the disseverment of a single one.  Male consists of
three perfectly characterised atolls, of which the shape and relative
position are such, that a line drawn closely round all three, gives a
symmetrical figure; to see this clearly, a larger chart is required than
that of the Archipelago in Plate II.; the channel separating the two
northern Male atolls is only little more than a mile wide, and no bottom
was found in it with 100 fathoms.  Powell's Island is situated at the
distance of two miles and a half off the northern end of Mahlos Mahdoo (see
Figure 4, Plate II.), at the exact point where the two sides of the latter,
if prolonged, would meet; no bottom, however, was found in the channel with
200 fathoms; in the wider channel between Horsburgh atoll and the southern
end of Mahlos Mahdoo, no bottom was found with 250 fathoms.  In these and
similar cases, the relation consists only in the form and position of the
atolls.  But in the channel between the two Nillandoo atolls, although
three miles and a quarter wide, soundings were struck at the depth of 200
fathoms; the channel between Ross and Ari atolls is four miles wide, and
only 150 fathoms deep.  Here then we have, besides the relation of form, a
submarine connection.  The fact of soundings having been obtained between
two separate and perfectly characterised atolls is in itself interesting,
as it has never, I believe, been effected in any of the many other groups
of atolls in the Pacific and Indian seas.  In continuing to trace the
connection of adjoining atolls, if a hasty glance be taken at the chart
(Figure 4., Plate II.) of Mahlos Mahdoo, and the line of unfathomable water
be followed, no one will hesitate to consider it as one atoll.  But a
second look will show that it is divided by a bifurcating channel, of which
the northern arm is about one mile and three-quarters in width, with an
average depth of 125 fathoms, and the southern one three-quarters of a mile
wide, and rather less deep.  These channels resemble in the slope of their
sides and general form, those which separate atolls in every respect
distinct; and the northern arm is wider than that dividing two of the Male
atolls.  The ring-formed reefs on the sides of this bifurcating channel are
elongated, so that the northern and southern portions of Mahlos Mahdoo may
claim, as far as their external outline is concerned, to be considered as
distinct and perfect atolls.  But the intermediate portion, lying in the
fork of the channel, is bordered by reefs less perfect than those which
surround any other atoll in the group of equally small dimensions.  Mahlos
Mahdoo, therefore, is in every respect in so intermediate a condition, that
it may be considered either as a single atoll nearly dissevered into three
portions, or as three atolls almost perfect and intimately connected.  This
is an instance of a very early stage of the apparent disseverment of an
atoll, but a still earlier one in many respects is exhibited at Tilla-dou-
Matte.  In one part of this atoll, the ring-formed reefs stand so far apart
from each other, that the inhabitants have given different names to the
northern and southern halves; nearly all the rings, moreover, are so
perfect and stand so separate, and the space from which they rise is so
level and unlike a true lagoon, that we can easily imagine the conversion
of this one great atoll, not into two or three portions, but into a whole
group of miniature atolls.  A perfect series such as we have here traced,
impresses the mind with an idea of actual change; and it will hereafter be
seen, that the theory of subsidence, with the upward growth of the coral,
modified by accidents of probable occurrence, will account for the
occasional disseverment of large atolls.

The Great Chagos bank alone remains to be described.  In the Chagos group
there are some ordinary atolls, some annular reefs rising to the surface
but without any islets on them, and some atoll-formed banks, either quite
submerged, or nearly so.  Of the latter, the Great Chagos Bank is much the
largest, and differs in its structure from the others: a plan of it is
given in Plate II., Figure 1, in which, for the sake of clearness, I have
had the parts under ten fathoms deep finely shaded: an east and west
vertical section is given in Figure 2, in which the vertical scale has been
necessarily exaggerated.  Its longest axis is ninety nautical miles, and
another line drawn at right angles to the first, across the broadest part,
is seventy.  The central part consists of a level muddy flat, between forty
and fifty fathoms deep, which is surrounded on all sides, with the
exception of some breaches, by the steep edges of a set of banks, rudely
arranged in a circle.  These banks consist of sand, with a very little live
coral; they vary in breadth from five to twelve miles, and on an average
lie about sixteen fathoms beneath the surface; they are bordered by the
steep edges of a third narrow and upper bank, which forms the rim to the
whole.  This rim is about a mile in width, and with the exception of two or
three spots where islets have been formed, is submerged between five and
ten fathoms.  It consists of smooth hard rock, covered with a thin layer of
sand, but with scarcely any live coral; it is steep on both sides, and
outwards slopes abruptly into unfathomable depths.  At the distance of less
than half a mile from one part, no bottom was found with 190 fathoms; and
off another point, at a somewhat greater distance, there was none with 210
fathoms.  Small steep-sided banks or knolls, covered with luxuriantly
growing coral, rise from the interior expanse to the same level with the
external rim, which, as we have seen, is formed only of dead rock.  It is
impossible to look at the plan (Figure 1, Plate II.), although reduced to
so small a scale, without at once perceiving that the Great Chagos Bank is,
in the words of Captain Moresby (This officer has had the kindness to lend
me an excellent MS. account of the Chagos Islands; from this paper, from
the published charts, and from verbal information communicated to me by
Captain Moresby, the above account of the Great Chagos Bank is taken.),
"nothing more than a half-drowned atoll."  But of what great dimensions,
and of how extraordinary an internal structure?  We shall hereafter have to
consider both the cause of its submerged condition, a state common to other
banks in the group, and the origin of the singular submarine terraces,
which bound the central expanse: these, I think, it can be shown, have
resulted from a cause analogous to that which has produced the bifurcating
channel across Mahlos Mahdoo.


CHAPTER II.--BARRIER REEFS.

Closely resemble in general form and structure atoll-reefs.--Width and
depth of the lagoon-channels.--Breaches through the reef in front of
valleys, and generally on the leeward side.--Checks to the filling up of
the lagoon-channels.--Size and constitution of the encircled islands.--
Number of islands within the same reef.--Barrier-reefs of New Caledonia and
Australia.--Position of the reef relative to the slope of the adjoining
land.--Probable great thickness of barrier-reefs.

The term "barrier" has been generally applied to that vast reef which
fronts the N.E. shore of Australia, and by most voyagers likewise to that
on the western coast of New Caledonia.  At one time I thought it convenient
thus to restrict the term, but as these reefs are similar in structure, and
in position relatively to the land, to those, which, like a wall with a
deep moat within, encircle many smaller islands, I have classed them
together.  The reef, also, on the west coast of New Caledonia, circling
round the extremities of the island, is an intermediate form between a
small encircling reef and the Australian barrier, which stretches for a
thousand miles in nearly a straight line.

The geographer Balbi has in effect described those barrier-reefs, which
encircle moderately sized islands, by calling them atolls with high land
rising from within their central expanse.  The general resemblance between
the reefs of the barrier and atoll classes may be seen in the small, but
accurately reduced charts on Plate I. (The authorities from which these
charts have been reduced, together with some remarks on them and
descriptive of the Plates, are given separately.), and this resemblance can
be further shown to extend to every part of the structure.  Beginning with
the outside of the reef; many scattered soundings off Gambier, Oualan, and
some other encircled islands, show that close to the breakers there exists
a narrow shelving margin, beyond which the ocean becomes suddenly
unfathomable; but off the west coast of New Caledonia, Captain Kent
(Dalrymple, "Hydrog. Mem." volume iii.) found no bottom with 150 fathoms,
at two ships' length from the reef; so that the slope here must be nearly
as precipitous as off the Maldiva atolls.

I can give little information regarding the kinds of corals which live on
the outer margin.  When I visited the reef at Tahiti, although it was low
water, the surf was too violent for me to see the living masses; but,
according to what I heard from some intelligent native chiefs, they
resemble in their rounded and branchless forms, those on the margin of
Keeling atoll.  The extreme verge of the reef, which was visible between
the breaking waves at low water, consisted of a rounded, convex,
artificial-like breakwater, entirely coated with Nulliporae, and absolutely
similar to that which I have described at Keeling atoll.  From what I heard
when at Tahiti, and from the writings of the Revs. W. Ellis and J.
Williams, I conclude that this peculiar structure is common to most of the
encircled islands of the Society Archipelago.  The reef within this mound
or breakwater, has an extremely irregular surface, even more so than
between the islets on the reef of Keeling atoll, with which alone (as there
are no islets on the reef of Tahiti) it can properly be compared.  At
Tahiti, the reef is very irregular in width; but round many other encircled
islands, for instance, Vanikoro or Gambier Islands (Figures 1 and 8, Plate
I.), it is quite as regular, and of the same average width, as in true
atolls.  Most barrier-reefs on the inner side slope irregularly into the
lagoon-channel (as the space of deep water separating the reef from the
included land may be called), but at Vanikoro the reef slopes only for a
short distance, and then terminates abruptly in a submarine wall, forty
feet high,--a structure absolutely similar to that described by Chamisso in
the Marshall atolls.

In the Society Archipelago, Ellis (Consult, on this and other points, the
"Polynesian Researches," by the Rev. W. Ellis, an admirable work, full of
curious information.) states, that the reefs generally lie at the distance
of from one to one and a half miles, and, occasionally, even at more than
three miles, from the shore.  The central mountains are generally bordered
by a fringe of flat, and often marshy, alluvial land, from one to four
miles in width.  This fringe consists of coral-sand and detritus thrown up
from the lagoon-channel, and of soil washed down from the hills; it is an
encroachment on the channel, analogous to that low and inner part of the
islets in many atolls which is formed by the accumulation of matter from
the lagoon.  At Hogoleu (Figure 2, Plate I.), in the Caroline Archipelago
(See "Hydrographical Mem." and the "Atlas of the Voyage of the
'Astrolabe'," by Captain Dumont D'Urville, page 428.), the reef on the
south side is no less than twenty miles; on the east side, five; and on the
north side, fourteen miles from the encircled high islands.

The lagoon channels may be compared in every respect with true lagoons.  In
some cases they are open, with a level bottom of fine sand; in others they
are choked up with reefs of delicately branched corals, which have the same
general character as those within the Keeling atoll.  These internal reefs
either stand separately, or more commonly skirt the shores of the included
high islands.  The depth of the lagoon-channel round the Society Islands
varies from two or three to thirty fathoms; in Cook's (See the chart in
volume i. of Hawkesworth's 4to edition of "Cook's First Voyage.") chart of
Ulieta, however, there is one sounding laid down of forty-eight fathoms; at
Vanikoro there are several of fifty-four and one of fifty-six and a half
fathoms (English), a depth which even exceeds by a little that of the
interior of the great Maldiva atolls.  Some barrier-reefs have very few
islets on them; whilst others are surmounted by numerous ones; and those
round part of Bolabola (Plate I., Figure 5) form a single linear strip.
The islets first appear either on the angles of the reef, or on the sides
of the breaches through it, and are generally most numerous on the windward
side.  The reef to leeward retaining its usual width, sometimes lies
submerged several fathoms beneath the surface; I have already mentioned
Gambier Island as an instance of this structure.  Submerged reefs, having a
less defined outline, dead, and covered with sand, have been observed (see
Appendix) off some parts of Huaheine and Tahiti.  The reef is more
frequently breached to leeward than to windward; thus I find in
Krusenstern's "Memoir on the Pacific," that there are passages through the
encircling reef on the leeward side of each of the seven Society Islands,
which possess ship-harbours; but that there are openings to windward
through the reef of only three of them.  The breaches in the reef are
seldom as deep as the interior lagoon-like channel; they generally occur in
front of the main valleys, a circumstance which can be accounted for, as
will be seen in the fourth chapter, without much difficulty.  The breaches
being situated in front of the valleys, which descend indifferently on all
sides, explains their more frequent occurrence through the windward side of
barrier-reefs than through the windward side of atolls,--for in atolls
there is no included land to influence the position of the breaches.

It is remarkable, that the lagoon-channels round mountainous islands have
not in every instance been long ago filled up with coral and sediment; but
it is more easily accounted for than appears at first sight.  In cases like
that of Hogoleu and the Gambier Islands, where a few small peaks rise out
of a great lagoon, the conditions scarcely differ from those of an atoll,
and I have already shown, at some length, that the filling up of a true
lagoon must be an extremely slow process.  Where the channel is narrow, the
agency, which on unprotected coasts is most productive of sediment, namely
the force of the breakers, is here entirely excluded, and the reef being
breached in the front of the main valleys, much of the finer mud from the
rivers must be transported into the open sea.  As a current is formed by
the water thrown over the edge of atoll-formed reefs, which carries
sediment with it through the deep-water breaches, the same thing probably
takes place in barrier-reefs, and this would greatly aid in preventing the
lagoon-channel from being filled up.  The low alluvial border, however, at
the foot of the encircled mountains, shows that the work of filling up is
in progress; and at Maura (Plate I., Figure 6), in the Society group, it
has been almost effected, so that there remains only one harbour for small
craft.

If we look at a set of charts of barrier-reefs, and leave out in
imagination the encircled land, we shall find that, besides the many points
already noticed of resemblance, or rather of identity in structure with
atolls, there is a close general agreement in form, average dimensions, and
grouping.  Encircling barrier-reefs, like atolls, are generally elongated,
with an irregularly rounded, though sometimes angular outline.  There are
atolls of all sizes, from less than two miles in diameter to sixty miles
(excluding Tilla-dou-Matte, as it consists of a number of almost
independent atoll-formed reefs); and there are encircling barrier-reefs
from three miles and a half to forty-six miles in diameter,--Turtle Island
being an instance of the former, and Hogoleu of the latter.  At Tahiti the
encircled island is thirty-six miles in its longest axis, whilst at Maurua
it is only a little more than two miles.  It will be shown, in the last
chapter in this volume, that there is the strictest resemblance in the
grouping of atolls and of common islands, and consequently there must be
the same resemblance in the grouping of atolls and of encircling
barrier-reefs.

The islands lying within reefs of this class, are of very various heights.
Tahiti is 7,000 feet (The height of Tahiti is given from Captain Beechey;
Maurua from Mr. F.D. Bennett ("Geograph. Journ." volume viii., page 220);
Aitutaki from measurements made on board the "Beagle"; and Manouai or
Harvey Island, from an estimate by the Rev. J. Williams.  The two latter
islands, however, are not in some respects well characterised examples of
the encircled class.); Maurua about 800; Aitutaki 360, and Manouai only 50.
The geological nature of the included land varies: in most cases it is of
ancient volcanic origin, owing apparently to the fact that islands of this
nature are most frequent within all great seas; some, however, are of
madreporitic limestone, and others of primary formation, of which latter
kind New Caledonia offers the best example.  The central land consists
either of one island, or of several: thus, in the Society group, Eimeo
stands by itself; while Taha and Raiatea (Figure 3, Plate I.), both
moderately large islands of nearly equal size, are included in one reef.
Within the reef of the Gambier group there are four large and some smaller
islands (Figure 8, Plate I.); within that of Hogoleu (Figure 2, Plate I.)
nearly a dozen small islands are scattered over the expanse of one vast
lagoon.

After the details now given, it may be asserted that there is not one point
of essential difference between encircling barrier-reefs and atolls: the
latter enclose a simple sheet of water, the former encircle an expanse with
one or more islands rising from it.  I was much struck with this fact, when
viewing, from the heights of Tahiti, the distant island of Eimeo standing
within smooth water, and encircled by a ring of snow-white breakers.
Remove the central land, and an annular reef like that of an atoll in an
early stage of its formation is left; remove it from Bolabola, and there
remains a circle of linear coral-islets, crowned with tall cocoa-nut trees,
like one of the many atolls scattered over the Pacific and Indian Oceans.

The barrier-reefs of Australia and of New Caledonia deserve a separate
notice from their great dimensions.  The reef on the west coast of New
Caledonia (Figure 5, Plate II.) is 400 miles in length; and for a length of
many leagues it seldom approaches within eight miles of the shore; and near
the southern end of the island, the space between the reef and the land is
sixteen miles in width.  The Australian barrier extends, with a few
interruptions, for nearly a thousand miles; its average distance from the
land is between twenty and thirty miles; and in some parts from fifty to
seventy.  The great arm of the sea thus included, is from ten to twenty-five
fathoms deep, with a sandy bottom; but towards the southern end, where
the reef is further from the shore, the depth gradually increases to forty,
and in some parts to more than sixty fathoms.  Flinders (Flinders' "Voyage
to Terra Australis," volume ii., page 88.) has described the surface of
this reef as consisting of a hard white agglomerate of different kinds of
coral, with rough projecting points.  The outer edge is the highest part;
it is traversed by narrow gullies, and at rare intervals is breached by
ship-channels.  The sea close outside is profoundly deep; but, in front of
the main breaches, soundings can sometimes be obtained.  Some low islets
have been formed on the reef.

(PLATE: UNNAMED, THREE VERTICAL SECTIONS (WOODCUT DIAGRAMS):

1. VANIKORO, from the "Atlas of the Voyage of the 'Astrolabe'," by D.
D'Urville.

2. GAMBIER ISLAND, from Beechey.

3. MAURUA, from the "Atlas of the Voyage of the 'Coquille'," by Duperrey.

The horizontal line is the level of the sea, from which on the right hand a
plummet descends, representing a depth of 200 fathoms, or 1,200 feet.  The
vertical shading shows the section of the land, and the horizontal shading
that of the encircling barrier-reef: from the smallness of the scale, the
lagoon-channel could not be represented.

AA.--Outer edge of the coral-reefs, where the sea breaks.

BB.--The shore of the encircled islands.)

There is one important point in the structure of barrier-reefs which must
here be considered.  The accompanying diagrams represent north and south
vertical sections, taken through the highest points of Vanikoro, Gambier,
and Maurua Islands, and through their encircling reefs.  The scale both in
the horizontal and vertical direction is the same, namely, a quarter of an
inch to a nautical mile.  The height and width of these islands is known;
and I have attempted to represent the form of the land from the shading of
the hills in the large published charts.  It has long been remarked, even
from the time of Dampier, that considerable degree of relation subsists
between the inclination of that part of the land which is beneath water and
that above it; hence the dotted line in the three sections, probably, does
not widely differ in inclination from the actual submarine prolongation of
the land.  If we now look at the outer edge of the reef (AA), and bear in
mind that the plummet on the right hand represents a depth of 1,200 feet,
we must conclude that the vertical thickness of these barrier coral-reefs
is very great.

I must observe that if the sections had been taken in any other direction
across these islands, or across other encircled islands (In the fifth
chapter an east and west section across the Island of Bolabola and its
barrier-reefs is given, for the sake of illustrating another point.  The
unbroken line in it (woodcut No. 5) is the section referred to.  The scale
is .57 of an inch to a mile; it is taken from the "Atlas of the Voyage of
the 'Coquille'," by Duperrey.  The depth of the lagoon-channel is
exaggerated.), the result would have been the same.  In the succeeding
chapter it will be shown that reef-building polypifers cannot flourish at
great depths,--for instance, it is highly improbable that they could exist
at a quarter of the depth represented by the plummet on the right hand of
the woodcut.  Here there is a great APPARENT difficulty--how were the basal
parts of these barrier-reef formed?  It will, perhaps, occur to some, that
the actual reefs formed of coral are not of great thickness, but that
before their first growth, the coasts of these encircled islands were
deeply eaten into, and a broad but shallow submarine ledge thus left, on
the edge of which the coral grew; but if this had been the case, the shore
would have been invariably bounded by lofty cliffs, and not have sloped
down to the lagoon-channel, as it does in many instances.  On this view
(The Rev. D. Tyerman and Mr. Bennett ("Journal of Voyage and Travels,"
volume i., page 215) have briefly suggested this explanation of the origin
of the encircling reefs of the Society Islands.), moreover, the cause of
the reef springing up at such a great distance from the land, leaving a
deep and broad moat within, remains altogether unexplained.  A supposition
of the same nature, and appearing at first more probable is, that the reefs
sprung up from banks of sediment, which had accumulated round the shore
previously to the growth of the coral; but the extension of a bank to the
same distance round an unbroken coast, and in front of those deep arms of
the sea (as in Raiatea, see Plate II., Figure 3) which penetrate nearly to
the heart of some encircled islands, is exceedingly improbable.  And why,
again, should the reef spring up, in some cases steep on both sides like a
wall, at a distance of two, three or more miles from the shore, leaving a
channel often between two hundred and three hundred feet deep, and rising
from a depth which we have reason to believe is destructive to the growth
of coral?  An admission of this nature cannot possibly be made.  The
existence, also, of the deep channel, utterly precludes the idea of the
reef having grown outwards, on a foundation slowly formed on its outside,
by the accumulation of sediment and coral detritus.  Nor, again, can it be
asserted, that the reef-building corals will not grow, excepting at a great
distance from the land; for, as we shall soon see, there is a whole class
of reefs, which take their name from growing closely attached (especially
where the sea is deep) to the beach.  At New Caledonia (see Plate II.,
Figure 5) the reefs which run in front of the west coast are prolonged in
the same line 150 miles beyond the northern extremity of the island, and
this shows that some explanation, quite different from any of those just
suggested, is required.  The continuation of the reefs on each side of the
submarine prolongation of New Caledonia, is an exceedingly interesting
fact, if this part formerly existed as the northern extremity of the
island, and before the attachment of the coral had been worn down by the
action of the sea, or if it originally existed at its present height, with
or without beds of sediment on each flank, how can we possibly account for
the reefs, not growing on the crest of this submarine portion, but fronting
its sides, in the same line with the reefs which front the shores of the
lofty island?  We shall hereafter see, that there is one, and I believe
only one, solution of this difficulty.

One other supposition to account for the position of encircling barrier-reefs
remains, but it is almost too preposterous to be mentioned; namely,
that they rest on enormous submarine craters, surrounding the included
islands.  When the size, height, and form of the islands in the Society
group are considered, together with the fact that all are thus encircled,
such a notion will be rejected by almost every one.  New Caledonia,
moreover, besides its size, is composed of primitive formations, as are
some of the Comoro Islands (I have been informed that this is the case by
Dr. Allan of Forres, who has visited this group.); and Aitutaki consists of
calcareous rock.  We must, therefore, reject these several explanations,
and conclude that the vertical thickness of barrier-reefs, from their outer
edges to the foundation on which they rest (from AA in the section to the
dotted lines) is really great; but in this, there is no difficulty, for it
is not necessary to suppose that the coral has sprung up from an immense
depth, as will be evident when the theory of the upward growth of
coral-reefs, during the slow subsidence of their foundation, is discussed.


CHAPTER III.--FRINGING OR SHORE-REEFS.

Reefs of Mauritius.--Shallow channel within the reef.--Its slow filling
up.--Currents of water formed within it.--Upraised reefs.--Narrow
fringing-reefs in deep seas.--Reefs on the coast of East Africa and of
Brazil.--Fringing-reefs in very shallow seas, round banks of sediment and
on worn-down islands.--Fringing-reefs affected by currents of the sea.--
Coral coating the bottom of the sea, but not forming reefs.

Fringing-reefs, or, as they have been called by some voyagers, shore-reefs,
whether skirting an island or part of a continent, might at first be
thought to differ little, except in generally being of less breadth, from
barrier-reefs.  As far as the superficies of the actual reef is concerned
this is the case; but the absence of an interior deep-water channel, and
the close relation in their horizontal extension with the probable slope
beneath the sea of the adjoining land, present essential points of
difference.

The reefs which fringe the island of Mauritius offer a good example of this
class.  They extend round its whole circumference, with the exception of
two or three parts (This fact is stated on the authority of the Officier du
Roi, in his extremely interesting "Voyage a l'Isle de France," undertaken
in 1768.  According to Captain Carmichael (Hooker's "Bot. Misc." volume
ii., page 316) on one part of the coast there is a space for sixteen miles
without a reef.), where the coast is almost precipitous, and where, if as
is probable the bottom of the sea has a similar inclination, the coral
would have no foundation on which to become attached.  A similar fact may
sometimes be observed even in reefs of the barrier class, which follow much
less closely the outline of the adjoining land; as, for instance, on the
south-east and precipitous side of Tahiti, where the encircling reef is
interrupted.  On the western side of the Mauritius, which was the only part
I visited, the reef generally lies at the distance of about half a mile
from the shore; but in some parts it is distant from one to two, and even
three miles.  But even in this last case, as the coast-land is gently
inclined from the foot of the mountains to the sea-beach, and as the
soundings outside the reef indicate an equally gentle slope beneath the
water, there is no reason for supposing that the basis of the reef, formed
by the prolongation of the strata of the island, lies at a greater depth
than that at which the polypifers could begin constructing the reef.  Some
allowance, however, must be made for the outward extension of the corals on
a foundation of sand and detritus, formed from their own wear, which would
give to the reef a somewhat greater vertical thickness, than would
otherwise be possible.

The outer edge of the reef on the western or leeward side of the island is
tolerably well defined, and is a little higher than any other part.  It
chiefly consists of large strongly branched corals, of the genus Madrepora,
which also form a sloping bed some way out to sea: the kinds of coral
growing in this part will be described in the ensuing chapter.  Between the
outer margin and the beach, there is a flat space with a sandy bottom and a
few tufts of living coral; in some parts it is so shallow, that people, by
avoiding the deeper holes and gullies, can wade across it at low water; in
other parts it is deeper, seldom however exceeding ten or twelve feet, so
that it offers a safe coasting channel for boats.  On the eastern and
windward side of the island, which is exposed to a heavy surf, the reef was
described to me as having a hard smooth surface, very slightly inclined
inwards, just covered at low-water, and traversed by gullies; it appears to
be quite similar in structure to the reefs of the barrier and atoll
classes.

The reef of Mauritius, in front of every river and streamlet, is breached
by a straight passage: at Grand Port, however, there is a channel like
that within a barrier-reef; it extends parallel to the shore for four
miles, and has an average depth of ten or twelve fathoms; its presence may
probably be accounted for by two rivers which enter at each end of the
channel, and bend towards each other.  The fact of reefs of the fringing
class being always breached in front of streams, even of those which are
dry during the greater part of the year, will be explained, when the
conditions unfavourable to the growth of coral are considered.  Low
coral-islets, like those on barrier-reefs and atolls, are seldom formed on
reefs of this class, owing apparently in some cases to their narrowness, and
in others to the gentle slope of the reef outside not yielding many fragments
to the breakers.  On the windward side, however, of the Mauritius, two or
three small islets have been formed.

It appears, as will be shown in the ensuing chapter, that the action of the
surf is favourable to the vigorous growth of the stronger corals, and that
sand or sediment, if agitated by the waves, is injurious to them.  Hence it
is probable that a reef on a shelving shore, like that of Mauritius, would
at first grow up, not attached to the actual beach, but at some little
distance from it; and the corals on the outer margin would be the most
vigorous.  A shallow channel would thus be formed within the reef, and as
the breakers are prevented acting on the shores of the island, and as they
do not ordinarily tear up many fragments from the outside, and as every
streamlet has its bed prolonged in a straight line through the reef, this
channel could be filled up only very slowly with sediment.  But a beach of
sand and of fragments of the smaller kinds of coral seems, in the case of
Mauritius, to be slowly encroaching on the shallow channel.  On many
shelving and sandy coasts, the breakers tend to form a bar of sand a little
way from the beach, with a slight increase of depth within it; for
instance, Captain Grey (Captain Grey's "Journal of Two Expeditions," volume
i. page 369.) states that the west coast of Australia, in latitude 24 deg.,
is fronted by a sand bar about two hundred yards in width, on which there
is only two feet of water; but within it the depth increases to two
fathoms.  Similar bars, more or less perfect, occur on other coasts.  In
these cases I suspect that the shallow channel (which no doubt during
storms is occasionally obliterated) is scooped out by the flowing away of
the water thrown beyond the line, on which the waves break with the
greatest force.  At Pernambuco a bar of hard sandstone (I have described
this singular structure in the "London and Edinburgh Phil. Mag." October
1841.), which has the same external form and height as a coral-reef,
extends nearly parallel to the coast; within this bar currents, apparently
caused by the water thrown over it during the greater part of each tide,
run strongly, and are wearing away its inner wall.  From these facts it can
hardly be doubted, that within most fringing-reefs, especially within those
lying some distance from the land, a return stream must carry away the
water thrown over the outer edge; and the current thus produced, would tend
to prevent the channel being filled up with sediment, and might even deepen
it under certain circumstances.  To this latter belief I am led, by finding
that channels are almost universally present within the fringing-reefs of
those islands which have undergone recent elevatory movements; and this
could hardly have been the case, if the conversion of the very shallow
channel into land had not been counteracted to a certain extent.

A fringing-reef, if elevated in a perfect condition above the level of the
sea, ought to present the singular appearance of a broad dry moat within a
low mound.  The author ("Voyage a l'Isle de France, par un Officier du
Roi," part i., pages 192, 200.) of an interesting pedestrian tour round the
Mauritius, seems to have met with a structure of this kind: he says
"J'observai que la, ou la mer etale, independamment des rescifs du large,
il y a terre UNE ESPECE D'EFFONCEMENT ou chemin couvert naturel.  On y
pourrait mettre du canon," etc.  In another place he adds, "Avant de passer
le Cap, on remarque un gros banc de corail eleve de plus de quinze pieds:
c'est une espece de rescif, que la mer abandonne, il regne au pied une
longue flaque d'eau, dont on pourrait faire un bassin pour de petits
vaisseaux."  But the margin of the reef, although the highest and most
perfect part, from being most exposed to the surf, would generally during a
slow rise of the land be either partially or entirely worn down to that
level, at which corals could renew their growth on its upper edge.  On some
parts of the coast-land of Mauritius there are little hillocks of coral-rock,
which are either the last remnants of a continuous reef, or of low
islets formed on it.  I observed that two such hillocks between Tamarin Bay
and the Great Black River; they were nearly twenty feet high, about two
hundred yards from the present beach, and about thirty feet above its
level.  They rose abruptly from a smooth surface, strewed with worn
fragments of coral.  They consisted in their lower part of hard calcareous
sandstone, and in their upper of great blocks of several species of Astraea
and Madrepora, loosely aggregated; they were divided into irregular beds,
dipping seaward, in one hillock at an angle of 8 deg., and in the other at
18 deg.  I suspect that the superficial parts of the reefs, which have been
upraised together with the islands they fringe, have generally been much
more modified by the wearing action of the sea, than those of Mauritius.

Many islands are fringed by reefs quite similar to those of Mauritius (I
may give Cuba, as another instance; Mr. Taylor ("Loudon's Mag. of Nat.
Hist." volume ix., page 449) has described a reef several miles in length
between Gibara and Vjaro, which extends parallel to the shore at the
distance of between half and the third part of a mile, and encloses a space
of shallow water, with a sandy bottom and tufts of coral.  Outside the edge
of the reef, which is formed of great branching corals, the depth is six
and seven fathoms.  This coast has been upheaved at no very distant
geological period."); but on coasts where the sea deepens very suddenly the
reefs are much narrower, and their limited extension seems evidently to
depend on the high inclination of the submarine slope; a relation, which,
as we have seen, does not exist in reefs of the barrier class.  The
fringing-reefs on steep coasts are frequently not more than from fifty to
one hundred yards in width; they have a nearly smooth, hard surface,
scarcely uncovered at low water, and without any interior shoal channel,
like that within those fringing-reefs, which lie at a greater distance from
the land.  The fragments torn up during gales from the outer margin are
thrown over the reef on the shores of the island.  I may give as instances,
Wateeo, where the reef is described by Cook as being a hundred yards wide;
and Mauti and Elizabeth Islands (Mauti is described by Lord Byron in the
voyage of H.M.S. "Blonde", and Elizabeth Island by Captain Beechey.), where
it is only fifty yards in width: the sea round these islands is very deep.

Fringing-reefs, like barrier-reefs, both surround islands, and front the
shores of continents.  In the charts of the eastern coast of Africa, by
Captain Owen, many extensive fringing-reefs are laid down; thus, for a
space of nearly forty miles, from latitude 1 deg 15' to 1 deg 45' S., a
reef fringes the shore at an average distance of rather more than one mile,
and therefore at a greater distance than is usual in reefs of this class;
but as the coast-land is not lofty, and as the bottom shoals very gradually
(the depth being only from eight to fourteen fathoms at a mile and a half
outside the reef), its extension thus far from the land offers no
difficulty.  The external margin of this reef is described, as formed of
projecting points, within which there is a space, from six to twelve feet
deep, with patches of living coral on it.  At Mukdeesha (latitude 2 deg 1'
N.) "the port is formed," it is said (Owen's "Africa," volume i., page 357,
from which work the foregoing facts are likewise taken.) "by a long reef
extending eastward, four or five miles, within which there is a narrow
channel, with ten to twelve feet of water at low spring-tides;" it lies at
the distance of a quarter of a mile from the shore.  Again, in the plan of
Mombas (latitude 4 deg S.), a reef extends for thirty-six miles, at the
distance of from half a mile to one mile and a quarter from the shore;
within it, there is a channel navigable "for canoes and small craft,"
between six and fifteen feet deep: outside the reef the depth is about
thirty fathoms at the distance of nearly half a mile.  Part of this reef is
very symmetrical, and has a uniform breadth of two hundred yards.

The coast of Brazil is in many parts fringed by reefs.  Of these, some are
not of coral formation; for instance, those near Bahia and in front of
Pernambuco; but a few miles south of this latter city, the reef follows
(See Baron Roussin's "Pilote du Bresil," and accompanying hydrographical
memoir.) so closely every turn of the shore, that I can hardly doubt it is
of coral; it runs at the distance of three-quarters of a mile from the
land, and within it the depth is from ten to fifteen feet.  I was assured
by an intelligent pilot that at Ports Frances and Maceio, the outer part of
the reef consists of living coral, and the inner of a white stone, full of
large irregular cavities, communicating with the sea.  The bottom of the
sea off the coast of Brazil shoals gradually to between thirty and forty
fathoms, at the distance of between nine and ten leagues from the land.

From the description now given, we must conclude that the dimensions and
structure of fringing-reefs depend entirely on the greater or less
inclination of the submarine slope, conjoined with the fact that
reef-building polypifers can exist only at limited depths.  It follows from
this, that where the sea is very shallow, as in the Persian Gulf and in
parts of the East Indian Archipelago, the reefs lose their fringing
character, and appear as separate and irregularly scattered patches, often
of considerable area.  From the more vigorous growth of the coral on the
outside, and from the conditions being less favourable in several respects
within, such reefs are generally higher and more perfect in their marginal
than in their central parts; hence these reefs sometimes assume (and this
circumstance ought not to be overlooked) the appearance of atolls; but they
differ from atolls in their central expanse being much less deep, in their
form being less defined, and in being based on a shallow foundation.  But
when in a deep sea reefs fringe banks of sediment, which have accumulated
beneath the surface, round either islands or submerged rocks, they are
distinguished with difficulty on the one hand from encircling barrier-reefs,
and on the other from atolls.  In the West Indies there are reefs,
which I should probably have arranged under both these classes, had not the
existence of large and level banks, lying a little beneath the surface,
ready to serve as the basis for the attachment of coral, been occasionally
brought into view by the entire or partial absence of reefs on them, and
had not the formation of such banks, through the accumulation of sediment
now in progress, been sufficiently evident.  Fringing-reefs sometimes coat,
and thus protect the foundations of islands, which have been worn down by
the surf to the level of the sea.  According to Ehrenberg, this has been
extensively the case with the islands in the Red Sea, which formerly ranged
parallel to the shores of the mainland, with deep water within them: hence
the reefs now coating their bases are situated relatively to the land like
barrier-reefs, although not belonging to that class; but there are, as I
believe, in the Red Sea some true barrier-reefs.  The reefs of this sea and
of the West Indies will be described in the Appendix.  In some cases,
fringing-reefs appear to be considerably modified in outline by the course
of the prevailing currents.  Dr. J. Allan informs me that on the east coast
of Madagascar almost every headland and low point of sand has a coral-reef
extending from it in a S.W. and N.E. line, parallel to the currents on that
shore.  I should think the influence of the currents chiefly consisted in
causing an extension, in a certain direction, of a proper foundation for
the attachment of the coral.  Round many intertropical islands, for
instance the Abrolhos on the coast of Brazil surveyed by Captain Fitzroy,
and, as I am informed by Mr. Cuming, round the Philippines, the bottom of
the sea is entirely coated by irregular masses of coral, which although
often of large size, do not reach the surface and form proper reefs.  This
must be owing, either to insufficient growth, or to the absence of those
kinds of corals which can withstand the breaking of the waves.

The three classes, atoll-formed, barrier, and fringing-reefs, together with
the modifications just described of the latter, include all the most
remarkable coral formations anywhere existing.  At the commencement of the
last chapter in the volume, where I detail the principles on which the map
(Plate III.) is coloured, the exceptional cases will be enumerated.


CHAPTER IV.--ON THE DISTRIBUTION AND GROWTH OF CORAL-REEFS.

In this chapter I will give all the facts which I have collected, relating
to the distribution of coral-reefs,--to the conditions favourable to their
increase,--to the rate of their growth,--and to the depth at which they are
formed.

These subjects have an important bearing on the theory of the origin of the
different classes of coral-reefs.


SECTION 4.I.--ON THE DISTRIBUTION OF CORAL-REEFS, AND ON THE CONDITIONS
FAVOURABLE TO THEIR INCREASE.

With regard to the limits of latitude, over which coral-reefs extend, I
have nothing new to add.  The Bermuda Islands, in 32 deg 15' N., is the
point furthest removed from the equator, in which they appear to exist; and
it has been suggested that their extension so far northward in this
instance is owing to the warmth of the Gulf Stream.  In the Pacific, the
Loo Choo Islands, in latitude 27 deg N., have reefs on their shores, and
there is an atoll in 28 deg 30', situated N.W. of the Sandwich Archipelago.
In the Red Sea there are coral-reefs in latitude 30 deg.  In the southern
hemisphere coral-reefs do not extend so far from the equatorial sea.  In
the Southern Pacific there are only a few reefs beyond the line of the
tropics, but Houtmans Abrolhos, on the western shores of Australia in
latitude 29 deg S., are of coral formation.

The proximity of volcanic land, owing to the lime generally evolved from
it, has been thought to be favourable to the increase of coral-reefs.
There is, however, not much foundation for this view; for nowhere are
coral-reefs more extensive than on the shores of New Caledonia, and of
north-eastern Australia, which consist of primary formations; and in the
largest groups of atolls, namely the Maldiva, Chagos, Marshall, Gilbert,
and Low Archipelagoes, there is no volcanic or other kind of rock,
excepting that formed of coral.

The entire absence of coral-reefs in certain large areas within the
tropical seas, is a remarkable fact.  Thus no coral-reefs were observed,
during the surveying voyages of the "Beagle" and her tender on the west
coast of South America south of the equator, or round the Galapagos
Islands.  It appears, also, that there are none (I have been informed that
this is the case, by Lieutenant Ryder, R.N., and others who have had ample
opportunities for observation.) north of the equator; Mr. Lloyd, who
surveyed the Isthmus of Panama, remarked to me, that although he had seen
corals living in the Bay of Panama, yet he had never observed any reefs
formed by them.  I at first attributed this absence of reefs on the coasts
of Peru and of the Galapagos Islands (The mean temperature of the surface
sea from observations made by the direction of Captain Fitzroy on the
shores of the Galapagos Islands, between the 16th of September and the 20th
of October, 1835, was 68 deg Fahr.  The lowest temperature observed was
58.5 deg at the south-west end of Albemarle Island; and on the west coast
of this island, it was several times 62 deg and 63 deg.  The mean
temperature of the sea in the Low Archipelago of atolls, and near Tahiti,
from similar observations made on board the "Beagle", was (although further
from the equator) 77.5 deg, the lowest any day being 76.5 deg.  Therefore
we have here a difference of 9.5 deg in mean temperature, and 18 deg in
extremes; a difference doubtless quite sufficient to affect the
distribution of organic beings in the two areas.), to the coldness of the
currents from the south, but the Gulf of Panama is one of the hottest
pelagic districts in the world.  (Humboldt's "Personal Narrative," volume
vii., page 434.)  In the central parts of the Pacific there are islands
entirely free from reefs; in some few of these cases I have thought that
this was owing to recent volcanic action; but the existence of reefs round
the greater part of Hawaii, one of the Sandwich Islands, shows that recent
volcanic action does not necessarily prevent their growth.

In the last chapter I stated that the bottom of the sea round some islands
is thickly coated with living corals, which nevertheless do not form reefs,
either from insufficient growth, or from the species not being adapted to
contend with the breaking waves.

I have been assured by several people, that there are no coral-reefs on the
west coast of Africa (It might be concluded, from a paper by Captain Owen
("Geographical Journal", volume ii., page 89), that the reefs off Cape St.
Anne and the Sherboro' Islands were of coral, although the author states
that they are not purely coralline.  But I have been assured by Lieutenant
Holland, R.N., that these reefs are not of coral, or at least that they do
not at all resemble those in the West Indies.), or round the islands in the
Gulf of Guinea.  This perhaps may be attributed, in part, to the sediment
brought down by the many rivers debouching on that coast, and to the
extensive mud-banks, which line great part of it.  But the islands of St.
Helena, Ascension, the Cape Verdes, St. Paul's, and Fernando Noronha, are,
also, entirely without reefs, although they lie far out at sea, are
composed of the same ancient volcanic rocks, and have the same general
form, with those islands in the Pacific, the shores of which are surrounded
by gigantic walls of coral-rock.  With the exception of Bermuda, there is
not a single coral-reef in the central expanse of the Atlantic Ocean.  It
will, perhaps, be suggested that the quantity of carbonate of lime in
different parts of the sea, may regulate the presence of reefs.  But this
cannot be the case, for at Ascension, the waves charged to excess
precipitate a thick layer of calcareous matter on the tidal rocks; and at
St. Jago, in the Cape Verdes, carbonate of lime not only is abundant on the
shores, but it forms the chief part of some upraised post-tertiary strata.
The apparently capricious distribution, therefore, of coral-reefs, cannot
be explained by any of these obvious causes; but as the study of the
terrestrial and better known half of the world must convince every one that
no station capable of supporting life is lost,--nay more, that there is a
struggle for each station, between the different orders of nature,--we may
conclude that in those parts of the intertropical sea, in which there are
no coral-reefs, there are other organic bodies supplying the place of the
reef-building polypifers.  It has been shown in the chapter on Keeling
atoll that there are some species of large fish, and the whole tribe of
Holothuriae which prey on the tenderer parts of the corals.  On the other
hand, the polypifers in their turn must prey on some other organic beings;
the decrease of which from any cause would cause a proportionate
destruction of the living coral.  The relations, therefore, which determine
the formation of reefs on any shore, by the vigorous growth of the
efficient kinds of coral, must be very complex, and with our imperfect
knowledge quite inexplicable.  From these considerations, we may infer that
changes in the condition of the sea, not obvious to our senses, might
destroy all the coral-reefs in one area, and cause them to appear in
another: thus, the Pacific or Indian Ocean might become as barren of
coral-reefs as the Atlantic now is, without our being able to assign any
adequate cause for such a change.

It has been a question with some naturalists, which part of a reef is most
favourable to the growth of coral.  The great mounds of living Porites and
of Millepora round Keeling atoll occur exclusively on the extreme verge of
the reef, which is washed by a constant succession of breakers; and living
coral nowhere else forms solid masses.  At the Marshall islands the larger
kinds of coral (chiefly species of Astraea, a genus closely allied to
Porites) "which form rocks measuring several fathoms in thickness," prefer,
according to Chamisso (Kotzebue's "First Voyage" (English Translation),
volume iii., pages 142, 143, 331.), the most violent surf.  I have stated
that the outer margin of the Maldiva atolls consists of living corals (some
of which, if not all, are of the same species with those at Keeling atoll),
and here the surf is so tremendous, that even large ships have been thrown,
by a single heave of the sea, high and dry on the reef, all on board thus
escaping with their lives.

Ehrenberg (Ehrenberg, "Uber die Natur und Bildung der Corallen Banke im
rothen Meere," page 49.) remarks, that in the Red Sea the strongest corals
live on the outer reefs, and appear to love the surf; he adds, that the
more branched kinds abound a little way within, but that even these in
still more protected places, become smaller.  Many other facts having a
similar tendency might be adduced.  (In the West Indies, as I am informed
by Captain Bird Allen, R.N., it is the common belief of those, who are best
acquainted with the reefs, that the coral flourishes most, where freely
exposed to the swell of the open sea.)  It has, however, been doubted by
MM. Quoy and Gaimard, whether any kind of coral can even withstand, much
less flourish in, the breakers of an open sea ("Annales des Sciences
Naturelles," tome vi., pages 276, 278.--"La ou les ondes sont agitees, les
Lytophytes ne peuvent travailler, parce qu'elles detruiraient leurs
fragiles edifices," etc.): they affirm that the saxigenous lithophytes
flourish only where the water is tranquil, and the heat intense.  This
statement has passed from one geological work to another; nevertheless, the
protection of the whole reef undoubtedly is due to those kinds of coral,
which cannot exist in the situations thought by these naturalists to be
most favourable to them.  For should the outer and living margin perish, of
any one of the many low coral-islands, round which a line of great breakers
is incessantly foaming, the whole, it is scarcely possible to doubt, would
be washed away and destroyed, in less than half a century.  But the vital
energies of the corals conquer the mechanical power of the waves; and the
large fragments of reef torn up by every storm, are replaced by the slow
but steady growth of the innumerable polypifers, which form the living zone
on its outer edge.

From these facts, it is certain, that the strongest and most massive corals
flourish, where most exposed.  The less perfect state of the reef of most
atolls on the leeward and less exposed side, compared with its state to
windward; and the analogous case of the greater number of breaches on the
near sides of those atolls in the Maldiva Archipelago, which afford some
protection to each other, are obviously explained by this circumstance.  If
the question had been, under what conditions the greater number of species
of coral, not regarding their bulk and strength, were developed, I should
answer,--probably in the situations described by MM. Quoy and Gaimard,
where the water is tranquil and the heat intense.  The total number of
species of coral in the circumtropical seas must be very great: in the Red
Sea alone, 120 kinds, according to Ehrenberg (Ehrenberg, "Uber die Natur,"
etc., etc., page 46.), have been observed.

The same author has observed that the recoil of the sea from a steep shore
is injurious to the growth of coral, although waves breaking over a bank
are not so.  Ehrenberg also states, that where there is much sediment,
placed so as to be liable to be moved by the waves there is little or no
coral; and a collection of living specimens placed by him on a sandy shore
died in the course of a few days.  (Ibid., page 49.)  An experiment,
however, will presently be related in which some large masses of living
coral increased rapidly in size, after having been secured by stakes on a
sandbank.  That loose sediment should be injurious to the living
polypifers, appears, at first sight, probable; and accordingly, in sounding
off Keeling atoll, and (as will hereafter be shown) off Mauritius, the
arming of the lead invariably came up clean, where the coral was growing
vigorously.  This same circumstance has probably given rise to a strange
belief, which, according to Captain Owen (Captain Owen on the Geography of
the Maldiva Islands, "Geographical Journal", volume ii., page 88.), is
general amongst the inhabitants of the Maldiva atolls, namely that corals
have roots, and therefore that if merely broken down to the surface, they
grow up again; but, if rooted out, they are permanently destroyed.  By this
means the inhabitants keep their harbours clear; and thus the French
Governor of St. Mary's in Madagascar, "cleared out and made a beautiful
little port at that place."  For it is probable that sand would accumulate
in the hollows formed by tearing out the corals, but not on the broken and
projecting stumps, and therefore, in the former case, the fresh growth of
the coral might be thus prevented.

In the last chapter I remarked that fringing-reefs are almost universally
breached, where streams enter the sea.  (Lieutenant Wellstead and others
have remarked that this is the case in the Red Sea; Dr. Ruppell ("Reise in
Abyss." Band. i., page 142) says that there are pear-shaped harbours in the
upraised coral-coast, into which periodical streams enter.  From this
circumstance, I presume, we must infer that before the upheaval of the
strata now forming the coast-land, fresh water and sediment entered the sea
at these points; and the coral being thus prevented growing, the pear-shaped
harbours were produced.)  Most authors have attributed this fact to
the injurious effects of the fresh water, even where it enters the sea only
in small quantity, and during a part of the year.  No doubt brackish water
would prevent or retard the growth of coral; but I believe that the mud and
sand which is deposited, even by rivulets when flooded, is a much more
efficient check.  The reef on each side of the channel leading into Port
Louis at Mauritius, ends abruptly in a wall, at the foot of which I sounded
and found a bed of thick mud.  This steepness of the sides appears to be a
general character in such breaches.  Cook (Cook's "First Voyage," volume
ii., page 271 (Hawkesworth's edition).), speaking of one at Raiatea, says,
"like all the rest, it is very steep on both sides."  Now, if it were the
fresh water mingling with the salt which prevented the growth of coral, the
reef certainly would not terminate abruptly, but as the polypifers nearest
the impure stream would grow less vigorously than those farther off, so
would the reef gradually thin away.  On the other hand, the sediment
brought down from the land would only prevent the growth of the coral in
the line of its deposition, but would not check it on the side, so that the
reefs might increase till they overhung the bed of the channel.  The
breaches are much fewer in number, and front only the larger valleys in
reefs of the encircling barrier class.  They probably are kept open in the
same manner as those into the lagoon of an atoll, namely, by the force of
the currents and the drifting outwards of fine sediment.  Their position in
front of valleys, although often separated from the land by deep water
lagoon-channels, which it might be thought would entirely remove the
injurious effects both of the fresh water and the sediment, will receive a
simple explanation when we discuss the origin of barrier-reefs.

In the vegetable kingdom every different station has its peculiar group of
plants, and similar relations appear to prevail with corals.  We have
already described the great difference between the corals within the lagoon
of an atoll and those on its outer margin.  The corals, also, on the margin
of Keeling Island occurred in zones; thus the Porites and Millepora
complanata grow to a large size only where they are washed by a heavy sea,
and are killed by a short exposure to the air; whereas, three species of
Nullipora also live amidst the breakers, but are able to survive uncovered
for a part of each tide; at greater depths, a strong Madrepora and
Millepora alcicornis are the commonest kinds, the former appearing to be
confined to this part, beneath the zone of massive corals, minute
encrusting corallines and other organic bodies live.  If we compare the
external margin of the reef at Keeling atoll with that on the leeward side
of Mauritius, which are very differently circumstanced, we shall find a
corresponding difference in the appearance of the corals.  At the latter
place, the genus Madrepora is preponderant over every other kind, and
beneath the zone of massive corals there are large beds of Seriatopora.
There is also a marked difference, according to Captain Moresby (Captain
Moresby on the Northern Maldiva atolls, "Geographical Journal", volume v.,
page 401.), between the great branching corals of the Red Sea, and those on
the reefs of the Maldiva atolls.

These facts, which in themselves are deserving of notice, bear, perhaps,
not very remotely, on a remarkable circumstance which has been pointed out
to me by Captain Moresby, namely, that with very few exceptions, none of
the coral-knolls within the lagoons of Peros Banhos, Diego Garcia, and the
Great Chagos Bank (all situated in the Chagos group), rise to the surface
of the water; whereas all those, with equally few exceptions, within
Solomon and Egmont atolls in the same group, and likewise within the large
southern Maldiva atolls, reach the surface.  I make these statements, after
having examined the charts of each atoll.  In the lagoon of Peros Banhos,
which is nearly twenty miles across, there is only one single reef which
rises to the surface; in Diego Garcia there are seven, but several of these
lie close to the margin of the lagoon, and need scarcely have been
reckoned; in the Great Chagos Bank there is not one.  On the other hand, in
the lagoons of some of the great southern Maldiva atolls, although thickly
studded with reefs, every one without exception rises to the surface; and
on an average there are less than two submerged reefs in each atoll; in the
northern atolls, however, the submerged lagoon-reefs are not quite so rare.
The submerged reefs in the Chagos atolls generally have from one to seven
fathoms water on them, but some have from seven to ten.  Most of them are
small with very steep sides (Some of these statements were not communicated
to me verbally by Captain Moresby, but are taken from the MS. account
before alluded to, of the Chagos Group.); at Peros Banhos they rise from a
depth of about thirty fathoms, and some of them in the Great Chagos Bank
from above forty fathoms; they are covered, Captain Moresby informs me,
with living and healthy coral, two and three feet high, consisting of
several species.  Why then have not these lagoon-reefs reached the surface,
like the innumerable ones in the atolls above named?  If we attempt to
assign any difference in their external conditions, as the cause of this
diversity, we are at once baffled.  The lagoon of Diego Garcia is not deep,
and is almost wholly surrounded by its reef; Peros Banhos is very deep,
much larger, with many wide passages communicating with the open sea.  On
the other hand, of those atolls, in which all or nearly all the lagoon-reefs
have reached the surface, some are small, others large, some shallow,
others deep, some well-enclosed, and others open.

Captain Moresby informs me that he has seen a French chart of Diego Garcia
made eighty years before his survey, and apparently very accurate; and from
it he infers, that during this interval there has not been the smallest
change in the depth on any of the knolls within the lagoon.  It is also
known that during the last fifty-one years, the eastern channel into the
lagoon has neither become narrower, nor decreased in depth; and as there
are numerous small knolls of living coral within it, some change might have
been anticipated.  Moreover, as the whole reef round the lagoon of this
atoll has been converted into land--an unparalleled case, I believe, in an
atoll of such large size,--and as the strip of land is for considerable
spaces more than half a mile wide--also a very unusual circumstance,--we
have the best possible evidence, that Diego Garcia has remained at its
present level for a very long period.  With this fact, and with the
knowledge that no sensible change has taken place during eighty years in
the coral-knolls, and considering that every single reef has reached the
surface in other atolls, which do not present the smallest appearance of
being older than Diego Garcia and Peros Banhos, and which are placed under
the same external conditions with them, one is led to conclude that these
submerged reefs, although covered with luxuriant coral, have no tendency to
grow upwards, and that they would remain at their present levels for an
almost indefinite period.

From the number of these knolls, from their position, size, and form, many
of them being only one or two hundred yards across, with a rounded outline,
and precipitous sides,--it is indisputable that they have been formed by
the growth of coral; and this makes the case much more remarkable.  In
Peros Banhos and in the Great Chagos Bank, some of these almost columnar
masses are 200 feet high, and their summits lie only from two to eight
fathoms beneath the surface; therefore, a small proportional amount more of
growth would cause them to attain the surface, like those numerous knolls,
which rise from an equally great depth within the Maldiva atolls.  We can
hardly suppose that time has been wanting for the upward growth of the
coral, whilst in Diego Garcia, the broad annular strip of land, formed by
the continued accumulation of detritus, shows how long this atoll has
remained at its present level.  We must look to some other cause than the
rate of growth; and I suspect it will be found in the reefs being formed of
different species of corals, adapted to live at different depths.

The Great Chagos Bank is situated in the centre of the Chagos Group, and
the Pitt and Speaker Banks at its two extreme points.  These banks resemble
atolls, except in their external rim being about eight fathoms submerged,
and in being formed of dead rock, with very little living coral on it: a
portion nine miles long of the annular reef of Peros Banhos atoll is in the
same condition.  These facts, as will hereafter be shown, render it very
probable that the whole group at some former period subsided seven or eight
fathoms; and that the coral perished on the outer margin of those atolls
which are now submerged, but that it continued alive, and grew up to the
surface on those which are now perfect.  If these atolls did subside, and
if from the suddenness of the movement or from any other cause, those
corals which are better adapted to live at a certain depth than at the
surface, once got possession of the knolls, supplanting the former
occupants, they would exert little or no tendency to grow upwards.  To
illustrate this, I may observe, that if the corals of the upper zone on the
outer edge of Keeling atoll were to perish, it is improbable that those of
the lower zone would grow to the surface, and thus become exposed to
conditions for which they do not appear to be adapted.  The conjecture,
that the corals on the submerged knolls within the Chagos atolls have
analogous habits with those of the lower zone outside Keeling atoll,
receives some support from a remark by Captain Moresby, namely, that they
have a different appearance from those on the reefs in the Maldiva atolls,
which, as we have seen, all rise to the surface: he compares the kind of
difference to that of the vegetation under different climates.  I have
entered at considerable length into this case, although unable to throw
much light on it, in order to show that an equal tendency to upward growth
ought not to be attributed to all coral-reefs,--to those situated at
different depths,--to those forming the ring of an atoll or those on the
knolls within a lagoon,--to those in one area and those in another.  The
inference, therefore, that one reef could not grow up to the surface within
a given time, because another, not known to be covered with the same
species of corals, and not known to be placed under conditions exactly the
same, has not within the same time reached the surface, is unsound.


SECTION 4.II.--ON THE RATE OF GROWTH OF CORAL-REEFS.

The remark made at the close of the last section, naturally leads to this
division of our subject, which has not, I think, hitherto been considered
under a right point of view.  Ehrenberg (Ehrenberg, as before cited, pages
39, 46, and 50.) has stated, that in the Red Sea, the corals only coat
other rocks in a layer from one to two feet in thickness, or at most to a
fathom and a half; and he disbelieves that, in any case, they form, by
their own proper growth, great masses, stratum over stratum.  A nearly
similar observation has been made by MM. Quoy and Gaimard ("Annales des
Sciences Nat." tom. vi., page 28.), with respect to the thickness of some
upraised beds of coral, which they examined at Timor and some other places.
Ehrenberg (Ehrenberg, ut sup., page 42.) saw certain large massive corals
in the Red Sea, which he imagines to be of such vast antiquity, that they
might have been beheld by Pharaoh; and according to Mr. Lyell (Lyell's
"Principles of Geology," book iii., chapter xviii.) there are certain
corals at Bermuda, which are known by tradition, to have been living for
centuries.  To show how slowly coral-reefs grow upwards, Captain Beechey
(Beechey's "Voyage to the Pacific," chapter viii.) has adduced the case of
the Dolphin Reef off Tahiti, which has remained at the same depth beneath
the surface, namely about two fathoms and a half, for a period of
sixty-seven years.  There are reefs in the Red Sea, which certainly do not
appear (Ehrenberg, ut sup., page 43.) to have increased in dimensions during
the last half-century, and from the comparison of old charts with recent
surveys, probably not during the last two hundred years.  These, and other
similar facts, have so strongly impressed many with the belief of the
extreme slowness of the growth of corals, that they have even doubted the
possibility of islands in the great oceans having been formed by their
agency.  Others, again, who have not been overwhelmed by this difficulty,
have admitted that it would require thousands, and tens of thousands of
years, to form a mass, even of inconsiderable thickness; but the subject
has not, I believe, been viewed in the proper light.

That masses of considerable thickness have been formed by the growth of
coral, may be inferred with certainty from the following facts.  In the
deep lagoons of Peros Banhos and of the Great Chagos Bank, there are, as
already described, small steep-sided knolls covered with living coral.
There are similar knolls in the southern Maldiva atolls, some of which, as
Captain Moresby assures me, are less than a hundred yards in diameter, and
rise to the surface from a depth of between two hundred and fifty and three
hundred feet.  Considering their number, form, and position, it would be
preposterous to suppose that they are based on pinnacles of any rock, not
of coral formation; or that sediment could have been heaped up into such
small and steep isolated cones.  As no kind of living coral grows above the
height of a few feet, we are compelled to suppose that these knolls have
been formed by the successive growth and death of many individuals,--first
one being broken off or killed by some accident, and then another, and one
set of species being replaced by another set with different habits, as the
reef rose nearer the surface, or as other changes supervened.  The spaces
between the corals would become filled up with fragments and sand, and such
matter would probably soon be consolidated, for we learn from Lieutenant
Nelson ("Geological Transactions," volume v., page 113.), that at Bermuda a
process of this kind takes place beneath water, without the aid of
evaporation.  In reefs, also, of the barrier class, we may feel sure, as I
have shown, that masses of great thickness have been formed by the growth
of the coral; in the case of Vanikoro, judging only from the depth of the
moat between the land and the reef, the wall of coral-rock must be at least
three hundred feet in vertical thickness.

It is unfortunate that the upraised coral-islands in the Pacific have not
been examined by a geologist.  The cliffs of Elizabeth Island, in the Low
Archipelago, are eighty feet high, and appear, from Captain Beechey's
description, to consist of a homogeneous coral-rock.  From the isolated
position of this island, we may safely infer that it is an upraised atoll,
and therefore that it has been formed by masses of coral, grown together.
Savage Island seems, from the description of the younger Forster (Forster's
"Voyage round the World with Cook," volume ii., pages 163, 167.), to have a
similar structure, and its shores are about forty feet high: some of the
Cook Islands also appear (Williams's "Narrative of Missionary Enterprise,"
page 30.) to be similarly composed.  Captain Belcher, R.N., in a letter
which Captain Beaufort showed me at the admiralty, speaking of Bow atoll,
says, "I have succeeded in boring forty-five feet through coral-sand, when
the auger became jammed by the falling in of the surrounding CREAMY
matter."  On one of the Maldiva atolls, Captain Moresby bored to a depth of
twenty-six feet, when his auger also broke: he has had the kindness to
give me the matter brought up; it is perfectly white, and like finely
triturated coral-rock.

In my description of Keeling atoll, I have given some facts, which show
that the reef probably has grown outwards; and I have found, just within
the outer margin, the great mounds of Porites and of Millepora, with their
summits lately killed, and their sides subsequently thickened by the growth
of the coral: a layer, also, of Nullipora had already coated the dead
surface.  As the external slope of the reef is the same round the whole of
this atoll, and round many other atolls, the angle of inclination must
result from an adaption between the growing powers of the coral, and the
force of the breakers, and their action on the loose sediment.  The reef,
therefore, could not increase outwards, without a nearly equal addition to
every part of the slope, so that the original inclination might be
preserved, and this would require a large amount of sediment, all derived
from the wear of corals and shells, to be added to the lower part.
Moreover, at Keeling atoll, and probably in many other cases, the different
kinds of corals would have to encroach on each other; thus the Nulliporae
cannot increase outwards without encroaching on the Porites and Millepora
complanata, as is now taking place; nor these latter without encroaching on
the strongly branched Madreporet, the Millepora alcicornis, and some
Astraeas; nor these again without a foundation being formed for them within
the requisite depth, by the accumulation of sediment.  How slow, then, must
be the ordinary lateral or outward growth of such reefs.  But off Christmas
atoll, where the sea is much more shallow than is usual, we have good
reason to believe that, within a period not very remote, the reef has
increased considerably in width.  The land has the extraordinary breadth of
three miles; it consists of parallel ridges of shells and broken corals,
which furnish "an incontestable proof," as observed by Cook (Cook's "Third
Voyage," book III., chapter x.), "that the island has been produced by
accessions from the sea, and is in a state of increase."  The land is
fronted by a coral-reef, and from the manner in which islets are known to
be formed, we may feel confident that the reef was not three miles wide,
when the first, or most backward ridge, was thrown up; and, therefore, we
must conclude that the reef has grown outwards during the accumulation of
the successive ridges.  Here then, a wall of coral-rock of very
considerable breadth has been formed by the outward growth of the living
margin, within a period during which ridges of shells and corals, lying on
the bare surface, have not decayed.  There can be little doubt, from the
account given by Captain Beechey, that Matilda atoll, in the Low
Archipelago, has been converted in the space of thirty-four years, from
being, as described by the crew of a wrecked whaling vessel, a "reef of
rocks" into a lagoon-island, fourteen miles in length, with "one of its
sides covered nearly the whole way with high trees."  (Beechey's "Voyage to
the Pacific," chapter vii. and viii.)  The islets, also, on Keeling atoll,
it has been shown, have increased in length, and since the construction of
an old chart, several of them have become united into one long islet; but
in this case, and in that of Matilda atoll, we have no proof, and can only
infer as probable, that the reef, that is the foundation of the islets, has
increased as well as the islets themselves.

After these considerations, I attach little importance, as indicating the
ordinary and still less the possible rate of OUTWARD growth of coral-reefs,
to the fact that certain reefs in the Red Sea have not increased during a
long interval of time; or to other such cases, as that of Ouluthy atoll in
the Caroline group, where every islet, described a thousand years before by
Cantova was found in the same state by Lutke (F. Lutke's "Voyage autour du
Monde."  In the group Elato, however, it appears that what is now the islet
Falipi, is called in Cantova's Chart, the Banc de Falipi.  It is not stated
whether this has been caused by the growth of coral, or by the accumulation
of sand.),--without it could be shown that, in these cases, the conditions
were favourable to the vigorous and unopposed growth of the corals living
in the different zones of depth, and that a proper basis for the extent of
the reef was present.  The former conditions must depend on many
contingencies, and in the deep oceans where coral formations most abound, a
basis within the requisite depth can rarely be present.

Nor do I attach any importance to the fact of certain submerged reefs, as
those off Tahiti, or those within Diego Garcia not now being nearer the
surface than they were many years ago, as an indication of the rate under
favourable circumstances of the UPWARD growth of reefs; after it has been
shown, that all the reefs have grown to the surface in some of the Chagos
atolls, but that in neighbouring atolls which appear to be of equal
antiquity and to be exposed to the same external conditions, every reef
remains submerged; for we are almost driven to attribute this to a
difference, not in the rate of growth, but in the habits of the corals in
the two cases.

In an old-standing reef, the corals, which are so different in kind on
different parts of it, are probably all adapted to the stations they
occupy, and hold their places, like other organic beings, by a struggle one
with another, and with external nature; hence we may infer that their
growth would generally be slow, except under peculiarly favourable
circumstances.  Almost the only natural condition, allowing a quick upward
growth of the whole surface of a reef, would be a slow subsidence of the
area in which it stood; if, for instance, Keeling atoll were to subside two
or three feet, can we doubt that the projecting margin of live coral, about
half an inch in thickness, which surrounds the dead upper surfaces of the
mounds of Porites, would in this case form a concentric layer over them,
and the reef thus increase upwards, instead of, as at present, outwards?
The Nulliporae are now encroaching on the Porites and Millepora, but in
this case might we not confidently expect that the latter would, in their
turn, encroach on the Nulliporae?  After a subsidence of this kind, the sea
would gain on the islets, and the great fields of dead but upright corals
in the lagoon, would be covered by a sheet of clear water; and might we not
then expect that these reefs would rise to the surface, as they anciently
did when the lagoon was less confined by islets, and as they did within a
period of ten years in the schooner-channel, cut by the inhabitants?  In
one of the Maldiva atolls, a reef, which within a very few years existed as
an islet bearing cocoa-nut trees, was found by Lieutenant Prentice
"ENTIRELY COVERED WITH LIVE CORAL AND MADREPORE."  The natives believe that
the islet was washed away by a change in the currents, but if, instead of
this, it had quietly subsided, surely every part of the island which
offered a solid foundation, would in a like manner have become coated with
living coral.

Through steps such as these, any thickness of rock, composed of a singular
intermixture of various kinds of corals, shells, and calcareous sediment,
might be formed; but without subsidence, the thickness would necessarily be
determined by the depth at which the reef-building polypifers can exist.
If it be asked, at what rate in years I suppose a reef of coral favourably
circumstanced could grow up from a given depth; I should answer, that we
have no precise evidence on this point, and comparatively little concern
with it.  We see, in innumerable points over wide areas, that the rate has
been sufficient, either to bring up the reefs from various depths to the
surface, or, as is more probable, to keep them at the surface, during
progressive subsidences; and this is a much more important standard of
comparison than any cycle of years.

It may, however, be inferred from the following facts, that the rate in
years under favourable circumstances would be very far from slow.  Dr.
Allan, of Forres, has, in his MS. Thesis deposited in the library of the
Edinburgh University (extracts from which I owe to the kindness of Dr.
Malcolmson), the following account of some experiments, which he tried
during his travels in the years 1830 to 1832 on the east coast of
Madagascar.  "To ascertain the rise and progress of the coral-family, and
fix the number of species met with at Foul Point (latitude 17 deg 40')
twenty species of coral were taken off the reef and planted apart on a
sand-bank THREE FEET DEEP AT LOW WATER.  Each portion weighed ten pounds,
and was kept in its place by stakes.  Similar quantities were placed in a
clump and secured as the rest.  This was done in December 1830.  In July
following, each detached mass was nearly level with the sea at low water,
quite immovable, and several feet long, stretching as the parent reef, with
the coast current from north to south.  The masses accumulated in a clump
were found equally increased, but some of the species in such unequal
ratios, as to be growing over each other."  The loss of Dr. Allan's
magnificent collection by shipwreck, unfortunately prevents its being known
to what genera these corals belonged; but from the numbers experimented on,
it is certain that all the more conspicuous kinds must have been included.
Dr. Allan informs me, in a letter, that he believes it was a Madrepora,
which grew most vigorously.  One may be permitted to suspect that the level
of the sea might possibly have been somewhat different at the two stated
periods; nevertheless, it is quite evident that the growth of the ten-pound
masses, during the six or seven months, at the end of which they were found
immovably fixed (It is stated by De la Beche ("Geological Manual," page
143), on the authority of Mr. Lloyd, who surveyed the Isthmus of Panama,
that some specimens of Polypifers, placed by him in a sheltered pool of
water, were found in the course of a few days firmly fixed by the secretion
of a stony matter, to the bottom) and several feet in length, must have
been very great.  The fact of the different kinds of coral, when placed in
one clump, having increased in extremely unequal ratios, is very
interesting, as it shows the manner in which a reef, supporting many
species of coral, would probably be affected by a change in the external
conditions favouring one kind more than another.  The growth of the masses
of coral in N. and S. lines parallel to the prevailing currents, whether
due to the drifting of sediment or to the simple movement of the water, is,
also, a very interesting circumstance.

A fact, communicated to me by Lieutenant Wellstead, I.N., in some degree
corroborates the result of Dr. Allan's experiments: it is, that in the
Persian Gulf a ship had her copper bottom encrusted in the course of twenty
months with a layer of coral, TWO FEET in thickness, which it required
great force to remove, when the vessel was docked: it was not ascertained
to what order this coral belonged.  The case of the schooner-channel choked
up with coral in an interval of less than ten years, in the lagoon of
Keeling atoll, should be here borne in mind.  We may also infer, from the
trouble which the inhabitants of the Maldiva atolls take to root out, as
they express it, the coral-knolls from their harbours, that their growth
can hardly be very slow.  (Mr. Stutchbury ("West of England Journal", No.
I., page 50.) has described a specimen of Agaricia, "weighing 2 lbs. 9 oz.,
which surrounds a species of oyster, whose age could not be more than two
years, and yet is completely enveloped by this dense coral."  I presume
that the oyster was living when the specimen was procured; otherwise the
fact tells nothing.  Mr. Stutchbury also mentions an anchor, which had
become entirely encrusted with coral in fifty years; other cases, however,
are recorded of anchors which have long remained amidst coral-reefs without
having become coated.  The anchor of the "Beagle", in 1832, after having
been down exactly one month at Rio de Janeiro, was so thickly coated by two
species of Tubularia, that large spaces of the iron were entirely
concealed; the tufts of this horny zoophyte were between two and three
inches in length.  It has been attempted to compute, but I believe
erroneously, the rate of growth of a reef, from the fact mentioned by
Captain Beechey, of the Chama gigas being embedded in coral-rock.  But it
should be remembered, that some species of this genus invariably live, both
whilst young and old, in cavities, which the animal has the power of
enlarging with its growth.  I saw many of these shells thus embedded in the
outer "flat" of Keeling atoll, which is composed of dead rock; and
therefore the cavities in this case had no relation whatever with the
growth of coral.  M. Lesson, also, speaking of this shell (Partie Zoolog.
"Voyage de la 'Coquille'"), has remarked, "que constamment ses valves
etaient engages completement dans la masse des Madrepores.")

From the facts given in this section, it may be concluded, first, that
considerable thicknesses of rock have certainly been formed within the
present geological area by the growth of coral and the accumulation of its
detritus; and, secondly, that the increase of individual corals and of
reefs, both outwards or horizontally and upwards or vertically, under the
peculiar conditions favourable to such increase, is not slow, when referred
either to the standard of the average oscillations of level in the earth's
crust, or to the more precise but less important one of a cycle of years.


SECTION 4.III.--ON THE DEPTHS AT WHICH REEF-BUILDING POLYPIFERS CAN LIVE.

I have already described in detail, which might have appeared trivial, the
nature of the bottom of the sea immediately surrounding Keeling atoll; and
I will now describe with almost equal care the soundings off the
fringing-reefs of Mauritius.  I have preferred this arrangement, for the sake
of grouping together facts of a similar nature.  I sounded with the wide
bell-shaped lead which Captain Fitzroy used at Keeling Island, but my
examination of the bottom was confined to a few miles of coast (between
Port Louis and Tomb Bay) on the leeward side of the island.  The edge of
the reef is formed of great shapeless masses of branching Madrepores, which
chiefly consist of two species,--apparently M. corymbosa and pocillifera,--
mingled with a few other kinds of coral.  These masses are separated from
each other by the most irregular gullies and cavities, into which the lead
sinks many feet.  Outside this irregular border of Madrepores, the water
deepens gradually to twenty fathoms, which depth generally is found at the
distance of from half to three-quarters of a mile from the reef.  A little
further out the depth is thirty fathoms, and thence the bank slopes rapidly
into the depths of the ocean.  This inclination is very gentle compared
with that outside Keeling and other atolls, but compared with most coasts
it is steep.  The water was so clear outside the reef, that I could
distinguish every object forming the rugged bottom.  In this part, and to a
depth of eight fathoms, I sounded repeatedly, and at each cast pounded the
bottom with the broad lead, nevertheless the arming invariably came up
perfectly clean, but deeply indented.  From eight to fifteen fathoms a
little calcareous sand was occasionally brought up, but more frequently the
arming was simply indented.  In all this space the two Madrepores above
mentioned, and two species of Astraea, with rather large stars, seemed the
commonest kinds (Since the preceding pages were printed off, I have
received from Mr. Lyell a very interesting pamphlet, entitled "Remarks upon
Coral Formations," etc., by J. Couthouy, Boston, United States, 1842.
There is a statement (page 6), on the authority of the Rev. J. Williams,
corroborating the remarks made by Ehrenberg and Lyell (page 71 of this
volume), on the antiquity of certain individual corals in the Red Sea and
at Bermuda; namely, that at Upolu, one of the Navigator Islands,
"particular clumps of coral are known to the fishermen by name, derived
from either some particular configuration or tradition attached to them,
and handed down from time immemorial."  With respect to the thickness of
masses of coral-rock, it clearly appears, from the descriptions given by
Mr. Couthouy (pages 34, 58) that Mangaia and Aurora Islands are upraised
atolls, composed of coral rock: the level summit of the former is about
three hundred feet, and that of Aurora Island is two hundred feet above the
sea-level.); and it must be noticed that twice at the depth of fifteen
fathoms, the arming was marked with a clean impression of an Astraea.
Besides these lithophytes, some fragments of the Millepora alcicornis,
which occurs in the same relative position at Keeling Island, were brought
up; and in the deeper parts there were large beds of a Seriatopora,
different from S. subulata, but closely allied to it.  On the beach within
the reef, the rolled fragments consisted chiefly of the corals just
mentioned, and of a massive Porites, like that at Keeling atoll, of a
Meandrina, Pocillopora verrucosa, and of numerous fragments of Nullipora.
From fifteen to twenty fathoms the bottom was, with few exceptions, either
formed of sand, or thickly covered with Seriatopora: this delicate coral
seems to form at these depths extensive beds unmingled with any other kind.
At twenty fathoms, one sounding brought up a fragment of Madrepora
apparently M. pocillifera, and I believe it is the same species (for I
neglected to bring specimens from both stations) which mainly forms the
upper margin of the reef; if so, it grows in depths varying from 0 to 20
fathoms.  Between 20 and 23 fathoms I obtained several soundings, and they
all showed a sandy bottom, with one exception at 30 fathoms, when the
arming came up scooped out, as if by the margin of a large Caryophyllia.
Beyond 33 fathoms I sounded only once; and from 86 fathoms, at the distance
of one mile and a third from the edge of the reef, the arming brought up
calcareous sand with a pebble of volcanic rock.  The circumstance of the
arming having invariably come up quite clean, when sounding within a
certain number of fathoms off the reefs of Mauritius and Keeling atoll
(eight fathoms in the former case, and twelve in the latter) and of its
having always come up (with one exception) smoothed and covered with sand,
when the depth exceeded twenty fathoms, probably indicates a criterion, by
which the limits of the vigorous growth of coral might in all cases be
readily ascertained.  I do not, however, suppose that if a vast number of
soundings were obtained round these islands, the limit above assigned would
be found never to vary, but I conceive the facts are sufficient to show,
that the exceptions would be few.  The circumstance of a GRADUAL change, in
the two cases, from a field of clean coral to a smooth sandy bottom, is far
more important in indicating the depth at which the larger kinds of coral
flourish than almost any number of separate observations on the depth, at
which certain species have been dredged up.  For we can understand the
gradation, only as a prolonged struggle against unfavourable conditions.
If a person were to find the soil clothed with turf on the banks of a
stream of water, but on going to some distance on one side of it, he
observed the blades of grass growing thinner and thinner, with intervening
patches of sand, until he entered a desert of sand, he would safely
conclude, especially if changes of the same kind were noticed in other
places, that the presence of the water was absolutely necessary to the
formation of a thick bed of turf: so may we conclude, with the same
feeling of certainty, that thick beds of coral are formed only at small
depths beneath the surface of the sea.

I have endeavoured to collect every fact, which might either invalidate or
corroborate this conclusion.  Captain Moresby, whose opportunities for
observation during his survey of the Maldiva and Chagos Archipelagoes have
been unrivalled, informs me, that the upper part or zone of the steep-sided
reefs, on the inner and outer coasts of the atolls in both groups,
invariably consists of coral, and the lower parts of sand.  At seven or
eight fathoms depth, the bottom is formed, as could be seen through the
clear water, of great living masses of coral, which at about ten fathoms
generally stand some way apart from each other, with patches of white sand
between them, and at a little greater depth these patches become united
into a smooth steep slope, without any coral.  Captain Moresby, also,
informs me in support of his statement, that he found only decayed coral on
the Padua Bank (northern part of the Laccadive group) which has an average
depth between twenty-five and thirty-five fathoms, but that on some other
banks in the same group with only ten or twelve fathoms water on them (for
instance, the Tillacapeni bank), the coral was living.

With regard to the coral-reefs in the Red Sea, Ehrenberg has the following
passage:--"The living corals do not descend there into great depths.  On
the edges of islets and near reefs, where the depth was small, very many
lived; but we found no more even at six fathoms.  The pearl-fishers at
Yemen and Massaua asserted that there was no coral near the pearl-banks at
nine fathoms depth, but only sand.  We were not able to institute any more
special researches."  (Ehrenberg, "Uber die Natur," etc., page 50.)  I am,
however, assured both by Captain Moresby and Lieutenant Wellstead, that in
the more northern parts of the Red Sea, there are extensive beds of living
coral at a depth of twenty-five fathoms, in which the anchors of their
vessels were frequently entangled.  Captain Moresby attributes the less
depth, at which the corals are able to live in the places mentioned by
Ehrenberg, to the greater quantity of sediment there; and the situations,
where they were flourishing at the depth of twenty-five fathoms, were
protected, and the water was extraordinarily limpid.  On the leeward side
of Mauritius where I found the coral growing at a somewhat greater depth
than at Keeling atoll, the sea, owing apparently to its tranquil state, was
likewise very clear.  Within the lagoons of some of the Marshall atolls,
where the water can be but little agitated, there are, according to
Kotzebue, living beds of coral in twenty-five fathoms.  From these facts,
and considering the manner in which the beds of clean coral off Mauritius,
Keeling Island, the Maldiva and Chagos atolls, graduated into a sandy
slope, it appears very probable that the depth, at which reef-building
polypifers can exist, is partly determined by the extent of inclined
surface, which the currents of the sea and the recoiling waves have the
power to keep free from sediment.

MM. Quoy and Gaimard ("Annales des Sci. Nat." tom. vi.) believe that the
growth of coral is confined within very limited depths; and they state that
they never found any fragment of an Astraea (the genus they consider most
efficient in forming reefs) at a depth above twenty-five or thirty feet.
But we have seen that in several places the bottom of the sea is paved with
massive corals at more than twice this depth; and at fifteen fathoms (or
twice this depth) off the reefs of Mauritius, the arming was marked with
the distinct impression of a living Astraea.  Millepora alcicornis lives in
from 0 to 12 fathoms, and the genera Madrepora and Seriatopora from 0 to 20
fathoms.  Captain Moresby has given me a specimen of Sideropora scabra
(Porites of Lamarck) brought up alive from 17 fathoms.  Mr. Couthouy
("Remarks on Coral Formations," page 12.) states that he has dredged up on
the Bahama banks considerable masses of Meandrina from 16 fathoms, and he
has seen this coral growing in 20 fathoms.  A Caryophyllia, half an inch in
diameter, was dredged up alive from 80 fathoms off Juan Fernandez (latitude
33 deg S.) by Captain P.P. King (I am indebted to Mr. Stokes for having
kindly communicated this fact to me, together with much other valuable
information.): this is the most remarkable fact with which I am
acquainted, showing the depth at which a genus of corals often found on
reefs, can exist.

We ought, however, to feel less surprise at this fact, as Caryophyllia
alone of the lamelliform genera, ranges far beyond the tropics; it is found
in Zetland (Fleming's "British Animals," genus Caryophyllia.) in Latitude
60 deg N. in deep water, and I procured a small species from Tierra del
Fuego in Latitude 53 deg S.  Captain Beechey informs me, that branches of
pink and yellow coral were frequently brought up from between twenty and
twenty-five fathoms off the Low atolls; and Lieutenant Stokes, writing to
me from the N.W. coast of Australia, says that a strongly branched coral
was procured there from thirty fathoms; unfortunately it is not known to
what genera these corals belong.

(I will record in the form of a note all the facts that I have been able to
collect on the depths, both within and without the tropics, at which those
corals and corallines can live, which there is no reason to suppose ever
materially aid in the construction of a reef.

(In the following list the name of the Zoophyte is followed by the depth in
fathoms, the country and degrees S. latitude, and the authority.  Where no
authority is given, the observation is Darwin's own.)

SERTULARIA, 40, Cape Horn 66.

CELLARIA, 40, Cape Horn 66.

CELLARIA, A minute scarlet encrusting species, found living, 190, Keeling
Atoll, 12.

CELLARIA, An allied, small stony sub-generic form, 48, St Cruz Riv. 50.

A coral allied to VINCULARIA, with eight rows of cells, 40, Cape Horn.

TUBULIPORA, near to T. patima, 40, Cape Horn.

TUBULIPORA, near to T. patima, 94, East Chiloe 43.

CELLEPORA, several species, and allied sub-generic forms, 40, Cape Horn.

CELLEPORA, several species, and allied sub-generic forms, 40 and 57, Chonos
Archipelago 45.

CELLEPORA, several species, and allied sub-generic forms, 48, St Cruz 50.

ESCHARA, 30, Tierra del Fuego 53.

ESCHARA, 48, St Cruz R. 50.

RETEPORA, 40, Cape Horn.

RETEPORA, 100, Cape of Good Hope 34, Quoy and Gaimard, "Ann. Scien. Nat."
tome vi., page 284.

MILLEPORA, a strong coral with cylindrical branches, of a pink colour,
about two inches high, resembling in the form of its orifices M. aspera of
Lamarck, 94 and 30, E. Chiloe 43, Tierra del Fuego 53.

CORALIUM, 120, Barbary 33 N., Peyssonel in paper read to Royal Society May
1752.

ANTIPATHES, 16, Chonos 45.

GORGONIA (or an allied form), 160, Abrolhos on the coast of Brazil 18,
Captain Beechey informed me of this fact in a letter.

Ellis ("Nat. Hist. of Coralline," page 96) states that Ombellularia was
procured in latitude 79 deg N. STICKING to a LINE from the depth of 236
fathoms; hence this coral either must have been floating loose, or was
entangled in stray line at the bottom.  Off Keeling atoll a compound
Ascidia (Sigillina) was brought up from 39 fathoms, and a piece of sponge,
apparently living, from 70, and a fragment of Nullipora also apparently
living from 92 fathoms.  At a greater depth than 90 fathoms off this coral
island, the bottom was thickly strewed with joints of Halimeda and small
fragments of other Nulliporae, but all dead.  Captain B. Allen, R.N.,
informs me that in the survey of the West Indies it was noticed that
between the depth of 10 and 200 fathoms, the sounding lead very generally
came up coated with the dead joints of a Halimeda, of which he showed me
specimens.  Off Pernambuco, in Brazil, in about twelve fathoms, the bottom
was covered with fragments dead and alive of a dull red Nullipora, and I
infer from Roussin's chart, that a bottom of this kind extends over a wide
area.  On the beach, within the coral-reefs of Mauritius, vast quantities
of fragments of Nulliporae were piled up.  From these facts it appears,
that these simply organized bodies are amongst the most abundant
productions of the sea.)

Although the limit of depth, at which each particular kind of coral ceases
to exist, is far from being accurately known; yet when we bear in mind the
manner in which the clumps of coral gradually became infrequent at about
the same depth, and wholly disappeared at a greater depth than twenty
fathoms, on the slope round Keeling atoll, on the leeward side of the
Mauritius, and at rather less depth, both without and within the atolls of
the Maldiva and Chagos Archipelagoes; and when we know that the reefs round
these islands do not differ from other coral formations in their form and
structure, we may, I think, conclude that in ordinary cases, reef-building
polypifers do not flourish at greater depths than between twenty and thirty
fathoms.

It has been argued ("Journal of the Royal Geographical Society," 1831, page
218.) that reefs may possibly rise from very great depths through the means
of small corals, first making a platform for the growth of the stronger
kinds.  This, however, is an arbitrary supposition: it is not always
remembered, that in such cases there is an antagonist power in action,
namely, the decay of organic bodies, when not protected by a covering of
sediment, or by their own rapid growth.  We have, moreover, no right to
calculate on unlimited time for the accumulation of small organic bodies
into great masses.  Every fact in geology proclaims that neither the land,
nor the bed of the sea retain for indefinite periods the same level.  As
well might it be imagined that the British Seas would in time become choked
up with beds of oysters, or that the numerous small corallines off the
inhospitable shores of Tierra del Fuego would in time form a solid and
extensive coral-reef.


CHAPTER V.--THEORY OF THE FORMATION OF THE DIFFERENT CLASSES OF
CORAL-REEFS.

The atolls of the larger archipelagoes are not formed on submerged craters,
or on banks of sediment.--Immense areas interspersed with atolls.--Their
subsidence.--The effects of storms and earthquakes on atolls.--Recent
changes in their state.--The origin of barrier-reefs and of atolls.--Their
relative forms.--The step-formed ledges and walls round the shores of some
lagoons.--The ring-formed reefs of the Maldiva atolls.--The submerged
condition of parts or of the whole of some annular reefs.--The disseverment
of large atolls.--The union of atolls by linear reefs.--The Great Chagos
Bank.--Objections from the area and amount of subsidence required by the
theory, considered.--The probable composition of the lower parts of atolls.

The naturalists who have visited the Pacific, seem to have had their
attention riveted by the lagoon-islands, or atolls,--those singular rings
of coral-land which rise abruptly out of the unfathomable ocean--and have
passed over, almost unnoticed, the scarcely less wonderful encircling
barrier-reefs.  The theory most generally received on the formation of
atolls, is that they are based on submarine craters; but where can we find
a crater of the shape of Bow atoll, which is five times as long as it is
broad (Plate I., Figure 4); or like that of Menchikoff Island (Plate II.,
Figure 3.), with its three loops, together sixty miles in length; or like
Rimsky Korsacoff, narrow, crooked, and fifty-four miles long; or like the
northern Maldiva atolls, made up of numerous ring-formed reefs, placed on
the margin of a disc,--one of which discs is eighty-eight miles in length,
and only from ten to twenty in breadth?  It is, also, not a little
improbable, that there should have existed as many craters of immense size
crowded together beneath the sea, as there are now in some parts atolls.
But this theory lies under a greater difficulty, as will be evident, when
we consider on what foundations the atolls of the larger archipelagoes
rest: nevertheless, if the rim of a crater afforded a basis at the proper
depth, I am far from denying that a reef like a perfectly characterised
atoll might not be formed; some such, perhaps, now exist; but I cannot
believe in the possibility of the greater number having thus originated.

An earlier and better theory was proposed by Chamisso (Kotzebue's "First
Voyage," volume iii., page 331.); he supposes that as the more massive
kinds of corals prefer the surf, the outer portions, in a reef rising from
a submarine basis, would first reach the surface and consequently form a
ring.  But on this view it must be assumed, that in every case the basis
consists of a flat bank; for if it were conically formed, like a
mountainous mass, we can see no reason why the coral should spring up from
the flanks, instead of from the central and highest parts: considering the
number of the atolls in the Pacific and Indian Oceans, this assumption is
very improbable.  As the lagoons of atolls are sometimes even more than
forty fathoms deep, it must, also, be assumed on this view, that at a depth
at which the waves do not break, the coral grows more vigorously on the
edges of a bank than on its central part; and this is an assumption without
any evidence in support of it.  I remarked, in the third chapter, that a
reef, growing on a detached bank, would tend to assume an atoll-like
structure; if, therefore, corals were to grow up from a bank, with a level
surface some fathoms submerged, having steep sides and being situated in a
deep sea, a reef not to be distinguished from an atoll, might be formed: I
believe some such exist in the West Indies.  But a difficulty of the same
kind with that affecting the crater theory, runners, as we shall presently
see, this view inapplicable to the greater number of atolls.

No theory worthy of notice has been advanced to account for those
barrier-reefs, which encircle islands of moderate dimensions.  The great
reef which fronts the coast of Australia has been supposed, but without any
special facts, to rest on the edge of a submarine precipice, extending
parallel to the shore.  The origin of the third class or of fringing-reefs
presents, I believe, scarcely any difficulty, and is simply consequent on
the polypifers not growing up from great depths, and their not flourishing
close to gently shelving beaches where the water is often turbid.

What cause, then, has given to atolls and barrier-reefs their
characteristic forms?  Let us see whether an important deduction will not
follow from the consideration of these two circumstances, first, the
reef-building corals flourishing only at limited depths; and secondly, the
vastness of the areas interspersed with coral-reefs and coral-islets, none
of which rise to a greater height above the level of the sea, than that
attained by matter thrown up by the waves and winds.  I do not make this
latter statement vaguely; I have carefully sought for descriptions of every
island in the intertropical seas; and my task has been in some degree
abridged by a map of the Pacific, corrected in 1834 by MM. D'Urville and
Lottin, in which the low islands are distinguished from the high ones (even
from those much less than a hundred feet in height) by being written
without a capital letter; I have detected a few errors in this map,
respecting the height of some of the islands, which will be noticed in the
Appendix, where I treat of coral formations in geographical order.  To the
Appendix, also, I must refer for a more particular account of the data on
which the statements on the next page are grounded.  I have ascertained,
and chiefly from the writings of Cook, Kotzebue, Bellinghausen, Duperrey,
Beechey, and Lutke, regarding the Pacific; and from Moresby (See also
Captain Owen's and Lieutenant Wood's papers in the "Geographical Journal",
on the Maldiva and Laccadive Archipelagoes.  These officers particularly
refer to the lowness of the islets; but I chiefly ground my assertion
respecting these two groups, and the Chagos group, from information
communicated to me by Captain Moresby.) with respect to the Indian Ocean,
that in the following cases the term "low island" strictly means land of
the height commonly attained by matter thrown up by the winds and the waves
of an open sea.  If we draw a line (the plan I have always adopted) joining
the external atolls of that part of the Low Archipelago in which the
islands are numerous, the figure will be a pointed ellipse (reaching from
Hood to Lazaref Island), of which the longer axis is 840 geographical
miles, and the shorter 420 miles; in this space (I find from Mr. Couthouy's
pamphlet (page 58) that Aurora Island is about two hundred feet in height;
it consists of coral-rock, and seems to have been formed by the elevation
of an atoll.  It lies north-east of Tahiti, close without the line bounding
the space coloured dark blue in the map appended to this volume.  Honden
Island, which is situated in the extreme north-west part of the Low
Archipelago, according to measurements made on board the "Beagle", whilst
sailing by, is 114 feet from the SUMMIT OF THE TREES to the water's edge.
This island appeared to resemble the other atolls of the group.) none of
the innumerable islets united into great rings rise above the stated level.
The Gilbert group is very narrow, and 300 miles in length.  In a prolonged
line from this group, at the distance of 240 miles, is the Marshall
Archipelago, the figure of which is an irregular square, one end being
broader than the other; its length is 520 miles, with an average width of
240; these two groups together are 1,040 miles in length, and all their
islets are low.  Between the southern end of the Gilbert and the northern
end of Low Archipelago, the ocean is thinly strewed with islands, all of
which, as far as I have been able to ascertain, are low; so that from
nearly the southern end of the Low Archipelago, to the northern end of the
Marshall Archipelago, there is a narrow band of ocean, more than 4,000
miles in length, containing a great number of islands, all of which are
low.  In the western part of the Caroline Archipelago, there is a space of
480 miles in length, and about 100 broad, thinly interspersed with low
islands.  Lastly, in the Indian Ocean, the archipelago of the Maldivas is
470 miles in length, and 60 in breadth; that of the Laccadives is 150 by
100 miles; as there is a low island between these two groups, they may be
considered as one group of 1,000 miles in length.  To this may be added the
Chagos group of low islands, situated 280 miles distant, in a line
prolonged from the southern extremity of the Maldivas.  This group,
including the submerged banks, is 170 miles in length and 80 in breadth.
So striking is the uniformity in direction of these three archipelagoes,
all the islands of which are low, that Captain Moresby, in one of his
papers, speaks of them as parts of one great chain, nearly 1,500 miles
long.  I am, then, fully justified in repeating, that enormous spaces, both
in the Pacific and Indian Oceans, are interspersed with islands, of which
not one rises above that height, to which the waves and winds in an open
sea can heap up matter.

On what foundations, then, have these reefs and islets of coral been
constructed?  A foundation must originally have been present beneath each
atoll at that limited depth, which is indispensable for the first growth of
the reef-building polypifers.  A conjecture will perhaps be hazarded, that
the requisite bases might have been afforded by the accumulation of great
banks of sediment, which owing to the action of superficial currents (aided
possibly by the undulatory movement of the sea) did not quite reach the
surface,--as actually appears to have been the case in some parts of the
West Indian Sea.  But in the form and disposition of the groups of atolls,
there is nothing to countenance this notion; and the assumption without any
proof, that a number of immense piles of sediment have been heaped on the
floor of the great Pacific and Indian Oceans, in their central parts far
remote from land, and where the dark blue colour of the limpid water
bespeaks its purity, cannot for one moment be admitted.

The many widely-scattered atolls must, therefore, rest on rocky bases.  But
we cannot believe that the broad summit of a mountain lies buried at the
depth of a few fathoms beneath every atoll, and nevertheless throughout the
immense areas above-named, with not one point of rock projecting above the
level of the sea; for we may judge with some accuracy of mountains beneath
the sea, by those on the land; and where can we find a single chain several
hundred miles in length and of considerable breadth, much less several such
chains, with their many broad summits attaining the same height, within
from 120 to 180 feet?  If the data be thought insufficient, on which I have
grounded my belief, respecting the depth at which the reef-building
polypifers can exist, and it be assumed that they can flourish at a depth
of even one hundred fathoms, yet the weight of the above argument is but
little diminished, for it is almost equally improbable, that as many
submarine mountains, as there are low islands in the several great and
widely separated areas above specified, should all rise within six hundred
feet of the surface of the sea and not one above it, as that they should be
of the same height within the smaller limit of one or two hundred feet.  So
highly improbable is this supposition, that we are compelled to believe,
that the bases of the many atolls did never at any one period all lie
submerged within the depth of a few fathoms beneath the surface, but that
they were brought into the requisite position or level, some at one period
and some at another, through movements in the earth's crust.  But this
could not have been effected by elevation, for the belief that points so
numerous and so widely separated were successively uplifted to a certain
level, but that not one point was raised above that level, is quite as
improbable as the former supposition, and indeed differs little from it.
It will probably occur to those who have read Ehrenberg's account of the
Reefs of the Red Sea, that many points in these great areas may have been
elevated, but that as soon as raised, the protuberant parts were cut off by
the destroying action of the waves: a moment's reflection, however, on the
basin-like form of the atolls, will show that this is impossible; for the
upheaval and subsequent abrasion of an island would leave a flat disc,
which might become coated with coral, but not a deeply concave surface;
moreover, we should expect to see, in some parts at least, the rock of the
foundation brought to the surface.  If, then, the foundations of the many
atolls were not uplifted into the requisite position, they must of
necessity have subsided into it; and this at once solves every difficulty
(The additional difficulty on the crater hypothesis before alluded to, will
now be evident; for on this view the volcanic action must be supposed to
have formed within the areas specified a vast number of craters, all rising
within a few fathoms of the surface, and not one above it.  The supposition
that the craters were at different times upraised above the surface, and
were there abraded by the surf and subsequently coated by corals, is
subject to nearly the same objections with those given above in this
paragraph; but I consider it superfluous to detail all the arguments
opposed to such a notion.  Chamisso's theory, from assuming the existence
of so many banks, all lying at the proper depth beneath the water, is also
vitally defective.  The same observation applies to an hypothesis of
Lieutenant Nelson's ("Geolog. Trans." volume v., page 122), who supposes
that the ring-formed structure is caused by a greater number of germs of
corals becoming attached to the declivity, than to the central plateau of a
submarine bank: it likewise applies to the notion formerly entertained
(Forster's "Observ." page 151), that lagoon-islands owe their peculiar form
to the instinctive tendencies of the polypifers.  According to this latter
view, the corals on the outer margin of the reef instinctively expose
themselves to the surf in order to afford protection to corals living in
the lagoon, which belong to other genera, and to other families!), for we
may safely infer, from the facts given in the last chapter, that during a
gradual subsidence the corals would be favourably circumstanced for
building up their solid frame works and reaching the surface, as island
after island slowly disappeared.  Thus areas of immense extent in the
central and most profound parts of the great oceans, might become
interspersed with coral-islets, none of which would rise to a greater
height than that attained by detritus heaped up by the sea, and
nevertheless they might all have been formed by corals, which absolutely
required for their growth a solid foundation within a few fathoms of the
surface.

It would be out of place here to do more than allude to the many facts,
showing that the supposition of a gradual subsidence over large areas is by
no means improbable.  We have the clearest proof that a movement of this
kind is possible, in the upright trees buried under the strata many
thousand feet in thickness; we have also every reason for believing that
there are now large areas gradually sinking, in the same manner as others
are rising.  And when we consider how many parts of the surface of the
globe have been elevated within recent geological periods, we must admit
that there have been subsidences on a corresponding scale, for otherwise
the whole globe would have swollen.  It is very remarkable that Mr. Lyell
("Principles of Geology," sixth edition, volume iii., page 386.), even in
the first edition of his "Principles of Geology," inferred that the amount
of subsidence in the Pacific must have exceeded that of elevation, from the
area of land being very small relatively to the agents there tending to
form it, namely, the growth of coral and volcanic action.  But it will be
asked, are there any direct proofs of a subsiding movement in those areas,
in which subsidence will explain a phenomenon otherwise inexplicable?
This, however, can hardly be expected, for it must ever be most difficult,
excepting in countries long civilised, to detect a movement, the tendency
of which is to conceal the part affected.  In barbarous and semi-civilised
nations how long might not a slow movement, even of elevation such as that
now affecting Scandinavia, have escaped attention!

Mr. Williams (Williams's "Narrative of Missionary Enterprise," page 31.)
insists strongly that the traditions of the natives, which he has taken
much pains in collecting, do not indicate the appearance of any new
islands: but on the theory of a gradual subsidence, all that would be
apparent would be, the water sometimes encroaching slowly on the land, and
the land again recovering by the accumulation of detritus its former
extent, and perhaps sometimes the conversion of an atoll with coral islets
on it, into a bare or into a sunken annular reef.  Such changes would
naturally take place at the periods when the sea rose above its usual
limits, during a gale of more than ordinary strength; and the effects of
the two causes would be hardly distinguishable.  In Kotzebue's "Voyage"
there are accounts of islands, both in the Caroline and Marshall
Archipelagoes, which have been partly washed away during hurricanes; and
Kadu, the native who was on board one of the Russian vessels, said "he saw
the sea at Radack rise to the feet of the cocoa-nut trees; but it was
conjured in time."  (Kotzebue's "First Voyage," volume iii., page 168.)  A
storm lately entirely swept away two of the Caroline islands, and converted
them into shoals; it partly, also, destroyed two other islands.  (M.
Desmoulins in "Comptes Rendus," 1840, page 837.)  According to a tradition
which was communicated to Captain Fitzroy, it is believed in the Low
Archipelago, that the arrival of the first ship caused a great inundation,
which destroyed many lives.  Mr. Stutchbury relates, that in 1825, the
western side of Chain Atoll, in the same group, was completely devastated
by a hurricane, and not less than 300 lives lost: "in this instance it was
evident, even to the natives, that the hurricane alone was not sufficient
to account for the violent agitation of the ocean."  ("West of England
Journal", No. I., page 35.)  That considerable changes have taken place
recently in some of the atolls in the Low Archipelago, appears certain from
the case already given of Matilda Island: with respect to Whitsunday and
Gloucester Islands in this same group, we must either attribute great
inaccuracy to their discoverer, the famous circumnavigator Wallis, or
believe that they have undergone a considerable change in the period of
fifty-nine years, between his voyage and that of Captain Beechey's.
Whitsunday Island is described by Wallis as "about four miles long, and
three wide," now it is only one mile and a half long.  The appearance of
Gloucester Island, in Captain Beechey's words (Beechey's "Voyage to the
Pacific," chapter vii., and Wallis's "Voyage in the 'Dolphin'," chapter
iv.), has been accurately described by its discoverer, but its present form
and extent differ materially."  Blenheim reef, in the Chagos group,
consists of a water-washed annular reef, thirteen miles in circumference,
surrounding a lagoon ten fathoms deep: on its surface there were a few
worn patches of conglomerate coral-rock, of about the size of hovels; and
these Captain Moresby considered as being, without doubt, the last remnants
of islets; so that here an atoll has been converted into an atoll-formed
reef.  The inhabitants of the Maldiva Archipelago, as long ago as 1605,
declared, "that the high tides and violent currents were diminishing the
number of the islands"  (See an extract from Pyrard's Voyage in Captain
Owen's paper on the Maldiva Archipelago, in the "Geographical Journal",
volume ii., page 84.): and I have already shown, on the authority of
Captain Moresby, that the work of destruction is still in progress; but
that on the other hand the first formation of some islets is known to the
present inhabitants.  In such cases, it would be exceedingly difficult to
detect a gradual subsidence of the foundation, on which these mutable
structures rest.

Some of the archipelagoes of low coral-islands are subject to earthquakes:
Captain Moresby informs me that they are frequent, though not very strong,
in the Chagos group, which occupies a very central position in the Indian
Ocean, and is far from any land not of coral formation.  One of the islands
in this group was formerly covered by a bed of mould, which, after an
earthquake, disappeared, and was believed by the residents to have been
washed by the rain through the broken masses of underlying rock; the island
was thus rendered unproductive.  Chamisso (See Chamisso, in Kotzebue's
"First Voyage," volume iii., pages 182 and 136.) states, that earthquakes
are felt in the Marshall atolls, which are far from any high land, and
likewise in the islands of the Caroline Archipelago.  On one of the latter,
namely Oulleay atoll, Admiral Lutke, as he had the kindness to inform me,
observed several straight fissures about a foot in width, running for some
hundred yards obliquely across the whole width of the reef.  Fissures
indicate a stretching of the earth's crust, and, therefore, probably
changes in its level; but these coral-islands, which have been shaken and
fissured, certainly have not been elevated, and, therefore, probably they
have subsided.  In the chapter on Keeling atoll, I attempted to show by
direct evidence, that the island underwent a movement of subsidence, during
the earthquakes lately felt there.

The facts stand thus;--there are many large tracts of ocean, without any
high land, interspersed with reefs and islets, formed by the growth of
those kinds of corals, which cannot live at great depths; and the existence
of these reefs and low islets, in such numbers and at such distant points,
is quite inexplicable, excepting on the theory, that the bases on which the
reefs first became attached, slowly and successively sank beneath the level
of the sea, whilst the corals continued to grow upwards.  No positive facts
are opposed to this view, and some general considerations render it
probable.  There is evidence of change in form, whether or not from
subsidence, on some of these coral-islands; and there is evidence of
subterranean disturbances beneath them.  Will then the theory, to which we
have thus been led, solve the curious problem,--what has given to each
class of reef its peculiar form?

(PLATE: WOODCUT NO. 4.

AA--Outer edge of the reef at the level of the sea.

BB--Shores of the island.

A'A'--Outer edge of the reef, after its upward growth during a period of
subsidence.

CC--The lagoon-channel between the reef and the shores of the now encircled
land.

B'B'--The shores of the encircled island.

N.B.--In this, and the following woodcut, the subsidence of the land could
only be represented by an apparent rise in the level of the sea.

PLATE: WOODCUT NO. 5.

A'A'--Outer edges of the barrier-reef at the level of the sea.  The
cocoa-nut trees represent coral-islets formed on the reef.

CC--The lagoon-channel.

B'B'--The shores of the island, generally formed of low alluvial land and
of coral detritus from the lagoon-channel.

A"A"--The outer edges of the reef now forming an atoll.

C'--The lagoon of the newly formed atoll.  According to the scale, the
depth of the lagoon and of the lagoon-channel is exaggerated.)

Let us in imagination place within one of the subsiding areas, an island
surrounded by a "fringing-reef,"--that kind, which alone offers no
difficulty in the explanation of its origin.  Let the unbroken lines and
the oblique shading in the woodcut (No. 4) represent a vertical section
through such an island; and the horizontal shading will represent the
section of the reef.  Now, as the island sinks down, either a few feet at a
time or quite insensibly, we may safely infer from what we know of the
conditions favourable to the growth of coral, that the living masses bathed
by the surf on the margin of the reef, will soon regain the surface.  The
water, however, will encroach, little by little, on the shore, the island
becoming lower and smaller, and the space between the edge of the reef and
the beach proportionately broader.  A section of the reef and island in
this state, after a subsidence of several hundred feet, is given by the
dotted lines: coral-islets are supposed to have been formed on the new
reef, and a ship is anchored in the lagoon-channel.  This section is in
every respect that of an encircling barrier-reef; it is, in fact, a section
taken (The section has been made from the chart given in the "Atlas of the
Voyage of the 'Coquille'."  The scale is .57 of an inch to a mile.  The
height of the island, according to M. Lesson, is 4,026 feet.  The deepest
part of the lagoon-channel is 162 feet; its depth is exaggerated in the
woodcut for the sake of clearness.) east and west through the highest point
of the encircled island of Bolabola; of which a plan is given in Plate I.,
Figure 5.  The same section is more clearly shown in the following woodcut
(No. 5) by the unbroken lines.  The width of the reef, and its slope, both
on the outer and inner side, will have been determined by the growing
powers of the coral, under the conditions (for instance the force of the
breakers and of the currents) to which it has been exposed; and the
lagoon-channel will be deeper or shallower, in proportion to the growth of
the delicately branched corals within the reef, and to the accumulation of
sediment, relatively, also, to the rate of subsidence and the length of the
intervening stationary periods.

It is evident in this section, that a line drawn perpendicularly down from
the outer edge of the new reef to the foundation of solid rock, exceeds by
as many feet as there have been feet of subsidence, that small limit of
depth at which the effective polypifers can live--the corals having grown
up, as the whole sank down, from a basis formed of other corals and their
consolidated fragments.  Thus the difficulty on this head, which before
seemed so great, disappears.

As the space between the reef and the subsiding shore continued to increase
in breadth and depth, and as the injurious effects of the sediment and
fresh water borne down from the land were consequently lessened, the
greater number of the channels, with which the reef in its fringing state
must have been breached, especially those which fronted the smaller
streams, will have become choked up with the growth of coral: on the
windward side of the reef, where the coral grows most vigorously, the
breaches will probably have first been closed.  In barrier-reefs,
therefore, the breaches kept open by draining the tidal waters of the
lagoon-channel, will generally be placed on the leeward side, and they will
still face the mouths of the larger streams, although removed beyond the
influence of their sediment and fresh water;--and this, it has been shown,
is commonly the case.

Referring to the diagram shown above, in which the newly formed barrier-reef
is represented by unbroken lines, instead of by dots as in the former
woodcut, let the work of subsidence go on, and the doubly pointed hill will
form two small islands (or more, according to the number of the hills)
included within one annular reef.  Let the island continue subsiding, and
the coral-reef will continue growing up on its own foundation, whilst the
water gains inch by inch on the land, until the last and highest pinnacle
is covered, and there remains a perfect atoll.  A vertical section of this
atoll is shown in the woodcut by the dotted lines;--a ship is anchored in
its lagoon, but islets are not supposed yet to have been formed on the
reef.  The depth of the lagoon and the width and slope of the reef, will
depend on the circumstances just referred to under barrier-reefs.  Any
further subsidence will produce no change in the atoll, except perhaps a
diminution in its size, from the reef not growing vertically upwards; but
should the currents of the sea act violently upon it, and should the corals
perish on part or on the whole of its margin, changes would result during
subsidence which will be presently noticed.  I may here observe, that a
bank either of rock or of hardened sediment, level with the surface of the
sea, and fringed with living coral, would (if not so small as to allow the
central space to be quickly filled up with detritus) by subsidence be
converted immediately into an atoll, without passing, as in the case of a
reef fringing the shore of an island, through the intermediate form of a
barrier-reef.  If such a bank lay a few fathoms submerged, the simple
growth of the coral (as remarked in the third chapter) without the aid of
subsidence, would produce a structure scarcely to be distinguished from a
true atoll; for in all cases the corals on the outer margin of a reef, from
having space and being freely exposed to the open sea, will grow vigorously
and tend to form a continuous ring whilst the growth of the less massive
kinds on the central expanse, will be checked by the sediment formed there,
and by that washed inwards by the breakers; and as the space becomes
shallower, their growth will, also, be checked by the impurities of the
water, and probably by the small amount of food brought by the enfeebled
currents, in proportion to the surface of living reefs studded with
innumerable craving mouths: the subsidence of a reef based on a bank of
this kind, would give depth to its central expanse or lagoon, steepness to
its flanks, and through the free growth of the coral, symmetry to its
outline:--I may here repeat that the larger groups of atolls in the Pacific
and Indian Oceans cannot be supposed to be founded on banks of this nature.

If, instead of the island in the diagram, the shore of a continent fringed
by a reef had subsided, a great barrier-reef, like that on the north-east
coast of Australia, would have necessarily resulted; and it would have been
separated from the main land by a deep-water channel, broad in proportion
to the amount of subsidence, and to the less or greater inclination of the
neighbouring coast-line.  The effect of the continued subsidence of a great
barrier-reef of this kind, and its probable conversion into a chain of
separate atolls, will be noticed, when we discuss the apparent progressive
disseverment of the larger Maldiva atolls.

We now are able to perceive that the close similarity in form, dimensions,
structure, and relative position (which latter point will hereafter be more
fully noticed) between fringing and encircling barrier-reefs, and between
these latter and atolls, is the necessary result of the transformation,
during subsidence of the one class into the other.  On this view, the three
classes of reefs ought to graduate into each other.  Reefs having
intermediate character between those of the fringing and barrier classes do
exist; for instance, on the south-west coast of Madagascar, a reef extends
for several miles, within which there is a broad channel from seven to
eight fathoms deep, but the sea does not deepen abruptly outside the reef.
Such cases, however, are open to some doubts, for an old fringing-reef,
which had extended itself a little on a basis of its own formation, would
hardly be distinguishable from a barrier-reef, produced by a small amount
of subsidence, and with its lagoon-channel nearly filled up with sediment
during a long stationary period.  Between barrier-reefs, encircling either
one lofty island or several small low ones, and atolls including a mere
expanse of water, a striking series can be shown: in proof of this, I need
only refer to the first plate in this volume, which speaks more plainly to
the eye, than any description could to the ear.  The authorities from which
the charts have been engraved, together with some remarks on them and
descriptive of the plates, are given above.  At New Caledonia (Plate II.,
Figure 5.) the barrier-reefs extend for 150 miles on each side of the
submarine prolongation of the island; and at their northern extremity they
appear broken up and converted into a vast atoll-formed reef, supporting a
few low coral-islets: we may imagine that we here see the effects of
subsidence actually in progress, the water always encroaching on the
northern end of the island, towards which the mountains slope down, and the
reefs steadily building up their massive fabrics in the lines of their
ancient growth.

We have as yet only considered the origin of barrier-reefs and atolls in
their simplest form; but there remain some peculiarities in structure and
some special cases, described in the two first chapters, to be accounted
for by our theory.  These consist--in the inclined ledge terminated by a
wall, and sometimes succeeded by a second ledge with a wall, round the
shores of certain lagoons and lagoon-channels; a structure which cannot, as
I endeavoured to show, be explained by the simple growing powers of the
corals,--in the ring or basin-like forms of the central reefs, as well as
of the separate marginal portions of the northern Maldiva atolls,--in the
submerged condition of the whole, or of parts of certain barrier and
atoll-formed reefs; where only a part is submerged, this being generally to
leeward,--in the apparent progressive disseverment of some of the Maldiva
atolls,--in the existence of irregularly formed atolls, some being tied
together by linear reefs, and others with spurs projecting from them,--and,
lastly, in the structure and origin of the Great Chagos Bank.

STEP-FORMED LEDGES ROUND CERTAIN LAGOONS.

If we suppose an atoll to subside at an extremely slow rate, it is
difficult to follow out the complex results.  The living corals would grow
up on the outer margin; and likewise probably in the gullies and deeper
parts of the bare surface of the annular reef; the water would encroach on
the islets, but the accumulation of fresh detritus might possibly prevent
their entire submergence.  After a subsidence of this very slow nature, the
surface of the annular reef sloping gently into the lagoon, would probably
become united with the irregular reefs and banks of sand, which line the
shores of most lagoons.  Should, however, the atoll be carried down by a
more rapid movement, the whole surface of the annular reef, where there was
a foundation of solid matter, would be favourably circumstanced for the
fresh growth of coral; but as the corals grew upwards on its exterior
margin, and the waves broke heavily on this part, the increase of the
massive polypifers on the inner side would be checked from the want of
water.  Consequently, the exterior parts would first reach the surface, and
the new annular reef thus formed on the old one, would have its summit
inclined inwards, and be terminated by a subaqueous wall, formed by the
upward growth of the coral (before being much checked), from the inner edge
of the solid parts of the old reef.  The inner portion of the new reef,
from not having grown to the surface, would be covered by the waters of the
lagoon.  Should a subsidence of the same kind be repeated, the corals would
again grow up in a wall, from all the solid parts of the resunken reef,
and, therefore, not from within the sandy shores of the lagoon; and the
inner part of the new annular reef would, from being as before checked in
its upward growth, be of less height than the exterior parts, and therefore
would not reach the surface of the lagoon.  In this case the shores of the
lagoon would be surrounded by two inclined ledges, one beneath the other,
and both abruptly terminated by subaqueous cliffs.  (According to Mr.
Couthouy (page 26) the external reef round many atolls descends by a
succession of ledges or terraces.  He attempts, I doubt whether
successfully, to explain this structure somewhat in the same manner as I
have attempted, with respect to the internal ledges round the lagoons of
some atolls.  More facts are wanted regarding the nature both of the
interior and exterior step-like ledges: are all the ledges, or only the
upper ones, covered with living coral?  If they are all covered, are the
kinds different on the ledges according to the depth?  Do the interior and
exterior ledges occur together in the same atolls; if so, what is their
total width, and is the intervening surface-reef narrow, etc.?)

THE RING OR BASIN-FORMED REEFS OF THE NORTHERN MALDIVA ATOLLS.

I may first observe, that the reefs within the lagoons of atolls and within
lagoon-channels, would, if favourably circumstanced, grow upwards during
subsidence in the same manner as the annular rim; and, therefore, we might
expect that such lagoon-reefs, when not surrounded and buried by an
accumulation of sediment more rapid than the rate of subsidence, would rise
abruptly from a greater depth than that at which the efficient polypifers
can flourish: we see this well exemplified in the small abruptly-sided
reefs, with which the deep lagoons of the Chagos and Southern Maldiva
atolls are studded.  With respect to the ring or basin-formed reefs of the
Northern Maldiva atolls, it is evident, from the perfectly continuous
series which exists that the marginal rings, although wider than the
exterior or bounding reef of ordinary atolls, are only modified portions of
such a reef; it is also evident that the central rings, although wider than
the knolls or reefs which commonly occur in lagoons, occupy their place.
The ring-like structure has been shown to be contingent on the breaches
into the lagoon being broad and numerous, so that all the reefs which are
bathed by the waters of the lagoon are placed under nearly the same
conditions with the outer coast of an atoll standing in the open sea.
Hence the exterior and living margins of these reefs must have been
favourably circumstanced for growing outwards, and increasing beyond the
usual breadth; and they must likewise have been favourably circumstanced
for growing vigorously upwards, during the subsiding movements, to which by
our theory the whole archipelago has been subjected; and subsidence with
this upward growth of the margins would convert the central space of each
little reef into a small lagoon.  This, however, could only take place with
those reefs, which had increased to a breadth sufficient to prevent their
central spaces from being almost immediately filled up with the sand and
detritus driven inwards from all sides: hence it is that few reefs, which
are less than half a mile in diameter, even in the atolls where the
basin-like structure is most strikingly exhibited, include lagoons.  This
remark, I may add, applies to all coral-reefs wherever found.  The
basin-formed reefs of the Maldiva Archipelago may, in fact, be briefly
described, as small atolls formed during subsidence over the separate
portions of large and broken atolls, in the same manner as these latter were
formed over the barrier-reefs, which encircled the islands of a large
archipelago now wholly submerged.

SUBMERGED AND DEAD REEFS.

In the second section of the first chapter, I have shown that there are in
the neighbourhood of atolls, some deeply submerged banks, with level
surfaces; that there are others, less deeply but yet wholly submerged,
having all the characters of perfect atolls, but consisting merely of dead
coral-rock; that there are barrier-reefs and atolls with merely a portion
of their reef, generally on the leeward side, submerged; and that such
portions either retain their perfect outline, or they appear to be quite
effaced, their former place being marked only by a bank, conforming in
outline with that part of the reef which remains perfect.  These several
cases are, I believe, intimately related together, and can be explained by
the same means.  There, perhaps, exist some submerged reefs, covered with
living coral and growing upwards, but to these I do not here refer.

As we see that in those parts of the ocean, where coral-reefs are most
abundant, one island is fringed and another neighbouring one is not
fringed; as we see in the same archipelago, that all the reefs are more
perfect in one part of it than in another, for instance, in the southern
half compared with the northern half of the Maldiva Archipelago, and
likewise on the outer coasts compared with the inner coasts of the atolls
in this same group, which are placed in a double row; as we know that the
existence of the innumerable polypifers forming a reef, depends on their
sustenance, and that they are preyed on by other organic beings; and,
lastly, as we know that some inorganic causes are highly injurious to the
growth of coral, it cannot be expected that during the round of change to
which earth, air, and water are exposed, the reef-building polypifers
should keep alive for perpetuity in any one place; and still less can this
be expected, during the progressive subsidences, perhaps at some periods
more rapid than at others, to which by our theory these reefs and islands
have been subjected and are liable.  It is, then, not improbable that the
corals should sometimes perish either on the whole or on part of a reef; if
on part, the dead portion, after a small amount of subsidence, would still
retain its proper outline and position beneath the water.  After a more
prolonged subsidence, it would probably form, owing to the accumulation of
sediment, only the margin of a flat bank, marking the limits of the former
lagoon.  Such dead portions of reef would generally lie on the leeward side
(Mr. Lyell, in the first edition of his "Principles of Geology," offered a
somewhat different explanation of this structure.  He supposes that there
has been subsidence; but he was not aware that the submerged portions of
reef were in most cases, if not in all, dead; and he attributes the
difference in height in the two sides of most atolls, chiefly to the
greater accumulation of detritus to windward than to leeward.  But as
matter is accumulated only on the backward part of the reef, the front part
would remain of the same height on both sides.  I may here observe that in
most cases (for instance, at Peros Banhos, the Gambier group and the Great
Chagos Bank), and I suspect in all cases, the dead and submerged portions
do not blend or slope into the living and perfect parts, but are separated
from them by an abrupt line.  In some instances small patches of living
reef rise to the surface from the middle of the submerged and dead parts.),
for the impure water and fine sediment would more easily flow out from the
lagoon over this side of the reef, where the force of the breakers is less
than to windward; and therefore the corals would be less vigorous on this
side, and be less able to resist any destroying agent.  It is likewise
owing to this same cause, that reefs are more frequently breached to
leeward by narrow channels, serving as by ship-channels, than to windward.
If the corals perished entirely, or on the greater part of the
circumference of an atoll, an atoll-shaped bank of dead rock, more or less
entirely submerged, would be produced; and further subsidence, together
with the accumulation of sediment, would often obliterate its atoll-like
structure, and leave only a bank with a level surface.

In the Chagos group of atolls, within an area of 160 miles by 60, there are
two atoll-formed banks of dead rock (besides another very imperfect one),
entirely submerged; a third, with merely two or three very small pieces of
living reef rising to the surface; and a fourth, namely, Peros Banhos
(Plate I., Figure 9), with a portion nine miles in length dead and
submerged.  As by our theory this area has subsided, and as there is
nothing improbable in the death, either from changes in the state of the
surrounding sea or from the subsidence being great or sudden, of the corals
on the whole, or on portions of some of the atolls, the case of the Chagos
group presents no difficulty.  So far indeed are any of the above-mentioned
cases of submerged reefs from being inexplicable, that their occurrence
might have been anticipated on our theory, and as fresh atolls are supposed
to be in progressive formation by the subsidence of encircling barrier-reefs,
a weighty objection, namely that the number of atolls must be
increasing infinitely, might even have been raised, if proofs of the
occasional destruction and loss of atolls could not have been adduced.

THE DISSEVERMENT OF THE LARGER MALDIVA ATOLLS.

The apparent progressive disseverment in the Maldiva Archipelago of large
atolls into smaller ones, is, in many respects, an important consideration,
and requires an explanation.  The graduated series which marks, as I
believe, this process, can be observed only in the northern half of the
group, where the atolls have exceedingly imperfect margins, consisting of
detached basin-formed reefs.  The currents of the sea flow across these
atolls, as I am informed by Captain Moresby, with considerable force, and
drift the sediment from side to side during the monsoons, transporting much
of it seaward; yet the currents sweep with greater force round their
flanks.  It is historically known that these atolls have long existed in
their present state; and we can believe, that even during a very slow
subsidence they might thus remain, the central expanse being kept at nearly
its original depth by the accumulation of sediment.  But in the action of
such nicely balanced forces during a progressive subsidence (like that, to
which by our theory this archipelago has been subjected), it would be
strange if the currents of the sea should never make a direct passage
across some one of the atolls, through the many wide breaches in their
margins.  If this were once effected, a deep-water channel would soon be
formed by the removal of the finer sediment, and the check to its further
accumulation; and the sides of the channel would be worn into a slope like
that on the outer coasts, which are exposed to the same force of the
currents.  In fact, a channel precisely like that bifurcating one which
divides Mahlos Mahdoo (Plate II., Figure 4.), would almost necessarily be
formed.  The scattered reefs situated near the borders of the new
ocean-channel, from being favourably placed for the growth of coral, would,
by their extension, tend to produce fresh margins to the dissevered portions;
such a tendency is very evident (as may be seen in the large published
chart) in the elongated reefs on the borders of the two channels
intersecting Mahlos Mahdoo.  Such channels would become deeper with
continued subsidence, and probably from the reefs not growing up
perpendicularly, somewhat broader.  In this case, and more especially if
the channels had been formed originally of considerable breadth, the
dissevered portions would become perfect and distinct atolls, like Ari and
Ross atolls (Plate II., Figure 6), or like the two Nillandoo atolls, which
must be considered as distinct, although related in form and position, and
separated from each other by channels, which though deep have been sounded.
Further subsidence would render such channels unfathomable, and the
dissevered portions would then resemble Phaleedoo and Moluque atolls, or
Mahlos Mahdoo and Horsburgh atolls (Plate II., Figure 4), which are related
to each other in no respect except in proximity and position.  Hence, on
the theory of subsidence, the disseverment of large atolls, which have
imperfect margins (for otherwise their disseverment would be scarcely
possible), and which are exposed to strong currents, is far from being an
improbable event; and the several stages, from close relation to entire
isolation in the atolls of the Maldiva Archipelago, are readily explicable.

We might go even further, and assert as not improbable, that the first
formation of the Maldiva Archipelago was due to a barrier-reef, of nearly
the same dimensions with that of New Caledonia (Plate II., Figure 5), for
if, in imagination, we complete the subsidence of that great island, we
might anticipate from the present broken condition of the northern portion
of the reef, and from the almost entire absence of reefs on the eastern
coast, that the barrier-reef after repeated subsidences, would become
during its upward growth separated into distinct portions; and these
portions would tend to assume an atoll-like structure, from the coral
growing with vigour round their entire circumferences, when freely exposed
to an open sea.  As we have some large islands partly submerged with
barrier-reefs marking their former limits, such as New Caledonia, so our
theory makes it probable that there should be other large islands wholly
submerged; and these, we may now infer, would be surmounted, not by one
enormous atoll, but by several large elongated ones, like the atolls in the
Maldiva group; and these again, during long periods of subsidence, would
sometimes become dissevered into smaller atolls.  I may add, that both in
the Marshall and Caroline Archipelagoes, there are atolls standing close
together, which have an evident relationship in form: we may suppose, in
such cases, either that two or more encircled islands originally stood
close together, and afforded bases for two or more atolls, or that one
atoll has been dissevered.  From the position, as well as form, of three
atolls in the Caroline Archipelago (the Namourrek and Elato group), which
are placed in an irregular circle, I am strongly tempted to believe that
they have originated by the process of disseverment.  (The same remark is,
perhaps, applicable to the islands of Ollap, Fanadik, and Tamatam in the
Caroline Archipelago, of which charts are given in the atlas of Duperrey's
voyage: a line drawn through the linear reefs and lagoons of these three
islands forms a semicircle.  Consult also, the atlas of Lutke's voyage; and
for the Marshall group that of Kotzebue; for the Gilbert group consult the
atlas of Duperrey's voyage.  Most of the points here referred to may,
however, be seen in Krusenstern's general Atlas of the Pacific.)

IRREGULARLY FORMED ATOLLS.

In the Marshall group, Musquillo atoll consists of two loops united in one
point; and Menchikoff atoll is formed of three loops, two of which (as may
be seen in Figure 3, Plate II.) are connected by a mere ribbon-shaped reef,
and the three together are sixty miles in length.  In the Gilbert group
some of the atolls have narrow strips of reef, like spurs, projecting from
them.  There occur also in parts of the open sea, a few linear and straight
reefs, standing by themselves; and likewise some few reefs in the form of
crescents, with their extremities more or less curled inwards.  Now, the
upward growth of a barrier-reef which fronted only one side of an island,
or one side of an elongated island with its extremities (of which cases
exist), would produce after the complete subsidence of the land, mere
strips or crescent or hook-formed reefs: if the island thus partially
fronted became divided during subsidence into two or more islands, these
islands would be united together by linear reefs; and from the further
growth of the coral along their shores together with subsidence, reefs of
various forms might ultimately be produced, either atolls united together
by linear reefs, or atolls with spurs projecting from them.  Some, however,
of the more simple forms above specified, might, as we have seen, be
equally well produced by the coral perishing during subsidence on part of
the circumference of an atoll, whilst on the other parts it continued to
grow up till it reached the surface.

THE GREAT CHAGOS BANK.

I have already shown that the submerged condition of the Great Chagos Bank
(Plate II., Figure 1, with its section Figure 2), and of some other banks
in the Chagos group, may in all probability be attributed to the coral
having perished before or during the movements of subsidence, to which this
whole area by our theory has been subjected.  The external rim or upper
ledge (shaded in the chart), consists of dead coral-rock thinly covered
with sand; it lies at an average depth of between five and eight fathoms,
and perfectly resembles in form the annular reef of an atoll.  The banks of
the second level, the boundaries of which are marked by dotted lines in the
chart, lie from about fifteen to twenty fathoms beneath the surface; they
are several miles broad, and terminate in a very steep slope round the
central expanse.  This central expanse I have already described, as
consisting of a level muddy flat between thirty and forty fathoms deep.
The banks of the second level, might at first sight be thought analogous to
the internal step-like ledge of coral-rock which borders the lagoons of
some atolls, but their much greater width, and their being formed of sand,
are points of essential difference.  On the eastern side of the atoll some
of the banks are linear and parallel, resembling islets in a great river,
and pointed directly towards a great breach on the opposite side of the
atoll; these are best seen in the large published chart.  I inferred from
this circumstance, that strong currents sometimes set directly across this
vast bank; and I have since heard from Captain Moresby that this is the
case.  I observed, also, that the channels or breaches through the rim,
were all of the same depth as the central lagoon-like space into which they
lead; whereas the channels into the other atolls of the Chagos group, and
as I believe into most other large atolls, are not nearly as deep as their
lagoons: for instance at Peros Banhos, the channels are only of the same
depth, namely between ten and twenty fathoms, as the bottom of the lagoon
for a space about a mile and a half in width round its shores, whilst the
central expanse of the lagoon is from thirty-five to forty fathoms deep.
Now, if an atoll during a gradual subsidence once became entirely
submerged, like the Great Chagos Bank, and therefore no longer exposed to
the surf, very little sediment could be formed from it; and consequently
the channels leading into the lagoon from not being filled up with drifted
sand and coral detritus, would continue increasing in depth, as the whole
sank down.  In this case, we might expect that the currents of the open
sea, instead of any longer sweeping round the submarine flanks, would flow
directly through the breaches across the lagoon, removing in their course
the finer sediment, and preventing its further accumulation.  We should
then have the submerged reef forming an external and upper rim of rock, and
beneath this portion of the sandy bottom of the old lagoon, intersected by
deep-water channels or breaches, and thus formed into separate marginal
banks; and these would be cut off by steep slopes, overhanging the central
space, worn down by the passage of the oceanic currents.

By these means, I have scarcely any doubt that the Great Chagos Bank has
originated,--a structure which at first appeared to me far more anomalous
than any I had met with.  The process of formation is nearly the same with
that, by which Mahlos Mahdoo had been trisected; but in the Chagos Bank the
channels of the oceanic currents entering at several different quarters,
have united in a central space.

This great atoll-formed bank appears to be in an early stage of
disseverment; should the work of subsidence go on, from the submerged and
dead condition of the whole reef, and the imperfection of the south-east
quarter a mere wreck would probably be left.  The Pitt's Bank, situated not
far southward, appears to be precisely in this state; it consists of a
moderately level, oblong bank of sand, lying from 10 to 20 fathoms beneath
the surface, with two sides protected by a narrow ledge of rock which is
submerged between 5 and 8 fathoms.  A little further south, at about the
same distance as the southern rim of the Great Chagos Bank is from the
northern rim, there are two other small banks with from 10 to 20 fathoms on
them; and not far eastward soundings were struck on a sandy bottom, with
between 110 and 145 fathoms.  The northern portion with its ledge-like
margin, closely resembles any one segment of the Great Chagos Bank, between
two of the deep-water channels, and the scattered banks, southward appear
to be the last wrecks of less perfect portions.

I have examined with care the charts of the Indian and Pacific Oceans, and
have now brought before the reader all the examples, which I have met with,
of reefs differing from the type of the class to which they belong; and I
think it has been satisfactorily shown, that they are all included in our
theory, modified by occasional accidents which might have been anticipated
as probable.  In this course we have seen, that in the lapse of ages
encircling barrier-reefs are occasionally converted into atolls, the name
of atoll being properly applicable, at the moment when the last pinnacle of
encircled land sinks beneath the surface of the sea.  We have, also, seen
that large atolls during the progressive subsidence of the areas in which
they stand, sometimes become dissevered into smaller ones; at other times,
the reef-building polypifers having entirely perished, atolls are converted
into atoll-formed banks of dead rock; and these again through further
subsidence and the accumulation of sediment modified by the force of the
oceanic currents, pass into level banks with scarcely any distinguishing
character.  Thus may the history of an atoll be followed from its first
origin, through the occasional accidents of its existence, to its
destruction and final obliteration.

OBJECTIONS TO THE THEORY OF THE FORMATION OF ATOLLS AND BARRIER-REEFS.

The vast amount of subsidence, both horizontally or in area, and vertically
or in depth, necessary to have submerged every mountain, even the highest,
throughout the immense spaces of ocean interspersed with atolls, will
probably strike most people as a formidable objection to my theory.  But as
continents, as large as the spaces supposed to have subsided, have been
raised above the level of the sea,--as whole regions are now rising, for
instance, in Scandinavia and South America,--and as no reason can be
assigned, why subsidences should not have occurred in some parts of the
earth's crust on as great a scale both in extent and amount as those of
elevation, objections of this nature strike me as of little force.  The
remarkable point is that movements to such an extent should have taken
place within a period, during which the polypifers have continued adding
matter on and above the same reefs.  Another and less obvious objection to
the theory will perhaps be advanced from the circumstance, of the lagoons
within atolls and within barrier-reefs never having become in any one
instance during prolonged subsidences of a greater depth than sixty
fathoms, and seldom more than forty fathoms; but we already admit, if the
theory be worth considering, that the rate of subsidence has not exceeded
that of the upward growth of the coral on the exterior margin; we are,
therefore, only further required to admit, that the subsidence has not
exceeded in rate the filling up of the interior spaces by the growth of the
corals living there, and by the accumulation of sediment.  As this filling
up must take place very slowly within barrier-reefs lying far from the
land, and within atolls which are of large dimensions and which have open
lagoons with very few reefs, we are led to conclude that the subsidence
thus counter-balanced, must have been slow in an extraordinary degree; a
conclusion which accords with our only means, namely, with what is known of
the rate and manner of recent elevatory movements, of judging by analogy
what is the probable rate of subsidence.

In this chapter it has, I think, been shown, that the theory of subsidence,
which we were compelled to receive from the necessity of giving to the
corals, in certain large areas, foundations at the requisite depth,
explains both the normal structure and the less regular forms of those two
great classes of reefs, which have justly excited the astonishment of all
persons who have sailed through the Pacific and Indian Oceans.  But further
to test the truth of the theory, a crowd of questions will occur to the
reader: Do the different kinds of reefs, which have been produced by the
same kind of movement, generally lie within the same areas?  What is their
relation of form and position,--for instance, do adjoining groups of
atolls, and the separate atolls in these groups, bear the same relation to
each other which islands do in common archipelagoes?  Have we reason to
believe, that where there are fringing-reefs, there has not lately been
subsidence; or, for it is almost our only way of ascertaining this point,
are there frequently proofs of recent elevation?  Can we by this means
account for the presence of certain classes of reefs in some large areas,
and their entire absence in others?  Do the areas which have subsided, as
indicated by the presence of atolls and barrier-reefs, and the areas which
have remained stationary or have been upraised, as shown by fringing-reefs,
bear any determinate relation to each other; and are the dimensions of
these areas such as harmonise with the greatness of the subterranean
changes, which, it must be supposed, have lately taken place beneath them?
Is there any connection between the movements thus indicated, and recent
volcanic action?  All these questions ought to receive answers in
accordance with the theory; and if this can be satisfactorily shown, not
only is the theory confirmed, but as deductions, the answers are in
themselves important.  Under this latter point of view, these questions
will be chiefly considered in the following chapter.

(I may take this opportunity of briefly considering the appearances, which
would probably be presented by a vertical and deep section across a coral
formation (referring chiefly to an atoll), formed by the upward growth of
coral during successive subsidences.  This is a subject worthy of
attention, as a means of comparison with ancient coral-strata.  The
circumferential parts would consist of massive species, in a vertical
position, with their interstices filled up with detritus; but this would be
the part most subject to subsequent denudation and removal.  It is useless
to speculate how large a portion of the exterior annular reef would consist
of upright coral, and how much of fragmentary rock, for this would depend
on many contingencies,--such as on the rate of subsidence, occasionally
allowing a fresh growth of coral to cover the whole surface, and on the
breakers having force sufficient to throw fragments over this same space.
The conglomerate which composes the base of the islets, would (if not
removed by denudation together with the exterior reef on which it rests) be
conspicuous from the size of the fragments,--the different degrees in which
they have been rounded,--the presence of fragments of conglomerate torn up,
rounded, and recemented,--and from the oblique stratification.  The corals
which lived in the lagoon-reefs at each successive level, would be
preserved upright, and they would consist of many kinds, generally much
branched.  In this part, however, a very large proportion of the rock (and
in some cases nearly all of it) would be formed of sedimentary matter,
either in an excessively fine, or in a moderately coarse state, and with
the particles almost blended together.  The conglomerate which was formed
of rounded pieces of the branched corals, on the shores of the lagoon,
would differ from that formed on the islets and derived from the outer
coast; yet both might have accumulated very near each other.  I have seen a
conglomerate limestone from Devonshire like a conglomerate now forming on
the shores of the Maldiva atolls.  The stratification taken as a whole,
would be horizontal; but the conglomerate beds resting on the exterior
reef, and the beds of sandstone on the shores of the lagoon (and no doubt
on the external flanks) would probably be divided (as at Keeling atoll and
at Mauritius) by numerous layers dipping at considerable angles in
different directions.  The calcareous sandstone and coral-rock would almost
necessarily contain innumerable shells, echini, and the bones of fish,
turtle, and perhaps of birds; possibly, also, the bones of small saurians,
as these animals find their way to the islands far remote from any
continent.  The large shells of some species of Tridacna would be found
vertically imbedded in the solid rock, in the position in which they lived.
We might expect also to find a mixture of the remains of pelagic and
littoral animals in the strata formed in the lagoon, for pumice and the
seeds of plants are floated from distant countries into the lagoons of many
atolls: on the outer coast of Keeling atoll, near the mouth of the lagoon,
the case of a pelagic Pteropodous animal was brought up on the arming of
the sounding lead.  All the loose blocks of coral on Keeling atoll were
burrowed by vermiform animals; and as every cavity, no doubt, ultimately
becomes filled with spathose limestone, slabs of the rock taken from a
considerable depth, would, if polished, probably exhibit the excavations of
such burrowing animals.  The conglomerate and fine-grained beds of coral-rock
would be hard, sonorous, white and composed of nearly pure calcareous
matter; in some few parts, judging from the specimens at Keeling atoll,
they would probably contain a small quantity of iron.  Floating pumice and
scoriae, and occasionally stones transported in the root of trees (see my
"Journal of Researches," page 549) appear the only sources, through which
foreign matter is brought to coral-formations standing in the open ocean.
The area over which sediment is transported from coral-reefs must be
considerable: Captain Moresby informs me that during the change of
monsoons the sea is discoloured to a considerable distance off the Maldiva
and Chagos atolls.  The sediment of fringing and barrier coral-reefs must
be mingled with the mud, which is brought down from the land, and is
transported seaward through the breaches, which occur in front of almost
every valley.  If the atolls of the larger archipelagoes were upraised, the
bed of the ocean being converted into land, they would form flat-topped
mountains, varying in diameter from a few miles (the smallest atolls being
worn away) to sixty miles; and from being horizontally stratified and of
similar composition, they would, as Mr. Lyell has remarked, falsely appear
as if they had originally been united into one vast continuous mass.  Such
great strata of coral-rock would rarely be associated with erupted volcanic
matter, for this could only take place, as may be inferred from what
follows in the next chapter, when the area, in which they were situated,
commenced to rise, or at least ceased to subside.  During the enormous
period necessary to effect an elevation of the kind just alluded to, the
surface would necessarily be denuded to a great thickness; hence it is
highly improbable that any fringing-reef, or even any barrier-reef, at
least of those encircling small islands, would be preserved.  From this
same cause, the strata which were formed within the lagoons of atolls and
lagoon-channels of barrier-reefs, and which must consist in a large part of
sedimentary matter, would more often be preserved to future ages, than the
exterior solid reef, composed of massive corals in an upright position;
although it is on this exterior part that the present existence and further
growth of atolls and barrier-reefs entirely depend.


CHAPTER VI.--ON THE DISTRIBUTION OF CORAL-REEFS WITH REFERENCE TO THE
THEORY OF THEIR FORMATION.

(DESCRIPTION OF THE PLATES.

PLATE III.--MAP SHOWING THE DISTRIBUTION OF CORAL-REEFS AND ACTIVE
VOLCANOES.

The principles, on which this map was coloured, are explained in the
beginning of Chapter VI.; and the authorities for each particular spot are
detailed in the Appendix to "Coral Reefs."  The names not printed in upper
case in the Index refer to the Appendix.)

Description of the coloured map.--Proximity of atolls and barrier-reefs.--
Relation in form and position of atolls with ordinary islands.--Direct
evidence of subsidence difficult to be detected.--Proofs of recent
elevation where fringing-reefs occur.--Oscillations of level.--Absence of
active volcanoes in the areas of subsidence.--Immensity of the areas which
have been elevated and have subsided.--Their relation to the present
distribution of the land.--Areas of subsidence elongated, their
intersection and alternation with those of elevation.--Amount and slow rate
of the subsidence.--Recapitulation.

It will be convenient to give here a short account of the appended map
(Plate III.)  [Inasmuch as the coloured map would have proved too costly to
be given in this series, the indications of colour have been replaced by
numbers referring to the dotted groups of reefs, etc.  The author's
original wording, however, is retained in full, as it will be easy to refer
to the map by the numbers, and thus the flow of the narrative is
undisturbed.]: a fuller one, with the data for colouring each spot, is
reserved for the Appendix; and every place there referred to may be found
in the Index.  A larger chart would have been desirable; but, small as the
adjoined one is, it is the result of many months' labour.  I have
consulted, as far as I was able, every original voyage and map; and the
colours were first laid down on charts on a larger scale.  The same blue
colour, with merely a difference in the depth of tint, is used for atolls
or lagoon-islands, and barrier-reefs, for we have seen, that as far as the
actual coral-formation is concerned, they have no distinguishing character.
Fringing-reefs have been coloured red, for between them on the one hand,
and barrier-reefs and atolls on the other, there is an important
distinction with respect to the depth beneath the surface, at which we are
compelled to believe their foundations lie.  The two distinct colours,
therefore, mark two great types of structure.

The DARK BLUE COLOUR [represented by (3) in our plate] represents atolls
and submerged annular reefs, with deep water in their centres.  I have
coloured as atolls, a few low and small coral-islands, without lagoons; but
this has been done only when it clearly appeared that they originally
contained lagoons, since filled up with sediment: when there were not good
grounds for this belief, they have been left uncoloured.

The PALE BLUE COLOUR [represented by (2)] represents barrier-reefs.  The
most obvious character of reefs of this class is the broad and deep-water
moat within the reef: but this, like the lagoons of small atolls, is
liable to become filled up with detritus and with reefs of delicately
branched corals: when, therefore, a reef round the entire circumference of
an island extends very far into a profoundly deep sea, so that it can
hardly be confounded with a fringing-reef which must rest on a foundation
of rock within a small depth, it has been coloured pale blue, although it
does not include a deep-water moat: but this has only been done rarely,
and each case is distinctly mentioned in the Appendix.

The RED COLOUR (4) represents reefs fringing the land quite closely where
the sea is deep, and where the bottom is gently inclined extending to a
moderate distance from it, but not having a deep-water moat or lagoon-like
space parallel to the shore.  It must be remembered that fringing-reefs are
frequently BREACHED in front of rivers and valleys by deepish channels,
where mud has been deposited.  A space of thirty miles in width has been
coloured round or in front of the reefs of each class, in order that the
colours might be conspicuous on the appended map, which is reduced to so
small a scale.

The VERMILLION SPOTS, and streaks (1) represent volcanoes now in action, or
historically known to have been so.  They are chiefly laid down from Von
Buch's work on the Canary Islands; and my reasons for making a few
alterations are given in the note below.

(I have also made considerable use of the geological part of Berghaus'
"Physical Atlas."  Beginning at the eastern side of the Pacific, I have
added to the number of the volcanoes in the southern part of the
Cordillera, and have coloured Juan Fernandez according to observations
collected during the voyage of the "Beagle" ("Geological Transactions,"
volume v., page 601.)  I have added a volcano to Albemarle Island, one of
the Galapagos Archipelago (the author's "Journal of Researches," page 457).
In the Sandwich group there are no active volcanoes, except at Hawaii; but
the Rev. W. Ellis informs me, there are streams of lava apparently modern
on Maui, having a very recent appearance, which can be traced to the
craters whence they flowed.  The same gentleman informs me, that there is
no reason to believe that any active volcano exists in the Society
Archipelago; nor are there any known in the Samoa or Navigator group,
although some of the streams of lava and craters there appear recent.  In
the Friendly group, the Rev. J. Williams says ("Narrative of Missionary
Enterprise," page 29) that Toofoa and Proby Islands are active volcanoes.
I infer from Hamilton's "Voyage in the 'Pandora'" (Page 95), that Proby
Island is synonymous with Onouafou, but I have not ventured to colour it.
There can be no doubt respecting Toofoa, and Captain Edwards (Von Buch,
page 386) found the lava of recent eruption at Amargura still smoking.
Berghaus marks four active volcanoes actually within the Friendly group;
but I do not know on what authority: I may mention that Maurelle describes
Latte as having a burnt-up appearance: I have marked only Toofoa and
Amargura.  South of the New Hebrides lies Matthews Rock, which is drawn and
described as an active crater in the "Voyage of the 'Astrolabe'."  Between
it and the volcano on the eastern side of New Zealand, lies Brimstone
Island, which from the high temperature of the water in the crater, may be
ranked as active (Berghaus "Vorbemerk," II Lief. S. 56).  Malte Brun,
volume xii., page 231, says that there is a volcano near port St. Vincent
in New Caledonia.  I believe this to be an error, arising from a smoke seen
on the OPPOSITE coast by Cook ("Second Voyage," volume ii., page 23) which
smoke went out at night.  The Mariana Islands, especially the northern
ones, contain many craters (see Freycinet's "Hydrog. Descript.") which are
not active.  Von Buch, however, states (page 462) on the authority of La
Peyrouse, that there are no less than seven volcanoes between these islands
and Japan.  Gemelli Creri (Churchill's "Collect." volume iv., page 458),
says there are two active volcanoes in latitude 23 deg 30', and in latitude
24 deg: but I have not coloured them.  From the statements in Beechey's
"Voyage" (page 518, 4to edition) I have coloured one in the northern part
of the Bonin group.  M. S. Julien has clearly made out from Chinese
manuscripts not very ancient ("Comptes Rendus," 1840, page 832), that there
are two active volcanoes on the eastern side of Formosa.  In Torres
Straits, on Cap Island (9 deg 48' S., 142 deg 39' E.) a volcano was seen
burning with great violence in 1793 by Captain Bampton (see Introduction to
Flinders' "Voyage," page 41).  Mr. M'Clelland (Report of Committee for
investigating Coal in India, page 39) has shown that the volcanic band
passing through Barren Island must be extended northwards.  It appears by
an old chart, that Cheduba was once an active volcano (see also "Silliman's
North American Journal", volume xxxviii., page 385).  In Berghaus'
"Physical Atlas," 1840, No. 7 of Geological Part, a volcano on the coast of
Pondicherry is said to have burst forth in 1757.  Ordinaire ("Hist. Nat.
des Volcans," page 218) says that there is one at the mouth of the Persian
Gulf, but I have not coloured it, as he gives no particulars.  A volcano in
Amsterdam, or St. Paul's, in the southern part of the Indian Ocean, has
been seen ("Naut. Mag." 1838, page 842) in action.  Dr. J. Allan, of
Forres, informs me in a letter, that when he was at Joanna, he saw at night
flames apparently volcanic, issuing from the chief Comoro Island, and that
the Arabs assured him that they were volcanic, adding that the volcano
burned more during the wet season.  I have marked this as a volcano, though
with some hesitation, on account of the possibility of the flame arising
from gaseous sources.)

The uncoloured coasts consist, first and chiefly, of those, where there are
no coral-reefs, or such small portions as to be quite insignificant.
Secondly, of those coasts where there are reefs, but where the sea is very
shallow, for in this case the reefs generally lie far from the land, and
become very irregular, in their forms: where they have not become
irregular, they have been coloured.  thirdly, if I had the means of
ascertaining the fact, I should not colour a reef merely coating the edges
of a submarine crater, or of a level submerged bank; for such superficial
formations differ essentially, even when not in external appearance, from
reefs whose foundations as well as superficies have been wholly formed by
the growth of coral.  Fourthly, in the Red Sea, and within some parts of
the East Indian Archipelago (if the imperfect charts of the latter can be
trusted), there are many scattered reefs, of small size, represented in the
chart by mere dots, which rise out of deep water: these cannot be arranged
under either of the three classes: in the Red Sea, however, some of these
little reefs, from their position, seem once to have formed parts of a
continuous barrier.  There exist, also, scattered in the open ocean, some
linear and irregularly formed strips of coral-reef, which, as shown in the
last chapter, are probably allied in their origin to atolls; but as they do
not belong to that class, they have not been coloured; they are very few in
number and of insignificant dimensions.  Lastly, some reefs are left
uncoloured from the want of information respecting them, and some because
they are of an intermediate structure between the barrier and fringing
classes.  The value of the map is lessened, in proportion to the number of
reefs which I have been obliged to leave uncoloured, although, in a
theoretical point of view, few of them present any great difficulty: but
their number is not very great, as will be found by comparing the map with
the statements in the Appendix.  I have experienced more difficulty in
colouring fringing-reefs than in colouring barrier-reefs, as the former,
from their much less dimensions, have less attracted the attention of
navigators.  As I have had to seek my information from all kinds of
sources, and often from indirect ones, I do not venture to hope that the
map is free from many errors.  Nevertheless, I trust it will give an
approximately correct view of the general distribution of the coral-reefs
over the whole world (with the exception of some fringing-reefs on the
coast of Brazil, not included within the limits of the map), and of their
arrangement into the three great classes, which, though necessarily very
imperfect from the nature of the objects classified, have been adopted by
most voyagers.  I may further remark, that the dark blue colour represents
land entirely composed of coral-rock; the pale blue, land with a wide and
thick border of coral-rock; and the red, a mere narrow fringe of
coral-rock.

Looking now at the map under the theoretical point of view indicated in the
last chapter, the two blue tints signify that the foundations of the reefs
thus coloured have subsided to a considerable amount, at a slower rate than
that of the upward growth of the corals, and that probably in many cases
they are still subsiding.  The red signifies that the shores which support
fringing-reefs have not subsided (at least to any considerable amount, for
the effects of a subsidence on a small scale would in no case be
distinguishable); but that they have remained nearly stationary since the
period when they first became fringed by reefs; or that they are now rising
or have been upraised, with new lines of reefs successively formed on them:
these latter alternatives are obviously implied, as newly formed lines of
shore, after elevations of the land, would be in the same state with
respect to the growth of fringing-reefs, as stationary coasts.  If during
the prolonged subsidence of a shore, coral-reefs grew for the first time on
it, or if an old barrier-reef were destroyed and submerged, and new reefs
became attached to the land, these would necessarily at first belong to the
fringing class, and, therefore, be coloured red, although the coast was
sinking: but I have no reason to believe, that from this source of error,
any coast has been coloured wrongly with respect to movement indicated.
Well characterised atolls and encircling barrier-reefs, where several occur
in a group, or a single barrier-reef if of large dimensions, leave scarcely
any doubt on the mind respecting the movement by which they have been
produced; and even a small amount of subsequent elevation is soon betrayed.
The evidence from a single atoll or a single encircling barrier-reef, must
be received with some caution, for the former may possibly be based upon a
submerged crater or bank, and the latter on a submerged margin of sediment,
or of worn-down rock.  From these remarks we may with greater certainty
infer that the spaces, especially the larger ones, tinted blue in the map,
have subsided, than that the red spaces have remained stationary, or have
been upraised.

ON THE GROUPING OF THE DIFFERENT CLASSES OF REEFS.

Having made these preliminary remarks, I will consider first how far the
grouping of the different kinds of coral-islands and reefs is corroborative
of the truth of the theory.  A glance at the map shows that the reefs,
coloured blue and red, produced under widely different conditions, are not
indiscriminately mixed together.  Atolls and barrier-reefs, on the other
hand, as may be seen by the two blue tints, generally lie near each other;
and this would be the natural result of both having been produced during
the subsidence of the areas in which they stand.  Thus, the largest group
of encircled islands is that of the Society Archipelago; and these islands
are surrounded by atolls, and only separated by a narrow space from the
large group of Low atolls.  In the midst of the Caroline atolls, there are
three fine encircled islands.  The northern point of the barrier-reef of
New Caledonia seems itself, as before remarked, to form a complete large
atoll.  The great Australian barrier is described as including both atolls
and small encircled islands.  Captain King (Sailing directions, appended to
volume ii. of his "Surveying Voyage to Australia.") mentions many
atoll-formed and encircling coral-reefs, some of which lie within the
barrier, and others may be said (for instance between latitude 16 deg and
13 deg) to form part of it.  Flinders ("Voyage to Terra Australis," volume
ii. page 336.) has described an atoll-formed reef in latitude 10 deg, seven
miles long and from one to three broad, resembling a boot in shape, with
apparently very deep water within.  Eight miles westward of this, and
forming part of the barrier, lie the Murray Islands, which are high and are
encircled.  In the Corallian Sea, between the two great barriers of
Australia and New Caledonia, there are many low islets and coral-reefs,
some of which are annular, or horse-shoe shaped.  Observing the smallness
of the scale of the map, the parallels of latitude being nine hundred miles
apart, we see that none of the large groups of reefs and islands supposed
to have been produced by long-continued subsidence, lie near extensive
lines of coast coloured red, which are supposed to have remained stationary
since the growth of their reefs, or to have been upraised and new lines of
reefs formed on them.  Where the red and blue circles do occur near each
other, I am able, in several instances, to show that there have been
oscillations of level, subsidence having preceded the elevation of the red
spots; and elevation having preceded the subsidence of the blue spots: and
in this case the juxtaposition of reefs belonging to the two great types of
structure is little surprising.  We may, therefore, conclude that the
proximity in the same areas of the two classes of reefs, which owe their
origin to the subsidence of the earth's crust, and their separation from
those formed during its stationary or uprising condition, holds good to the
full extent, which might have been anticipated by our theory.

As groups of atolls have originated in the upward growth, at each fresh
sinking of the land, of those reefs which primarily fringed the shores of
one great island, or of several smaller ones; so we might expect that these
rings of coral-rock, like so many rude outline charts, will still retain
some traces of the general form, or at least general range, of the land,
round which they were first modelled.  That this is the case with the
atolls in the Southern Pacific as far as their range is concerned, seems
highly probable, when we observe that the three principal groups are
directed in north-west and south-east lines, and that nearly all the land
in the S. Pacific ranges in this same direction; namely, N. Western
Australia, New Caledonia, the northern half of New Zealand, the New
Hebrides, Saloman, Navigator, Society, Marquesas, and Austral
archipelagoes: in the Northern Pacific, the Caroline atolls abut against
the north-west line of the Marshall atolls, much in the same manner as the
east and west line of islands from Ceram to New Britain do on New Ireland:
in the Indian Ocean the Laccadive and Maldiva atolls extend nearly parallel
to the western and mountainous coast of India.  In most respects, there is
a perfect resemblance with ordinary islands in the grouping of atolls and
in their form: thus the outline of all the larger groups is elongated; and
the greater number of the individual atolls are elongated in the same
direction with the group, in which they stand.  The Chagos group is less
elongated than is usual with other groups, and the individual atolls in it
are likewise but little elongated; this is strikingly seen by comparing
them with the neighbouring Maldiva atolls.  In the Marshall and Maldiva
archipelagoes, the atolls are ranged in two parallel lines, like the
mountains in a great double mountain-chain.  Some of the atolls, in the
larger archipelagoes, stand so near to each other, and have such an evident
relationship in form, that they compose little sub-groups: in the Caroline
Archipelago, one such sub-group consists of Pouynipete, a lofty island
encircled by a barrier-reef, and separated by a channel only four miles and
a half wide from Andeema atoll, with a second atoll a little further off.
In all these respects an examination of a series of charts will show how
perfectly groups of atolls resemble groups of common islands.

ON THE DIRECT EVIDENCE OF THE BLUE SPACES IN THE MAP HAVING SUBSIDED DURING
THE UPWARD GROWTH OF THE REEFS SO COLOURED, AND OF THE RED SPACES HAVING
REMAINED STATIONARY, OR HAVING BEEN UPRAISED.

With respect to subsidence, I have shown in the last chapter, that we
cannot expect to obtain in countries inhabited only by semi-civilised
races, demonstrative proofs of a movement, which invariably tends to
conceal its own evidence.  But on the coral-islands supposed to have been
produced by subsidence, we have proofs of changes in their external
appearance--of a round of decay and renovation--of the last vestiges of
land on some--of its first commencement on others: we hear of storms
desolating them to the astonishment of their inhabitants: we know by the
great fissures with which some of them are traversed, and by the
earthquakes felt under others, that subterranean disturbances of some kind
are in progress.  These facts, if not directly connected with subsidence,
as I believe they are, at least show how difficult it would be to discover
proofs of such movement by ordinary means.  At Keeling atoll, however, I
have described some appearances, which seem directly to show that
subsidence did take place there during the late earthquakes.  Vanikoro,
according to Chevalier Dillon (See Captain Dillon's "Voyage in search of La
Peyrouse."  M. Cordier in his "Report on the Voyage of the 'Astrolabe'"
(page cxi., volume i.), speaking of Vanikoro, says the shores are
surrounded by reefs of madrepore, "qu'on assure etre de formation
tout-a-fait moderne."  I have in vain endeavoured to learn some further
particulars about this remarkable passage.  I may here add, that according
to our theory, the island of Pouynipete (Plate I., Figure 7), in the
Caroline Archipelago, being encircled by a barrier-reef, must have
subsided.  In the "New S. Wales Lit. Advert." February 1835 (which I have
seen through the favour of Dr. Lloghtsky), there is an account of this
island (subsequently confirmed by Mr. Campbell), in which it is said, "At
the N.E. end, at a place called Tamen, there are ruins of a town, NOW ONLY
accessible by boats, the waves REACHING TO THE STEPS OF The HOUSES."
Judging from this passage, one would be tempted to conclude that the island
must have subsided, since these houses were built.  I may, also, here
append a statement in Malte Brun (volume ix., page 775, given without any
authority), that the sea gains in an extraordinary manner on the coast of
Cochin China, which lies in front and near the subsiding coral-reefs in the
China Sea: as the coast is granitic, and not alluvial, it is scarcely
possible that the encroachment of the sea can be owing to the washing away
of the land; and if so, it must be due to subsidence.), is often violently
shaken by earthquakes, and there, the unusual depth of the channel between
the shore and the reef,--the almost entire absence of islets on the reef,--
its wall-like structure on the inner side, and the small quantity of low
alluvial land at the foot of the mountains, all seem to show that this
island has not remained long at its present level, with the lagoon-channel
subjected to the accumulation of sediment, and the reef to the wear and
tear of the breakers.  At the Society Archipelago, on the other hand, where
a slight tremor is only rarely felt, the shoaliness of the lagoon-channels
round some of the islands, the number of islets formed on the reefs of
others, and the broad belt of low land at the foot of the mountains,
indicate that, although there must have been great subsidence to have
produced the barrier-reefs, there has since elapsed a long stationary
period.

(Mr. Couthouy states ("Remarks," page 44) that at Tahiti and Eimeo the
space between the reef and the shore has been nearly filled up by the
extension of those coral-reefs, which within most barrier-reefs merely
fringe the land.  From this circumstance, he arrives at the same conclusion
as I have done, that the Society Islands since their subsidence, have
remained stationary during a long period; but he further believes that they
have recently commenced rising, as well as the whole area of the Low
Archipelago.  He does not give any detailed proofs regarding the elevation
of the Society Islands, but I shall refer to this subject in another part
of this chapter.  Before making some further comments, I may observe how
satisfactory it is to me, to find Mr. Couthouy affirming, that "having
personally examined a large number of coral-islands, and also residing
eight months among the volcanic class, having shore and partially
encircling reefs, I may be permitted to state that my own observations have
impressed a conviction of the correctness of the theory of Mr. Darwin."

This gentleman believes, that subsequently to the subsidence by which the
atolls in the Low Archipelago were produced, the whole area has been
elevated to the amount of a few feet; this would indeed be a remarkable
fact; but as far as I am able to judge, the grounds of his conclusion are
not sufficiently strong.  He states that he found in almost every atoll
which he visited, the shores of the lagoon raised from eighteen to thirty
inches above the sea-level, and containing imbedded Tridacnae and corals
standing as they grew; some of the corals were dead in their upper parts,
but below a certain line they continued to flourish.  In the lagoons, also,
he frequently met with clusters of Madrepore, with their extremities
standing from one inch to a foot above the surface of the water.  Now,
these appearances are exactly what I should have expected, without any
subsequent elevation having taken place; and I think Mr. Couthouy has not
borne in mind the indisputable fact, that corals, when constantly bathed by
the surf, can exist at a higher level than in quite tranquil water, as in a
lagoon.  As long, therefore, as the waves continued at low water to break
entirely over parts of the annular reef of an atoll, submerged to a small
depth, the corals and shells attached on these parts might continue living
at a level above the smooth surface of the lagoon, into which the waves
rolled; but as soon as the outer edge of the reef grew up to its utmost
possible height, or if the reef were very broad nearly to that height, the
force of the breakers would be checked, and the corals and shells on the
inner parts near the lagoon would occasionally be left dry, and thus be
partially or wholly destroyed.  Even in atolls, which have not lately
subsided, if the outer margin of the reef continued to increase in breadth
seaward (each fresh zone of corals rising to the same vertical height as at
Keeling atoll), the line where the waves broke most heavily would advance
outwards, and therefore the corals, which when living near the margin, were
washed by the breaking waves during the whole of each tide, would cease
being so, and would therefore be left on the backward part of the reef
standing exposed and dead.  The case of the madrepores in the lagoons with
the tops of their branches exposed, seems to be an analogous fact, to the
great fields of dead but upright corals in the lagoon of Keeling atoll; a
condition of things which I have endeavoured to show, has resulted from the
lagoon having become more and more enclosed and choked up with reefs, so
that during high winds, the rising of the tide (as observed by the
inhabitants) is checked, and the corals, which had formerly grown to the
greatest possible height, are occasionally exposed, and thus are killed:
and this is a condition of things, towards which almost every atoll in the
intervals of its subsidence must be tending.  Or if we look to the state of
an atoll directly after a subsidence of some fathoms, the waves would roll
heavily over the entire circumference of the reef, and the surface of the
lagoon would, like the ocean, never be quite at rest, and therefore the
corals in the lagoon, from being constantly laved by the rippling water,
might extend their branches to a little greater height than they could,
when the lagoon became enclosed and protected.  Christmas atoll (2 deg N.
latitude) which has a very shallow lagoon, and differs in several respects
from most atolls, possibly may have been elevated recently; but its highest
part appears (Couthouy, page 46) to be only ten feet above the sea-level.
The facts of a second class, adduced by Mr. Couthouy, in support of the
alleged recent elevation of the Low Archipelago, are not all (especially
those referring to a shelf of rock) quite intelligible to me; he believes
that certain enormous fragments of rock on the reef, must have been moved
into their present position, when the reef was at a lower level; but here
again the force of the breakers on any inner point of the reef being
diminished by its outward growth without any change in its level, has not,
I think, been borne in mind.  We should, also, not overlook the occasional
agency of waves caused by earthquakes and hurricanes.  Mr. Couthouy further
argues, that since these great fragments were deposited and fixed on the
reef, they have been elevated; he infers this from the greatest amount of
erosion not being near their bases, where they are unceasingly washed by
the reflux of the tides, but at some height on their sides, near the line
of high-water mark, as shown in an accompanying diagram.  My former remark
again applies here, with this further observation, that as the waves have
to roll over a wide space of reef before they reach the fragments, their
force must be greatly increased with the increasing depth of water as the
tide rises, and therefore I should have expected that the chief line of
present erosion would have coincided with the line of high-water mark; and
if the reef had grown outwards, that there would have been lines of erosion
at greater heights.  The conclusion, to which I am finally led by the
interesting observations of Mr. Couthouy is, that the atolls in the Low
Archipelago have, like the Society Islands, remained at a stationary level
for a long period: and this probably is the ordinary course of events,
subsidence supervening after long intervals of rest.)

Turning now to the red colour; as on our map, the areas which have sunk
slowly downwards to great depths are many and large, we might naturally
have been led to conjecture, that with such great changes of level in
progress, the coasts which have been fringed probably for ages (for we have
no reason to believe that coral-reefs are of short duration), would not
have remained all this time stationary, but would frequently have undergone
movements of elevation.  This supposition, we shall immediately see, holds
good to a remarkable extent; and although a stationary condition of the
land can hardly ever be open to proof, from the evidence being only
negative, we are, in some degree, enabled to ascertain the correctness of
the parts coloured red on the map, by the direct testimony of upraised
organic remains of a modern date.  Before going into the details on this
head (printed in small type), I may mention, that when reading a memoir on
coral formations by MM. Quoy and Gaimard ("Annales des Sciences Nat." tom.
vi., page 279, etc.) I was astonished to find, for I knew that they had
crossed both the Pacific and Indian Oceans, that their descriptions were
applicable only to reefs of the fringing class; but my astonishment ended
satisfactorily, when I discovered that, by a strange chance, all the
islands which these eminent naturalists had visited, though several in
number, namely, the Mauritius, Timor, New Guinea, the Mariana, and Sandwich
Archipelagoes, could be shown by their own statements to have been elevated
within a recent geological era.

In the eastern half of the Pacific, the SANDWICH Islands are all fringed,
and almost every naturalist who has visited them, has remarked on the
abundance of elevated corals and shells, apparently identical with living
species.  The Rev. W. Ellis informs me, that he has noticed round several
parts of Hawaii, beds of coral-detritus, about twenty feet above the level
of the sea, and where the coast is low they extend far inland.  Upraised
coral-rock forms a considerable part of the borders of Oahu; and at
Elizabeth Island ("Zoology of Captain Beechey's Voyage," page 176.  See
also MM. Quoy and Gaimard in "Annales de Scien. Nat." tom. vi.) it composes
three strata, each about ten feet thick.  Nihau, which forms the northern,
as Hawaii does the southern end of the group (350 miles in length),
likewise seems to consist of coral and volcanic rocks.  Mr. Couthouy
("Remarks on Coral Formations," page 51.) has lately described with
interesting details, several upraised beaches, ancient reefs with their
surfaces perfectly preserved, and beds of recent shells and corals, at the
islands of Maui, Morokai, Oahu, and Tauai (or Kauai) in this group.  Mr.
Pierce, an intelligent resident at Oahu, is convinced, from changes which
have taken place within his memory, during the last sixteen years, "that
the elevation is at present going forward at a very perceptible rate."  The
natives at Kauai state that the land is there gaining rapidly on the sea,
and Mr. Couthouy has no doubt, from the nature of the strata, that this has
been effected by an elevation of the land.

In the southern part of the Low Archipelago, Elizabeth Island is described
by Captain Beechey (Beechey's "Voyage in the Pacific," page 46, 4to
edition.), as being quite flat, and about eighty feet in height; it is
entirely composed of dead corals, forming a honeycombed, but compact rock.
In cases like this, of an island having exactly the appearance, which the
elevation of any one of the smaller surrounding atolls with a shallow
lagoon would present, one is led to conclude (with little better reason,
however, than the improbability of such small and low fabrics lasting, for
an immense period, exposed to the many destroying agents of nature), that
the elevation has taken place at an epoch not geologically remote.  When
merely the surface of an island of ordinary formation is strewed with
marine bodies, and that continuously, or nearly so, from the beach to a
certain height, and not above that height, it is exceedingly improbable
that such organic remains, although they may not have been specially
examined, should belong to any ancient period.  It is necessary to bear
these remarks in mind, in considering the evidence of the elevatory
movements in the Pacific and Indian Oceans, as it does not often rest on
specific determinations, and therefore should be received with caution.
Six of the COOK AND AUSTRAL Islands (S.W. of the Society group), are
fringed; of these, five were described to me by the Rev. J. Williams, as
formed of coral-rock, associated with some basalt in Mangaia), and the
sixth as lofty and basaltic.  Mangaia is nearly three hundred feet high,
with a level summit; and according to Mr. S. Wilson (Couthouy's "Remarks,"
page 34.) it is an upraised reef; "and there are in the central hollow,
formerly the bed of the lagoon, many scattered patches of coral-rock, some
of them raised to a height of forty feet."  These knolls of coral-rock were
evidently once separate reefs in the lagoon of an atoll.  Mr. Martens, at
Sydney, informed me that this island is surrounded by a terrace-like plain
at about the height of a hundred feet, which probably marks a pause in its
elevation.  From these facts we may infer, perhaps, that the Cook and
Austral Islands have been upheaved at a period probably not very remote.

SAVAGE Island (S.E. of the Friendly group), is about forty feet in height.
Forster ("Observations made during Voyage round the World," page 147.)
describes the plants as already growing out of the dead, but still upright
and spreading trees of coral; and the younger Forster ("Voyage," volume
ii., page 163.) believes that an ancient lagoon is now represented by a
central plain; here we cannot doubt that the elevatory forces have recently
acted.  The same conclusion may be extended, though with somewhat less
certainty, to the islands of the FRIENDLY GROUP, which have been well
described in the second and third voyages of Cook.  The surface of
Tongatabou is low and level, but with some parts a hundred feet high; the
whole consists of coral-rock, "which yet shows the cavities and
irregularities worn into it by the action of the tides."  (Cook's "Third
Voyage" (4to edition), volume i., page 314.)  On Eoua the same appearances
were noticed at an elevation of between two hundred and three hundred feet.
Vavao, also, at the opposite or northern end of the group, consists,
according to the Rev. J. Williams, of coral-rock.  Tongatabou, with its
northern extensive reefs, resembles either an upraised atoll with one half
originally imperfect, or one unequally elevated; and Anamouka, an atoll
equally elevated.  This latter island contains (Ibid., volume i., page
235.) in its centre a salt-water lake, about a mile-and-a-half in diameter,
without any communication with the sea, and around it the land rises
gradually like a bank; the highest part is only between twenty and thirty
feet; but on this part, as well as on the rest of the land (which, as Cook
observes, rises above the height of true lagoon-islands), coral-rock, like
that on the beach, was found.  In the NAVIGATOR ARCHIPELAGO, Mr. Couthouy
("Remarks on Coral-Formations," page 50.) found on Manua many and very
large fragments of coral at the height of eighty feet, "on a steep hill-side,
rising half a mile inland from a low sandy plain abounding in marine
remains."  The fragments were embedded in a mixture of decomposed lava and
sand.  It is not stated whether they were accompanied by shells, or whether
the corals resembled recent species; as these remains were embedded they
possibly may belong to a remote epoch; but I presume this was not the
opinion of Mr. Couthouy.  Earthquakes are very frequent in this
archipelago.

Still proceeding westward we come to the NEW HEBRIDES; on these islands,
Mr. G. Bennett (author of "Wanderings in New South Wales"), informs me he
found much coral at a great altitude, which he considered of recent origin.
Respecting SANTA CRUZ, and the SOLOMON ARCHIPELAGO, I have no information;
but at New Ireland, which forms the northern point of the latter chain,
both Labillardiere and Lesson have described large beds of an apparently
very modern madreporitic rock, with the form of the corals little altered.
The latter author ("Voyage de la 'Coquille'," Part. Zoolog.) states that
this formation composes a newer line of coast, modelled round an ancient
one.  There only remains to be described in the Pacific, that curved line
of fringed islands, of which the MARIANAS form the main part.  Of these
Guam, Rota, Tiniam, Saypan, and some islets farther north, are described by
Quoy and Gaimard (Freycinet's "Voyage autour du Monde."  See also the
"Hydrographical Memoir," page 215.), and Chamisso (Kotzebue's "First
Voyage."), as chiefly composed of madreporitic limestone, which attains a
considerable elevation, and is in several cases worn into successively
rising cliffs: the two former naturalists seem to have compared the corals
and shells with the existing ones, and state that they are of recent
species.  FAIS, which lies in the prolonged line of the Marianas, is the
only island in this part of the sea which is fringed; it is ninety feet
high, and consists entirely of madreporitic rock.  (Lutke's "Voyage,"
volume ii., page 304.)

In the EAST INDIAN ARCHIPELAGO, many authors have recorded proofs of recent
elevation.  M. Lesson (Partie Zoolog., "Voyage de la 'Coquille'.") states,
that near Port Dory, on the north coast of New Guinea, the shores are
flanked, to the height of 150 feet, by madreporitic strata of modern date.
He mentions similar formations at Waigiou, Amboina, Bourou, Ceram, Sonda,
and Timor: at this latter place, MM. Quoy and Gaimard ("Ann. des Scien.
Nat." tom. vi., page 281.) have likewise described the primitive rocks, as
coated to a considerable height with coral.  Some small islets eastward of
Timor are said in Kolff's "Voyage," (translated by Windsor Earl, chapters
vi., vii.) to resemble small coral islets upraised some feet above the sea.
Dr. Malcolmson informs me that Dr. Hardie found in JAVA an extensive
formation, containing an abundance of shells, of which the greater part
appear to be of existing species.  Dr. Jack ("Geolog. Transact." 2nd
series, volume i., page 403.  On the Peninsula of Malacca, in front of
Pinang, 5 deg 30' N., Dr. Ward collected some shells, which Dr. Malcolmson
informs me, although not compared with existing species, had a recent
appearance.  Dr. Ward describes in this neighbourhood ("Trans. Asiat. Soc."
volume xviii., part ii., page 166) a single water-worn rock, with a
conglomerate of sea-shells at its base, situated six miles inland, which,
according to the traditions of the natives, was once surrounded by the sea.
Captain Low has also described (Ibid., part i., page 131) mounds of shells
lying two miles inland on this line of coast.) has described some upraised
shells and corals, apparently recent, on Pulo Nias off SUMATRA; and Marsden
relates in his history of this great island, that the names of many
promontories, show that they were originally islands.  On part of the west
coast of BORNEO and at the SOOLOO Islands, the form of the land, the nature
of the soil, and the water-washed rocks, present appearances ("Notices of
the East Indian Arch." Singapore, 1828, page 6, and Append., page 43.)
(although it is doubtful whether such vague evidence is worthy of mention),
of having recently been covered by the sea; and the inhabitants of the
Sooloo Islands believe that this has been the case.  Mr. Cuming, who has
lately investigated, with so much success, the natural history of the
PHILIPPINES, found near Cabagan, in Luzon, about fifty feet above the level
of the R. Cagayan, and seventy miles from its mouth, a large bed of fossil
shells: these, he informs me, are of the same species with those now
existing on the shores of the neighbouring islands.  From the accounts
given us by Captain Basil Hall and Captain Beechey (Captain B. Hall,
"Voyage to Loo Choo," Append., pages xxi. and xxv.  Captain Beechey's
"Voyage," page 496.) of the lines of inland reefs, and walls of coral-rock
worn into caves, above the present reach of the waves, at the LOO CHOO
Islands, there can be little doubt that they have been upraised at no very
remote period.

Dr. Davy describes the northern province of CEYLON ("Travels in Ceylon,"
page 13.  This madreporitic formation is mentioned by M. Cordier in his
report to the Institute (May 4th, 1839), on the voyage of the "Chevrette",
as one of immense extent, and belonging to the latest tertiary period.) as
being very low, and consisting of a limestone with shells and corals of
very recent origin; he adds, that it does not admit of a doubt that the sea
has retired from this district even within the memory of man.  There is
also some reason for believing that the western shores of India, north of
Ceylon, have been upraised within the recent period.  (Dr. Benza, in his
"Journey through the N. Circars" (the "Madras Lit. and Scient. Journ."
volume v.) has described a formation with recent fresh-water and marine
shells, occurring at the distance of three or four miles from the present
shore.  Dr. Benza, in conversation with me, attributed their position to a
rise of the land.  Dr. Malcolmson, however (and there cannot be a higher
authority on the geology of India) informs me that he suspects that these
beds may have been formed by the mere action of the waves and currents
accumulating sediment.  From analogy I should much incline to Dr. Benza's
opinion.)  MAURITIUS has certainly been upraised within the recent period,
as I have stated in the chapter on fringing-reefs.  The northern extremity
of MADAGASCAR is described by Captain Owen (Owen's "Africa," volume ii.,
page 37, for Madagascar; and for S. Africa, volume i., pages 412 and 426.
Lieutenant Boteler's narrative contains fuller particulars regarding the
coral-rock, volume i., page 174, and volume ii., pages 41 and 54.  See also
Ruschenberger's "Voyage round the World," volume i., page 60.) as formed of
madreporitic rock, as likewise are the shores and outlying islands along an
immense space of EASTERN AFRICA, from a little north of the equator for
nine hundred miles southward.  Nothing can be more vague than the
expression "madreporitic rock;" but at the same time it is, I think,
scarcely possible to look at the chart of the linear islets, which rise to
a greater height than can be accounted for by the growth of coral, in front
of the coast, from the equator to 2 deg S., without feeling convinced that
a line of fringing-reefs has been elevated at a period so recent, that no
great changes have since taken place on the surface of this part of the
globe.  Some, also, of the higher islands of madreporitic rock on this
coast, for instance Pemba, have very singular forms, which seem to show the
combined effect of the growth of coral round submerged banks, and their
subsequent upheaval.  Dr. Allan informs me that he never observed any
elevated organic remains on the SEYCHELLES, which come under our fringed
class.

The nature of the formations round the shores of the RED SEA, as described
by several authors, shows that the whole of this large area has been
elevated within a very recent tertiary epoch.  A part of this space in the
appended map, is coloured blue, indicating the presence of barrier-reefs:
on which circumstance I shall presently make some remarks.  Ruppell
(Ruppell, "Reise in Abyssinien," Band i., s. 141.) states that the tertiary
formation, of which he has examined the organic remains, forms a fringe
along the shores with a uniform height of from thirty and forty feet from
the mouth of the Gulf of Suez to about latitude 26 deg; but that south of
26 deg, the beds attain only the height of from twelve to fifteen feet.
This, however, can hardly be quite accurate; although possibly there may be
a decrease in the elevation of the shores in the middle parts of the Red
Sea, for Dr. Malcolmson (as he informs me) collected from the cliffs of
Camaran Island (latitude 15 deg 30' S.) shells and corals, apparently
recent, at a height between thirty and forty feet; and Mr. Salt ("Travels
in Abyssinia") describes a similar formation a little southward on the
opposite shore at Amphila.  Moreover, near the mouth of the Gulf of Suez,
although on the coast opposite to that on which Dr. Ruppell says that the
modern beds attain a height of only thirty to forty feet, Mr. Burton
(Lyell's "Principles of Geology," 5th edition, volume iv., page 25.) found
a deposit replete with existing species of shells, at the height of 200
feet.  In an admirable series of drawings by Captain Moresby, I could see
how continuously the cliff-bounded low plains of this formation extended
with a nearly equable height, both on the eastern and western shores.  The
southern coast of Arabia seems to have been subjected to the same elevatory
movement, for Dr. Malcolmson found at Sahar low cliffs containing shells
and corals, apparently of recent species.

The PERSIAN GULF abounds with coral-reefs; but as it is difficult to
distinguish them from sand-banks in this shallow sea, I have coloured only
some near the mouth; towards the head of the gulf Mr. Ainsworth
(Ainsworth's "Assyria and Babylon," page 217.) says that the land is worn
into terraces, and that the beds contain organic remains of existing forms.
The WEST INDIAN ARCHIPELAGO of "fringed" islands, alone remains to be
mentioned; evidence of an elevation within a late tertiary epoch of nearly
the whole of this great area, may be found in the works of almost all the
naturalists who have visited it.  I will give some of the principal
references in a note.  (On Florida and the north shores of the Gulf of
Mexico, Rogers' "Report to Brit. Assoc." volume iii., page 14.--On the
shores of Mexico, Humboldt, "Polit. Essay on New Spain," volume i., page
62.  (I have also some corroborative facts with respect to the shores of
Mexico.)--Honduras and the Antilles, Lyell's "Principles," 5th edition,
volume iv., page 22.--Santa Cruz and Barbadoes, Prof. Hovey, "Silliman's
Journal", volume xxxv., page 74.--St. Domingo, Courrojolles, "Journ de
Phys." tom. liv., page 106.--Bahamas, "United Service Journal", No. lxxi.,
pages 218 and 224.  Jamaica, De la Beche, "Geol. Man." page 142.--Cuba,
Taylor in "Lond. and Edin. Mag." volume xi., page 17.  Dr. Daubeny also, at
a meeting of the Geolog. Soc., orally described some very modern beds lying
on the N.W. parts of Cuba.  I might have added many other less important
references.)

It is very remarkable on reviewing these details, to observe in how many
instances fringing-reefs round the shores, have coincided with the
existence on the land of upraised organic remains, which seem, from
evidence more or less satisfactory, to belong to a late tertiary period.
It may, however, be objected, that similar proofs of elevation, perhaps,
occur on the coasts coloured blue in our map: but this certainly is not
the case with the few following and doubtful exceptions.

The entire area of the Red Sea appears to have been upraised within a
modern period; nevertheless I have been compelled (though on unsatisfactory
evidence, as given in the Appendix) to class the reefs in the middle part,
as barrier-reefs; should, however, the statements prove accurate to the
less height of the tertiary bed in this middle part, compared with the
northern and southern districts, we might well suspect that it had subsided
subsequently to the general elevation by which the whole area has been
upraised.  Several authors (Ellis, in his "Polynesian Researches," was the
first to call attention to these remains (volume i., page 38), and the
tradition of the natives concerning them.  See also Williams, "Nar. of
Missionary Enterprise," page 21; also Tyerman and G. Bennett, "Journal of
Voyage," volume i., page 213; also Mr. Couthouy's "Remarks," page 51; but
this principal fact, namely, that there is a mass of upraised coral on the
narrow peninsula of Tiarubu, is from hearsay evidence; also Mr. Stutchbury,
"West of England Journal," No. i., page 54.  There is a passage in Von
Zach, "Corres. Astronom." volume x., page 266, inferring an uprising at
Tahiti, from a footpath now used, which was formerly impassable; but I
particularly inquired from several native chiefs, whether they knew of any
change of this kind, and they were unanimous in giving me an answer in the
negative.) have stated that they have observed shells and corals high up on
the mountains of the Society Islands,--a group encircled by barrier-reefs,
and, therefore, supposed to have subsided: at Tahiti Mr. Stutchbury found
on the apex of one of the highest mountains, between 5,000 and 7,000 feet
above the level of the sea, "a distinct and regular stratum of semi-fossil
coral."  At Tahiti, however, other naturalists, as well as myself, have
searched in vain at a low level near the coast, for upraised shells or
masses of coral-reef, where if present they could hardly have been
overlooked.  From this fact, I concluded that probably the organic remains
strewed high up on the surface of the land, had originally been embedded in
the volcanic strata, and had subsequently been washed out by the rain.  I
have since heard from the Rev. W. Ellis, that the remains which he met
with, were (as he believes) interstratified with an argillaceous tuff; this
likewise was the case with the shells observed by the Rev. D. Tyerman at
Huaheine.  These remains have not been specifically examined; they may,
therefore, and especially the stratum observed by Mr. Stutchbury at an
immense height, be contemporaneous with the first formation of the Society
Islands, and be of any degree of antiquity; or they may have been deposited
at some subsequent, but probably not very recent, period of elevation; for
if the period had been recent, the entire surface of the coast land of
these islands, where the reefs are so extensive, would have been coated
with upraised coral, which certainly is not the case.  Two of the Harvey,
or Cook Islands, namely, Aitutaki and Manouai, are encircled by reefs,
which extend so far from the land, that I have coloured them blue, although
with much hesitation, as the space within the reef is shallow, and the
outline of the land is not abrupt.  These two islands consist of coral-rock;
but I have no evidence of their recent elevation, besides, the
improbability of Mangaia, a fringed island in the same group (but distant
170 miles), having retained its nearly perfect atoll-like structure, during
any immense lapse of time after its upheaval.  The Red Sea, therefore, is
the only area in which we have clear proofs of the recent elevation of a
district, which, by our theory (although the barrier-reefs are there not
well characterised), has lately subsided.  But we have no reason to be
surprised at oscillation, of level of this kind having occasionally taken
place.  There can be scarcely any doubt that Savage, Aurora (Aurora Island
is described by Mr. Couthouy ("Remarks," page 58); it lies 120 miles
north-east of Tahiti; it is not coloured in the appended map, because it does
not appear to be fringed by living reefs.  Mr. Couthouy describes its summit
as "presenting a broad table-land which declines a few feet towards the
centre, where we may suppose the lagoon to have been placed."  It is about
two hundred feet in height, and consists of reef-rock and conglomerate,
with existing species of coral embedded in it.  The island has been
elevated at two successive periods; the cliffs being marked halfway up with
a horizontal water-worn line of deep excavations.  Aurora Island seems
closely to resemble in structure Elizabeth Island, at the southern end of
the Low Archipelago.), and Mangaia Islands, and several of the islands in
the Friendly group, existed originally as atolls, and these have
undoubtedly since been upraised to some height above the level of the sea;
so that by our theory, there has here, also, been an oscillation of level,
--elevation having succeeded subsidence, instead of, as in the middle part
of the Red Sea and at the Harvey Islands, subsidence having probably
succeeded recent elevation.

It is an interesting fact, that Fais, which, from its composition, form,
height, and situation at the western end of the Caroline Archipelago, one
is strongly induced to believe existed before its upheaval as an atoll,
lies exactly in the prolongation of the curved line of the Mariana group,
which we know to be a line of recent elevation.  I may add, that Elizabeth
Island, in the southern part of the Low Archipelago, which seems to have
had the same kind of origin as Fais, lies near Pitcairn Island, the only
one in this part of the ocean which is high, and at the same time not
surrounded by an encircling barrier-reef.

ON THE ABSENCE OF ACTIVE VOLCANOES IN THE AREAS OF SUBSIDENCE, AND ON THEIR
FREQUENT PRESENCE IN THE AREAS OF ELEVATION.

Before making some concluding remarks on the relations of the spaces
coloured blue and red, it will be convenient to consider the position on
our map of the volcanoes historically known to have been in action.  It is
impossible not to be struck, first with the absence of volcanoes in the
great areas of subsidence tinted pale and dark blue,--namely, in the
central parts of the Indian Ocean, in the China Sea, in the sea between the
barriers of Australia and New Caledonia, in the Caroline, Marshall,
Gilbert, and Low Archipelagoes; and, secondly, with the coincidence of the
principal volcanic chains with the parts coloured red, which indicates the
presence of fringing-reefs; and, as we have just seen, the presence in most
cases of upraised organic remains of a modern date.  I may here remark that
the reefs were all coloured before the volcanoes were added to the map, or
indeed before I knew of the existence of several of them.

The volcano in Torres Strait, at the northern point of Australia, is that
which lies nearest to a large subsiding area, although situated 125 miles
within the outer margin of the actual barrier-reef.  The Great Comoro
Island, which probably contains a volcano, is only twenty miles distant
from the barrier-reef of Mohila; Ambil volcano, in the Philippines, is
distant only a little more than sixty miles from the atoll-formed Appoo
reef: and there are two other volcanoes in the map within ninety miles of
circles coloured blue.  These few cases, which thus offer partial
exceptions to the rule, of volcanoes being placed remote from the areas of
subsidence, lie either near single and isolated atolls, or near small
groups of encircled islands; and these by our theory can have, in few
instances, subsided to the same amount in depth or area, as groups of
atolls.  There is not one active volcano within several hundred miles of an
archipelago, or even a small group of atolls.  It is, therefore, a striking
fact that in the Friendly Archipelago, which owes its origin to the
elevation of a group of atolls, two volcanoes, and, perhaps, others are
known to be in action: on the other hand, on several of the encircled
islands in the Pacific, supposed by our theory to have subsided, there are
old craters and streams of lava, which show the effects of past and ancient
eruptions.  In these cases, it would appear as if the volcanoes had come
into action, and had become extinguished on the same spots, according as
the elevating or subsiding movements prevailed.

There are some other coasts on the map, where volcanoes in a state of
action concur with proofs of recent elevation, besides those coloured red
from being fringed by coral-reefs.  Thus I hope to show in a future volume,
that nearly the whole line of the west coast of South America, which forms
the greatest volcanic chain in the world, from near the equator for a space
of between 2,000 and 3,000 miles southward, has undergone an upward
movement during a late geological period.  The islands on the north-western
shores of the Pacific, which form the second greatest volcanic chain, are
very imperfectly known; but Luzon, in the Philippines, and the Loo Choo
Islands, have been recently elevated; and at Kamtschatka (At Sedanka, in
latitude 58 deg N. (Von Buch's "Descrip. des Isles Canaries," page 455).
In a forthcoming part, I shall give the evidence referred to with respect
to the elevation of New Zealand.) there are extensive tertiary beds of
modern date.  Evidence of the same nature, but not very satisfactory, may
be detected in Northern New Zealand where there are two volcanoes.  The
co-existence in other parts of the world of active volcanoes, with upraised
beds of a modern tertiary origin, will occur to every geologist.  (During
the subterranean disturbances which took place in Chile, in 1835, I have
shown ("Geolog. Trans." 2nd Ser., vol. v., page 606) that at the same
moment that a large district was upraised, volcanic matter burst forth at
widely separated points, through both new and old vents.)  Nevertheless,
until it could be shown that volcanoes were inactive, or did not exist in
subsiding areas, the conclusion that their distribution depended on the
nature of the subterranean movements in progress, would have been
hazardous.  But now, viewing the appended map, it may, I think, be
considered as almost established, that volcanoes are often (not necessarily
always) present in those areas where the subterranean motive power has
lately forced, or is now forcing outwards, the crust of the earth, but that
they are invariably absent in those, where the surface has lately subsided
or is still subsiding.  (We may infer from this rule, that in any old
deposit, which contains interstratified beds of erupted matter, there was
at the period, and in the area of its formation, a TENDENCY to an upward
movement in the earth's surface, and certainly no movement of subsidence.)

ON THE RELATIONS OF THE AREAS OF SUBSIDENCE AND ELEVATION.

The immense surfaces on the map, which, both by our theory and by the plain
evidence of upraised marine remains, have undergone a change of level
either downwards or upwards during a late period, is a most remarkable
fact.  The existence of continents shows that the areas have been immense
which at some period have been upraised; in South America we may feel sure,
and on the north-western shores of the Indian Ocean we may suspect, that
this rising is either now actually in progress, or has taken place quite
recently.  By our theory, we may conclude that the areas are likewise
immense which have lately subsided, or, judging from the earthquakes
occasionally felt and from other appearances, are now subsiding.  The
smallness of the scale of our map should not be overlooked: each of the
squares on it contains (not allowing for the curvature of the earth)
810,000 square miles.  Look at the space of ocean from near the southern
end of the Low Archipelago to the northern end of the Marshall Archipelago,
a length of 4,500 miles, in which, as far as is known, every island, except
Aurora which lies just without the Low Archipelago, is atoll-formed.  The
eastern and western boundaries of our map are continents, and they are
rising areas: the central spaces of the great Indian and Pacific Oceans,
are mostly subsiding; between them, north of Australia, lies the most
broken land on the globe, and there the rising parts are surrounded and
penetrated by areas of subsidence (I suspect that the Arru and Timor-laut
Islands present an included small area of subsidence, like that of the
China Sea, but I have not ventured to colour them from my imperfect
information, as given in the Appendix.), so that the prevailing movements
now in progress, seem to accord with the actual states of surface of the
great divisions of the world.

The blue spaces on the map are nearly all elongated; but it does not
necessarily follow from this (a caution, for which I am indebted to Mr.
Lyell), that the areas of subsidence were likewise elongated; for the
subsidence of a long, narrow space of the bed of the ocean, including in it
a transverse chain of mountains, surmounted by atolls, would only be marked
on the map by a transverse blue band.  But where a chain of atolls and
barrier-reefs lies in an elongated area, between spaces coloured red, which
therefore have remained stationary or have been upraised, this must have
resulted either from the area of subsidence having originally been
elongated (owing to some tendency in the earth's crust thus to subside), or
from the subsiding area having originally been of an irregular figure, or
as broad as long, and having since been narrowed by the elevation of
neighbouring districts.  Thus the areas, which subsided during the
formation of the great north and south lines of atolls in the Indian
Ocean,--of the east and west line of the Caroline atolls,--and of the
north-west and south-east line of the barrier-reefs of New Caledonia and
Louisiade, must have originally been elongated, or if not so, they must
have since been made elongated by elevations, which we know to belong to a
recent period.

I infer from Mr. Hopkins' researches ("Researches in Physical Geology,"
Transact. Cambridge Phil. Soc., volume vi, part i.), that for the formation
of a long chain of mountains, with few lateral spurs, an area elongated in
the same direction with the chain, must have been subjected to an elevatory
movement.  Mountain-chains, however, when already formed, although running
in very different directions, it seems (For instance in S. America from
latitude 34 deg, for very many degrees southward there are upraised beds
containing recent species of shells, on both the Atlantic and Pacific side
of the continent, and from the gradual ascent of the land, although with
very unequal slopes, on both sides towards the Cordillera, I think it can
hardly be doubted that the entire width has been upraised in mass within
the recent period.  In this case the two W.N.W. and E.S.E. mountain-lines,
namely the Sierra Ventana and the S. Tapalguen, and the great north and
south line of the Cordillera have been together raised.  In the West Indies
the N. and S. line of the Eastern Antilles, and the E. and W. line of
Jamaica, appear both to have been upraised within the latest geological
period.) may be raised together by a widely-acting force: so, perhaps,
mountain-chains may subside together.  Hence, we cannot tell, whether the
Caroline and Marshall Archipelagoes, two groups of atolls running in
different directions and meeting each other, have been formed by the
subsidence of two areas, or of one large area, including two distinct lines
of mountains.  We have, however, in the southern prolongation of the
Mariana Islands, probable evidence of a line of recent elevation having
intersected one of recent subsidence.  A view of the map will show that,
generally, there is a tendency to alternation in the parallel areas
undergoing opposite kinds of movement; as if the sinking of one area
balanced the rising of another.

The existence in many parts of the world of high table-land, proves that
large surfaces have been upraised in mass to considerable heights above the
level of the ocean; although the highest points in almost every country
consist of upturned strata, or erupted matter: and from the immense spaces
scattered with atolls, which indicate that land originally existed there,
although not one pinnacle now remains above the level of the sea, we may
conclude that wide areas have subsided to an amount, sufficient to bury not
only any formerly existing table-land, but even the heights formed by
fractured strata, and erupted matter.  The effects produced on the land by
the later elevatory movements, namely, successively rising cliffs, lines of
erosion, and beds of literal shells and pebbles, all requiring time for
their production, prove that these movements have been very slow; we can,
however, infer this with safety, only with respect to the few last hundred
feet of rise.  But with reference to the whole vast amount of subsidence,
necessary to have produced the many atolls widely scattered over immense
spaces, it has already been shown (and it is, perhaps, the most interesting
conclusion in this volume), that the movements must either have been
uniform and exceedingly slow, or have been effected by small steps,
separated from each other by long intervals of time, during which the
reef-constructing polypifers were able to bring up their solid frameworks
to the surface.  We have little means of judging whether many considerable
oscillations of level have generally occurred during the elevation of large
tracts; but we know, from clear geological evidence, that this has
frequently taken place; and we have seen on our map, that some of the same
islands have both subsided and been upraised.  I conclude, however, that
most of the large blue spaces, have subsided without many and great
elevatory oscillations, because only a few upraised atolls have been
observed: the supposition that such elevations have taken place, but that
the upraised parts have been worn down by the surf, and thus have escaped
observation, is overruled by the very considerable depth of the lagoons of
all the larger atolls; for this could not have been the case, if they had
suffered repeated elevations and abrasion.  From the comparative
observations made in these latter pages, we may finally conclude, that the
subterranean changes which have caused some large areas to rise, and others
to subside, have acted in a very similar manner.

RECAPITULATION.

In the three first chapters, the principal kinds of coral-reefs were
described in detail, and they were found to differ little, as far as
relates to the actual surface of the reef.  An atoll differs from an
encircling barrier-reef only in the absence of land within its central
expanse; and a barrier-reef differs from a fringing-reef, in being placed
at a much greater distance from the land with reference to the probable
inclination of its submarine foundation, and in the presence of a deep-water
lagoon-like space or moat within the reef.  In the fourth chapter the
growing powers of the reef-constructing polypifers were discussed; and it
was shown, that they cannot flourish beneath a very limited depth.  In
accordance with this limit, there is no difficulty respecting the
foundations on which fringing-reefs are based; whereas, with barrier-reefs
and atolls, there is a great apparent difficulty on this head; in
barrier-reefs from the improbability of the rock of the coast or of banks of
sediment extending, in every instance, so far seaward within the required
depth;--and in atolls, from the immensity of the spaces over which they are
interspersed, and the apparent necessity for believing that they are all
supported on mountain-summits, which although rising very near to the
surface-level of the sea, in no one instance emerge above it.  To escape
this latter most improbable admission, which implies the existence of
submarine chains of mountains of almost the same height, extending over
areas of many thousand square miles, there is but one alternative; namely,
the prolonged subsidence of the foundations, on which the atolls were
primarily based, together with the upward growth of the reef-constructing
corals.  On this view every difficulty vanishes; fringing reefs are thus
converted into barrier-reefs; and barrier-reefs, when encircling islands,
are thus converted into atolls, the instant the last pinnacle of land sinks
beneath the surface of the ocean.

Thus the ordinary forms and certain peculiarities in the structure of
atolls and barrier-reefs can be explained;--namely, the wall-like structure
on their inner sides, the basin or ring-like shape both of the marginal and
central reefs in the Maldiva atolls--the union of some atolls as if by a
ribbon--the apparent disseverment of others--and the occurrence, in atolls
as well as in barrier-reefs, of portions of reef, and of the whole of some
reefs, in a dead and submerged state, but retaining the outline of living
reefs.  Thus can be explained the existence of breaches through barrier-reefs
in front of valleys, though separated from them by a wide space of
deep water; thus, also, the ordinary outline of groups of atolls and the
relative forms of the separate atolls one to another; thus can be explained
the proximity of the two kinds of reefs formed during subsidence, and their
separation from the spaces where fringing-reefs abound.  On searching for
other evidence of the movements supposed by our theory, we find marks of
change in atolls and in barrier-reefs, and of subterranean disturbances
under them; but from the nature of things, it is scarcely possible to
detect any direct proofs of subsidence, although some appearances are
strongly in favour of it.  On the fringed coasts, however, the presence of
upraised marine bodies of a recent epoch, plainly show, that these coasts,
instead of having remained stationary, which is all that can be directly
inferred from our theory, have generally been elevated.

Finally, when the two great types of structure, namely barrier-reefs and
atolls on the one hand, and fringing-reefs on the other, were laid down in
colours on our map, a magnificent and harmonious picture of the movements,
which the crust of the earth has within a late period undergone, is
presented to us.  We there see vast areas rising, with volcanic matter
every now and then bursting forth through the vents or fissures with which
they are traversed.  We see other wide spaces slowly sinking without any
volcanic outburst, and we may feel sure, that this sinking must have been
immense in amount as well as in area, thus to have buried over the broad
face of the ocean every one of those mountains, above which atolls now
stand like monuments, marking the place of their former existence.
Reflecting how powerful an agent with respect to denudation, and
consequently to the nature and thickness of the deposits in accumulation,
the sea must ever be, when acting for prolonged periods on the land, during
either its slow emergence or subsidence; reflecting, also, on the final
effects of these movements in the interchange of land and ocean-water on
the climate of the earth, and on the distribution of organic beings, I may
be permitted to hope, that the conclusions derived from the study of
coral-formations, originally attempted merely to explain their peculiar
forms, may be thought worthy of the attention of geologists.


APPENDIX.

CONTAINING A DETAILED DESCRIPTION OF THE REEFS AND ISLANDS IN PLATE III.

In the beginning of the last chapter I stated the principles on which the
map is coloured.  There only remains to be said, that it is an exact copy
of one by M. C. Gressier, published by the Depot General de la Marine, in
1835.  The names have been altered into English, and the longitude has been
reduced to that of Greenwich.  The colours were first laid down on accurate
charts, on a large scale.  The data, on which the volcanoes historically
known to have been in action, have been marked with vermillion, were given
in a note to the last chapter.  I will commence my description on the
eastern side of the map, and will describe each group of islands
consecutively, proceeding westward across the Pacific and Indian Oceans,
but ending with the West Indies.

The WESTERN SHORES OF AMERICA appear to be entirely without coral-reefs;
south of the equator the survey of the "Beagle", and north of it, the
published charts show that this is the case.  Even in the Bay of PANAMA,
where corals flourish, there are no true coral-reefs, as I have been
informed by Mr. Lloyd.  There are no coral-reefs in the GALAPAGOS
Archipelago, as I know from personal inspection; and I believe there are
none on the COCOS, REVILLA-GIGEDO, and other neighbouring islands.
CLIPPERTON rock, 10 deg N., 109 deg W., has lately been surveyed by Captain
Belcher; in form it is like the crater of a volcano.  From a drawing
appended to the MS. plan in the Admiralty, it evidently is not an atoll.
The eastern parts of the Pacific present an enormous area, without any
islands, except EASTER, and SALA, and GOMEZ Islands, which do not appear to
be surrounded by reefs.

THE LOW ARCHIPELAGO.

This group consists of about eighty atolls: it will be quite superfluous
to refer to descriptions of each.  In D'Urville and Lottin's chart, one
island (WOLCHONSKY) is written with a capital letter, signifying, as
explained in a former chapter, that it is a high island; but this must be a
mistake, as the original chart by Bellinghausen shows that it is a true
atoll.  Captain Beechey says of the thirty-two groups which he examined (of
the greater number of which I have seen beautiful MS. charts in the
Admiralty), that twenty-nine now contain lagoons, and he believes the other
three originally did.  Bellinghausen (see an account of his Russian voyage,
in the "Biblioth. des Voyages," 1834, page 443) says, that the seventeen
islands which he discovered resembled each other in structure, and he has
given charts on a large scale of all of them.  Kotzebue has given plans of
several; Cook and Bligh mention others; a few were seen during the voyage
of the "Beagle"; and notices of other atolls are scattered through several
publications.  The ACTAEON group in this archipelago has lately been
discovered ("Geographical Journal", volume vii., page 454); it consists of
three small and low islets, one of which has a lagoon.  Another lagoon-island
has been discovered ("Naut. Mag." 1839, page 770), in 22 deg 4' S.,
and 136 deg 20' W.  Towards the S.E. part of the group, there are some
islands of different formation: ELIZABETH Island is described by Beechey
(page 46, 4to edition) as fringed by reefs, at the distance of between two
and three hundred yards; coloured red.  PITCAIRN Island, in the immediate
neighbourhood, according to the same authority, has no reefs of any kind,
although numerous pieces of coral are thrown up on the beach; the sea close
to its shore is very deep (see "Zool. of Beechey's Voyage," page 164); it
is left uncoloured.  GAMBIER Islands (see Plate I., Figure 8), are
encircled by a barrier-reef; the greatest depth within is thirty-eight
fathoms; coloured pale blue.  AURORA Island, which lies N.E. of Tahiti
close to the large space coloured dark blue in the map, has been already
described in a note (page 71), on the authority of Mr. Couthouy; it is an
upraised atoll, but as it does not appear to be fringed by living reefs, it
is left uncoloured.

The SOCIETY Archipelago is separated by a narrow space from the Low
Archipelago; and in their parallel direction they manifest some relation to
each other.  I have already described the general character of the reefs of
these fine encircled islands.  In the "Atlas of the 'Coquille's' Voyage"
there is a good general chart of the group, and separate plans of some of
the islands.  TAHITI, the largest island in the group, is almost
surrounded, as seen in Cook's chart, by a reef from half a mile to a mile
and a half from the shore, with from ten to thirty fathoms within it.  Some
considerable submerged reefs lying parallel to the shore, with a broad and
deep space within, have lately been discovered ("Naut. Mag." 1836, page
264) on the N.E. coast of the island, where none are laid down by Cook.  At
EIMEO the reef "which like a ring surrounds it, is in some places one or
two miles distant from the shore, in others united to the beach" (Ellis,
"Polynesian Researches," volume i., page 18, 12mo edition).  Cook found
deep water (twenty fathoms) in some of the harbours within the reef.  Mr.
Couthouy, however, states ("Remarks," page 45) that both at Tahiti and
Eimeo, the space between the barrier-reef and the shore, has been almost
filled up,--"a nearly continuous fringing-reef surrounding the island, and
varying from a few yards to rather more than a mile in width, the lagoons
merely forming canals between this and the sea-reef," that is the
barrier-reef.  TAPAMANOA is surrounded by a reef at a considerable distance
from the shore; from the island being small it is breached, as I am informed
by the Rev. W. Ellis, only by a narrow and crooked boat channel.  This is the
lowest island in the group, its height probably not exceeding 500 feet.  A
little way north of Tahiti, the low coral-islets of TETUROA are situated;
from the description of them given me by the Rev. J. Williams (the author
of the "Narrative of Missionary Enterprise"), I should have thought they
had formed a small atoll, and likewise from the description given by the
Rev. D. Tyerman and G. Bennett ("Journal of Voyage and Travels," volume i.,
page 183), who say that ten low coral-islets "are comprehended within one
general reef, and separated from each other by interjacent lagoons;" but as
Mr. Stutchbury ("West of England Journal," volume i., page 54) describes it
as consisting of a mere narrow ridge, I have left it uncoloured.  MAITEA,
eastward of the group, is classed by Forster as a high encircled island;
but from the account given by the Rev. D. Tyerman and G. Bennett (volume
i., page 57) it appears to be an exceedingly abrupt cone, rising from the
sea without any reef; I have left it uncoloured.  It would be superfluous
to describe the northern islands in this group, as they may be well seen in
the chart accompanying the 4to edition of Cook's "Voyages," and in the
"Atlas of the 'Coquille's' Voyage."  MAURUA is the only one of the northern
islands, in which the water within the reef is not deep, being only four
and a half fathoms; but the great width of the reef, stretching three miles
and a half southward of the land (which is represented in the drawing in
the "Atlas of the 'Coquille's' Voyage" as descending abruptly to the water)
shows, on the principle explained in the beginning of the last chapter,
that it belongs to the barrier class.  I may here mention, from information
communicated to me by the Rev. W. Ellis, that on the N.E. side of HUAHEINE
there is a bank of sand, about a quarter of a mile wide, extending parallel
to the shore, and separated from it by an extensive and deep lagoon; this
bank of sand rests on coral-rock, and undoubtedly was originally a living
reef.  North of Bolabola lies the atoll of TOUBAI (Motou-iti of the
"'Coquille's' Atlas") which is coloured dark blue; the other islands,
surrounded by barrier-reefs, are pale blue; three of them are represented
in Figures 3, 4, and 5, in Plate I.  There are three low coral-groups lying
a little E. of the Society Archipelago, and almost forming part of it,
namely BELLINGHAUSEN, which is said by Kotzebue ("Second Voyage," volume
ii., page 255), to be a lagoon-island; MOPEHA, which, from Cook's
description ("Second Voyage," book iii., chapter i.), no doubt is an atoll;
and the SCILLY Islands, which are said by Wallis ("Voyage," chapter ix.) to
form a GROUP of LOW islets and shoals, and, therefore, probably, they
compose an atoll: the two former have been coloured blue, but not the
latter.

MENDANA OR MARQUESAS GROUP.

These islands are entirely without reefs, as may be seen in Krusenstern's
Atlas, making a remarkable contrast with the adjacent group of the Society
Islands.  Mr. F.D. Bennett has given some account of this group, in the
seventh volume of the "Geographical Journal".  He informs me that all the
islands have the same general character, and that the water is very deep
close to their shores.  He visited three of them, namely, DOMINICANA,
CHRISTIANA, and ROAPOA; their beaches are strewed with rounded masses of
coral, and although no regular reefs exist, yet the shore is in many places
lined by coral-rock, so that a boat grounds on this formation.  Hence these
islands ought probably to come within the class of fringed islands and be
coloured red; but as I am determined to err on the cautious side, I have
left them uncoloured.

COOK OR HARVEY AND AUSTRAL ISLAND.

PALMERSTON Island is minutely described as an atoll by Captain Cook during
his voyage in 1774; coloured blue.  AITUTAKI was partially surveyed by the
"Beagle" (see map accompanying "Voyages of 'Adventure' and 'Beagle'"); the
land is hilly, sloping gently to the beach; the highest point is 360 feet;
on the southern side the reef projects five miles from the land: off this
point the "Beagle" found no bottom with 270 fathoms: the reef is
surmounted by many low coral-islets.  Although within the reef the water is
exceedingly shallow, not being more than a few feet deep, as I am informed
by the Rev. J. Williams, nevertheless, from the great extension of this
reef into a profoundly deep ocean, this island probably belongs, on the
principle lately adverted to, to the barrier class, and I have coloured it
pale blue; although with much hesitation.--MANOUAI or HARVEY Island.  The
highest point is about fifty feet: the Rev. J. Williams informs me that
the reef here, although it lies far from the shore, is less distant than at
Aitutaki, but the water within the reef is rather deeper: I have also
coloured this pale blue with many doubts.--Round MITIARO Island, as I am
informed by Mr. Williams, the reef is attached to the shore; coloured red.
--MAUKI or Maouti; the reef round this island (under the name of Parry
Island, in the "Voyage of H.M.S. 'Blonde'," page 209) is described as a
coral-flat, only fifty yards wide, and two feet under water.  This
statement has been corroborated by Mr. Williams, who calls the reef
attached; coloured red.--AITU, or Wateeo; a moderately elevated hilly
island, like the others of this group.  The reef is described in Cook's
"Voyage," as attached to the shore, and about one hundred yards wide;
coloured red.--FENOUA-ITI; Cook describes this island as very low, not more
than six or seven feet high (volume i., book ii., chapter iii, 1777); in
the chart published in the "'Coquille's' Atlas," a reef is engraved close
to the shore: this island is not mentioned in the list given by Mr.
Williams (page 16) in the "Narrative of Missionary Enterprise;" nature
doubtful.  As it is so near Atiu, it has been unavoidably coloured red.--
RAROTONGA; Mr. Williams informs me that it is a lofty basaltic island with
an attached reef; coloured red.--There are three islands, ROUROUTI,
ROXBURGH, and HULL, of which I have not been able to obtain any account,
and have left them uncoloured.  Hull Island, in the French chart, is
written with small letters as being low.--MANGAIA; height about three
hundred feet; "the surrounding reef joins the shore" (Williams,
"Narrative," page 18); coloured red.--RIMETARA; Mr. Williams informs me
that the reef is rather close to the shore; but, from information given me
by Mr. Ellis, the reef does not appear to be quite so closely attached to
it as in the foregoing cases: the island is about three hundred feet high
("Naut. Mag." 1839, page 738); coloured red.--RURUTU; Mr. Williams and Mr.
Ellis inform me that this island has an attached reef; coloured red.  It is
described by Cook under the name of Oheteroa: he says it is not
surrounded, like the neighbouring islands by a reef; he must have meant a
distant reef.--TOUBOUAI; in Cook's chart ("Second Voyage," volume ii., page
2) the reef is laid down in part one mile, and in part two miles from the
shore.  Mr. Ellis ("Polynes. Res." volume iii., page 381) says the low land
round the base of the island is very extensive; and this gentleman informs
me that the water within the reef appears deep; coloured blue.--RAIVAIVAI,
or Vivitao; Mr. Williams informs me that the reef is here distant: Mr.
Ellis, however, says that this is certainly not the case on one side of the
island; and he believes that the water within the reef is not deep; hence I
have left it uncoloured.--LANCASTER Reef, described in "Naut. Mag." 1833
(page 693), as an extensive crescent-formed coral-reef.  I have not
coloured it.--RAPA, or Oparree; from the accounts given of it by Ellis and
Vancouver, there does not appear to be any reef.--I. DE BASS is an
adjoining island, of which I cannot find any account.--KEMIN Island;
Krusenstern seems hardly to know its position, and gives no further
particulars.

ISLANDS BETWEEN THE LOW AND GILBERT ARCHIPELAGOES.

CAROLINE Island (10 deg S., 150 deg W.) is described by Mr. F.D. Bennett
("Geographical Journal", volume vii., page 225) as containing a fine
lagoon; coloured blue.--FLINT Island (11 deg S., 151 deg W.); Krusenstern
believes that it is the same with Peregrino, which is described by Quiros
(Burney's "Chron. Hist." volume ii., page 283) as "a cluster of small
islands connected by a reef, and forming a lagoon in the middle;" coloured
blue.--WOSTOCK is an island a little more than half a mile in diameter, and
apparently quite flat and low, and was discovered by Bellinghausen; it is
situated a little west of Caroline Island, but it is not placed on the
French charts; I have not coloured it, although I entertain little doubt
from the chart of Bellinghausen, that it originally contained a small
lagoon.--PENRHYN Island (9 deg S., 158 deg W.); a plan of it in the "Atlas
of the First Voyage" of Kotzebue, shows that it is an atoll; blue.--
SLARBUCK Island (5 deg S., 156 deg W.) is described in Byron's "Voyage in
the 'Blonde'" (page 206) as formed of a flat coral-rock, with no trees; the
height not given; not coloured.--MALDEN Island (4 deg S., 154 deg W.); in
the same voyage (page 205) this island is said to be of coral formation,
and no part above forty feet high; I have not ventured to colour it,
although, from being of coral-formation, it is probably fringed; in which
case it should be red.--JARVIS, or BUNKER Island (0 deg 20' S., 160 deg W.)
is described by Mr. F.D. Bennett ("Geographical Journal", volume vii., page
227) as a narrow, low strip of coral-formation; not coloured.--BROOK, is a
small low island between the two latter; the position, and perhaps even the
existence of it is doubtful; not coloured.--PESCADO and HUMPHREY Islands; I
can find out nothing about these islands, except that the latter appears to
be small and low; not coloured.--REARSON, or Grand Duke Alexander's (10 S.,
161 deg W.); an atoll, of which a plan is given by Bellinghausen; blue.--
SOUVOROFF Islands (13 deg S., 163 deg W.); Admiral Krusenstern, in the most
obliging manner, obtained for me an account of these islands from Admiral
Lazareff, who discovered them.  They consist of five very low islands of
coral-formation, two of which are connected by a reef, with deep water
close to it.  They do not surround a lagoon, but are so placed that a line
drawn through them includes an oval space, part of which is shallow; these
islets, therefore, probably once (as is the case with some of the islands
in the Caroline Archipelago) formed a single atoll; but I have not coloured
them.--DANGER Island (10 deg S., 166 deg W.); described as low by Commodore
Byron, and more lately surveyed by Bellinghausen; it is a small atoll with
three islets on it; blue.--CLARENCE Island (9 deg S., 172 deg W.);
discovered in the "Pandora" (G. Hamilton's "Voyage," page 75): it is said,
"in running along the land, we saw several canoes crossing the LAGOONS;" as
this island is in the close vicinity of other low islands, and as it is
said, that the natives make reservoirs of water in old cocoa-nut trees
(which shows the nature of the land), I have no doubt it is an atoll, and
have coloured it blue.  YORK Island (8 deg S., 172 deg W.) is described by
Commodore Byron (chapter x. of his "Voyage") as an atoll; blue.--SYDNEY
Island (4 deg S., 172 deg W.) is about three miles in diameter, with its
interior occupied by a lagoon (Captain Tromelin, "Annal. Marit." 1829, page
297); blue.--PHOENIX Island (4 deg S., 171 deg W.) is nearly circular, low,
sandy, not more than two miles in diameter, and very steep outside
(Tromelin, "Annal. Marit." 1829, page 297); it may be inferred that this
island originally contained a lagoon, but I have not coloured it.--NEW
NANTUCKET (0 deg 15' N., 174 deg W.).  From the French chart it must be a
low island; I can find nothing more about it or about MARY Island; both
uncoloured.--GARDNER Island (5 deg S., 174 deg W.) from its position is
certainly the same as KEMIN Island described (Krusenstern, page 435, Appen.
to Mem., published 1827) as having a lagoon in its centre; blue.

ISLANDS SOUTH OF THE SANDWICH ARCHIPELAGO.

CHRISTMAS Island (2 deg N., 157 deg W.).  Captain Cook, in his "Third
Voyage" (Volume ii., chapter x.), has given a detailed account of this
atoll.  The breadth of the islets on the reef is unusually great, and the
sea near it does not deepen so suddenly as is generally the case.  It has
more lately been visited by Mr. F.D. Bennett ("Geographical Journal,"
volume vii., page 226); and he assures me that it is low and of
coral-formation: I particularly mention this, because it is engraved with a
capital letter, signifying a high island, in D'Urville and Lottin's chart.
Mr. Couthouy, also, has given some account of it ("Remarks," page 46) from
the Hawaiian "Spectator"; he believes it has lately undergone a small
elevation, but his evidence does not appear to me satisfactory; the deepest
part of the lagoon is said to be only ten feet; nevertheless, I have
coloured it blue.--FANNING Island (4 deg N., 158 deg W.) according to
Captain Tromelin ("Ann. Maritim." 1829, page 283), is an atoll: his
account as observed by Krusenstern, differs from that given in Fanning's
"Voyage" (page 224), which, however, is far from clear; coloured blue.--
WASHINGTON Island (4 deg N., 159 deg W.) is engraved as a low island in
D'Urville's chart, but is described by Fanning (page 226) as having a much
greater elevation than Fanning Island, and hence I presume it is not an
atoll; not coloured.--PALMYRA Island (6 deg N., 162 deg W.) is an atoll
divided into two parts (Krusenstern's "Mem. Suppl." page 50, also Fanning's
"Voyage," page 233); blue.--SMYTH'S or Johnston's Islands (17 deg N., 170
deg W.).  Captain Smyth, R.N., has had the kindness to inform me that they
consist of two very low, small islands, with a dangerous reef off the east
end of them.  Captain Smyth does not recollect whether these islets,
together with the reef, surrounded a lagoon; uncoloured.

SANDWICH ARCHIPELAGO.

HAWAII; in the chart in Freycinet's "Atlas," small portions of the coast
are fringed by reefs; and in the accompanying "Hydrog. Memoir," reefs are
mentioned in several places, and the coral is said to injure the cables.
On one side of the islet of Kohaihai there is a bank of sand and coral with
five feet water on it, running parallel to the shore, and leaving a channel
of about fifteen feet deep within.  I have coloured this island red, but it
is very much less perfectly fringed than others of the group.--MAUI; in
Freycinet's chart of the anchorage of Raheina, two or three miles of coast
are seen to be fringed; and in the "Hydrog. Memoir," "banks of coral along
shore" are spoken of.  Mr. F.D. Bennett informs me that the reefs, on an
average, extend about a quarter of a mile from the beach; the land is not
very steep, and outside the reefs the sea does not become deep very
suddenly; coloured red.--MOROTOI, I presume, is fringed: Freycinet speaks
of the breakers extending along the shore at a little distance from it.
From the chart, I believe it is fringed; coloured red.--OAHU; Freycinet, in
his "Hydrog. Memoir," mentions some of the reefs.  Mr. F.D. Bennett informs
me that the shore is skirted for forty or fifty miles in length.  There is
even a harbour for ships formed by the reefs, but it is at the mouth of a
valley; red.--ATOOI, in La Peyrouse's charts, is represented as fringed by
a reef, in the same manner as Oahu and Morotoi; and this, as I have been
informed by Mr. Ellis, on part at least of the shore, is of coral-formation:
the reef does not leave a deep channel within; red.--ONEEHOW;
Mr. Ellis believes that this island is also fringed by a coral-reef:
considering its close proximity to the other islands, I have ventured to
colour it red.  I have in vain consulted the works of Cook, Vancouver, La
Peyrouse, and Lisiansky, for any satisfactory account of the small islands
and reefs, which lie scattered in a N.W. line prolonged from the Sandwich
group, and hence have left them uncoloured, with one exception; for I am
indebted to Mr. F.D. Bennett for informing me of an atoll-formed reef, in
latitude 28 deg 22', longitude 178 deg 30' W., on which the "Gledstanes"
was wrecked in 1837.  It is apparently of large size, and extends in a N.W.
and S.E. line: very few islets have been formed on it.  The lagoon seems
to be shallow; at least, the deepest part which was surveyed was only three
fathoms.  Mr. Couthouy ("Remarks," page 38) describes this island under the
name of OCEAN island.  Considerable doubts should be entertained regarding
the nature of a reef of this kind, with a very shallow lagoon, and standing
far from any other atoll, on account of the possibility of a crater or flat
bank of rock lying at the proper depth beneath the surface of the water,
thus affording a foundation for a ring-formed coral-reef.  I have, however,
thought myself compelled, from its large size and symmetrical outline, to
colour it blue.

SAMOA OR NAVIGATOR GROUP.

Kotzebue, in his "Second Voyage," contrasts the structure of these islands
with many others in the Pacific, in not being furnished with harbours for
ships, formed by distant coral-reefs.  The Rev. J. Williams, however,
informs me, that coral-reefs do occur in irregular patches on the shores of
these islands; but that they do not form a continuous band, as round
Mangaia, and other such perfect cases of fringed islands.  From the charts
accompanying La Peyrouse's "Voyage," it appears that the north shore of
SAVAII, MAOUNA, OROSENGA, and MANUA, are fringed by reefs.  La Peyrouse,
speaking of Maouna (page 126), says that the coral-reef surrounding its
shores, almost touches the beach; and is breached in front of the little
coves and streams, forming passages for canoes, and probably even for
boats.  Further on (page 159), he extends the same observation to all the
islands which he visited.  Mr. Williams in his "Narrative," speaks of a
reef going round a small island attached to OYOLAVA, and returning again to
it: all these islands have been coloured red.--A chart of ROSE Island, at
the extreme west end of the group, is given by Freycinet, from which I
should have thought that it had been an atoll; but according to Mr.
Couthouy ("Remarks," page 43), it consists of a reef, only a league in
circuit, surmounted by a very few low islets; the lagoon is very shallow,
and is strewed with numerous large boulders of volcanic rock.  This island,
therefore, probably consists of a bank of rock, a few feet submerged, with
the outer margin of its upper surface fringed with reefs; hence it cannot
be properly classed with atolls, in which the foundations are always
supposed to lie at a depth, greater than that at which the reef-constructing
polypifers can live; not coloured.

BEVERIDGE Reef, 20 deg S., 167 deg W., is described in the "Naut. Mag."
(May 1833, page 442) as ten miles long in a N. and S. line, and eight wide;
"in the inside of the reef there appears deep water;" there is a passage
near the S.W. corner: this therefore seems to be a submerged atoll, and is
coloured blue.

SAVAGE Island, 19 deg S., 170 deg W., has been described by Cook and
Forster.  The younger Forster (volume ii., page 163) says it is about forty
feet high: he suspects that it contains a low plain, which formerly was
the lagoon.  The Rev. J. Williams informs me that the reef fringing its
shores, resembles that round Mangaia; coloured red.

FRIENDLY ARCHIPELAGO.

PYLSTAART Island.  Judging from the chart in Freycinet's "Atlas," I should
have supposed that it had been regularly fringed; but as nothing is said in
the "Hydrog. Memoir" (or in the "Voyage" of Tasman, the discoverer) about
coral-reefs, I have left it uncoloured.--TONGATABOU: In the "Atlas of the
Voyage of the 'Astrolabe'," the whole south side of the island is
represented as narrowly fringed by the same reef which forms an extensive
platform on the northern side.  The origin of this latter reef, which might
have been mistaken for a barrier-reef, has already been attempted to be
explained, when giving the proofs of the recent elevation of this island.--
In Cook's charts the little outlying island also of EOAIGEE, is represented
as fringed; coloured red.--EOUA.  I cannot make out from Captain Cook's
charts and descriptions, that this island has any reef, although the bottom
of the neighbouring sea seems to be corally, and the island itself is
formed of coral-rock.  Forster, however, distinctly ("Observations," page
14) classes it with high islands having reefs, but it certainly is not
encircled by a barrier-reef and the younger Forster ("Voyage," volume i.,
page 426) says, that "a bed of coral-rocks surrounded the coast towards the
landing-place."  I have therefore classed it with the fringed islands and
coloured it red.  The several islands lying N.W. of Tongatabou, namely
ANAMOUKA, KOMANGO, KOTOU, LEFOUGA, FOA, etc., are seen in Captain Cook's
chart to be fringed by reefs, in several of them are connected together.
From the various statements in the first volume of Cook's "Third Voyage,"
and especially in the fourth and sixth chapters, it appears that these
reefs are of coral-formation, and certainly do not belong to the barrier
class; coloured red.--TOUFOA AND KAO, forming the western part of the
group, according to Forster have no reefs; the former is an active
volcano.--VAVAO.  There is a chart of this singularly formed island, by
Espinoza: according to Mr. Williams it consists of coral-rock: the
Chevalier Dillon informs me that it is not fringed; not coloured.  Nor are
the islands of LATTE and AMARGURA, for I have not seen plans on a large
scale of them, and do not know whether they are fringed.

NIOUHA, 16 deg S., 174 deg W., or KEPPEL Island of Wallis, or COCOS Island.
From a view and chart of this island given in Wallis's "Voyage" (4to
edition) it is evidently encircled by a reef; coloured blue: it is however
remarkable that BOSCAWEN Island, immediately adjoining, has no reef of any
kind; uncoloured.

WALLIS Island, 13 deg S., 176 deg W., a chart and view of this island in
Wallis's "Voyage" (4to edition) shows that it is encircled.  A view of it
in the "Naut. Mag." July 1833, page 376, shows the same fact; blue.

ALLOUFATOU, or HORN Island, ONOUAFU, or PROBY Island, and HUNTER Islands,
lie between the Navigator and Fidji groups.  I can find no distinct
accounts of them.

FIDJI or VITI GROUP.

The best chart of the numerous islands of this group, will be found in the
"Atlas of the 'Astrolabe's' Voyage."  From this, and from the description
given in the "Hydrog. Memoir," accompanying it, it appears that many of
these islands are bold and mountainous, rising to the height of between
3,000 and 4,000 feet.  Most of the islands are surrounded by reefs, lying
far from the land, and outside of which the ocean appears very deep.  The
"Astrolabe" sounded with ninety fathoms in several places about a mile from
the reefs, and found no bottom.  Although the depth within the reef is not
laid down, it is evident from several expressions, that Captain D'Urville
believes that ships could anchor within, if passages existed through the
outer barriers.  The Chevallier Dillon informs me that this is the case:
hence I have coloured this group blue.  In the S.E. part lies BATOA, or
TURTLE Island of Cook ("Second Voyage," volume ii., page 23, and chart, 4to
edition) surrounded by a coral-reef, "which in some places extends two
miles from the shore;" within the reef the water appears to be deep, and
outside it is unfathomable; coloured pale blue.  At the distance of a few
miles, Captain Cook (Ibid., page 24) found a circular coral-reef, four or
five leagues in circuit, with deep water within; "in short, the bank wants
only a few little islets to make it exactly like one of the half-drowned
isles so often mentioned,"--namely, atolls.  South of Batoa, lies the high
island of ONO, which appears in Bellinghausen's "Atlas" to be encircled; as
do some other small islands to the south; coloured pale blue; near Ono,
there is an annular reef, quite similar to the one just described in the
words of Captain Cook; coloured dark blue.

ROTOUMAH, 13 deg S., 179 deg E.--From the chart in Duperrey's "Atlas," I
thought this island was encircled, and had coloured it blue, but the
Chevallier Dillon assures me that the reef is only a shore or fringing one;
red.

INDEPENDENCE Island, 10 deg S., 179 deg E., is described by Mr. G. Bennett,
("United Service Journal," 1831, part ii., page 197) as a low island of
coral-formation, it is small, and does not appear to contain a lagoon,
although an opening through the reef is referred to.  A lagoon probably
once existed, and has since been filled up; left uncoloured.

ELLICE GROUP.

OSCAR, PEYSTER, and ELLICE Islands are figured in Arrowsmith's "Chart of
the Pacific" (corrected to 1832) as atolls, and are said to be very low;
blue.--NEDERLANDISCH Island.  I am greatly indebted to the kindness of
Admiral Krusenstern, for sending me the original documents concerning this
island.  From the plans given by Captains Eeg and Khremtshenko, and from
the detailed account given by the former, it appears that it is a narrow
coral-island, about two miles long, containing a small lagoon.  The sea is
very deep close to the shore, which is fronted by sharp coral-rocks.
Captain Eeg compares the lagoon with that of other coral-islands; and he
distinctly says, the land is "very low."  I have therefore coloured it
blue.  Admiral Krusenstern ("Memoir on the Pacific," Append., 1835) states
that its shores are eighty feet high; this probably arose from the height
of the cocoa-nut trees, with which it is covered, being mistaken for land.
--GRAN COCAL is said in Krusenstern's "Memoir," to be low, and to be
surrounded by a reef; it is small, and therefore probably once contained a
lagoon; uncoloured.--ST. AUGUSTIN.  From a chart and view of it, given in
the "Atlas of the 'Coquille's' Voyage," it appears to be a small atoll,
with its lagoon partly filled up; coloured blue.

GILBERT GROUP.

The chart of this group, given in the "Atlas of the 'Coquille's' Voyage,"
at once shows that it is composed of ten well characterised atolls.  In
D'Urville and Lottin's chart, SYDENHAM is written with a capital letter,
signifying that it is high; but this certainly is not the case, for it is a
perfectly characterised atoll, and a sketch, showing how low it is, is
given in the "'Coquille's' Atlas."  Some narrow strip-like reefs project
from the southern side of DRUMMOND atoll, and render it irregular.  The
southern island of the group is called CHASE (in some charts, ROTCHES); of
this I can find no account, but Mr. F.D. Bennett discovered ("Geographical
Journal", volume vii., page 229), a low extensive island in nearly the same
latitude, about three degrees westward of the longitude assigned to
Rotches, but very probably it is the same island.  Mr. Bennett informs me
that the man at the masthead reported an appearance of lagoon-water in the
centre; and, therefore, considering its position, I have coloured it blue.
--PITT Island, at the extreme northern point of the group, is left
uncoloured, as its exact position and nature is not known.--BYRON Island,
which lies a little to the eastward, does not appear to have been visited
since Commodore Byron's voyage, and it was then seen only from a distance
of eighteen miles; it is said to be low; uncoloured.

OCEAN, PLEASANT, and ATLANTIC Islands all lie considerably to the west of
the Gilbert group: I have been unable to find any distinct account of
them.  Ocean Island is written with small letters in the French chart, but
in Krusenstern's "Memoir" it is said to be high.

MARSHALL GROUP.

We are well acquainted with this group from the excellent charts of the
separate islands, made during the two voyages of Kotzebue: a reduced one
of the whole group may be easily seen in Krusenstern's "Atlas," and in
Kotzebue's "Second Voyage."  The group consists (with the exception of two
LITTLE islands which probably have had their lagoon filled up) of a double
row of twenty-three large and well-characterised atolls, from the
examination of which Chamisso has given us his well-known account of
coral-formations.  I include GASPAR RICO, or CORNWALLIS Island in this group,
which is described by Chamisso (Kotzebue's "First Voyage," volume iii.,
page 179) "as a low sickle-formed group, with mould only on the windward
side."  Gaspard Island is considered by some geographers as a distinct
island lying N.E. of the group, but it is not entered in the chart by
Krusenstern; left uncoloured.  In the S.W. part of this group lies BARING
Island, of which little is known (see Krusenstern's "Appendix," 1835, page
149).  I have left it uncoloured; but BOSTON Island I have coloured blue,
as it is described (Ibid.) as consisting of fourteen small islands, which,
no doubt, enclose a lagoon, as represented in a chart in the "'Coquille's'
Atlas."--Two islands, AUR KAWEN and GASPAR RICO, are written in the French
chart with capital letters; but this is an error, for from the account
given by Chamisso in Kotzebue's "First Voyage," they are certainly low.
The nature, position, and even existence, of the shoals and small islands
north of the Marshall group, are doubtful.

NEW HEBRIDES.

Any chart, on even a small scale, of these islands, will show that their
shores are almost without reefs, presenting a remarkable contrast with
those of New Caledonia on the one hand, and the Fidji group on the other.
Nevertheless, I have been assured by Mr. G. Bennett, that coral grows
vigorously on their shores; as indeed, will be further shown in some of the
following notices.  As, therefore, these islands are not encircled, and as
coral grows vigorously on their shores, we might almost conclude, without
further evidence, that they were fringed, and hence I have applied the red
colour with rather greater freedom than in other instances.--MATTHEW'S
ROCK, an active volcano, some way south of the group (of which a plan is
given in the "Atlas of the 'Astrolabe's' Voyage") does not appear to have
reefs of any kind about it.--ANNATOM, the southernmost of the Hebrides;
from a rough woodcut given in the "United Service Journal" (1831, part
iii., page 190), accompanying a paper by Mr. Bennett, it appears that the
shore is fringed; coloured red.--TANNA.  Forster, in his "Observations"
(page 22), says Tanna has on its shores coral-rock and madrepores; and the
younger Forster, in his account (volume ii., page 269) speaking of the
harbour says, the whole S.E. side consists of coral-reefs, which are
overflowed at high-water; part of the southern shore in Cook's chart is
represented as fringed; coloured red.--IMMER is described ("United Service
Journal," 1831, part iii., page 192) by Mr. Bennett as being of moderate
elevation, with cliffs appearing like sandstone: coral grows in patches on
its shore, but I have not coloured it; and I mention these facts, because
Immer might have been thought from Forster's classification
("Observations," page 14), to have been a low island or even an atoll.--
ERROMANGO Island; Cook ("Second Voyage," volume ii., page 45, 4to edition)
speaks of rocks everywhere LINING the coast, and the natives offered to
haul his boat over the breakers to the sandy beach: Mr. Bennett, in a
letter to the Editor of the "Singapore Chron.," alludes to the REEFS on its
shores.  It may, I think, be safely inferred from these passages that the
shore is fringed in parts by coral-reefs; coloured red.--SANDWICH Island.
The east coast is said (Cook's "Second Voyage," volume ii., page 41) to be
low, and to be guarded by a chain of breakers.  In the accompanying chart
it is seen to be fringed by a reef; coloured red.--MALLICOLLO.  Forster
speaks of the reef-bounded shore: the reef is about thirty yards wide, and
so shallow that a boat cannot pass over it.  Forster also ("Observations,"
page 23) says, that the rocks of the sea-shore consist of madrepore.  In
the plan of Sandwich harbour, the headlands are represented as fringed;
coloured red.--AURORA and PENTECOST Islands, according to Bougainville,
apparently have no reefs; nor has the large island of S. ESPIRITU, nor
BLIGH Island or BANKS' Islands, which latter lie to the N.E. of the
Hebrides.  But in none of these cases, have I met with any detailed account
of their shores, or seen plans on a large scale; and it will be evident,
that a fringing-reef of only thirty or even a few hundred yards in width,
is of so little importance to navigation, that it will seldom be noticed,
excepting by chance; and hence I do not doubt that several of these
islands, now left uncoloured, ought to be red.

SANTA CRUZ GROUP.

VANIKORO (Figure 1, Plate I.) offers a striking example of a barrier-reef:
it was first described by the Chevalier Dillon, in his voyage, and was
surveyed in the "Astrolabe"; coloured pale blue.--TIKOPIA and FATAKA
Islands appear, from the descriptions of Dillon and D'Urville, to have no
reefs; ANOUDA is a low, flat island, surrounded by cliffs ("'Astrolabe'
Hydrog." and Krusenstern, "Mem." volume ii., page 432); these are
uncoloured.  TOUPOUA (OTOOBOA of Dillon) is stated by Captain Tromelin
("Annales Marit." 1829, page 289) to be almost entirely included in a reef,
lying at the distance of two miles from the shore.  There is a space of
three miles without any reef, which, although indented with bays, offers no
anchorage from the extreme depth of the water close to the shore: Captain
Dillon also speaks of the reefs fronting this island; coloured blue.--
SANTA-CRUZ.  I have carefully examined the works of Carteret,
D'Entrecasteaux, Wilson, and Tromelin, and I cannot discover any mention of
reefs on its shores; left uncoloured.--TINAKORO is a constantly active
volcano without reefs.--MENDANA ISLES (mentioned by Dillon under the name
of MAMMEE, etc.); said by Krusenstern to be low, and intertwined with
reefs.  I do not believe they include a lagoon; I have left them
uncoloured.--DUFF'S Islands compose a small group directed in a N.W. and
S.E. band; they are described by Wilson (page 296, "Miss. Voy." 4to
edition), as formed by bold-peaked land, with the islands surrounded by
coral-reefs, extending about half a mile from the shore; at a distance of a
mile from the reefs he found only seven fathoms.  As I have no reason for
supposing there is deep water within these reefs, I have coloured them red.
KENNEDY Island, N.E. of Duff's.  I have been unable to find any account of
it.

NEW CALEDONIA.

The great barrier-reefs on the shores of this island have already been
described (Figure 5, Plate II.).  They have been visited by Labillardiere,
Cook, and the northern point by D'Urville; this latter part so closely
resembles an atoll that I have coloured it dark blue.  The LOYALTY group is
situated eastward of this island; from the chart and description given in
the "Voyage of the 'Astrolabe'," they do not appear to have any reefs;
north of this group, there are some extensive low reefs (called ASTROLABE
and BEAUPRE,) which do not seem to be atoll-formed; these are left
uncoloured.

AUSTRALIAN BARRIER-REEF.

The limits of this great reef, which has already been described, have been
coloured from the charts of Flinders and King.  In the northern parts, an
atoll-formed reef, lying outside the barrier, has been described by Bligh,
and is coloured dark blue.  In the space between Australia and New
Caledonia, called by Flinders the Corallian Sea, there are numerous reefs.
Of these, some are represented in Krusenstern's "Atlas" as having an
atoll-like structure; namely, BAMPTON shoal, FREDERIC, VINE or Horse-shoe,
and ALERT reefs; these have been coloured dark blue.

LOUISIADE.

The dangerous reefs which front and surround the western, southern, and
northern coasts of this so-called peninsula and archipelago, seem evidently
to belong to the barrier class.  The land is lofty, with a low fringe on
the coast; the reefs are distant, and the sea outside them profoundly deep.
Nearly all that is known of this group is derived from the labours of
D'Entrecasteaux and Bougainville: the latter has represented one
continuous reef ninety miles long, parallel to the shore, and in places as
much as ten miles from it; coloured pale blue.  A little distance northward
we have the LAUGHLAN Islands, the reefs round which are engraved in the
"Atlas of the Voyage of the 'Astrolabe'," in the same manner as in the
encircled islands of the Caroline Archipelago, the reef is, in parts, a
mile and a half from the shore, to which it does not appear to be attached;
coloured blue.  At some little distance from the extremity of the Louisiade
lies the WELLS reef, described in G. Hamilton's "Voyage in H.M.S.
'Pandora'" (page 100): it is said, "We found we had got embayed in a
double reef, which will soon be an island."  As this statement is only
intelligible on the supposition of the reef being crescent or horse-shoe
formed, like so many other submerged annular reefs, I have ventured to
colour it blue.

SOLOMON ARCHIPELAGO.

The chart in Krusenstern's "Atlas" shows that these islands are not
encircled, and as coral appears from the works of Surville, Bougainville,
and Labillardiere, to grow on their shores, this circumstance, as in the
case of the New Hebrides, is a presumption that they are fringed.  I cannot
find out anything from D'Entrecasteaux's "Voyage," regarding the southern
islands of the group, so have left them uncoloured.--MALAYTA Island in a
rough MS. chart in the Admiralty has its northern shore fringed.--YSABEL
Island, the N.E. part of this island, in the same chart, is also fringed:
Mendana, speaking (Burney, volume i., page 280) of an islet adjoining the
northern coast, says it is surrounded by reefs; the shores, also of Port
Praslin appear regularly fringed.--CHOISEUL Island.  In Bougainville's
"Chart of Choiseul Bay," parts of the shores are fringed by coral-reefs.--
BOUGAINVILLE Island.  According to D'Entrecasteaux the western shore
abounds with coral-reefs, and the smaller islands are said to be attached
to the larger ones by reefs; all the before-mentioned islands have been
coloured red.--BOUKA Islands.  Captain Duperrey has kindly informed me in a
letter that he passed close round the northern side of this island (of
which a plan is given in his "Atlas of the 'Coquille's' Voyage"), and that
it was "garnie d'une bande de recifs a fleur d'eau adherentes au rivage;"
and he infers, from the abundance of coral on the islands north and south
of Bouka, that the reef probably is of coral; coloured red.

Off the north coast of the Solomon Archipelago there are several small
groups which are little known; they appear to be low, and of
coral-formation; and some of them probably have an atoll-like structure; the
Chevallier Dillon, however, informs me that this is not the case with the
B. de CANDELARIA.--OUTONG JAVA, according to the Spanish navigator,
Maurelle, is thus characterised; but this is the only one which I have
ventured to colour blue.

NEW IRELAND.

The shores of the S.W. point of this island and some adjoining islets, are
fringed by reefs, as may be seen in the "Atlases of the Voyages of the
'Coquille' and 'Astrolabe'."  M. Lesson observes that the reefs are open in
front of each streamlet.  The DUKE OF YORK'S Island is also fringed; but
with regard to the other parts of NEW IRELAND, NEW HANOVER, and the small
islands lying northward, I have been unable to obtain any information.  I
will only add that no part of New Ireland appears to be fronted by distant
reefs.  I have coloured red only the above specified portions.

NEW BRITAIN AND THE NORTHERN SHORE OF NEW GUINEA.

From the charts in the "Voyage of the 'Astrolabe'," and from the "Hydrog.
Memoir," it appears that these coasts are entirely without reefs, as are
the SCHOUTEN Islands, lying close to the northern shore of New Guinea.  The
western and south-western parts of New Guinea, will be treated of when we
come to the islands of the East Indian Archipelago.

ADMIRALTY GROUP.

From the accounts by Bougainville, Maurelle, D'Entrecasteaux, and the
scattered notices collected by Horsburgh, it appears, that some of the many
islands composing it, are high, with a bold outline; and others are very
low, small and interlaced with reefs.  All the high islands appear to be
fronted by distant reefs rising abruptly from the sea, and within some of
which there is reason to believe that the water is deep.  I have therefore
little doubt they are of the barrier class.--In the southern part of the
group we have ELIZABETH Island, which is surrounded by a reef at the
distance of a mile; and two miles eastward of it (Krusenstern, "Append."
1835, page 42) there is a little island containing a lagoon.--Near here,
also lies CIRCULAR-REEF (Horsburgh, "Direct." volume i., page 691, 4th
edition), "three or four miles in diameter having deep water inside with an
opening at the N.N.W. part, and on the outside steep to."  I have from
these data, coloured the group pale blue, and CIRCULAR-REEF dark blue.--the
ANACHORITES, ECHEQUIER, and HERMITES, consist of innumerable low islands of
coral-formation, which probably have atoll-like forms; but not being able
to ascertain this, I have not coloured them, nor DUROUR Island, which is
described by Carteret as low.

The CAROLINE ARCHIPELAGO is now well-known, chiefly from the hydrographical
labours of Lutke; it contains about forty groups of atolls, and three
encircled islands, two of which are engraved in Figures 2 and 7, Plate I.
Commencing with the eastern part; the encircling reef round UALEN appears
to be only about half a mile from the shore; but as the land is low and
covered with mangroves ("Voyage autour du Monde," par F. Lutke, volume i.,
page 339), the real margin has not probably been ascertained.  The extreme
depth in one of the harbours within the reef is thirty-three fathoms (see
charts in "Atlas of 'Coquille's' Voyage"), and outside at half a mile
distant from the reef, no bottom was obtained with two hundred and fifty
fathoms.  The reef is surmounted by many islets, and the lagoon-like
channel within is mostly shallow, and appears to have been much encroached
on by the low land surrounding the central mountains; these facts show that
time has allowed much detritus to accumulate; coloured pale blue.--
POUYNIPETE, or Seniavine.  In the greater part of the circumference of this
island, the reef is about one mile and three quarters distant; on the north
side it is five miles off the included high islets.  The reef is broken in
several places; and just within it, the depth in one place is thirty
fathoms, and in another, twenty-eight, beyond which, to all appearance,
there was "un porte vaste et sur" (Lutke, volume ii., page 4); coloured
pale blue.--HOGOLEU or ROUG.  This wonderful group contains at least
sixty-two islands, and its reef is one hundred and thirty-five miles in
circuit.  Of the islands, only a few, about six or eight (see "Hydrog.
Descrip." page 428, of the "Voyage of the 'Astrolabe'," and the large
accompanying chart taken chiefly from that given by Duperrey) are high, and
the rest are all small, low, and formed on the reef.  The depth of the great
interior lake has not been ascertained; but Captain D'Urville appears to have
entertained no doubt about the possibility of taking in a frigate.  The
reef lies no less than fourteen miles distant from the northern coasts of
the interior high islands, seven from their western sides, and twenty from
the southern; the sea is deep outside.  This island is a likeness on a
grand scale to the Gambier group in the Low Archipelago.  Of the groups of
low (In D'Urville and Lottin's chart, Peserare is written with capital
letters; but this evidently is an error, for it is one of the low islets on
the reef of Namonouyto (see Lutke's charts)--a regular atoll.) islands
forming the chief part of the Caroline Archipelago, all those of larger
size, have the true atoll-structure (as may be seen in the "Atlas" by
Captain Lutke), and some even of the very small ones, as MACASKILL and
DUPERREY, of which plans are given in the "Atlas of the 'Coquille's'
Voyage."  There are, however, some low small islands of coral-formation,
namely OLLAP, TAMATAM, BIGALI, SATAHOUAL, which do not contain lagoons; but
it is probable that lagoons originally existed, but have since filled up:
Lutke (volume ii., page 304) seems to have thought that all the low
islands, with only one exception, contained lagoons.  From the sketches,
and from the manner in which the margins of these islands are engraved in
the "Atlas of the Voyage of the 'Coquille'," it might have been thought
that they were not low; but by a comparison with the remarks of Lutke
(volume ii., page 107, regarding Bigali) and of Freycinet ("Hydrog. Memoir
'L'Uranie' Voyage," page 188, regarding Tamatam, Ollap, etc.), it will be
seen that the artist must have represented the land incorrectly.  The most
southern island in the group, namely PIGUIRAM, is not coloured, because I
have found no account of it.  NOUGOUOR, or MONTE VERDISON, which was not
visited by Lutke, is described and figured by Mr. Bennett ("United Service
Journal," January 1832) as an atoll.  All the above-mentioned islands have
been coloured blue.

WESTERN PART OF THE CAROLINE ARCHIPELAGO.

FAIS Island is ninety feet high, and is surrounded, as I have been informed
by Admiral Lutke, by a narrow reef of living coral, of which the broadest
part, as represented in the charts, is only 150 yards; coloured red.--
PHILIP Island., I believe, is low; but Hunter, in his "Historical Journal,"
gives no clear account of it; uncoloured.--ELIVI; from the manner in which
the islets on the reefs are engraved, in the "Atlas of the 'Astrolabe's'
Voyage," I should have thought they were above the ordinary height, but
Admiral Lutke assures me this is not the case: they form a regular atoll;
coloured blue.--GOUAP (EAP of Chamisso), is a high island with a reef (see
chart in "Voyage of the 'Astrolabe'"), more than a mile distant in most
parts from the shore, and two miles in one part.  Captain D'Urville thinks
that there would be anchorage ("Hydrog. Descript. 'Astrolabe' Voyage," page
436) for ships within the reef, if a passage could be found; coloured pale
blue.--GOULOU, from the chart in the "'Astrolabe's' Atlas," appears to be
an atoll.  D'Urville ("Hydrog. Descript." page 437) speaks of the low
islets on the reef; coloured dark blue.

PELEW ISLANDS.

Krusenstern speaks of some of the islands being mountainous; the reefs are
distant from the shore, and there are spaces within them, and not opposite
valleys, with from ten to fifteen fathoms.  According to a MS. chart of the
group by Lieutenant Elmer in the Admiralty, there is a large space within
the reef with deepish water; although the high land does not hold a central
position with respect to the reefs, as is generally the case, I have little
doubt that the reefs of the Pelew Islands ought to be ranked with the
barrier class, and I have coloured them pale blue.  In Lieutenant Elmer's
chart there is a horseshoe-formed shoal, laid down thirteen miles N.W. of
Pelew, with fifteen fathoms within the reef, and some dry banks on it;
coloured dark blue.--SPANISH, MARTIRES, SANSEROT, PULO ANNA and MARIERE
Islands are not coloured, because I know nothing about them, excepting that
according to Krusenstern, the second, third, and fourth mentioned, are low,
placed on coral-reefs, and therefore, perhaps, contain lagoons; but Pulo
Mariere is a little higher.

MARIANA ARCHIPELAGO, or LADRONES.

GUAHAN.  Almost the whole of this island is fringed by reefs, which extend
in most parts about a third of a mile from the land.  Even where the reefs
are most extensive, the water within them is shallow.  In several parts
there is a navigable channel for boats and canoes within the reefs.  In
Freycinet's "Hydrog. Mem." there is an account of these reefs, and in the
"Atlas," a map on a large scale; coloured red.--ROTA.  "L'ile est presque
entierement entouree des recifs" (page 212, Freycinet's "Hydrog. Mem.").
These reefs project about a quarter of a mile from the shore; coloured
red.--TINIAN.  THE EASTERN coast is precipitous, and is without reefs; but
the western side is fringed like the last island; coloured red.--SAYPAN.
The N.E. coast, and likewise the western shores appear to be fringed; but
there is a great, irregular, horn-like reef projecting far from this side;
coloured red.--FARALLON DE MEDINILLA, appears so regularly and closely
fringed in Freycinet's charts, that I have ventured to colour it red,
although nothing is said about reefs in the "Hydrographical Memoir."  The
several islands which form the northern part of the group are volcanic
(with the exception perhaps of Torres, which resembles in form the
madreporitic island of Medinilla), and appear to be without reefs.--MANGS,
however, is described (by Freycinet, page 219, "Hydrog.") from some Spanish
charts, as formed of small islands placed "au milieu des nombreux recifs;"
and as these reefs in the general chart of the group do not project so much
as a mile; and as there is no appearance from a double line, of the
existence of deep water within, I have ventured, although with much
hesitation, to colour them red.  Respecting FOLGER and MARSHALL Islands
which lie some way east of the Marianas, I can find out nothing, excepting
that they are probably low.  Krusenstern says this of Marshall Island; and
Folger Island is written with small letters in D'Urville's chart;
uncoloured.

BONIN OR ARZOBISPO GROUP.

PEEL Island has been examined by Captain Beechey, to whose kindness I am
much indebted for giving me information regarding it: "At Port Lloyd there
is a great deal of coral; and the inner harbour is entirely formed by
coral-reefs, which extend outside the port along the coast."  Captain
Beechey, in another part of his letter to me, alludes to the reefs fringing
the island in all directions; but at the same time it must be observed that
the surf washes the volcanic rocks of the coast in the greater part of its
circumference.  I do not know whether the other islands of the Archipelago
are fringed; I have coloured Peel Island red.--GRAMPUS Island to the
eastward, does not appear (Meare's "Voyage," page 95) to have any reefs,
nor does ROSARIO Island (from Lutke's chart), which lies to the westward.
Respecting the few other islands in this part of the sea, namely the
SULPHUR Islands, with an active volcano, and those lying between Bonin and
Japan (which are situated near the extreme limit in latitude, at which
reefs are formed), I have not been able to find any clear account.

WEST END OF NEW GUINEA.

PORT DORY.  From the charts in the "Voyage of the 'Coquille'," it would
appear that the coast in this part is fringed by coral-reefs; M. Lesson,
however, remarks that the coral is sickly; coloured red.--WAIGIOU.  A
considerable portion of the northern shores of these islands is seen in the
charts (on a large scale) in Freycinet's "Atlas" to be fringed by
coral-reefs.  Forrest (page 21, "Voyage to New Guinea") alludes to the
coral-reefs lining the heads of Piapis Bay; and Horsburgh (volume ii., page
599, 4th edition), speaking of the islands in Dampier Strait, says "sharp
coral-rocks line their shores;" coloured red.--In the sea north of these
islands, we have GUEDES (or FREEWILL, or ST. DAVID'S), which from the chart
given in the 4to edition of Carteret's "Voyage," must be an atoll.
Krusenstern says the islets are very low; coloured blue.--CARTERET'S SHOALS,
in 2 deg 53' N., are described as circular, with stony points showing all
round, with deeper water in the middle; coloured blue.--AIOU; the plan of
this group, given in the "Atlas of the Voyage of the 'Astrolabe'," shows that
it is an atoll; and, from a chart in Forrest's "Voyage," it appears that
there is twelve fathoms within the circular reef; coloured blue.--The S.W.
coast of New Guinea appears to be low, muddy, and devoid of reefs.  The ARRU,
TIMOR-LAUT, and TENIMBER groups have lately been examined by Captain Kolff,
the MS. translation of which, by Mr. W. Earl, I have been permitted to read,
through the kindness of Captain Washington, R.N.  These islands are mostly
rather low, and are surrounded by distant reefs (the Ki Islands, however,
are lofty, and, from Mr. Stanley's survey, appear without reefs); the sea
in some parts is shallow, in others profoundly deep (as near Larrat).  From
the imperfection of the published charts, I have been unable to decide to
which class these reefs belong.  From the distance to which they extend
from the land, where the sea is very deep, I am strongly inclined to
believe they ought to come within the barrier class, and be coloured blue;
but I have been forced to leave them uncoloured.--The last-mentioned groups
are connected with the east end of Ceram by a chain of small islands, of
which the small groups of CERAM-LAUT, GORAM and KEFFING are surrounded by
very extensive reefs, projecting into deep water, which, as in the last
case, I strongly suspect belong to the barrier class; but I have not
coloured them.  From the south side of Keffing, the reefs project five
miles (Windsor Earl's "Sailing Direct. for the Arafura Sea," page 9).

CERAM.

In various charts which I have examined, several parts of the coast are
represented as fringed by reefs.--MANIPA Island, between Ceram and Bourou,
in an old MS. chart in the Admiralty, is fringed by a very irregular reef,
partly dry at low water, which I do not doubt is of coral-formation; both
islands coloured red.--BOUROU; parts of this island appear fringed by
coral-reefs, namely, the eastern coast, as seen in Freycinet's chart; and
CAJELI BAY, which is said by Horsburgh (volume ii., page 630) to be lined
by coral-reefs, that stretch out a little way, and have only a few feet
water on them.  In several charts, portions of the islands forming the
AMBOINA GROUP are fringed by reefs; for instance, NOESSA, HARENCA, and
UCASTER, in Freycinet's charts.  The above-mentioned islands have been
coloured red, although the evidence is not very satisfactory.--North of
Bourou the parallel line of the XULLA Isles extends: I have not been able
to find out anything about them, excepting that Horsburgh (volume ii., page
543) says that the northern shore is surrounded by a reef at the distance
of two or three miles; uncoloured.--MYSOL GROUP; the Kanary Islands are
said by Forrest ("Voyage," page 130) to be divided from each other by deep
straits, and are lined with coral-rocks; coloured red.--GUEBE, lying
between Waigiou and Gilolo, is engraved as if fringed; and it is said by
Freycinet, that all the soundings under five fathoms were on coral;
coloured red.--GILOLO.  In a chart published by Dalrymple, the numerous
islands on the western, southern (BATCHIAN and the STRAIT OF PATIENTIA),
and eastern sides appear fringed by narrow reefs; these reefs, I suppose,
are of coral, for it is said in "Malte Brun" (volume xii., page 156), "Sur
les cotes (of Batchian) comme DANS LES PLUPART des iles de cet archipel, il
y a de rocs de medrepores d'une beaute et d'une variete infimies."
Forrest, also (page 50), says Seland, near Batchian, is a little island
with reefs of coral; coloured red.--MORTY Island (north of Gilolo).
Horsburgh (volume ii., page 506) says the northern coast is lined by reefs,
projecting one or two miles, and having no soundings close to them; I have
left it uncoloured, although, as in some former cases, it ought probably to
be pale blue.--CELEBES.  The western and northern coasts appear in the
charts to be bold and without reefs.  Near the extreme northern point,
however, an islet in the STRAITS OF LIMBE, and parts of the adjoining
shore, appear to be fringed: the east side of the bay of MANADO, has deep
water, and is fringed by sand and coral ("'Astrol.' Voyage," Hydrog. Part,
pages 453-4); this extreme point, therefore, I have coloured red.--Of the
islands leading from this point to Magindanao, I have not been able to find
any account, except of SERANGANI, which appears surrounded by narrow reefs;
and Forrest ("Voyage," page 164) speaks of coral on its shores; I have,
therefore, coloured this island red.  To the eastward of this chain lie
several islands; of which I cannot find any account, except of KARKALANG,
which is said by Horsburgh (volume ii., page 504) to be lined by a
dangerous reef, projecting several miles from the northern shore; not
coloured.

ISLANDS NEAR TIMOR.

The account of the following islands is taken from Captain D. Kolff's
"Voyage," in 1825, translated by Mr. W. Earl, from the Dutch.--LETTE has
"reefs extending along shore at the distance of half a mile from the
land."--MOA has reefs on the S.W. part.--LAKOR has a reef lining its shore;
these islands are coloured red.--Still more eastward, LUAN has, differently
from the last-mentioned islands, an extensive reef; it is steep outside,
and within there is a depth of twelve feet; from these facts, it is
impossible to decide to which class this island belongs.--KISSA, off the
point of Timor, has its "shore fronted by a reef, steep too on the outer
side, over which small proahs can go at the time of high water;" coloured
red.--TIMOR; most of the points, and some considerable spaces of the
northern shore, are seen in Freycinet's chart to be fringed by coral-reefs;
and mention is made of them in the accompanying "Hydrog. Memoir;" coloured
red.--SAVU, S.E. of Timor, appears in Flinders' chart to be fringed; but I
have not coloured it, as I do not know that the reefs are of coral.--
SANDALWOOD Island has, according to Horsburgh (volume ii., page 607), a
reef on its southern shore, four miles distant from the land; as the
neighbouring sea is deep, and generally bold, this probably is a barrier-
reef, but I have not ventured to colour it.

N.W. COAST OF AUSTRALIA.

It appears, in Captain King's Sailing Directions ("Narrative of Survey,"
volume ii, pages 325-369), that there are many extensive coral-reefs
skirting, often at considerable distances, the N.W. shores, and
encompassing the small adjoining islets.  Deep water, in no instance, is
represented in the charts between these reefs and the land; and, therefore,
they probably belong to the fringing class.  But as they extend far into
the sea, which is generally shallow, even in places where the land seems to
be somewhat precipitous; I have not coloured them.  Houtman's Abrolhos
(latitude 28 deg S. on west coast) have lately been surveyed by Captain
Wickham (as described in "Naut. Mag." 1841, page 511): they lie on the
edge of a steeply shelving bank, which extends about thirty miles seaward,
along the whole line of coast.  The two southern reefs, or islands, enclose
a lagoon-like space of water, varying in depth from five to fifteen
fathoms, and in one spot with twenty-three fathoms.  The greater part of
the island has been formed on their inland sides, by the accumulation of
fragments of coral; the seaward face consisting of nearly bare ledges of
rock.  Some of the specimens, brought home by Captain Wickham, contained
fragments of marine shells, but others did not; and these closely resembled
a formation at King George's Sound, principally due to the action of the
wind on calcareous dust, which I shall describe in a forthcoming part.
From the extreme irregularity of these reefs with their lagoons, and from
their position on a bank, the usual depth of which is only thirty fathoms,
I have not ventured to class them with atolls, and hence have left them
uncoloured.--ROWLEY SHOALS.  These lie some way from the N.W. coast of
Australia: according to Captain King ("Narrative of Survey," volume i.,
page 60), they are of coral-formation.  They rise abruptly from the sea,
and Captain King had no bottom with 170 fathoms close to them.  Three of
them are crescent-shaped; they are mentioned by Mr. Lyell, on the authority
of Captain King, with reference to the direction of their open sides.  "A
third oval reef of the same group is entirely submerged" ("Principles of
Geology," book iii. chapter xviii.); coloured blue.--SCOTT'S REEFS, lying
north of Rowley Shoals, are briefly described by Captain Wickham ("Naut.
Mag." 1841, page 440): they appear to be of great size, of a circular
form, and "with smooth water within, forming probably a lagoon of great
extent."  There is a break on the western side, where there probably is an
entrance: the water is very deep off these reefs; coloured blue.

Proceeding westward along the great volcanic chain of the East Indian
Archipelago, SOLOR STRAIT is represented in a chart published by Dalrymple
from a Dutch MS., as fringed; as are parts of FLORES, of ADENARA, and of
SOLOR.  Horsburgh speaks of coral growing on these shores; and therefore I
have no doubt that the reefs are of coral, and accordingly have coloured
them red.  We hear from Horsburgh (volume ii., page 602) that a coral-flat
bounds the shores of SAPY Bay.  From the same authority it appears (page
610) that reefs fringe the island of TIMOR-YOUNG, on the N. shore of
Sumbawa; and, likewise (page 600), that BALLY town in LOMBOCK, is fronted
by a reef, stretching along the shore at a distance of a hundred fathoms,
with channels through it for boats; these places, therefore, have been
coloured red.--BALLY Island.  In a Dutch MS. chart on a large scale of
Java, which was brought from that island by Dr. Horsfield, who had the
kindness to show it me at the India House, its western, northern, and
southern shores appear very regularly fringed by a reef (see also
Horsburgh, volume ii., page 593); and as coral is found abundantly there, I
have not the least doubt that the reef is of coral, and therefore have
coloured it red.

JAVA.

My information regarding the reefs of this great island is derived from the
chart just mentioned.  The greater part of MADUARA is represented in it as
regularly fringed, and likewise portions of the coast of Java immediately
south of it.  Dr. Horsfield informs me that coral is very abundant near
SOURABAYA.  The islets and parts of the N. coast of Java, west of POINT
BUANG, or JAPARA, are fringed by reefs, said to be of coral.  LUBECK, or
BAVIAN Islands, lying at some distance from the shore of Java, are
regularly fringed by coral-reefs.  CARIMON JAVA appears equally so, though
it is not directly said that the reefs are of coral; there is a depth
between thirty and forty fathoms round these islands.  Parts of the shores
of SUNDA STRAIT, where the water is from forty to eighty fathoms deep, and
the islets near BATAVIA appear in several charts to be fringed.  In the
Dutch chart the southern shore, in the narrowest part of the island, is in
two places fringed by reefs of coral.  West of SEGORROWODEE Bay, and the
extreme S.E. and E. portions are likewise fringed by coral-reefs; all the
above-mentioned places coloured red.

MACASSAR STRAIT.

The EAST COAST OF Borneo appears, in most parts, free from reefs, and where
they occur, as on the east coast of PAMAROONG, the sea is very shallow;
hence no part is coloured.  In MACASSAR Strait itself, in about latitude 2
deg S., there are many small islands with coral-shoals projecting far from
them.  There are also (old charts by Dalrymple) numerous little flats of
coral, not rising to the surface of the water, and shelving suddenly from
five fathoms to no bottom with fifty fathoms; they do not appear to have a
lagoon-like structure.  There are similar coral-shoals a little farther
south; and in latitude 4 deg 55' there are two, which are engraved from
modern surveys, in a manner which might represent an annular reef with deep
water inside: Captain Moresby, however, who was formerly in this sea,
doubts this fact, so that I have left them uncoloured: at the same time I
may remark, that these two shoals make a nearer approach to the atoll-like
structure than any other within the E. Indian Archipelago.  Southward of
these shoals there are other low islands and irregular coral-reefs; and in
the space of sea, north of the great volcanic chain, from Timor to Java, we
have also other islands, such as the POSTILLIONS, KALATOA, TOKAN-BESSEES,
etc., which are chiefly low, and are surrounded by very irregular and
distant reefs.  From the imperfect charts I have seen, I have not been able
to decide whether they belong to the atoll or barrier-classes, or whether
they merely fringe submarine banks, and gently sloping land.  In the Bay of
BONIN, between the two southern arms of Celebes, there are numerous coral-
reefs; but none of them seem to have an atoll-like structure.  I have,
therefore, not coloured any of the islands in this part of the sea; I think
it, however, exceedingly probable that some of them ought to be blue.  I
may add that there is a harbour on the S.E. coast of BOUTON which,
according to an old chart, is formed by a reef, parallel to the shore, with
deep water within; and in the "Voyage of the 'Coquille'," some neighbouring
islands are represented with reefs a good way distant, but I do not know
whether with deep water within.  I have not thought the evidence sufficient
to permit me to colour them.

SUMATRA.

Commencing with the west coast and outlying islands, ENGANO Island is
represented in the published chart as surrounded by a narrow reef, and
Napier, in his "Sailing Directions," speaks of the reef being of coral
(also Horsburgh, volume ii., page 115); coloured red.--RAT Island (3 deg
51' S.) is surrounded by reefs of coral, partly dry at low water,
(Horsburgh, volume ii., page 96).--TRIESTE Island (4 deg 2' S.).  The shore
is represented in a chart which I saw at the India House, as fringed in
such a manner, that I feel sure the fringe consists of coral; but as the
island is so low, that the sea sometimes flows quite over it (Dampier,
"Voyage," volume i., page 474), I have not coloured it.--PULO DOOA
(latitude 3 deg).  In an old chart it is said there are chasms in the reefs
round the island, admitting boats to the watering-place, and that the
southern islet consists of a mass of sand and coral.--PULO PISANG;
Horsburgh (volume ii., page 86) says that the rocky coral-bank, which
stretches about forty yards from the shore, is steep to all round: in a
chart, also, which I have seen, the island is represented as regularly
fringed.--PULO MINTAO is lined with reefs on its west side (Horsburgh,
volume ii., page 107).--PULO BANIAK; the same authority (volume ii., page
105), speaking of a part, says it is faced with coral-rocks.--MINGUIN (3
deg 36' N.).  A coral-reef fronts this place, and projects into the sea
nearly a quarter of a mile ("Notices of the Indian Arch." published at
Singapore, page 105).--PULO BRASSA (5 deg 46' N.).  A reef surrounds it at
a cable's length (Horsburgh, volume ii., page 60).  I have coloured all the
above-specified points red.  I may here add, that both Horsburgh and Mr.
Moor (in the "Notices" just alluded to) frequently speak of the numerous
reefs and banks of coral on the west coast of Sumatra; but these nowhere
have the structure of a barrier-reef, and Marsden ("History of Sumatra")
states, that where the coast is flat, the fringing-reefs extend furthest
from it.  The northern and southern points, and the greater part of the
east coast, are low, and faced with mud banks, and therefore without coral.

NICOBAR ISLANDS.

The chart represents the islands of this group as fringed by reefs.  With
regard to GREAT NICOBAR, Captain Moresby informs me, that it is fringed by
reefs of coral, extending between two and three hundred yards from the
shore.  The NORTHERN NICOBARS appear so regularly fringed in the published
charts, that I have no doubt the reefs are of coral.  This group,
therefore, is coloured red.

ANDAMAN ISLANDS.

From an examination of the MS. chart, on a large scale, of this island, by
Captain Arch. Blair, in the Admiralty, several portions of the coast appear
fringed; and as Horsburgh speaks of coral-reefs being numerous in the
vicinity of these islands, I should have coloured them red, had not some
expressions in a paper in the "Asiatic Researches" (volume iv., page 402)
led me to doubt the existence of reefs; uncoloured.

The coast of MALACCA, TENASSERIM and the coasts northward, appear in the
greater part to be low and muddy: where reefs occur, as in parts of
MALACCA STRAITS, and near SINGAPORE, they are of the fringing kind; but the
water is so shoal, that I have not coloured them.  In the sea, however,
between Malacca and the west coast of Borneo, where there is a greater
depth from forty to fifty fathoms, I have coloured red some of the groups,
which are regularly fringed.  The northern NATUNAS and the ANAMBAS Islands
are represented in the charts on a large scale, published in the "Atlas of
the Voyage of the 'Favourite'," as fringed by reefs of coral, with very
shoal water within them.--TUMBELAN and BUNOA Islands (1 deg N.) are
represented in the English charts as surrounded by a very regular fringe.--
ST. BARBES (0 deg 15' N.) is said by Horsburgh (volume ii., page 279) to be
fronted by a reef, over which boats can land only at high water.--The shore
of BORNEO at TUNJONG APEE is also fronted by a reef, extending not far from
the land (Horsburgh, volume ii., page 468).  These places I have coloured
red; although with some hesitation, as the water is shallow.  I might
perhaps have added PULO LEAT, in Gaspar Strait, LUCEPARA, and CARIMATA; but
as the sea is confined and shallow, and the reefs not very regular, I have
left them uncoloured.

The water shoals gradually towards the whole west coast of BORNEO: I
cannot make out that it has any reefs of coral.  The islands, however, off
the northern extremity, and near the S.W. end of PALAWAN, are fringed by
very distant coral-reefs; thus the reefs in the case of BALABAC are no less
than five miles from the land; but the sea, in the whole of this district,
is so shallow, that the reefs might be expected to extend very far from the
land.  I have not, therefore, thought myself authorised to colour them.
The N.E. point of Borneo, where the water is very shoal, is connected with
Magindanao by a chain of islands called the SOOLOO ARCHIPELAGO, about which
I have been able to obtain very little information; PANGOOTARAN, although
ten miles long, entirely consists of a bed of coral-rock ("Notices of E.
Indian Arch." page 58): I believe from Horsburgh that the island is low;
not coloured.--TAHOW BANK, in some old charts, appears like a submerged
atoll; not coloured.  Forrest ("Voyage," page 21) states that one of the
islands near Sooloo is surrounded by coral-rocks; but there is no distant
reef.  Near the S. end of BASSELAN, some of the islets in the chart
accompanying Forrest's "Voyage," appear fringed with reefs; hence I have
coloured, though unwillingly, parts of the Sooloo group red.  The sea
between Sooloo and Palawan, near the shoal coast of Borneo, is interspersed
with irregular reefs and shoal patches; not coloured: but in the northern
part of this sea, there are two low islets, CAGAYANES and CAVILLI,
surrounded by extensive coral-reefs; the breakers round the latter
(Horsburgh, volume ii., page 513) extend five or six miles from a sandbank,
which forms the only dry part; these breakers are steep to outside; there
appears to be an opening through them on one side, with four or five
fathoms within: from this description, I strongly suspect that Cavilli
ought to be considered an atoll; but, as I have not seen any chart of it,
on even a moderately large scale, I have not coloured it.  The islets off
the northern end of PALAWAN, are in the same case as those off the southern
end, namely they are fringed by reefs, some way distant from the shore, but
the water is exceedingly shallow; uncoloured.  The western shore of Palawan
will be treated of under the head of China Sea.

PHILIPPINE ARCHIPELAGO.

A chart on a large scale of APPOO SHOAL, which lies near the S.E. coast of
Mindoro, has been executed by Captain D. Ross: it appears atoll-formed,
but with rather an irregular outline; its diameter is about ten miles;
there are two well-defined passages leading into the interior lagoon, which
appears open; close outside the reef all round, there is no bottom with
seventy fathoms; coloured blue.--MINDORO: the N.W. coast is represented in
several charts, as fringed by a reef, and LUBAN Island is said, by
Horsburgh (volume ii., page 436), to be "lined by a reef."--LUZON: Mr.
Cuming, who has lately investigated with so much success the Natural
History of the Philippines, informs me, that about three miles of the shore
north of Point St. Jago, is fringed by a reef; as are (Horsburgh, volume
ii., page 437) the Three Friars off Silanguin Bay.  Between Point Capones
and Playa Honda, the coast is "lined by a coral-reef, stretching out nearly
a mile in some places," (Horsburgh); and Mr. Cuming visited some fringing-
reefs on parts of this coast, namely, near Puebla, Iba, and Mansinglor.  In
the neighbourhood of Solon-solon Bay, the shore is lined (Horsburgh ii.,
page 439) by coral-reefs, stretching out a great way: there are also reefs
about the islets off Solamague; and as I am informed by Mr. Cuming, near
St. Catalina, and a little north of it.  The same gentleman informs me
there are reefs on the S.E. point of this island in front of Samar,
extending from Malalabon to Bulusan.  These appear to be the principal
fringing-reefs on the coasts of Luzon; and they have all been coloured red.
Mr. Cuming informs me that none of them have deep water within; although it
appears from Horsburgh that some few extend to a considerable distance from
the shore.  Within the Philippine Archipelago, the shores of the islands do
not appear to be commonly fringed, with the exception of the S. shore of
MASBATE, and nearly the whole of BOHOL; which are both coloured red.  On
the S. shore of MAGINDANAO, Bunwoot Island is surrounded (according to
Forrest, "Voyage," page 253), by a coral-reef, which in the chart appears
one of the fringing class.  With respect to the eastern coasts of the whole
Archipelago, I have not been able to obtain any account.

BABUYAN ISLANDS.

Horsburgh says (volume ii., page 442), coral-reefs line the shores of the
harbour in Fuga; and the charts show there are other reefs about these
islands.  Camiguin has its shore in parts lined by coral-rock (Horsburgh,
page 443); about a mile off shore there is between thirty and thirty-five
fathoms.  The plan of Port San Pio Quinto shows that its shores are fringed
with coral; coloured red.--BASHEE Islands: Horsburgh, speaking of the
southern part of the group (volume ii., page 445) says the shores of both
islands are fortified by a reef, and through some of the gaps in it, the
natives can pass in their boats in fine weather; the bottom near the land
is coral-rock.  From the published charts, it is evident that several of
these islands are most regularly fringed; coloured red.  The northern
islands are left uncoloured, as I have been unable to find any account of
them.--FORMOSA.  The shores, especially the western one, seem chiefly
composed of mud and sand, and I cannot make out that they are anywhere
lined by reefs; except in a harbour (Horsburgh, volume ii., page 449) at
the extreme northern point: hence, of course, the whole of this island is
left uncoloured.  The small adjoining islands are in the same case.--
PATCHOW, or MADJIKO-SIMA GROUPS.  PATCHUSON has been described by Captain
Broughton ("Voy. to the N. Pacific," page 191); he says, the boats, with
some difficulty, found a passage through the coral-reefs, which extend
along the coast, nearly half a mile off it.  The boats were well sheltered
within the reef; but it does not appear that the water is deep there.
Outside the reef the depth is very irregular, varying from five to fifty
fathoms; the form of the land is not very abrupt; coloured red.--TAYPIN-
SAN; from the description given (page 195) by the same author, it appears
that a very irregular reef extends, to the distance of several miles, from
the southern island; but whether it encircles a space of deep water is not
evident; nor, indeed, whether these outlying reefs are connected with those
more immediately adjoining the land; left uncoloured.  I may here just add
that the shore of KUMI (lying west of Patchow), has a narrow reef attached
to it in the plan of it, in La Peyrouse's "Atlas;" but it does not appear
in the account of the voyage that it is of coral; uncoloured.--LOO CHOO.
The greater part of the coast of this moderately hilly island, is skirted
by reefs, which do not extend far from the shore, and which do not leave a
channel of deep water within them, as may be seen in the charts
accompanying Captain B. Hall's voyage to Loo Choo (see also remarks in
Appendix, pages xxi. and xxv.).  There are, however, some ports with deep
water, formed by reefs in front of valleys, in the same manner as happens
at Mauritius.  Captain Beechey, in a letter to me, compares these reefs
with those encircling the Society Islands; but there appears to me a marked
difference between them, in the less distance at which the Loo Choo reefs
lie from the land with relation to the probable submarine inclination, and
in the absence of an interior deep water-moat or channel, parallel to the
land.  Hence, I have classed these reefs with fringing-reefs, and coloured
them red.--PESCADORES (west of Formosa).  Dampier (volume i., page 416),
has compared the appearance of the land to the southern parts of England.
The islands are interlaced with coral-reefs; but as the water is very
shoal, and as spits of sand and gravel (Horsburgh, volume ii., page 450)
extend far out from them, it is impossible to draw any inferences regarding
the nature of the reefs.

CHINA SEA.--Proceeding from north to south, we first meet the PRATAS SHOAL
(latitude 20 deg N.) which, according to Horsburgh (volume ii., page 335),
is composed of coral, is of a circular form, and has a low islet on it.
The reef is on a level with the water's edge, and when the sea runs high,
there are breakers mostly all round, "but the water within seems pretty
deep in some places; although steep-to in most parts outside, there appear
to be several parts where a ship might find anchorage outside the
breakers;" coloured blue.--The PARACELLS have been accurately surveyed by
Captain D. Ross, and charts on a large scale published: but few low islets
have been formed on these shoals, and this seems to be a general
circumstance in the China Sea; the sea close outside the reefs is very
deep; several of them have a lagoon-like structure; or separate islets
(PRATTLE, ROBERT, DRUMMOND, etc.) are so arranged round a moderately
shallow space, as to appear as if they had once formed one large atoll.--
BOMBAY SHOAL (one of the Paracells) has the form of an annular reef, and is
"apparently deep within;" it seems to have an entrance (Horsburgh, volume
ii., page 332) on its west side; it is very steep outside.--DISCOVERY
SHOAL, also is of an oval form, with a lagoon-like space within, and three
openings leading into it, in which there is a depth from two to twenty
fathoms.  Outside, at the distance (Horsburgh, volume ii., page 333) of
only twenty yards from the reef, soundings could not be obtained.  The
Paracells are coloured blue.--MACCLESFIELD BANK: this is a coral-bank of
great size, lying east of the Paracells; some parts of the bank are level,
with a sandy bottom, but, generally, the depth is very irregular.  It is
intersected by deep cuts or channels.  I am not able to perceive in the
published charts (its limits, however, are not very accurately known)
whether the central part is deeper, which I suspect is the case, as in the
Great Chagos Bank, in the Indian Ocean; not coloured.--SCARBOROUGH SHOAL:
this coral-shoal is engraved with a double row of crosses, forming a
circle, as if there was deep water within the reef: close outside there
was no bottom, with a hundred fathoms; coloured blue.--The sea off the west
coast of Palawan and the northern part of Borneo is strewed with shoals:
SWALLOW SHOAL, according to Horsburgh (volume ii., page 431) "is formed,
LIKE MOST of the shoals hereabouts, of a belt of coral-rocks, "with a basin
of deep water within."--HALF-MOON SHOAL has a similar structure; Captain D.
Ross describes it, as a narrow belt of coral-rock, "with a basin of deep
water in the centre," and deep sea close outside.--BOMBAY SHOAL appears
(Horsburgh, volume ii., page 432) "to be a basin of smooth water surrounded
by breakers."  These three shoals I have coloured blue.--The PARAQUAS
SHOALS are of a circular form, with deep gaps running through them; not
coloured.--A bank gradually shoaling to the depth of thirty fathoms,
extends to a distance of about twenty miles from the northern part of
BORNEO, and to thirty miles from the northern part of PALAWAN.  Near the
land this bank appears tolerably free from danger, but a little further out
it is thickly studded with coral-shoals, which do not generally rise quite
to the surface; some of them are very steep-to, and others have a fringe of
shoal-water round them.  I should have thought that these shoals had level
surfaces, had it not been for the statement made by Horsburgh "that most of
the shoals hereabouts are formed of a belt of coral."  But, perhaps that
expression was more particularly applied to the shoals further in the
offing.  If these reefs of coral have a lagoon-like structure, they should
have been coloured blue, and they would have formed an imperfect barrier in
front of Palawan and the northern part of Borneo.  But, as the water is not
very deep, these reefs may have grown up from inequalities on the bank: I
have not coloured them.--The coast of CHINA, TONQUIN, and COCHIN-CHINA,
forming the western boundary of the China Sea, appear to be without reefs:
with regard to the two last-mentioned coasts, I speak after examining the
charts on a large scale in the "Atlas of the Voyage of the 'Favourite'."

INDIAN OCEAN.

SOUTH KEELING atoll has been specially described.  Nine miles north of it
lies North Keeling, a very small atoll, surveyed by the "Beagle," the
lagoon of which is dry at low water.--CHRISTMAS Island, lying to the east,
is a high island, without, as I have been informed by a person who passed
it, any reefs at all.--CEYLON: a space about eighty miles in length of the
south-western and southern shores of these islands has been described by
Mr. Twynam ("Naut. Mag." 1836, pages 365 and 518); parts of this space
appear to be very regularly fringed by coral-reefs, which extend from a
quarter to half a mile from the shore.  These reefs are in places breached,
and afford safe anchorage for the small trading craft.  Outside, the sea
gradually deepens; there is forty fathoms about six miles off shore: this
part I have coloured red.  In the published charts of Ceylon there appear
to be fringing-reefs in several parts of the south-eastern shores, which I
have also coloured red.--At Venloos Bay the shore is likewise fringed.
North of Trincomalee there are also reefs of the same kind.  The sea off
the northern part of Ceylon is exceedingly shallow; and therefore I have
not coloured the reefs which fringe portions of its shores, and the
adjoining islets, as well as the Indian promontory of MADURA.

CHAGOS, MALDIVA, AND LACCADIVE ARCHIPELAGOES.

These three great groups which have already been often noticed, are now
well-known from the admirable surveys of Captain Moresby and Lieutenant
Powell.  The published charts, which are worthy of the most attentive
examination, at once show that the CHAGOS and MALDIVA groups are entirely
formed of great atolls, or lagoon-formed reefs, surmounted by islets.  In
the LACCADIVE group, this structure is less evident; the islets are low,
not exceeding the usual height of coral-formations (see Lieutenant Wood's
account, "Geographical Journal", volume vi., page 29), and most of the
reefs are circular, as may be seen in the published charts; and within
several of them, as I am informed by Captain Moresby, there is deepish
water; these, therefore, have been coloured blue.  Directly north, and
almost forming part of this group, there is a long, narrow, slightly curved
bank, rising out of the depths of the ocean, composed of sand, shells, and
decayed coral, with from twenty-three to thirty fathoms on it.  I have no
doubt that it has had the same origin with the other Laccadive banks; but
as it does not deepen towards the centre I have not coloured it.  I might
have referred to other authorities regarding these three archipelagoes; but
after the publication of the charts by Captain Moresby, to whose personal
kindness in giving me much information I am exceedingly indebted, it would
have been superfluous.

SAHIA DE MALHA bank consists of a series of narrow banks, with from eight
to sixteen fathoms on them; they are arranged in a semicircular manner,
round a space about forty fathoms deep, which slopes on the S.E. quarter to
unfathomable depths; they are steep-to on both sides, but more especially
on the ocean-side.  Hence this bank closely resembles in structure, and I
may add from Captain Moresby's information in composition, the Pitt's Bank
in the Chagos group; and the Pitt's Bank, must, after what has been shown
of the Great Chagos Bank, be considered as a sunken, half-destroyed atoll;
hence coloured blue.--CARGADOS CARAJOS BANK.  Its southern portion consists
of a large, curved, coral-shoal, with some low islets on its eastern edge,
and likewise some on the western side, between which there is a depth of
about twelve fathoms.  Northward, a great bank extends. I cannot (probably
owing to the want of perfect charts) refer this reef and bank to any
class;--therefore not coloured.--ILE DE SABLE is a little island, lying
west of C. Carajos, only some toises in height ("Voyage of the
'Favourite'," volume i., page 130); it is surrounded by reefs; but its
structure is unintelligible to me.  There are some small banks north of it,
of which I can find no clear account.--MAURITIUS. The reefs round this
island have been described in the chapter on fringing-reefs; coloured red.
--RODRIGUEZ.  The coral-reefs here are exceedingly extensive; in one part
they project even five miles from the shore.  As far as I can make out,
there is no deep-water moat within them; and the sea outside does not
deepen very suddenly.  The outline, however, of the land appears to be
("Life of Sir J. Makintosh," volume ii., page 165) hilly and rugged.  I am
unable to decide whether these reefs belong to the barrier class; as seems
probable from their great extension, or to the fringing class; uncoloured.
--BOURBON.  The greater part of the shores of this island are without
reefs; but Captain Carmichael (Hooker's "Bot. Misc.") states that a
portion, fifteen miles in length, on the S.E. side, is imperfectly fringed
with coral reefs: I have not thought this sufficient to colour the island.

SEYCHELLES.

The rocky islands of primary formation, composing this group, rise from a
very extensive and tolerably level bank, having a depth between twenty and
forty fathoms.  In Captain Owen's chart, and in that in the "Atlas of the
Voyage of the 'Favourite'," it appears that the east side of MAHE and the
adjoining islands of ST. ANNE and CERF, are regularly fringed by coral-reefs.
A portion of the S.E. part of CURIEUSE Island, the N., and part of
the S.W. shore of PRASLIN Island, and the whole west side of DIGUE Island,
appear fringed.  From a MS. account of these islands by Captain F. Moresby,
in the Admiralty, it appears that SILHOUETTE is also fringed; he states
that all these islands are formed of granite and quartz, that they rise
abruptly from the sea, and that "coral-reefs have grown round them, and
project for some distance."  Dr. Allan, of Forres, who visited these
islands, informs me that there is no deep water between the reefs and the
shore.  The above specified points have been coloured red.  AMIRANTES
Islands: The small islands of this neighbouring group, according to the
MS. account of them by Captain F. Moresby, are situated on an extensive
bank; they consist of the debris of corals and shells; are only about
twenty feet in height, and are environed by reefs, some attached to the
shore, and some rather distant from it.--I have taken great pains to
procure plans and information regarding the several islands lying between
S.E. and S.W. of the Amirantes, and the Seychelles; relying chiefly on
Captain F. Moresby and Dr. Allan, it appears that the greater number,
namely--PLATTE, ALPHONSE, COETIVI, GALEGA, PROVIDENCE, ST. PIERRE, ASTOVA,
ASSOMPTION, and GLORIOSO, are low, formed of sand or coral-rock, and
irregularly shaped; they are situated on very extensive banks, and are
connected with great coral-reefs.  Galega is said by Dr. Allan, to be
rather higher than the other islands; and St. Pierre is described by
Captain F. Moresby, as being cavernous throughout, and as not consisting of
either limestone or granite.  These islands, as well as the Amirantes,
certainly are not atoll-formed, and they differ as a group from every other
group with which I am acquainted; I have not coloured them; but probably
the reefs belong to the fringing class.  Their formation is attributed,
both by Dr. Allan and Captain F. Moresby, to the action of the currents,
here exceedingly violent, on banks, which no doubt have had an independent
geological origin.  They resemble in many respects some islands and banks
in the West Indies, which owe their origin to a similar agency, in
conjunction with an elevation of the entire area.  In close vicinity to the
several islands, there are three others of an apparently different nature:
first, JUAN DE NOVA, which appears from some plans and accounts to be an
atoll; but from others does not appear to be so; not coloured.  Secondly
COSMOLEDO; "this group consists of a ring of coral, ten leagues in
circumference, and a quarter of a mile broad in some places, enclosing a
magnificent lagoon, into which there did not appear a single opening"
(Horsburgh, volume i., page 151); coloured blue.  Thirdly, ALDABRA; it
consists of three islets, about twenty-five feet in height, with red cliffs
(Horsburgh, volume i., page 176) surrounding a very shallow basin or
lagoon.  The sea is profoundly deep close to the shore.  Viewing this
island in a chart, it would be thought an atoll; but the foregoing
description shows that there is something different in its nature; Dr.
Allan also states that it is cavernous, and that the coral-rock has a
vitrified appearance.  Is it an upheaved atoll, or the crater of a
volcano?--uncoloured.

COMORO GROUP.

MAYOTTA, according to Horsburgh (volume i., page 216, 4th edition), is
completely surrounded by a reef, which runs at the distance of three, four,
and in some places even five miles from the land; in an old chart,
published by Dalrymple, a depth in many places of thirty-six and thirty-eight
fathoms is laid down within the reef.  In the same chart, the space
of open water within the reef in some parts is even more than three miles
wide: the land is bold and peaked; this island, therefore, is encircled by
a well-characterised barrier-reef, and is coloured pale blue.--JOHANNA;
Horsburgh says (volume I. page 217) this island from the N.W. to the S.W.
point, is bounded by a reef, at the distance of two miles from the shore;
in some parts, however, the reef must be attached, since Lieutenant Boteler
("Narr." volume i., page 161) describes a passage through it, within which
there is room only for a few boats.  Its height, as I am informed by Dr.
Allan, is about 3,500 feet; it is very precipitous, and is composed of
granite, greenstone, and quartz; coloured blue.--MOHILLA; on the S. side of
this island there is anchorage, in from thirty to forty-five fathoms,
between a reef and the shore (Horsburgh, volume i., page 214); in Captain
Owen's chart of Madagascar, this island is represented as encircled;
coloured blue.--GREAT COMORO Island is, as I am informed by Dr. Allan,
about 8,000 feet high, and apparently volcanic; it is not regularly
encircled; but reefs of various shapes and dimensions, jut out from every
headland on the W., S., and S.E. coasts, inside of which reefs there are
channels, often parallel with the shore, with deep water.  On the
north-western coasts the reefs appear attached to the shores.  The land near
the coast is in some places bold, but generally speaking it is flat;
Horsburgh says (volume i., page 214) the water is profoundly deep close to
the SHORE, from which expression I presume some parts are without reefs.
From this description I apprehend the reef belongs to the barrier class;
but I have not coloured it, as most of the charts which I have seen,
represent the reefs round it as very much less extensive than round the
other islands in the group.

MADAGASCAR.

My information is chiefly derived from the published charts by Captain
Owen, and the accounts given by him and by Lieutenant Boteler.  Commencing
at the S.W. extremity of the island; towards the northern part of the STAR
BANK (in latitude 25 deg S.) the coast for ten miles is fringed by a reef;
coloured red.  The shore immediately S. of ST. AUGUSTINE'S BAY appears
fringed; but TULLEAR Harbour, directly N. of it, is formed by a narrow reef
ten miles long, extending parallel to the shore, with from four to ten
fathoms within it.  If this reef had been more extensive, it must have been
classed as a barrier-reef; but as the line of coast falls inwards here, a
submarine bank perhaps extends parallel to the shore, which has offered a
foundation for the growth of the coral; I have left this part uncoloured.
From latitude 22 deg 16' to 21 deg 37', the shore is fringed by coral-reefs
(see Lieutenant Boteler's "Narrative," volume ii., page 106), less than a
mile in width, and with shallow water within.  There are outlying
coral-shoals  in several parts of the offing, with about ten fathoms between
them and the shore, and the depth of the sea one mile and a half seaward, is
about thirty fathoms.  The part above specified is engraved on a large
scale; and as in the charts on rather a smaller scale the same fringe of
reef extends as far as latitude 33 deg 15'; I have coloured the whole of
this part of the coast red.  The islands of JUAN DE NOVA (in latitude 17
deg S.) appear in the charts on a large scale to be fringed, but I have not
been able to ascertain whether the reefs are of coral; uncoloured.  The
main part of the west coast appears to be low, with outlying sandbanks,
which, Lieutenant Boteler (volume ii., page 106) says, "are faced on the
edge of deep water by a line of sharp-pointed coral-rocks."  Nevertheless I
have not coloured this part, as I cannot make out by the charts that the
coast itself is fringed.  The headlands of NARRENDA and PASSANDAVA Bays (14
deg 40') and the islands in front of RADAMA HARBOUR are represented in the
plans as regularly fringed, and have accordingly been coloured red.  With
respect to the EAST COAST OF MADAGASCAR, Dr. Allan informs me in a letter,
that the whole line of coast, from TAMATAVE, in 18 deg 12', to C. AMBER, at
the extreme northern point of the island, is bordered by coral-reefs.  The
land is low, uneven, and gradually rising from the coast.  From Captain
Owen's charts, also, the existence of these reefs, which evidently belong
to the fringing class, on some parts, namely N. of BRITISH SOUND, and near
NGONCY, of the above line of coast might have been inferred.  Lieutenant
Boteler (volume i., page 155) speaks of "the reef surrounding the island of
ST. MARY'S at a small distance from the shore."  In a previous chapter I
have described, from the information of Dr. Allan, the manner in which the
reefs extend in N.E. lines from the headlands on this coast, thus sometimes
forming rather deep channels within them, this seems caused by the action
of the currents, and the reefs spring up from the submarine prolongations
of the sandy headlands.  The above specified portion of the coast is
coloured red.  The remaining S.E. portions do not appear in any published
chart to possess reefs of any kind; and the Rev. W. Ellis, whose means of
information regarding this side of Madagascar have been extensive, informs
me he believes there are none.

EAST COAST OF AFRICA.

Proceeding from the northern part, the coast appears, for a considerable
space, without reefs.  My information, I may here observe, is derived from
the survey by Captain Owen, together with his narrative; and that by
Lieutenant Boteler.  At MUKDEESHA (10 deg 1' N.) there is a coral-reef
extending four or five miles along the shore (Owen's "Narr." volume i, page
357) which in the chart lies at the distance of a quarter of a mile from
the shore, and has within it from six to ten feet water: this then is a
fringing-reef, and is coloured red.  From JUBA, a little S. of the equator,
to LAMOO (in 2 deg 20' S.) "the coast and islands are formed of madrepore"
(Owen's "Narrative," volume i., page 363).  The chart of this part
(entitled DUNDAS Islands), presents an extraordinary appearance; the coast
of the mainland is quite straight and it is fronted at the average distance
of two miles, by exceedingly narrow, straight islets, fringed with reefs.
Within the chain of islets, there are extensive tidal flats and muddy bays,
into which many rivers enter; the depths of these spaces varies from one to
four fathoms--the latter depth not being common, and about twelve feet the
average.  Outside the chain of islets, the sea, at the distance of a mile,
varies in depth from eight to fifteen fathoms.  Lieutenant Boteler ("Narr."
volume i., page 369) describes the muddy bay of PATTA, which seems to
resemble other parts of this coast, as fronted by small, narrow, level
islets formed of decomposing coral, the margin of which is seldom of
greater height than twelve feet, overhanging the rocky surface from which
the islets rise.  Knowing that the islets are formed of coral, it is, I
think, scarcely possible to view the coast, and not at once conclude that
we here see a fringing-reef, which has been upraised a few feet: the
unusual depth of from two to four fathoms within some of these islets, is
probably due to muddy rivers having prevented the growth of coral near the
shore.  There is, however, one difficulty on this view, namely, that before
the elevation took place, which converted the reef into a chain of islets,
the water must apparently have been still deeper; on the other hand it may
be supposed that the formation of a nearly perfect barrier in front, of so
large an extent of coast, would cause the currents (especially in front of
the rivers), to deepen their muddy beds.  When describing in the chapter on
fringing-reefs, those of Mauritius, I have given my reasons for believing
that the shoal spaces within reefs of this kind, must, in many instances,
have been deepened.  However this may be, as several parts of this line of
coast are undoubtedly fringed by living reefs, I have coloured it red.--
MALEENDA (3 deg 20' S.).  In the plan of the harbour, the south headland
appears fringed; and in Owen's chart on a larger scale, the reefs are seen
to extend nearly thirty miles southward; coloured red.--MOMBAS (4 deg 5'
S.).  The island which forms the harbour, "is surrounded by cliffs of
madrepore, capable of being rendered almost impregnable" (Owen's "Narr."
volume i., page 412).  The shore of the mainland N. and S. of the harbour,
is most regularly fringed by a coral-reef at a distance from half a mile to
one mile and a quarter from the land; within the reef the depth is from
nine to fifteen feet; outside the reef the depth at rather less than half a
mile is thirty fathoms.  From the charts it appears that a space about
thirty-six miles in length, is here fringed; coloured red.--PEMBA (5 deg
S.) is an island of coral-formation, level, and about two hundred feet in
height (Owen's "Narr." volume i., page 425); it is thirty-five miles long,
and is separated from the mainland by a deep sea.  The outer coast is
represented in the chart as regularly fringed; coloured red.  The mainland
in front of Pemba is likewise fringed; but there also appear to be some
outlying reefs with deep water between them and the shore.  I do not
understand their structure, either from the charts or the description,
therefore have not coloured them.--ZANZIBAR resembles Pemba in most
respects; its southern half on the western side and the neighbouring islets
are fringed; coloured red.  On the mainland, a little S. of Zanzibar, there
are some banks parallel to the coast, which I should have thought had been
formed of coral, had it not been said (Boteler's "Narr." volume ii., page
39) that they were composed of sand; not coloured.--LATHAM'S BANK is a
small island, fringed by coral-reefs; but being only ten feet high, it has
not been coloured.--MONFEEA is an island of the same character as Pemba;
its outer shore is fringed, and its southern extremity is connected with
Keelwa Point on the mainland by a chain of islands fringed by reefs;
coloured red.  The four last-mentioned islands resemble in many respects
some of the islands in the Red Sea, which will presently be described.--
KEELWA.  In a plan of the shore, a space of twenty miles N. and S. of this
place is fringed by reefs, apparently of coral: these reefs are prolonged
still further southward in Owen's general chart.  The coast in the plans of
the rivers LINDY and MONGHOW (9 deg 59' and 10 deg 7' S.) has the same
structure; coloured red.--QUERIMBA Islands (from 10 deg 40' to 13 deg S.).
A chart on a large scale is given of these islands; they are low, and of
coral-formation (Boteler's "Narr." volume ii., page 54); and generally have
extensive reefs projecting from them which are dry at low water, and which
on the outside rise abruptly from a deep sea: on their insides they are
separated from the continent by a channel, or rather a succession of bays,
with an average depth of ten fathoms.  The small headlands on the continent
also have coral-banks attached to them; and the Querimba islands and banks
are placed on the lines of prolongation of these headlands, and are
separated from them by very shallow channels.  It is evident that whatever
cause, whether the drifting of sediment or subterranean movements, produced
the headlands, likewise produced, as might have been expected, submarine
prolongations to them; and these towards their outer extremities, have
since afforded a favourable basis for the growth of coral-reefs, and
subsequently for the formation of islets.  As these reefs clearly belong to
the fringing class, the Querimba islands have been coloured red.--MONABILA
(13 deg 32' S.).  In the plan of this harbour, the headlands outside are
fringed by reefs apparently of coral; coloured red.--MOZAMBIQUE (150 deg
S.)  The outer part of the island on which the city is built, and the
neighbouring islands, are fringed by coral-reefs; coloured red.  From the
description given in Owen's "Narr." (volume i., page 162), the shore from
MOZAMBIQUE to DELAGOA BAY appears to be low and sandy; many of the shoals
and islets off this line of coast are of coral-formation; but from their
small size and lowness, it is not possible, from the charts, to know
whether they are truly fringed.  Hence this portion of coast is left
uncoloured, as are likewise those parts more northward, of which no mention
has been made in the foregoing pages from the want of information.

PERSIAN GULF.

From the charts lately published on a large scale by the East India
Company, it appears that several parts, especially the southern shores of
this gulf, are fringed by coral-reefs; but as the water is very shallow,
and as there are numerous sandbanks, which are difficult to distinguish on
the chart from reefs, I have not coloured the upper part red.  Towards the
mouth, however, where the water is rather deeper, the islands of ORMUZ and
LARRACK, appear so regularly fringed, that I have coloured them red.  There
are certainly no atolls in the Persian Gulf.  The shores of IMMAUM, and of
the promontory forming the southern headland of the Persian Gulf, seem to
be without reefs.  The whole S.W. part (except one or two small patches) of
ARABIA FELIX, and the shores of SOCOTRA appear from the charts and memoir
of Captain Haines ("Geographical Journal," 1839, page 125) to be without
any reefs.  I believe there are no extensive coral-reefs on any part of the
coasts of INDIA, except on the low promontory of MADURA (as already
mentioned) in front of Ceylon.

RED SEA.

My information is chiefly derived from the admirable charts published by
the East India Company in 1836, from personal communication with Captain
Moresby, one of the surveyors, and from the excellent memoir, "Uber die
Natur der Corallen-Banken des Rothen Meeres," by Ehrenberg.  The plains
immediately bordering the Red Sea seem chiefly to consist of a sedimentary
formation of the newer tertiary period.  The shore is, with the exception
of a few parts, fringed by coral-reefs.  The water is generally profoundly
deep close to the shore; but this fact, which has attracted the attention
of most voyagers, seems to have no necessary connection with the presence
of reefs; for Captain Moresby particularly observed to me, that, in
latitude 24 deg 10' on the eastern side, there is a piece of coast, with
very deep water close to it, without any reefs, but not differing in other
respects from the usual nature of the coast-line.  The most remarkable
feature in the Red Sea is the chain of submerged banks, reefs, and islands,
lying some way from the shore, chiefly on the eastern side; the space
within being deep enough to admit a safe navigation in small vessels.  The
banks are generally of an oval form, and some miles in width; but some of
them are very long in proportion to their width.  Captain Moresby informs
me that any one, who had not made actual plans of them, would be apt to
think that they were much more elongated than they really are.  Many of
them rise to the surface, but the greater number lie from five to thirty
fathoms beneath it, with irregular soundings on them.  They consist of sand
and living coral; coral on most of them, according to Captain Moresby,
covering the greater part of their surface.  They extend parallel to the
shore, and they are not unfrequently connected in their middle parts by
short transverse banks with the mainland.  The sea is generally profoundly
deep quite close to them, as it is near most parts of the coast of the
mainland; but this is not universally the case, for between latitude 15 deg
and 17 deg the water deepens quite gradually from the banks, both on the
eastern and western shores, towards the middle of the sea.  Islands in many
parts arise from these banks; they are low, flat-topped, and consist of the
same horizontally stratified formation with that forming the plain-like
margin of the mainland.  Some of the smaller and lower islands consist of
mere sand.  Captain Moresby informs me, that small masses of rock, the
remnants of islands, are left on many banks where there is now no dry land.
Ehrenberg also asserts that most of the islets, even the lowest, have a
flat abraded basis, composed of the same tertiary formation: he believes
that as soon as the surf wears down the protuberant parts of a bank, just
beneath the level of the sea, the surface becomes protected from further
abrasion by the growth of coral, and he thus accounts for the existence of
so many banks standing on a level with the surface of this sea.  It appears
that most of the islands are certainly decreasing in size.

The form of the banks and islands is most singular in the part just
referred to, namely, from latitude 15 deg to 17 deg, where the sea deepens
quite gradually: the DHALAC group, on the western coast, is surrounded by
an intricate archipelago of islets and shoals; the main island is very
irregularly shaped, and it includes a bay seven miles long, by four across,
in which no bottom was found with 252 feet: there is only one entrance
into this bay, half a mile wide, and with an island in front of it.  The
submerged banks on the eastern coast, within the same latitudes, round
FARSAN Island, are, likewise, penetrated by many narrow creeks of deep
water; one is twelve miles long, in the form of a hatchet, in which, close
to its broad upper end, soundings were not struck with 360 feet, and its
entrance is only half a mile wide: in another creek of the same nature,
but even with a more irregular outline, there was no bottom with 480 feet.
The island of Farsan, itself, has as singular a form as any of its
surrounding banks.  The bottom of the sea round the Dhalac and Farsan
Islands consists chiefly of sand and agglutinated fragments, but, in the
deep and narrow creeks, it consists of mud; the islands themselves consist
of thin, horizontally stratified, modern tertiary beds, containing but
little broken coral (Ruppell, "Reise in Abyssinie," Band. i., S. 247.),
their shores are fringed by living coral-reefs.

From the account given by Ruppell (Ibid., S. 245.) of the manner in which
Dhalac has been rent by fissures, the opposite sides of which have been
unequally elevated (in one instance to the amount of fifty feet), it seems
probable that its irregular form, as well as probably that of Farsan, may
have been partly caused by unequal elevations; but, considering the general
form of the banks, and of the deep-water creeks, together with the
composition of the land, I think their configuration is more probably due
in great part to strong currents having drifted sediment over an uneven
bottom: it is almost certain that their form cannot be attributed to the
growth of coral.  Whatever may have been the precise origin of the Dhalac
and Farsan Archipelagoes, the greater number of the banks on the eastern
side of the Red Sea seem to have originated through nearly similar means.
I judge of this from their similarity in configuration (in proof of which I
may instance a bank on the east coast in latitude 22 deg; and although it
is true that the northern banks generally have a less complicated outline),
and from their similarity in composition, as may be observed in their
upraised portions.  The depth within the banks northward of latitude 17
deg, is usually greater, and their outer sides shelve more abruptly
(circumstances which seem to go together) than in the Dhalac and Farsan
Archipelagoes; but this might easily have been caused by a difference in
the action of the currents during their formation: moreover, the greater
quantity of living coral, which, according to Captain Moresby, exists on
the northern banks, would tend to give them steeper margins.

From this account, brief and imperfect as it is, we can see that the great
chain of banks on the eastern coast, and on the western side in the
southern portion, differ greatly from true barrier-reefs wholly formed by
the growth of coral.  It is indeed the direct conclusion of Ehrenberg
("Uber die," etc., pages 45 and 51), that they are connected in their
origin quite secondarily with the growth of coral; and he remarks that the
islands off the coast of Norway, if worn down level with the sea, and
merely coated with living coral, would present a nearly similar appearance.
I cannot, however, avoid suspecting, from information given me by Dr.
Malcolmson and Captain Moresby, that Ehrenberg has rather under-rated the
influence of corals, in some places at least, on the formation of the
tertiary deposits of the Red Sea.

THE WEST COAST OF THE RED SEA BETWEEN LATITUDE 19 DEG AND 22 DEG.

There are, in this space, reefs, which, if I had known nothing of those in
other parts of the Red Sea, I should unhesitatingly have considered as
barrier-reefs; and, after deliberation, I have come to the same conclusion.
One of these reefs, in 20 deg 15', is twenty miles long, less than a mile
in width (but expanding at the northern end into a disc), slightly sinuous,
and extending parallel to the mainland at the distance of five miles from
it, with very deep water within; in one spot soundings were not obtained
with 205 fathoms.  Some leagues further south, there is another linear
reef, very narrow, ten miles long, with other small portions of reef, north
and south, almost connected with it; and within this line of reefs (as well
as outside) the water is profoundly deep.  There are also some small linear
and sickle-formed reefs, lying a little way out at sea.  All these reefs
are covered, as I am informed by Captain Moresby, by living corals.  Here,
then, we have all the characters of reefs of the barrier class; and in some
outlying reefs we have an approach to the structure of atolls.  The source
of my doubts about the classification of these reefs, arises from having
observed in the Dhalac and Farsan groups the narrowness and straightness of
several spits of sand and rock: one of these spits in the Dhalac group is
nearly fifteen miles long, only two broad, and it is bordered on each side
with deep water; so that, if worn down by the surf, and coated with living
corals, it would form a reef nearly similar to those within the space under
consideration.  There is, also, in this space (latitude 21 deg) a
peninsula, bordered by cliffs, with its extremity worn down to the level of
the sea, and its basis fringed with reefs: in the line of prolongation of
this peninsula, there lies the island of MACOWA (formed, according to
Captain Moresby, of the usual tertiary deposit), and some smaller islands,
large parts of which likewise appear to have been worn down, and are now
coated with living corals.  If the removal of the strata in these several
cases had been more complete, the reefs thus formed would have nearly
resembled those barrier-like ones now under discussion.  Notwithstanding
these facts, I cannot persuade myself that the many very small, isolated,
and sickle-formed reefs and others, long, nearly straight, and very narrow,
with the water unfathomably deep close round them, could possibly have been
formed by corals merely coating banks of sediment, or the abraded surfaces
of irregularly shaped islands.  I feel compelled to believe that the
foundations of these reefs have subsided, and that the corals, during their
upward growth, have given to these reefs their present forms: I may remark
that the subsidence of narrow and irregularly-shaped peninsulas and
islands, such as those existing on the coasts of the Red Sea, would afford
the requisite foundations for the reefs in question.

THE WEST COAST FROM LATITUDE 22 DEG TO 24 DEG.

This part of the coast (north of the space coloured blue on the map) is
fronted by an irregularly shelving bank, from about ten to thirty fathoms
deep; numerous little reefs, some of which have the most singular shapes,
rise from this bank.  It may be observed, respecting one of them, in
latitude 23 deg 10', that if the promontory in latitude 24 deg were worn
down to the level of the sea, and coated with corals, a very similar and
grotesquely formed reef would be produced.  Many of the reefs on this part
of the coast may thus have originated; but there are some sickle, and
almost atoll-formed reefs lying in deep water off the promontory in
latitude 24 deg, which lead me to suppose that all these reefs are more
probably allied to the barrier or atoll classes.  I have not, however,
ventured to colour this portion of coast.  ON THE WEST COAST FROM LATITUDE
19 DEG TO 17 DEG (south of space coloured blue on the map), there are many
low islets of very small dimensions, not much elongated, and rising out of
great depths at a distance from the coast; these cannot be classed either
with atolls, or barrier- or fringing-reefs.  I may here remark that the
outlying reefs on the west coast, between latitude 19 deg and 24 deg, are
the only ones in the Red Sea, which approach in structure to the true
atolls of the Indian and Pacific Oceans, but they present only imperfect
miniature likenesses of them.

EASTERN COAST.

I have felt the greatest doubt about colouring any portion of this coast,
north of the fringing-reefs round the Farsan Islands in 16 deg 10'.  There
are many small outlying coral-reefs along the whole line of coast; but as
the greater number rise from banks not very deeply submerged (the formation
of which has been shown to be only secondarily connected with the growth of
coral), their origin may be due simply to the growth of knolls of corals,
from an irregular foundation situated within a limited depth.  But between
latitude 18 deg and 20 deg, there are so many linear, elliptic, and
extremely small reefs, rising abruptly out of profound depths, that the
same reasons, which led me to colour blue a portion of the west coast, have
induced me to do the same in this part.  There exist some small outlying
reefs rising from deep water, north of latitude 20 deg (the northern limit
coloured blue), on the east coast; but as they are not very numerous and
scarcely any of them linear, I have thought it right to leave them
uncoloured.

In the SOUTHERN PARTS of the Red Sea, considerable spaces of the mainland,
and of some of the Dhalac islands, are skirted by reefs, which, as I am
informed by Captain Moresby, are of living coral, and have all the
characters of the fringing class.  As in these latitudes, there are no
outlying linear or sickle-formed reefs, rising out of unfathomable depths,
I have coloured these parts of the coast red.  On similar grounds, I have
coloured red the NORTHERN PARTS OF THE WESTERN COAST (north of latitude 24
deg 30'), and likewise the shores of the chief part of the GULF OF SUEZ.
In the GULF OF ACABA, as I am informed by Captain Moresby there are no
coral-reefs, and the water is profoundly deep.

WEST INDIES.

My information regarding the reefs of this area, is derived from various
sources, and from an examination of numerous charts; especially of those
lately executed during the survey under Captain Owen, R.N.  I lay under
particular obligation to Captain Bird Allen, R.N., one of the members of
the late survey, for many personal communications on this subject.  As in
the case of the Red Sea, it is necessary to make some preliminary remarks
on the submerged banks of the West Indies, which are in some degree
connected with coral-reefs, and cause considerable doubts in their
classification.  That large accumulations of sediment are in progress on
the West Indian shores, will be evident to any one who examines the charts
of that sea, especially of the portion north of a line joining Yucutan and
Florida.  The area of deposition seems less intimately connected with the
debouchement of the great rivers, than with the course of the sea-currents;
as is evident from the vast extension of the banks from the promontories of
Yucutan and Mosquito.

Besides the coast-banks, there are many of various dimensions which stand
quite isolated; these closely resemble each other, they lie from two or
three to twenty or thirty fathoms under water, and are composed of sand,
sometimes firmly agglutinated, with little or no coral; their surfaces are
smooth and nearly level, shelving only to the amount of a few fathoms, very
gradually all round towards their edges, where they plunge abruptly into
the unfathomable sea.  This steep inclination of their sides, which is
likewise characteristic of the coast-banks, is very remarkable: I may give
as an instance, the Misteriosa Bank, on the edges of which the soundings
change in 250 fathoms horizontal distance, from 11 to 210 fathoms; off the
northern point of the bank of Old Providence, in 200 fathoms horizontal
distance, the change is from 19 to 152 fathoms; off the Great Bahama Bank,
in 160 fathoms horizontal distance, the inclination is in many places from
10 fathoms to no bottom with 190 fathoms.  On coasts in all parts of the
world, where sediment is accumulating, something of this kind may be
observed; the banks shelve very gently far out to sea, and then terminate
abruptly.  The form and composition of the banks standing in the middle
parts of the W. Indian Sea, clearly show that their origin must be chiefly
attributed to the accumulation of sediment; and the only obvious
explanation of their isolated position is the presence of a nucleus, round
which the currents have collected fine drift matter.  Any one who will
compare the character of the bank surrounding the hilly island of Old
Providence, with those banks in its neighbourhood which stand isolated,
will scarcely doubt that they surround submerged mountains.  We are led to
the same conclusion by examining the bank called Thunder Knoll, which is
separated from the Great Mosquito Bank by a channel only seven miles wide,
and 145 fathoms deep.  There cannot be any doubt that the Mosquito Bank has
been formed by the accumulation of sediment round the promontory of the
same name; and Thunder Knoll resembles the Mosquito Bank, in the state of
its surface submerged twenty fathoms, in the inclinations of its sides, in
composition, and in every other respect.  I may observe, although the
remark is here irrelevant, that geologists should be cautious in concluding
that all the outlyers of any formation have once been connected together,
for we here see that deposits, doubtless of exactly the same nature, may be
deposited with large valley-like spaces between them.

Linear strips of coral-reefs and small knolls project from many of the
isolated, as well as coast-banks; sometimes they occur quite irregularly
placed, as on the Mosquito Bank, but more generally they form crescents on
the windward side, situated some little distance within the outer edge of
the banks:--thus on the Serranilla Bank they form an interrupted chain
which ranges between two and three miles within the windward margin:
generally they occur, as on Roncador, Courtown, and Anegada Banks, nearer
the line of deep water.  Their occurrence on the windward side is
conformable to the general rule, of the efficient kinds of corals
flourishing best where most exposed; but their position some way within the
line of deep water I cannot explain, without it be, that a depth somewhat
less than that close to the outer margin of the banks, is most favourable
to their growth.  Where the corals have formed a nearly continuous rim,
close to the windward edge of a bank some fathoms submerged, the reef
closely resembles an atoll; but if the bank surrounds an island (as in the
case of Old Providence), the reef resembles an encircling barrier-reef.  I
should undoubtedly have classed some of these fringed banks as imperfect
atolls, or barrier-reefs, if the sedimentary nature of their foundations
had not been evident from the presence of other neighbouring banks, of
similar forms and of similar composition, but without the crescent-like
marginal reef: in the third chapter, I observed that probably some atoll-like
reefs did exist, which had originated in the manner here supposed.

Proofs of elevation within recent tertiary periods abound, as referred to
in the sixth chapter, over nearly the whole area of the West Indies.  Hence
it is easy to understand the origin of the low land on the coasts, where
sediment is now accumulating; for instance on the northern part of Yucutan,
and on the N.E. part of Mosquito, where the land is low, and where
extensive banks appear to be in progressive formation.  Hence, also, the
origin of the Great Bahama Banks, which are bordered on their western and
southern edges by very narrow, long, singularly shaped islands, formed of
sand, shells, and coral-rock, and some of them about a hundred feet in
height, is easily explained by the elevation of banks fringed on their
windward (western and southern) sides by coral-reefs.  On this view,
however, we must suppose either that the chief part of the surfaces of the
great Bahama sandbanks were all originally deeply submerged, and were
brought up to their present level by the same elevatory action, which
formed the linear islands; or that during the elevation of the banks, the
superficial currents and swell of the waves continued wearing them down and
keeping them at a nearly uniform level: the level is not quite uniform;
for, in proceeding from the N.W. end of the Bahama group towards the S.E.
end, the depth of the banks increases, and the area of land decreases, in a
very gradual and remarkable manner.  The latter view, namely, that these
banks have been worn down by the currents and swell during their elevation,
seems to me the most probable one.  It is, also, I believe, applicable to
many banks, situated in widely distant parts of the West Indian Sea, which
are wholly submerged; for, on any other view, we must suppose, that the
elevatory forces have acted with astonishing uniformity.

The shores of the Gulf of Mexico, for the space of many hundred miles, is
formed by a chain of lagoons, from one to twenty miles in breadth
("Columbian Navigator," page 178, etc.), containing either fresh or salt
water, and separated from the sea by linear strips of sand.  Great spaces
of the shores of Southern Brazil (In the "London and Edinburgh
Philosophical Journal," 1841, page 257, I have described a singular bar of
sandstone lying parallel to the coast off Pernambuco in Brazil, which
probably is an analogous formation.), and of the United States from Long
Island (as observed by Professor Rogers) to Florida have the same
character.  Professor Rogers, in his "Report to the British Association"
(volume iii., page 13), speculates on the origin of these low, sandy,
linear islets; he states that the layers of which they are composed are too
homogeneous, and contain too large a proportion of shells, to permit the
common supposition of their formation being simply due to matter thrown up,
where it now lies, by the surf: he considers these islands as upheaved
bars or shoals, which were deposited in lines where opposed currents met.
It is evident that these islands and spits of sand parallel to the coast,
and separated from it by shallow lagoons, have no necessary connection with
coral-formations.  But in Southern Florida, from the accounts I have
received from persons who have resided there, the upraised islands seem to
be formed of strata, containing a good deal of coral, and they are
extensively fringed by living reefs; the channels within these islands are
in some places between two and three miles wide, and five or six fathoms
deep, though generally (In the ordinary sea-charts, no lagoons appear on
the coast of Florida, north of 26 deg; but Major Whiting ("Silliman's
Journal," volume xxxv., page 54) says that many are formed by sand thrown
up along the whole line of coast from St. Augustine's to Jupiter Inlet.)
they are less in depth than width.  After having seen how frequently banks
of sediment in the West Indian Sea are fringed by reefs, we can readily
conceive that bars of sediment might be greatly aided in their formation
along a line of coast, by the growth of corals; and such bars would, in
that case, have a deceptive resemblance with true barrier-reefs.

Having now endeavoured to remove some sources of doubt in classifying the
reefs of the West Indies, I will give my authorities for colouring such
portions of the coast as I have thought myself warranted in doing.  Captain
Bird Allen informs me, that most of the islands on the BAHAMA BANKS are
fringed, especially on their windward sides, with living reefs; and hence I
have coloured those, which are thus represented in Captain Owen's late
chart, red.  The same officer informs me, that the islands along the
southern part of FLORIDA are similarly fringed; coloured red.  CUBA:
Proceeding along the northern coast, at the distance of forty miles from
the extreme S.E. point, the shores are fringed by reefs, which extend
westward for a space of 160 miles, with only a few breaks.  Parts of these
reefs are represented in the plans of the harbours on this coast by Captain
Owen; and an excellent description is given of them by Mr. Taylor (Loudon's
"Mag. of Nat. Hist." volume ix., page 449); he states that they enclosed a
space called the "baxo," from half to three-quarters of a mile in width,
with a sandy bottom, and a little coral.  In most parts people can wade, at
low water, to the reef; but in some parts the depth is between two and
three fathoms.  Close outside the reef, the depth is between six and seven
fathoms; these well-characterised fringing-reefs are coloured red.
Westward of longitude 77 deg 30', on the northern side of Cuba, a great
bank commences, which extends along the coast for nearly four degrees of
longitude.  In the place of its commencement, in its structure, and in the
"CAYS," or low islands on its edge, there is a marked correspondence (as
observed by Humboldt, "Pers. Narr." volume vii., page 88) between it and
the Great Bahama and Sal Banks, which lie directly in front.  Hence one is
led to attribute the same origin to both these sets of banks; namely, the
accumulation of sediment, conjoined with an elevatory movement, and the
growth of coral on their outward edges; those parts which appear fringed by
living reefs are coloured red.  Westward of these banks, there is a portion
of coast apparently without reefs, except in the harbours, the shores of
which seem in the published plans to be fringed.  The COLORADO SHOALS (see
Captain Owen's charts), and the low land at the western end of Cuba,
correspond as closely in relative position and structure to the banks at
the extreme point of Florida, as the banks above described on the north
side of Cuba, do to the Bahamas, the depth within the islets and reefs on
the outer edge of the COLORADOS, is generally between two and three
fathoms, increasing to twelve fathoms in the southern part, where the bank
becomes nearly open, without islets or coral-reefs; the portions which are
fringed are coloured red.  The southern shore of Cuba is deeply concave,
and the included space is filled up with mud and sandbanks, low islands and
coral-reefs.  Between the mountainous ISLE OF PINES and the southern shore
of Cuba, the general depth is only between two and three fathoms; and in
this part small islands, formed of fragmentary rock and broken madrepores
(Humboldt, "Pers. Narr." volume vii. pages 51, 86 to 90, 291, 309, 320),
rise abruptly, and just reach the surface of the sea.  From some
expressions used in the "Columbian Navigator" (volume i., part ii., page
94), it appears that considerable spaces along the outer coast of Southern
Cuba are bounded by cliffs of coral-rock, formed probably by the upheaval
of coral-reefs and sandbanks.  The charts represent the southern part of
the Isle of Pines as fringed by reefs, which the "Columb. Navig." says
extend some way from the coast, but have only from nine to twelve feet
water on them; these are coloured red.--I have not been able to procure any
detailed description of the large groups of banks and "cays" further
eastward on the southern side of Cuba; within them there is a large
expanse, with a muddy bottom, from eight to twelve fathoms deep; although
some parts of this line of coast are represented in the general charts of
the West Indies, as fringed, I have not thought it prudent to colour them.
The remaining portion of the south coast of Cuba appears to be without
coral-reefs.

YUCUTAN.

The N.E. part of the promontory appears in Captain Owen's charts to be
fringed; coloured red.  The eastern coast, from 20 deg to 18 deg is
fringed.  South of latitude 18 deg, there commences the most remarkable
reef in the West Indies: it is about one hundred and thirty miles in
length, ranging in a N. and S. line, at an average distance of fifteen
miles from the coast.  The islets on it are all low, as I have been
informed by Captain B. Allen; the water deepens suddenly on the outside of
the reef, but not more abruptly than off many of the sedimentary banks:
within its southern extremity (off HONDURAS) the depth is twenty-five
fathoms; but in the more northern parts, the depth soon increases to ten
fathoms, and within the northernmost part, for a space of twenty miles, the
depth is only from one to two fathoms.  In most of these respects we have
the characteristics of a barrier-reef; nevertheless, from observing, first,
that the channel within the reef is a continuation of a great irregular
bay, which penetrates the mainland to the depth of fifty miles; and
secondly, that considerable spaces of this barrier-like reef are described
in the charts (for instance, in latitude 16 deg 45' and 16 deg 12') as
formed of pure sand; and thirdly, from knowing that sediment is
accumulating in many parts of the West Indies in banks parallel to the
shore; I have not ventured to colour this reef as a barrier, without
further evidence that it has really been formed by the growth of corals,
and that it is not merely in parts a spit of sand, and in other parts a
worn down promontory, partially coated and fringed by reefs; I lean,
however, to the probability of its being a barrier-reef, produced by
subsidence.  To add to my doubts, immediately on the outside of this
barrier-like reef, TURNEFFE, LIGHTHOUSE, and GLOVER reefs are situated, and
these reefs have so completely the form of atolls, that if they had
occurred in the Pacific, I should not have hesitated about colouring them
blue.  TURNEFFE REEF seems almost entirely filled up with low mud islets;
and the depth within the other two reefs is only from one to three fathoms.
From this circumstance and from their similarity in form, structure, and
relative position, both to the bank called NORTHERN TRIANGLES, on which
there is an islet between seventy and eighty feet, and to COZUMEL Island,
the level surface of which is likewise between seventy and eighty feet in
height, I consider it more probable that the three foregoing banks are the
worn down bases of upheaved shoals, fringed with corals, than that they are
true atolls, wholly produced by the growth of coral during subsidence; left
uncoloured.

In front of the eastern MOSQUITO coast, there are between latitude 12 deg
and 16 deg some extensive banks (already mentioned, page 148), with high
islands rising from their centres; and there are other banks wholly
submerged, both of which kinds of banks are bordered, near their windward
margins, by crescent-shaped coral-reefs.  But it can hardly be doubted, as
was observed in the preliminary remarks, that these banks owe their origin,
like the great bank extending from the Mosquito promontory, almost entirely
to the accumulation of sediment, and not to the growth of corals; hence I
have not coloured them.

CAYMAN ISLAND: this island appears in the charts to be fringed; and
Captain B. Allen informs me that the reefs extend about a mile from the
shore, and have only from five to twelve feet water within them; coloured
red.--JAMAICA: judging from the charts, about fifteen miles of the S.E.
extremity, and about twice that length on the S.W. extremity, and some
portions on the S. side near Kingston and Port Royal, are regularly
fringed, and therefore are coloured red.  From the plans of some harbours
on the N. side of Jamaica, parts of the coast appear to be fringed; but as
these are not represented in the charts of the whole island, I have not
coloured them.--ST. DOMINGO: I have not been able to obtain sufficient
information, either from plans of the harbours, or from general charts, to
enable me to colour any part of the coast, except sixty miles from Port de
Plata westward, which seems very regularly fringed; many other parts,
however, of the coast are probably fringed, especially towards the eastern
end of the island.--PUERTO RICO: considerable portions of the southern,
western, and eastern coasts, and some parts of the northern coast, appear
in the charts to be fringed; coloured red.--Some miles in length of the
southern side of the Island of ST. THOMAS is fringed; most of the VIRGIN
GORDA Islands, as I am informed by Mr. Schomburgk, are fringed; the shores
of ANEGADA, as well as the bank on which it stands, are likewise fringed;
these islands have been coloured red.  The greater part of the southern
side of SANTA CRUZ appears in the Danish survey to be fringed (see also
Prof. Hovey's account of this island, in "Silliman's Journal," volume
xxxv., page 74); the reefs extend along the shore for a considerable space,
and project rather more than a mile; the depth within the reef is three
fathoms; coloured red.--The ANTILLES, as remarked by Von Buch ("Descrip.
Iles Canaries," page 494), may be divided into two linear groups, the
western row being volcanic, and the eastern of modern calcareous origin; my
information is very defective on the whole group.  Of the eastern islands,
BARBUDA and the western coasts of ANTIGUA and MARIAGALANTE appear to be
fringed: this is also the case with BARBADOES, as I have been informed by
a resident; these islands are coloured red.  On the shores of the Western
Antilles, of volcanic origin, very few coral-reefs appear to exist.  The
island of MARTINIQUE, of which there are beautifully executed French
charts, on a very large scale, alone presents any appearance worthy of
special notice.  The south-western, southern, and eastern coasts, together
forming about half the circumference of the island, are skirted by very
irregular banks, projecting generally rather less than a mile from the
shore, and lying from two to five fathoms submerged.  In front of almost
every valley, they are breached by narrow, crooked, steep-sided passages.
The French engineers ascertained by boring, that these submerged banks
consisted of madreporitic rocks, which were covered in many parts by thin
layers of mud or sand.  From this fact, and especially from the structure
of the narrow breaches, I think there can be little doubt that these banks
once formed living reefs, which fringed the shores of the island, and like
other reefs probably reached the surface.  From some of these submerged
banks reefs of living coral rise abruptly, either in small detached
patches, or in lines parallel to, but some way within the outer edges of
the banks on which they are based.  Besides the above banks which skirt the
shores of the island, there is on the eastern side a range of linear banks,
similarly constituted, twenty miles in length, extending parallel to the
coast line, and separated from it by a space between two and four miles in
width, and from five to fifteen fathoms in depth.  From this range of
detached banks, some linear reefs of living coral likewise rise abruptly;
and if they had been of greater length (for they do not front more than a
sixth part of the circumference of the island), they would necessarily from
their position have been coloured as barrier-reefs; as the case stands they
are left uncoloured.  I suspect that after a small amount of subsidence,
the corals were killed by sand and mud being deposited on them, and the
reefs being thus prevented from growing upwards, the banks of madreporitic
rock were left in their present submerged condition.

THE BERMUDA Islands have been carefully described by Lieutenant Nelson, in
an excellent Memoir in the "Geological Transactions" (volume v., part i.,
page 103).  In the form of the bank or reef, on one side of which the
islands stand, there is a close general resemblance to an atoll; but in the
following respects there is a considerable difference,--first, in the
margin of the reef not forming (as I have been informed by Mr. Chaffers,
R.N.) a flat, solid surface, laid bare at low water, and regularly bounding
the internal space of shallow water or lagoon; secondly, in the border of
gradually shoaling water, nearly a mile and a half in width, which
surrounds the entire outside of the reef (as is laid down in Captain Hurd's
chart); and thirdly, in the size, height, and extraordinary form of the
islands, which present little resemblance to the long, narrow, simple
islets, seldom exceeding half a mile in breadth, which surmount the annular
reefs of almost all the atolls in the Indian and Pacific Oceans.  Moreover,
there are evident proofs (Nelson, Ibid., page 118), that islands similar to
the existing ones, formerly extended over other parts of the reef.  It
would, I believe, be difficult to find a true atoll with land exceeding
thirty feet in height; whereas, Mr. Nelson estimates the highest point of
the Bermuda Islands to be 260 feet; if, however, Mr. Nelson's view, that
the whole of the land consists of sand drifted by the winds, and
agglutinated together, were proved correct, this difference would be
immaterial; but, from his own account (page 118), there occur in one place,
five or six layers of red earth, interstratified with the ordinary
calcareous rock, and including stones too heavy for the wind to have moved,
without having at the same time utterly dispersed every grain of the
accompanying drifted matter.  Mr. Nelson attributes the origin of these
several layers, with their embedded stones, to as many violent
catastrophes; but further investigation in such cases has generally
succeeded in explaining phenomena of this kind by ordinary and simpler
means.  Finally, I may remark, that these islands have a considerable
resemblance in shape to Barbuda in the West Indies, and to Pemba on the
eastern coast of Africa, which latter island is about two hundred feet in
height, and consists of coral-rock.  I believe that the Bermuda Islands,
from being fringed by living reefs, ought to have been coloured red; but I
have left them uncoloured, on account of their general resemblance in
external form to a lagoon-island or atoll.


INDEX.

The names not in capitals are all names of places, and refer exclusively to
the Appendix: in well-defined archipelagoes, or groups of islands, the
name of each separate island is not given.

ABROLHOS, Brazil, coated by corals.

Abrolhos (Australia).

ABSENCE of coral-reefs from certain coasts.

Acaba, gulf of.

Admiralty group.

AFRICA, east coast, fringing-reef of.
Madreporitic rock of.

Africa, east coast.

AGE of individual corals.

Aiou.

Aitutaki.

Aldabra.

Alert reef.

Alexander, Grand Duke, island.

ALLAN, Dr., on Holuthuriae feeding on corals.
On quick growth of corals at Madagascar.
On reefs affected by currents.

Alloufatou.

Alphonse.

Amargoura. (Amargura.)

Amboina.

America, west coast.

Amirantes.

Anachorites.

Anambas.

ANAMOUKA, description of.

Anamouka.

Anadaman islands.

Antilles.

Appoo reef.

Arabia Felix.

AREAS, great extent of, interspersed with low islands.
Of subsidence and of elevation.
Of subsidence appear to be elongated.
Of subsidence alternating with areas of elevation.

Arru group.

Arzobispo.

ASCIDIA, depth at which found.

Assomption.

Astova.

Atlantic islands.

ATOLLS, breaches in their reefs.
Dimensions of.
Dimensions of groups of.
Not based on craters or on banks of sediment, or of rock.
Of irregular forms.
Steepness of their flanks.
Width of their reef and islets.
Their lowness.
Lagoons.
General range.
With part of their reef submerged, and theory of.

Augustine, St.

AURORA island, an upraised atoll.

Aurora.

AUSTRAL islands, recently elevated.

Austral islands.

Australia, N.W. coast.

AUSTRALIAN barrier-reef.

Australian barrier.

Babuyan group.

Bahama banks.

Balahac.

Bally.

Baring.

BARRIER-REEF of Australia.
Of New Caledonia.

BARRIER-REEFS, breaches through.
Not based on worn down margin of rock.
On banks of sediment.
On submarine craters.
Steepness of their flanks.
Their probable vertical thickness.
Theory of their formation.

Bampton shoal.

Banks islands.

Banks in the West Indies.

Bashee islands.

Bass island.

Batoa.

Beaupre reef.

BEECHEY, Captain, obligations of the author to.
On submerged reefs.
Account of Matilda island.

BELCHER, Captain, on boring through coral-reef.

Belize reef, off.

Bellinghausen.

Bermuda islands.

Beveridge reef.

Bligh.

BOLABOLA, view of.

Bombay shoal.

Bonin Bay.

Bonin group.

BORINGS through coral-reefs.

BORNEO, W. coast, recently elevated.

Borneo, E. coast.
S.W. and W. coast
N. coast.
Western bank.

Boscawen.

Boston.

Bouka.

Bourbon.

Bourou.

Bouton.

BRAZIL, fringing-reefs on coast of.

BREACHES through barrier-reefs.

Brook.

Bunker.

Bunoa.

BYRON.

Cagayanes.

Candelaria.

Cargados Carajos.

Caroline archipelago.

Caroline island.

Carteret shoal.

CARYOPHYLLIA, depth at which it lives.

Cavilli.

Cayman island.

Celebes.

Ceram.

CEYLON, recently elevated.

Ceylon.

CHAGOS Great Bank, description and theory of.

CHAGOS group.

Chagos group.

CHAMA-SHELLS embedded in coral-rock.

CHAMISSO, on corals preferring the surf.

CHANGES in the state of Keeling atoll.
Of atolls.

CHANNELS leading into the lagoons of atolls.
Into the Maldiva atolls.
Through barrier-reefs.

Chase.

China sea.

CHRISTMAS atoll.

Christmas atoll.

Christmas island (Indian Ocean).

Clarence.

Clipperton rock.

COCOS, or Keeling atoll.

Cocos (or Keeling).

Cocos island (Pacific).

COCHIN China, encroachments of the sea on the coast.

Cochin China.

Coetivi.

Comoro group.

COMPOSITION of coral-formations.

CONGLOMERATE coral-rock on Keeling atoll.
On other atolls.
Coral-rock.

COOK islands, recently elevated.

Cook islands.

CORAL-BLOCKS bored by vermiform animals.

CORAL-REEFS, their distribution and absence from certain areas.
Destroyed by loose sediment.

CORAL-ROCK at Keeling atoll.
Mauritius.
Organic remains of.

CORALS dead but upright in Keeling lagoon.
Depths at which they live.
Off Keeling atoll.
Killed by a short exposure.
Living in the lagoon of Keeling atoll.
Quick growth of, in Keeling lagoon.
Merely coating the bottom of the sea.
Standing exposed in the Low archipelago.

CORALLIAN sea.

Corallian sea.

Cornwallis.

Cosmoledo.

COUTHOUY, Mr., alleged proofs of recent elevation of the Low archipelago.
On coral-rock at Mangaia and Aurora islands.
On external ledges round coral-islands.
Remarks confirmatory of the author's theory.

CRESCENT-FORMED reefs.

Cuba.

CUMING, Mr., on the recent elevation of the Philippines.

Dangerous, or Low archipelago.

Danger islands.

DEPTHS at which reef-building corals live.
At Mauritius, the Red Sea, and in the Maldiva archipelago.
At which other corals and corallines can live.

Dhalac group.

DIEGO GARCIA, slow growth of reef.

DIMENSIONS of the larger groups of atolls.

DISSEVERMENT of the Maldiva atolls, and theory of.

DISTRIBUTION of coral-reefs.

Domingo, St.

DORY, Port, recently elevated.

Dory, Port.

Duff islands.

Durour.

Eap.

EARTHQUAKES at Keeling atoll.
In groups of atolls.
In Navigator archipelago.

EAST INDIAN ARCHIPELAGO, recently elevated.

Easter.

Echequier.

EHRENBERG, on the banks of the Red Sea.
On depths at which corals live in the Red Sea.
On corals preferring the surf.
On the antiquity of certain corals.

Eimeo.

ELEVATED reef of Mauritius.

ELEVATIONS, recent proofs of.
Immense areas of.

Elivi.

ELIZABETH island.
Recently elevated.

Elizabeth island.

Ellice group.

ENCIRCLED ISLANDS, their height.
Geological composition.

EOUA, description of.

Eoua.

ERUPTED MATTER probably not associated with thick masses of coral-rock.

FAIS, recently elevated.

Fais.

Fanning.

Farallon de Medinilla.

Farson group.

Fataka.

FIJI archipelago.

FISH, feeding on corals.
Killed in Keeling lagoon by heavy rain.

FISSURES across coral-islands.

FITZROY, Captain, on a submerged shed at Keeling atoll.
On an inundation in the Low archipelago.

Flint.

Flores.

Florida.

Folger.

Formosa.

FORSTER, theory of coral-formations.

Frederick reef.

Freewill.

FRIENDLY group recently elevated.

Friendly archipelago.

FRINGING-REEFS, absent where coast precipitous.
Breached in front of streams.
Described by MM. Quoy and Gaimard.
Not closely attached to shelving coasts.
Of east coast of Africa.
Of Cuba.
Of Mauritius.
On worn down banks of rock.
On banks of sediment.
Their appearance when elevated.
Their growth influenced by currents.
By shallowness of sea.

Galapagos archipelago.

Galega.

GAMBIER islands, section of.

Gambier islands.

Gardner.

Gaspar rico.

GEOLOGICAL COMPOSITION of coral-formations.

Gilbert archipelago.

Gilolo.

Glorioso.

GLOUCESTER Island.

Glover reef.

Gomez.

Gouap.

Goulou.

Grampus.

Gran Cocal.

GREAT CHAGOS BANK, description and theory of.

GREY, Captain, on sandbars.

GROUPING of the different classes of reefs.

Guedes.

HALL, Captain B., on Loo Choo.

HARVEY islands, recently elevated.

HEIGHT of encircled islands.

Hermites.

Hervey or Cook islands.

Hogoleu.

HOLOTHURIAE (Holuthuriae) feeding on coral.

HOUDEN island, height of.

Honduras, reef off.

Horn.

Houtman Abrolhos.

HUAHEINE; alleged proofs of its recent elevation.

Huaheine.

Humphrey.

Hunter.

HURRICANES, effects of, on coral-islands.

Immaum.

Independence.

INDIA, west coast, recently elevated.

India.

IRREGULAR REEFS in shallow seas.

ISLETS of coral-rock, their formation.
Their destruction in the Maldiva atolls.

Jamaica.

Jarvis.

JAVA, recently elevated.

Java.

Johnston island.

Juan de Nova.

Juan de Nova (Madagascar).

Kalatoa.

KAMTSCHATKA, proofs of its recent elevation.

Karkalang.

KEELING atoll, section of reef.

Keeling, south atoll.
North atoll.

Keffing.

Kemin.

Kennedy.

Keppel.

Kumi.

Laccadive group.

LADRONES, or Marianas, recently elevated.

Ladrones archipelago.

LAGOON of Keeling atoll.

LAGOONS bordered by inclined ledges and walls, and theory of their
formation.
Of small atolls filled up with sediment.

LAGOON-CHANNELS within barrier-reefs.

LAGOON-REEFS, all submerged in some atolls, and rising to the surface in
others.

Lancaster reef.

Latte.

Lauglan islands.

LEDGES round certain lagoons.

Lette.

Lighthouse reef.

LLOYD, Mr., on corals refixing themselves.

LOO CHOO, recently elevated.

Loo Choo.

Louisiade.

LOW ARCHIPELAGO, alleged proofs of its recent elevation.

Low archipelago.

LOWNESS of coral-islands.

Loyalty group.

Lucepara.

LUTKE, Admiral, on fissures across coral-islands.

LUZON, recently elevated.

Luzon.

LYELL, Mr., on channels into the lagoons of atolls.
On the lowness of their leeward sides.
On the antiquity of certain corals.
On the apparent continuity of distinct coral-islands.
On the recently elevated beds of the Red Sea.
On the outline of the areas of subsidence.

Macassar strait.

Macclesfield bank.

MADAGASCAR, quick growth of corals at.
Madreporitic rock of.

Madagascar.

Madjiko-sima.

Madura (Java).

Madura (India).

MAHLOS MAHDOO, theory of formation.

MALACCA, recently elevated.

Malacca.

MALCOLMSON, Dr., on recent elevation of W. coast of India.
On recent elevation of Camaran island.

Malden.

MALDIVA atolls, and theory of their formation.
Steepness of their flanks.
Growth of coral at.

Maldiva archipelago.

MANGAIA island.
Recently elevated.

Mangaia.

Mangs.

MARIANAS, recently elevated.

Mariana archipelago.

Mariere.

Marquesas archipelago.

Marshall archipelago.

Marshall island.

Martinique.

Martires.

MARY'S ST., in Madagascar, harbour made in reefs.

Mary island.

Matia, or Aurora.

MATILDA atoll.

MAURITIUS, fringing-reefs of.
Depths at which corals live there.
Recently elevated.

Mauritius.

MAURUA, section of.

Maurua.

MENCHIKOFF atoll.

Mendana archipelago.

Mendana isles.

Mexico, gulf of.

MILLEPORA COMPLANATA at Keeling atoll.

Mindoro.

Mohilla. (Mohila.)

MOLUCCA islands, recently elevated.

Mopeha.

MORESBY, Captain, on boring through coral-reefs.

Morty.

Mosquito coast.

MUSQUILLO atoll.

Mysol.

NAMOURREK group.

Natunas.

NAVIGATOR archipelago, elevation of.

Navigator archipelago.

Nederlandisch.

NELSON, Lieutenant, on the consolidation of coral-rocks under water.
Theory of coral-formations.
On the Bermuda islands.

New Britain.

NEW CALEDONIA, steepness of its reefs.
Barrier-reef of.

New Caledonia.

New Guinea (E. end).

New Guinea (W. end).

New Hanover.

NEW HEBRIDES, recently elevated.

New Hebrides.

NEW IRELAND, recently elevated.

New Ireland.

New Nantucket.

Nicobar islands.

Niouha.

NULLIPORAE at Keeling atoll.
On the reefs of atolls.
On barrier-reefs.
Their wide distribution and abundance.

OBJECTIONS to the theory of subsidence.

Ocean islands.

Ono.

Onouafu. (Onouafou.)

Ormuz.

Oscar group.

OSCILLATIONS of level.

Ouallan, or Ualan. (Oualan.)

OULUTHY atoll.

Outong Java.

Palawan, S.W. coast.
N.W. coast.
Western bank.

Palmerston.

Palmyra.

Paracells.

Paraquas.

Patchow.

Pelew islands.

PEMBA island, singular form of.

Pemba.

Penrhyn.

Peregrino.

PERNAMBUCO, bar of sandstone at.

PERSIAN gulf, recently elevated.

Persian gulf.

PESCADO.

Pescadores.

Peyster group.

Philip.

PHILIPPINE archipelago, recently elevated.

Philippine archipelago.

Phoenix.

Piguiram.

Pitcairn.

PITT'S bank.

Pitt island.

Platte.

Pleasant.

PORITES, chief coral on margin of Keeling atoll.

Postillions.

POUYNIPETE.
Its probable subsidence.

Pouynipete.

Pratas shoal.

Proby.

Providence.

Puerto Rico.

Pulo Anna.

PUMICE floated to coral-islands.

Pylstaart.

PYRARD DE LAVAL, astonishment at the atolls in the Indian Ocean.

QUOY AND GAIMARD, depths at which corals live.
Description of reefs applicable only to fringing-reefs.

RANGE of atolls.

Rapa.

Rearson.

RED SEA, banks of rock coated by reefs.
Proofs of its recent elevation.
Supposed subsidence of.

Red Sea.

REEFS, irregular in shallow seas.
Rising to the surface in some lagoons and all submerged in others.
Their distribution.
Their absence from some coasts.

Revilla-gigedo.

RING-FORMED REEFS of the Maldiva atolls, and theory of.

Rodriguez.

Rosario.

Rose island.

Rotches.

Rotoumah.

Roug.

Rowley shoals.

RUPPELL, Dr., on the recent deposits of Red Sea.

Sable, ile de.

Sahia de Malha.

St. Pierre.

Sala.

Salomon archipelago. (Solomon.)

SAMOA, or Navigator archipelago, elevation of.

Samoa archipelago.

SAND-BARS parallel to coasts.

Sandal-wood.

SANDWICH archipelago, recently elevated.

Sandwich archipelago.

Sanserot.

Santa-Cruz group.

SAVAGE island, recently elevated.

Savage.

Savu.

Saya, or Sahia de Malha.

Scarborough shoal.

SCARUS feeding on corals.

Schouten.

Scilly.

SCORIAE floated to coral-islands.

Scott's reef.

SECTIONS of islands encircled by barrier-reefs.
Of Bolabola.

SEDIMENT in Keeling lagoon.
In other atolls.
Injurious to corals.
Transported from coral-islands far seaward.

Seniavine.

Serangani.

Seychelles.

SHIP-BOTTOM quickly coated with coral.

SMYTH island.

SOCIETY archipelago, stationary condition of.
Alleged proofs of recent elevation.

Society archipelago.

Socotra.

Solor.

SOOLOO islands, recently elevated.

Sooloo islands.

Souvaroff.

Spanish.

SPONGE, depths at which found.

Starbuck. (Slarbuck.)

STONES transported in roots of trees.

STORMS, effects of, on coral-islands.

STUTCHBURY, Mr., on the growth of an Agaricia.
On upraised corals in Society archipelago.

SUBSIDENCE of Keeling atoll.
Extreme slowness of.
Areas of, apparently elongated.
Areas of immense.
Great amount of.

Suez, gulf of.

Sulphur islands.

SUMATRA, recently elevated.

Sumatra.

Sumbawa.

SURF favourable to the growth of massive corals.

Swallow shoal.

Sydney island.

TAHITI, alleged proofs of its recent elevation.

Tahiti.

TEMPERATURE of the sea at the Galapagos archipelago.

Tenasserim.

Tenimber island.

Teturoa.

THEORIES on coral-formations.

THEORY OF subsidence, and objections to.

THICKNESS, vertical, of barrier-reefs.

Thomas, St.

Tikopia.

TIMOR, recently elevated.

Timor.

Timor-laut.

Tokan-Bessees.

Tongatabou.

Tonquin.

Toubai.

Toufoa. (Toofoa.)

Toupoua.

TRADITIONS OF CHANGE in coral-islands.

TRIDACNAE embedded in coral-rock.
Left exposed in the Low archipelago.

TUBULARIA, quick growth of.

Tumbelan.

Turneffe reef.

Turtle.

Ualan.

VANIKORO, section of.
Its state and changes in its reefs.

Vanikoro.

Vine reef.

Virgin Gorda.

Viti archipelago.

VOLCANIC islands, with living corals on their shores.
Matter, probably not associated with thick masses of coral-rock.

VOLCANOES, authorities for their position on the map.
Their presence determined by the movements in progress.
Absent or extinct in the areas of subsidence.

Waigiou.

Wallis island.

Washington.

Well's reef.

WELLSTEAD, Lieutenant, account of a ship coated with corals.

WEST INDIES, banks of sediment fringed by reefs.
Recently elevated.

West Indies.

WHITSUNDAY island, view of.
Changes in its state.

WILLIAMS, Rev. J., on traditions of the natives regarding coral-islands.
On antiquity of certain corals.

Wolchonsky.

Wostock.

Xulla islands.

York island.

Yucutan, coast of.

ZONES of different kinds of corals outside the same reefs.




During the successive reprints of the first edition of this work, published
in 1871, I was able to introduce several important corrections; and now
that more time has elapsed, I have endeavoured to profit by the fiery
ordeal through which the book has passed, and have taken advantage of all
the criticisms which seem to me sound.  I am also greatly indebted to a
large number of correspondents for the communication of a surprising number
of new facts and remarks.  These have been so numerous, that I have been
able to use only the more important ones; and of these, as well as of the
more important corrections, I will append a list.  Some new illustrations
have been introduced, and four of the old drawings have been replaced by
better ones, done from life by Mr. T.W. Wood.  I must especially call
attention to some observations which I owe to the kindness of Prof. Huxley
(given as a supplement at the end of Part I.), on the nature of the
differences between the brains of man and the higher apes.  I have been
particularly glad to give these observations, because during the last few
years several memoirs on the subject have appeared on the Continent, and
their importance has been, in some cases, greatly exaggerated by popular
writers.

I may take this opportunity of remarking that my critics frequently assume
that I attribute all changes of corporeal structure and mental power
exclusively to the natural selection of such variations as are often called
spontaneous; whereas, even in the first edition of the 'Origin of Species,'
I distinctly stated that great weight must be attributed to the inherited
effects of use and disuse, with respect both to the body and mind.  I also
attributed some amount of modification to the direct and prolonged action
of changed conditions of life.  Some allowance, too, must be made for
occasional reversions of structure; nor must we forget what I have called
"correlated" growth, meaning, thereby, that various parts of the
organisation are in some unknown manner so connected, that when one part
varies, so do others; and if variations in the one are accumulated by
selection, other parts will be modified.  Again, it has been said by
several critics, that when I found that many details of structure in man
could not be explained through natural selection, I invented sexual
selection; I gave, however, a tolerably clear sketch of this principle in
the first edition of the 'Origin of Species,' and I there stated that it
was applicable to man.  This subject of sexual selection has been treated
at full length in the present work, simply because an opportunity was here
first afforded me.  I have been struck with the likeness of many of the
half-favourable criticisms on sexual selection, with those which appeared
at first on natural selection; such as, that it would explain some few
details, but certainly was not applicable to the extent to which I have
employed it.  My conviction of the power of sexual selection remains
unshaken; but it is probable, or almost certain, that several of my
conclusions will hereafter be found erroneous; this can hardly fail to be
the case in the first treatment of a subject.  When naturalists have become
familiar with the idea of sexual selection, it will, as I believe, be much
more largely accepted; and it has already been fully and favourably
received by several capable judges.

DOWN, BECKENHAM, KENT,
September, 1874.

First Edition February 24, 1871.
Second Edition September, 1874.


CONTENTS.


INTRODUCTION.


PART I.  THE DESCENT OR ORIGIN OF MAN.


CHAPTER I.

The Evidence of the Descent of Man from some Lower Form.

Nature of the evidence bearing on the origin of man--Homologous structures
in man and the lower animals--Miscellaneous points of correspondence--
Development--Rudimentary structures, muscles, sense-organs, hair, bones,
reproductive organs, etc.--The bearing of these three great classes of
facts on the origin of man.


CHAPTER II.

On the Manner of Development of Man from some Lower Form.

Variability of body and mind in man--Inheritance--Causes of variability--
Laws of variation the same in man as in the lower animals--Direct action of
the conditions of life--Effects of the increased use and disuse of parts--
Arrested development--Reversion--Correlated variation--Rate of increase--
Checks to increase--Natural selection--Man the most dominant animal in the
world--Importance of his corporeal structure--The causes which have led to
his becoming erect--Consequent changes of structure--Decrease in size of
the canine teeth--Increased size and altered shape of the skull--Nakedness
--Absence of a tail--Defenceless condition of man.


CHAPTER III.

Comparison of the Mental Powers of Man and the Lower Animals.

The difference in mental power between the highest ape and the lowest
savage, immense--Certain instincts in common--The emotions--Curiosity--
Imitation--Attention--Memory--Imagination--Reason--Progressive improvement
--Tools and weapons used by animals--Abstraction, Self-consciousness--
Language--Sense of beauty--Belief in God, spiritual agencies,
superstitions.


CHAPTER IV.

Comparison of the Mental Powers of Man and the Lower Animals--continued.

The moral sense--Fundamental proposition--The qualities of social animals--
Origin of sociability--Struggle between opposed instincts--Man a social
animal--The more enduring social instincts conquer other less persistent
instincts--The social virtues alone regarded by savages--The self-regarding
virtues acquired at a later stage of development--The importance of the
judgment of the members of the same community on conduct--Transmission of
moral tendencies--Summary.


CHAPTER V.

On the Development of the Intellectual and Moral Faculties during Primeval
and Civilised times.

Advancement of the intellectual powers through natural selection--
Importance of imitation--Social and moral faculties--Their development
within the limits of the same tribe--Natural selection as affecting
civilised nations--Evidence that civilised nations were once barbarous.


CHAPTER VI.

On the Affinities and Genealogy of Man.

Position of man in the animal series--The natural system genealogical--
Adaptive characters of slight value--Various small points of resemblance
between man and the Quadrumana--Rank of man in the natural system--
Birthplace and antiquity of man--Absence of fossil connecting-links--Lower
stages in the genealogy of man, as inferred firstly from his affinities and
secondly from his structure--Early androgynous condition of the Vertebrata
--Conclusion.


CHAPTER VII.

On the Races of Man.

The nature and value of specific characters--Application to the races of
man--Arguments in favour of, and opposed to, ranking the so-called races of
man as distinct species--Sub-species--Monogenists and polygenists--
Convergence of character--Numerous points of resemblance in body and mind
between the most distinct races of man--The state of man when he first
spread over the earth--Each race not descended from a single pair--The
extinction of races--The formation of races--The effects of crossing--
Slight influence of the direct action of the conditions of life--Slight or
no influence of natural selection--Sexual selection.


PART II.  SEXUAL SELECTION.


CHAPTER VIII.

Principles of Sexual Selection.

Secondary sexual characters--Sexual selection--Manner of action--Excess of
males--Polygamy--The male alone generally modified through sexual
selection--Eagerness of the male--Variability of the male--Choice exerted
by the female--Sexual compared with natural selection--Inheritance at
corresponding periods of life, at corresponding seasons of the year, and as
limited by sex--Relations between the several forms of inheritance--Causes
why one sex and the young are not modified through sexual selection--
Supplement on the proportional numbers of the two sexes throughout the
animal kingdom-- The proportion of the sexes in relation to natural
selection.


CHAPTER IX.

Secondary Sexual Characters in the Lower Classes of the Animal Kingdom.

These characters are absent in the lowest classes--Brilliant colours--
Mollusca--Annelids--Crustacea, secondary sexual characters strongly
developed; dimorphism; colour; characters not acquired before maturity--
Spiders, sexual colours of; stridulation by the males--Myriapoda.


CHAPTER X.

Secondary Sexual Characters of Insects.

Diversified structures possessed by the males for seizing the females--
Differences between the sexes, of which the meaning is not understood--
Difference in size between the sexes--Thysanura--Diptera--Hemiptera--
Homoptera, musical powers possessed by the males alone--Orthoptera, musical
instruments of the males, much diversified in structure; pugnacity;
colours--Neuroptera, sexual differences in colour--Hymenoptera, pugnacity
and odours--Coleoptera, colours; furnished with great horns, apparently as
an ornament; battles; stridulating organs generally common to both sexes.


CHAPTER XI.

Insects, continued.--Order Lepidoptera.

(Butterflies and Moths.)

Courtship of Butterflies--Battles--Ticking noise--Colours common to both
sexes, or more brilliant in the males--Examples--Not due to the direct
action of the conditions of life--Colours adapted for protection--Colours
of moths--Display--Perceptive powers of the Lepidoptera--Variability--
Causes of the difference in colour between the males and females--Mimicry,
female butterflies more brilliantly coloured than the males--Bright colours
of caterpillars--Summary and concluding remarks on the secondary sexual
character of insects--Birds and insects compared.


CHAPTER XII.

Secondary Sexual Characters of Fishes, Amphibians, and Reptiles.

Fishes:  Courtship and battles of the males--Larger size of the females--
Males, bright colours and ornamental appendages; other strange characters--
Colours and appendages acquired by the males during the breeding-season
alone--Fishes with both sexes brilliantly coloured--Protective colours--The
less conspicuous colours of the female cannot be accounted for on the
principle of protection--Male fishes building nests, and taking charge of
the ova and young.  AMPHIBIANS:  Differences in structure and colour
between the sexes--Vocal organs.  REPTILES:  Chelonians--Crocodiles--
Snakes, colours in some cases protective--Lizards, battles of--Ornamental
appendages--Strange differences in structure between the sexes--Colours--
Sexual differences almost as great as with birds.


CHAPTER XIII.

Secondary Sexual Characters of Birds.

Sexual differences--Law of battle--Special weapons--Vocal organs--
Instrumental music--Love-antics and dances--Decorations, permanent and
seasonal--Double and single annual moults--Display of ornaments by the
males.


CHAPTER XIV.

Birds--continued.

Choice exerted by the female--Length of courtship--Unpaired birds--Mental
qualities and taste for the beautiful--Preference or antipathy shewn by the
female for particular males--Variability of birds--Variations sometimes
abrupt--Laws of variation--Formation of ocelli--Gradations of character--
Case of Peacock, Argus pheasant, and Urosticte.


CHAPTER XV.

Birds--continued.

Discussion as to why the males alone of some species, and both sexes of
others are brightly coloured--On sexually-limited inheritance, as applied
to various structures and to brightly-coloured plumage--Nidification in
relation to colour--Loss of nuptial plumage during the winter.


CHAPTER XVI.

Birds--concluded.

The immature plumage in relation to the character of the plumage in both
sexes when adult--Six classes of cases--Sexual differences between the
males of closely-allied or representative species--The female assuming the
characters of the male--Plumage of the young in relation to the summer and
winter plumage of the adults--On the increase of beauty in the birds of the
world--Protective colouring--Conspicuously coloured birds--Novelty
appreciated--Summary of the four chapters on birds.


CHAPTER XVII.

Secondary Sexual Characters of Mammals.

The law of battle--Special weapons, confined to the males--Cause of absence
of weapons in the female--Weapons common to both sexes, yet primarily
acquired by the male--Other uses of such weapons--Their high importance--
Greater size of the male--Means of defence--On the preference shewn by
either sex in the pairing of quadrupeds.


CHAPTER XVIII.

Secondary Sexual Characters of Mammals--continued.

Voice--Remarkable sexual peculiarities in seals--Odour--Development of the
hair--Colour of the hair and skin--Anomalous case of the female being more
ornamented than the male--Colour and ornaments due to sexual selection--
Colour acquired for the sake of protection--Colour, though common to both
sexes, often due to sexual selection--On the disappearance of spots and
stripes in adult quadrupeds--On the colours and ornaments of the
Quadrumana--Summary.


PART III.  SEXUAL SELECTION IN RELATION TO MAN, AND CONCLUSION.


CHAPTER XIX.

Secondary Sexual Characters of Man.

Differences between man and woman--Causes of such differences, and of
certain characters common to both sexes--Law of battle--Differences in
mental powers, and voice--On the influence of beauty in determining the
marriages of mankind--Attention paid by savages to ornaments--Their ideas
of beauty in women--The tendency to exaggerate each natural peculiarity.


CHAPTER XX.

Secondary Sexual Characters of Man--continued.

On the effects of the continued selection of women according to a different
standard of beauty in each race--On the causes which interfere with sexual
selection in civilised and savage nations--Conditions favourable to sexual
selection during primeval times--On the manner of action of sexual
selection with mankind--On the women in savage tribes having some power to
choose their husbands--Absence of hair on the body, and development of the
beard--Colour of the skin--Summary.


CHAPTER XXI.

General Summary and Conclusion.

Main conclusion that man is descended from some lower form--Manner of
development--Genealogy of man--Intellectual and moral faculties--Sexual
selection--Concluding remarks.


SUPPLEMENTAL NOTE.


INDEX.



THE DESCENT OF MAN; AND SELECTION IN RELATION TO SEX.

...

INTRODUCTION.

The nature of the following work will be best understood by a brief account
of how it came to be written.  During many years I collected notes on the
origin or descent of man, without any intention of publishing on the
subject, but rather with the determination not to publish, as I thought
that I should thus only add to the prejudices against my views.  It seemed
to me sufficient to indicate, in the first edition of my 'Origin of
Species,' that by this work "light would be thrown on the origin of man and
his history;" and this implies that man must be included with other organic
beings in any general conclusion respecting his manner of appearance on
this earth.  Now the case wears a wholly different aspect.  When a
naturalist like Carl Vogt ventures to say in his address as President of
the National Institution of Geneva (1869), "personne, en Europe au moins,
n'ose plus soutenir la creation independante et de toutes pieces, des
especes," it is manifest that at least a large number of naturalists must
admit that species are the modified descendants of other species; and this
especially holds good with the younger and rising naturalists.  The greater
number accept the agency of natural selection; though some urge, whether
with justice the future must decide, that I have greatly overrated its
importance.  Of the older and honoured chiefs in natural science, many
unfortunately are still opposed to evolution in every form.

In consequence of the views now adopted by most naturalists, and which will
ultimately, as in every other case, be followed by others who are not
scientific, I have been led to put together my notes, so as to see how far
the general conclusions arrived at in my former works were applicable to
man.  This seemed all the more desirable, as I had never deliberately
applied these views to a species taken singly.  When we confine our
attention to any one form, we are deprived of the weighty arguments derived
from the nature of the affinities which connect together whole groups of
organisms--their geographical distribution in past and present times, and
their geological succession.  The homological structure, embryological
development, and rudimentary organs of a species remain to be considered,
whether it be man or any other animal, to which our attention may be
directed; but these great classes of facts afford, as it appears to me,
ample and conclusive evidence in favour of the principle of gradual
evolution.  The strong support derived from the other arguments should,
however, always be kept before the mind.

The sole object of this work is to consider, firstly, whether man, like
every other species, is descended from some pre-existing form; secondly,
the manner of his development; and thirdly, the value of the differences
between the so-called races of man.  As I shall confine myself to these
points, it will not be necessary to describe in detail the differences
between the several races--an enormous subject which has been fully
described in many valuable works.  The high antiquity of man has recently
been demonstrated by the labours of a host of eminent men, beginning with
M. Boucher de Perthes; and this is the indispensable basis for
understanding his origin.  I shall, therefore, take this conclusion for
granted, and may refer my readers to the admirable treatises of Sir Charles
Lyell, Sir John Lubbock, and others.  Nor shall I have occasion to do more
than to allude to the amount of difference between man and the
anthropomorphous apes; for Prof. Huxley, in the opinion of most competent
judges, has conclusively shewn that in every visible character man differs
less from the higher apes, than these do from the lower members of the same
order of Primates.

This work contains hardly any original facts in regard to man; but as the
conclusions at which I arrived, after drawing up a rough draft, appeared to
me interesting, I thought that they might interest others.  It has often
and confidently been asserted, that man's origin can never be known:  but
ignorance more frequently begets confidence than does knowledge:  it is
those who know little, and not those who know much, who so positively
assert that this or that problem will never be solved by science.  The
conclusion that man is the co-descendant with other species of some
ancient, lower, and extinct form, is not in any degree new.  Lamarck long
ago came to this conclusion, which has lately been maintained by several
eminent naturalists and philosophers; for instance, by Wallace, Huxley,
Lyell, Vogt, Lubbock, Buchner, Rolle, etc. (1.  As the works of the first-
named authors are so well known, I need not give the titles; but as those
of the latter are less well known in England, I will give them:--'Sechs
Vorlesungen ueber die Darwin'sche Theorie:'  zweite Auflage, 1868, von Dr L.
Buchner; translated into French under the title 'Conferences sur la Theorie
Darwinienne,' 1869.  'Der Mensch im Lichte der Darwin'sche Lehre,' 1865,
von Dr. F. Rolle.  I will not attempt to give references to all the authors
who have taken the same side of the question.  Thus G. Canestrini has
published ('Annuario della Soc. d. Nat.,' Modena, 1867, page 81) a very
curious paper on rudimentary characters, as bearing on the origin of man.
Another work has (1869) been published by Dr. Francesco Barrago, bearing in
Italian the title of "Man, made in the image of God, was also made in the
image of the ape."), and especially by Haeckel.  This last naturalist,
besides his great work, 'Generelle Morphologie' (1866), has recently (1868,
with a second edition in 1870), published his 'Natuerliche
Schoepfungsgeschichte,' in which he fully discusses the genealogy of man.
If this work had appeared before my essay had been written, I should
probably never have completed it.  Almost all the conclusions at which I
have arrived I find confirmed by this naturalist, whose knowledge on many
points is much fuller than mine.  Wherever I have added any fact or view
from Prof. Haeckel's writings, I give his authority in the text; other
statements I leave as they originally stood in my manuscript, occasionally
giving in the foot-notes references to his works, as a confirmation of the
more doubtful or interesting points.

During many years it has seemed to me highly probable that sexual selection
has played an important part in differentiating the races of man; but in my
'Origin of Species' (first edition, page 199) I contented myself by merely
alluding to this belief.  When I came to apply this view to man, I found it
indispensable to treat the whole subject in full detail.  (2.  Prof.
Haeckel was the only author who, at the time when this work first appeared,
had discussed the subject of sexual selection, and had seen its full
importance, since the publication of the 'Origin'; and this he did in a
very able manner in his various works.)  Consequently the second part of
the present work, treating of sexual selection, has extended to an
inordinate length, compared with the first part; but this could not be
avoided.

I had intended adding to the present volumes an essay on the expression of
the various emotions by man and the lower animals.  My attention was called
to this subject many years ago by Sir Charles Bell's admirable work.  This
illustrious anatomist maintains that man is endowed with certain muscles
solely for the sake of expressing his emotions.  As this view is obviously
opposed to the belief that man is descended from some other and lower form,
it was necessary for me to consider it.  I likewise wished to ascertain how
far the emotions are expressed in the same manner by the different races of
man.  But owing to the length of the present work, I have thought it better
to reserve my essay for separate publication.


PART I.  THE DESCENT OR ORIGIN OF MAN.


CHAPTER I.

THE EVIDENCE OF THE DESCENT OF MAN FROM SOME LOWER FORM.

Nature of the evidence bearing on the origin of man--Homologous structures
in man and the lower animals--Miscellaneous points of correspondence--
Development--Rudimentary structures, muscles, sense-organs, hair, bones,
reproductive organs, etc.--The bearing of these three great classes of
facts on the origin of man.

He who wishes to decide whether man is the modified descendant of some pre-
existing form, would probably first enquire whether man varies, however
slightly, in bodily structure and in mental faculties; and if so, whether
the variations are transmitted to his offspring in accordance with the laws
which prevail with the lower animals.  Again, are the variations the
result, as far as our ignorance permits us to judge, of the same general
causes, and are they governed by the same general laws, as in the case of
other organisms; for instance, by correlation, the inherited effects of use
and disuse, etc.?  Is man subject to similar malconformations, the result
of arrested development, of reduplication of parts, etc., and does he
display in any of his anomalies reversion to some former and ancient type
of structure?  It might also naturally be enquired whether man, like so
many other animals, has given rise to varieties and sub-races, differing
but slightly from each other, or to races differing so much that they must
be classed as doubtful species?  How are such races distributed over the
world; and how, when crossed, do they react on each other in the first and
succeeding generations?  And so with many other points.

The enquirer would next come to the important point, whether man tends to
increase at so rapid a rate, as to lead to occasional severe struggles for
existence; and consequently to beneficial variations, whether in body or
mind, being preserved, and injurious ones eliminated.  Do the races or
species of men, whichever term may be applied, encroach on and replace one
another, so that some finally become extinct?  We shall see that all these
questions, as indeed is obvious in respect to most of them, must be
answered in the affirmative, in the same manner as with the lower animals.
But the several considerations just referred to may be conveniently
deferred for a time:  and we will first see how far the bodily structure of
man shews traces, more or less plain, of his descent from some lower form.
In succeeding chapters the mental powers of man, in comparison with those
of the lower animals, will be considered.

THE BODILY STRUCTURE OF MAN.

It is notorious that man is constructed on the same general type or model
as other mammals.  All the bones in his skeleton can be compared with
corresponding bones in a monkey, bat, or seal.  So it is with his muscles,
nerves, blood-vessels and internal viscera.  The brain, the most important
of all the organs, follows the same law, as shewn by Huxley and other
anatomists.  Bischoff (1. 'Grosshirnwindungen des Menschen,' 1868, s. 96.
The conclusions of this author, as well as those of Gratiolet and Aeby,
concerning the brain, will be discussed by Prof. Huxley in the Appendix
alluded to in the Preface to this edition.), who is a hostile witness,
admits that every chief fissure and fold in the brain of man has its
analogy in that of the orang; but he adds that at no period of development
do their brains perfectly agree; nor could perfect agreement be expected,
for otherwise their mental powers would have been the same.  Vulpian (2.
'Lec. sur la Phys.' 1866, page 890, as quoted by M. Dally, 'L'Ordre des
Primates et le Transformisme,' 1868, page 29.), remarks:  "Les differences
reelles qui existent entre l'encephale de l'homme et celui des singes
superieurs, sont bien minimes.  Il ne faut pas se faire d'illusions a cet
egard.  L'homme est bien plus pres des singes anthropomorphes par les
caracteres anatomiques de son cerveau que ceux-ci ne le sont non seulement
des autres mammiferes, mais meme de certains quadrumanes, des guenons et
des macaques."  But it would be superfluous here to give further details on
the correspondence between man and the higher mammals in the structure of
the brain and all other parts of the body.

It may, however, be worth while to specify a few points, not directly or
obviously connected with structure, by which this correspondence or
relationship is well shewn.

Man is liable to receive from the lower animals, and to communicate to
them, certain diseases, as hydrophobia, variola, the glanders, syphilis,
cholera, herpes, etc. (3.  Dr. W. Lauder Lindsay has treated this subject
at some length in the 'Journal of Mental Science,' July 1871; and in the
'Edinburgh Veterinary Review,' July 1858.); and this fact proves the close
similarity (4.  A Reviewer has criticised ('British Quarterly Review,' Oct.
1st, 1871, page 472) what I have here said with much severity and contempt;
but as I do not use the term identity, I cannot see that I am greatly in
error.  There appears to me a strong analogy between the same infection or
contagion producing the same result, or one closely similar, in two
distinct animals, and the testing of two distinct fluids by the same
chemical reagent.) of their tissues and blood, both in minute structure and
composition, far more plainly than does their comparison under the best
microscope, or by the aid of the best chemical analysis.  Monkeys are
liable to many of the same non-contagious diseases as we are; thus Rengger
(5.  'Naturgeschichte der Saeugethiere von Paraguay,' 1830, s. 50.), who
carefully observed for a long time the Cebus Azarae in its native land,
found it liable to catarrh, with the usual symptoms, and which, when often
recurrent, led to consumption.  These monkeys suffered also from apoplexy,
inflammation of the bowels, and cataract in the eye.  The younger ones when
shedding their milk-teeth often died from fever.  Medicines produced the
same effect on them as on us.  Many kinds of monkeys have a strong taste
for tea, coffee, and spiritous liquors:  they will also, as I have myself
seen, smoke tobacco with pleasure.  (6.  The same tastes are common to some
animals much lower in the scale.  Mr. A. Nichols informs me that he kept in
Queensland, in Australia, three individuals of the Phaseolarctus cinereus;
and that, without having been taught in any way, they acquired a strong
taste for rum, and for smoking tobacco.)  Brehm asserts that the natives of
north-eastern Africa catch the wild baboons by exposing vessels with strong
beer, by which they are made drunk.  He has seen some of these animals,
which he kept in confinement, in this state; and he gives a laughable
account of their behaviour and strange grimaces.  On the following morning
they were very cross and dismal; they held their aching heads with both
hands, and wore a most pitiable expression:  when beer or wine was offered
them, they turned away with disgust, but relished the juice of lemons.  (7.
Brehm, 'Thierleben,' B. i. 1864, s. 75, 86.  On the Ateles, s. 105.  For
other analogous statements, see s. 25, 107.)  An American monkey, an
Ateles, after getting drunk on brandy, would never touch it again, and thus
was wiser than many men.  These trifling facts prove how similar the nerves
of taste must be in monkeys and man, and how similarly their whole nervous
system is affected.

Man is infested with internal parasites, sometimes causing fatal effects;
and is plagued by external parasites, all of which belong to the same
genera or families as those infesting other mammals, and in the case of
scabies to the same species.  (8.  Dr. W. Lauder Lindsay, 'Edinburgh Vet.
Review,' July 1858, page 13.)  Man is subject, like other mammals, birds,
and even insects (9.  With respect to insects see Dr. Laycock, "On a
General Law of Vital Periodicity," 'British Association,' 1842.  Dr.
Macculloch, 'Silliman's North American Journal of Science,' vol. XVII. page
305, has seen a dog suffering from tertian ague.  Hereafter I shall return
to this subject.), to that mysterious law, which causes certain normal
processes, such as gestation, as well as the maturation and duration of
various diseases, to follow lunar periods.  His wounds are repaired by the
same process of healing; and the stumps left after the amputation of his
limbs, especially during an early embryonic period, occasionally possess
some power of regeneration, as in the lowest animals.  (10.  I have given
the evidence on this head in my 'Variation of Animals and Plants under
Domestication,' vol. ii. page 15, and more could be added.)

The whole process of that most important function, the reproduction of the
species, is strikingly the same in all mammals, from the first act of
courtship by the male (11.  Mares e diversis generibus Quadrumanorum sine
dubio dignoscunt feminas humanas a maribus.  Primum, credo, odoratu, postea
aspectu.  Mr. Youatt, qui diu in Hortis Zoologicis (Bestiariis) medicus
animalium erat, vir in rebus observandis cautus et sagax, hoc mihi
certissime probavit, et curatores ejusdem loci et alii e ministris
confirmaverunt.  Sir Andrew Smith et Brehm notabant idem in Cynocephalo.
Illustrissimus Cuvier etiam narrat multa de hac re, qua ut opinor, nihil
turpius potest indicari inter omnia hominibus et Quadrumanis communia.
Narrat enim Cynocephalum quendam in furorem incidere aspectu feminarum
aliquarem, sed nequaquam accendi tanto furore ab omnibus.  Semper eligebat
juniores, et dignoscebat in turba, et advocabat voce gestuque.), to the
birth and nurturing of the young.  Monkeys are born in almost as helpless a
condition as our own infants; and in certain genera the young differ fully
as much in appearance from the adults, as do our children from their
full-grown parents.  (12.  This remark is made with respect to Cynocephalus
and the anthropomorphous apes by Geoffroy Saint-Hilaire and F. Cuvier,
'Histoire Nat. des Mammiferes,' tom. i. 1824.)  It has been urged by some
writers, as an important distinction, that with man the young arrive at
maturity at a much later age than with any other animal: but if we look to
the races of mankind which inhabit tropical countries the difference is not
great, for the orang is believed not to be adult till the age of from ten
to fifteen years.  (13.  Huxley, 'Man's Place in Nature,' 1863, p. 34.)
Man differs from woman in size, bodily strength, hairiness, etc., as well
as in mind, in the same manner as do the two sexes of many mammals.  So
that the correspondence in general structure, in the minute structure of
the tissues, in chemical composition and in constitution, between man and
the higher animals, especially the anthropomorphous apes, is extremely
close.

EMBRYONIC DEVELOPMENT.

[Fig. 1.  Shows a human embryo, from Ecker, and a dog embryo, from
Bischoff.  Labelled in each are:

a.  Fore-brain, cerebral hemispheres, etc.
b.  Mid-brain, corpora quadrigemina.
c.  Hind-brain, cerebellum, medulla oblongata.
d.  Eye.
e.  Ear.
f.  First visceral arch.
g.  Second visceral arch.
H.  Vertebral columns and muscles in process of development.
i.  Anterior extremities.
K.  Posterior extremities.
L.  Tail or os coccyx.]

Man is developed from an ovule, about the 125th of an inch in diameter,
which differs in no respect from the ovules of other animals.  The embryo
itself at a very early period can hardly be distinguished from that of
other members of the vertebrate kingdom.  At this period the arteries run
in arch-like branches, as if to carry the blood to branchiae which are not
present in the higher Vertebrata, though the slits on the sides of the neck
still remain (see f, g, fig. 1), marking their former position.  At a
somewhat later period, when the extremities are developed, "the feet of
lizards and mammals," as the illustrious Von Baer remarks, "the wings and
feet of birds, no less than the hands and feet of man, all arise from the
same fundamental form."  It is, says Prof. Huxley (14.  'Man's Place in
Nature,' 1863, p. 67.), "quite in the later stages of development that the
young human being presents marked differences from the young ape, while the
latter departs as much from the dog in its developments, as the man does.
Startling as this last assertion may appear to be, it is demonstrably
true."

As some of my readers may never have seen a drawing of an embryo, I have
given one of man and another of a dog, at about the same early stage of
development, carefully copied from two works of undoubted accuracy.  (15.
The human embryo (upper fig.) is from Ecker, 'Icones Phys.,' 1851-1859,
tab. xxx. fig. 2.  This embryo was ten lines in length, so that the drawing
is much magnified.  The embryo of the dog is from Bischoff,
'Entwicklungsgeschichte des Hunde-Eies,' 1845, tab. xi. fig. 42B.  This
drawing is five times magnified, the embryo being twenty-five days old.
The internal viscera have been omitted, and the uterine appendages in both
drawings removed.  I was directed to these figures by Prof. Huxley, from
whose work, 'Man's Place in Nature,' the idea of giving them was taken.
Haeckel has also given analogous drawings in his 'Schopfungsgeschichte.')

After the foregoing statements made by such high authorities, it would be
superfluous on my part to give a number of borrowed details, shewing that
the embryo of man closely resembles that of other mammals.  It may,
however, be added, that the human embryo likewise resembles certain low
forms when adult in various points of structure.  For instance, the heart
at first exists as a simple pulsating vessel; the excreta are voided
through a cloacal passage; and the os coccyx projects like a true tail,
"extending considerably beyond the rudimentary legs."  (16.  Prof. Wyman in
'Proceedings of the American Academy of Sciences,' vol. iv. 1860, p. 17.)
In the embryos of all air-breathing vertebrates, certain glands, called the
corpora Wolffiana, correspond with, and act like the kidneys of mature
fishes.  (17.  Owen, 'Anatomy of Vertebrates,' vol. i. p. 533.)  Even at a
later embryonic period, some striking resemblances between man and the
lower animals may be observed.  Bischoff says that "the convolutions of the
brain in a human foetus at the end of the seventh month reach about the
same stage of development as in a baboon when adult."  (18.  'Die
Grosshirnwindungen des Menschen,' 1868, s. 95.)  The great toe, as
Professor Owen remarks (19.  'Anatomy of Vertebrates,' vol. ii. p. 553.),
"which forms the fulcrum when standing or walking, is perhaps the most
characteristic peculiarity in the human structure;" but in an embryo, about
an inch in length, Prof. Wyman (20.  'Proc. Soc. Nat. Hist.' Boston, 1863,
vol. ix. p. 185.) found "that the great toe was shorter than the others;
and, instead of being parallel to them, projected at an angle from the side
of the foot, thus corresponding with the permanent condition of this part
in the quadrumana."  I will conclude with a quotation from Huxley (21.
'Man's Place in Nature,' p. 65.) who after asking, does man originate in a
different way from a dog, bird, frog or fish? says, "the reply is not
doubtful for a moment; without question, the mode of origin, and the early
stages of the development of man, are identical with those of the animals
immediately below him in the scale: without a doubt in these respects, he
is far nearer to apes than the apes are to the dog."

RUDIMENTS.

This subject, though not intrinsically more important than the two last,
will for several reasons be treated here more fully.  (22.  I had written a
rough copy of this chapter before reading a valuable paper, "Caratteri
rudimentali in ordine all' origine dell' uomo" ('Annuario della Soc. d.
Naturalisti,' Modena, 1867, p. 81), by G. Canestrini, to which paper I am
considerably indebted.  Haeckel has given admirable discussions on this
whole subject, under the title of Dysteleology, in his 'Generelle
Morphologie' and 'Schoepfungsgeschichte.')  Not one of the higher animals
can be named which does not bear some part in a rudimentary condition; and
man forms no exception to the rule.  Rudimentary organs must be
distinguished from those that are nascent; though in some cases the
distinction is not easy.  The former are either absolutely useless, such as
the mammae of male quadrupeds, or the incisor teeth of ruminants which
never cut through the gums; or they are of such slight service to their
present possessors, that we can hardly suppose that they were developed
under the conditions which now exist.  Organs in this latter state are not
strictly rudimentary, but they are tending in this direction.  Nascent
organs, on the other hand, though not fully developed, are of high service
to their possessors, and are capable of further development.  Rudimentary
organs are eminently variable; and this is partly intelligible, as they are
useless, or nearly useless, and consequently are no longer subjected to
natural selection.  They often become wholly suppressed.  When this occurs,
they are nevertheless liable to occasional reappearance through reversion--
a circumstance well worthy of attention.

The chief agents in causing organs to become rudimentary seem to have been
disuse at that period of life when the organ is chiefly used (and this is
generally during maturity), and also inheritance at a corresponding period
of life.  The term "disuse" does not relate merely to the lessened action
of muscles, but includes a diminished flow of blood to a part or organ,
from being subjected to fewer alternations of pressure, or from becoming in
any way less habitually active.  Rudiments, however, may occur in one sex
of those parts which are normally present in the other sex; and such
rudiments, as we shall hereafter see, have often originated in a way
distinct from those here referred to.  In some cases, organs have been
reduced by means of natural selection, from having become injurious to the
species under changed habits of life.  The process of reduction is probably
often aided through the two principles of compensation and economy of
growth; but the later stages of reduction, after disuse has done all that
can fairly be attributed to it, and when the saving to be effected by the
economy of growth would be very small (23.  Some good criticisms on this
subject have been given by Messrs. Murie and Mivart, in 'Transact.
Zoological Society,' 1869, vol. vii. p. 92.), are difficult to understand.
The final and complete suppression of a part, already useless and much
reduced in size, in which case neither compensation nor economy can come
into play, is perhaps intelligible by the aid of the hypothesis of
pangenesis.  But as the whole subject of rudimentary organs has been
discussed and illustrated in my former works (24.  'Variation of Animals
and Plants under Domestication,' vol. ii pp. 317 and 397.  See also 'Origin
of Species,' 5th Edition p. 535.), I need here say no more on this head.

Rudiments of various muscles have been observed in many parts of the human
body (25.  For instance, M. Richard ('Annales des Sciences Nat.,' 3rd
series, Zoolog. 1852, tom. xviii. p. 13) describes and figures rudiments of
what he calls the "muscle pedieux de la main," which he says is sometimes
"infiniment petit."  Another muscle, called "le tibial posterieur," is
generally quite absent in the hand, but appears from time to time in a more
or less rudimentary condition.); and not a few muscles, which are regularly
present in some of the lower animals can occasionally be detected in man in
a greatly reduced condition.  Every one must have noticed the power which
many animals, especially horses, possess of moving or twitching their skin;
and this is effected by the panniculus carnosus.  Remnants of this muscle
in an efficient state are found in various parts of our bodies; for
instance, the muscle on the forehead, by which the eyebrows are raised.
The platysma myoides, which is well developed on the neck, belongs to this
system.  Prof. Turner, of Edinburgh, has occasionally detected, as he
informs me, muscular fasciculi in five different situations, namely in the
axillae, near the scapulae, etc., all of which must be referred to the
system of the panniculus.  He has also shewn (26.  Prof. W. Turner,
'Proceedings of the Royal Society of Edinburgh,' 1866-67, p. 65.) that the
musculus sternalis or sternalis brutorum, which is not an extension of the
rectus abdominalis, but is closely allied to the panniculus, occurred in
the proportion of about three per cent. in upwards of 600 bodies:  he adds,
that this muscle affords "an excellent illustration of the statement that
occasional and rudimentary structures are especially liable to variation in
arrangement."

Some few persons have the power of contracting the superficial muscles on
their scalps; and these muscles are in a variable and partially rudimentary
condition.  M. A. de Candolle has communicated to me a curious instance of
the long-continued persistence or inheritance of this power, as well as of
its unusual development.  He knows a family, in which one member, the
present head of the family, could, when a youth, pitch several heavy books
from his head by the movement of the scalp alone; and he won wagers by
performing this feat.  His father, uncle, grandfather, and his three
children possess the same power to the same unusual degree.  This family
became divided eight generations ago into two branches; so that the head of
the above-mentioned branch is cousin in the seventh degree to the head of
the other branch.  This distant cousin resides in another part of France;
and on being asked whether he possessed the same faculty, immediately
exhibited his power.  This case offers a good illustration how persistent
may be the transmission of an absolutely useless faculty, probably derived
from our remote semi-human progenitors; since many monkeys have, and
frequently use the power, of largely moving their scalps up and down.  (27.
See my 'Expression of the Emotions in Man and Animals,' 1872, p. 144.)

The extrinsic muscles which serve to move the external ear, and the
intrinsic muscles which move the different parts, are in a rudimentary
condition in man, and they all belong to the system of the panniculus; they
are also variable in development, or at least in function.  I have seen one
man who could draw the whole ear forwards; other men can draw it upwards;
another who could draw it backwards (28.  Canestrini quotes Hyrtl.
('Annuario della Soc. dei Naturalisti,' Modena, 1867, p. 97) to the same
effect.); and from what one of these persons told me, it is probable that
most of us, by often touching our ears, and thus directing our attention
towards them, could recover some power of movement by repeated trials.  The
power of erecting and directing the shell of the ears to the various points
of the compass, is no doubt of the highest service to many animals, as they
thus perceive the direction of danger; but I have never heard, on
sufficient evidence, of a man who possessed this power, the one which might
be of use to him.  The whole external shell may be considered a rudiment,
together with the various folds and prominences (helix and anti-helix,
tragus and anti-tragus, etc.) which in the lower animals strengthen and
support the ear when erect, without adding much to its weight.  Some
authors, however, suppose that the cartilage of the shell serves to
transmit vibrations to the acoustic nerve; but Mr. Toynbee (29.  'The
Diseases of the Ear,' by J. Toynbee, F.R.S., 1860, p. 12.  A distinguished
physiologist, Prof. Preyer, informs me that he had lately been
experimenting on the function of the shell of the ear, and has come to
nearly the same conclusion as that given here.), after collecting all the
known evidence on this head, concludes that the external shell is of no
distinct use.  The ears of the chimpanzee and orang are curiously like
those of man, and the proper muscles are likewise but very slightly
developed.  (30.  Prof. A. Macalister, 'Annals and Magazine of Natural
History,' vol. vii. 1871, p. 342.)  I am also assured by the keepers in the
Zoological Gardens that these animals never move or erect their ears; so
that they are in an equally rudimentary condition with those of man, as far
as function is concerned.  Why these animals, as well as the progenitors of
man, should have lost the power of erecting their ears, we cannot say.  It
may be, though I am not satisfied with this view, that owing to their
arboreal habits and great strength they were but little exposed to danger,
and so during a lengthened period moved their ears but little, and thus
gradually lost the power of moving them.  This would be a parallel case
with that of those large and heavy birds, which, from inhabiting oceanic
islands, have not been exposed to the attacks of beasts of prey, and have
consequently lost the power of using their wings for flight.  The inability
to move the ears in man and several apes is, however, partly compensated by
the freedom with which they can move the head in a horizontal plane, so as
to catch sounds from all directions.  It has been asserted that the ear of
man alone possesses a lobule; but "a rudiment of it is found in the
gorilla" (31.  Mr. St. George Mivart, 'Elementary Anatomy,' 1873, p. 396.);
and, as I hear from Prof. Preyer, it is not rarely absent in the negro.

[Fig. 2. Human Ear, modelled and drawn by Mr. Woolner.  The projecting
point is labelled a.]

The celebrated sculptor, Mr. Woolner, informs me of one little peculiarity
in the external ear, which he has often observed both in men and women, and
of which he perceived the full significance.  His attention was first
called to the subject whilst at work on his figure of Puck, to which he had
given pointed ears.  He was thus led to examine the ears of various
monkeys, and subsequently more carefully those of man.  The peculiarity
consists in a little blunt point, projecting from the inwardly folded
margin, or helix.  When present, it is developed at birth, and, according
to Prof. Ludwig Meyer, more frequently in man than in woman.  Mr. Woolner
made an exact model of one such case, and sent me the accompanying drawing.
(Fig. 2).  These points not only project inwards towards the centre of the
ear, but often a little outwards from its plane, so as to be visible when
the head is viewed from directly in front or behind.  They are variable in
size, and somewhat in position, standing either a little higher or lower;
and they sometimes occur on one ear and not on the other.  They are not
confined to mankind, for I observed a case in one of the spider-monkeys
(Ateles beelzebuth) in our Zoological Gardens; and Mr. E. Ray Lankester
informs me of another case in a chimpanzee in the gardens at Hamburg.  The
helix obviously consists of the extreme margin of the ear folded inwards;
and this folding appears to be in some manner connected with the whole
external ear being permanently pressed backwards.  In many monkeys, which
do not stand high in the order, as baboons and some species of macacus (32.
See also some remarks, and the drawings of the ears of the Lemuroidea, in
Messrs. Murie and Mivart's excellent paper in 'Transactions of the
Zoological Society,' vol. vii. 1869, pp. 6 and 90.), the upper portion of
the ear is slightly pointed, and the margin is not at all folded inwards;
but if the margin were to be thus folded, a slight point would necessarily
project inwards towards the centre, and probably a little outwards from the
plane of the ear; and this I believe to be their origin in many cases.  On
the other hand, Prof. L. Meyer, in an able paper recently published (33.
'Ueber das Darwin'sche Spitzohr,' Archiv fur Path. Anat. und Phys., 1871, p.
485.), maintains that the whole case is one of mere variability; and that
the projections are not real ones, but are due to the internal cartilage on
each side of the points not having been fully developed.  I am quite ready
to admit that this is the correct explanation in many instances, as in
those figured by Prof. Meyer, in which there are several minute points, or
the whole margin is sinuous.  I have myself seen, through the kindness of
Dr. L. Down, the ear of a microcephalous idiot, on which there is a
projection on the outside of the helix, and not on the inward folded edge,
so that this point can have no relation to a former apex of the ear.
Nevertheless in some cases, my original view, that the points are vestiges
of the tips of formerly erect and pointed ears, still seems to me probable.
I think so from the frequency of their occurrence, and from the general
correspondence in position with that of the tip of a pointed ear.  In one
case, of which a photograph has been sent me, the projection is so large,
that supposing, in accordance with Prof. Meyer's view, the ear to be made
perfect by the equal development of the cartilage throughout the whole
extent of the margin, it would have covered fully one-third of the whole
ear.  Two cases have been communicated to me, one in North America, and the
other in England, in which the upper margin is not at all folded inwards,
but is pointed, so that it closely resembles the pointed ear of an ordinary
quadruped in outline.  In one of these cases, which was that of a young
child, the father compared the ear with the drawing which I have given (34.
'The Expression of the Emotions,' p. 136.) of the ear of a monkey, the
Cynopithecus niger, and says that their outlines are closely similar.  If,
in these two cases, the margin had been folded inwards in the normal
manner, an inward projection must have been formed.  I may add that in two
other cases the outline still remains somewhat pointed, although the margin
of the upper part of the ear is normally folded inwards--in one of them,
however, very narrowly.  [Fig.3.  Foetus of an Orang(?).  Exact copy of a
photograph, shewing the form of the ear at this early age.]  The following
woodcut (No. 3) is an accurate copy of a photograph of the foetus of an
orang (kindly sent me by Dr. Nitsche), in which it may be seen how
different the pointed outline of the ear is at this period from its adult
condition, when it bears a close general resemblance to that of man.  It is
evident that the folding over of the tip of such an ear, unless it changed
greatly during its further development, would give rise to a point
projecting inwards.  On the whole, it still seems to me probable that the
points in question are in some cases, both in man and apes, vestiges of a
former condition.

The nictitating membrane, or third eyelid, with its accessory muscles and
other structures, is especially well developed in birds, and is of much
functional importance to them, as it can be rapidly drawn across the whole
eye-ball.  It is found in some reptiles and amphibians, and in certain
fishes, as in sharks.  It is fairly well developed in the two lower
divisions of the mammalian series, namely, in the monotremata and
marsupials, and in some few of the higher mammals, as in the walrus.  But
in man, the quadrumana, and most other mammals, it exists, as is admitted
by all anatomists, as a mere rudiment, called the semilunar fold.  (35.
Muller's 'Elements of Physiology,' Eng. translat. 1842, vol. ii. p. 1117.
Owen, 'Anatomy of Vertebrates,' vol. iii. p. 260; ibid. on the Walrus,
'Proceedings of the Zoological Society,' November 8, 1854.  See also R.
Knox, 'Great Artists and Anatomists,' p. 106.  This rudiment apparently is
somewhat larger in Negroes and Australians than in Europeans, see Carl
Vogt, 'Lectures on Man,' Eng. translat. p. 129.)

The sense of smell is of the highest importance to the greater number of
mammals--to some, as the ruminants, in warning them of danger; to others,
as the Carnivora, in finding their prey; to others, again, as the wild
boar, for both purposes combined.  But the sense of smell is of extremely
slight service, if any, even to the dark coloured races of men, in whom it
is much more highly developed than in the white and civilised races.  (36.
The account given by Humboldt of the power of smell possessed by the
natives of South America is well known, and has been confirmed by others.
M. Houzeau ('Etudes sur les Facultes Mentales,' etc., tom. i. 1872, p. 91)
asserts that he repeatedly made experiments, and proved that Negroes and
Indians could recognise persons in the dark by their odour.  Dr. W. Ogle
has made some curious observations on the connection between the power of
smell and the colouring matter of the mucous membrane of the olfactory
region as well as of the skin of the body.  I have, therefore, spoken in
the text of the dark-coloured races having a finer sense of smell than the
white races.  See his paper, 'Medico-Chirurgical Transactions,' London,
vol. liii. 1870, p. 276.)  Nevertheless it does not warn them of danger,
nor guide them to their food; nor does it prevent the Esquimaux from
sleeping in the most fetid atmosphere, nor many savages from eating
half-putrid meat.  In Europeans the power differs greatly in different
individuals, as I am assured by an eminent naturalist who possesses this
sense highly developed, and who has attended to the subject.  Those who
believe in the principle of gradual evolution, will not readily admit that
the sense of smell in its present state was originally acquired by man, as
he now exists.  He inherits the power in an enfeebled and so far
rudimentary condition, from some early progenitor, to whom it was highly
serviceable, and by whom it was continually used.  In those animals which
have this sense highly developed, such as dogs and horses, the recollection
of persons and of places is strongly associated with their odour; and we
can thus perhaps understand how it is, as Dr. Maudsley has truly remarked
(37.  'The Physiology and Pathology of Mind,' 2nd ed. 1868, p. 134.), that
the sense of smell in man "is singularly effective in recalling vividly the
ideas and images of forgotten scenes and places."

Man differs conspicuously from all the other primates in being almost
naked.  But a few short straggling hairs are found over the greater part of
the body in the man, and fine down on that of the woman.  The different
races differ much in hairiness; and in the individuals of the same race the
hairs are highly variable, not only in abundance, but likewise in position:
thus in some Europeans the shoulders are quite naked, whilst in others they
bear thick tufts of hair.  (38.  Eschricht, Ueber die Richtung der Haare am
menschlichen Koerper, Muller's 'Archiv fur Anat. und Phys.' 1837, s. 47.  I
shall often have to refer to this very curious paper.)  There can be little
doubt that the hairs thus scattered over the body are the rudiments of the
uniform hairy coat of the lower animals.  This view is rendered all the
more probable, as it is known that fine, short, and pale-coloured hairs on
the limbs and other parts of the body, occasionally become developed into
"thickset, long, and rather coarse dark hairs," when abnormally nourished
near old-standing inflamed surfaces.  (39.  Paget, 'Lectures on Surgical
Pathology,' 1853, vol. i. p. 71.)

I am informed by Sir James Paget that often several members of a family
have a few hairs in their eyebrows much longer than the others; so that
even this slight peculiarity seems to be inherited.  These hairs, too, seem
to have their representatives; for in the chimpanzee, and in certain
species of Macacus, there are scattered hairs of considerable length rising
from the naked skin above the eyes, and corresponding to our eyebrows;
similar long hairs project from the hairy covering of the superciliary
ridges in some baboons.

The fine wool-like hair, or so-called lanugo, with which the human foetus
during the sixth month is thickly covered, offers a more curious case.  It
is first developed, during the fifth month, on the eyebrows and face, and
especially round the mouth, where it is much longer than that on the head.
A moustache of this kind was observed by Eschricht (40.  Eschricht, ibid.
s. 40, 47.) on a female foetus; but this is not so surprising a
circumstance as it may at first appear, for the two sexes generally
resemble each other in all external characters during an early period of
growth.  The direction and arrangement of the hairs on all parts of the
foetal body are the same as in the adult, but are subject to much
variability.  The whole surface, including even the forehead and ears, is
thus thickly clothed; but it is a significant fact that the palms of the
hands and the soles of the feet are quite naked, like the inferior surfaces
of all four extremities in most of the lower animals.  As this can hardly
be an accidental coincidence, the woolly covering of the foetus probably
represents the first permanent coat of hair in those mammals which are born
hairy.  Three or four cases have been recorded of persons born with their
whole bodies and faces thickly covered with fine long hairs; and this
strange condition is strongly inherited, and is correlated with an abnormal
condition of the teeth.  (41.  See my 'Variation of Animals and Plants
under Domestication,' vol. ii. p. 327.  Prof. Alex. Brandt has recently
sent me an additional case of a father and son, born in Russia, with these
peculiarities.  I have received drawings of both from Paris.)  Prof. Alex.
Brandt informs me that he has compared the hair from the face of a man thus
characterised, aged thirty-five, with the lanugo of a foetus, and finds it
quite similar in texture; therefore, as he remarks, the case may be
attributed to an arrest of development in the hair, together with its
continued growth.  Many delicate children, as I have been assured by a
surgeon to a hospital for children, have their backs covered by rather long
silky hairs; and such cases probably come under the same head.

It appears as if the posterior molar or wisdom-teeth were tending to become
rudimentary in the more civilised races of man.  These teeth are rather
smaller than the other molars, as is likewise the case with the
corresponding teeth in the chimpanzee and orang; and they have only two
separate fangs.  They do not cut through the gums till about the
seventeenth year, and I have been assured that they are much more liable to
decay, and are earlier lost than the other teeth; but this is denied by
some eminent dentists.  They are also much more liable to vary, both in
structure and in the period of their development, than the other teeth.
(42.  Dr. Webb, 'Teeth in Man and the Anthropoid Apes,' as quoted by Dr. C.
Carter Blake in Anthropological Review, July 1867, p. 299.)  In the
Melanian races, on the other hand, the wisdom-teeth are usually furnished
with three separate fangs, and are generally sound; they also differ from
the other molars in size, less than in the Caucasian races. (43.  Owen,
'Anatomy of Vertebrates,' vol. iii. pp. 320, 321, and 325.)  Prof.
Schaaffhausen accounts for this difference between the races by "the
posterior dental portion of the jaw being always shortened" in those that
are civilised (44.  'On the Primitive Form of the Skull,' Eng. translat.,
in 'Anthropological Review,' Oct. 1868, p. 426), and this shortening may, I
presume, be attributed to civilised men habitually feeding on soft, cooked
food, and thus using their jaws less.  I am informed by Mr. Brace that it
is becoming quite a common practice in the United States to remove some of
the molar teeth of children, as the jaw does not grow large enough for the
perfect development of the normal number.  (45.  Prof. Montegazza writes to
me from Florence, that he has lately been studying the last molar teeth in
the different races of man, and has come to the same conclusion as that
given in my text, viz., that in the higher or civilised races they are on
the road towards atrophy or elimination.)

With respect to the alimentary canal, I have met with an account of only a
single rudiment, namely the vermiform appendage of the caecum.  The caecum
is a branch or diverticulum of the intestine, ending in a cul-de-sac, and
is extremely long in many of the lower vegetable-feeding mammals.  In the
marsupial koala it is actually more than thrice as long as the whole body.
(46.  Owen, 'Anatomy of Vertebrates,' vol. iii. pp. 416, 434, 441.)  It is
sometimes produced into a long gradually-tapering point, and is sometimes
constricted in parts.  It appears as if, in consequence of changed diet or
habits, the caecum had become much shortened in various animals, the
vermiform appendage being left as a rudiment of the shortened part.  That
this appendage is a rudiment, we may infer from its small size, and from
the evidence which Prof. Canestrini (47.  'Annuario della Soc. d. Nat.'
Modena, 1867, p. 94.) has collected of its variability in man.  It is
occasionally quite absent, or again is largely developed.  The passage is
sometimes completely closed for half or two-thirds of its length, with the
terminal part consisting of a flattened solid expansion.  In the orang this
appendage is long and convoluted:  in man it arises from the end of the
short caecum, and is commonly from four to five inches in length, being
only about the third of an inch in diameter.  Not only is it useless, but
it is sometimes the cause of death, of which fact I have lately heard two
instances:  this is due to small hard bodies, such as seeds, entering the
passage, and causing inflammation.  (48.  M. C. Martins ("De l'Unite
Organique," in 'Revue des Deux Mondes,' June 15, 1862, p. 16) and Haeckel
('Generelle Morphologie,' B. ii. s. 278), have both remarked on the
singular fact of this rudiment sometimes causing death.)

In some of the lower Quadrumana, in the Lemuridae and Carnivora, as well as
in many marsupials, there is a passage near the lower end of the humerus,
called the supra-condyloid foramen, through which the great nerve of the
fore limb and often the great artery pass.  Now in the humerus of man,
there is generally a trace of this passage, which is sometimes fairly well
developed, being formed by a depending hook-like process of bone, completed
by a band of ligament.  Dr. Struthers (49.  With respect to inheritance,
see Dr. Struthers in the 'Lancet,' Feb. 15, 1873, and another important
paper, ibid. Jan. 24, 1863, p. 83.  Dr. Knox, as I am informed, was the
first anatomist who drew attention to this peculiar structure in man; see
his 'Great Artists and Anatomists,' p. 63.  See also an important memoir on
this process by Dr. Gruber, in the 'Bulletin de l'Acad. Imp. de St.
Petersbourg,' tom. xii. 1867, p. 448.), who has closely attended to the
subject, has now shewn that this peculiarity is sometimes inherited, as it
has occurred in a father, and in no less than four out of his seven
children.  When present, the great nerve invariably passes through it; and
this clearly indicates that it is the homologue and rudiment of the
supra-condyloid foramen of the lower animals.  Prof. Turner estimates, as
he informs me, that it occurs in about one per cent. of recent skeletons.
But if the occasional development of this structure in man is, as seems
probable, due to reversion, it is a return to a very ancient state of
things, because in the higher Quadrumana it is absent.

There is another foramen or perforation in the humerus, occasionally
present in man, which may be called the inter-condyloid.  This occurs, but
not constantly, in various anthropoid and other apes (50.  Mr. St. George
Mivart, 'Transactions Phil. Soc.' 1867, p. 310.), and likewise in many of
the lower animals.  It is remarkable that this perforation seems to have
been present in man much more frequently during ancient times than
recently.  Mr. Busk (51.  "On the Caves of Gibraltar," 'Transactions of the
International Congress of Prehistoric Archaeology,' Third Session, 1869, p.
159.  Prof. Wyman has lately shewn (Fourth Annual Report, Peabody Museum,
1871, p. 20), that this perforation is present in thirty-one per cent. of
some human remains from ancient mounds in the Western United States, and in
Florida.  It frequently occurs in the negro.) has collected the following
evidence on this head:  Prof. Broca "noticed the perforation in four and a
half per cent. of the arm-bones collected in the 'Cimetiere du Sud,' at
Paris; and in the Grotto of Orrony, the contents of which are referred to
the Bronze period, as many as eight humeri out of thirty-two were
perforated; but this extraordinary proportion, he thinks, might be due to
the cavern having been a sort of 'family vault.'  Again, M. Dupont found
thirty per cent. of perforated bones in the caves of the Valley of the
Lesse, belonging to the Reindeer period; whilst M. Leguay, in a sort of
dolmen at Argenteuil, observed twenty-five per cent. to be perforated; and
M. Pruner-Bey found twenty-six per cent. in the same condition in bones
from Vaureal.  Nor should it be left unnoticed that M. Pruner-Bey states
that this condition is common in Guanche skeletons."  It is an interesting
fact that ancient races, in this and several other cases, more frequently
present structures which resemble those of the lower animals than do the
modern.  One chief cause seems to be that the ancient races stand somewhat
nearer in the long line of descent to their remote animal-like progenitors.

In man, the os coccyx, together with certain other vertebrae hereafter to
be described, though functionless as a tail, plainly represent this part in
other vertebrate animals.  At an early embryonic period it is free, and
projects beyond the lower extremities; as may be seen in the drawing (Fig.
1.) of a human embryo.  Even after birth it has been known, in certain rare
and anomalous cases (52.  Quatrefages has lately collected the evidence on
this subject.  'Revue des Cours Scientifiques,' 1867-1868, p. 625.  In 1840
Fleischmann exhibited a human foetus bearing a free tail, which, as is not
always the case, included vertebral bodies; and this tail was critically
examined by the many anatomists present at the meeting of naturalists at
Erlangen (see Marshall in Niederlandischen Archiv fuer Zoologie, December
1871).), to form a small external rudiment of a tail.  The os coccyx is
short, usually including only four vertebrae, all anchylosed together:  and
these are in a rudimentary condition, for they consist, with the exception
of the basal one, of the centrum alone.  (53.  Owen, 'On the Nature of
Limbs,' 1849, p. 114.)  They are furnished with some small muscles; one of
which, as I am informed by Prof. Turner, has been expressly described by
Theile as a rudimentary repetition of the extensor of the tail, a muscle
which is so largely developed in many mammals.

The spinal cord in man extends only as far downwards as the last dorsal or
first lumbar vertebra; but a thread-like structure (the filum terminale)
runs down the axis of the sacral part of the spinal canal, and even along
the back of the coccygeal bones.  The upper part of this filament, as Prof.
Turner informs me, is undoubtedly homologous with the spinal cord; but the
lower part apparently consists merely of the pia mater, or vascular
investing membrane.  Even in this case the os coccyx may be said to possess
a vestige of so important a structure as the spinal cord, though no longer
enclosed within a bony canal.  The following fact, for which I am also
indebted to Prof. Turner, shews how closely the os coccyx corresponds with
the true tail in the lower animals:  Luschka has recently discovered at the
extremity of the coccygeal bones a very peculiar convoluted body, which is
continuous with the middle sacral artery; and this discovery led Krause and
Meyer to examine the tail of a monkey (Macacus), and of a cat, in both of
which they found a similarly convoluted body, though not at the extremity.

The reproductive system offers various rudimentary structures; but these
differ in one important respect from the foregoing cases.  Here we are not
concerned with the vestige of a part which does not belong to the species
in an efficient state, but with a part efficient in the one sex, and
represented in the other by a mere rudiment.  Nevertheless, the occurrence
of such rudiments is as difficult to explain, on the belief of the separate
creation of each species, as in the foregoing cases.  Hereafter I shall
have to recur to these rudiments, and shall shew that their presence
generally depends merely on inheritance, that is, on parts acquired by one
sex having been partially transmitted to the other.  I will in this place
only give some instances of such rudiments.  It is well known that in the
males of all mammals, including man, rudimentary mammae exist.  These in
several instances have become well developed, and have yielded a copious
supply of milk.  Their essential identity in the two sexes is likewise
shewn by their occasional sympathetic enlargement in both during an attack
of the measles.  The vesicula prostatica, which has been observed in many
male mammals, is now universally acknowledged to be the homologue of the
female uterus, together with the connected passage.  It is impossible to
read Leuckart's able description of this organ, and his reasoning, without
admitting the justness of his conclusion.  This is especially clear in the
case of those mammals in which the true female uterus bifurcates, for in
the males of these the vesicula likewise bifurcates.  (54.  Leuckart, in
Todd's 'Cyclopaedia of Anatomy' 1849-52, vol. iv. p. 1415. In man this
organ is only from three to six lines in length, but, like so many other
rudimentary parts, it is variable in development as well as in other
characters.)  Some other rudimentary structures belonging to the
reproductive system might have been here adduced.  (55.  See, on this
subject, Owen, 'Anatomy of Vertebrates,' vol. iii. pp. 675, 676, 706.)

The bearing of the three great classes of facts now given is unmistakeable.
But it would be superfluous fully to recapitulate the line of argument
given in detail in my 'Origin of Species.'  The homological construction of
the whole frame in the members of the same class is intelligible, if we
admit their descent from a common progenitor, together with their
subsequent adaptation to diversified conditions.  On any other view, the
similarity of pattern between the hand of a man or monkey, the foot of a
horse, the flipper of a seal, the wing of a bat, etc., is utterly
inexplicable.  (56.  Prof. Bianconi, in a recently published work,
illustrated by admirable engravings ('La Theorie Darwinienne et la creation
dite independante,' 1874), endeavours to shew that homological structures,
in the above and other cases, can be fully explained on mechanical
principles, in accordance with their uses.  No one has shewn so well, how
admirably such structures are adapted for their final purpose; and this
adaptation can, as I believe, be explained through natural selection.  In
considering the wing of a bat, he brings forward (p. 218) what appears to
me (to use Auguste Comte's words) a mere metaphysical principle, namely,
the preservation "in its integrity of the mammalian nature of the animal."
In only a few cases does he discuss rudiments, and then only those parts
which are partially rudimentary, such as the little hoofs of the pig and
ox, which do not touch the ground; these he shews clearly to be of service
to the animal.  It is unfortunate that he did not consider such cases as
the minute teeth, which never cut through the jaw in the ox, or the mammae
of male quadrupeds, or the wings of certain beetles, existing under the
soldered wing-covers, or the vestiges of the pistil and stamens in various
flowers, and many other such cases.  Although I greatly admire Prof.
Bianconi's work, yet the belief now held by most naturalists seems to me
left unshaken, that homological structures are inexplicable on the
principle of mere adaptation.)  It is no scientific explanation to assert
that they have all been formed on the same ideal plan.  With respect to
development, we can clearly understand, on the principle of variations
supervening at a rather late embryonic period, and being inherited at a
corresponding period, how it is that the embryos of wonderfully different
forms should still retain, more or less perfectly, the structure of their
common progenitor.  No other explanation has ever been given of the
marvellous fact that the embryos of a man, dog, seal, bat, reptile, etc.,
can at first hardly be distinguished from each other.  In order to
understand the existence of rudimentary organs, we have only to suppose
that a former progenitor possessed the parts in question in a perfect
state, and that under changed habits of life they became greatly reduced,
either from simple disuse, or through the natural selection of those
individuals which were least encumbered with a superfluous part, aided by
the other means previously indicated.

Thus we can understand how it has come to pass that man and all other
vertebrate animals have been constructed on the same general model, why
they pass through the same early stages of development, and why they retain
certain rudiments in common.  Consequently we ought frankly to admit their
community of descent:  to take any other view, is to admit that our own
structure, and that of all the animals around us, is a mere snare laid to
entrap our judgment.  This conclusion is greatly strengthened, if we look
to the members of the whole animal series, and consider the evidence
derived from their affinities or classification, their geographical
distribution and geological succession.  It is only our natural prejudice,
and that arrogance which made our forefathers declare that they were
descended from demi-gods, which leads us to demur to this conclusion.  But
the time will before long come, when it will be thought wonderful that
naturalists, who were well acquainted with the comparative structure and
development of man, and other mammals, should have believed that each was
the work of a separate act of creation.


CHAPTER II.

ON THE MANNER OF DEVELOPMENT OF MAN FROM SOME LOWER FORM.

Variability of body and mind in man--Inheritance--Causes of variability--
Laws of variation the same in man as in the lower animals--Direct action of
the conditions of life--Effects of the increased use and disuse of parts--
Arrested development--Reversion--Correlated variation--Rate of increase--
Checks to increase--Natural selection--Man the most dominant animal in the
world--Importance of his corporeal structure--The causes which have led to
his becoming erect--Consequent changes of structure--Decrease in size of
the canine teeth--Increased size and altered shape of the skull--Nakedness
--Absence of a tail--Defenceless condition of man.

It is manifest that man is now subject to much variability.  No two
individuals of the same race are quite alike.  We may compare millions of
faces, and each will be distinct.  There is an equally great amount of
diversity in the proportions and dimensions of the various parts of the
body; the length of the legs being one of the most variable points.  (1.
'Investigations in Military and Anthropological Statistics of American
Soldiers,' by B.A. Gould, 1869, p. 256.)  Although in some quarters of the
world an elongated skull, and in other quarters a short skull prevails, yet
there is great diversity of shape even within the limits of the same race,
as with the aborigines of America and South Australia--the latter a race
"probably as pure and homogeneous in blood, customs, and language as any in
existence"--and even with the inhabitants of so confined an area as the
Sandwich Islands.  (2.  With respect to the "Cranial forms of the American
aborigines," see Dr. Aitken Meigs in 'Proc. Acad. Nat. Sci.' Philadelphia,
May 1868.  On the Australians, see Huxley, in Lyell's 'Antiquity of Man,'
1863, p. 87.  On the Sandwich Islanders, Prof. J. Wyman, 'Observations on
Crania,' Boston, 1868, p. 18.)  An eminent dentist assures me that there is
nearly as much diversity in the teeth as in the features.  The chief
arteries so frequently run in abnormal courses, that it has been found
useful for surgical purposes to calculate from 1040 corpses how often each
course prevails.  (3.  'Anatomy of the Arteries,' by R. Quain.  Preface,
vol. i. 1844.)  The muscles are eminently variable:  thus those of the foot
were found by Prof. Turner (4.  'Transactions of the Royal Society of
Edinburgh,' vol. xxiv. pp. 175, 189.) not to be strictly alike in any two
out of fifty bodies; and in some the deviations were considerable.  He
adds, that the power of performing the appropriate movements must have been
modified in accordance with the several deviations.  Mr. J. Wood has
recorded (5.  'Proceedings Royal Society,' 1867, p. 544; also 1868, pp.
483, 524.  There is a previous paper, 1866, p. 229.) the occurrence of 295
muscular variations in thirty-six subjects, and in another set of the same
number no less than 558 variations, those occurring on both sides of the
body being only reckoned as one.  In the last set, not one body out of the
thirty-six was "found totally wanting in departures from the standard
descriptions of the muscular system given in anatomical text books."  A
single body presented the extraordinary number of twenty-five distinct
abnormalities.  The same muscle sometimes varies in many ways:  thus Prof.
Macalister describes (6.  'Proc. R. Irish Academy,' vol. x. 1868, p. 141.)
no less than twenty distinct variations in the palmaris accessorius.

The famous old anatomist, Wolff (7.  'Act. Acad. St. Petersburg,' 1778,
part ii. p. 217.), insists that the internal viscera are more variable than
the external parts:  Nulla particula est quae non aliter et aliter in aliis
se habeat hominibus.  He has even written a treatise on the choice of
typical examples of the viscera for representation.  A discussion on the
beau-ideal of the liver, lungs, kidneys, etc., as of the human face divine,
sounds strange in our ears.

The variability or diversity of the mental faculties in men of the same
race, not to mention the greater differences between the men of distinct
races, is so notorious that not a word need here be said.  So it is with
the lower animals.  All who have had charge of menageries admit this fact,
and we see it plainly in our dogs and other domestic animals.  Brehm
especially insists that each individual monkey of those which he kept tame
in Africa had its own peculiar disposition and temper:  he mentions one
baboon remarkable for its high intelligence; and the keepers in the
Zoological Gardens pointed out to me a monkey, belonging to the New World
division, equally remarkable for intelligence.  Rengger, also, insists on
the diversity in the various mental characters of the monkeys of the same
species which he kept in Paraguay; and this diversity, as he adds, is
partly innate, and partly the result of the manner in which they have been
treated or educated.  (8.  Brehm, 'Thierleben,' B. i. ss. 58, 87.  Rengger,
'Saeugethiere von Paraguay,' s. 57.)

I have elsewhere (9.  'Variation of Animals and Plants under
Domestication,' vol. ii. chap. xii.) so fully discussed the subject of
Inheritance, that I need here add hardly anything.  A greater number of
facts have been collected with respect to the transmission of the most
trifling, as well as of the most important characters in man, than in any
of the lower animals; though the facts are copious enough with respect to
the latter.  So in regard to mental qualities, their transmission is
manifest in our dogs, horses, and other domestic animals.  Besides special
tastes and habits, general intelligence, courage, bad and good temper,
etc., are certainly transmitted.  With man we see similar facts in almost
every family; and we now know, through the admirable labours of Mr. Galton
(10.  'Hereditary Genius:  an Inquiry into its Laws and Consequences,'
1869.), that genius which implies a wonderfully complex combination of high
faculties, tends to be inherited; and, on the other hand, it is too certain
that insanity and deteriorated mental powers likewise run in families.

With respect to the causes of variability, we are in all cases very
ignorant; but we can see that in man as in the lower animals, they stand in
some relation to the conditions to which each species has been exposed,
during several generations.  Domesticated animals vary more than those in a
state of nature; and this is apparently due to the diversified and changing
nature of the conditions to which they have been subjected.  In this
respect the different races of man resemble domesticated animals, and so do
the individuals of the same race, when inhabiting a very wide area, like
that of America.  We see the influence of diversified conditions in the
more civilised nations; for the members belonging to different grades of
rank, and following different occupations, present a greater range of
character than do the members of barbarous nations.  But the uniformity of
savages has often been exaggerated, and in some cases can hardly be said to
exist.  (11.  Mr. Bates remarks ('The Naturalist on the Amazons,' 1863,
vol. ii p. 159), with respect to the Indians of the same South American
tribe, "no two of them were at all similar in the shape of the head; one
man had an oval visage with fine features, and another was quite Mongolian
in breadth and prominence of cheek, spread of nostrils, and obliquity of
eyes.")  It is, nevertheless, an error to speak of man, even if we look
only to the conditions to which he has been exposed, as "far more
domesticated" (12.  Blumenbach, 'Treatises on Anthropology.' Eng.
translat., 1865, p. 205.) than any other animal.  Some savage races, such
as the Australians, are not exposed to more diversified conditions than are
many species which have a wide range.  In another and much more important
respect, man differs widely from any strictly domesticated animal; for his
breeding has never long been controlled, either by methodical or
unconscious selection.  No race or body of men has been so completely
subjugated by other men, as that certain individuals should be preserved,
and thus unconsciously selected, from somehow excelling in utility to their
masters.  Nor have certain male and female individuals been intentionally
picked out and matched, except in the well-known case of the Prussian
grenadiers; and in this case man obeyed, as might have been expected, the
law of methodical selection; for it is asserted that many tall men were
reared in the villages inhabited by the grenadiers and their tall wives.
In Sparta, also, a form of selection was followed, for it was enacted that
all children should be examined shortly after birth; the well-formed and
vigorous being preserved, the others left to perish.  (13.  Mitford's
'History of Greece,' vol. i. p. 282.  It appears also from a passage in
Xenophon's 'Memorabilia,' B. ii. 4 (to which my attention has been called
by the Rev. J.N. Hoare), that it was a well recognised principle with the
Greeks, that men ought to select their wives with a view to the health and
vigour of their children.  The Grecian poet, Theognis, who lived 550 B.C.,
clearly saw how important selection, if carefully applied, would be for the
improvement of mankind.  He saw, likewise, that wealth often checks the
proper action of sexual selection.  He thus writes:

    "With kine and horses, Kurnus! we proceed
    By reasonable rules, and choose a breed
    For profit and increase, at any price:
    Of a sound stock, without defect or vice.
    But, in the daily matches that we make,
    The price is everything:  for money's sake,
    Men marry:  women are in marriage given
    The churl or ruffian, that in wealth has thriven,
    May match his offspring with the proudest race:
    Thus everything is mix'd, noble and base!
    If then in outward manner, form, and mind,
    You find us a degraded, motley kind,
    Wonder no more, my friend! the cause is plain,
    And to lament the consequence is vain."

(The Works of J. Hookham Frere, vol. ii. 1872, p. 334.))

If we consider all the races of man as forming a single species, his range
is enormous; but some separate races, as the Americans and Polynesians,
have very wide ranges.  It is a well-known law that widely-ranging species
are much more variable than species with restricted ranges; and the
variability of man may with more truth be compared with that of widely-
ranging species, than with that of domesticated animals.

Not only does variability appear to be induced in man and the lower animals
by the same general causes, but in both the same parts of the body are
affected in a closely analogous manner.  This has been proved in such full
detail by Godron and Quatrefages, that I need here only refer to their
works.  (14.  Godron, 'De l'Espece,' 1859, tom. ii. livre 3.  Quatrefages,
'Unite de l'Espece Humaine,' 1861.  Also Lectures on Anthropology, given in
the 'Revue des Cours Scientifiques,' 1866-1868.)  Monstrosities, which
graduate into slight variations, are likewise so similar in man and the
lower animals, that the same classification and the same terms can be used
for both, as has been shewn by Isidore Geoffroy St.-Hilaire.  (15.  'Hist.
Gen. et Part. des Anomalies de l'Organisation,' in three volumes, tom. i.
1832.)  In my work on the variation of domestic animals, I have attempted
to arrange in a rude fashion the laws of variation under the following
heads:--The direct and definite action of changed conditions, as exhibited
by all or nearly all the individuals of the same species, varying in the
same manner under the same circumstances.  The effects of the long-
continued use or disuse of parts.  The cohesion of homologous parts.  The
variability of multiple parts.  Compensation of growth; but of this law I
have found no good instance in the case of man.  The effects of the
mechanical pressure of one part on another; as of the pelvis on the cranium
of the infant in the womb.  Arrests of development, leading to the
diminution or suppression of parts.  The reappearance of long-lost
characters through reversion.  And lastly, correlated variation.  All these
so-called laws apply equally to man and the lower animals; and most of them
even to plants.  It would be superfluous here to discuss all of them (16.
I have fully discussed these laws in my 'Variation of Animals and Plants
under Domestication,' vol. ii. chap. xxii. and xxiii.  M. J.P. Durand has
lately (1868) published a valuable essay, 'De l'Influence des Milieux,'
etc.  He lays much stress, in the case of plants, on the nature of the
soil.);  but several are so important, that they must be treated at
considerable length.

THE DIRECT AND DEFINITE ACTION OF CHANGED CONDITIONS.

This is a most perplexing subject.  It cannot be denied that changed
conditions produce some, and occasionally a considerable effect, on
organisms of all kinds; and it seems at first probable that if sufficient
time were allowed this would be the invariable result.  But I have failed
to obtain clear evidence in favour of this conclusion; and valid reasons
may be urged on the other side, at least as far as the innumerable
structures are concerned, which are adapted for special ends.  There can,
however, be no doubt that changed conditions induce an almost indefinite
amount of fluctuating variability, by which the whole organisation is
rendered in some degree plastic.

In the United States, above 1,000,000 soldiers, who served in the late war,
were measured, and the States in which they were born and reared were
recorded.  (17.  'Investigations in Military and Anthrop. Statistics,'
etc., 1869, by B.A. Gould, pp. 93, 107, 126, 131, 134.)  From this
astonishing number of observations it is proved that local influences of
some kind act directly on stature; and we further learn that "the State
where the physical growth has in great measure taken place, and the State
of birth, which indicates the ancestry, seem to exert a marked influence on
the stature."  For instance, it is established, "that residence in the
Western States, during the years of growth, tends to produce increase of
stature."  On the other hand, it is certain that with sailors, their life
delays growth, as shewn "by the great difference between the statures of
soldiers and sailors at the ages of seventeen and eighteen years."  Mr.
B.A. Gould endeavoured to ascertain the nature of the influences which thus
act on stature; but he arrived only at negative results, namely that they
did not relate to climate, the elevation of the land, soil, nor even "in
any controlling degree" to the abundance or the need of the comforts of
life.  This latter conclusion is directly opposed to that arrived at by
Villerme, from the statistics of the height of the conscripts in different
parts of France.  When we compare the differences in stature between the
Polynesian chiefs and the lower orders within the same islands, or between
the inhabitants of the fertile volcanic and low barren coral islands of the
same ocean (18.  For the Polynesians, see Prichard's 'Physical History of
Mankind,' vol. v. 1847, pp. 145, 283.  Also Godron, 'De l'Espece,' tom. ii.
p. 289.  There is also a remarkable difference in appearance between the
closely-allied Hindoos inhabiting the Upper Ganges and Bengal; see
Elphinstone's 'History of India,' vol. i. p. 324.) or again between the
Fuegians on the eastern and western shores of their country, where the
means of subsistence are very different, it is scarcely possible to avoid
the conclusion that better food and greater comfort do influence stature.
But the preceding statements shew how difficult it is to arrive at any
precise result.  Dr. Beddoe has lately proved that, with the inhabitants of
Britain, residence in towns and certain occupations have a deteriorating
influence on height; and he infers that the result is to a certain extent
inherited, as is likewise the case in the United States.  Dr. Beddoe
further believes that wherever a "race attains its maximum of physical
development, it rises highest in energy and moral vigour."  (19.  'Memoirs,
Anthropological Society,' vol. iii. 1867-69, pp. 561, 565, 567.)

Whether external conditions produce any other direct effect on man is not
known.  It might have been expected that differences of climate would have
had a marked influence, inasmuch as the lungs and kidneys are brought into
activity under a low temperature, and the liver and skin under a high one.
(20.  Dr. Brakenridge, 'Theory of Diathesis,' 'Medical Times,' June 19 and
July 17, 1869.)  It was formerly thought that the colour of the skin and
the character of the hair were determined by light or heat; and although it
can hardly be denied that some effect is thus produced, almost all
observers now agree that the effect has been very small, even after
exposure during many ages.  But this subject will be more properly
discussed when we treat of the different races of mankind.  With our
domestic animals there are grounds for believing that cold and damp
directly affect the growth of the hair; but I have not met with any
evidence on this head in the case of man.

EFFECTS OF THE INCREASED USE AND DISUSE OF PARTS.

It is well known that use strengthens the muscles in the individual, and
complete disuse, or the destruction of the proper nerve, weakens them.
When the eye is destroyed, the optic nerve often becomes atrophied.  When
an artery is tied, the lateral channels increase not only in diameter, but
in the thickness and strength of their coats.  When one kidney ceases to
act from disease, the other increases in size, and does double work.  Bones
increase not only in thickness, but in length, from carrying a greater
weight.  (21.  I have given authorities for these several statements in my
'Variation of Animals and Plants under Domestication,' vol. ii. pp. 297-
300.  Dr. Jaeger, "Ueber das Langenwachsthum der Knochen," 'Jenaeischen
Zeitschrift,' B. v. Heft. i.)  Different occupations, habitually followed,
lead to changed proportions in various parts of the body.  Thus it was
ascertained by the United States Commission (22.  'Investigations,' etc.,
by B.A. Gould, 1869, p. 288.) that the legs of the sailors employed in the
late war were longer by 0.217 of an inch than those of the soldiers, though
the sailors were on an average shorter men; whilst their arms were shorter
by 1.09 of an inch, and therefore, out of proportion, shorter in relation
to their lesser height.  This shortness of the arms is apparently due to
their greater use, and is an unexpected result:  but sailors chiefly use
their arms in pulling, and not in supporting weights.  With sailors, the
girth of the neck and the depth of the instep are greater, whilst the
circumference of the chest, waist, and hips is less, than in soldiers.

Whether the several foregoing modifications would become hereditary, if the
same habits of life were followed during many generations, is not known,
but it is probable.  Rengger (23.  'Saeugethiere von Paraguay,' 1830, s. 4.)
attributes the thin legs and thick arms of the Payaguas Indians to
successive generations having passed nearly their whole lives in canoes,
with their lower extremities motionless.  Other writers have come to a
similar conclusion in analogous cases.  According to Cranz (24.  'History
of Greenland,' Eng. translat., 1767, vol. i. p. 230.), who lived for a long
time with the Esquimaux, "the natives believe that ingenuity and dexterity
in seal-catching (their highest art and virtue) is hereditary; there is
really something in it, for the son of a celebrated seal-catcher will
distinguish himself, though he lost his father in childhood."  But in this
case it is mental aptitude, quite as much as bodily structure, which
appears to be inherited.  It is asserted that the hands of English
labourers are at birth larger than those of the gentry.  (25.
'Intermarriage,' by Alex. Walker, 1838, p. 377.)  From the correlation
which exists, at least in some cases (26.  'The Variation of Animals under
Domestication,' vol. i. p. 173.), between the development of the
extremities and of the jaws, it is possible that in those classes which do
not labour much with their hands and feet, the jaws would be reduced in
size from this cause.  That they are generally smaller in refined and
civilised men than in hard-working men or savages, is certain.  But with
savages, as Mr. Herbert Spencer (27.  'Principles of Biology,' vol. i. p.
455.) has remarked, the greater use of the jaws in chewing coarse, uncooked
food, would act in a direct manner on the masticatory muscles, and on the
bones to which they are attached.  In infants, long before birth, the skin
on the soles of the feet is thicker than on any other part of the body;
(28.  Paget, 'Lectures on Surgical Pathology,' vol. ii, 1853, p. 209.) and
it can hardly be doubted that this is due to the inherited effects of
pressure during a long series of generations.

It is familiar to every one that watchmakers and engravers are liable to be
short-sighted, whilst men living much out of doors, and especially savages,
are generally long-sighted.  (29.  It is a singular and unexpected fact
that sailors are inferior to landsmen in their mean distance of distinct
vision.  Dr. B.A. Gould ('Sanitary Memoirs of the War of the Rebellion,'
1869, p. 530), has proved this to be the case; and he accounts for it by
the ordinary range of vision in sailors being "restricted to the length of
the vessel and the height of the masts.")  Short-sight and long-sight
certainly tend to be inherited.  (30.  'The Variation of Animals under
Domestication,' vol. i. p. 8.)  The inferiority of Europeans, in comparison
with savages, in eyesight and in the other senses, is no doubt the
accumulated and transmitted effect of lessened use during many generations;
for Rengger (31.  'Saeugethiere von Paraguay,' s. 8, 10.  I have had good
opportunities for observing the extraordinary power of eyesight in the
Fuegians.  See also Lawrence ('Lectures on Physiology,' etc., 1822, p. 404)
on this same subject.  M. Giraud-Teulon has recently collected ('Revue des
Cours Scientifiques,' 1870, p. 625) a large and valuable body of evidence
proving that the cause of short-sight, "C'est le travail assidu, de pres.")
states that he has repeatedly observed Europeans, who had been brought up
and spent their whole lives with the wild Indians, who nevertheless did not
equal them in the sharpness of their senses.  The same naturalist observes
that the cavities in the skull for the reception of the several sense-
organs are larger in the American aborigines than in Europeans; and this
probably indicates a corresponding difference in the dimensions of the
organs themselves.  Blumenbach has also remarked on the large size of the
nasal cavities in the skulls of the American aborigines, and connects this
fact with their remarkably acute power of smell.  The Mongolians of the
plains of northern Asia, according to Pallas, have wonderfully perfect
senses; and Prichard believes that the great breadth of their skulls across
the zygomas follows from their highly-developed sense organs.  (32.
Prichard, 'Physical History of Mankind,' on the authority of Blumenbach,
vol. i. 1851, p. 311; for the statement by Pallas, vol. iv. 1844, p. 407.)

The Quechua Indians inhabit the lofty plateaux of Peru; and Alcide
d'Orbigny states (33.  Quoted by Prichard, 'Researches into the Physical
History of Mankind,' vol. v. p. 463.) that, from continually breathing a
highly rarefied atmosphere, they have acquired chests and lungs of
extraordinary dimensions.  The cells, also, of the lungs are larger and
more numerous than in Europeans.  These observations have been doubted, but
Mr. D. Forbes carefully measured many Aymaras, an allied race, living at
the height of between 10,000 and 15,000 feet; and he informs me (34.  Mr.
Forbes' valuable paper is now published in the 'Journal of the Ethnological
Society of London,' new series, vol. ii. 1870, p.193.) that they differ
conspicuously from the men of all other races seen by him in the
circumference and length of their bodies.  In his table of measurements,
the stature of each man is taken at 1000, and the other measurements are
reduced to this standard.  It is here seen that the extended arms of the
Aymaras are shorter than those of Europeans, and much shorter than those of
Negroes.  The legs are likewise shorter; and they present this remarkable
peculiarity, that in every Aymara measured, the femur is actually shorter
than the tibia.  On an average, the length of the femur to that of the
tibia is as 211 to 252; whilst in two Europeans, measured at the same time,
the femora to the tibiae were as 244 to 230; and in three Negroes as 258 to
241.  The humerus is likewise shorter relatively to the forearm.  This
shortening of that part of the limb which is nearest to the body, appears
to be, as suggested to me by Mr. Forbes, a case of compensation in relation
with the greatly increased length of the trunk.  The Aymaras present some
other singular points of structure, for instance, the very small projection
of the heel.

These men are so thoroughly acclimatised to their cold and lofty abode,
that when formerly carried down by the Spaniards to the low eastern plains,
and when now tempted down by high wages to the gold-washings, they suffer a
frightful rate of mortality.  Nevertheless Mr. Forbes found a few pure
families which had survived during two generations:  and he observed that
they still inherited their characteristic peculiarities.  But it was
manifest, even without measurement, that these peculiarities had all
decreased; and on measurement, their bodies were found not to be so much
elongated as those of the men on the high plateau; whilst their femora had
become somewhat lengthened, as had their tibiae, although in a less degree.
The actual measurements may be seen by consulting Mr. Forbes's memoir.
From these observations, there can, I think, be no doubt that residence
during many generations at a great elevation tends, both directly and
indirectly, to induce inherited modifications in the proportions of the
body.  (35.  Dr. Wilckens ('Landwirthschaft.  Wochenblatt,' No. 10, 1869)
has lately published an interesting essay shewing how domestic animals,
which live in mountainous regions, have their frames modified.)

Although man may not have been much modified during the latter stages of
his existence through the increased or decreased use of parts, the facts
now given shew that his liability in this respect has not been lost; and we
positively know that the same law holds good with the lower animals.
Consequently we may infer that when at a remote epoch the progenitors of
man were in a transitional state, and were changing from quadrupeds into
bipeds, natural selection would probably have been greatly aided by the
inherited effects of the increased or diminished use of the different parts
of the body.

ARRESTS OF DEVELOPMENT.

There is a difference between arrested development and arrested growth, for
parts in the former state continue to grow whilst still retaining their
early condition.  Various monstrosities come under this head; and some, as
a cleft palate, are known to be occasionally inherited.  It will suffice
for our purpose to refer to the arrested brain-development of
microcephalous idiots, as described in Vogt's memoir.  (36.  'Memoire sur
les Microcephales,' 1867, pp. 50, 125, 169, 171, 184-198.)  Their skulls
are smaller, and the convolutions of the brain are less complex than in
normal men.  The frontal sinus, or the projection over the eye-brows, is
largely developed, and the jaws are prognathous to an "effrayant" degree;
so that these idiots somewhat resemble the lower types of mankind.  Their
intelligence, and most of their mental faculties, are extremely feeble.
They cannot acquire the power of speech, and are wholly incapable of
prolonged attention, but are much given to imitation.  They are strong and
remarkably active, continually gambolling and jumping about, and making
grimaces.  They often ascend stairs on all-fours; and are curiously fond of
climbing up furniture or trees.  We are thus reminded of the delight shewn
by almost all boys in climbing trees; and this again reminds us how lambs
and kids, originally alpine animals, delight to frisk on any hillock,
however small.  Idiots also resemble the lower animals in some other
respects; thus several cases are recorded of their carefully smelling every
mouthful of food before eating it.  One idiot is described as often using
his mouth in aid of his hands, whilst hunting for lice.  They are often
filthy in their habits, and have no sense of decency; and several cases
have been published of their bodies being remarkably hairy.  (37.  Prof.
Laycock sums up the character of brute-like idiots by calling them
"theroid;" 'Journal of Mental Science,' July 1863.  Dr. Scott ('The Deaf
and Dumb,' 2nd ed. 1870, p. 10) has often observed the imbecile smelling
their food.  See, on this same subject, and on the hairiness of idiots, Dr.
Maudsley, 'Body and Mind,' 1870, pp. 46-51.  Pinel has also given a
striking case of hairiness in an idiot.)

REVERSION.

Many of the cases to be here given, might have been introduced under the
last heading.  When a structure is arrested in its development, but still
continues growing, until it closely resembles a corresponding structure in
some lower and adult member of the same group, it may in one sense be
considered as a case of reversion.  The lower members in a group give us
some idea how the common progenitor was probably constructed; and it is
hardly credible that a complex part, arrested at an early phase of
embryonic development, should go on growing so as ultimately to perform its
proper function, unless it had acquired such power during some earlier
state of existence, when the present exceptional or arrested structure was
normal.  The simple brain of a microcephalous idiot, in as far as it
resembles that of an ape, may in this sense be said to offer a case of
reversion.  (38.  In my 'Variation of Animals under Domestication' (vol.
ii. p. 57), I attributed the not very rare cases of supernumerary mammae in
women to reversion.  I was led to this as a probable conclusion, by the
additional mammae being generally placed symmetrically on the breast; and
more especially from one case, in which a single efficient mamma occurred
in the inguinal region of a woman, the daughter of another woman with
supernumerary mammae.  But I now find (see, for instance, Prof. Preyer,
'Der Kampf um das Dasein,' 1869, s. 45) that mammae erraticae, occur in
other situations, as on the back, in the armpit, and on the thigh; the
mammae in this latter instance having given so much milk that the child was
thus nourished.  The probability that the additional mammae are due to
reversion is thus much weakened; nevertheless, it still seems to me
probable, because two pairs are often found symmetrically on the breast;
and of this I myself have received information in several cases.  It is
well known that some Lemurs normally have two pairs of mammae on the
breast.  Five cases have been recorded of the presence of more than a pair
of mammae (of course rudimentary) in the male sex of mankind; see 'Journal
of Anat. and Physiology,' 1872, p. 56, for a case given by Dr. Handyside,
in which two brothers exhibited this peculiarity; see also a paper by Dr.
Bartels, in 'Reichert's and du Bois-Reymond's Archiv.,' 1872, p. 304.  In
one of the cases alluded to by Dr. Bartels, a man bore five mammae, one
being medial and placed above the navel; Meckel von Hemsbach thinks that
this latter case is illustrated by a medial mamma occurring in certain
Cheiroptera.  On the whole, we may well doubt if additional mammae would
ever have been developed in both sexes of mankind, had not his early
progenitors been provided with more than a single pair.

In the above work (vol. ii. p. 12), I also attributed, though with much
hesitation, the frequent cases of polydactylism in men and various animals
to reversion.  I was partly led to this through Prof. Owen's statement,
that some of the Ichthyopterygia possess more than five digits, and
therefore, as I supposed, had retained a primordial condition; but Prof.
Gegenbaur ('Jenaischen Zeitschrift,' B. v. Heft 3, s. 341), disputes Owen's
conclusion.  On the other hand, according to the opinion lately advanced by
Dr. Gunther, on the paddle of Ceratodus, which is provided with articulated
bony rays on both sides of a central chain of bones, there seems no great
difficulty in admitting that six or more digits on one side, or on both
sides, might reappear through reversion.  I am informed by Dr. Zouteveen
that there is a case on record of a man having twenty-four fingers and
twenty-four toes!  I was chiefly led to the conclusion that the presence of
supernumerary digits might be due to reversion from the fact that such
digits, not only are strongly inherited, but, as I then believed, had the
power of regrowth after amputation, like the normal digits of the lower
vertebrata.  But I have explained in the second edition of my Variation
under Domestication why I now place little reliance on the recorded cases
of such regrowth.  Nevertheless it deserves notice, inasmuch as arrested
development and reversion are intimately related processes; that various
structures in an embryonic or arrested condition, such as a cleft palate,
bifid uterus, etc., are frequently accompanied by polydactylism.  This has
been strongly insisted on by Meckel and Isidore Geoffroy St.-Hilaire.  But
at present it is the safest course to give up altogether the idea that
there is any relation between the development of supernumerary digits and
reversion to some lowly organised progenitor of man.)  There are other
cases which come more strictly under our present head of reversion.
Certain structures, regularly occurring in the lower members of the group
to which man belongs, occasionally make their appearance in him, though not
found in the normal human embryo; or, if normally present in the human
embryo, they become abnormally developed, although in a manner which is
normal in the lower members of the group.  These remarks will be rendered
clearer by the following illustrations.

In various mammals the uterus graduates from a double organ with two
distinct orifices and two passages, as in the marsupials, into a single
organ, which is in no way double except from having a slight internal fold,
as in the higher apes and man.  The rodents exhibit a perfect series of
gradations between these two extreme states.  In all mammals the uterus is
developed from two simple primitive tubes, the inferior portions of which
form the cornua; and it is in the words of Dr. Farre, "by the coalescence
of the two cornua at their lower extremities that the body of the uterus is
formed in man; while in those animals in which no middle portion or body
exists, the cornua remain ununited.  As the development of the uterus
proceeds, the two cornua become gradually shorter, until at length they are
lost, or, as it were, absorbed into the body of the uterus."  The angles of
the uterus are still produced into cornua, even in animals as high up in
the scale as the lower apes and lemurs.

Now in women, anomalous cases are not very infrequent, in which the mature
uterus is furnished with cornua, or is partially divided into two organs;
and such cases, according to Owen, repeat "the grade of concentrative
development," attained by certain rodents.  Here perhaps we have an
instance of a simple arrest of embryonic development, with subsequent
growth and perfect functional development; for either side of the partially
double uterus is capable of performing the proper office of gestation.  In
other and rarer cases, two distinct uterine cavities are formed, each
having its proper orifice and passage.  (39.  See Dr. A. Farre's well-known
article in the 'Cyclopaedia of Anatomy and Physiology,' vol. v. 1859, p.
642.  Owen, 'Anatomy of Vertebrates,' vol. iii. 1868, p. 687.  Professor
Turner, in 'Edinburgh Medical Journal,' February, 1865.)  No such stage is
passed through during the ordinary development of the embryo; and it is
difficult to believe, though perhaps not impossible, that the two simple,
minute, primitive tubes should know how (if such an expression may be used)
to grow into two distinct uteri, each with a well-constructed orifice and
passage, and each furnished with numerous muscles, nerves, glands and
vessels, if they had not formerly passed through a similar course of
development, as in the case of existing marsupials.  No one will pretend
that so perfect a structure as the abnormal double uterus in woman could be
the result of mere chance.  But the principle of reversion, by which a
long-lost structure is called back into existence, might serve as the guide
for its full development, even after the lapse of an enormous interval of
time.

Professor Canestrini, after discussing the foregoing and various analogous
cases, arrives at the same conclusion as that just given.  He adduces
another instance, in the case of the malar bone (40.  'Annuario della Soc.
dei Naturalisti,' Modena, 1867, p. 83.  Prof. Canestrini gives extracts on
this subject from various authorities.  Laurillard remarks, that as he has
found a complete similarity in the form, proportions, and connection of the
two malar bones in several human subjects and in certain apes, he cannot
consider this disposition of the parts as simply accidental.  Another paper
on this same anomaly has been published by Dr. Saviotti in the 'Gazzetta
delle Cliniche,' Turin, 1871, where he says that traces of the division may
be detected in about two per cent. of adult skulls; he also remarks that it
more frequently occurs in prognathous skulls, not of the Aryan race, than
in others.  See also G. Delorenzi on the same subject; 'Tre nuovi casi
d'anomalia dell' osso malare,' Torino, 1872.  Also, E. Morselli, 'Sopra una
rara anomalia dell' osso malare,' Modena, 1872.  Still more recently Gruber
has written a pamphlet on the division of this bone.  I give these
references because a reviewer, without any grounds or scruples, has thrown
doubts on my statements.), which, in some of the Quadrumana and other
mammals, normally consists of two portions.  This is its condition in the
human foetus when two months old; and through arrested development, it
sometimes remains thus in man when adult, more especially in the lower
prognathous races.  Hence Canestrini concludes that some ancient progenitor
of man must have had this bone normally divided into two portions, which
afterwards became fused together.  In man the frontal bone consists of a
single piece, but in the embryo, and in children, and in almost all the
lower mammals, it consists of two pieces separated by a distinct suture.
This suture occasionally persists more or less distinctly in man after
maturity; and more frequently in ancient than in recent crania, especially,
as Canestrini has observed, in those exhumed from the Drift, and belonging
to the brachycephalic type.  Here again he comes to the same conclusion as
in the analogous case of the malar bones.  In this, and other instances
presently to be given, the cause of ancient races approaching the lower
animals in certain characters more frequently than do the modern races,
appears to be, that the latter stand at a somewhat greater distance in the
long line of descent from their early semi-human progenitors.

Various other anomalies in man, more or less analogous to the foregoing,
have been advanced by different authors, as cases of reversion; but these
seem not a little doubtful, for we have to descend extremely low in the
mammalian series, before we find such structures normally present.  (41.  A
whole series of cases is given by Isidore Geoffroy St.-Hilaire, 'Hist. des
Anomalies,' tom, iii, p. 437.  A reviewer ('Journal of Anatomy and
Physiology,' 1871, p. 366) blames me much for not having discussed the
numerous cases, which have been recorded, of various parts arrested in
their development.  He says that, according to my theory, "every transient
condition of an organ, during its development, is not only a means to an
end, but once was an end in itself."  This does not seem to me necessarily
to hold good.  Why should not variations occur during an early period of
development, having no relation to reversion; yet such variations might be
preserved and accumulated, if in any way serviceable, for instance, in
shortening and simplifying the course of development?  And again, why
should not injurious abnormalities, such as atrophied or hypertrophied
parts, which have no relation to a former state of existence, occur at an
early period, as well as during maturity?)

In man, the canine teeth are perfectly efficient instruments for
mastication.  But their true canine character, as Owen (42.  'Anatomy of
Vertebrates,' vol. iii. 1868, p. 323.) remarks, "is indicated by the
conical form of the crown, which terminates in an obtuse point, is convex
outward and flat or sub-concave within, at the base of which surface there
is a feeble prominence.  The conical form is best expressed in the Melanian
races, especially the Australian.  The canine is more deeply implanted, and
by a stronger fang than the incisors."  Nevertheless, this tooth no longer
serves man as a special weapon for tearing his enemies or prey; it may,
therefore, as far as its proper function is concerned, be considered as
rudimentary.  In every large collection of human skulls some may be found,
as Haeckel (43.  'Generelle Morphologie,' 1866, B. ii. s. clv.) observes,
with the canine teeth projecting considerably beyond the others in the same
manner as in the anthropomorphous apes, but in a less degree.  In these
cases, open spaces between the teeth in the one jaw are left for the
reception of the canines of the opposite jaw.  An inter-space of this kind
in a Kaffir skull, figured by Wagner, is surprisingly wide.  (44.  Carl
Vogt's 'Lectures on Man,' Eng. translat., 1864, p. 151.)  Considering how
few are the ancient skulls which have been examined, compared to recent
skulls, it is an interesting fact that in at least three cases the canines
project largely; and in the Naulette jaw they are spoken of as enormous.
(45.  C. Carter Blake, on a jaw from La Naulette, 'Anthropological Review,'
1867, p. 295. Schaaffhausen, ibid. 1868, p. 426.)

Of the anthropomorphous apes the males alone have their canines fully
developed; but in the female gorilla, and in a less degree in the female
orang, these teeth project considerably beyond the others; therefore the
fact, of which I have been assured, that women sometimes have considerably
projecting canines, is no serious objection to the belief that their
occasional great development in man is a case of reversion to an ape-like
progenitor.  He who rejects with scorn the belief that the shape of his own
canines, and their occasional great development in other men, are due to
our early forefathers having been provided with these formidable weapons,
will probably reveal, by sneering, the line of his descent.  For though he
no longer intends, nor has the power, to use these teeth as weapons, he
will unconsciously retract his "snarling muscles" (thus named by Sir C.
Bell) (46.  The Anatomy of Expression, 1844, pp. 110, 131.), so as to
expose them ready for action, like a dog prepared to fight.

Many muscles are occasionally developed in man, which are proper to the
Quadrumana or other mammals.  Professor Vlacovich (47.  Quoted by Prof.
Canestrini in the 'Annuario della Soc. dei Naturalisti,' 1867, p. 90.)
examined forty male subjects, and found a muscle, called by him the ischio-
pubic, in nineteen of them; in three others there was a ligament which
represented this muscle; and in the remaining eighteen no trace of it.  In
only two out of thirty female subjects was this muscle developed on both
sides, but in three others the rudimentary ligament was present.  This
muscle, therefore, appears to be much more common in the male than in the
female sex; and on the belief in the descent of man from some lower form,
the fact is intelligible; for it has been detected in several of the lower
animals, and in all of these it serves exclusively to aid the male in the
act of reproduction.

Mr. J. Wood, in his valuable series of papers (48.  These papers deserve
careful study by any one who desires to learn how frequently our muscles
vary, and in varying come to resemble those of the Quadrumana.  The
following references relate to the few points touched on in my text:
'Proc. Royal Soc.' vol. xiv. 1865, pp. 379-384; vol. xv. 1866, pp. 241,
242; vol. xv. 1867, p. 544; vol. xvi. 1868, p. 524.  I may here add that
Dr. Murie and Mr. St. George Mivart have shewn in their Memoir on the
Lemuroidea ('Transactions, Zoological Society,' vol. vii. 1869, p. 96), how
extraordinarily variable some of the muscles are in these animals, the
lowest members of the Primates.  Gradations, also, in the muscles leading
to structures found in animals still lower in the scale, are numerous in
the Lemuroidea.), has minutely described a vast number of muscular
variations in man, which resemble normal structures in the lower animals.
The muscles which closely resemble those regularly present in our nearest
allies, the Quadrumana, are too numerous to be here even specified.  In a
single male subject, having a strong bodily frame, and well-formed skull,
no less than seven muscular variations were observed, all of which plainly
represented muscles proper to various kinds of apes.  This man, for
instance, had on both sides of his neck a true and powerful "levator
claviculae," such as is found in all kinds of apes, and which is said to
occur in about one out of sixty human subjects.  (49.  See also Prof.
Macalister in 'Proceedings, Royal Irish Academy,' vol. x. 1868, p. 124.)
Again, this man had "a special abductor of the metatarsal bone of the fifth
digit, such as Professor Huxley and Mr. Flower have shewn to exist
uniformly in the higher and lower apes."  I will give only two additional
cases; the acromio-basilar muscle is found in all mammals below man, and
seems to be correlated with a quadrupedal gait, (50.  Mr. Champneys in
'Journal of Anatomy and Physiology,' Nov. 1871, p. 178.) and it occurs in
about one out of sixty human subjects.  In the lower extremities Mr.
Bradley (51.  Ibid. May 1872, p. 421.) found an abductor ossis metatarsi
quinti in both feet of man; this muscle had not up to that time been
recorded in mankind, but is always present in the anthropomorphous apes.
The muscles of the hands and arms--parts which are so eminently
characteristic of man--are extremely liable to vary, so as to resemble the
corresponding muscles in the lower animals.  (52.  Prof. Macalister (ibid.
p. 121) has tabulated his observations, and finds that muscular
abnormalities are most frequent in the fore-arms, secondly, in the face,
thirdly, in the foot, etc.)  Such resemblances are either perfect or
imperfect; yet in the latter case they are manifestly of a transitional
nature.  Certain variations are more common in man, and others in woman,
without our being able to assign any reason.  Mr. Wood, after describing
numerous variations, makes the following pregnant remark.  "Notable
departures from the ordinary type of the muscular structures run in grooves
or directions, which must be taken to indicate some unknown factor, of much
importance to a comprehensive knowledge of general and scientific anatomy."
(53.  The Rev. Dr. Haughton, after giving ('Proc. R. Irish Academy,' June
27, 1864, p. 715) a remarkable case of variation in the human flexor
pollicis longus, adds, "This remarkable example shews that man may
sometimes possess the arrangement of tendons of thumb and fingers
characteristic of the macaque; but whether such a case should be regarded
as a macaque passing upwards into a man, or a man passing downwards into a
macaque, or as a congenital freak of nature, I cannot undertake to say."
It is satisfactory to hear so capable an anatomist, and so embittered an
opponent of evolutionism, admitting even the possibility of either of his
first propositions.  Prof. Macalister has also described ('Proceedings
Royal Irish Academy,' vol. x. 1864, p. 138) variations in the flexor
pollicis longus, remarkable from their relations to the same muscle in the
Quadrumana.)

That this unknown factor is reversion to a former state of existence may be
admitted as in the highest degree probable.  (54.  Since the first edition
of this book appeared, Mr. Wood has published another memoir in the
Philosophical Transactions, 1870, p. 83, on the varieties of the muscles of
the human neck, shoulder, and chest.  He here shews how extremely variable
these muscles are, and how often and how closely the variations resemble
the normal muscles of the lower animals.  He sums up by remarking, "It will
be enough for my purpose if I have succeeded in shewing the more important
forms which, when occurring as varieties in the human subject, tend to
exhibit in a sufficiently marked manner what may be considered as proofs
and examples of the Darwinian principle of reversion, or law of
inheritance, in this department of anatomical science.")  It is quite
incredible that a man should through mere accident abnormally resemble
certain apes in no less than seven of his muscles, if there had been no
genetic connection between them.  On the other hand, if man is descended
from some ape-like creature, no valid reason can be assigned why certain
muscles should not suddenly reappear after an interval of many thousand
generations, in the same manner as with horses, asses, and mules, dark-
coloured stripes suddenly reappear on the legs, and shoulders, after an
interval of hundreds, or more probably of thousands of generations.

These various cases of reversion are so closely related to those of
rudimentary organs given in the first chapter, that many of them might have
been indifferently introduced either there or here.  Thus a human uterus
furnished with cornua may be said to represent, in a rudimentary condition,
the same organ in its normal state in certain mammals.  Some parts which
are rudimentary in man, as the os coccyx in both sexes, and the mammae in
the male sex, are always present; whilst others, such as the supracondyloid
foramen, only occasionally appear, and therefore might have been introduced
under the head of reversion.  These several reversionary structures, as
well as the strictly rudimentary ones, reveal the descent of man from some
lower form in an unmistakable manner.

CORRELATED VARIATION.

In man, as in the lower animals, many structures are so intimately related,
that when one part varies so does another, without our being able, in most
cases, to assign any reason.  We cannot say whether the one part governs
the other, or whether both are governed by some earlier developed part.
Various monstrosities, as I. Geoffroy repeatedly insists, are thus
intimately connected.  Homologous structures are particularly liable to
change together, as we see on the opposite sides of the body, and in the
upper and lower extremities.  Meckel long ago remarked, that when the
muscles of the arm depart from their proper type, they almost always
imitate those of the leg; and so, conversely, with the muscles of the legs.
The organs of sight and hearing, the teeth and hair, the colour of the skin
and of the hair, colour and constitution, are more or less correlated.
(55.  The authorities for these several statements are given in my
'Variation of Animals under Domestication,' vol. ii. pp. 320-335.)
Professor Schaaffhausen first drew attention to the relation apparently
existing between a muscular frame and the strongly-pronounced supra-orbital
ridges, which are so characteristic of the lower races of man.

Besides the variations which can be grouped with more or less probability
under the foregoing heads, there is a large class of variations which may
be provisionally called spontaneous, for to our ignorance they appear to
arise without any exciting cause.  It can, however, be shewn that such
variations, whether consisting of slight individual differences, or of
strongly-marked and abrupt deviations of structure, depend much more on the
constitution of the organism than on the nature of the conditions to which
it has been subjected.  (56.  This whole subject has been discussed in
chap. xxiii. vol. ii. of my 'Variation of Animals and Plants under
Domestication.')

RATE OF INCREASE.

Civilised populations have been known under favourable conditions, as in
the United States, to double their numbers in twenty-five years; and,
according to a calculation, by Euler, this might occur in a little over
twelve years.  (57.  See the ever memorable 'Essay on the Principle of
Population,' by the Rev. T. Malthus, vol. i. 1826. pp. 6, 517.)  At the
former rate, the present population of the United States (thirty millions),
would in 657 years cover the whole terraqueous globe so thickly, that four
men would have to stand on each square yard of surface.  The primary or
fundamental check to the continued increase of man is the difficulty of
gaining subsistence, and of living in comfort.  We may infer that this is
the case from what we see, for instance, in the United States, where
subsistence is easy, and there is plenty of room.  If such means were
suddenly doubled in Great Britain, our number would be quickly doubled.
With civilised nations this primary check acts chiefly by restraining
marriages.  The greater death-rate of infants in the poorest classes is
also very important; as well as the greater mortality, from various
diseases, of the inhabitants of crowded and miserable houses, at all ages.
The effects of severe epidemics and wars are soon counterbalanced, and more
than counterbalanced, in nations placed under favourable conditions.
Emigration also comes in aid as a temporary check, but, with the extremely
poor classes, not to any great extent.

There is reason to suspect, as Malthus has remarked, that the reproductive
power is actually less in barbarous, than in civilised races.  We know
nothing positively on this head, for with savages no census has been taken;
but from the concurrent testimony of missionaries, and of others who have
long resided with such people, it appears that their families are usually
small, and large ones rare.  This may be partly accounted for, as it is
believed, by the women suckling their infants during a long time; but it is
highly probable that savages, who often suffer much hardship, and who do
not obtain so much nutritious food as civilised men, would be actually less
prolific.  I have shewn in a former work (58.  'Variation of Animals and
Plants under Domestication,' vol ii. pp. 111-113, 163.), that all our
domesticated quadrupeds and birds, and all our cultivated plants, are more
fertile than the corresponding species in a state of nature.  It is no
valid objection to this conclusion that animals suddenly supplied with an
excess of food, or when grown very fat; and that most plants on sudden
removal from very poor to very rich soil, are rendered more or less
sterile.  We might, therefore, expect that civilised men, who in one sense
are highly domesticated, would be more prolific than wild men.  It is also
probable that the increased fertility of civilised nations would become, as
with our domestic animals, an inherited character:  it is at least known
that with mankind a tendency to produce twins runs in families. (59.  Mr.
Sedgwick, 'British and Foreign Medico-Chirurgical Review,' July 1863, p.
170.)

Notwithstanding that savages appear to be less prolific than civilised
people, they would no doubt rapidly increase if their numbers were not by
some means rigidly kept down.  The Santali, or hill-tribes of India, have
recently afforded a good illustration of this fact; for, as shewn by Mr.
Hunter (60.  'The Annals of Rural Bengal,' by W.W. Hunter, 1868, p. 259.),
they have increased at an extraordinary rate since vaccination has been
introduced, other pestilences mitigated, and war sternly repressed.  This
increase, however, would not have been possible had not these rude people
spread into the adjoining districts, and worked for hire.  Savages almost
always marry; yet there is some prudential restraint, for they do not
commonly marry at the earliest possible age.  The young men are often
required to shew that they can support a wife; and they generally have
first to earn the price with which to purchase her from her parents.  With
savages the difficulty of obtaining subsistence occasionally limits their
number in a much more direct manner than with civilised people, for all
tribes periodically suffer from severe famines.  At such times savages are
forced to devour much bad food, and their health can hardly fail to be
injured.  Many accounts have been published of their protruding stomachs
and emaciated limbs after and during famines.  They are then, also,
compelled to wander much, and, as I was assured in Australia, their infants
perish in large numbers.  As famines are periodical, depending chiefly on
extreme seasons, all tribes must fluctuate in number.  They cannot steadily
and regularly increase, as there is no artificial increase in the supply of
food.  Savages, when hard pressed, encroach on each other's territories,
and war is the result; but they are indeed almost always at war with their
neighbours.  They are liable to many accidents on land and water in their
search for food; and in some countries they suffer much from the larger
beasts of prey.  Even in India, districts have been depopulated by the
ravages of tigers.

Malthus has discussed these several checks, but he does not lay stress
enough on what is probably the most important of all, namely infanticide,
especially of female infants, and the habit of procuring abortion.  These
practices now prevail in many quarters of the world; and infanticide seems
formerly to have prevailed, as Mr. M'Lennan (61.  'Primitive Marriage,'
1865.) has shewn, on a still more extensive scale.  These practices appear
to have originated in savages recognising the difficulty, or rather the
impossibility of supporting all the infants that are born.  Licentiousness
may also be added to the foregoing checks; but this does not follow from
failing means of subsistence; though there is reason to believe that in
some cases (as in Japan) it has been intentionally encouraged as a means of
keeping down the population.

If we look back to an extremely remote epoch, before man had arrived at the
dignity of manhood, he would have been guided more by instinct and less by
reason than are the lowest savages at the present time.  Our early semi-
human progenitors would not have practised infanticide or polyandry; for
the instincts of the lower animals are never so perverted (62.  A writer in
the 'Spectator' (March 12, 1871, p. 320) comments as follows on this
passage:--"Mr. Darwin finds himself compelled to reintroduce a new doctrine
of the fall of man.  He shews that the instincts of the higher animals are
far nobler than the habits of savage races of men, and he finds himself,
therefore, compelled to re-introduce,--in a form of the substantial
orthodoxy of which he appears to be quite unconscious,--and to introduce as
a scientific hypothesis the doctrine that man's gain of KNOWLEDGE was the
cause of a temporary but long-enduring moral deterioration as indicated by
the many foul customs, especially as to marriage, of savage tribes.  What
does the Jewish tradition of the moral degeneration of man through his
snatching at a knowledge forbidden him by his highest instinct assert
beyond this?") as to lead them regularly to destroy their own offspring, or
to be quite devoid of jealousy.  There would have been no prudential
restraint from marriage, and the sexes would have freely united at an early
age.  Hence the progenitors of man would have tended to increase rapidly;
but checks of some kind, either periodical or constant, must have kept down
their numbers, even more severely than with existing savages.  What the
precise nature of these checks were, we cannot say, any more than with most
other animals.  We know that horses and cattle, which are not extremely
prolific animals, when first turned loose in South America, increased at an
enormous rate.  The elephant, the slowest breeder of all known animals,
would in a few thousand years stock the whole world.  The increase of every
species of monkey must be checked by some means; but not, as Brehm remarks,
by the attacks of beasts of prey.  No one will assume that the actual power
of reproduction in the wild horses and cattle of America, was at first in
any sensible degree increased; or that, as each district became fully
stocked, this same power was diminished.  No doubt, in this case, and in
all others, many checks concur, and different checks under different
circumstances; periodical dearths, depending on unfavourable seasons, being
probably the most important of all.  So it will have been with the early
progenitors of man.

NATURAL SELECTION.

We have now seen that man is variable in body and mind; and that the
variations are induced, either directly or indirectly, by the same general
causes, and obey the same general laws, as with the lower animals.  Man has
spread widely over the face of the earth, and must have been exposed,
during his incessant migrations (63.  See some good remarks to this effect
by W. Stanley Jevons, "A Deduction from Darwin's Theory," 'Nature,' 1869,
p. 231.), to the most diversified conditions.  The inhabitants of Tierra
del Fuego, the Cape of Good Hope, and Tasmania in the one hemisphere, and
of the arctic regions in the other, must have passed through many climates,
and changed their habits many times, before they reached their present
homes.  (64.  Latham, 'Man and his Migrations,' 1851, p. 135.)  The early
progenitors of man must also have tended, like all other animals, to have
increased beyond their means of subsistence; they must, therefore,
occasionally have been exposed to a struggle for existence, and
consequently to the rigid law of natural selection.  Beneficial variations
of all kinds will thus, either occasionally or habitually, have been
preserved and injurious ones eliminated.  I do not refer to strongly-marked
deviations of structure, which occur only at long intervals of time, but to
mere individual differences.  We know, for instance, that the muscles of
our hands and feet, which determine our powers of movement, are liable,
like those of the lower animals, (65.  Messrs. Murie and Mivart in their
'Anatomy of the Lemuroidea' ('Transact. Zoolog. Soc.' vol. vii. 1869, pp.
96-98) say, "some muscles are so irregular in their distribution that they
cannot be well classed in any of the above groups."  These muscles differ
even on the opposite sides of the same individual.) to incessant
variability.  If then the progenitors of man inhabiting any district,
especially one undergoing some change in its conditions, were divided into
two equal bodies, the one half which included all the individuals best
adapted by their powers of movement for gaining subsistence, or for
defending themselves, would on an average survive in greater numbers, and
procreate more offspring than the other and less well endowed half.

Man in the rudest state in which he now exists is the most dominant animal
that has ever appeared on this earth.  He has spread more widely than any
other highly organised form:  and all others have yielded before him.  He
manifestly owes this immense superiority to his intellectual faculties, to
his social habits, which lead him to aid and defend his fellows, and to his
corporeal structure.  The supreme importance of these characters has been
proved by the final arbitrament of the battle for life.  Through his powers
of intellect, articulate language has been evolved; and on this his
wonderful advancement has mainly depended.  As Mr. Chauncey Wright remarks
(66.  Limits of Natural Selection, 'North American Review,' Oct. 1870, p.
295.):  "a psychological analysis of the faculty of language shews, that
even the smallest proficiency in it might require more brain power than the
greatest proficiency in any other direction."  He has invented and is able
to use various weapons, tools, traps, etc., with which he defends himself,
kills or catches prey, and otherwise obtains food.  He has made rafts or
canoes for fishing or crossing over to neighbouring fertile islands.  He
has discovered the art of making fire, by which hard and stringy roots can
be rendered digestible, and poisonous roots or herbs innocuous.  This
discovery of fire, probably the greatest ever made by man, excepting
language, dates from before the dawn of history.  These several inventions,
by which man in the rudest state has become so pre-eminent, are the direct
results of the development of his powers of observation, memory, curiosity,
imagination, and reason.  I cannot, therefore, understand how it is that
Mr. Wallace (67.  'Quarterly Review,' April 1869, p. 392.  This subject is
more fully discussed in Mr. Wallace's 'Contributions to the Theory of
Natural Selection,' 1870, in which all the essays referred to in this work
are re-published.  The 'Essay on Man,' has been ably criticised by Prof.
Claparede, one of the most distinguished zoologists in Europe, in an
article published in the 'Bibliotheque Universelle,' June 1870.  The remark
quoted in my text will surprise every one who has read Mr. Wallace's
celebrated paper on 'The Origin of Human Races Deduced from the Theory of
Natural Selection,' originally published in the 'Anthropological Review,'
May 1864, p. clviii.  I cannot here resist quoting a most just remark by
Sir J. Lubbock ('Prehistoric Times,' 1865, p. 479) in reference to this
paper, namely, that Mr. Wallace, "with characteristic unselfishness,
ascribes it (i.e. the idea of natural selection) unreservedly to Mr.
Darwin, although, as is well known, he struck out the idea independently,
and published it, though not with the same elaboration, at the same time.")
maintains, that "natural selection could only have endowed the savage with
a brain a little superior to that of an ape."

Although the intellectual powers and social habits of man are of paramount
importance to him, we must not underrate the importance of his bodily
structure, to which subject the remainder of this chapter will be devoted;
the development of the intellectual and social or moral faculties being
discussed in a later chapter.

Even to hammer with precision is no easy matter, as every one who has tried
to learn carpentry will admit.  To throw a stone with as true an aim as a
Fuegian in defending himself, or in killing birds, requires the most
consummate perfection in the correlated action of the muscles of the hand,
arm, and shoulder, and, further, a fine sense of touch.  In throwing a
stone or spear, and in many other actions, a man must stand firmly on his
feet; and this again demands the perfect co-adaptation of numerous muscles.
To chip a flint into the rudest tool, or to form a barbed spear or hook
from a bone, demands the use of a perfect hand; for, as a most capable
judge, Mr. Schoolcraft (68.  Quoted by Mr. Lawson Tait in his 'Law of
Natural Selection,' 'Dublin Quarterly Journal of Medical Science,' Feb.
1869.  Dr. Keller is likewise quoted to the same effect.), remarks, the
shaping fragments of stone into knives, lances, or arrow-heads, shews
"extraordinary ability and long practice."  This is to a great extent
proved by the fact that primeval men practised a division of labour; each
man did not manufacture his own flint tools or rude pottery, but certain
individuals appear to have devoted themselves to such work, no doubt
receiving in exchange the produce of the chase.  Archaeologists are
convinced that an enormous interval of time elapsed before our ancestors
thought of grinding chipped flints into smooth tools.  One can hardly
doubt, that a man-like animal who possessed a hand and arm sufficiently
perfect to throw a stone with precision, or to form a flint into a rude
tool, could, with sufficient practice, as far as mechanical skill alone is
concerned, make almost anything which a civilised man can make.  The
structure of the hand in this respect may be compared with that of the
vocal organs, which in the apes are used for uttering various signal-cries,
or, as in one genus, musical cadences; but in man the closely similar vocal
organs have become adapted through the inherited effects of use for the
utterance of articulate language.

Turning now to the nearest allies of men, and therefore to the best
representatives of our early progenitors, we find that the hands of the
Quadrumana are constructed on the same general pattern as our own, but are
far less perfectly adapted for diversified uses.  Their hands do not serve
for locomotion so well as the feet of a dog; as may be seen in such monkeys
as the chimpanzee and orang, which walk on the outer margins of the palms,
or on the knuckles.  (69.  Owen, 'Anatomy of Vertebrates,' vol. iii. p.
71.)  Their hands, however, are admirably adapted for climbing trees.
Monkeys seize thin branches or ropes, with the thumb on one side and the
fingers and palm on the other, in the same manner as we do.  They can thus
also lift rather large objects, such as the neck of a bottle, to their
mouths.  Baboons turn over stones, and scratch up roots with their hands.
They seize nuts, insects, or other small objects with the thumb in
opposition to the fingers, and no doubt they thus extract eggs and young
from the nests of birds.  American monkeys beat the wild oranges on the
branches until the rind is cracked, and then tear it off with the fingers
of the two hands.  In a wild state they break open hard fruits with stones.
Other monkeys open mussel-shells with the two thumbs.  With their fingers
they pull out thorns and burs, and hunt for each other's parasites.  They
roll down stones, or throw them at their enemies:  nevertheless, they are
clumsy in these various actions, and, as I have myself seen, are quite
unable to throw a stone with precision.

It seems to me far from true that because "objects are grasped clumsily" by
monkeys, "a much less specialised organ of prehension" would have served
them (70.  'Quarterly Review,' April 1869, p. 392.) equally well with their
present hands.  On the contrary, I see no reason to doubt that more
perfectly constructed hands would have been an advantage to them, provided
that they were not thus rendered less fitted for climbing trees.  We may
suspect that a hand as perfect as that of man would have been
disadvantageous for climbing; for the most arboreal monkeys in the world,
namely, Ateles in America, Colobus in Africa, and Hylobates in Asia, are
either thumbless, or their toes partially cohere, so that their limbs are
converted into mere grasping hooks.  (71.  In Hylobates syndactylus, as the
name expresses, two of the toes regularly cohere; and this, as Mr. Blyth
informs me, is occasionally the case with the toes of H. agilis, lar, and
leuciscus.  Colobus is strictly arboreal and extraordinarily active (Brehm,
'Thierleben,' B. i. s. 50), but whether a better climber than the species
of the allied genera, I do not know.  It deserves notice that the feet of
the sloths, the most arboreal animals in the world, are wonderfully
hook-like.

As soon as some ancient member in the great series of the Primates came to
be less arboreal, owing to a change in its manner of procuring subsistence,
or to some change in the surrounding conditions, its habitual manner of
progression would have been modified:  and thus it would have been rendered
more strictly quadrupedal or bipedal.  Baboons frequent hilly and rocky
districts, and only from necessity climb high trees (72.  Brehm,
'Thierleben,' B. i. s. 80.); and they have acquired almost the gait of a
dog.  Man alone has become a biped; and we can, I think, partly see how he
has come to assume his erect attitude, which forms one of his most
conspicuous characters.  Man could not have attained his present dominant
position in the world without the use of his hands, which are so admirably
adapted to act in obedience to his will.  Sir C. Bell (73.  'The Hand,'
etc., 'Bridgewater Treatise,' 1833, p. 38.) insists that "the hand supplies
all instruments, and by its correspondence with the intellect gives him
universal dominion."  But the hands and arms could hardly have become
perfect enough to have manufactured weapons, or to have hurled stones and
spears with a true aim, as long as they were habitually used for locomotion
and for supporting the whole weight of the body, or, as before remarked, so
long as they were especially fitted for climbing trees.  Such rough
treatment would also have blunted the sense of touch, on which their
delicate use largely depends.  From these causes alone it would have been
an advantage to man to become a biped; but for many actions it is
indispensable that the arms and whole upper part of the body should be
free; and he must for this end stand firmly on his feet.  To gain this
great advantage, the feet have been rendered flat; and the great toe has
been peculiarly modified, though this has entailed the almost complete loss
of its power of prehension.  It accords with the principle of the division
of physiological labour, prevailing throughout the animal kingdom, that as
the hands became perfected for prehension, the feet should have become
perfected for support and locomotion.  With some savages, however, the foot
has not altogether lost its prehensile power, as shewn by their manner of
climbing trees, and of using them in other ways.  (74.  Haeckel has an
excellent discussion on the steps by which man became a biped:  'Natuerliche
Schoepfungsgeschichte,' 1868, s. 507.  Dr. Buchner ('Conferences sur la
Theorie Darwinienne,' 1869, p. 135) has given good cases of the use of the
foot as a prehensile organ by man; and has also written on the manner of
progression of the higher apes, to which I allude in the following
paragraph:  see also Owen ('Anatomy of Vertebrates,' vol. iii. p. 71) on
this latter subject.)

If it be an advantage to man to stand firmly on his feet and to have his
hands and arms free, of which, from his pre-eminent success in the battle
of life there can be no doubt, then I can see no reason why it should not
have been advantageous to the progenitors of man to have become more and
more erect or bipedal.  They would thus have been better able to defend
themselves with stones or clubs, to attack their prey, or otherwise to
obtain food.  The best built individuals would in the long run have
succeeded best, and have survived in larger numbers.  If the gorilla and a
few allied forms had become extinct, it might have been argued, with great
force and apparent truth, that an animal could not have been gradually
converted from a quadruped into a biped, as all the individuals in an
intermediate condition would have been miserably ill-fitted for
progression.  But we know (and this is well worthy of reflection) that the
anthropomorphous apes are now actually in an intermediate condition; and no
one doubts that they are on the whole well adapted for their conditions of
life.  Thus the gorilla runs with a sidelong shambling gait, but more
commonly progresses by resting on its bent hands.  The long-armed apes
occasionally use their arms like crutches, swinging their bodies forward
between them, and some kinds of Hylobates, without having been taught, can
walk or run upright with tolerable quickness; yet they move awkwardly, and
much less securely than man.  We see, in short, in existing monkeys a
manner of progression intermediate between that of a quadruped and a biped;
but, as an unprejudiced judge (75.  Prof. Broca, La Constitution des
Vertebres caudales; 'La Revue d'Anthropologie,' 1872, p. 26, (separate
copy).) insists, the anthropomorphous apes approach in structure more
nearly to the bipedal than to the quadrupedal type.

As the progenitors of man became more and more erect, with their hands and
arms more and more modified for prehension and other purposes, with their
feet and legs at the same time transformed for firm support and
progression, endless other changes of structure would have become
necessary.  The pelvis would have to be broadened, the spine peculiarly
curved, and the head fixed in an altered position, all which changes have
been attained by man.  Prof. Schaaffhausen (76.  'On the Primitive Form of
the Skull,' translated in 'Anthropological Review,' Oct. 1868, p. 428.
Owen ('Anatomy of Vertebrates,' vol. ii. 1866, p. 551) on the mastoid
processes in the higher apes.) maintains that "the powerful mastoid
processes of the human skull are the result of his erect position;" and
these processes are absent in the orang, chimpanzee, etc., and are smaller
in the gorilla than in man.  Various other structures, which appear
connected with man's erect position, might here have been added.  It is
very difficult to decide how far these correlated modifications are the
result of natural selection, and how far of the inherited effects of the
increased use of certain parts, or of the action of one part on another.
No doubt these means of change often co-operate:  thus when certain
muscles, and the crests of bone to which they are attached, become enlarged
by habitual use, this shews that certain actions are habitually performed
and must be serviceable.  Hence the individuals which performed them best,
would tend to survive in greater numbers.

The free use of the arms and hands, partly the cause and partly the result
of man's erect position, appears to have led in an indirect manner to other
modifications of structure.  The early male forefathers of man were, as
previously stated, probably furnished with great canine teeth; but as they
gradually acquired the habit of using stones, clubs, or other weapons, for
fighting with their enemies or rivals, they would use their jaws and teeth
less and less.  In this case, the jaws, together with the teeth, would
become reduced in size, as we may feel almost sure from innumerable
analogous cases.  In a future chapter we shall meet with a closely parallel
case, in the reduction or complete disappearance of the canine teeth in
male ruminants, apparently in relation with the development of their horns;
and in horses, in relation to their habit of fighting with their incisor
teeth and hoofs.

In the adult male anthropomorphous apes, as Rutimeyer (77.  'Die Grenzen
der Thierwelt, eine Betrachtung zu Darwin's Lehre,' 1868, s. 51.), and
others, have insisted, it is the effect on the skull of the great
development of the jaw-muscles that causes it to differ so greatly in many
respects from that of man, and has given to these animals "a truly
frightful physiognomy."  Therefore, as the jaws and teeth in man's
progenitors gradually become reduced in size, the adult skull would have
come to resemble more and more that of existing man.  As we shall hereafter
see, a great reduction of the canine teeth in the males would almost
certainly affect the teeth of the females through inheritance.

As the various mental faculties gradually developed themselves the brain
would almost certainly become larger.  No one, I presume, doubts that the
large proportion which the size of man's brain bears to his body, compared
to the same proportion in the gorilla or orang, is closely connected with
his higher mental powers.  We meet with closely analogous facts with
insects, for in ants the cerebral ganglia are of extraordinary dimensions,
and in all the Hymenoptera these ganglia are many times larger than in the
less intelligent orders, such as beetles.  (78.  Dujardin, 'Annales des
Sciences Nat.' 3rd series, Zoolog., tom. xiv. 1850, p. 203.  See also Mr.
Lowne, 'Anatomy and Phys. of the Musca vomitoria,' 1870, p. 14.  My son,
Mr. F. Darwin, dissected for me the cerebral ganglia of the Formica rufa.)
On the other hand, no one supposes that the intellect of any two animals or
of any two men can be accurately gauged by the cubic contents of their
skulls.  It is certain that there may be extraordinary mental activity with
an extremely small absolute mass of nervous matter:  thus the wonderfully
diversified instincts, mental powers, and affections of ants are notorious,
yet their cerebral ganglia are not so large as the quarter of a small pin's
head.  Under this point of view, the brain of an ant is one of the most
marvellous atoms of matter in the world, perhaps more so than the brain of
a man.

The belief that there exists in man some close relation between the size of
the brain and the development of the intellectual faculties is supported by
the comparison of the skulls of savage and civilised races, of ancient and
modern people, and by the analogy of the whole vertebrate series.  Dr. J.
Barnard Davis has proved (79.  'Philosophical Transactions,' 1869, p.
513.), by many careful measurements, that the mean internal capacity of the
skull in Europeans is 92.3 cubic inches; in Americans 87.5; in Asiatics
87.1; and in Australians only 81.9 cubic inches.  Professor Broca (80.
'Les Selections,' M. P. Broca, 'Revue d'Anthropologies,' 1873; see also, as
quoted in C. Vogt's 'Lectures on Man,' Engl. translat., 1864, pp. 88, 90.
Prichard, 'Physical History of Mankind,' vol. i. 1838, p. 305.) found that
the nineteenth century skulls from graves in Paris were larger than those
from vaults of the twelfth century, in the proportion of 1484 to 1426; and
that the increased size, as ascertained by measurements, was exclusively in
the frontal part of the skull--the seat of the intellectual faculties.
Prichard is persuaded that the present inhabitants of Britain have "much
more capacious brain-cases" than the ancient inhabitants.  Nevertheless, it
must be admitted that some skulls of very high antiquity, such as the
famous one of Neanderthal, are well developed and capacious.  (81.  In the
interesting article just referred to, Prof. Broca has well remarked, that
in civilised nations, the average capacity of the skull must be lowered by
the preservation of a considerable number of individuals, weak in mind and
body, who would have been promptly eliminated in the savage state.  On the
other hand, with savages, the average includes only the more capable
individuals, who have been able to survive under extremely hard conditions
of life.  Broca thus explains the otherwise inexplicable fact, that the
mean capacity of the skull of the ancient Troglodytes of Lozere is greater
than that of modern Frenchmen.)  With respect to the lower animals, M.E.
Lartet (82.  'Comptes-rendus des Sciences,' etc., June 1, 1868.), by
comparing the crania of tertiary and recent mammals belonging to the same
groups, has come to the remarkable conclusion that the brain is generally
larger and the convolutions are more complex in the more recent forms.  On
the other hand, I have shewn (83.  The 'Variation of Animals and Plants
under Domestication,' vol. i. pp. 124-129.) that the brains of domestic
rabbits are considerably reduced in bulk, in comparison with those of the
wild rabbit or hare; and this may be attributed to their having been
closely confined during many generations, so that they have exerted their
intellect, instincts, senses and voluntary movements but little.

The gradually increasing weight of the brain and skull in man must have
influenced the development of the supporting spinal column, more especially
whilst he was becoming erect.  As this change of position was being brought
about, the internal pressure of the brain will also have influenced the
form of the skull; for many facts shew how easily the skull is thus
affected.  Ethnologists believe that it is modified by the kind of cradle
in which infants sleep.  Habitual spasms of the muscles, and a cicatrix
from a severe burn, have permanently modified the facial bones.  In young
persons whose heads have become fixed either sideways or backwards, owing
to disease, one of the two eyes has changed its position, and the shape of
the skull has been altered apparently by the pressure of the brain in a new
direction.  (84.  Schaaffhausen gives from Blumenbach and Busch, the cases
of the spasms and cicatrix, in 'Anthropological Review,' Oct. 1868, p. 420.
Dr. Jarrold ('Anthropologia,' 1808, pp. 115, 116) adduces from Camper and
from his own observations, cases of the modification of the skull from the
head being fixed in an unnatural position.  He believes that in certain
trades, such as that of a shoemaker, where the head is habitually held
forward, the forehead becomes more rounded and prominent.)  I have shewn
that with long-eared rabbits even so trifling a cause as the lopping
forward of one ear drags forward almost every bone of the skull on that
side; so that the bones on the opposite side no longer strictly correspond.
Lastly, if any animal were to increase or diminish much in general size,
without any change in its mental powers, or if the mental powers were to be
much increased or diminished, without any great change in the size of the
body, the shape of the skull would almost certainly be altered.  I infer
this from my observations on domestic rabbits, some kinds of which have
become very much larger than the wild animal, whilst others have retained
nearly the same size, but in both cases the brain has been much reduced
relatively to the size of the body.  Now I was at first much surprised on
finding that in all these rabbits the skull had become elongated or
dolichocephalic; for instance, of two skulls of nearly equal breadth, the
one from a wild rabbit and the other from a large domestic kind, the former
was 3.15 and the latter 4.3 inches in length.  (85.  'Variation of Animals
and Plants under Domestication,' vol. i. p. 117, on the elongation of the
skull; p. 119, on the effect of the lopping of one ear.)  One of the most
marked distinctions in different races of men is that the skull in some is
elongated, and in others rounded; and here the explanation suggested by the
case of the rabbits may hold good; for Welcker finds that short "men
incline more to brachycephaly, and tall men to dolichocephaly" (86.  Quoted
by Schaaffhausen, in 'Anthropological Review,' Oct. 1868, p. 419.); and
tall men may be compared with the larger and longer-bodied rabbits, all of
which have elongated skulls or are dolichocephalic.

From these several facts we can understand, to a certain extent, the means
by which the great size and more or less rounded form of the skull have
been acquired by man; and these are characters eminently distinctive of him
in comparison with the lower animals.

Another most conspicuous difference between man and the lower animals is
the nakedness of his skin.  Whales and porpoises (Cetacea), dugongs
(Sirenia) and the hippopotamus are naked; and this may be advantageous to
them for gliding through the water; nor would it be injurious to them from
the loss of warmth, as the species, which inhabit the colder regions, are
protected by a thick layer of blubber, serving the same purpose as the fur
of seals and otters.  Elephants and rhinoceroses are almost hairless; and
as certain extinct species, which formerly lived under an Arctic climate,
were covered with long wool or hair, it would almost appear as if the
existing species of both genera had lost their hairy covering from exposure
to heat.  This appears the more probable, as the elephants in India which
live on elevated and cool districts are more hairy (87.  Owen, 'Anatomy of
Vertebrates,' vol. iii. p. 619.) than those on the lowlands.  May we then
infer that man became divested of hair from having aboriginally inhabited
some tropical land?  That the hair is chiefly retained in the male sex on
the chest and face, and in both sexes at the junction of all four limbs
with the trunk, favours this inference--on the assumption that the hair was
lost before man became erect; for the parts which now retain most hair
would then have been most protected from the heat of the sun.  The crown of
the head, however, offers a curious exception, for at all times it must
have been one of the most exposed parts, yet it is thickly clothed with
hair.  The fact, however, that the other members of the order of Primates,
to which man belongs, although inhabiting various hot regions, are well
clothed with hair, generally thickest on the upper surface (88.  Isidore
Geoffroy St.-Hilaire remarks ('Histoire Nat. Generale,' tom. ii. 1859, pp.
215-217) on the head of man being covered with long hair; also on the upper
surfaces of monkeys and of other mammals being more thickly clothed than
the lower surfaces.  This has likewise been observed by various authors.
Prof. P. Gervais ('Histoire Nat. des Mammiferes,' tom. i. 1854, p. 28),
however, states that in the Gorilla the hair is thinner on the back, where
it is partly rubbed off, than on the lower surface.), is opposed to the
supposition that man became naked through the action of the sun.  Mr. Belt
believes (89.  The 'Naturalist in Nicaragua,' 1874, p. 209.  As some
confirmation of Mr. Belt's view, I may quote the following passage from Sir
W. Denison ('Varieties of Vice-Regal Life,' vol. i. 1870, p. 440):  "It is
said to be a practice with the Australians, when the vermin get
troublesome, to singe themselves.") that within the tropics it is an
advantage to man to be destitute of hair, as he is thus enabled to free
himself of the multitude of ticks (acari) and other parasites, with which
he is often infested, and which sometimes cause ulceration.  But whether
this evil is of sufficient magnitude to have led to the denudation of his
body through natural selection, may be doubted, since none of the many
quadrupeds inhabiting the tropics have, as far as I know, acquired any
specialised means of relief.  The view which seems to me the most probable
is that man, or rather primarily woman, became divested of hair for
ornamental purposes, as we shall see under Sexual Selection; and, according
to this belief, it is not surprising that man should differ so greatly in
hairiness from all other Primates, for characters, gained through sexual
selection, often differ to an extraordinary degree in closely related
forms.

According to a popular impression, the absence of a tail is eminently
distinctive of man; but as those apes which come nearest to him are
destitute of this organ, its disappearance does not relate exclusively to
man.  The tail often differs remarkably in length within the same genus:
thus in some species of Macacus it is longer than the whole body, and is
formed of twenty-four vertebrae; in others it consists of a scarcely
visible stump, containing only three or four vertebrae.  In some kinds of
baboons there are twenty-five, whilst in the mandrill there are ten very
small stunted caudal vertebrae, or, according to Cuvier (90.  Mr. St.
George Mivart, 'Proc. Zoolog. Soc.' 1865, pp. 562, 583.  Dr. J.E. Gray,
'Cat. Brit. Mus.:  'Skeletons.'  Owen, 'Anatomy of Vertebrates,' vol. ii.
p. 517.  Isidore Geoffroy, 'Hist. Nat. Gen.' tom. ii. p. 244.), sometimes
only five.  The tail, whether it be long or short, almost always tapers
towards the end; and this, I presume, results from the atrophy of the
terminal muscles, together with their arteries and nerves, through disuse,
leading to the atrophy of the terminal bones.  But no explanation can at
present be given of the great diversity which often occurs in its length.
Here, however, we are more specially concerned with the complete external
disappearance of the tail.  Professor Broca has recently shewn (91.  'Revue
d'Anthropologie,' 1872; 'La Constitution des vertebres caudales.') that the
tail in all quadrupeds consists of two portions, generally separated
abruptly from each other; the basal portion consists of vertebrae, more or
less perfectly channelled and furnished with apophyses like ordinary
vertebrae; whereas those of the terminal portion are not channelled, are
almost smooth, and scarcely resemble true vertebrae.  A tail, though not
externally visible, is really present in man and the anthropomorphous apes,
and is constructed on exactly the same pattern in both.  In the terminal
portion the vertebrae, constituting the os coccyx, are quite rudimentary,
being much reduced in size and number.  In the basal portion, the vertebrae
are likewise few, are united firmly together, and are arrested in
development; but they have been rendered much broader and flatter than the
corresponding vertebrae in the tails of other animals:  they constitute
what Broca calls the accessory sacral vertebrae.  These are of functional
importance by supporting certain internal parts and in other ways; and
their modification is directly connected with the erect or semi-erect
attitude of man and the anthropomorphous apes.  This conclusion is the more
trustworthy, as Broca formerly held a different view, which he has now
abandoned.  The modification, therefore, of the basal caudal vertebrae in
man and the higher apes may have been effected, directly or indirectly,
through natural selection.

But what are we to say about the rudimentary and variable vertebrae of the
terminal portion of the tail, forming the os coccyx?  A notion which has
often been, and will no doubt again be ridiculed, namely, that friction has
had something to do with the disappearance of the external portion of the
tail, is not so ridiculous as it at first appears.  Dr. Anderson (92.
'Proceedings Zoological Society,' 1872, p. 210.) states that the extremely
short tail of Macacus brunneus is formed of eleven vertebrae, including the
imbedded basal ones.  The extremity is tendinous and contains no vertebrae;
this is succeeded by five rudimentary ones, so minute that together they
are only one line and a half in length, and these are permanently bent to
one side in the shape of a hook.  The free part of the tail, only a little
above an inch in length, includes only four more small vertebrae.  This
short tail is carried erect; but about a quarter of its total length is
doubled on to itself to the left; and this terminal part, which includes
the hook-like portion, serves "to fill up the interspace between the upper
divergent portion of the callosities;" so that the animal sits on it, and
thus renders it rough and callous.  Dr. Anderson thus sums up his
observations:  "These facts seem to me to have only one explanation; this
tail, from its short size, is in the monkey's way when it sits down, and
frequently becomes placed under the animal while it is in this attitude;
and from the circumstance that it does not extend beyond the extremity of
the ischial tuberosities, it seems as if the tail originally had been bent
round by the will of the animal, into the interspace between the
callosities, to escape being pressed between them and the ground, and that
in time the curvature became permanent, fitting in of itself when the organ
happens to be sat upon."  Under these circumstances it is not surprising
that the surface of the tail should have been roughened and rendered
callous, and Dr. Murie (93.  'Proceedings Zoological Society,' 1872, p.
786.), who carefully observed this species in the Zoological Gardens, as
well as three other closely allied forms with slightly longer tails, says
that when the animal sits down, the tail "is necessarily thrust to one side
of the buttocks; and whether long or short its root is consequently liable
to be rubbed or chafed."  As we now have evidence that mutilations
occasionally produce an inherited effect (94.  I allude to Dr. Brown-
Sequard's observations on the transmitted effect of an operation causing
epilepsy in guinea-pigs, and likewise more recently on the analogous
effects of cutting the sympathetic nerve in the neck.  I shall hereafter
have occasion to refer to Mr. Salvin's interesting case of the apparently
inherited effects of mot-mots biting off the barbs of their own tail-
feathers.  See also on the general subject 'Variation of Animals and Plants
under Domestication,' vol. ii. pp. 22-24.), it is not very improbable that
in short-tailed monkeys, the projecting part of the tail, being
functionally useless, should after many generations have become rudimentary
and distorted, from being continually rubbed and chafed.  We see the
projecting part in this condition in the Macacus brunneus, and absolutely
aborted in the M. ecaudatus and in several of the higher apes.  Finally,
then, as far as we can judge, the tail has disappeared in man and the
anthropomorphous apes, owing to the terminal portion having been injured by
friction during a long lapse of time; the basal and embedded portion having
been reduced and modified, so as to become suitable to the erect or semi-
erect position.

I have now endeavoured to shew that some of the most distinctive characters
of man have in all probability been acquired, either directly, or more
commonly indirectly, through natural selection.  We should bear in mind
that modifications in structure or constitution which do not serve to adapt
an organism to its habits of life, to the food which it consumes, or
passively to the surrounding conditions, cannot have been thus acquired.
We must not, however, be too confident in deciding what modifications are
of service to each being:  we should remember how little we know about the
use of many parts, or what changes in the blood or tissues may serve to fit
an organism for a new climate or new kinds of food.  Nor must we forget the
principle of correlation, by which, as Isidore Geoffroy has shewn in the
case of man, many strange deviations of structure are tied together.
Independently of correlation, a change in one part often leads, through the
increased or decreased use of other parts, to other changes of a quite
unexpected nature.  It is also well to reflect on such facts, as the
wonderful growth of galls on plants caused by the poison of an insect, and
on the remarkable changes of colour in the plumage of parrots when fed on
certain fishes, or inoculated with the poison of toads (95.  The 'Variation
of Animals and Plants under Domestication,' vol. ii. pp. 280, 282.); for we
can thus see that the fluids of the system, if altered for some special
purpose, might induce other changes.  We should especially bear in mind
that modifications acquired and continually used during past ages for some
useful purpose, would probably become firmly fixed, and might be long
inherited.

Thus a large yet undefined extension may safely be given to the direct and
indirect results of natural selection; but I now admit, after reading the
essay by Nageli on plants, and the remarks by various authors with respect
to animals, more especially those recently made by Professor Broca, that in
the earlier editions of my 'Origin of Species' I perhaps attributed too
much to the action of natural selection or the survival of the fittest.  I
have altered the fifth edition of the 'Origin' so as to confine my remarks
to adaptive changes of structure; but I am convinced, from the light gained
during even the last few years, that very many structures which now appear
to us useless, will hereafter be proved to be useful, and will therefore
come within the range of natural selection.  Nevertheless, I did not
formerly consider sufficiently the existence of structures, which, as far
as we can at present judge, are neither beneficial nor injurious; and this
I believe to be one of the greatest oversights as yet detected in my work.
I may be permitted to say, as some excuse, that I had two distinct objects
in view; firstly, to shew that species had not been separately created, and
secondly, that natural selection had been the chief agent of change, though
largely aided by the inherited effects of habit, and slightly by the direct
action of the surrounding conditions.  I was not, however, able to annul
the influence of my former belief, then almost universal, that each species
had been purposely created; and this led to my tacit assumption that every
detail of structure, excepting rudiments, was of some special, though
unrecognised, service.  Any one with this assumption in his mind would
naturally extend too far the action of natural selection, either during
past or present times.  Some of those who admit the principle of evolution,
but reject natural selection, seem to forget, when criticising my book,
that I had the above two objects in view; hence if I have erred in giving
to natural selection great power, which I am very far from admitting, or in
having exaggerated its power, which is in itself probable, I have at least,
as I hope, done good service in aiding to overthrow the dogma of separate
creations.

It is, as I can now see, probable that all organic beings, including man,
possess peculiarities of structure, which neither are now, nor were
formerly of any service to them, and which, therefore, are of no
physiological importance.  We know not what produces the numberless slight
differences between the individuals of each species, for reversion only
carries the problem a few steps backwards, but each peculiarity must have
had its efficient cause.  If these causes, whatever they may be, were to
act more uniformly and energetically during a lengthened period (and
against this no reason can be assigned), the result would probably be not a
mere slight individual difference, but a well-marked and constant
modification, though one of no physiological importance.  Changed
structures, which are in no way beneficial, cannot be kept uniform through
natural selection, though the injurious will be thus eliminated.
Uniformity of character would, however, naturally follow from the assumed
uniformity of the exciting causes, and likewise from the free intercrossing
of many individuals.  During successive periods, the same organism might in
this manner acquire successive modifications, which would be transmitted in
a nearly uniform state as long as the exciting causes remained the same and
there was free intercrossing.  With respect to the exciting causes we can
only say, as when speaking of so-called spontaneous variations, that they
relate much more closely to the constitution of the varying organism, than
to the nature of the conditions to which it has been subjected.

CONCLUSION.

In this chapter we have seen that as man at the present day is liable, like
every other animal, to multiform individual differences or slight
variations, so no doubt were the early progenitors of man; the variations
being formerly induced by the same general causes, and governed by the same
general and complex laws as at present.  As all animals tend to multiply
beyond their means of subsistence, so it must have been with the
progenitors of man; and this would inevitably lead to a struggle for
existence and to natural selection.  The latter process would be greatly
aided by the inherited effects of the increased use of parts, and these two
processes would incessantly react on each other.  It appears, also, as we
shall hereafter see, that various unimportant characters have been acquired
by man through sexual selection.  An unexplained residuum of change must be
left to the assumed uniform action of those unknown agencies, which
occasionally induce strongly marked and abrupt deviations of structure in
our domestic productions.

Judging from the habits of savages and of the greater number of the
Quadrumana, primeval men, and even their ape-like progenitors, probably
lived in society.  With strictly social animals, natural selection
sometimes acts on the individual, through the preservation of variations
which are beneficial to the community.  A community which includes a large
number of well-endowed individuals increases in number, and is victorious
over other less favoured ones; even although each separate member gains no
advantage over the others of the same community.  Associated insects have
thus acquired many remarkable structures, which are of little or no service
to the individual, such as the pollen-collecting apparatus, or the sting of
the worker-bee, or the great jaws of soldier-ants.  With the higher social
animals, I am not aware that any structure has been modified solely for the
good of the community, though some are of secondary service to it.  For
instance, the horns of ruminants and the great canine teeth of baboons
appear to have been acquired by the males as weapons for sexual strife, but
they are used in defence of the herd or troop.  In regard to certain mental
powers the case, as we shall see in the fifth chapter, is wholly different;
for these faculties have been chiefly, or even exclusively, gained for the
benefit of the community, and the individuals thereof have at the same time
gained an advantage indirectly.

It has often been objected to such views as the foregoing, that man is one
of the most helpless and defenceless creatures in the world; and that
during his early and less well-developed condition, he would have been
still more helpless.  The Duke of Argyll, for instance, insists (96.
'Primeval Man,' 1869, p. 66.) that "the human frame has diverged from the
structure of brutes, in the direction of greater physical helplessness and
weakness.  That is to say, it is a divergence which of all others it is
most impossible to ascribe to mere natural selection."  He adduces the
naked and unprotected state of the body, the absence of great teeth or
claws for defence, the small strength and speed of man, and his slight
power of discovering food or of avoiding danger by smell.  To these
deficiencies there might be added one still more serious, namely, that he
cannot climb quickly, and so escape from enemies.  The loss of hair would
not have been a great injury to the inhabitants of a warm country.  For we
know that the unclothed Fuegians can exist under a wretched climate.  When
we compare the defenceless state of man with that of apes, we must remember
that the great canine teeth with which the latter are provided, are
possessed in their full development by the males alone, and are chiefly
used by them for fighting with their rivals; yet the females, which are not
thus provided, manage to survive.

In regard to bodily size or strength, we do not know whether man is
descended from some small species, like the chimpanzee, or from one as
powerful as the gorilla; and, therefore, we cannot say whether man has
become larger and stronger, or smaller and weaker, than his ancestors.  We
should, however, bear in mind that an animal possessing great size,
strength, and ferocity, and which, like the gorilla, could defend itself
from all enemies, would not perhaps have become social:  and this would
most effectually have checked the acquirement of the higher mental
qualities, such as sympathy and the love of his fellows.  Hence it might
have been an immense advantage to man to have sprung from some
comparatively weak creature.

The small strength and speed of man, his want of natural weapons, etc., are
more than counterbalanced, firstly, by his intellectual powers, through
which he has formed for himself weapons, tools, etc., though still
remaining in a barbarous state, and, secondly, by his social qualities
which lead him to give and receive aid from his fellow-men.  No country in
the world abounds in a greater degree with dangerous beasts than Southern
Africa; no country presents more fearful physical hardships than the Arctic
regions; yet one of the puniest of races, that of the Bushmen, maintains
itself in Southern Africa, as do the dwarfed Esquimaux in the Arctic
regions.  The ancestors of man were, no doubt, inferior in intellect, and
probably in social disposition, to the lowest existing savages; but it is
quite conceivable that they might have existed, or even flourished, if
they had advanced in intellect, whilst gradually losing their brute-like
powers, such as that of climbing trees, etc.  But these ancestors would not
have been exposed to any special danger, even if far more helpless and
defenceless than any existing savages, had they inhabited some warm
continent or large island, such as Australia, New Guinea, or Borneo, which
is now the home of the orang.  And natural selection arising from the
competition of tribe with tribe, in some such large area as one of these,
together with the inherited effects of habit, would, under favourable
conditions, have sufficed to raise man to his present high position in the
organic scale.


CHAPTER III.

COMPARISON OF THE MENTAL POWERS OF MAN AND THE LOWER ANIMALS.

The difference in mental power between the highest ape and the lowest
savage, immense--Certain instincts in common--The emotions--Curiosity--
Imitation--Attention--Memory--Imagination--Reason--Progressive improvement
--Tools and weapons used by animals--Abstraction, Self-consciousness--
Language--Sense of beauty--Belief in God, spiritual agencies,
superstitions.

We have seen in the last two chapters that man bears in his bodily
structure clear traces of his descent from some lower form; but it may be
urged that, as man differs so greatly in his mental power from all other
animals, there must be some error in this conclusion.  No doubt the
difference in this respect is enormous, even if we compare the mind of one
of the lowest savages, who has no words to express any number higher than
four, and who uses hardly any abstract terms for common objects or for the
affections (1.  See the evidence on those points, as given by Lubbock,
'Prehistoric Times,' p. 354, etc.), with that of the most highly organised
ape.  The difference would, no doubt, still remain immense, even if one of
the higher apes had been improved or civilised as much as a dog has been in
comparison with its parent-form, the wolf or jackal.  The Fuegians rank
amongst the lowest barbarians; but I was continually struck with surprise
how closely the three natives on board H.M.S. "Beagle," who had lived some
years in England, and could talk a little English, resembled us in
disposition and in most of our mental faculties.  If no organic being
excepting man had possessed any mental power, or if his powers had been of
a wholly different nature from those of the lower animals, then we should
never have been able to convince ourselves that our high faculties had been
gradually developed.  But it can be shewn that there is no fundamental
difference of this kind.  We must also admit that there is a much wider
interval in mental power between one of the lowest fishes, as a lamprey or
lancelet, and one of the higher apes, than between an ape and man; yet this
interval is filled up by numberless gradations.

Nor is the difference slight in moral disposition between a barbarian, such
as the man described by the old navigator Byron, who dashed his child on
the rocks for dropping a basket of sea-urchins, and a Howard or Clarkson;
and in intellect, between a savage who uses hardly any abstract terms, and
a Newton or Shakspeare.  Differences of this kind between the highest men
of the highest races and the lowest savages, are connected by the finest
gradations.  Therefore it is possible that they might pass and be developed
into each other.

My object in this chapter is to shew that there is no fundamental
difference between man and the higher mammals in their mental faculties.
Each division of the subject might have been extended into a separate
essay, but must here be treated briefly.  As no classification of the
mental powers has been universally accepted, I shall arrange my remarks in
the order most convenient for my purpose; and will select those facts which
have struck me most, with the hope that they may produce some effect on the
reader.

With respect to animals very low in the scale, I shall give some additional
facts under Sexual Selection, shewing that their mental powers are much
higher than might have been expected.  The variability of the faculties in
the individuals of the same species is an important point for us, and some
few illustrations will here be given.  But it would be superfluous to enter
into many details on this head, for I have found on frequent enquiry, that
it is the unanimous opinion of all those who have long attended to animals
of many kinds, including birds, that the individuals differ greatly in
every mental characteristic.  In what manner the mental powers were first
developed in the lowest organisms, is as hopeless an enquiry as how life
itself first originated.  These are problems for the distant future, if
they are ever to be solved by man.

As man possesses the same senses as the lower animals, his fundamental
intuitions must be the same.  Man has also some few instincts in common, as
that of self-preservation, sexual love, the love of the mother for her new-
born offspring, the desire possessed by the latter to suck, and so forth.
But man, perhaps, has somewhat fewer instincts than those possessed by the
animals which come next to him in the series.  The orang in the Eastern
islands, and the chimpanzee in Africa, build platforms on which they sleep;
and, as both species follow the same habit, it might be argued that this
was due to instinct, but we cannot feel sure that it is not the result of
both animals having similar wants, and possessing similar powers of
reasoning.  These apes, as we may assume, avoid the many poisonous fruits
of the tropics, and man has no such knowledge:  but as our domestic
animals, when taken to foreign lands, and when first turned out in the
spring, often eat poisonous herbs, which they afterwards avoid, we cannot
feel sure that the apes do not learn from their own experience or from that
of their parents what fruits to select.  It is, however, certain, as we
shall presently see, that apes have an instinctive dread of serpents, and
probably of other dangerous animals.

The fewness and the comparative simplicity of the instincts in the higher
animals are remarkable in contrast with those of the lower animals.  Cuvier
maintained that instinct and intelligence stand in an inverse ratio to each
other; and some have thought that the intellectual faculties of the higher
animals have been gradually developed from their instincts.  But Pouchet,
in an interesting essay (2.  'L'Instinct chez les Insectes,' 'Revue des
Deux Mondes,' Feb. 1870, p. 690.), has shewn that no such inverse ratio
really exists.  Those insects which possess the most wonderful instincts
are certainly the most intelligent.  In the vertebrate series, the least
intelligent members, namely fishes and amphibians, do not possess complex
instincts; and amongst mammals the animal most remarkable for its
instincts, namely the beaver, is highly intelligent, as will be admitted by
every one who has read Mr. Morgan's excellent work.  (3.  'The American
Beaver and His Works,' 1868.)

Although the first dawnings of intelligence, according to Mr. Herbert
Spencer (4.  'The Principles of Psychology,' 2nd edit., 1870, pp. 418-
443.), have been developed through the multiplication and co-ordination of
reflex actions, and although many of the simpler instincts graduate into
reflex actions, and can hardly be distinguished from them, as in the case
of young animals sucking, yet the more complex instincts seem to have
originated independently of intelligence.  I am, however, very far from
wishing to deny that instinctive actions may lose their fixed and untaught
character, and be replaced by others performed by the aid of the free will.
On the other hand, some intelligent actions, after being performed during
several generations, become converted into instincts and are inherited, as
when birds on oceanic islands learn to avoid man.  These actions may then
be said to be degraded in character, for they are no longer performed
through reason or from experience.  But the greater number of the more
complex instincts appear to have been gained in a wholly different manner,
through the natural selection of variations of simpler instinctive actions.
Such variations appear to arise from the same unknown causes acting on the
cerebral organisation, which induce slight variations or individual
differences in other parts of the body; and these variations, owing to our
ignorance, are often said to arise spontaneously.  We can, I think, come to
no other conclusion with respect to the origin of the more complex
instincts, when we reflect on the marvellous instincts of sterile worker-
ants and bees, which leave no offspring to inherit the effects of
experience and of modified habits.

Although, as we learn from the above-mentioned insects and the beaver, a
high degree of intelligence is certainly compatible with complex instincts,
and although actions, at first learnt voluntarily can soon through habit be
performed with the quickness and certainty of a reflex action, yet it is
not improbable that there is a certain amount of interference between the
development of free intelligence and of instinct,--which latter implies
some inherited modification of the brain.  Little is known about the
functions of the brain, but we can perceive that as the intellectual powers
become highly developed, the various parts of the brain must be connected
by very intricate channels of the freest intercommunication; and as a
consequence each separate part would perhaps tend to be less well fitted to
answer to particular sensations or associations in a definite and
inherited--that is instinctive--manner.  There seems even to exist some
relation between a low degree of intelligence and a strong tendency to the
formation of fixed, though not inherited habits; for as a sagacious
physician remarked to me, persons who are slightly imbecile tend to act in
everything by routine or habit; and they are rendered much happier if this
is encouraged.

I have thought this digression worth giving, because we may easily
underrate the mental powers of the higher animals, and especially of man,
when we compare their actions founded on the memory of past events, on
foresight, reason, and imagination, with exactly similar actions
instinctively performed by the lower animals; in this latter case the
capacity of performing such actions has been gained, step by step, through
the variability of the mental organs and natural selection, without any
conscious intelligence on the part of the animal during each successive
generation.  No doubt, as Mr. Wallace has argued (5.  'Contributions to the
Theory of Natural Selection,' 1870, p. 212.), much of the intelligent work
done by man is due to imitation and not to reason; but there is this great
difference between his actions and many of those performed by the lower
animals, namely, that man cannot, on his first trial, make, for instance, a
stone hatchet or a canoe, through his power of imitation.  He has to learn
his work by practice; a beaver, on the other hand, can make its dam or
canal, and a bird its nest, as well, or nearly as well, and a spider its
wonderful web, quite as well (6.  For the evidence on this head, see Mr. J.
Traherne Moggridge's most interesting work, 'Harvesting Ants and Trap-Door
Spiders,' 1873, pp. 126, 128.), the first time it tries as when old and
experienced.

To return to our immediate subject:  the lower animals, like man,
manifestly feel pleasure and pain, happiness and misery.  Happiness is
never better exhibited than by young animals, such as puppies, kittens,
lambs, etc., when playing together, like our own children.  Even insects
play together, as has been described by that excellent observer, P. Huber
(7.  'Recherches sur les Moeurs des Fourmis,' 1810, p. 173.), who saw ants
chasing and pretending to bite each other, like so many puppies.

The fact that the lower animals are excited by the same emotions as
ourselves is so well established, that it will not be necessary to weary
the reader by many details.  Terror acts in the same manner on them as on
us, causing the muscles to tremble, the heart to palpitate, the sphincters
to be relaxed, and the hair to stand on end.  Suspicion, the offspring of
fear, is eminently characteristic of most wild animals.  It is, I think,
impossible to read the account given by Sir E. Tennent, of the behaviour of
the female elephants, used as decoys, without admitting that they
intentionally practise deceit, and well know what they are about.  Courage
and timidity are extremely variable qualities in the individuals of the
same species, as is plainly seen in our dogs.  Some dogs and horses are
ill-tempered, and easily turn sulky; others are good-tempered; and these
qualities are certainly inherited.  Every one knows how liable animals are
to furious rage, and how plainly they shew it.  Many, and probably true,
anecdotes have been published on the long-delayed and artful revenge of
various animals.  The accurate Rengger, and Brehm (8.  All the following
statements, given on the authority of these two naturalists, are taken from
Rengger's 'Naturgesch. der Saeugethiere von Paraguay,' 1830, s. 41-57, and
from Brehm's 'Thierleben,' B. i. s. 10-87.) state that the American and
African monkeys which they kept tame, certainly revenged themselves.  Sir
Andrew Smith, a zoologist whose scrupulous accuracy was known to many
persons, told me the following story of which he was himself an eye-
witness; at the Cape of Good Hope an officer had often plagued a certain
baboon, and the animal, seeing him approaching one Sunday for parade,
poured water into a hole and hastily made some thick mud, which he
skilfully dashed over the officer as he passed by, to the amusement of many
bystanders.  For long afterwards the baboon rejoiced and triumphed whenever
he saw his victim.

The love of a dog for his master is notorious; as an old writer quaintly
says (9.  Quoted by Dr. Lauder Lindsay, in his 'Physiology of Mind in the
Lower Animals,' 'Journal of Mental Science,' April 1871, p. 38.), "A dog is
the only thing on this earth that luvs you more than he luvs himself."

In the agony of death a dog has been known to caress his master, and every
one has heard of the dog suffering under vivisection, who licked the hand
of the operator; this man, unless the operation was fully justified by an
increase of our knowledge, or unless he had a heart of stone, must have
felt remorse to the last hour of his life.

As Whewell (10.  'Bridgewater Treatise,' p. 263.) has well asked, "who that
reads the touching instances of maternal affection, related so often of the
women of all nations, and of the females of all animals, can doubt that the
principle of action is the same in the two cases?"  We see maternal
affection exhibited in the most trifling details; thus Rengger observed an
American monkey (a Cebus) carefully driving away the flies which plagued
her infant; and Duvaucel saw a Hylobates washing the faces of her young
ones in a stream.  So intense is the grief of female monkeys for the loss
of their young, that it invariably caused the death of certain kinds kept
under confinement by Brehm in N. Africa.  Orphan monkeys were always
adopted and carefully guarded by the other monkeys, both males and females.
One female baboon had so capacious a heart that she not only adopted young
monkeys of other species, but stole young dogs and cats, which she
continually carried about.  Her kindness, however, did not go so far as to
share her food with her adopted offspring, at which Brehm was surprised, as
his monkeys always divided everything quite fairly with their own young
ones.  An adopted kitten scratched this affectionate baboon, who certainly
had a fine intellect, for she was much astonished at being scratched, and
immediately examined the kitten's feet, and without more ado bit off the
claws. (11.  A critic, without any grounds ('Quarterly Review,' July 1871,
p. 72), disputes the possibility of this act as described by Brehm, for the
sake of discrediting my work.  Therefore I tried, and found that I could
readily seize with my own teeth the sharp little claws of a kitten nearly
five weeks old.)  In the Zoological Gardens, I heard from the keeper that
an old baboon (C. chacma) had adopted a Rhesus monkey; but when a young
drill and mandrill were placed in the cage, she seemed to perceive that
these monkeys, though distinct species, were her nearer relatives, for she
at once rejected the Rhesus and adopted both of them.  The young Rhesus, as
I saw, was greatly discontented at being thus rejected, and it would, like
a naughty child, annoy and attack the young drill and mandrill whenever it
could do so with safety; this conduct exciting great indignation in the old
baboon.  Monkeys will also, according to Brehm, defend their master when
attacked by any one, as well as dogs to whom they are attached, from the
attacks of other dogs.  But we here trench on the subjects of sympathy and
fidelity, to which I shall recur.  Some of Brehm's monkeys took much
delight in teasing a certain old dog whom they disliked, as well as other
animals, in various ingenious ways.

Most of the more complex emotions are common to the higher animals and
ourselves.  Every one has seen how jealous a dog is of his master's
affection, if lavished on any other creature; and I have observed the same
fact with monkeys.  This shews that animals not only love, but have desire
to be loved.  Animals manifestly feel emulation.  They love approbation or
praise; and a dog carrying a basket for his master exhibits in a high
degree self-complacency or pride.  There can, I think, be no doubt that a
dog feels shame, as distinct from fear, and something very like modesty
when begging too often for food.  A great dog scorns the snarling of a
little dog, and this may be called magnanimity.  Several observers have
stated that monkeys certainly dislike being laughed at; and they sometimes
invent imaginary offences.  In the Zoological Gardens I saw a baboon who
always got into a furious rage when his keeper took out a letter or book
and read it aloud to him; and his rage was so violent that, as I witnessed
on one occasion, he bit his own leg till the blood flowed.  Dogs shew what
may be fairly called a sense of humour, as distinct from mere play; if a
bit of stick or other such object be thrown to one, he will often carry it
away for a short distance; and then squatting down with it on the ground
close before him, will wait until his master comes quite close to take it
away.  The dog will then seize it and rush away in triumph, repeating the
same manoeuvre, and evidently enjoying the practical joke.

We will now turn to the more intellectual emotions and faculties, which are
very important, as forming the basis for the development of the higher
mental powers.  Animals manifestly enjoy excitement, and suffer from ennui,
as may be seen with dogs, and, according to Rengger, with monkeys.  All
animals feel WONDER, and many exhibit CURIOSITY.  They sometimes suffer
from this latter quality, as when the hunter plays antics and thus attracts
them; I have witnessed this with deer, and so it is with the wary chamois,
and with some kinds of wild-ducks.  Brehm gives a curious account of the
instinctive dread, which his monkeys exhibited, for snakes; but their
curiosity was so great that they could not desist from occasionally
satiating their horror in a most human fashion, by lifting up the lid of
the box in which the snakes were kept.  I was so much surprised at his
account, that I took a stuffed and coiled-up snake into the monkey-house at
the Zoological Gardens, and the excitement thus caused was one of the most
curious spectacles which I ever beheld.  Three species of Cercopithecus
were the most alarmed; they dashed about their cages, and uttered sharp
signal cries of danger, which were understood by the other monkeys.  A few
young monkeys and one old Anubis baboon alone took no notice of the snake.
I then placed the stuffed specimen on the ground in one of the larger
compartments.  After a time all the monkeys collected round it in a large
circle, and staring intently, presented a most ludicrous appearance.  They
became extremely nervous; so that when a wooden ball, with which they were
familiar as a plaything, was accidentally moved in the straw, under which
it was partly hidden, they all instantly started away.  These monkeys
behaved very differently when a dead fish, a mouse (12.  I have given a
short account of their behaviour on this occasion in my 'Expression of the
Emotions in Man and Animals,' p. 43.), a living turtle, and other new
objects were placed in their cages; for though at first frightened, they
soon approached, handled and examined them.  I then placed a live snake in
a paper bag, with the mouth loosely closed, in one of the larger
compartments.  One of the monkeys immediately approached, cautiously opened
the bag a little, peeped in, and instantly dashed away.  Then I witnessed
what Brehm has described, for monkey after monkey, with head raised high
and turned on one side, could not resist taking a momentary peep into the
upright bag, at the dreadful object lying quietly at the bottom.  It would
almost appear as if monkeys had some notion of zoological affinities, for
those kept by Brehm exhibited a strange, though mistaken, instinctive dread
of innocent lizards and frogs.  An orang, also, has been known to be much
alarmed at the first sight of a turtle.  (13.  W.C.L. Martin, 'Natural
History of Mammalia,' 1841, p. 405.)

The principle of IMITATION is strong in man, and especially, as I have
myself observed, with savages.  In certain morbid states of the brain this
tendency is exaggerated to an extraordinary degree:  some hemiplegic
patients and others, at the commencement of inflammatory softening of the
brain, unconsciously imitate every word which is uttered, whether in their
own or in a foreign language, and every gesture or action which is
performed near them.  (14.  Dr. Bateman, 'On Aphasia,' 1870, p. 110.)
Desor (15.  Quoted by Vogt, 'Memoire sur les Microcephales,' 1867, p. 168.)
has remarked that no animal voluntarily imitates an action performed by
man, until in the ascending scale we come to monkeys, which are well known
to be ridiculous mockers.  Animals, however, sometimes imitate each other's
actions:  thus two species of wolves, which had been reared by dogs,
learned to bark, as does sometimes the jackal (16.  The 'Variation of
Animals and Plants under Domestication,' vol. i. p. 27.), but whether this
can be called voluntary imitation is another question.  Birds imitate the
songs of their parents, and sometimes of other birds; and parrots are
notorious imitators of any sound which they often hear.  Dureau de la Malle
gives an account (17.  'Annales des Sciences Nat.' (1st Series), tom. xxii.
p. 397.) of a dog reared by a cat, who learnt to imitate the well-known
action of a cat licking her paws, and thus washing her ears and face; this
was also witnessed by the celebrated naturalist Audouin.  I have received
several confirmatory accounts; in one of these, a dog had not been suckled
by a cat, but had been brought up with one, together with kittens, and had
thus acquired the above habit, which he ever afterwards practised during
his life of thirteen years.  Dureau de la Malle's dog likewise learnt from
the kittens to play with a ball by rolling it about with his fore paws, and
springing on it.  A correspondent assures me that a cat in his house used
to put her paws into jugs of milk having too narrow a mouth for her head.
A kitten of this cat soon learned the same trick, and practised it ever
afterwards, whenever there was an opportunity.

The parents of many animals, trusting to the principle of imitation in
their young, and more especially to their instinctive or inherited
tendencies, may be said to educate them.  We see this when a cat brings a
live mouse to her kittens; and Dureau de la Malle has given a curious
account (in the paper above quoted) of his observations on hawks which
taught their young dexterity, as well as judgment of distances, by first
dropping through the air dead mice and sparrows, which the young generally
failed to catch, and then bringing them live birds and letting them loose.

Hardly any faculty is more important for the intellectual progress of man
than ATTENTION.  Animals clearly manifest this power, as when a cat watches
by a hole and prepares to spring on its prey.  Wild animals sometimes
become so absorbed when thus engaged, that they may be easily approached.
Mr. Bartlett has given me a curious proof how variable this faculty is in
monkeys.  A man who trains monkeys to act in plays, used to purchase common
kinds from the Zoological Society at the price of five pounds for each; but
he offered to give double the price, if he might keep three or four of them
for a few days, in order to select one.  When asked how he could possibly
learn so soon, whether a particular monkey would turn out a good actor, he
answered that it all depended on their power of attention.  If when he was
talking and explaining anything to a monkey, its attention was easily
distracted, as by a fly on the wall or other trifling object, the case was
hopeless.  If he tried by punishment to make an inattentive monkey act, it
turned sulky.  On the other hand, a monkey which carefully attended to him
could always be trained.

It is almost superfluous to state that animals have excellent MEMORIES for
persons and places.  A baboon at the Cape of Good Hope, as I have been
informed by Sir Andrew Smith, recognised him with joy after an absence of
nine months.  I had a dog who was savage and averse to all strangers, and I
purposely tried his memory after an absence of five years and two days.  I
went near the stable where he lived, and shouted to him in my old manner;
he shewed no joy, but instantly followed me out walking, and obeyed me,
exactly as if I had parted with him only half an hour before.  A train of
old associations, dormant during five years, had thus been instantaneously
awakened in his mind.  Even ants, as P. Huber (18.  'Les Moeurs des
Fourmis,' 1810, p. 150.) has clearly shewn, recognised their fellow-ants
belonging to the same community after a separation of four months.  Animals
can certainly by some means judge of the intervals of time between
recurrent events.

The IMAGINATION is one of the highest prerogatives of man.  By this faculty
he unites former images and ideas, independently of the will, and thus
creates brilliant and novel results.  A poet, as Jean Paul Richter remarks
(19.  Quoted in Dr. Maudsley's 'Physiology and Pathology of Mind,' 1868,
pp. 19, 220.), "who must reflect whether he shall make a character say yes
or no--to the devil with him; he is only a stupid corpse."  Dreaming gives
us the best notion of this power; as Jean Paul again says, "The dream is an
involuntary art of poetry."  The value of the products of our imagination
depends of course on the number, accuracy, and clearness of our
impressions, on our judgment and taste in selecting or rejecting the
involuntary combinations, and to a certain extent on our power of
voluntarily combining them.  As dogs, cats, horses, and probably all the
higher animals, even birds (20.  Dr. Jerdon, 'Birds of India,' vol. i.
1862, p. xxi.  Houzeau says that his parokeets and canary-birds dreamt:
'Etudes sur les Facultes Mentales des Animaux,' tom. ii. p. 136.) have
vivid dreams, and this is shewn by their movements and the sounds uttered,
we must admit that they possess some power of imagination.  There must be
something special, which causes dogs to howl in the night, and especially
during moonlight, in that remarkable and melancholy manner called baying.
All dogs do not do so; and, according to Houzeau (21.  ibid. 1872, tom. ii.
p. 181.), they do not then look at the moon, but at some fixed point near
the horizon.  Houzeau thinks that their imaginations are disturbed by the
vague outlines of the surrounding objects, and conjure up before them
fantastic images:  if this be so, their feelings may almost be called
superstitious.

Of all the faculties of the human mind, it will, I presume, be admitted
that REASON stands at the summit.  Only a few persons now dispute that
animals possess some power of reasoning.  Animals may constantly be seen to
pause, deliberate, and resolve.  It is a significant fact, that the more
the habits of any particular animal are studied by a naturalist, the more
he attributes to reason and the less to unlearnt instincts.  (22.  Mr. L.H.
Morgan's work on 'The American Beaver,' 1868, offers a good illustration of
this remark.  I cannot help thinking, however, that he goes too far in
underrating the power of instinct.)  In future chapters we shall see that
some animals extremely low in the scale apparently display a certain amount
of reason.  No doubt it is often difficult to distinguish between the power
of reason and that of instinct.  For instance, Dr. Hayes, in his work on
'The Open Polar Sea,' repeatedly remarks that his dogs, instead of
continuing to draw the sledges in a compact body, diverged and separated
when they came to thin ice, so that their weight might be more evenly
distributed.  This was often the first warning which the travellers
received that the ice was becoming thin and dangerous.  Now, did the dogs
act thus from the experience of each individual, or from the example of the
older and wiser dogs, or from an inherited habit, that is from instinct?
This instinct, may possibly have arisen since the time, long ago, when dogs
were first employed by the natives in drawing their sledges; or the Arctic
wolves, the parent-stock of the Esquimaux dog, may have acquired an
instinct impelling them not to attack their prey in a close pack, when on
thin ice.

We can only judge by the circumstances under which actions are performed,
whether they are due to instinct, or to reason, or to the mere association
of ideas:  this latter principle, however, is intimately connected with
reason.  A curious case has been given by Prof. Mobius (23.  'Die
Bewegungen der Thiere,' etc., 1873, p. 11.), of a pike, separated by a
plate of glass from an adjoining aquarium stocked with fish, and who often
dashed himself with such violence against the glass in trying to catch the
other fishes, that he was sometimes completely stunned.  The pike went on
thus for three months, but at last learnt caution, and ceased to do so.
The plate of glass was then removed, but the pike would not attack these
particular fishes, though he would devour others which were afterwards
introduced; so strongly was the idea of a violent shock associated in his
feeble mind with the attempt on his former neighbours.  If a savage, who
had never seen a large plate-glass window, were to dash himself even once
against it, he would for a long time afterwards associate a shock with a
window-frame; but very differently from the pike, he would probably reflect
on the nature of the impediment, and be cautious under analogous
circumstances.  Now with monkeys, as we shall presently see, a painful or
merely a disagreeable impression, from an action once performed, is
sometimes sufficient to prevent the animal from repeating it.  If we
attribute this difference between the monkey and the pike solely to the
association of ideas being so much stronger and more persistent in the one
than the other, though the pike often received much the more severe injury,
can we maintain in the case of man that a similar difference implies the
possession of a fundamentally different mind?

Houzeau relates (24.  'Etudes sur les Facultes Mentales des Animaux,' 1872,
tom. ii. p. 265.) that, whilst crossing a wide and arid plain in Texas, his
two dogs suffered greatly from thirst, and that between thirty and forty
times they rushed down the hollows to search for water.  These hollows were
not valleys, and there were no trees in them, or any other difference in
the vegetation, and as they were absolutely dry there could have been no
smell of damp earth.  The dogs behaved as if they knew that a dip in the
ground offered them the best chance of finding water, and Houzeau has often
witnessed the same behaviour in other animals.

I have seen, as I daresay have others, that when a small object is thrown
on the ground beyond the reach of one of the elephants in the Zoological
Gardens, he blows through his trunk on the ground beyond the object, so
that the current reflected on all sides may drive the object within his
reach.  Again a well-known ethnologist, Mr. Westropp, informs me that he
observed in Vienna a bear deliberately making with his paw a current in
some water, which was close to the bars of his cage, so as to draw a piece
of floating bread within his reach.  These actions of the elephant and bear
can hardly be attributed to instinct or inherited habit, as they would be
of little use to an animal in a state of nature.  Now, what is the
difference between such actions, when performed by an uncultivated man, and
by one of the higher animals?

The savage and the dog have often found water at a low level, and the
coincidence under such circumstances has become associated in their minds.
A cultivated man would perhaps make some general proposition on the
subject; but from all that we know of savages it is extremely doubtful
whether they would do so, and a dog certainly would not.  But a savage, as
well as a dog, would search in the same way, though frequently
disappointed; and in both it seems to be equally an act of reason, whether
or not any general proposition on the subject is consciously placed before
the mind.  (25.  Prof. Huxley has analysed with admirable clearness the
mental steps by which a man, as well as a dog, arrives at a conclusion in a
case analogous to that given in my text.  See his article, 'Mr. Darwin's
Critics,' in the 'Contemporary Review,' Nov. 1871, p. 462, and in his
'Critiques and Essays,' 1873, p. 279.)  The same would apply to the
elephant and the bear making currents in the air or water.  The savage
would certainly neither know nor care by what law the desired movements
were effected; yet his act would be guided by a rude process of reasoning,
as surely as would a philosopher in his longest chain of deductions.  There
would no doubt be this difference between him and one of the higher
animals, that he would take notice of much slighter circumstances and
conditions, and would observe any connection between them after much less
experience, and this would be of paramount importance.  I kept a daily
record of the actions of one of my infants, and when he was about eleven
months old, and before he could speak a single word, I was continually
struck with the greater quickness, with which all sorts of objects and
sounds were associated together in his mind, compared with that of the most
intelligent dogs I ever knew.  But the higher animals differ in exactly the
same way in this power of association from those low in the scale, such as
the pike, as well as in that of drawing inferences and of observation.

The promptings of reason, after very short experience, are well shewn by
the following actions of American monkeys, which stand low in their order.
Rengger, a most careful observer, states that when he first gave eggs to
his monkeys in Paraguay, they smashed them, and thus lost much of their
contents; afterwards they gently hit one end against some hard body, and
picked off the bits of shell with their fingers.  After cutting themselves
only ONCE with any sharp tool, they would not touch it again, or would
handle it with the greatest caution.  Lumps of sugar were often given them
wrapped up in paper; and Rengger sometimes put a live wasp in the paper, so
that in hastily unfolding it they got stung; after this had ONCE happened,
they always first held the packet to their ears to detect any movement
within.  (26.  Mr. Belt, in his most interesting work, 'The Naturalist in
Nicaragua,' 1874, (p. 119), likewise describes various actions of a tamed
Cebus, which, I think, clearly shew that this animal possessed some
reasoning power.)

The following cases relate to dogs.  Mr. Colquhoun (27.  'The Moor and the
Loch,' p. 45.  Col. Hutchinson on 'Dog Breaking,' 1850, p. 46.) winged two
wild-ducks, which fell on the further side of a stream; his retriever tried
to bring over both at once, but could not succeed; she then, though never
before known to ruffle a feather, deliberately killed one, brought over the
other, and returned for the dead bird.  Col. Hutchinson relates that two
partridges were shot at once, one being killed, the other wounded; the
latter ran away, and was caught by the retriever, who on her return came
across the dead bird; "she stopped, evidently greatly puzzled, and after
one or two trials, finding she could not take it up without permitting the
escape of the winged bird, she considered a moment, then deliberately
murdered it by giving it a severe crunch, and afterwards brought away both
together.  This was the only known instance of her ever having wilfully
injured any game."  Here we have reason though not quite perfect, for the
retriever might have brought the wounded bird first and then returned for
the dead one, as in the case of the two wild-ducks.  I give the above
cases, as resting on the evidence of two independent witnesses, and because
in both instances the retrievers, after deliberation, broke through a habit
which is inherited by them (that of not killing the game retrieved), and
because they shew how strong their reasoning faculty must have been to
overcome a fixed habit.

I will conclude by quoting a remark by the illustrious Humboldt.  (28.
'Personal Narrative,' Eng. translat., vol. iii. p. 106.)  "The muleteers in
S. America say, 'I will not give you the mule whose step is easiest, but la
mas racional,--the one that reasons best'"; and; as, he adds, "this popular
expression, dictated by long experience, combats the system of animated
machines, better perhaps than all the arguments of speculative philosophy."
Nevertheless some writers even yet deny that the higher animals possess a
trace of reason; and they endeavour to explain away, by what appears to be
mere verbiage, (29.  I am glad to find that so acute a reasoner as Mr.
Leslie Stephen ('Darwinism and Divinity, Essays on Free Thinking,' 1873, p.
80), in speaking of the supposed impassable barrier between the minds of
man and the lower animals, says, "The distinctions, indeed, which have been
drawn, seem to us to rest upon no better foundation than a great many other
metaphysical distinctions; that is, the assumption that because you can
give two things different names, they must therefore have different
natures.  It is difficult to understand how anybody who has ever kept a
dog, or seen an elephant, can have any doubt as to an animal's power of
performing the essential processes of reasoning.") all such facts as those
above given.

It has, I think, now been shewn that man and the higher animals, especially
the Primates, have some few instincts in common.  All have the same senses,
intuitions, and sensations,--similar passions, affections, and emotions,
even the more complex ones, such as jealousy, suspicion, emulation,
gratitude, and magnanimity; they practise deceit and are revengeful; they
are sometimes susceptible to ridicule, and even have a sense of humour;
they feel wonder and curiosity; they possess the same faculties of
imitation, attention, deliberation, choice, memory, imagination, the
association of ideas, and reason, though in very different degrees.  The
individuals of the same species graduate in intellect from absolute
imbecility to high excellence.  They are also liable to insanity, though
far less often than in the case of man.  (30.  See 'Madness in Animals,' by
Dr. W. Lauder Lindsay, in 'Journal of Mental Science,' July 1871.)
Nevertheless, many authors have insisted that man is divided by an
insuperable barrier from all the lower animals in his mental faculties.  I
formerly made a collection of above a score of such aphorisms, but they are
almost worthless, as their wide difference and number prove the difficulty,
if not the impossibility, of the attempt.  It has been asserted that man
alone is capable of progressive improvement; that he alone makes use of
tools or fire, domesticates other animals, or possesses property; that no
animal has the power of abstraction, or of forming general concepts, is
self-conscious and comprehends itself; that no animal employs language;
that man alone has a sense of beauty, is liable to caprice, has the feeling
of gratitude, mystery, etc.; believes in God, or is endowed with a
conscience.  I will hazard a few remarks on the more important and
interesting of these points.

Archbishop Sumner formerly maintained (31.  Quoted by Sir C. Lyell,
'Antiquity of Man,' p. 497.) that man alone is capable of progressive
improvement.  That he is capable of incomparably greater and more rapid
improvement than is any other animal, admits of no dispute; and this is
mainly due to his power of speaking and handing down his acquired
knowledge.  With animals, looking first to the individual, every one who
has had any experience in setting traps, knows that young animals can be
caught much more easily than old ones; and they can be much more easily
approached by an enemy.  Even with respect to old animals, it is impossible
to catch many in the same place and in the same kind of trap, or to destroy
them by the same kind of poison; yet it is improbable that all should have
partaken of the poison, and impossible that all should have been caught in
a trap.  They must learn caution by seeing their brethren caught or
poisoned.  In North America, where the fur-bearing animals have long been
pursued, they exhibit, according to the unanimous testimony of all
observers, an almost incredible amount of sagacity, caution and cunning;
but trapping has been there so long carried on, that inheritance may
possibly have come into play.  I have received several accounts that when
telegraphs are first set up in any district, many birds kill themselves by
flying against the wires, but that in the course of a very few years they
learn to avoid this danger, by seeing, as it would appear, their comrades
killed.  (32.  For additional evidence, with details, see M. Houzeau,
'Etudes sur les Facultes Mentales des Animaux,' tom. ii. 1872, p. 147.)

If we look to successive generations, or to the race, there is no doubt
that birds and other animals gradually both acquire and lose caution in
relation to man or other enemies (33.  See, with respect to birds on
oceanic islands, my 'Journal of Researches during the Voyage of the
"Beagle,"' 1845, p. 398.  'Origin of Species,' 5th ed. p. 260.); and this
caution is certainly in chief part an inherited habit or instinct, but in
part the result of individual experience.  A good observer, Leroy (34.
'Lettres Phil. sur l'Intelligence des Animaux,' nouvelle edit., 1802, p.
86.), states, that in districts where foxes are much hunted, the young, on
first leaving their burrows, are incontestably much more wary than the old
ones in districts where they are not much disturbed.

Our domestic dogs are descended from wolves and jackals (35.  See the
evidence on this head in chap. i. vol. i., 'On the Variation of Animals and
Plants under Domestication.'), and though they may not have gained in
cunning, and may have lost in wariness and suspicion, yet they have
progressed in certain moral qualities, such as in affection, trust-
worthiness, temper, and probably in general intelligence.  The common rat
has conquered and beaten several other species throughout Europe, in parts
of North America, New Zealand, and recently in Formosa, as well as on the
mainland of China.  Mr. Swinhoe (36.  'Proceedings Zoological Society,'
1864, p. 186.), who describes these two latter cases, attributes the
victory of the common rat over the large Mus coninga to its superior
cunning; and this latter quality may probably be attributed to the habitual
exercise of all its faculties in avoiding extirpation by man, as well as to
nearly all the less cunning or weak-minded rats having been continuously
destroyed by him.  It is, however, possible that the success of the common
rat may be due to its having possessed greater cunning than its fellow-
species, before it became associated with man.  To maintain, independently
of any direct evidence, that no animal during the course of ages has
progressed in intellect or other mental faculties, is to beg the question
of the evolution of species.  We have seen that, according to Lartet,
existing mammals belonging to several orders have larger brains than their
ancient tertiary prototypes.

It has often been said that no animal uses any tool; but the chimpanzee in
a state of nature cracks a native fruit, somewhat like a walnut, with a
stone.  (37.  Savage and Wyman in 'Boston Journal of Natural History,' vol.
iv. 1843-44, p. 383.)  Rengger (38.  'Saeugethiere von Paraguay,' 1830, s.
51-56.) easily taught an American monkey thus to break open hard palm-nuts;
and afterwards of its own accord, it used stones to open other kinds of
nuts, as well as boxes.  It thus also removed the soft rind of fruit that
had a disagreeable flavour.  Another monkey was taught to open the lid of a
large box with a stick, and afterwards it used the stick as a lever to move
heavy bodies; and I have myself seen a young orang put a stick into a
crevice, slip his hand to the other end, and use it in the proper manner as
a lever.  The tamed elephants in India are well known to break off branches
of trees and use them to drive away the flies; and this same act has been
observed in an elephant in a state of nature.  (39.  The Indian Field,
March 4, 1871.)  I have seen a young orang, when she thought she was going
to be whipped, cover and protect herself with a blanket or straw.  In these
several cases stones and sticks were employed as implements; but they are
likewise used as weapons.  Brehm (40.  'Thierleben,' B. i. s. 79, 82.)
states, on the authority of the well-known traveller Schimper, that in
Abyssinia when the baboons belonging to one species (C. gelada) descend in
troops from the mountains to plunder the fields, they sometimes encounter
troops of another species (C. hamadryas), and then a fight ensues.  The
Geladas roll down great stones, which the Hamadryas try to avoid, and then
both species, making a great uproar, rush furiously against each other.
Brehm, when accompanying the Duke of Coburg-Gotha, aided in an attack with
fire-arms on a troop of baboons in the pass of Mensa in Abyssinia.  The
baboons in return rolled so many stones down the mountain, some as large as
a man's head, that the attackers had to beat a hasty retreat; and the pass
was actually closed for a time against the caravan.  It deserves notice
that these baboons thus acted in concert.  Mr. Wallace (41.  'The Malay
Archipelago,' vol. i. 1869, p. 87.) on three occasions saw female orangs,
accompanied by their young, "breaking off branches and the great spiny
fruit of the Durian tree, with every appearance of rage; causing such a
shower of missiles as effectually kept us from approaching too near the
tree."  As I have repeatedly seen, a chimpanzee will throw any object at
hand at a person who offends him; and the before-mentioned baboon at the
Cape of Good Hope prepared mud for the purpose.

In the Zoological Gardens, a monkey, which had weak teeth, used to break
open nuts with a stone; and I was assured by the keepers that after using
the stone, he hid it in the straw, and would not let any other monkey touch
it.  Here, then, we have the idea of property; but this idea is common to
every dog with a bone, and to most or all birds with their nests.

The Duke of Argyll (42.  'Primeval Man,' 1869, pp. 145, 147.) remarks, that
the fashioning of an implement for a special purpose is absolutely peculiar
to man; and he considers that this forms an immeasurable gulf between him
and the brutes.  This is no doubt a very important distinction; but there
appears to me much truth in Sir J. Lubbock's suggestion (43.  'Prehistoric
Times,' 1865, p. 473, etc.), that when primeval man first used flint-stones
for any purpose, he would have accidentally splintered them, and would then
have used the sharp fragments.  From this step it would be a small one to
break the flints on purpose, and not a very wide step to fashion them
rudely.  This latter advance, however, may have taken long ages, if we may
judge by the immense interval of time which elapsed before the men of the
neolithic period took to grinding and polishing their stone tools.  In
breaking the flints, as Sir J. Lubbock likewise remarks, sparks would have
been emitted, and in grinding them heat would have been evolved:  thus the
two usual methods of "obtaining fire may have originated."  The nature of
fire would have been known in the many volcanic regions where lava
occasionally flows through forests.  The anthropomorphous apes, guided
probably by instinct, build for themselves temporary platforms; but as many
instincts are largely controlled by reason, the simpler ones, such as this
of building a platform, might readily pass into a voluntary and conscious
act.  The orang is known to cover itself at night with the leaves of the
Pandanus; and Brehm states that one of his baboons used to protect itself
from the heat of the sun by throwing a straw-mat over its head.  In these
several habits, we probably see the first steps towards some of the simpler
arts, such as rude architecture and dress, as they arose amongst the early
progenitors of man.

ABSTRACTION, GENERAL CONCEPTIONS, SELF-CONSCIOUSNESS, MENTAL INDIVIDUALITY.

It would be very difficult for any one with even much more knowledge than I
possess, to determine how far animals exhibit any traces of these high
mental powers.  This difficulty arises from the impossibility of judging
what passes through the mind of an animal; and again, the fact that writers
differ to a great extent in the meaning which they attribute to the above
terms, causes a further difficulty.  If one may judge from various articles
which have been published lately, the greatest stress seems to be laid on
the supposed entire absence in animals of the power of abstraction, or of
forming general concepts.  But when a dog sees another dog at a distance,
it is often clear that he perceives that it is a dog in the abstract; for
when he gets nearer his whole manner suddenly changes, if the other dog be
a friend.  A recent writer remarks, that in all such cases it is a pure
assumption to assert that the mental act is not essentially of the same
nature in the animal as in man.  If either refers what he perceives with
his senses to a mental concept, then so do both.  (44.  Mr. Hookham, in a
letter to Prof. Max Muller, in the 'Birmingham News,' May 1873.)  When I
say to my terrier, in an eager voice (and I have made the trial many
times), "Hi, hi, where is it?" she at once takes it as a sign that
something is to be hunted, and generally first looks quickly all around,
and then rushes into the nearest thicket, to scent for any game, but
finding nothing, she looks up into any neighbouring tree for a squirrel.
Now do not these actions clearly shew that she had in her mind a general
idea or concept that some animal is to be discovered and hunted?

It may be freely admitted that no animal is self-conscious, if by this term
it is implied, that he reflects on such points, as whence he comes or
whither he will go, or what is life and death, and so forth.  But how can
we feel sure that an old dog with an excellent memory and some power of
imagination, as shewn by his dreams, never reflects on his past pleasures
or pains in the chase?  And this would be a form of self-consciousness.  On
the other hand, as Buchner (45.  'Conferences sur la Theorie Darwinienne,'
French translat. 1869, p. 132.) has remarked, how little can the hard-
worked wife of a degraded Australian savage, who uses very few abstract
words, and cannot count above four, exert her self-consciousness, or
reflect on the nature of her own existence.  It is generally admitted, that
the higher animals possess memory, attention, association, and even some
imagination and reason.  If these powers, which differ much in different
animals, are capable of improvement, there seems no great improbability in
more complex faculties, such as the higher forms of abstraction, and self-
consciousness, etc., having been evolved through the development and
combination of the simpler ones.  It has been urged against the views here
maintained that it is impossible to say at what point in the ascending
scale animals become capable of abstraction, etc.; but who can say at what
age this occurs in our young children?  We see at least that such powers
are developed in children by imperceptible degrees.

That animals retain their mental individuality is unquestionable.  When my
voice awakened a train of old associations in the mind of the before-
mentioned dog, he must have retained his mental individuality, although
every atom of his brain had probably undergone change more than once during
the interval of five years.  This dog might have brought forward the
argument lately advanced to crush all evolutionists, and said, "I abide
amid all mental moods and all material changes...The teaching that atoms
leave their impressions as legacies to other atoms falling into the places
they have vacated is contradictory of the utterance of consciousness, and
is therefore false; but it is the teaching necessitated by evolutionism,
consequently the hypothesis is a false one."  (46.  The Rev. Dr. J. M'Cann,
'Anti-Darwinism,' 1869, p. 13.)

LANGUAGE.

This faculty has justly been considered as one of the chief distinctions
between man and the lower animals.  But man, as a highly competent judge,
Archbishop Whately remarks, "is not the only animal that can make use of
language to express what is passing in his mind, and can understand, more
or less, what is so expressed by another."  (47.  Quoted in
'Anthropological Review,' 1864, p. 158.)  In Paraguay the Cebus azarae when
excited utters at least six distinct sounds, which excite in other monkeys
similar emotions.  (48.  Rengger, ibid. s. 45.)  The movements of the
features and gestures of monkeys are understood by us, and they partly
understand ours, as Rengger and others declare.  It is a more remarkable
fact that the dog, since being domesticated, has learnt to bark (49.  See
my 'Variation of Animals and Plants under Domestication,' vol. i. p. 27.)
in at least four or five distinct tones.  Although barking is a new art, no
doubt the wild parent-species of the dog expressed their feelings by cries
of various kinds.  With the domesticated dog we have the bark of eagerness,
as in the chase; that of anger, as well as growling; the yelp or howl of
despair, as when shut up; the baying at night; the bark of joy, as when
starting on a walk with his master; and the very distinct one of demand or
supplication, as when wishing for a door or window to be opened.  According
to Houzeau, who paid particular attention to the subject, the domestic fowl
utters at least a dozen significant sounds.  (50.  'Facultes Mentales des
Animaux,' tom. ii. 1872, p. 346-349.)

The habitual use of articulate language is, however, peculiar to man; but
he uses, in common with the lower animals, inarticulate cries to express
his meaning, aided by gestures and the movements of the muscles of the
face.  (51.  See a discussion on this subject in Mr. E.B. Tylor's very
interesting work, 'Researches into the Early History of Mankind,' 1865,
chaps. ii. to iv.)  This especially holds good with the more simple and
vivid feelings, which are but little connected with our higher
intelligence.  Our cries of pain, fear, surprise, anger, together with
their appropriate actions, and the murmur of a mother to her beloved child
are more expressive than any words.  That which distinguishes man from the
lower animals is not the understanding of articulate sounds, for, as every
one knows, dogs understand many words and sentences.  In this respect they
are at the same stage of development as infants, between the ages of ten
and twelve months, who understand many words and short sentences, but
cannot yet utter a single word.  It is not the mere articulation which is
our distinguishing character, for parrots and other birds possess this
power.  Nor is it the mere capacity of connecting definite sounds with
definite ideas; for it is certain that some parrots, which have been taught
to speak, connect unerringly words with things, and persons with events.
(52.  I have received several detailed accounts to this effect.  Admiral
Sir B.J. Sulivan, whom I know to be a careful observer, assures me that an
African parrot, long kept in his father's house, invariably called certain
persons of the household, as well as visitors, by their names.  He said
"good morning" to every one at breakfast, and "good night" to each as they
left the room at night, and never reversed these salutations.  To Sir B.J.
Sulivan's father, he used to add to the " good morning" a short sentence,
which was never once repeated after his father's death.  He scolded
violently a strange dog which came into the room through the open window;
and he scolded another parrot (saying "you naughty polly") which had got
out of its cage, and was eating apples on the kitchen table.  See also, to
the same effect, Houzeau on parrots, 'Facultes Mentales,' tom. ii. p. 309.
Dr. A. Moschkau informs me that he knew a starling which never made a
mistake in saying in German "good morning" to persons arriving, and "good
bye, old fellow," to those departing.  I could add several other such
cases.)  The lower animals differ from man solely in his almost infinitely
larger power of associating together the most diversified sounds and ideas;
and this obviously depends on the high development of his mental powers.

As Horne Tooke, one of the founders of the noble science of philology,
observes, language is an art, like brewing or baking; but writing would
have been a better simile.  It certainly is not a true instinct, for every
language has to be learnt.  It differs, however, widely from all ordinary
arts, for man has an instinctive tendency to speak, as we see in the babble
of our young children; whilst no child has an instinctive tendency to brew,
bake, or write.  Moreover, no philologist now supposes that any language
has been deliberately invented; it has been slowly and unconsciously
developed by many steps.  (53.  See some good remarks on this head by Prof.
Whitney, in his 'Oriental and Linguistic Studies,' 1873, p. 354.  He
observes that the desire of communication between man is the living force,
which, in the development of language, "works both consciously and
unconsciously; consciously as regards the immediate end to be attained;
unconsciously as regards the further consequences of the act.")  The sounds
uttered by birds offer in several respects the nearest analogy to language,
for all the members of the same species utter the same instinctive cries
expressive of their emotions; and all the kinds which sing, exert their
power instinctively; but the actual song, and even the call-notes, are
learnt from their parents or foster-parents.  These sounds, as Daines
Barrington (54.  Hon. Daines Barrington in 'Philosoph. Transactions,' 1773,
p. 262.  See also Dureau de la Malle, in 'Ann. des. Sc. Nat.' 3rd series,
Zoolog., tom. x. p. 119.) has proved, "are no more innate than language is
in man."  The first attempts to sing "may be compared to the imperfect
endeavour in a child to babble."  The young males continue practising, or
as the bird-catchers say, "recording," for ten or eleven months.  Their
first essays shew hardly a rudiment of the future song; but as they grow
older we can perceive what they are aiming at; and at last they are said
"to sing their song round."  Nestlings which have learnt the song of a
distinct species, as with the canary-birds educated in the Tyrol, teach and
transmit their new song to their offspring.  The slight natural differences
of song in the same species inhabiting different districts may be
appositely compared, as Barrington remarks, "to provincial dialects"; and
the songs of allied, though distinct species may be compared with the
languages of distinct races of man.  I have given the foregoing details to
shew that an instinctive tendency to acquire an art is not peculiar to man.

With respect to the origin of articulate language, after having read on the
one side the highly interesting works of Mr. Hensleigh Wedgwood, the Rev.
F. Farrar, and Prof. Schleicher (55.  'On the Origin of Language,' by H.
Wedgwood, 1866.  'Chapters on Language,' by the Rev. F.W. Farrar, 1865.
These works are most interesting.  See also 'De la Phys. et de Parole,' par
Albert Lemoine, 1865, p. 190.  The work on this subject, by the late Prof.
Aug. Schleicher, has been translated by Dr. Bikkers into English, under the
title of 'Darwinism tested by the Science of Language,' 1869.), and the
celebrated lectures of Prof. Max Muller on the other side, I cannot doubt
that language owes its origin to the imitation and modification of various
natural sounds, the voices of other animals, and man's own instinctive
cries, aided by signs and gestures.  When we treat of sexual selection we
shall see that primeval man, or rather some early progenitor of man,
probably first used his voice in producing true musical cadences, that is
in singing, as do some of the gibbon-apes at the present day; and we may
conclude from a widely-spread analogy, that this power would have been
especially exerted during the courtship of the sexes,--would have expressed
various emotions, such as love, jealousy, triumph,--and would have served
as a challenge to rivals.  It is, therefore, probable that the imitation of
musical cries by articulate sounds may have given rise to words expressive
of various complex emotions.  The strong tendency in our nearest allies,
the monkeys, in microcephalous idiots (56.  Vogt, 'Memoire sur les
Microcephales,' 1867, p. 169.  With respect to savages, I have given some
facts in my 'Journal of Researches,' etc., 1845, p. 206.), and in the
barbarous races of mankind, to imitate whatever they hear deserves notice,
as bearing on the subject of imitation.  Since monkeys certainly understand
much that is said to them by man, and when wild, utter signal-cries of
danger to their fellows (57.  See clear evidence on this head in the two
works so often quoted, by Brehm and Rengger.); and since fowls give
distinct warnings for danger on the ground, or in the sky from hawks (both,
as well as a third cry, intelligible to dogs) (58.  Houzeau gives a very
curious account of his observations on this subject in his 'Facultes
Mentales des Animaux,' tom. ii. p. 348.), may not some unusually wise ape-
like animal have imitated the growl of a beast of prey, and thus told his
fellow-monkeys the nature of the expected danger?  This would have been a
first step in the formation of a language.

As the voice was used more and more, the vocal organs would have been
strengthened and perfected through the principle of the inherited effects
of use; and this would have reacted on the power of speech.  But the
relation between the continued use of language and the development of the
brain, has no doubt been far more important.  The mental powers in some
early progenitor of man must have been more highly developed than in any
existing ape, before even the most imperfect form of speech could have come
into use; but we may confidently believe that the continued use and
advancement of this power would have reacted on the mind itself, by
enabling and encouraging it to carry on long trains of thought.  A complex
train of thought can no more be carried on without the aid of words,
whether spoken or silent, than a long calculation without the use of
figures or algebra.  It appears, also, that even an ordinary train of
thought almost requires, or is greatly facilitated by some form of
language, for the dumb, deaf, and blind girl, Laura Bridgman, was observed
to use her fingers whilst dreaming.  (59.  See remarks on this head by Dr.
Maudsley, 'The Physiology and Pathology of Mind,' 2nd ed., 1868, p. 199.)
Nevertheless, a long succession of vivid and connected ideas may pass
through the mind without the aid of any form of language, as we may infer
from the movements of dogs during their dreams.  We have, also, seen that
animals are able to reason to a certain extent, manifestly without the aid
of language.  The intimate connection between the brain, as it is now
developed in us, and the faculty of speech, is well shewn by those curious
cases of brain-disease in which speech is specially affected, as when the
power to remember substantives is lost, whilst other words can be correctly
used, or where substantives of a certain class, or all except the initial
letters of substantives and proper names are forgotten.  (60.  Many curious
cases have been recorded.  See, for instance, Dr. Bateman 'On Aphasia,'
1870, pp. 27, 31, 53, 100, etc.  Also, 'Inquiries Concerning the
Intellectual Powers,' by Dr. Abercrombie, 1838, p. 150.)  There is no more
improbability in the continued use of the mental and vocal organs leading
to inherited changes in their structure and functions, than in the case of
hand-writing, which depends partly on the form of the hand and partly on
the disposition of the mind; and handwriting is certainly inherited.  (61.
'The Variation of Animals and Plants under Domestication,' vol. ii. p. 6.')

Several writers, more especially Prof. Max Muller (62.  Lectures on 'Mr.
Darwin's Philosophy of Language,' 1873.), have lately insisted that the use
of language implies the power of forming general concepts; and that as no
animals are supposed to possess this power, an impassable barrier is formed
between them and man.  (63.  The judgment of a distinguished philologist,
such as Prof. Whitney, will have far more weight on this point than
anything that I can say.  He remarks ('Oriental and Linguistic Studies,'
1873, p. 297), in speaking of Bleek's views:  "Because on the grand scale
language is the necessary auxiliary of thought, indispensable to the
development of the power of thinking, to the distinctness and variety and
complexity of cognitions to the full mastery of consciousness; therefore he
would fain make thought absolutely impossible without speech, identifying
the faculty with its instrument.  He might just as reasonably assert that
the human hand cannot act without a tool.  With such a doctrine to start
from, he cannot stop short of Max Muller's worst paradoxes, that an infant
(in fans, not speaking) is not a human being, and that deaf-mutes do not
become possessed of reason until they learn to twist their fingers into
imitation of spoken words."  Max Muller gives in italics ('Lectures on Mr.
Darwin's Philosophy of Language,' 1873, third lecture) this aphorism:
"There is no thought without words, as little as there are words without
thought."  What a strange definition must here be given to the word
thought!)  With respect to animals, I have already endeavoured to shew that
they have this power, at least in a rude and incipient degree.  As far as
concerns infants of from ten to eleven months old, and deaf-mutes, it seems
to me incredible, that they should be able to connect certain sounds with
certain general ideas as quickly as they do, unless such ideas were already
formed in their minds.  The same remark may be extended to the more
intelligent animals; as Mr. Leslie Stephen observes (64.  'Essays on Free
Thinking,' etc., 1873, p. 82.), "A dog frames a general concept of cats or
sheep, and knows the corresponding words as well as a philosopher.  And the
capacity to understand is as good a proof of vocal intelligence, though in
an inferior degree, as the capacity to speak."

Why the organs now used for speech should have been originally perfected
for this purpose, rather than any other organs, it is not difficult to see.
Ants have considerable powers of intercommunication by means of their
antennae, as shewn by Huber, who devotes a whole chapter to their language.
We might have used our fingers as efficient instruments, for a person with
practice can report to a deaf man every word of a speech rapidly delivered
at a public meeting; but the loss of our hands, whilst thus employed, would
have been a serious inconvenience.  As all the higher mammals possess vocal
organs, constructed on the same general plan as ours, and used as a means
of communication, it was obviously probable that these same organs would be
still further developed if the power of communication had to be improved;
and this has been effected by the aid of adjoining and well adapted parts,
namely the tongue and lips.  (65.  See some good remarks to this effect by
Dr. Maudsley, 'The Physiology and Pathology of Mind,' 1868, p. 199.)  The
fact of the higher apes not using their vocal organs for speech, no doubt
depends on their intelligence not having been sufficiently advanced.  The
possession by them of organs, which with long-continued practice might have
been used for speech, although not thus used, is paralleled by the case of
many birds which possess organs fitted for singing, though they never sing.
Thus, the nightingale and crow have vocal organs similarly constructed,
these being used by the former for diversified song, and by the latter only
for croaking.  (66.  Macgillivray, 'Hist. of British Birds,' vol. ii. 1839,
p. 29.  An excellent observer, Mr. Blackwall, remarks that the magpie
learns to pronounce single words, and even short sentences, more readily
than almost any other British bird; yet, as he adds, after long and closely
investigating its habits, he has never known it, in a state of nature,
display any unusual capacity for imitation.  'Researches in Zoology,' 1834,
p. 158.)  If it be asked why apes have not had their intellects developed
to the same degree as that of man, general causes only can be assigned in
answer, and it is unreasonable to expect any thing more definite,
considering our ignorance with respect to the successive stages of
development through which each creature has passed.

The formation of different languages and of distinct species, and the
proofs that both have been developed through a gradual process, are
curiously parallel.  (67.  See the very interesting parallelism between the
development of species and languages, given by Sir C. Lyell in 'The
Geological Evidences of the Antiquity of Man,' 1863, chap. xxiii.)  But we
can trace the formation of many words further back than that of species,
for we can perceive how they actually arose from the imitation of various
sounds.  We find in distinct languages striking homologies due to community
of descent, and analogies due to a similar process of formation.  The
manner in which certain letters or sounds change when others change is very
like correlated growth.  We have in both cases the reduplication of parts,
the effects of long-continued use, and so forth.  The frequent presence of
rudiments, both in languages and in species, is still more remarkable.  The
letter m in the word am, means I; so that in the expression I am, a
superfluous and useless rudiment has been retained.  In the spelling also
of words, letters often remain as the rudiments of ancient forms of
pronunciation.  Languages, like organic beings, can be classed in groups
under groups; and they can be classed either naturally according to
descent, or artificially by other characters.  Dominant languages and
dialects spread widely, and lead to the gradual extinction of other
tongues.  A language, like a species, when once extinct, never, as Sir C.
Lyell remarks, reappears.  The same language never has two birth-places.
Distinct languages may be crossed or blended together.  (68.  See remarks
to this effect by the Rev. F.W. Farrar, in an interesting article, entitled
'Philology and Darwinism,' in 'Nature,' March 24th, 1870, p. 528.)  We see
variability in every tongue, and new words are continually cropping up; but
as there is a limit to the powers of the memory, single words, like whole
languages, gradually become extinct.  As Max Muller (69.  'Nature,' January
6th, 1870, p. 257.) has well remarked:--"A struggle for life is constantly
going on amongst the words and grammatical forms in each language.  The
better, the shorter, the easier forms are constantly gaining the upper
hand, and they owe their success to their own inherent virtue."  To these
more important causes of the survival of certain words, mere novelty and
fashion may be added; for there is in the mind of man a strong love for
slight changes in all things.  The survival or preservation of certain
favoured words in the struggle for existence is natural selection.

The perfectly regular and wonderfully complex construction of the languages
of many barbarous nations has often been advanced as a proof, either of the
divine origin of these languages, or of the high art and former
civilisation of their founders.  Thus F. von Schlegel writes:  "In those
languages which appear to be at the lowest grade of intellectual culture,
we frequently observe a very high and elaborate degree of art in their
grammatical structure.  This is especially the case with the Basque and the
Lapponian, and many of the American languages."  (70.  Quoted by C.S. Wake,
'Chapters on Man,' 1868, p. 101.)  But it is assuredly an error to speak of
any language as an art, in the sense of its having been elaborately and
methodically formed.  Philologists now admit that conjugations,
declensions, etc., originally existed as distinct words, since joined
together; and as such words express the most obvious relations between
objects and persons, it is not surprising that they should have been used
by the men of most races during the earliest ages.  With respect to
perfection, the following illustration will best shew how easily we may
err:  a Crinoid sometimes consists of no less than 150,000 pieces of shell
(71.  Buckland, 'Bridgewater Treatise,' p. 411.), all arranged with perfect
symmetry in radiating lines; but a naturalist does not consider an animal
of this kind as more perfect than a bilateral one with comparatively few
parts, and with none of these parts alike, excepting on the opposite sides
of the body.  He justly considers the differentiation and specialisation of
organs as the test of perfection.  So with languages:  the most symmetrical
and complex ought not to be ranked above irregular, abbreviated, and
bastardised languages, which have borrowed expressive words and useful
forms of construction from various conquering, conquered, or immigrant
races.

From these few and imperfect remarks I conclude that the extremely complex
and regular construction of many barbarous languages, is no proof that they
owe their origin to a special act of creation.  (72.  See some good remarks
on the simplification of languages, by Sir J. Lubbock, 'Origin of
Civilisation,' 1870, p. 278.)  Nor, as we have seen, does the faculty of
articulate speech in itself offer any insuperable objection to the belief
that man has been developed from some lower form.

SENSE OF BEAUTY.

This sense has been declared to be peculiar to man.  I refer here only to
the pleasure given by certain colours, forms, and sounds, and which may
fairly be called a sense of the beautiful; with cultivated men such
sensations are, however, intimately associated with complex ideas and
trains of thought.  When we behold a male bird elaborately displaying his
graceful plumes or splendid colours before the female, whilst other birds,
not thus decorated, make no such display, it is impossible to doubt that
she admires the beauty of her male partner.  As women everywhere deck
themselves with these plumes, the beauty of such ornaments cannot be
disputed.  As we shall see later, the nests of humming-birds, and the
playing passages of bower-birds are tastefully ornamented with gaily-
coloured objects; and this shews that they must receive some kind of
pleasure from the sight of such things.  With the great majority of
animals, however, the taste for the beautiful is confined, as far as we can
judge, to the attractions of the opposite sex.  The sweet strains poured
forth by many male birds during the season of love, are certainly admired
by the females, of which fact evidence will hereafter be given.  If female
birds had been incapable of appreciating the beautiful colours, the
ornaments, and voices of their male partners, all the labour and anxiety
exhibited by the latter in displaying their charms before the females would
have been thrown away; and this it is impossible to admit.  Why certain
bright colours should excite pleasure cannot, I presume, be explained, any
more than why certain flavours and scents are agreeable; but habit has
something to do with the result, for that which is at first unpleasant to
our senses, ultimately becomes pleasant, and habits are inherited.  With
respect to sounds, Helmholtz has explained to a certain extent on
physiological principles, why harmonies and certain cadences are agreeable.
But besides this, sounds frequently recurring at irregular intervals are
highly disagreeable, as every one will admit who has listened at night to
the irregular flapping of a rope on board ship.  The same principle seems
to come into play with vision, as the eye prefers symmetry or figures with
some regular recurrence.  Patterns of this kind are employed by even the
lowest savages as ornaments; and they have been developed through sexual
selection for the adornment of some male animals.  Whether we can or not
give any reason for the pleasure thus derived from vision and hearing, yet
man and many of the lower animals are alike pleased by the same colours,
graceful shading and forms, and the same sounds.

The taste for the beautiful, at least as far as female beauty is concerned,
is not of a special nature in the human mind; for it differs widely in the
different races of man, and is not quite the same even in the different
nations of the same race.  Judging from the hideous ornaments, and the
equally hideous music admired by most savages, it might be urged that their
aesthetic faculty was not so highly developed as in certain animals, for
instance, as in birds.  Obviously no animal would be capable of admiring
such scenes as the heavens at night, a beautiful landscape, or refined
music; but such high tastes are acquired through culture, and depend on
complex associations; they are not enjoyed by barbarians or by uneducated
persons.

Many of the faculties, which have been of inestimable service to man for
his progressive advancement, such as the powers of the imagination, wonder,
curiosity, an undefined sense of beauty, a tendency to imitation, and the
love of excitement or novelty, could hardly fail to lead to capricious
changes of customs and fashions.  I have alluded to this point, because a
recent writer (73.  'The Spectator,' Dec. 4th, 1869, p. 1430.) has oddly
fixed on Caprice "as one of the most remarkable and typical differences
between savages and brutes."  But not only can we partially understand how
it is that man is from various conflicting influences rendered capricious,
but that the lower animals are, as we shall hereafter see, likewise
capricious in their affections, aversions, and sense of beauty.  There is
also reason to suspect that they love novelty, for its own sake.

BELIEF IN GOD--RELIGION.

There is no evidence that man was aboriginally endowed with the ennobling
belief in the existence of an Omnipotent God.  On the contrary there is
ample evidence, derived not from hasty travellers, but from men who have
long resided with savages, that numerous races have existed, and still
exist, who have no idea of one or more gods, and who have no words in their
languages to express such an idea.  (74.  See an excellent article on this
subject by the Rev. F.W. Farrar, in the 'Anthropological Review,' Aug.
1864, p. ccxvii.  For further facts see Sir J. Lubbock, 'Prehistoric
Times,' 2nd edit., 1869, p. 564; and especially the chapters on Religion in
his 'Origin of Civilisation,' 1870.)  The question is of course wholly
distinct from that higher one, whether there exists a Creator and Ruler of
the universe; and this has been answered in the affirmative by some of the
highest intellects that have ever existed.

If, however, we include under the term "religion" the belief in unseen or
spiritual agencies, the case is wholly different; for this belief seems to
be universal with the less civilised races.  Nor is it difficult to
comprehend how it arose.  As soon as the important faculties of the
imagination, wonder, and curiosity, together with some power of reasoning,
had become partially developed, man would naturally crave to understand
what was passing around him, and would have vaguely speculated on his own
existence.  As Mr. M'Lennan (75.  'The Worship of Animals and Plants,' in
the 'Fortnightly Review,' Oct. 1, 1869, p. 422.) has remarked, "Some
explanation of the phenomena of life, a man must feign for himself, and to
judge from the universality of it, the simplest hypothesis, and the first
to occur to men, seems to have been that natural phenomena are ascribable
to the presence in animals, plants, and things, and in the forces of
nature, of such spirits prompting to action as men are conscious they
themselves possess."  It is also probable, as Mr. Tylor has shewn, that
dreams may have first given rise to the notion of spirits; for savages do
not readily distinguish between subjective and objective impressions.  When
a savage dreams, the figures which appear before him are believed to have
come from a distance, and to stand over him; or "the soul of the dreamer
goes out on its travels, and comes home with a remembrance of what it has
seen."  (76.  Tylor, 'Early History of Mankind,' 1865, p. 6.  See also the
three striking chapters on the 'Development of Religion,' in Lubbock's
'Origin of Civilisation,' 1870.  In a like manner Mr. Herbert Spencer, in
his ingenious essay in the 'Fortnightly Review' (May 1st, 1870, p. 535),
accounts for the earliest forms of religious belief throughout the world,
by man being led through dreams, shadows, and other causes, to look at
himself as a double essence, corporeal and spiritual.  As the spiritual
being is supposed to exist after death and to be powerful, it is
propitiated by various gifts and ceremonies, and its aid invoked.  He then
further shews that names or nicknames given from some animal or other
object, to the early progenitors or founders of a tribe, are supposed after
a long interval to represent the real progenitor of the tribe; and such
animal or object is then naturally believed still to exist as a spirit, is
held sacred, and worshipped as a god.  Nevertheless I cannot but suspect
that there is a still earlier and ruder stage, when anything which
manifests power or movement is thought to be endowed with some form of
life, and with mental faculties analogous to our own.)  But until the
faculties of imagination, curiosity, reason, etc., had been fairly well
developed in the mind of man, his dreams would not have led him to believe
in spirits, any more than in the case of a dog.

The tendency in savages to imagine that natural objects and agencies are
animated by spiritual or living essences, is perhaps illustrated by a
little fact which I once noticed:  my dog, a full-grown and very sensible
animal, was lying on the lawn during a hot and still day; but at a little
distance a slight breeze occasionally moved an open parasol, which would
have been wholly disregarded by the dog, had any one stood near it.  As it
was, every time that the parasol slightly moved, the dog growled fiercely
and barked.  He must, I think, have reasoned to himself in a rapid and
unconscious manner, that movement without any apparent cause indicated the
presence of some strange living agent, and that no stranger had a right to
be on his territory.

The belief in spiritual agencies would easily pass into the belief in the
existence of one or more gods.  For savages would naturally attribute to
spirits the same passions, the same love of vengeance or simplest form of
justice, and the same affections which they themselves feel.  The Fuegians
appear to be in this respect in an intermediate condition, for when the
surgeon on board the "Beagle" shot some young ducklings as specimens, York
Minster declared in the most solemn manner, "Oh, Mr. Bynoe, much rain, much
snow, blow much"; and this was evidently a retributive punishment for
wasting human food.  So again he related how, when his brother killed a
"wild man," storms long raged, much rain and snow fell.  Yet we could never
discover that the Fuegians believed in what we should call a God, or
practised any religious rites; and Jemmy Button, with justifiable pride,
stoutly maintained that there was no devil in his land.  This latter
assertion is the more remarkable, as with savages the belief in bad spirits
is far more common than that in good ones.

The feeling of religious devotion is a highly complex one, consisting of
love, complete submission to an exalted and mysterious superior, a strong
sense of dependence (77.  See an able article on the 'Physical Elements of
Religion,' by Mr. L. Owen Pike, in 'Anthropological Review,' April 1870, p.
lxiii.), fear, reverence, gratitude, hope for the future, and perhaps other
elements.  No being could experience so complex an emotion until advanced
in his intellectual and moral faculties to at least a moderately high
level.  Nevertheless, we see some distant approach to this state of mind in
the deep love of a dog for his master, associated with complete submission,
some fear, and perhaps other feelings.  The behaviour of a dog when
returning to his master after an absence, and, as I may add, of a monkey to
his beloved keeper, is widely different from that towards their fellows.
In the latter case the transports of joy appear to be somewhat less, and
the sense of equality is shewn in every action.  Professor Braubach goes so
far as to maintain that a dog looks on his master as on a god.  (78.
'Religion, Moral, etc., der Darwin'schen Art-Lehre,' 1869, s. 53.  It is
said (Dr. W. Lauder Lindsay, 'Journal of Mental Science,' 1871, p. 43),
that Bacon long ago, and the poet Burns, held the same notion.)

The same high mental faculties which first led man to believe in unseen
spiritual agencies, then in fetishism, polytheism, and ultimately in
monotheism, would infallibly lead him, as long as his reasoning powers
remained poorly developed, to various strange superstitions and customs.
Many of these are terrible to think of--such as the sacrifice of human
beings to a blood-loving god; the trial of innocent persons by the ordeal
of poison or fire; witchcraft, etc.--yet it is well occasionally to reflect
on these superstitions, for they shew us what an infinite debt of gratitude
we owe to the improvement of our reason, to science, and to our accumulated
knowledge.  As Sir J. Lubbock (79.  'Prehistoric Times,' 2nd edit., p. 571.
In this work (p. 571) there will be found an excellent account of the many
strange and capricious customs of savages.) has well observed, "it is not
too much to say that the horrible dread of unknown evil hangs like a thick
cloud over savage life, and embitters every pleasure."  These miserable and
indirect consequences of our highest faculties may be compared with the
incidental and occasional mistakes of the instincts of the lower animals.


CHAPTER IV.

COMPARISON OF THE MENTAL POWERS OF MAN AND THE LOWER ANIMALS--continued.

The moral sense--Fundamental proposition--The qualities of social animals--
Origin of sociability--Struggle between opposed instincts--Man a social
animal--The more enduring social instincts conquer other less persistent
instincts--The social virtues alone regarded by savages--The self-regarding
virtues acquired at a later stage of development--The importance of the
judgment of the members of the same community on conduct--Transmission of
moral tendencies--Summary.

I fully subscribe to the judgment of those writers (1.  See, for instance,
on this subject, Quatrefages, 'Unite de l'Espece Humaine,' 1861, p. 21,
etc.) who maintain that of all the differences between man and the lower
animals, the moral sense or conscience is by far the most important.  This
sense, as Mackintosh (2.  'Dissertation on Ethical Philosophy,' 1837, p.
231, etc.) remarks, "has a rightful supremacy over every other principle of
human action"; it is summed up in that short but imperious word "ought," so
full of high significance.  It is the most noble of all the attributes of
man, leading him without a moment's hesitation to risk his life for that of
a fellow-creature; or after due deliberation, impelled simply by the deep
feeling of right or duty, to sacrifice it in some great cause.  Immanuel
Kant exclaims, "Duty!  Wondrous thought, that workest neither by fond
insinuation, flattery, nor by any threat, but merely by holding up thy
naked law in the soul, and so extorting for thyself always reverence, if
not always obedience; before whom all appetites are dumb, however secretly
they rebel; whence thy original?"  (3.  'Metaphysics of Ethics,' translated
by J.W. Semple, Edinburgh, 1836, p. 136.)

This great question has been discussed by many writers (4.  Mr. Bain gives
a list ('Mental and Moral Science,' 1868, pp. 543-725) of twenty-six
British authors who have written on this subject, and whose names are
familiar to every reader; to these, Mr. Bain's own name, and those of Mr.
Lecky, Mr. Shadworth Hodgson, Sir J. Lubbock, and others, might be added.)
of consummate ability; and my sole excuse for touching on it, is the
impossibility of here passing it over; and because, as far as I know, no
one has approached it exclusively from the side of natural history.  The
investigation possesses, also, some independent interest, as an attempt to
see how far the study of the lower animals throws light on one of the
highest psychical faculties of man.

The following proposition seems to me in a high degree probable--namely,
that any animal whatever, endowed with well-marked social instincts (5.
Sir B. Brodie, after observing that man is a social animal ('Psychological
Enquiries,' 1854, p. 192), asks the pregnant question, "ought not this to
settle the disputed question as to the existence of a moral sense?"
Similar ideas have probably occurred to many persons, as they did long ago
to Marcus Aurelius.  Mr. J.S. Mill speaks, in his celebrated work,
'Utilitarianism,' (1864, pp. 45, 46), of the social feelings as a "powerful
natural sentiment," and as "the natural basis of sentiment for utilitarian
morality."  Again he says, "Like the other acquired capacities above
referred to, the moral faculty, if not a part of our nature, is a natural
out-growth from it; capable, like them, in a certain small degree of
springing up spontaneously."  But in opposition to all this, he also
remarks, "if, as in my own belief, the moral feelings are not innate, but
acquired, they are not for that reason less natural."  It is with
hesitation that I venture to differ at all from so profound a thinker, but
it can hardly be disputed that the social feelings are instinctive or
innate in the lower animals; and why should they not be so in man?  Mr.
Bain (see, for instance, 'The Emotions and the Will,' 1865, p. 481) and
others believe that the moral sense is acquired by each individual during
his lifetime.  On the general theory of evolution this is at least
extremely improbable.  The ignoring of all transmitted mental qualities
will, as it seems to me, be hereafter judged as a most serious blemish in
the works of Mr. Mill.), the parental and filial affections being here
included, would inevitably acquire a moral sense or conscience, as soon as
its intellectual powers had become as well, or nearly as well developed, as
in man.  For, FIRSTLY, the social instincts lead an animal to take pleasure
in the society of its fellows, to feel a certain amount of sympathy with
them, and to perform various services for them.  The services may be of a
definite and evidently instinctive nature; or there may be only a wish and
readiness, as with most of the higher social animals, to aid their fellows
in certain general ways.  But these feelings and services are by no means
extended to all the individuals of the same species, only to those of the
same association.  SECONDLY, as soon as the mental faculties had become
highly developed, images of all past actions and motives would be
incessantly passing through the brain of each individual:  and that feeling
of dissatisfaction, or even misery, which invariably results, as we shall
hereafter see, from any unsatisfied instinct, would arise, as often as it
was perceived that the enduring and always present social instinct had
yielded to some other instinct, at the time stronger, but neither enduring
in its nature, nor leaving behind it a very vivid impression.  It is clear
that many instinctive desires, such as that of hunger, are in their nature
of short duration; and after being satisfied, are not readily or vividly
recalled.  THIRDLY, after the power of language had been acquired, and the
wishes of the community could be expressed, the common opinion how each
member ought to act for the public good, would naturally become in a
paramount degree the guide to action.  But it should be borne in mind that
however great weight we may attribute to public opinion, our regard for the
approbation and disapprobation of our fellows depends on sympathy, which,
as we shall see, forms an essential part of the social instinct, and is
indeed its foundation-stone.  LASTLY, habit in the individual would
ultimately play a very important part in guiding the conduct of each
member; for the social instinct, together with sympathy, is, like any other
instinct, greatly strengthened by habit, and so consequently would be
obedience to the wishes and judgment of the community.  These several
subordinate propositions must now be discussed, and some of them at
considerable length.

It may be well first to premise that I do not wish to maintain that any
strictly social animal, if its intellectual faculties were to become as
active and as highly developed as in man, would acquire exactly the same
moral sense as ours.  In the same manner as various animals have some sense
of beauty, though they admire widely-different objects, so they might have
a sense of right and wrong, though led by it to follow widely different
lines of conduct.  If, for instance, to take an extreme case, men were
reared under precisely the same conditions as hive-bees, there can hardly
be a doubt that our unmarried females would, like the worker-bees, think it
a sacred duty to kill their brothers, and mothers would strive to kill
their fertile daughters; and no one would think of interfering.  (6.  Mr.
H. Sidgwick remarks, in an able discussion on this subject (the 'Academy,'
June 15, 1872, p. 231), "a superior bee, we may feel sure, would aspire to
a milder solution of the population question."  Judging, however, from the
habits of many or most savages, man solves the problem by female
infanticide, polyandry and promiscuous intercourse; therefore it may well
be doubted whether it would be by a milder method.  Miss Cobbe, in
commenting ('Darwinism in Morals,' 'Theological Review,' April 1872, pp.
188-191) on the same illustration, says, the PRINCIPLES of social duty
would be thus reversed; and by this, I presume, she means that the
fulfilment of a social duty would tend to the injury of individuals; but
she overlooks the fact, which she would doubtless admit, that the instincts
of the bee have been acquired for the good of the community.  She goes so
far as to say that if the theory of ethics advocated in this chapter were
ever generally accepted, "I cannot but believe that in the hour of their
triumph would be sounded the knell of the virtue of mankind!"  It is to be
hoped that the belief in the permanence of virtue on this earth is not held
by many persons on so weak a tenure.)  Nevertheless, the bee, or any other
social animal, would gain in our supposed case, as it appears to me, some
feeling of right or wrong, or a conscience.  For each individual would have
an inward sense of possessing certain stronger or more enduring instincts,
and others less strong or enduring; so that there would often be a struggle
as to which impulse should be followed; and satisfaction, dissatisfaction,
or even misery would be felt, as past impressions were compared during
their incessant passage through the mind.  In this case an inward monitor
would tell the animal that it would have been better to have followed the
one impulse rather than the other.  The one course ought to have been
followed, and the other ought not; the one would have been right and the
other wrong; but to these terms I shall recur.


SOCIABILITY.

Animals of many kinds are social; we find even distinct species living
together; for example, some American monkeys; and united flocks of rooks,
jackdaws, and starlings.  Man shews the same feeling in his strong love for
the dog, which the dog returns with interest.  Every one must have noticed
how miserable horses, dogs, sheep, etc., are when separated from their
companions, and what strong mutual affection the two former kinds, at
least, shew on their reunion.  It is curious to speculate on the feelings
of a dog, who will rest peacefully for hours in a room with his master or
any of the family, without the least notice being taken of him; but if left
for a short time by himself, barks or howls dismally.  We will confine our
attention to the higher social animals; and pass over insects, although
some of these are social, and aid one another in many important ways.  The
most common mutual service in the higher animals is to warn one another of
danger by means of the united senses of all.  Every sportsman knows, as Dr.
Jaeger remarks (7.  'Die Darwin'sche Theorie,' s. 101.), how difficult it
is to approach animals in a herd or troop.  Wild horses and cattle do not,
I believe, make any danger-signal; but the attitude of any one of them who
first discovers an enemy, warns the others.  Rabbits stamp loudly on the
ground with their hind-feet as a signal:  sheep and chamois do the same
with their forefeet, uttering likewise a whistle.  Many birds, and some
mammals, post sentinels, which in the case of seals are said (8.  Mr. R.
Brown in 'Proc. Zoolog. Soc.' 1868, p. 409.) generally to be the females.
The leader of a troop of monkeys acts as the sentinel, and utters cries
expressive both of danger and of safety.  (9.  Brehm, 'Thierleben,' B. i.
1864, s. 52, 79.  For the case of the monkeys extracting thorns from each
other, see s. 54.  With respect to the Hamadryas turning over stones, the
fact is given (s. 76), on the evidence of Alvarez, whose observations Brehm
thinks quite trustworthy.  For the cases of the old male baboons attacking
the dogs, see s. 79; and with respect to the eagle, s. 56.)  Social animals
perform many little services for each other:  horses nibble, and cows lick
each other, on any spot which itches:  monkeys search each other for
external parasites; and Brehm states that after a troop of the
Cercopithecus griseo-viridis has rushed through a thorny brake, each monkey
stretches itself on a branch, and another monkey sitting by,
"conscientiously" examines its fur, and extracts every thorn or burr.

Animals also render more important services to one another:  thus wolves
and some other beasts of prey hunt in packs, and aid one another in
attacking their victims.  Pelicans fish in concert.  The Hamadryas baboons
turn over stones to find insects, etc.; and when they come to a large one,
as many as can stand round, turn it over together and share the booty.
Social animals mutually defend each other.  Bull bisons in N. America, when
there is danger, drive the cows and calves into the middle of the herd,
whilst they defend the outside.  I shall also in a future chapter give an
account of two young wild bulls at Chillingham attacking an old one in
concert, and of two stallions together trying to drive away a third
stallion from a troop of mares.  In Abyssinia, Brehm encountered a great
troop of baboons who were crossing a valley:  some had already ascended the
opposite mountain, and some were still in the valley; the latter were
attacked by the dogs, but the old males immediately hurried down from the
rocks, and with mouths widely opened, roared so fearfully, that the dogs
quickly drew back.  They were again encouraged to the attack; but by this
time all the baboons had reascended the heights, excepting a young one,
about six months old, who, loudly calling for aid, climbed on a block of
rock, and was surrounded.  Now one of the largest males, a true hero, came
down again from the mountain, slowly went to the young one, coaxed him, and
triumphantly led him away--the dogs being too much astonished to make an
attack.  I cannot resist giving another scene which was witnessed by this
same naturalist; an eagle seized a young Cercopithecus, which, by clinging
to a branch, was not at once carried off; it cried loudly for assistance,
upon which the other members of the troop, with much uproar, rushed to the
rescue, surrounded the eagle, and pulled out so many feathers, that he no
longer thought of his prey, but only how to escape.  This eagle, as Brehm
remarks, assuredly would never again attack a single monkey of a troop.
(10.  Mr. Belt gives the case of a spider-monkey (Ateles) in Nicaragua,
which was heard screaming for nearly two hours in the forest, and was found
with an eagle perched close by it.  The bird apparently feared to attack as
long as it remained face to face; and Mr. Belt believes, from what he has
seen of the habits of these monkeys, that they protect themselves from
eagles by keeping two or three together.  'The Naturalist in Nicaragua,'
1874, p. 118.)

It is certain that associated animals have a feeling of love for each
other, which is not felt by non-social adult animals.  How far in most
cases they actually sympathise in the pains and pleasures of others, is
more doubtful, especially with respect to pleasures.  Mr. Buxton, however,
who had excellent means of observation (11.  'Annals and Magazine of
Natural History,' November 1868, p. 382.), states that his macaws, which
lived free in Norfolk, took "an extravagant interest" in a pair with a
nest; and whenever the female left it, she was surrounded by a troop
"screaming horrible acclamations in her honour."  It is often difficult to
judge whether animals have any feeling for the sufferings of others of
their kind.  Who can say what cows feel, when they surround and stare
intently on a dying or dead companion; apparently, however, as Houzeau
remarks, they feel no pity.  That animals sometimes are far from feeling
any sympathy is too certain; for they will expel a wounded animal from the
herd, or gore or worry it to death.  This is almost the blackest fact in
natural history, unless, indeed, the explanation which has been suggested
is true, that their instinct or reason leads them to expel an injured
companion, lest beasts of prey, including man, should be tempted to follow
the troop.  In this case their conduct is not much worse than that of the
North American Indians, who leave their feeble comrades to perish on the
plains; or the Fijians, who, when their parents get old, or fall ill, bury
them alive.  (12.  Sir J. Lubbock, 'Prehistoric Times,' 2nd ed., p. 446.)

Many animals, however, certainly sympathise with each other's distress or
danger.  This is the case even with birds.  Captain Stansbury (13.  As
quoted by Mr. L.H. Morgan, 'The American Beaver,' 1868, p. 272.  Capt.
Stansbury also gives an interesting account of the manner in which a very
young pelican, carried away by a strong stream, was guided and encouraged
in its attempts to reach the shore by half a dozen old birds.) found on a
salt lake in Utah an old and completely blind pelican, which was very fat,
and must have been well fed for a long time by his companions.  Mr. Blyth,
as he informs me, saw Indian crows feeding two or three of their companions
which were blind; and I have heard of an analogous case with the domestic
cock.  We may, if we choose, call these actions instinctive; but such cases
are much too rare for the development of any special instinct.  (14.  As
Mr. Bain states, "effective aid to a sufferer springs from sympathy
proper:"  'Mental and Moral Science,' 1868, p. 245.)  I have myself seen a
dog, who never passed a cat who lay sick in a basket, and was a great
friend of his, without giving her a few licks with his tongue, the surest
sign of kind feeling in a dog.

It must be called sympathy that leads a courageous dog to fly at any one
who strikes his master, as he certainly will.  I saw a person pretending to
beat a lady, who had a very timid little dog on her lap, and the trial had
never been made before; the little creature instantly jumped away, but
after the pretended beating was over, it was really pathetic to see how
perseveringly he tried to lick his mistress's face, and comfort her.  Brehm
(15.  'Thierleben,' B. i. s. 85.) states that when a baboon in confinement
was pursued to be punished, the others tried to protect him.  It must have
been sympathy in the cases above given which led the baboons and
Cercopitheci to defend their young comrades from the dogs and the eagle.  I
will give only one other instance of sympathetic and heroic conduct, in the
case of a little American monkey.  Several years ago a keeper at the
Zoological Gardens shewed me some deep and scarcely healed wounds on the
nape of his own neck, inflicted on him, whilst kneeling on the floor, by a
fierce baboon.  The little American monkey, who was a warm friend of this
keeper, lived in the same large compartment, and was dreadfully afraid of
the great baboon.  Nevertheless, as soon as he saw his friend in peril, he
rushed to the rescue, and by screams and bites so distracted the baboon
that the man was able to escape, after, as the surgeon thought, running
great risk of his life.

Besides love and sympathy, animals exhibit other qualities connected with
the social instincts, which in us would be called moral; and I agree with
Agassiz (16.  'De l'Espece et de la Classe,' 1869, p. 97.) that dogs
possess something very like a conscience.

Dogs possess some power of self-command, and this does not appear to be
wholly the result of fear.  As Braubach (17.  'Die Darwin'sche Art-Lehre,'
1869, s. 54.) remarks, they will refrain from stealing food in the absence
of their master.  They have long been accepted as the very type of fidelity
and obedience.  But the elephant is likewise very faithful to his driver or
keeper, and probably considers him as the leader of the herd.  Dr. Hooker
informs me that an elephant, which he was riding in India, became so deeply
bogged that he remained stuck fast until the next day, when he was
extricated by men with ropes.  Under such circumstances elephants will
seize with their trunks any object, dead or alive, to place under their
knees, to prevent their sinking deeper in the mud; and the driver was
dreadfully afraid lest the animal should have seized Dr. Hooker and crushed
him to death.  But the driver himself, as Dr. Hooker was assured, ran no
risk.  This forbearance under an emergency so dreadful for a heavy animal,
is a wonderful proof of noble fidelity.  (18.  See also Hooker's 'Himalayan
Journals,' vol. ii. 1854, p. 333.)

All animals living in a body, which defend themselves or attack their
enemies in concert, must indeed be in some degree faithful to one another;
and those that follow a leader must be in some degree obedient.  When the
baboons in Abyssinia (19.  Brehm, 'Thierleben,' B. i. s. 76.) plunder a
garden, they silently follow their leader; and if an imprudent young animal
makes a noise, he receives a slap from the others to teach him silence and
obedience.  Mr. Galton, who has had excellent opportunities for observing
the half-wild cattle in S. Africa, says (20.  See his extremely interesting
paper on 'Gregariousness in Cattle, and in Man,' 'Macmillan's Magazine,'
Feb. 1871, p. 353.), that they cannot endure even a momentary separation
from the herd.  They are essentially slavish, and accept the common
determination, seeking no better lot than to be led by any one ox who has
enough self-reliance to accept the position.  The men who break in these
animals for harness, watch assiduously for those who, by grazing apart,
shew a self-reliant disposition, and these they train as fore-oxen.  Mr.
Galton adds that such animals are rare and valuable; and if many were born
they would soon be eliminated, as lions are always on the look-out for the
individuals which wander from the herd.

With respect to the impulse which leads certain animals to associate
together, and to aid one another in many ways, we may infer that in most
cases they are impelled by the same sense of satisfaction or pleasure which
they experience in performing other instinctive actions; or by the same
sense of dissatisfaction as when other instinctive actions are checked.  We
see this in innumerable instances, and it is illustrated in a striking
manner by the acquired instincts of our domesticated animals; thus a young
shepherd-dog delights in driving and running round a flock of sheep, but
not in worrying them; a young fox-hound delights in hunting a fox, whilst
some other kinds of dogs, as I have witnessed, utterly disregard foxes.
What a strong feeling of inward satisfaction must impel a bird, so full of
activity, to brood day after day over her eggs.  Migratory birds are quite
miserable if stopped from migrating; perhaps they enjoy starting on their
long flight; but it is hard to believe that the poor pinioned goose,
described by Audubon, which started on foot at the proper time for its
journey of probably more than a thousand miles, could have felt any joy in
doing so.  Some instincts are determined solely by painful feelings, as by
fear, which leads to self-preservation, and is in some cases directed
towards special enemies.  No one, I presume, can analyse the sensations of
pleasure or pain.  In many instances, however, it is probable that
instincts are persistently followed from the mere force of inheritance,
without the stimulus of either pleasure or pain.  A young pointer, when it
first scents game, apparently cannot help pointing.  A squirrel in a cage
who pats the nuts which it cannot eat, as if to bury them in the ground,
can hardly be thought to act thus, either from pleasure or pain.  Hence the
common assumption that men must be impelled to every action by experiencing
some pleasure or pain may be erroneous.  Although a habit may be blindly
and implicitly followed, independently of any pleasure or pain felt at the
moment, yet if it be forcibly and abruptly checked, a vague sense of
dissatisfaction is generally experienced.

It has often been assumed that animals were in the first place rendered
social, and that they feel as a consequence uncomfortable when separated
from each other, and comfortable whilst together; but it is a more probable
view that these sensations were first developed, in order that those
animals which would profit by living in society, should be induced to live
together, in the same manner as the sense of hunger and the pleasure of
eating were, no doubt, first acquired in order to induce animals to eat.
The feeling of pleasure from society is probably an extension of the
parental or filial affections, since the social instinct seems to be
developed by the young remaining for a long time with their parents; and
this extension may be attributed in part to habit, but chiefly to natural
selection.  With those animals which were benefited by living in close
association, the individuals which took the greatest pleasure in society
would best escape various dangers, whilst those that cared least for their
comrades, and lived solitary, would perish in greater numbers.  With
respect to the origin of the parental and filial affections, which
apparently lie at the base of the social instincts, we know not the steps
by which they have been gained; but we may infer that it has been to a
large extent through natural selection.  So it has almost certainly been
with the unusual and opposite feeling of hatred between the nearest
relations, as with the worker-bees which kill their brother drones, and
with the queen-bees which kill their daughter-queens; the desire to destroy
their nearest relations having been in this case of service to the
community.  Parental affection, or some feeling which replaces it, has been
developed in certain animals extremely low in the scale, for example, in
star-fishes and spiders.  It is also occasionally present in a few members
alone in a whole group of animals, as in the genus Forficula, or earwigs.

The all-important emotion of sympathy is distinct from that of love.  A
mother may passionately love her sleeping and passive infant, but she can
hardly at such times be said to feel sympathy for it.  The love of a man
for his dog is distinct from sympathy, and so is that of a dog for his
master.  Adam Smith formerly argued, as has Mr. Bain recently, that the
basis of sympathy lies in our strong retentiveness of former states of pain
or pleasure.  Hence, "the sight of another person enduring hunger, cold,
fatigue, revives in us some recollection of these states, which are painful
even in idea."  We are thus impelled to relieve the sufferings of another,
in order that our own painful feelings may be at the same time relieved.
In like manner we are led to participate in the pleasures of others.  (21.
See the first and striking chapter in Adam Smith's 'Theory of Moral
Sentiments.'  Also 'Mr. Bain's Mental and Moral Science,' 1868, pp. 244,
and 275-282.  Mr. Bain states, that, "sympathy is, indirectly, a source of
pleasure to the sympathiser"; and he accounts for this through reciprocity.
He remarks that "the person benefited, or others in his stead, may make up,
by sympathy and good offices returned, for all the sacrifice."  But if, as
appears to be the case, sympathy is strictly an instinct, its exercise
would give direct pleasure, in the same manner as the exercise, as before
remarked, of almost every other instinct.)  But I cannot see how this view
explains the fact that sympathy is excited, in an immeasurably stronger
degree, by a beloved, than by an indifferent person.  The mere sight of
suffering, independently of love, would suffice to call up in us vivid
recollections and associations.  The explanation may lie in the fact that,
with all animals, sympathy is directed solely towards the members of the
same community, and therefore towards known, and more or less beloved
members, but not to all the individuals of the same species.  This fact is
not more surprising than that the fears of many animals should be directed
against special enemies.  Species which are not social, such as lions and
tigers, no doubt feel sympathy for the suffering of their own young, but
not for that of any other animal.  With mankind, selfishness, experience,
and imitation, probably add, as Mr. Bain has shewn, to the power of
sympathy; for we are led by the hope of receiving good in return to perform
acts of sympathetic kindness to others; and sympathy is much strengthened
by habit.  In however complex a manner this feeling may have originated, as
it is one of high importance to all those animals which aid and defend one
another, it will have been increased through natural selection; for those
communities, which included the greatest number of the most sympathetic
members, would flourish best, and rear the greatest number of offspring.

It is, however, impossible to decide in many cases whether certain social
instincts have been acquired through natural selection, or are the indirect
result of other instincts and faculties, such as sympathy, reason,
experience, and a tendency to imitation; or again, whether they are simply
the result of long-continued habit.  So remarkable an instinct as the
placing sentinels to warn the community of danger, can hardly have been the
indirect result of any of these faculties; it must, therefore, have been
directly acquired.  On the other hand, the habit followed by the males of
some social animals of defending the community, and of attacking their
enemies or their prey in concert, may perhaps have originated from mutual
sympathy; but courage, and in most cases strength, must have been
previously acquired, probably through natural selection.

Of the various instincts and habits, some are much stronger than others;
that is, some either give more pleasure in their performance, and more
distress in their prevention, than others; or, which is probably quite as
important, they are, through inheritance, more persistently followed,
without exciting any special feeling of pleasure or pain.  We are ourselves
conscious that some habits are much more difficult to cure or change than
others.  Hence a struggle may often be observed in animals between
different instincts, or between an instinct and some habitual disposition;
as when a dog rushes after a hare, is rebuked, pauses, hesitates, pursues
again, or returns ashamed to his master; or as between the love of a female
dog for her young puppies and for her master,--for she may be seen to slink
away to them, as if half ashamed of not accompanying her master.  But the
most curious instance known to me of one instinct getting the better of
another, is the migratory instinct conquering the maternal instinct.  The
former is wonderfully strong; a confined bird will at the proper season
beat her breast against the wires of her cage, until it is bare and bloody.
It causes young salmon to leap out of the fresh water, in which they could
continue to exist, and thus unintentionally to commit suicide.  Every one
knows how strong the maternal instinct is, leading even timid birds to face
great danger, though with hesitation, and in opposition to the instinct of
self-preservation.  Nevertheless, the migratory instinct is so powerful,
that late in the autumn swallows, house-martins, and swifts frequently
desert their tender young, leaving them to perish miserably in their nests.
(22.  This fact, the Rev. L. Jenyns states (see his edition of 'White's
Nat. Hist. of Selborne,' 1853, p. 204) was first recorded by the
illustrious Jenner, in 'Phil. Transact.' 1824, and has since been confirmed
by several observers, especially by Mr. Blackwall.  This latter careful
observer examined, late in the autumn, during two years, thirty-six nests;
he found that twelve contained young dead birds, five contained eggs on the
point of being hatched, and three, eggs not nearly hatched.  Many birds,
not yet old enough for a prolonged flight, are likewise deserted and left
behind.  See Blackwall, 'Researches in Zoology,' 1834, pp. 108, 118.  For
some additional evidence, although this is not wanted, see Leroy, 'Lettres
Phil.' 1802, p. 217.  For Swifts, Gould's 'Introduction to the Birds of
Great Britain,' 1823, p. 5.  Similar cases have been observed in Canada by
Mr. Adams; 'Pop. Science Review,' July 1873, p. 283.)

We can perceive that an instinctive impulse, if it be in any way more
beneficial to a species than some other or opposed instinct, would be
rendered the more potent of the two through natural selection; for the
individuals which had it most strongly developed would survive in larger
numbers.  Whether this is the case with the migratory in comparison with
the maternal instinct, may be doubted.  The great persistence, or steady
action of the former at certain seasons of the year during the whole day,
may give it for a time paramount force.

MAN A SOCIAL ANIMAL.

Every one will admit that man is a social being.  We see this in his
dislike of solitude, and in his wish for society beyond that of his own
family.  Solitary confinement is one of the severest punishments which can
be inflicted.  Some authors suppose that man primevally lived in single
families; but at the present day, though single families, or only two or
three together, roam the solitudes of some savage lands, they always, as
far as I can discover, hold friendly relations with other families
inhabiting the same district.  Such families occasionally meet in council,
and unite for their common defence.  It is no argument against savage man
being a social animal, that the tribes inhabiting adjacent districts are
almost always at war with each other; for the social instincts never extend
to all the individuals of the same species.  Judging from the analogy of
the majority of the Quadrumana, it is probable that the early ape-like
progenitors of man were likewise social; but this is not of much importance
for us.  Although man, as he now exists, has few special instincts, having
lost any which his early progenitors may have possessed, this is no reason
why he should not have retained from an extremely remote period some degree
of instinctive love and sympathy for his fellows.  We are indeed all
conscious that we do possess such sympathetic feelings (23.  Hume remarks
('An Enquiry Concerning the Principles of Morals,' edit. of 1751, p. 132),
"There seems a necessity for confessing that the happiness and misery of
others are not spectacles altogether indifferent to us, but that the view
of the former...communicates a secret joy; the appearance of the latter...
throws a melancholy damp over the imagination."); but our consciousness
does not tell us whether they are instinctive, having originated long ago
in the same manner as with the lower animals, or whether they have been
acquired by each of us during our early years.  As man is a social animal,
it is almost certain that he would inherit a tendency to be faithful to his
comrades, and obedient to the leader of his tribe; for these qualities are
common to most social animals.  He would consequently possess some capacity
for self-command.  He would from an inherited tendency be willing to
defend, in concert with others, his fellow-men; and would be ready to aid
them in any way, which did not too greatly interfere with his own welfare
or his own strong desires.

The social animals which stand at the bottom of the scale are guided almost
exclusively, and those which stand higher in the scale are largely guided,
by special instincts in the aid which they give to the members of the same
community; but they are likewise in part impelled by mutual love and
sympathy, assisted apparently by some amount of reason.  Although man, as
just remarked, has no special instincts to tell him how to aid his fellow-
men, he still has the impulse, and with his improved intellectual faculties
would naturally be much guided in this respect by reason and experience.
Instinctive sympathy would also cause him to value highly the approbation
of his fellows; for, as Mr. Bain has clearly shewn (24.  'Mental and Moral
Science,' 1868, p. 254.), the love of praise and the strong feeling of
glory, and the still stronger horror of scorn and infamy, "are due to the
workings of sympathy."  Consequently man would be influenced in the highest
degree by the wishes, approbation, and blame of his fellow-men, as
expressed by their gestures and language.  Thus the social instincts, which
must have been acquired by man in a very rude state, and probably even by
his early ape-like progenitors, still give the impulse to some of his best
actions; but his actions are in a higher degree determined by the expressed
wishes and judgment of his fellow-men, and unfortunately very often by his
own strong selfish desires.  But as love, sympathy and self-command become
strengthened by habit, and as the power of reasoning becomes clearer, so
that man can value justly the judgments of his fellows, he will feel
himself impelled, apart from any transitory pleasure or pain, to certain
lines of conduct.  He might then declare--not that any barbarian or
uncultivated man could thus think--I am the supreme judge of my own
conduct, and in the words of Kant, I will not in my own person violate the
dignity of humanity.

THE MORE ENDURING SOCIAL INSTINCTS CONQUER THE LESS PERSISTENT INSTINCTS.

We have not, however, as yet considered the main point, on which, from our
present point of view, the whole question of the moral sense turns.  Why
should a man feel that he ought to obey one instinctive desire rather than
another?  Why is he bitterly regretful, if he has yielded to a strong sense
of self-preservation, and has not risked his life to save that of a fellow-
creature? or why does he regret having stolen food from hunger?

It is evident in the first place, that with mankind the instinctive
impulses have different degrees of strength; a savage will risk his own
life to save that of a member of the same community, but will be wholly
indifferent about a stranger:  a young and timid mother urged by the
maternal instinct will, without a moment's hesitation, run the greatest
danger for her own infant, but not for a mere fellow-creature.
Nevertheless many a civilised man, or even boy, who never before risked his
life for another, but full of courage and sympathy, has disregarded the
instinct of self-preservation, and plunged at once into a torrent to save a
drowning man, though a stranger.  In this case man is impelled by the same
instinctive motive, which made the heroic little American monkey, formerly
described, save his keeper, by attacking the great and dreaded baboon.
Such actions as the above appear to be the simple result of the greater
strength of the social or maternal instincts rather than that of any other
instinct or motive; for they are performed too instantaneously for
reflection, or for pleasure or pain to be felt at the time; though, if
prevented by any cause, distress or even misery might be felt.  In a timid
man, on the other hand, the instinct of self-preservation might be so
strong, that he would be unable to force himself to run any such risk,
perhaps not even for his own child.

I am aware that some persons maintain that actions performed impulsively,
as in the above cases, do not come under the dominion of the moral sense,
and cannot be called moral.  They confine this term to actions done
deliberately, after a victory over opposing desires, or when prompted by
some exalted motive.  But it appears scarcely possible to draw any clear
line of distinction of this kind.  (25.  I refer here to the distinction
between what has been called MATERIAL and FORMAL morality.  I am glad to
find that Professor Huxley ('Critiques and Addresses,' 1873, p. 287) takes
the same view on this subject as I do.  Mr. Leslie Stephen remarks ('Essays
on Freethinking and Plain Speaking,' 1873, p. 83), "the metaphysical
distinction, between material and formal morality is as irrelevant as other
such distinctions.")  As far as exalted motives are concerned, many
instances have been recorded of savages, destitute of any feeling of
general benevolence towards mankind, and not guided by any religious
motive, who have deliberately sacrificed their lives as prisoners(26.  I
have given one such case, namely of three Patagonian Indians who preferred
being shot, one after the other, to betraying the plans of their companions
in war ('Journal of Researches,' 1845, p. 103).), rather than betray their
comrades; and surely their conduct ought to be considered as moral.  As far
as deliberation, and the victory over opposing motives are concerned,
animals may be seen doubting between opposed instincts, in rescuing their
offspring or comrades from danger; yet their actions, though done for the
good of others, are not called moral.  Moreover, anything performed very
often by us, will at last be done without deliberation or hesitation, and
can then hardly be distinguished from an instinct; yet surely no one will
pretend that such an action ceases to be moral.  On the contrary, we all
feel that an act cannot be considered as perfect, or as performed in the
most noble manner, unless it be done impulsively, without deliberation or
effort, in the same manner as by a man in whom the requisite qualities are
innate.  He who is forced to overcome his fear or want of sympathy before
he acts, deserves, however, in one way higher credit than the man whose
innate disposition leads him to a good act without effort.  As we cannot
distinguish between motives, we rank all actions of a certain class as
moral, if performed by a moral being.  A moral being is one who is capable
of comparing his past and future actions or motives, and of approving or
disapproving of them.  We have no reason to suppose that any of the lower
animals have this capacity; therefore, when a Newfoundland dog drags a
child out of the water, or a monkey faces danger to rescue its comrade, or
takes charge of an orphan monkey, we do not call its conduct moral.  But in
the case of man, who alone can with certainty be ranked as a moral being,
actions of a certain class are called moral, whether performed
deliberately, after a struggle with opposing motives, or impulsively
through instinct, or from the effects of slowly-gained habit.

But to return to our more immediate subject.  Although some instincts are
more powerful than others, and thus lead to corresponding actions, yet it
is untenable, that in man the social instincts (including the love of
praise and fear of blame) possess greater strength, or have, through long
habit, acquired greater strength than the instincts of self-preservation,
hunger, lust, vengeance, etc.  Why then does man regret, even though trying
to banish such regret, that he has followed the one natural impulse rather
than the other; and why does he further feel that he ought to regret his
conduct?  Man in this respect differs profoundly from the lower animals.
Nevertheless we can, I think, see with some degree of clearness the reason
of this difference.

Man, from the activity of his mental faculties, cannot avoid reflection:
past impressions and images are incessantly and clearly passing through his
mind.  Now with those animals which live permanently in a body, the social
instincts are ever present and persistent.  Such animals are always ready
to utter the danger-signal, to defend the community, and to give aid to
their fellows in accordance with their habits; they feel at all times,
without the stimulus of any special passion or desire, some degree of love
and sympathy for them; they are unhappy if long separated from them, and
always happy to be again in their company.  So it is with ourselves.  Even
when we are quite alone, how often do we think with pleasure or pain of
what others think of us,--of their imagined approbation or disapprobation;
and this all follows from sympathy, a fundamental element of the social
instincts.  A man who possessed no trace of such instincts would be an
unnatural monster.  On the other hand, the desire to satisfy hunger, or any
passion such as vengeance, is in its nature temporary, and can for a time
be fully satisfied.  Nor is it easy, perhaps hardly possible, to call up
with complete vividness the feeling, for instance, of hunger; nor indeed,
as has often been remarked, of any suffering.  The instinct of self-
preservation is not felt except in the presence of danger; and many a
coward has thought himself brave until he has met his enemy face to face.
The wish for another man's property is perhaps as persistent a desire as
any that can be named; but even in this case the satisfaction of actual
possession is generally a weaker feeling than the desire:  many a thief, if
not a habitual one, after success has wondered why he stole some article.
(27. Enmity or hatred seems also to be a highly persistent feeling, perhaps
more so than any other that can be named.  Envy is defined as hatred of
another for some excellence or success; and Bacon insists (Essay ix.), "Of
all other affections envy is the most importune and continual."  Dogs are
very apt to hate both strange men and strange dogs, especially if they live
near at hand, but do not belong to the same family, tribe, or clan; this
feeling would thus seem to be innate, and is certainly a most persistent
one.  It seems to be the complement and converse of the true social
instinct.  From what we hear of savages, it would appear that something of
the same kind holds good with them.  If this be so, it would be a small
step in any one to transfer such feelings to any member of the same tribe
if he had done him an injury and had become his enemy.  Nor is it probable
that the primitive conscience would reproach a man for injuring his enemy;
rather it would reproach him, if he had not revenged himself.  To do good
in return for evil, to love your enemy, is a height of morality to which it
may be doubted whether the social instincts would, by themselves, have ever
led us.  It is necessary that these instincts, together with sympathy,
should have been highly cultivated and extended by the aid of reason,
instruction, and the love or fear of God, before any such golden rule would
ever be thought of and obeyed.)

A man cannot prevent past impressions often repassing through his mind; he
will thus be driven to make a comparison between the impressions of past
hunger, vengeance satisfied, or danger shunned at other men's cost, with
the almost ever-present instinct of sympathy, and with his early knowledge
of what others consider as praiseworthy or blameable.  This knowledge
cannot be banished from his mind, and from instinctive sympathy is esteemed
of great moment.  He will then feel as if he had been baulked in following
a present instinct or habit, and this with all animals causes
dissatisfaction, or even misery.

The above case of the swallow affords an illustration, though of a reversed
nature, of a temporary though for the time strongly persistent instinct
conquering another instinct, which is usually dominant over all others.  At
the proper season these birds seem all day long to be impressed with the
desire to migrate; their habits change; they become restless, are noisy and
congregate in flocks.  Whilst the mother-bird is feeding, or brooding over
her nestlings, the maternal instinct is probably stronger than the
migratory; but the instinct which is the more persistent gains the victory,
and at last, at a moment when her young ones are not in sight, she takes
flight and deserts them.  When arrived at the end of her long journey, and
the migratory instinct has ceased to act, what an agony of remorse the bird
would feel, if, from being endowed with great mental activity, she could
not prevent the image constantly passing through her mind, of her young
ones perishing in the bleak north from cold and hunger.

At the moment of action, man will no doubt be apt to follow the stronger
impulse; and though this may occasionally prompt him to the noblest deeds,
it will more commonly lead him to gratify his own desires at the expense of
other men.  But after their gratification when past and weaker impressions
are judged by the ever-enduring social instinct, and by his deep regard for
the good opinion of his fellows, retribution will surely come.  He will
then feel remorse, repentance, regret, or shame; this latter feeling,
however, relates almost exclusively to the judgment of others.  He will
consequently resolve more or less firmly to act differently for the future;
and this is conscience; for conscience looks backwards, and serves as a
guide for the future.

The nature and strength of the feelings which we call regret, shame,
repentance or remorse, depend apparently not only on the strength of the
violated instinct, but partly on the strength of the temptation, and often
still more on the judgment of our fellows.  How far each man values the
appreciation of others, depends on the strength of his innate or acquired
feeling of sympathy; and on his own capacity for reasoning out the remote
consequences of his acts.  Another element is most important, although not
necessary, the reverence or fear of the Gods, or Spirits believed in by
each man:  and this applies especially in cases of remorse.  Several
critics have objected that though some slight regret or repentance may be
explained by the view advocated in this chapter, it is impossible thus to
account for the soul-shaking feeling of remorse.  But I can see little
force in this objection.  My critics do not define what they mean by
remorse, and I can find no definition implying more than an overwhelming
sense of repentance.  Remorse seems to bear the same relation to
repentance, as rage does to anger, or agony to pain.  It is far from
strange that an instinct so strong and so generally admired, as maternal
love, should, if disobeyed, lead to the deepest misery, as soon as the
impression of the past cause of disobedience is weakened.  Even when an
action is opposed to no special instinct, merely to know that our friends
and equals despise us for it is enough to cause great misery.  Who can
doubt that the refusal to fight a duel through fear has caused many men an
agony of shame?  Many a Hindoo, it is said, has been stirred to the bottom
of his soul by having partaken of unclean food.  Here is another case of
what must, I think, be called remorse.  Dr. Landor acted as a magistrate in
West Australia, and relates (28.  'Insanity in Relation to Law,' Ontario,
United States, 1871, p. 1.), that a native on his farm, after losing one of
his wives from disease, came and said that, "he was going to a distant
tribe to spear a woman, to satisfy his sense of duty to his wife.  I told
him that if he did so, I would send him to prison for life.  He remained
about the farm for some months, but got exceedingly thin, and complained
that he could not rest or eat, that his wife's spirit was haunting him,
because he had not taken a life for hers.  I was inexorable, and assured
him that nothing should save him if he did."  Nevertheless the man
disappeared for more than a year, and then returned in high condition; and
his other wife told Dr. Landor that her husband had taken the life of a
woman belonging to a distant tribe; but it was impossible to obtain legal
evidence of the act.  The breach of a rule held sacred by the tribe, will
thus, as it seems, give rise to the deepest feelings,--and this quite apart
from the social instincts, excepting in so far as the rule is grounded on
the judgment of the community.  How so many strange superstitions have
arisen throughout the world we know not; nor can we tell how some real and
great crimes, such as incest, have come to be held in an abhorrence (which
is not however quite universal) by the lowest savages.  It is even doubtful
whether in some tribes incest would be looked on with greater horror, than
would the marriage of a man with a woman bearing the same name, though not
a relation.  "To violate this law is a crime which the Australians hold in
the greatest abhorrence, in this agreeing exactly with certain tribes of
North America.  When the question is put in either district, is it worse to
kill a girl of a foreign tribe, or to marry a girl of one's own, an answer
just opposite to ours would be given without hesitation."  (29.  E.B.
Tylor, in 'Contemporary Review,' April 1873, p. 707.)  We may, therefore,
reject the belief, lately insisted on by some writers, that the abhorrence
of incest is due to our possessing a special God-implanted conscience.  On
the whole it is intelligible, that a man urged by so powerful a sentiment
as remorse, though arising as above explained, should be led to act in a
manner, which he has been taught to believe serves as an expiation, such as
delivering himself up to justice.

Man prompted by his conscience, will through long habit acquire such
perfect self-command, that his desires and passions will at last yield
instantly and without a struggle to his social sympathies and instincts,
including his feeling for the judgment of his fellows.  The still hungry,
or the still revengeful man will not think of stealing food, or of wreaking
his vengeance.  It is possible, or as we shall hereafter see, even
probable, that the habit of self-command may, like other habits, be
inherited.  Thus at last man comes to feel, through acquired and perhaps
inherited habit, that it is best for him to obey his more persistent
impulses.  The imperious word "ought" seems merely to imply the
consciousness of the existence of a rule of conduct, however it may have
originated.  Formerly it must have been often vehemently urged that an
insulted gentleman OUGHT to fight a duel.  We even say that a pointer OUGHT
to point, and a retriever to retrieve game.  If they fail to do so, they
fail in their duty and act wrongly.

If any desire or instinct leading to an action opposed to the good of
others still appears, when recalled to mind, as strong as, or stronger
than, the social instinct, a man will feel no keen regret at having
followed it; but he will be conscious that if his conduct were known to his
fellows, it would meet with their disapprobation; and few are so destitute
of sympathy as not to feel discomfort when this is realised.  If he has no
such sympathy, and if his desires leading to bad actions are at the time
strong, and when recalled are not over-mastered by the persistent social
instincts, and the judgment of others, then he is essentially a bad man
(30.  Dr. Prosper Despine, in his Psychologie Naturelle, 1868 (tom. i. p.
243; tom. ii. p. 169) gives many curious cases of the worst criminals, who
apparently have been entirely destitute of conscience.); and the sole
restraining motive left is the fear of punishment, and the conviction that
in the long run it would be best for his own selfish interests to regard
the good of others rather than his own.

It is obvious that every one may with an easy conscience gratify his own
desires, if they do not interfere with his social instincts, that is with
the good of others; but in order to be quite free from self-reproach, or at
least of anxiety, it is almost necessary for him to avoid the
disapprobation, whether reasonable or not, of his fellow-men.  Nor must he
break through the fixed habits of his life, especially if these are
supported by reason; for if he does, he will assuredly feel
dissatisfaction.  He must likewise avoid the reprobation of the one God or
gods in whom, according to his knowledge or superstition, he may believe;
but in this case the additional fear of divine punishment often supervenes.

THE STRICTLY SOCIAL VIRTUES AT FIRST ALONE REGARDED.

The above view of the origin and nature of the moral sense, which tells us
what we ought to do, and of the conscience which reproves us if we disobey
it, accords well with what we see of the early and undeveloped condition of
this faculty in mankind.  The virtues which must be practised, at least
generally, by rude men, so that they may associate in a body, are those
which are still recognised as the most important.  But they are practised
almost exclusively in relation to the men of the same tribe; and their
opposites are not regarded as crimes in relation to the men of other
tribes.  No tribe could hold together if murder, robbery, treachery, etc.,
were common; consequently such crimes within the limits of the same tribe
"are branded with everlasting infamy" (31.  See an able article in the
'North British Review,' 1867, p. 395.  See also Mr. W. Bagehot's articles
on the Importance of Obedience and Coherence to Primitive Man, in the
'Fortnightly Review,' 1867, p. 529, and 1868, p. 457, etc.); but excite no
such sentiment beyond these limits.  A North-American Indian is well
pleased with himself, and is honoured by others, when he scalps a man of
another tribe; and a Dyak cuts off the head of an unoffending person, and
dries it as a trophy.  The murder of infants has prevailed on the largest
scale throughout the world (32.  The fullest account which I have met with
is by Dr. Gerland, in his 'Ueber den Aussterben der Naturvoelker,' 1868; but
I shall have to recur to the subject of infanticide in a future chapter.),
and has met with no reproach; but infanticide, especially of females, has
been thought to be good for the tribe, or at least not injurious.  Suicide
during former times was not generally considered as a crime (33.  See the
very interesting discussion on suicide in Lecky's 'History of European
Morals,' vol. i. 1869, p. 223.  With respect to savages, Mr. Winwood Reade
informs me that the negroes of West Africa often commit suicide.  It is
well known how common it was amongst the miserable aborigines of South
America after the Spanish conquest.  For New Zealand, see the voyage of the
Novara, and for the Aleutian Islands, Mueller, as quoted by Houzeau, 'Les
Facultes Mentales,' etc., tom. ii. p. 136.), but rather, from the courage
displayed, as an honourable act; and it is still practised by some semi-
civilised and savage nations without reproach, for it does not obviously
concern others of the tribe.  It has been recorded that an Indian Thug
conscientiously regretted that he had not robbed and strangled as many
travellers as did his father before him.  In a rude state of civilisation
the robbery of strangers is, indeed, generally considered as honourable.


Slavery, although in some ways beneficial during ancient times (34.  See
Mr. Bagehot, 'Physics and Politics,' 1872, p. 72.), is a great crime; yet
it was not so regarded until quite recently, even by the most civilised
nations.  And this was especially the case, because the slaves belonged in
general to a race different from that of their masters.  As barbarians do
not regard the opinion of their women, wives are commonly treated like
slaves.  Most savages are utterly indifferent to the sufferings of
strangers, or even delight in witnessing them.  It is well known that the
women and children of the North-American Indians aided in torturing their
enemies.  Some savages take a horrid pleasure in cruelty to animals (35.
See, for instance, Mr. Hamilton's account of the Kaffirs, 'Anthropological
Review,' 1870, p. xv.), and humanity is an unknown virtue.  Nevertheless,
besides the family affections, kindness is common, especially during
sickness, between the members of the same tribe, and is sometimes extended
beyond these limits.  Mungo Park's touching account of the kindness of the
negro women of the interior to him is well known.  Many instances could be
given of the noble fidelity of savages towards each other, but not to
strangers; common experience justifies the maxim of the Spaniard, "Never,
never trust an Indian."  There cannot be fidelity without truth; and this
fundamental virtue is not rare between the members of the same tribe:  thus
Mungo Park heard the negro women teaching their young children to love the
truth.  This, again, is one of the virtues which becomes so deeply rooted
in the mind, that it is sometimes practised by savages, even at a high
cost, towards strangers; but to lie to your enemy has rarely been thought a
sin, as the history of modern diplomacy too plainly shews.  As soon as a
tribe has a recognised leader, disobedience becomes a crime, and even
abject submission is looked at as a sacred virtue.

As during rude times no man can be useful or faithful to his tribe without
courage, this quality has universally been placed in the highest rank; and
although in civilised countries a good yet timid man may be far more useful
to the community than a brave one, we cannot help instinctively honouring
the latter above a coward, however benevolent.  Prudence, on the other
hand, which does not concern the welfare of others, though a very useful
virtue, has never been highly esteemed.  As no man can practise the virtues
necessary for the welfare of his tribe without self-sacrifice, self-
command, and the power of endurance, these qualities have been at all times
highly and most justly valued.  The American savage voluntarily submits to
the most horrid tortures without a groan, to prove and strengthen his
fortitude and courage; and we cannot help admiring him, or even an Indian
Fakir, who, from a foolish religious motive, swings suspended by a hook
buried in his flesh.

The other so-called self-regarding virtues, which do not obviously, though
they may really, affect the welfare of the tribe, have never been esteemed
by savages, though now highly appreciated by civilised nations.  The
greatest intemperance is no reproach with savages.  Utter licentiousness,
and unnatural crimes, prevail to an astounding extent.  (36.  Mr. M'Lennan
has given ('Primitive Marriage,' 1865, p. 176) a good collection of facts
on this head.)  As soon, however, as marriage, whether polygamous, or
monogamous, becomes common, jealousy will lead to the inculcation of female
virtue; and this, being honoured, will tend to spread to the unmarried
females.  How slowly it spreads to the male sex, we see at the present day.
Chastity eminently requires self-command; therefore it has been honoured
from a very early period in the moral history of civilised man.  As a
consequence of this, the senseless practice of celibacy has been ranked
from a remote period as a virtue. (38.  Lecky, 'History of European
Morals,' vol. i. 1869, p. 109.)  The hatred of indecency, which appears to
us so natural as to be thought innate, and which is so valuable an aid to
chastity, is a modern virtue, appertaining exclusively, as Sir G. Staunton
remarks (38.  'Embassy to China,' vol. ii. p. 348.), to civilised life.
This is shewn by the ancient religious rites of various nations, by the
drawings on the walls of Pompeii, and by the practices of many savages.

We have now seen that actions are regarded by savages, and were probably so
regarded by primeval man, as good or bad, solely as they obviously affect
the welfare of the tribe,--not that of the species, nor that of an
individual member of the tribe.  This conclusion agrees well with the
belief that the so-called moral sense is aboriginally derived from the
social instincts, for both relate at first exclusively to the community.

The chief causes of the low morality of savages, as judged by our standard,
are, firstly, the confinement of sympathy to the same tribe.  Secondly,
powers of reasoning insufficient to recognise the bearing of many virtues,
especially of the self-regarding virtues, on the general welfare of the
tribe.  Savages, for instance, fail to trace the multiplied evils
consequent on a want of temperance, chastity, etc.  And, thirdly, weak
power of self-command; for this power has not been strengthened through
long-continued, perhaps inherited, habit, instruction and religion.

I have entered into the above details on the immorality of savages (39.
See on this subject copious evidence in Chap. vii. of Sir J. Lubbock,
'Origin of Civilisation,' 1870.), because some authors have recently taken
a high view of their moral nature, or have attributed most of their crimes
to mistaken benevolence. (40.  For instance Lecky, 'History of European
Morals,' vol. i. p. 124.)  These authors appear to rest their conclusion on
savages possessing those virtues which are serviceable, or even necessary,
for the existence of the family and of the tribe,--qualities which they
undoubtedly do possess, and often in a high degree.

CONCLUDING REMARKS.

It was assumed formerly by philosophers of the derivative (41.  This term
is used in an able article in the 'Westminster Review,' Oct. 1869, p. 498.
For the "Greatest happiness principle," see J.S. Mill, 'Utilitarianism,' p.
17.) school of morals that the foundation of morality lay in a form of
Selfishness; but more recently the "Greatest happiness principle" has been
brought prominently forward.  It is, however, more correct to speak of the
latter principle as the standard, and not as the motive of conduct.
Nevertheless, all the authors whose works I have consulted, with a few
exceptions (42.  Mill recognises ('System of Logic,' vol. ii. p. 422) in
the clearest manner, that actions may be performed through habit without
the anticipation of pleasure.  Mr. H. Sidgwick also, in his Essay on
Pleasure and Desire ('The Contemporary Review,' April 1872, p. 671),
remarks:  "To sum up, in contravention of the doctrine that our conscious
active impulses are always directed towards the production of agreeable
sensations in ourselves, I would maintain that we find everywhere in
consciousness extra-regarding impulse, directed towards something that is
not pleasure; that in many cases the impulse is so far incompatible with
the self-regarding that the two do not easily co-exist in the same moment
of consciousness."  A dim feeling that our impulses do not by any means
always arise from any contemporaneous or anticipated pleasure, has, I
cannot but think, been one chief cause of the acceptance of the intuitive
theory of morality, and of the rejection of the utilitarian or "Greatest
happiness" theory.  With respect to the latter theory the standard and the
motive of conduct have no doubt often been confused, but they are really in
some degree blended.), write as if there must be a distinct motive for
every action, and that this must be associated with some pleasure or
displeasure.  But man seems often to act impulsively, that is from instinct
or long habit, without any consciousness of pleasure, in the same manner as
does probably a bee or ant, when it blindly follows its instincts.  Under
circumstances of extreme peril, as during a fire, when a man endeavours to
save a fellow-creature without a moment's hesitation, he can hardly feel
pleasure; and still less has he time to reflect on the dissatisfaction
which he might subsequently experience if he did not make the attempt.
Should he afterwards reflect over his own conduct, he would feel that there
lies within him an impulsive power widely different from a search after
pleasure or happiness; and this seems to be the deeply planted social
instinct.

In the case of the lower animals it seems much more appropriate to speak of
their social instincts, as having been developed for the general good
rather than for the general happiness of the species.  The term, general
good, may be defined as the rearing of the greatest number of individuals
in full vigour and health, with all their faculties perfect, under the
conditions to which they are subjected.  As the social instincts both of
man and the lower animals have no doubt been developed by nearly the same
steps, it would be advisable, if found practicable, to use the same
definition in both cases, and to take as the standard of morality, the
general good or welfare of the community, rather than the general
happiness; but this definition would perhaps require some limitation on
account of political ethics.

When a man risks his life to save that of a fellow-creature, it seems also
more correct to say that he acts for the general good, rather than for the
general happiness of mankind.  No doubt the welfare and the happiness of
the individual usually coincide; and a contented, happy tribe will flourish
better than one that is discontented and unhappy.  We have seen that even
at an early period in the history of man, the expressed wishes of the
community will have naturally influenced to a large extent the conduct of
each member; and as all wish for happiness, the "greatest happiness
principle" will have become a most important secondary guide and object;
the social instinct, however, together with sympathy (which leads to our
regarding the approbation and disapprobation of others), having served as
the primary impulse and guide.  Thus the reproach is removed of laying the
foundation of the noblest part of our nature in the base principle of
selfishness; unless, indeed, the satisfaction which every animal feels,
when it follows its proper instincts, and the dissatisfaction felt when
prevented, be called selfish.

The wishes and opinions of the members of the same community, expressed at
first orally, but later by writing also, either form the sole guides of our
conduct, or greatly reinforce the social instincts; such opinions, however,
have sometimes a tendency directly opposed to these instincts.  This latter
fact is well exemplified by the LAW OF HONOUR, that is, the law of the
opinion of our equals, and not of all our countrymen.  The breach of this
law, even when the breach is known to be strictly accordant with true
morality, has caused many a man more agony than a real crime.  We recognise
the same influence in the burning sense of shame which most of us have
felt, even after the interval of years, when calling to mind some
accidental breach of a trifling, though fixed, rule of etiquette.  The
judgment of the community will generally be guided by some rude experience
of what is best in the long run for all the members; but this judgment will
not rarely err from ignorance and weak powers of reasoning.  Hence the
strangest customs and superstitions, in complete opposition to the true
welfare and happiness of mankind, have become all-powerful throughout the
world.  We see this in the horror felt by a Hindoo who breaks his caste,
and in many other such cases.  It would be difficult to distinguish between
the remorse felt by a Hindoo who has yielded to the temptation of eating
unclean food, from that felt after committing a theft; but the former would
probably be the more severe.

How so many absurd rules of conduct, as well as so many absurd religious
beliefs, have originated, we do not know; nor how it is that they have
become, in all quarters of the world, so deeply impressed on the mind of
men; but it is worthy of remark that a belief constantly inculcated during
the early years of life, whilst the brain is impressible, appears to
acquire almost the nature of an instinct; and the very essence of an
instinct is that it is followed independently of reason.  Neither can we
say why certain admirable virtues, such as the love of truth, are much more
highly appreciated by some savage tribes than by others (43.  Good
instances are given by Mr. Wallace in 'Scientific Opinion,' Sept. 15, 1869;
and more fully in his 'Contributions to the Theory of Natural Selection,'
1870, p. 353.); nor, again, why similar differences prevail even amongst
highly civilised nations.  Knowing how firmly fixed many strange customs
and superstitions have become, we need feel no surprise that the self-
regarding virtues, supported as they are by reason, should now appear to us
so natural as to be thought innate, although they were not valued by man in
his early condition.

Not withstanding many sources of doubt, man can generally and readily
distinguish between the higher and lower moral rules.  The higher are
founded on the social instincts, and relate to the welfare of others.  They
are supported by the approbation of our fellow-men and by reason.  The
lower rules, though some of them when implying self-sacrifice hardly
deserve to be called lower, relate chiefly to self, and arise from public
opinion, matured by experience and cultivation; for they are not practised
by rude tribes.

As man advances in civilisation, and small tribes are united into larger
communities, the simplest reason would tell each individual that he ought
to extend his social instincts and sympathies to all the members of the
same nation, though personally unknown to him.  This point being once
reached, there is only an artificial barrier to prevent his sympathies
extending to the men of all nations and races.  If, indeed, such men are
separated from him by great differences in appearance or habits, experience
unfortunately shews us how long it is, before we look at them as our
fellow-creatures.  Sympathy beyond the confines of man, that is, humanity
to the lower animals, seems to be one of the latest moral acquisitions.  It
is apparently unfelt by savages, except towards their pets.  How little the
old Romans knew of it is shewn by their abhorrent gladiatorial exhibitions.
The very idea of humanity, as far as I could observe, was new to most of
the Gauchos of the Pampas.  This virtue, one of the noblest with which man
is endowed, seems to arise incidentally from our sympathies becoming more
tender and more widely diffused, until they are extended to all sentient
beings.  As soon as this virtue is honoured and practised by some few men,
it spreads through instruction and example to the young, and eventually
becomes incorporated in public opinion.

The highest possible stage in moral culture is when we recognise that we
ought to control our thoughts, and "not even in inmost thought to think
again the sins that made the past so pleasant to us."  (44.  Tennyson,
Idylls of the King, p. 244.)  Whatever makes any bad action familiar to the
mind, renders its performance by so much the easier.  As Marcus Aurelius
long ago said, "Such as are thy habitual thoughts, such also will be the
character of thy mind; for the soul is dyed by the thoughts."  (45.  'The
Thoughts of the Emperor M. Aurelius Antoninus,'  English translation, 2nd
edit., 1869. p. 112.  Marcus Aurelius was born A.D. 121.)

Our great philosopher, Herbert Spencer, has recently explained his views on
the moral sense.  He says (46.  Letter to Mr. Mill in Bain's 'Mental and
Moral Science,' 1868, p. 722.), "I believe that the experiences of utility
organised and consolidated through all past generations of the human race,
have been producing corresponding modifications, which, by continued
transmission and accumulation, have become in us certain faculties of moral
intuition--certain emotions responding to right and wrong conduct, which
have no apparent basis in the individual experiences of utility."  There is
not the least inherent improbability, as it seems to me, in virtuous
tendencies being more or less strongly inherited; for, not to mention the
various dispositions and habits transmitted by many of our domestic animals
to their offspring, I have heard of authentic cases in which a desire to
steal and a tendency to lie appeared to run in families of the upper ranks;
and as stealing is a rare crime in the wealthy classes, we can hardly
account by accidental coincidence for the tendency occurring in two or
three members of the same family.  If bad tendencies are transmitted, it is
probable that good ones are likewise transmitted.  That the state of the
body by affecting the brain, has great influence on the moral tendencies is
known to most of those who have suffered from chronic derangements of the
digestion or liver.  The same fact is likewise shewn by the "perversion or
destruction of the moral sense being often one of the earliest symptoms of
mental derangement" (47.  Maudsley, 'Body and Mind,' 1870, p. 60.); and
insanity is notoriously often inherited.  Except through the principle of
the transmission of moral tendencies, we cannot understand the differences
believed to exist in this respect between the various races of mankind.

Even the partial transmission of virtuous tendencies would be an immense
assistance to the primary impulse derived directly and indirectly from the
social instincts.  Admitting for a moment that virtuous tendencies are
inherited, it appears probable, at least in such cases as chastity,
temperance, humanity to animals, etc., that they become first impressed on
the mental organization through habit, instruction and example, continued
during several generations in the same family, and in a quite subordinate
degree, or not at all, by the individuals possessing such virtues having
succeeded best in the struggle for life.  My chief source of doubt with
respect to any such inheritance, is that senseless customs, superstitions,
and tastes, such as the horror of a Hindoo for unclean food, ought on the
same principle to be transmitted.  I have not met with any evidence in
support of the transmission of superstitious customs or senseless habits,
although in itself it is perhaps not less probable than that animals should
acquire inherited tastes for certain kinds of food or fear of certain foes.

Finally the social instincts, which no doubt were acquired by man as by the
lower animals for the good of the community, will from the first have given
to him some wish to aid his fellows, some feeling of sympathy, and have
compelled him to regard their approbation and disapprobation.  Such
impulses will have served him at a very early period as a rude rule of
right and wrong.  But as man gradually advanced in intellectual power, and
was enabled to trace the more remote consequences of his actions; as he
acquired sufficient knowledge to reject baneful customs and superstitions;
as he regarded more and more, not only the welfare, but the happiness of
his fellow-men; as from habit, following on beneficial experience,
instruction and example, his sympathies became more tender and widely
diffused, extending to men of all races, to the imbecile, maimed, and other
useless members of society, and finally to the lower animals,--so would the
standard of his morality rise higher and higher.  And it is admitted by
moralists of the derivative school and by some intuitionists, that the
standard of morality has risen since an early period in the history of man.
(48.  A writer in the 'North British Review' (July 1869, p. 531), well
capable of forming a sound judgment, expresses himself strongly in favour
of this conclusion.  Mr. Lecky ('History of Morals,' vol. i. p. 143) seems
to a certain extent to coincide therein.)

As a struggle may sometimes be seen going on between the various instincts
of the lower animals, it is not surprising that there should be a struggle
in man between his social instincts, with their derived virtues, and his
lower, though momentarily stronger impulses or desires.  This, as Mr.
Galton (49.  See his remarkable work on 'Hereditary Genius,' 1869, p. 349.
The Duke of Argyll ('Primeval Man,' 1869, p. 188) has some good remarks on
the contest in man's nature between right and wrong.) has remarked, is all
the less surprising, as man has emerged from a state of barbarism within a
comparatively recent period.  After having yielded to some temptation we
feel a sense of dissatisfaction, shame, repentance, or remorse, analogous
to the feelings caused by other powerful instincts or desires, when left
unsatisfied or baulked.  We compare the weakened impression of a past
temptation with the ever present social instincts, or with habits, gained
in early youth and strengthened during our whole lives, until they have
become almost as strong as instincts.  If with the temptation still before
us we do not yield, it is because either the social instinct or some custom
is at the moment predominant, or because we have learnt that it will appear
to us hereafter the stronger, when compared with the weakened impression of
the temptation, and we realise that its violation would cause us suffering.
Looking to future generations, there is no cause to fear that the social
instincts will grow weaker, and we may expect that virtuous habits will
grow stronger, becoming perhaps fixed by inheritance.  In this case the
struggle between our higher and lower impulses will be less severe, and
virtue will be triumphant.

SUMMARY OF THE LAST TWO CHAPTERS.

There can be no doubt that the difference between the mind of the lowest
man and that of the highest animal is immense.  An anthropomorphous ape, if
he could take a dispassionate view of his own case, would admit that though
he could form an artful plan to plunder a garden--though he could use
stones for fighting or for breaking open nuts, yet that the thought of
fashioning a stone into a tool was quite beyond his scope.  Still less, as
he would admit, could he follow out a train of metaphysical reasoning, or
solve a mathematical problem, or reflect on God, or admire a grand natural
scene.  Some apes, however, would probably declare that they could and did
admire the beauty of the coloured skin and fur of their partners in
marriage.  They would admit, that though they could make other apes
understand by cries some of their perceptions and simpler wants, the notion
of expressing definite ideas by definite sounds had never crossed their
minds.  They might insist that they were ready to aid their fellow-apes of
the same troop in many ways, to risk their lives for them, and to take
charge of their orphans; but they would be forced to acknowledge that
disinterested love for all living creatures, the most noble attribute of
man, was quite beyond their comprehension.

Nevertheless the difference in mind between man and the higher animals,
great as it is, certainly is one of degree and not of kind.  We have seen
that the senses and intuitions, the various emotions and faculties, such as
love, memory, attention, curiosity, imitation, reason, etc., of which man
boasts, may be found in an incipient, or even sometimes in a well-developed
condition, in the lower animals.  They are also capable of some inherited
improvement, as we see in the domestic dog compared with the wolf or
jackal.  If it could be proved that certain high mental powers, such as the
formation of general concepts, self-consciousness, etc., were absolutely
peculiar to man, which seems extremely doubtful, it is not improbable that
these qualities are merely the incidental results of other highly-advanced
intellectual faculties; and these again mainly the result of the continued
use of a perfect language.  At what age does the new-born infant possess
the power of abstraction, or become self-conscious, and reflect on its own
existence?  We cannot answer; nor can we answer in regard to the ascending
organic scale.  The half-art, half-instinct of language still bears the
stamp of its gradual evolution.  The ennobling belief in God is not
universal with man; and the belief in spiritual agencies naturally follows
from other mental powers.  The moral sense perhaps affords the best and
highest distinction between man and the lower animals; but I need say
nothing on this head, as I have so lately endeavoured to shew that the
social instincts,--the prime principle of man's moral constitution (50.
'The Thoughts of Marcus Aurelius,' etc., p. 139.)--with the aid of active
intellectual powers and the effects of habit, naturally lead to the golden
rule, "As ye would that men should do to you, do ye to them likewise;" and
this lies at the foundation of morality.

In the next chapter I shall make some few remarks on the probable steps and
means by which the several mental and moral faculties of man have been
gradually evolved.  That such evolution is at least possible, ought not to
be denied, for we daily see these faculties developing in every infant; and
we may trace a perfect gradation from the mind of an utter idiot, lower
than that of an animal low in the scale, to the mind of a Newton.


CHAPTER V.

ON THE DEVELOPMENT OF THE INTELLECTUAL AND MORAL FACULTIES DURING PRIMEVAL
AND CIVILISED TIMES.

Advancement of the intellectual powers through natural selection--
Importance of imitation--Social and moral faculties--Their development
within the limits of the same tribe--Natural selection as affecting
civilised nations--Evidence that civilised nations were once barbarous.

The subjects to be discussed in this chapter are of the highest interest,
but are treated by me in an imperfect and fragmentary manner.  Mr. Wallace,
in an admirable paper before referred to (1.  Anthropological Review, May
1864, p. clviii.), argues that man, after he had partially acquired those
intellectual and moral faculties which distinguish him from the lower
animals, would have been but little liable to bodily modifications through
natural selection or any other means.  For man is enabled through his
mental faculties "to keep with an unchanged body in harmony with the
changing universe."  He has great power of adapting his habits to new
conditions of life.  He invents weapons, tools, and various stratagems to
procure food and to defend himself.  When he migrates into a colder climate
he uses clothes, builds sheds, and makes fires; and by the aid of fire
cooks food otherwise indigestible.  He aids his fellow-men in many ways,
and anticipates future events.  Even at a remote period he practised some
division of labour.

The lower animals, on the other hand, must have their bodily structure
modified in order to survive under greatly changed conditions.  They must
be rendered stronger, or acquire more effective teeth or claws, for defence
against new enemies; or they must be reduced in size, so as to escape
detection and danger.  When they migrate into a colder climate, they must
become clothed with thicker fur, or have their constitutions altered.  If
they fail to be thus modified, they will cease to exist.

The case, however, is widely different, as Mr. Wallace has with justice
insisted, in relation to the intellectual and moral faculties of man.
These faculties are variable; and we have every reason to believe that the
variations tend to be inherited.  Therefore, if they were formerly of high
importance to primeval man and to his ape-like progenitors, they would have
been perfected or advanced through natural selection.  Of the high
importance of the intellectual faculties there can be no doubt, for man
mainly owes to them his predominant position in the world.  We can see,
that in the rudest state of society, the individuals who were the most
sagacious, who invented and used the best weapons or traps, and who were
best able to defend themselves, would rear the greatest number of
offspring.  The tribes, which included the largest number of men thus
endowed, would increase in number and supplant other tribes.  Numbers
depend primarily on the means of subsistence, and this depends partly on
the physical nature of the country, but in a much higher degree on the arts
which are there practised.  As a tribe increases and is victorious, it is
often still further increased by the absorption of other tribes.  (2.
After a time the members or tribes which are absorbed into another tribe
assume, as Sir Henry Maine remarks ('Ancient Law,' 1861, p. 131), that they
are the co-descendants of the same ancestors.)  The stature and strength of
the men of a tribe are likewise of some importance for its success, and
these depend in part on the nature and amount of the food which can be
obtained.  In Europe the men of the Bronze period were supplanted by a race
more powerful, and, judging from their sword-handles, with larger hands (3.
Morlot, 'Soc. Vaud. Sc. Nat.' 1860, p. 294.); but their success was
probably still more due to their superiority in the arts.

All that we know about savages, or may infer from their traditions and from
old monuments, the history of which is quite forgotten by the present
inhabitants, shew that from the remotest times successful tribes have
supplanted other tribes.  Relics of extinct or forgotten tribes have been
discovered throughout the civilised regions of the earth, on the wild
plains of America, and on the isolated islands in the Pacific Ocean.  At
the present day civilised nations are everywhere supplanting barbarous
nations, excepting where the climate opposes a deadly barrier; and they
succeed mainly, though not exclusively, through their arts, which are the
products of the intellect.  It is, therefore, highly probable that with
mankind the intellectual faculties have been mainly and gradually perfected
through natural selection; and this conclusion is sufficient for our
purpose.  Undoubtedly it would be interesting to trace the development of
each separate faculty from the state in which it exists in the lower
animals to that in which it exists in man; but neither my ability nor
knowledge permits the attempt.

It deserves notice that, as soon as the progenitors of man became social
(and this probably occurred at a very early period), the principle of
imitation, and reason, and experience would have increased, and much
modified the intellectual powers in a way, of which we see only traces in
the lower animals.  Apes are much given to imitation, as are the lowest
savages; and the simple fact previously referred to, that after a time no
animal can be caught in the same place by the same sort of trap, shews that
animals learn by experience, and imitate the caution of others.  Now, if
some one man in a tribe, more sagacious than the others, invented a new
snare or weapon, or other means of attack or defence, the plainest self-
interest, without the assistance of much reasoning power, would prompt the
other members to imitate him; and all would thus profit.  The habitual
practice of each new art must likewise in some slight degree strengthen the
intellect.  If the new invention were an important one, the tribe would
increase in number, spread, and supplant other tribes.  In a tribe thus
rendered more numerous there would always be a rather greater chance of the
birth of other superior and inventive members.  If such men left children
to inherit their mental superiority, the chance of the birth of still more
ingenious members would be somewhat better, and in a very small tribe
decidedly better.  Even if they left no children, the tribe would still
include their blood-relations; and it has been ascertained by
agriculturists (4.  I have given instances in my Variation of Animals under
Domestication, vol. ii. p. 196.) that by preserving and breeding from the
family of an animal, which when slaughtered was found to be valuable, the
desired character has been obtained.

Turning now to the social and moral faculties.  In order that primeval men,
or the ape-like progenitors of man, should become social, they must have
acquired the same instinctive feelings, which impel other animals to live
in a body; and they no doubt exhibited the same general disposition.  They
would have felt uneasy when separated from their comrades, for whom they
would have felt some degree of love; they would have warned each other of
danger, and have given mutual aid in attack or defence.  All this implies
some degree of sympathy, fidelity, and courage.  Such social qualities, the
paramount importance of which to the lower animals is disputed by no one,
were no doubt acquired by the progenitors of man in a similar manner,
namely, through natural selection, aided by inherited habit.  When two
tribes of primeval man, living in the same country, came into competition,
if (other circumstances being equal) the one tribe included a great number
of courageous, sympathetic and faithful members, who were always ready to
warn each other of danger, to aid and defend each other, this tribe would
succeed better and conquer the other.  Let it be borne in mind how all-
important in the never-ceasing wars of savages, fidelity and courage must
be.  The advantage which disciplined soldiers have over undisciplined
hordes follows chiefly from the confidence which each man feels in his
comrades.  Obedience, as Mr. Bagehot has well shewn (5.  See a remarkable
series of articles on 'Physics and Politics,' in the 'Fortnightly Review,'
Nov. 1867; April 1, 1868; July 1, 1869, since separately published.), is of
the highest value, for any form of government is better than none.  Selfish
and contentious people will not cohere, and without coherence nothing can
be effected.  A tribe rich in the above qualities would spread and be
victorious over other tribes:  but in the course of time it would, judging
from all past history, be in its turn overcome by some other tribe still
more highly endowed.  Thus the social and moral qualities would tend slowly
to advance and be diffused throughout the world.

But it may be asked, how within the limits of the same tribe did a large
number of members first become endowed with these social and moral
qualities, and how was the standard of excellence raised?  It is extremely
doubtful whether the offspring of the more sympathetic and benevolent
parents, or of those who were the most faithful to their comrades, would be
reared in greater numbers than the children of selfish and treacherous
parents belonging to the same tribe.  He who was ready to sacrifice his
life, as many a savage has been, rather than betray his comrades, would
often leave no offspring to inherit his noble nature.  The bravest men, who
were always willing to come to the front in war, and who freely risked
their lives for others, would on an average perish in larger numbers than
other men.  Therefore, it hardly seems probable, that the number of men
gifted with such virtues, or that the standard of their excellence, could
be increased through natural selection, that is, by the survival of the
fittest; for we are not here speaking of one tribe being victorious over
another.

Although the circumstances, leading to an increase in the number of those
thus endowed within the same tribe, are too complex to be clearly followed
out, we can trace some of the probable steps.  In the first place, as the
reasoning powers and foresight of the members became improved, each man
would soon learn that if he aided his fellow-men, he would commonly receive
aid in return.  From this low motive he might acquire the habit of aiding
his fellows; and the habit of performing benevolent actions certainly
strengthens the feeling of sympathy which gives the first impulse to
benevolent actions.  Habits, moreover, followed during many generations
probably tend to be inherited.

But another and much more powerful stimulus to the development of the
social virtues, is afforded by the praise and the blame of our fellow-men.
To the instinct of sympathy, as we have already seen, it is primarily due,
that we habitually bestow both praise and blame on others, whilst we love
the former and dread the latter when applied to ourselves; and this
instinct no doubt was originally acquired, like all the other social
instincts, through natural selection.  At how early a period the
progenitors of man in the course of their development, became capable of
feeling and being impelled by, the praise or blame of their fellow-
creatures, we cannot of course say.  But it appears that even dogs
appreciate encouragement, praise, and blame.  The rudest savages feel the
sentiment of glory, as they clearly shew by preserving the trophies of
their prowess, by their habit of excessive boasting, and even by the
extreme care which they take of their personal appearance and decorations;
for unless they regarded the opinion of their comrades, such habits would
be senseless.

They certainly feel shame at the breach of some of their lesser rules, and
apparently remorse, as shewn by the case of the Australian who grew thin
and could not rest from having delayed to murder some other woman, so as to
propitiate his dead wife's spirit.  Though I have not met with any other
recorded case, it is scarcely credible that a savage, who will sacrifice
his life rather than betray his tribe, or one who will deliver himself up
as a prisoner rather than break his parole (6.  Mr. Wallace gives cases in
his 'Contributions to the Theory of Natural Selection,' 1870, p. 354.),
would not feel remorse in his inmost soul, if he had failed in a duty,
which he held sacred.

We may therefore conclude that primeval man, at a very remote period, was
influenced by the praise and blame of his fellows.  It is obvious, that the
members of the same tribe would approve of conduct which appeared to them
to be for the general good, and would reprobate that which appeared evil.
To do good unto others--to do unto others as ye would they should do unto
you--is the foundation-stone of morality.  It is, therefore, hardly
possible to exaggerate the importance during rude times of the love of
praise and the dread of blame.  A man who was not impelled by any deep,
instinctive feeling, to sacrifice his life for the good of others, yet was
roused to such actions by a sense of glory, would by his example excite the
same wish for glory in other men, and would strengthen by exercise the
noble feeling of admiration.  He might thus do far more good to his tribe
than by begetting offspring with a tendency to inherit his own high
character.

With increased experience and reason, man perceives the more remote
consequences of his actions, and the self-regarding virtues, such as
temperance, chastity, etc., which during early times are, as we have before
seen, utterly disregarded, come to be highly esteemed or even held sacred.
I need not, however, repeat what I have said on this head in the fourth
chapter.  Ultimately our moral sense or conscience becomes a highly complex
sentiment--originating in the social instincts, largely guided by the
approbation of our fellow-men, ruled by reason, self-interest, and in later
times by deep religious feelings, and confirmed by instruction and habit.

It must not be forgotten that although a high standard of morality gives
but a slight or no advantage to each individual man and his children over
the other men of the same tribe, yet that an increase in the number of
well-endowed men and an advancement in the standard of morality will
certainly give an immense advantage to one tribe over another.  A tribe
including many members who, from possessing in a high degree the spirit of
patriotism, fidelity, obedience, courage, and sympathy, were always ready
to aid one another, and to sacrifice themselves for the common good, would
be victorious over most other tribes; and this would be natural selection.
At all times throughout the world tribes have supplanted other tribes; and
as morality is one important element in their success, the standard of
morality and the number of well-endowed men will thus everywhere tend to
rise and increase.

It is, however, very difficult to form any judgment why one particular
tribe and not another has been successful and has risen in the scale of
civilisation.  Many savages are in the same condition as when first
discovered several centuries ago.  As Mr. Bagehot has remarked, we are apt
to look at progress as normal in human society; but history refutes this.
The ancients did not even entertain the idea, nor do the Oriental nations
at the present day.  According to another high authority, Sir Henry Maine
(7.  'Ancient Law,' 1861, p. 22.  For Mr. Bagehot's remarks, 'Fortnightly
Review,' April 1, 1868, p. 452.), "the greatest part of mankind has never
shewn a particle of desire that its civil institutions should be improved."
Progress seems to depend on many concurrent favourable conditions, far too
complex to be followed out.  But it has often been remarked, that a cool
climate, from leading to industry and to the various arts, has been highly
favourable thereto.  The Esquimaux, pressed by hard necessity, have
succeeded in many ingenious inventions, but their climate has been too
severe for continued progress.  Nomadic habits, whether over wide plains,
or through the dense forests of the tropics, or along the shores of the
sea, have in every case been highly detrimental.  Whilst observing the
barbarous inhabitants of Tierra del Fuego, it struck me that the possession
of some property, a fixed abode, and the union of many families under a
chief, were the indispensable requisites for civilisation.  Such habits
almost necessitate the cultivation of the ground; and the first steps in
cultivation would probably result, as I have elsewhere shewn (8.  'The
Variation of Animals and Plants under Domestication,' vol. i. p. 309.),
from some such accident as the seeds of a fruit-tree falling on a heap of
refuse, and producing an unusually fine variety.  The problem, however, of
the first advance of savages towards civilisation is at present much too
difficult to be solved.

NATURAL SELECTION AS AFFECTING CIVILISED NATIONS.

I have hitherto only considered the advancement of man from a semi-human
condition to that of the modern savage.  But some remarks on the action of
natural selection on civilised nations may be worth adding.  This subject
has been ably discussed by Mr. W.R. Greg (9.  'Fraser's Magazine,' Sept.
1868, p. 353.  This article seems to have struck many persons, and has
given rise to two remarkable essays and a rejoinder in the 'Spectator,'
Oct. 3rd and 17th, 1868.  It has also been discussed in the 'Quarterly
Journal of Science,' 1869, p. 152, and by Mr. Lawson Tait in the 'Dublin
Quarterly Journal of Medical Science,' Feb. 1869, and by Mr. E. Ray
Lankester in his 'Comparative Longevity,' 1870, p. 128.  Similar views
appeared previously in the 'Australasian,' July 13, 1867.  I have borrowed
ideas from several of these writers.), and previously by Mr. Wallace and
Mr. Galton.  (10.  For Mr. Wallace, see 'Anthropological Review,' as before
cited.  Mr. Galton in 'Macmillan's Magazine,' Aug. 1865, p. 318; also his
great work, 'Hereditary Genius,' 1870.)  Most of my remarks are taken from
these three authors.  With savages, the weak in body or mind are soon
eliminated; and those that survive commonly exhibit a vigorous state of
health.  We civilised men, on the other hand, do our utmost to check the
process of elimination; we build asylums for the imbecile, the maimed, and
the sick; we institute poor-laws; and our medical men exert their utmost
skill to save the life of every one to the last moment.  There is reason to
believe that vaccination has preserved thousands, who from a weak
constitution would formerly have succumbed to small-pox.  Thus the weak
members of civilised societies propagate their kind.  No one who has
attended to the breeding of domestic animals will doubt that this must be
highly injurious to the race of man.  It is surprising how soon a want of
care, or care wrongly directed, leads to the degeneration of a domestic
race; but excepting in the case of man himself, hardly any one is so
ignorant as to allow his worst animals to breed.

The aid which we feel impelled to give to the helpless is mainly an
incidental result of the instinct of sympathy, which was originally
acquired as part of the social instincts, but subsequently rendered, in the
manner previously indicated, more tender and more widely diffused.  Nor
could we check our sympathy, even at the urging of hard reason, without
deterioration in the noblest part of our nature.  The surgeon may harden
himself whilst performing an operation, for he knows that he is acting for
the good of his patient; but if we were intentionally to neglect the weak
and helpless, it could only be for a contingent benefit, with an
overwhelming present evil.  We must therefore bear the undoubtedly bad
effects of the weak surviving and propagating their kind; but there appears
to be at least one check in steady action, namely that the weaker and
inferior members of society do not marry so freely as the sound; and this
check might be indefinitely increased by the weak in body or mind
refraining from marriage, though this is more to be hoped for than
expected.

In every country in which a large standing army is kept up, the finest
young men are taken by the conscription or are enlisted.  They are thus
exposed to early death during war, are often tempted into vice, and are
prevented from marrying during the prime of life.  On the other hand the
shorter and feebler men, with poor constitutions, are left at home, and
consequently have a much better chance of marrying and propagating their
kind.  (11. Prof. H. Fick ('Einfluss der Naturwissenschaft auf das Recht,'
June 1872) has some good remarks on this head, and on other such points.)

Man accumulates property and bequeaths it to his children, so that the
children of the rich have an advantage over the poor in the race for
success, independently of bodily or mental superiority.  On the other hand,
the children of parents who are short-lived, and are therefore on an
average deficient in health and vigour, come into their property sooner
than other children, and will be likely to marry earlier, and leave a
larger number of offspring to inherit their inferior constitutions.  But
the inheritance of property by itself is very far from an evil; for without
the accumulation of capital the arts could not progress; and it is chiefly
through their power that the civilised races have extended, and are now
everywhere extending their range, so as to take the place of the lower
races.  Nor does the moderate accumulation of wealth interfere with the
process of selection.  When a poor man becomes moderately rich, his
children enter trades or professions in which there is struggle enough, so
that the able in body and mind succeed best.  The presence of a body of
well-instructed men, who have not to labour for their daily bread, is
important to a degree which cannot be over-estimated; as all high
intellectual work is carried on by them, and on such work, material
progress of all kinds mainly depends, not to mention other and higher
advantages.  No doubt wealth when very great tends to convert men into
useless drones, but their number is never large; and some degree of
elimination here occurs, for we daily see rich men, who happen to be fools
or profligate, squandering away their wealth.

Primogeniture with entailed estates is a more direct evil, though it may
formerly have been a great advantage by the creation of a dominant class,
and any government is better than none.  Most eldest sons, though they may
be weak in body or mind, marry, whilst the younger sons, however superior
in these respects, do not so generally marry.  Nor can worthless eldest
sons with entailed estates squander their wealth.  But here, as elsewhere,
the relations of civilised life are so complex that some compensatory
checks intervene.  The men who are rich through primogeniture are able to
select generation after generation the more beautiful and charming women;
and these must generally be healthy in body and active in mind.  The evil
consequences, such as they may be, of the continued preservation of the
same line of descent, without any selection, are checked by men of rank
always wishing to increase their wealth and power; and this they effect by
marrying heiresses.  But the daughters of parents who have produced single
children, are themselves, as Mr. Galton (12. 'Hereditary Genius,' 1870, pp.
132-140.) has shewn, apt to be sterile; and thus noble families are
continually cut off in the direct line, and their wealth flows into some
side channel; but unfortunately this channel is not determined by
superiority of any kind.

Although civilisation thus checks in many ways the action of natural
selection, it apparently favours the better development of the body, by
means of good food and the freedom from occasional hardships.  This may be
inferred from civilised men having been found, wherever compared, to be
physically stronger than savages.  (13. Quatrefages, 'Revue des Cours
Scientifiques,' 1867-68, p. 659.)  They appear also to have equal powers of
endurance, as has been proved in many adventurous expeditions.  Even the
great luxury of the rich can be but little detrimental; for the expectation
of life of our aristocracy, at all ages and of both sexes, is very little
inferior to that of healthy English lives in the lower classes.   (14.
See the fifth and sixth columns, compiled from good authorities, in the
table given in Mr. E.R. Lankester's 'Comparative Longevity,' 1870, p. 115.)

We will now look to the intellectual faculties.  If in each grade of
society the members were divided into two equal bodies, the one including
the intellectually superior and the other the inferior, there can be little
doubt that the former would succeed best in all occupations, and rear a
greater number of children.  Even in the lowest walks of life, skill and
ability must be of some advantage; though in many occupations, owing to the
great division of labour, a very small one.  Hence in civilised nations
there will be some tendency to an increase both in the number and in the
standard of the intellectually able.  But I do not wish to assert that this
tendency may not be more than counterbalanced in other ways, as by the
multiplication of the reckless and improvident; but even to such as these,
ability must be some advantage.

It has often been objected to views like the foregoing, that the most
eminent men who have ever lived have left no offspring to inherit their
great intellect.  Mr. Galton says, "I regret I am unable to solve the
simple question whether, and how far, men and women who are prodigies of
genius are infertile.  I have, however, shewn that men of eminence are by
no means so."  (15.  'Hereditary Genius,' 1870, p. 330.)  Great lawgivers,
the founders of beneficent religions, great philosophers and discoverers in
science, aid the progress of mankind in a far higher degree by their works
than by leaving a numerous progeny.  In the case of corporeal structures,
it is the selection of the slightly better-endowed and the elimination of
the slightly less well-endowed individuals, and not the preservation of
strongly-marked and rare anomalies, that leads to the advancement of a
species.  (16.  'Origin of Species' (fifth edition, 1869), p. 104.)  So it
will be with the intellectual faculties, since the somewhat abler men in
each grade of society succeed rather better than the less able, and
consequently increase in number, if not otherwise prevented.  When in any
nation the standard of intellect and the number of intellectual men have
increased, we may expect from the law of the deviation from an average,
that prodigies of genius will, as shewn by Mr. Galton, appear somewhat more
frequently than before.

In regard to the moral qualities, some elimination of the worst
dispositions is always in progress even in the most civilised nations.
Malefactors are executed, or imprisoned for long periods, so that they
cannot freely transmit their bad qualities.  Melancholic and insane persons
are confined, or commit suicide.  Violent and quarrelsome men often come to
a bloody end.  The restless who will not follow any steady occupation--and
this relic of barbarism is a great check to civilisation (17.  'Hereditary
Genius,' 1870, p. 347.)--emigrate to newly-settled countries; where they
prove useful pioneers.  Intemperance is so highly destructive, that the
expectation of life of the intemperate, at the age of thirty for instance,
is only 13.8 years; whilst for the rural labourers of England at the same
age it is 40.59 years.  (18.  E. Ray Lankester, 'Comparative Longevity,'
1870, p. 115.  The table of the intemperate is from Neison's 'Vital
Statistics.'  In regard to profligacy, see Dr. Farr, 'Influence of Marriage
on Mortality,' 'Nat. Assoc. for the Promotion of Social Science,' 1858.)
Profligate women bear few children, and profligate men rarely marry; both
suffer from disease.  In the breeding of domestic animals, the elimination
of those individuals, though few in number, which are in any marked manner
inferior, is by no means an unimportant element towards success.  This
especially holds good with injurious characters which tend to reappear
through reversion, such as blackness in sheep; and with mankind some of the
worst dispositions, which occasionally without any assignable cause make
their appearance in families, may perhaps be reversions to a savage state,
from which we are not removed by very many generations.  This view seems
indeed recognised in the common expression that such men are the black
sheep of the family.

With civilised nations, as far as an advanced standard of morality, and an
increased number of fairly good men are concerned, natural selection
apparently effects but little; though the fundamental social instincts were
originally thus gained.  But I have already said enough, whilst treating of
the lower races, on the causes which lead to the advance of morality,
namely, the approbation of our fellow-men--the strengthening of our
sympathies by habit--example and imitation--reason--experience, and even
self-interest--instruction during youth, and religious feelings.

A most important obstacle in civilised countries to an increase in the
number of men of a superior class has been strongly insisted on by Mr. Greg
and Mr. Galton (19.  'Fraser's Magazine,' Sept. 1868, p. 353.  'Macmillan's
Magazine,' Aug. 1865, p. 318.  The Rev. F.W. Farrar ('Fraser's Magazine,'
Aug. 1870, p. 264) takes a different view.), namely, the fact that the very
poor and reckless, who are often degraded by vice, almost invariably marry
early, whilst the careful and frugal, who are generally otherwise virtuous,
marry late in life, so that they may be able to support themselves and
their children in comfort.  Those who marry early produce within a given
period not only a greater number of generations, but, as shewn by Dr.
Duncan (20.  'On the Laws of the Fertility of Women,' in 'Transactions of
the Royal Society,' Edinburgh, vol. xxiv. p. 287; now published separately
under the title of 'Fecundity, Fertility, and Sterility,' 1871.  See, also,
Mr. Galton, 'Hereditary Genius,' pp. 352-357, for observations to the above
effect.), they produce many more children.  The children, moreover, that
are borne by mothers during the prime of life are heavier and larger, and
therefore probably more vigorous, than those born at other periods.  Thus
the reckless, degraded, and often vicious members of society, tend to
increase at a quicker rate than the provident and generally virtuous
members.  Or as Mr. Greg puts the case:  "The careless, squalid, unaspiring
Irishman multiplies like rabbits:  the frugal, foreseeing, self-respecting,
ambitious Scot, stern in his morality, spiritual in his faith, sagacious
and disciplined in his intelligence, passes his best years in struggle and
in celibacy, marries late, and leaves few behind him.  Given a land
originally peopled by a thousand Saxons and a thousand Celts--and in a
dozen generations five-sixths of the population would be Celts, but five-
sixths of the property, of the power, of the intellect, would belong to the
one-sixth of Saxons that remained.  In the eternal 'struggle for
existence,' it would be the inferior and LESS favoured race that had
prevailed--and prevailed by virtue not of its good qualities but of its
faults."

There are, however, some checks to this downward tendency.  We have seen
that the intemperate suffer from a high rate of mortality, and the
extremely profligate leave few offspring.  The poorest classes crowd into
towns, and it has been proved by Dr. Stark from the statistics of ten years
in Scotland (21.  'Tenth Annual Report of Births, Deaths, etc., in
Scotland,' 1867, p. xxix.), that at all ages the death-rate is higher in
towns than in rural districts, "and during the first five years of life the
town death-rate is almost exactly double that of the rural districts."  As
these returns include both the rich and the poor, no doubt more than twice
the number of births would be requisite to keep up the number of the very
poor inhabitants in the towns, relatively to those in the country.  With
women, marriage at too early an age is highly injurious; for it has been
found in France that, "Twice as many wives under twenty die in the year, as
died out of the same number of the unmarried."  The mortality, also, of
husbands under twenty is "excessively high" (22.  These quotations are
taken from our highest authority on such questions, namely, Dr. Farr, in
his paper 'On the Influence of Marriage on the Mortality of the French
People,' read before the Nat. Assoc. for the Promotion of Social Science,
1858.), but what the cause of this may be, seems doubtful.  Lastly, if the
men who prudently delay marrying until they can bring up their families in
comfort, were to select, as they often do, women in the prime of life, the
rate of increase in the better class would be only slightly lessened.

It was established from an enormous body of statistics, taken during 1853,
that the unmarried men throughout France, between the ages of twenty and
eighty, die in a much larger proportion than the married:  for instance,
out of every 1000 unmarried men, between the ages of twenty and thirty,
11.3 annually died, whilst of the married, only 6.5 died.  (23.  Dr. Farr,
ibid.  The quotations given below are extracted from the same striking
paper.)  A similar law was proved to hold good, during the years 1863 and
1864, with the entire population above the age of twenty in Scotland:  for
instance, out of every 1000 unmarried men, between the ages of twenty and
thirty, 14.97 annually died, whilst of the married only 7.24 died, that is
less than half.  (24. I have taken the mean of the quinquennial means,
given in 'The Tenth Annual Report of Births, Deaths, etc., in Scotland,'
1867.  The quotation from Dr. Stark is copied from an article in the 'Daily
News,' Oct. 17, 1868, which Dr. Farr considers very carefully written.)
Dr. Stark remarks on this, "Bachelorhood is more destructive to life than
the most unwholesome trades, or than residence in an unwholesome house or
district where there has never been the most distant attempt at sanitary
improvement."  He considers that the lessened mortality is the direct
result of "marriage, and the more regular domestic habits which attend that
state."  He admits, however, that the intemperate, profligate, and criminal
classes, whose duration of life is low, do not commonly marry; and it must
likewise be admitted that men with a weak constitution, ill health, or any
great infirmity in body or mind, will often not wish to marry, or will be
rejected.  Dr. Stark seems to have come to the conclusion that marriage in
itself is a main cause of prolonged life, from finding that aged married
men still have a considerable advantage in this respect over the unmarried
of the same advanced age; but every one must have known instances of men,
who with weak health during youth did not marry, and yet have survived to
old age, though remaining weak, and therefore always with a lessened chance
of life or of marrying.  There is another remarkable circumstance which
seems to support Dr. Stark's conclusion, namely, that widows and widowers
in France suffer in comparison with the married a very heavy rate of
mortality; but Dr. Farr attributes this to the poverty and evil habits
consequent on the disruption of the family, and to grief.  On the whole we
may conclude with Dr. Farr that the lesser mortality of married than of
unmarried men, which seems to be a general law, "is mainly due to the
constant elimination of imperfect types, and to the skilful selection of
the finest individuals out of each successive generation;" the selection
relating only to the marriage state, and acting on all corporeal,
intellectual, and moral qualities.  (25.  Dr. Duncan remarks ('Fecundity,
Fertility, etc.' 1871, p. 334) on this subject:  "At every age the healthy
and beautiful go over from the unmarried side to the married, leaving the
unmarried columns crowded with the sickly and unfortunate.")  We may,
therefore, infer that sound and good men who out of prudence remain for a
time unmarried, do not suffer a high rate of mortality.

If the various checks specified in the two last paragraphs, and perhaps
others as yet unknown, do not prevent the reckless, the vicious and
otherwise inferior members of society from increasing at a quicker rate
than the better class of men, the nation will retrograde, as has too often
occurred in the history of the world.  We must remember that progress is no
invariable rule.  It is very difficult to say why one civilised nation
rises, becomes more powerful, and spreads more widely, than another; or why
the same nation progresses more quickly at one time than at another.  We
can only say that it depends on an increase in the actual number of the
population, on the number of men endowed with high intellectual and moral
faculties, as well as on their standard of excellence.  Corporeal structure
appears to have little influence, except so far as vigour of body leads to
vigour of mind.

It has been urged by several writers that as high intellectual powers are
advantageous to a nation, the old Greeks, who stood some grades higher in
intellect than any race that has ever existed (26.  See the ingenious and
original argument on this subject by Mr. Galton, 'Hereditary Genius,' pp.
340-342.), ought, if the power of natural selection were real, to have
risen still higher in the scale, increased in number, and stocked the whole
of Europe.  Here we have the tacit assumption, so often made with respect
to corporeal structures, that there is some innate tendency towards
continued development in mind and body.  But development of all kinds
depends on many concurrent favourable circumstances.  Natural selection
acts only tentatively.  Individuals and races may have acquired certain
indisputable advantages, and yet have perished from failing in other
characters.  The Greeks may have retrograded from a want of coherence
between the many small states, from the small size of their whole country,
from the practice of slavery, or from extreme sensuality; for they did not
succumb until "they were enervated and corrupt to the very core."  (27.
Mr. Greg, 'Fraser's Magazine,' Sept. 1868, p. 357.)  The western nations of
Europe, who now so immeasurably surpass their former savage progenitors,
and stand at the summit of civilisation, owe little or none of their
superiority to direct inheritance from the old Greeks, though they owe much
to the written works of that wonderful people.

Who can positively say why the Spanish nation, so dominant at one time, has
been distanced in the race.  The awakening of the nations of Europe from
the dark ages is a still more perplexing problem.  At that early period, as
Mr. Galton has remarked, almost all the men of a gentle nature, those given
to meditation or culture of the mind, had no refuge except in the bosom of
a Church which demanded celibacy (28.  'Hereditary Genius,' 1870, pp. 357-
359.  The Rev. F.W. Farrar ('Fraser's Magazine,' Aug. 1870, p. 257)
advances arguments on the other side.  Sir C. Lyell had already
('Principles of Geology,' vol. ii. 1868, p. 489), in a striking passage
called attention to the evil influence of the Holy Inquisition in having,
through selection, lowered the general standard of intelligence in
Europe.); and this could hardly fail to have had a deteriorating influence
on each successive generation.  During this same period the Holy
Inquisition selected with extreme care the freest and boldest men in order
to burn or imprison them.  In Spain alone some of the best men--those who
doubted and questioned, and without doubting there can be no progress--were
eliminated during three centuries at the rate of a thousand a year.  The
evil which the Catholic Church has thus effected is incalculable, though no
doubt counterbalanced to a certain, perhaps to a large, extent in other
ways; nevertheless, Europe has progressed at an unparalleled rate.

The remarkable success of the English as colonists, compared to other
European nations, has been ascribed to their "daring and persistent
energy"; a result which is well illustrated by comparing the progress of
the Canadians of English and French extraction; but who can say how the
English gained their energy?  There is apparently much truth in the belief
that the wonderful progress of the United States, as well as the character
of the people, are the results of natural selection; for the more
energetic, restless, and courageous men from all parts of Europe have
emigrated during the last ten or twelve generations to that great country,
and have there succeeded best.  (29.  Mr. Galton, 'Macmillan's Magazine,'
August 1865, p. 325.  See also, 'Nature,' 'On Darwinism and National Life,'
Dec. 1869, p. 184.)  Looking to the distant future, I do not think that the
Rev. Mr. Zincke takes an exaggerated view when he says (30.  'Last Winter
in the United States,' 1868, p. 29.):  "All other series of events--as that
which resulted in the culture of mind in Greece, and that which resulted in
the empire of Rome--only appear to have purpose and value when viewed in
connection with, or rather as subsidiary to...the great stream of Anglo-
Saxon emigration to the west."  Obscure as is the problem of the advance of
civilisation, we can at least see that a nation which produced during a
lengthened period the greatest number of highly intellectual, energetic,
brave, patriotic, and benevolent men, would generally prevail over less
favoured nations.

Natural selection follows from the struggle for existence; and this from a
rapid rate of increase.  It is impossible not to regret bitterly, but
whether wisely is another question, the rate at which man tends to
increase; for this leads in barbarous tribes to infanticide and many other
evils, and in civilised nations to abject poverty, celibacy, and to the
late marriages of the prudent.  But as man suffers from the same physical
evils as the lower animals, he has no right to expect an immunity from the
evils consequent on the struggle for existence.  Had he not been subjected
during primeval times to natural selection, assuredly he would never have
attained to his present rank.  Since we see in many parts of the world
enormous areas of the most fertile land capable of supporting numerous
happy homes, but peopled only by a few wandering savages, it might be
argued that the struggle for existence had not been sufficiently severe to
force man upwards to his highest standard.  Judging from all that we know
of man and the lower animals, there has always been sufficient variability
in their intellectual and moral faculties, for a steady advance through
natural selection.  No doubt such advance demands many favourable
concurrent circumstances; but it may well be doubted whether the most
favourable would have sufficed, had not the rate of increase been rapid,
and the consequent struggle for existence extremely severe.  It even
appears from what we see, for instance, in parts of S. America, that a
people which may be called civilised, such as the Spanish settlers, is
liable to become indolent and to retrograde, when the conditions of life
are very easy.  With highly civilised nations continued progress depends in
a subordinate degree on natural selection; for such nations do not supplant
and exterminate one another as do savage tribes.  Nevertheless the more
intelligent members within the same community will succeed better in the
long run than the inferior, and leave a more numerous progeny, and this is
a form of natural selection.  The more efficient causes of progress seem to
consist of a good education during youth whilst the brain is impressible,
and of a high standard of excellence, inculcated by the ablest and best
men, embodied in the laws, customs and traditions of the nation, and
enforced by public opinion.  It should, however, be borne in mind, that the
enforcement of public opinion depends on our appreciation of the
approbation and disapprobation of others; and this appreciation is founded
on our sympathy, which it can hardly be doubted was originally developed
through natural selection as one of the most important elements of the
social instincts.  (31.  I am much indebted to Mr. John Morley for some
good criticisms on this subject:  see, also Broca, 'Les Selections,' 'Revue
d'Anthropologie,' 1872.)

ON THE EVIDENCE THAT ALL CIVILISED NATIONS WERE ONCE BARBAROUS.

The present subject has been treated in so full and admirable a manner by
Sir J. Lubbock (32.  'On the Origin of Civilisation,' 'Proceedings of the
Ethnological Society,' Nov. 26, 1867.),  Mr. Tylor, Mr. M'Lennan, and
others, that I need here give only the briefest summary of their results.
The arguments recently advanced by the Duke of Argyll (33.  'Primeval Man,'
1869.) and formerly by Archbishop Whately, in favour of the belief that man
came into the world as a civilised being, and that all savages have since
undergone degradation, seem to me weak in comparison with those advanced on
the other side.  Many nations, no doubt, have fallen away in civilisation,
and some may have lapsed into utter barbarism, though on this latter head I
have met with no evidence.  The Fuegians were probably compelled by other
conquering hordes to settle in their inhospitable country, and they may
have become in consequence somewhat more degraded; but it would be
difficult to prove that they have fallen much below the Botocudos, who
inhabit the finest parts of Brazil.

The evidence that all civilised nations are the descendants of barbarians,
consists, on the one side, of clear traces of their former low condition in
still-existing customs, beliefs, language, etc.; and on the other side, of
proofs that savages are independently able to raise themselves a few steps
in the scale of civilisation, and have actually thus risen.  The evidence
on the first head is extremely curious, but cannot be here given:  I refer
to such cases as that of the art of enumeration, which, as Mr. Tylor
clearly shews by reference to the words still used in some places,
originated in counting the fingers, first of one hand and then of the
other, and lastly of the toes.  We have traces of this in our own decimal
system, and in the Roman numerals, where, after the V, which is supposed to
be an abbreviated picture of a human hand, we pass on to VI, etc., when the
other hand no doubt was used.  So again, "when we speak of three-score and
ten, we are counting by the vigesimal system, each score thus ideally made,
standing for 20--for 'one man' as a Mexican or Carib would put it."  (34.
'Royal Institution of Great Britain,' March 15, 1867.  Also, 'Researches
into the Early History of Mankind,' 1865.)  According to a large and
increasing school of philologists, every language bears the marks of its
slow and gradual evolution.  So it is with the art of writing, for letters
are rudiments of pictorial representations.  It is hardly possible to read
Mr. M'Lennan's work (35.  'Primitive Marriage,' 1865.  See, likewise, an
excellent article, evidently by the same author, in the 'North British
Review,' July 1869.  Also, Mr. L.H. Morgan, 'A Conjectural Solution of the
Origin of the Class. System of Relationship,' in 'Proc. American Acad. of
Sciences,' vol. vii. Feb. 1868.  Prof. Schaaffhausen ('Anthropolog.
Review,' Oct. 1869, p. 373) remarks on "the vestiges of human sacrifices
found both in Homer and the Old Testament.") and not admit that almost all
civilised nations still retain traces of such rude habits as the forcible
capture of wives.  What ancient nation, as the same author asks, can be
named that was originally monogamous?  The primitive idea of justice, as
shewn by the law of battle and other customs of which vestiges still
remain, was likewise most rude.  Many existing superstitions are the
remnants of former false religious beliefs.  The highest form of religion--
the grand idea of God hating sin and loving righteousness--was unknown
during primeval times.

Turning to the other kind of evidence:  Sir J. Lubbock has shewn that some
savages have recently improved a little in some of their simpler arts.
From the extremely curious account which he gives of the weapons, tools,
and arts, in use amongst savages in various parts of the world, it cannot
be doubted that these have nearly all been independent discoveries,
excepting perhaps the art of making fire.  (36.  Sir J. Lubbock,
'Prehistoric Times,' 2nd edit. 1869, chaps. xv. and xvi. et passim.  See
also the excellent 9th Chapter in Tylor's 'Early History of Mankind,' 2nd
edit., 1870.)  The Australian boomerang is a good instance of one such
independent discovery.  The Tahitians when first visited had advanced in
many respects beyond the inhabitants of most of the other Polynesian
islands.  There are no just grounds for the belief that the high culture of
the native Peruvians and Mexicans was derived from abroad (37.  Dr. F.
Mueller has made some good remarks to this effect in the 'Reise der Novara:
Anthropolog. Theil,' Abtheil. iii. 1868, s. 127.); many native plants were
there cultivated, and a few native animals domesticated.  We should bear in
mind that, judging from the small influence of most missionaries, a
wandering crew from some semi-civilised land, if washed to the shores of
America, would not have produced any marked effect on the natives, unless
they had already become somewhat advanced.  Looking to a very remote period
in the history of the world, we find, to use Sir J. Lubbock's well-known
terms, a paleolithic and neolithic period; and no one will pretend that the
art of grinding rough flint tools was a borrowed one.  In all parts of
Europe, as far east as Greece, in Palestine, India, Japan, New Zealand, and
Africa, including Egypt, flint tools have been discovered in abundance; and
of their use the existing inhabitants retain no tradition.  There is also
indirect evidence of their former use by the Chinese and ancient Jews.
Hence there can hardly be a doubt that the inhabitants of these countries,
which include nearly the whole civilised world, were once in a barbarous
condition.  To believe that man was aboriginally civilised and then
suffered utter degradation in so many regions, is to take a pitiably low
view of human nature.  It is apparently a truer and more cheerful view that
progress has been much more general than retrogression; that man has risen,
though by slow and interrupted steps, from a lowly condition to the highest
standard as yet attained by him in knowledge, morals and religion.


CHAPTER VI.

ON THE AFFINITIES AND GENEALOGY OF MAN.

Position of man in the animal series--The natural system genealogical--
Adaptive characters of slight value--Various small points of resemblance
between man and the Quadrumana--Rank of man in the natural system--
Birthplace and antiquity of man--Absence of fossil connecting links--Lower
stages in the genealogy of man, as inferred, firstly from his affinities
and secondly from his structure--Early androgynous condition of the
Vertebrata--Conclusion.

Even if it be granted that the difference between man and his nearest
allies is as great in corporeal structure as some naturalists maintain, and
although we must grant that the difference between them is immense in
mental power, yet the facts given in the earlier chapters appear to
declare, in the plainest manner, that man is descended from some lower
form, notwithstanding that connecting-links have not hitherto been
discovered.

Man is liable to numerous, slight, and diversified variations, which are
induced by the same general causes, are governed and transmitted in
accordance with the same general laws, as in the lower animals.  Man has
multiplied so rapidly, that he has necessarily been exposed to struggle for
existence, and consequently to natural selection.  He has given rise to
many races, some of which differ so much from each other, that they have
often been ranked by naturalists as distinct species.  His body is
constructed on the same homological plan as that of other mammals.  He
passes through the same phases of embryological development.  He retains
many rudimentary and useless structures, which no doubt were once
serviceable.  Characters occasionally make their re-appearance in him,
which we have reason to believe were possessed by his early progenitors.
If the origin of man had been wholly different from that of all other
animals, these various appearances would be mere empty deceptions; but such
an admission is incredible.  These appearances, on the other hand, are
intelligible, at least to a large extent, if man is the co-descendant with
other mammals of some unknown and lower form.

Some naturalists, from being deeply impressed with the mental and spiritual
powers of man, have divided the whole organic world into three kingdoms,
the Human, the Animal, and the Vegetable, thus giving to man a separate
kingdom.  (1.  Isidore Geoffroy St.-Hilaire gives a detailed account of the
position assigned to man by various naturalists in their classifications:
'Hist. Nat. Gen.' tom. ii. 1859, pp. 170-189.)  Spiritual powers cannot be
compared or classed by the naturalist:  but he may endeavour to shew, as I
have done, that the mental faculties of man and the lower animals do not
differ in kind, although immensely in degree.  A difference in degree,
however great, does not justify us in placing man in a distinct kingdom, as
will perhaps be best illustrated by comparing the mental powers of two
insects, namely, a coccus or scale-insect and an ant, which undoubtedly
belong to the same class.  The difference is here greater than, though of a
somewhat different kind from, that between man and the highest mammal.  The
female coccus, whilst young, attaches itself by its proboscis to a plant;
sucks the sap, but never moves again; is fertilised and lays eggs; and this
is its whole history.  On the other hand, to describe the habits and mental
powers of worker-ants, would require, as Pierre Huber has shewn, a large
volume; I may, however, briefly specify a few points.  Ants certainly
communicate information to each other, and several unite for the same work,
or for games of play.  They recognise their fellow-ants after months of
absence, and feel sympathy for each other.  They build great edifices, keep
them clean, close the doors in the evening, and post sentries.  They make
roads as well as tunnels under rivers, and temporary bridges over them, by
clinging together.  They collect food for the community, and when an
object, too large for entrance, is brought to the nest, they enlarge the
door, and afterwards build it up again.  They store up seeds, of which they
prevent the germination, and which, if damp, are brought up to the surface
to dry.  They keep aphides and other insects as milch-cows.  They go out to
battle in regular bands, and freely sacrifice their lives for the common
weal.  They emigrate according to a preconcerted plan.  They capture
slaves.  They move the eggs of their aphides, as well as their own eggs and
cocoons, into warm parts of the nest, in order that they may be quickly
hatched; and endless similar facts could be given.  (2.  Some of the most
interesting facts ever published on the habits of ants are given by Mr.
Belt, in his 'Naturalist in Nicaragua,' 1874.  See also Mr. Moggridge's
admirable work, 'Harvesting Ants,' etc., 1873, also 'L'Instinct chez les
Insectes,' by M. George Pouchet, 'Revue des Deux Mondes,' Feb. 1870, p.
682.)  On the whole, the difference in mental power between an ant and a
coccus is immense; yet no one has ever dreamed of placing these insects in
distinct classes, much less in distinct kingdoms.  No doubt the difference
is bridged over by other insects; and this is not the case with man and the
higher apes.  But we have every reason to believe that the breaks in the
series are simply the results of many forms having become extinct.

Professor Owen, relying chiefly on the structure of the brain, has divided
the mammalian series into four sub-classes.  One of these he devotes to
man; in another he places both the marsupials and the Monotremata; so that
he makes man as distinct from all other mammals as are these two latter
groups conjoined.  This view has not been accepted, as far as I am aware,
by any naturalist capable of forming an independent judgment, and therefore
need not here be further considered.

We can understand why a classification founded on any single character or
organ--even an organ so wonderfully complex and important as the brain--or
on the high development of the mental faculties, is almost sure to prove
unsatisfactory.  This principle has indeed been tried with hymenopterous
insects; but when thus classed by their habits or instincts, the
arrangement proved thoroughly artificial.  (3.  Westwood, 'Modern
Classification of Insects,' vol. ii. 1840, p. 87.)  Classifications may, of
course, be based on any character whatever, as on size, colour, or the
element inhabited; but naturalists have long felt a profound conviction
that there is a natural system.  This system, it is now generally admitted,
must be, as far as possible, genealogical in arrangement,--that is, the co-
descendants of the same form must be kept together in one group, apart from
the co-descendants of any other form; but if the parent-forms are related,
so will be their descendants, and the two groups together will form a
larger group.  The amount of difference between the several groups--that is
the amount of modification which each has undergone--is expressed by such
terms as genera, families, orders, and classes.  As we have no record of
the lines of descent, the pedigree can be discovered only by observing the
degrees of resemblance between the beings which are to be classed.  For
this object numerous points of resemblance are of much more importance than
the amount of similarity or dissimilarity in a few points.  If two
languages were found to resemble each other in a multitude of words and
points of construction, they would be universally recognised as having
sprung from a common source, notwithstanding that they differed greatly in
some few words or points of construction.  But with organic beings the
points of resemblance must not consist of adaptations to similar habits of
life:  two animals may, for instance, have had their whole frames modified
for living in the water, and yet they will not be brought any nearer to
each other in the natural system.  Hence we can see how it is that
resemblances in several unimportant structures, in useless and rudimentary
organs, or not now functionally active, or in an embryological condition,
are by far the most serviceable for classification; for they can hardly be
due to adaptations within a late period; and thus they reveal the old lines
of descent or of true affinity.

We can further see why a great amount of modification in some one character
ought not to lead us to separate widely any two organisms.  A part which
already differs much from the same part in other allied forms has already,
according to the theory of evolution, varied much; consequently it would
(as long as the organism remained exposed to the same exciting conditions)
be liable to further variations of the same kind; and these, if beneficial,
would be preserved, and thus be continually augmented.  In many cases the
continued development of a part, for instance, of the beak of a bird, or of
the teeth of a mammal, would not aid the species in gaining its food, or
for any other object; but with man we can see no definite limit to the
continued development of the brain and mental faculties, as far as
advantage is concerned.  Therefore in determining the position of man in
the natural or genealogical system, the extreme development of his brain
ought not to outweigh a multitude of resemblances in other less important
or quite unimportant points.

The greater number of naturalists who have taken into consideration the
whole structure of man, including his mental faculties, have followed
Blumenbach and Cuvier, and have placed man in a separate Order, under the
title of the Bimana, and therefore on an equality with the orders of the
Quadrumana, Carnivora, etc.  Recently many of our best naturalists have
recurred to the view first propounded by Linnaeus, so remarkable for his
sagacity, and have placed man in the same Order with the Quadrumana, under
the title of the Primates.  The justice of this conclusion will be
admitted:  for in the first place, we must bear in mind the comparative
insignificance for classification of the great development of the brain in
man, and that the strongly-marked differences between the skulls of man and
the Quadrumana (lately insisted upon by Bischoff, Aeby, and others)
apparently follow from their differently developed brains.  In the second
place, we must remember that nearly all the other and more important
differences between man and the Quadrumana are manifestly adaptive in their
nature, and relate chiefly to the erect position of man; such as the
structure of his hand, foot, and pelvis, the curvature of his spine, and
the position of his head.  The family of Seals offers a good illustration
of the small importance of adaptive characters for classification.  These
animals differ from all other Carnivora in the form of their bodies and in
the structure of their limbs, far more than does man from the higher apes;
yet in most systems, from that of Cuvier to the most recent one by Mr.
Flower (4.  'Proceedings Zoological Society,' 1863, p. 4.), seals are
ranked as a mere family in the Order of the Carnivora.  If man had not been
his own classifier, he would never have thought of founding a separate
order for his own reception.

It would be beyond my limits, and quite beyond my knowledge, even to name
the innumerable points of structure in which man agrees with the other
Primates.  Our great anatomist and philosopher, Prof. Huxley, has fully
discussed this subject (5.  'Evidence as to Man's Place in Nature,' 1863,
p. 70, et passim.), and concludes that man in all parts of his organization
differs less from the higher apes, than these do from the lower members of
the same group.  Consequently there "is no justification for placing man in
a distinct order."

In an early part of this work I brought forward various facts, shewing how
closely man agrees in constitution with the higher mammals; and this
agreement must depend on our close similarity in minute structure and
chemical composition.  I gave, as instances, our liability to the same
diseases, and to the attacks of allied parasites; our tastes in common for
the same stimulants, and the similar effects produced by them, as well as
by various drugs, and other such facts.

As small unimportant points of resemblance between man and the Quadrumana
are not commonly noticed in systematic works, and as, when numerous, they
clearly reveal our relationship, I will specify a few such points.  The
relative position of our features is manifestly the same; and the various
emotions are displayed by nearly similar movements of the muscles and skin,
chiefly above the eyebrows and round the mouth.  Some few expressions are,
indeed, almost the same, as in the weeping of certain kinds of monkeys and
in the laughing noise made by others, during which the corners of the mouth
are drawn backwards, and the lower eyelids wrinkled.  The external ears are
curiously alike.  In man the nose is much more prominent than in most
monkeys; but we may trace the commencement of an aquiline curvature in the
nose of the Hoolock Gibbon; and this in the Semnopithecus nasica is carried
to a ridiculous extreme.

The faces of many monkeys are ornamented with beards, whiskers, or
moustaches.  The hair on the head grows to a great length in some species
of Semnopithecus (6.  Isidore Geoffroy St.-Hilaire, 'Hist. Nat. Gen.' tom.
ii. 1859, p. 217.); and in the Bonnet monkey (Macacus radiatus) it radiates
from a point on the crown, with a parting down the middle.  It is commonly
said that the forehead gives to man his noble and intellectual appearance;
but the thick hair on the head of the Bonnet monkey terminates downwards
abruptly, and is succeeded by hair so short and fine that at a little
distance the forehead, with the exception of the eyebrows, appears quite
naked.  It has been erroneously asserted that eyebrows are not present in
any monkey.  In the species just named the degree of nakedness of the
forehead differs in different individuals; and Eschricht states (7.  'Ueber
die Richtung der Haare,' etc., Mueller's 'Archiv fur Anat. und Phys.' 1837,
s. 51.) that in our children the limit between the hairy scalp and the
naked forehead is sometimes not well defined; so that here we seem to have
a trifling case of reversion to a progenitor, in whom the forehead had not
as yet become quite naked.

It is well known that the hair on our arms tends to converge from above and
below to a point at the elbow.  This curious arrangement, so unlike that in
most of the lower mammals, is common to the gorilla, chimpanzee, orang,
some species of Hylobates, and even to some few American monkeys.  But in
Hylobates agilis the hair on the fore-arm is directed downwards or towards
the wrist in the ordinary manner; and in H. lar it is nearly erect, with
only a very slight forward inclination; so that in this latter species it
is in a transitional state.  It can hardly be doubted that with most
mammals the thickness of the hair on the back and its direction, is adapted
to throw off the rain; even the transverse hairs on the fore-legs of a dog
may serve for this end when he is coiled up asleep.  Mr. Wallace, who has
carefully studied the habits of the orang, remarks that the convergence of
the hair towards the elbow on the arms of the orang may be explained as
serving to throw off the rain, for this animal during rainy weather sits
with its arms bent, and with the hands clasped round a branch or over its
head.  According to Livingstone, the gorilla also "sits in pelting rain
with his hands over his head."  (8.  Quoted by Reade, 'The African Sketch
Book,' vol i. 1873, p. 152.)  If the above explanation is correct, as seems
probable, the direction of the hair on our own arms offers a curious record
of our former state; for no one supposes that it is now of any use in
throwing off the rain; nor, in our present erect condition, is it properly
directed for this purpose.

It would, however, be rash to trust too much to the principle of adaptation
in regard to the direction of the hair in man or his early progenitors; for
it is impossible to study the figures given by Eschricht of the arrangement
of the hair on the human foetus (this being the same as in the adult) and
not agree with this excellent observer that other and more complex causes
have intervened.  The points of convergence seem to stand in some relation
to those points in the embryo which are last closed in during development.
There appears, also, to exist some relation between the arrangement of the
hair on the limbs, and the course of the medullary arteries. (9.  On the
hair in Hylobates, see 'Natural History of Mammals,' by C.L. Martin, 1841,
p. 415.  Also, Isidore Geoffroy on the American monkeys and other kinds,
'Hist. Nat. Gen.' vol. ii. 1859, pp. 216, 243.  Eschricht, ibid. s. 46, 55,
61.  Owen, 'Anatomy of Vertebrates,' vol. iii. p. 619.  Wallace,
'Contributions to the Theory of Natural Selection,' 1870, p. 344.)

It must not be supposed that the resemblances between man and certain apes
in the above and in many other points--such as in having a naked forehead,
long tresses on the head, etc.,--are all necessarily the result of unbroken
inheritance from a common progenitor, or of subsequent reversion.  Many of
these resemblances are more probably due to analogous variation, which
follows, as I have elsewhere attempted to shew (10.  'Origin of Species,'
5th edit. 1869, p.194.  'The Variation of Animals and Plants under
Domestication,' vol. ii. 1868, p. 348.), from co-descended organisms having
a similar constitution, and having been acted on by like causes inducing
similar modifications.  With respect to the similar direction of the hair
on the fore-arms of man and certain monkeys, as this character is common to
almost all the anthropomorphous apes, it may probably be attributed to
inheritance; but this is not certain, as some very distinct American
monkeys are thus characterised.

Although, as we have now seen, man has no just right to form a separate
Order for his own reception, he may perhaps claim a distinct Sub-order or
Family.  Prof. Huxley, in his last work (11.  'An Introduction to the
Classification of Animals,' 1869, p. 99.), divides the primates into three
Sub-orders; namely, the Anthropidae with man alone, the Simiadae including
monkeys of all kinds, and the Lemuridae with the diversified genera of
lemurs.  As far as differences in certain important points of structure are
concerned, man may no doubt rightly claim the rank of a Sub-order; and this
rank is too low, if we look chiefly to his mental faculties.  Nevertheless,
from a genealogical point of view it appears that this rank is too high,
and that man ought to form merely a Family, or possibly even only a Sub-
family.  If we imagine three lines of descent proceeding from a common
stock, it is quite conceivable that two of them might after the lapse of
ages be so slightly changed as still to remain as species of the same
genus, whilst the third line might become so greatly modified as to deserve
to rank as a distinct Sub-family, Family, or even Order.  But in this case
it is almost certain that the third line would still retain through
inheritance numerous small points of resemblance with the other two.  Here,
then, would occur the difficulty, at present insoluble, how much weight we
ought to assign in our classifications to strongly-marked differences in
some few points,--that is, to the amount of modification undergone; and how
much to close resemblance in numerous unimportant points, as indicating the
lines of descent or genealogy.  To attach much weight to the few but strong
differences is the most obvious and perhaps the safest course, though it
appears more correct to pay great attention to the many small resemblances,
as giving a truly natural classification.

In forming a judgment on this head with reference to man, we must glance at
the classification of the Simiadae.  This family is divided by almost all
naturalists into the Catarrhine group, or Old World monkeys, all of which
are characterised (as their name expresses) by the peculiar structure of
their nostrils, and by having four premolars in each jaw; and into the
Platyrrhine group or New World monkeys (including two very distinct sub-
groups), all of which are characterised by differently constructed
nostrils, and by having six premolars in each jaw.  Some other small
differences might be mentioned.  Now man unquestionably belongs in his
dentition, in the structure of his nostrils, and some other respects, to
the Catarrhine or Old World division; nor does he resemble the Platyrrhines
more closely than the Catarrhines in any characters, excepting in a few of
not much importance and apparently of an adaptive nature.  It is therefore
against all probability that some New World species should have formerly
varied and produced a man-like creature, with all the distinctive
characters proper to the Old World division; losing at the same time all
its own distinctive characters.  There can, consequently, hardly be a doubt
that man is an off-shoot from the Old World Simian stem; and that under a
genealogical point of view he must be classed with the Catarrhine division.
(12.  This is nearly the same classification as that provisionally adopted
by Mr. St. George Mivart, ('Transactions, Philosophical Society," 1867, p.
300), who, after separating the Lemuridae, divides the remainder of the
Primates into the Hominidae, the Simiadae which answer to the Catarrhines,
the Cebidae, and the Hapalidae,--these two latter groups answering to the
Platyrrhines.  Mr. Mivart still abides by the same view; see 'Nature,'
1871, p. 481.)

The anthropomorphous apes, namely the gorilla, chimpanzee, orang, and
hylobates, are by most naturalists separated from the other Old World
monkeys, as a distinct sub-group.  I am aware that Gratiolet, relying on
the structure of the brain, does not admit the existence of this sub-group,
and no doubt it is a broken one.  Thus the orang, as Mr. St. G. Mivart
remarks, "is one of the most peculiar and aberrant forms to be found in the
Order."  (13.  'Transactions, Zoolog. Soc.' vol. vi. 1867, p. 214.)  The
remaining non-anthropomorphous Old World monkeys, are again divided by some
naturalists into two or three smaller sub-groups; the genus Semnopithecus,
with its peculiar sacculated stomach, being the type of one sub-group.  But
it appears from M. Gaudry's wonderful discoveries in Attica, that during
the Miocene period a form existed there, which connected Semnopithecus and
Macacus; and this probably illustrates the manner in which the other and
higher groups were once blended together.

If the anthropomorphous apes be admitted to form a natural sub-group, then
as man agrees with them, not only in all those characters which he
possesses in common with the whole Catarrhine group, but in other peculiar
characters, such as the absence of a tail and of callosities, and in
general appearance, we may infer that some ancient member of the
anthropomorphous sub-group gave birth to man.  It is not probable that,
through the law of analogous variation, a member of one of the other lower
sub-groups should have given rise to a man-like creature, resembling the
higher anthropomorphous apes in so many respects.  No doubt man, in
comparison with most of his allies, has undergone an extraordinary amount
of modification, chiefly in consequence of the great development of his
brain and his erect position; nevertheless, we should bear in mind that he
"is but one of several exceptional forms of Primates."  (14.  Mr. St. G.
Mivart, 'Transactions of the Philosophical Society,' 1867, p. 410.)

Every naturalist, who believes in the principle of evolution, will grant
that the two main divisions of the Simiadae, namely the Catarrhine and
Platyrrhine monkeys, with their sub-groups, have all proceeded from some
one extremely ancient progenitor.  The early descendants of this
progenitor, before they had diverged to any considerable extent from each
other, would still have formed a single natural group; but some of the
species or incipient genera would have already begun to indicate by their
diverging characters the future distinctive marks of the Catarrhine and
Platyrrhine divisions.  Hence the members of this supposed ancient group
would not have been so uniform in their dentition, or in the structure of
their nostrils, as are the existing Catarrhine monkeys in one way and the
Platyrrhines in another way, but would have resembled in this respect the
allied Lemuridae, which differ greatly from each other in the form of their
muzzles (15.  Messrs. Murie and Mivart on the Lemuroidea, 'Transactions,
Zoological Society,' vol. vii, 1869, p. 5.), and to an extraordinary degree
in their dentition.

The Catarrhine and Platyrrhine monkeys agree in a multitude of characters,
as is shewn by their unquestionably belonging to one and the same Order.
The many characters which they possess in common can hardly have been
independently acquired by so many distinct species; so that these
characters must have been inherited.  But a naturalist would undoubtedly
have ranked as an ape or a monkey, an ancient form which possessed many
characters common to the Catarrhine and Platyrrhine monkeys, other
characters in an intermediate condition, and some few, perhaps, distinct
from those now found in either group.  And as man from a genealogical point
of view belongs to the Catarrhine or Old World stock, we must conclude,
however much the conclusion may revolt our pride, that our early
progenitors would have been properly thus designated.  (16.  Haeckel has
come to this same conclusion.  See 'Ueber die Entstehung des
Menschengeschlechts,' in Virchow's 'Sammlung. gemein. wissen. Vortraege,'
1868, s. 61.  Also his 'Natuerliche Schoepfungsgeschichte,' 1868, in which he
gives in detail his views on the genealogy of man.)  But we must not fall
into the error of supposing that the early progenitor of the whole Simian
stock, including man, was identical with, or even closely resembled, any
existing ape or monkey.

ON THE BIRTHPLACE AND ANTIQUITY OF MAN.

We are naturally led to enquire, where was the birthplace of man at that
stage of descent when our progenitors diverged from the Catarrhine stock?
The fact that they belonged to this stock clearly shews that they inhabited
the Old World; but not Australia nor any oceanic island, as we may infer
from the laws of geographical distribution.  In each great region of the
world the living mammals are closely related to the extinct species of the
same region.  It is therefore probable that Africa was formerly inhabited
by extinct apes closely allied to the gorilla and chimpanzee; and as these
two species are now man's nearest allies, it is somewhat more probable that
our early progenitors lived on the African continent than elsewhere.  But
it is useless to speculate on this subject; for two or three
anthropomorphous apes, one the Dryopithecus (17.  Dr. C. Forsyth Major,
'Sur les Singes fossiles trouves en Italie:' 'Soc. Ital. des Sc. Nat.' tom.
xv. 1872.) of Lartet, nearly as large as a man, and closely allied to
Hylobates, existed in Europe during the Miocene age; and since so remote a
period the earth has certainly undergone many great revolutions, and there
has been ample time for migration on the largest scale.

At the period and place, whenever and wherever it was, when man first lost
his hairy covering, he probably inhabited a hot country; a circumstance
favourable for the frugiferous diet on which, judging from analogy, he
subsisted.  We are far from knowing how long ago it was when man first
diverged from the Catarrhine stock; but it may have occurred at an epoch as
remote as the Eocene period; for that the higher apes had diverged from the
lower apes as early as the Upper Miocene period is shewn by the existence
of the Dryopithecus.  We are also quite ignorant at how rapid a rate
organisms, whether high or low in the scale, may be modified under
favourable circumstances; we know, however, that some have retained the
same form during an enormous lapse of time.  From what we see going on
under domestication, we learn that some of the co-descendants of the same
species may be not at all, some a little, and some greatly changed, all
within the same period.  Thus it may have been with man, who has undergone
a great amount of modification in certain characters in comparison with the
higher apes.

The great break in the organic chain between man and his nearest allies,
which cannot be bridged over by any extinct or living species, has often
been advanced as a grave objection to the belief that man is descended from
some lower form; but this objection will not appear of much weight to those
who, from general reasons, believe in the general principle of evolution.
Breaks often occur in all parts of the series, some being wide, sharp and
defined, others less so in various degrees; as between the orang and its
nearest allies--between the Tarsius and the other Lemuridae--between the
elephant, and in a more striking manner between the Ornithorhynchus or
Echidna, and all other mammals.  But these breaks depend merely on the
number of related forms which have become extinct.  At some future period,
not very distant as measured by centuries, the civilised races of man will
almost certainly exterminate, and replace, the savage races throughout the
world.  At the same time the anthropomorphous apes, as Professor
Schaaffhausen has remarked (18.  'Anthropological Review,' April 1867, p.
236.), will no doubt be exterminated.  The break between man and his
nearest allies will then be wider, for it will intervene between man in a
more civilised state, as we may hope, even than the Caucasian, and some ape
as low as a baboon, instead of as now between the negro or Australian and
the gorilla.

With respect to the absence of fossil remains, serving to connect man with
his ape-like progenitors, no one will lay much stress on this fact who
reads Sir C. Lyell's discussion (19.  'Elements of Geology,' 1865, pp. 583-
585.  'Antiquity of Man,' 1863, p. 145.), where he shews that in all the
vertebrate classes the discovery of fossil remains has been a very slow and
fortuitous process.  Nor should it be forgotten that those regions which
are the most likely to afford remains connecting man with some extinct ape-
like creature, have not as yet been searched by geologists.

LOWER STAGES IN THE GENEALOGY OF MAN.

We have seen that man appears to have diverged from the Catarrhine or Old
World division of the Simiadae, after these had diverged from the New World
division.  We will now endeavour to follow the remote traces of his
genealogy, trusting principally to the mutual affinities between the
various classes and orders, with some slight reference to the periods, as
far as ascertained, of their successive appearance on the earth.  The
Lemuridae stand below and near to the Simiadae, and constitute a very
distinct family of the primates, or, according to Haeckel and others, a
distinct Order.  This group is diversified and broken to an extraordinary
degree, and includes many aberrant forms.  It has, therefore, probably
suffered much extinction.  Most of the remnants survive on islands, such as
Madagascar and the Malayan archipelago, where they have not been exposed to
so severe a competition as they would have been on well-stocked continents.
This group likewise presents many gradations, leading, as Huxley remarks
(20.  'Man's Place in Nature,' p. 105.), "insensibly from the crown and
summit of the animal creation down to creatures from which there is but a
step, as it seems, to the lowest, smallest, and least intelligent of the
placental mammalia."  From these various considerations it is probable that
the Simiadae were originally developed from the progenitors of the existing
Lemuridae; and these in their turn from forms standing very low in the
mammalian series.

The Marsupials stand in many important characters below the placental
mammals.  They appeared at an earlier geological period, and their range
was formerly much more extensive than at present.  Hence the Placentata are
generally supposed to have been derived from the Implacentata or
Marsupials; not, however, from forms closely resembling the existing
Marsupials, but from their early progenitors.  The Monotremata are plainly
allied to the Marsupials, forming a third and still lower division in the
great mammalian series.  They are represented at the present day solely by
the Ornithorhynchus and Echidna; and these two forms may be safely
considered as relics of a much larger group, representatives of which have
been preserved in Australia through some favourable concurrence of
circumstances.  The Monotremata are eminently interesting, as leading in
several important points of structure towards the class of reptiles.

In attempting to trace the genealogy of the Mammalia, and therefore of man,
lower down in the series, we become involved in greater and greater
obscurity; but as a most capable judge, Mr. Parker, has remarked, we have
good reason to believe, that no true bird or reptile intervenes in the
direct line of descent.  He who wishes to see what ingenuity and knowledge
can effect, may consult Prof. Haeckel's works.  (21.  Elaborate tables are
given in his 'Generelle Morphologie' (B. ii. s. cliii. and s. 425); and
with more especial reference to man in his 'Natuerliche
Schoepfungsgeschichte,' 1868.  Prof. Huxley, in reviewing this latter work
('The Academy,' 1869, p. 42) says, that he considers the phylum or lines of
descent of the Vertebrata to be admirably discussed by Haeckel, although he
differs on some points.  He expresses, also, his high estimate of the
general tenor and spirit of the whole work.)  I will content myself with a
few general remarks.  Every evolutionist will admit that the five great
vertebrate classes, namely, mammals, birds, reptiles, amphibians, and
fishes, are descended from some one prototype; for they have much in
common, especially during their embryonic state.  As the class of fishes is
the most lowly organised, and appeared before the others, we may conclude
that all the members of the vertebrate kingdom are derived from some
fishlike animal.  The belief that animals so distinct as a monkey, an
elephant, a humming-bird, a snake, a frog, and a fish, etc., could all have
sprung from the same parents, will appear monstrous to those who have not
attended to the recent progress of natural history.  For this belief
implies the former existence of links binding closely together all these
forms, now so utterly unlike.

Nevertheless, it is certain that groups of animals have existed, or do now
exist, which serve to connect several of the great vertebrate classes more
or less closely.  We have seen that the Ornithorhynchus graduates towards
reptiles; and Prof. Huxley has discovered, and is confirmed by Mr. Cope and
others, that the Dinosaurians are in many important characters intermediate
between certain reptiles and certain birds--the birds referred to being the
ostrich-tribe (itself evidently a widely-diffused remnant of a larger
group) and the Archeopteryx, that strange Secondary bird, with a long
lizard-like tail.  Again, according to Prof. Owen (22.  'Palaeontology'
1860, p. 199.), the Ichthyosaurians--great sea-lizards furnished with
paddles--present many affinities with fishes, or rather, according to
Huxley, with amphibians; a class which, including in its highest division
frogs and toads, is plainly allied to the Ganoid fishes.  These latter
fishes swarmed during the earlier geological periods, and were constructed
on what is called a generalised type, that is, they presented diversified
affinities with other groups of organisms.  The Lepidosiren is also so
closely allied to amphibians and fishes, that naturalists long disputed in
which of these two classes to rank it; it, and also some few Ganoid fishes,
have been preserved from utter extinction by inhabiting rivers, which are
harbours of refuge, and are related to the great waters of the ocean in the
same way that islands are to continents.

Lastly, one single member of the immense and diversified class of fishes,
namely, the lancelet or amphioxus, is so different from all other fishes,
that Haeckel maintains that it ought to form a distinct class in the
vertebrate kingdom.  This fish is remarkable for its negative characters;
it can hardly be said to possess a brain, vertebral column, or heart, etc.;
so that it was classed by the older naturalists amongst the worms.  Many
years ago Prof. Goodsir perceived that the lancelet presented some
affinities with the Ascidians, which are invertebrate, hermaphrodite,
marine creatures permanently attached to a support.  They hardly appear
like animals, and consist of a simple, tough, leathery sack, with two small
projecting orifices.  They belong to the Mulluscoida of Huxley--a lower
division of the great kingdom of the Mollusca; but they have recently been
placed by some naturalists amongst the Vermes or worms.  Their larvae
somewhat resemble tadpoles in shape (23.  At the Falkland Islands I had the
satisfaction of seeing, in April, 1833, and therefore some years before any
other naturalist, the locomotive larvae of a compound Ascidian, closely
allied to Synoicum, but apparently generically distinct from it.  The tail
was about five times as long as the oblong head, and terminated in a very
fine filament.  It was, as sketched by me under a simple microscope,
plainly divided by transverse opaque partitions, which I presume represent
the great cells figured by Kovalevsky.  At an early stage of development
the tail was closely coiled round the head of the larva.), and have the
power of swimming freely about.  Mr. Kovalevsky (24.  'Memoires de l'Acad.
des Sciences de St. Petersbourg,' tom. x. No. 15, 1866.) has lately
observed that the larvae of Ascidians are related to the Vertebrata, in
their manner of development, in the relative position of the nervous
system, and in possessing a structure closely like the chorda dorsalis of
vertebrate animals; and in this he has been since confirmed by Prof.
Kupffer.  M. Kovalevsky writes to me from Naples, that he has now carried
these observations yet further, and should his results be well established,
the whole will form a discovery of the very greatest value.  Thus, if we
may rely on embryology, ever the safest guide in classification, it seems
that we have at last gained a clue to the source whence the Vertebrata were
derived.  (25.  But I am bound to add that some competent judges dispute
this conclusion; for instance, M. Giard, in a series of papers in the
'Archives de Zoologie Experimentale,' for 1872.  Nevertheless, this
naturalist remarks, p. 281, "L'organisation de la larve ascidienne en
dehors de toute hypothese et de toute theorie, nous montre comment la
nature peut produire la disposition fondamentale du type vertebre
(l'existence d'une corde dorsale) chez un invertebre par la seule condition
vitale de l'adaptation, et cette simple possibilite du passage supprime
l'abime entre les deux sous-regnes, encore bien qu'en ignore par ou le
passage s'est fait en realite.")  We should then be justified in believing
that at an extremely remote period a group of animals existed, resembling
in many respects the larvae of our present Ascidians, which diverged into
two great branches--the one retrograding in development and producing the
present class of Ascidians, the other rising to the crown and summit of the
animal kingdom by giving birth to the Vertebrata.

We have thus far endeavoured rudely to trace the genealogy of the
Vertebrata by the aid of their mutual affinities.  We will now look to man
as he exists; and we shall, I think, be able partially to restore the
structure of our early progenitors, during successive periods, but not in
due order of time.  This can be effected by means of the rudiments which
man still retains, by the characters which occasionally make their
appearance in him through reversion, and by the aid of the principles of
morphology and embryology.  The various facts, to which I shall here
allude, have been given in the previous chapters.

The early progenitors of man must have been once covered with hair, both
sexes having beards; their ears were probably pointed, and capable of
movement; and their bodies were provided with a tail, having the proper
muscles.  Their limbs and bodies were also acted on by many muscles which
now only occasionally reappear, but are normally present in the Quadrumana.
At this or some earlier period, the great artery and nerve of the humerus
ran through a supra-condyloid foramen.  The intestine gave forth a much
larger diverticulum or caecum than that now existing.  The foot was then
prehensile, judging from the condition of the great toe in the foetus; and
our progenitors, no doubt, were arboreal in their habits, and frequented
some warm, forest-clad land.  The males had great canine teeth, which
served them as formidable weapons.  At a much earlier period the uterus was
double; the excreta were voided through a cloaca; and the eye was protected
by a third eyelid or nictitating membrane.  At a still earlier period the
progenitors of man must have been aquatic in their habits; for morphology
plainly tells us that our lungs consist of a modified swim-bladder, which
once served as a float.  The clefts on the neck in the embryo of man shew
where the branchiae once existed.  In the lunar or weekly recurrent periods
of some of our functions we apparently still retain traces of our
primordial birthplace, a shore washed by the tides.  At about this same
early period the true kidneys were replaced by the corpora wolffiana.  The
heart existed as a simple pulsating vessel; and the chorda dorsalis took
the place of a vertebral column.  These early ancestors of man, thus seen
in the dim recesses of time, must have been as simply, or even still more
simply organised than the lancelet or amphioxus.

There is one other point deserving a fuller notice.  It has long been known
that in the vertebrate kingdom one sex bears rudiments of various accessory
parts, appertaining to the reproductive system, which properly belong to
the opposite sex; and it has now been ascertained that at a very early
embryonic period both sexes possess true male and female glands.  Hence
some remote progenitor of the whole vertebrate kingdom appears to have been
hermaphrodite or androgynous.  (26.  This is the conclusion of Prof.
Gegenbaur, one of the highest authorities in comparative anatomy:  see
'Grundzuege der vergleich. Anat.' 1870, s. 876.  The result has been arrived
at chiefly from the study of the Amphibia; but it appears from the
researches of Waldeyer (as quoted in 'Journal of Anat. and Phys.' 1869, p.
161), that the sexual organs of even "the higher vertebrata are, in their
early condition, hermaphrodite."  Similar views have long been held by some
authors, though until recently without a firm basis.)  But here we
encounter a singular difficulty.  In the mammalian class the males possess
rudiments of a uterus with the adjacent passage, in their vesiculae
prostaticae; they bear also rudiments of mammae, and some male Marsupials
have traces of a marsupial sack.  (27.  The male Thylacinus offers the best
instance.  Owen, 'Anatomy of Vertebrates,' vol. iii. p. 771.)  Other
analogous facts could be added.  Are we, then, to suppose that some
extremely ancient mammal continued androgynous, after it had acquired the
chief distinctions of its class, and therefore after it had diverged from
the lower classes of the vertebrate kingdom?  This seems very improbable,
for we have to look to fishes, the lowest of all the classes, to find any
still existent androgynous forms.  (28.  Hermaphroditism has been observed
in several species of Serranus, as well as in some other fishes, where it
is either normal and symmetrical, or abnormal and unilateral.  Dr.
Zouteveen has given me references on this subject, more especially to a
paper by Prof. Halbertsma, in the 'Transact. of the Dutch Acad. of
Sciences,' vol. xvi.  Dr. Gunther doubts the fact, but it has now been
recorded by too many good observers to be any longer disputed.  Dr. M.
Lessona writes to me, that he has verified the observations made by
Cavolini on Serranus.  Prof. Ercolani has recently shewn ('Accad. delle
Scienze,' Bologna, Dec. 28, 1871) that eels are androgynous.)  That various
accessory parts, proper to each sex, are found in a rudimentary condition
in the opposite sex, may be explained by such organs having been gradually
acquired by the one sex, and then transmitted in a more or less imperfect
state to the other.  When we treat of sexual selection, we shall meet with
innumerable instances of this form of transmission,--as in the case of the
spurs, plumes, and brilliant colours, acquired for battle or ornament by
male birds, and inherited by the females in an imperfect or rudimentary
condition.

The possession by male mammals of functionally imperfect mammary organs is,
in some respects, especially curious.  The Monotremata have the proper
milk-secreting glands with orifices, but no nipples; and as these animals
stand at the very base of the mammalian series, it is probable that the
progenitors of the class also had milk-secreting glands, but no nipples.
This conclusion is supported by what is known of their manner of
development; for Professor Turner informs me, on the authority of Kolliker
and Langer, that in the embryo the mammary glands can be distinctly traced
before the nipples are in the least visible; and the development of
successive parts in the individual generally represents and accords with
the development of successive beings in the same line of descent.  The
Marsupials differ from the Monotremata by possessing nipples; so that
probably these organs were first acquired by the Marsupials, after they had
diverged from, and risen above, the Monotremata, and were then transmitted
to the placental mammals.  (29.  Prof. Gegenbaur has shewn ('Jenaeische
Zeitschrift,' Bd. vii. p. 212) that two distinct types of nipples prevail
throughout the several mammalian orders, but that it is quite intelligible
how both could have been derived from the nipples of the Marsupials, and
the latter from those of the Monotremata.  See, also, a memoir by Dr. Max
Huss, on the mammary glands, ibid. B. viii. p. 176.)  No one will suppose
that the marsupials still remained androgynous, after they had
approximately acquired their present structure.  How then are we to account
for male mammals possessing mammae?  It is possible that they were first
developed in the females and then transferred to the males, but from what
follows this is hardly probable.

It may be suggested, as another view, that long after the progenitors of
the whole mammalian class had ceased to be androgynous, both sexes yielded
milk, and thus nourished their young; and in the case of the Marsupials,
that both sexes carried their young in marsupial sacks.  This will not
appear altogether improbable, if we reflect that the males of existing
syngnathous fishes receive the eggs of the females in their abdominal
pouches, hatch them, and afterwards, as some believe, nourish the young
(30.  Mr. Lockwood believes (as quoted in 'Quart. Journal of Science,'
April 1868, p. 269), from what he has observed of the development of
Hippocampus, that the walls of the abdominal pouch of the male in some way
afford nourishment.  On male fishes hatching the ova in their mouths, see a
very interesting paper by Prof. Wyman, in 'Proc. Boston Soc. of Nat. Hist.'
Sept. 15, 1857; also Prof. Turner, in 'Journal of Anatomy and Physiology,'
Nov. 1, 1866, p. 78.  Dr. Gunther has likewise described similar cases.);--
that certain other male fishes hatch the eggs within their mouths or
branchial cavities;--that certain male toads take the chaplets of eggs from
the females, and wind them round their own thighs, keeping them there until
the tadpoles are born;--that certain male birds undertake the whole duty of
incubation, and that male pigeons, as well as the females, feed their
nestlings with a secretion from their crops.  But the above suggestion
first occurred to me from mammary glands of male mammals being so much more
perfectly developed than the rudiments of the other accessory reproductive
parts, which are found in the one sex though proper to the other.  The
mammary glands and nipples, as they exist in male mammals, can indeed
hardly be called rudimentary; they are merely not fully developed, and not
functionally active.  They are sympathetically affected under the influence
of certain diseases, like the same organs in the female.  They often
secrete a few drops of milk at birth and at puberty:  this latter fact
occurred in the curious case, before referred to, where a young man
possessed two pairs of mammae.  In man and some other male mammals these
organs have been known occasionally to become so well developed during
maturity as to yield a fair supply of milk.  Now if we suppose that during
a former prolonged period male mammals aided the females in nursing their
offspring (31.  Mlle. C. Royer has suggested a similar view in her 'Origine
de l'homme,' etc., 1870.), and that afterwards from some cause (as from the
production of a smaller number of young) the males ceased to give this aid,
disuse of the organs during maturity would lead to their becoming inactive;
and from two well-known principles of inheritance, this state of inactivity
would probably be transmitted to the males at the corresponding age of
maturity.  But at an earlier age these organs would be left unaffected, so
that they would be almost equally well developed in the young of both
sexes.

CONCLUSION.

Von Baer has defined advancement or progress in the organic scale better
than any one else, as resting on the amount of differentiation and
specialisation of the several parts of a being,--when arrived at maturity,
as I should be inclined to add.  Now as organisms have become slowly
adapted to diversified lines of life by means of natural selection, their
parts will have become more and more differentiated and specialised for
various functions from the advantage gained by the division of
physiological labour.  The same part appears often to have been modified
first for one purpose, and then long afterwards for some other and quite
distinct purpose; and thus all the parts are rendered more and more
complex.  But each organism still retains the general type of structure of
the progenitor from which it was aboriginally derived.  In accordance with
this view it seems, if we turn to geological evidence, that organisation on
the whole has advanced throughout the world by slow and interrupted steps.
In the great kingdom of the Vertebrata it has culminated in man.  It must
not, however, be supposed that groups of organic beings are always
supplanted, and disappear as soon as they have given birth to other and
more perfect groups.  The latter, though victorious over their
predecessors, may not have become better adapted for all places in the
economy of nature.  Some old forms appear to have survived from inhabiting
protected sites, where they have not been exposed to very severe
competition; and these often aid us in constructing our genealogies, by
giving us a fair idea of former and lost populations.  But we must not fall
into the error of looking at the existing members of any lowly-organised
group as perfect representatives of their ancient predecessors.

The most ancient progenitors in the kingdom of the Vertebrata, at which we
are able to obtain an obscure glance, apparently consisted of a group of
marine animals (32.  The inhabitants of the seashore must be greatly
affected by the tides; animals living either about the MEAN high-water
mark, or about the MEAN low-water mark, pass through a complete cycle of
tidal changes in a fortnight.  Consequently, their food supply will undergo
marked changes week by week.  The vital functions of such animals, living
under these conditions for many generations, can hardly fail to run their
course in regular weekly periods.  Now it is a mysterious fact that in the
higher and now terrestrial Vertebrata, as well as in other classes, many
normal and abnormal processes have one or more whole weeks as their
periods; this would be rendered intelligible if the Vertebrata are
descended from an animal allied to the existing tidal Ascidians.  Many
instances of such periodic processes might be given, as the gestation of
mammals, the duration of fevers, etc.  The hatching of eggs affords also a
good example, for, according to Mr. Bartlett ('Land and Water,' Jan. 7,
1871), the eggs of the pigeon are hatched in two weeks; those of the fowl
in three; those of the duck in four; those of the goose in five; and those
of the ostrich in seven weeks.  As far as we can judge, a recurrent period,
if approximately of the right duration for any process or function, would
not, when once gained, be liable to change; consequently it might be thus
transmitted through almost any number of generations.  But if the function
changed, the period would have to change, and would be apt to change almost
abruptly by a whole week.  This conclusion, if sound, is highly remarkable;
for the period of gestation in each mammal, and the hatching of each bird's
eggs, and many other vital processes, thus betray to us the primordial
birthplace of these animals.), resembling the larvae of existing Ascidians.
These animals probably gave rise to a group of fishes, as lowly organised
as the lancelet; and from these the Ganoids, and other fishes like the
Lepidosiren, must have been developed.  From such fish a very small advance
would carry us on to the Amphibians.  We have seen that birds and reptiles
were once intimately connected together; and the Monotremata now connect
mammals with reptiles in a slight degree.  But no one can at present say by
what line of descent the three higher and related classes, namely, mammals,
birds, and reptiles, were derived from the two lower vertebrate classes,
namely, amphibians and fishes.  In the class of mammals the steps are not
difficult to conceive which led from the ancient Monotremata to the ancient
Marsupials; and from these to the early progenitors of the placental
mammals.  We may thus ascend to the Lemuridae; and the interval is not very
wide from these to the Simiadae.  The Simiadae then branched off into two
great stems, the New World and Old World monkeys; and from the latter, at a
remote period, Man, the wonder and glory of the Universe, proceeded.

Thus we have given to man a pedigree of prodigious length, but not, it may
be said, of noble quality.  The world, it has often been remarked, appears
as if it had long been preparing for the advent of man:  and this, in one
sense is strictly true, for he owes his birth to a long line of
progenitors.  If any single link in this chain had never existed, man would
not have been exactly what he now is.  Unless we wilfully close our eyes,
we may, with our present knowledge, approximately recognise our parentage;
nor need we feel ashamed of it.  The most humble organism is something much
higher than the inorganic dust under our feet; and no one with an unbiassed
mind can study any living creature, however humble, without being struck
with enthusiasm at its marvellous structure and properties.


CHAPTER VII.

ON THE RACES OF MAN.

The nature and value of specific characters--Application to the races of
man--Arguments in favour of, and opposed to, ranking the so-called races of
man as distinct species--Sub-species--Monogenists and polygenists--
Convergence of character--Numerous points of resemblance in body and mind
between the most distinct races of man--The state of man when he first
spread over the earth--Each race not descended from a single pair--The
extinction of races--The formation of races--The effects of crossing--
Slight influence of the direct action of the conditions of life--Slight or
no influence of natural selection--Sexual selection.

It is not my intention here to describe the several so-called races of men;
but I am about to enquire what is the value of the differences between them
under a classificatory point of view, and how they have originated.  In
determining whether two or more allied forms ought to be ranked as species
or varieties, naturalists are practically guided by the following
considerations; namely, the amount of difference between them, and whether
such differences relate to few or many points of structure, and whether
they are of physiological importance; but more especially whether they are
constant.  Constancy of character is what is chiefly valued and sought for
by naturalists.  Whenever it can be shewn, or rendered probable, that the
forms in question have remained distinct for a long period, this becomes an
argument of much weight in favour of treating them as species.  Even a
slight degree of sterility between any two forms when first crossed, or in
their offspring, is generally considered as a decisive test of their
specific distinctness; and their continued persistence without blending
within the same area, is usually accepted as sufficient evidence, either of
some degree of mutual sterility, or in the case of animals of some mutual
repugnance to pairing.

Independently of fusion from intercrossing, the complete absence, in a
well-investigated region, of varieties linking together any two closely-
allied forms, is probably the most important of all the criterions of their
specific distinctness; and this is a somewhat different consideration from
mere constancy of character, for two forms may be highly variable and yet
not yield intermediate varieties.  Geographical distribution is often
brought into play unconsciously and sometimes consciously; so that forms
living in two widely separated areas, in which most of the other
inhabitants are specifically distinct, are themselves usually looked at as
distinct; but in truth this affords no aid in distinguishing geographical
races from so-called good or true species.

Now let us apply these generally-admitted principles to the races of man,
viewing him in the same spirit as a naturalist would any other animal.  In
regard to the amount of difference between the races, we must make some
allowance for our nice powers of discrimination gained by the long habit of
observing ourselves.  In India, as Elphinstone remarks, although a newly-
arrived European cannot at first distinguish the various native races, yet
they soon appear to him extremely dissimilar (1.  'History of India,' 1841,
vol. i. p. 323.  Father Ripa makes exactly the same remark with respect to
the Chinese.); and the Hindoo cannot at first perceive any difference
between the several European nations.  Even the most distinct races of man
are much more like each other in form than would at first be supposed;
certain negro tribes must be excepted, whilst others, as Dr. Rohlfs writes
to me, and as I have myself seen, have Caucasian features.  This general
similarity is well shewn by the French photographs in the Collection
Anthropologique du Museum de Paris of the men belonging to various races,
the greater number of which might pass for Europeans, as many persons to
whom I have shewn them have remarked.  Nevertheless, these men, if seen
alive, would undoubtedly appear very distinct, so that we are clearly much
influenced in our judgment by the mere colour of the skin and hair, by
slight differences in the features, and by expression.

There is, however, no doubt that the various races, when carefully compared
and measured, differ much from each other,--as in the texture of the hair,
the relative proportions of all parts of the body (2.  A vast number of
measurements of Whites, Blacks, and Indians, are given in the
'Investigations in the Military and Anthropolog. Statistics of American
Soldiers,' by B.A. Gould, 1869, pp. 298-358; 'On the capacity of the
lungs,' p. 471.  See also the numerous and valuable tables, by Dr.
Weisbach, from the observations of Dr. Scherzer and Dr. Schwarz, in the
'Reise der Novara:  Anthropolog. Theil,' 1867.), the capacity of the lungs,
the form and capacity of the skull, and even in the convolutions of the
brain.  (3.  See, for instance, Mr. Marshall's account of the brain of a
Bushwoman, in 'Philosophical Transactions,' 1864, p. 519.)  But it would be
an endless task to specify the numerous points of difference.  The races
differ also in constitution, in acclimatisation and in liability to certain
diseases.  Their mental characteristics are likewise very distinct; chiefly
as it would appear in their emotional, but partly in their intellectual
faculties.  Every one who has had the opportunity of comparison, must have
been struck with the contrast between the taciturn, even morose, aborigines
of S. America and the light-hearted, talkative negroes.  There is a nearly
similar contrast between the Malays and the Papuans (4.  Wallace, 'The
Malay Archipelago,' vol. ii. 1869, p. 178.), who live under the same
physical conditions, and are separated from each other only by a narrow
space of sea.

We will first consider the arguments which may be advanced in favour of
classing the races of man as distinct species, and then the arguments on
the other side.  If a naturalist, who had never before seen a Negro,
Hottentot, Australian, or Mongolian, were to compare them, he would at once
perceive that they differed in a multitude of characters, some of slight
and some of considerable importance.  On enquiry he would find that they
were adapted to live under widely different climates, and that they
differed somewhat in bodily constitution and mental disposition.  If he
were then told that hundreds of similar specimens could be brought from the
same countries, he would assuredly declare that they were as good species
as many to which he had been in the habit of affixing specific names.  This
conclusion would be greatly strengthened as soon as he had ascertained that
these forms had all retained the same character for many centuries; and
that negroes, apparently identical with existing negroes, had lived at
least 4000 years ago.  (5.  With respect to the figures in the famous
Egyptian caves of Abou-Simbel, M. Pouchet says ('The Plurality of the Human
Races,' Eng. translat., 1864, p. 50), that he was far from finding
recognisable representations of the dozen or more nations which some
authors believe that they can recognise.  Even some of the most strongly-
marked races cannot be identified with that degree of unanimity which might
have been expected from what has been written on the subject.  Thus Messrs.
Nott and Gliddon ('Types of Mankind,' p. 148), state that Rameses II., or
the Great, has features superbly European; whereas Knox, another firm
believer in the specific distinctness of the races of man ('Races of Man,'
1850, p. 201), speaking of young Memnon (the same as Rameses II., as I am
informed by Mr. Birch), insists in the strongest manner that he is
identical in character with the Jews of Antwerp.  Again, when I looked at
the statue of Amunoph III., I agreed with two officers of the
establishment, both competent judges, that he had a strongly-marked negro
type of features; but Messrs. Nott and Gliddon (ibid. p. 146, fig. 53),
describe him as a hybrid, but not of "negro intermixture.")  He would also
hear, on the authority of an excellent observer, Dr. Lund (6.  As quoted by
Nott and Gliddon, 'Types of Mankind,' 1854, p. 439.  They give also
corroborative evidence; but C. Vogt thinks that the subject requires
further investigation.), that the human skulls found in the caves of
Brazil, entombed with many extinct mammals, belonged to the same type as
that now prevailing throughout the American Continent.

Our naturalist would then perhaps turn to geographical distribution, and he
would probably declare that those forms must be distinct species, which
differ not only in appearance, but are fitted for hot, as well as damp or
dry countries, and for the Arctic regions.  He might appeal to the fact that
no species in the group next to man--namely, the Quadrumana, can resist a
low temperature, or any considerable change of climate; and that the
species which come nearest to man have never been reared to maturity, even
under the temperate climate of Europe.  He would be deeply impressed with
the fact, first noticed by Agassiz (7.  'Diversity of Origin of the Human
Races,' in the 'Christian Examiner,' July 1850.), that the different races
of man are distributed over the world in the same zoological provinces, as
those inhabited by undoubtedly distinct species and genera of mammals.
This is manifestly the case with the Australian, Mongolian, and Negro races
of man; in a less well-marked manner with the Hottentots; but plainly with
the Papuans and Malays, who are separated, as Mr. Wallace has shewn, by
nearly the same line which divides the great Malayan and Australian
zoological provinces.  The Aborigines of America range throughout the
Continent; and this at first appears opposed to the above rule, for most of
the productions of the Southern and Northern halves differ widely:  yet
some few living forms, as the opossum, range from the one into the other,
as did formerly some of the gigantic Edentata.  The Esquimaux, like other
Arctic animals, extend round the whole polar regions.  It should be
observed that the amount of difference between the mammals of the several
zoological provinces does not correspond with the degree of separation
between the latter; so that it can hardly be considered as an anomaly that
the Negro differs more, and the American much less from the other races of
man, than do the mammals of the African and American continents from the
mammals of the other provinces.  Man, it may be added, does not appear to
have aboriginally inhabited any oceanic island; and in this respect, he
resembles the other members of his class.

In determining whether the supposed varieties of the same kind of domestic
animal should be ranked as such, or as specifically distinct, that is,
whether any of them are descended from distinct wild species, every
naturalist would lay much stress on the fact of their external parasites
being specifically distinct.  All the more stress would be laid on this
fact, as it would be an exceptional one; for I am informed by Mr. Denny
that the most different kinds of dogs, fowls, and pigeons, in England, are
infested by the same species of Pediculi or lice.  Now Mr. A. Murray has
carefully examined the Pediculi collected in different countries from the
different races of man (8.  'Transactions of the Royal Society of
Edinburgh,' vol. xxii, 1861, p. 567.); and he finds that they differ, not
only in colour, but in the structure of their claws and limbs.  In every
case in which many specimens were obtained the differences were constant.
The surgeon of a whaling ship in the Pacific assured me that when the
Pediculi, with which some Sandwich Islanders on board swarmed, strayed on
to the bodies of the English sailors, they died in the course of three or
four days.  These Pediculi were darker coloured, and appeared different
from those proper to the natives of Chiloe in South America, of which he
gave me specimens.  These, again, appeared larger and much softer than
European lice.  Mr. Murray procured four kinds from Africa, namely, from
the Negroes of the Eastern and Western coasts, from the Hottentots and
Kaffirs; two kinds from the natives of Australia; two from North and two
from South America.  In these latter cases it may be presumed that the
Pediculi came from natives inhabiting different districts.  With insects
slight structural differences, if constant, are generally esteemed of
specific value:  and the fact of the races of man being infested by
parasites, which appear to be specifically distinct, might fairly be urged
as an argument that the races themselves ought to be classed as distinct
species.

Our supposed naturalist having proceeded thus far in his investigation,
would next enquire whether the races of men, when crossed, were in any
degree sterile.  He might consult the work (9.  'On the Phenomena of
Hybridity in the Genus Homo,' Eng. translat., 1864.) of Professor Broca, a
cautious and philosophical observer, and in this he would find good
evidence that some races were quite fertile together, but evidence of an
opposite nature in regard to other races.  Thus it has been asserted that
the native women of Australia and Tasmania rarely produce children to
European men; the evidence, however, on this head has now been shewn to be
almost valueless.  The half-castes are killed by the pure blacks:  and an
account has lately been published of eleven half-caste youths murdered and
burnt at the same time, whose remains were found by the police.  (10.  See
the interesting letter by Mr. T.A. Murray, in the 'Anthropological Review,'
April 1868, p. liii.  In this letter Count Strzelecki's statement that
Australian women who have borne children to a white man, are afterwards
sterile with their own race, is disproved.  M. A. de Quatrefages has also
collected (Revue des Cours Scientifiques, March, 1869, p. 239), much
evidence that Australians and Europeans are not sterile when crossed.)
Again, it has often been said that when mulattoes intermarry, they produce
few children; on the other hand, Dr. Bachman, of Charleston (11.  'An
Examination of Prof. Agassiz's Sketch of the Nat. Provinces of the Animal
World,' Charleston, 1855, p. 44.), positively asserts that he has known
mulatto families which have intermarried for several generations, and have
continued on an average as fertile as either pure whites or pure blacks.
Enquiries formerly made by Sir C. Lyell on this subject led him, as he
informs me, to the same conclusion.  (12.  Dr. Rohlfs writes to me that he
found the mixed races in the Great Sahara, derived from Arabs, Berbers, and
Negroes of three tribes, extraordinarily fertile.  On the other hand, Mr.
Winwood Reade informs me that the Negroes on the Gold Coast, though
admiring white men and mulattoes, have a maxim that mulattoes should not
intermarry, as the children are few and sickly.  This belief, as Mr. Reade
remarks, deserves attention, as white men have visited and resided on the
Gold Coast for four hundred years, so that the natives have had ample time
to gain knowledge through experience.)  In the United States the census for
the year 1854 included, according to Dr. Bachman, 405,751 mulattoes; and
this number, considering all the circumstances of the case, seems small;
but it may partly be accounted for by the degraded and anomalous position
of the class, and by the profligacy of the women.  A certain amount of
absorption of mulattoes into negroes must always be in progress; and this
would lead to an apparent diminution of the former.  The inferior vitality
of mulattoes is spoken of in a trustworthy work (13.  'Military and
Anthropological Statistics of American Soldiers,' by B.A. Gould, 1869, p.
319.) as a well-known phenomenon; and this, although a different
consideration from their lessened fertility, may perhaps be advanced as a
proof of the specific distinctness of the parent races.  No doubt both
animal and vegetable hybrids, when produced from extremely distinct
species, are liable to premature death; but the parents of mulattoes cannot
be put under the category of extremely distinct species.  The common Mule,
so notorious for long life and vigour, and yet so sterile, shews how little
necessary connection there is in hybrids between lessened fertility and
vitality; other analogous cases could be cited.

Even if it should hereafter be proved that all the races of men were
perfectly fertile together, he who was inclined from other reasons to rank
them as distinct species, might with justice argue that fertility and
sterility are not safe criterions of specific distinctness.  We know that
these qualities are easily affected by changed conditions of life, or by
close inter-breeding, and that they are governed by highly complex laws,
for instance, that of the unequal fertility of converse crosses between the
same two species.  With forms which must be ranked as undoubted species, a
perfect series exists from those which are absolutely sterile when crossed,
to those which are almost or completely fertile.  The degrees of sterility
do not coincide strictly with the degrees of difference between the parents
in external structure or habits of life.  Man in many respects may be
compared with those animals which have long been domesticated, and a large
body of evidence can be advanced in favour of the Pallasian doctrine (14.
The 'Variation of Animals and Plants under Domestication,' vol. ii. p. 109.
I may here remind the reader that the sterility of species when crossed is
not a specially-acquired quality, but, like the incapacity of certain trees
to be grafted together, is incidental on other acquired differences.  The
nature of these differences is unknown, but they relate more especially to
the reproductive system, and much less so to external structure or to
ordinary differences in constitution.  One important element in the
sterility of crossed species apparently lies in one or both having been
long habituated to fixed conditions; for we know that changed conditions
have a special influence on the reproductive system, and we have good
reason to believe (as before remarked) that the fluctuating conditions of
domestication tend to eliminate that sterility which is so general with
species, in a natural state, when crossed.  It has elsewhere been shewn by
me (ibid. vol. ii. p. 185, and 'Origin of Species,' 5th edit. p. 317), that
the sterility of crossed species has not been acquired through natural
selection:  we can see that when two forms have already been rendered very
sterile, it is scarcely possible that their sterility should be augmented
by the preservation or survival of the more and more sterile individuals;
for, as the sterility increases, fewer and fewer offspring will be produced
from which to breed, and at last only single individuals will be produced
at the rarest intervals.  But there is even a higher grade of sterility
than this.  Both Gartner and Kolreuter have proved that in genera of
plants, including many species, a series can be formed from species which,
when crossed, yield fewer and fewer seeds, to species which never produce a
single seed, but yet are affected by the pollen of the other species, as
shewn by the swelling of the germen.  It is here manifestly impossible to
select the more sterile individuals, which have already ceased to yield
seeds; so that the acme of sterility, when the germen alone is affected,
cannot have been gained through selection.  This acme, and no doubt the
other grades of sterility, are the incidental results of certain unknown
differences in the constitution of the reproductive system of the species
which are crossed.), that domestication tends to eliminate the sterility
which is so general a result of the crossing of species in a state of
nature.  From these several considerations, it may be justly urged that the
perfect fertility of the intercrossed races of man, if established, would
not absolutely preclude us from ranking them as distinct species.

Independently of fertility, the characters presented by the offspring from
a cross have been thought to indicate whether or not the parent-forms ought
to be ranked as species or varieties; but after carefully studying the
evidence, I have come to the conclusion that no general rules of this kind
can be trusted.  The ordinary result of a cross is the production of a
blended or intermediate form; but in certain cases some of the offspring
take closely after one parent-form, and some after the other.  This is
especially apt to occur when the parents differ in characters which first
appeared as sudden variations or monstrosities.  (15.  'The Variation of
Animals,' etc., vol. ii. p. 92.)  I refer to this point, because Dr. Rohlfs
informs me that he has frequently seen in Africa the offspring of negroes
crossed with members of other races, either completely black or completely
white, or rarely piebald.  On the other hand, it is notorious that in
America mulattoes commonly present an intermediate appearance.

We have now seen that a naturalist might feel himself fully justified in
ranking the races of man as distinct species; for he has found that they
are distinguished by many differences in structure and constitution, some
being of importance.  These differences have, also, remained nearly
constant for very long periods of time.  Our naturalist will have been in
some degree influenced by the enormous range of man, which is a great
anomaly in the class of mammals, if mankind be viewed as a single species.
He will have been struck with the distribution of the several so-called
races, which accords with that of other undoubtedly distinct species of
mammals.  Finally, he might urge that the mutual fertility of all the races
has not as yet been fully proved, and even if proved would not be an
absolute proof of their specific identity.

On the other side of the question, if our supposed naturalist were to
enquire whether the forms of man keep distinct like ordinary species, when
mingled together in large numbers in the same country, he would immediately
discover that this was by no means the case.  In Brazil he would behold an
immense mongrel population of Negroes and Portuguese; in Chiloe, and other
parts of South America, he would behold the whole population consisting of
Indians and Spaniards blended in various degrees.  (16.  M. de Quatrefages
has given ('Anthropological Review,' Jan. 1869, p. 22), an interesting
account of the success and energy of the Paulistas in Brazil, who are a
much crossed race of Portuguese and Indians, with a mixture of the blood of
other races.)  In many parts of the same continent he would meet with the
most complex crosses between Negroes, Indians, and Europeans; and judging
from the vegetable kingdom, such triple crosses afford the severest test of
the mutual fertility of the parent forms.  In one island of the Pacific he
would find a small population of mingled Polynesian and English blood; and
in the Fiji Archipelago a population of Polynesian and Negritos crossed in
all degrees.  Many analogous cases could be added; for instance, in Africa.
Hence the races of man are not sufficiently distinct to inhabit the same
country without fusion; and the absence of fusion affords the usual and
best test of specific distinctness.

Our naturalist would likewise be much disturbed as soon as he perceived
that the distinctive characters of all the races were highly variable.
This fact strikes every one on first beholding the negro slaves in Brazil,
who have been imported from all parts of Africa.  The same remark holds
good with the Polynesians, and with many other races.  It may be doubted
whether any character can be named which is distinctive of a race and is
constant.  Savages, even within the limits of the same tribe, are not
nearly so uniform in character, as has been often asserted.  Hottentot
women offer certain peculiarities, more strongly marked than those
occurring in any other race, but these are known not to be of constant
occurrence.  In the several American tribes, colour and hairiness differ
considerably; as does colour to a certain degree, and the shape of the
features greatly, in the Negroes of Africa.  The shape of the skull varies
much in some races (17.  For instance, with the aborigines of America and
Australia, Prof. Huxley says ('Transact. Internat. Congress of Prehist.
Arch.' 1868, p. 105), that the skulls of many South Germans and Swiss are
"as short and as broad as those of the Tartars," etc.); and so it is with
every other character.  Now all naturalists have learnt by dearly bought
experience, how rash it is to attempt to define species by the aid of
inconstant characters.

But the most weighty of all the arguments against treating the races of man
as distinct species, is that they graduate into each other, independently
in many cases, as far as we can judge, of their having intercrossed.  Man
has been studied more carefully than any other animal, and yet there is the
greatest possible diversity amongst capable judges whether he should be
classed as a single species or race, or as two (Virey), as three
(Jacquinot), as four (Kant), five (Blumenbach), six (Buffon), seven
(Hunter), eight (Agassiz), eleven (Pickering), fifteen (Bory St. Vincent),
sixteen (Desmoulins), twenty-two (Morton), sixty (Crawfurd), or as sixty-
three, according to Burke.  (18.  See a good discussion on this subject in
Waitz, 'Introduction to Anthropology,' Eng. translat., 1863, pp. 198-208,
227.  I have taken some of the above statements from H. Tuttle's 'Origin
and Antiquity of Physical Man,' Boston, 1866, p. 35.)  This diversity of
judgment does not prove that the races ought not to be ranked as species,
but it shews that they graduate into each other, and that it is hardly
possible to discover clear distinctive characters between them.

Every naturalist who has had the misfortune to undertake the description of
a group of highly varying organisms, has encountered cases (I speak after
experience) precisely like that of man; and if of a cautious disposition,
he will end by uniting all the forms which graduate into each other, under
a single species; for he will say to himself that he has no right to give
names to objects which he cannot define.  Cases of this kind occur in the
Order which includes man, namely in certain genera of monkeys; whilst in
other genera, as in Cercopithecus, most of the species can be determined
with certainty.  In the American genus Cebus, the various forms are ranked
by some naturalists as species, by others as mere geographical races.  Now
if numerous specimens of Cebus were collected from all parts of South
America, and those forms which at present appear to be specifically
distinct, were found to graduate into each other by close steps, they would
usually be ranked as mere varieties or races; and this course has been
followed by most naturalists with respect to the races of man.
Nevertheless, it must be confessed that there are forms, at least in the
vegetable kingdom (19.  Prof. Nageli has carefully described several
striking cases in his 'Botanische Mittheilungen,' B. ii. 1866, ss. 294-369.
Prof. Asa Gray has made analogous remarks on some intermediate forms in the
Compositae of N. America.), which we cannot avoid naming as species, but
which are connected together by numberless gradations, independently of
intercrossing.

Some naturalists have lately employed the term "sub-species" to designate
forms which possess many of the characteristics of true species, but which
hardly deserve so high a rank.  Now if we reflect on the weighty arguments
above given, for raising the races of man to the dignity of species, and
the insuperable difficulties on the other side in defining them, it seems
that the term "sub-species" might here be used with propriety.  But from
long habit the term "race" will perhaps always be employed.  The choice of
terms is only so far important in that it is desirable to use, as far as
possible, the same terms for the same degrees of difference.  Unfortunately
this can rarely be done:  for the larger genera generally include closely-
allied forms, which can be distinguished only with much difficulty, whilst
the smaller genera within the same family include forms that are perfectly
distinct; yet all must be ranked equally as species.  So again, species
within the same large genus by no means resemble each other to the same
degree:  on the contrary, some of them can generally be arranged in little
groups round other species, like satellites round planets.  (20.  'Origin
of Species,' 5th edit. p. 68.)

The question whether mankind consists of one or several species has of late
years been much discussed by anthropologists, who are divided into the two
schools of monogenists and polygenists.  Those who do not admit the
principle of evolution, must look at species as separate creations, or in
some manner as distinct entities; and they must decide what forms of man
they will consider as species by the analogy of the method commonly pursued
in ranking other organic beings as species.  But it is a hopeless endeavour
to decide this point, until some definition of the term "species" is
generally accepted; and the definition must not include an indeterminate
element such as an act of creation.  We might as well attempt without any
definition to decide whether a certain number of houses should be called a
village, town, or city.  We have a practical illustration of the difficulty
in the never-ending doubts whether many closely-allied mammals, birds,
insects, and plants, which represent each other respectively in North
America and Europe, should be ranked as species or geographical races; and
the like holds true of the productions of many islands situated at some
little distance from the nearest continent.

Those naturalists, on the other hand, who admit the principle of evolution,
and this is now admitted by the majority of rising men, will feel no doubt
that all the races of man are descended from a single primitive stock;
whether or not they may think fit to designate the races as distinct
species, for the sake of expressing their amount of difference.  (21.  See
Prof. Huxley to this effect in the 'Fortnightly Review,' 1865, p. 275.)
With our domestic animals the question whether the various races have
arisen from one or more species is somewhat different.  Although it may be
admitted that all the races, as well as all the natural species within the
same genus, have sprung from the same primitive stock, yet it is a fit
subject for discussion, whether all the domestic races of the dog, for
instance, have acquired their present amount of difference since some one
species was first domesticated by man; or whether they owe some of their
characters to inheritance from distinct species, which had already been
differentiated in a state of nature.  With man no such question can arise,
for he cannot be said to have been domesticated at any particular period.

During an early stage in the divergence of the races of man from a common
stock, the differences between the races and their number must have been
small; consequently as far as their distinguishing characters are
concerned, they then had less claim to rank as distinct species than the
existing so-called races.  Nevertheless, so arbitrary is the term of
species, that such early races would perhaps have been ranked by some
naturalists as distinct species, if their differences, although extremely
slight, had been more constant than they are at present, and had not
graduated into each other.

It is however possible, though far from probable, that the early
progenitors of man might formerly have diverged much in character, until
they became more unlike each other than any now existing races; but that
subsequently, as suggested by Vogt (22.  'Lectures on Man,' Eng. translat.,
1864, p. 468.), they converged in character.  When man selects the
offspring of two distinct species for the same object, he sometimes induces
a considerable amount of convergence, as far as general appearance is
concerned.  This is the case, as shewn by von Nathusius (23.  'Die Rassen
des Schweines,' 1860, s. 46.  'Vorstudien fuer Geschichte,' etc.,
Schweinesschaedel, 1864, s. 104.  With respect to cattle, see M. de
Quatrefages, 'Unite de l'Espece Humaine,' 1861, p. 119.), with the improved
breeds of the pig, which are descended from two distinct species; and in a
less marked manner with the improved breeds of cattle.  A great anatomist,
Gratiolet, maintains that the anthropomorphous apes do not form a natural
sub-group; but that the orang is a highly developed gibbon or
semnopithecus, the chimpanzee a highly developed macacus, and the gorilla a
highly developed mandrill.  If this conclusion, which rests almost
exclusively on brain-characters, be admitted, we should have a case of
convergence at least in external characters, for the anthropomorphous apes
are certainly more like each other in many points, than they are to other
apes.  All analogical resemblances, as of a whale to a fish, may indeed be
said to be cases of convergence; but this term has never been applied to
superficial and adaptive resemblances.  It would, however, be extremely
rash to attribute to convergence close similarity of character in many
points of structure amongst the modified descendants of widely distinct
beings.  The form of a crystal is determined solely by the molecular
forces, and it is not surprising that dissimilar substances should
sometimes assume the same form; but with organic beings we should bear in
mind that the form of each depends on an infinity of complex relations,
namely on variations, due to causes far too intricate to be followed,--on
the nature of the variations preserved, these depending on the physical
conditions, and still more on the surrounding organisms which compete with
each,--and lastly, on inheritance (in itself a fluctuating element) from
innumerable progenitors, all of which have had their forms determined
through equally complex relations.  It appears incredible that the modified
descendants of two organisms, if these differed from each other in a marked
manner, should ever afterwards converge so closely as to lead to a near
approach to identity throughout their whole organisation.  In the case of
the convergent races of pigs above referred to, evidence of their descent
from two primitive stocks is, according to von Nathusius, still plainly
retained, in certain bones of their skulls.  If the races of man had
descended, as is supposed by some naturalists, from two or more species,
which differed from each other as much, or nearly as much, as does the
orang from the gorilla, it can hardly be doubted that marked differences in
the structure of certain bones would still be discoverable in man as he now
exists.

Although the existing races of man differ in many respects, as in colour,
hair, shape of skull, proportions of the body, etc., yet if their whole
structure be taken into consideration they are found to resemble each other
closely in a multitude of points.  Many of these are of so unimportant or
of so singular a nature, that it is extremely improbable that they should
have been independently acquired by aboriginally distinct species or races.
The same remark holds good with equal or greater force with respect to the
numerous points of mental similarity between the most distinct races of
man.  The American aborigines, Negroes and Europeans are as different from
each other in mind as any three races that can be named; yet I was
incessantly struck, whilst living with the Fuegians on board the "Beagle,"
with the many little traits of character, shewing how similar their minds
were to ours; and so it was with a full-blooded negro with whom I happened
once to be intimate.

He who will read Mr. Tylor's and Sir J. Lubbock's interesting works (24.
Tylor's 'Early History of Mankind,' 1865:  with respect to gesture-
language, see p. 54.  Lubbock's 'Prehistoric Times,' 2nd edit. 1869.) can
hardly fail to be deeply impressed with the close similarity between the
men of all races in tastes, dispositions and habits.  This is shewn by the
pleasure which they all take in dancing, rude music, acting, painting,
tattooing, and otherwise decorating themselves; in their mutual
comprehension of gesture-language, by the same expression in their
features, and by the same inarticulate cries, when excited by the same
emotions.  This similarity, or rather identity, is striking, when
contrasted with the different expressions and cries made by distinct
species of monkeys.  There is good evidence that the art of shooting with
bows and arrows has not been handed down from any common progenitor of
mankind, yet as Westropp and Nilsson have remarked (25.  'On Analogous
Forms of Implements,' in 'Memoirs of Anthropological Society' by H.M.
Westropp.  'The Primitive Inhabitants of Scandinavia,' Eng. translat.,
edited by Sir J. Lubbock, 1868, p. 104.), the stone arrow-heads, brought
from the most distant parts of the world, and manufactured at the most
remote periods, are almost identical; and this fact can only be accounted
for by the various races having similar inventive or mental powers.  The
same observation has been made by archaeologists (26.  Westropp 'On
Cromlechs,' etc., 'Journal of Ethnological Soc.' as given in 'Scientific
Opinion,' June 2nd, 1869, p. 3.) with respect to certain widely-prevalent
ornaments, such as zig-zags, etc.; and with respect to various simple
beliefs and customs, such as the burying of the dead under megalithic
structures.  I remember observing in South America (27.  'Journal of
Researches:  Voyage of the "Beagle,"' p. 46.), that there, as in so many
other parts of the world, men have generally chosen the summits of lofty
hills, to throw up piles of stones, either as a record of some remarkable
event, or for burying their dead.

Now when naturalists observe a close agreement in numerous small details of
habits, tastes, and dispositions between two or more domestic races, or
between nearly-allied natural forms, they use this fact as an argument that
they are descended from a common progenitor who was thus endowed; and
consequently that all should be classed under the same species.  The same
argument may be applied with much force to the races of man.

As it is improbable that the numerous and unimportant points of resemblance
between the several races of man in bodily structure and mental faculties
(I do not here refer to similar customs) should all have been independently
acquired, they must have been inherited from progenitors who had these same
characters.  We thus gain some insight into the early state of man, before
he had spread step by step over the face of the earth.  The spreading of
man to regions widely separated by the sea, no doubt, preceded any great
amount of divergence of character in the several races; for otherwise we
should sometimes meet with the same race in distinct continents; and this
is never the case.  Sir J. Lubbock, after comparing the arts now practised
by savages in all parts of the world, specifies those which man could not
have known, when he first wandered from his original birthplace; for if
once learnt they would never have been forgotten.  (28.  'Prehistoric
Times,' 1869, p. 574.)  He thus shews that "the spear, which is but a
development of the knife-point, and the club, which is but a long hammer,
are the only things left."  He admits, however, that the art of making fire
probably had been already discovered, for it is common to all the races now
existing, and was known to the ancient cave-inhabitants of Europe.  Perhaps
the art of making rude canoes or rafts was likewise known; but as man
existed at a remote epoch, when the land in many places stood at a very
different level to what it does now, he would have been able, without the
aid of canoes, to have spread widely.  Sir J. Lubbock further remarks how
improbable it is that our earliest ancestors could have "counted as high as
ten, considering that so many races now in existence cannot get beyond
four."  Nevertheless, at this early period, the intellectual and social
faculties of man could hardly have been inferior in any extreme degree to
those possessed at present by the lowest savages; otherwise primeval man
could not have been so eminently successful in the struggle for life, as
proved by his early and wide diffusion.

From the fundamental differences between certain languages, some
philologists have inferred that when man first became widely diffused, he
was not a speaking animal; but it may be suspected that languages, far less
perfect than any now spoken, aided by gestures, might have been used, and
yet have left no traces on subsequent and more highly-developed tongues.
Without the use of some language, however imperfect, it appears doubtful
whether man's intellect could have risen to the standard implied by his
dominant position at an early period.

Whether primeval man, when he possessed but few arts, and those of the
rudest kind, and when his power of language was extremely imperfect, would
have deserved to be called man, must depend on the definition which we
employ.  In a series of forms graduating insensibly from some ape-like
creature to man as he now exists, it would be impossible to fix on any
definite point where the term "man" ought to be used.  But this is a matter
of very little importance.  So again, it is almost a matter of indifference
whether the so-called races of man are thus designated, or are ranked as
species or sub-species; but the latter term appears the more appropriate.
Finally, we may conclude that when the principle of evolution is generally
accepted, as it surely will be before long, the dispute between the
monogenists and the polygenists will die a silent and unobserved death.

One other question ought not to be passed over without notice, namely,
whether, as is sometimes assumed, each sub-species or race of man has
sprung from a single pair of progenitors.  With our domestic animals a new
race can readily be formed by carefully matching the varying offspring from
a single pair, or even from a single individual possessing some new
character; but most of our races have been formed, not intentionally from a
selected pair, but unconsciously by the preservation of many individuals
which have varied, however slightly, in some useful or desired manner.  If
in one country stronger and heavier horses, and in another country lighter
and fleeter ones, were habitually preferred, we may feel sure that two
distinct sub-breeds would be produced in the course of time, without any
one pair having been separated and bred from, in either country.  Many
races have been thus formed, and their manner of formation is closely
analogous to that of natural species.  We know, also, that the horses taken
to the Falkland Islands have, during successive generations, become smaller
and weaker, whilst those which have run wild on the Pampas have acquired
larger and coarser heads; and such changes are manifestly due, not to any
one pair, but to all the individuals having been subjected to the same
conditions, aided, perhaps, by the principle of reversion.  The new sub-
breeds in such cases are not descended from any single pair, but from many
individuals which have varied in different degrees, but in the same general
manner; and we may conclude that the races of man have been similarly
produced, the modifications being either the direct result of exposure to
different conditions, or the indirect result of some form of selection.
But to this latter subject we shall presently return.

ON THE EXTINCTION OF THE RACES OF MAN.

The partial or complete extinction of many races and sub-races of man is
historically known.  Humboldt saw in South America a parrot which was the
sole living creature that could speak a word of the language of a lost
tribe.  Ancient monuments and stone implements found in all parts of the
world, about which no tradition has been preserved by the present
inhabitants, indicate much extinction.  Some small and broken tribes,
remnants of former races, still survive in isolated and generally
mountainous districts.  In Europe the ancient races were all, according to
Shaaffhausen (29.  Translation in 'Anthropological Review,' Oct. 1868, p.
431.), "lower in the scale than the rudest living savages"; they must
therefore have differed, to a certain extent, from any existing race.  The
remains described by Professor Broca from Les Eyzies, though they
unfortunately appear to have belonged to a single family, indicate a race
with a most singular combination of low or simious, and of high
characteristics.  This race is "entirely different from any other, ancient
or modern, that we have heard of."  (30.  'Transactions, International
Congress of Prehistoric Archaeology' 1868, pp. 172-175.  See also Broca
(tr.) in 'Anthropological Review,' Oct. 1868, p. 410.)  It differed,
therefore, from the quaternary race of the caverns of Belgium.

Man can long resist conditions which appear extremely unfavourable for his
existence.  (31.  Dr. Gerland, 'Ueber das Aussterben der Naturvoelker,'
1868, s. 82.)  He has long lived in the extreme regions of the North, with
no wood for his canoes or implements, and with only blubber as fuel, and
melted snow as drink.  In the southern extremity of America the Fuegians
survive without the protection of clothes, or of any building worthy to be
called a hovel.  In South Africa the aborigines wander over arid plains,
where dangerous beasts abound.  Man can withstand the deadly influence of
the Terai at the foot of the Himalaya, and the pestilential shores of
tropical Africa.

Extinction follows chiefly from the competition of tribe with tribe, and
race with race.  Various checks are always in action, serving to keep down
the numbers of each savage tribe,--such as periodical famines, nomadic
habits and the consequent deaths of infants, prolonged suckling, wars,
accidents, sickness, licentiousness, the stealing of women, infanticide,
and especially lessened fertility.  If any one of these checks increases in
power, even slightly, the tribe thus affected tends to decrease; and when
of two adjoining tribes one becomes less numerous and less powerful than
the other, the contest is soon settled by war, slaughter, cannibalism,
slavery, and absorption.  Even when a weaker tribe is not thus abruptly
swept away, if it once begins to decrease, it generally goes on decreasing
until it becomes extinct.  (32.  Gerland (ibid. s. 12) gives facts in
support of this statement.)

When civilised nations come into contact with barbarians the struggle is
short, except where a deadly climate gives its aid to the native race.  Of
the causes which lead to the victory of civilised nations, some are plain
and simple, others complex and obscure.  We can see that the cultivation of
the land will be fatal in many ways to savages, for they cannot, or will
not, change their habits.  New diseases and vices have in some cases proved
highly destructive; and it appears that a new disease often causes much
death, until those who are most susceptible to its destructive influence
are gradually weeded out (33.  See remarks to this effect in Sir H.
Holland's 'Medical Notes and Reflections,' 1839, p. 390.); and so it may be
with the evil effects from spirituous liquors, as well as with the
unconquerably strong taste for them shewn by so many savages.  It further
appears, mysterious as is the fact, that the first meeting of distinct and
separated people generates disease.  (34.  I have collected ('Journal of
Researches:  Voyage of the "Beagle,"' p. 435) a good many cases bearing on
this subject; see also Gerland, ibid. s. 8.  Poeppig speaks of the "breath
of civilisation as poisonous to savages.")  Mr. Sproat, who in Vancouver
Island closely attended to the subject of extinction, believed that changed
habits of life, consequent on the advent of Europeans, induces much ill
health.  He lays, also, great stress on the apparently trifling cause that
the natives become "bewildered and dull by the new life around them; they
lose the motives for exertion, and get no new ones in their place."  (35.
Sproat, 'Scenes and Studies of Savage Life,' 1868, p. 284.)

The grade of their civilisation seems to be a most important element in the
success of competing nations.  A few centuries ago Europe feared the
inroads of Eastern barbarians; now any such fear would be ridiculous.  It
is a more curious fact, as Mr. Bagehot has remarked, that savages did not
formerly waste away before the classical nations, as they now do before
modern civilised nations; had they done so, the old moralists would have
mused over the event; but there is no lament in any writer of that period
over the perishing barbarians.  (36.  Bagehot, 'Physics and Politics,'
'Fortnightly Review,' April 1, 1868, p. 455.)  The most potent of all the
causes of extinction, appears in many cases to be lessened fertility and
ill-health, especially amongst the children, arising from changed
conditions of life, notwithstanding that the new conditions may not be
injurious in themselves.  I am much indebted to Mr. H.H. Howorth for having
called my attention to this subject, and for having given me information
respecting it.  I have collected the following cases.

When Tasmania was first colonised the natives were roughly estimated by
some at 7000 and by others at 20,000.  Their number was soon greatly
reduced, chiefly by fighting with the English and with each other.  After
the famous hunt by all the colonists, when the remaining natives delivered
themselves up to the government, they consisted only of 120 individuals
(37.  All the statements here given are taken from 'The Last of the
Tasmanians,' by J. Bonwick, 1870.), who were in 1832 transported to
Flinders Island.  This island, situated between Tasmania and Australia, is
forty miles long, and from twelve to eighteen miles broad:  it seems
healthy, and the natives were well treated.  Nevertheless, they suffered
greatly in health.  In 1834 they consisted (Bonwick, p. 250) of forty-seven
adult males, forty-eight adult females, and sixteen children, or in all of
111 souls.  In 1835 only one hundred were left.  As they continued rapidly
to decrease, and as they themselves thought that they should not perish so
quickly elsewhere, they were removed in 1847 to Oyster Cove in the southern
part of Tasmania.  They then consisted (Dec. 20th, 1847) of fourteen men,
twenty-two women and ten children.  (38.  This is the statement of the
Governor of Tasmania, Sir W. Denison, 'Varieties of Vice-Regal Life,' 1870,
vol. i. p. 67.)  But the change of site did no good.  Disease and death
still pursued them, and in 1864 one man (who died in 1869), and three
elderly women alone survived.  The infertility of the women is even a more
remarkable fact than the liability of all to ill-health and death.  At the
time when only nine women were left at Oyster Cove, they told Mr. Bonwick
(p. 386), that only two had ever borne children:  and these two had
together produced only three children!

With respect to the cause of this extraordinary state of things, Dr. Story
remarks that death followed the attempts to civilise the natives.  "If left
to themselves to roam as they were wont and undisturbed, they would have
reared more children, and there would have been less mortality."  Another
careful observer of the natives, Mr. Davis, remarks, "The births have been
few and the deaths numerous.  This may have been in a great measure owing
to their change of living and food; but more so to their banishment from
the mainland of Van Diemen's Land, and consequent depression of spirits"
(Bonwick, pp. 388, 390).

Similar facts have been observed in two widely different parts of
Australia.  The celebrated explorer, Mr. Gregory, told Mr. Bonwick, that in
Queensland "the want of reproduction was being already felt with the
blacks, even in the most recently settled parts, and that decay would set
in."  Of thirteen aborigines from Shark's Bay who visited Murchison River,
twelve died of consumption within three months.  (39.  For these cases, see
Bonwick's 'Daily Life of the Tasmanians,' 1870, p. 90:  and the 'Last of
the Tasmanians,' 1870, p. 386.)

The decrease of the Maories of New Zealand has been carefully investigated
by Mr. Fenton, in an admirable Report, from which all the following
statements, with one exception, are taken.  (40.  'Observations on the
Aboriginal Inhabitants of New Zealand,' published by the Government, 1859.)
The decrease in number since 1830 is admitted by every one, including the
natives themselves, and is still steadily progressing.  Although it has
hitherto been found impossible to take an actual census of the natives,
their numbers were carefully estimated by residents in many districts.  The
result seems trustworthy, and shows that during the fourteen years,
previous to 1858, the decrease was 19.42 per cent.  Some of the tribes,
thus carefully examined, lived above a hundred miles apart, some on the
coast, some inland; and their means of subsistence and habits differed to a
certain extent (p. 28).  The total number in 1858 was believed to be
53,700, and in 1872, after a second interval of fourteen years, another
census was taken, and the number is given as only 36,359, shewing a
decrease of 32.29 per cent!  (41.  'New Zealand,' by Alex. Kennedy, 1873,
p. 47.)  Mr. Fenton, after shewing in detail the insufficiency of the
various causes, usually assigned in explanation of this extraordinary
decrease, such as new diseases, the profligacy of the women, drunkenness,
wars, etc., concludes on weighty grounds that it depends chiefly on the
unproductiveness of the women, and on the extraordinary mortality of the
young children (pp. 31, 34).  In proof of this he shews (p. 33) that in
1844 there was one non-adult for every 2.57 adults; whereas in 1858 there
was only one non-adult for every 3.27 adults.  The mortality of the adults
is also great.  He adduces as a further cause of the decrease the
inequality of the sexes; for fewer females are born than males.  To this
latter point, depending perhaps on a widely distinct cause, I shall return
in a future chapter.  Mr. Fenton contrasts with astonishment the decrease
in New Zealand with the increase in Ireland; countries not very dissimilar
in climate, and where the inhabitants now follow nearly similar habits.
The Maories themselves (p. 35) "attribute their decadence, in some measure,
to the introduction of new food and clothing, and the attendant change of
habits"; and it will be seen, when we consider the influence of changed
conditions on fertility, that they are probably right.  The diminution
began between the years 1830 and 1840; and Mr. Fenton shews (p. 40) that
about 1830, the art of manufacturing putrid corn (maize), by long steeping
in water, was discovered and largely practised; and this proves that a
change of habits was beginning amongst the natives, even when New Zealand
was only thinly inhabited by Europeans.  When I visited the Bay of Islands
in 1835, the dress and food of the inhabitants had already been much
modified:  they raised potatoes, maize, and other agricultural produce, and
exchanged them for English manufactured goods and tobacco.

It is evident from many statements in the life of Bishop Patteson (42.
'Life of J.C. Patteson,' by C.M. Younge, 1874; see more especially vol. i.
p. 530.), that the Melanesians of the New Hebrides and neighbouring
archipelagoes, suffered to an extraordinary degree in health, and perished
in large numbers, when they were removed to New Zealand, Norfolk Island,
and other salubrious places, in order to be educated as missionaries.

The decrease of the native population of the Sandwich Islands is as
notorious as that of New Zealand.  It has been roughly estimated by those
best capable of judging, that when Cook discovered the Islands in 1779, the
population amounted to about 300,000.  According to a loose census in 1823,
the numbers then were 142,050.  In 1832, and at several subsequent periods,
an accurate census was officially taken, but I have been able to obtain
only the following returns:
                Native Population          Annual rate of decrease
                                           per cent., assuming it to
              (Except during 1832 and      have been uniform between
              1836, when the few           the successive censuses;
              foreigners in the islands    these censuses being taken
  Year        were included.)              at irregular intervals.

  1832              130,313
                                                   4.46
  1836              108,579
                                                   2.47
  1853               71,019
                                                   0.81
  1860               67,084
                                                   2.18
  1866               58,765
                                                   2.17
  1872               51,531

We here see that in the interval of forty years, between 1832 and 1872, the
population has decreased no less than sixty-eight per cent.!  This has been
attributed by most writers to the profligacy of the women, to former bloody
wars, and to the severe labour imposed on conquered tribes and to newly
introduced diseases, which have been on several occasions extremely
destructive.  No doubt these and other such causes have been highly
efficient, and may account for the extraordinary rate of decrease between
the years 1832 and 1836; but the most potent of all the causes seems to be
lessened fertility.  According to Dr. Ruschenberger of the U.S. Navy, who
visited these islands between 1835 and 1837, in one district of Hawaii,
only twenty-five men out of 1134, and in another district only ten out of
637, had a family with as many as three children.  Of eighty married women,
only thirty-nine had ever borne children; and "the official report gives an
average of half a child to each married couple in the whole island."  This
is almost exactly the same average as with the Tasmanians at Oyster Cove.
Jarves, who published his History in 1843, says that "families who have
three children are freed from all taxes; those having more, are rewarded by
gifts of land and other encouragements."  This unparalleled enactment by
the government well shews how infertile the race had become.  The Rev. A.
Bishop stated in the Hawaiian 'Spectator' in 1839, that a large proportion
of the children die at early ages, and Bishop Staley informs me that this
is still the case, just as in New Zealand.  This has been attributed to the
neglect of the children by the women, but it is probably in large part due
to innate weakness of constitution in the children, in relation to the
lessened fertility of their parents.  There is, moreover, a further
resemblance to the case of New Zealand, in the fact that there is a large
excess of male over female births:  the census of 1872 gives 31,650 males
to 25,247 females of all ages, that is 125.36 males for every 100 females;
whereas in all civilised countries the females exceed the males.  No doubt
the profligacy of the women may in part account for their small fertility;
but their changed habits of life is a much more probable cause, and which
will at the same time account for the increased mortality, especially of
the children.  The islands were visited by Cook in 1779, Vancouver in 1794,
and often subsequently by whalers.  In 1819 missionaries arrived, and found
that idolatry had been already abolished, and other changes effected by the
king.  After this period there was a rapid change in almost all the habits
of life of the natives, and they soon became "the most civilised of the
Pacific Islanders."  One of my informants, Mr. Coan, who was born on the
islands, remarks that the natives have undergone a greater change in their
habits of life in the course of fifty years than Englishmen during a
thousand years.  From information received from Bishop Staley, it does not
appear that the poorer classes have ever much changed their diet, although
many new kinds of fruit have been introduced, and the sugar-cane is in
universal use.  Owing, however, to their passion for imitating Europeans,
they altered their manner of dressing at an early period, and the use of
alcoholic drinks became very general.  Although these changes appear
inconsiderable, I can well believe, from what is known with respect to
animals, that they might suffice to lessen the fertility of the natives.
(43.  The foregoing statements are taken chiefly from the following works:
Jarves' 'History of the Hawaiian Islands,' 1843, pp. 400-407.  Cheever,
'Life in the Sandwich Islands,' 1851, p. 277.  Ruschenberger is quoted by
Bonwick, 'Last of the Tasmanians,' 1870, p. 378.  Bishop is quoted by Sir
E. Belcher, 'Voyage Round the World,' 1843, vol. i. p. 272.  I owe the
census of the several years to the kindness of Mr. Coan, at the request of
Dr. Youmans of New York; and in most cases I have compared the Youmans
figures with those given in several of the above-named works.  I have
omitted the census for 1850, as I have seen two widely different numbers
given.)

Lastly, Mr. Macnamara states (44.  'The Indian Medical Gazette,' Nov. 1,
1871, p. 240.) that the low and degraded inhabitants of the Andaman
Islands, on the eastern side of the Gulf of Bengal, are "eminently
susceptible to any change of climate:  in fact, take them away from their
island homes, and they are almost certain to die, and that independently of
diet or extraneous influences."  He further states that the inhabitants of
the Valley of Nepal, which is extremely hot in summer, and also the various
hill-tribes of India, suffer from dysentery and fever when on the plains;
and they die if they attempt to pass the whole year there.

We thus see that many of the wilder races of man are apt to suffer much in
health when subjected to changed conditions or habits of life, and not
exclusively from being transported to a new climate.  Mere alterations in
habits, which do not appear injurious in themselves, seem to have this same
effect; and in several cases the children are particularly liable to
suffer.  It has often been said, as Mr. Macnamara remarks, that man can
resist with impunity the greatest diversities of climate and other changes;
but this is true only of the civilised races.  Man in his wild condition
seems to be in this respect almost as susceptible as his nearest allies,
the anthropoid apes, which have never yet survived long, when removed from
their native country.

Lessened fertility from changed conditions, as in the case of the
Tasmanians, Maories, Sandwich Islanders, and apparently the Australians, is
still more interesting than their liability to ill-health and death; for
even a slight degree of infertility, combined with those other causes which
tend to check the increase of every population, would sooner or later lead
to extinction.  The diminution of fertility may be explained in some cases
by the profligacy of the women (as until lately with the Tahitians), but
Mr. Fenton has shewn that this explanation by no means suffices with the
New Zealanders, nor does it with the Tasmanians.

In the paper above quoted, Mr. Macnamara gives reasons for believing that
the inhabitants of districts subject to malaria are apt to be sterile; but
this cannot apply in several of the above cases.  Some writers have
suggested that the aborigines of islands have suffered in fertility and
health from long continued inter-breeding; but in the above cases
infertility has coincided too closely with the arrival of Europeans for us
to admit this explanation.  Nor have we at present any reason to believe
that man is highly sensitive to the evil effects of inter-breeding,
especially in areas so large as New Zealand, and the Sandwich archipelago
with its diversified stations.  On the contrary, it is known that the
present inhabitants of Norfolk Island are nearly all cousins or near
relations, as are the Todas in India, and the inhabitants of some of the
Western Islands of Scotland; and yet they seem not to have suffered in
fertility.  (45.  On the close relationship of the Norfolk Islanders, Sir
W. Denison, 'Varieties of Vice-Regal Life,' vol. i. 1870, p. 410.  For the
Todas, see Col. Marshall's work 1873, p. 110.  For the Western Islands of
Scotland, Dr. Mitchell, 'Edinburgh Medical Journal,' March to June, 1865.)

A much more probable view is suggested by the analogy of the lower animals.
The reproductive system can be shewn to be susceptible to an extraordinary
degree (though why we know not) to changed conditions of life; and this
susceptibility leads both to beneficial and to evil results.  A large
collection of facts on this subject is given in chap. xviii. of vol. ii. of
my 'Variation of Animals and Plants under Domestication.' I can here give
only the briefest abstract; and every one interested in the subject may
consult the above work.  Very slight changes increase the health, vigour,
and fertility of most or all organic beings, whilst other changes are known
to render a large number of animals sterile.  One of the most familiar
cases, is that of tamed elephants not breeding in India; though they often
breed in Ava, where the females are allowed to roam about the forests to
some extent, and are thus placed under more natural conditions.  The case
of various American monkeys, both sexes of which have been kept for many
years together in their own countries, and yet have very rarely or never
bred, is a more apposite instance, because of their relationship to man.
It is remarkable how slight a change in the conditions often induces
sterility in a wild animal when captured; and this is the more strange as
all our domesticated animals have become more fertile than they were in a
state of nature; and some of them can resist the most unnatural conditions
with undiminished fertility.  (46.  For the evidence on this head, see
'Variation of Animals,' etc., vol. ii. p. 111.)  Certain groups of animals
are much more liable than others to be affected by captivity; and generally
all the species of the same group are affected in the same manner.  But
sometimes a single species in a group is rendered sterile, whilst the
others are not so; on the other hand, a single species may retain its
fertility whilst most of the others fail to breed.  The males and females
of some species when confined, or when allowed to live almost, but not
quite free, in their native country, never unite; others thus circumstanced
frequently unite but never produce offspring; others again produce some
offspring, but fewer than in a state of nature; and as bearing on the above
cases of man, it is important to remark that the young are apt to be weak
and sickly, or malformed, and to perish at an early age.

Seeing how general is this law of the susceptibility of the reproductive
system to changed conditions of life, and that it holds good with our
nearest allies, the Quadrumana, I can hardly doubt that it applies to man
in his primeval state.  Hence if savages of any race are induced suddenly
to change their habits of life, they become more or less sterile, and their
young offspring suffer in health, in the same manner and from the same
cause, as do the elephant and hunting-leopard in India, many monkeys in
America, and a host of animals of all kinds, on removal from their natural
conditions.

We can see why it is that aborigines, who have long inhabited islands, and
who must have been long exposed to nearly uniform conditions, should be
specially affected by any change in their habits, as seems to be the case.
Civilised races can certainly resist changes of all kinds far better than
savages; and in this respect they resemble domesticated animals, for though
the latter sometimes suffer in health (for instance European dogs in
India), yet they are rarely rendered sterile, though a few such instances
have been recorded.  (47.  'Variation of Animals,' etc., vol. ii. p. 16.)
The immunity of civilised races and domesticated animals is probably due to
their having been subjected to a greater extent, and therefore having grown
somewhat more accustomed, to diversified or varying conditions, than the
majority of wild animals; and to their having formerly immigrated or been
carried from country to country, and to different families or sub-races
having inter-crossed.  It appears that a cross with civilised races at once
gives to an aboriginal race an immunity from the evil consequences of
changed conditions.  Thus the crossed offspring from the Tahitians and
English, when settled in Pitcairn Island, increased so rapidly that the
island was soon overstocked; and in June 1856 they were removed to Norfolk
Island.  They then consisted of 60 married persons and 134 children, making
a total of 194.  Here they likewise increased so rapidly, that although
sixteen of them returned to Pitcairn Island in 1859, they numbered in
January 1868, 300 souls; the males and females being in exactly equal
numbers.  What a contrast does this case present with that of the
Tasmanians; the Norfolk Islanders INCREASED in only twelve and a half years
from 194 to 300; whereas the Tasmanians DECREASED during fifteen years from
120 to 46, of which latter number only ten were children.  (48.  These
details are taken from 'The Mutineers of the "Bounty,"' by Lady Belcher,
1870; and from 'Pitcairn Island,' ordered to be printed by the House of
Commons, May 29, 1863.  The following statements about the Sandwich
Islanders are from the 'Honolulu Gazette,' and from Mr. Coan.)

So again in the interval between the census of 1866 and 1872 the natives of
full blood in the Sandwich Islands decreased by 8081, whilst the half-
castes, who are believed to be healthier, increased by 847; but I do not
know whether the latter number includes the offspring from the half-castes,
or only the half-castes of the first generation.

The cases which I have here given all relate to aborigines, who have been
subjected to new conditions as the result of the immigration of civilised
men.  But sterility and ill-health would probably follow, if savages were
compelled by any cause, such as the inroad of a conquering tribe, to desert
their homes and to change their habits.  It is an interesting circumstance
that the chief check to wild animals becoming domesticated, which implies
the power of their breeding freely when first captured, and one chief check
to wild men, when brought into contact with civilisation, surviving to form
a civilised race, is the same, namely, sterility from changed conditions of
life.

Finally, although the gradual decrease and ultimate extinction of the races
of man is a highly complex problem, depending on many causes which differ
in different places and at different times; it is the same problem as that
presented by the extinction of one of the higher animals--of the fossil
horse, for instance, which disappeared from South America, soon afterwards
to be replaced, within the same districts, by countless troups of the
Spanish horse.  The New Zealander seems conscious of this parallelism, for
he compares his future fate with that of the native rat now almost
exterminated by the European rat.  Though the difficulty is great to our
imagination, and really great, if we wish to ascertain the precise causes
and their manner of action, it ought not to be so to our reason, as long as
we keep steadily in mind that the increase of each species and each race is
constantly checked in various ways; so that if any new check, even a slight
one, be superadded, the race will surely decrease in number; and decreasing
numbers will sooner or later lead to extinction; the end, in most cases,
being promptly determined by the inroads of conquering tribes.

ON THE FORMATION OF THE RACES OF MAN.

In some cases the crossing of distinct races has led to the formation of a
new race.  The singular fact that the Europeans and Hindoos, who belong to
the same Aryan stock, and speak a language fundamentally the same, differ
widely in appearance, whilst Europeans differ but little from Jews, who
belong to the Semitic stock, and speak quite another language, has been
accounted for by Broca (49.  'On Anthropology,' translation,
'Anthropological Review,' Jan. 1868, p. 38.), through certain Aryan
branches having been largely crossed by indigenous tribes during their wide
diffusion.  When two races in close contact cross, the first result is a
heterogeneous mixture:  thus Mr. Hunter, in describing the Santali or hill-
tribes of India, says that hundreds of imperceptible gradations may be
traced "from the black, squat tribes of the mountains to the tall olive-
coloured Brahman, with his intellectual brow, calm eyes, and high but
narrow head"; so that it is necessary in courts of justice to ask the
witnesses whether they are Santalis or Hindoos.  (50.  'The Annals of Rural
Bengal,' 1868, p. 134.)  Whether a heterogeneous people, such as the
inhabitants of some of the Polynesian islands, formed by the crossing of
two distinct races, with few or no pure members left, would ever become
homogeneous, is not known from direct evidence.  But as with our
domesticated animals, a cross-breed can certainly be fixed and made uniform
by careful selection (51.  'The Variation of Animals and Plants under
Domestication,' vol. ii. p. 95.) in the course of a few generations, we may
infer that the free intercrossing of a heterogeneous mixture during a long
descent would supply the place of selection, and overcome any tendency to
reversion; so that the crossed race would ultimately become homogeneous,
though it might not partake in an equal degree of the characters of the two
parent-races.

Of all the differences between the races of man, the colour of the skin is
the most conspicuous and one of the best marked.  It was formerly thought
that differences of this kind could be accounted for by long exposure to
different climates; but Pallas first shewed that this is not tenable, and
he has since been followed by almost all anthropologists.  (52.  Pallas,
'Act. Acad. St. Petersburg,' 1780, part ii. p. 69.  He was followed by
Rudolphi, in his 'Beytrage zur Anthropologie,' 1812.  An excellent summary
of the evidence is given by Godron, 'De l'Espece,' 1859, vol. ii. p. 246,
etc.)  This view has been rejected chiefly because the distribution of the
variously coloured races, most of whom must have long inhabited their
present homes, does not coincide with corresponding differences of climate.
Some little weight may be given to such cases as that of the Dutch
families, who, as we hear on excellent authority (53.  Sir Andrew Smith, as
quoted by Knox, 'Races of Man,' 1850, p. 473.), have not undergone the
least change of colour after residing for three centuries in South Africa.
An argument on the same side may likewise be drawn from the uniform
appearance in various parts of the world of gipsies and Jews, though the
uniformity of the latter has been somewhat exaggerated.  (54.  See De
Quatrefages on this head, 'Revue des Cours Scientifiques,' Oct. 17, 1868,
p. 731.)  A very damp or a very dry atmosphere has been supposed to be more
influential in modifying the colour of the skin than mere heat; but as
D'Orbigny in South America, and Livingstone in Africa, arrived at
diametrically opposite conclusions with respect to dampness and dryness,
any conclusion on this head must be considered as very doubtful.  (55.
Livingstone's 'Travels and Researches in S. Africa,' 1857, pp. 338, 339.
D'Orbigny, as quoted by Godron, 'De l'Espece,' vol. ii. p. 266.)

Various facts, which I have given elsewhere, prove that the colour of the
skin and hair is sometimes correlated in a surprising manner with a
complete immunity from the action of certain vegetable poisons, and from
the attacks of certain parasites.  Hence it occurred to me, that negroes
and other dark races might have acquired their dark tints by the darker
individuals escaping from the deadly influence of the miasma of their
native countries, during a long series of generations.

I afterwards found that this same idea had long ago occurred to Dr. Wells.
(56.  See a paper read before the Royal Soc. in 1813, and published in his
Essays in 1818.  I have given an account of Dr. Wells' views in the
Historical Sketch (p. xvi.) to my 'Origin of Species.'  Various cases of
colour correlated with constitutional peculiarities are given in my
'Variation of Animals and Plants under Domestication,' vol. ii. pp. 227,
335.)  It has long been known that negroes, and even mulattoes, are almost
completely exempt from the yellow-fever, so destructive in tropical
America.  (57.  See, for instance, Nott and Gliddon, 'Types of Mankind,' p.
68.)  They likewise escape to a large extent the fatal intermittent fevers,
that prevail along at least 2600 miles of the shores of Africa, and which
annually cause one-fifth of the white settlers to die, and another fifth to
return home invalided.  (58.  Major Tulloch, in a paper read before the
Statistical Society, April 20, 1840, and given in the 'Athenaeum,' 1840, p.
353.)  This immunity in the negro seems to be partly inherent, depending on
some unknown peculiarity of constitution, and partly the result of
acclimatisation.  Pouchet (59.  'The Plurality of the Human Race'
(translat.), 1864, p. 60.) states that the negro regiments recruited near
the Soudan, and borrowed from the Viceroy of Egypt for the Mexican war,
escaped the yellow-fever almost equally with the negroes originally brought
from various parts of Africa and accustomed to the climate of the West
Indies.  That acclimatisation plays a part, is shewn by the many cases in
which negroes have become somewhat liable to tropical fevers, after having
resided for some time in a colder climate.  (60.  Quatrefages, 'Unite de
l'Espece Humaine,' 1861, p. 205.  Waitz, 'Introduction to Anthropology,'
translat., vol. i. 1863, p. 124.  Livingstone gives analogous cases in his
'Travels.')  The nature of the climate under which the white races have
long resided, likewise has some influence on them; for during the fearful
epidemic of yellow fever in Demerara during 1837, Dr. Blair found that the
death-rate of the immigrants was proportional to the latitude of the
country whence they had come.  With the negro the immunity, as far as it is
the result of acclimatisation, implies exposure during a prodigious length
of time; for the aborigines of tropical America who have resided there from
time immemorial, are not exempt from yellow fever; and the Rev. H.B.
Tristram states, that there are districts in Northern Africa which the
native inhabitants are compelled annually to leave, though the negroes can
remain with safety.

That the immunity of the negro is in any degree correlated with the colour
of his skin is a mere conjecture:  it may be correlated with some
difference in his blood, nervous system, or other tissues.  Nevertheless,
from the facts above alluded to, and from some connection apparently
existing between complexion and a tendency to consumption, the conjecture
seemed to me not improbable.  Consequently I endeavoured, with but little
success (61.  In the spring of 1862 I obtained permission from the
Director-General of the Medical department of the Army, to transmit to the
surgeons of the various regiments on foreign service a blank table, with
the following appended remarks, but I have received no returns.  "As
several well-marked cases have been recorded with our domestic animals of a
relation between the colour of the dermal appendages and the constitution;
and it being notorious that there is some limited degree of relation
between the colour of the races of man and the climate inhabited by them;
the following investigation seems worth consideration.  Namely, whether
there is any relation in Europeans between the colour of their hair, and
their liability to the diseases of tropical countries.  If the surgeons of
the several regiments, when stationed in unhealthy tropical districts,
would be so good as first to count, as a standard of comparison, how many
men, in the force whence the sick are drawn, have dark and light-coloured
hair, and hair of intermediate or doubtful tints; and if a similar account
were kept by the same medical gentlemen, of all the men who suffered from
malarious and yellow fevers, or from dysentery, it would soon be apparent,
after some thousand cases had been tabulated, whether there exists any
relation between the colour of the hair and constitutional liability to
tropical diseases.  Perhaps no such relation would be discovered, but the
investigation is well worth making.  In case any positive result were
obtained, it might be of some practical use in selecting men for any
particular service.  Theoretically the result would be of high interest, as
indicating one means by which a race of men inhabiting from a remote period
an unhealthy tropical climate, might have become dark-coloured by the
better preservation of dark-haired or dark-complexioned individuals during
a long succession of generations."), to ascertain how far it holds good.
The late Dr. Daniell, who had long lived on the West Coast of Africa, told
me that he did not believe in any such relation.  He was himself unusually
fair, and had withstood the climate in a wonderful manner.  When he first
arrived as a boy on the coast, an old and experienced negro chief predicted
from his appearance that this would prove the case.  Dr. Nicholson, of
Antigua, after having attended to this subject, writes to me that dark-
coloured Europeans escape the yellow fever more than those that are light-
coloured.  Mr. J.M. Harris altogether denies that Europeans with dark hair
withstand a hot climate better than other men:  on the contrary, experience
has taught him in making a selection of men for service on the coast of
Africa, to choose those with red hair.  (62.  'Anthropological Review,'
Jan. 1866, p. xxi.  Dr. Sharpe also says, with respect to India ('Man a
Special Creation,' 1873, p. 118), "that it has been noticed by some medical
officers that Europeans with light hair and florid complexions suffer less
from diseases of tropical countries than persons with dark hair and sallow
complexions; and, so far as I know, there appear to be good grounds for
this remark."  On the other hand, Mr. Heddle, of Sierra Leone, "who has had
more clerks killed under him than any other man," by the climate of the
West African Coast (W. Reade, 'African Sketch Book,' vol. ii. p. 522),
holds a directly opposite view, as does Capt. Burton.)  As far, therefore,
as these slight indications go, there seems no foundation for the
hypothesis, that blackness has resulted from the darker and darker
individuals having survived better during long exposure to fever-generating
miasma.

Dr. Sharpe remarks (63.  'Man a Special Creation,' 1873, p. 119.), that a
tropical sun, which burns and blisters a white skin, does not injure a
black one at all; and, as he adds, this is not due to habit in the
individual, for children only six or eight months old are often carried
about naked, and are not affected.  I have been assured by a medical man,
that some years ago during each summer, but not during the winter, his
hands became marked with light brown patches, like, although larger than
freckles, and that these patches were never affected by sun-burning, whilst
the white parts of his skin have on several occasions been much inflamed
and blistered.  With the lower animals there is, also, a constitutional
difference in liability to the action of the sun between those parts of the
skin clothed with white hair and other parts.  (64.  'Variation of Animals
and Plants under Domestication,' vol. ii. pp. 336, 337.)  Whether the
saving of the skin from being thus burnt is of sufficient importance to
account for a dark tint having been gradually acquired by man through
natural selection, I am unable to judge.  If it be so, we should have to
assume that the natives of tropical America have lived there for a much
shorter time than the Negroes in Africa, or the Papuans in the southern
parts of the Malay archipelago, just as the lighter-coloured Hindoos have
resided in India for a shorter time than the darker aborigines of the
central and southern parts of the peninsula.

Although with our present knowledge we cannot account for the differences
of colour in the races of man, through any advantage thus gained, or from
the direct action of climate; yet we must not quite ignore the latter
agency, for there is good reason to believe that some inherited effect is
thus produced.  (65.  See, for instance, Quatrefages ('Revue des Cours
Scientifiques,' Oct. 10, 1868, p. 724) on the effects of residence in
Abyssinia and Arabia, and other analogous cases.  Dr. Rolle ('Der Mensch,
seine Abstammung,' etc., 1865, s. 99) states, on the authority of Khanikof,
that the greater number of German families settled in Georgia, have
acquired in the course of two generations dark hair and eyes.  Mr. D.
Forbes informs me that the Quichuas in the Andes vary greatly in colour,
according to the position of the valleys inhabited by them.)

We have seen in the second chapter that the conditions of life affect the
development of the bodily frame in a direct manner, and that the effects
are transmitted.  Thus, as is generally admitted, the European settlers in
the United States undergo a slight but extraordinary rapid change of
appearance.  Their bodies and limbs become elongated; and I hear from Col.
Bernys that during the late war in the United States, good evidence was
afforded of this fact by the ridiculous appearance presented by the German
regiments, when dressed in ready-made clothes manufactured for the American
market, and which were much too long for the men in every way.  There is,
also, a considerable body of evidence shewing that in the Southern States
the house-slaves of the third generation present a markedly different
appearance from the field-slaves.  (66.  Harlan, 'Medical Researches,' p.
532.  Quatrefages ('Unite de l'Espece Humaine,' 1861, p. 128) has collected
much evidence on this head.)

If, however, we look to the races of man as distributed over the world, we
must infer that their characteristic differences cannot be accounted for by
the direct action of different conditions of life, even after exposure to
them for an enormous period of time.  The Esquimaux live exclusively on
animal food; they are clothed in thick fur, and are exposed to intense cold
and to prolonged darkness; yet they do not differ in any extreme degree
from the inhabitants of Southern China, who live entirely on vegetable
food, and are exposed almost naked to a hot, glaring climate.  The
unclothed Fuegians live on the marine productions of their inhospitable
shores; the Botocudos of Brazil wander about the hot forests of the
interior and live chiefly on vegetable productions; yet these tribes
resemble each other so closely that the Fuegians on board the "Beagle" were
mistaken by some Brazilians for Botocudos.  The Botocudos again, as well as
the other inhabitants of tropical America, are wholly different from the
Negroes who inhabit the opposite shores of the Atlantic, are exposed to a
nearly similar climate, and follow nearly the same habits of life.

Nor can the differences between the races of man be accounted for by the
inherited effects of the increased or decreased use of parts, except to a
quite insignificant degree.  Men who habitually live in canoes, may have
their legs somewhat stunted; those who inhabit lofty regions may have their
chests enlarged; and those who constantly use certain sense-organs may have
the cavities in which they are lodged somewhat increased in size, and their
features consequently a little modified.  With civilised nations, the
reduced size of the jaws from lessened use--the habitual play of different
muscles serving to express different emotions--and the increased size of
the brain from greater intellectual activity, have together produced a
considerable effect on their general appearance when compared with savages.
(67.  See Prof. Schaaffhausen, translat., in 'Anthropological Review,' Oct.
1868, p. 429.)  Increased bodily stature, without any corresponding
increase in the size of the brain, may (judging from the previously adduced
case of rabbits), have given to some races an elongated skull of the
dolichocephalic type.

Lastly, the little-understood principle of correlated development has
sometimes come into action, as in the case of great muscular development
and strongly projecting supra-orbital ridges.  The colour of the skin and
hair are plainly correlated, as is the texture of the hair with its colour
in the Mandans of North America.  (68.  Mr. Catlin states ('N. American
Indians,' 3rd ed., 1842, vol. i. p. 49) that in the whole tribe of the
Mandans, about one in ten or twelve of the members, of all ages and both
sexes, have bright silvery grey hair, which is hereditary.  Now this hair
is as coarse and harsh as that of a horse's mane, whilst the hair of other
colours is fine and soft.)  The colour also of the skin, and the odour
emitted by it, are likewise in some manner connected.  With the breeds of
sheep the number of hairs within a given space and the number of excretory
pores are related.  (69.  On the odour of the skin, Godron, 'Sur l'Espece,'
tom. ii. p. 217.  On the pores in the skin, Dr. Wilckens, 'Die Aufgaben der
Landwirth. Zootechnik,' 1869, s. 7.)  If we may judge from the analogy of
our domesticated animals, many modifications of structure in man probably
come under this principle of correlated development.

We have now seen that the external characteristic differences between the
races of man cannot be accounted for in a satisfactory manner by the direct
action of the conditions of life, nor by the effects of the continued use
of parts, nor through the principle of correlation.  We are therefore led
to enquire whether slight individual differences, to which man is eminently
liable, may not have been preserved and augmented during a long series of
generations through natural selection.  But here we are at once met by the
objection that beneficial variations alone can be thus preserved; and as
far as we are enabled to judge, although always liable to err on this head,
none of the differences between the races of man are of any direct or
special service to him.  The intellectual and moral or social faculties
must of course be excepted from this remark.  The great variability of all
the external differences between the races of man, likewise indicates that
they cannot be of much importance; for if important, they would long ago
have been either fixed and preserved, or eliminated.  In this respect man
resembles those forms, called by naturalists protean or polymorphic, which
have remained extremely variable, owing, as it seems, to such variations
being of an indifferent nature, and to their having thus escaped the action
of natural selection.

We have thus far been baffled in all our attempts to account for the
differences between the races of man; but there remains one important
agency, namely Sexual Selection, which appears to have acted powerfully on
man, as on many other animals.  I do not intend to assert that sexual
selection will account for all the differences between the races.  An
unexplained residuum is left, about which we can only say, in our
ignorance, that as individuals are continually born with, for instance,
heads a little rounder or narrower, and with noses a little longer or
shorter, such slight differences might become fixed and uniform, if the
unknown agencies which induced them were to act in a more constant manner,
aided by long-continued intercrossing.  Such variations come under the
provisional class, alluded to in our second chapter, which for want of a
better term are often called spontaneous.  Nor do I pretend that the
effects of sexual selection can be indicated with scientific precision; but
it can be shewn that it would be an inexplicable fact if man had not been
modified by this agency, which appears to have acted powerfully on
innumerable animals.  It can further be shewn that the differences between
the races of man, as in colour, hairiness, form of features, etc., are of a
kind which might have been expected to come under the influence of sexual
selection.  But in order to treat this subject properly, I have found it
necessary to pass the whole animal kingdom in review.  I have therefore
devoted to it the Second Part of this work.  At the close I shall return to
man, and, after attempting to shew how far he has been modified through
sexual selection, will give a brief summary of the chapters in this First
Part.


NOTE ON THE RESEMBLANCES AND DIFFERENCES IN THE STRUCTURE AND THE
DEVELOPMENT OF THE BRAIN IN MAN AND APES BY PROFESSOR HUXLEY, F.R.S.

The controversy respecting the nature and the extent of the differences in
the structure of the brain in man and the apes, which arose some fifteen
years ago, has not yet come to an end, though the subject matter of the
dispute is, at present, totally different from what it was formerly.  It
was originally asserted and re-asserted, with singular pertinacity, that
the brain of all the apes, even the highest, differs from that of man, in
the absence of such conspicuous structures as the posterior lobes of the
cerebral hemispheres, with the posterior cornu of the lateral ventricle and
the hippocampus minor, contained in those lobes, which are so obvious in
man.

But the truth that the three structures in question are as well developed
in apes' as in human brains, or even better; and that it is characteristic
of all the Primates (if we exclude the Lemurs) to have these parts well
developed, stands at present on as secure a basis as any proposition in
comparative anatomy.  Moreover, it is admitted by every one of the long
series of anatomists who, of late years, have paid special attention to the
arrangement of the complicated sulci and gyri which appear upon the surface
of the cerebral hemispheres in man and the higher apes, that they are
disposed after the very same pattern in him, as in them.  Every principal
gyrus and sulcus of a chimpanzee's brain is clearly represented in that of
a man, so that the terminology which applies to the one answers for the
other.  On this point there is no difference of opinion.  Some years since,
Professor Bischoff published a memoir (70.  'Die Grosshirn-Windungen des
Menschen;' 'Abhandlungen der K. Bayerischen Akademie,' B. x. 1868.) on the
cerebral convolutions of man and apes; and as the purpose of my learned
colleague was certainly not to diminish the value of the differences
between apes and men in this respect, I am glad to make a citation from
him.

"That the apes, and especially the orang, chimpanzee and gorilla, come very
close to man in their organisation, much nearer than to any other animal,
is a well known fact, disputed by nobody.  Looking at the matter from the
point of view of organisation alone, no one probably would ever have
disputed the view of Linnaeus, that man should be placed, merely as a
peculiar species, at the head of the mammalia and of those apes.  Both
shew, in all their organs, so close an affinity, that the most exact
anatomical investigation is needed in order to demonstrate those
differences which really exist.  So it is with the brains.  The brains of
man, the orang, the chimpanzee, the gorilla, in spite of all the important
differences which they present, come very close to one another" (loc. cit.
p. 101).

There remains, then, no dispute as to the resemblance in fundamental
characters, between the ape's brain and man's:  nor any as to the
wonderfully close similarity between the chimpanzee, orang and man, in even
the details of the arrangement of the gyri and sulci of the cerebral
hemispheres.  Nor, turning to the differences between the brains of the
highest apes and that of man, is there any serious question as to the
nature and extent of these differences.  It is admitted that the man's
cerebral hemispheres are absolutely and relatively larger than those of the
orang and chimpanzee; that his frontal lobes are less excavated by the
upward protrusion of the roof of the orbits; that his gyri and sulci are,
as a rule, less symmetrically disposed, and present a greater number of
secondary plications.  And it is admitted that, as a rule, in man, the
temporo-occipital or "external perpendicular" fissure, which is usually so
strongly marked a feature of the ape's brain is but faintly marked.  But it
is also clear, that none of these differences constitutes a sharp
demarcation between the man's and the ape's brain.  In respect to the
external perpendicular fissure of Gratiolet, in the human brain for
instance, Professor Turner remarks:  (71.  'Convolutions of the Human
Cerebrum Topographically Considered,' 1866, p. 12.)

"In some brains it appears simply as an indentation of the margin of the
hemisphere, but, in others, it extends for some distance more or less
transversely outwards.  I saw it in the right hemisphere of a female brain
pass more than two inches outwards; and on another specimen, also the right
hemisphere, it proceeded for four-tenths of an inch outwards, and then
extended downwards, as far as the lower margin of the outer surface of the
hemisphere.  The imperfect definition of this fissure in the majority of
human brains, as compared with its remarkable distinctness in the brain of
most Quadrumana, is owing to the presence, in the former, of certain
superficial, well marked, secondary convolutions which bridge it over and
connect the parietal with the occipital lobe.  The closer the first of
these bridging gyri lies to the longitudinal fissure, the shorter is the
external parieto-occipital fissure" (loc. cit. p. 12).

The obliteration of the external perpendicular fissure of Gratiolet,
therefore, is not a constant character of the human brain.  On the other
hand, its full development is not a constant character of the higher ape's
brain.  For, in the chimpanzee, the more or less extensive obliteration of
the external perpendicular sulcus by "bridging convolutions," on one side
or the other, has been noted over and over again by Prof. Rolleston, Mr.
Marshall, M. Broca and Professor Turner.  At the conclusion of a special
paper on this subject the latter writes:  (72.  Notes more especially on
the bridging convolutions in the Brain of the Chimpanzee, 'Proceedings of
the Royal Society of Edinburgh,' 1865-6.)

"The three specimens of the brain of a chimpanzee, just described, prove,
that the generalisation which Gratiolet has attempted to draw of the
complete absence of the first connecting convolution and the concealment of
the second, as essentially characteristic features in the brain of this
animal, is by no means universally applicable.  In only one specimen did
the brain, in these particulars, follow the law which Gratiolet has
expressed.  As regards the presence of the superior bridging convolution, I
am inclined to think that it has existed in one hemisphere, at least, in a
majority of the brains of this animal which have, up to this time, been
figured or described.  The superficial position of the second bridging
convolution is evidently less frequent, and has as yet, I believe, only
been seen in the brain (A) recorded in this communication.  The
asymmetrical arrangement in the convolutions of the two hemispheres, which
previous observers have referred to in their descriptions, is also well
illustrated in these specimens" (pp. 8, 9).

Even were the presence of the temporo-occipital, or external perpendicular,
sulcus, a mark of distinction between the higher apes and man, the value of
such a distinctive character would be rendered very doubtful by the
structure of the brain in the Platyrrhine apes.  In fact, while the
temporo-occipital is one of the most constant of sulci in the Catarrhine,
or Old World, apes, it is never very strongly developed in the New World
apes; it is absent in the smaller Platyrrhini; rudimentary in Pithecia (73.
Flower, 'On the Anatomy of Pithecia Monachus,' 'Proceedings of the
Zoological Society,' 1862.); and more or less obliterated by bridging
convolutions in Ateles.

A character which is thus variable within the limits of a single group can
have no great taxonomic value.

It is further established, that the degree of asymmetry of the convolution
of the two sides in the human brain is subject to much individual
variation; and that, in those individuals of the Bushman race who have been
examined, the gyri and sulci of the two hemispheres are considerably less
complicated and more symmetrical than in the European brain, while, in some
individuals of the chimpanzee, their complexity and asymmetry become
notable.  This is particularly the case in the brain of a young male
chimpanzee figured by M. Broca.  ('L'ordre des Primates,' p. 165, fig. 11.)

Again, as respects the question of absolute size, it is established that
the difference between the largest and the smallest healthy human brain is
greater than the difference between the smallest healthy human brain and
the largest chimpanzee's or orang's brain.

Moreover, there is one circumstance in which the orang's and chimpanzee's
brains resemble man's, but in which they differ from the lower apes, and
that is the presence of two corpora candicantia--the Cynomorpha having but
one.

In view of these facts I do not hesitate in this year 1874, to repeat and
insist upon the proposition which I enunciated in 1863:  (74.  'Man's Place
in Nature,' p. 102.)

"So far as cerebral structure goes, therefore, it is clear that man differs
less from the chimpanzee or the orang, than these do even from the monkeys,
and that the difference between the brain of the chimpanzee and of man is
almost insignificant when compared with that between the chimpanzee brain
and that of a Lemur."

In the paper to which I have referred, Professor Bischoff does not deny the
second part of this statement, but he first makes the irrelevant remark
that it is not wonderful if the brains of an orang and a Lemur are very
different; and secondly, goes on to assert that, "If we successively
compare the brain of a man with that of an orang; the brain of this with
that of a chimpanzee; of this with that of a gorilla, and so on of a
Hylobates, Semnopithecus, Cynocephalus, Cercopithecus, Macacus, Cebus,
Callithrix, Lemur, Stenops, Hapale, we shall not meet with a greater, or
even as great a, break in the degree of development of the convolutions, as
we find between the brain of a man and that of an orang or chimpanzee."

To which I reply, firstly, that whether this assertion be true or false, it
has nothing whatever to do with the proposition enunciated in 'Man's Place
in Nature,' which refers not to the development of the convolutions alone,
but to the structure of the whole brain.  If Professor Bischoff had taken
the trouble to refer to p. 96 of the work he criticises, in fact, he would
have found the following passage:  "And it is a remarkable circumstance
that though, so far as our present knowledge extends, there IS one true
structural break in the series of forms of Simian brains, this hiatus does
not lie between man and the manlike apes, but between the lower and the
lowest Simians, or in other words, between the Old and New World apes and
monkeys and the Lemurs.  Every Lemur which has yet been examined, in fact,
has its cerebellum partially visible from above; and its posterior lobe,
with the contained posterior cornu and hippocampus minor, more or less
rudimentary.  Every marmoset, American monkey, Old World monkey, baboon or
manlike ape, on the contrary, has its cerebellum entirely hidden,
posteriorly, by the cerebral lobes, and possesses a large posterior cornu
with a well-developed hippocampus minor."

This statement was a strictly accurate account of what was known when it
was made; and it does not appear to me to be more than apparently weakened
by the subsequent discovery of the relatively small development of the
posterior lobes in the Siamang and in the Howling monkey.  Notwithstanding
the exceptional brevity of the posterior lobes in these two species, no one
will pretend that their brains, in the slightest degree, approach those of
the Lemurs.  And if, instead of putting Hapale out of its natural place, as
Professor Bischoff most unaccountably does, we write the series of animals
he has chosen to mention as follows:  Homo, Pithecus, Troglodytes,
Hylobates, Semnopithecus, Cynocephalus, Cercopithecus, Macacus, Cebus,
Callithrix, Hapale, Lemur, Stenops, I venture to reaffirm that the great
break in this series lies between Hapale and Lemur, and that this break is
considerably greater than that between any other two terms of that series.
Professor Bischoff ignores the fact that long before he wrote, Gratiolet
had suggested the separation of the Lemurs from the other Primates on the
very ground of the difference in their cerebral characters; and that
Professor Flower had made the following observations in the course of his
description of the brain of the Javan Loris:  (75.  'Transactions of the
Zoological Society,' vol. v. 1862.)

"And it is especially remarkable that, in the development of the posterior
lobes, there is no approximation to the Lemurine, short hemisphered brain,
in those monkeys which are commonly supposed to approach this family in
other respects, viz. the lower members of the Platyrrhine group."

So far as the structure of the adult brain is concerned, then, the very
considerable additions to our knowledge, which have been made by the
researches of so many investigators, during the past ten years, fully
justify the statement which I made in 1863.  But it has been said, that,
admitting the similarity between the adult brains of man and apes, they are
nevertheless, in reality, widely different, because they exhibit
fundamental differences in the mode of their development.  No one would be
more ready than I to admit the force of this argument, if such fundamental
differences of development really exist.  But I deny that they do exist.
On the contrary, there is a fundamental agreement in the development of the
brain in men and apes.

Gratiolet originated the statement that there is a fundamental difference
in the development of the brains of apes and that of man--consisting in
this; that, in the apes, the sulci which first make their appearance are
situated on the posterior region of the cerebral hemispheres, while, in the
human foetus, the sulci first become visible on the frontal lobes.  (76.
Chez tous les singes, les plis posterieurs se developpent les premiers;
les plis anterieurs se developpent plus tard, aussi la vertebre occipitale
et la parietale sont-elles relativement tres-grandes chez le foetus.
L'Homme presente une exception remarquable quant a l'epoque de l'apparition
des plis frontaux, qui sont les premiers indiques; mais le developpement
general du lobe frontal, envisage seulement par rapport a son volume, suit
les memes lois que dans les singes:  Gratiolet, 'Memoire sur les plis
cerebres de l'Homme et des Primateaux,' p. 39, Tab. iv, fig. 3.)

This general statement is based upon two observations, the one of a Gibbon
almost ready to be born, in which the posterior gyri were "well developed,"
while those of the frontal lobes were "hardly indicated" (77.  Gratiolet's
words are (loc. cit. p. 39):  "Dans le foetus dont il s'agit les plis
cerebraux posterieurs sont bien developpes, tandis que les plis du lobe
frontal sont a peine indiques."  The figure, however (Pl. iv, fig. 3),
shews the fissure of Rolando, and one of the frontal sulci plainly enough.
Nevertheless, M. Alix, in his 'Notice sur les travaux anthropologiques de
Gratiolet' ('Mem. de la Societe d'Anthropologie de Paris,' 1868, page 32),
writes thus:  "Gratiolet a eu entre les mains le cerveau d'un foetus de
Gibbon, singe eminemment superieur, et tellement rapproche de l'orang, que
des naturalistes tres-competents l'ont range parmi les anthropoides.  M.
Huxley, par exemple, n'hesite pas sur ce point.  Eh bien, c'est sur le
cerveau d'un foetus de Gibbon que Gratiolet a vu LES CIRCONVOLUTIONS DU
LOBE TEMPORO-SPHENOIDAL DEJA DEVELOPPEES LORSQU'IL N'EXISTENT PAS ENCORE DE
PLIS SUR LE LOBE FRONTAL.  Il etait donc bien autorise a dire que, chez
l'homme les circonvolutions apparaissent d'a en w, tandis que chez les
singes elles se developpent d'w en a."), and the other of a human foetus at
the 22nd or 23rd week of uterogestation, in which Gratiolet notes that the
insula was uncovered, but that nevertheless "des incisures sement de lobe
anterieur, une scissure peu profonde indique la separation du lobe
occipital, tres-reduit, d'ailleurs des cette epoque.  Le reste de la
surface cerebrale est encore absolument lisse."

Three views of this brain are given in Plate II, figs. 1, 2, 3, of the work
cited, shewing the upper, lateral and inferior views of the hemispheres,
but not the inner view.  It is worthy of note that the figure by no means
bears out Gratiolet's description, inasmuch as the fissure (antero-
temporal) on the posterior half of the face of the hemisphere is more
marked than any of those vaguely indicated in the anterior half.  If the
figure is correct, it in no way justifies Gratiolet's conclusion:  "Il y a
donc entre ces cerveaux [those of a Callithrix and of a Gibbon] et celui du
foetus humain une difference fondamental.  Chez celui-ci, longtemps avant
que les plis temporaux apparaissent, les plis frontaux, ESSAYENT
d'exister."

Since Gratiolet's time, however, the development of the gyri and sulci of
the brain has been made the subject of renewed investigation by Schmidt,
Bischoff, Pansch (78.  'Ueber die typische Anordnung der Furchen und
Windungen auf den Grosshirn-Hemisphaeren des Menschen und der Affen,'
'Archiv fuer Anthropologie,' iii. 1868.), and more particularly by Ecker
(79.  'Zur Entwicklungs Geschichte der Furchen und Windungen der Grosshirn-
Hemisphaeren im Foetus des Menschen,'  'Archiv fuer Anthropologie,' iii.
1868.), whose work is not only the latest, but by far the most complete,
memoir on the subject.

The final results of their inquiries may be summed up as follows:--

1.  In the human foetus, the sylvian fissure is formed in the course of the
third month of uterogestation.  In this, and in the fourth month, the
cerebral hemispheres are smooth and rounded (with the exception of the
sylvian depression), and they project backwards far beyond the cerebellum.

2.  The sulci, properly so called, begin to appear in the interval between
the end of the fourth and the beginning of the sixth month of foetal life,
but Ecker is careful to point out that, not only the time, but the order,
of their appearance is subject to considerable individual variation.  In no
case, however, are either the frontal or the temporal sulci the earliest.

The first which appears, in fact, lies on the inner face of the hemisphere
(whence doubtless Gratiolet, who does not seem to have examined that face
in his foetus, overlooked it), and is either the internal perpendicular
(occipito-parietal), or the calcarine sulcus, these two being close
together and eventually running into one another.  As a rule the occipito-
parietal is the earlier of the two.

3.  At the latter part of this period, another sulcus, the "posterio-
parietal," or "Fissure of Rolando" is developed, and it is followed, in the
course of the sixth month, by the other principal sulci of the frontal,
parietal, temporal and occipital lobes.  There is, however, no clear
evidence that one of these constantly appears before the other; and it is
remarkable that, in the brain at the period described and figured by Ecker
(loc. cit. pp. 212-213, Taf. II, figs. 1, 2, 3, 4), the antero-temporal
sulcus (scissure parallele) so characteristic of the ape's brain, is as
well, if not better developed than the fissure of Rolando, and is much more
marked than the proper frontal sulci.

Taking the facts as they now stand, it appears to me that the order of the
appearance of the sulci and gyri in the foetal human brain is in perfect
harmony with the general doctrine of evolution, and with the view that man
has been evolved from some ape-like form; though there can be no doubt that
form was, in many respects, different from any member of the Primates now
living.

Von Baer taught us, half a century ago, that, in the course of their
development, allied animals put on at first, the characters of the greater
groups to which they belong, and, by degrees, assume those which restrict
them within the limits of their family, genus, and species; and he proved,
at the same time, that no developmental stage of a higher animal is
precisely similar to the adult condition of any lower animal.  It is quite
correct to say that a frog passes through the condition of a fish, inasmuch
as at one period of its life the tadpole has all the characters of a fish,
and if it went no further, would have to be grouped among fishes.  But it
is equally true that a tadpole is very different from any known fish.

In like manner, the brain of a human foetus, at the fifth month, may
correctly be said to be, not only the brain of an ape, but that of an
Arctopithecine or marmoset-like ape; for its hemispheres, with their great
posterior lobster, and with no sulci but the sylvian and the calcarine,
present the characteristics found only in the group of the Arctopithecine
Primates.  But it is equally true, as Gratiolet remarks, that, in its
widely open sylvian fissure, it differs from the brain of any actual
marmoset.  No doubt it would be much more similar to the brain of an
advanced foetus of a marmoset.  But we know nothing whatever of the
development of the brain in the marmosets.  In the Platyrrhini proper, the
only observation with which I am acquainted is due to Pansch, who found in
the brain of a foetal Cebus Apella, in addition to the sylvian fissure and
the deep calcarine fissure, only a very shallow antero-temporal fissure
(scissure parallele of Gratiolet).

Now this fact, taken together with the circumstance that the antero-
temporal sulcus is present in such Platyrrhini as the Saimiri, which
present mere traces of sulci on the anterior half of the exterior of the
cerebral hemispheres, or none at all, undoubtedly, so far as it goes,
affords fair evidence in favour of Gratiolet's hypothesis, that the
posterior sulci appear before the anterior, in the brains of the
Platyrrhini.  But, it by no means follows, that the rule which may hold
good for the Platyrrhini extends to the Catarrhini.  We have no information
whatever respecting the development of the brain in the Cynomorpha; and, as
regards the Anthropomorpha, nothing but the account of the brain of the
Gibbon, near birth, already referred to.  At the present moment there is
not a shadow of evidence to shew that the sulci of a chimpanzee's, or
orang's, brain do not appear in the same order as a man's.

Gratiolet opens his preface with the aphorism:  "Il est dangereux dans les
sciences de conclure trop vite."  I fear he must have forgotten this sound
maxim by the time he had reached the discussion of the differences between
men and apes, in the body of his work.  No doubt, the excellent author of
one of the most remarkable contributions to the just understanding of the
mammalian brain which has ever been made, would have been the first to
admit the insufficiency of his data had he lived to profit by the advance
of inquiry.  The misfortune is that his conclusions have been employed by
persons incompetent to appreciate their foundation, as arguments in favour
of obscurantism.  (80.  For example, M. l'Abbe Lecomte in his terrible
pamphlet, 'Le Darwinisme et l'origine de l'Homme,' 1873.)

But it is important to remark that, whether Gratiolet was right or wrong in
his hypothesis respecting the relative order of appearance of the temporal
and frontal sulci, the fact remains; that before either temporal or frontal
sulci, appear, the foetal brain of man presents characters which are found
only in the lowest group of the Primates (leaving out the Lemurs); and that
this is exactly what we should expect to be the case, if man has resulted
from the gradual modification of the same form as that from which the other
Primates have sprung.



PART II.  SEXUAL SELECTION.


CHAPTER VIII.

PRINCIPLES OF SEXUAL SELECTION.

Secondary sexual characters--Sexual selection--Manner of action--Excess of
males--Polygamy--The male alone generally modified through sexual
selection--Eagerness of the male--Variability of the male--Choice exerted
by the female--Sexual compared with natural selection--Inheritance, at
corresponding periods of life, at corresponding seasons of the year, and as
limited by sex--Relations between the several forms of inheritance--Causes
why one sex and the young are not modified through sexual selection--
Supplement on the proportional numbers of the two sexes throughout the
animal kingdom--The proportion of the sexes in relation to natural
selection.

With animals which have their sexes separated, the males necessarily differ
from the females in their organs of reproduction; and these are the primary
sexual characters.  But the sexes often differ in what Hunter has called
secondary sexual characters, which are not directly connected with the act
of reproduction; for instance, the male possesses certain organs of sense
or locomotion, of which the female is quite destitute, or has them more
highly-developed, in order that he may readily find or reach her; or again
the male has special organs of prehension for holding her securely.  These
latter organs, of infinitely diversified kinds, graduate into those which
are commonly ranked as primary, and in some cases can hardly be
distinguished from them; we see instances of this in the complex appendages
at the apex of the abdomen in male insects.  Unless indeed we confine the
term "primary" to the reproductive glands, it is scarcely possible to
decide which ought to be called primary and which secondary.

The female often differs from the male in having organs for the nourishment
or protection of her young, such as the mammary glands of mammals, and the
abdominal sacks of the marsupials.  In some few cases also the male
possesses similar organs, which are wanting in the female, such as the
receptacles for the ova in certain male fishes, and those temporarily
developed in certain male frogs.  The females of most bees are provided
with a special apparatus for collecting and carrying pollen, and their
ovipositor is modified into a sting for the defence of the larvae and the
community.  Many similar cases could be given, but they do not here concern
us.  There are, however, other sexual differences quite unconnected with
the primary reproductive organs, and it is with these that we are more
especially concerned--such as the greater size, strength, and pugnacity of
the male, his weapons of offence or means of defence against rivals, his
gaudy colouring and various ornaments, his power of song, and other such
characters.

Besides the primary and secondary sexual differences, such as the
foregoing, the males and females of some animals differ in structures
related to different habits of life, and not at all, or only indirectly, to
the reproductive functions.  Thus the females of certain flies (Culicidae
and Tabanidae) are blood-suckers, whilst the males, living on flowers, have
mouths destitute of mandibles.  (1.  Westwood, 'Modern Classification of
Insects,' vol. ii. 1840, p. 541.  For the statement about Tanais, mentioned
below, I am indebted to Fritz Muller.)  The males of certain moths and of
some crustaceans (e.g. Tanais) have imperfect, closed mouths, and cannot
feed.  The complemental males of certain Cirripedes live like epiphytic
plants either on the female or the hermaphrodite form, and are destitute of
a mouth and of prehensile limbs.  In these cases it is the male which has
been modified, and has lost certain important organs, which the females
possess.  In other cases it is the female which has lost such parts; for
instance, the female glow-worm is destitute of wings, as also are many
female moths, some of which never leave their cocoons.  Many female
parasitic crustaceans have lost their natatory legs.  In some weevil-
beetles (Curculionidae) there is a great difference between the male and
female in the length of the rostrum or snout (2.  Kirby and Spence,
'Introduction to Entomology,' vol. iii. 1826, p. 309.); but the meaning of
this and of many analogous differences, is not at all understood.
Differences of structure between the two sexes in relation to different
habits of life are generally confined to the lower animals; but with some
few birds the beak of the male differs from that of the female.  In the
Huia of New Zealand the difference is wonderfully great, and we hear from
Dr. Buller (3.  'Birds of New Zealand,' 1872, p. 66.) that the male uses
his strong beak in chiselling the larvae of insects out of decayed wood,
whilst the female probes the softer parts with her far longer, much curved
and pliant beak:  and thus they mutually aid each other.  In most cases,
differences of structure between the sexes are more or less directly
connected with the propagation of the species:  thus a female, which has to
nourish a multitude of ova, requires more food than the male, and
consequently requires special means for procuring it.  A male animal, which
lives for a very short time, might lose its organs for procuring food
through disuse, without detriment; but he would retain his locomotive
organs in a perfect state, so that he might reach the female.  The female,
on the other hand, might safely lose her organs for flying, swimming, or
walking, if she gradually acquired habits which rendered such powers
useless.

We are, however, here concerned only with sexual selection.  This depends
on the advantage which certain individuals have over others of the same sex
and species solely in respect of reproduction.  When, as in the cases above
mentioned, the two sexes differ in structure in relation to different
habits of life, they have no doubt been modified through natural selection,
and by inheritance limited to one and the same sex.  So again the primary
sexual organs, and those for nourishing or protecting the young, come under
the same influence; for those individuals which generated or nourished
their offspring best, would leave, ceteris paribus, the greatest number to
inherit their superiority; whilst those which generated or nourished their
offspring badly, would leave but few to inherit their weaker powers.  As
the male has to find the female, he requires organs of sense and
locomotion, but if these organs are necessary for the other purposes of
life, as is generally the case, they will have been developed through
natural selection.  When the male has found the female, he sometimes
absolutely requires prehensile organs to hold her; thus Dr. Wallace informs
me that the males of certain moths cannot unite with the females if their
tarsi or feet are broken.  The males of many oceanic crustaceans, when
adult, have their legs and antennae modified in an extraordinary manner for
the prehension of the female; hence we may suspect that it is because these
animals are washed about by the waves of the open sea, that they require
these organs in order to propagate their kind, and if so, their development
has been the result of ordinary or natural selection.  Some animals
extremely low in the scale have been modified for this same purpose; thus
the males of certain parasitic worms, when fully grown, have the lower
surface of the terminal part of their bodies roughened like a rasp, and
with this they coil round and permanently hold the females.  (4.  M.
Perrier advances this case ('Revue Scientifique,' Feb. 1, 1873, p. 865) as
one fatal to the belief in sexual election, inasmuch as he supposes that I
attribute all the differences between the sexes to sexual selection.  This
distinguished naturalist, therefore, like so many other Frenchmen, has not
taken the trouble to understand even the first principles of sexual
selection.  An English naturalist insists that the claspers of certain male
animals could not have been developed through the choice of the female!
Had I not met with this remark, I should not have thought it possible for
any one to have read this chapter and to have imagined that I maintain that
the choice of the female had anything to do with the development of the
prehensile organs in the male.)

When the two sexes follow exactly the same habits of life, and the male has
the sensory or locomotive organs more highly developed than those of the
female, it may be that the perfection of these is indispensable to the male
for finding the female; but in the vast majority of cases, they serve only
to give one male an advantage over another, for with sufficient time, the
less well-endowed males would succeed in pairing with the females; and
judging from the structure of the female, they would be in all other
respects equally well adapted for their ordinary habits of life.  Since in
such cases the males have acquired their present structure, not from being
better fitted to survive in the struggle for existence, but from having
gained an advantage over other males, and from having transmitted this
advantage to their male offspring alone, sexual selection must here have
come into action.  It was the importance of this distinction which led me
to designate this form of selection as Sexual Selection.  So again, if the
chief service rendered to the male by his prehensile organs is to prevent
the escape of the female before the arrival of other males, or when
assaulted by them, these organs will have been perfected through sexual
selection, that is by the advantage acquired by certain individuals over
their rivals.  But in most cases of this kind it is impossible to
distinguish between the effects of natural and sexual selection.  Whole
chapters could be filled with details on the differences between the sexes
in their sensory, locomotive, and prehensile organs.  As, however, these
structures are not more interesting than others adapted for the ordinary
purposes of life I shall pass them over almost entirely, giving only a few
instances under each class.

There are many other structures and instincts which must have been
developed through sexual selection--such as the weapons of offence and the
means of defence of the males for fighting with and driving away their
rivals--their courage and pugnacity--their various ornaments--their
contrivances for producing vocal or instrumental music--and their glands
for emitting odours, most of these latter structures serving only to allure
or excite the female.  It is clear that these characters are the result of
sexual and not of ordinary selection, since unarmed, unornamented, or
unattractive males would succeed equally well in the battle for life and in
leaving a numerous progeny, but for the presence of better endowed males.
We may infer that this would be the case, because the females, which are
unarmed and unornamented, are able to survive and procreate their kind.
Secondary sexual characters of the kind just referred to, will be fully
discussed in the following chapters, as being in many respects interesting,
but especially as depending on the will, choice, and rivalry of the
individuals of either sex.  When we behold two males fighting for the
possession of the female, or several male birds displaying their gorgeous
plumage, and performing strange antics before an assembled body of females,
we cannot doubt that, though led by instinct, they know what they are
about, and consciously exert their mental and bodily powers.

Just as man can improve the breeds of his game-cocks by the selection of
those birds which are victorious in the cockpit, so it appears that the
strongest and most vigorous males, or those provided with the best weapons,
have prevailed under nature, and have led to the improvement of the natural
breed or species.  A slight degree of variability leading to some
advantage, however slight, in reiterated deadly contests would suffice for
the work of sexual selection; and it is certain that secondary sexual
characters are eminently variable.  Just as man can give beauty, according
to his standard of taste, to his male poultry, or more strictly can modify
the beauty originally acquired by the parent species, can give to the
Sebright bantam a new and elegant plumage, an erect and peculiar carriage--
so it appears that female birds in a state of nature, have by a long
selection of the more attractive males, added to their beauty or other
attractive qualities.  No doubt this implies powers of discrimination and
taste on the part of the female which will at first appear extremely
improbable; but by the facts to be adduced hereafter, I hope to be able to
shew that the females actually have these powers.  When, however, it is
said that the lower animals have a sense of beauty, it must not be supposed
that such sense is comparable with that of a cultivated man, with his
multiform and complex associated ideas.  A more just comparison would be
between the taste for the beautiful in animals, and that in the lowest
savages, who admire and deck themselves with any brilliant, glittering, or
curious object.

From our ignorance on several points, the precise manner in which sexual
selection acts is somewhat uncertain.  Nevertheless if those naturalists
who already believe in the mutability of species, will read the following
chapters, they will, I think, agree with me, that sexual selection has
played an important part in the history of the organic world.  It is
certain that amongst almost all animals there is a struggle between the
males for the possession of the female.  This fact is so notorious that it
would be superfluous to give instances.  Hence the females have the
opportunity of selecting one out of several males, on the supposition that
their mental capacity suffices for the exertion of a choice.  In many cases
special circumstances tend to make the struggle between the males
particularly severe.  Thus the males of our migratory birds generally
arrive at their places of breeding before the females, so that many males
are ready to contend for each female.  I am informed by Mr. Jenner Weir,
that the bird-catchers assert that this is invariably the case with the
nightingale and blackcap, and with respect to the latter he can himself
confirm the statement.

Mr. Swaysland of Brighton has been in the habit, during the last forty
years, of catching our migratory birds on their first arrival, and he has
never known the females of any species to arrive before their males.
During one spring he shot thirty-nine males of Ray's wagtail (Budytes Raii)
before he saw a single female.  Mr. Gould has ascertained by the dissection
of those snipes which arrive the first in this country, that the males come
before the females.  And the like holds good with most of the migratory
birds of the United States.  (5.  J.A. Allen, on the 'Mammals and Winter
Birds of Florida,' Bulletin of Comparative Zoology, Harvard College, p.
268.)  The majority of the male salmon in our rivers, on coming up from the
sea, are ready to breed before the females.  So it appears to be with frogs
and toads.  Throughout the great class of insects the males almost always
are the first to emerge from the pupal state, so that they generally abound
for a time before any females can be seen.  (6.  Even with those plants in
which the sexes are separate, the male flowers are generally mature before
the female.  As first shewn by C.K. Sprengel, many hermaphrodite plants are
dichogamous; that is, their male and female organs are not ready at the
same time, so that they cannot be self-fertilised.  Now in such flowers,
the pollen is in general matured before the stigma, though there are
exceptional cases in which the female organs are beforehand.)  The cause of
this difference between the males and females in their periods of arrival
and maturity is sufficiently obvious.  Those males which annually first
migrated into any country, or which in the spring were first ready to
breed, or were the most eager, would leave the largest number of offspring;
and these would tend to inherit similar instincts and constitutions.  It
must be borne in mind that it would have been impossible to change very
materially the time of sexual maturity in the females, without at the same
time interfering with the period of the production of the young--a period
which must be determined by the seasons of the year.  On the whole there
can be no doubt that with almost all animals, in which the sexes are
separate, there is a constantly recurrent struggle between the males for
the possession of the females.

Our difficulty in regard to sexual selection lies in understanding how it
is that the males which conquer other males, or those which prove the most
attractive to the females, leave a greater number of offspring to inherit
their superiority than their beaten and less attractive rivals.  Unless
this result does follow, the characters which give to certain males an
advantage over others, could not be perfected and augmented through sexual
selection.  When the sexes exist in exactly equal numbers, the worst-
endowed males will (except where polygamy prevails), ultimately find
females, and leave as many offspring, as well fitted for their general
habits of life, as the best-endowed males.  From various facts and
considerations, I formerly inferred that with most animals, in which
secondary sexual characters are well developed, the males considerably
exceeded the females in number; but this is not by any means always true.
If the males were to the females as two to one, or as three to two, or even
in a somewhat lower ratio, the whole affair would be simple; for the
better-armed or more attractive males would leave the largest number of
offspring.  But after investigating, as far as possible, the numerical
proportion of the sexes, I do not believe that any great inequality in
number commonly exists.  In most cases sexual selection appears to have
been effective in the following manner.

Let us take any species, a bird for instance, and divide the females
inhabiting a district into two equal bodies, the one consisting of the more
vigorous and better-nourished individuals, and the other of the less
vigorous and healthy.  The former, there can be little doubt, would be
ready to breed in the spring before the others; and this is the opinion of
Mr. Jenner Weir, who has carefully attended to the habits of birds during
many years.  There can also be no doubt that the most vigorous, best-
nourished and earliest breeders would on an average succeed in rearing the
largest number of fine offspring.  (7.  Here is excellent evidence on the
character of the offspring from an experienced ornithologist.  Mr. J.A.
Allen, in speaking ('Mammals and Winter Birds of E. Florida,' p. 229) of
the later broods, after the accidental destruction of the first, says, that
these "are found to be smaller and paler-coloured than those hatched
earlier in the season.  In cases where several broods are reared each year,
as a general rule the birds of the earlier broods seem in all respects the
most perfect and vigorous.")  The males, as we have seen, are generally
ready to breed before the females; the strongest, and with some species the
best armed of the males, drive away the weaker; and the former would then
unite with the more vigorous and better-nourished females, because they are
the first to breed.  (8.  Hermann Mueller has come to this same conclusion
with respect to those female bees which are the first to emerge from the
pupa each year.  See his remarkable essay, 'Anwendung der Darwin'schen
Lehre auf Bienen,' 'Verh. d. V. Jahrg.' xxix. p. 45.)  Such vigorous pairs
would surely rear a larger number of offspring than the retarded females,
which would be compelled to unite with the conquered and less powerful
males, supposing the sexes to be numerically equal; and this is all that is
wanted to add, in the course of successive generations, to the size,
strength and courage of the males, or to improve their weapons.

But in very many cases the males which conquer their rivals, do not obtain
possession of the females, independently of the choice of the latter.  The
courtship of animals is by no means so simple and short an affair as might
be thought.  The females are most excited by, or prefer pairing with, the
more ornamented males, or those which are the best songsters, or play the
best antics; but it is obviously probable that they would at the same time
prefer the more vigorous and lively males, and this has in some cases been
confirmed by actual observation.  (9.  With respect to poultry, I have
received information, hereafter to be given, to this effect.  Even with birds,
such as pigeons, which pair for life, the female, as I hear from Mr. Jenner
Weir, will desert her mate if he is injured or grows weak.)  Thus the more
vigorous females, which are the first to breed, will have the choice of
many males; and though they may not always select the strongest or best
armed, they will select those which are vigorous and well armed, and in
other respects the most attractive.  Both sexes, therefore, of such early
pairs would as above explained, have an advantage over others in rearing
offspring; and this apparently has sufficed during a long course of
generations to add not only to the strength and fighting powers of the
males, but likewise to their various ornaments or other attractions.

In the converse and much rarer case of the males selecting particular
females, it is plain that those which were the most vigorous and had
conquered others, would have the freest choice; and it is almost certain
that they would select vigorous as well as attractive females.  Such pairs
would have an advantage in rearing offspring, more especially if the male
had the power to defend the female during the pairing-season as occurs with
some of the higher animals, or aided her in providing for the young.  The
same principles would apply if each sex preferred and selected certain
individuals of the opposite sex; supposing that they selected not only the
more attractive, but likewise the more vigorous individuals.

NUMERICAL PROPORTION OF THE TWO SEXES.

I have remarked that sexual selection would be a simple affair if the males
were considerably more numerous than the females.  Hence I was led to
investigate, as far as I could, the proportions between the two sexes of as
many animals as possible; but the materials are scanty.  I will here give
only a brief abstract of the results, retaining the details for a
supplementary discussion, so as not to interfere with the course of my
argument.  Domesticated animals alone afford the means of ascertaining the
proportional numbers at birth; but no records have been specially kept for
this purpose.  By indirect means, however, I have collected a considerable
body of statistics, from which it appears that with most of our domestic
animals the sexes are nearly equal at birth.  Thus 25,560 births of race-
horses have been recorded during twenty-one years, and the male births were
to the female births as 99.7 to 100.  In greyhounds the inequality is
greater than with any other animal, for out of 6878 births during twelve
years, the male births were to the female as 110.1 to 100.  It is, however,
in some degree doubtful whether it is safe to infer that the proportion
would be the same under natural conditions as under domestication; for
slight and unknown differences in the conditions affect the proportion of
the sexes.  Thus with mankind, the male births in England are as 104.5, in
Russia as 108.9, and with the Jews of Livonia as 120, to 100 female births.
But I shall recur to this curious point of the excess of male births in the
supplement to this chapter.  At the Cape of Good Hope, however, male
children of European extraction have been born during several years in the
proportion of between 90 and 99 to 100 female children.

For our present purpose we are concerned with the proportions of the sexes,
not only at birth, but also at maturity, and this adds another element of
doubt; for it is a well-ascertained fact that with man the number of males
dying before or during birth, and during the first two years of infancy, is
considerably larger than that of females.  So it almost certainly is with
male lambs, and probably with some other animals.  The males of some
species kill one another by fighting; or they drive one another about until
they become greatly emaciated.  They must also be often exposed to various
dangers, whilst wandering about in eager search for the females.  In many
kinds of fish the males are much smaller than the females, and they are
believed often to be devoured by the latter, or by other fishes.  The
females of some birds appear to die earlier than the males; they are also
liable to be destroyed on their nests, or whilst in charge of their young.
With insects the female larvae are often larger than those of the males,
and would consequently be more likely to be devoured.  In some cases the
mature females are less active and less rapid in their movements than the
males, and could not escape so well from danger.  Hence, with animals in a
state of nature, we must rely on mere estimation, in order to judge of the
proportions of the sexes at maturity; and this is but little trustworthy,
except when the inequality is strongly marked.  Nevertheless, as far as a
judgment can be formed, we may conclude from the facts given in the
supplement, that the males of some few mammals, of many birds, of some fish
and insects, are considerably more numerous than the females.

The proportion between the sexes fluctuates slightly during successive
years:  thus with race-horses, for every 100 mares born the stallions
varied from 107.1 in one year to 92.6 in another year, and with greyhounds
from 116.3 to 95.3.  But had larger numbers been tabulated throughout an
area more extensive than England, these fluctuations would probably have
disappeared; and such as they are, would hardly suffice to lead to
effective sexual selection in a state of nature.  Nevertheless, in the
cases of some few wild animals, as shewn in the supplement, the proportions
seem to fluctuate either during different seasons or in different
localities in a sufficient degree to lead to such selection.  For it should
be observed that any advantage, gained during certain years or in certain
localities by those males which were able to conquer their rivals, or were
the most attractive to the females, would probably be transmitted to the
offspring, and would not subsequently be eliminated.  During the succeeding
seasons, when, from the equality of the sexes, every male was able to
procure a female, the stronger or more attractive males previously produced
would still have at least as good a chance of leaving offspring as the
weaker or less attractive.

POLYGAMY.

The practice of polygamy leads to the same results as would follow from an
actual inequality in the number of the sexes; for if each male secures two
or more females, many males cannot pair; and the latter assuredly will be
the weaker or less attractive individuals.  Many mammals and some few birds
are polygamous, but with animals belonging to the lower classes I have
found no evidence of this habit.  The intellectual powers of such animals
are, perhaps, not sufficient to lead them to collect and guard a harem of
females.  That some relation exists between polygamy and the development of
secondary sexual characters, appears nearly certain; and this supports the
view that a numerical preponderance of males would be eminently favourable
to the action of sexual selection.  Nevertheless many animals, which are
strictly monogamous, especially birds, display strongly-marked secondary
sexual characters; whilst some few animals, which are polygamous, do not
have such characters.

We will first briefly run through the mammals, and then turn to birds.  The
gorilla seems to be polygamous, and the male differs considerably from the
female; so it is with some baboons, which live in herds containing twice as
many adult females as males.  In South America the Mycetes caraya presents
well-marked sexual differences, in colour, beard, and vocal organs; and the
male generally lives with two or three wives:  the male of the Cebus
capucinus differs somewhat from the female, and appears to be polygamous.
(10.  On the Gorilla, Savage and Wyman, 'Boston Journal of Natural
History,' vol. v. 1845-47, p. 423.  On Cynocephalus, Brehm, 'Thierleben,'
B. i. 1864, s. 77.  On Mycetes, Rengger, 'Naturgeschichte der Saeugethiere
von Paraguay,' 1830, ss. 14, 20.  On Cebus, Brehm, ibid. s. 108.)  Little
is known on this head with respect to most other monkeys, but some species
are strictly monogamous.  The ruminants are eminently polygamous, and they
present sexual differences more frequently than almost any other group of
mammals; this holds good, especially in their weapons, but also in other
characters.  Most deer, cattle, and sheep are polygamous; as are most
antelopes, though some are monogamous.  Sir Andrew Smith, in speaking of
the antelopes of South Africa, says that in herds of about a dozen there
was rarely more than one mature male.  The Asiatic Antilope saiga appears
to be the most inordinate polygamist in the world; for Pallas (11.  Pallas,
'Spicilegia Zoolog., Fasc.' xii. 1777, p. 29.  Sir Andrew Smith,
'Illustrations of the Zoology of S. Africa,' 1849, pl. 29, on the Kobus.
Owen, in his 'Anatomy of Vertebrates' (vol. iii. 1868, p. 633) gives a
table shewing incidentally which species of antelopes are gregarious.)
states that the male drives away all rivals, and collects a herd of about a
hundred females and kids together; the female is hornless and has softer
hair, but does not otherwise differ much from the male.  The wild horse of
the Falkland Islands and of the Western States of N. America is polygamous,
but, except in his greater size and in the proportions of his body, differs
but little from the mare.  The wild boar presents well-marked sexual
characters, in his great tusks and some other points.  In Europe and in
India he leads a solitary life, except during the breeding-season; but as
is believed by Sir W. Elliot, who has had many opportunities in India of
observing this animal, he consorts at this season with several females.
Whether this holds good in Europe is doubtful, but it is supported by some
evidence.  The adult male Indian elephant, like the boar, passes much of
his time in solitude; but as Dr. Campbell states, when with others, "It is
rare to find more than one male with a whole herd of females"; the larger
males expelling or killing the smaller and weaker ones.  The male differs
from the female in his immense tusks, greater size, strength, and
endurance; so great is the difference in these respects that the males when
caught are valued at one-fifth more than the females.  (12.  Dr. Campbell,
in 'Proc. Zoolog. Soc.' 1869, p. 138.  See also an interesting paper by
Lieut. Johnstone, in 'Proceedings, Asiatic Society of Bengal,' May 1868.)
The sexes of other pachydermatous animals differ very little or not at all,
and, as far as known, they are not polygamists.  Nor have I heard of any
species in the Orders of Cheiroptera, Edentata, Insectivora and Rodents
being polygamous, excepting that amongst the Rodents, the common rat,
according to some rat-catchers, lives with several females.  Nevertheless
the two sexes of some sloths (Edentata) differ in the character and colour
of certain patches of hair on their shoulders.  (13.  Dr. Gray, in 'Annals
and Magazine of Natural History,' 1871, p. 302.)  And many kinds of bats
(Cheiroptera) present well-marked sexual differences, chiefly in the males
possessing odoriferous glands and pouches, and by their being of a lighter
colour.  (14.  See Dr. Dobson's excellent paper in 'Proceedings of the
Zoological Society,' 1873, p. 241.)  In the great order of Rodents, as far
as I can learn, the sexes rarely differ, and when they do so, it is but
slightly in the tint of the fur.

As I hear from Sir Andrew Smith, the lion in South Africa sometimes lives
with a single female, but generally with more, and, in one case, was found
with as many as five females; so that he is polygamous.  As far as I can
discover, he is the only polygamist amongst all the terrestrial Carnivora,
and he alone presents well-marked sexual characters.  If, however, we turn
to the marine Carnivora, as we shall hereafter see, the case is widely
different; for many species of seals offer extraordinary sexual
differences, and they are eminently polygamous.  Thus, according to Peron,
the male sea-elephant of the Southern Ocean always possesses several
females, and the sea-lion of Forster is said to be surrounded by from
twenty to thirty females.  In the North, the male sea-bear of Steller is
accompanied by even a greater number of females.  It is an interesting
fact, as Dr. Gill remarks (15.  'The Eared Seals,' American Naturalist,
vol. iv. Jan. 1871.), that in the monogamous species, "or those living in
small communities, there is little difference in size between the males and
females; in the social species, or rather those of which the males have
harems, the males are vastly larger than the females."

Amongst birds, many species, the sexes of which differ greatly from each
other, are certainly monogamous.  In Great Britain we see well-marked
sexual differences, for instance, in the wild-duck which pairs with a
single female, the common blackbird, and the bullfinch which is said to
pair for life.  I am informed by Mr. Wallace that the like is true of the
Chatterers or Cotingidae of South America, and of many other birds.  In
several groups I have not been able to discover whether the species are
polygamous or monogamous.  Lesson says that birds of paradise, so
remarkable for their sexual differences, are polygamous, but Mr. Wallace
doubts whether he had sufficient evidence.  Mr. Salvin tells me he has been
led to believe that humming-birds are polygamous.  The male widow-bird,
remarkable for his caudal plumes, certainly seems to be a polygamist.  (16.
'The Ibis,' vol. iii. 1861, p. 133, on the Progne Widow-bird.  See also on
the Vidua axillaris, ibid. vol. ii. 1860, p. 211.  On the polygamy of the
Capercailzie and Great Bustard, see L. Lloyd, 'Game Birds of Sweden,' 1867,
pp. 19, and 182.  Montagu and Selby speak of the Black Grouse as polygamous
and of the Red Grouse as monogamous.)  I have been assured by Mr. Jenner
Weir and by others, that it is somewhat common for three starlings to
frequent the same nest; but whether this is a case of polygamy or polyandry
has not been ascertained.

The Gallinaceae exhibit almost as strongly marked sexual differences as
birds of paradise or humming-birds, and many of the species are, as is well
known, polygamous; others being strictly monogamous.  What a contrast is
presented between the sexes of the polygamous peacock or pheasant, and the
monogamous guinea-fowl or partridge!  Many similar cases could be given, as
in the grouse tribe, in which the males of the polygamous capercailzie and
black-cock differ greatly from the females; whilst the sexes of the
monogamous red grouse and ptarmigan differ very little.  In the Cursores,
except amongst the bustards, few species offer strongly-marked sexual
differences, and the great bustard (Otis tarda) is said to be polygamous.
With the Grallatores, extremely few species differ sexually, but the ruff
(Machetes pugnax) affords a marked exception, and this species is believed
by Montagu to be a polygamist.  Hence it appears that amongst birds there
often exists a close relation between polygamy and the development of
strongly-marked sexual differences.  I asked Mr. Bartlett, of the
Zoological Gardens, who has had very large experience with birds, whether
the male tragopan (one of the Gallinaceae) was polygamous, and I was struck
by his answering, "I do not know, but should think so from his splendid
colours."

It deserves notice that the instinct of pairing with a single female is
easily lost under domestication.  The wild-duck is strictly monogamous, the
domestic-duck highly polygamous.  The Rev. W.D. Fox informs me that out of
some half-tamed wild-ducks, on a large pond in his neighbourhood, so many
mallards were shot by the gamekeeper that only one was left for every seven
or eight females; yet unusually large broods were reared.  The guinea-fowl
is strictly monogamous; but Mr. Fox finds that his birds succeed best when
he keeps one cock to two or three hens.  Canary-birds pair in a state of
nature, but the breeders in England successfully put one male to four or
five females.  I have noticed these cases, as rendering it probable that
wild monogamous species might readily become either temporarily or
permanently polygamous.

Too little is known of the habits of reptiles and fishes to enable us to
speak of their marriage arrangements.  The stickle-back (Gasterosteus),
however, is said to be a polygamist (17.  Noel Humphreys, 'River Gardens,'
1857.); and the male during the breeding-season differs conspicuously from
the female.

To sum up on the means through which, as far as we can judge, sexual
selection has led to the development of secondary sexual characters.  It
has been shewn that the largest number of vigorous offspring will be reared
from the pairing of the strongest and best-armed males, victorious in
contests over other males, with the most vigorous and best-nourished
females, which are the first to breed in the spring.  If such females
select the more attractive, and at the same time vigorous males, they will
rear a larger number of offspring than the retarded females, which must
pair with the less vigorous and less attractive males.  So it will be if
the more vigorous males select the more attractive and at the same time
healthy and vigorous females; and this will especially hold good if the
male defends the female, and aids in providing food for the young.  The
advantage thus gained by the more vigorous pairs in rearing a larger number
of offspring has apparently sufficed to render sexual selection efficient.
But a large numerical preponderance of males over females will be still
more efficient; whether the preponderance is only occasional and local, or
permanent; whether it occurs at birth, or afterwards from the greater
destruction of the females; or whether it indirectly follows from the
practice of polygamy.

THE MALE GENERALLY MORE MODIFIED THAN THE FEMALE.

Throughout the animal kingdom, when the sexes differ in external
appearance, it is, with rare exceptions, the male which has been the more
modified; for, generally, the female retains a closer resemblance to the
young of her own species, and to other adult members of the same group.
The cause of this seems to lie in the males of almost all animals having
stronger passions than the females.  Hence it is the males that fight
together and sedulously display their charms before the females; and the
victors transmit their superiority to their male offspring.  Why both sexes
do not thus acquire the characters of their fathers, will be considered
hereafter.  That the males of all mammals eagerly pursue the females is
notorious to every one.  So it is with birds; but many cock birds do not so
much pursue the hen, as display their plumage, perform strange antics, and
pour forth their song in her presence.  The male in the few fish observed
seems much more eager than the female; and the same is true of alligators,
and apparently of Batrachians.  Throughout the enormous class of insects,
as Kirby remarks, "the law is that the male shall seek the female."  (18.
Kirby and Spence, 'Introduction to Entomology,' vol. iii. 1826, p. 342.)
Two good authorities, Mr. Blackwall and Mr. C. Spence Bate, tell me that
the males of spiders and crustaceans are more active and more erratic in
their habits than the females.  When the organs of sense or locomotion are
present in the one sex of insects and crustaceans and absent in the other,
or when, as is frequently the case, they are more highly developed in the
one than in the other, it is, as far as I can discover, almost invariably
the male which retains such organs, or has them most developed; and this
shews that the male is the more active member in the courtship of the
sexes.  (19.  One parasitic Hymenopterous insect (Westwood, 'Modern Class.
of Insects,' vol. ii. p. 160) forms an exception to the rule, as the male
has rudimentary wings, and never quits the cell in which it is born, whilst
the female has well-developed wings.  Audouin believes that the females of
this species are impregnated by the males which are born in the same cells
with them; but it is much more probable that the females visit other cells,
so that close inter-breeding is thus avoided.  We shall hereafter meet in
various classes, with a few exceptional cases, in which the female, instead
of the male, is the seeker and wooer.)

The female, on the other hand, with the rarest exceptions, is less eager
than the male.  As the illustrious Hunter (20.  'Essays and Observations,'
edited by Owen, vol. i. 1861, p. 194.) long ago observed, she generally
"requires to be courted;" she is coy, and may often be seen endeavouring
for a long time to escape from the male.  Every observer of the habits of
animals will be able to call to mind instances of this kind.  It is shewn
by various facts, given hereafter, and by the results fairly attributable
to sexual selection, that the female, though comparatively passive,
generally exerts some choice and accepts one male in preference to others.
Or she may accept, as appearances would sometimes lead us to believe, not
the male which is the most attractive to her, but the one which is the
least distasteful.  The exertion of some choice on the part of the female
seems a law almost as general as the eagerness of the male.

We are naturally led to enquire why the male, in so many and such distinct
classes, has become more eager than the female, so that he searches for
her, and plays the more active part in courtship.  It would be no advantage
and some loss of power if each sex searched for the other; but why should
the male almost always be the seeker?  The ovules of plants after
fertilisation have to be nourished for a time; hence the pollen is
necessarily brought to the female organs--being placed on the stigma, by
means of insects or the wind, or by the spontaneous movements of the
stamens; and in the Algae, etc., by the locomotive power of the
antherozooids.  With lowly-organised aquatic animals, permanently affixed
to the same spot and having their sexes separate, the male element is
invariably brought to the female; and of this we can see the reason, for
even if the ova were detached before fertilisation, and did not require
subsequent nourishment or protection, there would yet be greater difficulty
in transporting them than the male element, because, being larger than the
latter, they are produced in far smaller numbers.  So that many of the
lower animals are, in this respect, analogous with plants.  (21.  Prof.
Sachs ('Lehrbuch der Botanik,' 1870, S. 633) in speaking of the male and
female reproductive cells, remarks, "verhaelt sich die eine bei der
Vereinigung activ,...die andere erscheint bei der Vereinigung passiv.")
The males of affixed and aquatic animals having been led to emit their
fertilising element in this way, it is natural that any of their
descendants, which rose in the scale and became locomotive, should retain
the same habit; and they would approach the female as closely as possible,
in order not to risk the loss of the fertilising element in a long passage
of it through the water.  With some few of the lower animals, the females
alone are fixed, and the males of these must be the seekers.  But it is
difficult to understand why the males of species, of which the progenitors
were primordially free, should invariably have acquired the habit of
approaching the females, instead of being approached by them.  But in all
cases, in order that the males should seek efficiently, it would be
necessary that they should be endowed with strong passions; and the
acquirement of such passions would naturally follow from the more eager
leaving a larger number of offspring than the less eager.

The great eagerness of the males has thus indirectly led to their much more
frequently developing secondary sexual characters than the females.  But
the development of such characters would be much aided, if the males were
more liable to vary than the females--as I concluded they were--after a
long study of domesticated animals.  Von Nathusius, who has had very wide
experience, is strongly of the same opinion.  (22.  'Vortraege uber
Viehzucht,' 1872, p. 63.)  Good evidence also in favour of this conclusion
can be produced by a comparison of the two sexes in mankind.  During the
Novara Expedition (23.  'Reise der Novara:  Anthropolog. Theil,' 1867, ss.
216-269.  The results were calculated by Dr. Weisbach from measurements
made by Drs. K. Scherzer and Schwarz.  On the greater variability of the
males of domesticated animals, see my 'Variation of Animals and Plants
under Domestication,' vol. ii. 1868, p. 75.) a vast number of measurements
was made of various parts of the body in different races, and the men were
found in almost every case to present a greater range of variation than the
women; but I shall have to recur to this subject in a future chapter.  Mr.
J. Wood (24.  'Proceedings of the Royal Society,' vol. xvi. July 1868, pp.
519 and 524.), who has carefully attended to the variation of the muscles
in man, puts in italics the conclusion that "the greatest number of
abnormalities in each subject is found in the males."  He had previously
remarked that "altogether in 102 subjects, the varieties of redundancy were
found to be half as many again as in females, contrasting widely with the
greater frequency of deficiency in females before described."  Professor
Macalister likewise remarks (25.  'Proc. Royal Irish Academy,' vol. x.
1868, p. 123.) that variations in the muscles "are probably more common in
males than females."  Certain muscles which are not normally present in
mankind are also more frequently developed in the male than in the female
sex, although exceptions to this rule are said to occur.  Dr. Burt Wilder
(26.  'Massachusetts Medical Society,' vol. ii. No. 3, 1868, p. 9.) has
tabulated the cases of 152 individuals with supernumerary digits, of which
86 were males, and 39, or less than half, females, the remaining 27 being
of unknown sex.  It should not, however, be overlooked that women would
more frequently endeavour to conceal a deformity of this kind than men.
Again, Dr. L. Meyer asserts that the ears of man are more variable in form
than those of a woman.  (27.  'Archiv fur Path. Anat. und Phys.' 1871, p.
488.)  Lastly the temperature is more variable in man than in woman.  (28.
The conclusions recently arrived at by Dr. J. Stockton Hough, on the
temperature of man, are given in the 'Pop. Sci. Review,' Jan. 1st, 1874, p.
97.)

The cause of the greater general variability in the male sex, than in the
female is unknown, except in so far as secondary sexual characters are
extraordinarily variable, and are usually confined to the males; and, as we
shall presently see, this fact is, to a certain extent, intelligible.
Through the action of sexual and natural selection male animals have been
rendered in very many instances widely different from their females; but
independently of selection the two sexes, from differing constitutionally,
tend to vary in a somewhat different manner.  The female has to expend much
organic matter in the formation of her ova, whereas the male expends much
force in fierce contests with his rivals, in wandering about in search of
the female, in exerting his voice, pouring out odoriferous secretions,
etc.:  and this expenditure is generally concentrated within a short
period.  The great vigour of the male during the season of love seems often
to intensify his colours, independently of any marked difference from the
female.  (29.  Prof. Mantegazza is inclined to believe ('Lettera a Carlo
Darwin,' 'Archivio per l'Anthropologia,' 1871, p. 306) that the bright
colours, common in so many male animals, are due to the presence and
retention by them of the spermatic fluid; but this can hardly be the case;
for many male birds, for instance young pheasants, become brightly coloured
in the autumn of their first year.)  In mankind, and even as low down in
the organic scale as in the Lepidoptera, the temperature of the body is
higher in the male than in the female, accompanied in the case of man by a
slower pulse.  (30.  For mankind, see Dr. J. Stockton Hough, whose
conclusions are given in the 'Popular Science Review,' 1874, p. 97.  See
Girard's observations on the Lepidoptera, as given in the 'Zoological
Record,' 1869, p. 347.)  On the whole the expenditure of matter and force
by the two sexes is probably nearly equal, though effected in very
different ways and at different rates.

From the causes just specified the two sexes can hardly fail to differ
somewhat in constitution, at least during the breeding-season; and,
although they may be subjected to exactly the same conditions, they will
tend to vary in a different manner.  If such variations are of no service
to either sex, they will not be accumulated and increased by sexual or
natural selection.  Nevertheless, they may become permanent if the exciting
cause acts permanently; and in accordance with a frequent form of
inheritance they may be transmitted to that sex alone in which they first
appeared.  In this case the two sexes will come to present permanent, yet
unimportant, differences of character.  For instance, Mr. Allen shews that
with a large number of birds inhabiting the northern and southern United
States, the specimens from the south are darker-coloured than those from
the north; and this seems to be the direct result of the difference in
temperature, light, etc., between the two regions.  Now, in some few cases,
the two sexes of the same species appear to have been differently affected;
in the Agelaeus phoeniceus the males have had their colours greatly
intensified in the south; whereas with Cardinalis virginianus it is the
females which have been thus affected; with Quiscalus major the females
have been rendered extremely variable in tint, whilst the males remain
nearly uniform.  (31.  'Mammals and Birds of E. Florida,' pp. 234, 280,
295.)

A few exceptional cases occur in various classes of animals, in which the
females instead of the males have acquired well pronounced secondary sexual
characters, such as brighter colours, greater size, strength, or pugnacity.
With birds there has sometimes been a complete transposition of the
ordinary characters proper to each sex; the females having become the more
eager in courtship, the males remaining comparatively passive, but
apparently selecting the more attractive females, as we may infer from the
results.  Certain hen birds have thus been rendered more highly coloured or
otherwise ornamented, as well as more powerful and pugnacious than the
cocks; these characters being transmitted to the female offspring alone.

It may be suggested that in some cases a double process of selection has
been carried on; that the males have selected the more attractive females,
and the latter the more attractive males.  This process, however, though it
might lead to the modification of both sexes, would not make the one sex
different from the other, unless indeed their tastes for the beautiful
differed; but this is a supposition too improbable to be worth considering
in the case of any animal, excepting man.  There are, however, many animals
in which the sexes resemble each other, both being furnished with the same
ornaments, which analogy would lead us to attribute to the agency of sexual
selection.  In such cases it may be suggested with more plausibility, that
there has been a double or mutual process of sexual selection; the more
vigorous and precocious females selecting the more attractive and vigorous
males, the latter rejecting all except the more attractive females.  But
from what we know of the habits of animals, this view is hardly probable,
for the male is generally eager to pair with any female.  It is more
probable that the ornaments common to both sexes were acquired by one sex,
generally the male, and then transmitted to the offspring of both sexes.
If, indeed, during a lengthened period the males of any species were
greatly to exceed the females in number, and then during another lengthened
period, but under different conditions, the reverse were to occur, a
double, but not simultaneous, process of sexual selection might easily be
carried on, by which the two sexes might be rendered widely different.

We shall hereafter see that many animals exist, of which neither sex is
brilliantly coloured or provided with special ornaments, and yet the
members of both sexes or of one alone have probably acquired simple
colours, such as white or black, through sexual selection.  The absence of
bright tints or other ornaments may be the result of variations of the
right kind never having occurred, or of the animals themselves having
preferred plain black or white.  Obscure tints have often been developed
through natural selection for the sake of protection, and the acquirement
through sexual selection of conspicuous colours, appears to have been
sometimes checked from the danger thus incurred.  But in other cases the
males during long ages may have struggled together for the possession of
the females, and yet no effect will have been produced, unless a larger
number of offspring were left by the more successful males to inherit their
superiority, than by the less successful:  and this, as previously shewn,
depends on many complex contingencies.

Sexual selection acts in a less rigorous manner than natural selection.
The latter produces its effects by the life or death at all ages of the
more or less successful individuals.  Death, indeed, not rarely ensues from
the conflicts of rival males.  But generally the less successful male
merely fails to obtain a female, or obtains a retarded and less vigorous
female later in the season, or, if polygamous, obtains fewer females; so
that they leave fewer, less vigorous, or no offspring.  In regard to
structures acquired through ordinary or natural selection, there is in most
cases, as long as the conditions of life remain the same, a limit to the
amount of advantageous modification in relation to certain special
purposes; but in regard to structures adapted to make one male victorious
over another, either in fighting or in charming the female, there is no
definite limit to the amount of advantageous modification; so that as long
as the proper variations arise the work of sexual selection will go on.
This circumstance may partly account for the frequent and extraordinary
amount of variability presented by secondary sexual characters.
Nevertheless, natural selection will determine that such characters shall
not be acquired by the victorious males, if they would be highly injurious,
either by expending too much of their vital powers, or by exposing them to
any great danger.  The development, however, of certain structures--of the
horns, for instance, in certain stags--has been carried to a wonderful
extreme; and in some cases to an extreme which, as far as the general
conditions of life are concerned, must be slightly injurious to the male.
From this fact we learn that the advantages which favoured males derive
from conquering other males in battle or courtship, and thus leaving a
numerous progeny, are in the long run greater than those derived from
rather more perfect adaptation to their conditions of life.  We shall
further see, and it could never have been anticipated, that the power to
charm the female has sometimes been more important than the power to
conquer other males in battle.

LAWS OF INHERITANCE.

In order to understand how sexual selection has acted on many animals of
many classes, and in the course of ages has produced a conspicuous result,
it is necessary to bear in mind the laws of inheritance, as far as they are
known.  Two distinct elements are included under the term "inheritance"--
the transmission, and the development of characters; but as these generally
go together, the distinction is often overlooked.  We see this distinction
in those characters which are transmitted through the early years of life,
but are developed only at maturity or during old age.  We see the same
distinction more clearly with secondary sexual characters, for these are
transmitted through both sexes, though developed in one alone.  That they
are present in both sexes, is manifest when two species, having strongly-
marked sexual characters, are crossed, for each transmits the characters
proper to its own male and female sex to the hybrid offspring of either
sex.  The same fact is likewise manifest, when characters proper to the
male are occasionally developed in the female when she grows old or becomes
diseased, as, for instance, when the common hen assumes the flowing tail-
feathers, hackles, comb, spurs, voice, and even pugnacity of the cock.
Conversely, the same thing is evident, more or less plainly, with castrated
males.  Again, independently of old age or disease, characters are
occasionally transferred from the male to the female, as when, in certain
breeds of the fowl, spurs regularly appear in the young and healthy
females.  But in truth they are simply developed in the female; for in
every breed each detail in the structure of the spur is transmitted through
the female to her male offspring.  Many cases will hereafter be given,
where the female exhibits, more or less perfectly, characters proper to the
male, in whom they must have been first developed, and then transferred to
the female.  The converse case of the first development of characters in
the female and of transference to the male, is less frequent; it will
therefore be well to give one striking instance.  With bees the pollen-
collecting apparatus is used by the female alone for gathering pollen for
the larvae, yet in most of the species it is partially developed in the
males to whom it is quite useless, and it is perfectly developed in the
males of Bombus or the humble-bee.  (32.  H. Muller, 'Anwendung der
Darwin'schen Lehre,' etc., Verh. d. n. V. Jahrg., xxix. p. 42.)  As not a
single other Hymenopterous insect, not even the wasp, which is closely
allied to the bee, is provided with a pollen-collecting apparatus, we have
no grounds for supposing that male bees primordially collected pollen as
well as the females; although we have some reason to suspect that male
mammals primordially suckled their young as well as the females.  Lastly,
in all cases of reversion, characters are transmitted through two, three,
or many more generations, and are then developed under certain unknown
favourable conditions.  This important distinction between transmission and
development will be best kept in mind by the aid of the hypothesis of
pangenesis.  According to this hypothesis, every unit or cell of the body
throws off gemmules or undeveloped atoms, which are transmitted to the
offspring of both sexes, and are multiplied by self-division.  They may
remain undeveloped during the early years of life or during successive
generations; and their development into units or cells, like those from
which they were derived, depends on their affinity for, and union with
other units or cells previously developed in the due order of growth.

INHERITANCE AT CORRESPONDING PERIODS OF LIFE.

This tendency is well established.  A new character, appearing in a young
animal, whether it lasts throughout life or is only transient, will, in
general, reappear in the offspring at the same age and last for the same
time.  If, on the other hand, a new character appears at maturity, or even
during old age, it tends to reappear in the offspring at the same advanced
age.  When deviations from this rule occur, the transmitted characters much
oftener appear before, than after the corresponding age.  As I have dwelt
on this subject sufficiently in another work (33.  The 'Variation of
Animals and Plants under Domestication,' vol. ii. 1868, p. 75.  In the last
chapter but one, the provisional hypothesis of pangenesis, above alluded
to, is fully explained.), I will here merely give two or three instances,
for the sake of recalling the subject to the reader's mind.  In several
breeds of the Fowl, the down-covered chickens, the young birds in their
first true plumage, and the adults differ greatly from one another, as well
as from their common parent-form, the Gallus bankiva; and these characters
are faithfully transmitted by each breed to their offspring at the
corresponding periods of life.  For instance, the chickens of spangled
Hamburgs, whilst covered with down, have a few dark spots on the head and
rump, but are not striped longitudinally, as in many other breeds; in their
first true plumage, "they are beautifully pencilled," that is each feather
is transversely marked by numerous dark bars; but in their second plumage
the feathers all become spangled or tipped with a dark round spot.  (34.
These facts are given on the high authority of a great breeder, Mr. Teebay;
see Tegetmeier's 'Poultry Book,' 1868, p. 158.  On the characters of
chickens of different breeds, and on the breeds of the pigeon, alluded to
in the following paragraph, see 'Variation of Animals,' etc., vol. i. pp.
160, 249; vol. ii. p. 77.)  Hence in this breed variations have occurred
at, and been transmitted to, three distinct periods of life.  The Pigeon
offers a more remarkable case, because the aboriginal parent species does
not undergo any change of plumage with advancing age, excepting that at
maturity the breast becomes more iridescent; yet there are breeds which do
not acquire their characteristic colours until they have moulted two,
three, or four times; and these modifications of plumage are regularly
transmitted.

INHERITANCE AT CORRESPONDING SEASONS OF THE YEAR.

With animals in a state of nature, innumerable instances occur of
characters appearing periodically at different seasons.  We see this in the
horns of the stag, and in the fur of Arctic animals which becomes thick and
white during the winter.  Many birds acquire bright colours and other
decorations during the breeding-season alone.  Pallas states (35.  'Novae
species Quadrupedum e Glirium ordine,' 1778, p. 7.  On the transmission of
colour by the horse, see 'Variation of Animals and Plants under
Domestication,' vol. i. p. 51.  Also vol. ii. p. 71, for a general
discussion on 'Inheritance as limited by Sex.'), that in Siberia domestic
cattle and horses become lighter-coloured during the winter; and I have
myself observed, and heard of similar strongly marked changes of colour,
that is, from brownish cream-colour or reddish-brown to a perfect white, in
several ponies in England.  Although I do not know that this tendency to
change the colour of the coat during different seasons is transmitted, yet
it probably is so, as all shades of colour are strongly inherited by the
horse.  Nor is this form of inheritance, as limited by the seasons, more
remarkable than its limitation by age or sex.

INHERITANCE AS LIMITED BY SEX.

The equal transmission of characters to both sexes is the commonest form of
inheritance, at least with those animals which do not present strongly-
marked sexual differences, and indeed with many of these.  But characters
are somewhat commonly transferred exclusively to that sex, in which they
first appear.  Ample evidence on this head has been advanced in my work on
'Variation under Domestication,' but a few instances may here be given.
There are breeds of the sheep and goat, in which the horns of the male
differ greatly in shape from those of the female; and these differences,
acquired under domestication, are regularly transmitted to the same sex.
As a rule, it is the females alone in cats which are tortoise-shell, the
corresponding colour in the males being rusty-red.  With most breeds of the
fowl, the characters proper to each sex are transmitted to the same sex
alone.  So general is this form of transmission that it is an anomaly when
variations in certain breeds are transmitted equally to both sexes.  There
are also certain sub-breeds of the fowl in which the males can hardly be
distinguished from one another, whilst the females differ considerably in
colour.  The sexes of the pigeon in the parent-species do not differ in any
external character; nevertheless, in certain domesticated breeds the male
is coloured differently from the female.  (36.  Dr. Chapuis, 'Le Pigeon
Voyageur Belge,' 1865, p. 87.  Boitard et Corbie, 'Les Pigeons de Voliere,'
etc., 1824, p. 173.  See, also, on similar differences in certain breeds at
Modena, 'Le variazioni dei Colombi domestici,' del Paolo Bonizzi, 1873.)
The wattle in the English Carrier pigeon, and the crop in the Pouter, are
more highly developed in the male than in the female; and although these
characters have been gained through long-continued selection by man, the
slight differences between the sexes are wholly due to the form of
inheritance which has prevailed; for they have arisen, not from, but rather
in opposition to, the wish of the breeder.


Most of our domestic races have been formed by the accumulation of many
slight variations; and as some of the successive steps have been
transmitted to one sex alone, and some to both sexes, we find in the
different breeds of the same species all gradations between great sexual
dissimilarity and complete similarity.  Instances have already been given
with the breeds of the fowl and pigeon, and under nature analogous cases
are common.  With animals under domestication, but whether in nature I will
not venture to say, one sex may lose characters proper to it, and may thus
come somewhat to resemble the opposite sex; for instance, the males of some
breeds of the fowl have lost their masculine tail-plumes and hackles.  On
the other hand, the differences between the sexes may be increased under
domestication, as with merino sheep, in which the ewes have lost their
horns.  Again, characters proper to one sex may suddenly appear in the
other sex; as in those sub-breeds of the fowl in which the hens acquire
spurs whilst young; or, as in certain Polish sub-breeds, in which the
females, as there is reason to believe, originally acquired a crest, and
subsequently transferred it to the males.  All these cases are intelligible
on the hypothesis of pangenesis; for they depend on the gemmules of certain
parts, although present in both sexes, becoming, through the influence of
domestication, either dormant or developed in either sex.

There is one difficult question which it will be convenient to defer to a
future chapter; namely, whether a character at first developed in both
sexes, could through selection be limited in its development to one sex
alone.  If, for instance, a breeder observed that some of his pigeons (of
which the characters are usually transferred in an equal degree to both
sexes) varied into pale blue, could he by long-continued selection make a
breed, in which the males alone should be of this tint, whilst the females
remained unchanged?  I will here only say, that this, though perhaps not
impossible, would be extremely difficult; for the natural result of
breeding from the pale-blue males would be to change the whole stock of
both sexes to this tint.  If, however, variations of the desired tint
appeared, which were from the first limited in their development to the
male sex, there would not be the least difficulty in making a breed with
the two sexes of a different colour, as indeed has been effected with a
Belgian breed, in which the males alone are streaked with black.  In a
similar manner, if any variation appeared in a female pigeon, which was
from the first sexually limited in its development to the females, it would
be easy to make a breed with the females alone thus characterised; but if
the variation was not thus originally limited, the process would be
extremely difficult, perhaps impossible.  (37.  Since the publication of
the first edition of this work, it has been highly satisfactory to me to
find the following remarks (the 'Field,' Sept. 1872) from so experienced a
breeder as Mr. Tegetmeier.  After describing some curious cases in pigeons,
of the transmission of colour by one sex alone, and the formation of a sub-
breed with this character, he says:  "It is a singular circumstance that
Mr. Darwin should have suggested the possibility of modifying the sexual
colours of birds by a course of artificial selection.  When he did so, he
was in ignorance of these facts that I have related; but it is remarkable
how very closely he suggested the right method of procedure.")

ON THE RELATION BETWEEN THE PERIOD OF DEVELOPMENT OF A CHARACTER AND ITS
TRANSMISSION TO ONE SEX OR TO BOTH SEXES.

Why certain characters should be inherited by both sexes, and other
characters by one sex alone, namely by that sex in which the character
first appeared, is in most cases quite unknown.  We cannot even conjecture
why with certain sub-breeds of the pigeon, black striae, though transmitted
through the female, should be developed in the male alone, whilst every
other character is equally transferred to both sexes.  Why, again, with
cats, the tortoise-shell colour should, with rare exceptions, be developed
in the female alone.  The very same character, such as deficient or
supernumerary digits, colour-blindness, etc., may with mankind be inherited
by the males alone of one family, and in another family by the females
alone, though in both cases transmitted through the opposite as well as
through the same sex.  (38.  References are given in my 'Variation of
Animals and Plants under Domestication,' vol. ii. p. 72.)  Although we are
thus ignorant, the two following rules seem often to hold good--that
variations which first appear in either sex at a late period of life, tend
to be developed in the same sex alone; whilst variations which first appear
early in life in either sex tend to be developed in both sexes.  I am,
however, far from supposing that this is the sole determining cause.  As I
have not elsewhere discussed this subject, and it has an important bearing
on sexual selection, I must here enter into lengthy and somewhat intricate
details.

It is in itself probable that any character appearing at an early age would
tend to be inherited equally by both sexes, for the sexes do not differ
much in constitution before the power of reproduction is gained.  On the
other hand, after this power has been gained and the sexes have come to
differ in constitution, the gemmules (if I may again use the language of
pangenesis) which are cast off from each varying part in the one sex would
be much more likely to possess the proper affinities for uniting with the
tissues of the same sex, and thus becoming developed, than with those of
the opposite sex.

I was first led to infer that a relation of this kind exists, from the fact
that whenever and in whatever manner the adult male differs from the adult
female, he differs in the same manner from the young of both sexes.  The
generality of this fact is quite remarkable:  it holds good with almost all
mammals, birds, amphibians, and fishes; also with many crustaceans,
spiders, and some few insects, such as certain orthoptera and libellulae.
In all these cases the variations, through the accumulation of which the
male acquired his proper masculine characters, must have occurred at a
somewhat late period of life; otherwise the young males would have been
similarly characterised; and conformably with our rule, the variations are
transmitted to and developed in the adult males alone.  When, on the other
hand, the adult male closely resembles the young of both sexes (these, with
rare exceptions, being alike), he generally resembles the adult female; and
in most of these cases the variations through which the young and old
acquired their present characters, probably occurred, according to our
rule, during youth.  But there is here room for doubt, for characters are
sometimes transferred to the offspring at an earlier age than that at which
they first appeared in the parents, so that the parents may have varied
when adult, and have transferred their characters to their offspring whilst
young.  There are, moreover, many animals, in which the two sexes closely
resemble each other, and yet both differ from their young:  and here the
characters of the adults must have been acquired late in life;
nevertheless, these characters, in apparent contradiction to our rule, are
transferred to both sexes.  We must not however, overlook the possibility
or even probability of successive variations of the same nature occurring,
under exposure to similar conditions, simultaneously in both sexes at a
rather late period of life; and in this case the variations would be
transferred to the offspring of both sexes at a corresponding late age; and
there would then be no real contradiction to the rule that variations
occurring late in life are transferred exclusively to the sex in which they
first appeared.  This latter rule seems to hold true more generally than
the second one, namely, that variations which occur in either sex early in
life tend to be transferred to both sexes.  As it was obviously impossible
even to estimate in how large a number of cases throughout the animal
kingdom these two propositions held good, it occurred to me to investigate
some striking or crucial instances, and to rely on the result.

An excellent case for investigation is afforded by the Deer family.  In all
the species, but one, the horns are developed only in the males, though
certainly transmitted through the females, and capable of abnormal
development in them.  In the reindeer, on the other hand, the female is
provided with horns; so that in this species, the horns ought, according to
our rule, to appear early in life, long before the two sexes are mature and
have come to differ much in constitution.  In all the other species the
horns ought to appear later in life, which would lead to their development
in that sex alone, in which they first appeared in the progenitor of the
whole Family.  Now in seven species, belonging to distinct sections of the
family and inhabiting different regions, in which the stags alone bear
horns, I find that the horns first appear at periods, varying from nine
months after birth in the roebuck, to ten, twelve or even more months in
the stags of the six other and larger species.  (39.  I am much obliged to
Mr. Cupples for having made enquiries for me in regard to the Roebuck and
Red Deer of Scotland from Mr. Robertson, the experienced head-forester to
the Marquis of Breadalbane.  In regard to Fallow-deer, I have to thank Mr.
Eyton and others for information.  For the Cervus alces of N. America, see
'Land and Water,' 1868, pp. 221 and 254; and for the C. Virginianus and
strongyloceros of the same continent, see J.D. Caton, in 'Ottawa Acad. of
Nat. Sc.' 1868, p. 13.  For Cervus Eldi of Pegu, see Lieut. Beaven,
'Proccedings of the Zoological Society,' 1867, p. 762.)  But with the
reindeer the case is widely different; for, as I hear from Prof. Nilsson,
who kindly made special enquiries for me in Lapland, the horns appear in
the young animals within four or five weeks after birth, and at the same
time in both sexes.  So that here we have a structure, developed at a most
unusually early age in one species of the family, and likewise common to
both sexes in this one species alone.

In several kinds of antelopes, only the males are provided with horns,
whilst in the greater number both sexes bear horns.  With respect to the
period of development, Mr. Blyth informs me that there was at one time in
the Zoological Gardens a young koodoo (Ant. strepsiceros), of which the
males alone are horned, and also the young of a closely-allied species, the
eland (Ant. oreas), in which both sexes are horned.  Now it is in strict
conformity with our rule, that in the young male koodoo, although ten
months old, the horns were remarkably small, considering the size
ultimately attained by them; whilst in the young male eland, although only
three months old, the horns were already very much larger than in the
koodoo.  It is also a noticeable fact that in the prong-horned antelope
(40.  Antilocapra Americana.  I have to thank Dr. Canfield for information
with respect to the horns of the female:  see also his paper in
'Proceedings of the Zoological Society,' 1866, p. 109.  Also Owen, 'Anatomy
of Vertebrates,' vol. iii. p. 627), only a few of the females, about one in
five, have horns, and these are in a rudimentary state, though sometimes
above four inches long:  so that as far as concerns the possession of horns
by the males alone, this species is in an intermediate condition, and the
horns do not appear until about five or six months after birth.  Therefore
in comparison with what little we know of the development of the horns in
other antelopes, and from what we do know with respect to the horns of
deer, cattle, etc., those of the prong-horned antelope appear at an
intermediate period of life,--that is, not very early, as in cattle and
sheep, nor very late, as in the larger deer and antelopes.  The horns of
sheep, goats, and cattle, which are well developed in both sexes, though
not quite equal in size, can be felt, or even seen, at birth or soon
afterwards.  (41.  I have been assured that the horns of the sheep in North
Wales can always be felt, and are sometimes even an inch in length, at
birth.  Youatt says ('Cattle,' 1834, p. 277), that the prominence of the
frontal bone in cattle penetrates the cutis at birth, and that the horny
matter is soon formed over it.)  Our rule, however, seems to fail in some
breeds of sheep, for instance merinos, in which the rams alone are horned;
for I cannot find on enquiry (42.  I am greatly indebted to Prof. Victor
Carus for having made enquiries for me, from the highest authorities, with
respect to the merino sheep of Saxony.  On the Guinea coast of Africa there
is, however, a breed of sheep in which, as with merinos, the rams alone
bear horns; and Mr. Winwood Reade informs me that in one case observed by
him, a young ram, born on Feb. 10th, first shewed horns on March 6th, so
that in this instance, in conformity with rule, the development of the
horns occurred at a later period of life than in Welsh sheep, in which both
sexes are horned.), that the horns are developed later in life in this
breed than in ordinary sheep in which both sexes are horned.  But with
domesticated sheep the presence or absence of horns is not a firmly fixed
character; for a certain proportion of the merino ewes bear small horns,
and some of the rams are hornless; and in most breeds hornless ewes are
occasionally produced.

Dr. W. Marshall has lately made a special study of the protuberances so
common on the heads of birds (43.  'Ueber die knochernen Schaedelhoecker der
Voegel,' in the 'Niederland. Archiv fur Zoologie,' B.i. Heft 2, 1872.), and
he comes to the following conclusion:--that with those species in which
they are confined to the males, they are developed late in life; whereas
with those species in which they are common to the two sexes, they are
developed at a very early period.  This is certainly a striking
confirmation of my two laws of inheritance.

In most of the species of the splendid family of the Pheasants, the males
differ conspicuously from the females, and they acquire their ornaments at
a rather late period of life.  The eared pheasant (Crossoptilon auritum),
however, offers a remarkable exception, for both sexes possess the fine
caudal plumes, the large ear-tufts and the crimson velvet about the head; I
find that all these characters appear very early in life in accordance with
rule.  The adult male can, however, be distinguished from the adult female
by the presence of spurs; and conformably with our rule, these do not begin
to be developed before the age of six months, as I am assured by Mr.
Bartlett, and even at this age, the two sexes can hardly be distinguished.
(44.  In the common peacock (Pavo cristatus) the male alone possesses
spurs, whilst both sexes of the Java Peacock (P. muticus) offer the unusual
case of being furnished with spurs.  Hence I fully expected that in the
latter species they would have been developed earlier in life than in the
common peacock; but M. Hegt of Amsterdam informs me, that with young birds
of the previous year, of both species, compared on April 23rd, 1869, there
was no difference in the development of the spurs.  The spurs, however,
were as yet represented merely by slight knobs or elevations.  I presume
that I should have been informed if any difference in the rate of
development had been observed subsequently.)  The male and female Peacock
differ conspicuously from each other in almost every part of their plumage,
except in the elegant head-crest, which is common to both sexes; and this
is developed very early in life, long before the other ornaments, which are
confined to the male.  The wild-duck offers an analogous case, for the
beautiful green speculum on the wings is common to both sexes, though
duller and somewhat smaller in the female, and it is developed early in
life, whilst the curled tail-feathers and other ornaments of the male are
developed later.  (45.  In some other species of the Duck family the
speculum differs in a greater degree in the two sexes; but I have not been
able to discover whether its full development occurs later in life in the
males of such species, than in the male of the common duck, as ought to be
the case according to our rule.  With the allied Mergus cucullatus we have,
however, a case of this kind:  the two sexes differ conspicuously in
general plumage, and to a considerable degree in the speculum, which is
pure white in the male and greyish-white in the female.  Now the young
males at first entirely resemble the females, and have a greyish-white
speculum, which becomes pure white at an earlier age than that at which the
adult male acquires his other and more strongly-marked sexual differences:
see Audubon, 'Ornithological Biography,' vol. iii. 1835, pp. 249-250.)
Between such extreme cases of close sexual resemblance and wide
dissimilarity, as those of the Crossoptilon and peacock, many intermediate
ones could be given, in which the characters follow our two rules in their
order of development.

As most insects emerge from the pupal state in a mature condition, it is
doubtful whether the period of development can determine the transference
of their characters to one or to both sexes.  But we do not know that the
coloured scales, for instance, in two species of butterflies, in one of
which the sexes differ in colour, whilst in the other they are alike, are
developed at the same relative age in the cocoon.  Nor do we know whether
all the scales are simultaneously developed on the wings of the same
species of butterfly, in which certain coloured marks are confined to one
sex, whilst others are common to both sexes.  A difference of this kind in
the period of development is not so improbable as it may at first appear;
for with the Orthoptera, which assume their adult state, not by a single
metamorphosis, but by a succession of moults, the young males of some
species at first resemble the females, and acquire their distinctive
masculine characters only at a later moult.  Strictly analogous cases occur
at the successive moults of certain male crustaceans.

We have as yet considered the transference of characters, relatively to
their period of development, only in species in a natural state; we will
now turn to domesticated animals, and first touch on monstrosities and
diseases.  The presence of supernumerary digits, and the absence of certain
phalanges, must be determined at an early embryonic period--the tendency to
profuse bleeding is at least congenital, as is probably colour-blindness--
yet these peculiarities, and other similar ones, are often limited in their
transmission to one sex; so that the rule that characters, developed at an
early period, tend to be transmitted to both sexes, here wholly fails.  But
this rule, as before remarked, does not appear to be nearly so general as
the converse one, namely, that characters which appear late in life in one
sex are transmitted exclusively to the same sex.  From the fact of the
above abnormal peculiarities becoming attached to one sex, long before the
sexual functions are active, we may infer that there must be some
difference between the sexes at an extremely early age.  With respect to
sexually-limited diseases, we know too little of the period at which they
originate, to draw any safe conclusion.  Gout, however, seems to fall under
our rule, for it is generally caused by intemperance during manhood, and is
transmitted from the father to his sons in a much more marked manner than
to his daughters.

In the various domestic breeds of sheep, goats, and cattle, the males
differ from their respective females in the shape or development of their
horns, forehead, mane, dewlap, tail, and hump on the shoulders; and these
peculiarities, in accordance with our rule, are not fully developed until a
rather late period of life.  The sexes of dogs do not differ, except that
in certain breeds, especially in the Scotch deer-hound, the male is much
larger and heavier than the female; and, as we shall see in a future
chapter, the male goes on increasing in size to an unusually late period of
life, which, according to rule, will account for his increased size being
transmitted to his male offspring alone.  On the other hand, the tortoise-
shell colour, which is confined to female cats, is quite distinct at birth,
and this case violates the rule.  There is a breed of pigeons in which the
males alone are streaked with black, and the streaks can be detected even
in the nestlings; but they become more conspicuous at each successive
moult, so that this case partly opposes and partly supports the rule.  With
the English Carrier and Pouter pigeons, the full development of the wattle
and the crop occurs rather late in life, and conformably with the rule,
these characters are transmitted in full perfection to the males alone.
The following cases perhaps come within the class previously alluded to, in
which both sexes have varied in the same manner at a rather late period of
life, and have consequently transferred their new characters to both sexes
at a corresponding late period; and if so, these cases are not opposed to
our rule:--there exist sub-breeds of the pigeon, described by Neumeister
(46.  'Das Ganze der Taubenzucht,' 1837, ss. 21, 24.  For the case of the
streaked pigeons, see Dr. Chapuis, 'Le pigeon voyageur Belge,' 1865, p.
87.), in which both sexes change their colour during two or three moults
(as is likewise the case with the Almond Tumbler); nevertheless, these
changes, though occurring rather late in life, are common to both sexes.
One variety of the Canary-bird, namely the London Prize, offers a nearly
analogous case.

With the breeds of the Fowl the inheritance of various characters by one or
both sexes, seems generally determined by the period at which such
characters are developed.  Thus in all the many breeds in which the adult
male differs greatly in colour from the female, as well as from the wild
parent-species, he differs also from the young male, so that the newly-
acquired characters must have appeared at a rather late period of life.  On
the other hand, in most of the breeds in which the two sexes resemble each
other, the young are coloured in nearly the same manner as their parents,
and this renders it probable that their colours first appeared early in
life.  We have instances of this fact in all black and white breeds, in
which the young and old of both sexes are alike; nor can it be maintained
that there is something peculiar in a black or white plumage, which leads
to its transference to both sexes; for the males alone of many natural
species are either black or white, the females being differently coloured.
With the so-called Cuckoo sub-breeds of the fowl, in which the feathers are
transversely pencilled with dark stripes, both sexes and the chickens are
coloured in nearly the same manner.  The laced plumage of the Sebright
bantam is the same in both sexes, and in the young chickens the wing-
feathers are distinctly, though imperfectly laced.  Spangled Hamburgs,
however, offer a partial exception; for the two sexes, though not quite
alike, resemble each other more closely than do the sexes of the aboriginal
parent-species; yet they acquire their characteristic plumage late in life,
for the chickens are distinctly pencilled.  With respect to other
characters besides colour, in the wild-parent species and in most of the
domestic breeds, the males alone possess a well-developed comb; but in the
young of the Spanish fowl it is largely developed at a very early age, and,
in accordance with this early development in the male, it is of unusual
size in the adult female.  In the Game breeds pugnacity is developed at a
wonderfully early age, of which curious proofs could be given; and this
character is transmitted to both sexes, so that the hens, from their
extreme pugnacity, are now generally exhibited in separate pens.  With the
Polish breeds the bony protuberance of the skull which supports the crest
is partially developed even before the chickens are hatched, and the crest
itself soon begins to grow, though at first feebly (47.  For full
particulars and references on all these points respecting the several
breeds of the Fowl, see 'Variation of Animals and Plants under
Domestication,' vol. i. pp. 250, 256.  In regard to the higher animals, the
sexual differences which have arisen under domestication are described in
the same work under the head of each species.); and in this breed the
adults of both sexes are characterised by a great bony protuberance and an
immense crest.

Finally, from what we have now seen of the relation which exists in many
natural species and domesticated races, between the period of the
development of their characters and the manner of their transmission--for
example, the striking fact of the early growth of the horns in the
reindeer, in which both sexes bear horns, in comparison with their much
later growth in the other species in which the male alone bears horns--we
may conclude that one, though not the sole cause of characters being
exclusively inherited by one sex, is their development at a late age.  And
secondly, that one, though apparently a less efficient cause of characters
being inherited by both sexes, is their development at an early age, whilst
the sexes differ but little in constitution.  It appears, however, that
some difference must exist between the sexes even during a very early
embryonic period, for characters developed at this age not rarely become
attached to one sex.

SUMMARY AND CONCLUDING REMARKS.

From the foregoing discussion on the various laws of inheritance, we learn
that the characters of the parents often, or even generally, tend to become
developed in the offspring of the same sex, at the same age, and
periodically at the same season of the year, in which they first appeared
in the parents.  But these rules, owing to unknown causes, are far from
being fixed.  Hence during the modification of a species, the successive
changes may readily be transmitted in different ways; some to one sex, and
some to both; some to the offspring at one age, and some to the offspring
at all ages.  Not only are the laws of inheritance extremely complex, but
so are the causes which induce and govern variability.  The variations thus
induced are preserved and accumulated by sexual selection, which is in
itself an extremely complex affair, depending, as it does, on the ardour in
love, the courage, and the rivalry of the males, as well as on the powers
of perception, the taste, and will of the female.  Sexual selection will
also be largely dominated by natural selection tending towards the general
welfare of the species.  Hence the manner in which the individuals of
either or both sexes have been affected through sexual selection cannot
fail to be complex in the highest degree.

When variations occur late in life in one sex, and are transmitted to the
same sex at the same age, the other sex and the young are left unmodified.
When they occur late in life, but are transmitted to both sexes at the same
age, the young alone are left unmodified.  Variations, however, may occur
at any period of life in one sex or in both, and be transmitted to both
sexes at all ages, and then all the individuals of the species are
similarly modified.  In the following chapters it will be seen that all
these cases frequently occur in nature.

Sexual selection can never act on any animal before the age for
reproduction arrives.  From the great eagerness of the male it has
generally acted on this sex and not on the females.  The males have thus
become provided with weapons for fighting with their rivals, with organs
for discovering and securely holding the female, and for exciting or
charming her.  When the sexes differ in these respects, it is also, as we
have seen, an extremely general law that the adult male differs more or
less from the young male; and we may conclude from this fact that the
successive variations, by which the adult male became modified, did not
generally occur much before the age for reproduction.  Whenever some or
many of the variations occurred early in life, the young males would
partake more or less of the characters of the adult males; and differences
of this kind between the old and young males may be observed in many
species of animals.

It is probable that young male animals have often tended to vary in a
manner which would not only have been of no use to them at an early age,
but would have been actually injurious--as by acquiring bright colours,
which would render them conspicuous to their enemies, or by acquiring
structures, such as great horns, which would expend much vital force in
their development.  Variations of this kind occurring in the young males
would almost certainly be eliminated through natural selection.  With the
adult and experienced males, on the other hand, the advantages derived from
the acquisition of such characters, would more than counterbalance some
exposure to danger, and some loss of vital force.

As variations which give to the male a better chance of conquering other
males, or of finding, securing, or charming the opposite sex, would, if
they happened to arise in the female, be of no service to her, they would
not be preserved in her through sexual selection.  We have also good
evidence with domesticated animals, that variations of all kinds are, if
not carefully selected, soon lost through intercrossing and accidental
deaths.  Consequently in a state of nature, if variations of the above kind
chanced to arise in the female line, and to be transmitted exclusively in
this line, they would be extremely liable to be lost.  If, however, the
females varied and transmitted their newly acquired characters to their
offspring of both sexes, the characters which were advantageous to the
males would be preserved by them through sexual selection, and the two
sexes would in consequence be modified in the same manner, although such
characters were of no use to the females:  but I shall hereafter have to
recur to these more intricate contingencies.  Lastly, the females may
acquire, and apparently have often acquired by transference, characters
from the male sex.

As variations occurring later in life, and transmitted to one sex alone,
have incessantly been taken advantage of and accumulated through sexual
selection in relation to the reproduction of the species; therefore it
appears, at first sight, an unaccountable fact that similar variations have
not frequently been accumulated through natural selection, in relation to
the ordinary habits of life.  If this had occurred, the two sexes would
often have been differently modified, for the sake, for instance, of
capturing prey or of escaping from danger.  Differences of this kind
between the two sexes do occasionally occur, especially in the lower
classes.  But this implies that the two sexes follow different habits in
their struggles for existence, which is a rare circumstance with the higher
animals.  The case, however, is widely different with the reproductive
functions, in which respect the sexes necessarily differ.  For variations
in structure which are related to these functions, have often proved of
value to one sex, and from having arisen at a late period of life, have
been transmitted to one sex alone; and such variations, thus preserved and
transmitted, have given rise to secondary sexual characters.

In the following chapters, I shall treat of the secondary sexual characters
in animals of all classes, and shall endeavour in each case to apply the
principles explained in the present chapter.  The lowest classes will
detain us for a very short time, but the higher animals, especially birds,
must be treated at considerable length.  It should be borne in mind that
for reasons already assigned, I intend to give only a few illustrative
instances of the innumerable structures by the aid of which the male finds
the female, or, when found, holds her.  On the other hand, all structures
and instincts by the aid of which the male conquers other males, and by
which he allures or excites the female, will be fully discussed, as these
are in many ways the most interesting.

SUPPLEMENT ON THE PROPORTIONAL NUMBERS OF THE TWO SEXES IN ANIMALS
BELONGING TO VARIOUS CLASSES.

As no one, as far as I can discover, has paid attention to the relative
numbers of the two sexes throughout the animal kingdom, I will here give
such materials as I have been able to collect, although they are extremely
imperfect.  They consist in only a few instances of actual enumeration, and
the numbers are not very large.  As the proportions are known with
certainty only in mankind, I will first give them as a standard of
comparison.

MAN.

In England during ten years (from 1857 to 1866) the average number of
children born alive yearly was 707,120, in the proportion of 104.5 males to
100 females.  But in 1857 the male births throughout England were as 105.2,
and in 1865 as 104.0 to 100.  Looking to separate districts, in
Buckinghamshire (where about 5000 children are annually born) the MEAN
proportion of male to female births, during the whole period of the above
ten years, was as 102.8 to 100; whilst in N. Wales (where the average
annual births are 12,873) it was as high as 106.2 to 100.  Taking a still
smaller district, viz., Rutlandshire (where the annual births average only
739), in 1864 the male births were as 114.6, and in 1862 as only 97.0 to
100; but even in this small district the average of the 7385 births during
the whole ten years, was as 104.5 to 100:  that is in the same ratio as
throughout England.  (48.  'Twenty-ninth Annual Report of the Registrar-
General for 1866.'  In this report (p. xii.) a special decennial table is
given.)  The proportions are sometimes slightly disturbed by unknown
causes; thus Prof. Faye states "that in some districts of Norway there has
been during a decennial period a steady deficiency of boys, whilst in
others the opposite condition has existed."  In France during forty-four
years the male to the female births have been as 106.2 to 100; but during
this period it has occurred five times in one department, and six times in
another, that the female births have exceeded the males.  In Russia the
average proportion is as high as 108.9, and in Philadelphia in the United
States as 110.5 to 100.  (49.  For Norway and Russia, see abstract of Prof.
Faye's researches, in 'British and Foreign Medico-Chirurg. Review,' April
1867, pp. 343, 345.  For France, the 'Annuaire pour l'An 1867,' p. 213.
For Philadelphia, Dr. Stockton Hough, 'Social Science Assoc.' 1874.  For
the Cape of Good Hope, Quetelet as quoted by Dr. H.H. Zouteveen, in the
Dutch Translation of this work (vol. i. p. 417), where much information is
given on the proportion of the sexes.)  The average for Europe, deduced by
Bickes from about seventy million births, is 106 males to 100 females.  On
the other hand, with white children born at the Cape of Good Hope, the
proportion of males is so low as to fluctuate during successive years
between 90 and 99 males for every 100 females.  It is a singular fact that
with Jews the proportion of male births is decidedly larger than with
Christians:  thus in Prussia the proportion is as 113, in Breslau as 114,
and in Livonia as 120 to 100; the Christian births in these countries being
the same as usual, for instance, in Livonia as 104 to 100.  (50.  In regard
to the Jews, see M. Thury, 'La Loi de Production des Sexes,' 1863, p. 25.)

Prof. Faye remarks that "a still greater preponderance of males would be
met with, if death struck both sexes in equal proportion in the womb and
during birth.  But the fact is, that for every 100 still-born females, we
have in several countries from 134.6 to 144.9 still-born males.  During the
first four or five years of life, also, more male children die than
females, for example in England, during the first year, 126 boys die for
every 100 girls--a proportion which in France is still more unfavourable."
(51.  'British and Foreign Medico-Chirurg. Review,' April 1867, p. 343.
Dr. Stark also remarks ('Tenth Annual Report of Births, Deaths, etc., in
Scotland,' 1867, p. xxviii.) that "These examples may suffice to show that,
at almost every stage of life, the males in Scotland have a greater
liability to death and a higher death-rate than the females.  The fact,
however, of this peculiarity being most strongly developed at that
infantile period of life when the dress, food, and general treatment of
both sexes are alike, seems to prove that the higher male death-rate is an
impressed, natural, and constitutional peculiarity due to sex alone.")  Dr.
Stockton Hough accounts for these facts in part by the more frequent
defective development of males than of females.  We have before seen that
the male sex is more variable in structure than the female; and variations
in important organs would generally be injurious.  But the size of the
body, and especially of the head, being greater in male than female infants
is another cause:  for the males are thus more liable to be injured during
parturition.  Consequently the still-born males are more numerous; and, as
a highly competent judge, Dr. Crichton Browne (52.  'West Riding Lunatic
Asylum Reports,' vol. i. 1871, p. 8.  Sir J. Simpson has proved that the
head of the male infant exceeds that of the female by 3/8ths of an inch in
circumference, and by 1/8th in transverse diameter.  Quetelet has shewn
that woman is born smaller than man; see Dr. Duncan, 'Fecundity, Fertility,
and Sterility,' 1871, p. 382.), believes, male infants often suffer in
health for some years after birth.  Owing to this excess in the death-rate
of male children, both at birth and for some time subsequently, and owing
to the exposure of grown men to various dangers, and to their tendency to
emigrate, the females in all old-settled countries, where statistical
records have been kept, are found to preponderate considerably over the
males.  (53.  With the savage Guaranys of Paraguay, according to the
accurate Azara ('Voyages dans l'Amerique merid.' tom. ii. 1809, pp. 60,
179), the women are to the men in the proportion of 14 to 13.)

It seems at first sight a mysterious fact that in different nations, under
different conditions and climates, in Naples, Prussia, Westphalia, Holland,
France, England and the United States, the excess of male over female
births is less when they are illegitimate than when legitimate.  (54.
Babbage, 'Edinburgh Journal of Science,' 1829, vol. i. p. 88; also p. 90,
on still-born children.  On illegitimate children in England, see 'Report
of Registrar-General for 1866,' p. xv.)  This has been explained by
different writers in many different ways, as from the mothers being
generally young, from the large proportion of first pregnancies, etc.  But
we have seen that male infants, from the large size of their heads, suffer
more than female infants during parturition; and as the mothers of
illegitimate children must be more liable than other women to undergo bad
labours, from various causes, such as attempts at concealment by tight
lacing, hard work, distress of mind, etc., their male infants would
proportionably suffer.  And this probably is the most efficient of all the
causes of the proportion of males to females born alive being less amongst
illegitimate children than amongst the legitimate.  With most animals the
greater size of the adult male than of the female, is due to the stronger
males having conquered the weaker in their struggles for the possession of
the females, and no doubt it is owing to this fact that the two sexes of at
least some animals differ in size at birth.  Thus we have the curious fact
that we may attribute the more frequent deaths of male than female infants,
especially amongst the illegitimate, at least in part to sexual selection.

It has often been supposed that the relative age of the two parents
determine the sex of the offspring; and Prof. Leuckart (55.  Leuckart, in
Wagner 'Handwoerterbuch der Phys.' B. iv. 1853, s. 774.) has advanced what
he considers sufficient evidence, with respect to man and certain
domesticated animals, that this is one important though not the sole factor
in the result.  So again the period of impregnation relatively to the state
of the female has been thought by some to be the efficient cause; but
recent observations discountenance this belief.  According to Dr. Stockton
Hough (56.  'Social Science Association of Philadelphia,' 1874.), the
season of the year, the poverty or wealth of the parents, residence in the
country or in cities, the crossing of foreign immigrants, etc., all
influence the proportion of the sexes.  With mankind, polygamy has also
been supposed to lead to the birth of a greater proportion of female
infants; but Dr. J. Campbell (57.  'Anthropological Review,' April 1870, p.
cviii.) carefully attended to this subject in the harems of Siam, and
concludes that the proportion of male to female births is the same as from
monogamous unions.  Hardly any animal has been rendered so highly
polygamous as the English race-horse, and we shall immediately see that his
male and female offspring are almost exactly equal in number.  I will now
give the facts which I have collected with respect to the proportional
numbers of the sexes of various animals; and will then briefly discuss how
far selection has come into play in determining the result.

HORSES.

Mr. Tegetmeier has been so kind as to tabulate for me from the 'Racing
Calendar' the births of race-horses during a period of twenty-one years,
viz., from 1846 to 1867; 1849 being omitted, as no returns were that year
published.  The total births were 25,560 (58.  During eleven years a record
was kept of the number of mares which proved barren or prematurely slipped
their foals; and it deserves notice, as shewing how infertile these highly-
nurtured and rather closely-interbred animals have become, that not far
from one-third of the mares failed to produce living foals.  Thus during
1866, 809 male colts and 816 female colts were born, and 743 mares failed
to produce offspring.  During 1867, 836 males and 902 females were born,
and 794 mares failed.), consisting of 12,763 males and 12,797 females, or
in the proportion of 99.7 males to 100 females.  As these numbers are
tolerably large, and as they are drawn from all parts of England, during
several years, we may with much confidence conclude that with the domestic
horse, or at least with the race-horse, the two sexes are produced in
almost equal numbers.  The fluctuations in the proportions during
successive years are closely like those which occur with mankind, when a
small and thinly-populated area is considered; thus in 1856 the male horses
were as 107.1, and in 1867 as only 92.6 to 100 females.  In the tabulated
returns the proportions vary in cycles, for the males exceeded the females
during six successive years; and the females exceeded the males during two
periods each of four years; this, however, may be accidental; at least I
can detect nothing of the kind with man in the decennial table in the
Registrar's Report for 1866.

DOGS.

During a period of twelve years, from 1857 to 1868, the births of a large
number of greyhounds, throughout England, were sent to the 'Field'
newspaper; and I am again indebted to Mr. Tegetmeier for carefully
tabulating the results.  The recorded births were 6878, consisting of 3605
males and 3273 females, that is, in the proportion of 110.1 males to 100
females.  The greatest fluctuations occurred in 1864, when the proportion
was as 95.3 males, and in 1867, as 116.3 males to 100 females.  The above
average proportion of 110.1 to 100 is probably nearly correct in the case
of the greyhound, but whether it would hold with other domesticated breeds
is in some degree doubtful.  Mr. Cupples has enquired from several great
breeders of dogs, and finds that all without exception believe that females
are produced in excess; but he suggests that this belief may have arisen
from females being less valued, and from the consequent disappointment
producing a stronger impression on the mind.

SHEEP.

The sexes of sheep are not ascertained by agriculturists until several
months after birth, at the period when the males are castrated; so that the
following returns do not give the proportions at birth.  Moreover, I find
that several great breeders in Scotland, who annually raise some thousand
sheep, are firmly convinced that a larger proportion of males than of
females die during the first year or two.  Therefore the proportion of
males would be somewhat larger at birth than at the age of castration.
This is a remarkable coincidence with what, as we have seen, occurs with
mankind, and both cases probably depend on the same cause.  I have received
returns from four gentlemen in England who have bred Lowland sheep, chiefly
Leicesters, during the last ten to sixteen years; they amount altogether to
8965 births, consisting of 4407 males and 4558 females; that is in the
proportion of 96.7 males to 100 females.  With respect to Cheviot and
black-faced sheep bred in Scotland, I have received returns from six
breeders, two of them on a large scale, chiefly for the years 1867-1869,
but some of the returns extend back to 1862.  The total number recorded
amounts to 50,685, consisting of 25,071 males and 25,614 females or in the
proportion of 97.9 males to 100 females.  If we take the English and Scotch
returns together, the total number amounts to 59,650, consisting of 29,478
males and 30,172 females, or as 97.7 to 100.  So that with sheep at the age
of castration the females are certainly in excess of the males, but
probably this would not hold good at birth.  (59.  I am much indebted to
Mr. Cupples for having procured for me the above returns from Scotland, as
well as some of the following returns on cattle.  Mr. R. Elliot, of
Laighwood, first called my attention to the premature deaths of the males,
--a statement subsequently confirmed by Mr. Aitchison and others.  To this
latter gentleman, and to Mr. Payan, I owe my thanks for large returns as to
sheep.)

Of CATTLE I have received returns from nine gentlemen of 982 births, too
few to be trusted; these consisted of 477 bull-calves and 505 cow-calves;
i.e., in the proportion of 94.4 males to 100 females.  The Rev. W.D. Fox
informs me that in 1867 out of 34 calves born on a farm in Derbyshire only
one was a bull.  Mr. Harrison Weir has enquired from several breeders of
PIGS, and most of them estimate the male to the female births as about 7 to
6.  This same gentleman has bred RABBITS for many years, and has noticed
that a far greater number of bucks are produced than does.  But estimations
are of little value.

Of mammalia in a state of nature I have been able to learn very little.  In
regard to the common rat, I have received conflicting statements.  Mr. R.
Elliot, of Laighwood, informs me that a rat-catcher assured him that he had
always found the males in great excess, even with the young in the nest.
In consequence of this, Mr. Elliot himself subsequently examined some
hundred old ones, and found the statement true.  Mr. F. Buckland has bred a
large number of white rats, and he also believes that the males greatly
exceed the females.  In regard to Moles, it is said that "the males are
much more numerous than the females" (60.  Bell, 'History of British
Quadrupeds,' p. 100.):  and as the catching of these animals is a special
occupation, the statement may perhaps be trusted.  Sir A. Smith, in
describing an antelope of S. Africa (61.  'Illustrations of the Zoology of
S. Africa,' 1849, pl. 29.) (Kobus ellipsiprymnus), remarks, that in the
herds of this and other species, the males are few in number compared with
the females:  the natives believe that they are born in this proportion;
others believe that the younger males are expelled from the herds, and Sir
A. Smith says, that though he has himself never seen herds consisting of
young males alone, others affirm that this does occur.  It appears probable
that the young when expelled from the herd, would often fall a prey to the
many beasts of prey of the country.

BIRDS.

With respect to the FOWL, I have received only one account, namely, that
out of 1001 chickens of a highly-bred stock of Cochins, reared during eight
years by Mr. Stretch, 487 proved males and 514 females; i.e., as 94.7 to
100.  In regard to domestic pigeons there is good evidence either that the
males are produced in excess, or that they live longer; for these birds
invariably pair, and single males, as Mr. Tegetmeier informs me, can always
be purchased cheaper than females.  Usually the two birds reared from the
two eggs laid in the same nest are a male and a female; but Mr. Harrison
Weir, who has been so large a breeder, says that he has often bred two
cocks from the same nest, and seldom two hens; moreover, the hen is
generally the weaker of the two, and more liable to perish.

With respect to birds in a state of nature, Mr. Gould and others (62.
Brehm ('Thierleben,' B. iv. s. 990) comes to the same conclusion.) are
convinced that the males are generally the more numerous; and as the young
males of many species resemble the females, the latter would naturally
appear to be the more numerous.  Large numbers of pheasants are reared by
Mr. Baker of Leadenhall from eggs laid by wild birds, and he informs Mr.
Jenner Weir that four or five males to one female are generally produced.
An experienced observer remarks (63.  On the authority of L. Lloyd, 'Game
Birds of Sweden,' 1867, pp. 12, 132.), that in Scandinavia the broods of
the capercailzie and black-cock contain more males than females; and that
with the Dal-ripa (a kind of ptarmigan) more males than females attend the
leks or places of courtship; but this latter circumstance is accounted for
by some observers by a greater number of hen birds being killed by vermin.
From various facts given by White of Selborne (64.  'Nat. Hist. of
Selborne,' letter xxix. edit. of 1825, vol. i. p. 139.), it seems clear
that the males of the partridge must be in considerable excess in the south
of England; and I have been assured that this is the case in Scotland.  Mr.
Weir on enquiring from the dealers, who receive at certain seasons large
numbers of ruffs (Machetes pugnax), was told that the males are much the
more numerous.  This same naturalist has also enquired for me from the
birdcatchers, who annually catch an astonishing number of various small
species alive for the London market, and he was unhesitatingly answered by
an old and trustworthy man, that with the chaffinch the males are in large
excess:  he thought as high as 2 males to 1 female, or at least as high as
5 to 3.  (65.  Mr. Jenner Weir received similar information, on making
enquiries during the following year.  To shew the number of living
chaffinches caught, I may mention that in 1869 there was a match between
two experts, and one man caught in a day 62, and another 40, male
chaffinches.  The greatest number ever caught by one man in a single day
was 70.)  The males of the blackbird, he likewise maintained, were by far
the more numerous, whether caught by traps or by netting at night.  These
statements may apparently be trusted, because this same man said that the
sexes are about equal with the lark, the twite (Linaria montana), and
goldfinch.  On the other hand, he is certain that with the common linnet,
the females preponderate greatly, but unequally during different years;
during some years he has found the females to the males as four to one.  It
should, however, be borne in mind, that the chief season for catching birds
does not begin till September, so that with some species partial migrations
may have begun, and the flocks at this period often consist of hens alone.
Mr. Salvin paid particular attention to the sexes of the humming-birds in
Central America, and is convinced that with most of the species the males
are in excess; thus one year he procured 204 specimens belonging to ten
species, and these consisted of 166 males and of only 38 females.  With two
other species the females were in excess:  but the proportions apparently
vary either during different seasons or in different localities; for on one
occasion the males of Campylopterus hemileucurus were to the females as 5
to 2, and on another occasion (66.  'Ibis,' vol. ii. p. 260, as quoted in
Gould's 'Trochilidae,' 1861, p. 52.  For the foregoing proportions, I am
indebted to Mr. Salvin for a table of his results.) in exactly the reversed
ratio.  As bearing on this latter point, I may add, that Mr. Powys found in
Corfu and Epirus the sexes of the chaffinch keeping apart, and "the females
by far the most numerous"; whilst in Palestine Mr. Tristram found "the male
flocks appearing greatly to exceed the female in number."  (67.  'Ibis,'
1860, p. 137; and 1867, p. 369.)  So again with the Quiscalus major, Mr. G.
Taylor says, that in Florida there were "very few females in proportion to
the males," (68.  'Ibis,' 1862, p. 187.) whilst in Honduras the proportion
was the other way, the species there having the character of a polygamist.

FISH.

With fish the proportional numbers of the sexes can be ascertained only by
catching them in the adult or nearly adult state; and there are many
difficulties in arriving at any just conclusion.  (69.  Leuckart quotes
Bloch (Wagner, 'Handwoerterbuch der Phys.' B. iv. 1853, s. 775), that with
fish there are twice as many males as females.)  Infertile females might
readily be mistaken for males, as Dr. Gunther has remarked to me in regard
to trout.  With some species the males are believed to die soon after
fertilising the ova.  With many species the males are of much smaller size
than the females, so that a large number of males would escape from the
same net by which the females were caught.  M. Carbonnier (70.  Quoted in
the 'Farmer,' March 18, 1869, p. 369.), who has especially attended to the
natural history of the pike (Esox lucius), states that many males, owing to
their small size, are devoured by the larger females; and he believes that
the males of almost all fish are exposed from this same cause to greater
danger than the females.  Nevertheless, in the few cases in which the
proportional numbers have been actually observed, the males appear to be
largely in excess.  Thus Mr. R. Buist, the superintendent of the
Stormontfield experiments, says that in 1865, out of 70 salmon first landed
for the purpose of obtaining the ova, upwards of 60 were males.  In 1867 he
again "calls attention to the vast disproportion of the males to the
females.  We had at the outset at least ten males to one female."
Afterwards females sufficient for obtaining ova were procured.  He adds,
"from the great proportion of the males, they are constantly fighting and
tearing each other on the spawning-beds."  (71.  'The Stormontfield
Piscicultural Experiments,' 1866, p. 23.  The 'Field' newspaper, June 29,
1867.)  This disproportion, no doubt, can be accounted for in part, but
whether wholly is doubtful, by the males ascending the rivers before the
females.  Mr. F. Buckland remarks in regard to trout, that "it is a curious
fact that the males preponderate very largely in number over the females.
It INVARIABLY happens that when the first rush of fish is made to the net,
there will be at least seven or eight males to one female found captive.  I
cannot quite account for this; either the males are more numerous than the
females, or the latter seek safety by concealment rather than flight."  He
then adds, that by carefully searching the banks sufficient females for
obtaining ova can be found.  (72.  'Land and Water,' 1868, p. 41.)  Mr. H.
Lee informs me that out of 212 trout, taken for this purpose in Lord
Portsmouth's park, 150 were males and 62 females.

The males of the Cyprinidae likewise seem to be in excess; but several
members of this Family, viz., the carp, tench, bream and minnow, appear
regularly to follow the practice, rare in the animal kingdom, of polyandry;
for the female whilst spawning is always attended by two males, one on each
side, and in the case of the bream by three or four males.  This fact is so
well known, that it is always recommended to stock a pond with two male
tenches to one female, or at least with three males to two females.  With
the minnow, an excellent observer states, that on the spawning-beds the
males are ten times as numerous as the females; when a female comes amongst
the males, "she is immediately pressed closely by a male on each side; and
when they have been in that situation for a time, are superseded by other
two males."  (73.  Yarrell, 'Hist. British Fishes,' vol. i. 1826, p. 307;
on the Cyprinus carpio, p. 331; on the Tinca vulgaris, p. 331; on the
Abramis brama, p. 336.  See, for the minnow (Leuciscus phoxinus), 'Loudon's
Magazine of Natural History,' vol. v. 1832, p. 682.)

INSECTS.

In this great Class, the Lepidoptera almost alone afford means for judging
of the proportional numbers of the sexes; for they have been collected with
special care by many good observers, and have been largely bred from the
egg or caterpillar state.  I had hoped that some breeders of silk-moths
might have kept an exact record, but after writing to France and Italy, and
consulting various treatises, I cannot find that this has ever been done.
The general opinion appears to be that the sexes are nearly equal, but in
Italy, as I hear from Professor Canestrini, many breeders are convinced
that the females are produced in excess.  This same naturalist, however,
informs me, that in the two yearly broods of the Ailanthus silk-moth
(Bombyx cynthia), the males greatly preponderate in the first, whilst in
the second the two sexes are nearly equal, or the females rather in excess.

In regard to Butterflies in a state of nature, several observers have been
much struck by the apparently enormous preponderance of the males.  (74.
Leuckart quotes Meinecke (Wagner, 'Handwoerterbuch der Phys.' B. iv. 1853,
s. 775) that the males of Butterflies are three or four times as numerous
as the females.)  Thus Mr. Bates (75.  'The Naturalist on the Amazons,'
vol. ii. 1863, pp. 228, 347.), in speaking of several species, about a
hundred in number, which inhabit the upper Amazons, says that the males are
much more numerous than the females, even in the proportion of a hundred to
one.  In North America, Edwards, who had great experience, estimates in the
genus Papilio the males to the females as four to one; and Mr. Walsh, who
informed me of this statement, says that with P. turnus this is certainly
the case.  In South Africa, Mr. R. Trimen found the males in excess in 19
species (76.  Four of these cases are given by Mr. Trimen in his
'Rhopalocera Africae Australis.'); and in one of these, which swarms in
open places, he estimated the number of males as fifty to one female.  With
another species, in which the males are numerous in certain localities, he
collected only five females during seven years.  In the island of Bourbon,
M. Maillard states that the males of one species of Papilio are twenty
times as numerous as the females.  (77.  Quoted by Trimen, 'Transactions of
the Ent. Society,' vol. v. part iv. 1866, p. 330.)  Mr. Trimen informs me
that as far as he has himself seen, or heard from others, it is rare for
the females of any butterfly to exceed the males in number; but three South
African species perhaps offer an exception.  Mr. Wallace (78.
'Transactions, Linnean Society,' vol. xxv. p. 37.) states that the females
of Ornithoptera croesus, in the Malay archipelago, are more common and more
easily caught than the males; but this is a rare butterfly.  I may here
add, that in Hyperythra, a genus of moths, Guenee says, that from four to
five females are sent in collections from India for one male.

When this subject of the proportional numbers of the sexes of insects was
brought before the Entomological Society (79.  'Proceedings, Entomological
Society,' Feb. 17, 1868.), it was generally admitted that the males of most
Lepidoptera, in the adult or imago state, are caught in greater numbers
than the females:  but this fact was attributed by various observers to the
more retiring habits of the females, and to the males emerging earlier from
the cocoon.  This latter circumstance is well known to occur with most
Lepidoptera, as well as with other insects.  So that, as M. Personnat
remarks, the males of the domesticated Bombyx Yamamai, are useless at the
beginning of the season, and the females at the end, from the want of
mates.  (80.  Quoted by Dr. Wallace in 'Proceedings, Entomological
Society,' 3rd series, vol. v. 1867, p. 487.)  I cannot, however, persuade
myself that these causes suffice to explain the great excess of males, in
the above cases of certain butterflies which are extremely common in their
native countries.  Mr. Stainton, who has paid very close attention during
many years to the smaller moths, informs me that when he collected them in
the imago state, he thought that the males were ten times as numerous as
the females, but that since he has reared them on a large scale from the
caterpillar state, he is convinced that the females are the more numerous.
Several entomologists concur in this view.  Mr. Doubleday, however, and
some others, take an opposite view, and are convinced that they have reared
from the eggs and caterpillars a larger proportion of males than of
females.

Besides the more active habits of the males, their earlier emergence from
the cocoon, and in some cases their frequenting more open stations, other
causes may be assigned for an apparent or real difference in the
proportional numbers of the sexes of Lepidoptera, when captured in the
imago state, and when reared from the egg or caterpillar state.  I hear
from Professor Canestrini, that it is believed by many breeders in Italy,
that the female caterpillar of the silk-moth suffers more from the recent
disease than the male; and Dr. Staudinger informs me that in rearing
Lepidoptera more females die in the cocoon than males.  With many species
the female caterpillar is larger than the male, and a collector would
naturally choose the finest specimens, and thus unintentionally collect a
larger number of females.  Three collectors have told me that this was
their practice; but Dr. Wallace is sure that most collectors take all the
specimens which they can find of the rarer kinds, which alone are worth the
trouble of rearing.  Birds when surrounded by caterpillars would probably
devour the largest; and Professor Canestrini informs me that in Italy some
breeders believe, though on insufficient evidence, that in the first broods
of the Ailanthus silk-moth, the wasps destroy a larger number of the female
than of the male caterpillars.  Dr. Wallace further remarks that female
caterpillars, from being larger than the males, require more time for their
development, and consume more food and moisture:  and thus they would be
exposed during a longer time to danger from ichneumons, birds, etc., and in
times of scarcity would perish in greater numbers.  Hence it appears quite
possible that in a state of nature, fewer female Lepidoptera may reach
maturity than males; and for our special object we are concerned with their
relative numbers at maturity, when the sexes are ready to propagate their
kind.

The manner in which the males of certain moths congregate in extraordinary
numbers round a single female, apparently indicates a great excess of
males, though this fact may perhaps be accounted for by the earlier
emergence of the males from their cocoons.  Mr. Stainton informs me that
from twelve to twenty males, may often be seen congregated round a female
Elachista rufocinerea.  It is well known that if a virgin Lasiocampa
quercus or Saturnia carpini be exposed in a cage, vast numbers of males
collect round her, and if confined in a room will even come down the
chimney to her.  Mr. Doubleday believes that he has seen from fifty to a
hundred males of both these species attracted in the course of a single day
by a female in confinement.  In the Isle of Wight Mr. Trimen exposed a box
in which a female of the Lasiocampa had been confined on the previous day,
and five males soon endeavoured to gain admittance.  In Australia, Mr.
Verreaux, having placed the female of a small Bombyx in a box in his
pocket, was followed by a crowd of males, so that about 200 entered the
house with him.  (81.  Blanchard, 'Metamorphoses, Moeurs des Insectes,'
1868, pp. 225-226.)

Mr. Doubleday has called my attention to M. Staudinger's (82.
'Lepidopteren-Doubletten Liste,' Berlin, No. x. 1866.) list of Lepidoptera,
which gives the prices of the males and females of 300 species or well-
marked varieties of butterflies (Rhopalocera).  The prices for both sexes
of the very common species are of course the same; but in 114 of the rarer
species they differ; the males being in all cases, excepting one, the
cheaper.  On an average of the prices of the 113 species, the price of the
male to that of the female is as 100 to 149; and this apparently indicates
that inversely the males exceed the females in the same proportion.  About
2000 species or varieties of moths (Heterocera) are catalogued, those with
wingless females being here excluded on account of the difference in habits
between the two sexes:  of these 2000 species, 141 differ in price
according to sex, the males of 130 being cheaper, and those of only 11
being dearer than the females.  The average price of the males of the 130
species, to that of the females, is as 100 to 143.  With respect to the
butterflies in this priced list, Mr. Doubleday thinks (and no man in
England has had more experience), that there is nothing in the habits of
the species which can account for the difference in the prices of the two
sexes, and that it can be accounted for only by an excess in the number of
the males.  But I am bound to add that Dr. Staudinger informs me, that he
is himself of a different opinion.  He thinks that the less active habits
of the females and the earlier emergence of the males will account for his
collectors securing a larger number of males than of females, and
consequently for the lower prices of the former.  With respect to specimens
reared from the caterpillar-state, Dr. Staudinger believes, as previously
stated, that a greater number of females than of males die whilst confined
to the cocoons.  He adds that with certain species one sex seems to
preponderate over the other during certain years.

Of direct observations on the sexes of Lepidoptera, reared either from eggs
or caterpillars, I have received only the few following cases:  (See
following table.)

So that in these eight lots of cocoons and eggs, males were produced in
excess.  Taken together the proportion of males is as 122.7 to 100 females.
But the numbers are hardly large enough to be trustworthy.

On the whole, from these various sources of evidence, all pointing in the
same direction, I infer that with most species of Lepidoptera, the mature
males generally exceed the females in number, whatever the proportions may
be at their first emergence from the egg.

                                                    Males   Females
  The Rev. J. Hellins* of Exeter reared, during
    1868, imagos of 73 species, which
    consisted of                                     153       137

  Mr. Albert Jones of Eltham reared, during
    1868, imagos of 9 species, which
    consisted of                                     159       126

  During 1869 he reared imagos from 4 species
    consisting of                                    114       112

  Mr. Buckler of Emsworth, Hants, during 1869,
    reared imagos from 74 species,
    consisting of                                    180       169

  Dr. Wallace of Colchester reared from one
    brood of Bombyx cynthia                           52        48

  Dr. Wallace raised, from cocoons of Bombyx
    Pernyi sent from China, during 1869              224       123

  Dr. Wallace raised, during 1868 and 1869, from
    two lots of cocoons of Bombyx yamamai             52        46

                                           Total     934       761

(*83.  This naturalist has been so kind as to send me some results from
former years, in which the females seemed to preponderate; but so many of
the figures were estimates, that I found it impossible to tabulate them.)

With reference to the other Orders of insects, I have been able to collect
very little reliable information.  With the stag-beetle (Lucanus cervus)
"the males appear to be much more numerous than the females"; but when, as
Cornelius remarked during 1867, an unusual number of these beetles appeared
in one part of Germany, the females appeared to exceed the males as six to
one.  With one of the Elateridae, the males are said to be much more
numerous than the females, and "two or three are often found united with
one female (84.  Gunther's 'Record of Zoological Literature,' 1867, p. 260.
On the excess of female Lucanus, ibid, p. 250.  On the males of Lucanus in
England, Westwood,' 'Modern Classification of Insects,' vol. i. p. 187.  On
the Siagonium, ibid. p. 172.); so that here polyandry seems to prevail."
With Siagonium (Staphylinidae), in which the males are furnished with
horns, "the females are far more numerous than the opposite sex."  Mr.
Janson stated at the Entomological Society that the females of the bark
feeding Tomicus villosus are so common as to be a plague, whilst the males
are so rare as to be hardly known.

It is hardly worth while saying anything about the proportion of the sexes
in certain species and even groups of insects, for the males are unknown or
very rare, and the females are parthenogenetic, that is, fertile without
sexual union; examples of this are afforded by several of the Cynipidae.
(85.  Walsh in 'The American Entomologist,' vol. i. 1869, p. 103.  F.
Smith, 'Record of Zoological Lit.' 1867, p. 328.)  In all the gall-making
Cynipidae known to Mr. Walsh, the females are four or five times as
numerous as the males; and so it is, as he informs me, with the gall-making
Cecidomyiidae (Diptera).  With some common species of Saw-flies
(Tenthredinae) Mr. F. Smith has reared hundreds of specimens from larvae of
all sizes, but has never reared a single male; on the other hand, Curtis
says (86.  'Farm Insects,' pp. 45-46.), that with certain species
(Athalia), bred by him, the males were to the females as six to one; whilst
exactly the reverse occurred with the mature insects of the same species
caught in the fields.  In the family of bees, Hermann Mueller (87.
'Anwendung der Darwin'schen Lehre,' Verh. d. n. Jahrg., xxiv.), collected a
large number of specimens of many species, and reared others from the
cocoons, and counted the sexes.  He found that the males of some species
greatly exceeded the females in number; in others the reverse occurred; and
in others the two sexes were nearly equal.  But as in most cases the males
emerge from the cocoons before the females, they are at the commencement of
the breeding-season practically in excess.  Mueller also observed that the
relative number of the two sexes in some species differed much in different
localities.  But as H. Mueller has himself remarked to me, these remarks
must be received with some caution, as one sex might more easily escape
observation than the other.  Thus his brother Fritz Mueller has noticed in
Brazil that the two sexes of the same species of bee sometimes frequent
different kinds of flowers.  With respect to the Orthoptera, I know hardly
anything about the relative number of the sexes:  Korte (88.  'Die Strich,
Zug oder Wanderheuschrecke,' 1828, p. 20.), however, says that out of 500
locusts which he examined, the males were to the females as five to six.
With the Neuroptera, Mr. Walsh states that in many, but by no means in all
the species of the Odonatous group, there is a great overplus of males:  in
the genus Hetaerina, also, the males are generally at least four times as
numerous as the females.  In certain species in the genus Gomphus the males
are equally in excess, whilst in two other species, the females are twice
or thrice as numerous as the males.  In some European species of Psocus
thousands of females may be collected without a single male, whilst with
other species of the same genus both sexes are common.  (89.  'Observations
on N. American Neuroptera,' by H. Hagen and B.D. Walsh, 'Proceedings, Ent.
Soc. Philadelphia,' Oct. 1863, pp. 168, 223, 239.)  In England, Mr.
MacLachlan has captured hundreds of the female Apatania muliebris, but has
never seen the male; and of Boreus hyemalis only four or five males have
been seen here.  (90.  'Proceedings, Ent. Soc. London,' Feb. 17, 1868.)
With most of these species (excepting the Tenthredinae) there is at present
no evidence that the females are subject to parthenogenesis; and thus we
see how ignorant we are of the causes of the apparent discrepancy in the
proportion of the two sexes.

In the other classes of the Articulata I have been able to collect still
less information.  With spiders, Mr. Blackwall, who has carefully attended
to this class during many years, writes to me that the males from their
more erratic habits are more commonly seen, and therefore appear more
numerous.  This is actually the case with a few species; but he mentions
several species in six genera, in which the females appear to be much more
numerous than the males.  (91.  Another great authority with respect to
this class, Prof. Thorell of Upsala ('On European Spiders,' 1869-70, part
i. p. 205), speaks as if female spiders were generally commoner than the
males.)  The small size of the males in comparison with the females (a
peculiarity which is sometimes carried to an extreme degree), and their
widely different appearance, may account in some instances for their rarity
in collections.  (92.  See, on this subject, Mr. O.P. Cambridge, as quoted
in 'Quarterly Journal of Science,' 1868, page 429.)

Some of the lower Crustaceans are able to propagate their kind sexually,
and this will account for the extreme rarity of the males; thus von Siebold
(93.  'Beitraege zur Parthenogenesis,' p. 174.) carefully examined no less
than 13,000 specimens of Apus from twenty-one localities, and amongst these
he found only 319 males.  With some other forms (as Tanais and Cypris), as
Fritz Mueller informs me, there is reason to believe that the males are much
shorter-lived than the females; and this would explain their scarcity,
supposing the two sexes to be at first equal in number.  On the other hand,
Mueller has invariably taken far more males than females of the Diastylidae
and of Cypridina on the shores of Brazil:  thus with a species in the
latter genus, 63 specimens caught the same day included 57 males; but he
suggests that this preponderance may be due to some unknown difference in
the habits of the two sexes.  With one of the higher Brazilian crabs,
namely a Gelasimus, Fritz Mueller found the males to be more numerous than
the females.  According to the large experience of Mr. C. Spence Bate, the
reverse seems to be the case with six common British crabs, the names of
which he has given me.

THE PROPORTION OF THE SEXES IN RELATION TO NATURAL SELECTION.

There is reason to suspect that in some cases man has by selection
indirectly influenced his own sex-producing powers.  Certain women tend to
produce during their whole lives more children of one sex than of the
other:  and the same holds good of many animals, for instance, cows and
horses; thus Mr. Wright of Yeldersley House informs me that one of his Arab
mares, though put seven times to different horses, produced seven fillies.
Though I have very little evidence on this head, analogy would lead to the
belief, that the tendency to produce either sex would be inherited like
almost every other peculiarity, for instance, that of producing twins; and
concerning the above tendency a good authority, Mr. J. Downing, has
communicated to me facts which seem to prove that this does occur in
certain families of short-horn cattle.  Col. Marshall (94.  'The Todas,'
1873, pp. 100, 111, 194, 196.) has recently found on careful examination
that the Todas, a hill-tribe of India, consist of 112 males and 84 females
of all ages--that is in a ratio of 133.3 males to 100 females.  The Todas,
who are polyandrous in their marriages, during former times invariably
practised female infanticide; but this practice has now been discontinued
for a considerable period.  Of the children born within late years, the
males are more numerous than the females, in the proportion of 124 to 100.
Colonel Marshall accounts for this fact in the following ingenious manner.
"Let us for the purpose of illustration take three families as representing
an average of the entire tribe; say that one mother gives birth to six
daughters and no sons; a second mother has six sons only, whilst the third
mother has three sons and three daughters.  The first mother, following the
tribal custom, destroys four daughters and preserves two.  The second
retains her six sons.  The third kills two daughters and keeps one, as also
her three sons.  We have then from the three families, nine sons and three
daughters, with which to continue the breed.  But whilst the males belong
to families in which the tendency to produce sons is great, the females are
of those of a converse inclination.  Thus the bias strengthens with each
generation, until, as we find, families grow to have habitually more sons
than daughters."

That this result would follow from the above form of infanticide seems
almost certain; that is if we assume that a sex-producing tendency is
inherited.  But as the above numbers are so extremely scanty, I have
searched for additional evidence, but cannot decide whether what I have
found is trustworthy; nevertheless the facts are, perhaps, worth giving.
The Maories of New Zealand have long practised infanticide; and Mr. Fenton
(95.  'Aboriginal Inhabitants of New Zealand:  Government Report,' 1859, p.
36.) states that he "has met with instances of women who have destroyed
four, six, and even seven children, mostly females.  However, the universal
testimony of those best qualified to judge, is conclusive that this custom
has for many years been almost extinct.  Probably the year 1835 may be
named as the period of its ceasing to exist."  Now amongst the New
Zealanders, as with the Todas, male births are considerably in excess.  Mr.
Fenton remarks (p. 30), "One fact is certain, although the exact period of
the commencement of this singular condition of the disproportion of the
sexes cannot be demonstratively fixed, it is quite clear that this course
of decrease was in full operation during the years 1830 to 1844, when the
non-adult population of 1844 was being produced, and has continued with
great energy up to the present time."  The following statements are taken
from Mr. Fenton (p. 26), but as the numbers are not large, and as the
census was not accurate, uniform results cannot be expected.  It should be
borne in mind in this and the following cases, that the normal state of
every population is an excess of women, at least in all civilised
countries, chiefly owing to the greater mortality of the male sex during
youth, and partly to accidents of all kinds later in life.  In 1858, the
native population of New Zealand was estimated as consisting of 31,667
males and 24,303 females of all ages, that is in the ratio of 130.3 males
to 100 females.  But during this same year, and in certain limited
districts, the numbers were ascertained with much care, and the males of
all ages were here 753 and the females 616; that is in the ratio of 122.2
males to 100 females.  It is more important for us that during this same
year of 1858, the NON-ADULT males within the same district were found to be
178, and the NON-ADULT females 142, that is in the ratio of 125.3 to 100.
It may be added that in 1844, at which period female infanticide had only
lately ceased, the NON-ADULT males in one district were 281, and the NON-
ADULT females only 194, that is in the ratio of 144.8 males to 100 females.

In the Sandwich Islands, the males exceed the females in number.
Infanticide was formerly practised there to a frightful extent, but was by
no means confined to female infants, as is shewn by Mr. Ellis (96.
'Narrative of a Tour through Hawaii,' 1826, p. 298.), and as I have been
informed by Bishop Staley and the Rev. Mr. Coan.  Nevertheless, another
apparently trustworthy writer, Mr. Jarves (97.  'History of the Sandwich
Islands,' 1843, p. 93.), whose observations apply to the whole archipelago,
remarks:--"Numbers of women are to be found, who confess to the murder of
from three to six or eight children," and he adds, "females from being
considered less useful than males were more often destroyed."  From what is
known to occur in other parts of the world, this statement is probable; but
must be received with much caution.  The practice of infanticide ceased
about the year 1819, when idolatry was abolished and missionaries settled
in the Islands.  A careful census in 1839 of the adult and taxable men and
women in the island of Kauai and in one district of Oahu (Jarves, p. 404),
gives 4723 males and 3776 females; that is in the ratio of 125.08 to 100.
At the same time the number of males under fourteen years in Kauai and
under eighteen in Oahu was 1797, and of females of the same ages 1429; and
here we have the ratio of 125.75 males to 100 females.

In a census of all the islands in 1850 (98.  This is given in the Rev. H.T.
Cheever's 'Life in the Sandwich Islands,' 1851, p. 277.), the males of all
ages amount to 36,272, and the females to 33,128, or as 109.49 to 100.  The
males under seventeen years amounted to 10,773, and the females under the
same age to 9593, or as 112.3 to 100.  From the census of 1872, the
proportion of males of all ages (including half-castes) to females, is as
125.36 to 100.  It must be borne in mind that all these returns for the
Sandwich Islands give the proportion of living males to living females, and
not of the births; and judging from all civilised countries the proportion
of males would have been considerably higher if the numbers had referred to
births.  (99.  Dr. Coulter, in describing ('Journal R. Geograph. Soc.' vol.
v. 1835, p. 67) the state of California about the year 1830, says that the
natives, reclaimed by the Spanish missionaries, have nearly all perished,
or are perishing, although well treated, not driven from their native land,
and kept from the use of spirits.  He attributes this, in great part, to
the undoubted fact that the men greatly exceed the women in number; but he
does not know whether this is due to a failure of female offspring, or to
more females dying during early youth.  The latter alternative, according
to all analogy, is very improbable.  He adds that "infanticide, properly so
called, is not common, though very frequent recourse is had to abortion."
If Dr. Coulter is correct about infanticide, this case cannot be advanced
in support of Colonel Marshall's view.  From the rapid decrease of the
reclaimed natives, we may suspect that, as in the cases lately given, their
fertility has been diminished from changed habits of life.

I had hoped to gain some light on this subject from the breeding of dogs;
inasmuch as in most breeds, with the exception, perhaps, of greyhounds,
many more female puppies are destroyed than males, just as with the Toda
infants.  Mr. Cupples assures me that this is usual with Scotch deer-
hounds.  Unfortunately, I know nothing of the proportion of the sexes in
any breed, excepting greyhounds, and there the male births are to the
females as 110.1 to 100.  Now from enquiries made from many breeders, it
seems that the females are in some respects more esteemed, though otherwise
troublesome; and it does not appear that the female puppies of the best-
bred dogs are systematically destroyed more than the males, though this
does sometimes take place to a limited extent.  Therefore I am unable to
decide whether we can, on the above principles, account for the
preponderance of male births in greyhounds.  On the other hand, we have
seen that with horses, cattle, and sheep, which are too valuable for the
young of either sex to be destroyed, if there is any difference, the
females are slightly in excess.)

From the several foregoing cases we have some reason to believe that
infanticide practised in the manner above explained, tends to make a male-
producing race; but I am far from supposing that this practice in the case
of man, or some analogous process with other species, has been the sole
determining cause of an excess of males.  There may be some unknown law
leading to this result in decreasing races, which have already become
somewhat infertile.  Besides the several causes previously alluded to, the
greater facility of parturition amongst savages, and the less consequent
injury to their male infants, would tend to increase the proportion of
live-born males to females.  There does not, however, seem to be any
necessary connection between savage life and a marked excess of males; that
is if we may judge by the character of the scanty offspring of the lately
existing Tasmanians and of the crossed offspring of the Tahitians now
inhabiting Norfolk Island.

As the males and females of many animals differ somewhat in habits and are
exposed in different degrees to danger, it is probable that in many cases,
more of one sex than of the other are habitually destroyed.  But as far as
I can trace out the complication of causes, an indiscriminate though large
destruction of either sex would not tend to modify the sex-producing power
of the species.  With strictly social animals, such as bees or ants, which
produce a vast number of sterile and fertile females in comparison with the
males, and to whom this preponderance is of paramount importance, we can
see that those communities would flourish best which contained females
having a strong inherited tendency to produce more and more females; and in
such cases an unequal sex-producing tendency would be ultimately gained
through natural selection.  With animals living in herds or troops, in
which the males come to the front and defend the herd, as with the bisons
of North America and certain baboons, it is conceivable that a male-
producing tendency might be gained by natural selection; for the
individuals of the better defended herds would leave more numerous
descendants.  In the case of mankind the advantage arising from having a
preponderance of men in the tribe is supposed to be one chief cause of the
practice of female infanticide.

In no case, as far as we can see, would an inherited tendency to produce
both sexes in equal numbers or to produce one sex in excess, be a direct
advantage or disadvantage to certain individuals more than to others; for
instance, an individual with a tendency to produce more males than females
would not succeed better in the battle for life than an individual with an
opposite tendency; and therefore a tendency of this kind could not be
gained through natural selection.  Nevertheless, there are certain animals
(for instance, fishes and cirripedes) in which two or more males appear to
be necessary for the fertilisation of the female; and the males accordingly
largely preponderate, but it is by no means obvious how this male-producing
tendency could have been acquired.  I formerly thought that when a tendency
to produce the two sexes in equal numbers was advantageous to the species,
it would follow from natural selection, but I now see that the whole
problem is so intricate that it is safer to leave its solution for the
future.


CHAPTER IX.

SECONDARY SEXUAL CHARACTERS IN THE LOWER CLASSES OF THE ANIMAL KINGDOM.

These characters absent in the lowest classes--Brilliant colours--Mollusca
--Annelids--Crustacea, secondary sexual characters strongly developed;
dimorphism; colour; characters not acquired before maturity--Spiders,
sexual colours of; stridulation by the males--Myriapoda.

With animals belonging to the lower classes, the two sexes are not rarely
united in the same individual, and therefore secondary sexual characters
cannot be developed.  In many cases where the sexes are separate, both are
permanently attached to some support, and the one cannot search or struggle
for the other.  Moreover it is almost certain that these animals have too
imperfect senses and much too low mental powers to appreciate each other's
beauty or other attractions, or to feel rivalry.

Hence in these classes or sub-kingdoms, such as the Protozoa, Coelenterata,
Echinodermata, Scolecida, secondary sexual characters, of the kind which we
have to consider, do not occur:  and this fact agrees with the belief that
such characters in the higher classes have been acquired through sexual
selection, which depends on the will, desire, and choice of either sex.
Nevertheless some few apparent exceptions occur; thus, as I hear from Dr.
Baird, the males of certain Entozoa, or internal parasitic worms, differ
slightly in colour from the females; but we have no reason to suppose that
such differences have been augmented through sexual selection.
Contrivances by which the male holds the female, and which are
indispensable for the propagation of the species, are independent of sexual
selection, and have been acquired through ordinary selection.

Many of the lower animals, whether hermaphrodites or with separate sexes,
are ornamented with the most brilliant tints, or are shaded and striped in
an elegant manner; for instance, many corals and sea-anemones (Actiniae),
some jelly-fish (Medusae, Porpita, etc.), some Planariae, many star-fishes,
Echini, Ascidians, etc.; but we may conclude from the reasons already
indicated, namely, the union of the two sexes in some of these animals, the
permanently affixed condition of others, and the low mental powers of all,
that such colours do not serve as a sexual attraction, and have not been
acquired through sexual selection.  It should be borne in mind that in no
case have we sufficient evidence that colours have been thus acquired,
except where one sex is much more brilliantly or conspicuously coloured
than the other, and where there is no difference in habits between the
sexes sufficient to account for their different colours.  But the evidence
is rendered as complete as it can ever be, only when the more ornamented
individuals, almost always the males, voluntarily display their attractions
before the other sex; for we cannot believe that such display is useless,
and if it be advantageous, sexual selection will almost inevitably follow.
We may, however, extend this conclusion to both sexes, when coloured alike,
if their colours are plainly analogous to those of one sex alone in certain
other species of the same group.

How, then, are we to account for the beautiful or even gorgeous colours of
many animals in the lowest classes?  It appears doubtful whether such
colours often serve as a protection; but that we may easily err on this
head, will be admitted by every one who reads Mr. Wallace's excellent essay
on this subject.  It would not, for instance, at first occur to any one
that the transparency of the Medusae, or jelly-fish, is of the highest
service to them as a protection; but when we are reminded by Haeckel that
not only the Medusae, but many floating Mollusca, crustaceans, and even
small oceanic fishes partake of this same glass-like appearance, often
accompanied by prismatic colours, we can hardly doubt that they thus escape
the notice of pelagic birds and other enemies.  M. Giard is also convinced
(1.  'Archives de Zoolog. Exper.' Oct. 1872, p. 563.) that the bright tints
of certain sponges and ascidians serve as a protection.  Conspicuous
colours are likewise beneficial to many animals as a warning to their
would-be devourers that they are distasteful, or that they possess some
special means of defence; but this subject will be discussed more
conveniently hereafter.

We can, in our ignorance of most of the lowest animals, only say that their
bright tints result either from the chemical nature or the minute structure
of their tissues, independently of any benefit thus derived.  Hardly any
colour is finer than that of arterial blood; but there is no reason to
suppose that the colour of the blood is in itself any advantage; and though
it adds to the beauty of the maiden's cheek, no one will pretend that it
has been acquired for this purpose.  So again with many animals, especially
the lower ones, the bile is richly coloured; thus, as I am informed by Mr.
Hancock, the extreme beauty of the Eolidae (naked sea-slugs) is chiefly due
to the biliary glands being seen through the translucent integuments--this
beauty being probably of no service to these animals.  The tints of the
decaying leaves in an American forest are described by every one as
gorgeous; yet no one supposes that these tints are of the least advantage
to the trees.  Bearing in mind how many substances closely analogous to
natural organic compounds have been recently formed by chemists, and which
exhibit the most splendid colours, it would have been a strange fact if
substances similarly coloured had not often originated, independently of
any useful end thus gained, in the complex laboratory of living organisms.

THE SUB-KINGDOM OF THE MOLLUSCA.

Throughout this great division of the animal kingdom, as far as I can
discover, secondary sexual characters, such as we are here considering,
never occur.  Nor could they be expected in the three lowest classes,
namely, in the Ascidians, Polyzoa, and Brachiopods (constituting the
Molluscoida of some authors), for most of these animals are permanently
affixed to a support or have their sexes united in the same individual.  In
the Lamellibranchiata, or bivalve shells, hermaphroditism is not rare.  In
the next higher class of the Gasteropoda, or univalve shells, the sexes are
either united or separate.  But in the latter case the males never possess
special organs for finding, securing, or charming the females, or for
fighting with other males.  As I am informed by Mr. Gwyn Jeffreys, the sole
external difference between the sexes consists in the shell sometimes
differing a little in form; for instance, the shell of the male periwinkle
(Littorina littorea) is narrower and has a more elongated spire than that
of the female.  But differences of this nature, it may be presumed, are
directly connected with the act of reproduction, or with the development of
the ova.

The Gasteropoda, though capable of locomotion and furnished with imperfect
eyes, do not appear to be endowed with sufficient mental powers for the
members of the same sex to struggle together in rivalry, and thus to
acquire secondary sexual characters.  Nevertheless with the pulmoniferous
gasteropods, or land-snails, the pairing is preceded by courtship; for
these animals, though hermaphrodites, are compelled by their structure to
pair together.  Agassiz remarks, "Quiconque a eu l'occasion d'observer les
amours des limacons, ne saurait mettre en doute la seduction deployee dans
les mouvements et les allures qui preparent et accomplissent le double
embrassement de ces hermaphrodites."  (2.  'De l'Espece et de la Class.'
etc., 1869, p. 106.)  These animals appear also susceptible of some degree
of permanent attachment:  an accurate observer, Mr. Lonsdale, informs me
that he placed a pair of land-snails, (Helix pomatia), one of which was
weakly, into a small and ill-provided garden.  After a short time the
strong and healthy individual disappeared, and was traced by its track of
slime over a wall into an adjoining well-stocked garden.  Mr. Lonsdale
concluded that it had deserted its sickly mate; but after an absence of
twenty-four hours it returned, and apparently communicated the result of
its successful exploration, for both then started along the same track and
disappeared over the wall.

Even in the highest class of the Mollusca, the Cephalopoda or cuttle-
fishes, in which the sexes are separate, secondary sexual characters of the
present kind do not, as far as I can discover, occur.  This is a surprising
circumstance, as these animals possess highly-developed sense-organs and
have considerable mental powers, as will be admitted by every one who has
watched their artful endeavours to escape from an enemy.  (3.  See, for
instance, the account which I have given in my 'Journal of Researches,'
1845, p. 7.)  Certain Cephalopoda, however, are characterised by one
extraordinary sexual character, namely that the male element collects
within one of the arms or tentacles, which is then cast off, and clinging
by its sucking-discs to the female, lives for a time an independent life.
So completely does the cast-off arm resemble a separate animal, that it was
described by Cuvier as a parasitic worm under the name of Hectocotyle.  But
this marvellous structure may be classed as a primary rather than as a
secondary sexual character.

Although with the Mollusca sexual selection does not seem to have come into
play; yet many univalve and bivalve shells, such as volutes, cones,
scallops, etc., are beautifully coloured and shaped.  The colours do not
appear in most cases to be of any use as a protection; they are probably
the direct result, as in the lowest classes, of the nature of the tissues;
the patterns and the sculpture of the shell depending on its manner of
growth.  The amount of light seems to be influential to a certain extent;
for although, as repeatedly stated by Mr. Gwyn Jeffreys, the shells of some
species living at a profound depth are brightly coloured, yet we generally
see the lower surfaces, as well as the parts covered by the mantle, less
highly-coloured than the upper and exposed surfaces.  (4.  I have given
('Geological Observations on Volcanic Islands,' 1844, p. 53) a curious
instance of the influence of light on the colours of a frondescent
incrustation, deposited by the surf on the coast-rocks of Ascension and
formed by the solution of triturated sea-shells.) In some cases, as with
shells living amongst corals or brightly-tinted seaweeds, the bright
colours may serve as a protection.  (5.  Dr. Morse has lately discussed
this subject in his paper on the 'Adaptive Coloration of Mollusca,' 'Proc.
Boston Soc. of Nat. Hist.' vol. xiv. April 1871.)  But that many of the
nudibranch Mollusca, or sea-slugs, are as beautifully coloured as any
shells, may be seen in Messrs.  Alder and Hancock's magnificent work; and
from information kindly given me by Mr. Hancock, it seems extremely
doubtful whether these colours usually serve as a protection.  With some
species this may be the case, as with one kind which lives on the green
leaves of algae, and is itself bright-green.  But many brightly-coloured,
white, or otherwise conspicuous species, do not seek concealment; whilst
again some equally conspicuous species, as well as other dull-coloured
kinds live under stones and in dark recesses.  So that with these
nudibranch molluscs, colour apparently does not stand in any close relation
to the nature of the places which they inhabit.

These naked sea-slugs are hermaphrodites, yet they pair together, as do
land-snails, many of which have extremely pretty shells.  It is conceivable
that two hermaphrodites, attracted by each other's greater beauty, might
unite and leave offspring which would inherit their parents' greater
beauty.  But with such lowly-organised creatures this is extremely
improbable.  Nor is it at all obvious how the offspring from the more
beautiful pairs of hermaphrodites would have any advantage over the
offspring of the less beautiful, so as to increase in number, unless indeed
vigour and beauty generally coincided.  We have not here the case of a
number of males becoming mature before the females, with the more beautiful
males selected by the more vigorous females.  If, indeed, brilliant colours
were beneficial to a hermaphrodite animal in relation to its general habits
of life, the more brightly-tinted individuals would succeed best and would
increase in number; but this would be a case of natural and not of sexual
selection.

SUB-KINGDOM OF THE VERMES:  CLASS, ANNELIDA (OR SEA-WORMS).

In this class, although the sexes, when separate, sometimes differ from
each other in characters of such importance that they have been placed
under distinct genera or even families, yet the differences do not seem of
the kind which can be safely attributed to sexual selection.  These animals
are often beautifully coloured, but as the sexes do not differ in this
respect, we are but little concerned with them.  Even the Nemertians,
though so lowly organised, "vie in beauty and variety of colouring with any
other group in the invertebrate series"; yet Dr. McIntosh (6.  See his
beautiful monograph on 'British Annelids,' part i. 1873, p. 3.) cannot
discover that these colours are of any service.  The sedentary annelids
become duller-coloured, according to M. Quatrefages (7.  See M. Perrier:
'L'Origine de l'Homme d'apres Darwin,' 'Revue Scientifique', Feb. 1873, p.
866.), after the period of reproduction; and this I presume may be
attributed to their less vigorous condition at that time.  All these worm-
like animals apparently stand too low in the scale for the individuals of
either sex to exert any choice in selecting a partner, or for the
individuals of the same sex to struggle together in rivalry.

SUB-KINGDOM OF THE ARTHROPODA:  CLASS, CRUSTACEA.

In this great class we first meet with undoubted secondary sexual
characters, often developed in a remarkable manner.  Unfortunately the
habits of crustaceans are very imperfectly known, and we cannot explain the
uses of many structures peculiar to one sex.  With the lower parasitic
species the males are of small size, and they alone are furnished with
perfect swimming-legs, antennae and sense-organs; the females being
destitute of these organs, with their bodies often consisting of a mere
distorted mass.  But these extraordinary differences between the two sexes
are no doubt related to their widely different habits of life, and
consequently do not concern us.  In various crustaceans, belonging to
distinct families, the anterior antennae are furnished with peculiar
thread-like bodies, which are believed to act as smelling-organs, and these
are much more numerous in the males than in the females.  As the males,
without any unusual development of their olfactory organs, would almost
certainly be able sooner or later to find the females, the increased number
of the smelling-threads has probably been acquired through sexual
selection, by the better provided males having been the more successful in
finding partners and in producing offspring.  Fritz Mueller has described a
remarkable dimorphic species of Tanais, in which the male is represented by
two distinct forms, which never graduate into each other.  In the one form
the male is furnished with more numerous smelling-threads, and in the other
form with more powerful and more elongated chelae or pincers, which serve
to hold the female.  Fritz Mueller suggests that these differences between
the two male forms of the same species may have originated in certain
individuals having varied in the number of the smelling-threads, whilst
other individuals varied in the shape and size of their chelae; so that of
the former, those which were best able to find the female, and of the
latter, those which were best able to hold her, have left the greatest
number of progeny to inherit their respective advantages.  (8.  'Facts and
Arguments for Darwin,' English translat., 1869, p. 20.  See the previous
discussion on the olfactory threads.  Sars has described a somewhat
analogous case (as quoted in 'Nature,' 1870, p. 455) in a Norwegian
crustacean, the Pontoporeia affinis.)

[Fig.4.  Labidocera Darwinii (from Lubbock).  Labelled are:
a.  Part of right anterior antenna of male, forming a prehensile organ.
b.  Posterior pair of thoracic legs of male.
c.  Ditto of female.]

In some of the lower crustaceans, the right anterior antenna of the male
differs greatly in structure from the left, the latter resembling in its
simple tapering joints the antennae of the female.  In the male the
modified antenna is either swollen in the middle or angularly bent, or
converted (Fig. 4) into an elegant, and sometimes wonderfully complex,
prehensile organ.  (9.  See Sir J. Lubbock in 'Annals and Mag. of Nat.
Hist.' vol. xi. 1853, pl. i. and x.; and vol. xii. (1853), pl. vii.  See
also Lubbock in 'Transactions, Entomological Society,' vol. iv. new series,
1856-1858, p. 8.  With respect to the zigzagged antennae mentioned below,
see Fritz Mueller, 'Facts and Arguments for Darwin,' 1869, p. 40, foot-
note.)  It serves, as I hear from Sir J. Lubbock, to hold the female, and
for this same purpose one of the two posterior legs (b) on the same side of
the body is converted into a forceps.  In another family the inferior or
posterior antennae are "curiously zigzagged" in the males alone.

[Fig. 5.  Anterior part of body of Callianassa (from Milne-Edwards),
showing the unequal and differently-constructed right and left-hand chelae
of the male.  N.B.--The artist by mistake has reversed the drawing, and
made the left-hand chela the largest.

Fig. 6.  Second leg of male Orchestia Tucuratinga (from Fritz Mueller).

Fig. 7.  Ditto of female.]

In the higher crustaceans the anterior legs are developed into chelae or
pincers; and these are generally larger in the male than in the female,--so
much so that the market value of the male edible crab (Cancer pagurus),
according to Mr. C. Spence Bate, is five times as great as that of the
female.  In many species the chelae are of unequal size on the opposite
side of the body, the right-hand one being, as I am informed by Mr. Bate,
generally, though not invariably, the largest.  This inequality is also
often much greater in the male than in the female.  The two chelae of the
male often differ in structure (Figs. 5, 6, and 7), the smaller one
resembling that of the female.  What advantage is gained by their
inequality in size on the opposite sides of the body, and by the inequality
being much greater in the male than in the female; and why, when they are
of equal size, both are often much larger in the male than in the female,
is not known.  As I hear from Mr. Bate, the chelae are sometimes of such
length and size that they cannot possibly be used for carrying food to the
mouth.  In the males of certain fresh-water prawns (Palaemon) the right leg
is actually longer than the whole body.  (10.  See a paper by Mr. C. Spence
Bate, with figures, in 'Proceedings, Zoological Society,' 1868, p. 363; and
on the nomenclature of the genus, ibid. p. 585.  I am greatly indebted to
Mr. Spence Bate for nearly all the above statements with respect to the
chelae of the higher crustaceans.)  The great size of the one leg with its
chelae may aid the male in fighting with his rivals; but this will not
account for their inequality in the female on the opposite sides of the
body.  In Gelasimus, according to a statement quoted by Milne Edwards (11.
'Hist. Nat. des Crust.' tom. ii. 1837, p. 50.), the male and the female
live in the same burrow, and this shews that they pair; the male closes the
mouth of the burrow with one of its chelae, which is enormously developed;
so that here it indirectly serves as a means of defence.  Their main use,
however, is probably to seize and to secure the female, and this in some
instances, as with Gammarus, is known to be the case.  The male of the
hermit or soldier crab (Pagurus) for weeks together, carries about the
shell inhabited by the female.  (12.  Mr. C. Spence Bate, 'British
Association, Fourth Report on the Fauna of S. Devon.')  The sexes, however,
of the common shore-crab (Carcinus maenas), as Mr. Bate informs me, unite
directly after the female has moulted her hard shell, when she is so soft
that she would be injured if seized by the strong pincers of the male; but
as she is caught and carried about by the male before moulting, she could
then be seized with impunity.

[Fig.8.  Orchestia Darwinii (from Fritz Mueller), showing the differently-
constructed chelae of the two male forms.]

Fritz Mueller states that certain species of Melita are distinguished from
all other amphipods by the females having "the coxal lamellae of the
penultimate pair of feet produced into hook-like processes, of which the
males lay hold with the hands of the first pair."  The development of these
hook-like processes has probably followed from those females which were the
most securely held during the act of reproduction, having left the largest
number of offspring.  Another Brazilian amphipod (see Orchestia darwinii,
Fig. 8) presents a case of dimorphism, like that of Tanais; for there are
two male forms, which differ in the structure of their chelae.  (13.  Fritz
Mueller, 'Facts and Arguments for Darwin,' 1869, pp. 25-28.)  As either
chela would certainly suffice to hold the female,--for both are now used
for this purpose,--the two male forms probably originated by some having
varied in one manner and some in another; both forms having derived certain
special, but nearly equal advantages, from their differently shaped organs.

It is not known that male crustaceans fight together for the possession of
the females, but it is probably the case; for with most animals when the
male is larger than the female, he seems to owe his greater size to his
ancestors having fought with other males during many generations.  In most
of the orders, especially in the highest or the Brachyura, the male is
larger than the female; the parasitic genera, however, in which the sexes
follow different habits of life, and most of the Entomostraca must be
excepted.  The chelae of many crustaceans are weapons well adapted for
fighting.  Thus when a Devil-crab (Portunus puber) was seen by a son of Mr.
Bate fighting with a Carcinus maenas, the latter was soon thrown on its
back, and had every limb torn from its body.  When several males of a
Brazilian Gelasimus, a species furnished with immense pincers, were placed
together in a glass vessel by Fritz Mueller, they mutilated and killed one
another.  Mr. Bate put a large male Carcinus maenas into a pan of water,
inhabited by a female which was paired with a smaller male; but the latter
was soon dispossessed.  Mr. Bate adds, "if they fought, the victory was a
bloodless one, for I saw no wounds."  This same naturalist separated a male
sand-skipper (so common on our sea-shores), Gammarus marinus, from its
female, both of whom were imprisoned in the same vessel with many
individuals of the same species.  The female, when thus divorced, soon
joined the others.  After a time the male was put again into the same
vessel; and he then, after swimming about for a time, dashed into the
crowd, and without any fighting at once took away his wife.  This fact
shews that in the Amphipoda, an order low in the scale, the males and
females recognise each other, and are mutually attached.

The mental powers of the Crustacea are probably higher than at first sight
appears probable.  Any one who tries to catch one of the shore-crabs, so
common on tropical coasts, will perceive how wary and alert they are.
There is a large crab (Birgus latro), found on coral islands, which makes a
thick bed of the picked fibres of the cocoa-nut, at the bottom of a deep
burrow.  It feeds on the fallen fruit of this tree by tearing off the husk,
fibre by fibre; and it always begins at that end where the three eye-like
depressions are situated.  It then breaks through one of these eyes by
hammering with its heavy front pincers, and turning round, extracts the
albuminous core with its narrow posterior pincers.  But these actions are
probably instinctive, so that they would be performed as well by a young
animal as by an old one.  The following case, however, can hardly be so
considered:  a trustworthy naturalist, Mr. Gardner (14.  'Travels in the
Interior of Brazil,' 1846, p. 111.  I have given, in my 'Journal of
Researches,' p. 463, an account of the habits of the Birgus.), whilst
watching a shore-crab (Gelasimus) making its burrow, threw some shells
towards the hole.  One rolled in, and three other shells remained within a
few inches of the mouth.  In about five minutes the crab brought out the
shell which had fallen in, and carried it away to a distance of a foot; it
then saw the three other shells lying near, and evidently thinking that
they might likewise roll in, carried them to the spot where it had laid the
first.  It would, I think, be difficult to distinguish this act from one
performed by man by the aid of reason.

Mr. Bate does not know of any well-marked case of difference of colour in
the two sexes of our British crustaceans, in which respect the sexes of the
higher animals so often differ.  In some cases, however, the males and
females differ slightly in tint, but Mr. Bate thinks not more than may be
accounted for by their different habits of life, such as by the male
wandering more about, and being thus more exposed to the light.  Dr. Power
tried to distinguish by colour the sexes of the several species which
inhabit the Mauritius, but failed, except with one species of Squilla,
probably S. stylifera, the male of which is described as being "of a
beautiful bluish-green," with some of the appendages cherry-red, whilst the
female is clouded with brown and grey, "with the red about her much less
vivid than in the male."  (15.  Mr. Ch. Fraser, in 'Proc. Zoolog. Soc.'
1869, p. 3.  I am indebted to Mr. Bate for Dr. Power's statement.)  In this
case, we may suspect the agency of sexual selection.  From M. Bert's
observations on Daphnia, when placed in a vessel illuminated by a prism, we
have reason to believe that even the lowest crustaceans can distinguish
colours.  With Saphirina (an oceanic genus of Entomostraca), the males are
furnished with minute shields or cell-like bodies, which exhibit beautiful
changing colours; these are absent in the females, and in both sexes of one
species.  (16.  Claus, 'Die freilebenden Copepoden,' 1863, s. 35.)  It
would, however, be extremely rash to conclude that these curious organs
serve to attract the females.  I am informed by Fritz Mueller, that in the
female of a Brazilian species of Gelasimus, the whole body is of a nearly
uniform greyish-brown.  In the male the posterior part of the cephalo-
thorax is pure white, with the anterior part of a rich green, shading into
dark brown; and it is remarkable that these colours are liable to change in
the course of a few minutes--the white becoming dirty grey or even black,
the green "losing much of its brilliancy."  It deserves especial notice
that the males do not acquire their bright colours until they become
mature.  They appear to be much more numerous than the females; they differ
also in the larger size of their chelae.  In some species of the genus,
probably in all, the sexes pair and inhabit the same burrow.  They are
also, as we have seen, highly intelligent animals.  From these various
considerations it seems probable that the male in this species has become
gaily ornamented in order to attract or excite the female.

It has just been stated that the male Gelasimus does not acquire his
conspicuous colours until mature and nearly ready to breed.  This seems a
general rule in the whole class in respect to the many remarkable
structural differences between the sexes.  We shall hereafter find the same
law prevailing throughout the great sub-kingdom of the Vertebrata; and in
all cases it is eminently distinctive of characters which have been
acquired through sexual selection.  Fritz Mueller (17.  'Facts and
Arguments,' etc., p. 79.) gives some striking instances of this law; thus
the male sand-hopper (Orchestia) does not, until nearly full grown, acquire
his large claspers, which are very differently constructed from those of
the female; whilst young, his claspers resemble those of the female.

CLASS, ARACHNIDA (SPIDERS).

The sexes do not generally differ much in colour, but the males are often
darker than the females, as may be seen in Mr. Blackwall's magnificent
work.  (18.  'A History of the Spiders of Great Britain,' 1861-64.  For the
following facts, see pp. 77, 88, 102.)  In some species, however, the
difference is conspicuous:  thus the female of Sparassus smaragdulus is
dullish green, whilst the adult male has the abdomen of a fine yellow, with
three longitudinal stripes of rich red.  In certain species of Thomisus the
sexes closely resemble each other, in others they differ much; and
analogous cases occur in many other genera.  It is often difficult to say
which of the two sexes departs most from the ordinary coloration of the
genus to which the species belong; but Mr. Blackwall thinks that, as a
general rule, it is the male; and Canestrini (19.  This author has recently
published a valuable essay on the 'Caratteri sessuali secondarii degli
Arachnidi,' in the 'Atti della Soc. Veneto-Trentina di Sc. Nat. Padova,'
vol. i. Fasc. 3, 1873.) remarks that in certain genera the males can be
specifically distinguished with ease, but the females with great
difficulty.  I am informed by Mr. Blackwall that the sexes whilst young
usually resemble each other; and both often undergo great changes in colour
during their successive moults, before arriving at maturity.  In other
cases the male alone appears to change colour.  Thus the male of the above
bright-coloured Sparassus at first resembles the female, and acquires his
peculiar tints only when nearly adult.  Spiders are possessed of acute
senses, and exhibit much intelligence; as is well known, the females often
shew the strongest affection for their eggs, which they carry about
enveloped in a silken web.  The males search eagerly for the females, and
have been seen by Canestrini and others to fight for possession of them.
This same author says that the union of the two sexes has been observed in
about twenty species; and he asserts positively that the female rejects
some of the males who court her, threatens them with open mandibles, and at
last after long hesitation accepts the chosen one.  From these several
considerations, we may admit with some confidence that the well-marked
differences in colour between the sexes of certain species are the results
of sexual selection; though we have not here the best kind of evidence,--
the display by the male of his ornaments.  From the extreme variability of
colour in the male of some species, for instance of Theridion lineatum, it
would appear that these sexual characters of the males have not as yet
become well fixed.  Canestrini draws the same conclusion from the fact that
the males of certain species present two forms, differing from each other
in the size and length of their jaws; and this reminds us of the above
cases of dimorphic crustaceans.

The male is generally much smaller than the female, sometimes to an
extraordinary degree (20.  Aug. Vinson ('Araneides des Iles de la Reunion,'
pl. vi. figs. 1 and 2) gives a good instance of the small size of the male,
in Epeira nigra.  In this species, as I may add, the male is testaceous and
the female black with legs banded with red.  Other even more striking cases
of inequality in size between the sexes have been recorded ('Quarterly
Journal of Science,' July 1868, p. 429); but I have not seen the original
accounts.), and he is forced to be extremely cautious in making his
advances, as the female often carries her coyness to a dangerous pitch.  De
Geer saw a male that "in the midst of his preparatory caresses was seized
by the object of his attentions, enveloped by her in a web and then
devoured, a sight which, as he adds, filled him with horror and
indignation."  (21.  Kirby and Spence, 'Introduction to Entomology,' vol.
i. 1818, p. 280.)  The Rev. O.P. Cambridge (22.  'Proceedings, Zoological
Society,' 1871, p. 621.) accounts in the following manner for the extreme
smallness of the male in the genus Nephila.  "M. Vinson gives a graphic
account of the agile way in which the diminutive male escapes from the
ferocity of the female, by gliding about and playing hide and seek over her
body and along her gigantic limbs:  in such a pursuit it is evident that
the chances of escape would be in favour of the smallest males, while the
larger ones would fall early victims; thus gradually a diminutive race of
males would be selected, until at last they would dwindle to the smallest
possible size compatible with the exercise of their generative functions,--
in fact, probably to the size we now see them, i.e., so small as to be a
sort of parasite upon the female, and either beneath her notice, or too
agile and too small for her to catch without great difficulty."

Westring has made the interesting discovery that the males of several
species of Theridion (23.  Theridion (Asagena, Sund.) serratipes, 4-
punctatum et guttatum; see Westring, in Kroyer, 'Naturhist. Tidskrift,'
vol. iv. 1842-1843, p. 349; and vol. ii. 1846-1849, p. 342.  See, also, for
other species, 'Araneae Suecicae,' p. 184.) have the power of making a
stridulating sound, whilst the females are mute.  The apparatus consists of
a serrated ridge at the base of the abdomen, against which the hard hinder
part of the thorax is rubbed; and of this structure not a trace can be
detected in the females.  It deserves notice that several writers,
including the well-known arachnologist Walckenaer, have declared that
spiders are attracted by music.  (24.  Dr. H.H. van Zouteveen, in his Dutch
translation of this work (vol. i. p. 444), has collected several cases.)
From the analogy of the Orthoptera and Homoptera, to be described in the
next chapter, we may feel almost sure that the stridulation serves, as
Westring also believes, to call or to excite the female; and this is the
first case known to me in the ascending scale of the animal kingdom of
sounds emitted for this purpose.  (25.  Hilgendorf, however, has lately
called attention to an analogous structure in some of the higher
crustaceans, which seems adapted to produce sound; see 'Zoological Record,'
1869, p. 603.)

CLASS, MYRIAPODA.

In neither of the two orders in this class, the millipedes and centipedes,
can I find any well-marked instances of such sexual differences as more
particularly concern us.  In Glomeris limbata, however, and perhaps in some
few other species, the males differ slightly in colour from the females;
but this Glomeris is a highly variable species.  In the males of the
Diplopoda, the legs belonging either to one of the anterior or of the
posterior segments of the body are modified into prehensile hooks which
serve to secure the female.  In some species of Iulus the tarsi of the male
are furnished with membranous suckers for the same purpose.  As we shall
see when we treat of Insects, it is a much more unusual circumstance, that
it is the female in Lithobius, which is furnished with prehensile
appendages at the extremity of her body for holding the male.  (26.
Walckenaer et P. Gervais, 'Hist. Nat. des Insectes:  Apteres,' tom. iv.
1847, pp. 17, 19, 68.)


CHAPTER X.

SECONDARY SEXUAL CHARACTERS OF INSECTS.

Diversified structures possessed by the males for seizing the females--
Differences between the sexes, of which the meaning is not understood--
Difference in size between the sexes--Thysanura--Diptera--Hemiptera--
Homoptera, musical powers possessed by the males alone--Orthoptera, musical
instruments of the males, much diversified in structure; pugnacity;
colours--Neuroptera, sexual differences in colour--Hymenoptera, pugnacity
and odours--Coleoptera, colours; furnished with great horns, apparently as
an ornament; battles, stridulating organs generally common to both sexes.

In the immense class of insects the sexes sometimes differ in their
locomotive-organs, and often in their sense-organs, as in the pectinated
and beautifully plumose antennae of the males of many species.  In Chloeon,
one of the Ephemerae, the male has great pillared eyes, of which the female
is entirely destitute.  (1.  Sir J. Lubbock, 'Transact. Linnean Soc.' vol.
xxv, 1866, p. 484.  With respect to the Mutillidae see Westwood, 'Modern
Class. of Insects,' vol. ii. p. 213.)  The ocelli are absent in the females
of certain insects, as in the Mutillidae; and here the females are likewise
wingless.  But we are chiefly concerned with structures by which one male
is enabled to conquer another, either in battle or courtship, through his
strength, pugnacity, ornaments, or music.  The innumerable contrivances,
therefore, by which the male is able to seize the female, may be briefly
passed over.  Besides the complex structures at the apex of the abdomen,
which ought perhaps to be ranked as primary organs (2.  These organs in the
male often differ in closely-allied species, and afford excellent specific
characters.  But their importance, from a functional point of view, as Mr.
R. MacLachlan has remarked to me, has probably been overrated.  It has been
suggested, that slight differences in these organs would suffice to prevent
the intercrossing of well-marked varieties or incipient species, and would
thus aid in their development.  That this can hardly be the case, we may
infer from the many recorded cases (see, for instance, Bronn, 'Geschichte
der Natur,' B. ii. 1843, s. 164; and Westwood, 'Transact. Ent. Soc.' vol.
iii. 1842, p. 195) of distinct species having been observed in union.  Mr.
MacLachlan informs me (vide 'Stett. Ent. Zeitung,' 1867, s. 155) that when
several species of Phryganidae, which present strongly-pronounced
differences of this kind, were confined together by Dr. Aug. Meyer, THEY
COUPLED, and one pair produced fertile ova.), "it is astonishing," as Mr.
B.D. Walsh (3.  'The Practical Entomologist,' Philadelphia, vol. ii. May
1867, p. 88.) has remarked, "how many different organs are worked in by
nature for the seemingly insignificant object of enabling the male to grasp
the female firmly."  The mandibles or jaws are sometimes used for this
purpose; thus the male Corydalis cornutus (a neuropterous insect in some
degree allied to the Dragon flies, etc.) has immense curved jaws, many
times longer than those of the female; and they are smooth instead of being
toothed, so that he is thus enabled to seize her without injury.  (4.  Mr.
Walsh, ibid. p. 107.)  One of the stag-beetles of North America (Lucanus
elaphus) uses his jaws, which are much larger than those of the female, for
the same purpose, but probably likewise for fighting.  In one of the sand-
wasps (Ammophila) the jaws in the two sexes are closely alike, but are used
for widely different purposes:  the males, as Professor Westwood observes,
"are exceedingly ardent, seizing their partners round the neck with their
sickle-shaped jaws" (5.  'Modern Classification of Insects,' vol. ii. 1840,
pp. 205, 206.  Mr. Walsh, who called my attention to the double use of the
jaws, says that he has repeatedly observed this fact.); whilst the females
use these organs for burrowing in sand-banks and making their nests.

[Fig. 9. Crabro cribrarius.  Upper figure, male; lower figure, female.]

The tarsi of the front-legs are dilated in many male beetles, or are
furnished with broad cushions of hairs; and in many genera of water-beetles
they are armed with a round flat sucker, so that the male may adhere to the
slippery body of the female.  It is a much more unusual circumstance that
the females of some water-beetles (Dytiscus) have their elytra deeply
grooved, and in Acilius sulcatus thickly set with hairs, as an aid to the
male.  The females of some other water-beetles (Hydroporus) have their
elytra punctured for the same purpose.  (6.  We have here a curious and
inexplicable case of dimorphism, for some of the females of four European
species of Dytiscus, and of certain species of Hydroporus, have their
elytra smooth; and no intermediate gradations between the sulcated or
punctured, and the quite smooth elytra have been observed.  See Dr. H.
Schaum, as quoted in the 'Zoologist,' vols. v.-vi. 1847-48, p. 1896.  Also
Kirby and Spence, 'Introduction to Entomology,' vol. iii. 1826, p. 305.)
In the male of Crabro cribrarius (Fig. 9), it is the tibia which is dilated
into a broad horny plate, with minute membraneous dots, giving to it a
singular appearance like that of a riddle.  (7.  Westwood, 'Modern Class.'
vol. ii. p. 193.  The following statement about Penthe, and others in
inverted commas, are taken from Mr. Walsh, 'Practical Entomologist,'
Philadelphia, vol. iii. p. 88.)  In the male of Penthe (a genus of beetles)
a few of the middle joints of the antennae are dilated and furnished on the
inferior surface with cushions of hair, exactly like those on the tarsi of
the Carabidae, "and obviously for the same end."  In male dragon-flies,
"the appendages at the tip of the tail are modified in an almost infinite
variety of curious patterns to enable them to embrace the neck of the
female."  Lastly, in the males of many insects, the legs are furnished with
peculiar spines, knobs or spurs; or the whole leg is bowed or thickened,
but this is by no means invariably a sexual character; or one pair, or all
three pairs are elongated, sometimes to an extravagant length. (8.  Kirby
and Spence, 'Introduct.' etc., vol. iii. pp. 332-336.)

[Fig. 10.  Taphroderes distortus (much enlarged).  Upper figure, male;
lower figure, female.]

The sexes of many species in all the orders present differences, of which
the meaning is not understood.  One curious case is that of a beetle (Fig.
10), the male of which has left mandible much enlarged; so that the mouth
is greatly distorted.  In another Carabidous beetle, Eurygnathus (9.
'Insecta Maderensia,' 1854, page 20.), we have the case, unique as far as
known to Mr. Wollaston, of the head of the female being much broader and
larger, though in a variable degree, than that of the male.  Any number of
such cases could be given.  They abound in the Lepidoptera:  one of the
most extraordinary is that certain male butterflies have their fore-legs
more or less atrophied, with the tibiae and tarsi reduced to mere
rudimentary knobs.  The wings, also, in the two sexes often differ in
neuration (10.  E. Doubleday, 'Annals and Mag. of Nat. Hist.' vol. i. 1848,
p. 379.  I may add that the wings in certain Hymenoptera (see Shuckard,
'Fossorial Hymenoptera,' 1837, pp. 39-43) differ in neuration according to
sex.), and sometimes considerably in outline, as in the Aricoris epitus,
which was shewn to me in the British Museum by Mr. A. Butler.  The males of
certain South American butterflies have tufts of hair on the margins of the
wings, and horny excrescences on the discs of the posterior pair.  (11.
H.W. Bates, in 'Journal of Proc. Linn. Soc.' vol. vi. 1862, p. 74.  Mr.
Wonfor's observations are quoted in 'Popular Science Review,' 1868, p.
343.)  In several British butterflies, as shewn by Mr. Wonfor, the males
alone are in parts clothed with peculiar scales.

The use of the bright light of the female glow-worm has been subject to
much discussion.  The male is feebly luminous, as are the larvae and even
the eggs.  It has been supposed by some authors that the light serves to
frighten away enemies, and by others to guide the male to the female.  At
last, Mr. Belt (12.  'The Naturalist in Nicaragua,' 1874, pp. 316-320.  On
the phosphorescence of the eggs, see 'Annals and Magazine of Natural
History,' Nov. 1871, p. 372.) appears to have solved the difficulty:  he
finds that all the Lampyridae which he has tried are highly distasteful to
insectivorous mammals and birds.  Hence it is in accordance with Mr. Bates'
view, hereafter to be explained, that many insects mimic the Lampyridae
closely, in order to be mistaken for them, and thus to escape destruction.
He further believes that the luminous species profit by being at once
recognised as unpalatable.  It is probable that the same explanation may be
extended to the Elaters, both sexes of which are highly luminous.  It is
not known why the wings of the female glow-worm have not been developed;
but in her present state she closely resembles a larva, and as larvae are
so largely preyed on by many animals, we can understand why she has been
rendered so much more luminous and conspicuous than the male; and why the
larvae themselves are likewise luminous.

DIFFERENCE IN SIZE BETWEEN THE SEXES.

With insects of all kinds the males are commonly smaller than the females;
and this difference can often be detected even in the larval state.  So
considerable is the difference between the male and female cocoons of the
silk-moth (Bombyx mori), that in France they are separated by a particular
mode of weighing.  (13.  Robinet, 'Vers a Soie,' 1848, p. 207.)  In the
lower classes of the animal kingdom, the greater size of the females seems
generally to depend on their developing an enormous number of ova; and this
may to a certain extent hold good with insects.  But Dr. Wallace has
suggested a much more probable explanation.  He finds, after carefully
attending to the development of the caterpillars of Bombyx cynthia and
yamamai, and especially to that of some dwarfed caterpillars reared from a
second brood on unnatural food, "that in proportion as the individual moth
is finer, so is the time required for its metamorphosis longer; and for
this reason the female, which is the larger and heavier insect, from having
to carry her numerous eggs, will be preceded by the male, which is smaller
and has less to mature."  (14.  'Transact. Ent. Soc.' 3rd series, vol. v.
p. 486.)  Now as most insects are short-lived, and as they are exposed to
many dangers, it would manifestly be advantageous to the female to be
impregnated as soon as possible.  This end would be gained by the males
being first matured in large numbers ready for the advent of the females;
and this again would naturally follow, as Mr. A.R. Wallace has remarked
(15.  'Journal of Proc. Ent. Soc.' Feb. 4, 1867, p. lxxi.), through natural
selection; for the smaller males would be first matured, and thus would
procreate a large number of offspring which would inherit the reduced size
of their male parents, whilst the larger males from being matured later
would leave fewer offspring.

There are, however, exceptions to the rule of male insects being smaller
than the females:  and some of these exceptions are intelligible.  Size and
strength would be an advantage to the males, which fight for the possession
of the females; and in these cases, as with the stag-beetle (Lucanus), the
males are larger than the females.  There are, however, other beetles which
are not known to fight together, of which the males exceed the females in
size; and the meaning of this fact is not known; but in some of these
cases, as with the huge Dynastes and Megasoma, we can at least see that
there would be no necessity for the males to be smaller than the females,
in order to be matured before them, for these beetles are not short-lived,
and there would be ample time for the pairing of the sexes.  So again, male
dragon-flies (Libellulidae) are sometimes sensibly larger, and never
smaller, than the females (16.  For this and other statements on the size
of the sexes, see Kirby and Spence, ibid. vol. iii. p. 300; on the duration
of life in insects, see p. 344.); and as Mr. MacLachlan believes, they do
not generally pair with the females until a week or fortnight has elapsed,
and until they have assumed their proper masculine colours.  But the most
curious case, shewing on what complex and easily-overlooked relations, so
trifling a character as difference in size between the sexes may depend, is
that of the aculeate Hymenoptera; for Mr. F. Smith informs me that
throughout nearly the whole of this large group, the males, in accordance
with the general rule, are smaller than the females, and emerge about a
week before them; but amongst the Bees, the males of Apis mellifica,
Anthidium manicatum, and Anthophora acervorum, and amongst the Fossores,
the males of the Methoca ichneumonides, are larger than the females.  The
explanation of this anomaly is that a marriage flight is absolutely
necessary with these species, and the male requires great strength and size
in order to carry the female through the air.  Increased size has here been
acquired in opposition to the usual relation between size and the period of
development, for the males, though larger, emerge before the smaller
females.

We will now review the several Orders, selecting such facts as more
particularly concern us.  The Lepidoptera (Butterflies and Moths) will be
retained for a separate chapter.

ORDER, THYSANURA.

The members of this lowly organised order are wingless, dull-coloured,
minute insects, with ugly, almost misshapen heads and bodies.  Their sexes
do not differ, but they are interesting as shewing us that the males pay
sedulous court to the females even low down in the animal scale.  Sir J.
Lubbock (17.  'Transact. Linnean Soc.' vol. xxvi. 1868, p. 296.) says:  "it
is very amusing to see these little creatures (Smynthurus luteus)
coquetting together.  The male, which is much smaller than the female, runs
round her, and they butt one another, standing face to face and moving
backward and forward like two playful lambs.  Then the female pretends to
run away and the male runs after her with a queer appearance of anger, gets
in front and stands facing her again; then she turns coyly round, but he,
quicker and more active, scuttles round too, and seems to whip her with his
antennae; then for a bit they stand face to face, play with their antennae,
and seem to be all in all to one another."

ORDER, DIPTERA (FLIES).

The sexes differ little in colour.  The greatest difference, known to Mr.
F. Walker, is in the genus Bibio, in which the males are blackish or quite
black, and the females obscure brownish-orange.  The genus Elaphomyia,
discovered by Mr. Wallace (18.  'The Malay Archipelago,' vol. ii. 1869, p.
313.) in New Guinea, is highly remarkable, as the males are furnished with
horns, of which the females are quite destitute.  The horns spring from
beneath the eyes, and curiously resemble those of a stag, being either
branched or palmated.  In one of the species, they equal the whole body in
length.  They might be thought to be adapted for fighting, but as in one
species they are of a beautiful pink colour, edged with black, with a pale
central stripe, and as these insects have altogether a very elegant
appearance, it is perhaps more probable that they serve as ornaments.  That
the males of some Diptera fight together is certain; Prof. Westwood (19.
'Modern Classification of Insects,' vol. ii. 1840, p. 526.) has several
times seen this with the Tipulae.  The males of other Diptera apparently
try to win the females by their music:  H. Mueller (20.  'Anwendung,' etc.,
'Verh. d. n. V. Jahrg.' xxix. p. 80.  Mayer, in 'American Naturalist,'
1874, p. 236.) watched for some time two males of an Eristalis courting a
female; they hovered above her, and flew from side to side, making a high
humming noise at the same time.  Gnats and mosquitoes (Culicidae) also seem
to attract each other by humming; and Prof. Mayer has recently ascertained
that the hairs on the antennae of the male vibrate in unison with the notes
of a tuning-fork, within the range of the sounds emitted by the female.
The longer hairs vibrate sympathetically with the graver notes, and the
shorter hairs with the higher ones.  Landois also asserts that he has
repeatedly drawn down a whole swarm of gnats by uttering a particular note.
It may be added that the mental faculties of the Diptera are probably
higher than in most other insects, in accordance with their highly-
developed nervous system.  (21.  See Mr. B.T. Lowne's interesting work, 'On
the Anatomy of the Blow-fly, Musca vomitoria,' 1870, p. 14.  He remarks (p.
33) that, "the captured flies utter a peculiar plaintive note, and that
this sound causes other flies to disappear.")

ORDER, HEMIPTERA (FIELD-BUGS).

Mr. J.W. Douglas, who has particularly attended to the British species, has
kindly given me an account of their sexual differences.  The males of some
species are furnished with wings, whilst the females are wingless; the
sexes differ in the form of their bodies, elytra, antennae and tarsi; but
as the signification of these differences are unknown, they may be here
passed over.  The females are generally larger and more robust than the
males.  With British, and, as far as Mr. Douglas knows, with exotic
species, the sexes do not commonly differ much in colour; but in about six
British species the male is considerably darker than the female, and in
about four other species the female is darker than the male.  Both sexes of
some species are beautifully coloured; and as these insects emit an
extremely nauseous odour, their conspicuous colours may serve as a signal
that they are unpalatable to insectivorous animals.  In some few cases
their colours appear to be directly protective:  thus Prof. Hoffmann
informs me that he could hardly distinguish a small pink and green species
from the buds on the trunks of lime-trees, which this insect frequents.

Some species of Reduvidae make a stridulating noise; and, in the case of
Pirates stridulus, this is said (22.  Westwood, 'Modern Classification of
Insects,' vol. ii. p. 473.) to be effected by the movement of the neck
within the pro-thoracic cavity.  According to Westring, Reduvius personatus
also stridulates.  But I have no reason to suppose that this is a sexual
character, excepting that with non-social insects there seems to be no use
for sound-producing organs, unless it be as a sexual call.

ORDER:  HOMOPTERA.

Every one who has wandered in a tropical forest must have been astonished
at the din made by the male Cicadae.  The females are mute; as the Grecian
poet Xenarchus says, "Happy the Cicadas live, since they all have voiceless
wives."  The noise thus made could be plainly heard on board the "Beagle,"
when anchored at a quarter of a mile from the shore of Brazil; and Captain
Hancock says it can be heard at the distance of a mile.  The Greeks
formerly kept, and the Chinese now keep these insects in cages for the sake
of their song, so that it must be pleasing to the ears of some men.  (23.
These particulars are taken from Westwood's 'Modern Classification of
Insects,' vol. ii. 1840, p. 422.  See, also, on the Fulgoridae, Kirby and
Spence, 'Introduct.' vol. ii. p. 401.)  The Cicadidae usually sing during
the day, whilst the Fulgoridae appear to be night-songsters.  The sound,
according to Landois (24.  'Zeitschrift fuer wissenschaft. Zoolog.' B. xvii.
1867, ss. 152-158.), is produced by the vibration of the lips of the
spiracles, which are set into motion by a current of air emitted from the
tracheae; but this view has lately been disputed.  Dr. Powell appears to
have proved (25.  'Transactions of the New Zealand Institute,' vol. v.
1873, p. 286.) that it is produced by the vibration of a membrane, set into
action by a special muscle.  In the living insect, whilst stridulating,
this membrane can be seen to vibrate; and in the dead insect the proper
sound is heard, if the muscle, when a little dried and hardened, is pulled
with the point of a pin.  In the female the whole complex musical apparatus
is present, but is much less developed than in the male, and is never used
for producing sound.

With respect to the object of the music,  Dr. Hartman, in speaking of the
Cicada septemdecim of the United States, says (26.  I am indebted to Mr.
Walsh for having sent me this extract from 'A Journal of the Doings of
Cicada septemdecim,' by Dr. Hartman.), "the drums are now (June 6th and
7th, 1851) heard in all directions.  This I believe to be the marital
summons from the males.  Standing in thick chestnut sprouts about as high
as my head, where hundreds were around me, I observed the females coming
around the drumming males."  He adds, "this season (Aug. 1868) a dwarf
pear-tree in my garden produced about fifty larvae of Cic. pruinosa; and I
several times noticed the females to alight near a male while he was
uttering his clanging notes."  Fritz Mueller writes to me from S. Brazil
that he has often listened to a musical contest between two or three males
of a species with a particularly loud voice, seated at a considerable
distance from each other:  as soon as one had finished his song, another
immediately began, and then another.  As there is so much rivalry between
the males, it is probable that the females not only find them by their
sounds, but that, like female birds, they are excited or allured by the
male with the most attractive voice.

I have not heard of any well-marked cases of ornamental differences between
the sexes of the Homoptera.  Mr. Douglas informs me that there are three
British species, in which the male is black or marked with black bands,
whilst the females are pale-coloured or obscure.

ORDER, ORTHOPTERA (CRICKETS AND GRASSHOPPERS).

The males in the three saltatorial families in this Order are remarkable
for their musical powers, namely the Achetidae or crickets, the Locustidae
for which there is no equivalent English name, and the Acridiidae or
grasshoppers.  The stridulation produced by some of the Locustidae is so
loud that it can be heard during the night at the distance of a mile (27.
L. Guilding, 'Transactions of the Linnean Society,' vol. xv. p. 154.); and
that made by certain species is not unmusical even to the human ear, so
that the Indians on the Amazons keep them in wicker cages.  All observers
agree that the sounds serve either to call or excite the mute females.
With respect to the migratory locusts of Russia, Korte has given (28.  I
state this on the authority of Koppen, 'Ueber die Heuschrecken in
Suedrussland,' 1866, p. 32, for I have in vain endeavoured to procure
Korte's work.) an interesting case of selection by the female of a male.
The males of this species (Pachytylus migratorius) whilst coupled with the
female stridulate from anger or jealousy, if approached by other males.
The house-cricket when surprised at night uses its voice to warn its
fellows.  (29.  Gilbert White, 'Natural History of Selborne,' vol. ii.
1825, p. 262.)  In North America the Katy-did (Platyphyllum concavum, one
of the Locustidae) is described (30.  Harris, 'Insects of New England,'
1842, p. 128.) as mounting on the upper branches of a tree, and in the
evening beginning "his noisy babble, while rival notes issue from the
neighbouring trees, and the groves resound with the call of Katy-did-she-
did the live-long night."  Mr. Bates, in speaking of the European field-
cricket (one of the Achetidae), says "the male has been observed to place
himself in the evening at the entrance of his burrow, and stridulate until
a female approaches, when the louder notes are succeeded by a more subdued
tone, whilst the successful musician caresses with his antennae the mate he
has won." (31.  'The Naturalist on the Amazons,' vol. i. 1863, p. 252.  Mr.
Bates gives a very interesting discussion on the gradations in the musical
apparatus of the three families.  See also Westwood, 'Modern Classification
of Insects,' vol. ii. pp. 445 and 453.)  Dr. Scudder was able to excite one
of these insects to answer him, by rubbing on a file with a quill.  (32.
'Proceedings of the Boston Society of Natural History,' vol. xi. April
1868.)  In both sexes a remarkable auditory apparatus has been discovered
by Von Siebold, situated in the front legs.  (33.  'Nouveau Manuel d'Anat.
Comp.'  (French translat.), tom. 1, 1850, p. 567.)

[Fig.11.  Gryllus campestris (from Landois).
Right-hand figure, under side of part of a wing-nervure, much magnified,
showing the teeth, st.
Left-hand figure, upper surface of wing-cover, with the projecting, smooth
nervure, r, across which the teeth (st) are scraped.

Fig.12.  Teeth of Nervure of Gryllus domesticus (from Landois).]

In the three Families the sounds are differently produced.  In the males of
the Achetidae both wing-covers have the same apparatus; and this in the
field-cricket (see Gryllus campestris, Fig. 11) consists, as described by
Landois (34.  'Zeitschrift fuer wissenschaft. Zoolog.' B. xvii. 1867, s.
117.), of from 131 to 138 sharp, transverse ridges or teeth (st) on the
under side of one of the nervures of the wing-cover.  This toothed nervure
is rapidly scraped across a projecting, smooth, hard nervure (r) on the
upper surface of the opposite wing.  First one wing is rubbed over the
other, and then the movement is reversed.  Both wings are raised a little
at the same time, so as to increase the resonance.  In some species the
wing-covers of the males are furnished at the base with a talc-like plate.
(35.  Westwood, 'Modern Classification of Insects,' vol. i. p. 440.)  I
here give a drawing (Fig. 12) of the teeth on the under side of the nervure
of another species of Gryllus, viz., G. domesticus.  With respect to the
formation of these teeth, Dr. Gruber has shewn (36.  'Ueber der Tonapparat
der Locustiden, ein Beitrag zum Darwinismus,' 'Zeitschrift fuer
wissenschaft. Zoolog.' B. xxii. 1872, p. 100.) that they have been
developed by the aid of selection, from the minute scales and hairs with
which the wings and body are covered, and I came to the same conclusion
with respect to those of the Coleoptera.  But Dr. Gruber further shews that
their development is in part directly due to the stimulus from the friction
of one wing over the other.

[Fig.13.  Chlorocoelus Tanana (from Bates).
a,b.  Lobes of opposite wing-covers.]

In the Locustidae the opposite wing-covers differ from each other in
structure (Fig. 13), and the action cannot, as in the last family, be
reversed.  The left wing, which acts as the bow, lies over the right wing
which serves as the fiddle.  One of the nervures (a) on the under surface
of the former is finely serrated, and is scraped across the prominent
nervures on the upper surface of the opposite or right wing.  In our
British Phasgonura viridissima it appeared to me that the serrated nervure
is rubbed against the rounded hind-corner of the opposite wing, the edge of
which is thickened, coloured brown, and very sharp.  In the right wing, but
not in the left, there is a little plate, as transparent as talc,
surrounded by nervures, and called the speculum.  In Ephippiger vitium, a
member of this same family, we have a curious subordinate modification; for
the wing-covers are greatly reduced in size, but "the posterior part of the
pro-thorax is elevated into a kind of dome over the wing-covers, and which
has probably the effect of increasing the sound."  (37.  Westwood 'Modern
Classification of Insects,' vol. i. p. 453.)

We thus see that the musical apparatus is more differentiated or
specialised in the Locustidae (which include, I believe, the most powerful
performers in the Order), than in the Achetidae, in which both wing-covers
have the same structure and the same function.  (38.  Landois, 'Zeitschrift
fuer wissenschaft. Zoolog.' B. xvii. 1867, ss. 121, 122.)  Landois, however,
detected in one of the Locustidae, namely in Decticus, a short and narrow
row of small teeth, mere rudiments, on the inferior surface of the right
wing-cover, which underlies the other and is never used as the bow.  I
observed the same rudimentary structure on the under side of the right
wing-cover in Phasgonura viridissima.  Hence we may infer with confidence
that the Locustidae are descended from a form, in which, as in the existing
Achetidae, both wing-covers had serrated nervures on the under surface, and
could be indifferently used as the bow; but that in the Locustidae the two
wing-covers gradually became differentiated and perfected, on the principle
of the division of labour, the one to act exclusively as the bow, and the
other as the fiddle.  Dr. Gruber takes the same view, and has shewn that
rudimentary teeth are commonly found on the inferior surface of the right
wing.  By what steps the more simple apparatus in the Achetidae originated,
we do not know, but it is probable that the basal portions of the wing-
covers originally overlapped each other as they do at present; and that the
friction of the nervures produced a grating sound, as is now the case with
the wing-covers of the females.  (39.  Mr. Walsh also informs me that he
has noticed that the female of the Platyphyllum concavum, "when captured
makes a feeble grating noise by shuffling her wing-covers together.")  A
grating sound thus occasionally and accidentally made by the males, if it
served them ever so little as a love-call to the females, might readily
have been intensified through sexual selection, by variations in the
roughness of the nervures having been continually preserved.

[Fig.14.  Hind-leg of Stenobothrus pratorum:
r, the stridulating ridge;
lower figure, the teeth forming the ridge, much magnified (from Landois).

Fig.15.  Pneumora (from specimens in the British Museum).
Upper figure, male;
lower figure, female.]

In the last and third family, namely the Acridiidae or grasshoppers, the
stridulation is produced in a very different manner, and according to Dr.
Scudder, is not so shrill as in the preceding Families.  The inner surface
of the femur (Fig. 14, r) is furnished with a longitudinal row of minute,
elegant, lancet-shaped, elastic teeth, from 85 to 93 in number (40.
Landois, ibid. s. 113.); and these are scraped across the sharp, projecting
nervures on the wing-covers, which are thus made to vibrate and resound.
Harris (41.  'Insects of New England,' 1842, p. 133.) says that when one of
the males begins to play, he first "bends the shank of the hind-leg beneath
the thigh, where it is lodged in a furrow designed to receive it, and then
draws the leg briskly up and down.  He does not play both fiddles together,
but alternately, first upon one and then on the other."  In many species,
the base of the abdomen is hollowed out into a great cavity which is
believed to act as a resounding board.  In Pneumora (Fig. 15), a S. African
genus belonging to the same family, we meet with a new and remarkable
modification; in the males a small notched ridge projects obliquely from
each side of the abdomen, against which the hind femora are rubbed.  (42.
Westwood, 'Modern Classification,' vol i. p. 462.)  As the male is
furnished with wings (the female being wingless), it is remarkable that the
thighs are not rubbed in the usual manner against the wing-covers; but this
may perhaps be accounted for by the unusually small size of the hind-legs.
I have not been able to examine the inner surface of the thighs, which,
judging from analogy, would be finely serrated.  The species of Pneumora
have been more profoundly modified for the sake of stridulation than any
other orthopterous insect; for in the male the whole body has been
converted into a musical instrument, being distended with air, like a great
pellucid bladder, so as to increase the resonance.  Mr. Trimen informs me
that at the Cape of Good Hope these insects make a wonderful noise during
the night.

In the three foregoing families, the females are almost always destitute of
an efficient musical apparatus.  But there are a few exceptions to this
rule, for Dr. Gruber has shewn that both sexes of Ephippiger vitium are
thus provided; though the organs differ in the male and female to a certain
extent.  Hence we cannot suppose that they have been transferred from the
male to the female, as appears to have been the case with the secondary
sexual characters of many other animals.  They must have been independently
developed in the two sexes, which no doubt mutually call to each other
during the season of love.  In most other Locustidae (but not according to
Landois in Decticus) the females have rudiments of the stridulatory organs
proper to the male; from whom it is probable that these have been
transferred.  Landois also found such rudiments on the under surface of the
wing-covers of the female Achetidae, and on the femora of the female
Acridiidae.  In the Homoptera, also, the females have the proper musical
apparatus in a functionless state; and we shall hereafter meet in other
divisions of the animal kingdom with many instances of structures proper to
the male being present in a rudimentary condition in the female.

Landois has observed another important fact, namely, that in the females of
the Acridiidae, the stridulating teeth on the femora remain throughout life
in the same condition in which they first appear during the larval state in
both sexes.  In the males, on the other hand, they become further
developed, and acquire their perfect structure at the last moult, when the
insect is mature and ready to breed.

From the facts now given, we see that the means by which the males of the
Orthoptera produce their sounds are extremely diversified, and are
altogether different from those employed by the Homoptera.  (43.  Landois
has recently found in certain Orthoptera rudimentary structures closely
similar to the sound-producing organs in the Homoptera; and this is a
surprising fact.  See 'Zeitschrift fuer wissenschaft, Zoolog.' B. xxii. Heft
3, 1871, p. 348.)  But throughout the animal kingdom we often find the same
object gained by the most diversified means; this seems due to the whole
organisation having undergone multifarious changes in the course of ages,
and as part after part varied different variations were taken advantage of
for the same general purpose.  The diversity of means for producing sound
in the three families of the Orthoptera and in the Homoptera, impresses the
mind with the high importance of these structures to the males, for the
sake of calling or alluring the females.  We need feel no surprise at the
amount of modification which the Orthoptera have undergone in this respect,
as we now know, from Dr. Scudder's remarkable discovery (44.
'Transactions, Entomological Society,' 3rd series, vol. ii. ('Journal of
Proceedings,' p. 117).), that there has been more than ample time.  This
naturalist has lately found a fossil insect in the Devonian formation of
New Brunswick, which is furnished with "the well-known tympanum or
stridulating apparatus of the male Locustidae."  The insect, though in most
respects related to the Neuroptera, appears, as is so often the case with
very ancient forms, to connect the two related Orders of the Neuroptera and
Orthoptera.

I have but little more to say on the Orthoptera.  Some of the species are
very pugnacious:  when two male field-crickets (Gryllus campestris) are
confined together, they fight till one kills the other; and the species of
Mantis are described as manoeuvring with their sword-like front-limbs, like
hussars with their sabres.  The Chinese keep these insects in little bamboo
cages, and match them like game-cocks.  (45.  Westwood, 'Modern
Classification of Insects,' vol. i. p. 427; for crickets, p. 445.)  With
respect to colour, some exotic locusts are beautifully ornamented; the
posterior wings being marked with red, blue, and black; but as throughout
the Order the sexes rarely differ much in colour, it is not probable that
they owe their bright tints to sexual selection.  Conspicuous colours may
be of use to these insects, by giving notice that they are unpalatable.
Thus it has been observed (46.  Mr. Ch. Horne, in 'Proceedings of the
Entomological Society,' May 3, 1869, p. xii.) that a bright-coloured Indian
locust was invariably rejected when offered to birds and lizards.  Some
cases, however, are known of sexual differences in colour in this Order.
The male of an American cricket (47.  The Oecanthus nivalis, Harris,
'Insects of New England,' 1842, p. 124.  The two sexes of OE. pellucidus of
Europe differ, as I hear from Victor Carus, in nearly the same manner.) is
described as being as white as ivory, whilst the female varies from almost
white to greenish-yellow or dusky.  Mr. Walsh informs me that the adult
male of Spectrum femoratum (one of the Phasmidae) "is of a shining
brownish-yellow colour; the adult female being of a dull, opaque, cinereous
brown; the young of both sexes being green."  Lastly, I may mention that
the male of one curious kind of cricket (48.  Platyblemnus:  Westwood,
'Modern Classification,' vol. i. p. 447.) is furnished with "a long
membranous appendage, which falls over the face like a veil;" but what its
use may be, is not known.

ORDER, NEUROPTERA.

Little need here be said, except as to colour.  In the Ephemeridae the
sexes often differ slightly in their obscure tints (49.  B.D. Walsh, the
'Pseudo-neuroptera of Illinois,' in 'Proceedings of the Entomological
Society of Philadelphia,' 1862, p. 361.); but it is not probable that the
males are thus rendered attractive to the females.  The Libellulidae, or
dragon-flies, are ornamented with splendid green, blue, yellow, and
vermilion metallic tints; and the sexes often differ.  Thus, as Prof.
Westwood remarks (50.  'Modern Classification,' vol. ii. p. 37.), the males
of some of the Agrionidae, "are of a rich blue with black wings, whilst the
females are fine green with colourless wings."  But in Agrion Ramburii
these colours are exactly reversed in the two sexes.  (51.  Walsh, ibid. p.
381.  I am indebted to this naturalist for the following facts on
Hetaerina, Anax, and Gomphus.)  In the extensive N. American genus of
Hetaerina, the males alone have a beautiful carmine spot at the base of
each wing.  In Anax junius the basal part of the abdomen in the male is a
vivid ultramarine blue, and in the female grass-green.  In the allied genus
Gomphus, on the other hand, and in some other genera, the sexes differ but
little in colour.  In closely-allied forms throughout the animal kingdom,
similar cases of the sexes differing greatly, or very little, or not at
all, are of frequent occurrence.  Although there is so wide a difference in
colour between the sexes of many Libellulidae, it is often difficult to say
which is the more brilliant; and the ordinary coloration of the two sexes
is reversed, as we have just seen, in one species of Agrion.  It is not
probable that their colours in any case have been gained as a protection.
Mr. MacLachlan, who has closely attended to this family, writes to me that
dragon-flies--the tyrants of the insect-world--are the least liable of any
insect to be attacked by birds or other enemies, and he believes that their
bright colours serve as a sexual attraction.  Certain dragon-flies
apparently are attracted by particular colours:  Mr. Patterson observed
(52.  'Transactions, Ent. Soc.' vol. i. 1836, p. lxxxi.) that the
Agrionidae, of which the males are blue, settled in numbers on the blue
float of a fishing line; whilst two other species were attracted by shining
white colours.

It is an interesting fact, first noticed by Schelver, that, in several
genera belonging to two sub-families, the males on first emergence from the
pupal state, are coloured exactly like the females; but that their bodies
in a short time assume a conspicuous milky-blue tint, owing to the
exudation of a kind of oil, soluble in ether and alcohol.  Mr. MacLachlan
believes that in the male of Libellula depressa this change of colour does
not occur until nearly a fortnight after the metamorphosis, when the sexes
are ready to pair.

Certain species of Neurothemis present, according to Brauer (53.  See
abstract in the 'Zoological Record' for 1867, p. 450.), a curious case of
dimorphism, some of the females having ordinary wings, whilst others have
them "very richly netted, as in the males of the same species."  Brauer
"explains the phenomenon on Darwinian principles by the supposition that
the close netting of the veins is a secondary sexual character in the
males, which has been abruptly transferred to some of the females, instead
of, as generally occurs, to all of them."  Mr. MacLachlan informs me of
another instance of dimorphism in several species of Agrion, in which some
individuals are of an orange colour, and these are invariably females.
This is probably a case of reversion; for in the true Libellulae, when the
sexes differ in colour, the females are orange or yellow; so that supposing
Agrion to be descended from some primordial form which resembled the
typical Libellulae in its sexual characters, it would not be surprising
that a tendency to vary in this manner should occur in the females alone.

Although many dragon-flies are large, powerful, and fierce insects, the
males have not been observed by Mr. MacLachlan to fight together,
excepting, as he believes, in some of the smaller species of Agrion.  In
another group in this Order, namely, the Termites or white ants, both sexes
at the time of swarming may be seen running about, "the male after the
female, sometimes two chasing one female, and contending with great
eagerness who shall win the prize."  (54.  Kirby and Spence, 'Introduction
to Entomology,' vol. ii. 1818, p. 35.)  The Atropos pulsatorius is said to
make a noise with its jaws, which is answered by other individuals.  (55.
Houzeau, 'Les Facultes Mentales,' etc. Tom. i. p. 104.)

ORDER, HYMENOPTERA.

That inimitable observer, M. Fabre (56.  See an interesting article, 'The
Writings of Fabre,' in 'Nat. Hist. Review,' April 1862, p. 122.), in
describing the habits of Cerceris, a wasp-like insect, remarks that "fights
frequently ensue between the males for the possession of some particular
female, who sits an apparently unconcerned beholder of the struggle for
supremacy, and when the victory is decided, quietly flies away in company
with the conqueror."  Westwood (57.  'Journal of Proceedings of
Entomological Society,' Sept. 7, 1863, p. 169.) says that the males of one
of the saw-flies (Tenthredinae) "have been found fighting together, with
their mandibles locked."  As M. Fabre speaks of the males of Cerceris
striving to obtain a particular female, it may be well to bear in mind that
insects belonging to this Order have the power of recognising each other
after long intervals of time, and are deeply attached.  For instance,
Pierre Huber, whose accuracy no one doubts, separated some ants, and when,
after an interval of four months, they met others which had formerly
belonged to the same community, they recognised and caressed one another
with their antennae.  Had they been strangers they would have fought
together.  Again, when two communities engage in a battle, the ants on the
same side sometimes attack each other in the general confusion, but they
soon perceive their mistake, and the one ant soothes the other.  (58.  P.
Huber, 'Recherches sur les Moeurs des Fourmis,' 1810, pp. 150, 165.)

In this Order slight differences in colour, according to sex, are common,
but conspicuous differences are rare except in the family of Bees; yet both
sexes of certain groups are so brilliantly coloured--for instance in
Chrysis, in which vermilion and metallic greens prevail--that we are
tempted to attribute the result to sexual selection.  In the Ichneumonidae,
according to Mr. Walsh (59.  'Proceedings of the Entomological Society of
Philadelphia,' 1866, pp. 238, 239.), the males are almost universally
lighter-coloured than the females.  On the other hand, in the
Tenthredinidae the males are generally darker than the females.  In the
Siricidae the sexes frequently differ; thus the male of Sirex juvencus is
banded with orange, whilst the female is dark purple; but it is difficult
to say which sex is the more ornamented.  In Tremex columbae the female is
much brighter coloured than the male.  I am informed by Mr. F. Smith, that
the male ants of several species are black, the females being testaceous.

In the family of Bees, especially in the solitary species, as I hear from
the same entomologist, the sexes often differ in colour.  The males are
generally the brighter, and in Bombus as well as in Apathus, much more
variable in colour than the females.  In Anthophora retusa the male is of a
rich fulvous-brown, whilst the female is quite black:  so are the females
of several species of Xylocopa, the males being bright yellow.  On the
other hand the females of some species, as of Andraena fulva, are much
brighter coloured than the males.  Such differences in colour can hardly be
accounted for by the males being defenceless and thus requiring protection,
whilst the females are well defended by their stings.  H. Mueller (60.
'Anwendung der Darwinschen Lehre auf Bienen,' Verh. d. n. V. Jahrg. xxix.),
who has particularly attended to the habits of bees, attributes these
differences in colour in chief part to sexual selection.  That bees have a
keen perception of colour is certain.  He says that the males search
eagerly and fight for the possession of the females; and he accounts
through such contests for the mandibles of the males being in certain
species larger than those of the females.  In some cases the males are far
more numerous than the females, either early in the season, or at all times
and places, or locally; whereas the females in other cases are apparently
in excess.  In some species the more beautiful males appear to have been
selected by the females; and in others the more beautiful females by the
males.  Consequently in certain genera (Mueller, p. 42), the males of the
several species differ much in appearance, whilst the females are almost
indistinguishable; in other genera the reverse occurs.  H. Mueller believes
(p. 82) that the colours gained by one sex through sexual selection have
often been transferred in a variable degree to the other sex, just as the
pollen-collecting apparatus of the female has often been transferred to the
male, to whom it is absolutely useless.  (61.  M. Perrier in his article
'la Selection sexuelle d'apres Darwin' ('Revue Scientifique,' Feb. 1873, p.
868), without apparently having reflected much on the subject, objects that
as the males of social bees are known to be produced from unfertilised ova,
they could not transmit new characters to their male offspring.  This is an
extraordinary objection.  A female bee fertilised by a male, which
presented some character facilitating the union of the sexes, or rendering
him more attractive to the female, would lay eggs which would produce only
females; but these young females would next year produce males; and will it
be pretended that such males would not inherit the characters of their male
grandfathers?  To take a case with ordinary animals as nearly parallel as
possible:  if a female of any white quadruped or bird were crossed by a
male of a black breed, and the male and female offspring were paired
together, will it be pretended that the grandchildren would not inherit a
tendency to blackness from their male grandfather?  The acquirement of new
characters by the sterile worker-bees is a much more difficult case, but I
have endeavoured to shew in my 'Origin of Species,' how these sterile
beings are subjected to the power of natural selection.)

Mutilla Europaea makes a stridulating noise; and according to Goureau (62.
Quoted by Westwood, 'Modern Classification of Insects,' vol. ii. p. 214.)
both sexes have this power.  He attributes the sound to the friction of the
third and preceding abdominal segments, and I find that these surfaces are
marked with very fine concentric ridges; but so is the projecting thoracic
collar into which the head articulates, and this collar, when scratched
with the point of a needle, emits the proper sound.  It is rather
surprising that both sexes should have the power of stridulating, as the
male is winged and the female wingless.  It is notorious that Bees express
certain emotions, as of anger, by the tone of their humming; and according
to H. Mueller (p. 80), the males of some species make a peculiar singing
noise whilst pursuing the females.

ORDER, COLEOPTERA (BEETLES).

Many beetles are coloured so as to resemble the surfaces which they
habitually frequent, and they thus escape detection by their enemies.
Other species, for instance diamond-beetles, are ornamented with splendid
colours, which are often arranged in stripes, spots, crosses, and other
elegant patterns.  Such colours can hardly serve directly as a protection,
except in the case of certain flower-feeding species; but they may serve as
a warning or means of recognition, on the same principle as the
phosphorescence of the glow-worm.  As with beetles the colours of the two
sexes are generally alike, we have no evidence that they have been gained
through sexual selection; but this is at least possible, for they have been
developed in one sex and then transferred to the other; and this view is
even in some degree probable in those groups which possess other well-
marked secondary sexual characters.  Blind beetles, which cannot of course
behold each other's beauty, never, as I hear from Mr. Waterhouse, jun.,
exhibit bright colours, though they often have polished coats; but the
explanation of their obscurity may be that they generally inhabit caves and
other obscure stations.

Some Longicorns, especially certain Prionidae, offer an exception to the
rule that the sexes of beetles do not differ in colour.  Most of these
insects are large and splendidly coloured.  The males in the genus Pyrodes
(63.  Pyrodes pulcherrimus, in which the sexes differ conspicuously, has
been described by Mr. Bates in 'Transact. Ent. Soc.' 1869, p. 50.  I will
specify the few other cases in which I have heard of a difference in colour
between the sexes of beetles.  Kirby and Spence ('Introduct. to
Entomology,' vol. iii. p. 301) mention a Cantharis, Meloe, Rhagium, and the
Leptura testacea; the male of the latter being testaceous, with a black
thorax, and the female of a dull red all over.  These two latter beetles
belong to the family of Longicorns.  Messrs. R. Trimen and Waterhouse,
jun., inform me of two Lamellicorns, viz., a Peritrichia and Trichius, the
male of the latter being more obscurely coloured than the female.  In
Tillus elongatus the male is black, and the female always, as it is
believed, of a dark blue colour, with a red thorax.  The male, also, of
Orsodacna atra, as I hear from Mr. Walsh, is black, the female (the so-
called O. ruficollis) having a rufous thorax.), which I saw in Mr. Bates's
collection, are generally redder but rather duller than the females, the
latter being coloured of a more or less splendid golden-green.  On the
other hand, in one species the male is golden-green, the female being
richly tinted with red and purple.  In the genus Esmeralda the sexes differ
so greatly in colour that they have been ranked as distinct species; in one
species both are of a beautiful shining green, but the male has a red
thorax.  On the whole, as far as I could judge, the females of those
Prionidae, in which the sexes differ, are coloured more richly than the
males, and this does not accord with the common rule in regard to colour,
when acquired through sexual selection.

[Fig.16.  Chalcosoma atlas.
Upper figure, male (reduced);
lower figure, female (nat. size).

Fig. 17.  Copris isidis.

Fig. 18.  Phanaeus faunus.

Fig. 19.  Dipelicus cantori.

Fig. 20.  Onthophagus rangifer, enlarged.
(In Figs. 17 to 20 the left-hand figures are males.)]

A most remarkable distinction between the sexes of many beetles is
presented by the great horns which rise from the head, thorax, and clypeus
of the males; and in some few cases from the under surface of the body.
These horns, in the great family of the Lamellicorns, resemble those of
various quadrupeds, such as stags, rhinoceroses, etc., and are wonderful
both from their size and diversified shapes.  Instead of describing them, I
have given figures of the males and females of some of the more remarkable
forms.  (Figs. 16 to 20.)  The females generally exhibit rudiments of the
horns in the form of small knobs or ridges; but some are destitute of even
the slightest rudiment.  On the other hand, the horns are nearly as well
developed in the female as in the male Phanaeus lancifer; and only a little
less well developed in the females of some other species of this genus and
of Copris.  I am informed by Mr. Bates that the horns do not differ in any
manner corresponding with the more important characteristic differences
between the several subdivisions of the family:  thus within the same
section of the genus Onthophagus, there are species which have a single
horn, and others which have two.

In almost all cases, the horns are remarkable from their excessive
variability; so that a graduated series can be formed, from the most highly
developed males to others so degenerate that they can barely be
distinguished from the females.  Mr. Walsh (64.  'Proceedings of the
Entomological Society of Philadephia,' 1864, p. 228.) found that in
Phanaeus carnifex the horns were thrice as long in some males as in others.
Mr. Bates, after examining above a hundred males of Onthophagus rangifer
(Fig. 20), thought that he had at last discovered a species in which the
horns did not vary; but further research proved the contrary.

The extraordinary size of the horns, and their widely different structure
in closely-allied forms, indicate that they have been formed for some
purpose; but their excessive variability in the males of the same species
leads to the inference that this purpose cannot be of a definite nature.
The horns do not shew marks of friction, as if used for any ordinary work.
Some authors suppose (65.  Kirby and Spence, 'Introduction to Entomology,'
vol. iii. p. 300.) that as the males wander about much more than the
females, they require horns as a defence against their enemies; but as the
horns are often blunt, they do not seem well adapted for defence.  The most
obvious conjecture is that they are used by the males for fighting
together; but the males have never been observed to fight; nor could Mr.
Bates, after a careful examination of numerous species, find any sufficient
evidence, in their mutilated or broken condition, of their having been thus
used.  If the males had been habitual fighters, the size of their bodies
would probably have been increased through sexual selection, so as to have
exceeded that of the females; but Mr. Bates, after comparing the two sexes
in above a hundred species of the Copridae, did not find any marked
difference in this respect amongst well-developed individuals.  In Lethrus,
moreover, a beetle belonging to the same great division of the
Lamellicorns, the males are known to fight, but are not provided with
horns, though their mandibles are much larger than those of the female.

The conclusion that the horns have been acquired as ornaments is that which
best agrees with the fact of their having been so immensely, yet not
fixedly, developed,--as shewn by their extreme variability in the same
species, and by their extreme diversity in closely-allied species.  This
view will at first appear extremely improbable; but we shall hereafter find
with many animals standing much higher in the scale, namely fishes,
amphibians, reptiles and birds, that various kinds of crests, knobs, horns
and combs have been developed apparently for this sole purpose.

[Fig.21.  Onitis furcifer, male viewed from beneath.

Fig.22.  Onitis furcifer.
Left-hand figure, male, viewed laterally.
Right-hand figure, female.
a. Rudiment of cephalic horn.
b. Trace of thoracic horn or crest.]

The males of Onitis furcifer (Fig. 21), and of some other species of the
genus, are furnished with singular projections on their anterior femora,
and with a great fork or pair of horns on the lower surface of the thorax.
Judging from other insects, these may aid the male in clinging to the
female.  Although the males have not even a trace of a horn on the upper
surface of the body, yet the females plainly exhibit a rudiment of a single
horn on the head (Fig. 22, a), and of a crest (b) on the thorax.  That the
slight thoracic crest in the female is a rudiment of a projection proper to
the male, though entirely absent in the male of this particular species, is
clear:  for the female of Bubas bison (a genus which comes next to Onitis)
has a similar slight crest on the thorax, and the male bears a great
projection in the same situation.  So, again, there can hardly be a doubt
that the little point (a) on the head of the female Onitis furcifer, as
well as on the head of the females of two or three allied species, is a
rudimentary representative of the cephalic horn, which is common to the
males of so many Lamellicorn beetles, as in Phanaeus (Fig. 18).

The old belief that rudiments have been created to complete the scheme of
nature is here so far from holding good, that we have a complete inversion
of the ordinary state of things in the family.  We may reasonably suspect
that the males originally bore horns and transferred them to the females in
a rudimentary condition, as in so many other Lamellicorns.  Why the males
subsequently lost their horns, we know not; but this may have been caused
through the principle of compensation, owing to the development of the
large horns and projections on the lower surface; and as these are confined
to the males, the rudiments of the upper horns on the females would not
have been thus obliterated.

[Fig. 23.  Bledius taurus, magnified.
Left-hand figure, male;
right-hand figure, female.]

The cases hitherto given refer to the Lamellicorns, but the males of some
few other beetles, belonging to two widely distinct groups, namely, the
Curculionidae and Staphylinidae, are furnished with horns--in the former on
the lower surface of the body (66.  Kirby and Spence, 'Introduction to
Entomology,' vol. iii. p. 329.), in the latter on the upper surface of the
head and thorax.  In the Staphylinidae, the horns of the males are
extraordinarily variable in the same species, just as we have seen with the
Lamellicorns.  In Siagonium we have a case of dimorphism, for the males can
be divided into two sets, differing greatly in the size of their bodies and
in the development of their horns, without intermediate gradations.  In a
species of Bledius (Fig. 23), also belonging to the Staphylinidae,
Professor Westwood states that, "male specimens can be found in the same
locality in which the central horn of the thorax is very large, but the
horns of the head quite rudimental; and others, in which the thoracic horn
is much shorter, whilst the protuberances on the head are long."  (67.
'Modern Classification of Insects,' vol. i. p. 172:  Siagonium, p. 172.  In
the British Museum I noticed one male specimen of Siagonium in an
intermediate condition, so that the dimorphism is not strict.)  Here we
apparently have a case of compensation, which throws light on that just
given, of the supposed loss of the upper horns by the males of Onitis.

LAW OF BATTLE.

Some male beetles, which seem ill-fitted for fighting, nevertheless engage
in conflicts for the possession of the females.  Mr. Wallace (68.  'The
Malay Archipelago,' vol. ii. 1869, p. 276.  Riley, Sixth 'Report on Insects
of Missouri,' 1874, p. 115.) saw two males of Leptorhynchus angustatus, a
linear beetle with a much elongated rostrum, "fighting for a female, who
stood close by busy at her boring.  They pushed at each other with their
rostra, and clawed and thumped, apparently in the greatest rage."  The
smaller male, however, "soon ran away, acknowledging himself vanquished."
In some few cases male beetles are well adapted for fighting, by possessing
great toothed mandibles, much larger than those of the females.  This is
the case with the common stag-beetle (Lucanus cervus), the males of which
emerge from the pupal state about a week before the other sex, so that
several may often be seen pursuing the same female.  At this season they
engage in fierce conflicts.  When Mr. A.H. Davis (69.  'Entomological
Magazine,' vol. i. 1833, p. 82.  See also on the conflicts of this species,
Kirby and Spence, ibid. vol. iii. p. 314; and Westwood, ibid. vol. i. p.
187.) enclosed two males with one female in a box, the larger male severely
pinched the smaller one, until he resigned his pretensions.  A friend
informs me that when a boy he often put the males together to see them
fight, and he noticed that they were much bolder and fiercer than the
females, as with the higher animals.  The males would seize hold of his
finger, if held in front of them, but not so the females, although they
have stronger jaws.  The males of many of the Lucanidae, as well as of the
above-mentioned Leptorhynchus, are larger and more powerful insects than
the females.  The two sexes of Lethrus cephalotes (one of the Lamellicorns)
inhabit the same burrow; and the male has larger mandibles than the female.
If, during the breeding-season, a strange male attempts to enter the
burrow, he is attacked; the female does not remain passive, but closes the
mouth of the burrow, and encourages her mate by continually pushing him on
from behind; and the battle lasts until the aggressor is killed or runs
away.  (70.  Quoted from Fischer, in 'Dict. Class. d'Hist. Nat.' tom. x. p.
324.)  The two sexes of another Lamellicorn beetle, the Ateuchus
cicatricosus, live in pairs, and seem much attached to each other; the male
excites the females to roll the balls of dung in which the ova are
deposited; and if she is removed, he becomes much agitated.  If the male is
removed the female ceases all work, and as M. Brulerie believes, would
remain on the same spot until she died.  (71.  'Ann. Soc. Entomolog.
France,' 1866, as quoted in 'Journal of Travel,' by A. Murray, 1868, p.
135.)

[Fig. 24.  Chiasognathus Grantii, reduced.
Upper figure, male;
lower figure, female.]

The great mandibles of the male Lucanidae are extremely variable both in
size and structure, and in this respect resemble the horns on the head and
thorax of many male Lamellicorns and Staphylinidae.  A perfect series can
be formed from the best-provided to the worst-provided or degenerate males.
Although the mandibles of the common stag-beetle, and probably of many
other species, are used as efficient weapons for fighting, it is doubtful
whether their great size can thus be accounted for.  We have seen that they
are used by the Lucanus elaphus of N. America for seizing the female.  As
they are so conspicuous and so elegantly branched, and as owing to their
great length they are not well adapted for pinching, the suspicion has
crossed my mind that they may in addition serve as an ornament, like the
horns on the head and thorax of the various species above described.  The
male Chiasognathus grantii of S. Chile--a splendid beetle belonging to the
same family--has enormously developed mandibles (Fig. 24); he is bold and
pugnacious; when threatened he faces round, opens his great jaws, and at
the same time stridulates loudly.  But the mandibles were not strong enough
to pinch my finger so as to cause actual pain.

Sexual selection, which implies the possession of considerable perceptive
powers and of strong passions, seems to have been more effective with the
Lamellicorns than with any other family of beetles.  With some species the
males are provided with weapons for fighting; some live in pairs and shew
mutual affection; many have the power of stridulating when excited; many
are furnished with the most extraordinary horns, apparently for the sake of
ornament; and some, which are diurnal in their habits, are gorgeously
coloured.  Lastly, several of the largest beetles in the world belong to
this family, which was placed by Linnaeus and Fabricius as the head of the
Order.  (72.  Westwood, 'Modern Classification,' vol. i. p. 184.)

STRIDULATING ORGANS.

Beetles belonging to many and widely distinct families possess these
organs.  The sound thus produced can sometimes be heard at the distance of
several feet or even yards (73.  Wollaston, 'On Certain Musical
Curculionidae,' 'Annals and Mag. of Nat. Hist.' vol. vi. 1860, p. 14.), but
it is not comparable with that made by the Orthoptera.  The rasp generally
consists of a narrow, slightly-raised surface, crossed by very fine,
parallel ribs, sometimes so fine as to cause iridescent colours, and having
a very elegant appearance under the microscope.  In some cases, as with
Typhoeus, minute, bristly or scale-like prominences, with which the whole
surrounding surface is covered in approximately parallel lines, could be
traced passing into the ribs of the rasp.  The transition takes place by
their becoming confluent and straight, and at the same time more prominent
and smooth.  A hard ridge on an adjoining part of the body serves as the
scraper for the rasp, but this scraper in some cases has been specially
modified for the purpose.  It is rapidly moved across the rasp, or
conversely the rasp across the scraper.

[Fig.25.  Necrophorus (from Landois).
r. The two rasps.
Left-hand figure, part of the rasp highly magnified.]

These organs are situated in widely different positions.  In the carrion-
beetles (Necrophorus) two parallel rasps (r, Fig. 25) stand on the dorsal
surface of the fifth abdominal segment, each rasp (74.  Landois,
'Zeitschrift fur wissenschaft Zoolog.' B. xvii. 1867, s. 127.) consisting
of 126 to 140 fine ribs.  These ribs are scraped against the posterior
margins of the elytra, a small portion of which projects beyond the general
outline.  In many Crioceridae, and in Clythra 4-punctata (one of the
Chrysomelidae), and in some Tenebrionidae, etc. (75.  I am greatly indebted
to Mr. G.R. Crotch for having sent me many prepared specimens of various
beetles belonging to these three families and to others, as well as for
valuable information.  He believes that the power of stridulation in the
Clythra has not been previously observed.  I am also much indebted to Mr.
E.W. Janson, for information and specimens.  I may add that my son, Mr. F.
Darwin, finds that Dermestes murinus stridulates, but he searched in vain
for the apparatus.  Scolytus has lately been described by Dr. Chapman as a
stridulator, in the 'Entomologist's Monthly Magazine,' vol. vi. p. 130.),
the rasp is seated on the dorsal apex of the abdomen, on the pygidium or
pro-pygidium, and is scraped in the same manner by the elytra.  In
Heterocerus, which belongs to another family, the rasps are placed on the
sides of the first abdominal segment, and are scraped by ridges on the
femora.  (76.  Schiodte, translated, in 'Annals and Magazine of Natural
History,' vol. xx. 1867, p. 37.)  In certain Curculionidae and Carabidae
(77.  Westring has described (Kroyer, 'Naturhist. Tidskrift,' B. ii. 1848-
49, p. 334) the stridulating organs in these two, as well as in other
families.  In the Carabidae I have examined Elaphrus uliginosus and
Blethisa multipunctata, sent to me by Mr. Crotch.  In Blethisa the
transverse ridges on the furrowed border of the abdominal segment do not,
as far as I could judge, come into play in scraping the rasps on the
elytra.), the parts are completely reversed in position, for the rasps are
seated on the inferior surface of the elytra, near their apices, or along
their outer margins, and the edges of the abdominal segments serve as the
scrapers.  In Pelobius Hermanni (one of Dytiscidae or water-beetles) a
strong ridge runs parallel and near to the sutural margin of the elytra,
and is crossed by ribs, coarse in the middle part, but becoming gradually
finer at both ends, especially at the upper end; when this insect is held
under water or in the air, a stridulating noise is produced by the extreme
horny margin of the abdomen being scraped against the rasps.  In a great
number of long-horned beetles (Longicornia) the organs are situated quite
otherwise, the rasp being on the meso-thorax, which is rubbed against the
pro-thorax; Landois counted 238 very fine ribs on the rasp of Cerambyx
heros.

[Fig.26.  Hind-leg of Geotrupes stercorarius (from Landois).
r.  Rasp.  c. Coxa.  f. Femur.  t. Tibia.  tr. Tarsi.]

Many Lamellicorns have the power of stridulating, and the organs differ
greatly in position.  Some species stridulate very loudly, so that when Mr.
F. Smith caught a Trox sabulosus, a gamekeeper, who stood by, thought he
had caught a mouse; but I failed to discover the proper organs in this
beetle.  In Geotrupes and Typhoeus, a narrow ridge runs obliquely across
(r, Fig. 26) the coxa of each hind-leg (having in G. stercorarius 84 ribs),
which is scraped by a specially projecting part of one of the abdominal
segments.  In the nearly allied Copris lunaris, an excessively narrow fine
rasp runs along the sutural margin of the elytra, with another short rasp
near the basal outer margin; but in some other Coprini the rasp is seated,
according to Leconte (78.  I am indebted to Mr. Walsh, of Illinois, for
having sent me extracts from Leconte's 'Introduction to Entomology,' pp.
101, 143.), on the dorsal surface of the abdomen.  In Oryctes it is seated
on the pro-pygidium; and, according to the same entomologist, in some other
Dynastini, on the under surface of the elytra.  Lastly, Westring states
that in Omaloplia brunnea the rasp is placed on the pro-sternum, and the
scraper on the meta-sternum, the parts thus occupying the under surface of
the body, instead of the upper surface as in the Longicorns.

We thus see that in the different coleopterous families the stridulating
organs are wonderfully diversified in position, but not much in structure.
Within the same family some species are provided with these organs, and
others are destitute of them.  This diversity is intelligible, if we
suppose that originally various beetles made a shuffling or hissing noise
by the rubbing together of any hard and rough parts of their bodies, which
happened to be in contact; and that from the noise thus produced being in
some way useful, the rough surfaces were gradually developed into regular
stridulating organs.  Some beetles as they move, now produce, either
intentionally or unintentionally, a shuffling noise, without possessing any
proper organs for the purpose.  Mr. Wallace informs me that the Euchirus
longimanus (a Lamellicorn, with the anterior legs wonderfully elongated in
the male) "makes, whilst moving, a low hissing sound by the protrusion and
contraction of the abdomen; and when seized it produces a grating sound by
rubbing its hind-legs against the edges of the elytra."  The hissing sound
is clearly due to a narrow rasp running along the sutural margin of each
elytron; and I could likewise make the grating sound by rubbing the
shagreened surface of the femur against the granulated margin of the
corresponding elytron; but I could not here detect any proper rasp; nor is
it likely that I could have overlooked it in so large an insect.  After
examining Cychrus, and reading what Westring has written about this beetle,
it seems very doubtful whether it possesses any true rasp, though it has
the power of emitting a sound.

From the analogy of the Orthoptera and Homoptera, I expected to find the
stridulating organs in the Coleoptera differing according to sex; but
Landois, who has carefully examined several species, observed no such
difference; nor did Westring; nor did Mr. G.R. Crotch in preparing the many
specimens which he had the kindness to send me.  Any difference in these
organs, if slight, would, however, be difficult to detect, on account of
their great variability.  Thus, in the first pair of specimens of
Necrophorus humator and of Pelobius which I examined, the rasp was
considerably larger in the male than in the female; but not so with
succeeding specimens.  In Geotrupes stercorarius the rasp appeared to me
thicker, opaquer, and more prominent in three males than in the same number
of females; in order, therefore, to discover whether the sexes differed in
their power of stridulating, my son, Mr. F. Darwin, collected fifty-seven
living specimens, which he separated into two lots, according as they made
a greater or lesser noise, when held in the same manner.  He then examined
all these specimens, and found that the males were very nearly in the same
proportion to the females in both the lots.  Mr. F. Smith has kept alive
numerous specimens of Monoynchus pseudacori (Curculionidae), and is
convinced that both sexes stridulate, and apparently in an equal degree.

Nevertheless, the power of stridulating is certainly a sexual character in
some few Coleoptera.  Mr. Crotch discovered that the males alone of two
species of Heliopathes (Tenebrionidae) possess stridulating organs.  I
examined five males of H. gibbus, and in all these there was a well-
developed rasp, partially divided into two, on the dorsal surface of the
terminal abdominal segment; whilst in the same number of females there was
not even a rudiment of the rasp, the membrane of this segment being
transparent, and much thinner than in the male.  In H. cribratostriatus the
male has a similar rasp, excepting that it is not partially divided into
two portions, and the female is completely destitute of this organ; the
male in addition has on the apical margins of the elytra, on each side of
the suture, three or four short longitudinal ridges, which are crossed by
extremely fine ribs, parallel to and resembling those on the abdominal
rasp; whether these ridges serve as an independent rasp, or as a scraper
for the abdominal rasp, I could not decide:  the female exhibits no trace

of this latter structure.

Again, in three species of the Lamellicorn genus Oryctes, we have a nearly
parallel case.  In the females of O. gryphus and nasicornis the ribs on the
rasp of the pro-pygidium are less continuous and less distinct than in the
males; but the chief difference is that the whole upper surface of this
segment, when held in the proper light, is seen to be clothed with hairs,
which are absent or are represented by excessively fine down in the males.
It should be noticed that in all Coleoptera the effective part of the rasp
is destitute of hairs.  In O. senegalensis the difference between the sexes
is more strongly marked, and this is best seen when the proper abdominal
segment is cleaned and viewed as a transparent object.  In the female the
whole surface is covered with little separate crests, bearing spines;
whilst in the male these crests in proceeding towards the apex, become more
and more confluent, regular, and naked; so that three-fourths of the
segment is covered with extremely fine parallel ribs, which are quite
absent in the female.  In the females, however, of all three species of
Oryctes, a slight grating or stridulating sound is produced, when the
abdomen of a softened specimen is pushed backwards and forwards.

In the case of the Heliopathes and Oryctes there can hardly be a doubt that
the males stridulate in order to call or to excite the females; but with
most beetles the stridulation apparently serves both sexes as a mutual
call.  Beetles stridulate under various emotions, in the same manner as
birds use their voices for many purposes besides singing to their mates.
The great Chiasognathus stridulates in anger or defiance; many species do
the same from distress or fear, if held so that they cannot escape; by
striking the hollow stems of trees in the Canary Islands, Messrs. Wollaston
and Crotch were able to discover the presence of beetles belonging to the
genus Acalles by their stridulation.  Lastly, the male Ateuchus stridulates
to encourage the female in her work, and from distress when she is removed.
(79.  M. P. de la Brulerie, as quoted in 'Journal of Travel,' A. Murray,
vol. i. 1868, p. 135.)  Some naturalists believe that beetles make this
noise to frighten away their enemies; but I cannot think that a quadruped
or bird, able to devour a large beetle, would be frightened by so slight a
sound.  The belief that the stridulation serves as a sexual call is
supported by the fact that death-ticks (Anobium tessellatum) are well known
to answer each other's ticking, and, as I have myself observed, a tapping
noise artificially made.  Mr. Doubleday also informs me that he has
sometimes observed a female ticking (80.  According to Mr. Doubleday, "the
noise is produced by the insect raising itself on its legs as high as it
can, and then striking its thorax five or six times, in rapid succession,
against the substance upon which it is sitting."  For references on this
subject see Landois, 'Zeitschrift fuer wissen. Zoolog.' B. xvii. s. 131.
Olivier says (as quoted by Kirby and Spence, 'Introduction to Entomology,'
vol. ii. p. 395) that the female of Pimelia striata produces a rather loud
sound by striking her abdomen against any hard substance, "and that the
male, obedient to this call, soon attends her, and they pair."), and in an
hour or two afterwards has found her united with a male, and on one
occasion surrounded by several males.  Finally, it is probable that the two
sexes of many kinds of beetles were at first enabled to find each other by
the slight shuffling noise produced by the rubbing together of the
adjoining hard parts of their bodies; and that as those males or females
which made the greatest noise succeeded best in finding partners,
rugosities on various parts of their bodies were gradually developed by
means of sexual selection into true stridulating organs.


CHAPTER XI.

INSECTS, continued.

ORDER LEPIDOPTERA.  (BUTTERFLIES AND MOTHS.)

Courtship of butterflies--Battles--Ticking noise--Colours common to both

sexes, or more brilliant in the males--Examples--Not due to the direct
action of the conditions of life--Colours adapted for protection--Colours
of moths--Display--Perceptive powers of the Lepidoptera--Variability--
Causes of the difference in colour between the males and females--Mimicry,
female butterflies more brilliantly coloured than the males--Bright colours
of caterpillars--Summary and concluding remarks on the secondary sexual
characters of insects--Birds and insects compared.

In this great Order the most interesting points for us are the differences
in colour between the sexes of the same species, and between the distinct
species of the same genus.  Nearly the whole of the following chapter will
be devoted to this subject; but I will first make a few remarks on one or
two other points.  Several males may often be seen pursuing and crowding
round the same female.  Their courtship appears to be a prolonged affair,
for I have frequently watched one or more males pirouetting round a female
until I was tired, without seeing the end of the courtship.  Mr. A.G.
Butler also informs me that he has several times watched a male courting a
female for a full quarter of an hour; but she pertinaciously refused him,
and at last settled on the ground and closed her wings, so as to escape
from his addresses.

Although butterflies are weak and fragile creatures, they are pugnacious,
and an emperor butterfly (1.  Apatura Iris:  'The Entomologist's Weekly
Intelligence,' 1859, p. 139.  For the Bornean Butterflies, see C.
Collingwood, 'Rambles of a Naturalist,' 1868, p. 183.) has been captured
with the tips of its wings broken from a conflict with another male.  Mr.
Collingwood, in speaking of the frequent battles between the butterflies of
Borneo, says, "They whirl round each other with the greatest rapidity, and
appear to be incited by the greatest ferocity."

The Ageronia feronia makes a noise like that produced by a toothed wheel
passing under a spring catch, and which can be heard at the distance of
several yards:  I noticed this sound at Rio de Janeiro, only when two of
these butterflies were chasing each other in an irregular course, so that
it is probably made during the courtship of the sexes.  (2.  See my
'Journal of Researches,' 1845, p. 33.  Mr. Doubleday has detected ('Proc.
Ent. Soc.' March 3, 1845, p. 123) a peculiar membranous sac at the base of
the front wings, which is probably connected with the production of the
sound.  For the case of Thecophora, see 'Zoological Record,' 1869, p. 401.
For Mr. Buchanan White's observations, the Scottish Naturalist, July 1872,
p. 214.)

Some moths also produce sounds; for instance, the males Theocophora fovea.
On two occasions Mr. F. Buchanan White (3.  'The Scottish Naturalist,' July
1872, p. 213.) heard a sharp quick noise made by the male of Hylophila
prasinana, and which he believes to be produced, as in Cicada, by an
elastic membrane, furnished with a muscle.  He quotes, also, Guenee, that
Setina produces a sound like the ticking of a watch, apparently by the aid
of "two large tympaniform vesicles, situated in the pectoral region"; and
these "are much more developed in the male than in the female."  Hence the
sound-producing organs in the Lepidoptera appear to stand in some relation
with the sexual functions.  I have not alluded to the well-known noise made
by the Death's Head Sphinx, for it is generally heard soon after the moth
has emerged from its cocoon.

Giard has always observed that the musky odour, which is emitted by two
species of Sphinx moths, is peculiar to the males (4.  'Zoological Record,'
1869, p. 347.); and in the higher classes we shall meet with many instances
of the males alone being odoriferous.

Every one must have admired the extreme beauty of many butterflies and of
some moths; and it may be asked, are their colours and diversified patterns
the result of the direct action of the physical conditions to which these
insects have been exposed, without any benefit being thus derived?  Or have
successive variations been accumulated and determined as a protection, or
for some unknown purpose, or that one sex may be attractive to the other?
And, again, what is the meaning of the colours being widely different in
the males and females of certain species, and alike in the two sexes of
other species of the same genus?  Before attempting to answer these
questions a body of facts must be given.

With our beautiful English butterflies, the admiral, peacock, and painted
lady (Vanessae), as well as many others, the sexes are alike.  This is also
the case with the magnificent Heliconidae, and most of the Danaidae in the
tropics.  But in certain other tropical groups, and in some of our English
butterflies, as the purple emperor, orange-tip, etc. (Apatura Iris and
Anthocharis cardamines), the sexes differ either greatly or slightly in
colour.  No language suffices to describe the splendour of the males of
some tropical species.  Even within the same genus we often find species
presenting extraordinary differences between the sexes, whilst others have
their sexes closely alike.  Thus in the South American genus Epicalia, Mr.
Bates, to whom I am indebted for most of the following facts, and for
looking over this whole discussion, informs me that he knows twelve
species, the two sexes of which haunt the same stations (and this is not
always the case with butterflies), and which, therefore, cannot have been
differently affected by external conditions.  (5.  See also Mr. Bates's
paper in 'Proc. Ent. Soc. of Philadelphia,' 1865, p. 206.  Also Mr. Wallace
on the same subject, in regard to Diadema, in 'Transactions, Entomological
Society of London,' 1869, p. 278.)  In nine of these twelve species the
males rank amongst the most brilliant of all butterflies, and differ so
greatly from the comparatively plain females that they were formerly placed
in distinct genera.  The females of these nine species resemble each other
in their general type of coloration; and they likewise resemble both sexes
of the species in several allied genera found in various parts of the
world.  Hence we may infer that these nine species, and probably all the
others of the genus, are descended from an ancestral form which was
coloured in nearly the same manner.  In the tenth species the female still
retains the same general colouring, but the male resembles her, so that he
is coloured in a much less gaudy and contrasted manner than the males of
the previous species.  In the eleventh and twelfth species, the females
depart from the usual type, for they are gaily decorated almost like the
males, but in a somewhat less degree.  Hence in these two latter species
the bright colours of the males seem to have been transferred to the
females; whilst in the tenth species the male has either retained or
recovered the plain colours of the female, as well as of the parent-form of
the genus.  The sexes in these three cases have thus been rendered nearly
alike, though in an opposite manner.  In the allied genus Eubagis, both
sexes of some of the species are plain-coloured and nearly alike; whilst
with the greater number the males are decorated with beautiful metallic
tints in a diversified manner, and differ much from their females.  The
females throughout the genus retain the same general style of colouring, so
that they resemble one another much more closely than they resemble their
own males.

In the genus Papilio, all the species of the Aeneas group are remarkable
for their conspicuous and strongly contrasted colours, and they illustrate
the frequent tendency to gradation in the amount of difference between the
sexes.  In a few species, for instance in P. ascanius, the males and
females are alike; in others the males are either a little brighter, or
very much more superb than the females.  The genus Junonia, allied to our
Vanessae, offers a nearly parallel case, for although the sexes of most of
the species resemble each other, and are destitute of rich colours, yet in
certain species, as in J. oenone, the male is rather more bright-coloured
than the female, and in a few (for instance J. andremiaja) the male is so
different from the female that he might be mistaken for an entirely
distinct species.

Another striking case was pointed out to me in the British Museum by Mr. A.
Butler, namely, one of the tropical American Theclae, in which both sexes
are nearly alike and wonderfully splendid; in another species the male is
coloured in a similarly gorgeous manner, whilst the whole upper surface of
the female is of a dull uniform brown.  Our common little English blue
butterflies of the genus Lycaena, illustrate the various differences in
colour between the sexes, almost as well, though not in so striking a
manner, as the above exotic genera.  In Lycaena agestis both sexes have
wings of a brown colour, bordered with small ocellated orange spots, and
are thus alike.  In L. oegon the wings of the males are of a fine blue,
bordered with black, whilst those of the female are brown, with a similar
border, closely resembling the wings of L. agestis.  Lastly, in L. arion
both sexes are of a blue colour and are very like, though in the female the
edges of the wings are rather duskier, with the black spots plainer; and in
a bright blue Indian species both sexes are still more alike.

I have given the foregoing details in order to shew, in the first place,
that when the sexes of butterflies differ, the male as a general rule is
the more beautiful, and departs more from the usual type of colouring of
the group to which the species belongs.  Hence in most groups the females
of the several species resemble each other much more closely than do the
males.  In some cases, however, to which I shall hereafter allude, the
females are coloured more splendidly than the males.  In the second place,
these details have been given to bring clearly before the mind that within
the same genus, the two sexes frequently present every gradation from no
difference in colour, to so great a difference that it was long before the
two were placed by entomologists in the same genus.  In the third place, we
have seen that when the sexes nearly resemble each other, this appears due
either to the male having transferred his colours to the female, or to the
male having retained, or perhaps recovered, the primordial colours of the
group.  It also deserves notice that in those groups in which the sexes
differ, the females usually somewhat resemble the males, so that when the
males are beautiful to an extraordinary degree, the females almost
invariably exhibit some degree of beauty.  From the many cases of gradation
in the amount of difference between the sexes, and from the prevalence of
the same general type of coloration throughout the whole of the same group,
we may conclude that the causes have generally been the same which have
determined the brilliant colouring of the males alone of some species, and
of both sexes of other species.

As so many gorgeous butterflies inhabit the tropics, it has often been
supposed that they owe their colours to the great heat and moisture of
these zones; but Mr. Bates (6.  'The Naturalist on the Amazons,' vol. i.
1863, p. 19.) has shown by the comparison of various closely-allied groups
of insects from the temperate and tropical regions, that this view cannot
be maintained; and the evidence becomes conclusive when brilliantly-
coloured males and plain-coloured females of the same species inhabit the
same district, feed on the same food, and follow exactly the same habits of
life.  Even when the sexes resemble each other, we can hardly believe that
their brilliant and beautifully-arranged colours are the purposeless result
of the nature of the tissues and of the action of the surrounding
conditions.

With animals of all kinds, whenever colour has been modified for some
special purpose, this has been, as far as we can judge, either for direct
or indirect protection, or as an attraction between the sexes.  With many
species of butterflies the upper surfaces of the wings are obscure; and
this in all probability leads to their escaping observation and danger.
But butterflies would be particularly liable to be attacked by their
enemies when at rest; and most kinds whilst resting raise their wings
vertically over their backs, so that the lower surface alone is exposed to
view.  Hence it is this side which is often coloured so as to imitate the
objects on which these insects commonly rest.  Dr. Rossler, I believe,
first noticed the similarity of the closed wings of certain Vanessae and
other butterflies to the bark of trees.  Many analogous and striking facts
could be given.  The most interesting one is that recorded by Mr. Wallace
(7.  See the interesting article in the 'Westminster Review,' July 1867, p.
10.  A woodcut of the Kallima is given by Mr. Wallace in 'Hardwicke's
Science Gossip,' September 1867, p. 196.) of a common Indian and Sumatran
butterfly (Kallima) which disappears like magic when it settles on a bush;
for it hides its head and antennae between its closed wings, which, in
form, colour and veining, cannot be distinguished from a withered leaf with
its footstalk.  In some other cases the lower surfaces of the wings are
brilliantly coloured, and yet are protective; thus in Thecla rubi the wings
when closed are of an emerald green, and resemble the young leaves of the
bramble, on which in spring this butterfly may often be seen seated.  It is
also remarkable that in very many species in which the sexes differ greatly
in colour on their upper surface, the lower surface is closely similar or
identical in both sexes, and serves as a protection.  (8.  Mr. G. Fraser,
in 'Nature,' April 1871, p. 489.)

Although the obscure tints both of the upper and under sides of many
butterflies no doubt serve to conceal them, yet we cannot extend this view
to the brilliant and conspicuous colours on the upper surface of such
species as our admiral and peacock Vanessae, our white cabbage-butterflies
(Pieris), or the great swallow-tail Papilio which haunts the open fens--for
these butterflies are thus rendered visible to every living creature.  In
these species both sexes are alike; but in the common brimstone butterfly
(Gonepteryx rhamni), the male is of an intense yellow, whilst the female is
much paler; and in the orange-tip (Anthocharis cardamines) the males alone
have their wings tipped with bright orange.  Both the males and females in
these cases are conspicuous, and it is not credible that their difference
in colour should stand in any relation to ordinary protection.  Prof.
Weismann remarks (9.  'Einfluss der Isolirung auf die Artbildung,' 1872, p.
58.), that the female of one of the Lycaenae expands her brown wings when
she settles on the ground, and is then almost invisible; the male, on the
other hand, as if aware of the danger incurred from the bright blue of the
upper surface of his wings, rests with them closed; and this shows that the
blue colour cannot be in any way protective.  Nevertheless, it is probable
that conspicuous colours are indirectly beneficial to many species, as a
warning that they are unpalatable.  For in certain other cases, beauty has
been gained through the imitation of other beautiful species, which inhabit
the same district and enjoy an immunity from attack by being in some way
offensive to their enemies; but then we have to account for the beauty of
the imitated species.

As Mr. Walsh has remarked to me, the females of our orange-tip butterfly,
above referred to, and of an American species (Anth. genutia) probably shew
us the primordial colours of the parent-species of the genus; for both
sexes of four or five widely-distributed species are coloured in nearly the
same manner.  As in several previous cases, we may here infer that it is
the males of Anth. cardamines and genutia which have departed from the
usual type of the genus.  In the Anth. sara from California, the orange-
tips to the wings have been partially developed in the female; but they are
paler than in the male, and slightly different in some other respects.  In
an allied Indian form, the Iphias glaucippe, the orange-tips are fully
developed in both sexes.  In this Iphias, as pointed out to me by Mr. A.
Butler, the under surface of the wings marvellously resembles a pale-
coloured leaf; and in our English orange-tip, the under surface resembles
the flower-head of the wild parsley, on which the butterfly often rests at
night.  (10.  See the interesting observations by T.W. Wood, 'The Student,'
Sept. 1868, p. 81.)  The same reason which compels us to believe that the
lower surfaces have here been coloured for the sake of protection, leads us
to deny that the wings have been tipped with bright orange for the same
purpose, especially when this character is confined to the males.

Most Moths rest motionless during the whole or greater part of the day with
their wings depressed; and the whole upper surface is often shaded and
coloured in an admirable manner, as Mr. Wallace has remarked, for escaping
detection.  The front-wings of the Bombycidae and Noctuidae (11.  Mr.
Wallace in 'Hardwicke's Science Gossip,' September 1867, p. 193.), when at
rest, generally overlap and conceal the hind-wings; so that the latter
might be brightly coloured without much risk; and they are in fact often
thus coloured.  During flight, moths would often be able to escape from
their enemies; nevertheless, as the hind-wings are then fully exposed to
view, their bright colours must generally have been acquired at some little
risk.  But the following fact shews how cautious we ought to be in drawing
conclusions on this head.  The common Yellow Under-wings (Triphaena) often
fly about during the day or early evening, and are then conspicuous from
the colour of their hind-wings.  It would naturally be thought that this
would be a source of danger; but Mr. J. Jenner Weir believes that it
actually serves them as a means of escape, for birds strike at these
brightly coloured and fragile surfaces, instead of at the body.  For
instance, Mr. Weir turned into his aviary a vigorous specimen of Triphaena
pronuba, which was instantly pursued by a robin; but the bird's attention
being caught by the coloured wings, the moth was not captured until after
about fifty attempts, and small portions of the wings were repeatedly
broken off.  He tried the same experiment, in the open air, with a swallow
and T. fimbria; but the large size of this moth probably interfered with
its capture.  (12.  See also, on this subject, Mr. Weir's paper in
'Transactions, Entomological Society,' 1869, p. 23.)  We are thus reminded
of a statement made by Mr. Wallace (13.  'Westminster Review,' July 1867,
p. 16.), namely, that in the Brazilian forests and Malayan islands, many
common and highly-decorated butterflies are weak flyers, though furnished
with a broad expanse of wing; and they "are often captured with pierced and
broken wings, as if they had been seized by birds, from which they had
escaped:  if the wings had been much smaller in proportion to the body, it
seems probable that the insect would more frequently have been struck or
pierced in a vital part, and thus the increased expanse of the wings may
have been indirectly beneficial."

DISPLAY.

The bright colours of many butterflies and of some moths are specially
arranged for display, so that they may be readily seen.  During the night
colours are not visible, and there can be no doubt that the nocturnal
moths, taken as a body, are much less gaily decorated than butterflies, all
of which are diurnal in their habits.  But the moths of certain families,
such as the Zygaenidae, several Sphingidae, Uraniidae, some Arctiidae and
Saturniidae, fly about during the day or early evening, and many of these
are extremely beautiful, being far brighter coloured than the strictly
nocturnal kinds.  A few exceptional cases, however, of bright-coloured
nocturnal species have been recorded.  (14.  For instance, Lithosia; but
Prof. Westwood ('Modern Class. of Insects,' vol. ii. p. 390) seems
surprised at this case.  On the relative colours of diurnal and nocturnal
Lepidoptera, see ibid. pp. 333 and 392; also Harris, 'Treatise on the
Insects of New England,' 1842, p. 315.)

There is evidence of another kind in regard to display.  Butterflies, as
before remarked, elevate their wings when at rest, but whilst basking in
the sunshine often alternately raise and depress them, thus exposing both
surfaces to full view; and although the lower surface is often coloured in
an obscure manner as a protection, yet in many species it is as highly
decorated as the upper surface, and sometimes in a very different manner.
In some tropical species the lower surface is even more brilliantly
coloured than the upper.  (15.  Such differences between the upper and
lower surfaces of the wings of several species of Papilio may be seen in
the beautiful plates to Mr. Wallace's 'Memoir on the Papilionidae of the
Malayan Region,' in 'Transactions of the Linnean Society,' vol. xxv. part
i. 1865.)  In the English fritillaries (Argynnis) the lower surface alone
is ornamented with shining silver.  Nevertheless, as a general rule, the
upper surface, which is probably more fully exposed, is coloured more
brightly and diversely than the lower.  Hence the lower surface generally
affords to entomologists the more useful character for detecting the
affinities of the various species.  Fritz Mueller informs me that three
species of Castnia are found near his house in S. Brazil:  of two of them
the hind-wings are obscure, and are always covered by the front-wings when
these butterflies are at rest; but the third species has black hind-wings,
beautifully spotted with red and white, and these are fully expanded and
displayed whenever the butterfly rests.  Other such cases could be added.

If we now turn to the enormous group of moths, which, as I hear from Mr.
Stainton, do not habitually expose the under surface of their wings to full
view, we find this side very rarely coloured with a brightness greater
than, or even equal to, that of the upper side.  Some exceptions to the
rule, either real or apparent, must be noticed, as the case of Hypopyra.
(16.  See Mr. Wormald on this moth:  'Proceedings of the Entomological
Society,' March 2, 1868.)  Mr. Trimen informs me that in Guenee's great
work, three moths are figured, in which the under surface is much the more
brilliant.  For instance, in the Australian Gastrophora the upper surface
of the fore-wing is pale greyish-ochreous, while the lower surface is
magnificently ornamented by an ocellus of cobalt-blue, placed in the midst
of a black mark, surrounded by orange-yellow, and this by bluish-white.
But the habits of these three moths are unknown; so that no explanation can
be given of their unusual style of colouring.  Mr. Trimen also informs me
that the lower surface of the wings in certain other Geometrae (17.  See
also an account of the S. American genus Erateina (one of the Geometrae) in
'Transactions, Ent. Soc.' new series, vol. v. pl. xv. and xvi.) and
quadrifid Noctuae are either more variegated or more brightly-coloured than
the upper surface; but some of these species have the habit of "holding
their wings quite erect over their backs, retaining them in this position
for a considerable time," and thus exposing the under surface to view.
Other species, when settled on the ground or herbage, now and then suddenly
and slightly lift up their wings.  Hence the lower surface of the wings
being brighter than the upper surface in certain moths is not so anomalous
as it at first appears.  The Saturniidae include some of the most beautiful
of all moths, their wings being decorated, as in our British Emperor moth,
with fine ocelli; and Mr. T.W. Wood (18.  'Proc Ent. Soc. of London,' July
6, 1868, p. xxvii.) observes that they resemble butterflies in some of
their movements; "for instance, in the gentle waving up and down of the
wings as if for display, which is more characteristic of diurnal than of
nocturnal Lepidoptera."

It is a singular fact that no British moths which are brilliantly coloured,
and, as far as I can discover, hardly any foreign species, differ much in
colour according to sex; though this is the case with many brilliant
butterflies.  The male, however, of one American moth, the Saturnia Io, is
described as having its fore-wings deep yellow, curiously marked with
purplish-red spots; whilst the wings of the female are purple-brown, marked
with grey lines.  (19.  Harris, 'Treatise,' etc., edited by Flint, 1862, p.
395.)  The British moths which differ sexually in colour are all brown, or
of various dull yellow tints, or nearly white.  In several species the
males are much darker than the females (20.  For instance, I observe in my
son's cabinet that the males are darker than the females in the Lasiocampa
quercus, Odonestis potatoria, Hypogymna dispar, Dasychira pudibunda, and
Cycnia mendica.  In this latter species the difference in colour between
the two sexes is strongly marked; and Mr. Wallace informs me that we here
have, as he believes, an instance of protective mimicry confined to one
sex, as will hereafter be more fully explained.  The white female of the
Cycnia resembles the very common Spilosoma menthrasti, both sexes of which
are white; and Mr. Stainton observed that this latter moth was rejected
with utter disgust by a whole brood of young turkeys, which were fond of
eating other moths; so that if the Cycnia was commonly mistaken by British
birds for the Spilosoma, it would escape being devoured, and its white
deceptive colour would thus be highly beneficial.), and these belong to
groups which generally fly about during the afternoon.  On the other hand,
in many genera, as Mr. Stainton informs me, the males have the hind-wings
whiter than those of the female--of which fact Agrotis exclamationis offers
a good instance.  In the Ghost Moth (Hepialus humuli) the difference is
more strongly marked; the males being white, and the females yellow with
darker markings.  (21.  It is remarkable, that in the Shetland Islands the
male of this moth, instead of differing widely from the female, frequently
resembles her closely in colour (see Mr. MacLachlan, 'Transactions,
Entomological Society,' vol. ii. 1866, p. 459).  Mr. G. Fraser suggests
('Nature,' April 1871, p. 489) that at the season of the year when the
ghost-moth appears in these northern islands, the whiteness of the males
would not be needed to render them visible to the females in the twilight
night.)  It is probable that in these cases the males are thus rendered
more conspicuous, and more easily seen by the females whilst flying about
in the dusk.

From the several foregoing facts it is impossible to admit that the
brilliant colours of butterflies, and of some few moths, have commonly been
acquired for the sake of protection.  We have seen that their colours and
elegant patterns are arranged and exhibited as if for display.  Hence I am
led to believe that the females prefer or are most excited by the more
brilliant males; for on any other supposition the males would, as far as we
can see, be ornamented to no purpose.  We know that ants and certain
Lamellicorn beetles are capable of feeling an attachment for each other,
and that ants recognise their fellows after an interval of several months.
Hence there is no abstract improbability in the Lepidoptera, which probably
stand nearly or quite as high in the scale as these insects, having
sufficient mental capacity to admire bright colours.  They certainly
discover flowers by colour.  The Humming-bird Sphinx may often be seen to
swoop down from a distance on a bunch of flowers in the midst of green
foliage; and I have been assured by two persons abroad, that these moths
repeatedly visit flowers painted on the walls of a room, and vainly
endeavour to insert their proboscis into them.  Fritz Mueller informs me
that several kinds of butterflies in S. Brazil shew an unmistakable
preference for certain colours over others:  he observed that they very
often visited the brilliant red flowers of five or six genera of plants,
but never the white or yellow flowering species of the same and other
genera, growing in the same garden; and I have received other accounts to
the same effect.  As I hear from Mr. Doubleday, the common white butterfly
often flies down to a bit of paper on the ground, no doubt mistaking it for
one of its own species.  Mr. Collingwood (22.  'Rambles of a Naturalist in
the Chinese Seas,' 1868, p. 182.) in speaking of the difficulty in
collecting certain butterflies in the Malay Archipelago, states that "a
dead specimen pinned upon a conspicuous twig will often arrest an insect of
the same species in its headlong flight, and bring it down within easy
reach of the net, especially if it be of the opposite sex."

The courtship of butterflies is, as before remarked, a prolonged affair.
The males sometimes fight together in rivalry; and many may be seen
pursuing or crowding round the same female.  Unless, then, the females
prefer one male to another, the pairing must be left to mere chance, and
this does not appear probable.  If, on the other band, the females
habitually, or even occasionally, prefer the more beautiful males, the
colours of the latter will have been rendered brighter by degrees, and will
have been transmitted to both sexes or to one sex, according to the law of
inheritance which has prevailed.  The process of sexual selection will have
been much facilitated, if the conclusion can be trusted, arrived at from
various kinds of evidence in the supplement to the ninth chapter; namely,
that the males of many Lepidoptera, at least in the imago state, greatly
exceed the females in number.

Some facts, however, are opposed to the belief that female butterflies
prefer the more beautiful males; thus, as I have been assured by several
collectors, fresh females may frequently be seen paired with battered,
faded, or dingy males; but this is a circumstance which could hardly fail
often to follow from the males emerging from their cocoons earlier than the
females.  With moths of the family of the Bombycidae, the sexes pair
immediately after assuming the imago state; for they cannot feed, owing to
the rudimentary condition of their mouths.  The females, as several
entomologists have remarked to me, lie in an almost torpid state, and
appear not to evince the least choice in regard to their partners.  This is
the case with the common silk-moth (B. mori), as I have been told by some
continental and English breeders.  Dr. Wallace, who has had great
experience in breeding Bombyx cynthia, is convinced that the females evince
no choice or preference.  He has kept above 300 of these moths together,
and has often found the most vigorous females mated with stunted males.
The reverse appears to occur seldom; for, as he believes, the more vigorous
males pass over the weakly females, and are attracted by those endowed with
most vitality.  Nevertheless, the Bombycidae, though obscurely-coloured,
are often beautiful to our eyes from their elegant and mottled shades.

I have as yet only referred to the species in which the males are brighter
coloured than the females, and I have attributed their beauty to the
females for many generations having chosen and paired with the more
attractive males.  But converse cases occur, though rarely, in which the
females are more brilliant than the males; and here, as I believe, the
males have selected the more beautiful females, and have thus slowly added
to their beauty.  We do not know why in various classes of animals the
males of some few species have selected the more beautiful females instead
of having gladly accepted any female, as seems to be the general rule in
the animal kingdom:  but if, contrary to what generally occurs with the
Lepidoptera, the females were much more numerous than the males, the latter
would be likely to pick out the more beautiful females.  Mr. Butler shewed
me several species of Callidryas in the British Museum, in some of which
the females equalled, and in others greatly surpassed the males in beauty;
for the females alone have the borders of their wings suffused with crimson
and orange, and spotted with black.  The plainer males of these species
closely resemble each other, shewing that here the females have been
modified; whereas in those cases, where the males are the more ornate, it
is these which have been modified, the females remaining closely alike.

In England we have some analogous cases, though not so marked.  The females
alone of two species of Thecla have a bright-purple or orange patch on
their fore-wings.  In Hipparchia the sexes do not differ much; but it is
the female of H. janira which has a conspicuous light-brown patch on her
wings; and the females of some of the other species are brighter coloured
than their males.  Again, the females of Colias edusa and hyale have
"orange or yellow spots on the black marginal border, represented in the
males only by thin streaks"; and in Pieris it is the females which "are
ornamented with black spots on the fore-wings, and these are only partially
present in the males."  Now the males of many butterflies are known to
support the females during their marriage flight; but in the species just
named it is the females which support the males; so that the part which the
two sexes play is reversed, as is their relative beauty.  Throughout the
animal kingdom the males commonly take the more active share in wooing, and
their beauty seems to have been increased by the females having accepted
the more attractive individuals; but with these butterflies, the females
take the more active part in the final marriage ceremony, so that we may
suppose that they likewise do so in the wooing; and in this case we can
understand how it is that they have been rendered the more beautiful.  Mr.
Meldola, from whom the foregoing statements have been taken, says in
conclusion:  "Though I am not convinced of the action of sexual selection
in producing the colours of insects, it cannot be denied that these facts
are strikingly corroborative of Mr. Darwin's views."  (23.  'Nature,' April
27, 1871, p. 508.  Mr. Meldola quotes Donzel, in 'Soc. Ent. de France,'
1837, p. 77, on the flight of butterflies whilst pairing.  See also Mr. G.
Fraser, in 'Nature,' April 20, 1871, p. 489, on the sexual differences of
several British butterflies.)

As sexual selection primarily depends on variability, a few words must be
added on this subject.  In respect to colour there is no difficulty, for
any number of highly variable Lepidoptera could be named.  One good
instance will suffice.  Mr. Bates shewed me a whole series of specimens of
Papilio sesostris and P. childrenae; in the latter the males varied much in
the extent of the beautifully enamelled green patch on the fore-wings, and
in the size of the white mark, and of the splendid crimson stripe on the
hind-wings; so that there was a great contrast amongst the males between
the most and the least gaudy.  The male of Papilio sesostris is much less
beautiful than of P. childrenae; and it likewise varies a little in the
size of the green patch on the fore-wings, and in the occasional appearance
of the small crimson stripe on the hind-wings, borrowed, as it would seem,
from its own female; for the females of this and of many other species in
the Aeneas group possess this crimson stripe.  Hence between the brightest
specimens of P. sesostris and the dullest of P. childrenae, there was but a
small interval; and it was evident that as far as mere variability is
concerned, there would be no difficulty in permanently increasing the
beauty of either species by means of selection.  The variability is here
almost confined to the male sex; but Mr. Wallace and Mr. Bates have shewn
(24.  Wallace on the Papilionidae of the Malayan Region, in 'Transact.
Linn. Soc.' vol. xxv. 1865, pp. 8, 36.  A striking case of a rare variety,
strictly intermediate between two other well-marked female varieties, is
given by Mr. Wallace.  See also Mr. Bates, in 'Proc. Entomolog. Soc.' Nov.
19, 1866, p. xl.) that the females of some species are extremely variable,
the males being nearly constant.  In a future chapter I shall have occasion
to shew that the beautiful eye-like spots, or ocelli, found on the wings of
many Lepidoptera, are eminently variable.  I may here add that these ocelli
offer a difficulty on the theory of sexual selection; for though appearing
to us so ornamental, they are never present in one sex and absent in the
other, nor do they ever differ much in the two sexes.  (25.  Mr. Bates was
so kind as to lay this subject before the Entomological Society, and I have
received answers to this effect from several entomologists.)  This fact is
at present inexplicable; but if it should hereafter be found that the
formation of an ocellus is due to some change in the tissues of the wings,
for instance, occurring at a very early period of development, we might
expect, from what we know of the laws of inheritance, that it would be
transmitted to both sexes, though arising and perfected in one sex alone.

On the whole, although many serious objections may be urged, it seems
probable that most of the brilliantly-coloured species of Lepidoptera owe
their colours to sexual selection, excepting in certain cases, presently to
be mentioned, in which conspicuous colours have been gained through mimicry
as a protection.  From the ardour of the male throughout the animal
kingdom, he is generally willing to accept any female; and it is the female
which usually exerts a choice.  Hence, if sexual selection has been
efficient with the Lepidoptera, the male, when the sexes differ, ought to
be the more brilliantly coloured, and this undoubtedly is the case.  When
both sexes are brilliantly coloured and resemble each other, the characters
acquired by the males appear to have been transmitted to both.  We are led
to this conclusion by cases, even within the same genus, of gradation from
an extraordinary amount of difference to identity in colour between the two
sexes.

But it may be asked whether the difference in colour between the sexes may
not be accounted for by other means besides sexual selection.  Thus the
males and females of the same species of butterfly are in several cases
known (26.  H.W. Bates, 'The Naturalist on the Amazons,' vol. ii. 1863, p.
228.  A.R. Wallace, in 'Transactions, Linnean Society,' vol. xxv. 1865, p.
10.) to inhabit different stations, the former commonly basking in the
sunshine, the latter haunting gloomy forests.  It is therefore possible
that different conditions of life may have acted directly on the two sexes;
but this is not probable (27.  On this whole subject see 'The Variation of
Animals and Plants under Domestication,' 1868, vol. ii. chap. xxiii.) as in
the adult state they are exposed to different conditions during a very
short period; and the larvae of both are exposed to the same conditions.
Mr. Wallace believes that the difference between the sexes is due not so
much to the males having been modified, as to the females having in all or
almost all cases acquired dull colours for the sake of protection.  It
seems to me, on the contrary, far more probable that it is the males which
have been chiefly modified through sexual selection, the females having
been comparatively little changed.  We can thus understand how it is that
the females of allied species generally resemble one another so much more
closely than do the males.  They thus shew us approximately the primordial
colouring of the parent-species of the group to which they belong.  They
have, however, almost always been somewhat modified by the transfer to them
of some of the successive variations, through the accumulation of which the
males were rendered beautiful.  But I do not wish to deny that the females
alone of some species may have been specially modified for protection.  In
most cases the males and females of distinct species will have been exposed
during their prolonged larval state to different conditions, and may have
been thus affected; though with the males any slight change of colour thus
caused will generally have been masked by the brilliant tints gained
through sexual selection.  When we treat of Birds, I shall have to discuss
the whole question, as to how far the differences in colour between the
sexes are due to the males having been modified through sexual selection
for ornamental purposes, or to the females having been modified through
natural selection for the sake of protection, so that I will here say but
little on the subject.

In all the cases in which the more common form of equal inheritance by both
sexes has prevailed, the selection of bright-coloured males would tend to
make the females bright-coloured; and the selection of dull-coloured
females would tend to make the males dull.  If both processes were carried
on simultaneously, they would tend to counteract each other; and the final
result would depend on whether a greater number of females from being well
protected by obscure colours, or a greater number of males by being
brightly-coloured and thus finding partners, succeeded in leaving more
numerous offspring.

In order to account for the frequent transmission of characters to one sex
alone, Mr. Wallace expresses his belief that the more common form of equal
inheritance by both sexes can be changed through natural selection into
inheritance by one sex alone, but in favour of this view I can discover no
evidence.  We know from what occurs under domestication that new characters
often appear, which from the first are transmitted to one sex alone; and by
the selection of such variations there would not be the slightest
difficulty in giving bright colours to the males alone, and at the same
time or subsequently, dull colours to the females alone.  In this manner
the females of some butterflies and moths have, it is probable, been
rendered inconspicuous for the sake of protection, and widely different
from their males.

I am, however, unwilling without distinct evidence to admit that two
complex processes of selection, each requiring the transference of new
characters to one sex alone, have been carried on with a multitude of
species,--that the males have been rendered more brilliant by beating their
rivals, and the females more dull-coloured by having escaped from their
enemies.  The male, for instance, of the common brimstone butterfly
(Gonepteryx), is of a far more intense yellow than the female, though she
is equally conspicuous; and it does not seem probable that she specially
acquired her pale tints as a protection, though it is probable that the
male acquired his bright colours as a sexual attraction.  The female of
Anthocharis cardamines does not possess the beautiful orange wing-tips of
the male; consequently she closely resembles the white butterflies (Pieris)
so common in our gardens; but we have no evidence that this resemblance is
beneficial to her.  As, on the other hand, she resembles both sexes of
several other species of the genus inhabiting various quarters of the
world, it is probable that she has simply retained to a large extent her
primordial colours.

Finally, as we have seen, various considerations lead to the conclusion
that with the greater number of brilliantly-coloured Lepidoptera it is the
male which has been chiefly modified through sexual selection; the amount
of difference between the sexes mostly depending on the form of inheritance
which has prevailed.  Inheritance is governed by so many unknown laws or
conditions, that it seems to us to act in a capricious manner (28.  The
'Variation of Animals and Plants under Domestication,' vol. ii. chap. xii.
p. 17.); and we can thus, to a certain extent, understand how it is that
with closely allied species the sexes either differ to an astonishing
degree, or are identical in colour.  As all the successive steps in the
process of variation are necessarily transmitted through the female, a
greater or less number of such steps might readily become developed in her;
and thus we can understand the frequent gradations from an extreme
difference to none at all between the sexes of allied species.  These cases
of gradation, it may be added, are much too common to favour the
supposition that we here see females actually undergoing the process of
transition and losing their brightness for the sake of protection; for we
have every reason to conclude that at any one time the greater number of
species are in a fixed condition.

MIMICRY.

This principle was first made clear in an admirable paper by Mr. Bates (29.
'Transact. Linn. Soc.' vol. xxiii. 1862, p. 495.), who thus threw a flood
of light on many obscure problems.  It had previously been observed that
certain butterflies in S. America belonging to quite distinct families,
resembled the Heliconidae so closely in every stripe and shade of colour,
that they could not be distinguished save by an experienced entomologist.
As the Heliconidae are coloured in their usual manner, whilst the others
depart from the usual colouring of the groups to which they belong, it is
clear that the latter are the imitators, and the Heliconidae the imitated.
Mr. Bates further observed that the imitating species are comparatively
rare, whilst the imitated abound, and that the two sets live mingled
together.  From the fact of the Heliconidae being conspicuous and beautiful
insects, yet so numerous in individuals and species, he concluded that they
must be protected from the attacks of enemies by some secretion or odour;
and this conclusion has now been amply confirmed (30.  'Proc. Entomological
Soc.' Dec. 3, 1866, p. xlv.), especially by Mr. Belt.  Hence Mr. Bates
inferred that the butterflies which imitate the protected species have
acquired their present marvellously deceptive appearance through variation
and natural selection, in order to be mistaken for the protected kinds, and
thus to escape being devoured.  No explanation is here attempted of the
brilliant colours of the imitated, but only of the imitating butterflies.
We must account for the colours of the former in the same general manner,
as in the cases previously discussed in this chapter.  Since the
publication of Mr. Bates' paper, similar and equally striking facts have
been observed by Mr. Wallace in the Malayan region, by Mr. Trimen in South
Africa, and by Mr. Riley in the United States.  (31.  Wallace, 'Transact.
Linn. Soc.' vol. xxv. 1865 p. i.; also, 'Transact. Ent. Soc.' vol. iv. (3rd
series), 1867, p. 301.  Trimen, 'Linn. Transact.' vol. xxvi. 1869, p. 497.
Riley, 'Third Annual Report on the Noxious Insects of Missouri,' 1871, pp.
163-168.  This latter essay is valuable, as Mr. Riley here discusses all
the objections which have been raised against Mr. Bates's theory.)

As some writers have felt much difficulty in understanding how the first
steps in the process of mimicry could have been effected through natural
selection, it may be well to remark that the process probably commenced
long ago between forms not widely dissimilar in colour.  In this case even
a slight variation would be beneficial, if it rendered the one species more
like the other; and afterwards the imitated species might be modified to an
extreme degree through sexual selection or other means, and if the changes
were gradual, the imitators might easily be led along the same track, until
they differed to an equally extreme degree from their original condition;
and they would thus ultimately assume an appearance or colouring wholly
unlike that of the other members of the group to which they belonged.  It
should also be remembered that many species of Lepidoptera are liable to
considerable and abrupt variations in colour.  A few instances have been
given in this chapter; and many more may be found in the papers of Mr.
Bates and Mr. Wallace.

With several species the sexes are alike, and imitate the two sexes of
another species.  But Mr. Trimen gives, in the paper already referred to,
three cases in which the sexes of the imitated form differ from each other
in colour, and the sexes of the imitating form differ in a like manner.
Several cases have also been recorded where the females alone imitate
brilliantly-coloured and protected species, the males retaining "the normal
aspect of their immediate congeners."  It is here obvious that the
successive variations by which the female has been modified have been
transmitted to her alone.  It is, however, probable that some of the many
successive variations would have been transmitted to, and developed in, the
males had not such males been eliminated by being thus rendered less
attractive to the females; so that only those variations were preserved
which were from the first strictly limited in their transmission to the
female sex.  We have a partial illustration of these remarks in a statement
by Mr. Belt (32.  'The Naturalist in Nicaragua,' 1874, p. 385.); that the
males of some of the Leptalides, which imitate protected species, still
retain in a concealed manner some of their original characters.  Thus in
the males "the upper half of the lower wing is of a pure white, whilst all
the rest of the wings is barred and spotted with black, red and yellow,
like the species they mimic.  The females have not this white patch, and
the males usually conceal it by covering it with the upper wing, so that I
cannot imagine its being of any other use to them than as an attraction in
courtship, when they exhibit it to the females, and thus gratify their
deep-seated preference for the normal colour of the Order to which the
Leptalides belong."

BRIGHT COLOURS OF CATERPILLARS.

Whilst reflecting on the beauty of many butterflies, it occurred to me that
some caterpillars were splendidly coloured; and as sexual selection could
not possibly have here acted, it appeared rash to attribute the beauty of
the mature insect to this agency, unless the bright colours of their larvae
could be somehow explained.  In the first place, it may be observed that
the colours of caterpillars do not stand in any close correlation with
those of the mature insect.  Secondly, their bright colours do not serve in
any ordinary manner as a protection.  Mr. Bates informs me, as an instance
of this, that the most conspicuous caterpillar which he ever beheld (that
of a Sphinx) lived on the large green leaves of a tree on the open llanos
of South America; it was about four inches in length, transversely banded
with black and yellow, and with its head, legs, and tail of a bright red.
Hence it caught the eye of any one who passed by, even at the distance of
many yards, and no doubt that of every passing bird.

I then applied to Mr. Wallace, who has an innate genius for solving
difficulties.  After some consideration he replied:  "Most caterpillars
require protection, as may be inferred from some kinds being furnished with
spines or irritating hairs, and from many being coloured green like the
leaves on which they feed, or being curiously like the twigs of the trees
on which they live."  Another instance of protection, furnished me by Mr.
J. Mansel Weale, may be added, namely, that there is a caterpillar of a
moth which lives on the mimosas in South Africa, and fabricates for itself
a case quite indistinguishable from the surrounding thorns.  From such
considerations Mr. Wallace thought it probable that conspicuously coloured
caterpillars were protected by having a nauseous taste; but as their skin
is extremely tender, and as their intestines readily protrude from a wound,
a slight peck from the beak of a bird would be as fatal to them as if they
had been devoured.  Hence, as Mr. Wallace remarks, "distastefulness alone
would be insufficient to protect a caterpillar unless some outward sign
indicated to its would-be destroyer that its prey was a disgusting morsel."
Under these circumstances it would be highly advantageous to a caterpillar
to be instantaneously and certainly recognised as unpalatable by all birds
and other animals.  Thus the most gaudy colours would be serviceable, and
might have been gained by variation and the survival of the most easily-
recognised individuals.

This hypothesis appears at first sight very bold, but when it was brought
before the Entomological Society (33.  'Proceedings, Entomological
Society,' Dec. 3, 1866, p. xlv. and March 4, 1867, p. lxxx.) it was
supported by various statements; and Mr. J. Jenner Weir, who keeps a large
number of birds in an aviary, informs me that he has made many trials, and
finds no exception to the rule, that all caterpillars of nocturnal and
retiring habits with smooth skins, all of a green colour, and all which
imitate twigs, are greedily devoured by his birds.  The hairy and spinose
kinds are invariably rejected, as were four conspicuously-coloured species.
When the birds rejected a caterpillar, they plainly shewed, by shaking
their heads, and cleansing their beaks, that they were disgusted by the
taste.  (34.  See Mr. J. Jenner Weir's paper on Insects and Insectivorous
Birds, in 'Transact. Ent. Soc.' 1869, p. 21; also Mr. Butler's paper, ibid.
p. 27.  Mr. Riley has given analogous facts in the 'Third Annual Report on
the Noxious Insects of Missouri,' 1871, p. 148.  Some opposed cases are,
however, given by Dr. Wallace and M. H. d'Orville; see 'Zoological Record,'
1869, p. 349.)  Three conspicuous kinds of caterpillars and moths were also
given to some lizards and frogs, by Mr. A. Butler, and were rejected,
though other kinds were eagerly eaten.  Thus the probability of Mr.
Wallace's view is confirmed, namely, that certain caterpillars have been
made conspicuous for their own good, so as to be easily recognised by their
enemies, on nearly the same principle that poisons are sold in coloured
bottles by druggists for the good of man.  We cannot, however, at present
thus explain the elegant diversity in the colours of many caterpillars; but
any species which had at some former period acquired a dull, mottled, or
striped appearance, either in imitation of surrounding objects, or from the
direct action of climate, etc., almost certainly would not become uniform
in colour, when its tints were rendered intense and bright; for in order to
make a caterpillar merely conspicuous, there would be no selection in any
definite direction.

SUMMARY AND CONCLUDING REMARKS ON INSECTS.

Looking back to the several Orders, we see that the sexes often differ in
various characters, the meaning of which is not in the least understood.
The sexes, also, often differ in their organs of sense and means of
locomotion, so that the males may quickly discover and reach the females.
They differ still oftener in the males possessing diversified contrivances
for retaining the females when found.  We are, however, here concerned only
in a secondary degree with sexual differences of these kinds.

In almost all the Orders, the males of some species, even of weak and
delicate kinds, are known to be highly pugnacious; and some few are
furnished with special weapons for fighting with their rivals.  But the law
of battle does not prevail nearly so widely with insects as with the higher
animals.  Hence it probably arises, that it is in only a few cases that the
males have been rendered larger and stronger than the females.  On the
contrary, they are usually smaller, so that they may be developed within a
shorter time, to be ready in large numbers for the emergence of the
females.

In two families of the Homoptera and in three of the Orthoptera, the males
alone possess sound-producing organs in an efficient state.  These are used
incessantly during the breeding-season, not only for calling the females,
but apparently for charming or exciting them in rivalry with other males.
No one who admits the agency of selection of any kind, will, after reading
the above discussion, dispute that these musical instruments have been
acquired through sexual selection.  In four other Orders the members of one
sex, or more commonly of both sexes, are provided with organs for producing
various sounds, which apparently serve merely as call-notes.  When both
sexes are thus provided, the individuals which were able to make the
loudest or most continuous noise would gain partners before those which
were less noisy, so that their organs have probably been gained through
sexual selection.  It is instructive to reflect on the wonderful diversity
of the means for producing sound, possessed by the males alone, or by both
sexes, in no less than six Orders.  We thus learn how effectual sexual
selection has been in leading to modifications which sometimes, as with the
Homoptera, relate to important parts of the organisation.

From the reasons assigned in the last chapter, it is probable that the
great horns possessed by the males of many Lamellicorn, and some other
beetles, have been acquired as ornaments.  From the small size of insects,
we are apt to undervalue their appearance.  If we could imagine a male
Chalcosoma (Fig. 16), with its polished bronzed coat of mail, and its vast
complex horns, magnified to the size of a horse, or even of a dog, it would
be one of the most imposing animals in the world.

The colouring of insects is a complex and obscure subject.  When the male
differs slightly from the female, and neither are brilliantly-coloured, it
is probable that the sexes have varied in a slightly different manner, and
that the variations have been transmitted by each sex to the same without
any benefit or evil thus accruing.  When the male is brilliantly-coloured
and differs conspicuously from the female, as with some dragon-flies and
many butterflies, it is probable that he owes his colours to sexual
selection; whilst the female has retained a primordial or very ancient type
of colouring, slightly modified by the agencies before explained.  But in
some cases the female has apparently been made obscure by variations
transmitted to her alone, as a means of direct protection; and it is almost
certain that she has sometimes been made brilliant, so as to imitate other
protected species inhabiting the same district.  When the sexes resemble
each other and both are obscurely coloured, there is no doubt that they
have been in a multitude of cases so coloured for the sake of protection.
So it is in some instances when both are brightly-coloured, for they thus
imitate protected species, or resemble surrounding objects such as flowers;
or they give notice to their enemies that they are unpalatable.  In other
cases in which the sexes resemble each other and are both brilliant,
especially when the colours are arranged for display, we may conclude that
they have been gained by the male sex as an attraction, and have been
transferred to the female.  We are more especially led to this conclusion
whenever the same type of coloration prevails throughout a whole group, and
we find that the males of some species differ widely in colour from the
females, whilst others differ slightly or not at all with intermediate
gradations connecting these extreme states.

In the same manner as bright colours have often been partially transferred
from the males to the females, so it has been with the extraordinary horns
of many Lamellicorn and some other beetles.  So again, the sound-producing
organs proper to the males of the Homoptera and Orthoptera have generally
been transferred in a rudimentary, or even in a nearly perfect condition,
to the females; yet not sufficiently perfect to be of any use.  It is also
an interesting fact, as bearing on sexual selection, that the stridulating
organs of certain male Orthoptera are not fully developed until the last
moult; and that the colours of certain male dragon-flies are not fully
developed until some little time after their emergence from the pupal
state, and when they are ready to breed.

Sexual selection implies that the more attractive individuals are preferred
by the opposite sex; and as with insects, when the sexes differ, it is the
male which, with some rare exceptions, is the more ornamented, and departs
more from the type to which the species belongs;--and as it is the male
which searches eagerly for the female, we must suppose that the females
habitually or occasionally prefer the more beautiful males, and that these
have thus acquired their beauty.  That the females in most or all the
Orders would have the power of rejecting any particular male, is probable
from the many singular contrivances possessed by the males, such as great
jaws, adhesive cushions, spines, elongated legs, etc., for seizing the
female; for these contrivances show that there is some difficulty in the
act, so that her concurrence would seem necessary.  Judging from what we
know of the perceptive powers and affections of various insects, there is
no antecedent improbability in sexual selection having come largely into
play; but we have as yet no direct evidence on this head, and some facts
are opposed to the belief.  Nevertheless, when we see many males pursuing
the same female, we can hardly believe that the pairing is left to blind
chance--that the female exerts no choice, and is not influenced by the
gorgeous colours or other ornaments with which the male is decorated.

If we admit that the females of the Homoptera and Orthoptera appreciate the
musical tones of their male partners, and that the various instruments have
been perfected through sexual selection, there is little improbability in
the females of other insects appreciating beauty in form or colour, and
consequently in such characters having been thus gained by the males.  But
from the circumstance of colour being so variable, and from its having been
so often modified for the sake of protection, it is difficult to decide in
how large a proportion of cases sexual selection has played a part.  This
is more especially difficult in those Orders, such as Orthoptera,
Hymenoptera, and Coleoptera, in which the two sexes rarely differ much in
colour; for we are then left to mere analogy.  With the Coleoptera,
however, as before remarked, it is in the great Lamellicorn group, placed
by some authors at the head of the Order, and in which we sometimes see a
mutual attachment between the sexes, that we find the males of some species
possessing weapons for sexual strife, others furnished with wonderful
horns, many with stridulating organs, and others ornamented with splendid
metallic tints.  Hence it seems probable that all these characters have
been gained through the same means, namely sexual selection.  With
butterflies we have the best evidence, as the males sometimes take pains to
display their beautiful colours; and we cannot believe that they would act
thus, unless the display was of use to them in their courtship.

When we treat of Birds, we shall see that they present in their secondary
sexual characters the closest analogy with insects.  Thus, many male birds
are highly pugnacious, and some are furnished with special weapons for
fighting with their rivals.  They possess organs which are used during the
breeding-season for producing vocal and instrumental music.  They are
frequently ornamented with combs, horns, wattles and plumes of the most
diversified kinds, and are decorated with beautiful colours, all evidently
for the sake of display.  We shall find that, as with insects, both sexes
in certain groups are equally beautiful, and are equally provided with
ornaments which are usually confined to the male sex.  In other groups both
sexes are equally plain-coloured and unornamented.  Lastly, in some few
anomalous cases, the females are more beautiful than the males.  We shall
often find, in the same group of birds, every gradation from no difference
between the sexes, to an extreme difference.  We shall see that female
birds, like female insects, often possess more or less plain traces or
rudiments of characters which properly belong to the males and are of use
only to them.  The analogy, indeed, in all these respects between birds and
insects is curiously close.  Whatever explanation applies to the one class
probably applies to the other; and this explanation, as we shall hereafter
attempt to shew in further detail, is sexual selection.


CHAPTER XII.

SECONDARY SEXUAL CHARACTERS OF FISHES, AMPHIBIANS, AND REPTILES.

FISHES:   Courtship and battles of the males--Larger size of the females--
Males, bright colours and ornamental appendages; other strange characters--
Colours and appendages acquired by the males during the breeding-season
alone--Fishes with both sexes brilliantly coloured--Protective colours--The
less conspicuous colours of the female cannot be accounted for on the
principle of protection--Male fishes building nests, and taking charge of
the ova and young.

AMPHIBIANS:   Differences in structure and colour between the sexes--Vocal
organs.

REPTILES:   Chelonians--Crocodiles--Snakes, colours in some cases
protective--Lizards, battles of--Ornamental appendages--Strange differences
in structure between the sexes--Colours--Sexual differences almost as great
as with birds.

We have now arrived at the great sub-kingdom of the Vertebrata, and will
commence with the lowest class, that of fishes.  The males of Plagiostomous
fishes (sharks, rays) and of Chimaeroid fishes are provided with claspers
which serve to retain the female, like the various structures possessed by
many of the lower animals.  Besides the claspers, the males of many rays
have clusters of strong sharp spines on their heads, and several rows along
"the upper outer surface of their pectoral fins."  These are present in the
males of some species, which have other parts of their bodies smooth.  They
are only temporarily developed during the breeding-season; and Dr. Gunther
suspects that they are brought into action as prehensile organs by the
doubling inwards and downwards of the two sides of the body.  It is a
remarkable fact that the females and not the males of some species, as of
Raia clavata, have their backs studded with large hook-formed spines.  (1.
Yarrell's 'Hist. of British Fishes,' vol. ii. 1836, pp 417, 425, 436.  Dr.
Gunther informs me that the spines in R. clavata are peculiar to the
female.)

The males alone of the capelin (Mallotus villosus, one of Salmonidae), are
provided with a ridge of closely-set, brush-like scales, by the aid of
which two males, one on each side, hold the female, whilst she runs with
great swiftness on the sandy beach, and there deposits her spawn.  (2.  The
'American Naturalist,' April 1871, p. 119.)  The widely distinct
Monacanthus scopas presents a somewhat analogous structure.  The male, as
Dr. Gunther informs me, has a cluster of stiff, straight spines, like those
of a comb, on the sides of the tail; and these in a specimen six inches
long were nearly one and a half inches in length; the female has in the
same place a cluster of bristles, which may be compared with those of a
tooth-brush.  In another species, M. peronii, the male has a brush like
that possessed by the female of the last species, whilst the sides of the
tail in the female are smooth.  In some other species of the same genus the
tail can be perceived to be a little roughened in the male and perfectly
smooth in the female; and lastly in others, both sexes have smooth sides.

The males of many fish fight for the possession of the females.  Thus the
male stickleback (Gasterosteus leiurus) has been described as "mad with
delight," when the female comes out of her hiding-place and surveys the
nest which he has made for her.  "He darts round her in every direction,
then to his accumulated materials for the nest, then back again in an
instant; and as she does not advance he endeavours to push her with his
snout, and then tries to pull her by the tail and side-spine to the nest."
(3.  See Mr. R. Warington's interesting articles in 'Annals and Magazine of
Natural History,' October 1852, and November 1855.)  The males are said to
be polygamists (4.  Noel Humphreys, 'River Gardens,' 1857.); they are
extraordinarily bold and pugnacious, whilst "the females are quite
pacific."  Their battles are at times desperate; "for these puny combatants
fasten tight on each other for several seconds, tumbling over and over
again until their strength appears completely exhausted."  With the rough-
tailed stickleback (G. trachurus) the males whilst fighting swim round and
round each other, biting and endeavouring to pierce each other with their
raised lateral spines.  The same writer adds (5.  Loudon's 'Magazine of
Natural History,' vol. iii. 1830, p. 331.), "the bite of these little
furies is very severe.  They also use their lateral spines with such fatal
effect, that I have seen one during a battle absolutely rip his opponent
quite open, so that he sank to the bottom and died."  When a fish is
conquered, "his gallant bearing forsakes him; his gay colours fade away;
and he hides his disgrace among his peaceable companions, but is for some
time the constant object of his conqueror's persecution."

The male salmon is as pugnacious as the little stickleback; and so is the
male trout, as I hear from Dr. Gunther.  Mr. Shaw saw a violent contest
between two male salmon which lasted the whole day; and Mr. R. Buist,
Superintendent of Fisheries, informs me that he has often watched from the
bridge at Perth the males driving away their rivals, whilst the females
were spawning.  The males "are constantly fighting and tearing each other
on the spawning-beds, and many so injure each other as to cause the death
of numbers, many being seen swimming near the banks of the river in a state
of exhaustion, and apparently in a dying state."  (6.  The 'Field,' June
29, 1867.  For Mr. Shaw's Statement, see 'Edinburgh Review,' 1843.  Another
experienced observer (Scrope's 'Days of Salmon Fishing,' p. 60) remarks
that like the stag, the male would, if he could, keep all other males
away.)  Mr. Buist informs me, that in June 1868, the keeper of the
Stormontfield breeding-ponds visited the northern Tyne and found about 300
dead salmon, all of which with one exception were males; and he was
convinced that they had lost their lives by fighting.

[Fig. 27.  Head of male common salmon (Salmo salar) during the breeding-
season.
[This drawing, as well as all the others in the present chapter, have been
executed by the well-known artist, Mr. G. Ford, from specimens in the
British Museum, under the kind superintendence of Dr. Gunther.]

Fig. 28.  Head of female salmon.]

The most curious point about the male salmon is that during the breeding-
season, besides a slight change in colour, "the lower jaw elongates, and a
cartilaginous projection turns upwards from the point, which, when the jaws
are closed, occupies a deep cavity between the intermaxillary bones of the
upper jaw."  (7.  Yarrell, 'History of British Fishes,' vol. ii. 1836, p.
10.) (Figs. 27 and 28.)  In our salmon this change of structure lasts only
during the breeding-season; but in the Salmo lycaodon of N.W. America the
change, as Mr. J.K. Lord (8.  'The Naturalist in Vancouver's Island,' vol.
i. 1866, p. 54.) believes, is permanent, and best marked in the older males
which have previously ascended the rivers.  In these old males the jaw
becomes developed into an immense hook-like projection, and the teeth grow
into regular fangs, often more than half an inch in length.  With the
European salmon, according to Mr. Lloyd (9.  'Scandinavian Adventures,'
vol. i. 1854, pp. 100, 104.), the temporary hook-like structure serves to
strengthen and protect the jaws, when one male charges another with
wonderful violence; but the greatly developed teeth of the male American
salmon may be compared with the tusks of many male mammals, and they
indicate an offensive rather than a protective purpose.

The salmon is not the only fish in which the teeth differ in the two sexes;
as this is the case with many rays.  In the thornback (Raia clavata) the
adult male has sharp, pointed teeth, directed backwards, whilst those of
the female are broad and flat, and form a pavement; so that these teeth
differ in the two sexes of the same species more than is usual in distinct
genera of the same family.  The teeth of the male become sharp only when he
is adult:  whilst young they are broad and flat like those of the female.
As so frequently occurs with secondary sexual characters, both sexes of
some species of rays (for instance R. batis), when adult, possess sharp
pointed teeth; and here a character, proper to and primarily gained by the
male, appears to have been transmitted to the offspring of both sexes.  The
teeth are likewise pointed in both sexes of R. maculata, but only when
quite adult; the males acquiring them at an earlier age than the females.
We shall hereafter meet with analogous cases in certain birds, in which the
male acquires the plumage common to both sexes when adult, at a somewhat
earlier age than does the female.  With other species of rays the males
even when old never possess sharp teeth, and consequently the adults of
both sexes are provided with broad, flat teeth like those of the young, and
like those of the mature females of the above-mentioned species.  (10.  See
Yarrell's account of the rays in his 'History of British Fishes,' vol. ii.
1836, p. 416, with an excellent figure, and pp. 422, 432.)  As the rays are
bold, strong and voracious fish, we may suspect that the males require
their sharp teeth for fighting with their rivals; but as they possess many
parts modified and adapted for the prehension of the female, it is possible
that their teeth may be used for this purpose.

In regard to size, M. Carbonnier (11.  As quoted in 'The Farmer,' 1868, p.
369.) maintains that the female of almost all fishes is larger than the
male; and Dr. Gunther does not know of a single instance in which the male
is actually larger than the female.  With some Cyprinodonts the male is not
even half as large.  As in many kinds of fishes the males habitually fight
together, it is surprising that they have not generally become larger and
stronger than the females through the effects of sexual selection.  The
males suffer from their small size, for according to M. Carbonnier, they
are liable to be devoured by the females of their own species when
carnivorous, and no doubt by other species.  Increased size must be in some
manner of more importance to the females, than strength and size are to the
males for fighting with other males; and this perhaps is to allow of the
production of a vast number of ova.

[Fig. 29.  Callionymus lyra.
Upper figure, male;
lower figure, female.
N.B.  The lower figure is more reduced than the upper.]

In many species the male alone is ornamented with bright colours; or these
are much brighter in the male than the female.  The male, also, is
sometimes provided with appendages which appear to be of no more use to him
for the ordinary purposes of life, than are the tail feathers to the
peacock.  I am indebted for most of the following facts to the kindness of
Dr. Gunther.  There is reason to suspect that many tropical fishes differ
sexually in colour and structure; and there are some striking cases with
our British fishes.  The male Callionymus lyra has been called the gemmeous
dragonet "from its brilliant gem-like colours."  When fresh caught from the
sea the body is yellow of various shades, striped and spotted with vivid
blue on the head; the dorsal fins are pale brown with dark longitudinal
bands; the ventral, caudal, and anal fins being bluish-black.  The female,
or sordid dragonet, was considered by Linnaeus, and by many subsequent
naturalists, as a distinct species; it is of a dingy reddish-brown, with
the dorsal fin brown and the other fins white.  The sexes differ also in
the proportional size of the head and mouth, and in the position of the
eyes (12.  I have drawn up this description from Yarrell's 'British
Fishes,' vol. i. 1836, pp. 261 and 266.); but the most striking difference
is the extraordinary elongation in the male (Fig. 29) of the dorsal fin.
Mr. W. Saville Kent remarks that this "singular appendage appears from my
observations of the species in confinement, to be subservient to the same
end as the wattles, crests, and other abnormal adjuncts of the male in
gallinaceous birds, for the purpose of fascinating their mates."  (13.
'Nature,' July 1873, p. 264.)  The young males resemble the adult females
in structure and colour.  Throughout the genus Callionymus (14.  'Catalogue
of Acanth. Fishes in the British Museum,' by Dr. Gunther, 1861, pp. 138-
151.), the male is generally much more brightly spotted than the female,
and in several species, not only the dorsal, but the anal fin is much
elongated in the males.

The male of the Cottus scorpius, or sea-scorpion, is slenderer and smaller
than the female.  There is also a great difference in colour between them.
It is difficult, as Mr. Lloyd (15.  'Game Birds of Sweden,' etc., 1867, p.
466.) remarks, "for any one, who has not seen this fish during the
spawning-season, when its hues are brightest, to conceive the admixture of
brilliant colours with which it, in other respects so ill-favoured, is at
that time adorned."  Both sexes of the Labrus mixtus, although very
different in colour, are beautiful; the male being orange with bright blue
stripes, and the female bright red with some black spots on the back.

[Fig. 30.  Xiphophorus Hellerii.
Upper figure, male;
lower figure, female.]

In the very distinct family of the Cyprinodontidae--inhabitants of the
fresh waters of foreign lands--the sexes sometimes differ much in various
characters.  In the male of the Mollienesia petenensis (16.  With respect
to this and the following species I am indebted to Dr. Gunther for
information:  see also his paper on the 'Fishes of Central America,' in
'Transact. Zoological Soc.' vol. vi. 1868, p. 485.), the dorsal fin is
greatly developed and is marked with a row of large, round, ocellated,
bright-coloured spots; whilst the same fin in the female is smaller, of a
different shape, and marked only with irregularly curved brown spots.  In
the male the basal margin of the anal fin is also a little produced and
dark coloured.  In the male of an allied form, the Xiphophorus Hellerii
(Fig. 30), the inferior margin of the caudal fin is developed into a long
filament, which, as I hear from Dr. Gunther, is striped with bright
colours.  This filament does not contain any muscles, and apparently cannot
be of any direct use to the fish.  As in the case of the Callionymus, the
males whilst young resemble the adult females in colour and structure.
Sexual differences such as these may be strictly compared with those which
are so frequent with gallinaceous birds.  (17.  Dr. Gunther makes this
remark; 'Catalogue of Fishes in the British Museum,' vol. iii. 1861, p.
141.)

[Fig.31.  Plecostomus barbatus.
Upper figure, head of male;
lower figure, female.]

In a siluroid fish, inhabiting the fresh waters of South America, the
Plecostomus barbatus (18.  See Dr. Gunther on this genus, in 'Proceedings
of the Zoological Society,' 1868, p. 232.) (Fig. 31), the male has its
mouth and inter-operculum fringed with a beard of stiff hairs, of which the
female shows hardly a trace.  These hairs are of the nature of scales.  In
another species of the same genus, soft flexible tentacles project from the
front part of the head of the male, which are absent in the female.  These
tentacles are prolongations of the true skin, and therefore are not
homologous with the stiff hairs of the former species; but it can hardly be
doubted that both serve the same purpose.  What this purpose may be, it is
difficult to conjecture; ornament does not here seem probable, but we can
hardly suppose that stiff hairs and flexible filaments can be useful in any
ordinary way to the males alone.  In that strange monster, the Chimaera
monstrosa, the male has a hook-shaped bone on the top of the head, directed
forwards, with its end rounded and covered with sharp spines; in the female
"this crown is altogether absent," but what its use may be to the male is
utterly unknown.  (19.  F. Buckland, in 'Land and Water,' July 1868, p.
377, with a figure.  Many other cases could be added of structures peculiar
to the male, of which the uses are not known.)

The structures as yet referred to are permanent in the male after he has
arrived at maturity; but with some Blennies, and in another allied genus
(20.  Dr. Gunther, 'Catalogue of Fishes,' vol. iii. pp. 221 and 240.), a
crest is developed on the head of the male only during the breeding-season,
and the body at the same time becomes more brightly-coloured.  There can be
little doubt that this crest serves as a temporary sexual ornament, for the
female does not exhibit a trace of it.  In other species of the same genus
both sexes possess a crest, and in at least one species neither sex is thus
provided.  In many of the Chromidae, for instance in Geophagus and
especially in Cichla, the males, as I hear from Professor Agassiz (21.  See
also 'A Journey in Brazil,' by Prof. and Mrs. Agassiz, 1868, p. 220.), have
a conspicuous protuberance on the forehead, which is wholly wanting in the
females and in the young males.  Professor Agassiz adds, "I have often
observed these fishes at the time of spawning when the protuberance is
largest, and at other seasons when it is totally wanting, and the two sexes
shew no difference whatever in the outline of the profile of the head.  I
never could ascertain that it subserves any special function, and the
Indians on the Amazon know nothing about its use."  These protuberances
resemble, in their periodical appearance, the fleshy carbuncles on the
heads of certain birds; but whether they serve as ornaments must remain at
present doubtful.

I hear from Professor Agassiz and Dr. Gunther, that the males of those
fishes, which differ permanently in colour from the females, often become
more brilliant during the breeding-season.  This is likewise the case with
a multitude of fishes, the sexes of which are identical in colour at all
other seasons of the year.  The tench, roach, and perch may be given as
instances.  The male salmon at this season is "marked on the cheeks with
orange-coloured stripes, which give it the appearance of a Labrus, and the
body partakes of a golden orange tinge.  The females are dark in colour,
and are commonly called black-fish."  (22.  Yarrell, 'History of British
Fishes,' vol. ii. 1836, pp. 10, 12, 35.)  An analogous and even greater
change takes place with the Salmo eriox or bull trout; the males of the
char (S. umbla) are likewise at this season rather brighter in colour than
the females.  (23.  W. Thompson, in 'Annals and Magazine of Natural
History,' vol. vi. 1841, p. 440.)  The colours of the pike (Esox
reticulatus) of the United States, especially of the male, become, during
the breeding-season, exceedingly intense, brilliant, and iridescent. (24.
'The American Agriculturalist,' 1868, p. 100.)  Another striking instance
out of many is afforded by the male stickleback (Gasterosteus leiurus),
which is described by Mr. Warington (25.  'Annals and Mag. of Nat. Hist.'
Oct. 1852.), as being then "beautiful beyond description."  The back and
eyes of the female are simply brown, and the belly white.  The eyes of the
male, on the other hand, are "of the most splendid green, having a metallic
lustre like the green feathers of some humming-birds.  The throat and belly
are of a bright crimson, the back of an ashy-green, and the whole fish
appears as though it were somewhat translucent and glowed with an internal
incandescence."  After the breeding season these colours all change, the
throat and belly become of a paler red, the back more green, and the
glowing tints subside.

With respect to the courtship of fishes, other cases have been observed
since the first edition of this book appeared, besides that already given
of the stickleback.  Mr. W.S. Kent says that the male of the Labrus mixtus,
which, as we have seen, differs in colour from the female, makes "a deep
hollow in the sand of the tank, and then endeavours in the most persuasive
manner to induce a female of the same species to share it with him,
swimming backwards and forwards between her and the completed nest, and
plainly exhibiting the greatest anxiety for her to follow."  The males of
Cantharus lineatus become, during the breeding-season, of deep leaden-
black; they then retire from the shoal, and excavate a hollow as a nest.
"Each male now mounts vigilant guard over his respective hollow, and
vigorously attacks and drives away any other fish of the same sex.  Towards
his companions of the opposite sex his conduct is far different; many of
the latter are now distended with spawn, and these he endeavours by all the
means in his power to lure singly to his prepared hollow, and there to
deposit the myriad ova with which they are laden, which he then protects
and guards with the greatest care."  (26.  'Nature,' May 1873, p. 25.)

A more striking case of courtship, as well as of display, by the males of a
Chinese Macropus has been given by M. Carbonnier, who carefully observed
these fishes under confinement.  (27.  'Bulletin de la Societe d'Acclimat.'
Paris, July 1869, and Jan. 1870.)  The males are most beautifully coloured,
more so than the females.  During the breeding-season they contend for the
possession of the females; and, in the act of courtship, expand their fins,
which are spotted and ornamented with brightly coloured rays, in the same
manner, according to M. Carbonnier, as the peacock.  They then also bound
about the females with much vivacity, and appear by "l'etalage de leurs
vives couleurs chercher a attirer l'attention des femelles, lesquelles ne
paraissaient indifferentes a ce manege, elles nageaient avec une molle
lenteur vers les males et semblaient se complaire dans leur voisinage."
After the male has won his bride, he makes a little disc of froth by
blowing air and mucus out of his mouth.  He then collects the fertilised
ova, dropped by the female, in his mouth; and this caused M. Carbonnier
much alarm, as he thought that they were going to be devoured.  But the
male soon deposits them in the disc of froth, afterwards guarding them,
repairing the froth, and taking care of the young when hatched.  I mention
these particulars because, as we shall presently see, there are fishes, the
males of which hatch their eggs in their mouths; and those who do not
believe in the principle of gradual evolution might ask how could such a
habit have originated; but the difficulty is much diminished when we know
that there are fishes which thus collect and carry the eggs; for if delayed
by any cause in depositing them, the habit of hatching them in their mouths
might have been acquired.

To return to our more immediate subject.  The case stands thus:  female
fishes, as far as I can learn, never willingly spawn except in the presence
of the males; and the males never fertilise the ova except in the presence
of the females.  The males fight for the possession of the females.  In
many species, the males whilst young resemble the females in colour; but
when adult become much more brilliant, and retain their colours throughout
life.  In other species the males become brighter than the females and
otherwise more highly ornamented, only during the season of love.  The
males sedulously court the females, and in one case, as we have seen, take
pains in displaying their beauty before them.  Can it be believed that they
would thus act to no purpose during their courtship?  And this would be the
case, unless the females exert some choice and select those males which
please or excite them most.  If the female exerts such choice, all the
above facts on the ornamentation of the males become at once intelligible
by the aid of sexual selection.

We have next to inquire whether this view of the bright colours of certain
male fishes having been acquired through sexual selection can, through the
law of the equal transmission of characters to both sexes, be extended to
those groups in which the males and females are brilliant in the same, or
nearly the same degree and manner.  In such a genus as Labrus, which
includes some of the most splendid fishes in the world--for instance, the
Peacock Labrus (L. pavo), described (28.  Bory Saint Vincent, in 'Dict.
Class. d'Hist. Nat.' tom. ix. 1826, p. 151.), with pardonable exaggeration,
as formed of polished scales of gold, encrusting lapis-lazuli, rubies,
sapphires, emeralds, and amethysts--we may, with much probability, accept
this belief; for we have seen that the sexes in at least one species of the
genus differ greatly in colour.  With some fishes, as with many of the
lowest animals, splendid colours may be the direct result of the nature of
their tissues and of the surrounding conditions, without the aid of
selection of any kind.  The gold-fish (Cyprinus auratus), judging from the
analogy of the golden variety of the common carp, is perhaps a case in
point, as it may owe its splendid colours to a single abrupt variation, due
to the conditions to which this fish has been subjected under confinement.
It is, however, more probable that these colours have been intensified
through artificial selection, as this species has been carefully bred in
China from a remote period.  (29.  Owing to some remarks on this subject,
made in my work 'On the Variation of Animals under Domestication,' Mr. W.F.
Mayers ('Chinese Notes and Queries,' Aug. 1868, p. 123) has searched the
ancient Chinese encyclopedias.  He finds that gold-fish were first reared
in confinement during the Sung Dynasty, which commenced A.D. 960.  In the
year 1129 these fishes abounded.  In another place it is said that since
the year 1548 there has been "produced at Hangchow a variety called the
fire-fish, from its intensely red colour.  It is universally admired, and
there is not a household where it is not cultivated, IN RIVALRY AS TO ITS
COLOUR, and as a source of profit.")  Under natural conditions it does not
seem probable that beings so highly organised as fishes, and which live
under such complex relations, should become brilliantly coloured without
suffering some evil or receiving some benefit from so great a change, and
consequently without the intervention of natural selection.

What, then, are we to conclude in regard to the many fishes, both sexes of
which are splendidly coloured?  Mr. Wallace (30.  'Westminster Review,'
July 1867, p. 7.) believes that the species which frequent reefs, where
corals and other brightly-coloured organisms abound, are brightly coloured
in order to escape detection by their enemies; but according to my
recollection they were thus rendered highly conspicuous.  In the fresh-
waters of the tropics there are no brilliantly-coloured corals or other
organisms for the fishes to resemble; yet many species in the Amazons are
beautifully coloured, and many of the carnivorous Cyprinidae in India are
ornamented with "bright longitudinal lines of various tints."  (31.
'Indian Cyprinidae,' by Mr. M'Clelland, 'Asiatic Researches,' vol. xix.
part ii. 1839, p. 230.)  Mr. M'Clelland, in describing these fishes, goes
so far as to suppose that "the peculiar brilliancy of their colours" serves
as "a better mark for king-fishers, terns, and other birds which are
destined to keep the number of these fishes in check"; but at the present
day few naturalists will admit that any animal has been made conspicuous as
an aid to its own destruction.  It is possible that certain fishes may have
been rendered conspicuous in order to warn birds and beasts of prey that
they were unpalatable, as explained when treating of caterpillars; but it
is not, I believe, known that any fish, at least any fresh-water fish, is
rejected from being distasteful to fish-devouring animals.  On the whole,
the most probable view in regard to the fishes, of which both sexes are
brilliantly coloured, is that their colours were acquired by the males as a
sexual ornament, and were transferred equally, or nearly so, to the other
sex.

We have now to consider whether, when the male differs in a marked manner
from the female in colour or in other ornaments, he alone has been
modified, the variations being inherited by his male offspring alone; or
whether the female has been specially modified and rendered inconspicuous
for the sake of protection, such modifications being inherited only by the
females.  It is impossible to doubt that colour has been gained by many
fishes as a protection:  no one can examine the speckled upper surface of a
flounder, and overlook its resemblance to the sandy bed of the sea on which
it lives.  Certain fishes, moreover, can through the action of the nervous
system change their colours in adaptation to surrounding objects, and that
within a short time.  (32.  G. Pouchet, 'L'Institut.' Nov. 1, 1871, p.
134.)  One of the most striking instances ever recorded of an animal being
protected by its colour (as far as it can be judged of in preserved
specimens), as well as by its form, is that given by Dr. Gunther (33.
'Proc. Zoolog. Soc.' 1865, p. 327, pl. xiv. and xv.) of a pipe-fish, which,
with its reddish streaming filaments, is hardly distinguishable from the
sea-weed to which it clings with its prehensile tail.  But the question now
under consideration is whether the females alone have been modified for
this object.  We can see that one sex will not be modified through natural
selection for the sake of protection more than the other, supposing both to
vary, unless one sex is exposed for a longer period to danger, or has less
power of escaping from such danger than the other; and it does not appear
that with fishes the sexes differ in these respects.  As far as there is
any difference, the males, from being generally smaller and from wandering
more about, are exposed to greater danger than the females; and yet, when
the sexes differ, the males are almost always the more conspicuously
coloured.  The ova are fertilised immediately after being deposited; and
when this process lasts for several days, as in the case of the salmon (34.
Yarrell, 'British Fishes,' vol. ii. p. 11.), the female, during the whole
time, is attended by the male.  After the ova are fertilised they are, in
most cases, left unprotected by both parents, so that the males and
females, as far as oviposition is concerned, are equally exposed to danger,
and both are equally important for the production of fertile ova;
consequently the more or less brightly-coloured individuals of either sex
would be equally liable to be destroyed or preserved, and both would have
an equal influence on the colours of their offspring.

Certain fishes, belonging to several families, make nests, and some of them
take care of their young when hatched.  Both sexes of the bright coloured
Crenilabrus massa and melops work together in building their nests with
sea-weed, shells, etc.  (35.  According to the observations of M. Gerbe;
see Gunther's 'Record of Zoolog. Literature,' 1865, p. 194.)  But the males
of certain fishes do all the work, and afterwards take exclusive charge of
the young.  This is the case with the dull-coloured gobies (36.  Cuvier,
'Regne Animal,' vol. ii. 1829, p. 242.), in which the sexes are not known
to differ in colour, and likewise with the sticklebacks (Gasterosteus), in
which the males become brilliantly coloured during the spawning season.
The male of the smooth-tailed stickleback (G. leiurus) performs the duties
of a nurse with exemplary care and vigilance during a long time, and is
continually employed in gently leading back the young to the nest, when
they stray too far.  He courageously drives away all enemies including the
females of his own species.  It would indeed be no small relief to the
male, if the female, after depositing her eggs, were immediately devoured
by some enemy, for he is forced incessantly to drive her from the nest.
(37.  See Mr. Warington's most interesting description of the habits of the
Gasterosteus leiurus in 'Annals and Magazine of Nat. History,' November
1855.)

The males of certain other fishes inhabiting South America and Ceylon,
belonging to two distinct Orders, have the extraordinary habit of hatching
within their mouths, or branchial cavities, the eggs laid by the females.
(38.  Prof. Wyman, in 'Proc. Boston Soc. of Nat. Hist.' Sept. 15, 1857.
Also Prof. Turner, in 'Journal of Anatomy and Physiology,' Nov. 1, 1866, p.
78.  Dr. Gunther has likewise described other cases.)  I am informed by
Professor Agassiz that the males of the Amazonian species which follow this
habit, "not only are generally brighter than the females, but the
difference is greater at the spawning-season than at any other time."  The
species of Geophagus act in the same manner; and in this genus, a
conspicuous protuberance becomes developed on the forehead of the males
during the breeding-season.  With the various species of Chromids, as
Professor Agassiz likewise informs me, sexual differences in colour may be
observed, "whether they lay their eggs in the water among aquatic plants,
or deposit them in holes, leaving them to come out without further care, or
build shallow nests in the river mud, over which they sit, as our Pomotis
does.  It ought also to be observed that these sitters are among the
brightest species in their respective families; for instance, Hygrogonus is
bright green, with large black ocelli, encircled with the most brilliant
red."  Whether with all the species of Chromids it is the male alone which
sits on the eggs is not known.  It is, however, manifest that the fact of
the eggs being protected or unprotected by the parents, has had little or
no influence on the differences in colour between the sexes.  It is further
manifest, in all the cases in which the males take exclusive charge of the
nests and young, that the destruction of the brighter-coloured males would
be far more influential on the character of the race, than the destruction
of the brighter-coloured females; for the death of the male during the
period of incubation or nursing would entail the death of the young, so
that they could not inherit his peculiarities; yet, in many of these very
cases the males are more conspicuously coloured than the females.

In most of the Lophobranchii (Pipe-fish, Hippocampi, etc.) the males have
either marsupial sacks or hemispherical depressions on the abdomen, in
which the ova laid by the female are hatched.  The males also shew great
attachment to their young.  (39.  Yarrell, 'History of British Fishes,'
vol. ii. 1836, pp. 329, 338.)  The sexes do not commonly differ much in
colour; but Dr. Gunther believes that the male Hippocampi are rather
brighter than the females.  The genus Solenostoma, however, offers a
curious exceptional case (40.  Dr. Gunther, since publishing an account of
this species in 'The Fishes of Zanzibar,' by Col. Playfair, 1866, p. 137,
has re-examined the specimens, and has given me the above information.),
for the female is much more vividly-coloured and spotted than the male, and
she alone has a marsupial sack and hatches the eggs; so that the female of
Solenostoma differs from all the other Lophobranchii in this latter
respect, and from almost all other fishes, in being more brightly-coloured
than the male.  It is improbable that this remarkable double inversion of
character in the female should be an accidental coincidence.  As the males
of several fishes, which take exclusive charge of the eggs and young, are
more brightly coloured than the females, and as here the female Solenostoma
takes the same charge and is brighter than the male, it might be argued
that the conspicuous colours of that sex which is the more important of the
two for the welfare of the offspring, must be in some manner protective.
But from the large number of fishes, of which the males are either
permanently or periodically brighter than the females, but whose life is
not at all more important for the welfare of the species than that of the
female, this view can hardly be maintained.  When we treat of birds we
shall meet with analogous cases, where there has been a complete inversion
of the usual attributes of the two sexes, and we shall then give what
appears to be the probable explanation, namely, that the males have
selected the more attractive females, instead of the latter having
selected, in accordance with the usual rule throughout the animal kingdom,
the more attractive males.

On the whole we may conclude, that with most fishes, in which the sexes
differ in colour or in other ornamental characters, the males originally
varied, with their variations transmitted to the same sex, and accumulated
through sexual selection by attracting or exciting the females.  In many
cases, however, such characters have been transferred, either partially or
completely, to the females.  In other cases, again, both sexes have been
coloured alike for the sake of protection; but in no instance does it
appear that the female alone has had her colours or other characters
specially modified for this latter purpose.

The last point which need be noticed is that fishes are known to make
various noises, some of which are described as being musical.  Dr. Dufosse,
who has especially attended to this subject, says that the sounds are
voluntarily produced in several ways by different fishes:  by the friction
of the pharyngeal bones--by the vibration of certain muscles attached to
the swim bladder, which serves as a resounding board--and by the vibration
of the intrinsic muscles of the swim bladder.  By this latter means the
Trigla produces pure and long-drawn sounds which range over nearly an
octave.  But the most interesting case for us is that of two species of
Ophidium, in which the males alone are provided with a sound-producing
apparatus, consisting of small movable bones, with proper muscles, in
connection with the swim bladder.  (41.  'Comptes-Rendus,' tom. xlvi. 1858,
p. 353; tom. xlvii. 1858, p. 916; tom. liv. 1862, p. 393.  The noise made
by the Umbrinas (Sciaena aquila), is said by some authors to be more like
that of a flute or organ, than drumming:  Dr. Zouteveen, in the Dutch
translation of this work (vol. ii. p. 36), gives some further particulars
on the sounds made by fishes.)  The drumming of the Umbrinas in the
European seas is said to be audible from a depth of twenty fathoms; and the
fishermen of Rochelle assert "that the males alone make the noise during
the spawning-time; and that it is possible by imitating it, to take them
without bait."  (42.  The Rev. C. Kingsley, in 'Nature,' May 1870, p. 40.)
From this statement, and more especially from the case of Ophidium, it is
almost certain that in this, the lowest class of the Vertebrata, as with so
many insects and spiders, sound-producing instruments have, at least in
some cases, been developed through sexual selection, as a means for
bringing the sexes together.

AMPHIBIANS.

URODELA.

[Fig. 32.  Triton cristatus (half natural size, from Bell's 'British
Reptiles').
Upper figure, male during the breeding season;
lower figure, female.]

I will begin with the tailed amphibians.  The sexes of salamanders or newts
often differ much both in colour and structure.  In some species prehensile
claws are developed on the fore-legs of the males during the breeding-
season:  and at this season in the male Triton palmipes the hind-feet are
provided with a swimming-web, which is almost completely absorbed during
the winter; so that their feet then resemble those of the female.  (43.
Bell, 'History of British Reptiles,' 2nd ed., 1849, pp. 156-159.)  This
structure no doubt aids the male in his eager search and pursuit of the
female.  Whilst courting her he rapidly vibrates the end of his tail.  With
our common newts (Triton punctatus and cristatus) a deep, much indented
crest is developed along the back and tail of the male during the breeding-
season, which disappears during the winter.  Mr. St. George Mivart informs
me that it is not furnished with muscles, and therefore cannot be used for
locomotion.  As during the season of courtship it becomes edged with bright
colours, there can hardly be a doubt that it is a masculine ornament.  In
many species the body presents strongly contrasted, though lurid tints, and
these become more vivid during the breeding-season.  The male, for
instance, of our common little newt (Triton punctatus) is "brownish-grey
above, passing into yellow beneath, which in the spring becomes a rich
bright orange, marked everywhere with round dark spots."  The edge of the
crest also is then tipped with bright red or violet.  The female is usually
of a yellowish-brown colour with scattered brown dots, and the lower
surface is often quite plain.  (44.  Bell, 'History of British Reptiles,'
2nd ed., 1849, pp. 146, 151.)  The young are obscurely tinted.  The ova are
fertilised during the act of deposition, and are not subsequently tended by
either parent.  We may therefore conclude that the males have acquired
their strongly-marked colours and ornamental appendages through sexual
selection; these being transmitted either to the male offspring alone, or
to both sexes.

ANURA OR BATRACHIA.

With many frogs and toads the colours evidently serve as a protection, such
as the bright green tints of tree frogs and the obscure mottled shades of
many terrestrial species.  The most conspicuously-coloured toad which I
ever saw, the Phryniscus nigricans (45.  'Zoology of the Voyage of the
"Beagle,"' 1843.  Bell, ibid. p. 49.), had the whole upper surface of the
body as black as ink, with the soles of the feet and parts of the abdomen
spotted with the brightest vermilion.  It crawled about the bare sandy or
open grassy plains of La Plata under a scorching sun, and could not fail to
catch the eye of every passing creature.  These colours are probably
beneficial by making this animal known to all birds of prey as a nauseous
mouthful.

In Nicaragua there is a little frog "dressed in a bright livery of red and
blue" which does not conceal itself like most other species, but hops about
during the daytime, and Mr. Belt says (46.  'The Naturalist in Nicaragua,'
1874, p. 321.) that as soon as he saw its happy sense of security, he felt
sure that it was uneatable.  After several trials he succeeded in tempting
a young duck to snatch up a young one, but it was instantly rejected; and
the duck "went about jerking its head, as if trying to throw off some
unpleasant taste."

With respect to sexual differences of colour, Dr. Gunther does not know of
any striking instance either with frogs or toads; yet he can often
distinguish the male from the female by the tints of the former being a
little more intense.  Nor does he know of any striking difference in
external structure between the sexes, excepting the prominences which
become developed during the breeding-season on the front legs of the male,
by which he is enabled to hold the female.  (47.  The male alone of the
Bufo sikimmensis (Dr. Anderson, 'Proc. Zoolog. Soc.' 1871, p. 204) has two
plate-like callosities on the thorax and certain rugosities on the fingers,
which perhaps subserve the same end as the above-mentioned prominences.)
It is surprising that these animals have not acquired more strongly-marked
sexual characters; for though cold-blooded their passions are strong.  Dr.
Gunther informs me that he has several times found an unfortunate female
toad dead and smothered from having been so closely embraced by three or
four males.  Frogs have been observed by Professor Hoffman in Giessen
fighting all day long during the breeding-season, and with so much violence
that one had its body ripped open.

Frogs and toads offer one interesting sexual difference, namely, in the
musical powers possessed by the males; but to speak of music, when applied
to the discordant and overwhelming sounds emitted by male bull-frogs and
some other species, seems, according to our taste, a singularly
inappropriate expression.  Nevertheless, certain frogs sing in a decidedly
pleasing manner.  Near Rio Janeiro I used often to sit in the evening to
listen to a number of little Hylae, perched on blades of grass close to the
water, which sent forth sweet chirping notes in harmony.  The various
sounds are emitted chiefly by the males during the breeding-season, as in
the case of the croaking of our common frog.  (48.  Bell, 'History British
Reptiles,' 1849, p. 93.)  In accordance with this fact the vocal organs of
the males are more highly-developed than those of the females.  In some
genera the males alone are provided with sacs which open into the larynx.
(49.  J. Bishop, in 'Todd's Cyclopaedia of Anatomy and Physiology,' vol.
iv. p. 1503.)  For instance, in the edible frog (Rana esculenta) "the sacs
are peculiar to the males, and become, when filled with air in the act of
croaking, large globular bladders, standing out one on each side of the
head, near the corners of the mouth."  The croak of the male is thus
rendered exceedingly powerful; whilst that of the female is only a slight
groaning noise.  (50.  Bell, ibid. pp. 112-114.)  In the several genera of
the family the vocal organs differ considerably in structure, and their
development in all cases may be attributed to sexual selection.

REPTILES.

CHELONIA.

Tortoises and turtles do not offer well-marked sexual differences.  In some
species, the tail of the male is longer than that of the female.  In some,
the plastron or lower surface of the shell of the male is slightly concave
in relation to the back of the female.  The male of the mud-turtle of the
United States (Chrysemys picta) has claws on its front feet twice as long
as those of the female; and these are used when the sexes unite.  (51.  Mr.
C.J. Maynard, 'The American Naturalist,' Dec. 1869, p. 555.)  With the huge
tortoise of the Galapagos Islands (Testudo nigra) the males are said to
grow to a larger size than the females:  during the pairing-season, and at
no other time, the male utters a hoarse bellowing noise, which can be heard
at the distance of more than a hundred yards; the female, on the other
hand, never uses her voice.  (52.  See my 'Journal of Researches during the
Voyage of the "Beagle,"' 1845, p. 384.)

With the Testudo elegans of India, it is said "that the combats of the
males may be heard at some distance, from the noise they produce in butting
against each other."  (53.  Dr. Gunther, 'Reptiles of British India,' 1864,
p. 7.)

CROCODILIA.

The sexes apparently do not differ in colour; nor do I know that the males
fight together, though this is probable, for some kinds make a prodigious
display before the females.  Bartram (54.  'Travels through Carolina,'
etc., 1791, p. 128.) describes the male alligator as striving to win the
female by splashing and roaring in the midst of a lagoon, "swollen to an
extent ready to burst, with its head and tail lifted up, he springs or
twirls round on the surface of the water, like an Indian chief rehearsing
his feats of war."  During the season of love, a musky odour is emitted by
the submaxillary glands of the crocodile, and pervades their haunts.  (55.
Owen, 'Anatomy of Vertebrates,' vol. i. 1866, p. 615.)

OPHIDIA.

Dr. Gunther informs me that the males are always smaller than the females,
and generally have longer and slenderer tails; but he knows of no other
difference in external structure.  In regard to colour, be can almost
always distinguish the male from the female, by his more strongly-
pronounced tints; thus the black zigzag band on the back of the male
English viper is more distinctly defined than in the female.  The
difference is much plainer in the rattle-snakes of N. America, the male of
which, as the keeper in the Zoological Gardens shewed me, can at once be
distinguished from the female by having more lurid yellow about its whole
body.  In S. Africa the Bucephalus capensis presents an analogous
difference, for the female "is never so fully variegated with yellow on the
sides as the male."  (56.  Sir Andrew Smith, 'Zoology of S. Africa:
Reptilia,' 1849, pl. x.)  The male of the Indian Dipsas cynodon, on the
other hand, is blackish-brown, with the belly partly black, whilst the
female is reddish or yellowish-olive, with the belly either uniform
yellowish or marbled with black.  In the Tragops dispar of the same country
the male is bright green, and the female bronze-coloured.  (57.  Dr. A.
Gunther, 'Reptiles of British India,' Ray Soc., 1864, pp. 304, 308.)  No
doubt the colours of some snakes are protective, as shewn by the green
tints of tree-snakes, and the various mottled shades of the species which
live in sandy places; but it is doubtful whether the colours of many kinds,
for instance of the common English snake and viper, serve to conceal them;
and this is still more doubtful with the many foreign species which are
coloured with extreme elegance.  The colours of certain species are very
different in the adult and young states. (58.  Dr. Stoliczka, 'Journal of
Asiatic Society of Bengal,' vol. xxxix, 1870, pp. 205, 211.)

During the breeding-season the anal scent-glands of snakes are in active
function (59.  Owen, 'Anatomy of Vertebrates,' vol. i. 1866, p. 615.); and
so it is with the same glands in lizards, and as we have seen with the
submaxillary glands of crocodiles.  As the males of most animals search for
the females, these odoriferous glands probably serve to excite or charm the
female, rather than to guide her to the spot where the male may be found.
Male snakes, though appearing so sluggish, are amorous; for many have been
observed crowding round the same female, and even round her dead body.
They are not known to fight together from rivalry.  Their intellectual
powers are higher than might have been anticipated.  In the Zoological
Gardens they soon learn not to strike at the iron bar with which their
cages are cleaned; and Dr. Keen of Philadelphia informs me that some snakes
which he kept learned after four or five times to avoid a noose, with which
they were at first easily caught.  An excellent observer in Ceylon, Mr. E.
Layard, saw (60.  'Rambles in Ceylon,' in 'Annals and Magazine of Natural
History,' 2nd series, vol. ix. 1852, p. 333.) a cobra thrust its head
through a narrow hole and swallow a toad.  "With this encumbrance he could
not withdraw himself; finding this, he reluctantly disgorged the precious
morsel, which began to move off; this was too much for snake philosophy to
bear, and the toad was again seized, and again was the snake, after violent
efforts to escape, compelled to part with its prey.  This time, however, a
lesson had been learnt, and the toad was seized by one leg, withdrawn, and
then swallowed in triumph."

The keeper in the Zoological Gardens is positive that certain snakes, for
instance Crotalus and Python, distinguish him from all other persons.
Cobras kept together in the same cage apparently feel some attachment
towards each other.  (61.  Dr. Gunther, 'Reptiles of British India,' 1864,
p. 340.)

It does not, however, follow because snakes have some reasoning power,
strong passions and mutual affection, that they should likewise be endowed
with sufficient taste to admire brilliant colours in their partners, so as
to lead to the adornment of the species through sexual selection.
Nevertheless, it is difficult to account in any other manner for the
extreme beauty of certain species; for instance, of the coral-snakes of S.
America, which are of a rich red with black and yellow transverse bands.  I
well remember how much surprise I felt at the beauty of the first coral-
snake which I saw gliding across a path in Brazil.  Snakes coloured in this
peculiar manner, as Mr. Wallace states on the authority of Dr. Gunther (62.
'Westminster Review,' July 1st, 1867, p. 32.), are found nowhere else in
the world except in S. America, and here no less than four genera occur.
One of these, Elaps, is venomous; a second and widely-distinct genus is
doubtfully venomous, and the two others are quite harmless.  The species
belonging to these distinct genera inhabit the same districts, and are so
like each other that no one "but a naturalist would distinguish the
harmless from the poisonous kinds."  Hence, as Mr. Wallace believes, the
innocuous kinds have probably acquired their colours as a protection, on
the principle of imitation; for they would naturally be thought dangerous
by their enemies.  The cause, however, of the bright colours of the
venomous Elaps remains to be explained, and this may perhaps be sexual
selection.

Snakes produce other sounds besides hissing.  The deadly Echis carinata has
on its sides some oblique rows of scales of a peculiar structure with
serrated edges; and when this snake is excited these scales are rubbed
against each other, which produces "a curious prolonged, almost hissing
sound."  (63.  Dr. Anderson, 'Proc. Zoolog. Soc.' 1871, p. 196.)  With
respect to the rattling of the rattle-snake, we have at last some definite
information:  for Professor Aughey states (64.  The 'American Naturalist,'
1873, p. 85.), that on two occasions, being himself unseen, he watched from
a little distance a rattle-snake coiled up with head erect, which continued
to rattle at short intervals for half an hour:  and at last he saw another
snake approach, and when they met they paired.  Hence he is satisfied that
one of the uses of the rattle is to bring the sexes together.
Unfortunately he did not ascertain whether it was the male or the female
which remained stationary and called for the other.  But it by no means
follows from the above fact that the rattle may not be of use to these
snakes in other ways, as a warning to animals which would otherwise attack
them.  Nor can I quite disbelieve the several accounts which have appeared
of their thus paralysing their prey with fear.  Some other snakes also make
a distinct noise by rapidly vibrating their tails against the surrounding
stalks of plants; and I have myself heard this in the case of a
Trigonocephalus in S. America.

LACERTILIA.

The males of some, probably of many kinds of lizards, fight together from
rivalry.  Thus the arboreal Anolis cristatellus of S. America is extremely
pugnacious:  "During the spring and early part of the summer, two adult
males rarely meet without a contest.  On first seeing one another, they nod
their heads up and down three or four times, and at the same time expanding
the frill or pouch beneath the throat; their eyes glisten with rage, and
after waving their tails from side to side for a few seconds, as if to
gather energy, they dart at each other furiously, rolling over and over,
and holding firmly with their teeth.  The conflict generally ends in one of
the combatants losing his tail, which is often devoured by the victor."
The male of this species is considerably larger than the female (65.  Mr.
N.L. Austen kept these animals alive for a considerable time; see 'Land and
Water,' July 1867, p. 9.); and this, as far as Dr. Gunther has been able to
ascertain, is the general rule with lizards of all kinds.  The male alone
of the Cyrtodactylus rubidus of the Andaman Islands possesses pre-anal
pores; and these pores, judging from analogy, probably serve to emit an
odour. (66.  Stoliczka, 'Journal of the Asiatic Society of Bengal,' vol.
xxxiv. 1870, p. 166.)

[Fig.33.  Sitana minor.
Male with the gular pouch expanded (from Gunther's 'Reptiles of India')']

The sexes often differ greatly in various external characters.  The male of
the above-mentioned Anolis is furnished with a crest which runs along the
back and tail, and can be erected at pleasure; but of this crest the female
does not exhibit a trace.  In the Indian Cophotis ceylanica, the female has
a dorsal crest, though much less developed than in the male; and so it is,
as Dr. Gunther informs me, with the females of many Iguanas, Chameleons,
and other lizards.  In some species, however, the crest is equally
developed in both sexes, as in the Iguana tuberculata.  In the genus
Sitana, the males alone are furnished with a large throat pouch (Fig. 33),
which can be folded up like a fan, and is coloured blue, black, and red;
but these splendid colours are exhibited only during the pairing-season.
The female does not possess even a rudiment of this appendage.  In the
Anolis cristatellus, according to Mr. Austen, the throat pouch, which is
bright red marbled with yellow, is present in the female, though in a
rudimental condition.  Again, in certain other lizards, both sexes are
equally well provided with throat pouches.  Here we see with species
belonging to the same group, as in so many previous cases, the same
character either confined to the males, or more largely developed in them
than in the females, or again equally developed in both sexes.  The little
lizards of the genus Draco, which glide through the air on their rib-
supported parachutes, and which in the beauty of their colours baffle
description, are furnished with skinny appendages to the throat "like the
wattles of gallinaceous birds."  These become erected when the animal is
excited.  They occur in both sexes, but are best developed when the male
arrives at maturity, at which age the middle appendage is sometimes twice
as long as the head.  Most of the species likewise have a low crest running
along the neck; and this is much more developed in the full-grown males
than in the females or young males.  (67.  All the foregoing statements and
quotations, in regard to Cophotis, Sitana and Draco, as well as the
following facts in regard to Ceratophora and Chamaeleon, are from Dr.
Gunther himself, or from his magnificent work on the 'Reptiles of British
India,' Ray Soc., 1864, pp. 122, 130, 135.)

A Chinese species is said to live in pairs during the spring; "and if one
is caught, the other falls from the tree to the ground, and allows itself
to be captured with impunity"--I presume from despair.  (68.  Mr. Swinhoe,
'Proc. Zoolog. Soc.' 1870, p. 240.)

[Fig. 34.  Ceratophora Stoddartii.
Upper figure;
lower figure, female.]

There are other and much more remarkable differences between the sexes of
certain lizards.  The male of Ceratophora aspera bears on the extremity of
his snout an appendage half as long as the head.  It is cylindrical,
covered with scales, flexible, and apparently capable of erection:  in the
female it is quite rudimental.  In a second species of the same genus a
terminal scale forms a minute horn on the summit of the flexible appendage;
and in a third species (C. Stoddartii, fig. 34) the whole appendage is
converted into a horn, which is usually of a white colour, but assumes a
purplish tint when the animal is excited.  In the adult male of this latter
species the horn is half an inch in length, but it is of quite minute size
in the female and in the young.  These appendages, as Dr. Gunther has
remarked to me, may be compared with the combs of gallinaceous birds, and
apparently serve as ornaments.

[Fig. 35.  Chamaeleo bifurcus.
Upper figure, male;
lower figure, female.

Fig. 36.  Chamaeleo Owenii.
Upper figure, male;
lower figure, female.]

In the genus Chamaeleon we come to the acme of difference between the
sexes.  The upper part of the skull of the male C. bifurcus (Fig. 35), an
inhabitant of Madagascar, is produced into two great, solid, bony
projections, covered with scales like the rest of the head; and of this
wonderful modification of structure the female exhibits only a rudiment.
Again, in Chamaeleo Owenii (Fig. 36), from the West Coast of Africa, the
male bears on his snout and forehead three curious horns, of which the
female has not a trace.  These horns consist of an excrescence of bone
covered with a smooth sheath, forming part of the general integuments of
the body, so that they are identical in structure with those of a bull,
goat, or other sheath-horned ruminant.  Although the three horns differ so
much in appearance from the two great prolongations of the skull in C.
bifurcus, we can hardly doubt that they serve the same general purpose in
the economy of these two animals.  The first conjecture, which will occur
to every one, is that they are used by the males for fighting together; and
as these animals are very quarrelsome (69.  Dr. Buchholz, 'Monatsbericht K.
Preuss. Akad.' Jan. 1874, p. 78.), this is probably a correct view.  Mr.
T.W. Wood also informs me that he once watched two individuals of C.
pumilus fighting violently on the branch of a tree; they flung their heads
about and tried to bite each other; they then rested for a time and
afterwards continued their battle.

With many lizards the sexes differ slightly in colour, the tints and
stripes of the males being brighter and more distinctly defined than in the
females.  This, for instance, is the case with the above Cophotis and with
the Acanthodactylus capensis of S. Africa.  In a Cordylus of the latter
country, the male is either much redder or greener than the female.  In the
Indian Calotes nigrilabris there is a still greater difference; the lips
also of the male are black, whilst those of the female are green.  In our
common little viviparous lizard (Zootoca vivipara) "the under side of the
body and base of the tail in the male are bright orange, spotted with
black; in the female these parts are pale-greyish-green without spots."
(70.  Bell, 'History of British Reptiles,' 2nd ed., 1849, p. 40.)  We have
seen that the males alone of Sitana possess a throat-pouch; and this is
splendidly tinted with blue, black, and red.  In the Proctotretus tenuis of
Chile the male alone is marked with spots of blue, green, and coppery-red.
(71.  For Proctotretus, see 'Zoology of the Voyage of the "Beagle";
Reptiles,' by Mr. Bell, p. 8.  For the Lizards of S. Africa, see 'Zoology
of S. Africa:  Reptiles,' by Sir Andrew Smith, pl. 25 and 39.  For the
Indian Calotes, see 'Reptiles of British India,' by Dr. Gunther, p. 143.)
In many cases the males retain the same colours throughout the year, but in
others they become much brighter during the breeding-season; I may give as
an additional instance the Calotes maria, which at this season has a bright
red head, the rest of the body being green.  (72.  Gunther in 'Proceedings,
Zoological Society,' 1870, p. 778, with a coloured figure.)

Both sexes of many species are beautifully coloured exactly alike; and
there is no reason to suppose that such colours are protective.  No doubt
with the bright green kinds which live in the midst of vegetation, this
colour serves to conceal them; and in N. Patagonia I saw a lizard
(Proctotretus multimaculatus) which, when frightened, flattened its body,
closed its eyes, and then from its mottled tints was hardly distinguishable
from the surrounding sand.  But the bright colours with which so many
lizards are ornamented, as well as their various curious appendages, were
probably acquired by the males as an attraction, and then transmitted
either to their male offspring alone, or to both sexes.  Sexual selection,
indeed, seems to have played almost as important a part with reptiles as
with birds; and the less conspicuous colours of the females in comparison
with the males cannot be accounted for, as Mr. Wallace believes to be the
case with birds, by the greater exposure of the females to danger during
incubation.


CHAPTER XIII.

SECONDARY SEXUAL CHARACTERS OF BIRDS.

Sexual differences--Law of battle--Special weapons--Vocal organs--
Instrumental music--Love-antics and dances--Decorations, permanent and
seasonal--Double and single annual moults--Display of ornaments by the
males.

Secondary sexual characters are more diversified and conspicuous in birds,
though not perhaps entailing more important changes of structure, than in
any other class of animals.  I shall, therefore, treat the subject at
considerable length.  Male birds sometimes, though rarely, possess special
weapons for fighting with each other.  They charm the female by vocal or
instrumental music of the most varied kinds.  They are ornamented by all
sorts of combs, wattles, protuberances, horns, air-distended sacks, top-
knots, naked shafts, plumes and lengthened feathers gracefully springing
from all parts of the body.  The beak and naked skin about the head, and
the feathers, are often gorgeously coloured.  The males sometimes pay their
court by dancing, or by fantastic antics performed either on the ground or
in the air.  In one instance, at least, the male emits a musky odour, which
we may suppose serves to charm or excite the female; for that excellent
observer, Mr. Ramsay (1.  'Ibis,' vol. iii. (new series), 1867, p. 414.),
says of the Australian musk-duck (Biziura lobata) that "the smell which the
male emits during the summer months is confined to that sex, and in some
individuals is retained throughout the year; I have never, even in the
breeding-season, shot a female which had any smell of musk."  So powerful
is this odour during the pairing-season, that it can be detected long
before the bird can be seen.  (2. Gould, 'Handbook of the Birds of
Australia,' 1865, vol. ii. p. 383.)  On the whole, birds appear to be the
most aesthetic of all animals, excepting of course man, and they have
nearly the same taste for the beautiful as we have.  This is shewn by our
enjoyment of the singing of birds, and by our women, both civilised and
savage, decking their heads with borrowed plumes, and using gems which are
hardly more brilliantly coloured than the naked skin and wattles of certain
birds.  In man, however, when cultivated, the sense of beauty is manifestly
a far more complex feeling, and is associated with various intellectual
ideas.

Before treating of the sexual characters with which we are here more
particularly concerned, I may just allude to certain differences between
the sexes which apparently depend on differences in their habits of life;
for such cases, though common in the lower, are rare in the higher classes.
Two humming-birds belonging to the genus Eustephanus, which inhabit the
island of Juan Fernandez, were long thought to be specifically distinct,
but are now known, as Mr. Gould informs me, to be the male and female of
the same species, and they differ slightly in the form of the beak.  In
another genus of humming-birds (Grypus), the beak of the male is serrated
along the margin and hooked at the extremity, thus differing much from that
of the female.  In the Neomorpha of New Zealand, there is, as we have seen,
a still wider difference in the form of the beak in relation to the manner
of feeding of the two sexes.  Something of the same kind has been observed
with the goldfinch (Carduelis elegans), for I am assured by Mr. J. Jenner
Weir that the bird-catchers can distinguish the males by their slightly
longer beaks.  The flocks of males are often found feeding on the seeds of
the teazle (Dipsacus), which they can reach with their elongated beaks,
whilst the females more commonly feed on the seeds of the betony or
Scrophularia.  With a slight difference of this kind as a foundation, we
can see how the beaks of the two sexes might be made to differ greatly
through natural selection.  In some of the above cases, however, it is
possible that the beaks of the males may have been first modified in
relation to their contests with other males; and that this afterwards led
to slightly changed habits of life.

LAW OF BATTLE.

Almost all male birds are extremely pugnacious, using their beaks, wings,
and legs for fighting together.  We see this every spring with our robins
and sparrows.  The smallest of all birds, namely the humming-bird, is one
of the most quarrelsome.  Mr. Gosse (3.  Quoted by Mr. Gould, 'Introduction
to the Trochilidae,' 1861, page 29.) describes a battle in which a pair
seized hold of each other's beaks, and whirled round and round, till they
almost fell to the ground; and M. Montes de Oca, in speaking or another
genus of humming-bird, says that two males rarely meet without a fierce
aerial encounter:  when kept in cages "their fighting has mostly ended in
the splitting of the tongue of one of the two, which then surely dies from
being unable to feed."  (4.  Gould, ibid. p. 52.)  With waders, the males
of the common water-hen (Gallinula chloropus) "when pairing, fight
violently for the females:  they stand nearly upright in the water and
strike with their feet."  Two were seen to be thus engaged for half an
hour, until one got hold of the head of the other, which would have been
killed had not the observer interfered; the female all the time looking on
as a quiet spectator.  (5.  W. Thompson, 'Natural History of Ireland:
Birds,' vol. ii. 1850, p. 327.)  Mr. Blyth informs me that the males of an
allied bird (Gallicrex cristatus) are a third larger than the females, and
are so pugnacious during the breeding-season that they are kept by the
natives of Eastern Bengal for the sake of fighting.  Various other birds
are kept in India for the same purpose, for instance, the bulbuls
(Pycnonotus hoemorrhous) which "fight with great spirit."  (6.  Jerdon,
'Birds of India,' 1863, vol. ii. p. 96.)

[Fig. 37.  The Ruff or Machetes pugnax (from Brehm's 'Thierleben').]

The polygamous ruff (Machetes pugnax, Fig. 37) is notorious for his extreme
pugnacity; and in the spring, the males, which are considerably larger than
the females, congregate day after day at a particular spot, where the
females propose to lay their eggs.  The fowlers discover these spots by the
turf being trampled somewhat bare.  Here they fight very much like game-
cocks, seizing each other with their beaks and striking with their wings.
The great ruff of feathers round the neck is then erected, and according to
Col. Montagu "sweeps the ground as a shield to defend the more tender
parts"; and this is the only instance known to me in the case of birds of
any structure serving as a shield.  The ruff of feathers, however, from its
varied and rich colours probably serves in chief part as an ornament.  Like
most pugnacious birds, they seem always ready to fight, and when closely
confined, often kill each other; but Montagu observed that their pugnacity
becomes greater during the spring, when the long feathers on their necks
are fully developed; and at this period the least movement by any one bird
provokes a general battle.  (7.  Macgillivray, 'History of British Birds,'
vol. iv. 1852, pp. 177-181.)  Of the pugnacity of web-footed birds, two
instances will suffice:  in Guiana "bloody fights occur during the
breeding-season between the males of the wild musk-duck (Cairina moschata);
and where these fights have occurred the river is covered for some distance
with feathers."  (8.  Sir R. Schomburgk, in 'Journal of Royal Geographic
Society,' vol. xiii. 1843, p. 31.)  Birds which seem ill-adapted for
fighting engage in fierce conflicts; thus the stronger males of the pelican
drive away the weaker ones, snapping with their huge beaks and giving heavy
blows with their wings.  Male snipe fight together, "tugging and pushing
each other with their bills in the most curious manner imaginable."  Some
few birds are believed never to fight; this is the case, according to
Audubon, with one of the woodpeckers of the United States (Picu sauratus),
although "the hens are followed by even half a dozen of their gay suitors."
(9.  'Ornithological Biography,' vol. i. p. 191.  For pelicans and snipes,
see vol. iii. pp. 138, 477.)

The males of many birds are larger than the females, and this no doubt is
the result of the advantage gained by the larger and stronger males over
their rivals during many generations.  The difference in size between the
two sexes is carried to an extreme point in several Australian species;
thus the male musk-duck (Biziura), and the male Cincloramphus cruralis
(allied to our pipits) are by measurement actually twice as large as their
respective females.  (10.  Gould, 'Handbook of Birds of Australia,' vol. i.
p. 395; vol. ii. p. 383.)  With many other birds the females are larger
than the males; and, as formerly remarked, the explanation often given,
namely, that the females have most of the work in feeding their young, will
not suffice.  In some few cases, as we shall hereafter see, the females
apparently have acquired their greater size and strength for the sake of
conquering other females and obtaining possession of the males.

The males of many gallinaceous birds, especially of the polygamous kinds,
are furnished with special weapons for fighting with their rivals, namely
spurs, which can be used with fearful effect.  It has been recorded by a
trustworthy writer (11.  Mr. Hewitt, in the 'Poultry Book' by Tegetmeier,
1866, p. 137.) that in Derbyshire a kite struck at a game-hen accompanied
by her chickens, when the cock rushed to the rescue, and drove his spur
right through the eye and skull of the aggressor.  The spur was with
difficulty drawn from the skull, and as the kite, though dead, retained his
grasp, the two birds were firmly locked together; but the cock when
disentangled was very little injured.  The invincible courage of the game-
cock is notorious:  a gentleman who long ago witnessed the brutal scene,
told me that a bird had both its legs broken by some accident in the
cockpit, and the owner laid a wager that if the legs could be spliced so
that the bird could stand upright, he would continue fighting.  This was
effected on the spot, and the bird fought with undaunted courage until he
received his death-stroke.  In Ceylon a closely allied, wild species, the
Gallus Stanleyi, is known to fight desperately "in defence of his
seraglio," so that one of the combatants is frequently found dead.  (12.
Layard, 'Annals and Magazine of Natural History,' vol. xiv. 1854, p. 63.)
An Indian partridge (Ortygornis gularis), the male of which is furnished
with strong and sharp spurs, is so quarrelsome "that the scars of former
fights disfigure the breast of almost every bird you kill."  (13.  Jerdon,
'Birds of India,' vol. iii. p. 574.)

The males of almost all gallinaceous birds, even those which are not
furnished with spurs, engage during the breeding-season in fierce
conflicts.  The Capercailzie and Black-cock (Tetrao urogallus and T.
tetrix), which are both polygamists, have regular appointed places, where
during many weeks they congregate in numbers to fight together and to
display their charms before the females.  Dr. W. Kovalevsky informs me that
in Russia he has seen the snow all bloody on the arenas where the
capercailzie have fought; and the black-cocks "make the feathers fly in
every direction," when several "engage in a battle royal."  The elder Brehm
gives a curious account of the Balz, as the love-dances and love-songs of
the Black-cock are called in Germany.  The bird utters almost continuously
the strangest noises:  "he holds his tail up and spreads it out like a fan,
he lifts up his head and neck with all the feathers erect, and stretches
his wings from the body.  Then he takes a few jumps in different
directions, sometimes in a circle, and presses the under part of his beak
so hard against the ground that the chin feathers are rubbed off.  During
these movements he beats his wings and turns round and round.  The more
ardent he grows the more lively he becomes, until at last the bird appears
like a frantic creature."  At such times the black-cocks are so absorbed
that they become almost blind and deaf, but less so than the capercailzie:
hence bird after bird may be shot on the same spot, or even caught by the
hand.  After performing these antics the males begin to fight:  and the
same black-cock, in order to prove his strength over several antagonists,
will visit in the course of one morning several Balz-places, which remain
the same during successive years.  (14.  Brehm, 'Thierleben,' 1867, B. iv.
s. 351.  Some of the foregoing statements are taken from L. Lloyd, 'The
Game Birds of Sweden,' etc., 1867, p. 79.)

The peacock with his long train appears more like a dandy than a warrior,
but he sometimes engages in fierce contests:  the Rev. W. Darwin Fox
informs me that at some little distance from Chester two peacocks became so
excited whilst fighting, that they flew over the whole city, still engaged,
until they alighted on the top of St. John's tower.

The spur, in those gallinaceous birds which are thus provided, is generally
single; but Polyplectron (Fig. 51) has two or more on each leg; and one of
the Blood-pheasants (Ithaginis cruentus) has been seen with five spurs.
The spurs are generally confined to the male, being represented by mere
knobs or rudiments in the female; but the females of the Java peacock (Pavo
muticus) and, as I am informed by Mr. Blyth, of the small fire-backed
pheasant (Euplocamus erythrophthalmus) possess spurs.  In Galloperdix it is
usual for the males to have two spurs, and for the females to have only one
on each leg.  (15.  Jerdon, 'Birds of India':  on Ithaginis, vol. iii. p.
523; on Galloperdix, p. 541.)  Hence spurs may be considered as a masculine
structure, which has been occasionally more or less transferred to the
females.  Like most other secondary sexual characters, the spurs are highly
variable, both in number and development, in the same species.

[Fig.38.  Palamedea cornuta (from Brehm), shewing the double wing-spurs,
and the filament on the head.]

Various birds have spurs on their wings.  But the Egyptian goose
(Chenalopex aegyptiacus) has only "bare obtuse knobs," and these probably
shew us the first steps by which true spurs have been developed in other
species.  In the spur-winged goose, Plectropterus gambensis, the males have
much larger spurs than the females; and they use them, as I am informed by
Mr. Bartlett, in fighting together, so that, in this case, the wing-spurs
serve as sexual weapons; but according to Livingstone, they are chiefly
used in the defence of the young.  The Palamedea (Fig. 38) is armed with a
pair of spurs on each wing; and these are such formidable weapons that a
single blow has been known to drive a dog howling away.  But it does not
appear that the spurs in this case, or in that of some of the spur-winged
rails, are larger in the male than in the female.  (16.  For the Egyptian
goose, see Macgillivray, 'British Birds,' vol. iv. p. 639.  For
Plectropterus, Livingstone's 'Travels,' p. 254.  For Palamedea, Brehm's
'Thierleben,' B. iv. s. 740.  See also on this bird Azara, 'Voyages dans
l'Amerique merid.' tom. iv. 1809, pp. 179, 253.)  In certain plovers,
however, the wing-spurs must be considered as a sexual character.  Thus in
the male of our common peewit (Vanellus cristatus) the tubercle on the
shoulder of the wing becomes more prominent during the breeding-season, and
the males fight together.  In some species of Lobivanellus a similar
tubercle becomes developed during the breeding-season "into a short horny
spur."  In the Australian L. lobatus both sexes have spurs, but these are
much larger in the males than in the females.  In an allied bird, the
Hoplopterus armatus, the spurs do not increase in size during the breeding-
season; but these birds have been seen in Egypt to fight together, in the
same manner as our peewits, by turning suddenly in the air and striking
sideways at each other, sometimes with fatal results.  Thus also they drive
away other enemies.  (17.  See, on our peewit, Mr. R. Carr in 'Land and
Water,' Aug. 8th, 1868, p. 46.  In regard to Lobivanellus, see Jerdon's
'Birds of India,' vol. iii. p. 647, and Gould's 'Handbook of Birds of
Australia,' vol. ii. p. 220.  For the Hoplopterus, see Mr. Allen in the
'Ibis,' vol. v. 1863, p. 156.)

The season of love is that of battle; but the males of some birds, as of
the game-fowl and ruff, and even the young males of the wild turkey and
grouse (18.  Audubon, 'Ornithological Biography,' vol. ii. p. 492; vol. i.
pp. 4-13.), are ready to fight whenever they meet.  The presence of the
female is the teterrima belli causa.  The Bengali baboos make the pretty
little males of the amadavat (Estrelda amandava) fight together by placing
three small cages in a row, with a female in the middle; after a little
time the two males are turned loose, and immediately a desperate battle
ensues.  (19.  Mr. Blyth, 'Land and Water,' 1867, p. 212.)  When many males
congregate at the same appointed spot and fight together, as in the case of
grouse and various other birds, they are generally attended by the females
(20.  Richardson on Tetrao umbellus, 'Fauna Bor. Amer.:  Birds,' 1831, p.
343.  L. Lloyd, 'Game Birds of Sweden,' 1867, pp. 22, 79, on the
capercailzie and black-cock.  Brehm, however, asserts ('Thierleben,' B. iv.
s. 352) that in Germany the grey-hens do not generally attend the Balzen of
the black-cocks, but this is an exception to the common rule; possibly the
hens may lie hidden in the surrounding bushes, as is known to be the case
with the gray-hens in Scandinavia, and with other species in N. America.),
which afterwards pair with the victorious combatants.  But in some cases
the pairing precedes instead of succeeding the combat:  thus according to
Audubon (21.  'Ornithological Biography,' vol. ii. p. 275.), several males
of the Virginian goat-sucker (Caprimulgus virgianus) "court, in a highly
entertaining manner the female, and no sooner has she made her choice, than
her approved gives chase to all intruders, and drives them beyond his
dominions."  Generally the males try to drive away or kill their rivals
before they pair.  It does not, however, appear that the females invariably
prefer the victorious males.  I have indeed been assured by Dr. W.
Kovalevsky that the female capercailzie sometimes steals away with a young
male who has not dared to enter the arena with the older cocks, in the same
manner as occasionally happens with the does of the red-deer in Scotland.
When two males contend in presence of a single female, the victor, no
doubt, commonly gains his desire; but some of these battles are caused by
wandering males trying to distract the peace of an already mated pair.
(22.  Brehm, 'Thierleben,' etc., B. iv. 1867, p. 990.  Audubon,
'Ornithological Biography,' vol. ii. p. 492.)

Even with the most pugnacious species it is probable that the pairing does
not depend exclusively on the mere strength and courage of the male; for
such males are generally decorated with various ornaments, which often
become more brilliant during the breeding-season, and which are sedulously
displayed before the females.  The males also endeavour to charm or excite
their mates by love-notes, songs, and antics; and the courtship is, in many
instances, a prolonged affair.  Hence it is not probable that the females
are indifferent to the charms of the opposite sex, or that they are
invariably compelled to yield to the victorious males.  It is more probable
that the females are excited, either before or after the conflict, by
certain males, and thus unconsciously prefer them.  In the case of Tetrao
umbellus, a good observer (23.  'Land and Water,' July 25, 1868, p. 14.)
goes so far as to believe that the battles of the male "are all a sham,
performed to show themselves to the greatest advantage before the admiring
females who assemble around; for I have never been able to find a maimed
hero, and seldom more than a broken feather."  I shall have to recur to
this subject, but I may here add that with the Tetrao cupido of the United
States, about a score of males assemble at a particular spot, and,
strutting about, make the whole air resound with their extraordinary
noises.  At the first answer from a female the males begin to fight
furiously, and the weaker give way; but then, according to Audubon, both
the victors and vanquished search for the female, so that the females must
either then exert a choice, or the battle must be renewed.  So, again, with
one of the field-starlings of the United States (Sturnella ludoviciana) the
males engage in fierce conflicts, "but at the sight of a female they all
fly after her as if mad."  (24.  Audubon's 'Ornithological Biography;' on
Tetrao cupido, vol. ii. p. 492; on the Sturnus, vol. ii. p. 219.)

VOCAL AND INSTRUMENTAL MUSIC.

With birds the voice serves to express various emotions, such as distress,
fear, anger, triumph, or mere happiness.  It is apparently sometimes used
to excite terror, as in the case of the hissing noise made by some
nestling-birds.  Audubon (25.  'Ornithological Biography,' vol. v. p.
601.), relates that a night-heron (Ardea nycticorax, Linn.), which he kept
tame, used to hide itself when a cat approached, and then "suddenly start
up uttering one of the most frightful cries, apparently enjoying the cat's
alarm and flight."  The common domestic cock clucks to the hen, and the hen
to her chickens, when a dainty morsel is found.  The hen, when she has laid
an egg, "repeats the same note very often, and concludes with the sixth
above, which she holds for a longer time" (26.  The Hon. Daines Barrington,
'Philosophical Transactions,' 1773, p. 252.); and thus she expresses her
joy.  Some social birds apparently call to each other for aid; and as they
flit from tree to tree, the flock is kept together by chirp answering
chirp.  During the nocturnal migrations of geese and other water-fowl,
sonorous clangs from the van may be heard in the darkness overhead,
answered by clangs in the rear.  Certain cries serve as danger signals,
which, as the sportsman knows to his cost, are understood by the same
species and by others.  The domestic cock crows, and the humming-bird
chirps, in triumph over a defeated rival.  The true song, however, of most
birds and various strange cries are chiefly uttered during the breeding-
season, and serve as a charm, or merely as a call-note, to the other sex.

Naturalists are much divided with respect to the object of the singing of
birds.  Few more careful observers ever lived than Montagu, and he
maintained that the "males of song-birds and of many others do not in
general search for the female, but, on the contrary, their business in the
spring is to perch on some conspicuous spot, breathing out their full and
amorous notes, which, by instinct, the female knows, and repairs to the
spot to choose her mate."  (27.  'Ornithological Dictionary,' 1833, p.
475.)  Mr. Jenner Weir informs me that this is certainly the case with the
nightingale.  Bechstein, who kept birds during his whole life, asserts,
"that the female canary always chooses the best singer, and that in a state
of nature the female finch selects that male out of a hundred whose notes
please her most.  (28.  'Naturgeschichte der Stubenvoegel,' 1840, s. 4.
Mr. Harrison Weir likewise writes to me:--"I am informed that the best
singing males generally get a mate first, when they are bred in the same
room.")  There can be no doubt that birds closely attend to each other's
song.  Mr. Weir has told me of the case of a bullfinch which had been
taught to pipe a German waltz, and who was so good a performer that he cost
ten guineas; when this bird was first introduced into a room where other
birds were kept and he began to sing, all the others, consisting of about
twenty linnets and canaries, ranged themselves on the nearest side of their
cages, and listened with the greatest interest to the new performer.  Many
naturalists believe that the singing of birds is almost exclusively "the
effect of rivalry and emulation," and not for the sake of charming their
mates.  This was the opinion of Daines Barrington and White of Selborne,
who both especially attended to this subject.  (29.  'Philosophical
Transactions,' 1773, p. 263.  White's 'Natural History of Selborne,' 1825,
vol. i. p. 246.)  Barrington, however, admits that "superiority in song
gives to birds an amazing ascendancy over others, as is well known to bird-
catchers."

It is certain that there is an intense degree of rivalry between the males
in their singing.  Bird-fanciers match their birds to see which will sing
longest; and I was told by Mr. Yarrell that a first-rate bird will
sometimes sing till he drops down almost dead, or according to Bechstein
(30.  'Naturgesch. der Stubenvoegel,' 1840, s. 252.), quite dead from
rupturing a vessel in the lungs.  Whatever the cause may be, male birds, as
I hear from Mr. Weir, often die suddenly during the season of song.  That
the habit of singing is sometimes quite independent of love is clear, for a
sterile, hybrid canary-bird has been described (31.  Mr. Bold, 'Zoologist,'
1843-44, p. 659.) as singing whilst viewing itself in a mirror, and then
dashing at its own image; it likewise attacked with fury a female canary,
when put into the same cage.  The jealousy excited by the act of singing is
constantly taken advantage of by bird-catchers; a male, in good song, is
hidden and protected, whilst a stuffed bird, surrounded by limed twigs, is
exposed to view.  In this manner, as Mr. Weir informs me, a man has in the
course of a single day caught fifty, and in one instance, seventy, male
chaffinches.  The power and inclination to sing differ so greatly with
birds that although the price of an ordinary male chaffinch is only
sixpence, Mr. Weir saw one bird for which the bird-catcher asked three
pounds; the test of a really good singer being that it will continue to
sing whilst the cage is swung round the owner's head.

That male birds should sing from emulation as well as for charming the
female, is not at all incompatible; and it might have been expected that
these two habits would have concurred, like those of display and pugnacity.
Some authors, however, argue that the song of the male cannot serve to
charm the female, because the females of some few species, such as of the
canary, robin, lark, and bullfinch, especially when in a state of
widowhood, as Bechstein remarks, pour forth fairly melodious strains.  In
some of these cases the habit of singing may be in part attributed to the
females having been highly fed and confined (32.  D. Barrington,
'Philosophical Transactions,' 1773, p. 262.  Bechstein, 'Stubenvoegel,'
1840, s. 4.), for this disturbs all the functions connected with the
reproduction of the species.  Many instances have already been given of the
partial transference of secondary masculine characters to the female, so
that it is not at all surprising that the females of some species should
possess the power of song.  It has also been argued, that the song of the
male cannot serve as a charm, because the males of certain species, for
instance of the robin, sing during the autumn.  (33.  This is likewise the
case with the water-ouzel; see Mr. Hepburn in the 'Zoologist,' 1845-46, p.
1068.)  But nothing is more common than for animals to take pleasure in
practising whatever instinct they follow at other times for some real good.
How often do we see birds which fly easily, gliding and sailing through the
air obviously for pleasure?  The cat plays with the captured mouse, and the
cormorant with the captured fish.  The weaver-bird (Ploceus), when confined
in a cage, amuses itself by neatly weaving blades of grass between the
wires of its cage.  Birds which habitually fight during the breeding-season
are generally ready to fight at all times; and the males of the
capercailzie sometimes hold their Balzen or leks at the usual place of
assemblage during the autumn.  (34.  L. Lloyd, 'Game Birds of Sweden,'
1867, p. 25.)  Hence it is not at all surprising that male birds should
continue singing for their own amusement after the season for courtship is
over.

As shewn in a previous chapter, singing is to a certain extent an art, and
is much improved by practice.  Birds can be taught various tunes, and even
the unmelodious sparrow has learnt to sing like a linnet.  They acquire the
song of their foster parents (35.  Barrington, ibid. p. 264, Bechstein,
ibid. s. 5.), and sometimes that of their neighbours.  (36.  Dureau de la
Malle gives a curious instance ('Annales des Sc. Nat.' 3rd series, Zoolog.,
tom. x. p. 118) of some wild blackbirds in his garden in Paris, which
naturally learnt a republican air from a caged bird.)  All the common
songsters belong to the Order of Insessores, and their vocal organs are
much more complex than those of most other birds; yet it is a singular fact
that some of the Insessores, such as ravens, crows, and magpies, possess
the proper apparatus (37.  Bishop, in 'Todd's Cyclopaedia of Anatomy and
Physiology,' vol. iv. p. 1496.), though they never sing, and do not
naturally modulate their voices to any great extent.  Hunter asserts (38.
As stated by Barrington in 'Philosophical Transactions,' 1773, p. 262.)
that with the true songsters the muscles of the larynx are stronger in the
males than in the females; but with this slight exception there is no
difference in the vocal organs of the two sexes, although the males of most
species sing so much better and more continuously than the females.

It is remarkable that only small birds properly sing.  The Australian genus
Menura, however, must be excepted; for the Menura Alberti, which is about
the size of a half-grown turkey, not only mocks other birds, but "its own
whistle is exceedingly beautiful and varied."  The males congregate and
form "corroborying places," where they sing, raising and spreading their
tails like peacocks, and drooping their wings.  (39.  Gould, 'Handbook to
the Birds of Australia,' vol. i. 1865, pp. 308-310.  See also Mr. T.W. Wood
in the 'Student,' April 1870, p. 125.)  It is also remarkable that birds
which sing well are rarely decorated with brilliant colours or other
ornaments.  Of our British birds, excepting the bullfinch and goldfinch,
the best songsters are plain-coloured.  The kingfisher, bee-eater, roller,
hoopoe, woodpeckers, etc., utter harsh cries; and the brilliant birds of
the tropics are hardly ever songsters.  (40.  See remarks to this effect in
Gould's 'Introduction to the Trochilidae,' 1861, p. 22.)  Hence bright
colours and the power of song seem to replace each other.  We can perceive
that if the plumage did not vary in brightness, or if bright colours were
dangerous to the species, other means would be employed to charm the
females; and melody of voice offers one such means.

[Fig. 39.  Tetrao cupido:  male.  (T.W. Wood.)]

In some birds the vocal organs differ greatly in the two sexes.  In the
Tetrao cupido (Fig. 39) the male has two bare, orange-coloured sacks, one
on each side of the neck; and these are largely inflated when the male,
during the breeding-season, makes his curious hollow sound, audible at a
great distance.  Audubon proved that the sound was intimately connected
with this apparatus (which reminds us of the air-sacks on each side of the
mouth of certain male frogs), for he found that the sound was much
diminished when one of the sacks of a tame bird was pricked, and when both
were pricked it was altogether stopped.  The female has "a somewhat
similar, though smaller naked space of skin on the neck; but this is not
capable of inflation."  (41.  'The Sportsman and Naturalist in Canada,' by
Major W. Ross King, 1866, pp. 144-146.  Mr. T.W. Wood gives in the
'Student' (April 1870, p. 116) an excellent account of the attitude and
habits of this bird during its courtship.  He states that the ear-tufts or
neck-plumes are erected, so that they meet over the crown of the head.  See
his drawing, Fig. 39.)  The male of another kind of grouse (Tetrao
urophasianus), whilst courting the female, has his "bare yellow oesophagus
inflated to a prodigious size, fully half as large as the body"; and he
then utters various grating, deep, hollow tones.  With his neck-feathers
erect, his wings lowered, and buzzing on the ground, and his long pointed
tail spread out like a fan, he displays a variety of grotesque attitudes.
The oesophagus of the female is not in any way remarkable.  (42.
Richardson, 'Fauna Bor. Americana:  Birds,' 1831, p. 359.  Audubon, ibid.
vol. iv. p. 507.)

[Fig. 40.  The Umbrella-bird or Cephalopterus ornatus, male (from Brehm).]

It seems now well made out that the great throat pouch of the European male
bustard (Otis tarda), and of at least four other species, does not, as was
formerly supposed, serve to hold water, but is connected with the utterance
during the breeding-season of a peculiar sound resembling "oak."  (43.  The
following papers have been lately written on this subject:  Prof. A.
Newton, in the 'Ibis,' 1862, p. 107; Dr. Cullen, ibid. 1865, p. 145; Mr.
Flower, in 'Proc. Zool. Soc.' 1865, p. 747; and Dr. Murie, in 'Proc. Zool.
Soc.' 1868, p. 471.  In this latter paper an excellent figure is given of
the male Australian Bustard in full display with the sack distended.  It is
a singular fact that the sack is not developed in all the males of the same
species.)  A crow-like bird inhabiting South America (see Cephalopterus
ornatus, Fig. 40) is called the umbrella-bird, from its immense top knot,
formed of bare white quills surmounted by dark-blue plumes, which it can
elevate into a great dome no less than five inches in diameter, covering
the whole head.  This bird has on its neck a long, thin, cylindrical fleshy
appendage, which is thickly clothed with scale-like blue feathers.  It
probably serves in part as an ornament, but likewise as a resounding
apparatus; for Mr. Bates found that it is connected "with an unusual
development of the trachea and vocal organs."  It is dilated when the bird
utters its singularly deep, loud and long sustained fluty note.  The head-
crest and neck-appendage are rudimentary in the female.  (44.  Bates, 'The
Naturalist on the Amazons,' 1863, vol. ii. p. 284; Wallace, in
'Proceedings, Zoological Society,' 1850, p. 206.  A new species, with a
still larger neck-appendage (C. penduliger), has lately been discovered,
see 'Ibis,' vol. i. p. 457.)

The vocal organs of various web-footed and wading birds are extraordinarily
complex, and differ to a certain extent in the two sexes.  In some cases
the trachea is convoluted, like a French horn, and is deeply embedded in
the sternum.  In the wild swan (Cygnus ferus) it is more deeply embedded in
the adult male than in the adult female or young male.  In the male
Merganser the enlarged portion of the trachea is furnished with an
additional pair of muscles.  (45.  Bishop, in Todd's 'Cyclopaedia of
Anatomy and Physiology,' vol. iv. p. 1499.)  In one of the ducks, however,
namely Anas punctata, the bony enlargement is only a little more developed
in the male than in the female.  (46.  Prof. Newton, 'Proc. Zoolog. Soc.'
1871, p. 651.)  But the meaning of these differences in the trachea of the
two sexes of the Anatidae is not understood; for the male is not always the
more vociferous; thus with the common duck, the male hisses, whilst the
female utters a loud quack.  (47.  The spoonbill (Platalea) has its trachea
convoluted into a figure of eight, and yet this bird (Jerdon, 'Birds of
India,' vol. iii. p. 763) is mute; but Mr. Blyth informs me that the
convolutions are not constantly present, so that perhaps they are now
tending towards abortion.)  In both sexes of one of the cranes (Grus virgo)
the trachea penetrates the sternum, but presents "certain sexual
modifications."  In the male of the black stork there is also a well-marked
sexual difference in the length and curvature of the bronchi.  (48.
'Elements of Comparative Anatomy,' by R. Wagner, Eng. translat. 1845, p.
111.  With respect to the swan, as given above, Yarrell's 'History of
British Birds,' 2nd edition, 1845, vol. iii. p. 193.)  Highly important
structures have, therefore, in these cases been modified according to sex.

It is often difficult to conjecture whether the many strange cries and
notes uttered by male birds during the breeding-season serve as a charm or
merely as a call to the female.  The soft cooing of the turtle-dove and of
many pigeons, it may be presumed, pleases the female.  When the female of
the wild turkey utters her call in the morning, the male answers by a note
which differs from the gobbling noise made, when with erected feathers,
rustling wings and distended wattles, he puffs and struts before her.  (49.
C.L. Bonaparte, quoted in the 'Naturalist Library:  Birds,' vol. xiv. p.
126.)  The spel of the black-cock certainly serves as a call to the female,
for it has been known to bring four or five females from a distance to a
male under confinement; but as the black-cock continues his spel for hours
during successive days, and in the case of the capercailzie "with an agony
of passion," we are led to suppose that the females which are present are
thus charmed.  (50.  L. Lloyd, 'The Game Birds of Sweden,' etc., 1867, pp.
22, 81.)  The voice of the common rook is known to alter during the
breeding-season, and is therefore in some way sexual.  (51.  Jenner,
'Philosophical Transactions,' 1824, p. 20.)  But what shall we say about
the harsh screams of, for instance, some kinds of macaws; have these birds
as bad taste for musical sounds as they apparently have for colour, judging
by the inharmonious contrast of their bright yellow and blue plumage?  It
is indeed possible that without any advantage being thus gained, the loud
voices of many male birds may be the result of the inherited effects of the
continued use of their vocal organs when excited by the strong passions of
love, jealousy and rage; but to this point we shall recur when we treat of
quadrupeds.

We have as yet spoken only of the voice, but the males of various birds
practise, during their courtship, what may be called instrumental music.
Peacocks and Birds of Paradise rattle their quills together.  Turkey-cocks
scrape their wings against the ground, and some kinds of grouse thus
produce a buzzing sound.  Another North American grouse, the Tetrao
umbellus, when with his tail erect, his ruffs displayed, "he shows off his
finery to the females, who lie hid in the neighbourhood," drums by rapidly
striking his wings together above his back, according to Mr. R. Haymond,
and not, as Audubon thought, by striking them against his sides.  The sound
thus produced is compared by some to distant thunder, and by others to the
quick roll of a drum.  The female never drums, "but flies directly to the
place where the male is thus engaged."  The male of the Kalij-pheasant, in
the Himalayas, often makes a singular drumming noise with his wings, not
unlike the sound produced by shaking a stiff piece of cloth."  On the west
coast of Africa the little black-weavers (Ploceus?) congregate in a small
party on the bushes round a small open space, and sing and glide through
the air with quivering wings, "which make a rapid whirring sound like a
child's rattle."  One bird after another thus performs for hours together,
but only during the courting-season.  At this season, and at no other time,
the males of certain night-jars (Caprimulgus) make a strange booming noise
with their wings.  The various species of woodpeckers strike a sonorous
branch with their beaks, with so rapid a vibratory movement that "the head
appears to be in two places at once."  The sound thus produced is audible
at a considerable distance but cannot be described; and I feel sure that
its source would never be conjectured by any one hearing it for the first
time.  As this jarring sound is made chiefly during the breeding-season, it
has been considered as a love-song; but it is perhaps more strictly a love-
call.  The female, when driven from her nest, has been observed thus to
call her mate, who answered in the same manner and soon appeared.  Lastly,
the male hoopoe (Upupa epops) combines vocal and instrumental music; for
during the breeding-season this bird, as Mr. Swinhoe observed, first draws
in air, and then taps the end of its beak perpendicularly down against a
stone or the trunk of a tree, "when the breath being forced down the
tubular bill produces the correct sound."  If the beak is not thus struck
against some object, the sound is quite different.  Air is at the same time
swallowed, and the oesophagus thus becomes much swollen; and this probably
acts as a resonator, not only with the hoopoe, but with pigeons and other
birds.  (52.   For the foregoing facts see, on Birds of Paradise, Brehm,
'Thierleben,' Band iii. s. 325.  On Grouse, Richardson, 'Fauna Bor.
Americ.:  Birds,' pp. 343 and 359; Major W. Ross King, 'The Sportsman in
Canada,' 1866, p. 156; Mr. Haymond, in Prof. Cox's 'Geol. Survey of
Indiana,' p. 227; Audubon, 'American Ornitholog. Biograph.' vol. i. p. 216.
On the Kalij-pheasant, Jerdon, 'Birds of India,' vol. iii. p. 533.  On the
Weavers, Livingstone's 'Expedition to the Zambesi,' 1865, p. 425.  On
Woodpeckers, Macgillivray, 'Hist. of British Birds,' vol. iii. 1840, pp.
84, 88, 89, and 95.  On the Hoopoe, Mr. Swinhoe, in 'Proc. Zoolog. Soc.'
June 23, 1863 and 1871, p. 348.  On the Night-jar, Audubon, ibid. vol. ii.
p. 255, and 'American Naturalist,' 1873, p. 672.  The English Night-jar
likewise makes in the spring a curious noise during its rapid flight.)

[Fig. 41.  Outer tail-feather of Scolopax gallinago (from 'Proc. Zool.
Soc.' 1858).

Fig. 42.  Outer tail-feather of Scolopax frenata.

Fig. 43.  Outer tail-feather of Scolopax javensis.]

In the foregoing cases sounds are made by the aid of structures already
present and otherwise necessary; but in the following cases certain
feathers have been specially modified for the express purpose of producing
sounds.  The drumming, bleating, neighing, or thundering noise (as
expressed by different observers) made by the common snipe (Scolopax
gallinago) must have surprised every one who has ever heard it.  This bird,
during the pairing-season, flies to "perhaps a thousand feet in height,"
and after zig-zagging about for a time descends to the earth in a curved
line, with outspread tail and quivering pinions, and surprising velocity.
The sound is emitted only during this rapid descent.  No one was able to
explain the cause until M. Meves observed that on each side of the tail the
outer feathers are peculiarly formed (Fig. 41), having a stiff sabre-shaped
shaft with the oblique barbs of unusual length, the outer webs being
strongly bound together.  He found that by blowing on these feathers, or by
fastening them to a long thin stick and waving them rapidly through the
air, he could reproduce the drumming noise made by the living bird.  Both
sexes are furnished with these feathers, but they are generally larger in
the male than in the female, and emit a deeper note.  In some species, as
in S. frenata (Fig. 42), four feathers, and in S. javensis (Fig. 43), no
less than eight on each side of the tail are greatly modified.  Different
tones are emitted by the feathers of the different species when waved
through the air; and the Scolopax Wilsonii of the United States makes a
switching noise whilst descending rapidly to the earth.  (53.  See M.
Meves' interesting paper in 'Proc. Zool. Soc.' 1858, p. 199.  For the
habits of the snipe, Macgillivray, 'History of British Birds,' vol. iv. p.
371.  For the American snipe, Capt. Blakiston, 'Ibis,' vol. v. 1863, p.
131.)

[Fig. 44.  Primary wing-feather of a Humming-bird, the Selasphorus
platycercus (from a sketch by Mr. Salvin).
Upper figure, that of male;
lower figure, corresponding feather of female.]

In the male of the Chamaepetes unicolor (a large gallinaceous bird of
America), the first primary wing-feather is arched towards the tip and is
much more attenuated than in the female.  In an allied bird, the Penelope
nigra, Mr. Salvin observed a male, which, whilst it flew downwards "with
outstretched wings, gave forth a kind of crashing rushing noise," like the
falling of a tree.  (54.  Mr. Salvin, in 'Proceedings, Zoological Society,'
1867, p. 160.  I am much indebted to this distinguished ornithologist for
sketches of the feathers of the Chamaepetes, and for other information.)
The male alone of one of the Indian bustards (Sypheotides auritus) has its
primary wing-feathers greatly acuminated; and the male of an allied species
is known to make a humming noise whilst courting the female.  (55.  Jerdon,
'Birds of India,' vol. iii. pp. 618, 621.)  In a widely different group of
birds, namely Humming-birds, the males alone of certain kinds have either
the shafts of their primary wing-feathers broadly dilated, or the webs
abruptly excised towards the extremity.  The male, for instance, of
Selasphorus platycercus, when adult, has the first primary wing-feather
(Fig. 44), thus excised.  Whilst flying from flower to flower he makes "a
shrill, almost whistling noise" (56.  Gould, 'Introduction to the
Trochilidae,' 1861, p. 49.  Salvin, 'Proceedings, Zoological Society,'
1867, p. 160.); but it did not appear to Mr. Salvin that the noise was
intentionally made.

[Fig. 45.  Secondary wing-feathers of Pipra deliciosa (from Mr. Sclater, in
'Proc. Zool. Soc.' 1860).
The three upper feathers, a, b, c, from the male;
the three lower corresponding feathers, d, e, f, from the female.
a and d, fifth secondary wing-feather of male and female, upper surface.
b and e, sixth secondary, upper surface.
c and f, seventh secondary, lower surface.]

Lastly, in several species of a sub-genus of Pipra or Manakin, the males,
as described by Mr. Sclater, have their SECONDARY wing-feathers modified in
a still more remarkable manner.  In the brilliantly-coloured P. deliciosa
the first three secondaries are thick-stemmed and curved towards the body;
in the fourth and fifth (Fig. 45, a) the change is greater; and in the
sixth and seventh (b, c) the shaft "is thickened to an extraordinary
degree, forming a solid horny lump."  The barbs also are greatly changed in
shape, in comparison with the corresponding feathers (d, e, f) in the
female.  Even the bones of the wing, which support these singular feathers
in the male, are said by Mr. Fraser to be much thickened.  These little
birds make an extraordinary noise, the first "sharp note being not unlike
the crack of a whip."  (57.  Sclater, in 'Proceedings, Zoological Society,'
1860, p. 90, and in 'Ibis,' vol. iv. 1862, p. 175.  Also Salvin, in 'Ibis,'
1860, p. 37.)

The diversity of the sounds, both vocal and instrumental, made by the males
of many birds during the breeding-season, and the diversity of the means
for producing such sounds, are highly remarkable.  We thus gain a high idea
of their importance for sexual purposes, and are reminded of the conclusion
arrived at as to insects.  It is not difficult to imagine the steps by
which the notes of a bird, primarily used as a mere call or for some other
purpose, might have been improved into a melodious love song.  In the case
of the modified feathers, by which the drumming, whistling, or roaring
noises are produced, we know that some birds during their courtship
flutter, shake, or rattle their unmodified feathers together; and if the
females were led to select the best performers, the males which possessed
the strongest or thickest, or most attenuated feathers, situated on any
part of the body, would be the most successful; and thus by slow degrees
the feathers might be modified to almost any extent.  The females, of
course, would not notice each slight successive alteration in shape, but
only the sounds thus produced.  It is a curious fact that in the same class
of animals, sounds so different as the drumming of the snipe's tail, the
tapping of the woodpecker's beak, the harsh trumpet-like cry of certain
water-fowl, the cooing of the turtle-dove, and the song of the nightingale,
should all be pleasing to the females of the several species.  But we must
not judge of the tastes of distinct species by a uniform standard; nor must
we judge by the standard of man's taste.  Even with man, we should remember
what discordant noises, the beating of tom-toms and the shrill notes of
reeds, please the ears of savages.  Sir S. Baker remarks (58.  'The Nile
Tributaries of Abyssinia,' 1867, p. 203.), that "as the stomach of the Arab
prefers the raw meat and reeking liver taken hot from the animal, so does
his ear prefer his equally coarse and discordant music to all other."

LOVE ANTICS AND DANCES.

The curious love gestures of some birds have already been incidentally
noticed; so that little need here be added.  In Northern America large
numbers of a grouse, the Tetrao phasianellus, meet every morning during the
breeding-season on a selected level spot, and here they run round and round
in a circle of about fifteen or twenty feet in diameter, so that the ground
is worn quite bare, like a fairy-ring.  In these Partridge-dances, as they
are called by the hunters, the birds assume the strangest attitudes, and
run round, some to the left and some to the right.  Audubon describes the
males of a heron (Ardea herodias) as walking about on their long legs with
great dignity before the females, bidding defiance to their rivals.  With
one of the disgusting carrion-vultures (Cathartes jota) the same naturalist
states that "the gesticulations and parade of the males at the beginning of
the love-season are extremely ludicrous."  Certain birds perform their
love-antics on the wing, as we have seen with the black African weaver,
instead of on the ground.  During the spring our little white-throat
(Sylvia cinerea) often rises a few feet or yards in the air above some
bush, and "flutters with a fitful and fantastic motion, singing all the
while, and then drops to its perch."  The great English bustard throws
himself into indescribably odd attitudes whilst courting the female, as has
been figured by Wolf.  An allied Indian bustard (Otis bengalensis) at such
times "rises perpendicularly into the air with a hurried flapping of his
wings, raising his crest and puffing out the feathers of his neck and
breast, and then drops to the ground;" he repeats this manoeuvre several
times, at the same time humming in a peculiar tone.  Such females as happen
to be near "obey this saltatory summons," and when they approach he trails
his wings and spreads his tail like a turkey-cock.  (59.  For Tetrao
phasianellus, see Richardson, 'Fauna, Bor. America,' p. 361, and for
further particulars Capt. Blakiston, 'Ibis,' 1863, p. 125.  For the
Cathartes and Ardea, Audubon, 'Ornithological Biography,' vol. ii. p. 51,
and vol. iii. p. 89.  On the White-throat, Macgillivray, 'History of
British Birds,' vol. ii. p. 354.  On the Indian Bustard, Jerdon, 'Birds of
India,' vol. iii. p. 618.)

[Fig. 46.  Bower-bird, Chlamydera maculata, with bower (from Brehm).]

But the most curious case is afforded by three allied genera of Australian
birds, the famous Bower-birds,--no doubt the co-descendants of some ancient
species which first acquired the strange instinct of constructing bowers
for performing their love-antics.  The bowers (Fig. 46), which, as we shall
hereafter see, are decorated with feathers, shells, bones, and leaves, are
built on the ground for the sole purpose of courtship, for their nests are
formed in trees.  Both sexes assist in the erection of the bowers, but the
male is the principal workman.  So strong is this instinct that it is
practised under confinement, and Mr. Strange has described (60.  Gould,
'Handbook to the Birds of Australia,' vol. i. pp. 444, 449, 455.  The bower
of the Satin Bower-bird may be seen in the Zoological Society's Gardens,
Regent's Park.) the habits of some Satin Bower-birds which he kept in an
aviary in New South Wales.  "At times the male will chase the female all
over the aviary, then go to the bower, pick up a gay feather or a large
leaf, utter a curious kind of note, set all his feathers erect, run round
the bower and become so excited that his eyes appear ready to start from
his head; he continues opening first one wing then the other, uttering a
low, whistling note, and, like the domestic cock, seems to be picking up
something from the ground, until at last the female goes gently towards
him."  Captain Stokes has described the habits and "play-houses" of another
species, the Great Bower-bird, which was seen "amusing itself by flying
backwards and forwards, taking a shell alternately from each side, and
carrying it through the archway in its mouth."  These curious structures,
formed solely as halls of assemblage, where both sexes amuse themselves and
pay their court, must cost the birds much labour.  The bower, for instance,
of the Fawn-breasted species, is nearly four feet in length, eighteen
inches in height, and is raised on a thick platform of sticks.

DECORATION.

I will first discuss the cases in which the males are ornamented either
exclusively or in a much higher degree than the females, and in a
succeeding chapter those in which both sexes are equally ornamented, and
finally the rare cases in which the female is somewhat more brightly-
coloured than the male.  As with the artificial ornaments used by savage
and civilised men, so with the natural ornaments of birds, the head is the
chief seat of decoration.  (61.  See remarks to this effect, on the
'Feeling of Beauty among Animals,' by Mr. J. Shaw, in the 'Athenaeum,' Nov.
24th, 1866, p. 681.)  The ornaments, as mentioned at the commencement of
this chapter, are wonderfully diversified.  The plumes on the front or back
of the head consist of variously-shaped feathers, sometimes capable of
erection or expansion, by which their beautiful colours are fully
displayed.  Elegant ear-tufts (Fig. 39) are occasionally present.  The head
is sometimes covered with velvety down, as with the pheasant; or is naked
and vividly coloured.  The throat, also, is sometimes ornamented with a
beard, wattles, or caruncles.  Such appendages are generally brightly-
coloured, and no doubt serve as ornaments, though not always ornamental in
our eyes; for whilst the male is in the act of courting the female, they
often swell and assume vivid tints, as in the male turkey.  At such times
the fleshy appendages about the head of the male Tragopan pheasant
(Ceriornis Temminckii) swell into a large lappet on the throat and into two
horns, one on each side of the splendid top-knot; and these are then
coloured of the most intense blue which I have ever beheld.  (62.  See Dr.
Murie's account with coloured figures in 'Proceedings, Zoological Society,'
1872, p. 730.)  The African hornbill (Bucorax abyssinicus) inflates the
scarlet bladder-like wattle on its neck, and with its wings drooping and
tail expanded "makes quite a grand appearance."  (63.  Mr. Monteiro,
'Ibis,' vol. iv. 1862, p. 339.)  Even the iris of the eye is sometimes more
brightly-coloured in the male than in the female; and this is frequently
the case with the beak, for instance, in our common blackbird.  In Buceros
corrugatus, the whole beak and immense casque are coloured more
conspicuously in the male than in the female; and "the oblique grooves upon
the sides of the lower mandible are peculiar to the male sex."  (64.  'Land
and Water,' 1868, p. 217.)

The head, again, often supports fleshy appendages, filaments, and solid
protuberances.  These, if not common to both sexes, are always confined to
the males.  The solid protuberances have been described in detail by Dr. W.
Marshall (65.  'Ueber die Schaedelhoecker,' etc., 'Niederland. Archiv. fur
Zoologie,' B. I. Heft 2, 1872.), who shews that they are formed either of
cancellated bone coated with skin, or of dermal and other tissues.  With
mammals true horns are always supported on the frontal bones, but with
birds various bones have been modified for this purpose; and in species of
the same group the protuberances may have cores of bone, or be quite
destitute of them, with intermediate gradations connecting these two
extremes.  Hence, as Dr. Marshall justly remarks, variations of the most
different kinds have served for the development through sexual selection of
these ornamental appendages.  Elongated feathers or plumes spring from
almost every part of the body.  The feathers on the throat and breast are
sometimes developed into beautiful ruffs and collars.  The tail-feathers
are frequently increased in length; as we see in the tail-coverts of the
peacock, and in the tail itself of the Argus pheasant.  With the peacock
even the bones of the tail have been modified to support the heavy tail-
coverts.  (66.  Dr. W. Marshall, 'Ueber den Vogelschwanz,' ibid. B. I. Heft
2, 1872.)  The body of the Argus is not larger than that of a fowl; yet the
length from the end of the beak to the extremity of the tail is no less
than five feet three inches (67.  Jardine's 'Naturalist Library:  Birds,'
vol. xiv. p. 166.), and that of the beautifully ocellated secondary wing-
feathers nearly three feet.  In a small African night-jar (Cosmetornis
vexillarius) one of the primary wing-feathers, during the breeding-season,
attains a length of twenty-six inches, whilst the bird itself is only ten
inches in length.  In another closely-allied genus of night-jars, the
shafts of the elongated wing-feathers are naked, except at the extremity,
where there is a disc.  (68.  Sclater, in the 'Ibis,' vol. vi. 1864, p.
114; Livingstone, 'Expedition to the Zambesi,' 1865, p. 66.)  Again, in
another genus of night-jars, the tail-feathers are even still more
prodigiously developed.  In general the feathers of the tail are more often
elongated than those of the wings, as any great elongation of the latter
impedes flight.  We thus see that in closely-allied birds ornaments of the
same kind have been gained by the males through the development of widely
different feathers.

It is a curious fact that the feathers of species belonging to very
distinct groups have been modified in almost exactly the same peculiar
manner.  Thus the wing-feathers in one of the above-mentioned night-jars
are bare along the shaft, and terminate in a disc; or are, as they are
sometimes called, spoon or racket-shaped.  Feathers of this kind occur in
the tail of a motmot (Eumomota superciliaris), of a king-fisher, finch,
humming-bird, parrot, several Indian drongos (Dicrurus and Edolius, in one
of which the disc stands vertically), and in the tail of certain birds of
paradise.  In these latter birds, similar feathers, beautifully ocellated,
ornament the head, as is likewise the case with some gallinaceous birds.
In an Indian bustard (Sypheotides auritus) the feathers forming the ear-
tufts, which are about four inches in length, also terminate in discs.
(69.  Jerdon, 'Birds of India,' vol. iii. p. 620.)  It is a most singular
fact that the motmots, as Mr. Salvin has clearly shewn (70.  'Proceedings,
Zoological Society,' 1873, p. 429.), give to their tail feathers the
racket-shape by biting off the barbs, and, further, that this continued
mutilation has produced a certain amount of inherited effect.

[Fig. 47.  Paradisea Papuana (T.W. Wood).]

Again, the barbs of the feathers in various widely-distinct birds are
filamentous or plumose, as with some herons, ibises, birds of paradise, and
Gallinaceae.  In other cases the barbs disappear, leaving the shafts bare
from end to end; and these in the tail of the Paradisea apoda attain a
length of thirty-four inches (71.  Wallace, in 'Annals and Magazine of
Natural History,' vol. xx. 1857, p. 416, and in his 'Malay Archipelago,'
vol. ii. 1869, p. 390.):  in P. Papuana (Fig. 47) they are much shorter and
thin.  Smaller feathers when thus denuded appear like bristles, as on the
breast of the turkey-cock.  As any fleeting fashion in dress comes to be
admired by man, so with birds a change of almost any kind in the structure
or colouring of the feathers in the male appears to have been admired by
the female.  The fact of the feathers in widely distinct groups having been
modified in an analogous manner no doubt depends primarily on all the
feathers having nearly the same structure and manner of development, and
consequently tending to vary in the same manner.  We often see a tendency
to analogous variability in the plumage of our domestic breeds belonging to
distinct species.  Thus top-knots have appeared in several species.  In an
extinct variety of the turkey, the top-knot consisted of bare quills
surmounted with plumes of down, so that they somewhat resembled the racket-
shaped feathers above described.  In certain breeds of the pigeon and fowl
the feathers are plumose, with some tendency in the shafts to be naked.  In
the Sebastopol goose the scapular feathers are greatly elongated, curled,
or even spirally twisted, with the margins plumose.  (72.  See my work on
'The Variation of Animals and Plants under Domestication,' vol. i. pp. 289,
293.)

In regard to colour, hardly anything need here be said, for every one knows
how splendid are the tints of many birds, and how harmoniously they are
combined.  The colours are often metallic and iridescent.  Circular spots
are sometimes surrounded by one or more differently shaded zones, and are
thus converted into ocelli.  Nor need much be said on the wonderful
difference between the sexes of many birds.  The common peacock offers a
striking instance.  Female birds of paradise are obscurely coloured and
destitute of all ornaments, whilst the males are probably the most highly
decorated of all birds, and in so many different ways that they must be
seen to be appreciated.  The elongated and golden-orange plumes which
spring from beneath the wings of the Paradisea apoda, when vertically
erected and made to vibrate, are described as forming a sort of halo, in
the centre of which the head "looks like a little emerald sun with its rays
formed by the two plumes."  (73.  Quoted from M. de Lafresnaye in 'Annals
and Mag. of Natural History,' vol. xiii. 1854, p. 157:  see also Mr.
Wallace's much fuller account in vol. xx. 1857, p. 412, and in his 'Malay
Archipelago.')  In another most beautiful species the head is bald, "and
of a rich cobalt blue, crossed by several lines of black velvety feathers."
(74.  Wallace, 'The Malay Archipelago,' vol. ii. 1869, p. 405.)

[Fig. 48.  Lophornis ornatus, male and female (from Brehm).

Fig. 49.  Spathura underwoodi, male and female (from Brehm).]

Male humming-birds (Figs. 48 and 49) almost vie with birds of paradise in
their beauty, as every one will admit who has seen Mr. Gould's splendid
volumes, or his rich collection.  It is very remarkable in how many
different ways these birds are ornamented.  Almost every part of their
plumage has been taken advantage of, and modified; and the modifications
have been carried, as Mr. Gould shewed me, to a wonderful extreme in some
species belonging to nearly every sub-group.  Such cases are curiously like
those which we see in our fancy breeds, reared by man for the sake of
ornament; certain individuals originally varied in one character, and other
individuals of the same species in other characters; and these have been
seized on by man and much augmented--as shewn by the tail of the fantail-
pigeon, the hood of the jacobin, the beak and wattle of the carrier, and so
forth.  The sole difference between these cases is that in the one, the
result is due to man's selection, whilst in the other, as with humming-
birds, birds of paradise, etc., it is due to the selection by the females
of the more beautiful males.

I will mention only one other bird, remarkable from the extreme contrast in
colour between the sexes, namely the famous bell-bird (Chasmorhynchus
niveus) of S. America, the note of which can be distinguished at the
distance of nearly three miles, and astonishes every one when first hearing
it.  The male is pure white, whilst the female is dusky-green; and white is
a very rare colour in terrestrial species of moderate size and inoffensive
habits.  The male, also, as described by Waterton, has a spiral tube,
nearly three inches in length, which rises from the base of the beak.  It
is jet-black, dotted over with minute downy feathers.  This tube can be
inflated with air, through a communication with the palate; and when not
inflated hangs down on one side.  The genus consists of four species, the
males of which are very distinct, whilst the females, as described by Mr.
Sclater in a very interesting paper, closely resemble each other, thus
offering an excellent instance of the common rule that within the same
group the males differ much more from each other than do the females.  In a
second species (C. nudicollis) the male is likewise snow-white, with the
exception of a large space of naked skin on the throat and round the eyes,
which during the breeding-season is of a fine green colour.  In a third
species (C. tricarunculatus) the head and neck alone of the male are white,
the rest of the body being chestnut-brown, and the male of this species is
provided with three filamentous projections half as long as the body--one
rising from the base of the beak, and the two others from the corners of
the mouth.   (75.  Mr. Sclater, 'Intellectual Observer,' Jan. 1867.
Waterton's 'Wanderings,' p. 118.  See also Mr. Salvin's interesting paper,
with a plate, in the 'Ibis,' 1865, p. 90.)

The coloured plumage and certain other ornaments of the adult males are
either retained for life, or are periodically renewed during the summer and
breeding-season.  At this same season the beak and naked skin about the
head frequently change colour, as with some herons, ibises, gulls, one of
the bell-birds just noticed, etc.  In the white ibis, the cheeks, the
inflatable skin of the throat, and the basal portion of the beak then
become crimson.  (76.  'Land and Water,' 1867, p. 394.)  In one of the
rails, Gallicrex cristatus, a large red caruncle is developed during this
period on the head of the male.  So it is with a thin horny crest on the
beak of one of the pelicans, P. erythrorhynchus; for, after the breeding-
season, these horny crests are shed, like horns from the heads of stags,
and the shore of an island in a lake in Nevada was found covered with these
curious exuviae.  (77.  Mr. D.G. Elliot, in 'Proc. Zool. Soc.' 1869, p.
589.)

Changes of colour in the plumage according to the season depend, firstly on
a double annual moult, secondly on an actual change of colour in the
feathers themselves, and thirdly on their dull-coloured margins being
periodically shed, or on these three processes more or less combined.  The
shedding of the deciduary margins may be compared with the shedding of
their down by very young birds; for the down in most cases arises from the
summits of the first true feathers.  (78.  Nitzsch's 'Pterylography,'
edited by P.L. Sclater, Ray Society, 1867, p. 14.)

With respect to the birds which annually undergo a double moult, there are,
firstly, some kinds, for instance snipes, swallow-plovers (Glareolae), and
curlews, in which the two sexes resemble each other, and do not change
colour at any season.  I do not know whether the winter plumage is thicker
and warmer than the summer plumage, but warmth seems the most probable end
attained of a double moult, where there is no change of colour.  Secondly,
there are birds, for instance, certain species of Totanus and other
Grallatores, the sexes of which resemble each other, but in which the
summer and winter plumage differ slightly in colour.  The difference,
however, in these cases is so small that it can hardly be an advantage to
them; and it may, perhaps, be attributed to the direct action of the
different conditions to which the birds are exposed during the two seasons.
Thirdly, there are many other birds the sexes of which are alike, but which
are widely different in their summer and winter plumage.  Fourthly, there
are birds the sexes of which differ from each other in colour; but the
females, though moulting twice, retain the same colours throughout the
year, whilst the males undergo a change of colour, sometimes a great one,
as with certain bustards.  Fifthly and lastly, there are birds the sexes of
which differ from each other in both their summer and winter plumage; but
the male undergoes a greater amount of change at each recurrent season than
the female--of which the ruff (Machetes pugnax) offers a good instance.

With respect to the cause or purpose of the differences in colour between
the summer and winter plumage, this may in some instances, as with the
ptarmigan (79.  The brown mottled summer plumage of the ptarmigan is of as
much importance to it, as a protection, as the white winter plumage; for in
Scandinavia during the spring, when the snow has disappeared, this bird is
known to suffer greatly from birds of prey, before it has acquired its
summer dress:  see Wilhelm von Wright, in Lloyd, 'Game Birds of Sweden,'
1867, p. 125.), serve during both seasons as a protection.  When the
difference between the two plumages is slight it may perhaps be attributed,
as already remarked, to the direct action of the conditions of life.  But
with many birds there can hardly be a doubt that the summer plumage is
ornamental, even when both sexes are alike.  We may conclude that this is
the case with many herons, egrets, etc., for they acquire their beautiful
plumes only during the breeding-season.  Moreover, such plumes, top-knots,
etc., though possessed by both sexes, are occasionally a little more
developed in the male than in the female; and they resemble the plumes and
ornaments possessed by the males alone of other birds.  It is also known
that confinement, by affecting the reproductive system of male birds,
frequently checks the development of their secondary sexual characters, but
has no immediate influence on any other characters; and I am informed by
Mr. Bartlett that eight or nine specimens of the Knot (Tringa canutus)
retained their unadorned winter plumage in the Zoological Gardens
throughout the year, from which fact we may infer that the summer plumage,
though common to both sexes, partakes of the nature of the exclusively
masculine plumage of many other birds.  (80.  In regard to the previous
statements on moulting, see, on snipes, etc., Macgillivray, 'Hist. Brit.
Birds,' vol. iv. p. 371; on Glareolae, curlews, and bustards, Jerdon,
'Birds of India,' vol. iii. pp. 615, 630, 683; on Totanus, ibid. p. 700; on
the plumes of herons, ibid. p. 738, and Macgillivray, vol. iv. pp. 435 and
444, and Mr. Stafford Allen, in the 'Ibis,' vol. v. 1863, p. 33.)

From the foregoing facts, more especially from neither sex of certain birds
changing colour during either annual moult, or changing so slightly that
the change can hardly be of any service to them, and from the females of
other species moulting twice yet retaining the same colours throughout the
year, we may conclude that the habit of annually moulting twice has not
been acquired in order that the male should assume an ornamental character
during the breeding-season; but that the double moult, having been
originally acquired for some distinct purpose, has subsequently been taken
advantage of in certain cases for gaining a nuptial plumage.

It appears at first sight a surprising circumstance that some closely-
allied species should regularly undergo a double annual moult, and others
only a single one.  The ptarmigan, for instance, moults twice or even
thrice in the year, and the blackcock only once:  some of the splendidly
coloured honey-suckers (Nectariniae) of India and some sub-genera of
obscurely coloured pipits (Anthus) have a double, whilst others have only a
single annual moult.  (81.  On the moulting of the ptarmigan, see Gould's
'Birds of Great Britain.'  On the honey-suckers, Jerdon, 'Birds of India,'
vol. i. pp. 359, 365, 369.  On the moulting of Anthus, see Blyth, in
'Ibis,' 1867, p. 32.)  But the gradations in the manner of moulting, which
are known to occur with various birds, shew us how species, or whole
groups, might have originally acquired their double annual moult, or having
once gained the habit, have again lost it.  With certain bustards and
plovers the vernal moult is far from complete, some feathers being renewed,
and some changed in colour.  There is also reason to believe that with
certain bustards and rail-like birds, which properly undergo a double
moult, some of the older males retain their nuptial plumage throughout the
year.  A few highly modified feathers may merely be added during the spring
to the plumage, as occurs with the disc-formed tail-feathers of certain
drongos (Bhringa) in India, and with the elongated feathers on the back,
neck, and crest of certain herons.  By such steps as these, the vernal
moult might be rendered more and more complete, until a perfect double
moult was acquired.  Some of the birds of paradise retain their nuptial
feathers throughout the year, and thus have only a single moult; others
cast them directly after the breeding-season, and thus have a double moult;
and others again cast them at this season during the first year, but not
afterwards; so that these latter species are intermediate in their manner
of moulting.  There is also a great difference with many birds in the
length of time during which the two annual plumages are retained; so that
the one might come to be retained for the whole year, and the other
completely lost.  Thus in the spring Machetes pugnax retains his ruff for
barely two months.  In Natal the male widow-bird (Chera progne) acquires
his fine plumage and long tail-feathers in December or January, and loses
them in March; so that they are retained only for about three months.  Most
species, which undergo a double moult, keep their ornamental feathers for
about six months.  The male, however, of the wild Gallus bankiva retains
his neck-hackles for nine or ten months; and when these are cast off, the
underlying black feathers on the neck are fully exposed to view.  But with
the domesticated descendant of this species, the neck-hackles of the male
are immediately replaced by new ones; so that we here see, as to part of
the plumage, a double moult changed under domestication into a single
moult.  (82.  For the foregoing statements in regard to partial moults, and
on old males retaining their nuptial plumage, see Jerdon, on bustards and
plovers, in 'Birds of India,' vol. iii. pp. 617, 637, 709, 711.  Also Blyth
in 'Land and Water,' 1867, p. 84.  On the moulting of Paradisea, see an
interesting article by Dr. W. Marshall, 'Archives Neerlandaises,' tom. vi.
1871.  On the Vidua, 'Ibis,' vol. iii. 1861, p. 133.  On the Drongo-
shrikes, Jerdon, ibid. vol. i. p. 435.  On the vernal moult of the Herodias
bubulcus, Mr. S.S. Allen, in 'Ibis,' 1863, p. 33.  On Gallus bankiva,
Blyth, in 'Annals and Mag. of Natural History,' vol. i. 1848, p. 455; see,
also, on this subject, my 'Variation of Animals under Domestication,' vol.
i. p. 236.)

The common drake (Anas boschas), after the breeding-season, is well known
to lose his male plumage for a period of three months, during which time he
assumes that of the female.  The male pin-tail duck (Anas acuta) loses his
plumage for the shorter period of six weeks or two months; and Montagu
remarks that "this double moult within so short a time is a most
extraordinary circumstance, that seems to bid defiance to all human
reasoning."  But the believer in the gradual modification of species will
be far from feeling surprise at finding gradations of all kinds.  If the
male pin-tail were to acquire his new plumage within a still shorter
period, the new male feathers would almost necessarily be mingled with the
old, and both with some proper to the female; and this apparently is the
case with the male of a not distantly-allied bird, namely the Merganser
serrator, for the males are said to "undergo a change of plumage, which
assimilates them in some measure to the female."  By a little further
acceleration in the process, the double moult would be completely lost.
(83.  See Macgillivray, 'Hist. British Birds' (vol. v. pp. 34, 70, and
223), on the moulting of the Anatidae, with quotations from Waterton and
Montagu.  Also Yarrell, 'History of British Birds,' vol. iii. p. 243.)

Some male birds, as before stated, become more brightly coloured in the
spring, not by a vernal moult, but either by an actual change of colour in
the feathers, or by their obscurely-coloured deciduary margins being shed.
Changes of colour thus caused may last for a longer or shorter time.  In
the Pelecanus onocrotalus a beautiful rosy tint, with lemon-coloured marks
on the breast, overspreads the whole plumage in the spring; but these
tints, as Mr. Sclater states, "do not last long, disappearing generally in
about six weeks or two months after they have been attained."  Certain
finches shed the margins of their feathers in the spring, and then become
brighter coloured, while other finches undergo no such change.  Thus the
Fringilla tristis of the United States (as well as many other American
species) exhibits its bright colours only when the winter is past, whilst
our goldfinch, which exactly represents this bird in habits, and our
siskin, which represents it still more closely in structure, undergo no
such annual change.  But a difference of this kind in the plumage of allied
species is not surprising, for with the common linnet, which belongs to the
same family, the crimson forehead and breast are displayed only during the
summer in England, whilst in Madeira these colours are retained throughout
the year.  (84.  On the pelican, see Sclater, in 'Proc. Zool. Soc.' 1868,
p. 265.  On the American finches, see Audubon, 'Ornithological Biography,'
vol. i. pp. 174, 221, and Jerdon, 'Birds of India,' vol. ii. p. 383.  On
the Fringilla cannabina of Madeira, Mr. E. Vernon Harcourt, 'Ibis,' vol. v.
1863, p. 230.)

DISPLAY BY MALE BIRDS OF THEIR PLUMAGE.

Ornaments of all kinds, whether permanently or temporarily gained, are
sedulously displayed by the males, and apparently serve to excite, attract,
or fascinate the females.  But the males will sometimes display their
ornaments, when not in the presence of the females, as occasionally occurs
with grouse at their balz-places, and as may be noticed with the peacock;
this latter bird, however, evidently wishes for a spectator of some kind,
and, as I have often seen, will shew off his finery before poultry, or even
pigs.  (85.  See also 'Ornamental Poultry,' by Rev. E.S. Dixon, 1848, p.
8.)  All naturalists who have closely attended to the habits of birds,
whether in a state of nature or under confinement, are unanimously of
opinion that the males take delight in displaying their beauty.  Audubon
frequently speaks of the male as endeavouring in various ways to charm the
female.  Mr. Gould, after describing some peculiarities in a male humming-
bird, says he has no doubt that it has the power of displaying them to the
greatest advantage before the female.  Dr. Jerdon (86.  'Birds of India,'
introduct., vol. i. p. xxiv.; on the peacock, vol. iii. p. 507.  See
Gould's 'Introduction to Trochilidae,' 1861, pp. 15 and 111.) insists that
the beautiful plumage of the male serves "to fascinate and attract the
female."  Mr. Bartlett, at the Zoological Gardens, expressed himself to me
in the strongest terms to the same effect.

[Fig. 50.  Rupicola crocea, male (T.W. Wood).]

It must be a grand sight in the forests of India "to come suddenly on
twenty or thirty pea-fowl, the males displaying their gorgeous trains, and
strutting about in all the pomp of pride before the gratified females."
The wild turkey-cock erects his glittering plumage, expands his finely-
zoned tail and barred wing-feathers, and altogether, with his crimson and
blue wattles, makes a superb, though, to our eyes, grotesque appearance.
Similar facts have already been given with respect to grouse of various
kinds.  Turning to another Order:  The male Rupicola crocea (Fig. 50) is
one of the most beautiful birds in the world, being of a splendid orange,
with some of the feathers curiously truncated and plumose.  The female is
brownish-green, shaded with red, and has a much smaller crest.  Sir R.
Schomburgk has described their courtship; he found one of their meeting-
places where ten males and two females were present.  The space was from
four to five feet in diameter, and appeared to have been cleared of every
blade of grass and smoothed as if by human hands.  A male "was capering, to
the apparent delight of several others.  Now spreading its wings, throwing
up its head, or opening its tail like a fan; now strutting about with a
hopping gait until tired, when it gabbled some kind of note, and was
relieved by another.  Thus three of them successively took the field, and
then, with self-approbation, withdrew to rest."  The Indians, in order to
obtain their skins, wait at one of the meeting-places till the birds are
eagerly engaged in dancing, and then are able to kill with their poisoned
arrows four or five males, one after the other.  (87.  'Journal of R.
Geograph. Soc.' vol. x. 1840, p. 236.)  With birds of paradise a dozen or
more full-plumaged males congregate in a tree to hold a dancing-party, as
it is called by the natives:  and here they fly about, raise their wings,
elevate their exquisite plumes, and make them vibrate, and the whole tree
seems, as Mr. Wallace remarks, to be filled with waving plumes.  When thus
engaged, they become so absorbed that a skilful archer may shoot nearly the
whole party.  These birds, when kept in confinement in the Malay
Archipelago, are said to take much care in keeping their feathers clean;
often spreading them out, examining them, and removing every speck of dirt.
One observer, who kept several pairs alive, did not doubt that the display
of the male was intended to please the female.  (88.  'Annals and Mag. of
Nat. Hist.' vol. xiii. 1854, p. 157; also Wallace, ibid. vol. xx. 1857, p.
412, and 'The Malay Archipelago,' vol. ii. 1869, p. 252.  Also Dr. Bennett,
as quoted by Brehm, 'Thierleben,' B. iii. s. 326.)

[Fig. 51.  Polyplectron chinquis, male (T.W. Wood).]

The Gold and Amherst pheasants during their courtship not only expand and
raise their splendid frills, but twist them, as I have myself seen,
obliquely towards the female on whichever side she may be standing,
obviously in order that a large surface may be displayed before her.  (89.
Mr. T.W. Wood has given ('The Student,' April 1870, p. 115) a full account
of this manner of display, by the Gold pheasant and by the Japanese
pheasant, Ph. versicolor; and he calls it the lateral or one-sided
display.)  They likewise turn their beautiful tails and tail-coverts a
little towards the same side.  Mr. Bartlett has observed a male
Polyplectron (Fig. 51) in the act of courtship, and has shewn me a specimen
stuffed in the attitude then assumed.  The tail and wing-feathers of this
bird are ornamented with beautiful ocelli, like those on the peacock's
train.  Now when the peacock displays himself, he expands and erects his
tail transversely to his body, for he stands in front of the female, and
has to shew off, at the same time, his rich blue throat and breast.  But
the breast of the Polyplectron is obscurely coloured, and the ocelli are
not confined to the tail-feathers.  Consequently the Polyplectron does not
stand in front of the female; but he erects and expands his tail-feathers a
little obliquely, lowering the expanded wing on the same side, and raising
that on the opposite side.  In this attitude the ocelli over the whole body
are exposed at the same time before the eyes of the admiring female in one
grand bespangled expanse.  To whichever side she may turn, the expanded
wings and the obliquely-held tail are turned towards her.  The male
Tragopan pheasant acts in nearly the same manner, for he raises the
feathers of the body, though not the wing itself, on the side which is
opposite to the female, and which would otherwise be concealed, so that
nearly all the beautifully spotted feathers are exhibited at the same time.

[Fig. 52.  Side view of male Argus pheasant, whilst displaying before the
female.  Observed and sketched from nature by T.W. Wood.]

The Argus pheasant affords a much more remarkable case.  The immensely
developed secondary wing-feathers are confined to the male; and each is
ornamented with a row of from twenty to twenty-three ocelli, above an inch
in diameter.  These feathers are also elegantly marked with oblique stripes
and rows of spots of a dark colour, like those on the skin of a tiger and
leopard combined.  These beautiful ornaments are hidden until the male
shows himself off before the female.  He then erects his tail, and expands
his wing-feathers into a great, almost upright, circular fan or shield,
which is carried in front of the body.  The neck and head are held on one
side, so that they are concealed by the fan; but the bird in order to see
the female, before whom he is displaying himself, sometimes pushes his head
between two of the long wing-feathers (as Mr. Bartlett has seen), and then
presents a grotesque appearance.  This must be a frequent habit with the
bird in a state of nature, for Mr. Bartlett and his son on examining some
perfect skins sent from the East, found a place between two of the feathers
which was much frayed, as if the head had here frequently been pushed
through.  Mr. Wood thinks that the male can also peep at the female on one
side, beyond the margin of the fan.

The ocelli on the wing-feathers are wonderful objects; for they are so
shaded that, as the Duke of Argyll remarks (90.  'The Reign of Law,' 1867,
p. 203.), they stand out like balls lying loosely within sockets.  When I
looked at the specimen in the British Museum, which is mounted with the
wings expanded and trailing downwards, I was however greatly disappointed,
for the ocelli appeared flat, or even concave.  But Mr. Gould soon made the
case clear to me, for he held the feathers erect, in the position in which
they would naturally be displayed, and now, from the light shining on them
from above, each ocellus at once resembled the ornament called a ball and
socket.  These feathers have been shown to several artists, and all have
expressed their admiration at the perfect shading.  It may well be asked,
could such artistically shaded ornaments have been formed by means of
sexual selection?  But it will be convenient to defer giving an answer to
this question until we treat in the next chapter of the principle of
gradation.

The foregoing remarks relate to the secondary wing-feathers, but the
primary wing-feathers, which in most gallinaceous birds are uniformly
coloured, are in the Argus pheasant equally wonderful.  They are of a soft
brown tint with numerous dark spots, each of which consists of two or three
black dots with a surrounding dark zone.  But the chief ornament is a space
parallel to the dark-blue shaft, which in outline forms a perfect second
feather lying within the true feather.  This inner part is coloured of a
lighter chestnut, and is thickly dotted with minute white points.  I have
shewn this feather to several persons, and many have admired it even more
than the ball and socket feathers, and have declared that it was more like
a work of art than of nature.  Now these feathers are quite hidden on all
ordinary occasions, but are fully displayed, together with the long
secondary feathers, when they are all expanded together so as to form the
great fan or shield.

The case of the male Argus pheasant is eminently interesting, because it
affords good evidence that the most refined beauty may serve as a sexual
charm, and for no other purpose.  We must conclude that this is the case,
as the secondary and primary wing-feathers are not at all displayed, and
the ball and socket ornaments are not exhibited in full perfection until
the male assumes the attitude of courtship.  The Argus pheasant does not
possess brilliant colours, so that his success in love appears to depend on
the great size of his plumes, and on the elaboration of the most elegant
patterns.  Many will declare that it is utterly incredible that a female
bird should be able to appreciate fine shading and exquisite patterns.  It
is undoubtedly a marvellous fact that she should possess this almost human
degree of taste.  He who thinks that he can safely gauge the discrimination
and taste of the lower animals may deny that the female Argus pheasant can
appreciate such refined beauty; but he will then be compelled to admit that
the extraordinary attitudes assumed by the male during the act of
courtship, by which the wonderful beauty of his plumage is fully displayed,
are purposeless; and this is a conclusion which I for one will never admit.

Although so many pheasants and allied gallinaceous birds carefully display
their plumage before the females, it is remarkable, as Mr. Bartlett informs
me, that this is not the case with the dull-coloured Eared and Cheer
pheasants (Crossoptilon auritum and Phasianus wallichii); so that these
birds seem conscious that they have little beauty to display.  Mr. Bartlett
has never seen the males of either of these species fighting together,
though he has not had such good opportunities for observing the Cheer as
the Eared pheasant.  Mr. Jenner Weir, also, finds that all male birds with
rich or strongly-characterised plumage are more quarrelsome than the dull-
coloured species belonging to the same groups.  The goldfinch, for
instance, is far more pugnacious than the linnet, and the blackbird than
the thrush.  Those birds which undergo a seasonal change of plumage
likewise become much more pugnacious at the period when they are most gaily
ornamented.  No doubt the males of some obscurely-coloured birds fight
desperately together, but it appears that when sexual selection has been
highly influential, and has given bright colours to the males of any
species, it has also very often given a strong tendency to pugnacity.  We
shall meet with nearly analogous cases when we treat of mammals.  On the
other hand, with birds the power of song and brilliant colours have rarely
been both acquired by the males of the same species; but in this case the
advantage gained would have been the same, namely success in charming the
female.  Nevertheless it must be owned that the males of several
brilliantly coloured birds have had their feathers specially modified for
the sake of producing instrumental music, though the beauty of this cannot
be compared, at least according to our taste, with that of the vocal music
of many songsters.

We will now turn to male birds which are not ornamented in any high degree,
but which nevertheless display during their courtship whatever attractions
they may possess.  These cases are in some respects more curious than the
foregoing, and have been but little noticed.  I owe the following facts to
Mr. Weir, who has long kept confined birds of many kinds, including all the
British Fringillidae and Emberizidae.  The facts have been selected from a
large body of valuable notes kindly sent me by him.  The bullfinch makes
his advances in front of the female, and then puffs out his breast, so that
many more of the crimson feathers are seen at once than otherwise would be
the case.  At the same time he twists and bows his black tail from side to
side in a ludicrous manner.  The male chaffinch also stands in front of the
female, thus shewing his red breast and "blue bell," as the fanciers call
his head; the wings at the same time being slightly expanded, with the pure
white bands on the shoulders thus rendered conspicuous.  The common linnet
distends his rosy breast, slightly expands his brown wings and tail, so as
to make the best of them by exhibiting their white edgings.  We must,
however, be cautious in concluding that the wings are spread out solely for
display, as some birds do so whose wings are not beautiful.  This is the
case with the domestic cock, but it is always the wing on the side opposite
to the female which is expanded, and at the same time scraped on the
ground.  The male goldfinch behaves differently from all other finches:
his wings are beautiful, the shoulders being black, with the dark-tipped
wing-feathers spotted with white and edged with golden yellow.  When he
courts the female, he sways his body from side to side, and quickly turns
his slightly expanded wings first to one side, then to the other, with a
golden flashing effect.  Mr. Weir informs me that no other British finch
turns thus from side to side during his courtship, not even the closely-
allied male siskin, for he would not thus add to his beauty.

Most of the British Buntings are plain coloured birds; but in the spring
the feathers on the head of the male reed-bunting (Emberiza schoeniculus)
acquire a fine black colour by the abrasion of the dusky tips; and these
are erected during the act of courtship.  Mr. Weir has kept two species of
Amadina from Australia:  the A. castanotis is a very small and chastely
coloured finch, with a dark tail, white rump, and jet-black upper tail-
coverts, each of the latter being marked with three large conspicuous oval
spots of white.  (91.  For the description of these birds, see Gould's
'Handbook to the Birds of Australia,' vol. i. 1865, p. 417.)  This species,
when courting the female, slightly spreads out and vibrates these parti-
coloured tail-coverts in a very peculiar manner.  The male Amadina Lathami
behaves very differently, exhibiting before the female his brilliantly
spotted breast, scarlet rump, and scarlet upper tail-coverts.  I may here
add from Dr. Jerdon that the Indian bulbul (Pycnonotus hoemorrhous) has its
under tail-coverts of a crimson colour, and these, it might be thought,
could never be well exhibited; but the bird "when excited often spreads
them out laterally, so that they can be seen even from above."  (92.
'Birds of India,' vol. ii. p. 96.)  The crimson under tail-coverts of some
other birds, as with one of the woodpeckers, Picus major, can be seen
without any such display.  The common pigeon has iridescent feathers on the
breast, and every one must have seen how the male inflates his breast
whilst courting the female, thus shewing them off to the best advantage.
One of the beautiful bronze-winged pigeons of Australia (Ocyphaps lophotes)
behaves, as described to me by Mr. Weir, very differently:  the male,
whilst standing before the female, lowers his head almost to the ground,
spreads out and raises his tail, and half expands his wings.  He then
alternately and slowly raises and depresses his body, so that the
iridescent metallic feathers are all seen at once, and glitter in the sun.

Sufficient facts have now been given to shew with what care male birds
display their various charms, and this they do with the utmost skill.
Whilst preening their feathers, they have frequent opportunities for
admiring themselves, and of studying how best to exhibit their beauty.  But
as all the males of the same species display themselves in exactly the same
manner, it appears that actions, at first perhaps intentional, have become
instinctive.  If so, we ought not to accuse birds of conscious vanity; yet
when we see a peacock strutting about, with expanded and quivering tail-
feathers, he seems the very emblem of pride and vanity.

The various ornaments possessed by the males are certainly of the highest
importance to them, for in some cases they have been acquired at the
expense of greatly impeded powers of flight or of running.  The African
night-jar (Cosmetornis), which during the pairing-season has one of its
primary wing-feathers developed into a streamer of very great length, is
thereby much retarded in its flight, although at other times remarkable for
its swiftness.  The "unwieldy size" of the secondary wing-feathers of the
male Argus pheasant is said "almost entirely to deprive the bird of
flight."  The fine plumes of male birds of paradise trouble them during a
high wind.  The extremely long tail-feathers of the male widow-birds
(Vidua) of Southern Africa render "their flight heavy;" but as soon as
these are cast off they fly as well as the females.  As birds always breed
when food is abundant, the males probably do not suffer much inconvenience
in searching for food from their impeded powers of movement; but there can
hardly be a doubt that they must be much more liable to be struck down by
birds of prey.  Nor can we doubt that the long train of the peacock and the
long tail and wing-feathers of the Argus pheasant must render them an
easier prey to any prowling tiger-cat than would otherwise be the case.
Even the bright colours of many male birds cannot fail to make them
conspicuous to their enemies of all kinds.  Hence, as Mr. Gould has
remarked, it probably is that such birds are generally of a shy
disposition, as if conscious that their beauty was a source of danger, and
are much more difficult to discover or approach, than the sombre coloured
and comparatively tame females or than the young and as yet unadorned
males.  (93.  On the Cosmetornis, see Livingstone's 'Expedition to the
Zambesi,' 1865, p. 66.  On the Argus pheasant, Jardine's 'Nat. Hist. Lib.:
Birds,' vol. xiv. p. 167.  On Birds of Paradise, Lesson, quoted by Brehm,
'Thierleben,' B. iii. s. 325.  On the widow-bird, Barrow's 'Travels in
Africa,' vol. i. p. 243, and 'Ibis,' vol. iii. 1861 p. 133.  Mr. Gould, on
the shyness of male birds, 'Handbook to Birds of Australia,' vol. i. 1865,
pp. 210, 457.)

It is a more curious fact that the males of some birds which are provided
with special weapons for battle, and which in a state of nature are so
pugnacious that they often kill each other, suffer from possessing certain
ornaments.  Cock-fighters trim the hackles and cut off the combs and gills
of their cocks; and the birds are then said to be dubbed.  An undubbed
bird, as Mr. Tegetmeier insists, "is at a fearful disadvantage; the comb
and gills offer an easy hold to his adversary's beak, and as a cock always
strikes where he holds, when once he has seized his foe, he has him
entirely in his power.  Even supposing that the bird is not killed, the
loss of blood suffered by an undubbed cock is much greater than that
sustained by one that has been trimmed."  (94.  Tegetmeier, 'The Poultry
Book,' 1866, p. 139.)  Young turkey-cocks in fighting always seize hold of
each other's wattles; and I presume that the old birds fight in the same
manner.  It may perhaps be objected that the comb and wattles are not
ornamental, and cannot be of service to the birds in this way; but even to
our eyes, the beauty of the glossy black Spanish cock is much enhanced by
his white face and crimson comb; and no one who has ever seen the splendid
blue wattles of the male Tragopan pheasant distended in courtship can for a
moment doubt that beauty is the object gained.  From the foregoing facts we
clearly see that the plumes and other ornaments of the males must be of the
highest importance to them; and we further see that beauty is even
sometimes more important than success in battle.


CHAPTER XIV.

BIRDS--continued.

Choice exerted by the female--Length of courtship--Unpaired birds--Mental
qualities and taste for the beautiful--Preference or antipathy shewn by the
female for particular males--Variability of birds--Variations sometimes
abrupt--Laws of variation--Formation of ocelli--Gradations of character--
Case of Peacock, Argus pheasant, and Urosticte.

When the sexes differ in beauty or in the power of singing, or in producing
what I have called instrumental music, it is almost invariably the male who
surpasses the female.  These qualities, as we have just seen, are evidently
of high importance to the male.  When they are gained for only a part of
the year it is always before the breeding-season.  It is the male alone who
elaborately displays his varied attractions, and often performs strange
antics on the ground or in the air, in the presence of the female.  Each
male drives away, or if he can, kills his rivals.  Hence we may conclude
that it is the object of the male to induce the female to pair with him,
and for this purpose he tries to excite or charm her in various ways; and
this is the opinion of all those who have carefully studied the habits of
living birds.  But there remains a question which has an all important
bearing on sexual selection, namely, does every male of the same species
excite and attract the female equally?  Or does she exert a choice, and
prefer certain males?  This latter question can be answered in the
affirmative by much direct and indirect evidence.  It is far more difficult
to decide what qualities determine the choice of the females; but here
again we have some direct and indirect evidence that it is to a large
extent the external attractions of the male; though no doubt his vigour,
courage, and other mental qualities come into play.  We will begin with the
indirect evidence.

LENGTH OF COURTSHIP.

The lengthened period during which both sexes of certain birds meet day
after day at an appointed place probably depends partly on the courtship
being a prolonged affair, and partly on reiteration in the act of pairing.
Thus in Germany and Scandinavia the balzen or leks of the black-cocks last
from the middle of March, all through April into May.  As many as forty or
fifty, or even more birds congregate at the leks; and the same place is
often frequented during successive years.  The lek of the capercailzie
lasts from the end of March to the middle or even end of May.  In North
America "the partridge dances" of the Tetrao phasianellus "last for a month
or more."  Other kinds of grouse, both in North America and Eastern Siberia
(1.  Nordman describes ('Bull. Soc. Imp. des Nat. Moscou,' 1861, tom.
xxxiv. p. 264) the balzen of Tetrao urogalloides in Amur Land.  He
estimated the number of birds assembled at above a hundred, not counting
the females, which lie hid in the surrounding bushes.  The noises uttered
differ from those of T. urogallus.), follow nearly the same habits.  The
fowlers discover the hillocks where the ruffs congregate by the grass being
trampled bare, and this shews that the same spot is long frequented.  The
Indians of Guiana are well acquainted with the cleared arenas, where they
expect to find the beautiful cocks of the Rock; and the natives of New
Guinea know the trees where from ten to twenty male birds of paradise in
full plumage congregate.  In this latter case it is not expressly stated
that the females meet on the same trees, but the hunters, if not specially
asked, would probably not mention their presence, as their skins are
valueless.  Small parties of an African weaver (Ploceus) congregate, during
the breeding-season, and perform for hours their graceful evolutions.
Large numbers of the Solitary snipe (Scolopax major) assemble during dusk
in a morass; and the same place is frequented for the same purpose during
successive years; here they may be seen running about "like so many large
rats," puffing out their feathers, flapping their wings, and uttering the
strangest cries.  (2.  With respect to the assemblages of the above named
grouse, see Brehm, 'Thierleben,' B. iv. s. 350; also L. Lloyd, 'Game Birds
of Sweden,' 1867, pp. 19, 78.  Richardson, 'Fauna Bor. Americana:  Birds,'
p. 362.  References in regard to the assemblages of other birds have
already been given.  On Paradisea, see Wallace, in 'Annals and Mag. of Nat.
Hist.' vol. xx. 1857, p. 412.  On the snipe, Lloyd, ibid. p. 221.)

Some of the above birds,--the black-cock, capercailzie, pheasant-grouse,
ruff, solitary snipe, and perhaps others,--are, as is believed,
polygamists.  With such birds it might have been thought that the stronger
males would simply have driven away the weaker, and then at once have taken
possession of as many females as possible; but if it be indispensable for
the male to excite or please the female, we can understand the length of
the courtship and the congregation of so many individuals of both sexes at
the same spot.  Certain strictly monogamous species likewise hold nuptial
assemblages; this seems to be the case in Scandinavia with one of the
ptarmigans, and their leks last from the middle of March to the middle of
May.  In Australia the lyre-bird (Menura superba) forms "small round
hillocks," and the M. Alberti scratches for itself shallow holes, or, as
they are called by the natives, "corroborying places," where it is believed
both sexes assemble.  The meetings of the M. superba are sometimes very
large; and an account has lately been published (3.  Quoted by Mr. T.W.
Wood, in the 'Student,' April 1870, p. 125.) by a traveller, who heard in a
valley beneath him, thickly covered with scrub, "a din which completely
astonished" him; on crawling onwards he beheld, to his amazement, about one
hundred and fifty of the magnificent lyre-cocks, "ranged in order of
battle, and fighting with indescribable fury."  The bowers of the Bower-
birds are the resort of both sexes during the breeding-season; and "here
the males meet and contend with each other for the favours of the female,
and here the latter assemble and coquet with the males."  With two of the
genera, the same bower is resorted to during many years.  (4.  Gould,
'Handbook to the Birds of Australia,' vol. i. pp. 300, 308, 448, 451.  On
the ptarmigan, above alluded to, see Lloyd, ibid. p. 129.)

The common magpie (Corvus pica, Linn.), as I have been informed by the Rev.
W. Darwin Fox, used to assemble from all parts of Delamere Forest, in order
to celebrate the "great magpie marriage."  Some years ago these birds
abounded in extraordinary numbers, so that a gamekeeper killed in one
morning nineteen males, and another killed by a single shot seven birds at
roost together.  They then had the habit of assembling very early in the
spring at particular spots, where they could be seen in flocks, chattering,
sometimes fighting, bustling and flying about the trees.  The whole affair
was evidently considered by the birds as one of the highest importance.
Shortly after the meeting they all separated, and were then observed by Mr.
Fox and others to be paired for the season.  In any district in which a
species does not exist in large numbers, great assemblages cannot, of
course, be held, and the same species may have different habits in
different countries.  For instance, I have heard of only one instance, from
Mr. Wedderburn, of a regular assemblage of black game in Scotland, yet
these assemblages are so well known in Germany and Scandinavia that they
have received special names.

UNPAIRED BIRDS.

From the facts now given, we may conclude that the courtship of birds
belonging to widely different groups, is often a prolonged, delicate, and
troublesome affair.  There is even reason to suspect, improbable as this
will at first appear, that some males and females of the same species,
inhabiting the same district, do not always please each other, and
consequently do not pair.  Many accounts have been published of either the
male or female of a pair having been shot, and quickly replaced by another.
This has been observed more frequently with the magpie than with any other
bird, owing perhaps to its conspicuous appearance and nest.  The
illustrious Jenner states that in Wiltshire one of a pair was daily shot no
less than seven times successively, "but all to no purpose, for the
remaining magpie soon found another mate"; and the last pair reared their
young.  A new partner is generally found on the succeeding day; but Mr.
Thompson gives the case of one being replaced on the evening of the same
day.  Even after the eggs are hatched, if one of the old birds is destroyed
a mate will often be found; this occurred after an interval of two days, in
a case recently observed by one of Sir J. Lubbock's keepers.  (5.  On
magpies, Jenner, in 'Philosophical Transactions,' 1824, p. 21.
Macgillivray, 'Hist. British Birds,' vol. i. p. 570.  Thompson, in 'Annals
and Magazine of Natural History,' vol. viii. 1842, p. 494.)  The first and
most obvious conjecture is that male magpies must be much more numerous
than females; and that in the above cases, as well as in many others which
could be given, the males alone had been killed.  This apparently holds
good in some instances, for the gamekeepers in Delamere Forest assured Mr.
Fox that the magpies and carrion-crows which they formerly killed in
succession in large numbers near their nests, were all males; and they
accounted for this fact by the males being easily killed whilst bringing
food to the sitting females.  Macgillivray, however, gives, on the
authority of an excellent observer, an instance of three magpies
successively killed on the same nest, which were all females; and another
case of six magpies successively killed whilst sitting on the same eggs,
which renders it probable that most of them were females; though, as I hear
from Mr. Fox, the male will sit on the eggs when the female is killed.

Sir J. Lubbock's gamekeeper has repeatedly shot, but how often he could not
say, one of a pair of jays (Garrulus glandarius), and has never failed
shortly afterwards to find the survivor re-matched.  Mr. Fox, Mr. F. Bond,
and others have shot one of a pair of carrion-crows (Corvus corone), but
the nest was soon again tenanted by a pair.  These birds are rather common;
but the peregrine-falcon (Falco peregrinus) is rare, yet Mr. Thompson
states that in Ireland "if either an old male or female be killed in the
breeding-season (not an uncommon circumstance), another mate is found
within a very few days, so that the eyries, notwithstanding such
casualties, are sure to turn out their complement of young."  Mr. Jenner
Weir has known the same thing with the peregrine-falcons at Beachy Head.
The same observer informs me that three kestrels (Falco tinnunculus), all
males, were killed one after the other whilst attending the same nest; two
of these were in mature plumage, but the third was in the plumage of the
previous year.  Even with the rare golden eagle (Aquila chrysaetos), Mr.
Birkbeck was assured by a trustworthy gamekeeper in Scotland, that if one
is killed, another is soon found.  So with the white owl (Strix flammea),
"the survivor readily found a mate, and the mischief went on."

White of Selborne, who gives the case of the owl, adds that he knew a man,
who from believing that partridges when paired were disturbed by the males
fighting, used to shoot them; and though he had widowed the same female
several times, she always soon found a fresh partner.  This same naturalist
ordered the sparrows, which deprived the house-martins of their nests, to
be shot; but the one which was left, "be it cock or hen, presently procured
a mate, and so for several times following."  I could add analogous cases
relating to the chaffinch, nightingale, and redstart.  With respect to the
latter bird (Phoenicura ruticilla), a writer expresses much surprise how
the sitting female could so soon have given effectual notice that she was a
widow, for the species was not common in the neighbourhood.  Mr. Jenner
Weir has mentioned to me a nearly similar case; at Blackheath he never sees
or hears the note of the wild bullfinch, yet when one of his caged males
has died, a wild one in the course of a few days has generally come and
perched near the widowed female, whose call-note is not loud.  I will give
only one other fact, on the authority of this same observer; one of a pair
of starlings (Sturnus vulgaris) was shot in the morning; by noon a new mate
was found; this was again shot, but before night the pair was complete; so
that the disconsolate widow or widower was thrice consoled during the same
day.  Mr. Engleheart also informs me that he used during several years to
shoot one of a pair of starlings which built in a hole in a house at
Blackheath; but the loss was always immediately repaired.  During one
season he kept an account, and found that he had shot thirty-five birds
from the same nest; these consisted of both males and females, but in what
proportion he could not say:  nevertheless, after all this destruction, a
brood was reared.  (6.  On the peregrine falcon, see Thompson, 'Nat. Hist.
of Ireland:  Birds,' vol. i. 1849, p. 39.  On owls, sparrows, and
partridges, see White, 'Nat. Hist. of Selborne,' edit. of 1825, vol. i. p.
139.  On the Phoenicura, see Loudon's 'Mag. of Nat. Hist.' vol. vii. 1834,
p. 245.  Brehm ('Thierleben,' B. iv. s. 991) also alludes to cases of birds
thrice mated during the same day.)

These facts well deserve attention.  How is it that there are birds enough
ready to replace immediately a lost mate of either sex?  Magpies, jays,
carrion-crows, partridges, and some other birds, are always seen during the
spring in pairs, and never by themselves; and these offer at first sight
the most perplexing cases.  But birds of the same sex, although of course
not truly paired, sometimes live in pairs or in small parties, as is known
to be the case with pigeons and partridges.  Birds also sometimes live in
triplets, as has been observed with starlings, carrion-crows, parrots, and
partridges.  With partridges two females have been known to live with one
male, and two males with one female.  In all such cases it is probable that
the union would be easily broken; and one of the three would readily pair
with a widow or widower.  The males of certain birds may occasionally be
heard pouring forth their love-song long after the proper time, shewing
that they have either lost or never gained a mate.  Death from accident or
disease of one of a pair would leave the other free and single; and there
is reason to believe that female birds during the breeding-season are
especially liable to premature death.  Again, birds which have had their
nests destroyed, or barren pairs, or retarded individuals, would easily be
induced to desert their mates, and would probably be glad to take what
share they could of the pleasures and duties of rearing offspring although
not their own.  (7.  See White ('Nat. Hist. of Selborne,' 1825, vol. i. p.
140) on the existence, early in the season, of small coveys of male
partridges, of which fact I have heard other instances.  See Jenner, on the
retarded state of the generative organs in certain birds, in 'Phil.
Transact.' 1824.  In regard to birds living in triplets, I owe to Mr.
Jenner Weir the cases of the starlings and parrots, and to Mr. Fox, of
partridges; on carrion-crows, see the 'Field,' 1868, p. 415.  On various
male birds singing after the proper period, see Rev. L. Jenyns,
'Observations in Natural History,' 1846, p. 87.)  Such contingencies as
these probably explain most of the foregoing cases.  (8.  The following
case has been given ('The Times,' Aug. 6, 1868) by the Rev. F.O. Morris, on
the authority of the Hon. and Rev. O.W. Forester.  "The gamekeeper here
found a hawk's nest this year, with five young ones on it.  He took four
and killed them, but left one with its wings clipped as a decoy to destroy
the old ones by.  They were both shot next day, in the act of feeding the
young one, and the keeper thought it was done with.  The next day he came
again and found two other charitable hawks, who had come with an adopted
feeling to succour the orphan.  These two he killed, and then left the
nest.  On returning afterwards he found two more charitable individuals on
the same errand of mercy.  One of these he killed; the other he also shot,
but could not find.  No more came on the like fruitless errand.")
Nevertheless, it is a strange fact that within the same district, during
the height of the breeding-season, there should be so many males and
females always ready to repair the loss of a mated bird.  Why do not such
spare birds immediately pair together?  Have we not some reason to suspect,
and the suspicion has occurred to Mr. Jenner Weir, that as the courtship of
birds appears to be in many cases prolonged and tedious, so it occasionally
happens that certain males and females do not succeed, during the proper
season, in exciting each other's love, and consequently do not pair?  This
suspicion will appear somewhat less improbable after we have seen what
strong antipathies and preferences female birds occasionally evince towards
particular males.

MENTAL QUALITIES OF BIRDS, AND THEIR TASTE FOR THE BEAUTIFUL.

Before we further discuss the question whether the females select the more
attractive males or accept the first whom they may encounter, it will be
advisable briefly to consider the mental powers of birds.  Their reason is
generally, and perhaps justly, ranked as low; yet some facts could be given
leading to an opposite conclusion.  (9.  I am indebted to Prof. Newton for
the following passage from Mr. Adam's 'Travels of a Naturalist,' 1870, p.
278.  Speaking of Japanese nut-hatches in confinement, he says:  "Instead
of the more yielding fruit of the yew, which is the usual food of the nut-
hatch of Japan, at one time I substituted hard hazel-nuts.  As the bird was
unable to crack them, he placed them one by one in his water-glass,
evidently with the notion that they would in time become softer--an
interesting proof of intelligence on the part of these birds.")  Low powers
of reasoning, however, are compatible, as we see with mankind, with strong
affections, acute perception, and a taste for the beautiful; and it is with
these latter qualities that we are here concerned.  It has often been said
that parrots become so deeply attached to each other that when one dies the
other pines for a long time; but Mr. Jenner Weir thinks that with most
birds the strength of their affection has been much exaggerated.
Nevertheless when one of a pair in a state of nature has been shot, the
survivor has been heard for days afterwards uttering a plaintive call; and
Mr. St. John gives various facts proving the attachment of mated birds.
(10.  'A Tour in Sutherlandshire,' vol. i. 1849, p. 185.  Dr. Buller says
('Birds of New Zealand,' 1872, p. 56) that a male King Lory was killed; and
the female "fretted and moped, refused her food, and died of a broken
heart.")  Mr. Bennett relates (11.  'Wanderings in New South Wales,' vol.
ii. 1834, p. 62.) that in China after a drake of the beautiful mandarin
Teal had been stolen, the duck remained disconsolate, though sedulously
courted by another mandarin drake, who displayed before her all his charms.
After an interval of three weeks the stolen drake was recovered, and
instantly the pair recognised each other with extreme joy.  On the other
hand, starlings, as we have seen, may be consoled thrice in the same day
for the loss of their mates.  Pigeons have such excellent local memories,
that they have been known to return to their former homes after an interval
of nine months, yet, as I hear from Mr. Harrison Weir, if a pair which
naturally would remain mated for life be separated for a few weeks during
the winter, and afterwards matched with other birds, the two when brought
together again, rarely, if ever, recognise each other.

Birds sometimes exhibit benevolent feelings; they will feed the deserted
young ones even of distinct species, but this perhaps ought to be
considered as a mistaken instinct.  They will feed, as shewn in an earlier
part of this work, adult birds of their own species which have become
blind.  Mr. Buxton gives a curious account of a parrot which took care of a
frost-bitten and crippled bird of a distinct species, cleansed her
feathers, and defended her from the attacks of the other parrots which
roamed freely about his garden.  It is a still more curious fact that these
birds apparently evince some sympathy for the pleasures of their fellows.
When a pair of cockatoos made a nest in an acacia tree, "it was ridiculous
to see the extravagant interest taken in the matter by the others of the
same species."  These parrots, also, evinced unbounded curiosity, and
clearly had "the idea of property and possession."  (12.  'Acclimatization
of Parrots,' by C. Buxton, M.P., 'Annals and Mag. of Nat. Hist.' Nov. 1868,
p. 381.)  They have good memories, for in the Zoological Gardens they have
plainly recognised their former masters after an interval of some months.

Birds possess acute powers of observation.  Every mated bird, of course,
recognises its fellow.  Audubon states that a certain number of mocking-
thrushes (Mimus polyglottus) remain all the year round in Louisiana, whilst
others migrate to the Eastern States; these latter, on their return, are
instantly recognised, and always attacked, by their southern brethren.
Birds under confinement distinguish different persons, as is proved by the
strong and permanent antipathy or affection which they shew, without any
apparent cause, towards certain individuals.  I have heard of numerous
instances with jays, partridges, canaries, and especially bullfinches.  Mr.
Hussey has described in how extraordinary a manner a tamed partridge
recognised everybody:  and its likes and dislikes were very strong.  This
bird seemed "fond of gay colours, and no new gown or cap could be put on
without catching his attention."  (13.  The 'Zoologist,' 1847-48, p. 1602.)
Mr. Hewitt has described the habits of some ducks (recently descended from
wild birds), which, at the approach of a strange dog or cat, would rush
headlong into the water, and exhaust themselves in their attempts to
escape; but they knew Mr. Hewitt's own dogs and cats so well that they
would lie down and bask in the sun close to them.  They always moved away
from a strange man, and so they would from the lady who attended them if
she made any great change in her dress.  Audubon relates that he reared and
tamed a wild turkey which always ran away from any strange dog; this bird
escaped into the woods, and some days afterwards Audubon saw, as he
thought, a wild turkey, and made his dog chase it; but, to his
astonishment, the bird did not run away, and the dog, when he came up, did
not attack the bird, for they mutually recognised each other as old
friends.  (14.  Hewitt on wild ducks, 'Journal of Horticulture,' Jan. 13,
1863, p. 39.  Audubon on the wild turkey, 'Ornithological Biography,' vol.
i. p. 14.  On the mocking-thrush, ibid. vol. i. p. 110.)

Mr. Jenner Weir is convinced that birds pay particular attention to the
colours of other birds, sometimes out of jealousy, and sometimes as a sign
of kinship.  Thus he turned a reed-bunting (Emberiza schoeniculus), which
had acquired its black head-dress, into his aviary, and the new-comer was
not noticed by any bird, except by a bullfinch, which is likewise black-
headed.  This bullfinch was a very quiet bird, and had never before
quarrelled with any of its comrades, including another reed-bunting, which
had not as yet become black-headed:  but the reed-bunting with a black head
was so unmercifully treated that it had to be removed.  Spiza cyanea,
during the breeding-season, is of a bright blue colour; and though
generally peaceable, it attacked S. ciris, which has only the head blue,
and completely scalped the unfortunate bird.  Mr. Weir was also obliged to
turn out a robin, as it fiercely attacked all the birds in his aviary with
any red in their plumage, but no other kinds; it actually killed a red-
breasted crossbill, and nearly killed a goldfinch.  On the other hand, he
has observed that some birds, when first introduced, fly towards the
species which resemble them most in colour, and settle by their sides.

As male birds display their fine plumage and other ornaments with so much
care before the females, it is obviously probable that these appreciate the
beauty of their suitors.  It is, however, difficult to obtain direct
evidence of their capacity to appreciate beauty.  When birds gaze at
themselves in a looking-glass (of which many instances have been recorded)
we cannot feel sure that it is not from jealousy of a supposed rival,
though this is not the conclusion of some observers.  In other cases it is
difficult to distinguish between mere curiosity and admiration.  It is
perhaps the former feeling which, as stated by Lord Lilford (15.  The
'Ibis,' vol. ii. 1860, p. 344.), attracts the ruff towards any bright
object, so that, in the Ionian Islands, "it will dart down to a bright-
coloured handkerchief, regardless of repeated shots."  The common lark is
drawn down from the sky, and is caught in large numbers, by a small mirror
made to move and glitter in the sun.  Is it admiration or curiosity which
leads the magpie, raven, and some other birds to steal and secrete bright
objects, such as silver articles or jewels?

Mr. Gould states that certain humming-birds decorate the outsides of their
nests "with the utmost taste; they instinctively fasten thereon beautiful
pieces of flat lichen, the larger pieces in the middle, and the smaller on
the part attached to the branch.  Now and then a pretty feather is
intertwined or fastened to the outer sides, the stem being always so placed
that the feather stands out beyond the surface."  The best evidence,
however, of a taste for the beautiful is afforded by the three genera of
Australian bower-birds already mentioned.  Their bowers (Fig. 46), where
the sexes congregate and play strange antics, are variously constructed,
but what most concerns us is, that they are decorated by the several
species in a different manner.  The Satin bower-bird collects gaily-
coloured articles, such as the blue tail-feathers of parrakeets, bleached
bones and shells, which it sticks between the twigs or arranges at the
entrance.  Mr. Gould found in one bower a neatly-worked stone tomahawk and
a slip of blue cotton, evidently procured from a native encampment.  These
objects are continually re-arranged, and carried about by the birds whilst
at play.  The bower of the Spotted bower-bird "is beautifully lined with
tall grasses, so disposed that the heads nearly meet, and the decorations
are very profuse."  Round stones are used to keep the grass-stems in their
proper places, and to make divergent paths leading to the bower.  The
stones and shells are often brought from a great distance.  The Regent
bird, as described by Mr. Ramsay, ornaments its short bower with bleached
land-shells belonging to five or six species, and with "berries of various
colours, blue, red, and black, which give it when fresh a very pretty
appearance.  Besides these there were several newly-picked leaves and young
shoots of a pinkish colour, the whole showing a decided taste for the
beautiful."  Well may Mr. Gould say that "these highly decorated halls of
assembly must be regarded as the most wonderful instances of bird-
architecture yet discovered;" and the taste, as we see, of the several
species certainly differs.  (16.  On the ornamented nests of humming-birds,
Gould, 'Introduction to the Trochilidae,' 1861, p. 19.  On the bower-birds,
Gould, 'Handbook to the Birds of Australia,' 1865, vol. i. pp. 444-461.
Ramsay, in the 'Ibis,' 1867, p. 456.)

PREFERENCE FOR PARTICULAR MALES BY THE FEMALES.

Having made these preliminary remarks on the discrimination and taste of
birds, I will give all the facts known to me which bear on the preference
shewn by the female for particular males.  It is certain that distinct
species of birds occasionally pair in a state of nature and produce
hybrids.  Many instances could be given:  thus Macgillivray relates how a
male blackbird and female thrush "fell in love with each other," and
produced offspring.  (17.  'History of Brit. Birds,' vol. ii. p. 92.)
Several years ago eighteen cases had been recorded of the occurrence in
Great Britain of hybrids between the black grouse and pheasant (18.
'Zoologist,' 1853-1854, p. 3946.); but most of these cases may perhaps be
accounted for by solitary birds not finding one of their own species to
pair with.  With other birds, as Mr. Jenner Weir has reason to believe,
hybrids are sometimes the result of the casual intercourse of birds
building in close proximity.  But these remarks do not apply to the many
recorded instances of tamed or domestic birds, belonging to distinct
species, which have become absolutely fascinated with each other, although
living with their own species.  Thus Waterton (19.  Waterton, 'Essays on
Nat. Hist.' 2nd series, pp. 42 and 117.  For the following statements see
on the wigeon, 'Loudon's Mag. of Nat. Hist.' vol. ix. p. 616; L. Lloyd,
'Scandinavian Adventures,' vol. i. 1854, p. 452.  Dixon, 'Ornamental and
Domestic Poultry,' p. 137; Hewitt, in 'Journal of Horticulture,' Jan. 13,
1863, p. 40; Bechstein, 'Stubenvoegel,' 1840, s. 230.  Mr. J. Jenner Weir
has lately given me an analogous case with ducks of two species.) states
that out of a flock of twenty-three Canada geese, a female paired with a
solitary Bernicle gander, although so different in appearance and size; and
they produced hybrid offspring.  A male wigeon (Mareca penelope), living
with females of the same species, has been known to pair with a pintail
duck, Querquedula acuta.  Lloyd describes the remarkable attachment between
a shield-drake (Tadorna vulpanser) and a common duck.  Many additional
instances could be given; and the Rev. E.S. Dixon remarks that "those who
have kept many different species of geese together well know what
unaccountable attachments they are frequently forming, and that they are
quite as likely to pair and rear young with individuals of a race (species)
apparently the most alien to themselves as with their own stock."

The Rev. W.D. Fox informs me that he possessed at the same time a pair of
Chinese geese (Anser cygnoides), and a common gander with three geese.  The
two lots kept quite separate, until the Chinese gander seduced one of the
common geese to live with him.  Moreover, of the young birds hatched from
the eggs of the common geese, only four were pure, the other eighteen
proving hybrids; so that the Chinese gander seems to have had prepotent
charms over the common gander.  I will give only one other case; Mr. Hewitt
states that a wild duck, reared in captivity, "after breeding a couple of
seasons with her own mallard, at once shook him off on my placing a male
Pintail on the water.  It was evidently a case of love at first sight, for
she swam about the new-comer caressingly, though he appeared evidently
alarmed and averse to her overtures of affection.  From that hour she
forgot her old partner.  Winter passed by, and the next spring the pintail
seemed to have become a convert to her blandishments, for they nested and
produced seven or eight young ones."

What the charm may have been in these several cases, beyond mere novelty,
we cannot even conjecture.  Colour, however, sometimes comes into play; for
in order to raise hybrids from the siskin (Fringilla spinus) and the
canary, it is much the best plan, according to Bechstein, to place birds of
the same tint together.  Mr. Jenner Weir turned a female canary into his
aviary, where there were male linnets, goldfinches, siskins, greenfinches,
chaffinches, and other birds, in order to see which she would choose; but
there never was any doubt, and the greenfinch carried the day.  They paired
and produced hybrid offspring.

The fact of the female preferring to pair with one male rather than with
another of the same species is not so likely to excite attention, as when
this occurs, as we have just seen, between distinct species.  The former
cases can best be observed with domesticated or confined birds; but these
are often pampered by high feeding, and sometimes have their instincts
vitiated to an extreme degree.  Of this latter fact I could give sufficient
proofs with pigeons, and especially with fowls, but they cannot be here
related.  Vitiated instincts may also account for some of the hybrid unions
above mentioned; but in many of these cases the birds were allowed to range
freely over large ponds, and there is no reason to suppose that they were
unnaturally stimulated by high feeding.

With respect to birds in a state of nature, the first and most obvious
supposition which will occur to every one is that the female at the proper
season accepts the first male whom she may encounter; but she has at least
the opportunity for exerting a choice, as she is almost invariably pursued
by many males.  Audubon--and we must remember that he spent a long life in
prowling about the forests of the United States and observing the birds--
does not doubt that the female deliberately chooses her mate; thus,
speaking of a woodpecker, he says the hen is followed by half-a-dozen gay
suitors, who continue performing strange antics, "until a marked preference
is shewn for one."  The female of the red-winged starling (Agelaeus
phoeniceus) is likewise pursued by several males, "until, becoming
fatigued, she alights, receives their addresses, and soon makes a choice."
He describes also how several male night-jars repeatedly plunge through the
air with astonishing rapidity, suddenly turning, and thus making a singular
noise; "but no sooner has the female made her choice than the other males
are driven away."  With one of the vultures (Cathartes aura) of the United
States, parties of eight, ten, or more males and females assemble on fallen
logs, "exhibiting the strongest desire to please mutually," and after many
caresses, each male leads off his partner on the wing.  Audubon likewise
carefully observed the wild flocks of Canada geese (Anser canadensis), and
gives a graphic description of their love-antics; he says that the birds
which had been previously mated "renewed their courtship as early as the
month of January, while the others would be contending or coquetting for
hours every day, until all seemed satisfied with the choice they had made,
after which, although they remained together, any person could easily
perceive that they were careful to keep in pairs.  I have observed also
that the older the birds the shorter were the preliminaries of their
courtship.  The bachelors and old maids whether in regret, or not caring to
be disturbed by the bustle, quietly moved aside and lay down at some
distance from the rest."  (20.  Audubon, 'Ornithological Biography,' vol.
i. pp. 191, 349; vol. ii. pp. 42, 275; vol. iii. p. 2.)  Many similar
statements with respect to other birds could be cited from this same
observer.

Turning now to domesticated and confined birds, I will commence by giving
what little I have learnt respecting the courtship of fowls.  I have
received long letters on this subject from Messrs. Hewitt and Tegetmeier,
and almost an essay from the late Mr. Brent.  It will be admitted by every
one that these gentlemen, so well known from their published works, are
careful and experienced observers.  They do not believe that the females
prefer certain males on account of the beauty of their plumage; but some
allowance must be made for the artificial state under which these birds
have long been kept.  Mr. Tegetmeier is convinced that a gamecock, though
disfigured by being dubbed and with his hackles trimmed, would be accepted
as readily as a male retaining all his natural ornaments.  Mr. Brent,
however, admits that the beauty of the male probably aids in exciting the
female; and her acquiescence is necessary.  Mr. Hewitt is convinced that
the union is by no means left to mere chance, for the female almost
invariably prefers the most vigorous, defiant, and mettlesome male; hence
it is almost useless, as he remarks, "to attempt true breeding if a game-
cock in good health and condition runs the locality, for almost every hen
on leaving the roosting-place will resort to the game-cock, even though
that bird may not actually drive away the male of her own variety."  Under
ordinary circumstances the males and females of the fowl seem to come to a
mutual understanding by means of certain gestures, described to me by Mr.
Brent.  But hens will often avoid the officious attentions of young males.
Old hens, and hens of a pugnacious disposition, as the same writer informs
me, dislike strange males, and will not yield until well beaten into
compliance.  Ferguson, however, describes how a quarrelsome hen was subdued
by the gentle courtship of a Shanghai cock.  (21.  'Rare and Prize
Poultry,' 1854, p. 27.)

There is reason to believe that pigeons of both sexes prefer pairing with
birds of the same breed; and dovecot-pigeons dislike all the highly
improved breeds.  (22.  'Variation of Animals and Plants under
Domestication,' vol. ii. p. 103.)  Mr. Harrison Weir has lately heard from
a trustworthy observer, who keeps blue pigeons, that these drive away all
other coloured varieties, such as white, red, and yellow; and from another
observer, that a female dun carrier could not, after repeated trials, be
matched with a black male, but immediately paired with a dun.  Again, Mr.
Tegetmeier had a female blue turbit that obstinately refused to pair with
two males of the same breed, which were successively shut up with her for
weeks; but on being let out she would have immediately accepted the first
blue dragon that offered.  As she was a valuable bird, she was then shut up
for many weeks with a silver (i.e., very pale blue) male, and at last mated
with him.  Nevertheless, as a general rule, colour appears to have little
influence on the pairing of pigeons.  Mr. Tegetmeier, at my request,
stained some of his birds with magenta, but they were not much noticed by
the others.

Female pigeons occasionally feel a strong antipathy towards certain males,
without any assignable cause.  Thus MM. Boitard and Corbie, whose
experience extended over forty-five years, state:  "Quand une femelle
eprouve de l'antipathie pour un male avec lequel on veut l'accoupler,
malgre tous les feux de l'amour, malgre l'alpiste et le chenevis dont on la
nourrit pour augmenter son ardeur, malgre un emprisonnement de six mois et
meme d'un an, elle refuse constamment ses caresses; les avances empressees,
les agaceries, les tournoiemens, les tendres roucoulemens, rien ne peut lui
plaire ni l'emouvoir; gonflee, boudeuse, blottie dans un coin de sa prison,
elle n'en sort que pour boire et manger, ou pour repousser avec une espece
de rage des caresses devenues trop pressantes."  (23.  Boitard and Corbie,
'Les Pigeons,' etc., 1824, p. 12.  Prosper Lucas ('Traite de l'Hered. Nat.'
tom. ii. 1850, p. 296) has himself observed nearly similar facts with
pigeons.)  On the other hand, Mr. Harrison Weir has himself observed, and
has heard from several breeders, that a female pigeon will occasionally
take a strong fancy for a particular male, and will desert her own mate for
him.  Some females, according to another experienced observer, Riedel (24.
Die Taubenzucht, 1824, s. 86.), are of a profligate disposition, and prefer
almost any stranger to their own mate.  Some amorous males, called by our
English fanciers "gay birds," are so successful in their gallantries, that,
as Mr. H. Weir informs me, they must be shut up on account of the mischief
which they cause.

Wild turkeys in the United States, according to Audubon, "sometimes pay
their addresses to the domesticated females, and are generally received by
them with great pleasure."  So that these females apparently prefer the
wild to their own males.  (25.  'Ornithological Biography,' vol. i. p. 13.
See to the same effect, Dr. Bryant, in Allen's 'Mammals and Birds of
Florida,' p. 344.)

Here is a more curious case.  Sir R. Heron during many years kept an
account of the habits of the peafowl, which he bred in large numbers.  He
states that "the hens have frequently great preference to a particular
peafowl.  They were all so fond of an old pied cock, that one year, when he
was confined, though still in view, they were constantly assembled close to
the trellice-walls of his prison, and would not suffer a japanned peacock
to touch them.  On his being let out in the autumn, the oldest of the hens
instantly courted him and was successful in her courtship.  The next year
he was shut up in a stable, and then the hens all courted his rival."  (26.
'Proceedings, Zoological Society,' 1835, p. 54.  The japanned peacock is
considered by Mr. Sclater as a distinct species, and has been named Pavo
nigripennis; but the evidence seems to me to show that it is only a
variety.)  This rival was a japanned or black-winged peacock, to our eyes a
more beautiful bird than the common kind.

Lichtenstein, who was a good observer and had excellent opportunities of
observation at the Cape of Good Hope, assured Rudolphi that the female
widow-bird (Chera progne) disowns the male when robbed of the long tail-
feathers with which he is ornamented during the breeding-season.  I presume
that this observation must have been made on birds under confinement.  (27.
Rudolphi, 'Beitraege zur Anthropologie,' 1812, s. 184.)  Here is an
analogous case; Dr. Jaeger (28.  'Die Darwin'sche Theorie, und ihre
Stellung zu Moral und Religion,' 1869, s. 59.), director of the Zoological
Gardens of Vienna, states that a male silver-pheasant, who had been
triumphant over all other males and was the accepted lover of the females,
had his ornamental plumage spoiled.  He was then immediately superseded by
a rival, who got the upper hand and afterwards led the flock.

It is a remarkable fact, as shewing how important colour is in the
courtship of birds, that Mr. Boardman, a well-known collector and observer
of birds for many years in the Northern United States, has never in his
large experience seen an albino paired with another bird; yet he has had
opportunities of observing many albinos belonging to several species.  (29.
This statement is given by Mr. A. Leith Adams, in his 'Field and Forest
Rambles,' 1873, p. 76, and accords with his own experience.)  It can hardly
be maintained that albinos in a state of nature are incapable of breeding,
as they can be raised with the greatest facility under confinement.  It
appears, therefore, that we must attribute the fact that they do not pair
to their rejection by their normally coloured comrades.

Female birds not only exert a choice, but in some few cases they court the
male, or even fight together for his possession.  Sir R. Heron states that
with peafowl, the first advances are always made by the female; something
of the same kind takes place, according to Audubon, with the older females
of the wild turkey.  With the capercailzie, the females flit round the male
whilst he is parading at one of the places of assemblage, and solicit his
attention.  (30.  In regard to peafowl, see Sir R. Heron, 'Proc. Zoolog.
Soc.' 1835, p. 54, and the Rev. E.S. Dixon, 'Ornamental Poultry,' 1848, p.
8.  For the turkey, Audubon, ibid. p. 4.  For the capercailzie, Lloyd,
'Game Birds of Sweden,' 1867, p. 23.)  We have seen that a tame wild-duck
seduced an unwilling pintail drake after a long courtship.  Mr. Bartlett
believes that the Lophophorus, like many other gallinaceous birds, is
naturally polygamous, but two females cannot be placed in the same cage
with a male, as they fight so much together.  The following instance of
rivalry is more surprising as it relates to bullfinches, which usually pair
for life.  Mr. Jenner Weir introduced a dull-coloured and ugly female into
his aviary, and she immediately attacked another mated female so
unmercifully that the latter had to be separated.  The new female did all
the courtship, and was at last successful, for she paired with the male;
but after a time she met with a just retribution, for, ceasing to be
pugnacious, she was replaced by the old female, and the male then deserted
his new and returned to his old love.

In all ordinary cases the male is so eager that he will accept any female,
and does not, as far as we can judge, prefer one to the other; but, as we
shall hereafter see, exceptions to this rule apparently occur in some few
groups.  With domesticated birds, I have heard of only one case of males
shewing any preference for certain females, namely, that of the domestic
cock, who, according to the high authority of Mr. Hewitt, prefers the
younger to the older hens.  On the other hand, in effecting hybrid unions
between the male pheasant and common hens, Mr. Hewitt is convinced that the
pheasant invariably prefers the older birds.  He does not appear to be in
the least influenced by their colour; but "is most capricious in his
attachments" (31.  Mr. Hewitt, quoted in Tegetmeier's 'Poultry Book,' 1866,
p. 165.):  from some inexplicable cause he shews the most determined
aversion to certain hens, which no care on the part of the breeder can
overcome.  Mr. Hewitt informs me that some hens are quite unattractive even
to the males of their own species, so that they may be kept with several
cocks during a whole season, and not one egg out of forty or fifty will
prove fertile.  On the other hand, with the long-tailed duck (Harelda
glacialis), "it has been remarked," says M. Ekstrom, "that certain females
are much more courted than the rest.  Frequently, indeed, one sees an
individual surrounded by six or eight amorous males."  Whether this
statement is credible, I know not; but the native sportsmen shoot these
females in order to stuff them as decoys.  (32.  Quoted in Lloyd's 'Game
Birds of Sweden,' p. 345.)

With respect to female birds feeling a preference for particular males, we
must bear in mind that we can judge of choice being exerted only by
analogy.  If an inhabitant of another planet were to behold a number of
young rustics at a fair courting a pretty girl, and quarrelling about her
like birds at one of their places of assemblage, he would, by the eagerness
of the wooers to please her and to display their finery, infer that she had
the power of choice.  Now with birds the evidence stands thus:  they have
acute powers of observation, and they seem to have some taste for the
beautiful both in colour and sound.  It is certain that the females
occasionally exhibit, from unknown causes, the strongest antipathies and
preferences for particular males.  When the sexes differ in colour or in
other ornaments the males with rare exceptions are the more decorated,
either permanently or temporarily during the breeding-season.  They
sedulously display their various ornaments, exert their voices, and perform
strange antics in the presence of the females.  Even well-armed males, who,
it might be thought, would altogether depend for success on the law of
battle, are in most cases highly ornamented; and their ornaments have been
acquired at the expense of some loss of power.  In other cases ornaments
have been acquired, at the cost of increased risk from birds and beasts of
prey.  With various species many individuals of both sexes congregate at
the same spot, and their courtship is a prolonged affair.  There is even
reason to suspect that the males and females within the same district do
not always succeed in pleasing each other and pairing.

What then are we to conclude from these facts and considerations?  Does the
male parade his charms with so much pomp and rivalry for no purpose?  Are
we not justified in believing that the female exerts a choice, and that she
receives the addresses of the male who pleases her most?  It is not
probable that she consciously deliberates; but she is most excited or
attracted by the most beautiful, or melodious, or gallant males.  Nor need
it be supposed that the female studies each stripe or spot of colour; that
the peahen, for instance, admires each detail in the gorgeous train of the
peacock--she is probably struck only by the general effect.  Nevertheless,
after hearing how carefully the male Argus pheasant displays his elegant
primary wing-feathers, and erects his ocellated plumes in the right
position for their full effect; or again, how the male goldfinch
alternately displays his gold-bespangled wings, we ought not to feel too
sure that the female does not attend to each detail of beauty.  We can
judge, as already remarked, of choice being exerted, only from analogy; and
the mental powers of birds do not differ fundamentally from ours.  From
these various considerations we may conclude that the pairing of birds is
not left to chance; but that those males, which are best able by their
various charms to please or excite the female, are under ordinary
circumstances accepted.  If this be admitted, there is not much difficulty
in understanding how male birds have gradually acquired their ornamental
characters.  All animals present individual differences, and as man can
modify his domesticated birds by selecting the individuals which appear to
him the most beautiful, so the habitual or even occasional preference by
the female of the more attractive males would almost certainly lead to
their modification; and such modifications might in the course of time be
augmented to almost any extent, compatible with the existence of the
species.

VARIABILITY OF BIRDS, AND ESPECIALLY OF THEIR SECONDARY SEXUAL CHARACTERS.

Variability and inheritance are the foundations for the work of selection.
That domesticated birds have varied greatly, their variations being
inherited, is certain.  That birds in a state of nature have been modified
into distinct races is now universally admitted.  (33.  According to Dr.
Blasius ('Ibis,' vol. ii. 1860, p. 297), there are 425 indubitable species
of birds which breed in Europe, besides sixty forms, which are frequently
regarded as distinct species.  Of the latter, Blasius thinks that only ten
are really doubtful, and that the other fifty ought to be united with their
nearest allies; but this shews that there must be a considerable amount of
variation with some of our European birds.  It is also an unsettled point
with naturalists, whether several North American birds ought to be ranked
as specifically distinct from the corresponding European species.  So again
many North American forms which until lately were named as distinct
species, are now considered to be local races.)  Variations may be divided
into two classes; those which appear to our ignorance to arise
spontaneously, and those which are directly related to the surrounding
conditions, so that all or nearly all the individuals of the same species
are similarly modified.  Cases of the latter kind have recently been
observed with care by Mr. J.A. Allen (34.  'Mammals and Birds of East
Florida,' also an 'Ornithological Reconnaissance of Kansas,' etc.
Notwithstanding the influence of climate on the colours of birds, it is
difficult to account for the dull or dark tints of almost all the species
inhabiting certain countries, for instance, the Galapagos Islands under the
equator, the wide temperate plains of Patagonia, and, as it appears, Egypt
(see Mr. Hartshorne in the 'American Naturalist,' 1873, p. 747).  These
countries are open, and afford little shelter to birds; but it seems
doubtful whether the absence of brightly coloured species can be explained
on the principle of protection, for on the Pampas, which are equally open,
though covered by green grass, and where the birds would be equally exposed
to danger, many brilliant and conspicuously coloured species are common.  I
have sometimes speculated whether the prevailing dull tints of the scenery
in the above named countries may not have affected the appreciation of
bright colours by the birds inhabiting them.), who shews that in the United
States many species of birds gradually become more strongly coloured in
proceeding southward, and more lightly coloured in proceeding westward to
the arid plains of the interior.  Both sexes seem generally to be affected
in a like manner, but sometimes one sex more than the other.  This result
is not incompatible with the belief that the colours of birds are mainly
due to the accumulation of successive variations through sexual selection;
for even after the sexes have been greatly differentiated, climate might
produce an equal effect on both sexes, or a greater effect on one sex than
on the other, owing to some constitutional difference.

Individual differences between the members of the same species are admitted
by every one to occur under a state of nature.  Sudden and strongly marked
variations are rare; it is also doubtful whether if beneficial they would
often be preserved through selection and transmitted to succeeding
generations.  (35.  'Origin of Species' fifth edit. 1869, p.104.  I had
always perceived, that rare and strongly-marked deviations of structure,
deserving to be called monstrosities, could seldom be preserved through
natural selection, and that the preservation of even highly-beneficial
variations would depend to a certain extent on chance.  I had also fully
appreciated the importance of mere individual differences, and this led me
to insist so strongly on the importance of that unconscious form of
selection by man, which follows from the preservation of the most valued
individuals of each breed, without any intention on his part to modify the
characters of the breed.  But until I read an able article in the 'North
British Review' (March 1867, p. 289, et seq.), which has been of more use
to me than any other Review, I did not see how great the chances were
against the preservation of variations, whether slight or strongly
pronounced, occurring only in single individuals.)  Nevertheless, it may be
worth while to give the few cases which I have been able to collect,
relating chiefly to colour,--simple albinism and melanism being excluded.
Mr. Gould is well known to admit the existence of few varieties, for he
esteems very slight differences as specific; yet he states (36.
'Introduction to the Trochlidae,' p. 102.) that near Bogota certain
humming-birds belonging to the genus Cynanthus are divided into two or
three races or varieties, which differ from each other in the colouring of
the tail--"some having the whole of the feathers blue, while others have
the eight central ones tipped with beautiful green."  It does not appear
that intermediate gradations have been observed in this or the following
cases.  In the males alone of one of the Australian parrakeets "the thighs
in some are scarlet, in others grass-green."  In another parrakeet of the
same country "some individuals have the band across the wing-coverts
bright-yellow, while in others the same part is tinged with red."  (37.
Gould, 'Handbook to Birds of Australia,' vol. ii. pp. 32 and 68.)  In the
United States some few of the males of the scarlet tanager (Tanagra rubra)
have "a beautiful transverse band of glowing red on the smaller wing-
coverts" (38.  Audubon, 'Ornithological Biography,' 1838, vol. iv. p.
389.); but this variation seems to be somewhat rare, so that its
preservation through sexual selection would follow only under usually
favourable circumstances.  In Bengal the Honey buzzard (Pernis cristata)
has either a small rudimental crest on its head, or none at all:  so slight
a difference, however, would not have been worth notice, had not this same
species possessed in Southern India a well-marked occipital crest formed of
several graduated feathers."  (39.  Jerdon, 'Birds of India,' vol. i. p.
108; and Mr. Blyth, in 'Land and Water,' 1868, p. 381.)

The following case is in some respects more interesting.  A pied variety of
the raven, with the head, breast, abdomen, and parts of the wings and tail-
feathers white, is confined to the Feroe Islands.  It is not very rare
there, for Graba saw during his visit from eight to ten living specimens.
Although the characters of this variety are not quite constant, yet it has
been named by several distinguished ornithologists as a distinct species.
The fact of the pied birds being pursued and persecuted with much clamour
by the other ravens of the island was the chief cause which led Brunnich to
conclude that they were specifically distinct; but this is now known to be
an error.  (40.  Graba, 'Tagebuch Reise nach Faro,' 1830, ss. 51-54.
Macgillivray, 'History of British Birds,' vol. iii. p. 745, 'Ibis,' vol. v.
1863, p. 469.)  This case seems analogous to that lately given of albino
birds not pairing from being rejected by their comrades.

In various parts of the northern seas a remarkable variety of the common
Guillemot (Uria troile) is found; and in Feroe, one out of every five
birds, according to Graba's estimation, presents this variation.  It is
characterised (41.  Graba, ibid. s. 54.  Macgillivray, ibid. vol. v. p.
327.) by a pure white ring round the eye, with a curved narrow white line,
an inch and a half in length, extending back from the ring.  This
conspicuous character has caused the bird to be ranked by several
ornithologists as a distinct species under the name of U. lacrymans, but it
is now known to be merely a variety.  It often pairs with the common kind,
yet intermediate gradations have never been seen; nor is this surprising,
for variations which appear suddenly, are often, as I have elsewhere shewn
(42.  'Variation of Animals and Plants under Domestication,' vol. ii. p.
92.), transmitted either unaltered or not at all.  We thus see that two
distinct forms of the same species may co-exist in the same district, and
we cannot doubt that if the one had possessed any advantage over the other,
it would soon have been multiplied to the exclusion of the latter.  If, for
instance, the male pied ravens, instead of being persecuted by their
comrades, had been highly attractive (like the above pied peacock) to the
black female ravens their numbers would have rapidly increased.  And this
would have been a case of sexual selection.

With respect to the slight individual differences which are common, in a
greater or less degree, to all the members of the same species, we have
every reason to believe that they are by far the most important for the
work of selection.  Secondary sexual characters are eminently liable to
vary, both with animals in a state of nature and under domestication.  (43.
On these points see also 'Variation of Animals and Plants under
Domestication,' vol. i. p. 253; vol ii. pp. 73, 75.)  There is also reason
to believe, as we have seen in our eighth chapter, that variations are more
apt to occur in the male than in the female sex.  All these contingencies
are highly favourable for sexual selection.  Whether characters thus
acquired are transmitted to one sex or to both sexes, depends, as we shall
see in the following chapter, on the form of inheritance which prevails.

It is sometimes difficult to form an opinion whether certain slight
differences between the sexes of birds are simply the result of variability
with sexually-limited inheritance, without the aid of sexual selection, or
whether they have been augmented through this latter process.  I do not
here refer to the many instances where the male displays splendid colours
or other ornaments, of which the female partakes to a slight degree; for
these are almost certainly due to characters primarily acquired by the male
having been more or less transferred to the female.  But what are we to
conclude with respect to certain birds in which, for instance, the eyes
differ slightly in colour in the two sexes?  (44.  See, for instance, on
the irides of a Podica and Gallicrex in 'Ibis,' vol. ii. 1860, p. 206; and
vol. v. 1863, p. 426.)  In some cases the eyes differ conspicuously; thus
with the storks of the genus Xenorhynchus, those of the male are blackish-
hazel, whilst those of the females are gamboge-yellow; with many hornbills
(Buceros), as I hear from Mr. Blyth (45.  See also Jerdon, 'Birds of
India,' vol. i. pp. 243-245.), the males have intense crimson eyes, and
those of the females are white.  In the Buceros bicornis, the hind margin
of the casque and a stripe on the crest of the beak are black in the male,
but not so in the female.  Are we to suppose that these black marks and the
crimson colour of the eyes have been preserved or augmented through sexual
selection in the males?  This is very doubtful; for Mr. Bartlett shewed me
in the Zoological Gardens that the inside of the mouth of this Buceros is
black in the male and flesh-coloured in the female; and their external
appearance or beauty would not be thus affected.  I observed in Chile (46.
'Zoology of the Voyage of H.M.S. "Beagle,"' 1841, p. 6.) that the iris in
the condor, when about a year old, is dark-brown, but changes at maturity
into yellowish-brown in the male, and into bright red in the female.  The
male has also a small, longitudinal, leaden-coloured, fleshy crest or comb.
The comb of many gallinaceous birds is highly ornamental, and assumes vivid
colours during the act of courtship; but what are we to think of the dull-
coloured comb of the condor, which does not appear to us in the least
ornamental?  The same question may be asked in regard to various other
characters, such as the knob on the base of the beak of the Chinese goose
(Anser cygnoides), which is much larger in the male than in the female.  No
certain answer can be given to these questions; but we ought to be cautious
in assuming that knobs and various fleshy appendages cannot be attractive
to the female, when we remember that with savage races of man various
hideous deformities--deep scars on the face with the flesh raised into
protuberances, the septum of the nose pierced by sticks or bones, holes in
the ears and lips stretched widely open--are all admired as ornamental.

Whether or not unimportant differences between the sexes, such as those
just specified, have been preserved through sexual selection, these
differences, as well as all others, must primarily depend on the laws of
variation.  On the principle of correlated development, the plumage often
varies on different parts of the body, or over the whole body, in the same
manner.  We see this well illustrated in certain breeds of the fowl.  In
all the breeds the feathers on the neck and loins of the males are
elongated, and are called hackles; now when both sexes acquire a top-knot,
which is a new character in the genus, the feathers on the head of the male
become hackle-shaped, evidently on the principle of correlation; whilst
those on the head of the female are of the ordinary shape.  The colour also
of the hackles forming the top-knot of the male, is often correlated with
that of the hackles on the neck and loins, as may be seen by comparing
these feathers in the golden and silver-spangled Polish, the Houdans, and
Creve-coeur breeds.  In some natural species we may observe exactly the
same correlation in the colours of these same feathers, as in the males of
the splendid Gold and Amherst pheasants.

The structure of each individual feather generally causes any change in its
colouring to be symmetrical; we see this in the various laced, spangled,
and pencilled breeds of the fowl; and on the principle of correlation the
feathers over the whole body are often coloured in the same manner.  We are
thus enabled without much trouble to rear breeds with their plumage marked
almost as symmetrically as in natural species.  In laced and spangled fowls
the coloured margins of the feathers are abruptly defined; but in a mongrel
raised by me from a black Spanish cock glossed with green, and a white
game-hen, all the feathers were greenish-black, excepting towards their
extremities, which were yellowish-white; but between the white extremities
and the black bases, there was on each feather a symmetrical, curved zone
of dark-brown.  In some instances the shaft of the feather determines the
distribution of the tints; thus with the body-feathers of a mongrel from
the same black Spanish cock and a silver-spangled Polish hen, the shaft,
together with a narrow space on each side, was greenish-black, and this was
surrounded by a regular zone of dark-brown, edged with brownish-white.  In
these cases we have feathers symmetrically shaded, like those which give so
much elegance to the plumage of many natural species.  I have also noticed
a variety of the common pigeon with the wing-bars symmetrically zoned with
three bright shades, instead of being simply black on a slaty-blue ground,
as in the parent-species.

In many groups of birds the plumage is differently coloured in the several
species, yet certain spots, marks, or stripes are retained by all.
Analogous cases occur with the breeds of the pigeon, which usually retain
the two wing-bars, though they may be coloured red, yellow, white, black,
or blue, the rest of the plumage being of some wholly different tint.  Here
is a more curious case, in which certain marks are retained, though
coloured in a manner almost exactly the opposite of what is natural; the
aboriginal pigeon has a blue tail, with the terminal halves of the outer
webs of the two outer tail feathers white; now there is a sub-variety
having a white instead of a blue tail, with precisely that part black which
is white in the parent-species.  (47.  Bechstein, 'Naturgeschichte
Deutschlands,' B. iv. 1795, s. 31, on a sub-variety of the Monck pigeon.)

FORMATION AND VARIABILITY OF THE OCELLI OR EYE-LIKE SPOTS ON THE PLUMAGE OF
BIRDS.

[Fig. 53.  Cyllo leda, Linn., from a drawing by Mr. Trimen, shewing the
extreme range of variation in the ocelli.
A.  Specimen, from Mauritius, upper surface of fore-wing.
A1.  Specimen, from Natal, ditto.
B.  Specimen, from Java, upper surface of hind-wing.
B1.  Specimen, from Mauritius, ditto.]

As no ornaments are more beautiful than the ocelli on the feathers of
various birds, on the hairy coats of some mammals, on the scales of
reptiles and fishes, on the skin of amphibians, on the wings of many
Lepidoptera and other insects, they deserve to be especially noticed.  An
ocellus consists of a spot within a ring of another colour, like the pupil
within the iris, but the central spot is often surrounded by additional
concentric zones.  The ocelli on the tail-coverts of the peacock offer a
familiar example, as well as those on the wings of the peacock-butterfly
(Vanessa).  Mr. Trimen has given me a description of a S. African moth
(Gynanisa isis), allied to our Emperor moth, in which a magnificent ocellus
occupies nearly the whole surface of each hinder wing; it consists of a
black centre, including a semi-transparent crescent-shaped mark, surrounded
by successive, ochre-yellow, black, ochre-yellow, pink, white, pink, brown,
and whitish zones.  Although we do not know the steps by which these
wonderfully beautiful and complex ornaments have been developed, the
process has probably been a simple one, at least with insects; for, as Mr.
Trimen writes to me, "no characters of mere marking or coloration are so
unstable in the Lepidoptera as the ocelli, both in number and size."  Mr.
Wallace, who first called my attention to this subject, shewed me a series
of specimens of our common meadow-brown butterfly (Hipparchia janira)
exhibiting numerous gradations from a simple minute black spot to an
elegantly-shaded ocellus.  In a S. African butterfly (Cyllo leda, Linn.),
belonging to the same family, the ocelli are even still more variable.  In
some specimens (A, Fig. 53) large spaces on the upper surface of the wings
are coloured black, and include irregular white marks; and from this state
a complete gradation can be traced into a tolerably perfect ocellus (A1),
and this results from the contraction of the irregular blotches of colour.
In another series of specimens a gradation can be followed from excessively
minute white dots, surrounded by a scarcely visible black line (B), into
perfectly symmetrical and large ocelli (B1).  (48.  This woodcut has been
engraved from a beautiful drawing, most kindly made for me by Mr. Trimen;
see also his description of the wonderful amount of variation in the
coloration and shape of the wings of this butterfly, in his 'Rhopalocera
Africae Australis,' p. 186.)  In cases like these, the development of a
perfect ocellus does not require a long course of variation and selection.

With birds and many other animals, it seems to follow from the comparison
of allied species that circular spots are often generated by the breaking
up and contraction of stripes.  In the Tragopan pheasant faint white lines
in the female represent the beautiful white spots in the male (49.  Jerdon,
'Birds of India,' vol. iii. p. 517.); and something of the same kind may be
observed in the two sexes of the Argus pheasant.  However this may be,
appearances strongly favour the belief that on the one hand, a dark spot is
often formed by the colouring matter being drawn towards a central point
from a surrounding zone, which latter is thus rendered lighter; and, on the
other hand, that a white spot is often formed by the colour being driven
away from a central point, so that it accumulates in a surrounding darker
zone.  In either case an ocellus is the result.  The colouring matter seems
to be a nearly constant quantity, but is redistributed, either
centripetally or centrifugally.  The feathers of the common guinea-fowl
offer a good instance of white spots surrounded by darker zones; and
wherever the white spots are large and stand near each other, the
surrounding dark zones become confluent.  In the same wing-feather of the
Argus pheasant dark spots may be seen surrounded by a pale zone, and white
spots by a dark zone.  Thus the formation of an ocellus in its most
elementary state appears to be a simple affair.  By what further steps the
more complex ocelli, which are surrounded by many successive zones of
colour, have been generated, I will not pretend to say.  But the zoned
feathers of the mongrels from differently coloured fowls, and the
extraordinary variability of the ocelli on many Lepidoptera, lead us to
conclude that their formation is not a complex process, but depends on some
slight and graduated change in the nature of the adjoining tissues.

GRADATION OF SECONDARY SEXUAL CHARACTERS.

[Fig. 54.  Feather of Peacock, about two-thirds of natural size, drawn by
Mr. Ford.  The transparent zone is represented by the outermost white zone,
confined to the upper end of the disc.]

Cases of gradation are important, as shewing us that highly complex
ornaments may be acquired by small successive steps.  In order to discover
the actual steps by which the male of any existing bird has acquired his
magnificent colours or other ornaments, we ought to behold the long line of
his extinct progenitors; but this is obviously impossible.  We may,
however, generally gain a clue by comparing all the species of the same
group, if it be a large one; for some of them will probably retain, at
least partially, traces of their former characters.  Instead of entering on
tedious details respecting various groups, in which striking instances of
gradation could be given, it seems the best plan to take one or two
strongly marked cases, for instance that of the peacock, in order to see if
light can be thrown on the steps by which this bird has become so
splendidly decorated.  The peacock is chiefly remarkable from the
extraordinary length of his tail-coverts; the tail itself not being much
elongated.  The barbs along nearly the whole length of these feathers stand
separate or are decomposed; but this is the case with the feathers of many
species, and with some varieties of the domestic fowl and pigeon.  The
barbs coalesce towards the extremity of the shaft forming the oval disc or
ocellus, which is certainly one of the most beautiful objects in the world.
It consists of an iridescent, intensely blue, indented centre, surrounded
by a rich green zone, this by a broad coppery-brown zone, and this by five
other narrow zones of slightly different iridescent shades.  A trifling
character in the disc deserves notice; the barbs, for a space along one of
the concentric zones are more or less destitute of their barbules, so that
a part of the disc is surrounded by an almost transparent zone, which gives
it a highly finished aspect.  But I have elsewhere described (50.
'Variation of Animals and Plants under Domestication,' vol. i. p. 254.) an
exactly analogous variation in the hackles of a sub-variety of the game-
cock, in which the tips, having a metallic lustre, "are separated from the
lower part of the feather by a symmetrically shaped transparent zone,
composed of the naked portions of the barbs."  The lower margin or base of
the dark-blue centre of the ocellus is deeply indented on the line of the
shaft.  The surrounding zones likewise shew traces, as may be seen in the
drawing (Fig. 54), of indentations, or rather breaks.  These indentations
are common to the Indian and Javan peacocks (Pavo cristatus and P.
muticus); and they seem to deserve particular attention, as probably
connected with the development of the ocellus; but for a long time I could
not conjecture their meaning.

If we admit the principle of gradual evolution, there must formerly have
existed many species which presented every successive step between the
wonderfully elongated tail-coverts of the peacock and the short tail-
coverts of all ordinary birds; and again between the magnificent ocelli of
the former, and the simpler ocelli or mere coloured spots on other birds;
and so with all the other characters of the peacock.  Let us look to the
allied Gallinaceae for any still-existing gradations.  The species and sub-
species of Polyplectron inhabit countries adjacent to the native land of
the peacock; and they so far resemble this bird that they are sometimes
called peacock-pheasants.  I am also informed by Mr. Bartlett that they
resemble the peacock in their voice and in some of their habits.  During
the spring the males, as previously described, strut about before the
comparatively plain-coloured females, expanding and erecting their tail and
wing-feathers, which are ornamented with numerous ocelli.  I request the
reader to turn back to the drawing (Fig. 51) of a Polyplectron; In P.
napoleonis the ocelli are confined to the tail, and the back is of a rich
metallic blue; in which respects this species approaches the Java peacock.
P. hardwickii possesses a peculiar top-knot, which is also somewhat like
that of the Java peacock.  In all the species the ocelli on the wings and
tail are either circular or oval, and consist of a beautiful, iridescent,
greenish-blue or greenish-purple disc, with a black border.  This border in
P. chinquis shades into brown, edged with cream colour, so that the ocellus
is here surrounded with variously shaded, though not bright, concentric
zones.  The unusual length of the tail-coverts is another remarkable
character in Polyplectron; for in some of the species they are half, and in
others two-thirds as long as the true tail-feathers.  The tail-coverts are
ocellated as in the peacock.  Thus the several species of Polyplectron
manifestly make a graduated approach to the peacock in the length of their
tail-coverts, in the zoning of the ocelli, and in some other characters.

[Fig. 55.  Part of a tail-covert of Polyplectron chinquis, with the two
ocelli of natural size.

Fig. 56.  Part of a tail-covert of Polyplectron malaccense, with the two
ocelli, partially confluent, of natural size.]

Notwithstanding this approach, the first species of Polyplectron which I
examined almost made me give up the search; for I found not only that the
true tail-feathers, which in the peacock are quite plain, were ornamented
with ocelli, but that the ocelli on all the feathers differed fundamentally
from those of the peacock, in there being two on the same feather (Fig.
55), one on each side of the shaft.  Hence I concluded that the early
progenitors of the peacock could not have resembled a Polyplectron.  But on
continuing my search, I observed that in some of the species the two ocelli
stood very near each other; that in the tail-feathers of P. hardwickii they
touched each other; and, finally, that on the tail-coverts of this same
species as well as of P. malaccense (Fig. 56) they were actually confluent.
As the central part alone is confluent, an indentation is left at both the
upper and lower ends; and the surrounding coloured zones are likewise
indented.  A single ocellus is thus formed on each tail-covert, though
still plainly betraying its double origin.  These confluent ocelli differ
from the single ocelli of the peacock in having an indentation at both
ends, instead of only at the lower or basal end.  The explanation, however,
of this difference is not difficult; in some species of Polyplectron the
two oval ocelli on the same feather stand parallel to each other; in other
species (as in P. chinquis) they converge towards one end; now the partial
confluence of two convergent ocelli would manifestly leave a much deeper
indentation at the divergent than at the convergent end.  It is also
manifest that if the convergence were strongly pronounced and the
confluence complete, the indentation at the convergent end would tend to
disappear.

The tail-feathers in both species of the peacock are entirely destitute of
ocelli, and this apparently is related to their being covered up and
concealed by the long tail-coverts.  In this respect they differ remarkably
from the tail-feathers of Polyplectron, which in most of the species are
ornamented with larger ocelli than those on the tail-coverts.  Hence I was
led carefully to examine the tail-feathers of the several species, in order
to discover whether their ocelli shewed any tendency to disappear; and to
my great satisfaction, this appeared to be so.  The central tail-feathers
of P. napoleonis have the two ocelli on each side of the shaft perfectly
developed; but the inner ocellus becomes less and less conspicuous on the
more exterior tail-feathers, until a mere shadow or rudiment is left on the
inner side of the outermost feather.  Again, in P. malaccense, the ocelli
on the tail-coverts are, as we have seen, confluent; and these feathers are
of unusual length, being two-thirds of the length of the tail-feathers, so
that in both these respects they approach the tail-coverts of the peacock.
Now in P. malaccense, the two central tail-feathers alone are ornamented,
each with two brightly-coloured ocelli, the inner ocellus having completely
disappeared from all the other tail-feathers.  Consequently the tail-
coverts and tail-feathers of this species of Polyplectron make a near
approach in structure and ornamentation to the corresponding feathers of
the peacock.

As far, then, as gradation throws light on the steps by which the
magnificent train of the peacock has been acquired, hardly anything more is
needed.  If we picture to ourselves a progenitor of the peacock in an
almost exactly intermediate condition between the existing peacock, with
his enormously elongated tail-coverts, ornamented with single ocelli, and
an ordinary gallinaceous bird with short tail-coverts, merely spotted with
some colour, we shall see a bird allied to Polyplectron--that is, with
tail-coverts, capable of erection and expansion, ornamented with two
partially confluent ocelli, and long enough almost to conceal the tail-
feathers, the latter having already partially lost their ocelli.  The
indentation of the central disc and of the surrounding zones of the
ocellus, in both species of peacock, speaks plainly in favour of this view,
and is otherwise inexplicable.  The males of Polyplectron are no doubt
beautiful birds, but their beauty, when viewed from a little distance,
cannot be compared with that of the peacock.  Many female progenitors of
the peacock must, during a long line of descent, have appreciated this
superiority; for they have unconsciously, by the continued preference for
the most beautiful males, rendered the peacock the most splendid of living
birds.

ARGUS PHEASANT.

Another excellent case for investigation is offered by the ocelli on the
wing-feathers of the Argus pheasant, which are shaded in so wonderful a
manner as to resemble balls lying loose within sockets, and consequently
differ from ordinary ocelli.  No one, I presume, will attribute the
shading, which has excited the admiration of many experienced artists, to
chance--to the fortuitous concourse of atoms of colouring matter.  That
these ornaments should have been formed through the selection of many
successive variations, not one of which was originally intended to produce
the ball-and-socket effect, seems as incredible as that one of Raphael's
Madonnas should have been formed by the selection of chance daubs of paint
made by a long succession of young artists, not one of whom intended at
first to draw the human figure.  In order to discover how the ocelli have
been developed, we cannot look to a long line of progenitors, nor to many
closely-allied forms, for such do not now exist.  But fortunately the
several feathers on the wing suffice to give us a clue to the problem, and
they prove to demonstration that a gradation is at least possible from a
mere spot to a finished ball-and-socket ocellus.

[Fig. 57.  Part of secondary wing-feather of Argus pheasant, shewing two
perfect ocelli, a and b.  A, B, C, D, etc., are dark stripes running
obliquely down, each to an ocellus.
[Much of the web on both sides, especially to the left of the shaft, has
been cut off.]

Fig.59.  Portion of one of the secondary wing-feathers near to the body,
shewing the so-called elliptic ornaments.  The right-hand figure is given
merely as a diagram for the sake of the letters of reference.
A, B, C, D, etc.  Rows of spots running down to and forming the elliptic
ornaments.
b.  Lowest spot or mark in row B.
c.  The next succeeding spot or mark in the same row.
d.  Apparently a broken prolongation of the spot c. in the same row B.]

The wing-feathers, bearing the ocelli, are covered with dark stripes (Fig.
57) or with rows of dark spots (Fig. 59), each stripe or row of spots
running obliquely down the outer side of the shaft to one of the ocelli.
The spots are generally elongated in a line transverse to the row in which
they stand.  They often become confluent either in the line of the row--and
then they form a longitudinal stripe--or transversely, that is, with the
spots in the adjoining rows, and then they form transverse stripes.  A spot
sometimes breaks up into smaller spots, which still stand in their proper
places.

It will be convenient first to describe a perfect ball-and-socket ocellus.
This consists of an intensely black circular ring, surrounding a space
shaded so as exactly to resemble a ball.  The figure here given has been
admirably drawn by Mr. Ford and well engraved, but a woodcut cannot exhibit
the exquisite shading of the original.  The ring is almost always slightly
broken or interrupted (Fig. 57) at a point in the upper half, a little to
the right of and above the white shade on the enclosed ball; it is also
sometimes broken towards the base on the right hand.  These little breaks
have an important meaning.  The ring is always much thickened, with the
edges ill-defined towards the left-hand upper corner, the feather being
held erect, in the position in which it is here drawn.  Beneath this
thickened part there is on the surface of the ball an oblique almost pure-
white mark, which shades off downwards into a pale-leaden hue, and this
into yellowish and brown tints, which insensibly become darker and darker
towards the lower part of the ball.  It is this shading which gives so
admirably the effect of light shining on a convex surface.  If one of the
balls be examined, it will be seen that the lower part is of a brown tint
and is indistinctly separated by a curved oblique line from the upper part,
which is yellower and more leaden; this curved oblique line runs at right
angles to the longer axis of the white patch of light, and indeed of all
the shading; but this difference in colour, which cannot of course be shewn
in the woodcut, does not in the least interfere with the perfect shading of
the ball.  It should be particularly observed that each ocellus stands in
obvious connection either with a dark stripe, or with a longitudinal row of
dark spots, for both occur indifferently on the same feather.  Thus in Fig.
57 stripe A runs to ocellus a; B runs to ocellus b; stripe C is broken in
the upper part, and runs down to the next succeeding ocellus, not
represented in the woodcut; D to the next lower one, and so with the
stripes E and F.  Lastly, the several ocelli are separated from each other
by a pale surface bearing irregular black marks.

[Fig. 58.  Basal part of the secondary wing feather, nearest to the body.]

I will next describe the other extreme of the series, namely, the first
trace of an ocellus.  The short secondary wing-feather (Fig. 58), nearest
to the body, is marked like the other feathers, with oblique, longitudinal,
rather irregular, rows of very dark spots.  The basal spot, or that nearest
the shaft, in the five lower rows (excluding the lowest one) is a little
larger than the other spots of the same row, and a little more elongated in
a transverse direction.  It differs also from the other spots by being
bordered on its upper side with some dull fulvous shading.  But this spot
is not in any way more remarkable than those on the plumage of many birds,
and might easily be overlooked.  The next higher spot does not differ at
all from the upper ones in the same row.  The larger basal spots occupy
exactly the same relative position on these feathers as do the perfect
ocelli on the longer wing-feathers.

By looking to the next two or three succeeding wing-feathers, an absolutely
insensible gradation can be traced from one of the last-described basal
spots, together with the next higher one in the same row, to a curious
ornament, which cannot be called an ocellus, and which I will name, from
the want of a better term, an "elliptic ornament."  These are shewn in the
accompanying figure (Fig. 59).  We here see several oblique rows, A, B, C,
D, etc. (see the lettered diagram on the right hand), of dark spots of the
usual character.  Each row of spots runs down to and is connected with one
of the elliptic ornaments, in exactly the same manner as each stripe in
Fig. 57 runs down to and is connected with one of the ball-and-socket
ocelli.  Looking to any one row, for instance, B, in Fig. 59, the lowest
mark (b) is thicker and considerably longer than the upper spots, and has
its left extremity pointed and curved upwards.  This black mark is abruptly
bordered on its upper side by a rather broad space of richly shaded tints,
beginning with a narrow brown zone, which passes into orange, and this into
a pale leaden tint, with the end towards the shaft much paler.  These
shaded tints together fill up the whole inner space of the elliptic
ornament.  The mark (b) corresponds in every respect with the basal shaded
spot of the simple feather described in the last paragraph (Fig. 58), but
is more highly developed and more brightly coloured.  Above and to the
right of this spot (b, Fig. 59), with its bright shading, there is a long
narrow, black mark (c), belonging to the same row, and which is arched a
little downwards so as to face (b).  This mark is sometimes broken into two
portions.  It is also narrowly edged on the lower side with a fulvous tint.
To the left of and above c, in the same oblique direction, but always more
or less distinct from it, there is another black mark (d).  This mark is
generally sub-triangular and irregular in shape, but in the one lettered in
the diagram it is unusually narrow, elongated, and regular.  It apparently
consists of a lateral and broken prolongation of the mark (c), together
with its confluence with a broken and prolonged part of the next spot
above; but I do not feel sure of this.  These three marks, b, c, and d,
with the intervening bright shades, form together the so-called elliptic
ornament.  These ornaments placed parallel to the shaft, manifestly
correspond in position with the ball-and-socket ocelli.  Their extremely
elegant appearance cannot be appreciated in the drawing, as the orange and
leaden tints, contrasting so well with the black marks, cannot be shewn.

[Fig. 60.  An ocellus in an intermediate condition between the elliptic
ornament and the perfect ball-and-socket ocellus.]

Between one of the elliptic ornaments and a perfect ball-and-socket
ocellus, the gradation is so perfect that it is scarcely possible to decide
when the latter term ought to be used.  The passage from the one into the
other is effected by the elongation and greater curvature in opposite
directions of the lower black mark (b, Fig. 59), and more especially of the
upper one (c), together with the contraction of the elongated sub-
triangular or narrow mark (d), so that at last these three marks become
confluent, forming an irregular elliptic ring.  This ring is gradually
rendered more and more circular and regular, increasing at the same time in
diameter.  I have here given a drawing (Fig. 60) of the natural size of an
ocellus not as yet quite perfect.  The lower part of the black ring is much
more curved than is the lower mark in the elliptic ornament (b, Fig. 59).
The upper part of the ring consists of two or three separate portions; and
there is only a trace of the thickening of the portion which forms the
black mark above the white shade.  This white shade itself is not as yet
much concentrated; and beneath it the surface is brighter coloured than in
a perfect ball-and-socket ocellus.  Even in the most perfect ocelli traces
of the junction of three or four elongated black marks, by which the ring
has been formed, may often be detected.  The irregular sub-triangular or
narrow mark (d, Fig. 59), manifestly forms, by its contraction and
equalisation, the thickened portion of the ring above the white shade on a
perfect ball-and-socket ocellus.  The lower part of the ring is invariably
a little thicker than the other parts (Fig. 57), and this follows from the
lower black mark of the elliptic ornament (b, Fig. 59) having originally
been thicker than the upper mark (c).  Every step can be followed in the
process of confluence and modification; and the black ring which surrounds
the ball of the ocellus is unquestionably formed by the union and
modification of the three black marks, b, c, d, of the elliptic ornament.
The irregular zigzag black marks between the successive ocelli (Fig. 57)
are plainly due to the breaking up of the somewhat more regular but similar
marks between the elliptic ornaments.

The successive steps in the shading of the ball-and-socket ocelli can be
followed out with equal clearness.  The brown, orange, and pale-leadened
narrow zones, which border the lower black mark of the elliptic ornament,
can be seen gradually to become more and more softened and shaded into each
other, with the upper lighter part towards the left-hand corner rendered
still lighter, so as to become almost white, and at the same time more
contracted.  But even in the most perfect ball-and-socket ocelli a slight
difference in the tints, though not in the shading, between the upper and
lower parts of the ball can be perceived, as before noticed; and the line
of separation is oblique, in the same direction as the bright coloured
shades of the elliptic ornaments.  Thus almost every minute detail in the
shape and colouring of the ball-and-socket ocelli can be shewn to follow
from gradual changes in the elliptic ornaments; and the development of the
latter can be traced by equally small steps from the union of two almost
simple spots, the lower one (Fig. 58) having some dull fulvous shading on
its upper side.

[Fig. 61.  Portion near summit of one of the secondary wing-feathers,
bearing perfect ball-and-socket ocelli.
a.  Ornamented upper part.
b.  Uppermost, imperfect ball-and-socket ocellus.  (The shading above the
white mark on the summit of the ocellus is here a little too dark.)
c.  Perfect ocellus.]

The extremities of the longer secondary feathers which bear the perfect
ball-and-socket ocelli, are peculiarly ornamented (Fig. 61).  The oblique
longitudinal stripes suddenly cease upwards and become confused; and above
this limit the whole upper end of the feather (a) is covered with white
dots, surrounded by little black rings, standing on a dark ground.  The
oblique stripe belonging to the uppermost ocellus (b) is barely represented
by a very short irregular black mark with the usual, curved, transverse
base.  As this stripe is thus abruptly cut off, we can perhaps understand
from what has gone before, how it is that the upper thickened part of the
ring is here absent; for, as before stated, this thickened part apparently
stands in some relation with a broken prolongation from the next higher
spot.  From the absence of the upper and thickened part of the ring, the
uppermost ocellus, though perfect in all other respects, appears as if its
top had been obliquely sliced off.  It would, I think, perplex any one, who
believes that the plumage of the Argus pheasant was created as we now see
it, to account for the imperfect condition of the uppermost ocellus.  I
should add that on the secondary wing-feather farthest from the body all
the ocelli are smaller and less perfect than on the other feathers, and
have the upper part of the ring deficient, as in the case just mentioned.
The imperfection here seems to be connected with the fact that the spots on
this feather shew less tendency than usual to become confluent into
stripes; they are, on the contrary, often broken up into smaller spots, so
that two or three rows run down to the same ocellus.

There still remains another very curious point, first observed by Mr. T.W.
Wood (51.  The 'Field,' May 28, 1870.), which deserves attention.  In a
photograph, given me by Mr. Ward, of a specimen mounted as in the act of
display, it may be seen that on the feathers which are held
perpendicularly, the white marks on the ocelli, representing light
reflected from a convex surface, are at the upper or further end, that is,
are directed upwards; and the bird whilst displaying himself on the ground
would naturally be illuminated from above.  But here comes the curious
point; the outer feathers are held almost horizontally, and their ocelli
ought likewise to appear as if illuminated from above, and consequently the
white marks ought to be placed on the upper sides of the ocelli; and,
wonderful as is the fact, they are thus placed!  Hence the ocelli on the
several feathers, though occupying very different positions with respect to
the light, all appear as if illuminated from above, just as an artist would
have shaded them.  Nevertheless they are not illuminated from strictly the
same point as they ought to be; for the white marks on the ocelli of the
feathers which are held almost horizontally, are placed rather too much
towards the further end; that is, they are not sufficiently lateral.  We
have, however, no right to expect absolute perfection in a part rendered
ornamental through sexual selection, any more than we have in a part
modified through natural selection for real use; for instance, in that
wondrous organ the human eye.  And we know what Helmholtz, the highest
authority in Europe on the subject, has said about the human eye; that if
an optician had sold him an instrument so carelessly made, he would have
thought himself fully justified in returning it.  (52.  'Popular Lectures
on Scientific Subjects,' Eng. trans. 1873, pp. 219, 227, 269, 390.)

We have now seen that a perfect series can be followed, from simple spots
to the wonderful ball-and-socket ornaments.  Mr. Gould, who kindly gave me
some of these feathers, fully agrees with me in the completeness of the
gradation.  It is obvious that the stages in development exhibited by the
feathers on the same bird do not at all necessarily shew us the steps
passed through by the extinct progenitors of the species; but they probably
give us the clue to the actual steps, and they at least prove to
demonstration that a gradation is possible.  Bearing in mind how carefully
the male Argus pheasant displays his plumes before the female, as well as
the many facts rendering it probable that female birds prefer the more
attractive males, no one who admits the agency of sexual selection in any
case will deny that a simple dark spot with some fulvous shading might be
converted, through the approximation and modification of two adjoining
spots, together with some slight increase of colour, into one of the so-
called elliptic ornaments.  These latter ornaments have been shewn to many
persons, and all have admitted that they are beautiful, some thinking them
even more so than the ball-and-socket ocelli.  As the secondary plumes
became lengthened through sexual selection, and as the elliptic ornaments
increased in diameter, their colours apparently became less bright; and
then the ornamentation of the plumes had to be gained by an improvement in
the pattern and shading; and this process was carried on until the
wonderful ball-and-socket ocelli were finally developed.  Thus we can
understand--and in no other way as it seems to me--the present condition
and origin of the ornaments on the wing-feathers of the Argus pheasant.

From the light afforded by the principle of gradation--from what we know of
the laws of variation--from the changes which have taken place in many of
our domesticated birds--and, lastly, from the character (as we shall
hereafter see more clearly) of the immature plumage of young birds--we can
sometimes indicate, with a certain amount of confidence, the probable steps
by which the males have acquired their brilliant plumage and various
ornaments; yet in many cases we are involved in complete darkness.  Mr.
Gould several years ago pointed out to me a humming-bird, the Urosticte
benjamini, remarkable for the curious differences between the sexes.  The
male, besides a splendid gorget, has greenish-black tail-feathers, with the
four CENTRAL ones tipped with white; in the female, as with most of the
allied species, the three OUTER tail-feathers on each side are tipped with
white, so that the male has the four central, whilst the female has the six
exterior feathers ornamented with white tips.  What makes the case more
curious is that, although the colouring of the tail differs remarkably in
both sexes of many kinds of humming-birds, Mr. Gould does not know a single
species, besides the Urosticte, in which the male has the four central
feathers tipped with white.

The Duke of Argyll, in commenting on this case (53.  'The Reign of Law,'
1867, p. 247.), passes over sexual selection, and asks, "What explanation
does the law of natural selection give of such specific varieties as
these?"  He answers "none whatever"; and I quite agree with him.  But can
this be so confidently said of sexual selection?  Seeing in how many ways
the tail-feathers of humming-birds differ, why should not the four central
feathers have varied in this one species alone, so as to have acquired
white tips?  The variations may have been gradual, or somewhat abrupt as in
the case recently given of the humming-birds near Bogota, in which certain
individuals alone have the "central tail-feathers tipped with beautiful
green."  In the female of the Urosticte I noticed extremely minute or
rudimental white tips to the two outer of the four central black tail-
feathers; so that here we have an indication of change of some kind in the
plumage of this species.  If we grant the possibility of the central tail-
feathers of the male varying in whiteness, there is nothing strange in such
variations having been sexually selected.  The white tips, together with
the small white ear-tufts, certainly add, as the Duke of Argyll admits, to
the beauty of the male; and whiteness is apparently appreciated by other
birds, as may be inferred from such cases as the snow-white male of the
Bell-bird.  The statement made by Sir R. Heron should not be forgotten,
namely, that his peahens, when debarred from access to the pied peacock,
would not unite with any other male, and during that season produced no
offspring.  Nor is it strange that variations in the tail-feathers of the
Urosticte should have been specially selected for the sake of ornament, for
the next succeeding genus in the family takes its name of Metallura from
the splendour of these feathers.  We have, moreover, good evidence that
humming-birds take especial pains in displaying their tail-feathers; Mr.
Belt (54.  'The Naturalist in Nicaragua,' 1874, p. 112.), after describing
the beauty of the Florisuga mellivora, says, "I have seen the female
sitting on a branch, and two males displaying their charms in front of her.
One would shoot up like a rocket, then suddenly expanding the snow-white
tail, like an inverted parachute, slowly descend in front of her, turning
round gradually to shew off back and front...The expanded white tail
covered more space than all the rest of the bird, and was evidently the
grand feature in the performance.  Whilst one male was descending, the
other would shoot up and come slowly down expanded.  The entertainment
would end in a fight between the two performers; but whether the most
beautiful or the most pugnacious was the accepted suitor, I know not."  Mr.
Gould, after describing the peculiar plumage of the Urosticte, adds, "that
ornament and variety is the sole object, I have myself but little doubt."
(55.  'Introduction to the Trochilidae,' 1861, p. 110.)  If this be
admitted, we can perceive that the males which during former times were
decked in the most elegant and novel manner would have gained an advantage,
not in the ordinary struggle for life, but in rivalry with other males, and
would have left a larger number of offspring to inherit their newly-
acquired beauty.


CHAPTER XV.

Birds--continued.

Discussion as to why the males alone of some species, and both sexes of
others, are brightly coloured--On sexually-limited inheritance, as applied
to various structures and to brightly-coloured plumage--Nidification in
relation to colour--Loss of nuptial plumage during the winter.

We have in this chapter to consider why the females of many birds have not
acquired the same ornaments as the male; and why, on the other hand, both
sexes of many other birds are equally, or almost equally, ornamented?  In
the following chapter we shall consider the few cases in which the female
is more conspicuously coloured than the male.

In my 'Origin of Species' (1.  Fourth edition, 1866, p. 241.) I briefly
suggested that the long tail of the peacock would be inconvenient and the
conspicuous black colour of the male capercailzie dangerous, to the female
during the period of incubation:  and consequently that the transmission of
these characters from the male to the female offspring had been checked
through natural selection.  I still think that this may have occurred in
some few instances:  but after mature reflection on all the facts which I
have been able to collect, I am now inclined to believe that when the sexes
differ, the successive variations have generally been from the first
limited in their transmission to the same sex in which they first arose.
Since my remarks appeared, the subject of sexual coloration has been
discussed in some very interesting papers by Mr. Wallace (2.  'Westminster
Review,' July 1867.  'Journal of Travel,' vol. i. 1868, p. 73.), who
believes that in almost all cases the successive variations tended at first
to be transmitted equally to both sexes; but that the female was saved,
through natural selection, from acquiring the conspicuous colours of the
male, owing to the danger which she would thus have incurred during
incubation.

This view necessitates a tedious discussion on a difficult point, namely,
whether the transmission of a character, which is at first inherited by
both sexes can be subsequently limited in its transmission to one sex alone
by means of natural selection.  We must bear in mind, as shewn in the
preliminary chapter on sexual selection, that characters which are limited
in their development to one sex are always latent in the other.  An
imaginary illustration will best aid us in seeing the difficulty of the
case; we may suppose that a fancier wished to make a breed of pigeons, in
which the males alone should be coloured of a pale blue, whilst the females
retained their former slaty tint.  As with pigeons characters of all kinds
are usually transmitted to both sexes equally, the fancier would have to
try to convert this latter form of inheritance into sexually-limited
transmission.  All that he could do would be to persevere in selecting
every male pigeon which was in the least degree of a paler blue; and the
natural result of this process, if steadily carried on for a long time, and
if the pale variations were strongly inherited or often recurred, would be
to make his whole stock of a lighter blue.  But our fancier would be
compelled to match, generation after generation, his pale blue males with
slaty females, for he wishes to keep the latter of this colour.  The result
would generally be the production either of a mongrel piebald lot, or more
probably the speedy and complete loss of the pale-blue tint; for the
primordial slaty colour would be transmitted with prepotent force.
Supposing, however, that some pale-blue males and slaty females were
produced during each successive generation, and were always crossed
together, then the slaty females would have, if I may use the expression,
much blue blood in their veins, for their fathers, grandfathers, etc., will
all have been blue birds.  Under these circumstances it is conceivable
(though I know of no distinct facts rendering it probable) that the slaty
females might acquire so strong a latent tendency to pale-blueness, that
they would not destroy this colour in their male offspring, their female
offspring still inheriting the slaty tint.  If so, the desired end of
making a breed with the two sexes permanently different in colour might be
gained.

The extreme importance, or rather necessity in the above case of the
desired character, namely, pale-blueness, being present though in a latent
state in the female, so that the male offspring should not be deteriorated,
will be best appreciated as follows:  the male of Soemmerring's pheasant
has a tail thirty-seven inches in length, whilst that of the female is only
eight inches; the tail of the male common pheasant is about twenty inches,
and that of the female twelve inches long.  Now if the female Soemmerring
pheasant with her SHORT tail were crossed with the male common pheasant,
there can be no doubt that the male hybrid offspring would have a much
LONGER tail than that of the pure offspring of the common pheasant.  On the
other hand, if the female common pheasant, with a tail much longer than
that of the female Soemmerring pheasant, were crossed with the male of the
latter, the male hybrid offspring would have a much SHORTER tail than that
of the pure offspring of Soemmerring's pheasant.  (3.  Temminck says that
the tail of the female Phasianus Soemmerringii is only six inches long,
'Planches coloriees,' vol. v. 1838, pp. 487 and 488:  the measurements
above given were made for me by Mr. Sclater.  For the common pheasant, see
Macgillivray, 'History of British Birds,' vol. i. pp. 118-121.)

Our fancier, in order to make his new breed with the males of a pale-blue
tint, and the females unchanged, would have to continue selecting the males
during many generations; and each stage of paleness would have to be fixed
in the males, and rendered latent in the females.  The task would be an
extremely difficult one, and has never been tried, but might possibly be
successfully carried out.  The chief obstacle would be the early and
complete loss of the pale-blue tint, from the necessity of reiterated
crosses with the slaty female, the latter not having at first any LATENT
tendency to produce pale-blue offspring.

On the other hand, if one or two males were to vary ever so slightly in
paleness, and the variations were from the first limited in their
transmission to the male sex, the task of making a new breed of the desired
kind would be easy, for such males would simply have to be selected and
matched with ordinary females.  An analogous case has actually occurred,
for there are breeds of the pigeon in Belgium (4.  Dr. Chapuis, 'Le Pigeon
Voyageur Belge,' 1865, p. 87.) in which the males alone are marked with
black striae.  So again Mr. Tegetmeier has recently shewn (5.  The 'Field,'
Sept. 1872.) that dragons not rarely produce silver-coloured birds, which
are almost always hens; and he himself has bred ten such females.  It is on
the other hand a very unusual event when a silver male is produced; so that
nothing would be easier, if desired, than to make a breed of dragons with
blue males and silver females.  This tendency is indeed so strong that when
Mr. Tegetmeier at last got a silver male and matched him with one of the
silver females, he expected to get a breed with both sexes thus coloured;
he was however disappointed, for the young male reverted to the blue colour
of his grandfather, the young female alone being silver.  No doubt with
patience this tendency to reversion in the males, reared from an occasional
silver male matched with a silver hen, might be eliminated, and then both
sexes would be coloured alike; and this very process has been followed with
success by Mr. Esquilant in the case of silver turbits.

With fowls, variations of colour, limited in their transmission to the male
sex, habitually occur.  When this form of inheritance prevails, it might
well happen that some of the successive variations would be transferred to
the female, who would then slightly resemble the male, as actually occurs
in some breeds.  Or again, the greater number, but not all, of the
successive steps might be transferred to both sexes, and the female would
then closely resemble the male.  There can hardly be a doubt that this is
the cause of the male pouter pigeon having a somewhat larger crop, and of
the male carrier pigeon having somewhat larger wattles, than their
respective females; for fanciers have not selected one sex more than the
other, and have had no wish that these characters should be more strongly
displayed in the male than in the female, yet this is the case with both
breeds.

The same process would have to be followed, and the same difficulties
encountered, if it were desired to make a breed with the females alone of
some new colour.

Lastly, our fancier might wish to make a breed with the two sexes differing
from each other, and both from the parent species.  Here the difficulty
would be extreme, unless the successive variations were from the first
sexually limited on both sides, and then there would be no difficulty.  We
see this with the fowl; thus the two sexes of the pencilled Hamburghs
differ greatly from each other, and from the two sexes of the aboriginal
Gallus bankiva; and both are now kept constant to their standard of
excellence by continued selection, which would be impossible unless the
distinctive characters of both were limited in their transmission.

The Spanish fowl offers a more curious case; the male has an immense comb,
but some of the successive variations, by the accumulation of which it was
acquired, appear to have been transferred to the female; for she has a comb
many times larger than that of the females of the parent species.  But the
comb of the female differs in one respect from that of the male, for it is
apt to lop over; and within a recent period it has been ordered by the
fancy that this should always be the case, and success has quickly followed
the order.  Now the lopping of the comb must be sexually limited in its
transmission, otherwise it would prevent the comb of the male from being
perfectly upright, which would be abhorrent to every fancier.  On the other
hand, the uprightness of the comb in the male must likewise be a sexually-
limited character, otherwise it would prevent the comb of the female from
lopping over.

From the foregoing illustrations, we see that even with almost unlimited
time at command, it would be an extremely difficult and complex, perhaps an
impossible process, to change one form of transmission into the other
through selection.  Therefore, without distinct evidence in each case, I am
unwilling to admit that this has been effected in natural species.  On the
other hand, by means of successive variations, which were from the first

sexually limited in their transmission, there would not be the least
difficulty in rendering a male bird widely different in colour or in any
other character from the female; the latter being left unaltered, or
slightly altered, or specially modified for the sake of protection.

As bright colours are of service to the males in their rivalry with other
males, such colours would be selected whether or not they were transmitted
exclusively to the same sex.  Consequently the females might be expected
often to partake of the brightness of the males to a greater or less
degree; and this occurs with a host of species.  If all the successive
variations were transmitted equally to both sexes, the females would be
indistinguishable from the males; and this likewise occurs with many birds.
If, however, dull colours were of high importance for the safety of the
female during incubation, as with many ground birds, the females which
varied in brightness, or which received through inheritance from the males
any marked accession of brightness, would sooner or later be destroyed.
But the tendency in the males to continue for an indefinite period
transmitting to their female offspring their own brightness, would have to
be eliminated by a change in the form of inheritance; and this, as shewn by
our previous illustration, would be extremely difficult.  The more probable
result of the long-continued destruction of the more brightly-coloured
females, supposing the equal form of transmission to prevail, would be the
lessening or annihilation of the bright colours of the males, owing to
their continual crossing with the duller females.  It would be tedious to
follow out all the other possible results; but I may remind the reader that
if sexually-limited variations in brightness occurred in the females, even
if they were not in the least injurious to them and consequently were not
eliminated, yet they would not be favoured or selected, for the male
usually accepts any female, and does not select the more attractive
individuals; consequently these variations would be liable to be lost, and
would have little influence on the character of the race; and this will aid
in accounting for the females being commonly duller-coloured than the
males.

In the eighth chapter instances were given, to which many might here be
added, of variations occurring at various ages, and inherited at the
corresponding age.  It was also shewn that variations which occur late in
life are commonly transmitted to the same sex in which they first appear;
whilst variations occurring early in life are apt to be transmitted to both
sexes; not that all the cases of sexually-limited transmission can thus be
accounted for.  It was further shewn that if a male bird varied by becoming
brighter whilst young, such variations would be of no service until the age
for reproduction had arrived, and there was competition between rival
males.  But in the case of birds living on the ground and commonly in need
of the protection of dull colours, bright tints would be far more dangerous
to the young and inexperienced than to the adult males.  Consequently the
males which varied in brightness whilst young would suffer much destruction
and be eliminated through natural selection; on the other hand, the males
which varied in this manner when nearly mature, notwithstanding that they
were exposed to some additional danger, might survive, and from being
favoured through sexual selection, would procreate their kind.  As a
relation often exists between the period of variation and the form of
transmission, if the bright-coloured young males were destroyed and the
mature ones were successful in their courtship, the males alone would
acquire brilliant colours and would transmit them exclusively to their male
offspring.  But I by no means wish to maintain that the influence of age on
the form of transmission, is the sole cause of the great difference in
brilliancy between the sexes of many birds.

When the sexes of birds differ in colour, it is interesting to determine
whether the males alone have been modified by sexual selection, the females
having been left unchanged, or only partially and indirectly thus changed;
or whether the females have been specially modified through natural
selection for the sake of protection.  I will therefore discuss this
question at some length, even more fully than its intrinsic importance
deserves; for various curious collateral points may thus be conveniently
considered.

Before we enter on the subject of colour, more especially in reference to
Mr. Wallace's conclusions, it may be useful to discuss some other sexual
differences under a similar point of view.  A breed of fowls formerly
existed in Germany (6.  Bechstein, 'Naturgeschichte Deutschlands,' 1793, B.
iii. 339.) in which the hens were furnished with spurs; they were good
layers, but they so greatly disturbed their nests with their spurs that
they could not be allowed to sit on their own eggs.  Hence at one time it
appeared to me probable that with the females of the wild Gallinaceae the
development of spurs had been checked through natural selection, from the
injury thus caused to their nests.  This seemed all the more probable, as
wing-spurs, which would not be injurious during incubation, are often as
well-developed in the female as in the male; though in not a few cases they
are rather larger in the male.  When the male is furnished with leg-spurs
the female almost always exhibits rudiments of them,--the rudiment
sometimes consisting of a mere scale, as in Gallus.  Hence it might be
argued that the females had aboriginally been furnished with well-developed
spurs, but that these had subsequently been lost through disuse or natural
selection.  But if this view be admitted, it would have to be extended to
innumerable other cases; and it implies that the female progenitors of the
existing spur-bearing species were once encumbered with an injurious
appendage.

In some few genera and species, as in Galloperdix, Acomus, and the Javan
peacock (Pavo muticus), the females, as well as the males, possess well-
developed leg-spurs.  Are we to infer from this fact that they construct a
different sort of nest from that made by their nearest allies, and not
liable to be injured by their spurs; so that the spurs have not been
removed?  Or are we to suppose that the females of these several species
especially require spurs for their defence?  It is a more probable
conclusion that both the presence and absence of spurs in the females
result from different laws of inheritance having prevailed, independently
of natural selection.  With the many females in which spurs appear as
rudiments, we may conclude that some few of the successive variations,
through which they were developed in the males, occurred very early in
life, and were consequently transferred to the females.  In the other and
much rarer cases, in which the females possess fully developed spurs, we
may conclude that all the successive variations were transferred to them;
and that they gradually acquired and inherited the habit of not disturbing
their nests.

The vocal organs and the feathers variously modified for producing sound,
as well as the proper instincts for using them, often differ in the two
sexes, but are sometimes the same in both.  Can such differences be
accounted for by the males having acquired these organs and instincts,
whilst the females have been saved from inheriting them, on account of the
danger to which they would have been exposed by attracting the attention of
birds or beasts of prey?  This does not seem to me probable, when we think
of the multitude of birds which with impunity gladden the country with
their voices during the spring.  (7.  Daines Barrington, however, thought
it probable ('Philosophical Transactions,' 1773, p. 164) that few female
birds sing, because the talent would have been dangerous to them during
incubation.  He adds, that a similar view may possibly account for the
inferiority of the female to the male in plumage.)  It is a safer
conclusion that, as vocal and instrumental organs are of special service
only to the males during their courtship, these organs were developed
through sexual selection and their constant use in that sex alone--the
successive variations and the effects of use having been from the first
more or less limited in transmission to the male offspring.

Many analogous cases could be adduced; those for instance of the plumes on
the head being generally longer in the male than in the female, sometimes
of equal length in both sexes, and occasionally absent in the female,--
these several cases occurring in the same group of birds.  It would be
difficult to account for such a difference between the sexes by the female
having been benefited by possessing a slightly shorter crest than the male,
and its consequent diminution or complete suppression through natural
selection.  But I will take a more favourable case, namely the length of
the tail.  The long train of the peacock would have been not only
inconvenient but dangerous to the peahen during the period of incubation
and whilst accompanying her young.  Hence there is not the least a priori
improbability in the development of her tail having been checked through
natural selection.  But the females of various pheasants, which apparently
are exposed on their open nests to as much danger as the peahen, have tails
of considerable length.  The females as well as the males of the Menura
superba have long tails, and they build a domed nest, which is a great
anomaly in so large a bird.  Naturalists have wondered how the female
Menura could manage her tail during incubation; but it is now known (8.
Mr. Ramsay, in 'Proc. Zoolog. Soc.' 1868, p. 50.) that she "enters the nest
head first, and then turns round with her tail sometimes over her back, but
more often bent round by her side.  Thus in time the tail becomes quite
askew, and is a tolerable guide to the length of time the bird has been
sitting."  Both sexes of an Australian kingfisher (Tanysiptera sylvia) have
the middle tail-feathers greatly lengthened, and the female makes her nest
in a hole; and as I am informed by Mr. R.B. Sharpe these feathers become
much crumpled during incubation.

In these two latter cases the great length of the tail-feathers must be in
some degree inconvenient to the female; and as in both species the tail-
feathers of the female are somewhat shorter than those of the male, it
might be argued that their full development had been prevented through
natural selection.  But if the development of the tail of the peahen had
been checked only when it became inconveniently or dangerously great, she
would have retained a much longer tail than she actually possesses; for her
tail is not nearly so long, relatively to the size of her body, as that of
many female pheasants, nor longer than that of the female turkey.  It must
also be borne in mind that, in accordance with this view, as soon as the
tail of the peahen became dangerously long, and its development was
consequently checked, she would have continually reacted on her male
progeny, and thus have prevented the peacock from acquiring his present
magnificent train.  We may therefore infer that the length of the tail in
the peacock and its shortness in the peahen are the result of the requisite
variations in the male having been from the first transmitted to the male
offspring alone.

We are led to a nearly similar conclusion with respect to the length of the
tail in the various species of pheasants.  In the Eared pheasant
(Crossoptilon auritum) the tail is of equal length in both sexes, namely
sixteen or seventeen inches; in the common pheasant it is about twenty
inches long in the male and twelve in the female; in Soemmerring's
pheasant, thirty-seven inches in the male and only eight in the female; and
lastly in Reeve's pheasant it is sometimes actually seventy-two inches long
in the male and sixteen in the female.  Thus in the several species, the
tail of the female differs much in length, irrespectively of that of the
male; and this can be accounted for, as it seems to me, with much more
probability, by the laws of inheritance,--that is by the successive
variations having been from the first more or less closely limited in their
transmission to the male sex than by the agency of natural selection,
resulting from the length of tail being more or less injurious to the
females of these several allied species.

We may now consider Mr. Wallace's arguments in regard to the sexual
coloration of birds.  He believes that the bright tints originally acquired
through sexual selection by the males would in all, or almost all cases,
have been transmitted to the females, unless the transference had been
checked through natural selection.  I may here remind the reader that
various facts opposed to this view have already been given under reptiles,
amphibians, fishes and lepidoptera.  Mr. Wallace rests his belief chiefly,
but not exclusively, as we shall see in the next chapter, on the following
statement (9.  'Journal of Travel,' edited by A. Murray, vol. i. 1868, p.
78.), that when both sexes are coloured in a very conspicuous manner, the
nest is of such a nature as to conceal the sitting bird; but when there is
a marked contrast of colour between the sexes, the male being gay and the
female dull-coloured, the nest is open and exposes the sitting bird to
view.  This coincidence, as far as it goes, certainly seems to favour the
belief that the females which sit on open nests have been specially
modified for the sake of protection; but we shall presently see that there
is another and more probable explanation, namely, that conspicuous females
have acquired the instinct of building domed nests oftener than dull-
coloured birds.  Mr. Wallace admits that there are, as might have been
expected, some exceptions to his two rules, but it is a question whether
the exceptions are not so numerous as seriously to invalidate them.

There is in the first place much truth in the Duke of Argyll's remark (10.
'Journal of Travel,' edited by A. Murray, vol. i. 1868, p. 281.) that a
large domed nest is more conspicuous to an enemy, especially to all tree-
haunting carnivorous animals, than a smaller open nest.  Nor must we forget
that with many birds which build open nests, the male sits on the eggs and
aids the female in feeding the young:  this is the case, for instance, with
Pyranga aestiva (11.  Audubon, 'Ornithological Biography,' vol. i. p.
233.), one of the most splendid birds in the United States, the male being
vermilion, and the female light brownish-green.  Now if brilliant colours
had been extremely dangerous to birds whilst sitting on their open nests,
the males in these cases would have suffered greatly.  It might, however,
be of such paramount importance to the male to be brilliantly coloured, in
order to beat his rivals, that this may have more than compensated some
additional danger.

Mr. Wallace admits that with the King-crows (Dicrurus), Orioles, and
Pittidae, the females are conspicuously coloured, yet build open nests; but
he urges that the birds of the first group are highly pugnacious and could
defend themselves; that those of the second group take extreme care in
concealing their open nests, but this does not invariably hold good (12.
Jerdon, 'Birds of India,' vol. ii. p. 108.  Gould's 'Handbook of the Birds
of Australia,' vol. i. p. 463.); and that with the birds of the third group
the females are brightly coloured chiefly on the under surface.  Besides
these cases, pigeons which are sometimes brightly, and almost always
conspicuously coloured, and which are notoriously liable to the attacks of
birds of prey, offer a serious exception to the rule, for they almost
always build open and exposed nests.  In another large family, that of the
humming-birds, all the species build open nests, yet with some of the most
gorgeous species the sexes are alike; and in the majority, the females,
though less brilliant than the males, are brightly coloured.  Nor can it be
maintained that all female humming-birds, which are brightly coloured,
escape detection by their tints being green, for some display on their
upper surfaces red, blue, and other colours.  (13.  For instance, the
female Eupetomena macroura has the head and tail dark blue with reddish
loins; the female Lampornis porphyrurus is blackish-green on the upper
surface, with the lores and sides of the throat crimson; the female
Eulampis jugularis has the top of the head and back green, but the loins
and the tail are crimson.  Many other instances of highly conspicuous
females could be given.  See Mr. Gould's magnificent work on this family.)

In regard to birds which build in holes or construct domed nests, other
advantages, as Mr. Wallace remarks, besides concealment are gained, such as
shelter from the rain, greater warmth, and in hot countries protection from
the sun (14.  Mr. Salvin noticed in Guatemala ('Ibis,' 1864, p. 375) that
humming-birds were much more unwilling to leave their nests during very hot
weather, when the sun was shining brightly, as if their eggs would be thus
injured, than during cool, cloudy, or rainy weather.); so that it is no
valid objection to his view that many birds having both sexes obscurely
coloured build concealed nests.  (15.  I may specify, as instances of dull-
coloured birds building concealed nests, the species belonging to eight
Australian genera described in Gould's 'Handbook of the Birds of
Australia,' vol. i. pp. 340, 362, 365, 383, 387, 389, 391, 414.)  The
female Horn-bill (Buceros), for instance, of India and Africa is protected
during incubation with extraordinary care, for she plasters up with her own
excrement the orifice of the hole in which she sits on her eggs, leaving
only a small orifice through which the male feeds her; she is thus kept a
close prisoner during the whole period of incubation (16.  Mr. C. Horne,
'Proc. Zoolog. Soc.' 1869. p. 243.); yet female horn-bills are not more
conspicuously coloured than many other birds of equal size which build open
nests.  It is a more serious objection to Mr. Wallace's view, as is
admitted by him, that in some few groups the males are brilliantly coloured
and the females obscure, and yet the latter hatch their eggs in domed
nests.  This is the case with the Grallinae of Australia, the Superb
Warblers (Maluridae) of the same country, the Sun-birds (Nectariniae), and
with several of the Australian Honey-suckers or Meliphagidae.  (17.  On the
nidification and colours of these latter species, see Gould's 'Handbook to
the Birds of Australia,' vol. i. pp. 504, 527.)

If we look to the birds of England we shall see that there is no close and
general relation between the colours of the female and the nature of the
nest which is constructed.  About forty of our British birds (excluding
those of large size which could defend themselves) build in holes in banks,
rocks, or trees, or construct domed nests.  If we take the colours of the
female goldfinch, bullfinch, or blackbird, as a standard of the degree of
conspicuousness, which is not highly dangerous to the sitting female, then
out of the above forty birds the females of only twelve can be considered
as conspicuous to a dangerous degree, the remaining twenty-eight being
inconspicuous.  (18.  I have consulted, on this subject, Macgillivray's
'British Birds,' and though doubts may be entertained in some cases in
regard to the degree of concealment of the nest, and to the degree of
conspicuousness of the female, yet the following birds, which all lay their
eggs in holes or in domed nests, can hardly be considered, by the above
standard, as conspicuous:  Passer, 2 species; Sturnus, of which the female
is considerably less brilliant than the male; Cinclus; Motallica boarula
(?); Erithacus (?); Fruticola, 2 sp.; Saxicola; Ruticilla, 2 sp.; Sylvia, 3
sp.; Parus, 3 sp.; Mecistura; Anorthura; Certhia; Sitta; Yunx; Muscicapa, 2
sp.; Hirundo, 3 sp.; and Cypselus.  The females of the following 12 birds
may be considered as conspicuous according to the same standard, viz.,
Pastor, Motacilla alba, Parus major and P. caeruleus, Upupa, Picus, 4 sp.,
Coracias, Alcedo, and Merops.)  Nor is there any close relation within the
same genus between a well-pronounced difference in colour between the
sexes, and the nature of the nest constructed.  Thus the male house sparrow
(Passer domesticus) differs much from the female, the male tree-sparrow (P.
montanus) hardly at all, and yet both build well-concealed nests.  The two
sexes of the common fly-catcher (Muscicapa grisola) can hardly be
distinguished, whilst the sexes of the pied fly-catcher (M. luctuosa)
differ considerably, and both species build in holes or conceal their
nests.  The female blackbird (Turdus merula) differs much, the female ring-
ouzel (T. torquatus) differs less, and the female common thrush (T.
musicus) hardly at all from their respective males; yet all build open
nests.  On the other hand, the not very distantly-allied water-ouzel
(Cinclus aquaticus) builds a domed nest, and the sexes differ about as much
as in the ring-ouzel.  The black and red grouse (Tetrao tetrix and T.
scoticus) build open nests in equally well-concealed spots, but in the one
species the sexes differ greatly, and in the other very little.

Notwithstanding the foregoing objections, I cannot doubt, after reading Mr.
Wallace's excellent essay, that looking to the birds of the world, a large
majority of the species in which the females are conspicuously coloured
(and in this case the males with rare exceptions are equally conspicuous),
build concealed nests for the sake of protection.  Mr. Wallace enumerates
(19.  'Journal of Travel,' edited by A. Murray, vol. i. p. 78.) a long
series of groups in which this rule holds good; but it will suffice here to
give, as instances, the more familiar groups of kingfishers, toucans,
trogons, puff-birds (Capitonidae), plantain-eaters (Musophagae,
woodpeckers, and parrots.  Mr. Wallace believes that in these groups, as
the males gradually acquired through sexual selection their brilliant
colours, these were transferred to the females and were not eliminated by
natural selection, owing to the protection which they already enjoyed from
their manner of nidification.  According to this view, their present manner
of nesting was acquired before their present colours.  But it seems to me
much more probable that in most cases, as the females were gradually
rendered more and more brilliant from partaking of the colours of the male,
they were gradually led to change their instincts (supposing that they
originally built open nests), and to seek protection by building domed or
concealed nests.  No one who studies, for instance, Audubon's account of
the differences in the nests of the same species in the Northern and
Southern United States (20.  See many statements in the 'Ornithological
Biography.'  See also some curious observations on the nests of Italian
birds by Eugenio Bettoni, in the 'Atti della Societa Italiana,' vol. xi.
1869, p. 487.), will feel any great difficulty in admitting that birds,
either by a change (in the strict sense of the word) of their habits, or
through the natural selection of so-called spontaneous variations of
instinct, might readily be led to modify their manner of nesting.

This way of viewing the relation, as far as it holds good, between the
bright colours of female birds and their manner of nesting, receives some
support from certain cases occurring in the Sahara Desert.  Here, as in
most other deserts, various birds, and many other animals, have had their
colours adapted in a wonderful manner to the tints of the surrounding
surface.  Nevertheless there are, as I am informed by the Rev. Mr.
Tristram, some curious exceptions to the rule; thus the male of the
Monticola cyanea is conspicuous from his bright blue colour, and the female
almost equally conspicuous from her mottled brown and white plumage; both
sexes of two species of Dromolaea are of a lustrous black; so that these
three species are far from receiving protection from their colours, yet
they are able to survive, for they have acquired the habit of taking refuge
from danger in holes or crevices in the rocks.

With respect to the above groups in which the females are conspicuously
coloured and build concealed nests, it is not necessary to suppose that
each separate species had its nidifying instinct specially modified; but
only that the early progenitors of each group were gradually led to build
domed or concealed nests, and afterwards transmitted this instinct,
together with their bright colours, to their modified descendants.  As far
as it can be trusted, the conclusion is interesting, that sexual selection
together with equal or nearly equal inheritance by both sexes, have
indirectly determined the manner of nidification of whole groups of birds.

According to Mr. Wallace, even in the groups in which the females, from
being protected in domed nests during incubation, have not had their bright
colours eliminated through natural selection, the males often differ in a
slight, and occasionally in a considerable degree from the females.  This
is a significant fact, for such differences in colour must be accounted for
by some of the variations in the males having been from the first limited
in transmission to the same sex; as it can hardly be maintained that these
differences, especially when very slight, serve as a protection to the
female.  Thus all the species in the splendid group of the Trogons build in
holes; and Mr. Gould gives figures (21.  See his Monograph of the
Trogonidae, 1st edition.) of both sexes of twenty-five species, in all of
which, with one partial exception, the sexes differ sometimes slightly,
sometimes conspicuously, in colour,--the males being always finer than the
females, though the latter are likewise beautiful.  All the species of
kingfishers build in holes, and with most of the species the sexes are
equally brilliant, and thus far Mr. Wallace's rule holds good; but in some
of the Australian species the colours of the females are rather less vivid
than those of the male; and in one splendidly-coloured species, the sexes
differ so much that they were at first thought to be specifically distinct.
(22.  Namely, Cyanalcyon, Gould's 'Handbook to the Birds of Australia,'
vol. i. p. 133; see, also, pp. 130, 136.)  Mr. R.B. Sharpe, who has
especially studied this group, has shewn me some American species (Ceryle)
in which the breast of the male is belted with black.  Again, in
Carcineutes, the difference between the sexes is conspicuous:  in the male
the upper surface is dull-blue banded with black, the lower surface being
partly fawn-coloured, and there is much red about the head; in the female
the upper surface is reddish-brown banded with black, and the lower surface
white with black markings.  It is an interesting fact, as shewing how the
same peculiar style of sexual colouring often characterises allied forms,
that in three species of Dacelo the male differs from the female only in
the tail being dull-blue banded with black, whilst that of the female is
brown with blackish bars; so that here the tail differs in colour in the
two sexes in exactly the same manner as the whole upper surface in the two
sexes of Carcineutes.

With parrots, which likewise build in holes, we find analogous cases:  in
most of the species, both sexes are brilliantly coloured and
indistinguishable, but in not a few species the males are coloured rather
more vividly than the females, or even very differently from them.  Thus,
besides other strongly-marked differences, the whole under surface of the
male King Lory (Aprosmictus scapulatus) is scarlet, whilst the throat and
chest of the female is green tinged with red:  in the Euphema splendida
there is a similar difference, the face and wing coverts moreover of the
female being of a paler blue than in the male.  (23.  Every gradation of
difference between the sexes may be followed in the parrots of Australia.
See Gould's 'Handbook,' etc., vol. ii. pp. 14-102.)  In the family of the
tits (Parinae), which build concealed nests, the female of our common blue
tomtit (Parus caeruleus), is "much less brightly coloured" than the male:
and in the magnificent Sultan yellow tit of India the difference is
greater.  (24.  Macgillivray's 'British Birds,' vol. ii. p. 433.  Jerdon,
'Birds of India,' vol. ii. p. 282.)

Again, in the great group of the woodpeckers (25.  All the following facts
are taken from M. Malherbe's magnificent 'Monographie des Picidees,'
1861.), the sexes are generally nearly alike, but in the Megapicus validus
all those parts of the head, neck, and breast, which are crimson in the
male are pale brown in the female.  As in several woodpeckers the head of
the male is bright crimson, whilst that of the female is plain, it occurred
to me that this colour might possibly make the female dangerously
conspicuous, whenever she put her head out of the hole containing her nest,
and consequently that this colour, in accordance with Mr. Wallace's belief,
had been eliminated.  This view is strengthened by what Malherbe states
with respect to Indopicus carlotta; namely, that the young females, like
the young males, have some crimson about their heads, but that this colour
disappears in the adult female, whilst it is intensified in the adult male.
Nevertheless the following considerations render this view extremely
doubtful:  the male takes a fair share in incubation (26.  Audubon's
'Ornithological Biography,' vol. ii. p. 75; see also the 'Ibis,' vol. i. p.
268.), and would be thus almost equally exposed to danger; both sexes of
many species have their heads of an equally bright crimson; in other
species the difference between the sexes in the amount of scarlet is so
slight that it can hardly make any appreciable difference in the danger
incurred; and lastly, the colouring of the head in the two sexes often
differs slightly in other ways.

The cases, as yet given, of slight and graduated differences in colour
between the males and females in the groups, in which as a general rule the
sexes resemble each other, all relate to species which build domed or
concealed nests.  But similar gradations may likewise be observed in groups
in which the sexes as a general rule resemble each other, but which build
open nests.

As I have before instanced the Australian parrots, so I may here instance,
without giving any details, the Australian pigeons.  (27.  Gould's
'Handbook to the Birds of Australia,' vol. ii. pp. 109-149.)  It deserves
especial notice that in all these cases the slight differences in plumage
between the sexes are of the same general nature as the occasionally
greater differences.  A good illustration of this fact has already been
afforded by those kingfishers in which either the tail alone or the whole
upper surface of the plumage differs in the same manner in the two sexes.
Similar cases may be observed with parrots and pigeons.  The differences in
colour between the sexes of the same species are, also, of the same general
nature as the differences in colour between the distinct species of the
same group.  For when in a group in which the sexes are usually alike, the
male differs considerably from the female, he is not coloured in a quite
new style.  Hence we may infer that within the same group the special
colours of both sexes when they are alike, and the colours of the male,
when he differs slightly or even considerably from the female, have been in
most cases determined by the same general cause; this being sexual
selection.

It is not probable, as has already been remarked, that differences in
colour between the sexes, when very slight, can be of service to the female
as a protection.  Assuming, however, that they are of service, they might
be thought to be cases of transition; but we have no reason to believe that
many species at any one time are undergoing change.  Therefore we can
hardly admit that the numerous females which differ very slightly in colour
from their males are now all commencing to become obscure for the sake of
protection.  Even if we consider somewhat more marked sexual differences,
is it probable, for instance, that the head of the female chaffinch,--the
crimson on the breast of the female bullfinch,--the green of the female
greenfinch,--the crest of the female golden-crested wren, have all been
rendered less bright by the slow process of selection for the sake of
protection?  I cannot think so; and still less with the slight differences
between the sexes of those birds which build concealed nests.  On the other
hand, the differences in colour between the sexes, whether great or small,
may to a large extent be explained on the principle of the successive
variations, acquired by the males through sexual selection, having been
from the first more or less limited in their transmission to the females.
That the degree of limitation should differ in different species of the
same group will not surprise any one who has studied the laws of
inheritance, for they are so complex that they appear to us in our
ignorance to be capricious in their action.  (28.  See remarks to this
effect in 'Variation of Animals and Plants under Domestication,' vol. ii.
chap. xii.)

As far as I can discover there are few large groups of birds in which all
the species have both sexes alike and brilliantly coloured, but I hear from
Mr. Sclater, that this appears to be the case with the Musophagae or
plantain-eaters.  Nor do I believe that any large group exists in which the
sexes of all the species are widely dissimilar in colour:  Mr. Wallace
informs me that the chatterers of S. America (Cotingidae) offer one of the
best instances; but with some of the species, in which the male has a
splendid red breast, the female exhibits some red on her breast; and the
females of other species shew traces of the green and other colours of the
males.  Nevertheless we have a near approach to close sexual similarity or
dissimilarity throughout several groups:  and this, from what has just been
said of the fluctuating nature of inheritance, is a somewhat surprising
circumstance.  But that the same laws should largely prevail with allied
animals is not surprising.  The domestic fowl has produced a great number
of breeds and sub-breeds, and in these the sexes generally differ in
plumage; so that it has been noticed as an unusual circumstance when in
certain sub-breeds they resemble each other.  On the other hand, the
domestic pigeon has likewise produced a vast number of distinct breeds and
sub-breeds, and in these, with rare exceptions, the two sexes are
identically alike.

Therefore if other species of Gallus and Columba were domesticated and
varied, it would not be rash to predict that similar rules of sexual
similarity and dissimilarity, depending on the form of transmission, would
hold good in both cases.  In like manner the same form of transmission has
generally prevailed under nature throughout the same groups, although
marked exceptions to this rule occur.  Thus within the same family or even
genus, the sexes may be identically alike, or very different in colour.
Instances have already been given in the same genus, as with sparrows, fly-
catchers, thrushes and grouse.  In the family of pheasants the sexes of
almost all the species are wonderfully dissimilar, but are quite alike in
the eared pheasant or Crossoptilon auritum.  In two species of Chloephaga,
a genus of geese, the male cannot be distinguished from the females, except
by size; whilst in two others, the sexes are so unlike that they might
easily be mistaken for distinct species.  (29.  The 'Ibis,' vol. vi. 1864,
p. 122.)

The laws of inheritance can alone account for the following cases, in which
the female acquires, late in life, certain characters proper to the male,
and ultimately comes to resemble him more or less completely.  Here
protection can hardly have come into play.  Mr. Blyth informs me that the
females of Oriolus melanocephalus and of some allied species, when
sufficiently mature to breed, differ considerably in plumage from the adult
males; but after the second or third moults they differ only in their beaks
having a slight greenish tinge.  In the dwarf bitterns (Ardetta), according
to the same authority, "the male acquires his final livery at the first
moult, the female not before the third or fourth moult; in the meanwhile
she presents an intermediate garb, which is ultimately exchanged for the
same livery as that of the male."  So again the female Falco peregrinus
acquires her blue plumage more slowly than the male.  Mr. Swinhoe states
that with one of the Drongo shrikes (Dicrurus macrocercus) the male, whilst
almost a nestling, moults his soft brown plumage and becomes of a uniform
glossy greenish-black; but the female retains for a long time the white
striae and spots on the axillary feathers; and does not completely assume
the uniform black colour of the male for three years.  The same excellent
observer remarks that in the spring of the second year the female spoon-
bill (Platalea) of China resembles the male of the first year, and that
apparently it is not until the third spring that she acquires the same
adult plumage as that possessed by the male at a much earlier age.  The
female Bombycilla carolinensis differs very little from the male, but the
appendages, which like beads of red sealing-wax ornament the wing-feathers
(30.  When the male courts the female, these ornaments are vibrated, and
"are shewn off to great advantage," on the outstretched wings:  A. Leith
Adams, 'Field and Forest Rambles,' 1873, p. 153.), are not developed in her
so early in life as in the male.  In the male of an Indian parrakeet
(Palaeornis javanicus) the upper mandible is coral-red from his earliest
youth, but in the female, as Mr. Blyth has observed with caged and wild
birds, it is at first black and does not become red until the bird is at
least a year old, at which age the sexes resemble each other in all
respects.  Both sexes of the wild turkey are ultimately furnished with a
tuft of bristles on the breast, but in two-year-old birds the tuft is about
four inches long in the male and hardly apparent in the female; when,
however, the latter has reached her fourth year, it is from four to five
inches in length.  (31.  On Ardetta, Translation of Cuvier's 'Regne
Animal,' by Mr. Blyth, footnote, p. 159.  On the Peregrine Falcon, Mr.
Blyth, in Charlesworth's 'Mag. of Nat. Hist.' vol. i. 1837, p. 304.  On
Dicrurus, 'Ibis,' 1863, p. 44.  On the Platalea, 'Ibis,' vol. vi. 1864, p.
366.  On the Bombycilla, Audubon's 'Ornitholog.  Biography,' vol. i. p.
229.  On the Palaeornis, see, also, Jerdon, 'Birds of India,' vol. i. p.
263.  On the wild turkey, Audubon, ibid. vol. i. p. 15; but I hear from
Judge Caton that in Illinois the female very rarely acquires a tuft.
Analogous cases with the females of Petrocossyphus are given by Mr. R.
Sharpe, 'Proceedings of the Zoological Society,' 1872, p. 496.)


These cases must not be confounded with those where diseased or old females
abnormally assume masculine characters, nor with those where fertile
females, whilst young, acquire the characters of the male, through
variation or some unknown cause.  (32.  Of these latter cases Mr. Blyth has
recorded (Translation of Cuvier's 'Regne Animal,' p. 158) various instances
with Lanius, Ruticilla, Linaria, and Anas.  Audubon has also recorded a
similar case ('Ornitholog. Biography,' vol. v. p. 519) with Pyranga
aestiva.)  But all these cases have so much in common that they depend,
according to the hypothesis of pangenesis, on gemmules derived from each
part of the male being present, though latent, in the female; their
development following on some slight change in the elective affinities of
her constituent tissues.

A few words must be added on changes of plumage in relation to the season
of the year.  From reasons formerly assigned there can be little doubt that
the elegant plumes, long pendant feathers, crests, etc., of egrets, herons,
and many other birds, which are developed and retained only during the
summer, serve for ornamental and nuptial purposes, though common to both
sexes.  The female is thus rendered more conspicuous during the period of
incubation than during the winter; but such birds as herons and egrets
would be able to defend themselves.  As, however, plumes would probably be
inconvenient and certainly of no use during the winter, it is possible that
the habit of moulting twice in the year may have been gradually acquired
through natural selection for the sake of casting off inconvenient
ornaments during the winter.  But this view cannot be extended to the many
waders, whose summer and winter plumages differ very little in colour.
With defenceless species, in which both sexes, or the males alone, become
extremely conspicuous during the breeding-season,--or when the males
acquire at this season such long wing or tail-feathers as to impede their
flight, as with Cosmetornis and Vidua,--it certainly at first appears
highly probable that the second moult has been gained for the special
purpose of throwing off these ornaments.  We must, however, remember that
many birds, such as some of the Birds of Paradise, the Argus pheasant and
peacock, do not cast their plumes during the winter; and it can hardly be
maintained that the constitution of these birds, at least of the
Gallinaceae, renders a double moult impossible, for the ptarmigan moults
thrice in the year.  (33.  See Gould's 'Birds of Great Britain.')  Hence it
must be considered as doubtful whether the many species which moult their
ornamental plumes or lose their bright colours during the winter, have
acquired this habit on account of the inconvenience or danger which they
would otherwise have suffered.

I conclude, therefore, that the habit of moulting twice in the year was in
most or all cases first acquired for some distinct purpose, perhaps for
gaining a warmer winter covering; and that variations in the plumage
occurring during the summer were accumulated through sexual selection, and
transmitted to the offspring at the same season of the year; that such
variations were inherited either by both sexes or by the males alone,
according to the form of inheritance which prevailed.  This appears more
probable than that the species in all cases originally tended to retain
their ornamental plumage during the winter, but were saved from this
through natural selection, resulting from the inconvenience or danger thus
caused.

I have endeavoured in this chapter to shew that the arguments are not
trustworthy in favour of the view that weapons, bright colours, and various
ornaments, are now confined to the males owing to the conversion, by
natural selection, of the equal transmission of characters to both sexes,
into transmission to the male sex alone.  It is also doubtful whether the
colours of many female birds are due to the preservation, for the sake of
protection, of variations which were from the first limited in their
transmission to the female sex.  But it will be convenient to defer any
further discussion on this subject until I treat, in the following chapter,
of the differences in plumage between the young and old.


CHAPTER XVI.

BIRDS--concluded.

The immature plumage in relation to the character of the plumage in both
sexes when adult--Six classes of cases--Sexual differences between the
males of closely-allied or representative species--The female assuming the
characters of the male--Plumage of the young in relation to the summer and
winter plumage of the adults--On the increase of beauty in the birds of the
world--Protective colouring--Conspicuously coloured birds--Novelty
appreciated--Summary of the four chapters on Birds.

We must now consider the transmission of characters, as limited by age, in
reference to sexual selection.  The truth and importance of the principle
of inheritance at corresponding ages need not here be discussed, as enough
has already been said on the subject.  Before giving the several rather
complex rules or classes of cases, under which the differences in plumage
between the young and the old, as far as known to me, may be included, it
will be well to make a few preliminary remarks.

With animals of all kinds when the adults differ in colour from the young,
and the colours of the latter are not, as far as we can see, of any special
service, they may generally be attributed, like various embryological
structures, to the retention of a former character.  But this view can be
maintained with confidence, only when the young of several species resemble
each other closely, and likewise resemble other adult species belonging to
the same group; for the latter are the living proofs that such a state of
things was formerly possible.  Young lions and pumas are marked with feeble
stripes or rows of spots, and as many allied species both young and old are
similarly marked, no believer in evolution will doubt that the progenitor
of the lion and puma was a striped animal, and that the young have retained
vestiges of the stripes, like the kittens of black cats, which are not in
the least striped when grown up.  Many species of deer, which when mature
are not spotted, are whilst young covered with white spots, as are likewise
some few species in the adult state.  So again the young in the whole
family of pigs (Suidae), and in certain rather distantly allied animals,
such as the tapir, are marked with dark longitudinal stripes; but here we
have a character apparently derived from an extinct progenitor, and now
preserved by the young alone.  In all such cases the old have had their
colours changed in the course of time, whilst the young have remained but
little altered, and this has been effected through the principle of
inheritance at corresponding ages.

This same principle applies to many birds belonging to various groups, in
which the young closely resemble each other, and differ much from their
respective adult parents.  The young of almost all the Gallinaceae, and of
some distantly allied birds such as ostriches, are covered with
longitudinally striped down; but this character points back to a state of
things so remote that it hardly concerns us.  Young cross-bills (Loxia)
have at first straight beaks like those of other finches, and in their
immature striated plumage they resemble the mature red-pole and female
siskin, as well as the young of the goldfinch, greenfinch, and some other
allied species.  The young of many kinds of buntings (Emberiza) resemble
one another, and likewise the adult state of the common bunting, E.
miliaria.  In almost the whole large group of thrushes the young have their
breasts spotted--a character which is retained throughout life by many
species, but is quite lost by others, as by the Turdus migratorius.  So
again with many thrushes, the feathers on the back are mottled before they
are moulted for the first time, and this character is retained for life by
certain eastern species.  The young of many species of shrikes (Lanius), of
some woodpeckers, and of an Indian pigeon (Chalcophaps indicus), are
transversely striped on the under surface; and certain allied species or
whole genera are similarly marked when adult.  In some closely-allied and
resplendent Indian cuckoos (Chrysococcyx), the mature species differ
considerably from one another in colour, but the young cannot be
distinguished.  The young of an Indian goose (Sarkidiornis melanonotus)
closely resemble in plumage an allied genus, Dendrocygna, when mature.  (1.
In regard to thrushes, shrikes, and woodpeckers, see Mr. Blyth, in
Charlesworth's 'Mag. of Nat. Hist.' vol. i. 1837, p. 304; also footnote to
his translation of Cuvier's 'Regne Animal,' p. 159.  I give the case of
Loxia on Mr. Blyth's information.  On thrushes, see also Audubon, 'Ornith.
Biog.' vol. ii. p. 195.  On Chrysococcyx and Chalcophaps, Blyth, as quoted
in Jerdon's 'Birds of India,' vol. iii. p. 485.  On Sarkidiornis, Blyth, in
'Ibis,' 1867, p. 175.)  Similar facts will hereafter be given in regard to
certain herons.  Young black-grouse (Tetrao tetrix) resemble the young as
well as the old of certain other species, for instance the red-grouse or T.
scoticus.  Finally, as Mr. Blyth, who has attended closely to this subject,
has well remarked, the natural affinities of many species are best
exhibited in their immature plumage; and as the true affinities of all
organic beings depend on their descent from a common progenitor, this
remark strongly confirms the belief that the immature plumage approximately
shews us the former or ancestral condition of the species.

Although many young birds, belonging to various families, thus give us a
glimpse of the plumage of their remote progenitors, yet there are many
other birds, both dull-coloured and bright-coloured, in which the young
closely resemble their parents.  In such cases the young of the different
species cannot resemble each other more closely than do the parents; nor
can they strikingly resemble allied forms when adult.  They give us but
little insight into the plumage of their progenitors, excepting in so far
that, when the young and the old are coloured in the same general manner
throughout a whole group of species, it is probable that their progenitors
were similarly coloured.

We may now consider the classes of cases, under which the differences and
resemblances between the plumage of the young and the old, in both sexes or
in one sex alone, may be grouped.  Rules of this kind were first enounced
by Cuvier; but with the progress of knowledge they require some
modification and amplification.  This I have attempted to do, as far as the
extreme complexity of the subject permits, from information derived from
various sources; but a full essay on this subject by some competent
ornithologist is much needed.  In order to ascertain to what extent each
rule prevails, I have tabulated the facts given in four great works,
namely, by Macgillivray on the birds of Britain, Audubon on those of North
America, Jerdon on those of India, and Gould on those of Australia.  I may
here premise, first, that the several cases or rules graduate into each
other; and secondly, that when the young are said to resemble their
parents, it is not meant that they are identically alike, for their colours
are almost always less vivid, and the feathers are softer and often of a
different shape.

RULES OR CLASSES OF CASES.

I.  When the adult male is more beautiful or conspicuous than the adult
female, the young of both sexes in their first plumage closely resemble the
adult female, as with the common fowl and peacock; or, as occasionally
occurs, they resemble her much more closely than they do the adult male.

II.  When the adult female is more conspicuous than the adult male, as
sometimes though rarely occurs, the young of both sexes in their first
plumage resemble the adult male.

III.  When the adult male resembles the adult female, the young of both
sexes have a peculiar first plumage of their own, as with the robin.

IV.  When the adult male resembles the adult female, the young of both
sexes in their first plumage resemble the adults, as with the kingfisher,
many parrots, crows, hedge-warblers.

V.  When the adults of both sexes have a distinct winter and summer
plumage, whether or not the male differs from the female, the young
resemble the adults of both sexes in their winter dress, or much more
rarely in their summer dress, or they resemble the females alone.  Or the
young may have an intermediate character; or again they may differ greatly
from the adults in both their seasonal plumages.

VI.  In some few cases the young in their first plumage differ from each
other according to sex; the young males resembling more or less closely the
adult males, and the young females more or less closely the adult females.

CLASS I.

In this class, the young of both sexes more or less closely resemble the
adult female, whilst the adult male differs from the adult female, often in
the most conspicuous manner.  Innumerable instances in all Orders could be
given; it will suffice to call to mind the common pheasant, duck, and
house-sparrow.  The cases under this class graduate into others.  Thus the
two sexes when adult may differ so slightly, and the young so slightly from
the adults, that it is doubtful whether such cases ought to come under the
present, or under the third or fourth classes.  So again the young of the
two sexes, instead of being quite alike, may differ in a slight degree from
each other, as in our sixth class.  These transitional cases, however, are
few, or at least are not strongly pronounced, in comparison with those
which come strictly under the present class.

The force of the present law is well shewn in those groups, in which, as a
general rule, the two sexes and the young are all alike; for when in these
groups the male does differ from the female, as with certain parrots,
kingfishers, pigeons, etc., the young of both sexes resemble the adult
female.  (2.  See, for instance, Mr. Gould's account ('Handbook to the
Birds of Australia,' vol. i. p. 133) of Cyanalcyon (one of the
Kingfishers), in which, however, the young male, though resembling the
adult female, is less brilliantly coloured.  In some species of Dacelo the
males have blue tails, and the females brown ones; and Mr. R.B. Sharpe
informs me that the tail of the young male of D. gaudichaudi is at first
brown.  Mr. Gould has described (ibid. vol. ii. pp. 14, 20, 37) the sexes
and the young of certain black Cockatoos and of the King Lory, with which
the same rule prevails.  Also Jerdon ('Birds of India,' vol. i. p. 260) on
the Palaeornis rosa, in which the young are more like the female than the
male.  See Audubon ('Ornithological Biography,' vol. ii. p. 475) on the two
sexes and the young of Columba passerina.)  We see the same fact exhibited
still more clearly in certain anomalous cases; thus the male of Heliothrix
auriculata (one of the humming-birds) differs conspicuously from the female
in having a splendid gorget and fine ear-tufts, but the female is
remarkable from having a much longer tail than that of the male; now the
young of both sexes resemble (with the exception of the breast being
spotted with bronze) the adult female in all other respects, including the
length of her tail, so that the tail of the male actually becomes shorter
as he reaches maturity, which is a most unusual circumstance.  (3.  I owe
this information to Mr. Gould, who shewed me the specimens; see also his
'Introduction to the Trochilidae,' 1861, p. 120.)  Again, the plumage of
the male goosander (Mergus merganser) is more conspicuously coloured than
that of the female, with the scapular and secondary wing-feathers much
longer; but differently from what occurs, as far as I know, in any other
bird, the crest of the adult male, though broader than that of the female,
is considerably shorter, being only a little above an inch in length; the
crest of the female being two and a half inches long.  Now the young of
both sexes entirely resemble the adult female, so that their crests are
actually of greater length, though narrower, than in the adult male.  (4.
Macgillivray, 'Hist. Brit. Birds,' vol. v. pp. 207-214.)

When the young and the females closely resemble each other and both differ
from the males, the most obvious conclusion is that the males alone have
been modified.  Even in the anomalous cases of the Heliothrix and Mergus,
it is probable that originally both adult sexes were furnished--the one
species with a much elongated tail, and the other with a much elongated
crest--these characters having since been partially lost by the adult males
from some unexplained cause, and transmitted in their diminished state to
their male offspring alone, when arrived at the corresponding age of
maturity.  The belief that in the present class the male alone has been
modified, as far as the differences between the male and the female
together with her young are concerned, is strongly supported by some
remarkable facts recorded by Mr. Blyth (5.  See his admirable paper in the
'Journal of the Asiatic Soc. of Bengal,' vol. xix. 1850, p. 223; see also
Jerdon, 'Birds of India,' vol. i. introduction, p. xxix.  In regard to
Tanysiptera, Prof. Schlegel told Mr. Blyth that he could distinguish
several distinct races, solely by comparing the adult males.), with respect
to closely-allied species which represent each other in distinct countries.
For with several of these representative species the adult males have
undergone a certain amount of change and can be distinguished; the females
and the young from the distinct countries being indistinguishable, and
therefore absolutely unchanged.  This is the case with certain Indian chats
(Thamnobia), with certain honey-suckers (Nectarinia), shrikes
(Tephrodornis), certain kingfishers (Tanysiptera), Kalij pheasants
(Gallophasis), and tree-partridges (Arboricola).

In some analogous cases, namely with birds having a different summer and
winter plumage, but with the two sexes nearly alike, certain closely-allied
species can easily be distinguished in their summer or nuptial plumage, yet
are indistinguishable in their winter as well as in their immature plumage.
This is the case with some of the closely-allied Indian wagtails or
Motacillae.  Mr. Swinhoe (6.  See also Mr. Swinhoe, in 'Ibis,' July 1863,
p. 131; and a previous paper, with an extract from a note by Mr. Blyth, in
'Ibis,' January, 1861, p. 25.) informs me that three species of Ardeola, a
genus of herons, which represent one another on separate continents, are
"most strikingly different" when ornamented with their summer plumes, but
are hardly, if at all, distinguishable during the winter.  The young also
of these three species in their immature plumage closely resemble the
adults in their winter dress.  This case is all the more interesting,
because with two other species of Ardeola both sexes retain, during the
winter and summer, nearly the same plumage as that possessed by the three
first species during the winter and in their immature state; and this
plumage, which is common to several distinct species at different ages and
seasons, probably shews us how the progenitors of the genus were coloured.
In all these cases, the nuptial plumage which we may assume was originally
acquired by the adult males during the breeding-season, and transmitted to
the adults of both sexes at the corresponding season, has been modified,
whilst the winter and immature plumages have been left unchanged.

The question naturally arises, how is it that in these latter cases the
winter plumage of both sexes, and in the former cases the plumage of the
adult females, as well as the immature plumage of the young, have not been
at all affected?  The species which represent each other in distinct
countries will almost always have been exposed to somewhat different
conditions, but we can hardly attribute to this action the modification of
the plumage in the males alone, seeing that the females and the young,
though similarly exposed, have not been affected.  Hardly any fact shews us
more clearly how subordinate in importance is the direct action of the
conditions of life, in comparison with the accumulation through selection
of indefinite variations, than the surprising difference between the sexes
of many birds; for both will have consumed the same food, and have been
exposed to the same climate.  Nevertheless we are not precluded from
believing that in the course of time new conditions may produce some direct
effect either on both sexes, or from their constitutional differences
chiefly on one sex.  We see only that this is subordinate in importance to
the accumulated results of selection.  Judging, however, from a wide-spread
analogy, when a species migrates into a new country (and this must precede
the formation of representative species), the changed conditions to which
they will almost always have been exposed will cause them to undergo a
certain amount of fluctuating variability.  In this case sexual selection,
which depends on an element liable to change--the taste or admiration of
the female--will have had new shades of colour or other differences to act
on and accumulate; and as sexual selection is always at work, it would
(from what we know of the results on domestic animals of man's
unintentional selection), be surprising if animals inhabiting separate
districts, which can never cross and thus blend their newly-acquired
characters, were not, after a sufficient lapse of time, differently
modified.  These remarks likewise apply to the nuptial or summer plumage,
whether confined to the males, or common to both sexes.

Although the females of the above closely-allied or representative species,
together with their young, differ hardly at all from one another, so that
the males alone can be distinguished, yet the females of most species
within the same genus obviously differ from each other.  The differences,
however, are rarely as great as between the males.  We see this clearly in
the whole family of the Gallinaceae:  the females, for instance, of the
common and Japan pheasant, and especially of the gold and Amherst pheasant
--of the silver pheasant and the wild fowl--resemble one another very
closely in colour, whilst the males differ to an extraordinary degree.  So
it is with the females of most of the Cotingidae, Fringillidae, and many
other families.  There can indeed be no doubt that, as a general rule, the
females have been less modified than the males.  Some few birds, however,
offer a singular and inexplicable exception; thus the females of Paradisea
apoda and P. papuana differ from each other more than do their respective
males (7.  Wallace, 'The Malay Archipelago,' vol. ii. 1869, p. 394.); the
female of the latter species having the under surface pure white, whilst
the female P. apoda is deep brown beneath.  So, again, as I hear from
Professor Newton, the males of two species of Oxynotus (shrikes), which
represent each other in the islands of Mauritius and Bourbon (8.  These
species are described with coloured figures, by M. F. Pollen, in 'Ibis,'
1866, p. 275.), differ but little in colour, whilst the females differ
much.  In the Bourbon species the female appears to have partially retained
an immature condition of plumage, for at first sight she "might be taken
for the young of the Mauritian species."  These differences may be compared
with those inexplicable ones, which occur independently of man's selection
in certain sub-breeds of the game-fowl, in which the females are very
different, whilst the males can hardly be distinguished.  (9.  'Variation
of Animals,' etc., vol. i. p. 251.)

As I account so largely by sexual selection for the differences between the
males of allied species, how can the differences between the females be
accounted for in all ordinary cases?  We need not here consider the species
which belong to distinct genera; for with these, adaptation to different
habits of life, and other agencies, will have come into play.  In regard to
the differences between the females within the same genus, it appears to me
almost certain, after looking through various large groups, that the chief
agent has been the greater or less transference to the female of the
characters acquired by the males through sexual selection.  In the several
British finches, the two sexes differ either very slightly or considerably;
and if we compare the females of the greenfinch, chaffinch, goldfinch,
bullfinch, crossbill, sparrow, etc., we shall see that they differ from one
another chiefly in the points in which they partially resemble their
respective males; and the colours of the males may safely be attributed to
sexual selection.  With many gallinaceous species the sexes differ to an
extreme degree, as with the peacock, pheasant, and fowl, whilst with other
species there has been a partial or even complete transference of character
from the male to the female.  The females of the several species of
Polyplectron exhibit in a dim condition, and chiefly on the tail, the
splendid ocelli of their males.  The female partridge differs from the male
only in the red mark on her breast being smaller; and the female wild
turkey only in her colours being much duller.  In the guinea-fowl the two
sexes are indistinguishable.  There is no improbability in the plain,
though peculiarly spotted plumage of this latter bird having been acquired
through sexual selection by the males, and then transmitted to both sexes;
for it is not essentially different from the much more beautifully spotted
plumage, characteristic of the males alone of the Tragopan pheasants.

It should be observed that, in some instances, the transference of
characters from the male to the female has been effected apparently at a
remote period, the male having subsequently undergone great changes,
without transferring to the female any of his later-gained characters.  For
instance, the female and the young of the black-grouse (Tetrao tetrix)
resemble pretty closely both sexes and the young of the red-grouse (T.
scoticus); and we may consequently infer that the black-grouse is descended
from some ancient species, of which both sexes were coloured in nearly the
same manner as the red-grouse.  As both sexes of this latter species are
more distinctly barred during the breeding-season than at any other time,
and as the male differs slightly from the female in his more strongly-
pronounced red and brown tints (10.  Macgillivray, 'History of British
Birds,' vol. i. pp. 172-174.), we may conclude that his plumage has been
influenced by sexual selection, at least to a certain extent.  If so, we
may further infer that nearly similar plumage of the female black-grouse
was similarly produced at some former period.  But since this period the
male black-grouse has acquired his fine black plumage, with his forked and
outwardly-curled tail-feathers; but of these characters there has hardly
been any transference to the female, excepting that she shews in her tail a
trace of the curved fork.

We may therefore conclude that the females of distinct though allied
species have often had their plumage rendered more or less different by the
transference in various degrees of characters acquired by the males through
sexual selection, both during former and recent times.  But it deserves
especial attention that brilliant colours have been transferred much more
rarely than other tints.  For instance, the male of the red-throated blue-
breast (Cyanecula suecica) has a rich blue breast, including a sub-
triangular red mark; now marks of nearly the same shape have been
transferred to the female, but the central space is fulvous instead of red,
and is surrounded by mottled instead of blue feathers.  The Gallinaceae
offer many analogous cases; for none of the species, such as partridges,
quails, guinea-fowls, etc., in which the colours of the plumage have been
largely transferred from the male to the female, are brilliantly coloured.
This is well exemplified with the pheasants, in which the male is generally
so much more brilliant than the female; but with the Eared and Cheer
pheasants (Crossoptilon auritum and Phasianus wallichii) the sexes closely
resemble each other and their colours are dull.  We may go so far as to
believe that if any part of the plumage in the males of these two pheasants
had been brilliantly coloured, it would not have been transferred to the
females.  These facts strongly support Mr. Wallace's view that with birds
which are exposed to much danger during incubation, the transference of
bright colours from the male to the female has been checked through natural
selection.  We must not, however, forget that another explanation, before
given, is possible; namely, that the males which varied and became bright,
whilst they were young and inexperienced, would have been exposed to much
danger, and would generally have been destroyed; the older and more
cautious males, on the other hand, if they varied in a like manner, would
not only have been able to survive, but would have been favoured in their
rivalry with other males.  Now variations occurring late in life tend to be
transmitted exclusively to the same sex, so that in this case extremely
bright tints would not have been transmitted to the females.  On the other
hand, ornaments of a less conspicuous kind, such as those possessed by the
Eared and Cheer pheasants, would not have been dangerous, and if they
appeared during early youth, would generally have been transmitted to both
sexes.

In addition to the effects of the partial transference of characters from
the males to the females, some of the differences between the females of
closely allied species may be attributed to the direct or definite action
of the conditions of life.  (11.  See, on this subject, chap. xxiii. in the
'Variation of Animals and Plants under Domestication.')  With the males,
any such action would generally have been masked by the brilliant colours
gained through sexual selection; but not so with the females.  Each of the
endless diversities in plumage which we see in our domesticated birds is,
of course, the result of some definite cause; and under natural and more
uniform conditions, some one tint, assuming that it was in no way
injurious, would almost certainly sooner or later prevail.  The free
intercrossing of the many individuals belonging to the same species would
ultimately tend to make any change of colour, thus induced, uniform in
character.

No one doubts that both sexes of many birds have had their colours adapted
for the sake of protection; and it is possible that the females alone of
some species may have been modified for this end.  Although it would be a
difficult, perhaps an impossible process, as shewn in the last chapter, to
convert one form of transmission into another through selection, there
would not be the least difficulty in adapting the colours of the female,
independently of those of the male, to surrounding objects, through the
accumulation of variations which were from the first limited in their
transmission to the female sex.  If the variations were not thus limited,
the bright tints of the male would be deteriorated or destroyed.  Whether
the females alone of many species have been thus specially modified, is at
present very doubtful.  I wish I could follow Mr. Wallace to the full
extent; for the admission would remove some difficulties.  Any variations
which were of no service to the female as a protection would be at once
obliterated, instead of being lost simply by not being selected, or from
free intercrossing, or from being eliminated when transferred to the male
and in any way injurious to him.  Thus the plumage of the female would be
kept constant in character.  It would also be a relief if we could admit
that the obscure tints of both sexes of many birds had been acquired and
preserved for the sake of protection,--for example, of the hedge-warbler or
kitty-wren (Accentor modularis and Troglodytes vulgaris), with respect to
which we have no sufficient evidence of the action of sexual selection.  We
ought, however, to be cautious in concluding that colours which appear to
us dull, are not attractive to the females of certain species; we should
bear in mind such cases as that of the common house-sparrow, in which the
male differs much from the female, but does not exhibit any bright tints.
No one probably will dispute that many gallinaceous birds which live on the
open ground, have acquired their present colours, at least in part, for the
sake of protection.  We know how well they are thus concealed; we know that
ptarmigans, whilst changing from their winter to their summer plumage, both
of which are protective, suffer greatly from birds of prey.  But can we
believe that the very slight differences in tints and markings between, for
instance, the female black-grouse and red-grouse serve as a protection?
Are partridges, as they are now coloured, better protected than if they had
resembled quails?  Do the slight differences between the females of the
common pheasant, the Japan and gold pheasants, serve as a protection, or
might not their plumages have been interchanged with impunity?  From what
Mr. Wallace has observed of the habits of certain gallinaceous birds in the
East, he thinks that such slight differences are beneficial.  For myself, I
will only say that I am not convinced.

Formerly when I was inclined to lay much stress on protection as accounting
for the duller colours of female birds, it occurred to me that possibly
both sexes and the young might aboriginally have been equally bright
coloured; but that subsequently, the females from the danger incurred
during incubation, and the young from being inexperienced, had been
rendered dull as a protection.  But this view is not supported by any
evidence, and is not probable; for we thus in imagination expose during
past times the females and the young to danger, from which it has
subsequently been necessary to shield their modified descendants.  We have,
also, to reduce, through a gradual process of selection, the females and
the young to almost exactly the same tints and markings, and to transmit
them to the corresponding sex and period of life.  On the supposition that
the females and the young have partaken during each stage of the process of
modification of a tendency to be as brightly coloured as the males, it is
also a somewhat strange fact that the females have never been rendered
dull-coloured without the young participating in the same change; for there
are no instances, as far as I can discover, of species with the females
dull and the young bright coloured.  A partial exception, however, is
offered by the young of certain woodpeckers, for they have "the whole upper
part of the head tinged with red," which afterwards either decreases into a
mere circular red line in the adults of both sexes, or quite disappears in
the adult females.  (12.  Audubon, 'Ornith. Biography,' vol. i. p. 193.
Macgillivray, 'History of British Birds,' vol. iii. p. 85.  See also the
case before given of Indopicus carlotta.)

Finally, with respect to our present class of cases, the most probable view
appears to be that successive variations in brightness or in other
ornamental characters, occurring in the males at a rather late period of
life have alone been preserved; and that most or all of these variations,
owing to the late period of life at which they appeared, have been from the
first transmitted only to the adult male offspring.  Any variations in
brightness occurring in the females or in the young, would have been of no
service to them, and would not have been selected; and moreover, if
dangerous, would have been eliminated.  Thus the females and the young will
either have been left unmodified, or (as is much more common) will have
been partially modified by receiving through transference from the males
some of his successive variations.  Both sexes have perhaps been directly
acted on by the conditions of life to which they have long been exposed:
but the females from not being otherwise much modified, will best exhibit
any such effects.  These changes and all others will have been kept uniform
by the free intercrossing of many individuals.  In some cases, especially
with ground birds, the females and the young may possibly have been
modified, independently of the males, for the sake of protection, so as to
have acquired the same dull-coloured plumage.

CLASS II.

WHEN THE ADULT FEMALE IS MORE CONSPICUOUS THAN THE ADULT MALE, THE YOUNG OF
BOTH SEXES IN THEIR FIRST PLUMAGE RESEMBLE THE ADULT MALE.

This class is exactly the reverse of the last, for the females are here
brighter coloured or more conspicuous than the males; and the young, as far
as they are known, resemble the adult males instead of the adult females.
But the difference between the sexes is never nearly so great as with many
birds in the first class, and the cases are comparatively rare.  Mr.
Wallace, who first called attention to the singular relation which exists
between the less bright colours of the males and their performing the
duties of incubation, lays great stress on this point (13.  'Westminster
Review,' July 1867, and A. Murray, 'Journal of Travel,' 1868, p. 83.), as a
crucial test that obscure colours have been acquired for the sake of
protection during the period of nesting.  A different view seems to me more
probable.  As the cases are curious and not numerous, I will briefly give
all that I have been able to find.

In one section of the genus Turnix, quail-like birds, the female is
invariably larger than the male (being nearly twice as large in one of the
Australian species), and this is an unusual circumstance with the
Gallinaceae.  In most of the species the female is more distinctly coloured
and brighter than the male (14.  For the Australian species, see Gould's
'Handbook,' etc., vol. ii. pp. 178, 180, 186, and 188.  In the British
Museum specimens of the Australian Plain-wanderer (Pedionomus torquatus)
may be seen, shewing similar sexual differences.), but in some few species
the sexes are alike.  In Turnix taigoor of India the male "wants the black
on the throat and neck, and the whole tone of the plumage is lighter and
less pronounced than that of the female."  The female appears to be
noisier, and is certainly much more pugnacious than the male; so that the
females and not the males are often kept by the natives for fighting, like
game-cocks.  As male birds are exposed by the English bird-catchers for a
decoy near a trap, in order to catch other males by exciting their rivalry,
so the females of this Turnix are employed in India.  When thus exposed the
females soon begin their "loud purring call, which can be heard a long way
off, and any females within ear-shot run rapidly to the spot, and commence
fighting with the caged bird."  In this way from twelve to twenty birds,
all breeding females, may be caught in the course of a single day.  The
natives assert that the females after laying their eggs associate in
flocks, and leave the males to sit on them.  There is no reason to doubt
the truth of this assertion, which is supported by some observations made
in China by Mr. Swinhoe.  (15.  Jerdon, 'Birds of India,' vol. iii. p. 596.
Mr. Swinhoe, in 'Ibis,' 1865, p. 542; 1866, pp. 131, 405.)  Mr. Blyth
believes, that the young of both sexes resemble the adult male.

[Fig. 62.  Rhynchaea capensis (from Brehm).]

The females of the three species of Painted Snipes (Rhynchaea, Fig. 62)
"are not only larger but much more richly coloured than the males."  (16.
Jerdon, 'Birds of India,' vol. iii. p. 677.)  With all other birds in which
the trachea differs in structure in the two sexes it is more developed and
complex in the male than in the female; but in the Rhynchaea australis it
is simple in the male, whilst in the female it makes four distinct
convolutions before entering the lungs.  (17.  Gould's 'Handbook to the
Birds of Australia,' vol. ii. p. 275.)  The female therefore of this
species has acquired an eminently masculine character.  Mr. Blyth
ascertained, by examining many specimens, that the trachea is not
convoluted in either sex of R. bengalensis, which species resembles R.
australis so closely, that it can hardly be distinguished except by its
shorter toes.  This fact is another striking instance of the law that
secondary sexual characters are often widely different in closely-allied
forms, though it is a very rare circumstance when such differences relate
to the female sex.  The young of both sexes of R. bengalensis in their
first plumage are said to resemble the mature male.  (18.  'The Indian
Field,' Sept. 1858, p. 3.)  There is also reason to believe that the male
undertakes the duty of incubation, for Mr. Swinhoe (19.  'Ibis,' 1866, p.
298.) found the females before the close of the summer associated in
flocks, as occurs with the females of the Turnix.

The females of Phalaropus fulicarius and P. hyperboreus are larger, and in
their summer plumage "more gaily attired than the males."  But the
difference in colour between the sexes is far from conspicuous.  According
to Professor Steenstrup, the male alone of P. fulicarius undertakes the
duty of incubation; this is likewise shewn by the state of his breast-
feathers during the breeding-season.  The female of the dotterel plover
(Eudromias morinellus) is larger than the male, and has the red and black
tints on the lower surface, the white crescent on the breast, and the
stripes over the eyes, more strongly pronounced.  The male also takes at
least a share in hatching the eggs; but the female likewise attends to the
young.  (20.  For these several statements, see Mr. Gould's 'Birds of Great
Britain.'  Prof. Newton informs me that he has long been convinced, from
his own observations and from those of others, that the males of the above-
named species take either the whole or a large share of the duties of
incubation, and that they "shew much greater devotion towards their young,
when in danger, than do the females."  So it is, as he informs me, with
Limosa lapponica and some few other Waders, in which the females are larger
and have more strongly contrasted colours than the males.)  I have not been
able to discover whether with these species the young resemble the adult
males more closely than the adult females; for the comparison is somewhat
difficult to make on account of the double moult.

Turning now to the ostrich Order:  the male of the common cassowary
(Casuarius galeatus) would be thought by any one to be the female, from his
smaller size and from the appendages and naked skin about his head being
much less brightly coloured; and I am informed by Mr. Bartlett that in the
Zoological Gardens, it is certainly the male alone who sits on the eggs and
takes care of the young.  (21.  The natives of Ceram (Wallace, 'Malay
Archipelago,' vol. ii. p. 150) assert that the male and female sit
alternately on the eggs; but this assertion, as Mr. Bartlett thinks, may be
accounted for by the female visiting the nest to lay her eggs.)  The female
is said by Mr. T.W. Wood (22.  The 'Student,' April 1870, p. 124.) to
exhibit during the breeding-season a most pugnacious disposition; and her
wattles then become enlarged and more brilliantly coloured.  So again the
female of one of the emus (Dromoeus irroratus) is considerably larger than
the male, and she possesses a slight top-knot, but is otherwise
indistinguishable in plumage.  She appears, however, "to have greater
power, when angry or otherwise excited, of erecting, like a turkey-cock,
the feathers of her neck and breast.  She is usually the more courageous
and pugilistic.  She makes a deep hollow guttural boom especially at night,
sounding like a small gong.  The male has a slenderer frame and is more
docile, with no voice beyond a suppressed hiss when angry, or a croak."  He
not only performs the whole duty of incubation, but has to defend the young
from their mother; "for as soon as she catches sight of her progeny she
becomes violently agitated, and notwithstanding the resistance of the
father appears to use her utmost endeavours to destroy them.  For months
afterwards it is unsafe to put the parents together, violent quarrels being
the inevitable result, in which the female generally comes off conqueror."
(23.  See the excellent account of the habits of this bird under
confinement, by Mr. A.W. Bennett, in 'Land and Water,' May 1868, p. 233.)
So that with this emu we have a complete reversal not only of the parental
and incubating instincts, but of the usual moral qualities of the two
sexes; the females being savage, quarrelsome, and noisy, the males gentle
and good.  The case is very different with the African ostrich, for the
male is somewhat larger than the female and has finer plumes with more
strongly contrasted colours; nevertheless he undertakes the whole duty of
incubation.  (24.  Mr. Sclater, on the incubation of the Struthiones,
'Proc. Zool. Soc.' June 9, 1863.  So it is with the Rhea darwinii:  Captain
Musters says ('At Home with the Patagonians,' 1871, p. 128), that the male
is larger, stronger and swifter than the female, and of slightly darker
colours; yet he takes sole charge of the eggs and of the young, just as
does the male of the common species of Rhea.)

I will specify the few other cases known to me, in which the female is more
conspicuously coloured than the male, although nothing is known about the
manner of incubation.  With the carrion-hawk of the Falkland Islands
(Milvago leucurus) I was much surprised to find by dissection that the
individuals, which had all their tints strongly pronounced, with the cere
and legs orange-coloured, were the adult females; whilst those with duller
plumage and grey legs were the males or the young.  In an Australian tree-
creeper (Climacteris erythrops) the female differs from the male in "being
adorned with beautiful, radiated, rufous markings on the throat, the male
having this part quite plain."  Lastly, in an Australian night-jar "the
female always exceeds the male in size and in the brilliance of her tints;
the males, on the other hand, have two white spots on the primaries more
conspicuous than in the female."  (25.  For the Milvago, see 'Zoology of
the Voyage of the "Beagle,"  Birds,' 1841, p. 16.  For the Climacteris and
night-jar (Eurostopodus), see Gould's 'Handbook to the Birds of Australia,'
vol. i. pp. 602 and 97.  The New Zealand shieldrake (Tadorna variegata)
offers a quite anomalous case; the head of the female is pure white, and
her back is redder than that of the male; the head of the male is of a rich
dark bronzed colour, and his back is clothed with finely pencilled slate-
coloured feathers, so that altogether he may be considered as the more
beautiful of the two.  He is larger and more pugnacious than the female,
and does not sit on the eggs.  So that in all these respects this species
comes under our first class of cases; but Mr. Sclater ('Proceedings of the
Zoological Society,' 1866, p. 150) was much surprised to observe that the
young of both sexes, when about three months old, resembled in their dark
heads and necks the adult males, instead of the adult females; so that it
would appear in this case that the females have been modified, whilst the
males and the young have retained a former state of plumage.)

We thus see that the cases in which female birds are more conspicuously
coloured than the males, with the young in their immature plumage
resembling the adult males instead of the adult females, as in the previous
class, are not numerous, though they are distributed in various Orders.
The amount of difference, also, between the sexes is incomparably less than
that which frequently occurs in the last class; so that the cause of the
difference, whatever it may have been, has here acted on the females either
less energetically or less persistently than on the males in the last
class.  Mr. Wallace believes that the males have had their colours rendered
less conspicuous for the sake of protection during the period of
incubation; but the difference between the sexes in hardly any of the
foregoing cases appears sufficiently great for this view to be safely
accepted.  In some of the cases, the brighter tints of the female are
almost confined to the lower surface, and the males, if thus coloured,
would not have been exposed to danger whilst sitting on the eggs.  It
should also be borne in mind that the males are not only in a slight degree
less conspicuously coloured than the females, but are smaller and weaker.
They have, moreover, not only acquired the maternal instinct of incubation,
but are less pugnacious and vociferous than the females, and in one
instance have simpler vocal organs.  Thus an almost complete transposition
of the instincts, habits, disposition, colour, size, and of some points of
structure, has been effected between the two sexes.

Now if we might assume that the males in the present class have lost some
of that ardour which is usual to their sex, so that they no longer search
eagerly for the females; or, if we might assume that the females have
become much more numerous than the males--and in the case of one Indian
Turnix the females are said to be "much more commonly met with than the
males" (26.  Jerdon, 'Birds of India,' vol. iii. p. 598.)--then it is not
improbable that the females would have been led to court the males, instead
of being courted by them.  This indeed is the case to a certain extent with
some birds, as we have seen with the peahen, wild turkey, and certain kinds
of grouse.  Taking as our guide the habits of most male birds, the greater
size and strength as well as the extraordinary pugnacity of the females of
the Turnix and emu, must mean that they endeavour to drive away rival
females, in order to gain possession of the male; and on this view all the
facts become clear; for the males would probably be most charmed or excited
by the females which were the most attractive to them by their bright
colours, other ornaments, or vocal powers.  Sexual selection would then do
its work, steadily adding to the attractions of the females; the males and
the young being left not at all, or but little modified.

CLASS III.

WHEN THE ADULT MALE RESEMBLES THE ADULT FEMALE, THE YOUNG OF BOTH SEXES
HAVE A PECULIAR FIRST PLUMAGE OF THEIR OWN.

In this class the sexes when adult resemble each other, and differ from the
young.  This occurs with many birds of many kinds.  The male robin can
hardly be distinguished from the female, but the young are widely
different, with their mottled dusky-olive and brown plumage.  The male and
female of the splendid scarlet ibis are alike, whilst the young are brown;
and the scarlet colour, though common to both sexes, is apparently a sexual
character, for it is not well developed in either sex under confinement;
and a loss of colour often occurs with brilliant males when they are
confined.  With many species of herons the young differ greatly from the
adults; and the summer plumage of the latter, though common to both sexes,
clearly has a nuptial character.  Young swans are slate-coloured, whilst
the mature birds are pure white; but it would be superfluous to give
additional instances.  These differences between the young and the old
apparently depend, as in the last two classes, on the young having retained
a former or ancient state of plumage, whilst the old of both sexes have
acquired a new one.  When the adults are bright coloured, we may conclude
from the remarks just made in relation to the scarlet ibis and to many
herons, and from the analogy of the species in the first class, that such
colours have been acquired through sexual selection by the nearly mature
males; but that, differently from what occurs in the first two classes, the
transmission, though limited to the same age, has not been limited to the
same sex.  Consequently, the sexes when mature resemble each other and
differ from the young.

CLASS IV.

WHEN THE ADULT MALE RESEMBLES THE ADULT FEMALE, THE YOUNG OF BOTH SEXES IN
THEIR FIRST PLUMAGE RESEMBLE THE ADULTS.

In this class the young and the adults of both sexes, whether brilliantly
or obscurely coloured, resemble each other.  Such cases are, I think, more
common than those in the last class.  We have in England instances in the
kingfisher, some woodpeckers, the jay, magpie, crow, and many small dull-
coloured birds, such as the hedge-warbler or kitty-wren.  But the
similarity in plumage between the young and the old is never complete, and
graduates away into dissimilarity.  Thus the young of some members of the
kingfisher family are not only less vividly coloured than the adults, but
many of the feathers on the lower surface are edged with brown (27.
Jerdon, 'Birds of India,' vol. i. pp. 222, 228.  Gould's 'Handbook to the
Birds of Australia,' vol. i. pp. 124, 130.),--a vestige probably of a
former state of the plumage.  Frequently in the same group of birds, even
within the same genus, for instance in an Australian genus of parrakeets
(Platycercus), the young of some species closely resemble, whilst the young
of other species differ considerably, from their parents of both sexes,
which are alike.  (28.  Gould, ibid. vol. ii. pp. 37, 46, 56.)  Both sexes
and the young of the common jay are closely similar; but in the Canada jay
(Perisoreus canadensis) the young differ so much from their parents that
they were formerly described as distinct species.  (29.  Audubon, 'Ornith.
Biography,' vol. ii. p. 55.)

I may remark before proceeding that, under the present and next two classes
of cases, the facts are so complex and the conclusions so doubtful, that
any one who feels no especial interest in the subject had better pass them
over.

The brilliant or conspicuous colours which characterise many birds in the
present class, can rarely or never be of service to them as a protection;
so that they have probably been gained by the males through sexual
selection, and then transferred to the females and the young.  It is,
however, possible that the males may have selected the more attractive
females; and if these transmitted their characters to their offspring of
both sexes, the same results would follow as from the selection of the more
attractive males by the females.  But there is evidence that this
contingency has rarely, if ever, occurred in any of those groups of birds
in which the sexes are generally alike; for, if even a few of the
successive variations had failed to be transmitted to both sexes, the
females would have slightly exceeded the males in beauty.  Exactly the
reverse occurs under nature; for, in almost every large group in which the
sexes generally resemble each other, the males of some few species are in a
slight degree more brightly coloured than the females.  It is again
possible that the females may have selected the more beautiful males, these
males having reciprocally selected the more beautiful females; but it is
doubtful whether this double process of selection would be likely to occur,
owing to the greater eagerness of one sex than the other, and whether it
would be more efficient than selection on one side alone.  It is,
therefore, the most probable view that sexual selection has acted, in the
present class, as far as ornamental characters are concerned, in accordance
with the general rule throughout the animal kingdom, that is, on the males;
and that these have transmitted their gradually-acquired colours, either
equally or almost equally, to their offspring of both sexes.

Another point is more doubtful, namely, whether the successive variations
first appeared in the males after they had become nearly mature, or whilst quite
young.  In either case sexual selection must have acted on the male when he
had to compete with rivals for the possession of the female; and in both
cases the characters thus acquired have been transmitted to both sexes and
all ages.  But these characters if acquired by the males when adult, may
have been transmitted at first to the adults alone, and at some subsequent
period transferred to the young.  For it is known that, when the law of
inheritance at corresponding ages fails, the offspring often inherit
characters at an earlier age than that at which they first appeared in
their parents.  (30.  'Variation of Animals and Plants under
Domestication,' vol. ii. p. 79.)  Cases apparently of this kind have been
observed with birds in a state of nature.  For instance Mr. Blyth has seen
specimens of Lanius rufus and of Colymbus glacialis which had assumed
whilst young, in a quite anomalous manner, the adult plumage of their
parents.  (31.  'Charlesworth's Magazine of Natural History,' vol. i. 1837,
pp. 305, 306.)  Again, the young of the common swan (Cygnus olor) do not
cast off their dark feathers and become white until eighteen months or two
years old; but Dr. F. Forel has described the case of three vigorous young
birds, out of a brood of four, which were born pure white.  These young
birds were not albinos, as shewn by the colour of their beaks and legs,
which nearly resembled the same parts in the adults.  (32.  'Bulletin de la
Soc. Vaudoise des Sc. Nat.' vol. x. 1869, p. 132.  The young of the Polish
swan, Cygnus immutabilis of Yarrell, are always white; but this species, as
Mr. Sclater informs me, is believed to be nothing more than a variety of
the domestic swan (Cygnus olor).)

It may be worth while to illustrate the above three modes by which, in the
present class, the two sexes and the young may have come to resemble each
other, by the curious case of the genus Passer.  (33.  I am indebted to Mr.
Blyth for information in regard to this genus.  The sparrow of Palestine
belongs to the sub-genus Petronia.)  In the house-sparrow (P. domesticus)
the male differs much from the female and from the young.  The young and
the females are alike, and resemble to a large extent both sexes and the
young of the sparrow of Palestine (P. brachydactylus), as well as of some
allied species.  We may therefore assume that the female and young of the
house-sparrow approximately shew us the plumage of the progenitor of the
genus.  Now with the tree-sparrow (P. montanus) both sexes and the young
closely resemble the male of the house-sparrow; so that they have all been
modified in the same manner, and all depart from the typical colouring of
their early progenitor.  This may have been effected by a male ancestor of
the tree-sparrow having varied, firstly, when nearly mature; or, secondly,
whilst quite young, and by having in either case transmitted his modified
plumage to the females and the young; or, thirdly, he may have varied when
adult and transmitted his plumage to both adult sexes, and, owing to the
failure of the law of inheritance at corresponding ages, at some subsequent
period to his young.

It is impossible to decide which of these three modes has generally
prevailed throughout the present class of cases.  That the males varied
whilst young, and transmitted their variations to their offspring of both
sexes, is the most probable.  I may here add that I have, with little
success, endeavoured, by consulting various works, to decide how far the
period of variation in birds has generally determined the transmission of
characters to one sex or to both.  The two rules, often referred to
(namely, that variations occurring late in life are transmitted to one and
the same sex, whilst those which occur early in life are transmitted to
both sexes), apparently hold good in the first (34.  For instance, the
males of Tanagra aestiva and Fringilla cyanea require three years, the male
of Fringilla ciris four years, to complete their beautiful plumage.  (See
Audubon, 'Ornith. Biography,' vol. i. pp. 233, 280, 378).  The Harlequin
duck takes three years (ibid. vol. iii. p. 614).  The male of the Gold
pheasant, as I hear from Mr. Jenner Weir, can be distinguished from the
female when about three months old, but he does not acquire his full
splendour until the end of the September in the following year.), second,
and fourth classes of cases; but they fail in the third, often in the fifth
(35.  Thus the Ibis tantalus and Grus americanus take four years, the
Flamingo several years, and the Ardea ludovicana two years, before they
acquire their perfect plumage.  See Audubon, ibid. vol. i. p. 221; vol.
iii. pp. 133, 139, 211.), and in the sixth small class.  They apply,
however, as far as I can judge, to a considerable majority of the species;
and we must not forget the striking generalisation by Dr. W. Marshall with
respect to the protuberances on the heads of birds.  Whether or not the two
rules generally hold good, we may conclude from the facts given in the
eighth chapter, that the period of variation is one important element in
determining the form of transmission.

With birds it is difficult to decide by what standard we ought to judge of
the earliness or lateness of the period of variation, whether by the age in
reference to the duration of life, or to the power of reproduction, or to
the number of moults through which the species passes.  The moulting of
birds, even within the same family, sometimes differs much without any
assignable cause.  Some birds moult so early, that nearly all the body
feathers are cast off before the first wing-feathers are fully grown; and
we cannot believe that this was the primordial state of things.  When the
period of moulting has been accelerated, the age at which the colours of
the adult plumage are first developed will falsely appear to us to be
earlier than it really is.  This may be illustrated by the practice
followed by some bird-fanciers, who pull out a few feathers from the breast
of nestling bullfinches, and from the head or neck of young gold-pheasants,
in order to ascertain their sex; for in the males, these feathers are
immediately replaced by coloured ones.  (36.  Mr. Blyth, in Charlesworth's
'Magazine of Natural History,' vol. i. 1837, p. 300.  Mr. Bartlett has
informed me in regard to gold pheasants.)  The actual duration of life is
known in but few birds, so that we can hardly judge by this standard.  And,
with reference to the period at which the power of reproduction is gained,
it is a remarkable fact that various birds occasionally breed whilst
retaining their immature plumage.  (37.  I have noticed the following cases
in Audubon's 'Ornith. Biography.'  The redstart of America (Muscapica
ruticilla, vol. i. p. 203).  The Ibis tantalus takes four years to come to
full maturity, but sometimes breeds in the second year (vol. iii. p. 133).
The Grus americanus takes the same time, but breeds before acquiring its
full plumage (vol. iii. p. 211).  The adults of Ardea caerulea are blue,
and the young white; and white, mottled, and mature blue birds may all be
seen breeding together (vol. iv. p. 58):  but Mr. Blyth informs me that
certain herons apparently are dimorphic, for white and coloured individuals
of the same age may be observed.  The Harlequin duck (Anas histrionica,
Linn.) takes three years to acquire its full plumage, though many birds
breed in the second year (vol. iii. p. 614).  The White-headed Eagle (Falco
leucocephalus, vol. iii. p. 210) is likewise known to breed in its immature
state.  Some species of Oriolus (according to Mr. Blyth and Mr. Swinhoe, in
'Ibis,' July 1863, p. 68) likewise breed before they attain their full
plumage.)

The fact of birds breeding in their immature plumage seems opposed to the
belief that sexual selection has played as important a part, as I believe
it has, in giving ornamental colours, plumes, etc., to the males, and, by
means of equal transmission, to the females of many species.  The objection
would be a valid one, if the younger and less ornamented males were as
successful in winning females and propagating their kind, as the older and
more beautiful males.  But we have no reason to suppose that this is the
case.  Audubon speaks of the breeding of the immature males of Ibis
tantalus as a rare event, as does Mr. Swinhoe, in regard to the immature
males of Oriolus.  (38.  See footnote 37 above.)  If the young of any
species in their immature plumage were more successful in winning partners
than the adults, the adult plumage would probably soon be lost, as the
males would prevail, which retained their immature dress for the longest
period, and thus the character of the species would ultimately be modified.
(39.  Other animals, belonging to quite distinct classes, are either
habitually or occasionally capable of breeding before they have fully
acquired their adult characters.  This is the case with the young males of
the salmon.  Several amphibians have been known to breed whilst retaining
their larval structure.  Fritz Mueller has shewn ('Facts and arguments for
Darwin,' Eng. trans. 1869, p. 79) that the males of several amphipod
crustaceans become sexually mature whilst young; and I infer that this is a
case of premature breeding, because they have not as yet acquired their
fully-developed claspers.  All such facts are highly interesting, as
bearing on one means by which species may undergo great modifications of
character.)  If, on the other hand, the young never succeeded in obtaining
a female, the habit of early reproduction would perhaps be sooner or later
eliminated, from being superfluous and entailing waste of power.

The plumage of certain birds goes on increasing in beauty during many years
after they are fully mature; this is the case with the train of the
peacock, with some of the birds of paradise, and with the crest and plumes
of certain herons, for instance, the Ardea ludovicana.  (40.  Jerdon,
'Birds of India,' vol. iii. p. 507, on the peacock.  Dr. Marshall thinks
that the older and more brilliant males of birds of paradise, have an
advantage over the younger males; see 'Archives Neerlandaises,' tom. vi.
1871.--On Ardea, Audubon, ibid. vol. iii. p. 139.)  But it is doubtful
whether the continued development of such feathers is the result of the
selection of successive beneficial variations (though this is the most
probable view with birds of paradise) or merely of continuous growth.  Most
fishes continue increasing in size, as long as they are in good health and
have plenty of food; and a somewhat similar law may prevail with the plumes
of birds.

CLASS V.

WHEN THE ADULTS OF BOTH SEXES HAVE A DISTINCT WINTER AND SUMMER PLUMAGE,
WHETHER OR NOT THE MALE DIFFERS FROM THE FEMALE, THE YOUNG RESEMBLE THE
ADULTS OF BOTH SEXES IN THEIR WINTER DRESS, OR MUCH MORE RARELY IN THEIR
SUMMER DRESS, OR THEY RESEMBLE THE FEMALES ALONE.  OR THE YOUNG MAY HAVE AN
INTERMEDIATE CHARACTER; OR, AGAIN, THEY MAY DIFFER GREATLY FROM THE ADULTS
IN BOTH THEIR SEASONAL PLUMAGES.

The cases in this class are singularly complex; nor is this surprising, as
they depend on inheritance, limited in a greater or less degree in three
different ways, namely, by sex, age, and the season of the year.  In some
cases the individuals of the same species pass through at least five
distinct states of plumage.  With the species, in which the male differs
from the female during the summer season alone, or, which is rarer, during
both seasons (41.  For illustrative cases, see vol. iv. of Macgillivray's
'History of British Birds;' on Tringa, etc., pp. 229, 271; on the Machetes,
p. 172; on the Charadrius hiaticula, p. 118; on the Charadrius pluvialis,
p. 94.), the young generally resemble the females,--as with the so-called
goldfinch of North America, and apparently with the splendid Maluri of
Australia.  (42.  For the goldfinch of N. America, Fringilla tristis,
Linn., see Audubon, 'Ornithological Biography,' vol. i. p. 172.  For the
Maluri, Gould's 'Handbook of the Birds of Australia,' vol. i. p. 318.)
With those species, the sexes of which are alike during both the summer and
winter, the young may resemble the adults, firstly, in their winter dress;
secondly, and this is of much rarer occurrence, in their summer dress;
thirdly, they may be intermediate between these two states; and, fourthly,
they may differ greatly from the adults at all seasons.  We have an
instance of the first of these four cases in one of the egrets of India
(Buphus coromandus), in which the young and the adults of both sexes are
white during the winter, the adults becoming golden-buff during the summer.

With the gaper (Anastomus oscitans) of India we have a similar case, but
the colours are reversed:  for the young and the adults of both sexes are
grey and black during the winter, the adults becoming white during the
summer.  (43.  I am indebted to Mr. Blyth for information as to the Buphus;
see also Jerdon, 'Birds of India,' vol. iii. p. 749.  On the Anastomus, see
Blyth, in 'Ibis,' 1867, p. 173.)  As an instance of the second case, the
young of the razor-bill (Alca torda, Linn.), in an early state of plumage,
are coloured like the adults during the summer; and the young of the white-
crowned sparrow of North America (Fringilla leucophrys), as soon as
fledged, have elegant white stripes on their heads, which are lost by the
young and the old during the winter.  (44.  On the Alca, see Macgillivray,
'Hist. Brit. Birds,' vol. v. p. 347.  On the Fringilla leucophrys, Audubon,
ibid. vol. ii. p. 89.  I shall have hereafter to refer to the young of
certain herons and egrets being white.)  With respect to the third case,
namely, that of the young having an intermediate character between the
summer and winter adult plumages, Yarrell (45.  'History of British Birds,'
vol. i. 1839, p. 159.) insists that this occurs with many waders.  Lastly,
in regard to the young differing greatly from both sexes in their adult
summer and winter plumages, this occurs with some herons and egrets of
North America and India,--the young alone being white.

I will make only a few remarks on these complicated cases.  When the young
resemble the females in their summer dress, or the adults of both sexes in
their winter dress, the cases differ from those given under Classes I. and
III. only in the characters originally acquired by the males during the
breeding-season, having been limited in their transmission to the
corresponding season.  When the adults have a distinct summer and winter
plumage, and the young differ from both, the case is more difficult to
understand.  We may admit as probable that the young have retained an
ancient state of plumage; we can account by sexual selection for the summer
or nuptial plumage of the adults, but how are we to account for their
distinct winter plumage?  If we could admit that this plumage serves in all
cases as a protection, its acquirement would be a simple affair; but there
seems no good reason for this admission.  It may be suggested that the
widely different conditions of life during the winter and summer have acted
in a direct manner on the plumage; this may have had some effect, but I
have not much confidence in so great a difference as we sometimes see
between the two plumages, having been thus caused.  A more probable
explanation is, that an ancient style of plumage, partially modified
through the transference of some characters from the summer plumage, has
been retained by the adults during the winter.  Finally, all the cases in
our present class apparently depend on characters acquired by the adult
males, having been variously limited in their transmission according to
age, season, and sex; but it would not be worth while to attempt to follow
out these complex relations.

CLASS VI.

THE YOUNG IN THEIR FIRST PLUMAGE DIFFER FROM EACH OTHER ACCORDING TO SEX;
THE YOUNG MALES RESEMBLING MORE OR LESS CLOSELY THE ADULT MALES, AND THE
YOUNG FEMALES MORE OR LESS CLOSELY THE ADULT FEMALES.

The cases in the present class, though occurring in various groups, are not
numerous; yet it seems the most natural thing that the young should at
first somewhat resemble the adults of the same sex, and gradually become
more and more like them.  The adult male blackcap (Sylvia atricapilla) has
a black head, that of the female being reddish-brown; and I am informed by
Mr. Blyth, that the young of both sexes can be distinguished by this
character even as nestlings.  In the family of thrushes an unusual number
of similar cases have been noticed; thus, the male blackbird (Turdus
merula) can be distinguished in the nest from the female.  The two sexes of
the mocking bird (Turdus polyglottus, Linn.) differ very little from each
other, yet the males can easily be distinguished at a very early age from
the females by showing more pure white.  (46.  Audubon, 'Ornith.
Biography,' vol. i. p. 113.)  The males of a forest-thrush and of a rock-
thrush (Orocetes erythrogastra and Petrocincla cyanea) have much of their
plumage of a fine blue, whilst the females are brown; and the nestling
males of both species have their main wing and tail-feathers edged with
blue whilst those of the female are edged with brown.  (47.  Mr. C.A.
Wright, in 'Ibis,' vol. vi. 1864, p. 65.  Jerdon, 'Birds of India,' vol. i.
p. 515.  See also on the blackbird, Blyth in Charlesworth's 'Magazine of
Natural History,' vol. i. 1837, p. 113.)  In the young blackbird the wing-
feathers assume their mature character and become black after the others;
on the other hand, in the two species just named the wing-feathers become
blue before the others.  The most probable view with reference to the cases
in the present class is that the males, differently from what occurs in
Class I., have transmitted their colours to their male offspring at an
earlier age than that at which they were first acquired; for, if the males
had varied whilst quite young, their characters would probably have been
transmitted to both sexes.  (48.  The following additional cases may be
mentioned; the young males of Tanagra rubra can be distinguished from the
young females (Audubon, 'Ornith. Biography,' vol. iv. p. 392), and so it is
within the nestlings of a blue nuthatch, Dendrophila frontalis of India
(Jerdon, 'Birds of India,' vol. i. p. 389).  Mr. Blyth also informs me that
the sexes of the stonechat, Saxicola rubicola, are distinguishable at a
very early age.  Mr. Salvin gives ('Proc. Zoolog. Soc.' 1870, p. 206) the
case of a humming-bird, like the following one of Eustephanus.)

In Aithurus polytmus, a humming-bird, the male is splendidly coloured black
and green, and two of the tail-feathers are immensely lengthened; the
female has an ordinary tail and inconspicuous colours; now the young males,
instead of resembling the adult female, in accordance with the common rule,
begin from the first to assume the colours proper to their sex, and their
tail-feathers soon become elongated.  I owe this information to Mr. Gould,
who has given me the following more striking and as yet unpublished case.
Two humming-birds belonging to the genus Eustephanus, both beautifully
coloured, inhabit the small island of Juan Fernandez, and have always been
ranked as specifically distinct.  But it has lately been ascertained that
the one which is of a rich chestnut-brown colour with a golden-red head, is
the male, whilst the other which is elegantly variegated with green and
white with a metallic green head is the female.  Now the young from the
first somewhat resemble the adults of the corresponding sex, the
resemblance gradually becoming more and more complete.

In considering this last case, if as before we take the plumage of the
young as our guide, it would appear that both sexes have been rendered
beautiful independently; and not that one sex has partially transferred its
beauty to the other.  The male apparently has acquired his bright colours
through sexual selection in the same manner as, for instance, the peacock
or pheasant in our first class of cases; and the female in the same manner
as the female Rhynchaea or Turnix in our second class of cases.  But there
is much difficulty in understanding how this could have been effected at
the same time with the two sexes of the same species.  Mr. Salvin states,
as we have seen in the eighth chapter, that with certain humming-birds the
males greatly exceed the females in number, whilst with other species
inhabiting the same country the females greatly exceed the males.  If,
then, we might assume that during some former lengthened period the males
of the Juan Fernandez species had greatly exceeded the females in number,
but that during another lengthened period the females had far exceeded the
males, we could understand how the males at one time, and the females at
another, might have been rendered beautiful by the selection of the
brighter coloured individuals of either sex; both sexes transmitting their
characters to their young at a rather earlier age than usual.  Whether this
is the true explanation I will not pretend to say; but the case is too
remarkable to be passed over without notice.

We have now seen in all six classes, that an intimate relation exists
between the plumage of the young and the adults, either of one sex or both.
These relations are fairly well explained on the principle that one sex--
this being in the great majority of cases the male--first acquired through
variation and sexual selection bright colours or other ornaments, and
transmitted them in various ways, in accordance with the recognised laws of
inheritance.  Why variations have occurred at different periods of life,
even sometimes with species of the same group, we do not know, but with
respect to the form of transmission, one important determining cause seems
to be the age at which the variations first appear.

From the principle of inheritance at corresponding ages, and from any
variations in colour which occurred in the males at an early age not being
then selected--on the contrary being often eliminated as dangerous--whilst
similar variations occurring at or near the period of reproduction have
been preserved, it follows that the plumage of the young will often have
been left unmodified, or but little modified.  We thus get some insight
into the colouring of the progenitors of our existing species.  In a vast
number of species in five out of our six classes of cases, the adults of
one sex or of both are bright coloured, at least during the breeding-
season, whilst the young are invariably less brightly coloured than the
adults, or are quite dull coloured; for no instance is known, as far as I
can discover, of the young of dull-coloured species displaying bright
colours, or of the young of bright-coloured species being more brilliant
than their parents.  In the fourth class, however, in which the young and
the old resemble each other, there are many species (though by no means
all), of which the young are bright-coloured, and as these form old groups,
we may infer that their early progenitors were likewise bright.  With this
exception, if we look to the birds of the world, it appears that their
beauty has been much increased since that period, of which their immature
plumage gives us a partial record.

ON THE COLOUR OF THE PLUMAGE IN RELATION TO PROTECTION.

It will have been seen that I cannot follow Mr. Wallace in the belief that
dull colours, when confined to the females, have been in most cases
specially gained for the sake of protection.  There can, however, be no
doubt, as formerly remarked, that both sexes of many birds have had their
colours modified, so as to escape the notice of their enemies; or in some
instances, so as to approach their prey unobserved, just as owls have had
their plumage rendered soft, that their flight may not be overheard.  Mr.
Wallace remarks (49.  'Westminster Review,' July 1867, p. 5.) that "it is
only in the tropics, among forests which never lose their foliage, that we
find whole groups of birds, whose chief colour is green."  It will be
admitted by every one, who has ever tried, how difficult it is to
distinguish parrots in a leaf-covered tree.  Nevertheless, we must remember
that many parrots are ornamented with crimson, blue, and orange tints,
which can hardly be protective.  Woodpeckers are eminently arboreal, but
besides green species, there are many black, and black-and-white kinds--all
the species being apparently exposed to nearly the same dangers.  It is
therefore probable that with tree-haunting birds, strongly-pronounced
colours have been acquired through sexual selection, but that a green tint
has been acquired oftener than any other, from the additional advantage of
protection.

In regard to birds which live on the ground, every one admits that they are
coloured so as to imitate the surrounding surface.  How difficult it is to
see a partridge, snipe, woodcock, certain plovers, larks, and night-jars
when crouched on ground.  Animals inhabiting deserts offer the most
striking cases, for the bare surface affords no concealment, and nearly all
the smaller quadrupeds, reptiles, and birds depend for safety on their
colours.  Mr. Tristram has remarked in regard to the inhabitants of the
Sahara, that all are protected by their "isabelline or sand-colour."  (50.
'Ibis,' 1859, vol. i. p. 429, et seq.  Dr. Rohlfs, however, remarks to me
in a letter that according to his experience of the Sahara, this statement
is too strong.)  Calling to my recollection the desert-birds of South
America, as well as most of the ground-birds of Great Britain, it appeared
to me that both sexes in such cases are generally coloured nearly alike.
Accordingly, I applied to Mr. Tristram with respect to the birds of the
Sahara, and he has kindly given me the following information.  There are
twenty-six species belonging to fifteen genera, which manifestly have their
plumage coloured in a protective manner; and this colouring is all the more
striking, as with most of these birds it differs from that of their
congeners.  Both sexes of thirteen out of the twenty-six species are
coloured in the same manner; but these belong to genera in which this rule
commonly prevails, so that they tell us nothing about the protective
colours being the same in both sexes of desert-birds.  Of the other
thirteen species, three belong to genera in which the sexes usually differ
from each other, yet here they have the sexes alike.  In the remaining ten
species, the male differs from the female; but the difference is confined
chiefly to the under surface of the plumage, which is concealed when the
bird crouches on the ground; the head and back being of the same sand-
coloured hue in the two sexes.  So that in these ten species the upper
surfaces of both sexes have been acted on and rendered alike, through
natural selection, for the sake of protection; whilst the lower surfaces of
the males alone have been diversified, through sexual selection, for the
sake of ornament.  Here, as both sexes are equally well protected, we
clearly see that the females have not been prevented by natural selection
from inheriting the colours of their male parents; so that we must look to
the law of sexually-limited transmission.

In all parts of the world both sexes of many soft-billed birds, especially
those which frequent reeds or sedges, are obscurely coloured.  No doubt if
their colours had been brilliant, they would have been much more
conspicuous to their enemies; but whether their dull tints have been
specially gained for the sake of protection seems, as far as I can judge,
rather doubtful.  It is still more doubtful whether such dull tints can
have been gained for the sake of ornament.  We must, however, bear in mind
that male birds, though dull-coloured, often differ much from their females
(as with the common sparrow), and this leads to the belief that such
colours have been gained through sexual selection, from being attractive.
Many of the soft-billed birds are songsters; and a discussion in a former
chapter should not be forgotten, in which it was shewn that the best
songsters are rarely ornamented with bright tints.  It would appear that
female birds, as a general rule, have selected their mates either for their
sweet voices or gay colours, but not for both charms combined.  Some
species, which are manifestly coloured for the sake of protection, such as
the jack-snipe, woodcock, and night-jar, are likewise marked and shaded,
according to our standard of taste, with extreme elegance.  In such cases
we may conclude that both natural and sexual selection have acted
conjointly for protection and ornament.  Whether any bird exists which does
not possess some special attraction, by which to charm the opposite sex,
may be doubted.  When both sexes are so obscurely coloured that it would be
rash to assume the agency of sexual selection, and when no direct evidence
can be advanced shewing that such colours serve as a protection, it is best
to own complete ignorance of the cause, or, which comes to nearly the same
thing, to attribute the result to the direct action of the conditions of
life.

Both sexes of many birds are conspicuously, though not brilliantly
coloured, such as the numerous black, white, or piebald species; and these
colours are probably the result of sexual selection.  With the common
blackbird, capercailzie, blackcock, black scoter-duck (Oidemia), and even
with one of the birds of paradise (Lophorina atra), the males alone are
black, whilst the females are brown or mottled; and there can hardly be a
doubt that blackness in these cases has been a sexually selected character.
Therefore it is in some degree probable that the complete or partial
blackness of both sexes in such birds as crows, certain cockatoos, storks,
and swans, and many marine birds, is likewise the result of sexual
selection, accompanied by equal transmission to both sexes; for blackness
can hardly serve in any case as a protection.  With several birds, in which
the male alone is black, and in others in which both sexes are black, the
beak or skin about the head is brightly coloured, and the contrast thus
afforded adds much to their beauty; we see this in the bright yellow beak
of the male blackbird, in the crimson skin over the eyes of the blackcock
and capercailzie, in the brightly and variously coloured beak of the
scoter-drake (Oidemia), in the red beak of the chough (Corvus graculus,
Linn.), of the black swan, and the black stork.  This leads me to remark
that it is not incredible that toucans may owe the enormous size of their
beaks to sexual selection, for the sake of displaying the diversified and
vivid stripes of colour, with which these organs are ornamented.  (51.  No
satisfactory explanation has ever been offered of the immense size, and
still less of the bright colours, of the toucan's beak.  Mr. Bates ('The
Naturalist on the Amazons,' vol. ii. 1863, p. 341) states that they use
their beaks for reaching fruit at the extreme tips of the branches; and
likewise, as stated by other authors, for extracting eggs and young birds
from the nests of other birds.  But, as Mr. Bates admits, the beak "can
scarcely be considered a very perfectly-formed instrument for the end to
which it is applied."  The great bulk of the beak, as shewn by its breadth,
depth, as well as length, is not intelligible on the view, that it serves
merely as an organ of prehension.  Mr. Belt believes ('The Naturalist in
Nicaragua,' p. 197) that the principal use of the beak is as a defence
against enemies, especially to the female whilst nesting in a hole in a
tree.)  The naked skin, also, at the base of the beak and round the eyes is
likewise often brilliantly coloured; and Mr. Gould, in speaking of one
species (52.  Rhamphastos carinatus, Gould's 'Monograph of Ramphastidae.'),
says that the colours of the beak "are doubtless in the finest and most
brilliant state during the time of pairing."  There is no greater
improbability that toucans should be encumbered with immense beaks, though
rendered as light as possible by their cancellated structure, for the
display of fine colours (an object falsely appearing to us unimportant),
than that the male Argus pheasant and some other birds should be encumbered
with plumes so long as to impede their flight.

In the same manner, as the males alone of various species are black, the
females being dull-coloured; so in a few cases the males alone are either
wholly or partially white, as with the several bell-birds of South America
(Chasmorhynchus), the Antarctic goose (Bernicla antarctica), the silver
pheasant, etc., whilst the females are brown or obscurely mottled.
Therefore, on the same principle as before, it is probable that both sexes
of many birds, such as white cockatoos, several egrets with their beautiful
plumes, certain ibises, gulls, terns, etc., have acquired their more or
less completely white plumage through sexual selection.  In some of these
cases the plumage becomes white only at maturity.  This is the case with
certain gannets, tropic-birds, etc., and with the snow-goose (Anser
hyperboreus).  As the latter breeds on the "barren grounds," when not
covered with snow, and as it migrates southward during the winter, there is
no reason to suppose that its snow-white adult plumage serves as a
protection.  In the Anastomus oscitans, we have still better evidence that
the white plumage is a nuptial character, for it is developed only during the
summer; the young in their immature state, and the adults in their winter
dress, being grey and black.  With many kinds of gulls (Larus), the head
and neck become pure white during the summer, being grey or mottled during
the winter and in the young state.  On the other hand, with the smaller
gulls, or sea-mews (Gavia), and with some terns (Sterna), exactly the
reverse occurs; for the heads of the young birds during the first year, and
of the adults during the winter, are either pure white, or much paler
coloured than during the breeding-season.  These latter cases offer another
instance of the capricious manner in which sexual selection appears often
to have acted.  (53.  On Larus, Gavia, and Sterna, see Macgillivray,
'History of British Birds,' vol. v. pp. 515, 584, 626.  On the Anser
hyperboreus, Audubon, 'Ornithological Biography,' vol. iv. p. 562.  On the
Anastomus, Mr. Blyth, in 'Ibis,' 1867, p. 173.)

That aquatic birds have acquired a white plumage so much oftener than
terrestrial birds, probably depends on their large size and strong powers
of flight, so that they can easily defend themselves or escape from birds
of prey, to which moreover they are not much exposed.  Consequently, sexual
selection has not here been interfered with or guided for the sake of
protection.  No doubt with birds which roam over the open ocean, the males
and females could find each other much more easily, when made conspicuous
either by being perfectly white or intensely black; so that these colours
may possibly serve the same end as the call-notes of many land-birds.  (54.
It may be noticed that with vultures, which roam far and wide high in the
air, like marine birds over the ocean, three or four species are almost
wholly or largely white, and that many others are black.  So that here
again conspicuous colours may possibly aid the sexes in finding each other
during the breeding-season.)  A white or black bird when it discovers and
flies down to a carcase floating on the sea or cast up on the beach, will
be seen from a great distance, and will guide other birds of the same and
other species, to the prey; but as this would be a disadvantage to the
first finders, the individuals which were the whitest or blackest would not
thus procure more food than the less strongly coloured individuals.  Hence
conspicuous colours cannot have been gradually acquired for this purpose
through natural selection.

As sexual selection depends on so fluctuating an element as taste, we can
understand how it is that, within the same group of birds having nearly the
same habits, there should exist white or nearly white, as well as black, or
nearly black species,--for instance, both white and black cockatoos,
storks, ibises, swans, terns, and petrels.  Piebald birds likewise
sometimes occur in the same groups together with black and white species;
for instance, the black-necked swan, certain terns, and the common magpie.
That a strong contrast in colour is agreeable to birds, we may conclude by
looking through any large collection, for the sexes often differ from each
other in the male having the pale parts of a purer white, and the variously
coloured dark parts of still darker tints than the female.

It would even appear that mere novelty, or slight changes for the sake of
change, have sometimes acted on female birds as a charm, like changes of
fashion with us.  Thus the males of some parrots can hardly be said to be
more beautiful than the females, at least according to our taste, but they
differ in such points, as in having a rose-coloured collar instead of "a
bright emeraldine narrow green collar"; or in the male having a black
collar instead of "a yellow demi-collar in front," with a pale roseate
instead of a plum-blue head.  (55.  See Jerdon on the genus Palaeornis,
'Birds of India,' vol. i. pp. 258-260.)  As so many male birds have
elongated tail-feathers or elongated crests for their chief ornament, the
shortened tail, formerly described in the male of a humming-bird, and the
shortened crest of the male goosander, seem like one of the many changes of
fashion which we admire in our own dresses.

Some members of the heron family offer a still more curious case of novelty
in colouring having, as it appears, been appreciated for the sake of
novelty.  The young of the Ardea asha are white, the adults being dark
slate-coloured; and not only the young, but the adults in their winter
plumage, of the allied Buphus coromandus are white, this colour changing
into a rich golden-buff during the breeding-season.  It is incredible that
the young of these two species, as well as of some other members of the
same family (56.  The young of Ardea rufescens and A. caerulea of the
United States are likewise white, the adults being coloured in accordance
with their specific names.  Audubon ('Ornithological Biography,' vol. iii.
p. 416; vol. iv. p. 58) seems rather pleased at the thought that this
remarkable change of plumage will greatly "disconcert the systematists."),
should for any special purpose have been rendered pure white and thus made
conspicuous to their enemies; or that the adults of one of these two
species should have been specially rendered white during the winter in a
country which is never covered with snow.  On the other hand we have good
reason to believe that whiteness has been gained by many birds as a sexual
ornament.  We may therefore conclude that some early progenitor of the
Ardea asha and the Buphus acquired a white plumage for nuptial purposes,
and transmitted this colour to their young; so that the young and the old
became white like certain existing egrets; and that the whiteness was
afterwards retained by the young, whilst it was exchanged by the adults for
more strongly-pronounced tints.  But if we could look still further back to
the still earlier progenitors of these two species, we should probably see
the adults dark-coloured.  I infer that this would be the case, from the
analogy of many other birds, which are dark whilst young, and when adult
are white; and more especially from the case of the Ardea gularis, the
colours of which are the reverse of those of A. asha, for the young are
dark-coloured and the adults white, the young having retained a former
state of plumage.  It appears therefore that, during a long line of
descent, the adult progenitors of the Ardea asha, the Buphus, and of some
allies, have undergone the following changes of colour:  first, a dark
shade; secondly, pure white; and thirdly, owing to another change of
fashion (if I may so express myself), their present slaty, reddish, or
golden-buff tints.  These successive changes are intelligible only on the
principle of novelty having been admired by birds for its own sake.

Several writers have objected to the whole theory of sexual selection, by
assuming that with animals and savages the taste of the female for certain
colours or other ornaments would not remain constant for many generations;
that first one colour and then another would be admired, and consequently
that no permanent effect could be produced.  We may admit that taste is
fluctuating, but it is not quite arbitrary.  It depends much on habit, as
we see in mankind; and we may infer that this would hold good with birds
and other animals.  Even in our own dress, the general character lasts
long, and the changes are to a certain extent graduated.  Abundant evidence
will be given in two places in a future chapter, that savages of many races
have admired for many generations the same cicatrices on the skin, the same
hideously perforated lips, nostrils, or ears, distorted heads, etc.; and
these deformities present some analogy to the natural ornaments of various
animals.  Nevertheless, with savages such fashions do not endure for ever,
as we may infer from the differences in this respect between allied tribes
on the same continent.  So again the raisers of fancy animals certainly
have admired for many generations and still admire the same breeds; they
earnestly desire slight changes, which are considered as improvements, but
any great or sudden change is looked at as the greatest blemish.  With
birds in a state of nature we have no reason to suppose that they would
admire an entirely new style of coloration, even if great and sudden
variations often occurred, which is far from being the case.  We know that
dovecot pigeons do not willingly associate with the variously coloured
fancy breeds; that albino birds do not commonly get partners in marriage;
and that the black ravens of the Feroe Islands chase away their piebald
brethren.  But this dislike of a sudden change would not preclude their
appreciating slight changes, any more than it does in the case of man.
Hence with respect to taste, which depends on many elements, but partly on
habit and partly on a love of novelty, there seems no improbability in
animals admiring for a very long period the same general style of
ornamentation or other attractions, and yet appreciating slight changes in
colours, form, or sound.

SUMMARY OF THE FOUR CHAPTERS ON BIRDS.

Most male birds are highly pugnacious during the breeding-season, and some
possess weapons adapted for fighting with their rivals.  But the most
pugnacious and the best armed males rarely or never depend for success
solely on their power to drive away or kill their rivals, but have special
means for charming the female.  With some it is the power of song, or of
giving forth strange cries, or instrumental music, and the males in
consequence differ from the females in their vocal organs, or in the
structure of certain feathers.  From the curiously diversified means for
producing various sounds, we gain a high idea of the importance of this
means of courtship.  Many birds endeavour to charm the females by love-
dances or antics, performed on the ground or in the air, and sometimes at
prepared places.  But ornaments of many kinds, the most brilliant tints,
combs and wattles, beautiful plumes, elongated feathers, top-knots, and so
forth, are by far the commonest means.  In some cases mere novelty appears
to have acted as a charm.  The ornaments of the males must be highly
important to them, for they have been acquired in not a few cases at the
cost of increased danger from enemies, and even at some loss of power in
fighting with their rivals.  The males of very many species do not assume
their ornamental dress until they arrive at maturity, or they assume it
only during the breeding-season, or the tints then become more vivid.
Certain ornamental appendages become enlarged, turgid, and brightly
coloured during the act of courtship.  The males display their charms with
elaborate care and to the best effect; and this is done in the presence of
the females.  The courtship is sometimes a prolonged affair, and many males
and females congregate at an appointed place.  To suppose that the females
do not appreciate the beauty of the males, is to admit that their splendid
decorations, all their pomp and display, are useless; and this is
incredible.  Birds have fine powers of discrimination, and in some few
instances it can be shewn that they have a taste for the beautiful.  The
females, moreover, are known occasionally to exhibit a marked preference or
antipathy for certain individual males.

If it be admitted that the females prefer, or are unconsciously excited by
the more beautiful males, then the males would slowly but surely be
rendered more and more attractive through sexual selection.  That it is
this sex which has been chiefly modified, we may infer from the fact that,
in almost every genus where the sexes differ, the males differ much more
from one another than do the females; this is well shewn in certain
closely-allied representative species, in which the females can hardly be
distinguished, whilst the males are quite distinct.  Birds in a state of
nature offer individual differences which would amply suffice for the work
of sexual selection; but we have seen that they occasionally present more
strongly marked variations which recur so frequently that they would
immediately be fixed, if they served to allure the female.  The laws of
variation must determine the nature of the initial changes, and will have
largely influenced the final result.  The gradations, which may be observed
between the males of allied species, indicate the nature of the steps
through which they have passed.  They explain also in the most interesting
manner how certain characters have originated, such as the indented ocelli
on the tail-feathers of the peacock, and the ball-and-socket ocelli on the
wing-feathers of the Argus pheasant.  It is evident that the brilliant
colours, top-knots, fine plumes, etc., of many male birds cannot have been
acquired as a protection; indeed, they sometimes lead to danger.  That they
are not due to the direct and definite action of the conditions of life, we
may feel assured, because the females have been exposed to the same
conditions, and yet often differ from the males to an extreme degree.
Although it is probable that changed conditions acting during a lengthened
period have in some cases produced a definite effect on both sexes, or
sometimes on one sex alone, the more important result will have been an
increased tendency to vary or to present more strongly-marked individual
differences; and such differences will have afforded an excellent ground-
work for the action of sexual selection.

The laws of inheritance, irrespectively of selection, appear to have
determined whether the characters acquired by the males for the sake of
ornament, for producing various sounds, and for fighting together, have
been transmitted to the males alone or to both sexes, either permanently,
or periodically during certain seasons of the year.  Why various characters
should have been transmitted sometimes in one way and sometimes in another,
is not in most cases known; but the period of variability seems often to
have been the determining cause.  When the two sexes have inherited all
characters in common they necessarily resemble each other; but as the
successive variations may be differently transmitted, every possible
gradation may be found, even within the same genus, from the closest
similarity to the widest dissimilarity between the sexes.  With many
closely-allied species, following nearly the same habits of life, the males
have come to differ from each other chiefly through the action of sexual
selection; whilst the females have come to differ chiefly from partaking
more or less of the characters thus acquired by the males.  The effects,
moreover, of the definite action of the conditions of life, will not have
been masked in the females, as in the males, by the accumulation through
sexual selection of strongly-pronounced colours and other ornaments.  The
individuals of both sexes, however affected, will have been kept at each
successive period nearly uniform by the free intercrossing of many
individuals.

With species, in which the sexes differ in colour, it is possible or
probable that some of the successive variations often tended to be
transmitted equally to both sexes; but that when this occurred the females
were prevented from acquiring the bright colours of the males, by the
destruction which they suffered during incubation.  There is no evidence
that it is possible by natural selection to convert one form of
transmission into another.  But there would not be the least difficulty in
rendering a female dull-coloured, the male being still kept bright-
coloured, by the selection of successive variations, which were from the
first limited in their transmission to the same sex.  Whether the females
of many species have actually been thus modified, must at present remain
doubtful.  When, through the law of the equal transmission of characters to
both sexes, the females were rendered as conspicuously coloured as the
males, their instincts appear often to have been modified so that they were
led to build domed or concealed nests.

In one small and curious class of cases the characters and habits of the
two sexes have been completely transposed, for the females are larger,
stronger, more vociferous and brighter coloured than the males.  They have,
also, become so quarrelsome that they often fight together for the
possession of the males, like the males of other pugnacious species for the
possession of the females.  If, as seems probable, such females habitually
drive away their rivals, and by the display of their bright colours or
other charms endeavour to attract the males, we can understand how it is
that they have gradually been rendered, by sexual selection and sexually-
limited transmission, more beautiful than the males--the latter being left
unmodified or only slightly modified.

Whenever the law of inheritance at corresponding ages prevails but not that
of sexually-limited transmission, then if the parents vary late in life--
and we know that this constantly occurs with our poultry, and occasionally
with other birds--the young will be left unaffected, whilst the adults of
both sexes will be modified.  If both these laws of inheritance prevail and
either sex varies late in life, that sex alone will be modified, the other
sex and the young being unaffected.  When variations in brightness or in
other conspicuous characters occur early in life, as no doubt often
happens, they will not be acted on through sexual selection until the
period of reproduction arrives; consequently if dangerous to the young,
they will be eliminated through natural selection.  Thus we can understand
how it is that variations arising late in life have so often been preserved
for the ornamentation of the males; the females and the young being left
almost unaffected, and therefore like each other.  With species having a
distinct summer and winter plumage, the males of which either resemble or
differ from the females during both seasons or during the summer alone, the
degrees and kinds of resemblance between the young and the old are
exceedingly complex; and this complexity apparently depends on characters,
first acquired by the males, being transmitted in various ways and degrees,
as limited by age, sex, and season.

As the young of so many species have been but little modified in colour and
in other ornaments, we are enabled to form some judgment with respect to
the plumage of their early progenitors; and we may infer that the beauty of
our existing species, if we look to the whole class, has been largely
increased since that period, of which the immature plumage gives us an
indirect record.  Many birds, especially those which live much on the
ground, have undoubtedly been obscurely coloured for the sake of
protection.  In some instances the upper exposed surface of the plumage has
been thus coloured in both sexes, whilst the lower surface in the males
alone has been variously ornamented through sexual selection.  Finally,
from the facts given in these four chapters, we may conclude that weapons
for battle, organs for producing sound, ornaments of many kinds, bright and
conspicuous colours, have generally been acquired by the males through
variation and sexual selection, and have been transmitted in various ways
according to the several laws of inheritance--the females and the young
being left comparatively but little modified.  (57.  I am greatly indebted
to the kindness of Mr. Sclater for having looked over these four chapters
on birds, and the two following ones on mammals.  In this way I have been
saved from making mistakes about the names of the species, and from stating
anything as a fact which is known to this distinguished naturalist to be
erroneous.  But, of course, he is not at all answerable for the accuracy of
the statements quoted by me from various authorities.)


CHAPTER XVII.

SECONDARY SEXUAL CHARACTERS OF MAMMALS.

The law of battle--Special weapons, confined to the males--Cause of absence
of weapons in the female--Weapons common to both sexes, yet primarily
acquired by the male--Other uses of such weapons--Their high importance--
Greater size of the male--Means of defence--On the preference shown by
either sex in the pairing of quadrupeds.

With mammals the male appears to win the female much more through the law
of battle than through the display of his charms.  The most timid animals,
not provided with any special weapons for fighting, engage in desperate
conflicts during the season of love.  Two male hares have been seen to
fight together until one was killed; male moles often fight, and sometimes
with fatal results; male squirrels engage in frequent contests, "and often
wound each other severely"; as do male beavers, so that "hardly a skin is
without scars."  (1.  See Waterton's account of two hares fighting,
'Zoologist,' vol. i. 1843, p. 211.  On moles, Bell, 'Hist. of British
Quadrupeds,' 1st ed., p. 100.  On squirrels, Audubon and Bachman,
Viviparous Quadrupeds of N. America, 1846, p. 269.  On beavers, Mr. A.H.
Green, in 'Journal of Linnean Society, Zoology,' vol. x. 1869, p. 362.)  I
observed the same fact with the hides of the guanacoes in Patagonia; and on
one occasion several were so absorbed in fighting that they fearlessly
rushed close by me.  Livingstone speaks of the males of the many animals in
Southern Africa as almost invariably shewing the scars received in former
contests.

The law of battle prevails with aquatic as with terrestrial mammals.  It is
notorious how desperately male seals fight, both with their teeth and
claws, during the breeding-season; and their hides are likewise often
covered with scars.  Male sperm-whales are very jealous at this season; and
in their battles "they often lock their jaws together, and turn on their
sides and twist about"; so that their lower jaws often become distorted.
(2.  On the battles of seals, see Capt. C. Abbott in 'Proc. Zool. Soc.'
1868, p. 191; Mr. R. Brown, ibid. 1868, p. 436; also L. Lloyd, 'Game Birds
of Sweden,' 1867, p. 412; also Pennant.  On the sperm-whale see Mr. J.H.
Thompson, in 'Proc. Zool. Soc.' 1867, p. 246.)

All male animals which are furnished with special weapons for fighting, are
well known to engage in fierce battles.  The courage and the desperate
conflicts of stags have often been described; their skeletons have been
found in various parts of the world, with the horns inextricably locked
together, shewing how miserably the victor and vanquished had perished.
(3.  See Scrope ('Art of Deer-stalking,' p. 17) on the locking of the horns
with the Cervus elaphus.  Richardson, in 'Fauna Bor. Americana,' 1829, p.
252, says that the wapiti, moose, and reindeer have been found thus locked
together.  Sir A. Smith found at the Cape of Good Hope the skeletons of
two gnus in the same condition.)  No animal in the world is so dangerous as
an elephant in must.  Lord Tankerville has given me a graphic description
of the battles between the wild bulls in Chillingham Park, the descendants,
degenerated in size but not in courage, of the gigantic Bos primigenius.
In 1861 several contended for mastery; and it was observed that two of the
younger bulls attacked in concert the old leader of the herd, overthrew and
disabled him, so that he was believed by the keepers to be lying mortally
wounded in a neighbouring wood.  But a few days afterwards one of the young
bulls approached the wood alone; and then the "monarch of the chase," who
had been lashing himself up for vengeance, came out and, in a short time,
killed his antagonist.  He then quietly joined the herd, and long held
undisputed sway.  Admiral Sir B.J. Sulivan informs me that, when he lived
in the Falkland Islands, he imported a young English stallion, which
frequented the hills near Port William with eight mares.  On these hills
there were two wild stallions, each with a small troop of mares; "and it is
certain that these stallions would never have approached each other without
fighting.  Both had tried singly to fight the English horse and drive away
his mares, but had failed.  One day they came in TOGETHER and attacked him.
This was seen by the capitan who had charge of the horses, and who, on
riding to the spot, found one of the two stallions engaged with the English
horse, whilst the other was driving away the mares, and had already
separated four from the rest.  The capitan settled the matter by driving
the whole party into the corral, for the wild stallions would not leave the
mares."

Male animals which are provided with efficient cutting or tearing teeth for
the ordinary purposes of life, such as the carnivora, insectivora, and
rodents, are seldom furnished with weapons especially adapted for fighting
with their rivals.  The case is very different with the males of many other
animals.  We see this in the horns of stags and of certain kinds of
antelopes in which the females are hornless.  With many animals the canine
teeth in the upper or lower jaw, or in both, are much larger in the males
than in the females, or are absent in the latter, with the exception
sometimes of a hidden rudiment.  Certain antelopes, the musk-deer, camel,
horse, boar, various apes, seals, and the walrus, offer instances.  In the
females of the walrus the tusks are sometimes quite absent.  (4.  Mr.
Lamont ('Seasons with the Sea-Horses,' 1861, p. 143) says that a good tusk
of the male walrus weighs 4 pounds, and is longer than that of the female,
which weighs about 3 pounds.  The males are described as fighting
ferociously.  On the occasional absence of the tusks in the female, see Mr.
R. Brown, 'Proceedings, Zoological Society,' 1868, p. 429.)  In the male
elephant of India and in the male dugong (5.  Owen, 'Anatomy of
Vertebrates,' vol. iii. p. 283.) the upper incisors form offensive weapons.
In the male narwhal the left canine alone is developed into the well-known,
spirally-twisted, so-called horn, which is sometimes from nine to ten feet
in length.  It is believed that the males use these horns for fighting
together; for "an unbroken one can rarely be got, and occasionally one may
be found with the point of another jammed into the broken place."  (6.  Mr.
R. Brown, in 'Proc. Zool. Soc.' 1869, p. 553.  See Prof. Turner, in
'Journal of Anat. and Phys.' 1872, p. 76, on the homological nature of
these tusks.  Also Mr. J.W. Clarke on two tusks being developed in the
males, in 'Proceedings of the Zoological Society,' 1871, p. 42.)  The tooth
on the opposite side of the head in the male consists of a rudiment about
ten inches in length, which is embedded in the jaw; but sometimes, though
rarely, both are equally developed on the two sides.  In the female both
are always rudimentary.  The male cachalot has a larger head than that of
the female, and it no doubt aids him in his aquatic battles.  Lastly, the
adult male ornithorhynchus is provided with a remarkable apparatus, namely
a spur on the foreleg, closely resembling the poison-fang of a venomous
snake; but according to Harting, the secretion from the gland is not
poisonous; and on the leg of the female there is a hollow, apparently for
the reception of the spur.  (7.  Owen on the cachalot and Ornithorhynchus,
ibid. vol. iii. pp. 638, 641.  Harting is quoted by Dr. Zouteveen in the
Dutch translation of this work, vol. ii. p. 292.)

When the males are provided with weapons which in the females are absent,
there can be hardly a doubt that these serve for fighting with other males;
and that they were acquired through sexual selection, and were transmitted
to the male sex alone.  It is not probable, at least in most cases, that
the females have been prevented from acquiring such weapons, on account of
their being useless, superfluous, or in some way injurious.  On the
contrary, as they are often used by the males for various purposes, more
especially as a defence against their enemies, it is a surprising fact that
they are so poorly developed, or quite absent, in the females of so many
animals.  With female deer the development during each recurrent season of
great branching horns, and with female elephants the development of immense
tusks, would be a great waste of vital power, supposing that they were of
no use to the females.  Consequently, they would have tended to be
eliminated in the female through natural selection; that is, if the
successive variations were limited in their transmission to the female sex,
for otherwise the weapons of the males would have been injuriously
affected, and this would have been a greater evil.  On the whole, and from
the consideration of the following facts, it seems probable that when the
various weapons differ in the two sexes, this has generally depended on the
kind of transmission which has prevailed.

As the reindeer is the one species in the whole family of Deer, in which
the female is furnished with horns, though they are somewhat smaller,
thinner, and less branched than in the male, it might naturally be thought
that, at least in this case, they must be of some special service to her.
The female retains her horns from the time when they are fully developed,
namely, in September, throughout the winter until April or May, when she
brings forth her young.  Mr. Crotch made particular enquiries for me in
Norway, and it appears that the females at this season conceal themselves
for about a fortnight in order to bring forth their young, and then
reappear, generally hornless.  In Nova Scotia, however, as I hear from Mr.
H. Reeks, the female sometimes retains her horns longer.  The male on the
other hand casts his horns much earlier, towards the end of November.  As
both sexes have the same requirements and follow the same habits of life,
and as the male is destitute of horns during the winter, it is improbable
that they can be of any special service to the female during this season,
which includes the larger part of the time during which she is horned.  Nor
is it probable that she can have inherited horns from some ancient
progenitor of the family of deer, for, from the fact of the females of so
many species in all quarters of the globe not having horns, we may conclude
that this was the primordial character of the group.  (8.  On the structure
and shedding of the horns of the reindeer, Hoffberg, 'Amoenitates Acad.'
vol. iv. 1788, p. 149.  See Richardson, 'Fauna Bor. Americana,' p. 241, in
regard to the American variety or species:  also Major W. Ross King, 'The
Sportsman in Canada,' 1866, p. 80.

The horns of the reindeer are developed at a most unusually early age; but
what the cause of this may be is not known.  The effect has apparently been
the transference of the horns to both sexes.  We should bear in mind that
horns are always transmitted through the female, and that she has a latent
capacity for their development, as we see in old or diseased females.  (9.
Isidore Geoffroy St.-Hilaire, 'Essais de Zoolog. Generale,' 1841, p. 513.
Other masculine characters, besides the horns, are sometimes similarly
transferred to the female; thus Mr. Boner, in speaking of an old female
chamois ('Chamois Hunting in the Mountains of Bavaria,' 1860, 2nd ed., p.
363), says, "not only was the head very male-looking, but along the back
there was a ridge of long hair, usually to be found only in bucks.")
Moreover the females of some other species of deer exhibit, either normally
or occasionally, rudiments of horns; thus the female of Cervulus moschatus
has "bristly tufts, ending in a knob, instead of a horn"; and "in most
specimens of the female wapiti (Cervus canadensis) there is a sharp bony
protuberance in the place of the horn."  (10.  On the Cervulus, Dr. Gray,
'Catalogue of Mammalia in the British Museum,' part iii. p. 220.  On the
Cervus canadensis or wapiti, see Hon. J.D. Caton, 'Ottawa Academy of Nat.
Sciences,' May 1868, p. 9.)  From these several considerations we may
conclude that the possession of fairly well-developed horns by the female
reindeer, is due to the males having first acquired them as weapons for
fighting with other males; and secondarily to their development from some
unknown cause at an unusually early age in the males, and their consequent
transference to both sexes.

Turning to the sheath-horned ruminants:  with antelopes a graduated series
can be formed, beginning with species, the females of which are completely
destitute of horns--passing on to those which have horns so small as to be
almost rudimentary (as with the Antilocapra americana, in which species
they are present in only one out of four or five females (11.  I am
indebted to Dr. Canfield for this information; see also his paper in the
'Proceedings of the Zoological Society,' 1866, p. 105.))--to those which
have fairly developed horns, but manifestly smaller and thinner than in the
male and sometimes of a different shape (12.  For instance the horns of the
female Ant. euchore resemble those of a distinct species, viz. the Ant.
dorcas var. Corine, see Desmarest, 'Mammalogie,' p. 455.),--and ending with
those in which both sexes have horns of equal size.  As with the reindeer,
so with antelopes, there exists, as previously shewn, a relation between
the period of the development of the horns and their transmission to one or
both sexes; it is therefore probable that their presence or absence in the
females of some species, and their more or less perfect condition in the
females of other species, depends, not on their being of any special use,
but simply on inheritance.  It accords with this view that even in the same
restricted genus both sexes of some species, and the males alone of others,
are thus provided.  It is also a remarkable fact that, although the females
of Antilope bezoartica are normally destitute of horns, Mr. Blyth has seen
no less than three females thus furnished; and there was no reason to
suppose that they were old or diseased.

In all the wild species of goats and sheep the horns are larger in the male
than in the female, and are sometimes quite absent in the latter.  (13.
Gray, 'Catalogue of Mammalia, the British Museum,' part iii. 1852, p. 160.)
In several domestic breeds of these two animals, the males alone are
furnished with horns; and in some breeds, for instance, in the sheep of
North Wales, though both sexes are properly horned, the ewes are very
liable to be hornless.  I have been informed by a trustworthy witness, who
purposely inspected a flock of these same sheep during the lambing season,
that the horns at birth are generally more fully developed in the male than
in the female.  Mr. J. Peel crossed his Lonk sheep, both sexes of which
always bear horns, with hornless Leicesters and hornless Shropshire Downs;
and the result was that the male offspring had their horns considerably
reduced, whilst the females were wholly destitute of them.  These several
facts indicate that, with sheep, the horns are a much less firmly fixed
character in the females than in the males; and this leads us to look at
the horns as properly of masculine origin.

With the adult musk-ox (Ovibos moschatus) the horns of the male are larger
than those of the female, and in the latter the bases do not touch.  (14.
Richardson, 'Fauna Bor. Americana,' p. 278.)  In regard to ordinary cattle
Mr. Blyth remarks:  "In most of the wild bovine animals the horns are both
longer and thicker in the bull than in the cow, and in the cow-banteng (Bos
sondaicus) the horns are remarkably small, and inclined much backwards.  In
the domestic races of cattle, both of the humped and humpless types, the
horns are short and thick in the bull, longer and more slender in the cow
and ox; and in the Indian buffalo, they are shorter and thicker in the
bull, longer and more slender in the cow.  In the wild gaour (B. gaurus)
the horns are mostly both longer and thicker in the bull than in the cow."
(15.  'Land and Water,' 1867, p. 346.)  Dr. Forsyth Major also informs me
that a fossil skull, believed to be that of the female Bos etruscus, has
been found in Val d'Arno, which is wholly without horns.  In the Rhinoceros
simus, as I may add, the horns of the female are generally longer but less
powerful than in the male; and in some other species of rhinoceros they are
said to be shorter in the female.  (16.  Sir Andrew Smith, 'Zoology of S.
Africa,' pl. xix. Owen, 'Anatomy of Vertebrates,' vol. iii. p. 624.)  From
these various facts we may infer as probable that horns of all kinds, even
when they are equally developed in the two sexes, were primarily acquired
by the male in order to conquer other males, and have been transferred more
or less completely to the female.

The effects of castration deserve notice, as throwing light on this same
point.  Stags after the operation never renew their horns.  The male
reindeer, however, must be excepted, as after castration he does renew
them.  This fact, as well as the possession of horns by both sexes, seems
at first to prove that the horns in this species do not constitute a sexual
character (17.  This is the conclusion of Seidlitz, 'Die Darwinsche
Theorie,' 1871, p. 47.); but as they are developed at a very early age,
before the sexes differ in constitution, it is not surprising that they
should be unaffected by castration, even if they were aboriginally acquired
by the male.  With sheep both sexes properly bear horns; and I am informed
that with Welch sheep the horns of the males are considerably reduced by
castration; but the degree depends much on the age at which the operation
is performed, as is likewise the case with other animals.  Merino rams have
large horns, whilst the ewes "generally speaking are without horns"; and in
this breed castration seems to produce a somewhat greater effect, so that
if performed at an early age the horns "remain almost undeveloped."  (18.
I am much obliged to Prof. Victor Carus, for having made enquiries for me
in Saxony on this subject.  H. von Nathusius ('Viehzucht,' 1872, p. 64)
says that the horns of sheep castrated at an early period, either
altogether disappear or remain as mere rudiments; but I do not know whether
he refers to merinos or to ordinary breeds.)  On the Guinea coast there is
a breed in which the females never bear horns, and, as Mr. Winwood Reade
informs me, the rams after castration are quite destitute of them.  With
cattle, the horns of the males are much altered by castration; for instead
of being short and thick, they become longer than those of the cow, but
otherwise resemble them.  The Antilope bezoartica offers a somewhat
analogous case:  the males have long straight spiral horns, nearly parallel
to each other, and directed backwards; the females occasionally bear horns,
but these when present are of a very different shape, for they are not
spiral, and spreading widely, bend round with the points forwards.  Now it

is a remarkable fact that, in the castrated male, as Mr. Blyth informs me,
the horns are of the same peculiar shape as in the female, but longer and
thicker.  If we may judge from analogy, the female probably shews us, in
these two cases of cattle and the antelope, the former condition of the
horns in some early progenitor of each species.  But why castration should
lead to the reappearance of an early condition of the horns cannot be
explained with any certainty.  Nevertheless, it seems probable, that in
nearly the same manner as the constitutional disturbance in the offspring,
caused by a cross between two distinct species or races, often leads to the
reappearance of long-lost characters (19.  I have given various experiments
and other evidence proving that this is the case, in my 'Variation of
Animals and Plants under Domestication,' vol. ii. 1868, pp. 39-47.); so
here, the disturbance in the constitution of the individual, resulting from
castration, produces the same effect.

The tusks of the elephant, in the different species or races, differ
according to sex, nearly as do the horns of ruminants.  In India and
Malacca the males alone are provided with well-developed tusks.  The
elephant of Ceylon is considered by most naturalists as a distinct race,
but by some as a distinct species, and here "not one in a hundred is found
with tusks, the few that possess them being exclusively males."  (20.  Sir
J. Emerson Tennent, 'Ceylon,' 1859, vol. ii. p. 274.  For Malacca, 'Journal
of Indian Archipelago,' vol. iv. p. 357.)  The African elephant is
undoubtedly distinct, and the female has large well-developed tusks, though
not so large as those of the male.

These differences in the tusks of the several races and species of
elephants--the great variability of the horns of deer, as notably in the
wild reindeer--the occasional presence of horns in the female Antilope
Bezoartica, and their frequent absence in the female of Antilocapra
americana--the presence of two tusks in some few male narwhals--the
complete absence of tusks in some female walruses--are all instances of the
extreme variability of secondary sexual characters, and of their liability
to differ in closely-allied forms.

Although tusks and horns appear in all cases to have been primarily
developed as sexual weapons, they often serve other purposes.  The elephant
uses his tusks in attacking the tiger; according to Bruce, he scores the
trunks of trees until they can be thrown down easily, and he likewise thus
extracts the farinaceous cores of palms; in Africa he often uses one tusk,
always the same, to probe the ground and thus ascertain whether it will
bear his weight.  The common bull defends the herd with his horns; and the
elk in Sweden has been known, according to Lloyd, to strike a wolf dead
with a single blow of his great horns.  Many similar facts could be given.
One of the most curious secondary uses to which the horns of an animal may
be occasionally put is that observed by Captain Hutton (21.  'Calcutta
Journal of Natural History,' vol. ii, 1843, p. 526.) with the wild goat
(Capra aegagrus) of the Himalayas and, as it is also said with the ibex,
namely that when the male accidentally falls from a height he bends inwards
his head, and by alighting on his massive horns, breaks the shock.  The
female cannot thus use her horns, which are smaller, but from her more
quiet disposition she does not need this strange kind of shield so much.

Each male animal uses his weapons in his own peculiar fashion.  The common
ram makes a charge and butts with such force with the bases of his horns,
that I have seen a powerful man knocked over like a child.  Goats and
certain species of sheep, for instance the Ovis cycloceros of Afghanistan
(22.  Mr. Blyth, in 'Land and Water,' March, 1867, p. 134, on the authority
of Capt. Hutton and others.  For the wild Pembrokeshire goats, see the
'Field,' 1869, p. 150.), rear on their hind legs, and then not only butt,
but "make a cut down and a jerk up, with the ribbed front of their
scimitar-shaped horn, as with a sabre.  When the O. cycloceros attacked a
large domestic ram, who was a noted bruiser, he conquered him by the sheer
novelty of his mode of fighting, always closing at once with his adversary,
and catching him across the face and nose with a sharp drawing jerk of the
head, and then bounding out of the way before the blow could be returned."
In Pembrokeshire a male goat, the master of a flock which during several
generations had run wild, was known to have killed several males in single
combat; this goat possessed enormous horns, measuring thirty-nine inches in
a straight line from tip to tip.  The common bull, as every one knows,
gores and tosses his opponent; but the Italian buffalo is said never to use
his horns:  he gives a tremendous blow with his convex forehead, and then
tramples on his fallen enemy with his knees--an instinct which the common
bull does not possess.  (23.  M. E.M. Bailly, "Sur l'usage des cornes,"
etc., .Annal des Sciences Nat.' tom. ii. 1824, p. 369.)  Hence a dog who
pins a buffalo by the nose is immediately crushed.  We must, however,
remember that the Italian buffalo has been long domesticated, and it is by
no means certain that the wild parent-form had similar horns.  Mr. Bartlett
informs me that when a female Cape buffalo (Bubalus caffer) was turned into
an enclosure with a bull of the same species, she attacked him, and he in
return pushed her about with great violence.  But it was manifest to Mr.
Bartlett that, had not the bull shewn dignified forbearance, he could
easily have killed her by a single lateral thrust with his immense horns.
The giraffe uses his short, hair-covered horns, which are rather longer in
the male than in the female, in a curious manner; for, with his long neck,
he swings his head to either side, almost upside down, with such force that
I have seen a hard plank deeply indented by a single blow.

[Fig. 63.  Oryx leucoryx, male (from the Knowsley Menagerie).]

With antelopes it is sometimes difficult to imagine how they can possibly
use their curiously-shaped horns; thus the springboc (Ant. euchore) has
rather short upright horns, with the sharp points bent inwards almost at
right angles, so as to face each other; Mr. Bartlett does not know how they
are used, but suggests that they would inflict a fearful wound down each
side of the face of an antagonist.  The slightly-curved horns of the Oryx
leucoryx (Fig. 63) are directed backwards, and are of such length that
their points reach beyond the middle of the back, over which they extend in
almost parallel lines.  Thus they seem singularly ill-fitted for fighting;
but Mr. Bartlett informs me that when two of these animals prepare for
battle, they kneel down, with their heads between their fore legs, and in
this attitude the horns stand nearly parallel and close to the ground, with
the points directed forwards and a little upwards.  The combatants then
gradually approach each other, and each endeavours to get the upturned
points under the body of the other; if one succeeds in doing this, he
suddenly springs up, throwing up his head at the same time, and can thus
wound or perhaps even transfix his antagonist.  Both animals always kneel
down, so as to guard as far as possible against this manoeuvre.  It has
been recorded that one of these antelopes has used his horn with effect
even against a lion; yet from being forced to place his head between the
forelegs in order to bring the points of the horns forward, he would
generally be under a great disadvantage when attacked by any other animal.
It is, therefore, not probable that the horns have been modified into their
present great length and peculiar position, as a protection against beasts
of prey.  We can however see that, as soon as some ancient male progenitor
of the Oryx acquired moderately long horns, directed a little backwards, he
would be compelled, in his battles with rival males, to bend his head
somewhat inwards or downwards, as is now done by certain stags; and it is
not improbable that he might have acquired the habit of at first
occasionally and afterwards of regularly kneeling down.  In this case it is
almost certain that the males which possessed the longest horns would have
had a great advantage over others with shorter horns; and then the horns
would gradually have been rendered longer and longer, through sexual
selection, until they acquired their present extraordinary length and
position.

With stags of many kinds the branches of the horns offer a curious case of
difficulty; for certainly a single straight point would inflict a much more
serious wound than several diverging ones.  In Sir Philip Egerton's museum
there is a horn of the red-deer (Cervus elaphus), thirty inches in length,
with "not fewer than fifteen snags or branches"; and at Moritzburg there is
still preserved a pair of antlers of a red-deer, shot in 1699 by Frederick
I., one of which bears the astonishing number of thirty-three branches and
the other twenty-seven, making altogether sixty branches.  Richardson
figures a pair of antlers of the wild reindeer with twenty-nine points.
(24.  On the horns of red-deer, Owen, 'British Fossil Mammals,' 1846, p.
478; Richardson on the horns of the reindeer, 'Fauna Bor. Americana,' 1829,
p. 240.  I am indebted to Prof. Victor Carus, for the Moritzburg case.)
From the manner in which the horns are branched, and more especially from
deer being known occasionally to fight together by kicking with their fore-
feet (25.  Hon. J.D. Caton ('Ottawa Acad. of Nat. Science,' May 1868, p. 9)
says that the American deer fight with their fore-feet, after "the question
of superiority has been once settled and acknowledged in the herd."
Bailly, 'Sur l'Usage des cornes,' 'Annales des Sciences Nat.' tom. ii.
1824, p. 371.), M. Bailly actually comes to the conclusion that their horns
are more injurious than useful to them.  But this author overlooks the
pitched battles between rival males.  As I felt much perplexed about the
use or advantage of the branches, I applied to Mr. McNeill of Colonsay, who
has long and carefully observed the habits of red-deer, and he informs me
that he has never seen some of the branches brought into use, but that the
brow antlers, from inclining downwards, are a great protection to the
forehead, and their points are likewise used in attack.  Sir Philip Egerton
also informs me both as to red-deer and fallow-deer that, in fighting, they
suddenly dash together, and getting their horns fixed against each other's
bodies, a desperate struggle ensues.  When one is at last forced to yield
and turn round, the victor endeavours to plunge his brow antlers into his
defeated foe.  It thus appears that the upper branches are used chiefly or
exclusively for pushing and fencing.  Nevertheless in some species the
upper branches are used as weapons of offence; when a man was attacked by a
wapiti deer (Cervus canadensis) in Judge Caton's park in Ottawa, and
several men tried to rescue him, the stag "never raised his head from the
ground; in fact he kept his face almost flat on the ground, with his nose
nearly between his fore feet, except when he rolled his head to one side to
take a new observation preparatory to a plunge."  In this position the ends
of the horns were directed against his adversaries.  "In rolling his head
he necessarily raised it somewhat, because his antlers were so long that he
could not roll his head without raising them on one side, while, on the
other side they touched the ground."  The stag by this procedure gradually
drove the party of rescuers backwards to a distance of 150 or 200 feet; and
the attacked man was killed.  (26.  See a most interesting account in the
Appendix to Hon. J.D. Caton's paper, as above quoted.)

[Fig. 64.  Strepsiceros Kudu (from Sir Andrew Smith's 'Zoology of South
Africa.']

Although the horns of stags are efficient weapons, there can, I think, be no
doubt that a single point would have been much more dangerous than a
branched antler; and Judge Caton, who has had large experience with deer,
fully concurs in this conclusion.  Nor do the branching horns, though
highly important as a means of defence against rival stags, appear
perfectly well adapted for this purpose, as they are liable to become
interlocked.  The suspicion has therefore crossed my mind that they may
serve in part as ornaments.  That the branched antlers of stags as well as
the elegant lyrated horns of certain antelopes, with their graceful double
curvature (Fig. 64), are ornamental in our eyes, no one will dispute.  If,
then, the horns, like the splendid accoutrements of the knights of old, add
to the noble appearance of stags and antelopes, they may have been modified
partly for this purpose, though mainly for actual service in battle; but I
have no evidence in favour of this belief.

An interesting case has lately been published, from which it appears that
the horns of a deer in one district in the United States are now being
modified through sexual and natural selection.  A writer in an excellent
American Journal (27.  The 'American Naturalist,' Dec. 1869, p. 552.) says,
that he has hunted for the last twenty-one years in the Adirondacks, where
the Cervus virginianus abounds.  About fourteen years ago he first heard of
SPIKE-HORN BUCKS.  These became from year to year more common; about five
years ago he shot one, and afterwards another, and now they are frequently
killed.  "The spike-horn differs greatly from the common antler of the C.
virginianus.  It consists of a single spike, more slender than the antler,
and scarcely half so long, projecting forward from the brow, and
terminating in a very sharp point.  It gives a considerable advantage to
its possessor over the common buck.  Besides enabling him to run more
swiftly through the thick woods and underbrush (every hunter knows that
does and yearling bucks run much more rapidly than the large bucks when
armed with their cumbrous antlers), the spike-horn is a more effective
weapon than the common antler.  With this advantage the spike-horn bucks
are gaining upon the common bucks, and may, in time, entirely supersede
them in the Adirondacks.  Undoubtedly, the first spike-horn buck was merely
an accidental freak of nature.  But his spike-horns gave him an advantage,
and enabled him to propagate his peculiarity.  His descendants having a
like advantage, have propagated the peculiarity in a constantly increasing
ratio, till they are slowly crowding the antlered deer from the region they
inhabit."  A critic has well objected to this account by asking, why, if
the simple horns are now so advantageous, were the branched antlers of the
parent-form ever developed?  To this I can only answer by remarking, that a
new mode of attack with new weapons might be a great advantage, as shewn by
the case of the Ovis cycloceros, who thus conquered a domestic ram famous
for his fighting power.  Though the branched antlers of a stag are well
adapted for fighting with his rivals, and though it might be an advantage
to the prong-horned variety slowly to acquire long and branched horns, if
he had to fight only with others of the same kind, yet it by no means
follows that branched horns would be the best fitted for conquering a foe
differently armed.  In the foregoing case of the Oryx leucoryx, it is
almost certain that the victory would rest with an antelope having short
horns, and who therefore did not need to kneel down, though an oryx might
profit by having still longer horns, if he fought only with his proper
rivals.

Male quadrupeds, which are furnished with tusks, use them in various ways,
as in the case of horns.  The boar strikes laterally and upwards; the musk-
deer downwards with serious effect.  (28.  Pallas, 'Spicilegia Zoologica,'
fasc. xiii. 1779, p. 18.)  The walrus, though having so short a neck and so
unwieldy a body, "can strike either upwards, or downwards, or sideways,
with equal dexterity."  (29.  Lamont, 'Seasons with the Sea-Horses,' 1861,
p. 141.)  I was informed by the late Dr. Falconer, that the Indian elephant
fights in a different manner according to the position and curvature of his
tusks.  When they are directed forwards and upwards he is able to fling a
tiger to a great distance--it is said to even thirty feet; when they are
short and turned downwards he endeavours suddenly to pin the tiger to the
ground and, in consequence, is dangerous to the rider, who is liable to be
jerked off the howdah.  (30.  See also Corse ('Philosophical Transactions,'
1799, p. 212) on the manner in which the short-tusked Mooknah variety
attacks other elephants.)

Very few male quadrupeds possess weapons of two distinct kinds specially
adapted for fighting with rival males.  The male muntjac-deer (Cervulus),
however, offers an exception, as he is provided with horns and exserted
canine teeth.  But we may infer from what follows that one form of weapon
has often been replaced in the course of ages by another.  With ruminants
the development of horns generally stands in an inverse relation with that
of even moderately developed canine teeth.  Thus camels, guanacoes,
chevrotains, and musk-deer, are hornless, and they have efficient canines;
these teeth being "always of smaller size in the females than in the
males."  The Camelidae have, in addition to their true canines, a pair of
canine-shaped incisors in their upper jaws.  (31.  Owen, 'Anatomy of
Vertebrates,' vol. iii. p. 349.)  Male deer and antelopes, on the other
hand, possess horns, and they rarely have canine teeth; and these, when
present, are always of small size, so that it is doubtful whether they are
of any service in their battles.  In Antilope montana they exist only as
rudiments in the young male, disappearing as he grows old; and they are
absent in the female at all ages; but the females of certain other
antelopes and of certain deer have been known occasionally to exhibit
rudiments of these teeth.  (32.  See Ruppell (in 'Proc. Zoolog. Soc.' Jan.
12, 1836, p. 3) on the canines in deer and antelopes, with a note by Mr.
Martin on a female American deer.  See also Falconer ('Palaeont. Memoirs
and Notes,' vol. i. 1868, p. 576) on canines in an adult female deer.  In
old males of the musk-deer the canines (Pallas, 'Spic. Zoolog.' fasc. xiii.
1779, p. 18) sometimes grow to the length of three inches, whilst in old
females a rudiment projects scarcely half an inch above the gums.)
Stallions have small canine teeth, which are either quite absent or
rudimentary in the mare; but they do not appear to be used in fighting, for
stallions bite with their incisors, and do not open their mouths wide like
camels and guanacoes.  Whenever the adult male possesses canines, now
inefficient, whilst the female has either none or mere rudiments, we may
conclude that the early male progenitor of the species was provided with
efficient canines, which have been partially transferred to the females.
The reduction of these teeth in the males seems to have followed from some
change in their manner of fighting, often (but not in the horse) caused by
the development of new weapons.

Tusks and horns are manifestly of high importance to their possessors, for
their development consumes much organised matter.  A single tusk of the
Asiatic elephant--one of the extinct woolly species--and of the African
elephant, have been known to weigh respectively 150, 160, and 180 pounds;
and even greater weights have been given by some authors.  (33.  Emerson
Tennent, 'Ceylon,' 1859, vol. ii. p. 275; Owen, 'British Fossil Mammals,'
1846, p. 245.)  With deer, in which the horns are periodically renewed, the
drain on the constitution must be greater; the horns, for instance, of the
moose weigh from fifty to sixty pounds, and those of the extinct Irish elk
from sixty to seventy pounds--the skull of the latter weighing on an
average only five pounds and a quarter.  Although the horns are not
periodically renewed in sheep, yet their development, in the opinion of
many agriculturists, entails a sensible loss to the breeder.  Stags,
moreover, in escaping from beasts of prey are loaded with an additional
weight for the race, and are greatly retarded in passing through a woody
country.  The moose, for instance, with horns extending five and a half
feet from tip to tip, although so skilful in their use that he will not
touch or break a twig when walking quietly, cannot act so dexterously
whilst rushing away from a pack of wolves.  "During his progress he holds
his nose up, so as to lay the horns horizontally back; and in this attitude
cannot see the ground distinctly."  (34.  Richardson, 'Fauna Bor.
Americana,' on the moose, Alces palmata, pp. 236, 237; on the expanse of
the horns, 'Land and Water,' 1869, p. 143.  See also Owen, 'British Fossil
Mammals,' on the Irish elk, pp. 447, 455.)  The tips of the horns of the
great Irish elk were actually eight feet apart!  Whilst the horns are
covered with velvet, which lasts with red-deer for about twelve weeks, they
are extremely sensitive to a blow; so that in Germany the stags at this
time somewhat change their habits, and avoiding dense forests, frequent
young woods and low thickets.  (35.  'Forest Creatures,' by C. Boner, 1861,
p. 60.)  These facts remind us that male birds have acquired ornamental
plumes at the cost of retarded flight, and other ornaments at the cost of
some loss of power in their battles with rival males.

With mammals, when, as is often the case, the sexes differ in size, the
males are almost always larger and stronger.  I am informed by Mr. Gould
that this holds good in a marked manner with the marsupials of Australia,
the males of which appear to continue growing until an unusually late age.
But the most extraordinary case is that of one of the seals (Callorhinus
ursinus), a full-grown female weighing less than one-sixth of a full-grown
male.  (36.  See the very interesting paper by Mr. J.A. Allen in 'Bull.
Mus. Comp. Zoology of Cambridge, United States,' vol. ii. No. 1, p. 82.
The weights were ascertained by a careful observer, Capt. Bryant.  Dr. Gill
in 'The American Naturalist,' January, 1871, Prof. Shaler on the relative
size of the sexes of whales, 'American Naturalist,' January, 1873.)  Dr.
Gill remarks that it is with the polygamous seals, the males of which are
well known to fight savagely together, that the sexes differ much in size;
the monogamous species differing but little.  Whales also afford evidence
of the relation existing between the pugnacity of the males and their large
size compared with that of the female; the males of the right-whales do not
fight together, and they are not larger, but rather smaller, than their
females; on the other hand, male sperm-whales fight much together, and
their bodies are "often found scarred with the imprint of their rival's
teeth," and they are double the size of the females.  The greater strength
of the male, as Hunter long ago remarked (37.  'Animal Economy,' p. 45.),
is invariably displayed in those parts of the body which are brought into
action in fighting with rival males--for instance, in the massive neck of
the bull.  Male quadrupeds are also more courageous and pugnacious than the
females.  There can be little doubt that these characters have been gained,
partly through sexual selection, owing to a long series of victories, by
the stronger and more courageous males over the weaker, and partly through
the inherited effects of use.  It is probable that the successive
variations in strength, size, and courage, whether due to mere variability
or to the effects of use, by the accumulation of which male quadrupeds have
acquired these characteristic qualities, occurred rather late in life, and
were consequently to a large extent limited in their transmission to the
same sex.

From these considerations I was anxious to obtain information as to the
Scotch deer-hound, the sexes of which differ more in size than those of any
other breed (though blood-hounds differ considerably), or than in any wild
canine species known to me.  Accordingly, I applied to Mr. Cupples, well
known for his success with this breed, who has weighed and measured many of
his own dogs, and who has with great kindness collected for me the
following facts from various sources.  Fine male dogs, measured at the
shoulder, range from 28 inches, which is low, to 33 or even 34 inches in
height; and in weight from 80 pounds, which is light, to 120 pounds, or
even more.  The females range in height from 23 to 27, or even to 28
inches; and in weight from 50 to 70, or even 80 pounds.  (38.  See also
Richardson's 'Manual on the Dog,' p. 59.  Much valuable information on the
Scottish deer-hound is given by Mr. McNeill, who first called attention to
the inequality in size between the sexes, in Scrope's 'Art of Deer-
Stalking.'  I hope that Mr. Cupples will keep to his intention of
publishing a full account and history of this famous breed.)  Mr. Cupples
concludes that from 95 to 100 pounds for the male, and 70 for the female,
would be a safe average; but there is reason to believe that formerly both
sexes attained a greater weight.  Mr. Cupples has weighed puppies when a
fortnight old; in one litter the average weight of four males exceeded that
of two females by six and a half ounces; in another litter the average
weight of four males exceeded that of one female by less than one ounce;
the same males when three weeks old, exceeded the female by seven and a
half ounces, and at the age of six weeks by nearly fourteen ounces.  Mr.
Wright of Yeldersley House, in a letter to Mr. Cupples, says:  "I have
taken notes on the sizes and weights of puppies of many litters, and as far
as my experience goes, dog-puppies as a rule differ very little from
bitches till they arrive at about five or six months old; and then the dogs
begin to increase, gaining upon the bitches both in weight and size.  At
birth, and for several weeks afterwards, a bitch-puppy will occasionally be
larger than any of the dogs, but they are invariably beaten by them later."
Mr. McNeill, of Colonsay, concludes that "the males do not attain their
full growth till over two years old, though the females attain it sooner."
According to Mr. Cupples' experience, male dogs go on growing in stature
till they are from twelve to eighteen months old, and in weight till from
eighteen to twenty-four months old; whilst the females cease increasing in
stature at the age of from nine to fourteen or fifteen months, and in
weight at the age of from twelve to fifteen months.  From these various
statements it is clear that the full difference in size between the male
and female Scotch deer-hound is not acquired until rather late in life.
The males almost exclusively are used for coursing, for, as Mr. McNeill
informs me, the females have not sufficient strength and weight to pull
down a full-grown deer.  From the names used in old legends, it appears, as
I hear from Mr. Cupples, that, at a very ancient period, the males were the
most celebrated, the females being mentioned only as the mothers of famous
dogs.  Hence, during many generations, it is the male which has been
chiefly tested for strength, size, speed, and courage, and the best will
have been bred from.  As, however, the males do not attain their full
dimensions until rather late in life, they will have tended, in accordance
with the law often indicated, to transmit their characters to their male
offspring alone; and thus the great inequality in size between the sexes of
the Scotch deer-hound may probably be accounted for.

[Fig. 65.  Head of Common wild boar, in prime of life (from Brehm).]

The males of some few quadrupeds possess organs or parts developed solely
as a means of defence against the attacks of other males.  Some kinds of
deer use, as we have seen, the upper branches of their horns chiefly or
exclusively for defending themselves; and the Oryx antelope, as I am
informed by Mr. Bartlett, fences most skilfully with his long, gently
curved horns; but these are likewise used as organs of offence.  The same
observer remarks that rhinoceroses in fighting, parry each other's sidelong
blows with their horns, which clatter loudly together, as do the tusks of
boars.  Although wild boars fight desperately, they seldom, according to
Brehm, receive fatal wounds, as the blows fall on each other's tusks, or on
the layer of gristly skin covering the shoulder, called by the German
hunters, the shield; and here we have a part specially modified for
defence.  With boars in the prime of life (Fig. 65) the tusks in the lower
jaw are used for fighting, but they become in old age, as Brehm states, so
much curved inwards and upwards over the snout that they can no longer be
used in this way.  They may, however, still serve, and even more
effectively, as a means of defence.  In compensation for the loss of the
lower tusks as weapons of offence, those in the upper jaw, which always
project a little laterally, increase in old age so much in length and curve
so much upwards that they can be used for attack.  Nevertheless, an old
boar is not so dangerous to man as one at the age of six or seven years.
(39.  Brehm, 'Thierleben,' B. ii. ss. 729-732.)

[Fig. 66.  Skull of the Babirusa Pig (from Wallace's 'Malay Archipelago').]

In the full-grown male Babirusa pig of Celebes (Fig. 66), the lower tusks
are formidable weapons, like those of the European boar in the prime of
life, whilst the upper tusks are so long and have their points so much
curled inwards, sometimes even touching the forehead, that they are utterly
useless as weapons of attack.  They more nearly resemble horns than teeth,
and are so manifestly useless as teeth that the animal was formerly
supposed to rest his head by hooking them on to a branch!  Their convex
surfaces, however, if the head were held a little laterally, would serve as
an excellent guard; and hence, perhaps, it is that in old animals they "are
generally broken off, as if by fighting."  (40.  See Mr. Wallace's
interesting account of this animal, 'The Malay Archipelago,' 1869, vol. i.
p. 435.)  Here, then, we have the curious case of the upper tusks of the
Babirusa regularly assuming during the prime of life a structure which
apparently renders them fitted only for defence; whilst in the European
boar the lower tusks assume in a less degree and only during old age nearly
the same form, and then serve in like manner solely for defence.

[Fig. 67.  Head of female Aethiopian wart-hog, from 'Proc. Zool. Soc.' 1869,
shewing the same characters as the male, though on a reduced scale.
N.B. When the engraving was first made, I was under the impression that it
represented the male.]

In the wart-hog (see Phacochoerus aethiopicus, Fig. 67) the tusks in the
upper jaw of the male curve upwards during the prime of life, and from
being pointed serve as formidable weapons.  The tusks in the lower jaw are
sharper than those in the upper, but from their shortness it seems hardly
possible that they can be used as weapons of attack.  They must, however,
greatly strengthen those in the upper jaw, from being ground so as to fit
closely against their bases.  Neither the upper nor the lower tusks appear
to have been specially modified to act as guards, though no doubt they are
to a certain extent used for this purpose.  But the wart-hog is not
destitute of other special means of protection, for it has, on each side of
the face, beneath the eyes, a rather stiff, yet flexible, cartilaginous,
oblong pad (Fig. 67), which projects two or three inches outwards; and it
appeared to Mr. Bartlett and myself, when viewing the living animal, that
these pads, when struck from beneath by the tusks of an opponent, would be
turned upwards, and would thus admirably protect the somewhat prominent
eyes.  I may add, on the authority of Mr. Bartlett, that these boars when
fighting stand directly face to face.

Lastly, the African river-hog (Potomochoerus penicillatus) has a hard
cartilaginous knob on each side of the face beneath the eyes, which answers
to the flexible pad of the wart-hog; it has also two bony prominences on
the upper jaw above the nostrils.  A boar of this species in the Zoological
Gardens recently broke into the cage of the wart-hog.  They fought all
night long, and were found in the morning much exhausted, but not seriously
wounded.  It is a significant fact, as shewing the purposes of the above-
described projections and excrescences, that these were covered with blood,
and were scored and abraded in an extraordinary manner.

Although the males of so many members of the pig family are provided with
weapons, and as we have just seen with means of defence, these weapons seem
to have been acquired within a rather late geological period.  Dr. Forsyth
Major specifies (41.  'Atti della Soc. Italiana di Sc. Nat.' 1873, vol. xv.
fasc. iv.) several miocene species, in none of which do the tusks appear to
have been largely developed in the males; and Professor Rutimeyer was
formerly struck with this same fact.

The mane of the lion forms a good defence against the attacks of rival
lions, the one danger to which he is liable; for the males, as Sir A. Smith
informs me, engage in terrible battles, and a young lion dares not approach
an old one.  In 1857 a tiger at Bromwich broke into the cage of a lion and
a fearful scene ensued:  "the lion's mane saved his neck and head from
being much injured, but the tiger at last succeeded in ripping up his
belly, and in a few minutes he was dead."  (42.  'The Times,' Nov. 10,
1857.  In regard to the Canada lynx, see Audubon and Bachman, 'Quadrupeds
of North America,' 1846, p. 139.)  The broad ruff round the throat and chin
of the Canadian lynx (Felis canadensis) is much longer in the male than in
the female; but whether it serves as a defence I do not know.  Male seals
are well known to fight desperately together, and the males of certain
kinds (Otaria jubata) (43.  Dr. Murie, on Otaria, 'Proc. Zoolog. Soc.'
1869, p. 109.  Mr. J.A. Allen, in the paper above quoted (p. 75), doubts
whether the hair, which is longer on the neck in the male than in the
female, deserves to be called a mane.) have great manes, whilst the females
have small ones or none.  The male baboon of the Cape of Good Hope
(Cynocephalus porcarius) has a much longer mane and larger canine teeth
than the female; and the mane probably serves as a protection, for, on
asking the keepers in the Zoological Gardens, without giving them any clue
to my object, whether any of the monkeys especially attacked each other by
the nape of the neck, I was answered that this was not the case, except
with the above baboon.  In the Hamadryas baboon, Ehrenberg compares the
mane of the adult male to that of a young lion, whilst in the young of both
sexes and in the female the mane is almost absent.

It appeared to me probable that the immense woolly mane of the male
American bison, which reaches almost to the ground, and is much more
developed in the males than in the females, served as a protection to them
in their terrible battles; but an experienced hunter told Judge Caton that
he had never observed anything which favoured this belief.  The stallion
has a thicker and fuller mane than the mare; and I have made particular
inquiries of two great trainers and breeders, who have had charge of many
entire horses, and am assured that they "invariably endeavour to seize one
another by the neck."  It does not, however, follow from the foregoing
statements, that when the hair on the neck serves as a defence, that it was
originally developed for this purpose, though this is probable in some
cases, as in that of the lion.  I am informed by Mr. McNeill that the long
hairs on the throat of the stag (Cervus elaphus) serve as a great
protection to him when hunted, for the dogs generally endeavour to seize
him by the throat; but it is not probable that these hairs were specially
developed for this purpose; otherwise the young and the females would have
been equally protected.

CHOICE IN PAIRING BY EITHER SEX OF QUADRUPEDS.

Before describing in the next chapter, the differences between the sexes in
voice, odours emitted, and ornaments, it will be convenient here to
consider whether the sexes exert any choice in their unions.  Does the
female prefer any particular male, either before or after the males may
have fought together for supremacy; or does the male, when not a
polygamist, select any particular female?  The general impression amongst
breeders seems to be that the male accepts any female; and this owing to
his eagerness, is, in most cases, probably the truth.  Whether the female
as a general rule indifferently accepts any male is much more doubtful.  In
the fourteenth chapter, on Birds, a considerable body of direct and
indirect evidence was advanced, shewing that the female selects her
partner; and it would be a strange anomaly if female quadrupeds, which
stand higher in the scale and have higher mental powers, did not generally,
or at least often, exert some choice.  The female could in most cases
escape, if wooed by a male that did not please or excite her; and when
pursued by several males, as commonly occurs, she would often have the
opportunity, whilst they were fighting together, of escaping with some one
male, or at least of temporarily pairing with him.  This latter contingency
has often been observed in Scotland with female red-deer, as I am informed
by Sir Philip Egerton and others.  (44. Mr. Boner, in his excellent
description of the habits of the red-deer in Germany ('Forest Creatures,'
1861, p. 81) says, "while the stag is defending his rights against one
intruder, another invades the sanctuary of his harem, and carries off
trophy after trophy."  Exactly the same thing occurs with seals; see Mr.
J.A. Allen, ibid. p. 100.)

It is scarcely possible that much should be known about female quadrupeds
in a state of nature making any choice in their marriage unions.  The
following curious details on the courtship of one of the eared seals
(Callorhinus ursinus) are given (45.  Mr. J.A. Allen in 'Bull. Mus. Comp.
Zoolog. of Cambridge, United States,' vol. ii. No. 1, p. 99.) on the
authority of Capt. Bryant, who had ample opportunities for observation.  He
says, "Many of the females on their arrival at the island where they breed
appear desirous of returning to some particular male, and frequently climb
the outlying rocks to overlook the rookeries, calling out and listening as
if for a familiar voice.  Then changing to another place they do the same
again...As soon as a female reaches the shore, the nearest male goes down
to meet her, making meanwhile a noise like the clucking of a hen to her
chickens.  He bows to her and coaxes her until he gets between her and the
water so that she cannot escape him.  Then his manner changes, and with a
harsh growl he drives her to a place in his harem.  This continues until
the lower row of harems is nearly full.  Then the males higher up select
the time when their more fortunate neighbours are off their guard to steal
their wives.  This they do by taking them in their mouths and lifting them
over the heads of the other females, and carefully placing them in their
own harem, carrying them as cats do their kittens.  Those still higher up
pursue the same method until the whole space is occupied.  Frequently a
struggle ensues between two males for the possession of the same female,
and both seizing her at once pull her in two or terribly lacerate her with
their teeth.  When the space is all filled, the old male walks around
complacently reviewing his family, scolding those who crowd or disturb the
others, and fiercely driving off all intruders.  This surveillance always
keeps him actively occupied."

As so little is known about the courtship of animals in a state of nature,
I have endeavoured to discover how far our domesticated quadrupeds evince
any choice in their unions.  Dogs offer the best opportunity for
observation, as they are carefully attended to and well understood.  Many
breeders have expressed a strong opinion on this head.  Thus, Mr. Mayhew
remarks, "The females are able to bestow their affections; and tender
recollections are as potent over them as they are known to be in other
cases, where higher animals are concerned.  Bitches are not always prudent
in their loves, but are apt to fling themselves away on curs of low degree.
If reared with a companion of vulgar appearance, there often springs up
between the pair a devotion which no time can afterwards subdue.  The
passion, for such it really is, becomes of a more than romantic endurance."
Mr. Mayhew, who attended chiefly to the smaller breeds, is convinced that
the females are strongly attracted by males of a large size.  (46.  'Dogs:
their Management,' by E. Mayhew, M.R.C.V.S., 2nd ed., 1864, pp. 187-192.)
The well-known veterinary Blaine states (47.  Quoted by Alex. Walker, 'On
Intermarriage,' 1838, p. 276; see also p. 244.) that his own female pug dog
became so attached to a spaniel, and a female setter to a cur, that in
neither case would they pair with a dog of their own breed until several
weeks had elapsed.  Two similar and trustworthy accounts have been given me
in regard to a female retriever and a spaniel, both of which became
enamoured with terrier-dogs.

Mr. Cupples informs me that he can personally vouch for the accuracy of the
following more remarkable case, in which a valuable and wonderfully-
intelligent female terrier loved a retriever belonging to a neighbour to
such a degree, that she had often to be dragged away from him.  After their
permanent separation, although repeatedly shewing milk in her teats, she
would never acknowledge the courtship of any other dog, and to the regret
of her owner never bore puppies. Mr. Cupples also states, that in 1868, a
female deerhound in his kennel thrice produced puppies, and on each
occasion shewed a marked preference for one of the largest and handsomest,
but not the most eager, of four deerhounds living with her, all in the
prime of life. Mr. Cupples has observed that the female generally favours a
dog whom she has associated with and knows; her shyness and timidity at
first incline her against a strange dog.  The male, on the contrary, seems
rather inclined towards strange females.  It appears to be rare when the
male refuses any particular female, but Mr. Wright, of Yeldersley House, a
great breeder of dogs, informs me that he has known some instances; he
cites the case of one of his own deerhounds, who would not take any notice
of a particular female mastiff, so that another deerhound had to be
employed.  It would be superfluous to give, as I could, other instances,
and I will only add that Mr. Barr, who has carefully bred many bloodhounds,
states that in almost every instance particular individuals of opposite
sexes shew a decided preference for each other.  Finally, Mr. Cupples,
after attending to this subject for another year, has written to me, "I
have had full confirmation of my former statement, that dogs in breeding
form decided preferences for each other, being often influenced by size,
bright colour, and individual characters, as well as by the degree of their
previous familiarity."

In regard to horses, Mr. Blenkiron, the greatest breeder of race-horses in
the world, informs me that stallions are so frequently capricious in their
choice, rejecting one mare and without any apparent cause taking to
another, that various artifices have to be habitually used.  The famous
Monarque, for instance, would never consciously look at the dam of
Gladiateur, and a trick had to be practised.  We can partly see the reason
why valuable race-horse stallions, which are in such demand as to be
exhausted, should be so particular in their choice.  Mr. Blenkiron has
never known a mare reject a horse; but this has occurred in Mr. Wright's
stable, so that the mare had to be cheated.  Prosper Lucas (48.  'Traite de
l'Hered. Nat.' tom. ii. 1850, p. 296.) quotes various statements from
French authorities, and remarks, "On voit des etalons qui s'eprennent d'une
jument, et negligent toutes les autres."  He gives, on the authority of
Baelen, similar facts in regard to bulls; and Mr. H. Reeks assures me that
a famous short-horn bull belonging to his father "invariably refused to be
matched with a black cow."  Hoffberg, in describing the domesticated
reindeer of Lapland says, "Foeminae majores et fortiores mares prae
caeteris admittunt, ad eos confugiunt, a junioribus agitatae, qui hos in
fugam conjiciunt."  (49.  'Amoenitates Acad.' vol. iv. 1788, p. 160.)  A
clergyman, who has bred many pigs, asserts that sows often reject one boar
and immediately accept another.

From these facts there can be no doubt that, with most of our domesticated
quadrupeds, strong individual antipathies and preferences are frequently
exhibited, and much more commonly by the female than by the male.  This
being the case, it is improbable that the unions of quadrupeds in a state
of nature should be left to mere chance.  It is much more probable that the
females are allured or excited by particular males, who possess certain
characters in a higher degree than other males; but what these characters
are, we can seldom or never discover with certainty.


CHAPTER XVIII.

SECONDARY SEXUAL CHARACTERS OF MAMMALS--continued.

Voice--Remarkable sexual peculiarities in seals--Odour--Development of the
hair--Colour of the hair and skin--Anomalous case of the female being more
ornamented than the male--Colour and ornaments due to sexual selection--
Colour acquired for the sake of protection--Colour, though common to both
sexes, often due to sexual selection--On the disappearance of spots and
stripes in adult quadrupeds--On the colours and ornaments of the
Quadrumana--Summary.

Quadrupeds use their voices for various purposes, as a signal of danger, as
a call from one member of a troop to another, or from the mother to her
lost offspring, or from the latter for protection to their mother; but such
uses need not here be considered.  We are concerned only with the
difference between the voices of the sexes, for instance between that of
the lion and lioness, or of the bull and cow.  Almost all male animals use
their voices much more during the rutting-season than at any other time;
and some, as the giraffe and porcupine (1.  Owen, 'Anatomy of Vertebrates,'
vol. iii. p. 585.), are said to be completely mute excepting at this
season.  As the throats (i.e. the larynx and thyroid bodies (2.  Ibid. p.
595.)) of stags periodically become enlarged at the beginning of the
breeding-season, it might be thought that their powerful voices must be
somehow of high importance to them; but this is very doubtful.  From
information given to me by two experienced observers, Mr. McNeill and Sir
P. Egerton, it seems that young stags under three years old do not roar or
bellow; and that the old ones begin bellowing at the commencement of the
breeding-season, at first only occasionally and moderately, whilst they
restlessly wander about in search of the females.  Their battles are
prefaced by loud and prolonged bellowing, but during the actual conflict
they are silent.  Animals of all kinds which habitually use their voices
utter various noises under any strong emotion, as when enraged and
preparing to fight; but this may merely be the result of nervous
excitement, which leads to the spasmodic contraction of almost all the
muscles of the body, as when a man grinds his teeth and clenches his fists
in rage or agony.  No doubt stags challenge each other to mortal combat by
bellowing; but those with the more powerful voices, unless at the same time
the stronger, better-armed, and more courageous, would not gain any
advantage over their rivals.

It is possible that the roaring of the lion may be of some service to him
by striking terror into his adversary; for when enraged he likewise erects
his mane and thus instinctively tries to make himself appear as terrible as
possible.  But it can hardly be supposed that the bellowing of the stag,
even if it be of service to him in this way, can have been important enough
to have led to the periodical enlargement of the throat.  Some writers
suggest that the bellowing serves as a call to the female; but the
experienced observers above quoted inform me that female deer do not search
for the male, though the males search eagerly for the females, as indeed
might be expected from what we know of the habits of other male quadrupeds.
The voice of the female, on the other hand, quickly brings to her one or
more stags (3.  See, for instance, Major W. Ross King ('The Sportsman in
Canada,' 1866, pp. 53, 131) on the habits of the moose and wild reindeer.),
as is well known to the hunters who in wild countries imitate her cry.  If
we could believe that the male had the power to excite or allure the female
by his voice, the periodical enlargement of his vocal organs would be
intelligible on the principle of sexual selection, together with
inheritance limited to the same sex and season; but we have no evidence in
favour of this view.  As the case stands, the loud voice of the stag during
the breeding-season does not seem to be of any special service to him,
either during his courtship or battles, or in any other way.  But may we
not believe that the frequent use of the voice, under the strong excitement
of love, jealousy, and rage, continued during many generations, may at last
have produced an inherited effect on the vocal organs of the stag, as well
as of other male animals?  This appears to me, in our present state of
knowledge, the most probable view.

The voice of the adult male gorilla is tremendous, and he is furnished with
a laryngeal sack, as is the adult male orang.  (4.  Owen 'Anatomy of
Vertebrates,' vol. iii. p. 600.)  The gibbons rank among the noisiest of
monkeys, and the Sumatra species (Hylobates syndactylus) is also furnished
with an air sack; but Mr. Blyth, who has had opportunities for observation,
does not believe that the male is noisier than the female.  Hence, these
latter monkeys probably use their voices as a mutual call; and this is
certainly the case with some quadrupeds, for instance the beaver.  (5.  Mr.
Green, in 'Journal of Linnean Society,' vol. x. 'Zoology,' 1869, note 362.)
Another gibbon, the H. agilis, is remarkable, from having the power of
giving a complete and correct octave of musical notes (6.  C.L. Martin,
'General Introduction to the Natural History of Mamm. Animals,' 1841, p.
431.), which we may reasonably suspect serves as a sexual charm; but I
shall have to recur to this subject in the next chapter.  The vocal organs
of the American Mycetes caraya are one-third larger in the male than in the
female, and are wonderfully powerful.  These monkeys in warm weather make
the forests resound at morning and evening with their overwhelming voices.
The males begin the dreadful concert, and often continue it during many
hours, the females sometimes joining in with their less powerful voices.
An excellent observer, Rengger (7.  'Naturgeschichte der Saeugethiere von
Paraguay,' 1830, ss. 15, 21.), could not perceive that they were excited to
begin by any special cause; he thinks that, like many birds, they delight
in their own music, and try to excel each other.  Whether most of the
foregoing monkeys have acquired their powerful voices in order to beat
their rivals and charm the females--or whether the vocal organs have been
strengthened and enlarged through the inherited effects of long-continued
use without any particular good being thus gained--I will not pretend to
say; but the former view, at least in the case of the Hylobates agilis,
seems the most probable.

I may here mention two very curious sexual peculiarities occurring in
seals, because they have been supposed by some writers to affect the voice.
The nose of the male sea-elephant (Macrorhinus proboscideus) becomes
greatly elongated during the breeding-season, and can then be erected.  In
this state it is sometimes a foot in length.  The female is not thus
provided at any period of life.  The male makes a wild, hoarse, gurgling
noise, which is audible at a great distance and is believed to be
strengthened by the proboscis; the voice of the female being different.
Lesson compares the erection of the proboscis, with the swelling of the
wattles of male gallinaceous birds whilst courting the females.  In another
allied kind of seal, the bladder-nose (Cystophora cristata), the head is
covered by a great hood or bladder.  This is supported by the septum of the
nose, which is produced far backwards and rises into an internal crest
seven inches in height.  The hood is clothed with short hair, and is
muscular; can be inflated until it more than equals the whole head in size!
The males when rutting, fight furiously on the ice, and their roaring "is
said to be sometimes so loud as to be heard four miles off."  When attacked
they likewise roar or bellow; and whenever irritated the bladder is
inflated and quivers.  Some naturalists believe that the voice is thus
strengthened, but various other uses have been assigned to this
extraordinary structure.  Mr. R. Brown thinks that it serves as a
protection against accidents of all kinds; but this is not probable, for,
as I am assured by Mr. Lamont who killed 600 of these animals, the hood is
rudimentary in the females, and it is not developed in the males during
youth.  (8.  On the sea-elephant, see an article by Lesson, in 'Dict.
Class. Hist. Nat.' tom. xiii. p. 418.  For the Cystophora, or Stemmatopus,
see Dr. Dekay, 'Annals of Lyceum of Nat. Hist.' New York, vol. i. 1824, p.
94.  Pennant has also collected information from the sealers on this
animal.  The fullest account is given by Mr. Brown, in 'Proc. Zoolog. Soc.'
1868, p. 435.)

ODOUR.

With some animals, as with the notorious skunk of America, the overwhelming
odour which they emit appears to serve exclusively as a defence.  With
shrew-mice (Sorex) both sexes possess abdominal scent-glands, and there can
be little doubt, from the rejection of their bodies by birds and beasts of
prey, that the odour is protective; nevertheless, the glands become
enlarged in the males during the breeding-season.  In many other quadrupeds
the glands are of the same size in both sexes (9.  As with the castoreum of
the beaver, see Mr. L.H. Morgan's most interesting work, 'The American
Beaver,' 1868, p. 300.  Pallas ('Spic. Zoolog.' fasc. viii. 1779, p. 23)
has well discussed the odoriferous glands of mammals.  Owen ('Anat. of
Vertebrates,' vol. iii. p. 634) also gives an account of these glands,
including those of the elephant, and (p. 763) those of shrew-mice.  On
bats, Mr. Dobson in 'Proceedings of the Zoological Society' 1873, p. 241.),
but their uses are not known.  In other species the glands are confined to
the males, or are more developed than in the females; and they almost
always become more active during the rutting-season.  At this period the
glands on the sides of the face of the male elephant enlarge, and emit a
secretion having a strong musky odour.  The males, and rarely the females,
of many kinds of bats have glands and protrudable sacks situated in various
parts; and it is believed that these are odoriferous.

The rank effluvium of the male goat is well known, and that of certain male
deer is wonderfully strong and persistent.  On the banks of the Plata I
perceived the air tainted with the odour of the male Cervus campestris, at
half a mile to leeward of a herd; and a silk handkerchief, in which I
carried home a skin, though often used and washed, retained, when first
unfolded, traces of the odour for one year and seven months.  This animal
does not emit its strong odour until more than a year old, and if castrated
whilst young never emits it.  (10.  Rengger, 'Naturgeschichte der
Saeugethiere von Paraguay,' 1830, s. 355.  This observer also gives some
curious particulars in regard to the odour.)  Besides the general odour,
permeating the whole body of certain ruminants (for instance, Bos
moschatus) in the breeding-season, many deer, antelopes, sheep, and goats
possess odoriferous glands in various situations, more especially on their
faces.  The so-called tear-sacks, or suborbital pits, come under this head.
These glands secrete a semi-fluid fetid matter which is sometimes so
copious as to stain the whole face, as I have myself seen in an antelope.
They are "usually larger in the male than in the female, and their
development is checked by castration."  (11.  Owen, 'Anatomy of
Vertebrates,' vol. iii. p. 632.  See also Dr. Murie's observations on those
glands in the 'Proc. Zoolog. Soc.' 1870, p. 340.  Desmarest, 'On the
Antilope subgutturosa, 'Mammalogie,' 1820, p. 455.)  According to Desmarest
they are altogether absent in the female of Antilope subgutturosa.  Hence,
there can be no doubt that they stand in close relation with the
reproductive functions.  They are also sometimes present, and sometimes
absent, in nearly allied forms.  In the adult male musk-deer (Moschus
moschiferus), a naked space round the tail is bedewed with an odoriferous
fluid, whilst in the adult female, and in the male until two years old,
this space is covered with hair and is not odoriferous.  The proper musk-
sack of this deer is from its position necessarily confined to the male,
and forms an additional scent-organ.  It is a singular fact that the matter
secreted by this latter gland, does not, according to Pallas, change in
consistence, or increase in quantity, during the rutting-season;
nevertheless this naturalist admits that its presence is in some way
connected with the act of reproduction.  He gives, however, only a
conjectural and unsatisfactory explanation of its use.  (12.  Pallas,
'Spicilegia Zoolog.' fasc. xiii. 1799, p. 24; Desmoulins, 'Dict. Class.
d'Hist. Nat.' tom. iii. p. 586.)

In most cases, when only the male emits a strong odour during the breeding-
season, it probably serves to excite or allure the female.  We must not
judge on this head by our own taste, for it is well known that rats are
enticed by certain essential oils, and cats by valerian, substances far
from agreeable to us; and that dogs, though they will not eat carrion,
sniff and roll on it.  From the reasons given when discussing the voice of
the stag, we may reject the idea that the odour serves to bring the females
from a distance to the males.  Active and long-continued use cannot here
have come into play, as in the case of the vocal organs.  The odour emitted
must be of considerable importance to the male, inasmuch as large and
complex glands, furnished with muscles for everting the sack, and for
closing or opening the orifice, have in some cases been developed.  The
development of these organs is intelligible through sexual selection, if
the most odoriferous males are the most successful in winning the females,
and in leaving offspring to inherit their gradually perfected glands and
odours.

DEVELOPMENT OF THE HAIR.

We have seen that male quadrupeds often have the hair on their necks and
shoulders much more developed than the females; and many additional
instances could be given.  This sometimes serves as a defence to the male
during his battles; but whether the hair in most cases has been specially
developed for this purpose, is very doubtful.  We may feel almost certain
that this is not the case, when only a thin and narrow crest runs along the
back; for a crest of this kind would afford scarcely any protection, and
the ridge of the back is not a place likely to be injured; nevertheless
such crests are sometimes confined to the males, or are much more developed
in them than in the females.  Two antelopes, the Tragelaphus scriptus (13.
Dr. Gray, 'Gleanings from the Menagerie at Knowsley,' pl. 28.) (Fig. 70)
and Portax picta may be given as instances.  When stags, and the males of
the wild goat, are enraged or terrified, these crests stand erect (14.
Judge Caton on the Wapiti, 'Transact. Ottawa Acad. Nat. Sciences,' 1868,
pp. 36, 40; Blyth, 'Land and Water,' on Capra aegagrus 1867, p. 37.); but
it cannot be supposed that they have been developed merely for the sake of
exciting fear in their enemies.  One of the above-named antelopes, the
Portax picta, has a large well-defined brush of black hair on the throat,
and this is much larger in the male than in the female.  In the Ammotragus
tragelaphus of North Africa, a member of the sheep-family, the fore-legs
are almost concealed by an extraordinary growth of hair, which depends from
the neck and upper halves of the legs; but Mr. Bartlett does not believe
that this mantle is of the least use to the male, in whom it is much more
developed than in the female.

[Fig. 68.  Pithecia satanas, male (from Brehm).]

Male quadrupeds of many kinds differ from the females in having more hair,
or hair of a different character, on certain parts of their faces.  Thus
the bull alone has curled hair on the forehead.  (15.  Hunter's 'Essays and
Observations,' edited by Owen, 1861. vol. i. p. 236.)  In three closely-
allied sub-genera of the goat family, only the males possess beards,
sometimes of large size; in two other sub-genera both sexes have a beard,
but it disappears in some of the domestic breeds of the common goat; and
neither sex of the Hemitragus has a beard.  In the ibex the beard is not
developed during the summer, and is so small at other times that it may be
called rudimentary.  (16.  See Dr. Gray's 'Catalogue of Mammalia in the
British Museum,' part iii. 1852, p. 144.)  With some monkeys the beard is
confined to the male, as in the orang; or is much larger in the male than
in the female, as in the Mycetes caraya and Pithecia satanas (Fig. 68).  So
it is with the whiskers of some species of Macacus (17.  Rengger,
'Saeugethiere,' etc., s. 14; Desmarest, 'Mammalogie,' p. 86.), and, as we
have seen, with the manes of some species of baboons.  But with most kinds
of monkeys the various tufts of hair about the face and head are alike in
both sexes.

The males of various members of the ox family (Bovidae), and of certain
antelopes, are furnished with a dewlap, or great fold of skin on the neck,
which is much less developed in the female.

Now, what must we conclude with respect to such sexual differences as
these?  No one will pretend that the beards of certain male goats, or the
dewlaps of the bull, or the crests of hair along the backs of certain male
antelopes, are of any use to them in their ordinary habits.  It is possible
that the immense beard of the male Pithecia, and the large beard of the
male orang, may protect their throats when fighting; for the keepers in the
Zoological Gardens inform me that many monkeys attack each other by the
throat; but it is not probable that the beard has been developed for a
distinct purpose from that served by the whiskers, moustache, and other
tufts of hair on the face; and no one will suppose that these are useful as
a protection.  Must we attribute all these appendages of hair or skin to
mere purposeless variability in the male?  It cannot be denied that this is
possible; for in many domesticated quadrupeds, certain characters,
apparently not derived through reversion from any wild parent form, are
confined to the males, or are more developed in them than in the females--
for instance, the hump on the male zebu-cattle of India, the tail of fat-
tailed rams, the arched outline of the forehead in the males of several
breeds of sheep, and lastly, the mane, the long hairs on the hind legs, and
the dewlap of the male of the Berbura goat.  (18.  See the chapters on
these several animals in vol. i. of my 'Variation of Animals under
Domestication;' also vol. ii. p. 73; also chap. xx. on the practice of
selection by semi-civilised people.  For the Berbura goat, see Dr. Gray,
'Catalogue,' ibid. p. 157.)  The mane, which occurs only in the rams of an
African breed of sheep, is a true secondary sexual character, for, as I
hear from Mr. Winwood Reade, it is not developed if the animal be
castrated.  Although we ought to be extremely cautious, as shewn in my work
on 'Variation under Domestication,' in concluding that any character, even
with animals kept by semi-civilised people, has not been subjected to
selection by man, and thus augmented, yet in the cases just specified this
is improbable; more especially as the characters are confined to the males,
or are more strongly developed in them than in the females.  If it were
positively known that the above African ram is a descendant of the same
primitive stock as the other breeds of sheep, and if the Berbura male-goat
with his mane, dewlap, etc., is descended from the same stock as other
goats, then, assuming that selection has not been applied to these
characters, they must be due to simple variability, together with sexually-
limited inheritance.

Hence it appears reasonable to extend this same view to all analogous cases
with animals in a state of nature.  Nevertheless I cannot persuade myself
that it generally holds good, as in the case of the extraordinary
development of hair on the throat and fore-legs of the male Ammotragus, or
in that of the immense beard of the male Pithecia.  Such study as I have
been able to give to nature makes me believe that parts or organs which are
highly developed, were acquired at some period for a special purpose.  With
those antelopes in which the adult male is more strongly-coloured than the
female, and with those monkeys in which the hair on the face is elegantly
arranged and coloured in a diversified manner, it seems probable that the
crests and tufts of hair were gained as ornaments; and this I know is the
opinion of some naturalists.  If this be correct, there can be little doubt
that they were gained or at least modified through sexual selection; but
how far the same view may be extended to other mammals is doubtful.

COLOUR OF THE HAIR AND OF THE NAKED SKIN.

I will first give briefly all the cases known to me of male quadrupeds
differing in colour from the females.  With Marsupials, as I am informed by
Mr. Gould, the sexes rarely differ in this respect; but the great red
kangaroo offers a striking exception, "delicate blue being the prevailing
tint in those parts of the female which in the male are red."  (19.
Osphranter rufus, Gould, 'Mammals of Australia,' 1863, vol. ii.  On the
Didelphis, Desmarest, 'Mammalogie,' p. 256.)  In the Didelphis opossum of
Cayenne the female is said to be a little more red than the male.  Of the
Rodents, Dr. Gray remarks:  "African squirrels, especially those found in
the tropical regions, have the fur much brighter and more vivid at some
seasons of the year than at others, and the fur of the male is generally
brighter than that of the female."  (20.  'Annals and Magazine of Natural
History,' Nov. 1867, p. 325.  On the Mus minutus, Desmarest, 'Mammalogie,'
p. 304.)  Dr. Gray informs me that he specified the African squirrels,
because, from their unusually bright colours, they best exhibit this
difference.  The female of the Mus minutus of Russia is of a paler and
dirtier tint than the male.  In a large number of bats the fur of the male
is lighter than in the female.  (21.  J.A. Allen, in 'Bulletin of Mus.
Comp. Zoolog. of Cambridge, United States,' 1869, p. 207.  Mr. Dobson on
sexual characters in the Chiroptera, 'Proceedings of the Zoological
Society,' 1873, p. 241.  Dr. Gray on Sloths, ibid. 1871, p. 436.)  Mr.
Dobson also remarks, with respect to these animals:  "Differences,
depending partly or entirely on the possession by the male of fur of a much
more brilliant hue, or distinguished by different markings or by the
greater length of certain portions, are met only, to any appreciable
extent, in the frugivorous bats in which the sense of sight is well
developed."  This last remark deserves attention, as bearing on the
question whether bright colours are serviceable to male animals from being
ornamental.  In one genus of sloths, it is now established, as Dr. Gray
states, "that the males are ornamented differently from the females--that
is to say, that they have a patch of soft short hair between the shoulders,
which is generally of a more or less orange colour, and in one species pure
white.  The females, on the contrary, are destitute of this mark."

The terrestrial Carnivora and Insectivora rarely exhibit sexual differences
of any kind, including colour.  The ocelot (Felis pardalis), however, is
exceptional, for the colours of the female, compared with those of the
male, are "moins apparentes, le fauve, etant plus terne, le blanc moins
pur, les raies ayant moins de largeur et les taches moins de diametre."
(22.  Desmarest, 'Mammalogie,' 1820, p. 220.  On Felis mitis, Rengger,
ibid. s. 194.)  The sexes of the allied Felis mitis also differ, but in a
less degree; the general hues of the female being rather paler than in the
male, with the spots less black.  The marine Carnivora or seals, on the
other hand, sometimes differ considerably in colour, and they present, as
we have already seen, other remarkable sexual differences.  Thus the male
of the Otaria nigrescens of the southern hemisphere is of a rich brown
shade above; whilst the female, who acquires her adult tints earlier in
life than the male, is dark-grey above, the young of both sexes being of a
deep chocolate colour.  The male of the northern Phoca groenlandica is
tawny grey, with a curious saddle-shaped dark mark on the back; the female
is much smaller, and has a very different appearance, being "dull white or
yellowish straw-colour, with a tawny hue on the back"; the young at first
are pure white, and can "hardly be distinguished among the icy hummocks and
snow, their colour thus acting as a protection."  (23.  Dr. Murie on the
Otaria, 'Proceedings Zoological Society,' 1869, p. 108.  Mr. R. Brown on
the P. groenlandica, ibid. 1868, p. 417.  See also on the colours of seals,
Desmarest, ibid. pp. 243, 249.)

With Ruminants sexual differences of colour occur more commonly than in any
other order.  A difference of this kind is general in the Strepsicerene
antelopes; thus the male nilghau (Portax picta) is bluish-grey and much
darker than the female, with the square white patch on the throat, the
white marks on the fetlocks, and the black spots on the ears all much more
distinct.  We have seen that in this species the crests and tufts of hair
are likewise more developed in the male than in the hornless female.  I am
informed by Mr. Blyth that the male, without shedding his hair,
periodically becomes darker during the breeding-season.  Young males cannot
be distinguished from young females until about twelve months old; and if
the male is emasculated before this period, he never, according to the same
authority, changes colour.  The importance of this latter fact, as evidence
that the colouring of the Portax is of sexual origin, becomes obvious, when
we hear (24.  Judge Caton, in 'Transactions of the Ottawa Academy of
Natural Sciences,' 1868, p. 4.) that neither the red summer-coat nor the
blue winter-coat of the Virginian deer is at all affected by emasculation.
With most or all of the highly-ornamented species of Tragelaphus the males
are darker than the hornless females, and their crests of hair are more
fully developed.  In the male of that magnificent antelope, the Derbyan
eland, the body is redder, the whole neck much blacker, and the white band
which separates these colours broader than in the female.  In the Cape
eland, also, the male is slightly darker than the female.  (25.  Dr. Gray,
'Cat. of Mamm. in Brit. Mus.' part iii. 1852, pp. 134-142; also Dr. Gray,
'Gleanings from the Menagerie of Knowsley,' in which there is a splendid
drawing of the Oreas derbianus:  see the text on Tragelaphus.  For the Cape
eland (Oreas canna), see Andrew Smith, 'Zoology of S. Africa,' pl. 41 and
42.  There are also many of these Antelopes in the Zoological Gardens.)

In the Indian black-buck (A. bezoartica), which belongs to another tribe of
antelopes, the male is very dark, almost black; whilst the hornless female
is fawn-coloured.  We meet in this species, as Mr. Blyth informs me, with
an exactly similar series of facts, as in the Portax picta, namely, in the
male periodically changing colour during the breeding-season, in the
effects of emasculation on this change, and in the young of both sexes
being indistinguishable from each other.  In the Antilope niger the male is
black, the female, as well as the young of both sexes, being brown; in A.
sing-sing the male is much brighter coloured than the hornless female, and
his chest and belly are blacker; in the male A. caama, the marks and lines
which occur on various parts of the body are black, instead of brown as in
the female; in the brindled gnu (A. gorgon) "the colours of the male are
nearly the same as those of the female, only deeper and of a brighter hue."
(26.  On the Ant. niger, see 'Proc. Zool. Soc.' 1850, p. 133.  With respect
to an allied species, in which there is an equal sexual difference in
colour, see Sir S. Baker, 'The Albert Nyanza,' 1866, vol. ii. p. 627.  For
the A. sing-sing, Gray, 'Cat. B. Mus.' p. 100.  Desmarest, 'Mammalogie,' p.
468, on the A. caama.  Andrew Smith, 'Zoology of S. Africa,' on the Gnu.)
Other analogous cases could be added.

The Banteng bull (Bos sondaicus) of the Malayan Archipelago is almost
black, with white legs and buttocks; the cow is of a bright dun, as are the
young males until about the age of three years, when they rapidly change
colour.  The emasculated bull reverts to the colour of the female.  The
female Kemas goat is paler, and both it and the female Capra aegagrus are
said to be more uniformly tinted than their males.  Deer rarely present any
sexual differences in colour.  Judge Caton, however, informs me that in the
males of the wapiti deer (Cervus canadensis) the neck, belly, and legs are
much darker than in the female; but during the winter the darker tints
gradually fade away and disappear.  I may here mention that Judge Caton has
in his park three races of the Virginian deer, which differ slightly in
colour, but the differences are almost exclusively confined to the blue
winter or breeding-coat; so that this case may be compared with those given
in a previous chapter of closely-allied or representative species of birds,
which differ from each other only in their breeding plumage.  (27.  'Ottawa
Academy of Sciences,' May 21, 1868, pp. 3, 5.)  The females of Cervus
paludosus of S. America, as well as the young of both sexes, do not possess
the black stripes on the nose and the blackish-brown line on the breast,
which are characteristic of the adult males.  (28.  S. Muller, on the
Banteng, 'Zoog. Indischen Archipel.' 1839-1844, tab. 35; see also Raffles,
as quoted by Mr. Blyth, in 'Land and Water,' 1867, p. 476.  On goats, Dr.
Gray, 'Catalogue of the British Museum,' p. 146; Desmarest, 'Mammalogie,'
p. 482.  On the Cervus paludosus, Rengger, ibid. s. 345.)  Lastly, as I am
informed by Mr. Blyth, the mature male of the beautifully coloured and
spotted axis deer is considerably darker than the female:  and this hue the
castrated male never acquires.

The last Order which we need consider is that of the Primates.  The male of
the Lemur macaco is generally coal-black, whilst the female is brown.  (29.
Sclater, 'Proc. Zool. Soc.' 1866, p. i.  The same fact has also been fully
ascertained by MM. Pollen and van Dam.  See, also, Dr. Gray in 'Annals and
Magazine of Natural History,' May 1871, p. 340.)  Of the Quadrumana of the
New World, the females and young of Mycetes caraya are greyish-yellow and
like each other; in the second year the young male becomes reddish-brown;
in the third, black, excepting the stomach, which, however, becomes quite
black in the fourth or fifth year.  There is also a strongly-marked
difference in colour between the sexes of Mycetes seniculus and Cebus
capucinus; the young of the former, and I believe of the latter species,
resembling the females.  With Pithecia leucocephala the young likewise
resemble the females, which are brownish-black above and light rusty-red
beneath, the adult males being black.  The ruff of hair round the face of
Ateles marginatus is tinted yellow in the male and white in the female.
Turning to the Old World, the males of Hylobates hoolock are always black,
with the exception of a white band over the brows; the females vary from
whity-brown to a dark tint mixed with black, but are never wholly black.
(30.  On Mycetes, Rengger, ibid. s. 14; and Brehm, 'Thierleben,' B. i. s.
96, 107.  On Ateles Desmarest, 'Mammalogie,' p. 75.  On Hylobates, Blyth,
'Land and Water,' 1867, p. 135.  On the Semnopithecus, S. Muller, 'Zoog.
Indischen Archipel.' tab. x.)  In the beautiful Cercopithecus diana, the
head of the adult male is of an intense black, whilst that of the female is
dark grey; in the former the fur between the thighs is of an elegant fawn-
colour, in the latter it is paler.  In the beautiful and curious moustache
monkey (Cercopithecus cephus) the only difference between the sexes is that
the tail of the male is chestnut and that of the female grey; but Mr.
Bartlett informs me that all the hues become more pronounced in the male
when adult, whilst in the female they remain as they were during youth.
According to the coloured figures given by Solomon Muller, the male of
Semnopithecus chrysomelas is nearly black, the female being pale brown.  In
the Cercopithecus cynosurus and griseo-viridis one part of the body, which
is confined to the male sex, is of the most brilliant blue or green, and
contrasts strikingly with the naked skin on the hinder part of the body,
which is vivid red.

[Fig. 69.  Head of male Mandrill (from Gervais, 'Hist. Nat. des
Mammiferes').]

Lastly, in the baboon family, the adult male of Cynocephalus hamadryas
differs from the female not only by his immense mane, but slightly in the
colour of the hair and of the naked callosities.  In the drill (C.
leucophaeus) the females and young are much paler-coloured, with less
green, than the adult males.  No other member in the whole class of mammals
is coloured in so extraordinary a manner as the adult male mandrill (C.
mormon).  The face at this age becomes of a fine blue, with the ridge and
tip of the nose of the most brilliant red.  According to some authors, the
face is also marked with whitish stripes, and is shaded in parts with
black, but the colours appear to be variable.  On the forehead there is a
crest of hair, and on the chin a yellow beard.  "Toutes les parties
superieures de leurs cuisses et le grand espace nu de leurs fesses sont
egalement colores du rouge le plus vif, avec un melange de bleu qui ne
manque reellement pas d'elegance."  (31.  Gervais, 'Hist. Nat. des
Mammiferes,' 1854, p. 103.  Figures are given of the skull of the male.
Also Desmarest, 'Mammalogie,' p. 70.  Geoffroy St.-Hilaire and F. Cuvier,
'Hist. Nat. des Mammiferes,' 1824, tom. i.)  When the animal is excited all
the naked parts become much more vividly tinted.  Several authors have used
the strongest expressions in describing these resplendent colours, which
they compare with those of the most brilliant birds.  Another remarkable
peculiarity is that when the great canine teeth are fully developed,
immense protuberances of bone are formed on each cheek, which are deeply
furrowed longitudinally, and the naked skin over them is brilliantly-
coloured, as just-described.  (Fig. 69.)  In the adult females and in the
young of both sexes these protuberances are scarcely perceptible; and the
naked parts are much less bright coloured, the face being almost black,
tinged with blue.  In the adult female, however, the nose at certain
regular intervals of time becomes tinted with red.

In all the cases hitherto given the male is more strongly or brighter
coloured than the female, and differs from the young of both sexes.  But as
with some few birds it is the female which is brighter coloured than the
male, so with the Rhesus monkey (Macacus rhesus), the female has a large
surface of naked skin round the tail, of a brilliant carmine red, which, as
I was assured by the keepers in the Zoological Gardens, periodically
becomes even yet more vivid, and her face also is pale red.  On the other
hand, in the adult male and in the young of both sexes (as I saw in the
Gardens), neither the naked skin at the posterior end of the body, nor the
face, shew a trace of red.  It appears, however, from some published
accounts, that the male does occasionally, or during certain seasons,
exhibit some traces of the red.  Although he is thus less ornamented than
the female, yet in the larger size of his body, larger canine teeth, more
developed whiskers, more prominent superciliary ridges, he follows the
common rule of the male excelling the female.

I have now given all the cases known to me of a difference in colour
between the sexes of mammals.  Some of these may be the result of
variations confined to one sex and transmitted to the same sex, without any
good being gained, and therefore without the aid of selection.  We have
instances of this with our domesticated animals, as in the males of certain
cats being rusty-red, whilst the females are tortoise-shell coloured.
Analogous cases occur in nature:  Mr. Bartlett has seen many black
varieties of the jaguar, leopard, vulpine phalanger, and wombat; and he is
certain that all, or nearly all these animals, were males.  On the other
hand, with wolves, foxes, and apparently American squirrels, both sexes are
occasionally born black.  Hence it is quite possible that with some mammals
a difference in colour between the sexes, especially when this is
congenital, may simply be the result, without the aid of selection, of the
occurrence of one or more variations, which from the first were sexually
limited in their transmission.  Nevertheless it is improbable that the
diversified, vivid, and contrasted colours of certain quadrupeds, for
instance, of the above monkeys and antelopes, can thus be accounted for.
We should bear in mind that these colours do not appear in the male at
birth, but only at or near maturity; and that unlike ordinary variations,
they are lost if the male be emasculated.  It is on the whole probable that
the strongly-marked colours and other ornamental characters of male
quadrupeds are beneficial to them in their rivalry with other males, and
have consequently been acquired through sexual selection.  This view is
strengthened by the differences in colour between the sexes occurring
almost exclusively, as may be collected from the previous details, in those
groups and sub-groups of mammals which present other and strongly-marked
secondary sexual characters; these being likewise due to sexual selection.

Quadrupeds manifestly take notice of colour.  Sir S. Baker repeatedly
observed that the African elephant and rhinoceros attacked white or grey
horses with special fury.  I have elsewhere shewn (32.  The 'Variation of
Animals and Plants under Domestication,' 1868, vol. ii. pp. 102, 103.) that
half-wild horses apparently prefer to pair with those of the same colour,
and that herds of fallow-deer of different colours, though living together,
have long kept distinct.  It is a more significant fact that a female zebra
would not admit the addresses of a male ass until he was painted so as to
resemble a zebra, and then, as John Hunter remarks, "she received him very
readily.  In this curious fact, we have instinct excited by mere colour,
which had so strong an effect as to get the better of everything else.  But
the male did not require this, the female being an animal somewhat similar
to himself, was sufficient to rouse him."  (33.  'Essays and Observations,'
by J. Hunter, edited by Owen, 1861, vol. i. p. 194.)

In an earlier chapter we have seen that the mental powers of the higher
animals do not differ in kind, though greatly in degree, from the
corresponding powers of man, especially of the lower and barbarous races;
and it would appear that even their taste for the beautiful is not widely
different from that of the Quadrumana.  As the negro of Africa raises the
flesh on his face into parallel ridges "or cicatrices, high above the
natural surface, which unsightly deformities are considered great personal
attractions" (34.  Sir S. Baker, 'The Nile Tributaries of Abyssinia,'
1867.);--as negroes and savages in many parts of the world paint their
faces with red, blue, white, or black bars,--so the male mandrill of Africa
appears to have acquired his deeply-furrowed and gaudily-coloured face from
having been thus rendered attractive to the female.  No doubt it is to us a
most grotesque notion that the posterior end of the body should be coloured
for the sake of ornament even more brilliantly than the face; but this is
not more strange than that the tails of many birds should be especially
decorated.

With mammals we do not at present possess any evidence that the males take
pains to display their charms before the female; and the elaborate manner
in which this is performed by male birds and other animals is the strongest
argument in favour of the belief that the females admire, or are excited
by, the ornaments and colours displayed before them.  There is, however, a
striking parallelism between mammals and birds in all their secondary
sexual characters, namely in their weapons for fighting with rival males,
in their ornamental appendages, and in their colours.  In both classes,
when the male differs from the female, the young of both sexes almost
always resemble each other, and in a large majority of cases resemble the
adult female.  In both classes the male assumes the characters proper to
his sex shortly before the age of reproduction; and if emasculated at an
early period, loses them.  In both classes the change of colour is
sometimes seasonal, and the tints of the naked parts sometimes become more
vivid during the act of courtship.  In both classes the male is almost
always more vividly or strongly coloured than the female, and is ornamented
with larger crests of hair or feathers, or other such appendages.  In a few
exceptional cases the female in both classes is more highly ornamented than
the male.  With many mammals, and at least in the case of one bird, the
male is more odoriferous than the female.  In both classes the voice of the
male is more powerful than that of the female.  Considering this
parallelism, there can be little doubt that the same cause, whatever it may
be, has acted on mammals and birds; and the result, as far as ornamental
characters are concerned, may be attributed, as it appears to me, to the
long-continued preference of the individuals of one sex for certain
individuals of the opposite sex, combined with their success in leaving a
larger number of offspring to inherit their superior attractions.

EQUAL TRANSMISSION OF ORNAMENTAL CHARACTERS TO BOTH SEXES.

With many birds, ornaments, which analogy leads us to believe were
primarily acquired by the males, have been transmitted equally, or almost
equally, to both sexes; and we may now enquire how far this view applies to
mammals.  With a considerable number of species, especially of the smaller
kinds, both sexes have been coloured, independently of sexual selection,
for the sake of protection; but not, as far as I can judge, in so many
cases, nor in so striking a manner, as in most of the lower classes.
Audubon remarks that he often mistook the musk-rat (35.  Fiber zibethicus,
Audubon and Bachman, 'The Quadrupeds of North America,' 1846, p. 109.),
whilst sitting on the banks of a muddy stream, for a clod of earth, so
complete was the resemblance.  The hare on her form is a familiar instance
of concealment through colour; yet this principle partly fails in a
closely-allied species, the rabbit, for when running to its burrow, it is
made conspicuous to the sportsman, and no doubt to all beasts of prey, by
its upturned white tail.  No one doubts that the quadrupeds inhabiting
snow-clad regions have been rendered white to protect them from their
enemies, or to favour their stealing on their prey.  In regions where snow
never lies for long, a white coat would be injurious; consequently, species
of this colour are extremely rare in the hotter parts of the world.  It
deserves notice that many quadrupeds inhabiting moderately cold regions,
although they do not assume a white winter dress, become paler during this
season; and this apparently is the direct result of the conditions to which
they have long been exposed.  Pallas (36.  'Novae species Quadrupedum e
Glirium ordine,' 1778, p. 7.  What I have called the roe is the Capreolus
sibiricus subecaudatus of Pallas.) states that in Siberia a change of this
nature occurs with the wolf, two species of Mustela, the domestic horse,
the Equus hemionus, the domestic cow, two species of antelopes, the musk-
deer, the roe, elk, and reindeer.  The roe, for instance, has a red summer
and a greyish-white winter coat; and the latter may perhaps serve as a
protection to the animal whilst wandering through the leafless thickets,
sprinkled with snow and hoar-frost.  If the above-named animals were
gradually to extend their range into regions perpetually covered with snow,
their pale winter-coats would probably be rendered through natural
selection, whiter and whiter, until they became as white as snow.

Mr. Reeks has given me a curious instance of an animal profiting by being
peculiarly coloured.  He raised from fifty to sixty white and brown piebald
rabbits in a large walled orchard; and he had at the same time some
similarly coloured cats in his house.  Such cats, as I have often noticed,
are very conspicuous during day; but as they used to lie in watch during
the dusk at the mouths of the burrows, the rabbits apparently did not
distinguish them from their parti-coloured brethren.  The result was that,
within eighteen months, every one of these parti-coloured rabbits was
destroyed; and there was evidence that this was effected by the cats.
Colour seems to be advantageous to another animal, the skunk, in a manner
of which we have had many instances in other classes.  No animal will
voluntarily attack one of these creatures on account of the dreadful odour
which it emits when irritated; but during the dusk it would not easily be
recognised and might be attacked by a beast of prey.  Hence it is, as Mr.
Belt believes (37.  'The Naturalist in Nicaragua,' p. 249.), that the skunk
is provided with a great white bushy tail, which serves as a conspicuous
warning.

[Fig. 70.  Tragelaphus scriptus, male (from the Knowsley Menagerie).

Fig. 71.  Damalis pygarga, male (from the Knowsley Menagerie).]

Although we must admit that many quadrupeds have received their present
tints either as a protection, or as an aid in procuring prey, yet with a
host of species, the colours are far too conspicuous and too singularly
arranged to allow us to suppose that they serve for these purposes.  We may
take as an illustration certain antelopes; when we see the square white
patch on the throat, the white marks on the fetlocks, and the round black
spots on the ears, all more distinct in the male of the Portax picta, than
in the female;--when we see that the colours are more vivid, that the
narrow white lines on the flank and the broad white bar on the shoulder are
more distinct in the male Oreas derbyanus than in the female;--when we see
a similar difference between the sexes of the curiously-ornamented
Tragelaphus scriptus (Fig. 70),--we cannot believe that differences of this
kind are of any service to either sex in their daily habits of life.  It
seems a much more probable conclusion that the various marks were first
acquired by the males and their colours intensified through sexual
selection, and then partially transferred to the females.  If this view be
admitted, there can be little doubt that the equally singular colours and
marks of many other antelopes, though common to both sexes, have been
gained and transmitted in a like manner.  Both sexes, for instance, of the
koodoo (Strepsiceros kudu) (Fig. 64) have narrow white vertical lines on
their hind flanks, and an elegant angular white mark on their foreheads.
Both sexes in the genus Damalis are very oddly coloured; in D. pygarga the
back and neck are purplish-red, shading on the flanks into black; and these
colours are abruptly separated from the white belly and from a large white
space on the buttocks; the head is still more oddly coloured, a large
oblong white mask, narrowly-edged with black, covers the face up to the
eyes (Fig. 71); there are three white stripes on the forehead, and the ears
are marked with white.  The fawns of this species are of a uniform pale
yellowish-brown.  In Damalis albifrons the colouring of the head differs
from that in the last species in a single white stripe replacing the three
stripes, and in the ears being almost wholly white.  (38.  See the fine
plates in A. Smith's 'Zoology of South Africa,' and Dr. Gray's 'Gleanings
from the Menagerie of Knowsley.')  After having studied to the best of my
ability the sexual differences of animals belonging to all classes, I
cannot avoid the conclusion that the curiously-arranged colours of many
antelopes, though common to both sexes, are the result of sexual selection
primarily applied to the male.

The same conclusion may perhaps be extended to the tiger, one of the most
beautiful animals in the world, the sexes of which cannot be distinguished
by colour, even by the dealers in wild beasts.  Mr. Wallace believes (39.
'Westminster Review,' July 1, 1867, p. 5.) that the striped coat of the
tiger "so assimilates with the vertical stems of the bamboo, as to assist
greatly in concealing him from his approaching prey."  But this view does
not appear to me satisfactory.  We have some slight evidence that his
beauty may be due to sexual selection, for in two species of Felis the
analogous marks and colours are rather brighter in the male than in the
female.  The zebra is conspicuously striped, and stripes cannot afford any
protection in the open plains of South Africa.  Burchell (40.  'Travels in
South Africa,' 1824, vol. ii. p. 315.) in describing a herd says, "their
sleek ribs glistened in the sun, and the brightness and regularity of their
striped coats presented a picture of extraordinary beauty, in which
probably they are not surpassed by any other quadruped."  But as throughout
the whole group of the Equidae the sexes are identical in colour, we have
here no evidence of sexual selection.  Nevertheless he who attributes the
white and dark vertical stripes on the flanks of various antelopes to this
process, will probably extend the same view to the Royal Tiger and
beautiful Zebra.

We have seen in a former chapter that when young animals belonging to any
class follow nearly the same habits of life as their parents, and yet are
coloured in a different manner, it may be inferred that they have retained
the colouring of some ancient and extinct progenitor.  In the family of
pigs, and in the tapirs, the young are marked with longitudinal stripes,
and thus differ from all the existing adult species in these two groups.
With many kinds of deer the young are marked with elegant white spots, of
which their parents exhibit not a trace.  A graduated series can be
followed from the axis deer, both sexes of which at all ages and during all
seasons are beautifully spotted (the male being rather more strongly
coloured than the female), to species in which neither the old nor the
young are spotted.  I will specify some of the steps in this series.  The
Mantchurian deer (Cervus mantchuricus) is spotted during the whole year,
but, as I have seen in the Zoological Gardens, the spots are much plainer
during the summer, when the general colour of the coat is lighter, than
during the winter, when the general colour is darker and the horns are
fully developed.  In the hog-deer (Hyelaphus porcinus) the spots are
extremely conspicuous during the summer when the coat is reddish-brown, but
quite disappear during the winter when the coat is brown.  (41.  Dr. Gray,
'Gleanings from the Menagerie of Knowsley,' p. 64.  Mr. Blyth, in speaking
('Land and Water,' 1869, p. 42) of the hog-deer of Ceylon, says it is more
brightly spotted with white than the common hog-deer, at the season when it
renews its horns.)  In both these species the young are spotted.  In the
Virginian deer the young are likewise spotted, and about five per cent. of
the adult animals living in Judge Caton's park, as I am informed by him,
temporarily exhibit at the period when the red summer coat is being
replaced by the bluish winter coat, a row of spots on each flank, which are
always the same in number, though very variable in distinctness.  From this
condition there is but a very small step to the complete absence of spots
in the adults at all seasons; and, lastly, to their absence at all ages and
seasons, as occurs with certain species.  From the existence of this
perfect series, and more especially from the fawns of so many species being
spotted, we may conclude that the now living members of the deer family are
the descendants of some ancient species which, like the axis deer, was
spotted at all ages and seasons.  A still more ancient progenitor probably
somewhat resembled the Hyomoschus aquaticus--for this animal is spotted,
and the hornless males have large exserted canine teeth, of which some few
true deer still retain rudiments.  Hyomoschus, also, offers one of those
interesting cases of a form linking together two groups, for it is
intermediate in certain osteological characters between the pachyderms and
ruminants, which were formerly thought to be quite distinct.  (42.
Falconer and Cautley, 'Proc. Geolog. Soc.' 1843; and Falconer's 'Pal.
Memoirs,' vol. i. p. 196.)

A curious difficulty here arises.  If we admit that coloured spots and
stripes were first acquired as ornaments, how comes it that so many
existing deer, the descendants of an aboriginally spotted animal, and all
the species of pigs and tapirs, the descendants of an aboriginally striped
animal, have lost in their adult state their former ornaments?  I cannot
satisfactorily answer this question.  We may feel almost sure that the
spots and stripes disappeared at or near maturity in the progenitors of our
existing species, so that they were still retained by the young; and, owing
to the law of inheritance at corresponding ages, were transmitted to the
young of all succeeding generations.  It may have been a great advantage to
the lion and puma, from the open nature of their usual haunts, to have lost
their stripes, and to have been thus rendered less conspicuous to their
prey; and if the successive variations, by which this end was gained,
occurred rather late in life, the young would have retained their stripes,
as is now the case.  As to deer, pigs, and tapirs, Fritz Mueller has
suggested to me that these animals, by the removal of their spots or
stripes through natural selection, would have been less easily seen by
their enemies; and that they would have especially required this
protection, as soon as the carnivora increased in size and number during
the tertiary periods.  This may be the true explanation, but it is rather
strange that the young should not have been thus protected, and still more
so that the adults of some species should have retained their spots, either
partially or completely, during part of the year.  We know that, when the
domestic ass varies and becomes reddish-brown, grey, or black, the stripes
on the shoulders and even on the spine frequently disappear, though we
cannot explain the cause.  Very few horses, except dun-coloured kinds, have
stripes on any part of their bodies, yet we have good reason to believe
that the aboriginal horse was striped on the legs and spine, and probably
on the shoulders.  (43.  The 'Variation of Animals and Plants under
Domestication,' 1868, vol. i. pp. 61-64.)  Hence the disappearance of the
spots and stripes in our adult existing deer, pigs, and tapirs, may be due
to a change in the general colour of their coats; but whether this change
was effected through sexual or natural selection, or was due to the direct
action of the conditions of life, or to some other unknown cause, it is
impossible to decide.  An observation made by Mr. Sclater well illustrates
our ignorance of the laws which regulate the appearance and disappearance
of stripes; the species of Asinus which inhabit the Asiatic continent are
destitute of stripes, not having even the cross shoulder-stripe, whilst
those which inhabit Africa are conspicuously striped, with the partial
exception of A. taeniopus, which has only the cross shoulder-stripe and
generally some faint bars on the legs; and this species inhabits the almost
intermediate region of Upper Egypt and Abyssinia.  (44.  'Proc. Zool. Soc.'
1862, p. 164.  See, also, Dr. Hartmann, 'Ann. d. Landw.' Bd. xliii. s.
222.)

QUADRUMANA.

[Fig. 72.  Head of Semnopithecus rubicundus.  This and the following
figures (from Prof. Gervais) are given to shew the odd arrangement and
development of the hair on the head.

Fig. 73.  Head of Semnopithecus comatus.

Fig. 74.  Head of Cebus capucinus.

Fig. 75.  Head of Ateles marginatus.

Fig. 76.  Head of Cebus vellerosus.]

Before we conclude, it will be well to add a few remarks on the ornaments
of monkeys.  In most of the species the sexes resemble each other in
colour, but in some, as we have seen, the males differ from the females,
especially in the colour of the naked parts of the skin, in the development
of the beard, whiskers, and mane.  Many species are coloured either in so
extraordinary or so beautiful a manner, and are furnished with such curious
and elegant crests of hair, that we can hardly avoid looking at these
characters as having been gained for the sake of ornament.  The
accompanying figures (Figs. 72 to 76) serve to shew the arrangement of the
hair on the face and head in several species.  It is scarcely conceivable
that these crests of hair, and the strongly contrasted colours of the fur
and skin, can be the result of mere variability without the aid of
selection; and it is inconceivable that they can be of use in any ordinary
way to these animals.  If so, they have probably been gained through sexual
selection, though transmitted equally, or almost equally, to both sexes.
With many of the Quadrumana, we have additional evidence of the action of
sexual selection in the greater size and strength of the males, and in the
greater development of their canine teeth, in comparison with the females.

[Fig. 77.  Cercopithecus petaurista (from Brehm).]

A few instances will suffice of the strange manner in which both sexes of
some species are coloured, and of the beauty of others.  The face of the
Cercopithecus petaurista (Fig. 77) is black, the whiskers and beard being
white, with a defined, round, white spot on the nose, covered with short
white hair, which gives to the animal an almost ludicrous aspect.  The
Semnopithecus frontatus likewise has a blackish face with a long black
beard, and a large naked spot on the forehead of a bluish-white colour.
The face of Macacus lasiotus is dirty flesh-coloured, with a defined red
spot on each cheek.  The appearance of Cercocebus aethiops is grotesque,
with its black face, white whiskers and collar, chestnut head, and a large
naked white spot over each eyelid.  In very many species, the beard,
whiskers, and crests of hair round the face are of a different colour from
the rest of the head, and when different, are always of a lighter tint (45.
I observed this fact in the Zoological Gardens; and many cases may be seen
in the coloured plates in Geoffroy St.-Hilaire and F. Cuvier, 'Histoire
Nat. des Mammiferes,' tom. i. 1824.), being often pure white, sometimes
bright yellow, or reddish.  The whole face of the South American Brachyurus
calvus is of a "glowing scarlet hue"; but this colour does not appear until
the animal is nearly mature.  (46.  Bates, 'The Naturalist on the Amazons,'
1863, vol. ii. p. 310.)  The naked skin of the face differs wonderfully in
colour in the various species.  It is often brown or flesh-colour, with
parts perfectly white, and often as black as that of the most sooty negro.
In the Brachyurus the scarlet tint is brighter than that of the most
blushing Caucasian damsel.  It is sometimes more distinctly orange than in
any Mongolian, and in several species it is blue, passing into violet or
grey.  In all the species known to Mr. Bartlett, in which the adults of
both sexes have strongly-coloured faces, the colours are dull or absent
during early youth.  This likewise holds good with the mandrill and Rhesus,
in which the face and the posterior parts of the body are brilliantly
coloured in one sex alone.  In these latter cases we have reason to believe
that the colours were acquired through sexual selection; and we are
naturally led to extend the same view to the foregoing species, though both
sexes when adult have their faces coloured in the same manner.

[Fig. 78.  Cercopithecus diana (from Brehm).]

Although many kinds of monkeys are far from beautiful according to our
taste, other species are universally admired for their elegant appearance
and bright colours.  The Semnopithecus nemaeus, though peculiarly coloured,
is described as extremely pretty; the orange-tinted face is surrounded by
long whiskers of glossy whiteness, with a line of chestnut-red over the
eyebrows; the fur on the back is of a delicate grey, with a square patch on
the loins, the tail and the fore-arms being of a pure white; a gorget of
chestnut surmounts the chest; the thighs are black, with the legs chestnut-
red.  I will mention only two other monkeys for their beauty; and I have
selected these as presenting slight sexual differences in colour, which
renders it in some degree probable that both sexes owe their elegant
appearance to sexual selection.  In the moustache-monkey (Cercopithecus
cephus) the general colour of the fur is mottled-greenish with the throat
white; in the male the end of the tail is chestnut, but the face is the
most ornamented part, the skin being chiefly bluish-grey, shading into a
blackish tint beneath the eyes, with the upper lip of a delicate blue,
clothed on the lower edge with a thin black moustache; the whiskers are
orange-coloured, with the upper part black, forming a band which extends
backwards to the ears, the latter being clothed with whitish hairs.  In the
Zoological Society's Gardens I have often overheard visitors admiring the
beauty of another monkey, deservedly called Cercopithecus diana (Fig. 78);
the general colour of the fur is grey; the chest and inner surface of the
forelegs are white; a large triangular defined space on the hinder part of
the back is rich chestnut; in the male the inner sides of the thighs and
the abdomen are delicate fawn-coloured, and the top of the head is black;
the face and ears are intensely black, contrasting finely with a white
transverse crest over the eyebrows and a long white peaked beard, of which
the basal portion is black.  (47.  I have seen most of the above monkeys in
the Zoological Society's Gardens.  The description of the Semnopithecus
nemaeus is taken from Mr. W.C. Martin's 'Natural History of Mammalia,'
1841, p. 460; see also pp. 475, 523.)

In these and many other monkeys, the beauty and singular arrangement of
their colours, and still more the diversified and elegant arrangement of
the crests and tufts of hair on their heads, force the conviction on my
mind that these characters have been acquired through sexual selection
exclusively as ornaments.

SUMMARY.

The law of battle for the possession of the female appears to prevail
throughout the whole great class of mammals.  Most naturalists will admit
that the greater size, strength, courage, and pugnacity of the male, his
special weapons of offence, as well as his special means of defence, have
been acquired or modified through that form of selection which I have
called sexual.  This does not depend on any superiority in the general
struggle for life, but on certain individuals of one sex, generally the
male, being successful in conquering other males, and leaving a larger
number of offspring to inherit their superiority than do the less
successful males.

There is another and more peaceful kind of contest, in which the males
endeavour to excite or allure the females by various charms.  This is
probably carried on in some cases by the powerful odours emitted by the
males during the breeding-season; the odoriferous glands having been
acquired through sexual selection.  Whether the same view can be extended
to the voice is doubtful, for the vocal organs of the males must have been
strengthened by use during maturity, under the powerful excitements of
love, jealousy or rage, and will consequently have been transmitted to the
same sex.  Various crests, tufts, and mantles of hair, which are either
confined to the male, or are more developed in this sex than in the female,
seem in most cases to be merely ornamental, though they sometimes serve as
a defence against rival males.  There is even reason to suspect that the
branching horns of stags, and the elegant horns of certain antelopes,
though properly serving as weapons of offence or defence, have been partly
modified for ornament.

When the male differs in colour from the female, he generally exhibits
darker and more strongly-contrasted tints.  We do not in this class meet
with the splendid red, blue, yellow, and green tints, so common with male
birds and many other animals.  The naked parts, however, of certain
Quadrumana must be excepted; for such parts, often oddly situated, are
brilliantly coloured in some species.  The colours of the male in other
cases may be due to simple variation, without the aid of selection.  But
when the colours are diversified and strongly pronounced, when they are not
developed until near maturity, and when they are lost after emasculation,
we can hardly avoid the conclusion that they have been acquired through
sexual selection for the sake of ornament, and have been transmitted
exclusively, or almost exclusively, to the same sex.  When both sexes are
coloured in the same manner, and the colours are conspicuous or curiously
arranged, without being of the least apparent use as a protection, and
especially when they are associated with various other ornamental
appendages, we are led by analogy to the same conclusion, namely, that they
have been acquired through sexual selection, although transmitted to both
sexes.  That conspicuous and diversified colours, whether confined to the
males or common to both sexes, are as a general rule associated in the same
groups and sub-groups with other secondary sexual characters serving for
war or for ornament, will be found to hold good, if we look back to the
various cases given in this and the last chapter.

The law of the equal transmission of characters to both sexes, as far as
colour and other ornaments are concerned, has prevailed far more
extensively with mammals than with birds; but weapons, such as horns and
tusks, have often been transmitted either exclusively or much more
perfectly to the males than to the females.  This is surprising, for, as
the males generally use their weapons for defence against enemies of all
kinds, their weapons would have been of service to the females.  As far as
we can see, their absence in this sex can be accounted for only by the form
of inheritance which has prevailed.  Finally, with quadrupeds the contest
between the individuals of the same sex, whether peaceful or bloody, has,
with the rarest exceptions, been confined to the males; so that the latter
have been modified through sexual selection, far more commonly than the
females, either for fighting with each other or for alluring the opposite
sex.


PART III.

SEXUAL SELECTION IN RELATION TO MAN, AND CONCLUSION.


CHAPTER XIX.

SECONDARY SEXUAL CHARACTERS OF MAN.

Differences between man and woman--Causes of such differences and of
certain characters common to both sexes--Law of battle--Differences in
mental powers, and voice--On the influence of beauty in determining the
marriages of mankind--Attention paid by savages to ornaments--Their ideas
of beauty in woman--The tendency to exaggerate each natural peculiarity.

With mankind the differences between the sexes are greater than in most of
the Quadrumana, but not so great as in some, for instance, the mandrill.
Man on an average is considerably taller, heavier, and stronger than woman,
with squarer shoulders and more plainly-pronounced muscles.  Owing to the
relation which exists between muscular development and the projection of
the brows (1.  Schaaffhausen, translation in 'Anthropological Review,' Oct.
1868, pp. 419, 420, 427.), the superciliary ridge is generally more marked
in man than in woman.  His body, and especially his face, is more hairy,
and his voice has a different and more powerful tone.  In certain races the
women are said to differ slightly in tint from the men.  For instance,
Schweinfurth, in speaking of a negress belonging to the Monbuttoos, who
inhabit the interior of Africa a few degrees north of the equator, says,
"Like all her race, she had a skin several shades lighter than her
husband's, being something of the colour of half-roasted coffee." (2.  'The
Heart of Africa,' English transl. 1873, vol i. p. 544.)  As the women
labour in the fields and are quite unclothed, it is not likely that they
differ in colour from the men owing to less exposure to the weather.
European women are perhaps the brighter coloured of the two sexes, as may
be seen when both have been equally exposed.

Man is more courageous, pugnacious and energetic than woman, and has a more
inventive genius.  His brain is absolutely larger, but whether or not
proportionately to his larger body, has not, I believe, been fully
ascertained.  In woman the face is rounder; the jaws and the base of the
skull smaller; the outlines of the body rounder, in parts more prominent;
and her pelvis is broader than in man (3.  Ecker, translation, in
'Anthropological Review,' Oct. 1868, pp. 351-356.  The comparison of the
form of the skull in men and women has been followed out with much care by
Welcker.); but this latter character may perhaps be considered rather as a
primary than a secondary sexual character.  She comes to maturity at an
earlier age than man.

As with animals of all classes, so with man, the distinctive characters of
the male sex are not fully developed until he is nearly mature; and if
emasculated they never appear.  The beard, for instance, is a secondary

sexual character, and male children are beardless, though at an early age
they have abundant hair on the head.  It is probably due to the rather late
appearance in life of the successive variations whereby man has acquired
his masculine characters, that they are transmitted to the male sex alone.
Male and female children resemble each other closely, like the young of so
many other animals in which the adult sexes differ widely; they likewise
resemble the mature female much more closely than the mature male.  The
female, however, ultimately assumes certain distinctive characters, and in
the formation of her skull, is said to be intermediate between the child
and the man.  (4.  Ecker and Welcker, ibid. pp. 352, 355; Vogt, 'Lectures
on Man,' Eng. translat. p. 81.)  Again, as the young of closely allied
though distinct species do not differ nearly so much from each other as do
the adults, so it is with the children of the different races of man.  Some
have even maintained that race-differences cannot be detected in the
infantile skull.  (5.  Schaaffhausen, 'Anthropolog. Review,' ibid. p. 429.)
In regard to colour, the new-born negro child is reddish nut-brown, which
soon becomes slaty-grey; the black colour being fully developed within a
year in the Soudan, but not until three years in Egypt.  The eyes of the
negro are at first blue, and the hair chestnut-brown rather than black,
being curled only at the ends.  The children of the Australians immediately
after birth are yellowish-brown, and become dark at a later age.  Those of
the Guaranys of Paraguay are whitish-yellow, but they acquire in the course
of a few weeks the yellowish-brown tint of their parents.  Similar
observations have been made in other parts of America.  (6.  Pruner-Bey, on
negro infants as quoted by Vogt, 'Lectures on Man,' Eng. translat. 1864, p.
189:  for further facts on negro infants, as quoted from Winterbottom and
Camper, see Lawrence, 'Lectures on Physiology,' etc. 1822, p. 451.  For the
infants of the Guaranys, see Rengger, 'Saeugethiere,' etc. s. 3.  See also
Godron, 'De l'Espece,' tom. ii. 1859, p. 253.  For the Australians, Waitz,
'Introduction to Anthropology,' Eng. translat. 1863, p. 99.)

I have specified the foregoing differences between the male and female sex
in mankind, because they are curiously like those of the Quadrumana.  With
these animals the female is mature at an earlier age than the male; at
least this is certainly the case in Cebus azarae.  (7.  Rengger,
'Saeugethiere,' etc., 1830, s. 49.)  The males of most species are larger
and stronger than the females, of which fact the gorilla affords a well-
known instance.  Even in so trifling a character as the greater prominence
of the superciliary ridge, the males of certain monkeys differ from the
females (8.  As in Macacus cynomolgus (Desmarest, 'Mammalogie,' p. 65), and
in Hylobates agilis (Geoffroy St.-Hilaire and F. Cuvier, 'Histoire Nat. des
Mammiferes,' 1824, tom. i. p. 2).), and agree in this respect with mankind.
In the gorilla and certain other monkeys, the cranium of the adult male
presents a strongly-marked sagittal crest, which is absent in the female;
and Ecker found a trace of a similar difference between the two sexes in
the Australians.  (9.  'Anthropological Review,' Oct. 1868, p. 353.)  With
monkeys when there is any difference in the voice, that of the male is the
more powerful.  We have seen that certain male monkeys have a well-
developed beard, which is quite deficient, or much less developed in the
female.  No instance is known of the beard, whiskers, or moustache being
larger in the female than in the male monkey.  Even in the colour of the
beard there is a curious parallelism between man and the Quadrumana, for
with man when the beard differs in colour from the hair of the head, as is
commonly the case, it is, I believe, almost always of a lighter tint, being
often reddish.  I have repeatedly observed this fact in England; but two
gentlemen have lately written to me, saying that they form an exception to
the rule.  One of these gentlemen accounts for the fact by the wide
difference in colour of the hair on the paternal and maternal sides of his
family.  Both had been long aware of this peculiarity (one of them having
often been accused of dyeing his beard), and had been thus led to observe
other men, and were convinced that the exceptions were very rare.  Dr.
Hooker attended to this little point for me in Russia, and found no
exception to the rule.  In Calcutta, Mr. J. Scott, of the Botanic Gardens,
was so kind as to observe the many races of men to be seen there, as well
as in some other parts of India, namely, two races of Sikhim, the Bhoteas,
Hindoos, Burmese, and Chinese, most of which races have very little hair on
the face; and he always found that when there was any difference in colour
between the hair of the head and the beard, the latter was invariably
lighter.  Now with monkeys, as has already been stated, the beard
frequently differs strikingly in colour from the hair of the head, and in
such cases it is always of a lighter hue, being often pure white, sometimes
yellow or reddish.  (10.  Mr. Blyth informs me that he has only seen one
instance of the beard, whiskers, etc., in a monkey becoming white with old
age, as is so commonly the case with us.  This, however, occurred in an
aged Macacus cynomolgus, kept in confinement whose moustaches were
"remarkably long and human-like."  Altogether this old monkey presented a
ludicrous resemblance to one of the reigning monarchs of Europe, after whom
he was universally nick-named.  In certain races of man the hair on the
head hardly ever becomes grey; thus Mr. D. Forbes has never, as he informs
me, seen an instance with the Aymaras and Quichuas of South America.)

In regard to the general hairiness of the body, the women in all races are
less hairy than the men; and in some few Quadrumana the under side of the
body of the female is less hairy than that of the male.  (11.  This is the
case with the females of several species of Hylobates; see Geoffroy St.-
Hilaire and F. Cuvier, 'Hist. Nat. des Mamm.' tom. i.  See also, on H. lar,
'Penny Cyclopedia,' vol. ii. pp. 149, 150.)  Lastly, male monkeys, like
men, are bolder and fiercer than the females.  They lead the troop, and
when there is danger, come to the front.  We thus see how close is the
parallelism between the sexual differences of man and the Quadrumana.  With
some few species, however, as with certain baboons, the orang and the
gorilla, there is a considerably greater difference between the sexes, as
in the size of the canine teeth, in the development and colour of the hair,
and especially in the colour of the naked parts of the skin, than in
mankind.

All the secondary sexual characters of man are highly variable, even within
the limits of the same race; and they differ much in the several races.
These two rules hold good generally throughout the animal kingdom.  In the
excellent observations made on board the Novara (12.  The results were
deduced by Dr. Weisbach from the measurements made by Drs. K. Scherzer and
Schwarz, see 'Reise der Novara:  Anthropolog. Theil,' 1867, ss. 216, 231,
234, 236, 239, 269.), the male Australians were found to exceed the females
by only 65 millim. in height, whilst with the Javans the average excess was
218 millim.; so that in this latter race the difference in height between
the sexes is more than thrice as great as with the Australians.  Numerous
measurements were carefully made of the stature, the circumference of the
neck and chest, the length of the back-bone and of the arms, in various
races; and nearly all these measurements shew that the males differ much
more from one another than do the females.  This fact indicates that, as
far as these characters are concerned, it is the male which has been
chiefly modified, since the several races diverged from their common stock.

The development of the beard and the hairiness of the body differ
remarkably in the men of distinct races, and even in different tribes or
families of the same race.  We Europeans see this amongst ourselves.  In
the Island of St. Kilda, according to Martin (13.  'Voyage to St. Kilda'
(3rd ed. 1753), p. 37.), the men do not acquire beards until the age of
thirty or upwards, and even then the beards are very thin.  On the
Europaeo-Asiatic continent, beards prevail until we pass beyond India;
though with the natives of Ceylon they are often absent, as was noticed in
ancient times by Diodorus.  (14.  Sir J.E. Tennent, 'Ceylon,' vol. ii.
1859, p. 107.)  Eastward of India beards disappear, as with the Siamese,
Malays, Kalmucks, Chinese, and Japanese; nevertheless, the Ainos (15.
Quatrefages, 'Revue des Cours Scientifiques,' Aug. 29, 1868, p. 630; Vogt,
'Lectures on Man,' Eng. trans. p. 127.), who inhabit the northernmost
islands of the Japan Archipelago, are the hairiest men in the world.  With
negroes the beard is scanty or wanting, and they rarely have whiskers; in
both sexes the body is frequently almost destitute of fine down.  (16.  On
the beards of negroes, Vogt, 'Lectures,' etc. p. 127; Waitz, 'Introduct. to
Anthropology,' Engl. translat. 1863, vol. i. p. 96.  It is remarkable that
in the United States ('Investigations in Military and Anthropological
Statistics of American Soldiers,' 1869, p. 569) the pure negroes and their
crossed offspring seem to have bodies almost as hairy as Europeans.)  On
the other hand, the Papuans of the Malay Archipelago, who are nearly as
black as negroes, possess well-developed beards.  (17.  Wallace, 'The Malay
Arch.' vol. ii. 1869, p. 178.)  In the Pacific Ocean the inhabitants of the
Fiji Archipelago have large bushy beards, whilst those of the not distant
archipelagoes of Tonga and Samoa are beardless; but these men belong to
distinct races.  In the Ellice group all the inhabitants belong to the same
race; yet on one island alone, namely Nunemaya, "the men have splendid
beards"; whilst on the other islands "they have, as a rule, a dozen
straggling hairs for a beard."  (18.  Dr. J. Barnard Davis on Oceanic
Races, in 'Anthropological Review,' April 1870, pp. 185, 191.)

Throughout the great American continent the men may be said to be
beardless; but in almost all the tribes a few short hairs are apt to appear
on the face, especially in old age.  With the tribes of North America,
Catlin estimates that eighteen out of twenty men are completely destitute
by nature of a beard; but occasionally there may be seen a man, who has
neglected to pluck out the hairs at puberty, with a soft beard an inch or
two in length.  The Guaranys of Paraguay differ from all the surrounding
tribes in having a small beard, and even some hair on the body, but no
whiskers.  (19.  Catlin, 'North American Indians,' 3rd. ed. 1842, vol. ii.
p. 227.  On the Guaranys, see Azara, 'Voyages dans l'Amerique Merid.' tom.
ii. 1809, p. 85; also Rengger, 'Saeugethiere von Paraguay,' s. 3.)  I am
informed by Mr. D. Forbes, who particularly attended to this point, that
the Aymaras and Quichuas of the Cordillera are remarkably hairless, yet in
old age a few straggling hairs occasionally appear on the chin.  The men of
these two tribes have very little hair on the various parts of the body
where hair grows abundantly in Europeans, and the women have none on the
corresponding parts.  The hair on the head, however, attains an
extraordinary length in both sexes, often reaching almost to the ground;
and this is likewise the case with some of the N. American tribes.  In the
amount of hair, and in the general shape of the body, the sexes of the
American aborigines do not differ so much from each other, as in most other
races.  (20.  Prof. and Mrs. Agassiz ('Journey in Brazil,' p. 530) remark
that the sexes of the American Indians differ less than those of the
negroes and of the higher races.  See also Rengger, ibid. p. 3, on the
Guaranys.)  This fact is analogous with what occurs with some closely
allied monkeys; thus the sexes of the chimpanzee are not as different as
those of the orang or gorilla.  (21.  Rutimeyer, 'Die Grenzen der
Thierwelt; eine Betrachtung zu Darwin's Lehre,' 1868, s. 54.)

In the previous chapters we have seen that with mammals, birds, fishes,
insects, etc., many characters, which there is every reason to believe were
primarily gained through sexual selection by one sex, have been transferred
to the other.  As this same form of transmission has apparently prevailed
much with mankind, it will save useless repetition if we discuss the origin
of characters peculiar to the male sex together with certain other
characters common to both sexes.

LAW OF BATTLE.

With savages, for instance, the Australians, the women are the constant
cause of war both between members of the same tribe and between distinct
tribes.  So no doubt it was in ancient times; "nam fuit ante Helenam mulier
teterrima belli causa."  With some of the North American Indians, the
contest is reduced to a system.  That excellent observer, Hearne (22.  'A
Journey from Prince of Wales Fort,' 8vo. ed. Dublin, 1796, p. 104.  Sir J.
Lubbock ('Origin of Civilisation,' 1870, p. 69) gives other and similar
cases in North America.  For the Guanas of South America see Azara,
'Voyages,' etc. tom. ii. p. 94.), says:--"It has ever been the custom among
these people for the men to wrestle for any woman to whom they are
attached; and, of course, the strongest party always carries off the prize.
A weak man, unless he be a good hunter, and well-beloved, is seldom
permitted to keep a wife that a stronger man thinks worth his notice.  This
custom prevails throughout all the tribes, and causes a great spirit of
emulation among their youth, who are upon all occasions, from their
childhood, trying their strength and skill in wrestling."  With the Guanas
of South America, Azara states that the men rarely marry till twenty years
old or more, as before that age they cannot conquer their rivals.

Other similar facts could be given; but even if we had no evidence on this
head, we might feel almost sure, from the analogy of the higher Quadrumana
(23.  On the fighting of the male gorillas, see Dr. Savage, in 'Boston
Journal of Natural History,' vol. v. 1847, p. 423.  On Presbytis entellus,
see the 'Indian Field,' 1859, p. 146.), that the law of battle had
prevailed with man during the early stages of his development.  The
occasional appearance at the present day of canine teeth which project
above the others, with traces of a diastema or open space for the reception
of the opposite canines, is in all probability a case of reversion to a
former state, when the progenitors of man were provided with these weapons,
like so many existing male Quadrumana.  It was remarked in a former chapter
that as man gradually became erect, and continually used his hands and arms
for fighting with sticks and stones, as well as for the other purposes of
life, he would have used his jaws and teeth less and less.  The jaws,
together with their muscles, would then have been reduced through disuse,
as would the teeth through the not well understood principles of
correlation and economy of growth; for we everywhere see that parts, which
are no longer of service, are reduced in size.  By such steps the original
inequality between the jaws and teeth in the two sexes of mankind would
ultimately have been obliterated.  The case is almost parallel with that of
many male Ruminants, in which the canine teeth have been reduced to mere
rudiments, or have disappeared, apparently in consequence of the
development of horns.  As the prodigious difference between the skulls of
the two sexes in the orang and gorilla stands in close relation with the
development of the immense canine teeth in the males, we may infer that the
reduction of the jaws and teeth in the early male progenitors of man must
have led to a most striking and favourable change in his appearance.

There can be little doubt that the greater size and strength of man, in
comparison with woman, together with his broader shoulders, more developed
muscles, rugged outline of body, his greater courage and pugnacity, are all
due in chief part to inheritance from his half-human male ancestors.  These
characters would, however, have been preserved or even augmented during the
long ages of man's savagery, by the success of the strongest and boldest
men, both in the general struggle for life and in their contests for wives;
a success which would have ensured their leaving a more numerous progeny
than their less favoured brethren.  It is not probable that the greater
strength of man was primarily acquired through the inherited effects of his
having worked harder than woman for his own subsistence and that of his
family; for the women in all barbarous nations are compelled to work at
least as hard as the men.  With civilised people the arbitrament of battle
for the possession of the women has long ceased; on the other hand, the
men, as a general rule, have to work harder than the women for their joint
subsistence, and thus their greater strength will have been kept up.

DIFFERENCE IN THE MENTAL POWERS OF THE TWO SEXES.

With respect to differences of this nature between man and woman, it is
probable that sexual selection has played a highly important part.  I am
aware that some writers doubt whether there is any such inherent
difference; but this is at least probable from the analogy of the lower
animals which present other secondary sexual characters.  No one disputes
that the bull differs in disposition from the cow, the wild-boar from the
sow, the stallion from the mare, and, as is well known to the keepers of
menageries, the males of the larger apes from the females.  Woman seems to
differ from man in mental disposition, chiefly in her greater tenderness
and less selfishness; and this holds good even with savages, as shewn by a
well-known passage in Mungo Park's Travels, and by statements made by many
other travellers.  Woman, owing to her maternal instincts, displays these
qualities towards her infants in an eminent degree; therefore it is likely
that she would often extend them towards her fellow-creatures.  Man is the
rival of other men; he delights in competition, and this leads to ambition
which passes too easily into selfishness.  These latter qualities seem to
be his natural and unfortunate birthright.  It is generally admitted that
with woman the powers of intuition, of rapid perception, and perhaps of
imitation, are more strongly marked than in man; but some, at least, of
these faculties are characteristic of the lower races, and therefore of a
past and lower state of civilisation.

The chief distinction in the intellectual powers of the two sexes is shewn
by man's attaining to a higher eminence, in whatever he takes up, than can
woman--whether requiring deep thought, reason, or imagination, or merely
the use of the senses and hands.  If two lists were made of the most
eminent men and women in poetry, painting, sculpture, music (inclusive both
of composition and performance), history, science, and philosophy, with
half-a-dozen names under each subject, the two lists would not bear
comparison.  We may also infer, from the law of the deviation from
averages, so well illustrated by Mr. Galton, in his work on 'Hereditary
Genius,' that if men are capable of a decided pre-eminence over women in
many subjects, the average of mental power in man must be above that of
woman.

Amongst the half-human progenitors of man, and amongst savages, there have
been struggles between the males during many generations for the possession
of the females.  But mere bodily strength and size would do little for
victory, unless associated with courage, perseverance, and determined
energy.  With social animals, the young males have to pass through many a
contest before they win a female, and the older males have to retain their
females by renewed battles.  They have, also, in the case of mankind, to
defend their females, as well as their young, from enemies of all kinds,
and to hunt for their joint subsistence.  But to avoid enemies or to attack
them with success, to capture wild animals, and to fashion weapons,
requires the aid of the higher mental faculties, namely, observation,
reason, invention, or imagination.  These various faculties will thus have
been continually put to the test and selected during manhood; they will,
moreover, have been strengthened by use during this same period of life.
Consequently in accordance with the principle often alluded to, we might
expect that they would at least tend to be transmitted chiefly to the male
offspring at the corresponding period of manhood.

Now, when two men are put into competition, or a man with a woman, both
possessed of every mental quality in equal perfection, save that one has
higher energy, perseverance, and courage, the latter will generally become
more eminent in every pursuit, and will gain the ascendancy.  (24.  J.
Stuart Mill remarks ('The Subjection of Women,' 1869, p. 122), "The things
in which man most excels woman are those which require most plodding, and
long hammering at single thoughts."  What is this but energy and
perseverance?)  He may be said to possess genius--for genius has been
declared by a great authority to be patience; and patience, in this sense,
means unflinching, undaunted perseverance.  But this view of genius is
perhaps deficient; for without the higher powers of the imagination and
reason, no eminent success can be gained in many subjects.  These latter
faculties, as well as the former, will have been developed in man, partly
through sexual selection,--that is, through the contest of rival males, and
partly through natural selection, that is, from success in the general
struggle for life; and as in both cases the struggle will have been during
maturity, the characters gained will have been transmitted more fully to
the male than to the female offspring.  It accords in a striking manner
with this view of the modification and re-inforcement of many of our mental
faculties by sexual selection, that, firstly, they notoriously undergo a
considerable change at puberty (25.  Maudsley, 'Mind and Body,' p. 31.),
and, secondly, that eunuchs remain throughout life inferior in these same
qualities.  Thus, man has ultimately become superior to woman.  It is,
indeed, fortunate that the law of the equal transmission of characters to
both sexes prevails with mammals; otherwise, it is probable that man would
have become as superior in mental endowment to woman, as the peacock is in
ornamental plumage to the peahen.

It must be borne in mind that the tendency in characters acquired by either
sex late in life, to be transmitted to the same sex at the same age, and of
early acquired characters to be transmitted to both sexes, are rules which,
though general, do not always hold.  If they always held good, we might
conclude (but I here exceed my proper bounds) that the inherited effects of
the early education of boys and girls would be transmitted equally to both
sexes; so that the present inequality in mental power between the sexes
would not be effaced by a similar course of early training; nor can it have
been caused by their dissimilar early training.  In order that woman should
reach the same standard as man, she ought, when nearly adult, to be trained
to energy and perseverance, and to have her reason and imagination
exercised to the highest point; and then she would probably transmit these
qualities chiefly to her adult daughters.  All women, however, could not be
thus raised, unless during many generations those who excelled in the above
robust virtues were married, and produced offspring in larger numbers than
other women.  As before remarked of bodily strength, although men do not
now fight for their wives, and this form of selection has passed away, yet
during manhood, they generally undergo a severe struggle in order to
maintain themselves and their families; and this will tend to keep up or
even increase their mental powers, and, as a consequence, the present
inequality between the sexes.  (26.  An observation by Vogt bears on this
subject:  he says, "It is a remarkable circumstance, that the difference
between the sexes, as regards the cranial cavity, increases with the
development of the race, so that the male European excels much more the
female, than the negro the negress.  Welcker confirms this statement of
Huschke from his measurements of negro and German skulls."  But Vogt admits
('Lectures on Man,' Eng. translat. 1864, p. 81) that more observations are
requisite on this point.

VOICE AND MUSICAL POWERS.

In some species of Quadrumana there is a great difference between the adult
sexes, in the power of their voices and in the development of the vocal
organs; and man appears to have inherited this difference from his early
progenitors.  His vocal cords are about one-third longer than in woman, or
than in boys; and emasculation produces the same effect on him as on the
lower animals, for it "arrests that prominent growth of the thyroid, etc.,
which accompanies the elongation of the cords."  (27.  Owen, 'Anatomy of
Vertebrates,' vol. iii. p. 603.)  With respect to the cause of this
difference between the sexes, I have nothing to add to the remarks in the
last chapter on the probable effects of the long-continued use of the vocal
organs by the male under the excitement of love, rage and jealousy.
According to Sir Duncan Gibb (28.  'Journal of the Anthropological
Society,' April 1869, p. lvii. and lxvi.), the voice and the form of the
larynx differ in the different races of mankind; but with the Tartars,
Chinese, etc., the voice of the male is said not to differ so much from
that of the female, as in most other races.

The capacity and love for singing or music, though not a sexual character
in man, must not here be passed over.  Although the sounds emitted by
animals of all kinds serve many purposes, a strong case can be made out,
that the vocal organs were primarily used and perfected in relation to the
propagation of the species.  Insects and some few spiders are the lowest
animals which voluntarily produce any sound; and this is generally effected
by the aid of beautifully constructed stridulating organs, which are often
confined to the males.  The sounds thus produced consist, I believe in all
cases, of the same note, repeated rhythmically (29.  Dr. Scudder, 'Notes on
Stridulation,' in 'Proc. Boston Soc. of Nat. Hist.' vol. xi. April 1868.);
and this is sometimes pleasing even to the ears of man.  The chief and, in
some cases, exclusive purpose appears to be either to call or charm the
opposite sex.

The sounds produced by fishes are said in some cases to be made only by the
males during the breeding-season.  All the air-breathing Vertebrata
necessarily possess an apparatus for inhaling and expelling air, with a
pipe capable of being closed at one end.  Hence when the primeval members
of this class were strongly excited and their muscles violently contracted,
purposeless sounds would almost certainly have been produced; and these, if
they proved in any way serviceable, might readily have been modified or
intensified by the preservation of properly adapted variations.  The lowest
Vertebrates which breathe air are Amphibians; and of these, frogs and toads
possess vocal organs, which are incessantly used during the breeding-
season, and which are often more highly developed in the male than in the
female.  The male alone of the tortoise utters a noise, and this only
during the season of love.  Male alligators roar or bellow during the same
season.  Every one knows how much birds use their vocal organs as a means
of courtship; and some species likewise perform what may be called
instrumental music.

In the class of Mammals, with which we are here more particularly
concerned, the males of almost all the species use their voices during the
breeding-season much more than at any other time; and some are absolutely
mute excepting at this season.  With other species both sexes, or only the
females, use their voices as a love-call.  Considering these facts, and
that the vocal organs of some quadrupeds are much more largely developed in
the male than in the female, either permanently or temporarily during the
breeding-season; and considering that in most of the lower classes the
sounds produced by the males, serve not only to call but to excite or
allure the female, it is a surprising fact that we have not as yet any good
evidence that these organs are used by male mammals to charm the females.
The American Mycetes caraya perhaps forms an exception, as does the
Hylobates agilis, an ape allied to man.  This gibbon has an extremely loud
but musical voice.  Mr. Waterhouse states (30.  Given in W.C.L. Martin's
'General Introduction to Natural History of Mamm. Animals,' 1841, p. 432;
Owen, 'Anatomy of Vertebrates,' vol. iii, p. 600.), "It appeared to me that
in ascending and descending the scale, the intervals were always exactly
half-tones; and I am sure that the highest note was the exact octave to the
lowest.  The quality of the notes is very musical; and I do not doubt that
a good violinist would be able to give a correct idea of the gibbon's
composition, excepting as regards its loudness."  Mr. Waterhouse then gives
the notes.  Professor Owen, who is a musician, confirms the foregoing
statement, and remarks, though erroneously, that this gibbon "alone of
brute mammals may be said to sing."  It appears to be much excited after
its performance.  Unfortunately, its habits have never been closely
observed in a state of nature; but from the analogy of other animals, it is
probable that it uses its musical powers more especially during the season
of courtship.

This gibbon is not the only species in the genus which sings, for my son,
Francis Darwin, attentively listened in the Zoological Gardens to H.
leuciscus whilst singing a cadence of three notes, in true musical
intervals and with a clear musical tone.  It is a more surprising fact that
certain rodents utter musical sounds.  Singing mice have often been
mentioned and exhibited, but imposture has commonly been suspected.  We
have, however, at last a clear account by a well-known observer, the Rev.
S. Lockwood (31.  The 'American Naturalist,' 1871, p. 761.), of the musical
powers of an American species, the Hesperomys cognatus, belonging to a
genus distinct from that of the English mouse.  This little animal was kept
in confinement, and the performance was repeatedly heard.  In one of the
two chief songs, "the last bar would frequently be prolonged to two or
three; and she would sometimes change from C sharp and D, to C natural and
D, then warble on these two notes awhile, and wind up with a quick chirp on
C sharp and D.  The distinctness between the semitones was very marked, and
easily appreciable to a good ear."  Mr. Lockwood gives both songs in
musical notation; and adds that though this little mouse "had no ear for
time, yet she would keep to the key of B (two flats) and strictly in a
major key."..."Her soft clear voice falls an octave with all the precision
possible; then at the wind up, it rises again into a very quick trill on C
sharp and D."

A critic has asked how the ears of man, and he ought to have added of other
animals, could have been adapted by selection so as to distinguish musical
notes.  But this question shews some confusion on the subject; a noise is
the sensation resulting from the co-existence of several aerial "simple
vibrations" of various periods, each of which intermits so frequently that
its separate existence cannot be perceived.  It is only in the want of
continuity of such vibrations, and in their want of harmony inter se, that
a noise differs from a musical note.  Thus an ear to be capable of
discriminating noises--and the high importance of this power to all animals
is admitted by every one--must be sensitive to musical notes.  We have
evidence of this capacity even low down in the animal scale:  thus
Crustaceans are provided with auditory hairs of different lengths, which
have been seen to vibrate when the proper musical notes are struck.  (32.
Helmholtz, 'Theorie Phys. de la Musique,' 1868, p. 187.)  As stated in a
previous chapter, similar observations have been made on the hairs of the
antennae of gnats.  It has been positively asserted by good observers that
spiders are attracted by music.  It is also well known that some dogs howl
when hearing particular tones.  (33.  Several accounts have been published
to this effect.  Mr. Peach writes to me that an old dog of his howls when B
flat is sounded on the flute, and to no other note.  I may add another
instance of a dog always whining, when one note on a concertina, which was
out of tune, was played.)  Seals apparently appreciate music, and their
fondness for it "was well known to the ancients, and is often taken
advantage of by the hunters at the present day."  (34.  Mr. R. Brown, in
'Proc. Zool. Soc.' 1868, p. 410.)

Therefore, as far as the mere perception of musical notes is concerned,
there seems no special difficulty in the case of man or of any other
animal.  Helmholtz has explained on physiological principles why concords
are agreeable, and discords disagreeable to the human ear; but we are
little concerned with these, as music in harmony is a late invention.  We
are more concerned with melody, and here again, according to Helmholtz, it
is intelligible why the notes of our musical scale are used.  The ear
analyses all sounds into their component "simple vibrations," although we
are not conscious of this analysis.  In a musical note the lowest in pitch
of these is generally predominant, and the others which are less marked are
the octave, the twelfth, the second octave, etc., all harmonies of the
fundamental predominant note; any two notes of our scale have many of these
harmonic over-tones in common.  It seems pretty clear then, that if an
animal always wished to sing precisely the same song, he would guide
himself by sounding those notes in succession, which possess many over-
tones in common--that is, he would choose for his song, notes which belong
to our musical scale.

But if it be further asked why musical tones in a certain order and rhythm
give man and other animals pleasure, we can no more give the reason than
for the pleasantness of certain tastes and smells.  That they do give
pleasure of some kind to animals, we may infer from their being produced
during the season of courtship by many insects, spiders, fishes,
amphibians, and birds; for unless the females were able to appreciate such
sounds and were excited or charmed by them, the persevering efforts of the
males, and the complex structures often possessed by them alone, would be
useless; and this it is impossible to believe.

Human song is generally admitted to be the basis or origin of instrumental
music.  As neither the enjoyment nor the capacity of producing musical
notes are faculties of the least use to man in reference to his daily
habits of life, they must be ranked amongst the most mysterious with which
he is endowed.  They are present, though in a very rude condition, in men
of all races, even the most savage; but so different is the taste of the
several races, that our music gives no pleasure to savages, and their music
is to us in most cases hideous and unmeaning.  Dr. Seemann, in some
interesting remarks on this subject (35.  'Journal of Anthropological
Society,' Oct. 1870, p. clv.  See also the several later chapters in Sir
John Lubbock's 'Prehistoric Times,' 2nd ed. 1869, which contain an
admirable account of the habits of savages.), "doubts whether even amongst
the nations of Western Europe, intimately connected as they are by close
and frequent intercourse, the music of the one is interpreted in the same
sense by the others.  By travelling eastwards we find that there is
certainly a different language of music.  Songs of joy and dance-
accompaniments are no longer, as with us, in the major keys, but always in
the minor."  Whether or not the half-human progenitors of man possessed,
like the singing gibbons, the capacity of producing, and therefore no doubt
of appreciating, musical notes, we know that man possessed these faculties
at a very remote period.  M. Lartet has described two flutes made out of
the bones and horns of the reindeer, found in caves together with flint
tools and the remains of extinct animals.  The arts of singing and of
dancing are also very ancient, and are now practised by all or nearly all
the lowest races of man.  Poetry, which may be considered as the offspring
of song, is likewise so ancient, that many persons have felt astonished
that it should have arisen during the earliest ages of which we have any
record.

We see that the musical faculties, which are not wholly deficient in any
race, are capable of prompt and high development, for Hottentots and
Negroes have become excellent musicians, although in their native countries
they rarely practise anything that we should consider music.  Schweinfurth,
however, was pleased with some of the simple melodies which he heard in the
interior of Africa.  But there is nothing anomalous in the musical
faculties lying dormant in man:  some species of birds which never
naturally sing, can without much difficulty be taught to do so; thus a
house-sparrow has learnt the song of a linnet.  As these two species are
closely allied, and belong to the order of Insessores, which includes
nearly all the singing-birds in the world, it is possible that a progenitor
of the sparrow may have been a songster.  It is more remarkable that
parrots, belonging to a group distinct from the Insessores, and having
differently constructed vocal organs, can be taught not only to speak, but
to pipe or whistle tunes invented by man, so that they must have some
musical capacity.  Nevertheless it would be very rash to assume that
parrots are descended from some ancient form which was a songster.  Many
cases could be advanced of organs and instincts originally adapted for one
purpose, having been utilised for some distinct purpose.  (36.  Since this
chapter was printed, I have seen a valuable article by Mr. Chauncey Wright
('North American Review,' Oct. 1870, page 293), who, in discussing the
above subject, remarks, "There are many consequences of the ultimate laws
or uniformities of nature, through which the acquisition of one useful
power will bring with it many resulting advantages as well as limiting
disadvantages, actual or possible, which the principle of utility may not
have comprehended in its action."  As I have attempted to shew in an early
chapter of this work, this principle has an important bearing on the
acquisition by man of some of his mental characteristics.)  Hence the
capacity for high musical development which the savage races of man
possess, may be due either to the practice by our semi-human progenitors of
some rude form of music, or simply to their having acquired the proper
vocal organs for a different purpose.  But in this latter case we must
assume, as in the above instance of parrots, and as seems to occur with
many animals, that they already possessed some sense of melody.

Music arouses in us various emotions, but not the more terrible ones of
horror, fear, rage, etc.  It awakens the gentler feelings of tenderness and
love, which readily pass into devotion.  In the Chinese annals it is said,
"Music hath the power of making heaven descend upon earth."  It likewise
stirs up in us the sense of triumph and the glorious ardour for war.  These
powerful and mingled feelings may well give rise to the sense of sublimity.
We can concentrate, as Dr. Seemann observes, greater intensity of feeling
in a single musical note than in pages of writing.  It is probable that
nearly the same emotions, but much weaker and far less complex, are felt by
birds when the male pours forth his full volume of song, in rivalry with
other males, to captivate the female.  Love is still the commonest theme of
our songs.  As Herbert Spencer remarks, "music arouses dormant sentiments
of which we had not conceived the possibility, and do not know the meaning;
or, as Richter says, tells us of things we have not seen and shall not
see."  Conversely, when vivid emotions are felt and expressed by the
orator, or even in common speech, musical cadences and rhythm are
instinctively used.  The negro in Africa when excited often bursts forth in
song; "another will reply in song, whilst the company, as if touched by a
musical wave, murmur a chorus in perfect unison."  (37.  Winwood Reade,
'The Martyrdom of Man,' 1872, p. 441, and 'African Sketch Book,' 1873, vol.
ii. p. 313.)  Even monkeys express strong feelings in different tones--
anger and impatience by low,--fear and pain by high notes.  (38.  Rengger,
'Saeugethiere von Paraguay,' s. 49.)  The sensations and ideas thus excited
in us by music, or expressed by the cadences of oratory, appear from their
vagueness, yet depth, like mental reversions to the emotions and thoughts
of a long-past age.

All these facts with respect to music and impassioned speech become
intelligible to a certain extent, if we may assume that musical tones and
rhythm were used by our half-human ancestors, during the season of
courtship, when animals of all kinds are excited not only by love, but by
the strong passions of jealousy, rivalry, and triumph.  From the deeply-
laid principle of inherited associations, musical tones in this case would
be likely to call up vaguely and indefinitely the strong emotions of a
long-past age.  As we have every reason to suppose that articulate speech
is one of the latest, as it certainly is the highest, of the arts acquired
by man, and as the instinctive power of producing musical notes and rhythms
is developed low down in the animal series, it would be altogether opposed
to the principle of evolution, if we were to admit that man's musical
capacity has been developed from the tones used in impassioned speech.  We
must suppose that the rhythms and cadences of oratory are derived from
previously developed musical powers.  (39.  See the very interesting
discussion on the 'Origin and Function of Music,' by Mr. Herbert Spencer,
in his collected 'Essays,' 1858, p. 359.  Mr. Spencer comes to an exactly
opposite conclusion to that at which I have arrived.  He concludes, as did
Diderot formerly, that the cadences used in emotional speech afford the
foundation from which music has been developed; whilst I conclude that
musical notes and rhythm were first acquired by the male or female
progenitors of mankind for the sake of charming the opposite sex.  Thus
musical tones became firmly associated with some of the strongest passions
an animal is capable of feeling, and are consequently used instinctively,
or through association when strong emotions are expressed in speech.  Mr.
Spencer does not offer any satisfactory explanation, nor can I, why high or
deep notes should be expressive, both with man and the lower animals, of
certain emotions.  Mr. Spencer gives also an interesting discussion on the
relations between poetry, recitative and song.)  We can thus understand how
it is that music, dancing, song, and poetry are such very ancient arts.  We
may go even further than this, and, as remarked in a former chapter,
believe that musical sounds afforded one of the bases for the development
of language.  (40.  I find in Lord Monboddo's 'Origin of Language,' vol. i.
1774, p. 469, that Dr. Blacklock likewise thought "that the first language
among men was music, and that before our ideas were expressed by articulate
sounds, they were communicated by tones varied according to different
degrees of gravity and acuteness.")

As the males of several quadrumanous animals have their vocal organs much
more developed than in the females, and as a gibbon, one of the
anthropomorphous apes, pours forth a whole octave of musical notes and may
be said to sing, it appears probable that the progenitors of man, either
the males or females or both sexes, before acquiring the power of
expressing their mutual love in articulate language, endeavoured to charm
each other with musical notes and rhythm.  So little is known about the use
of the voice by the Quadrumana during the season of love, that we have no
means of judging whether the habit of singing was first acquired by our
male or female ancestors.  Women are generally thought to possess sweeter
voices than men, and as far as this serves as any guide, we may infer that
they first acquired musical powers in order to attract the other sex.  (41.
See an interesting discussion on this subject by Haeckel, 'Generelle
Morphologie,' B. ii. 1866, s. 246.)  But if so, this must have occurred
long ago, before our ancestors had become sufficiently human to treat and
value their women merely as useful slaves.  The impassioned orator, bard,
or musician, when with his varied tones and cadences he excites the
strongest emotions in his hearers, little suspects that he uses the same
means by which his half-human ancestors long ago aroused each other's
ardent passions, during their courtship and rivalry.

THE INFLUENCE OF BEAUTY IN DETERMINING THE MARRIAGES OF MANKIND.

In civilised life man is largely, but by no means exclusively, influenced
in the choice of his wife by external appearance; but we are chiefly
concerned with primeval times, and our only means of forming a judgment on
this subject is to study the habits of existing semi-civilised and savage
nations.  If it can be shewn that the men of different races prefer women
having various characteristics, or conversely with the women, we have then
to enquire whether such choice, continued during many generations, would
produce any sensible effect on the race, either on one sex or both
according to the form of inheritance which has prevailed.

It will be well first to shew in some detail that savages pay the greatest
attention to their personal appearance.  (42.  A full and excellent account
of the manner in which savages in all parts of the world ornament
themselves, is given by the Italian traveller, Professor Mantegazza, 'Rio
de la Plata, Viaggi e Studi,' 1867, pp. 525-545; all the following
statements, when other references are not given, are taken from this work.
See, also, Waitz, 'Introduction to Anthropology,' Eng. translat. vol. i.
1863, p. 275, et passim.  Lawrence also gives very full details in his
'Lectures on Physiology,' 1822.  Since this chapter was written Sir J.
Lubbock has published his 'Origin of Civilisation,' 1870, in which there is
an interesting chapter on the present subject, and from which (pp. 42, 48)
I have taken some facts about savages dyeing their teeth and hair, and
piercing their teeth.)  That they have a passion for ornament is notorious;
and an English philosopher goes so far as to maintain, that clothes were
first made for ornament and not for warmth.  As Professor Waitz remarks,
"however poor and miserable man is, he finds a pleasure in adorning
himself."  The extravagance of the naked Indians of South America in
decorating themselves is shewn "by a man of large stature gaining with
difficulty enough by the labour of a fortnight to procure in exchange the
chica necessary to paint himself red."  (43.  Humboldt, 'Personal
Narrative,' Eng. translat. vol. iv. p. 515; on the imagination shewn in
painting the body, p. 522; on modifying the form of the calf of the leg, p.
466.)  The ancient barbarians of Europe during the Reindeer period brought
to their caves any brilliant or singular objects which they happened to
find.  Savages at the present day everywhere deck themselves with plumes,
necklaces, armlets, ear-rings, etc.  They paint themselves in the most
diversified manner.  "If painted nations," as Humboldt observes, "had been
examined with the same attention as clothed nations, it would have been
perceived that the most fertile imagination and the most mutable caprice
have created the fashions of painting, as well as those of garments."

In one part of Africa the eyelids are coloured black; in another the nails
are coloured yellow or purple.  In many places the hair is dyed of various
tints.  In different countries the teeth are stained black, red, blue,
etc., and in the Malay Archipelago it is thought shameful to have white
teeth "like those of a dog."  Not one great country can be named, from the
polar regions in the north to New Zealand in the south, in which the
aborigines do not tattoo themselves.  This practice was followed by the
Jews of old, and by the ancient Britons.  In Africa some of the natives
tattoo themselves, but it is a much more common practice to raise
protuberances by rubbing salt into incisions made in various parts of the
body; and these are considered by the inhabitants of Kordofan and Darfur
"to be great personal attractions."  In the Arab countries no beauty can be
perfect until the cheeks "or temples have been gashed."  (44.  'The Nile
Tributaries,' 1867; 'The Albert N'yanza,' 1866, vol. i. p. 218.)  In South
America, as Humboldt remarks, "a mother would be accused of culpable
indifference towards her children, if she did not employ artificial means
to shape the calf of the leg after the fashion of the country."  In the Old
and New Worlds the shape of the skull was formerly modified during infancy
in the most extraordinary manner, as is still the case in many places, and
such deformities are considered ornamental.  For instance, the savages of
Colombia (45.  Quoted by Prichard, 'Physical History of Mankind,' 4th ed.
vol. i. 1851, p. 321.) deem a much flattened head "an essential point of
beauty."

The hair is treated with especial care in various countries; it is allowed
to grow to full length, so as to reach to the ground, or is combed into "a
compact frizzled mop, which is the Papuan's pride and glory."  (46.  On the
Papuans, Wallace, 'The Malay Archipelago,' vol. ii. p. 445.  On the
coiffure of the Africans, Sir S. Baker, 'The Albert N'yanza,' vol. i. p.
210.)  In northern Africa "a man requires a period of from eight to ten
years to perfect his coiffure."  With other nations the head is shaved, and
in parts of South America and Africa even the eyebrows and eyelashes are
eradicated.  The natives of the Upper Nile knock out the four front teeth,
saying that they do not wish to resemble brutes.  Further south, the
Batokas knock out only the two upper incisors, which, as Livingstone (47.
'Travels,' p. 533.) remarks, gives the face a hideous appearance, owing to
the prominence of the lower jaw; but these people think the presence of the
incisors most unsightly, and on beholding some Europeans, cried out, "Look
at the great teeth!"  The chief Sebituani tried in vain to alter this
fashion.  In various parts of Africa and in the Malay Archipelago the
natives file the incisors into points like those of a saw, or pierce them
with holes, into which they insert studs.

As the face with us is chiefly admired for its beauty, so with savages it
is the chief seat of mutilation.  In all quarters of the world the septum,
and more rarely the wings of the nose are pierced; rings, sticks, feathers,
and other ornaments being inserted into the holes.  The ears are everywhere
pierced and similarly ornamented, and with the Botocudos and Lenguas of
South America the hole is gradually so much enlarged that the lower edge
touches the shoulder.  In North and South America and in Africa either the
upper or lower lip is pierced; and with the Botocudos the hole in the lower
lip is so large that a disc of wood, four inches in diameter, is placed in
it.  Mantegazza gives a curious account of the shame felt by a South
American native, and of the ridicule which he excited, when he sold his
tembeta,--the large coloured piece of wood which is passed through the
hole.  In Central Africa the women perforate the lower lip and wear a
crystal, which, from the movement of the tongue, has "a wriggling motion,
indescribably ludicrous during conversation."  The wife of the chief of
Latooka told Sir S. Baker (49.  'The Albert N'yanza,' 1866, vol. i. p.
217.) that Lady Baker "would be much improved if she would extract her four
front teeth from the lower jaw, and wear the long pointed polished crystal
in her under lip."  Further south with the Makalolo, the upper lip is
perforated, and a large metal and bamboo ring, called a pelele, is worn in
the hole.  "This caused the lip in one case to project two inches beyond
the tip of the nose; and when the lady smiled, the contraction of the
muscles elevated it over the eyes.  'Why do the women wear these things?'
the venerable chief, Chinsurdi, was asked.  Evidently surprised at such a
stupid question, he replied, 'For beauty!  They are the only beautiful
things women have; men have beards, women have none.  What kind of a person
would she be without the pelele?  She would not be a woman at all with a
mouth like a man, but no beard.'"  (49.  Livingstone, 'British
Association,' 1860; report given in the 'Athenaeum,' July 7, 1860, p. 29.)

Hardly any part of the body, which can be unnaturally modified, has
escaped.  The amount of suffering thus caused must have been extreme, for
many of the operations require several years for their completion, so that
the idea of their necessity must be imperative.  The motives are various;
the men paint their bodies to make themselves appear terrible in battle;
certain mutilations are connected with religious rites, or they mark the
age of puberty, or the rank of the man, or they serve to distinguish the
tribes.  Amongst savages the same fashions prevail for long periods (50.
Sir S. Baker (ibid. vol. i. p. 210) speaking of the natives of Central
Africa says, "every tribe has a distinct and unchanging fashion for
dressing the hair."  See Agassiz ('Journey in Brazil,' 1868, p. 318) on
invariability of the tattooing of Amazonian Indians.), and thus
mutilations, from whatever cause first made, soon come to be valued as
distinctive marks.  But self-adornment, vanity, and the admiration of
others, seem to be the commonest motives.  In regard to tattooing, I was
told by the missionaries in New Zealand that when they tried to persuade
some girls to give up the practice, they answered, "We must just have a few
lines on our lips; else when we grow old we shall be so very ugly."  With
the men of New Zealand, a most capable judge (51.  Rev. R. Taylor, 'New
Zealand and its Inhabitants,' 1855, p. 152.) says, "to have fine tattooed
faces was the great ambition of the young, both to render themselves
attractive to the ladies, and conspicuous in war."  A star tattooed on the
forehead and a spot on the chin are thought by the women in one part of
Africa to be irresistible attractions.  (52.  Mantegazza, 'Viaggi e Studi,'
p. 542.)  In most, but not all parts of the world, the men are more
ornamented than the women, and often in a different manner; sometimes,
though rarely, the women are hardly at all ornamented.  As the women are
made by savages to perform the greatest share of the work, and as they are
not allowed to eat the best kinds of food, so it accords with the
characteristic selfishness of man that they should not be allowed to
obtain, or use the finest ornaments.  Lastly, it is a remarkable fact, as
proved by the foregoing quotations, that the same fashions in modifying the
shape of the head, in ornamenting the hair, in painting, tattooing, in
perforating the nose, lips, or ears, in removing or filing the teeth, etc.,
now prevail, and have long prevailed, in the most distant quarters of the
world.  It is extremely improbable that these practices, followed by so
many distinct nations, should be due to tradition from any common source.
They indicate the close similarity of the mind of man, to whatever race he
may belong, just as do the almost universal habits of dancing,
masquerading, and making rude pictures.

Having made these preliminary remarks on the admiration felt by savages for
various ornaments, and for deformities most unsightly in our eyes, let us
see how far the men are attracted by the appearance of their women, and
what are their ideas of beauty.  I have heard it maintained that savages
are quite indifferent about the beauty of their women, valuing them solely
as slaves; it may therefore be well to observe that this conclusion does
not at all agree with the care which the women take in ornamenting
themselves, or with their vanity.  Burchell (53.  'Travels in South
Africa,' 1824, vol. i. p. 414.) gives an amusing account of a Bush-woman
who used as much grease, red ochre, and shining powder "as would have
ruined any but a very rich husband."  She displayed also "much vanity and
too evident a consciousness of her superiority."  Mr. Winwood Reade informs
me that the negroes of the West Coast often discuss the beauty of their
women.  Some competent observers have attributed the fearfully common
practice of infanticide partly to the desire felt by the women to retain
their good looks.  (54.  See, for references, Gerland, 'Ueber das
Aussterben der Naturvoelker,' 1868, ss. 51, 53, 55; also Azara, 'Voyages,'
etc., tom. ii. p. 116.)  In several regions the women wear charms and use
love-philters to gain the affections of the men; and Mr. Brown enumerates
four plants used for this purpose by the women of North-Western America.
(55.  On the vegetable productions used by the North-Western American
Indians, see 'Pharmaceutical Journal,' vol. x.)

Hearne (56.  'A Journey from Prince of Wales Fort,' 8vo. ed. 1796, p. 89.),
an excellent observer, who lived many years with the American Indians,
says, in speaking of the women, "Ask a Northern Indian what is beauty, and
he will answer, a broad flat face, small eyes, high cheek-bones, three or
four broad black lines across each cheek, a low forehead, a large broad
chin, a clumsy hook nose, a tawny hide, and breasts hanging down to the
belt."  Pallas, who visited the northern parts of the Chinese empire, says,
"those women are preferred who have the Mandschu form; that is to say, a
broad face, high cheek-bones, very broad noses, and enormous ears"(57.
Quoted by Prichard, 'Physical History of Mankind,' 3rd ed. vol. iv. 1844,
p. 519; Vogt, 'Lectures on Man,' Eng. translat. p. 129.  On the opinion of
the Chinese on the Cingalese, E. Tennent, 'Ceylon,' 1859, vol. ii. p.
107.); and Vogt remarks that the obliquity of the eye, which is proper to
the Chinese and Japanese, is exaggerated in their pictures for the purpose,
as it "seems, of exhibiting its beauty, as contrasted with the eye of the
red-haired barbarians."  It is well known, as Huc repeatedly remarks, that
the Chinese of the interior think Europeans hideous, with their white skins
and prominent noses.  The nose is far from being too prominent, according
to our ideas, in the natives of Ceylon; yet "the Chinese in the seventh
century, accustomed to the flat features of the Mongol races, were
surprised at the prominent noses of the Cingalese; and Thsang described
them as having 'the beak of a bird, with the body of a man.'"

Finlayson, after minutely describing the people of Cochin China, says that
their rounded heads and faces are their chief characteristics; and, he
adds, "the roundness of the whole countenance is more striking in the
women, who are reckoned beautiful in proportion as they display this form
of face."  The Siamese have small noses with divergent nostrils, a wide
mouth, rather thick lips, a remarkably large face, with very high and broad
cheek-bones.  It is, therefore, not wonderful that "beauty, according to
our notion, is a stranger to them.  Yet they consider their own females to
be much more beautiful than those of Europe."  (58.  Prichard, as taken
from Crawfurd and Finlayson, 'Phys. Hist. of Mankind,' vol. iv. pp. 534,
535.)

It is well known that with many Hottentot women the posterior part of the
body projects in a wonderful manner; they are steatopygous; and Sir Andrew
Smith is certain that this peculiarity is greatly admired by the men.  (59.
Idem illustrissimus viator dixit mihi praecinctorium vel tabulam foeminae,
quod nobis teterrimum est, quondam permagno aestimari ab hominibus in hac
gente.  Nunc res mutata est, et censent talem conformationem minime
optandam esse.)  He once saw a woman who was considered a beauty, and she
was so immensely developed behind, that when seated on level ground she
could not rise, and had to push herself along until she came to a slope.
Some of the women in various negro tribes have the same peculiarity; and,
according to Burton, the Somal men are said to choose their wives by
ranging them in a line, and by picking her out who projects farthest a
tergo.  Nothing can be more hateful to a negro than the opposite form."
(60.  The 'Anthropological Review,' November 1864, p. 237.  For additional
references, see Waitz, 'Introduction to Anthropology,' Eng. translat.,
1863, vol. i. p. 105.)

With respect to colour, the negroes rallied Mungo Park on the whiteness of
his skin and the prominence of his nose, both of which they considered as
"unsightly and unnatural conformations."  He in return praised the glossy
jet of their skins and the lovely depression of their noses; this they said
was "honeymouth," nevertheless they gave him food.  The African Moors,
also, "knitted their brows and seemed to shudder" at the whiteness of his
skin.  On the eastern coast, the negro boys when they saw Burton, cried
out, "Look at the white man; does he not look like a white ape?"  On the
western coast, as Mr. Winwood Reade informs me, the negroes admire a very
black skin more than one of a lighter tint.  But their horror of whiteness
may be attributed, according to this same traveller, partly to the belief
held by most negroes that demons and spirits are white, and partly to their
thinking it a sign of ill-health.

The Banyai of the more southern part of the continent are negroes, but "a
great many of them are of a light coffee-and-milk colour, and, indeed, this
colour is considered handsome throughout the whole country"; so that here
we have a different standard of taste.  With the Kaffirs, who differ much
from negroes, "the skin, except among the tribes near Delagoa Bay, is not
usually black, the prevailing colour being a mixture of black and red, the
most common shade being chocolate.  Dark complexions, as being most common,
are naturally held in the highest esteem.  To be told that he is light-
coloured, or like a white man, would be deemed a very poor compliment by a
Kaffir.  I have heard of one unfortunate man who was so very fair that no
girl would marry him."  One of the titles of the Zulu king is, "You who are
black."  (61.  Mungo Park's 'Travels in Africa,' 4to. 1816, pp. 53, 131.
Burton's statement is quoted by Schaaffhausen, 'Archiv. fur Anthropologie,'
1866, s. 163.  On the Banyai, Livingstone, 'Travels,' p. 64.  On the
Kaffirs, the Rev. J. Shooter, 'The Kafirs of Natal and the Zulu Country,'
1857, p. 1.)  Mr. Galton, in speaking to me about the natives of S. Africa,
remarked that their ideas of beauty seem very different from ours; for in
one tribe two slim, slight, and pretty girls were not admired by the
natives.

Turning to other quarters of the world; in Java, a yellow, not a white
girl, is considered, according to Madame Pfeiffer, a beauty.  A man of
Cochin China "spoke with contempt of the wife of the English Ambassador,
that she had white teeth like a dog, and a rosy colour like that of potato-
flowers."  We have seen that the Chinese dislike our white skin, and that
the N. Americans admire "a tawny hide."  In S. America, the Yuracaras, who
inhabit the wooded, damp slopes of the eastern Cordillera, are remarkably
pale-coloured, as their name in their own language expresses; nevertheless
they consider European women as very inferior to their own.  (62.  For the
Javans and Cochin-Chinese, see Waitz, 'Introduct. to Anthropology,' Eng.
translat. vol. i. p. 305.  On the Yuracaras, A. d'Orbigny, as quoted in
Prichard, 'Physical History of Mankind,' vol. v. 3rd ed. p. 476.)

In several of the tribes of North America the hair on the head grows to a
wonderful length; and Catlin gives a curious proof how much this is
esteemed, for the chief of the Crows was elected to this office from having
the longest hair of any man in the tribe, namely ten feet and seven inches.
The Aymaras and Quichuas of S. America, likewise have very long hair; and
this, as Mr. D. Forbes informs me, is so much valued as a beauty, that
cutting it off was the severest punishment which he could inflict on them.
In both the Northern and Southern halves of the continent the natives
sometimes increase the apparent length of their hair by weaving into it
fibrous substances.  Although the hair on the head is thus cherished, that
on the face is considered by the North American Indians "as very vulgar,"
and every hair is carefully eradicated.  This practice prevails throughout
the American continent from Vancouver's Island in the north to Tierra del
Fuego in the south.  When York Minster, a Fuegian on board the "Beagle,"
was taken back to his country, the natives told him be ought to pull out
the few short hairs on his face.  They also threatened a young missionary,
who was left for a time with them, to strip him naked, and pluck the hair
from his face and body, yet he was far from being a hairy man.  This
fashion is carried so far that the Indians of Paraguay eradicate their
eyebrows and eyelashes, saying that they do not wish to be like horses.
(63.  'North American Indians,' by G. Catlin, 3rd ed., 1842, vol. i. p. 49;
vol. ii, p. 227.  On the natives of Vancouver's Island, see Sproat, 'Scenes
and Studies of Savage Life,' 1868, p. 25.  On the Indians of Paraguay,
Azara, 'Voyages,' tom. ii. p. 105.)

It is remarkable that throughout the world the races which are almost
completely destitute of a beard dislike hairs on the face and body, and
take pains to eradicate them.  The Kalmucks are beardless, and they are
well known, like the Americans, to pluck out all straggling hairs; and so
it is with the Polynesians, some of the Malays, and the Siamese.  Mr.
Veitch states that the Japanese ladies "all objected to our whiskers,
considering them very ugly, and told us to cut them off, and be like
Japanese men."  The New Zealanders have short, curled beards; yet they
formerly plucked out the hairs on the face.  They had a saying that "there
is no woman for a hairy man;" but it would appear that the fashion has
changed in New Zealand, perhaps owing to the presence of Europeans, and I
am assured that beards are now admired by the Maories.  (64.  On the
Siamese, Prichard, ibid. vol. iv. p. 533.  On the Japanese, Veitch in
'Gardeners' Chronicle,' 1860, p. 1104.  On the New Zealanders, Mantegazza,
'Viaggi e Studi,' 1867, p. 526.  For the other nations mentioned, see
references in Lawrence, 'Lectures on Physiology,' etc., 1822, p. 272.)

On the other hand, bearded races admire and greatly value their beards;
among the Anglo-Saxons every part of the body had a recognised value; "the
loss of the beard being estimated at twenty shillings, while the breaking
of a thigh was fixed at only twelve."  (65.  Lubbock, 'Origin of
Civilisation,' 1870, p. 321.)  In the East men swear solemnly by their
beards.  We have seen that Chinsurdi, the chief of the Makalolo in Africa,
thought that beards were a great ornament.  In the Pacific the Fijian's
beard is "profuse and bushy, and is his greatest pride"; whilst the
inhabitants of the adjacent archipelagoes of Tonga and Samoa are
"beardless, and abhor a rough chin."  In one island alone of the Ellice
group "the men are heavily bearded, and not a little proud thereof."  (66.
Dr. Barnard Davis quotes Mr. Prichard and others for these facts in regard
to the Polynesians, in 'Anthropolog. Review,' April 1870, pp. 185, 191.)

We thus see how widely the different races of man differ in their taste for
the beautiful.  In every nation sufficiently advanced to have made effigies
of their gods or of their deified rulers, the sculptors no doubt have
endeavoured to express their highest ideal of beauty and grandeur.  (67.
Ch. Comte has remarks to this effect in his 'Traite de Legislation,' 3rd
ed. 1837, p. 136.)  Under this point of view it is well to compare in our
mind the Jupiter or Apollo of the Greeks with the Egyptian or Assyrian
statues; and these with the hideous bas-reliefs on the ruined buildings of
Central America.

I have met with very few statements opposed to this conclusion.  Mr.
Winwood Reade, however, who has had ample opportunities for observation,
not only with the negroes of the West Coast of Africa, but with those of
the interior who have never associated with Europeans, is convinced that
their ideas of beauty are ON THE WHOLE the same as ours; and Dr. Rohlfs
writes to me to the same effect with respect to Bornu and the countries
inhabited by the Pullo tribes.  Mr. Reade found that he agreed with the
negroes in their estimation of the beauty of the native girls; and that
their appreciation of the beauty of European women corresponded with ours.
They admire long hair, and use artificial means to make it appear abundant;
they admire also a beard, though themselves very scantily provided.  Mr.
Reade feels doubtful what kind of nose is most appreciated; a girl has been
heard to say, "I do not want to marry him, he has got no nose"; and this
shews that a very flat nose is not admired.  We should, however, bear in
mind that the depressed, broad noses and projecting jaws of the negroes of
the West Coast are exceptional types with the inhabitants of Africa.
Notwithstanding the foregoing statements, Mr. Reade admits that negroes "do
not like the colour of our skin; they look on blue eyes with aversion, and
they think our noses too long and our lips too thin."  He does not think it
probable that negroes would ever prefer the most beautiful European woman,
on the mere grounds of physical admiration, to a good-looking negress.
(68.  The 'African Sketch Book,' vol. ii. 1873, pp. 253, 394, 521.  The
Fuegians, as I have been informed by a missionary who long resided with
them, consider European women as extremely beautiful; but from what we have
seen of the judgment of the other aborigines of America, I cannot but think
that this must be a mistake, unless indeed the statement refers to the few
Fuegians who have lived for some time with Europeans, and who must consider
us as superior beings.  I should add that a most experienced observer,
Capt. Burton, believes that a woman whom we consider beautiful is admired
throughout the world.  'Anthropological Review,' March, 1864, p. 245.)

The general truth of the principle, long ago insisted on by Humboldt (69.
'Personal Narrative,' Eng. translat. vol. iv. p. 518, and elsewhere.
Mantegazza, in his 'Viaggi e Studi,' strongly insists on this same
principle.), that man admires and often tries to exaggerate whatever
characters nature may have given him, is shewn in many ways.  The practice
of beardless races extirpating every trace of a beard, and often all the
hairs on the body affords one illustration.  The skull has been greatly
modified during ancient and modern times by many nations; and there can be
little doubt that this has been practised, especially in N. and S. America,
in order to exaggerate some natural and admired peculiarity.  Many American
Indians are known to admire a head so extremely flattened as to appear to
us idiotic.  The natives on the north-western coast compress the head into
a pointed cone; and it is their constant practice to gather the hair into a
knot on the top of the head, for the sake, as Dr. Wilson remarks, "of
increasing the apparent elevation of the favourite conoid form."  The
inhabitants of Arakhan admire a broad, smooth forehead, and in order to
produce it, they fasten a plate of lead on the heads of the new-born
children.  On the other hand, "a broad, well-rounded occiput is considered
a great beauty" by the natives of the Fiji Islands.  (70.  On the skulls of
the American tribes, see Nott and Gliddon, 'Types of Mankind,' 1854, p.
440; Prichard, 'Physical History of Mankind,' vol. i. 3rd ed. p. 321; on
the natives of Arakhan, ibid. vol. iv. p. 537.  Wilson, 'Physical
Ethnology,' Smithsonian Institution, 1863, p. 288; on the Fijians, p. 290.
Sir J. Lubbock ('Prehistoric Times,' 2nd ed. 1869, p. 506) gives an
excellent resume on this subject.)

As with the skull, so with the nose; the ancient Huns during the age of
Attila were accustomed to flatten the noses of their infants with bandages,
"for the sake of exaggerating a natural conformation."  With the Tahitians,
to be called LONG-NOSE is considered as an insult, and they compress the
noses and foreheads of their children for the sake of beauty.  The same
holds with the Malays of Sumatra, the Hottentots, certain Negroes, and the
natives of Brazil.  (71.  On the Huns, Godron, 'De l'Espece,' tom. ii.
1859, p. 300.  On the Tahitians, Waitz, 'Anthropology,' Eng. translat. vol.
i. p. 305.  Marsden, quoted by Prichard, 'Phys. Hist. of Mankind,' 3rd
edit. vol. v. p. 67.  Lawrence, 'Lectures on Physiology,' p. 337.)  The
Chinese have by nature unusually small feet (72.  This fact was ascertained
in the 'Reise der Novara:  Anthropolog. Theil.' Dr. Weisbach, 1867, s.
265.); and it is well known that the women of the upper classes distort
their feet to make them still smaller.  Lastly, Humboldt thinks that the
American Indians prefer colouring their bodies with red paint in order to
exaggerate their natural tint; and until recently European women added to
their naturally bright colours by rouge and white cosmetics; but it may be
doubted whether barbarous nations have generally had any such intention in
painting themselves.

In the fashions of our own dress we see exactly the same principle and the
same desire to carry every point to an extreme; we exhibit, also, the same
spirit of emulation.  But the fashions of savages are far more permanent
than ours; and whenever their bodies are artificially modified, this is
necessarily the case.  The Arab women of the Upper Nile occupy about three
days in dressing their hair; they never imitate other tribes, "but simply
vie with each other in the superlativeness of their own style."  Dr.
Wilson, in speaking of the compressed skulls of various American races,
adds, "such usages are among the least eradicable, and long survive the
shock of revolutions that change dynasties and efface more important
national peculiarities."  (73.  'Smithsonian Institution,' 1863, p. 289.
On the fashions of Arab women, Sir S. Baker, 'The Nile Tributaries,' 1867,
p. 121.)  The same principle comes into play in the art of breeding; and we
can thus understand, as I have elsewhere explained (74.  The 'Variation of
Animals and Plants under Domestication,' vol. i. p. 214; vol. ii. p. 240.),
the wonderful development of the many races of animals and plants, which
have been kept merely for ornament.  Fanciers always wish each character to
be somewhat increased; they do not admire a medium standard; they certainly
do not desire any great and abrupt change in the character of their breeds;
they admire solely what they are accustomed to, but they ardently desire to
see each characteristic feature a little more developed.

The senses of man and of the lower animals seem to be so constituted that
brilliant colours and certain forms, as well as harmonious and rhythmical
sounds, give pleasure and are called beautiful; but why this should be so
we know not.  It is certainly not true that there is in the mind of man any
universal standard of beauty with respect to the human body.  It is,
however, possible that certain tastes may in the course of time become
inherited, though there is no evidence in favour of this belief:  and if
so, each race would possess its own innate ideal standard of beauty.  It
has been argued (75.  Schaaffhausen, 'Archiv. fuer Anthropologie,' 1866, s.
164.) that ugliness consists in an approach to the structure of the lower
animals, and no doubt this is partly true with the more civilised nations,
in which intellect is highly appreciated; but this explanation will hardly
apply to all forms of ugliness.  The men of each race prefer what they are
accustomed to; they cannot endure any great change; but they like variety,
and admire each characteristic carried to a moderate extreme.  (76.  Mr.
Bain has collected ('Mental and Moral Science,' 1868, pp. 304-314) about a
dozen more or less different theories of the idea of beauty; but none is
quite the same as that here given.)  Men accustomed to a nearly oval face,
to straight and regular features, and to bright colours, admire, as we
Europeans know, these points when strongly developed.  On the other hand,
men accustomed to a broad face, with high cheek-bones, a depressed nose,
and a black skin, admire these peculiarities when strongly marked.  No
doubt characters of all kinds may be too much developed for beauty.  Hence
a perfect beauty, which implies many characters modified in a particular
manner, will be in every race a prodigy.  As the great anatomist Bichat
long ago said, if every one were cast in the same mould, there would be no
such thing as beauty.  If all our women were to become as beautiful as the
Venus de' Medici, we should for a time be charmed; but we should soon wish
for variety; and as soon as we had obtained variety, we should wish to see
certain characters a little exaggerated beyond the then existing common
standard.


CHAPTER XX.

SECONDARY SEXUAL CHARACTERS OF MAN--continued.

On the effects of the continued selection of women according to a different
standard of beauty in each race--On the causes which interfere with sexual
selection in civilised and savage nations--Conditions favourable to sexual
selection during primeval times--On the manner of action of sexual
selection with mankind--On the women in savage tribes having some power to
choose their husbands--Absence of hair on the body, and development of the
beard--Colour of the skin--Summary.

We have seen in the last chapter that with all barbarous races ornaments,
dress, and external appearance are highly valued; and that the men judge of
the beauty of their women by widely different standards.  We must next
inquire whether this preference and the consequent selection during many
generations of those women, which appear to the men of each race the most
attractive, has altered the character either of the females alone, or of
both sexes.  With mammals the general rule appears to be that characters of
all kinds are inherited equally by the males and females; we might
therefore expect that with mankind any characters gained by the females or
by the males through sexual selection would commonly be transferred to the
offspring of both sexes.  If any change has thus been effected, it is
almost certain that the different races would be differently modified, as
each has its own standard of beauty.

With mankind, especially with savages, many causes interfere with the
action of sexual selection as far as the bodily frame is concerned.
Civilised men are largely attracted by the mental charms of women, by their
wealth, and especially by their social position; for men rarely marry into
a much lower rank.  The men who succeed in obtaining the more beautiful
women will not have a better chance of leaving a long line of descendants
than other men with plainer wives, save the few who bequeath their fortunes
according to primogeniture.  With respect to the opposite form of
selection, namely, of the more attractive men by the women, although in
civilised nations women have free or almost free choice, which is not the
case with barbarous races, yet their choice is largely influenced by the
social position and wealth of the men; and the success of the latter in
life depends much on their intellectual powers and energy, or on the fruits
of these same powers in their forefathers.  No excuse is needed for
treating this subject in some detail; for, as the German philosopher
Schopenhauer remarks, "the final aim of all love intrigues, be they comic
or tragic, is really of more importance than all other ends in human life.
What it all turns upon is nothing less than the composition of the next
generation...It is not the weal or woe of any one individual, but that of
the human race to come, which is here at stake."  (1.  'Schopenhauer and
Darwinism,' in 'Journal of Anthropology,' Jan. 1871, p. 323.

There is, however, reason to believe that in certain civilised and semi-
civilised nations sexual selection has effected something in modifying the
bodily frame of some of the members.  Many persons are convinced, as it
appears to me with justice, that our aristocracy, including under this term
all wealthy families in which primogeniture has long prevailed, from having
chosen during many generations from all classes the more beautiful women as
their wives, have become handsomer, according to the European standard,
than the middle classes; yet the middle classes are placed under equally
favourable conditions of life for the perfect development of the body.
Cook remarks that the superiority in personal appearance "which is
observable in the erees or nobles in all the other islands (of the Pacific)
is found in the Sandwich Islands"; but this may be chiefly due to their
better food and manner of life.

The old traveller Chardin, in describing the Persians, says their "blood is
now highly refined by frequent intermixtures with the Georgians and
Circassians, two nations which surpass all the world in personal beauty.
There is hardly a man of rank in Persia who is not born of a Georgian or
Circassian mother."  He adds that they inherit their beauty, "not from
their ancestors, for without the above mixture, the men of rank in Persia,
who are descendants of the Tartars, would be extremely ugly."  (2.  These
quotations are taken from Lawrence ('Lectures on Physiology,' etc., 1822,
p. 393), who attributes the beauty of the upper classes in England to the
men having long selected the more beautiful women.)  Here is a more curious
case; the priestesses who attended the temple of Venus Erycina at San-
Giuliano in Sicily, were selected for their beauty out of the whole of
Greece; they were not vestal virgins, and Quatrefages (3.  'Anthropologie,'
'Revue des Cours Scientifiques,' Oct. 1868, p. 721.), who states the
foregoing fact, says that the women of San-Giuliano are now famous as the
most beautiful in the island, and are sought by artists as models.  But it
is obvious that the evidence in all the above cases is doubtful.

The following case, though relating to savages, is well worth giving for
its curiosity.  Mr. Winwood Reade informs me that the Jollofs, a tribe of
negroes on the west coast of Africa, "are remarkable for their uniformly
fine appearance."  A friend of his asked one of these men, "How is it that
every one whom I meet is so fine looking, not only your men but your
women?"  The Jollof answered, "It is very easily explained:  it has always
been our custom to pick out our worst-looking slaves and to sell them."  It
need hardly be added that with all savages, female slaves serve as
concubines.  That this negro should have attributed, whether rightly or
wrongly, the fine appearance of his tribe to the long-continued elimination
of the ugly women is not so surprising as it may at first appear; for I
have elsewhere shewn (4.  'Variation of Animals and Plants under
Domestication,' vol. i. p. 207.) that negroes fully appreciate the
importance of selection in the breeding of their domestic animals, and I
could give from Mr. Reade additional evidence on this head.

THE CAUSES WHICH PREVENT OR CHECK THE ACTION OF SEXUAL SELECTION WITH
SAVAGES.

The chief causes are, first, so-called communal marriages or promiscuous
intercourse; secondly, the consequences of female infanticide; thirdly,
early betrothals; and lastly, the low estimation in which women are held,
as mere slaves.  These four points must be considered in some detail.

It is obvious that as long as the pairing of man, or of any other animal,
is left to mere chance, with no choice exerted by either sex, there can be
no sexual selection; and no effect will be produced on the offspring by
certain individuals having had an advantage over others in their courtship.
Now it is asserted that there exist at the present day tribes which
practise what Sir J. Lubbock by courtesy calls communal marriages; that is,
all the men and women in the tribe are husbands and wives to one another.
The licentiousness of many savages is no doubt astonishing, but it seems to
me that more evidence is requisite, before we fully admit that their
intercourse is in any case promiscuous.  Nevertheless all those who have
most closely studied the subject (5.  Sir J. Lubbock, 'The Origin of
Civilisation,' 1870, chap. iii. especially pp. 60-67.  Mr. M'Lennan, in his
extremely valuable work on 'Primitive Marriage,' 1865, p. 163, speaks of
the union of the sexes "in the earliest times as loose, transitory, and in
some degree promiscuous."  Mr. M'Lennan and Sir J. Lubbock have collected
much evidence on the extreme licentiousness of savages at the present time.
Mr. L.H. Morgan, in his interesting memoir of the classificatory system of
relationship.  ('Proceedings of the American Academy of Sciences,' vol.
vii. Feb. 1868, p. 475), concludes that polygamy and all forms of marriage
during primeval times were essentially unknown.  It appears also, from Sir
J. Lubbock's work, that Bachofen likewise believes that communal
intercourse originally prevailed.), and whose judgment is worth much more
than mine, believe that communal marriage (this expression being variously
guarded) was the original and universal form throughout the world,
including therein the intermarriage of brothers and sisters.  The late Sir
A. Smith, who had travelled widely in S. Africa, and knew much about the
habits of savages there and elsewhere, expressed to me the strongest
opinion that no race exists in which woman is considered as the property of
the community.  I believe that his judgment was largely determined by what
is implied by the term marriage.  Throughout the following discussion I use
the term in the same sense as when naturalists speak of animals as
monogamous, meaning thereby that the male is accepted by or chooses a
single female, and lives with her either during the breeding-season or for
the whole year, keeping possession of her by the law of might; or, as when
they speak of a polygamous species, meaning that the male lives with
several females.  This kind of marriage is all that concerns us here, as it
suffices for the work of sexual selection.  But I know that some of the
writers above referred to imply by the term marriage a recognised right
protected by the tribe.

The indirect evidence in favour of the belief of the former prevalence of
communal marriages is strong, and rests chiefly on the terms of
relationship which are employed between the members of the same tribe,
implying a connection with the tribe, and not with either parent.  But the
subject is too large and complex for even an abstract to be here given, and
I will confine myself to a few remarks.  It is evident in the case of such
marriages, or where the marriage tie is very loose, that the relationship
of the child to its father cannot be known.  But it seems almost incredible
that the relationship of the child to its mother should ever be completely
ignored, especially as the women in most savage tribes nurse their infants
for a long time.  Accordingly, in many cases the lines of descent are
traced through the mother alone, to the exclusion of the father.  But in
other cases the terms employed express a connection with the tribe alone,
to the exclusion even of the mother.  It seems possible that the connection
between the related members of the same barbarous tribe, exposed to all
sorts of danger, might be so much more important, owing to the need of
mutual protection and aid, than that between the mother and her child, as
to lead to the sole use of terms expressive of the former relationships;
but Mr. Morgan is convinced that this view is by no means sufficient.

The terms of relationship used in different parts of the world may be
divided, according to the author just quoted, into two great classes, the
classificatory and descriptive, the latter being employed by us.  It is the
classificatory system which so strongly leads to the belief that communal
and other extremely loose forms of marriage were originally universal.  But
as far as I can see, there is no necessity on this ground for believing in
absolutely promiscuous intercourse; and I am glad to find that this is Sir
J. Lubbock's view.  Men and women, like many of the lower animals, might
formerly have entered into strict though temporary unions for each birth,
and in this case nearly as much confusion would have arisen in the terms of
relationship as in the case of promiscuous intercourse.  As far as sexual
selection is concerned, all that is required is that choice should be
exerted before the parents unite, and it signifies little whether the
unions last for life or only for a season.

Besides the evidence derived from the terms of relationship, other lines of
reasoning indicate the former wide prevalence of communal marriage.  Sir J.
Lubbock accounts for the strange and widely-extended habit of exogamy--that
is, the men of one tribe taking wives from a distinct tribe,--by communism
having been the original form of intercourse; so that a man never obtained
a wife for himself unless he captured her from a neighbouring and hostile
tribe, and then she would naturally have become his sole and valuable
property.  Thus the practice of capturing wives might have arisen; and from
the honour so gained it might ultimately have become the universal habit.
According to Sir J. Lubbock (6.  'Address to British Association On the
Social and Religious Condition of the Lower Races of Man,' 1870, p. 20.),
we can also thus understand "the necessity of expiation for marriage as an
infringement of tribal rites, since according to old ideas, a man had no
right to appropriate to himself that which belonged to the whole tribe."
Sir J. Lubbock further gives a curious body of facts shewing that in old
times high honour was bestowed on women who were utterly licentious; and
this, as he explains, is intelligible, if we admit that promiscuous
intercourse was the aboriginal, and therefore long revered custom of the
tribe.  (7.  'Origin of Civilisation,' 1870, p. 86.  In the several works
above quoted, there will be found copious evidence on relationship through
the females alone, or with the tribe alone.)

Although the manner of development of the marriage tie is an obscure
subject, as we may infer from the divergent opinions on several points
between the three authors who have studied it most closely, namely, Mr.
Morgan, Mr. M'Lennan, and Sir J. Lubbock, yet from the foregoing and
several other lines of evidence it seems probable (8.  Mr. C. Staniland
Wake argues strongly ('Anthropologia,' March, 1874, p. 197) against the
views held by these three writers on the former prevalence of almost
promiscuous intercourse; and he thinks that the classificatory system of
relationship can be otherwise explained.) that the habit of marriage, in
any strict sense of the word, has been gradually developed; and that almost
promiscuous or very loose intercourse was once extremely common throughout
the world.  Nevertheless, from the strength of the feeling of jealousy all
through the animal kingdom, as well as from the analogy of the lower
animals, more particularly of those which come nearest to man, I cannot
believe that absolutely promiscuous intercourse prevailed in times past,
shortly before man attained to his present rank in the zoological scale.
Man, as I have attempted to shew, is certainly descended from some ape-like
creature.  With the existing Quadrumana, as far as their habits are known,
the males of some species are monogamous, but live during only a part of
the year with the females:  of this the orang seems to afford an instance.
Several kinds, for example some of the Indian and American monkeys, are
strictly monogamous, and associate all the year round with their wives.
Others are polygamous, for example the gorilla and several American
species, and each family lives separate.  Even when this occurs, the
families inhabiting the same district are probably somewhat social; the
chimpanzee, for instance, is occasionally met with in large bands.  Again,
other species are polygamous, but several males, each with his own females,
live associated in a body, as with several species of baboons.  (9.  Brehm
('Thierleben,' B. i. p. 77) says Cynocephalus hamadryas lives in great
troops containing twice as many adult females as adult males.  See Rengger
on American polygamous species, and Owen ('Anatomy of Vertebrates,' vol.
iii. p. 746) on American monogamous species.  Other references might be
added.)  We may indeed conclude from what we know of the jealousy of all
male quadrupeds, armed, as many of them are, with special weapons for
battling with their rivals, that promiscuous intercourse in a state of
nature is extremely improbable.  The pairing may not last for life, but
only for each birth; yet if the males which are the strongest and best able
to defend or otherwise assist their females and young, were to select the
more attractive females, this would suffice for sexual selection.

Therefore, looking far enough back in the stream of time, and judging from
the social habits of man as he now exists, the most probable view is that
he aboriginally lived in small communities, each with a single wife, or if
powerful with several, whom he jealously guarded against all other men.  Or
he may not have been a social animal, and yet have lived with several
wives, like the gorilla; for all the natives "agree that but one adult male
is seen in a band; when the young male grows up, a contest takes place for
mastery, and the strongest, by killing and driving out the others,
establishes himself as the head of the community."  (10.  Dr. Savage, in
'Boston Journal of Natural History,' vol. v. 1845-47, p. 423.)  The younger
males, being thus expelled and wandering about, would, when at last
successful in finding a partner, prevent too close interbreeding within the
limits of the same family.

Although savages are now extremely licentious, and although communal
marriages may formerly have largely prevailed, yet many tribes practise
some form of marriage, but of a far more lax nature than that of civilised
nations.  Polygamy, as just stated, is almost universally followed by the
leading men in every tribe.  Nevertheless there are tribes, standing almost
at the bottom of the scale, which are strictly monogamous.  This is the
case with the Veddahs of Ceylon:  they have a saying, according to Sir J.
Lubbock (11.  'Prehistoric Times,' 1869, p. 424.), "that death alone can
separate husband and wife."  An intelligent Kandyan chief, of course a
polygamist, "was perfectly scandalised at the utter barbarism of living
with only one wife, and never parting until separated by death."  It was,
he said, "just like the Wanderoo monkeys."  Whether savages who now enter
into some form of marriage, either polygamous or monogamous, have retained
this habit from primeval times, or whether they have returned to some form
of marriage, after passing through a stage of promiscuous intercourse, I
will not pretend to conjecture.

INFANTICIDE.

This practice is now very common throughout the world, and there is reason
to believe that it prevailed much more extensively during former times.
(12.  Mr. M'Lennan, 'Primitive Marriage,' 1865.  See especially on exogamy
and infanticide, pp. 130, 138, 165.)  Barbarians find it difficult to
support themselves and their children, and it is a simple plan to kill
their infants.  In South America some tribes, according to Azara, formerly
destroyed so many infants of both sexes that they were on the point of
extinction.  In the Polynesian Islands women have been known to kill from
four or five, to even ten of their children; and Ellis could not find a
single woman who had not killed at least one.  In a village on the eastern
frontier of India Colonel MacCulloch found not a single female child.
Wherever infanticide (13.  Dr. Gerland ('Ueber das Aussterben der
Naturvoelker,' 1868) has collected much information on infanticide, see
especially ss. 27, 51, 54.  Azara ('Voyages,' etc., tom. ii. pp. 94, 116)
enters in detail on the motives.  See also M'Lennan (ibid. p. 139) for
cases in India.  In the former reprints of the 2nd edition of this book an
incorrect quotation from Sir G. Grey was unfortunately given in the above
passage and has now been removed from the text.) prevails the struggle for
existence will be in so far less severe, and all the members of the tribe
will have an almost equally good chance of rearing their few surviving
children.  In most cases a larger number of female than of male infants are
destroyed, for it is obvious that the latter are of more value to the
tribe, as they will, when grown up, aid in defending it, and can support
themselves.  But the trouble experienced by the women in rearing children,
their consequent loss of beauty, the higher estimation set on them when
few, and their happier fate, are assigned by the women themselves, and by
various observers, as additional motives for infanticide.

When, owing to female infanticide, the women of a tribe were few, the habit
of capturing wives from neighbouring tribes would naturally arise.  Sir J.
Lubbock, however, as we have seen, attributes the practice in chief part to
the former existence of communal marriage, and to the men having
consequently captured women from other tribes to hold as their sole
property.  Additional causes might be assigned, such as the communities
being very small, in which case, marriageable women would often be
deficient.  That the habit was most extensively practised during former
times, even by the ancestors of civilised nations, is clearly shewn by the
preservation of many curious customs and ceremonies, of which Mr. M'Lennan
has given an interesting account.  In our own marriages the "best man"
seems originally to have been the chief abettor of the bridegroom in the
act of capture.  Now as long as men habitually procured their wives through
violence and craft, they would have been glad to seize on any woman, and
would not have selected the more attractive ones.  But as soon as the
practice of procuring wives from a distinct tribe was effected through
barter, as now occurs in many places, the more attractive women would
generally have been purchased.  The incessant crossing, however, between
tribe and tribe, which necessarily follows from any form of this habit,
would tend to keep all the people inhabiting the same country nearly
uniform in character; and this would interfere with the power of sexual
selection in differentiating the tribes.

The scarcity of women, consequent on female infanticide, leads, also, to
another practice, that of polyandry, still common in several parts of the
world, and which formerly, as Mr. M'Lennan believes, prevailed almost
universally:  but this latter conclusion is doubted by Mr. Morgan and Sir
J. Lubbock.  (14.  'Primitive Marriage,' p. 208; Sir J. Lubbock, 'Origin of
Civilisation,' p. 100.  See also Mr. Morgan, loc. cit., on the former
prevalence of polyandry.)  Whenever two or more men are compelled to marry
one woman, it is certain that all the women of the tribe will get married,
and there will be no selection by the men of the more attractive women.
But under these circumstances the women no doubt will have the power of
choice, and will prefer the more attractive men.  Azara, for instance,
describes how carefully a Guana woman bargains for all sorts of privileges,
before accepting some one or more husbands; and the men in consequence take
unusual care of their personal appearance.  So amongst the Todas of India,
who practise polyandry, the girls can accept or refuse any man.  (15.
Azara, 'Voyages,' etc., tom. ii. pp. 92-95; Colonel Marshall, 'Amongst the
Todas,' p. 212.)  A very ugly man in these cases would perhaps altogether
fail in getting a wife, or get one later in life; but the handsomer men,
although more successful in obtaining wives, would not, as far as we can
see, leave more offspring to inherit their beauty than the less handsome
husbands of the same women.

EARLY BETROTHALS AND SLAVERY OF WOMEN.

With many savages it is the custom to betroth the females whilst mere
infants; and this would effectually prevent preference being exerted on
either side according to personal appearance.  But it would not prevent the
more attractive women from being afterwards stolen or taken by force from
their husbands by the more powerful men; and this often happens in
Australia, America, and elsewhere.  The same consequences with reference to
sexual selection would to a certain extent follow, when women are valued
almost solely as slaves or beasts of burden, as is the case with many
savages.  The men, however, at all times would prefer the handsomest slaves
according to their standard of beauty.

We thus see that several customs prevail with savages which must greatly
interfere with, or completely stop, the action of sexual selection.  On the
other hand, the conditions of life to which savages are exposed, and some
of their habits, are favourable to natural selection; and this comes into
play at the same time with sexual selection.  Savages are known to suffer
severely from recurrent famines; they do not increase their food by
artificial means; they rarely refrain from marriage (16.  Burchell says
('Travels in S. Africa,' vol. ii. 1824, p. 58), that among the wild nations
of Southern Africa, neither men nor women ever pass their lives in a state
of celibacy.  Azara ('Voyages dans l'Amerique Merid.' tom. ii. 1809, p. 21)
makes precisely the same remark in regard to the wild Indians of South
America.), and generally marry whilst young.  Consequently they must be
subjected to occasional hard struggles for existence, and the favoured
individuals will alone survive.

At a very early period, before man attained to his present rank in the
scale, many of his conditions would be different from what now obtains
amongst savages.  Judging from the analogy of the lower animals, he would
then either live with a single female, or be a polygamist.  The most
powerful and able males would succeed best in obtaining attractive females.
They would also succeed best in the general struggle for life, and in
defending their females, as well as their offspring, from enemies of all
kinds.  At this early period the ancestors of man would not be sufficiently
advanced in intellect to look forward to distant contingencies; they would
not foresee that the rearing of all their children, especially their female
children, would make the struggle for life severer for the tribe.  They
would be governed more by their instincts and less by their reason than are
savages at the present day.  They would not at that period have partially
lost one of the strongest of all instincts, common to all the lower
animals, namely the love of their young offspring; and consequently they
would not have practised female infanticide.  Women would not have been
thus rendered scarce, and polyandry would not have been practised; for
hardly any other cause, except the scarcity of women seems sufficient to
break down the natural and widely prevalent feeling of jealousy, and the
desire of each male to possess a female for himself.  Polyandry would be a
natural stepping-stone to communal marriages or almost promiscuous
intercourse; though the best authorities believe that this latter habit
preceded polyandry.  During primordial times there would be no early
betrothals, for this implies foresight.  Nor would women be valued merely
as useful slaves or beasts of burthen.  Both sexes, if the females as well
as the males were permitted to exert any choice, would choose their
partners not for mental charms, or property, or social position, but almost
solely from external appearance.  All the adults would marry or pair, and
all the offspring, as far as that was possible, would be reared; so that
the struggle for existence would be periodically excessively severe.  Thus
during these times all the conditions for sexual selection would have been
more favourable than at a later period, when man had advanced in his
intellectual powers but had retrograded in his instincts.  Therefore,
whatever influence sexual selection may have had in producing the
differences between the races of man, and between man and the higher
Quadrumana, this influence would have been more powerful at a remote period
than at the present day, though probably not yet wholly lost.

THE MANNER OF ACTION OF SEXUAL SELECTION WITH MANKIND.

With primeval man under the favourable conditions just stated, and with
those savages who at the present time enter into any marriage tie, sexual
selection has probably acted in the following manner, subject to greater or
less interference from female infanticide, early betrothals, etc.  The
strongest and most vigorous men--those who could best defend and hunt for
their families, who were provided with the best weapons and possessed the
most property, such as a large number of dogs or other animals,--would
succeed in rearing a greater average number of offspring than the weaker
and poorer members of the same tribes.  There can, also, be no doubt that
such men would generally be able to select the more attractive women.  At
present the chiefs of nearly every tribe throughout the world succeed in
obtaining more than one wife.  I hear from Mr. Mantell that, until
recently, almost every girl in New Zealand who was pretty, or promised to
be pretty, was tapu to some chief.  With the Kafirs, as Mr. C. Hamilton
states (17.  'Anthropological Review,' Jan. 1870, p. xvi.), "the chiefs
generally have the pick of the women for many miles round, and are most
persevering in establishing or confirming their privilege."  We have seen
that each race has its own style of beauty, and we know that it is natural
to man to admire each characteristic point in his domestic animals, dress,
ornaments, and personal appearance, when carried a little beyond the
average.  If then the several foregoing propositions be admitted, and I
cannot see that they are doubtful, it would be an inexplicable circumstance
if the selection of the more attractive women by the more powerful men of
each tribe, who would rear on an average a greater number of children, did
not after the lapse of many generations somewhat modify the character of
the tribe.

When a foreign breed of our domestic animals is introduced into a new
country, or when a native breed is long and carefully attended to, either
for use or ornament, it is found after several generations to have
undergone a greater or less amount of change whenever the means of
comparison exist.  This follows from unconscious selection during a long
series of generations--that is, the preservation of the most approved
individuals--without any wish or expectation of such a result on the part
of the breeder.  So again, if during many years two careful breeders rear
animals of the same family, and do not compare them together or with a
common standard, the animals are found to have become, to the surprise of
their owners, slightly different.  (18.  The 'Variation of Animals and
Plants under Domestication,' vol. ii. pp. 210-217.)  Each breeder has
impressed, as von Nathusius well expresses it, the character of his own
mind--his own taste and judgment--on his animals.  What reason, then, can
be assigned why similar results should not follow from the long-continued
selection of the most admired women by those men of each tribe who were
able to rear the greatest number of children?  This would be unconscious
selection, for an effect would be produced, independently of any wish or
expectation on the part of the men who preferred certain women to others.

Let us suppose the members of a tribe, practising some form of marriage, to
spread over an unoccupied continent, they would soon split up into distinct
hordes, separated from each other by various barriers, and still more
effectually by the incessant wars between all barbarous nations.  The
hordes would thus be exposed to slightly different conditions and habits of
life, and would sooner or later come to differ in some small degree.  As
soon as this occurred, each isolated tribe would form for itself a slightly
different standard of beauty (19.  An ingenious writer argues, from a
comparison of the pictures of Raphael, Rubens, and modern French artists,
that the idea of beauty is not absolutely the same even throughout Europe:
see the 'Lives of Haydn and Mozart,' by Bombet (otherwise M. Beyle),
English translation, p. 278.); and then unconscious selection would come
into action through the more powerful and leading men preferring certain
women to others.  Thus the differences between the tribes, at first very
slight, would gradually and inevitably be more or less increased.

With animals in a state of nature, many characters proper to the males,
such as size, strength, special weapons, courage and pugnacity, have been
acquired through the law of battle.  The semi-human progenitors of man,
like their allies the Quadrumana, will almost certainly have been thus
modified; and, as savages still fight for the possession of their women, a
similar process of selection has probably gone on in a greater or less
degree to the present day.  Other characters proper to the males of the
lower animals, such as bright colours and various ornaments, have been
acquired by the more attractive males having been preferred by the females.
There are, however, exceptional cases in which the males are the selectors,
instead of having been the selected.  We recognise such cases by the
females being more highly ornamented than the males,--their ornamental
characters having been transmitted exclusively or chiefly to their female
offspring.  One such case has been described in the order to which man
belongs, that of the Rhesus monkey.

Man is more powerful in body and mind than woman, and in the savage state
he keeps her in a far more abject state of bondage than does the male of
any other animal; therefore it is not surprising that he should have gained
the power of selection.  Women are everywhere conscious of the value of
their own beauty; and when they have the means, they take more delight in
decorating themselves with all sorts of ornaments than do men.  They borrow
the plumes of male birds, with which nature has decked this sex, in order
to charm the females.  As women have long been selected for beauty, it is
not surprising that some of their successive variations should have been
transmitted exclusively to the same sex; consequently that they should have
transmitted beauty in a somewhat higher degree to their female than to
their male offspring, and thus have become more beautiful, according to
general opinion, than men.  Women, however, certainly transmit most of
their characters, including some beauty, to their offspring of both sexes;
so that the continued preference by the men of each race for the more
attractive women, according to their standard of taste, will have tended to
modify in the same manner all the individuals of both sexes belonging to
the race.

With respect to the other form of sexual selection (which with the lower
animals is much the more common), namely, when the females are the
selectors, and accept only those males which excite or charm them most, we
have reason to believe that it formerly acted on our progenitors.  Man in
all probability owes his beard, and perhaps some other characters, to
inheritance from an ancient progenitor who thus gained his ornaments.  But
this form of selection may have occasionally acted during later times; for
in utterly barbarous tribes the women have more power in choosing,
rejecting, and tempting their lovers, or of afterwards changing their
husbands, than might have been expected.  As this is a point of some
importance, I will give in detail such evidence as I have been able to
collect.

Hearne describes how a woman in one of the tribes of Arctic America
repeatedly ran away from her husband and joined her lover; and with the
Charruas of S. America, according to Azara, divorce is quite optional.
Amongst the Abipones, a man on choosing a wife bargains with the parents
about the price.  But "it frequently happens that the girl rescinds what
has been agreed upon between the parents and the bridegroom, obstinately
rejecting the very mention of marriage."  She often runs away, hides
herself, and thus eludes the bridegroom.  Captain Musters who lived with
the Patagonians, says that their marriages are always settled by
inclination; "if the parents make a match contrary to the daughter's will,
she refuses and is never compelled to comply."  In Tierra del Fuego a young
man first obtains the consent of the parents by doing them some service,
and then he attempts to carry off the girl; "but if she is unwilling, she
hides herself in the woods until her admirer is heartily tired of looking
for her, and gives up the pursuit; but this seldom happens."  In the Fiji
Islands the man seizes on the woman whom he wishes for his wife by actual
or pretended force; but "on reaching the home of her abductor, should she
not approve of the match, she runs to some one who can protect her; if,
however, she is satisfied, the matter is settled forthwith."  With the
Kalmucks there is a regular race between the bride and bridegroom, the
former having a fair start; and Clarke "was assured that no instance occurs
of a girl being caught, unless she has a partiality to the pursuer."
Amongst the wild tribes of the Malay Archipelago there is also a racing
match; and it appears from M. Bourien's account, as Sir J. Lubbock remarks,
that "the race, 'is not to the swift, nor the battle to the strong,' but to
the young man who has the good fortune to please his intended bride."  A
similar custom, with the same result, prevails with the Koraks of North-
Eastern Asia.

Turning to Africa:  the Kafirs buy their wives, and girls are severely
beaten by their fathers if they will not accept a chosen husband; but it is
manifest from many facts given by the Rev. Mr. Shooter, that they have
considerable power of choice.  Thus very ugly, though rich men, have been
known to fail in getting wives.  The girls, before consenting to be
betrothed, compel the men to shew themselves off first in front and then
behind, and "exhibit their paces."  They have been known to propose to a
man, and they not rarely run away with a favoured lover.  So again, Mr.
Leslie, who was intimately acquainted with the Kafirs, says, "it is a
mistake to imagine that a girl is sold by her father in the same manner,
and with the same authority, with which he would dispose of a cow."
Amongst the degraded Bushmen of S. Africa, "when a girl has grown up to
womanhood without having been betrothed, which, however, does not often
happen, her lover must gain her approbation, as well as that of the
parents."  (20.  Azara, 'Voyages,' etc., tom. ii. p. 23.  Dobrizhoffer, 'An
Account of the Abipones,' vol. ii. 1822, p. 207.  Capt. Musters, in 'Proc.
R. Geograph. Soc.' vol. xv. p. 47.  Williams on the Fiji Islanders, as
quoted by Lubbock, 'Origin of Civilisation,' 1870, p. 79.  On the Fuegians,
King and Fitzroy, 'Voyages of the "Adventure" and "Beagle,"' vol. ii. 1839,
p. 182.  On the Kalmucks, quoted by M'Lennan, 'Primitive Marriage,' 1865,
p. 32.  On the Malays, Lubbock, ibid. p. 76.  The Rev. J. Shooter, 'On the
Kafirs of Natal,' 1857, pp. 52-60.  Mr. D. Leslie, 'Kafir Character and
Customs,' 1871, p. 4.  On the Bush-men, Burchell, 'Travels in S. Africa,'
ii. 1824, p. 59.  On the Koraks by McKennan, as quoted by Mr. Wake, in
'Anthropologia,' Oct. 1873, p. 75.)  Mr. Winwood Reade made inquiries for
me with respect to the negroes of Western Africa, and he informs me that
"the women, at least among the more intelligent Pagan tribes, have no
difficulty in getting the husbands whom they may desire, although it is
considered unwomanly to ask a man to marry them.  They are quite capable of
falling in love, and of forming tender, passionate, and faithful
attachments."  Additional cases could be given.

We thus see that with savages the women are not in quite so abject a state
in relation to marriage as has often been supposed.  They can tempt the men
whom they prefer, and can sometimes reject those whom they dislike, either
before or after marriage.  Preference on the part of the women, steadily
acting in any one direction, would ultimately affect the character of the
tribe; for the women would generally choose not merely the handsomest men,
according to their standard of taste, but those who were at the same time
best able to defend and support them.  Such well-endowed pairs would
commonly rear a larger number of offspring than the less favoured.  The
same result would obviously follow in a still more marked manner if there
was selection on both sides; that is, if the more attractive, and at the
same time more powerful men were to prefer, and were preferred by, the more
attractive women.  And this double form of selection seems actually to have
occurred, especially during the earlier periods of our long history.

We will now examine a little more closely some of the characters which
distinguish the several races of man from one another and from the lower
animals, namely, the greater or less deficiency of hair on the body, and
the colour of the skin.  We need say nothing about the great diversity in
the shape of the features and of the skull between the different races, as
we have seen in the last chapter how different is the standard of beauty in
these respects.  These characters will therefore probably have been acted
on through sexual selection; but we have no means of judging whether they
have been acted on chiefly from the male or female side.  The musical
faculties of man have likewise been already discussed.

ABSENCE OF HAIR ON THE BODY, AND ITS DEVELOPMENT ON THE FACE AND HEAD.

From the presence of the woolly hair or lanugo on the human foetus, and of
rudimentary hairs scattered over the body during maturity, we may infer
that man is descended from some animal which was born hairy and remained so
during life.  The loss of hair is an inconvenience and probably an injury
to man, even in a hot climate, for he is thus exposed to the scorching of
the sun, and to sudden chills, especially during wet weather.  As Mr.
Wallace remarks, the natives in all countries are glad to protect their
naked backs and shoulders with some slight covering.  No one supposes that
the nakedness of the skin is any direct advantage to man; his body
therefore cannot have been divested of hair through natural selection.
(21.  'Contributions to the Theory of Natural Selection,' 1870, p. 346.
Mr. Wallace believes (p. 350) "that some intelligent power has guided or
determined the development of man"; and he considers the hairless condition
of the skin as coming under this head.  The Rev. T.R. Stebbing, in
commenting on this view ('Transactions of Devonshire Association for
Science,' 1870) remarks, that had Mr. Wallace "employed his usual ingenuity
on the question of man's hairless skin, he might have seen the possibility
of its selection through its superior beauty or the health attaching to
superior cleanliness.")  Nor, as shewn in a former chapter, have we any
evidence that this can be due to the direct action of climate, or that it
is the result of correlated development.

The absence of hair on the body is to a certain extent a secondary sexual
character; for in all parts of the world women are less hairy than men.
Therefore we may reasonably suspect that this character has been gained
through sexual selection.  We know that the faces of several species of
monkeys, and large surfaces at the posterior end of the body of other
species, have been denuded of hair; and this we may safely attribute to
sexual selection, for these surfaces are not only vividly coloured, but
sometimes, as with the male mandrill and female rhesus, much more vividly
in the one sex than in the other, especially during the breeding-season.  I
am informed by Mr. Bartlett that, as these animals gradually reach
maturity, the naked surfaces grow larger compared with the size of their
bodies.  The hair, however, appears to have been removed, not for the sake
of nudity, but that the colour of the skin may be more fully displayed.  So
again with many birds, it appears as if the head and neck had been divested
of feathers through sexual selection, to exhibit the brightly-coloured
skin.

As the body in woman is less hairy than in man, and as this character is
common to all races, we may conclude that it was our female semi-human
ancestors who were first divested of hair, and that this occurred at an
extremely remote period before the several races had diverged from a common
stock.  Whilst our female ancestors were gradually acquiring this new
character of nudity, they must have transmitted it almost equally to their
offspring of both sexes whilst young; so that its transmission, as with the
ornaments of many mammals and birds, has not been limited either by sex or
age.  There is nothing surprising in a partial loss of hair having been
esteemed as an ornament by our ape-like progenitors, for we have seen that
innumerable strange characters have been thus esteemed by animals of all
kinds, and have consequently been gained through sexual selection.  Nor is
it surprising that a slightly injurious character should have been thus
acquired; for we know that this is the case with the plumes of certain
birds, and with the horns of certain stags.

The females of some of the anthropoid apes, as stated in a former chapter,
are somewhat less hairy on the under surface than the males; and here we
have what might have afforded a commencement for the process of denudation.
With respect to the completion of the process through sexual selection, it
is well to bear in mind the New Zealand proverb, "There is no woman for a
hairy man."  All who have seen photographs of the Siamese hairy family will
admit how ludicrously hideous is the opposite extreme of excessive
hairiness.  And the king of Siam had to bribe a man to marry the first
hairy woman in the family; and she transmitted this character to her young
offspring of both sexes.  (22.  The 'Variation of Animals and Plants under
Domestication,' vol. ii. 1868, p. 237.)

Some races are much more hairy than others, especially the males; but it
must not be assumed that the more hairy races, such as the European, have
retained their primordial condition more completely than the naked races,
such as the Kalmucks or Americans.  It is more probable that the hairiness
of the former is due to partial reversion; for characters which have been
at some former period long inherited are always apt to return.  We have
seen that idiots are often very hairy, and they are apt to revert in other
characters to a lower animal type.  It does not appear that a cold climate
has been influential in leading to this kind of reversion; excepting
perhaps with the negroes, who have been reared during several generations
in the United States (23.  'Investigations into Military and
Anthropological Statistics of American Soldiers,' by B.A. Gould, 1869, p.
568:--Observations were carefully made on the hairiness of 2129 black and
coloured soldiers, whilst they were bathing; and by looking to the
published table, "it is manifest at a glance that there is but little, if
any, difference between the white and the black races in this respect."  It
is, however, certain that negroes in their native and much hotter land of
Africa, have remarkably smooth bodies.  It should be particularly observed,
that both pure blacks and mulattoes were included in the above enumeration;
and this is an unfortunate circumstance, as in accordance with a principle,
the truth of which I have elsewhere proved, crossed races of man would be
eminently liable to revert to the primordial hairy character of their early
ape-like progenitors.), and possibly with the Ainos, who inhabit the
northern islands of the Japan archipelago.  But the laws of inheritance are
so complex that we can seldom understand their action.  If the greater
hairiness of certain races be the result of reversion, unchecked by any
form of selection, its extreme variability, even within the limits of the
same race, ceases to be remarkable.  (24.  Hardly any view advanced in this
work has met with so much disfavour (see for instance, Sprengel, 'Die
Fortschritte des Darwinismus,' 1874, p. 80) as the above explanation of the
loss of hair in mankind through sexual selection; but none of the opposed
arguments seem to me of much weight, in comparison with the facts shewing
that the nudity of the skin is to a certain extent a secondary sexual
character in man and in some of the Quadrumana.)

With respect to the beard in man, if we turn to our best guide, the
Quadrumana, we find beards equally developed in both sexes of many species,
but in some, either confined to the males, or more developed in them than
in the females.  From this fact and from the curious arrangement, as well
as the bright colours of the hair about the heads of many monkeys, it is
highly probable, as before explained, that the males first acquired their
beards through sexual selection as an ornament, transmitting them in most
cases, equally or nearly so, to their offspring of both sexes.  We know
from Eschricht (25.  'Ueber die Richtung der Haare am Menschlichen Koerper,'
in Mueller's 'Archiv. fuer Anat. und Phys.' 1837, s. 40.) that with mankind
the female as well as the male foetus is furnished with much hair on the
face, especially round the mouth; and this indicates that we are descended
from progenitors of whom both sexes were bearded.  It appears therefore at
first sight probable that man has retained his beard from a very early
period, whilst woman lost her beard at the same time that her body became
almost completely divested of hair.  Even the colour of our beards seems to
have been inherited from an ape-like progenitor; for when there is any
difference in tint between the hair of the head and the beard, the latter
is lighter coloured in all monkeys and in man.  In those Quadrumana in
which the male has a larger beard than that of the female, it is fully
developed only at maturity, just as with mankind; and it is possible that
only the later stages of development have been retained by man.  In
opposition to this view of the retention of the beard from an early period
is the fact of its great variability in different races, and even within
the same race; for this indicates reversion,--long lost characters being
very apt to vary on re-appearance.

Nor must we overlook the part which sexual selection may have played in
later times; for we know that with savages the men of the beardless races
take infinite pains in eradicating every hair from their faces as something
odious, whilst the men of the bearded races feel the greatest pride in
their beards.  The women, no doubt, participate in these feelings, and if
so sexual selection can hardly have failed to have effected something in
the course of later times.  It is also possible that the long-continued
habit of eradicating the hair may have produced an inherited effect.  Dr.
Brown-Sequard has shewn that if certain animals are operated on in a
particular manner, their offspring are affected.  Further evidence could be
given of the inheritance of the effects of mutilations; but a fact lately
ascertained by Mr. Salvin (26.  On the tail-feathers of Motmots,
'Proceedings of the Zoological Society,' 1873, p. 429.) has a more direct
bearing on the present question; for he has shewn that the motmots, which
are known habitually to bite off the barbs of the two central tail-
feathers, have the barbs of these feathers naturally somewhat reduced.
(27.  Mr. Sproat has suggested ('Scenes and Studies of Savage Life,' 1868,
p. 25) this same view.  Some distinguished ethnologists, amongst others M.
Gosse of Geneva, believe that artificial modifications of the skull tend to
be inherited.)  Nevertheless, with mankind the habit of eradicating the
beard and the hairs on the body would probably not have arisen until these
had already become by some means reduced.

It is difficult to form any judgment as to how the hair on the head became
developed to its present great length in many races.  Eschricht (28.
'Ueber die Richtung,' ibid. s. 40.) states that in the human foetus the
hair on the face during the fifth month is longer than that on the head;
and this indicates that our semi-human progenitors were not furnished with
long tresses, which must therefore have been a late acquisition.  This is
likewise indicated by the extraordinary difference in the length of the
hair in the different races; in the negro the hair forms a mere curly mat;
with us it is of great length, and with the American natives it not rarely
reaches to the ground.  Some species of Semnopithecus have their heads
covered with moderately long hair, and this probably serves as an ornament
and was acquired through sexual selection.  The same view may perhaps be
extended to mankind, for we know that long tresses are now and were
formerly much admired, as may be observed in the works of almost every
poet; St. Paul says, "if a woman have long hair, it is a glory to her;" and
we have seen that in North America a chief was elected solely from the
length of his hair.

COLOUR OF THE SKIN.

The best kind of evidence that in man the colour of the skin has been
modified through sexual selection is scanty; for in most races the sexes do
not differ in this respect, and only slightly, as we have seen, in others.
We know, however, from the many facts already given that the colour of the
skin is regarded by the men of all races as a highly important element in
their beauty; so that it is a character which would be likely to have been
modified through selection, as has occurred in innumerable instances with
the lower animals.  It seems at first sight a monstrous supposition that
the jet-blackness of the negro should have been gained through sexual
selection; but this view is supported by various analogies, and we know
that negroes admire their own colour.  With mammals, when the sexes differ
in colour, the male is often black or much darker than the female; and it
depends merely on the form of inheritance whether this or any other tint is
transmitted to both sexes or to one alone.  The resemblance to a negro in
miniature of Pithecia satanas with his jet black skin, white rolling
eyeballs, and hair parted on the top of the head, is almost ludicrous.

The colour of the face differs much more widely in the various kinds of
monkeys than it does in the races of man; and we have some reason to
believe that the red, blue, orange, almost white and black tints of their
skin, even when common to both sexes, as well as the bright colours of
their fur, and the ornamental tufts about the head, have all been acquired
through sexual selection.  As the order of development during growth,
generally indicates the order in which the characters of a species have
been developed and modified during previous generations; and as the newly-
born infants of the various races of man do not differ nearly as much in
colour as do the adults, although their bodies are as completely destitute
of hair, we have some slight evidence that the tints of the different races
were acquired at a period subsequent to the removal of the hair, which must
have occurred at a very early period in the history of man.

SUMMARY.

We may conclude that the greater size, strength, courage, pugnacity, and
energy of man, in comparison with woman, were acquired during primeval
times, and have subsequently been augmented, chiefly through the contests
of rival males for the possession of the females.  The greater intellectual
vigour and power of invention in man is probably due to natural selection,
combined with the inherited effects of habit, for the most able men will
have succeeded best in defending and providing for themselves and for their
wives and offspring.  As far as the extreme intricacy of the subject
permits us to judge, it appears that our male ape-like progenitors acquired
their beards as an ornament to charm or excite the opposite sex, and
transmitted them only to their male offspring.  The females apparently
first had their bodies denuded of hair, also as a sexual ornament; but they
transmitted this character almost equally to both sexes.  It is not
improbable that the females were modified in other respects for the same
purpose and by the same means; so that women have acquired sweeter voices
and become more beautiful than men.

It deserves attention that with mankind the conditions were in many
respects much more favourable for sexual selection, during a very early
period, when man had only just attained to the rank of manhood, than during
later times.  For he would then, as we may safely conclude, have been
guided more by his instinctive passions, and less by foresight or reason.
He would have jealously guarded his wife or wives.  He would not have
practised infanticide; nor valued his wives merely as useful slaves; nor
have been betrothed to them during infancy.  Hence we may infer that the
races of men were differentiated, as far as sexual selection is concerned,
in chief part at a very remote epoch; and this conclusion throws light on
the remarkable fact that at the most ancient period, of which we have not
as yet any record, the races of man had already come to differ nearly or
quite as much as they do at the present day.

The views here advanced, on the part which sexual selection has played in
the history of man, want scientific precision.  He who does not admit this
agency in the case of the lower animals, will disregard all that I have
written in the later chapters on man.  We cannot positively say that this
character, but not that, has been thus modified; it has, however, been
shewn that the races of man differ from each other and from their nearest
allies, in certain characters which are of no service to them in their
daily habits of life, and which it is extremely probable would have been
modified through sexual selection.  We have seen that with the lowest
savages the people of each tribe admire their own characteristic
qualities,--the shape of the head and face, the squareness of the cheek-
bones, the prominence or depression of the nose, the colour of the skin,
the length of the hair on the head, the absence of hair on the face and
body, or the presence of a great beard, and so forth.  Hence these and
other such points could hardly fail to be slowly and gradually exaggerated,
from the more powerful and able men in each tribe, who would succeed in
rearing the largest number of offspring, having selected during many
generations for their wives the most strongly characterised and therefore
most attractive women.  For my own part I conclude that of all the causes
which have led to the differences in external appearance between the races
of man, and to a certain extent between man and the lower animals, sexual
selection has been the most efficient.


CHAPTER XXI.

GENERAL SUMMARY AND CONCLUSION.

Main conclusion that man is descended from some lower form--Manner of
development--Genealogy of man--Intellectual and moral faculties--Sexual
Selection--Concluding remarks.

A brief summary will be sufficient to recall to the reader's mind the more
salient points in this work.  Many of the views which have been advanced
are highly speculative, and some no doubt will prove erroneous; but I have
in every case given the reasons which have led me to one view rather than
to another.  It seemed worth while to try how far the principle of
evolution would throw light on some of the more complex problems in the
natural history of man.  False facts are highly injurious to the progress
of science, for they often endure long; but false views, if supported by
some evidence, do little harm, for every one takes a salutary pleasure in
proving their falseness:  and when this is done, one path towards error is
closed and the road to truth is often at the same time opened.

The main conclusion here arrived at, and now held by many naturalists who
are well competent to form a sound judgment, is that man is descended from
some less highly organised form.  The grounds upon which this conclusion
rests will never be shaken, for the close similarity between man and the
lower animals in embryonic development, as well as in innumerable points of
structure and constitution, both of high and of the most trifling
importance,--the rudiments which he retains, and the abnormal reversions to
which he is occasionally liable,--are facts which cannot be disputed.  They
have long been known, but until recently they told us nothing with respect
to the origin of man.  Now when viewed by the light of our knowledge of the
whole organic world, their meaning is unmistakable.  The great principle of
evolution stands up clear and firm, when these groups or facts are
considered in connection with others, such as the mutual affinities of the
members of the same group, their geographical distribution in past and
present times, and their geological succession.  It is incredible that all
these facts should speak falsely.  He who is not content to look, like a
savage, at the phenomena of nature as disconnected, cannot any longer
believe that man is the work of a separate act of creation.  He will be
forced to admit that the close resemblance of the embryo of man to that,
for instance, of a dog--the construction of his skull, limbs and whole
frame on the same plan with that of other mammals, independently of the
uses to which the parts may be put--the occasional re-appearance of various
structures, for instance of several muscles, which man does not normally
possess, but which are common to the Quadrumana--and a crowd of analogous
facts--all point in the plainest manner to the conclusion that man is the
co-descendant with other mammals of a common progenitor.

We have seen that man incessantly presents individual differences in all
parts of his body and in his mental faculties.  These differences or
variations seem to be induced by the same general causes, and to obey the
same laws as with the lower animals.  In both cases similar laws of
inheritance prevail.  Man tends to increase at a greater rate than his
means of subsistence; consequently he is occasionally subjected to a severe
struggle for existence, and natural selection will have effected whatever
lies within its scope.  A succession of strongly-marked variations of a
similar nature is by no means requisite; slight fluctuating differences in
the individual suffice for the work of natural selection; not that we have
any reason to suppose that in the same species, all parts of the
organisation tend to vary to the same degree.  We may feel assured that the
inherited effects of the long-continued use or disuse of parts will have
done much in the same direction with natural selection.  Modifications
formerly of importance, though no longer of any special use, are long-
inherited.  When one part is modified, other parts change through the
principle of correlation, of which we have instances in many curious cases
of correlated monstrosities.  Something may be attributed to the direct and
definite action of the surrounding conditions of life, such as abundant
food, heat or moisture; and lastly, many characters of slight physiological
importance, some indeed of considerable importance, have been gained
through sexual selection.

No doubt man, as well as every other animal, presents structures, which
seem to our limited knowledge, not to be now of any service to him, nor to
have been so formerly, either for the general conditions of life, or in the
relations of one sex to the other.  Such structures cannot be accounted for
by any form of selection, or by the inherited effects of the use and disuse
of parts.  We know, however, that many strange and strongly-marked
peculiarities of structure occasionally appear in our domesticated
productions, and if their unknown causes were to act more uniformly, they
would probably become common to all the individuals of the species.  We may
hope hereafter to understand something about the causes of such occasional
modifications, especially through the study of monstrosities:  hence the
labours of experimentalists, such as those of M. Camille Dareste, are full
of promise for the future.  In general we can only say that the cause of
each slight variation and of each monstrosity lies much more in the
constitution of the organism, than in the nature of the surrounding
conditions; though new and changed conditions certainly play an important
part in exciting organic changes of many kinds.

Through the means just specified, aided perhaps by others as yet
undiscovered, man has been raised to his present state.  But since he
attained to the rank of manhood, he has diverged into distinct races, or as
they may be more fitly called, sub-species.  Some of these, such as the
Negro and European, are so distinct that, if specimens had been brought to
a naturalist without any further information, they would undoubtedly have
been considered by him as good and true species.  Nevertheless all the
races agree in so many unimportant details of structure and in so many
mental peculiarities that these can be accounted for only by inheritance
from a common progenitor; and a progenitor thus characterised would
probably deserve to rank as man.

It must not be supposed that the divergence of each race from the other
races, and of all from a common stock, can be traced back to any one pair
of progenitors.  On the contrary, at every stage in the process of
modification, all the individuals which were in any way better fitted for
their conditions of life, though in different degrees, would have survived
in greater numbers than the less well-fitted.  The process would have been
like that followed by man, when he does not intentionally select particular
individuals, but breeds from all the superior individuals, and neglects the
inferior.  He thus slowly but surely modifies his stock, and unconsciously
forms a new strain.  So with respect to modifications acquired
independently of selection, and due to variations arising from the nature
of the organism and the action of the surrounding conditions, or from
changed habits of life, no single pair will have been modified much more
than the other pairs inhabiting the same country, for all will have been
continually blended through free intercrossing.

By considering the embryological structure of man,--the homologies which he
presents with the lower animals,--the rudiments which he retains,--and the
reversions to which he is liable, we can partly recall in imagination the
former condition of our early progenitors; and can approximately place them
in their proper place in the zoological series.  We thus learn that man is
descended from a hairy, tailed quadruped, probably arboreal in its habits,
and an inhabitant of the Old World.  This creature, if its whole structure
had been examined by a naturalist, would have been classed amongst the
Quadrumana, as surely as the still more ancient progenitor of the Old and
New World monkeys.  The Quadrumana and all the higher mammals are probably
derived from an ancient marsupial animal, and this through a long line of
diversified forms, from some amphibian-like creature, and this again from
some fish-like animal.  In the dim obscurity of the past we can see that
the early progenitor of all the Vertebrata must have been an aquatic
animal, provided with branchiae, with the two sexes united in the same
individual, and with the most important organs of the body (such as the
brain and heart) imperfectly or not at all developed.  This animal seems to
have been more like the larvae of the existing marine Ascidians than any
other known form.

The high standard of our intellectual powers and moral disposition is the
greatest difficulty which presents itself, after we have been driven to
this conclusion on the origin of man.  But every one who admits the
principle of evolution, must see that the mental powers of the higher
animals, which are the same in kind with those of man, though so different
in degree, are capable of advancement.  Thus the interval between the
mental powers of one of the higher apes and of a fish, or between those of
an ant and scale-insect, is immense; yet their development does not offer
any special difficulty; for with our domesticated animals, the mental
faculties are certainly variable, and the variations are inherited.  No one
doubts that they are of the utmost importance to animals in a state of
nature.  Therefore the conditions are favourable for their development
through natural selection.  The same conclusion may be extended to man; the
intellect must have been all-important to him, even at a very remote
period, as enabling him to invent and use language, to make weapons, tools,
traps, etc., whereby with the aid of his social habits, he long ago became
the most dominant of all living creatures.

A great stride in the development of the intellect will have followed, as
soon as the half-art and half-instinct of language came into use; for the
continued use of language will have reacted on the brain and produced an
inherited effect; and this again will have reacted on the improvement of
language.  As Mr. Chauncey Wright (1.  'On the Limits of Natural
Selection,' in the 'North American Review,' Oct. 1870, p. 295.) has well
remarked, the largeness of the brain in man relatively to his body,
compared with the lower animals, may be attributed in chief part to the
early use of some simple form of language,--that wonderful engine which
affixes signs to all sorts of objects and qualities, and excites trains of
thought which would never arise from the mere impression of the senses, or
if they did arise could not be followed out.  The higher intellectual
powers of man, such as those of ratiocination, abstraction, self-
consciousness, etc., probably follow from the continued improvement and
exercise of the other mental faculties.

The development of the moral qualities is a more interesting problem.  The
foundation lies in the social instincts, including under this term the
family ties.  These instincts are highly complex, and in the case of the
lower animals give special tendencies towards certain definite actions; but
the more important elements are love, and the distinct emotion of sympathy.
Animals endowed with the social instincts take pleasure in one another's
company, warn one another of danger, defend and aid one another in many
ways.  These instincts do not extend to all the individuals of the species,
but only to those of the same community.  As they are highly beneficial to
the species, they have in all probability been acquired through natural
selection.

A moral being is one who is capable of reflecting on his past actions and
their motives--of approving of some and disapproving of others; and the
fact that man is the one being who certainly deserves this designation, is
the greatest of all distinctions between him and the lower animals.  But in
the fourth chapter I have endeavoured to shew that the moral sense follows,
firstly, from the enduring and ever-present nature of the social instincts;
secondly, from man's appreciation of the approbation and disapprobation of
his fellows; and thirdly, from the high activity of his mental faculties,
with past impressions extremely vivid; and in these latter respects he
differs from the lower animals.  Owing to this condition of mind, man
cannot avoid looking both backwards and forwards, and comparing past
impressions.  Hence after some temporary desire or passion has mastered his
social instincts, he reflects and compares the now weakened impression of
such past impulses with the ever-present social instincts; and he then
feels that sense of dissatisfaction which all unsatisfied instincts leave
behind them, he therefore resolves to act differently for the future,--and
this is conscience.  Any instinct, permanently stronger or more enduring
than another, gives rise to a feeling which we express by saying that it
ought to be obeyed.  A pointer dog, if able to reflect on his past conduct,
would say to himself, I ought (as indeed we say of him) to have pointed at
that hare and not have yielded to the passing temptation of hunting it.

Social animals are impelled partly by a wish to aid the members of their
community in a general manner, but more commonly to perform certain
definite actions.  Man is impelled by the same general wish to aid his
fellows; but has few or no special instincts.  He differs also from the
lower animals in the power of expressing his desires by words, which thus
become a guide to the aid required and bestowed.  The motive to give aid is
likewise much modified in man:  it no longer consists solely of a blind
instinctive impulse, but is much influenced by the praise or blame of his
fellows.  The appreciation and the bestowal of praise and blame both rest
on sympathy; and this emotion, as we have seen, is one of the most
important elements of the social instincts.  Sympathy, though gained as an
instinct, is also much strengthened by exercise or habit.  As all men
desire their own happiness, praise or blame is bestowed on actions and
motives, according as they lead to this end; and as happiness is an
essential part of the general good, the greatest-happinesss principle
indirectly serves as a nearly safe standard of right and wrong.  As the
reasoning powers advance and experience is gained, the remoter effects of
certain lines of conduct on the character of the individual, and on the
general good, are perceived; and then the self-regarding virtues come
within the scope of public opinion, and receive praise, and their opposites
blame.  But with the less civilised nations reason often errs, and many bad
customs and base superstitions come within the same scope, and are then
esteemed as high virtues, and their breach as heavy crimes.

The moral faculties are generally and justly esteemed as of higher value
than the intellectual powers.  But we should bear in mind that the activity
of the mind in vividly recalling past impressions is one of the fundamental
though secondary bases of conscience.  This affords the strongest argument
for educating and stimulating in all possible ways the intellectual
faculties of every human being.  No doubt a man with a torpid mind, if his
social affections and sympathies are well developed, will be led to good
actions, and may have a fairly sensitive conscience.  But whatever renders
the imagination more vivid and strengthens the habit of recalling and
comparing past impressions, will make the conscience more sensitive, and
may even somewhat compensate for weak social affections and sympathies.

The moral nature of man has reached its present standard, partly through
the advancement of his reasoning powers and consequently of a just public
opinion, but especially from his sympathies having been rendered more
tender and widely diffused through the effects of habit, example,
instruction, and reflection.  It is not improbable that after long practice
virtuous tendencies may be inherited.  With the more civilised races, the
conviction of the existence of an all-seeing Deity has had a potent
influence on the advance of morality.  Ultimately man does not accept the
praise or blame of his fellows as his sole guide, though few escape this
influence, but his habitual convictions, controlled by reason, afford him
the safest rule.  His conscience then becomes the supreme judge and
monitor.  Nevertheless the first foundation or origin of the moral sense
lies in the social instincts, including sympathy; and these instincts no
doubt were primarily gained, as in the case of the lower animals, through
natural selection.

The belief in God has often been advanced as not only the greatest, but the
most complete of all the distinctions between man and the lower animals.
It is however impossible, as we have seen, to maintain that this belief is
innate or instinctive in man.  On the other hand a belief in all-pervading
spiritual agencies seems to be universal; and apparently follows from a
considerable advance in man's reason, and from a still greater advance in
his faculties of imagination, curiosity and wonder.  I am aware that the
assumed instinctive belief in God has been used by many persons as an
argument for His existence.  But this is a rash argument, as we should thus
be compelled to believe in the existence of many cruel and malignant
spirits, only a little more powerful than man; for the belief in them is
far more general than in a beneficent Deity.  The idea of a universal and
beneficent Creator does not seem to arise in the mind of man, until he has
been elevated by long-continued culture.

He who believes in the advancement of man from some low organised form,
will naturally ask how does this bear on the belief in the immortality of
the soul.  The barbarous races of man, as Sir J. Lubbock has shewn, possess
no clear belief of this kind; but arguments derived from the primeval
beliefs of savages are, as we have just seen, of little or no avail.  Few
persons feel any anxiety from the impossibility of determining at what
precise period in the development of the individual, from the first trace
of a minute germinal vesicle, man becomes an immortal being; and there is
no greater cause for anxiety because the period cannot possibly be
determined in the gradually ascending organic scale.  (2.  The Rev. J.A.
Picton gives a discussion to this effect in his 'New Theories and the Old
Faith,' 1870.)

I am aware that the conclusions arrived at in this work will be denounced
by some as highly irreligious; but he who denounces them is bound to shew
why it is more irreligious to explain the origin of man as a distinct
species by descent from some lower form, through the laws of variation and
natural selection, than to explain the birth of the individual through the
laws of ordinary reproduction.  The birth both of the species and of the
individual are equally parts of that grand sequence of events, which our
minds refuse to accept as the result of blind chance.  The understanding
revolts at such a conclusion, whether or not we are able to believe that
every slight variation of structure,--the union of each pair in marriage,
the dissemination of each seed,--and other such events, have all been
ordained for some special purpose.

Sexual selection has been treated at great length in this work; for, as I
have attempted to shew, it has played an important part in the history of
the organic world.  I am aware that much remains doubtful, but I have
endeavoured to give a fair view of the whole case.  In the lower divisions
of the animal kingdom, sexual selection seems to have done nothing:  such
animals are often affixed for life to the same spot, or have the sexes
combined in the same individual, or what is still more important, their
perceptive and intellectual faculties are not sufficiently advanced to
allow of the feelings of love and jealousy, or of the exertion of choice.
When, however, we come to the Arthropoda and Vertebrata, even to the lowest
classes in these two great Sub-Kingdoms, sexual selection has effected
much.

In the several great classes of the animal kingdom,--in mammals, birds,
reptiles, fishes, insects, and even crustaceans,--the differences between
the sexes follow nearly the same rules.  The males are almost always the
wooers; and they alone are armed with special weapons for fighting with
their rivals.  They are generally stronger and larger than the females, and
are endowed with the requisite qualities of courage and pugnacity.  They
are provided, either exclusively or in a much higher degree than the
females, with organs for vocal or instrumental music, and with odoriferous
glands.  They are ornamented with infinitely diversified appendages, and
with the most brilliant or conspicuous colours, often arranged in elegant
patterns, whilst the females are unadorned.  When the sexes differ in more
important structures, it is the male which is provided with special sense-
organs for discovering the female, with locomotive organs for reaching her,
and often with prehensile organs for holding her.  These various structures
for charming or securing the female are often developed in the male during
only part of the year, namely the breeding-season.  They have in many cases
been more or less transferred to the females; and in the latter case they
often appear in her as mere rudiments.  They are lost or never gained by
the males after emasculation.  Generally they are not developed in the male
during early youth, but appear a short time before the age for
reproduction.  Hence in most cases the young of both sexes resemble each
other; and the female somewhat resembles her young offspring throughout
life.  In almost every great class a few anomalous cases occur, where there
has been an almost complete transposition of the characters proper to the
two sexes; the females assuming characters which properly belong to the
males.  This surprising uniformity in the laws regulating the differences
between the sexes in so many and such widely separated classes, is
intelligible if we admit the action of one common cause, namely sexual
selection.

Sexual selection depends on the success of certain individuals over others
of the same sex, in relation to the propagation of the species; whilst
natural selection depends on the success of both sexes, at all ages, in
relation to the general conditions of life.  The sexual struggle is of two
kinds; in the one it is between individuals of the same sex, generally the
males, in order to drive away or kill their rivals, the females remaining
passive; whilst in the other, the struggle is likewise between the
individuals of the same sex, in order to excite or charm those of the
opposite sex, generally the females, which no longer remain passive, but
select the more agreeable partners.  This latter kind of selection is
closely analogous to that which man unintentionally, yet effectually,
brings to bear on his domesticated productions, when he preserves during a
long period the most pleasing or useful individuals, without any wish to
modify the breed.

The laws of inheritance determine whether characters gained through sexual
selection by either sex shall be transmitted to the same sex, or to both;
as well as the age at which they shall be developed.  It appears that
variations arising late in life are commonly transmitted to one and the
same sex.  Variability is the necessary basis for the action of selection,
and is wholly independent of it.  It follows from this, that variations of
the same general nature have often been taken advantage of and accumulated
through sexual selection in relation to the propagation of the species, as
well as through natural selection in relation to the general purposes of
life.  Hence secondary sexual characters, when equally transmitted to both
sexes can be distinguished from ordinary specific characters only by the
light of analogy.  The modifications acquired through sexual selection are
often so strongly pronounced that the two sexes have frequently been ranked
as distinct species, or even as distinct genera.  Such strongly-marked
differences must be in some manner highly important; and we know that they
have been acquired in some instances at the cost not only of inconvenience,
but of exposure to actual danger.

The belief in the power of sexual selection rests chiefly on the following
considerations.  Certain characters are confined to one sex; and this alone
renders it probable that in most cases they are connected with the act of
reproduction.  In innumerable instances these characters are fully
developed only at maturity, and often during only a part of the year, which
is always the breeding-season.  The males (passing over a few exceptional
cases) are the more active in courtship; they are the better armed, and are
rendered the more attractive in various ways.  It is to be especially
observed that the males display their attractions with elaborate care in
the presence of the females; and that they rarely or never display them
excepting during the season of love.  It is incredible that all this should
be purposeless.  Lastly we have distinct evidence with some quadrupeds and
birds, that the individuals of one sex are capable of feeling a strong
antipathy or preference for certain individuals of the other sex.

Bearing in mind these facts, and the marked results of man's unconscious
selection, when applied to domesticated animals and cultivated plants, it
seems to me almost certain that if the individuals of one sex were during a
long series of generations to prefer pairing with certain individuals of
the other sex, characterised in some peculiar manner, the offspring would
slowly but surely become modified in this same manner.  I have not
attempted to conceal that, excepting when the males are more numerous than
the females, or when polygamy prevails, it is doubtful how the more
attractive males succeed in leaving a large number of offspring to inherit
their superiority in ornaments or other charms than the less attractive
males; but I have shewn that this would probably follow from the females,--
especially the more vigorous ones, which would be the first to breed,--
preferring not only the more attractive but at the same time the more
vigorous and victorious males.

Although we have some positive evidence that birds appreciate bright and
beautiful objects, as with the bower-birds of Australia, and although they
certainly appreciate the power of song, yet I fully admit that it is
astonishing that the females of many birds and some mammals should be
endowed with sufficient taste to appreciate ornaments, which we have reason
to attribute to sexual selection; and this is even more astonishing in the
case of reptiles, fish, and insects.  But we really know little about the
minds of the lower animals.  It cannot be supposed, for instance, that male
birds of paradise or peacocks should take such pains in erecting,
spreading, and vibrating their beautiful plumes before the females for no
purpose.  We should remember the fact given on excellent authority in a
former chapter, that several peahens, when debarred from an admired male,
remained widows during a whole season rather than pair with another bird.

Nevertheless I know of no fact in natural history more wonderful than that
the female Argus pheasant should appreciate the exquisite shading of the
ball-and-socket ornaments and the elegant patterns on the wing-feather of
the male.  He who thinks that the male was created as he now exists must
admit that the great plumes, which prevent the wings from being used for
flight, and which are displayed during courtship and at no other time in a
manner quite peculiar to this one species, were given to him as an
ornament.  If so, he must likewise admit that the female was created and
endowed with the capacity of appreciating such ornaments.  I differ only in
the conviction that the male Argus pheasant acquired his beauty gradually,
through the preference of the females during many generations for the more
highly ornamented males; the aesthetic capacity of the females having been
advanced through exercise or habit, just as our own taste is gradually
improved.  In the male through the fortunate chance of a few feathers being
left unchanged, we can distinctly trace how simple spots with a little
fulvous shading on one side may have been developed by small steps into the
wonderful ball-and-socket ornaments; and it is probable that they were
actually thus developed.

Everyone who admits the principle of evolution, and yet feels great
difficulty in admitting that female mammals, birds, reptiles, and fish,
could have acquired the high taste implied by the beauty of the males, and
which generally coincides with our own standard, should reflect that the
nerve-cells of the brain in the highest as well as in the lowest members of
the Vertebrate series, are derived from those of the common progenitor of
this great Kingdom.  For we can thus see how it has come to pass that
certain mental faculties, in various and widely distinct groups of animals,
have been developed in nearly the same manner and to nearly the same
degree.

The reader who has taken the trouble to go through the several chapters
devoted to sexual selection, will be able to judge how far the conclusions
at which I have arrived are supported by sufficient evidence.  If he
accepts these conclusions he may, I think, safely extend them to mankind;
but it would be superfluous here to repeat what I have so lately said on
the manner in which sexual selection apparently has acted on man, both on
the male and female side, causing the two sexes to differ in body and mind,
and the several races to differ from each other in various characters, as
well as from their ancient and lowly-organised progenitors.

He who admits the principle of sexual selection will be led to the
remarkable conclusion that the nervous system not only regulates most of
the existing functions of the body, but has indirectly influenced the
progressive development of various bodily structures and of certain mental
qualities.  Courage, pugnacity, perseverance, strength and size of body,
weapons of all kinds, musical organs, both vocal and instrumental, bright
colours and ornamental appendages, have all been indirectly gained by the
one sex or the other, through the exertion of choice, the influence of love
and jealousy, and the appreciation of the beautiful in sound, colour or
form; and these powers of the mind manifestly depend on the development of
the brain.

Man scans with scrupulous care the character and pedigree of his horses,
cattle, and dogs before he matches them; but when he comes to his own
marriage he rarely, or never, takes any such care.  He is impelled by
nearly the same motives as the lower animals, when they are left to their
own free choice, though he is in so far superior to them that he highly
values mental charms and virtues.  On the other hand he is strongly
attracted by mere wealth or rank.  Yet he might by selection do something
not only for the bodily constitution and frame of his offspring, but for
their intellectual and moral qualities.  Both sexes ought to refrain from
marriage if they are in any marked degree inferior in body or mind; but
such hopes are Utopian and will never be even partially realised until the
laws of inheritance are thoroughly known.  Everyone does good service, who
aids towards this end.  When the principles of breeding and inheritance are
better understood, we shall not hear ignorant members of our legislature
rejecting with scorn a plan for ascertaining whether or not consanguineous
marriages are injurious to man.

The advancement of the welfare of mankind is a most intricate problem:  all
ought to refrain from marriage who cannot avoid abject poverty for their
children; for poverty is not only a great evil, but tends to its own
increase by leading to recklessness in marriage.  On the other hand, as Mr.
Galton has remarked, if the prudent avoid marriage, whilst the reckless
marry, the inferior members tend to supplant the better members of society.
Man, like every other animal, has no doubt advanced to his present high
condition through a struggle for existence consequent on his rapid
multiplication; and if he is to advance still higher, it is to be feared
that he must remain subject to a severe struggle.  Otherwise he would sink
into indolence, and the more gifted men would not be more successful in the
battle of life than the less gifted.  Hence our natural rate of increase,
though leading to many and obvious evils, must not be greatly diminished by
any means.  There should be open competition for all men; and the most able
should not be prevented by laws or customs from succeeding best and rearing
the largest number of offspring.  Important as the struggle for existence
has been and even still is, yet as far as the highest part of man's nature
is concerned there are other agencies more important.  For the moral
qualities are advanced, either directly or indirectly, much more through
the effects of habit, the reasoning powers, instruction, religion, etc.,
than through natural selection; though to this latter agency may be safely
attributed the social instincts, which afforded the basis for the
development of the moral sense.

The main conclusion arrived at in this work, namely, that man is descended
from some lowly organised form, will, I regret to think, be highly
distasteful to many.  But there can hardly be a doubt that we are descended
from barbarians.  The astonishment which I felt on first seeing a party of
Fuegians on a wild and broken shore will never be forgotten by me, for the
reflection at once rushed into my mind--such were our ancestors.  These men
were absolutely naked and bedaubed with paint, their long hair was tangled,
their mouths frothed with excitement, and their expression was wild,
startled, and distrustful.  They possessed hardly any arts, and like wild
animals lived on what they could catch; they had no government, and were
merciless to every one not of their own small tribe.  He who has seen a
savage in his native land will not feel much shame, if forced to
acknowledge that the blood of some more humble creature flows in his veins.
For my own part I would as soon be descended from that heroic little
monkey, who braved his dreaded enemy in order to save the life of his
keeper, or from that old baboon, who descending from the mountains, carried
away in triumph his young comrade from a crowd of astonished dogs--as from
a savage who delights to torture his enemies, offers up bloody sacrifices,
practices infanticide without remorse, treats his wives like slaves, knows
no decency, and is haunted by the grossest superstitions.

Man may be excused for feeling some pride at having risen, though not
through his own exertions, to the very summit of the organic scale; and the
fact of his having thus risen, instead of having been aboriginally placed
there, may give him hope for a still higher destiny in the distant future.
But we are not here concerned with hopes or fears, only with the truth as
far as our reason permits us to discover it; and I have given the evidence
to the best of my ability.  We must, however, acknowledge, as it seems to
me, that man with all his noble qualities, with sympathy which feels for
the most debased, with benevolence which extends not only to other men but
to the humblest living creature, with his god-like intellect which has
penetrated into the movements and constitution of the solar system--with
all these exalted powers--Man still bears in his bodily frame the indelible
stamp of his lowly origin.


SUPPLEMENTAL NOTE.

ON SEXUAL SELECTION IN RELATION TO MONKEYS.

Reprinted from NATURE, November 2, 1876, p. 18.

In the discussion on Sexual Selection in my 'Descent of Man,' no case
interested and perplexed me so much as the brightly-coloured hinder ends
and adjoining parts of certain monkeys.  As these parts are more brightly
coloured in one sex than the other, and as they become more brilliant
during the season of love, I concluded that the colours had been gained as
a sexual attraction.  I was well aware that I thus laid myself open to
ridicule; though in fact it is not more surprising that a monkey should
display his bright-red hinder end than that a peacock should display his
magnificent tail.  I had, however, at that time no evidence of monkeys
exhibiting this part of their bodies during their courtship; and such
display in the case of birds affords the best evidence that the ornaments
of the males are of service to them by attracting or exciting the females.
I have lately read an article by Joh. von Fischer, of Gotha, published in
'Der Zoologische Garten,' April 1876, on the expression of monkeys under
various emotions, which is well worthy of study by any one interested in
the subject, and which shews that the author is a careful and acute
observer.  In this article there is an account of the behaviour of a young
male mandrill when he first beheld himself in a looking-glass, and it is
added, that after a time he turned round and presented his red hinder end
to the glass.  Accordingly I wrote to Herr J. von Fischer to ask what he
supposed was the meaning of this strange action, and he has sent me two
long letters full of new and curious details, which will, I hope, be
hereafter published.  He says that he was himself at first perplexed by the
above action, and was thus led carefully to observe several individuals of
various other species of monkeys, which he has long kept in his house.  He
finds that not only the mandrill (Cynocephalus mormon) but the drill (C.
leucophaeus) and three other kinds of baboons (C. hamadryas, sphinx, and
babouin), also Cynopithecus niger, and Macacus rhesus and nemestrinus, turn
this part of their bodies, which in all these species is more or less
brightly coloured, to him when they are pleased, and to other persons as a
sort of greeting.  He took pains to cure a Macacus rhesus, which he had
kept for five years, of this indecorous habit, and at last succeeded.
These monkeys are particularly apt to act in this manner, grinning at the
same time, when first introduced to a new monkey, but often also to their
old monkey friends; and after this mutual display they begin to play
together.  The young mandrill ceased spontaneously after a time to act in
this manner towards his master, von Fischer, but continued to do so towards
persons who were strangers and to new monkeys.  A young Cynopithecus niger
never acted, excepting on one occasion, in this way towards his master, but
frequently towards strangers, and continues to do so up to the present
time.  From these facts Von Fischer concludes that the monkeys which
behaved in this manner before a looking-glass (viz., the mandrill, drill,
Cynopithecus niger, Macacus rhesus and nemestrinus) acted as if their
reflection were a new acquaintance.  The mandrill and drill, which have
their hinder ends especially ornamented, display it even whilst quite
young, more frequently and more ostentatiously than do the other kinds.
Next in order comes Cynocephalus hamadryas, whilst the other species act in
this manner seldomer.  The individuals, however, of the same species vary
in this respect, and some which were very shy never displayed their hinder
ends.  It deserves especial attention that Von Fischer has never seen any
species purposely exhibit the hinder part of its body, if not at all
coloured.  This remark applies to many individuals of Macacus cynomolgus
and Cercocebus radiatus (which is closely allied to M. rhesus), to three
species of Cercopithecus and several American monkeys.  The habit of
turning the hinder ends as a greeting to an old friend or new acquaintance,
which seems to us so odd, is not really more so than the habits of many
savages, for instance that of rubbing their bellies with their hands, or
rubbing noses together.  The habit with the mandrill and drill seems to be
instinctive or inherited, as it was followed by very young animals; but it
is modified or guided, like so many other instincts, by observation, for
Von Fischer says that they take pains to make their display fully; and if
made before two observers, they turn to him who seems to pay the most
attention.

With respect to the origin of the habit, Von Fischer remarks that his
monkeys like to have their naked hinder ends patted or stroked, and that
they then grunt with pleasure.  They often also turn this part of their
bodies to other monkeys to have bits of dirt picked off, and so no doubt it
would be with respect to thorns.  But the habit with adult animals is
connected to a certain extent with sexual feelings, for Von Fischer watched
through a glass door a female Cynopithecus niger, and she during several
days, "umdrehte und dem Maennchen mit gurgelnden Toenen die stark geroethete
Sitzflache zeigte, was ich frueher nie an diesem Thier bemerkt hatte.  Beim
Anblick dieses Gegenstandes erregte sich das Maennchen sichtlich, denn es
polterte heftig an den Staeben, ebenfalls gurgelnde Laute ausstossend."  As
all the monkeys which have the hinder parts of their bodies more or less
brightly coloured live, according to Von Fischer, in open rocky places, he
thinks that these colours serve to render one sex conspicuous at a distance
to the other; but, as monkeys are such gregarious animals, I should have
thought that there was no need for the sexes to recognise each other at a
distance.  It seems to me more probable that the bright colours, whether on
the face or hinder end, or, as in the mandrill, on both, serve as a sexual
ornament and attraction.  Anyhow, as we now know that monkeys have the
habit of turning their hinder ends towards other monkeys, it ceases to be
at all surprising that it should have been this part of their bodies which
has been more or less decorated.  The fact that it is only the monkeys thus
characterised which, as far as at present known, act in this manner as a
greeting towards other monkeys renders it doubtful whether the habit was
first acquired from some independent cause, and that afterwards the parts
in question were coloured as a sexual ornament; or whether the colouring
and the habit of turning round were first acquired through variation and
sexual selection, and that afterwards the habit was retained as a sign of
pleasure or as a greeting, through the principle of inherited association.
This principle apparently comes into play on many occasions:  thus it is
generally admitted that the songs of birds serve mainly as an attraction
during the season of love, and that the leks, or great congregations of the
black-grouse, are connected with their courtship; but the habit of singing
has been retained by some birds when they feel happy, for instance by the
common robin, and the habit of congregating has been retained by the black-
grouse during other seasons of the year.

I beg leave to refer to one other point in relation to sexual selection.
It has been objected that this form of selection, as far as the ornaments
of the males are concerned, implies that all females within the same
district must possess and exercise exactly the same taste.  It should,
however, be observed, in the first place, that although the range of
variation of a species may be very large, it is by no means indefinite.  I
have elsewhere given a good instance of this fact in the pigeon, of which
there are at least a hundred varieties differing widely in their colours,
and at least a score of varieties of the fowl differing in the same kind of
way; but the range of colour in these two species is extremely distinct.
Therefore the females of natural species cannot have an unlimited scope for
their taste.  In the second place, I presume that no supporter of the
principle of sexual selection believes that the females select particular
points of beauty in the males; they are merely excited or attracted in a
greater degree by one male than by another, and this seems often to depend,
especially with birds, on brilliant colouring.  Even man, excepting perhaps
an artist, does not analyse the slight differences in the features of the
woman whom he may admire, on which her beauty depends.  The male mandrill
has not only the hinder end of his body, but his face gorgeously coloured
and marked with oblique ridges, a yellow beard, and other ornaments.  We
may infer from what we see of the variation of animals under domestication,
that the above several ornaments of the mandrill were gradually acquired by
one individual varying a little in one way, and another individual in
another way.  The males which were the handsomest or the most attractive in
any manner to the females would pair oftenest, and would leave rather more
offspring than other males.  The offspring of the former, although
variously intercrossed, would either inherit the peculiarities of their
fathers or transmit an increased tendency to vary in the same manner.
Consequently the whole body of males inhabiting the same country would tend
from the effects of constant intercrossing to become modified almost
uniformly, but sometimes a little more in one character and sometimes in
another, though at an extremely slow rate; all ultimately being thus
rendered more attractive to the females.  The process is like that which I
have called unconscious selection by man, and of which I have given several
instances.  In one country the inhabitants value a fleet or light dog or
horse, and in another country a heavier and more powerful one; in neither
country is there any selection of individual animals with lighter or
stronger bodies and limbs; nevertheless after a considerable lapse of time
the individuals are found to have been modified in the desired manner
almost uniformly, though differently in each country.  In two absolutely
distinct countries inhabited by the same species, the individuals of which
can never during long ages have intermigrated and intercrossed, and where,
moreover, the variations will probably not have been identically the same,
sexual selection might cause the males to differ.  Nor does the belief
appear to me altogether fanciful that two sets of females, surrounded by a
very different environment, would be apt to acquire somewhat different
tastes with respect to form, sound, or colour.  However this may be, I have
given in my 'Descent of Man' instances of closely-allied birds inhabiting
distinct countries, of which the young and the females cannot be
distinguished, whilst the adult males differ considerably, and this may be
attributed with much probability to the action of sexual selection.
During the summer of 1860, I was surprised by finding how large a
number of insects were caught by the leaves of the common sun-dew
(Drosera rotundifolia) on a heath in Sussex. I had heard that insects
were thus caught, but knew nothing further on the subject.* I

* As Dr. Nitschke has given ('Bot. Zeitung,' 1860, p. 229) the
bibliography of Drosera, I need not here go into details. Most of the
notices published before 1860 are brief and unimportant.  The oldest
paper seems to have been one of the most valuable, namely, by Dr. Roth,
in 1782.  There is also an interesting though short account of the
habits of Drosera by Dr. Milde, in the 'Bot. Zeitung,' 1852, p. 540. In
1855, in the 'Annales des Sc. nat. bot.' tom. iii. pp. 297 and 304, MM.
Groenland and Trcul each published papers, with figures, on the
structure of the leaves; but M. Trcul went so far as to doubt whether
they possessed any power of movement. Dr. Nitschke's papers in the
'Bot. Zeitung' for 1860 and 1861 are by far the most important ones
which have been published, both on the habits and structure of this
plant; and I shall frequently have occasion to quote from them. His
discussions on several points, for instance on the transmission of an
excitement from one part of the leaf to another, are excellent. On
December 11, 1862, Mr. J. Scott read a paper before the Botanical
Society of Edinburgh, [[page 2]] which was published in the 'Gardeners'
Chronicle,' 1863, p. 30. Mr. Scott shows that gentle irritation of the
hairs, as well as insects placed on the disc of the leaf, cause the
hairs to bend inwards. Mr. A.W. Bennett also gave another interesting
account of the movements of the leaves before the British Association
for 1873. In this same year Dr. Warming published an essay, in which he
describes the structure of the so-called hairs, entitled, "Sur la
Diffrence entre les Trichomes," &c., extracted from the proceedings of
the Soc. d'Hist. Nat. de Copenhague. I shall also have occasion
hereafter to refer to a paper by Mrs. Treat, of New Jersey, on some
American species of Drosera. Dr. Burdon Sanderson delivered a lecture
on Dionaea, before the Royal Institution published in 'Nature,' June
14, 1874, in which a short account of my observations on the power of
true digestion possessed by Drosera and Dionaea first appeared. Prof.
Asa Gray has done good service by calling attention to Drosera, and to
other plants having similar habits, in 'The Nation' (1874, pp. 261 and
232), and in other publications. Dr. Hooker, also, in his important
address on Carnivorous Plants (Brit. Assoc., Belfast, 1874), has given
a history of the subject.  [page 2]

gathered by chance a dozen plants, bearing fifty-six fully expanded
leaves, and on thirty-one of these dead insects or remnants of them
adhered; and, no doubt, many more would have been caught afterwards by
these same leaves, and still more by those as yet not expanded. On one
plant all six leaves had caught their prey; and on several plants very
many leaves had caught more than a single insect. On one large leaf I
found the remains of thirteen distinct insects. Flies (Diptera) are
captured much oftener than other insects. The largest kind which I have
seen caught was a small butterfly (Caenonympha pamphilus); but the Rev.
H.M.  Wilkinson informs me that he found a large living dragon-fly with
its body firmly held by two leaves. As this plant is extremely common
in some districts, the number of insects thus annually slaughtered must
be prodigious. Many plants cause the death of insects, for instance the
sticky buds of the horse-chestnut (Aesculus hippocastanum), without
thereby receiving, as far as we can perceive, any advantage; but it was
soon evident that Drosera was [page 3] excellently adapted for the
special purpose of catching insects, so that the subject seemed well
worthy of investigation.

The results have proved highly remarkable; the more important ones
being--firstly, the extraordinary

FIG. 1.* (Drosera rotundifolia.) Leaf viewed from above; enlarged four
times.

sensitiveness of the glands to slight pressure and to minute doses of
certain nitrogenous fluids, as shown by the movements of the so-called
hairs or tentacles;

* The drawings of Drosera and Dionaea, given in this work, were made
for me by my son George Darwin; those of Aldrovanda, and of the several
species of Utricularia, by my son Francis. They have been excellently
reproduced on wood by Mr. Cooper, 188 Strand.  [page 4]

secondly, the power possessed by the leaves of rendering soluble or
digesting nitrogenous substances, and of afterwards absorbing them;
thirdly, the changes which take place within the cells of the
tentacles, when the glands are excited in various ways.

It is necessary, in the first place, to describe briefly the plant. It
bears from two or three to five or six leaves, generally extended more
or less horizontally, but sometimes standing vertically upwards. The
shape and general appearance of a leaf is shown, as seen from above, in
fig. 1, and as seen laterally, in fig. 2. The leaves are commonly a
little broader than long,

FIG. 2.  (Drosera rotundifolia.) Old leaf viewed laterally; enlarged
about five times.

but this was not the case in the one here figured. The whole upper
surface is covered with gland-bearing filaments, or tentacles, as I
shall call them, from their manner of acting. The glands were counted
on thirty-one leaves, but many of these were of unusually large size,
and the average number was 192; the greatest number being 260, and the
least 130. The glands are each surrounded by large drops of extremely
viscid secretion, which, glittering in the sun, have given rise to the
plant's poetical name of the sun-dew.

[The tentacles on the central part of the leaf or disc are short and
stand upright, and their pedicels are green. Towards the margin they
become longer and longer and more inclined [page 5] outwards, with
their pedicels of a purple colour. Those on the extreme margin project
in the same plane with the leaf, or more commonly (see fig. 2) are
considerably reflexed. A few tentacles spring from the base of the
footstalk or petiole, and these are the longest of all, being sometimes
nearly 1/4 of an inch in length. On a leaf bearing altogether 252
tentacles, the short ones on the disc, having green pedicels, were in
number to the longer submarginal and marginal tentacles, having purple
pedicels, as nine to sixteen.

A tentacle consists of a thin, straight, hair-like pedicel, carrying a
gland on the summit. The pedicel is somewhat flattened, and is formed
of several rows of elongated cells, filled with purple fluid or
granular matter.* There is, however, a narrow zone close beneath the
glands of the longer tentacles, and a broader zone near their bases, of
a green tint. Spiral vessels, accompanied by simple vascular tissue,
branch off from the vascular bundles in the blade of the leaf, and run
up all the tentacles into the glands.

Several eminent physiologists have discussed the homological nature of
these appendages or tentacles, that is, whether they ought to be
considered as hairs (trichomes) or prolongations of the leaf. Nitschke
has shown that they include all the elements proper to the blade of a
leaf; and the fact of their including vascular tissue was formerly
thought to prove that they were prolongations of the leaf, but it is
now known that vessels sometimes enter true hairs.  The power of
movement which they possess is a strong argument against their being
viewed as hairs. The conclusion which seems to me the most probable
will be given in Chap. XV., namely that they existed primordially as
glandular hairs, or mere epidermic formations, and that their upper
part should still be so considered; but that their lower

* According to Nitschke ('Bot. Zeitung,' 1861, p. 224) the purple fluid
results from the metamorphosis of chlorophyll. Mr. Sorby examined the
colouring matter with the spectroscope, and informs me that it consists
of the commonest species of erythrophyll, "which is often met with in
leaves with low vitality, and in parts, like the petioles, which carry
on leaf-functions in a very imperfect manner. All that can be said,
therefore, is that the hairs (or tentacles) are coloured like parts of
a leaf which do not fulfil their proper office."

  Dr. Nitschke has discussed this subject in 'Bot. Zeitung,' 1861, p.
  241 &c. See also Dr.  Warming ('Sur la Diffrence entre les Trichomes'
&c., 1873), who gives references to various publications. See also
Groenland and Trcul 'Annal. des Sc. nat. bot.' (4th series), tom. iii.
1855, pp. 297 and 303.  [page 6]

part, which alone is capable of movement, consists of a prolongation of
the leaf; the spiral vessels being extended from this to the uppermost
part. We shall hereafter see that the terminal tentacles of the divided
leaves of Roridula are still in an intermediate condition.

The glands, with the exception of those borne by the extreme

FIG. 3.  (Drosera rotundifolia.) Longitudinal section of a gland;
greatly magnified. From Dr. Warming.

marginal tentacles, are oval, and of nearly uniform size, viz. about
4/500 of an inch in length.  Their structure is remarkable, and their
functions complex, for they secrete, absorb, and are acted on by
various stimulants. They consist of an outer layer of small polygonal
cells, containing purple granular matter or fluid, and with the walls
thicker than those of the pedicels.  [page 7] Within this layer of
cells there is an inner one of differently shaped ones, likewise filled
with purple fluid, but of a slightly different tint, and differently
affected by chloride of gold. These two layers are sometimes well seen
when a gland has been crushed or boiled in caustic potash. According to
Dr. Warming, there is still another layer of much more elongated cells,
as shown in the accompanying section (fig. 3) copied from his work; but
these cells were not seen by Nitschke, nor by me. In the centre there
is a group of elongated, cylindrical cells of unequal lengths, bluntly
pointed at their upper ends, truncated or rounded at their lower ends,
closely pressed together, and remarkable from being surrounded by a
spiral line, which can be separated as a distinct fibre.

These latter cells are filled with limpid fluid, which after long
immersion in alcohol deposits much brown matter. I presume that they
are actually connected with the spiral vessels which run up the
tentacles, for on several occasions the latter were seen to divide into
two or three excessively thin branches, which could be traced close up
to the spiriferous cells. Their development has been described by Dr.
Warming. Cells of the same kind have been observed in other plants, as
I hear from Dr. Hooker, and were seen by me in the margins of the
leaves of Pinguicula. Whatever their function may be, they are not
necessary for the secretion of a digestive fluid, or for absorption, or
for the communication of a motor impulse to other parts of the leaf, as
we may infer from the structure of the glands in some other genera of
the Droseraceae.

The extreme marginal tentacles differ slightly from the others. Their
bases are broader, and besides their own vessels, they receive a fine
branch from those which enter the tentacles on each side. Their glands
are much elongated, and lie embedded on the upper surface of the
pedicel, instead of standing at the apex. In other respects they do not
differ essentially from the oval ones, and in one specimen I found
every possible transition between the two states.  In another specimen
there were no long-headed glands. These marginal tentacles lose their
irritability earlier than the others; and when a stimulus is applied to
the centre of the leaf, they are excited into action after the others.
When cut-off leaves are immersed in water, they alone often become
inflected.

The purple fluid or granular matter which fills the cells of the glands
differs to a certain extent from that within the cells of the pedicels.
For when a leaf is placed in hot water or in certain acids, the glands
become quite white and opaque, whereas [page 8] the cells of the
pedicels are rendered of a bright red, with the exception of those
close beneath the glands. These latter cells lose their pale red tint;
and the green matter which they, as well as the basal cells, contain,
becomes of a brighter green. The petioles bear many multicellular
hairs, some of which near the blade are surmounted, according to
Nitschke, by a few rounded cells, which appear to be rudimentary
glands. Both surfaces of the leaf, the pedicels of the tentacles,
especially the lower sides of the outer ones, and the petioles, are
studded with minute papillae (hairs or trichomes), having a conical
basis, and bearing on their summits two, and occasionally three or even
four, rounded cells, containing much protoplasm. These papillae are
generally colourless, but sometimes include a little purple fluid. They
vary in development, and graduate, as Nitschke* states, and as I
repeatedly observed, into the long multicellular hairs. The latter, as
well as the papillae, are probably rudiments of formerly existing
tentacles.

I may here add, in order not to recur to the papillae, that they do not
secrete, but are easily permeated by various fluids: thus when living
or dead leaves are immersed in a solution of one part of chloride of
gold, or of nitrate of silver, to 437 of water, they are quickly
blackened, and the discoloration soon spreads to the surrounding
tissue. The long multicellular hairs are not so quickly affected. After
a leaf had been left in a weak infusion of raw meat for 10 hours, the
cells of the papillae had evidently absorbed animal matter, for instead
of limpid fluid they now contained small aggregated masses of
protoplasm, which slowly and incessantly changed their forms. A similar
result followed from an immersion of only 15 minutes in a solution of
one part of carbonate of ammonia to 218 of water, and the adjoining
cells of the tentacles, on which the papillae were seated, now likewise
contained aggregated masses of protoplasm. We may therefore conclude
that when a leaf has closely clasped a captured insect in the manner
immediately to be described, the papillae, which project from the upper
surface of the leaf and of the tentacles, probably absorb some of the
animal matter dissolved in the secretion; but this cannot be the case
with the papillae on the backs of the leaves or on the petioles.]

* Nitschke has elaborately described and figured these papillae,  'Bot.
Zeitung,' 1861, pp.  234, 253, 254.  [page 9]

Preliminary Sketch of the Action of the several Parts, and of the
Manner in which Insects are
                           Captured.

If a small organic or inorganic object be placed on the glands in the
centre of a leaf, these transmit a motor impulse to the marginal
tentacles. The nearer ones are first affected and slowly bend towards
the centre, and then those farther off, until at last all become
closely inflected over the object. This takes place in from one hour to
four or five or more hours. The difference in the time required depends
on many circumstances; namely on the size of the object and on its
nature, that is, whether it contains soluble matter of the proper kind;
on the vigour and age of the leaf; whether it has lately been in
action; and, according to Nitschke,* on the temperature of the day, as
likewise seemed to me to be the case. A living insect is a more
efficient object than a dead one, as in struggling it presses against
the glands of many tentacles. An insect, such as a fly, with thin
integuments, through which animal matter in solution can readily pass
into the surrounding dense secretion, is more efficient in causing
prolonged inflection than an insect with a thick coat, such as a
beetle. The inflection of the tentacles takes place indifferently in
the light and darkness; and the plant is not subject to any nocturnal
movement of so-called sleep.

If the glands on the disc are repeatedly touched or brushed, although
no object is left on them, the marginal tentacles curve inwards. So
again, if drops of various fluids, for instance of saliva or of a
solution of any salt of ammonia, are placed on the central glands, the
same result quickly follows, sometimes in under half an hour.

* 'Bot. Zeitung,' 1860, p. 246.  [page 10]

The tentacles in the act of inflection sweep through a wide space; thus
a marginal tentacle, extended in the same plane with the blade, moves
through an angle of 180o; and I have seen the much reflected tentacles
of a leaf which stood upright move through an angle of not less than
270o. The bending part is almost confined to a short space near the
base; but a rather larger portion of the elongated exterior tentacles

FIG. 4.  (Drosera rotundifolia.) Leaf (enlarged) with all the tentacles
closely inflected, from immersion in a solution of phosphate of ammonia
(one part to 87,500 of water.)

FIG. 5.  (Drosera rotundifolia.) Leaf (enlarged) with the tentacles on
one side inflected over a bit of meat placed on the disc.

becomes slightly incurved; the distal half in all cases remaining
straight. The short tentacles in the centre of the disc when directly
excited, do not become inflected; but they are capable of inflection if
excited by a motor impulse received from other glands at a distance.
Thus, if a leaf is immersed in an infusion of raw meat, or in a weak
solution of ammonia (if the [page 11] solution is at all strong, the
leaf is paralysed), all the exterior tentacles bend inwards (see fig.
4), excepting those near the centre, which remain upright; but these
bend towards any exciting object placed on one side of the disc, as
shown in fig. 5. The glands in fig. 4 may be seen to form a dark ring
round the centre; and this follows from the exterior tentacles
increasing in length in due proportion, as they stand nearer to the
circumference.

The kind of inflection which the tentacles undergo is best shown when
the gland of one of the long exterior

FIG. 6.  (Drosera rotundifolia.) Diagram showing one of the exterior
tentacles closely inflected; the two adjoining ones in their ordinary
position.)

tentacles is in any way excited; for the surrounding ones remain
unaffected. In the accompanying outline (fig. 6) we see one tentacle,
on which a particle of meat had been placed, thus bent towards the
centre of the leaf, with two others retaining their original position.
A gland may be excited by being simply touched three or four times, or
by prolonged contact with organic or inorganic objects, and various
fluids. I have distinctly seen, through a lens, a tentacle beginning to
bend in ten seconds, after an object had been [page 12] placed on its
gland; and I have often seen strongly pronounced inflection in under
one minute. It is surprising how minute a particle of any substance,
such as a bit of thread or hair or splinter of glass, if placed in
actual contact with the surface of a gland, suffices to cause the
tentacle to bend. If the object, which has been carried by this
movement to the centre, be not very small, or if it contains soluble
nitrogenous matter, it acts on the central glands; and these transmit a
motor impulse to the exterior tentacles, causing them to bend inwards.

Not only the tentacles, but the blade of the leaf often, but by no
means always, becomes much incurved, when any strongly exciting
substance or fluid is placed on the disc. Drops of milk and of a
solution of nitrate of ammonia or soda are particularly apt to produce
this effect. The blade is thus converted into a little cup. The manner
in which it bends varies greatly. Sometimes the apex alone, sometimes
one side, and sometimes both sides, become incurved. For instance, I
placed bits of hard-boiled egg on three leaves; one had the apex bent
towards the base; the second had both distal margins much incurved, so
that it became almost triangular in outline, and this perhaps is the
commonest case; whilst the third blade was not at all affected, though
the tentacles were as closely inflected as in the two previous cases.
The whole blade also generally rises or bends upwards, and thus forms a
smaller angle with the footstalk than it did before. This appears at
first sight a distinct kind of movement, but it results from the
incurvation of that part of the margin which is attached to the
footstalk, causing the blade, as a whole, to curve or move upwards.

The length of time during which the tentacles as [page 13] well as the
blade remain inflected over an object placed on the disc, depends on
various circumstances; namely on the vigour and age of the leaf, and,
according to Dr. Nitschke, on the temperature, for during cold weather
when the leaves are inactive, they re-expand at an earlier period than
when the weather is warm. But the nature of the object is by far the
most important circumstance; I have repeatedly found that the tentacles
remain clasped for a much longer average time over objects which yield
soluble nitrogenous matter than over those, whether organic or
inorganic, which yield no such matter. After a period varying from one
to seven days, the tentacles and blade re-expand, and are then ready to
act again. I have seen the same leaf inflected three successive times
over insects placed on the disc; and it would probably have acted a
greater number of times.

The secretion from the glands is extremely viscid, so that it can be
drawn out into long threads. It appears colourless, but stains little
balls of paper pale pink. An object of any kind placed on a gland
always causes it, as I believe, to secrete more freely; but the mere
presence of the object renders this difficult to ascertain. In some
cases, however, the effect was strongly marked, as when particles of
sugar were added; but the result in this case is probably due merely to
exosmose. Particles of carbonate and phosphate of ammonia and of some
other salts, for instance sulphate of zinc, likewise increase the
secretion. Immersion in a solution of one part of chloride of gold, or
of some other salts, to 437 of water, excites the glands to largely
increased secretion; on the other hand, tartrate of antimony produces
no such effect.  Immersion in many acids (of the strength of one part
to 437 of water) likewise causes a wonderful amount of [page 14]
secretion, so that when the leaves are lifted out, long ropes of
extremely viscid fluid hang from them. Some acids, on the other hand,
do not act in this manner. Increased secretion is not necessarily
dependent on the inflection of the tentacle, for particles of sugar and
of sulphate of zinc cause no movement.

It is a much more remarkable fact that when an object, such as a bit of
meat or an insect, is placed on the disc of a leaf, as soon as the
surrounding tentacles become considerably inflected, their glands pour
forth an increased amount of secretion. I ascertained this by selecting
leaves with equal-sized drops on the two sides, and by placing bits of
meat on one side of the disc; and as soon as the tentacles on this side
became much inflected, but before the glands touched the meat, the
drops of secretion became larger. This was repeatedly observed, but a
record was kept of only thirteen cases, in nine of which increased
secretion was plainly observed; the four failures being due either to
the leaves being rather torpid, or to the bits of meat being too small
to cause much inflection. We must therefore conclude that the central
glands, when strongly excited, transmit some influence to the glands of
the circumferential tentacles, causing them to secrete more copiously.

It is a still more important fact (as we shall see more fully when we
treat of the digestive power of the secretion) that when the tentacles
become inflected, owing to the central glands having been stimulated
mechanically, or by contact with animal matter, the secretion not only
increases in quantity, but changes its nature and becomes acid; and
this occurs before the glands have touched the object on the centre of
the leaf. This acid is of a different nature from that contained in the
tissue of the leaves. As long as the [page 15] tentacles remain closely
inflected, the glands continue to secrete, and the secretion is acid;
so that, if neutralised by carbonate of soda, it again becomes acid
after a few hours. I have observed the same leaf with the tentacles
closely inflected over rather indigestible substances, such as
chemically prepared casein, pouring forth acid secretion for eight
successive days, and over bits of bone for ten successive days.

The secretion seems to possess, like the gastric juice of the higher
animals, some antiseptic power. During very warm weather I placed close
together two equal-sized bits of raw meat, one on a leaf of the
Drosera, and the other surrounded by wet moss. They were thus left for
48 hrs., and then examined. The bit on the moss swarmed with infusoria,
and was so much decayed that the transverse striae on the muscular
fibres could no longer be clearly distinguished; whilst the bit on the
leaf, which was bathed by the secretion, was free from infusoria, and
its striae were perfectly distinct in the central and undissolved
portion. In like manner small cubes of albumen and cheese placed on wet
moss became threaded with filaments of mould, and had their surfaces
slightly discoloured and disintegrated; whilst those on the leaves of
Drosera remained clean, the albumen being changed into transparent
fluid.

As soon as tentacles, which have remained closely inflected during
several days over an object, begin to re-expand, their glands secrete
less freely, or cease to secrete, and are left dry. In this state they
are covered with a film of whitish, semi-fibrous matter, which was held
in solution by the secretion. The drying of the glands during the act
of re-expansion is of some little service to the plant; for I have
often observed that objects adhering to the leaves [page 16] could then
be blown away by a breath of air; the leaves being thus left
unencumbered and free for future action. Nevertheless, it often happens
that all the glands do not become completely dry; and in this case
delicate objects, such as fragile insects, are sometimes torn by the
re-expansion of the tentacles into fragments, which remain scattered
all over the leaf.  After the re-expansion is complete, the glands
quickly begin to re-secrete, and as soon as full-sized drops are
formed, the tentacles are ready to clasp a new object.

When an insect alights on the central disc, it is instantly entangled
by the viscid secretion, and the surrounding tentacles after a time
begin to bend, and ultimately clasp it on all sides.  Insects are
generally killed, according to Dr. Nitschke, in about a quarter of an
hour, owing to their tracheae being closed by the secretion. If an
insect adheres to only a few of the glands of the exterior tentacles,
these soon become inflected and carry their prey to the tentacles next
succeeding them inwards; these then bend inwards, and so onwards; until
the insect is ultimately carried by a curious sort of rolling movement
to the centre of the leaf. Then, after an interval, the tentacles on
all sides become inflected and bathe their prey with their secretion,
in the same manner as if the insect had first alighted on the central
disc. It is surprising how minute an insect suffices to cause this
action: for instance, I have seen one of the smallest species of gnats
(Culex), which had just settled with its excessively delicate feet on
the glands of the outermost tentacles, and these were already beginning
to curve inwards, though not a single gland had as yet touched the body
of the insect. Had I not interfered, this minute gnat would [page 17]
assuredly have been carried to the centre of the leaf and been securely
clasped on all sides.  We shall hereafter see what excessively small
doses of certain organic fluids and saline solutions cause strongly
marked inflection.

Whether insects alight on the leaves by mere chance, as a resting
place, or are attracted by the odour of the secretion, I know not. I
suspect from the number of insects caught by the English species of
Drosera, and from what I have observed with some exotic species kept in
my greenhouse, that the odour is attractive. In this latter case the
leaves may be compared with a baited trap; in the former case with a
trap laid in a run frequented by game, but without any bait.

That the glands possess the power of absorption, is shown by their
almost instantaneously becoming dark-coloured when given a minute
quantity of carbonate of ammonia; the change of colour being chiefly or
exclusively due to the rapid aggregation of their contents. When
certain other fluids are added, they become pale-coloured. Their power
of absorption is, however, best shown by the widely different results
which follow, from placing drops of various nitrogenous and
non-nitrogenous fluids of the same density on the glands of the disc,
or on a single marginal gland; and likewise by the very different
lengths of time during which the tentacles remain inflected over
objects, which yield or do not yield soluble nitrogenous matter. This
same conclusion might indeed have been inferred from the structure and
movements of the leaves, which are so admirably adapted for capturing
insects.

The absorption of animal matter from captured insects explains how
Drosera can flourish in extremely poor peaty soil,--in some cases where
nothing but [page 18] sphagnum moss grows, and mosses depend altogether
on the atmosphere for their nourishment. Although the leaves at a hasty
glance do not appear green, owing to the purple colour of the
tentacles, yet the upper and lower surfaces of the blade, the pedicels
of the central tentacles, and the petioles contain chlorophyll, so
that, no doubt, the plant obtains and assimilates carbonic acid from
the air. Nevertheless, considering the nature of the soil where it
grows, the supply of nitrogen would be extremely limited, or quite
deficient, unless the plant had the power of obtaining this important
element from captured insects. We can thus understand how it is that
the roots are so poorly developed. These usually consist of only two or
three slightly divided branches, from half to one inch in length,
furnished with absorbent hairs. It appears, therefore, that the roots
serve only to imbibe water; though, no doubt, they would absorb
nutritious matter if present in the soil; for as we shall hereafter
see, they absorb a weak solution of carbonate of ammonia. A plant of
Drosera, with the edges of its leaves curled inwards, so as to form a
temporary stomach, with the glands of the closely inflected tentacles
pouring forth their acid secretion, which dissolves animal matter,
afterwards to be absorbed, may be said to feed like an animal. But,
differently from an animal, it drinks by means of its roots; and it
must drink largely, so as to retain many drops of viscid fluid round
the glands, sometimes as many as 260, exposed during the whole day to a
glaring sun.  [page 19]



                          CHAPTER II.

THE MOVEMENTS OF THE TENTACLES FROM THE CONTACT OF SOLID BODIES.

Inflection of the exterior tentacles owing to the glands of the disc
being excited by repeated touches, or by objects left in contact with
them--Difference in the action of bodies yielding and not yielding
soluble nitrogenous matter--Inflection of the exterior tentacles
directly caused by objects left in contact with their glands--Periods
of commencing inflection and of subsequent re-expansion--Extreme
minuteness of the particles causing inflection--Action under
water--Inflection of the exterior tentacles when their glands are
excited by repeated touches--Falling drops of water do not cause
inflection.

I WILL give in this and the following chapters some of the many
experiments made, which best illustrate the manner and rate of movement
of the tentacles, when excited in various ways. The glands alone in all
ordinary cases are susceptible to excitement. When excited, they do not
themselves move or change form, but transmit a motor impulse to the
bending part of their own and adjoining tentacles, and are thus carried
towards the centre of the leaf.  Strictly speaking, the glands ought to
be called irritable, as the term sensitive generally implies
consciousness; but no one supposes that the Sensitive-plant is
conscious, and as I have found the term convenient, I shall use it
without scruple. I will commence with the movements of the exterior
tentacles, when indirectly excited by stimulants applied to the glands
of the short tentacles on the disc. The exterior tentacles may be said
in this case to be indirectly excited, because their own glands are not
directly acted on. The stimulus proceeding from the glands of the disc
acts on the bending part of the [page 20] exterior tentacles, near
their bases, and does not (as will hereafter be proved) first travel up
the pedicels to the glands, to be then reflected back to the bending
place. Nevertheless, some influence does travel up to the glands,
causing them to secrete more copiously, and the secretion to become
acid. This latter fact is, I believe, quite new in the physiology of
plants; it has indeed only recently been established that in the animal
kingdom an influence can be transmitted along the nerves to glands,
modifying their power of secretion, independently of the state of the
blood-vessels.

The Inflection of the Exterior Tentacles from the Glands of the Disc
being excited by Repeated Touches, or by Objects left in Contact with
them.

The central glands of a leaf were irritated with a small stiff
camel-hair brush, and in 70 m.  (minutes) several of the outer
tentacles were inflected; in 5 hrs. (hours) all the sub-marginal
tentacles were inflected; next morning after an interval of about 22
hrs. they were fully re-expanded. In all the following cases the period
is reckoned from the time of first irritation.  Another leaf treated in
the same manner had a few tentacles inflected in 20 m.; in 4 hrs. all
the submarginal and some of the extreme marginal tentacles, as well as
the edge of the leaf itself, were inflected; in 17 hrs. they had
recovered their proper, expanded position. I then put a dead fly in the
centre of the last-mentioned leaf, and next morning it was closely
clasped; five days afterwards the leaf re-expanded, and the tentacles,
with their glands surrounded by secretion, were ready to act again.

Particles of meat, dead flies, bits of paper, wood, dried moss, sponge,
cinders, glass, &c., were repeatedly [page 21] placed on leaves, and
these objects were well embraced in various periods from one hr. to as
long as 24 hrs., and set free again, with the leaf fully re-expanded,
in from one or two, to seven or even ten days, according to the nature
of the object. On a leaf which had naturally caught two flies, and
therefore had already closed and reopened either once or more probably
twice, I put a fresh fly: in 7 hrs. it was moderately, and in 21 hrs.
thoroughly well, clasped, with the edges of the leaf inflected. In two
days and a half the leaf had nearly re-expanded; as the exciting object
was an insect, this unusually short period of inflection was, no doubt,
due to the leaf having recently been in action. Allowing this same leaf
to rest for only a single day, I put on another fly, and it again
closed, but now very slowly; nevertheless, in less than two days it
succeeded in thoroughly clasping the fly.

When a small object is placed on the glands of the disc, on one side of
a leaf, as near as possible to its circumference, the tentacles on this
side are first affected, those on the opposite side much later, or, as
often occurred, not at all. This was repeatedly proved by trials with
bits of meat; but I will here give only the case of a minute fly,
naturally caught and still alive, which I found adhering by its
delicate feet to the glands on the extreme left side of the central
disc. The marginal tentacles on this side closed inwards and killed the
fly, and after a time the edge of the leaf on this side also became
inflected, and thus remained for several days, whilst neither the
tentacles nor the edge on the opposite side were in the least
affected.

If young and active leaves are selected, inorganic particles not larger
than the head of a small pin, placed on the central glands, sometimes
cause the [page 22] outer tentacles to bend inwards. But this follows
much more surely and quickly, if the object contains nitrogenous matter
which can be dissolved by the secretion. On one occasion I observed the
following unusual circumstance. Small bits of raw meat (which acts more
energetically than any other substance), of paper, dried moss, and of
the quill of a pen were placed on several leaves, and they were all
embraced equally well in about 2 hrs. On other occasions the
above-named substances, or more commonly particles of glass,
coal-cinder (taken from the fire), stone, gold-leaf, dried grass, cork,
blotting-paper, cotton-wool, and hair rolled up into little balls, were
used, and these substances, though they were sometimes well embraced,
often caused no movement whatever in the outer tentacles, or an
extremely slight and slow movement. Yet these same leaves were proved
to be in an active condition, as they were excited to move by
substances yielding soluble nitrogenous matter, such as bits of raw or
roast meat, the yolk or white of boiled eggs, fragments of insects of
all orders, spiders, &c.  I will give only two instances. Minute flies
were placed on the discs of several leaves, and on others balls of
paper, bits of moss and quill of about the same size as the flies, and
the latter were well embraced in a few hours; whereas after 25 hrs.
only a very few tentacles were inflected over the other objects. The
bits of paper, moss, and quill were then removed from these leaves, and
bits of raw meat placed on them; and now all the tentacles were soon
energetically inflected.

Again, particles of coal-cinder (weighing rather more than the flies
used in the last experiment) were placed on the centres of three
leaves: after an interval of 19 hrs. one of the particles was tolerably
well embraced; [page 23] a second by a very few tentacles; and a third
by none. I then removed the particles from the two latter leaves, and
put on them recently killed flies. These were fairly well embraced in 7
1/2 hrs. and thoroughly after 20 1/2 hrs.; the tentacles remaining
inflected for many subsequent days. On the other hand, the one leaf
which had in the course of 19 hrs. embraced the bit of cinder
moderately well, and to which no fly was given, after an additional 33
hrs.  (i.e. in 52 hrs. from the time when the cinder was put on) was
completely re-expanded and ready to act again.

From these and numerous other experiments not worth giving, it is
certain that inorganic substances, or such organic substances as are
not attacked by the secretion, act much less quickly and efficiently
than organic substances yielding soluble matter which is absorbed.
Moreover, I have met with very few exceptions to the rule, and these
exceptions apparently depended on the leaf having been too recently in
action, that the tentacles remain clasped for a much longer time over
organic bodies of the nature just specified than over those which are
not acted on by the secretion, or over inorganic objects.*

* Owing to the extraordinary belief held by M. Ziegler ('Comptes
rendus,' May 1872, p. 122), that albuminous substances, if held for a
moment between the fingers, acquire the property of making the
tentacles of Drosera contract, whereas, if not thus held, they have no
such power, I tried some experiments with great care, but the results
did not confirm this belief. Red-hot cinders were taken out of the
fire, and bits of glass, cotton-thread, blotting paper and thin slices
of cork were immersed in boiling water; and particles were then placed
(every instrument with which they were touched having been previously
immersed in boiling water) on the glands of several leaves, and they
acted in exactly the same manner as other particles, which had been
purposely handled for some time. Bits of a boiled egg, cut with a knife
which had been washed in boiling water, also acted like any other
animal substance. I breathed on some leaves for above a minute, and
repeated the act two or three times, with my mouth close to [[page 24]]
them, but this produced no effect. I may here add, as showing that the
leaves are not acted on by the odour of nitrogenous substances, that
pieces of raw meat stuck on needles were fixed as close as possible,
without actual contact, to several leaves, but produced no effect
whatever. On the other hand, as we shall hereafter see, the vapours of
certain volatile substances and fluids, such as of carbonate of
ammonia, chloroform, certain essential oils, &c., cause inflection. M.
Ziegler makes still more extraordinary statements with respect to the
power of animal substances, which have been left close to, but not in
contact with, sulphate of quinine. The action of salts of quinine will
be described in a future chapter. Since the appearance of the paper
above referred to, M. Ziegler has published a book on the same subject,
entitled 'Atonicit et Zoicit,' 1874.) [page 24]

The Inflection of the Exterior Tentacles as directly caused by Objects
left in Contact with their Glands.

I made a vast number of trials by placing, by means of a fine needle
moistened with distilled water, and with the aid of a lens, particles
of various substances on the viscid secretion surrounding the glands of
the outer tentacles. I experimented on both the oval and long-headed
glands. When a particle is thus placed on a single gland, the movement
of the tentacle is particularly well seen in contrast with the
stationary condition of the surrounding tentacles. (See previous fig.
6.) In four cases small particles of raw meat caused the tentacles to
be greatly inflected in between 5 and 6 m. Another tentacle similarly
treated, and observed with special care, distinctly, though slightly,
changed its position in 10 s. (seconds); and this is the quickest
movement seen by me. In 2 m. 30 s. it had moved through an angle of
about 45o. The movement as seen through a lens resembled that of the
hand of a large clock. In 5 m. it had moved through 90o, and when I
looked again after 10 m., the particle had reached the centre of the
leaf; so that the whole movement was completed in less [page 25] than
17 m. 30 s. In the course of some hours this minute bit of meat, from
having been brought into contact with some of the glands of the central
disc, acted centrifugally on the outer tentacles, which all became
closely inflected. Fragments of flies were placed on the glands of four
of the outer tentacles, extended in the same plane with that of the
blade, and three of these fragments were carried in 35 m. through an
angle of 180o to the centre. The fragment on the fourth tentacle was
very minute, and it was not carried to the centre until 3 hrs. had
elapsed. In three other cases minute flies or portions of larger ones
were carried to the centre in 1 hr. 30 s. In these seven cases, the
fragments or small flies, which had been carried by a single tentacle
to the central glands, were well embraced by the other tentacles after
an interval of from 4 to 10 hrs.

I also placed in the manner just described six small balls of
writing-paper (rolled up by the aid of pincers, so that they were not
touched by my fingers) on the glands of six exterior tentacles on
distinct leaves; three of these were carried to the centre in about 1
hr., and the other three in rather more than 4 hrs.; but after 24 hrs.
only two of the six balls were well embraced by the other tentacles. It
is possible that the secretion may have dissolved a trace of glue or
animalised matter from the balls of paper. Four particles of
coal-cinder were then placed on the glands of four exterior tentacles;
one of these reached the centre in 3 hrs. 40 m.; the second in 9 hrs.;
the third within 24 hrs., but had moved only part of the way in 9 hrs.;
whilst the fourth moved only a very short distance in 24 hrs., and
never moved any farther.  Of the above three bits of cinder which were
ultimately carried to the centre, one alone was well embraced by [page
26] many of the other tentacles. We here see clearly that such bodies
as particles of cinder or little balls of paper, after being carried by
the tentacles to the central glands, act very differently from
fragments of flies, in causing the movement of the surrounding
tentacles.

I made, without carefully recording the times of movement, many similar
trials with other substances, such as splinters of white and blue
glass, particles of cork, minute bits of gold-leaf, &c.; and the
proportional number of cases varied much in which the tentacles reached
the centre, or moved only slightly, or not at all. One evening,
particles of glass and cork, rather larger than those usually employed,
were placed on about a dozen glands, and next morning, after 13 hrs.,
every single tentacle had carried its little load to the centre; but
the unusually large size of the particles will account for this result.
In another case 6/7 of the particles of cinder, glass, and thread,
placed on separate glands, were carried towards, or actually to, the
centre; in another case 7/9, in another 7/12, and in the last case only
7/26 were thus carried inwards, the small proportion being here due, at
least in part, to the leaves being rather old and inactive.
Occasionally a gland, with its light load, could be seen through a
strong lens to move an extremely short distance and then stop; this was
especially apt to occur when excessively minute particles, much less
than those of which the measurements will be immediately given, were
placed on glands; so that we here have nearly the limit of any action.

I was so much surprised at the smallness of the particles which caused
the tentacles to become greatly inflected that it seemed worth while
carefully to ascertain how minute a particle would plainly act.  [page
27] Accordingly measured lengths of a narrow strip of blotting paper,
of fine cotton-thread, and of a woman's hair, were carefully weighed
for me by Mr. Trenham Reeks, in an excellent balance, in the laboratory
in Jermyn Street. Short bits of the paper, thread, and hair were then
cut off and measured by a micrometer, so that their weights could be
easily calculated. The bits were placed on the viscid secretion
surrounding the glands of the exterior tentacles, with the precautions
already stated, and I am certain that the gland itself was never
touched; nor indeed would a single touch have produced any effect. A
bit of the blotting-paper, weighing 1/465 of a grain, was placed so as
to rest on three glands together, and all three tentacles slowly curved
inwards; each gland, therefore, supposing the weight to be distributed
equally, could have been pressed on by only 1/1395 of a grain, or .0464
of a milligramme. Five nearly equal bits of cotton-thread were tried,
and all acted. The shortest of these was 1/50 of an inch in length, and
weighed 1/8197 of a grain. The tentacle in this case was considerably
inflected in 1 hr. 30 m., and the bit of thread was carried to the
centre of the leaf in 1 hr. 40 m. Again, two particles of the thinner
end of a woman's hair, one of these being 18/1000 of an inch in length,
and weighing 1/35714 of a grain, the other 19/1000 of an inch in
length, and weighing of course a little more, were placed on two glands
on opposite sides of the same leaf, and these two tentacles were
inflected halfway towards the centre in 1 hr. 10 m.; all the many other
tentacles round the same leaf remaining motionless. The appearance of
this one leaf showed in an unequivocal manner that these minute
particles sufficed to cause the tentacles to bend. Altogether, ten such
particles of hair were placed on ten glands on several leaves, and
seven of them caused [page 28] the tentacles to move in a conspicuous
manner. The smallest particle which was tried, and which acted plainly,
was only 8/1000 of an inch (.203 millimetre) in length, and weighed the
1/78740 of a grain, or .000822 milligramme. In these several cases, not
only was the inflection of the tentacles conspicuous, but the purple
fluid within their cells became aggregated into little masses of
protoplasm, in the manner to be described in the next chapter; and the
aggregation was so plain that I could, by this clue alone, have readily
picked out under the microscope all the tentacles which had carried
their light loads towards the centre, from the hundreds of other
tentacles on the same leaves which had not thus acted.

My surprise was greatly excited, not only by the minuteness of the
particles which caused movement, but how they could possibly act on the
glands; for it must be remembered that they were laid with the greatest
care on the convex surface of the secretion. At first I thought--but,
as I now know, erroneously--that particles of such low specific gravity
as those of cork, thread, and paper, would never come into contact with
the surfaces of the glands.  The particles cannot act simply by their
weight being added to that of the secretion, for small drops of water,
many times heavier than the particles, were repeatedly added, and never
produced any effect. Nor does the disturbance of the secretion produce
any effect, for long threads were drawn out by a needle, and affixed to
some adjoining object, and thus left for hours; but the tentacles
remained motionless.

I also carefully removed the secretion from four glands with a sharply
pointed piece of blotting-paper, so that they were exposed for a time
naked to the air, but this caused no movement; yet these glands were
[page 29] in an efficient state, for after 24 hrs. had elapsed, they
were tried with bits of meat, and all became quickly inflected. It then
occurred to me that particles floating on the secretion would cast
shadows on the glands, which might be sensitive to the interception of
the light.  Although this seemed highly improbable, as minute and thin
splinters of colourless glass acted powerfully, nevertheless, after it
was dark, I put on, by the aid of a single tallow candle, as quickly as
possible, particles of cork and glass on the glands of a dozen
tentacles, as well as some of meat on other glands, and covered them up
so that not a ray of light could enter; but by the next morning, after
an interval of 13 hrs., all the particles were carried to the centres
of the leaves.

These negative results led me to try many more experiments, by placing
particles on the surface of the drops of secretion, observing, as
carefully as I could, whether they penetrated it and touched the
surface of the glands. The secretion, from its weight, generally forms
a thicker layer on the under than on the upper sides of the glands,
whatever may be the position of the tentacles. Minute bits of dry cork,
thread, blotting paper, and coal cinders were tried, such as those
previously employed; and I now observed that they absorbed much more of
the secretion, in the course of a few minutes, than I should have
thought possible; and as they had been laid on the upper surface of the
secretion, where it is thinnest, they were often drawn down, after a
time, into contact with at least some one point of the gland. With
respect to the minute splinters of glass and particles of hair, I
observed that the secretion slowly spread itself a little over their
surfaces, by which means they were likewise drawn downwards or
sideways, and thus one end, or some minute [page 30] prominence, often
came to touch, sooner or later, the gland.

In the foregoing and following cases, it is probable that the
vibrations, to which the furniture in every room is continually liable,
aids in bringing the particles into contact with the glands.  But as it
was sometimes difficult, owing to the refraction of the secretion, to
feel sure whether the particles were in contact, I tried the following
experiment. Unusually minute particles of glass, hair, and cork, were
gently placed on the drops round several glands, and very few of the
tentacles moved. Those which were not affected were left for about half
an hour, and the particles were then disturbed or tilted up several
times with a fine needle under the microscope, the glands not being
touched. And now in the course of a few minutes almost all the hitherto
motionless tentacles began to move; and this, no doubt, was caused by
one end or some prominence of the particles having come into contact
with the surface of the glands. But as the particles were unusually
minute, the movement was small.

Lastly, some dark blue glass pounded into fine splinters was used, in
order that the points of the particles might be better distinguished
when immersed in the secretion; and thirteen such particles were placed
in contact with the depending and therefore thicker part of the drops
round so many glands. Five of the tentacles began moving after an
interval of a few minutes, and in these cases I clearly saw that the
particles touched the lower surface of the gland. A sixth tentacle
moved after 1 hr. 45 m., and the particle was now in contact with the
gland, which was not the case at first. So it was with the seventh
tentacle, but its movement did not begin until 3 hrs. 45 m. had [page
31] elapsed. The remaining six tentacles never moved as long as they
were observed; and the particles apparently never came into contact
with the surfaces of the glands.

From these experiments we learn that particles not containing soluble
matter, when placed on glands, often cause the tentacles to begin
bending in the course of from one to five minutes; and that in such
cases the particles have been from the first in contact with the
surfaces of the glands. When the tentacles do not begin moving for a
much longer time, namely, from half an hour to three or four hours, the
particles have been slowly brought into contact with the glands, either
by the secretion being absorbed by the particles or by its gradual
spreading over them, together with its consequent quicker evaporation.
When the tentacles do not move at all, the particles have never come
into contact with the glands, or in some cases the tentacles may not
have been in an active condition. In order to excite movement, it is
indispensable that the particles should actually rest on the glands;
for a touch once, twice, or even thrice repeated by any hard body is
not sufficient to excite movement.

Another experiment, showing that extremely minute particles act on the
glands when immersed in water, may here be given. A grain of sulphate
of quinine was added to an ounce of water, which was not afterwards
filtered; and on placing three leaves in ninety minims of this fluid, I
was much surprised to find that all three leaves were greatly inflected
in 15 m.; for I knew from previous trials that the solution does not
act so quickly as this. It immediately occurred to me that the
particles of the undissolved salt, which were so light as to float
about, might have come [page 32] into contact with the glands, and
caused this rapid movement. Accordingly I added to some distilled water
a pinch of a quite innocent substance, namely, precipitated carbonate
of lime, which consists of an impalpable powder; I shook the mixture,
and thus got a fluid like thin milk. Two leaves were immersed in it,
and in 6 m. almost every tentacle was much inflected.  I placed one of
these leaves under the microscope, and saw innumerable atoms of lime
adhering to the external surface of the secretion. Some, however, had
penetrated it, and were lying on the surfaces of the glands; and no
doubt it was these particles which caused the tentacles to bend. When a
leaf is immersed in water, the secretion instantly swells much; and I
presume that it is ruptured here and there, so that little eddies of
water rush in. If so, we can understand how the atoms of chalk, which
rested on the surfaces of the glands, had penetrated the secretion.
Anyone who has rubbed precipitated chalk between his fingers will have
perceived how excessively fine the powder is. No doubt there must be a
limit, beyond which a particle would be too small to act on a gland;
but what this limit is, I know not. I have often seen fibres and dust,
which had fallen from the air, on the glands of plants kept in my room,
and these never induced any movement; but then such particles lay on
the surface of the secretion and never reached the gland itself.

Finally, it is an extraordinary fact that a little bit of soft thread,
1/50 of an inch in length and weighing 1/8197 of a grain, or of a human
hair, 8/1000 of an inch in length and weighing only 1/78740 of a grain
(.000822 milligramme), or particles of precipitated chalk, after
resting for a short time on a gland, should induce some change in its
cells, exciting them [page 33] to transmit a motor impulse throughout
the whole length of the pedicel, consisting of about twenty cells, to
near its base, causing this part to bend, and the tentacle to sweep
through an angle of above 180o. That the contents of the cells of the
glands, and afterwards those of the pedicels, are affected in a plainly
visible manner by the pressure of minute particles, we shall have
abundant evidence when we treat of the aggregation of protoplasm. But
the case is much more remarkable than as yet stated; for the particles
are supported by the viscid and dense secretion; nevertheless, even
smaller ones than those of which the measurements have been given, when
brought by an insensibly slow movement, through the means above
specified, into contact with the surface of a gland, act on it, and the
tentacle bends. The pressure exerted by the particle of hair, weighing
only 1/78740 of a grain and supported by a dense fluid, must have been
inconceivably slight. We may conjecture that it could hardly have
equalled the millionth of a grain; and we shall hereafter see that far
less than the millionth of a grain of phosphate of ammonia in solution,
when absorbed by a gland, acts on it and induces movement. A bit of
hair, 1/50 of an inch in length, and therefore much larger than those
used in the above experiments, was not perceived when placed on my
tongue; and it is extremely doubtful whether any nerve in the human
body, even if in an inflamed condition, would be in any way affected by
such a particle supported in a dense fluid, and slowly brought into
contact with the nerve. Yet the cells of the glands of Drosera are thus
excited to transmit a motor impulse to a distant point, inducing
movement. It appears to me that hardly any more remarkable fact than
this has been observed in the vegetable kingdom.  [page 34]

The Inflection of the Exterior Tentacles, when their Glands are excited
by Repeated Touches.

We have already seen that, if the central glands are excited by being
gently brushed, they transmit a motor impulse to the exterior
tentacles, causing them to bend; and we have now to consider the
effects which follow from the glands of the exterior tentacles being
themselves touched. On several occasions, a large number of glands were
touched only once with a needle or fine brush, hard enough to bend the
whole flexible tentacle; and though this must have caused a
thousand-fold greater pressure than the weight of the above described
particles, not a tentacle moved. On another occasion forty-five glands
on eleven leaves were touched once, twice, or even thrice, with a
needle or stiff bristle. This was done as quickly as possible, but with
force sufficient to bend the tentacles; yet only six of them became
inflected,--three plainly, and three in a slight degree. In order to
ascertain whether these tentacles which were not affected were in an
efficient state, bits of meat were placed on ten of them, and they all
soon became greatly incurved. On the other hand, when a large number of
glands were struck four, five, or six times with the same force as
before, a needle or sharp splinter of glass being used, a much larger
proportion of tentacles became inflected; but the result was so
uncertain as to seem capricious. For instance, I struck in the above
manner three glands, which happened to be extremely sensitive, and all
three were inflected almost as quickly, as if bits of meat had been
placed on them. On another occasion I gave a single for- [page 35]
cible touch to a considerable number of glands, and not one moved; but
these same glands, after an interval of some hours, being touched four
or five times with a needle, several of the tentacles soon became
inflected.

The fact of a single touch or even of two or three touches not causing
inflection must be of some service to the plant; as during stormy
weather, the glands cannot fail to be occasionally touched by the tall
blades of grass, or by other plants growing near; and it would be a
great evil if the tentacles were thus brought into action, for the act
of re-expansion takes a considerable time, and until the tentacles are
re-expanded they cannot catch prey. On the other hand, extreme
sensitiveness to slight pressure is of the highest service to the
plant; for, as we have seen, if the delicate feet of a minute
struggling insect press ever so lightly on the surfaces of two or three
glands, the tentacles bearing these glands soon curl inwards and carry
the insect with them to the centre, causing, after a time, all the
circumferential tentacles to embrace it. Nevertheless, the movements of
the plant are not perfectly adapted to its requirements; for if a bit
of dry moss, peat, or other rubbish, is blown on to the disc, as often
happens, the tentacles clasp it in a useless manner. They soon,
however, discover their mistake and release such innutritious objects.

It is also a remarkable fact, that drops of water falling from a
height, whether under the form of natural or artificial rain, do not
cause the tentacles to move; yet the drops must strike the glands with
considerable force, more especially after the secretion has been all
washed away by heavy rain; and this often occurs, [page 36] though the
secretion is so viscid that it can be removed with difficulty merely by
waving the leaves in water. If the falling drops of water are small,
they adhere to the secretion, the weight of which must be increased in
a much greater degree, as before remarked, than by the addition of
minute particles of solid matter; yet the drops never cause the
tentacles to become inflected. It would obviously have been a great
evil to the plant (as in the case of occasional touches) if the
tentacles were excited to bend by every shower of rain; but this evil
has been avoided by the glands either having become through habit
insensible to the blows and prolonged pressure of drops of water, or to
their having been originally rendered sensitive solely to the contact
of solid bodies. We shall hereafter see that the filaments on the
leaves of Dionaea are likewise insensible to the impact of fluids,
though exquisitely sensitive to momentary touches from any solid body.

When the pedicel of a tentacle is cut off by a sharp pair of scissors
quite close beneath the gland, the tentacle generally becomes
inflected. I tried this experiment repeatedly, as I was much surprised
at the fact, for all other parts of the pedicels are insensible to any
stimulus.  These headless tentacles after a time re-expand; but I shall
return to this subject. On the other hand, I occasionally succeeded in
crushing a gland between a pair of pincers, but this caused no
inflection. In this latter case the tentacles seem paralysed, as
likewise follows from the action of too strong solutions of certain
salts, and by too great heat, whilst weaker solutions of the same salts
and a more gentle heat cause movement. We shall also see in future
chapters that various other fluids, some [page 37] vapours, and oxygen
(after the plant has been for some time excluded from its action), all
induce inflection, and this likewise results from an induced galvanic
current.*

* My son Francis, guided by the observations of Dr. Burdon Sanderson on
Dionaea, finds that if two needles are inserted into the blade of a
leaf of Drosera, the tentacles do not move; but that if similar needles
in connection with the secondary coil of a Du Bois inductive apparatus
are inserted, the tentacles curve inwards in the course of a few
minutes. My son hopes soon to publish an account of his observations.
[page 38]



                          CHAPTER III.

AGGREGATION OF THE PROTOPLASM WITHIN THE CELLS OF THE TENTACLES.

Nature of the contents of the cells before aggregation--Various causes
which excite aggregation--The process commences within the glands and
travels down the tentacles-- Description of the aggregated masses and
of their spontaneous movements--Currents of protoplasm along the walls
of the cells--Action of carbonate of ammonia--The granules in the
protoplasm which flows along the walls coalesce with the central
masses--Minuteness of the quantity of carbonate of ammonia causing
aggregation--Action of other salts of ammonia--Of other substances,
organic fluids, &c.--Of water--Of heat--Redissolution of the aggregated
masses--Proximate causes of the aggregation of the protoplasm--Summary
and concluding remarks--Supplementary observations on aggregation in
the roots of plants.

I WILL here interrupt my account of the movements of the leaves, and
describe the phenomenon of aggregation, to which subject I have already
alluded. If the tentacles of a young, yet fully matured leaf, that has
never been excited or become inflected, be examined, the cells forming
the pedicels are seen to be filled with homogeneous, purple fluid. The
walls are lined by a layer of colourless, circulating protoplasm; but
this can be seen with much greater distinctness after the process of
aggregation has been partly effected than before. The purple fluid
which exudes from a crushed tentacle is somewhat coherent, and does not
mingle with the surrounding water; it contains much flocculent or
granular matter. But this matter may have been generated by the cells
having been crushed; some degree of aggregation having been thus almost
instantly caused.  [page 39]

If a tentacle is examined some hours after the gland has been excited
by repeated touches, or by an inorganic or organic particle placed on
it, or by the absorption of certain fluids, it presents a wholly
changed appearance. The cells, instead of being filled with homogeneous
purple fluid, now contain variously shaped masses of purple matter,
suspended in a colourless or almost colourless fluid. The change is so
conspicuous that it is visible through a weak lens, and even sometimes
by the naked eye; the tentacles now have a mottled appearance, so that
one thus affected can be picked out with ease from all the others. The
same result follows if the glands on the disc are irritated in any
manner, so that the exterior tentacles become inflected; for their
contents will then be found in an aggregated condition, although their
glands have not as yet touched any object. But aggregation may occur
independently of inflection, as we shall presently see. By whatever
cause the process may have been excited, it commences within the
glands, and then travels down the tentacles. It can be observed much
more distinctly in the upper cells of the pedicels than within the
glands, as these are somewhat opaque. Shortly after the tentacles have
re-expanded, the little masses of protoplasm are all redissolved, and
the purple fluid within the cells becomes as homogeneous and
transparent as it was at first. The process of redissolution travels
upwards from the bases of the tentacles to the glands, and therefore in
a reversed direction to that of aggregation. Tentacles in an aggregated
condition were shown to Prof. Huxley, Dr. Hooker, and Dr. Burdon
Sanderson, who observed the changes under the microscope, and were much
struck with the whole phenomenon.  [page 40]

The little masses of aggregated matter are of the most diversified
shapes, often spherical or oval, sometimes much elongated, or quite
irregular with thread- or necklace-like or club-formed projections.
They consist of thick, apparently viscid matter, which in the exterior
tentacles is of a purplish, and in the short distal tentacles of a
greenish, colour. These little masses incessantly change their forms
and positions, being never at rest. A single mass will often separate
into two, which afterwards reunite. Their movements are rather slow,
and resemble those of Amoebae or of the white corpuscles of the blood.
We

FIG. 7.  (Drosera rotundifolia.) Diagram of the same cell of a
tentacle, showing the various forms successively assumed by the
aggregated masses of protoplasm.

may, therefore, conclude that they consist of protoplasm. If their
shapes are sketched at intervals of a few minutes, they are invariably
seen to have undergone great changes of form; and the same cell has
been observed for several hours. Eight rude, though accurate sketches
of the same cell, made at intervals of between 2 m. or 3 m., are here
given (fig. 7), and illustrate some of the simpler and commonest
changes. The cell A, when first sketched, included two oval masses of
purple protoplasm touching each other. These became separate, as shown
at B, and then reunited, as at C. After the next interval a very common
appearance was presented-- [page 41] D, namely, the formation of an
extremely minute sphere at one end of an elongated mass.  This rapidly
increased in size, as shown in E, and was then re-absorbed, as at F, by
which time another sphere had been formed at the opposite end.

The cell above figured was from a tentacle of a dark red leaf, which
had caught a small moth, and was examined under water. As I at first
thought that the movements of the masses might be due to the absorption
of water, I placed a fly on a leaf, and when after 18 hrs. all the
tentacles were well inflected, these were examined without being
immersed in water. The cell

FIG. 8.  (Drosera rotundifolia.) Diagram of the same cell of a
tentacle, showing the various forms successively assumed by the
aggregated masses of protoplasm.

here represented (fig. 8) was from this leaf, being sketched eight
times in the course of 15 m.  These sketches exhibit some of the more
remarkable changes which the protoplasm undergoes. At first, there was
at the base of the cell 1, a little mass on a short footstalk, and a
larger mass near the upper end, and these seemed quite separate.
Nevertheless, they may have been connected by a fine and invisible
thread of protoplasm, for on two other occasions, whilst one mass was
rapidly increasing, and another in the same cell rapidly decreasing, I
was able by varying the light and using a high power, to detect a
connecting thread of extreme tenuity, which evidently served as [page
42] the channel of communication between the two. On the other hand,
such connecting threads are sometimes seen to break, and their
extremities then quickly become club-headed. The other sketches in fig.
8 show the forms successively assumed.

Shortly after the purple fluid within the cells has become aggregated,
the little masses float about in a colourless or almost colourless
fluid; and the layer of white granular protoplasm which flows along the
walls can now be seen much more distinctly. The stream flows at an
irregular rate, up one wall and down the opposite one, generally at a
slower rate across the narrow ends of the elongated cells, and so round
and round. But the current sometimes ceases. The movement is often in
waves, and their crests sometimes stretch almost across the whole width
of the cell, and then sink down again. Small spheres of protoplasm,
apparently quite free, are often driven by the current round the cells;
and filaments attached to the central masses are swayed to and fro, as
if struggling to escape. Altogether, one of these cells with the ever
changing central masses, and with the layer of protoplasm flowing round
the walls, presents a wonderful scene of vital activity.

[Many observations were made on the contents of the cells whilst
undergoing the process of aggregation, but I shall detail only a few
cases under different heads. A small portion of a leaf was cut off,
placed under a high power, and the glands very gently pressed under a
compressor. In 15 m. I distinctly saw extremely minute spheres of
protoplasm aggregating themselves in the purple fluid; these rapidly
increased in size, both within the cells of the glands and of the upper
ends of the pedicels. Particles of glass, cork, and cinders were also
placed on the glands of many tentacles; in 1 hr. several of them were
inflected, but after 1 hr.  35 m. there was no aggregation. Other
tentacles with these particles were examined after 8 hrs., and [page
43] now all their cells had undergone aggregation; so had the cells of
the exterior tentacles which had become inflected through the
irritation transmitted from the glands of the disc, on which the
transported particles rested. This was likewise the case with the short
tentacles round the margins of the disc, which had not as yet become
inflected. This latter fact shows that the process of aggregation is
independent of the inflection of the tentacles, of which indeed we have
other and abundant evidence. Again, the exterior tentacles on three
leaves were carefully examined, and found to contain only homogeneous
purple fluid; little bits of thread were then placed on the glands of
three of them, and after 22 hrs. the purple fluid in their cells almost
down to their bases was aggregated into innumerable, spherical,
elongated, or filamentous masses of protoplasm. The bits of thread had
been carried some time previously to the central disc, and this had
caused all the other tentacles to become somewhat inflected; and their
cells had likewise undergone aggregation, which however, it should be
observed, had not as yet extended down to their bases, but was confined
to the cells close beneath the glands.

Not only do repeated touches on the glands* and the contact of minute
particles cause aggregation, but if glands, without being themselves
injured, are cut off from the summits of the pedicels, this induces a
moderate amount of aggregation in the headless tentacles, after they
have become inflected. On the other hand, if glands are suddenly
crushed between pincers, as was tried in six cases, the tentacles seem
paralysed by so great a shock, for they neither become inflected nor
exhibit any signs of aggregation.

Carbonate of Ammonia.--Of all the causes inducing aggregation, that
which, as far as I have seen, acts the quickest, and is the most
powerful, is a solution of carbonate of ammonia.  Whatever its strength
may be, the glands are always affected first, and soon become quite
opaque, so as to appear black. For instance, I placed a leaf in a few
drops of a strong solution, namely, of one part to 146 of water (or 3
grs. to 1 oz.), and observed it under a high power.  All the glands
began to

* Judging from an account of M. Heckel's observations, which I have
only just seen quoted in the 'Gardeners' Chronicle' (Oct. 10, 1874), he
appears to have observed a similar phenomenon in the stamens of
Berberis, after they have been excited by a touch and have moved; for
he says, "the contents of each individual cell are collected together
in the centre of the cavity." [page 44]

darken in 10 s. (seconds); and in 13 s. were conspicuously darker. In 1
m. extremely small spherical masses of protoplasm could be seen arising
in the cells of the pedicels close beneath the glands, as well as in
the cushions on which the long-headed marginal glands rest.  In several
cases the process travelled down the pedicels for a length twice or
thrice as great as that of the glands, in about 10 m. It was
interesting to observe the process momentarily arrested at each
transverse partition between two cells, and then to see the transparent
contents of the cell next below almost flashing into a cloudy mass. In
the lower part of the pedicels, the action proceeded slower, so that it
took about 20 m. before the cells halfway down the long marginal and
submarginal tentacles became aggregated.

We may infer that the carbonate of ammonia is absorbed by the glands,
not only from its action being so rapid, but from its effect being
somewhat different from that of other salts.  As the glands, when
excited, secrete an acid belonging to the acetic series, the carbonate
is probably at once converted into a salt of this series; and we shall
presently see that the acetate of ammonia causes aggregation almost or
quite as energetically as does the carbonate. If a few drops of a
solution of one part of the carbonate to 437 of water (or 1 gr. to 1
oz.) be added to the purple fluid which exudes from crushed tentacles,
or to paper stained by being rubbed with them, the fluid and the paper
are changed into a pale dirty green.  Nevertheless, some purple colour
could still be detected after 1 hr. 30 m. within the glands of a leaf
left in a solution of twice the above strength (viz. 2 grs. to 1 oz.);
and after 24 hrs. the cells of the pedicels close beneath the glands
still contained spheres of protoplasm of a fine purple tint. These
facts show that the ammonia had not entered as a carbonate, for
otherwise the colour would have been discharged. I have, however,
sometimes observed, especially with the long-headed tentacles on the
margins of very pale leaves immersed in a solution, that the glands as
well as the upper cells of the pedicels were discoloured; and in these
cases I presume that the unchanged carbonate had been absorbed. The
appearance above described, of the aggregating process being arrested
for a short time at each transverse partition, impresses the mind with
the idea of matter passing downwards from cell to cell. But as the
cells one beneath the other undergo aggregation when inorganic and
insoluble particles are placed on the glands, the process must be, at
least in these cases, one of molecular change, transmitted from the
glands, [page 45] independently of the absorption of any matter. So it
may possibly be in the case of the carbonate of ammonia. As, however,
the aggregation caused by this salt travels down the tentacles at a
quicker rate than when insoluble particles are placed on the glands, it
is probable that ammonia in some form is absorbed not only by the
glands, but passes down the tentacles.

Having examined a leaf in water, and found the contents of the cells
homogeneous, I placed it in a few drops of a solution of one part of
the carbonate to 437 of water, and attended to the cells immediately
beneath the glands, but did not use a very high power. No aggregation
was visible in 3 m.; but after 15 m. small spheres of protoplasm were
formed, more especially beneath the long-headed marginal glands; the
process, however, in this case took place with unusual slowness. In 25
m. conspicuous spherical masses were present in the cells of the
pedicels for a length about equal to that of the glands; and in 3 hrs.
to that of a third or half of the whole tentacle.

If tentacles with cells containing only very pale pink fluid, and
apparently but little protoplasm, are placed in a few drops of a weak
solution of one part of the carbonate to 4375 of water (1 gr. to 10
oz.), and the highly transparent cells beneath the glands are carefully
observed under a high power, these may be seen first to become slightly
cloudy from the formation of numberless, only just perceptible,
granules, which rapidly grow larger either from coalescence or from
attracting more protoplasm from the surrounding fluid. On one occasion
I chose a singularly pale leaf, and gave it, whilst under the
microscope, a single drop of a stronger solution of one part to 437 of
water; in this case the contents of the cells did not become cloudy,
but after 10 m. minute irregular granules of protoplasm could be
detected, which soon increased into irregular masses and globules of a
greenish or very pale purple tint; but these never formed perfect
spheres, though incessantly changing their shapes and positions.

With moderately red leaves the first effect of a solution of the
carbonate generally is the formation of two or three, or of several,
extremely minute purple spheres which rapidly increase in size. To give
an idea of the rate at which such spheres increase in size, I may
mention that a rather pale purple leaf placed under a slip of glass was
given a drop of a solution of one part to 292 of water, and in 13 m. a
few minute spheres of protoplasm were formed; one of these, after 2
hrs. 30 m., was about two-thirds of the diameter of the cell.  After 4
hrs. 25 m.  [page 46] it nearly equalled the cell in diameter; and a
second sphere about half as large as the first, together with a few
other minute ones, were formed. After 6 hrs. the fluid in which these
spheres floated was almost colourless. After 8 hrs. 35 m. (always
reckoning from the time when the solution was first added) four new
minute spheres had appeared. Next morning, after 22 hrs., there were,
besides the two large spheres, seven smaller ones, floating in
absolutely colourless fluid, in which some flocculent greenish matter
was suspended.

At the commencement of the process of aggregation, more especially in
dark red leaves, the contents of the cells often present a different
appearance, as if the layer of protoplasm (primordial utricle) which
lines the cells had separated itself and shrunk from the walls; an
irregularly shaped purple bag being thus formed. Other fluids, besides
a solution of the carbonate, for instance an infusion of raw meat,
produce this same effect. But the appearance of the primordial utricle
shrinking from the walls is certainly false;* for before giving the
solution, I saw on several occasions that the walls were lined with
colourless flowing protoplasm, and after the bag-like masses were
formed, the protoplasm was still flowing along the walls in a
conspicuous manner, even more so than before. It appeared indeed as if
the stream of protoplasm was strengthened by the action of the
carbonate, but it was impossible to ascertain whether this was really
the case. The bag-like masses, when once formed, soon begin to glide
slowly round the cells, sometimes sending out projections which
separate into little spheres; other spheres appear in the fluid
surrounding the bags, and these travel much more quickly. That the
small spheres are separate is often shown by sometimes one and then
another travelling in advance, and sometimes they revolve round each
other. I have occasionally seen spheres of this kind proceeding up and
down the same side of a cell, instead of round it. The bag-like masses
after a time generally divide into two rounded or oval masses, and
these undergo the changes shown in figs. 7 and 8. At other times
spheres appear within the bags; and these coalesce and separate in an
endless cycle of change.

After leaves have been left for several hours in a solution of the
carbonate, and complete aggregation has been effected, the

* With other plants I have often seen what appears to be a true
shrinking of the primordial utricle from the walls of the cells, caused
by a solution of carbonate of ammonia, as likewise follows from
mechanical injuries.  [page 47]

stream of protoplasm on the walls of the cells ceases to be visible; I
observed this fact repeatedly, but will give only one instance. A pale
purple leaf was placed in a few drops of a solution of one part to 292
of water, and in 2 hrs. some fine purple spheres were formed in the
upper cells of the pedicels, the stream of protoplasm round their walls
being still quite distinct; but after an additional 4 hrs., during
which time many more spheres were formed, the stream was no longer
distinguishable on the most careful examination; and this no doubt was
due to the contained granules having become united with the spheres, so
that nothing was left by which the movement of the limpid protoplasm
could be perceived. But minute free spheres still travelled up and down
the cells, showing that there was still a current. So it was next
morning, after 22 hrs., by which time some new minute spheres had been
formed; these oscillated from side to side and changed their positions,
proving that the current had not ceased, though no stream of protoplasm
was visible. On another occasion, however, a stream was seen flowing
round the cell-walls of a vigorous, dark-coloured leaf, after it had
been left for 24 hrs. in a rather stronger solution, namely, of one
part of the carbonate to 218 of water. This leaf, therefore, was not
much or at all injured by an immersion for this length of time in the
above solution of two grains to the ounce; and on being afterwards left
for 24 hrs. in water, the aggregated masses in many of the cells were
re-dissolved, in the same manner as occurs with leaves in a state of
nature when they re-expand after having caught insects.

In a leaf which had been left for 22 hrs. in a solution of one part of
the carbonate to 292 of water, some spheres of protoplasm (formed by
the self-division of a bag-like mass) were gently pressed beneath a
covering glass, and then examined under a high power. They were now
distinctly divided by well-defined radiating fissures, or were broken
up into separate fragments with sharp edges; and they were solid to the
centre. In the larger broken spheres the central part was more opaque,
darker-coloured, and less brittle than the exterior; the latter alone
being in some cases penetrated by the fissures. In many of the spheres
the line of separation between the outer and inner parts was tolerably
well defined. The outer parts were of exactly the same very pale purple
tint, as that of the last formed smaller spheres; and these latter did
not include any darker central core.

From these several facts we may conclude that when vigorous
dark-coloured leaves are subjected to the action of carbonate of [page
48] ammonia, the fluid within the cells of the tentacles often
aggregates exteriorly into coherent viscid matter, forming a kind of
bag. Small spheres sometimes appear within this bag, and the whole
generally soon divides into two or more spheres, which repeatedly
coalesce and redivide. After a longer or shorter time the granules in
the colourless layer of protoplasm, which flows round the walls, are
drawn to and unite with the larger spheres, or form small independent
spheres; these latter being of a much paler colour, and more brittle
than the first aggregated masses. After the granules of protoplasm have
been thus attracted, the layer of flowing protoplasm can no longer be
distinguished, though a current of limpid fluid still flows round the
walls.

If a leaf is immersed in a very strong, almost concentrated, solution
of carbonate of ammonia, the glands are instantly blackened, and they
secrete copiously; but no movement of the tentacles ensues. Two leaves
thus treated became after 1 hr. flaccid, and seemed killed; all the
cells in their tentacles contained spheres of protoplasm, but these
were small and discoloured. Two other leaves were placed in a solution
not quite so strong, and there was well-marked aggregation in 30 m.
After 24 hrs. the spherical or more commonly oblong masses of
protoplasm became opaque and granular, instead of being as usual
translucent; and in the lower cells there were only innumerable minute
spherical granules. It was evident that the strength of the solution
had interfered with the completion of the process, as we shall see
likewise follows from too great heat.

All the foregoing observations relate to the exterior tentacles, which
are of a purple colour; but the green pedicels of the short central
tentacles are acted on by the carbonate, and by an infusion of raw
meat, in exactly the same manner, with the sole difference that the
aggregated masses are of a greenish colour; so that the process is in
no way dependent on the colour of the fluid within the cells.

Finally, the most remarkable fact with respect to this salt is the
extraordinary small amount which suffices to cause aggregation. Full
details will be given in the seventh chapter, and here it will be
enough to say that with a sensitive leaf the absorption by a gland of
1/134400 of a grain (.000482 mgr.) is enough to cause in the course of
one hour well-marked aggregation in the cells immediately beneath the
gland.

The Effects of certain other Salts and Fluids.--Two leaves were placed
in a solution of one part of acetate of ammonia to about [page 49] 146
of water, and were acted on quite as energetically, but perhaps not
quite so quickly, as by the carbonate. After 10 m. the glands were
black, and in the cells beneath them there were traces of aggregation,
which after 15 m. was well marked, extending down the tentacles for a
length equal to that of the glands. After 2 hrs. the contents of almost
all the cells in all the tentacles were broken up into masses of
protoplasm. A leaf was immersed in a solution of one part of oxalate of
ammonia to 146 of water; and after 24 m. some, but not a conspicuous,
change could be seen within the cells beneath the glands. After 47 m.
plenty of spherical masses of protoplasm were formed, and these
extended down the tentacles for about the length of the glands. This
salt, therefore, does not act so quickly as the carbonate. With respect
to the citrate of ammonia, a leaf was placed in a little solution of
the above strength, and there was not even a trace of aggregation in
the cells beneath the glands, until 56 m. had elapsed; but it was well
marked after 2 hrs. 20 m. On another occasion a leaf was placed in a
stronger solution, of one part of the citrate to 109 of water (4 grs.
to 1 oz.), and at the same time another leaf in a solution of the
carbonate of the same strength. The glands of the latter were blackened
in less than 2 m., and after 1 hr. 45 m. the aggregated masses, which
were spherical and very dark-coloured, extended down all the tentacles,
for between half and two-thirds of their lengths; whereas in the leaf
immersed in the citrate the glands, after 30 m., were of a dark red,
and the aggregated masses in the cells beneath them pink and
elongated.  After 1 hr. 45 m. these masses extended down for only about
one-fifth or one-fourth of the length of the tentacles.

Two leaves were placed, each in ten minims of a solution of one part of
nitrate of ammonia to 5250 of water (1 gr. to 12 oz.), so that each
leaf received 1/576 of a grain (.1124 mgr.).  This quantity caused all
the tentacles to be inflected, but after 24 hrs. there was only a trace
of aggregation. One of these same leaves was then placed in a weak
solution of the carbonate, and after 1 hr. 45 m. the tentacles for half
their lengths showed an astonishing degree of aggregation. Two other
leaves were then placed in a much stronger solution of one part of the
nitrate to 146 of water (3 grs. to 1 oz.); in one of these there was no
marked change after 3 hrs.; but in the other there was a trace of
aggregation after 52 m., and this was plainly marked after 1 hr. 22 m.,
but even after 2 hrs. 12 m. there was certainly not more aggregation
than would have fol- [page 50] lowed from an immersion of from 5 m. to
10 m. in an equally strong solution of the carbonate.

Lastly, a leaf was placed in thirty minims of a solution of one part of
phosphate of ammonia to 43,750 of water (1 gr. to 100 oz.), so that it
received 1/1600 of a grain (.04079 mgr.); this soon caused the
tentacles to be strongly inflected; and after 24 hrs. the contents of
the cells were aggregated into oval and irregularly globular masses,
with a conspicuous current of protoplasm flowing round the walls. But
after so long an interval aggregation would have ensued, whatever had
caused inflection.

Only a few other salts, besides those of ammonia, were tried in
relation to the process of aggregation. A leaf was placed in a solution
of one part of chloride of sodium to 218 of water, and after 1 hr. the
contents of the cells were aggregated into small, irregularly globular,
brownish masses; these after 2 hrs. were almost disintegrated and
pulpy. It was evident that the protoplasm had been injuriously
affected; and soon afterwards some of the cells appeared quite empty.
These effects differ altogether from those produced by the several
salts of ammonia, as well as by various organic fluids, and by
inorganic particles placed on the glands. A solution of the same
strength of carbonate of soda and carbonate of potash acted in nearly
the same manner as the chloride; and here again, after 2 hrs. 30 m.,
the outer cells of some of the glands had emptied themselves of their
brown pulpy contents. We shall see in the eighth chapter that solutions
of several salts of soda of half the above strength cause inflection,
but do not injure the leaves. Weak solutions of sulphate of quinine, of
nicotine, camphor, poison of the cobra, &c., soon induce well-marked
aggregation; whereas certain other substances (for instance, a solution
of curare) have no such tendency.

Many acids, though much diluted, are poisonous; and though, as will be
shown in the eighth chapter, they cause the tentacles to bend, they do
not excite true aggregation. Thus leaves were placed in a solution of
one part of benzoic acid to 437 of water; and in 15 m. the purple fluid
within the cells had shrunk a little from the walls, yet when carefully
examined after 1 hr. 20 m., there was no true aggregation; and after 24
hrs. the leaf was evidently dead. Other leaves in iodic acid, diluted
to the same degree, showed after 2 hrs. 15 m. the same shrunken
appearance of the purple fluid within the cells; and these, after 6
hrs. 15 m., were seen under a high power to be filled with excessively
minute spheres of dull reddish protoplasm, [page 51] which by the next
morning, after 24 hrs., had almost disappeared, the leaf being
evidently dead. Nor was there any true aggregation in leaves immersed
in propionic acid of the same strength; but in this case the protoplasm
was collected in irregular masses towards the bases of the lower cells
of the tentacles.

A filtered infusion of raw meat induces strong aggregation, but not
very quickly. In one leaf thus immersed there was a little aggregation
after 1 hr. 20 m., and in another after 1 hr. 50 m.  With other leaves
a considerably longer time was required: for instance, one immersed for
5 hrs. showed no aggregation, but was plainly acted on in 5 m.; when
placed in a few drops of a solution of one part of carbonate of ammonia
to 146 of water. Some leaves were left in the infusion for 24 hrs., and
these became aggregated to a wonderful degree, so that the inflected
tentacles presented to the naked eye a plainly mottled appearance. The
little masses of purple protoplasm were generally oval or beaded, and
not nearly so often spherical as in the case of leaves subjected to
carbonate of ammonia. They underwent incessant changes of form; and the
current of colourless protoplasm round the walls was conspicuously
plain after an immersion of 25 hrs. Raw meat is too powerful a
stimulant, and even small bits generally injure, and sometimes kill,
the leaves to which they are given: the aggregated masses of protoplasm
become dingy or almost colourless, and present an unusual granular
appearance, as is likewise the case with leaves which have been
immersed in a very strong solution of carbonate of ammonia. A leaf
placed in milk had the contents of its cells somewhat aggregated in 1
hr. Two other leaves, one immersed in human saliva for 2 hrs. 30 m.,
and another in unboiled white of egg for 1 hr. 30 m., were not action
on in this manner; though they undoubtedly would have been so, had more
time been allowed. These same two leaves, on being afterwards placed in
a solution of carbonate of ammonia (3 grs. to 1 oz.), had their cells
aggregated, the one in 10 m. and the other in 5 m.

Several leaves were left for 4 hrs. 30 m. in a solution of one part of
white sugar to 146 of water, and no aggregation ensued; on being placed
in a solution of this same strength of carbonate of ammonia, they were
acted on in 5 m.; as was likewise a leaf which had been left for 1 hr.
45 m. in a moderately thick solution of gum arabic. Several other
leaves were immersed for some hours in denser solutions of sugar, gum,
and starch, and they had the contents of their cells greatly
aggregated. This [page 52] effect may be attributed to exosmose; for
the leaves in the syrup became quite flaccid, and those in the gum and
starch somewhat flaccid, with their tentacles twisted about in the most
irregular manner, the longer ones like corkscrews. We shall hereafter
see that solutions of these substances, when placed on the discs of
leaves, do not incite inflection. Particles of soft sugar were added to
the secretion round several glands and were soon dissolved, causing a
great increase of the secretion, no doubt by exosmose; and after 24
hrs. the cells showed a certain amount of aggregation, though the
tentacles were not inflected. Glycerine causes in a few minutes
well-pronounced aggregation, commencing as usual within the glands and
then travelling down the tentacles; and this I presume may be
attributed to the strong attraction of this substance for water.
Immersion for several hours in water causes some degree of aggregation.
Twenty leaves were first carefully examined, and re-examined after
having been left immersed in distilled water for various periods, with
the following results. It is rare to find even a trace of aggregation
until 4 or 5 and generally not until several more hours have elapsed.
When however a leaf becomes quickly inflected in water, as sometimes
happens, especially during very warm weather, aggregation may occur in
little over 1 hr. In all cases leaves left in water for more than 24
hrs. have their glands blackened, which shows that their contents are
aggregated; and in the specimens which were carefully examined, there
was fairly well-marked aggregation in the upper cells of the pedicels.
These trials were made with cut off-leaves, and it occurred to me that
this circumstance might influence the result, as the footstalks would
not perhaps absorb water quickly enough to supply the glands as they
continued to secrete. But this view was proved erroneous, for a plant
with uninjured roots, bearing four leaves, was submerged in distilled
water for 47 hrs., and the glands were blackened, though the tentacles
were very little inflected. In one of these leaves there was only a
slight degree of aggregation in the tentacles; in the second rather
more, the purple contents of the cells being a little separated from
the walls; in the third and fourth, which were pale leaves, the
aggregation in the upper parts of the pedicels was well marked. In
these leaves the little masses of protoplasm, many of which were oval,
slowly changed their forms and positions; so that a submergence for 47
hrs. had not killed the protoplasm. In a previous trial with a
submerged plant, the tentacles were not in the least inflected.  [page
53]

Heat induces aggregation. A leaf, with the cells of the tentacles
containing only homogeneous fluid, was waved about for 1 m. in water at
130o Fahr. (54o.4 Cent.) and was then examined under the microscope as
quickly as possible, that is in 2 m. or 3 m.; and by this time the
contents of the cells had undergone some degree of aggregation. A
second leaf was waved for 2 m. in water at 125o (51o.6 Cent.) and
quickly examined as before; the tentacles were well inflected; the
purple fluid in all the cells had shrunk a little from the walls, and
contained many oval and elongated masses of protoplasm, with a few
minute spheres. A third leaf was left in water at 125o, until it
cooled, and when examined after 1 hr.  45 m., the inflected tentacles
showed some aggregation, which became after 3 hrs. more strongly
marked, but did not subsequently increase. Lastly, a leaf was waved for
1 m. in water at 120o (48o.8 Cent.) and then left for 1 hr. 26 m. in
cold water; the tentacles were but little inflected, and there was only
here and there a trace of aggregation. In all these and other trials
with warm water the protoplasm showed much less tendency to aggregate
into spherical masses than when excited by carbonate of ammonia.

Redissolution of the Aggregated Masses of Protoplasm.--As soon as
tentacles which have clasped an insect or any inorganic object, or have
been in any way excited, have fully re-expanded, the aggregated masses
of protoplasm are redissolved and disappear; the cells being now
refilled with homogeneous purple fluid as they were before the
tentacles were inflected. The process of redissolution in all cases
commences at the bases of the tentacles, and proceeds up them towards
the glands. In old leaves, however, especially in those which have been
several times in action, the protoplasm in the uppermost cells of the
pedicels remains in a permanently more or less aggregated condition. In
order to observe the process of redissolution, the following
observations were made: a leaf was left for 24 hrs. in a little
solution of one part of carbonate of ammonia to 218 of water, and the
protoplasm was as usual aggregated into numberless purple spheres,
which were incessantly changing their forms. The leaf was then washed
and placed in distilled water, and after 3 hrs. 15 m. some few of the
spheres began to show by their less clearly defined edges signs of
redissolution.  After 9 hrs. many of them had become elongated, and the
surrounding fluid in the cells was slightly more coloured, showing
plainly that redissolution had commenced. After 24 hrs., though many
cells still contained spheres, here and there one [page 54] could be
seen filled with purple fluid, without a vestige of aggregated
protoplasm; the whole having been redissolved. A leaf with aggregated
masses, caused by its having been waved for 2 m. in water at the
temperature of 125o Fahr., was left in cold water, and after 11 hrs.
the protoplasm showed traces of incipient redissolution. When again
examined three days after its immersion in the warm water, there was a
conspicuous difference, though the protoplasm was still somewhat
aggregated. Another leaf, with the contents of all the cells strongly
aggregated from the action of a weak solution of phosphate of ammonia,
was left for between three and four days in a mixture (known to be
innocuous) of one drachm of alcohol to eight drachms of water, and when
re-examined every trace of aggregation had disappeared, the cells being
now filled with homogeneous fluid.

We have seen that leaves immersed for some hours in dense solutions of
sugar, gum, and starch, have the contents of their cells greatly
aggregated, and are rendered more or less flaccid, with the tentacles
irregularly contorted. These leaves, after being left for four days in
distilled water, became less flaccid, with their tentacles partially
re-expanded, and the aggregated masses of protoplasm were partially
redissolved. A leaf with its tentacles closely clasped over a fly, and
with the contents of the cells strongly aggregated, was placed in a
little sherry wine; after 2 hrs. several of the tentacles had
re-expanded, and the others could by a mere touch be pushed back into
their properly expanded positions, and now all traces of aggregation
had disappeared, the cells being filled with perfectly homogeneous pink
fluid.  The redissolution in these cases may, I presume, be attributed
to endosmose.]

     On the Proximate Causes of the Process of Aggregation.

As most of the stimulants which cause the inflection of the tentacles
likewise induce aggregation in the contents of their cells, this latter
process might be thought to be the direct result of inflection; but
this is not the case. If leaves are placed in rather strong solutions
of carbonate of ammonia, for instance of three or four, and even
sometimes of only two grains to the ounce of water (i.e. one part to
109, or 146, or [page 55] 218, of water), the tentacles are paralysed,
and do not become inflected, yet they soon exhibit strongly marked
aggregation. Moreover, the short central tentacles of a leaf which has
been immersed in a weak solution of any salt of ammonia, or in any
nitrogenous organic fluid, do not become in the least inflected;
nevertheless they exhibit all the phenomena of aggregation.  On the
other hand, several acids cause strongly pronounced inflection, but no
aggregation.

It is an important fact that when an organic or inorganic object is
placed on the glands of the disc, and the exterior tentacles are thus
caused to bend inwards, not only is the secretion from the glands of
the latter increased in quantity and rendered acid, but the contents of
the cells of their pedicels become aggregated. The process always
commences in the glands, although these have not as yet touched any
object. Some force or influence must, therefore, be transmitted from
the central glands to the exterior tentacles, first to near their bases
causing this part to bend, and next to the glands causing them to
secrete more copiously. After a short time the glands, thus indirectly
excited, transmit or reflect some influence down their own pedicels,
inducing aggregation in cell beneath cell to their bases.

It seems at first sight a probable view that aggregation is due to the
glands being excited to secrete more copiously, so that sufficient
fluid is not left in their cells, and in the cells of the pedicels, to
hold the protoplasm in solution. In favour of this view is the fact
that aggregation follows the inflection of the tentacles, and during
the movement the glands generally, or, as I believe, always, secrete
more copiously than they did before. Again, during the re-expansion
[page 56] of the tentacles, the glands secrete less freely, or quite
cease to secrete, and the aggregated masses of protoplasm are then
redissolved. Moreover, when leaves are immersed in dense vegetable
solutions, or in glycerine, the fluid within the gland-cells passes
outwards, and there is aggregation; and when the leaves are afterwards
immersed in water, or in an innocuous fluid of less specific gravity
than water, the protoplasm is redissolved, and this, no doubt, is due
to endosmose.

Opposed to this view, that aggregation is caused by the outward passage
of fluid from the cells, are the following facts. There seems no close
relation between the degree of increased secretion and that of
aggregation. Thus a particle of sugar added to the secretion round a
gland causes a much greater increase of secretion, and much less
aggregation, than does a particle of carbonate of ammonia given in the
same manner. It does not appear probable that pure water would cause
much exosmose, and yet aggregation often follows from an immersion in
water of between 16 hrs. and 24 hrs., and always after from 24 hrs. to
48 hrs.  Still less probable is it that water at a temperature of from
125o to 130o Fahr. (51o.6 to 54o.4 Cent.) should cause fluid to pass,
not only from the glands, but from all the cells of the tentacles down
to their bases, so quickly that aggregation is induced within 2 m. or 3
m.  Another strong argument against this view is, that, after complete
aggregation, the spheres and oval masses of protoplasm float about in
an abundant supply of thin colourless fluid; so that at least the
latter stages of the process cannot be due to the want of fluid to hold
the protoplasm in solution. There is still stronger evidence that
aggregation is independent of secretion; for the papillae, described in
the first chapter, with which the [page 57] leaves are studded are not
glandular, and do not secrete, yet they rapidly absorb carbonate of
ammonia or an infusion of raw meat, and their contents then quickly
undergo aggregation, which afterwards spreads into the cells of the
surrounding tissues. We shall hereafter see that the purple fluid
within the sensitive filaments of Dionaea, which do not secrete,
likewise undergoes aggregation from the action of a weak solution of
carbonate of ammonia.

The process of aggregation is a vital one; by which I mean that the
contents of the cells must be alive and uninjured to be thus affected,
and they must be in an oxygenated condition for the transmission of the
process at the proper rate. Some tentacles in a drop of water were
strongly pressed beneath a slip of glass; many of the cells were
ruptured, and pulpy matter of a purple colour, with granules of all
sizes and shapes, exuded, but hardly any of the cells were completely
emptied. I then added a minute drop of a solution of one part of
carbonate of ammonia to 109 of water, and after 1 hr. examined the
specimens. Here and there a few cells, both in the glands and in the
pedicels, had escaped being ruptured, and their contents were well
aggregated into spheres which were constantly changing their forms and
positions, and a current could still be seen flowing along the walls;
so that the protoplasm was alive. On the other hand, the exuded matter,
which was now almost colourless instead of being purple, did not
exhibit a trace of aggregation. Nor was there a trace in the many cells
which were ruptured, but which had not been completely emptied of their
contents. Though I looked carefully, no signs of a current could be
seen within these ruptured cells. They had evidently been killed by the
pressure; and the matter which they [page 58] still contained did not
undergo aggregation any more than that which had exuded. In these
specimens, as I may add, the individuality of the life of each cell was
well illustrated.

A full account will be given in the next chapter of the effects of heat
on the leaves, and I need here only state that leaves immersed for a
short time in water at a temperature of 120oFahr. (48o.8 Cent.), which,
as we have seen, does not immediately induce aggregation, were then
placed in a few drops of a strong solution of one part of carbonate of
ammonia to 109 of water, and became finely aggregated. On the other
hand, leaves, after an immersion in water at 150o (65o.5 Cent.), on
being placed in the same strong solution, did not undergo aggregation,
the cells becoming filled with brownish, pulpy, or muddy matter. With
leaves subjected to temperatures between these two extremes of 120o and
150o Fahr. (48o.8 and 65o.5 Cent.), there were gradations in the
completeness of the process; the former temperature not preventing
aggregation from the subsequent action of carbonate of ammonia, the
latter quite stopping it. Thus, leaves immersed in water, heated to
130o (54o.4 Cent.), and then in the solution, formed perfectly defined
spheres, but these were decidedly smaller than in ordinary cases. With
other leaves heated to 140o (60o Cent.), the spheres were extremely
small, yet well defined, but many of the cells contained, in addition,
some brownish pulpy matter. In two cases of leaves heated to 145o
(62o.7 Cent.), a few tentacles could be found with some of their cells
containing a few minute spheres; whilst the other cells and other whole
tentacles included only the brownish, disintegrated or pulpy matter.

The fluid within the cells of the tentacles must be in an oxygenated
condition, in order that the force or [page 59] influence which induces
aggregation should be transmitted at the proper rate from cell to cell.
A plant, with its roots in water, was left for 45 m. in a vessel
containing 122 oz. of carbonic acid. A leaf from this plant, and, for
comparison, one from a fresh plant, were both immersed for 1 hr. in a
rather strong solution of carbonate of ammonia. They were then
compared, and certainly there was much less aggregation in the leaf
which had been subjected to the carbonic acid than in the other.
Another plant was exposed in the same vessel for 2 hrs. to carbonic
acid, and one of its leaves was then placed in a solution of one part
of the carbonate to 437 of water; the glands were instantly blackened,
showing that they had absorbed, and that their contents were
aggregated; but in the cells close beneath the glands there was no
aggregation even after an interval of 3 hrs. After 4 hrs. 15 m. a few
minute spheres of protoplasm were formed in these cells, but even after
5 hrs. 30 m. the aggregation did not extend down the pedicels for a
length equal to that of the glands. After numberless trials with fresh
leaves immersed in a solution of this strength, I have never seen the
aggregating action transmitted at nearly so slow a rate. Another plant
was left for 2 hrs. in carbonic acid, but was then exposed for 20 m. to
the open air, during which time the leaves, being of a red colour,
would have absorbed some oxygen. One of them, as well as a fresh leaf
for comparison, were now immersed in the same solution as before. The
former were looked at repeatedly, and after an interval of 65 m. a few
spheres of protoplasm were first observed in the cells close beneath
the glands, but only in two or three of the longer tentacles. After 3
hrs. the aggregation had travelled down the pedicels of a few of the
tentacles [page 60] for a length equal to that of the glands. On the
other hand, in the fresh leaf similarly treated, aggregation was plain
in many of the tentacles after 15 m.; after 65 m. it had extended down
the pedicels for four, five, or more times the lengths of the glands;
and after 3 hrs. the cells of all the tentacles were affected for
one-third or one-half of their entire lengths. Hence there can be no
doubt that the exposure of leaves to carbonic acid either stops for a
time the process of aggregation, or checks the transmission of the
proper influence when the glands are subsequently excited by carbonate
of ammonia; and this substance acts more promptly and energetically
than any other. It is known that the protoplasm of plants exhibits its
spontaneous movements only as long as it is in an oxygenated condition;
and so it is with the white corpuscles of the blood, only as long as
they receive oxygen from the red corpuscles;* but the cases above given
are somewhat different, as they relate to the delay in the generation
or aggregation of the masses of protoplasm by the exclusion of oxygen.

Summary and Concluding Remarks.--The process of aggregation is
independent of the inflection of the tentacles and of increased
secretion from the glands. It commences within the glands, whether
these have been directly excited, or indirectly by a stimulus received
from other glands. In both cases the process is transmitted from cell
to cell down the whole length of the tentacles, being arrested for a
short time at each transverse partition. With pale-coloured leaves the
first change which is perceptible, but only

* With respect to plants, Sachs, 'Trait de Bot.' 3rd edit., 1874, p.
864. On blood corpuscles, see 'Quarterly Journal of Microscopical
Science,' April 1874, p. 185.' [page 61]

under a high power, is the appearance of the finest granules in the
fluid within the cells, making it slightly cloudy. These granules soon
aggregate into small globular masses. I have seen a cloud of this kind
appear in 10 s. after a drop of a solution of carbonate of ammonia had
been given to a gland. With dark red leaves the first visible change
often is the conversion of the outer layer of the fluid within the
cells into bag-like masses. The aggregated masses, however they may
have been developed, incessantly change their forms and positions. They
are not filled with fluid, but are solid to their centres. Ultimately
the colourless granules in the protoplasm which flows round the walls
coalesce with the central spheres or masses; but there is still a
current of limpid fluid flowing within the cells. As soon as the
tentacles fully re-expand, the aggregated masses are redissolved, and
the cells become filled with homogeneous purple fluid, as they were at
first. The process of redissolution commences at the bases of the
tentacles, thence proceeding upwards to the glands; and, therefore, in
a reversed direction to that of aggregation.

Aggregation is excited by the most diversified causes,--by the glands
being several times touched,--by the pressure of particles of any kind,
and as these are supported by the dense secretion, they can hardly
press on the glands with the weight of a millionth of a grain,*--by the
tentacles being cut off close beneath

* According to Hofmeister (as quoted by Sachs, 'Trait de Bot.' 1874, p.
958), very slight pressure on the cell-membrane arrests immediately the
movements of the protoplasm, and even determines its separation from
the walls. But the process of aggregation is a different phenomenon, as
it relates to the contents of the cells, and only secondarily to the
layer of protoplasm which flows along the walls; though no doubt the
effects of pressure or of a touch on the outside must be transmitted
through this layer.  [page 62]

the glands,--by the glands absorbing various fluids or matter dissolved
out of certain bodies,--by exosmose,--and by a certain degree of heat.
On the other hand, a temperature of about 150o Fahr. (65o.5 Cent.) does
not excite aggregation; nor does the sudden crushing of a gland. If a
cell is ruptured, neither the exuded matter nor that which still
remains within the cell undergoes aggregation when carbonate of ammonia
is added. A very strong solution of this salt and rather large bits of
raw meat prevent the aggregated masses being well developed. From these
facts we may conclude that the protoplasmic fluid within a cell does
not become aggregated unless it be in a living state, and only
imperfectly if the cell has been injured. We have also seen that the
fluid must be in an oxygenated state, in order that the process of
aggregation should travel from cell to cell at the proper rate.

Various nitrogenous organic fluids and salts of ammonia induce
aggregation, but in different degrees and at very different rates.
Carbonate of ammonia is the most powerful of all known substances; the
absorption of 1/134400 of a grain (.000482 mg.) by a gland suffices to
cause all the cells of the same tentacle to become aggregated. The
first effect of the carbonate and of certain other salts of ammonia, as
well as of some other fluids, is the darkening or blackening of the
glands. This follows even from long immersion in cold distilled water.
It apparently depends in chief part on the strong aggregation of their
cell-contents, which thus become opaque, and do not reflect light. Some
other fluids render the glands of a brighter red; whilst certain acids,
though much diluted, the poison of the cobra-snake, &c., make the
glands perfectly white and opaque; and this seems to depend on the
coagulation of their contents without [page 63] any aggregation.
Nevertheless, before being thus affected, they are able, at least in
some cases, to excite aggregation in their own tentacles.

That the central glands, if irritated, send centrifugally some
influence to the exterior glands, causing them to send back a
centripetal influence inducing aggregation, is perhaps the most
interesting fact given in this chapter. But the whole process of
aggregation is in itself a striking phenomenon. Whenever the peripheral
extremity of a nerve is touched or pressed, and a sensation is felt, it
is believed that an invisible molecular change is sent from one end of
the nerve to the other; but when a gland of Drosera is repeatedly
touched or gently pressed, we can actually see a molecular change
proceeding from the gland down the tentacle; though this change is
probably of a very different nature from that in a nerve.  Finally, as
so many and such widely different causes excite aggregation, it would
appear that the living matter within the gland-cells is in so unstable
a condition that almost any disturbance suffices to change its
molecular nature, as in the case of certain chemical compounds. And
this change in the glands, whether excited directly, or indirectly by a
stimulus received from other glands, is transmitted from cell to cell,
causing granules of protoplasm either to be actually generated in the
previously limpid fluid or to coalesce and thus to become visible.

Supplementary Observations on the Process of Aggregation in the Roots
of Plants.

It will hereafter be seen that a weak solution of the carbonate of
ammonia induces aggregation in the cells of the roots of Drosera; and
this led me to make a few trials on the roots of other plants. I dug up
in the latter part of October the first weed which I met with, viz.
Euphorbia peplus, being care- [page 64] ful not to injure the roots;
these were washed and placed in a little solution of one part of
carbonate of ammonia to 146 of water. In less than one minute I saw a
cloud travelling from cell to cell up the roots, with wonderful
rapidity. After from 8 m. to 9 m. the fine granules, which caused this
cloudy appearance, became aggregated towards the extremities of the
roots into quadrangular masses of brown matter; and some of these soon
changed their forms and became spherical. Some of the cells, however,
remained unaffected. I repeated the experiment with another plant of
the same species, but before I could get the specimen into focus under
the microscope, clouds of granules and quadrangular masses of reddish
and brown matter were formed, and had run far up all the roots. A fresh
root was now left for 18 hrs. in a drachm of a solution of one part of
the carbonate to 437 of water, so that it received 1/8 of a grain, or
2.024 mg. When examined, the cells of all the roots throughout their
whole length contained aggregated masses of reddish and brown matter.
Before making these experiments, several roots were closely examined,
and not a trace of the cloudy appearance or of the granular masses
could be seen in any of them. Roots were also immersed for 35 m.  in a
solution of one part of carbonate of potash to 218 of water; but this
salt produced no effect.

I may here add that thin slices of the stem of the Euphorbia were
placed in the same solution, and the cells which were green instantly
became cloudy, whilst others which were before colourless were clouded
with brown, owing to the formation of numerous granules of this tint. I
have also seen with various kinds of leaves, left for some time in a
solution of carbonate of ammonia, that the grains of chlorophyll ran
together and partially coalesced; and this seems to be a form of
aggregation.

Plants of duck-weed (Lemna) were left for between 30 m. and 45 m. in a
solution of one part of this same salt to 146 of water, and three of
their roots were then examined. In two of them, all the cells which had
previously contained only limpid fluid now included little green
spheres. After from 1 1/2 hr. to 2 hrs. similar spheres appeared in the
cells on the borders of the leaves; but whether the ammonia had
travelled up the roots or had been directly absorbed by the leaves, I
cannot say. As one species, Lemna arrhiza, produces no roots, the
latter alternative is perhaps the most probable. After about 2 1/2 hrs.
some of the little green spheres in the roots were broken up into small
granules which exhibited Brownian movements. Some duck-weed was also
left for 1 hr. 30 m. in a solution of one part of [page 65] carbonate
of potash to 218 of water, and no decided change could be perceived in
the cells of the roots; but when these same roots were placed for 25 m.
in a solution of carbonate of ammonia of the same strength, little
green spheres were formed.

A green marine alga was left for some time in this same solution, but
was very doubtfully affected. On the other hand, a red marine alga,
with finely pinnated fronds, was strongly affected. The contents of the
cells aggregated themselves into broken rings, still of a red colour,
which very slowly and slightly changed their shapes, and the central
spaces within these rings became cloudy with red granular matter. The
facts here given (whether they are new, I know not) indicate that
interesting results would perhaps be gained by observing the action of
various saline solutions and other fluids on the roots of plants.
[page 66]




                          CHAPTER IV.

               THE EFFECTS OF HEAT ON THE LEAVES.

Nature of the experiments--Effects of boiling water--Warm water causes
rapid inflection-- Water at a higher temperature does not cause
immediate inflection, but does not kill the leaves, as shown by their
subsequent re-expansion and by the aggregation of the protoplasm-- A
still higher temperature kills the leaves and coagulates the albuminous
contents of the glands.

IN my observations on Drosera rotundifolia, the leaves seemed to be
more quickly inflected over animal substances, and to remain inflected
for a longer period during very warm than during cold weather. I
wished, therefore, to ascertain whether heat alone would induce
inflection, and what temperature was the most efficient. Another
interesting point presented itself, namely, at what degree life was
extinguished; for Drosera offers unusual facilities in this respect,
not in the loss of the power of inflection, but in that of subsequent
re-expansion, and more especially in the failure of the protoplasm to
become aggregated, when the leaves after being heated are immersed in a
solution of carbonate of ammonia.*

* When my experiments on the effects of heat were made, I was not aware
that the subject had been carefully investigated by several observers.
For instance, Sachs is convinced ('Trait de Botanique,' 1874, pp. 772,
854) that the most different kinds of plants all perish if kept for 10
m. in water at 45o to 46o Cent., or 113o to 115o Fahr.; and he
concludes that the protoplasm within their cells always coagulates, if
in a damp condition, at a temperature of between 50oand 60o Cent., or
122o to 140o Fahr. Max Schultze and Khne (as quoted by Dr. Bastian in
'Contemp. Review,' 1874, p. 528) "found that the protoplasm of
plant-cells, with which they experimented, was always killed and [[page
67]] altered by a very brief exposure to a temperature of 118 1/2o
Fahr. as a maximum." As my results are deduced from special phenomena,
namely, the subsequent aggregation of the protoplasm and the
re-expansion of the tentacles, they seem to me worth giving. We shall
find that Drosera resists heat somewhat better than most other plants.
That there should be considerable differences in this respect is not
surprising, considering that some low vegetable organisms grow in hot
springs--cases of which have been collected by Prof. Wyman ('American
Journal of Science,' vol. xliv. 1867). Thus, Dr. Hooker found Confervae
in water at 168o Fahr.; Humboldt, at 185o Fahr.; and Descloizeaux, at
208o Fahr.) [page 67]

[My experiments were tried in the following manner. Leaves were cut
off, and this does not in the least interfere with their powers; for
instance, three cut off leaves, with bits of meat placed on them, were
kept in a damp atmosphere, and after 23 hrs. closely embraced the meat
both with their tentacles and blades; and the protoplasm within their
cells was well aggregated. Three ounces of doubly distilled water was
heated in a porcelain vessel, with a delicate thermometer having a long
bulb obliquely suspended in it. The water was gradually raised to the
required temperature by a spirit-lamp moved about under the vessel; and
in all cases the leaves were continually waved for some minutes close
to the bulb. They were then placed in cold water, or in a solution of
carbonate of ammonia. In other cases they were left in the water, which
had been raised to a certain temperature, until it cooled. Again in
other cases the leaves were suddenly plunged into water of a certain
temperature, and kept there for a specified time. Considering that the
tentacles are extremely delicate, and that their coats are very thin,
it seems scarcely possible that the fluid contents of their cells
should not have been heated to within a degree or two of the
temperature of the surrounding water. Any further precautions would, I
think, have been superfluous, as the leaves from age or constitutional
causes differ slightly in their sensitiveness to heat.

It will be convenient first briefly to describe the effects of
immersion for thirty seconds in boiling water. The leaves are rendered
flaccid, with their tentacles bowed backwards, which, as we shall see
in a future chapter, is probably due to their outer surfaces retaining
their elasticity for a longer period than their inner surfaces retain
the power of contraction. The purple fluid within the cells of the
pedicels is rendered finely granular, but there is no true aggregation;
nor does this follow [page 68] when the leaves are subsequently placed
in a solution of carbonate of ammonia. But the most remarkable change
is that the glands become opaque and uniformly white; and this may be
attributed to the coagulation of their albuminous contents.

My first and preliminary experiment consisted in putting seven leaves
in the same vessel of water, and warming it slowly up to the
temperature of 110o Fahr. (43o.3 Cent.); a leaf being taken out as soon
as the temperature rose to 80o (26o.6 Cent.), another at 85o, another
at 90o, and so on. Each leaf, when taken out, was placed in water at
the temperature of my room, and the tentacles of all soon became
slightly, though irregularly, inflected. They were now removed from the
cold water and kept in damp air, with bits of meat placed on their
discs.  The leaf which had been exposed to the temperature of 110o
became in 15 m. greatly inflected; and in 2 hrs. every single tentacle
closely embraced the meat. So it was, but after rather longer
intervals, with the six other leaves. It appears, therefore, that the
warm bath had increased their sensitiveness when excited by meat.

I next observed the degree of inflection which leaves underwent within
stated periods, whilst still immersed in warm water, kept as nearly as
possible at the same temperature; but I will here and elsewhere give
only a few of the many trials made. A leaf was left for 10 m. in water
at 100o (37o.7 Cent.), but no inflection occurred. A second leaf,
however, treated in the same manner, had a few of its exterior
tentacles very slightly inflected in 6 m., and several irregularly but
not closely inflected in 10 m. A third leaf, kept in water at 105o to
106o (40o.5 to 41o.1 Cent.), was very moderately inflected in 6 m. A
fourth leaf, in water at 110o (43o.3 Cent.), was somewhat inflected in
4 m., and considerably so in from 6 to 7 m.

Three leaves were placed in water which was heated rather quickly, and
by the time the temperature rose to 115o-116o (46o.1 to 46o.06 Cent.),
all three were inflected. I then removed the lamp, and in a few minutes
every single tentacle was closely inflected. The protoplasm within the
cells was not killed, for it was seen to be in distinct movement; and
the leaves, having been left in cold water for 20 hrs., re-expanded.
Another leaf was immersed in water at 100o (37.7o Cent.), which was
raised to 120o (48o.8 Cent.); and all the tentacles, except the extreme
marginal ones, soon became closely inflected. The leaf was now placed
in cold water, and in 7 hrs. 30 m. it had partly, and in 10 hrs. fully,
re-expanded. On the following morning it was immersed in a weak
solution of carbonate of [page 69] ammonia, and the glands quickly
became black, with strongly marked aggregation in the tentacles,
showing that the protoplasm was alive, and that the glands had not lost
their power of absorption. Another leaf was placed in water at 110o
(43o.3 Cent.) which was raised to 120o (48o.8 Cent.); and every
tentacle, excepting one, was quickly and closely inflected. This leaf
was now immersed in a few drops of a strong solution of carbonate of
ammonia (one part to 109 of water); in 10 m. all the glands became
intensely black, and in 2 hrs. the protoplasm in the cells of the
pedicels was well aggregated. Another leaf was suddenly plunged, and as
usual waved about, in water at 120o, and the tentacles became inflected
in from 2 m. to 3 m., but only so as to stand at right angles to the
disc. The leaf was now placed in the same solution (viz. one part of
carbonate of ammonia to 109 of water, or 4 grs. to 1 oz., which I will
for the future designate as the strong solution), and when I looked at
it again after the interval of an hour, the glands were blackened, and
there was well-marked aggregation. After an additional interval of 4
hrs. the tentacles had become much more inflected. It deserves notice
that a solution as strong as this never causes inflection in ordinary
cases. Lastly a leaf was suddenly placed in water at 125o (51o.6
Cent.), and was left in it until the water cooled; the tentacles were
rendered of a bright red and soon became inflected. The contents of the
cells underwent some degree of aggregation, which in the course of
three hours increased; but the masses of protoplasm did not become
spherical, as almost always occurs with leaves immersed in a solution
of carbonate of ammonia.]

We learn from these cases that a temperature of from 120o to 125o
(48o.8 to 51o.6 Cent.) excites the tentacles into quick movement, but
does not kill the leaves, as shown either by their subsequent
re-expansion or by the aggregation of the protoplasm. We shall now see
that a temperature of 130o (54o.4 Cent.) is too high to cause immediate
inflection, yet does not kill the leaves.

[Experiment 1.--A leaf was plunged, and as in all cases waved about for
a few minutes, in water at 130o (54o.4 Cent.), but there was no trace
of inflection; it was then placed in cold water, and after an interval
of 15 m. very slow movement was [page 70] distinctly seen in a small
mass of protoplasm in one of the cells of a tentacle.* After a few
hours all the tentacles and the blade became inflected.

Experiment 2.--Another leaf was plunged into water at 130o to 131o, and
as before there was no inflection. After being kept in cold water for
an hour, it was placed in the strong solution of ammonia, and in the
course of 55 m. the tentacles were considerably inflected. The glands,
which before had been rendered of a brighter red, were now blackened.
The protoplasm in the cells of the tentacles was distinctly aggregated;
but the spheres were much smaller than those generated in unheated
leaves when subjected to carbonate of ammonia. After an additional 2
hrs. all the tentacles, excepting six or seven, were closely
inflected.

Experiment 3.--A similar experiment to the last, with exactly the same
results.

Experiment 4.--A fine leaf was placed in water at 100o (37o.7 Cent.),
which was then raised to 145o (62o.7 Cent.). Soon after immersion,
there was, as might have been expected, strong inflection. The leaf was
now removed and left in cold water; but from having been exposed to so
high a temperature, it never re-expanded.

Experiment 5.--Leaf immersed at 130o (54o.4 Cent.), and the water
raised to 145o (62o.7 Cent.), there was no immediate inflection; it was
then placed in cold water, and after 1 hr. 20 m. some of the tentacles
on one side became inflected. This leaf was now placed in the strong
solution, and in 40 m. all the submarginal tentacles were well
inflected, and the glands blackened. After an additional interval of 2
hrs. 45 m. all the tentacles, except eight or ten, were closely
inflected, with their cells exhibiting a slight degree of aggregation;
but the spheres of protoplasm were very small, and the cells of the
exterior tentacles contained some pulpy or disintegrated brownish
matter.

Experiments 6 and 7.--Two leaves were plunged in water at 135o (57o.2
Cent.) which was raised to 145o (62o.7 Cent.); neither became
inflected. One of these, however, after having been left for 31 m. in
cold water, exhibited some slight inflection, which increased after an
additional interval of 1 hr. 45 m., until

* Sachs states ('Trait de Botanique,' 1874, p. 855) that the movements
of the protoplasm in the hairs of a Cucurbita ceased after they were
exposed for 1 m. in water to a temperature of 47o to 48o Cent., or 117o
to 119o Fahr.  [page 71]

all the tentacles, except sixteen or seventeen, were more or less
inflected; but the leaf was so much injured that it never re-expanded.
The other leaf, after having been left for half an hour in cold water,
was put into the strong solution, but no inflection ensued; the glands,
however, were blackened, and in some cells there was a little
aggregation, the spheres of protoplasm being extremely small; in other
cells, especially in the exterior tentacles, there was much
greenish-brown pulpy matter.

Experiment 8.--A leaf was plunged and waved about for a few minutes in
water at 140o (60oCent.), and was then left for half an hour in cold
water, but there was no inflection. It was now placed in the strong
solution, and after 2 hrs. 30 m. the inner submarginal tentacles were
well inflected, with their glands blackened, and some imperfect
aggregation in the cells of the pedicels. Three or four of the glands
were spotted with the white porcelain-like structure, like that
produced by boiling water. I have seen this result in no other instance
after an immersion of only a few minutes in water at so low a
temperature as 140o, and in only one leaf out of four, after a similar
immersion at a temperature of 145o Fahr. On the other hand, with two
leaves, one placed in water at 145o (62o.7 Cent.), and the other in
water at 140o (60oCent.), both being left therein until the water
cooled, the glands of both became white and porcelain-like. So that the
duration of the immersion is an important element in the result.

Experiment 9.--A leaf was placed in water at 140o (60o Cent.), which
was raised to 150o(65o.5 Cent.); there was no inflection; on the
contrary, the outer tentacles were somewhat bowed backwards. The glands
became like porcelain, but some of them were a little mottled with
purple. The bases of the glands were often more affected than their
summits. This leaf having been left in the strong solution did not
undergo any inflection or aggregation.

Experiment 10.--A leaf was plunged in water at 150o to 150 1/2o (65o.5
Cent.); it became somewhat flaccid, with the outer tentacles slightly
reflexed, and the inner ones a little bent inwards, but only towards
their tips; and this latter fact shows that the movement was not one of
true inflection, as the basal part alone normally bends. The tentacles
were as usual rendered of a very bright red, with the glands almost
white like porcelain, yet tinged with pink. The leaf having been placed
in the strong solution, the cell-contents of the tentacles became of a
muddy-brown, with no trace of aggregation.  [page 72]

Experiment 11.--A leaf was immersed in water at 145o (62o.7 Cent.),
which was raised to 156o (68o.8 Cent.). The tentacles became bright red
and somewhat reflexed, with almost all the glands like porcelain; those
on the disc being still pinkish, those near the margin quite white. The
leaf being placed as usual first in cold water and then in the strong
solution, the cells in the tentacles became of a muddy greenish brown,
with the protoplasm not aggregated. Nevertheless, four of the glands
escaped being rendered like porcelain, and the pedicels of these glands
were spirally curled, like a French horn, towards their upper ends; but
this can by no means be considered as a case of true inflection. The
protoplasm within the cells of the twisted portions was aggregated into
distinct though excessively minute purple spheres. This case shows
clearly that the protoplasm, after having been exposed to a high
temperature for a few minutes, is capable of aggregation when
afterwards subjected to the action of carbonate of ammonia, unless the
heat has been sufficient to cause coagulation.]

Concluding Remarks.--As the hair-like tentacles are extremely thin and
have delicate walls, and as the leaves were waved about for some
minutes close to the bulb of the thermometer, it seems scarcely
possible that they should not have been raised very nearly to the
temperature which the instrument indicated. From the eleven last
observations we see that a temperature of 130o (54o.4 Cent.) never
causes the immediate inflection of the tentacles, though a temperature
from 120o to 125o (48o.8 to 51o.6 Cent.) quickly produces this effect.
But the leaves are paralysed only for a time by a temperature of 130o,
as afterwards, whether left in simple water or in a solution of
carbonate of ammonia, they become inflected and their protoplasm
undergoes aggregation. This great difference in the effects of a higher
and lower temperature may be compared with that from immersion in
strong and weak solutions of the salts of ammonia; for the former do
not excite movement, whereas the latter act energetically. A temporary
suspension of the [page 73] power of movement due to heat is called by
Sachs* heat-rigidity; and this in the case of the sensitive-plant
(Mimosa) is induced by its exposure for a few minutes to humid air,
raised to 120o-122o Fahr., or 49o to 50o Cent. It deserves notice that
the leaves of Drosera, after being immersed in water at 130o Fahr., are
excited into movement by a solution of the carbonate so strong that it
would paralyse ordinary leaves and cause no inflection.

The exposure of the leaves for a few minutes even to a temperature of
145o Fahr. (62o.7 Cent.) does not always kill them; as when afterwards
left in cold water, or in a strong solution of carbonate of ammonia,
they generally, though not always, become inflected; and the protoplasm
within their cells undergoes aggregation, though the spheres thus
formed are extremely small, with many of the cells partly filled with
brownish muddy matter. In two instances, when leaves were immersed in
water, at a lower temperature than 130o (54o.4 Cent.), which was then
raised to 145o (62o.7 Cent.), they became during the earlier period of
immersion inflected, but on being afterwards left in cold water were
incapable of re-expansion. Exposure for a few minutes to a temperature
of 145o sometimes causes some few of the more sensitive glands to be
speckled with the porcelain-like appearance; and on one occasion this
occurred at a temperature of 140o (60o Cent.). On another occasion,
when a leaf was placed in water at this temperature of only 140o, and
left therein till the water cooled, every gland became like porcelain.
Exposure for a few minutes to a temperature of 150o (65o.5 Cent.)
generally produces this effect, yet many glands retain a

* 'Trait de Bot.' 1874, p. 1034.  [page 74]

pinkish colour, and many present a speckled appearance. This high
temperature never causes true inflection; on the contrary, the
tentacles commonly become reflexed, though to a less degree than when
immersed in boiling water; and this apparently is due to their passive
power of elasticity. After exposure to a temperature of 150o Fahr., the
protoplasm, if subsequently subjected to carbonate of ammonia, instead
of undergoing aggregation, is converted into disintegrated or pulpy
discoloured matter. In short, the leaves are generally killed by this
degree of heat; but owing to differences of age or constitution, they
vary somewhat in this respect. In one anomalous case, four out of the
many glands on a leaf, which had been immersed in water raised to 156o
(68o.8 Cent.), escaped being rendered porcellanous;* and the protoplasm
in the cells close beneath these glands underwent some slight, though
imperfect, degree of aggregation.

Finally, it is a remarkable fact that the leaves of Drosera
rotundifolia, which flourishes on bleak upland moors throughout Great
Britain, and exists (Hooker) within the Arctic Circle, should be able
to withstand for even a short time immersion in water heated to a
temperature of 145o.

It may be worth adding that immersion in cold

* As the opacity and porcelain-like appearance of the glands is
probably due to the coagulation of the albumen, I may add, on the
authority of Dr. Burdon Sanderson, that albumen coagulates at about
155o, but, in presence of acids, the temperature of coagulation is
lower. The leaves of Drosera contain an acid, and perhaps a difference
in the amount contained may account for the slight differences in the
results above recorded.

  It appears that cold-blooded animals are, as might have been
  expected, far more sensitive to an increase of temperature than is
Drosera. Thus, as I hear from Dr. Burdon Sanderson, a frog begins to be
distressed in water at a temperature of only 85o Fahr. At 95o the
muscles become rigid, and the animal dies in a stiffened condition.
[page 75]

water does not cause any inflection: I suddenly placed four leaves,
taken from plants which had been kept for several days at a high
temperature, generally about 75o Fahr. (23o.8 Cent.), in water at 45o
(7o.2 Cent.), but they were hardly at all affected; not so much as some
other leaves from the same plants, which were at the same time immersed
in water at 75o; for these became in a slight degree inflected.  [page
76]



                           CHAPTER V.

THE EFFECTS OF NON-NITROGENOUS AND NITROGENOUS ORGANIC FLUIDS ON
                          THE LEAVES.

Non-nitrogenous fluids--Solutions of gum arabic--Sugar--Starch--Diluted
alcohol--Olive oil-- Infusion and decoction of tea--Nitrogenous
fluids--Milk--Urine--Liquid albumen--Infusion of raw meat--Impure
mucus--Saliva--Solution of isinglass--Difference in the action of these
two sets of fluids--Decoction of green peas--Decoction and infusion of
cabbage--Decoction of grass leaves.

WHEN, in 1860, I first observed Drosera, and was led to believe that
the leaves absorbed nutritious matter from the insects which they
captured, it seemed to me a good plan to make some preliminary trials
with a few common fluids, containing and not containing nitrogenous
matter; and the results are worth giving.

In all the following cases a drop was allowed to fall from the same
pointed instrument on the centre of the leaf; and by repeated trials
one of these drops was ascertained to be on an average very nearly half
a minim, or 1/960 of a fluid ounce, or .0295 ml. But these measurements
obviously do not pretend to any strict accuracy; moreover, the drops of
the viscid fluids were plainly larger than those of water. Only one
leaf on the same plant was tried, and the plants were collected from
two distant localities. The experiments were made during August and
September. In judging of the effects, one caution is necessary: if a
drop of any adhesive fluid is placed on an old or feeble leaf, the
glands of which have ceased to secrete copiously, the drop sometimes
dries up, especially if the plant [page 77] is kept in a room, and some
of the central and submarginal tentacles are thus drawn together,
giving to them the false appearance of having become inflected. This
sometimes occurs with water, as it is rendered adhesive by mingling
with the viscid secretion. Hence the only safe criterion, and to this
alone I have trusted, is the bending inwards of the exterior tentacles,
which have not been touched by the fluid, or at most only at their
bases. In this case the movement is wholly due to the central glands
having been stimulated by the fluid, and transmitting a motor impulse
to the exterior tentacles. The blade of the leaf likewise often curves
inwards, in the same manner as when an insect or bit of meat is placed
on the disc.  This latter movement is never caused, as far as I have
seen, by the mere drying up of an adhesive fluid and the consequent
drawing together of the tentacles.

First for the non-nitrogenous fluids. As a preliminary trial, drops of
distilled water were placed on between thirty and forty leaves, and no
effect whatever was produced; nevertheless, in some other and rare
cases, a few tentacles became for a short time inflected; but this may
have been caused by the glands having been accidentally touched in
getting the leaves into a proper position. That water should produce no
effect might have been anticipated, as otherwise the leaves would have
been excited into movement by every shower of rain.

[Gum arabic.--Solutions of four degrees of strength were made; one of
six grains to the ounce of water (one part to 73); a second rather
stronger, yet very thin; a third moderately thick, and a fourth so
thick that it would only just drop from a pointed instrument. These
were tried on fourteen leaves; the drops being left on the discs from
24 hrs. to 44 hrs.; generally about [page 78] 30 hrs. Inflection was
never thus caused. It is necessary to try pure gum arabic, for a friend
tried a solution bought ready prepared, and this caused the tentacles
to bend; but he afterwards ascertained that it contained much animal
matter, probably glue.

Sugar.--Drops of a solution of white sugar of three strengths (the
weakest containing one part of sugar to 73 of water) were left on
fourteen leaves from 32 hrs. to 48 hrs.; but no effect was produced.

Starch.--A mixture about as thick as cream was dropped on six leaves
and left on them for 30 hrs., no effect being produced. I am surprised
at this fact, as I believe that the starch of commerce generally
contains a trace of gluten, and this nitrogenous substance causes
inflection, as we shall see in the next chapter.

Alcohol, Diluted.--One part of alcohol was added to seven of water, and
the usual drops were placed on the discs of three leaves. No inflection
ensued in the course of 48 hrs. To ascertain whether these leaves had
been at all injured, bits of meat were placed on them, and after 24
hrs. they were closely inflected. I also put drops of sherry-wine on
three other leaves; no inflection was caused, though two of them seemed
somewhat injured. We shall hereafter see that cut off leaves immersed
in diluted alcohol of the above strength do not become inflected.

Olive Oil.--drops were placed on the discs of eleven leaves, and no
effect was produced in from 24 hrs. to 48 hrs. Four of these leaves
were then tested by bits of meat on their discs, and three of them were
found after 24 hrs. with all their tentacles and blades closely
inflected, whilst the fourth had only a few tentacles inflected. It
will, however, be shown in a future place, that cut off leaves immersed
in olive oil are powerfully affected.

Infusion and Decoction of Tea.--Drops of a strong infusion and
decoction, as well as of a rather weak decoction, of tea were placed on
ten leaves, none of which became inflected. I afterwards tested three
of them by adding bits of meat to the drops which still remained on
their discs, and when I examined them after 24 hrs. they were closely
inflected. The chemical principle of tea, namely theine, was
subsequently tried and produced no effect. The albuminous matter which
the leaves must originally have contained, no doubt, had been rendered
insoluble by their having been completely dried.]

We thus see that, excluding the experiments with water, sixty-one
leaves were tried with drops of the [page 79] above-named
non-nitrogenous fluids; and the tentacles were not in a single case
inflected.

[With respect to nitrogenous fluids, the first which came to hand were
tried. The experiments were made at the same time and in exactly the
same manner as the foregoing. As it was immediately evident that these
fluids produced a great effect, I neglected in most cases to record how
soon the tentacles became inflected. But this always occurred in less
than 24 hrs.; whilst the drops of non-nitrogenous fluids which produced
no effect were observed in every case during a considerably longer
period.

Milk.--Drops were placed on sixteen leaves, and the tentacles of all,
as well as the blades of several, soon became greatly inflected. The
periods were recorded in only three cases, namely, with leaves on which
unusually small drops had been placed. Their tentacles were somewhat
inflected in 45 m.; and after 7 hrs. 45 m. the blades of two were so
much curved inwards that they formed little cups enclosing the drops.
These leaves re-expanded on the third day. On another occasion the
blade of a leaf was much inflected in 5 hrs. after a drop of milk had
been placed on it.

Human Urine.--Drops were placed on twelve leaves, and the tentacles of
all, with a single exception, became greatly inflected. Owing, I
presume, to differences in the chemical nature of the urine on
different occasions, the time required for the movements of the
tentacles varied much, but was always effected in under 24 hrs. In two
instances I recorded that all the exterior tentacles were completely
inflected in 17 hrs., but not the blade of the leaf. In another case
the edges of a leaf, after 25 hrs. 30 m., became so strongly inflected
that it was converted into a cup. The power of urine does not lie in
the urea, which, as we shall hereafter see, is inoperative.

Albumen (fresh from a hen's egg), placed on seven leaves, caused the
tentacles of six of them to be well inflected. In one case the edge of
the leaf itself became much curled in after 20 hrs. The one leaf which
was unaffected remained so for 26 hrs., and was then treated with a
drop of milk, and this caused the tentacles to bend inwards in 12 hrs.

Cold Filtered Infusion of Raw Meat.--This was tried only on a single
leaf, which had most of its outer tentacles and the blade inflected in
19 hrs. During subsequent years, I repeatedly used this infusion to
test leaves which had been experimented [page 80] on with other
substances, and it was found to act most energetically, but as no exact
account of these trials was kept, they are not here introduced.

Mucus.--Thick and thin mucus from the bronchial tubes, placed on three
leaves, caused inflection. A leaf with thin mucus had its marginal
tentacles and blade somewhat curved inward in 5 hrs. 30 m., and greatly
so in 20 hrs. The action of this fluid no doubt is due either to the
saliva or to some albuminous matter* mingled with it, and not, as we
shall see in the next chapter, to mucin or the chemical principle of
mucus.

Saliva.--Human saliva, when evaporated, yields  from 1.14 to 1.19 per
cent. of residue; and this yields 0.25 per cent. of ashes, so that the
proportion of nitrogenous matter which saliva contains must be small.
Nevertheless, drops placed on the discs of eight leaves acted on them
all. In one case all the exterior tentacles, excepting nine, were
inflected in 19 hrs. 30 m.; in another case a few became so in 2 hrs.,
and after 7 hrs. 30 m. all those situated near where the drop lay, as
well as the blade, were acted on. Since making these trials, I have
many scores of times just touched glands with the handle of my scalpel
wetted with saliva, to ascertain whether a leaf was in an active
condition; for this was shown in the course of a few minutes by the
bending inwards of the tentacles. The edible nest of the Chinese
swallow is formed of matter secreted by the salivary glands; two grains
were added to one ounce of distilled water (one part to 218), which was
boiled for several minutes, but did not dissolve the whole. The
usual-sized drops were placed on three leaves, and these in 1 hr. 30 m.
were well, and in 2 hrs. 15 m. closely, inflected.

Isinglass.--Drops of a solution about as thick as milk, and of a still
thicker solution, were placed on eight leaves, and the tentacles of all
became inflected. In one case the exterior tentacles were well curved
in after 6 hrs. 30 m., and the blade of the leaf to a partial extent
after 24 hrs. As saliva acted so efficiently, and yet contains so small
a proportion of nitrogenous matter, I tried how small a quantity of
isinglass would act. One part was dissolved in 218 parts of distilled
water, and drops were placed on four leaves. After 5 hrs.  two of these
were considerably and two moderately inflected; after 22 hrs. the
former were greatly and the latter much more inflected. In the course
of 48 hrs.

* Mucus from the air-passages is said in Marshall, 'Outlines of
Physiology,' vol. ii. 1867, p.  364, to contain some albumen.

 Mller's 'Elements of Physiology,' Eng. Trans. vol. i., p. 514.  [page
81]

from the time when the drops were placed on the leaves, all four had
almost re-expanded.  They were then given little bits of meat, and
these acted more powerfully than the solution.  One part of isinglass
was next dissolved in 437 of water; the fluid thus formed was so thin
that it could not be distinguished from pure water. The usual-sized
drops were placed on seven leaves, each of which thus received 1/960 of
a grain (.0295 mg.). Three of them were observed for 41 hrs., but were
in no way affected; the fourth and fifth had two or three of their
exterior tentacles inflected after 18 hrs.; the sixth had a few more;
and the seventh had in addition the edge of the leaf just perceptibly
curved inwards. The tentacles of the four latter leaves began to
re-expand after an additional interval of only 8 hrs. Hence the 1/960
of a grain of isinglass is sufficient to affect very slightly the more
sensitive or active leaves. On one of the leaves, which had not been
acted on by the weak solution, and on another, which had only two of
its tentacles inflected, drops of the solution as thick as milk were
placed; and next morning, after an interval of 16 hrs., both were found
with all their tentacles strongly inflected.]

Altogether I experimented on sixty-four leaves with the above
nitrogenous fluids, the five leaves tried only with the extremely weak
solution of isinglass not being included, nor the numerous trials
subsequently made, of which no exact account was kept. Of these
sixty-four leaves, sixty-three had their tentacles and often their
blades well inflected. The one which failed was probably too old and
torpid. But to obtain so large a proportion of successful cases, care
must be taken to select young and active leaves. Leaves in this
condition were chosen with equal care for the sixty-one trials with
non-nitrogenous fluids (water not included); and we have seen that not
one of these was in the least affected. We may therefore safely
conclude that in the sixty-four experiments with nitrogenous fluids the
inflection of the exterior tentacles was due to the absorption of [page
82] nitrogenous matter by the glands of the tentacles on the disc.

Some of the leaves which were not affected by the non-nitrogenous
fluids were, as above stated, immediately afterwards tested with bits
of meat, and were thus proved to be in an active condition. But in
addition to these trials, twenty-three of the leaves, with drops of
gum, syrup, or starch, still lying on their discs, which had produced
no effect in the course of between 24 hrs. and 48 hrs., were then
tested with drops of milk, urine, or albumen. Of the twenty-three
leaves thus treated, seventeen had their tentacles, and in some cases
their blades, well inflected; but their powers were somewhat impaired,
for the rate of movement was decidedly slower than when fresh leaves
were treated with these same nitrogenous fluids. This impairment, as
well as the insensibility of six of the leaves, may be attributed to
injury from exosmose, caused by the density of the fluids placed on
their discs.

[The results of a few other experiments with nitrogenous fluids may be
here conveniently given. Decoctions of some vegetables, known to be
rich in nitrogen, were made, and these acted like animal fluids. Thus,
a few green peas were boiled for some time in distilled water, and the
moderately thick decoction thus made was allowed to settle. Drops of
the superincumbent fluid were placed on four leaves, and when these
were looked at after 16 hrs., the tentacles and blades of all were
found strongly inflected. I infer from a remark by Gerhardt* that
legumin is present in peas "in combination with an alkali, forming an
incoagulable solution," and this would mingle with boiling water. I may
mention, in relation to the above and following experiments, that
according to Schiff  certain forms of albumen

* Watts' 'Dictionary of Chemistry,' vol. iii., p. 568.

  'Leons sur la Phys. de la Digestion,' tom. i, p. 379; tom. ii. pp.
  154, 166, on legumin.  [page 83]

exist which are not coagulated by boiling water, but are converted into
soluble peptones.

On three occasions chopped cabbage-leaves* were boiled in distilled
water for 1 hr. or for 1 1/4 hr.; and by decanting the decoction after
it had been allowed to rest, a pale dirty green fluid was obtained. The
usual-sized drops were placed on thirteen leaves. Their tentacles and
blades were inflected after 4 hrs. to a quite extraordinary degree.
Next day the protoplasm within the cells of the tentacles was found
aggregated in the most strongly marked manner. I also touched the
viscid secretion round the glands of several tentacles with minute
drops of the decoction on the head of a small pin, and they became well
inflected in a few minutes.  The fluid proving so powerful, one part
was diluted with three of water, and drops were placed on the discs of
five leaves; and these next morning were so much acted on that their
blades were completely doubled over. We thus see that a decoction of
cabbage-leaves is nearly or quite as potent as an infusion of raw
meat.

About the same quantity of chopped cabbage-leaves and of distilled
water, as in the last experiment, were kept in a vessel for 20 hrs. in
a hot closet, but not heated to near the boiling-point. Drops of this
infusion were placed on four leaves. One of these, after 23 hrs., was
much inflected; a second slightly; a third had only the submarginal
tentacles inflected; and the fourth was not at all affected. The power
of this infusion is therefore very much less than that of the
decoction; and it is clear that the immersion of cabbage-leaves for an
hour in water at the boiling temperature is much more efficient in
extracting matter which excites Drosera than immersion during many
hours in warm water. Perhaps the contents of the cells are protected
(as Schiff remarks with respect to legumin) by the walls being formed
of cellulose, and that until these are ruptured by boiling-water, but
little of the contained albuminous matter is dissolved. We know from
the strong odour of cooked cabbage-leaves that boiling water produces
some chemical change in them, and that they are thus rendered far more
digestible and nutritious to man. It is therefore an interesting

* The leaves of young plants, before the heart is formed, such as were
used by me, contain 2.1 per cent. of albuminous matter, and the outer
leaves of mature plants 1.6 per cent. Watts' 'Dictionary of Chemistry,'
vol. i. p. 653.  [page 84]

fact that water at this temperature extracts matter from them which
excites Drosera to an extraordinary degree.

Grasses contain far less nitrogenous matter than do peas or cabbages.
The leaves and stalks of three common kinds were chopped and boiled for
some time in distilled water. Drops of this decoction (after having
stood for 24 hrs.) were placed on six leaves, and acted in a rather
peculiar manner, of which other instances will be given in the seventh
chapter on the salts of ammonia. After 2 hrs. 30 m. four of the leaves
had their blades greatly inflected, but not their exterior tentacles;
and so it was with all six leaves after 24 hrs. Two days afterwards the
blades, as well as the few submarginal tentacles which had been
inflected, all re-expanded; and much of the fluid on their discs was by
this time absorbed. It appears that the decoction strongly excites the
glands on the disc, causing the blade to be quickly and greatly
inflected; but that the stimulus, differently from what occurs in
ordinary cases, does not spread, or only in a feeble degree, to the
exterior tentacles.

I may here add that one part of the extract of belladonna (procured
from a druggist) was dissolved in 437 of water, and drops were placed
on six leaves. Next day all six were somewhat inflected, and after 48
hrs. were completely re-expanded. It was not the included atropine
which produced this effect, for I subsequently ascertained that it is
quite powerless. I also procured some extract of hyoscyamus from three
shops, and made infusions of the same strength as before. Of these
three infusions, only one acted on some of the leaves, which were
tried. Though druggists believe that all the albumen is precipitated in
the preparation of these drugs, I cannot doubt that some is
occasionally retained; and a trace would be sufficient to excite the
more sensitive leaves of Drosera.  [page 85]



                          CHAPTER VI.

        THE DIGESTIVE POWER OF THE SECRETION OF DROSERA.

The secretion rendered acid by the direct and indirect excitement of
the glands--Nature of the acid--Digestible substances--Albumen, its
digestion arrested by alkalies, recommences by the addition of an
acid--Meat--Fibrin--Syntonin--Areolar
tissue--Cartilage--Fibro-cartilage-- Bone--Enamel and
dentine--Phosphate of lime--Fibrous basis of bone--Gelatine--Chondrin--
Milk, casein and
cheese--Gluten--Legumin--Pollen--Globulin--Haematin--Indigestible
substances--Epidermic productions--Fibro-elastic
tissue--Mucin--Pepsin--Urea--Chitine--
Cellulose--Gun-cotton--Chlorophyll--Fat and oil--Starch--Action of the
secretion on living seeds--Summary and concluding remarks.

AS we have seen that nitrogenous fluids act very differently on the
leaves of Drosera from non-nitrogenous fluids, and as the leaves remain
clasped for a much longer time over various organic bodies than over
inorganic bodies, such as bits of glass, cinder, wood, &c., it becomes
an interesting inquiry, whether they can only absorb matter already in
solution, or render it soluble,--that is, have the power of digestion.
We shall immediately see that they certainly have this power, and that
they act on albuminous compounds in exactly the same manner as does the
gastric juice of mammals; the digested matter being afterwards
absorbed.  This fact, which will be clearly proved, is a wonderful one
in the physiology of plants. I must here state that I have been aided
throughout all my later experiments by many valuable suggestions and
assistance given me with the greatest kindness by Dr. Burdon
Sanderson.  [page 86]

It may be well to premise for the sake of any reader who knows nothing
about the digestion of albuminous compounds by animals that this is
effected by means of a ferment, pepsin, together with weak hydrochloric
acid, though almost any acid will serve. Yet neither pepsin nor an acid
by itself has any such power.* We have seen that when the glands of the
disc are excited by the contact of any object, especially of one
containing nitrogenous matter, the outer tentacles and often the blade
become inflected; the leaf being thus converted into a temporary cup or
stomach. At the same time the discal glands secrete more copiously, and
the secretion becomes acid. Moreover, they transmit some influence to
the glands of the exterior tentacles, causing them to pour forth a more
copious secretion, which also becomes acid or more acid than it was
before.

As this result is an important one, I will give the evidence. The
secretion of many glands on thirty leaves, which had not been in any
way excited, was tested with litmus paper; and the secretion of
twenty-two of these leaves did not in the least affect the colour,
whereas that of eight caused an exceedingly feeble and sometimes
doubtful tinge of red. Two other old leaves, however, which appeared to
have been inflected several times, acted much more decidedly on the
paper. Particles of clean glass were then placed on five of the leaves,
cubes of albumen on six, and bits of raw meat on three, on none of
which was the secretion at this time in the least acid. After an
interval of 24 hrs., when almost all the tentacles on

* It appears, however, according to Schiff, and contrary to the opinion
of some physiologists, that weak hydrochloric dissolves, though slowly,
a very minute quantity of coagulated albumen. Schiff, 'Phys. de la
Digestion,' tom. ii. 1867, p. 25.  [page 87]

these fourteen leaves had become more or less inflected, I again tested
the secretion, selecting glands which had not as yet reached the centre
or touched any object, and it was now plainly acid. The degree of
acidity of the secretion varied somewhat on the glands of the same
leaf. On some leaves, a few tentacles did not, from some unknown cause,
become inflected, as often happens; and in five instances their
secretion was found not to be in the least acid; whilst the secretion
of the adjoining and inflected tentacles on the same leaf was decidedly
acid. With leaves excited by particles of glass placed on the central
glands, the secretion which collects on the disc beneath them was much
more strongly acid than that poured forth from the exterior tentacles,
which were as yet only moderately inflected. When bits of albumen (and
this is naturally alkaline), or bits of meat were placed on the disc,
the secretion collected beneath them was likewise strongly acid. As raw
meat moistened with water is slightly acid, I compared its action on
litmus paper before it was placed on the leaves, and afterwards when
bathed in the secretion; and there could not be the least doubt that
the latter was very much more acid. I have indeed tried hundreds of
times the state of the secretion on the discs of leaves which were
inflected over various objects, and never failed to find it acid. We
may, therefore, conclude that the secretion from unexcited leaves,
though extremely viscid, is not acid or only slightly so, but that it
becomes acid, or much more strongly so, after the tentacles have begun
to bend over any inorganic or organic object; and still more strongly
acid after the tentacles have remained for some time closely clasped
over any object.

I may here remind the reader that the secretion [page 88] appears to be
to a certain extent antiseptic, as it checks the appearance of mould
and infusoria, thus preventing for a time the discoloration and decay
of such substances as the white of an egg, cheese, &c. It therefore
acts like the gastric juice of the higher animals, which is known to
arrest putrefaction by destroying the microzymes.

[As I was anxious to learn what acid the secretion contained, 445
leaves were washed in distilled water, given me by Prof. Frankland; but
the secretion is so viscid that it is scarcely possible to scrape or
wash off the whole. The conditions were also unfavourable, as it was
late in the year and the leaves were small. Prof. Frankland with great
kindness undertook to test the fluid thus collected. The leaves were
excited by clean particles of glass placed on them 24 hrs. previously.
No doubt much more acid would have been secreted had the leaves been
excited by animal matter, but this would have rendered the analysis
more difficult. Prof.  Frankland informs me that the fluid contained no
trace of hydrochloric, sulphuric, tartaric, oxalic, or formic acids.
This having been ascertained, the remainder of the fluid was evaporated
nearly to dryness, and acidified with sulphuric acid; it then evolved
volatile acid vapour, which was condensed and digested with carbonate
of silver. "The weight of the silver salt thus produced was only .37
gr., much too small a quantity for the accurate determination of the
molecular weight of the acid. The number obtained, however,
corresponded nearly with that of propionic acid; and I believe that
this, or a mixture of acetic and butyric acids, were present in the
liquid. The acid doubtless belongs to the acetic or fatty series."

Prof. Frankland, as well as his assistant, observed (and this is an
important fact) that the fluid, "when acidified with sulphuric acid,
emitted a powerful odour like that of pepsin." The leaves from which
the secretion had been washed were also sent to Prof. Frankland; they
were macerated for some hours, then acidified with sulphuric acid and
distilled, but no acid passed over. Therefore the acid which fresh
leaves contain, as shown by their discolouring litmus paper when
crushed, must be of a different nature from that present in the
secretion.  Nor was any odour of pepsin emitted by them.  [page 89]

Although it has long been known that pepsin with acetic acid has the
power of digesting albuminous compounds, it appeared advisable to
ascertain whether acetic acid could be replaced, without the loss of
digestive power, by the allied acids which are believed to occur in the
secretion of Drosera, namely, propionic, butyric, or valerianic. Dr.
Burdon Sanderson was so kind as to make for me the following
experiments, the results of which are valuable, independently of the
present inquiry. Prof. Frankland supplied the acids.

"1. The purpose of the following experiments was to determine the
digestive activity of liquids containing pepsin, when acidulated with
certain volatile acids belonging to the acetic series, in comparison
with liquids acidulated with hydrochloric acid, in proportion similar
to that in which it exists in gastric juice.

"2. It has been determined empirically that the best results are
obtained in artificial digestion when a liquid containing two per
thousand of hydrochloric acid gas by weight is used. This corresponds
to about 6.25 cubic centimetres per litre of ordinary strong
hydrochloric acid.  The quantities of propionic, butyric, and
valerianic acids respectively which are required to neutralise as much
base as 6.25 cubic centimetres of HCl, are in grammes 4.04 of propionic
acid, 4.82 of butyric acid, and 5.68 of valerianic acid. It was
therefore judged expedient, in comparing the digestive powers of these
acids with that of hydrochloric acid, to use them in these
proportions.

"3. Five hundred cub. cent. of a liquid containing about 8 cub. cent.
of a glycerine extract of the mucous membrane of the stomach of a dog
killed during digestion having been prepared, 10 cub. cent. of it were
evaporated and dried at 110o. This quantity yielded 0.0031 of residue.

"4. Of this liquid four quantities were taken which were severally
acidulated with hydrochloric, propionic, butyric, and valerianic acids,
in the proportions above indicated.  Each liquid was then placed in a
tube, which was allowed to float in a water bath, containing a
thermometer which indicated a temperature of 38o to 40o Cent. Into
each, a quantity of unboiled fibrin was introduced, and the whole
allowed to stand for four hours, the temperature being maintained
during the whole time, and care being taken that each contained
throughout an excess of fibrin. At the end of the period each liquid
was filtered. Of the filtrate, which of course contained as much of the
fibrin as had been digested during the four hours, [page 90] 10 cub.
cent. were measured out and evaporated, and dried at 110o as before.
The residues were respectively--

"In the liquid containing hydrochloric acid 0.4079 " " propionic acid
0.0601 " " butyric acid 0.1468 " " valerianic acid 0.1254

"Hence, deducting from each of these the above-mentioned residue, left
when the digestive liquid itself was evaporated, viz. 0.0031, we have,

"For propionic acid 0.0570 " butyric acid 0.1437 " valerianic acid
0.1223

as compared with 0.4048 for hydrochloric acid; these several numbers
expressing the quantities of fibrin by weight digested in presence of
equivalent quantities of the respective acids under identical
conditions.

"The results of the experiment may be stated thus:--If 100 represent
the digestive power of a liquid containing pepsin with the usual
proportion of hydrochloric acid, 14.0, 35.4, and 30.2, will represent
respectively the digestive powers of the three acids under
investigation.

"5. In a second experiment in which the procedure was in every respect
the same, excepting that all the tubes were plunged into the same
water-bath, and the residues dried at 115o C., the results were as
follows:--

"Quantity of fibrin dissolved in four hours by 10 cub. cent. of the
liquid:--

"Propionic acid 0.0563 Butyric acid 0.0835 Valerianic acid 0.0615

"The quantity digested by a similar liquid containing hydrochloric acid
was 0.3376. Hence, taking this as 100, the following numbers represent
the relative quantities digested by the other acids:--

"Propionic acid 16.5 Butyric acid 24.7 Valerianic acid 16.1

"6. A third experiment of the same kind gave:  [page 91]

"Quantity of fibrin digested in four hours by 10 cub. cent. of the
liquid:--

"Hydrochloric acid 0.2915 Propionic acid 0.1490 Butyric acid 0.1044
Valerianic acid 0.0520

"Comparing, as before, the three last numbers with the first taken as
100, the digestive power of propionic acid is represented by 16.8; that
of butyric acid by 35.8; and that of valerianic by 17.8.

"The mean of these three sets of observations (hydrochloric acid being
taken as 100) gives for

"Propionic acid 15.8 Butyric acid 32.0 Valerianic acid 21.4

"7. A further experiment was made to ascertain whether the digestive
activity of butyric acid (which was selected as being apparently the
most efficacious) was relatively greater at ordinary temperatures than
at the temperature of the body. It was found that whereas 10 cub.
cent. of a liquid containing the ordinary proportion of hydrochloric
acid digested 0.1311 gramme, a similar liquid prepared with butyric
acid digested 0.0455 gramme of fibrin.

"Hence, taking the quantities digested with hydrochloric acid at the
temperature of the body as 100, we have the digestive power of
hydrochloric acid at the temperature of 16o to 18oCent. represented by
44.9; that of butyric acid at the same temperature being 15.6."

We here see that at the lower of these two temperatures, hydrochloric
acid with pepsin digests, within the same time, rather less than half
the quantity of fibrin compared with what it digests at the higher
temperature; and the power of butyric acid is reduced in the same
proportion under similar conditions and temperatures. We have also seen
that butyric acid, which is much more efficacious than propionic or
valerianic acids, digests with pepsin at the higher temperature less
than a third of the fibrin which is digested at the same temperature by
hydrochloric acid.] [page 92]

I will now give in detail my experiments on the digestive power of the
secretion of Drosera, dividing the substances tried into two series,
namely those which are digested more or less completely, and those
which are not digested. We shall presently see that all these
substances are acted on by the gastric juice of the higher animals in
the same manner. I beg leave to call attention to the experiments under
the head albumen, showing that the secretion loses its power when
neutralised by an alkali, and recovers it when an acid is added.

Substances which are completely or partially digested by the Secretion
of Drosera.

Albumen.--After having tried various substances, Dr. Burdon Sanderson
suggested to me the use of cubes of coagulated albumen or hard-boiled
egg. I may premise that five cubes of the same size as those used in
the following experiments were placed for the sake of comparison at the
same time on wet moss close to the plants of Drosera. The weather was
hot, and after four days some of the cubes were discoloured and mouldy,
with their angles a little rounded; but they were not surrounded by a
zone of transparent fluid as in the case of those undergoing digestion.
Other cubes retained their angles and white colour. After eight days
all were somewhat reduced in size, discoloured, with their angles much
rounded. Nevertheless in four out of the five specimens, the central
parts were still white and opaque. So that their state differed widely,
as we shall see, from that of the cubes subjected to the action of the
secretion.

[Experiment 1.

Rather large cubes of albumen were first tried; the tentacles were well
inflected in 24 hrs.; after an [page 93] additional day the angles of
the cubes were dissolved and rounded;* but the cubes were too large, so
that the leaves were injured, and after seven days one died and the
others were dying. Albumen which has been kept for four or five days,
and which, it may be presumed, has begun to decay slightly, seems to
act more quickly than freshly boiled eggs. As the latter were generally
used, I often moistened them with a little saliva, to make the
tentacles close more quickly.

Experiment 2.--A cube of 1/10 of an inch (i.e. with each side 1/10 of
an inch, or 2.54 mm. in length) was placed on a leaf, and after 50 hrs.
it was converted into a sphere about 3/40 of an inch (1.905 mm.) in
diameter, surrounded by perfectly transparent fluid. After ten days the
leaf re-expanded, but there was still left on the disc a minute bit of
albumen now rendered transparent. More albumen had been given to this
leaf than could be dissolved or digested.

Experiment 3.--Two cubes of albumen of 1/20 of an inch (1.27 mm.) were
placed on two leaves. After 46 hrs. every atom of one was dissolved,
and most of the liquefied matter was absorbed, the fluid which remained
being in this, as in all other cases, very acid and viscid.  The other
cube was acted on at a rather slower rate.

Experiment 4.--Two cubes of albumen of the same size as the last were
placed on two leaves, and were converted in 50 hrs. into two large
drops of transparent fluid; but when these were removed from beneath
the inflected tentacles, and viewed by reflected light under the
microscope, fine streaks of white opaque matter could be seen in the
one, and traces of similar streaks in the other. The drops were
replaced on the leaves, which re-expanded after 10 days; and now
nothing was left except a very little transparent acid fluid.

Experiment 5.--This experiment was slightly varied, so that the albumen
might be more quickly exposed to the action of the secretion. Two
cubes, each of about 1/40 of an inch (.635 mm.), were placed on the
same leaf, and two similar cubes on another

* In all my numerous experiments on the digestion of cubes of albumen,
the angles and edges were invariably first rounded. Now, Schiff states
('Leons phys. de la Digestion,' vol. ii. 1867, page 149) that this is
characteristic of the digestion of albumen by the gastric juice of
animals. On the other hand, he remarks "les dissolutions, en chimie,
ont lieu sur toute la surface des corps en contact avec l'agent
dissolvant." [page 94]

leaf. These were examined after 21 hrs. 30 m., and all four were found
rounded. After 46 hrs.  the two cubes on the one leaf were completely
liquefied, the fluid being perfectly transparent; on the other leaf
some opaque white streaks could still be seen in the midst of the
fluid. After 72 hrs. these streaks disappeared, but there was still a
little viscid fluid left on the disc; whereas it was almost all
absorbed on the first leaf. Both leaves were now beginning to
re-expand.]

The best and almost sole test of the presence of some ferment analogous
to pepsin in the secretion appeared to be to neutralise the acid of the
secretion with an alkali, and to observe whether the process of
digestion ceased; and then to add a little acid and observe whether the
process recommenced. This was done, and, as we shall see, with success,
but it was necessary first to try two control experiments; namely,
whether the addition of minute drops of water of the same size as those
of the dissolved alkalies to be used would stop the process of
digestion; and, secondly, whether minute drops of weak hydrochloric
acid, of the same strength and size as those to be used, would injure
the leaves. The two following experiments were therefore tried:--

Experiment 6.--Small cubes of albumen were put on three leaves, and
minute drops of distilled water on the head of a pin were added two or
three times daily. These did not in the least delay the process; for,
after 48 hrs., the cubes were completely dissolved on all three leaves.
On the third day the leaves began to re-expand, and on the fourth day
all the fluid was absorbed.

Experiment 7.--Small cubes of albumen were put on two leaves, and
minute drops of hydrochloric acid, of the strength of one part to 437
of water, were added two or three times.  This did not in the least
delay, but seemed rather to hasten, the process of digestion; for every
trace of the albumen disappeared in 24 hrs. 30 m. After three days the
leaves partially re-expanded, and by this time almost all the viscid
fluid on their discs was absorbed. It is almost superfluous to state
that [page 95] cubes of albumen of the same size as those above used,
left for seven days in a little hydrochloric acid of the above
strength, retained all their angles as perfect as ever.

Experiment 8.--Cubes of albumen (of 1/20 of an inch, or 2.54 mm.) were
placed on five leaves, and minute drops of a solution of one part of
carbonate of soda to 437 of water were added at intervals to three of
them, and drops of carbonate of potash of the same strength to the
other two. The drops were given on the head of a rather large pin, and
I ascertained that each was equal to about 1/10 of a minim (.0059 ml.),
so that each contained only 1/4800 of a grain (.0135 mg.) of the
alkali. This was not sufficient, for after 46 hrs. all five cubes were
dissolved.

Experiment 9.--The last experiment was repeated on four leaves, with
this difference, that drops of the same solution of carbonate of soda
were added rather oftener, as often as the secretion became acid, so
that it was much more effectually neutralised. And now after 24 hrs.
the angles of three of the cubes were not in the least rounded, those
of the fourth being so in a very slight degree. Drops of extremely weak
hydrochloric acid (viz. one part to 847 of water) were then added, just
enough to neutralise the alkali which was still present; and now
digestion immediately recommenced, so that after 23 hrs. 30 m. three of
the cubes were completely dissolved, whilst the fourth was converted
into a minute sphere, surrounded by transparent fluid; and this sphere
next day disappeared.

Experiment 10.--Stronger solutions of carbonate of soda and of potash
were next used, viz.  one part to 109 of water; and as the same-sized
drops were given as before, each drop contained 1/1200 of a grain
(.0539 mg.) of either salt. Two cubes of albumen (each about 1/40 of an
inch, or .635 mm.) were placed on the same leaf, and two on another.
Each leaf received, as soon as the secretion became slightly acid (and
this occurred four times within 24 hrs.), drops either of the soda or
potash, and the acid was thus effectually neutralised. The experiment
now succeeded perfectly, for after 22 hrs. the angles of the cubes were
as sharp as they were at first, and we know from experiment 5 that such
small cubes would have been completely rounded within this time by the
secretion in its natural state. Some of the fluid was now removed with
blotting-paper from the discs of the leaves, and minute drops of
hydrochloric acid of the strength of the one part to 200 of water was
added. Acid of this greater strength was used as the solutions of the
alkalies were stronger. The [page 96] process of digestion now
commenced, so that within 48 hrs. from the time when the acid was given
the four cubes were not only completely dissolved, but much of the
liquefied albumen was absorbed.

Experiment 11.--Two cubes of albumen (1/40 of an inch, or .635 mm.)
were placed on two leaves, and were treated with alkalies as in the
last experiment, and with the same result; for after 22 hrs. they had
their angles perfectly sharp, showing that the digestive process had
been completely arrested. I then wished to ascertain what would be the
effect of using stronger hydrochloric acid; so I added minute drops of
the strength of 1 per cent. This proved rather too strong, for after 48
hrs. from the time when the acid was added one cube was still almost
perfect, and the other only very slightly rounded, and both were
stained slightly pink.  This latter fact shows that the leaves were
injured,* for during the normal process of digestion the albumen is not
thus coloured, and we can thus understand why the cubes were not
dissolved.]

From these experiments we clearly see that the secretion has the power
of dissolving albumen, and we further see that if an alkali is added,
the process of digestion is stopped, but immediately recommences as
soon as the alkali is neutralised by weak hydrochloric acid.  Even if I
had tried no other experiments than these, they would have almost
sufficed to prove that the glands of Drosera secrete some ferment
analogous to pepsin, which in presence of an acid gives to the
secretion its power of dissolving albuminous compounds.

Splinters of clean glass were scattered on a large number of leaves,
and these became moderately inflected. They were cut off and divided
into three lots; two of them, after being left for some time in a
little distilled water, were strained, and some dis-

* Sachs remarks ('Trait de Bot.' 1874, p. 774), that cells which are
killed by freezing, by too great heat, or by chemical agents, allow all
their colouring matter to escape into the surrounding water.  [page 97]

coloured, viscid, slightly acid fluid was thus obtained. The third lot
was well soaked in a few drops of glycerine, which is well known to
dissolve pepsin. Cubes of albumen (1/20 of an inch) were now placed in
the three fluids in watch-glasses, some of which were kept for several
days at about 90o Fahr. (32o.2 Cent.), and others at the temperature of
my room; but none of the cubes were dissolved, the angles remaining as
sharp as ever. This fact probably indicates that the ferment is not
secreted until the glands are excited by the absorption of a minute
quantity of already soluble animal matter,--a conclusion which is
supported by what we shall hereafter see with respect to Dionaea. Dr.
Hooker likewise found that, although the fluid within the pitchers of
Nepenthes possesses extraordinary power of digestion, yet when removed
from the pitchers before they have been excited and placed in a vessel,
it has no such power, although it is already acid; and we can account
for this fact only on the supposition that the proper ferment is not
secreted until some exciting matter is absorbed.

On three other occasions eight leaves were strongly excited with
albumen moistened with saliva; they were then cut off, and allowed to
soak for several hours or for a whole day in a few drops of glycerine.
Some of this extract was added to a little hydrochloric acid of various
strengths (generally one to 400 of water), and minute cubes of albumen
were placed in the mixture.* In two of these trials the cubes were not
in the least acted on; but in the third

* As a control experiment bits of albumen were placed in the same
glycerine with hydrochloric acid of the same strength; and the albumen,
as might have been expected, was not in the least affected after two
days.  [page 98]

the experiment was successful. For in a vessel containing two cubes,
both were reduced in size in 3 hrs.; and after 24 hrs. mere streaks of
undissolved albumen were left. In a second vessel, containing two
minute ragged bits of albumen, both were likewise reduced in size in 3
hrs., and after 24 hrs. completely disappeared. I then added a little
weak hydrochloric acid to both vessels, and placed fresh cubes of
albumen in them; but these were not acted on. This latter fact is
intelligible according to the high authority of Schiff,* who has
demonstrated, as he believes, in opposition to the view held by some
physiologists, that a certain small amount of pepsin is destroyed
during the act of digestion. So that if my solution contained, as is
probable, an extremely small amount of the ferment, this would have
been consumed by the dissolution of the cubes of albumen first given;
none being left when the hydrochloric acid was added. The destruction
of the ferment during the process of digestion, or its absorption after
the albumen had been converted into a peptone, will also account for
only one out of the three latter sets of experiments having been
successful.

Digestion of Roast Meat.--Cubes of about 1/20 of an inch (1.27 mm.) of
moderately roasted meat were placed on five leaves which became in 12
hrs. closely inflected. After 48 hrs. I gently opened one leaf, and the
meat now consisted of a minute central sphere, partially digested and
surrounded by a thick envelope of transparent viscid fluid. The whole,
without being much disturbed, was removed and placed under the
microscope. In the central part the transverse striae on the muscular
fibres were quite distinct; and it was

* 'Leons phys. de la Digestion,' 1867, tom. ii. pp. 114-126.  [page 99]

interesting to observe how gradually they disappeared, when the same
fibre was traced into the surrounding fluid. They disappeared by the
striae being replaced by transverse lines formed of excessively minute
dark points, which towards the exterior could be seen only under a very
high power; and ultimately these points were lost. When I made these
observations, I had not read Schiff's account* of the digestion of meat
by gastric juice, and I did not understand the meaning of the dark
points. But this is explained in the following statement, and we
further see how closely similar is the process of digestion by gastric
juice and by the secretion of Drosera.

["On a dit le suc gastrique faisait perdre  la fibre musculaire ses
stries transversales. Ainsi nonce, cette proposition pourrait donner
lieu  une quivoque, car ce qui se perd, ce n'est que l'aspect extrieur
de la striature et non les lments anatomiques qui la composent. On sait
que les stries qui donnent un aspect si caractristique  la fibre
musculaire, sont le rsultat de la juxtaposition et du paralllisme des
corpuscules lmentaires, placs, distances gales, dans l'intrieur des
fibrilles contigus. Or, ds que le tissu connectif qui relie entre elles
les fibrilles lmentaires vient  se gonfler et  se dissoudre, et que les
fibrilles elles-mmes se dissocient, ce paralllisme est dtruit et avec
lui l'aspect, le phnomne optique des stries. Si, aprs la dsagrgation
des fibres, on examine au microscope les fibrilles lmentaires, on
distingue encore trs-nettement  leur intrieur les corpuscules, et on
continue  les voir, de plus en plus ples, jusqu'au moment o les
fibrilles elles-mmes se liqufient et disparaissent dans le suc
gastrique. Ce qui constitue la striature,
 proprement parler, n'est donc pas dtruit, avant la liqufaction de la
 fibre charnue elle-mme."]

In the viscid fluid surrounding the central sphere of undigested meat
there were globules of fat and little bits of fibro-elastic tissue;
neither of which were in

* 'Leons phys. de la Digestion,' tom. ii. p. 145.  [page 100]

the least digested. There were also little free parallelograms of
yellowish, highly translucent matter. Schiff, in speaking of the
digestion of meat by gastric juice, alludes to such parallelograms, and
says:--

["Le gonflement par lequel commence la digestion de la viande, rsulte
de l'action du suc gastrique acide sur le tissu connectif qui se
dissout d'abord, et qui, par sa liqufaction, dsagrge les fibrilles.
Celles-ci se dissolvent ensuite en grande partie, mais, avant de passer
 l'tat liquide, elles tendent  se briser en petits fragments
 transversaux. Les 'sarcous elements' de Bowman, qui ne sont autre
chose que les produits de cette division transversale des fibrilles
lmentaires, peuvent tre prpars et isols  l'aide du suc gastrique,
pourvu qu'on n'attend pas jusqu' la liqufaction complte du muscle."]

After an interval of 72 hrs., from the time when the five cubes were
placed on the leaves, I opened the four remaining ones. On two nothing
could be seen but little masses of transparent viscid fluid; but when
these were examined under a high power, fat-globules, bits of
fibro-elastic tissue, and some few parallelograms of sarcous matter,
could be distinguished, but not a vestige of transverse striae. On the
other two leaves there were minute spheres of only partially digested
meat in the centre of much transparent fluid.

Fibrin.--Bits of fibrin were left in water during four days, whilst the
following experiments were tried, but they were not in the least acted
on. The fibrin which I first used was not pure, and included dark
particles: it had either not been well prepared or had subsequently
undergone some change. Thin portions, about 1/10 of an inch square,
were placed on several leaves, and though the fibrin was soon
liquefied, the whole was never dissolved. Smaller particles were then
placed on four leaves, and minute [page 101] drops of hydrochloric acid
(one part to 437 of water) were added; this seemed to hasten the
process of digestion, for on one leaf all was liquified and absorbed
after 20 hrs.; but on the three other leaves some undissolved residue
was left after 48 hrs. It is remarkable that in all the above and
following experiments, as well as when much larger bits of fibrin were
used, the leaves were very little excited; and it was sometimes
necessary to add a little saliva to induce complete inflection. The
leaves, moreover, began to re-expand after only 48 hrs., whereas they
would have remained inflected for a much longer time had insects, meat,
cartilage, albumen, &c., been placed on them.

I then tried some pure white fibrin, sent me by Dr. Burdon Sanderson.

[Experiment 1.--Two particles, barely 1/20 of an inch (1.27 mm.)
square, were placed on opposite sides of the same leaf. One of these
did not excite the surrounding tentacles, and the gland on which it
rested soon dried. The other particle caused a few of the short
adjoining tentacles to be inflected, the more distant ones not being
affected. After 24 hrs. both were almost, and after 72 hrs. completely,
dissolved.

Experiment 2.--The same experiment with the same result, only one of
the two bits of fibrin exciting the short surrounding tentacles. This
bit was so slowly acted on that after a day I pushed it on to some
fresh glands. In three days from the time when it was first placed on
the leaf it was completely dissolved.

Experiment 3.--Bits of fibrin of about the same size as before were
placed on the discs of two leaves; these caused very little inflection
in 23 hrs., but after 48 hrs. both were well clasped by the surrounding
short tentacles, and after an additional 24 hrs. were completely
dissolved.  On the disc of one of these leaves much clear acid fluid
was left.

Experiment 4.--Similar bits of fibrin were placed on the discs of two
leaves; as after 2 hrs.  the glands seemed rather dry, they were freely
moistened with saliva; this soon caused strong inflection both of the
tentacles and blades, with copious [page 102] secretion from the
glands. In 18 hrs. the fibrin was completely liquefied, but undigested
atoms still floated in the liquid; these, however, disappeared in under
two additional days.]

From these experiments it is clear that the secretion completely
dissolves pure fibrin. The rate of dissolution is rather slow; but this
depends merely on this substance not exciting the leaves sufficiently,
so that only the immediately adjoining tentacles are inflected, and the
supply of secretion is small.

Syntonin.--This substance, extracted from muscle, was kindly prepared
for me by Dr. Moore.  Very differently from fibrin, it acts quickly and
energetically. Small portions placed on the discs of three leaves
caused their tentacles and blades to be strongly inflected within 8
hrs.; but no further observations were made. It is probably due to the
presence of this substance that raw meat is too powerful a stimulant,
often injuring or even killing the leaves.

Areolar Tissue.--Small portions of this tissue from a sheep were placed
on the discs of three leaves; these became moderately well inflected in
24 hrs., but began to re-expand after 48 hrs., and were fully
re-expanded in 72 hrs., always reckoning from the time when the bits
were first given. This substance, therefore, like fibrin, excites the
leaves for only a short time.  The residue left on the leaves, after
they were fully re-expanded, was examined under a high power and found
much altered, but, owing to the presence of a quantity of elastic
tissue, which is never acted on, could hardly be said to be in a
liquefied condition.

Some areolar tissue free from elastic tissue was next procured from the
visceral cavity of a toad, and moderately sized, as well as very small,
bits were placed on five leaves. After 24 hrs. two of the bits [page
103] were completely liquefied; two others were rendered transparent,
but not quite liquefied; whilst the fifth was but little affected.
Several glands on the three latter leaves were now moistened with a
little saliva, which soon caused much inflection and secretion, with
the result that in the course of 12 additional hrs. one leaf alone
showed a remnant of undigested tissue. On the discs of the four other
leaves (to one of which a rather large bit had been given) nothing was
left except some transparent viscid fluid. I may add that some of this
tissue included points of black pigment, and these were not at all
affected. As a control experiment, small portions of this tissue were
left in water and on wet moss for the same length of time, and remained
white and opaque. From these facts it is clear that areolar tissue is
easily and quickly digested by the secretion; but that it does not
greatly excite the leaves.

Cartilage.--Three cubes (1/20 of an inch or 1.27 mm.) of white,
translucent, extremely tough cartilage were cut from the end of a
slightly roasted leg-bone of a sheep. These were placed on three
leaves, borne by poor, small plants in my greenhouse during November;
and it seemed in the highest degree improbable that so hard a substance
would be digested under such unfavourable circumstances. Nevertheless,
after 48 hrs., the cubes were largely dissolved and converted into
minute spheres, surrounded by transparent, very acid fluid. Two of
these spheres were completely softened to their centres; whilst the
third still contained a very small irregularly shaped core of solid
cartilage. Their surfaces were seen under the microscope to be
curiously marked by prominent ridges, showing that the cartilage had
been unequally corroded by the secretion. I need hardly [page 104] say
that cubes of the same cartilage, kept in water for the same length of
time, were not in the least affected.

During a more favourable season, moderately sized bits of the skinned
ear of a cat, which includes cartilage, areolar and elastic tissue,
were placed on three leaves. Some of the glands were touched with
saliva, which caused prompt inflection. Two of the leaves began to
re-expand after three days, and the third on the fifth day. The fluid
residue left on their discs was now examined, and consisted in one case
of perfectly transparent, viscid matter; in the other two cases, it
contained some elastic tissue and apparently remnants of half digested
areolar tissue.

Fibro-cartilage  (from between the vertebrae of the tail of a sheep).
Moderately sized and small bits (the latter about 1/20 of an inch) were
placed on nine leaves. Some of these were well and some very little
inflected. In the latter case the bits were dragged over the discs, so
that they were well bedaubed with the secretion, and many glands thus
irritated. All the leaves re-expanded after only two days; so that they
were but little excited by this substance.  The bits were not
liquefied, but were certainly in an altered condition, being swollen,
much more transparent, and so tender as to disintegrate very easily. My
son Francis prepared some artificial gastric juice, which was proved
efficient by quickly dissolving fibrin, and suspended portions of the
fibro-cartilage in it. These swelled and became hyaline, exactly like
those exposed to the secretion of Drosera, but were not dissolved. This
result surprised me much, as two physiologists were of opinion that
fibro-cartilage would be easily digested by gastric juice. I therefore
asked Dr. Klein to examine the specimens; and [page 105] he reports
that the two which had been subjected to artificial gastric juice were
"in that state of digestion in which we find connective tissue when
treated with an acid, viz. swollen, more or less hyaline, the fibrillar
bundles having become homogeneous and lost their fibrillar structure."
In the specimens which had been left on the leaves of Drosera, until
they re-expanded, "parts were altered, though only slightly so, in the
same manner as those subjected to the gastric juice as they had become
more transparent, almost hyaline, with the fibrillation of the bundles
indistinct." Fibro-cartilage is therefore acted on in nearly the same
manner by gastric juice and by the secretion of Drosera.

Bone.--Small smooth bits of the dried hyoidal bone of a fowl moistened
with saliva were placed on two leaves, and a similarly moistened
splinter of an extremely hard, broiled mutton-chop bone on a third
leaf. These leaves soon became strongly inflected, and remained so for
an unusual length of time; namely, one leaf for ten and the other two
for nine days.  The bits of bone were surrounded all the time by acid
secretion. When examined under a weak power, they were found quite
softened, so that they were readily penetrated by a blunt needle, torn
into fibres, or compressed. Dr. Klein was so kind as to make sections
of both bones and examine them. He informs me that both presented the
normal appearance of decalcified bone, with traces of the earthy salts
occasionally left. The corpuscles with their processes were very
distinct in most parts; but in some parts, especially near the
periphery of the hyoidal bone, none could be seen. Other parts again
appeared amorphous, with even the longitudinal striation of bone not
distinguishable. This amorphous structure, [page 106] as Dr. Klein
thinks, may be the result either of the incipient digestion of the
fibrous basis or of all the animal matter having been removed, the
corpuscles being thus rendered invisible. A hard, brittle, yellowish
substance occupied the position of the medulla in the fragments of the
hyoidal bone.

As the angles and little projections of the fibrous basis were not in
the least rounded or corroded, two of the bits were placed on fresh
leaves. These by the next morning were closely inflected, and remained
so,--the one for six and the other for seven days,--therefore for not
so long a time as on the first occasion, but for a much longer time
than ever occurs with leaves inflected over inorganic or even over many
organic bodies. The secretion during the whole time coloured litmus
paper of a bright red; but this may have been due to the presence of
the acid super-phosphate of lime. When the leaves re-expanded, the
angles and projections of the fibrous basis were as sharp as ever. I
therefore concluded, falsely as we shall presently see, that the
secretion cannot touch the fibrous basis of bone. The more probable
explanation is that the acid was all consumed in decomposing the
phosphate of lime which still remained; so that none was left in a free
state to act in conjunction with the ferment on the fibrous basis.

Enamel and Dentine.--As the secretion decalcified ordinary bone, I
determined to try whether it would act on enamel and dentine, but did
not expect that it would succeed with so hard a substance as enamel.
Dr. Klein gave me some thin transverse slices of the canine tooth of a
dog; small angular fragments of which were placed on four leaves; and
these were examined each succeeding day at the same hour. The results
are, I think, worth giving in detail.] [page 107]

[Experiment 1.--May 1st, fragment placed on leaf; 3rd, tentacles but
little inflected, so a little saliva was added; 6th, as the tentacles
were not strongly inflected, the fragment was transferred to another
leaf, which acted at first slowly, but by the 9th closely embraced it.
On the 11th this second leaf began to re-expand; the fragment was
manifestly softened, and Dr.  Klein reports, "a great deal of enamel
and the greater part of the dentine decalcified."

Experiment 2.--May 1st, fragment placed on leaf; 2nd, tentacles fairly
well inflected, with much secretion on the disc, and remained so until
the 7th, when the leaf re-expanded. The fragment was now transferred to
a fresh leaf, which next day (8th) was inflected in the strongest
manner, and thus remained until the 11th, when it re-expanded. Dr.
Klein reports, "a great deal of enamel and the greater part of the
dentine decalcified."

Experiment 3.--May 1st, fragment moistened with saliva and placed on a
leaf, which remained well inflected until 5th, when it re-expanded. The
enamel was not at all, and the dentine only slightly, softened. The
fragment was now transferred to a fresh leaf, which next morning (6th)
was strongly inflected, and remained so until the 11th. The enamel and
dentine both now somewhat softened; and Dr. Klein reports, "less than
half the enamel, but the greater part of the dentine decalcified."

Experiment 4.--May 1st, a minute and thin bit of dentine, moistened
with saliva, was placed on a leaf, which was soon inflected, and
re-expanded on the 5th. The dentine had become as flexible as thin
paper. It was then transferred to a fresh leaf, which next morning
(6th) was strongly inflected, and reopened on the 10th. The decalcified
dentine was now so tender that it was torn into shreds merely by the
force of the re-expanding tentacles.]

From these experiments it appears that enamel is attacked by the
secretion with more difficulty than dentine, as might have been
expected from its extreme hardness; and both with more difficulty than
ordinary bone. After the process of dissolution has once commenced, it
is carried on with greater ease; this may be inferred from the leaves,
to which the fragments were transferred, becoming in all four cases
strongly inflected in the course of a single day; whereas the first set
of leaves acted much less quickly and [page 108] energetically. The
angles or projections of the fibrous basis of the enamel and dentine
(except, perhaps, in No. 4, which could not be well observed) were not
in the least rounded; and Dr. Klein remarks that their microscopical
structure was not altered. But this could not have been expected, as
the decalcification was not complete in the three specimens which were
carefully examined.

Fibrous Basis of Bone.--I at first concluded, as already stated, that
the secretion could not digest this substance. I therefore asked Dr.
Burdon Sanderson to try bone, enamel, and dentine, in artificial
gastric juice, and he found that they were after a considerable time
completely dissolved. Dr. Klein examined some of the small lamellae,
into which part of the skull of a cat became broken up after about a
week's immersion in the fluid, and he found that towards the edges the
"matrix appeared rarefied, thus producing the appearance as if the
canaliculi of the bone-corpuscles had become larger. Otherwise the
corpuscles and their canaliculi were very distinct." So that with bone
subjected to artificial gastric juice complete decalcification precedes
the dissolution of the fibrous basis. Dr. Burdon Sanderson suggested to
me that the failure of Drosera to digest the fibrous basis of bone,
enamel, and dentine, might be due to the acid being consumed in the
decomposition of the earthy salts, so that there was none left for the
work of digestion. Accordingly, my son thoroughly decalcified the bone
of a sheep with weak hydrochloric acid; and seven minute fragments of
the fibrous basis were placed on so many leaves, four of the fragments
being first damped with saliva to aid prompt inflection. All seven
leaves became inflected, but only very moderately, in the course of a
day.  [page 109] They quickly began to re-expand; five of them on the
second day, and the other two on the third day. On all seven leaves the
fibrous tissue was converted into perfectly transparent, viscid, more
or less liquefied little masses. In the middle, however, of one, my son
saw under a high power a few corpuscles, with traces of fibrillation in
the surrounding transparent matter. From these facts it is clear that
the leaves are very little excited by the fibrous basis of bone, but
that the secretion easily and quickly liquefies it, if thoroughly
decalcified. The glands which had remained in contact for two or three
days with the viscid masses were not discoloured, and apparently had
absorbed little of the liquefied tissue, or had been little affected by
it.

Phosphate of Lime.--As we have seen that the tentacles of the first set
of leaves remained clasped for nine or ten days over minute fragments
of bone, and the tentacles of the second set for six or seven days over
the same fragments, I was led to suppose that it was the phosphate of
lime, and not any included animal matter, which caused such long
continued inflection. It is at least certain from what has just been
shown that this cannot have been due to the presence of the fibrous
basis. With enamel and dentine (the former of which contains only 4 per
cent. of organic matter) the tentacles of two successive sets of leaves
remained inflected altogether for eleven days. In order to test my
belief in the potency of phosphate of lime, I procured some from Prof.
Frankland absolutely free of animal matter and of any acid.  A small
quantity moistened with water was placed on the discs of two leaves.
One of these was only slightly affected; the other remained closely
inflected for ten days, when a few of the tentacles began to [page 110]
re-expand, the rest being much injured or killed. I repeated the
experiment, but moistened the phosphate with saliva to insure prompt
inflection; one leaf remained inflected for six days (the little saliva
used would not have acted for nearly so long a time) and then died; the
other leaf tried to re-expand on the sixth day, but after nine days
failed to do so, and likewise died.  Although the quantity of phosphate
given to the above four leaves was extremely small, much was left in
every case undissolved. A larger quantity wetted with water was next
placed on the discs of three leaves; and these became most strongly
inflected in the course of 24 hrs.  They never re-expanded; on the
fourth day they looked sickly, and on the sixth were almost dead. Large
drops of not very viscid fluid hung from their edges during the six
days. This fluid was tested each day with litmus paper, but never
coloured it; and this circumstance I do not understand, as the
superphosphate of lime is acid. I suppose that some superphosphate must
have been formed by the acid of the secretion acting on the phosphate,
but that it was all absorbed and injured the leaves; the large drops
which hung from their edges being an abnormal and dropsical secretion.
Anyhow, it is manifest that the phosphate of lime is a most powerful
stimulant. Even small doses are more or less poisonous, probably on the
same principle that raw meat and other nutritious substances, given in
excess, kill the leaves.  Hence the conclusion, that the long continued
inflection of the tentacles over fragments of bone, enamel, and
dentine, is caused by the presence of phosphate of lime, and not of any
included animal matter, is no doubt correct.

Gelatine.--I used pure gelatine in thin sheets given [page 111] me by
Prof. Hoffmann. For comparison, squares of the same size as those
placed on the leaves were left close by on wet moss. These soon
swelled, but retained their angles for three days; after five days they
formed rounded, softened masses, but even on the eighth day a trace of
gelatine could still be detected. Other squares were immersed in water,
and these, though much swollen, retained their angles for six days.
Squares of 1/10 of an inch (2.54 mm.), just moistened with water, were
placed on two leaves; and after two or three days nothing was left on
them but some acid viscid fluid, which in this and other cases never
showed any tendency to regelatinise; so that the secretion must act on
the gelatine differently to what water does, and apparently in the same
manner as gastric juice.* Four squares of the same size as before were
then soaked for three days in water, and placed on large leaves; the
gelatine was liquefied and rendered acid in two days, but did not
excite much inflection. The leaves began to re-expand after four or
five days, much viscid fluid being left on their discs, as if but
little had been absorbed. One of these leaves, as soon as it
re-expanded, caught a small fly, and after 24 hrs. was closely
inflected, showing how much more potent than gelatine is the animal
matter absorbed from an insect. Some larger pieces of gelatine, soaked
for five days in water, were next placed on three leaves, but these did
not become much inflected until the third day; nor was the gelatine
completely liquefied until the fourth day.  On this day one leaf began
to re-expand; the second on the fifth; and third on the sixth. These
several facts

* Dr. Lauder Brunton, 'Handbook for the Phys. Laboratory,' 1873, pp.
477, 487; Schiff, 'Leons phys. de la Digestion,' 1867, p. 249.  [page
112]

prove that gelatine is far from acting energetically on Drosera.

In the last chapter it was shown that a solution of isinglass of
commerce, as thick as milk or cream, induces strong inflection. I
therefore wished to compare its action with that of pure gelatine.
Solutions of one part of both substances to 218 of water were made; and
half-minim drops (.0296 ml.) were placed on the discs of eight leaves,
so that each received 1/480 of a grain, or .135 mg. The four with the
isinglass were much more strongly inflected than the other four. I
conclude therefore that isinglass contains some, though perhaps very
little, soluble albuminous matter. As soon as these eight leaves
re-expanded, they were given bits of roast meat, and in some hours all
became greatly inflected; again showing how much more meat excites
Drosera than does gelatine or isinglass. This is an interesting fact,
as it is well known that gelatine by itself has little power of
nourishing animals.*

Chondrin.--This was sent me by Dr. Moore in a gelatinous state. Some
was slowly dried, and a small chip was placed on a leaf, and a much
larger chip on a second leaf. The first was liquefied in a day; the
larger piece was much swollen and softened, but was not completely
liquefied until the third day. The undried jelly was next tried, and as
a control experiment small cubes were left in water for four days and
retained their angles. Cubes of the same size were placed on two
leaves, and larger cubes on two other leaves. The tentacles and laminae
of the latter were closely inflected after 22 hrs., but those of the

* Dr. Lauder Brunton gives in the 'Medical Record,' January 1873, p.
36, an account of Voit's view of the indirect part which gelatine plays
in nutrition.  [page 113]

two leaves with the smaller cubes only to a moderate degree. The jelly
on all four was by this time liquefied, and rendered very acid. The
glands were blackened from the aggregation of their protoplasmic
contents. In 46 hrs. from the time when the jelly was given, the leaves
had almost re-expanded, and completely so after 70 hrs.; and now only a
little slightly adhesive fluid was left unabsorbed on their discs.

One part of chondrin jelly was dissolved in 218 parts of boiling water,
and half-minim drops were given to four leaves; so that each received
about 1/480 of a grain (.135 mg.) of the jelly; and, of course, much
less of dry chondrin. This acted most powerfully, for after only 3 hrs.
30 m. all four leaves were strongly inflected. Three of them began to
re-expand after 24 hrs., and in 48 hrs. were completely open; but the
fourth had only partially re-expanded. All the liquefied chondrin was
by this time absorbed. Hence a solution of chondrin seems to act far
more quickly and energetically than pure gelatine or isinglass; but I
am assured by good authorities that it is most difficult, or
impossible, to know whether chondrin is pure, and if it contained any
albuminous compound, this would have produced the above effects.
Nevertheless, I have thought these facts worth giving, as there is so
much doubt on the nutritious value of gelatine; and Dr. Lauder Brunton
does not know of any experiments with respect to animals on the
relative value of gelatine and chondrin.

Milk.--We have seen in the last chapter that milk acts most powerfully
on the leaves; but whether this is due to the contained casein or
albumen, I know not. Rather large drops of milk excite so much
secretion (which is very acid) that it sometimes trickles down [page
114] from the leaves, and this is likewise characteristic of chemically
prepared casein. Minute drops of milk, placed on leaves, were
coagulated in about ten minutes. Schiff denies* that the coagulation of
milk by gastric juice is exclusively due to the acid which is present,
but attributes it in part to the pepsin; and it seems doubtful whether
with Drosera the coagulation can be wholly due to the acid, as the
secretion does not commonly colour litmus paper until the tentacles
have become well inflected; whereas the coagulation commences, as we
have seen, in about ten minutes. Minute drops of skimmed milk were
placed on the discs of five leaves; and a large proportion of the
coagulated matter or curd was dissolved in 6 hrs. and still more
completely in 8 hrs. These leaves re-expanded after two days, and the
viscid fluid left on their discs was then carefully scraped off and
examined. It seemed at first sight as if all the casein had not been
dissolved, for a little matter was left which appeared of a whitish
colour by reflected light. But this matter, when examined under a high
power, and when compared with a minute drop of skimmed milk coagulated
by acetic acid, was seen to consist exclusively of oil-globules, more
or less aggregated together, with no trace of casein. As I was not
familiar with the microscopical appearance of milk, I asked Dr. Lauder
Brunton to examine the slides, and he tested the globules with ether,
and found that they were dissolved.  We may, therefore, conclude that
the secretion quickly dissolves casein, in the state in which it exists
in milk.

Chemically Prepared Casein.--This substance, which

* 'Leons,' &c. tom. ii. page 151.  [page 115]

is insoluble in water, is supposed by many chemists to differ from the
casein of fresh milk. I procured some, consisting of hard globules,
from Messrs. Hopkins and Williams, and tried many experiments with it.
Small particles and the powder, both in a dry state and moistened with
water, caused the leaves on which they were placed to be inflected very
slowly, generally not until two days had elapsed. Other particles,
wetted with weak hydrochloric acid (one part to 437 of water) acted in
a single day, as did some casein freshly prepared for me by Dr. Moore.
The tentacles commonly remained inflected for from seven to nine days;
and during the whole of this time the secretion was strongly acid. Even
on the eleventh day some secretion left on the disc of a fully
re-expanded leaf was strongly acid. The acid seems to be secreted
quickly, for in one case the secretion from the discal glands, on which
a little powdered casein had been strewed, coloured litmus paper,
before any of the exterior tentacles were inflected.

Small cubes of hard casein, moistened with water, were placed on two
leaves; after three days one cube had its angles a little rounded, and
after seven days both consisted of rounded softened masses, in the
midst of much viscid and acid secretion; but it must not be inferred
from this fact that the angles were dissolved, for cubes immersed in
water were similarly acted on. After nine days these leaves began to
re-expand, but in this and other cases the casein did not appear, as
far as could be judged by the eye, much, if at all, reduced in bulk.
According to Hoppe-Seyler and Lubavin* casein consists of an
albuminous, with

* Dr. Lauder Brunton, 'Handbook for Phys. Lab.' p. 529.  [page 116]

a non-albuminous, substance; and the absorption of a very small
quantity of the former would excite the leaves, and yet not decrease
the casein to a perceptible degree. Schiff asserts*--and this is an
important fact for us--that "la casine purifie des chemistes est un
corps presque compltement inattaquable par le suc gastrique." So that
here we have another point of accordance between the secretion of
Drosera and gastric juice, as both act so differently on the fresh
casein of milk, and on that prepared by chemists.

A few trials were made with cheese; cubes of 1/20 of an inch (1.27 mm.)
were placed on four leaves, and these after one or two days became well
inflected, their glands pouring forth much acid secretion. After five
days they began to re-expand, but one died, and some of the glands on
the other leaves were injured. Judging by the eye, the softened and
subsided masses of cheese, left on the discs, were very little or not
at all reduced in bulk. We may, however, infer from the time during
which the tentacles remained inflected,--from the changed colour of
some of the glands,--and from the injury done to others, that matter
had been absorbed from the cheese.

Legumin.--I did not procure this substance in a separate state; but
there can hardly be a doubt that it would be easily digested, judging
from the powerful effect produced by drops of a decoction of green
peas, as described in the last chapter. Thin slices of a dried pea,
after being soaked in water, were placed on two leaves; these became
somewhat inflected in the course of a single hour, and most strongly so
in 21 hrs. They re-expanded after three or four days.

* 'Leons' &c. tom. ii. page 153.  [page 117]

The slices were not liquefied, for the walls of the cells, composed of
cellulose, are not in the least acted on by the secretion.

Pollen.--A little fresh pollen from the common pea was placed on the
discs of five leaves, which soon became closely inflected, and remained
so for two or three days.

The grains being then removed, and examined under the microscope, were
found discoloured, with the oil-globules remarkably aggregated. Many
had their contents much shrunk, and some were almost empty. In only a
few cases were the pollen-tubes emitted.  There could be no doubt that
the secretion had penetrated the outer coats of the grains, and had
partially digested their contents. So it must be with the gastric juice
of the insects which feed on pollen, without masticating it.* Drosera
in a state of nature cannot fail to profit to a certain extent by this
power of digesting pollen, as innumerable grains from the carices,
grasses, rumices, fir-trees, and other wind-fertilised plants, which
commonly grow in the same neighbourhood, will be inevitably caught by
the viscid secretion surrounding the many glands.

Gluten.--This substance is composed of two albuminoids, one soluble,
the other insoluble in alcohol.  Some was prepared by merely washing
wheaten flour in water. A provisional trial was made with rather large
pieces placed on two leaves; these, after 21 hrs., were closely
inflected, and remained so for four days, when one was killed and the
other had its glands extremely blackened, but was not afterwards
observed.

* Mr. A.W. Bennett found the undigested coats of the grains in the
intestinal canal of pollen-eating Diptera; see 'Journal of Hort. Soc.
of London,' vol. iv. 1874, p. 158.

  Watts' 'Dict. of Chemistry,' vol. ii. 1872, p. 873.  [page 118]

Smaller bits were placed on two leaves; these were only slightly
inflected in two days, but afterwards became much more so. Their
secretion was not so strongly acid as that of leaves excited by casein.
The bits of gluten, after lying for three days on the leaves, were more
transparent than other bits left for the same time in water. After
seven days both leaves re-expanded, but the gluten seemed hardly at all
reduced in bulk. The glands which had been in contact with it were
extremely black. Still smaller bits of half putrid gluten were now
tried on two leaves; these were well inflected in 24 hrs., and
thoroughly in four days, the glands in contact being much blackened.
After five days one leaf began to re-expand, and after eight days both
were fully re-expanded, some gluten being still left on their discs.
Four little chips of dried gluten, just dipped in water, were next
tried, and these acted rather differently from fresh gluten. One leaf
was almost fully re-expanded in three days, and the other three leaves
in four days. The chips were greatly softened, almost liquefied, but
not nearly all dissolved.  The glands which had been in contact with
them, instead of being much blackened, were of a very pale colour, and
many of them were evidently killed.

In not one of these ten cases was the whole of the gluten dissolved,
even when very small bits were given. I therefore asked Dr. Burdon
Sanderson to try gluten in artificial digestive fluid of pepsin with
hydrochloric acid; and this dissolved the whole. The gluten, however,
was acted on much more slowly than fibrin; the proportion dissolved
within four hours being as 40.8 of gluten to 100 of fibrin. Gluten was
also tried in two other digestive fluids, in which hydrochloric acid
was replaced by propionic [page 119] and butyric acids, and it was
completely dissolved by these fluids at the ordinary temperature of a
room. Here, then, at last, we have a case in which it appears that
there exists an essential difference in digestive power between the
secretion of Drosera and gastric juice; the difference being confined
to the ferment, for, as we have just seen, pepsin in combination with
acids of the acetic series acts perfectly on gluten. I believe that the
explanation lies simply in the fact that gluten is too powerful a
stimulant (like raw meat, or phosphate of lime, or even too large a
piece of albumen), and that it injures or kills the glands before they
have had time to pour forth a sufficient supply of the proper
secretion. That some matter is absorbed from the gluten, we have clear
evidence in the length of time during which the tentacles remain
inflected, and in the greatly changed colour of the glands.

At the suggestion of Dr. Sanderson, some gluten was left for 15 hrs. in
weak hydrochloric acid (.02 per cent.), in order to remove the starch.
It became colourless, more transparent, and swollen. Small portions
were washed and placed on five leaves, which were soon closely
inflected, but to my surprise re-expanded completely in 48 hrs. A mere
vestige of gluten was left on two of the leaves, and not a vestige on
the other three. The viscid and acid secretion, which remained on the
discs of the three latter leaves, was scraped off and examined by my
son under a high power; but nothing could be seen except a little dirt,
and a good many starch grains which had not been dissolved by the
hydrochloric acid. Some of the glands were rather pale. We thus learn
that gluten, treated with weak hydrochloric acid, is not so powerful or
so enduring a [page 120] stimulant as fresh gluten, and does not much
injure the glands; and we further learn that it can be digested quickly
and completely by the secretion.

[Globulin or Crystallin.--This substance was kindly prepared for me
from the lens of the eye by Dr. Moore, and consisted of hard,
colourless, transparent fragments. It is said* that globulin ought to
"swell up in water and dissolve, for the most part forming a gummy
liquid;" but this did not occur with the above fragments, though kept
in water for four days. Particles, some moistened with water, others
with weak hydrochloric acid, others soaked in water for one or two
days, were placed on nineteen leaves. Most of these leaves, especially
those with the long soaked particles, became strongly inflected in a
few hours. The greater number re-expanded after three or four days; but
three of the leaves remained inflected during one, two, or three
additional days. Hence some exciting matter must have been absorbed;
but the fragments, though perhaps softened in a greater degree than
those kept for the same time in water, retained all their angles as
sharp as ever. As globulin is an albuminous substance, I was astonished
at this result; and my object being to compare the action of the
secretion with that of gastric juice, I asked Dr. Burdon Sanderson to
try some of the globulin used by me.  He reports that "it was subjected
to a liquid containing 0.2 per cent. of hydrochloric acid, and about 1
per cent. of glycerine extract of the stomach of a dog. It was then
ascertained that this liquid was capable of digesting 1.31 of its
weight of unboiled fibrin in 1 hr.; whereas, during the hour, only
0.141 of the above globulin was dissolved. In both cases an excess of
the substance to be digested was subjected to the liquid."  We thus see
that within the same time less than one-ninth by weight of globulin
than of fibrin was dissolved; and bearing in mind that pepsin with
acids of the acetic series has only about one-third of the digestive
power of pepsin with hydrochloric acid, it is not surprising that the
fragments of

* Watts' 'Dictionary of Chemistry,' vol. ii. page 874.

  I may add that Dr. Sanderson prepared some fresh globulin by
  Schmidt's method, and of this 0.865 was dissolved within the same
time, namely, one hour; so that it was far more soluble than that which
I used, though less soluble than fibrin, of which, as we have seen,
1.31 was dissolved. I wish that I had tried on Drosera globulin
prepared by this method.  [page 121]

globulin were not corroded or rounded by the secretion of Drosera,
though some soluble matter was certainly extracted from them and
absorbed by the glands.

Haematin.--Some dark red granules, prepared from bullock's blood, were
given me; these were found by Dr. Sanderson to be insoluble in water,
acids, and alcohol, so that they were probably haematin, together with
other bodies derived from the blood. Particles with little drops of
water were placed on four leaves, three of which were pretty closely
inflected in two days; the fourth only moderately so. On the third day
the glands in contact with the haematin were blackened, and some of the
tentacles seemed injured. After five days two leaves died, and the
third was dying; the fourth was beginning to re-expand, but many of its
glands were blackened and injured. It is therefore clear that matter
had been absorbed which was either actually poisonous or of too
stimulating a nature. The particles were much more softened than those
kept for the same time in water, but, judging by the eye, very little
reduced in bulk. Dr. Sanderson tried this substance with artificial
digestive fluid, in the manner described under globulin, and found that
whilst 1.31 of fibrin, only 0.456 of the haematin was dissolved in an
hour; but the dissolution by the secretion of even a less amount would
account for its action on Drosera. The residue left by the artificial
digestive fluid at first yielded nothing more to it during several
succeeding days.]

      Substances which are not Digested by the Secretion.

All the substances hitherto mentioned cause prolonged inflection of the
tentacles, and are either completely or at least partially dissolved by
the secretion. But there are many other substances, some of them
containing nitrogen, which are not in the least acted on by the
secretion, and do not induce inflection for a longer time than do
inorganic and insoluble objects. These unexciting and indigestible
substances are, as far as I have observed, epidermic productions (such
as bits of human nails, balls of hair, the quills of feathers),
fibro-elastic tissue, mucin, pepsin, urea, chitine, chlorophyll,
cellulose, gun-cotton, fat, oil, and starch.  [page 122]

To these may be added dissolved sugar and gum, diluted alcohol, and
vegetable infusions not containing albumen, for none of these, as shown
in the last chapter, excite inflection. Now, it is a remarkable fact,
which affords additional and important evidence, that the ferment of
Drosera is closely similar to or identical with pepsin, that none of
these same substances are, as far as it is known, digested by the
gastric juice of animals, though some of them are acted on by the other
secretions of the alimentary canal. Nothing more need be said about
some of the above enumerated substances, excepting that they were
repeatedly tried on the leaves of Drosera, and were not in the least
affected by the secretion. About the others it will be advisable to
give my experiments.

[Fibro-elastic Tissue.--We have already seen that when little cubes of
meat, &c., were placed on leaves, the muscles, areolar tissue, and
cartilage were completely dissolved, but the fibro-elastic tissue, even
the most delicate threads, were left without the least signs of having
been attacked. And it is well known that this tissue cannot be digested
by the gastric juice of animals.*

Mucin.--As this substance contains about 7 per cent. of nitrogen, I
expected that it would have excited the leaves greatly and been
digested by the secretion, but in this I was mistaken.  From what is
stated in chemical works, it appears extremely doubtful whether mucin
can be prepared as a pure principle. That which I used (prepared by Dr.
Moore) was dry and hard.  Particles moistened with water were placed on
four leaves, but after two days there was only a trace of inflection in
the immediately adjoining tentacles. These leaves were then tried with
bits of meat, and all four soon became strongly inflected. Some of the
dried mucin was then soaked in water for two days, and little cubes of
the proper size were placed on three leaves.  After four days the
tentacles

* See, for instance, Schiff, 'Phys. de la Digestion,' 1867, tom. ii.,
p. 38.  [page 123]

round the margins of the discs were a little inflected, and the
secretion collected on the disc was acid, but the exterior tentacles
were not affected. One leaf began to re-expand on the fourth day, and
all were fully re-expanded on the sixth. The glands which had been in
contact with the mucin were a little darkened. We may therefore
conclude that a small amount of some impurity of a moderately exciting
nature had been absorbed. That the mucin employed by me did contain
some soluble matter was proved by Dr. Sanderson, who on subjecting it
to artificial gastric juice found that in 1 hr. some was dissolved, but
only in the proportion of 23 to 100 of fibrin during the same time. The
cubes, though perhaps rather softer than those left in water for the
same time, retained their angles as sharp as ever. We may therefore
infer that the mucin itself was not dissolved or digested. Nor is it
digested by the gastric juice of living animals, and according to
Schiff* it is a layer of this substance which protects the coats of the
stomach from being corroded during digestion.

Pepsin.--My experiments are hardly worth giving, as it is scarcely
possible to prepare pepsin free from other albuminoids; but I was
curious to ascertain, as far as that was possible, whether the ferment
of the secretion of Drosera would act on the ferment of the gastric
juice of animals. I first used the common pepsin sold for medicinal
purposes, and afterwards some which was much purer, prepared for me by
Dr. Moore. Five leaves to which a considerable quantity of the former
was given remained inflected for five days; four of them then died,
apparently from too great stimulation. I then tried Dr. Moore's pepsin,
making it into a paste with water, and placing such small particles on
the discs of five leaves that all would have been quickly dissolved had
it been meat or albumen. The leaves were soon inflected; two of them
began to re-expand after only 20 hrs., and the other three were almost
completely re-expanded after 44 hrs. Some of the glands which had been
in contact with the particles of pepsin, or with the acid secretion
surrounding them, were singularly pale, whereas others were singularly
dark-coloured. Some of the secretion was scraped off and examined under
a high power; and it abounded with granules undistinguishable from
those of pepsin left in water for the same length of time. We may
therefore infer, as highly probable (remembering what small quantities
were given), that the ferment of Drosera does not act on or digest

* 'Leons phys. de la Digestion,' 1867, tom. ii., p. 304.  [page 124]

pepsin, but absorbs from it some albuminous impurity which induces
inflection, and which in large quantity is highly injurious. Dr. Lauder
Brunton at my request endeavoured to ascertain whether pepsin with
hydrochloric acid would digest pepsin, and as far as he could judge, it
had no such power. Gastric juice, therefore, apparently agrees in this
respect with the secretion of Drosera.

Urea.--It seemed to me an interesting inquiry whether this refuse of
the living body, which contains much nitrogen, would, like so many
other animal fluids and substances, be absorbed by the glands of
Drosera and cause inflection. Half-minim drops of a solution of one
part to 437 of water were placed on the discs of four leaves, each drop
containing the quantity usually employed by me, namely 1/960 of a
grain, or .0674 mg.; but the leaves were hardly at all affected. They
were then tested with bits of meat, and soon became closely inflected.
I repeated the same experiment on four leaves with some fresh urea
prepared by Dr. Moore; after two days there was no inflection; I then
gave them another dose, but still there was no inflection. These leaves
were afterwards tested with similarly sized drops of an infusion of raw
meat, and in 6 hrs. there was considerable inflection, which became
excessive in 24 hrs.  But the urea apparently was not quite pure, for
when four leaves were immersed in 2 dr. (7.1 ml.) of the solution, so
that all the glands, instead of merely those on the disc, were enabled
to absorb any small amount of impurity in solution, there was
considerable inflection after 24 hrs., certainly more than would have
followed from a similar immersion in pure water. That the urea, which
was not perfectly white, should have contained a sufficient quantity of
albuminous matter, or of some salt of ammonia, to have caused the above
effect, is far from surprising, for, as we shall see in the next
chapter, astonishingly small doses of ammonia are highly efficient. We
may therefore conclude that urea itself is not exciting or nutritious
to Drosera; nor is it modified by the secretion, so as to be rendered
nutritious, for, had this been the case, all the leaves with drops on
their discs assuredly would have been well inflected.  Dr. Lauder
Brunton informs me that from experiments made at my request at St.
Bartholomew's Hospital it appears that urea is not acted on by
artificial gastric juice, that is by pepsin with hydrochloric acid.

Chitine.--The chitinous coats of insects naturally captured by the
leaves do not appear in the least corroded. Small square pieces of the
delicate wing and of the elytron of a Staphylinus [page 125] were
placed on some leaves, and after these had re-expanded, the pieces were
carefully examined. Their angles were as sharp as ever, and they did
not differ in appearance from the other wing and elytron of the same
insect which had been left in water. The elytron, however, had
evidently yielded some nutritious matter, for the leaf remained clasped
over it for four days; whereas the leaves with bits of the true wing
re-expanded on the second day. Any one who will examine the excrement
of insect-eating animals will see how powerless their gastric juice is
on chitine.

Cellulose.--I did not obtain this substance in a separate state, but
tried angular bits of dry wood, cork, sphagnum moss, linen, and cotton
thread. None of these bodies were in the least attacked by the
secretion, and they caused only that moderate amount of inflection
which is common to all inorganic objects. Gun-cotton, which consists of
cellulose, with the hydrogen replaced by nitrogen, was tried with the
same result. We have seen that a decoction of cabbage-leaves excites
the most powerful inflection. I therefore placed two little square bits
of the blade of a cabbage-leaf, and four little cubes cut from the
midrib, on six leaves of Drosera. These became well inflected in 12
hrs., and remained so for between two and four days; the bits of
cabbage being bathed all the time by acid secretion. This shows that
some exciting matter, to which I shall presently refer, had been
absorbed; but the angles of the squares and cubes remained as sharp as
ever, proving that the framework of cellulose had not been attacked.
Small square bits of spinach-leaves were tried with the same result;
the glands pouring forth a moderate supply of acid secretion, and the
tentacles remaining inflected for three days. We have also seen that
the delicate coats of pollen grains are not dissolved by the secretion.
It is well known that the gastric juice of animals does not attack
cellulose.

Chlorophyll.--This substance was tried, as it contains nitrogen. Dr.
Moore sent me some preserved in alcohol; it was dried, but soon
deliquesced. Particles were placed on four leaves; after 3 hrs. the
secretion was acid; after 8 hrs. there was a good deal of inflection,
which in 24 hrs. became fairly well marked. After four days two of the
leaves began to open, and the other two were then almost fully
re-expanded. It is therefore clear that this chlorophyll contained
matter which excited the leaves to a moderate degree; but judging by
the eye, little or none was dissolved; so that in a pure state it would
not probably have been attacked by the secretion. Dr. Sanderson tried
that which I [page 126] used, as well as some freshly prepared, with
artificial digestive liquid, and found that it was not digested. Dr.
Lauder Brunton likewise tried some prepared by the process given in the
British Pharmacopoeia, and exposed it for five days at the temperature
of 37o Cent. to digestive liquid, but it was not diminished in bulk,
though the fluid acquired a slightly brown colour. It was also tried
with the glycerine extract of pancreas with a negative result. Nor does
chlorophyll seem affected by the intestinal secretions of various
animals, judging by the colour of their excrement.

It must not be supposed from these facts that the grains of
chlorophyll, as they exist in living plants, cannot be attacked by the
secretion; for these grains consist of protoplasm merely coloured by
chlorophyll. My son Francis placed a thin slice of spinach leaf,
moistened with saliva, on a leaf of Drosera, and other slices on damp
cotton-wool, all exposed to the same temperature. After 19 hrs. the
slice on the leaf of Drosera was bathed in much secretion from the
inflected tentacles, and was now examined under the microscope. No
perfect grains of chlorophyll could be distinguished; some were
shrunken, of a yellowish-green colour, and collected in the middle of
the cells; others were disintegrated and formed a yellowish mass,
likewise in the middle of the cells. On the other hand, in the slices
surrounded by damp cotton-wool, the grains of chlorophyll were green
and as perfect as ever. My son also placed some slices in artificial
gastric juice, and these were acted on in nearly the same manner as by
the secretion. We have seen that bits of fresh cabbage and spinach
leaves cause the tentacles to be inflected and the glands to pour forth
much acid secretion; and there can be little doubt that it is the
protoplasm forming the grains of chlorophyll, as well as that lining
the walls of the cells, which excites the leaves.

Fat and Oil.--Cubes of almost pure uncooked fat, placed on several
leaves, did not have their angles in the least rounded. We have also
seen that the oil-globules in milk are not digested.  Nor does olive
oil dropped on the discs of leaves cause any inflection; but when they
are immersed in olive oil, they become strongly inflected; but to this
subject I shall have to recur.  Oily substances are not digested by the
gastric juice of animals.

Starch.--Rather large bits of dry starch caused well-marked inflection,
and the leaves did not re-expand until the fourth day; but I have no
doubt that this was due to the prolonged irritation of the glands, as
the starch continued to absorb the secretion. The particles were not in
the least reduced in size; [page 127] and we know that leaves immersed
in an emulsion of starch are not at all affected. I need hardly say
that starch is not digested by the gastric juice of animals.

Action of the Secretion on Living Seeds.

The results of some experiments on living seeds, selected by hazard,
may here be given, though they bear only indirectly on our present
subject of digestion.

Seven cabbage seeds of the previous year were placed on the same number
of leaves. Some of these leaves were moderately, but the greater number
only slightly inflected, and most of them re-expanded on the third day.
One, however, remained clasped till the fourth, and another till the
fifth day. These leaves therefore were excited somewhat more by the
seeds than by inorganic objects of the same size. After they
re-expanded, the seeds were placed under favourable conditions on damp
sand; other seeds of the same lot being tried at the same time in the
same manner, and found to germinate well. Of the seven seeds which had
been exposed to the secretion, only three germinated; and one of the
three seedlings soon perished, the tip of its radicle being from the
first decayed, and the edges of its cotyledons of a dark brown colour;
so that altogether five out of the seven seeds ultimately perished.

Radish seeds (Raphanus sativus) of the previous year were placed on
three leaves, which became moderately inflected, and re-expanded on the
third or fourth day. Two of these seeds were transferred to damp sand;
only one germinated, and that very slowly. This seedling had an
extremely short, crooked, diseased, radicle, with no absorbent hairs;
and the cotyledons were oddly mottled with purple, with the edges
blackened and partly withered.

Cress seeds (Lepidum sativum) of the previous year were placed on four
leaves; two of these next morning were moderately and two strongly
inflected, and remained so for four, five, and even six days. Soon
after these seeds were placed on the leaves and had become damp, they
secreted in the usual manner a layer of tenacious mucus; and to
ascertain whether it was the absorption of this substance by the glands
which caused so much inflection, two seeds were put into water, and as
much of the mucus as possible scraped off. They were then placed on
leaves, which became very strongly inflected in the course of 3 hrs.,
and were still closely inflected on the third day; so that it evidently
was not the mucus which excited so [page 128] much inflection; on the
contrary, this served to a certain extent as a protection to the
seeds.  Two of the six seeds germinated whilst still lying on the
leaves, but the seedlings, when transferred to damp sand, soon died; of
the other four seeds, only one germinated.

Two seeds of mustard (Sinapis nigra), two of celery (Apium
graveolens)--both of the previous year, two seeds well soaked of
caraway (Carum carui), and two of wheat, did not excite the leaves more
than inorganic objects often do. Five seeds, hardly ripe, of a
buttercup (Ranunculus), and two fresh seeds of Anemone nemorosa,
induced only a little more effect.  On the other hand, four seeds,
perhaps not quite ripe, of Carex sylvatica caused the leaves on which
they were placed to be very strongly inflected; and these only began to
re-expand on the third day, one remaining inflected for seven days.

It follows from these few facts that different kinds of seeds excite
the leaves in very different degrees; whether this is solely due to the
nature of their coats is not clear. In the case of the cress seeds, the
partial removal of the layer of mucus hastened the inflection of the
tentacles.  Whenever the leaves remain inflected during several days
over seeds, it is clear that they absorb some matter from them. That
the secretion penetrates their coats is also evident from the large
proportion of cabbage, raddish, and cress seeds which were killed, and
from several of the seedlings being greatly injured. This injury to the
seeds and seedlings may, however, be due solely to the acid of the
secretion, and not to any process of digestion; for Mr.  Traherne
Moggridge has shown that very weak acids of the acetic series are
highly injurious to seeds. It never occurred to me to observe whether
seeds are often blown on to the viscid leaves of plants growing in a
state of nature; but this can hardly fail sometimes to occur, as we
shall hereafter see in the case of Pinguicula. If so, Drosera will
profit to a slight degree by absorbing matter from such seeds.]

Summary and Concluding Remarks on the Digestive Power of Drosera.

When the glands on the disc are excited either by the absorption of
nitrogenous matter or by mechanical irritation, their secretion
increases in quantity and becomes acid. They likewise transmit [page
129] some influence to the glands of the exterior tentacles, causing
them to secrete more copiously; and their secretion likewise becomes
acid.  With animals, according to Schiff,* mechanical irritation
excites the glands of the stomach to secrete an acid, but not pepsin.
Now, I have every reason to believe (though the fact is not fully
established), that although the glands of Drosera are continually
secreting viscid fluid to replace that lost by evaporation, yet they do
not secrete the ferment proper for digestion when mechanically
irritated, but only after absorbing certain matter, probably of a
nitrogenous nature. I infer that this is the case, as the secretion
from a large number of leaves which had been irritated by particles of
glass placed on their discs did not digest albumen; and more especially
from the analogy of Dionaea and Nepenthes. In like manner, the glands
of the stomach of animals secrete pepsin, as Schiff asserts, only after
they have absorbed certain soluble substances, which he designates as
peptogenes. There is, therefore, a remarkable parallelism between the
glands of Drosera and those of the stomach in the secretion of their
proper acid and ferment.

The secretion, as we have seen, completely dissolves albumen, muscle,
fibrin, areolar tissue, cartilage, the fibrous basis of bone, gelatine,
chondrin, casein in the state in which it exists in milk, and gluten
which has been subjected to weak hydrochloric acid. Syntonin and
legumin excite the leaves so powerfully and quickly that there can
hardly be a doubt that both would be dissolved by the secretion. The
secretion

* 'Phys. de la Digestion,' 1867, tom. ii. pp. 188, 245.  [page 130]

failed to digest fresh gluten, apparently from its injuring the glands,
though some was absorbed. Raw meat, unless in very small bits, and
large pieces of albumen, &c., likewise injure the leaves, which seem to
suffer, like animals, from a surfeit. I know not whether the analogy is
a real one, but it is worth notice that a decoction of cabbage leaves
is far more exciting and probably nutritious to Drosera than an
infusion made with tepid water; and boiled cabbages are far more
nutritious, at least to man, than the uncooked leaves. The most
striking of all the cases, though not really more remarkable than many
others, is the digestion of so hard and tough a substance as cartilage.
The dissolution of pure phosphate of lime, of bone, dentine, and
especially enamel, seems wonderful; but it depends merely on the
long-continued secretion of an acid; and this is secreted for a longer
time under these circumstances than under any others. It was
interesting to observe that as long as the acid was consumed in
dissolving the phosphate of lime, no true digestion occurred; but that
as soon as the bone was completely decalcified, the fibrous basis was
attacked and liquefied with the greatest ease. The twelve substances
above enumerated, which are completely dissolved by the secretion, are
likewise dissolved by the gastric juice of the higher animals; and they
are acted on in the same manner, as shown by the rounding of the angles
of albumen, and more especially by the manner in which the transverse
striae of the fibres of muscle disappear.

The secretion of Drosera and gastric juice were both able to dissolve
some element or impurity out of the globulin and haematin employed by
me. The secretion also dissolved something out of chemically [page 131]
prepared casein, which is said to consist of two substances; and
although Schiff asserts that casein in this state is not attacked by
gastric juice, he might easily have overlooked a minute quantity of
some albuminous matter, which Drosera would detect and absorb. Again,
fibro-cartilage, though not properly dissolved, is acted on in the same
manner, both by the secretion of Drosera and gastric juice. But this
substance, as well as the so-called haematin used by me, ought perhaps
to have been classed with indigestible substances.

That gastric juice acts by means of its ferment, pepsin, solely in the
presence of an acid, is well established; and we have excellent
evidence that a ferment is present in the secretion of Drosera, which
likewise acts only in the presence of an acid; for we have seen that
when the secretion is neutralised by minute drops of the solution of an
alkali, the digestion of albumen is completely stopped, and that on the
addition of a minute dose of hydrochloric acid it immediately
recommences.

The nine following substances, or classes of substances, namely,
epidermic productions, fibro-elastic tissue, mucin, pepsin, urea,
chitine, cellulose, gun-cotton, chlorophyll, starch, fat and oil, are
not acted on by the secretion of Drosera; nor are they, as far as is
known, by the gastric juice of animals. Some soluble matter, however,
was extracted from the mucin, pepsin, and chlorophyll, used by me, both
by the secretion and by artificial gastric juice.

The several substances, which are completely dissolved by the
secretion, and which are afterwards absorbed by the glands, affect the
leaves rather differently. They induce inflection at very different
[page 132] rates and in very different degrees; and the tentacles
remain inflected for very different periods of time. Quick inflection
depends partly on the quantity of the substance given, so that many
glands are simultaneously affected, partly on the facility with which
it is penetrated and liquefied by the secretion, partly on its nature,
but chiefly on the presence of exciting matter already in solution.
Thus saliva, or a weak solution of raw meat, acts much more quickly
than even a strong solution of gelatine. So again leaves which have
re-expanded, after absorbing drops of a solution of pure gelatine or
isinglass (the latter being the more powerful of the two), if given
bits of meat, are inflected much more energetically and quickly than
they were before, notwithstanding that some rest is generally requisite
between two acts of inflection. We probably see the influence of
texture in gelatine and globulin when softened by having been soaked in
water acting more quickly than when merely wetted. It may be partly due
to changed texture, and partly to changed chemical nature, that
albumen, which had been kept for some time, and gluten which had been
subjected to weak hydrochloric acid, act more quickly than these
substances in their fresh state.

The length of time during which the tentacles remain inflected largely
depends on the quantity of the substance given, partly on the facility
with which it is penetrated or acted on by the secretion, and partly on
its essential nature. The tentacles always remain inflected much longer
over large bits or large drops than over small bits or drops. Texture
probably plays a part in determining the extraordinary length of time
during which the tentacles remain inflected [page 133] over the hard
grains of chemically prepared casein. But the tentacles remain
inflected for an equally long time over finely powdered, precipitated
phosphate of lime; phosphorus in this latter case evidently being the
attraction, and animal matter in the case of casein. The leaves remain
long inflected over insects, but it is doubtful how far this is due to
the protection afforded by their chitinous integuments; for animal
matter is soon extracted from insects (probably by exosmose from their
bodies into the dense surrounding secretion), as shown by the prompt
inflection of the leaves. We see the influence of the nature of
different substances in bits of meat, albumen, and fresh gluten acting
very differently from equal-sized bits of gelatine, areolar tissue, and
the fibrous basis of bone. The former cause not only far more prompt
and energetic, but more prolonged, inflection than do the latter. Hence
we are, I think, justified in believing that gelatine, areolar tissue,
and the fibrous basis of bone, would be far less nutritious to Drosera
than such substances as insects, meat, albumen, &c. This is an
interesting conclusion, as it is known that gelatine affords but little
nutriment to animals; and so, probably, would areolar tissue and the
fibrous basis of bone. The chondrin which I used acted more powerfully
than gelatine, but then I do not know that it was pure. It is a more
remarkable fact that fibrin, which belongs to the great class of
Proteids,* including albumen in one of its sub-groups, does not excite
the tentacles in a greater degree, or keep them inflected for a longer
time, than does gelatine, or

* See the classification adopted by Dr. Michael Foster in Watts'
'Dictionary of Chemistry,' Supplement 1872, page 969.  [page 134]

areolar tissue, or the fibrous basis of bone. It is not known how long
an animal would survive if fed on fibrin alone, but Dr. Sanderson has
no doubt longer than on gelatine, and it would be hardly rash to
predict, judging from the effects on Drosera, that albumen would be
found more nutritious than fibrin. Globulin likewise belongs to the
Proteids, forming another sub-group, and this substance, though
containing some matter which excited Drosera rather strongly, was
hardly attacked by the secretion, and was very little or very slowly
attacked by gastric juice. How far globulin would be nutritious to
animals is not known. We thus see how differently the above specified
several digestible substances act on Drosera; and we may infer, as
highly probable, that they would in like manner be nutritious in very
different degrees both to Drosera and to animals.

The glands of Drosera absorb matter from living seeds, which are
injured or killed by the secretion. They likewise absorb matter from
pollen, and from fresh leaves; and this is notoriously the case with
the stomachs of vegetable-feeding animals. Drosera is properly an
insectivorous plant; but as pollen cannot fail to be often blown on to
the glands, as will occasionally the seeds and leaves of surrounding
plants, Drosera is, to a certain extent, a vegetable-feeder.

Finally, the experiments recorded in this chapter show us that there is
a remarkable accordance in the power of digestion between the gastric
juice of animals with its pepsin and hydrochloric acid and the
secretion of Drosera with its ferment and acid belonging to the acetic
series. We can, therefore, hardly doubt that the ferment in both cases
is closely similar, [page 135] if not identically the same. That a
plant and an animal should pour forth the same, or nearly the same,
complex secretion, adapted for the same purpose of digestion, is a new
and wonderful fact in physiology. But I shall have to recur to this
subject in the fifteenth chapter, in my concluding remarks on the
Droseraceae.  [page 136]



                          CHAPTER VII.

                THE EFFECTS OF SALTS OF AMMONIA.

Manner of performing the experiments--Action of distilled water in
comparison with the solutions--Carbonate of ammonia, absorbed by the
roots--The vapour absorbed by the glands- -Drops on the disc--Minute
drops applied to separate glands--Leaves immersed in weak
solutions--Minuteness of the doses which induce aggregation of the
protoplasm--Nitrate of ammonia, analogous experiments with--Phosphate
of ammonia, analogous experiments with- -Other salts of
ammonia--Summary and concluding remarks on the action of salts of
ammonia.

THE chief object in this chapter is to show how powerfully the salts of
ammonia act on the leaves of Drosera, and more especially to show what
an extraordinarily small quantity suffices to excite inflection. I
shall, therefore, be compelled to enter into full details. Doubly
distilled water was always used; and for the more delicate experiments,
water which had been prepared with the utmost possible care was given
me by Professor Frankland. The graduated measures were tested, and
found as accurate as such measures can be. The salts were carefully
weighed, and in all the more delicate experiments, by Borda's double
method.  But extreme accuracy would have been superfluous, as the
leaves differ greatly in irritability, according to age, condition, and
constitution. Even the tentacles on the same leaf differ in
irritability to a marked degree. My experiments were tried in the
following several ways.

[Firstly.--Drops which were ascertained by repeated trials to be on an
average about half a minim, or the 1/960 of a fluid ounce (.0296 ml.),
were placed by the same pointed instrument on the [page 137] discs of
the leaves, and the inflection of the exterior rows of tentacles
observed at successive intervals of time. It was first ascertained,
from between thirty and forty trials, that distilled water dropped in
this manner produces no effect, except that sometimes, though rarely,
two or three tentacles become inflected. In fact all the many trials
with solutions which were so weak as to produce no effect lead to the
same result that water is inefficient.

Secondly.--The head of a small pin, fixed into a handle, was dipped
into the solution under trial. The small drop which adhered to it, and
which was much too small to fall off, was cautiously placed, by the aid
of a lens, in contact with the secretion surrounding the glands of one,
two, three, or four of the exterior tentacles of the same leaf. Great
care was taken that the glands themselves should not be touched. I had
supposed that the drops were of nearly the same size; but on trial this
proved a great mistake. I first measured some water, and removed 300
drops, touching the pin's head each time on blotting-paper; and on
again measuring the water, a drop was found to equal on an average
about the 1/60 of a minim. Some water in a small vessel was weighed
(and this is a more accurate method), and 300 drops removed as before;
and on again weighing the water, a drop was found to equal on an
average only the 1/89 of a minim. I repeated the operation, but
endeavoured this time, by taking the pin's head out of the water
obliquely and rather quickly, to remove as large drops as possible; and
the result showed that I had succeeded, for each drop on an average
equalled 1/19.4 of a minim. I repeated the operation in exactly the
same manner, and now the drops averaged 1/23.5 of a minim. Bearing in
mind that on these two latter occasions special pains were taken to
remove as large drops as possible, we may safely conclude that the
drops used in my experiments were at least equal to the 1/20 of a
minim, or .0029 ml. One of these drops could be applied to three or
even four glands, and if the tentacles became inflected, some of the
solution must have been absorbed by all; for drops of pure water,
applied in the same manner, never produced any effect. I was able to
hold the drop in steady contact with the secretion only for ten to
fifteen seconds; and this was not time enough for the diffusion of all
the salt in solution, as was evident, from three or four tentacles
treated successively with the same drop, often becoming inflected. All
the matter in solution was even then probably not exhausted.

Thirdly.--Leaves cut off and immersed in a measured [page 138] quantity
of the solution under trial; the same number of leaves being immersed
at the same time, in the same quantity of the distilled water which had
been used in making the solution.  The leaves in the two lots were
compared at short intervals of time, up to 24 hrs., and sometimes to 48
hrs. They were immersed by being laid as gently as possible in numbered
watch-glasses, and thirty minims (1.775 ml.) of the solution or of
water was poured over each.

Some solutions, for instance that of carbonate of ammonia, quickly
discolour the glands; and as all on the same leaf were discoloured
simultaneously, they must all have absorbed some of the salt within the
same short period of time. This was likewise shown by the simultaneous
inflection of the several exterior rows of tentacles. If we had no such
evidence as this, it might have been supposed that only the glands of
the exterior and inflected tentacles had absorbed the salt; or that
only those on the disc had absorbed it, and had then transmitted a
motor impulse to the exterior tentacles; but in this latter case the
exterior tentacles would not have become inflected until some time had
elapsed, instead of within half an hour, or even within a few minutes,
as usually occurred. All the glands on the same leaf are of nearly the
same size, as may best be seen by cutting off a narrow transverse
strip, and laying it on its side; hence their absorbing surfaces are
nearly equal. The long-headed glands on the extreme margin must be
excepted, as they are much longer than the others; but only the upper
surface is capable of absorption. Besides the glands, both surfaces of
the leaves and the pedicels of the tentacles bear numerous minute
papillae, which absorb carbonate of ammonia, an infusion of raw meat,
metallic salts, and probably many other substances, but the absorption
of matter by these papillae never induces inflection. We must remember
that the movement of each separate tentacle depends on its gland being
excited, except when a motor impulse is transmitted from the glands of
the disc, and then the movement, as just stated, does not take place
until some little time has elapsed. I have made these remarks because
they show us that when a leaf is immersed in a solution, and the
tentacles are inflected, we can judge with some accuracy how much of
the salt each gland has absorbed. For instance, if a leaf bearing 212
glands be immersed in a measured quantity of a solution, containing
1/10 of a grain of a salt, and all the exterior tentacles, except
twelve, are inflected, we may feel sure that each of the 200 glands can
on an average have absorbed at most 1/2000 of a grain of the salt. I
say at [page 139] most, for the papillae will have absorbed some small
amount, and so will perhaps the glands of the twelve excluded tentacles
which did not become inflected. The application of this principle leads
to remarkable conclusions with respect to the minuteness of the doses
causing inflection.

    On the Action of Distilled Water in Causing Inflection.

Although in all the more important experiments the difference between
the leaves simultaneously immersed in water and in the several
solutions will be described, nevertheless it may be well here to give a
summary of the effects of water. The fact, moreover, of pure water
acting on the glands deserves in itself some notice. Leaves to the
number of 141 were immersed in water at the same time with those in the
solutions, and their state recorded at short intervals of time.
Thirty-two other leaves were separately observed in water, making
altogether 173 experiments. Many scores of leaves were also immersed in
water at other times, but no exact record of the effects produced was
kept; yet these cursory observations support the conclusions arrived at
in this chapter. A few of the long-headed tentacles, namely from one to
about six, were commonly inflected within half an hour after immersion;
as were occasionally a few, and rarely a considerable number of the
exterior round-headed tentacles.  After an immersion of from 5 to 8
hrs. the short tentacles surrounding the outer parts of the disc
generally become inflected, so that their glands form a small dark ring
on the disc; the exterior tentacles not partaking of this movement.
Hence, excepting in a few cases hereafter to be specified, we can judge
whether a solution produces any effect only by observing the exterior
tentacles within the first 3 or 4 hrs. after immersion.

Now for a summary of the state of the 173 leaves after an immersion of
3 or 4 hrs. in pure water. One leaf had almost all its tentacles
inflected; three leaves had most of them sub-inflected; and thirteen
had on an average 36.5 tentacles inflected. Thus seventeen leaves out
of the 173 were acted on in a marked manner. Eighteen leaves had from
seven to nineteen tentacles inflected, the average being 9.3 tentacles
for each leaf. Forty-four leaves had from one to six tentacles
inflected, generally the long-headed ones. So that altogether of the
173 leaves carefully observed, seventy-nine were affected by the water
in some degree, though commonly to a very slight degree; and
ninety-four were not affected in the least degree. This [page 140]
amount of inflection is utterly insignificant, as we shall hereafter
see, compared with that caused by very weak solutions of several salts
of ammonia.

Plants which have lived for some time in a rather high temperature are
far more sensitive to the action of water than those grown out of
doors, or recently brought into a warm greenhouse. Thus in the above
seventeen cases, in which the immersed leaves had a considerable number
of tentacles inflected, the plants had been kept during the winter in a
very warm greenhouse; and they bore in the early spring remarkably fine
leaves, of a light red colour. Had I then known that the sensitiveness
of plants was thus increased, perhaps I should not have used the leaves
for my experiments with the very weak solutions of phosphate of
ammonia; but my experiments are not thus vitiated, as I invariably used
leaves from the same plants for simultaneous immersion in water. It
often happened that some leaves on the same plant, and some tentacles
on the same leaf, were more sensitive than others; but why this should
be so, I do not know.

FIG. 9.  (Drosera rotundifolia.) Leaf (enlarged) with all the tentacles
closely inflected, from immersion in a solution of phosphate of ammonia
(one part to 87,500 of water.)

Besides the differences just indicated between the leaves immersed in
water and in weak solutions of ammonia, the tentacles of the latter are
in most cases much more closely inflected. The appearance of a leaf
after immersion in a few drops of a solution of 1 grain of phosphate of
ammonia to 200 oz. of water (i.e. one part to 87,500) is here
reproduced: such energetic inflection is never caused by water alone.
With leaves in the weak solutions, the blade or lamina often becomes
inflected; and this is so rare a circumstance with leaves in water that
I have seen only two instances; and in both of these the inflection was
very feeble.  Again, with leaves in the weak solutions, the inflection
of the tentacles and blade often goes on steadily, though slowly,
increasing during many hours; and [page 141] this again is so rare a
circumstance with leaves in water that I have seen only three instances
of any such increase after the first 8 to 12 hrs.; and in these three
instances the two outer rows of tentacles were not at all affected.
Hence there is sometimes a much greater difference between the leaves
in water and in the weak solutions, after from 8 hrs. to 24 hrs., than
there was within the first 3 hrs.; though as a general rule it is best
to trust to the difference observed within the shorter time.

With respect to the period of the re-expansion of the leaves, when left
immersed either in water or in the weak solutions, nothing could be
more variable. In both cases the exterior tentacles not rarely begin to
re-expand, after an interval of only from 6 to 8 hrs.; that is just
about the time when the short tentacles round the borders of the disc
become inflected. On the other hand, the tentacles sometimes remain
inflected for a whole day, or even two days; but as a general rule they
remain inflected for a longer period in very weak solutions than in
water. In solutions which are not extremely weak, they never re-expand
within nearly so short a period as six or eight hours. From these
statements it might be thought difficult to distinguish between the
effects of water and the weaker solutions; but in truth there is not
the slightest difficulty until excessively weak solutions are tried;
and then the distinction, as might be expected, becomes very doubtful,
and at last disappears. But as in all, except the simplest, cases the
state of the leaves simultaneously immersed for an equal length of time
in water and in the solutions will be described, the reader can judge
for himself.]

                     CARBONATE OF AMMONIA.

This salt, when absorbed by the roots, does not cause the tentacles to
be inflected. A plant was so placed in a solution of one part of the
carbonate to 146 of water that the young uninjured roots could be
observed. The terminal cells, which were of a pink colour, instantly
became colourless, and their limpid contents cloudy, like a mezzo-tinto
engraving, so that some degree of aggregation was almost instantly
caused; but no further change ensued, and the absorbent hairs were not
visibly affected. The tentacles [page 142] did not bend. Two other
plants were placed with their roots surrounded by damp moss, in half an
ounce (14.198 ml.) of a solution of one part of the carbonate to 218 of
water, and were observed for 24 hrs.; but not a single tentacle was
inflected. In order to produce this effect, the carbonate must be
absorbed by the glands.

The vapour produces a powerful effect on the glands, and induces
inflection. Three plants with their roots in bottles, so that the
surrounding air could not have become very humid, were placed under a
bell-glass (holding 122 fluid ounces), together with 4 grains of
carbonate of ammonia in a watch-glass. After an interval of 6 hrs. 15
m. the leaves appeared unaffected; but next morning, after 20 hrs., the
blackened glands were secreting copiously, and most of the tentacles
were strongly inflected. These plants soon died. Two other plants were
placed under the same bell-glass, together with half a grain of the
carbonate, the air being rendered as damp as possible; and in 2 hrs.
most of the leaves were affected, many of the glands being blackened
and the tentacles inflected. But it is a curious fact that some of the
closely adjoining tentacles on the same leaf, both on the disc and
round the margins, were much, and some, apparently, not in the least
affected. The plants were kept under the bell-glass for 24 hrs., but no
further change ensued. One healthy leaf was hardly at all affected,
though other leaves on the same plant were much affected. On some
leaves all the tentacles on one side, but not those on the opposite
side, were inflected. I doubt whether this extremely unequal action can
be explained by supposing that the more active glands absorb all the
vapour as quickly as it is generated, so that none is left for the
others, for we shall meet with [page 143] analogous cases with air
thoroughly permeated with the vapours of chloroform and ether.

Minute particles of the carbonate were added to the secretion
surrounding several glands.  These instantly became black and secreted
copiously; but, except in two instances, when extremely minute
particles were given, there was no inflection. This result is analogous
to that which follows from the immersion of leaves in a strong solution
of one part of the carbonate to 109, or 146, or even 218 of water, for
the leaves are then paralysed and no inflection ensues, though the
glands are blackened, and the protoplasm in the cells of the tentacles
undergoes strong aggregation.

[We will now turn to the effects of solutions of the carbonate.
Half-minims of a solution of one part to 437 of water were placed on
the discs of twelve leaves; so that each received 1/960 of a grain or
.0675 mg. Ten of these had their tentacles well inflected; the blades
of some being also much curved inwards. In two cases several of the
exterior tentacles were inflected in 35 m.; but the movement was
generally slower. These ten leaves re-expanded in periods varying
between 21 hrs. and 45 hrs., but in one case not until 67 hrs. had
elapsed; so that they re-expanded much more quickly than leaves which
have caught insects.

The same-sized drops of a solution of one part to 875 of water were
placed on the discs of eleven leaves; six remained quite unaffected,
whilst five had from three to six or eight of their exterior tentacles
inflected; but this degree of movement can hardly be considered as
trustworthy. Each of these leaves received 1/1920 of a grain (.0337
mg.), distributed between the glands of the disc, but this was too
small an amount to produce any decided effect on the exterior
tentacles, the glands of which had not themselves received any of the
salt.

Minute drops on the head of a small pin, of a solution of one part of
the carbonate to 218 of water, were next tried in the manner above
described. A drop of this kind equals on an average 1/20 of a minim,
and therefore contains 1/4800 of a grain (.0135 mg.) of the carbonate.
I touched with it the viscid secretion round three glands, so that each
gland received only [page 144] 1/14400 of a grain (.00445 mg.).
Nevertheless, in two trials all the glands were plainly blackened; in
one case all three tentacles were well inflected after an interval of 2
hrs. 40 m.; and in another case two of the three tentacles were
inflected. I then tried drops of a weaker solution of one part to 292
of water on twenty-four glands, always touching the viscid secretion
round three glands with the same little drop. Each gland thus received
only the 1/19200 of a grain (.00337 mg.), yet some of them were a
little darkened; but in no one instance were any of the tentacles
inflected, though they were watched for 12 hrs. When a still weaker
solution (viz. one part to 437 of water) was tried on six glands, no
effect whatever was perceptible. We thus learn that the 1/14400 of a
grain (.00445 mg.) of carbonate of ammonia, if absorbed by a gland,
suffices to induce inflection in the basal part of the same tentacle;
but as already stated, I was able to hold with a steady hand the minute
drops in contact with the secretion only for a few seconds; and if more
time had been allowed for diffusion and absorption, a much weaker
solution would certainly have acted.

Some experiments were made by immersing cut-off leaves in solutions of
different strengths.  Thus four leaves were left for about 3 hrs. each
in a drachm (3.549 ml.) of a solution of one part of the carbonate to
5250 of water; two of these had almost every tentacle inflected, the
third had about half the tentacles and the fourth about one-third
inflected; and all the glands were blackened. Another leaf was placed
in the same quantity of a solution of one part to 7000 of water, and in
1 hr. 16 m. every single tentacle was well inflected, and all the
glands blackened. Six leaves were immersed, each in thirty minims
(1.774 ml.) of a solution of one part to 4375 of water, and the glands
were all blackened in 31 m. All six leaves exhibited some slight
inflection, and one was strongly inflected. Four leaves were then
immersed in thirty minims of a solution of one part to 8750 of water,
so that each leaf received the 1/320 of a grain (.2025 mg.). Only one
became strongly inflected; but all the glands on all the leaves were of
so dark a red after one hour as almost to deserve to be called black,
whereas this did not occur with the leaves which were at the same time
immersed in water; nor did water produce this effect on any other
occasion in nearly so short a time as an hour. These cases of the
simultaneous darkening or blackening of the glands from the action of
weak solutions are important, as they show that all the glands absorbed
the carbonate within the same time, which fact indeed there was not the
least reason to doubt. So again, whenever all the [page 145] tentacles
become inflected within the same time, we have evidence, as before
remarked, of simultaneous absorption. I did not count the number of
glands on these four leaves; but as they were fine ones, and as we know
that the average number of glands on thirty-one leaves was 192, we may
safely assume that each bore on an average at least 170; and if so,
each blackened gland could have absorbed only 1/54400 of a grain
(.00119 mg.) of the carbonate.

A large number of trials had been previously made with solutions of one
part of the nitrate and phosphate of ammonia to 43750 of water (i.e.
one grain to 100 ounces), and these were found highly efficient.
Fourteen leaves were therefore placed, each in thirty minims of a
solution of one part of the carbonate to the above quantity of water;
so that each leaf received 1/1600 of a grain (.0405 mg.). The glands
were not much darkened. Ten of the leaves were not affected, or only
very slightly so. Four, however, were strongly affected; the first
having all the tentacles, except forty, inflected in 47 m.; in 6 hrs.
30 m. all except eight; and after 4 hrs. the blade itself. The second
leaf after 9 m. had all its tentacles except nine inflected; after 6
hrs. 30 m. these nine were sub-inflected; the blade having become much
inflected in 4 hrs. The third leaf after 1 hr. 6 m. had all but forty
tentacles inflected. The fourth, after 2 hrs.  5 m., had about half its
tentacles and after 4 hrs. all but forty-five inflected. Leaves which
were immersed in water at the same time were not at all affected, with
the exception of one; and this not until 8 hrs. had elapsed. Hence
there can be no doubt that a highly sensitive leaf, if immersed in a
solution, so that all the glands are enabled to absorb, is acted on by
1/1600 of a grain of the carbonate. Assuming that the leaf, which was a
large one, and which had all its tentacles excepting eight inflected,
bore 170 glands, each gland could have absorbed only 1/268800 of a
grain (.00024 mg.); yet this sufficed to act on each of the 162
tentacles which were inflected. But as only four out of the above
fourteen leaves were plainly affected, this is nearly the minimum dose
which is efficient.

Aggregation of the Protoplasm from the Action of Carbonate of
Ammonia.--I have fully described in the third chapter the remarkable
effects of moderately strong doses of this salt in causing the
aggregation of the protoplasm within the cells of the glands and
tentacles; and here my object is merely to show what small doses
suffice. A leaf was immersed in twenty minims (1.183 ml.) of a solution
of one part to 1750 of water, [page 146] and another leaf in the same
quantity of a solution of one part to 3062; in the former case
aggregation occurred in 4 m., in the latter in 11 m. A leaf was then
immersed in twenty minims of a solution of one part to 4375 of water,
so that it received 1/240 of a grain (.27 mg.); in 5 m. there was a
slight change of colour in the glands, and in 15 m. small spheres of
protoplasm were formed in the cells beneath the glands of all the
tentacles. In these cases there could not be a shadow of a doubt about
the action of the solution.

A solution was then made of one part to 5250 of water, and I
experimented on fourteen leaves, but will give only a few of the cases.
Eight young leaves were selected and examined with care, and they
showed no trace of aggregation. Four of these were placed in a drachm
(3.549 ml.) of distilled water; and four in a similar vessel, with a
drachm of the solution.  After a time the leaves were examined under a
high power, being taken alternately from the solution and the water.
The first leaf was taken out of the solution after an immersion of 2
hrs. 40 m., and the last leaf out of the water after 3 hrs. 50 m.; the
examination lasting for 1 hr. 40 m. In the four leaves out of the water
there was no trace of aggregation except in one specimen, in which a
very few, extremely minute spheres of protoplasm were present beneath
some of the round glands. All the glands were translucent and red. The
four leaves which had been immersed in the solution, besides being
inflected, presented a widely different appearance; for the contents of
the cells of every single tentacle on all four leaves were
conspicuously aggregated; the spheres and elongated masses of
protoplasm in many cases extending halfway down the tentacles. All the
glands, both those of the central and exterior tentacles, were opaque
and blackened; and this shows that all had absorbed some of the
carbonate. These four leaves were of very nearly the same size, and the
glands were counted on one and found to be 167. This being the case,
and the four leaves having been immersed in a drachm of the solution,
each gland could have received on an average only 1/64128 of a grain
(.001009 mg.) of the salt; and this quantity sufficed to induce within
a short time conspicuous aggregation in the cells beneath all the
glands.

A vigorous but rather small red leaf was placed in six minims of the
same solution (viz. one part to 5250 of water), so that it received
1/960 of a grain (.0675 mg.). In 40 m. the glands appeared rather
darker; and in 1 hr. from four to six spheres of protoplasm were formed
in the cells beneath the glands of all the tentacles. I did not count
the tentacles, but we may [page 147] safely assume that there were at
least 140; and if so, each gland could have received only the 1/134400
of a grain, or .00048 mg.

A weaker solution was then made of one part to 7000 of water, and four
leaves were immersed in it; but I will give only one case. A leaf was
placed in ten minims of this solution; after 1 hr. 37 m. the glands
became somewhat darker, and the cells beneath all of them now contained
many spheres of aggregated protoplasm. This leaf received 1/768 of a
grain, and bore 166 glands. Each gland could, therefore, have received
only 1/127488 of a grain (.00507 mg.) of the carbonate.

Two other experiments are worth giving. A leaf was immersed for 4 hrs.
15 m. in distilled water, and there was no aggregation; it was then
placed for 1 hr. 15 m. in a little solution of one part to 5250 of
water; and this excited well-marked aggregation and inflection. Another
leaf, after having been immersed for 21 hrs. 15 m. in distilled water,
had its glands blackened, but there was no aggregation in the cells
beneath them; it was then left in six minims of the same solution, and
in 1 hr. there was much aggregation in many of the tentacles; in 2 hrs.
all the tentacles (146 in number) were affected--the aggregation
extending down for a length equal to half or the whole of the glands.
It is extremely improbable that these two leaves would have undergone
aggregation if they had been left for a little longer in the water,
namely for 1 hr. and 1 hr. 15 m., during which time they were immersed
in the solution; for the process of aggregation seems invariably to
supervene slowly and very gradually in water.]

Summary of the Results with Carbonate of Ammonia.--The roots absorb the
solution, as shown by their changed colour, and by the aggregation of
the contents of their cells. The vapour is absorbed by the glands;
these are blackened, and the tentacles are inflected. The glands of the
disc, when excited by a half-minim drop (.0296 ml.), containing 1/960
of a grain (.0675 mg.), transmit a motor impulse to the exterior
tentacles, causing them to bend inwards. A minute drop, containing
1/14400 of a grain (.00445 mg.), if held for a few seconds in contact
with a gland, soon causes the tentacle bearing it to be inflected. If a
leaf is left [page 148] immersed for a few hours in a solution, and a
gland absorbs the 1/134400 of a grain (.0048 mg.), its colour becomes
darker, though not actually black; and the contents of the cells
beneath the gland are plainly aggregated. Lastly, under the same
circumstances, the absorption by a gland of the 1/268800 of a grain
(.00024 mg.) suffices to excite the tentacle bearing this gland into
movement.

                     [NITRATE OF AMMONIA.

With the salt I attended only to the inflection of the leaves, for it
is far less efficient than the carbonate in causing aggregation,
although considerably more potent in causing inflection. I experimented
with half-minims (.0296 ml.) on the discs of fifty-two leaves, but will
give only a few cases. A solution of one part to 109 of water was too
strong, causing little inflection, and after 24 hrs. killing, or nearly
killing, four out of six leaves which were thus tried; each of which
received the 1/240 of a grain (or .27 mg.). A solution of one part to
218 of water acted most energetically, causing not only the tentacles
of all the leaves, but the blades of some, to be strongly inflected.
Fourteen leaves were tried with drops of a solution of one part to 875
of water, so that the disc of each received the 1/1920 of a grain
(.0337 mg.). Of these leaves, seven were very strongly acted on, the
edges being generally inflected; two were moderately acted on; and five
not at all. I subsequently tried three of these latter five leaves with
urine, saliva, and mucus, but they were only slightly affected; and
this proves that they were not in an active condition. I mention this
fact to show how necessary it is to experiment on several leaves. Two
of the leaves, which were well inflected, re-expanded after 51 hrs.

In the following experiment I happened to select very sensitive leaves.
Half-minims of a solution of one part to 1094 of water (i.e. 1 gr. to 2
1/2 oz.) were placed on the discs of nine leaves, so that each received
the 1/2400 of a grain (.027 mg.). Three of them had their tentacles
strongly inflected and their blades curled inwards; five were slightly
and somewhat doubtfully affected, having from three to eight of their
exterior tentacles inflected: one leaf was not at all affected, yet was
afterwards acted on by saliva. In six of these cases, a trace of action
was perceptible in [page 149] 7 hrs., but the full effect was not
produced until from 24 hrs. to 30 hrs. had elapsed. Two of the leaves,
which were only slightly inflected, re-expanded after an additional
interval of 19 hrs.

Half-minims of a rather weaker solution, viz. of one part to 1312 of
water (1 gr. to 3 oz.) were tried on fourteen leaves; so that each
received 1/2880 of a grain (.0225 mg.), instead of, as in the last
experiment, 1/2400 of a grain. The blade of one was plainly inflected,
as were six of the exterior tentacles; the blade of a second was
slightly, and two of the exterior tentacles well, inflected, all the
other tentacles being curled in at right angles to the disc; three
other leaves had from five to eight tentacles inflected; five others
only two or three, and occasionally, though very rarely, drops of pure
water cause this much action; the four remaining leaves were in no way
affected, yet three of them, when subsequently tried with urine, became
greatly inflected. In most of these cases a slight effect was
perceptible in from 6 hrs. to 7 hrs., but the full effect was not
produced until from 24 hrs. to 30 hrs. had elapsed.  It is obvious that
we have here reached very nearly the minimum amount, which, distributed
between the glands of the disc, acts on the exterior tentacles; these
having themselves not received any of the solution.

In the next place, the viscid secretion round three of the exterior
glands was touched with the same little drop (1/20 of a minim) of a
solution of one part to 437 of water; and after an interval of 2 hrs.
50 m. all three tentacles were well inflected. Each of these glands
could have received only the 1/28800 of a grain, or .00225 mg. A little
drop of the same size and strength was also applied to four other
glands, and in 1 hr. two became inflected, whilst the other two never
moved. We here see, as in the case of the half-minims placed on the
discs, that the nitrate of ammonia is more potent in causing inflection
than the carbonate; for minute drops of the latter salt of this
strength produced no effect. I tried minute drops of a still weaker
solution of the nitrate, viz. one part to 875 of water, on twenty-one
glands, but no effect whatever was produced, except perhaps in one
instance.

Sixty-three leaves were immersed in solutions of various strengths;
other leaves being immersed at the same time in the same pure water
used in making the solutions. The results are so remarkable, though
less so than with phosphate of ammonia, that I must describe the
experiments in detail, but I will give only a few. In speaking of the
successive periods when inflection occurred, I always reckon from the
time of first immersion.  [page 150]

Having made some preliminary trials as a guide, five leaves were placed
in the same little vessel in thirty minims of a solution of one part of
the nitrate to 7875 of water (1 gr. to 18 oz.); and this amount of
fluid just sufficed to cover them. After 2 hrs. 10 m. three of the
leaves were considerably inflected, and the other two moderately. The
glands of all became of so dark a red as almost to deserve to be called
black. After 8 hrs. four of the leaves had all their tentacles more or
less inflected; whilst the fifth, which I then perceived to be an old
leaf, had only thirty tentacles inflected. Next morning, after 23 hrs.
40 m., all the leaves were in the same state, excepting that the old
leaf had a few more tentacles inflected. Five leaves which had been
placed at the same time in water were observed at the same intervals of
time; after 2 hrs. 10 m. two of them had four, one had seven, one had
ten, of the long-headed marginal tentacles, and the fifth had four
round-headed tentacles, inflected. After 8 hrs. there was no change in
these leaves, and after 24 hrs. all the marginal tentacles had
re-expanded; but in one leaf, a dozen, and in a second leaf, half a
dozen, submarginal tentacles had become inflected. As the glands of the
five leaves in the solution were simultaneously darkened, no doubt they
had all absorbed a nearly equal amount of the salt: and as 1/288 of a
grain was given to the five leaves together, each got 1/1440 of a grain
(.045 mg.). I did not count the tentacles on these leaves, which were
moderately fine ones, but as the average number on thirty-one leaves
was 192, it would be safe to assume that each bore on an average at
least 160. If so, each of the darkened glands could have received only
1/230400 of a grain of the nitrate; and this caused the inflection of a
great majority of the tentacles.

This plan of immersing several leaves in the same vessel is a bad one,
as it is impossible to feel sure that the more vigorous leaves do not
rob the weaker ones of their share of the salt.  The glands, moreover,
must often touch one another or the sides of the vessel, and movement
may have been thus excited; but the corresponding leaves in water,
which were little inflected, though rather more so than commonly
occurs, were exposed in an almost equal degree to these same sources of
error. I will, therefore, give only one other experiment made in this
manner, though many were tried and all confirmed the foregoing and
following results. Four leaves were placed in forty minims of a
solution of one part to 10,500 of water; and assuming that they
absorbed equally, each leaf received 1/1152 of a grain (.0562 mg.).
After 1 hr. 20 m. many of the tentacles on all four leaves were
somewhat inflected. After [page 151] 5 hrs. 30 m. two leaves had all
their tentacles inflected; a third leaf all except the extreme
marginals, which seemed old and torpid; and the fourth a large number.
After 21 hrs. every single tentacle, on all four leaves, was closely
inflected. Of the four leaves placed at the same time in water, one
had, after 5 hrs. 45 m., five marginal tentacles inflected; a second,
ten; a third, nine marginals and submarginals; and the fourth, twelve,
chiefly submarginals, inflected. After 21 hrs. all these marginal
tentacles re-expanded, but a few of the submarginals on two of the
leaves remained slightly curved inwards. The contrast was wonderfully
great between these four leaves in water and those in the solution, the
latter having every one of their tentacles closely inflected. Making
the moderate assumption that each of these leaves bore 160 tentacles,
each gland could have absorbed only 1/184320 of a grain (.000351 mg.).
This experiment was repeated on three leaves with the same relative
amount of the solution; and after 6 hrs. 15 m. all the tentacles except
nine, on all three leaves taken together, were closely inflected. In
this case the tentacles on each leaf were counted, and gave an average
of 162 per leaf.

The following experiments were tried during the summer of 1873, by
placing the leaves, each in a separate watch-glass and pouring over it
thirty minims (1.775 ml.) of the solution; other leaves being treated
in exactly the same manner with the doubly distilled water used in
making the solutions. The trials above given were made several years
before, and when I read over my notes, I could not believe in the
results; so I resolved to begin again with moderately strong solutions.
Six leaves were first immersed, each in thirty minims of a solution of
one part of the nitrate to 8750 of water (1 gr. to 20 oz.), so that
each received 1/320 of a grain (.2025 mg.). Before 30 m. had elapsed,
four of these leaves were immensely, and two of them moderately,
inflected. The glands were rendered of a dark red. The four
corresponding leaves in water were not at all affected until 6 hrs. had
elapsed, and then only the short tentacles on the borders of the disc;
and their inflection, as previously explained, is never of any
significance.

Four leaves were immersed, each in thirty minims of a solution of one
part to 17,500 of water (1 gr. to 40 oz.), so that each received 1/640
of a grain (.101 mg.); and in less than 45 m.  three of them had all
their tentacles, except from four to ten, inflected; the blade of one
being inflected after 6 hrs., and the blade of a second after 21 hrs.
The fourth leaf was not at all affected. The glands of none were
darkened. Of the corresponding leaves [page 152] in water, only one had
any of its exterior tentacles, namely five, inflected; after 6 hrs. in
one case, and after 21 hrs. in two other cases, the short tentacles on
the borders of the disc formed a ring, in the usual manner.

Four leaves were immersed, each in thirty minims of a solution of one
part to 43,750 of water (1 gr. to 100 oz.), so that each leaf got
1/1600 of a grain (.0405 mg.). Of these, one was much inflected in 8
m., and after 2 hrs. 7 m. had all the tentacles, except thirteen,
inflected. The second leaf, after 10 m., had all except three
inflected. The third and fourth were hardly at all affected, scarcely
more than the corresponding leaves in water. Of the latter, only one
was affected, this having two tentacles inflected, with those on the
outer parts of the disc forming a ring in the usual manner. In the leaf
which had all its tentacles except three inflected in 10 m., each gland
(assuming that the leaf bore 160 tentacles) could have absorbed only
1/251200 of a grain, or .000258 mg.

Four leaves were separately immersed as before in a solution of one
part to 131,250 of water (1 gr. to 300 oz.), so that each received
1/4800 of a grain, or .0135 mg. After 50 m. one leaf had all its
tentacles except sixteen, and after 8 hrs. 20 m. all but fourteen,
inflected. The second leaf, after 40 m., had all but twenty inflected;
and after 8 hrs. 10 m. began to re-expand. The third, in 3 hrs. had
about half its tentacles inflected, which began to re-expand after 8
hrs. 15 m. The fourth leaf, after 3 hrs. 7 m., had only twenty-nine
tentacles more or less inflected. Thus three out of the four leaves
were strongly acted on. It is clear that very sensitive leaves had been
accidentally selected. The day moreover was hot. The four corresponding
leaves in water were likewise acted on rather more than is usual; for
after 3 hrs. one had nine tentacles, another four, and another two, and
the fourth none, inflected.  With respect to the leaf of which all the
tentacles, except sixteen, were inflected after 50 m., each gland
(assuming that the leaf bore 160 tentacles) could have absorbed only
1/691200 of a grain (.0000937 mg.), and this appears to be about the
least quantity of the nitrate which suffices to induce the inflection
of a single tentacle.

As negative results are important in confirming the foregoing positive
ones, eight leaves were immersed as before, each in thirty minims of a
solution of one part to 175,000 of water (1 gr.  to 400 oz.), so that
each received only 1/6400 of a grain (.0101 mg.). This minute quantity
produced a slight effect on only four of the eight leaves. One had
fifty-six tentacles inflected after 2 hrs. 13 m.; a second, twenty-six
inflected, or sub-inflected, after [page 153] 38 m.; a third, eighteen
inflected, after 1 hr.; and a fourth, ten inflected, after 35 m. The
four other leaves were not in the least affected. Of the eight
corresponding leaves in water, one had, after 2 hrs. 10 m., nine
tentacles, and four others from one to four long-headed tentacles,
inflected; the remaining three being unaffected. Hence, the 1/6400 of a
grain given to a sensitive leaf during warm weather perhaps produces a
slight effect; but we must bear in mind that occasionally water causes
as great an amount of inflection as occurred in this last experiment.]

Summary of the Results with Nitrate of Ammonia.--The glands of the
disc, when excited by a half-minim drop (.0296 ml.), containing 1/2400
of a grain of the nitrate (.027 mg.), transmit a motor impulse to the
exterior tentacles, causing them to bend inwards. A minute drop,
containing 1/28800 of a grain (.00225 mg.), if held for a few seconds
in contact with a gland, causes the tentacle bearing this gland to be
inflected. If a leaf is left immersed for a few hours, and sometimes
for only a few minutes, in a solution of such strength that each gland
can absorb only the (1/691200 of a grain (.0000937 mg.), this small
amount is enough to excite each tentacle into movement, and it becomes
closely inflected.

                     PHOSPHATE OF AMMONIA.

This salt is more powerful than the nitrate, even in a greater degree
than the nitrate is more powerful than the carbonate. This is shown by
weaker solutions of the phosphate acting when dropped on the discs, or
applied to the glands of the exterior tentacles, or when leaves are
immersed. The difference in the power of these three salts, as tried in
three different ways, supports the results presently to be [page 154]
given, which are so surprising that their credibility requires every
kind of support. In 1872 I experimented on twelve immersed leaves,
giving each only ten minims of a solution; but this was a bad method,
for so small a quantity hardly covered them. None of these experiments
will, therefore, be given, though they indicate that excessively minute
doses are efficient.  When I read over my notes, in 1873, I entirely
disbelieved them, and determined to make another set of experiments
with scrupulous care, on the same plan as those made with the nitrate;
namely by placing leaves in watch-glasses, and pouring over each thirty
minims of the solution under trial, treating at the same time and in
the same manner other leaves with the distilled water used in making
the solutions. During 1873, seventy-one leaves were thus tried in
solutions of various strengths, and the same number in water.
Notwithstanding the care taken and the number of the trials made, when
in the following year I looked merely at the results, without reading
over my observations, I again thought that there must have been some
error, and thirty-five fresh trials were made with the weakest
solution; but the results were as plainly marked as before. Altogether,
106 carefully selected leaves were tried, both in water and in
solutions of the phosphate. Hence, after the most anxious
consideration, I can entertain no doubt of the substantial accuracy of
my results.

[Before giving my experiments, it may be well to premise that
crystallised phosphate of ammonia, such as I used, contains 35.33 per
cent. of water of crystallisation; so that in all the following trials
the efficient elements formed only 64.67 per cent. of the salt used.

Extremely minute particles of the dry phosphate were placed [page 155]
with the point of a needle on the secretion surrounding several glands.
These poured forth much secretion, were blackened, and ultimately died;
but the tentacles moved only slightly.  The dose, small as it was,
evidently was too great, and the result was the same as with particles
of the carbonate of ammonia.

Half-minims of a solution of one part to 437 of water were placed on
the discs of three leaves and acted most energetically, causing the
tentacles of one to be inflected in 15 m., and the blades of all three
to be much curved inwards in 2 hrs. 15 m. Similar drops of a solution
of one part to 1312 of water, (1 gr. to 3 oz.) were then placed on the
discs of five leaves, so that each received the 1/2880 of a grain
(.0225 mg.). After 8 hrs. the tentacles of four of them were
considerably inflected, and after 24 hrs. the blades of three. After 48
hrs. all five were almost fully re-expanded. I may mention with respect
to one of these leaves, that a drop of water had been left during the
previous 24 hrs. on its disc, but produced no effect; and that this was
hardly dry when the solution was added.

Similar drops of a solution of one part to 1750 of water (1 gr. to 4
oz.) were next placed on the discs of six leaves; so that each received
1/3840 of a grain (.0169 mg.); after 8 hrs. three of them had many
tentacles and their blades inflected; two others had only a few
tentacles slightly inflected, and the sixth was not at all affected.
After 24 hrs. most of the leaves had a few more tentacles inflected,
but one had begun to re-expand. We thus see that with the more
sensitive leaves the 1/3840 of a grain, absorbed by the central glands,
is enough to make many of the exterior tentacles and the blades bend,
whereas the 1/1920 of a grain of the carbonate similarly given produced
no effect; and 1/2880 of a grain of the nitrate was only just
sufficient to produce a well-marked effect.

A minute drop, about equal to 1/20 of a minim, of a solution of one
part of the phosphate to 875 of water, was applied to the secretion on
three glands, each of which thus received only 1/57600 of a grain
(.00112 mg.), and all three tentacles became inflected. Similar drops
of a solution of one part to 1312 of water (1 gr. to 3 oz.) were now
tried on three leaves; a drop being applied to four glands on the same
leaf. On the first leaf, three of the tentacles became slightly
inflected in 6 m., and re-expanded after 8 hrs. 45 m. On the second,
two tentacles became sub-inflected in 12 m. And on the third all four
tentacles were decidedly inflected in 12 m.; they remained so for 8
hrs. 30 m., but by the next morning were fully re-expanded.  [page 156]
In this latter case each gland could have received only the 1/115200
(or .000563 mg.) of a grain. Lastly, similar drops of a solution of one
part to 1750 of water (1 gr. to 4 oz.) were tried on five leaves; a
drop being applied to four glands on the same leaf. The tentacles on
three of these leaves were not in the least affected; on the fourth
leaf, two became inflected; whilst on the fifth, which happened to be a
very sensitive one, all four tentacles were plainly inflected in 6 hrs.
15m.; but only one remained inflected after 24 hrs. I should, however,
state that in this case an unusually large drop adhered to the head of
the pin. Each of these glands could have received very little more than
1/153600 of a grain (or .000423); but this small quantity sufficed to
cause inflection. We must bear in mind that these drops were applied to
the viscid secretion for only from 10 to 15 seconds, and we have good
reason to believe that all the phosphate in the solution would not be
diffused and absorbed in this time. We have seen under the same
circumstances that the absorption by a gland of 1/19200 of a grain of
the carbonate, and of 1/57600 of a grain of the nitrate, did not cause
the tentacle bearing the gland in question to be inflected; so that
here again the phosphate is much more powerful than the other two
salts.

We will now turn to the 106 experiments with immersed leaves. Having
ascertained by repeated trials that moderately strong solutions were
highly efficient, I commenced with sixteen leaves, each placed in
thirty minims of a solution of one part to 43,750 of water (1 gr.  to
100 oz.); so that each received 1/1600 of a grain, or .04058 mg. Of
these leaves, eleven had nearly all or a great number of their
tentacles inflected in 1 hr., and the twelfth leaf in 3 hrs. One of the
eleven had every single tentacle closely inflected in 50 m. Two leaves
out of the sixteen were only moderately affected, yet more so than any
of those simultaneously immersed in water; and the remaining two, which
were pale leaves, were hardly at all affected. Of the sixteen
corresponding leaves in water, one had nine tentacles, another six, and
two others two tentacles inflected, in the course of 5 hrs. So that the
contrast in appearance between the two lots was extremely great.

Eighteen leaves were immersed, each in thirty minims of a solution of
one part to 87,500 of water (1 gr. to 200 oz.), so that each received
1/3200 of a grain (.0202 mg.). Fourteen of these were strongly
inflected within 2 hrs., and some of them within 15 m.; three out of
the eighteen were only slightly affected, having twenty-one, nineteen,
and twelve tentacles in- [page 157] flected; and one was not at all
acted on. By an accident only fifteen, instead of eighteen, leaves were
immersed at the same time in water; these were observed for 24 hrs.;
one had six, another four, and a third two, of their outer tentacles
inflected; the remainder being quite unaffected.

The next experiment was tried under very favourable circumstances, for
the day (July 8) was very warm, and I happened to have unusually fine
leaves. Five were immersed as before in a solution of one part to
131,250 of water (1 gr. to 300 oz.), so that each received 1/4800 of a
grain, or .0135 mg. After an immersion of 25 m. all five leaves were
much inflected. After 1 hr. 25 m. one leaf had all but eight tentacles
inflected; the second, all but three; the third, all but five; the
fourth; all but twenty-three; the fifth, on the other hand, never had
more than twenty-four inflected. Of the corresponding five leaves in
water, one had seven, a second two, a third ten, a fourth one, and a
fifth none inflected. Let it be observed what a contrast is presented
between these latter leaves and those in the solution. I counted the
glands on the second leaf in the solution, and the number was 217;
assuming that the three tentacles which did not become inflected
absorbed nothing, we find that each of the 214 remaining glands could
have absorbed only 1/l027200 of a grain, or .0000631 mg. The third leaf
bore 236 glands, and subtracting the five which did not become
inflected, each of the remaining 231 glands could have absorbed only
1/1108800 of a grain (or .0000584 mg.), and this amount sufficed to
cause the tentacles to bend.

Twelve leaves were tried as before in a solution of one part to 175,000
of water (1 gr. to 400 oz.), so that each leaf received 1/6400 of a
grain (.0101 mg.). My plants were not at the time in a good state, and
many of the leaves were young and pale. Nevertheless, two of them had
all their tentacles, except three or four, closely inflected in under 1
hr. Seven were considerably affected, some within 1 hr., and others not
until 3 hrs., 4 hrs. 30 m., and 8 hrs.  had elapsed; and this slow
action may be attributed to the leaves being young and pale. Of these
nine leaves, four had their blades well inflected, and a fifth slightly
so. The three remaining leaves were not affected. With respect to the
twelve corresponding leaves in water, not one had its blade inflected;
after from 1 to 2 hrs. one had thirteen of its outer tentacles
inflected; a second six, and four others either one or two inflected.
After 8 hrs. the outer tentacles did not become more inflected; whereas
this occurred with the leaves in the solution. I record in my notes
that [page 158] after the 8 hrs. it was impossible to compare the two
lots, and doubt for an instant the power of the solution.

Two of the above leaves in the solution had all their tentacles, except
three and four, inflected within an hour. I counted their glands, and,
on the same principle as before, each gland on one leaf could have
absorbed only 1/1164800, and on the other leaf only 1/1472000, of a
grain of the phosphate.

Twenty leaves were immersed in the usual manner, each in thirty minims
of a solution of one part to 218,750 of water (1 gr. to 500 oz.). So
many leaves were tried because I was then under the false impression
that it was incredible that any weaker solution could produce an
effect. Each leaf received 1/8000 of a grain, or .0081 mg. The first
eight leaves which I tried both in the solution and in water were
either young and pale or too old; and the weather was not hot. They
were hardly at all affected; nevertheless, it would be unfair to
exclude them. I then waited until I got eight pairs of fine leaves, and
the weather was favourable; the temperature of the room where the
leaves were immersed varying from 75o to 81o (23o.8 to 27o.2 Cent.) In
another trial with four pairs (included in the above twenty pairs), the
temperature in my room was rather low, about 60o (15o.5 Cent.); but the
plants had been kept for several days in a very warm greenhouse and
thus rendered extremely sensitive. Special precautions were taken for
this set of experiments; a chemist weighed for me a grain in an
excellent balance; and fresh water, given me by Prof. Frankland, was
carefully measured.  The leaves were selected from a large number of
plants in the following manner: the four finest were immersed in water,
and the next four finest in the solution, and so on till the twenty
pairs were complete. The water specimens were thus a little favoured,
but they did not undergo more inflection than in the previous cases,
comparatively with those in the solution.

Of the twenty leaves in the solution, eleven became inflected within 40
m.; eight of them plainly and three rather doubtfully; but the latter
had at least twenty of their outer tentacles inflected. Owing to the
weakness of the solution, inflection occurred, except in No. 1, much
more slowly than in the previous trials. The condition of the eleven
leaves which were considerably inflected will now be given at stated
intervals, always reckoning from the time of immersion:--

(1) After only 8 m. a large number of tentacles inflected, and after 17
m. all but fifteen; after 2 hrs. all but eight in- [page 159] flected,
or plainly sub-inflected. After 4 hrs. the tentacles began to
re-expand, and such prompt re-expansion is unusual; after 7 hrs. 30 m.
they were almost fully re-expanded.

(2) After 39 m. a large number of tentacles inflected; after 2 hrs. 18
m. all but twenty-five inflected; after 4 hrs. 17 m. all but sixteen
inflected. The leaf remained in this state for many hours.

(3) After 12 m. a considerable amount of inflection; after 4 hrs. all
the tentacles inflected except those of the two outer rows, and the
leaf remained in this state for some time; after 23 hrs. began to
re-expand.

(4) After 40 m. much inflection; after 4 hrs. 13 m. fully half the
tentacles inflected; after 23 hrs. still slightly inflected.

(5) After 40 m. much inflection; after 4 hrs. 22 m. fully half the
tentacles inflected; after 23 hrs. still slightly inflected.

(6) After 40 m. some inflection; after 2 hrs. 18 m. about twenty-eight
outer tentacles inflected; after 5 hrs. 20 m. about a third of the
tentacles inflected; after 8 hrs. much re-expanded.

(7) After 20 m. some inflection; after 2 hrs. a considerable number of
tentacles inflected; after 7 hrs. 45 m. began to re-expand.

(8) After 38 m. twenty-eight tentacles inflected; after 3 hrs. 45 m.
thirty-three inflected, with most of the submarginal tentacles
sub-inflected; continued so for two days, and then partially
re-expanded.

(9) After 38 m. forty-two tentacles inflected; after 3 hrs. 12 m.
sixty-six inflected or sub-inflected; after 6 hrs. 40 m. all but
twenty-four inflected or sub-inflected; after 9 hrs. 40 m. all but
seventeen inflected; after 24 hrs. all but four inflected or
sub-inflected, only a few being closely inflected; after 27 hrs. 40 m.
the blade inflected. The leaf remained in this state for two days, and
then began to re-expand.

(10) After 38 m. twenty-one tentacles inflected; after 3 hrs. 12 m.
forty-six tentacles inflected or sub-inflected; after 6 hrs. 40 m. all
but seventeen inflected, though none closely; after 24 hrs. every
tentacle slightly curved inwards; after 27 hrs. 40 m. blade strongly
inflected, and so continued for two days, and then the tentacles and
blade very slowly re-expanded.

(11) This fine dark red and rather old leaf, though not very large,
bore an extraordinary number of tentacles (viz. 252), and behaved in an
anomalous manner. After 6 hrs. 40 m. only the short tentacles round the
outer part of the disc were inflected, forming a ring, as so often
occurs in from 8 to 24 hrs. With leaves both in water and the weaker
solutions. But after 9 hrs.  [page 160] 40 m. all the outer tentacles
except twenty-five were inflected; as was the blade in a strongly
marked manner. After 24 hrs. every tentacle except one was closely
inflected, and the blade was completely doubled over. Thus the leaf
remained for two days, when it began to re-expand. I may add that the
three latter leaves (Nos. 9, 10, and 11) were still somewhat inflected
after three days. The tentacles in but few of these eleven leaves
became closelyinflected within so short a time as in the previous
experiments with stronger solutions.

We will now turn to the twenty corresponding leaves in water. Nine had
none of their outer tentacles inflected; nine others had from one to
three inflected; and these re-expanded after 8 hrs. The remaining two
leaves were moderately affected; one having six tentacles inflected in
34 m.; the other twenty-three inflected in 2 hrs. 12 m.; and both thus
remained for 24 hrs.  None of these leaves had their blades inflected.
So that the contrast between the twenty leaves in water and the twenty
in the solution was very great, both within the first hour and after
from 8 to 12 hrs. had elapsed.

Of the leaves in the solution, the glands on leaf No. 1, which in 2
hrs. had all its tentacles except eight inflected, were counted and
found to be 202. Subtracting the eight, each gland could have received
only the 1/1552000 grain (.0000411 mg.) of the phosphate. Leaf No. 9
had 213 tentacles, all of which, with the exception of four, were
inflected after 24 hrs., but none of them closely; the blade was also
inflected; each gland could have received only the 1/1672000 of a
grain, or .0000387 mg. Lastly, leaf No. 11, which had after 24 hrs. all
its tentacles, except one, closely inflected, as well as the blade,
bore the unusually large number of 252 tentacles; and on the same
principle as before, each gland could have absorbed only the 1/2008000
of a grain, or .0000322 mg.

With respect to the following experiments, I must premise that the
leaves, both those placed in the solutions and in water, were taken
from plants which had been kept in a very warm greenhouse during the
winter. They were thus rendered extremely sensitive, as was shown by
water exciting them much more than in the previous experiments. Before
giving my observations, it may be well to remind the reader that,
judging from thirty-one fine leaves, the average number of tentacles is
192, and that the outer or exterior ones, the movements of which are
alone significant, are to the short ones on the disc in the proportion
of about sixteen to nine.  [page 161]

Four leaves were immersed as before, each in thirty minims of a
solution of one part to 328,125 of water (1 gr. to 750 oz.). Each leaf
thus received 1/12000 of a grain (.0054 mg.) of the salt; and all four
were greatly inflected.

(1) After 1 hr. all the outer tentacles but one inflected, and the
blade greatly so; after 7 hrs.  began to re-expand.

(2) After 1 hr. all the outer tentacles but eight inflected; after 12
hrs. all re-expanded.

(3) After 1 hr. much inflection; after 2 hrs. 30 m. all the tentacles
but thirty-six inflected; after 6 hrs. all but twenty-two inflected;
after 12 hrs. partly re-expanded.

(4) After 1 hr. all the tentacles but thirty-two inflected; after 2
hrs. 30 m. all but twenty-one inflected; after 6 hrs. almost
re-expanded.

Of the four corresponding leaves in water:--

(1) After 1 hr. forty-five tentacles inflected; but after 7 hrs. so
many had re-expanded that only ten remained much inflected.

(2) After 1 hr. seven tentacles inflected; these were almost
re-expanded in 6 hrs.

(3) and (4) Not affected, except that, as usual, after 11 hrs. the
short tentacles on the borders of the disc formed a ring.

There can, therefore, be no doubt about the efficiency of the above
solution; and it follows as before that each gland of No. 1 could have
absorbed only 1/2412000 of a grain (.0000268 mg.) and of No. 2 only
1/2460000 of a grain (.0000263 mg.) of the phosphate.

Seven leaves were immersed, each in thirty minims of a solution of one
part to 437,500 of water (1 gr. to 1000 oz.). Each leaf thus received
1/16000 of a grain (.00405 mg.). The day was warm, and the leaves were
very fine, so that all circumstances were favourable.

(1) After 30 m. all the outer tentacles except five inflected, and most
of them closely; after 1 hr. blade slightly inflected; after 9 hrs. 30
m. began to re-expand.

(2) After 33 m. all the outer tentacles but twenty-five inflected, and
blade slightly so; after 1 hr. 30 m. blade strongly inflected and
remained so for 24 hrs.; but some of the tentacles had then
re-expanded.

(3) After 1 hr. all but twelve tentacles inflected; after 2 hrs. 30 m.
all but nine inflected; and of the inflected tentacles all excepting
four closely; blade slightly inflected. After 8 hrs. blade quite
doubled up, and now all the tentacles excepting [page 162] eight
closely inflected. The leaf remained in this state for two days.

(4) After 2 hrs. 20 m. only fifty-nine tentacles inflected; but after 5
hrs. all the tentacles closely inflected excepting two which were not
affected, and eleven which were only sub-inflected; after 7 hrs. blade
considerably inflected; after 12 hrs. much re-expansion.

(5) After 4 hrs. all the tentacles but fourteen inflected; after 9 hrs.
30 m. beginning to re-expand.

(6) After 1 hr. thirty-six tentacles inflected; after 5 hrs. all but
fifty-four inflected; after 12 hrs. considerable re-expansion.

(7) After 4 hrs. 30 m. only thirty-five tentacles inflected or
sub-inflected, and this small amount of inflection never increased.

Now for the seven corresponding leaves in water:--

(1) After 4 hrs. thirty-eight tentacles inflected; but after 7 hrs.
these, with the exception of six, re-expanded.

(2) After 4 hrs. 20 m. twenty inflected; these after 9 hrs. partially
re-expanded.

(3) After 4 hrs. five inflected, which began to re-expand after 7 hrs.

(4) After 24 hrs. one inflected.

(5), (6) and (7) Not at all affected, though observed for 24 hrs.,
excepting the short tentacles on the borders of the disc, which as
usual formed a ring.

A comparison of the leaves in the solution, especially of the first
five or even six on the list, with those in the water, after 1 hr. or
after 4 hrs., and in a still more marked degree after 7 hrs. or 8 hrs.,
could not leave the least doubt that the solution had produced a great
effect.  This was shown not only by the vastly greater number of
inflected tentacles, but by the degree or closeness of their
inflection, and by that of their blades. Yet each gland on leaf No.  1
(which bore 255 glands, all of which, excepting five, were inflected in
30 m.) could not have received more than one-four-millionth of a grain
(.0000162 mg.) of the salt. Again, each gland on leaf No. 3 (which bore
233 glands, all of which, except nine, were inflected in 2 hrs.  30 m.)
could have received at most only the 1/3584000 of a grain, or .0000181
mg.

Four leaves were immersed as before in a solution of one part to
656,250 of water (1 gr. to 1500 oz.); but on this occasion I happened
to select leaves which were very little sensitive, as on other
occasions I chanced to select unusually sensitive leaves. The leaves
were not more affected after 12 hrs. than [page 163] the four
corresponding ones in water; but after 24 hrs. they were slightly more
inflected.  Such evidence, however, is not at all trustworthy.

Twelve leaves were immersed, each in thirty minims of a solution of one
part to 1,312,500 of water (1 gr. to 3000 oz.); so that each leaf
received 1/48000 of a grain (.00135 mg.). The leaves were not in very
good condition; four of them were too old and of a dark red colour;
four were too pale, yet one of these latter acted well; the four
others, as far as could be told by the eye, seemed in excellent
condition. The result was as follows:--

(1) This was a pale leaf; after 40 m. about thirty-eight tentacles
inflected; after 3 hrs. 30 m.  the blade and many of the outer
tentacles inflected; after 10 hrs. 15 m. all the tentacles but
seventeen inflected, and the blade quite doubled up; after 24 hrs. all
the tentacles but ten more or less inflected. Most of them were closely
inflected, but twenty-five were only sub-inflected.

(2) After 1 hr. 40 m. twenty-five tentacles inflected; after 6 hrs. all
but twenty-one inflected; after 10 hrs. all but sixteen more or less
inflected; after 24 hrs. re-expanded.

(3) After 1 hr. 40 m. thirty-five inflected; after 6 hrs. "a large
number" (to quote my own memorandum) inflected, but from want of time
they were not counted; after 24 hrs.  re-expanded.

(4) After 1 hr. 40 m. about thirty inflected; after 6 hrs. "a large
number all round the leaf" inflected, but they were not counted; after
10 hrs. began to re-expand.

(5) to (12) These were not more inflected than leaves often are in
water, having respectively 16, 8, 10, 8, 4, 9, 14, and 0 tentacles
inflected. Two of these leaves, however, were remarkable from having
their blades slightly inflected after 6 hrs.

With respect to the twelve corresponding leaves in water, (1) had,
after 1 hr. 35 m., fifty tentacles inflected, but after 11 hrs. only
twenty-two remained so, and these formed a group, with the blade at
this point slightly inflected. It appeared as if this leaf had been in
some manner accidentally excited, for instance by a particle of animal
matter which was dissolved by the water. (2) After 1 hr. 45 m.
thirty-two tentacles inflected, but after 5 hrs. 30 m. only twenty-five
inflected, and these after 10 hrs. all re-expanded; (3) after 1 hr.
twenty-five inflected, which after 10 hrs. 20 m. were all re-expanded;
(4) and (5) after 1 hr. 35 m. six and seven tentacles inflected, which
re-expanded after 11 hrs.; (6), (7) and (8) from one to three
inflected, which [page 164] soon re-expanded; (9), (10), (11) and (12)
none inflected, though observed for twenty-four hours.

Comparing the states of the twelve leaves in water with those in the
solution, there could be no doubt that in the latter a larger number of
tentacles were inflected, and these to a greater degree; but the
evidence was by no means so clear as in the former experiments with
stronger solutions. It deserves attention that the inflection of four
of the leaves in the solution went on increasing during the first 6
hrs., and with some of them for a longer time; whereas in the water the
inflection of the three leaves which were the most affected, as well as
of all the others, began to decrease during this same interval. It is
also remarkable that the blades of three of the leaves in the solution
were slightly inflected, and this is a most rare event with leaves in
water, though it occurred to a slight extent in one (No. 1), which
seemed to have been in some manner accidentally excited. All this shows
that the solution produced some effect, though less and at a much
slower rate than in the previous cases. The small effect produced may,
however, be accounted for in large part by the majority of the leaves
having been in a poor condition.

Of the leaves in the solution, No. 1 bore 200 glands and received
1/48000 of a grain of the salt. Subtracting the seventeen tentacles
which were not inflected, each gland could have absorbed only the
1/8784000 of a grain (.00000738 mg.). This amount caused the tentacle
bearing each gland to be greatly inflected. The blade was also
inflected.

Lastly, eight leaves were immersed, each in thirty minims of a solution
of one part of the phosphate to 21,875,000 of water (1 gr. to 5000
oz.). Each leaf thus received 1/80000 of a grain of the salt, or .00081
mg. I took especial pains in selecting the finest leaves from the
hot-house for immersion, both in the solution and the water, and almost
all proved extremely sensitive. Beginning as before with those in the
solution:--

(1) After 2 hrs. 30 m. all the tentacles but twenty-two inflected, but
some only sub-inflected; the blade much inflected; after 6 hrs. 30 m.
all but thirteen inflected, with the blade immensely inflected; and
remained so for 48 hrs.

(2) No change for the first 12 hrs., but after 24 hrs. all the
tentacles inflected, excepting those of the outermost row, of which
only eleven were inflected. The inflection continued to increase, and
after 48 hrs. all the tentacles except three were inflected, [page 165]
and most of them rather closely, four or five being only
sub-inflected.

(3) No change for the first 12 hrs.; but after 24 hrs. all the
tentacles excepting those of the outermost row were sub-inflected, with
the blade inflected. After 36 hrs. blade strongly inflected, with all
the tentacles, except three, inflected or sub-inflected. After 48 hrs.
in the same state.

(4) to (8) These leaves, after 2 hrs. 30 m., had respectively 32, 17,
7, 4, and 0 tentacles inflected, most of which, after a few hours,
re-expanded, with the exception of No. 4, which retained its thirty-two
tentacles inflected for 48 hrs.

Now for the eight corresponding leaves in water:--

(1) After 2 hrs. 40 m. this had twenty of its outer tentacles
inflected, five of which re-expanded after 6 hrs. 30 m. After 10 hrs.
15 m. a most unusual circumstance occurred, namely, the whole blade
became slightly bowed towards the footstalk, and so remained for 48
hrs. The exterior tentacles, excepting those of the three or four
outermost rows, were now also inflected to an unusual degree.

(2) to (8) These leaves, after 2 hrs. 40 m., had respectively 42, 12,
9, 8, 2, 1, and 0 tentacles inflected, which all re-expanded within 24
hrs., and most of them within a much shorter time.

When the two lots of eight leaves in the solution and in the water were
compared after the lapse of 24 hrs., they undoubtedly differed much in
appearance. The few tentacles on the leaves in water which were
inflected had after this interval re-expanded, with the exception of
one leaf; and this presented the very unusual case of the blade being
somewhat inflected, though in a degree hardly approaching that of the
two leaves in the solution. Of these latter leaves, No. 1 had almost
all its tentacles, together with its blade, inflected after an
immersion of 2 hrs. 30 m. Leaves No. 2 and 3 were affected at a much
slower rate; but after from 24 hrs.  to 48 hrs. almost all their
tentacles were closely inflected, and the blade of one quite doubled
up. We must therefore admit, incredible as the fact may at first
appear, that this extremely weak solution acted on the more sensitive
leaves; each of which received only the 1/80000 of a grain (.00081 mg.)
of the phosphate. Now, leaf No. 3 bore 178 tentacles, and subtracting
the three which were not inflected, each gland could have absorbed only
the 1/14000000 of a grain, or .00000463 mg. Leaf No. 1, which was
strongly acted on within 2 hrs. 30 m., and had all its outer tentacles,
except thirteen, inflected within 6 hrs. 30 m., bore 260 tentacles; and
on the same principle as before, each gland could have [page 166]
absorbed only 1/19760000 of a grain, or .00000328 mg.; and this
excessively minute amount sufficed to cause all the tentacles bearing
these glands to be greatly inflected. The blade was also inflected.]

Summary of the Results with Phosphate of Ammonia.--The glands of the
disc, when excited by a half-minim drop (.0296 ml.), containing 1/3840
of a grain (.0169 mg.) of this salt, transmit a motor impulse to the
exterior tentacles, causing them to bend inwards. A minute drop,
containing 1/153600 of a grain (.000423 mg.), if held for a few seconds
in contact with a gland, causes the tentacle bearing this gland to be
inflected. If a leaf is left immersed for a few hours, and sometimes
for a shorter time, in a solution so weak that each gland can absorb
only the 1/9760000 of a grain (.00000328 mg.), this is enough to excite
the tentacle into movement, so that it becomes closely inflected, as
does sometimes the blade. In the general summary to this chapter a few
remarks will be added, showing that the efficiency of such extremely
minute doses is not so incredible as it must at first appear.

[Sulphate of Ammonia.--The few trials made with this and the following
five salts of ammonia were undertaken merely to ascertain whether they
induced inflection. Half-minims of a solution of one part of the
sulphate of ammonia to 437 of water were placed on the discs of seven
leaves, so that each received 1/960 of a grain, or .0675 mg. After 1
hr. the tentacles of five of them, as well as the blade of one, were
strongly inflected. The leaves were not afterwards observed.

Citrate of Ammonia.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves. In 1 hr. the short outer
tentacles round the discs were a little inflected, with the glands on
the discs blackened. After 3 hrs. 25 m. one leaf had its blade
inflected, but none of the exterior tentacles. All six leaves remained
in nearly the same state during the day, the submarginal tentacles,
however, [page 167] becoming more inflected. After 23 hrs. three of the
leaves had their blades somewhat inflected; and the submarginal
tentacles of all considerably inflected, but in none were the two,
three, or four outer rows affected. I have rarely seen cases like this,
except from the action of a decoction of grass. The glands on the discs
of the above leaves, instead of being almost black, as after the first
hour, were now after 23 hrs. very pale. I next tried on four leaves
half-minims of a weaker solution, of one part to 1312 of water (1 gr.
to 3 oz.); so that each received 1/2880 of a grain (.0225 mg.). After 2
hrs. 18 m. the glands on the disc were very dark-coloured; after 24
hrs. two of the leaves were slightly affected; the other two not at
all.

Acetate of Ammonia.--Half-minims of a solution of about one part to 109
of water were placed on the discs of two leaves, both of which were
acted on in 5 hrs. 30 m., and after 23 hrs. had every single tentacle
closely inflected.

Oxalate of Ammonia.--Half-minims of a solution of one part to 218 of
water were placed on two leaves, which, after 7 hrs., became
moderately, and after 23 hrs. strongly, inflected. Two other leaves
were tried with a weaker solution of one part to 437 of water; one was
strongly inflected in 7 hrs.; the other not until 30 hrs. had elapsed.

Tartrate of Ammonia.--Half-minims of a solution of one part to 437 of
water were placed on the discs of five leaves. In 31 m. there was a
trace of inflection in the exterior tentacles of some of the leaves,
and this became more decided after 1 hr. with all the leaves; but the
tentacles were never closely inflected. After 8 hrs. 30 m. they began
to re-expand. Next morning, after 23 hrs., all were fully re-expanded,
excepting one which was still slightly inflected. The shortness of the
period of inflection in this and the following case is remarkable.

Chloride of Ammonium.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves. A decided degree of
inflection in the outer and submarginal tentacles was perceptible in 25
m.; and this increased during the next three or four hours, but never
became strongly marked. After only 8 hrs. 30 m. the tentacles began to
re-expand, and by the next morning, after 24 hrs., were fully
re-expanded on four of the leaves, but still slightly inflected on
two.]

General Summary and Concluding Remarks on the Salts of Ammonia.--We
have now seen that the nine [page 168] salts of ammonia which were
tried, all cause the inflection of the tentacles, and often of the
blade of the leaf. As far as can be ascertained from the superficial
trials with the last six salts, the citrate is the least powerful, and
the phosphate certainly by far the most. The tartrate and chloride are
remarkable from the short duration of their action. The relative
efficiency of the carbonate, nitrate, and phosphate, is shown in the
following table by the smallest amount which suffices to cause the
inflection of the tentacles.

Column 1 : Solutions, how applied.  Column 2 : Carbonate of Ammonia.
Column 3 : Nitrate of Ammonia.  Column 4 : Phosphate of Ammonia.

Placed on the glands of the disc, so as to act indirectly on the outer
tentacles :  1/960 of a grain, or 0675 mg. : 1/2400 of a grain, or .027
mg. : 1/3840 of a grain, or .0169 mg.

Applied for a few seconds directly to the gland of an outer tentacle :
1/14400 of a grain, or .00445 mg. : 1/28800 of a grain, or .0025 mg.
grain, 1/153600 of a grain, or .000423 mg.

Leaf immersed, with time allowed for each gland to absorb all that it
can :  1/268800 of a grain, or .00024 mg. : 1/691200 of a grain, or
.0000937 mg. : 1/19760000 of a grain, or .00000328 mg.

Amount absorbed by a gland which suffices to cause the aggregation of
the protoplasm in the adjoining cells of the tentacles. 1/134400 of a
grain, or .00048 mg.

From the experiments tried in these three different ways, we see that
the carbonate, which contains 23.7 per cent. of nitrogen, is less
efficient than the nitrate, which contains 35 per cent. The phosphate
contains less nitrogen than either of these salts, namely, only 21.2
per cent., and yet is far more [page 169] efficient; its power no doubt
depending quite as much on the phosphorus as on the nitrogen which it
contains. We may infer that this is the case, from the energetic manner
in which bits of bone and phosphate of lime affect the leaves. The
inflection excited by the other salts of ammonia is probably due solely
to their nitrogen,--on the same principle that nitrogenous organic
fluids act powerfully, whilst non-nitrogenous organic fluids are
powerless. As such minute doses of the salts of ammonia affect the
leaves, we may feel almost sure that Drosera absorbs and profits by the
amount, though small, which is present in rain-water, in the same
manner as other plants absorb these same salts by their roots.

The smallness of the doses of the nitrate, and more especially of the
phosphate of ammonia, which cause the tentacles of immersed leaves to
be inflected, is perhaps the most remarkable fact recorded in this
volume. When we see that much less than the millionth* of a grain of
the phosphate, absorbed by a gland of one of the exterior tentacles,
causes it to bend, it may be thought that the effects of the solution
on the glands of the disc have been overlooked; namely, the
transmission of a motor impulse from them to the exterior tentacles. No
doubt the movements of the latter are thus aided; but the aid thus
rendered must be insignificant; for we know that a drop containing as
much as the 1/3840 of a grain placed on the disc is only just able to
cause the outer tentacles of a highly sensitive leaf to bend. It is
cer-

* It is scarcely possible to realise what a million means. The best
illustration which I have met with is that given by Mr. Croll, who
says, "Take a narrow strip of paper 83 ft. 4 in. in length, and stretch
it along the wall of a large hall; then mark off at one end the tenth
of an inch. This tenth will represent a hundred, and the entire strip a
million.  [page 170]

tainly a most surprising fact that the 1/19760000 of a grain, or in
round numbers the one-twenty-millionth of a grain (.0000033 mg.), of
the phosphate should affect any plant, or indeed any animal; and as
this salt contains 35.33 per cent. of water of crystallisation, the
efficient elements are reduced to 1/30555126 of a grain, or in round
numbers to one-thirty-millionth of a grain (.00000216 mg.). The
solution, moreover, in these experiments was diluted in the proportion
of one part of the salt to 2,187,500 of water, or one grain to 5000 oz.
The reader will perhaps best realise this degree of dilution by
remembering that 5000 oz. would more than fill a 31-gallon cask; and
that to this large body of water one grain of the salt was added; only
half a drachm, or thirty minims, of the solution being poured over a
leaf. Yet this amount sufficed to cause the inflection of almost every
tentacle, and often of the blade of the leaf.

I am well aware that this statement will at first appear incredible to
almost everyone. Drosera is far from rivalling the power of the
spectroscope, but it can detect, as shown by the movements of its
leaves, a very much smaller quantity of the phosphate of ammonia than
the most skilful chemist can of any substance.* My results were for a
long time incredible

* When my first observations were made on the nitrate of ammonia,
fourteen years ago, the powers of the spectroscope had not been
discovered; and I felt all the greater interest in the then unrivalled
powers of Drosera. Now the spectroscope has altogether beaten Drosera;
for according to Bunsen and Kirchhoff probably less than one
1/200000000 of a grain of sodium can be thus detected (see Balfour
Stewart, 'Treatise on Heat,' 2nd edit. 1871, p. 228). With respect to
ordinary chemical tests, I gather from Dr. Alfred Taylor's work on
'Poisons' that about 1/4000 of a grain of arsenic, 1/4400 of a grain of
prussic acid, 1/1400 of iodine, and 1/2000 of tartarised antimony, can
be detected; but the power of detection depends much on the solutions
under trial not being extremely weak.  [page 171]

even to myself, and I anxiously sought for every source of error. The
salt was in some cases weighed for me by a chemist in an excellent
balance; and fresh water was measured many times with care. The
observations were repeated during several years. Two of my sons, who
were as incredulous as myself, compared several lots of leaves
simultaneously immersed in the weaker solutions and in water, and
declared that there could be no doubt about the difference in their
appearance. I hope that some one may hereafter be induced to repeat my
experiments; in this case he should select young and vigorous leaves,
with the glands surrounded by abundant secretion. The leaves should be
carefully cut off and laid gently in watch-glasses, and a measured
quantity of the solution and of water poured over each. The water used
must be as absolutely pure as it can be made. It is to be especially
observed that the experiments with the weaker solutions ought to be
tried after several days of very warm weather. Those with the weakest
solutions should be made on plants which have been kept for a
considerable time in a warm greenhouse, or cool hothouse; but this is
by no means necessary for trials with solutions of moderate strength.

I beg the reader to observe that the sensitiveness or irritability of
the tentacles was ascertained by three different methods--indirectly by
drops placed on the disc, directly by drops applied to the glands of
the outer tentacles, and by the immersion of whole leaves; and it was
found by these three methods that the nitrate was more powerful than
the carbonate, and the phosphate much more powerful than the nitrate;
this result being intelligible from the difference in the amount of
nitrogen in the first two salts, and from the presence of phosphorus in
the third. It may aid the [page 172] reader's faith to turn to the
experiments with a solution of one grain of the phosphate to 1000 oz.
of water, and he will there find decisive evidence that the
one-four-millionth of a grain is sufficient to cause the inflection of
a single tentacle. There is, therefore, nothing very improbable in the
fifth of this weight, or the one-twenty-millionth of a grain, acting on
the tentacle of a highly sensitive leaf. Again, two of the leaves in
the solution of one grain to 3000 oz., and three of the leaves in the
solution of one grain to 5000 oz., were affected, not only far more
than the leaves tried at the same time in water, but incomparably more
than any five leaves which can be picked out of the 173 observed by me
at different times in water.

There is nothing remarkable in the mere fact of the
one-twenty-millionth of a grain of the phosphate, dissolved in above
two-million times its weight of water, being absorbed by a gland. All
physiologists admit that the roots of plants absorb the salts of
ammonia brought to them by the rain; and fourteen gallons of rain-water
contain* a grain of ammonia, therefore only a little more than twice as
much as in the weakest solution employed by me. The fact which appears
truly wonderful is, that the one-twenty-millionth of a grain of the
phosphate of ammonia (including less than the one-thirty-millionth of
efficient matter), when absorbed by a gland, should induce some change
in it, which leads to a motor impulse being transmitted down the whole
length of the tentacle, causing the basal part to bend, often through
an angle of above 180 degrees.

Astonishing as is this result, there is no sound reason

* Miller's 'Elements of Chemistry,' part ii. p. 107, 3rd edit. 1864.
[page 173]

why we should reject it as incredible. Prof. Donders, of Utrecht,
informs me that from experiments formerly made by him and Dr. De
Ruyter, he inferred that less than the one-millionth of a grain of
sulphate of atropine, in an extremely diluted state, if applied
directly to the iris of a dog, paralyses the muscles of this organ.
But, in fact, every time that we perceive an odour, we have evidence
that infinitely smaller particles act on our nerves.  When a dog stands
a quarter of a mile to leeward of a deer or other animal, and perceives
its presence, the odorous particles produce some change in the
olfactory nerves; yet these particles must be infinitely smaller* than
those of the phosphate of ammonia weighing the one-twenty-millionth of
a grain. These nerves then transmit some influence to the brain of the
dog, which leads to action on its part. With Drosera, the really
marvellous fact is, that a plant without any specialised nervous system
should be affected by such minute particles; but we have no grounds for
assuming that other tissues could not be rendered as exquisitely
susceptible to impressions from without if this were beneficial to the
organism, as is the nervous system of the higher animals.

* My son, George Darwin, has calculated for me the diameter of a sphere
of phosphate of ammonia (specific gravity 1.678), weighing the
one-twenty-millionth of a grain, and finds it to be 1/1644 of an inch.
Now, Dr. Klein informs me that the smallest Micrococci, which are
distinctly discernible under a power of 800 diameters, are estimated to
be from .0002 to
.0005 of a millimetre--that is, from 1/50800 to 1/127000 of an inch--in diameter. Therefore,
an object between 1/31 and 1/77 of the size of a sphere of the
phosphate of ammonia of the above weight can be seen under a high
power; and no one supposes that odorous particles, such as those
emitted from the deer in the above illustration, could be seen under
any power of the microscope.) [page 174]


                         CHAPTER VIII.

  THE EFFECTS OF VARIOUS OTHER SALTS AND ACIDS ON THE LEAVES.

Salts of sodium, potassium, and other alkaline, earthy, and metallic
salts--Summary on the action of these salts--Various acids--Summary on
their action.

HAVING found that the salts of ammonia were so powerful, I was led to
investigate the action of some other salts. It will be convenient,
first, to give a list of the substances tried (including forty-nine
salts and two metallic acids), divided into two columns, showing those
which cause inflection, and those which do not do so, or only
doubtfully. My experiments were made by placing half-minim drops on the
discs of leaves, or, more commonly, by immersing them in the solutions;
and sometimes by both methods. A summary of the results, with some
concluding remarks, will then be given. The action of various acids
will afterwards be described.

COLUMN 1 : SALTS CAUSING INFLECTION.  COLUMN 2 : SALTS NOT CAUSING
INFLECTION.

(Arranged in Groups according to the Chemical Classification in Watts'
'Dictionary of Chemistry.')

Sodium carbonate, rapid inflection. : Potassium carbonate: slowly
poisonous.  Sodium nitrate, rapid inflection. : Potassium nitrate:
somewhat poisonous.  Sodium sulphate, moderately rapid inflection. :
Potassium sulphate.  Sodium phosphate, very rapid inflection. :
Potassium phosphate.  Sodium citrate, rapid inflection. : Potassium
citrate.  Sodium oxalate; rapid inflection.  Sodium chloride,
moderately rapid inflection. : Potassium chloride.  [page 175]

COLUMN 1 : SALTS CAUSING INFLECTION.  COLUMN 2 : SALTS NOT CAUSING
INFLECTION.

(Arranged in Groups according to the Chemical Classification in Watts'
'Dictionary of Chemistry.')

Sodium iodide, rather slow inflection. : Potassium iodide, a slight and
doubtful amount of inflection.  Sodium bromide, moderately rapid
inflection. : Potassium bromide.  Potassium oxalate, slow and doubtful
inflection. :  Lithium nitrate, moderately rapid inflection. : Lithium
acetate.  Caesium chloride, rather slow inflection. : Rubidium
chloride.  Silver nitrate, rapid inflection: quick poison. :  Cadmium
chloride, slow inflection. : Calcium acetate.  Mercury perchloride,
rapid inflection: quick poison. : Calcium nitrate.
 : Magnesium acetate.  : Magnesium nitrate.  : Magnesium chloride.  :
 Magnesium sulphate.  : Barium acetate.  : Barium nitrate.  : Strontium
 acetate.  : Strontium nitrate.  : Zinc chloride.

Aluminium chloride, slow and doubtful inflection. : Aluminium nitrate,
a trace of inflection.  Gold chloride, rapid inflection: quick poison.
: Aluminium and potassium sulphate.

Tin chloride, slow inflection: poisonous. : Lead chloride.

Antimony tartrate, slow inflection: probably poisonous.  Arsenious
acid, quick inflection: poisonous.  Iron chloride, slow inflection:
probably poisonous. : Manganese chloride.  Chromic acid, quick
inflection: highly poisonous.  Copper chloride, rather slow in
flection: poisonous. : Cobalt chloride.  Nickel chloride, rapid
inflection: probably poisonous.  Platinum chloride, rapid inflection:
poisonous.  [page 176]

Sodium, Carbonate of (pure, given me by Prof. Hoffmann).--Half-minims
(.0296 ml.) of a solution of one part to 218 of water (2 grs. to 1 oz.)
were placed on the discs of twelve leaves. Seven of these became well
inflected; three had only two or three of their outer tentacles
inflected, and the remaining two were quite unaffected. But the dose,
though only the 1/480 of a grain (.135 mg.), was evidently too strong,
for three of the seven well-inflected leaves were killed. On the other
hand, one of the seven, which had only a few tentacles inflected,
re-expanded and seemed quite healthy after 48 hrs. By employing a
weaker solution (viz. one part to 437 of water, or 1 gr. to 1 oz.),
doses of 1/960 of a grain (.0675 mg.) were given to six leaves. Some of
these were affected in 37 m.; and in 8 hrs. the outer tentacles of all,
as well as the blades of two, were considerably inflected. After 23
hrs. 15 m.  the tentacles had almost re-expanded, but the blades of the
two were still just perceptibly curved inwards. After 48 hrs. all six
leaves were fully re-expanded, and appeared perfectly healthy.

Three leaves were immersed, each in thirty minims of a solution of one
part to 875 of water (1 gr. to 2 oz.), so that each received 1/32 of a
grain (2.02 mg.); after 40 m. the three were much affected, and after 6
hrs. 45 m. the tentacles of all and the blade of one closely
inflected.

Sodium, Nitrate of (pure).--Half-minims of a solution of one part to
437 of water, containing 1/960 of a grain (.0675 mg.), were placed on
the discs of five leaves. After 1 hr. 25 m. the tentacles of nearly
all, and the blade of one, were somewhat inflected. The inflection
continued to increase, and in 21 hrs. 15 m. the tentacles and the
blades of four of them were greatly affected, and the blade of the
fifth to a slight extent. After an additional 24 hrs. the four leaves
still remained closely inflected, whilst the fifth was beginning to
expand. Four days after the solution had been applied, two of the
leaves had quite, and one had partially, re-expanded; whilst the
remaining two remained closely inflected and appeared injured.

Three leaves were immersed, each in thirty minims of a solution of one
part to 875 of water; in 1 hr. there was great inflection, and after 8
hrs. 15 m. every tentacle and the blades of all three were most
strongly inflected.

Sodium, Sulphate of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves. After 5 hrs. 30 m. the
tentacles of three of them, (with the blade of one) were considerably;
and those of the other three slightly, inflected. After 21 hrs. the
inflection had a little decreased, [page 177] and in 45 hrs. the leaves
were fully expanded, appearing quite healthy.

Three leaves were immersed, each in thirty minims of a solution of one
part of the sulphate to 875 of water; after 1 hr. 30 m. there was some
inflection, which increased so much that in 8 hrs. 10 m. all the
tentacles and the blades of all three leaves were closely inflected.

Sodium, Phosphate of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves. The solution acted with
extraordinary rapidity, for in 8 m. the outer tentacles on several of
the leaves were much incurved. After 6 hrs. the tentacles of all six
leaves, and the blades of two, were closely inflected. This state of
things continued for 24 hrs., excepting that the blade of a third leaf
became incurved. After 48 hrs. all the leaves re-expanded. It is clear
that 1/960 of a grain of phosphate of soda has great power in causing
inflection.

Sodium, Citrate of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves, but these were not
observed until 22 hrs. had elapsed. The sub-marginal tentacles of five
of them, and the blades of four, were then found inflected; but the
outer rows of tentacles were not affected. One leaf, which appeared
older than the others, was very little affected in any way. After 46
hrs. four of the leaves were almost re-expanded, including their
blades. Three leaves were also immersed, each in thirty minims of a
solution of one part of the citrate to 875 of water; they were much
acted on in 25 m.; and after 6 hrs. 35 m.  almost all the tentacles,
including those of the outer rows, were inflected, but not the blades.

Sodium, Oxalate of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of seven leaves; after 5 hrs. 30 m. the
tentacles of all, and the blades of most of them, were much affected.
In 22 hrs., besides the inflection of the tentacles, the blades of all
seven leaves were so much doubled over that their tips and bases almost
touched. On no other occasion have I seen the blades so strongly
affected. Three leaves were also immersed, each in thirty minims of a
solution of one part to 875 of water; after 30 m. there was much
inflection, and after 6 hrs. 35 m. the blades of two and the tentacles
of all were closely inflected.

Sodium, Chloride of (best culinary salt).--Half-minims of a solution of
one part to 218 of water were placed on the discs [page 178] of four
leaves. Two, apparently, were not at all affected in 48 hrs.; the third
had its tentacles slightly inflected; whilst the fourth had almost all
its tentacles inflected in 24 hrs., and these did not begin to
re-expand until the fourth day, and were not perfectly expanded on the
seventh day. I presume that this leaf was injured by the salt.
Half-minims of a weaker solution, of one part to 437 of water, were
then dropped on the discs of six leaves, so that each received 1/960 of
a grain. In 1 hr. 33 m. there was slight inflection; and after 5 hrs.
30 m. the tentacles of all six leaves were considerably, but not
closely, inflected. After 23 hrs.  15 m. all had completely
re-expanded, and did not appear in the least injured.

Three leaves were immersed, each in thirty minims of a solution of one
part to 875 of water, so that each received 1/32 of a grain, or 2.02
mg. After 1 hr. there was much inflection; after 8 hrs. 30 m. all the
tentacles and the blades of all three were closely inflected. Four
other leaves were also immersed in the solution, each receiving the
same amount of salt as before, viz. 1/32 of a grain. They all soon
became inflected; after 48 hrs. they began to re-expand, and appeared
quite uninjured, though the solution was sufficiently strong to taste
saline.

Sodium, Iodide of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves. After 24 hrs. four of
them had their blades and many tentacles inflected.  The other two had
only their submarginal tentacles inflected; the outer ones in most of
the leaves being but little affected. After 46 hrs. the leaves had
nearly re-expanded. Three leaves were also immersed, each in thirty
minims of a solution of one part to 875 of water. After 6 hrs. 30 m.
almost all the tentacles, and the blade of one leaf, were closely
inflected.

Sodium, Bromide of.--Half-minims of a solution of one part to 437 of
water were placed on six leaves. After 7 hrs. there was some
inflection; after 22 hrs. three of the leaves had their blades and most
of their tentacles inflected; the fourth leaf was very slightly, and
the fifth and sixth hardly at all, affected. Three leaves were also
immersed, each in thirty minims of a solution of one part to 875 of
water; after 40 m. there was some inflection; after 4 hrs. the
tentacles of all three leaves and the blades of two were inflected.
These leaves were then placed in water, and after 17 hrs. 30 m. two of
them were almost completely, and the third partially, re-expanded; so
that apparently they were not injured.  [page 179]

Potassium, Carbonate of (pure).--Half-minims of a solution of one part
to 437 of water were placed on six leaves. No effect was produced in 24
hrs.; but after 48 hrs. some of the leaves had their tentacles, and one
the blade, considerably inflected. This, however, seemed the result of
their being injured; for on the third day after the solution was given,
three of the leaves were dead, and one was very unhealthy; the other
two were recovering, but with several of their tentacles apparently
injured, and these remained permanently inflected. It is evident that
the 1/960 of a grain of this salt acts as a poison. Three leaves were
also immersed, each in thirty minims of a solution of one part to 875
of water, though only for 9 hrs.; and, very differently from what
occurs with the salts of soda, no inflection ensued.

Potassium, Nitrate of.--Half-minims of a strong solution, of one part
to 109 of water (4 grs. to 1 oz.), were placed on the discs of four
leaves; two were much injured, but no inflection ensued. Eight leaves
were treated in the same manner, with drops of a weaker solution, of
one part to 218 of water. After 50 hrs. there was no inflection, but
two of the leaves seemed injured. Five of these leaves were
subsequently tested with drops of milk and a solution of gelatine on
their discs, and only one became inflected; so that the solution of the
nitrate of the above strength, acting for 50 hrs., apparently had
injured or paralysed the leaves. Six leaves were then treated in the
same manner with a still weaker solution, of one part to 437 of water,
and these, after 48 hrs., were in no way affected, with the exception
of perhaps a single leaf. Three leaves were next immersed for 25 hrs.,
each in thirty minims of a solution of one part to 875 of water, and
this produced no apparent effect. They were then put into a solution of
one part of carbonate of ammonia to 218 of water; the glands were
immediately blackened, and after 1 hr. there was some inflection, and
the protoplasmic contents of the cells became plainly aggregated. This
shows that the leaves had not been much injured by their immersion for
25 hrs. in the nitrate.

Potassium, Sulphate of.--Half-minims of a solution of one part to 437
of water were placed on the discs of six leaves. After 20 hrs. 30 m. no
effect was produced; after an additional 24 hrs. three remained quite
unaffected; two seemed injured, and the sixth seemed almost dead with
its tentacles inflected. Nevertheless, after two additional days, all
six leaves recovered.  The immersion of three leaves for 24 hrs., each
in thirty minims of [page 180] a solution of one part to 875 of water,
produced no apparent effect. They were then treated with the same
solution of carbonate of ammonia, with the same result as in the case
of the nitrate of potash.

Potassium, Phosphate of.--Half-minims of a solution of one part to 437
of water were placed on the discs of six leaves, which were observed
during three days; but no effect was produced. The partial drying up of
the fluid on the disc slightly drew together the tentacles on it, as
often occurs in experiments of this kind. The leaves on the third day
appeared quite healthy.

Potassium, Citrate of.--Half-minims of a solution of one part to 437 of
water, left on the discs of six leaves for three days, and the
immersion of three leaves for 9 hrs., each in 30 minims of a solution
of one part to 875 of water, did not produce the least effect.

Potassium, Oxalate of.--Half-minims were placed on different occasions
on the discs of seventeen leaves; and the results perplexed me much, as
they still do. Inflection supervened very slowly. After 24 hrs. four
leaves out of the seventeen were well inflected, together with the
blades of two; six were slightly affected, and seven not at all. Three
leaves of one lot were observed for five days, and all died; but in
another lot of six, all excepting one looked healthy after four days.
Three leaves were immersed during 9 hrs., each in 30 minims of a
solution of one part to 875 of water, and were not in the least
affected; but they ought to have been observed for a longer time.

Potassium, Chloride of. Neither half-minims of a solution of one part
to 437 of water; left on the discs of six leaves for three days, nor
the immersion of three leaves during 25 hrs., in 30 minims of a
solution of one part to 875 of water, produced the least effect. The
immersed leaves were then treated with carbonate of ammonia, as
described under nitrate of potash, and with the same result.

Potassium, Iodide of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of seven leaves. In 30 m. one leaf had
the blade inflected; after some hours three leaves had most of their
submarginal tentacles moderately inflected; the remaining three being
very slightly affected. Hardly any of these leaves had their outer
tentacles inflected.  After 21 hrs. all re-expanded, excepting two
which still had a few submarginal tentacles inflected. Three leaves
were next [page 181] immersed for 8 hrs. 40 m., each in 30 minims of a
solution of one part to 875 of water, and were not in the least
affected. I do not know what to conclude from this conflicting
evidence; but it is clear that the iodide of potassium does not
generally produce any marked effect.

Potassium, Bromide of.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves; after 22 hrs. one had its
blade and many tentacles inflected, but I suspect that an insect might
have alighted on it and then escaped; the five other leaves were in no
way affected. I tested three of these leaves with bits of meat, and
after 24 hrs. they became splendidly inflected. Three leaves were also
immersed for 21 hrs. in 30 minims of a solution of one part to 875 of
water; but they were not at all affected, excepting that the glands
looked rather pale.

Lithium, Acetate of.--Four leaves were immersed together in a vessel
containing 120 minims of a solution of one part to 437 of water; so
that each received, if the leaves absorbed equally, 1/16 of a grain.
After 24 hrs. there was no inflection. I then added, for the sake of
testing the leaves, some strong solution (viz. 1 gr. to 20 oz., or one
part to 8750 of water) of phosphate of ammonia, and all four became in
30 m. closely inflected.

Lithium, Nitrate of.--Four leaves were immersed, as in the last case,
in 120 minims of a solution of one part to 437 of water; after 1 h. 30
m. all four were a little, and after 24 hrs.  greatly, inflected. I
then diluted the solution with some water, but they still remained
somewhat inflected on the third day.

Caesium, Chloride of.--Four leaves were immersed, as above, in 120
minims of a solution of one part to 437 of water. After 1 hr. 5 m. the
glands were darkened; after 4 hrs. 20 m. there was a trace of
inflection; after 6 hrs. 40 m. two leaves were greatly, but not
closely, and the other two considerably inflected. After 22 hrs. the
inflection was extremely great, and two had their blades inflected. I
then transferred the leaves into water, and in 46 hrs. from their first
immersion they were almost re-expanded.

Rubidium, Chloride of.--Four leaves which were immersed, as above, in
120 minims of a solution of one part to 437 of water, were not acted on
in 22 hrs. I then added some of the strong solution (1 gr. to 20 oz.)
of phosphate of ammonia, and in 30 m. all were immensely inflected.

Silver, Nitrate of.--Three leaves were immersed in ninety [page 182]
minims of a solution of one part to 437 of water; so that each
received, as before, 1/16 of a grain. After 5 m. slight inflection, and
after 11 m. very strong inflection, the glands becoming excessively
black; after 40 m. all the tentacles were closely inflected. After 6
hrs. the leaves were taken out of the solution, washed, and placed in
water; but next morning they were evidently dead.

Calcium, Acetate of.--Four leaves were immersed in 120 minims of a
solution of one part to 437 of water; after 24 hrs. none of the
tentacles were inflected, excepting a few where the blade joined the
petiole; and this may have been caused by the absorption of the salt by
the cut-off end of the petiole. I then added some of the solution (1
gr. to 20 oz.) of phosphate of ammonia, but this to my surprise excited
only slight inflection, even after 24 hrs. Hence it would appear that
the acetate had rendered the leaves torpid.

Calcium, Nitrate of.--Four leaves were immersed in 120 minims of a
solution of one part to 437 of water, but were not affected in 24 hrs.
I then added some of the solution of phosphate of ammonia (1 gr. to 20
oz.), but this caused only very slight inflection after 24 hrs. A fresh
leaf was next put into a mixed solution of the above strengths of the
nitrate of calcium and phosphate of ammonia, and it became closely
inflected in between 5 m. and 10 m.  Half-minims of a solution of one
part of the nitrate of calcium to 218 of water were dropped on the
discs of three leaves, but produced no effect.

Magnesium, Acetate, Nitrate, and Chloride of.--Four leaves were
immersed in 120 minims of solutions, of one part to 437 of water, of
each of these three salts; after 6 hrs. there was no inflection; but
after 22 hrs. one of the leaves in the acetate was rather more
inflected than generally occurs from an immersion for this length of
time in water. Some of the solution (1 gr. to 20 oz.) of phosphate of
ammonia was then added to the three solutions. The leaves in the
acetate mixed with the phosphate underwent some inflection; and this
was well pronounced after 24 hrs. Those in the mixed nitrate were
decidedly inflected in 4 hrs. 30 m., but the degree of inflection did
not afterwards much increase; whereas the four leaves in the mixed
chloride were greatly inflected in a few minutes, and after 4 hrs. had
almost every tentacle closely inflected. We thus see that the acetate
and nitrate of magnesium injure the leaves, or at least prevent the
subsequent action of phosphate of ammonia; whereas the chloride has no
such tendency.  [page 183]

Magnesium, Sulphate of.--Half-minims of a solution of one part to 218
of water were placed on the discs of ten leaves, and produced no
effect.

Barium, Acetate of.--Four leaves were immersed in 120 minims of a
solution of one part to 437 of water, and after 22 hrs. there was no
inflection, but the glands were blackened. The leaves were then placed
in a solution (1 gr. to 20 oz.) of phosphate of ammonia, which caused
after 26 hrs. only a little inflection in two of the leaves.

Barium, Nitrate of.--Four leaves were immersed in 120 minims of a
solution of one part to 437 of water; and after 22 hrs. there was no
more than that slight degree of inflection, which often follows from an
immersion of this length in pure water. I then added some of the same
solution of phosphate of ammonia, and after 30 m. one leaf was greatly
inflected, two others moderately, and the fourth not at all. The leaves
remained in this state for 24 hrs.

Strontium, Acetate of.--Four leaves, immersed in 120 minims of a
solution of one part to 437 of water, were not affected in 22 hrs. They
were then placed in some of the same solution of phosphate of ammonia,
and in 25 m. two of them were greatly inflected; after 8 hrs. the third
leaf was considerably inflected, and the fourth exhibited a trace of
inflection. They were in the same state next morning.

Strontium, Nitrate of.--Five leaves were immersed in 120 minims of a
solution of one part to 437 of water; after 22 hrs. there was some
slight inflection, but not more than sometimes occurs with leaves in
water. They were then placed in the same solution of phosphate of
ammonia; after 8 hrs. three of them were moderately inflected, as were
all five after 24 hrs.; but not one was closely inflected. It appears
that the nitrate of strontium renders the leaves half torpid.

Cadmium, Chloride of.--Three leaves were immersed in ninety minims of a
solution of one part to 437 of water; after 5 hrs. 20 m. slight
inflection occurred, which increased during the next three hours. After
24 hrs. all three leaves had their tentacles well inflected, and
remained so for an additional 24 hrs.; glands not discoloured.

Mercury, Perchloride of.--Three leaves were immersed in ninety minims
of a solution of one part to 437 of water; after 22 m. there was some
slight inflection, which in 48 m. became well pronounced; the glands
were now blackened. After 5 hrs. 35 m. all the tentacles closely
inflected; after 24 hrs. still [page 184] inflected and discoloured.
The leaves were then removed and left for two days in water; but they
never re-expanded, being evidently dead.

Zinc, Chloride of.--Three leaves immersed in ninety minims of a
solution of one part to 437 of water were not affected in 25 hrs. 30
m.

Aluminium, Chloride of.--Four leaves were immersed in 120 minims of a
solution of one part to 437 of water; after 7 hrs. 45 m. no inflection;
after 24 hrs. one leaf rather closely, the second moderately, the third
and fourth hardly at all, inflected. The evidence is doubtful, but I
think some power in slowly causing inflection must be attributed to
this salt. These leaves were then placed in the solution (1 gr. to 20
oz.) of phosphate of ammonia, and after 7 hrs. 30 m. the three, which
had been but little affected by the chloride, became rather closely
inflected.

Aluminium, Nitrate of.--Four leaves were immersed in 120 minims of a
solution of one part to 437 of water; after 7 hrs. 45 m. there was only
a trace of inflection; after 24 hrs. one leaf was moderately inflected.
The evidence is here again doubtful, as in the case of the chloride of
aluminium. The leaves were then transferred to the same solution, as
before, of phosphate of ammonia; this produced hardly any effect in 7
hrs. 30 m.; but after 25 hrs. one leaf was pretty closely inflected,
the three others very slightly, perhaps not more so than from water.

Aluminium and Potassium, Sulphate of (common alum).--Half-minims of a
solution of the usual strength were placed on the discs of nine leaves,
but produced no effect.

Gold, Chloride of.--Seven leaves were immersed in so much of a solution
of one part to 437 of water that each received 30 minims, containing
1/16 of a grain, or 4.048 mg., of the chloride. There was some
inflection in 8 m., which became extreme in 45 m. In 3 hrs. the
surrounding fluid was coloured purple, and the glands were blackened.
After 6 hrs. the leaves were transferred to water; next morning they
were found discoloured and evidently killed.  The secretion decomposes
the chloride very readily; the glands themselves becoming coated with
the thinnest layer of metallic gold, and particles float about on the
surface of the surrounding fluid.

Lead, Chloride of.--Three leaves were immersed in ninety minims of a
solution of one part to 437 of water. After 23 hrs. there was not a
trace of inflection; the glands were not blackened, and the leaves did
not appear injured. They were then trans- [page 185] ferred to the
solution (1 gr. to 20 oz.) of phosphate of ammonia, and after 24 hrs.
two of them were somewhat, the third very little, inflected; and they
thus remained for another 24 hrs.

Tin, Chloride of.--Four leaves were immersed in 120 minims of a
solution of about one part (all not being dissolved) to 437 of water.
After 4 hrs. no effect; after 6 hrs. 30 m. all four leaves had their
submarginal tentacles inflected; after 22 hrs. every single tentacle
and the blades were closely inflected. The surrounding fluid was now
coloured pink. The leaves were washed and transferred to water, but
next morning were evidently dead. This chloride is a deadly poison, but
acts slowly.

Antimony, Tartrate of.--Three leaves were immersed in ninety minims of
a solution of one part to 437 of water. After 8 hrs. 30 m. there was
slight inflection; after 24 hrs. two of the leaves were closely, and
the third moderately, inflected; glands not much darkened. The leaves
were washed and placed in water, but they remained in the same state
for 48 additional hours. This salt is probably poisonous, but acts
slowly.

Arsenious Acid.--A solution of one part to 437 of water; three leaves
were immersed in ninety minims; in 25 m. considerable inflection; in 1
h. great inflection; glands not discoloured. After 6 hrs. the leaves
were transferred to water; next morning they looked fresh, but after
four days were pale-coloured, had not re-expanded, and were evidently
dead.

Iron, Chloride of.--Three leaves were immersed in ninety minims of a
solution of one part to 437 of water; in 8 hrs. no inflection; but
after 24 hrs. considerable inflection; glands blackened; fluid coloured
yellow, with floating flocculent particles of oxide of iron. The leaves
were then placed in water; after 48 hrs. they had re-expanded a very
little, but I think were killed; glands excessively black.

Chromic Acid.--One part to 437 of water; three leaves were immersed in
ninety minims; in 30 m. some, and in 1 hr. considerable, inflection;
after 2 hrs. all the tentacles closely inflected, with the glands
discoloured. Placed in water, next day leaves quite discoloured and
evidently killed.

Manganese, Chloride of.--Three leaves immersed in ninety minims of a
solution of one part to 437 of water; after 22 hrs. no more inflection
than often occurs in water; glands not blackened. The leaves were then
placed in the usual solution of phosphate of ammonia, but no inflection
was caused even after 48 hrs.

Copper, Chloride of.--Three leaves immersed in ninety minims [page 186]
of a solution of one part to 437 of water; after 2 hrs. some
inflection; after 3 hrs. 45 m.  tentacles closely inflected, with the
glands blackened. After 22 hrs. still closely inflected, and the leaves
flaccid. Placed in pure water, next day evidently dead. A rapid
poison.

Nickel, Chloride of.--Three leaves immersed in ninety minims of a
solution of one part to 437 of water; in 25 m. considerable inflection,
and in 3 hrs. all the tentacles closely inflected.  After 22 hrs. still
closely inflected; most of the glands, but not all, blackened. The
leaves were then placed in water; after 24 hrs. remained inflected;
were somewhat discoloured, with the glands and tentacles dingy red.
Probably killed.

Cobalt, Chloride of.--Three leaves immersed in ninety minims of a
solution of one part to 437 of water; after 23 hrs. there was not a
trace of inflection, and the glands were not more blackened than often
occurs after an equally long immersion in water.

Platinum, Chloride of.--Three leaves immersed in ninety minims of a
solution of one part to 437 of water; in 6 m. some inflection, which
became immense after 48 m. After 3 hrs. the glands were rather pale.
After 24 hrs. all the tentacles still closely inflected; glands
colourless; remained in same state for four days; leaves evidently
killed.]

Concluding Remarks on the Action of the foregoing Salts.--Of the
fifty-one salts and metallic acids which were tried, twenty-five caused
the tentacles to be inflected, and twenty-six had no such effect, two
rather doubtful cases occurring in each series. In the table at the
head of this discussion, the salts are arranged according to their
chemical affinities; but their action on Drosera does not seem to be
thus governed. The nature of the base is far more important, as far as
can be judged from the few experiments here given, than that of the
acid; and this is the conclusion at which physiologists have arrived
with respect to animals. We see this fact illustrated in all the nine
salts of soda causing inflection, and in not being poisonous except
when given in large doses; whereas seven of [page 187] the
corresponding salts of potash do not cause inflection, and some of them
are poisonous.  Two of them, however, viz. the oxalate and iodide of
potash, slowly induced a slight and rather doubtful amount of
inflection. This difference between the two series is interesting, as
Dr. Burdon Sanderson informs me that sodium salts may be introduced in
large doses into the circulation of mammals without any injurious
effects; whilst small doses of potassium salts cause death by suddenly
arresting the movements of the heart. An excellent instance of the
different action of the two series is presented by the phosphate of
soda quickly causing vigorous inflection, whilst phosphate of potash is
quite inefficient. The great power of the former is probably due to the
presence of phosphorus, as in the cases of phosphate of lime and of
ammonia. Hence we may infer that Drosera cannot obtain phosphorus from
the phosphate of potash. This is remarkable, as I hear from Dr. Burdon
Sanderson that phosphate of potash is certainly decomposed within the
bodies of animals. Most of the salts of soda act very rapidly; the
iodide acting slowest. The oxalate, nitrate, and citrate seem to have a
special tendency to cause the blade of the leaf to be inflected. The
glands of the disc, after absorbing the citrate, transmit hardly any
motor impulse to the outer tentacles; and in this character the citrate
of soda resembles the citrate of ammonia, or a decoction of
grass-leaves; these three fluids all acting chiefly on the blade.

It seems opposed to the rule of the preponderant influence of the base
that the nitrate of lithium causes moderately rapid inflection, whereas
the acetate causes none; but this metal is closely allied to sodium
[page 188] and potassium,* which act so differently; therefore we might
expect that its action would be intermediate. We see, also, that
caesium causes inflection, and rubidium does not; and these two metals
are allied to sodium and potassium. Most of the earthy salts are
inoperative. Two salts of calcium, four of magnesium, two of barium,
and two of strontium, did not cause any inflection, and thus follow the
rule of the preponderant power of the base. Of three salts of
aluminium, one did not act, a second showed a trace of action, and the
third acted slowly and doubtfully, so that their effects are nearly
alike.

Of the salts and acids of ordinary metals, seventeen were tried, and
only four, namely those of zinc, lead, manganese, and cobalt, failed to
cause inflection. The salts of cadmium, tin, antimony, and iron, act
slowly; and the three latter seem more or less poisonous. The salts of
silver, mercury, gold, copper, nickel, and platinum, chromic and
arsenious acids, cause great inflection with extreme quickness, and are
deadly poisons. It is surprising, judging from animals, that lead and
barium should not be poisonous. Most of the poisonous salts make the
glands black, but chloride of platinum made them very pale. I shall
have occasion, in the next chapter, to add a few remarks on the
different effects of phosphate of ammonia on leaves previously immersed
in various solutions.

                            ACIDS.

I will first give, as in the case of the salts, a list of the
twenty-four acids which were tried, divided into two series, according
as they cause or do not cause

* Miller's 'Elements of Chemistry,' 3rd edit. pp. 337, 448.  [page 189]
inflection. After describing the experiments, a few concluding remarks
will be added.

ACIDS, MUCH DILUTED, WHICH CAUSE INFLECTION.

1. Nitric, strong inflection; poisonous.  2. Hydrochloric, moderate and
slow inflection; not poisonous.  3. Hydriodic, strong inflection;
poisonous.  4. Iodic, strong inflection; poisonous.  5. Sulphuric,
strong inflection; somewhat poisonous.  6. Phosphoric, strong
inflection; poisonous.  7. Boracic; moderate and rather slow
inflection; not poisonous.  8. Formic, very slight inflection; not
poisonous.  9. Acetic, strong and rapid inflection; poisonous.  10.
Propionic, strong but not very rapid inflection; poisonous.  11. Oleic,
quick inflection; very poisonous.  12. Carbolic, very slow inflection;
poisonous.  13. Lactic, slow and moderate inflection; poisonous.  14.
Oxalic, moderately quick inflection; very poisonous.  15. Malic, very
slow but considerable inflection; not poisonous.  16. Benzoic, rapid
inflection; very poisonous.  17. Succinic, moderately quick inflection:
moderately poisonous.  18. Hippuric, rather slow inflection;
poisonous.  19. Hydrocyanic, rather rapid inflection; very poisonous.

ACIDS, DILUTED TO THE SAME DEGREE, WHICH DO NOT CAUSE INFLECTION.

1. Gallic; not poisonous.  2. Tannic; not poisonous.  3. Tartaric; not
poisonous.  4. Citric; not poisonous.  5. Uric; (?) not poisonous.

Nitric Acid.--Four leaves were placed, each in thirty minims of one
part by weight of the acid to 437 of water, so that each received 1/16
of a grain, or 4.048 mg. This strength was chosen for this and most of
the following experiments, as it is the same [page 190] as that of most
of the foregoing saline solutions. In 2 hrs. 30 m. some of the leaves
were considerably, and in 6 hrs. 30 m. all were immensely, inflected,
as were their blades. The surrounding fluid was slightly coloured pink,
which always shows that the leaves have been injured. They were then
left in water for three days; but they remained inflected and were
evidently killed. Most of the glands had become colourless. Two leaves
were then immersed, each in thirty minims of one part to 1000 of water;
in a few hours there was some inflection; and after 24 hrs. both leaves
had almost all their tentacles and blades inflected; they were left in
water for three days, and one partially re-expanded and recovered. Two
leaves were next immersed, each in thirty minims of one part to 2000 of
water; this produced very little effect, except that most of the
tentacles close to the summit of the petiole were inflected, as if the
acid had been absorbed by the cut-off end.

Hydrochloric Acid.--One part to 437 of water; four leaves were immersed
as before, each in thirty minims. After 6 hrs. only one leaf was
considerably inflected. After 8 hrs. 15 m. one had its tentacles and
blade well inflected; the other three were moderately inflected, and
the blade of one slightly. The surrounding fluid was not coloured at
all pink. After 25 hrs. three of these four leaves began to re-expand,
but their glands were of a pink instead of a red colour; after two more
days they fully re-expanded; but the fourth leaf remained inflected,
and seemed much injured or killed, with its glands white. Four leaves
were then treated, each with thirty minims of one part to 875 of water;
after 21 hrs. they were moderately inflected; and on being transferred
to water, fully re-expanded in two days, and seemed quite healthy.

Hydriodic Acid.--One to 437 of water; three leaves were immersed as
before, each in thirty minims. After 45 m. the glands were discoloured,
and the surrounding fluid became pinkish, but there was no inflection.
After 5 hrs. all the tentacles were closely inflected; and an immense
amount of mucus was secreted, so that the fluid could be drawn out into
long ropes.  The leaves were then placed in water, but never
re-expanded, and were evidently killed. Four leaves were next immersed
in one part to 875 of water; the action was now slower, but after 22
hrs. all four leaves were closely inflected, and were affected in other
respects as above described. These leaves did not re-expand, though
left for four days in water. This acid acts far more powerfully than
hydrochloric, and is poisonous.

Iodic Acid.--One to 437 of water; three leaves were immersed, [page
191] each in thirty minims; after 3 hrs. strong inflection; after 4
hrs. glands dark brown; after 8 hrs. 30 m. close inflection, and the
leaves had become flaccid; surrounding fluid not coloured pink. These
leaves were then placed in water, and next day were evidently dead.

Sulphuric Acid.--One to 437 of water; four leaves were immersed, each
in thirty minims; after 4 hrs. great inflection; after 6 hrs.
surrounding fluid just tinged pink; they were then placed in water, and
after 46 hrs. two of them were still closely inflected, two beginning
to re-expand; many of the glands colourless. This acid is not so
poisonous as hydriodic or iodic acids.

Phosphoric Acid.--One to 437 of water; three leaves were immersed
together in ninety minims; after 5 hrs. 30 m. some inflection, and some
glands colourless; after 8 hrs. all the tentacles closely inflected,
and many glands colourless; surrounding fluid pink. Left in water for
two days and a half, remained in the same state and appeared dead.

Boracic Acid.--One to 437 of water; four leaves were immersed together
in 120 minims; after 6 hrs. very slight inflection; after 8 hrs. 15 m.
two were considerably inflected, the other two slightly. After 24 hrs.
one leaf was rather closely inflected, the second less closely, the
third and fourth moderately. The leaves were washed and put into water;
after 24 hrs. they were almost fully re-expanded and looked healthy.
This acid agrees closely with hydrochloric acid of the same strength in
its power of causing inflection, and in not being poisonous.

Formic Acid.--Four leaves were immersed together in 120 minims of one
part to 437 of water; after 40 m. slight, and after 6 hrs. 30 m. very
moderate inflection; after 22 hrs. only a little more inflection than
often occurs in water. Two of the leaves were then washed and placed in
a solution (1 gr. to 20 oz.) of phosphate of ammonia; after 24 hrs.
they were considerably inflected, with the contents of their cells
aggregated, showing that the phosphate had acted, though not to the
full and ordinary degree.

Acetic Acid.--Four leaves were immersed together in 120 minims of one
part to 437 of water.  In 1 hr. 20 m. the tentacles of all four and the
blades of two were greatly inflected. After 8 hrs. the leaves had
become flaccid, but still remained closely inflected, the surrounding
fluid being coloured pink. They were then washed and placed in water;
next morning they were still inflected and of a very dark red colour,
but with their glands colourless. After another day they were
dingy-coloured, and [page 192] evidently dead. This acid is far more
powerful than formic, and is highly poisonous.  Half-minim drops of a
stronger mixture (viz. one part by measure to 320 of water) were placed
on the discs of five leaves; none of the exterior tentacles, only those
on the borders of the disc which actually absorbed the acid, became
inflected. Probably the dose was too strong and paralysed the leaves,
for drops of a weaker mixture caused much inflection; nevertheless the
leaves all died after two days.

Propionic Acid.--Three leaves were immersed in ninety minims of a
mixture of one part to 437 of water; in 1 hr. 50 m. there was no
inflection; but after 3 hrs. 40 m. one leaf was greatly inflected, and
the other two slightly. The inflection continued to increase, so that
in 8 hrs. all three leaves were closely inflected. Next morning, after
20 hrs., most of the glands were very pale, but some few were almost
black. No mucus had been secreted, and the surrounding fluid was only
just perceptibly tinted of a pale pink. After 46 hrs. the leaves became
slightly flaccid and were evidently killed, as was afterwards proved to
be the case by keeping them in water. The protoplasm in the closely
inflected tentacles was not in the least aggregated, but towards their
bases it was collected in little brownish masses at the bottoms of the
cells. This protoplasm was dead, for on leaving the leaf in a solution
of carbonate of ammonia, no aggregation ensued. Propionic acid is
highly poisonous to Drosera, like its ally acetic acid, but induces
inflection at a much slower rate.

Oleic Acid (given me by Prof. Frankland).--Three leaves were immersed
in this acid; some inflection was almost immediately caused, which
increased slightly, but then ceased, and the leaves seemed killed. Next
morning they were rather shrivelled, and many of the glands had fallen
off the tentacles. Drops of this acid were placed on the discs of four
leaves; in 40 m.  all the tentacles were greatly inflected, excepting
the extreme marginal ones; and many of these after 3 hrs. became
inflected. I was led to try this acid from supposing that it was
present (which does not seem to be the case)* in olive oil, the action
of which is anomalous.  Thus drops of this oil placed on the disc do
not cause the outer tentacles to be inflected; yet when minute drops
were added to the secretion surrounding the glands of the outer
tentacles, these were occasionally, but by no means always, inflected.
Two leaves were also immersed in this oil, and there

* See articles on Glycerine and Oleic Acid in Watts' 'Dict. of
Chemistry.' [page 193]

was no inflection for about 12 hrs.; but after 23 hrs. almost all the
tentacles were inflected.  Three leaves were likewise immersed in
unboiled linseed oil, and soon became somewhat, and in 3 hrs. greatly,
inflected. After 1 hr. the secretion round the glands was coloured
pink. I infer from this latter fact that the power of linseed oil to
cause inflection cannot be attributed to the albumin which it is said
to contain.

Carbolic Acid.--Two leaves were immersed in sixty minims of a solution
of 1 gr. to 437 of water; in 7 hrs. one was slightly, and in 24 hrs.
both were closely, inflected, with a surprising amount of mucus
secreted. These leaves were washed and left for two days in water; they
remained inflected; most of their glands became pale, and they seemed
dead. This acid is poisonous, but does not act nearly so rapidly or
powerfully as might have been expected from its known destructive power
on the lowest organisms. Half-minims of the same solution were placed
on the discs of three leaves; after 24 hrs. no inflection of the outer
tentacles ensued, and when bits of meat were given them, they became
fairly well inflected. Again half-minims of a stronger solution, of one
part to 218 of water, were placed on the discs of three leaves; no
inflection of the outer tentacles ensued; bits of meat were then given
as before; one leaf alone became well inflected, the discal glands of
the other two appearing much injured and dry. We thus see that the
glands of the discs, after absorbing this acid, rarely transmit any
motor impulse to the outer tentacles; though these, when their own
glands absorb the acid, are strongly acted on.

Lactic Acid.--Three leaves were immersed in ninety minims of one part
to 437 of water.  After 48 m. there was no inflection, but the
surrounding fluid was coloured pink; after 8 hrs.  30 m. one leaf alone
was a little inflected, and almost all the glands on all three leaves
were of a very pale colour. The leaves were then washed and placed in a
solution (1 gr. to 20 oz.) of phosphate of ammonia; after about 16 hrs.
there was only a trace of inflection. They were left in the phosphate
for 48 hrs., and remained in the same state, with almost all their
glands discoloured. The protoplasm within the cells was not aggregated,
except in a very few tentacles, the glands of which were not much
discoloured. I believe, therefore, that almost all the glands and
tentacles had been killed by the acid so suddenly that hardly any
inflection was caused. Four leaves were next immersed in 120 minims of
a weaker solution, of one part to 875 of water; after 2 hrs. 30 m. the
surrounding fluid was quite pink; the glands were pale, but [page 194]
there was no inflection; after 7 hrs. 30 m. two of the leaves showed
some inflection, and the glands were almost white; after 21 hrs. two of
the leaves were considerably inflected, and a third slightly; most of
the glands were white, the others dark red. After 45 hrs. one leaf had
almost every tentacle inflected; a second a large number; the third and
fourth very few; almost all the glands were white, excepting those on
the discs of two of the leaves, and many of these were very dark red.
The leaves appeared dead. Hence lactic acid acts in a very peculiar
manner, causing inflection at an extraordinarily slow rate, and being
highly poisonous. Immersion in even weaker solutions, viz. of one part
to 1312 and 1750 of water, apparently killed the leaves (the tentacles
after a time being bowed backwards), and rendered the glands white, but
caused no inflection.

Gallic, Tannic, Tartaric, and Citric Acids.--One part to 437 of water.
Three or four leaves were immersed, each in thirty minims of these four
solutions, so that each leaf received 1/16 of a grain, or 4.048 mg. No
inflection was caused in 24 hrs., and the leaves did not appear at all
injured. Those which had been in the tannic and tartaric acids were
placed in a solution (1 gr. to 20 oz.) of phosphate of ammonia, but no
inflection ensued in 24 hrs. On the other hand, the four leaves which
had been in the citric acid, when treated with the phosphate, became
decidedly inflected in 50 m. and strongly inflected after 5 hrs., and
so remained for the next 24 hrs.

Malic Acid.--Three leaves were immersed in ninety minims of a solution
of one part to 437 of water; no inflection was caused in 8 hrs. 20 m.,
but after 24 hrs. two of them were considerably, and the third
slightly, inflected--more so than could be accounted for by the action
of water. No great amount of mucus was secreted. They were then placed
in water, and after two days partially re-expanded. Hence this acid is
not poisonous.

Oxalic Acid.--Three leaves were immersed in ninety minims of a solution
of 1 gr. to 437 of water; after 2 hrs. 10 m. there was much inflection;
glands pale; the surrounding fluid of a dark pink colour; after 8 hrs.
excessive inflection. The leaves were then placed in water; after about
16 hrs. the tentacles were of a very dark red colour, like those of the
leaves in acetic acid. After 24 additional hours, the three leaves were
dead and their glands colourless.

Benzoic Acid.--Five leaves were immersed, each in thirty minims of a
solution of 1 gr. to 437 of water. This solution was so weak that it
only just tasted acid, yet, as we shall see, was highly poisonous to
Drosera. After 52 m. the submarginal [page 195] tentacles were somewhat
inflected, and all the glands very pale-coloured; the surrounding fluid
was coloured pink. On one occasion the fluid became pink in the course
of only 12 m., and the glands as white as if the leaf had been dipped
in boiling water. After 4 hrs. much inflection; but none of the
tentacles were closely inflected, owing, as I believe, to their having
been paralysed before they had time to complete their movement. An
extraordinary quantity of mucus was secreted. Some of the leaves were
left in the solution; others, after an immersion of 6 hrs. 30 m., were
placed in water. Next morning both lots were quite dead; the leaves in
the solution being flaccid, those in the water (now coloured yellow) of
a pale brown tint, and their glands white.

Succinic Acid.--Three leaves were immersed in ninety minims of a
solution of 1 gr. to 437 of water; after 4 hrs. 15 m. considerable and
after 23 hrs. great inflection; many of the glands pale; fluid coloured
pink. The leaves were then washed and placed in water; after two days
there was some re-expansion, but many of the glands were still white.
This acid is not nearly so poisonous as oxalic or benzoic.

Uric Acid.--Three leaves were immersed in 180 minims of a solution of 1
gr. to 875 of warm water, but all the acid was not dissolved; so that
each received nearly 1/16 of a grain. After 25 m. there was some slight
inflection, but this never increased; after 9 hrs. the glands were not
discoloured, nor was the solution coloured pink; nevertheless much
mucus was secreted.  The leaves were then placed in water, and by next
morning fully re-expanded. I doubt whether this acid really causes
inflection, for the slight movement which at first occurred may have
been due to the presence of a trace of albuminous matter. But it
produces some effect, as shown by the secretion of so much mucus.

Hippuric Acid.--Four leaves were immersed in 120 minims of a solution
of 1 gr. to 437 of water. After 2 hrs. the fluid was coloured pink;
glands pale, but no inflection. After 6 hrs.  some inflection; after 9
hrs. all four leaves greatly inflected; much mucus secreted; all the
glands very pale. The leaves were then left in water for two days; they
remained closely inflected, with their glands colourless, and I do not
doubt were killed.

Hydrocyanic Acid.--Four leaves were immersed, each in thirty minims of
one part to 437 of water; in 2 hrs. 45 m. all the tentacles were
considerably inflected, with many of the glands pale; after 3 hrs. 45
m. all strongly inflected, and the surrounding fluid coloured pink;
after 6 hrs. all closely inflected. After [page 196] an immersion of 8
hrs. 20 m. the leaves were washed and placed in water; next morning,
after about 16 hrs., they were still inflected and discoloured; on the
succeeding day they were evidently dead. Two leaves were immersed in a
stronger mixture, of one part to fifty of water; in 1 hr. 15 m. the
glands became as white as porcelain, as if they had been dipped in
boiling water; very few of the tentacles were inflected; but after 4
hrs. almost all were inflected. These leaves were then placed in water,
and next morning were evidently dead.  Half-minim drops of the same
strength (viz. one part to fifty of water) were next placed on the
discs of five leaves; after 21 hrs. all the outer tentacles were
inflected, and the leaves appeared much injured. I likewise touched the
secretion round a large number of glands with minute drops (about 1/20
of a minim, or .00296 ml.) of Scheele's mixture (6 per cent.); the
glands first became bright red, and after 3 hrs. 15 m. about two-thirds
of the tentacles bearing these glands were inflected, and remained so
for the two succeeding days, when they appeared dead.]

Concluding Remarks on the Action of Acids.--It is evident that acids
have a strong tendency to cause the inflection of the tentacles;* for
out of the twenty-four acids tried, nineteen thus acted, either rapidly
and energetically, or slowly and slightly. This fact is remarkable, as
the juices of many plants contain more acid, judging by the taste, than
the solutions employed in my experiments. From the powerful effects of
so many acids on Drosera, we are led to infer that those naturally
contained in the tissues of this plant, as well as of others, must play
some important part in their economy. Of the five cases in which acids
did not cause the tentacles to be inflected, one is doubtful; for uric
acid did act slightly, and caused a copious secretion of mucus. Mere
sourness to the taste is no

* According to M. Fournier ('De la Fcondation dans les Phanrogames.'
1863, p. 61) drops of acetic, hydrocyanic, and sulphuric acid cause the
stamens of Berberis instantly to close; though drops of water have no
such power, which latter statement I can confirm; [page 197]

criterion of the power of an acid on Drosera, as citric and tartaric
acids are very sour, yet do not excite inflection. It is remarkable how
acids differ in their power. Thus, hydrochloric acid acts far less
powerfully than hydriodic and many other acids of the same strength,
and is not poisonous. This is an interesting fact, as hydrochloric acid
plays so important a part in the digestive process of animals. Formic
acid induces very slight inflection, and is not poisonous; whereas its
ally, acetic acid, acts rapidly and powerfully, and is poisonous. Malic
acid acts slightly, whereas citric and tartaric acids produce no
effect. Lactic acid is poisonous, and is remarkable from inducing
inflection only after a considerable interval of time. Nothing
surprised me more than that a solution of benzoic acid, so weak as to
be hardly acidulous to the taste, should act with great rapidity and be
highly poisonous; for I am informed that it produces no marked effect
on the animal economy. It may be seen, by looking down the list at the
head of this discussion, that most of the acids are poisonous, often
highly so. Diluted acids are known to induce negative osmose,* and the
poisonous action of so many acids on Drosera is, perhaps, connected
with this power, for we have seen that the fluids in which they were
immersed often became pink, and the glands pale-coloured or white. Many
of the poisonous acids, such as hydriodic, benzoic, hippuric, and
carbolic (but I neglected to record all the cases), caused the
secretion of an extraordinary amount of mucus, so that long ropes of
this matter hung from the leaves when they were lifted out of the
solutions. Other acids, such as hydrochloric and malic, have no such
ten-

* Miller's 'Elements of Chemistry,' part i. 1867, p. 87.  [page 198]

dency; in these two latter cases the surrounding fluid was not coloured
pink, and the leaves were not poisoned. On the other hand, propionic
acid, which is poisonous, does not cause much mucus to be secreted, yet
the surrounding fluid became slightly pink. Lastly, as in the case of
saline solutions, leaves, after being immersed in certain acids, were
soon acted on by phosphate of ammonia; on the other hand, they were not
thus affected after immersion in certain other acids. To this subject,
however, I shall have to recur.  [page 199]


                          CHAPTER IX.

 THE EFFECTS OF CERTAIN ALKALOID POISONS, OTHER SUBSTANCES AND
                            VAPOURS.

Strychnine, salts of--Quinine, sulphate of, does not soon arrest the
movement of the protoplasm--Other salts of
quinine--Digitaline--Nicotine--Atropine--Veratrine--Colchicine--
Theine--Curare--Morphia--Hyoscyamus--Poison of the cobra, apparently
accelerates the movements of the protoplasm--Camphor, a powerful
stimulant, its vapour narcotic--Certain essential oils excite
movement--Glycerine--Water and certain solutions retard or prevent the
subsequent action of phosphate of ammonia--Alcohol innocuous, its
vapour narcotic and poisonous--Chloroform, sulphuric and nitric ether,
their stimulant, poisonous, and narcotic power--Carbonic acid narcotic,
not quickly poisonous--Concluding remarks.

AS in the last chapter, I will first give my experiments, and then a
brief summary of the results with some concluding remarks.

[Acetate of Strychnine.--Half-minims of a solution of one part to 437
of water were placed on the discs of six leaves; so that each received
1/960 of a grain, or .0675 mg. In 2 hrs. 30 m. the outer tentacles on
some of them were inflected, but in an irregular manner, sometimes only
on one side of the leaf. The next morning, after 22 hrs. 30 m. the
inflection had not increased. The glands on the central disc were
blackened, and had ceased secreting. After an additional 24 hrs. all
the central glands seemed dead, but the inflected tentacles had
re-expanded and appeared quite healthy. Hence the poisonous action of
strychnine seems confined to the glands which have absorbed it;
nevertheless, these glands transmit a motor impulse to the exterior
tentacles. Minute drops (about 1/20 of a minim) of the same solution
applied to the glands of the outer tentacles occasionally caused them
to bend. The poison does not seem to act quickly, for having applied to
several glands similar drops of a rather stronger solution, of one part
to 292 of water, this did not prevent the tentacles bending, when their
glands [page 200] were excited, after an interval of a quarter to three
quarters of an hour, by being rubbed or given bits of meat. Similar
drops of a solution of one part to 218 of water (2 grs. to 1 oz.)
quickly blackened the glands; some few tentacles thus treated moved,
whilst others did not.  The latter, however, on being subsequently
moistened with saliva or given bits of meat, became incurved, though
with extreme slowness; and this shows that they had been injured.
Stronger solutions (but the strength was not ascertained) sometimes
arrested all power of movement very quickly; thus bits of meat were
placed on the glands of several exterior tentacles, and as soon as they
began to move, minute drops of the strong solution were added.  They
continued for a short time to go on bending, and then suddenly stood
still; other tentacles on the same leaves, with meat on their glands,
but not wetted with the strychnine, continued to bend and soon reached
the centre of the leaf.

Citrate of Strychnine.--Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves; after 24 hrs. the outer
tentacles showed only a trace of inflection. Bits of meat were then
placed on three of these leaves, but in 24 hrs. only slight and
irregular inflection occurred, proving that the leaves had been greatly
injured. Two of the leaves to which meat had not been given had their
discal glands dry and much injured. Minute drops of a strong solution
of one part to 109 of water (4 grs. to 1 oz.) were added to the
secretion round several glands, but did not produce nearly so plain an
effect as the drops of a much weaker solution of the acetate. Particles
of the dry citrate were placed on six glands; two of these moved some
way towards the centre, and then stood still, being no doubt killed;
three others curved much farther inwards, and were then fixed; one
alone reached the centre. Five leaves were immersed, each in thirty
minims of a solution of one part to 437 of water; so that each received
1/16 of a grain; after about 1 hr. some of the outer tentacles became
inflected, and the glands were oddly mottled with black and white.
These glands, in from 4 hrs. to 5 hrs., became whitish and opaque, and
the protoplasm in the cells of the tentacles was well aggregated. By
this time two of the leaves were greatly inflected, but the three
others not much more inflected than they were before. Nevertheless two
fresh leaves, after an immersion respectively for 2 hrs. and 4 hrs. in
the solution, were not killed; for on being left for 1 hr. 30 m. in a
solution of one part of carbonate of ammonia to 218 of water, their
tentacles became more inflected, and there was much aggregation. The
glands [page 201] of two other leaves, after an immersion for 2 hrs. in
a stronger solution, of one part of the citrate to 218 of water, became
of an opaque, pale pink colour, which before long disappeared, leaving
them white. One of these two leaves had its blade and tentacles greatly
inflected; the other hardly at all; but the protoplasm in the cells of
both was aggregated down to the bases of the tentacles, with the
spherical masses in the cells close beneath the glands blackened. After
24 hrs. one of these leaves was colourless, and evidently dead.

Sulphate of Quinine.--Some of this salt was added to water, which is
said to dissolve 1/1000 part of its weight. Five leaves were immersed,
each in thirty minims of this solution, which tasted bitter. In less
than 1 hr. some of them had a few tentacles inflected. In 3 hrs. most
of the glands became whitish, others dark-coloured, and many oddly
mottled. After 6 hrs. two of the leaves had a good many tentacles
inflected, but this very moderate degree of inflection never increased.
One of the leaves was taken out of the solution after 4 hrs., and
placed in water; by the next morning some few of the inflected
tentacles had re-expanded, showing that they were not dead; but the
glands were still much discoloured. Another leaf not included in the
above lot, after an immersion of 3 hrs. 15 m., was carefully examined;
the protoplasm in the cells of the outer tentacles, and of the short
green ones on the disc, had become strongly aggregated down to their
bases; and I distinctly saw that the little masses changed their
positions and shapes rather rapidly; some coalescing and again
separating. I was surprised at this fact, because quinine is said to
arrest all movement in the white corpuscles of the blood; but as,
according to Binz,* this is due to their being no longer supplied with
oxygen by the red corpuscles, any such arrestment of movement could not
be expected in Drosera. That the glands had absorbed some of the salt
was evident from their change of colour; but I at first thought that
the solution might not have travelled down the cells of the tentacles,
where the protoplasm was seen in active movement. This view, however, I
have no doubt, is erroneous, for a leaf which had been immersed for 3
hrs. in the quinine solution was then placed in a little solution of
one part of carbonate of ammonia to 218 of water; and in 30 m. the
glands and the upper cells of the tentacles became intensely black,
with the protoplasm presenting a very unusual appearance; for it

* 'Quarterly Journal of Microscopical Science,' April 1874, p. 185.
[page 202]

had become aggregated into reticulated dingy-coloured masses, having
rounded and angular interspaces. As I have never seen this effect
produced by the carbonate of ammonia alone, it must be attributed to
the previous action of the quinine. These reticulated masses were
watched for some time, but did not change their forms; so that the
protoplasm no doubt had been killed by the combined action of the two
salts, though exposed to them for only a short time.

Another leaf, after an immersion for 24 hrs. in the quinine solution,
became somewhat flaccid, and the protoplasm in all the cells was
aggregated. Many of the aggregated masses were discoloured, and
presented a granular appearance; they were spherical, or elongated, or
still more commonly consisted of little curved chains of small
globules. None of these masses exhibited the least movement, and no
doubt were all dead.

Half-minims of the solution were placed on the discs of six leaves;
after 23 hrs. one had all its tentacles, two had a few, and the others
none inflected; so that the discal glands, when irritated by this salt,
do not transmit any strong motor impulse to the outer tentacles. After
48 hrs. the glands on the discs of all six leaves were evidently much
injured or quite killed. It is clear that this salt is highly
poisonous.*

Acetate of Quinine.--Four leaves were immersed, each in thirty minims
of a solution of one part to 437 of water. The solution was tested with
litmus paper, and was not acid. After only 10 m. all four leaves were
greatly, and after 6 hrs. immensely, inflected. They were then left in
water for 60 hrs., but never re-expanded; the glands were white, and
the leaves evidently dead. This salt is far more efficient than the
sulphate in causing inflection, and, like that salt, is highly
poisonous.

Nitrate of Quinine.--Four leaves were immersed, each in thirty minims
of a solution of one part to 437 of water. After 6 hrs. there was
hardly a trace of inflection; after 22 hrs. three of the leaves were
moderately, and the fourth slightly inflected; so that this salt
induces, though rather slowly, well-marked inflection. These leaves, on
being left in water for 48 hrs., almost

*Binz found several years ago (as stated in 'The Journal of Anatomy and
Phys.' November 1872, p. 195) that quinia is an energetic poison to low
vegetable and animal organisms. Even one part added to 4000 parts of
blood arrests the movements of the white corpuscles, which become
"rounded and granular." In the tentacles of Drosera the aggregated
masses of protoplasm, which appeared killed by the quinine, likewise
presented a granular appearance.  A similar appearance is caused by
very hot water.  [page 203]

completely re-expanded, but the glands were much discoloured. Hence
this salt is not poisonous in any high degree. The different action of
the three foregoing salts of quinine is singular.

Digitaline.--Half-minims of a solution of one part to 437 of water were
placed on the discs of five leaves. In 3 hrs. 45 m. Some of them had
their tentacles, and one had its blade, moderately inflected. After 8
hrs. three of them were well inflected; the fourth had only a few
tentacles inflected, and the fifth (an old leaf) was not at all
affected. They remained in nearly the same state for two days, but the
glands on their discs became pale. On the third day the leaves appeared
much injured. Nevertheless, when bits of meat were placed on two of
them, the outer tentacles became inflected. A minute drop (about 1/20
of a minim) of the solution was applied to three glands, and after 6
hrs. all three tentacles were inflected, but next day had nearly
re-expanded; so that this very small dose of 1/28800 of a grain (.00225
mg.) acts on a tentacle, but is not poisonous. It appears from these
several facts that digitaline causes inflection, and poisons the glands
which absorb a moderately large amount.

Nicotine.--The secretion round several glands was touched with a minute
drop of the pure fluid, and the glands were instantly blackened; the
tentacles becoming inflected in a few minutes. Two leaves were immersed
in a weak solution of two drops to 1 oz., or 437 grains, of water. When
examined after 3 hrs. 20 m., only twenty-one tentacles on one leaf were
closely inflected, and six on the other slightly so; but all the glands
were blackened, or very dark-coloured, with the protoplasm in all the
cells of all the tentacles much aggregated and dark-coloured. The
leaves were not quite killed, for on being placed in a little solution
of carbonate of ammonia (2 grs. to 1 oz.) a few more tentacles became
inflected, the remainder not being acted on during the next 24 hrs.

Half-minims of a stronger solution (two drops to 1/2 oz. of water) were
placed on the discs of six leaves, and in 30 m. all those tentacles
became inflected; the glands of which had actually touched the
solution, as shown by their blackness; but hardly any motor influence
was transmitted to the outer tentacles. After 22 hrs. most of the
glands on the discs appeared dead; but this could not have been the
case, as when bits of meat were placed on three of them, some few of
the outer tentacles were inflected in 24 hrs. Hence nicotine has a
great tendency to blacken the glands and to induce aggregation [page
204] of the protoplasm, but, except when pure, has very moderate power
of inducing inflection, and still less power of causing a motor
influence to be transmitted from the discal glands to the outer
tentacles. It is moderately poisonous.

Atropine.--A grain was added to 437 grains of water, but was not all
dissolved; another grain was added to 437 grains of a mixture of one
part of alcohol to seven parts of water; and a third solution was made
by adding one part of valerianate of atropine to 437 of water.
Half-minims of these three solutions were placed, in each case, on the
discs of six leaves; but no effect whatever was produced, excepting
that the glands on the discs to which the valerianate was given were
slightly discoloured. The six leaves on which drops of the solution of
atropine in diluted alcohol had been left for 21 hrs. were given bits
of meat, and all became in 24 hrs. fairly well inflected; so that
atropine does not excite movement, and is not poisonous. I also tried
in the same manner the alkaloid sold as daturine, which is believed not
to differ from atropine, and it produced no effect. Three of the leaves
on which drops of this latter solution had been left for 24 hrs. were
likewise given bits of meat, and they had in the course of 24 hrs. a
good many of their submarginal tentacles inflected.

Veratrine, Colchicine, Theine.--Solutions were made of these three
alkaloids by adding one part to 437 of water. Half-minims were placed,
in each case; on the discs of at least six leaves, but no inflection
was caused, except perhaps a very slight amount by the theine.
Half-minims of a strong infusion of tea likewise produced, as formerly
stated, no effect. I also tried similar drops of an infusion of one
part of the extract of colchicum, sold by druggists, to 218 of water;
and the leaves were observed for 48 hrs., without any effect being
produced. The seven leaves on which drops of veratrine had been left
for 26 hrs. were given bits of meat, and after 21 hrs. were well
inflected. These three alkaloids are therefore quite innocuous.

Curare.--One part of this famous poison was added to 218 of water, and
three leaves were immersed in ninety minims of the filtered solution.
In 3 hrs. 30 m. some of the tentacles were a little inflected; as was
the blade of one; after 4 hrs. After 7 hrs. the glands were wonderfully
blackened, showing that matter of some kind had been absorbed. In 9
hrs. two of the leaves had most of their tentacles sub-inflected, but
the inflection did not increase in the course of 24 hrs. One of these
leaves, after being immersed for 9 hrs. in the solution, was placed in
water, and by next morning had largely re-expanded; [page 205] the
other two, after their immersion for 24 hrs., were likewise placed in
water, and in 24 hrs.  were considerably re-expanded, though their
glands were as black as ever. Half-minims were placed on the discs of
six leaves, and no inflection ensued; but after three days the glands
on the discs appeared rather dry, yet to my surprise were not
blackened. On another occasion drops were placed on the discs of six
leaves, and a considerable amount of inflection was soon caused; but as
I had not filtered the solution, floating particles may have acted on
the glands. After 24 hrs. bits of meat were placed on the discs of
three of these leaves, and next day they became strongly inflected. As
I at first thought that the poison might not have been dissolved in
pure water, one grain was added to 437 grains of a mixture of one part
of alcohol to seven of water, and half-minims were placed on the discs
of six leaves. These were not at all affected, and when after a day
bits of meat were given them, they were slightly inflected in 5 hrs.,
and closely after 24 hrs. It follows from these several facts that a
solution of curare induces a very moderate degree of inflection, and
this may perhaps be due to the presence of a minute quantity of
albumen. It certainly is not poisonous. The protoplasm in one of the
leaves, which had been immersed for 24 hrs., and which had become
slightly inflected, had undergone a very slight amount of
aggregation--not more than often ensues from an immersion of this
length of time in water.

Acetate of Morphia.--I tried a great number of experiments with this
substance, but with no certain result. A considerable number of leaves
were immersed from between 2 hrs. and 6 hrs. in a solution of one part
to 218 of water, and did not become inflected. Nor were they poisoned;
for when they were washed and placed in weak solutions of phosphate and
carbonate of ammonia, they soon became strongly inflected, with the
protoplasm in the cells well aggregated. If, however, whilst the leaves
were immersed in the morphia, phosphate of ammonia was added,
inflection did not rapidly ensue. Minute drops of the solution were
applied in the usual manner to the secretion round between thirty and
forty glands; and when, after an interval of 6 m:, bits of meat, a
little saliva, or particles of glass, were placed on them, the movement
of the tentacles was greatly retarded. But on other occasions no such
retardation occurred. Drops of water similarly applied never have any
retarding power.  Minute drops of a solution of sugar of the same
strength (one part to 218 of water) sometimes retarded the subsequent
action of meat and of particles of glass, and [page 206] sometimes did
not do so. At one time I felt convinced that morphia acted as a
narcotic on Drosera, but after having found in what a singular manner
immersion in certain non-poisonous salts and acids prevents the
subsequent action of phosphate of ammonia, whereas other solutions have
no such power, my first conviction seems very doubtful.

Extract of Hyoscyamus.--Several leaves were placed, each in thirty
minims of an infusion of 3 grs. of the extract sold by druggists to 1
oz. of water. One of them, after being immersed for 5 hrs. 15 m., was
not inflected, and was then put into a solution (1 gr. to 1 oz.) of
carbonate of ammonia; after 2 hrs. 40 m. it was found considerably
inflected, and the glands much blackened. Four of the leaves, after
being immersed for 2 hrs. 14 m., were placed in 120 minims of a
solution (1 gr. to 20 oz.) of phosphate of ammonia; they had already
become slightly inflected from the hyoscyamus, probably owing to the
presence of some albuminous matter, as formerly explained, but the
inflection immediately increased, and after 1 hr. was strongly
pronounced; so that hyoscyamus does not act as a narcotic or poison.

Poison from the Fang of a Living Adder.--Minute drops were placed on
the glands of many tentacles; these were quickly inflected, just as if
saliva had been given them, Next morning, after 17 hrs. 30 m., all were
beginning to re-expand, and they appeared uninjured.

Poison from the Cobra.--Dr. Fayrer, well known from his investigations
on the poison of this deadly snake, was so kind as to give me some in a
dried state. It is an albuminous substance, and is believed to replace
the ptyaline of saliva.* A minute drop (about 1/20 of a minim) of a
solution of one part to 437 of water was applied to the secretion round
four glands; so that each received only about 1/38400 of a grain (.0016
mg.). The operation was repeated on four other glands; and in 15 m.
several of the eight tentacles became well inflected, and all of them
in 2 hrs. Next morning, after 24 hrs., they were still inflected, and
the glands of a very pale pink colour. After an additional 24 hrs. they
were nearly re-expanded, and completely so on the succeeding day; but
most of the glands remained almost white.

Half-minims of the same solution were placed on the discs of three
leaves, so that each received 1/960 of a grain (.0675 mg.); in

*Dr. Fayrer, 'The Thanatophidia of India,' 1872, p. 150.  [page 207]

4 hrs. 15 m. the outer tentacles were much inflected; and after 6 hrs.
30 m. those on two of the leaves were closely inflected and the blade
of one; the third leaf was only moderately affected. The leaves
remained in the same state during the next day, but after 48 hrs.
re-expanded.

Three leaves were now immersed, each in thirty minims of the solution,
so that each received 1/16 of a grain, or 4.048 mg. In 6 m. there was
some inflection, which steadily increased, so that after 2 hrs. 30 m.
all three leaves were closely inflected; the glands were at first
somewhat darkened, then rendered pale; and the protoplasm within the
cells of the tentacles was partially aggregated. The little masses of
protoplasm were examined after 3 hrs., and again after 7 hrs., and on
no other occasion have I seen them undergoing such rapid changes of
form. After 8 hrs. 30 m. the glands had become quite white; they had
not secreted any great quantity of mucus. The leaves were now placed in
water, and after 40 hrs. re-expanded, showing that they were not much
or at all injured. During their immersion in water the protoplasm
within the cells of the tentacles was occasionally examined, and always
found in strong movement.

Two leaves were next immersed, each in thirty minims of a much stronger
solution, of one part to 109 of water; so that each received 1/4 of a
grain, or 16.2 mg; After 1 hr. 45 m. the sub-marginal tentacles were
strongly inflected, with the glands somewhat pale; after 3 hrs. 30 m.
both leaves had all their tentacles closely inflected and the glands
white. Hence the weaker solution, as in so many other cases, induced
more rapid inflection than the stronger one; but the glands were sooner
rendered white by the latter. After an immersion of 24 hrs.  some of
the tentacles were examined, and the protoplasm, still of a fine purple
colour, was found aggregated into chains of small globular masses.
These changed their shapes with remarkable quickness. After an
immersion of 48 hrs. they were again examined, and their movements were
so plain that they could easily be seen under a weak power. The leaves
were now placed in water, and after 24 hrs. (i.e. 72 hrs. from their
first immersion) the little masses of protoplasm, which had become of a
dingy purple, were still in strong movement, changing their shapes,
coalescing, and again separating.

In 8 hrs. after these two leaves had been placed in water (i.e. in 56
hrs. after their immersion in the solution) they began to re-expand,
and by the next morning were more expanded. After an additional day
(i.e. on the fourth day after their immersion in the solution) they
were largely, but not quite fully [page 208] expanded. The tentacles
were now examined, and the aggregated masses were almost wholly
redissolved; the cells being filled with homogeneous purple fluid, with
the exception here and there of a single globular mass. We thus see how
completely the protoplasm had escaped all injury from the poison. As
the glands were soon rendered quite white, it occurred to me that their
texture might have been modified in such a manner as to prevent the
poison passing into the cells beneath, and consequently that the
protoplasm within these cells had not been at all affected. Accordingly
I placed another leaf, which had been immersed for 48 hrs. in the
poison and afterwards for 24 hrs. in water, in a little solution of one
part of carbonate of ammonia to 218 of water; in 30 m. the protoplasm
in the cells beneath the glands became darker, and in the course of 24
hrs. the tentacles were filled down to their bases with dark-coloured
spherical masses. Hence the glands had not lost their power of
absorption, as far as the carbonate of ammonia is concerned.

From these facts it is manifest that the poison of the cobra, though so
deadly to animals, is not at all poisonous to Drosera; yet it causes
strong and rapid inflection of the tentacles, and soon discharges all
colour from the glands. It seems even to act as a stimulant to the
protoplasm, for after considerable experience in observing the
movements of this substance in Drosera, I have never seen it on any
other occasion in so active a state. I was therefore anxious to learn
how this poison affected animal protoplasm; and Dr. Fayrer was so kind
as to make some observations for me, which he has since published.*
Ciliated epithelium from the mouth of a frog was placed in a solution
of .03 gramme to 4.6 cubic cm. of water; others being placed at the
same time in pure water for comparison. The movements of the cilia in
the solution seemed at first increased, but soon languished, and after
between 15 and 20 minutes ceased; whilst those in the water were still
acting vigorously. The white corpuscles of the blood of a frog, and the
cilia on two infusorial animals, a Paramaecium and Volvox, were
similarly affected by the poison. Dr. Fayrer also found that the muscle
of a frog lost its irritability after an immersion of 20 m. in the
solution, not then responding to a strong electrical current. On the
other hand, the movements of the cilia on the mantle of an Unio were
not always arrested, even when left for a consider-

* 'Proceedings of Royal Society,' Feb. 18, 1875.  [page 209]

able time in a very strong solution. On the whole, it seems that the
poison of the cobra acts far more injuriously on the protoplasm of the
higher animals than on that of Drosera.

There is one other point which may be noticed. I have occasionally
observed that the drops of secretion round the glands were rendered
somewhat turbid by certain solutions, and more especially by some
acids, a film being formed on the surfaces of the drops; but I never
saw this effect produced in so conspicuous a manner as by the cobra
poison. When the stronger solution was employed, the drops appeared in
10 m. like little white rounded clouds. After 48 hrs. the secretion was
changed into threads and sheets of a membranous substance, including
minute granules of various sizes.

Camphor.--Some scraped camphor was left for a day in a bottle with
distilled water, and then filtered. A solution thus made is said to
contain 1/1000 of its weight of camphor; it smelt and tasted of this
substance. Ten leaves were immersed in this solution; after 15 m. five
of them were well inflected, two showing a first trace of movement in
11 m. and 12 m.; the sixth leaf did not begin to move until 15 m. had
elapsed, but was fairly well inflected in 17 m. and quite closed in 24
m.; the seventh began to move in 17 m., and was completely shut in 26
m.  The eighth, ninth, and tenth leaves were old and of a very dark red
colour, and these were not inflected after an immersion of 24 hrs.; so
that in making experiments with camphor it is necessary to avoid such
leaves. Some of these leaves, on being left in the solution for 4 hrs.,
became of a rather dingy pink colour, and secreted much mucus; although
their tentacles were closely inflected, the protoplasm within the cells
was not at all aggregated. On another occasion, however, after a longer
immersion of 24 hrs., there was well marked aggregation.  A solution
made by adding two drops of camphorated spirits to an ounce of water
did not act on one leaf; whereas thirty minims added to an ounce of
water acted on two leaves immersed together.

M. Vogel has shown* that the flowers of various plants do not wither so
soon when their stems are placed in a solution of camphor as when in
water; and that if already slightly withered, they recover more
quickly. The germination of certain seeds is also accelerated by the
solution. So that camphor acts as a stimulant, and it is the only known
stimulant for plants. I

* 'Gardener's Chronicle,' 1874, p. 671. Nearly similar observations
were made in 1798 by B.  S. Barton.  [page 210]

wished, therefore, to ascertain whether camphor would render the leaves
of Drosera more sensitive to mechanical irritation than they naturally
are. Six leaves were left in distilled water for 5 m. or 6 m., and then
gently brushed twice or thrice, whilst still under water, with a soft
camel-hair brush; but no movement ensued. Nine leaves, which had been
immersed in the above solution of camphor for the times stated in the
following table, were next brushed only once with the same brush and in
the same manner as before; the results are given in the table. My first
trials were made by brushing the leaves whilst still immersed in the
solution; but it occurred to me that the viscid secretion round the
glands would thus be removed, and the camphor might act more
effectually on them. In all the following trials, therefore, each leaf
was taken out of the solution, waved for about 15 s. in water, then
placed in fresh water and brushed, so that the brushing would not allow
the freer access of the camphor; but this treatment made no difference
in the results.

Column 1 : Number of Leaves.  Column 2 : Length of Immersion in the
Solution of Camphor.  Column 3 : Length of Time between the Act of
Brushing and the Inflection of the Tentacles.  Column 4 : Length of
Time between the Immersion of the Leaves in the Solution and the First
Sign of the Inflection of the Tentacles.

1 : 5 m. : 3 m. considerable inflection; 4 m. all the tentacles except
3 or 4 inflected. : 8 m.

2 : 5 m. : 6 m. first sign of inflection. : 11 m.

3 : 5 m. : 6 m. 30 s. slight inflection; 7 m. 30 s. plain inflection. :
11 m. 30 s.

4 : 4 m. 30 s. : 2 m. 30 s. a trace of inflection; 3 m. plain; 4 m.
strongly marked. : 7 m.

5 : 4 m. : 2 m. 30 s. a trace of inflection; 3 m. plain inflection. : 6
m. 30 s.

6 : 4 m. : 2 m. 30 s. decided inflection; 3 m. 30 s. strongly marked. :
6 m. 30 s.

7 : 4 m. : 2 m. 30 s. slight inflection; 3 m. plain; 4 m. well marked.
: 6 m. 30 s.

8 : 3 m. : 2 m. trace of inflection; 3 m. considerable, 6 m. strong
inflection. : 5 m.

9 : 3 m. : 2 m. trace of inflection; 3 m. considerable, 6 m. strong
inflection. : 5 m.

Other leaves were left in the solution without being brushed; one of
these first showed a trace of inflection after 11 m.; a second after 12
m.; five were not inflected until 15 m. had [page 211] elapsed, and two
not until a few minutes later. On the other hand, it will be seen in
the right-hand column of the table that most of the leaves subjected to
the solution, and which were brushed, became inflected in a much
shorter time. The movement of the tentacles of some of these leaves was
so rapid that it could be plainly seen through a very weak lens.

Two or three other experiments are worth giving. A large old leaf,
after being immersed for 10 m. in the solution, did not appear likely
to be soon inflected; so I brushed it, and in 2 m. it began to move,
and in 3 m. was completely shut. Another leaf, after an immersion of 15
m., showed no signs of inflection, so was brushed, and in 4 m. was
grandly inflected. A third leaf, after an immersion of 17 m., likewise
showed no signs of inflection; it was then brushed, but did not move
for 1 hr.; so that here was a failure. It was again brushed, and now in
9 m. a few tentacles became inflected; the failure therefore was not
complete.

We may conclude that a small dose of camphor in solution is a powerful
stimulant to Drosera. It not only soon excites the tentacles to bend,
but apparently renders the glands sensitive to a touch, which by itself
does not cause any movement. Or it may be that a slight mechanical
irritation not enough to cause any inflection yet gives some tendency
to movement, and thus reinforces the action of the camphor. This latter
view would have appeared to me the more probable one, had it not been
shown by M. Vogel that camphor is a stimulant in other ways to various
plants and seeds.

Two plants bearing four or five leaves, and with their roots in a
little cup of water, were exposed to the vapour of some bits of camphor
(about as large as a filbert-nut), under a vessel holding ten fluid oz.
After 10 hrs. no inflection ensued; but the glands appeared to be
secreting more copiously. The leaves were in a narcotised condition,
for on bits of meat being placed on two of them, there was no
inflection in 3 hrs. 15 m., and even after 13 hrs. 15 m. only a few of
the outer tentacles were slightly inflected; but this degree of
movement shows that the leaves had not been killed by an exposure
during 10 hrs. to the vapour of camphor.

Oil of Caraway.--Water is said to dissolve about a thousandth part of
its weight of this oil. A drop was added to an ounce of water and the
bottle occasionally shaken during a day; but many minute globules
remained undissolved. Five leaves were immersed in this mixture; in
from 4 m. to 5 m. there was some inflection, which became moderately
pronounced in two or [page 212] three additional minutes. After 14 m.
all five leaves were well, and some of them closely, inflected. After 6
hrs. the glands were white, and much mucus had been secreted. The
leaves were now flaccid, of a peculiar dull-red colour, and evidently
dead. One of the leaves, after an immersion of 4 m., was brushed, like
the leaves in the camphor, but this produced no effect. A plant with
its roots in water was exposed under a 10-oz. vessel to the vapour of
this oil, and in 1 hr. 20 m. one leaf showed a trace of inflection.
After 5 hrs. 20 m. the cover was taken off and the leaves examined; one
had all its tentacles closely inflected, the second about half in the
same state; and the third all sub-inflected. The plant was left in the
open air for 42 hrs., but not a single tentacle expanded; all the
glands appeared dead, except here and there one, which was still
secreting. It is evident that this oil is highly exciting and poisonous
to Drosera.

Oil of Cloves.--A mixture was made in the same manner as in the last
case, and three leaves were immersed in it. After 30 m. there was only
a trace of inflection which never increased.  After 1 hr. 30 m. the
glands were pale, and after 6 hrs. white. No doubt the leaves were much
injured or killed.

Turpentine.--Small drops placed on the discs of some leaves killed
them, as did likewise drops of creosote. A plant was left for 15 m.
under a 12-oz. vessel, with its inner surface wetted with twelve drops
of turpentine; but no movement of the tentacles ensued. After 24 hrs.
the plant was dead.

Glycerine.--Half-minims were placed on the discs of three leaves: in 2
hrs. some of the outer tentacles were irregularly inflected; and in 19
hrs. the leaves were flaccid and apparently dead; the glands which had
touched the glycerine were colourless. Minute drops (about 1/20 of a
minim) were applied to the glands of several tentacles, and in a few
minutes these moved and soon reached the centre. Similar drops of a
mixture of four dropped drops to 1 oz.  of water were likewise applied
to several glands; but only a few of the tentacles moved, and these
very slowly and slightly. Half-minims of this same mixture placed on
the discs of some leaves caused, to my surprise, no inflection in the
course of 48 hrs. Bits of meat were then given them, and next day they
were well inflected; notwithstanding that some of the discal glands had
been rendered almost colourless. Two leaves were immersed in the same
mixture, but only for 4 hrs.; they were not inflected, and on being
afterwards left for 2 hrs. 30 m. in a solution (1 gr. to 1 oz.) of
carbonate of ammonia, their glands were blackened, their tentacles
inflected, and the protoplasm within their cells aggregated. It appears
[page 213] from these facts that a mixture of four drops of glycerine
to an ounce of water is not poisonous, and excites very little
inflection; but that pure glycerine is poisonous, and if applied in
very minute quantities to the glands of the outer tentacles causes
their inflection.

The Effects of Immersion in Water and in various Solutions on the
subsequent Action of Phosphate and Carbonate of Ammonia.--We have seen
in the third and seventh chapters that immersion in distilled water
causes after a time some degree of aggregation of the protoplasm, and a
moderate amount of inflection, especially in the case of plants which
have been kept at a rather high temperature. Water does not excite a
copious secretion of mucus.  We have here to consider the effects of
immersion in various fluids on the subsequent action of salts of
ammonia and other stimulants. Four leaves which had been left for 24
hrs. in water were given bits of meat, but did not clasp them. Ten
leaves, after a similar immersion, were left for 24 hrs. in a powerful
solution (1 gr. to 20 oz.) of phosphate of ammonia, and only one showed
even a trace of inflection. Three of these leaves, on being left for an
additional day in the solution, still remained quite unaffected. When,
however, some of these leaves, which had been first immersed in water
for 24 hrs., and then in the phosphate for 24 hrs. were placed in a
solution of carbonate of ammonia (one part to 218 of water), the
protoplasm in the cells of the tentacles became in a few hours strongly
aggregated, showing that this salt had been absorbed and taken effect.

A short immersion in water for 20 m. did not retard the subsequent
action of the phosphate, or of splinters of glass placed on the glands;
but in two instances an immersion for 50 m.  prevented any effect from
a solution of camphor. Several leaves which had been left for 20 m. in
a solution of one part of white sugar to 218 of water were placed in
the phosphate solution, the action of which was delayed; whereas a
mixed solution of sugar and the phosphate did not in the least
interfere with the effects of the latter. Three leaves, after being
immersed for 20 m. in the sugar solution, were placed in a solution of
carbonate of ammonia (one part to 218 of water); in 2 m. or 3 m. the
glands were blackened, and after 7 m. the tentacles were considerably
inflected, so that the solution of sugar, though it delayed the action
of the phosphate, did not delay that of the carbonate. Immersion in a
similar solution of gum arabic for 20 m. had no retarding action on the
phosphate. Three leaves were left for 20 m. in a mixture of one part of
alcohol to seven parts of water, [page 214] and then placed in the
phosphate solution: in 2 hrs. 15 m. there was a trace of inflection in
one leaf, and in 5 hrs. 30 m. a second was slightly affected; the
inflection subsequently increased, though slowly. Hence diluted
alcohol, which, as we shall see, is hardly at all poisonous, plainly
retards the subsequent action of the phosphate.

It was shown in the last chapter that leaves which did not become
inflected by nearly a day's immersion in solutions of various salts and
acids behaved very differently from one another when subsequently
placed in the phosphate solution. I here give a table summing up the
results.

Column 1 : Name of the Salts and Acids in Solution.  Column 2 : Period
of Immersion of the Leaves in Solutions of one part to 437 of water.
Column 3 : Effects produced on the Leaves by their subsequent Immersion
for stated periods in a Solution of one part of phosphate of ammonia to
8750 of water, or 1 gr. to 20 oz.

Rubidium chloride. : 22 hrs. : After 30 m. strong inflection of the
tentacles.

Potassium carbonate : 20 m. : Scarcely any inflection until 5 hrs. had
elapsed.

Calcium acetate. : 24 hrs. : After 24 hrs. very slight inflection.

Calcium nitrate. : 24 hrs. : Do. do.

Magnesium acetate. : 22 hrs. : Some slight inflection, which became
well pronounced in 24 hrs.

Magnesium nitrate. : 22 hrs. : After 4 hrs. 30 m. a fair amount of
inflection, which never increased.

Magnesium chloride : 22 hrs. : After a few minutes great inflection;
after 4 hrs. all four leaves with almost every tentacle closely
inflected.

Barium acetate. : 22 hrs. : After 24 hrs. two leaves out of four
slightly inflected.

Barium nitrate. : 22 hrs. : After 30 m. one leaf greatly, and two
others moderately, inflected; they remained thus for 24 hrs.

Strontium acetate. : 22 hrs. : After 25 m. two leaves greatly
inflected; after 8 hrs. a third leaf moderately, and the fourth very
slightly, inflected. All four thus remained for 24 hrs.

Strontium nitrate. : 22 hrs. : After 8 hrs. three leaves out of five
moderately inflected; after 24 hrs. all five in this state; but not one
closely inflected.

Aluminium chloride : 24 hrs. : Three leaves which had either been
slightly or not at all affected by the chloride became after 7 hrs. 30
m. rather closely inflected.  [page 215]

Column 1 : Name of the Salts and Acids in Solution.  Column 2 : Period
of Immersion of the Leaves in Solutions of one part to 437 of water.
Column 3 : Effects produced on the Leaves by their subsequent Immersion
for stated periods in a Solution of one part of phosphate of ammonia to
8750 of water, or 1 gr. to 20 oz.

Aluminium nitrate. : 24 hrs. : After 25 hrs. slight and doubtful
effect.

Lead chloride. : 23 hrs. : After 24 hrs. two leaves somewhat inflected,
the third very little; and thus remained.

Manganese chloride : 22 hrs. : After 48 hrs. not the least inflection.

Lactic acid. : 48 hrs. : After 24 hrs. a trace of inflection in a few
tentacles, the glands of which had not been killed by the acid.

Tannic acid. : 24 hrs. : After 24 hrs. no inflection.

Tartaric acid. : 24 hrs. : Do. do.

Citric acid. : 24 hrs. : After 50 m. tentacles decidedly inflected, and
after 5 hrs. strongly inflected; so remained for the next 24 hrs.

Formic acid. : 22 hrs. : Not observed until 24 hrs. had elapsed;
tentacles considerably inflected, and protoplasm aggregated.

In a large majority of these twenty cases, a varying degree of
inflection was slowly caused by the phosphate. In four cases, however,
the inflection was rapid, occurring in less than half an hour or at
most in 50 m. In three cases the phosphate did not produce the least
effect. Now what are we to infer from these facts? We know from ten
trials that immersion in distilled water for 24 hrs. prevents the
subsequent action of the phosphate solution. It would, therefore,
appear as if the solutions of chloride of manganese, tannic and
tartaric acids, which are not poisonous, acted exactly like water, for
the phosphate produced no effect on the leaves which had been
previously immersed in these three solutions. The majority of the other
solutions behaved to a certain extent like water, for the phosphate
produced, after a considerable interval of time, only a slight effect.
On the other hand, the leaves which had been immersed in the solutions
of the chloride of rubidium and magnesium, of acetate of strontium,
nitrate of barium, and citric acid, were quickly acted on by the
phosphate. Now was water absorbed from these five weak solutions, and
yet, owing to the presence of the salts, did not prevent the subsequent
action of the phosphate? Or [page 216] may we not suppose* that the
interstices of the walls of the glands were blocked up with the
molecules of these five substances, so that they were rendered
impermeable to water; for had water entered, we know from the ten
trials that the phosphate would not afterwards have produced any
effect? It further appears that the molecules of the carbonate of
ammonia can quickly pass into glands which, from having been immersed
for 20 m. in a weak solution of sugar, either absorb the phosphate very
slowly or are acted on by it very slowly. On the other hand, glands,
however they may have been treated, seem easily to permit the
subsequent entrance of the molecules of carbonate of ammonia. Thus
leaves which had been immersed in a solution (of one part to 437 of
water) of nitrate of potassium for 48 hrs.--of sulphate of potassium
for 24 hrs.--and of the chloride of potassium for 25 hrs.--on being
placed in a solution of one part of carbonate of ammonia to 218 of
water, had their glands immediately blackened, and after 1 hr. their
tentacles somewhat inflected, and the protoplasm aggregated.  But it
would be an endless task to endeavour to ascertain the wonderfully
diversified effects of various solutions on Drosera.

Alcohol (one part to seven of water).--It has already been shown that
half-minims of this strength placed on the discs of leaves do not cause
any inflection; and that when two days afterwards the leaves were given
bits of meat, they became strongly inflected. Four leaves were immersed
in this mixture, and two of them after 30 m. were brushed with a
camel-hair brush, like the leaves in the solution of camphor, but this
produced no effect.

* See Dr. M. Traube's curious experiments on the production of
artificial cells, and on their permeability to various salts, described
in his papers: "Experimente zur Theorie der Zellenbildung und
Endosmose," Breslau, 1866; and "Experimente zur physicalischen Erklrung
der Bildung der Zellhaut, ihres Wachsthums durch Intussusception,"
Breslau, 1874. These researches perhaps explain my results. Dr. Traube
commonly employed as a membrane the precipitate formed when tannic acid
comes into contact with a solution of gelatine. By allowing a
precipitation of sulphate of barium to take place at the same time, the
membrane becomes "infiltrated" with this salt; and in consequence of
the intercalation of molecules of sulphate of barium among those of the
gelatine precipitate, the molecular interstices in the membrane are
made smaller. In this altered condition, the membrane no longer allows
the passage through it of either sulphate of ammonia or nitrate of
barium, though it retains its permeability for water and chloride of
ammonia.  [page 217]

Nor did these four leaves, on being left for 24 hrs. in the diluted
alcohol, undergo any inflection. They were then removed; one being
placed in an infusion of raw meat, and bits of meat on the discs of the
other three, with their stalks in water. Next day one seemed a little
injured, whilst two others showed merely a trace of inflection. We
must, however, bear in mind that immersion for 24 hrs. in water
prevents leaves from clasping meat. Hence alcohol of the above strength
is not poisonous, nor does it stimulate the leaves like camphor does.

The vapour of alcohol acts differently. A plant having three good
leaves was left for 25 m.  under a receiver holding 19 oz. with sixty
minims of alcohol in a watch-glass. No movement ensued, but some few of
the glands were blackened and shrivelled, whilst many became quite
pale. These were scattered over all the leaves in the most irregular
manner, reminding me of the manner in which the glands were affected by
the vapour of carbonate of ammonia.  Immediately on the removal of the
receiver particles of raw meat were placed on many of the glands, those
which retained their proper colour being chiefly selected. But not a
single tentacle was inflected during the next 4 hrs. After the first 2
hrs. the glands on all the tentacles began to dry; and next morning,
after 22 hrs., all three leaves appeared almost dead, with their glands
dry; the tentacles on one leaf alone being partially inflected.

A second plant was left for only 5 m. with some alcohol in a
watch-glass, under a 12-oz.  receiver, and particles of meat were then
placed on the glands of several tentacles. After 10 m. some of them
began to curve inwards, and after 55 m. nearly all were considerably
inflected; but a few did not move. Some anaesthetic effect is here
probable, but by no means certain. A third plant was also left for 5 m.
under the same small vessel, with its whole inner surface wetted with
about a dozen drops of alcohol. Particles of meat were now placed on
the glands of several tentacles, some of which first began to move in
25 m.; after 40 m. most of them were somewhat inflected, and after 1
hr. 10 m. almost all were considerably inflected.  From their slow rate
of movement there can be no doubt that the glands of these tentacles
had been rendered insensible for a time by exposure during 5 m. to the
vapour of alcohol.

Vapour of Chloroform.--The action of this vapour on Drosera is very
variable, depending, I suppose, on the constitution or age of the
plant, or on some unknown condition. It sometimes causes the tentacles
to move with extraordinary rapidity, and sometimes produces no such
effect. The glands are sometimes [page 218] rendered for a time
insensible to the action of raw meat, but sometimes are not thus
affected, or in a very slight degree. A plant recovers from a small
dose, but is easily killed by a larger one.

A plant was left for 30 m. under a bell-glass holding 19 fluid oz.
(539.6 ml.) with eight drops of chloroform, and before the cover was
removed, most of the tentacles became much inflected, though they did
not reach the centre. After the cover was removed, bits of meat were
placed on the glands of several of the somewhat incurved tentacles;
these glands were found much blackened after 6 hrs. 30 m., but no
further movement ensued. After 24 hrs. the leaves appeared almost
dead.

A smaller bell-glass, holding 12 fluid oz. (340.8 ml.), was now
employed, and a plant was left for 90 s. under it, with only two drops
of chloroform. Immediately on the removal of the glass all the
tentacles curved inwards so as to stand perpendicularly up; and some of
them could actually be seen moving with extraordinary quickness by
little starts, and therefore in an unnatural manner; but they never
reached the centre. After 22 hrs. they fully re-expanded, and on meat
being placed on their glands, or when roughly touched by a needle, they
promptly became inflected; so that these leaves had not been in the
least injured.

Another plant was placed under the same small bell-glass with three
drops of chloroform, and before two minutes had elapsed, the tentacles
began to curl inwards with rapid little jerks. The glass was then
removed, and in the course of two or three additional minutes almost
every tentacle reached the centre. On several other occasions the
vapour did not excite any movement of this kind.

There seems also to be great variability in the degree and manner in
which chloroform renders the glands insensible to the subsequent action
of meat. In the plant last referred to, which had been exposed for 2 m.
to three drops of chloroform, some few tentacles curved up only to a
perpendicular position, and particles of meat were placed on their
glands; this caused them in 5 m. to begin moving, but they moved so
slowly that they did not reach the centre until 1 hr. 30 m. had
elapsed. Another plant was similarly exposed, that is, for 2 m. to
three drops of chloroform, and on particles of meat being placed on the
glands of several tentacles, which had curved up into a perpendicular
position, one of these began to bend in 8 m., but afterwards moved very
slowly; whilst none of the other tentacles [page 219] moved for the
next 40 m. Nevertheless, in 1 hr. 45 m. from the time when the bits of
meat had been given, all the tentacles reached the centre. In this case
some slight anaesthetic effect apparently had been produced. On the
following day the plant had perfectly recovered.

Another plant bearing two leaves was exposed for 2 m. under the 19-oz.
vessel to two drops of chloroform; it was then taken out and examined;
again exposed for 2 m. to two drops; taken out, and re-exposed for 3 m.
to three drops; so that altogether it was exposed alternately to the
air and during 7 m. to the vapour of seven drops of chloroform. Bits of
meat were now placed on thirteen glands on the two leaves. On one of
these leaves, a single tentacle first began moving in 40 m., and two
others in 54 m. On the second leaf some tentacles first moved in 1 hr.
11 m. After 2 hrs. many tentacles on both leaves were inflected; but
none had reached the centre within this time. In this case there could
not be the least doubt that the chloroform had exerted an anaesthetic
influence on the leaves.

On the other hand, another plant was exposed under the same vessel for
a much longer time, viz. 20 m., to twice as much chloroform. Bits of
meat were then placed on the glands of many tentacles, and all of them,
with a single exception, reached the centre in from 13 m. to 14 m. In
this case, little or no anaesthetic effect had been produced; and how
to reconcile these discordant results, I know not.

Vapour of Sulphuric Ether.--A plant was exposed for 30 m. to thirty
minims of this ether in a vessel holding 19 oz.; and bits of raw meat
were afterwards placed on many glands which had become pale-coloured;
but none of the tentacles moved. After 6 hrs. 30 m. the leaves appeared
sickly, and the discal glands were almost dry. By the next morning many
of the tentacles were dead, as were all those on which meat had been
placed; showing that matter had been absorbed from the meat which had
increased the evil effects of the vapour. After four days the plant
itself died. Another plant was exposed in the same vessel for 15 m. to
forty minims. One young, small, and tender leaf had all its tentacles
inflected, and seemed much injured. Bits of raw meat were placed on
several glands on two other and older leaves.  These glands became dry
after 6 hrs.; and seemed injured; the tentacles never moved, excepting
one which was ultimately a little inflected. The glands of the other
tentacles continued to secrete, and appeared uninjured, but the whole
plant after three days became very sickly.  [page 220]

In the two foregoing experiments the doses were evidently too large and
poisonous. With weaker doses, the anaesthetic effect was variable, as
in the case of chloroform. A plant was exposed for 5 m. to ten drops
under a 12-oz. vessel, and bits of meat were then placed on many
glands. None of the tentacles thus treated began to move in a decided
manner until 40 m. had elapsed; but then some of them moved very
quickly, so that two reached the centre after an additional interval of
only 10 m. In 2 hrs. 12 m. from the time when the meat was given, all
the tentacles reached the centre. Another plant, with two leaves, was
exposed in the same vessel for 5 m. to a rather larger dose of ether,
and bits of meat were placed on several glands. In this case one
tentacle on each leaf began to bend in 5 m.; and after 12 m. two
tentacles on one leaf, and one on the second leaf, reached the centre.
In 30 m. after the meat had been given, all the tentacles, both those
with and without meat, were closely inflected; so that the ether
apparently had stimulated these leaves, causing all the tentacles to
bend.

Vapour of Nitric Ether.--This vapour seems more injurious than that of
sulphuric ether. A plant was exposed for 5 m. in a 12-oz. vessel to
eight drops in a watch-glass, and I distinctly saw a few tentacles
curling inwards before the glass was removed. Immediately afterwards
bits of meat were placed on three glands, but no movement ensued in the
course of 18 m. The same plant was placed again under the same vessel
for 16 m. with ten drops of the ether.  None of the tentacles moved,
and next morning those with the meat were still in the same position.
After 48 hrs. one leaf seemed healthy, but the others were much
injured.

Another plant, having two good leaves, was exposed for 6 m. under a
19-oz. vessel to the vapour from ten minims of the ether, and bits of
meat were then placed on the glands of many tentacles on both leaves.
After 36 m. several of them on one leaf became inflected, and after 1
hr. almost all the tentacles, those with and without meat, nearly
reached the centre.  On the other leaf the glands began to dry in 1 hr.
40 m., and after several hours not a single tentacle was inflected; but
by the next morning, after 21 hrs., many were inflected, though they
seemed much injured. In this and the previous experiment, it is
doubtful, owing to the injury which the leaves had suffered, whether
any anaesthetic effect had been produced.

A third plant, having two good leaves, was exposed for only 4 m. in the
19-oz. vessel to the vapour from six drops. Bits of meat were then
placed on the glands of seven tentacles on the [page 221] same leaf. A
single tentacle moved after 1 hr. 23 m.; after 2 hrs. 3 m. several were
inflected; and after 3 hrs. 3 m. all the seven tentacles with meat were
well inflected. From the slowness of these movements it is clear that
this leaf had been rendered insensible for a time to the action of the
meat. A second leaf was rather differently affected; bits of meat were
placed on the glands of five tentacles, three of which were slightly
inflected in 28 m.; after 1 hr. 21 m.  one reached the centre, but the
other two were still only slightly inflected; after 3 hrs. they were
much more inflected; but even after 5 hrs. 16 m. all five had not
reached the centre.  Although some of the tentacles began to move
moderately soon, they afterwards moved with extreme slowness. By next
morning, after 20 hrs., most of the tentacles on both leaves were
closely inflected, but not quite regularly. After 48 hrs. neither leaf
appeared injured, though the tentacles were still inflected; after 72
hrs. one was almost dead, whilst the other was re-expanding and
recovering.

Carbonic Acid.--A plant was placed under a 122-oz. bell-glass filled
with this gas and standing over water; but I did not make sufficient
allowance for the absorption of the gas by the water, so that towards
the latter part of the experiment some air was drawn in. After an
exposure of 2 hrs. the plant was removed, and bits of raw meat placed
on the glands of three leaves. One of these leaves hung a little down,
and was at first partly and soon afterwards completely covered by the
water, which rose within the vessel as the gas was absorbed. On this
latter leaf the tentacles, to which meat had been given, became well
inflected in 2 m. 30 s., that is, at about the normal rate; so that
until I remembered that the leaf had been protected from the gas, and
might perhaps have absorbed oxygen from the water which was continually
drawn inwards, I falsely concluded that the carbonic acid had produced
no effect.  On the other two leaves, the tentacles with meat behaved
very differently from those on the first leaf; two of them first began
to move slightly in 1 hr. 50 m., always reckoning from the time when
the meat was placed on the glands--were plainly inflected in 2 hrs. 22
m.--and in 3 hrs 22 m. reached the centre. Three other tentacles did
not begin to move until 2 hrs. 20 m.  had elapsed, but reached the
centre at about the same time with the others, viz. in 3 hrs. 22 m.

This experiment was repeated several times with nearly the same
results, excepting that the interval before the tentacles began to move
varied a little. I will give only one other case.  [page 222] A plant
was exposed in the same vessel to the gas for 45 m., and bits of meat
were then placed on four glands. But the tentacles did not move for 1
hr. 40 m.; after 2 hrs. 30 m. all four were well inflected, and after 3
hrs. reached the centre.

The following singular phenomenon sometimes, but by no means always,
occurred. A plant was immersed for 2 hrs., and bits of meat were then
placed on several glands. In the course of 13 m. all the submarginal
tentacles on one leaf became considerably inflected; those with the
meat not in the least degree more than the others. On a second leaf,
which was rather old, the tentacles with meat, as well as a few others,
were moderately inflected. On a third leaf all the tentacles were
closely inflected, though meat had not been placed on any of the
glands.  This movement, I presume, may be attributed to excitement from
the absorption of oxygen.  The last-mentioned leaf, to which no meat
had been given, was fully re-expanded after 24 hrs.; whereas the two
other leaves had all their tentacles closely inflected over the bits of
meat which by this time had been carried to their centres. Thus these
three leaves had perfectly recovered from the effects of the gas in the
course of 24 hrs.

On another occasion some fine plants, after having been left for 2 hrs.
in the gas, were immediately given bits of meat in the usual manner,
and on their exposure to the air most of their tentacles became in 12
m. curved into a vertical or sub-vertical position, but in an extremely
irregular manner; some only on one side of the leaf and some on the
other. They remained in this position for some time; the tentacles with
the bits of meat not having at first moved more quickly or farther
inwards than the others without meat. But after 2 hrs. 20 m.  the
former began to move, and steadily went on bending until they reached
the centre. Next morning, after 22 hrs., all the tentacles on these
leaves were closely clasped over the meat which had been carried to
their centres; whilst the vertical and sub-vertical tentacles on the
other leaves to which no meat had been given had fully re-expanded.
Judging, however, from the subsequent action of a weak solution of
carbonate of ammonia on one of these latter leaves, it had not
perfectly recovered its excitability and power of movement in 22 hrs.;
but another leaf, after an additional 24 hrs., had completely
recovered, judging from the manner in which it clasped a fly placed on
its disc.

I will give only one other experiment. After the exposure of a plant
for 2 hrs. to the gas, one of its leaves was immersed in a rather
strong solution of carbonate of ammonia, together with [page 223] a
fresh leaf from another plant. The latter had most of its tentacles
strongly inflected within 30 m.; whereas the leaf which had been
exposed to the carbonic acid remained for 24 hrs. in the solution
without undergoing any inflection, with the exception of two tentacles.
This leaf had been almost completely paralysed, and was not able to
recover its sensibility whilst still in the solution, which from having
been made with distilled water probably contained little oxygen.]

Concluding Remarks on the Effects of the foregoing Agents.--As the
glands, when excited, transmit some influence to the surrounding
tentacles, causing them to bend and their glands to pour forth an
increased amount of modified secretion, I was anxious to ascertain
whether the leaves included any element having the nature of
nerve-tissue, which, though not continuous, served as the channel of
transmission. This led me to try the several alkaloids and other
substances which are known to exert a powerful influence on the nervous
system of animals; I was at first encouraged in my trials by finding
that strychnine, digitaline, and nicotine, which all act on the nervous
system, were poisonous to Drosera, and caused a certain amount of
inflection. Hydrocyanic acid, again, which is so deadly a poison to
animals, caused rapid movement of the tentacles. But as several
innocuous acids, though much diluted, such as benzoic, acetic, &c., as
well as some essential oils, are extremely poisonous to Drosera, and
quickly cause strong inflection, it seems probable that strychnine,
nicotine, digitaline, and hydrocyanic acid, excite inflection by acting
on elements in no way analogous to the nerve-cells of animals. If
elements of this latter nature had been present in the leaves, it might
have been expected that morphia, hyoscyamus, atropine, veratrine,
colchicine, curare, and diluted alcohol would have produced some marked
effect; whereas [page 224] these substances are not poisonous and have
no power, or only a very slight one, of inducing inflection. It should,
however, be observed that curare, colchicine, and veratrine are
muscle-poisons--that is, act on nerves having some special relation
with the muscles, and, therefore, could not be expected to act on
Drosera. The poison of the cobra is most deadly to animals, by
paralysing their nerve-centres,* yet is not in the least so to Drosera,
though quickly causing strong inflection.

Notwithstanding the foregoing facts, which show how widely different is
the effect of certain substances on the health or life of animals and
of Drosera, yet there exists a certain degree of parallelism in the
action of certain other substances. We have seen that this holds good
in a striking manner with the salts of sodium and potassium. Again,
various metallic salts and acids, namely those of silver, mercury,
gold, tin, arsenic, chromium, copper, and platina, most or all of which
are highly poisonous to animals, are equally so to Drosera. But it is a
singular fact that the chloride of lead and two salts of barium were
not poisonous to this plant. It is an equally strange fact, that,
though acetic and propionic acids are highly poisonous, their ally,
formic acid, is not so; and that, whilst certain vegetable acids,
namely oxalic, benzoic, &c., are poisonous in a high degree, gallic,
tannic, tartaric, and malic (all diluted to an equal degree) are not
so. Malic acid induces inflection, whilst the three other just named
vegetable acids have no such power. But a pharmacopoeia would be
requisite to describe the diversified effects of various substances on
Drosera.

* Dr. Fayrer, 'The Thanatophidia of India,' 1872, p. 4.

  Seeing that acetic, hydrocyanic, and chromic acids, acetate of
  strychnine, and vapour of ether, are poisonous to Drosera, [[page
225]] it is remarkable that Dr. Ransom (' Philosoph. Transact.' 1867,
p. 480), who used much stronger solutions of these substances than I
did, states "that the rhythmic contractility of the yolk (of the ova of
the pike) is not materially influenced by any of the poisons used,
which did not act chemically, with the exception of chloroform and
carbonic acid." I find it stated by several writers that curare has no
influence on sarcode or protoplasm, and we have seen that, though
curare excites some degree of inflection, it causes very little
aggregation of the protoplasm.) [page 225]

Of the alkaloids and their salts which were tried, several had not the
least power of inducing inflection; others, which were certainly
absorbed, as shown by the changed colour of the glands, had but a very
moderate power of this kind; others, again, such as the acetate of
quinine and digitaline, caused strong inflection.

The several substances mentioned in this chapter affect the colour of
the glands very differently. These often become dark at first, and then
very pale or white, as was conspicuously the case with glands subjected
to the poison of the cobra and citrate of strychnine. In other cases
they are from the first rendered white, as with leaves placed in hot
water and several acids; and this, I presume, is the result of the
coagulation of the albumen.  On the same leaf some glands become white
and others dark-coloured, as occurred with leaves in a solution of the
sulphate of quinine, and in the vapour of alcohol. Prolonged immersion
in nicotine, curare, and even water, blackens the glands; and this, I
believe, is due to the aggregation of the protoplasm within their
cells. Yet curare caused very little aggregation in the cells of the
tentacles, whereas nicotine and sulphate of quinine induced strongly
marked aggregation down their bases. The aggregated masses in leaves
which had been immersed for 3 hrs. 15 m. in a saturated solution of
sulphate of quinine exhibited incessant [page 226] changes of form, but
after 24 hrs. were motionless; the leaf being flaccid and apparently
dead. On the other hand, with leaves subjected for 48 hrs. to a strong
solution of the poison of the cobra, the protoplasmic masses were
unusually active, whilst with the higher animals the vibratile cilia
and white corpuscles of the blood seem to be quickly paralysed by this
substance.

With the salts of alkalies and earths, the nature of the base, and not
that of the acid, determines their physiological action on Drosera, as
is likewise the case with animals; but this rule hardly applies to the
salts of quinine and strychnine, for the acetate of quinine causes much
more inflection than the sulphate, and both are poisonous, whereas the
nitrate of quinine is not poisonous, and induces inflection at a much
slower rate than the acetate. The action of the citrate of strychnine
is also somewhat different from that of the sulphate.

Leaves which have been immersed for 24 hrs. in water, and for only 20
m. in diluted alcohol, or in a weak solution of sugar, are afterwards
acted on very slowly, or not at all, by the phosphate of ammonia,
though they are quickly acted on by the carbonate. Immersion for 20 m.
in a solution of gum arabic has no such inhibitory power. The solutions
of certain salts and acids affect the leaves, with respect to the
subsequent action of the phosphate, exactly like water, whilst others
allow the phosphate afterwards to act quickly and energetically. In
this latter case, the interstices of the cell-walls may have been
blocked up by the molecules of the salts first given in solution, so
that water could not afterwards enter, though the molecules of the
phosphate could do so, and those of the carbonate still more easily.
[page 227]

The action of camphor dissolved in water is remarkable, for it not only
soon induces inflection, but apparently renders the glands extremely
sensitive to mechanical irritation; for if they are brushed with a soft
brush, after being immersed in the solution for a short time, the
tentacles begin to bend in about 2 m. It may, however, be that the
brushing, though not a sufficient stimulus by itself, tends to excite
movement merely by reinforcing the direct action of the camphor. The
vapour of camphor, on the other hand, serves as a narcotic.

Some essential oils, both in solution and in vapour, cause rapid
inflection, others have no such power; those which I tried were all
poisonous.

Diluted alcohol (one part to seven of water) is not poisonous, does not
induce inflection, nor increase the sensitiveness of the glands to
mechanical irritation. The vapour acts as a narcotic or anaesthetic,
and long exposure to it kills the leaves.

The vapours of chloroform, sulphuric and nitric ether, act in a
singularly variable manner on different leaves, and on the several
tentacles of the same leaf. This, I suppose, is owing to differences in
the age or constitution of the leaves, and to whether certain tentacles
have lately been in action. That these vapours are absorbed by the
glands is shown by their changed colour; but as other plants not
furnished with glands are affected by these vapours, it is probable
that they are likewise absorbed by the stomata of Drosera. They
sometimes excite extraordinarily rapid inflection, but this is not an
invariable result. If allowed to act for even a moderately long time,
they kill the leaves; whilst a small dose acting for only a short time
serves as a narcotic or anaesthetic. In this case the tentacles,
whether or not they have [page 228] become inflected, are not excited
to further movement by bits of meat placed on the glands, until some
considerable time has elapsed. It is generally believed that with
animals and plants these vapours act by arresting oxidation.

Exposure to carbonic acid for 2 hrs., and in one case for only 45 m.,
likewise rendered the glands insensible for a time to the powerful
stimulus of raw meat. The leaves, however, recovered their full powers,
and did not seem in the least injured, on being left in the air for 24
or 48 hrs. We have seen in the third chapter that the process of
aggregation in leaves subjected for two hours to this gas and then
immersed in a solution of the carbonate of ammonia is much retarded, so
that a considerable time elapses before the protoplasm in the lower
cells of the tentacles becomes aggregated. In some cases, soon after
the leaves were removed from the gas and brought into the air, the
tentacles moved spontaneously; this being due, I presume, to the
excitement from the access of oxygen. These inflected tentacles,
however, could not be excited for some time afterwards to any further
movement by their glands being stimulated. With other irritable plants
it is known* that the exclusion of oxygen prevents their moving, and
arrests the movements of the protoplasm within their cells, but this
arrest is a different phenomenon from the retardation of the process of
aggregation just alluded to. Whether this latter fact ought to be
attributed to the direct action of the carbonic acid, or to the
exclusion of oxygen, I know not.

* Sachs, 'Trait de Bot.' 1874, pp. 846, 1037.  [page 229]




                           CHAPTER X.

ON THE SENSITIVENESS OF THE LEAVES, AND ON THE LINES OF TRANSMISSION
                     OF THE MOTOR IMPULSE.

Glands and summits of the tentacles alone sensitive--Transmission of
the motor impulse down the pedicels of the tentacles, and across the
blade of the leaf--Aggregation of the protoplasm, a reflex
action--First discharge of the motor impulse sudden--Direction of the
movements of the tentacles--Motor impulse transmitted through the
cellular tissue-- Mechanism of the movements--Nature of the motor
impulse--Re-expansion of the tentacles.

WE have seen in the previous chapters that many widely different
stimulants, mechanical and chemical, excite the movement of the
tentacles, as well as of the blade of the leaf; and we must now
consider, firstly, what are the points which are irritable or
sensitive, and secondly how the motor impulse is transmitted from one
point to another. The glands are almost exclusively the seat of
irritability, yet this irritability must extend for a very short
distance below them; for when they were cut off with a sharp pair of
scissors without being themselves touched, the tentacles often became
inflected. These headless tentacles frequently re-expanded; and when
afterwards drops of the two most powerful known stimulants were placed
on the cut-off ends, no effect was produced. Nevertheless these
headless tentacles are capable of subsequent inflection if excited by
an impulse sent from the disc. I succeeded on several occasions in
crushing glands between fine pincers, but this did not excite any
movement; nor did raw meat and salts of ammonia, when placed on such
crushed glands.  [page 230] It is probable that they were killed so
instantly that they were not able to transmit any motor impulse; for in
six observed cases (in two of which however the gland was quite pinched
off) the protoplasm within the cells of the tentacles did not become
aggregated; whereas in some adjoining tentacles, which were inflected
from having been roughly touched by the pincers, it was well
aggregated. In like manner the protoplasm does not become aggregated
when a leaf is instantly killed by being dipped into boiling water. On
the other hand, in several cases in which tentacles became inflected
after their glands had been cut off with sharp scissors, a distinct
though moderate degree of aggregation supervened.

The pedicels of the tentacles were roughly and repeatedly rubbed; raw
meat or other exciting substances were placed on them, both on the
upper surface near the base and elsewhere, but no distinct movement
ensued. Some bits of meat, after being left for a considerable time on
the pedicels, were pushed upwards, so as just to touch the glands, and
in a minute the tentacles began to bend. I believe that the blade of
the leaf is not sensitive to any stimulant. I drove the point of a
lancet through the blades of several leaves, and a needle three or four
times through nineteen leaves: in the former case no movement ensued;
but about a dozen of the leaves which were repeatedly pricked had a few
tentacles irregularly inflected. As, however, their backs had to be
supported during the operation, some of the outer glands, as well as
those on the disc, may have been touched; and this perhaps sufficed to
cause the slight degree of movement observed. Nitschke*says

* 'Bot. Zeitung,' 1860, p. 234.  [page 231]

that cutting and pricking the leaf does not excite movement. The
petiole of the leaf is quite insensible.

The backs of the leaves bear numerous minute papillae, which do not
secrete, but have the power of absorption. These papillae are, I
believe, rudiments of formerly existing tentacles together with their
glands. Many experiments were made to ascertain whether the backs of
the leaves could be irritated in any way, thirty-seven leaves being
thus tried. Some were rubbed for a long time with a blunt needle, and
drops of milk and other exciting fluids, raw meat, crushed flies, and
various substances, placed on others. These substances were apt soon to
become dry, showing that no secretion had been excited. Hence I
moistened them with saliva, solutions of ammonia, weak hydrochloric
acid, and frequently with the secretion from the glands of other
leaves. I also kept some leaves, on the backs of which exciting objects
had been placed, under a damp bell-glass; but with all my care I never
saw any true movement. I was led to make so many trials because,
contrary to my previous experience, Nitschke states* that, after
affixing objects to the backs of leaves by the aid of the viscid
secretion, he repeatedly saw the tentacles (and in one instance the
blade) become reflexed.  This movement, if a true one, would be most
anomalous; for it implies that the tentacles receive a motor impulse
from an unnatural source, and have the power of bending in a direction
exactly the reverse of that which is habitual to them; this power not
being of the least use to the plant, as insects cannot adhere to the
smooth backs of the leaves.

I have said that no effect was produced in the above

* 'Bot. Zeitung.' 1860, p. 437.  [page 232]

cases; but this is not strictly true, for in three instances a little
syrup was added to the bits of raw meat on the backs of leaves, in
order to keep them damp for a time; and after 36 hrs.  there was a
trace of reflexion in the tentacles of one leaf, and certainly in the
blade of another. After twelve additional hours, the glands began to
dry, and all three leaves seemed much injured. Four leaves were then
placed under a bell-glass, with their footstalks in water, with drops
of syrup on their backs, but without any meat. Two of these leaves,
after a day, had a few tentacles reflexed. The drops had now increased
considerably in size, from having imbibed moisture, so as to trickle
down the backs of the tentacles and footstalks. On the second day, one
leaf had its blade much reflexed; on the third day the tentacles of two
were much reflexed, as well as the blades of all four to a greater or
less degree. The upper side of one leaf, instead of being, as at first,
slightly concave, now presented a strong convexity upwards. Even on the
fifth day the leaves did not appear dead. Now, as sugar does not in the
least excite Drosera, we may safely attribute the reflexion of the
blades and tentacles of the above leaves to exosmose from the cells
which were in contact with the syrup, and their consequent contraction.
When drops of syrup are placed on the leaves of plants with their roots
still in damp earth, no inflection ensues, for the roots, no doubt,
pump up water as quickly as it is lost by exosmose. But if cut-off
leaves are immersed in syrup, or in any dense fluid, the tentacles are
greatly, though irregularly, inflected, some of them assuming the shape
of corkscrews; and the leaves soon become flaccid. If they are now
immersed in a fluid of low specific gravity, the tentacles re-expand.
From these [page 233] facts we may conclude that drops of syrup placed
on the backs of leaves do not act by exciting a motor impulse which is
transmitted to the tentacles; but that they cause reflexion by inducing
exosmose. Dr. Nitschke used the secretion for sticking insects to the
backs of the leaves; and I suppose that he used a large quantity, which
from being dense probably caused exosmose. Perhaps he experimented on
cut-off leaves, or on plants with their roots not supplied with enough
water.

As far, therefore, as our present knowledge serves, we may conclude
that the glands, together with the immediately underlying cells of the
tentacles, are the exclusive seats of that irritability or
sensitiveness with which the leaves are endowed. The degree to which a
gland is excited can be measured only by the number of the surrounding
tentacles which are inflected, and by the amount and rate of their
movement. Equally vigorous leaves, exposed to the same temperature (and
this is an important condition), are excited in different degrees under
the following circumstances. A minute quantity of a weak solution
produces no effect; add more, or give a rather stronger solution, and
the tentacles bend. Touch a gland once or twice, and no movement
follows; touch it three or four times, and the tentacle becomes
inflected. But the nature of the substance which is given is a very
important element: if equal-sized particles of glass (which acts only
mechanically), of gelatine, and raw meat, are placed on the discs of
several leaves, the meat causes far more rapid, energetic, and widely
extended movement than the two former substances. The number of glands
which are excited also makes a great difference in the result: place a
bit of meat on one or two of the discal [page 234] glands, and only a
few of the immediately surrounding short tentacles are inflected; place
it on several glands, and many more are acted on; place it on thirty or
forty, and all the tentacles, including the extreme marginal ones,
become closely inflected. We thus see that the impulses proceeding from
a number of glands strengthen one another, spread farther, and act on a
larger number of tentacles, than the impulse from any single gland.

Transmission of the Motor Impulse.--In every case the impulse from a
gland has to travel for at least a short distance to the basal part of
the tentacle, the upper part and the gland itself being merely carried
by the inflection of the lower part. The impulse is thus always
transmitted down nearly the whole length of the pedicel. When the
central glands are stimulated, and the extreme marginal tentacles
become inflected, the impulse is transmitted across half the diameter
of the disc; and when the glands on one side of the disc are
stimulated, the impulse is transmitted across nearly the whole width of
the disc. A gland transmits its motor impulse far more easily and
quickly down its own tentacle to the bending place than across the disc
to neighbouring tentacles. Thus a minute dose of a very weak solution
of ammonia, if given to one of the glands of the exterior tentacles,
causes it to bend and reach the centre; whereas a large drop of the
same solution, given to a score of glands on the disc, will not cause
through their combined influence the least inflection of the exterior
tentacles. Again, when a bit of meat is placed on the gland of an
exterior tentacle, I have seen movement in ten seconds, and repeatedly
within a minute; but a much larger bit placed on several glands on the
disc does not cause [page 235] the exterior tentacles to bend until
half an hour or even several hours have elapsed.

The motor impulse spreads gradually on all sides from one or more
excited glands, so that the tentacles which stand nearest are always
first affected. Hence, when the glands in the centre of the disc are
excited, the extreme marginal tentacles are the last inflected. But the
glands on different parts of the leaf transmit their motor power in a
somewhat different manner. If a bit of meat be placed on the
long-headed gland of a marginal tentacle, it quickly transmits an
impulse to its own bending portion; but never, as far as I have
observed, to the adjoining tentacles; for these are not affected until
the meat has been carried to the central glands, which then radiate
forth their conjoint impulse on all sides. On four occasions leaves
were prepared by removing some days previously all the glands from the
centre, so that these could not be excited by the bits of meat brought
to them by the inflection of the marginal tentacles; and now these
marginal tentacles re-expanded after a time without any other tentacle
being affected. Other leaves were similarly prepared, and bits of meat
were placed on the glands of two tentacles in the third row from the
outside, and on the glands of two tentacles in the fifth row. In these
four cases the impulse was sent in the first place laterally, that is,
in the same concentric row of tentacles, and then towards the centre;
but not centrifugally, or towards the exterior tentacles. In one of
these cases only a single tentacle on each side of the one with meat
was affected. In the three other cases, from half a dozen to a dozen
tentacles, both laterally and towards the centre, were well inflected
or sub-inflected.  Lastly, in [page 236] ten other experiments, minute
bits of meat were placed on a single gland or on two glands in the
centre of the disc. In order that no other glands should touch the
meat, through the inflection of the closely adjoining short tentacles,
about half a dozen glands had been previously removed round the
selected ones. On eight of these leaves from sixteen to twenty-five of
the short surrounding tentacles were inflected in the course of one or
two days; so that the motor impulse radiating from one or two of the
discal glands is able to produce this much effect. The tentacles which
had been removed are included in the above numbers; for, from standing
so close, they would certainly have been affected. On the two remaining
leaves, almost all the short tentacles on the disc were inflected. With
a more powerful stimulus than meat, namely a little phosphate of lime
moistened with saliva, I have seen the inflection spread still farther
from a single gland thus treated; but even in this case the three or
four outer rows of tentacles were not affected. From these experiments
it appears that the impulse from a single gland on the disc acts on a
greater number of tentacles than that from a gland of one of the
exterior elongated tentacles; and this probably follows, at least in
part, from the impulse having to travel a very short distance down the
pedicels of the central tentacles, so that it is able to spread to a
considerable distance all round.

Whilst examining these leaves, I was struck with the fact that in six,
perhaps seven, of them the tentacles were much more inflected at the
distal and proximal ends of the leaf (i.e.  towards the apex and base)
than on either side; and yet the tentacles on the sides stood as near
to the gland where the bit of meat lay as did those at the two ends. It
thus appeared as [page 237] if the motor impulse was transmitted from
the centre across the disc more readily in a longitudinal than in a
transverse direction; and as this appeared a new and interesting fact
in the physiology of plants, thirty-five fresh experiments were made to
test its truth. Minute bits of meat were placed on a single gland or on
a few glands, on the right or left side of the discs of eighteen
leaves; other bits of the same size being placed on the distal or
proximal ends of seventeen other leaves. Now if the motor impulse were
transmitted with equal force or at an equal rate through the blade in
all directions, a bit of meat placed at one side or at one end of the
disc ought to affect equally all the tentacles situated at an equal
distance from it; but this certainly is not the case. Before giving the
general results, it may be well to describe three or four rather
unusual cases.

[(1) A minute fragment of a fly was placed on one side of the disc, and
after 32 m. seven of the outer tentacles near the fragment were
inflected; after 10 hrs. several more became so, and after 23 hrs. a
still greater number; and now the blade of the leaf on this side was
bent inwards so as to stand up at right angles to the other side.
Neither the blade of the leaf nor a single tentacle on the opposite
side was affected; the line of separation between the two halves
extending from the footstalk to the apex. The leaf remained in this
state for three days, and on the fourth day began to re-expand; not a
single tentacle having been inflected on the opposite side.

(2) I will here give a case not included in the above thirty-five
experiments. A small fly was found adhering by its feet to the left
side of the disc. The tentacles on this side soon closed in and killed
the fly; and owing probably to its struggle whilst alive, the leaf was
so much excited that in about 24 hrs. all the tentacles on the opposite
side became inflected; but as they found no prey, for their glands did
not reach the fly, they re-expanded in the course of 15 hrs.; the
tentacles on the left side remaining clasped for several days.

(3) A bit of meat, rather larger than those commonly used, [page 238]
was placed in a medial line at the basal end of the disc, near the
footstalk; after 2 hrs. 30 m.  some neighbouring tentacles were
inflected; after 6 hrs. the tentacles on both sides of the footstalk,
and some way up both sides, were moderately inflected; after 8 hrs. the
tentacles at the further or distal end were more inflected than those
on either side; after 23 hrs. the meat was well clasped by all the
tentacles, excepting by the exterior ones on the two sides.

(4) Another bit of meat was placed at the opposite or distal end of
another leaf, with exactly the same relative results.

(5) A minute bit of meat was placed on one side of the disc; next day
the neighbouring short tentacles were inflected, as well as in a slight
degree three or four on the opposite side near the footstalk. On the
second day these latter tentacles showed signs of re-expanding, so I
added a fresh bit of meat at nearly the same spot, and after two days
some of the short tentacles on the opposite side of the disc were
inflected. As soon as these began to re-expand, I added another bit of
meat, and next day all the tentacles on the opposite side of the disc
were inflected towards the meat; whereas we have seen that those on the
same side were affected by the first bit of meat which was given.]

Now for the general results. Of the eighteen leaves on which bits of
meat were placed on the right or left sides of the disc, eight had a
vast number of tentacles inflected on the same side, and in four of
them the blade itself on this side was likewise inflected; whereas not
a single tentacle nor the blade was affected on the opposite side.
These leaves presented a very curious appearance, as if only the
inflected side was active, and the other paralysed. In the remaining
ten cases, a few tentacles became inflected beyond the medial line, on
the side opposite to that where the meat lay; but, in some of these
cases, only at the proximal or distal ends of the leaves. The
inflection on the opposite side always occurred considerably after that
on the same side, and in one instance not until the fourth day. We have
also seen [page 239] with No. 5 that bits of meat had to be added
thrice before all the short tentacles on the opposite side of the disc
were inflected.

The result was widely different when bits of meat were placed in a
medial line at the distal or proximal ends of the disc. In three of the
seventeen experiments thus made, owing either to the state of the leaf
or to the smallness of the bit of meat, only the immediately adjoining
tentacles were affected; but in the other fourteen cases the tentacles
at the opposite end of the leaf were inflected, though these were as
distant from where the meat lay as were those on one side of the disc
from the meat on the opposite side. In some of the present cases the
tentacles on the sides were not at all affected, or in a less degree,
or after a longer interval of time, than those at the opposite end. One
set of experiments is worth giving in fuller detail.  Cubes of meat,
not quite so small as those usually employed, were placed on one side
of the discs of four leaves, and cubes of the same size at the proximal
or distal end of four other leaves. Now, when these two sets of leaves
were compared after an interval of 24 hrs., they presented a striking
difference. Those having the cubes on one side were very slightly
affected on the opposite side; whereas those with the cubes at either
end had almost every tentacle at the opposite end, even the marginal
ones, closely inflected. After 48 hrs. the contrast in the state of the
two sets was still great; yet those with the meat on one side now had
their discal and submarginal tentacles on the opposite side somewhat
inflected, this being due to the large size of the cubes. Finally we
may conclude from these thirty-five experiments, not to mention the six
or seven previous ones, that the motor impulse is transmitted from any
single gland [page 240] or small group of glands through the blade to
the other tentacles more readily and effectually in a longitudinal than
in a transverse direction.

As long as the glands remain excited, and this may last for many days,
even for eleven, as when in contact with phosphate of lime, they
continue to transmit a motor impulse to the basal and bending parts of
their own pedicels, for otherwise they would re-expand. The great
difference in the length of time during which tentacles remain
inflected over inorganic objects, and over objects of the same size
containing soluble nitrogenous matter, proves the same fact. But the
intensity of the impulse transmitted from an excited gland, which has
begun to pour forth its acid secretion and is at the same time
absorbing, seems to be very small compared with that which it transmits
when first excited. Thus, when moderately large bits of meat were
placed on one side of the disc, and the discal and sub-marginal
tentacles on the opposite side became inflected, so that their glands
at last touched the meat and absorbed matter from it, they did not
transmit any motor influence to the exterior rows of tentacles on the
same side, for these never became inflected. If, however, meat had been
placed on the glands of these same tentacles before they had begun to
secrete copiously and to absorb, they undoubtedly would have affected
the exterior rows. Nevertheless, when I gave some phosphate of lime,
which is a most powerful stimulant, to several submarginal tentacles
already considerably inflected, but not yet in contact with some
phosphate previously placed on two glands in the centre of the disc,
the exterior tentacles on the same side were acted on.

When a gland is first excited, the motor impulse is discharged within a
few seconds, as we know from the [page 241] bending of the tentacle;
and it appears to be discharged at first with much greater force than
afterwards. Thus, in the case above given of a small fly naturally
caught by a few glands on one side of a leaf, an impulse was slowly
transmitted from them across the whole breadth of the leaf, causing the
opposite tentacles to be temporarily inflected, but the glands which
remained in contact with the insect, though they continued for several
days to send an impulse down their own pedicels to the bending place,
did not prevent the tentacles on the opposite side from quickly
re-expanding; so that the motor discharge must at first have been more
powerful than afterwards.

When an object of any kind is placed on the disc, and the surrounding
tentacles are inflected, their glands secrete more copiously and the
secretion becomes acid, so that some influence is sent to them from the
discal glands. This change in the nature and amount of the secretion
cannot depend on the bending of the tentacles, as the glands of the
short central tentacles secrete acid when an object is placed on them,
though they do not themselves bend.  Therefore I inferred that the
glands of the disc sent some influence up the surrounding tentacles to
their glands, and that these reflected back a motor impulse to their
basal parts; but this view was soon proved erroneous. It was found by
many trials that tentacles with their glands closely cut off by sharp
scissors often become inflected and again re-expand, still appearing
healthy. One which was observed continued healthy for ten days after
the operation. I therefore cut the glands off twenty-five tentacles, at
different times and on different leaves, and seventeen of these soon
became inflected, and afterwards re-expanded.  The re-expansion
commenced in about [page 242] 8 hrs. or 9 hrs., and was completed in
from 22 hrs. to 30 hrs. from the time of inflection.  After an interval
of a day or two, raw meat with saliva was placed on the discs of these
seventeen leaves, and when observed next day, seven of the headless
tentacles were inflected over the meat as closely as the uninjured ones
on the same leaves; and an eighth headless tentacle became inflected
after three additional days. The meat was removed from one of these
leaves, and the surface washed with a little stream of water, and after
three days the headless tentacle re-expanded for the second time. These
tentacles without glands were, however, in a different state from those
provided with glands and which had absorbed matter from the meat, for
the protoplasm within the cells of the former had undergone far less
aggregation. From these experiments with headless tentacles it is
certain that the glands do not, as far as the motor impulse is
concerned, act in a reflex manner like the nerve-ganglia of animals.

But there is another action, namely that of aggregation, which in
certain cases may be called reflex, and it is the only known instance
in the vegetable kingdom. We should bear in mind that the process does
not depend on the previous bending of the tentacles, as we clearly see
when leaves are immersed in certain strong solutions. Nor does it
depend on increased secretion from the glands, and this is shown by
several facts, more especially by the papillae, which do not secrete,
yet undergoing aggregation, if given carbonate of ammonia or an
infusion of raw meat. When a gland is directly stimulated in any way,
as by the pressure of a minute particle of glass, the protoplasm within
the cells of the gland first becomes aggregated, then that in the cells
immediately beneath the gland, and so lower and lower down the
tentacles to their bases;-- [page 243] that is, if the stimulus has
been sufficient and not injurious. Now, when the glands of the disc are
excited, the exterior tentacles are affected in exactly the same
manner: the aggregation always commences in their glands, though these
have not been directly excited, but have only received some influence
from the disc, as shown by their increased acid secretion. The
protoplasm within the cells immediately beneath the glands are next
affected, and so downwards from cell to cell to the bases of the
tentacles. This process apparently deserves to be called a reflex
action, in the same manner as when a sensory nerve is irritated, and
carries an impression to a ganglion which sends back some influence to
a muscle or gland, causing movement or increased secretion; but the
action in the two cases is probably of a widely different nature. After
the protoplasm in a tentacle has been aggregated, its redissolution
always begins in the lower part, and slowly travels up the pedicel to
the gland, so that the protoplasm last aggregated is first redissolved.
This probably depends merely on the protoplasm being less and less
aggregated, lower and lower down in the tentacles, as can be seen
plainly when the excitement has been slight. As soon, therefore, as the
aggregating action altogether ceases, redissolution naturally commences
in the less strongly aggregated matter in the lowest part of the
tentacle, and is there first completed.

Direction of the Inflected Tentacles.--When a particle of any kind is
placed on the gland of one of the outer tentacles, this invariably
moves towards the centre of the leaf; and so it is with all the
tentacles of a leaf immersed in any exciting fluid. The glands of the
exterior tentacles then form a ring round the middle part of the disc,
as shown in a previous figure (fig. 4, [page 244] p. 10). The short
tentacles within this ring still retain their vertical position, as
they likewise do when a large object is placed on their glands, or when
an insect is caught by them. In this latter case we can see that the
inflection of the short central tentacles would be useless, as their
glands are already in contact with their prey.

FIG. 10.  (Drosera rotundifolia.) Leaf (enlarged) with the tentacles
inflected over a bit of meat placed on one side of the disc.

The result is very different when a single gland on one side of the
disc is excited, or a few in a group. These send an impulse to the
surrounding tentacles, which do not now bend towards the centre of the
leaf, but to the point of excitement. We owe this capital observation
to Nitschke,* and since reading his paper a few years ago, I have
repeatedly verified it. If a minute bit of meat be placed by the aid of
a needle on a single gland, or on three or four together, halfway
between the centre and the circumference of the disc, the directed
movement of the surrounding tentacles is well exhibited. An accurate
drawing of a leaf with meat in this position is here reproduced (fig.
10), and we see the tentacles, including some of the exterior ones,
accurately directed to the point where the meat lay. But a much better

* 'Bot. Zeitung,' 1860, p. 240.  [page 245]

plan is to place a particle of the phosphate of lime moistened with
saliva on a single gland on one side of the disc of a large leaf, and
another particle on a single gland on the opposite side. In four such
trials the excitement was not sufficient to affect the outer tentacles,
but all those near the two points were directed to them, so that two
wheels were formed on the disc of the same leaf; the pedicels of the
tentacles forming the spokes, and the glands united in a mass over the
phosphate representing the axles. The precision with which each
tentacle pointed to the particle was wonderful; so that in some cases I
could detect no deviation from perfect accuracy. Thus, although the
short tentacles in the middle of the disc do not bend when their glands
are excited in a direct manner, yet if they receive a motor impulse
from a point on one side, they direct themselves to the point equally
well with the tentacles on the borders of the disc.

In these experiments, some of the short tentacles on the disc, which
would have been directed to the centre, had the leaf been immersed in
an exciting fluid, were now inflected in an exactly opposite direction,
viz. towards the circumference. These tentacles, therefore, had
deviated as much as 180o from the direction which they would have
assumed if their own glands had been stimulated, and which may be
considered as the normal one. Between this, the greatest possible and
no deviation from the normal direction, every degree could be observed
in the tentacles on these several leaves. Notwithstanding the precision
with which the tentacles generally were directed, those near the
circumference of one leaf were not accurately directed towards some
phosphate of lime at a rather distant point on the opposite side of the
disc. It appeared as if the motor [page 246] impulse in passing
transversely across nearly the whole width of the disc had departed
somewhat from a true course. This accords with what we have already
seen of the impulse travelling less readily in a transverse than in a
longitudinal direction. In some other cases, the exterior tentacles did
not seem capable of such accurate movement as the shorter and more
central ones.

Nothing could be more striking than the appearance of the above four
leaves, each with their tentacles pointing truly to the two little
masses of the phosphate on their discs. We might imagine that we were
looking at a lowly organised animal seizing prey with its arms. In the
case of Drosera the explanation of this accurate power of movement, no
doubt, lies in the motor impulse radiating in all directions, and
whichever side of a tentacle it first strikes, that side contracts, and
the tentacle consequently bends towards the point of excitement. The
pedicels of the tentacles are flattened, or elliptic in section. Near
the bases of the short central tentacles, the flattened or broad face
is formed of about five longitudinal rows of cells; in the outer
tentacles of the disc it consists of about six or seven rows; and in
the extreme marginal tentacles of above a dozen rows. As the flattened
bases are thus formed of only a few rows of cells, the precision of the
movements of the tentacles is the more remarkable; for when the motor
impulse strikes the base of a tentacle in a very oblique direction
relatively to its broad face, scarcely more than one or two cells
towards one end can be affected at first, and the contraction of these
cells must draw the whole tentacle into the proper direction. It is,
perhaps, owing to the exterior pedicels being much flattened that they
do not bend quite so accurately to the point of excitement as the [page
247] more central ones. The properly directed movement of the tentacles
is not an unique case in the vegetable kingdom, for the tendrils of
many plants curve towards the side which is touched; but the case of
Drosera is far more interesting, as here the tentacles are not directly
excited, but receive an impulse from a distant point; nevertheless,
they bend accurately towards this point.

FIG. 11.  (Drosera rotundifolia.) Diagram showing the distribution of
the vascular tissue in a small leaf.

On the Nature of the Tissues through which the Motor Impulse is
Transmitted.--It will be necessary first to describe briefly the course
of the main fibro-vascular bundles. These are shown in the accompanying
sketch (fig. 11) of a small leaf. Little vessels from the neighbouring
bundles enter all the many tentacles with which the surface is studded;
but these are not here represented. The central trunk, which runs up
the footstalk, bifurcates near the centre of the leaf, each branch
bifurcating again and again according to the size of the leaf. This
central trunk sends off, low down on each side, a delicate branch,
which may be called the sublateral branch. There is also, on each side,
a main lateral branch or bundle, which bifurcates in the same manner as
the others. Bifurcation does not imply that any single vessel divides,
but that a bundle [page 248] divides into two. By looking to either
side of the leaf, it will be seen that a branch from the great central
bifurcation inosculates with a branch from the lateral bundle, and that
there is a smaller inosculation between the two chief branches of the
lateral bundle. The course of the vessels is very complex at the larger
inosculation; and here vessels, retaining the same diameter, are often
formed by the union of the bluntly pointed ends of two vessels, but
whether these points open into each other by their attached surfaces, I
do not know. By means of the two inosculations all the vessels on the
same side of the leaf are brought into some sort of connection. Near
the circumference of the larger leaves the bifurcating branches also
come into close union, and then separate again, forming a continuous
zigzag line of vessels round the whole circumference. But the union of
the vessels in this zigzag line seems to be much less intimate than at
the main inosculation. It should be added that the course of the
vessels differs somewhat in different leaves, and even on opposite
sides of the same leaf, but the main inosculation is always present.

Now in my first experiments with bits of meat placed on one side of the
disc, it so happened that not a single tentacle was inflected on the
opposite side; and when I saw that the vessels on the same side were
all connected together by the two inosculations, whilst not a vessel
passed over to the opposite side, it seemed probable that the motor
impulse was conducted exclusively along them.

In order to test this view, I divided transversely with the point of a
lancet the central trunks of four leaves, just beneath the main
bifurcation; and two days afterwards placed rather large bits of raw
meat [page 249] (a most powerful stimulant) near the centre of the disc
above the incision--that is, a little towards the apex--with the
following results:--

[(1) This leaf proved rather torpid: after 4 hrs. 40 m. (in all cases
reckoning from the time when the meat was given) the tentacles at the
distal end were a little inflected, but nowhere else; they remained so
for three days, and re-expanded on the fourth day. The leaf was then
dissected, and the trunk, as well as the two sublateral branches, were
found divided.

(2) After 4 hrs. 30 m. many of the tentacles at the distal end were
well inflected. Next day the blade and all the tentacles at this end
were strongly inflected, and were separated by a distinct transverse
line from the basal half of the leaf, which was not in the least
affected. On the third day, however, some of the short tentacles on the
disc near the base were very slightly inflected. The incision was found
on dissection to extend across the leaf as in the last case.

(3) After 4 hrs. 30 m. strong inflection of the tentacles at the distal
end, which during the next two days never extended in the least to the
basal end. The incision as before.

(4) This leaf was not observed until 15 hrs. had elapsed, and then all
the tentacles, except the extreme marginal ones, were found equally
well inflected all round the leaf. On careful examination the spiral
vessels of the central trunk were certainly divided; but the incision
on one side had not passed through the fibrous tissue surrounding these
vessels, though it had passed through the tissue on the other side.*]

The appearance presented by the leaves (2) and (3) was very curious,
and might be aptly compared with that of a man with his backbone broken
and lower extremities paralysed.  Excepting that the line between the
two halves was here transverse instead of longitudinal, these leaves
were in the same state as some of those in the former experiments, with
bits of meat placed on one side of the disc. The case of leaf (4)

* M. Ziegler made similar experiments by cutting the spiral vessels of
Drosera intermedia('Comptes rendus,' 1874, p. 1417), but arrived at
conclusions widely different from mine.  [page 250]

proves that the spiral vessels of the central trunk may be divided, and
yet the motor impulse be transmitted from the distal to the basal end;
and this led me at first to suppose that the motor force was sent
through the closely surrounding fibrous tissue; and that if one half of
this tissue was left undivided, it sufficed for complete transmission.
But opposed to this conclusion is the fact that no vessels pass
directly from one side of the leaf to the other, and yet, as we have
seen, if a rather large bit of meat is placed on one side, the motor
impulse is sent, though slowly and imperfectly, in a transverse
direction across the whole breadth of the leaf. Nor can this latter
fact be accounted for by supposing that the transmission is effected
through the two inosculations, or through the circumferential zigzag
line of union, for had this been the case, the exterior tentacles on
the opposite side of the disc would have been affected before the more
central ones, which never occurred. We have also seen that the extreme
marginal tentacles appear to have no power to transmit an impulse to
the adjoining tentacles; yet the little bundle of vessels which enters
each marginal tentacle sends off a minute branch to those on both
sides, and this I have not observed in any other tentacles; so that the
marginal ones are more closely connected together by spiral vessels
than are the others, and yet have much less power of communicating a
motor impulse to one another.

But besides these several facts and arguments we have conclusive
evidence that the motor impulse is not sent, at least exclusively,
through the spiral vessels, or through the tissue immediately
surrounding them. We know that if a bit of meat is placed on a gland
(the immediately adjoining ones having been removed) on any part of the
disc, all the short sur- [page 251] rounding tentacles bend almost
simultaneously with great precision towards it. Now there are tentacles
on the disc, for instance near the extremities of the sublateral
bundles (fig. 11), which are supplied with vessels that do not come
into contact with the branches that enter the surrounding tentacles,
except by a very long and extremely circuitous course. Nevertheless, if
a bit of meat is placed on the gland of a tentacle of this kind, all
the surrounding ones are inflected towards it with great precision. It
is, of course, possible that an impulse might be sent through a long
and circuitous course, but it is obviously impossible that the
direction of the movement could be thus communicated, so that all the
surrounding tentacles should bend precisely to the point of excitement.
The impulse no doubt is transmitted in straight radiating lines from
the excited gland to the surrounding tentacles; it cannot, therefore,
be sent along the fibro-vascular bundles. The effect of cutting the
central vessels, in the above cases, in preventing the transmission of
the motor impulse from the distal to the basal end of a leaf, may be
attributed to a considerable space of the cellular tissue having been
divided. We shall hereafter see, when we treat of Dionaea, that this
same conclusion, namely that the motor impulse is not transmitted by
the fibro-vascular bundles, is plainly confirmed; and Prof. Cohn has
come to the same conclusion with respect to Aldrovanda--both members of
the Droseraceae.

As the motor impulse is not transmitted along the vessels, there
remains for its passage only the cellular tissue; and the structure of
this tissue explains to a certain extent how it travels so quickly down
the long exterior tentacles, and much more slowly across the blade of
the leaf.  We shall also see why it crosses [page 252] the blade more
quickly in a longitudinal than in a transverse direction; though with
time it can pass in any direction. We know that the same stimulus
causes movement of the tentacles and aggregation of the protoplasm, and
that both influences originate in and proceed from the glands within
the same brief space of time. It seems therefore probable that the
motor impulse consists of the first commencement of a molecular change
in the protoplasm, which, when well developed, is plainly visible, and
has been designated aggregation; but to this subject I shall return. We
further know that in the transmission of the aggregating process the
chief delay is caused by the passage of the transverse cell-walls; for
as the aggregation travels down the tentacles, the contents of each
successive cell seem almost to flash into a cloudy mass. We may
therefore infer that the motor impulse is in like manner delayed
chiefly by passing through the cell-walls.

The greater celerity with which the impulse is transmitted down the
long exterior tentacles than across the disc may be largely attributed
to its being closely confined within the narrow pedicel, instead of
radiating forth on all sides as on the disc. But besides this
confinement, the exterior cells of the tentacles are fully twice as
long as those of the disc; so that only half the number of transverse
partitions have to be traversed in a given length of a tentacle,
compared with an equal space on the disc; and there would be in the
same proportion less retardation of the impulse. Moreover, in sections
of the exterior tentacles given by Dr.  Warming,* the parenchymatous

* 'Videnskabelige Meddelelser de la Soc. d'Hist. nat. de Copenhague,'
Nos. 10-12, 1872, woodcuts iv. and v.  [page 253]

cells are shown to be still more elongated; and these would form the
most direct line of communication from the gland to the bending place
of the tentacle. If the impulse travels down the exterior cells, it
would have to cross from between twenty to thirty transverse
partitions; but rather fewer if down the inner parenchymatous tissue.
In either case it is remarkable that the impulse is able to pass
through so many partitions down nearly the whole length of the pedicel,
and to act on the bending place, in ten seconds. Why the impulse, after
having passed so quickly down one of the extreme marginal tentacles
(about 1/20 of an inch in length), should never, as far as I have seen,
affect the adjoining tentacles, I do not understand. It may be in part
accounted for by much energy being expended in the rapidity of the
transmission.

Most of the cells of the disc, both the superficial ones and the larger
cells which form the five or six underlying layers, are about four
times as long as broad. They are arranged almost longitudinally,
radiating from the footstalk. The motor impulse, therefore, when
transmitted across the disc, has to cross nearly four times as many
cell-walls as when transmitted in a longitudinal direction, and would
consequently be much delayed in the former case. The cells of the disc
converge towards the bases of the tentacles, and are thus fitted to
convey the motor impulse to them from all sides. On the whole, the
arrangement and shape of the cells, both those of the disc and
tentacles, throw much light on the rate and manner of diffusion of the
motor impulse. But why the impulse proceeding from the glands of the
exterior rows of tentacles tends to travel laterally and towards the
centre of the leaf, but not centrifugally, is by no means clear.  [page
254]

Mechanism of the Movements, and Nature of the Motor Impulse.--Whatever
may be the means of movement, the exterior tentacles, considering their
delicacy, are inflected with much force. A bristle, held so that a
length of 1 inch projected from a handle, yielded when I tried to lift
with it an inflected tentacle, which was somewhat thinner than the
bristle. The amount or extent, also, of the movement is great. Fully
expanded tentacles in becoming inflected sweep through an angle of
180o; and if they are beforehand reflexed, as often occurs, the angle
is considerably greater. It is probably the superficial cells at the
bending place which chiefly or exclusively contract; for the interior
cells have very delicate walls, and are so few in number that they
could hardly cause a tentacle to bend with precision to a definite
point. Though I carefully looked, I could never detect any wrinkling of
the surface at the bending place, even in the case of a tentacle
abnormally curved into a complete circle, under circumstances hereafter
to be mentioned.

All the cells are not acted on, though the motor impulse passes through
them. When the gland of one of the long exterior tentacles is excited,
the upper cells are not in the least affected; about halfway down there
is a slight bending, but the chief movement is confined to a short
space near the base; and no part of the inner tentacles bends except
the basal portion.  With respect to the blade of the leaf, the motor
impulse may be transmitted through many cells, from the centre to the
circumference, without their being in the least affected, or they may
be strongly acted on and the blade greatly inflected. In the latter
case the movement seems to depend partly on the strength of the
stimulus, and partly on [page 255] its nature, as when leaves are
immersed in certain fluids.

The power of movement which various plants possess, when irritated, has
been attributed by high authorities to the rapid passage of fluid out
of certain cells, which, from their previous state of tension,
immediately contract.* Whether or not this is the primary cause of such
movements, fluid must pass out of closed cells when they contract or
are pressed together in one direction, unless they at the same time
expand in some other direction. For instance, fluid can be seen to ooze
from the surface of any young and vigorous shoot if slowly bent into a
semi-circle.  In the case of Drosera there is certainly much movement
of the fluid throughout the tentacles whilst they are undergoing
inflection. Many leaves can be found in which the purple fluid within
the cells is of an equally dark tint on the upper and lower sides of
the tentacles, extending also downwards on both sides to equally near
their bases. If the tentacles of such a leaf are excited into movement,
it will generally be found after some hours that the cells on the
concave side are much paler than they were before, or are quite
colourless, those on the convex side having become much darker. In two
instances, after particles of hair had been placed on glands, and when
in the course of 1 hr. 10 m. the tentacles were incurved halfway
towards the centre of the leaf, this change of colour in the two sides
was conspicuously plain. In another case, after a bit of meat had been
placed on a gland, the purple colour was observed at intervals to be
slowly travelling from the upper to the lower part, down the convex
side of

* Sachs, 'Trait de Bot.' 3rd edit. 1874, p. 1038. This view was, I
believe, first suggested by Lamarck.

  Sachs, ibid. p. 919.  [page 256]

the bending tentacle. But it does not follow from these observations
that the cells on the convex side become filled with more fluid during
the act of inflection than they contained before; for fluid may all the
time be passing into the disc or into the glands which then secrete
freely.

The bending of the tentacles, when leaves are immersed in a dense
fluid, and their subsequent re-expansion in a less dense fluid, show
that the passage of fluid from or into the cells can cause movements
like the natural ones. But the inflection thus caused is often
irregular; the exterior tentacles being sometimes spirally curved.
Other unnatural movements are likewise caused by the application of
dense fluids, as in the case of drops of syrup placed on the backs of
leaves and tentacles. Such movements may be compared with the
contortions which many vegetable tissues undergo when subjected to
exosmose. It is therefore doubtful whether they throw any light on the
natural movements.

If we admit that the outward passage of fluid is the cause of the
bending of the tentacles, we must suppose that the cells, before the
act of inflection, are in a high state of tension, and that they are
elastic to an extraordinary degree; for otherwise their contraction
could not cause the tentacles often to sweep through an angle of above
180o. Prof. Cohn, in his interesting paper* on the movements of the
stamens of certain Compositae, states that these organs, when dead, are
as elastic as threads of india-rubber, and are then only half as long
as they were when alive. He believes that the living protoplasm

* 'Abhand. der Schles. Gesell. fr vaterl. Cultur,' 1861, Heft i. An
excellent abstract of this paper is given in the 'Annals and Mag. of
Nat. Hist.' 3rd series, 1863, vol. xi. pp. 188-197.  [page 257]

within their cells is ordinarily in a state of expansion, but is
paralysed by irritation, or may be said to suffer temporary death; the
elasticity of the cell-walls then coming into play, and causing the
contraction of the stamens. Now the cells on the upper or concave side
of the bending part of the tentacles of Drosera do not appear to be in
a state of tension, nor to be highly elastic; for when a leaf is
suddenly killed, or dies slowly, it is not the upper but the lower
sides of the tentacles which contract from elasticity. We may,
therefore, conclude that their movements cannot be accounted for by the
inherent elasticity of certain cells, opposed as long as they are alive
and not irritated by the expanded state of their contents.

A somewhat different view has been advanced by other
physiologists--namely that the protoplasm, when irritated, contracts
like the soft sarcode of the muscles of animals. In Drosera the fluid
within the cells of the tentacles at the bending place appears under
the microscope thin and homogeneous, and after aggregation consists of
small, soft masses of matter, undergoing incessant changes of form and
floating in almost colourless fluid. These masses are completely
redissolved when the tentacles re-expand. Now it seems scarcely
possible that such matter should have any direct mechanical power; but
if through some molecular change it were to occupy less space than it
did before, no doubt the cell-walls would close up and contract. But in
this case it might be expected that the walls would exhibit wrinkles,
and none could ever be seen. Moreover, the contents of all the cells
seem to be of exactly the same nature, both before and after
aggregation; and yet only a few of the basal cells contract, the rest
of the tentacle remaining straight.

A third view maintained by some physiologists, [page 258] though
rejected by most others, is that the whole cell, including the walls,
actively contracts.  If the walls are composed solely of
non-nitrogenous cellulose, this view is highly improbable; but it can
hardly be doubted that they must be permeated by proteid matter, at
least whilst they are growing. Nor does there seem any inherent
improbability in the cell-walls of Drosera contracting, considering
their high state of organisation; as shown in the case of the glands by
their power of absorption and secretion, and by being exquisitely
sensitive so as to be affected by the pressure of the most minute
particles. The cell-walls of the pedicels also allow various impulses
to pass through them, inducing movement, increased secretion and
aggregation. On the whole the belief that the walls of certain cells
contract, some of their contained fluid being at the same time forced
outwards, perhaps accords best with the observed facts. If this view is
rejected, the next most probable one is that the fluid contents of the
cells shrink, owing to a change in their molecular state, with the
consequent closing in of the walls. Anyhow, the movement can hardly be
attributed to the elasticity of the walls, together with a previous
state of tension.

With respect to the nature of the motor impulse which is transmitted
from the glands down the pedicels and across the disc, it seems not
improbable that it is closely allied to that influence which causes the
protoplasm within the cells of the glands and tentacles to aggregate.
We have seen that both forces originate in and proceed from the glands
within a few seconds of the same time, and are excited by the same
causes. The aggregation of the protoplasm lasts almost as long as the
tentacles remain inflected, even though this be for more than a week;
but the [page 259] protoplasm is redissolved at the bending place
shortly before the tentacles re-expand, showing that the exciting cause
of the aggregating process has then quite ceased. Exposure to carbonic
acid causes both the latter process and the motor impulse to travel
very slowly down the tentacles. We know that the aggregating process is
delayed in passing through the cell- walls, and we have good reason to
believe that this holds good with the motor impulse; for we can thus
understand the different rates of its transmission in a longitudinal
and transverse line across the disc. Under a high power the first sign
of aggregation is the appearance of a cloud, and soon afterwards of
extremely fine granules, in the homogeneous purple fluid within the
cells; and this apparently is due to the union of molecules of
protoplasm. Now it does not seem an improbable view that the same
tendency--namely for the molecules to approach each other--should be
communicated to the inner surfaces of the cell-walls which are in
contact with the protoplasm; and if so, their molecules would approach
each other, and the cell-wall would contract.

To this view it may with truth be objected that when leaves are
immersed in various strong solutions, or are subjected to a heat of
above 130o Fahr. (54o.4 Cent.), aggregation ensues, but there is no
movement. Again, various acids and some other fluids cause rapid
movement, but no aggregation, or only of an abnormal nature, or only
after a long interval of time; but as most of these fluids are more or
less injurious, they may check or prevent the aggregating process by
injuring or killing the protoplasm. There is another and more important
difference in the two processes: when the glands on the disc are
excited, they transmit some influence up the surrounding [page 260]
tentacles, which acts on the cells at the bending place, but does not
induce aggregation until it has reached the glands; these then send
back some other influence, causing the protoplasm to aggregate, first
in the upper and then in the lower cells.

The Re-expansion of the Tentacles.--This movement is always slow and
gradual. When the centre of the leaf is excited, or a leaf is immersed
in a proper solution, all the tentacles bend directly towards the
centre, and afterwards directly back from it. But when the point of
excitement is on one side of the disc, the surrounding tentacles bend
towards it, and therefore obliquely with respect to their normal
direction; when they afterwards re-expand, they bend obliquely back, so
as to recover their original positions. The tentacles farthest from an
excited point, wherever that may be, are the last and the least
affected, and probably in consequence of this they are the first to
re-expand. The bent portion of a closely inflected tentacle is in a
state of active contraction, as shown by the following experiment. Meat
was placed on a leaf, and after the tentacles were closely inflected
and had quite ceased to move, narrow strips of the disc, with a few of
the outer tentacles attached to it, were cut off and laid on one side
under the microscope. After several failures, I succeeded in cutting
off the convex surface of the bent portion of a tentacle. Movement
immediately recommenced, and the already greatly bent portion went on
bending until it formed a perfect circle; the straight distal portion
of the tentacle passing on one side of the strip. The convex surface
must therefore have previously been in a state of tension, sufficient
to counter-balance that of the concave surface, which, when free,
curled into a complete ring.

The tentacles of an expanded and unexcited leaf [page 261] are
moderately rigid and elastic; if bent by a needle, the upper end yields
more easily than the basal and thicker part, which alone is capable of
becoming inflected. The rigidity of this basal part seems due to the
tension of the outer surface balancing a state of active and persistent
contraction of the cells of the inner surface. I believe that this is
the case, because, when a leaf is dipped into boiling water, the
tentacles suddenly become reflexed, and this apparently indicates that
the tension of the outer surface is mechanical, whilst that of the
inner surface is vital, and is instantly destroyed by the boiling
water. We can thus also understand why the tentacles as they grow old
and feeble slowly become much reflexed. If a leaf with its tentacles
closely inflected is dipped into boiling water, these rise up a little,
but by no means fully re-expand. This may be owing to the heat quickly
destroying the tension and elasticity of the cells of the convex
surface; but I can hardly believe that their tension, at any one time,
would suffice to carry back the tentacles to their original position,
often through an angle of above 180o. It is more probable that fluid,
which we know travels along the tentacles during the act of inflection,
is slowly re-attracted into the cells of the convex surface, their
tension being thus gradually and continually increased.

A recapitulation of the chief facts and discussions in this chapter
will be given at the close of the next chapter.  [page 262]




                          CHAPTER XI.

RECAPITULATION OF THE CHIEF OBSERVATIONS ON DROSERA ROTUNDIFOLIA.

As summaries have been given to most of the chapters, it will be
sufficient here to recapitulate, as briefly as I can, the chief points.
In the first chapter a preliminary sketch was given of the structure of
the leaves, and of the manner in which they capture insects. This is
effected by drops of extremely viscid fluid surrounding the glands and
by the inward movement of the tentacles. As the plants gain most of
their nutriment by this means, their roots are very poorly developed;
and they often grow in places where hardly any other plant except
mosses can exist. The glands have the power of absorption, besides that
of secretion.  They are extremely sensitive to various stimulants,
namely repeated touches, the pressure of minute particles, the
absorption of animal matter and of various fluids, heat, and galvanic
action. A tentacle with a bit of raw meat on the gland has been seen to
begin bending in 10 s., to be strongly incurved in 5 m., and to reach
the centre of the leaf in half an hour. The blade of the leaf often
becomes so much inflected that it forms a cup, enclosing any object
placed on it.

A gland, when excited, not only sends some influence down its own
tentacle, causing it to bend, but likewise to the surrounding
tentacles, which become incurved; so that the bending place can be
acted on by an impulse received from opposite directions, [page 263]
namely from the gland on the summit of the same tentacle, and from one
or more glands of the neighbouring tentacles. Tentacles, when
inflected, re-expand after a time, and during this process the glands
secrete less copiously, or become dry. As soon as they begin to secrete
again, the tentacles are ready to re-act; and this may be repeated at
least three, probably many more times.

It was shown in the second chapter that animal substances placed on the
discs cause much more prompt and energetic inflection than do inorganic
bodies of the same size, or mere mechanical irritation; but there is a
still more marked difference in the greater length of time during which
the tentacles remain inflected over bodies yielding soluble and
nutritious matter, than over those which do not yield such matter.
Extremely minute particles of glass, cinders, hair, thread,
precipitated chalk, &c., when placed on the glands of the outer
tentacles, cause them to bend. A particle, unless it sinks through the
secretion and actually touches the surface of the gland with some one
point, does not produce any effect. A little bit of thin human hair
8/1000 of an inch (.203 mm.) in length, and weighing only 1/78740 of a
grain (.000822 mg.), though largely supported by the dense secretion,
suffices to induce movement. It is not probable that the pressure in
this case could have amounted to that from the millionth of a grain.
Even smaller particles cause a slight movement, as could be seen
through a lens. Larger particles than those of which the measurements
have been given cause no sensation when placed on the tongue, one of
the most sensitive parts of the human body.

Movement ensues if a gland is momentarily touched three or four times;
but if touched only once or twice, [page 264] though with considerable
force and with a hard object, the tentacle does not bend. The plant is
thus saved from much useless movement, as during a high wind the glands
can hardly escape being occasionally brushed by the leaves of
surrounding plants. Though insensible to a single touch, they are
exquisitely sensitive, as just stated, to the slightest pressure if
prolonged for a few seconds; and this capacity is manifestly of service
to the plant in capturing small insects. Even gnats, if they rest on
the glands with their delicate feet, are quickly and securely embraced.
The glands are insensible to the weight and repeated blows of drops of
heavy rain, and the plants are thus likewise saved from much useless
movement.

The description of the movements of the tentacles was interrupted in
the third chapter for the sake of describing the process of
aggregation. This process always commences in the cells of the glands,
the contents of which first become cloudy; and this has been observed
within 10 s. after a gland has been excited. Granules just resolvable
under a very high power soon appear, sometimes within a minute, in the
cells beneath the glands; and these then aggregate into minute spheres.
The process afterwards travels down the tentacles, being arrested for a
short time at each transverse partition. The small spheres coalesce
into larger spheres, or into oval, club-headed, thread- or
necklace-like, or otherwise shaped masses of protoplasm, which,
suspended in almost colourless fluid, exhibit incessant spontaneous
changes of form.  These frequently coalesce and again separate. If a
gland has been powerfully excited, all the cells down to the base of
the tentacle are affected. In cells, especially if filled with dark red
fluid, the first step in the [page 265] process often is the formation
of a dark red, bag-like mass of protoplasm, which afterwards divides
and undergoes the usual repeated changes of form. Before any
aggregation has been excited, a sheet of colourless protoplasm,
including granules (the primordial utricle of Mohl), flows round the
walls of the cells; and this becomes more distinct after the contents
have been partially aggregated into spheres or bag-like masses. But
after a time the granules are drawn towards the central masses and
unite with them; and then the circulating sheet can no longer be
distinguished, but there is still a current of transparent fluid within
the cells.

Aggregation is excited by almost all the stimulants which induce
movement; such as the glands being touched two or three times, the
pressure of minute inorganic particles, the absorption of various
fluids, even long immersion in distilled water, exosmose, and heat. Of
the many stimulants tried, carbonate of ammonia is the most energetic
and acts the quickest:  a dose of 1/134400 of a grain (.00048 mg.)
given to a single gland suffices to cause in one hour well-marked
aggregation in the upper cells of the tentacle. The process goes on
only as long as the protoplasm is in a living, vigorous, and oxygenated
condition.

The result is in all respects exactly the same, whether a gland has
been excited directly, or has received an influence from other and
distant glands. But there is one important difference: when the central
glands are irritated, they transmit centrifugally an influence up the
pedicels of the exterior tentacles to their glands; but the actual
process of aggregation travels centripetally, from the glands of the
exterior tentacles down their pedicels. The exciting influence,
therefore, which is transmitted from [page 266] one part of the leaf to
another must be different from that which actually induces aggregation.
The process does not depend on the glands secreting more copiously than
they did before; and is independent of the inflection of the tentacles.
It continues as long as the tentacles remain inflected, and as soon as
these are fully re-expanded, the little masses of protoplasm are all
redissolved; the cells becoming filled with homogeneous purple fluid,
as they were before the leaf was excited.

As the process of aggregation can be excited by a few touches, or by
the pressure of insoluble particles, it is evidently independent of the
absorption of any matter, and must be of a molecular nature. Even when
caused by the absorption of the carbonate or other salt of ammonia, or
an infusion of meat, the process seems to be of exactly the same
nature. The protoplasmic fluid must, therefore, be in a singularly
unstable condition, to be acted on by such slight and varied causes.
Physiologists believe that when a nerve is touched, and it transmits an
influence to other parts of the nervous system, a molecular change is
induced in it, though not visible to us. Therefore it is a very
interesting spectacle to watch the effects on the cells of a gland, of
the pressure of a bit of hair, weighing only 1/78700 of a grain and
largely supported by the dense secretion, for this excessively slight
pressure soon causes a visible change in the protoplasm, which change
is transmitted down the whole length of the tentacle, giving it at last
a mottled appearance, distinguishable even by the naked eye.

In the fourth chapter it was shown that leaves placed for a short time
in water at a temperature of 110o Fahr. (43o.3 Cent.) become somewhat
inflected; they are thus also rendered more sensitive to the action
[page 267] of meat than they were before. If exposed to a temperature
of between 115o and 125o(46o.1-51o.6 Cent.), they are quickly
inflected, and their protoplasm undergoes aggregation; when afterwards
placed in cold water, they re-expand. Exposed to 130o (54o.4 Cent.), no
inflection immediately occurs, but the leaves are only temporarily
paralysed, for on being left in cold water, they often become inflected
and afterwards re-expand. In one leaf thus treated, I distinctly saw
the protoplasm in movement. In other leaves, treated in the same
manner, and then immersed in a solution of carbonate of ammonia, strong
aggregation ensued. Leaves placed in cold water, after an exposure to
so high a temperature as 145o (62o.7 Cent.), sometimes become slightly,
though slowly, inflected; and afterwards have the contents of their
cells strongly aggregated by carbonate of ammonia. But the duration of
the immersion is an important element, for if left in water at 145o
(62o.7 Cent.), or only at 140o (60o Cent.), until it becomes cool, they
are killed, and the contents of the glands are rendered white and
opaque. This latter result seems to be due to the coagulation of the
albumen, and was almost always caused by even a short exposure to 150o
(65o.5 Cent.); but different leaves, and even the separate cells in the
same tentacle, differ considerably in their power of resisting heat.
Unless the heat has been sufficient to coagulate the albumen, carbonate
of ammonia subsequently induces aggregation.

In the fifth chapter, the results of placing drops of various
nitrogenous and non-nitrogenous organic fluids on the discs of leaves
were given, and it was shown that they detect with almost unerring
certainty the presence of nitrogen. A decoction of green peas or of
fresh cabbage-leaves acts almost as powerfully as an infusion of raw
meat; whereas an infusion of cabbage- [page 268] leaves made by keeping
them for a long time in merely warm water is far less efficient. A
decoction of grass-leaves is less powerful than one of green peas or
cabbage-leaves.

These results led me to inquire whether Drosera possessed the power of
dissolving solid animal matter. The experiments proving that the leaves
are capable of true digestion, and that the glands absorb the digested
matter, are given in detail in the sixth chapter. These are, perhaps,
the most interesting of all my observations on Drosera, as no such
power was before distinctly known to exist in the vegetable kingdom. It
is likewise an interesting fact that the glands of the disc, when
irritated, should transmit some influence to the glands of the exterior
tentacles, causing them to secrete more copiously and the secretion to
become acid, as if they had been directly excited by an object placed
on them. The gastric juice of animals contains, as is well known, an
acid and a ferment, both of which are indispensable for digestion, and
so it is with the secretion of Drosera. When the stomach of an animal
is mechanically irritated, it secretes an acid, and when particles of
glass or other such objects were placed on the glands of Drosera, the
secretion, and that of the surrounding and untouched glands, was
increased in quantity and became acid. But, according to Schiff, the
stomach of an animal does not secrete its proper ferment, pepsin, until
certain substances, which he calls peptogenes, are absorbed; and it
appears from my experiments that some matter must be absorbed by the
glands of Drosera before they secrete their proper ferment.  That the
secretion does contain a ferment which acts only in the presence of an
acid on solid animal matter, was clearly proved by adding minute doses
of [page 269] an alkali, which entirely arrested the process of
digestion, this immediately recommencing as soon as the alkali was
neutralised by a little weak hydrochloric acid. From trials made with a
large number of substances, it was found that those which the secretion
of Drosera dissolves completely, or partially, or not at all, are acted
on in exactly the same manner by gastric juice. We may, therefore,
conclude that the ferment of Drosera is closely analogous to, or
identical with, the pepsin of animals.

The substances which are digested by Drosera act on the leaves very
differently. Some cause much more energetic and rapid inflection of the
tentacles, and keep them inflected for a much longer time, than do
others. We are thus led to believe that the former are more nutritious
than the latter, as is known to be the case with some of these same
substances when given to animals; for instance, meat in comparison with
gelatine. As cartilage is so tough a substance and is so little acted
on by water, its prompt dissolution by the secretion of Drosera, and
subsequent absorption is, perhaps, one of the most striking cases. But
it is not really more remarkable than the digestion of meat, which is
dissolved by this secretion in the same manner and by the same stages
as by gastric juice. The secretion dissolves bone, and even the enamel
of teeth, but this is simply due to the large quantity of acid
secreted, owing, apparently, to the desire of the plant for phosphorus.
In the case of bone, the ferment does not come into play until all the
phosphate of lime has been decomposed and free acid is present, and
then the fibrous basis is quickly dissolved. Lastly, the secretion
attacks and dissolves matter out of living seeds, which it sometimes
kills, or injures, as shown by the diseased state [page 270] of the
seedlings. It also absorbs matter from pollen, and from fragments of
leaves.

The seventh chapter was devoted to the action of the salts of ammonia.
These all cause the tentacles, and often the blade of the leaf, to be
inflected, and the protoplasm to be aggregated. They act with very
different power; the citrate being the least powerful, and the
phosphate, owing, no doubt, to the presence of phosphorus and nitrogen,
by far the most powerful. But the relative efficiency of only three
salts of ammonia was carefully determined, namely the carbonate,
nitrate, and phosphate. The experiments were made by placing
half-minims (.0296 ml.) of solutions of different strengths on the
discs of the leaves,--by applying a minute drop (about the 1/20 of a
minim, or .00296 ml.) for a few seconds to three or four glands,--and
by the immersion of whole leaves in a measured quantity. In relation to
these experiments it was necessary first to ascertain the effects of
distilled water, and it was found, as described in detail, that the
more sensitive leaves are affected by it, but only in a slight degree.

A solution of the carbonate is absorbed by the roots and induces
aggregation in their cells, but does not affect the leaves. The vapour
is absorbed by the glands, and causes inflection as well as
aggregation. A drop of a solution containing 1/960 of a grain (.0675
mg.) is the least quantity which, when placed on the glands of the
disc, excites the exterior tentacles to bend inwards. But a minute
drop, containing 1/14400 of a grain (.00445 mg.), if applied for a few
seconds to the secretion surrounding a gland, causes the inflection of
the same tentacle.  When a highly sensitive leaf is immersed in a
solution, and there is ample time for absorption, the 1/268800 of a
grain [page 271] (.00024 mg.) is sufficient to excite a single tentacle
into movement.

The nitrate of ammonia induces aggregation of the protoplasm much less
quickly than the carbonate, but is more potent in causing inflection. A
drop containing 1/2400 of a grain (.027 mg.) placed on the disc acts
powerfully on all the exterior tentacles, which have not themselves
received any of the solution; whereas a drop with 1/2800 of a grain
caused only a few of these tentacles to bend, but affected rather more
plainly the blade. A minute drop applied as before, and containing
1/28800 of a grain (.0025 mg.), caused the tentacle bearing this gland
to bend. By the immersion of whole leaves, it was proved that the
absorption by a single gland of 1/691200 of a grain (.0000937 mg.) was
sufficient to set the same tentacle into movement.

The phosphate of ammonia is much more powerful than the nitrate. A drop
containing 1/3840 of a grain (.0169 mg.) placed on the disc of a
sensitive leaf causes most of the exterior tentacles to be inflected,
as well as the blade of the leaf. A minute drop containing 1/153600 of
a grain (.000423 mg.), applied for a few seconds to a gland, acts, as
shown by the movement of the tentacle. When a leaf is immersed in
thirty minims (1.7748 ml.) of a solution of one part by weight of the
salt to 21,875,000 of water, the absorption by a gland of only the
1/19760000 of a grain (.00000328 mg.), that is, about the
one-twenty-millionth of a grain, is sufficient to cause the tentacle
bearing this gland to bend to the centre of the leaf. In this
experiment, owing to the presence of the water of crystallisation, less
than the one-thirty-millionth of a grain of the efficient elements
could have been absorbed. There is nothing remarkable in such minute
quantities being absorbed by the glands, [page 272] for all
physiologists admit that the salts of ammonia, which must be brought in
still smaller quantity by a single shower of rain to the roots, are
absorbed by them. Nor is it surprising that Drosera should be enabled
to profit by the absorption of these salts, for yeast and other low
fungoid forms flourish in solutions of ammonia, if the other necessary
elements are present.  But it is an astonishing fact, on which I will
not here again enlarge, that so inconceivably minute a quantity as the
one-twenty-millionth of a grain of phosphate of ammonia should induce
some change in a gland of Drosera, sufficient to cause a motor impulse
to be sent down the whole length of the tentacle; this impulse exciting
movement often through an angle of above 180o. I know not whether to be
most astonished at this fact, or that the pressure of a minute bit of
hair, supported by the dense secretion, should quickly cause
conspicuous movement. Moreover, this extreme sensitiveness, exceeding
that of the most delicate part of the human body, as well as the power
of transmitting various impulses from one part of the leaf to another,
have been acquired without the intervention of any nervous system.

As few plants are at present known to possess glands specially adapted
for absorption, it seemed worth while to try the effects on Drosera of
various other salts, besides those of ammonia, and of various acids.
Their action, as described in the eighth chapter, does not correspond
at all strictly with their chemical affinities, as inferred from the
classification commonly followed. The nature of the base is far more
influential than that of the acid; and this is known to hold good with
animals. For instance, nine salts of sodium all caused well-marked
inflection, and none of them were poisonous in small doses; whereas
seven of the nine corre- [page 273] sponding salts of potassium
produced no effect, two causing slight inflection. Small doses,
moreover, of some of the latter salts were poisonous. The salts of
sodium and potassium, when injected into the veins of animals, likewise
differ widely in their action. The so-called earthy salts produce
hardly any effect on Drosera. On the other hand, most of the metallic
salts cause rapid and strong inflection, and are highly poisonous; but
there are some odd exceptions to this rule; thus chloride of lead and
zinc, as well as two salts of barium, did not cause inflection, and
were not poisonous.

Most of the acids which were tried, though much diluted (one part to
437 of water), and given in small doses, acted powerfully on Drosera;
nineteen, out of the twenty-four, causing the tentacles to be more or
less inflected. Most of them, even the organic acids, are poisonous,
often highly so; and this is remarkable, as the juices of so many
plants contain acids. Benzoic acid, which is innocuous to animals,
seems to be as poisonous to Drosera as hydrocyanic. On the other hand,
hydrochloric acid is not poisonous either to animals or to Drosera, and
induces only a moderate amount of inflection. Many acids excite the
glands to secrete an extraordinary quantity of mucus; and the
protoplasm within their cells seems to be often killed, as may be
inferred from the surrounding fluid soon becoming pink. It is strange
that allied acids act very differently: formic acid induces very slight
inflection, and is not poisonous; whereas acetic acid of the same
strength acts most powerfully and is poisonous.  Lactic acid is also
poisonous, but causes inflection only after a considerable lapse of
time.  Malic acid acts slightly, whereas citric and tartaric acids
produce no effect.  [page 274]

In the ninth chapter the effects of the absorption of various alkaloids
and certain other substances were described. Although some of these are
poisonous, yet as several, which act powerfully on the nervous system
of animals, produce no effect on Drosera, we may infer that the extreme
sensibility of the glands, and their power of transmitting an influence
to other parts of the leaf, causing movement, or modified secretion, or
aggregation, does not depend on the presence of a diffused element,
allied to nerve-tissue. One of the most remarkable facts is that long
immersion in the poison of the cobra-snake does not in the least check,
but rather stimulates, the spontaneous movements of the protoplasm in
the cells of the tentacles. Solutions of various salts and acids behave
very differently in delaying or in quite arresting the subsequent
action of a solution of phosphate of ammonia. Camphor dissolved in
water acts as a stimulant, as do small doses of certain essential oils,
for they cause rapid and strong inflection. Alcohol is not a stimulant.
The vapours of camphor, alcohol, chloroform, sulphuric and nitric
ether, are poisonous in moderately large doses, but in small doses
serve as narcotics or, anaesthetics, greatly delaying the subsequent
action of meat. But some of these vapours also act as stimulants,
exciting rapid, almost spasmodic movements in the tentacles. Carbonic
acid is likewise a narcotic, and retards the aggregation of the
protoplasm when carbonate of ammonia is subsequently given. The first
access of air to plants which have been immersed in this gas sometimes
acts as a stimulant and induces movement. But, as before remarked, a
special pharmacopoeia would be necessary to describe the diversified
effects of various substances on the leaves of Drosera.

In the tenth chapter it was shown that the sensitive- [page 275] ness
of the leaves appears to be wholly confined to the glands and to the
immediately underlying cells. It was further shown that the motor
impulse and other forces or influences, proceeding from the glands when
excited, pass through the cellular tissue, and not along the
fibro-vascular bundles. A gland sends its motor impulse with great
rapidity down the pedicel of the same tentacle to the basal part which
alone bends. The impulse, then passing onwards, spreads on all sides to
the surrounding tentacles, first affecting those which stand nearest
and then those farther off. But by being thus spread out, and from the
cells of the disc not being so much elongated as those of the
tentacles, it loses force, and here travels much more slowly than down
the pedicels. Owing also to the direction and form of the cells, it
passes with greater ease and celerity in a longitudinal than in a
transverse line across the disc. The impulse proceeding from the glands
of the extreme marginal tentacles does not seem to have force enough to
affect the adjoining tentacles; and this may be in part due to their
length. The impulse from the glands of the next few inner rows spreads
chiefly to the tentacles on each side and towards the centre of the
leaf; but that proceeding from the glands of the shorter tentacles on
the disc radiates almost equally on all sides.

When a gland is strongly excited by the quantity or quality of the
substance placed on it, the motor impulse travels farther than from one
slightly excited; and if several glands are simultaneously excited, the
impulses from all unite and spread still farther. As soon as a gland is
excited, it discharges an impulse which extends to a considerable
distance; but afterwards, whilst the gland is secreting and absorbing,
the impulse suffices only to keep the same tentacle [page 276]
inflected; though the inflection may last for many days.

If the bending place of a tentacle receives an impulse from its own
gland, the movement is always towards the centre of the leaf; and so it
is with all the tentacles, when their glands are excited by immersion
in a proper fluid. The short ones in the middle part of the disc must
be excepted, as these do not bend at all when thus excited. On the
other hand, when the motor impulse comes from one side of the disc, the
surrounding tentacles, including the short ones in the middle of the
disc, all bend with precision towards the point of excitement, wherever
this may be seated. This is in every way a remarkable phenomenon; for
the leaf falsely appears as if endowed with the senses of an animal. It
is all the more remarkable, as when the motor impulse strikes the base
of a tentacle obliquely with respect to its flattened surface, the
contraction of the cells must be confined to one, two, or a very few
rows at one end. And different sides of the surrounding tentacles must
be acted on, in order that all should bend with precision to the point
of excitement.

The motor impulse, as it spreads from one or more glands across the
disc, enters the bases of the surrounding tentacles, and immediately
acts on the bending place. It does not in the first place proceed up
the tentacles to the glands, exciting them to reflect back an impulse
to their bases. Nevertheless, some influence is sent up to the glands,
as their secretion is soon increased and rendered acid; and then the
glands, being thus excited, send back some other influence (not
dependent on increased secretion, nor on the inflection of the
tentacles), causing the protoplasm to aggregate in cell beneath cell.
This may [page 277] be called a reflex action, though probably very
different from that proceeding from the nerve-ganglion of an animal;
and it is the only known case of reflex action in the vegetable
kingdom.

About the mechanism of the movements and the nature of the motor
impulse we know very little. During the act of inflection fluid
certainly travels from one part to another of the tentacles. But the
hypothesis which agrees best with the observed facts is that the motor
impulse is allied in nature to the aggregating process; and that this
causes the molecules of the cell-walls to approach each other, in the
same manner as do the molecules of the protoplasm within the cells; so
that the cell-walls contract. But some strong objections may be urged
against this view. The re-expansion of the tentacles is largely due to
the elasticity of their outer cells, which comes into play as soon as
those on the inner side cease contracting with prepotent force; but we
have reason to suspect that fluid is continually and slowly attracted
into the outer cells during the act of re-expansion, thus increasing
their tension.

I have now given a brief recapitulation of the chief points observed by
me, with respect to the structure, movements, constitution, and habits
of Drosera rotundifolia; and we see how little has been made out in
comparison with what remains unexplained and unknown.  [page 278]



                          CHAPTER XII.

ON THE STRUCTURE AND MOVEMENTS OF SOME OTHER SPECIES OF DROSERA.

Drosera anglica--Drosera intermedia--Drosera capensis--Drosera
spathulata--Drosera filiformis--Drosera binata--Concluding remarks.

I EXAMINED six other species of Drosera, some of them inhabitants of
distant countries, chiefly for the sake of ascertaining whether they
caught insects. This seemed the more necessary as the leaves of some of
the species differ to an extraordinary degree in shape from the rounded
ones of Drosera rotundifolia. In functional powers, however, they
differ very little.

[Drosera anglica (Hudson).*--The leaves of this species, which was sent
to me from Ireland, are much elongated, and gradually widen from the
footstalk to the bluntly pointed apex. They stand almost erect, and
their blades sometimes exceed 1 inch in length, whilst their breadth is
only the 1/5 of an inch. The glands of all the tentacles have the same
structure, so that the extreme marginal ones do not differ from the
others, as in the case of Drosera rotundifolia.  When they are
irritated by being roughly touched, or by the pressure of minute
inorganic particles, or by contact with animal matter, or by the
absorption of carbonate of ammonia, the tentacles become inflected; the
basal portion being the chief seat of movement. Cutting or pricking the
blade of the leaf did not excite any movement. They frequently capture
insects, and the glands of the inflected tentacles pour forth much acid
secretion. Bits of roast meat were placed on some glands, and the
tentacles began to move in 1 m. or

* Mrs. Treat has given an excellent account in 'The American
Naturalist,' December 1873, p.  705, of Drosera longifolia (which is a
synonym in part of Drosera anglica), of Drosera rotundifolia and
filiformis.  [page 279]

1 m. 30 s.; and in 1 hr. 10 m. reached the centre. Two bits of boiled
cork, one of boiled thread, and two of coal-cinders taken from the
fire, were placed, by the aid of an instrument which had been immersed
in boiling water, on five glands; these superfluous precautions having
been taken on account of M. Ziegler's statements. One of the particles
of cinder caused some inflection in 8 hrs. 45 m., as did after 23 hrs.
the other particle of cinder, the bit of thread, and both bits of cork.
Three glands were touched half a dozen times with a needle; one of the
tentacles became well inflected in 17 m., and re-expanded after 24
hrs.; the two others never moved. The homogeneous fluid within the
cells of the tentacles undergoes aggregation after these have become
inflected; especially if given a solution of carbonate of ammonia; and
I observed the usual movements in the masses of protoplasm. In one
case, aggregation ensued in 1 hr. 10 m. after a tentacle had carried a
bit of meat to the centre. From these facts it is clear that the
tentacles of Drosera anglica behave like those of Drosera
rotundifolia.

If an insect is placed on the central glands, or has been naturally
caught there, the apex of the leaf curls inwards. For instance, dead
flies were placed on three leaves near their bases, and after 24 hrs.
the previously straight apices were curled completely over, so as to
embrace and conceal the flies; they had therefore moved through an
angle of 180o. After three days the apex of one leaf, together with the
tentacles, began to re-expand. But as far as I have seen-- and I made
many trials--the sides of the leaf are never inflected, and this is the
one functional difference between this species and Drosera
rotundifolia.

Drosera intermedia (Hayne).--This species is quite as common in some
parts of England as Drosera rotundifolia. It differs from Drosera
anglica, as far as the leaves are concerned, only in their smaller
size, and in their tips being generally a little reflexed. They capture
a large number of insects. The tentacles are excited into movement by
all the causes above specified; and aggregation ensues, with movement
of the protoplasmic masses. I have seen, through a lens, a tentacle
beginning to bend in less than a minute after a particle of raw meat
had been placed on the gland. The apex of the leaf curls over an
exciting object as in the case of Drosera anglica. Acid secretion is
copiously poured over captured insects. A leaf which had embraced a fly
with all its tentacles re-expanded after nearly three days.

Drosera capensis.--This species, a native of the Cape of Good Hope, was
sent to me by Dr.  Hooker. The leaves are elongated, slightly concave
along the middle and taper towards the apex, [page 280] which is
bluntly pointed and reflexed. They rise from an almost woody axis, and
their greatest peculiarity consists in their foliaceous green
footstalks, which are almost as broad and even longer than the
gland-bearing blade. This species, therefore, probably draws more
nourishment from the air, and less from captured insects, than the
other species of the genus.  Nevertheless, the tentacles are crowded
together on the disc, and are extremely numerous; those on the margins
being much longer than the central ones. All the glands have the same
form; their secretion is extremely viscid and acid.

The specimen which I examined had only just recovered from a weak state
of health. This may account for the tentacles moving very slowly when
particles of meat were placed on the glands, and perhaps for my never
succeeding in causing any movement by repeatedly touching them with a
needle. But with all the species of the genus this latter stimulus is
the least effective of any. Particles of glass, cork, and coal-cinders,
were placed on the glands of six tentacles; and one alone moved after
an interval of 2 hrs. 30 m. Nevertheless, two glands were extremely
sensitive to very small doses of the nitrate of ammonia, namely to
about 1/20 of a minim of a solution (one part to 5250 of water),
containing only 1/115200 of a grain (.000562 mg.) of the salt.
Fragments of flies were placed on two leaves near their tips, which
became incurved in 15 hrs. A fly was also placed in the middle of the
leaf; in a few hours the tentacles on each side embraced it, and in 8
hrs. the whole leaf directly beneath the fly was a little bent
transversely. By the next morning, after 23 hrs., the leaf was curled
so completely over that the apex rested on the upper end of the
footstalk. In no case did the sides of the leaves become inflected. A
crushed fly was placed on the foliaceous footstalk, but produced no
effect.

Drosera spathulata (sent to me by Dr. Hooker).--I made only a few
observations on this Australian species, which has long, narrow leaves,
gradually widening towards their tips. The glands of the extreme
marginal tentacles are elongated and differ from the others, as in the
case of Drosera rotundifolia. A fly was placed on a leaf, and in 18
hrs. it was embraced by the adjoining tentacles. Gum-water dropped on
several leaves produced no effect. A fragment of a leaf was immersed in
a few drops of a solution of one part of carbonate of ammonia to 146 of
water; all the glands were instantly blackened; the process of
aggregation could be seen travelling rapidly down the cells of the
tentacles; and the granules of protoplasm soon united into spheres and
variously shaped masses, which displayed the usual move- [page 281]
ments. Half a minim of a solution of one part of nitrate of ammonia to
146 of water was next placed on the centre of a leaf; after 6 hrs. some
marginal tentacles on both sides were inflected, and after 9 hrs. they
met in the centre. The lateral edges of the leaf also became incurved,
so that it formed a half-cylinder; but the apex of the leaf in none of
my few trials was inflected. The above dose of the nitrate (viz. 1/320
of a grain, or .202 mg.) was too powerful, for in the course of 23 hrs.
the leaf died.

Drosera filiformis.--This North American species grows in such
abundance in parts of New Jersey as almost to cover the ground. It
catches, according to Mrs. Treat,* an extraordinary number of small and
large insects, even great flies of the genus Asilus, moths, and
butterflies.  The specimen which I examined, sent me by Dr. Hooker, had
thread-like leaves, from 6 to 12 inches in length, with the upper
surface convex and the lower flat and slightly channelled.  The whole
convex surface, down to the roots--for there is no distinct
footstalk--is covered with short gland-bearing tentacles, those on the
margins being the longest and reflexed. Bits of meat placed on the
glands of some tentacles caused them to be slightly inflected in 20 m.;
but the plant was not in a vigorous state. After 6 hrs. they moved
through an angle of 90o, and in 24 hrs. reached the centre. The
surrounding tentacles by this time began to curve inwards.  Ultimately
a large drop of extremely viscid, slightly acid secretion was poured
over the meat from the united glands. Several other glands were touched
with a little saliva, and the tentacles became incurved in under 1 hr.,
and re-expanded after 18 hrs. Particles of glass, cork, cinders,
thread, and gold-leaf, were placed on numerous glands on two leaves; in
about 1 hr. four tentacles became curved, and four others after an
additional interval of 2 hrs. 30 m.  I never once succeeded in causing
any movement by repeatedly touching the glands with a needle; and Mrs.
Treat made similar trials for me with no success. Small flies were
placed on several leaves near their tips, but the thread-like blade
became only on one occasion very slightly bent, directly beneath the
insect. Perhaps this indicates that the blades of vigorous plants would
bend over captured insects, and Dr. Canby informs me that this is the
case; but the movement cannot be strongly pronounced, as it was not
observed by Mrs. Treat.

Drosera binata (or dichotoma).--I am much indebted to Lady

* 'American Naturalist,' December 1873, page 705.  [page 282]

Dorothy Nevill for a fine plant of this almost gigantic Australian
species, which differs in some interesting points from those previously
described. In this specimen the rush-like footstalks of the leaves were
20 inches in length. The blade bifurcates at its junction with the
footstalk, and twice or thrice afterwards, curling about in an
irregular manner. It is narrow, being only 3/20 of an inch in breadth.
One blade was 7 1/2 inches long, so that the entire leaf, including the
footstalk, was above 27 inches in length. Both surfaces are slightly
hollowed out. The upper surface is covered with tentacles arranged in
alternate rows; those in the middle being short and crowded together,
those towards the margins longer, even twice or thrice as long as the
blade is broad. The glands of the exterior tentacles are of a much
darker red than those of the central ones. The pedicels of all are
green. The apex of the blade is attenuated, and bears very long
tentacles. Mr. Copland informs me that the leaves of a plant which he
kept for some years were generally covered with captured insects before
they withered.

The leaves do not differ in essential points of structure or of
function from those of the previously described species. Bits of meat
or a little saliva placed on the glands of the exterior tentacles
caused well-marked movement in 3 m., and particles of glass acted in 4
m.  The tentacles with the latter particles re-expanded after 22 hrs. A
piece of leaf immersed in a few drops of a solution of one part of
carbonate of ammonia to 437 of water had all the glands blackened and
all the tentacles inflected in 5 m. A bit of raw meat, placed on
several glands in the medial furrow, was well clasped in 2 hrs. 10 m.
by the marginal tentacles on both sides. Bits of roast meat and small
flies did not act quite so quickly; and albumen and fibrin still less
quickly. One of the bits of meat excited so much secretion (which is
always acid) that it flowed some way down the medial furrow, causing
the inflection of the tentacles on both sides as far as it extended.
Particles of glass placed on the glands in the medial furrow did not
stimulate them sufficiently for any motor impulse to be sent to the
outer tentacles. In no case was the blade of the leaf, even the
attenuated apex, at all inflected.

On both the upper and lower surface of the blade there are numerous
minute, almost sessile glands, consisting of four, eight, or twelve
cells. On the lower surface they are pale purple, on the upper
greenish. Nearly similar organs occur on the foot-stalks, but they are
smaller and often in a shrivelled condition. The minute glands on the
blade can absorb rapidly: thus, a piece of leaf was immersed in a
solution of one part of carbonate [page 283] of ammonia to 218 of water
(1 gr. to 2 oz.), and in 5 m. they were all so much darkened as to be
almost black, with their contents aggregated. They do not, as far as I
could observe, secrete spontaneously; but in between 2 and 3 hrs. after
a leaf had been rubbed with a bit of raw meat moistened with saliva,
they seemed to be secreting freely; and this conclusion was afterwards
supported by other appearances. They are, therefore, homologous with
the sessile glands hereafter to be described on the leaves of Dionaea
and Drosophyllum. In this latter genus they are associated, as in the
present case, with glands which secrete spontaneously, that is, without
being excited.

Drosera binata presents another and more remarkable peculiarity,
namely, the presence of a few tentacles on the backs of the leaves,
near their margins. These are perfect in structure; spiral vessels run
up their pedicels; their glands are surrounded by drops of viscid
secretion, and they have the power of absorbing. This latter fact was
shown by the glands immediately becoming black, and the protoplasm
aggregated, when a leaf was placed in a little solution of one part of
carbonate of ammonia to 437 of water. These dorsal tentacles are short,
not being nearly so long as the marginal ones on the upper surface;
some of them are so short as almost to graduate into the minute sessile
glands. Their presence, number, and size, vary on different leaves, and
they are arranged rather irregularly. On the back of one leaf I counted
as many as twenty-one along one side.

These dorsal tentacles differ in one important respect from those on
the upper surface, namely, in not possessing any power of movement, in
whatever manner they may be stimulated. Thus, portions of four leaves
were placed at different times in solutions of carbonate of ammonia
(one part to 437 or 218 of water), and all the tentacles on the upper
surface soon became closely inflected; but the dorsal ones did not
move, though the leaves were left in the solution for many hours, and
though their glands from their blackened colour had obviously absorbed
some of the salt. Rather young leaves should be selected for such
trials, for the dorsal tentacles, as they grow old and begin to wither,
often spontaneously incline towards the middle of the leaf. If these
tentacles had possessed the power of movement, they would not have been
thus rendered more serviceable to the plant; for they are not long
enough to bend round the margin of the leaf so as to reach an insect
caught on the upper surface, Nor would it have been of any use if these
tentacles could have [page 284] moved towards the middle of the lower
surface, for there are no viscid glands there by which insects can be
caught. Although they have no power of movement, they are probably of
some use by absorbing animal matter from any minute insect which may be
caught by them, and by absorbing ammonia from the rain-water. But their
varying presence and size, and their irregular position, indicate that
they are not of much service, and that they are tending towards
abortion. In a future chapter we shall see that Drosophyllum, with its
elongated leaves, probably represents the condition of an early
progenitor of the genus Drosera; and none of the tentacles of
Drosophyllum, neither those on the upper nor lower surface of the
leaves, are capable of movement when excited, though they capture
numerous insects, which serve as nutriment. Therefore it seems that
Drosera binata has retained remnants of certain ancestral
characters--namely a few motionless tentacles on the backs of the
leaves, and fairly well developed sessile glands--which have been lost
by most or all of the other species of the genus.]

Concluding Remarks.--From what we have now seen, there can be little
doubt that most or probably all the species of Drosera are adapted for
catching insects by nearly the same means. Besides the two Australian
species above described, it is said* that two other species from this
country, namely Drosera pallida and Drosera sulphurea, "close their
leaves upon insects with "great rapidity: and the same phenomenon is
mani-"fested by an Indian species, D. lunata, and by several "of those
of the Cape of Good Hope, especially by "D. trinervis." Another
Australian species, Drosera heterophylla (made by Lindley into a
distinct genus, Sondera) is remarkable from its peculiarly shaped
leaves, but I know nothing of its power of catching insects, for I have
seen only dried specimens. The leaves form minute flattened cups, with
the footstalks attached not to one margin, but to the bottom. The

* 'Gardener's Chronicle,' 1874, p. 209.  [page 285]

inner surface and the edges of the cups are studded with tentacles,
which include fibro-vascular bundles, rather different from those seen
by me in any other species; for some of the vessels are barred and
punctured, instead of being spiral. The glands secrete copiously,
judging from the quantity of dried secretion adhering to them.  [page
286]



                         CHAPTER XIII.

                       DIONAEA MUSCIPULA.

Structure of the leaves--Sensitiveness of the filaments--Rapid movement
of the lobes caused by irritation of the filaments--Glands, their power
of secretion--Slow movement caused by the absorption of animal
matter--Evidence of absorption from the aggregated condition of the
glands--Digestive power of the secretion--Action of chloroform, ether,
and hydrocyanic acid- -The manner in which insects are captured--Use of
the marginal spikes--Kinds of insects captured--The transmission of the
motor impulse and mechanism of the movements-- Re-expansion of the
lobes.

THIS plant, commonly called Venus' fly-trap, from the rapidity and
force of its movements, is one of the most wonderful in the world.* It
is a member of the small family of the Droseraceae, and is found only
in the eastern part of North Carolina, growing in damp situations. The
roots are small; those of a moderately fine plant which I examined
consisted of two branches about 1 inch in length, springing from a
bulbous enlargement. They probably serve, as in the case of Drosera,
solely for the absorption of water; for a gardener, who has been very
successful in the cultivation of this plant, grows it, like an
epiphytic orchid, in well-drained damp moss without any soil.  The form
of the bilobed leaf, with its foliaceous footstalk, is shown in the
accompanying drawing (fig. 12).

* Dr. Hooker, in his address to the British Association at Belfast,
1874, has given so full an historical account of the observations which
have been published on the habits of this plant, that it would be
superfluous on my part to repeat them.

  'Gardener's Chronicle,' 1874, p. 464.  [page 287]

The two lobes stand at rather less than a right angle to each other.
Three minute pointed processes or filaments, placed triangularly,
project from the upper surfaces of both; but I have seen two leaves
with four filaments on each side, and another with only two. These
filaments are remarkable from their extreme sensitiveness to a touch,
as shown not by their own movement, but by that of the lobes. The
margins of the leaf are prolonged into sharp rigid projections which I
will call spikes, into each of which a bundle

FIG. 12.  (Dionaea muscipula.) Leaf viewed laterally in its expanded
state.

of spiral vessels enters. The spikes stand in such a position that,
when the lobes close, they inter-lock like the teeth of a rat-trap. The
midrib of the leaf, on the lower side, is strongly developed and
prominent.

The upper surface of the leaf is thickly covered, excepting towards the
margins, with minute glands of a reddish or purplish colour, the rest
of the leaf being green. There are no glands on the spikes, or on the
foliaceous footstalk, The glands are formed of from [page 288] twenty
to thirty polygonal cells, filled with purple fluid. Their upper
surface is convex. They stand on very short pedicels, into which spiral
vessels do not enter, in which respect they differ from the tentacles
of Drosera. They secrete, but only when excited by the absorption of
certain matters; and they have the power of absorption. Minute
projections, formed of eight divergent arms of a reddish-brown or
orange colour, and appearing under the microscope like elegant little
flowers, are scattered in considerable numbers over the foot-stalk, the
backs of the leaves, and the spikes, with a few on the upper surface of
the lobes. These octofid projections are no doubt homologous with the
papillae on the leaves of Drosera rotundifolia.  There are also a few
very minute, simple, pointed hairs, about 7/12000 (.0148 mm.) of an
inch in length on the backs of the leaves.

The sensitive filaments are formed of several rows of elongated cells,
filled with purplish fluid. They are a little above the 1/20 of an inch
in length; are thin and delicate, and taper to a point. I examined the
bases of several, making sections of them, but no trace of the entrance
of any vessel could be seen. The apex is sometimes bifid or even
trifid, owing to a slight separation between the terminal pointed
cells. Towards the base there is constriction, formed of broader cells,
beneath which there is an articulation, supported on an enlarged base,
consisting of differently shaped polygonal cells. As the filaments
project at right angles to the surface of the leaf, they would have
been liable to be broken whenever the lobes closed together, had it not
been for the articulation which allows them to bend flat down.

These filaments, from their tips to their bases, are exquisitely
sensitive to a momentary touch. It is scarcely [page 289] possible to
touch them ever so lightly or quickly with any hard object without
causing the lobes to close. A piece of very delicate human hair, 2 1/2
inches in length, held dangling over a filament, and swayed to and fro
so as to touch it, did not excite any movement. But when a rather thick
cotton thread of the same length was similarly swayed, the lobes
closed. Pinches of fine wheaten flour, dropped from a height, produced
no effect. The above-mentioned hair was then fixed into a handle, and
cut off so that 1 inch projected; this length being sufficiently rigid
to support itself in a nearly horizontal line. The extremity was then
brought by a slow movement laterally into contact with the tip of a
filament, and the leaf instantly closed. On another occasion two or
three touches of the same kind were necessary before any movement
ensued. When we consider how flexible a fine hair is, we may form some
idea how slight must be the touch given by the extremity of a piece, 1
inch in length, moved slowly.

Although these filaments are so sensitive to a momentary and delicate
touch, they are far less sensitive than the glands of Drosera to
prolonged pressure. Several times I succeeded in placing on the tip of
a filament, by the aid of a needle moved with extreme slowness, bits of
rather thick human hair, and these did not excite movement, although
they were more than ten times as long as those which caused the
tentacles of Drosera to bend; and although in this latter case they
were largely supported by the dense secretion. On the other hand, the
glands of Drosera may be struck with a needle or any hard object, once,
twice, or even thrice, with considerable force, and no movement ensues.
This singular difference in the nature of the sensitiveness of the
filaments of Dionaea and of [page 290] the glands of Drosera evidently
stands in relation to the habits of the two plants. If a minute insect
alights with its delicate feet on the glands of Drosera, it is caught
by the viscid secretion, and the slight, though prolonged pressure,
gives notice of the presence of prey, which is secured by the slow
bending of the tentacles. On the other hand, the sensitive filaments of
Dionaea are not viscid, and the capture of insects can be assured only
by their sensitiveness to a momentary touch, followed by the rapid
closure of the lobes.

As just stated, the filaments are not glandular, and do not secrete.
Nor have they the power of absorption, as may be inferred from drops of
a solution of carbonate of ammonia (one part to 146 of water), placed
on two filaments, not producing any effect on the contents of their
cells, nor causing the lobes to close, When, however, a small portion
of a leaf with an attached filament was cut off and immersed in the
same solution, the fluid within the basal cells became almost instantly
aggregated into purplish or colourless, irregularly shaped masses of
matter. The process of aggregation gradually travelled up the filaments
from cell to cell to their extremities, that is in a reverse course to
what occurs in the tentacles of Drosera when their glands have been
excited. Several other filaments were cut off close to their bases, and
left for 1 hr. 30 m. in a weaker solution of one part of the carbonate
to 218 of water, and this caused aggregation in all the cells,
commencing as before at the bases of the filaments.

Long immersion of the filaments in distilled water likewise causes
aggregation. Nor is it rare to find the contents of a few of the
terminal cells in a spontaneously aggregated condition.  The aggregated
[page 291] masses undergo incessant slow changes of form, uniting and
again separating; and some of them apparently revolve round their own
axes. A current of colourless granular protoplasm could also be seen
travelling round the walls of the cells. This current ceases to be
visible as soon as the contents are well aggregated; but it probably
still continues, though no longer visible, owing to all the granules in
the flowing layer having become united with the central masses. In all
these respects the filaments of Dionaea behave exactly like the
tentacles of Drosera.

Notwithstanding this similarity there is one remarkable difference. The
tentacles of Drosera, after their glands have been repeatedly touched,
or a particle of any kind has been placed on them, become inflected and
strongly aggregated. No such effect is produced by touching the
filaments of Dionaea; I compared, after an hour or two, some which had
been touched and some which had not, and others after twenty-five
hours, and there was no difference in the contents of the cells. The
leaves were kept open all the time by clips; so that the filaments were
not pressed against the opposite lobe.

Drops of water, or a thin broken stream, falling from a height on the
filaments, did not cause the blades to close; though these filaments
were afterwards proved to be highly sensitive. No doubt, as in the case
of Drosera, the plant is indifferent to the heaviest shower of rain.
Drops of a solution of a half an ounce of sugar to a fluid ounce of
water were repeatedly allowed to fall from a height on the filaments,
but produced no effect, unless they adhered to them.  Again, I blew
many times through a fine pointed tube with my utmost force against the
filaments without any effect; such blowing being received [page 292]
with as much indifference as no doubt is a heavy gale of wind. We thus
see that the sensitiveness of the filaments is of a specialised nature,
being related to a momentary touch rather than to prolonged pressure;
and the touch must not be from fluids, such as air or water, but from
some solid object.

Although drops of water and of a moderately strong solution of sugar,
falling on the filaments, does not excite them, yet the immersion of a
leaf in pure water sometimes caused the lobes to close. One leaf was
left immersed for 1 hr. 10 m., and three other leaves for some minutes,
in water at temperatures varying between 59o and 65o (15o to 18o.3
Cent.) without any effect. One, however, of these four leaves, on being
gently withdrawn from the water, closed rather quickly. The three other
leaves were proved to be in good condition, as they closed when their
filaments were touched. Nevertheless two fresh leaves on being dipped
into water at 75o and 62 1/2o (23o.8 and 16o.9 Cent.) instantly closed.
These were then placed with their footstalks in water, and after 23
hrs. partially re-expanded; on touching their filaments one of them
closed. This latter leaf after an additional 24 hrs. again re-expanded,
and now, on the filaments of both leaves being touched, both closed. We
thus see that a short immersion in water does not at all injure the
leaves, but sometimes excites the lobes to close. The movement in the
above cases was evidently not caused by the temperature of the water.
It has been shown that long immersion causes the purple fluid within
the cells of the sensitive filaments to become aggregated; and the
tentacles of Drosera are acted on in the same manner by long immersion,
often being somewhat inflected. In both cases the result is probably
due to a slight degree of exosmose.  [page 293]

I am confirmed in this belief by the effects of immersing a leaf of
Dionaea in a moderately strong solution of sugar; the leaf having been
previously left for 1 hr. 10 m. in water without any effect; for now
the lobes closed rather quickly, the tips of the marginal spikes
crossing in 2 m. 30 s., and the leaf being completely shut in 3 m.
Three leaves were then immersed in a solution of half an ounce of sugar
to a fluid ounce of water, and all three leaves closed quickly. As I
was doubtful whether this was due to the cells on the upper surface of
the lobes, or to the sensitive filaments, being acted on by exosmose,
one leaf was first tried by pouring a little of the same solution in
the furrow between the lobes over the midrib, which is the chief seat
of movement. It was left there for some time, but no movement ensued.
The whole upper surface of leaf was then painted (except close round
the bases of the sensitive filaments, which I could not do without risk
of touching them) with the same solution, but no effect was produced.
So that the cells on the upper surface are not thus affected. But when,
after many trials, I succeeded in getting a drop of the solution to
cling to one of the filaments, the leaf quickly closed. Hence we may, I
think, conclude that the solution causes fluid to pass out of the
delicate cells of the filaments by exosmose; and that this sets up some
molecular change in their contents, analogous to that which must be
produced by a touch.

The immersion of leaves in a solution of sugar affects them for a much
longer time than does an immersion in water, or a touch on the
filaments; for in these latter cases the lobes begin to re-expand in
less than a day. On the other hand, of the three leaves which were
immersed for a short time in the solution, and were then washed by
means of a syringe inserted [page 294] between the lobes, one
re-expanded after two days; a second after seven days; and the third
after nine days. The leaf which closed, owing to a drop of the solution
having adhered to one of the filaments, opened after two days.

I was surprised to find on two occasions that the heat from the rays of
the sun, concentrated by a lens on the bases of several filaments, so
that they were scorched and discoloured, did not cause any movement;
though the leaves were active, as they closed, though rather slowly,
when a filament on the opposite side was touched. On a third trial, a
fresh leaf closed after a time, though very slowly; the rate not being
increased by one of the filaments, which had not been injured, being
touched. After a day these three leaves opened, and were fairly
sensitive when the uninjured filaments were touched. The sudden
immersion of a leaf into boiling water does not cause it to close.
Judging from the analogy of Drosera, the heat in these several cases
was too great and too suddenly applied. The surface of the blade is
very slightly sensitive; It may be freely and roughly handled, without
any movement being caused. A leaf was scratched rather hard with a
needle, but did not close; but when the triangular space between the
three filaments on another leaf was similarly scratched, the lobes
closed. They always closed when the blade or midrib was deeply pricked
or cut. Inorganic bodies, even of large size, such as bits of stone,
glass, &c.--or organic bodies not containing soluble nitrogenous
matter, such as bits of wood, cork, moss,--or bodies containing soluble
nitrogenous matter, if perfectly dry, such as bits of meat, albumen,
gelatine, &c., may be long left (and many were tried) on the lobes, and
no movement is excited. The result, however, is widely different, as we
[page 295] shall presently see, if nitrogenous organic bodies which are
at all damp, are left on the lobes; for these then close by a slow and
gradual movement, very different from that caused by touching one of
the sensitive filaments. The footstalk is not in the least sensitive; a
pin may be driven through it, or it may be cut off, and no movement
follows.

The upper surface of the lobes, as already stated, is thickly covered
with small purplish, almost sessile glands. These have the power both
of secretion and absorption; but unlike those of Drosera, they do not
secrete until excited by the absorption of nitrogenous matter.  No
other excitement, as far as I have seen, produces this effect. Objects,
such as bits of wood, cork, moss, paper, stone, or glass, may be left
for a length of time on the surface of a leaf, and it remains quite
dry. Nor does it make any difference if the lobes close over such
objects. For instance, some little balls of blotting paper were placed
on a leaf, and a filament was touched; and when after 24 hrs. the lobes
began to re-open, the balls were removed by the aid of thin pincers,
and were found perfectly dry. On the other hand, if a bit of damp meat
or a crushed fly is placed on the surface of an expanded leaf, the
glands after a time secrete freely. In one such case there was a little
secretion directly beneath the meat in 4 hrs.; and after an additional
3 hrs. there was a considerable quantity both under and close round it.
In another case, after 3 hrs. 40 m., the bit of meat was quite wet. But
none of the glands secreted, excepting those which actually touched the
meat or the secretion containing dissolved animal matter.

If, however, the lobes are made to close over a bit of meat or an
insect, the result is different, for the glands over the whole surface
of the leaf now secrete copiously.  [page 296] As in this case the
glands on both sides are pressed against the meat or insect, the
secretion from the first is twice as great as when a bit of meat is
laid on the surface of one lobe; and as the two lobes come into almost
close contact, the secretion, containing dissolved animal matter,
spreads by capillary attraction, causing fresh glands on both sides to
begin secreting in a continually widening circle. The secretion is
almost colourless, slightly mucilaginous, and, judging by the manner in
which it coloured litmus paper, more strongly acid than that of
Drosera. It is so copious that on one occasion, when a leaf was cut
open, on which a small cube of albumen had been placed 45 hrs. before,
drops rolled off the leaf. On another occasion, in which a leaf with an
enclosed bit of roast meat spontaneously opened after eight days, there
was so much secretion in the furrow over the midrib that it trickled
down. A large crushed fly (Tipula) was placed on a leaf from which a
small portion at the base of one lobe had previously been cut away, so
that an opening was left; and through this, the secretion continued to
run down the footstalk during nine days,--that is, for as long a time
as it was observed. By forcing up one of the lobes, I was able to see
some distance between them, and all the glands within sight were
secreting freely.

We have seen that inorganic and non-nitrogenous objects placed on the
leaves do not excite any movement; but nitrogenous bodies, if in the
least degree damp, cause after several hours the lobes to close slowly.
Thus bits of quite dry meat and gelatine were placed at opposite ends
of the same leaf, and in the course of 24 hrs. excited neither
secretion nor movement.  They were then dipped in water, their surfaces
dried on blotting paper, and replaced on the same [page 297] leaf, the
plant being now covered with a bell-glass. After 24 hrs. the damp meat
had excited some acid secretion, and the lobes at this end of the leaf
were almost shut. At the other end, where the damp gelatine lay, the
leaf was still quite open, nor had any secretion been excited; so that,
as with Drosera, gelatine is not nearly so exciting a substance as
meat. The secretion beneath the meat was tested by pushing a strip of
litmus paper under it (the filaments not being touched), and this
slight stimulus caused the leaf to shut. On the eleventh day it
reopened; but the end where the gelatine lay, expanded several hours
before the opposite end with the meat.

A second bit of roast meat, which appeared dry, though it had not been
purposely dried, was left for 24 hrs. on a leaf, caused neither
movement nor secretion. The plant in its pot was now covered with a
bell-glass, and the meat absorbed some moisture from the air; this
sufficed to excite acid secretion, and by the next morning the leaf was
closely shut. A third bit of meat, dried so as to be quite brittle, was
placed on a leaf under a bell-glass, and this also became in 24 hrs.
slightly damp, and excited some acid secretion, but no movement.

A rather large piece of perfectly dry albumen was left at one end of a
leaf for 24 hrs. without any effect. It was then soaked for a few
minutes in water, rolled about on blotting paper, and replaced on the
leaf; in 9 hrs. some slightly acid secretion was excited, and in 24
hrs. this end of the leaf was partially closed. The bit of albumen,
which was now surrounded by much secretion, was gently removed, and
although no filament was touched, the lobes closed. In this and the
previous case, it appears that the absorption of animal matter by the
glands renders [page 298] the surface of the leaf much more sensitive
to a touch than it is in its ordinary state; and this is a curious
fact. Two days afterwards the end of the leaf where nothing had been
placed began to open, and on the third day was much more open than the
opposite end where the albumen had lain.

Lastly, large drops of a solution of one part of carbonate of ammonia
to 146 of water were placed on some leaves, but no immediate movement
ensued. I did not then know of the slow movement caused by animal
matter, otherwise I should have observed the leaves for a longer time,
and they would probably have been found closed, though the solution
(judging from Drosera) was, perhaps, too strong.

From the foregoing cases it is certain that bits of meat and albumen,
if at all damp, excite not only the glands to secrete, but the lobes to
close. This movement is widely different from the rapid closure caused
by one of the filaments being touched. We shall see its importance when
we treat of the manner in which insects are captured. There is a great
contrast between Drosera and Dionaea in the effects produced by
mechanical irritation on the one hand, and the absorption of animal
matter on the other. Particles of glass placed on the glands of the
exterior tentacles of Drosera excite movement within nearly the same
time, as do particles of meat, the latter being rather the most
efficient; but when the glands of the disc have bits of meat given
them, they transmit a motor impulse to the exterior tentacles much more
quickly than do these glands when bearing inorganic particles, or when
irritated by repeated touches.  On the other hand, with Dionaea,
touching the filaments excites incomparably quicker movement than the
absorption of animal matter by the glands. Nevertheless, in [page 299]
certain cases, this latter stimulus is the more powerful of the two. On
three occasions leaves were found which from some cause were torpid, so
that their lobes closed only slightly, however much their filaments
were irritated; but on inserting crushed insects between the lobes,
they became in a day closely shut.

The facts just given plainly show that the glands have the power of
absorption, for otherwise it is impossible that the leaves should be so
differently affected by non-nitrogenous and nitrogenous bodies, and
between these latter in a dry and damp condition. It is surprising how
slightly damp a bit of meat or albumen need be in order to excite
secretion and afterwards slow movement, and equally surprising how
minute a quantity of animal matter, when absorbed, suffices to produce
these two effects. It seems hardly credible, and yet it is certainly a
fact, that a bit of hard-boiled white of egg, first thoroughly dried,
then soaked for some minutes in water and rolled on blotting paper,
should yield in a few hours enough animal matter to the glands to cause
them to secrete, and afterwards the lobes to close. That the glands
have the power of absorption is likewise shown by the very different
lengths of time (as we shall presently see) during which the lobes
remain closed over insects and other bodies yielding soluble
nitrogenous matter, and over such as do not yield any. But there is
direct evidence of absorption in the condition of the glands which have
remained for some time in contact with animal matter. Thus bits of meat
and crushed insects were several times placed on glands, and these were
compared after some hours with other glands from distant parts of the
same leaf. The latter showed not a trace of aggregation, whereas those
which had been in contact with the animal matter were [page 300] well
aggregated. Aggregation may be seen to occur very quickly if a piece of
a leaf is immersed in a weak solution of carbonate of ammonia. Again,
small cubes of albumen and gelatine were left for eight days on a leaf,
which was then cut open. The whole surface was bathed with acid
secretion, and every cell in the many glands which were examined had
its contents aggregated in a beautiful manner into dark or pale purple,
or colourless globular masses of protoplasm. These underwent incessant
slow changes of forms; sometimes separating from one another and then
reuniting, exactly as in the cells of Drosera. Boiling water makes the
contents of the gland-cells white and opaque, but not so purely white
and porcelain-like as in the case of Drosera. How living insects, when
naturally caught, excite the glands to secrete so quickly as they do, I
know not; but I suppose that the great pressure to which they are
subjected forces a little excretion from either extremity of their
bodies, and we have seen that an extremely small amount of nitrogenous
matter is sufficient to excite the glands.

Before passing on to the subject of digestion, I may state that I
endeavoured to discover, with no success, the functions of the minute
octofid processes with which the leaves are studded.  From facts
hereafter to be given in the chapters on Aldrovanda and Utricularia, it
seemed probable that they served to absorb decayed matter left by the
captured insects; but their position on the backs of the leaves and on
the footstalks rendered this almost impossible.  Nevertheless, leaves
were immersed in a solution of one part of urea to 437 of water, and
after 24 hrs. the orange layer of protoplasm within the arms of these
processes did not appear more aggregated than in other speci- [page
301] mens kept in water, I then tried suspending a leaf in a bottle
over an excessively putrid infusion of raw meat, to see whether they
absorbed the vapour, but their contents were not affected.

Digestive Power of the Secretion.*--When a leaf closes over any object,
it may be said to form itself into a temporary stomach; and if the
object yields ever so little animal matter, this serves, to use
Schiff's expression, as a peptogene, and the glands on the surface pour
forth their acid secretion, which acts like the gastric juice of
animals. As so many experiments were tried on the digestive power of
Drosera, only a few were made with Dionaea, but they were amply
sufficient to prove that it digests, This plant, moreover, is not so
well fitted as Drosera for observation, as the process goes on within
the closed lobes. Insects, even beetles, after being subjected to the
secretion for several days, are surprisingly softened, though their
chitinous coats are not corroded,

[Experiment 1.--A cube of albumen of 1/10 of an inch (2.540 mm.) was
placed at one end of a leaf, and at the other end an oblong piece of
gelatine, 1/5 of an inch (5.08 mm.) long, and

* Dr. W.M. Canby, of Wilmington, to whom I am much indebted for
information regarding Dionaea in its native home, has published in the
'Gardener's Monthly,' Philadelphia, August 1868, some interesting
observations. He ascertained that the secretion digests animal matter,
such as the contents of insects, bits of meat, &c.; and that the
secretion is reabsorbed. He was also well aware that the lobes remain
closed for a much longer time when in contact with animal matter than
when made to shut by a mere touch, or over objects not yielding soluble
nutriment; and that in these latter cases the glands do not secrete.
The Rev. Dr. Curtis first observed ('Boston Journal Nat. Hist.' vol.
i., p. 123) the secretion from the glands. I may here add that a
gardener, Mr. Knight, is said (Kirby and Spencer's 'Introduction to
Entomology,' 1818, vol. i., p. 295) to have found that a plant of the
Dionaea, on the leaves of which "he laid fine filaments of raw beef,
was much more luxuriant in its growth than others not so treated."
[page 302]

1/10 broad; the leaf was then made to close. It was cut open after 45
hrs. The albumen was hard and compressed, with its angles only a little
rounded; the gelatine was corroded into an oval form; and both were
bathed in so much acid secretion that it dropped off the leaf. The
digestive process apparently is rather slower than in Drosera, and this
agrees with the length of time during which the leaves remain closed
over digestible objects.

Experiment 2.--A bit of albumen 1/10 of an inch square, but only 1/20
in thickness, and a piece of gelatine of the same size as before, were
placed on a leaf, which eight days afterwards was cut open. The surface
was bathed with slightly adhesive, very acid secretion, and the glands
were all in an aggregated condition. Not a vestige of the albumen or
gelatine was left. Similarly sized pieces were placed at the same time
on wet moss on the same pot, so that they were subjected to nearly
similar conditions; after eight days these were brown, decayed, and
matted with fibres of mould, but had not disappeared.

Experiment 3.--A piece of albumen 3/20 of an inch (3.81 mm.) long, and
1/20 broad and thick, and a piece of gelatine of the same size as
before, were placed on another leaf, which was cut open after seven
days; not a vestige of either substance was left, and only a moderate
amount of secretion on the surface.

Experiment 4.--Pieces of albumen and gelatine, of the same size as in
the last experiment, were placed on a leaf, which spontaneously opened
after twelve days, and here again not a vestige of either was left, and
only a little secretion at one end of the midrib.

Experiment 5.--Pieces of albumen and gelatine of the same size were
placed on another leaf, which after twelve days was still firmly
closed, but had begun to wither; it was cut open, and contained nothing
except a vestige of brown matter where the albumen had lain.

Experiment 6.--A cube of albumen of 1/10 of an inch and a piece of
gelatine of the same size as before were placed on a leaf, which opened
spontaneously after thirteen days, The albumen, which was twice as
thick as in the latter experiments, was too large; for the glands in
contact with it were injured and were dropping off; a film also of
albumen of a brown colour, matted with mould, was left. All the
gelatine was absorbed, and there was only a little acid secretion left
on the midrib.

Experiment 7.--A bit of half roasted meat (not measured) and a bit of
gelatine were placed on the two ends of a leaf, which [page 303] opened
spontaneously after eleven days; a vestige of the meat was left, and
the surface of the leaf was here blackened; the gelatine had all
disappeared.

Experiment 8.--A bit of half roasted meat (not measured) was placed on
a leaf which was forcibly kept open by a clip, so that it was moistened
with the secretion (very acid) only on its lower surface. Nevertheless,
after only 22 1/2 hrs. it was surprisingly softened, when compared with
another bit of the same meat which had been kept damp.

Experiment 9.--A cube of 1/10 of an inch of very compact roasted beef
was placed on a leaf, which opened spontaneously after twelve days; so
much feebly acid secretion was left on the leaf that it trickled off.
The meat was completely disintegrated, but not all dissolved; there was
no mould. The little mass was placed under the microscope; some of the
fibrillae in the middle still exhibited transverse striae; others
showed not a vestige of striae; and every gradation could be traced
between these two states. Globules, apparently of fat, and some
undigested fibro-elastic tissue remained. The meat was thus in the same
state as that formerly described, which was half digested by Drosera.
Here, again, as in the case of albumen, the digestive process seems
slower than in Drosera. At the opposite end of the same leaf, a firmly
compressed pellet of bread had been placed; this was completely
disintegrated, I suppose, owing to the digestion of the gluten, but
seemed very little reduced in bulk.

Experiment 10.--A cube of 1/20 of an inch of cheese and another of
albumen were placed at opposite ends of the same leaf. After nine days
the lobes opened spontaneously a little at the end enclosing the
cheese, but hardly any or none was dissolved, though it was softened
and surrounded by secretion. Two days subsequently the end with the
albumen also opened spontaneously (i.e. eleven days after it was put
on), a mere trace in a blackened and dry condition being left.

Experiment 11.--The same experiment with cheese and albumen repeated on
another and rather torpid leaf. The lobes at the end with the cheese,
after an interval of six days, opened spontaneously a little; the cube
of cheese was much softened, but not dissolved, and but little, if at
all, reduced in size. Twelve hours afterwards the end with the albumen
opened, which now consisted of a large drop of transparent, not acid,
viscid fluid.

Experiment 12.--Same experiment as the two last, and here again the
leaf at the end enclosing the cheese opened before the [page 304]
opposite end with the albumen; but no further observations were made.

Experiment 13.--A globule of chemically prepared casein, about 1/10 of
an inch in diameter, was placed on a leaf, which spontaneously opened
after eight days. The casein now consisted of a soft sticky mass, very
little, if at all, reduced in size, but bathed in acid secretion.]

These experiments are sufficient to show that the secretion from the
glands of Dionaea dissolves albumen, gelatine, and meat, if too large
pieces are not given. Globules of fat and fibro-elastic tissue are not
digested. The secretion, with its dissolved matter, if not in excess,
is subsequently absorbed. On the other hand, although chemically
prepared casein and cheese (as in the case of Drosera) excite much acid
secretion, owing, I presume, to the absorption of some included
albuminous matter, these substances are not digested, and are not
appreciably, if at all, reduced in bulk.

[Effects of the Vapours of Chloroform, Sulphuric Ether, and Hydrocyanic
Acid.--A plant bearing one leaf was introduced into a large bottle with
a drachm (3.549 ml.) of chloroform, the mouth being imperfectly closed
with cotton-wool. The vapour caused in 1 m. the lobes to begin moving
at an imperceptibly slow rate; but in 3 m. the spikes crossed, and the
leaf was soon completely shut. The dose, however, was much too large,
for in between 2 and 3 hrs.  the leaf appeared as if burnt, and soon
died.

Two leaves were exposed for 30 m. in a 2-oz: vessel to the vapour of 30
minims (1.774 ml.) of sulphuric ether. One leaf closed after a time, as
did the other whilst being removed from the vessel without being
touched. Both leaves were greatly injured. Another leaf, exposed for 20
m. to 15 minims of ether, closed its lobes to a certain extent, and the
sensitive filaments were now quite insensible. After 24 hrs. this leaf
recovered its sensibility, but was still rather torpid. A leaf exposed
in a large bottle for only 3 m. to ten drops was rendered insensible.
After 52 m. it recovered its sensibility, and when one of the filaments
was touched, the lobes closed. It began [page 305] to reopen after 20
hrs. Lastly another leaf was exposed for 4 m. to only four drops of the
ether; it was rendered insensible, and did not close when its filaments
were repeatedly touched, but closed when the end of the open leaf was
cut off. This shows either that the internal parts had not been
rendered insensible, or that an incision is a more powerful stimulus
than repeated touches on the filaments. Whether the larger doses of
chloroform and ether, which caused the leaves to close slowly, acted on
the sensitive filaments or on the leaf itself, I do not know.

Cyanide of potassium, when left in a bottle, generates prussic or
hydrocyanic acid. A leaf was exposed for 1 hr. 35 m. to the vapour thus
formed; and the glands became within this time so colourless and
shrunken as to be scarcely visible, and I at first thought that they
had all dropped off. The leaf was not rendered insensible; for as soon
as one of the filaments was touched it closed. It had, however,
suffered, for it did not reopen until nearly two days had passed, and
was not even then in the least sensitive. After an additional day it
recovered its powers, and closed on being touched and subsequently
reopened. Another leaf behaved in nearly the same manner after a
shorter exposure to this vapour.]

On the Manner in which Insects are caught.--We will now consider the
action of the leaves when insects happen to touch one of the sensitive
filaments. This often occurred in my greenhouse, but I do not know
whether insects are attracted in any special way by the leaves.  They
are caught in large numbers by the plant in its native country. As soon
as a filament is touched, both lobes close with astonishing quickness;
and as they stand at less than a right angle to each other, they have a
good chance of catching any intruder. The angle between the blade and
footstalk does not change when the lobes close. The chief seat of
movement is near the midrib, but is not confined to this part; for, as
the lobes come together, each curves inwards across its whole breadth;
the marginal spikes however, not becoming curved. This move- [page 306]
ment of the whole lobe was well seen in a leaf to which a large fly had
been given, and from which a large portion had been cut off the end of
one lobe; so that the opposite lobe, meeting with no resistance in this
part, went on curving inwards much beyond the medial line. The whole of
the lobe, from which a portion had been cut, was afterwards removed,
and the opposite lobe now curled completely over, passing through an
angle of from 120o to 130o, so as to occupy a position almost at right
angles to that which it would have held had the opposite lobe been
present.

From the curving inwards of the two lobes, as they move towards each
other, the straight marginal spikes intercross by their tips at first,
and ultimately by their bases. The leaf is then completely shut and
encloses a shallow cavity. If it has been made to shut merely by one of
the sensitive filaments having been touched, or if it includes an
object not yielding soluble nitrogenous matter, the two lobes retain
their inwardly concave form until they re-expand.  The re-expansion
under these circumstances--that is when no organic matter is
enclosed--was observed in ten cases. In all of these, the leaves
re-expanded to about two-thirds of the full extent in 24 hrs. from the
time of closure. Even the leaf from which a portion of one lobe had
been cut off opened to a slight degree within this same time. In one
case a leaf re-expanded to about two-thirds of the full extent in 7
hrs., and completely in 32 hrs.; but one of its filaments had been
touched merely with a hair just enough to cause the leaf to close. Of
these ten leaves only a few re-expanded completely in less than two
days, and two or three required even a little longer time. Before,
however, they fully re-expand, they are ready to close [page 307]
instantly if their sensitive filaments are touched. How many times a
leaf is capable of shutting and opening if no animal matter is left
enclosed, I do not know; but one leaf was made to close four times,
reopening afterwards, within six days, On the last occasion it caught a
fly, and then remained closed for many days.

This power of reopening quickly after the filaments have been
accidentally touched by blades of grass, or by objects blown on the
leaf by the wind, as occasionally happens in its native place,* must be
of some importance to the plant; for as long as a leaf remains closed,
it cannot of course capture an insect.

When the filaments are irritated and a leaf is made to shut over an
insect, a bit of meat, albumen, gelatine, casein, and, no doubt, any
other substance containing soluble nitrogenous matter, the lobes,
instead of remaining concave, thus including a concavity, slowly press
closely together throughout their whole breadth. As this takes place,
the margins gradually become a little everted, so that the spikes,
which at first intercrossed, at last project in two parallel rows. The
lobes press against each other with such force that I have seen a cube
of albumen much flattened, with distinct impressions of the little
prominent glands; but this latter circumstance may have been partly
caused by the corroding action of the secretion. So firmly do they
become pressed together that, if any large insect or other object has
been caught, a corresponding projection on the outside of the leaf is
distinctly visible. When the two lobes are thus completely shut, they

* According to Dr. Curtis, in 'Boston Journal of Nat. Hist,' vol. i
1837, p. 123.  [page 308]

resist being opened, as by a thin wedge driven between them, with
astonishing force, and are generally ruptured rather than yield. If not
ruptured, they close again, as Dr. Canby informs me in a letter, "with
quite a loud flap." But if the end of a leaf is held firmly between the
thumb and finger, or by a clip, so that the lobes cannot begin to
close, they exert, whilst in this position, very little force.

I thought at first that the gradual pressing together of the lobes was
caused exclusively by captured insects crawling over and repeatedly
irritating the sensitive filaments; and this view seemed the more
probable when I learnt from Dr. Burdon Sanderson that whenever the
filaments of a closed leaf are irritated, the normal electric current
is disturbed. Nevertheless, such irritation is by no means necessary,
for a dead insect, or a bit of meat, or of albumen, all act equally
well; proving that in these cases it is the absorption of animal matter
which excites the lobes slowly to press close together. We have seen
that the absorption of an extremely small quantity of such matter also
causes a fully expanded leaf to close slowly; and this movement is
clearly analogous to the slow pressing together of the concave lobes.
This latter action is of high functional importance to the plant, for
the glands on both sides are thus brought into contact with a captured
insect, and consequently secrete. The secretion with animal matter in
solution is then drawn by capillary attraction over the whole surface
of the leaf, causing all the glands to secrete and allowing them to
absorb the diffused animal matter. The movement, excited by the
absorption of such matter, though slow, suffices for its final purpose,
whilst the movement excited by one of the sensitive filaments being
touched is rapid, and this is indis- [page 309] pensable for the
capturing of insects. These two movements, excited by two such widely
different means, are thus both well adapted, like all the other
functions of the plant, for the purposes which they subserve.

There is another wide difference in the action of leaves which enclose
objects, such as bits of wood, cork, balls of paper, or which have had
their filaments merely touched, and those which enclose organic bodies
yielding soluble nitrogenous matter. In the former case the leaves, as
we have seen, open in under 24 hrs. and are then ready, even before
being fully-expanded, to shut again. But if they have closed over
nitrogen-yielding bodies, they remain closely shut for many days; and
after re-expanding are torpid, and never act again, or only after a
considerable interval of time. In four instances, leaves after catching
insects never reopened, but began to wither, remaining closed--in one
case for fifteen days over a fly; in a second, for twenty-four days,
though the fly was small; in a third for twenty-four days over a
woodlouse; and in a fourth, for thirty-five days over a large Tipula.
In two other cases leaves remained closed for at least nine days over
flies, and for how many more I do not know. It should, however, be
added that in two instances in which very small insects had been
naturally caught the leaf opened as quickly as if nothing had been
caught; and I suppose that this was due to such small insects not
having been crushed or not having excreted any animal matter, so that
the glands were not excited. Small angular bits of albumen and gelatine
were placed at both ends of three leaves, two of which remained closed
for thirteen and the other for twelve days. Two other leaves remained
closed over bits of [page 310] meat for eleven days, a third leaf for
eight days, and a fourth (but this had been cracked and injured) for
only six days. Bits of cheese, or casein, were placed at one end and
albumen at the other end of three leaves; and the ends with the former
opened after six, eight, and nine days, whilst the opposite ends opened
a little later. None of the above bits of meat, albumen, &c., exceeded
a cube of 1/10 of an inch (2.54 mm.) in size, and were sometimes
smaller; yet these small portions sufficed to keep the leaves closed
for many days. Dr. Canby informs me that leaves remain shut for a
longer time over insects than over meat; and from what I have seen, I
can well believe that this is the case, especially if the insects are
large.

In all the above cases, and in many others in which leaves remained
closed for a long but unknown period over insects naturally caught,
they were more or less torpid when they reopened. Generally they were
so torpid during many succeeding days that no excitement of the
filaments caused the least movement. In one instance, however, on the
day after a leaf opened which had clasped a fly, it closed with extreme
slowness when one of its filaments was touched; and although no object
was left enclosed, it was so torpid that it did not re-open for the
second time until 44 hrs. had elapsed. In a second case, a leaf which
had expanded after remaining closed for at least nine days over a fly,
when greatly irritated, moved one alone of its two lobes, and retained
this unusual position for the next two days. A third case offers the
strongest exception which I have observed; a leaf, after remaining
clasped for an unknown time over a fly, opened, and when one of its
filaments was touched, closed, though rather slowly. Dr. Canby, [page
311] who observed in the United States a large number of plants which,
although not in their native site, were probably more vigorous than my
plants, informs me that he has "several times known vigorous leaves to
devour their prey several times; but ordinarily twice, or, quite often,
once was enough to render them unserviceable." Mrs. Treat, who
cultivated many plants in New Jersey, also informs me that "several
leaves caught successively three insects each, but most of them were
not able to digest the third fly, but died in the attempt.  Five
leaves, however, digested each three flies, and closed over the fourth,
but died soon after the fourth capture. Many leaves did not digest even
one large insect." It thus appears that the power of digestion is
somewhat limited, and it is certain that leaves always remain clasped
for many days over an insect, and do not recover their power of closing
again for many subsequent days. In this respect Dionaea differs from
Drosera, which catches and digests many insects after shorter intervals
of time.

We are now prepared to understand the use of the marginal spikes, which
form so conspicuous a feature in the appearance of the plant (fig. 12,
p. 287), and which at first seemed to me in my ignorance useless
appendages. From the inward curvature of the lobes as they approach
each other, the tips of the marginal spikes first intercross, and
ultimately their bases. Until the edges of the lobes come into contact,
elongated spaces between the spikes, varying from the 1/15 to the 1/10
of an inch (1.693 to 2.54 mm.) in breadth, according to the size of the
leaf, are left open. Thus an insect, if its body is not thicker than
these measurements, can easily escape between the crossed spikes, when
disturbed by the closing lobes and in- [page 312] creasing darkness;
and one of my sons actually saw a small insect thus escaping. A
moderately large insect, on the other hand, if it tries to escape
between the bars will surely be pushed back again into its horrid
prison with closing walls, for the spikes continue to cross more and
more until the edges of the lobes come into contact. A very strong
insect, however, would be able to free itself, and Mrs. Treat saw this
effected by a rose-chafer (Macrodactylus subspinosus) in the United
States. Now it would manifestly be a great disadvantage to the plant to
waste many days in remaining clasped over a minute insect, and several
additional days or weeks in afterwards recovering its sensibility;
inasmuch as a minute insect would afford but little nutriment. It would
be far better for the plant to wait for a time until a moderately large
insect was captured, and to allow all the little ones to escape; and
this advantage is secured by the slowly intercrossing marginal spikes,
which act like the large meshes of a fishing-net, allowing the small
and useless fry to escape.

As I was anxious to know whether this view was correct--and as it seems
a good illustration of how cautious we ought to be in assuming, as I
had done with respect to the marginal spikes, that any fully developed
structure is useless--I applied to Dr. Canby. He visited the native
site of the plant, early in the season, before the leaves had grown to
their full size, and sent me fourteen leaves, containing naturally
captured insects. Four of these had caught rather small insects, viz.
three of them ants, and the fourth a rather small fly, but the other
ten had all caught large insects, namely, five elaters, two
chrysomelas, a curculio, a thick and broad spider, and a scolopendra.
Out of these ten insects, no less than eight [page 313] were beetles,*
and out of the whole fourteen there was only one, viz. a dipterous
insect, which could readily take flight. Drosera, on the other hand,
lives chiefly on insects which are good flyers, especially Diptera,
caught by the aid of its viscid secretion. But what most concerns us is
the size of the ten larger insects. Their average length from head to
tail was
.256 of an inch, the lobes of the leaves being on an average .53 of an inch in length, so that
the insects were very nearly half as long as the leaves within which
they were enclosed. Only a few of these leaves, therefore, had wasted
their powers by capturing small prey, though it is probable that many
small insects had crawled over them and been caught, but had then
escaped through the bars.

The Transmission of the Motor Impulse, and Means of Movement.--It is
sufficient to touch any one of the six filaments to cause both lobes to
close, these becoming at the same time incurved throughout their whole
breadth. The stimulus must therefore radiate in all directions from any
one filament. It must also be transmitted with much rapidity across the
leaf, for in all ordinary cases both lobes close simultaneously, as far
as the eye can judge. Most physiologists believe that in irritable
plants the excitement is transmitted along, or in close connection
with, the fibro-vascular bundles. In Dionaea, the course of these
vessels (composed of spiral and ordinary vascular

* Dr. Canby remarks ('Gardener's Monthly,' August 1868), "as a general
thing beetles and insects of that kind, though always killed, seem to
be too hard-shelled to serve as food, and after a short time are
rejected." I am surprised at this statement, at least with respect to
such beetles as elaters, for the five which I examined were in an
extremely fragile and empty condition, as if all their internal parts
had been partially digested. Mrs. Treat informs me that the plants
which she cultivated in New Jersey chiefly caught Diptera.  [page 314]

tissue) seems at first sight to favour this belief; for they run up the
midrib in a great bundle, sending off small bundles almost at right
angles on each side. These bifurcate occasionally as they extend
towards the margin, and close to the margin small branches from
adjoining vessels unite and enter the marginal spikes. At some of these
points of union the vessels form curious loops, like those described
under Drosera. A continuous zigzag line of vessels thus runs round the
whole circumference of the leaf, and in the midrib all the vessels are
in close contact; so that all parts of the leaf seem to be brought into
some degree of communication.  Nevertheless, the presence of vessels is
not necessary for the transmission of the motor impulse, for it is
transmitted from the tips of the sensitive filaments (these being about
the 1/20 of an inch in length), into which no vessels enter; and these
could not have been overlooked, as I made thin vertical sections of the
leaf at the bases of the filaments.

On several occasions, slits about the 1/10 of an inch in length were
made with a lancet, close to the bases of the filaments, parallel to
the midrib, and, therefore, directly across the course of the vessels.
These were made sometimes on the inner and sometimes on the outer sides
of the filaments; and after several days, when the leaves had reopened,
these filaments were touched roughly (for they were always rendered in
some degree torpid by the operation), and the lobes then closed in the
ordinary manner, though slowly, and sometimes not until after a
considerable interval of time. These cases show that the motor impulse
is not transmitted along the vessels, and they further show that there
is no necessity for a direct line of communication from the filament
which is [page 315] touched towards the midrib and opposite lobe, or
towards the outer parts of the same lobe.

Two slits near each other, both parallel to the midrib, were next made
in the same manner as before, one on each side of the base of a
filament, on five distinct leaves, so that a little slip bearing a
filament was connected with the rest of the leaf only at its two ends.
These slips were nearly of the same size; one was carefully measured;
it was .12 of an inch (3.048 mm.) in length, and .08 of an inch (2.032
mm.) in breadth; and in the middle stood the filament.  Only one of
these slips withered and perished. After the leaf had recovered from
the operation, though the slits were still open, the filaments thus
circumstanced were roughly touched, and both lobes, or one alone,
slowly closed. In two instances touching the filament produced no
effect; but when the point of a needle was driven into the slip at the
base of the filament, the lobes slowly closed. Now in these cases the
impulse must have proceeded along the slip in a line parallel to the
midrib, and then have radiated forth, either from both ends or from one
end alone of the slip, over the whole surface of the two lobes.

Again, two parallel slits, like the former ones, were made, one on each
side of the base of a filament, at right angles to the midrib. After
the leaves (two in number) had recovered, the filaments were roughly
touched, and the lobes slowly closed; and here the impulse must have
travelled for a short distance in a line at right angles to the midrib,
and then have radiated forth on all sides over both lobes. These
several cases prove that the motor impulse travels in all directions
through the cellular tissue, independently of the course of the
vessels.

With Drosera we have seen that the motor impulse [page 316] is
transmitted in like manner in all directions through the cellular
tissue; but that its rate is largely governed by the length of the
cells and the direction of their longer axes. Thin sections of a leaf
of Dionaea were made by my son, and the cells, both those of the
central and of the more superficial layers, were found much elongated,
with their longer axes directed towards the midrib; and it is in this
direction that the motor impulse must be sent with great rapidity from
one lobe to the other, as both close simultaneously. The central
parenchymatous cells are larger, more loosely attached together, and
have more delicate walls than the more superficial cells. A thick mass
of cellular tissue forms the upper surface of the midrib over the great
central bundle of vessels.

When the filaments were roughly touched, at the bases of which slits
had been made, either on both sides or on one side, parallel to the
midrib or at right angles to it, the two lobes, or only one, moved. In
one of these cases, the lobe on the side which bore the filament that
was touched moved, but in three other cases the opposite lobe alone
moved; so that an injury which was sufficient to prevent a lobe moving
did not prevent the transmission from it of a stimulus which excited
the opposite lobe to move. We thus also learn that, although normally
both lobes move together, each has the power of independent movement. A
case, indeed, has already been given of a torpid leaf that had lately
re-opened after catching an insect, of which one lobe alone moved when
irritated. Moreover, one end of the same lobe can close and re- expand,
independently of the other end, as was seen in some of the foregoing
experiments.

When the lobes, which are rather thick, close, no trace of wrinkling
can be seen on any part of their upper [page 317] surfaces, It appears
therefore that the cells must contract. The chief seat of the movement
is evidently in the thick mass of cells which overlies the central
bundle of vessels in the midrib.  To ascertain whether this part
contracts, a leaf was fastened on the stage of the microscope in such a
manner that the two lobes could not become quite shut, and having made
two minute black dots on the midrib, in a transverse line and a little
towards one side, they were found by the micrometer to be 17/1000 of an
inch apart. One of the filaments was then touched and the lobes closed;
but as they were prevented from meeting, I could still see the two
dots, which now were 15/1000 of an inch apart, so that a small portion
of the upper surface of the midrib had contracted in a transverse line
2/1000 of an inch (.0508 mm.).

We know that the lobes, whilst closing, become slightly incurved
throughout their whole breadth. This movement appears to be due to the
contraction of the superficial layers of cells over the whole upper
surface. In order to observe their contraction, a narrow strip was cut
out of one lobe at right angles to the midrib, so that the surface of
the opposite lobe could be seen in this part when the leaf was shut.
After the leaf had recovered from the operation and had re-expanded,
three minute black dots were made on the surface opposite to the slit
or window, in a line at right angles to the midrib. The distance
between the dots was found to be 40/1000 of an inch, so that the two
extreme dots were 80/1000 of an inch apart. One of the filaments was
now touched and the leaf closed. On again measuring the distances
between the dots, the two next to the midrib were nearer together by 1
to 2/1000 of an inch, and the two further dots by 3 to 4/1000 of an
inch, than they were before; so that the two extreme [page 318] dots
now stood about 5/1000 of an inch (.127 mm.) nearer together than
before. If we suppose the whole upper surface of the lobe, which was
400/1000 of an inch in breadth, to have contracted in the same
proportion, the total contraction will have amounted to about 25/1000
or 1/40 of an inch (.635 mm.); but whether this is sufficient to
account for the slight inward curvature of the whole lobe, I am unable
to say.

Finally, with respect to the movement of the leaves, the wonderful
discovery made by Dr.  Burdon Sanderson* is now universally known;
namely that there exists a normal electrical current in the blade and
footstalk; and that when the leaves are irritated, the current is
disturbed in the same manner as takes place during the contraction of
the muscle of an animal.

The Re-expansion of the Leaves.--This is effected at an insensibly slow
rate, whether or not any object is enclosed.  One lobe can re-expand by
itself, as occurred with the torpid leaf of which one lobe alone had
closed. We have also seen in the experiments with cheese and albumen
that the two ends of the same lobe can re-expand to a certain extent
independently of each other. But in all ordinary cases both lobes open
at the same time. The re-expansion is not determined by the sensitive
filaments; all three filaments on one lobe were cut off close to their
bases; and the three

* Proc. Royal Soc.' vol. xxi. p. 495; and lecture at the Royal
Institution, June 5, 1874, given in 'Nature,' 1874, pp. 105 and 127.

  Nuttall, in his 'Gen. American Plants,' p. 277 (note), says that,
  whilst collecting this plant in its native home, "I had occasion to
observe that a detached leaf would make repeated efforts towards
disclosing itself to the influence of the sun; these attempts consisted
in an undulatory motion of the marginal ciliae, accompanied by a
partial opening and succeeding collapse of the lamina, which at length
terminated in a complete expansion and in the destruction of
sensibility." I am indebted to Prof. Oliver for this reference; but I
do not understand what took place.  [page 319]

leaves thus treated re-expanded,--one to a partial extent in 24
hrs.,--a second to the same extent in 48 hrs., and the third, which had
been previously injured, not until the sixth day.  These leaves after
their re-expansion closed quickly when the filaments on the other lobe
were irritated. These were then cut off one of the leaves, so that none
were left. This mutilated leaf, notwithstanding the loss of all its
filaments, re-expanded in two days in the usual manner. When the
filaments have been excited by immersion in a solution of sugar, the
lobes do not expand so soon as when the filaments have been merely
touched; and this, I presume, is due to their having been strongly
affected through exosmose, so that they continue for some time to
transmit a motor impulse to the upper surface of the leaf.

The following facts make me believe that the several layers of cells
forming the lower surface of the leaf are always in a state of tension;
and that it is owing to this mechanical state, aided probably by fresh
fluid being attracted into the cells, that the lobes begin to separate
or expand as soon as the contraction of the upper surface diminishes. A
leaf was cut off and suddenly plunged perpendicularly into boiling
water: I expected that the lobes would have closed, but instead of
doing so, they diverged a little. I then took another fine leaf, with
the lobes standing at an angle of nearly 80o to each other; and on
immersing it as before, the angle suddenly increased to 90o. A third
leaf was torpid from having recently re-expanded after having caught a
fly, so that repeated touches of the filaments caused not the least
movement; nevertheless, when similarly immersed, the lobes separated a
little. As these leaves were inserted perpendicularly into the boiling
water, both surfaces and the filaments [page 320] must have been
equally affected; and I can understand the divergence of the lobes only
by supposing that the cells on the lower side, owing to their state of
tension, acted mechanically and thus suddenly drew the lobes a little
apart, as soon as the cells on the upper surface were killed and lost
their contractile power. We have seen that boiling water in like manner
causes the tentacles of Drosera to curve backwards; and this is an
analogous movement to the divergence of the lobes of Dionaea.

In some concluding remarks in the fifteenth chapter on the Droseraceae,
the different kinds of irritability possessed by the several genera,
and the different manner in which they capture insects, will be
compared.  [page 321]



                          CHAPTER XIV.

                     ALDROVANDA VESICULOSA.

Captures crustaceans--Structure of the leaves in comparison with those
of Dionaea-- Absorption by the glands, by the quadrifid processes, and
points on the infolded margins-- Aldrovanda vesiculosa, var.
australis--Captures prey--Absorption of animal matter-- Aldrovanda
vesiculosa, var. verticillata--Concluding remarks.

THIS plant may be called a miniature aquatic Dionaea. Stein discovered
in 1873 that the bilobed leaves, which are generally found closed in
Europe, open under a sufficiently high temperature, and, when touched,
suddenly close.* They re-expand in from 24 to 36 hours, but only, as it
appears, when inorganic objects are enclosed. The leaves sometimes
contain bubbles of air, and were formerly supposed to be bladders;
hence the specific name of vesiculosa. Stein observed that
water-insects were sometimes caught, and Prof. Cohn has recently found
within the leaves of naturally growing plants many kinds of crustaceans
and larvae.  Plants which had been kept in filtered water were placed
by him in a vessel con-

* Since his original publication, Stein has found out that the
irritability of the leaves was observed by De Sassus, as recorded in
'Bull. Bot. Soc. de France,' in 1861. Delpino states in a paper
published in 1871 ('Nuovo Giornale Bot. Ital.' vol. iii. p. 174) that
"una quantit di chioccioline e di altri animalcoli acquatici" are
caught and suffocated by the leaves. I presume that chioccioline are
fresh-water molluscs. It would be interesting to know whether their
shells are at all corroded by the acid of the digestive secretion.

  I am greatly indebted to this distinguished naturalist for having
  sent me a copy of his memoir on Aldrovanda, before its publication in
his 'Beitrge zur Biologie der Pflanzen,' drittes Heft, 1875, page 71.
[page 322]

taining numerous crustaceans of the genus Cypris, and next morning many
were found imprisoned and alive, still swimming about within the closed
leaves, but doomed to certain death.

Directly after reading Prof. Cohn's memoir, I received through the
kindness of Dr. Hooker living plants from Germany. As I can add nothing
to Prof. Cohn's excellent description, I will give only two
illustrations, one of a whorl of leaves copied from his work, and the
other of a leaf pressed flat open, drawn by my son Francis. I will,
however, append a few remarks on the differences between this plant and
Dionaea.

Aldrovanda is destitute of roots and floats freely in the water. The
leaves are arranged in whorls round the stem. Their broad petioles
terminate in from four to six rigid projections,* each tipped with a
stiff, short bristle. The bilobed leaf, with the midrib likewise tipped
with a bristle, stands in the midst of these projections, and is
evidently defended by them. The lobes are formed of very delicate
tissue, so as to be translucent; they open, according to Cohn, about as
much as the two valves of a living mussel-shell, therefore even less
than the lobes of Dionaea; and this must make the capture of aquatic
animals more easy. The outside of the leaves and the petioles are
covered with minute two-armed papillae, evidently answering to the
eight-rayed papillae of Dionaea.

Each lobe rather exceeds a semi-circle in convexity, and consists of
two very different concentric portions; the inner and lesser portion,
or that next to the midrib,

*There has been much discussion by botanists on the homological nature
of these projections. Dr. Nitschke ('Bot. Zeitung,' 1861, p. 146)
believes that they correspond with the fimbriated scale-like bodies
found at the bases of the petioles of Drosera.  [page 323]

is slightly concave, and is formed, according to Cohn, of three layers
of cells. Its upper surface is studded with colourless glands like, but
more simple than, those of Dionaea; they are supported on distinct
footstalks, consisting of two rows of cells. The outer

FIG. 13.  (Aldrovanda vesiculosa.) Upper figure, whorl of leaves (from
Prof. Cohn).  Lower figure, leaf pressed flat open and greatly
enlarged.

and broader portion of the lobe is flat and very thin, being formed of
only two layers of cells.  Its upper surface does not bear any glands,
but, in their place, small quadrifid processes, each consisting of four
tapering projections, which rise from a common [page 324] prominence.
These processes are formed of very delicate membrane lined with a layer
of protoplasm; and they sometimes contain aggregated globules of
hyaline matter. Two of the slightly diverging arms are directed towards
the circumference, and two towards the midrib, forming together a sort
of Greek cross. Occasionally two of the arms are replaced by one, and
then the projection is trifid. We shall see in a future chapter that
these projections curiously resemble those found within the bladders of
Utricularia, more especially of Utricularia montana, although this
genus is not related to Aldrovanda.

A narrow rim of the broad flat exterior part of each lobe is turned
inwards, so that, when the lobes are closed, the exterior surfaces of
the infolded portions come into contact. The edge itself bears a row of
conical, flattened, transparent points with broad bases, like the
prickles on the stem of a bramble or Rubus. As the rim is infolded,
these points are directed towards the midrib, and they appear at first
as if they were adapted to prevent the escape of prey; but this can
hardly be their chief function, for they are composed of very delicate
and highly flexible membrane, which can be easily bent or quite doubled
back without being cracked.  Nevertheless, the infolded rims, together
with the points, must somewhat interfere with the retrograde movement
of any small creature, as soon as the lobes begin to close. The
circumferential part of the leaf of Aldrovanda thus differs greatly
from that of Dionaea; nor can the points on the rim be considered as
homologous with the spikes round the leaves of Dionaea, as these latter
are prolongations of the blade, and not mere epidermic productions.
They appear also to serve for a widely different purpose.  [page 325]

On the concave gland-bearing portion of the lobes, and especially on
the midrib, there are numerous, long, finely pointed hairs, which, as
Prof. Cohn remarks, there can be little doubt are sensitive to a touch,
and, when touched, cause the leaf to close. They are formed of two rows
of cells, or, according to Cohn, sometimes of four, and do not include
any vascular tissue. They differ also from the six sensitive filaments
of Dionaea in being colourless, and in having a medial as well as a
basal articulation. No doubt it is owing to these two articulations
that, notwithstanding their length, they escape being broken when the
lobes close.

The plants which I received during the early part of October from Kew
never opened their leaves, though subjected to a high temperature.
After examining the structure of some of them, I experimented on only
two, as I hoped that the plants would grow; and I now regret that I did
not sacrifice a greater number.

A leaf was cut open along the midrib, and the glands examined under a
high power. It was then placed in a few drops of an infusion of raw
meat. After 3 hrs. 20 m. there was no change, but when next examined
after 23 hrs. 20 m., the outer cells of the glands contained, instead
of limpid fluid, spherical masses of a granular substance, showing that
matter had been absorbed from the infusion. That these glands secrete a
fluid which dissolves or digests animal matter out of the bodies of the
creatures which the leaves capture, is also highly probable from the
analogy of Dionaea. If we may trust to the same analogy, the concave
and inner portions of the two lobes probably close together by a slow
movement, as soon as the glands have absorbed a slight amount of [page
326] already soluble animal matter. The included water would thus be
pressed out, and the secretion consequently not be too much diluted to
act. With respect to the quadrifid processes on the outer parts of the
lobes, I was not able to decide whether they had been acted on by the
infusion; for the lining of protoplasm was somewhat shrunk before they
were immersed.  Many of the points on the infolded rims also had their
lining of protoplasm similarly shrunk, and contained spherical granules
of hyaline matter.

A solution of urea was next employed. This substance was chosen partly
because it is absorbed by the quadrifid processes and more especially
by the glands of Utricularia--a plant which, as we shall hereafter see,
feeds on decayed animal matter. As urea is one of the last products of
the chemical changes going on in the living body, it seems fitted to
represent the early stages of the decay of the dead body. I was also
led to try urea from a curious little fact mentioned by Prof. Cohn,
namely that when rather large crustaceans are caught between the
closing lobes, they are pressed so hard whilst making their escape that
they often void their sausage-shaped masses of excrement, which were
found within most of the leaves. These masses, no doubt, contain urea.
They would be left either on the broad outer surfaces of the lobes
where the quadrifids are situated, or within the closed concavity. In
the latter case, water charged with excrementitious and decaying matter
would be slowly forced outwards, and would bathe the quadrifids, if I
am right in believing that the concave lobes contract after a time like
those of Dionaea. Foul water would also be apt to ooze out at all
times, especially when bubbles of air were generated within the
concavity.

A leaf was cut open and examined, and the outer [page 327] cells of the
glands were found to contain only limpid fluid. Some of the quadrifids
included a few spherical granules, but several were transparent and
empty, and their positions were marked. This leaf was now immersed in a
little solution of one part of urea to 146 of water, or three grains to
the ounce. After 3 hrs. 40 m. there was no change either in the glands
or quadrifids; nor was there any certain change in the glands after 24
hrs.; so that, as far as one trial goes, urea does not act on them in
the same manner as an infusion of raw meat. It was different with the
quadrifids; for the lining of protoplasm, instead of presenting a
uniform texture, was now slightly shrunk, and exhibited in many places
minute, thickened, irregular, yellowish specks and ridges, exactly like
those which appear within the quadrifids of Utricularia when treated
with this same solution. Moreover, several of the quadrifids, which
were before empty, now contained moderately sized or very small, more
or less aggregated, globules of yellowish matter, as likewise occurs
under the same circumstances with Utricularia. Some of the points on
the infolded margins of the lobes were similarly affected; for their
lining of protoplasm was a little shrunk and included yellowish specks;
and those which were before empty now contained small spheres and
irregular masses of hyaline matter, more or less aggregated; so that
both the points on the margins and the quadrifids had absorbed matter
from the solution in the course of 24 hrs.; but to this subject I shall
recur. In another rather old leaf, to which nothing had been given, but
which had been kept in foul water, some of the quadrifids contained
aggregated translucent globules. These were not acted on by a solution
of one part of carbonate of ammonia to 218 of water; and this negative
result [page 328] agrees with what I have observed under similar
circumstances with Utricularia.

Aldrovanda vesiculosa, var. australis.--Dried leaves of this plant from
Queensland in Australia were sent me by Prof. Oliver from the herbarium
at Kew. Whether it ought to be considered as a distinct species or a
variety, cannot be told until the flowers are examined by a botanist.
The projections at the upper end of the petiole (from four to six in
number) are considerably longer relatively to the blade, and much more
attenuated than those of the European form. They are thickly covered
for a considerable space near their extremities with the upcurved
prickles, which are quite absent in the latter form; and they generally
bear on their tips two or three straight prickles instead of one. The
bilobed leaf appears also to be rather larger and somewhat broader,
with the pedicel by which it is attached to the upper end of the
petiole a little longer. The points on the infolded margins likewise
differ; they have narrower bases, and are more pointed; long and short
points also alternate with much more regularity than in the European
form. The glands and sensitive hairs are similar in the two forms. No
quadrifid processes could be seen on several of the leaves, but I do
not doubt that they were present, though indistinguishable from their
delicacy and from having shrivelled; for they were quite distinct on
one leaf under circumstances presently to be mentioned.

Some of the closed leaves contained no prey, but in one there was a
rather large beetle, which from its flattened tibiae I suppose was an
aquatic species, but was not allied to Colymbetes. All the softer
tissues of this beetle were completely dissolved, and its chitinous
integuments were as clean as if they had been [page 329] boiled in
caustic potash; so that it must have been enclosed for a considerable
time. The glands were browner and more opaque than those on other
leaves which had caught nothing; and the quadrifid processes, from
being partly filled with brown granular matter, could be plainly
distinguished, which was not the case, as already stated, on the other
leaves. Some of the points on the infolded margins likewise contained
brownish granular matter. We thus gain additional evidence that the
glands, the quadrifid processes, and the marginal points, all have the
power of absorbing matter, though probably of a different nature.

Within another leaf disintegrated remnants of a rather small animal,
not a crustacean, which had simple, strong, opaque mandibles, and a
large unarticulated chitinous coat, were present.  Lumps of black
organic matter, possibly of a vegetable nature, were enclosed in two
other leaves; but in one of these there was also a small worm much
decayed. But the nature of partially digested and decayed bodies, which
have been pressed flat, long dried, and then soaked in water, cannot be
recognised easily. All the leaves contained unicellular and other
Algae, still of a greenish colour, which had evidently lived as
intruders, in the same manner as occurs, according to Cohn, within the
leaves of this plant in Germany.

Aldrovanda vesiculosa, var. verticillata.--Dr. King, Superintendent of
the Botanic Gardens, kindly sent me dried specimens collected near
Calcutta. This form was, I believe, considered by Wallich as a distinct
species, under the name of verticillata. It resembles the Australian
form much more nearly than the European; namely in the projections at
the upper end of the petiole being much attenuated and covered with
[page 330] upcurved prickles; they terminate also in two straight
little prickles. The bilobed leaves are, I believe, larger and
certainly broader even than those of the Australian form; so that the
greater convexity of their margins was conspicuous. The length of an
open leaf being taken at 100, the breadth of the Bengal form is nearly
173, of the Australian form 147, and of the German 134. The points on
the infolded margins are like those in the Australian form. Of the few
leaves which were examined, three contained entomostracan crustaceans.

Concluding Remarks.--The leaves of the three foregoing closely allied
species or varieties are manifestly adapted for catching living
creatures. With respect to the functions of the several parts, there
can be little doubt that the long jointed hairs are sensitive, like
those of Dionaea, and that, when touched, they cause the lobes to
close. That the glands secrete a true digestive fluid and afterwards
absorb the digested matter, is highly probable from the analogy of
Dionaea,--from the limpid fluid within their cells being aggregated
into spherical masses, after they had absorbed an infusion of raw
meat,--from their opaque and granular condition in the leaf, which had
enclosed a beetle for a long time,--and from the clean condition of the
integuments of this insect, as well as of crustaceans (as described by
Cohn), which have been long captured. Again, from the effect produced
on the quadrifid processes by an immersion for 24 hrs. in a solution of
urea,--from the presence of brown granular matter within the quadrifids
of the leaf in which the beetle had been caught,--and from the analogy
of Utricularia,--it is probable that these processes absorb
excrementitious and decaying animal matter. It is a more curious fact
that the points on [page 331] the infolded margins apparently serve to
absorb decayed animal matter in the same manner as the quadrifids. We
can thus understand the meaning of the infolded margins of the lobes
furnished with delicate points directed inwards, and of the broad,
flat, outer portions, bearing quadrifid processes; for these surfaces
must be liable to be irrigated by foul water flowing from the concavity
of the leaf when it contains dead animals. This would follow from
various causes,--from the gradual contraction of the concavity,--from
fluid in excess being secreted,- -and from the generation of bubbles of
air. More observations are requisite on this head; but if this view is
correct, we have the remarkable case of different parts of the same
leaf serving for very different purposes--one part for true digestion,
and another for the absorption of decayed animal matter. We can thus
also understand how, by the gradual loss of either power, a plant might
be gradually adapted for the one function to the exclusion of the
other; and it will hereafter be shown that two genera, namely
Pinguicula and Utricularia, belonging to the same family, have been
adapted for these two different functions.  [page 332]




                          CHAPTER XV.

DROSOPHYLLUM--RORIDULA--BYBLIS--GLANDULAR HAIRS OF OTHER PLANTS--
            CONCLUDING REMARKS ON THE DROSERACEAE.

Drosophyllum--Structure of leaves--Nature of the secretion--Manner of
catching insects-- Power of absorption--Digestion of animal
substances--Summary on Drosophyllum--Roridula- -Byblis--Glandular hairs
of other plants, their power of absorption--Saxifraga--Primula--
Pelargonium--Erica--Mirabilis--Nicotiana--Summary on glandular
hairs--Concluding remarks on the Droseraceae.

DROSOPHYLLUM LUSITANICUM.--This rare plant has been found only in
Portugal, and, as I hear from Dr. Hooker, in Morocco. I obtained living
specimens through the great kindness of Mr. W.C. Tait, and afterwards
from Mr. G. Maw and Dr. Moore. Mr. Tait informs me that it grows
plentifully on the sides of dry hills near Oporto, and that vast
numbers of flies adhere to the leaves. This latter fact is well-known
to the villagers, who call the plant the "fly-catcher, " and hang it up
in their cottages for this purpose. A plant in my hot-house caught so
many insects during the early part of April, although the weather was
cold and insects scarce, that it must have been in some manner strongly
attractive to them.  On four leaves of a young and small plant, 8, 10,
14, and 16 minute insects, chiefly Diptera, were found in the autumn
adhering to them. I neglected to examine the roots, but I hear from Dr.
Hooker that they are very small, as in the case of the previously
mentioned members of the same family of the Droseraceae.

The leaves arise from an almost woody axis; they [page 333] are linear,
much attenuated towards their tips, and several inches in length. The
upper surface is concave, the lower convex, with a narrow channel down
the middle. Both surfaces, with the exception of the channel, are
covered with glands, supported on pedicels and arranged in irregular
longitudinal rows. These organs I shall call tentacles, from their
close resemblance to those of Drosera, though they have no power of
movement. Those on the same leaf differ much in length. The glands also
differ in size, and are of a bright pink or of a purple colour; their
upper surfaces are convex, and the lower flat or even concave, so that
they resemble miniature mushrooms in appearance. They are formed of two
(as I believe) layers of delicate angular cells, enclosing eight or ten
larger cells with thicker, zigzag walls. Within these larger cells
there are others marked by spiral lines, and apparently connected with
the spiral vessels which run up the green multi-cellular pedicels. The
glands secrete large drops of viscid secretion. Other glands, having
the same general appearance, are found on the flower-peduncles and
calyx.

FIG. 14.  (Drosophyllum lusitanicum.) Part of leaf, enlarged seven
times, showing lower surface.

Besides the glands which are borne on longer or shorter pedicels, there
are numerous ones, both on the upper and lower surfaces of the leaves,
so small as to be scarcely visible to the naked eye. They are
colourless and almost sessile, either circular or oval in outline; the
latter occurring chiefly on the backs of the leaves (fig. 14).
Internally they have exactly the same structure as the larger glands
which are supported on pedicels; [page 334] and indeed the two sets
almost graduate into one another. But the sessile glands differ in one
important respect, for they never secrete spontaneously, as far as I
have seen, though I have examined them under a high power on a hot day,
whilst the glands on pedicels were secreting copiously. Nevertheless,
if little bits of damp albumen or fibrin are placed on these sessile
glands, they begin after a time to secrete, in the same manner as do
the glands of Dionaea when similarly treated. When they were merely
rubbed with a bit of raw meat, I believe that they likewise secreted.
Both the sessile glands and the taller ones on pedicels have the power
of rapidly absorbing nitrogenous matter.

The secretion from the taller glands differs in a remarkable manner
from that of Drosera, in being acid before the glands have been in any
way excited; and judging from the changed colour of litmus paper, more
strongly acid than that of Drosera. This fact was observed repeatedly;
on one occasion I chose a young leaf, which was not secreting freely,
and had never caught an insect, yet the secretion on all the glands
coloured litmus paper of a bright red. From the quickness with which
the glands are able to obtain animal matter from such substances as
well-washed fibrin and cartilage, I suspect that a small quantity of
the proper ferment must be present in the secretion before the glands
are excited, so that a little animal matter is quickly dissolved.

Owing to the nature of the secretion or to the shape of the glands, the
drops are removed from them with singular facility. It is even somewhat
difficult, by the aid of a finely pointed polished needle, slightly
damped with water, to place a minute particle of any kind on one of the
drops; for on withdrawing the [page 335] needle, the drop is generally
withdrawn; whereas with Drosera there is no such difficulty, though the
drops are occasionally withdrawn. From this peculiarity, when a small
insect alights on a leaf of Drosophyllum, the drops adhere to its
wings, feet, or body, and are drawn from the gland; the insect then
crawls onward and other drops adhere to it; so that at last, bathed by
the viscid secretion, it sinks down and dies, resting on the small
sessile glands with which the surface of the leaf is thickly covered.
In the case of Drosera, an insect sticking to one or more of the
exterior glands is carried by their movement to the centre of the leaf;
with Drosophyllum, this is effected by the crawling of the insect, as
from its wings being clogged by the secretion it cannot fly away.

There is another difference in function between the glands of these two
plants: we know that the glands of Drosera secrete more copiously when
properly excited. But when minute particles of carbonate of ammonia,
drops of a solution of this salt or of the nitrate of ammonia, saliva,
small insects, bits of raw or roast meat, albumen, fibrin or cartilage,
as well as inorganic particles, were placed on the glands of
Drosophyllum, the amount of secretion never appeared to be in the least
increased. As insects do not commonly adhere to the taller glands, but
withdraw the secretion, we can see that there would be little use in
their having acquired the habit of secreting copiously when stimulated;
whereas with Drosera this is of use, and the habit has been acquired.
Nevertheless, the glands of Drosophyllum, without being stimulated,
continually secrete, so as to replace the loss by evaporation. Thus
when a plant was placed under a small bell-glass with its inner surface
and support thoroughly wetted, there was no loss by evaporation, and so
much [page 336] secretion was accumulated in the course of a day that
it ran down the tentacles and covered large spaces of the leaves.

The glands to which the above named nitrogenous substances and liquids
were given did not, as just stated, secrete more copiously; on the
contrary, they absorbed their own drops of secretion with surprising
quickness. Bits of damp fibrin were placed on five glands, and when
they were looked at after an interval of 1 hr. 12 m., the fibrin was
almost dry, the secretion having been all absorbed. So it was with
three cubes of albumen after 1 hr. 19 m., and with four other cubes,
though these latter were not looked at until 2 hrs. 15 m. had elapsed.
The same result followed in between 1 hr. 15 m. and 1 hr. 30 m. when
particles both of cartilage and meat were placed on several glands.
Lastly, a minute drop (about 1/20 of a minim) of a solution of one part
of nitrate of ammonia to 146 of water was distributed between the
secretion surrounding three glands, so that the amount of fluid
surrounding each was slightly increased; yet when looked at after 2
hrs., all three were dry. On the other hand, seven particles of glass
and three of coal-cinders, of nearly the same size as those of the
above named organic substances, were placed on ten glands; some of them
being observed for 18 hrs., and others for two or three days; but there
was not the least sign of the secretion being absorbed. Hence, in the
former cases, the absorption of the secretion must have been due to the
presence of some nitrogenous matter, which was either already soluble
or was rendered so by the secretion. As the fibrin was pure, and had
been well washed in distilled water after being kept in glycerine, and
as the cartilage had been soaked in water, I suspect that these
substances must [page 337] have been slightly acted on and rendered
soluble within the above stated short periods.

The glands have not only the power of rapid absorption, but likewise of
secreting again quickly; and this latter habit has perhaps been gained,
inasmuch as insects, if they touch the glands, generally withdraw the
drops of secretion, which have to be restored. The exact period of
re-secretion was recorded in only a few cases. The glands on which bits
of meat were placed, and which were nearly dry after about 1 hr. 30 m.,
when looked at after 22 additional hours, were found secreting; so it
was after 24 hrs. with one gland on which a bit of albumen had been
placed. The three glands to which a minute drop of a solution of
nitrate of ammonia was distributed, and which became dry after 2 hrs.,
were beginning to re-secrete after only 12 additional hours.

Tentacles Incapable of Movement.--Many of the tall tentacles, with
insects adhering to them, were carefully observed; and fragments of
insects, bits of raw meat, albumen, &c., drops of a solution of two
salts of ammonia and of saliva, were placed on the glands of many
tentacles; but not a trace of movement could ever be detected. I also
repeatedly irritated the glands with a needle, and scratched and
pricked the blades, but neither the blade nor the tentacles became at
all inflected. We may therefore conclude that they are incapable of
movement.

On the Power of Absorption possessed by the Glands.--It has already
been indirectly shown that the glands on pedicels absorb animal matter;
and this is further shown by their changed colour, and by the
aggregation of their contents, after they have been left in contact
with nitrogenous substances or liquids. The following observations
apply both to the glands supported on [page 338] pedicels and to the
minute sessile ones. Before a gland has been in any way stimulated, the
exterior cells commonly contain only limpid purple fluid; the more
central ones including mulberry-like masses of purple granular matter.
A leaf was placed in a little solution of one part of carbonate of
ammonia to 146 of water (3 grs. to 1 oz.), and the glands were
instantly darkened and very soon became black; this change being due to
the strongly marked aggregation of their contents, more especially of
the inner cells. Another leaf was placed in a solution of the same
strength of nitrate of ammonia, and the glands were slightly darkened
in 25 m., more so in 50 m., and after 1 hr. 30 m. were of so dark a red
as to appear almost black.  Other leaves were placed in a weak infusion
of raw meat and in human saliva, and the glands were much darkened in
25 m., and after 40 m. were so dark as almost to deserve to be called
black. Even immersion for a whole day in distilled water occasionally
induces some aggregation within the glands, so that they become of a
darker tint. In all these cases the glands are affected in exactly the
same manner as those of Drosera. Milk, however, which acts so
energetically on Drosera, seems rather less effective on Drosophyllum,
for the glands were only slightly darkened by an immersion of 1 hr. 20
m., but became decidedly darker after 3 hrs. Leaves which had been left
for 7 hrs. in an infusion of raw meat or in saliva were placed in the
solution of carbonate of ammonia, and the glands now became greenish;
whereas, if they had been first placed in the carbonate, they would
have become black. In this latter case, the ammonia probably combines
with the acid of the secretion, and therefore does not act on the
colouring matter; but when the glands are first subjected to an organic
[page 339] fluid, either the acid is consumed in the work of digestion
or the cell-walls are rendered more permeable, so that the undecomposed
carbonate enters and acts on the colouring matter. If a particle of the
dry carbonate is placed on a gland, the purple colour is quickly
discharged, owing probably to an excess of the salt. The gland,
moreover, is killed.

Turning now to the action of organic substances, the glands on which
bits of raw meat were placed became dark-coloured; and in 18 hrs. their
contents were conspicuously aggregated.  Several glands with bits of
albumen and fibrin were darkened in between 2 hrs. and 3 hrs.; but in
one case the purple colour was completely discharged. Some glands which
had caught flies were compared with others close by; and though they
did not differ much in colour, there was a marked difference in their
state of aggregation. In some few instances, however, there was no such
difference, and this appeared to be due to the insects having been
caught long ago, so that the glands had recovered their pristine state.
In one case, a group of the sessile colourless glands, to which a small
fly adhered, presented a peculiar appearance; for they had become
purple, owing to purple granular matter coating the cell-walls. I may
here mention as a caution that, soon after some of my plants arrived in
the spring from Portugal, the glands were not plainly acted on by bits
of meat, or insects, or a solution of ammonia--a circumstance for which
I cannot account.

Digestion of Solid Animal Matter.--Whilst I was trying to place on two
of the taller glands little cubes of albumen, these slipped down, and,
besmeared with secretion, were left resting on some of the small
sessile glands. After 24 hrs. one of these cubes was found [page 340]
completely liquefied, but with a few white streaks still visible; the
other was much rounded, but not quite dissolved. Two other cubes were
left on tall glands for 2 hrs. 45 m., by which time all the secretion
was absorbed; but they were not perceptibly acted on, though no doubt
some slight amount of animal matter had been absorbed from them. They
were then placed on the small sessile glands, which being thus
stimulated secreted copiously in the course of 7 hrs. One of these
cubes was much liquefied within this short time; and both were
completely liquefied after 21 hrs. 15 m.; the little liquid masses,
however, still showing some white streaks. These streaks disappeared
after an additional period of 6 hrs. 30 m.; and by next morning (i.e.
48 hrs. from the time when the cubes were first placed on the glands)
the liquefied matter was wholly absorbed. A cube of albumen was left on
another tall gland, which first absorbed the secretion and after 24
hrs. poured forth a fresh supply. This cube, now surrounded by
secretion, was left on the gland for an additional 24 hrs., but was
very little, if at all, acted on. We may, therefore, conclude, either
that the secretion from the tall glands has little power of digestion,
though strongly acid, or that the amount poured forth from a single
gland is insufficient to dissolve a particle of albumen which within
the same time would have been dissolved by the secretion from several
of the small sessile glands.  Owing to the death of my last plant, I
was unable to ascertain which of these alternatives is the true one.

Four minute shreds of pure fibrin were placed, each resting on one,
two, or three of the taller glands. In the course of 2 hrs. 30 m. the
secretion was all absorbed, and the shreds were left almost dry. They
[page 341] were then pushed on to the sessile glands. One shred, after
2 hrs. 30 m., seemed quite dissolved, but this may have been a mistake.
A second, when examined after 17 hrs. 25 m., was liquefied, but the
liquid as seen under the microscope still contained floating granules
of fibrin. The other two shreds were completely liquefied after 21 hrs.
30 m.; but in one of the drops a very few granules could still be
detected. These, however, were dissolved after an additional interval
of 6 hrs. 30 m.; and the surface of the leaf for some distance all
round was covered with limpid fluid. It thus appears that Drosophyllum
digests albumen and fibrin rather more quickly than Drosera can; and
this may perhaps be attributed to the acid, together probably with some
small amount of the ferment, being present in the secretion, before the
glands have been stimulated; so that digestion begins at once.

Concluding Remarks.--The linear leaves of Drosophyllum differ but
slightly from those of certain species of Drosera; the chief
differences being, firstly, the presence of minute, almost sessile,
glands, which, like those of Dionaea, do not secrete until they are
excited by the absorption of nitrogenous matter. But glands of this
kind are present on the leaves of Drosera binata, and appear to be
represented by the papillae on the leaves of Drosera rotundifolia.
Secondly, the presence of tentacles on the backs of the leaves; but we
have seen that a few tentacles, irregularly placed and tending towards
abortion, are retained on the backs of the leaves of Drosera binata.
There are greater differences in function between the two genera.  The
most important one is that the tentacles of Drosophyllum have no power
of movement; this loss being partially replaced by the drops of viscid
[page 342] secretion being readily withdrawn from the glands; so that,
when an insect comes into contact with a drop, it is able to crawl
away, but soon touches other drops, and then, smothered by the
secretion, sinks down on the sessile glands and dies. Another
difference is, that the secretion from the tall glands, before they
have been in any way excited, is strongly acid, and perhaps contains a
small quantity of the proper ferment. Again, these glands do not
secrete more copiously from being excited by the absorption of
nitrogenous matter; on the contrary, they then absorb their own
secretion with extraordinary quickness. In a short time they begin to
secrete again. All these circumstances are probably connected with the
fact that insects do not commonly adhere to the glands with which they
first come into contact, though this does sometimes occur; and that it
is chiefly the secretion from the sessile glands which dissolves animal
matter out of their bodies.

                           RORIDULA.

Roridula dentata.--This plant, a native of the western parts of the
Cape of Good Hope, was sent to me in a dried state from Kew. It has an
almost woody stem and branches, and apparently grows to a height of
some feet. The leaves are linear, with their summits much attenuated.
Their upper and lower surfaces are concave, with a ridge in the middle,
and both are covered with tentacles, which differ greatly in length;
some being very long, especially those on the tips of the leaves, and
some very short. The glands also differ much in size and are somewhat
elongated. They are supported on multicellular pedicels.

This plant, therefore, agrees in several respects with [page 343]
Drosophyllum, but differs in the following points. I could detect no
sessile glands; nor would these have been of any use, as the upper
surface of the leaves is thickly clothed with pointed, unicellular
hairs directed upwards. The pedicels of the tentacles do not include
spiral vessels; nor are there any spiral cells within the glands. The
leaves often arise in tufts and are pinnatifid, the divisions
projecting at right angles to the main linear blade. These lateral
divisions are often very short and bear only a single terminal
tentacle, with one or two short ones on the sides. No distinct line of
demarcation can be drawn between the pedicels of the long terminal
tentacles and the much attenuated summits of the leaves. We may,
indeed, arbitrarily fix on the point to which the spiral vessels
proceeding from the blade extend; but there is no other distinction.

It was evident from the many particles of dirt sticking to the glands
that they secrete much viscid matter. A large number of insects of many
kinds also adhered to the leaves. I could nowhere discover any signs of
the tentacles having been inflected over the captured insects; and this
probably would have been seen even in the dried specimens, had they
possessed the power of movement. Hence, in this negative character,
Roridula resembles its northern representative, Drosophyllum.

                            BYBLIS.

Byblis gigantea (Western Australia).--A dried specimen, about 18 inches
in height, with a strong stem, was sent me from Kew. The leaves are
some inches in length, linear, slightly flattened, with a small
projecting rib on the lower surface. They are covered on all sides by
glands of two kinds [page 344] --sessile ones arranged in rows, and
others supported on moderately long pedicels. Towards the narrow
summits of the leaves the pedicels are longer than elsewhere, and here
equal the diameter of the leaf. The glands are purplish, much
flattened, and formed of a single layer of radiating cells, which in
the larger glands are from forty to fifty in number. The pedicels
consist of single elongated cells, with colourless, extremely delicate
walls, marked with the finest intersecting spiral lines. Whether these
lines are the result of contraction from the drying of the walls, I do
not know, but the whole pedicel was often spirally rolled up. These
glandular hairs are far more simple in structure than the so-called
tentacles of the preceding genera, and they do not differ essentially
from those borne by innumerable other plants. The flower-peduncles bear
similar glands. The most singular character about the leaves is that
the apex is enlarged into a little knob, covered with glands, and about
a third broader than the adjoining part of the attenuated leaf. In two
places dead flies adhered to the glands. As no instance is known of
unicellular structures having any power of movement,* Byblis, no doubt,
catches insects solely by the aid of its viscid secretion. These
probably sink down besmeared with the secretion and rest on the small
sessile glands, which, if we may judge by the analogy of Drosophyllum,
then pour forth their secretion and afterwards absorb the digested
matter.

Supplementary Observations on the Power of Absorption by the Glandular
Hairs of other Plants.--A few observations on this subject may be here
conveniently introduced. As the glands of many, probably of all,

* Sachs, 'Trait de Bot.,' 3rd edit. 1874, p. 1026.  [page 345]

the species of Droseraceae absorb fluids or at least allow them readily
to enter,* it seemed desirable to ascertain how far the glands of other
plants which are not specially adapted for capturing insects, had the
same power. Plants were chosen for trial at hazard, with the exception
of two species of saxifrage, which were selected from belonging to a
family allied to the Droseraceae. Most of the experiments were made by
immersing the glands either in an infusion of raw meat or more commonly
in a solution of carbonate of ammonia, as this latter substance acts so
powerfully and rapidly on protoplasm. It seemed also particularly
desirable to ascertain whether ammonia was absorbed, as a small amount
is contained in rain-water.  With the Droseraceae the secretion of a
viscid fluid by the glands does not prevent their absorbing; so that
the glands of other plants might excrete superfluous matter, or secrete
an odoriferous fluid as a protection against the attacks of insects, or
for any other purpose, and yet have the power of absorbing. I regret
that in the following cases I did not try whether the secretion could
digest or render soluble animal substances, but such experiments would
have been difficult on account of the small size of the glands and the
small amount of secretion.  We shall see in the next chapter that the
secretion from the glandular hairs of Pinguicula certainly dissolves
animal matter.

[Saxifraga umbrosa.--The flower-peduncles and petioles of the leaves
are clothed with short hairs, bearing pink-coloured glands, formed of
several polygonal cells, with their pedicels divided by partitions into
distinct cells, which are generally colourless, but sometimes pink.
The glands secrete a yellowish viscid fluid, by

*The distinction between true absorption and mere permeation, or
imbibition, is by no means clearly understood: see Mller's
'Physiology,' Eng. translat. 1838, vol. i. p. 280.  [page 346]

which minute Diptera are sometimes, though not often, caught.* The
cells of the glands contain bright pink fluid, charged with granules or
with globular masses of pinkish pulpy matter. This matter must be
protoplasm, for it is seen to undergo slow but incessant changes of
form if a gland be placed in a drop of water and examined. Similar
movements were observed after glands had been immersed in water for 1,
3, 5, 18, and 27 hrs. Even after this latter period the glands retained
their bright pink colour; and the protoplasm within their cells did not
appear to have become more aggregated. The continually changing forms
of the little masses of protoplasm are not due to the absorption of
water, as they were seen in glands kept dry.

A flower-stem, still attached to a plant, was bent (May 29) so as to
remain immersed for 23 hrs. 30 m. in a strong infusion of raw meat. The
colour of the contents of the glands was slightly changed, being now of
a duller and more purple tint than before. The contents also appeared
more aggregated, for the spaces between the little masses of protoplasm
were wider; but this latter result did not follow in some other and
similar experiments. The masses seemed to change their forms more
rapidly than did those in water; so that the cells had a different
appearance every four or five minutes. Elongated masses became in the
course of one or two minutes spherical; and spherical ones drew
themselves out and united with others.  Minute masses rapidly increased
in size, and three distinct ones were seen to unite. The movements
were, in short, exactly like those described in the case of Drosera.
The cells of the pedicels were not affected by the infusion; nor were
they in the following experiment.

Another flower-stem was placed in the same manner and for the same
length of time in a solution of one part of nitrate of ammonia to 146
of water (or 3 grs. to 1 oz.), and the glands were discoloured in
exactly the same manner as by the infusion of raw meat.

Another flower-stem was immersed, as before, in a solution of one part
of carbonate of ammonia to 109 of water. The glands, after 1 hr. 30 m.,
were not discoloured, but after 3 hrs.  45 m. most of them had become
dull purple, some of them blackish-

*In the case of Saxifraga tridactylites, Mr. Druce says
('Pharmaceutical Journal, ' May 1875) that he examined some dozens of
plants, and in almost every instance remnants of insects adhered to the
leaves. So it is, as I hear from a friend, with this plant in Ireland.
[page 347]

green, a few being still unaffected. The little masses of protoplasm
within the cells were seen in movement. The cells of the pedicels were
unaltered. The experiment was repeated, and a fresh flower-stem was
left for 23 hrs. in the solution, and now a great effect was produced;
all the glands were much blackened, and the previously transparent
fluid in the cells of the pedicels, even down to their bases, contained
spherical masses of granular matter. By comparing many different hairs,
it was evident that the glands first absorb the carbonate, and that the
effect thus produced travels down the hairs from cell to cell. The
first change which could be observed is a cloudy appearance in the
fluid, due to the formation of very fine granules, which afterwards
aggregate into larger masses. Altogether, in the darkening of the
glands, and in the process of aggregation travelling down the cells of
the pedicels, there is the closest resemblance to what takes place when
a tentacle of Drosera is immersed in a weak solution of the same salt.
The glands, however, absorb very much more slowly than those of
Drosera. Besides the glandular hairs, there are star-shaped organs
which do not appear to secrete, and which were not in the least
affected by the above solutions.

Although in the case of uninjured flower-stems and leaves the carbonate
seems to be absorbed only by the glands, yet it enters a cut surface
much more quickly than a gland.  Strips of the rind of a flower-stem
were torn off, and the cells of the pedicels were seen to contain only
colourless transparent fluid; those of the glands including as usual
some granular matter. These strips were then immersed in the same
solution as before (one part of the carbonate to 109 of water), and in
a few minutes granular matter appeared in the lowercells of all the
pedicels. The action invariably commenced (for I tried the experiment
repeatedly) in the lowest cells, and therefore close to the torn
surface, and then gradually travelled up the hairs until it reached the
glands, in a reversed direction to what occurs in uninjured specimens.
The glands then became discoloured, and the previously contained
granular matter was aggregated into larger masses. Two short bits of a
flower-stem were also left for 2 hrs. 40 m. in a weaker solution of one
part of the carbonate to 218 of water; and in both specimens the
pedicels of the hairs near the cut ends now contained much granular
matter; and the glands were completely discoloured.

Lastly, bits of meat were placed on some glands; these were examined
after 23 hrs., as were others, which had apparently not long before
caught minute flies; but they did not present any [page 348] difference
from the glands of other hairs. Perhaps there may not have been time
enough for absorption. I think so as some glands, on which dead flies
had evidently long lain, were of a pale dirty purple colour or even
almost colourless, and the granular matter within them presented an
unusual and somewhat peculiar appearance. That these glands had
absorbed animal matter from the flies, probably by exosmose into the
viscid secretion, we may infer, not only from their changed colour, but
because, when placed in a solution of carbonate of ammonia, some of the
cells in their pedicels become filled with granular matter; whereas the
cells of other hairs, which had not caught flies, after being treated
with the same solution for the same length of time, contained only a
small quantity of granular matter. But more evidence is necessary
before we fully admit that the glands of this saxifrage can absorb,
even with ample time allowed, animal matter from the minute insects
which they occasionally and accidentally capture.

Saxifraga rotundifolia (?).--The hairs on the flower-stems of this
species are longer than those just described, and bear pale brown
glands. Many were examined, and the cells of the pedicels were quite
transparent. A bent stem was immersed for 30 m. in a solution of one
part of carbonate of ammonia to 109 of water, and two or three of the
uppermost cells in the pedicels now contained granular or aggregated
matter; the glands having become of a bright yellowish-green. The
glands of this species therefore absorb the carbonate much more quickly
than do those of Saxifraga umbrosa, and the upper cells of the pedicels
are likewise affected much more quickly. Pieces of the stem were cut
off and immersed in the same solution; and now the process of
aggregation travelled up the hairs in a reversed direction; the cells
close to the cut surfaces being first affected.

Primula sinensis.--The flower-stems, the upper and lower surfaces of
the leaves and their footstalks, are all clothed with a multitude of
longer and shorter hairs. The pedicels of the longer hairs are divided
by transverse partitions into eight or nine cells. The enlarged
terminal cell is globular, forming a gland which secretes a variable
amount of thick, slightly viscid, not acid, brownish-yellow matter.

A piece of a young flower-stem was first immersed in distilled water
for 2 hrs. 30 m., and the glandular hairs were not at all affected.
Another piece, bearing twenty-five short and nine long hairs, was
carefully examined. The glands of the latter contained no solid or
semi-solid matter; and those of only two [page 349] of the twenty-five
short hairs contained some globules. This piece was then immersed for 2
hrs. in a solution of one part of carbonate of ammonia to 109 of water,
and now the glands of the twenty-five shorter hairs, with two or three
exceptions, contained either one large or from two to five smaller
spherical masses of semi-solid matter. Three of the glands of the nine
long hairs likewise included similar masses. In a few hairs there were
also globules in the cells immediately beneath the glands. Looking to
all thirty-four hairs, there could be no doubt that the glands had
absorbed some of the carbonate. Another piece was left for only 1 hr.
in the same solution, and aggregated matter appeared in all the glands.
My son Francis examined some glands of the longer hairs, which
contained little masses of matter, before they were immersed in any
solution; and these masses slowly changed their forms, so that no doubt
they consisted of protoplasm. He then irrigated these hairs for 1 hr.
15 m., whilst under the microscope, with a solution of one part of the
carbonate to 218 of water; the glands were not perceptibly affected,
nor could this have been expected, as their contents were already
aggregated. But in the cells of the pedicels numerous, almost
colourless, spheres of matter appeared, which changed their forms and
slowly coalesced; the appearance of the cells being thus totally
changed at successive intervals of time.

The glands on a young flower-stem, after having been left for 2 hrs. 45
m. in a strong solution of one part of the carbonate to 109 of water,
contained an abundance of aggregated masses, but whether generated by
the action of the salt, I do not know. This piece was again placed in
the solution, so that it was immersed altogether for 6 hrs. 15 m., and
now there was a great change; for almost all the spherical masses
within the gland-cells had disappeared, being replaced by granular
matter of a darker brown. The experiment was thrice repeated with
nearly the same result. On one occasion the piece was left immersed for
8 hrs. 30 m., and though almost all the spherical masses were changed
into the brown granular matter, a few still remained. If the spherical
masses of aggregated matter had been originally produced merely by some
chemical or physical action, it seems strange that a somewhat longer
immersion in the same solution should so completely alter their
character. But as the masses which slowly and spontaneously changed
their forms must have consisted of living protoplasm, there is nothing
surprising in its being injured or killed, and its appearance wholly
changed by long immersion in so strong a solution of the carbonate as
that [page 350] employed. A solution of this strength paralyses all
movement in Drosera, but does not kill the protoplasm; a still stronger
solution prevents the protoplasm from aggregating into the ordinary
full-sized globular masses, and these, though they do not disintegrate,
become granular and opaque. In nearly the same manner, too hot water
and certain solutions (for instance, of the salts of soda and potash)
cause at first an imperfect kind of aggregation in the cells of
Drosera; the little masses afterwards breaking up into granular or
pulpy brown matter. All the foregoing experiments were made on
flower-stems, but a piece of a leaf was immersed for 30 m. in a strong
solution of the carbonate (one part to 109 of water), and little
globular masses of matter appeared in all the glands, which before
contained only limpid fluid.

I made also several experiments on the action of the vapour of the
carbonate on the glands; but will give only a few cases. The cut end of
the footstalk of a young leaf was protected with sealing-wax, and was
then placed under a small bell-glass, with a large pinch of the
carbonate. After 10 m. the glands showed a considerable degree of
aggregation, and the protoplasm lining the cells of the pedicels was a
little separated from the walls. Another leaf was left for 50 m. with
the same result, excepting that the hairs became throughout their whole
length of a brownish colour. In a third leaf, which was exposed for 1
hr. 50 m., there was much aggregated matter in the glands; and some of
the masses showed signs of breaking up into brown granular matter. This
leaf was again placed in the vapour, so that it was exposed altogether
for 5 hrs. 30 m.; and now, though I examined a large number of glands,
aggregated masses were found in only two or three; in all the others,
the masses, which before had been globular, were converted into brown,
opaque, granular matter. We thus see that exposure to the vapour for a
considerable time produces the same effects as long immersion in a
strong solution. In both cases there could hardly be a doubt that the
salt had been absorbed chiefly or exclusively by the glands.

On another occasion bits of damp fibrin, drops of a weak infusion of
raw meat and of water, were left for 24 hrs. on some leaves; the hairs
were then examined, but to my surprise differed in no respect from
others which had not been touched by these fluids. Most of the cells,
however, included hyaline, motionless little spheres, which did not
seem to consist of protoplasm, but, I suppose, of some balsam or
essential oil.

Pelargonium zonale (var. edged with white).--The leaves [page 351] are
clothed with numerous multicellular hairs; some simply pointed; others
bearing glandular heads, and differing much in length. The glands on a
piece of leaf were examined and found to contain only limpid fluid;
most of the water was removed from beneath the covering glass, and a
minute drop of one part of carbonate of ammonia to 146 of water was
added; so that an extremely small dose was given. After an interval of
only 3 m. there were signs of aggregation within the glands of the
shorter hairs; and after 5 m. many small globules of a pale brown tint
appeared in all of them; similar globules, but larger, being found in
the large glands of the longer hairs. After the specimen had been left
for 1 hr. in the solution, many of the smaller globules had changed
their positions; and two or three vacuoles or small spheres (for I know
not which they were) of a rather darker tint appeared within some of
the larger globules. Little globules could now be seen in some of the
uppermost cells of the pedicels, and the protoplasmic lining was
slightly separated from the walls of the lower cells. After 2 hrs. 30
m. from the time of first immersion, the large globules within the
glands of the longer hairs were converted into masses of darker brown
granular matter. Hence from what we have seen with Primula sinensis,
there can be little doubt that these masses originally consisted of
living protoplasm.

A drop of a weak infusion of raw meat was placed on a leaf, and after 2
hrs. 30 m. many spheres could be seen within the glands. These spheres,
when looked at again after 30 m., had slightly changed their positions
and forms, and one had separated into two; but the changes were not
quite like those which the protoplasm of Drosera undergoes. These
hairs, moreover, had not been examined before immersion, and there were
similar spheres in some glands which had not been touched by the
infusion.

Erica tetralix.--A few long glandular hairs project from the margins of
the upper surfaces of the leaves. The pedicels are formed of several
rows of cells, and support rather large globular heads, secreting
viscid matter, by which minute insects are occasionally, though rarely,
caught. Some leaves were left for 23 hrs. in a weak infusion of raw
meat and in water, and the hairs were then compared, but they differed
very little or not at all. In both cases the contents of the cells
seemed rather more granular than they were before; but the granules did
not exhibit any movement. Other leaves were left for 23 hrs. in a
solution of one part of carbonate of ammonia to 218 of water, and here
again the granular matter appeared to have increased [page 352] in
amount; but one such mass retained exactly the same form as before
after an interval of 5 hrs., so that it could hardly have consisted of
living protoplasm. These glands seem to have very little or no power of
absorption, certainly much less than those of the foregoing plants.

Mirabilis longiflora.--The stems and both surfaces of the leaves bear
viscid hairs. young plants, from 12 to 18 inches in height in my
greenhouse, caught so many minute Diptera, Coleoptera, and larvae, that
they were quite dusted with them. The hairs are short, of unequal
lengths, formed of a single row of cells, surmounted by an enlarged
cell which secretes viscid matter. These terminal cells or glands
contain granules and often globules of granular matter.  Within a gland
which had caught a small insect, one such mass was observed to undergo
incessant changes of form, with the occasional appearance of vacuoles.
But I do not believe that this protoplasm had been generated by matter
absorbed from the dead insect; for, on comparing several glands which
had and had not caught insects, not a shade of difference could be
perceived between them, and they all contained fine granular matter. A
piece of leaf was immersed for 24 hrs. in a solution of one part of
carbonate of ammonia to 218 of water, but the hairs seemed very little
affected by it, excepting that perhaps the glands were rendered rather
more opaque. In the leaf itself, however, the grains of chlorophyll
near the cut surfaces had run together, or become aggregated. Nor were
the glands on another leaf, after an immersion for 24 hrs. in an
infusion of raw meat, in the least affected; but the protoplasm lining
the cells of the pedicels had shrunk greatly from the walls. This
latter effect may have been due to exosmose, as the infusion was
strong. We may, therefore, conclude that the glands of this plant
either have no power of absorption or that the protoplasm which they
contain is not acted on by a solution of carbonate of ammonia (and this
seems scarcely credible) or by an infusion of meat.

Nicotiana tabacum.--This plant is covered with innumerable hairs of
unequal lengths, which catch many minute insects. The pedicels of the
hairs are divided by transverse partitions, and the secreting glands
are formed of many cells, containing greenish matter with little
globules of some substance. Leaves were left in an infusion of raw meat
and in water for 26 hrs., but presented no difference. Some of these
same leaves were then left for above 2 hrs. in a solution of carbonate
of ammonia, but no effect was produced. I regret that other experiments
were not tried with more care, as M. Schloesing [page 353] has shown*
that tobacco plants supplied with the vapour of carbonate of ammonia
yield on analysis a greater amount of nitrogen than other plants not
thus treated; and, from what we have seen, it is probable that some of
the vapour may be absorbed by the glandular hairs.]

Summary of the Observations on Glandular Hairs.--From the foregoing
observations, few as they are, we see that the glands of two species of
Saxifraga, of a Primula and Pelargonium, have the power of rapid
absorption; whereas the glands of an Erica, Mirabilis, and Nicotiana,
either have no such power, or the contents of the cells are not
affected by the fluids employed, namely a solution of carbonate of
ammonia and an infusion of raw meat. As the glands of the Mirabilis
contain protoplasm, which did not become aggregated from exposure to
the fluids just named, though the contents of the cells in the blade of
the leaf were greatly affected by carbonate of ammonia, we may infer
that they cannot absorb. We may further infer that the innumerable
insects caught by this plant are of no more service to it than are
those which adhere to the deciduous and sticky scales of the leaf-buds
of the horse-chestnut.

The most interesting case for us is that of the two species of
Saxifraga, as this genus is distantly allied to Drosera. Their glands
absorb matter from an infusion of raw meat, from solutions of the
nitrate and carbonate of ammonia, and apparently from decayed insects.
This was shown by the changed dull purple colour of the protoplasm
within the cells of the glands, by its state of aggregation, and
apparently by its more rapid spontaneous movements.

* 'Comptes rendus,' June 15, 1874. A good abstract of this paper is
given in the 'Gardener's Chronicle,' July 11, 1874.  [page 354]

The aggregating process spreads from the glands down the pedicels of
the hairs; and we may assume that any matter which is absorbed
ultimately reaches the tissues of the plant. On the other hand, the
process travels up the hairs whenever a surface is cut and exposed to a
solution of the carbonate of ammonia.

The glands on the flower-stalks and leaves of Primula sinensis quickly
absorb a solution of the carbonate of ammonia, and the protoplasm which
they contain becomes aggregated. The process was seen in some cases to
travel from the glands into the upper cells of the pedicels.  Exposure
for 10 m. to the vapour of this salt likewise induced aggregation. When
leaves were left from 6 hrs. to 7 hrs. in a strong solution, or were
long exposed to the vapour, the little masses of protoplasm became
disintegrated, brown, and granular, and were apparently killed.  An
infusion of raw meat produced no effect on the glands.

The limpid contents of the glands of Pelargonium zonale became cloudy
and granular in from 3 m. to 5 m. when they were immersed in a weak
solution of the carbonate of ammonia; and in the course of 1 hr.
granules appeared in the upper cells of the pedicels. As the aggregated
masses slowly changed their forms, and as they suffered disintegration
when left for a considerable time in a strong solution, there can be
little doubt that they consisted of protoplasm. It is doubtful whether
an infusion of raw meat produced any effect.

The glandular hairs of ordinary plants have generally been considered
by physiologists to serve only as secreting or excreting organs, but we
now know that they have the power, at least in some cases, of absorbing
both a solution and the vapour of ammonia. As rain-water contains a
small percentage of ammonia, and the atmosphere a minute quantity of
the carbonate, this [page 355] power can hardly fail to be beneficial.
Nor can the benefit be quite so insignificant as it might at first be
thought, for a moderately fine plant of Primula sinensis bears the
astonishing number of above two millions and a half of glandular
hairs,* all of which are able to absorb ammonia brought to them by the
rain. It is moreover probable that the glands of some of the above
named plants obtain animal matter from the insects which are
occasionally entangled by the viscid secretion.

            CONCLUDING REMARKS ON THE DROSERACEAE.

The six known genera composing this family have now been described in
relation to our present subject, as far as my means have permitted.
They all capture insects. This is effected by Drosophyllum, Roridula,
and Byblis, solely by the viscid fluid secreted from their glands; by
Drosera, through the same means, together with the movements of the
tentacles; by Dionaea and Aldrovanda, through the closing of the blades
of the leaf. In these two last genera rapid

* My son Francis counted the hairs on a space measured by means of a
micrometer, and found that there were 35,336 on a square inch of the
upper surface of a leaf, and 30,035 on the lower surface; that is, in
about the proportion of 100 on the upper to 85 on the lower surface. On
a square inch of both surfaces there were 65,371 hairs. A moderately
fine plant bearing twelve leaves (the larger ones being a little more
than 2 inches in diameter) was now selected, and the area of all the
leaves, together with their foot-stalks (the flower-stems not being
included), was found by a planimeter to be 39.285 square inches; so
that the area of both surfaces was 78.57 square inches. Thus the plant
(excluding the flower-stems) must have borne the astonishing number of
2,568,099 glandular hairs. The hairs were counted late in the autumn,
and by the following spring (May) the leaves of some other plants of
the same lot were found to be from one-third to one-fourth broader and
longer than they were before; so that no doubt the glandular hairs had
increased in number, and probably now much exceeded three millions.
[page 356]

movement makes up for the loss of viscid secretion. In every case it is
some part of the leaf which moves. In Aldrovanda it appears to be the
basal parts alone which contract and carry with them the broad, thin
margins of the lobes. In Dionaea the whole lobe, with the exception of
the marginal prolongations or spikes, curves inwards, though the chief
seat of movement is near the midrib. In Drosera the chief seat is in
the lower part of the tentacles, which, homologically, may be
considered as prolongations of the leaf; but the whole blade often
curls inwards, converting the leaf into a temporary stomach.

There can hardly be a doubt that all the plants belonging to these six
genera have the power of dissolving animal matter by the aid of their
secretion, which contains an acid, together with a ferment almost
identical in nature with pepsin; and that they afterwards absorb the
matter thus digested. This is certainly the case with Drosera,
Drosophyllum, and Dionaea; almost certainly with Aldrovanda; and, from
analogy, very probable with Roridula and Byblis. We can thus understand
how it is that the three first-named genera are provided with such
small roots, and that Aldrovanda is quite rootless; about the roots of
the two other genera nothing is known. It is, no doubt, a surprising
fact that a whole group of plants (and, as we shall presently see, some
other plants not allied to the Droseraceae) should subsist partly by
digesting animal matter, and partly by decomposing carbonic acid,
instead of exclusively by this latter means, together with the
absorption of matter from the soil by the aid of roots. We have,
however, an equally anomalous case in the animal kingdom; the
rhizocephalous crustaceans do not feed like other animals by their
mouths, for they are destitute of an [page 357] alimentary canal; but
they live by absorbing through root-like processes the juices of the
animals on which they are parasitic.*

Of the six genera, Drosera has been incomparably the most successful in
the battle for life; and a large part of its success may be attributed
to its manner of catching insects. It is a dominant form, for it is
believed to include about 100 species,  which range in the Old World
from the Arctic regions to Southern India, to the Cape of Good Hope,
Madagascar, and Australia; and in the New World from Canada to Tierra
del Fuego. In this respect it presents a marked contrast with the five
other genera, which appear to be failing groups.  Dionaea includes only
a single species, which is confined to one district in Carolina. The
three varieties or closely allied species of Aldrovanda, like so many
water-plants, have a wide range from Central Europe to Bengal and
Australia. Drosophyllum includes only one species, limited to Portugal
and Morocco. Roridula and Byblis each have (as I

* Fritz Mller, 'Facts for Darwin, ' Eng. trans. 1869, p. 139. The
rhizocephalous crustaceans are allied to the cirripedes. It is hardly
possible to imagine a greater difference than that between an animal
with prehensile limbs, a well-constructed mouth and alimentary canal,
and one destitute of all these organs and feeding by absorption through
branching root-like processes. If one rare cirripede, the Anelasma
squalicola, had become extinct, it would have been very difficult to
conjecture how so enormous a change could have been gradually effected.
But, as Fritz Mller remarks, we have in Anelasma an animal in an almost
exactly intermediate condition, for it has root-like processes embedded
in the skin of the shark on which it is parasitic, and its prehensile
cirri and mouth (as described in my monograph on the Lepadidae, 'Ray
Soc.' 1851, p. 169) are in a most feeble and almost rudimentary
condition.  Dr. R. Kossmann has given a very interesting discussion on
this subject in his 'Suctoria and Lepadidae,' 1873. See also, Dr.
Dohrn, 'Der Ursprung der Wirbelthiere,' 1875, p. 77.

  Bentham and Hooker, 'Genera Plantarum.' Australia is the metropolis
  of the genus, forty-one species having been described from this
country, as Prof. Oliver informs me.  [page 358]

hear from Prof. Oliver) two species; the former confined to the western
parts of the Cape of Good Hope, and the latter to Australia. It is a
strange fact that Dionaea, which is one of the most beautifully adapted
plants in the vegetable kingdom, should apparently be on the high-road
to extinction. This is all the more strange as the organs of Dionaea
are more highly differentiated than those of Drosera; its filaments
serve exclusively as organs of touch, the lobes for capturing insects,
and the glands, when excited, for secretion as well as for absorption;
whereas with Drosera the glands serve all these purposes, and secrete
without being excited.

By comparing the structure of the leaves, their degree of complication,
and their rudimentary parts in the six genera, we are led to infer that
their common parent form partook of the characters of Drosophyllum,
Roridula, and Byblis. The leaves of this ancient form were almost
certainly linear, perhaps divided, and bore on their upper and lower
surfaces glands which had the power of secreting and absorbing. Some of
these glands were mounted on pedicels, and others were almost sessile;
the latter secreting only when stimulated by the absorption of
nitrogenous matter. In Byblis the glands consist of a single layer of
cells, supported on a unicellular pedicel; in Roridula they have a more
complex structure, and are supported on pedicels formed of several rows
of cells; in Drosophyllum they further include spiral cells, and the
pedicels include a bundle of spiral vessels. But in these three genera
these organs do not possess any power of movement, and there is no
reason to doubt that they are of the nature of hairs or trichomes.
Although in innumerable instances foliar organs move when excited, no
case is known of a trichome having such [page 359] power.* We are thus
led to inquire how the so-called tentacles of Drosera, which are
manifestly of the same general nature as the glandular hairs of the
above three genera, could have acquired the power of moving. Many
botanists maintain that these tentacles consist of prolongations of the
leaf, because they include vascular tissue, but this can no longer be
considered as a trustworthy distinction.  The possession of the power
of movement on excitement would have been safer evidence. But when we
consider the vast number of the tentacles on both surfaces of the
leaves of Drosophyllum, and on the upper surface of the leaves of
Drosera, it seems scarcely possible that each tentacle could have
aboriginally existed as a prolongation of the leaf. Roridula, perhaps,
shows us how we may reconcile these difficulties with respect to the
homological nature of the tentacles. The lateral divisions of the
leaves of this plant terminate in long tentacles; and these include
spiral vessels which extend for only a short distance up them, with no
line of demarcation between what is plainly the prolongation of the
leaf and the pedicel of a glandular hair. Therefore there would be
nothing anomalous or unusual in the basal parts of these tentacles,
which correspond with the marginal ones of Drosera, acquiring the power
of movement; and we know that in Drosera it is only the lower part
which becomes inflected. But in order to understand how in this latter
genus not only the marginal but all the inner tentacles have become
capable of movement, we must further assume, either that through the
principle of correlated development this

* Sachs, 'Trait de Botanique' 3rd edit. 1874, p. 1026.

  Dr. Warming 'Sur la Diffrence entres les Trichomes,' Copenhague,
  1873, p. 6. 'Extrait des Videnskabelige Meddelelser de la Soc.
d'Hist. nat. de Copenhague,' Nos. 10-12, 1872.  [page 360]

power was transferred to the basal parts of the hairs, or that the
surface of the leaf has been prolonged upwards at numerous points, so
as to unite with the hairs, thus forming the bases of the inner
tentacles.

The above named three genera, namely Drosophyllum, Roridula, and
Byblis, which appear to have retained a primordial condition, still
bear glandular hairs on both surfaces of their leaves; but those on the
lower surface have since disappeared in the more highly developed
genera, with the partial exception of one species, Drosera binata. The
small sessile glands have also disappeared in some of the genera, being
replaced in Roridula by hairs, and in most species of Drosera by
absorbent papillae. Drosera binata, with its linear and bifurcating
leaves, is in an intermediate condition. It still bears some sessile
glands on both surfaces of the leaves, and on the lower surface a few
irregularly placed tentacles, which are incapable of movement. A
further slight change would convert the linear leaves of this latter
species into the oblong leaves of Drosera anglica, and these might
easily pass into orbicular ones with footstalks, like those of Drosera
rotundifolia. The footstalks of this latter species bear multicellular
hairs, which we have good reason to believe represent aborted
tentacles.

The parent form of Dionaea and Aldrovanda seems to have been closely
allied to Drosera, and to have had rounded leaves, supported on
distinct footstalks, and furnished with tentacles all round the
circumference, with other tentacles and sessile glands on the upper
surface. I think so because the marginal spikes of Dionaea apparently
represent the extreme marginal tentacles of Drosera, the six (sometimes
eight) sensitive filaments on the upper surface, as well as the more
numerous ones in Aldrovanda, representing the central [page 361]
tentacles of Drosera, with their glands aborted, but their
sensitiveness retained. Under this point of view we should bear in mind
that the summits of the tentacles of Drosera, close beneath the glands,
are sensitive.

The three most remarkable characters possessed by the several members
of the Droseraceae consist in the leaves of some having the power of
movement when excited, in their glands secreting a fluid which digests
animal matter, and in their absorption of the digested matter.  Can any
light be thrown on the steps by which these remarkable powers were
gradually acquired?

As the walls of the cells are necessarily permeable to fluids, in order
to allow the glands to secrete, it is not surprising that they should
readily allow fluids to pass inwards; and this inward passage would
deserve to be called an act of absorption, if the fluids combined with
the contents of the glands. Judging from the evidence above given, the
secreting glands of many other plants can absorb salts of ammonia, of
which they must receive small quantities from the rain. This is the
case with two species of Saxifraga, and the glands of one of them
apparently absorb matter from captured insects, and certainly from an
infusion of raw meat.  There is, therefore, nothing anomalous in the
Droseraceae having acquired the power of absorption in a much more
highly developed degree.

It is a far more remarkable problem how the members of this family, and
Pinguicula, and, as Dr. Hooker has recently shown, Nepenthes, could all
have acquired the power of secreting a fluid which dissolves or digests
animal matter. The six genera of the Droseraceae very probably
inherited this power from a common progenitor, but this cannot apply to
[page 362] Pinguicula or Nepenthes, for these plants are not at all
closely related to the Droceraceae. But the difficulty is not nearly so
great as it at first appears. Firstly, the juices of many plants
contain an acid, and, apparently, any acid serves for digestion.
Secondly, as Dr. Hooker has remarked in relation to the present subject
in his address at Belfast (1874), and as Sachs repeatedly insists,* the
embryos of some plants secrete a fluid which dissolves albuminous
substances out of the endosperm; although the endosperm is not actually
united with, only in contact with, the embryo. All plants, moreover,
have the power of dissolving albuminous or proteid substances, such as
protoplasm, chlorophyll, gluten, aleurone, and of carrying them from
one part to other parts of their tissues. This must be effected by a
solvent, probably consisting of a ferment together with an acid.  Now,
in the case of plants which are able to absorb already soluble matter
from captured insects, though not capable of true digestion, the
solvent just referred to, which must be occasionally present in the
glands, would be apt to exude from the glands together with the viscid
secretion, inasmuch as endosmose is accompanied by exosmose. If such
exudation did ever occur, the solvent would act on the animal matter
contained within the captured insects, and this would be an act of true
digestion. As it cannot be doubted that this process would be of high
service to plants

* 'Trait de Botanique' 3rd edit. 1874, p. 844. See also for following
facts pp. 64, 76, 828, 831.

  Since this sentence was written, I have received a paper by
  Gorup-Besanez ('Berichte der Deutschen Chem. Gesellschaft,' Berlin,
1874, p. 1478), who, with the aid of Dr. H. Will, has actually made the
discovery that the seeds of the vetch contain a ferment, which, when
extracted by glycerine, dissolves albuminous substances, such as
fibrin, and converts them into true peptones.  [page 363]

growing in very poor soil, it would tend to be perfected through
natural selection. Therefore, any ordinary plant having viscid glands,
which occasionally caught insects, might thus be converted under
favourable circumstances into a species capable of true digestion. It
ceases, therefore, to be any great mystery how several genera of
plants, in no way closely related together, have independently acquired
this same power.

As there exist several plants the glands of which cannot, as far as is
known, digest animal matter, yet can absorb salts of ammonia and animal
fluids, it is probable that this latter power forms the first stage
towards that of digestion. It might, however, happen, under certain
conditions, that a plant, after having acquired the power of digestion,
should degenerate into one capable only of absorbing animal matter in
solution, or in a state of decay, or the final products of decay,
namely the salts of ammonia. It would appear that this has actually
occurred to a partial extent with the leaves of Aldrovanda; the outer
parts of which possess absorbent organs, but no glands fitted for the
secretion of any digestive fluid, these being confined to the inner
parts.

Little light can be thrown on the gradual acquirement of the third
remarkable character possessed by the more highly developed genera of
the Droseraceae, namely the power of movement when excited. It should,
however, be borne in mind that leaves and their homologues, as well as
flower-peduncles, have gained this power, in innumerable instances,
independently of inheritance from any common parent form; for instance,
in tendril-bearers and leaf-climbers (i.e. plants with their leaves,
petioles and flower-peduncles, &c., modified for prehension) belonging
to a large [page 364] number of the most widely distinct orders,--in
the leaves of the many plants which go to sleep at night, or move when
shaken,--and in the irritable stamens and pistils of not a few species.
We may therefore infer that the power of movement can be by some means
readily acquired. Such movements imply irritability or sensitiveness,
but, as Cohn has remarked,* the tissues of the plants thus endowed do
not differ in any uniform manner from those of ordinary plants; it is
therefore probable that all leaves are to a slight degree irritable.
Even if an insect alights on a leaf, a slight molecular change is
probably transmitted to some distance across its tissue, with the sole
difference that no perceptible effect is produced. We have some
evidence in favour of this belief, for we know that a single touch on
the glands of Drosera does not excite inflection; yet it must produce
some effect, for if the glands have been immersed in a solution of
camphor, inflection follows within a shorter time than would have
followed from the effects of camphor alone. So again with Dionaea, the
blades in their ordinary state may be roughly touched without their
closing; yet some effect must be thus caused and transmitted across the
whole leaf, for if the glands have recently absorbed animal matter,
even a delicate touch causes them to close instantly. On the whole we
may conclude that the acquirement of a high degree of sensitiveness and
of the power of movement by certain genera of the Droseraceae presents
no greater difficulty than that presented by the similar but feebler
powers of a multitude of other plants.

* See the abstract of his memoir on the contractile tissues of plants,
in the 'Annals and Mag.  of Nat. Hist.' 3rd series, vol. xi. p. 188.)
[page 365]

The specialised nature of the sensitiveness possessed by Drosera and
Dionaea, and by certain other plants, well deserves attention. A gland
of Drosera may be forcibly hit once, twice, or even thrice, without any
effect being produced, whilst the continued pressure of an extremely
minute particle excites movement. On the other hand, a particle many
times heavier may be gently laid on one of the filaments of Dionaea
with no effect; but if touched only once by the slow movement of a
delicate hair, the lobes close; and this difference in the nature of
the sensitiveness of these two plants stands in manifest adaptation to
their manner of capturing insects. So does the fact, that when the
central glands of Drosera absorb nitrogenous matter, they transmit a
motor impulse to the exterior tentacles much more quickly than when
they are mechanically irritated; whilst with Dionaea the absorption of
nitrogenous matter causes the lobes to press together with extreme
slowness, whilst a touch excites rapid movement.  Somewhat analogous
cases may be observed, as I have shown in another work, with the
tendrils of various plants; some being most excited by contact with
fine fibres, others by contact with bristles, others with a flat or a
creviced surface. The sensitive organs of Drosera and Dionaea are also
specialised, so as not to be uselessly affected by the weight or impact
of drops of rain, or by blasts of air. This may be accounted for by
supposing that these plants and their progenitors have grown accustomed
to the repeated action of rain and wind, so that no molecular change is
thus induced; whilst they have been rendered more sensitive by means of
natural selection to the rarer impact or pressure of solid bodies.
Although the absorption by the glands of Drosera of various fluids
excites move- [page 366] ment, there is a great difference in the
action of allied fluids; for instance, between certain vegetable acids,
and between citrate and phosphate of ammonia. The specialised nature
and perfection of the sensitiveness in these two plants is all the more
astonishing as no one supposes that they possess nerves; and by testing
Drosera with several substances which act powerfully on the nervous
system of animals, it does not appear that they include any diffused
matter analogous to nerve-tissue.

Although the cells of Drosera and Dionaea are quite as sensitive to
certain stimulants as are the tissues which surround the terminations
of the nerves in the higher animals, yet these plants are inferior even
to animals low down in the scale, in not being affected except by
stimulants in contact with their sensitive parts. They would, however,
probably be affected by radiant heat; for warm water excites energetic
movement. When a gland of Drosera, or one of the filaments of Dionaea,
is excited, the motor impulse radiates in all directions, and is not,
as in the case of animals, directed towards special points or organs.
This holds good even in the case of Drosera when some exciting
substance has been placed at two points on the disc, and when the
tentacles all round are inflected with marvellous precision towards the
two points. The rate at which the motor impulse is transmitted, though
rapid in Dionaea, is much slower than in most or all animals. This
fact, as well as that of the motor impulse not being specially directed
to certain points, are both no doubt due to the absence of nerves.
Nevertheless we perhaps see the prefigurement of the formation of
nerves in animals in the transmission of the motor impulse being so
much more rapid down the confined space within the tentacles of Drosera
than [page 367] elsewhere, and somewhat more rapid in a longitudinal
than in a transverse direction across the disc. These plants exhibit
still more plainly their inferiority to animals in the absence of any
reflex action, except in so far as the glands of Drosera, when excited
from a distance, send back some influence which causes the contents of
the cells to become aggregated down to the bases of the tentacles. But
the greatest inferiority of all is the absence of a central organ, able
to receive impressions from all points, to transmit their effects in
any definite direction, to store them up and reproduce them.  [page
368]


                          CHAPTER XVI.

                          PINGUICULA.

Pinguicula vulgaris--Structure of leaves--Number of insects and other
objects caught-- Movement of the margins of the leaves--Uses of this
movement--Secretion, digestion, and absorption--Action of the secretion
on various animal and vegetable substances--The effects of substances
not containing soluble nitrogenous matter on the glands--Pinguicula
grandiflora--Pinguicula lusitanica, catches insects--Movement of the
leaves, secretion and digestion.

PINGUICULA VULGARIS.--This plant grows in moist places, generally on
mountains. It bears on an average eight, rather thick, oblong, light
green leaves, having scarcely any footstalk. A full-sized leaf is about
1 1/2 inch in length and 3/4 inch in breadth. The young central leaves
are deeply concave, and project upwards; the older ones towards the
outside are flat or convex, and lie close to the ground, forming a
rosette from 3 to 4 inches in diameter. The margins of the leaves are
incurved. Their upper surfaces are thickly covered with two sets of
glandular hairs, differing in the size of the glands and in the length
of their pedicels. The larger glands have a circular outline as seen
from above, and are of moderate thickness; they are divided by
radiating partitions into sixteen cells, containing light-green,
homogeneous fluid. They are supported on elongated, unicellular
pedicels (containing a nucleus with a nucleolus) which rest on slight
prominences. The small glands differ only in being formed of about half
the number of cells, containing much paler fluid, and supported on much
shorter pedicels. Near the midrib, towards the base of the leaf, the
[page 369] pedicels are multicellular, are longer than elsewhere, and
bear smaller glands. All the glands secrete a colourless fluid, which
is so viscid that I have seen a fine thread drawn out to a length of 18
inches; but the fluid in this case was secreted by a gland which had
been excited.  The edge of the leaf is translucent, and does not bear
any glands; and here the spiral vessels, proceeding from the midrib,
terminate in cells marked by a spiral line, somewhat like those within
the glands of Drosera.

The roots are short. Three plants were dug up in North Wales on June
20, and carefully washed; each bore five or six unbranched roots, the
longest of which was only 1.2 of an inch.  Two rather young plants were
examined on September 28; these had a greater number of roots, namely
eight and eighteen, all under 1 inch in length, and very little
branched.

I was led to investigate the habits of this plant by being told by Mr.
W. Marshall that on the mountains of Cumberland many insects adhere to
the leaves.

[A friend sent me on June 23 thirty-nine leaves from North Wales, which
were selected owing to objects of some kind adhering to them. Of these
leaves, thirty-two had caught 142 insects, or on an average 4.4 per
leaf, minute fragments of insects not being included.  Besides the
insects, small leaves belonging to four different kinds of plants,
those of Erica tetralix being much the commonest, and three minute
seedling plants, blown by the wind, adhered to nineteen of the leaves.
One had caught as many as ten leaves of the Erica. Seeds or fruits,
commonly of Carex and one of Juncus, besides bits of moss and other
rubbish, likewise adhered to six of the thirty-nine leaves. The same
friend, on June 27, collected nine plants bearing seventy-four leaves,
and all of these, with the exception of three young leaves, had caught
insects; thirty insects were counted on one leaf, eighteen on a second,
and sixteen on a third. Another friend examined on August 22 some
plants in Donegal, Ireland, and found insects on 70 out of 157 leaves;
fifteen of [page 370] these leaves were sent me, each having caught on
an average 2.4 insects. To nine of them, leaves (mostly of Erica
tetralix) adhered; but they had been specially selected on this latter
account. I may add that early in August my son found leaves of this
same Erica and the fruits of a Carex on the leaves of a Pinguicula in
Switzerland, probably Pinguicula alpina; some insects, but no great
number, also adhered to the leaves of this plant, which had much better
developed roots than those of Pinguicula vulgaris. In Cumberland, Mr.
Marshall, on September 3, carefully examined for me ten plants bearing
eighty leaves; and on sixty-three of these (i.e. on 79 per cent.) he
found insects, 143 in number; so that each leaf had on an average 2.27
insects. A few days later he sent me some plants with sixteen seeds or
fruits adhering to fourteen leaves. There was a seed on three leaves on
the same plant. The sixteen seeds belonged to nine different kinds,
which could not be recognised, excepting one of Ranunculus, and several
belonging to three or four distinct species of Carex. It appears that
fewer insects are caught late in the year than earlier; thus in
Cumberland from twenty to twenty-four insects were observed in the
middle of July on several leaves, whereas in the beginning of September
the average number was only 2.27. Most of the insects, in all the
foregoing cases, were Diptera, but with many minute Hymenoptera,
including some ants, a few small Coleoptera, larvae, spiders, and even
small moths.]

We thus see that numerous insects and other objects are caught by the
viscid leaves; but we have no right to infer from this fact that the
habit is beneficial to the plant, any more than in the before given
case of the Mirabilis, or of the horse-chestnut. But it will presently
be seen that dead insects and other nitrogenous bodies excite the
glands to increased secretion; and that the secretion then becomes acid
and has the power of digesting animal substances, such as albumen,
fibrin, &c. Moreover, the dissolved nitrogenous matter is absorbed by
the glands, as shown by their limpid contents being aggregated into
slowly moving granular masses of protoplasm. The same results follow
when insects are naturally captured, and as the plant lives in poor
soil and has small roots, there can be no [page 371] doubt that it
profits by its power of digesting and absorbing matter from the prey
which it habitually captures in such large numbers. It will, however,
be convenient first to describe the movements of the leaves.

Movements of the Leaves.--That such thick, large leaves as those of
Pinguicula vulgarisshould have the power of curving inwards when
excited has never even been suspected. It is necessary to select for
experiment leaves with their glands secreting freely, and which have
been prevented from capturing many insects; as old leaves, at least
those growing in a state of nature, have their margins already curled
so much inwards that they exhibit little power of movement, or move
very slowly. I will first give in detail the more important experiments
which were tried, and then make some concluding remarks.

[Experiment 1.--A young and almost upright leaf was selected, with its
two lateral edges equally and very slightly incurved. A row of small
flies was placed along one margin. When looked at next day, after 15
hrs., this margin, but not the other, was found folded inwards, like
the helix of the human ear, to the breadth of 1/10 of an inch, so as to
lie partly over the row of flies (fig. 15). The glands on which the
flies rested, as well as those on the over-lapping margin which had
been brought into contact with the flies, were all secreting
copiously.

FIG. 15.  (Pinguicula vulgaris.) Outline of leaf with left margin
inflected over a row of small flies.

Experiment 2.--A row of flies was placed on one margin of a rather old
leaf, which lay flat on the ground; and in this case the margin, after
the same interval as before, namely 15 hrs., had only just begun to
curl inwards; but so much secretion had been poured forth that the
spoon-shaped tip of the leaf was filled with it.

Experiment 3.--Fragments of a large fly were placed close to the apex
of a vigorous leaf, as well as along half one margin.  [page 372] After
4 hrs. 20 m. there was decided incurvation, which increased a little
during the afternoon, but was in the same state on the following
morning. Near the apex both margins were inwardly curved. I have never
seen a case of the apex itself being in the least curved towards the
base of the leaf. After 48 hrs. (always reckoning from the time when
the flies were placed on the leaf) the margin had everywhere begun to
unfold.

Experiment 4.--A large fragment of a fly was placed on a leaf, in a
medial line, a little beneath the apex. Both lateral margins were
perceptibly incurved in 3 hrs., and after 4 hrs. 20 m. to such a degree
that the fragment was clasped by both margins. After 24 hrs. the two
infolded edges near the apex (for the lower part of the leaf was not at
all affected) were measured and found to be .11 of an inch (2.795 mm.)
apart. The fly was now removed, and a stream of water poured over the
leaf so as to wash the surface; and after 24 hrs. the margins were .25
of an inch (6.349 mm.) apart, so that they were largely unfolded. After
an additional 24 hrs. they were completely unfolded. Another fly was
now put on the same spot to see whether this leaf, on which the first
fly had been left 24 hrs., would move again; after 10 hrs.  there was a
trace of incurvation, but this did not increase during the next 24 hrs.
A bit of meat was also placed on the margin of a leaf, which four days
previously had become strongly incurved over a fragment of a fly and
had afterwards re-expanded; but the meat did not cause even a trace of
incurvation. On the contrary, the margin became somewhat reflexed, as
if injured, and so remained for the three following days, as long as it
was observed.

Experiment 5.--A large fragment of a fly was placed halfway between the
apex and base of a leaf and halfway between the midrib and one margin.
A short space of this margin, opposite the fly, showed a trace of
incurvation after 3 hrs., and this became strongly pronounced in 7 hrs.
After 24 hrs. the infolded edge was only .16 of an inch (4.064 mm.)
from the midrib. The margin now began to unfold, though the fly was
left on the leaf; so that by the next morning (i.e. 48 hrs. from the
time when the fly was first put on) the infolded edge had almost
completely recovered its original position, being now .3 of an inch
(7.62 mm.), instead of .16 of an inch, from the midrib. A trace of
flexure was, however, still visible.

Experiment 6.--A young and concave leaf was selected with its margins
slightly and naturally incurved. Two rather large, oblong, rectangular
pieces of roast meat were placed with their ends touching the infolded
edge, and .46 of an inch (11.68 mm.) [page 373] apart from one another.
After 24 hrs. the margin was greatly and equally incurved (see fig.
16) throughout this space, and for a length of .12 or .13 of an inch
(3.048 or 3.302 mm.) above and below each bit; so that the margin had
been affected over a greater length between the two bits, owing to
their conjoint action, than beyond them. The bits of meat were too
large to be clasped by the margin, but they were tilted up, one of them
so as to stand almost vertically. After 48 hrs. the margin was almost
unfolded, and the bits had sunk down. When again examined after two
days, the margin was quite unfolded, with the exception of the
naturally inflected edge; and one of the bits of meat, the end of which
had at first touched the edge, was now .067 of an inch (1.70 mm.)
distant from it; so that this bit had been pushed thus far across the
blade of the leaf.

FIG. 16.  (Pinguicula vulgaris.) Outline of leaf, with right margin
inflected against two square bits of meat.

Experiment 7.--A bit of meat was placed close to the incurved edge of a
rather young leaf, and after it had re-expanded, the bit was left lying
.11 of an inch (2.795 mm.) from the edge.  The distance from the edge
to the midrib of the fully expanded leaf was .35 of an inch (8.89 mm.);
so that the bit had been pushed inwards and across nearly one-third of
its semi-diameter.

Experiment 8.--Cubes of sponge, soaked in a strong infusion of raw
meat, were placed in close contact with the incurved edges of two
leaves,--an older and younger one. The distance from the edges to the
midribs was carefully measured. After 1 hr. 17 m. there appeared to be
a trace of incurvation. After 2 hrs. 17 m. both leaves were plainly
inflected; the distance between the edges and midribs being now only
half what it was at first. The incurvation increased slightly during
the next 4 1/2 hrs., but remained nearly the same for the next 17 hrs.
30 m. In 35 hrs. from the time when the sponges were placed on the
leaves, the margins were a little unfolded--to a greater degree in the
younger than in the older leaf. The latter was not quite unfolded until
the third day, and now both bits of sponge were left at the distance of
.1 of an inch (2.54 mm.) from the edges; or about a quarter of the
distance between the edge and midrib. A third bit of sponge adhered to
the edge, and, as the margin unfolded, was dragged backwards, into its
original position.  [page 374]

Experiment 9.--A chain of fibres of roast meat, as thin as bristles and
moistened with saliva, were placed down one whole side, close to the
narrow, naturally incurved edge of a leaf. In 3 hrs. this side was
greatly incurved along its whole length, and after 8 hrs. formed a
cylinder, about 1/20 of an inch (1.27 mm) in diameter, quite concealing
the meat. This cylinder remained closed for 32 hrs., but after 48 hrs.
was half unfolded, and in 72 hrs. was as open as the opposite margin
where no meat had been placed. As the thin fibres of meat were
completely overlapped by the margin, they were not pushed at all
inwards, across the blade.

Experiment 10.--Six cabbage seeds, soaked for a night in water, were
placed in a row close to the narrow incurved edge of a leaf. We shall
hereafter see that these seeds yield soluble matter to the glands. In 2
hrs. 25 m. the margin was decidedly inflected; in 4 hrs. it extended
over the seeds for about half their breadth, and in 7 hrs. over
three-fourths of their breadth, forming a cylinder not quite closed
along the inner side, and about .7 of an inch (1.778 mm.) in diameter.
After 24 hrs. the inflection had not increased, perhaps had decreased.
The glands which had been brought into contact with the upper surfaces
of the seeds were now secreting freely. In 36 hrs. from the time when
the seeds were put on the leaf the margin had greatly, and after 48
hrs. had completely, re-expanded. As the seeds were no longer held by
the inflected margin, and as the secretion was beginning to fail, they
rolled some way down the marginal channel.

Experiment 11.--Fragments of glass were placed on the margins of two
fine young leaves.  After 2 hrs. 30 m. the margin of one certainly
became slightly incurved; but the inflection never increased, and
disappeared in 16 hrs. 30 m. from the time when the fragments were
first applied. With the second leaf there was a trace of incurvation in
2 hrs. 15 m., which became decided in 4 hrs. 30 m., and still more
strongly pronounced in 7 hrs., but after 19 hrs.  30 m. had plainly
decreased. The fragments excited at most a slight and doubtful increase
of the secretion; and in two other trials, no increase could be
perceived. Bits of coal-cinders, placed on a leaf, produced no effect,
either owing to their lightness or to the leaf being torpid.

Experiment 12.--We now turn to fluids. A row of drops of a strong
infusion of raw meat were placed along the margins of two leaves;
squares of sponge soaked in the same infusion being placed on the
opposite margins. My object was to ascer- [page 375] tain whether a
fluid would act as energetically as a substance yielding the same
soluble matter to the glands. No distinct difference was perceptible;
certainly none in the degree of incurvation; but the incurvation round
the bits of sponge lasted rather longer, as might perhaps have been
expected from the sponge remaining damp and supplying nitrogenous
matter for a longer time. The margins, with the drops, became plainly
incurved in 2 hrs. 17 m. The incurvation subsequently increased
somewhat, but after 24 hrs. had greatly decreased.

Experiment 13.--Drops of the same strong infusion of raw meat were
placed along the midrib of a young and rather deeply concave leaf. The
distance across the broadest part of the leaf, between the naturally
incurved edges, was .55 of an inch (13.97 mm.). In 3 hrs. 27 m. this
distance was a trace less; in 6 hrs. 27 m. it was exactly .45 of an
inch (11.43 mm.), and had therefore decreased by .1 of an inch (2.54
mm.). After only 10 hrs. 37 m. the margin began to re-expand, for the
distance from edge to edge was now a trace wider, and after 24 hrs. 20
m.  was as great, within a hair's breadth, as when the drops were first
placed on the leaf. From this experiment we learn that the motor
impulse can be transmitted to a distance of .22 of an inch (5.590 mm.)
in a transverse direction from the midrib to both margins; but it would
be safer to say .2 of an inch (5.08 mm.) as the drops spread a little
beyond the midrib. The incurvation thus caused lasted for an unusually
short time.

Experiment 14.--Three drops of a solution of one part of carbonate of
ammonia to 218 of water (2 grs. to 1 oz.) were placed on the margin of
a leaf. These excited so much secretion that in 1 h. 22 m. all three
drops ran together; but although the leaf was observed for 24 hrs.,
there was no trace of inflection. We know that a rather strong solution
of this salt, though it does not injure the leaves of Drosera,
paralyses their power of movement, and I have no doubt, from the
following case, that this holds good with Pinguicula.

Experiment 15.--A row of drops of a solution of one part of carbonate
of ammonia to 875 of water (1 gr. to 2 oz.) was placed on the margin of
a leaf. In 1 hr. there was apparently some slight incurvation, and this
was well-marked in 3 hrs. 30 m. After 24 hrs. the margin was almost
completely re-expanded.

Experiment 16.--A row of large drops of a solution of one part of
phosphate of ammonia to 4375 of water (1 gr. to 10 oz.) was placed
along the margin of a leaf. No effect was produced, and after 8 hrs.
fresh drops were added along the same margin without the least effect.
We know that a solution of this [page 376] strength acts powerfully on
Drosera, and it is just possible that the solution was too strong. I
regret that I did not try a weaker solution.

Experiment 17.--As the pressure from bits of glass causes incurvation,
I scratched the margins of two leaves for some minutes with a blunt
needle, but no effect was produced. The surface of a leaf beneath a
drop of a strong infusion of raw meat was also rubbed for 10. m.  with
the end of a bristle, so as to imitate the struggles of a captured
insect; but this part of the margin did not bend sooner than the other
parts with undisturbed drops of the infusion.]

We learn from the foregoing experiments that the margins of the leaves
curl inwards when excited by the mere pressure of objects not yielding
any soluble matter, by objects yielding such matter, and by some
fluids--namely an infusion of raw meat and a week solution of carbonate
of ammonia. A stronger solution of two grains of this salt to an ounce
of water, though exciting copious secretion, paralyses the leaf. Drops
of water and of a solution of sugar or gum did not cause any movement.
Scratching the surface of the leaf for some minutes produced no effect.
Therefore, as far as we at present know, only two causes--namely slight
continued pressure and the absorption of nitrogenous matter--excite
movement. It is only the margins of the leaf which bend, for the apex
never curves towards the base. The pedicels of the glandular hairs have
no power of movement. I observed on several occasions that the surface
of the leaf became slightly concave where bits of meat or large flies
had long lain, but this may have been due to injury from
over-stimulation.

The shortest time in which plainly marked movement was observed was 2
hrs. 17 m., and this occurred when either nitrogenous substances or
fluids were placed on the leaves; but I believe that in some cases
[page 377] there was a trace of movement in 1 hr. or 1 hr. 30 m. The
pressure from fragments of glass excites movement almost as quickly as
the absorption of nitrogenous matter, but the degree of incurvation
thus caused is much less. After a leaf has become well incurved and has
again expanded, it will not soon answer to a fresh stimulus. The margin
was affected longitudinally, upwards or downwards, for a distance of
.13 of an inch (3.302 mm.) from an excited point, but for a distance of
.46 of an inch between two excited points, and transversely for a
distance of .2 of an inch (5.08 mm.). The motor impulse is not
accompanied, as in the case of Drosera, by any influence causing
increased secretion; for when a single gland was strongly stimulated
and secreted copiously, the surrounding glands were not in the least
affected. The incurvation of the margin is independent of increased
secretion, for fragments of glass cause little or no secretion, and yet
excite movement; whereas a strong solution of carbonate of ammonia
quickly excites copious secretion, but no movement.

One of the most curious facts with respect to the movement of the
leaves is the short time during which they remain incurved, although
the exciting object is left on them. In the majority of cases there was
well-marked re-expansion within 24 hrs. from the time when even large
pieces of meat, &c., were placed on the leaves, and in all cases within
48 hrs. In one instance the margin of a leaf remained for 32 hrs.
closely inflected round thin fibres of meat; in another instance, when
a bit of sponge, soaked in a strong infusion of raw meat, had been
applied to a leaf, the margin began to unfold in 35 hrs. Fragments of
glass keep the margin incurved for a shorter time than do nitrogenous
bodies; for in the former case there was [page 378] complete
re-expansion in 16 hrs. 30 m. Nitrogenous fluids act for a shorter time
than nitrogenous substances; thus, when drops of an infusion of raw
meat were placed on the midrib of a leaf, the incurved margins began to
unfold in only 10 hrs. 37 m., and this was the quickest act of
re-expansion observed by me; but it may have been partly due to the
distance of the margins from the midrib where the drops lay.

We are naturally led to inquire what is the use of this movement which
lasts for so short a time? If very small objects, such as fibres of
meat, or moderately small objects, such as little flies or
cabbage-seeds, are placed close to the margin, they are either
completely or partially embraced by it. The glands of the overlapping
margin are thus brought into contact with such objects and pour forth
their secretion, afterwards absorbing the digested matter. But as the
incurvation lasts for so short a time, any such benefit can be of only
slight importance, yet perhaps greater than at first appears. The plant
lives in humid districts, and the insects which adhere to all parts of
the leaf are washed by every heavy shower of rain into the narrow
channel formed by the naturally incurved edges. For instance, my friend
in North Wales placed several insects on some leaves, and two days
afterwards (there having been heavy rain in the interval) found some of
them quite washed away, and many others safely tucked under the now
closely inflected margins, the glands of which all round the insects
were no doubt secreting. We can thus, also, understand how it is that
so many insects, and fragments of insects, are generally found lying
within the incurved margins of the leaves.

The incurvation of the margin, due to the presence of an exciting
object, must be serviceable in another [page 379] and probably more
important way. We have seen that when large bits of meat, or of sponge
soaked in the juice of meat, were placed on a leaf, the margin was not
able to embrace them, but, as it became incurved, pushed them very
slowly towards the middle of the leaf, to a distance from the outside
of fully .1 of an inch (2.54 mm.), that is, across between one-third
and one-fourth of the space between the edge and midrib. Any object,
such as a moderately sized insect, would thus be brought slowly into
contact with a far larger number of glands, inducing much more
secretion and absorption, than would otherwise have been the case.
That this would be highly serviceable to the plant, we may infer from
the fact that Drosera has acquired highly developed powers of movement,
merely for the sake of bringing all its glands into contact with
captured insects. So again, after a leaf of Dionaea has caught an
insect, the slow pressing together of the two lobes serves merely to
bring the glands on both sides into contact with it, causing also the
secretion charged with animal matter to spread by capillary attraction
over the whole surface. In the case of Pinguicula, as soon as an insect
has been pushed for some little distance towards the midrib, immediate
re-expansion would be beneficial, as the margins could not capture
fresh prey until they were unfolded. The service rendered by this
pushing action, as well as that from the marginal glands being brought
into contact for a short time with the upper surfaces of minute
captured insects, may perhaps account for the peculiar movements of the
leaves; otherwise, we must look at these movements as a remnant of a
more highly developed power formerly possessed by the progenitors of
the genus.

In the four British species, and, as I hear from [page 380] Prof. Dyer,
in most or all the species of the genus, the edges of the leaves are in
some degree naturally and permanently incurved. This incurvation
serves, as already shown, to prevent insects from being washed away by
the rain; but it likewise serves for another end. When a number of
glands have been powerfully excited by bits of meat, insects, or any
other stimulus, the secretion often trickles down the leaf, and is
caught by the incurved edges, instead of rolling off and being lost. As
it runs down the channel, fresh glands are able to absorb the animal
matter held in solution. Moreover, the secretion often collects in
little pools within the channel, or in the spoon-like tips of the
leaves; and I ascertained that bits of albumen, fibrin, and gluten, are
here dissolved more quickly and completely than on the surface of the
leaf, where the secretion cannot accumulate; and so it would be with
naturally caught insects. The secretion was repeatedly seen thus to
collect on the leaves of plants protected from the rain; and with
exposed plants there would be still greater need of some provision to
prevent, as far as possible, the secretion, with its dissolved animal
matter, being wholly lost.

It has already been remarked that plants growing in a state of nature
have the margins of their leaves much more strongly incurved than those
grown in pots and prevented from catching many insects. We have seen
that insects washed down by the rain from all parts of the leaf often
lodge within the margins, which are thus excited to curl farther
inwards; and we may suspect that this action, many times repeated
during the life of the plant, leads to their permanent and well-marked
incurvation. I regret that this view did not occur to me in time to
test its truth.

It may here be added, though not immediately [page 381] bearing on our
subject, that when a plant is pulled up, the leaves immediately curl
downwards so as almost to conceal the roots,--a fact which has been
noticed by many persons. I suppose that this is due to the same
tendency which causes the outer and older leaves to lie flat on the
ground. It further appears that the flower-stalks are to a certain
extent irritable, for Dr. Johnson states that they "bend backwards if
rudely handled."*

Secretion, Absorption, and Digestion.--I will first give my
observations and experiments, and then a summary of the results.

[The Effects of Objects containing Soluble Nitrogenous Matter.

(1) Flies were placed on many leaves, and excited the glands to secrete
copiously; the secretion always becoming acid, though not so before.
After a time these insects were rendered so tender that their limbs and
bodies could be separated by a mere touch, owing no doubt to the
digestion and disintegration of their muscles. The glands in contact
with a small fly continued to secrete for four days, and then became
almost dry. A narrow strip of this leaf was cut off, and the glands of
the longer and shorter hairs, which had lain in contact for the four
days with the fly, and those which had not touched it, were compared
under the microscope and presented a wonderful contrast. Those which
had been in contact were filled with brownish granular matter, the
others with homogeneous fluid. There could therefore be no doubt that
the former had absorbed matter from the fly.

(2) Small bits of roast meat, placed on a leaf, always caused much acid
secretion in the course of a few hours--in one case within 40 m. When
thin fibres of meat were laid along the margin of a leaf which stood
almost upright, the secretion ran down to the ground. Angular bits of
meat, placed in little pools of the secretion near the margin, were in
the course of

* 'English Botany,' by Sir J.E. Smith; with coloured figures by J.
Sowerby; edit. of 1832, tab.  24, 25, 26.  [page 382]

two or three days much reduced in size, rounded, rendered more or less
colourless and transparent, and so much softened that they fell to
pieces on the slightest touch. In only one instance was a very minute
particle completely dissolved, and this occurred within 48 hrs.  When
only a small amount of secretion was excited, this was generally
absorbed in from 24 hrs. to 48 hrs.; the glands being left dry. But
when the supply of secretion was copious, round either a single rather
large bit of meat, or round several small bits, the glands did not
become dry until six or seven days had elapsed. The most rapid case of
absorption observed by me was when a small drop of an infusion of raw
meat was placed on a leaf, for the glands here became almost dry in 3
hrs. 20 m. Glands excited by small particles of meat, and which have
quickly absorbed their own secretion, begin to secrete again in the
course of seven or eight days from the time when the meat was given
them.

(3) Three minute cubes of tough cartilage from the leg-bone of a sheep
were laid on a leaf.  After 10 hrs. 30 m. some acid secretion was
excited, but the cartilage appeared little or not at all affected.
After 24 hrs. the cubes were rounded and much reduced in size; after 32
hrs.  they were softened to the centre, and one was quite liquefied;
after 35 hrs. mere traces of solid cartilage were left; and after 48
hrs. a trace could still be seen through a lens in only one of the
three. After 82 hrs. not only were all three cubes completely
liquefied, but all the secretion was absorbed and the glands left dry.

(4) Small cubes of albumen were placed on a leaf; in 8 hrs. feebly acid
secretion extended to a distance of nearly 1/10 of an inch round them,
and the angles of one cube were rounded.  After 24 hrs. the angles of
all the cubes were rounded, and they were rendered throughout very
tender; after 30 hrs. the secretion began to decrease, and after 48
hrs. the glands were left dry; but very minute bits of albumen were
still left undissolved.

(5) Smaller cubes of albumen (about 1/50 or 1/60 of an inch, .508 or
.423 mm.) were placed on four glands; after 18 hrs. one cube was
completely dissolved, the others being much reduced in size, softened,
and transparent. After 24 hrs. two of the cubes were completely
dissolved, and already the secretion on these glands was almost wholly
absorbed. After 42 hrs. the two other cubes were completely dissolved.
These four glands began to secrete again after eight or nine days.

(6) Two large cubes of albumen (fully 1/20 of an inch, 1.27 mm.) were
placed, one near the midrib and the other near the margin [page 383] of
a leaf; in 6 hrs. there was much secretion, which after 48 hrs.
accumulated in a little pool round the cube near the margin. This cube
was much more dissolved than that on the blade of the leaf; so that
after three days it was greatly reduced in size, with all the angles
rounded, but it was too large to be wholly dissolved. The secretion was
partially absorbed after four days. The cube on the blade was much less
reduced, and the glands on which it rested began to dry after only two
days.

(7) Fibrin excites less secretion than does meat or albumen. Several
trials were made, but I will give only three of them. Two minute shreds
were placed on some glands, and in 3 hrs. 45 m. their secretion was
plainly increased. The smaller shred of the two was completely
liquefied in 6 hrs. 15 m., and the other in 24 hrs.; but even after 48
hrs. a few granules of fibrin could still be seen through a lens
floating in both drops of secretion. After 56 hrs. 30 m. these granules
were completely dissolved. A third shred was placed in a little pool of
secretion, within the margin of a leaf where a seed had been lying, and
this was completely dissolved in the course of 15 hrs. 30 m.

(8) Five very small bits of gluten were placed on a leaf, and they
excited so much secretion that one of the bits glided down into the
marginal furrow. After a day all five bits seemed much reduced in size,
but none were wholly dissolved. On the third day I pushed two of them,
which had begun to dry, on to fresh glands. On the fourth day
undissolved traces of three out of the five bits could still be
detected, the other two having quite disappeared; but I am doubtful
whether they had really been completely dissolved. Two fresh bits were
now placed, one near the middle and the other near the margin of
another leaf; both excited an extraordinary amount of secretion; that
near the margin had a little pool formed round it, and was much more
reduced in size than that on the blade, but after four days was not
completely dissolved. Gluten, therefore, excites the glands greatly,
but is dissolved with much difficulty, exactly as in the case of
Drosera. I regret that I did not try this substance after having been
immersed in weak hydrochloric acid, as it would then probably have been
quickly dissolved.

(9) A small square thin piece of pure gelatine, moistened with water,
was placed on a leaf, and excited very little secretion in 5 hrs. 30
m., but later in the day a greater amount. After 24 hrs. the whole
square was completely liquefied; and this would not have occurred had
it been left in water. The liquid was acid.

(10) Small particles of chemically prepared casein excited [page 384]
acid secretion, but were not quite dissolved after two days; and the
glands then began to dry.  Nor could their complete dissolution have
been expected from what we have seen with Drosera.

(11) Minute drops of skimmed milk were placed on a leaf, and these
caused the glands to secrete freely. After 3 hrs. the milk was found
curdled, and after 23 hrs. the curds were dissolved. On placing the now
clear drops under the microscope, nothing could be detected except some
oil-globules. The secretion, therefore, dissolves fresh casein.

(12) Two fragments of a leaf were immersed for 17 hrs., each in a
drachm of a solution of carbonate of ammonia, of two strengths, namely
of one part to 437 and 218 of water. The glands of the longer and
shorter hairs were then examined, and their contents found aggregated
into granular matter of a brownish-green colour. These granular masses
were seen by my son slowly to change their forms, and no doubt
consisted of protoplasm. The aggregation was more strongly pronounced,
and the movements of the protoplasm more rapid, within the glands
subjected to the stronger solution than in the others. The experiment
was repeated with the same result; and on this occasion I observed that
the protoplasm had shrunk a little from the walls of the single
elongated cells forming the pedicels. In order to observe the process
of aggregation, a narrow strip of leaf was laid edgeways under the
microscope, and the glands were seen to be quite transparent; a little
of the stronger solution (viz. one part to 218 of water) was now added
under the covering glass; after an hour or two the glands contained
very fine granular matter, which slowly became coarsely granular and
slightly opaque; but even after 5 hrs. not as yet of a brownish tint.
By this time a few rather large, transparent, globular masses appeared
within the upper ends of the pedicels, and the protoplasm lining their
walls had shrunk a little. It is thus evident that the glands of
Pinguicula absorb carbonate of ammonia; but they do not absorb it, or
are not acted on by it, nearly so quickly as those of Drosera.

(13) Little masses of the orange-coloured pollen of the common pea,
placed on several leaves, excited the glands to secrete freely. Even a
very few grains which accidentally fell on a single gland caused the
drop surrounding it to increase so much in size, in 23 hrs., as to be
manifestly larger than the drops on the adjoining glands. Grains
subjected to the secretion for 48 hrs. did not emit their tubes; they
were quite discoloured, and seemed to contain less matter than before;
that [page 385] which was left being of a dirty colour, including
globules of oil. They thus differed in appearance from other grains
kept in water for the same length of time. The glands in contact with
the pollen-grains had evidently absorbed matter from them; for they had
lost their natural pale-green tint, and contained aggregated globular
masses of protoplasm.

(14) Square bits of the leaves of spinach, cabbage, and a saxifrage,
and the entire leaves of Erica tetralix, all excited the glands to
increased secretion. The spinach was the most effective, for it caused
the secretion evidently to increase in 1 hr. 40 m., and ultimately to
run some way down the leaf; but the glands soon began to dry, viz.
after 35 hrs. The leaves of Erica tetralix began to act in 7 hrs. 30
m., but never caused much secretion; nor did the bits of leaf of the
saxifrage, though in this case the glands continued to secrete for
seven days.  Some leaves of Pinguicula were sent me from North Wales,
to which leaves of Erica tetralixand of an unknown plant adhered; and
the glands in contact with them had their contents plainly aggregated,
as if they had been in contact with insects; whilst the other glands on
the same leaves contained only clear homogeneous fluid.

(15) Seeds.--A considerable number of seeds or fruits selected by
hazard, some fresh and some a year old, some soaked for a short time in
water and some not soaked, were tried. The ten following kinds, namely
cabbage, radish, Anemone nemorosa, Rumex acetosa, Carex sylvatica,
mustard, turnip, cress, Ranunculus acris, and Avena pubescens, all
excited much secretion, which was in several cases tested and found
always acid. The five first-named seeds excited the glands more than
the others. The secretion was seldom copious until about 24 hrs. had
elapsed, no doubt owing to the coats of the seeds not being easily
permeable.  Nevertheless, cabbage seeds excited some secretion in 4
hrs. 30 m.; and this increased so much in 18 hrs. as to run down the
leaves. The seeds or properly the fruits of Carex are much oftener
found adhering to leaves in a state of nature than those of any other
genus; and the fruits of Carex sylvatica excited so much secretion that
in 15 hrs. it ran into the incurved edges; but the glands ceased to
secrete after 40 hrs. On the other hand, the glands on which the seeds
of the Rumex and Avena rested continued to secrete for nine days.

The nine following kinds of seeds excited only a slight amount of
secretion, namely, celery, parsnip, caraway, Linum grandiflorum,
Cassia, Trifolium pannonicum, Plantago, onion, [page 386] and Bromus.
Most of these seeds did not excite any secretion until 48 hrs. had
elapsed, and in the case of the Trifolium only one seed acted, and this
not until the third day. Although the seeds of the Plantago excited
very little secretion, the glands continued to secrete for six days.
Lastly, the five following kinds excited no secretion, though left on
the leaves for two or three days, namely lettuce, Erica tetralix,
Atriplex hortensis, Phalaris canariensis, and wheat. Nevertheless, when
the seeds of the lettuce, wheat, and Atriplex were split open and
applied to leaves, secretion was excited in considerable quantity in 10
hrs., and I believe that some was excited in six hours. In the case of
the Atriplex the secretion ran down to the margin, and after 24 hrs. I
speak of it in my notes "as immense in quantity and acid." The split
seeds also of the Trifolium and celery acted powerfully and quickly,
though the whole seeds caused, as we have seen, very little secretion,
and only after a long interval of time. A slice of the common pea,
which however was not tried whole, caused secretion in 2 hrs.  From
these facts we may conclude that the great difference in the degree and
rate at which various kinds of seeds excite secretion, is chiefly or
wholly due to the different permeability of their coats.

Some thin slices of the common pea, which had been previously soaked
for 1 hr. in water, were placed on a leaf, and quickly excited much
acid secretion. After 24 hrs. these slices were compared under a high
power with others left in water for the same time; the latter contained
so many fine granules of legumin that the slide was rendered muddy;
whereas the slices which had been subjected to the secretion were much
cleaner and more transparent, the granules of legumin apparently having
been dissolved. A cabbage seed which had lain for two days on a leaf
and had excited much acid secretion, was cut into slices, and these
were compared with those of a seed which had been left for the same
time in water. Those subjected to the secretion were of a paler colour;
their coats presenting the greatest differences, for they were of a
pale dirty tint instead of chestnut-brown. The glands on which the
cabbage seeds had rested, as well as those bathed by the surrounding
secretion, differed greatly in appearance from the other glands on the
same leaf, for they all contained brownish granular matter, proving
that they had absorbed matter from the seeds.

That the secretion acts on the seeds was also shown by some of them
being killed, or by the seedlings being injured. Fourteen cabbage seeds
were left for three days on leaves and excited [page 387] much
secretion; they were then placed on damp sand under conditions known to
be favourable for germination. Three never germinated, and this was a
far larger proportion of deaths than occurred with seeds of the same
lot, which had not been subjected to the secretion, but were otherwise
treated in the same manner. Of the eleven seedlings raised, three had
the edges of their cotyledons slightly browned, as if scorched; and the
cotyledons of one grew into a curious indented shape. Two mustard seeds
germinated; but their cotyledons were marked with brown patches and
their radicles deformed. Of two radish seeds, neither germinated;
whereas of many seeds of the same lot not subjected to the secretion,
all, excepting one, germinated. Of the two Rumex seeds, one died and
the other germinated; but its radicle was brown and soon withered. Both
seeds of the Avena germinated, one grew well, the other had its radicle
brown and withered. Of six seeds of the Erica none germinated, and when
cut open after having been left for five months on damp sand, one alone
seemed alive. Twenty-two seeds of various kinds were found adhering to
the leaves of plants growing in a state of nature; and of these, though
kept for five months on damp sand, none germinated, some being then
evidently dead.

The Effects of Objects not containing Soluble Nitrogenous Matter.

(16) It has already been shown that bits of glass, placed on leaves,
excite little or no secretion. The small amount which lay beneath the
fragments was tested and found not acid.  A bit of wood excited no
secretion; nor did the several kinds of seeds of which the coats are
not permeable to the secretion, and which, therefore, acted like
inorganic bodies. Cubes of fat, left for two days on a leaf, produced
no effect.

(17) A particle of white sugar, placed on a leaf, formed in 1 hr. 10 m.
a large drop of fluid, which in the course of 2 additional hours ran
down into the naturally inflected margin. This fluid was not in the
least acid, and began to dry up, or more probably was absorbed, in 5
hrs.  30 m. The experiment was repeated; particles being placed on a
leaf, and others of the same size on a slip of glass in a moistened
state; both being covered by a bell-glass. This was done to see whether
the increased amount of fluid on the leaves could be due to mere
deliquescence; but this was proved not to be the case. The particle on
the leaf caused so much secretion that in the course of 4 hrs. it ran
down across two-thirds of the leaf. After 8 hrs. the leaf, which was
concave, was actually filled with very viscid [page 388] fluid; and it
particularly deserves notice that this, as on the former occasion, was
not in the least acid. This great amount of secretion may be attributed
to exosmose. The glands which had been covered for 24 hrs. by this
fluid did not differ, when examined under the microscope, from others
on the same leaf, which had not come into contact with it. This is an
interesting fact in contrast with the invariably aggregated condition
of glands which have been bathed by the secretion, when holding animal
matter in solution.

(18) Two particles of gum arabic were placed on a leaf, and they
certainly caused in 1 hr. 20 m. a slight increase of secretion. This
continued to increase for the next 5 hrs., that is for as long a time
as the leaf was observed.

(19) Six small particles of dry starch of commerce were placed on a
leaf, and one of these caused some secretion in 1 hr. 15 m., and the
others in from 8 hrs. to 9 hrs. The glands which had thus been excited
to secrete soon became dry, and did not begin to secrete again until
the sixth day. A larger bit of starch was then placed on a leaf, and no
secretion was excited in 5 hrs. 30 m.; but after 8 hrs. there was a
considerable supply, which increased so much in 24 hrs. as to run down
the leaf to the distance of 3/4 of an inch. This secretion, though so
abundant, was not in the least acid. As it was so copiously excited,
and as seeds not rarely adhere to the leaves of naturally growing
plants, it occurred to me that the glands might perhaps have the power
of secreting a ferment, like ptyaline, capable of dissolving starch; so
I carefully observed the above six small particles during several days,
but they did not seem in the least reduced in bulk. A particle was also
left for two days in a little pool of secretion, which had run down
from a piece of spinach leaf; but although the particle was so minute
no diminution was perceptible. We may therefore conclude that the
secretion cannot dissolve starch. The increase caused by this substance
may, I presume, be attributed to exosmose. But I am surprised that
starch acted so quickly and powerfully as it did, though in a less
degree than sugar. Colloids are known to possess some slight power of
dialysis; and on placing the leaves of a Primula in water, and others
in syrup and diffused starch, those in the starch became flaccid, but
to a less degree and at a much slower rate than the leaves in the
syrup; those in water remaining all the time crisp.]

From the foregoing experiments and observations we [page 389] see that
objects not containing soluble matter have little or no power of
exciting the glands to secrete. Non-nitrogenous fluids, if dense, cause
the glands to pour forth a large supply of viscid fluid, but this is
not in the least acid. On the other hand, the secretion from glands
excited by contact with nitrogenous solids or liquids is invariably
acid, and is so copious that it often runs down the leaves and collects
within the naturally incurved margins. The secretion in this state has
the power of quickly dissolving, that is of digesting, the muscles of
insects, meat, cartilage, albumen, fibrin, gelatine, and casein as it
exists in the curds of milk.  The glands are strongly excited by
chemically prepared casein and gluten; but these substances (the latter
not having been soaked in weak hydrochloric acid) are only partially
dissolved, as was likewise the case with Drosera. The secretion, when
containing animal matter in solution, whether derived from solids or
from liquids, such as an infusion of raw meat, milk, or a weak solution
of carbonate of ammonia, is quickly absorbed; and the glands, which
were before limpid and of a greenish colour, become brownish and
contain masses of aggregated granular matter. This matter, from its
spontaneous movements, no doubt consists of protoplasm. No such effect
is produced by the action of non-nitrogenous fluids. After the glands
have been excited to secrete freely, they cease for a time to secrete,
but begin again in the course of a few days.

Glands in contact with pollen, the leaves of other plants, and various
kinds of seeds, pour forth much acid secretion, and afterwards absorb
matter probably of an albuminous nature from them. Nor can the benefit
thus derived be insignificant, for a considerable [page 390] amount of
pollen must be blown from the many wind-fertilised carices, grasses,
&c., growing where Pinguicula lives, on to the leaves thickly covered
with viscid glands and forming large rosettes. Even a few grains of
pollen on a single gland causes it to secrete copiously. We have also
seen how frequently the small leaves of Erica tetralix and of other
plants, as well as various kinds of seeds and fruits, especially of
Carex, adhere to the leaves. One leaf of the Pinguicula had caught ten
of the little leaves of the Erica; and three leaves on the same plant
had each caught a seed. Seeds subjected to the action of the secretion
are sometimes killed, or the seedlings injured. We may, therefore,
conclude that Pinguicula vulgaris, with its small roots, is not only
supported to a large extent by the extraordinary number of insects
which it habitually captures, but likewise draws some nourishment from
the pollen, leaves, and seeds of other plants which often adhere to its
leaves. It is therefore partly a vegetable as well as an animal
feeder.

                    PINGUICULA GRANDIFLORA.

This species is so closely allied to the last that it is ranked by Dr.
Hooker as a sub-species. It differs chiefly in the larger size of its
leaves, and in the glandular hairs near the basal part of the midrib
being longer. But it likewise differs in constitution; I hear from Mr.
Ralfs, who was so kind as to send me plants from Cornwall, that it
grows in rather different sites; and Dr. Moore, of the Glasnevin
Botanic Gardens, informs me that it is much more manageable under
culture, growing freely and flowering annually; whilst Pinguicula
vulgaris has to be renewed every year. Mr. Ralfs found numerous [page
391] insects and fragments of insects adhering to almost all the
leaves. These consisted chiefly of Diptera, with some Hymenoptera,
Homoptera, Coleoptera, and a moth. On one leaf there were nine dead
insects, besides a few still alive. He also observed a few fruits of
Carex pulicaris, as well as the seeds of this same Pinguicula, adhering
to the leaves. I tried only two experiments with this species; firstly,
a fly was placed near the margin of a leaf, and after 16 hrs. this was
found well inflected. Secondly, several small flies were placed in a
row along one margin of another leaf, and by the next morning this
whole margin was curled inwards, exactly as in the case of Pinguicula
vulgaris.

                    PINGUICULA LUSITANICA.

This species, of which living specimens were sent me by Mr. Ralfs from
Cornwall, is very distinct from the two foregoing ones. The leaves are
rather smaller, much more transparent, and are marked with purple
branching veins. The margins of the leaves are much more involuted;
those of the older ones extending over a third of the space between the
midrib and the outside. As in the two other species, the glandular
hairs consist of longer and shorter ones, and have the same structure;
but the glands differ in being purple, and in often containing granular
matter before they have been excited. In the lower part of the leaf,
almost half the space on each side between the midrib and margin is
destitute of glands; these being replaced by long, rather stiff,
multicellular hairs, which intercross over the midrib. These hairs
perhaps serve to prevent insects from settling on this part of the
leaf, where there are no viscid glands by which they could be caught;
but it is hardly probable that they were developed for this purpose.
The spiral vessels pro- [page 392] ceeding from the midrib terminate at
the extreme margin of the leaf in spiral cells; but these are not so
well developed as in the two preceding species. The flower-peduncles,
sepals, and petals, are studded with glandular hairs, like those on the
leaves.

The leaves catch many small insects, which are found chiefly beneath
the involuted margins, probably washed there by the rain. The colour of
the glands on which insects have long lain is changed, being either
brownish or pale purple, with their contents coarsely granular; so that
they evidently absorb matter from their prey. Leaves of the Erica
tetralix, flowers of a Galium, scales of grasses, &c. likewise adhered
to some of the leaves. Several of the experiments which were tried on
Pinguicula vulgaris were repeated on Pinguicula lusitanica, and these
will now be given.

[(1) A moderately sized and angular bit of albumen was placed on one
side of a leaf, halfway between the midrib and the naturally involuted
margin. In 2 hrs. 15 m. the glands poured forth much secretion, and
this side became more infolded than the opposite one. The inflection
increased, and in 3 hrs. 30 m. extended up almost to the apex. After 24
hrs. the margin was rolled into a cylinder, the outer surface of which
touched the blade of the leaf and reached to within the 1/20 of an inch
of the midrib. After 48 hrs. it began to unfold, and in 72 hrs. was
completely unfolded. The cube was rounded and greatly reduced in size;
the remainder being in a semi-liquefied state.

(2) A moderately sized bit of albumen was placed near the apex of a
leaf, under the naturally incurved margin. In 2 hrs. 30 m. much
secretion was excited, and next morning the margin on this side was
more incurved than the opposite one, but not to so great a degree as in
the last case. The margin unfolded at the same rate as before. A large
proportion of the albumen was dissolved, a remnant being still left.

(3) Large bits of albumen were laid in a row on the midribs of two
leaves, but produced in the course of 24 hrs. no effect; [page 393] nor
could this have been expected, for even had glands existed here, the
long bristles would have prevented the albumen from coming in contact
with them. On both leaves the bits were now pushed close to one margin,
and in 3 hrs. 30 m. this became so greatly inflected that the outer
surface touched the blade; the opposite margin not being in the least
affected. After three days the margins of both leaves with the albumen
were still as much inflected as ever, and the glands were still
secreting copiously. With Pinguicula vulgaris I have never seen
inflection lasting so long.

(4) Two cabbage seeds, after being soaked for an hour in water, were
placed near the margin of a leaf, and caused in 3 hrs. 20 m. increased
secretion and incurvation. After 24 hrs. the leaf was partially
unfolded, but the glands were still secreting freely. These began to
dry in 48 hrs., and after 72 hrs. were almost dry. The two seeds were
then placed on damp sand under favourable conditions for growth; but
they never germinated, and after a time were found rotten. They had no
doubt been killed by the secretion.

(5) Small bits of a spinach leaf caused in 1 hr. 20 m. increased
secretion; and after 3 hrs. 20 m. plain incurvation of the margin. The
margin was well inflected after 9 hrs. 15 m., but after 24 hrs. was
almost fully re-expanded. The glands in contact with the spinach became
dry in 72 hrs. Bits of albumen had been placed the day before on the
opposite margin of this same leaf, as well as on that of a leaf with
cabbage seeds, and these margins remained closely inflected for 72
hrs., showing how much more enduring is the effect of albumen than of
spinach leaves or cabbage seeds .

(6) A row of small fragments of glass was laid along one margin of a
leaf; no effect was produced in 2 hrs. 10 m., but after 3 hrs. 25 m.
there seemed to be a trace of inflection, and this was distinct, though
not strongly marked, after 6 hrs. The glands in contact with the
fragments now secreted more freely than before; so that they appear to
be more easily excited by the pressure of inorganic objects than are
the glands of Pinguicula vulgaris. The above slight inflection of the
margin had not increased after 24 hrs., and the glands were now
beginning to dry. The surface of a leaf, near the midrib and towards
the base, was rubbed and scratched for some time, but no movement
ensued. The long hairs which are situated here were treated in the same
manner, with no effect. This latter trial was made because I thought
that the hairs might perhaps be sensitive to a touch, like the
filaments of Dionaea.  [page 394]

(7) The flower-peduncles, sepals and petals, bear glands in general
appearance like those on the leaves. A piece of a flower-peduncle was
therefore left for 1 hr. in a solution of one part of carbonate of
ammonia to 437 of water, and this caused the glands to change from
bright pink to a dull purple colour; but their contents exhibited no
distinct aggregation. After 8 hrs.  30 m. they became colourless. Two
minute cubes of albumen were placed on the glands of a flower-peduncle,
and another cube on the glands of a sepal; but they were not excited to
increased secretion, and the albumen after two days was not in the
least softened. Hence these glands apparently differ greatly in
function from those on the leaves.]

From the foregoing observations on Pinguicula lusitanica we see that
the naturally much incurved margins of the leaves are excited to curve
still farther inwards by contact with organic and inorganic bodies;
that albumen, cabbage seeds, bits of spinach leaves, and fragments of
glass, cause the glands to secrete more freely;--that albumen is
dissolved by the secretion, and cabbage seeds killed by it;--and lastly
that matter is absorbed by the glands from the insects which are caught
in large numbers by the viscid secretion. The glands on the
flower-peduncles seem to have no such power. This species differs from
Pinguicula vulgarisand grandiflora in the margins of the leaves, when
excited by organic bodies, being inflected to a greater degree, and in
the inflection lasting for a longer time. The glands, also, seem to be
more easily excited to increased secretion by bodies not yielding
soluble nitrogenous matter. In other respects, as far as my
observations serve, all three species agree in their functional
powers.  [page 395]



                         CHAPTER XVII.

                          UTRICULARIA.

Utricularia neglecta--Structure of the bladder--The uses of the several
parts--Number of imprisoned animals--Manner of capture--The bladders
cannot digest animal matter, but absorb the products of its
decay--Experiments on the absorption of certain fluids by the quadrifid
processes--Absorption by the glands--Summary of the observation on
absorption-- Development of the bladders--Utricularia
vulgaris--Utricularia minor--Utricularia clandestina.

I WAS led to investigate the habits and structure of the species of
this genus partly from their belonging to the same natural family as
Pinguicula, but more especially by Mr. Holland's statement, that "water
insects are often found imprisoned in the bladders," which he suspects
"are destined for the plant to feed on."* The plants which I first
received as Utricularia vulgaris from the New Forest in Hampshire and
from Cornwall, and which I have chiefly worked on, have been determined
by Dr. Hooker to be a very rare British species, the Utricularia
neglecta of Lehm.  I subsequently received the true Utricularia
vulgaris from Yorkshire. Since drawing up the following description
from my own observations and those of my son, Francis Darwin, an
important memoir by Prof. Cohn

*The 'Quart. Mag. of the High Wycombe Nat. Hist. Soc.' July 1868, p. 5.
Delpino ('Ult.  Osservaz. sulla Dicogamia,' &c. 1868-1869, p. 16) also
quotes Crouan as having found (1858) crustaceans within the bladders of
Utricularia vulgaris.

  I am much indebted to the Rev. H.M. Wilkinson, of Bistern, for having
  sent me several fine lots of this species from the New Forest. Mr.
Ralfs was also so kind as to send me living plants of the same species
from near Penzance in Cornwall.  [page 396]

on Utricularia vulgaris has appeared;* and it has been no small
satisfaction to me to find that my account agrees almost completely
with that of this distinguished observer. I will publish my description
as it stood before reading that by Prof. Cohn, adding occasionally some
statements on his authority.

FIG. 17.  (Utricularia neglecta.) Branch with the divided leaves
bearing bladders; about twice enlarged.

Utricularia neglecta.--The general appearance of a branch (about twice
enlarged), with the pinnatifid leaves bearing bladders, is represented
in the above sketch (fig. 17). The leaves continually bifurcate, so
that a full-grown one terminates in from twenty to thirty

* 'Beitrage zur Biologie der Plflanzen' drittes Heft, 1875.  [page 397]

points. Each point is tipped by a short, straight bristle; and slight
notches on the sides of the leaves bear similar bristles. On both
surfaces there are many small papillae, crowned with two hemispherical
cells in close contact. The plants float near the surface of the water,
and are quite destitute of roots, even during the earliest period of
growth.* They commonly inhabit, as more than one observer has remarked
to me, remarkably foul ditches.

The bladders offer the chief point of interest. There are often two or
three on the same divided leaf, generally near the base; though I have
seen a single one growing from the stem.  They are supported on short
footstalks. When fully grown, they are nearly 1/10 of an inch (2.54
mm.) in length. They are translucent, of a green colour, and the walls
are formed of two layers of cells. The exterior cells are polygonal and
rather large; but at many of the points where the angles meet, there
are smaller rounded cells. These latter support short conical
projections, surmounted by two hemispherical cells in such close
apposition that they appear united; but they often separate a little
when immersed in certain fluids. The papillae thus formed are exactly
like those on the surfaces of the leaves. Those on the same bladder
vary much in size; and there are a few, especially on very young
bladders, which have an elliptical instead of a circular outline. The
two terminal cells are transparent, but must hold much matter in
solution, judging from the quantity coagulated by prolonged immersion
in alcohol or ether.

* I infer that this is the case from a drawing of a seedling given by
Dr. Warming in his paper, "Bidrag til Kundskaben om Lentibulariaceae,"
from the 'Videnskabelige Meddelelser,' Copenhagen, 1874, Nos. 3-7, pp.
33-58.) [page 398]

The bladders are filled with water. They generally, but by no means
always, contain bubbles of air. According to the quantity of the
contained water and air, they vary much in thickness, but are always
somewhat compressed. At an early stage of growth, the flat or ventral
surface faces the axis or stem; but the footstalks must have some power
of movement; for in plants kept in my greenhouse the ventral surface
was generally turned either straight or obliquely downwards. The Rev.
H.M. Wilkinson examined

FIG. 18.  (Utricularia neglecta.) Bladder; much enlarged. c, collar
indistinctly seen through the walls.

plants for me in a state of nature, and found this commonly to be the
case, but the younger bladders often had their valves turned upwards.

The general appearance of a bladder viewed laterally, with the
appendages on the near side alone represented, is shown in the
accompanying figure (fig. 18). The lower side, where the footstalk
arises, is nearly straight, and I have called it the ventral surface.
The other or dorsal surface is convex, and terminates in two long
prolongations, formed of several rows of cells, containing chlorophyll,
and bearing, chiefly on [page 399] the outside, six or seven long,
pointed, multicellular bristles. These prolongations of the bladder may
be conveniently called the antennae, for the whole bladder (see fig.
17) curiously resembles an entomostracan crustacean, the short
footstalk representing the tail. In fig. 18, the near antenna alone is
shown. Beneath the two antennae the end of the bladder is slightly
truncated, and here is situated the most important part of the whole
structure, namely the entrance and valve. On each side of the entrance
from three to rarely seven long, multicellular bristles project out-

FIG. 19.  (Utricularia neglecta.) Valve of bladder; greatly enlarged.

wards; but only those (four in number) on the near side are shown in
the drawing. These bristles, together with those borne by the antennae,
form a sort of hollow cone surrounding the entrance.

The valve slopes into the cavity of the bladder, or upwards in fig. 18.
It is attached on all sides to the bladder, excepting by its posterior
margin, or the lower one in fig. 19, which is free, and forms one side
of the slit-like orifice leading into the bladder. This margin is
sharp, thin, and smooth, and rests on the edge of a rim or collar,
which dips deeply into the [page 400] bladder, as shown in the
longitudinal section (fig. 20) of the collar and valve; it is also
shown at c, in fig. 18. The edge of the valve can thus open only
inwards. As both the valve and collar dip into the bladder, a hollow or
depression is here formed, at the base of which lies the slit-like
orifice.

The valve is colourless, highly transparent, flexible and elastic. It
is convex in a transverse direction, but has been drawn (fig. 19) in a
flattened state, by which its apparent breadth is increased. It is
formed,

FIG. 20.  (Utricularia neglecta.) Longitudinal vertical section through
the ventral portion of a bladder; showing valve and collar. v, valve;
the whole projection above c forms the collar; b, bifid processes; s,
ventral surface of bladder.

according to Cohn, of two layers of small cells, which are continuous
with the two layers of larger cells forming the walls of the bladder,
of which it is evidently a prolongation. Two pairs of transparent
pointed bristles, about as long as the valve itself, arise from near
the free posterior margin (fig. 18), and point obliquely outwards in
the direction of the antennae.  There are also on the surface of the
valve numerous glands, as I will call them; for they have the power of
absorption, though I doubt whether they ever secrete. They consist of
three kinds, which [page 401] to a certain extent graduate into one
another. Those situated round the anterior margin of the valve (upper
margin in fig. 19) are very numerous and crowded together; they consist
of an oblong head on a long pedicel. The pedicel itself is formed of an
elongated cell, surmounted by a short one. The glands towards the free
posterior margin are much larger, few in number, and almost spherical,
having short footstalks; the head is formed by the confluence of two
cells, the lower one answering to the short upper cell of the pedicel
of the oblong glands. The glands of the third kind have transversely
elongated heads, and are seated on very short footstalks; so that they
stand parallel and close to the surface of the valve; they may be
called the two-armed glands. The cells forming all these glands contain
a nucleus, and are lined by a thin layer of more or less granular
protoplasm, the primordial utricle of Mohl. They are filled with fluid,
which must hold much matter in solution, judging from the quantity
coagulated after they have been long immersed in alcohol or ether. The
depression in which the valve lies is also lined with innumerable
glands; those at the sides having oblong heads and elongated pedicels,
exactly like the glands on the adjoining parts of the valve.

The collar (called the peristome by Cohn) is evidently formed, like the
valve, by an inward projection of the walls of the bladder. The cells
composing the outer surface, or that facing the valve, have rather
thick walls, are of a brownish colour, minute, very numerous, and
elongated; the lower ones being divided into two by vertical
partitions. The whole presents a complex and elegant appearance. The
cells forming the inner surface are continuous with those over the
whole inner surface of the bladder. The space be- [page 402] tween the
inner and outer surface consists of coarse cellular tissue (fig. 20).
The inner side is thickly covered with delicate bifid processes,
hereafter to be described. The collar is thus made thick; and it is
rigid, so that it retains the same outline whether the bladder contains
little or much air and water. This is of great importance, as otherwise
the thin and flexible valve would be liable to be distorted, and in
this case would not act properly.

Altogether the entrance into the bladder, formed by the transparent
valve, with its four obliquely projecting bristles, its numerous
diversely shaped glands, surrounded by the collar, bearing glands on
the inside and bristles on the outside, together with the bristles
borne by the antennae, presents an extraordinarily complex appearance
when viewed under the microscope.

We will now consider the internal structure of the bladder. The whole
inner surface, with the exception of the valve, is seen under a
moderately high power to be covered with a serried mass of processes
(fig. 21). Each of these consists of four divergent arms; whence their
name of quadrifid processes. They arise from small angular cells, at
the junctions of the angles of the larger cells which form the interior
of the bladder. The middle part of the upper surface of these small
cells projects a little, and then contracts into a very short and
narrow footstalk which bears the four arms (fig. 22.). Of these, two
are long, but often of not quite equal length, and project obliquely
inwards and towards the posterior end of the bladder. The two others
are much shorter, and project at a smaller angle, that is, are more
nearly horizontal, and are directed towards the anterior end of the
bladder. These arms are only moderately sharp; they are composed of ex-
[page 403] tremely thin transparent membrane, so that they can be bent
or doubled in any direction without being broken. They are lined with a
delicate layer of protoplasm, as is likewise the short conical
projection from which they arise. Each arm generally (but not
invariably) contains a minute, faintly brown particle, either rounded
or more commonly elongated, which exhibits incessant Brownian
movements. These par-

FIG. 21.  (Utricularia neglecta.) Small portion of inside of bladder,
much enlarged, showing quadrifid processes.

FIG. 22.  (Utricularia neglecta.) One of the quadrifid processes
greatly enlarged.

ticles slowly change their positions, and travel from one end to the
other of the arms, but are commonly found near their bases. They are
present in the quadrifids of young bladders, when only about a third of
their full size. They do not resemble ordinary nuclei, but I believe
that they are nuclei in a modified condition, for when absent, I could
occasionally just distinguish in their places a delicate halo of
matter, including a darker spot. Moreover, the quadrifids of
Utricularia montana contain rather larger and much [page 404] more
regularly spherical, but otherwise similar, particles, which closely
resemble the nuclei in the cells forming the walls of the bladders. In
the present case there were sometimes two, three, or even more, nearly
similar particles within a single arm; but, as we shall hereafter see,
the presence of more than one seemed always to be connected with the
absorption of decayed matter.

The inner side of the collar (see the previous fig. 20) is covered with
several crowded rows of processes, differing in no important respect
from the quadrifids, except in bearing only two arms instead of four;
they are, however, rather narrower and more delicate. I shall call them
the bifids. They project into the bladder, and are directed towards its
posterior end. The quadrifid and bifid processes no doubt are
homologous with the papillae on the outside of the bladder and of the
leaves; and we shall see that they are developed from closely similar
papillae.

The Uses of the several Parts.--After the above long but necessary
description of the parts, we will turn to their uses. The bladders have
been supposed by some authors to serve as floats; but branches which
bore no bladders, and others from which they had been removed, floated
perfectly, owing to the air in the intercellular spaces. Bladders
containing dead and captured animals usually include bubbles of air,
but these cannot have been generated solely by the process of decay, as
I have often seen air in young, clean, and empty bladders; and some old
bladders with much decaying matter had no bubbles.

The real use of the bladders is to capture small aquatic animals, and
this they do on a large scale. In the first lot of plants, which I
received from the New Forest early in July, a large proportion of the
fully [page 405] grown bladders contained prey; in a second lot,
received in the beginning of August, most of the bladders were empty,
but plants had been selected which had grown in unusually pure water.
In the first lot, my son examined seventeen bladders, including prey of
some kind, and eight of these contained entomostracan crustaceans,
three larvae of insects, one being still alive, and six remnants of
animals so much decayed that their nature could not be distinguished. I
picked out five bladders which seemed very full, and found in them
four, five, eight, and ten crustaceans, and in the fifth a single much
elongated larva. In five other bladders, selected from containing
remains, but not appearing very full, there were one, two, four, two,
and five crustaceans. A plant of Utricularia vulgaris, which had been
kept in almost pure water, was placed by Cohn one evening into water
swarming with crustaceans, and by the next morning most of the bladders
contained these animals entrapped and swimming round and round their
prisons. They remained alive for several days; but at last perished,
asphyxiated, as I suppose, by the oxygen in the water having been all
consumed.  Freshwater worms were also found by Cohn in some bladders.
In all cases the bladders with decayed remains swarmed with living
Algae of many kinds, Infusoria, and other low organisms, which
evidently lived as intruders.

Animals enter the bladders by bending inwards the posterior free edge
of the valve, which from being highly elastic shuts again instantly. As
the edge is extremely thin, and fits closely against the edge of the
collar, both projecting into the bladder (see section, fig. 20), it
would evidently be very difficult for any animal to get out when once
imprisoned, and apparently they never do escape. To show how closely
the edge [page 406] fits, I may mention that my son found a Daphnia
which had inserted one of its antennae into the slit, and it was thus
held fast during a whole day. On three or four occasions I have seen
long narrow larvae, both dead and alive, wedged between the corner of
the valve and collar, with half their bodies within the bladder and
half out.

As I felt much difficulty in understanding how such minute and weak
animals, as are often captured, could force their way into the
bladders, I tried many experiments to ascertain how this was effected.
The free margin of the valve bends so easily that no resistance is felt
when a needle or thin bristle is inserted. A thin human hair, fixed to
a handle, and cut off so as to project barely 1/4 of an inch, entered
with some difficulty; a longer piece yielded instead of entering. On
three occasions minute particles of blue glass (so as to be easily
distinguished) were placed on valves whilst under water; and on trying
gently to move them with a needle, they disappeared so suddenly that,
not seeing what had happened, I thought that I had flirted them off;
but on examining the bladders, they were found safely enclosed. The
same thing occurred to my son, who placed little cubes of green
box-wood (about 1/60 of an inch, .423 mm.) on some valves; and thrice
in the act of placing them on, or whilst gently moving them to another
spot, the valve suddenly opened and they were engulfed. He then placed
similar bits of wood on other valves, and moved them about for some
time, but they did not enter.  Again, particles of blue glass were
placed by me on three valves, and extremely minute shavings of lead on
two other valves; after 1 or 2 hrs. none had entered, but in from 2 to
5 hrs. all five were enclosed. One of the particles of glass was a
[page 407] long splinter, of which one end rested obliquely on the
valve, and after a few hours it was found fixed, half within the
bladder and half projecting out, with the edge of the valve fitting
closely all round, except at one angle, where a small open space was
left. It was so firmly fixed, like the above-mentioned larvae, that the
bladder was torn from the branch and shaken, and yet the splinter did
not fall out. My son also placed little cubes (about 1/65 of an inch,
.391 mm.) of green box-wood, which were just heavy enough to sink in water, on three
valves. These were examined after 19 hrs. 30 m., and were still lying
on the valves; but after 22 hrs. 30 m. one was found enclosed. I may
here mention that I found in a bladder on a naturally growing plant a
grain of sand, and in another bladder three grains; these must have
fallen by some accident on the valves, and then entered like the
particles of glass.

The slow bending of the valve from the weight of particles of glass and
even of box-wood, though largely supported by the water, is, I suppose,
analogous to the slow bending of colloid substances. For instance,
particles of glass were placed on various points of narrow strips of
moistened gelatine, and these yielded and became bent with extreme
slowness. It is much more difficult to understand how gently moving a
particle from one part of a valve to another causes it suddenly to
open. To ascertain whether the valves were endowed with irritability,
the surfaces of several were scratched with a needle or brushed with a
fine camel-hair brush, so as to imitate the crawling movement of small
crustaceans, but the valve did not open.  Some bladders, before being
brushed, were left for a time in water at temperatures between 80o and
130o F. (26o.6-54o.4 Cent.), as, judging from a wide- [page 408] spread
analogy, this would have rendered them more sensitive to irritation, or
would by itself have excited movement; but no effect was produced. We
may, therefore, conclude that animals enter merely by forcing their way
through the slit-like orifice; their heads serving as a wedge. But I am
surprised that such small and weak creatures as are often captured (for
instance, the nauplius of a crustacean, and a tardigrade) should be
strong enough to act in this manner, seeing that it was difficult to
push in one end of a bit of a hair 1/4 of an inch in length.
Nevertheless, it is certain that weak and small creatures do enter, and
Mrs. Treat, of New Jersey, has been more successful than any other
observer, and has often witnessed in the case of Utricularia
clandestina the whole process.* She saw a tardigrade slowly walking
round a bladder, as if reconnoitring; at last it crawled into the
depression where the valve lies, and then easily entered. She also
witnessed the entrapment of various minute crustaceans. Cypris "was
"quite wary, but nevertheless was often caught. "Coming to the entrance
of a bladder, it would some-"times pause a moment, and then dash away;
at "other times it would come close up, and even ven-"ture part of the
way into the entrance and back out "as if afraid. Another, more
heedless, would open "the door and walk in; but it was no sooner in
than "it manifested alarm, drew in its feet and antennae, and closed
its shell." Larvae, apparently of gnats, when "feeding near the
entrance, are pretty certain "to run their heads into the net, whence
there is no "retreat. A large larva is sometimes three or four "hours
in being swallowed, the process bringing to

* 'New York Tribune,' reprinted in the 'Gard. Chron.' 1875, p. 303.
[page 409]

"mind what I have witnessed when a small snake "makes a large frog its
victim." But as the valve does not appear to be in the least irritable,
the slow swallowing process must be the effect of the onward movement
of the larva.

It is difficult to conjecture what can attract so many creatures,
animal- and vegetable-feeding crustaceans, worms, tardigrades, and
various larvae, to enter the bladders. Mrs. Treat says that the larvae
just referred to are vegetable-feeders, and seem to have a special
liking for the long bristles round the valve, but this taste will not
account for the entrance of animal-feeding crustaceans. Perhaps small
aquatic animals habitually try to enter every small crevice, like that
between the valve and collar, in search of food or protection. It is
not probable that the remarkable transparency of the valve is an
accidental circumstance, and the spot of light thus formed may serve as
a guide. The long bristles round the entrance apparently serve for the
same purpose. I believe that this is the case, because the bladders of
some epiphytic and marsh species of Utricularia which live embedded
either in entangled vegetation or in mud, have no bristles round the
entrance, and these under such conditions would be of no service as a
guide. Nevertheless, with these epiphytic and marsh species, two pairs
of bristles project from the surface of the valve, as in the aquatic
species; and their use probably is to prevent too large animals from
trying to force an entrance into the bladder, thus rupturing orifice.

As under favourable circumstances most of the bladders succeed in
securing prey, in one case as many as ten crustaceans;--as the valve is
so well fitted to [page 410] allow animals to enter and to prevent
their escape;--and as the inside of the bladder presents so singular a
structure, clothed with innumerable quadrifid and bifid processes, it
is impossible to doubt that the plant has been specially adapted for
securing prey. From the analogy of Pinguicula, belonging to the same
family, I naturally expected that the bladders would have digested
their prey; but this is not the case, and there are no glands fitted
for secreting the proper fluid. Nevertheless, in order to test their
power of digestion, minute fragments of roast meat, three small cubes
of albumen, and three of cartilage, were pushed through the orifice
into the bladders of vigorous plants. They were left from one day to
three days and a half within, and the bladders were then cut open; but
none of the above substances exhibited the least signs of digestion or
dissolution; the angles of the cubes being as sharp as ever. These
observations were made subsequently to those on Drosera, Dionaea,
Drosophyllum, and Pinguicula; so that I was familiar with the
appearance of these substances when undergoing the early and final
stages of digestion. We may therefore conclude that Utricularia cannot
digest the animals which it habitually captures.

In most of the bladders the captured animals are so much decayed that
they form a pale brown, pulpy mass, with their chitinous coats so
tender that they fall to pieces with the greatest ease. The black
pigment of the eye-spots is preserved better than anything else.
Limbs, jaws, &c. are often found quite detached; and this I suppose is
the result of the vain struggles of the later captured animals. I have
sometimes felt surprised at the small proportion of imprisoned animals
in a fresh state compared with those utterly decayed. Mrs.  Treat
states with respect [page 411] to the larvae above referred to, that
"usually in less "than two days after a large one was captured the
fluid "contents of the bladders began to assume a cloudy "or muddy
appearance, and often became so dense "that the outline of the animal
was lost to view." This statement raises the suspicion that the
bladders secrete some ferment hastening the process of decay.  There is
no inherent improbability in this supposition, considering that meat
soaked for ten minutes in water mingled with the milky juice of the
papaw becomes quite tender and soon passes, as Browne remarks in his
'Natural History of Jamaica,' into a state of putridity.

Whether or not the decay of the imprisoned animals is an any way
hastened, it is certain that matter is absorbed from them by the
quadrifid and bifid processes. The extremely delicate nature of the
membrane of which these processes are formed, and the large surface
which they expose, owing to their number crowded over the whole
interior of the bladder, are circumstances all favouring the process of
absorption. Many perfectly clean bladders which had never caught any
prey were opened, and nothing could be distinguished with a No. 8
object-glass of Hartnack within the delicate, structureless
protoplasmic lining of the arms, excepting in each a single yellowish
particle or modified nucleus. Sometimes two or even three such
particles were present; but in this case traces of decaying matter
could generally be detected. On the other hand, in bladders containing
either one large or several small decayed animals, the processes
presented a widely different appearance. Six such bladders were
carefully examined; one contained an elongated, coiled-up larva;
another a single large entomostracan crustacean, and the others from
two to five smaller ones, all [page 412] in a decayed state. In these
six bladders, a large number of the quadrifid processes contained
transparent, often yellowish, more or less confluent, spherical or
irregularly shaped, masses of matter. Some of the processes, however,
contained only fine granular matter, the particles of which were so
small that they could not be defined clearly with No. 8 of Hartnack.
The delicate layer of protoplasm lining their walls was in some cases a
little shrunk. On three occasions the above small masses of matter were
observed and sketched at short intervals of time; and they certainly
changed their positions relatively to each other and to the walls of
the arms. Separate masses sometimes became confluent, and then again
divided. A single little mass would send out a projection, which after
a time separated itself. Hence there could be no doubt that these
masses consisted of protoplasm. Bearing in mind that many clean
bladders were examined with equal care, and that these presented no
such appearance, we may confidently believe that the protoplasm in the
above cases had been generated by the absorption of nitrogenous matter
from the decaying animals. In two or three other bladders, which at
first appeared quite clean, on careful search a few processes were
found, with their outsides clogged with a little brown matter, showing
that some minute animal had been captured and had decayed, and the arms
here included a very few more or less spherical and aggregated masses;
the processes in other parts of the bladders being empty and
transparent.  On the other hand, it must be stated that in three
bladders containing dead crustaceans, the processes were likewise
empty. This fact may be accounted for by the animals not having been
sufficiently decayed, or by time enough not having been allowed for the
generation of proto- [page 413] plasm, or by its subsequent absorption
and transference to other parts of the plant. It will hereafter be seen
that in three or four other species of Utricularia the quadrifid
processes in contact with decaying animals likewise contained
aggregated masses of protoplasm.

On the Absorption of certain Fluids by the Quadrifid and Bifid
processes.--These experiments were tried to ascertain whether certain
fluids, which seemed adapted for the purpose, would produce the same
effects on the processes as the absorption of decayed animal matter.
Such experiments are, however, troublesome; for it is not sufficient
merely to place a branch in the fluid, as the valve shuts so closely
that the fluid apparently does not enter soon, if at all. Even when
bristles were pushed into the orifices, they were in several cases
wrapped so closely round by the thin flexible edge of the valve that
the fluid was apparently excluded; so that the experiments tried in
this manner are doubtful and not worth giving. The best plan would have
been to puncture the bladders, but I did not think of this till too
late, excepting in a few cases. In all such trials, however, it cannot
be ascertained positively that the bladder, though translucent, does
not contain some minute animal in the last stage of decay. Therefore
most of my experiments were made by cutting bladders longitudinally
into two; the quadrifids were examined with No. 8 of Hartnack, then
irrigated, whilst under the covering glass, with a few drops of the
fluid under trial, kept in a damp chamber, and re-examined after stated
intervals of time with the same power as before.

[Four bladders were first tried as a control experiment, in the manner
just described, in a solution of one part of gum arabic to 218 of
water, and two bladders in a solution of one part of sugar to 437 of
water; and in neither case was any [page 414] change perceptible in the
quadrifids or bifids after 21 hrs. Four bladders were then treated in
the same manner with a solution of one part of nitrate of ammonia to
437 of water, and re-examined after 21 hrs. In two of these the
quadrifids now appeared full of very finely granular matter, and their
protoplasmic lining or primordial utricle was a little shrunk. In the
third bladder, the quadrifids included distinctly visible granules, and
the primordial utricle was a little shrunk after only 8 hrs. In the
fourth bladder the primordial utricle in most of the processes was here
and there thickened into little, irregular, yellowish specks; and from
the gradations which could be traced in this and other cases, these
specks appear to give rise to the larger free granules contained within
some of the processes. Other bladders, which, as far as could be
judged, had never caught any prey, were punctured and left in the same
solution for 17 hrs.; and their quadrifids now contained very fine
granular matter.

A bladder was bisected, examined, and irrigated with a solution of one
part of carbonate of ammonia to 437 of water. After 8 hrs. 30 m. the
quadrifids contained a good many granules, and the primordial utricle
was somewhat shrunk; after 23 hrs. the quadrifids and bifids contained
many spheres of hyaline matter, and in one arm twenty-four such spheres
of moderate size were counted. Two bisected bladders, which had been
previously left for 21 hrs. in the solution of gum (one part to 218 of
water) without being affected, were irrigated with the solution of
carbonate of ammonia; and both had their quadrifids modified in nearly
the same manner as just described,--one after only 9 hrs., and the
other after 24 hrs. Two bladders which appeared never to have caught
any prey were punctured and placed in the solution; the quadrifids of
one were examined after 17 hrs., and found slightly opaque; the
quadrifids of the other, examined after 45 hrs., had their primordial
utricles more or less shrunk with thickened yellowish specks, like
those due to the action of nitrate of ammonia.  Several uninjured
bladders were left in the same solution, as well as a weaker solution
of one part to 1750 of water, or 1 gr. to 4 oz.; and after two days the
quadrifids were more or less opaque, with their contents finely
granular; but whether the solution had entered by the orifice, or had
been absorbed from the outside, I know not.

Two bisected bladders were irrigated with a solution of one part of
urea to 218 of water; but when this solution was employed, I forgot
that it had been kept for some days in a warm room, and had therefore
probably generated ammonia; anyhow [page 415] the quadrifids were
affected after 21 hrs. as if a solution of carbonate of ammonia had
been used; for the primordial utricle was thickened in specks, which
seemed to graduate into separate granules. Three bisected bladders were
also irrigated with a fresh solution of urea of the same strength;
their quadrifids after 21 hrs. were much less affected than in the
former case; nevertheless, the primordial utricle in some of the arms
was a little shrunk, and in others was divided into two almost
symmetrical sacks.

Three bisected bladders, after being examined, were irrigated with a
putrid and very offensive infusion of raw meat. After 23 hrs. the
quadrifids and bifids in all three specimens abounded with minute,
hyaline, spherical masses; and some of their primordial utricles were a
little shrunk. Three bisected bladders were also irrigated with a fresh
infusion of raw meat; and to my surprise the quadrifids in one of them
appeared, after 23 hrs., finely granular, with their primordial
utricles somewhat shrunk and marked with thickened yellowish specks; so
that they had been acted on in the same manner as by the putrid
infusion or by the salts of ammonia. In the second bladder some of the
quadrifids were similarly acted on, though to a very slight degree;
whilst the third bladder was not at all affected.]

From these experiments it is clear that the quadrifid and bifid
processes have the power of absorbing carbonate and nitrate of ammonia,
and matter of some kind from a putrid infusion of meat. Salts of
ammonia were selected for trial, as they are known to be rapidly
generated by the decay of animal matter in the presence of air and
water, and would therefore be generated within the bladders containing
captured prey. The effect produced on the processes by these salts and
by a putrid infusion of raw meat differs from that produced by the
decay of the naturally captured animals only in the aggregated masses
of protoplasm being in the latter case of larger size; but it is
probable that the fine granules and small hyaline spheres produced by
the solutions would coalesce into larger masses, with time enough
allowed.  [page 416] We have seen with Drosera that the first effect of
a weak solution of carbonate of ammonia on the cell-contents is the
production of the finest granules, which afterwards aggregate into
larger, more or less rounded, masses; and that the granules in the
layer of protoplasm which flows round the walls ultimately coalesce
with these masses. Changes of this nature are, however, far more rapid
in Drosera than in Utricularia. Since the bladders have no power of
digesting albumen, cartilage, or roast meat, I was surprised that
matter was absorbed, at least in one case, from a fresh infusion of raw
meat. I was also surprised, from what we shall presently see with
respect to the glands round the orifice, that a fresh solution of urea
produced only a moderate effect on the quadrifids.

As the quadrifids are developed from papillae which at first closely
resemble those on the outside of the bladders and on the surfaces of
the leaves, I may here state that the two hemispherical cells with
which these latter papillae are crowned, and which in their natural
state are perfectly transparent, likewise absorb carbonate and nitrate
of ammonia; for, after an immersion of 23 hrs. in solutions of one part
of both these salts to 437 of water, their primordial utricles were a
little shrunk and of a pale brown tint, and sometimes finely granular.
The same result followed from the immersion of a whole branch for
nearly three days in a solution of one part of the carbonate to 1750 of
water. The grains of chlorophyll, also, in the cells of the leaves on
this branch became in many places aggregated into little green masses,
which were often connected together by the finest threads.

On the Absorption of certain Fluids by the Glands on the Valve and
Collar.--The glands round the orifices of bladders which are still
young, or which have been [page 417] long kept in moderately pure
water, are colourless; and their primordial utricles are only slightly
or hardly at all granular. But in the greater number of plants in a
state of nature--and we must remember that they generally grow in very
foul water--and with plants kept in an aquarium in foul water, most of
the glands were of a pale brownish tint; their primordial utricles were
more or less shrunk, sometimes ruptured, with their contents often
coarsely granular or aggregated into little masses. That this state of
the glands is due to their having absorbed matter from the surrounding
water, I cannot doubt; for, as we shall immediately see, nearly the
same results follow from their immersion for a few hours in various
solutions.  Nor is it probable that this absorption is useless, seeing
that it is almost universal with plants growing in a state of nature,
excepting when the water is remarkably pure.

The pedicels of the glands which are situated close to the slit-like
orifice, both those on the valve and on the collar, are short; whereas
the pedicels of the more distant glands are much elongated and project
inwards. The glands are thus well placed so to be washed by any fluid
coming out of the bladder through the orifice. The valve fits so
closely, judging from the result of immersing uninjured bladders in
various solutions, that it is doubtful whether any putrid fluid
habitually passes outwards. But we must remember that a bladder
generally captures several animals; and that each time a fresh animal
enters, a puff of foul water must pass out and bathe the glands.
Moreover, I have repeatedly found that, by gently pressing bladders
which contained air, minute bubbles were driven out through the
orifice; and if a bladder is laid on blotting paper and gently pressed,
water oozes out.  [page 418] In this latter case, as soon as the
pressure is relaxed, air is drawn in, and the bladder recovers its
proper form. If it is now placed under water and again gently pressed,
minute bubbles issue from the orifice and nowhere else, showing that
the walls of the bladder have not been ruptured. I mention this because
Cohn quotes a statement by Treviranus, that air cannot be forced out of
a bladder without rupturing it. We may therefore conclude that whenever
air is secreted within a bladder already full of water, some water will
be slowly driven out through the orifice. Hence I can hardly doubt that
the numerous glands crowded round the orifice are adapted to absorb
matter from the putrid water, which will occasionally escape from
bladders including decayed animals.

[In order to test this conclusion, I experimented with various
solutions on the glands. As in the case of the quadrifids, salts of
ammonia were tried, since these are generated by the final decay of
animal matter under water. Unfortunately the glands cannot be carefully
examined whilst attached to the bladders in their entire state. Their
summits, therefore, including the valve, collar, and antennae, were
sliced off, and the condition of the glands observed; they were then
irrigated, whilst beneath a covering glass, with the solutions, and
after a time re-examined with the same power as before, namely No. 8 of
Hartnack. The following experiments were thus made.

As a control experiment solutions of one part of white sugar and of one
part of gum to 218 of water were first used, to see whether these
produced any change in the glands. It was also necessary to observe
whether the glands were affected by the summits of the bladders having
been cut off. The summits of four were thus tried; one being examined
after 2 hrs. 30 m., and the other three after 23 hrs.; but there was no
marked change in the glands of any of them.

Two summits bearing quite colourless glands were irrigated with a
solution of carbonate of ammonia of the same strength (viz. one part to
218 of water) , and in 5 m. the primordial utricles of most of the
glands were somewhat contracted; they were also thickened in specks or
patches, and had assumed a pale [page 419] brown tint. When looked at
again after 1 hr. 30 m., most of them presented a somewhat different
appearance. A third specimen was treated with a weaker solution of one
part of the carbonate to 437 of water, and after 1 hr. the glands were
pale brown and contained numerous granules.

Four summits were irrigated with a solution of one part of nitrate of
ammonia to 437 of water. One was examined after 15 m., and the glands
seemed affected; after 1 hr. 10 m. there was a greater change, and the
primordial utricles in most of them were somewhat shrunk, and included
many granules. In the second specimen, the primordial utricles were
considerably shrunk and brownish after 2 hrs. Similar effects were
observed in the two other specimens, but these were not examined until
21 hrs. had elapsed. The nuclei of many of the glands apparently had
increased in size. Five bladders on a branch, which had been kept for a
long time in moderately pure water, were cut off and examined, and
their glands found very little modified. The remainder of this branch
was placed in the solution of the nitrate, and after 21 hrs. two
bladders were examined, and all their glands were brownish, with their
primordial utricles somewhat shrunk and finely granular.

The summit of another bladder, the glands of which were in a
beautifully clear condition, was irrigated with a few drops of a mixed
solution of nitrate and phosphate of ammonia, each of one part to 437
of water. After 2 hrs. some few of the glands were brownish. After 8
hrs.  almost all the oblong glands were brown and much more opaque than
they were before; their primordial utricles were somewhat shrunk and
contained a little aggregated granular matter.  The spherical glands
were still white, but their utricles were broken up into three or four
small hyaline spheres, with an irregularly contracted mass in the
middle of the basal part.  These smaller spheres changed their forms in
the course of a few hours and some of them disappeared. By the next
morning, after 23 hrs. 30 m., they had all disappeared, and the glands
were brown; their utricles now formed a globular shrunken mass in the
middle. The utricles of the oblong glands had shrunk very little, but
their contents were somewhat aggregated. Lastly, the summit of a
bladder which had been previously irrigated for 21 hrs.  with a
solution of one part of sugar to 218 of water without being affected,
was treated with the above mixed solution; and after 8 hrs. 30 m. all
the glands became brown, with their primordial utricles slightly
shrunk.

Four summits were irrigated with a putrid infusion of raw [page 420]
meat. No change in the glands was observable for some hours, but after
24 hrs. most of them had become brownish, and more opaque and granular
than they were before. In these specimens, as in those irrigated with
the salts of ammonia, the nuclei seemed to have increased both in size
and solidity, but they were not measured. Five summits were also
irrigated with a fresh infusion of raw meat; three of these were not at
all affected in 24 hrs., but the glands of the other two had perhaps
become more granular. One of the specimens which was not affected was
then irrigated with the mixed solution of the nitrate and phosphate of
ammonia, and after only 25 m. the glands contained from four or five to
a dozen granules. After six additional hours their primordial utricles
were greatly shrunk.

The summit of a bladder was examined, and all the glands found
colourless, with their primordial utricles not at all shrunk; yet many
of the oblong glands contained granules just resolvable with No. 8 of
Hartnack. It was then irrigated with a few drops of a solution of one
part of urea to 218 of water. After 2 hrs. 25 m. the spherical glands
were still colourless; whilst the oblong and two-armed ones were of a
brownish tint, and their primordial utricles much shrunk, some
containing distinctly visible granules. After 9 hrs. some of the
spherical glands were brownish, and the oblong glands were still more
changed, but they contained fewer separate granules; their nuclei, on
the other hand, appeared larger, as if they had absorbed the granules.
After 23 hrs. all the glands were brown, their primordial utricles
greatly shrunk, and in many cases ruptured.

A bladder was now experimented on, which was already somewhat affected
by the surrounding water; for the spherical glands, though colourless,
had their primordial utricles slightly shrunk; and the oblong glands
were brownish, with their utricles much, but irregularly, shrunk. The
summit was treated with the solution of urea, but was little affected
by it in 9 hrs.; nevertheless, after 23 hrs. the spherical glands were
brown, with their utricles more shrunk; several of the other glands
were still browner, with their utricles contracted into irregular
little masses.

Two other summits, with their glands colourless and their utricles not
shrunk, were treated with the same solution of urea. After 5 hrs. many
of the glands presented a shade of brown, with their utricles slightly
shrunk. After 20 hrs. 40 m. some few of them were quite brown, and
contained [page 421] irregularly aggregated masses; others were still
colourless, though their utricles were shrunk; but the greater number
were not much affected. This was a good instance of how unequally the
glands on the same bladder are sometimes affected, as likewise often
occurs with plants growing in foul water. Two other summits were
treated with a solution which had been kept during several days in a
warm room, and their glands were not at all affected when examined
after 21 hrs.

A weaker solution of one part of urea to 437 of water was next tried on
six summits, all carefully examined before being irrigated. The first
was re-examined after 8 hrs. 30 m., and the glands, including the
spherical ones, were brown; many of the oblong glands having their
primordial utricles much shrunk and including granules. The second
summit, before being irrigated, had been somewhat affected by the
surrounding water, for the spherical glands were not quite uniform in
appearance; and a few of the oblong ones were brown, with their
utricles shrunk. Of the oblong glands, those which were before
colourless, became brown in 3 hrs. 12 m. after irrigation, with their
utricles slightly shrunk. The spherical glands did not become brown,
but their contents seemed changed in appearance, and after 23 hrs.
still more changed and granular. Most of the oblong glands were now
dark brown, but their utricles were not greatly shrunk. The four other
specimens were examined after 3 hrs. 30 m., after 4 hrs., and 9 hrs.; a
brief account of their condition will be sufficient. The spherical
glands were not brown, but some of them were finely granular. Many of
the oblong glands were brown, and these, as well as others which still
remained colourless, had their utricles more or less shrunk, some of
them including small aggregated masses of matter.]

Summary of the Observations on Absorption.--From the facts now given
there can be no doubt that the variously shaped glands on the valve and
round the collar have the power of absorbing matter from weak solutions
of certain salts of ammonia and urea, and from a putrid infusion of raw
meat. Prof. Cohn believes that they secrete slimy matter; but I was not
able to perceive any trace of such action, excepting that, after
immersion in alcohol, extremely fine lines could sometimes be seen
radiating from their [page 422] surfaces. The glands are variously
affected by absorption; they often become of a brown colour; sometimes
they contain very fine granules, or moderately sized grains, or
irregularly aggregated little masses; sometimes the nuclei appear to
have increased in size; the primordial utricles are generally more or
less shrunk and sometimes ruptured. Exactly the same changes may be
observed in the glands of plants growing and flourishing in foul
water.  The spherical glands are generally affected rather differently
from the oblong and two-armed ones. The former do not so commonly
become brown, and are acted on more slowly. We may therefore infer that
they differ somewhat in their natural functions.

It is remarkable how unequally the glands on the bladders on the same
branch, and even the glands of the same kind on the same bladder, are
affected by the foul water in which the plants have grown, and by the
solutions which were employed. In the former case I presume that this
is due either to little currents bringing matter to some glands and not
to others, or to unknown differences in their constitution. When the
glands on the same bladder are differently affected by a solution, we
may suspect that some of them had previously absorbed a small amount of
matter from the water. However this may be, we have seen that the
glands on the same leaf of Drosera are sometimes very unequally
affected, more especially when exposed to certain vapours.

If glands which have already become brown, with their primordial
utricles shrunk, are irrigated with one of the effective solutions,
they are not acted on, or only slightly and slowly. If, however, a
gland contains merely a few coarse granules, this does not prevent a
solution from acting. I have never seen [page 423] any appearance
making it probable that glands which have been strongly affected by
absorbing matter of any kind are capable of recovering their pristine,
colourless, and homogeneous condition, and of regaining the power of
absorbing.

From the nature of the solutions which were tried, I presume that
nitrogen is absorbed by the glands; but the modified, brownish, more or
less shrunk, and aggregated contents of the oblong glands were never
seen by me or by my son to undergo those spontaneous changes of form
characteristic of protoplasm. On the other hand, the contents of the
larger spherical glands often separated into small hyaline globules or
irregularly shaped masses, which changed their forms very slowly and
ultimately coalesced, forming a central shrunken mass.  Whatever may be
the nature of the contents of the several kinds of glands, after they
have been acted on by foul water or by one of the nitrogenous
solutions, it is probable that the matter thus generated is of service
to the plant, and is ultimately transferred to other parts.

The glands apparently absorb more quickly than do the quadrifid and
bifid processes; and on the view above maintained, namely that they
absorb matter from putrid water occasionally emitted from the bladders,
they ought to act more quickly than the processes; as these latter
remain in permanent contact with captured and decaying animals.

Finally, the conclusion to which we are led by the foregoing
experiments and observations is that the bladders have no power of
digesting animal matter, though it appears that the quadrifids are
somewhat affected by a fresh infusion of raw meat. It is certain that
the processes within the bladders, and the glands outside, absorb
matter from salts of [page 424] ammonia, from a putrid infusion of raw
meat, and from urea. The glands apparently are acted on more strongly
by a solution of urea, and less strongly by an infusion of raw meat,
than are the processes. The case of urea is particularly interesting,
because we have seen that it produces no effect on Drosera, the leaves
of which are adapted to digest fresh animal matter.  But the most
important fact of all is, that in the present and following species the
quadrifid and bifid processes of bladders containing decayed animals
generally include little masses of spontaneously moving protoplasm;
whilst such masses are never seen in perfectly clean bladders.

Development of the Bladders.--My son and I spent much time over this
subject with small success. Our observations apply to the present
species and to Utricularia vulgaris, but were made chiefly on the
latter, as the bladders are twice as large as those of Utricularia
neglecta.  In the early part of autumn the stems terminate in large
buds, which fall off and lie dormant during the winter at the bottom.
The young leaves forming these buds bear bladders in various stages of
early development. When the bladders of Utricularia vulgaris are about
1/100 inch (.254 mm.) in diameter (or 1/200 in the case of Utricularia
neglecta), they are circular in outline, with a narrow, almost closed,
transverse orifice, leading into a hollow filled with water; but the
bladders are hollow when much under 1/100 of an inch in diameter.  The
orifices face inwards or towards the axis of the plant. At this early
age the bladders are flattened in the plane in which the orifice lies,
and therefore at right angles to that of the mature bladders. They are
covered exteriorly with papillae of different sizes, many of which have
an elliptical outline. A bundle of vessels, formed of [page 425] simple
elongated cells, runs up the short footstalk, and divides at the base
of the bladder. One branch extends up the middle of the dorsal surface,
and the other up the middle of the ventral surface. In full-grown
bladders the ventral bundle divides close beneath the collar, and the
two branches run on each side to near where the corners of the valve
unite with the collar; but these branches could not be seen in very
young bladders.

FIG. 23.  (Utricularia vulgaris.) Longitudinal section through a young
bladder, 1/100 of an inch in length, with the orifice too widely open.

The accompanying figure (fig. 23) shows a section, which happened to be
strictly medial, through the footstalk and between the nascent antennae
of a bladder of Utricularia vulgaris, 1/100 inch in diameter. The
specimen was soft, and the young valve became separated from the collar
to a greater degree than is natural, and is thus represented. We here
clearly see that the valve and collar are infolded prolongations of the
walls of the bladder. Even at this early age, glands could be detected
on the valve. The state of the quadrifid processes will presently be
described. The antennae at this period consist of minute cellular
projections (not shown in the above figure, as they do not lie in the
medial plane), which soon bear incipient bristles. In five instances
the young antennae were not of quite equal length; and this fact is
intelligible if I am right in believing that they represent two
divisions of the leaf, rising from the end of the bladder; for, with
the true leaves, whilst very young, the divisions are never, as far as
I have seen, strictly opposite; they [page 426] must therefore be
developed one after the other, and so it would be with the two
antennae.

At a much earlier age, when the half formed bladders are only 1/300
inch (.0846 mm.) in diameter or a little more, they present a totally
different appearance. One is represented on the left side of the
accompanying drawing (fig. 24). The young leaves

FIG. 24.  (Utricularia vulgaris.) Young leaf from a winter bud, showing
on the left side a bladder in its earliest stage of development.

at this age have broad flattened segments, with their future divisions
represented by prominences, one of which is shown on the right side.
Now, in a large number of specimens examined by my son, the young
bladders appeared as if formed by the oblique folding over of the apex
and of one margin with a prominence, against the opposite margin. The
circular hollow between the infolded apex and infolded prominence
apparently contracts into the narrow orifice, wherein the valve and
collar will be developed; the bladder itself being formed by the
confluence of the opposed [page 427] margins of the rest of the leaf.
But strong objections may be urged against this view, for we must in
this case suppose that the valve and collar are developed
asymmetrically from the sides of the apex and prominence. Moreover, the
bundles of vascular tissue have to be formed in lines quite
irrespective of the original form of the leaf. Until gradations can be
shown to exist between this the earliest state and a young yet perfect
bladder, the case must be left doubtful.

As the quadrifid and bifid processes offer one of the greatest
peculiarities in the genus, I carefully observed their development in
Utricularia neglecta. In bladders about 1/100 of an inch in diameter,
the inner surface is studded with papillae, rising from small cells at
the junctions of the larger ones. These papillae consist of a delicate
conical protuberance, which narrows into a very short footstalk,
surmounted by two minute cells. They thus occupy the same relative
position, and closely resemble, except in being smaller and rather more
prominent, the papillae on the outside of the bladders, and on the
surfaces of the leaves. The two terminal cells of the papillae first
become much elongated in a line parallel to the inner surface of the
bladder. Next, each is divided by a longitudinal partition. Soon the
two half-cells thus formed separate from one another; and we now have
four cells or an incipient quadrifid process. As there is not space for
the two new cells to increase in breadth in their original plane, the
one slides partly under the other. Their manner of growth now changes,
and their outer sides, instead of their apices, continue to grow. The
two lower cells, which have slid partly beneath the two upper ones,
form the longer and more upright pair of processes; whilst the two
upper cells form the shorter [page 428] and more horizontal pair; the
four together forming a perfect quadrifid. A trace of the primary
division between the two cells on the summits of the papillae can still
be seen between the bases of the longer processes. The development of
the quadrifids is very liable to be arrested. I have seen a bladder
1/50 of an inch in length including only primordial papillae; and
another bladder, about half its full size, with the quadrifids in an
early stage of development.

As far as I could make out, the bifid processes are developed in the
same manner as the quadrifids, excepting that the two primary terminal
cells never become divided, and only increase in length. The glands on
the valve and collar appear at so early an age that I could not trace
their development; but we may reasonably suspect that they are
developed from papillae like those on the outside of the bladder, but
with their terminal cells not divided into two. The two segments
forming the pedicels of the glands probably answer to the conical
protuberance and short footstalk of the quadrifid and bifid processes.
I am strengthened in the belief that the glands are developed from
papillae like those on the outside of the bladders, from the fact that
in Utricularia amethystina the glands extend along the whole ventral
surface of the bladder close to the footstalk.

                    [UTRICULARIA VULGARIS.

Living plants from Yorkshire were sent me by Dr. Hooker. This species
differs from the last in the stems and leaves being thicker or coarser;
their divisions form a more acute angle with one another; the notches
on the leaves bear three or four short bristles instead of one; and the
bladders are twice as large, or about 1/5 of an inch (5.08 mm.) in
diameter. In all essential respects the bladders resemble those of
Utricularia neglecta, but the sides of the peristome are perhaps a
little more [page 429] prominent, and always bear, as far as I have
seen, seven or eight long multicellular bristles.  There are eleven
long bristles on each antenna, the terminal pair being included. Five
bladders, containing prey of some kind, were examined. The first
included five Cypris; a large copepod and a Diaptomus; the second,
four Cypris; the third, a single rather large crustacean; the fourth,
six crustaceans; and the fifth, ten. My son examined the quadrifid
processes in a bladder containing the remains of two crustaceans, and
found some of them full of spherical or irregularly shaped masses of
matter, which were observed to move and to coalesce. These masses
therefore consisted of protoplasm.

                      UTRICULARIA MINOR.

FIG. 25.  (Utricularia minor.) Quadrifid process, greatly enlarged.

This rare species was sent me in a living state from Cheshire, through
the kindness of Mr.  John Price. The leaves and bladders are much
smaller than those of Utricularia neglecta. The leaves bear fewer and
shorter bristles, and the bladders are more globular. The antennae,
instead of projecting in front of the bladders, are curled under the
valve, and are armed with twelve or fourteen extremely long
multicellular bristles, generally arranged in pairs. These, with seven
or eight long bristles on both sides of the peristome, form a sort of
net over the valve, which would tend to prevent all animals, excepting
very small ones, entering the bladder. The valve and collar have the
same essential structure as in the two previous species; but the glands
are not quite so numerous; the oblong ones are rather more elongated,
whilst the two-armed ones are rather less elongated. The four bristles
which project obliquely from the lower edge of the valve are short.
Their shortness, compared with those on the valves of the foregoing
species, is intelligible if my view is correct that they serve to
prevent too large animals forcing an entrance through the valve, thus
injuring it; for the valve is already protected to a certain extent by
the incurved antennae, together with the lateral bristles. The bifid
processes are like those in the previous species; but the quadrifids
differ in the four arms (fig. 25) [page 430] being directed to the same
side; the two longer ones being central, and the two shorter ones on
the outside.

The plants were collected in the middle of July; and the contents of
five bladders, which from their opacity seemed full of prey, were
examined. The first contained no less than twenty-four minute
fresh-water crustaceans, most of them consisting of empty shells, or
including only a few drops of red oily matter; the second contained
twenty; the third, fifteen; the fourth, ten, some of them being rather
larger than usual; and the fifth, which seemed stuffed quite full,
contained only seven, but five of these were of unusually large size.
The prey, therefore, judging from these five bladders, consists
exclusively of fresh-water crustaceans, most of which appeared to be
distinct species from those found in the bladders of the two former
species. In one bladder the quadrifids in contact with a decaying mass
contained numerous spheres of granular matter, which slowly changed
their forms and positions.

                   UTRICULARIA CLANDESTINA.

This North American species, which is aquatic like the three foregoing
ones, has been described by Mrs. Treat, of New Jersey, whose excellent
observations have already been largely quoted. I have not as yet seen
any full description by her of the structure of the bladder, but it
appears to be lined with quadrifid processes. A vast number of captured
animals were found within the bladders; some being crustaceans, but the
greater number delicate, elongated larvae, I suppose of Culicidae. On
some stems, "fully nine out of every ten bladders contained these
larvae or their remains." The larvae "showed signs of life from
twenty-four to thirty-six hours after being imprisoned," and then
perished.  [page 431]


                         CHAPTER XVIII.

                    UTRICULARIA (continued).

Utricularia montana--Description of the bladders on the subterranean
rhizomes--Prey captured by the bladders of plants under culture and in
a state of nature--Absorption by the quadrifid processes and
glands--Tubers serving as reservoirs for water--Various other species
of Utricularia--Polypompholyx--Genlisea, different nature of the trap
for capturing prey-- Diversified methods by which plants are
nourished.

FIG. 26.  (Utricularia montana.) Rhizome swollen into a tuber; the
branches bearing minute bladders; of natural size.

UTRICULARIA MONTANA.--This species inhabits the tropical parts of South
America, and is said to be epiphytic; but, judging from the state of
the roots (rhizomes) of some dried specimens from the herbarium at Kew,
it likewise lives in earth, probably in crevices of rocks. In English
hothouses it is grown in peaty soil. Lady Dorothy Nevill was so kind as
to give me a fine plant, and I received another from Dr. Hooker. The
leaves are entire, instead of being much divided, as in the foregoing
aquatic species. They are elongated, about 1 1/2 inch in breadth, and
furnished with a distinct footstalk. The plant produces numerous
colourless rhizomes, as thin as threads, which bear minute bladders,
and occasionally swell into tubers, as will [page 432] hereafter be
described. These rhizomes appear exactly like roots, but occasionally
throw up green shoots. They penetrate the earth sometimes to the depth
of more than 2 inches; but when the plant grows as an epiphyte, they
must creep amidst the mosses, roots, decayed bark, &c., with which the
trees of these countries are thickly covered.

As the bladders are attached to the rhizomes, they are necessarily
subterranean. They are produced in extraordinary numbers. One of my
plants, though young, must have borne several hundreds; for a single
branch out of an entangled mass had thirty-two, and another branch,
about 2 inches in length (but with its end and one side branch broken
off), had seventy- three bladders.* The bladders are compressed and
rounded, with the ventral surface, or that between the summit of the
long delicate footstalk and valve, extremely short (fig. 27).  They are
colourless and almost as transparent as glass, so that they appear
smaller than they really are, the largest being under the 1/20 of an
inch (1.27 mm.) in its longer diameter. They are formed of rather large
angular cells, at the junctions of which oblong papillae project,
corresponding with those on the surfaces of the bladders of the
previous species. Similar papillae abound on the rhizomes, and even on
the entire leaves, but they are rather broader on the latter. Vessels,
marked with parallel bars instead of by a spiral line, run up the
footstalks, and

* Prof. Oliver has figured a plant of Utricularia Jamesoniana ('Proc.
Linn. Soc.' vol. iv. p.  169) having entire leaves and rhizomes, like
those of our present species; but the margins of the terminal halves of
some of the leaves are converted into bladders. This fact clearly
indicates that the bladders on the rhizomes of the present and
following species are modified segments of the leaf; and they are thus
brought into accordance with the bladders attached to the divided and
floating leaves of the aquatic species.  [page 433]

just enter the bases of the bladders; but they do not bifurcate and
extend up the dorsal and ventral surfaces, as in the previous species.

The antennae are of moderate length, and taper to a fine point; they
differ conspicuously from those before described, in not being armed
with bristles. Their bases are so abruptly curved that their tips
generally rest one on each side of the middle of the bladder, but

FIG. 27.  (Utricularia montana.) Bladder; about 27 times enlarged.

sometimes near the margin. Their curved bases thus form a roof over the
cavity in which the valve lies; but there is always left on each side a
little circular passage into the cavity, as may be seen in the drawing,
as well as a narrow passage between the bases of the two antennae.  As
the bladders are subterranean, had it not been for the roof, the cavity
in which the valve lies would have been liable to be blocked up with
earth [page 434] and rubbish; so that the curvature of the antennae is
a serviceable character. There are no bristles on the outside of the
collar or peristome, as in the foregoing species.

The valve is small and steeply inclined, with its free posterior edge
abutting against a semicircular, deeply depending collar. It is
moderately transparent, and bears two pairs of short stiff bristles, in
the same position as in the other species. The presence of these four
bristles, in contrast with the absence of those on the antennae and
collar, indicates that they are of functional importance, namely, as I
believe, to prevent too large animals forcing an entrance through the
valve. The many glands of diverse shapes attached to the valve and
round the collar in the previous species are here absent, with the
exception of about a dozen of the two-armed or transversely elongated
kind, which are seated near the borders of the valve, and are mounted
on very short footstalks. These glands are only the 3/4000 of an inch
(.019 mm.) in length; though so small, they act as absorbents. The
collar is thick, stiff, and almost semi-circular; it is formed of the
same peculiar brownish tissue as in the former species.

The bladders are filled with water, and sometimes include bubbles of
air. They bear internally rather short, thick, quadrifid processes
arranged in approximately concentric rows.  The two pairs of arms of
which they are formed differ only a little in length, and stand in a
peculiar position (fig. 28); the two longer ones forming one line, and
the two shorter ones another parallel line. Each arm includes a small
spherical mass of brownish matter, which, when crushed, breaks into
angular pieces. I have no doubt that these spheres are nuclei, for
closely similar ones [page 435] are present in the cells forming the
walls of the bladders. Bifid processes, having rather short oval arms,
arise in the usual position on the inner side of the collar.

These bladders, therefore, resemble in all essential respects the
larger ones of the foregoing species. They differ chiefly in the
absence of the numerous glands on the valve and round the collar, a few
minute ones of one kind alone being present on the valve. They differ
more conspicuously in the absence of the long bristles on the antennae
and on the outside of the collar. The presence of these bristles in the
previously mentioned species probably relates to the capture of aquatic
animals.

FIG. 28.  (Utricularia montana.) One of the quadrifid processes; much
enlarged.

It seemed to me an interesting question whether the minute bladders of
Utricularia montanaserved, as in the previous species, to capture
animals living in the earth, or in the dense vegetation covering the
trees on which this species is epiphytic; for in this case we should
have a new sub-class of carnivorous plants, namely, subterranean
feeders. Many bladders, therefore, were examined, with the following
results:--

[(1) A small bladder, less than 1/30 of an inch (.847 mm.) in diameter,
contained a minute mass of brown, much decayed matter; and in this, a
tarsus with four or five joints, terminating in a double hook, was
clearly distinguished under the microscope. I suspect that it was a
remnant of one of the Thysanoura. The quadrifids in contact with this
decayed remnant contained either small masses of translucent, yellowish
matter, generally more [page 436] or less globular, or fine granules.
In distant parts of the same bladder, the processes were transparent
and quite empty, with the exception of their solid nuclei. My son made
at short intervals of time sketches of one of the above aggregated
masses, and found that they continually and completely changed their
forms; sometimes separating from one another and again coalescing.
Evidently protoplasm had been generated by the absorption of some
element from the decaying animal matter.

(2) Another bladder included a still smaller speck of decayed brown
matter, and the adjoining quadrifids contained aggregated matter,
exactly as in the last case.

(3) A third bladder included a larger organism, which was so much
decayed that I could only make out that it was spinose or hairy. The
quadrifids in this case were not much affected, excepting that the
nuclei in the several arms differed much in size; some of them
containing two masses having a similar appearance.

(4) A fourth bladder contained an articulate organism, for I distinctly
saw the remnant of a limb, terminating in a hook. The quadrifids were
not examined.

(5) A fifth included much decayed matter apparently of some animal, but
with no recognisable features. The quadrifids in contact contained
numerous spheres of protoplasm.

(6) Some few bladders on the plant which I received from Kew were
examined; and in one, there was a worm-shaped animal very little
decayed, with a distinct remnant of a similar one greatly decayed.
Several of the arms of the processes in contact with these remains
contained two spherical masses, like the single solid nucleus which is
properly found in each arm. In another bladder there was a minute grain
of quartz, reminding me of two similar cases with Utricularia
neglecta.

As it appeared probable that this plant would capture a greater number
of animals in its native country than under culture, I obtained
permission to remove small portions of the rhizomes from dried
specimens in the herbarium at Kew. I did not at first find out that it
was advisable to soak the rhizomes for two or three days, and that it
was necessary to open the bladders and spread out their contents on
glass; as from their state of decay and from having been dried and
pressed, their nature could not otherwise be well distinguished.
Several bladders on a plant which had grown in black earth in New
Granada were first examined; and four of these included remnants of
animals. The first contained a hairy Acarus, so much decayed that
nothing was left except its transparent coat; [page 437] also a yellow
chitinous head of some animal with an internal fork, to which the
oesophagus was suspended, but I could see no mandibles; also the double
hook of the tarsus of some animal; also an elongated greatly decayed
animal; and lastly, a curious flask-shaped organism, having the walls
formed of rounded cells. Professor Claus has looked at this latter
organism, and thinks that it is the shell of a rhizopod, probably one
of the Arcellidae. In this bladder, as well as in several others, there
were some unicellular Algae, and one multicellular Alga, which no doubt
had lived as intruders.

A second bladder contained an Acarus much less decayed than the former
one, with its eight legs preserved; as well as remnants of several
other articulate animals. A third bladder contained the end of the
abdomen with the two hinder limbs of an Acarus, as I believe. A fourth
contained remnants of a distinctly articulated bristly animal, and of
several other organisms, as well as much dark brown organic matter, the
nature of which could not be made out.

Some bladders from a plant, which had lived as an epiphyte in Trinidad,
in the West Indies, were next examined, but not so carefully as the
others; nor had they been soaked long enough. Four of them contained
much brown, translucent, granular matter, apparently organic, but with
no distinguishable parts. The quadrifids in two were brownish, with
their contents granular; and it was evident that they had absorbed
matter. In a fifth bladder there was a flask-shaped organism, like that
above mentioned. A sixth contained a very long, much decayed,
worm-shaped animal. Lastly, a seventh bladder contained an organism,
but of what nature could not be distinguished.]

Only one experiment was tried on the quadrifid processes and glands
with reference to their power of absorption. A bladder was punctured
and left for 24 hrs. in a solution of one part of urea to 437 of water,
and the quadrifid and bifid processes were found much affected. In some
arms there was only a single symmetrical globular mass, larger than the
proper nucleus, and consisting of yellowish matter, generally
translucent but sometimes granular; in others there were two masses of
different sizes, one large and the [page 438] other small; and in
others there were irregularly shaped globules; so that it appeared as
if the limpid contents of the processes, owing to the absorption of
matter from the solution, had become aggregated sometimes round the
nucleus, and sometimes into separate masses; and that these then tended
to coalesce. The primordial utricle or protoplasm lining the processes
was also thickened here and there into irregular and variously shaped
specks of yellowish translucent matter, as occurred in the case of
Utricularia neglecta under similar treatment.  These specks apparently
did not change their forms.

The minute two-armed glands on the valve were also affected by the
solution; for they now contained several, sometimes as many as six or
eight, almost spherical masses of translucent matter, tinged with
yellow, which slowly changed their forms and positions. Such masses
were never observed in these glands in their ordinary state. We may
therefore infer that they serve for absorption. Whenever a little water
is expelled from a bladder containing animal remains (by the means
formerly specified, more especially by the generation of bubbles of
air), it will fill the cavity in which the valve lies; and thus the
glands will be able to utilise decayed matter which otherwise would
have been wasted.

Finally, as numerous minute animals are captured by this plant in its
native country and when cultivated, there can be no doubt that the
bladders, though so small, are far from being in a rudimentary
condition; on the contrary, they are highly efficient traps. Nor can
there be any doubt that matter is absorbed from the decayed prey by the
quadrifid and bifid processes, and that protoplasm is thus generated.
What tempts animals of such diverse kinds to enter [page 439] the
cavity beneath the bowed antennae, and then force their way through the
little slit-like orifice between the valve and collar into the bladders
filled with water, I cannot conjecture.

Tubers.--These organs, one of which is represented in a previous figure
(fig. 26) of the natural size, deserve a few remarks. Twenty were found
on the rhizomes of a single plant, but they cannot be strictly counted;
for, besides the twenty, there were all possible gradations between a
short length of a rhizome just perceptibly swollen and one so much
swollen that it might be doubtfully called a tuber. When well
developed, they are oval and symmetrical, more so than appears in the
figure. The largest which I saw was 1 inch (25.4 mm.) in length and .45
inch (11.43 mm.) in breadth. They commonly lie near the surface, but
some are buried at the depth of 2 inches. The buried ones are dirty
white, but those partly exposed to the light become greenish from the
development, of chlorophyll in their superficial cells.  They terminate
in a rhizome, but this sometimes decays and drops off . They do not
contain any air, and they sink in water; their surfaces are covered
with the usual papillae. The bundle of vessels which runs up each
rhizome, as soon as it enters the tuber, separates into three distinct
bundles, which reunite at the opposite end. A rather thick slice of a
tuber is almost as translucent as glass, and is seen to consist of
large angular cells, full of water and not containing starch or any
other solid matter. Some slices were left in alcohol for several days,
but only a few extremely minute granules of matter were precipitated on
the walls of the cells; and these were much smaller and fewer than
those precipitated on the cell-walls of the rhizomes and bladders. We
may therefore con- [page 440] clude that the tuber do not serve as
reservoirs for food, but for water during the dry season to which the
plant is probably exposed. The many little bladders filled with water
would aid towards the same end.

To test the correctness of this view, a small plant, growing in light
peaty earth in a pot (only 4 1/2 by 4 1/2 inches outside measure) was
copiously watered, and then kept without a drop of water in the
hothouse. Two of the upper tubers were beforehand uncovered and
measured, and then loosely covered up again. In a fortnight's time the
earth in the pot appeared extremely dry; but not until the thirty-fifth
day were the leaves in the least affected; they then became slightly
reflexed, though still soft and green. This plant, which bore only ten
tubers, would no doubt have resisted the drought for even a longer
time, had I not previously removed three of the tubers and cut off
several long rhizomes. When, on the thirty-fifth day, the earth in the
pot was turned out, it appeared as dry as the dust on a road. All the
tubers had their surfaces much wrinkled, instead of being smooth and
tense. They had all shrunk, but I cannot say accurately how much; for
as they were at first symmetrically oval, I measured only their length
and thickness; but they contracted in a transverse line much more in
one direction than in another, so as to become greatly flattened. One
of the two tubers which had been measured was now three-fourths of its
original length, and two-thirds of its original thickness in the
direction in which it had been measured, but in another direction only
one- third of its former thickness. The other tuber was one-fourth
shorter, one-eighth less thick in the direction in which it had been
measured, and only half as thick in another direction.

A slice was cut from one of these shrivelled tubers [page 441] and
examined. The cells still contained much water and no air, but they
were more rounded or less angular than before, and their walls not
nearly so straight; it was therefore clear that the cells had
contracted. The tubers, as long as they remain alive, have a strong
attraction for water; the shrivelled one, from which a slice had been
cut, was left in water for 22 hrs. 30 m., and its surface became as
smooth and tense as it originally was. On the other hand, a shrivelled
tuber, which by some accident had been separated from its rhizome, and
which appeared dead, did not swell in the least, though left for
several days in water.

With many kinds of plants, tubers, bulbs, &c. no doubt serve in part as
reservoirs for water, but I know of no case, besides the present one,
of such organs having been developed solely for this purpose. Prof.
Oliver informs me that two or three species of Utricularia are provided
with these appendages; and the group containing them has in consequence
received the name of orchidioides. All the other species of
Utricularia, as well as of certain closely related genera, are either
aquatic or marsh plants; therefore, on the principle of nearly allied
plants generally having a similar constitution, a never failing supply
of water would probably be of great importance to our present species.
We can thus understand the meaning of the development of its tubers,
and of their number on the same plant, amounting in one instance to at
least twenty.

  UTRICULARIA NELUMBIFOLIA, AMETHYSTINA, GRIFFITHII, CAERULEA,
                   ORBICULATA, MULTICAULIS.

As I wished to ascertain whether the bladders on the rhizomes of other
species of Utricularia, and of the [page 442] species of certain
closely allied genera, had the same essential structure as those of
Utricularia montana, and whether they captured prey, I asked Prof.
Oliver to send me fragments from the herbarium at Kew. He kindly
selected some of the most distinct forms, having entire leaves, and
believed to inhabit marshy ground or water. My son Francis Darwin,
examined them, and has given me the following observations; but it
should be borne in mind that it is extremely difficult to make out the
structure of such minute and delicate objects after they have been
dried and pressed.*

Utricularia nelumbifolia (Organ Mountains, Brazil).--The habitat of
this species is remarkable. According to its discoverer, Mr. Gardner,
it is aquatic, but "is only to be found growing in the water which
collects in the bottom of the leaves of a large Tillandsia, that
inhabits abundantly an arid rocky part of the mountain, at an elevation
of about 5000 feet above the level of the sea. Besides the ordinary
method by seed, it propagates itself by runners, which it throws out
from the base of the flower-stem; this runner is always found directing
itself towards the nearest Tillandsia, when it inserts its point into
the water and gives origin to a new plant, which in its turn sends out
another shoot. In this manner I have seen not less than six plants
united." The bladders resemble those of Utricularia montana in all
essential respects, even to the presence of a few minute two-armed
glands on the valve.  Within one bladder there was the remnant of the
abdomen of some larva or crustacean of large size,

* Prof. Oliver has given ('Proc. Linn. Soc.' vol. iv. p. 169) figures
of the bladders of two South American species, namely Utricularia
Jamesoniana and peltata; but he does not appear to have paid particular
attention to these organs.

  'Travels in the Interior of Brazil, 1836-41,' p. 527.  [page 443]

having a brush of long sharp bristles at the apex. Other bladders
included fragments of articulate animals, and many of them contained
broken pieces of a curious organism, the nature of which was not
recognised by anyone to whom it was shown.

Utricularia amethystina (Guiana).--This species has small entire
leaves, and is apparently a marsh plant; but it must grow in places
where crustaceans exist, for there were two small species within one of
the bladders. The bladders are nearly of the same shape as those of
Utricularia montana, and are covered outside with the usual papillae;
but they differ remarkably in the antennae being reduced to two short
points, united by a membrane hollowed out in the middle. This membrane
is covered with innumerable oblong glands supported on long footstalks;
most of which are arranged in two rows converging towards the valve.
Some, however, are seated on the margins of the membrane; and the short
ventral surface of the bladder, between the petiole and valve, is
thickly covered with glands. Most of the heads had fallen off, and the
footstalks alone remained; so that the ventral surface and the orifice,
when viewed under a weak power, appeared as if clothed with fine
bristles. The valve is narrow, and bears a few almost sessile glands.
The collar against which the edge shuts is yellowish, and presents the
usual structure. From the large number of glands on the ventral surface
and round the orifice, it is probable that this species lives in very
foul water, from which it absorbs matter, as well as from its captured
and decaying prey.

Utricularia griffithii (Malay and Borneo).--The bladders are
transparent and minute; one which was measured being only 28/1000 of an
inch (.711 mm.) in diameter. The antennae are of moderate length, and
[page 444] project straight forward; they are united for a short space
at their bases by a membrane; and they bear a moderate number of
bristles or hairs, not simple as heretofore, but surmounted by glands.
The bladders also differ remarkably from those of the previous species,
as within there are no quadrifid, only bifid, processes. In one bladder
there was a minute aquatic larva; in another the remains of some
articulate animal; and in most of them grains of sand.

Utricularia caerulea (India).--The bladders resemble those of the last
species, both in the general character of the antennae and in the
processes within being exclusively bifid. They contained remnants of
entomostracan crustaceans.

Utricularia orbiculata (India).--The orbicular leaves and the stems
bearing the bladders apparently float in water. The bladders do not
differ much from those of the two last species.  The antennae, which
are united for a short distance at their bases, bear on their outer
surfaces and summits numerous, long, multicellular hairs, surmounted by
glands. The processes within the bladders are quadrifid, with the four
diverging arms of equal length. The prey which they had captured
consisted of entomostracan crustaceans.

Utricularia multicaulis (Sikkim, India, 7000 to 11,000 feet).--The
bladders, attached to rhizomes, are remarkable from the structure of
the antennae. These are broad, flattened, and of large size; they bear
on their margins multicellular hairs, surmounted by glands. Their bases
are united into a single, rather narrow pedicel, and they thus appear
like a great digitate expansion at one end of the bladder. Internally
the quadrifid processes have divergent arms of equal length. The
bladders contained remnants of articulate animals.  [page 445]

                        POLYPOMPHOLYX.

This genus, which is confined to Western Australia, is characterised by
having a "quadripartite calyx." In other respects, as Prof. Oliver
remarks,* "it is quite a Utricularia."

Polypompholyx multifida.--The bladders are attached in whorls round the
summits of stiff stalks. The two antennae are represented by a minute
membranous fork, the basal part of which forms a sort of hood over the
orifice. This hood expands into two wings on each side of the bladder.
A third wing or crest appears to be formed by the extension of the
dorsal surface of the petiole; but the structure of these three wings
could not be clearly made out, owing to the state of the specimens. The
inner surface of the hood is lined with long simple hairs, containing
aggregated matter, like that within the quadrifid processes of the
previously described species when in contact with decayed animals.
These hairs appear therefore to serve as absorbents. A valve was seen,
but its structure could not be determined. On the collar round the
valve there are in the place of glands numerous one-celled papillae,
having very short footstalks. The quadrifid processes have divergent
arms of equal length. Remains of entomostracan crustaceans were found
within the bladders.

Polypompholyx tenella.--The bladders are smaller than those of the last
species, but have the same general structure. They were full of dbris,
apparently organic, but no remains of articulate animals could be
distinguished.

* 'Proc. Linn. Soc.' vol. iv. p. 171.  [page 446]

                           GENLISEA.

This remarkable genus is technically distinguished from Utricularia, as
I hear from Prof.  Oliver, by having a five-partite calyx. Species are
found in several parts of the world, and are said to be "herbae annuae
paludosae."

Genlisea ornata (Brazil).--This species has been described and figured
by Dr. Warming,* who states that it bears two kinds of leaves, called
by him spathulate and utriculiferous. The latter include cavities; and
as these differ much from the bladders of the foregoing species, it
will be convenient to speak of them as utricles. The accompanying
figure (fig. 29) of one of the utriculiferous leaves, about thrice
enlarged, will illustrate the following description by my son, which
agrees in all essential points with that given by Dr. Warming. The
utricle (b) is formed by a slight enlargement of the narrow blade of
the leaf. A hollow neck (n), no less than fifteen times as long as the
utricle itself, forms a passage from the transverse slit-like orifice
(o) into the cavity of the utricle. A utricle which measured 1/36 of an
inch (.705 mm.,) in its longer diameter had a neck 15/36 (10.583 mm.)
in length, and 1/100 of an inch (.254 mm.) in breadth. On each side of
the orifice there is a long spiral arm or tube (a); the structure of
which will be best understood by the following illustration. Take a
narrow ribbon and wind it spirally round a thin cylinder, so that the
edges come into contact along its whole length; then pinch up the two
edges so as to form a little crest, which will of course wind spirally

* "Bidrag til Kundskaben om Lentibulariaceae," Copenhagen 1874.  [page
447]

round the cylinder like a thread round a screw. If the cylinder is now
removed, we shall have a tube like one of the spiral arms. The two
projecting edges are not actually united, and a needle can be pushed in
easily between them. They are indeed in many places a little separated,
forming narrow entrances into the tube; but this may be the result of
the drying of the specimens. The lamina of which the tube is formed
seems to be a lateral prolongation of the lip of the orifice; and the
spiral line between the two projecting edges is continuous with the
corner of the orifice. If a fine bristle is pushed down one of the
arms, it passes into the top of the hollow neck. Whether the arms are
open or closed at their extremities could not be determined, as all the
specimens were broken; nor does it appear that Dr. Warming ascertained
this point.

FIG. 29.  (Genlisea ornata.) Utriculiferous leaf; enlarged about three
times.  l Upper part of lamina of leaf.  b Utricle or bladder.  n Neck
of utricle.  o Orifice.  a Spirally wound arms, with their ends broken
off.

So much for the external structure. Internally the lower part of the
utricle is covered with spherical papillae, formed of four cells
(sometimes eight according to Dr. Warming), which evidently answer to
the quadrifid processes within the bladders of Utricularia.  [page 448]
These papillae extend a little way up the dorsal and ventral surfaces
of the utricle; and a few, according to Warming, may be found in the
upper part. This upper region is covered by many transverse rows, one
above the other, of short, closely approximate hairs, pointing
downwards. These hairs have broad bases, and their tips are formed by a
separate cell. They are absent in the lower part of the utricle where
the papillae abound.

FIG. 30.  (Genlisea ornata.) Portion of inside of neck leading into the
utricle, greatly enlarged, showing the downward pointed bristles, and
small quadrifid cells or processes.

The neck is likewise lined throughout its whole length with transverse
rows of long, thin, transparent hairs, having broad bulbous (fig. 30)
bases, with similarly constructed sharp points. They arise from little
projecting ridges, formed of rectangular epidermic cells. The hairs
vary a little in length, but their points generally extend down to the
row next below; so that if the neck is split open and laid flat, the
inner surface resembles a paper of pins,--the hairs representing the
pins, and the little transverse ridges representing the folds of paper
through which the pins are thrust. These rows of hairs are indicated in
the previous figure (29) by numerous transverse lines crossing the
neck. The inside of the neck is [page 449] also studded with papillae;
those in the lower part are spherical and formed of four cells, as in
the lower part of the utricle; those in the upper part are formed of
two cells, which are much elongated downwards beneath their points of
attachment. These two-celled papillae apparently correspond with the
bifid process in the upper part of the bladders of Utricularia.  The
narrow transverse orifice (o, fig. 29) is situated between the bases of
the two spiral arms.  No valve could be detected here, nor was any such
structure seen by Dr. Warming. The lips of the orifice are armed with
many short, thick, sharply pointed, somewhat incurved hairs or teeth.

The two projecting edges of the spirally wound lamina, forming the
arms, are provided with short incurved hairs or teeth, exactly like
those on the lips. These project inwards at right angles to the spiral
line of junction between the two edges. The inner surface of the lamina
supports two-celled, elongated papillae, resembling those in the upper
part of the neck, but differing slightly from them, according to
Warming, in their footstalks being formed by prolongations of large
epidermic cells; whereas the papillae within the neck rest on small
cells sunk amidst the larger ones. These spiral arms form a conspicuous
difference between the present genus and Utricularia.

Lastly, there is a bundle of spiral vessels which, running up the lower
part of the linear leaf, divides close beneath the utricle. One branch
extends up the dorsal and the other up the ventral side of both the
utricle and neck. Of these two branches, one enters one spiral arm, and
the other branch the other arm.

The utricles contained much dbris or dirty matter, which seemed
organic, though no distinct organisms [page 450] could be recognised.
It is, indeed, scarcely possible that any object could enter the small
orifice and pass down the long narrow neck, except a living creature.
Within the necks, however, of some specimens, a worm with retracted
horny jaws, the abdomen of some articulate animal, and specks of dirt,
probably the remnants of other minute creatures, were found. Many of
the papillae within both the utricles and necks were discoloured, as if
they had absorbed matter.

From this description it is sufficiently obvious how Genlisea secures
its prey. Small animals entering the narrow orifice--but what induces
them to enter is not known any more than in the case of
Utricularia--would find their egress rendered difficult by the sharp
incurved hairs on the lips, and as soon as they passed some way down
the neck, it would be scarcely possible for them to return, owing to
the many transverse rows of long, straight, downward pointing hairs,
together with the ridges from which these project. Such creatures
would, therefore, perish either within the neck or utricle; and the
quadrifid and bifid papillae would absorb matter from their decayed
remains. The transverse rows of hairs are so numerous that they seem
superfluous merely for the sake of preventing the escape of prey, and
as they are thin and delicate, they probably serve as additional
absorbents, in the same manner as the flexible bristles on the infolded
margins of the leaves of Aldrovanda. The spiral arms no doubt act as
accessory traps. Until fresh leaves are examined, it cannot be told
whether the line of junction of the spirally wound lamina is a little
open along its whole course, or only in parts, but a small creature
which forced its way into the tube at any point, would be prevented
from escaping by the incurved hairs, and would find an open path down
[page 451] the tube into the neck, and so into the utricle. If the
creature perished within the spiral arms, its decaying remains would be
absorbed and utilised by the bifid papillae. We thus see that animals
are captured by Genlisea, not by means of an elastic valve, as with the
foregoing species, but by a contrivance resembling an eel-trap, though
more complex.

Genlisea africana (South Africa).--Fragments of the utriculiferous
leaves of this species exhibited the same structure as those of
Genlisea ornata. A nearly perfect Acarus was found within the utricle
or neck of one leaf, but in which of the two was not recorded.

Genlisea aurea (Brazil).--A fragment of the neck of a utricle was lined
with transverse rows of hairs, and was furnished with elongated
papillae, exactly like those within the neck of Genlisea ornata. It is
probable, therefore, that the whole utricle is similarly constructed.

Genlisea filiformis (Bahia, Brazil).--Many leaves were examined and
none were found provided with utricles, whereas such leaves were found
without difficulty in the three previous species. On the other hand,
the rhizomes bear bladders resembling in essential character those on
the rhizomes of Utricularia. These bladders are transparent, and very
small, viz. Only 1/100 of an inch (.254 mm.) in length. The antennae
are not united at their bases, and apparently bear some long hairs. On
the outside of the bladders there are only a few papillae, and
internally very few quadrifid processes. These latter, however, are of
unusually large size, relatively to the bladder, with the four
divergent arms of equal length.  No prey could be seen within these
minute bladders. As the rhizomes of this species were furnished with
bladders, those of Genlisea africana, ornata, and aurea were carefully
[page 452] examined, but none could be found. What are we to infer from
these facts? Did the three species just named, like their close allies,
the several species of Utricularia, aboriginally possess bladders on
their rhizomes, which they afterwards lost, acquiring in their place
utriculiferous leaves? In support of this view it may be urged that the
bladders of Genlisea filiformis appear from their small size and from
the fewness of their quadrifid processes to be tending towards
abortion; but why has not this species acquired utriculiferous leaves,
like its congeners?

CONCLUSION.--It has now been shown that many species of Utricularia and
of two closely allied genera, inhabiting the most distant parts of the
world--Europe, Africa, India, the Malay Archipelago, Australia, North
and South America--are admirably adapted for capturing by two methods
small aquatic or terrestrial animals, and that they absorb the products
of their decay.

Ordinary plants of the higher classes procure the requisite inorganic
elements from the soil by means of their roots, and absorb carbonic
acid from the atmosphere by means of their leaves and stems. But we
have seen in a previous part of this work that there is a class of
plants which digest and afterwards absorb animal matter, namely, all
the Droseraceae, Pinguicula, and, as discovered by Dr. Hooker,
Nepenthes, and to this class other species will almost certainly soon
be added. These plants can dissolve matter out of certain vegetable
substances, such as pollen, seeds, and bits of leaves. No doubt their
glands likewise absorb the salts of ammonia brought to them by the
rain. It has also been shown that some other plants can absorb ammonia
by [page 453] their glandular hairs; and these will profit by that
brought to them by the rain. There is a second class of plants which,
as we have just seen, cannot digest, but absorb the products of the
decay of the animals which they capture, namely, Utricularia and its
close allies; and from the excellent observations of Dr. Mellichamp and
Dr. Canby, there can scarcely be a doubt that Sarracenia and
Darlingtonia may be added to this class, though the fact can hardly be
considered as yet fully proved. There is a third class of plants which
feed, as is now generally admitted, on the products of the decay of
vegetable matter, such as the bird's-nest orchis (Neottia), &c. Lastly,
there is the well-known fourth class of parasites (such as the
mistletoe), which are nourished by the juices of living plants. Most,
however, of the plants belonging to these four classes obtain part of
their carbon, like ordinary species, from the atmosphere. Such are the
diversified means, as far as at present known, by which higher plants
gain their subsistence.
WHEN we look to the individuals of the same variety or sub-variety of our older cultivated plants and animals, one of the first points which strikes us, is, that they generally differ much more from each other, than do the individuals of any one species or variety in a state of nature. When we reflect on the vast diversity of the plants and animals which have been cultivated, and which have varied during all ages under the most different climates and treatment, I think we are driven to conclude that this greater variability is simply due to our domestic productions having been raised under conditions of life not so uniform as, and somewhat different from, those to which the parent-species have been exposed under nature. There is, also, I think, some probability in the view propounded by Andrew Knight, that this variability may be partly connected with excess of food. It seems pretty clear that organic beings must be exposed during several generations to the new conditions of life to cause any appreciable amount of variation; and that when the organisation has once begun to vary, it generally continues to vary for many generations. No case is on record of a variable being ceasing to be variable under cultivation. Our oldest cultivated plants, such as wheat, still often yield new varieties: our oldest domesticated animals are still capable of rapid improvement or modification. 

It has been disputed at what period of time the causes of variability, whatever they may be, generally act; whether during the early or late period of development of the embryo, or at the instant of conception. Geoffroy St Hilaire's experiments show that unnatural treatment of the embryo causes monstrosities; and monstrosities cannot be separated by any clear line of distinction from mere variations. But I am strongly inclined to suspect that the most frequent cause of variability may be attributed to the male and female reproductive elements having been affected prior to the act of conception. Several reasons make me believe in this; but the chief one is the remarkable effect which confinement or cultivation has on the functions of the reproductive system; this system appearing to be far more susceptible than any other part of the organization, to the action of any change in the conditions of life. Nothing is more easy than to tame an animal, and few things more difficult than to get it to breed freely under confinement, even in the many cases when the male and female unite. How many animals there are which will not breed, though living long under not very close confinement in their native country! This is generally attributed to vitiated instincts; but how many cultivated plants display the utmost vigour, and yet rarely or never seed! In some few such cases it has been found out that very trifling changes, such as a little more or less water at some particular period of growth, will determine whether or not the plant sets a seed. I cannot here enter on the copious details which I have collected on this curious subject; but to show how singular the laws are which determine the reproduction of animals under confinement, I may just mention that carnivorous animals, even from the tropics, breed in this country pretty freely under confinement, with the exception of the plantigrades or bear family; whereas, carnivorous birds, with the rarest exceptions, hardly ever lay fertile eggs. Many exotic plants have pollen utterly worthless, in the same exact condition as in the most sterile hybrids. When, on the one hand, we see domesticated animals and plants, though often weak and sickly, yet breeding quite freely under confinement; and when, on the other hand, we see individuals, though taken young from a state of nature, perfectly tamed, long-lived, and healthy (of which I could give numerous instances), yet having their reproductive system so seriously affected by unperceived causes as to fail in acting, we need not be surprised at this system, when it does act under confinement, acting not quite regularly, and producing offspring not perfectly like their parents or variable. 

Sterility has been said to be the bane of horticulture; but on this view we owe variability to the same cause which produces sterility; and variability is the source of all the choicest productions of the garden. I may add, that as some organisms will breed most freely under the most unnatural conditions (for instance, the rabbit and ferret kept in hutches), showing that their reproductive system has not been thus affected; so will some animals and plants withstand domestication or cultivation, and vary very slightly perhaps hardly more than in a state of nature. 

A long list could easily be given of 'sporting plants;' by this term gardeners mean a single bud or offset, which suddenly assumes a new and sometimes very different character from that of the rest of the plant. Such buds can be propagated by grafting, &c., and sometimes by seed. These 'sports' are extremely rare under nature, but far from rare under cultivation; and in this case we see that the treatment of the parent has affected a bud or offset, and not the ovules or pollen. But it is the opinion of most physiologists that there is no essential difference between a bud and an ovule in their earliest stages of formation; so that, in fact,'sports' support my view, that variability may be largely attributed to the ovules or pollen, or to both, having been affected by the treatment of the parent prior to the act of conception. These cases anyhow show that variation is not necessarily connected, as some authors have supposed, with the act of generation. 

Seedlings from the same fruit, and the young of the same litter, sometimes differ considerably from each other, though both the young and the parents, as Muller has remarked, have apparently been exposed to exactly the same conditions of life; and this shows how unimportant the direct effects of the conditions of life are in comparison with the laws of reproduction, and of growth, and of inheritance; for had the action of the conditions been direct, if any of the young had varied, all would probably have varied in the same manner. To judge how much, in the case of any variation, we should attribute to the direct action of heat, moisture, light, food, &c., is most difficult: my impression is, that with animals such agencies have produced very little direct effect, though apparently more in the case of plants. Under this point of view, Mr Buckman's recent experiments on plants seem extremely valuable. When all or nearly all the individuals exposed to certain conditions are affected in the same way, the change at first appears to be directly due to such conditions; but in some cases it can be shown that quite opposite conditions produce similar changes of structure. Nevertheless some slight amount of change may, I think, be attributed to the direct action of the conditions of life as, in some cases, increased size from amount of food, colour from particular kinds of food and from light, and perhaps the thickness of fur from climate. 

Habit also has a deciding influence, as in the period of flowering with plants when transported from one climate to another. In animals it has a more marked effect; for instance, I find in the domestic duck that the bones of the wing weigh less and the bones of the leg more, in proportion to the whole skeleton, than do the same bones in the wild-duck; and I presume that this change may be safely attributed to the domestic duck flying much less, and walking more, than its wild parent. The great and inherited development of the udders in cows and goats in countries where they are habitually milked, in comparison with the state of these organs in other countries, is another instance of the effect of use. Not a single domestic animal can be named which has not in some country drooping ears; and the view suggested by some authors, that the drooping is due to the disuse of the muscles of the ear, from the animals not being much alarmed by danger, seems probable. 

There are many laws regulating variation, some few of which can be dimly seen, and will be hereafter briefly mentioned. I will here only allude to what may be called correlation of growth. Any change in the embryo or larva will almost certainly entail changes in the mature animal. In monstrosities, the correlations between quite distinct parts are very curious; and many instances are given in Isidore Geoffroy St Hilaire's great work on this subject. Breeders believe that long limbs are almost always accompanied by an elongated head. Some instances of correlation are quite whimsical; thus cats with blue eyes are invariably deaf; colour and constitutional peculiarities go together, of which many remarkable cases could be given amongst animals and plants. From the facts collected by Heusinger, it appears that white sheep and pigs are differently affected from coloured individuals by certain vegetable poisons. Hairless dogs have imperfect teeth; long-haired and coarse-haired animals are apt to have, as is asserted, long or many horns; pigeons with feathered feet have skin between their outer toes; pigeons with short beaks have small feet, and those with long beaks large feet. Hence, if man goes on selecting, and thus augmenting, any peculiarity, he will almost certainly unconsciously modify other parts of the structure, owing to the mysterious laws of the correlation of growth. 

The result of the various, quite unknown, or dimly seen laws of variation is infinitely complex and diversified. It is well worth while carefully to study the several treatises published on some of our old cultivated plants, as on the hyacinth, potato, even the dahlia, &c.; and it is really surprising to note the endless points in structure and constitution in which the varieties and sub varieties differ slightly from each other. The whole organization seems to have become plastic, and tends to depart in some small degree from that of the parental type. 

Any variation which is not inherited is unimportant for us. But the number and diversity of inheritable deviations of structure, both those of slight and those of considerable physiological importance, is endless. Dr Prosper Lucas's treatise, in two large volumes, is the fullest and the best on this subject. No breeder doubts how strong is the tendency to inheritance: like produces like is his fundamental belief: doubts have been thrown on this principle by theoretical writers alone. When a deviation appears not unfrequently, and we see it in the father and child, we cannot tell whether it may not be due to the same original cause acting on both; but when amongst individuals, apparently exposed to the same conditions, any very rare deviation, due to some extraordinary combination of circumstances, appears in the parent say, once amongst several million individuals and it reappears in the child, the mere doctrine of chances almost compels us to attribute its reappearance to inheritance. Every one must have heard of cases of albinism, prickly skin, hairy bodies, &c. appearing in several members of the same family. If strange and rare deviations of structure are truly inherited, less strange and commoner deviations may be freely admitted to be inheritable. Perhaps the correct way of viewing the whole subject, would be, to look at the inheritance of every character whatever as the rule, and non-inheritance as the anomaly. 

The laws governing inheritance are quite unknown; no one can say why the same peculiarity in different individuals of the same species, and in individuals of different species, is sometimes inherited and sometimes not so; why the child often reverts in certain characters to its grandfather or grandmother or other much more remote ancestor; why a peculiarity is often transmitted from one sex to both sexes or to one sex alone, more commonly but not exclusively to the like sex. It is a fact of some little importance to us, that peculiarities appearing in the males of our domestic breeds are often transmitted either exclusively, or in a much greater degree, to males alone. A much more important rule, which I think may be trusted, is that, at whatever period of life a peculiarity first appears, it tends to appear in the offspring at a corresponding age, though sometimes earlier. In many cases this could not be otherwise: thus the inherited peculiarities in the horns of cattle could appear only in the offspring when nearly mature; peculiarities in the silkworm are known to appear at the corresponding caterpillar or cocoon stage. But hereditary diseases and some other facts make me believe that the rule has a wider extension, and that when there is no apparent reason why a peculiarity should appear at any particular age, yet that it does tend to appear in the offspring at the same period at which it first appeared in the parent. I believe this rule to be of the highest importance in explaining the laws of embryology. These remarks are of course confined to the first appearance of the peculiarity, and not to its primary cause, which may have acted on the ovules or male element; in nearly the same manner as in the crossed offspring from a short-horned cow by a long-horned bull, the greater length of horn, though appearing late in life, is clearly due to the male element. 

Having alluded to the subject of reversion, I may here refer to a statement often made by naturalists namely, that our domestic varieties, when run wild, gradually but certainly revert in character to their aboriginal stocks. Hence it has been argued that no deductions can be drawn from domestic races to species in a state of nature. I have in vain endeavoured to discover on what decisive facts the above statement has so often and so boldly been made. There would be great difficulty in proving its truth: we may safely conclude that very many of the most strongly-marked domestic varieties could not possibly live in a wild state. In many cases we do not know what the aboriginal stock was, and so could not tell whether or not nearly perfect reversion had ensued. It would be quite necessary, in order to prevent the effects of intercrossing, that only a single variety should be turned loose in its new home. Nevertheless, as our varieties certainly do occasionally revert in some of their characters to ancestral forms, it seems to me not improbable, that if we could succeed in naturalising, or were to cultivate, during many generations, the several races, for instance, of the cabbage, in very poor soil (in which case, however, some effect would have to be attributed to the direct action of the poor soil), that they would to a large extent, or even wholly, revert to the wild aboriginal stock. Whether or not the experiment would succeed, is not of great importance for our line of argument; for by the experiment itself the conditions of life are changed. If it could be shown that our domestic varieties manifested a strong tendency to reversion, that is, to lose their acquired characters, whilst kept under unchanged conditions, and whilst kept in a considerable body, so that free intercrossing might check, by blending together, any slight deviations of structure, in such case, I grant that we could deduce nothing from domestic varieties in regard to species. But there is not a shadow of evidence in favour of this view: to assert that we could not breed our cart and race-horses, long and short-horned cattle and poultry of various breeds, and esculent vegetables, for an almost infinite number of generations, would be opposed to all experience. I may add, that when under nature the conditions of life do change, variations and reversions of character probably do occur; but natural selection, as will hereafter be explained, will determine how far the new characters thus arising shall be preserved. 

When we look to the hereditary varieties or races of our domestic animals and plants, and compare them with species closely allied together, we generally perceive in each domestic race, as already remarked, less uniformity of character than in true species. Domestic races of the same species, also, often have a somewhat monstrous character; by which I mean, that, although differing from each other, and from the other species of the same genus, in several trifling respects, they often differ in an extreme degree in some one part, both when compared one with another, and more especially when compared with all the species in nature to which they are nearest allied. With these exceptions (and with that of the perfect fertility of varieties when crossed, a subject hereafter to be discussed), domestic races of the same species differ from each other in the same manner as, only in most cases in a lesser degree than, do closely-allied species of the same genus in a state of nature. I think this must be admitted, when we find that there are hardly any domestic races, either amongst animals or plants, which have not been ranked by some competent judges as mere varieties, and by other competent judges as the descendants of aboriginally distinct species. If any marked distinction existed between domestic races and species, this source of doubt could not so perpetually recur. It has often been stated that domestic races do not differ from each other in characters of generic value. I think it could be shown that this statement is hardly correct; but naturalists differ most widely in determining what characters are of generic value; all such valuations being at present empirical. Moreover, on the view of the origin of genera which I shall presently give, we have no right to expect often to meet with generic differences in our domesticated productions. 

When we attempt to estimate the amount of structural difference between the domestic races of the same species, we are soon involved in doubt, from not knowing whether they have descended from one or several parent-species. This point, if could be cleared up, would be interesting; if, for instance, it could be shown that the greyhound, bloodhound, terrier, spaniel, and bull-dog, which we all know propagate their kind so truly, were the offspring of any single species, then such facts would have great weight in making us doubt about the immutability of the many very closely allied and natural species for instance, of the many foxes inhabiting different quarters of the world. I do not believe, as we shall presently see, that all our dogs have descended from any one wild species; but, in the case of some other domestic races, there is presumptive, or even strong, evidence in favour of this view. 

It has often been assumed that man has chosen for domestication animals and plants having an extraordinary inherent tendency to vary, and likewise to withstand diverse climates. I do not dispute that these capacities have added largely to the value of most of our domesticated productions; but how could a savage possibly know, when he first tamed an animal, whether it would vary in succeeding generations, and whether it would endure other climates? Has the little variability of the ass or guinea-fowl, or the small power of endurance of warmth by the reindeer, or of cold by the common camel, prevented their domestication? I cannot doubt that if other animals and plants, equal in number to our domesticated productions, and belonging to equally diverse classes and countries, were taken from a state of nature, and could be made to breed for an equal number of generations under domestication, they would vary on an average as largely as the parent species of our existing domesticated productions have varied. 

In the case of most of our anciently domesticated animals and plants, I do not think it is possible to come to any definite conclusion, whether they have descended from one or several species. The argument mainly relied on by those who believe in the multiple origin of our domestic animals is, that we find in the most ancient records, more especially on the monuments of Egypt, much diversity in the breeds; and that some of the breeds closely resemble, perhaps are identical with, those still existing. Even if this latter fact were found more strictly and generally true than seems to me to be the case, what does it show, but that some of our breeds originated there, four or five thousand years ago? But Mr Horner's researches have rendered it in some degree probable that man sufficiently civilized to have manufactured pottery existed in the valley of the Nile thirteen or fourteen thousand years ago; and who will pretend to say how long before these ancient periods, savages, like those of Tierra del Fuego or Australia, who possess a semi-domestic dog, may not have existed in Egypt? 

The whole subject must, I think, remain vague; nevertheless, I may, without here entering on any details, state that, from geographical and other considerations, I think it highly probable that our domestic dogs have descended from several wild species. In regard to sheep and goats I can form no opinion. I should think, from facts communicated to me by Mr Blyth, on the habits, voice, and constitution, &c., of the humped Indian cattle, that these had descended from a different aboriginal stock from our European cattle; and several competent judges believe that these latter have had more than one wild parent. With respect to horses, from reasons which I cannot give here, I am doubtfully inclined to believe, in opposition to several authors, that all the races have descended from one wild stock. Mr Blyth, whose opinion, from his large and varied stores of knowledge, I should value more than that of almost any one, thinks that all the breeds of poultry have proceeded from the common wild Indian fowl (Gallus bankiva). In regard to ducks and rabbits, the breeds of which differ considerably from each other in structure, I do not doubt that they all have descended from the common wild duck and rabbit. 

The doctrine of the origin of our several domestic races from several aboriginal stocks, has been carried to an absurd extreme by some authors. They believe that every race which breeds true, let the distinctive characters be ever so slight, has had its wild prototype. At this rate there must have existed at least a score of species of wild cattle, as many sheep, and several goats in Europe alone, and several even within Great Britain. One author believes that there formerly existed in Great Britain eleven wild species of sheep peculiar to it! When we bear in mind that Britain has now hardly one peculiar mammal, and France but few distinct from those of Germany and conversely, and so with Hungary, Spain, &c., but that each of these kingdoms possesses several peculiar breeds of cattle, sheep, &c., we must admit that many domestic breeds have originated in Europe; for whence could they have been derived, as these several countries do not possess a number of peculiar species as distinct parent-stocks? So it is in India. Even in the case of the domestic dogs of the whole world, which I fully admit have probably descended from several wild species, I cannot doubt that there has been an immense amount of inherited variation. Who can believe that animals closely resembling the Italian greyhound, the bloodhound, the bull-dog, or Blenheim spaniel, &c. so unlike all wild Canidae ever existed freely in a state of nature? It has often been loosely said that all our races of dogs have been produced by the crossing of a few aboriginal species; but by crossing we can get only forms in some degree intermediate between their parents; and if we account for our several domestic races by this process, we must admit the former existence of the most extreme forms, as the Italian greyhound, bloodhound, bull-dog, &c., in the wild state. Moreover, the possibility of making distinct races by crossing has been greatly exaggerated. There can be no doubt that a race may be modified by occasional crosses, if aided by the careful selection of those individual mongrels, which present any desired character; but that a race could be obtained nearly intermediate between two extremely different races or species, I can hardly believe. Sir J. Sebright expressly experimentised for this object, and failed. The offspring from the first cross between two pure breeds is tolerably and sometimes (as I have found with pigeons) extremely uniform, and everything seems simple enough; but when these mongrels are crossed one with another for several generations, hardly two of them will be alike, and then the extreme difficulty, or rather utter hopelessness, of the task becomes apparent. Certainly, a breed intermediate between two very distinct breeds could not be got without extreme care and long-continued selection; nor can I find a single case on record of a permanent race having been thus formed. 


On the Breeds of the Domestic pigeon.
Believing that it is always best to study some special group, I have, after deliberation, taken up domestic pigeons. I have kept every breed which I could purchase or obtain, and have been most kindly favoured with skins from several quarters of the world, more especially by the Hon. W. Elliot from India, and by the Hon. C. Murray from Persia. Many treatises in different languages have been published on pigeons, and some of them are very important, as being of considerably antiquity. I have associated with several eminent fanciers, and have been permitted to join two of the London Pigeon Clubs. The diversity of the breeds is something astonishing. Compare the English carrier and the short-faced tumbler, and see the wonderful difference in their beaks, entailing corresponding differences in their skulls. The carrier, more especially the male bird, is also remarkable from the wonderful development of the carunculated skin about the head, and this is accompanied by greatly elongated eyelids, very large external orifices to the nostrils, and a wide gape of mouth. The short-faced tumbler has a beak in outline almost like that of a finch; and the common tumbler has the singular and strictly inherited habit of flying at a great height in a compact flock, and tumbling in the air head over heels. The runt is a bird of great size, with long, massive beak and large feet; some of the sub-breeds of runts have very long necks, others very long wings and tails, others singularly short tails. The barb is allied to the carrier, but, instead of a very long beak, has a very short and very broad one. The pouter has a much elongated body, wings, and legs; and its enormously developed crop, which it glories in inflating, may well excite astonishment and even laughter. The turbit has a very short and conical beak, with a line of reversed feathers down the breast; and it has the habit of continually expanding slightly the upper part of the oesophagus. The Jacobin has the feathers so much reversed along the back of the neck that they form a hood, and it has, proportionally to its size, much elongated wing and tail feathers. The trumpeter and laugher, as their names express, utter a very different coo from the other breeds. The fantail has thirty or even forty tail-feathers, instead of twelve or fourteen, the normal number in all members of the great pigeon family; and these feathers are kept expanded, and are carried so erect that in good birds the head and tail touch; the oil-gland is quite aborted. Several other less distinct breeds might have been specified. 

In the skeletons of the several breeds, the development of the bones of the face in length and breadth and curvature differs enormously. The shape, as well as the breadth and length of the ramus of the lower jaw, varies in a highly remarkable manner. The number of the caudal and sacral vertebrae vary; as does the number of the ribs, together with their relative breadth and the presence of processes. The size and shape of the apertures in the sternum are highly variable; so is the degree of divergence and relative size of the two arms of the furcula. The proportional width of the gape of mouth, the proportional length of the eyelids, of the orifice of the nostrils, of the tongue (not always in strict correlation with the length of beak), the size of the crop and of the upper part of the oesophagus; the development and abortion of the oil-gland; the number of the primary wing and caudal feathers; the relative length of wing and tail to each other and to the body; the relative length of leg and of the feet; the number of scutellae on the toes, the development of skin between the toes, are all points of structure which are variable. The period at which the perfect plumage is acquired varies, as does the state of the down with which the nestling birds are clothed when hatched. The shape and size of the eggs vary. The manner of flight differs remarkably; as does in some breeds the voice and disposition. Lastly, in certain breeds, the males and females have come to differ to a slight degree from each other. 

Altogether at least a score of pigeons might be chosen, which if shown to an ornithologist, and he were told that they were wild birds, would certainly, I think, be ranked by him as well-defined species. Moreover, I do not believe that any ornithologist would place the English carrier, the short-faced tumbler, the runt, the barb, pouter, and fantail in the same genus; more especially as in each of these breeds several truly-inherited sub-breeds, or species as he might have called them, could be shown him. 

Great as the differences are between the breeds of pigeons, I am fully convinced that the common opinion of naturalists is correct, namely, that all have descended from the rock-pigeon (Columba livia), including under this term several geographical races or sub-species, which differ from each other in the most trifling respects. As several of the reasons which have led me to this belief are in some degree applicable in other cases, I will here briefly give them. If the several breeds are not varieties, and have not proceeded from the rock-pigeon, they must have descended from at least seven or eight aboriginal stocks; for it is impossible to make the present domestic breeds by the crossing of any lesser number: how, for instance, could a pouter be produced by crossing two breeds unless one of the parent-stocks possessed the characteristic enormous crop? The supposed aboriginal stocks must all have been rock-pigeons, that is, not breeding or willingly perching on trees. But besides C. livia, with its geographical sub-species, only two or three other species of rock-pigeons are known; and these have not any of the characters of the domestic breeds. Hence the supposed aboriginal stocks must either still exist in the countries where they were originally domesticated, and yet be unknown to ornithologists; and this, considering their size, habits, and remarkable characters, seems very improbable; or they must have become extinct in the wild state. But birds breeding on precipices, and good fliers, are unlikely to be exterminated; and the common rock-pigeon, which has the same habits with the domestic breeds, has not been exterminated even on several of the smaller British islets, or on the shores of the Mediterranean. Hence the supposed extermination of so many species having similar habits with the rock-pigeon seems to me a very rash assumption. Moreover, the several above-named domesticated breeds have been transported to all parts of the world, and, therefore, some of them must have been carried back again into their native country; but not one has ever become wild or feral, though the dovecot-pigeon, which is the rock-pigeon in a very slightly altered state, has become feral in several places. Again, all recent experience shows that it is most difficult to get any wild animal to breed freely under domestication; yet on the hypothesis of the multiple origin of our pigeons, it must be assumed that at least seven or eight species were so thoroughly domesticated in ancient times by half-civilized man, as to be quite prolific under confinement. 

An argument, as it seems to me, of great weight, and applicable in several other cases, is, that the above-specified breeds, though agreeing generally in constitution, habits, voice, colouring, and in most parts of their structure, with the wild rock-pigeon, yet are certainly highly abnormal in other parts of their structure: we may look in vain throughout the whole great family of Columbidae for a beak like that of the English carrier, or that of the short-faced tumbler, or barb; for reversed feathers like those of the jacobin; for a crop like that of the pouter; for tail-feathers like those of the fantail. Hence it must be assumed not only that half-civilized man succeeded in thoroughly domesticating several species, but that he intentionally or by chance picked out extraordinarily abnormal species; and further, that these very species have since all become extinct or unknown. So many strange contingencies seem to me improbable in the highest degree. 

Some facts in regard to the colouring of pigeons well deserve consideration. The rock-pigeon is of a slaty-blue, and has a white rump (the Indian sub-species, C. intermedia of Strickland, having it bluish); the tail has a terminal dark bar, with the bases of the outer feathers externally edged with white; the wings have two black bars: some semi-domestic breeds and some apparently truly wild breeds have, besides the two black bars, the wings chequered with black. These several marks do not occur together in any other species of the whole family. Now, in every one of the domestic breeds, taking thoroughly well-bred birds, all the above marks, even to the white edging of the outer tail-feathers, sometimes concur perfectly developed. Moreover, when two birds belonging to two distinct breeds are crossed, neither of which is blue or has any of the above-specified marks, the mongrel offspring are very apt suddenly to acquire these characters; for instance, I crossed some uniformly white fantails with some uniformly black barbs, and they produced mottled brown and black birds; these I again crossed together, and one grandchild of the pure white fantail and pure black barb was of as beautiful a blue colour, with the white rump, double black wing-bar, and barred and white-edged tail-feathers, as any wild rock-pigeon! We can understand these facts, on the well-known principle of reversion to ancestral characters, if all the domestic breeds have descended from the rock-pigeon. But if we deny this, we must make one of the two following highly improbable suppositions. Either, firstly, that all the several imagined aboriginal stocks were coloured and marked like the rock-pigeon, although no other existing species is thus coloured and marked, so that in each separate breed there might be a tendency to revert to the very same colours and markings. Or, secondly, that each breed, even the purest, has within a dozen or, at most, within a score of generations, been crossed by the rock-pigeon: I say within a dozen or twenty generations, for we know of no fact countenancing the belief that the child ever reverts to some one ancestor, removed by a greater number of generations. In a breed which has been crossed only once with some distinct breed, the tendency to reversion to any character derived from such cross will naturally become less and less, as in each succeeding generation there will be less of the foreign blood; but when there has been no cross with a distinct breed, and there is a tendency in both parents to revert to a character, which has been lost during some former generation, this tendency, for all that we can see to the contrary, may be transmitted undiminished for an indefinite number of generations. These two distinct cases are often confounded in treatises on inheritance. 

Lastly, the hybrids or mongrels from between all the domestic breeds of pigeons are perfectly fertile. I can state this from my own observations, purposely made on the most distinct breeds. Now, it is difficult, perhaps impossible, to bring forward one case of the hybrid offspring of two animals clearly distinct being themselves perfectly fertile. Some authors believe that long-continued domestication eliminates this strong tendency to sterility: from the history of the dog I think there is some probability in this hypothesis, if applied to species closely related together, though it is unsupported by a single experiment. But to extend the hypothesis so far as to suppose that species, aboriginally as distinct as carriers, tumblers, pouters, and fantails now are, should yield offspring perfectly fertile, inter se, seems to me rash in the extreme. 

From these several reasons, namely, the improbability of man having formerly got seven or eight supposed species of pigeons to breed freely under domestication; these supposed species being quite unknown in a wild state, and their becoming nowhere feral; these species having very abnormal characters in certain respects, as compared with all other Columbidae, though so like in most other respects to the rock-pigeon; the blue colour and various marks occasionally appearing in all the breeds, both when kept pure and when crossed; the mongrel offspring being perfectly fertile; from these several reasons, taken together, I can feel no doubt that all our domestic breeds have descended from the Columba livia with its geographical sub-species. 

In favour of this view, I may add, firstly, that C. livia, or the rock-pigeon, has been found capable of domestication in Europe and in India; and that it agrees in habits and in a great number of points of structure with all the domestic breeds. Secondly, although an English carrier or short-faced tumbler differs immensely in certain characters from the rock-pigeon, yet by comparing the several sub-breeds of these breeds, more especially those brought from distant countries, we can make an almost perfect series between the extremes of structure. Thirdly, those characters which are mainly distinctive of each breed, for instance the wattle and length of beak of the carrier, the shortness of that of the tumbler, and the number of tail-feathers in the fantail, are in each breed eminently variable; and the explanation of this fact will be obvious when we come to treat of selection. Fourthly, pigeons have been watched, and tended with the utmost care, and loved by many people. They have been domesticated for thousands of years in several quarters of the world; the earliest known record of pigeons is in the fifth Aegyptian dynasty, about 3000 B.C., as was pointed out to me by Professor Lepsius; but Mr Birch informs me that pigeons are given in a bill of fare in the previous dynasty. In the time of the Romans, as we hear from Pliny, immense prices were given for pigeons; 'nay, they are come to this pass, that they can reckon up their pedigree and race.' Pigeons were much valued by Akber Khan in India, about the year 1600; never less than 20,000 pigeons were taken with the court. 'The monarchs of Iran and Turan sent him some very rare birds;' and, continues the courtly historian, 'His Majesty by crossing the breeds, which method was never practised before, has improved them astonishingly.' About this same period the Dutch were as eager about pigeons as were the old Romans. The paramount importance of these considerations in explaining the immense amount of variation which pigeons have undergone, will be obvious when we treat of Selection. We shall then, also, see how it is that the breeds so often have a somewhat monstrous character. It is also a most favourable circumstance for the production of distinct breeds, that male and female pigeons can be easily mated for life; and thus different breeds can be kept together in the same aviary. 

I have discussed the probable origin of domestic pigeons at some, yet quite insufficient, length; because when I first kept pigeons and watched the several kinds, knowing well how true they bred, I felt fully as much difficulty in believing that they could ever have descended from a common parent, as any naturalist could in coming to a similar conclusion in regard to the many species of finches, or other large groups of birds, in nature. One circumstance has struck me much; namely, that all the breeders of the various domestic animals and the cultivators of plants, with whom I have ever conversed, or whose treatises I have read, are firmly convinced that the several breeds to which each has attended, are descended from so many aboriginally distinct species. Ask, as I have asked, a celebrated raiser of Hereford cattle, whether his cattle might not have descended from long horns, and he will laugh you to scorn. I have never met a pigeon, or poultry, or duck, or rabbit fancier, who was not fully convinced that each main breed was descended from a distinct species. Van Mons, in his treatise on pears and apples, shows how utterly he disbelieves that the several sorts, for instance a Ribston-pippin or Codlin-apple, could ever have proceeded from the seeds of the same tree. Innumerable other examples could be given. The explanation, I think, is simple: from long-continued study they are strongly impressed with the differences between the several races; and though they well know that each race varies slightly, for they win their prizes by selecting such slight differences, yet they ignore all general arguments, and refuse to sum up in their minds slight differences accumulated during many successive generations. May not those naturalists who, knowing far less of the laws of inheritance than does the breeder, and knowing no more than he does of the intermediate links in the long lines of descent, yet admit that many of our domestic races have descended from the same parents may they not learn a lesson of caution, when they deride the idea of species in a state of nature being lineal descendants of other species? 


Selection
Let us now briefly consider the steps by which domestic races have been produced, either from one or from several allied species. Some little effect may, perhaps, be attributed to the direct action of the external conditions of life, and some little to habit; but he would be a bold man who would account by such agencies for the differences of a dray and race horse, a greyhound and bloodhound, a carrier and tumbler pigeon. One of the most remarkable features in our domesticated races is that we see in them adaptation, not indeed to the animal's or plant's own good, but to man's use or fancy. Some variations useful to him have probably arisen suddenly, or by one step; many botanists, for instance, believe that the fuller's teazle, with its hooks, which cannot be rivalled by any mechanical contrivance, is only a variety of the wild Dipsacus; and this amount of change may have suddenly arisen in a seedling. So it has probably been with the turnspit dog; and this is known to have been the case with the ancon sheep. But when we compare the dray-horse and race-horse, the dromedary and camel, the various breeds of sheep fitted either for cultivated land or mountain pasture, with the wool of one breed good for one purpose, and that of another breed for another purpose; when we compare the many breeds of dogs, each good for man in very different ways; when we compare the gamecock, so pertinacious in battle, with other breeds so little quarrelsome, with 'everlasting layers' which never desire to sit, and with the bantam so small and elegant; when we compare the host of agricultural, culinary, orchard, and flower-garden races of plants, most useful to man at different seasons and for different purposes, or so beautiful in his eyes, we must, I think, look further than to mere variability. We cannot suppose that all the breeds were suddenly produced as perfect and as useful as we now see them; indeed, in several cases, we know that this has not been their history. The key is man's power of accumulative selection: nature gives successive variations; man adds them up in certain directions useful to him. In this sense he may be said to make for himself useful breeds. 

The great power of this principle of selection is not hypothetical. It is certain that several of our eminent breeders have, even within a single lifetime, modified to a large extent some breeds of cattle and sheep. In order fully to realise what they have done, it is almost necessary to read several of the many treatises devoted to this subject, and to inspect the animals. Breeders habitually speak of an animal's organisation as something quite plastic, which they can model almost as they please. If I had space I could quote numerous passages to this effect from highly competent authorities. Youatt, who was probably better acquainted with the works of agriculturalists than almost any other individual, and who was himself a very good judge of an animal, speaks of the principle of selection as 'that which enables the agriculturist, not only to modify the character of his flock, but to change it altogether. It is the magician's wand, by means of which he may summon into life whatever form and mould he pleases.' Lord Somerville, speaking of what breeders have done for sheep, says: 'It would seem as if they had chalked out upon a wall a form perfect in itself, and then had given it existence.' That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that 'he would produce any given feather in three years, but it would take him six years to obtain head and beak.' In Saxony the importance of the principle of selection in regard to merino sheep is so fully recognised, that men follow it as a trade: the sheep are placed on a table and are studied, like a picture by a connoisseur; this is done three times at intervals of months, and the sheep are each time marked and classed, so that the very best may ultimately be selected for breeding. 

What English breeders have actually effected is proved by the enormous prices given for animals with a good pedigree; and these have now been exported to almost every quarter of the world. The improvement is by no means generally due to crossing different breeds; all the best breeders are strongly opposed to this practice, except sometimes amongst closely allied sub-breeds. And when a cross has been made, the closest selection is far more indispensable even than in ordinary cases. If selection consisted merely in separating some very distinct variety, and breeding from it, the principle would be so obvious as hardly to be worth notice; but its importance consists in the great effect produced by the accumulation in one direction, during successive generations, of differences absolutely inappreciable by an uneducated eye differences which I for one have vainly attempted to appreciate. Not one man in a thousand has accuracy of eye and judgement sufficient to become an eminent breeder. If gifted with these qualities, and he studies his subject for years, and devotes his lifetime to it with indomitable perseverance, he will succeed, and may make great improvements; if he wants any of these qualities, he will assuredly fail. Few would readily believe in the natural capacity and years of practice requisite to become even a skilful pigeon-fancier. 

The same principles are followed by horticulturists; but the variations are here often more abrupt. No one supposes that our choicest productions have been produced by a single variation from the aboriginal stock. We have proofs that this is not so in some cases, in which exact records have been kept; thus, to give a very trifling instance, the steadily-increasing size of the common gooseberry may be quoted. We see an astonishing improvement in many florists' flowers, when the flowers of the present day are compared with drawings made only twenty or thirty years ago. When a race of plants is once pretty well established, the seed-raisers do not pick out the best plants, but merely go over their seed-beds, and pull up the 'rogues,' as they call the plants that deviate from the proper standard. With animals this kind of selection is, in fact, also followed; for hardly any one is so careless as to allow his worst animals to breed. 

In regard to plants, there is another means of observing the accumulated effects of selection namely, by comparing the diversity of flowers in the different varieties of the same species in the flower-garden; the diversity of leaves, pods, or tubers, or whatever part is valued, in the kitchen-garden, in comparison with the flowers of the same varieties; and the diversity of fruit of the same species in the orchard, in comparison with the leaves and flowers of the same set of varieties. See how different the leaves of the cabbage are, and how extremely alike the flowers; how unlike the flowers of the heartsease are, and how alike the leaves; how much the fruit of the different kinds of gooseberries differ in size, colour, shape, and hairiness, and yet the flowers present very slight differences. It is not that the varieties which differ largely in some one point do not differ at all in other points; this is hardly ever, perhaps never, the case. The laws of correlation of growth, the importance of which should never be overlooked, will ensure some differences; but, as a general rule, I cannot doubt that the continued selection of slight variations, either in the leaves, the flowers, or the fruit, will produce races differing from each other chiefly in these characters. 

It may be objected that the principle of selection has been reduced to methodical practice for scarcely more than three-quarters of a century; it has certainly been more attended to of late years, and many treatises have been published on the subject; and the result, I may add, has been, in a corresponding degree, rapid and important. But it is very far from true that the principle is a modern discovery. I could give several references to the full acknowledgement of the importance of the principle in works of high antiquity. In rude and barbarous periods of English history choice animals were often imported, and laws were passed to prevent their exportation: the destruction of horses under a certain size was ordered, and this may be compared to the 'roguing' of plants by nurserymen. The principle of selection I find distinctly given in an ancient Chinese encyclopaedia. Explicit rules are laid down by some of the Roman classical writers. From passages in Genesis, it is clear that the colour of domestic animals was at that early period attended to. Savages now sometimes cross their dogs with wild canine animals, to improve the breed, and they formerly did so, as is attested by passages in Pliny. The savages in South Africa match their draught cattle by colour, as do some of the Esquimaux their teams of dogs. Livingstone shows how much good domestic breeds are valued by the negroes of the interior of Africa who have not associated with Europeans. Some of these facts do not show actual selection, but they show that the breeding of domestic animals was carefully attended to in ancient times, and is now attended to by the lowest savages. It would, indeed, have been a strange fact, had attention not been paid to breeding, for the inheritance of good and bad qualities is so obvious. 

At the present time, eminent breeders try by methodical selection, with a distinct object in view, to make a new strain or sub-breed, superior to anything existing in the country. But, for our purpose, a kind of Selection, which may be called Unconscious, and which results from every one trying to possess and breed from the best individual animals, is more important. Thus, a man who intends keeping pointers naturally tries to get as good dogs as he can, and afterwards breeds from his own best dogs, but he has no wish or expectation of permanently altering the breed. Nevertheless I cannot doubt that this process, continued during centuries, would improve and modify any breed, in the same way as Bakewell, Collins, &c., by this very same process, only carried on more methodically, did greatly modify, even during their own lifetimes, the forms and qualities of their cattle. Slow and insensible changes of this kind could never be recognised unless actual measurements or careful drawings of the breeds in question had been made long ago, which might serve for comparison. In some cases, however, unchanged or but little changed individuals of the same breed may be found in less civilised districts, where the breed has been less improved. There is reason to believe that King Charles's spaniel has been unconsciously modified to a large extent since the time of that monarch. Some highly competent authorities are convinced that the setter is directly derived from the spaniel, and has probably been slowly altered from it. It is known that the English pointer has been greatly changed within the last century, and in this case the change has, it is believed, been chiefly effected by crosses with the fox-hound; but what concerns us is, that the change has been effected unconsciously and gradually, and yet so effectually, that, though the old Spanish pointer certainly came from Spain, Mr Barrow has not seen, as I am informed by him, any native dog in Spain like our pointer. 

By a similar process of selection, and by careful training, the whole body of English racehorses have come to surpass in fleetness and size the parent Arab stock, so that the latter, by the regulations for the Goodwood Races, are favoured in the weights they carry. Lord Spencer and others have shown how the cattle of England have increased in weight and in early maturity, compared with the stock formerly kept in this country. By comparing the accounts given in old pigeon treatises of carriers and tumblers with these breeds as now existing in Britain, India, and Persia, we can, I think, clearly trace the stages through which they have insensibly passed, and come to differ so greatly from the rock-pigeon. 

Youatt gives an excellent illustration of the effects of a course of selection, which may be considered as unconsciously followed, in so far that the breeders could never have expected or even have wished to have produced the result which ensued namely, the production of two distinct strains. The two flocks of Leicester sheep kept by Mr Buckley and Mr Burgess, as Mr Youatt remarks, 'have been purely bred from the original stock of Mr Bakewell for upwards of fifty years. There is not a suspicion existing in the mind of any one at all acquainted with the subject that the owner of either of them has deviated in any one instance from the pure blood of Mr Bakewell's flock, and yet the difference between the sheep possessed by these two gentlemen is so great that they have the appearance of being quite different varieties.' 

If there exist savages so barbarous as never to think of the inherited character of the offspring of their domestic animals, yet any one animal particularly useful to them, for any special purpose, would be carefully preserved during famines and other accidents, to which savages are so liable, and such choice animals would thus generally leave more offspring than the inferior ones; so that in this case there would be a kind of unconscious selection going on. We see the value set on animals even by the barbarians of Tierra del Fuego, by their killing and devouring their old women, in times of dearth, as of less value than their dogs. 

In plants the same gradual process of improvement, through the occasional preservation of the best individuals, whether or not sufficiently distinct to be ranked at their first appearance as distinct varieties, and whether or not two or more species or races have become blended together by crossing, may plainly be recognised in the increased size and beauty which we now see in the varieties of the heartsease, rose, pelargonium, dahlia, and other plants, when compared with the older varieties or with their parent-stocks. No one would ever expect to get a first-rate heartsease or dahlia from the seed of a wild plant. No one would expect to raise a first-rate melting pear from the seed of a wild pear, though he might succeed from a poor seedling growing wild, if it had come from a garden-stock. The pear, though cultivated in classical times, appears, from Pliny's description, to have been a fruit of very inferior quality. I have seen great surprise expressed in horticultural works at the wonderful skill of gardeners, in having produced such splendid results from such poor materials; but the art, I cannot doubt, has been simple, and, as far as the final result is concerned, has been followed almost unconsciously. It has consisted in always cultivating the best known variety, sowing its seeds, and, when a slightly better variety has chanced to appear, selecting it, and so onwards. But the gardeners of the classical period, who cultivated the best pear they could procure, never thought what splendid fruit we should eat; though we owe our excellent fruit, in some small degree, to their having naturally chosen and preserved the best varieties they could anywhere find. 

A large amount of change in our cultivated plants, thus slowly and unconsciously accumulated, explains, as I believe, the well-known fact, that in a vast number of cases we cannot recognise, and therefore do not know, the wild parent-stocks of the plants which have been longest cultivated in our flower and kitchen gardens. If it has taken centuries or thousands of years to improve or modify most of our plants up to their present standard of usefulness to man, we can understand how it is that neither Australia, the Cape of Good Hope, nor any other region inhabited by quite uncivilised man, has afforded us a single plant worth culture. It is not that these countries, so rich in species, do not by a strange chance possess the aboriginal stocks of any useful plants, but that the native plants have not been improved by continued selection up to a standard of perfection comparable with that given to the plants in countries anciently civilised. 

In regard to the domestic animals kept by uncivilised man, it should not be overlooked that they almost always have to struggle for their own food, at least during certain seasons. And in two countries very differently circumstanced, individuals of the same species, having slightly different constitutions or structure, would often succeed better in the one country than in the other, and thus by a process of 'natural selection,' as will hereafter be more fully explained, two sub-breeds might be formed. This, perhaps, partly explains what has been remarked by some authors, namely, that the varieties kept by savages have more of the character of species than the varieties kept in civilised countries. 

On the view here given of the all-important part which selection by man has played, it becomes at once obvious, how it is that our domestic races show adaptation in their structure or in their habits to man's wants or fancies. We can, I think, further understand the frequently abnormal character of our domestic races, and likewise their differences being so great in external characters and relatively so slight in internal parts or organs. Man can hardly select, or only with much difficulty, any deviation of structure excepting such as is externally visible; and indeed he rarely cares for what is internal. He can never act by selection, excepting on variations which are first given to him in some slight degree by nature. No man would ever try to make a fantail, till he saw a pigeon with a tail developed in some slight degree in an unusual manner, or a pouter till he saw a pigeon with a crop of somewhat unusual size; and the more abnormal or unusual any character was when it first appeared, the more likely it would be to catch his attention. But to use such an expression as trying to make a fantail, is, I have no doubt, in most cases, utterly incorrect. The man who first selected a pigeon with a slightly larger tail, never dreamed what the descendants of that pigeon would become through long-continued, partly unconscious and partly methodical selection. Perhaps the parent bird of all fantails had only fourteen tail-feathers somewhat expanded, like the present Java fantail, or like individuals of other and distinct breeds, in which as many as seventeen tail-feathers have been counted. Perhaps the first pouter-pigeon did not inflate its crop much more than the turbit now does the upper part of its oesophagus, a habit which is disregarded by all fanciers, as it is not one of the points of the breed. 

Nor let it be thought that some great deviation of structure would be necessary to catch the fancier's eye: he perceives extremely small differences, and it is in human nature to value any novelty, however slight, in one's own possession. Nor must the value which would formerly be set on any slight differences in the individuals of the same species, be judged of by the value which would now be set on them, after several breeds have once fairly been established. Many slight differences might, and indeed do now, arise amongst pigeons, which are rejected as faults or deviations from the standard of perfection of each breed. The common goose has not given rise to any marked varieties; hence the Thoulouse and the common breed, which differ only in colour, that most fleeting of characters, have lately been exhibited as distinct at our poultry-shows. 

I think these views further explain what has sometimes been noticed namely that we know nothing about the origin or history of any of our domestic breeds. But, in fact, a breed, like a dialect of a language, can hardly be said to have had a definite origin. A man preserves and breeds from an individual with some slight deviation of structure, or takes more care than usual in matching his best animals and thus improves them, and the improved individuals slowly spread in the immediate neighbourhood. But as yet they will hardly have a distinct name, and from being only slightly valued, their history will be disregarded. When further improved by the same slow and gradual process, they will spread more widely, and will get recognised as something distinct and valuable, and will then probably first receive a provincial name. In semi-civilised countries, with little free communication, the spreading and knowledge of any new sub-breed will be a slow process. As soon as the points of value of the new sub-breed are once fully acknowledged, the principle, as I have called it, of unconscious selection will always tend, perhaps more at one period than at another, as the breed rises or falls in fashion, perhaps more in one district than in another, according to the state of civilisation of the inhabitants slowly to add to the characteristic features of the breed, whatever they may be. But the chance will be infinitely small of any record having been preserved of such slow, varying, and insensible changes. 

I must now say a few words on the circumstances, favourable, or the reverse, to man's power of selection. A high degree of variability is obviously favourable, as freely giving the materials for selection to work on; not that mere individual differences are not amply sufficient, with extreme care, to allow of the accumulation of a large amount of modification in almost any desired direction. But as variations manifestly useful or pleasing to man appear only occasionally, the chance of their appearance will be much increased by a large number of individuals being kept; and hence this comes to be of the highest importance to success. On this principle Marshall has remarked, with respect to the sheep of parts of Yorkshire, that 'as they generally belong to poor people, and are mostly in small lots, they never can be improved.' On the other hand, nurserymen, from raising large stocks of the same plants, are generally far more successful than amateurs in getting new and valuable varieties. The keeping of a large number of individuals of a species in any country requires that the species should be placed under favourable conditions of life, so as to breed freely in that country. When the individuals of any species are scanty, all the individuals, whatever their quality may be, will generally be allowed to breed, and this will effectually prevent selection. But probably the most important point of all, is, that the animal or plant should be so highly useful to man, or so much valued by him, that the closest attention should be paid to even the slightest deviation in the qualities or structure of each individual. Unless such attention be paid nothing can be effected. I have seen it gravely remarked, that it was most fortunate that the strawberry began to vary just when gardeners began to attend closely to this plant. No doubt the strawberry had always varied since it was cultivated, but the slight varieties had been neglected. As soon, however, as gardeners picked out individual plants with slightly larger, earlier, or better fruit, and raised seedlings from them, and again picked out the best seedlings and bred from them, then, there appeared (aided by some crossing with distinct species) those many admirable varieties of the strawberry which have been raised during the last thirty or forty years. 

In the case of animals with separate sexes, facility in preventing crosses is an important element of success in the formation of new races, at least, in a country which is already stocked with other races. In this respect enclosure of the land plays a part. Wandering savages or the inhabitants of open plains rarely possess more than one breed of the same species. Pigeons can be mated for life, and this is a great convenience to the fancier, for thus many races may be kept true, though mingled in the same aviary; and this circumstance must have largely favoured the improvement and formation of new breeds. Pigeons, I may add, can be propagated in great numbers and at a very quick rate, and inferior birds may be freely rejected, as when killed they serve for food. On the other hand, cats, from their nocturnal rambling habits, cannot be matched, and, although so much valued by women and children, we hardly ever see a distinct breed kept up; such breeds as we do sometimes see are almost always imported from some other country, often from islands. Although I do not doubt that some domestic animals vary less than others, yet the rarity or absence of distinct breeds of the cat, the donkey, peacock, goose, &c., may be attributed in main part to selection not having been brought into play: in cats, from the difficulty in pairing them; in donkeys, from only a few being kept by poor people, and little attention paid to their breeding; in peacocks, from not being very easily reared and a large stock not kept; in geese, from being valuable only for two purposes, food and feathers, and more especially from no pleasure having been felt in the display of distinct breeds. 

To sum up on the origin of our Domestic Races of animals and plants. I believe that the conditions of life, from their action on the reproductive system, are so far of the highest importance as causing variability. I do not believe that variability is an inherent and necessary contingency, under all circumstances, with all organic beings, as some authors have thought. The effects of variability are modified by various degrees of inheritance and of reversion. Variability is governed by many unknown laws, more especially by that of correlation of growth. Something may be attributed to the direct action of the conditions of life. Something must be attributed to use and disuse. The final result is thus rendered infinitely complex. In some cases, I do not doubt that the intercrossing of species, aboriginally distinct, has played an important part in the origin of our domestic productions. When in any country several domestic breeds have once been established, their occasional intercrossing, with the aid of selection, has, no doubt, largely aided in the formation of new sub-breeds; but the importance of the crossing of varieties has, I believe, been greatly exaggerated, both in regard to animals and to those plants which are propagated by seed. In plants which are temporarily propagated by cuttings, buds, &c., the importance of the crossing both of distinct species and of varieties is immense; for the cultivator here quite disregards the extreme variability both of hybrids and mongrels, and the frequent sterility of hybrids; but the cases of plants not propagated by seed are of little importance to us, for their endurance is only temporary. Over all these causes of Change I am convinced that the accumulative action of Selection, whether applied methodically and more quickly, or unconsciously and more slowly, but more efficiently, is by far the predominant power. 

BEFORE applying the principles arrived at in the last chapter to organic beings in a state of nature, we must briefly discuss whether these latter are subject to any variation. To treat this subject at all properly, a long catalogue of dry facts should be given; but these I shall reserve for my future work. Nor shall I here discuss the various definitions which have been given of the term species. No one definition has as yet satisfied all naturalists; yet every naturalist knows vaguely what he means when he speaks of a species. Generally the term includes the unknown element of a distinct act of creation. The term 'variety' is almost equally difficult to define; but here community of descent is almost universally implied, though it can rarely be proved. We have also what are called monstrosities; but they graduate into varieties. By a monstrosity I presume is meant some considerable deviation of structure in one part, either injurious to or not useful to the species, and not generally propagated. Some authors use the term 'variation' in a technical sense, as implying a modification directly due to the physical conditions of life; and 'variations' in this sense are supposed not to be inherited: but who can say that the dwarfed condition of shells in the brackish waters of the Baltic, or dwarfed plants on Alpine summits, or the thicker fur of an animal from far northwards, would not in some cases be inherited for at least some few generations? and in this case I presume that the form would be called a variety.

Again, we have many slight differences which may be called individual differences, such as are known frequently to appear in the offspring from the same parents, or which may be presumed to have thus arisen, from being frequently observed in the individuals of the same species inhabiting the same confined locality. No one supposes that all the individuals of the same species are cast in the very same mould. These individual differences are highly important for us, as they afford materials for natural selection to accumulate, in the same manner as man can accumulate in any given direction individual differences in his domesticated productions. These individual differences generally affect what naturalists consider unimportant parts; but I could show by a long catalogue of facts, that parts which must be called important, whether viewed under a physiological or classificatory point of view, sometimes vary in the individuals of the same species. I am convinced that the most experienced naturalist would be surprised at the number of the cases of variability, even in important parts of structure, which he could collect on good authority, as I have collected, during a course of years. It should be remembered that systematists are far from pleased at finding variability in important characters, and that there are not many men who will laboriously examine internal and important organs, and compare them in many specimens of the same species. I should never have expected that the branching of the main nerves close to the great central ganglion of an insect would have been variable in the same species; I should have expected that changes of this nature could have been effected only by slow degrees: yet quite recently Mr Lubbock has shown a degree of variability in these main nerves in Coccus, which may almost be compared to the irregular branching of the stem of a tree. This philosophical naturalist, I may add, has also quite recently shown that the muscles in the larvae of certain insects are very far from uniform. Authors sometimes argue in a circle when they state that important organs never vary; for these same authors practically rank that character as important (as some few naturalists have honestly confessed) which does not vary; and, under this point of view, no instance of any important part varying will ever be found: but under any other point of view many instances assuredly can be given.

There is one point connected with individual differences, which seems to me extremely perplexing: I refer to those genera which have sometimes been called 'protean' or 'polymorphic,' in which the species present an inordinate amount of variation; and hardly two naturalists can agree which forms to rank as species and which as varieties. We may instance Rubus, Rosa, and Hieracium amongst plants, several genera of insects, and several genera of Brachiopod shells. In most polymorphic genera some of the species have fixed and definite characters. Genera which are polymorphic in one country seem to be, with some few exceptions, polymorphic in other countries, and likewise, judging from Brachiopod shells, at former periods of time. These facts seem to be very perplexing, for they seem to show that this kind of variability is independent of the conditions of life. I am inclined to suspect that we see in these polymorphic genera variations in points of structure which are of no service or disservice to the species, and which consequently have not been seized on and rendered definite by natural selection, as hereafter will be explained.

Those forms which possess in some considerable degree the character of species, but which are so closely similar to some other forms, or are so closely linked to them by intermediate gradations, that naturalists do not like to rank them as distinct species, are in several respects the most important for us. We have every reason to believe that many of these doubtful and closely-allied forms have permanently retained their characters in their own country for a long time; for as long, as far as we know, as have good and true species. practically, when a naturalist can unite two forms together by others having intermediate characters, he treats the one as a variety of the other, ranking the most common, but sometimes the one first described, as the species, and the other as the variety. But cases of great difficulty, which I will not here enumerate, sometimes occur in deciding whether or not to rank one form as a variety of another, even when they are closely connected by intermediate links; nor will the commonly-assumed hybrid nature of the intermediate links always remove the difficulty. In very many cases, however, one form is ranked as a variety of another, not because the intermediate links have actually been found, but because analogy leads the observer to suppose either that they do now somewhere exist, or may formerly have existed; and here a wide door for the entry of doubt and conjecture is opened.

Hence, in determining whether a form should be ranked as a species or a variety, the opinion of naturalists having sound judgement and wide experience seems the only guide to follow. We must, however, in many cases, decide by a majority of naturalists, for few well-marked and well-known varieties can be named which have not been ranked as species by at least some competent judges.

That varieties of this doubtful nature are far from uncommon cannot be disputed. Compare the several floras of Great Britain, of France or of the United States, drawn up by different botanists, and see what a surprising number of forms have been ranked by one botanist as good species, and by another as mere varieties. Mr H. C. Watson, to whom I lie under deep obligation for assistance of all kinds, has marked for me 182 British plants, which are generally considered as varieties, but which have all been ranked by botanists as species; and in making this list he has omitted many trifling varieties, but which nevertheless have been ranked by some botanists as species, and he has entirely omitted several highly polymorphic genera. Under genera, including the most polymorphic forms, Mr Babington gives 251 species, whereas Mr Bentham gives only 112, a difference of 139 doubtful forms! Amongst animals which unite for each birth, and which are highly locomotive, doubtful forms, ranked by one zoologist as a species and by another as a variety, can rarely be found within the same country, but are common in separated areas. How many of those birds and insects in North America and Europe, which differ very slightly from each other, have been ranked by one eminent naturalist as undoubted species, and by another as varieties, or, as they are often called, as geographical races! Many years ago, when comparing, and seeing others compare, the birds from the separate islands of the Galapagos Archipelago, both one with another, and with those from the American mainland, I was much struck how entirely vague and arbitrary is the distinction between species and varieties. On the islets of the little Madeira group there are many insects which are characterized as varieties in Mr Wollaston's admirable work, but which it cannot be doubted would be ranked as distinct species by many entomologists. Even Ireland has a few animals, now generally regarded as varieties, but which have been ranked as species by some zoologists. Several most experienced ornithologists consider our British red grouse as only a strongly-marked race of a Norwegian species, whereas the greater number rank it as an undoubted species peculiar to Great Britain. A wide distance between the homes of two doubtful forms leads many naturalists to rank both as distinct species; but what distance, it has been well asked, will suffice? if that between America and Europe is ample, will that between the Continent and the Azores, or Madeira, or the Canaries, or Ireland, be sufficient? It must be admitted that many forms, considered by highly-competent judges as varieties, have so perfectly the character of species that they are ranked by other highly-competent judges as good and true species. But to discuss whether they are rightly called species or varieties, before any definition of these terms has been generally accepted, is vainly to beat the air.

Many of the cases of strongly-marked varieties or doubtful species well deserve consideration; for several interesting lines of argument, from geographical distribution, analogical variation, hybridism, &c., have been brought to bear on the attempt to determine their rank. I will here give only a single instance, the well-known one of the primrose and cowslip, or Primula veris and elatior. These plants differ considerably in appearance; they have a different flavour and emit a different odour; they flower at slightly different periods; they grow in somewhat different stations; they ascend mountains to different heights; they have different geographical ranges; and lastly, according to very numerous experiments made during several years by that most careful observer Gärtner, they can be crossed only with much difficulty. We could hardly wish for better evidence of the two forms being specifically distinct. On the other hand, they are united by many intermediate links, and it is very doubtful whether these links are hybrids; and there is, as it seems to me, an overwhelming amount of experimental evidence, showing that they descend from common parents, and consequently must be ranked as varieties.

Close investigation, in most cases, will bring naturalists to an agreement how to rank doubtful forms. Yet it must be confessed, that it is in the best-known countries that we find the greatest number of forms of doubtful value. I have been struck with the fact, that if any animal or plant in a state of nature be highly useful to man, or from any cause closely attract his attention, varieties of it will almost universally be found recorded. These varieties, moreover, will be often ranked by some authors as species. Look at the common oak, how closely it has been studied; yet a German author makes more than a dozen species out of forms, which are very generally considered as varieties; and in this country the highest botanical authorities and practical men can be quoted to show that the sessile and pedunculated oaks are either good and distinct species or mere varieties.

When a young naturalist commences the study of a group of organisms quite unknown to him, he is at first much perplexed to determine what differences to consider as specific, and what as varieties; for he knows nothing of the amount and kind of variation to which the group is subject; and this shows, at least, how very generally there is some variation. But if he confine his attention to one class within one country, he will soon make up his mind how to rank most of the doubtful forms. His general tendency will be to make many species, for he will become impressed, just like the pigeon or poultry-fancier before alluded to, with the amount of difference in the forms which he is continually studying; and he has little general knowledge of analogical variation in other groups and in other countries, by which to correct his first impressions. As he extends the range of his observations, he will meet with more cases of difficulty; for he will encounter a greater number of closely-allied forms. But if his observations be widely extended, he will in the end generally be enabled to make up his own mind which to call varieties and which species; but he will succeed in this at the expense of admitting much variation, and the truth of this admission will often be disputed by other naturalists. When, moreover, he comes to study allied forms brought from countries not now continuous, in which case he can hardly hope to find the intermediate links between his doubtful forms, he will have to trust almost entirely to analogy, and his difficulties will rise to a climax.

Certainly no clear line of demarcation has as yet been drawn between species and sub-species that is, the forms which in the opinion of some naturalists come very near to, but do not quite arrive at the rank of species; or, again, between sub-species and well-marked varieties, or between lesser varieties and individual differences. These differences blend into each other in an insensible series; and a series impresses the mind with the idea of an actual passage.

Hence I look at individual differences, though of small interest to the systematist, as of high importance for us, as being the first step towards such slight varieties as are barely thought worth recording in works on natural history. And I look at varieties which are in any degree more distinct and permanent, as steps leading to more strongly marked and more permanent varieties; and at these latter, as leading to sub-species, and to species. The passage from one stage of difference to another and higher stage may be, in some cases, due merely to the long-continued action of different physical conditions in two different regions; but I have not much faith in this view; and I attribute the passage of a variety, from a state in which it differs very slightly from its parent to one in which it differs more, to the action of natural selection in accumulating (as will hereafter be more fully explained) differences of structure in certain definite directions. Hence I believe a well-marked variety may be justly called an incipient species; but whether this belief be justifiable must be judged of by the general weight of the several facts and views given throughout this work.

It need not be supposed that all varieties or incipient species necessarily attain the rank of species. They may whilst in this incipient state become extinct, or they may endure as varieties for very long periods, as has been shown to be the case by Mr Wollaston with the varieties of certain fossil land-shells in Madeira. If a variety were to flourish so as to exceed in numbers the parent species, it would then rank as the species, and the species as the variety; or it might come to supplant and exterminate the parent species; or both might co-exist, and both rank as independent species. But we shall hereafter have to return to this subject.

From these remarks it will be seen that I look at the term species, as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other, and that it does not essentially differ from the term variety, which is given to less distinct and more fluctuating forms. The term variety, again, in comparison with mere individual differences, is also applied arbitrarily, and for mere convenience sake.

Guided by theoretical considerations, I thought that some interesting results might be obtained in regard to the nature and relations of the species which vary most, by tabulating all the varieties in several well-worked floras. At first this seemed a simple task; but Mr H. C. Watson, to whom I am much indebted for valuable advice and assistance on this subject, soon convinced me that there were many difficulties, as did subsequently Dr Hooker, even in stronger terms. I shall reserve for my future work the discussion of these difficulties, and the tables themselves of the proportional numbers of the varying species. Dr Hooker permits me to add, that after having carefully read my manuscript, and examined the tables, he thinks that the following statements are fairly well established. The whole subject, however, treated as it necessarily here is with much brevity, is rather perplexing, and allusions cannot be avoided to the 'struggle for existence,' 'divergence of character,' and other questions, hereafter to be discussed.

Alph. De Candolle and others have shown that plants which have very wide ranges generally present varieties; and this might have been expected, as they become exposed to diverse physical conditions, and as they come into competition (which, as we shall hereafter see, is a far more important circumstance) with different sets of organic beings. But my tables further show that, in any limited country, the species which are most common, that is abound most in individuals, and the species which are most widely diffused within their own country (and this is a different consideration from wide range, and to a certain extent from commonness), often give rise to varieties sufficiently well-marked to have been recorded in botanical works. Hence it is the most flourishing, or, as they may be called, the dominant species, those which range widely over the world, are the most diffused in their own country, and are the most numerous in individuals, which oftenest produce well-marked varieties, or, as I consider them, incipient species. And this, perhaps, might have been anticipated; for, as varieties, in order to become in any degree permanent, necessarily have to struggle with the other inhabitants of the country, the species which are already dominant will be the most likely to yield offspring which, though in some slight degree modified, will still inherit those advantages that enabled their parents to become dominant over their compatriots.

If the plants inhabiting a country and described in any Flora be divided into two equal masses, all those in the larger genera being placed on one side, and all those in the smaller genera on the other side, a somewhat larger number of the very common and much diffused or dominant species will be found on the side of the larger genera. This, again, might have been anticipated; for the mere fact of many species of the same genus inhabiting any country, shows that there is something in the organic or inorganic conditions of that country favourable to the genus; and, consequently, we might have expected to have found in the larger genera, or those including many species, a large proportional number of dominant species. But so many causes tend to obscure this result, that I am surprised that my tables show even a small majority on the side of the larger genera. I will here allude to only two causes of obscurity. Fresh-water and salt-loving plants have generally very wide ranges and are much diffused, but this seems to be connected with the nature of the stations inhabited by them, and has little or no relation to the size of the genera to which the species belong. Again, plants low in the scale of organisation are generally much more widely diffused than plants higher in the scale; and here again there is no close relation to the size of the genera. The cause of lowly-organised plants ranging widely will be discussed in our chapter on geographical distribution.

From looking at species as only strongly-marked and well-defined varieties, I was led to anticipate that the species of the larger genera in each country would oftener present varieties, than the species of the smaller genera; for wherever many closely related species (i.e. species of the same genus) have been formed, many varieties or incipient species ought, as a general rule, to be now forming. Where many large trees grow, we expect to find saplings. Where many species of a genus have been formed through variation, circumstances have been favourable for variation; and hence we might expect that the circumstances would generally be still favourable to variation. On the other hand, if we look at each species as a special act of creation, there is no apparent reason why more varieties should occur in a group having many species, than in one having few.

To test the truth of this anticipation I have arranged the plants of twelve countries, and the coleopterous insects of two districts, into two nearly equal masses, the species of the larger genera on one side, and those of the smaller genera on the other side, and it has invariably proved to be the case that a larger proportion of the species on the side of the larger genera present varieties, than on the side of the smaller genera. Moreover, the species of the large genera which present any varieties, invariably present a larger average number of varieties than do the species of the small genera. Both these results follow when another division is made, and when all the smallest genera, with from only one to four species, are absolutely excluded from the tables. These facts are of plain signification on the view that species are only strongly marked and permanent varieties; for whenever many species of the same genus have been formed, or where, if we may use the expression, the manufactory of species has been active, we ought generally to find the manufactory still in action, more especially as we have every reason to believe the process of manufacturing new species to be a slow one. And this certainly is the case, if varieties be looked at as incipient species; for my tables clearly show as a general rule that, wherever many species of a genus have been formed, the species of that genus present a number of varieties, that is of incipient species, beyond the average. It is not that all large genera are now varying much, and are thus increasing in the number of their species, or that no small genera are now varying and increasing; for if this had been so, it would have been fatal to my theory; inasmuch as geology plainly tells us that small genera have in the lapse of time often increased greatly in size; and that large genera have often come to their maxima, declined, and disappeared. All that we want to show is, that where many species of a genus have been formed, on an average many are still forming; and this holds good.

There are other relations between the species of large genera and their recorded varieties which deserve notice. We have seen that there is no infallible criterion by which to distinguish species and well-marked varieties; and in those cases in which intermediate links have not been found between doubtful forms, naturalists are compelled to come to a determination by the amount of difference between them, judging by analogy whether or not the amount suffices to raise one or both to the rank of species. Hence the amount of difference is one very important criterion in settling whether two forms should be ranked as species or varieties. Now Fries has remarked in regard to plants, and Westwood in regard to insects, that in large genera the amount of difference between the species is often exceedingly small. I have endeavoured to test this numerically by averages, and, as far as my imperfect results go, they always confirm the view. I have also consulted some sagacious and most experienced observers, and, after deliberation, they concur in this view. In this respect, therefore, the species of the larger genera resemble varieties, more than do the species of the smaller genera. Or the case may be put in another way, and it may be said, that in the larger genera, in which a number of varieties or incipient species greater than the average are now manufacturing, many of the species already manufactured still to a certain extent resemble varieties, for they differ from each other by a less than usual amount of difference.

Moreover, the species of the large genera are related to each other, in the same manner as the varieties of any one species are related to each other. No naturalist pretends that all the species of a genus are equally distinct from each other; they may generally be divided into sub-genera, or sections, or lesser groups. As Fries has well remarked, little groups of species are generally clustered like satellites around certain other species. And what are varieties but groups of forms, unequally related to each other, and clustered round certain forms that is, round their parent-species? Undoubtedly there is one most important point of difference between varieties and species; namely, that the amount of difference between varieties, when compared with each other or with their parent-species, is much less than that between the species of the same genus. But when we come to discuss the principle, as I call it, of Divergence of Character, we shall see how this may be explained, and how the lesser differences between varieties will tend to increase into the greater differences between species.

There is one other point which seems to me worth notice. Varieties generally have much restricted ranges: this statement is indeed scarcely more than a truism, for if a variety were found to have a wider range than that of its supposed parent-species, their denominations ought to be reversed. But there is also reason to believe, that those species which are very closely allied to other species, and in so far resemble varieties, often have much restricted ranges. For instance, Mr H. C. Watson has marked for me in the well-sifted London Catalogue of plants (4th edition) 63 plants which are therein ranked as species, but which he considers as so closely allied to other species as to be of doubtful value: these 63 reputed species range on an average over 6.9 of the provinces into which Mr Watson has divided Great Britain. Now, in this same catalogue, 53 acknowledged varieties are recorded, and these range over 7.7 provinces; whereas, the species to which these varieties belong range over 14.3 provinces. So that the acknowledged varieties have very nearly the same restricted average range, as have those very closely allied forms, marked for me by Mr Watson as doubtful species, but which are almost universally ranked by British botanists as good and true species.

Finally, then, varieties have the same general characters as species, for they cannot be distinguished from species, except, firstly, by the discovery of intermediate linking forms, and the occurrence of such links cannot affect the actual characters of the forms which they connect; and except, secondly, by a certain amount of difference, for two forms, if differing very little, are generally ranked as varieties, notwithstanding that intermediate linking forms have not been discovered; but the amount of difference considered necessary to give to two forms the rank of species is quite indefinite. In genera having more than the average number of species in any country, the species of these genera have more than the average number of varieties. In large genera the species are apt to be closely, but unequally, allied together, forming little clusters round certain species. Species very closely allied to other species apparently have restricted ranges. In all these several respects the species of large genera present a strong analogy with varieties. And we can clearly understand these analogies, if species have once existed as varieties, and have thus originated: whereas, these analogies are utterly inexplicable if each species has been independently created.

We have, also, seen that it is the most flourishing and dominant species of the larger genera which on an average vary most; and varieties, as we shall hereafter see, tend to become converted into new and distinct species. The larger genera thus tend to become larger; and throughout nature the forms of life which are now dominant tend to become still more dominant by leaving many modified and dominant descendants. But by steps hereafter to be explained, the larger genera also tend to break up into smaller genera. And thus, the forms of life throughout the universe become divided into groups subordinate to groups. 
BEF0RE entering on the subject of this chapter, I must make a few preliminary remarks, to show how the struggle for existence bears on Natural Selection. It has been seen in the last chapter that amongst organic beings in a state of nature there is some individual variability; indeed I am not aware that this has ever been disputed. It is immaterial for us whether a multitude of doubtful forms be called species or sub-species or varieties; what rank, for instance, the two or three hundred doubtful forms of British plants are entitled to hold, if the existence of any well-marked varieties be admitted. But the mere existence of individual variability and of some few well-marked varieties, though necessary as the foundation for the work, helps us but little in understanding how species arise in nature. How have all those exquisite adaptations of one part of the organisation to another part, and to the conditions of life, and of one distinct organic being to another being, been perfected? We see these beautiful co-adaptations most plainly in the woodpecker and missletoe; and only a little less plainly in the humblest parasite which clings to the hairs of a quadruped or feathers of a bird; in the structure of the beetle which dives through the water; in the plumed seed which is wafted by the gentlest breeze; in short, we see beautiful adaptations everywhere and in every part of the organic world.

Again, it may be asked, how is it that varieties, which I have called incipient species, become ultimately converted into good and distinct species, which in most cases obviously differ from each other far more than do the varieties of the same species? How do those groups of species, which constitute what are called distinct genera, and which differ from each other more than do the species of the same genus, arise? All these results, as we shall more fully see in the next chapter, follow inevitably from the struggle for life. Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any degree profitable to an individual of any species, in its infinitely complex relations to other organic beings and to external nature, will tend to the preservation of that individual, and will generally be inherited by its offspring. The offspring, also, will thus have a better chance of surviving, for, of the many individuals of any species which are periodically born, but a small number can survive. I have called this principle, by which each slight variation, if useful, is preserved, by the term of Natural Selection, in order to mark its relation to man's power of selection. We have seen that man by selection can certainly produce great results, and can adapt organic beings to his own uses, through the accumulation of slight but useful variations, given to him by the hand of Nature. But Natural Selection, as we shall hereafter see, is a power incessantly ready for action, and is as immeasurably superior to man's feeble efforts, as the works of Nature are to those of Art.

We will now discuss in a little more detail the struggle for existence. In my future work this subject shall be treated, as it well deserves, at much greater length. The elder De Candolle and Lyell have largely and philosophically shown that all organic beings are exposed to severe competition. In regard to plants, no one has treated this subject with more spirit and ability than W. Herbert, Dean of Manchester, evidently the result of his great horticultural knowledge. Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult at least I have found it so than constantly to bear this conclusion in mind. Yet unless it be thoroughly engrained in the mind, I am convinced that the whole economy of nature, with every fact on distribution, rarity, abundance, extinction, and variation, will be dimly seen or quite misunderstood. We behold the face of nature bright with gladness, we often see superabundance of food; we do not see, or we forget, that the birds which are idly singing round us mostly live on insects or seeds, and are thus constantly destroying life; or we forget how largely these songsters, or their eggs, or their nestlings are destroyed by birds and beasts of prey; we do not always bear in mind, that though food may be now superabundant, it is not so at all seasons of each recurring year.

I should premise that I use the term Struggle for Existence in a large and metaphorical sense, including dependence of one being on another, and including (which is more important) not only the life of the individual, but success in leaving progeny. Two canine animals in a time of dearth, may be truly said to struggle with each other which shall get food and live. But a plant on the edge of a desert is said to struggle for life against the drought, though more properly it should be said to be dependent on the moisture. A plant which annually produces a thousand seeds, of which on an average only one comes to maturity, may be more truly said to struggle with the plants of the same and other kinds which already clothe the ground. The missletoe is dependent on the apple and a few other trees, but can only in a far-fetched sense be said to struggle with these trees, for if too many of these parasites grow on the same tree, it will languish and die. But several seedling missletoes, growing close together on the same branch, may more truly be said to struggle with each other. As the missletoe is disseminated by birds, its existence depends on birds; and it may metaphorically be said to struggle with other fruit-bearing plants, in order to tempt birds to devour and thus disseminate its seeds rather than those of other plants. In these several senses, which pass into each other, I use for convenience sake the general term of struggle for existence.

A struggle for existence inevitably follows from the high rate at which all organic beings tend to increase. Every being, which during its natural lifetime produces several eggs or seeds, must suffer destruction during some period of its life, and during some season or occasional year, otherwise, on the principle of geometrical increase, its numbers would quickly become so inordinately great that no country could support the product. Hence, as more individuals are produced than can possibly survive, there must in every case be a struggle for existence, either one individual with another of the same species, or with the individuals of distinct species, or with the physical conditions of life. It is the doctrine of Malthus applied with manifold force to the whole animal and vegetable kingdoms; for in this case there can be no artificial increase of food, and no prudential restraint from marriage. Although some species may be now increasing, more or less rapidly, in numbers, all cannot do so, for the world would not hold them.

There is no exception to the rule that every organic being naturally increases at so high a rate, that if not destroyed, the earth would soon be covered by the progeny of a single pair. Even slow-breeding man has doubled in twenty-five years, and at this rate, in a few thousand years, there would literally not be standing room for his progeny. Linnaeus has calculated that if an annual plant produced only two seeds and there is no plant so unproductive as this and their seedlings next year produced two, and so on, then in twenty years there would be a million plants. The elephant is reckoned to be the slowest breeder of all known animals, and I have taken some pains to estimate its probable minimum rate of natural increase: it will be under the mark to assume that it breeds when thirty years old, and goes on breeding till ninety years old, bringing forth three pairs of young in this interval; if this be so, at the end of the fifth century there would be alive fifteen million elephants, descended from the first pair.

But we have better evidence on this subject than mere theoretical calculations, namely, the numerous recorded cases of the astonishingly rapid increase of various animals in a state of nature, when circumstances have been favourable to them during two or three following seasons. Still more striking is the evidence from our domestic animals of many kinds which have run wild in several parts of the world: if the statements of the rate of increase of slow-breeding cattle and horses in South America, and latterly in Australia, had not been well authenticated, they would have been quite incredible. So it is with plants: cases could be given of introduced plants which have become common throughout whole islands in a period of less than ten years, Several of the plants now most numerous over the wide plains of La Plata, clothing square leagues of surface almost to the exclusion of all other plants, have been introduced from Europe; and there are plants which now range in India, as I hear from Dr Falconer, from Cape Comorin to the Himalaya, which have been imported from America since its discovery. In such cases, and endless instances could be given, no one supposes that the fertility of these animals or plants has been suddenly and temporarily increased in any sensible degree. The obvious explanation is that the conditions of life have been very favourable, and that there has consequently been less destruction of the old and young, and that nearly all the young have been enabled to breed. In such cases the geometrical ratio of increase, the result of which never fails to be surprising, simply explains the extraordinarily rapid increase and wide diffusion of naturalised productions in their new homes.

In a state of nature almost every plant produces seed, and amongst animals there are very few which do not annually pair. Hence we may confidently assert, that all plants and animals are tending to increase at a geometrical ratio, that all would most rapidly stock every station in which they could any how exist, and that the geometrical tendency to increase must be checked by destruction at some period of life. Our familiarity with the larger domestic animals tends, I think, to mislead us: we see no great destruction falling on them, and we forget that thousands are annually slaughtered for food, and that in a state of nature an equal number would have somehow to be disposed of.

The only difference between organisms which annually produce eggs or seeds by the thousand, and those which produce extremely few, is, that the slow-breeders would require a few more years to people, under favourable conditions, a whole district, let it be ever so large. The condor lays a couple of eggs and the ostrich a score, and yet in the same country the condor may be the more numerous of the two: the Fulmar petrel lays but one egg, yet it is believed to be the most numerous bird in the world. One fly deposits hundreds of eggs, and another, like the hippobosca, a single one; but this difference does not determine how many individuals of the two species can be supported in a district. A large number of eggs is of some importance to those species, which depend on a rapidly fluctuating amount of food, for it allows them rapidly to increase in number. But the real importance of a large number of eggs or seeds is to make up for much destruction at some period of life; and this period in the great majority of cases is an early one. If an animal can in any way protect its own eggs or young, a small number may be produced, and yet the average stock be fully kept up; but if many eggs or young are destroyed, many must be produced, or the species will become extinct. It would suffice to keep up the full number of a tree, which lived on an average for a thousand years, if a single seed were produced once in a thousand years, supposing that this seed were never destroyed, and could be ensured to germinate in a fitting place. So that in all cases, the average number of any animal or plant depends only indirectly on the number of its eggs or seeds.

In looking at Nature, it is most necessary to keep the foregoing considerations always in mind never to forget that every single organic being around us may be said to be striving to the utmost to increase in numbers; that each lives by a struggle at some period of its life; that heavy destruction inevitably falls either on the young or old, during each generation or at recurrent intervals. Lighten any check, mitigate the destruction ever so little, and the number of the species will almost instantaneously increase to any amount. The face of Nature may be compared to a yielding surface, with ten thousand sharp wedges packed close together and driven inwards by incessant blows, sometimes one wedge being struck, and then another with greater force.

What checks the natural tendency of each species to increase in number is most obscure. Look at the most vigorous species; by as much as it swarms in numbers, by so much will its tendency to increase be still further increased. We know not exactly what the checks are in even one single instance. Nor will this surprise any one who reflects how ignorant we are on this head, even in regard to mankind, so incomparably better known than any other animal. This subject has been ably treated by several authors, and I shall, in my future work, discuss some of the checks at considerable length, more especially in regard to the feral animals of South America. Here I will make only a few remarks, just to recall to the reader's mind some of the chief points. Eggs or very young animals seem generally to suffer most, but this is not invariably the case. With plants there is a vast destruction of seeds, but, from some observations which I have made, I believe that it is the seedlings which suffer most from germinating in ground already thickly stocked with other plants. Seedlings, also, are destroyed in vast numbers by various enemies; for instance, on a piece of ground three feet long and two wide, dug and cleared, and where there could be no choking from other plants, I marked all the seedlings of our native weeds as they came up, and out of the 357 no less than 295 were destroyed, chiefly by slugs and insects. If turf which has long been mown, and the case would be the same with turf closely browsed by quadrupeds, be let to grow, the more vigorous plants gradually kill the less vigorous, though fully grown, plants: thus out of twenty species growing on a little plot of turf (three feet by four) nine species perished from the other species being allowed to grow up freely.

The amount of food for each species of course gives the extreme limit to which each can increase; but very frequently it is not the obtaining food, but the serving as prey to other animals, which determines the average numbers of a species. Thus, there seems to be little doubt that the stock of partridges, grouse, and hares on any large estate depends chiefly on the destruction of vermin. If not one head of game were shot during the next twenty years in England, and, at the same time, if no vermin were destroyed, there would, in all probability, be less game than at present, although hundreds of thousands of game animals are now annually killed. On the other hand, in some cases, as with the elephant and rhinoceros, none are destroyed by beasts of prey: even the tiger in India most rarely dares to attack a young elephant protected by its dam.

Climate plays an important part in determining the average numbers of a species, and periodical seasons of extreme cold or drought, I believe to be the most effective of all checks. I estimated that the winter of 1854-55 destroyed four-fifths of the birds in my own grounds; and this is a tremendous destruction, when we remember that ten per cent. is an extraordinarily severe mortality from epidemics with man. The action of climate seems at first sight to be quite independent of the struggle for existence; but in so far as climate chiefly acts in reducing food, it brings on the most severe struggle between the individuals, whether of the same or of distinct species, which subsist on the same kind of food. Even when climate, for instance extreme cold, acts directly, it will be the least vigorous, or those which have got least food through the advancing winter, which will suffer most. When we travel from south to north, or from a damp region to a dry, we invariably see some species gradually getting rarer and rarer, and finally disappearing; and the change of climate being conspicuous, we are tempted to attribute the whole effect to its direct action. But this is a very false view: we forget that each species, even where it most abounds, is constantly suffering enormous destruction at some period of its life, from enemies or from competitors for the same place and food; and if these enemies or competitors be in the least degree favoured by any slight change of climate, they will increase in numbers, and, as each area is already fully stocked with inhabitants, the other species will decrease. When we travel southward and see a species decreasing in numbers, we may feel sure that the cause lies quite as much in other species being favoured, as in this one being hurt. So it is when we travel northward, but in a somewhat lesser degree, for the number of species of all kinds, and therefore of competitors, decreases northwards; hence in going northward, or in ascending a mountain, we far oftener meet with stunted forms, due to the directly injurious action of climate, than we do in proceeding southwards or in descending a mountain. When we reach the Arctic regions, or snow-capped summits, or absolute deserts, the struggle for life is almost exclusively with the elements.

That climate acts in main part indirectly by favouring other species, we may clearly see in the prodigious number of plants in our gardens which can perfectly well endure our climate, but which never become naturalised, for they cannot compete with our native plants, nor resist destruction by our native animals.

When a species, owing to highly favourable circumstances, increases inordinately in numbers in a small tract, epidemics at least, this seems generally to occur with our game animals often ensue: and here we have a limiting check independent of the struggle for life. But even some of these so-called epidemics appear to be due to parasitic worms, which have from some cause, possibly in part through facility of diffusion amongst the crowded animals, been disproportionably favoured: and here comes in a sort of struggle between the parasite and its prey.

On the other hand, in many cases, a large stock of individuals of the same species, relatively to the numbers of its enemies, is absolutely necessary for its preservation. Thus we can easily raise plenty of corn and rape-seed, &c., in our fields, because the seeds are in great excess compared with the number of birds which feed on them; nor can the birds, though having a superabundance of food at this one season, increase in number proportionally to the supply of seed, as their numbers are checked during winter: but any one who has tried, knows how troublesome it is to get seed from a few wheat or other such plants in a garden; I have in this case lost every single seed. This view of the necessity of a large stock of the same species for its preservation, explains, I believe, some singular facts in nature, such as that of very rare plants being sometimes extremely abundant in the few spots where they do occur; and that of some social plants being social, that is, abounding in individuals, even on the extreme confines of their range. For in such cases, we may believe, that a plant could exist only where the conditions of its life were so favourable that many could exist together, and thus save each other from utter destruction. I should add that the good effects of frequent intercrossing, and the ill effects of close interbreeding, probably come into play in some of these cases; but on this intricate subject I will not here enlarge.

Many cases are on record showing how complex and unexpected are the checks and relations between organic beings, which have to struggle together in the same country. I will give only a single instance, which, though a simple one, has interested me. In Staffordshire, on the estate of a relation where I had ample means of investigation, there was a large and extremely barren heath, which had never been touched by the hand of man; but several hundred acres of exactly the same nature had been enclosed twenty-five years previously and planted with Scotch fir. The change in the native vegetation of the planted part of the heath was most remarkable, more than is generally seen in passing from one quite different soil to another: not only the proportional numbers of the heath-plants were wholly changed, but twelve species of plants (not counting grasses and carices) flourished in the plantations, which could not be found on the heath. The effect on the insects must have been still greater, for six insectivorous birds were very common in the plantations, which were not to be seen on the heath; and the heath was frequented by two or three distinct insectivorous birds. Here we see how potent has been the effect of the introduction of a single tree, nothing whatever else having been done, with the exception that the land had been enclosed, so that cattle could not enter. But how important an element enclosure is, I plainly saw near Farnham, in Surrey. Here there are extensive heaths, with a few clumps of old Scotch firs on the distant hill-tops: within the last ten years large spaces have been enclosed, and self-sown firs are now springing up in multitudes, so close together that all cannot live. When I ascertained that these young trees had not been sown or planted, I was so much surprised at their numbers that I went to several points of view, whence I could examine hundreds of acres of the unenclosed heath, and literally I could not see a single Scotch fir, except the old planted clumps. But on looking closely between the stems of the heath, I found a multitude of seedlings and little trees, which had been perpetually browsed down by the cattle. In one square yard, at a point some hundreds yards distant from one of the old clumps, I counted thirty-two little trees; and one of them, judging from the rings of growth, had during twenty-six years tried to raise its head above the stems of the heath, and had failed. No wonder that, as soon as the land was enclosed, it became thickly clothed with vigorously growing young firs. Yet the heath was so extremely barren and so extensive that no one would ever have imagined that cattle would have so closely and effectually searched it for food.

Here we see that cattle absolutely determine the existence of the Scotch fir; but in several parts of the world insects determine the existence of cattle. Perhaps Paraguay offers the most curious instance of this; for here neither cattle nor horses nor dogs have ever run wild, though they swarm southward and northward in a feral state; and Azara and Rengger have shown that this is caused by the greater number in Paraguay of a certain fly, which lays its eggs in the navels of these animals when first born. The increase of these flies, numerous as they are, must be habitually checked by some means, probably by birds. Hence, if certain insectivorous birds (whose numbers are probably regulated by hawks or beasts of prey) were to increase in Paraguay, the flies would decrease then cattle and horses would become feral, and this would certainly greatly alter (as indeed I have observed in parts of South America) the vegetation: this again would largely affect the insects; and this, as we just have seen in Staffordshire, the insectivorous birds, and so onwards in ever-increasing circles of complexity. We began this series by insectivorous birds, and we have ended with them. Not that in nature the relations can ever be as simple as this. Battle within battle must ever be recurring with varying success; and yet in the long-run the forces are so nicely balanced, that the face of nature remains uniform for long periods of time, though assuredly the merest trifle would often give the victory to one organic being over another. Nevertheless so profound is our ignorance, and so high our presumption, that we marvel when we hear of the extinction of an organic being; and as we do not see the cause, we invoke cataclysms to desolate the world, or invent laws on the duration of the forms of life!

I am tempted to give one more instance showing how plants and animals, most remote in the scale of nature, are bound together by a web of complex relations. I shall hereafter have occasion to show that the exotic Lobelia fulgens, in this part of England, is never visited by insects, and consequently, from its peculiar structure, never can set a seed. Many of our orchidaceous plants absolutely require the visits of moths to remove their pollen-masses and thus to fertilise them. I have, also, reason to believe that humble-bees are indispensable to the fertilisation of the heartsease (Viola tricolor), for other bees do not visit this flower. From experiments which I have tried, I have found that the visits of bees, if not indispensable, are at least highly beneficial to the fertilisation of our clovers; but humble-bees alone visit the common red clover (Trifolium pratense), as other bees cannot reach the nectar. Hence I have very little doubt, that if the whole genus of humble-bees became extinct or very rare in England, the heartsease and red clover would become very rare, or wholly disappear. The number of humble-bees in any district depends in a great degree on the number of field-mice, which destroy their combs and nests; and Mr H. Newman, who has long attended to the habits of humble-bees, believes that 'more than two thirds of them are thus destroyed all over England.' Now the number of mice is largely dependent, as every one knows, on the number of cats; and Mr Newman says, 'Near villages and small towns I have found the nests of humble-bees more numerous than elsewhere, which I attribute to the number of cats that destroy the mice.' Hence it is quite credible that the presence of a feline animal in large numbers in a district might determine, through the intervention first of mice and then of bees, the frequency of certain flowers in that district!

In the case of every species, many different checks, acting at different periods of life, and during different seasons or years, probably come into play; some one check or some few being generally the most potent, but all concurring in determining the average number or even the existence of the species. In some cases it can be shown that widely-different checks act on the same species in different districts. When we look at the plants and bushes clothing an entangled bank, we are tempted to attribute their proportional numbers and kinds to what we call chance. But how false a view is this! Every one has heard that when an American forest is cut down, a very different vegetation springs up; but it has been observed that the trees now growing on the ancient Indian mounds, in the Southern United States, display the same beautiful diversity and proportion of kinds as in the surrounding virgin forests. What a struggle between the several kinds of trees must here have gone on during long centuries, each annually scattering its seeds by the thousand; what war between insect and insect between insects, snails, and other animals with birds and beasts of prey all striving to increase, and all feeding on each other or on the trees or their seeds and seedlings, or on the other plants which first clothed the ground and thus checked the growth of the trees! Throw up a handful of feathers, and all must fall to the ground according to definite laws; but how simple is this problem compared to the action and reaction of the innumerable plants and animals which have determined, in the course of centuries, the proportional numbers and kinds of trees now growing on the old Indian ruins!

The dependency of one organic being on another, as of a parasite on its prey, lies generally between beings remote in the scale of nature. This is often the case with those which may strictly be said to struggle with each other for existence, as in the case of locusts and grass-feeding quadrupeds. But the struggle almost invariably will be most severe between the individuals of the same species, for they frequent the same districts, require the same food, and are exposed to the same dangers. In the case of varieties of the same species, the struggle will generally be almost equally severe, and we sometimes see the contest soon decided: for instance, if several varieties of wheat be sown together, and the mixed seed be resown, some of the varieties which best suit the soil or climate, or are naturally the most fertile, will beat the others and so yield more seed, and will consequently in a few years quite supplant the other varieties. To keep up a mixed stock of even such extremely close varieties as the variously coloured sweet-peas, they must be each year harvested separately, and the seed then mixed in due proportion, otherwise the weaker kinds will steadily decrease in numbers and disappear. So again with the varieties of sheep: it has been asserted that certain mountain-varieties will starve out other mountain-varieties, so that they cannot be kept together. The same result has followed from keeping together different varieties of the medicinal leech. It may even be doubted whether the varieties of any one of our domestic plants or animals have so exactly the same strength, habits, and constitution, that the original proportions of a mixed stock could be kept up for half a dozen generations, if they were allowed to struggle together, like beings in a state of nature, and if the seed or young were not annually sorted.

As species of the same genus have usually, though by no means invariably, some similarity in habits and constitution, and always in structure, the struggle will generally be more severe between species of the same genus, when they come into competition with each other, than between species of distinct genera. We see this in the recent extension over parts of the United States of one species of swallow having caused the decrease of another species. The recent increase of the missel-thrush in parts of Scotland has caused the decrease of the song-thrush. How frequently we hear of one species of rat taking the place of another species under the most different climates! In Russia the small Asiatic cockroach has everywhere driven before it its great congener. One species of charlock will supplant another, and so in other cases. We can dimly see why the competition should be most severe between allied forms, which fill nearly the same place in the economy of nature; but probably in no one case could we precisely say why one species has been victorious over another in the great battle of life.

A corollary of the highest importance may be deduced from the foregoing remarks, namely, that the structure of every organic being is related, in the most essential yet often hidden manner, to that of all other organic beings, with which it comes into competition for food or residence, or from which it has to escape, or on which it preys. This is obvious in the structure of the teeth and talons of the tiger; and in that of the legs and claws of the parasite which clings to the hair on the tiger's body. But in the beautifully plumed seed of the dandelion, and in the flattened and fringed legs of the water-beetle, the relation seems at first confined to the elements of air and water. Yet the advantage of plumed seeds no doubt stands in the closest relation to the land being already thickly clothed by other plants; so that the seeds may be widely distributed and fall on unoccupied ground. In the water-beetle, the structure of its legs, so well adapted for diving, allows it to compete with other aquatic insects, to hunt for its own prey, and to escape serving as prey to other animals.

The store of nutriment laid up within the seeds of many plants seems at first sight to have no sort of relation to other plants. But from the strong growth of young plants produced from such seeds (as peas and beans), when sown in the midst of long grass, I suspect that the chief use of the nutriment in the seed is to favour the growth of the young seedling, whilst struggling with other plants growing vigorously all around.

Look at a plant in the midst of its range, why does it not double or quadruple its numbers? We know that it can perfectly well withstand a little more heat or cold, dampness or dryness, for elsewhere it ranges into slightly hotter or colder, damper or drier districts. In this case we can clearly see that if we wished in imagination to give the plant the power of increasing in number, we should have to give it some advantage over its competitors, or over the animals which preyed on it. On the confines of its geographical range, a change of constitution with respect to climate would clearly be an advantage to our plant; but we have reason to believe that only a few plants or animals range so far, that they are destroyed by the rigour of the climate alone. Not until we reach the extreme confines of life, in the arctic regions or on the borders of an utter desert, will competition cease. The land may be extremely cold or dry, yet there will be competition between some few species, or between the individuals of the same species, for the warmest or dampest spots.

Hence, also, we can see that when a plant or animal is placed in a new country amongst new competitors, though the climate may be exactly the same as in its former home, yet the conditions of its life will generally be changed in an essential manner. If we wished to increase its average numbers in its new home, we should have to modify it in a different way to what we should have done in its native country; for we should have to give it some advantage over a different set of competitors or enemies.

It is good thus to try in our imagination to give any form some advantage over another. Probably in no single instance should we know what to do, so as to succeed. It will convince us of our ignorance on the mutual relations of all organic beings; a conviction as necessary, as it seems to be difficult to acquire. All that we can do, is to keep steadily in mind that each organic being is striving to increase at a geometrical ratio; that each at some period of its life, during some season of the year, during each generation or at intervals, has to struggle for life, and to suffer great destruction. When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply. 
How will the struggle for existence, discussed too briefly in the last chapter, act in regard to variation? Can the principle of selection, which we have seen is so potent in the hands of man, apply in nature? I think we shall see that it can act most effectually. Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the, whole organisation becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favourable variations and the rejection of injurious variations, I call Natural Selection. Variations neither useful nor injurious would not be affected by natural selection, and would be left a fluctuating element, as perhaps we see in the species called polymorphic.

We shall best understand the probable course of natural selection by taking the case of a country undergoing some physical change, for instance, of climate. The proportional numbers of its inhabitants would almost immediately undergo a change, and some species might become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of some of the inhabitants, independently of the change of climate itself, would most seriously affect many of the others. If the country were open on its borders, new forms would certainly immigrate, and this also would seriously disturb the relations of some of the former inhabitants. Let it be remembered how powerful the influence of a single introduced tree or mammal has been shown to be. But in the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such case, every slight modification, which in the course of ages chanced to arise, and which in any way favoured the individuals of any of the species, by better adapting them to their altered conditions, would tend to be preserved; and natural selection would thus have free scope for the work of improvement.

We have reason to believe, as stated in the first chapter, that a change in the conditions of life, by specially acting on the reproductive system, causes or increases variability; and in the foregoing case the conditions of life are supposed to have undergone a change, and this would manifestly be favourable to natural selection, by giving a better chance of profitable variations occurring; and unless profitable variations do occur, natural selection can do nothing. Not that, as I believe, any extreme amount of variability is necessary; as man can certainly produce great results by adding up in any given direction mere individual differences, so could Nature, but far more easily, from having incomparably longer time at her disposal. Nor do I believe that any great physical change, as of climate, or any unusual degree of isolation to check immigration, is actually necessary to produce new and unoccupied places for natural selection to fill up by modifying and improving some of the varying inhabitants. For as all the inhabitants of each country are struggling together with nicely balanced forces, extremely slight modifications in the structure or habits of one inhabitant would often give it an advantage over others; and still further modifications of the same kind would often still further increase the advantage. No country can be named in which all the native inhabitants are now so perfectly adapted to each other and to the physical conditions under which they live, that none of them could anyhow be improved; for in all countries, the natives have been so far conquered by naturalised productions, that they have allowed foreigners to take firm possession of the land. And as foreigners have thus everywhere beaten some of the natives, we may safely conclude that the natives might have been modified with advantage, so as to have better resisted such intruders.

As man can produce and certainly has produced a great result by his methodical and unconscious means of selection, what may not nature effect? Man can act only on external and visible characters: nature cares nothing for appearances, except in so far as they may be useful to any being. She can act on every internal organ, on every shade of constitutional difference, on the whole machinery of life. Man selects only for his own good; Nature only for that of the being which she tends. Every selected character is fully exercised by her; and the being is placed under well-suited conditions of life. Man keeps the natives of many climates in the same country; he seldom exercises each selected character in some peculiar and fitting manner; he feeds a long and a short beaked pigeon on the same food; he does not exercise a long-backed or long-legged quadruped in any peculiar manner; he exposes sheep with long and short wool to the same climate. He does not allow the most vigorous males to struggle for the females. He does not rigidly destroy all inferior animals, but protects during each varying season, as far as lies in his power, all his productions. He often begins his selection by some half-monstrous form; or at least by some modification prominent enough to catch his eye, or to be plainly useful to him. Under nature, the slightest difference of structure or constitution may well turn the nicely-balanced scale in the struggle for life, and so be preserved. How fleeting are the wishes and efforts of man! how short his time! and consequently how poor will his products be, compared with those accumulated by nature during whole geological periods. Can we wonder, then, that nature's productions should be far 'truer' in character than man's productions; that they should be infinitely better adapted to the most complex conditions of life, and should plainly bear the stamp of far higher workmanship?

It may be said that natural selection is daily and hourly scrutinising, throughout the world, every variation, even the slightest; rejecting that which is bad, preserving and adding up all that is good; silently and insensibly working, whenever and wherever opportunity offers, at the improvement of each organic being in relation to its organic and inorganic conditions of life. We see nothing of these slow changes in progress, until the hand of time has marked the long lapses of ages, and then so imperfect is our view into long past geological ages, that we only see that the forms of life are now different from what they formerly were.

Although natural selection can act only through and for the good of each being, yet characters and structures, which we are apt to consider as of very trifling importance, may thus be acted on. When we see leaf-eating insects green, and bark-feeders mottled-grey; the alpine ptarmigan white in winter, the red-grouse the colour of heather, and the black-grouse that of peaty earth, we must believe that these tints are of service to these birds and insects in preserving them from danger. Grouse, if not destroyed at some period of their lives, would increase in countless numbers; they are known to suffer largely from birds of prey; and hawks are guided by eyesight to their prey, so much so, that on parts of the Continent persons are warned not to keep white pigeons, as being the most liable to destruction. Hence I can see no reason to doubt that natural selection might be most effective in giving the proper colour to each kind of grouse, and in keeping that colour, when once acquired, true and constant. Nor ought we to think that the occasional destruction of an animal of any particular colour would produce little effect: we should remember how essential it is in a flock of white sheep to destroy every lamb with the faintest trace of black. In plants the down on the fruit and the colour of the flesh are considered by botanists as characters of the most trifling importance: yet we hear from an excellent horticulturist, Downing, that in the United States smooth-skinned fruits suffer far more from a beetle, a curculio, than those with down; that purple plums suffer far more from a certain disease than yellow plums; whereas another disease attacks yellow-fleshed peaches far more than those with other coloured flesh. If, with all the aids of art, these slight differences make a great difference in cultivating the several varieties, assuredly, in a state of nature, where the trees would have to struggle with other trees and with a host of enemies, such differences would effectually settle which variety, whether a smooth or downy, a yellow or purple fleshed fruit, should succeed.

In looking at many small points of difference between species, which, as far as our ignorance permits us to judge, seem to be quite unimportant, we must not forget that climate, food, &c., probably produce some slight and direct effect. It is, however, far more necessary to bear in mind that there are many unknown laws of correlation of growth, which, when one part of the organisation is modified through variation, and the modifications are accumulated by natural selection for the good of the being, will cause other modifications, often of the most unexpected nature.

As we see that those variations which under domestication appear at any particular period of life, tend to reappear in the offspring at the same period; for instance, in the seeds of the many varieties of our culinary and agricultural plants; in the caterpillar and cocoon stages of the varieties of the silkworm; in the eggs of poultry, and in the colour of the down of their chickens; in the horns of our sheep and cattle when nearly adult; so in a state of nature, natural selection will be enabled to act on and modify organic beings at any age, by the accumulation of profitable variations at that age, and by their inheritance at a corresponding age. If it profit a plant to have its seeds more and more widely disseminated by the wind, I can see no greater difficulty in this being effected through natural selection, than in the cotton-planter increasing and improving by selection the down in the pods on his cotton-trees. Natural selection may modify and adapt the larva of an insect to a score of contingencies, wholly different from those which concern the mature insect. These modifications will no doubt affect, through the laws of correlation, the structure of the adult; and probably in the case of those insects which live only for a few hours, and which never feed, a large part of their structure is merely the correlated result of successive changes in the structure of their larvae. So, conversely, modifications in the adult will probably often affect the structure of the larva; but in all cases natural selection will ensure that modifications consequent on other modifications at a different period of life, shall not be in the least degree injurious: for if they became so, they would cause the extinction of the species.

Natural selection will modify the structure of the young in relation to the parent, and of the parent in relation to the young. In social animals it will adapt the structure of each individual for the benefit of the community; if each in consequence profits by the selected change. What natural selection cannot do, is to modify the structure of one species, without giving it any advantage, for the good of another species; and though statements to this effect may be found in works of natural history, I cannot find one case which will bear investigation. A structure used only once in an animal's whole life, if of high importance to it, might be modified to any extent by natural selection; for instance, the great jaws possessed by certain insects, and used exclusively for opening the cocoon or the hard tip to the beak of nestling birds, used for breaking the egg. It has been asserted, that of the best short-beaked tumbler-pigeons more perish in the egg than are able to get out of it; so that fanciers assist in the act of hatching. Now, if nature had to make the beak of a full-grown pigeon very short for the bird's own advantage, the process of modification would be very slow, and there would be simultaneously the most rigorous selection of the young birds within the egg, which had the most powerful and hardest beaks, for all with weak beaks would inevitably perish: or, more delicate and more easily broken shells might be selected, the thickness of the shell being known to vary like every other structure.

Sexual Selection

Inasmuch as peculiarities often appear under domestication in one sex and become hereditarily attached to that sex, the same fact probably occurs under nature, and if so, natural selection will be able to modify one sex in its functional relations to the other sex, or in relation to wholly different habits of life in the two sexes, as is sometimes the case with insects. And this leads me to say a few words on what I call Sexual Selection. This depends, not on a struggle for existence, but on a struggle between the males for possession of the females; the result is not death to the unsuccessful competitor, but few or no offspring. Sexual selection is, therefore, less rigorous than natural selection. Generally, the most vigorous males, those which are best fitted for their places in nature, will leave most progeny. But in many cases, victory will depend not on general vigour, but on having special weapons, confined to the male sex. A hornless stag or spurless cock would have a poor chance of leaving offspring. Sexual selection by always allowing the victor to breed might surely give indomitable courage, length to the spur, and strength to the wing to strike in the spurred leg, as well as the brutal cock-fighter, who knows well that he can improve his breed by careful selection of the best cocks. How low in the scale of nature this law of battle descends, I know not; male alligators have been described as fighting, bellowing, and whirling round, like Indians in a war-dance, for the possession of the females; male salmons have been seen fighting all day long; male stag-beetles often bear wounds from the huge mandibles of other males. The war is, perhaps, severest between the males of polygamous animals, and these seem oftenest provided with special weapons. The males of carnivorous animals are already well armed; though to them and to others, special means of defence may be given through means of sexual selection, as the mane to the lion, the shoulder-pad to the boar, and the hooked jaw to the male salmon; for the shield may be as important for victory, as the sword or spear.

Amongst birds, the contest is often of a more peaceful character. All those who have attended to the subject, believe that there is the severest rivalry between the males of many species to attract by singing the females. The rock-thrush of Guiana, birds of paradise, and some others, congregate; and successive males display their gorgeous plumage and perform strange antics before the females, which standing by as spectators, at last choose the most attractive partner. Those who have closely attended to birds in confinement well know that they often take individual preferences and dislikes: thus Sir R. Heron has described how one pied peacock was eminently attractive to all his hen birds. It may appear childish to attribute any effect to such apparently weak means: I cannot here enter on the details necessary to support this view; but if man can in a short time give elegant carriage and beauty to his bantams, according to his standard of beauty, I can see no good reason to doubt that female birds, by selecting, during thousands of generations, the most melodious or beautiful males, according to their standard of beauty, might produce a marked effect. I strongly suspect that some well-known laws with respect to the plumage of male and female birds, in comparison with the plumage of the young, can be explained on the view of plumage having been chiefly modified by sexual selection, acting when the birds have come to the breeding age or during the breeding season; the modifications thus produced being inherited at corresponding ages or seasons, either by the males alone, or by the males and females; but I have not space here to enter on this subject.

Thus it is, as I believe, that when the males and females of any animal have the same general habits of life, but differ in structure, colour, or ornament, such differences have been mainly caused by sexual selection; that is, individual males have had, in successive generations, some slight advantage over other males, in their weapons, means of defence, or charms; and have transmitted these advantages to their male offspring. Yet, I would not wish to attribute all such sexual differences to this agency: for we see peculiarities arising and becoming attached to the male sex in our domestic animals (as the wattle in male carriers, horn-like protuberances in the cocks of certain fowls, &c.), which we cannot believe to be either useful to the males in battle, or attractive to the females. We see analogous cases under nature, for instance, the tuft of hair on the breast of the turkey-cock, which can hardly be either useful or ornamental to this bird; indeed, had the tuft appeared under domestication, it would have been called a monstrosity.

Illustrations of the action of Natural Selection

In order to make it clear how, as I believe, natural selection acts, I must beg permission to give one or two imaginary illustrations. Let us take the case of a wolf, which preys on various animals, securing some by craft, some by strength, and some by fleetness; and let us suppose that the fleetest prey, a deer for instance, had from any change in the country increased in numbers, or that other prey had decreased in numbers, during that season of the year when the wolf is hardest pressed for food. I can under such circumstances see no reason to doubt that the swiftest and slimmest wolves would have the best chance of surviving, and so be preserved or selected, provided always that they retained strength to master their prey at this or at some other period of the year, when they might be compelled to prey on other animals. I can see no more reason to doubt this, than that man can improve the fleetness of his greyhounds by careful and methodical selection, or by that unconscious selection which results from each man trying to keep the best dogs without any thought of modifying the breed.

Even without any change in the proportional numbers of the animals on which our wolf preyed, a cub might be born with an innate tendency to pursue certain kinds of prey. Nor can this be thought very improbable; for we often observe great differences in the natural tendencies of our domestic animals; one cat, for instance, taking to catch rats, another mice; one cat, according to Mr. St. John, bringing home winged game, another hares or rabbits, and another hunting on marshy ground and almost nightly catching woodcocks or snipes. The tendency to catch rats rather than mice is known to be inherited. Now, if any slight innate change of habit or of structure benefited an individual wolf, it would have the best chance of surviving and of leaving offspring. Some of its young would probably inherit the same habits or structure, and by the repetition of this process, a new variety might be formed which would either supplant or coexist with the parent-form of wolf. Or, again, the wolves inhabiting a mountainous district, and those frequenting the lowlands, would naturally be forced to hunt different prey; and from the continued preservation of the individuals best fitted for the two sites, two varieties might slowly be formed. These varieties would cross and blend where they met; but to this subject of intercrossing we shall soon have to return. I may add, that, according to Mr. Pierce, there are two varieties of the wolf inhabiting the Catskill Mountains in the United States, one with a light greyhound-like form, which pursues deer, and the other more bulky, with shorter legs, which more frequently attacks the shepherd's flocks.

Let us now take a more complex case. Certain plants excrete a sweet juice, apparently for the sake of eliminating something injurious from their sap: this is effected by glands at the base of the stipules in some Leguminosae, and at the back of the leaf of the common laurel. This juice, though small in quantity, is greedily sought by insects. Let us now suppose a little sweet juice or nectar to be excreted by the inner bases of the petals of a flower. In this case insects in seeking the nectar would get dusted with pollen, and would certainly often transport the pollen from one flower to the stigma of another flower. The flowers of two distinct individuals of the same species would thus get crossed; and the act of crossing, we have good reason to believe (as will hereafter be more fully alluded to), would produce very vigorous seedlings, which consequently would have the best chance of flourishing and surviving. Some of these seedlings would probably inherit the nectar-excreting power. Those in individual flowers which had the largest glands or nectaries, and which excreted most nectar, would be oftenest visited by insects, and would be oftenest crossed; and so in the long-run would gain the upper hand. Those flowers, also, which had their stamens and pistils placed, in relation to the size and habits of the particular insects which visited them, so as to favour in any degree the transportal of their pollen from flower to flower, would likewise be favoured or selected. We might have taken the case of insects visiting flowers for the sake of collecting pollen instead of nectar; and as pollen is formed for the sole object of fertilisation, its destruction appears a simple loss to the plant; yet if a little pollen were carried, at first occasionally and then habitually, by the pollen-devouring insects from flower to flower, and a cross thus effected, although nine-tenths of the pollen were destroyed, it might still be a great gain to the plant; and those individuals which produced more and more pollen, and had larger and larger anthers, would be selected.

When our plant, by this process of the continued preservation or natural selection of more and more attractive flowers, had been rendered highly attractive to insects, they would, unintentionally on their part, regularly carry pollen from flower to flower; and that they can most effectually do this, I could easily show by many striking instances. I will give only one not as a very striking case, but as likewise illustrating one step in the separation of the sexes of plants, presently to be alluded to. Some holly-trees bear only male flowers, which have four stamens producing rather a small quantity of pollen, and a rudimentary pistil; other holly-trees bear only female flowers; these have a full-sized pistil, and four stamens with shrivelled anthers, in which not a grain of pollen can be detected. Having found a female tree exactly sixty yards from a male tree, I put the stigmas of twenty flowers, taken from different branches, under the microscope, and on all, without exception, there were pollen-grains, and on some a profusion of pollen. As the wind had set for several days from the female to the male tree, the pollen could not thus have been carried. The weather had been cold and boisterous, and therefore not favourable to bees, nevertheless every female flower which I examined had been effectually fertilised by the bees, accidentally dusted with pollen, having flown from tree to tree in search of nectar. But to return to our imaginary case: as soon as the plant had been rendered so highly attractive to insects that pollen was regularly carried from flower to flower, another process might commence. No naturalist doubts the advantage of what has been called the 'physiological division of labour;' hence we may believe that it would be advantageous to a plant to produce stamens alone in one flower or on one whole plant, and pistils alone in another flower or on another plant. In plants under culture and placed under new conditions of life, sometimes the male organs and sometimes the female organs become more or less impotent; now if we suppose this to occur in ever so slight a degree under nature, then as pollen is already carried regularly from flower to flower, and as a more complete separation of the sexes of our plant would be advantageous on the principle of the division of labour, individuals with this tendency more and more increased, would be continually favoured or selected, until at last a complete separation of the sexes would be effected.

Let us now turn to the nectar-feeding insects in our imaginary case: we may suppose the plant of which we have been slowly increasing the nectar by continued selection, to be a common plant; and that certain insects depended in main part on its nectar for food. I could give many facts, showing how anxious bees are to save time; for instance, their habit of cutting holes and sucking the nectar at the bases of certain flowers, which they can, with a very little more trouble, enter by the mouth. Bearing such facts in mind, I can see no reason to doubt that an accidental deviation in the size and form of the body, or in the curvature and length of the proboscis, &c., far too slight to be appreciated by us, might profit a bee or other insect, so that an individual so characterised would be able to obtain its food more quickly, and so have a better chance of living and leaving descendants. Its descendants would probably inherit a tendency to a similar slight deviation of structure. The tubes of the corollas of the common red and incarnate clovers (Trifolium pratense and incarnatum) do not on a hasty glance appear to differ in length; yet the hive-bee can easily suck the nectar out of the incarnate clover, but not out of the common red clover, which is visited by humble-bees alone; so that whole fields of the red clover offer in vain an abundant supply of precious nectar to the hive-bee. Thus it might be a great advantage to the hive-bee to have a slightly longer or differently constructed proboscis. On the other hand, I have found by experiment that the fertility of clover greatly depends on bees visiting and moving parts of the corolla, so as to push the pollen on to the stigmatic surface. Hence, again, if humble-bees were to become rare in any country, it might be a great advantage to the red clover to have a shorter or more deeply divided tube to its corolla, so that the hive-bee could visit its flowers. Thus I can understand how a flower and a bee might slowly become, either simultaneously or one after the other, modified and adapted in the most perfect manner to each other, by the continued preservation of individuals presenting mutual and slightly favourable deviations of structure.

I am well aware that this doctrine of natural selection, exemplified in the above imaginary instances, is open to the same objections which were at first urged against Sir Charles Lyell's noble views on 'the modern changes of the earth, as illustrative of geology;' but we now very seldom hear the action, for instance, of the coast-waves, called a trifling and insignificant cause, when applied to the excavation of gigantic valleys or to the formation of the longest lines of inland cliffs. Natural selection can act only by the preservation and accumulation of infinitesimally small inherited modifications, each profitable to the preserved being; and as modern geology has almost banished such views as the excavation of a great valley by a single diluvial wave, so will natural selection, if it be a true principle, banish the belief of the continued creation of new organic beings, or of any great and sudden modification in their structure.

On the Intercrossing of Individuals

I must here introduce a short digression. In the case of animals and plants with separated sexes, it is of course obvious that two individuals must always unite for each birth; but in the case of hermaphrodites this is far from obvious. Nevertheless I am strongly inclined to believe that with all hermaphrodites two individuals, either occasionally or habitually, concur for the reproduction of their kind. This view, I may add, was first suggested by Andrew Knight. We shall presently see its importance; but I must here treat the subject with extreme brevity, though I have the materials prepared for an ample discussion. All vertebrate animals, all insects, and some other large groups of animals, pair for each birth. Modern research has much diminished the number of supposed hermaphrodites, and of real hermaphrodites a large number pair; that is, two individuals regularly unite for reproduction, which is all that concerns us. But still there are many hermaphrodite animals which certainly do not habitually pair, and a vast majority of plants are hermaphrodites. What reason, it may be asked, is there for supposing in these cases that two individuals ever concur in reproduction? As it is impossible here to enter on details, I must trust to some general considerations alone.

In the first place, I have collected so large a body of facts, showing, in accordance with the almost universal belief of breeders, that with animals and plants a cross between different varieties, or between individuals of the same variety but of another strain, gives vigour and fertility to the offspring; and on the other hand, that close interbreeding diminishes vigour and fertility; that these facts alone incline me to believe that it is a general law of nature (utterly ignorant though we be of the meaning of the law) that no organic being self-fertilises itself for an eternity of generations; but that a cross with another individual is occasionally perhaps at very long intervals -- indispensable.

On the belief that this is a law of nature, we can, I think, understand several large classes of facts, such as the following, which on any other view are inexplicable. Every hybridizer knows how unfavourable exposure to wet is to the fertilisation of a flower, yet what a multitude of flowers have their anthers and stigmas fully exposed to the weather! but if an occasional cross be indispensable, the fullest freedom for the entrance of pollen from another individual will explain this state of exposure, more especially as the plant's own anthers and pistil generally stand so close together that self-fertilisation seems almost inevitable. Many flowers, on the other hand, have their organs of fructification closely enclosed, as in the great papilionaceous or pea-family; but in several, perhaps in all, such flowers, there is a very curious adaptation between the structure of the flower and the manner in which bees suck the nectar; for, in doing this, they either push the flower's own pollen on the stigma, or bring pollen from another flower. So necessary are the visits of bees to papilionaceous flowers, that I have found, by experiments published elsewhere, that their fertility is greatly diminished if these visits be prevented. Now, it is scarcely possible that bees should fly from flower to flower, and not carry pollen from one to the other, to the great good, as I believe, of the plant. Bees will act like a camel-hair pencil, and it is quite sufficient just to touch the anthers of one flower and then the stigma of another with the same brush to ensure fertilisation; but it must not be supposed that bees would thus produce a multitude of hybrids between distinct species; for if you bring on the same brush a plant's own pollen and pollen from another species, the former will have such a prepotent effect, that it will invariably and completely destroy, as has been shown by Gärtner, any influence from the foreign pollen.

When the stamens of a flower suddenly spring towards the pistil, or slowly move one after the other towards it, the contrivance seems adapted solely to ensure self-fertilisation; and no doubt it is useful for this end: but, the agency of insects is often required to cause the stamens to spring forward, as Kölreuter has shown to be the case with the barberry; and curiously in this very genus, which seems to have a special contrivance for self-fertilisation, it is well known that if very closely-allied forms or varieties are planted near each other, it is hardly possible to raise pure seedlings, so largely do they naturally cross. In many other cases, far from there being any aids for self-fertilisation, there are special contrivances, as I could show from the writings of C. C. Sprengel and from my own observations, which effectually prevent the stigma receiving pollen from its own flower: for instance, in Lobelia fulgens, there is a really beautiful and elaborate contrivance by which every one of the infinitely numerous pollen-granules are swept out of the conjoined anthers of each flower, before the stigma of that individual flower is ready to receive them; and as this flower is never visited, at least in my garden, by insects, it never sets a seed, though by placing pollen from one flower on the stigma of another, I raised plenty of seedlings; and whilst another species of Lobelia growing close by, which is visited by bees, seeds freely. In very many other cases, though there be no special mechanical contrivance to prevent the stigma of a flower receiving its own pollen, yet, as C. C. Sprengel has shown, and as I can confirm, either the anthers burst before the stigma is ready for fertilisation, or the stigma is ready before the pollen of that flower is ready, so that these plants have in fact separated sexes, and must habitually be crossed. How strange are these facts! How strange that the pollen and stigmatic surface of the same flower, though placed so close together, as if for the very purpose of self-fertilisation, should in so many cases be mutually useless to each other! How simply are these facts explained on the view of an occasional cross with a distinct individual being advantageous or indispensable!

If several varieties of the cabbage, radish, onion, and of some other plants, be allowed to seed near each other, a large majority, as I have found, of the seedlings thus raised will turn out mongrels: for instance, I raised 233 seedling cabbages from some plants of different varieties growing near each other, and of these only 78 were true to their kind, and some even of these were not perfectly true. Yet the pistil of each cabbage-flower is surrounded not only by its own six stamens, but by those of the many other flowers on the same plant. How, then, comes it that such a vast number of the seedlings are mongrelised? I suspect that it must arise from the pollen of a distinct variety having a prepotent effect over a flower's own pollen; and that this is part of the general law of good being derived from the intercrossing of distinct individuals of the same species. When distinct species are crossed the case is directly the reverse, for a plant's own pollen is always prepotent over foreign pollen; but to this subject we shall return in a future chapter.

In the case of a gigantic tree covered with innumerable flowers, it may be objected that pollen could seldom be carried from tree to tree, and at most only from flower to flower on the same tree, and that flowers on the same tree can be considered as distinct individuals only in a limited sense. I believe this objection to be valid, but that nature has largely provided against it by giving to trees a strong tendency to bear flowers with separated sexes. When the sexes are separated, although the male and female flowers may be produced on the same tree, we can see that pollen must be regularly carried from flower to flower; and this will give a better chance of pollen being occasionally carried from tree to tree. That trees belonging to all Orders have their sexes more often separated than other plants, I find to be the case in this country; and at my request Dr Hooker tabulated the trees of New Zealand, and Dr Asa Gray those of the United States, and the result was as I anticipated. On the other hand, Dr Hooker has recently informed me that he finds that the rule does not hold in Australia; and I have made these few remarks on the sexes of trees simply to call attention to the subject.

Turning for a very brief space to animals: on the land there are some hermaphrodites, as land-mollusca and earth-worms; but these all pair. As yet I have not found a single case of a terrestrial animal which fertilises itself. We can understand this remarkable fact, which offers so strong a contrast with terrestrial plants, on the view of an occasional cross being indispensable, by considering the medium in which terrestrial animals live, and the nature of the fertilising element; for we know of no means, analogous to the action of insects and of the wind in the case of plants, by which an occasional cross could be effected with terrestrial animals without the concurrence of two individuals. Of aquatic animals, there are many self-fertilising hermaphrodites; but here currents in the water offer an obvious means for an occasional cross. And, as in the case of flowers, I have as yet failed, after consultation with one of the highest authorities, namely, Professor Huxley, to discover a single case of an hermaphrodite animal with the organs of reproduction so perfectly enclosed within the body, that access from without and the occasional influence of a distinct individual can be shown to be physically impossible. Cirripedes long appeared to me to present a case of very great difficulty under this point of view; but I have been enabled, by a fortunate chance, elsewhere to prove that two individuals, though both are self-fertilising hermaphrodites, do sometimes cross.

It must have struck most naturalists as a strange anomaly that, in the case of both animals and plants, species of the same family and even of the same genus, though agreeing closely with each other in almost their whole organisation, yet are not rarely, some of them hermaphrodites, and some of them unisexual. But if, in fact, all hermaphrodites do occasionally intercross with other individuals, the difference between hermaphrodites and unisexual species, as far as function is concerned, becomes very small.

From these several considerations and from the many special facts which I have collected, but which I am not here able to give, I am strongly inclined to suspect that, both in the vegetable and animal kingdoms, an occasional intercross with a distinct individual is a law of nature. I am well aware that there are, on this view, many cases of difficulty, some of which I am trying to investigate. Finally then, we may conclude that in many organic beings, a cross between two individuals is an obvious necessity for each birth; in many others it occurs perhaps only at long intervals; but in none, as I suspect, can self-fertilisation go on for perpetuity.

Circumstances favourable to Natural Selection

This is an extremely intricate subject. A large amount of inheritable and diversified variability is favourable, but I believe mere individual differences suffice for the work. A large number of individuals, by giving a better chance for the appearance within any given period of profitable variations, will compensate for a lesser amount of variability in each individual, and is, I believe, an extremely important element of success. Though nature grants vast periods of time for the work of natural selection, she does not grant an indefinite period; for as all organic beings are striving, it may be said, to seize on each place in the economy of nature, if any one species does not become modified and improved in a corresponding degree with its competitors, it will soon be exterminated.

In man's methodical selection, a breeder selects for some definite object, and free intercrossing will wholly stop his work. But when many men, without intending to alter the breed, have a nearly common standard of perfection, and all try to get and breed from the best animals, much improvement and modification surely but slowly follow from this unconscious process of selection, notwithstanding a large amount of crossing with inferior animals. Thus it will be in nature; for within a confined area, with some place in its polity not so perfectly occupied as might be, natural selection will always tend to preserve all the individuals varying in the right direction, though in different degrees, so as better to fill up the unoccupied place. But if the area be large, its several districts will almost certainly present different conditions of life; and then if natural selection be modifying and improving a species in the several districts, there will be intercrossing with the other individuals of the same species on the confines of each. And in this case the effects of intercrossing can hardly be counterbalanced by natural selection always tending to modify all the individuals in each district in exactly the same manner to the conditions of each; for in a continuous area, the conditions will generally graduate away insensibly from one district to another. The intercrossing will most affect those animals which unite for each birth, which wander much, and which do not breed at a very quick rate. Hence in animals of this nature, for instance in birds, varieties will generally be confined to separated countries; and this I believe to be the case. In hermaphrodite organisms which cross only occasionally, and likewise in animals which unite for each birth, but which wander little and which can increase at a very rapid rate, a new and improved variety might be quickly formed on any one spot, and might there maintain itself in a body, so that whatever intercrossing took place would be chiefly between the individuals of the same new variety. A local variety when once thus formed might subsequently slowly spread to other districts. On the above principle, nurserymen always prefer getting seed from a large body of plants of the same variety, as the chance of intercrossing with other varieties is thus lessened.

Even in the case of slow-breeding animals, which unite for each birth, we must not overrate the effects of intercrosses in retarding natural selection; for I can bring a considerable catalogue of facts, showing that within the same area, varieties of the same animal can long remain distinct, from haunting different stations, from breeding at slightly different seasons, or from varieties of the same kind preferring to pair together.

Intercrossing plays a very important part in nature in keeping the individuals of the same species, or of the same variety, true and uniform in character. It will obviously thus act far more efficiently with those animals which unite for each birth; but I have already attempted to show that we have reason to believe that occasional intercrosses take place with all animals and with all plants. Even if these take place only at long intervals, I am convinced that the young thus produced will gain so much in vigour and fertility over the offspring from long-continued self-fertilisation, that they will have a better chance of surviving and propagating their kind; and thus, in the long run, the influence of intercrosses, even at rare intervals, will be great. If there exist organic beings which never intercross, uniformity of character can be retained amongst them, as long as their conditions of life remain the same, only through the principle of inheritance, and through natural selection destroying any which depart from the proper type; but if their conditions of life change and they undergo modification, uniformity of character can be given to their modified offspring, solely by natural selection preserving the same favourable variations.

Isolation, also, is an important element in the process of natural selection. In a confined or isolated area, if not very large, the organic and inorganic conditions of life will generally be in a great degree uniform; so that natural selection will tend to modify all the individuals of a varying species throughout the area in the same manner in relation to the same conditions. Intercrosses, also, with the individuals of the same species, which otherwise would have inhabited the surrounding and differently circumstanced districts, will be prevented. But isolation probably acts more efficiently in checking the immigration of better adapted organisms, after any physical change, such as of climate or elevation of the land, &c.; and thus new places in the natural economy of the country are left open for the old inhabitants to struggle for, and become adapted to, through modifications in their structure and constitution. Lastly, isolation, by checking immigration and consequently competition, will give time for any new variety to be slowly improved; and this may sometimes be of importance in the production of new species. If, however, an isolated area be very small, either from being surrounded by barriers, or from having very peculiar physical conditions, the total number of the individuals supported on it will necessarily be very small; and fewness of individuals will greatly retard the production of new species through natural selection, by decreasing the chance of the appearance of favourable variations.

If we turn to nature to test the truth of these remarks, and look at any small isolated area, such as an oceanic island, although the total number of the species inhabiting it, will be found to be small, as we shall see in our chapter on geographical distribution; yet of these species a very large proportion are endemic, that is, have been produced there, and nowhere else. Hence an oceanic island at first sight seems to have been highly favourable for the production of new species. But we may thus greatly deceive ourselves, for to ascertain whether a small isolated area, or a large open area like a continent, has been most favourable for the production of new organic forms, we ought to make the comparison within equal times; and this we are incapable of doing.

Although I do not doubt that isolation is of considerable importance in the production of new species, on the whole I am inclined to believe that largeness of area is of more importance, more especially in the production of species, which will prove capable of enduring for a long period, and of spreading widely. Throughout a great and open area, not only will there be a better chance of favourable variations arising from the large number of individuals of the same species there supported, but the conditions of life are infinitely complex from the large number of already existing species; and if some of these many species become modified and improved, others will have to be improved in a corresponding degree or they will be exterminated. Each new form, also, as soon as it has been much improved, will be able to spread over the open and continuous area, and will thus come into competition with many others. Hence more new places will be formed, and the competition to fill them will be more severe, on a large than on a small and isolated area. Moreover, great areas, though now continuous, owing to oscillations of level, will often have recently existed in a broken condition, so that the good effects of isolation will generally, to a certain extent, have concurred. Finally, I conclude that, although small isolated areas probably have been in some respects highly favourable for the production of new species, yet that the course of modification will generally have been more rapid on large areas; and what is more important, that the new forms produced on large areas, which already have been victorious over many competitors, will be those that will spread most widely, will give rise to most new varieties and species, and will thus play an important part in the changing history of the organic world.

We can, perhaps, on these views, understand some facts which will be again alluded to in our chapter on geographical distribution; for instance, that the productions of the smaller continent of Australia have formerly yielded, and apparently are now yielding, before those of the larger Europaeo-Asiatic area. Thus, also, it is that continental productions have everywhere become so largely naturalised on islands. On a small island, the race for life will have been less severe, and there will have been less modification and less extermination. Hence, perhaps, it comes that the flora of Madeira, according to Oswald Heer, resembles the extinct tertiary flora of Europe. All fresh-water basins, taken together, make a small area compared with that of the sea or of the land; and, consequently, the competition between fresh-water productions will have been less severe than elsewhere; new forms will have been more slowly formed, and old forms more slowly exterminated. And it is in fresh water that we find seven genera of Ganoid fishes, remnants of a once preponderant order: and in fresh water we find some of the most anomalous forms now known in the world, as the Ornithorhynchus and Lepidosiren, which, like fossils, connect to a certain extent orders now widely separated in the natural scale. These anomalous forms may almost be called living fossils; they have endured to the present day, from having inhabited a confined area, and from having thus been exposed to less severe competition.

To sum up the circumstances favourable and unfavourable to natural selection, as far as the extreme intricacy of the subject permits. I conclude, looking to the future, that for terrestrial productions a large continental area, which will probably undergo many oscillations of level, and which consequently will exist for long periods in a broken condition, will be the most favourable for the production of many new forms of life, likely to endure long and to spread widely. For the area will first have existed as a continent, and the inhabitants, at this period numerous in individuals and kinds, will have been subjected to very severe competition. When converted by subsidence into large separate islands, there will still exist many individuals of the same species on each island: intercrossing on the confines of the range of each species will thus be checked: after physical changes of any kind, immigration will be prevented, so that new places in the polity of each island will have to be filled up by modifications of the old inhabitants; and time will be allowed for the varieties in each to become well modified and perfected. When, by renewed elevation, the islands shall be re-converted into a continental area, there will again be severe competition: the most favoured or improved varieties will be enabled to spread: there will be much extinction of the less improved forms, and the relative proportional numbers of the various inhabitants of the renewed continent will again be changed; and again there will be a fair field for natural selection to improve still further the inhabitants, and thus produce new species.

That natural selection will always act with extreme slowness, I fully admit. Its action depends on there being places in the polity of nature, which can be better occupied by some of the inhabitants of the country undergoing modification of some kind. The existence of such places will often depend on physical changes, which are generally very slow, and on the immigration of better adapted forms having been checked. But the action of natural selection will probably still oftener depend on some of the inhabitants becoming slowly modified; the mutual relations of many of the other inhabitants being thus disturbed. Nothing can be effected, unless favourable variations occur, and variation itself is apparently always a very slow process. The process will often be greatly retarded by free intercrossing. Many will exclaim that these several causes are amply sufficient wholly to stop the action of natural selection. I do not believe so. On the other hand, I do believe that natural selection will always act very slowly, often only at long intervals of time, and generally on only a very few of the inhabitants of the same region at the same time. I further believe, that this very slow, intermittent action of natural selection accords perfectly well with what geology tells us of the rate and manner at which the inhabitants of this world have changed.

Slow though the process of selection may be, if feeble man can do much by his powers of artificial selection, I can see no limit to the amount of change, to the beauty and infinite complexity of the coadaptations between all organic beings, one with another and with their physical conditions of life, which may be effected in the long course of time by nature's power of selection.

Extinction

This subject will be more fully discussed in our chapter on Geology; but it must be here alluded to from being intimately connected with natural selection. Natural selection acts solely through the preservation of variations in some way advantageous, which consequently endure. But as from the high geometrical powers of increase of all organic beings, each area is already fully stocked with inhabitants, it follows that as each selected and favoured form increases in number, so will the less favoured forms decrease and become rare. Rarity, as geology tells us, is the precursor to extinction. We can, also, see that any form represented by few individuals will, during fluctuations in the seasons or in the number of its enemies, run a good chance of utter extinction. But we may go further than this; for as new forms are continually and slowly being produced, unless we believe that the number of specific forms goes on perpetually and almost indefinitely increasing, numbers inevitably must become extinct. That the number of specific forms has not indefinitely increased, geology shows us plainly; and indeed we can see reason why they should not have thus increased, for the number of places in the polity of nature is not indefinitely great, not that we have any means of knowing that any one region has as yet got its maximum of species. probably no region is as yet fully stocked, for at the Cape of Good Hope, where more species of plants are crowded together than in any other quarter of the world, some foreign plants have become naturalised, without causing, as far as we know, the extinction of any natives.

Furthermore, the species which are most numerous in individuals will have the best chance of producing within any given period favourable variations. We have evidence of this, in the facts given in the second chapter, showing that it is the common species which afford the greatest number of recorded varieties, or incipient species. Hence, rare species will be less quickly modified or improved within any given period, and they will consequently be beaten in the race for life by the modified descendants of the commoner species.

From these several considerations I think it inevitably follows, that as new species in the course of time are formed through natural selection, others will become rarer and rarer, and finally extinct. The forms which stand in closest competition with those undergoing modification and improvement, will naturally suffer most. And we have seen in the chapter on the Struggle for Existence that it is the most closely-allied forms, varieties of the same species, and species of the same genus or of related genera, which, from having nearly the same structure, constitution, and habits, generally come into the severest competition with each other. Consequently, each new variety or species, during the progress of its formation, will generally press hardest on its nearest kindred, and tend to exterminate them. We see the same process of extermination amongst our domesticated productions, through the selection of improved forms by man. Many curious instances could be given showing how quickly new breeds of cattle, sheep, and other animals, and varieties of flowers, take the place of older and inferior kinds. In Yorkshire, it is historically known that the ancient black cattle were displaced by the long-horns, and that these 'were swept away by the short-horns' (I quote the words of an agricultural writer) 'as if by some murderous pestilence.'

Divergence of Character

The principle, which I have designated by this term, is of high importance on my theory, and explains, as I believe, several important facts. In the first place, varieties, even strongly-marked ones, though having somewhat of the character of species as is shown by the hopeless doubts in many cases how to rank them yet certainly differ from each other far less than do good and distinct species. Nevertheless, according to my view, varieties are species in the process of formation, or are, as I have called them, incipient species. How, then, does the lesser difference between varieties become augmented into the greater difference between species? That this does habitually happen, we must infer from most of the innumerable species throughout nature presenting well-marked differences; whereas varieties, the supposed prototypes and parents of future well-marked species, present slight and ill-defined differences. Mere chance, as we may call it, might cause one variety to differ in some character from its parents, and the offspring of this variety again to differ from its parent in the very same character and in a greater degree; but this alone would never account for so habitual and large an amount of difference as that between varieties of the same species and species of the same genus.

As has always been my practice, let us seek light on this head from our domestic productions. We shall here find something analogous. A fancier is struck by a pigeon having a slightly shorter beak; another fancier is struck by a pigeon having a rather longer beak; and on the acknowledged principle that 'fanciers do not and will not admire a medium standard, but like extremes,' they both go on (as has actually occurred with tumbler-pigeons) choosing and breeding from birds with longer and longer beaks, or with shorter and shorter beaks. Again, we may suppose that at an early period one man preferred swifter horses; another stronger and more bulky horses. The early differences would be very slight; in the course of time, from the continued selection of swifter horses by some breeders, and of stronger ones by others, the differences would become greater, and would be noted as forming two sub-breeds; finally, after the lapse of centuries, the sub-breeds would become converted into two well-established and distinct breeds. As the differences slowly become greater, the inferior animals with intermediate characters, being neither very swift nor very strong, will have been neglected, and will have tended to disappear. Here, then, we see in man's productions the action of what may be called the principle of divergence, causing differences, at first barely appreciable, steadily to increase, and the breeds to diverge in character both from each other and from their common parent.

But how, it may be asked, can any analogous principle apply in nature? I believe it can and does apply most efficiently, from the simple circumstance that the more diversified the descendants from any one species become in structure, constitution, and habits, by so much will they be better enabled to seize on many and widely diversified places in the polity of nature, and so be enabled to increase in numbers.

We can clearly see this in the case of animals with simple habits. Take the case of a carnivorous quadruped, of which the number that can be supported in any country has long ago arrived at its full average. If its natural powers of increase be allowed to act, it can succeed in increasing (the country not undergoing any change in its conditions) only by its varying descendants seizing on places at present occupied by other animals: some of them, for instance, being enabled to feed on new kinds of prey, either dead or alive; some inhabiting new stations, climbing trees, frequenting water, and some perhaps becoming less carnivorous. The more diversified in habits and structure the descendants of our carnivorous animal became, the more places they would be enabled to occupy. What applies to one animal will apply throughout all time to all animals that is, if they vary for otherwise natural selection can do nothing. So it will be with plants. It has been experimentally proved, that if a plot of ground be sown with several distinct genera of grasses, a greater number of plants and a greater weight of dry herbage can thus be raised. The same has been found to hold good when first one variety and then several mixed varieties of wheat have been sown on equal spaces of ground. Hence, if any one species of grass were to go on varying, and those varieties were continually selected which differed from each other in at all the same manner as distinct species and genera of grasses differ from each other, a greater number of individual plants of this species of grass, including its modified descendants, would succeed in living on the same piece of ground. And we well know that each species and each variety of grass is annually sowing almost countless seeds; and thus, as it may be said, is striving its utmost to increase its numbers. Consequently, I cannot doubt that in the course of many thousands of generations, the most distinct varieties of any one species of grass would always have the best chance of succeeding and of increasing in numbers, and thus of supplanting the less distinct varieties; and varieties, when rendered very distinct from each other, take the rank of species.

The truth of the principle, that the greatest amount of life can be supported by great diversification of structure, is seen under many natural circumstances. In an extremely small area, especially if freely open to immigration, and where the contest between individual and individual must be severe, we always find great diversity in its inhabitants. For instance, I found that a piece of turf, three feet by four in size, which had been exposed for many years to exactly the same conditions, supported twenty species of plants, and these belonged to eighteen genera and to eight orders, which shows how much these plants differed from each other. So it is with the plants and insects on small and uniform islets; and so in small ponds of fresh water. Farmers find that they can raise most food by a rotation of plants belonging to the most different orders: nature follows what may be called a simultaneous rotation. Most of the animals and plants which live close round any small piece of ground, could live on it (supposing it not to be in any way peculiar in its nature), and may be said to be striving to the utmost to live there; but, it is seen, that where they come into the closest competition with each other, the advantages of diversification of structure, with the accompanying differences of habit and constitution, determine that the inhabitants, which thus jostle each other most closely, shall, as a general rule, belong to what we call different genera and orders.

The same principle is seen in the naturalisation of plants through man's agency in foreign lands. It might have been expected that the plants which have succeeded in becoming naturalised in any land would generally have been closely allied to the indigenes; for these are commonly looked at as specially created and adapted for their own country. It might, also, perhaps have been expected that naturalised plants would have belonged to a few groups more especially adapted to certain stations in their new homes. But the case is very different; and Alph. De Candolle has well remarked in his great and admirable work, that floras gain by naturalisation, proportionally with the number of the native genera and species, far more in new genera than in new species. To give a single instance: in the last edition of Dr Asa Gray's 'Manual of the Flora of the Northern United States,' 260 naturalised plants are enumerated, and these belong to 162 genera. We thus see that these naturalised plants are of a highly diversified nature. They differ, moreover, to a large extent from the indigenes, for out of the 162 genera, no less than 100 genera are not there indigenous, and thus a large proportional addition is made to the genera of these States.

By considering the nature of the plants or animals which have struggled successfully with the indigenes of any country, and have there become naturalised, we can gain some crude idea in what manner some of the natives would have had to be modified, in order to have gained an advantage over the other natives; and we may, I think, at least safely infer that diversification of structure, amounting to new generic differences, would have been profitable to them.

The advantage of diversification in the inhabitants of the same region is, in fact, the same as that of the physiological division of labour in the organs of the same individual body a subject so well elucidated by Milne Edwards. No physiologist doubts that a stomach by being adapted to digest vegetable matter alone, or flesh alone, draws most nutriment from these substances. So in the general economy of any land, the more widely and perfectly the animals and plants are diversified for different habits of life, so will a greater number of individuals be capable of there supporting themselves. A set of animals, with their organisation but little diversified, could hardly compete with a set more perfectly diversified in structure. It may be doubted, for instance, whether the Australian marsupials, which are divided into groups differing but little from each other, and feebly representing, as Mr Waterhouse and others have remarked, our carnivorous, ruminant, and rodent mammals, could successfully compete with these well-pronounced orders. In the Australian mammals, we see the process of diversification in an early and incomplete stage of development.

After the foregoing discussion, which ought to have been much amplified, we may, I think, assume that the modified descendants of any one species will succeed by so much the better as they become more diversified in structure, and are thus enabled to encroach on places occupied by other beings. Now let us see how this principle of great benefit being derived from divergence of character, combined with the principles of natural selection and of extinction, will tend to act.

The accompanying diagram will aid us in understanding this rather perplexing subject. Let A to L represent the species of a genus large in its own country; these species are supposed to resemble each other in unequal degrees, as is so generally the case in nature, and as is represented in the diagram by the letters standing at unequal distances. I have said a large genus, because we have seen in the second chapter, that on an average more of the species of large genera vary than of small genera; and the varying species of the large genera present a greater number of varieties. We have, also, seen that the species, which are the commonest and the most widely-diffused, vary more than rare species with restricted ranges. Let (A) be a common, widely-diffused, and varying species, belonging to a genus large in its own country. The little fan of diverging dotted lines of unequal lengths proceeding from (A), may represent its varying offspring. The variations are supposed to be extremely slight, but of the most diversified nature; they are not supposed all to appear simultaneously, but often after long intervals of time; nor are they all supposed to endure for equal periods. Only those variations which are in some way profitable will be preserved or naturally selected. And here the importance of the principle of benefit being derived from divergence of character comes in; for this will generally lead to the most different or divergent variations (represented by the outer dotted lines) being preserved and accumulated by natural selection. When a dotted line reaches one of the horizontal lines, and is there marked by a small numbered letter, a sufficient amount of variation is supposed to have been accumulated to have formed a fairly well-marked variety, such as would be thought worthy of record in a systematic work.

The intervals between the horizontal lines in the diagram, may represent each a thousand generations; but it would have been better if each had represented ten thousand generations. After a thousand generations, species (A) is supposed to have produced two fairly well-marked varieties, namely a1 and m1. These two varieties will generally continue to be exposed to the same conditions which made their parents variable, and the tendency to variability is in itself hereditary, consequently they will tend to vary, and generally to vary in nearly the same manner as their parents varied. Moreover, these two varieties, being only slightly modified forms, will tend to inherit those advantages which made their common parent (A) more numerous than most of the other inhabitants of the same country; they will likewise partake of those more general advantages which made the genus to which the parent-species belonged, a large genus in its own country. And these circumstances we know to be favourable to the production of new varieties.

If, then, these two varieties be variable, the most divergent of their variations will generally be preserved during the next thousand generations. And after this interval, variety a1 is supposed in the diagram to have produced variety a2, which will, owing to the principle of divergence, differ more from (A) than did variety a1. Variety m1 is supposed to have produced two varieties, namely m 2 and s2, differing from each other, and more considerably from their common parent (A). We may continue the process by similar steps for any length of time; some of the varieties, after each thousand generations, producing only a single variety, but in a more and more modified condition, some producing two or three varieties, and some failing to produce any. Thus the varieties or modified descendants, proceeding from the common parent (A), will generally go on increasing in number and diverging in character. In the diagram the process is represented up to the ten-thousandth generation, and under a condensed and simplified form up to the fourteen-thousandth generation.

But I must here remark that I do not suppose that the process ever goes on so regularly as is represented in the diagram, though in itself made somewhat irregular. I am far from thinking that the most divergent varieties will invariably prevail and multiply: a medium form may often long endure, and may or may not produce more than one modified descendant; for natural selection will always act according to the nature of the places which are either unoccupied or not perfectly occupied by other beings; and this will depend on infinitely complex relations. But as a general rule, the more diversified in structure the descendants from any one species can be rendered, the more places they will be enabled to seize on, and the more their modified progeny will be increased. In our diagram the line of succession is broken at regular intervals by small numbered letters marking the successive forms which have become sufficiently distinct to be recorded as varieties. But these breaks are imaginary, and might have been inserted anywhere, after intervals long enough to have allowed the accumulation of a considerable amount of divergent variation.

As all the modified descendants from a common and widely-diffused species, belonging to a large genus, will tend to partake of the same advantages which made their parent successful in life, they will generally go on multiplying in number as well as diverging in character: this is represented in the diagram by the several divergent branches proceeding from (A). The modified offspring from the later and more highly improved branches in the lines of descent, will, it is probable, often take the place of, and so destroy, the earlier and less improved branches: this is represented in the diagram by some of the lower branches not reaching to the upper horizontal lines. In some cases I do not doubt that the process of modification will be confined to a single line of descent, and the number of the descendants will not be increased; although the amount of divergent modification may have been increased in the successive generations. This case would be represented in the diagram, if all the lines proceeding from (A) were removed, excepting that from a1 to a10 In the same way, for instance, the English race-horse and English pointer have apparently both gone on slowly diverging in character from their original stocks, without either having given off any fresh branches or races.

After ten thousand generations, species (A) is supposed to have produced three forms, a10, f10, and m10, which, from having diverged in character during the successive generations, will have come to differ largely, but perhaps unequally, from each other and from their common parent. If we suppose the amount of change between each horizontal line in our diagram to be excessively small, these three forms may still be only well-marked varieties; or they may have arrived at the doubtful category of sub-species; but we have only to suppose the steps in the process of modification to be more numerous or greater in amount, to convert these three forms into well-defined species: thus the diagram illustrates the steps by which the small differences distinguishing varieties are increased into the larger differences distinguishing species. By continuing the same process for a greater number of generations (as shown in the diagram in a condensed and simplified manner), we get eight species, marked by the letters between a14 and m14, all descended from (A). Thus, as I believe, species are multiplied and genera are formed.

In a large genus it is probable that more than one species would vary. In the diagram I have assumed that a second species (I) has produced, by analogous steps, after ten thousand generations, either two well-marked varieties (w10 and z10) or two species, according to the amount of change supposed to be represented between the horizontal lines. After fourteen thousand generations, six new species, marked by the letters n14 to z14, are supposed to have been produced. In each genus, the species, which are already extremely different in character, will generally tend to produce the greatest number of modified descendants; for these will have the best chance of filling new and widely different places in the polity of nature: hence in the diagram I have chosen the extreme species (A), and the nearly extreme species (I), as those which have largely varied, and have given rise to new varieties and species. The other nine species (marked by capital letters) of our original genus, may for a long period continue transmitting unaltered descendants; and this is shown in the diagram by the dotted lines not prolonged far upwards from want of space.

But during the process of modification, represented in the diagram, another of our principles, namely that of extinction, will have played an important part. As in each fully stocked country natural selection necessarily acts by the selected form having some advantage in the struggle for life over other forms, there will be a constant tendency in the improved descendants of any one species to supplant and exterminate in each stage of descent their predecessors and their original parent. For it should be remembered that the competition will generally be most severe between those forms which are most nearly related to each other in habits, constitution, and structure. Hence all the intermediate forms between the earlier and later states, that is between the less and more improved state of a species, as well as the original parent-species itself, will generally tend to become extinct. So it probably will be with many whole collateral lines of descent, which will be conquered by later and improved lines of descent. If, however, the modified offspring of a species get into some distinct country, or become quickly adapted to some quite new station, in which child and parent do not come into competition, both may continue to exist.

If then our diagram be assumed to represent a considerable amount of modification, species (A) and all the earlier varieties will have become extinct, having been replaced by eight new species (a14 to m14); and (I) will have been replaced by six (n14 to z14) new species.

But we may go further than this. The original species of our genus were supposed to resemble each other in unequal degrees, as is so generally the case in nature; species (A) being more nearly related to B, C, and D, than to the other species; and species (I) more to G, H, K, L, than to the others. These two species (A) and (I), were also supposed to be very common and widely diffused species, so that they must originally have had some advantage over most of the other species of the genus. Their modified descendants, fourteen in number at the fourteen-thousandth generation, will probably have inherited some of the same advantages: they have also been modified and improved in a diversified manner at each stage of descent, so as to have become adapted to many related places in the natural economy of their country. It seems, therefore, to me extremely probable that they will have taken the places of, and thus exterminated, not only their parents (A) and (I), but likewise some of the original species which were most nearly related to their parents. Hence very few of the original species will have transmitted offspring to the fourteen-thousandth generation. We may suppose that only one (F), of the two species which were least closely related to the other nine original species, has transmitted descendants to this late stage of descent.

The new species in our diagram descended from the original eleven species, will now be fifteen in number. Owing to the divergent tendency of natural selection, the extreme amount of difference in character between species a14 and z14 will be much greater than that between the most different of the original eleven species. The new species, moreover, will be allied to each other in a widely different manner. Of the eight descendants from (A) the three marked a14, q14, p14, will be nearly related from having recently branched off from a14; b14 and f14, from having diverged at an earlier period from a5, will be in some degree distinct from the three first-named species; and lastly, o14, e14, and m14, will be nearly related one to the other, but from having diverged at the first commencement of the process of modification, will be widely different from the other five species, and may constitute a sub-genus or even a distinct genus. The six descendants from (I) will form two sub-genera or even genera. But as the original species (I) differed largely from (A), standing nearly at the extreme points of the original genus, the six descendants from (I) will, owing to inheritance, differ considerably from the eight descendants from (A); the two groups, moreover, are supposed to have gone on diverging in different directions. The intermediate species, also (and this is a very important consideration), which connected the original species (A) and (I), have all become, excepting (F), extinct, and have left no descendants. Hence the six new species descended from (I), and the eight descended from (A), will have to be ranked as very distinct genera, or even as distinct sub-families.

Thus it is, as I believe, that two or more genera are produced by descent, with modification, from two or more species of the same genus. And the two or more parent-species are supposed to have descended from some one species of an earlier genus. In our diagram, this is indicated by the broken lines, beneath the capital letters, converging in sub-branches downwards towards a single point; this point representing a single species, the supposed single parent of our several new sub-genera and genera.

It is worth while to reflect for a moment on the character of the new species F14, which is supposed not to have diverged much in character, but to have retained the form of (F), either unaltered or altered only in a slight degree. In this case, its affinities to the other fourteen new species will be of a curious and circuitous nature. Having descended from a form which stood between the two parent-species (A) and (I), now supposed to be extinct and unknown, it will be in some degree intermediate in character between the two groups descended from these species. But as these two groups have gone on diverging in character from the type of their parents, the new species (F14) will not be directly intermediate between them, but rather between types of the two groups; and every naturalist will be able to bring some such case before his mind.

In the diagram, each horizontal line has hitherto been supposed to represent a thousand generations, but each may represent a million or hundred million generations, and likewise a section of the successive strata of the earth's crust including extinct remains. We shall, when we come to our chapter on Geology, have to refer again to this subject, and I think we shall then see that the diagram throws light on the affinities of extinct beings, which, though generally belonging to the same orders, or families, or genera, with those now living, yet are often, in some degree, intermediate in character between existing groups; and we can understand this fact, for the extinct species lived at very ancient epochs when the branching lines of descent had diverged less.

I see no reason to limit the process of modification, as now explained, to the formation of genera alone. If, in our diagram, we suppose the amount of change represented by each successive group of diverging dotted lines to be very great, the forms marked a214 to p14, those marked b14 and f14, and those marked o14 to m14, will form three very distinct genera. We shall also have two very distinct genera descended from (I) and as these latter two genera, both from continued divergence of character and from inheritance from a different parent, will differ widely from the three genera descended from (A), the two little groups of genera will form two distinct families, or even orders, according to the amount of divergent modification supposed to be represented in the diagram. And the two new families, or orders, will have descended from two species of the original genus; and these two species are supposed to have descended from one species of a still more ancient and unknown genus.

We have seen that in each country it is the species of the larger genera which oftenest present varieties or incipient species. This, indeed, might have been expected; for as natural selection acts through one form having some advantage over other forms in the struggle for existence, it will chiefly act on those which already have some advantage; and the largeness of any group shows that its species have inherited from a common ancestor some advantage in common. Hence, the struggle for the production of new and modified descendants, will mainly lie between the larger groups, which are all trying to increase in number. One large group will slowly conquer another large group, reduce its numbers, and thus lessen its chance of further variation and improvement. Within the same large group, the later and more highly perfected sub-groups, from branching out and seizing on many new places in the polity of Nature, will constantly tend to supplant and destroy the earlier and less improved sub-groups. Small and broken groups and sub-groups will finally tend to disappear. Looking to the future, we can predict that the groups of organic beings which are now large and triumphant, and which are least broken up, that is, which as yet have suffered least extinction, will for a long period continue to increase. But which groups will ultimately prevail, no man can predict; for we well know that many groups, formerly most extensively developed, have now become extinct. Looking still more remotely to the future, we may predict that, owing to the continued and steady increase of the larger groups, a multitude of smaller groups will become utterly extinct, and leave no modified descendants; and consequently that of the species living at any one period, extremely few will transmit descendants to a remote futurity. I shall have to return to this subject in the chapter on Classification, but I may add that on this view of extremely few of the more ancient species having transmitted descendants, and on the view of all the descendants of the same species making a class, we can understand how it is that there exist but very few classes in each main division of the animal and vegetable kingdoms. Although extremely few of the most ancient species may now have living and modified descendants, yet at the most remote geological period, the earth may have been as well peopled with many species of many genera, families, orders, and classes, as at the present day.

Summary of Chapter

If during the long course of ages and under varying conditions of life, organic beings vary at all in the several parts of their organisation, and I think this cannot be disputed; if there be, owing to the high geometrical powers of increase of each species, at some age, season, or year, a severe struggle for life, and this certainly cannot be disputed; then, considering the infinite complexity of the relations of all organic beings to each other and to their conditions of existence, causing an infinite diversity in structure, constitution, and habits, to be advantageous to them, I think it would be a most extraordinary fact if no variation ever had occurred useful to each being's own welfare, in the same way as so many variations have occurred useful to man. But if variations useful to any organic being do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterised. This principle of preservation, I have called, for the sake of brevity, Natural Selection. Natural selection, on the principle of qualities being inherited at corresponding ages, can modify the egg, seed, or young, as easily as the adult. Amongst many animals, sexual selection will give its aid to ordinary selection, by assuring to the most vigorous and best adapted males the greatest number of offspring. Sexual selection will also give characters useful to the males alone, in their struggles with other males.

Whether natural selection has really thus acted in nature, in modifying and adapting the various forms of life to their several conditions and stations, must be judged of by the general tenour and balance of evidence given in the following chapters. But we already see how it entails extinction; and how largely extinction has acted in the world's history, geology plainly declares. Natural selection, also, leads to divergence of character; for more living beings can be supported on the same area the more they diverge in structure, habits, and constitution, of which we see proof by looking at the inhabitants of any small spot or at naturalised productions. Therefore during the modification of the descendants of any one species, and during the incessant struggle of all species to increase in numbers, the more diversified these descendants become, the better will be their chance of succeeding in the battle of life. Thus the small differences distinguishing varieties of the same species, will steadily tend to increase till they come to equal the greater differences between species of the same genus, or even of distinct genera.

We have seen that it is the common, the widely-diffused, and widely-ranging species, belonging to the larger genera, which vary most; and these will tend to transmit to their modified offspring that superiority which now makes them dominant in their own countries. Natural selection, as has just been remarked, leads to divergence of character and to much extinction of the less improved and intermediate forms of life. On these principles, I believe, the nature of the affinities of all organic beings may be explained. It is a truly wonderful fact the wonder of which we are apt to overlook from familiarity that all animals and all plants throughout all time and space should be related to each other in group subordinate to group, in the manner which we everywhere behold namely, varieties of the same species most closely related together, species of the same genus less closely and unequally related together, forming sections and sub-genera, species of distinct genera much less closely related, and genera related in different degrees, forming sub-families, families, orders, sub-classes, and classes. The several subordinate groups in any class cannot be ranked in a single file, but seem rather to be clustered round points, and these round other points, and so on in almost endless cycles. On the view that each species has been independently created, I can see no explanation of this great fact in the classification of all organic beings; but, to the best of my judgment, it is explained through inheritance and the complex action of natural selection, entailing extinction and divergence of character, as we have seen illustrated in the diagram.

The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth. The green and budding twigs may represent existing species; and those produced during each former year may represent the long succession of extinct species. At each period of growth all the growing twigs have tried to branch out on all sides, and to overtop and kill the surrounding twigs and branches, in the same manner as species and groups of species have tried to overmaster other species in the great battle for life. The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was small, budding twigs; and this connexion of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear all the other branches; so with the species which lived during long-past geological periods, very few now have living and modified descendants. From the first growth of the tree, many a limb and branch has decayed and dropped off; and these lost branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only from having been found in a fossil state. As we here and there see a thin straggling branch springing from a fork low down in a tree, and which by some chance has been favoured and is still alive on its summit, so we occasionally see an animal like the Ornithorhynchus or Lepidosiren, which in some small degree connects by its affinities two large branches of life, and which has apparently been saved from fatal competition by having inhabited a protected station. As buds give rise by growth to fresh buds, and these, if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications. 
HAVE hitherto sometimes spoken as if the variations so common and multiform in organic beings under domestication, and in a lesser degree in those in a state of nature had been due to chance. This, of course, is a wholly incorrect expression, but it serves to acknowledge plainly our ignorance of the cause of each particular variation. Some authors believe it to be as much the function of the reproductive system to produce individual differences, or very slight deviations of structure, as to make the child like its parents. But the much greater variability, as well as the greater frequency of monstrosities, under domestication or cultivation, than under nature, leads me to believe that deviations of structure are in some way due to the nature of the conditions of life, to which the parents and their more remote ancestors have been exposed during several generations. I have remarked in the first chapter but a long catalogue of facts which cannot be here given would be necessary to show the truth of the remark that the reproductive system is eminently susceptible to changes in the conditions of life; and to this system being functionally disturbed in the parents, I chiefly attribute the varying or plastic condition of the offspring. The male and female sexual elements seem to be affected before that union takes place which is to form a new being. In the case of 'sporting' plants, the bud, which in its earliest condition does not apparently differ essentially from an ovule, is alone affected. But why, because the reproductive system is disturbed, this or that part should vary more or less, we are profoundly ignorant. Nevertheless, we can here and there dimly catch a faint ray of light, and we may feel sure that there must be some cause for each deviation of structure, however slight.

How much direct effect difference of climate, food, &c., produces on any being is extremely doubtful. My impression is, that the effect is extremely small in the case of animals, but perhaps rather more in that of plants. We may, at least, safely conclude that such influences cannot have produced the many striking and complex co-adaptations of structure between one organic being and another, which we see everywhere throughout nature. Some little influence may be attributed to climate, food, &c.: thus, E. Forbes speaks confidently that shells at their southern limit, and when living in shallow water, are more brightly coloured than those of the same species further north or from greater depths. Gould believes that birds of the same species are more brightly coloured under a clear atmosphere, than when living on islands or near the coast. So with insects, Wollaston is convinced that residence near the sea affects their colours. Moquin-Tandon gives a list of plants which when growing near the sea-shore have their leaves in some degree fleshy, though not elsewhere fleshy. Several other such cases could be given.

The fact of varieties of one species, when they range into the zone of habitation of other species, often acquiring in a very slight degree some of the characters of such species, accords with our view that species of all kinds are only well-marked and permanent varieties. Thus the species of shells which are confined to tropical and shallow seas are generally brighter-coloured than those confined to cold and deeper seas. The birds which are confined to continents are, according to Mr Gould, brighter-coloured than those of islands. The insect-species confined to sea-coasts, as every collector knows, are often brassy or lurid. Plants which live exclusively on the sea-side are very apt to have fleshy leaves. He who believes in the creation of each species, will have to say that this shell, for instance, was created with bright colours for a warm sea; but that this other shell became bright-coloured by variation when it ranged into warmer or shallower waters.

When a variation is of the slightest use to a being, we cannot tell how much of it to attribute to the accumulative action of natural selection, and how much to the conditions of life. Thus, it is well known to furriers that animals of the same species have thicker and better fur the more severe the climate is under which they have lived; but who can tell how much of this difference may be due to the warmest-clad individuals having been favoured and preserved during many generations, and how much to the direct action of the severe climate? for it would appear that climate has some direct action on the hair of our domestic quadrupeds.

Instances could be given of the same variety being produced under conditions of life as different as can well be conceived; and, on the other hand, of different varieties being produced from the same species under the same conditions. Such facts show how indirectly the conditions of life must act. Again, innumerable instances are known to every naturalist of species keeping true, or not varying at all, although living under the most opposite climates. Such considerations as these incline me to lay very little weight on the direct action of the conditions of life. Indirectly, as already remarked, they seem to play an important part in affecting the reproductive system, and in thus inducing variability; and natural selection will then accumulate all profitable variations, however slight, until they become plainly developed and appreciable by us.

Effects of Use and Disuse

From the facts alluded to in the first chapter, I think there can be little doubt that use in our domestic animals strengthens and enlarges certain parts, and disuse diminishes them; and that such modifications are inherited. Under free nature, we can have no standard of comparison, by which to judge of the effects of long-continued use or disuse, for we know not the parent-forms; but many animals have structures which can be explained by the effects of disuse. As Professor Owen has remarked, there is no greater anomaly in nature than a bird that cannot fly; yet there are several in this state. The logger-headed duck of South America can only flap along the surface of the water, and has its wings in nearly the same condition as the domestic Aylesbury duck. As the larger ground-feeding birds seldom take flight except to escape danger, I believe that the nearly wingless condition of several birds, which now inhabit or have lately inhabited several oceanic islands, tenanted by no beast of prey, has been caused by disuse. The ostrich indeed inhabits continents and is exposed to danger from which it cannot escape by flight, but by kicking it can defend itself from enemies, as well as any of the smaller quadrupeds. We may imagine that the early progenitor of the ostrich had habits like those of a bustard, and that as natural selection increased in successive generations the size and weight of its body, its legs were used more, and its wings less, until they became incapable of flight.

Kirby has remarked (and I have observed the same fact) that the anterior tarsi, or feet, of many male dung-feeding beetles are very often broken off; he examined seventeen specimens in his own collection, and not one had even a relic left. In the Onites apelles the tarsi are so habitually lost, that the insect has been described as not having them. In some other genera they are present, but in a rudimentary condition. In the Ateuchus or sacred beetle of the Egyptians, they are totally deficient. There is not sufficient evidence to induce us to believe that mutilations are ever inherited; and I should prefer explaining the entire absence of the anterior tarsi in Ateuchus, and their rudimentary condition in some other genera, by the long-continued effects of disuse in their progenitors; for as the tarsi are almost always lost in many dung-feeding beetles, they must be lost early in life, and therefore cannot be much used by these insects.

In some cases we might easily put down to disuse modifications of structure which are wholly, or mainly, due to natural selection. Mr. Wollaston has discovered the remarkable fact that 200 beetles, out of the 550 species inhabiting Madeira, are so far deficient in wings that they cannot fly; and that of the twenty-nine endemic genera, no less than twenty-three genera have all their species in this condition! Several facts, namely, that beetles in many parts of the world are very frequently blown to sea and perish; that the beetles in Madeira, as observed by Mr Wollaston, lie much concealed, until the wind lulls and the sun shines; that the proportion of wingless beetles is larger on the exposed Dezertas than in Madeira itself; and especially the extraordinary fact, so strongly insisted on by Mr. Wollaston, of the almost entire absence of certain large groups of beetles, elsewhere excessively numerous, and which groups have habits of life almost necessitating frequent flight; these several considerations have made me believe that the wingless condition of so many Madeira beetles is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of successive generations each individual beetle which flew least, either from its wings having been ever so little less perfectly developed or from indolent habit, will have had the best chance of surviving from not being blown out to sea; and, on the other hand, those beetles which most readily took to flight will oftenest have been blown to sea and thus have been destroyed.

The insects in Madeira which are not ground-feeders, and which, as the flower-feeding coleoptera and lepidoptera, must habitually use their wings to gain their subsistence, have, as Mr. Wollaston suspects, their wings not at all reduced, but even enlarged. This is quite compatible with the action of natural selection. For when a new insect first arrived on the island, the tendency of natural selection to enlarge or to reduce the wings, would depend on whether a greater number of individuals were saved by successfully battling with the winds, or by giving up the attempt and rarely or never flying. As with mariners ship-wrecked near a coast, it would have been better for the good swimmers if they had been able to swim still further, whereas it would have been better for the bad swimmers if they had not been able to swim at all and had stuck to the wreck.

The eyes of moles and of some burrowing rodents are rudimentary in size, and in some cases are quite covered up by skin and fur. This state of the eyes is probably due to gradual reduction from disuse, but aided perhaps by natural selection. In South America, a burrowing rodent, the tuco-tuco, or Ctenomys, is even more subterranean in its habits than the mole; and I was assured by a Spaniard, who had often caught them, that they were frequently blind; one which I kept alive was certainly in this condition, the cause, as appeared on dissection, having been inflammation of the nictitating membrane. As frequent inflammation of the eyes must be injurious to any animal, and as eyes are certainly not indispensable to animals with subterranean habits, a reduction in their size with the adhesion of the eyelids and growth of fur over them, might in such case be an advantage; and if so, natural selection would constantly aid the effects of disuse.

It is well known that several animals, belonging to the most different classes, which inhabit the caves of Styria and of Kentucky, are blind. In some of the crabs the foot-stalk for the eye remains, though the eye is gone; the stand for the telescope is there, though the telescope with its glasses has been lost. As it is difficult to imagine that eyes, though useless, could be in any way injurious to animals living in darkness, I attribute their loss wholly to disuse. In one of the blind animals, namely, the cave-rat, the eyes are of immense size; and Professor Silliman thought that it regained, after living some days in the light, some slight power of vision. In the same manner as in Madeira the wings of some of the insects have been enlarged, and the wings of others have been reduced by natural selection aided by use and disuse, so in the case of the cave-rat natural selection seems to have struggled with the loss of light and to have increased the size of the eyes; whereas with all the other inhabitants of the caves, disuse by itself seems to have done its work.

It is difficult to imagine conditions of life more similar than deep limestone caverns under a nearly similar climate; so that on the common view of the blind animals having been separately created for the American and European caverns, close similarity in their organisation and affinities might have been expected; but, as Schiödte and others have remarked, this is not the case, and the cave-insects of the two continents are not more closely allied than might have been anticipated from the general resemblance of the other inhabitants of North America and Europe. On my view we must suppose that American animals, having ordinary powers of vision, slowly migrated by successive generations from the outer world into the deeper and deeper recesses of the Kentucky caves, as did European animals into the caves of Europe. We have some evidence of this gradation of habit; for, as Schiödte remarks, 'animals not far remote from ordinary forms, prepare the transition from light to darkness. Next follow those that are constructed for twilight; and, last of all, those destined for total darkness.' By the time that an animal had reached, after numberless generations, the deepest recesses, disuse will on this view have more or less perfectly obliterated its eyes, and natural selection will often have effected other changes, such as an increase in the length of the antennae or palpi, as a compensation for blindness. Notwithstanding such modifications, we might expect still to see in the cave-animals of America, affinities to the other inhabitants of that continent, and in those of Europe, to the inhabitants of the European continent. And this is the case with some of the American cave-animals, as I hear from Professor Dana; and some of the European cave-insects are very closely allied to those of the surrounding country. It would be most difficult to give any rational explanation of the affinities of the blind cave-animals to the other inhabitants of the two continents on the ordinary view of their independent creation. That several of the inhabitants of the caves of the Old and New Worlds should be closely related, we might expect from the well-known relationship of most of their other productions. Far from feeling any surprise that some of the cave-animals should be very anomalous, as Agassiz has remarked in regard to the blind fish, the Amblyopsis, and as is the case with the blind Proteus with reference to the reptiles of Europe, I am only surprised that more wrecks of ancient life have not been preserved, owing to the less severe competition to which the inhabitants of these dark abodes will probably have been exposed.

Acclimatisation

Habit is hereditary with plants, as in the period of flowering, in the amount of rain requisite for seeds to germinate, in the time of sleep, &c., and this leads me to say a few words on acclimatisation. As it is extremely common for species of the same genus to inhabit very hot and very cold countries, and as I believe that all the species of the same genus have descended from a single parent, if this view be correct, acclimatisation must be readily effected during long-continued descent. It is notorious that each species is adapted to the climate of its own home: species from an arctic or even from a temperate region cannot endure a tropical climate, or conversely. So again, many succulent plants cannot endure a damp climate. But the degree of adaptation of species to the climates under which they live is often overrated. We may infer this from our frequent inability to predict whether or not an imported plant will endure our climate, and from the number of plants and animals brought from warmer countries which here enjoy good health. We have reason to believe that species in a state of nature are limited in their ranges by the competition of other organic beings quite as much as, or more than, by adaptation to particular climates. But whether or not the adaptation be generally very close, we have evidence, in the case of some few plants, of their becoming, to a certain extent, naturally habituated to different temperatures, or becoming acclimatised: thus the pines and rhododendrons, raised from seed collected by Dr Hooker from trees growing at different heights on the Himalaya were found in this country to possess different constitutional powers of resisting cold. Mr Thwaites informs me that he has observed similar facts in Ceylon, and analogous observations have been made by Mr H. C. Watson on European species of plants brought from the Azores to England. In regard to animals, several authentic cases could be given of species within historical times having largely extended their range from warmer to cooler latitudes, and conversely; but we do not positively know that these animals were strictly adapted to their native climate, but in all ordinary cases we assume such to be the case; nor do we know that they have subsequently become acclimatised to their new homes.

As I believe that our domestic animals were originally chosen by uncivilised man because they were useful and bred readily under confinement, and not because they were subsequently found capable of far-extended transportation, I think the common and extraordinary capacity in our domestic animals of not only withstanding the most different climates but of being perfectly fertile (a far severer test) under them, may be used as an argument that a large proportion of other animals, now in a state of nature, could easily be brought to bear widely different climates. We must not, however, push the foregoing argument too far, on account of the probable origin of some of our domestic animals from several wild stocks: the blood, for instance, of a tropical and arctic wolf or wild dog may perhaps be mingled in our domestic breeds. The rat and mouse cannot be considered as domestic animals, but they have been transported by man to many parts of the world, and now have a far wider range than any other rodent, living free under the cold climate of Faroe in the north and of the Falklands in the south, and on many islands in the torrid zones. Hence I am inclined to look at adaptation to any special climate as a quality readily grafted on an innate wide flexibility of constitution, which is common to most animals. On this view, the capacity of enduring the most different climates by man himself and by his domestic animals, and such facts as that former species of the elephant and rhinoceros were capable of enduring a glacial climate, whereas the living species are now all tropical or sub-tropical in their habits, ought not to be looked at as anomalies, but merely as examples of a very common flexibility of constitution, brought, under peculiar circumstances, into play.

How much of the acclimatisation of species to any peculiar climate is due to mere habit, and how much to the natural selection of varieties having different innate constitutions, and how much to means combined, is a very obscure question. That habit or custom has some influence I must believe, both from analogy, and from the incessant advice given in agricultural works, even in the ancient Encyclopaedias of China, to be very cautious in transposing animals from one district to another; for it is not likely that man should have succeeded in selecting so many breeds and sub-breeds with constitutions specially fitted for their own districts: the result must, I think, be due to habit. On the other hand, I can see no reason to doubt that natural selection will continually tend to preserve those individuals which are born with constitutions best adapted to their native countries. In treatises on many kinds of cultivated plants, certain varieties are said to withstand certain climates better than others: this is very strikingly shown in works on fruit trees published in the United States, in which certain varieties are habitually recommended for the northern, and others for the southern States; and as most of these varieties are of recent origin, they cannot owe their constitutional differences to habit. The case of the Jerusalem artichoke, which is never propagated by seed, and of which consequently new varieties have not been produced, has even been advanced for it is now as tender as ever it was -- as proving that acclimatisation cannot be effected! The case, also, of the kidney-bean has been often cited for a similar purpose, and with much greater weight; but until some one will sow, during a score of generations, his kidney-beans so early that a very large proportion are destroyed by frost, and then collect seed from the few survivors, with care to prevent accidental crosses, and then again get seed from these seedlings, with the same precautions, the experiment cannot be said to have been even tried. Nor let it be supposed that no differences in the constitution of seedling kidney-beans ever appear, for an account has been published how much more hardy some seedlings appeared to be than others.

On the whole, I think we may conclude that habit, use, and disuse, have, in some cases, played a considerable part in the modification of the constitution, and of the structure of various organs; but that the effects of use and disuse have often been largely combined with, and sometimes overmastered by, the natural selection of innate differences.

Correlation of Growth

I mean by this expression that the whole organisation is so tied together during its growth and development, that when slight variations in any one part occur, and are accumulated through natural selection, other parts become modified. This is a very important subject, most imperfectly understood. The most obvious case is, that modifications accumulated solely for the good of the young or larva, will, it may safely be concluded, affect the structure of the adult; in the same manner as any malconformation affecting the early embryo, seriously affects the whole organisation of the adult. The several parts of the body which are homologous, and which, at an early embryonic period, are alike, seem liable to vary in an allied manner: we see this in the right and left sides of the body varying in the same manner; in the front and hind legs, and even in the jaws and limbs, varying together, for the lower jaw is believed to be homologous with the limbs. These tendencies, I do not doubt, may be mastered more or less completely by natural selection: thus a family of stags once existed with an antler only on one side; and if this had been of any great use to the breed it might probably have been rendered permanent by natural selection.

Homologous parts, as has been remarked by some authors, tend to cohere; this is often seen in monstrous plants; and nothing is more common than the union of homologous parts in normal structures, as the union of the petals of the corolla into a tube. Hard parts seem to affect the form of adjoining soft parts; it is believed by some authors that the diversity in the shape of the pelvis in birds causes the remarkable diversity in the shape of their kidneys. Others believe that the shape of the pelvis in the human mother influences by pressure the shape of the head of the child. In snakes, according to Schlegel, the shape of the body and the manner of swallowing determine the position of several of the most important viscera.

The nature of the bond of correlation is very frequently quite obscure. M. Is. Geoffroy St Hilaire has forcibly remarked, that certain malconformations very frequently, and that others rarely coexist, without our being able to assign any reason. What can be more singular than the relation between blue eyes and deafness in cats, and the tortoise-shell colour with the female sex; the feathered feet and skin between the outer toes in pigeons, and the presence of more or less down on the young birds when first hatched, with the future colour of their plumage; or, again, the relation between the hair and teeth in the naked Turkish dog, though here probably homology comes into play? With respect to this latter case of correlation, I think it can hardly be accidental, that if we pick out the two orders of mammalia which are most abnormal in their dermal coverings, viz. Cetacea (whales) and Edentata (armadilloes, scaly ant-eaters, &c.), that these are likewise the most abnormal in their teeth.

I know of no case better adapted to show the importance of the laws of correlation in modifying important structures, independently of utility and, therefore, of natural selection, than that of the difference between the outer and inner flowers in some Compositous and Umbelliferous plants. Every one knows the difference in the ray and central florets of, for instance, the daisy, and this difference is often accompanied with the abortion of parts of the flower. But, in some Compositous plants, the seeds also differ in shape and sculpture; and even the ovary itself, with its accessory parts, differs, as has been described by Cassini. These differences have been attributed by some authors to pressure, and the shape of the seeds in the ray-florets in some Compositae countenances this idea; but, in the case of the corolla of the Umbelliferae, it is by no means, as Dr Hooker informs me, in species with the densest heads that the inner and outer flowers most frequently differ. It might have been thought that the development of the ray-petals by drawing nourishment from certain other parts of the flower had caused their abortion; but in some Compositae there is a difference in the seeds of the outer and inner florets without any difference in the corolla. Possibly, these several differences may be connected with some difference in the flow of nutriment towards the central and external flowers: we know, at least, that in irregular flowers, those nearest to the axis are oftenest subject to peloria, and become regular. I may add, as an instance of this, and of a striking case of correlation, that I have recently observed in some garden pelargoniums, that the central flower of the truss often loses the patches of darker colour in the two upper petals; and that when this occurs, the adherent nectary is quite aborted; when the colour is absent from only one of the two upper petals, the nectary is only much shortened.

With respect to the difference in the corolla of the central and exterior flowers of a head or umbel, I do not feel at all sure that C. C. Sprengel's idea that the ray-florets serve to attract insects, whose agency is highly advantageous in the fertilisation of plants of these two orders, is so far-fetched, as it may at first appear: and if it be advantageous, natural selection may have come into play. But in regard to the differences both in the internal and external structure of the seeds, which are not always correlated with any differences in the flowers, it seems impossible that they can be in any way advantageous to the plant: yet in the Umbelliferae these differences are of such apparent importance the seeds being in some cases, according to Tausch, orthospermous in the exterior flowers and coelospermous in the central flowers, that the elder De Candolle founded his main divisions of the order on analogous differences. Hence we see that modifications of structure, viewed by systematists as of high value, may be wholly due to unknown laws of correlated growth, and without being, as far as we can see, of the slightest service to the species.

We may often falsely attribute to correlation of growth, structures which are common to whole groups of species, and which in truth are simply due to inheritance; for an ancient progenitor may have acquired through natural selection some one modification in structure, and, after thousands of generations, some other and independent modification; and these two modifications, having been transmitted to a whole group of descendants with diverse habits, would naturally be thought to be correlated in some necessary manner. So, again, I do not doubt that some apparent correlations, occurring throughout whole orders, are entirely due to the manner alone in which natural selection can act. For instance, Alph. De Candolle has remarked that winged seeds are never found in fruits which do not open: I should explain the rule by the fact that seeds could not gradually become winged through natural selection, except in fruits which opened; so that the individual plants producing seeds which were a little better fitted to be wafted further, might get an advantage over those producing seed less fitted for dispersal; and this process could not possibly go on in fruit which did not open.

The elder Geoffroy and Goethe propounded, at about the same period, their law of compensation or balancement of growth; or, as Goethe expressed it, 'in order to spend on one side, nature is forced to economise on the other side.' I think this holds true to a certain extent with our domestic productions: if nourishment flows to one part or organ in excess, it rarely flows, at least in excess, to another part; thus it is difficult to get a cow to give much milk and to fatten readily. The same varieties of the cabbage do not yield abundant and nutritious foliage and a copious supply of oil-bearing seeds. When the seeds in our fruits become atrophied, the fruit itself gains largely in size and quality. In our poultry, a large tuft of feathers on the head is generally accompanied by a diminished comb, and a large beard by diminished wattles. With species in a state of nature it can hardly be maintained that the law is of universal application; but many good observers, more especially botanists, believe in its truth. I will not, however, here give any instances, for I see hardly any way of distinguishing between the effects, on the one hand, of a part being largely developed through natural selection and another and adjoining part being reduced by this same process or by disuse, and, on the other hand, the actual withdrawal of nutriment from one part owing to the excess of growth in another and adjoining part.

I suspect, also, that some of the cases of compensation which have been advanced, and likewise some other facts, may be merged under a more general principle, namely, that natural selection is continually trying to economise in every part of the organisation. If under changed conditions of life a structure before useful becomes less useful, any diminution, however slight, in its development, will be seized on by natural selection, for it will profit the individual not to have its nutriment wasted in building up an useless structure. I can thus only understand a fact with which I was much struck when examining cirripedes, and of which many other instances could be given: namely, that when a cirripede is parasitic within another and is thus protected, it loses more or less completely its own shell or carapace. This is the case with the male Ibla, and in a truly extraordinary manner with the Proteolepas: for the carapace in all other cirripedes consists of the three highly-important anterior segments of the head enormously developed, and furnished with great nerves and muscles; but in the parasitic and protected Proteolepas, the whole anterior part of the head is reduced to the merest rudiment attached to the bases of the prehensile antennae. Now the saving of a large and complex structure, when rendered superfluous by the parasitic habits of the Proteolepas, though effected by slow steps, would be a decided advantage to each successive individual of the species; for in the struggle for life to which every animal is exposed, each individual Proteolepas would have a better chance of supporting itself, by less nutriment being wasted in developing a structure now become useless.

Thus, as I believe, natural selection will always succeed in the long run in reducing and saving every part of the organisation, as soon as it is rendered superfluous, without by any means causing some other part to be largely developed in a corresponding degree. And, conversely, that natural selection may perfectly well succeed in largely developing any organ, without requiring as a necessary compensation the reduction of some adjoining part.

It seems to be a rule, as remarked by Is. Geoffroy St Hilaire, both in varieties and in species, that when any part or organ is repeated many times in the structure of the same individual (as the vertebrae in snakes, and the stamens in polyandrous flowers) the number is variable; whereas the number of the same part or organ, when it occurs in lesser numbers, is constant. The same author and some botanists have further remarked that multiple parts are also very liable to variation in structure. Inasmuch as this 'vegetative repetition,' to use Prof. Owen's expression, seems to be a sign of low organisation; the foregoing remark seems connected with the very general opinion of naturalists, that beings low in the scale of nature are more variable than those which are higher. I presume that lowness in this case means that the several parts of the organisation have been but little specialised for particular functions; and as long as the same part has to perform diversified work, we can perhaps see why it should remain variable, that is, why natural selection should have preserved or rejected each little deviation of form less carefully than when the part has to serve for one special purpose alone. In the same way that a knife which has to cut all sorts of things may be of almost any shape; whilst a tool for some particular object had better be of some particular shape. Natural selection, it should never be forgotten, can act on each part of each being, solely through and for its advantage.

Rudimentary parts, it has been stated by some authors, and I believe with truth, are apt to be highly variable. We shall have to recur to the general subject of rudimentary and aborted organs; and I will here only add that their variability seems to be owing to their uselessness, and therefore to natural selection having no power to check deviations in their structure. Thus rudimentary parts are left to the free play of the various laws of growth, to the effects of long-continued disuse, and to the tendency to reversion.

A part developed in any species in an extraordinary degree or manner, in comparison with the same part in allied species, tends to be highly variable.

Several years ago I was much struck with a remark, nearly to the above effect, published by Mr Waterhouse. I infer also from an observation made by Professor Owen, with respect to the length of the arms of the ourang-outang, that he has come to a nearly similar conclusion. It is hopeless to attempt to convince any one of the truth of this proposition without giving the long array of facts which I have collected, and which cannot possibly be here introduced. I can only state my conviction that it is a rule of high generality. I am aware of several causes of error, but I hope that I have made due allowance for them. It should be understood that the rule by no means applies to any part, however unusually developed, unless it be unusually developed in comparison with the same part in closely allied species. Thus, the bat's wing is a most abnormal structure in the class mammalia; but the rule would not here apply, because there is a whole group of bats having wings; it would apply only if some one species of bat had its wings developed in some remarkable manner in comparison with the other species of the same genus. The rule applies very strongly in the case of secondary sexual characters, when displayed in any unusual manner. The term, secondary sexual characters, used by Hunter, applies to characters which are attached to one sex, but are not directly connected with the act of reproduction. The rule applies to males and females; but as females more rarely offer remarkable secondary sexual characters, it applies more rarely to them. The rule being so plainly applicable in the case of secondary sexual characters, may be due to the great variability of these characters, whether or not displayed in any unusual manner of which fact I think there can be little doubt. But that our rule is not confined to secondary sexual characters is clearly shown in the case of hermaphrodite cirripedes; and I may here add, that I particularly attended to Mr. Waterhouse's remark, whilst investigating this Order, and I am fully convinced that the rule almost invariably holds good with cirripedes. I shall, in my future work, give a list of the more remarkable cases; I will here only briefly give one, as it illustrates the rule in its largest application. The opercular valves of sessile cirripedes (rock barnacles) are, in every sense of the word, very important structures, and they differ extremely little even in different genera; but in the several species of one genus, Pyrgoma, these valves present a marvellous amount of diversification: the homologous valves in the different species being sometimes wholly unlike in shape; and the amount of variation in the individuals of several of the species is so great, that it is no exaggeration to state that the varieties differ more from each other in the characters of these important valves than do other species of distinct genera.

As birds within the same country vary in a remarkably small degree, I have particularly attended to them, and the rule seems to me certainly to hold good in this class. I cannot make out that it applies to plants, and this would seriously have shaken my belief in its truth, had not the great variability in plants made it particularly difficult to compare their relative degrees of variability.

When we see any part or organ developed in a remarkable degree or manner in any species, the fair presumption is that it is of high importance to that species; nevertheless the part in this case is eminently liable to variation. Why should this be so? On the view that each species has been independently created, with all its parts as we now see them, I can see no explanation. But on the view that groups of species have descended from other species, and have been modified through natural selection, I think we can obtain some light. In our domestic animals, if any part, or the whole animal, be neglected and no selection be applied, that part (for instance, the comb in the Dorking fowl) or the whole breed will cease to have a nearly uniform character. The breed will then be said to have degenerated. In rudimentary organs, and in those which have been but little specialized for any particular purpose, and perhaps in polymorphic groups, we see a nearly parallel natural case; for in such cases natural selection either has not or cannot come into full play, and thus the organisation is left in a fluctuating condition. But what here more especially concerns us is, that in our domestic animals those points, which at the present time are undergoing rapid change by continued selection, are also eminently liable to variation. Look at the breeds of the pigeon; see what a prodigious amount of difference there is in the beak of the different tumblers, in the beak and wattle of the different carriers, in the carriage and tail of our fantails, &c., these being the points now mainly attended to by English fanciers. Even in the sub-breeds, as in the short-faced tumbler, it is notoriously difficult to breed them nearly to perfection, and frequently individuals are born which depart widely from the standard. There may be truly said to be a constant struggle going on between, on the one hand, the tendency to reversion to a less modified state, as well as an innate tendency to further variability of all kinds, and, on the other hand, the power of steady selection to keep the breed true. In the long run selection gains the day, and we do not expect to fail so far as to breed a bird as coarse as a common tumbler from a good short-faced strain. But as long as selection is rapidly going on, there may always be expected to be much variability in the structure undergoing modification. It further deserves notice that these variable characters, produced by man's selection, sometimes become attached, from causes quite unknown to us, more to one sex than to the other, generally to the male sex, as with the wattle of carriers and the enlarged crop of pouters.

Now let us turn to nature. When a part has been developed in an extraordinary manner in any one species, compared with the other species of the same genus, we may conclude that this part has undergone an extraordinary amount of modification, since the period when the species branched off from the common progenitor of the genus. This period will seldom be remote in any extreme degree, as species very rarely endure for more than one geological period. An extraordinary amount of modification implies an unusually large and long-continued amount of variability, which has continually been accumulated by natural selection for the benefit of the species. But as the variability of the extraordinarily-developed part or organ has been so great and long-continued within a period not excessively remote, we might, as a general rule, expect still to find more variability in such parts than in other parts of the organisation, which have remained for a much longer period nearly constant. And this, I am convinced, is the case. That the struggle between natural selection on the one hand, and the tendency to reversion and variability on the other hand, will in the course of time cease; and that the most abnormally developed organs may be made constant, I can see no reason to doubt. Hence when an organ, however abnormal it may be, has been transmitted in approximately the same condition to many modified descendants, as in the case of the wing of the bat, it must have existed, according to my theory, for an immense period in nearly the same state; and thus it comes to be no more variable than any other structure. It is only in those cases in which the modification has been comparatively recent and extraordinarily great that we ought to find the generative variability, as it may be called, still present in a high degree. For in this case the variability will seldom as yet have been fixed by the continued selection of the individuals varying in the required manner and degree, and by the continued rejection of those tending to revert to a former and less modified condition.

The principle included in these remarks may be extended. It is notorious that specific characters are more variable than generic. To explain by a simple example what is meant. If some species in a large genus of plants had blue flowers and some had red, the colour would be only a specific character, and no one would be surprised at one of the blue species varying into red, or conversely; but if all the species had blue flowers, the colour would become a generic character, and its variation would be a more unusual circumstance. I have chosen this example because an explanation is not in this case applicable, which most naturalists would advance, namely, that specific characters are more variable than generic, because they are taken from parts of less physiological importance than those commonly used for classing genera. I believe this explanation is partly, yet only indirectly, true; I shall, however, have to return to this subject in our chapter on Classification. It would be almost superfluous to adduce evidence in support of the above statement, that specific characters are more variable than generic; but I have repeatedly noticed in works on natural history, that when an author has remarked with surprise that some important organ or part, which is generally very constant throughout large groups of species, has differed considerably in closely-allied species, that it has, also, been variable in the individuals of some of the species. And this fact shows that a character, which is generally of generic value, when it sinks in value and becomes only of specific value, often becomes variable, though its physiological importance may remain the same. Something of the same kind applies to monstrosities: at least Is. Geoffroy St. Hilaire seems to entertain no doubt, that the more an organ normally differs in the different species of the same group, the more subject it is to individual anomalies.

On the ordinary view of each species having been independently created, why should that part of the structure, which differs from the same part in other independently-created species of the same genus, be more variable than those parts which are closely alike in the several species? I do not see that any explanation can be given. But on the view of species being only strongly marked and fixed varieties, we might surely expect to find them still often continuing to vary in those parts of their structure which have varied within a moderately recent period, and which have thus come to differ. Or to state the case in another manner: the points in which all the species of a genus resemble each other, and in which they differ from the species of some other genus, are called generic characters; and these characters in common I attribute to inheritance from a common progenitor, for it can rarely have happened that natural selection will have modified several species, fitted to more or less widely-different habits, in exactly the same manner: and as these so-called generic characters have been inherited from a remote period, since that period when the species first branched off from their common progenitor, and subsequently have not varied or come to differ in any degree, or only in a slight degree, it is not probable that they should vary at the present day. On the other hand, the points in which species differ from other species of the same genus, are called specific characters; and as these specific characters have varied and come to differ within the period of the branching off of the species from a common progenitor, it is probable that they should still often be in some degree variable, at least more variable than those parts of the organisation which have for a very long period remained constant.

In connexion with the present subject, I will make only two other remarks. I think it will be admitted, without my entering on details, that secondary sexual characters are very variable; I think it also will be admitted that species of the same group differ from each other more widely in their secondary sexual characters, than in other parts of their organisation; compare, for instance, the amount of difference between the males of gallinaceous birds, in which secondary sexual characters are strongly displayed, with the amount of difference between their females; and the truth of this proposition will be granted. The cause of the original variability of secondary sexual characters is not manifest; but we can see why these characters should not have been rendered as constant and uniform as other parts of the organisation; for secondary sexual characters have been accumulated by sexual selection, which is less rigid in its action than ordinary selection, as it does not entail death, but only gives fewer offspring to the less favoured males. Whatever the cause may be of the variability of secondary sexual characters, as they are highly variable, sexual selection will have had a wide scope for action, and may thus readily have succeeded in giving to the species of the same group a greater amount of difference in their sexual characters, than in other parts of their structure.

It is a remarkable fact, that the secondary sexual differences between the two sexes of the same species are generally displayed in the very same parts of the organisation in which the different species of the same genus differ from each other. Of this fact I will give in illustration two instances, the first which happen to stand on my list; and as the differences in these cases are of a very unusual nature, the relation can hardly be accidental. The same number of joints in the tarsi is a character generally common to very large groups of beetles, but in the Engidae, as Westwood has remarked, the number varies greatly; and the number likewise differs in the two sexes of the same species: again in fossorial hymenoptera, the manner of neuration of the wings is a character of the highest importance, because common to large groups; but in certain genera the neuration differs in the different species, and likewise in the two sexes of the same species. This relation has a clear meaning on my view of the subject: I look at all the species of the same genus as having as certainly descended from the same progenitor, as have the two sexes of any one of the species. Consequently, whatever part of the structure of the common progenitor, or of its early descendants, became variable; variations of this part would it is highly probable, be taken advantage of by natural and sexual selection, in order to fit the several species to their several places in the economy of nature, and likewise to fit the two sexes of the same species to each other, or to fit the males and females to different habits of life, or the males to struggle with other males for the possession of the females.

Finally, then, I conclude that the greater variability of specific characters, or those which distinguish species from species, than of generic characters, or those which the species possess in common; that the frequent extreme variability of any part which is developed in a species in an extraordinary manner in comparison with the same part in its congeners; and the not great degree of variability in a part, however extraordinarily it may be developed, if it be common to a whole group of species; that the great variability of secondary sexual characters, and the great amount of difference in these same characters between closely allied species; that secondary sexual and ordinary specific differences are generally displayed in the same parts of the organisation, are all principles closely connected together. All being mainly due to the species of the same group having descended from a common progenitor, from whom they have inherited much in common, to parts which have recently and largely varied being more likely still to go on varying than parts which have long been inherited and have not varied, to natural selection having more or less completely, according to the lapse of time, overmastered the tendency to reversion and to further variability, to sexual selection being less rigid than ordinary selection, and to variations in the same parts having been accumulated by natural and sexual selection, and thus adapted for secondary sexual, and for ordinary specific purposes.

Distinct species present analogous variations; and a variety of one species often assumes some of the characters of an allied species, or reverts to some of the characters of an early progenitor.

These propositions will be most readily understood by looking to our domestic races. The most distinct breeds of pigeons, in countries most widely apart, present sub-varieties with reversed feathers on the head and feathers on the feet, characters not possessed by the aboriginal rock-pigeon; these then are analogous variations in two or more distinct races. The frequent presence of fourteen or even sixteen tail-feathers in the pouter, may be considered as a variation representing the normal structure of another race, the fantail. I presume that no one will doubt that all such analogous variations are due to the several races of the pigeon having inherited from a common parent the same constitution and tendency to variation, when acted on by similar unknown influences. In the vegetable kingdom we have a case of analogous variation, in the enlarged stems, or roots as commonly called, of the Swedish turnip and Ruta baga, plants which several botanists rank as varieties produced by cultivation from a common parent: if this be not so, the case will then be one of analogous variation in two so-called distinct species; and to these a third may be added, namely, the common turnip. According to the ordinary view of each species having been independently created, we should have to attribute this similarity in the enlarged stems of these three plants, not to the vera causa of community of descent, and a consequent tendency to vary in a like manner, but to three separate yet closely related acts of creation.

With pigeons, however, we have another case, namely, the occasional appearance in all the breeds, of slaty-blue birds with two black bars on the wings, a white rump, a bar at the end of the tail, with the outer feathers externally edged near their bases with white. As all these marks are characteristic of the parent rock-pigeon, I presume that no one will doubt that this is a case of reversion, and not of a new yet analogous variation appearing in the several breeds. We may I think confidently come to this conclusion, because, as we have seen, these coloured marks are eminently liable to appear in the crossed offspring of two distinct and differently coloured breeds; and in this case there is nothing in the external conditions of life to cause the reappearance of the slaty-blue, with the several marks, beyond the influence of the mere act of crossing on the laws of inheritance.

No doubt it is a very surprising fact that characters should reappear after having been lost for many, perhaps for hundreds of generations. But when a breed has been crossed only once by some other breed, the offspring occasionally show a tendency to revert in character to the foreign breed for many generations some say, for a dozen or even a score of generations. After twelve generations, the proportion of blood, to use a common expression, of any one ancestor, is only 1 in 2048; and yet, as we see, it is generally believed that a tendency to reversion is retained by this very small proportion of foreign blood. In a breed which has not been crossed, but in which both parents have lost some character which their progenitor possessed, the tendency, whether strong or weak, to reproduce the lost character might be, as was formerly remarked, for all that we can see to the contrary, transmitted for almost any number of generations. When a character which has been lost in a breed, reappears after a great number of generations, the most probable hypothesis is, not that the offspring suddenly takes after an ancestor some hundred generations distant, but that in each successive generation there has been a tendency to reproduce the character in question, which at last, under unknown favourable conditions, gains an ascendancy. For instance, it is probable that in each generation of the barb-pigeon, which produces most rarely a blue and black-barred bird, there has been a tendency in each generation in the plumage to assume this colour. This view is hypothetical, but could be supported by some facts; and I can see no more abstract improbability in a tendency to produce any character being inherited for an endless number of generations, than in quite useless or rudimentary organs being, as we all know them to be, thus inherited. Indeed, we may sometimes observe a mere tendency to produce a rudiment inherited: for instance, in the common snapdragon (Antirrhinum) a rudiment of a fifth stamen so often appears, that this plant must have an inherited tendency to produce it.

As all the species of the same genus are supposed, on my theory, to have descended from a common parent, it might be expected that they would occasionally vary in an analogous manner; so that a variety of one species would resemble in some of its characters another species; this other species being on my view only a well-marked and permanent variety. But characters thus gained would probably be of an unimportant nature, for the presence of all important characters will be governed by natural selection, in accordance with the diverse habits of the species, and will not be left to the mutual action of the conditions of life and of a similar inherited constitution. It might further be expected that the species of the same genus would occasionally exhibit reversions to lost ancestral characters. As, however, we never know the exact character of the common ancestor of a group, we could not distinguish these two cases: if, for instance, we did not know that the rock-pigeon was not feather-footed or turn-crowned, we could not have told, whether these characters in our domestic breeds were reversions or only analogous variations; but we might have inferred that the blueness was a case of reversion, from the number of the markings, which are correlated with the blue tint, and which it does not appear probable would all appear together from simple variation. More especially we might have inferred this, from the blue colour and marks so often appearing when distinct breeds of diverse colours are crossed. Hence, though under nature it must generally be left doubtful, what cases are reversions to an anciently existing character, and what are new but analogous variations, yet we ought, on my theory, sometimes to find the varying offspring of a species assuming characters (either from reversion or from analogous variation) which already occur in some members of the same group. And this undoubtedly is the case in nature.

A considerable part of the difficulty in recognising a variable species in our systematic works, is due to its varieties mocking, as it were, come of the other species of the same genus. A considerable catalogue, also, could be given of forms intermediate between two other forms, which themselves must be doubtfully ranked as either varieties or species, that the one in varying has assumed some of the characters of the other, so as to produce the intermediate form. But the best evidence is afforded by parts or organs of an important and uniform nature occasionally varying so as to acquire, in some degree, the character of the same part or organ in an allied species. I have collected a long list of such cases; but here, as before, I lie under a great disadvantage in not being able to give them. I can only repeat that such cases certainly do occur, and seem to me very remarkable.

I will, however, give one curious and complex case, not indeed as affecting any important character, but from occurring in several species of the same genus, partly under domestication and partly under nature. It is a case apparently of reversion. The ass not rarely has very distinct transverse bars on its legs, like those of a zebra: it has been asserted that these are plainest in the foal, and from inquiries which I have made, I believe this to be true. It has also been asserted that the stripe on each shoulder is sometimes double. The shoulder-stripe is certainly very variable in length and outline. A white ass, but not an albino, has been described without either spinal or shoulder-stripe; and these stripes are sometimes very obscure, or actually quite lost, in dark-coloured asses. The koulan of Pallas is said to have been seen with a double shoulder-stripe; but traces of it, as stated by Mr Blyth and others, occasionally appear: and I have been informed by Colonel Poole that foals of this species are generally striped on the legs, and faintly on the shoulder. The quagga, though so plainly barred like a zebra over the body, is without bars on the legs; but Dr Gray has figured one specimen with very distinct zebra-like bars on the hocks.

With respect to the horse, I have collected cases in England of the spinal stripe in horses of the most distinct breeds, and of all colours; transverse bars on the legs are not rare in duns, mouse-duns, and in one instance in a chestnut: a faint shoulder-stripe may sometimes be seen in duns, and I have seen a trace in a bay horse. My son made a careful examination and sketch for me of a dun Belgian cart-horse with a double stripe on each shoulder and with leg-stripes; and a man, whom I can implicitly trust, has examined for me a small dun Welch pony with three short parallel stripes on each shoulder.

In the north-west part of India the Kattywar breed of horses is so generally striped, that, as I hear from Colonel Poole, who examined the breed for the Indian Government, a horse without stripes is not considered as purely-bred. The spine is always striped; the legs are generally barred; and the shoulder-stripe, which is sometimes double and sometimes treble, is common; the side of the face, moreover, is sometimes striped. The stripes are plainest in the foal; and sometimes quite disappear in old horses. Colonel Poole has seen both gray and bay Kattywar horses striped when first foaled. I have, also, reason to suspect, from information given me by Mr. W. W. Edwards, that with the English race-horse the spinal stripe is much commoner in the foal than in the full-grown animal. Without here entering on further details, I may state that I have collected cases of leg and shoulder stripes in horses of very different breeds, in various countries from Britain to Eastern China; and from Norway in the north to the Malay Archipelago in the south. In all parts of the world these stripes occur far oftenest in duns and mouse-duns; by the term dun a large range of colour is included, from one between brown and black to a close approach to cream-colour.

I am aware that Colonel Hamilton Smith, who has written on this subject, believes that the several breeds of the horse have descended from several aboriginal species one of which, the dun, was striped; and that the above-described appearances are all due to ancient crosses with the dun stock. But I am not at all satisfied with this theory, and should be loth to apply it to breeds so distinct as the heavy Belgian cart-horse, Welch ponies, cobs, the lanky Kattywar race, &c., inhabiting the most distant parts of the world.

Now let us turn to the effects of crossing the several species of the horse-genus. Rollin asserts, that the common mule from the ass and horse is particularly apt to have bars on its legs. I once saw a mule with its legs so much striped that any one at first would have thought that it must have been the product of a zebra; and Mr. W. C. Martin, in his excellent treatise on the horse, has given a figure of a similar mule. In four coloured drawings, which I have seen, of hybrids between the ass and zebra, the legs were much more plainly barred than the rest of the body; and in one of them there was a double shoulder-stripe. In Lord Moreton's famous hybrid from a chestnut mare and male quagga, the hybrid, and even the pure offspring subsequently produced from the mare by a black Arabian sire, were much more plainly barred across the legs than is even the pure quagga. Lastly, and this is another most remarkable case, a hybrid has been figured by Dr Gray (and he informs me that he knows of a second case) from the ass and the hemionus; and this hybrid, though the ass seldom has stripes on its legs and the hemionus has none and has not even a shoulder-stripe, nevertheless had all four legs barred, and had three short shoulder-stripes, like those on the dun Welch pony, and even had some zebra-like stripes on the sides of its face. With respect to this last fact, I was so convinced that not even a stripe of colour appears from what would commonly be called an accident, that I was led solely from the occurrence of the face-stripes on this hybrid from the ass and hemionus, to ask Colonel Poole whether such face-stripes ever occur in the eminently striped Kattywar breed of horses, and was, as we have seen, answered in the affirmative.

What now are we to say to these several facts? We see several very distinct species of the horse-genus becoming, by simple variation, striped on the legs like a zebra, or striped on the shoulders like an ass. In the horse we see this tendency strong whenever a dun tint appears a tint which approaches to that of the general colouring of the other species of the genus. The appearance of the stripes is not accompanied by any change of form or by any other new character. We see this tendency to become striped most strongly displayed in hybrids from between several of the most distinct species. Now observe the case of the several breeds of pigeons: they are descended from a pigeon (including two or three sub-species or geographical races) of a bluish colour, with certain bars and other marks; and when any breed assumes by simple variation a bluish tint, these bars and other marks invariably reappear; but without any other change of form or character. When the oldest and truest breeds of various colours are crossed, we see a strong tendency for the blue tint and bars and marks to reappear in the mongrels. I have stated that the most probable hypothesis to account for the reappearance of very ancient characters, is that there is a tendency in the young of each successive generation to produce the long-lost character, and that this tendency, from unknown causes, sometimes prevails. And we have just seen that in several species of the horse-genus the stripes are either plainer or appear more commonly in the young than in the old. Call the breeds of pigeons, some of which have bred true for centuries, species; and how exactly parallel is the case with that of the species of the horse-genus! For myself, I venture confidently to look back thousands on thousands of generations, and I see an animal striped like a zebra, but perhaps otherwise very differently constructed, the common parent of our domestic horse, whether or not it be descended from one or more wild stocks, of the ass, the hemionus, quagga, and zebra.

He who believes that each equine species was independently created, will, I presume, assert that each species has been created with a tendency to vary, both under nature and under domestication, in this particular manner, so as often to become striped like other species of the genus; and that each has been created with a strong tendency, when crossed with species inhabiting distant quarters of the world, to produce hybrids resembling in their stripes, not their own parents, but other species of the genus. To admit this view is, as it seems to me, to reject a real for an unreal, or at least for an unknown, cause. It makes the works of God a mere mockery and deception; I would almost as soon believe with the old and ignorant cosmogonists, that fossil shells had never lived, but had been created in stone so as to mock the shells now living on the sea-shore.

Summary

Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this or that part differs, more or less, from the same part in the parents. But whenever we have the means of instituting a comparison, the same laws appear to have acted in producing the lesser differences between varieties of the same species, and the greater differences between species of the same genus. The external conditions of life, as climate and food, &c., seem to have induced some slight modifications. Habit in producing constitutional differences, and use in strengthening, and disuse in weakening and diminishing organs, seem to have been more potent in their effects. Homologous parts tend to vary in the same way, and homologous parts tend to cohere. Modifications in hard parts and in external parts sometimes affect softer and internal parts. When one part is largely developed, perhaps it tends to draw nourishment from the adjoining parts; and every part of the structure which can be saved without detriment to the individual, will be saved. Changes of structure at an early age will generally affect parts subsequently developed; and there are very many other correlations of growth, the nature of which we are utterly unable to understand. Multiple parts are variable in number and in structure, perhaps arising from such parts not having been closely specialized to any particular function, so that their modifications have not been closely checked by natural selection. It is probably from this same cause that organic beings low in the scale of nature are more variable than those which have their whole organisation more specialized, and are higher in the scale. Rudimentary organs, from being useless, will be disregarded by natural selection, and hence probably are variable. Specific characters that is, the characters which have come to differ since the several species of the same genus branched off from a common parent are more variable than generic characters, or those which have long been inherited, and have not differed within this same period. In these remarks we have referred to special parts or organs being still variable, because they have recently varied and thus come to differ; but we have also seen in the second Chapter that the same principle applies to the whole individual; for in a district where many species of any genus are found that is, where there has been much former variation and differentiation, or where the manufactory of new specific forms has been actively at work there, on an average, we now find most varieties or incipient species. Secondary sexual characters are highly variable, and such characters differ much in the species of the same group. Variability in the same parts of the organisation has generally been taken advantage of in giving secondary sexual differences to the sexes of the same species, and specific differences to the several species of the same genus. Any part or organ developed to an extraordinary size or in an extraordinary manner, in comparison with the same part or organ in the allied species, must have gone through an extraordinary amount of modification since the genus arose; and thus we can understand why it should often still be variable in a much higher degree than other parts; for variation is a long-continued and slow process, and natural selection will in such cases not as yet have had time to overcome the tendency to further variability and to reversion to a less modified state. But when a species with any extraordinarily-developed organ has become the parent of many modified descendants which on my view must be a very slow process, requiring a long lapse of time in this case, natural selection may readily have succeeded in giving a fixed character to the organ, in however extraordinary a manner it may be developed. Species inheriting nearly the same constitution from a common parent and exposed to similar influences will naturally tend to present analogous variations, and these same species may occasionally revert to some of the characters of their ancient progenitors. Although new and important modifications may not arise from reversion and analogous variation, such modifications will add to the beautiful and harmonious diversity of nature.

Whatever the cause may be of each slight difference in the offspring from their parents and a cause for each must exist it is the steady accumulation, through natural selection, of such differences, when beneficial to the individual, that gives rise to all the more important modifications of structure, by which the innumerable beings on the face of this earth are enabled to struggle with each other, and the best adapted to survive. 
LONG before having arrived at this part of my work, a crowd of difficulties will have occurred to the reader. Some of them are so grave that to this day I can never reflect on them without being staggered; but, to the best of my judgment, the greater number are only apparent, and those that are real are not, I think, fatal to my theory.

These difficulties and objections may be classed under the following heads:-Firstly, why, if species have descended from other species by insensibly fine gradations, do we not everywhere see innumerable transitional forms? Why is not all nature in confusion instead of the species being, as we see them, well defined?

Secondly, is it possible that an animal having, for instance, the structure and habits of a bat, could have been formed by the modification of some animal with wholly different habits? Can we believe that natural selection could produce, on the one hand, organs of trifling importance, such as the tail of a giraffe, which serves as a fly-flapper, and, on the other hand, organs of such wonderful structure, as the eye, of which we hardly as yet fully understand the inimitable perfection?

Thirdly, can instincts be acquired and modified through natural selection? What shall we say to so marvellous an instinct as that which leads the bee to make cells, which have practically anticipated the discoveries of profound mathematicians?

Fourthly, how can we account for species, when crossed, being sterile and producing sterile offspring, whereas, when varieties are crossed, their fertility is unimpaired?

The two first heads shall be here discussed Instinct and Hybridism in separate chapters.

On the absence or rarity of transitional varieties. As natural selection acts solely by the preservation of profitable modifications, each new form will tend in a fully-stocked country to take the place of, and finally to exterminate, its own less improved parent or other less-favoured forms with which it comes into competition. Thus extinction and natural selection will, as we have seen, go hand in hand. Hence, if we look at each species as descended from some other unknown form, both the parent and all the transitional varieties will generally have been exterminated by the very process of formation and perfection of the new form.

But, as by this theory innumerable transitional forms must have existed, why do we not find them embedded in countless numbers in the crust of the earth? It will be much more convenient to discuss this question in the chapter on the Imperfection of the geological record; and I will here only state that I believe the answer mainly lies in the record being incomparably less perfect than is generally supposed; the imperfection of the record being chiefly due to organic beings not inhabiting profound depths of the sea, and to their remains being embedded and preserved to a future age only in masses of sediment sufficiently thick and extensive to withstand an enormous amount of future degradation; and such fossiliferous masses can be accumulated only where much sediment is deposited on the shallow bed of the sea, whilst it slowly subsides. These contingencies will concur only rarely, and after enormously long intervals. Whilst the bed of the sea is stationary or is rising, or when very little sediment is being deposited, there will be blanks in our geological history. The crust of the earth is a vast museum; but the natural collections have been made only at intervals of time immensely remote.

But it may be urged that when several closely-allied species inhabit the same territory we surely ought to find at the present time many transitional forms. Let us take a simple case: in travelling from north to south over a continent, we generally meet at successive intervals with closely allied or representative species, evidently filling nearly the same place in the natural economy of the land. These representative species often meet and interlock; and as the one becomes rarer and rarer, the other becomes more and more frequent, till the one replaces the other. But if we compare these species where they intermingle, they are generally as absolutely distinct from each other in every detail of structure as are specimens taken from the metropolis inhabited by each. By my theory these allied species have descended from a common parent; and during the process of modification, each has become adapted to the conditions of life of its own region, and has supplanted and exterminated its original parent and all the transitional varieties between its past and present states. Hence we ought not to expect at the present time to meet with numerous transitional varieties in each region, though they must have existed there, and may be embedded there in a fossil condition. But in the intermediate region, having intermediate conditions of life, why do we not now find closely-linking intermediate varieties? This difficulty for a long time quite confounded me. But I think it can be in large part explained.

In the first place we should be extremely cautious in inferring, because an area is now continuous, that it has been continuous during a long period. Geology would lead us to believe that almost every continent has been broken up into islands even during the later tertiary periods; and in such islands distinct species might have been separately formed without the possibility of intermediate varieties existing in the intermediate zones. By changes in the form of the land and of climate, marine areas now continuous must often have existed within recent times in a far less continuous and uniform condition than at present. But I will pass over this way of escaping from the difficulty; for I believe that many perfectly defined species have been formed on strictly continuous areas; though I do not doubt that the formerly broken condition of areas now continuous has played an important part in the formation of new species, more especially with freely-crossing and wandering animals.

In looking at species as they are now distributed over a wide area, we generally find them tolerably numerous over a large territory, then becoming somewhat abruptly rarer and rarer on the confines, and finally disappearing. Hence the neutral territory between two representative species is generally narrow in comparison with the territory proper to each. We see the same fact in ascending mountains, and sometimes it is quite remarkable how abruptly, as Alph. De Candolle has observed, a common alpine species disappears. The same fact has been noticed by Forbes in sounding the depths of the sea with the dredge. To those who look at climate and the physical conditions of life as the all-important elements of distribution, these facts ought to cause surprise, as climate and height or depth graduate away insensibly. But when we bear in mind that almost every species, even in its metropolis, would increase immensely in numbers, were it not for other competing species; that nearly all either prey on or serve as prey for others; in short, that each organic being is either directly or indirectly related in the most important manner to other organic beings, we must see that the range of the inhabitants of any country by no means exclusively depends on insensibly changing physical conditions, but in large part on the presence of other species, on which it depends, or by which it is destroyed, or with which it comes into competition; and as these species are already defined objects (however they may have become so), not blending one into another by insensible gradations, the range of any one species, depending as it does on the range of others, will tend to be sharply defined. Moreover, each species on the confines of its range, where it exists in lessened numbers, will, during fluctuations in the number of its enemies or of its prey, or in the seasons, be extremely liable to utter extermination; and thus its geographical range will come to be still more sharply defined.

If I am right in believing that allied or representative species, when inhabiting a continuous area, are generally so distributed that each has a wide range, with a comparatively narrow neutral territory between them, in which they become rather suddenly rarer and rarer; then, as varieties do not essentially differ from species, the same rule will probably apply to both; and if we in imagination adapt a varying species to a very large area, we shall have to adapt two varieties to two large areas, and a third variety to a narrow intermediate zone. The intermediate variety, consequently, will exist in lesser numbers from inhabiting a narrow and lesser area; and practically, as far as I can make out, this rule holds good with varieties in a state of nature. I have met with striking instances of the rule in the case of varieties intermediate between well-marked varieties in the genus Balanus. And it would appear from information given me by Mr Watson, Dr Asa Gray, and Mr Wollaston, that generally when varieties intermediate between two other forms occur, they are much rarer numerically than the forms which they connect. Now, if we may trust these facts and inferences, and therefore conclude that varieties linking two other varieties together have generally existed in lesser numbers than the forms which they connect, then, I think, we can understand why intermediate varieties should not endure for very long periods; why as a general rule they should be exterminated and disappear, sooner than the forms which they originally linked together.

For any form existing in lesser numbers would, as already remarked, run a greater chance of being exterminated than one existing in large numbers; and in this particular case the intermediate form would be eminently liable to the inroads of closely allied forms existing on both sides of it. But a far more important consideration, as I believe, is that, during the process of further modification, by which two varieties are supposed on my theory to be converted and perfected into two distinct species, the two which exist in larger numbers from inhabiting larger areas, will have a great advantage over the intermediate variety, which exists in smaller numbers in a narrow and intermediate zone. For forms existing in larger numbers will always have a better chance, within any given period, of presenting further favourable variations for natural selection to seize on, than will the rarer forms which exist in lesser numbers. Hence, the more common forms, in the race for life, will tend to beat and supplant the less common forms, for these will be more slowly modified and improved. It is the same principle which, as I believe, accounts for the common species in each country, as shown in the second chapter, presenting on an average a greater number of well-marked varieties than do the rarer species. I may illustrate what I mean by supposing three varieties of sheep to be kept, one adapted to an extensive mountainous region; a second to a comparatively narrow, hilly tract; and a third to wide plains at the base; and that the inhabitants are all trying with equal steadiness and skill to improve their stocks by selection; the chances in this case will be strongly in favour of the great holders on the mountains or on the plains improving their breeds more quickly than the small holders on the intermediate narrow, hilly tract; and consequently the improved mountain or plain breed will soon take the place of the less improved hill breed; and thus the two breeds, which originally existed in greater numbers, will come into close contact with each other, without the interposition of the supplanted, intermediate hill-variety.

To sum up, I believe that species come to be tolerably well-defined objects, and do not at any one period present an inextricable chaos of varying and intermediate links: firstly, because new varieties are very slowly formed, for variation is a very slow process, and natural selection can do nothing until favourable variations chance to occur, and until a place in the natural polity of the country can be better filled by some modification of some one or more of its inhabitants. And such new places will depend on slow changes of climate, or on the occasional immigration of new inhabitants, and, probably, in a still more important degree, on some of the old inhabitants becoming slowly modified, with the new forms thus produced and the old ones acting and reacting on each other. So that, in any one region and at any one time, we ought only to see a few species presenting slight modifications of structure in some degree permanent; and this assuredly we do see.

Secondly, areas now continuous must often have existed within the recent period in isolated portions, in which many forms, more especially amongst the classes which unite for each birth and wander much, may have separately been rendered sufficiently distinct to rank as representative species. In this case, intermediate varieties between the several representative species and their common parent, must formerly have existed in each broken portion of the land, but these links will have been supplanted and exterminated during the process of natural selection, so that they will no longer exist in a living state.

Thirdly, when two or more varieties have been formed in different portions of a strictly continuous area, intermediate varieties will, it is probable, at first have been formed in the intermediate zones, but they will generally have had a short duration. For these intermediate varieties will, from reasons already assigned (namely from what we know of the actual distribution of closely allied or representative species, and likewise of acknowledged varieties), exist in the intermediate zones in lesser numbers than the varieties which they tend to connect. From this cause alone the intermediate varieties will be liable to accidental extermination; and during the process of further modification through natural selection, they will almost certainly be beaten and supplanted by the forms which they connect; for these from existing in greater numbers will, in the aggregate, present more variation, and thus be further improved through natural selection and gain further advantages.

Lastly, looking not to any one time, but to all time, if my theory be true, numberless intermediate varieties, linking most closely all the species of the same group together, must assuredly have existed; but the very process of natural selection constantly tends, as has been so often remarked, to exterminate the parent forms and the intermediate links. Consequently evidence of their former existence could be found only amongst fossil remains, which are preserved, as we shall in a future chapter attempt to show, in an extremely imperfect and intermittent record.

On the origin and transitions of organic beings with peculiar habits and structure. It has been asked by the opponents of such views as I hold, how, for instance, a land carnivorous animal could have been converted into one with aquatic habits; for how could the animal in its transitional state have subsisted? It would be easy to show that within the same group carnivorous animals exist having every intermediate grade between truly aquatic and strictly terrestrial habits; and as each exists by a struggle for life, it is clear that each is well adapted in its habits to its place in nature. Look at the Mustela vison of North America, which has webbed feet and which resembles an otter in its fur, short legs, and form of tail; during summer this animal dives for and preys on fish, but during the long winter it leaves the frozen waters, and preys like other polecats on mice and land animals. If a different case had been taken, and it had been asked how an insectivorous quadruped could possibly have been converted into a flying bat, the question would have been far more difficult, and I could have given no answer. Yet I think such difficulties have very little weight.

Here, as on other occasions, I lie under a heavy disadvantage, for out of the many striking cases which I have collected, I can give only one or two instances of transitional habits and structures in closely allied species of the same genus; and of diversified habits, either constant or occasional, in the same species. And it seems to me that nothing less than a long list of such cases is sufficient to lessen the difficulty in any particular case like that of the bat.

Look at the family of squirrels; here we have the finest gradation from animals with their tails only slightly flattened, and from others, as Sir J. Richardson has remarked, with the posterior part of their bodies rather wide and with the skin on their flanks rather full, to the so-called flying squirrels; and flying squirrels have their limbs and even the base of the tail united by a broad expanse of skin, which serves as a parachute and allows them to glide through the air to an astonishing distance from tree to tree. We cannot doubt that each structure is of use to each kind of squirrel in its own country, by enabling it to escape birds or beasts of prey, or to collect food more quickly, or, as there is reason to believe, by lessening the danger from occasional falls. But it does not follow from this fact that the structure of each squirrel is the best that it is possible to conceive under all natural conditions. Let the climate and vegetation change, let other competing rodents or new beasts of prey immigrate, or old ones become modified, and all analogy would lead us to believe that some at least of the squirrels would decrease in numbers or become exterminated, unless they also became modified and improved in structure in a corresponding manner. Therefore, I can see no difficulty, more especially under changing conditions of life, in the continued preservation of individuals with fuller and fuller flank-membranes, each modification being useful, each being propagated, until by the accumulated effects of this process of natural selection, a perfect so-called flying squirrel was produced.

Now look at the Galeopithecus or flying lemur, which formerly was falsely ranked amongst bats. It has an extremely wide flank-membrane, stretching from the corners of the jaw to the tail, and including the limbs and the elongated fingers: the flank membrane is, also, furnished with an extensor muscle. Although no graduated links of structure, fitted for gliding through the air, now connect the Galeopithecus with the other Lemuridae, yet I can see no difficulty in supposing that such links formerly existed, and that each had been formed by the same steps as in the case of the less perfectly gliding squirrels; and that each grade of structure had been useful to its possessor. Nor can I see any insuperable difficulty in further believing it possible that the membrane-connected fingers and fore-arm of the Galeopithecus might be greatly lengthened by natural selection; and this, as far as the organs of flight are concerned, would convert it into a bat. In bats which have the wing-membrane extended from the top of the shoulder to the tail, including the hind-legs, we perhaps see traces of an apparatus originally constructed for gliding through the air rather than for flight.

If about a dozen genera of birds had become extinct or were unknown, who would have ventured to have surmised that birds might have existed which used their wings solely as flappers, like the logger-headed duck (Micropterus of Eyton); as fins in the water and front legs on the land, like the penguin; as sails, like the ostrich; and functionally for no purpose, like the Apteryx. Yet the structure of each of these birds is good for it, under the conditions of life to which it is exposed, for each has to live by a struggle; but it is not necessarily the best possible under all possible conditions. It must not be inferred from these remarks that any of the grades of wing-structure here alluded to, which perhaps may all have resulted from disuse, indicate the natural steps by which birds have acquired their perfect power of flight; but they serve, at least, to show what diversified means of transition are possible.

Seeing that a few members of such water-breathing classes as the Crustacea and Mollusca are adapted to live on the land, and seeing that we have flying birds and mammals, flying insects of the most diversified types, and formerly had flying reptiles, it is conceivable that flying-fish, which now glide far through the air, slightly rising and turning by the aid of their fluttering fins, might have been modified into perfectly winged animals. If early transitional state they had been inhabitants of the open ocean, and had used their incipient organs of flight exclusively, as far as we know, to escape being devoured by other fish?

When we see any structure highly perfected for any particular habit, as the wings of a bird for flight, we should bear in mind that animals displaying early transitional grades of the structure will seldom continue to exist to the present day, for they will have been supplanted by the very process of perfection through natural selection. Furthermore, we may conclude that transitional grades between structures fitted for very different habits of life will rarely have been developed at an early period in great numbers and under many subordinate forms. Thus, to return to our imaginary illustration of the flying-fish, it does not seem probable that fishes capable of true flight would have been developed under many subordinate forms, for taking prey of many kinds in many ways, on the land and in the water, until their organs of flight had come to a high stage of perfection, so as to have given them a decided advantage over other animals in the battle for life. Hence the chance of discovering species with transitional grades of structure in a fossil condition will always be less, from their having existed in lesser numbers, than in the case of species with fully developed structures.

I will now give two or three instances of diversified and of changed habits in the individuals of the same species. When either case occurs, it would be easy for natural selection to fit the animal, by some modification of its structure, for its changed habits, or exclusively for one of its several different habits. But it is difficult to tell, and immaterial for us, whether habits generally change first and structure afterwards; or whether slight modifications of structure lead to changed habits; both probably often change almost simultaneously. Of cases of changed habits it will suffice merely to allude to that of the many British insects which now feed on exotic plants, or exclusively on artificial substances. Of diversified habits innumerable instances could be given: I have often watched a tyrant flycatcher (Saurophagus sulphuratus) in South America, hovering over one spot and then proceeding to another, like a kestrel, and at other times standing stationary on the margin of water, and then dashing like a kingfisher at a fish. In our own country the larger titmouse (Parus major) may be seen climbing branches, almost like a creeper; it often, like a shrike, kills small birds by blows on the head; and I have many times seen and heard it hammering the seeds of the yew on a branch, and thus breaking them like a nuthatch. In North America the black bear was seen by Hearne swimming for hours with widely open mouth, thus catching, like a whale, insects in the water. Even in so extreme a case as this, if the supply of insects were constant, and if better adapted competitors did not already exist in the country, I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale.

As we sometimes see individuals of a species following habits widely different from those both of their own species and of the other species of the same genus, we might expect, on my theory, that such individuals would occasionally have given rise to new species, having anomalous habits, and with their structure either slightly or considerably modified from that of their proper type. And such instances do occur in nature. Can a more striking instance of adaptation be given than that of a woodpecker for climbing trees and for seizing insects in the chinks of the bark? Yet in North America there are woodpeckers which feed largely on fruit, and others with elongated wings which chase insects on the wing; and on the plains of La Plata, where not a tree grows, there is a woodpecker, which in every essential part of its organisation, even in its colouring, in the harsh tone of its voice, and undulatory flight, told me plainly of its close blood-relationship to our common species; yet it is a woodpecker which never climbs a tree!

Petrels are the most aërial and oceanic of birds, yet in the quiet Sounds of Tierra del Fuego, the Puffinuria berardi, in its general habits, in its astonishing power of diving, its manner of swimming, and of flying when unwillingly it takes flight, would be mistaken by any one for an auk or grebe; nevertheless, it is essentially a petrel, but with many parts of its organisation profoundly modified. On the other hand, the acutest observer by examining the dead body of the water-ouzel would never have suspected its sub-aquatic habits; yet this anomalous member of the strictly terrestrial thrush family wholly subsists by diving, grasping the stones with its feet and using its wings under water.

He who believes that each being has been created as we now see it, must occasionally have felt surprise when he has met with an animal having habits and structure not at all in agreement. What can be plainer than that the webbed feet of ducks and geese are formed for swimming; yet there are upland geese with webbed feet which rarely or never go near the water; and no one except Audubon has seen the frigate-bird, which has all its four toes webbed, alight on the surface of the sea. On the other hand, grebes and coots are eminently aquatic, although their toes are only bordered by membrane. What seems plainer than that the long toes of grallatores are formed for walking over swamps and floating plants, yet the water-hen is nearly as aquatic as the coot; and the landrail nearly as terrestrial as the quail or partridge. In such cases, and many others could be given, habits have changed without a corresponding change of structure. The webbed feet of the upland goose may be said to have become rudimentary in function, though not in structure. In the frigate-bird, the deeply-scooped membrane between the toes shows that structure has begun to change.

He who believes in separate and innumerable acts of creation will say, that in these cases it has pleased the Creator to cause a being of one type to take the place of one of another type; but this seems to me only restating the fact in dignified language. He who believes in the struggle for existence and in the principle of natural selection, will acknowledge that every organic being is constantly endeavouring to increase in numbers; and that if any one being vary ever so little, either in habits or structure, and thus gain an advantage over some other inhabitant of the country, it will seize on the place of that inhabitant, however different it may be from its own place. Hence it will cause him no surprise that there should be geese and frigate-birds with webbed feet, either living on the dry land or most rarely alighting on the water; that there should be long-toed corncrakes living in meadows instead of in swamps; that there should be woodpeckers where not a tree grows; that there should be diving thrushes, and petrels with the habits of auks.

Organs of extreme perfection and complication. To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree. Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself first originated; but I may remark that several facts make me suspect that any sensitive nerve may be rendered sensitive to light, and likewise to those coarser vibrations of the air which produce sound.

In looking for the gradations by which an organ in any species has been perfected, we ought to look exclusively to its lineal ancestors; but this is scarcely ever possible, and we are forced in each case to look to species of the same group, that is to the collateral descendants from the same original parent-form, in order to see what gradations are possible, and for the chance of some gradations having been transmitted from the earlier stages of descent, in an unaltered or little altered condition. Amongst existing Vertebrata, we find but a small amount of gradation in the structure of the eye, and from fossil species we can learn nothing on this head. In this great class we should probably have to descend far beneath the lowest known fossiliferous stratum to discover the earlier stages, by which the eye has been perfected.

In the Articulata we can commence a series with an optic nerve merely coated with pigment, and without any other mechanism; and from this low stage, numerous gradations of structure, branching off in two fundamentally different lines, can be shown to exist, until we reach a moderately high stage of perfection. In certain crustaceans, for instance, there is a double cornea, the inner one divided into facets, within each of which there is a lens shaped swelling. In other crustaceans the transparent cones which are coated by pigment, and which properly act only by excluding lateral pencils of light, are convex at their upper ends and must act by convergence; and at their lower ends there seems to be an imperfect vitreous substance. With these facts, here far too briefly and imperfectly given, which show that there is much graduated diversity in the eyes of living crustaceans, and bearing in mind how small the number of living animals is in proportion to those which have become extinct, I can see no very great difficulty (not more than in the case of many other structures) in believing that natural selection has converted the simple apparatus of an optic nerve merely coated with pigment and invested by transparent membrane, into an optical instrument as perfect as is possessed by any member of the great Articulate class.

He who will go thus far, if he find on finishing this treatise that large bodies of facts, otherwise inexplicable, can be explained by the theory of descent, ought not to hesitate to go further, and to admit that a structure even as perfect as the eye of an eagle might be formed by natural selection, although in this case he does not know any of the transitional grades. His reason ought to conquer his imagination; though I have felt the difficulty far too keenly to be surprised at any degree of hesitation in extending the principle of natural selection to such startling lengths.

It is scarcely possible to avoid comparing the eye to a telescope. We know that this instrument has been perfected by the long-continued efforts of the highest human intellects; and we naturally infer that the eye has been formed by a somewhat analogous process. But may not this inference be presumptuous? Have we any right to assume that the Creator works by intellectual powers like those of man? If we must compare the eye to an optical instrument, we ought in imagination to take a thick layer of transparent tissue, with a nerve sensitive to light beneath, and then suppose every part of this layer to be continually changing slowly in density, so as to separate into layers of different densities and thicknesses, placed at different distances from each other, and with the surfaces of each layer slowly changing in form. Further we must suppose that there is a power always intently watching each slight accidental alteration in the transparent layers; and carefully selecting each alteration which, under varied circumstances, may in any way, or in any degree, tend to produce a distincter image. We must suppose each new state of the instrument to be multiplied by the million; and each to be preserved till a better be produced, and then the old ones to be destroyed. In living bodies, variation will cause the slight alterations, generation will multiply them almost infinitely, and natural selection will pick out with unerring skill each improvement. Let this process go on for millions on millions of years; and during each year on millions of individuals of many kinds; and may we not believe that a living optical instrument might thus be formed as superior to one of glass, as the works of the Creator are to those of man?

If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find out no such case. No doubt many organs exist of which we do not know the transitional grades, more especially if we look to much-isolated species, round which, according to my theory, there has been much extinction. Or again, if we look to an organ common to all the members of a large class, for in this latter case the organ must have been first formed at an extremely remote period, since which all the many members of the class have been developed; and in order to discover the early transitional grades through which the organ has passed, we should have to look to very ancient ancestral forms, long since become extinct.

We should be extremely cautious in concluding that an organ could not have been formed by transitional gradations of some kind. Numerous cases could be given amongst the lower animals of the same organ performing at the same time wholly distinct functions; thus the alimentary canal respires, digests, and excretes in the larva of the dragon-fly and in the fish Cobites. In the Hydra, the animal may be turned inside out, and the exterior surface will then digest and the stomach respire. In such cases natural selection might easily specialise, if any advantage were thus gained, a part or organ, which had performed two functions, for one function alone, and thus wholly change its nature by insensible steps. Two distinct organs sometimes perform simultaneously the same function in the same individual; to give one instance, there are fish with gills or branchiae that breathe the air dissolved in the water, at the same time that they breathe free air in their swimbladders, this latter organ having a ductus pneumaticus for its supply, and being divided by highly vascular partitions. In these cases, one of the two organs might with ease be modified and perfected so as to perform all the work by itself, being aided during the process of modification by the other organ; and then this other organ might be modified for some other and quite distinct purpose, or be quite obliterated.

The illustration of the swimbladder in fishes is a good one, because it shows us clearly the highly important fact that an organ originally constructed for one purpose, namely flotation, may be converted into one for a wholly different purpose, namely respiration. The swimbladder has, also, been worked in as an accessory to the auditory organs of certain fish, or, for I do not know which view is now generally held, a part of the auditory apparatus has been worked in as a complement to the swimbladder. All physiologists admit that the swimbladder is homologous, or 'ideally similar,' in position and structure with the lungs of the higher vertebrate animals: hence there seems to me to be no great difficulty in believing that natural selection has actually converted a swimbladder into a lung, or organ used exclusively for respiration.

I can, indeed, hardly doubt that all vertebrate animals having true lungs have descended by ordinary generation from an ancient prototype, of which we know nothing, furnished with a floating apparatus or swimbladder. We can thus, as I infer from Professor Owen's interesting description of these parts, understand the strange fact that every particle of food and drink which we swallow has to pass over the orifice of the trachea, with some risk of falling into the lungs, notwithstanding the beautiful contrivance by which the glottis is closed. In the higher Vertebrata the branchiae have wholly disappeared the slits on the sides of the neck and the loop-like course of the arteries still marking in the embryo their former position. But it is conceivable that the now utterly lost branchiae might have been gradually worked in by natural selection for some quite distinct purpose: in the same manner as, on the view entertained by some naturalists that the branchiae and dorsal scales of Annelids are homologous with the wings and wing-covers of insects, it is probable that organs which at a very ancient period served for respiration have been actually converted into organs of flight.

In considering transitions of organs, it is so important to bear in mind the probability of conversion from one function to another, that I will give one more instance. Pedunculated cirripedes have two minute folds of skin, called by me the ovigerous frena, which serve, through the means of a sticky secretion, to retain the eggs until they are hatched within the sack. These cirripedes have no branchiae, the whole surface of the body and sack, including the small frena, serving for respiration. The Balanidae or sessile cirripedes, on the other hand, have no ovigerous frena, the eggs lying loose at the bottom of the sack, in the well-enclosed shell; but they have large folded branchiae. Now I think no one will dispute that the ovigerous frena in the one family are strictly homologous with the branchiae of the other family; indeed, they graduate into each other. Therefore I do not doubt that little folds of skin, which originally served as ovigerous frena, but which, likewise, very slightly aided the act of respiration, have been gradually converted by natural selection into branchiae, simply through an increase in their size and the obliteration of their adhesive glands. If all pedunculated cirripedes had become extinct, and they have already suffered far more extinction than have sessile cirripedes, who would ever have imagined that the branchiae in this latter family had originally existed as organs for preventing the ova from being washed out of the sack?

Although we must be extremely cautious in concluding that any organ could not possibly have been produced by successive transitional gradations, yet, undoubtedly, grave cases of difficulty occur, some of which will be discussed in my future work.

One of the gravest is that of neuter insects, which are often very differently constructed from either the males or fertile females; but this case will be treated of in the next chapter. The electric organs of fishes offer another case of special difficulty; it is impossible to conceive by what steps these wondrous organs have been produced; but, as Owen and others have remarked, their intimate structure closely resembles that of common muscle; and as it has lately been shown that Rays have an organ closely analogous to the electric apparatus, and yet do not, as Matteuchi asserts, discharge any electricity, we must own that we are far too ignorant to argue that no transition of any kind is possible.

The electric organs offer another and even more serious difficulty; for they occur in only about a dozen fishes, of which several are widely remote in their affinities. Generally when the same organ appears in several members of the same class, especially if in members having very different habits of life, we may attribute its presence to inheritance from a common ancestor; and its absence in some of the members to its loss through disuse or natural selection. But if the electric organs had been inherited from one ancient progenitor thus provided, we might have expected that all electric fishes would have been specially related to each other. Nor does geology at all lead to the belief that formerly most fishes had electric organs, which most of their modified descendants have lost. The presence of luminous organs in a few insects, belonging to different families and orders, offers a parallel case of difficulty. Other cases could be given; for instance in plants, the very curious contrivance of a mass of pollen-grains, borne on a foot-stalk with a sticky gland at the end, is the same in Orchis and Asclepias, genera almost as remote as possible amongst flowering plants. In all these cases of two very distinct species furnished with apparently the same anomalous organ, it should be observed that, although the general appearance and function of the organ may be the same, yet some fundamental difference can generally be detected. I am inclined to believe that in nearly the same way as two men have sometimes independently hit on the very same invention, so natural selection, working for the good of each being and taking advantage of analogous variations, has sometimes modified in very nearly the same manner two parts in two organic beings, which owe but little of their structure in common to inheritance from the same ancestor.

Although in many cases it is most difficult to conjecture by what transitions an organ could have arrived at its present state; yet, considering that the proportion of living and known forms to the extinct and unknown is very small, I have been astonished how rarely an organ can be named, towards which no transitional grade is known to lead. The truth of this remark is indeed shown by that old canon in natural history of 'Natura non facit saltum.' We meet with this admission in the writings of almost every experienced naturalist; or, as Milne Edwards has well expressed it, nature is prodigal in variety, but niggard in innovation. Why, on the theory of Creation, should this be so? Why should all the parts and organs of many independent beings, each supposed to have been separately created for its proper place in nature, be so invariably linked together by graduated steps? Why should not Nature have taken a leap from structure to structure? On the theory of natural selection, we can clearly understand why she should not; for natural selection can act only by taking advantage of slight successive variations; she can never take a leap, but must advance by the shortest and slowest steps.

Organs of little apparent importance. As natural selection acts by life and death, by the preservation of individuals with any favourable variation, and by the destruction of those with any unfavourable deviation of structure, I have sometimes felt much difficulty in understanding the origin of simple parts, of which the importance does not seem sufficient to cause the preservation of successively varying individuals. I have sometimes felt as much difficulty, though of a very different kind, on this head, as in the case of an organ as perfect and complex as the eye.

In the first place, we are much too ignorant in regard to the whole economy of any one organic being, to say what slight modifications would be of importance or not. In a former chapter I have given instances of most trifling characters, such as the down on fruit and the colour of the flesh, which, from determining the attacks of insects or from being correlated with constitutional differences, might assuredly be acted on by natural selection. The tail of the giraffe looks like an artificially constructed fly-flapper; and it seems at first incredible that this could have been adapted for its present purpose by successive slight modifications, each better and better, for so trifling an object as driving away flies; yet we should pause before being too positive even in this case, for we know that the distribution and existence of cattle and other animals in South America absolutely depends on their power of resisting the attacks of insects: so that individuals which could by any means defend themselves from these small enemies, would be able to range into new pastures and thus gain a great advantage. It is not that the larger quadrupeds are actually destroyed (except in some rare cases) by the flies, but they are incessantly harassed and their strength reduced, so that they are more subject to disease, or not so well enabled in a coming dearth to search for food, or to escape from beasts of prey.

Organs now of trifling importance have probably in some cases been of high importance to an early progenitor, and, after having been slowly perfected at a former period, have been transmitted in nearly the same state, although now become of very slight use; and any actually injurious deviations in their structure will always have been checked by natural selection. Seeing how important an organ of locomotion the tail is in most aquatic animals, its general presence and use for many purposes in so many land animals, which in their lungs or modified swim-bladders betray their aquatic origin, may perhaps be thus accounted for. A well-developed tail having been formed in an aquatic animal, it might subsequently come to be worked in for all sorts of purposes, as a fly-flapper, an organ of prehension, or as an aid in turning, as with the dog, though the aid must be slight, for the hare, with hardly any tail, can double quickly enough.

In the second place, we may sometimes attribute importance to characters which are really of very little importance, and which have originated from quite secondary causes, independently of natural selection. We should remember that climate, food, &c., probably have some little direct influence on the organisation; that characters reappear from the law of reversion;, that correlation of growth will have had a most important influence in modifying various structures; and finally, that sexual selection will often have largely modified the external characters of animals having a will, to give one male an advantage in fighting with another or in charming the females. Moreover when a modification of structure has primarily arisen from the above or other unknown causes, it may at first have been of no advantage to the species, but may subsequently have been taken advantage of by the descendants of the species under new conditions of life and with newly acquired habits.

To give a few instances to illustrate these latter remarks. If green woodpeckers alone had existed, and we did not know that there were many black and pied kinds, I dare say that we should have thought that the green colour was a beautiful adaptation to hide this tree-frequenting bird from its enemies; and consequently that it was a character of importance and might have been acquired through natural selection; as it is, I have no doubt that the colour is due to some quite distinct cause, probably to sexual selection. A trailing bamboo in the Malay Archipelago climbs the loftiest trees by the aid of exquisitely constructed hooks clustered around the ends of the branches, and this contrivance, no doubt, is of the highest service to the plant; but as we see nearly similar hooks on many trees which are not climbers the hooks on the bamboo may have arisen from unknown laws of growth, and have been subsequently taken advantage of by the plant undergoing further modification and becoming a climber. The naked skin on the head of a vulture is generally looked at as a direct adaptation for wallowing in putridity; and so it may be, or it may possibly be due to the direct action of putrid matter; but we should be very cautious in drawing any such inference, when we see that the skin on the head of the clean-feeding male turkey is likewise naked. The sutures in the skulls of young mammals have been advanced as a beautiful adaptation for aiding parturition, and no doubt they facilitate, or may be indispensable for this act; but as sutures occur in the skulls of young birds and reptiles, which have only to escape from a broken egg, we may infer that this structure has arisen from the laws of growth, and has been taken advantage of in the parturition of the higher animals.

We are profoundly ignorant of the causes producing slight and unimportant variations; and we are immediately made conscious of this by reflecting on the differences in the breeds of our domesticated animals in different countries, more especially in the less civilized countries where there has been but little artificial selection. Careful observers are convinced that a damp climate affects the growth of the hair, and that with the hair the horns are correlated. Mountain breeds always differ from lowland breeds; and a mountainous country would probably affect the hind limbs from exercising them more, and possibly even the form of the pelvis; and then by the law of homologous variation, the front limbs and even the head would probably be affected. The shape, also, of the pelvis might affect by pressure the shape of the head of the young in the womb. The laborious breathing necessary in high regions would, we have some reason to believe, increase the size of the chest; and again correlation would come into play. Animals kept by savages in different countries often have to struggle for their own subsistence, and would be exposed to a certain extent to natural selection, and individuals with slightly different constitutions would succeed best under different climates; and there is reason to believe that constitution and colour are correlated. A good observer, also, states that in cattle susceptibility to the attacks of flies is correlated with colour, as is the liability to be poisoned by certain plants; so that colour would be thus subjected to the action of natural selection. But we are far too ignorant to speculate on the relative importance of the several known and unknown laws of variation; and I have here alluded to them only to show that, if we are unable to account for the characteristic differences of our domestic breeds, which nevertheless we generally admit to have arisen through ordinary generation, we ought not to lay too much stress on our ignorance of the precise cause of the slight analogous differences between species. I might have adduced for this same purpose the differences between the races of man, which are so strongly marked; I may add that some little light can apparently be thrown on the origin of these differences, chiefly through sexual selection of a particular kind, but without here entering on copious details my reasoning would appear frivolous.

The foregoing remarks lead me to say a few words on the protest lately made by some naturalists, against the utilitarian doctrine that every detail of structure has been produced for the good of its possessor. They believe that very many structures have been created for beauty in the eyes of man, or for mere variety. This doctrine, if true, would be absolutely fatal to my theory. Yet I fully admit that many structures are of no direct use to their possessors. Physical conditions probably have had some little effect on structure, quite independently of any good thus gained. Correlation of growth has no doubt played a most important part, and a useful modification of one part will often have entailed on other parts diversified changes of no direct use. So again characters which formerly were useful, or which formerly had arisen from correlation of growth, or from other unknown cause, may reappear from the law of reversion, though now of no direct use. The effects of sexual selection, when displayed in beauty to charm the females, can be called useful only in rather a forced sense. But by far the most important consideration is that the chief part of the organisation of every being is simply due to inheritance; and consequently, though each being assuredly is well fitted for its place in nature, many structures now have no direct relation to the habits of life of each species. Thus, we can hardly believe that the webbed feet of the upland goose or of the frigate-bird are of special use to these birds; we cannot believe that the same bones in the arm of the monkey, in the fore leg of the horse, in the wing of the bat, and in the flipper of the seal, are of special use to these animals. We may safely attribute these structures to inheritance. But to the progenitor of the upland goose and of the frigate-bird, webbed feet no doubt were as useful as they now are to the most aquatic of existing birds. So we may believe that the progenitor of the seal had not a flipper, but a foot with five toes fitted for walking or grasping; and we may further venture to believe that the several bones in the limbs of the monkey, horse, and bat, which have been inherited from a common progenitor, were formerly of more special use to that progenitor, or its progenitors, than they now are to these animals having such widely diversified habits. Therefore we may infer that these several bones might have been acquired through natural selection, subjected formerly, as now, to the several laws of inheritance, reversion, correlation of growth, &c. Hence every detail of structure in every living creature (making some little allowance for the direct action of physical conditions) may be viewed, either as having been of special use to some ancestral form, or as being now of special use to the descendants of this form either directly, or indirectly through the complex laws of growth.

Natural selection cannot possibly produce any modification in any one species exclusively for the good of another species; though throughout nature one species incessantly takes advantage of, and profits by, the structure of another. But natural selection can and does often produce structures for the direct injury of other species, as we see in the fang of the adder, and in the ovipositor of the ichneumon, by which its eggs are deposited in the living bodies of other insects. If it could be proved that any part of the structure of any one species had been formed for the exclusive good of another species, it would annihilate my theory, for such could not have been produced through natural selection. Although many statements may be found in works on natural history to this effect, I cannot find even one which seems to me of any weight. It is admitted that the rattlesnake has a poison-fang for its own defence and for the destruction of its prey; but some authors suppose that at the same time this snake is furnished with a rattle for its own injury, namely, to warn its prey to escape. I would almost as soon believe that the cat curls the end of its tail when preparing to spring, in order to warn the doomed mouse. But I have not space here to enter on this and other such cases.

Natural selection will never produce in a being anything injurious to itself, for natural selection acts solely by and for the good of each. No organ will be formed, as Paley has remarked, for the purpose of causing pain or for doing an injury to its possessor. If a fair balance be struck between the good and evil caused by each part, each will be found on the whole advantageous. After the lapse of time, under changing conditions of life, if any part comes to be injurious, it will be modified; or if it be not so, the being will become extinct, as myriads have become extinct.

Natural selection tends only to make each organic being as perfect as, or slightly more perfect than, the other inhabitants of the same country with which it has to struggle for existence. And we see that this is the degree of perfection attained under nature. The endemic productions of New Zealand, for instance, are perfect one compared with another; but they are now rapidly yielding before the advancing legions of plants and animals introduced from Europe. Natural selection will not produce absolute perfection, nor do we always meet, as far as we can judge, with this high standard under nature. The correction for the aberration of light is said, on high authority, not to be perfect even in that most perfect organ, the eye. If our reason leads us to admire with enthusiasm a multitude of inimitable contrivances in nature, this same reason tells us, though we may easily err on both sides, that some other contrivances are less perfect. Can we consider the sting of the wasp or of the bee as perfect, which, when used against many attacking animals, cannot be withdrawn, owing to the backward serratures, and so inevitably causes the death of the insect by tearing out its viscera?

If we look at the sting of the bee, as having originally existed in a remote progenitor as a boring and serrated instrument, like that in so many members of the same great order, and which has been modified but not perfected for its present purpose, with the poison originally adapted to cause galls subsequently intensified, we can perhaps understand how it is that the use of the sting should so often cause the insect's own death: for if on the whole the power of stinging be useful to the community, it will fulfil all the requirements of natural selection, though it may cause the death of some few members. If we admire the truly wonderful power of scent by which the males of many insects find their females, can we admire the production for this single purpose of thousands of drones, which are utterly useless to the community for any other end, and which are ultimately slaughtered by their industrious and sterile sisters? It may be difficult, but we ought to admire the savage instinctive hatred of the queen-bee, which urges her instantly to destroy the young queens her daughters as soon as born, or to perish herself in the combat; for undoubtedly this is for the good of the community; and maternal love or maternal hatred, though the latter fortunately is most rare, is all the same to the inexorable principle of natural selection. If we admire the several ingenious contrivances, by which the flowers of the orchis and of many other plants are fertilised through insect agency, can we consider as equally perfect the elaboration by our fir-trees of dense clouds of pollen, in order that a few granules may be wafted by a chance breeze on to the ovules?

Summary of Chapter. We have in this chapter discussed some of the difficulties and objections which may be urged against my theory. Many of them are very grave; but I think that in the discussion light has been thrown on several facts, which on the theory of independent acts of creation are utterly obscure. We have seen that species at any one period are not indefinitely variable, and are not linked together by a multitude of intermediate gradations, partly because the process of natural selection will always be very slow, and will act, at any one time, only on a very few forms; and partly because the very process of natural selection almost implies the continual supplanting and extinction of preceding and intermediate gradations. Closely allied species, now living on a continuous area, must often have been formed when the area was not continuous, and when the conditions of life did not insensibly graduate away from one part to another. When two varieties are formed in two districts of a continuous area, an intermediate variety will often be formed, fitted for an intermediate zone; but from reasons assigned, the intermediate variety will usually exist in lesser numbers than the two forms which it connects; consequently the two latter, during the course of further modification, from existing in greater numbers, will have a great advantage over the less numerous intermediate variety, and will thus generally succeed in supplanting and exterminating it.

We have seen in this chapter how cautious we should be in concluding that the most different habits of life could not graduate into each other; that a bat, for instance, could not have been formed by natural selection from an animal which at first could only glide through the air.

We have seen that a species may under new conditions of life change its habits, or have diversified habits, with some habits very unlike those of its nearest congeners. Hence we can understand bearing in mind that each organic being is trying to live wherever it can live, how it has arisen that there are upland geese with webbed feet, ground woodpeckers, diving thrushes, and petrels with the habits of auks.

Although the belief that an organ so perfect as the eye could have been formed by natural selection, is more than enough to stagger any one; yet in the case of any organ, if we know of a long series of gradations in complexity, each good for its possessor, then, under changing conditions of life, there is no logical impossibility in the acquirement of any conceivable degree of perfection through natural selection. In the cases in which we know of no intermediate or transitional states, we should be very cautious in concluding that none could have existed, for the homologies of many organs and their intermediate states show that wonderful metamorphoses in function are at least possible. For instance, a swim-bladder has apparently been converted into an air-breathing lung. The same organ having performed simultaneously very different functions, and then having been specialised for one function; and two very distinct organs having performed at the same time the same function, the one having been perfected whilst aided by the other, must often have largely facilitated transitions.

We are far too ignorant, in almost every case, to be enabled to assert that any part or organ is so unimportant for the welfare of a species, that modifications in its structure could not have been slowly accumulated by means of natural selection. But we may confidently believe that many modifications, wholly due to the laws of growth, and at first in no way advantageous to a species, have been subsequently taken advantage of by the still further modified descendants of this species. We may, also, believe that a part formerly of high importance has often been retained (as the tail of an aquatic animal by its terrestrial descendants), though it has become of such small importance that it could not, in its present state, have been acquired by natural selection, a power which acts solely by the preservation of profitable variations in the struggle for life.

Natural selection will produce nothing in one species for the exclusive good or injury of another; though it may well produce parts, organs, and excretions highly useful or even indispensable, or highly injurious to another species, but in all cases at the same time useful to the owner. Natural selection in each well-stocked country, must act chiefly through the competition of the inhabitants one with another, and consequently will produce perfection, or strength in the battle for life, only according to the standard of that country. Hence the inhabitants of one country, generally the smaller one, will often yield, as we see they do yield, to the inhabitants of another and generally larger country. For in the larger country there will have existed more individuals, and more diversified forms, and the competition will have been severer, and thus the standard of perfection will have been rendered higher. Natural selection will not necessarily produce absolute perfection; nor, as far as we can judge by our limited faculties, can absolute perfection be everywhere found.

On the theory of natural selection we can clearly understand the full meaning of that old canon in natural history, 'Natura non facit saltum.' This canon, if we look only to the present inhabitants of the world, is not strictly correct, but if we include all those of past times, it must by my theory be strictly true.

It is generally acknowledged that all organic beings have been formed on two great laws Unity of Type, and the Conditions of Existence. By unity of type is meant that fundamental agreement in structure, which we see in organic beings of the same class, and which is quite independent of their habits of life. On my theory, unity of type is explained by unity of descent. The expression of conditions of existence, so often insisted on by the illustrious Cuvier, is fully embraced by the principle of natural selection. For natural selection acts by either now adapting the varying parts of each being to its organic and inorganic conditions of life; or by having adapted them during long-past periods of time: the adaptations being aided in some cases by use and disuse, being slightly affected by the direct action of the external conditions of life, and being in all cases subjected to the several laws of growth. Hence, in fact, the law of the Conditions of Existence is the higher law; as it includes, through the inheritance of former adaptations, that of Unity of Type. 
THE subject of instinct might have been worked into the previous chapters; but I have thought that it would be more convenient to treat the subject separately, especially as so wonderful an instinct as that of the hive-bee making its cells will probably have occurred to many readers, as a difficulty sufficient to overthrow my whole theory. I must premise, that I have nothing to do with the origin of the primary mental powers, any more than I have with that of life itself. We are concerned only with the diversities of instinct and of the other mental qualities of animals within the same class.

I will not attempt any definition of instinct. It would be easy to show that several distinct mental actions are commonly embraced by this term; but every one understands what is meant, when it is said that instinct impels the cuckoo to migrate and to lay her eggs in other birds' nests. An action, which we ourselves should require experience to enable us to perform, when performed by an animal, more especially by a very young one, without any experience, and when performed by many individuals in the same way, without their knowing for what purpose it is performed, is usually said to be instinctive. But I could show that none of these characters of instinct are universal. A little dose, as Pierre Huber expresses it, of judgment or reason, often comes into play, even in animals very low in the scale of nature.

Frederick Cuvier and several of the older metaphysicians have compared instinct with habit. This comparison gives, I think, a remarkably accurate notion of the frame of mind under which an instinctive action is performed, but not of its origin. How unconsciously many habitual actions are performed, indeed not rarely in direct opposition to our conscious will! yet they may be modified by the will or reason. Habits easily become associated with other habits, and with certain periods of time and states of the body. When once acquired, they often remain constant throughout life. Several other points of resemblance between instincts and habits could be pointed out. As in repeating a well-known song, so in instincts, one action follows another by a sort of rhythm; if a person be interrupted in a song, or in repeating anything by rote, he is generally forced to go back to recover the habitual train of thought: so P. Huber found it was with a caterpillar, which makes a very complicated hammock; for if he took a caterpillar which had completed its hammock up to, say, the sixth stage of construction, and put it into a hammock completed up only to the third stage, the caterpillar simply re-performed the fourth, fifth, and sixth stages of construction. If, however, a caterpillar were taken out of a hammock made up, for instance, to the third stage, and were put into one finished up to the sixth stage, so that much of its work was already done for it, far from feeling the benefit of this, it was much embarrassed, and, in order to complete its hammock, seemed forced to start from the third stage, where it had left off, and thus tried to complete the already finished work.

If we suppose any habitual action to become inherited and I think it can be shown that this does sometimes happen then the resemblance between what originally was a habit and an instinct becomes so close as not to be distinguished. If Mozart, instead of playing the pianoforte at three years old with wonderfully little practice, had played a tune with no practice at all, be might truly be said to have done so instinctively. But it would be the most serious error to suppose that the greater number of instincts have been acquired by habit in one generation, and then transmitted by inheritance to succeeding generations. It can be clearly shown that the most wonderful instincts with which we are acquainted, namely, those of the hive-bee and of many ants, could not possibly have been thus acquired.

It will be universally admitted that instincts are as important as corporeal structure for the welfare of each species, under its present conditions of life. Under changed conditions of life, it is at least possible that slight modifications of instinct might be profitable to a species; and if it can be shown that instincts do vary ever so little, then I can see no difficulty in natural selection preserving and continually accumulating variations of instinct to any extent that may be profitable. It is thus, as I believe, that all the most complex and wonderful instincts have originated. As modifications of corporeal structure arise from, and are increased by, use or habit, and are diminished or lost by disuse, so I do not doubt it has been with instincts. But I believe that the effects of habit are of quite subordinate importance to the effects of the natural selection of what may be called accidental variations of instincts; that is of variations produced by the same unknown causes which produce slight deviations of bodily structure.

No complex instinct can possibly be produced through natural selection, except by the slow and gradual accumulation of numerous, slight, yet profitable, variations. Hence, as in the case of corporeal structures, we ought to find in nature, not the actual transitional gradations by which each complex instinct has been acquired for these could be found only in the lineal ancestors of each species but we ought to find in the collateral lines of descent some evidence of such gradations; or we ought at least to be able to show that gradations of some kind are possible; and this we certainly can do. I have been surprised to find, making allowance for the instincts of animals having been but little observed except in Europe and North America, and for no instinct being known amongst extinct species, how very generally gradations, leading to the most complex instincts, can be discovered. The canon of 'Natura non facit saltum' applies with almost equal force to instincts as to bodily organs. Changes of instinct may sometimes be facilitated by the same species having different instincts at different periods of life, or at different seasons of the year, or when placed under different circumstances, &c.; in which case either one or the other instinct might be preserved by natural selection. And such instances of diversity of instinct in the same species can be shown to occur in nature.

Again as in the case of corporeal structure, and conformably with my theory, the instinct of each species is good for itself, but has never, as far as we can judge, been produced for the exclusive good of others. One of the strongest instances of an animal apparently performing an action for the sole good of another, with which I am acquainted, is that of aphides voluntarily yielding their sweet excretion to ants: that they do so voluntarily, the following facts show. I removed all the ants from a group of about a dozen aphides on a dock-plant, and prevented their attendance during several hours. After this interval, I felt sure that the aphides would want to excrete. I watched them for some time through a lens, but not one excreted; I then tickled and stroked them with a hair in the same manner, as well as I could, as the ants do with their antennae; but not one excreted. Afterwards I allowed an ant to visit them, and it immediately seemed, by its eager way of running about, to be well aware what a rich flock it had discovered; it then began to play with its antennae on the abdomen first of one aphis and then of another; and each aphis, as soon as it felt the antennae, immediately lifted up its abdomen and excreted a limpid drop of sweet juice, which was eagerly devoured by the ant. Even the quite young aphides behaved in this manner, showing that the action was instinctive, and not the result of experience. But as the excretion is extremely viscid, it is probably a convenience to the aphides to have it removed; and therefore probably the aphides do not instinctively excrete for the sole good of the ants. Although I do not believe that any animal in the world performs an action for the exclusive good of another of a distinct species, yet each species tries to take advantage of the instincts of others, as each takes advantage of the weaker bodily structure of others. So again, in some few cases, certain instincts cannot be considered as absolutely perfect; but as details on this and other such points are not indispensable, they may be here passed over.

As some degree of variation in instincts under a state of nature, and the inheritance of such variations, are indispensable for the action of natural selection, as many instances as possible ought to have been here given; but want of space prevents me. I can only assert, that instincts certainly do vary for instance, the migratory instinct, both in extent and direction, and in its total loss. So it is with the nests of birds, which vary partly in dependence on the situations chosen, and on the nature and temperature of the country inhabited, but often from causes wholly unknown to us: Audubon has given several remarkable cases of differences in nests of the same species in the northern and southern United States. Fear of any particular enemy is certainly an instinctive quality, as may be seen in nestling birds, though it is strengthened by experience, and by the sight of fear of the same enemy in other animals. But fear of man is slowly acquired, as I have elsewhere shown, by various animals inhabiting desert islands; and we may see an instance of this, even in England, in the greater wildness of all our large birds than of our small birds; for the large birds have been most persecuted by man. We may safely attribute the greater wildness of our large birds to this cause; for in uninhabited islands large birds are not more fearful than small; and the magpie, so wary in England, is tame in Norway, as is the hooded crow in Egypt.

That the general disposition of individuals of the same species, born in a state of nature, is extremely diversified, can be shown by a multitude of facts. Several cases also, could be given, of occasional and strange habits in certain species, which might, if advantageous to the species, give rise, through natural selection, to quite new instincts. But I am well aware that these general statements, without facts given in detail, can produce but a feeble effect on the reader's mind. I can only repeat my assurance, that I do not speak without good evidence.

The possibility, or even probability, of inherited variations of instinct in a state of nature will be strengthened by briefly considering a few cases under domestication. We shall thus also be enabled to see the respective parts which habit and the selection of so-called accidental variations have played in modifying the mental qualities of our domestic animals. A number of curious and authentic instances could be given of the inheritance of all shades of disposition and tastes, and likewise of the oddest tricks, associated with certain frames of mind or periods of time. But let us look to the familiar case of the several breeds of dogs: it cannot be doubted that young pointers (I have myself seen a striking instance) will sometimes point and even back other dogs the very first time that they are taken out; retrieving is certainly in some degree inherited by retrievers; and a tendency to run round, instead of at, a flock of sheep, by shepherd-dogs. I cannot see that these actions, performed without experience by the young, and in nearly the same manner by each individual, performed with eager delight by each breed, and without the end being known, for the young pointer can no more know that he points to aid his master, than the white butterfly knows why she lays her eggs on the leaf of the cabbage, I cannot see that these actions differ essentially from true instincts. If we were to see one kind of wolf, when young and without any training, as soon as it scented its prey, stand motionless like a statue, and then slowly crawl forward with a peculiar gait; and another kind of wolf rushing round, instead of at, a herd of deer, and driving them to a distant point, we should assuredly call these actions instinctive. Domestic instincts, as they may be called, are certify far less fixed or invariable than natural instincts; but they have been acted on by far less rigorous selection, and have been transmitted for an incomparably shorter period, under less fixed conditions of life.

How strongly these domestic instincts, habits, and dispositions are inherited, and how curiously they become mingled, is well shown when different breeds of dogs are crossed. Thus it is known that a cross with a bull-dog has affected for many generations the courage and obstinacy of greyhounds; and a cross with a greyhound has given to a whole family of shepherd-dogs a tendency to hunt hares. These domestic instincts, when thus tested by crossing, resemble natural instincts, which in a like manner become curiously blended together, and for a long period exhibit traces of the instincts of either parent: for example, Le Roy describes a dog, whose great-grandfather was a wolf, and this dog showed a trace of its wild parentage only in one way, by not coming in a straight line to his master when called.

Domestic instincts are sometimes spoken of as actions which have become inherited solely from long-continued and compulsory habit, but this, I think, is not true. No one would ever have thought of teaching, or probably could have taught, the tumbler-pigeon to tumble, an action which, as I have witnessed, is performed by young birds, that have never seen a pigeon tumble. We may believe that some one pigeon showed a slight tendency to this strange habit, and that the long-continued selection of the best individuals in successive generations made tumblers what they now are; and near Glasgow there are house-tumblers, as I hear from Mr Brent, which cannot fly eighteen inches high without going head over heels. It may be doubted whether any one would have thought of training a dog to point, had not some one dog naturally shown a tendency in this line; and this is known occasionally to happen, as I once saw in a pure terrier. When the first tendency was once displayed, methodical selection and the inherited effects of compulsory training in each successive generation would soon complete the work; and unconscious selection is still at work, as each man tries to procure, without intending to improve the breed, dogs which will stand and hunt best. On the other hand, habit alone in some cases has sufficed; no animal is more difficult to tame than the young of the wild rabbit; scarcely any animal is tamer than the young of the tame rabbit; but I do not suppose that domestic rabbits have ever been selected for tameness; and I presume that we must attribute the whole of the inherited change from extreme wildness to extreme tameness, simply to habit and long-continued close confinement.

Natural instincts are lost under domestication: a remarkable instance of this is seen in those breeds of fowls which very rarely or never become 'broody,' that is, never wish to sit on their eggs. Familiarity alone prevents our seeing how universally and largely the minds of our domestic animals have been modified by domestication. It is scarcely possible to doubt that the love of man has become instinctive in the dog. All wolves, foxes, jackals, and species of the cat genus, when kept tame, are most eager to attack poultry, sheep, and pigs; and this tendency has been found incurable in dogs which have been brought home as puppies from countries, such as Tierra del Fuego and Australia, where the savages do not keep these domestic animals. How rarely, on the other hand, do our civilised dogs, even when quite young, require to be taught not to attack poultry, sheep, and pigs! No doubt they occasionally do make an attack, and are then beaten; and if not cured, they are destroyed; so that habit, with some degree of selection, has probably concurred in civilising by inheritance our dogs. On the other hand, young chickens have lost, wholly by habit, that fear of the dog and cat which no doubt was originally instinctive in them, in the same way as it is so plainly instinctive in young pheasants, though reared under a hen. It is not that chickens have lost all fear, but fear only of dogs and cats, for if the hen gives the danger-chuckle, they will run (more especially young turkeys) from under her, and conceal themselves in the surrounding grass or thickets; and this is evidently done for the instinctive purpose of allowing, as we see in wild ground-birds, their mother to fly away. But this instinct retained by our chickens has become useless under domestication, for the mother-hen has almost lost by disuse the power of flight.

Hence, we may conclude, that domestic instincts have been acquired and natural instincts have been lost partly by habit, and partly by man selecting and accumulating during successive generations, peculiar mental habits and actions, which at first appeared from what we must in our ignorance call an accident. In some cases compulsory habit alone has sufficed to produce such inherited mental changes; in other cases compulsory habit has done nothing, and all has been the result of selection, pursued both methodically and unconsciously; but in most cases, probably, habit and selection have acted together.

We shall, perhaps, best understand how instincts in a state of nature have become modified by selection, by considering a few cases. I will select only three, out of the several which I shall have to discuss in my future work, namely, the instinct which leads the cuckoo to lay her eggs in other birds' nests; the slave-making instinct of certain ants; and the comb-making power of the hive-bee: these two latter instincts have generally, and most justly, been ranked by naturalists as the most wonderful of all known instincts.

It is now commonly admitted that the more immediate and final cause of the cuckoo's instinct is, that she lays her eggs, not daily, but at intervals of two or three days; so that, if she were to make her own nest and sit on her own eggs, those first laid would have to be left for some time unincubated, or there would be eggs and young birds of different ages in the same nest. If this were the case, the process of laying and hatching might be inconveniently long, more especially as she has to migrate at a very early period; and the first hatched young would probably have to be fed by the male alone. But the American cuckoo is in this predicament; for she makes her own nest and has eggs and young successively hatched, all at the same time. It has been asserted that the American cuckoo occasionally lays her eggs in other birds' nests; but I hear on the high authority of Dr. Brewer, that this is a mistake. Nevertheless, I could give several instances of various birds which have been known occasionally to lay their eggs in other birds' nests. Now let us suppose that the ancient progenitor of our European cuckoo had the habits of the American cuckoo; but that occasionally she laid an egg in another bird's nest. If the old bird profited by this occasional habit, or if the young were made more vigorous by advantage having been taken of the mistaken maternal instinct of another bird, than by their own mother's care, encumbered as she can hardly fail to be by having eggs and young of different ages at the same time; then the old birds or the fostered young would gain an advantage. And analogy would lead me to believe, that the young thus reared would be apt to follow by inheritance the occasional and aberrant habit of their mother, and in their turn would be apt to lay their eggs in other birds' nests, and thus be successful in rearing their young. By a continued process of this nature, I believe that the strange instinct of our cuckoo could be, and has been, generated. I may add that, according to Dr. Gray and to some other observers, the European cuckoo has not utterly lost all maternal love and care for her own offspring.

The occasional habit of birds laying their eggs in other birds' nests, either of the same or of a distinct species, is not very uncommon with the Gallinaceae; and this perhaps explains the origin of a singular instinct in the allied group of ostriches. For several hen ostriches, at least in the case of the American species, unite and lay first a few eggs in one nest and then in another; and these are hatched by the males. This instinct may probably be accounted for by the fact of the hens laying a large number of eggs; but, as in the case of the cuckoo, at intervals of two or three days. This instinct, however, of the American ostrich has not as yet been perfected; for a surprising number of eggs lie strewed over the plains, so that in one day's hunting I picked up no less than twenty lost and wasted eggs.

Many bees are parasitic, and always lay their eggs in the nests of bees of other kinds. This case is more remarkable than that of the cuckoo; for these bees have not only their instincts but their structure modified in accordance with their parasitic habits; for they do not possess the pollen-collecting apparatus which would be necessary if they had to store food for their own young. Some species, likewise, of Sphegidae (wasp-like insects) are parasitic on other species; and M. Fabre has lately shown good reason for believing that although the Tachytes nigra generally makes its own burrow and stores it with paralysed prey for its own larvae to feed on, yet that when this insect finds a burrow already made and stored by another sphex, it takes advantage of the prize, and becomes for the occasion parasitic. In this case, as with the supposed case of the cuckoo, I can see no difficulty in natural selection making an occasional habit permanent, if of advantage to the species, and if the insect whose nest and stored food are thus feloniously appropriated, be not thus exterminated.

Slave-making instinct. This remarkable instinct was first discovered in the Formica (Polyerges) rufescens by Pierre Huber, a better observer even than his celebrated father. This ant is absolutely dependent on its slaves; without their aid, the species would certainly become extinct in a single year. The males and fertile females do no work. The workers or sterile females, though most energetic and courageous in capturing slaves, do no other work. They are incapable of making their own nests, or of feeding their own larvae. When the old nest is found inconvenient, and they have to migrate, it is the slaves which determine the migration, and actually carry their masters in their jaws. So utterly helpless are the masters, that when Huber shut up thirty of them without a slave, but with plenty of the food which they like best, and with their larvae and pupae to stimulate them to work, they did nothing; they could not even feed themselves, and many perished of hunger. Huber then introduced a single slave (F. fusca), and she instantly set to work, fed and saved the survivors; made some cells and tended the larvae, and put all to rights. What can be more extraordinary than these well-ascertained facts? If we had not known of any other slave-making ant, it would have been hopeless to have speculated how so wonderful an instinct could have been perfected.

Formica sanguinea was likewise first discovered by P. Huber to be a slave-making ant. This species is found in the southern parts of England, and its habits have been attended to by Mr. F. Smith, of the British Museum, to whom I am much indebted for information on this and other subjects. Although fully trusting to the statements of Huber and Mr. Smith, I tried to approach the subject in a sceptical frame of mind, as any one may well be excused for doubting the truth of so extraordinary and odious an instinct as that of making slaves. Hence I will give the observations which I have made myself made, in some little detail. I opened fourteen nests of F. sanguinea, and found a few slaves in all. Males and fertile females of the slave-species are found only in their own proper communities, and have never been observed in the nests of F. sanguinea. The slaves are black and not above half the size of their red masters, so that the contrast in their appearance is very great. When the nest is slightly disturbed, the slaves occasionally come out, and like their masters are much agitated and defend their nest: when the nest is much disturbed and the larvae and pupae are exposed, the slaves work energetically with their masters in carrying them away to a place of safety. Hence, it is clear, that the slaves feel quite at home. During the months of June and July, on three successive years, I have watched for many hours several nests in Surrey and Sussex, and never saw a slave either leave or enter a nest. As, during these months, the slaves are very few in number, I thought that they might behave differently when more numerous; but Mr. Smith informs me that he has watched the nests at various hours during May, June and August, both in Surrey and Hampshire, and has never seen the slaves, though present in large numbers in August, either leave or enter the nest. Hence he considers them as strictly household slaves. The masters, on the other hand, may be constantly seen bringing in materials for the nest, and food of all kinds. During the present year, however, in the month of July, I came across a community with an unusually large stock of slaves, and I observed a few slaves mingled with their masters leaving the nest, and marching along the same road to a tall Scotch-fir-tree, twenty-five yards distant, which they ascended together, probably in search of aphides or cocci. According to Huber, who had ample opportunities for observation, in Switzerland the slaves habitually work with their masters in making the nest, and they alone open and close the doors in the morning and evening; and, as Huber expressly states, their principal office is to search for aphides. This difference in the usual habits of the masters and slaves in the two countries, probably depends merely on the slaves being captured in greater numbers in Switzerland than in England.

One day I fortunately chanced to witness a migration from one nest to another, and it was a most interesting spectacle to behold the masters carefully carrying, as Huber has described, their slaves in their jaws. Another day my attention was struck by about a score of the slave-makers haunting the same spot, and evidently not in search of food; they approached and were vigorously repulsed by an independent community of the slave species (F. fusca); sometimes as many as three of these ants clinging to the legs of the slave-making F. sanguinea. The latter ruthlessly killed their small opponents, and carried their dead bodies as food to their nest, twenty-nine yards distant; but they were prevented from getting any pupae to rear as slaves. I then dug up a small parcel of the pupae of F. fusca from another nest, and put them down on a bare spot near the place of combat; they were eagerly seized, and carried off by the tyrants, who perhaps fancied that, after all, they had been victorious in their late combat.

At the same time I laid on the same place a small parcel of the pupae of another species, F. flava, with a few of these little yellow ants still clinging to the fragments of the nest. This species is sometimes, though rarely, made into slaves, as has been described by Mr Smith. Although so small a species, it is very courageous, and I have seen it ferociously attack other ants. In one instance I found to my surprise an independent community of F. flava under a stone beneath a nest of the slave-making F. sanguinea; and when I had accidentally disturbed both nests, the little ants attacked their big neighbours with surprising courage. Now I was curious to ascertain whether F. sanguinea could distinguish the pupae of F. fusca, which they habitually make into slaves, from those of the little and furious F. flava, which they rarely capture, and it was evident that they did at once distinguish them: for we have seen that they eagerly and instantly seized the pupae of F. fusca, whereas they were much terrified when they came across the pupae, or even the earth from the nest of F. flava, and quickly ran away; but in about a quarter of an hour, shortly after all the little yellow ants had crawled away, they took heart and carried off the pupae.

One evening I visited another community of F. sanguinea, and found a number of these ants entering their nest, carrying the dead bodies of F. fusca (showing that it was not a migration) and numerous pupae. I traced the returning file burthened with booty, for about forty yards, to a very thick clump of heath. whence I saw the last individual of F. sanguinea emerge, carrying a pupa; but I was not able to find the desolated nest in the thick heath. The nest, however, must have been close at hand, for two or three individuals of F. fusca were rushing about in the greatest agitation, and one was perched motionless with its own pupa in its mouth on the top of a spray of heath over its ravaged home.

Such are the facts, though they did not need confirmation by me, in regard to the wonderful instinct of making slaves. Let it be observed what a contrast the instinctive habits of F. sanguinea present with those of the F. rufescens. The latter does not build its own nest, does not determine its own migrations, does not collect food for itself or its young, and cannot even feed itself: it is absolutely dependent on its numerous slaves. Formica sanguinea, on the other hand, possesses much fewer slaves, and in the early part of the summer extremely few. The masters determine when and where a new nest shall be formed, and when they migrate, the masters carry the slaves. Both in Switzerland and England the slaves seem to have the exclusive care of the larvae, and the masters alone go on slave-making expeditions. In Switzerland the slaves and masters work together, making and bringing materials for the nest: both, but chiefly the slaves, tend, and milk as it may be called, their aphides; and thus both collect food for the community. In England the masters alone usually leave the nest to collect building materials and food for themselves, their slaves and larvae. So that the masters in this country receive much less service from their slaves than they do in Switzerland.

By what steps the instinct of F. sanguinea originated I will not pretend to conjecture. But as ants, which are not slave-makers, will, as I have seen, carry off pupae of other species, if scattered near their nests, it is possible that pupae originally stored as food might become developed; and the ants thus unintentionally reared would then follow their proper instincts, and do what work they could. If their presence proved useful to the species which had seized them if it were more advantageous to this species to capture workers than to procreate them the habit of collecting pupae originally for food might by natural selection be strengthened and rendered permanent for the very different purpose of raising slaves. When the instinct was once acquired, if carried out to a much less extent even than in our British F. sanguinea, which, as we have seen, is less aided by its slaves than the same species in Switzerland, I can see no difficulty in natural selection increasing and modifying the instinct always supposing each modification to be of use to the species until an ant was formed as abjectly dependent on its slaves as is the Formica rufescens.

Cell-making instinct of the Hive-Bee. I will not here enter on minute details on this subject, but will merely give an outline of the conclusions at which I have arrived. He must be a dull man who can examine the exquisite structure of a comb, so beautifully adapted to its end, without enthusiastic admiration. We hear from mathematicians that bees have practically solved a recondite problem, and have made their cells of the proper shape to hold the greatest possible amount of honey, with the least possible consumption of previous wax in their construction. It has been remarked that a skilful workman, with fitting tools and measures, would find it very difficult to make cells of wax of the true form, though this is perfectly effected by a crowd of bees working in a dark hive. Grant whatever instincts you please, and it seems at first quite inconceivable how they can make all the necessary angles and planes, or even perceive when they are correctly made. But the difficulty is not nearly so great as it at first appears: all this beautiful work can be shown, I think, to follow from a few very simple instincts.

I was led to investigate this subject by Mr. Waterhouse, who has shown that the form of the cell stands in close relation to the presence of adjoining cells; and the following view may, perhaps, be considered only as a modification of this theory. Let us look to the great principle of gradation, and see whether Nature does not reveal to us her method of work. At one end of a short series we have humble-bees, which use their old cocoons to hold honey, sometimes adding to them short tubes of wax, and likewise making separate and very irregular rounded cells of wax. At the other end of the series we have the cells of the hive-bee, placed in a double layer: each cell, as is well know, is an hexagonal prism, with the basal edges of its six sides bevelled so as to join on to a pyramid, formed of three rhombs. These rhombs have certain angles, and the three which form the pyramidal base of a single cell on one side of the comb, enter into the composition of the bases of three adjoining cells on the opposite side. In the series between the extreme perfection of the cells of the hive-bee and the simplicity of those of the humble-bee, we have the cells of the Mexican Melipona domestica, carefully described and figured by Pierre Huber. The Melipona itself is intermediate in structure between the hive and humble bee, but more nearly related to the latter: it forms a nearly regular waxen comb of cylindrical cells, in which the young are hatched, and, in addition, some large cells of wax for holding honey. These latter cells are nearly spherical and of nearly equal sizes, and are aggregated into an irregular mass. But the important point to notice, is that these cells are always made at that degree of nearness to each other, that they would have intersected or broken into each other, if the spheres had been completed; but this is never permitted, the bees building perfectly flat walls of wax between the spheres which thus tend to intersect. Hence each cell consists of an outer spherical portion and of two, three, or more perfectly flat surfaces, according as the cell adjoins two, three or more other cells. When one cell comes into contact with three other cells, which, from the spheres being nearly of the same size, is very frequently and necessarily the case, the three flat surfaces are united into a pyramid; and this pyramid, as Huber has remarked, is manifestly a gross imitation of the three-sided pyramidal basis of the cell of the hive-bee. As in the cells of the hive-bee, so here, the three plane surfaces in any one cell necessarily enter into the construction of three adjoining cells. It is obvious that the Melipona saves wax by this manner of building; for the flat walls between the adjoining cells are not double, but are of the same thickness as the outer spherical portions, and yet each flat portion forms a part of two cells.

Reflecting on this case, it occurred to me that if the Melipona had made its spheres at some given distance from each other, and had made them of equal sizes and had arranged them symmetrically in a double layer, the resulting structure would probably have been as perfect as the comb of the hive-bee. Accordingly I wrote to Professor Miller, of Cambridge, and this geometer has kindly read over the following statement, drawn up from his information, and tells me that it is strictly correct:-

If a number of equal spheres be described with their centres placed in two parallel layers; with the centre of each sphere at the distance of radius X /sqrt[2] or radius X 1.41421 (or at some lesser distance), from the centres of the six surrounding spheres in the same layer; and at the same distance from the centres of the adjoining spheres in the other and parallel layer; then, if planes of intersection between the several spheres in both layers be formed, there will result a double layer of hexagonal prisms united together by pyramidal bases formed of three rhombs; and the rhombs and the sides of the hexagonal prisms will have every angle identically the same with the best measurements which have been made of the cells of the hive-bee.

Hence we may safely conclude that if we could slightly modify the instincts already possessed by the Melipona, and in themselves not very wonderful, this bee would make a structure as wonderfully perfect as that of the hive-bee. We must suppose the Melipona to make her cells truly spherical, and of equal sizes; and this would not be very surprising, seeing that she already does so to a certain extent, and seeing what perfectly cylindrical burrows in wood many insects can make, apparently by turning round on a fixed point. We must suppose the Melipona to arrange her cells in level layers, as she already does her cylindrical cells; and we must further suppose, and this is the greatest difficulty, that she can somehow judge accurately at what distance to stand from her fellow-labourers when several are making their spheres; but she is already so far enabled to judge of distance, that she always describes her spheres so as to intersect largely; and then she unites the points of intersection by perfectly flat surfaces. We have further to suppose, but this is no difficulty, that after hexagonal prisms have been formed by the intersection of adjoining spheres in the same layer, she can prolong the hexagon to any length requisite to hold the stock of honey; in the same way as the rude humble-bee adds cylinders of wax to the circular mouths of her old cocoons. By such modifications of instincts in themselves not very wonderful, hardly more wonderful than those which guide a bird to make its nest, I believe that the hive-bee has acquired, through natural selection, her inimitable architectural powers.

But this theory can be tested by experiment. Following the example of Mr Tegetmeier, I separated two combs, and put between them a long, thick, square strip of wax: the bees instantly began to excavate minute circular pits in it; and as they deepened these little pits, they made them wider and wider until they were converted into shallow basins, appearing to the eye perfectly true or parts of a sphere, and of about the diameter of a cell. It was most interesting to me to observe that wherever several bees had begun to excavate these basins near together, they had begun their work at such a distance from each other, that by the time the basins had acquired the above stated width (i.e. about the width of an ordinary cell), and were in depth about one sixth of the diameter of the sphere of which they formed a part, the rims of the basins intersected or broke into each other. As soon as this occurred, the bees ceased to excavate, and began to build up flat walls of wax on the lines of intersection between the basins, so that each hexagonal prism was built upon the festooned edge of a smooth basin, instead of on the straight edges of a three-sided pyramid as in the case of ordinary cells.

I then put into the hive, instead of a thick, square piece of wax, a thin and narrow, knife-edged ridge, coloured with vermilion. The bees instantly began on both sides to excavate little basins near to each other, in the same way as before; but the ridge of wax was so thin, that the bottoms of the basins, if they had been excavated to the same depth as in the former experiment, would have broken into each other from the opposite sides. The bees, however, did not suffer this to happen, and they stopped their excavations in due time; so that the basins, as soon as they had been a little deepened, came to have flat bottoms; and these flat bottoms, formed by thin little plates of the vermilion wax having been left ungnawed, were situated, as far as the eye could judge, exactly along the planes of imaginary intersection between the basins on the opposite sides of the ridge of wax. In parts, only little bits, in other parts, large portions of a rhombic plate had been left between the opposed basins, but the work, from the unnatural state of things, had not been neatly performed. The bees must have worked at very nearly the same rate on the opposite side of the ridge of vermilion wax, as they circularly gnawed away and deepened the basins on both sides, in order to have succeeded in thus leaving flat plates between the basins, by stopping work along the intermediate planes or planes of intersection.

Considering how flexible thin wax is, I do not see that there is any difficulty in the bees, whilst at work on the two sides of a strip of wax, perceiving when they have gnawed the wax away to the proper thinness, and then stopping their work. In ordinary combs it has appeared to me that the bees do not always succeed in working at exactly the same rate from the opposite sides; for I have noticed half-completed rhombs at the base of a just-commenced cell, which were slightly concave on one side, where I suppose that the bees had excavated too quickly, and convex on the opposed side, where the bees had worked less quickly. In one well-marked instance, I put the comb back into the hive and allowed the bees to go on working for a short time and again examined the cell, and I found that the rhombic plate had been completed, and had become perfectly flat: it was absolutely impossible, from the extreme thinness of the little rhombic plate, that they could have affected this by gnawing away the convex side; and I suspect that the bees in such cases stand in the opposed cells and push and bend the ductile and warm wax (which as I have tried is easily done) into its proper intermediate plane, and thus flatten it.

From the experiment of the ridge of vermilion wax, we can clearly see that if the bees were to build for themselves a thin wall of wax, they could make their cells of the proper shape, by standing at the proper distance from each other, by excavating at the same rate, and by endeavouring to make equal spherical hollows, but never allowing the spheres to break into each other. Now bees, as may be clearly seen by examining the edge of a growing comb, do make a rough, circumferential wall or rim all round the comb; and they gnaw into this from the opposite sides, always working circularly as they deepen each cell. They do not make the whole three-sided pyramidal base of any one cell at the same time, but only the one rhombic plate which stands on the extreme growing margin, or the two plates, as the case may be; and they never complete the upper edges of the rhombic plates, until the hexagonal walls are commenced. Some of these statements differ from those made by the justly celebrated elder Huber, but I am convinced of their accuracy; and if I had space, I could show that they are conformable with my theory.

Huber's statement that the very first cell is excavated out of a little parallel-sided wall of wax, is not, as far as I have seen, strictly correct; the first commencement having always been a little hood of wax; but I will not here enter on these details. We see how important a part excavation plays in the construction of the cells; but it would be a great error to suppose that the bees cannot build up a rough wall of wax in the proper position that is, along the plane of intersection between two adjoining spheres. I have several specimens showing clearly that they can do this. Even in the rude circumferential rim or wall of wax round a growing comb, flexures may sometimes be observed, corresponding in position to the planes of the rhombic basal plates of future cells. But the rough wall of wax has in every case to be finished off, by being largely gnawed away on both sides. The manner in which the bees build is curious; they always make the first rough wall from ten to twenty times thicker than the excessively thin finished wall of the cell, which will ultimately be left. We shall understand how they work, by supposing masons first to pile up a broad ridge of cement, and then to begin cutting it away equally on both sides near the ground, till a smooth, very thin wall is left in the middle; the masons always piling up the cut-away cement, and adding fresh cement, on the summit of the ridge. We shall thus have a thin wall steadily growing upward; but always crowned by a gigantic coping. From all the cells, both those just commenced and those completed, being thus crowned by a strong coping of wax, the bees can cluster and crawl over the comb without injuring the delicate hexagonal walls, which are only about one four-hundredth of an inch in thickness; the plates of the pyramidal basis being about twice as thick. By this singular manner of building, strength is continually given to the comb, with the utmost ultimate economy of wax.

It seems at first to add to the difficulty of understanding how the cells are made, that a multitude of bees all work together; one bee after working a short time at one cell going to another, so that, as Huber has stated, a score of individuals work even at the commencement of the first cell. I was able practically to show this fact, by covering the edges of the hexagonal walls of a single cell, or the extreme margin of the circumferential rim of a growing comb, with an extremely thin layer of melted vermilion wax; and I invariably found that the colour was most delicately diffused by the bees as delicately as a painter could have done with his brush by atoms of the coloured wax having been taken from the spot on which it had been placed, and worked into the growing edges of the cells all round. The work of construction seems to be a sort of balance struck between many bees, all instinctively standing at the same relative distance from each other, all trying to sweep equal spheres, and then building up, or leaving ungnawed, the planes of intersection between these spheres. It was really curious to note in cases of difficulty, as when two pieces of comb met at an angle, how often the bees would entirely pull down and rebuild in different ways the same cell, sometimes recurring to a shape which they had at first rejected.

When bees have a place on which they can stand in their proper positions for working, for instance, on a slip of wood, placed directly under the middle of a comb growing downwards so that the comb has to be built over one face of the slip in this case the bees can lay the foundations of one wall of a new hexagon, in its strictly proper place, projecting beyond the other completed cells. It suffices that the bees should be enabled to stand at their proper relative distances from each other and from the walls of the last completed cells, and then, by striking imaginary spheres, they can build up a wall intermediate between two adjoining spheres; but, as far as I have seen, they never gnaw away and finish off the angles of a cell till a large part both of that cell and of the adjoining cells has been built. This capacity in bees of laying down under certain circumstances a rough wall in its proper place between two just-commenced cells, is important, as it bears on a fact, which seems at first quite subversive of the foregoing theory; namely, that the cells on the extreme margin of wasp-combs are sometimes strictly hexagonal; but I have not space here to enter on this subject. Nor does there seem to me any great difficulty in a single insect (as in the case of a queen-wasp) making hexagonal cells, if she work alternately on the inside and outside of two or three cells commenced at the same time, always standing at the proper relative distance from the parts of the cells just begun, sweeping spheres or cylinders, and building up intermediate planes. It is even conceivable that an insect might, by fixing on a point at which to commence a cell, and then moving outside, first to one point, and then to five other points, at the proper relative distances from the central point and from each other, strike the planes of intersection, and so make an isolated hexagon: but I am not aware that any such case has been observed; nor would any good be derived from a single hexagon being built, as in its construction more materials would be required than for a cylinder.

As natural selection acts only by the accumulation of slight modifications of structure or instinct, each profitable to the individual under its conditions of life, it may reasonably be asked, how a long and graduated succession of modified architectural instincts, all tending towards the present perfect plan of construction, could have profited the progenitors of the hive-bee? I think the answer is not difficult: it is known that bees are often hard pressed to get sufficient nectar; and I am informed by Mr. Tegetmeier that it has been experimentally found that no less than from twelve to fifteen pounds of dry sugar are consumed by a hive of bees for the secretion of each pound of wax; so that a prodigious quantity of fluid nectar must be collected and consumed by the bees in a hive for the secretion of the wax necessary for the construction of their combs. Moreover, many bees have to remain idle for many days during the process of secretion. A large store of honey is indispensable to support a large stock of bees during the winter; and the security of the hive is known mainly to depend on a large number of bees being supported. Hence the saving of wax by largely saving honey must be a most important element of success in any family of bees. Of course the success of any species of bee may be dependent on the number of its parasites or other enemies, or on quite distinct causes, and so be altogether independent of the quantity of honey which the bees could collect. But let us suppose that this latter circumstance determined, as it probably often does determine, the numbers of a humble-bee which could exist in a country; and let us further suppose that the community lived throughout the winter, and consequently required a store of honey: there can in this case be no doubt that it would be an advantage to our humble-bee, if a slight modification of her instinct led her to make her waxen cells near together, so as to intersect a little; for a wall in common even to two adjoining cells, would save some little wax. Hence it would continually be more and more advantageous to our humble-bee, if she were to make her cells more and more regular, nearer together, and aggregated into a mass, like the cells of the Melipona; for in this case a large part of the bounding surface of each cell would serve to bound other cells, and much wax would be saved. Again, from the same cause, it would be advantageous to the Melipona, if she were to make her cells closer together, and more regular in every way than at present; for then, as we have seen, the spherical surfaces would wholly disappear, and would all be replaced by plane surfaces; and the Melipona would make a comb as perfect as that of the hive-bee. Beyond this stage of perfection in architecture, natural selection could not lead; for the comb of the hive-bee, as far as we can see, is absolutely perfect in economising wax.

Thus, as I believe, the most wonderful of all known instincts, that of the hive-bee, can be explained by natural selection having taken advantage of numerous, successive, slight modifications of simpler instincts; natural selection having by slow degrees, more and more perfectly, led the bees to sweep equal spheres at a given distance from each other in a double layer, and to build up and excavate the wax along the planes of intersection. The bees, of course, no more knowing that they swept their spheres at one particular distance from each other, than they know what are the several angles of the hexagonal prisms and of the basal rhombic plates. The motive power of the process of natural selection having been economy of wax; that individual swarm which wasted least honey in the secretion of wax, having succeeded best, and having transmitted by inheritance its newly acquired economical instinct to new swarms, which in their turn will have had the best chance of succeeding in the struggle for existence.

No doubt many instincts of very difficult explanation could be opposed to the theory of natural selection, cases, in which we cannot see how an instinct could possibly have originated; cases, in which no intermediate gradations are known to exist; cases of instinct of apparently such trifling importance, that they could hardly have been acted on by natural selection; cases of instincts almost identically the same in animals so remote in the scale of nature, that we cannot account for their similarity by inheritance from a common parent, and must therefore believe that they have been acquired by independent acts of natural selection. I will not here enter on these several cases, but will confine myself to one special difficulty, which at first appeared to me insuperable, and actually fatal to my whole theory. I allude to the neuters or sterile females in insect-communities: for these neuters often differ widely in instinct and in structure from both the males and fertile females, and yet, from being sterile, they cannot propagate their kind.

The subject well deserves to be discussed at great length, but I will here take only a single case, that of working or sterile ants. How the workers have been rendered sterile is a difficulty; but not much greater than that of any other striking modification of structure; for it can be shown that some insects and other articulate animals in a state of nature occasionally become sterile; and if such insects had been social, and it had been profitable to the community that a number should have been annually born capable of work, but incapable of procreation, I can see no very great difficulty in this being effected by natural selection. But I must pass over this preliminary difficulty. The great difficulty lies in the working ants differing widely from both the males and the fertile females in structure, as in the shape of the thorax and in being destitute of wings and sometimes of eyes, and in instinct. As far as instinct alone is concerned, the prodigious difference in this respect between the workers and the perfect females, would have been far better exemplified by the hive-bee. If a working ant or other neuter insect had been an animal in the ordinary state, I should have unhesitatingly assumed that all its characters had been slowly acquired through natural selection; namely, by an individual having been born with some slight profitable modification of structure, this being inherited by its offspring, which again varied and were again selected, and so onwards. But with the working ant we have an insect differing greatly from its parents, yet absolutely sterile; so that it could never have transmitted successively acquired modifications of structure or instinct to its progeny. It may well be asked how is it possible to reconcile this case with the theory of natural selection?

First, let it be remembered that we have innumerable instances, both in our domestic productions and in those in a state of nature, of all sorts of differences of structure which have become correlated to certain ages, and to either sex. We have differences correlated not only to one sex, but to that short period alone when the reproductive system is active, as in the nuptial plumage of many birds, and in the hooked jaws of the male salmon. We have even slight differences in the horns of different breeds of cattle in relation to an artificially imperfect state of the male sex; for oxen of certain breeds have longer horns than in other breeds, in comparison with the horns of the bulls or cows of these same breeds. Hence I can see no real difficulty in any character having become correlated with the sterile condition of certain members of insect-communities: the difficulty lies in understanding how such correlated modifications of structure could have been slowly accumulated by natural selection.

This difficulty, though appearing insuperable, is lessened, or, as I believe, disappears, when it is remembered that selection may be applied to the family, as well as to the individual, and may thus gain the desired end. Thus, a well-flavoured vegetable is cooked, and the individual is destroyed; but the horticulturist sows seeds of the same stock, and confidently expects to get nearly the same variety; breeders of cattle wish the flesh and fat to be well marbled together; the animal has been slaughtered, but the breeder goes with confidence to the same family. I have such faith in the powers of selection, that I do not doubt that a breed of cattle, always yielding oxen with extraordinarily long horns, could be slowly formed by carefully watching which individual bulls and cows, when matched, produced oxen with the longest horns; and yet no one ox could ever have propagated its kind. Thus I believe it has been with social insects: a slight modification of structure, or instinct, correlated with the sterile condition of certain members of the community, has been advantageous to the community: consequently the fertile males and females of the same community flourished, and transmitted to their fertile offspring a tendency to produce sterile members having the same modification. And I believe that this process has been repeated, until that prodigious amount of difference between the fertile and sterile females of the same species has been produced, which we see in many social insects.

But we have not as yet touched on the climax of the difficulty; namely, the fact that the neuters of several ants differ, not only from the fertile females and males, but from each other, sometimes to an almost incredible degree, and are thus divided into two or even three castes. The castes, moreover, do not generally graduate into each other, but are perfectly well defined; being as distinct from each other, as are any two species of the same genus, or rather as any two genera of the same family. Thus in Eciton, there are working and soldier neuters, with jaws and instincts extraordinarily different: in Cryptocerus, the workers of one caste alone carry a wonderful sort of shield on their heads, the use of which is quite unknown: in the Mexican Myrmecocystus, the workers of one caste never leave the nest; they are fed by the workers of another caste, and they have an enormously developed abdomen which secretes a sort of honey, supplying the place of that excreted by the aphides, or the domestic cattle as they may be called, which our European ants guard or imprison.

It will indeed be thought that I have an overweening confidence in the principle of natural selection, when I do not admit that such wonderful and well-established facts at once annihilate my theory. In the simpler case of neuter insects all of one caste or of the same kind, which have been rendered by natural selection, as I believe to be quite possible, different from the fertile males and females, in this case, we may safely conclude from the analogy of ordinary variations, that each successive, slight, profitable modification did not probably at first appear in all the individual neuters in the same nest, but in a few alone; and that by the long-continued selection of the fertile parents which produced most neuters with the profitable modification, all the neuters ultimately came to have the desired character. On this view we ought occasionally to find neuter-insects of the same species, in the same nest, presenting gradations of structure; and this we do find, even often, considering how few neuter-insects out of Europe have been carefully examined. Mr F. Smith has shown how surprisingly the neuters of several British ants differ from each other in size and sometimes in colour; and that the extreme forms can sometimes be perfectly linked together by individuals taken out of the same nest: I have myself compared perfect gradations of this kind. It often happens that the larger or the smaller sized workers are the most numerous; or that both large and small are numerous, with those of an intermediate size scanty in numbers. Formica flava has larger and smaller workers, with some of intermediate size; and, in this species, as Mr F. Smith has observed, the larger workers have simple eyes (ocelli), which though small can be plainly distinguished, whereas the smaller workers have their ocelli rudimentary. Having carefully dissected several specimens of these workers, I can affirm that the eyes are far more rudimentary in the smaller workers than can be accounted for merely by their proportionally lesser size; and I fully believe, though I dare not assert so positively, that the workers of intermediate size have their ocelli in an exactly intermediate condition. So that we here have two bodies of sterile workers in the same nest, differing not only in size, but in their organs of vision, yet connected by some few members in an intermediate condition. I may digress by adding, that if the smaller workers had been the most useful to the community, and those males and females had been continually selected, which produced more and more of the smaller workers, until all the workers had come to be in this condition; we should then have had a species of ant with neuters very nearly in the same condition with those of Myrmica. For the workers of Myrmica have not even rudiments of ocelli, though the male and female ants of this genus have well-developed ocelli.

I may give one other case: so confidently did I expect to find gradations in important points of structure between the different castes of neuters in the same species, that I gladly availed myself of Mr F. Smith's offer of numerous specimens from the same nest of the driver ant (Anomma) of West Africa. The reader will perhaps best appreciate the amount of difference in these workers, by my giving not the actual measurements, but a strictly accurate illustration: the difference was the same as if we were to see a set of workmen building a house of whom many were five feet four inches high, and many sixteen feet high; but we must suppose that the larger workmen had heads four instead of three times as big as those of the smaller men, and jaws nearly five times as big. The jaws, moreover, of the working ants of the several sizes differed wonderfully in shape, and in the form and number of the teeth. But the important fact for us is, that though the workers can be grouped into castes of different sizes, yet they graduate insensibly into each other, as does the widely-different structure of their jaws. I speak confidently on this latter point, as Mr Lubbock made drawings for me with the camera lucida of the jaws which I had dissected from the workers of the several sizes.

With these facts before me, I believe that natural selection, by acting on the fertile parents, could form a species which should regularly produce neuters, either all of large size with one form of jaw, or all of small size with jaws having a widely different structure; or lastly, and this is our climax of difficulty, one set of workers of one size and structure, and simultaneously another set of workers of a different size and structure; a graduated series having been first formed, as in the case of the driver ant, and then the extreme forms, from being the most useful to the community, having been produced in greater and greater numbers through the natural selection of the parents which generated them; until none with an intermediate structure were produced.

Thus, as I believe, the wonderful fact of two distinctly defined castes of sterile workers existing in the same nest, both widely different from each other and from their parents, has originated. We can see how useful their production may have been to a social community of insects, on the same principle that the division of labour is useful to civilised man. As ants work by inherited instincts and by inherited tools or weapons, and not by acquired knowledge and manufactured instruments, a perfect division of labour could be effected with them only by the workers being sterile; for had they been fertile, they would have intercrossed, and their instincts and structure would have become blended. And nature has, as I believe, effected this admirable division of labour in the communities of ants, by the means of natural selection. But I am bound to confess, that, with all my faith in this principle, I should never have anticipated that natural selection could have been efficient in so high a degree, had not the case of these neuter insects convinced me of the fact. I have, therefore, discussed this case, at some little but wholly insufficient length, in order to show the power of natural selection, and likewise because this is by far the most serious special difficulty, which my theory has encountered. The case, also, is very interesting, as it proves that with animals, as with plants, any amount of modification in structure can be effected by the accumulation of numerous, slight, and as we must call them accidental, variations, which are in any manner profitable, without exercise or habit having come into play. For no amount of exercise, or habit, or volition, in the utterly sterile members of a community could possibly have affected the structure or instincts of the fertile members, which alone leave descendants. I am surprised that no one has advanced this demonstrative case of neuter insects, against the well-known doctrine of Lamarck.

Summary. I have endeavoured briefly in this chapter to show that the mental qualities of our domestic animals vary, and that the variations are inherited. Still more briefly I have attempted to show that instincts vary slightly in a state of nature. No one will dispute that instincts are of the highest importance to each animal. Therefore I can see no difficulty, under changing conditions of life, in natural selection accumulating slight modifications of instinct to any extent, in any useful direction. In some cases habit or use and disuse have probably come into play. I do not pretend that the facts given in this chapter strengthen in any great degree my theory; but none of the cases of difficulty, to the best of my judgment, annihilate it. On the other hand, the fact that instincts are not always absolutely perfect and are liable to mistakes; that no instinct has been produced for the exclusive good of other animals, but that each animal takes advantage of the instincts of others; that the canon in natural history, of 'natura non facit saltum' is applicable to instincts as well as to corporeal structure, and is plainly explicable on the foregoing views, but is otherwise inexplicable, all tend to corroborate the theory of natural selection.

This theory is, also, strengthened by some few other facts in regard to instincts; as by that common case of closely allied, but certainly distinct, species, when inhabiting distant parts of the world and living under considerably different conditions of life, yet often retaining nearly the same instincts. For instance, we can understand on the principle of inheritance, how it is that the thrush of South America lines its nest with mud, in the same peculiar manner as does our British thrush: how it is that the male wrens (Troglodytes) of North America, build 'cock-nests,' to roost in, like the males of our distinct Kitty-wrens, a habit wholly unlike that of any other known bird. Finally, it may not be a logical deduction, but to my imagination it is far more satisfactory to look at such instincts as the young cuckoo ejecting its foster-brothers, ants making slaves, -- the larvae of ichneumonidae feeding within the live bodies of caterpillars, not as specially endowed or created instincts, but as small consequences of one general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die. 
THE view generally entertained by naturalists is that species, when intercrossed, have been specially endowed with the quality of sterility, in order to prevent the confusion of all organic forms. This view certainly seems at first probable, for species within the same country could hardly have kept distinct had they been capable of crossing freely. The importance of the fact that hybrids are very generally sterile, has, I think, been much underrated by some late writers. On the theory of natural selection the case is especially important, inasmuch as the sterility of hybrids could not possibly be of any advantage to them, and therefore could not have been acquired by the continued preservation of successive profitable degrees of sterility. I hope, however, to be able to show that sterility is not a specially acquired or endowed quality, but is incidental on other acquired differences.

In treating this subject, two classes of facts, to a large extent fundamentally different, have generally been confounded together; namely, the sterility of two species when first crossed, and the sterility of the hybrids produced from them.

Pure species have of course their organs of reproduction in a perfect condition, yet when intercrossed they produce either few or no offspring. Hybrids, on the other hand, have their reproductive organs functionally impotent, as may be clearly seen in the state of the male element in both plants and animals; though the organs themselves are perfect in structure, as far as the microscope reveals. In the first case the two sexual elements which go to form the embryo are perfect; in the second case they are either not at all developed, or are imperfectly developed. This distinction is important, when the cause of the sterility, which is common to the two cases, has to be considered. The distinction has probably been slurred over, owing to the sterility in both cases being looked on as a special endowment, beyond the province of our reasoning powers.

The fertility of varieties, that is of the forms known or believed to have descended from common parents, when intercrossed, and likewise the fertility of their mongrel offspring, is, on my theory, of equal importance with the sterility of species; for it seems to make a broad and clear distinction between varieties and species.

First, for the sterility of species when crossed and of their hybrid offspring. It is impossible to study the several memoirs and works of those two conscientious and admirable observers, Kölreuter and Gärtner, who almost devoted their lives to this subject, without being deeply impressed with the high generality of some degree of sterility. Kölreuter makes the rule universal; but then he cuts the knot, for in ten cases in which he found two forms, considered by most authors as distinct species, quite fertile together, he unhesitatingly ranks them as varieties. Gärtner, also, makes the rule equally universal; and he disputes the entire fertility of Kölreuter's ten cases. But in these and in many other cases, Gärtner is obliged carefully to count the seeds, in order to show that there is any degree of sterility. He always compares the maximum number of seeds produced by two species when crossed and by their hybrid offspring, with the average number produced by both pure parent-species in a state of nature. But a serious cause of error seems to me to be here introduced: a plant to be hybridised must be castrated, and, what is often more important, must be secluded in order to prevent pollen being brought to it by insects from other plants. Nearly all the plants experimentised on by Gärtner were potted, and apparently were kept in a chamber in his house. That these processes are often injurious to the fertility of a plant cannot be doubted; for Gärtner gives in his table about a score of cases of plants which he castrated, and artificially fertilised with their own pollen, and (excluding all cases such as the Leguminosae, in which there is an acknowledged difficulty in the manipulation) half of these twenty plants had their fertility in some degree impaired. Moreover, as Gärtner during several years repeatedly crossed the primrose and cowslip, which we have such good reason to believe to be varieties, and only once or twice succeeded in getting fertile seed; as he found the common red and blue pimpernels (Anagallis arvensis and coerulea), which the best botanists rank as varieties, absolutely sterile together; and as he came to the same conclusion in several other analogous cases; it seems to me that we may well be permitted to doubt whether many other species are really so sterile, when intercrossed, as Gärtner believes.

It is certain, on the one hand, that the sterility of various species when crossed is so different in degree and graduates away so insensibly, and, on the other hand, that the fertility of pure species is so easily affected by various circumstances, that for all practical purposes it is most difficult to say where perfect fertility ends and sterility begins. I think no better evidence of this can be required than that the two most experienced observers who have ever lived, namely, Kölreuter and Gärtner, should have arrived at diametrically opposite conclusions in regard to the very same species. It is also most instructive to compare but I have not space here to enter on details the evidence advanced by our best botanists on the question whether certain doubtful forms should be ranked as species or varieties, with the evidence from fertility adduced by different hybridisers, or by the same author, from experiments made during different years. It can thus be shown that neither sterility nor fertility affords any clear distinction between species and varieties; but that the evidence from this source graduates away, and is doubtful in the same degree as is the evidence derived from other constitutional and structural differences.

In regard to the sterility of hybrids in successive generations; though Gärtner was enabled to rear some hybrids, carefully guarding them from a cross with either pure parent, for six or seven, and in one case for ten generations, yet he asserts positively that their fertility never increased, but generally greatly decreased. I do not doubt that this is usually the case, and that the fertility often suddenly decreases in the first few generations. Nevertheless I believe that in all these experiments the fertility has been diminished by an independent cause, namely, from close interbreeding. I have collected so large a body of facts, showing that close interbreeding lessens fertility, and, on the other hand, that an occasional cross with a distinct individual or variety increases fertility, that I cannot doubt the correctness of this almost universal belief amongst breeders. Hybrids are seldom raised by experimentalists in great numbers; and as the parent-species, or other allied hybrids, generally grow in the same garden, the visits of insects must be carefully prevented during the flowering season: hence hybrids will generally be fertilised during each generation by their own individual pollen; and I am convinced that this would be injurious to their fertility, already lessened by their hybrid origin. I am strengthened in this conviction by a remarkable statement repeatedly made by Gärtner, namely, that if even the less fertile hybrids be artificially fertilised with hybrid pollen of the same kind, their fertility, notwithstanding the frequent ill effects of manipulation, sometimes decidedly increases, and goes on increasing. Now, in artificial fertilisation pollen is as often taken by chance (as I know from my own experience) from the anthers of another flower, as from the anthers of the flower itself which is to be fertilised; so that a cross between two flowers, though probably on the same plant, would be thus effected. Moreover, whenever complicated experiments are in progress, so careful an observer as Gärtner would have castrated his hybrids, and this would have insured in each generation a cross with the pollen from a distinct flower, either from the same plant or from another plant of the same hybrid nature. And thus, the strange fact of the increase of fertility in the successive generations of artificially fertilised hybrids may, I believe, be accounted for by close interbreeding having been avoided.

Now let us turn to the results arrived at by the third most experienced hybridiser, namely, the Hon. and Rev. W. Herbert. He is as emphatic in his conclusion that some hybrids are perfectly fertile as fertile as the pure parent-species as are Kölreuter and Gärtner that some degree of sterility between distinct species is a universal law of nature. He experimentised on some of the very same species as did Gärtner. The difference in their results may, I think, be in part accounted for by Herbert's great horticultural skill, and by his having hothouses at his command. Of his many important statements I will here give only a single one as an example, namely, that 'every ovule in a pod of Crinum capense fertilised by C. revolutum produced a plant, which (he says) I never saw to occur in a case of its natural fecundation.' So that we here have perfect, or even more than commonly perfect, fertility in a first cross between two distinct species.

This case of the Crinum leads me to refer to a most singular fact, namely, that there are individual plants, as with certain species of Lobelia, and with all the species of the genus Hippeastrum, which can be far more easily fertilised by the pollen of another and distinct species, than by their own pollen. For these plants have been found to yield seed to the pollen of a distinct species, though quite sterile with their own pollen, notwithstanding that their own pollen was found to be perfectly good, for it fertilised distinct species. So that certain individual plants and all the individuals of certain species can actually be hybridised much more readily than they can be self-fertilised! For instance, a bulb of Hippeastrum aulicum produced four flowers; three were fertilised by Herbert with their own pollen, and the fourth was subsequently fertilised by the pollen of a compound hybrid descended from three other and distinct species: the result was that 'the ovaries of the three first flowers soon ceased to grow, and after a few days perished entirely, whereas the pod impregnated by the pollen of the hybrid made vigorous growth and rapid progress to maturity, and bore good seed, which vegetated freely.' In a letter to me, in 1839, Mr Herbert told me that he had then tried the experiment during five years, and he continued to try it during several subsequent years, and always with the same result. This result has, also, been confirmed by other observers in the case of Hippeastrum with its sub-genera, and in the case of some other genera, as Lobelia, Passiflora and Verbascum. Although the plants in these experiments appeared perfectly healthy, and although both the ovules and pollen of the same flower were perfectly good with respect to other species, yet as they were functionally imperfect in their mutual self-action, we must infer that the plants were in an unnatural state. Nevertheless these facts show on what slight and mysterious causes the lesser or greater fertility of species when crossed, in comparison with the same species when self-fertilised, sometimes depends.

The practical experiments of horticulturists, though not made with scientific precision, deserve some notice. It is notorious in how complicated a manner the species of Pelargonium, Fuchsia, Calceolaria, Petunia, Rhododendron, &c., have been crossed, yet many of these hybrids seed freely. For instance, Herbert asserts that a hybrid from Calceolaria integrifolia and plantaginea, species most widely dissimilar in general habit, 'reproduced itself as perfectly as if it had been a natural species from the mountains of Chile.' I have taken some pains to ascertain the degree of fertility of some of the complex crosses of Rhododendrons, and I am assured that many of them are perfectly fertile. Mr C. Noble, for instance, informs me that he raises stocks for grafting from a hybrid between Rhod. Ponticum and Catawbiense, and that this hybrid 'seeds as freely as it is possible to imagine.' Had hybrids, when fairly treated, gone on decreasing in fertility in each successive generation, as Gärtner believes to be the case, the fact would have been notorious to nurserymen. Horticulturists raise large beds of the same hybrids, and such alone are fairly treated, for by insect agency the several individuals of the same hybrid variety are allowed to freely cross with each other, and the injurious influence of close interbreeding is thus prevented. Any one may readily convince himself of the efficiency of insect-agency by examining the flowers of the more sterile kinds of hybrid rhododendrons, which produce no pollen, for he will find on their stigmas plenty of pollen brought from other flowers.

In regard to animals, much fewer experiments have been carefully tried than with plants. If our systematic arrangements can be trusted, that is if the genera of animals are as distinct from each other, as are the genera of plants, then we may infer that animals more widely separated in the scale of nature can be more easily crossed than in the case of plants; but the hybrids themselves are, I think, more sterile. I doubt whether any case of a perfectly fertile hybrid animal can be considered as thoroughly well authenticated. It should, however, be borne in mind that, owing to few animals breeding freely under confinement, few experiments have been fairly tried: for instance, the canary-bird has been crossed with nine other finches, but as not one of these nine species breeds freely in confinement, we have no right to expect that the first crosses between them and the canary, or that their hybrids, should be perfectly fertile. Again, with respect to the fertility in successive generations of the more fertile hybrid animals, I hardly know of an instance in which two families of the same hybrid have been raised at the same time from different parents, so as to avoid the ill effects of close interbreeding. On the contrary, brothers and sisters have usually been crossed in each successive generation, in opposition to the constantly repeated admonition of every breeder. And in this case, it is not at all surprising that the inherent sterility in the hybrids should have gone on increasing. If we were to act thus, and pair brothers and sisters in the case of any pure animal, which from any cause had the least tendency to sterility, the breed would assuredly be lost in a very few generations.

Although I do not know of any thoroughly well-authenticated cases of perfectly fertile hybrid animals, I have some reason to believe that the hybrids from Cervulus vaginalis and Reevesii, and from Phasianus colchicus with p. torquatus and with p. versicolor are perfectly fertile. The hybrids from the common and Chinese geese (A. cygnoides), species which are so different that they are generally ranked in distinct genera, have often bred in this country with either pure parent, and in one single instance they have bred inter se. This was effected by Mr Eyton, who raised two hybrids from the same parents but from different hatches; and from these two birds he raised no less than eight hybrids (grandchildren of the pure geese) from one nest. In India, however, these cross-bred geese must be far more fertile; for I am assured by two eminently capable judges, namely Mr Blyth and Capt. Hutton, that whole flocks of these crossed geese are kept in various parts of the country; and as they are kept for profit, where neither pure parent-species exists, they must certainly be highly fertile.

A doctrine which originated with Pallas, has been largely accepted by modern naturalists; namely, that most of our domestic animals have descended from two or more aboriginal species, since commingled by intercrossing. On this view, the aboriginal species must either at first have produced quite fertile hybrids, or the hybrids must have become in subsequent generations quite fertile under domestication. This latter alternative seems to me the most probable, and I am inclined to believe in its truth, although its rests on no direct evidence. I believe, for instance, that our dogs have descended from several wild stocks; yet, with perhaps the exception of certain indigenous domestic dogs of South America, all are quite fertile together; and analogy makes me greatly doubt, whether the several aboriginal species would at first have freely bred together and have produced quite fertile hybrids. So again there is reason to believe that our European and the humped Indian cattle are quite fertile together; but from facts communicated to me by Mr Blyth, I think they must be considered as distinct species. On this view of the origin of many of our domestic animals, we must either give up the belief of the almost universal sterility of distinct species of animals when crossed; or we must look at sterility, not as an indelible characteristic, but as one capable of being removed by domestication.

Finally, looking to all the ascertained facts on the intercrossing of plants and animals, it may be concluded that some degree of sterility, both in first crosses and in hybrids, is an extremely general result; but that it cannot, under our present state of knowledge, be considered as absolutely universal.

Laws governing the Sterility of first Crosses and of Hybrids. We will now consider a little more in detail the circumstances and rules governing the sterility of first crosses and of hybrids. Our chief object will be to see whether or not the rules indicate that species have specially been endowed with this quality, in order to prevent their crossing and blending together in utter confusion. The following rules and conclusions are chiefly drawn up from Gärtner's admirable work on the hybridisation of plants. I have taken much pains to ascertain how far the rules apply to animals, and considering how scanty our knowledge is in regard to hybrid animals, I have been surprised to find how generally the same rules apply to both kingdoms.

It has been already remarked, that the degree of fertility, both of first crosses and of hybrids, graduates from zero to perfect fertility. It is surprising in how many curious ways this gradation can be shown to exist; but only the barest outline of the facts can here be given. When pollen from a plant of one family is placed on the stigma of a plant of a distinct family, it exerts no more influence than so much inorganic dust. From this absolute zero of fertility, the pollen of different species of the same genus applied to the stigma of some one species, yields a perfect gradation in the number of seeds produced, up to nearly complete or even quite complete fertility; and, as we have seen, in certain abnormal cases, even to an excess of fertility, beyond that which the plant's own pollen will produce. So in hybrids themselves, there are some which never have produced, and probably never would produce, even with the pollen of either pure parent, a single fertile seed: but in some of these cases a first trace of fertility may be detected, by the pollen of one of the pure parent-species causing the flower of the hybrid to wither earlier than it otherwise would have done; and the early withering of the flower is well known to be a sign of incipient fertilisation. From this extreme degree of sterility we have self-fertilised hybrids producing a greater and greater number of seeds up to perfect fertility.

Hybrids from two species which are very difficult to cross, and which rarely produce any offspring, are generally very sterile; but the parallelism between the difficulty of making a first cross, and the sterility of the hybrids thus produced two classes of facts which are generally confounded together is by no means strict. There are many cases, in which two pure species can be united with unusual facility, and produce numerous hybrid-offspring, yet these hybrids are remarkably sterile. On the other hand, there are species which can be crossed very rarely, or with extreme difficulty, but the hybrids, when at last produced, are very fertile. Even within the limits of the same genus, for instance in Dianthus, these two opposite cases occur.

The fertility, both of first crosses and of hybrids, is more easily affected by unfavourable conditions, than is the fertility of pure species. But the degree of fertility is likewise innately variable; for it is not always the same when the same two species are crossed under the same circumstances, but depends in part upon the constitution of the individuals which happen to have been chosen for the experiment. So it is with hybrids, for their degree of fertility is often found to differ greatly in the several individuals raised from seed out of the same capsule and exposed to exactly the same conditions.

By the term systematic affinity is meant, the resemblance between species in structure and in constitution, more especially in the structure of parts which are of high physiological importance and which differ little in the allied species. Now the fertility of first crosses between species, and of the hybrids produced from them, is largely governed by their systematic affinity. This is clearly shown by hybrids never having been raised between species ranked by systematists in distinct families; and on the other hand, by very closely allied species generally uniting with facility. But the correspondence between systematic affinity and the facility of crossing is by no means strict. A multitude of cases could be given of very closely allied species which will not unite, or only with extreme difficulty; and on the other hand of very distinct species which unite with the utmost facility. In the same family there may be a genus, as Dianthus, in which very many species can most readily be crossed; and another genus, as Silene, in which the most persevering efforts have failed to produce between extremely close species a single hybrid. Even within the limits of the same genus, we meet with this same difference; for instance, the many species of Nicotiana have been more largely crossed than the species of almost any other genus; but Gärtner found that N. acuminata, which is not a particularly distinct species, obstinately failed to fertilise, or to be fertilised by, no less than eight other species of Nicotiana. Very many analogous facts could be given.

No one has been able to point out what kind, or what amount, of difference in any recognisable character is sufficient to prevent two species crossing. It can be shown that plants most widely different in habit and general appearance, and having strongly marked differences in every part of the flower, even in the pollen, in the fruit, and in the cotyledons, can be crossed. Annual and perennial plants, deciduous and evergreen trees, plants inhabiting different stations and fitted for extremely different climates, can often be crossed with ease.

By a reciprocal cross between two species, I mean the case, for instance, of a stallion-horse being first crossed with a female-ass, and then a male-ass with a mare: these two species may then be said to have been reciprocally crossed. There is often the widest possible difference in the facility of making reciprocal crosses. Such cases are highly important, for they prove that the capacity in any two species to cross is often completely independent of their systematic affinity, or of any recognisable difference in their whole organisation. On the other hand, these cases clearly show that the capacity for crossing is connected with constitutional differences imperceptible by us, and confined to the reproductive system. This difference in the result of reciprocal crosses between the same two species was long ago observed by Kölreuter. To give an instance: Mirabilis jalappa can easily be fertilised by the pollen of M. longiflora, and the hybrids thus produced are sufficiently fertile; but Kölreuter tried more than two hundred times, during eight following years, to fertilise reciprocally M. longiflora with the pollen of M. jalappa, and utterly failed. Several other equally striking cases could be given. Thuret has observed the same fact with certain sea-weeds or Fuci. Gärtner, moreover, found that this difference of facility in making reciprocal crosses is extremely common in a lesser degree. He has observed it even between forms so closely related (as Matthiola annua and glabra) that many botanists rank them only as varieties. It is also a remarkable fact, that hybrids raised from reciprocal crosses, though of course compounded of the very same two species, the one species having first been used as the father and then as the mother, generally differ in fertility in a small, and occasionally in a high degree.

Several other singular rules could be given from Gärtner: for instance, some species have a remarkable power of crossing with other species; other species of the same genus have a remarkable power of impressing their likeness on their hybrid offspring; but these two powers do not at all necessarily go together. There are certain hybrids which instead of having, as is usual, an intermediate character between their two parents, always closely resemble one of them; and such hybrids, though externally so like one of their pure parent-species, are with rare exceptions extremely sterile. So again amongst hybrids which are usually intermediate in structure between their parents, exceptional and abnormal individuals sometimes are born, which closely resemble one of their pure parents; and these hybrids are almost always utterly sterile, even when the other hybrids raised from seed from the same capsule have a considerable degree of fertility. These facts show how completely fertility in the hybrid is independent of its external resemblance to either pure parent.

Considering the several rules now given, which govern the fertility of first crosses and of hybrids, we see that when forms, which must be considered as good and distinct species, are united, their fertility graduates from zero to perfect fertility, or even to fertility under certain conditions in excess. That their fertility, besides being eminently susceptible to favourable and unfavourable conditions, is innately variable. That it is by no means always the same in degree in the first cross and in the hybrids produced from this cross. That the fertility of hybrids is not related to the degree in which they resemble in external appearance either parent. And lastly, that the facility of making a first cross between any two species is not always governed by their systematic affinity or degree of resemblance to each other. This latter statement is clearly proved by reciprocal crosses between the same two species, for according as the one species or the other is used as the father or the mother, there is generally some difference, and occasionally the widest possible difference, in the facility of effecting an union. The hybrids, moreover, produced from reciprocal crosses often differ in fertility.

Now do these complex and singular rules indicate that species have been endowed with sterility simply to prevent their becoming confounded in nature? I think not. For why should the sterility be so extremely different in degree, when various species are crossed, all of which we must suppose it would be equally important to keep from blending together? Why should the degree of sterility be innately variable in the individuals of the same species? Why should some species cross with facility, and yet produce very sterile hybrids; and other species cross with extreme difficulty, and yet produce fairly fertile hybrids? Why should there often be so great a difference in the result of a reciprocal cross between the same two species? Why, it may even be asked, has the production of hybrids been permitted? To grant to species the special power of producing hybrids, and then to stop their further propagation by different degrees of sterility, not strictly related to the facility of the first union between their parents, seems to be a strange arrangement.

The foregoing rules and facts, on the other hand, appear to me clearly to indicate that the sterility both of first crosses and of hybrids is simply incidental or dependent on unknown differences, chiefly in the reproductive systems, of the species which are crossed. The differences being of so peculiar and limited a nature, that, in reciprocal crosses between two species the male sexual element of the one will often freely act on the female sexual element of the other, but not in a reversed direction. It will be advisable to explain a little more fully by an example what I mean by sterility being incidental on other differences, and not a specially endowed quality. As the capacity of one plant to be grafted or budded on another is so entirely unimportant for its welfare in a state of nature, I presume that no one will suppose that this capacity is a specially endowed quality, but will admit that it is incidental on differences in the laws of growth of the two plants. We can sometimes see the reason why one tree will not take on another, from differences in their rate of growth, in the hardness of their wood, in the period of the flow or nature of their sap, &c.; but in a multitude of cases we can assign no reason whatever. Great diversity in the size of two plants, one being woody and the other herbaceous, one being evergreen and the other deciduous, and adaptation to widely different climates, does not always prevent the two grafting together. As in hybridisation, so with grafting, the capacity is limited by systematic affinity, for no one has been able to graft trees together belonging to quite distinct families; and, on the other hand, closely allied species, and varieties of the same species, can usually, but not invariably, be grafted with ease. But this capacity, as in hybridisation, is by no means absolutely governed by systematic affinity. Although many distinct genera within the same family have been grafted together, in other cases species of the same genus will not take on each other. The pear can be grafted far more readily on the quince, which is ranked as a distinct genus, than on the apple, which is a member of the same genus. Even different varieties of the pear take with different degrees of facility on the quince; so do different varieties of the apricot and peach on certain varieties of the plum.

As Gärtner found that there was sometimes an innate difference in different individuals of the same two species in crossing; so Sagaret believes this to be the case with different individuals of the same two species in being grafted together. As in reciprocal crosses, the facility of effecting an union is often very far from equal, so it sometimes is in grafting; the common gooseberry, for instance, cannot be grafted on the currant, whereas the currant will take, though with difficulty, on the gooseberry.

We have seen that the sterility of hybrids, which have their reproductive organs in an imperfect condition, is a very different case from the difficulty of uniting two pure species, which have their reproductive organs perfect; yet these two distinct cases run to a certain extent parallel. Something analogous occurs in grafting; for Thouin found that three species of Robinia, which seeded freely on their own roots, and which could be grafted with no great difficulty on another species, when thus grafted were rendered barren. On the other hand, certain species of Sorbus, when grafted on other species, yielded twice as much fruit as when on their own roots. We are reminded by this latter fact of the extraordinary case of Hippeastrum, Lobelia, &c., which seeded much more freely when fertilised with the pollen of distinct species, than when self-fertilised with their own pollen.

We thus see, that although there is a clear and fundamental difference between the mere adhesion of grafted stocks, and the union of the male and female elements in the act of reproduction, yet that there is a rude degree of parallelism in the results of grafting and of crossing distinct species. And as we must look at the curious and complex laws governing the facility with which trees can be grafted on each other as incidental on unknown differences in their vegetative systems, so I believe that the still more complex laws governing the facility of first crosses, are incidental on unknown differences, chiefly in their reproductive systems. These differences, in both cases, follow to a certain extent, as might have been expected, systematic affinity, by which every kind of resemblance and dissimilarity between organic beings is attempted to be expressed. The facts by no means seem to me to indicate that the greater or lesser difficulty of either grafting or crossing together various species has been a special endowment; although in the case of crossing, the difficulty is as important for the endurance and stability of specific forms, as in the case of grafting it is unimportant for their welfare.

Causes of the Sterility of first Crosses and of Hybrids. We may now look a little closer at the probable causes of the sterility of first crosses and of hybrids. These two cases are fundamentally different, for, as just remarked, in the union of two pure species the male and female sexual elements are perfect, whereas in hybrids they are imperfect. Even in first crosses, the greater or lesser difficulty in effecting a union apparently depends on several distinct causes. There must sometimes be a physical impossibility in the male element reaching the ovule, as would be the case with a plant having a pistil too long for the pollen-tubes to reach the ovarium. It has also been observed that when pollen of one species is placed on the stigma of a distantly allied species, though the pollen-tubes protrude, they do not penetrate the stigmatic surface. Again, the male element may reach the female element, but be incapable of causing an embryo to be developed, as seems to have been the case with some of Thuret's experiments on Fuci. No explanation can be given of these facts, any more than why certain trees cannot be grafted on others. Lastly, an embryo may be developed, and then perish at an early period. This latter alternative has not been sufficiently attended to; but I believe, from observations communicated to me by Mr. Hewitt, who has had great experience in hybridising gallinaceous birds, that the early death of the embryo is a very frequent cause of sterility in first crosses. I was at first very unwilling to believe in this view; as hybrids, when once born, are generally healthy and long-lived, as we see in the case of the common mule. Hybrids, however, are differently circumstanced before and after birth: when born and living in a country where their two parents can live, they are generally placed under suitable conditions of life. But a hybrid partakes of only half of the nature and constitution of its mother, and therefore before birth, as long as it is nourished within its mother's womb or within the egg or seed produced by the mother, it may be exposed to conditions in some degree unsuitable, and consequently be liable to perish at an early period; more especially as all very young beings seem eminently sensitive to injurious or unnatural conditions of life.

In regard to the sterility of hybrids, in which the sexual elements are imperfectly developed, the case is very different. I have more than once alluded to a large body of facts, which I have collected, showing that when animals and plants are removed from their natural conditions, they are extremely liable to have their reproductive systems seriously affected. This, in fact, is the great bar to the domestication of animals. Between the sterility thus superinduced and that of hybrids, there are many points of similarity. In both cases the sterility is independent of general health, and is often accompanied by excess of size or great luxuriance. In both cases, the sterility occurs in various degrees; in both, the male element is the most liable to be affected; but sometimes the female more than the male. In both, the tendency goes to a certain extent with systematic affinity, or whole groups of animals and plants are rendered impotent by the same unnatural conditions; and whole groups of species tend to produce sterile hybrids. On the other hand, one species in a group will sometimes resist great changes of conditions with unimpaired fertility; and certain species in a group will produce unusually fertile hybrids. No one can tell, till he tries, whether any particular animal will breed under confinement or any plant seed freely under culture; nor can he tell, till he tries, whether any two species of a genus will produce more or less sterile hybrids. Lastly, when organic beings are placed during several generations under conditions not natural to them, they are extremely liable to vary, which is due, as I believe, to their reproductive systems having been specially affected, though in a lesser degree than when sterility ensues. So it is with hybrids, for hybrids in successive generations are eminently liable to vary, as every experimentalist has observed.

Thus we see that when organic beings are placed under new and unnatural conditions, and when hybrids are produced by the unnatural crossing of two species, the reproductive system, independently of the general state of health, is affected by sterility in a very similar manner. In the one case, the conditions of life have been disturbed, though often in so slight a degree as to be inappreciable by us; in the other case, or that of hybrids,the external conditions have remained the same, but the organisation has been disturbed by two different structures and constitutions having been blended into one. For it is scarcely possible that two organisations should be compounded into one, without some disturbance occurring in the development, or periodical action, or mutual relation of the different parts and organs one to another, or to the conditions of life. When hybrids are able to breed inter se, they transmit to their offspring from generation to generation the same compounded organisation, and hence we need not be surprised that their sterility, though in some degree variable, rarely diminishes.

It must, however, be confessed that we cannot understand, excepting on vague hypotheses, several facts with respect to the sterility of hybrids; for instance, the unequal fertility of hybrids produced from reciprocal crosses; or the increased sterility in those hybrids which occasionally and exceptionally resemble closely either pure parent. Nor do I pretend that the foregoing remarks go to the root of the matter: no explanation is offered why an organism, when placed under unnatural conditions, is rendered sterile. All that I have attempted to show, is that in two cases, in some respects allied, sterility is the common result, in the one case from the conditions of life having been disturbed, in the other case from the organisation having been disturbed by two organisations having been compounded into one.

It may seem fanciful, but I suspect that a similar parallelism extends to an allied yet very different class of facts. It is an old and almost universal belief, founded, I think, on a considerable body of evidence, that slight changes in the conditions of life are beneficial to all living things. We see this acted on by farmers and gardeners in their frequent exchanges of seed, tubers, &c., from one soil or climate to another, and back again. During the convalescence of animals, we plainly see that great benefit is derived from almost any change in the habits of life. Again, both with plants and animals, there is abundant evidence, that a cross between very distinct individuals of the same species, that is between members of different strains or sub-breeds, gives vigour and fertility to the offspring. I believe, indeed, from the facts alluded to in our fourth chapter, that a certain amount of crossing is indispensable even with hermaphrodites; and that close interbreeding continued during several generations between the nearest relations, especially if these be kept under the same conditions of life, always induces weakness and sterility in the progeny.

Hence it seems that, on the one hand, slight changes in the conditions of life benefit all organic beings, and on the other hand, that slight crosses, that is crosses between the males and females of the same species which have varied and become slightly different, give vigour and fertility to the offspring. But we have seen that greater changes, or changes of a particular nature, often render organic beings in some degree sterile; and that greater crosses, that is crosses between males and females which have become widely or specifically different, produce hybrids which are generally sterile in some degree. I cannot persuade myself that this parallelism is an accident or an illusion. Both series of facts seem to be connected together by some common but unknown bond, which is essentially related to the principle of life.

Fertility of Varieties when crossed, and of their Mongrel off-spring. It may be urged, as a most forcible argument, that there must be some essential distinction between species and varieties, and that there must be some error in all the foregoing remarks, inasmuch as varieties, however much they may differ from each other in external appearance, cross with perfect facility, and yield perfectly fertile offspring. I fully admit that this is almost invariably the case. But if we look to varieties produced under nature, we are immediately involved in hopeless difficulties; for if two hitherto reputed varieties be found in any degree sterile together, they are at once ranked by most naturalists as species. For instance, the blue and red pimpernel, the primrose and cowslip, which are considered by many of our best botanists as varieties, are said by Gärtner not to be quite fertile when crossed, and he consequently ranks them as undoubted species. If we thus argue in a circle, the fertility of all varieties produced under nature will assuredly have to be granted.

If we turn to varieties, produced, or supposed to have been produced, under domestication, we are still involved in doubt. For when it is stated, for instance, that the German Spitz dog unites more easily than other dogs with foxes, or that certain South American indigenous domestic dogs do not readily cross with European dogs, the explanation which will occur to everyone, and probably the true one, is that these dogs have descended from several aboriginally distinct species. Nevertheless the perfect fertility of so many domestic varieties, differing widely from each other in appearance, for instance of the pigeon or of the cabbage, is a remarkable fact; more especially when we reflect how many species there are, which, though resembling each other most closely, are utterly sterile when intercrossed. Several considerations, however, render the fertility of domestic varieties less remarkable than at first appears. It can, in the first place, be clearly shown that mere external dissimilarity between two species does not determine their greater or lesser degree of sterility when crossed; and we may apply the same rule to domestic varieties. In the second place, some eminent naturalists believe that a long course of domestication tends to eliminate sterility in the successive generations of hybrids, which were at first only slightly sterile; and if this be so, we surely ought not to expect to find sterility both appearing and disappearing under nearly the same conditions of life. Lastly, and this seems to me by far the most important consideration, new races of animals and plants are produced under domestication by man's methodical and unconscious power of selection, for his own use and pleasure: he neither wishes to select, nor could select, slight differences in the reproductive system, or other constitutional difference correlated with the reproductive system. He supplies his several varieties with the same food; treats them in nearly the same manner, and does not wish to alter their general habits of life. Nature acts uniformly and slowly during vast periods of time on the whole organization, in any way which may be for each creature's own good; and thus she may, either directly, or more probably indirectly, through correlation, modify the reproductive system in the several descendants from any one species. Seeing this difference in the process of selection, as carried on by man and nature, we need not be surprised at some difference in the result.

I have as yet spoken as if the varieties of the same species were invariably fertile when intercrossed. But it seems to me impossible to resist the evidence of the existence of a certain amount of sterility in the few following cases, which I will briefly abstract. The evidence is at least as good as that from which we believe in the sterility of a multitude of species. The evidence is, also, derived from hostile witnesses, who in all other cases consider fertility and sterility as safe criterions of specific distinction. Gärtner kept during several years a dwarf kind of maize with yellow seeds, and a tall variety with red seeds, growing near each other in his garden; and although these plants have separated sexes, they never naturally crossed. He then fertilized thirteen flowers of the one with the pollen of the other; but only a single head produced any seed, and this one head produced only five grains. Manipulation in this case could not have been injurious, as the plants have separated sexes. No one, I believe, has suspected that these varieties of maize are distinct species; and it is important to notice that the hybrid plants thus raised were themselves perfectly fertile; so that even Gärtner did not venture to consider the two varieties as specifically distinct.

Girou de Buzareingues crossed three varieties of gourd, which like the maize has separated sexes, and he asserts that their mutual fertilization is by so much the less easy as their differences are greater. How far these experiments may be trusted, I know not; but the forms experimentised on, are ranked by Sagaret, who mainly founds his classification by the test of infertility, as varieties.

The following case is far more remarkable, and seems at first quite incredible; but it is the result of an astonishing number of experiments made during many years on nine species of Verbascum, by so good an observer and so hostile a witness, as Gärtner: namely, that yellow and white varieties of the same species of Verbascum when intercrossed produce less seed, than do either coloured varieties when fertilized with pollen from their own coloured flowers. Moreover, he asserts that when yellow and white varieties of one species are crossed with yellow and white varieties of a distinct species, more seed is produced by the crosses between the same coloured flowers, than between those which are differently coloured. Yet these varieties of Verbascum present no other difference besides the mere colour of the flower; and one variety can sometimes be raised from the seed of the other.

From observations which I have made on certain varieties of hollyhock, I am inclined to suspect that they present analogous facts.

Kölreuter, whose accuracy has been confirmed by every subsequent observer, has proved the remarkable fact, that one variety of the common tobacco is more fertile, when crossed with a widely distinct species, than are the other varieties. He experimentised on five forms, which are commonly reputed to be varieties, and which he tested by the severest trial, namely, by reciprocal crosses, and he found their mongrel offspring perfectly fertile. But one of these five varieties, when used either as father or mother, and crossed with the Nicotiana glutinosa, always yielded hybrids not so sterile as those which were produced from the four other varieties when crossed with N. glutinosa. Hence the reproductive system of this one variety must have been in some manner and in some degree modified.

From these facts; from the great difficulty of ascertaining the infertility of varieties in a state of nature, for a supposed variety if infertile in any degree would generally be ranked as species; from man selecting only external characters in the production of the most distinct domestic varieties, and from not wishing or being able to produce recondite and functional differences in the reproductive system; from these several considerations and facts, I do not think that the very general fertility of varieties can be proved to be of universal occurrence, or to form a fundamental distinction between varieties and species. The general fertility of varieties does not seem to me sufficient to overthrow the view which I have taken with respect to the very general, but not invariable, sterility of first crosses and of hybrids, namely, that it is not a special endowment, but is incidental on slowly acquired modifications, more especially in the reproductive systems of the forms which are crossed.

Hybrids and Mongrels compared, independently of their fertility. Independently of the question of fertility, the offspring of species when crossed and of varieties when crossed may be compared in several other respects. Gärtner, whose strong wish was to draw a marked line of distinction between species and varieties, could find very few and, as it seems to me, quite unimportant differences between the so-called hybrid offspring of species, and the so-called mongrel offspring of varieties. And, on the other hand, they agree most closely in very many important respects.

I shall here discuss this subject with extreme brevity. The most important distinction is, that in the first generation mongrels are more variable than hybrids; but Gärtner admits that hybrids from species which have long been cultivated are often variable in the first generation; and I have myself seen striking instances of this fact. Gärtner further admits that hybrids between very closely allied species are more variable than those from very distinct species; and this shows that the difference in the degree of variability graduates away. When mongrels and the more fertile hybrids are propagated for several generations an extreme amount of variability in their offspring is notorious; but some few cases both of hybrids and mongrels long retaining uniformity of character could be given. The variability, however, in the successive generations of mongrels is, perhaps, greater than in hybrids.

This greater variability of mongrels than of hybrids does not seem to me at all surprising. For the parents of mongrels are varieties, and mostly domestic varieties (very few experiments having been tried on natural varieties), and this implies in most cases that there has been recent variability; and therefore we might expect that such variability would often continue and be super-added to that arising from the mere act of crossing. The slight degree of variability in hybrids from the first cross or in the first generation, in contrast with their extreme variability in the succeeding generations, is a curious fact and deserves attention. For it bears on and corroborates the view which I have taken on the cause of ordinary variability; namely, that it is due to the reproductive system being eminently sensitive to any change in the conditions of life, being thus often rendered either impotent or at least incapable of its proper function of producing offspring identical with the parent-form. Now hybrids in the first generation are descended from species (excluding those long cultivated) which have not had their reproductive systems in any way affected, and they are not variable; but hybrids themselves have their reproductive systems seriously affected, and their descendants are highly variable.

But to return to our comparison of mongrels and hybrids: Gärtner states that mongrels are more liable than hybrids to revert to either parent-form; but this, if it be true, is certainly only a difference in degree. Gärtner further insists that when any two species, although most closely allied to each other, are crossed with a third species, the hybrids are widely different from each other; whereas if two very distinct varieties of one species are crossed with another species, the hybrids do not differ much. But this conclusion, as far as I can make out, is founded on a single experiment; and seems directly opposed to the results of several experiments made by Kölreuter.

These alone are the unimportant differences, which Gärtner is able to point out, between hybrid and mongrel plants. On the other hand, the resemblance in mongrels and in hybrids to their respective parents, more especially in hybrids produced from nearly related species, follows according to Gärtner the same laws. When two species are crossed, one has sometimes a prepotent power of impressing its likeness on the hybrid; and so I believe it to be with varieties of plants. With animals one variety certainly often has this prepotent power over another variety. Hybrid plants produced from a reciprocal cross, generally resemble each other closely; and so it is with mongrels from a reciprocal cross. Both hybrids and mongrels can be reduced to either pure parent-form, by repeated crosses in successive generations with either parent.

These several remarks are apparently applicable to animals; but the subject is here excessively complicated, partly owing to the existence of secondary sexual characters; but more especially owing to prepotency in transmitting likeness running more strongly in one sex than in the other, both when one species is crossed with another, and when one variety is crossed with another variety. For instance, I think those authors are right, who maintain that the ass has a prepotent power over the horse, so that both the mule and the hinny more resemble the ass than the horse; but that the prepotency runs more strongly in the male-ass than in the female, so that the mule, which is the offspring of the male-ass and mare, is more like an ass, than is the hinny, which is the offspring of the female-ass and stallion.

Much stress has been laid by some authors on the supposed fact, that mongrel animals alone are born closely like one of their parents; but it can be shown that this does sometimes occur with hybrids; yet I grant much less frequently with hybrids than with mongrels. Looking to the cases which I have collected of cross-bred animals closely resembling one parent, the resemblances seem chiefly confined to characters almost monstrous in their nature, and which have suddenly appeared such as albinism, melanism, deficiency of tail or horns, or additional fingers and toes; and do not relate to characters which have been slowly acquired by selection. Consequently, sudden reversions to the perfect character of either parent would be more likely to occur with mongrels, which are descended from varieties often suddenly produced and semi-monstrous in character, than with hybrids, which are descended from species slowly and naturally produced. On the whole I entirely agree with Dr Prosper Lucas, who, after arranging an enormous body of facts with respect to animals, comes to the conclusion, that the laws of resemblance of the child to its parents are the same, whether the two parents differ much or little from each other, namely in the union of individuals of the same variety, or of different varieties, or of distinct species.

Laying aside the question of fertility and sterility, in all other respects there seems to be a general and close similarity in the offspring of crossed species, and of crossed varieties. If we look at species as having been specially created, and at varieties as having been produced by secondary laws, this similarity would be an astonishing fact. But it harmonizes perfectly with the view that there is no essential distinction between species and varieties.

Summary of Chapter. First crosses between forms sufficiently distinct to be ranked as species, and their hybrids, are very generally, but not universally, sterile. The sterility is of all degrees, and is often so slight that the two most careful experimentalists who have ever lived, have come to diametrically opposite conclusions in ranking forms by this test. The sterility is innately variable in individuals of the same species, and is eminently susceptible of favourable and unfavourable conditions. The degree of sterility does not strictly follow systematic affinity, but is governed by several curious and complex laws. It is generally different, and sometimes widely different, in reciprocal crosses between the same two species. It is not always equal in degree in a first cross and in the hybrid produced from this cross.

In the same manner as in grafting trees, the capacity of one species or variety to take on another, is incidental on generally unknown differences in their vegetative systems, so in crossing, the greater or less facility of one species to unite with another, is incidental on unknown differences in their reproductive systems. There is no more reason to think that species have been specially endowed with various degrees of sterility to prevent them crossing and blending in nature, than to think that trees have been specially endowed with various and somewhat analogous degrees of difficulty in being grafted together in order to prevent them becoming inarched in our forests.

The sterility of first crosses between pure species, which have their reproductive systems perfect, seems to depend on several circumstances; in some cases largely on the early death of the embryo. The sterility of hybrids, which have their reproductive systems imperfect, and which have had this system and their whole organisation disturbed by being compounded of two distinct species, seems closely allied to that sterility which so frequently affects pure species, when their natural conditions of life have been disturbed. This view is supported by a parallelism of another kind; namely, that the crossing of forms only slightly different is favourable to the vigour and fertility of their offspring; and that slight changes in the conditions of life are apparently favourable to the vigour and fertility of all organic beings. It is not surprising that the degree of difficulty in uniting two species, and the degree of sterility of their hybrid-offspring should generally correspond, though due to distinct causes; for both depend on the amount of difference of some kind between the species which are crossed. Nor is it surprising that the facility of effecting a first cross, the fertility of the hybrids produced, and the capacity of being grafted together though this latter capacity evidently depends on widely different circumstances should all run, to a certain extent, parallel with the systematic affinity of the forms which are subjected to experiment; for systematic affinity attempts to express all kinds of resemblance between all species.

First crosses between forms known to be varieties, or sufficiently alike to be considered as varieties, and their mongrel offspring, are very generally, but not quite universally, fertile. Nor is this nearly general and perfect fertility surprising, when we remember how liable we are to argue in a circle with respect to varieties in a state of nature; and when we remember that the greater number of varieties have been produced under domestication by the selection of mere external differences, and not of differences in the reproductive system. In all other respects, excluding fertility, there is a close general resemblance between hybrids and mongrels. Finally, then, the facts briefly given in this chapter do not seem to me opposed to, but even rather to support the view, that there is no fundamental distinction between species and varieties. 

N the sixth chapter I enumerated the chief objections which might be justly urged against the views maintained in this volume. Most of them have now been discussed. One, namely the distinctness of specific forms, and their not being blended together by innumerable transitional links, is a very obvious difficulty. I assigned reasons why such links do not commonly occur at the present day, under the circumstances apparently most favourable for their presence, namely on an extensive and continuous area with graduated physical conditions. I endeavoured to show, that the life of each species depends in a more important manner on the presence of other already defined organic forms, than on climate; and, therefore, that the really governing conditions of life do not graduate away quite insensibly like heat or moisture. I endeavoured, also, to show that intermediate varieties, from existing in lesser numbers than the forms which they connect, will generally be beaten out and exterminated during the course of further modification and improvement. The main cause, however, of innumerable intermediate links not now occurring everywhere throughout nature depends on the very process of natural selection, through which new varieties continually take the places of and exterminate their parent-forms. But just in proportion as this process of extermination has acted on an enormous scale, so must the number of intermediate varieties, which have formerly existed on the earth, be truly enormous. Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and gravest objection which can be urged against my theory. The explanation lies, as I believe, in the extreme imperfection of the geological record.

In the first place it should always be borne in mind what sort of intermediate forms must, on my theory, have formerly existed. I have found it difficult, when looking at any two species, to avoid picturing to myself, forms directly intermediate between them. But this is a wholly false view; we should always look for forms intermediate between each species and a common but unknown progenitor; and the progenitor will generally have differed in some respects from all its modified descendants. To give a simple illustration: the fantail and pouter pigeons have both descended from the rock-pigeon; if we possessed all the intermediate varieties which have ever existed, we should have an extremely close series between both and the rock-pigeon; but we should have no varieties directly intermediate between the fantail and pouter; none, for instance, combining a tail somewhat expanded with a crop somewhat enlarged, the characteristic features of these two breeds. These two breeds, moreover, have become so much modified, that if we had no historical or indirect evidence regarding their origin, it would not have been possible to have determined from a mere comparison of their structure with that of the rock-pigeon, whether they had descended from this species or from some other allied species, such as C. oenas.

So with natural species, if we look to forms very distinct, for instance to the horse and tapir, we have no reason to suppose that links ever existed directly intermediate between them, but between each and an unknown common parent. The common parent will have had in its whole organisation much general resemblance to the tapir and to the horse; but in some points of structure may have differed considerably from both, even perhaps more than they differ from each other. Hence in all such cases, we should be unable to recognise the parent-form of any two or more species, even if we closely compared the structure of the parent with that of its modified descendants, unless at the same time we had a nearly perfect chain of the intermediate links.

It is just possible by my theory, that one of two living forms might have descended from the other; for instance, a horse from a tapir; and in this case direct intermediate links will have existed between them. But such a case would imply that one form had remained for a very long period unaltered, whilst its descendants had undergone a vast amount of change; and the principle of competition between organism and organism, between child and parent, will render this a very rare event; for in all cases the new and improved forms of life will tend to supplant the old and unimproved.

By the theory of natural selection all living species have been connected with the parent-species of each genus, by differences not greater than we see between the varieties of the same species at the present day; and these parent-species, now generally extinct, have in their turn been similarly connected with more ancient species; and so on backwards, always converging to the common ancestor of each great class. So that the number of intermediate and transitional links, between all living and extinct species, must have been inconceivably great. But assuredly, if this theory be true, such have lived upon this earth.

On the lapse of Time. Independently of our not finding fossil remains of such infinitely numerous connecting links, it may be objected, that time will not have sufficed for so great an amount of organic change, all changes having been effected very slowly through natural selection. It is hardly possible for me even to recall to the reader, who may not be a practical geologist, the facts leading the mind feebly to comprehend the lapse of time. He who can read Sir Charles Lyell's grand work on the Principles of Geology, which the future historian will recognise as having produced a revolution in natural science, yet does not admit how incomprehensibly vast have been the past periods of time, may at once close this volume. Not that it suffices to study the Principles of Geology, or to read special treatises by different observers on separate formations, and to mark how each author attempts to give an inadequate idea of the duration of each formation or even each stratum. A man must for years examine for himself great piles of superimposed strata, and watch the sea at work grinding down old rocks and making fresh sediment, before he can hope to comprehend anything of the lapse of time, the monuments of which we see around us.

It is good to wander along lines of sea-coast, when formed of moderately hard rocks, and mark the process of degradation. The tides in most cases reach the cliffs only for a short time twice a day, and the waves eat into them only when they are charged with sand or pebbles; for there is reason to believe that pure water can effect little or nothing in wearing away rock. At last the base of the cliff is undermined, huge fragments fall down, and these remaining fixed, have to be worn away, atom by atom, until reduced in size they can be rolled about by the waves, and then are more quickly ground into pebbles, sand, or mud. But how often do we see along the bases of retreating cliffs rounded boulders, all thickly clothed by marine productions, showing how little they are abraded and how seldom they are rolled about! Moreover, if we follow for a few miles any line of rocky cliff, which is undergoing degradation, we find that it is only here and there, along a short length or round a promontory, that the cliffs are at the present time suffering. The appearance of the surface and the vegetation show that elsewhere years have elapsed since the waters washed their base.

He who most closely studies the action of the sea on our shores, will, I believe, be most deeply impressed with the slowness with which rocky coasts are worn away. The observations on this head by Hugh Miller, and by that excellent observer Mr. Smith of Jordan Hill, are most impressive. With the mind thus impressed, let any one examine beds of conglomerate many thousand feet in thickness, which, though probably formed at a quicker rate than many other deposits, yet, from being formed of worn and rounded pebbles, each of which bears the stamp of time, are good to show how slowly the mass has been accumulated. Let him remember Lyell's profound remark, that the thickness and extent of sedimentary formations are the result and measure of the degradation which the earth's crust has elsewhere suffered. And what an amount of degradation is implied by the sedimentary deposits of many countries! Professor Ramsay has given me the maximum thickness, in most cases from actual measurement, in a few cases from estimate, of each formation in different parts of Great Britain; and this is the result:-

Feet

Palaeozoic strata (not including igneous beds) 57,154

Secondary strata 13,190

Tertiary strata 2,240

making altogether 72,584 feet; that is, very nearly thirteen and three-quarters British miles. Some of these formations, which are represented in England by thin beds, are thousands of feet in thickness on the Continent. Moreover, between each successive formation, we have, in the opinion of most geologists, enormously long blank periods. So that the lofty pile of sedimentary rocks in Britain, gives but an inadequate idea of the time which has elapsed during their accumulation; yet what time this must have consumed! Good observers have estimated that sediment is deposited by the great Mississippi river at the rate of only 600 feet in a hundred thousand years. This estimate may be quite erroneous; yet, considering over what wide spaces very fine sediment is transported by the currents of the sea, the process of accumulation in any one area must be extremely slow.

But the amount of denudation which the strata have in many places suffered, independently of the rate of accumulation of the degraded matter, probably offers the best evidence of the lapse of time. I remember having been much struck with the evidence of denudation, when viewing volcanic islands, which have been worn by the waves and pared all round into perpendicular cliffs of one or two thousand feet in height; for the gentle slope of the lava-streams, due to their formerly liquid state, showed at a glance how far the hard, rocky beds had once extended into the open ocean. The same story is still more plainly told by faults, those great cracks along which the strata have been upheaved on one side, or thrown down on the other, to the height or depth of thousands of feet; for since the crust cracked, the surface of the land has been so completely planed down by the action of the sea, that no trace of these vast dislocations is externally visible.

The Craven fault, for instance, extends for upwards of 30 miles, and along this line the vertical displacement of the strata has varied from 600 to 3000 feet. Prof. Ramsay has published an account of a downthrow in Anglesea of 2300 feet; and he informs me that he fully believes there is one in Merionethshire of 12,000 feet; yet in these cases there is nothing on the surface to show such prodigious movements; the pile of rocks on the one or other side having been smoothly swept away. The consideration of these facts impresses my mind almost in the same manner as does the vain endeavour to grapple with the idea of eternity.

I am tempted to give one other case, the well-known one of the denudation of the Weald. Though it must be admitted that the denudation of the Weald has been a mere trifle, in comparison with that which has removed masses of our Palaeozoic strata, in parts ten thousand feet in thickness, as shown in Prof. Ramsay's masterly memoir on this subject. Yet it is an admirable lesson to stand on the North Downs and to look at the distant South Downs; for, remembering that at no great distance to the west the northern and southern escarpments meet and close, one can safely picture to oneself the great dome of rocks which must have covered up the Weald within so limited a period as since the latter part of the Chalk formation. The distance from the northern to the southern Downs is about 22 miles, and the thickness of the several formations is on an average about 1100 feet, as I am informed by Prof. Ramsay. But if, as some geologists suppose, a range of older rocks underlies the Weald, on the flanks of which the overlying sedimentary deposits might have accumulated in thinner masses than elsewhere, the above estimate would be erroneous; but this source of doubt probably would not greatly affect the estimate as applied to the western extremity of the district. If, then, we knew the rate at which the sea commonly wears away a line of cliff of any given height, we could measure the time requisite to have denuded the Weald. This, of course, cannot be done; but we may, in order to form some crude notion on the subject, assume that the sea would eat into cliffs 500 feet in height at the rate of one inch in a century. This will at first appear much too small an allowance; but it is the same as if we were to assume a cliff one yard in height to be eaten back along a whole line of coast at the rate of one yard in nearly every twenty-two years. I doubt whether any rock, even as soft as chalk, would yield at this rate excepting on the most exposed coasts; though no doubt the degradation of a lofty cliff would be more rapid from the breakage of the fallen fragments. On the other hand, I do not believe that any line of coast, ten or twenty miles in length, ever suffers degradation at the same time along its whole indented length; and we must remember that almost all strata contain harder layers or nodules, which from long resisting attrition form a breakwater at the base. Hence, under ordinary circumstances, I conclude that for a cliff 500 feet in height, a denudation of one inch per century for the whole length would be an ample allowance. At this rate, on the above data, the denudation of the Weald must have required 306,662,400 years; or say three hundred million years.

The action of fresh water on the gently inclined Wealden district, when upraised, could hardly have been great, but it would somewhat reduce the above estimate. On the other hand, during oscillations of level, which we know this area has undergone, the surface may have existed for millions of years as land, and thus have escaped the action of the sea: when deeply submerged for perhaps equally long periods, it would, likewise, have escaped the action of the coast-waves. So that in all probability a far longer period than 300 million years has elapsed since the latter part of the Secondary period.

I have made these few remarks because it is highly important for us to gain some notion, however imperfect, of the lapse of years. During each of these years, over the whole world, the land and the water has been peopled by hosts of living forms. What an infinite number of generations, which the mind cannot grasp, must have succeeded each other in the long roll of years! Now turn to our richest geological museums, and what a paltry display we behold!

On the poorness of our Palaeontological collections. That our Palaeontological collections are very imperfect, is admitted by every one. The remark of that admirable Palaeontologist, the late Edward Forbes, should not be forgotten, namely, that numbers of our fossil species are known and named from single and often broken specimens, or from a few specimens collected on some one spot. Only a small portion of the surface of the earth has been geologically explored, and no part with sufficient care, as the important discoveries made every year in Europe prove. No organism wholly soft can be preserved. Shells and bones will decay and disappear when left on the bottom of the sea, where sediment is not accumulating. I believe we are continually taking a most erroneous view, when we tacitly admit to ourselves that sediment is being deposited over nearly the whole bed of the sea, at a rate sufficiently quick to embed and preserve fossil remains. Throughout an enormously large proportion of the ocean, the bright blue tint of the water bespeaks its purity. The many cases on record of a formation conformably covered, after an enormous interval of time, by another and later formation, without the underlying bed having suffered in the interval any wear and tear, seem explicable only on the view of the bottom of the sea not rarely lying for ages in an unaltered condition. The remains which do become embedded, if in sand or gravel, will when the beds are upraised generally be dissolved by the percolation of rain-water. I suspect that but few of the very many animals which live on the beach between high and low watermark are preserved. For instance, the several species of the Chthamalinae (a sub-family of sessile cirripedes) coat the rocks all over the world in infinite numbers: they are all strictly littoral, with the exception of a single Mediterranean species, which inhabits deep water and has been found fossil in Sicily, whereas not one other species has hitherto been found in any tertiary formation: yet it is now known that the genus Chthamalus existed during the chalk period. The molluscan genus Chiton offers a partially analogous case.

With respect to the terrestrial productions which lived during the Secondary and Palaeozoic periods, it is superfluous to state that our evidence from fossil remains is fragmentary in an extreme degree. For instance, not a land shell is known belonging to either of these vast periods, with one exception discovered by Sir C. Lyell in the carboniferous strata of North America. I n regard to mammiferous remains, a single glance at the historical table published in the Supplement to Lyell's Manual, will bring home the truth, how accidental and rare is their preservation, far better than pages of detail. Nor is their rarity surprising, when we remember how large a proportion of the bones of tertiary mammals have been discovered either in caves or in lacustrine deposits; and that not a cave or true lacustrine bed is known belonging to the age of our secondary or palaeozoic formations.

But the imperfection in the geological record mainly results from another and more important cause than any of the foregoing; namely, from the several formations being separated from each other by wide intervals of time. When we see the formations tabulated in written works, or when we follow them in nature, it is difficult to avoid believing that they are closely consecutive. But we know, for instance, from Sir R. Murchison's great work on Russia, what wide gaps there are in that country between the superimposed formations; so it is in North America, and in many other parts of the world. The most skilful geologist, if his attention had been exclusively confined to these large territories, would never have suspected that during the periods which were blank and barren in his own country, great piles of sediment, charged with new and peculiar forms of life, had elsewhere been accumulated. And if in each separate territory, hardly any idea can be formed of the length of time which has elapsed between the consecutive formations, we may infer that this could nowhere be ascertained. The frequent and great changes in the mineralogical composition of consecutive formations, generally implying great changes in the geography of the surrounding lands, whence the sediment has been derived, accords with the belief of vast intervals of time having elapsed between each formation.

But we can, I think, see why the geological formations of each region are almost invariably intermittent; that is, have not followed each other in close sequence. Scarcely any fact struck me more when examining many hundred miles of the South American coasts, which have been upraised several hundred feet within the recent period, than the absence of any recent deposits sufficiently extensive to last for even a short geological period. Along the whole west coast, which is inhabited by a peculiar marine fauna, tertiary beds are so scantily developed, that no record of several successive and peculiar marine faunas will probably be preserved to a distant age. A little reflection will explain why along the rising coast of the western side of South America, no extensive formations with recent or tertiary remains can anywhere be found, though the supply of sediment must for ages have been great, from the enormous degradation of the coast-rocks and from muddy streams entering the sea. The explanation, no doubt, is, that the littoral and sub-littoral deposits are continually worn away, as soon as they are brought up by the slow and gradual rising of the land within the grinding action of the coast-waves.

We may, I think, safely conclude that sediment must be accumulated in extremely thick, solid, or extensive masses, in order to withstand the incessant action of the waves, when first upraised and during subsequent oscillations of level. Such thick and extensive accumulations of sediment may be formed in two ways; either, in profound depths of the sea, in which case, judging from the researches of E. Forbes, we may conclude that the bottom will be inhabited by extremely few animals, and the mass when upraised will give a most imperfect record of the forms of life which then existed; or, sediment may be accumulated to any thickness and extent over a shallow bottom, if it continue slowly to subside. In this latter case, as long as the rate of subsidence and supply of sediment nearly balance each other, the sea will remain shallow and favourable for life, and thus a fossiliferous formation thick enough, when upraised, to resist any amount of degradation, may be formed.

I am convinced that all our ancient formations, which are rich in fossils, have thus been formed during subsidence. Since publishing my views on this subject in 1845, I have watched the progress of Geology, and have been surprised to note how author after author, in treating of this or that great formation, has come to the conclusion that it was accumulated during subsidence. I may add, that the only ancient tertiary formation on the west coast of South America, which has been bulky enough to resist such degradation as it has as yet suffered, but which will hardly last to a distant geological age, was certainly deposited during a downward oscillation of level, and thus gained considerable thickness.

All geological facts tell us plainly that each area has undergone numerous slow oscillations of level, and apparently these oscillations have affected wide spaces. Consequently formations rich in fossils and sufficiently thick and extensive to resist subsequent degradation, may have been formed over wide spaces during periods of subsidence, but only where the supply of sediment was sufficient to keep the sea shallow and to embed and preserve the remains before they had time to decay. On the other hand, as long as the bed of the sea remained stationary, thick deposits could not have been accumulated in the shallow parts, which are the most favourable to life. Still less could this have happened during the alternate periods of elevation; or, to speak more accurately, the beds which were then accumulated will have been destroyed by being upraised and brought within the limits of the coast-action.

Thus the geological record will almost necessarily be rendered intermittent. I feel much confidence in the truth of these views, for they are in strict accordance with the general principles inculcated by Sir C. Lyell; and E. Forbes independently arrived at a similar conclusion.

One remark is here worth a passing notice. During periods of elevation the area of the land and of the adjoining shoal parts of the sea will be increased, and new stations will often be formed; all circumstances most favourable, as previously explained, for the formation of new varieties and species; but during such periods there will generally be a blank in the geological record. On the other hand, during subsidence, the inhabited area and number of inhabitants will decrease (excepting the productions on the shores of a continent when first broken up into an archipelago), and consequently during subsidence, though there will be much extinction, fewer new varieties or species will be formed; and it is during these very periods of subsidence, that our great deposits rich in fossils have been accumulated. Nature may almost be said to have guarded against the frequent discovery of her transitional or linking forms.

From the foregoing considerations it cannot be doubted that the geological record, viewed as a whole, is extremely imperfect; but if we confine our attention to any one formation, it becomes more difficult to understand, why we do not therein find closely graduated varieties between the allied species which lived at its commencement and at its close. Some cases are on record of the same species presenting distinct varieties in the upper and lower parts of the same formation, but, as they are rare, they may be here passed over. Although each formation has indisputably required a vast number of years for its deposition, I can see several reasons why each should not include a graduated series of links between the species which then lived; but I can by no means pretend to assign due proportional weight to the following considerations.

Although each formation may mark a very long lapse of years, each perhaps is short compared with the period requisite to change one species into another. I am aware that two palaeontologists, whose opinions are worthy of much deference, namely Bronn and Woodward, have concluded that the average duration of each formation is twice or thrice as long as the average duration of specific forms. But insuperable difficulties, as it seems to me, prevent us coming to any just conclusion on this head. When we see a species first appearing in the middle of any formation, it would be rash in the extreme to infer that it had not elsewhere previously existed. So again when we find a species disappearing before the uppermost layers have been deposited, it would be equally rash to suppose that it then became wholly extinct. We forget how small the area of Europe is compared with the rest of the world; nor have the several stages of the same formation throughout Europe been correlated with perfect accuracy.

With marine animals of all kinds, we may safely infer a large amount of migration during climatal and other changes; and when we see a species first appearing in any formation, the probability is that it only then first immigrated into that area. It is well known, for instance, that several species appeared somewhat earlier in the palaeozoic beds of North America than in those of Europe; time having apparently been required for their migration from the American to the European seas. In examining the latest deposits of various quarters of the world, it has everywhere been noted, that some few still existing species are common in the deposit, but have become extinct in the immediately surrounding sea; or, conversely, that some are now abundant in the neighbouring sea, but are rare or absent in this particular deposit. It is an excellent lesson to reflect on the ascertained amount of migration of the inhabitants of Europe during the Glacial period, which forms only a part of one whole geological period; and likewise to reflect on the great changes of level, on the inordinately great change of climate, on the prodigious lapse of time, all included within this same glacial period. Yet it may be doubted whether in any quarter of the world, sedimentary deposits, including fossil remains, have gone on accumulating within the same area during the whole of this period. It is not, for instance, probable that sediment was deposited during the whole of the glacial period near the mouth of the Mississippi, within that limit of depth at which marine animals can flourish; for we know what vast geographical changes occurred in other parts of America during this space of time. When such beds as were deposited in shallow water near the mouth of the Mississippi during some part of the glacial period shall have been upraised, organic remains will probably first appear and disappear at different levels, owing to the migration of species and to geographical changes. And in the distant future, a geologist examining these beds, might be tempted to conclude that the average duration of life of the embedded fossils had been less than that of the glacial period, instead of having been really far greater, that is extending from before the glacial epoch to the present day.

In order to get a perfect gradation between two forms in the upper and lower parts of the same formation, the deposit must have gone on accumulating for a very long period, in order to have given sufficient time for the slow process of variation; hence the deposit will generally have to be a very thick one; and the species undergoing modification will have had to live on the same area throughout this whole time. But we have seen that a thick fossiliferous formation can only be accumulated during a period of subsidence; and to keep the depth approximately the same, which is necessary in order to enable the same species to live on the same space, the supply of sediment must nearly have counterbalanced the amount of subsidence. But this same movement of subsidence will often tend to sink the area whence the sediment is derived, and thus diminish the supply whilst the downward movement continues. In fact, this nearly exact balancing between the supply of sediment and the amount of subsidence is probably a rare contingency; for it has been observed by more than one palaeontologist, that very thick deposits are usually barren of organic remains, except near their upper or lower limits.

It would seem that each separate formation, like the whole pile of formations in any country, has generally been intermittent in its accumulation. When we see, as is so often the case, a formation composed of beds of different mineralogical composition, we may reasonably suspect that the process of deposition has been much interrupted, as a change in the currents of the sea and a supply of sediment of a different nature will generally have been due to geographical changes requiring much time. Nor will the closest inspection of a formation give any idea of the time which its deposition has consumed. Many instances could be given of beds only a few feet in thickness, representing formations, elsewhere thousands of feet in thickness, and which must have required an enormous period for their accumulation; yet no one ignorant of this fact would have suspected the vast lapse of time represented by the thinner formation. Many cases could be given of the lower beds of a formation having been upraised, denuded, submerged, and then re-covered by the upper beds of the same formation, facts, showing what wide, yet easily overlooked, intervals have occurred in its accumulation. In other cases we have the plainest evidence in great fossilised trees, still standing upright as they grew, of many long intervals of time and changes of level during the process of deposition, which would never even have been suspected, had not the trees chanced to have been preserved: thus, Messrs Lyell and Dawson found carboniferous beds 1400 feet thick in Nova Scotia, with ancient root-bearing strata, one above the other, at no less than sixty-eight different levels. Hence, when the same species occur at the bottom, middle, and top of a formation, the probability is that they have not lived on the same spot during the whole period of deposition, but have disappeared and reappeared, perhaps many times, during the same geological period. So that if such species were to undergo a considerable amount of modification during any one geological period, a section would not probably include all the fine intermediate gradations which must on my theory have existed between them, but abrupt, though perhaps very slight, changes of form.

It is all-important to remember that naturalists have no golden rule by which to distinguish species and varieties; they grant some little variability to each species, but when they meet with a somewhat greater amount of difference between any two forms, they rank both as species, unless they are enabled to connect them together by close intermediate gradations. And this from the reasons just assigned we can seldom hope to effect in any one geological section. Supposing B and C to be two species, and a third, A, to be found in an underlying bed; even if A were strictly intermediate between B and C, it would simply be ranked as a third and distinct species, unless at the same time it could be most closely connected with either one or both forms by intermediate varieties. Nor should it be forgotten, as before explained, that A might be the actual progenitor of B and C, and yet might not at all necessarily be strictly intermediate between them in all points of structure. So that we might obtain the parent-species and its several modified descendants from the lower and upper beds of a formation, and unless we obtained numerous transitional gradations, we should not recognise their relationship, and should consequently be compelled to rank them all as distinct species.

It is notorious on what excessively slight differences many palaeontologists have founded their species; and they do this the more readily if the specimens come from different sub-stages of the same formation. Some experienced conchologists are now sinking many of the very fine species of D'Orbigny and others into the rank of varieties; and on this view we do find the kind of evidence of change which on my theory we ought to find. Moreover, if we look to rather wider intervals, namely, to distinct but consecutive stages of the same great formation, we find that the embedded fossils, though almost universally ranked as specifically different, yet are far more closely allied to each other than are the species found in more widely separated formations; but to this subject I shall have to return in the following chapter.

One other consideration is worth notice: with animals and plants that can propagate rapidly and are not highly locomotive, there is reason to suspect, as we have formerly seen, that their varieties are generally at first local; and that such local varieties do not spread widely and supplant their parent-forms until they have been modified and perfected in some considerable degree. According to this view, the chance of discovering in a formation in any one country all the early stages of transition between any two forms, is small, for the successive changes are supposed to have been local or confined to some one spot. Most marine animals have a wide range; and we have seen that with plants it is those which have the widest range, that oftenest present varieties; so that with shells and other marine animals, it is probably those which have had the widest range, far exceeding the limits of the known geological formations of Europe, which have oftenest given rise, first to local varieties and ultimately to new species; and this again would greatly lessen the chance of our being able to trace the stages of transition in any one geological formation.

It should not be forgotten, that at the present day, with perfect specimens for examination, two forms can seldom be connected by intermediate varieties and thus proved to be the same species, until many specimens have been collected from many places; and in the case of fossil species this could rarely be effected by palaeontologists. We shall, perhaps, best perceive the improbability of our being enabled to connect species by numerous, fine, intermediate, fossil links, by asking ourselves whether, for instance, geologists at some future period will be able to prove, that our different breeds of cattle, sheep, horses, and dogs have descended from a single stock or from several aboriginal stocks; or, again, whether certain sea-shells inhabiting the shores of North America, which are ranked by some conchologists as distinct species from their European representatives, and by other conchologists as only varieties, are really varieties or are, as it is called, specifically distinct. This could be effected only by the future geologist discovering in a fossil state numerous intermediate gradations; and such success seems to me improbable in the highest degree.

Geological research, though it has added numerous species to existing and extinct genera, and has made the intervals between some few groups less wide than they otherwise would have been, yet has done scarcely anything in breaking down the distinction between species, by connecting them together by numerous, fine, intermediate varieties; and this not having been effected, is probably the gravest and most obvious of all the many objections which may be urged against my views. Hence it will be worth while to sum up the foregoing remarks, under an imaginary illustration. The Malay Archipelago is of about the size of Europe from the North Cape to the Mediterranean, and from Britain to Russia; and therefore equals all the geological formations which have been examined with any accuracy, excepting those of the United States of America. I fully agree with Mr Godwin-Austen, that the present condition of the Malay Archipelago, with its numerous large islands separated by wide and shallow seas, probably represents the former state of Europe, when most of our formations were accumulating. The Malay Archipelago is one of the richest regions of the whole world in organic beings; yet if all the species were to be collected which have ever lived there, how imperfectly would they represent the natural history of the world!

But we have every reason to believe that the terrestrial productions of the archipelago would be preserved in an excessively imperfect manner in the formations which we suppose to be there accumulating. I suspect that not many of the strictly littoral animals, or of those which lived on naked submarine rocks, would be embedded; and those embedded in gravel or sand, would not endure to a distant epoch. Wherever sediment did not accumulate on the bed of the sea, or where it did not accumulate at a sufficient rate to protect organic bodies from decay, no remains could be preserved.

In our archipelago, I believe that fossiliferous formations could be formed of sufficient thickness to last to an age, as distant in futurity as the secondary formations lie in the past, only during periods of subsidence. These periods of subsidence would be separated from each other by enormous intervals, during which the area would be either stationary or rising; whilst rising, each fossiliferous formation would be destroyed, almost as soon as accumulated, by the incessant coast-action, as we now see on the shores of South America. During the periods of subsidence there would probably be much extinction of life; during the periods of elevation, there would be much variation, but the geological record would then be least perfect.

It may be doubted whether the duration of any one great period of subsidence over the whole or part of the archipelago, together with a contemporaneous accumulation of sediment, would exceed the average duration of the same specific forms; and these contingencies are indispensable for the preservation of all the transitional gradations between any two or more species. If such gradations were not fully preserved, transitional varieties would merely appear as so many distinct species. It is, also, probable that each great period of subsidence would be interrupted by oscillations of level, and that slight climatal changes would intervene during such lengthy periods; and in these cases the inhabitants of the archipelago would have to migrate, and no closely consecutive record of their modifications could be preserved in any one formation.

Very many of the marine inhabitants of the archipelago now range thousands of miles beyond its confines; and analogy leads me to believe that it would be chiefly these far-ranging species which would oftenest produce new varieties; and the varieties would at first generally be local or confined to one place, but if possessed of any decided advantage, or when further modified and improved, they would slowly spread and supplant their parent-forms. When such varieties returned to their ancient homes, as they would differ from their former state, in a nearly uniform, though perhaps extremely slight degree, they would, according to the principles followed by many palaeontologists, be ranked as new and distinct species.

If then, there be some degree of truth in these remarks, we have no right to expect to find in our geological formations, an infinite number of those fine transitional forms, which on my theory assuredly have connected all the past and present species of the same group into one long and branching chain of life. We ought only to look for a few links, some more closely, some more distantly related to each other; and these links, let them be ever so close, if found in different stages of the same formation, would, by most palaeontologists, be ranked as distinct species. But I do not pretend that I should ever have suspected how poor a record of the mutations of life, the best preserved geological section presented, had not the difficulty of our not discovering innumerable transitional links between the species which appeared at the commencement and close of each formation, pressed so hardly on my theory.

On the sudden appearance of whole groups of Allied Species. The abrupt manner in which whole groups of species suddenly appear in certain formations, has been urged by several palaeontologists, for instance, by Agassiz, Pictet, and by none more forcibly than by Professor Sedgwick, as a fatal objection to the belief in the transmutation of species. If numerous species, belonging to the same genera or families, have really started into life all at once, the fact would be fatal to the theory of descent with slow modification through natural selection. For the development of a group of forms, all of which have descended from some one progenitor, must have been an extremely slow process; and the progenitors must have lived long ages before their modified descendants. But we continually over-rate the perfection of the geological record, and falsely infer, because certain genera or families have not been found beneath a certain stage, that they did not exist before that stage. We continually forget how large the world is, compared with the area over which our geological formations have been carefully examined; we forget that groups of species may elsewhere have long existed and have slowly multiplied before they invaded the ancient archipelagoes of Europe and of the United States. We do not make due allowance for the enormous intervals of time, which have probably elapsed between our consecutive formations, longer perhaps in some cases than the time required for the accumulation of each formation. These intervals will have given time for the multiplication of species from some one or some few parent-forms; and in the succeeding formation such species will appear as if suddenly created.

I may here recall a remark formerly made, namely that it might require a long succession of ages to adapt an organism to some new and peculiar line of life, for instance to fly through the air; but that when this had been effected, and a few species had thus acquired a great advantage over other organisms, a comparatively short time would be necessary to produce many divergent forms, which would be able to spread rapidly and widely throughout the world.

I will now give a few examples to illustrate these remarks; and to show how liable we are to error in supposing that whole groups of species have suddenly been produced. I may recall the well-known fact that in geological treatises, published not many years ago, the great class of mammals was always spoken of as having abruptly come in at the commencement of the tertiary series. And now one of the richest known accumulations of fossil mammals belongs to the middle of the secondary series; and one true mammal has been discovered in the new red sandstone at nearly the commencement of this great series. Cuvier used to urge that no monkey occurred in any tertiary stratum; but now extinct species have been discovered in India, South America, and in Europe even as far back as the eocene stage. The most striking case, however, is that of the Whale family; as these animals have huge bones, are marine, and range over the world, the fact of not a single bone of a whale having been discovered in any secondary formation, seemed fully to justify the belief that this great and distinct order had been suddenly produced in the interval between the latest secondary and earliest tertiary formation. But now we may read in the Supplement to Lyell's 'Manual,' published in 1858, clear evidence of the existence of whales in the upper greensand, some time before the close of the secondary period.

I may give another instance, which from having passed under my own eyes has much struck me. In a memoir on Fossil Sessile Cirripedes, I have stated that, from the number of existing and extinct tertiary species; from the extraordinary abundance of the individuals of many species all over the world, from the Arctic regions to the equator, inhabiting various zones of depths from the upper tidal limits to 50 fathoms; from the perfect manner in which specimens are preserved in the oldest tertiary beds; from the ease with which even a fragment of a valve can be recognised; from all these circumstances, I inferred that had sessile cirripedes existed during the secondary periods, they would certainly have been preserved and discovered; and as not one species had been discovered in beds of this age, I concluded that this great group had been suddenly developed at the commencement of the tertiary series. This was a sore trouble to me, adding as I thought one more instance of the abrupt appearance of a great group of species. But my work had hardly been published, when a skilful palaeontologist, M. Bosquet, sent me a drawing of a perfect specimen of an unmistakeable sessile cirripede, which he had himself extracted from the chalk of Belgium. And, as if to make the case as striking as possible, this sessile cirripede was a Chthamalus, a very common, large, and ubiquitous genus, of which not one specimen has as yet been found even in any tertiary stratum. Hence we now positively know that sessile cirripedes existed during the secondary period; and these cirripedes might have been the progenitors of our many tertiary and existing species.

The case most frequently insisted on by palaeontologists of the apparently sudden appearance of a whole group of species, is that of the teleostean fishes, low down in the Chalk period. This group includes the large majority of existing species. Lately, Professor Pictet has carried their existence one sub-stage further back; and some palaeontologists believe that certain much older fishes, of which the affinities are as yet imperfectly known, are really teleostean. Assuming, however, that the whole of them did appear, as Agassiz believes, at the commencement of the chalk formation, the fact would certainly be highly remarkable; but I cannot see that it would be an insuperable difficulty on my theory, unless it could likewise be shown that the species of this group appeared suddenly and simultaneously throughout the world at this same period. It is almost superfluous to remark that hardly any fossil-fish are known from south of the equator; and by running through Pictet's palaeontology it will be seen that very few species are known from several formations in Europe. Some few families of fish now have a confined range; the teleostean fish might formerly have had a similarly confined range, and after having been largely developed in some one sea, might have spread widely. Nor have we any right to suppose that the seas of the world have always been so freely open from south to north as they are at present. Even at this day, if the Malay Archipelago were converted into land, the tropical parts of the Indian Ocean would form a large and perfectly enclosed basin, in which any great group of marine animals might be multiplied; and here they would remain confined, until some of the species became adapted to a cooler climate, and were enabled to double the southern capes of Africa or Australia, and thus reach other and distant seas.

From these and similar considerations, but chiefly from our ignorance of the geology of other countries beyond the confines of Europe and the United States; and from the revolution in our palaeontological ideas on many points, which the discoveries of even the last dozen years have effected, it seems to me to be about as rash in us to dogmatize on the succession of organic beings throughout the world, as it would be for a naturalist to land for five minutes on some one barren point in Australia, and then to discuss the number and range of its productions.

On the sudden appearance of groups of Allied Species in the lowest known fossiliferous strata. There is another and allied difficulty, which is much graver. I allude to the manner in which numbers of species of the same group, suddenly appear in the lowest known fossiliferous rocks. Most of the arguments which have convinced me that all the existing species of the same group have descended from one progenitor, apply with nearly equal force to the earliest known species. For instance, I cannot doubt that all the Silurian trilobites have descended from some one crustacean, which must have lived long before the Silurian age, and which probably differed greatly from any known animal. Some of the most ancient Silurian animals, as the Nautilus, Lingula, &c., do not differ much from living species; and it cannot on my theory be supposed, that these old species were the progenitors of all the species of the orders to which they belong, for they do not present characters in any degree intermediate between them. If, moreover, they had been the progenitors of these orders, they would almost certainly have been long ago supplanted and exterminated by their numerous and improved descendants.

Consequently, if my theory be true, it is indisputable that before the lowest Silurian stratum was deposited, long periods elapsed, as long as, or probably far longer than, the whole interval from the Silurian age to the present day; and that during these vast, yet quite unknown, periods of time, the world swarmed with living creatures.

To the question why we do not find records of these vast primordial periods, I can give no satisfactory answer. Several of the most eminent geologists, with Sir R. Murchison at their head, are convinced that we see in the organic remains of the lowest Silurian stratum the dawn of life on this planet. Other highly competent judges, as Lyell and the late E. Forbes, dispute this conclusion. We should not forget that only a small portion of the world is known with accuracy. M. Barrande has lately added another and lower stage to the Silurian system, abounding with new and peculiar species. Traces of life have been detected in the Longmynd beds beneath Barrande's so-called primordial zone. The presence of phosphatic nodules and bituminous matter in some of the lowest azoic rocks, probably indicates the former existence of life at these periods. But the difficulty of understanding the absence of vast piles of fossiliferous strata, which on my theory no doubt were somewhere accumulated before the Silurian epoch, is very great. If these most ancient beds had been wholly worn away by denudation, or obliterated by metamorphic action, we ought to find only small remnants of the formations next succeeding them in age, and these ought to be very generally in a metamorphosed condition. But the descriptions which we now possess of the Silurian deposits over immense territories in Russia and in North America, do not support the view, that the older a formation is, the more it has suffered the extremity of denudation and metamorphism.

The case at present must remain inexplicable; and may be truly urged as a valid argument against the views here entertained. To show that it may hereafter receive some explanation, I will give the following hypothesis. From the nature of the organic remains, which do not appear to have inhabited profound depths, in the several formations of Europe and of the United States; and from the amount of sediment, miles in thickness, of which the formations are composed, we may infer that from first to last large islands or tracts of land, whence the sediment was derived, occurred in the neighbourhood of the existing continents of Europe and North America. But we do not know what was the state of things in the intervals between the successive formations; whether Europe and the United States during these intervals existed as dry land, or as a submarine surface near land, on which sediment was not deposited, or again as the bed of an open and unfathomable sea.

Looking to the existing oceans, which are thrice as extensive as the land, we see them studded with many islands; but not one oceanic island is as yet known to afford even a remnant of any palaeozoic or secondary formation. Hence we may perhaps infer, that during the palaeozoic and secondary periods, neither continents nor continental islands existed where our oceans now extend; for had they existed there, palaeozoic and secondary formations would in all probability have been accumulated from sediment derived from their wear and tear; and would have been at least partially upheaved by the oscillations of level, which we may fairly conclude must have intervened during these enormously long periods. If then we may infer anything from these facts, we may infer that where our oceans now extend, oceans have extended from the remotest period of which we have any record; and on the other hand, that where continents now exist, large tracts of land have existed, subjected no doubt to great oscillations of level, since the earliest silurian period. The coloured map appended to my volume on Coral Reefs, led me to conclude that the great oceans are still mainly areas of subsidence, the great archipelagoes still areas of oscillations of level, and the continents areas of elevation. But have we any right to assume that things have thus remained from eternity? Our continents seem to have been formed by a preponderance, during many oscillations of level, of the force of elevation; but may not the areas of preponderant movement have changed in the lapse of ages? At a period immeasurably antecedent to the silurian epoch, continents may have existed where oceans are now spread out; and clear and open oceans may have existed where our continents now stand. Nor should we be justified in assuming that if, for instance, the bed of the Pacific Ocean were now converted into a continent, we should there find formations older than the silurian strata, supposing such to have been formerly deposited; for it might well happen that strata which had subsided some miles nearer to the centre of the earth, and which had been pressed on by an enormous weight of superincumbent water, might have undergone far more metamorphic action than strata which have always remained nearer to the surface. The immense areas in some parts of the world, for instance in South America, of bare metamorphic rocks, which must have been heated under great pressure, have always seemed to me to require some special explanation; and we may perhaps believe that we see in these large areas, the many formations long anterior to the silurian epoch in a completely metamorphosed condition.

The several difficulties here discussed, namely our not finding in the successive formations infinitely numerous transitional links between the many species which now exist or have existed; the sudden manner in which whole groups of species appear in our European formations; the almost entire absence, as at present known, of fossiliferous formations beneath the Silurian strata, are all undoubtedly of the gravest nature. We see this in the plainest manner by the fact that all the most eminent palaeontologists, namely Cuvier, Owen, Agassiz, Barrande, Falconer, E. Forbes, &c., and all our greatest geologists, as Lyell, Murchison, Sedgwick, &c., have unanimously, often vehemently, maintained the immutability of species. But I have reason to believe that one great authority, Sir Charles Lyell, from further reflexion entertains grave doubts on this subject. I feel how rash it is to differ from these great authorities, to whom, with others, we owe all our knowledge. Those who think the natural geological record in any degree perfect, and who do not attach much weight to the facts and arguments of other kinds even in this volume, will undoubtedly at once reject my theory. For my part, following out Lyell's metaphor, I look at the natural geological record, as a history of the world imperfectly kept, and written in a changing dialect; of this history we possess the last volume alone, relating only to two or three countries. Of this volume, only here and there a short chapter has been preserved; and of each page, only here and there a few lines. Each word of the slowly-changing language, in which the history is supposed to be written, being more or less different in the interrupted succession of chapters, may represent the apparently abruptly changed forms of life, entombed in our consecutive, but widely separated formations. On this view, the difficulties above discussed are greatly diminished, or even disappear. Let us now see whether the several facts and rules relating to the geological succession of organic beings, better accord with the common view of the immutability of species, or with that of their slow and gradual modification, through descent and natural selection.

New species have appeared very slowly, one after another, both on the land and in the waters. Lyell has shown that it is hardly possible to resist the evidence on this head in the case of the several tertiary stages; and every year tends to fill up the blanks between them, and to make the percentage system of lost and new forms more gradual. In some of the most recent beds, though undoubtedly of high antiquity if measured by years, only one or two species are lost forms, and only one or two are new forms, having here appeared for the first time, either locally, or, as far as we know, on the face of the earth. If we may trust the observations of Philippi in Sicily, the successive changes in the marine inhabitants of that island have been many and most gradual. The secondary formations are more broken; but, as Bronn has remarked, neither the appearance nor disappearance of their many now extinct species has been simultaneous in each separate formation.

Species of different genera and classes have not changed at the same rate, or in the same degree. In the oldest tertiary beds a few living shells may still be found in the midst of a multitude of extinct forms. Falconer has given a striking instance of a similar fact, in an existing crocodile associated with many strange and lost mammals and reptiles in the sub-Himalayan deposits. The Silurian Lingula differs but little from the living species of this genus; whereas most of the other Silurian Molluscs and all the Crustaceans have changed greatly. The productions of the land seem to change at a quicker rate than those of the sea, of which a striking instance has lately been observed in Switzerland. There is some reason to believe that organisms, considered high in the scale of nature, change more quickly than those that are low: though there are exceptions to this rule. The amount of organic change, as Pictet has remarked, does not strictly correspond with the succession of our geological formations; so that between each two consecutive formations, the forms of life have seldom changed in exactly the same degree. Yet if we compare any but the most closely related formations, all the species will be found to have undergone some change. When a species has once disappeared from the face of the earth, we have reason to believe that the same identical form never reappears. The strongest apparent exception to this latter rule, is that of the so-called `colonies' of M. Barrande, which intrude for a period in the midst of an older formation, and then allow the pre-existing fauna to reappear; but Lyell's explanation, namely, that it is a case of temporary migration from a distinct geographical province, seems to me satisfactory.

These several facts accord well with my theory. I believe in no fixed law of development, causing all the inhabitants of a country to change abruptly, or simultaneously, or to an equal degree. The process of modification must be extremely slow. The variability of each species is quite independent of that of all others. Whether such variability be taken advantage of by natural selection, and whether the variations be accumulated to a greater or lesser amount, thus causing a greater or lesser amount of modification in the varying species, depends on many complex contingencies, on the variability being of a beneficial nature, on the power of intercrossing, on the rate of breeding, on the slowly changing physical conditions of the country, and more especially on the nature of the other inhabitants with which the varying species comes into competition. Hence it is by no means surprising that one species should retain the same identical form much longer than others; or, if changing, that it should change less. We see the same fact in geographical distribution; for instance, in the land-shells and coleopterous insects of Madeira having come to differ considerably from their nearest allies on the continent of Europe, whereas the marine shells and birds have remained unaltered. We can perhaps understand the apparently quicker rate of change in terrestrial and in more highly organised productions compared with marine and lower productions, by the more complex relations of the higher beings to their organic and inorganic conditions of life, as explained in a former chapter. When many of the inhabitants of a country have become modified and improved, we can understand, on the principle of competition, and on that of the many all-important relations of organism to organism, that any form which does not become in some degree modified and improved, will be liable to be exterminated. Hence we can see why all the species in the same region do at last, if we look to wide enough intervals of time, become modified; for those which do not change will become extinct.

In members of the same class the average amount of change, during long and equal periods of time, may, perhaps, be nearly the same; but as the accumulation of long-enduring fossiliferous formations depends on great masses of sediment having been deposited on areas whilst subsiding, our formations have been almost necessarily accumulated at wide and irregularly intermittent intervals; consequently the amount of organic change exhibited by the fossils embedded in consecutive formations is not equal. Each formation, on this view, does not mark a new and complete act of creation, but only an occasional scene, taken almost at hazard, in a slowly changing drama.

We can clearly understand why a species when once lost should never reappear, even if the very same conditions of life, organic and inorganic, should recur. For though the offspring of one species might be adapted (and no doubt this has occurred in innumerable instances) to fill the exact place of another species in the economy of nature, and thus supplant it; yet the two forms the old and the new would not be identically the same; for both would almost certainly inherit different characters from their distinct progenitors. For instance, it is just possible, if our fantail-pigeons were all destroyed, that fanciers, by striving during long ages for the same object, might make a new breed hardly distinguishable from our present fantail; but if the parent rock-pigeon were also destroyed, and in nature we have every reason to believe that the parent-form will generally be supplanted and exterminated by its improved offspring, it is quite incredible that a fantail, identical with the existing breed, could be raised from any other species of pigeon, or even from the other well-established races of the domestic pigeon, for the newly-formed fantail would be almost sure to inherit from its new progenitor some slight characteristic differences.

Groups of species, that is, genera and families, follow the same general rules in their appearance and disappearance as do single species, changing more or less quickly, and in a greater or lesser degree. A group does not reappear after it has once disappeared; or its existence, as long as it lasts, is continuous. I am aware that there are some apparent exceptions to this rule, but the exceptions are surprisingly few, so few, that E. Forbes, Pictet, and Woodward (though all strongly opposed to such views as I maintain) admit its truth; and the rule strictly accords with my theory. For as all the species of the same group have descended from some one species, it is clear that as long as any species of the group have appeared in the long succession of ages, so long must its members have continuously existed, in order to have generated either new and modified or the same old and unmodified forms. Species of the genus Lingula, for instance, must have continuously existed by an unbroken succession of generations, from the lowest Silurian stratum to the present day.

We have seen in the last chapter that the species of a group sometimes falsely appear to have come in abruptly; and I have attempted to give an explanation of this fact, which if true would have been fatal to my views. But such cases are certainly exceptional; the general rule being a gradual increase in number, till the group reaches its maximum, and then, sooner or later, it gradually decreases. If the number of the species of a genus, or the number of the genera of a family, be represented by a vertical line of varying thickness, crossing the successive geological formations in which the species are found, the line will sometimes falsely appear to begin at its lower end, not in a sharp point, but abruptly; it then gradually thickens upwards, sometimes keeping for a space of equal thickness, and ultimately thins out in the upper beds, marking the decrease and final extinction of the species. This gradual increase in number of the species of a group is strictly conformable with my theory; as the species of the same genus, and the genera of the same family, can increase only slowly and progressively; for the process of modification and the production of a number of allied forms must be slow and gradual, one species giving rise first to two or three varieties, these being slowly converted into species, which in their turn produce by equally slow steps other species, and so on, like the branching of a great tree from a single stem, till the group becomes large.

On Extinction

We have as yet spoken only incidentally of the disappearance of species and of groups of species. On the theory of natural selection the extinction of old forms and the production of new and improved forms are intimately connected together. The old notion of all the inhabitants of the earth having been swept away at successive periods by catastrophes, is very generally given up, even by those geologists, as Elie de Beaumont, Murchison, Barrande, &c., whose general views would naturally lead them to this conclusion. On the contrary, we have every reason to believe, from the study of the tertiary formations, that species and groups of species gradually disappear, one after another, first from one spot, then from another, and finally from the world. Both single species and whole groups of species last for very unequal periods; some groups, as we have seen, having endured from the earliest known dawn of life to the present day; some having disappeared before the close of the palaeozoic period. No fixed law seems to determine the length of time during which any single species or any single genus endures. There is reason to believe that the complete extinction of the species of a group is generally a slower process than their production: if the appearance and disappearance of a group of species be represented, as before, by a vertical line of varying thickness, the line is found to taper more gradually at its upper end, which marks the progress of extermination, than at its lower end, which marks the first appearance and increase in numbers of the species. In some cases, however, the extermination of whole groups of beings, as of ammonites towards the close of the secondary period, has been wonderfully sudden.

The whole subject of the extinction of species has been involved in the most gratuitous mystery. Some authors have even supposed that as the individual has a definite length of life, so have species a definite duration. No one I think can have marvelled more at the extinction of species, than I have done. When I found in La Plata the tooth of a horse embedded with the remains of Mastodon, Megatherium, Toxodon, and other extinct monsters, which all co-existed with still living shells at a very late geological period, I was filled with astonishment; for seeing that the horse, since its introduction by the Spaniards into South America, has run wild over the whole country and has increased in numbers at an unparalleled rate, I asked myself what could so recently have exterminated the former horse under conditions of life apparently so favourable. But how utterly groundless was my astonishment! Professor Owen soon perceived that the tooth, though so like that of the existing horse, belonged to an extinct species. Had this horse been still living, but in some degree rare, no naturalist would have felt the least surprise at its rarity; for rarity is the attribute of a vast number of species of all classes, in all countries. If we ask ourselves why this or that species is rare, we answer that something is unfavourable in its conditions of life; but what that something is, we can hardly ever tell. On the supposition of the fossil horse still existing as a rare species, we might have felt certain from the analogy of all other mammals, even of the slow-breeding elephant, and from the history of the naturalisation of the domestic horse in South America, that under more favourable conditions it would in a very few years have stocked the whole continent. But we could not have told what the unfavourable conditions were which checked its increase, whether some one or several contingencies, and at what period of the horse's life, and in what degree, they severally acted. If the conditions had gone on, however slowly, becoming less and less favourable, we assuredly should not have perceived the fact, yet the fossil horse would certainly have become rarer and rarer, and finally extinct; its place being seized on by some more successful competitor.

It is most difficult always to remember that the increase of every living being is constantly being checked by unperceived injurious agencies; and that these same unperceived agencies are amply sufficient to cause rarity, and finally extinction. We see in many cases in the more recent tertiary formations, that rarity precedes extinction; and we know that this has been the progress of events with those animals which have been exterminated, either locally or wholly, through man's agency. I may repeat what I published in 1845, namely, that to admit that species generally become rare before they become extinct to feel no surprise at the rarity of a species, and yet to marvel greatly when it ceases to exist, is much the same as to admit that sickness in the individual is the forerunner of death to feel no surprise at sickness, but when the sick man dies, to wonder and to suspect that he died by some unknown deed of violence.

The theory of natural selection is grounded on the belief that each new variety, and ultimately each new species, is produced and maintained by having some advantage over those with which it comes into competition; and the consequent extinction of less-favoured forms almost inevitably follows. It is the same with our domestic productions: when a new and slightly improved variety has been raised, it at first supplants the less improved varieties in the same neighbourhood; when much improved it is transported far and near, like our short-horn cattle, and takes the place of other breeds in other countries. Thus the appearance of new forms and the disappearance of old forms, both natural and artificial, are bound together. In certain flourishing groups, the number of new specific forms which have been produced within a given time is probably greater than that of the old forms which have been exterminated; but we know that the number of species has not gone on indefinitely increasing, at least during the later geological periods, so that looking to later times we may believe that the production of new forms has caused the extinction of about the same number of old forms.

The competition will generally be most severe, as formerly explained and illustrated by examples, between the forms which are most like each other in all respects. Hence the improved and modified descendants of a species will generally cause the extermination of the parent-species; and if many new forms have been developed from any one species, the nearest allies of that species, i.e. the species of the same genus, will be the most liable to extermination. Thus, as I believe, a number of new species descended from one species, that is a new genus, comes to supplant an old genus, belonging to the same family. But it must often have happened that a new species belonging to some one group will have seized on the place occupied by a species belonging to a distinct group, and thus caused its extermination; and if many allied forms be developed from the successful intruder, many will have to yield their places; and it will generally be allied forms, which will suffer from some inherited inferiority in common. But whether it be species belonging to the same or to a distinct class, which yield their places to other species which have been modified and improved, a few of the sufferers may often long be preserved, from being fitted to some peculiar line of life, or from inhabiting some distant and isolated station, where they have escaped severe competition. For instance, a single species of Trigonia, a great genus of shells in the secondary formations, survives in the Australian seas; and a few members of the great and almost extinct group of Ganoid fishes still inhabit our fresh waters. Therefore the utter extinction of a group is generally, as we have seen, a slower process than its production.

With respect to the apparently sudden extermination of whole families or orders, as of Trilobites at the close of the palaeozoic period and of Ammonites at the close of the secondary period, we must remember what has been already said on the probable wide intervals of time between our consecutive formations; and in these intervals there may have been much slow extermination. Moreover, when by sudden immigration or by unusually rapid development, many species of a new group have taken possession of a new area, they will have exterminated in a correspondingly rapid manner many of the old inhabitants; and the forms which thus yield their places will commonly be allied, for they will partake of some inferiority in common.

Thus, as it seems to me, the manner in which single species and whole groups of species become extinct, accords well with the theory of natural selection. We need not marvel at extinction; if we must marvel, let it be at our presumption in imagining for a moment that we understand the many complex contingencies, on which the existence of each species depends. If we forget for an instant, that each species tends to increase inordinately, and that some check is always in action, yet seldom perceived by us, the whole economy of nature will be utterly obscured. Whenever we can precisely say why this species is more abundant in individuals than that; why this species and not another can be naturalised in a given country; then, and not till then, we may justly feel surprise why we cannot account for the extinction of this particular species or group of species.

On the Forms of Life changing almost simultaneously throughout the World

Scarcely any palaeontological discovery is more striking than the fact, that the forms of life change almost simultaneously throughout the world. Thus our European Chalk formation can be recognised in many distant parts of the world, under the most different climates, where not a fragment of the mineral chalk itself can be found; namely, in North America, in equatorial South America, in Tierra del Fuego, at the Cape of Good Hope, and in the peninsula of India. For at these distant points, the organic remains in certain beds present an unmistakeable degree of resemblance to those of the Chalk. It is not that the same species are met with; for in some cases not one species is identically the same, but they belong to the same families, genera, and sections of genera, and sometimes are similarly characterised in such trifling points as mere superficial sculpture. Moreover other forms, which are not found in the Chalk of Europe, but which occur in the formations either above or below, are similarly absent at these distant points of the world. In the several successive palaeozoic formations of Russia, Western Europe and North America, a similar parallelism in the forms of life has been observed by several authors: so it is, according to Lyell, with the several European and North American tertiary deposits. Even if the few fossil species which are common to the Old and New Worlds be kept wholly out of view, the general parallelism in the successive forms of life, in the stages of the widely separated palaeozoic and tertiary periods, would still be manifest, and the several formations could be easily correlated.

These observations, however, relate to the marine inhabitants of distant parts of the world: we have not sufficient data to judge whether the productions of the land and of fresh water change at distant points in the same parallel manner. We may doubt whether they have thus changed: if the Megatherium, Mylodon, Macrauchenia, and Toxodon had been brought to Europe from La Plata, without any information in regard to their geological position, no one would have suspected that they had coexisted with still living sea-shells; but as these anomalous monsters coexisted with the Mastodon and Horse, it might at least have been inferred that they had lived during one of the latter tertiary stages.

When the marine forms of life are spoken of as having changed simultaneously throughout the world, it must not be supposed that this expression relates to the same thousandth or hundred-thousandth year, or even that it has a very strict geological sense; for if all the marine animals which live at the present day in Europe, and all those that lived in Europe during the pleistocene period (an enormously remote period as measured by years, including the whole glacial epoch), were to be compared with those now living in South America or in Australia, the most skilful naturalist would hardly be able to say whether the existing or the pleistocene inhabitants of Europe resembled most closely those of the southern hemisphere. So, again, several highly competent observers believe that the existing productions of the United States are more closely related to those which lived in Europe during certain later tertiary stages, than to those which now live here; and if this be so, it is evident that fossiliferous beds deposited at the present day on the shores of North America would hereafter be liable to be classed with somewhat older European beds. Nevertheless, looking to a remotely future epoch, there can, I think, be little doubt that all the more modern marine formations, namely, the upper pliocene, the pleistocene and strictly modern beds, of Europe, North and South America, and Australia, from containing fossil remains in some degree allied, and from not including those forms which are only found in the older underlying deposits, would be correctly ranked as simultaneous in a geological sense.

The fact of the forms of life changing simultaneously, in the above large sense, at distant parts of the world, has greatly struck those admirable observers, MM. de Verneuil and d'Archiac. After referring to the parallelism of the palaeozoic forms of life in various parts of Europe, they add, `If struck by this strange sequence, we turn our attention to North America, and there discover a series of analogous phenomena, it will appear certain that all these modifications of species, their extinction, and the introduction of new ones, cannot be owing to mere changes in marine currents or other causes more or less local and temporary, but depend on general laws which govern the whole animal kingdom.' M. Barrande has made forcible remarks to precisely the same effect. It is, indeed, quite futile to look to changes of currents, climate, or other physical conditions, as the cause of these great mutations in the forms of life throughout the world, under the most different climates. We must, as Barrande has remarked, look to some special law. We shall see this more clearly when we treat of the present distribution of organic beings, and find how slight is the relation between the physical conditions of various countries, and the nature of their inhabitants.

This great fact of the parallel succession of the forms of life throughout the world, is explicable on the theory of natural selection. New species are formed by new varieties arising, which have some advantage over older forms; and those forms, which are already dominant, or have some advantage over the other forms in their own country, would naturally oftenest give rise to new varieties or incipient species; for these latter must be victorious in a still higher degree in order to be preserved and to survive. We have distinct evidence on this head, in the plants which are dominant, that is, which are commonest in their own homes, and are most widely diffused, having produced the greatest number of new varieties. It is also natural that the dominant, varying, and far-spreading species, which already have invaded to a certain extent the territories of other species, should be those which would have the best chance of spreading still further, and of giving rise in new countries to new varieties and species. The process of diffusion may often be very slow, being dependent on climatal and geographical changes, or on strange accidents, but in the long run the dominant forms will generally succeed in spreading. The diffusion would, it is probable, be slower with the terrestrial inhabitants of distinct continents than with the marine inhabitants of the continuous sea. We might therefore expect to find, as we apparently do find, a less strict degree of parallel succession in the productions of the land than of the sea.

Dominant species spreading from any region might encounter still more dominant species, and then their triumphant course, or even their existence, would cease. We know not at all precisely what are all the conditions most favourable for the multiplication of new and dominant species; but we can, I think, clearly see that a number of individuals, from giving a better chance of the appearance of favourable variations, and that severe competition with many already existing forms, would be highly favourable, as would be the power of spreading into new territories. A certain amount of isolation, recurring at long intervals of time, would probably be also favourable, as before explained. One quarter of the world may have been most favourable for the production of new and dominant species on the land, and another for those in the waters of the sea. If two great regions had been for a long period favourably circumstanced in an equal degree, whenever their inhabitants met, the battle would be prolonged and severe; and some from one birthplace and some from the other might be victorious. But in the course of time, the forms dominant in the highest degree, wherever produced, would tend everywhere to prevail. As they prevailed, they would cause the extinction of other and inferior forms; and as these inferior forms would be allied in groups by inheritance, whole groups would tend slowly to disappear; though here and there a single member might long be enabled to survive.

Thus, as it seems to me, the parallel, and, taken in a large sense, simultaneous, succession of the same forms of life throughout the world, accords well with the principle of new species having been formed by dominant species spreading widely and varying; the new species thus produced being themselves dominant owing to inheritance, and to having already had some advantage over their parents or over other species; these again spreading, varying, and producing new species. The forms which are beaten and which yield their places to the new and victorious forms, will generally be allied in groups, from inheriting some inferiority in common; and therefore as new and improved groups spread throughout the world, old groups will disappear from the world; and the succession of forms in both ways will everywhere tend to correspond.

There is one other remark connected with this subject worth making. I have given my reasons for believing that all our greater fossiliferous formations were deposited during periods of subsidence; and that blank intervals of vast duration occurred during the periods when the bed of the sea was either stationary or rising, and likewise when sediment was not thrown down quickly enough to embed and preserve organic remains. During these long and blank intervals I suppose that the inhabitants of each region underwent a considerable amount of modification and extinction, and that there was much migration from other parts of the world. As we have reason to believe that large areas are affected by the same movement, it is probable that strictly contemporaneous formations have often been accumulated over very wide spaces in the same quarter of the world; but we are far from having any right to conclude that this has invariably been the case, and that large areas have invariably been affected by the same movements. When two formations have been deposited in two regions during nearly, but not exactly the same period, we should find in both, from the causes explained in the foregoing paragraphs, the same general succession in the forms of life; but the species would not exactly correspond; for there will have been a little more time in the one region than in the other for modification, extinction, and immigration.

I suspect that cases of this nature have occurred in Europe. Mr. Prestwich, in his admirable Memoirs on the eocene deposits of England and France, is able to draw a close general parallelism between the successive stages in the two countries; but when he compares certain stages in England with those in France, although he finds in both a curious accordance in the numbers of the species belonging to the same genera, yet the species themselves differ in a manner very difficult to account for, considering the proximity of the two areas, unless, indeed, it be assumed that an isthmus separated two seas inhabited by distinct, but contemporaneous, faunas. Lyell has made similar observations on some of the later tertiary formations. Barrande, also, shows that there is a striking general parallelism in the successive Silurian deposits of Bohemia and Scandinavia; nevertheless he finds a surprising amount of difference in the species. If the several formations in these regions have not been deposited during the same exact periods, a formation in one region often corresponding with a blank interval in the other, and if in both regions the species have gone on slowly changing during the accumulation of the several formations and during the long intervals of time between them; in this case, the several formations in the two regions could be arranged in the same order, in accordance with the general succession of the form of life, and the order would falsely appear to be strictly parallel; nevertheless the species would not all be the same in the apparently corresponding stages in the two regions.

On the Affinities of extinct Species to each other, and to living forms

Let us now look to the mutual affinities of extinct and living species. They all fall into one grand natural system; and this fact is at once explained on the principle of descent. The more ancient any form is, the more, as a general rule, it differs from living forms. But, as Buckland long ago remarked, all fossils can be classed either in still existing groups, or between them. That the extinct forms of life help to fill up the wide intervals between existing genera, families, and orders, cannot be disputed. For if we confine our attention either to the living or to the extinct alone, the series is far less perfect than if we combine both into one general system. With respect to the Vertebrata, whole pages could be filled with striking illustrations from our great palaeontologist, Owen, showing how extinct animals fall in between existing groups. Cuvier ranked the Ruminants and Pachyderms, as the two most distinct orders of mammals; but Owen has discovered so many fossil links, that he has had to alter the whole classification of these two orders; and has placed certain pachyderms in the same sub-order with ruminants: for example, he dissolves by fine gradations the apparently wide difference between the pig and the camel. In regard to the Invertebrata, Barrande, and a higher authority could not be named, asserts that he is every day taught that palaeozoic animals, though belonging to the same orders, families, or genera with those living at the present day, were not at this early epoch limited in such distinct groups as they now are.

Some writers have objected to any extinct species or group of species being considered as intermediate between living species or groups. If by this term it is meant that an extinct form is directly intermediate in all its characters between two living forms, the objection is probably valid. But I apprehend that in a perfectly natural classification many fossil species would have to stand between living species, and some extinct genera between living genera, even between genera belonging to distinct families. The most common case, especially with respect to very distinct groups, such as fish and reptiles, seems to be, that supposing them to be distinguished at the present day from each other by a dozen characters, the ancient members of the same two groups would be distinguished by a somewhat lesser number of characters, so that the two groups, though formerly quite distinct, at that period made some small approach to each other.

It is a common belief that the more ancient a form is, by so much the more it tends to connect by some of its characters groups now widely separated from each other. This remark no doubt must be restricted to those groups which have undergone much change in the course of geological ages; and it would be difficult to prove the truth of the proposition, for every now and then even a living animal, as the Lepidosiren, is discovered having affinities directed towards very distinct groups. Yet if we compare the older Reptiles and Batrachians, the older Fish, the older Cephalopods, and the eocene Mammals, with the more recent members of the same classes, we must admit that there is some truth in the remark.

Let us see how far these several facts and inferences accord with the theory of descent with modification. As the subject is somewhat complex, I must request the reader to turn to the diagram in the fourth chapter. We may suppose that the numbered letters represent genera, and the dotted lines diverging from them the species in each genus. The diagram is much too simple, too few genera and too few species being given, but this is unimportant for us. The horizontal lines may represent successive geological formations, and all the forms beneath the uppermost line may be considered as extinct. The three existing genera, a14, q14, p14, will form a small family; b14 and f14 a closely allied family or sub-family; and o14, e14, m14, a third family. These three families, together with the many extinct genera on the several lines of descent diverging from the parent-form A, will form an order; for all will have inherited something in common from their ancient and common progenitor. On the principle of the continued tendency to divergence of character, which was formerly illustrated by this diagram, the more recent any form is, the more it will generally differ from its ancient progenitor. Hence we can understand the rule that the most ancient fossils differ most from existing forms. We must not, however, assume that divergence of character is a necessary contingency; it depends solely on the descendants from a species being thus enabled to seize on many and different places in the economy of nature. Therefore it is quite possible, as we have seen in the case of some Silurian forms, that a species might go on being slightly modified in relation to its slightly altered conditions of life, and yet retain throughout a vast period the same general characteristics. This is represented in the diagram by the letter F14.

All the many forms, extinct and recent, descended from A, make, as before remarked, one order; and this order, from the continued effects of extinction and divergence of character, has become divided into several sub-families and families, some of which are supposed to have perished at different periods, and some to have endured to the present day.

By looking at the diagram we can see that if many of the extinct forms, supposed to be embedded in the successive formations, were discovered at several points low down in the series, the three existing families on the uppermost line would be rendered less distinct from each other. If, for instance, the genera a1, a5, a10, m3, m6, m9 were disinterred, these three families would be so closely linked together that they probably would have to be united into one great family, in nearly the same manner as has occurred with ruminants and pachyderms. Yet he who objected to call the extinct genera, which thus linked the living genera of three families together, intermediate in character, would be justified, as they are intermediate, not directly, but only by a long and circuitous course through many widely different forms. If many extinct forms were to be discovered above one of the middle horizontal lines or geological formations for instance, above No. VI. but none from beneath this line, then only the two families on the left hand (namely, a14, &c., and b14, &c.) would have to be united into one family; and the two other families (namely, a14 to f14 now including five genera, and o14 to m14) would yet remain distinct. These two families, however, would be less distinct from each other than they were before the discovery of the fossils. If, for instance, we suppose the existing genera of the two families to differ from each other by a dozen characters, in this case the genera, at the early period marked VI., would differ by a lesser number of characters; for at this early stage of descent they have not diverged in character from the common progenitor of the order, nearly so much as they subsequently diverged. Thus it comes that ancient and extinct genera are often in some slight degree intermediate in character between their modified descendants, or between their collateral relations.

In nature the case will be far more complicated than is represented in the diagram; for the groups will have been more numerous, they will have endured for extremely unequal lengths of time, and will have been modified in various degrees. As we possess only the last volume of the geological record, and that in a very broken condition, we have no right to expect, except in very rare cases, to fill up wide intervals in the natural system, and thus unite distinct families or orders. All that we have a right to expect, is that those groups, which have within known geological periods undergone much modification, should in the older formations make some slight approach to each other; so that the older members should differ less from each other in some of their characters than do the existing members of the same groups; and this by the concurrent evidence of our best palaeontologists seems frequently to be the case.

Thus, on the theory of descent with modification, the main facts with respect to the mutual affinities of the extinct forms of life to each other and to living forms, seem to me explained in a satisfactory manner. And they are wholly inexplicable on any other view.

On this same theory, it is evident that the fauna of any great period in the earth's history will be intermediate in general character between that which preceded and that which succeeded it. Thus, the species which lived at the sixth great stage of descent in the diagram are the modified offspring of those which lived at the fifth stage, and are the parents of those which became still more modified at the seventh stage; hence they could hardly fail to be nearly intermediate in character between the forms of life above and below. We must, however, allow for the entire extinction of some preceding forms, and for the coming in of quite new forms by immigration, and for a large amount of modification, during the long and blank intervals between the successive formations. Subject to these allowances, the fauna of each geological period undoubtedly is intermediate in character, between the preceding and succeeding faunas. I need give only one instance, namely, the manner in which the fossils of the Devonian system, when this system was first discovered, were at once recognised by palaeontologists as intermediate in character between those of the overlying carboniferous, and underlying Silurian system. But each fauna is not necessarily exactly intermediate, as unequal intervals of time have elapsed between consecutive formations.

It is no real objection to the truth of the statement, that the fauna of each period as a whole is nearly intermediate in character between the preceding and succeeding faunas, that certain genera offer exceptions to the rule. For instance, mastodons and elephants, when arranged by Dr Falconer in two series, first according to their mutual affinities and then according to their periods of existence, do not accord in arrangement. The species extreme in character are not the oldest, or the most recent; nor are those which are intermediate in character, intermediate in age. But supposing for an instant, in this and other such cases, that the record of the first appearance and disappearance of the species was perfect, we have no reason to believe that forms successively produced necessarily endure for corresponding lengths of time: a very ancient form might occasionally last much longer than a form elsewhere subsequently produced, especially in the case of terrestrial productions inhabiting separated districts. To compare small things with great: if the principal living and extinct races of the domestic pigeon were arranged as well as they could be in serial affinity, this arrangement would not closely accord with the order in time of their production, and still less with the order of their disappearance; for the parent rock-pigeon now lives; and many varieties between the rock-pigeon and the carrier have become extinct; and carriers which are extreme in the important character of length of beak originated earlier than short-beaked tumblers, which are at the opposite end of the series in this same respect.

Closely connected with the statement, that the organic remains from an intermediate formation are in some degree intermediate in character, is the fact, insisted on by all palaeontologists, that fossils from two consecutive formations are far more closely related to each other, than are the fossils from two remote formations. Pictet gives as a well-known instance, the general resemblance of the organic remains from the several stages of the chalk formation, though the species are distinct in each stage. This fact alone, from its generality, seems to have shaken Professor Pictet in his firm belief in the immutability of species. He who is acquainted with the distribution of existing species over the globe, will not attempt to account for the close resemblance of the distinct species in closely consecutive formations, by the physical conditions of the ancient areas having remained nearly the same. Let it be remembered that the forms of life, at least those inhabiting the sea, have changed almost simultaneously throughout the world, and therefore under the most different climates and conditions. Consider the prodigious vicissitudes of climate during the pleistocene period, which includes the whole glacial period, and note how little the specific forms of the inhabitants of the sea have been affected.

On the theory of descent, the full meaning of the fact of fossil remains from closely consecutive formations, though ranked as distinct species, being closely related, is obvious. As the accumulation of each formation has often been interrupted, and as long blank intervals have intervened between successive formations, we ought not to expect to find, as I attempted to show in the last chapter, in any one or two formations all the intermediate varieties between the species which appeared at the commencement and close of these periods; but we ought to find after intervals, very long as measured by years, but only moderately long as measured geologically, closely allied forms, or, as they have been called by some authors, representative species; and these we assuredly do find. We find, in short, such evidence of the slow and scarcely sensible mutation of specific forms, as we have a just right to expect to find.

On the state of Development of Ancient Forms

There has been much discussion whether recent forms are more highly developed than ancient. I will not here enter on this subject, for naturalists have not as yet defined to each other's satisfaction what is meant by high and low forms. But in one particular sense the more recent forms must, on my theory, be higher than the more ancient; for each new species is formed by having had some advantage in the struggle for life over other and preceding forms. If under a nearly similar climate, the eocene inhabitants of one quarter of the world were put into competition with the existing inhabitants of the same or some other quarter, the eocene fauna or flora would certainly be beaten and exterminated; as would a secondary fauna by an eocene, and a palaeozoic fauna by a secondary fauna. I do not doubt that this process of improvement has affected in a marked and sensible manner the organisation of the more recent and victorious forms of life, in comparison with the ancient and beaten forms; but I can see no way of testing this sort of progress. Crustaceans, for instance, not the highest in their own class, may have beaten the highest molluscs. From the extraordinary manner in which European productions have recently spread over New Zealand, and have seized on places which must have been previously occupied, we may believe, if all the animals and plants of Great Britain were set free in New Zealand, that in the course of time a multitude of British forms would become thoroughly naturalized there, and would exterminate many of the natives. On the other hand, from what we see now occurring in New Zealand, and from hardly a single inhabitant of the southern hemisphere having become wild in any part of Europe, we may doubt, if all the productions of New Zealand were set free in Great Britain, whether any considerable number would be enabled to seize on places now occupied by our native plants and animals. Under this point of view, the productions of Great Britain, may be said to be higher than those of New Zealand. Yet the most skilful naturalist from an examination of the species of the two countries could not have foreseen this result.

Agassiz insists that ancient animals resemble to a certain extent the embryos of recent animals of the same classes; or that the geological succession of extinct forms is in some degree parallel to the embryological development of recent forms. I must follow Pictet and Huxley in thinking that the truth of this doctrine is very far from proved. Yet I fully expect to see it hereafter confirmed, at least in regard to subordinate groups, which have branched off from each other within comparatively recent times. For this doctrine of Agassiz accords well with the theory of natural selection. In a future chapter I shall attempt to show that the adult differs from its embryo, owing to variations supervening at a not early age, and being inherited at a corresponding age. This process, whilst it leaves the embryo almost unaltered, continually adds, in the course of successive generations, more and more difference to the adult.

Thus the embryo comes to be left as a sort of picture, preserved by nature, of the ancient and less modified condition of each animal. This view may be true, and yet it may never be capable of full proof. Seeing, for instance, that the oldest known mammals, reptiles, and fish strictly belong to their own proper classes, though some of these old forms are in a slight degree less distinct from each other than are the typical members of the same groups at the present day, it would be vain to look for animals having the common embryological character of the Vertebrata, until beds far beneath the lowest Silurian strata are discovered a discovery of which the chance is very small.
On the Succession of the same Types within the same areas, during the later tertiary periods

Mr Clift many years ago showed that the fossil mammals from the Australian caves were closely allied to the living marsupials of that continent. In South America, a similar relationship is manifest, even to an uneducated eye, in the gigantic pieces of armour like those of the armadillo, found in several parts of La Plata; and Professor Owen has shown in the most striking manner that most of the fossil mammals, buried there in such numbers, are related to South American types. This relationship is even more clearly seen in the wonderful collection of fossil bones made by MM. Lund and Clausen in the caves of Brazil. I was so much impressed with these facts that I strongly insisted, in 1839 and 1845, on this `law of the succession of types,' on `this wonderful relationship in the same continent between the dead and the living.' Professor Owen has subsequently extended the same generalisation to the mammals of the Old World. We see the same law in this author's restorations of the extinct and gigantic birds of New Zealand. We see it also in the birds of the caves of Brazil. Mr Woodward has shown that the same law holds good with sea-shells, but from the wide distribution of most genera of molluscs, it is not well displayed by them. Other cases could be added, as the relation between the extinct and living land-shells of Madeira; and between the extinct and living brackish-water shells of the Aralo-Caspian Sea.

Now what does this remarkable law of the succession of the same types within the same areas mean? He would be a bold man, who after comparing the present climate of Australia and of parts of South America under the same latitude, would attempt to account, on the one hand, by dissimilar physical conditions for the dissimilarity of the inhabitants of these two continents, and, on the other hand, by similarity of conditions, for the uniformity of the same types in each during the later tertiary periods. Nor can it be pretended that it is an immutable law that marsupials should have been chiefly or solely produced in Australia; or that Edentata and other American types should have been solely produced in South America. For we know that Europe in ancient times was peopled by numerous marsupials; and I have shown in the publications above alluded to, that in America the law of distribution of terrestrial mammals was formerly different from what it now is. North America formerly partook strongly of the present character of the southern half of the continent; and the southern half was formerly more closely allied, than it is at present, to the northern half. In a similar manner we know from Falconer and Cautley's discoveries, that northern India was formerly more closely related in its mammals to Africa than it is at the present time. Analogous facts could be given in relation to the distribution of marine animals.

On the theory of descent with modification, the great law of the long enduring, but not immutable, succession of the same types within the same areas, is at once explained; for the inhabitants of each quarter of the world will obviously tend to leave in that quarter, during the next succeeding period of time, closely allied though in some degree modified descendants. If the inhabitants of one continent formerly differed greatly from those of another continent, so will their modified descendants still differ in nearly the same manner and degree. But after very long intervals of time and after great geographical changes, permitting much inter-migration, the feebler will yield to the more dominant forms, and there will be nothing immutable in the laws of past and present distribution.

It may be asked in ridicule, whether I suppose that the megatherium and other allied huge monsters have left behind them in South America the sloth, armadillo, and anteater, as their degenerate descendants. This cannot for an instant be admitted. These huge animals have become wholly extinct, and have left no progeny. But in the caves of Brazil, there are many extinct species which are closely allied in size and in other characters to the species still living in South America; and some of these fossils may be the actual progenitors of living species. It must not be forgotten that, on my theory, all the species of the same genus have descended from some one species; so that if six genera, each having eight species, be found in one geological formation, and in the next succeeding formation there be six other allied or representative genera with the same number of species, then we may conclude that only one species of each of the six older genera has left modified descendants, constituting the six new genera. The other seven species of the old genera have all died out and have left no progeny. Or, which would probably be a far commoner case, two or three species of two or three alone of the six older genera will have been the parents of the six new genera; the other old species and the other whole genera having become utterly extinct. In failing orders, with the genera and species decreasing in numbers, as apparently is the case of the Edentata of South America, still fewer genera and species will have left modified blood-descendants.
Summary of the preceding and present Chapters

I have attempted to show that the geological record is extremely imperfect; that only a small portion of the globe has been geologically explored with care; that only certain classes of organic beings have been largely preserved in a fossil state; that the number both of specimens and of species, preserved in our museums, is absolutely as nothing compared with the incalculable number of generations which must have passed away even during a single formation; that, owing to subsidence being necessary for the accumulation of fossiliferous deposits thick enough to resist future degradation, enormous intervals of time have elapsed between the successive formations; that there has probably been more extinction during the periods of subsidence, and more variation during the periods of elevation, and during the latter the record will have been least perfectly kept; that each single formation has not been continuously deposited; that the duration of each formation is, perhaps, short compared with the average duration of specific forms; that migration has played an important part in the first appearance of new forms in any one area and formation; that widely ranging species are those which have varied most, and have oftenest given rise to new species; and that varieties have at first often been local. All these causes taken conjointly, must have tended to make the geological record extremely imperfect, and will to a large extent explain why we do not find interminable varieties, connecting together all the extinct and existing forms of life by the finest graduated steps.

He who rejects these views on the nature of the geological record, will rightly reject my whole theory. For he may ask in vain where are the numberless transitional links which must formerly have connected the closely allied or representative species, found in the several stages of the same great formation. He may disbelieve in the enormous intervals of time which have elapsed between our consecutive formations; he may overlook how important a part migration must have played, when the formations of any one great region alone, as that of Europe, are considered; he may urge the apparent, but often falsely apparent, sudden coming in of whole groups of species. He may ask where are the remains of those infinitely numerous organisms which must have existed long before the first bed of the Silurian system was deposited: I can answer this latter question only hypothetically, by saying that as far as we can see, where our oceans now extend they have for an enormous period extended, and where our oscillating continents now stand they have stood ever since the Silurian epoch; but that long before that period, the world may have presented a wholly different aspect; and that the older continents, formed of formations older than any known to us, may now all be in a metamorphosed condition, or may lie buried under the ocean.

Passing from these difficulties, all the other great leading facts in palaeontology seem to me simply to follow on the theory of descent with modification through natural selection. We can thus understand how it is that new species come in slowly and successively; how species of different classes do not necessarily change together, or at the same rate, or in the same degree; yet in the long run that all undergo modification to some extent. The extinction of old forms is the almost inevitable consequence of the production of new forms. We can understand why when a species has once disappeared it never reappears. Groups of species increase in numbers slowly, and endure for unequal periods of time; for the process of modification is necessarily slow, and depends on many complex contingencies. The dominant species of the larger dominant groups tend to leave many modified descendants, and thus new sub-groups and groups are formed. As these are formed, the species of the less vigorous groups, from their inferiority inherited from a common progenitor, tend to become extinct together, and to leave no modified offspring on the face of the earth. But the utter extinction of a whole group of species may often be a very slow process, from the survival of a few descendants, lingering in protected and isolated situations. When a group has once wholly disappeared, it does not reappear; for the link of generation has been broken.

We can understand how the spreading of the dominant forms of life, which are those that oftenest vary, will in the long run tend to people the world with allied, but modified, descendants; and these will generally succeed in taking the places of those groups of species which are their inferiors in the struggle for existence. Hence, after long intervals of time, the productions of the world will appear to have changed simultaneously.

We can understand how it is that all the forms of life, ancient and recent, make together one grand system; for all are connected by generation. We can understand, from the continued tendency to divergence of character, why the more ancient a form is, the more it generally differs from those now living. Why ancient and extinct forms often tend to fill up gaps between existing forms, sometimes blending two groups previously classed as distinct into one; but more commonly only bringing them a little closer together. The more ancient a form is, the more often, apparently, it displays characters in some degree intermediate between groups now distinct; for the more ancient a form is, the more nearly it will be related to, and consequently resemble, the common progenitor of groups, since become widely divergent. Extinct forms are seldom directly intermediate between existing forms; but are intermediate only by a long and circuitous course through many extinct and very different forms. We can clearly see why the organic remains of closely consecutive formations are more closely allied to each other, than are those of remote formations; for the forms are more closely linked together by generation: we can clearly see why the remains of an intermediate formation are intermediate in character.

The inhabitants of each successive period in the world's history have beaten their predecessors in the race for life, and are, in so far, higher in the scale of nature; and this may account for that vague yet ill-defined sentiment, felt by many palaeontologists, that organisation on the whole has progressed. If it should hereafter be proved that ancient animals resemble to a certain extent the embryos of more recent animals of the same class, the fact will be intelligible. The succession of the same types of structure within the same areas during the later geological periods ceases to be mysterious, and is simply explained by inheritance.

If then the geological record be as imperfect as I believe it to be, and it may at least be asserted that the record cannot be proved to be much more perfect, the main objections to the theory of natural selection are greatly diminished or disappear. On the other hand, all the chief laws of palaeontology plainly proclaim, as it seems to me, that species have been produced by ordinary generation: old forms having been supplanted by new and improved forms of life, produced by the laws of variation still acting round us, and preserved by Natural Selection. 

In considering the distribution of organic beings over the face of the globe, the first great fact which strikes us is, that neither the similarity nor the dissimilarity of the inhabitants of various regions can be accounted for by their climatal and other physical conditions. Of late, almost every author who has studied the subject has come to this conclusion. The case of America alone would almost suffice to prove its truth: for if we exclude the northern parts where the circumpolar land is almost continuous, all authors agree that one of the most fundamental divisions in geographical distribution is that between the New and Old Worlds; yet if we travel over the vast American continent, from the central parts of the United States to its extreme southern point, we meet with the most diversified conditions; the most humid districts, arid deserts, lofty mountains, grassy plains, forests, marshes, lakes, and great rivers, under almost every temperature. There is hardly a climate or condition in the Old World which cannot be paralleled in the New at least as closely as the same species generally require; for it is a most rare case to find a group of organisms confined to any small spot, having conditions peculiar in only a slight degree; for instance, small areas in the Old World could be pointed out hotter than any in the New World, yet these are not inhabited by a peculiar fauna or flora. Notwithstanding this parallelism in the conditions of the Old and New Worlds, how widely different are their living productions!

In the southern hemisphere, if we compare large tracts of land in Australia, South Africa, and western South America, between latitudes 25° and 35°, we shall find parts extremely similar in all their conditions, yet it would not be possible to point out three faunas and floras more utterly dissimilar. Or again we may compare the productions of South America south of lat. 35° with those north of 25°, which consequently inhabit a considerably different climate, and they will be found incomparably more closely related to each other, than they are to the productions of Australia or Africa under nearly the same climate. Analogous facts could be given with respect to the inhabitants of the sea.

A second great fact which strikes us in our general review is, that barriers of any kind, or obstacles to free migration, are related in a close and important manner to the differences between the productions of various regions. We see this in the great difference of nearly all the terrestrial productions of the New and Old Worlds, excepting in the northern parts, where the land almost joins, and where, under a slightly different climate, there might have been free migration for the northern temperate forms, as there now is for the strictly arctic productions. We see the same fact in the great difference between the inhabitants of Australia, Africa, and South America under the same latitude: for these countries are almost as much isolated from each other as is possible. On each continent, also, we see the same fact; for on the opposite sides of lofty and continuous mountain-ranges, and of great deserts, and sometimes even of large rivers, we find different productions; though as mountain chains, deserts, &c., are not as impassable, or likely to have endured so long as the oceans separating continents, the differences are very inferior in degree to those characteristic of distinct continents.

Turning to the sea, we find the same law. No two marine faunas are more distinct, with hardly a fish, shell, or crab in common, than those of the eastern and western shores of South and Central America; yet these great faunas are separated only by the narrow, but impassable, isthmus of panama. Westward of the shores of America, a wide space of open ocean extends, with not an island as a halting-place for emigrants; here we have a barrier of another kind, and as soon as this is passed we meet in the eastern islands of the Pacific, with another and totally distinct fauna. So that here three marine faunas range far northward and southward, in parallel lines not far from each other, under corresponding climates; but from being separated from each other by impassable barriers, either of land or open sea, they are wholly distinct. On the other hand, proceeding still further westward from the eastern islands of the tropical parts of the Pacific, we encounter no impassable barriers, and we have innumerable islands as halting-places, until after travelling over a hemisphere we come to the shores of Africa; and over this vast space we meet with no well-defined and distinct marine faunas. Although hardly one shell, crab or fish is common to the above-named three approximate faunas of Eastern and Western America and the eastern Pacific islands, yet many fish range from the Pacific into the Indian Ocean, and many shells are common to the eastern islands of the Pacific and the eastern shores of Africa, on almost exactly opposite meridians of longitude.

A third great fact, partly included in the foregoing statements, is the affinity of the productions of the same continent or sea, though the species themselves are distinct at different points and stations. It is a law of the widest generality, and every continent offers innumerable instances. Nevertheless the naturalist in travelling, for instance, from north to south never fails to be struck by the manner in which successive groups of beings, specifically distinct, yet clearly related, replace each other. He hears from closely allied, yet distinct kinds of birds, notes nearly similar, and sees their nests similarly constructed, but not quite alike, with eggs coloured in nearly the same manner. The plains near the Straits of Magellan are inhabited by one species of Rhea (American ostrich), and northward the plains of La Plata by another species of the same genus; and not by a true ostrich or emeu, like those found in Africa and Australia under the same latitude. On these same plains of La Plata, we see the agouti and bizcacha, animals having nearly the same habits as our hares and rabbits and belonging to the same order of Rodents, but they plainly display an American type of structure. We ascend the lofty peaks of the Cordillera and we find an alpine species of bizcacha; we look to the waters, and we do not find the beaver or musk-rat, but the coypu and capybara, rodents of the American type. Innumerable other instances could be given. If we look to the islands off the American shore, however much they may differ in geological structure, the inhabitants, though they may be all peculiar species, are essentially American. We may look back to past ages, as shown in the last chapter, and we find American types then prevalent on the American continent and in the American seas. We see in these facts some deep organic bond, prevailing throughout space and time, over the same areas of land and water, and independent of their physical conditions. The naturalist must feel little curiosity, who is not led to inquire what this bond is.

This bond, on my theory, is simply inheritance, that cause which alone, as far as we positively know, produces organisms quite like, or, as we see in the case of varieties nearly like each other. The dissimilarity of the inhabitants of different regions may be attributed to modification through natural selection, and in a quite subordinate degree to the direct influence of different physical conditions. The degree of dissimilarity will depend on the migration of the more dominant forms of life from one region into another having been effected with more or less ease, at periods more or less remote; on the nature and number of the former immigrants; -- and on their action and reaction, in their mutual struggles for life; the relation of organism to organism being, as I have already often remarked, the most important of all relations. Thus the high importance of barriers comes into play by checking migration; as does time for the slow process of modification through natural selection. Widely-ranging species, abounding in individuals, which have already triumphed over many competitors in their own widely-extended homes will have the best chance of seizing on new places, when they spread into new countries. In their new homes they will be exposed to new conditions, and will frequently undergo further modification and improvement; and thus they will become still further victorious, and will produce groups of modified descendants. On this principle of inheritance with modification, we can understand how it is that sections of genera, whole genera, and even families are confined to the same areas, as is so commonly and notoriously the case.

I believe, as was remarked in the last chapter, in no law of necessary development. As the variability of each species is an independent property, and will be taken advantage of by natural selection, only so far as it profits the individual in its complex struggle for life, so the degree of modification in different species will be no uniform quantity. If, for instance, a number of species, which stand in direct competition with each other, migrate in a body into a new and afterwards isolated country, they will be little liable to modification; for neither migration nor isolation in themselves can do anything. These principles come into play only by bringing organisms into new relations with each other, and in a lesser degree with the surrounding physical conditions. As we have seen in the last chapter that some forms have retained nearly the same character from an enormously remote geological period, so certain species have migrated over vast spaces, and have not become greatly modified.

On these views, it is obvious, that the several species of the same genus, though inhabiting the most distant quarters of the world, must originally have proceeded from the same source, as they have descended from the same progenitor. In the case of those species, which have undergone during whole geological periods but little modification, there is not much difficulty in believing that they may have migrated from the same region; for during the vast geographical and climatal changes which will have supervened since ancient times, almost any amount of migration is possible. But in many other cases, in which we have reason to believe that the species of a genus have been produced within comparatively recent times, there is great difficulty on this head. It is also obvious that the individuals of the same species, though now inhabiting distant and isolated regions, must have proceeded from one spot, where their parents were first produced: for, as explained in the last chapter, it is incredible that individuals identically the same should ever have been produced through natural selection from parents specifically distinct.

We are thus brought to the question which has been largely discussed by naturalists, namely, whether species have been created at one or more points of the earth's surface. Undoubtedly there are very many cases of extreme difficulty, in understanding how the same species could possibly have migrated from some one point to the several distant and isolated points, where now found. Nevertheless the simplicity of the view that each species was first produced within a single region captivates the mind. He who rejects it, rejects the vera causa of ordinary generation with subsequent migration, and calls in the agency of a miracle. It is universally admitted, that in most cases the area inhabited by a species is continuous; and when a plant or animal inhabits two points so distant from each other, or with an interval of such a nature, that the space could not be easily passed over by migration, the fact is given as something remarkable and exceptional. The capacity of migrating across the sea is more distinctly limited in terrestrial mammals, than perhaps in any other organic beings; and, accordingly, we find no inexplicable cases of the same mammal inhabiting distant points of the world. No geologist will feel any difficulty in such cases as Great Britain having been formerly united to Europe, and consequently possessing the same quadrupeds. But if the same species can be produced at two separate points, why do we not find a single mammal common to Europe and Australia or South America? The conditions of life are nearly the same, so that a multitude of European animals and plants have become naturalised in America and Australia; and some of the aboriginal plants are identically the same at these distant points of the northern and southern hemispheres? The answer, as I believe, is, that mammals have not been able to migrate, whereas some plants, from their varied means of dispersal, have migrated across the vast and broken interspace. The great and striking influence which barriers of every kind have had on distribution, is intelligible only on the view that the great majority of species have been produced on one side alone, and have not been able to migrate to the other side. Some few families, many sub-families, very many genera, and a still greater number of sections of genera are confined to a single region; and it has been observed by several naturalists, that the most natural genera, or those genera in which the species are most closely related to each other, are generally local, or confined to one area. What a strange anomaly it would be, if, when coming one step lower in the series, to the individuals of the same species, a directly opposite rule prevailed; and species were not local, but had been produced in two or more distinct areas!

Hence it seems to me, as it has to many other naturalists, that the view of each species having been produced in one area alone, and having subsequently migrated from that area as far as its powers of migration and subsistence under past and present conditions permitted, is the most probable. Undoubtedly many cases occur, in which we cannot explain how the same species could have passed from one point to the other. But the geographical and climatal changes, which have certainly occurred within recent geological times, must have interrupted or rendered discontinuous the formerly continuous range of many species. So that we are reduced to consider whether the exceptions to continuity of range are so numerous and of so grave a nature, that we ought to give up the belief, rendered probable by general considerations, that each species has been produced within one area, and has migrated thence as far as it could. It would be hopelessly tedious to discuss all the exceptional cases of the same species, now living at distant and separated points; nor do I for a moment pretend that any explanation could be offered of many such cases. But after some preliminary remarks, I will discuss a few of the most striking classes of facts; namely, the existence of the same species on the summits of distant mountain-ranges, and at distant points in the arctic and antarctic regions; and secondly (in the following chapter), the wide distribution of freshwater productions; and thirdly, the occurrence of the same terrestrial species on islands and on the mainland, though separated by hundreds of miles of open sea. If the existence of the same species at distant and isolated points of the earth's surface, can in many instances be explained on the view of each species having migrated from a single birthplace; then, considering our ignorance with respect to former climatal and geographical changes and various occasional means of transport, the belief that this has been the universal law, seems to me incomparably the safest.

In discussing this subject, we shall be enabled at the same time to consider a point equally important for us, namely, whether the several distinct species of a genus, which on my theory have all descended from a common progenitor, can have migrated (undergoing modification during some part of their migration) from the area inhabited by their progenitor. If it can be shown to be almost invariably the case, that a region, of which most of its inhabitants are closely related to, or belong to the same genera with the species of a second region, has probably received at some former period immigrants from this other region, my theory will be strengthened; for we can clearly understand, on the principle of modification, why the inhabitants of a region should be related to those of another region, whence it has been stocked. A volcanic island, for instance, upheaved and formed at the distance of a few hundreds of miles from a continent, would probably receive from it in the course of time a few colonists, and their descendants, though modified, would still be plainly related by inheritance to the inhabitants of the continent. Cases of this nature are common, and are, as we shall hereafter more fully see, inexplicable on the theory of independent creation. This view of the relation of species in one region to those in another, does not differ much (by substituting the word variety for species) from that lately advanced in an ingenious paper by Mr Wallace, in which he concludes, that `every species has come into existence coincident both in space and time with a pre-existing closely allied species.' And I now know from correspondence, that this coincidence he attributes to generation with modification.

The previous remarks on `single and multiple centres of creation' do not directly bear on another allied question, namely whether all the individuals of the same species have descended from a single pair, or single hermaphrodite, or whether, as some authors suppose, from many individuals simultaneously created. With those organic beings which never intercross (if such exist), the species, on my theory, must have descended from a succession of improved varieties, which will never have blended with other individuals or varieties, but will have supplanted each other; so that, at each successive stage of modification and improvement, all the individuals of each variety will have descended from a single parent. But in the majority of cases, namely, with all organisms which habitually unite for each birth, or which often intercross, I believe that during the slow process of modification the individuals of the species will have been kept nearly uniform by intercrossing; so that many individuals will have gone on simultaneously changing, and the whole amount of modification will not have been due, at each stage, to descent from a single parent. To illustrate what I mean: our English racehorses differ slightly from the horses of every other breed; but they do not owe their difference and superiority to descent from any single pair, but to continued care in selecting and training many individuals during many generations.

Before discussing the three classes of facts, which I have selected as presenting the greatest amount of difficulty on the theory of `single centres of creation,' I must say a few words on the means of dispersal.

Means of Dispersal

Sir C. Lyell and other authors have ably treated this subject. I can give here only the briefest abstract of the more important facts. Change of climate must have had a powerful influence on migration: a region when its climate was different may have been a high road for migration, but now be impassable; I shall, however, presently have to discuss this branch of the subject in some detail. Changes of level in the land must also have been highly influential: a narrow isthmus now separates two marine faunas; submerge it, or let it formerly have been submerged, and the two faunas will now blend or may formerly have blended: where the sea now extends, land may at a former period have connected islands or possibly even continents together, and thus have allowed terrestrial productions to pass from one to the other. No geologist will dispute that great mutations of level have occurred within the period of existing organisms. Edward Forbes insisted that all the islands in the Atlantic must recently have been connected with Europe or Africa, and Europe likewise with America. Other authors have thus hypothetically bridged over every ocean, and have united almost every island to some mainland. If indeed the arguments used by Forbes are to be trusted, it must be admitted that scarcely a single island exists which has not recently been united to some continent. This view cuts the Gordian knot of the dispersal of the same species to the most distant points, and removes many a difficulty: but to the best of any judgement we are not authorised in admitting such enormous geographical changes within the period of existing species. It seems to me that we have abundant evidence of great oscillations of level in our continents; but not of such vast changes in their position and extension, as to have united them within the recent period to each other and to the several intervening oceanic islands. I freely admit the former existence of many islands, now buried beneath the sea, which may have served as halting places for plants and for many animals during their migration. In the coral-producing oceans such sunken islands are now marked, as I believe, by rings of coral or atolls standing over them. Whenever it is fully admitted, as I believe it will some day be, that each species has proceeded from a single birthplace, and when in the course of time we know something definite about the means of distribution, we shall be enabled to speculate with security on the former extension of the land. But I do not believe that it will ever be proved that within the recent period continents which are now quite separate, have been continuously, or almost continuously, united with each other, and with the many existing oceanic islands. Several facts in distribution, such as the great difference in the marine faunas on the opposite sides of almost every continent, the close relation of the tertiary inhabitants of several lands and even seas to their present inhabitants, a certain degree of relation (as we shall hereafter see) between the distribution of mammals and the depth of the sea, these and other such facts seem to me opposed to the admission of such prodigious geographical revolutions within the recent period, as are necessitated in the view advanced by Forbes and admitted by his many followers. The nature and relative proportions of the inhabitants of oceanic islands likewise seem to me opposed to the belief of their former continuity with continents. Nor does their almost universally volcanic composition favour the admission that they are the wrecks of sunken continents; if they had originally existed as mountain-ranges on the land, some at least of the islands would have been formed, like other mountain-summits, of granite, metamorphic schists, old fossiliferous or other such rocks, instead of consisting of mere piles of volcanic matter.

I must now say a few words on what are called accidental means, but which more properly might be called occasional means of distribution. I shall here confine myself to plants. In botanical works, this or that plant is stated to be ill adapted for wide dissemination; but for transport across the sea, the greater or less facilities may be said to be almost wholly unknown. Until I tried, with Mr Berkeley's aid, a few experiments, it was not even known how far seeds could resist the injurious action of sea-water. To my surprise I found that out of 87 kinds, 64 germinated after an immersion of 28 days, and a few survived an immersion of 137 days. For convenience sake I chiefly tried small seeds, without the capsule or fruit; and as all of these sank in a few days, they could not be floated across wide spaces of the sea, whether or not they were injured by the salt-water. Afterwards I tried some larger fruits, capsules, &c., and some of these floated for a long time. It is well known what a difference there is in the buoyancy of green and seasoned timber; and it occurred to me that floods might wash down plants or branches, and that these might be dried on the banks, and then by a fresh rise in the stream be washed into the sea. Hence I was led to dry stems and branches of 94 plants with ripe fruit, and to place them on sea water. The majority sank quickly, but some which whilst green floated for a very short time, when dried floated much longer; for instance, ripe hazel-nuts sank immediately, but when dried, they floated for 90 days and afterwards when planted they germinated; an asparagus plant with ripe berries floated for 23 days, when dried it floated for 85 days, and the seeds afterwards germinated: the ripe seeds of Helosciadium sank in two days, when dried they floated for above 90 days, and afterwards germinated. Altogether out of the 94 dried plants, 18 floated for above 28 days, and some of the 18 floated for a very much longer period. So that as 64/87 seeds germinated after an immersion of 28 days; and as 18/94 plants with ripe fruit (but not all the same species as in the foregoing experiment) floated, after being dried, for above 28 days, as far as we may infer anything from these scanty facts, we may conclude that the seeds of 14/100 plants of any country might be floated by sea-currents during 28 days, and would retain their power of germination. In Johnston's physical Atlas, the average rate of the several Atlantic currents is 33 miles per diem (some currents running at the rate of 60 miles per diem); on this average, the seeds of 14/100 plants belonging to one country might be floated across 924 miles of sea to another country; and when stranded, if blown to a favourable spot by an inland gale, they would germinate.

Subsequently to my experiments, M. Martens tried similar ones, but in a much better manner, for he placed the seeds in a box in the actual sea, so that they were alternately wet and exposed to the air like really floating plants. He tried 98 seeds, mostly different from mine; but he chose many large fruits and likewise seeds from plants which live near the sea; and this would have favoured the average length of their flotation and of their resistance to the injurious action of the salt-water. On the other hand he did not previously dry the plants or branches with the fruit; and this, as we have seen, would have caused some of them to have floated much longer. The result was that 18/98 of his seeds floated for 42 days, and were then capable of germination. But I do not doubt that plants exposed to the waves would float for a less time than those protected from violent movement as in our experiments. Therefore it would perhaps be safer to assume that the seeds of about 10/100 plants of a flora, after having been dried, could be floated across a space of sea 900 miles in width, and would then germinate. The fact of the larger fruits often floating longer than the small, is interesting; as plants with large seeds or fruit could hardly be transported by any other means; and Alph. de Candolle has shown that such plants generally have restricted ranges.

But seeds may be occasionally transported in another manner. Drift timber is thrown up on most islands, even on those in the midst of the widest oceans; and the natives of the coral-islands in the Pacific, procure stones for their tools, solely from the roots of drifted trees, these stones being a valuable royal tax. I find on examination, that when irregularly shaped stones are embedded in the roots of trees, small parcels of earth are very frequently enclosed in their interstices and behind them, so perfectly that not a particle could be washed away in the longest transport: out of one small portion of earth thus completely enclosed by wood in an oak about 50 years old, three dicotyledonous plants germinated: I am certain of the accuracy of this observation. Again, I can show that the carcasses of birds, when floating on the sea, sometimes escape being immediately devoured; and seeds of many kinds in the crops of floating birds long retain their vitality: peas and vetches, for instance, are killed by even a few days' immersion in sea-water; but some taken out of the crop of a pigeon, which had floated on artificial salt-water for 30 days, to my surprise nearly all germinated.

Living birds can hardly fail to be highly effective agents in the transportation of seeds. I could give many facts showing how frequently birds of many kinds are blown by gales to vast distances across the ocean. We may I think safely assume that under such circumstances their rate of flight would often be 35 miles an hour; and some authors have given a far higher estimate. I have never seen an instance of nutritious seeds passing through the intestines of a bird; but hard seeds of fruit will pass uninjured through even the digestive organs of a turkey. In the course of two months, I picked up in my garden 12 kinds of seeds, out of the excrement of small birds, and these seemed perfect, and some of them, which I tried, germinated. But the following fact is more important: the crops of birds do not secrete gastric juice, and do not in the least injure, as I know by trial, the germination of seeds; now after a bird has found and devoured a large supply of food, it is positively asserted that all the grains do not pass into the gizzard for 12 or even 18 hours. A bird in this interval might easily be blown to the distance of 500 miles, and hawks are known to look out for tired birds, and the contents of their torn crops might thus readily get scattered. Mr Brent informs me that a friend of his had to give up flying carrier-pigeons from France to England, as the hawks on the English coast destroyed so many on their arrival. Some hawks and owls bolt their prey whole, and after an interval of from twelve to twenty hours, disgorge pellets, which, as I know from experiments made in the Zoological Gardens, include seeds capable of germination. Some seeds of the oat, wheat, millet, canary, hemp, clover, and beet germinated after having been from twelve to twenty-one hours in the stomachs of different birds of prey; and two seeds of beet grew after having been thus retained for two days and fourteen hours. Freshwater fish, I find, eat seeds of many land and water plants: fish are frequently devoured by birds, and thus the seeds might be transported from place to place. I forced many kinds of seeds into the stomachs of dead fish, and then gave their bodies to fishing-eagles, storks, and pelicans; these birds after an interval of many hours, either rejected the seeds in pellets or passed them in their excrement; and several of these seeds retained their power of germination. Certain seeds, however, were always killed by this process.

Although the beaks and feet of birds are generally quite clean, I can show that earth sometimes adheres to them: in one instance I removed twenty-two grains of dry argillaceous earth from one foot of a partridge, and in this earth there was a pebble quite as large as the seed of a vetch. Thus seeds might occasionally be transported to great distances; for many facts could be given showing that soil almost everywhere is charged with seeds. Reflect for a moment on the millions of quails which annually cross the Mediterranean; and can we doubt that the earth adhering to their feet would sometimes include a few minute seeds? But I shall presently have to recur to this subject.

As icebergs are known to be sometimes loaded with earth and stones, and have even carried brushwood, bones, and the nest of a land-bird, I can hardly doubt that they must occasionally have transported seeds from one part to another of the arctic and antarctic regions, as suggested by Lyell; and during the Glacial period from one part of the now temperate regions to another. In the Azores, from the large number of the species of plants common to Europe, in comparison with the plants of other oceanic islands nearer to the mainland, and (as remarked by Mr H. C. Watson) from the somewhat northern character of the flora in comparison with the latitude, I suspected that these islands had been partly stocked by ice-borne seeds, during the Glacial epoch. At my request Sir C. Lyell wrote to M. Hartung to inquire whether he had observed erratic boulders on these islands, and he answered that he had found large fragments of granite and other rocks, which do not occur in the archipelago. Hence we may safely infer that icebergs formerly landed their rocky burthens on the shores of these mid-ocean islands, and it is at least possible that they may have brought thither the seeds of northern plants.

Considering that the several above means of transport, and that several other means, which without doubt remain to be discovered, have been in action year after year, for centuries and tens of thousands of years, it would I think be a marvellous fact if many plants had not thus become widely transported. These means of transport are sometimes called accidental, but this is not strictly correct: the currents of the sea are not accidental, nor is the direction of prevalent gales of wind. It should be observed that scarcely any means of transport would carry seeds for very great distances; for seeds do not retain their vitality when exposed for a great length of time to the action of seawater; nor could they be long carried in the crops or intestines of birds. These means, however, would suffice for occasional transport across tracts of sea some hundred miles in breadth, or from island to island, or from a continent to a neighbouring island, but not from one distant continent to another. The floras of distant continents would not by such means become mingled in any great degree; but would remain as distinct as we now see them to be. The currents, from their course, would never bring seeds from North America to Britain, though they might and do bring seeds from the West Indies to our western shores, where, if not killed by so long an immersion in salt-water, they could not endure our climate. Almost every year, one or two land-birds are blown across the whole Atlantic Ocean, from North America to the western shores of Ireland and England; but seeds could be transported by these wanderers only by one means, namely, in dirt sticking to their feet, which is in itself a rare accident. Even in this case, how small would the chance be of a seed falling on favourable soil, and coming to maturity! But it would be a great error to argue that because a well-stocked island, like Great Britain, has not, as far as is known (and it would be very difficult to prove this), received within the last few centuries, through occasional means of transport, immigrants from Europe or any other continent, that a poorly-stocked island, though standing more remote from the mainland, would not receive colonists by similar means. I do not doubt that out of twenty seeds or animals transported to an island, even if far less well-stocked than Britain, scarcely more than one would be so well fitted to its new home, as to become naturalised. But this, as it seems to me, is no valid argument against what would be effected by occasional means of transport, during the long lapse of geological time, whilst an island was being upheaved and formed, and before it had become fully stocked with inhabitants. On almost bare land, with few or no destructive insects or birds living there, nearly every seed, which chanced to arrive, would be sure to germinate and survive.
Dispersal during the Glacial period

The identity of many plants and animals, on mountain-summits, separated from each other by hundreds of miles of lowlands, where the Alpine species could not possibly exist, is one of the most striking cases known of the same species living at distant points, without the apparent possibility of their having migrated from one to the other. It is indeed a remarkable fact to see so many of the same plants living on the snowy regions of the Alps or Pyrenees, and in the extreme northern parts of Europe; but it is far more remarkable, that the plants on the White Mountains, in the United States of America, are all the same with those of Labrador, and nearly all the same, as we hear from Asa Gray, with those on the loftiest mountains of Europe. Even as long ago as 1747, such facts led Gmelin to conclude that the same species must have been independently created at several distinct points; and we might have remained in this same belief, had not Agassiz and others called vivid attention to the Glacial period, which, as we shall immediately see, affords a simple explanation of these facts. We have evidence of almost every conceivable kind, organic and inorganic, that within a very recent geological period, central Europe and North America suffered under an Arctic climate. The ruins of a house burnt by fire do not tell their tale more plainly, than do the mountains of Scotland and Wales, with their scored flanks, polished surfaces, and perched boulders, of the icy streams with which their valleys were lately filled. So greatly has the climate of Europe changed, that in Northern Italy, gigantic moraines, left by old glaciers, are now clothed by the vine and maize. Throughout a large part of the United States, erratic boulders, and rocks scored by drifted icebergs and coast-ice, plainly reveal a former cold period.

The former influence of the glacial climate on the distribution of the inhabitants of Europe, as explained with remarkable clearness by Edward Forbes, is substantially as follows. But we shall follow the changes more readily, by supposing a new glacial period to come slowly on, and then pass away, as formerly occurred. As the cold came on, and as each more southern zone became fitted for arctic beings and ill-fitted for their former more temperate inhabitants, the latter would be supplanted and arctic productions would take their places. The inhabitants of the more temperate regions would at the same time travel southward, unless they were stopped by barriers, in which case they would perish. The mountains would become covered with snow and ice, and their former Alpine inhabitants would descend to the plains. By the time that the cold had reached its maximum, we should have a uniform arctic fauna and flora, covering the central parts of Europe, as far south as the Alps and Pyrenees, and even stretching into Spain. The now temperate regions of the United States would likewise be covered by arctic plants and animals, and these would be nearly the same with those of Europe; for the present circumpolar inhabitants, which we suppose to have everywhere travelled southward, are remarkably uniform round the world. We may suppose that the Glacial period came on a little earlier or later in North America than in Europe, so will the southern migration there have been a little earlier or later; but this will make no difference in the final result.

As the warmth returned, the arctic forms would retreat northward, closely followed up in their retreat by the productions of the more temperate regions. And as the snow melted from the bases of the mountains, the arctic forms would seize on the cleared and thawed ground, always ascending higher and higher, as the warmth increased, whilst their brethren were pursuing their northern journey. Hence, when the warmth had fully returned, the same arctic species, which had lately lived in a body together on the lowlands of the Old and New Worlds, would be left isolated on distant mountain-summits (having been exterminated on all lesser heights) and in the arctic regions of both hemispheres.

Thus we can understand the identity of many plants at points so immensely remote as on the mountains of the United States and of Europe. We can thus also understand the fact that the Alpine plants of each mountain-range are more especially related to the arctic forms living due north or nearly due north of them: for the migration as the cold came on, and the re-migration on the returning warmth, will generally have been due south and north. The Alpine plants, for example, of Scotland, as remarked by Mr H. C. Watson, and those of the Pyrenees, as remarked by Ramond, are more especially allied to the plants of northern Scandinavia; those of the United States to Labrador; those of the mountains of Siberia to the arctic regions of that country. These views, grounded as they are on the perfectly well-ascertained occurrence of a former Glacial period, seem to me to explain in so satisfactory a manner the present distribution of the Alpine and Arctic productions of Europe and America, that when in other regions we find the same species on distant mountain-summits, we may almost conclude without other evidence, that a colder climate permitted their former migration across the low intervening tracts, since become too warm for their existence.

If the climate, since the Glacial period, has ever been in any degree warmer than at present (as some geologists in the United States believe to have been the case, chiefly from the distribution of the fossil Gnathodon), then the arctic and temperate productions will at a very late period have marched a little further north, and subsequently have retreated to their present homes; but I have met with no satisfactory evidence with respect to this intercalated slightly warmer period, since the Glacial period.

The arctic forms, during their long southern migration and re-migration northward, will have been exposed to nearly the same climate, and, as is especially to be noticed, they will have kept in a body together; consequently their mutual relations will not have been much disturbed, and, in accordance with the principles inculcated in this volume, they will not have been liable to much modification. But with our Alpine productions, left isolated from the moment of the returning warmth, first at the bases and ultimately on the summits of the mountains, the case will have been somewhat different; for it is not likely that all the same arctic species will have been left on mountain ranges distant from each other, and have survived there ever since; they will, also, in all probability have become mingled with ancient Alpine species, which must have existed on the mountains before the commencement of the Glacial epoch, and which during its coldest period will have been temporarily driven down to the plains; they will, also, have been exposed to somewhat different climatal influences. Their mutual relations will thus have been in some degree disturbed; consequently they will have been liable to modification; and this we find has been the case; for if we compare the present Alpine plants and animals of the several great European mountain-ranges, though very many of the species are identically the same, some present varieties, some are ranked as doubtful forms, and some few are distinct yet closely allied or representative species.

In illustrating what, as I believe, actually took place during the Glacial period, I assumed that at its commencement the arctic productions were as uniform round the polar regions as they are at the present day. But the foregoing remarks on distribution apply not only to strictly arctic forms, but also to many sub-arctic and to some few northern temperate forms, for some of these are the same on the lower mountains and on the plains of North America and Europe; and it may be reasonably asked how I account for the necessary degree of uniformity of the sub-arctic and northern temperate forms round the world, at the commencement of the Glacial period. At the present day, the sub-arctic and northern temperate productions of the Old and New Worlds are separated from each other by the Atlantic Ocean and by the extreme northern part of the Pacific. During the Glacial period, when the inhabitants of the Old and New Worlds lived further southwards than at present, they must have been still more completely separated by wider spaces of ocean. I believe the above difficulty may be surmounted by looking to still earlier changes of climate of an opposite nature. We have good reason to believe that during the newer Pliocene period, before the Glacial epoch, and whilst the majority of the inhabitants of the world were specifically the same as now, the climate was warmer than at the present day. Hence we may suppose that the organisms now living under the climate of latitude 60°, during the Pliocene period lived further north under the Polar Circle, in latitude 66°-67°; and that the strictly arctic productions then lived on the broken land still nearer to the pole. Now if we look at a globe, we shall see that under the Polar Circle there is almost continuous land from western Europe, through Siberia, to eastern America. And to this continuity of the circumpolar land, and to the consequent freedom for intermigration under a more favourable climate, I attribute the necessary amount of uniformity in the sub-arctic and northern temperate productions of the Old and New Worlds, at a period anterior to the Glacial epoch.

Believing, from reasons before alluded to, that our continents have long remained in nearly the same relative position, though subjected to large, but partial oscillations of level, I am strongly inclined to extend the above view, and to infer that during some earlier and still warmer period, such as the older Pliocene period, a large number of the same plants and animals inhabited the almost continuous circumpolar land; and that these plants and animals, both in the Old and New Worlds, began slowly to migrate southwards as the climate became less warm, long before the commencement of the Glacial period. We now see, as I believe, their descendants, mostly in a modified condition, in the central parts of Europe and the United States. On this view we can understand the relationship, with very little identity, between the productions of North America and Europe, a relationship which is most remarkable, considering the distance of the two areas, and their separation by the Atlantic Ocean. We can further understand the singular fact remarked on by several observers, that the productions of Europe and America during the later tertiary stages were more closely related to each other than they are at the present time; for during these warmer periods the northern parts of the Old and New Worlds will have been almost continuously united by land, serving as a bridge, since rendered impassable by cold, for the inter-migration of their inhabitants.

During the slowly decreasing warmth of the Pliocene period, as soon as the species in common, which inhabited the New and Old Worlds, migrated south of the Polar Circle, they must have been completely cut off from each other. This separation, as far as the more temperate productions are concerned, took place long ages ago. And as the plants and animals migrated southward, they will have become mingled in the one great region with the native American productions, and have had to compete with them; and in the other great region, with those of the Old World. Consequently we have here everything favourable for much modification, for far more modification than with the Alpine productions, left isolated, within a much more recent period, on the several mountain-ranges and on the arctic lands of the two Worlds. Hence it has come, that when we compare the now living productions of the temperate regions of the New and Old Worlds, we find very few identical species (though Asa Gray has lately shown that more plants are identical than was formerly supposed), but we find in every great class many forms, which some naturalists rank as geographical races, and others as distinct species; and a host of closely allied or representative forms which are ranked by all naturalists as specifically distinct.

As on the land, so in the waters of the sea, a slow southern migration of a marine fauna, which during the Pliocene or even a somewhat earlier period, was nearly uniform along the continuous shores of the Polar Circle, will account, on the theory of modification, for many closely allied forms now living in areas completely sundered. Thus, I think, we can understand the presence of many existing and tertiary representative forms on the eastern and western shores of temperate North America; and the still more striking case of many closely allied crustaceans (as described in Dana's admirable work), of some fish and other marine animals, in the Mediterranean and in the seas of Japan, areas now separated by a continent and by nearly a hemisphere of equatorial ocean.

These cases of relationship, without identity, of the inhabitants of seas now disjoined, and likewise of the past and present inhabitants of the temperate lands of North America and Europe, are inexplicable on the theory of creation. We cannot say that they have been created alike, in correspondence with the nearly similar physical conditions of the areas; for if we compare, for instance, certain parts of South America with the southern continents of the Old World, we see countries closely corresponding in all their physical conditions, but with their inhabitants utterly dissimilar.

But we must return to our more immediate subject, the Glacial period. I am convinced that Forbes's view may be largely extended. In Europe we have the plainest evidence of the cold period, from the western shores of Britain to the Oural range, and southward to the Pyrenees. We may infer, from the frozen mammals and nature of the mountain vegetation, that Siberia was similarly affected. Along the Himalaya, at points 900 miles apart, glaciers have left the marks of their former low descent; and in Sikkim, Dr Hooker saw maize growing on gigantic ancient moraines. South of the equator, we have some direct evidence of former glacial action in New Zealand; and the same plants, found on widely separated mountains in this island, tell the same story. If one account which has been published can be trusted, we have direct evidence of glacial action in the southeastern corner of Australia.

Looking to America; in the northern half, ice-borne fragments of rock have been observed on the eastern side as far south as lat. 36°-37°, and on the shores of the Pacific, where the climate is now so different, as far south as lat. 46°; erratic boulders have, also, been noticed on the Rocky Mountains. In the Cordillera of Equatorial South America, glaciers once extended far below their present level. In central Chile I was astonished at the structure of a vast mound of detritus, about 800 feet in height, crossing a valley of the Andes; and this I now feel convinced was a gigantic moraine, left far below any existing glacier. Further south on both sides of the continent, from lat. 41° to the southernmost extremity, we have the clearest evidence of former glacial action, in huge boulders transported far from their parent source.

We do not know that the Glacial epoch was strictly simultaneous at these several far distant points on opposite sides of the world. But we have good evidence in almost every case, that the epoch was included within the latest geological period. We have, also, excellent evidence, that it endured for an enormous time, as measured by years, at each point. The cold may have come on, or have ceased, earlier at one point of the globe than at another, but seeing that it endured for long at each, and that it was contemporaneous in a geological sense, it seems to me probable that it was, during a part at least of the period, actually simultaneous throughout the world. Without some distinct evidence to the contrary, we may at least admit as probable that the glacial action was simultaneous on the eastern and western sides of North America, in the Cordillera under the equator and under the warmer temperate zones, and on both sides of the southern extremity of the continent. If this be admitted, it is difficult to avoid believing that the temperature of the whole world was at this period simultaneously cooler. But it would suffice for my purpose, if the temperature was at the same time lower along certain broad belts of longitude.

On this view of the whole world, or at least of broad longitudinal belts, having been simultaneously colder from pole to pole, much light can be thrown on the present distribution of identical and allied species. In America, Dr Hooker has shown that between forty and fifty of the flowering plants of Tierra del Fuego, forming no inconsiderable part of its scanty flora, are common to Europe, enormously remote as these two points are; and there are many closely allied species. On the lofty mountains of equatorial America a host of peculiar species belonging to European genera occur. On the highest mountains of Brazil, some few European genera were found by Gardner, which do not exist in the wide intervening hot countries. So on the Silla of Caraccas the illustrious Humboldt long ago found species belonging to genera characteristic of the Cordillera. On the mountains of Abyssinia, several European forms and some few representatives of the peculiar flora of the Cape of Good Hope occur. At the Cape of Good Hope a very few European species, believed not to have been introduced by man, and on the mountains, some few representative European forms are found, which have not been discovered in the intertropical parts of Africa. On the Himalaya, and on the isolated mountain-ranges of the peninsula of India, on the heights of Ceylon, and on the volcanic cones of Java, many plants occur, either identically the same or representing each other, and at the same time representing plants of Europe, not found in the intervening hot lowlands. A list of the genera collected on the loftier peaks of Java raises a picture of a collection made on a hill in Europe! Still more striking is the fact that southern Australian forms are clearly represented by plants growing on the summits of the mountains of Borneo. Some of these Australian forms, as I hear from Dr. Hooker, extend along the heights of the peninsula of Malacca, and are thinly scattered, on the one hand over India and on the other as far as Japan.

On the southern mountains of Australia, Dr. F. Müller has discovered several European species; other species, not introduced by man, occur on the lowlands; and a long list can be given, as I am informed by Dr. Hooker, of European genera, found in Australia, but not in the intermediate torrid regions. In the admirable `Introduction to the Flora of New Zealand,' by Dr. Hooker, analogous and striking facts are given in regard to the plants of that large island. Hence we see that throughout the world, the plants growing on the more lofty mountains, and on the temperate lowlands of the northern and southern hemispheres, are sometimes identically the same; but they are much oftener specifically distinct, though related to each other in a most remarkable manner.

This brief abstract applies to plants alone: some strictly analogous facts could be given on the distribution of terrestrial animals. In marine productions, similar cases occur; as an example, I may quote a remark by the highest authority, Prof. Dana, that `it is certainly a wonderful fact that New Zealand should have a closer resemblance in its crustacea to Great Britain, its antipode, than to any other part of the world.' Sir J. Richardson, also, speaks of the reappearance on the shores of New Zealand, Tasmania, &c., of northern forms of fish. Dr Hooker informs me that twenty-five species of Algae are common to New Zealand and to Europe, but have not been found in the intermediate tropical seas.

It should be observed that the northern species and forms found in the southern parts of the southern hemisphere, and on the mountain-ranges of the intertropical regions, are not arctic, but belong to the northern temperate zones. As Mr. H. C. Watson has recently remarked, `In receding from polar towards equatorial latitudes, the Alpine or mountain floras really become less and less arctic.' Many of the forms living on the mountains of the warmer regions of the earth and in the southern hemisphere are of doubtful value, being ranked by some naturalists as specifically distinct, by others as varieties; but some are certainly identical, and many, though closely related to northern forms, must be ranked as distinct species.

Now let us see what light can be thrown on the foregoing facts, on the belief, supported as it is by a large body of geological evidence, that the whole world, or a large part of it, was during the Glacial period simultaneously much colder than at present. The Glacial period, as measured by years, must have been very long; and when we remember over what vast spaces some naturalised plants and animals have spread within a few centuries, this period will have been ample for any amount of migration. As the cold came slowly on, all the tropical plants and other productions will have retreated from both sides towards the equator, followed in the rear by the temperate productions, and these by the arctic; but with the latter we are not now concerned. The tropical plants probably suffered much extinction; how much no one can say; perhaps formerly the tropics supported as many species as we see at the present day crowded together at the Cape of Good Hope, and in parts of temperate Australia. As we know that many tropical plants and animals can withstand a considerable amount of cold, many might have escaped extermination during a moderate fall of temperature, more especially by escaping into the warmest spots. But the great fact to bear in mind is, that all tropical productions will have suffered to a certain extent. On the other hand, the temperate productions, after migrating nearer to the equator, though they will have been placed under somewhat new conditions, will have suffered less. And it is certain that many temperate plants, if protected from the inroads of competitors, can withstand a much warmer climate than their own. Hence, it seems to me possible, bearing in mind that the tropical productions were in a suffering state and could not have presented a firm front against intruders, that a certain number of the more vigorous and dominant temperate forms might have penetrated the native ranks and have reached or even crossed the equator. The invasion would, of course, have been greatly favoured by high land, and perhaps by a dry climate; for Dr. Falconer informs me that it is the damp with the heat of the tropics which is so destructive to perennial plants from a temperate climate. On the other hand, the most humid and hottest districts will have afforded an asylum to the tropical natives. The mountain-ranges north-west of the Himalaya, and the long line of the Cordillera, seem to have afforded two great lines of invasion: and it is a striking fact, lately communicated to me by Dr. Hooker, that all the flowering plants, about forty-six in number, common to Tierra del Fuego and to Europe still exist in North America, which must have lain on the line of march. But I do not doubt that some temperate productions entered and crossed even the lowlands of the tropics at the period when the cold was most intense, when arctic forms had migrated some twenty-five degrees of latitude from their native country and covered the land at the foot of the Pyrenees. At this period of extreme cold, I believe that the climate under the equator at the level of the sea was about the same with that now felt there at the height of six or seven thousand feet. During this the coldest period, I suppose that large spaces of the tropical lowlands were clothed with a mingled tropical and temperate vegetation, like that now growing with strange luxuriance at the base of the Himalaya, as graphically described by Hooker.

Thus, as I believe, a considerable number of plants, a few terrestrial animals, and some marine productions, migrated during the Glacial period from the northern and southern temperate zones into the intertropical regions, and some even crossed the equator. As the warmth returned, these temperate forms would naturally ascend the higher mountains, being exterminated on the lowlands; those which had not reached the equator, would re-migrate northward or southward towards their former homes; but the forms, chiefly northern, which had crossed the equator, would travel still further from their homes into the more temperate latitudes of the opposite hemisphere. Although we have reason to believe from geological evidence that the whole body of arctic shells underwent scarcely any modification during their long southern migration and re-migration northward, the case may have been wholly different with those intruding forms which settled themselves on the intertropical mountains, and in the southern hemisphere. These being surrounded by strangers will have had to compete with many new forms of life; and it is probable that selected modifications in their structure, habits, and constitutions will have profited them. Thus many of these wanderers, though still plainly related by inheritance to their brethren of the northern or southern hemispheres, now exist in their new homes as well-marked varieties or as distinct species.

It is a remarkable fact, strongly insisted on by Hooker in regard to America, and by Alph. de Candolle in regard to Australia, that many more identical plants and allied forms have apparently migrated from the north to the south, than in a reversed direction. We see, however, a few southern vegetable forms on the mountains of Borneo and Abyssinia. I suspect that this preponderant migration from north to south is due to the greater extent of land in the north, and to the northern forms having existed in their own homes in greater numbers, and having consequently been advanced through natural selection and competition to a higher stage of perfection or dominating power, than the southern forms. And thus, when they became commingled during the Glacial period, the northern forms were enabled to beat the less powerful southern forms. Just in the same manner as we see at the present day, that very many European productions cover the ground in La Plata, and in a lesser degree in Australia, and have to a certain extent beaten the natives; whereas extremely few southern forms have become naturalised in any part of Europe, though hides, wool, and other objects likely to carry seeds have been largely imported into Europe during the last two or three centuries from La Plata, and during the last thirty or forty years from Australia. Something of the same kind must have occurred on the intertropical mountains: no doubt before the Glacial period they were stocked with endemic Alpine forms; but these have almost everywhere largely yielded to the more dominant forms, generated in the larger areas and more efficient workshops of the north. In many islands the native productions are nearly equalled or even outnumbered by the naturalised; and if the natives have not been actually exterminated, their numbers have been greatly reduced, and this is the first stage towards extinction. A mountain is an island on the land; and the intertropical mountains before the Glacial period must have been completely isolated; and I believe that the productions of these islands on the land yielded to those produced within the larger areas of the north, just in the same way as the productions of real islands have everywhere lately yielded to continental forms, naturalised by man's agency.

I am far from supposing that all difficulties are removed on the view here given in regard to the range and affinities of the allied species which live in the northern and southern temperate zones and on the mountains of the intertropical regions. Very many difficulties remain to be solved. I do not pretend to indicate the exact lines and means of migration, or the reason why certain species and not others have migrated; why certain species have been modified and have given rise to new groups of forms, and others have remained unaltered. We cannot hope to explain such facts, until we can say why one species and not another becomes naturalised by man's agency in a foreign land; why one ranges twice or thrice as far, and is twice or thrice as common, as another species within their own homes.

I have said that many difficulties remain to be solved: some of the most remarkable are stated with admirable clearness by Dr. Hooker in his botanical works on the antarctic regions. These cannot be here discussed. I will only say that as far as regards the occurrence of identical species at points so enormously remote as Kerguelen Land, New Zealand, and Fuegia, I believe that towards the close of the Glacial period, icebergs, as suggested by Lyell, have been largely concerned in their dispersal. But the existence of several quite distinct species, belonging to genera exclusively confined to the south, at these and other distant points of the southern hemisphere, is, on my theory of descent with modification, a far more remarkable case of difficulty. For some of these species are so distinct, that we cannot suppose that there has been time since the commencement of the Glacial period for their migration, and for their subsequent modification to the necessary degree. The facts seem to me to indicate that peculiar and very distinct species have migrated in radiating lines from some common centre; and I am inclined to look in the southern, as in the northern hemisphere, to a former and warmer period, before the commencement of the Glacial period, when the antarctic lands, now covered with ice, supported a highly peculiar and isolated flora. I suspect that before this flora was exterminated by the Glacial epoch, a few forms were widely dispersed to various points of the southern hemisphere by occasional means of transport, and by the aid, as halting-places, of existing and now sunken islands, and perhaps at the commencement of the Glacial period, by icebergs. By these means, as I believe, the southern shores of America, Australia, New Zealand have become slightly tinted by the same peculiar forms of vegetable life.

Sir C. Lyell in a striking passage has speculated, in language almost identical with mine, on the effects of great alterations of climate on geographical distribution. I believe that the world has recently felt one of his great cycles of change; and that on this view, combined with modification through natural selection, a multitude of facts in the present distribution both of the same and of allied forms of life can be explained. The living waters may be said to have flowed during one short period from the north and from the south, and to have crossed at the equator; but to have flowed with greater force from the north so as to have freely inundated the south. As the tide leaves its drift in horizontal lines, though rising higher on the shores where the tide rises highest, so have the living waters left their living drift on our mountain-summits, in a line gently rising from the arctic lowlands to a great height under the equator. The various beings thus left stranded may be compared with savage races of man, driven up and surviving in the mountain-fastnesses of almost every land, which serve as a record, full of interest to us, of the former inhabitants of the surrounding lowlands. 
As lakes and river-systems are separated from each other by barriers of land, it might have been thought that fresh-water productions would not have ranged widely within the same country, and as the sea is apparently a still more impassable barrier, that they never would have extended to distant countries. But the case is exactly the reverse. Not only have many fresh-water species, belonging to quite different classes, an enormous range, but allied species prevail in a remarkable manner throughout the world. I well remember, when first collecting in the fresh waters of Brazil, feeling much surprise at the similarity of the fresh-water insects, shells, &c., and at the dissimilarity of the surrounding terrestrial beings, compared with those of Britain.

But this power in fresh-water productions of ranging widely, though so unexpected, can, I think, in most cases be explained by their having become fitted, in a manner highly useful to them, for short and frequent migrations from pond to pond, or from stream to stream; and liability to wide dispersal would follow from this capacity as an almost necessary consequence. We can here consider only a few cases. In regard to fish, I believe that the same species never occur in the fresh waters of distant continents. But on the same continent the species often range widely and almost capriciously; for two river-systems will have some fish in common and some different. A few facts seem to favour the possibility of their occasional transport by accidental means; like that of the live fish not rarely dropped by whirlwinds in India, and the vitality of their ova when removed from the water. But I am inclined to attribute the dispersal of fresh-water fish mainly to slight changes within the recent period in the level of the land, having caused rivers to flow into each other. Instances, also, could be given of this having occurred during floods, without any change of level. We have evidence in the loess of the Rhine of considerable changes of level in the land within a very recent geological period, and when the surface was peopled by existing land and fresh-water shells. The wide difference of the fish on opposite sides of continuous mountain-ranges, which from an early period must have parted river-systems and completely prevented their inosculation, seems to lead to this same conclusion. With respect to allied fresh-water fish occurring at very distant points of the world, no doubt there are many cases which cannot at present be explained: but some fresh-water fish belong to very ancient forms, and in such cases there will have been ample time for great geographical changes, and consequently time and means for much migration. In the second place, salt-water fish can with care be slowly accustomed to live in fresh water; and, according to Valenciennes, there is hardly a single group of fishes confined exclusively to fresh water, so that we may imagine that a marine member of a fresh-water group might travel far along the shores of the sea, and subsequently become modified and adapted to the fresh waters of a distant land.

Some species of fresh-water shells have a very wide range, and allied species, which, on my theory, are descended from a common parent and must have proceeded from a single source, prevail throughout the world. Their distribution at first perplexed me much, as their ova are not likely to be transported by birds, and they are immediately killed by sea water, as are the adults. I could not even understand how some naturalised species have rapidly spread throughout the same country. But two facts, which I have observed and no doubt many others remain to be observed throw some light on this subject. When a duck suddenly emerges from a pond covered with duck-weed, I have twice seen these little plants adhering to its back; and it has happened to me, in removing a little duck-weed from one aquarium to another, that I have quite unintentionally stocked the one with fresh-water shells from the other. But another agency is perhaps more effectual: I suspended a duck's feet, which might represent those of a bird sleeping in a natural pond, in an aquarium, where many ova of fresh-water shells were hatching; and I found that numbers of the extremely minute and just hatched shells crawled on the feet, and clung to them so firmly that when taken out of the water they could not be jarred off, though at a somewhat more advanced age they would voluntarily drop off. These just hatched molluscs, though aquatic in their nature, survived on the duck's feet, in damp air, from twelve to twenty hours; and in this length of time a duck or heron might fly at least six or seven hundred miles, and would be sure to alight on a pool or rivulet, if blown across sea to an oceanic island or to any other distant point. Sir Charles Lyell also informs me that a Dyticus has been caught with an Ancylus (a fresh-water shell like a limpet) firmly adhering to it; and a water-beetle of the same family, a Colymbetes, once flew on board the `Beagle,' when forty-five miles distant from the nearest land: how much farther it might have flown with a favouring gale no one can tell.

With respect to plants, it has long been known what enormous ranges many fresh-water and even marsh-species have, both over continents and to the most remote oceanic islands. This is strikingly shown, as remarked by Alph. de Candolle, in large groups of terrestrial plants, which have only a very few aquatic members; for these latter seem immediately to acquire, as if in consequence, a very wide range. I think favourable means of dispersal explain this fact. I have before mentioned that earth occasionally, though rarely, adheres in some quantity to the feet and beaks of birds. Wading birds, which frequent the muddy edges of ponds, if suddenly flushed, would be the most likely to have muddy feet. Birds of this order I can show are the greatest wanderers, and are occasionally found on the most remote and barren islands in the open ocean; they would not be likely to alight on the surface of the sea, so that the dirt would not be washed off their feet; when making land, they would be sure to fly to their natural fresh-water haunts. I do not believe that botanists are aware how charged the mud of ponds is with seeds: I have tried several little experiments, but will here give only the most striking case: I took in February three table-spoonfuls of mud from three different points, beneath water, on the edge of a little pond; this mud when dry weighed only 6 3/4 ounces; I kept it covered up in my study for six months, pulling up and counting each plant as it grew; the plants were of many kinds, and were altogether 537 in number; and yet the viscid mud was all contained in a breakfast cup! Considering these facts, I think it would be an inexplicable circumstance if water-birds did not transport the seeds of fresh-water plants to vast distances, and if consequently the range of these plants was not very great. The same agency may have come into play with the eggs of some of the smaller fresh-water animals.

Other and unknown agencies probably have also played a part. I have stated that fresh-water fish eat some kinds of seeds, though they reject many other kinds after having swallowed them; even small fish swallow seeds of moderate size, as of the yellow water-lily and Potamogeton. Herons and other birds, century after century, have gone on daily devouring fish; they then take flight and go to other waters, or are blown across the sea; and we have seen that seeds retain their power of germination, when rejected in pellets or in excrement, many hours afterwards. When I saw the great size of the seeds of that fine water-lily, the Nelumbium, and remembered Alph. de Candolle's remarks on this plant, I thought that its distribution must remain quite inexplicable; but Audubon states that he found the seeds of the great southern water-lily (probably, according to Dr Hooker, the Nelumbium luteum) in a heron's stomach; although I do not know the fact, yet analogy makes me believe that a heron flying to another pond and getting a hearty meal of fish, would probably reject from its stomach a pellet containing the seeds of the Nelumbium undigested; or the seeds might be dropped by the bird whilst feeding its young, in the same way as fish are known sometimes to be dropped.

In considering these several means of distribution, it should be remembered that when a pond or stream is first formed, for instance, on a rising islet, it will be unoccupied; and a single seed or egg will have a good chance of succeeding. Although there will always be a struggle for life between the individuals of the species, however few, already occupying any pond, yet as the number of kinds is small, compared with those on the land, the competition will probably be less severe between aquatic than between terrestrial species; consequently an intruder from the waters of a foreign country, would have a better chance of seizing on a place, than in the case of terrestrial colonists. We should, also, remember that some, perhaps many, fresh-water productions are low in the scale of nature, and that we have reason to believe that such low beings change or become modified less quickly than the high; and this will give longer time than the average for the migration of the same aquatic species. We should not forget the probability of many species having formerly ranged as continuously as fresh-water productions ever can range, over immense areas, and having subsequently become extinct in intermediate regions. But the wide distribution of fresh-water plants and of the lower animals, whether retaining the same identical form or in some degree modified, I believe mainly depends on the wide dispersal of their seeds and eggs by animals, more especially by fresh-water birds, which have large powers of flight, and naturally travel from one to another and often distant piece of water. Nature, like a careful gardener, thus takes her seeds from a bed of a particular nature, and drops them in another equally well fitted for them.

On the Inhabitants of Oceanic Islands

We now come to the last of the three classes of facts, which I have selected as presenting the greatest amount of difficulty, on the view that all the individuals both of the same and of allied species have descended from a single parent; and therefore have all proceeded from a common birthplace, notwithstanding that in the course of time they have come to inhabit distant points of the globe. I have already stated that I cannot honestly admit Forbes's view on continental extensions, which, if legitimately followed out, would lead to the belief that within the recent period all existing islands have been nearly or quite joined to some continent. This view would remove many difficulties, but it would not, I think, explain all the facts in regard to insular productions. In the following remarks I shall not confine myself to the mere question of dispersal; but shall consider some other facts, which bear on the truth of the two theories of independent creation and of descent with modification.

The species of all kinds which inhabit oceanic islands are few in number compared with those on equal continental areas: Alph. de Candolle admits this for plants, and Wollaston for insects. If we look to the large size and varied stations of New Zealand, extending over 780 miles of latitude, and compare its flowering plants, only 750 in number, with those on an equal area at the Cape of Good Hope or in Australia, we must, I think, admit that something quite independently of any difference in physical conditions has caused so great a difference in number. Even the uniform county of Cambridge has 847 plants, and the little island of Anglesea 764, but a few ferns and a few introduced plants are included in these numbers, and the comparison in some other respects is not quite fair. We have evidence that the barren island of Ascension aboriginally possessed under half-a-dozen flowering plants; yet many have become naturalised on it, as they have on New Zealand and on every other oceanic island which can be named. In St. Helena there is reason to believe that the naturalised plants and animals have nearly or quite exterminated many native productions. He who admits the doctrine of the creation of each separate species, will have to admit, that a sufficient number of the best adapted plants and animals have not been created on oceanic islands; for man has unintentionally stocked them from various sources far more fully and perfectly than has nature.

Although in oceanic islands the number of kinds of inhabitants is scanty, the proportion of endemic species (i.e. those found nowhere else in the world) is often extremely large. If we compare, for instance, the number of the endemic land-shells in Madeira, or of the endemic birds in the Galapagos Archipelago, with the number found on any continent, and then compare the area of the islands with that of the continent, we shall see that this is true. This fact might have been expected on my theory for, as already explained, species occasionally arriving after long intervals in a new and isolated district, and having to compete with new associates, will be eminently liable to modification, and will often produce groups of modified descendants. But it by no means follows, that, because in an island nearly all the species of one class are peculiar, those of another class, or of another section of the same class, are peculiar; and this difference seems to depend on the species which do not become modified having immigrated with facility and in a body, so that their mutual relations have not been much disturbed. Thus in the Galapagos Islands nearly every land-bird, but only two out of the eleven marine birds, are peculiar; and it is obvious that marine birds could arrive at these islands more easily than land-birds. Bermuda, on the other hand, which lies at about the same distance from North America as the Galapagos Islands do from South America, and which has a very peculiar soil, does not possess one endemic land bird; and we know from Mr. J. M. Jones's admirable account of Bermuda, that very many North American birds, during their great annual migrations, visit either periodically or occasionally this island. Madeira does not possess one peculiar bird, and many European and African birds are almost every year blown there, as I am informed by Mr. E. V. Harcourt. So that these two islands of Bermuda and Madeira have been stocked by birds, which for long ages have struggled together in their former homes, and have become mutually adapted to each other; and when settled in their new homes, each kind will have been kept by the others to their proper places and habits, and will consequently have been little liable to modification. Madeira, again, is inhabited by a wonderful number of peculiar land-shells, whereas not one species of sea-shell is confined to its shores: now, though we do not know how seashells are dispersed, yet we can see that their eggs or larvae, perhaps attached to seaweed or floating timber, or to the feet of wading-birds, might be transported far more easily than land-shells, across three or four hundred miles of open sea. The different orders of insects in Madeira apparently present analogous facts.

Oceanic islands are sometimes deficient in certain classes, and their places are apparently occupied by the other inhabitants; in the Galapagos Islands reptiles, and in New Zealand gigantic wingless birds, take the place of mammals. In the plants of the Galapagos Islands, Dr. Hooker has shown that the proportional numbers of the different orders are very different from what they are elsewhere. Such cases are generally accounted for by the physical conditions of the islands; but this explanation seems to me not a little doubtful. Facility of immigration, I believe, has been at least as important as the nature of the conditions.

Many remarkable little facts could be given with respect to the inhabitants of remote islands. For instance, in certain islands not tenanted by mammals, some of the endemic plants have beautifully hooked seeds; yet few relations are more striking than the adaptation of hooked seeds for transportal by the wool and fur of quadrupeds. This case presents no difficulty on my view, for a hooked seed might be transported to an island by some other means; and the plant then becoming slightly modified, but still retaining its hooked seeds, would form an endemic species, having as useless an appendage as any rudimentary organ, for instance, as the shrivelled wings under the soldered elytra of many insular beetles. Again, islands often possess trees or bushes belonging to orders which elsewhere include only herbaceous species; now trees, as Alph. de Candolle has shown, generally have, whatever the cause may be, confined ranges. Hence trees would be little likely to reach distant oceanic islands; and an herbaceous plant, though it would have no chance of successfully competing in stature with a fully developed tree, when established on an island and having to compete with herbaceous plants alone, might readily gain an advantage by growing taller and taller and overtopping the other plants. If so, natural selection would often tend to add to the stature of herbaceous plants when growing on an island, to whatever order they belonged, and thus convert them first into bushes and ultimately into trees.

With respect to the absence of whole orders on oceanic islands, Bory St. Vincent long ago remarked that Batrachians (frogs, toads, newts) have never been found on any of the many islands with which the great oceans are studded. I have taken pains to verify this assertion, and I have found it strictly true. I have, however, been assured that a frog exists on the mountains of the great island of New Zealand; but I suspect that this exception (if the information be correct) may be explained through glacial agency. This general absence of frogs, toads, and newts on so many oceanic islands cannot be accounted for by their physical conditions; indeed it seems that islands are peculiarly well fitted for these animals; for frogs have been introduced into Madeira, the Azores, and Mauritius, and have multiplied so as to become a nuisance. But as these animals and their spawn are known to be immediately killed by sea-water, on my view we can see that there would be great difficulty in their transportal across the sea, and therefore why they do not exist on any oceanic island. But why, on the theory of creation, they should not have been created there, it would be very difficult to explain.

Mammals offer another and similar case. I have carefully searched the oldest voyages, but have not finished my search; as yet I have not found a single instance, free from doubt, of a terrestrial mammal (excluding domesticated animals kept by the natives) inhabiting an island situated above 300 miles from a continent or great continental island; and many islands situated at a much less distance are equally barren. The Falkland Islands, which are inhabited by a wolf-like fox, come nearest to an exception; but this group cannot be considered as oceanic, as it lies on a bank connected with the mainland; moreover, icebergs formerly brought boulders to its western shores, and they may have formerly transported foxes, as so frequently now happens in the arctic regions. Yet it cannot be said that small islands will not support small mammals, for they occur in many parts of the world on very small islands, if close to a continent; and hardly an island can be named on which our smaller quadrupeds have not become naturalised and greatly multiplied. It cannot be said, on the ordinary view of creation, that there has not been time for the creation of mammals; many volcanic islands are sufficiently ancient, as shown by the stupendous degradation which they have suffered and by their tertiary strata: there has also been time for the production of endemic species belonging to other classes; and on continents it is thought that mammals appear and disappear at a quicker rate than other and lower animals. Though terrestrial mammals do not occur on oceanic islands, aërial mammals do occur on almost every island. New Zealand possesses two bats found nowhere else in the world: Norfolk Island, the Viti Archipelago, the Bonin Islands, the Caroline and Marianne Archipelagoes, and Mauritius, all possess their peculiar bats. Why, it may be asked, has the supposed creative force produced bats and no other mammals on remote islands? On my view this question can easily be answered; for no terrestrial mammal can be transported across a wide space of sea, but bats can fly across. Bats have been seen wandering by day far over the Atlantic Ocean; and two North American species either regularly or occasionally visit Bermuda, at the distance of 600 miles from the mainland. I hear from Mr. Tomes, who has specially studied this family, that many of the same species have enormous ranges, and are found on continents and on far distant islands. Hence we have only to suppose that such wandering species have been modified through natural selection in their new homes in relation to their new position, and we can understand the presence of endemic bats on islands, with the absence of all terrestrial mammals.

Besides the absence of terrestrial mammals in relation to the remoteness of islands from continents, there is also a relation, to a certain extent independent of distance, between the depth of the sea separating an island from the neighbouring mainland, and the presence in both of the same mammiferous species or of allied species in a more or less modified condition. Mr. Windsor Earl has made some striking observations on this head in regard to the great Malay Archipelago, which is traversed near Celebes by a space of deep ocean; and this space separates two widely distinct mammalian faunas. On either side the islands are situated on moderately deep submarine banks, and they are inhabited by closely allied or identical quadrupeds. No doubt some few anomalies occur in this great archipelago, and there is much difficulty in forming a judgment in some cases owing to the probable naturalisation of certain mammals through man's agency; but we shall soon have much light thrown on the natural history of this archipelago by the admirable zeal and researches of Mr Wallace. I have not as yet had time to follow up this subject in all other quarters of the world; but as far as I have gone, the relation generally holds good. We see Britain separated by a shallow channel from Europe, and the mammals are the same on both sides; we meet with analogous facts on many islands separated by similar channels from Australia. The West Indian Islands stand on a deeply submerged bank, nearly 1000 fathoms in depth, and here we find American forms, but the species and even the genera are distinct. As the amount of modification in all cases depends to a certain degree on the lapse of time, and as during changes of level it is obvious that islands separated by shallow channels are more likely to have been continuously united within a recent period to the mainland than islands separated by deeper channels, we can understand the frequent relation between the depth of the sea and the degree of affinity of the mammalian inhabitants of islands with those of a neighbouring continent, an explicable relation on the view of independent acts of creation.

All the foregoing remarks on the inhabitants of oceanic islands, namely, the scarcity of kinds -- the richness in endemic forms in particular classes or sections of classes, the absence of whole groups, as of batrachians, and of terrestrial mammals notwithstanding the presence of aërial bats, the singular proportions of certain orders of plants, herbaceous forms having been developed into trees, &c., seem to me to accord better with the view of occasional means of transport having been largely efficient in the long course of time, than with the view of all our oceanic islands having been formerly connected by continuous land with the nearest continent; for on this latter view the migration would probably have been more complete; and if modification be admitted, all the forms of life would have been more equally modified, in accordance with the paramount importance of the relation of organism to organism.

I do not deny that there are many and grave difficulties in understanding how several of the inhabitants of the more remote islands, whether still retaining the same specific form or modified since their arrival, could have reached their present homes. But the probability of many islands having existed as halting-places, of which not a wreck now remains, must not be overlooked. I will here give a single instance of one of the cases of difficulty. Almost all oceanic islands, even the most isolated and smallest, are inhabited by land-shells, generally by endemic species, but sometimes by species found elsewhere. Dr. Aug. A. Gould has given several interesting cases in regard to the land-shells of the islands of the Pacific. Now it is notorious that land-shells are very easily killed by salt; their eggs, at least such as I have tried, sink in sea-water and are killed by it. Yet there must be, on my view, some unknown, but highly efficient means for their transportal. Would the just-hatched young occasionally crawl on and adhere to the feet of birds roosting on the ground, and thus get transported? It occurred to me that land-shells, when hybernating and having a membranous diaphragm over the mouth of the shell, might be floated in chinks of drifted timber across moderately wide arms of the sea. And I found that several species did in this state withstand uninjured an immersion in sea-water during seven days: one of these shells was the Helix pomatia, and after it had again hybernated I put it in sea-water for twenty days, and it perfectly recovered. As this species has a thick calcareous operculum, I removed it, and when it had formed a new membranous one, I immersed it for fourteen days in sea-water, and it recovered and crawled away: but more experiments are wanted on this head.

The most striking and important fact for us in regard to the inhabitants of islands, is their affinity to those of the nearest mainland, without being actually the same species. Numerous instances could be given of this fact. I will give only one, that of the Galapagos Archipelago, situated under the equator, between 500 and 600 miles from the shores of South America. Here almost every product of the land and water bears the unmistakeable stamp of the American continent. There are twenty-six land birds, and twenty-five of those are ranked by Mr Gould as distinct species, supposed to have been created here; yet the close affinity of most of these birds to American species in every character, in their habits, gestures, and tones of voice, was manifest. So it is with the other animals, and with nearly all the plants, as shown by Dr. Hooker in his admirable memoir on the Flora of this archipelago. The naturalist, looking at the inhabitants of these volcanic islands in the Pacific, distant several hundred miles from the continent, yet feels that he is standing on American land. Why should this be so? why should the species which are supposed to have been created in the Galapagos Archipelago, and nowhere else, bear so plain a stamp of affinity to those created in America? There is nothing in the conditions of life, in the geological nature of the islands, in their height or climate, or in the proportions in which the several classes are associated together, which resembles closely the conditions of the South American coast: in fact there is a considerable dissimilarity in all these respects. On the other hand, there is a considerable degree of resemblance in the volcanic nature of the soil, in climate, height, and size of the islands, between the Galapagos and Cape de Verde Archipelagos: but what an entire and absolute difference in their inhabitants! The inhabitants of the Cape de Verde Islands are related to those of Africa, like those of the Galapagos to America. I believe this grand fact can receive no sort of explanation on the ordinary view of independent creation; whereas on the view here maintained, it is obvious that the Galapagos Islands would be likely to receive colonists, whether by occasional means of transport or by formerly continuous land, from America; and the Cape de Verde Islands from Africa; and that such colonists would be liable to modifications; the principle of inheritance still betraying their original birthplace.

Many analogous facts could be given: indeed it is an almost universal rule that the endemic productions of islands are related to those of the nearest continent, or of other near islands. The exceptions are few, and most of them can be explained. Thus the plants of Kerguelen Land, though standing nearer to Africa than to America, are related, and that very closely, as we know from Dr. Hooker's account, to those of America: but on the view that this island has been mainly stocked by seeds brought with earth and stones on icebergs, drifted by the prevailing currents, this anomaly disappears. New Zealand in its endemic plants is much more closely related to Australia, the nearest mainland, than to any other region: and this is what might have been expected; but it is also plainly related to South America, which, although the next nearest continent, is so enormously remote, that the fact becomes an anomaly. But this difficulty almost disappears on the view that both New Zealand, South America, and other southern lands were long ago partially stocked from a nearly intermediate though distant point, namely from the antarctic islands, when they were clothed with vegetation, before the commencement of the Glacial period. The affinity, which, though feeble, I am assured by Dr. Hooker is real, between the flora of the south-western corner of Australia and of the Cape of Good Hope, is a far more remarkable case, and is at present inexplicable: but this affinity is confined to the plants, and will, I do not doubt, be some day explained.

The law which causes the inhabitants of an archipelago, though specifically distinct, to be closely allied to those of the nearest continent, we sometimes see displayed on a small scale, yet in a most interesting manner, within the limits of the same archipelago. Thus the several islands of the Galapagos Archipelago are tenanted, as I have elsewhere shown, in a quite marvellous manner, by very closely related species; so that the inhabitants of each separate island, though mostly distinct, are related in an incomparably closer degree to each other than to the inhabitants of any other part of the world. And this is just what might have been expected on my view, for the islands are situated so near each other that they would almost certainly receive immigrants from the same original source, or from each other. But this dissimilarity between the endemic inhabitants of the islands may be used as an argument against my views; for it may be asked, how has it happened in the several islands situated within sight of each other, having the same geological nature, the same height, climate, &c., that many of the immigrants should have been differently modified, though only in a small degree. This long appeared to me a great difficulty: but it arises in chief part from the deeply-seated error of considering the physical conditions of a country as the most important for its inhabitants; whereas it cannot, I think, be disputed that the nature of the other inhabitants, with which each has to compete, is at least as important, and generally a far more important element of success. Now if we look to those inhabitants of the Galapagos Archipelago which are found in other parts of the world (having on one side for the moment the endemic species, which cannot be here fairly included, as we are considering how they have come to be modified since their arrival), we find a considerable amount of difference in the several islands. This difference might indeed have been expected on the view of the islands having been stocked by occasional means of transport a seed, for instance, of one plant having been brought to one island, and that of another plant to another island. Hence when in former times an immigrant settled on any one or more of the islands, or when it subsequently spread from one island to another, it would undoubtedly be exposed to different conditions of life in the different islands, for it would have to compete with different sets of organisms: a plant, for instance, would find the best-fitted ground more perfectly occupied by distinct plants in one island than in another, and it would be exposed to the attacks of somewhat different enemies. If then it varied, natural selection would probably favour different varieties in the different islands. Some species, however, might spread and yet retain the same character throughout the group, just as we see on continents some species' spreading widely and remaining the same.

The really surprising fact in this case of the Galapagos Archipelago, and in a lesser degree in some analogous instances, is that the new species formed in the separate islands have not quickly spread to the other islands. But the islands, though in sight of each other, are separated by deep arms of the sea, in most cases wider than the British Channel, and there is no reason to suppose that they have at any former period been continuously united. The currents of the sea are rapid and sweep across the archipelago, and gales of wind are extraordinarily rare; so that the islands are far more effectually separated from each other than they appear to be on a map. Nevertheless a good many species, both those found in other parts of the world and those confined to the archipelago, are common to the several islands, and we may infer from certain facts that these have probably spread from some one island to the others. But we often take, I think, an erroneous view of the probability of closely allied species invading each other's territory, when put into free intercommunication. Undoubtedly if one species has any advantage whatever over another, it will in a very brief time wholly or in part supplant it; but if both are equally well fitted for their own places in nature, both probably will hold their own places and keep separate for almost any length of time. Being familiar with the fact that many species, naturalised through man's agency, have spread with astonishing rapidity over new countries, we are apt to infer that most species would thus spread; but we should remember that the forms which become naturalised in new countries are not generally closely allied to the aboriginal inhabitants, but are very distinct species, belonging in a large proportion of cases, as shown by Alph. de Candolle, to distinct genera. In the Galapagos Archipelago, many even of the birds, though so well adapted for flying from island to island, are distinct on each; thus there are three closely-allied species of mocking-thrush, each confined to its own island. Now let us suppose the mocking-thrush of Chatham Island to be blown to Charles Island, which has its own mocking-thrush: why should it succeed in establishing itself there? We may safely infer that Charles Island is well stocked with its own species, for annually more eggs are laid there than can possibly be reared; and we may infer that the mocking-thrush peculiar to Charles Island is at least as well fitted for its home as is the species peculiar to Chatham Island. Sir C. Lyell and Mr. Wollaston have communicated to me a remarkable fact bearing on this subject; namely, that Madeira and the adjoining islet of Porto Santo possess many distinct but representative land-shells, some of which live in crevices of stone; and although large quantities of stone are annually transported from Porto Santo to Madeira, yet this latter island has not become colonised by the Porto Santo species: nevertheless both islands have been colonised by some European land-shells, which no doubt had some advantage over the indigenous species. From these considerations I think we need not greatly marvel at the endemic and representative species, which inhabit the several islands of the Galapagos Archipelago, not having universally spread from island to island. In many other instances, as in the several districts of the same continent, pre-occupation has probably played an important part in checking the commingling of species under the same conditions of life. Thus, the south-east and south-west corners of Australia have nearly the same physical conditions, and are united by continuous land, yet they are inhabited by a vast number of distinct mammals, birds, and plants.

The principle which determines the general character of the fauna and flora of oceanic islands, namely, that the inhabitants, when not identically the same, yet are plainly related to the inhabitants of that region whence colonists could most readily have been derived, the colonists having been subsequently modified and better fitted to their new homes, is of the widest application throughout nature. We see this on every mountain, in every lake and marsh. For Alpine species, excepting in so far as the same forms, chiefly of plants, have spread widely throughout the world during the recent Glacial epoch, are related to those of the surrounding lowlands; thus we have in South America, Alpine humming-birds, Alpine rodents, Alpine plants, &c., all of strictly American forms, and it is obvious that a mountain, as it became slowly upheaved, would naturally be colonised from the surrounding lowlands. So it is with the inhabitants of lakes and marshes, excepting in so far as great facility of transport has given the same general forms to the whole world. We see this same principle in the blind animals inhabiting the caves of America and of Europe. Other analogous facts could be given. And it will, I believe, be universally found to be true, that wherever in two regions, let them be ever so distant, many closely allied or representative species occur, there will likewise be found some identical species, showing, in accordance with the foregoing view, that at some former period there has been intercommunication or migration between the two regions. And wherever many closely-allied species occur, there will be found many forms which some naturalists rank as distinct species, and some as varieties; these doubtful forms showing us the steps in the process of modification.

This relation between the power and extent of migration of a species, either at the present time or at some former period under different physical conditions, and the existence at remote points of the world of other species allied to it, is shown in another and more general way. Mr. Gould remarked to me long ago, that in those genera of birds which range over the world, many of the species have very wide ranges. I can hardly doubt that this rule is generally true, though it would be difficult to prove it. Amongst mammals, we see it strikingly displayed in Bats, and in a lesser degree in the Felidae and Canidae. We see it, if we compare the distribution of butterflies and beetles. So it is with most fresh-water productions, in which so many genera range over the world, and many individual species have enormous ranges. It is not meant that in world-ranging genera all the species have a wide range, or even that they have on an average a wide range; but only that some of the species range very widely; for the facility with which widely-ranging species vary and give rise to new forms will largely determine their average range. For instance, two varieties of the same species inhabit America and Europe, and the species thus has an immense range; but, if the variation had been a little greater, the two varieties would have been ranked as distinct species, and the common range would have been greatly reduced. Still less is it meant, that a species which apparently has the capacity of crossing barriers and ranging widely, as in the case of certain powerfully-winged birds, will necessarily range widely; for we should never forget that to range widely implies not only the power of crossing barriers, but the more important power of being victorious in distant lands in the struggle for life with foreign associates. But on the view of all the species of a genus having descended from a single parent, though now distributed to the most remote points of the world, we ought to find, and I believe as a general rule we do find, that some at least of the species range very widely; for it is necessary that the unmodified parent should range widely, undergoing modification during its diffusion, and should place itself under diverse conditions favourable for the conversion of its offspring, firstly into new varieties and ultimately into new species.

In considering the wide distribution of certain genera, we should bear in mind that some are extremely ancient, and must have branched off from a common parent at a remote epoch; so that in such cases there will have been ample time for great climatal and geographical changes and for accidents of transport; and consequently for the migration of some of the species into all quarters of the world, where they may have become slightly modified in relation to their new conditions. There is, also, some reason to believe from geological evidence that organisms low in the scale within each great class, generally change at a slower rate than the higher forms; and consequently the lower forms will have had a better chance of ranging widely and of still retaining the same specific character. This fact, together with the seeds and eggs of many low forms being very minute and better fitted for distant transportation, probably accounts for a law which has long been observed, and which has lately been admirably discussed by Alph. de Candolle in regard to plants, namely, that the lower any group of organisms is, the more widely it is apt to range.

The relations just discussed, namely, low and slowly-changing organisms ranging more widely than the high, some of the species of widely-ranging genera themselves ranging widely, such facts, as alpine, lacustrine, and marsh productions being related (with the exceptions before specified) to those on the surrounding low lands and dry lands, though these stations are so different the very close relation of the distinct species which inhabit the islets of the same archipelago, and especially the striking relation of the inhabitants of each whole archipelago or island to those of the nearest mainland, are, I think, utterly inexplicable on the ordinary view of the independent creation of each species, but are explicable on the view of colonisation from the nearest and readiest source, together with the subsequent modification and better adaptation of the colonists to their new homes.
Summary of last and present Chapters

In these chapters I have endeavoured to show, that if we make due allowance for our ignorance of the full effects of all the changes of climate and of the level of the land, which have certainly occurred within the recent period, and of other similar changes which may have occurred within the same period; if we remember how profoundly ignorant we are with respect to the many and curious means of occasional transport, a subject which has hardly ever been properly experimentised on; if we bear in mind how often a species may have ranged continuously over a wide area, and then have become extinct in the intermediate tracts, I think the difficulties in believing that all the individuals of the same species, wherever located, have descended from the same parents, are not insuperable. And we are led to this conclusion, which has been arrived at by many naturalists under the designation of single centres of creation, by some general considerations, more especially from the importance of barriers and from the analogical distribution of sub-genera, genera, and families.

With respect to the distinct species of the same genus, which on my theory must have spread from one parent-source; if we make the same allowances as before for our ignorance, and remember that some forms of life change most slowly, enormous periods of time being thus granted for their migration, I do not think that the difficulties are insuperable; though they often are in this case, and in that of the individuals of the same species, extremely grave.

As exemplifying the effects of climatal changes on distribution, I have attempted to show how important has been the influence of the modern Glacial period, which I am fully convinced simultaneously affected the whole world, or at least great meridional belts. As showing how diversified are the means of occasional transport, I have discussed at some little length the means of dispersal of fresh-water productions.

If the difficulties be not insuperable in admitting that in the long course of time the individuals of the same species, and likewise of allied species, have proceeded from some one source; then I think all the grand leading facts of geographical distribution are explicable on the theory of migration (generally of the more dominant forms of life), together with subsequent modification and the multiplication of new forms. We can thus understand the high importance of barriers, whether of land or water, which separate our several zoological and botanical provinces. We can thus understand the localisation of sub-genera, genera, and families; and how it is that under different latitudes, for instance in South America, the inhabitants of the plains and mountains, of the forests, marshes, and deserts, are in so mysterious a manner linked together by affinity, and are likewise linked to the extinct beings which formerly inhabited the same continent. Bearing in mind that the mutual relations of organism to organism are of the highest importance, we can see why two areas having nearly the same physical conditions should often be inhabited by very different forms of life; for according to the length of time which has elapsed since new inhabitants entered one region; according to the nature of the communication which allowed certain forms and not others to enter, either in greater or lesser numbers; according or not, as those which entered happened to come in more or less direct competition with each other and with the aborigines; and according as the immigrants were capable of varying more or less rapidly, there would ensue in different regions, independently of their physical conditions, infinitely diversified conditions of life, there would be an almost endless amount of organic action and reaction, and we should find, as we do find, some groups of beings greatly, and some only slightly modified, some developed in great force, some existing in scanty numbers in the different great geographical provinces of the world.

On these same principles, we can understand, as I have endeavoured to show, why oceanic islands should have few inhabitants, but of these a great number should be endemic or peculiar; and why, in relation to the means of migration, one group of beings, even within the same class, should have all its species endemic, and another group should have all its species common to other quarters of the world. We can see why whole groups of organisms, as batrachians and terrestrial mammals, should be absent from oceanic islands, whilst the most isolated islands possess their own peculiar species of aërial mammals or bats. We can see why there should be some relation between the presence of mammals, in a more or less modified condition, and the depth of the sea between an island and the mainland. We can clearly see why all the inhabitants of an archipelago, though specifically distinct on the several islets, should be closely related to each other, and likewise be related, but less closely, to those of the nearest continent or other source whence immigrants were probably derived. We can see why in two areas, however distant from each other, there should be a correlation, in the presence of identical species, of varieties, of doubtful species, and of distinct but representative species.

As the late Edward Forbes often insisted, there is a striking parallelism in the laws of life throughout time and space: the laws governing the succession of forms in past times being nearly the same with those governing at the present time the differences in different areas. We see this in many facts. The endurance of each species and group of species is continuous in time; for the exceptions to the rule are so few, that they may fairly be attributed to our not having as yet discovered in an intermediate deposit the forms which are therein absent, but which occur above and below: so in space, it certainly is the general rule that the area inhabited by a single species, or by a group of species, is continuous; and the exceptions, which are not rare, may, as I have attempted to show, be accounted for by migration at some former period under different conditions or by occasional means of transport, and by the species having become extinct in the intermediate tracts. Both in time and space, species and groups of species have their points of maximum development. Groups of species, belonging either to a certain period of time, or to a certain area, are often characterised by trifling characters in common, as of sculpture or colour. In looking to the long succession of ages, as in now looking to distant provinces throughout the world, we find that some organisms differ little, whilst others belonging to a different class, or to a different order, or even only to a different family of the same order, differ greatly. In both time and space the lower members of each class generally change less than the higher; but there are in both cases marked exceptions to the rule. On my theory these several relations throughout time and space are intelligible; for whether we look to the forms of life which have changed during successive ages within the same quarter of the world, or to those which have changed after having migrated into distant quarters, in both cases the forms within each class have been connected by the same bond of ordinary generation; and the more nearly any two forms are related in blood, the nearer they will generally stand to each other in time and space; in both cases the laws of variation have been the same, and modifications have been accumulated by the same power of natural selection. 
From the first dawn of life, all organic beings are found to resemble each other in descending degrees, so that they can be classed in groups under groups. This classification is evidently not arbitrary like the grouping of the stars in constellations. The existence of groups would have been of simple signification, if one group had been exclusively fitted to inhabit the land, and another the water; one to feed on flesh, another on vegetable matter, and so on; but the case is widely different in nature; for it is notorious how commonly members of even the same subgroup have different habits. In our second and fourth chapters, on Variation and on Natural Selection, I have attempted to show that it is the widely ranging, the much diffused and common, that is the dominant species belonging to the larger genera, which vary most. The varieties, or incipient species, thus produced ultimately become converted, as I believe, into new and distinct species; and these, on the principle of inheritance, tend to produce other new and dominant species. Consequently the groups which are now large, and which generally include many dominant species, tend to go on increasing indefinitely in size. I further attempted to show that from the varying descendants of each species trying to occupy as many and as different places as possible in the economy of nature, there is a constant tendency in their characters to diverge. This conclusion was supported by looking at the great diversity of the forms of life which, in any small area, come into the closest competition, and by looking to certain facts in naturalisation.

I attempted also to show that there is a constant tendency in the forms which are increasing in number and diverging in character, to supplant and exterminate the less divergent, the less improved, and preceding forms. I request the reader to turn to the diagram illustrating the action, as formerly explained, of these several principles; and he will see that the inevitable result is that the modified descendants proceeding from one progenitor become broken up into groups subordinate to groups. In the diagram each letter on the uppermost line may represent a genus including several species; and all the genera on this line form together one class, for all have descended from one ancient but unseen parent, and, consequently, have inherited something in common. But the three genera on the left hand have, on this same principle, much in common, and form a sub-family, distinct from that including the next two genera on the right hand, which diverged from a common parent at the fifth stage of descent. These five genera have also much, though less, in common; and they form a family distinct from that including the three genera still further to the right hand, which diverged at a still earlier period. And all these genera, descended from (A), form an order distinct from the genera descended from (I). So that we here have many species descended from a single progenitor grouped into genera; and the genera are included in, or subordinate to, sub-families, families, and orders, all united into one class. Thus, the grand fact in natural history of the subordination of group under group, which, from its familiarity, does not always sufficiently strike us, is in my judgement fully explained.

Naturalists try to arrange the species, genera, and families in each class, on what is called the Natural System. But what is meant by this system? Some authors look at it merely as a scheme for arranging together those living objects which are most alike, and for separating those which are most unlike; or as an artificial means for enunciating, as briefly as possible, general propositions, that is, by one sentence to give the characters common, for instance, to all mammals, by another those common to all carnivora, by another those common to the dog-genus, and then by adding a single sentence, a full description is given of each kind of dog. The ingenuity and utility of this system are indisputable. But many naturalists think that something more is meant by the Natural System; they believe that it reveals the plan of the Creator; but unless it be specified whether order in time or space, or what else is meant by the plan of the Creator, it seems to me that nothing is thus added to our knowledge. Such expressions as that famous one of Linnaeus, and which we often meet with in a more or less concealed form, that the characters do not make the genus, but that the genus gives the characters, seem to imply that something more is included in our classification, than mere resemblance. I believe that something more is included; and that propinquity of descent, the only known cause of the similarity of organic beings, is the bond, hidden as it is by various degrees of modification, which is partially revealed to us by our classifications.

Let us now consider the rules followed in classification, and the difficulties which are encountered on the view that classification either gives some unknown plan of creation, or is simply a scheme for enunciating general propositions and of placing together the forms most like each other. It might have been thought (and was in ancient times thought) that those parts of the structure which determined the habits of life, and the general place of each being in the economy of nature, would be of very high importance in classification. Nothing can be more false. No one regards the external similarity of a mouse to a shrew, of a dugong to a whale, of a whale to a fish, as of any importance. These resemblances, though so intimately connected with the whole life of the being, are ranked as merely `adaptive or analogical characters;' but to the consideration of these resemblances we shall have to recur. It may even be given as a general rule, that the less any part of the organisation is concerned with special habits, the more important it becomes for classification. As an instance: Owen, in speaking of the dugong, says, `The generative organs being those which are most remotely related to the habits and food of an animal, I have always regarded as affording very clear indications of its true affinities. We are least likely in the modifications of these organs to mistake a merely adaptive for an essential character.' So with plants, how remarkable it is that the organs of vegetation, on which their whole life depends, are of little signification, excepting in the first main divisions; whereas the organs of reproduction, with their product the seed, are of paramount importance!

We must not, therefore, in classifying, trust to resemblances in parts of the organisation, however important they may be for the welfare of the being in relation to the outer world. Perhaps from this cause it has partly arisen, that almost all naturalists lay the greatest stress on resemblances in organs of high vital or physiological importance. No doubt this view of the classificatory importance of organs which are important is generally, but by no means always, true. But their importance for classification, I believe, depends on their greater constancy throughout large groups of species; and this constancy depends on such organs having generally been subjected to less change in the adaptation of the species to their conditions of life. That the mere physiological importance of an organ does not determine the classificatory value, is almost shown by the one fact, that in allied groups, in which the same organ, as we have every reason to suppose, has nearly the same physiological value, its classificatory value is widely different. No naturalist can have worked at any group without being struck with this fact; and it has been most fully acknowledged in the writings of almost every author. It will suffice to quote the highest authority, Robert Brown, who in speaking of certain organs in the Proteaceae, says their generic importance, `like that of all their parts, not only in this but, as I apprehend, in every natural family, is very unequal, and in some cases seems to be entirely lost.' Again in another work he says, the genera of the Connaraceae `differ in having one or more ovaria, in the existence or absence of albumen, in the imbricate or valvular aestivation. Any one of these characters singly is frequently of more than generic importance, though here even when all taken together they appear insufficient to separate Cnestis from Connarus.' To give an example amongst insects, in one great division of the Hymenoptera, the antennae, as Westwood has remarked, are most constant in structure; in another division they differ much, and the differences are of quite subordinate value in classification; yet no one probably will say that the antennae in these two divisions of the same order are of unequal physiological importance. Any number of instances could be given of the varying importance for classification of the same important organ within the same group of beings.

Again, no one will say that rudimentary or atrophied organs are of high physiological or vital importance; yet, undoubtedly, organs in this condition are often of high value in classification. No one will dispute that the rudimentary teeth in the upper jaws of young ruminants, and certain rudimentary bones of the leg, are highly serviceable in exhibiting the close affinity between Ruminants and Pachyderms. Robert Brown has strongly insisted on the fact that the rudimentary florets are of the highest importance in the classification of the Grasses.

Numerous instances could be given of characters derived from parts which must be considered of very trifling physiological importance, but which are universally admitted as highly serviceable in the definition of whole groups. For instance, whether or not there is an open passage from the nostrils to the mouth, the only character, according to Owen, which absolutely distinguishes fishes and reptiles the inflection of the angle of the jaws in Marsupials -- the manner in which the wings of insects are folded mere colour in certain Algae mere pubescence on parts of the flower in grasses the nature of the dermal covering, as hair or feathers, in the Vertebrata. If the Ornithorhynchus had been covered with feathers instead of hair, this external and trifling character would, I think, have been considered by naturalists as important an aid in determining the degree of affinity of this strange creature to birds and reptiles, as an approach in structure in any one internal and important organ.

The importance, for classification, of trifling characters, mainly depends on their being correlated with several other characters of more or less importance. The value indeed of an aggregate of characters is very evident in natural history. Hence, as has often been remarked, a species may depart from its allies in several characters, both of high physiological importance and of almost universal prevalence, and yet leave us in no doubt where it should be ranked. Hence, also, it has been found, that a classification founded on any single character, however important that may be, has always failed; for no part of the organisation is universally constant. The importance of an aggregate of characters, even when none are important, alone explains, I think, that saying of Linnaeus, that the characters do not give the genus, but the genus gives the characters; for this saying seems founded on an appreciation of many trifling points of resemblance, too slight to be defined. Certain plants, belonging to the Malpighiaceae, bear perfect and degraded flowers; in the latter, as A. de Jussieu has remarked, `the greater number of the characters proper to the species, to the genus, to the family, to the class, disappear, and thus laugh at our classification.' But when Aspicarpa produced in France, during several years, only degraded flowers, departing so wonderfully in a number of the most important points of structure from the proper type of the order, yet M. Richard sagaciously saw, as Jussieu observes, that this genus should still be retained amongst the Malpighiaceae. This case seems to me well to illustrate the spirit with which our classifications are sometimes necessarily founded.

Practically when naturalists are at work, they do not trouble themselves about the physiological value of the characters which they use in defining a group, or in allocating any particular species. If they find a character nearly uniform, and common to a great number of forms, and not common to others, they use it as one of high value; if common to some lesser number, they use it as of subordinate value. This principle has been broadly confessed by some naturalists to be the true one; and by none more clearly than by that excellent botanist, Aug. St. Hilaire. If certain characters are always found correlated with others, though no apparent bond of connexion can be discovered between them, especial value is set on them. As in most groups of animals, important organs, such as those for propelling the blood, or for aërating it, or those for propagating the race, are found nearly uniform, they are considered as highly serviceable in classification; but in some groups of animals all these, the most important vital organs, are found to offer characters of quite subordinate value.

We can see why characters derived from the embryo should be of equal importance with those derived from the adult, for our classifications of course include all ages of each species. But it is by no means obvious, on the ordinary view, why the structure of the embryo should be more important for this purpose than that of the adult, which alone plays its full part in the economy of nature. Yet it has been strongly urged by those great naturalists, Milne Edwards and Agassiz, that embryonic characters are the most important of any in the classification of animals; and this doctrine has very generally been admitted as true. The same fact holds good with flowering plants, of which the two main divisions have been founded on characters derived from the embryo, on the number and position of the embryonic leaves or cotyledons, and on the mode of development of the plumule and radicle. In our discussion on embryology, we shall see why such characters are so valuable, on the view of classification tacitly including the idea of descent.

Our classifications are often plainly influenced by chains of affinities. Nothing can be easier than to define a number of characters common to all birds; but in the case of crustaceans, such definition has hitherto been found impossible. There are crustaceans at the opposite ends of the series, which have hardly a character in common; yet the species at both ends, from being plainly allied to others, and these to others, and so onwards, can be recognised as unequivocally belonging to this, and to no other class of the Articulata.

Geographical distribution has often been used, though perhaps not quite logically, in classification, more especially in very large groups of closely allied forms. Temminck insists on the utility or even necessity of this practice in certain groups of birds; and it has been followed by several entomologists and botanists.

Finally, with respect to the comparative value of the various groups of species, such as orders, sub-orders, families, sub-families, and genera, they seem to be, at least at present, almost arbitrary. Several of the best botanists, such as Mr Bentham and others, have strongly insisted on their arbitrary value. Instances could be given amongst plants and insects, of a group of forms, first ranked by practised naturalists as only a genus, and then raised to the rank of a sub-family or family; and this has been done, not because further research has detected important structural differences, at first overlooked, but because numerous allied species, with slightly different grades of difference, have been subsequently discovered.

All the foregoing rules and aids and difficulties in classification are explained, if I do not greatly deceive myself, on the view that the natural system is founded on descent with modification; that the characters which naturalists consider as showing true affinity between any two or more species, are those which have been inherited from a common parent, and, in so far, all true classification is genealogical; that community of descent is the hidden bond which naturalists have been unconsciously seeking, and not some unknown plan of creation, or the enunciation of general propositions, and the mere putting together and separating objects more or less alike.

But I must explain my meaning more fully. I believe that the arrangement of the groups within each class, in due subordination and relation to the other groups, must be strictly genealogical in order to be natural; but that the amount of difference in the several branches or groups, though allied in the same degree in blood to their common progenitor, may differ greatly, being due to the different degrees of modification which they have undergone; and this is expressed by the forms being ranked under different genera, families, sections, or orders. The reader will best understand what is meant, if he will take the trouble of referring to the diagram in the fourth chapter. We will suppose the letters A to L to represent allied genera, which lived during the Silurian epoch, and these have descended from a species which existed at an unknown anterior period. Species of three of these genera (A, F, and I) have transmitted modified descendants to the present day, represented by the fifteen genera (a14 to z14) on the uppermost horizontal line. Now all these modified descendants from a single species, are represented as related in blood or descent to the same degree; they may metaphorically be called cousins to the same millionth degree; yet they differ widely and in different degrees from each other. The forms descended from A, now broken up into two or three families, constitute a distinct order from those descended from I, also broken up into two families. Nor can the existing species, descended from A, be ranked in the same genus with the parent A; or those from I, with the parent I. But the existing genus F14 may be supposed to have been but slightly modified; and it will then rank with the parent-genus F; just as some few still living organic beings belong to Silurian genera. So that the amount or value of the differences between organic beings all related to each other in the same degree in blood, has come to be widely different. Nevertheless their genealogical arrangement remains strictly true, not only at the present time, but at each successive period of descent. All the modified descendants from A will have inherited something in common from their common parent, as will all the descendants from I; so will it be with each subordinate branch of descendants, at each successive period. If, however, we choose to suppose that any of the descendants of A or of I have been so much modified as to have more or less completely lost traces of their parentage, in this case, their places in a natural classification will have been more or less completely lost, as sometimes seems to have occurred with existing organisms. All the descendants of the genus F, along its whole line of descent, are supposed to have been but little modified, and they yet form a single genus. But this genus, though much isolated, will still occupy its proper intermediate position; for F originally was intermediate in character between A and I, and the several genera descended from these two genera will have inherited to a certain extent their characters. This natural arrangement is shown, as far as is possible on paper, in the diagram, but in much too simple a manner. If a branching diagram had not been used, and only the names of the groups had been written in a linear series, it would have been still less possible to have given a natural arrangement; and it is notoriously not possible to represent in a series, on a flat surface, the affinities which we discover in nature amongst the beings of the same group. Thus, on the view which I hold, the natural system is genealogical in its arrangement, like a pedigree; but the degrees of modification which the different groups have undergone, have to be expressed by ranking them under different so-called genera, sub-families, families, sections, orders, and classes.

It may be worth while to illustrate this view of classification, by taking the case of languages. If we possessed a perfect pedigree of mankind, a genealogical arrangement of the races of man would afford the best classification of the various languages now spoken throughout the world; and if all extinct languages, and all intermediate and slowly changing dialects, had to be included, such an arrangement would, I think, be the only possible one. Yet it might be that some very ancient language had altered little, and had given rise to few new languages, whilst others (owing to the spreading and subsequent isolation and states of civilisation of the several races, descended from a common race) had altered much, and had given rise to many new languages and dialects. The various degrees of difference in the languages from the same stock, would have to be expressed by groups subordinate to groups; but the proper or even only possible arrangement would still be genealogical; and this would be strictly natural, as it would connect together all languages, extinct and modern, by the closest affinities, and would give the filiation and origin of each tongue.

In confirmation of this view, let us glance at the classification of varieties, which are believed or known to have descended from one species. These are grouped under species, with sub-varieties under varieties; and with our domestic productions, several other grades of difference are requisite, as we have seen with pigeons. The origin of the existence of groups subordinate to groups, is the same with varieties as with species, namely, closeness of descent with various degrees of modification. Nearly the same rules are followed in classifying varieties, as with species. Authors have insisted on the necessity of classing varieties on a natural instead of an artificial system; we are cautioned, for instance, not to class two varieties of the pine-apple together, merely because their fruit, though the most important part, happens to be nearly identical; no one puts the swedish and common turnips together, though the esculent and thickened stems are so similar. Whatever part is found to be most constant, is used in classing varieties: thus the great agriculturist Marshall says the horns are very useful for this purpose with cattle, because they are less variable than the shape or colour of the body, &c.; whereas with sheep the horns are much less serviceable, because less constant. In classing varieties, I apprehend if we had a real pedigree, a genealogical classification would be universally preferred; and it has been attempted by some authors. For we might feel sure, whether there had been more or less modification, the principle of inheritance would keep the forms together which were allied in the greatest number of points. In tumbler pigeons, though some sub-varieties differ from the others in the important character of having a longer beak, yet all are kept together from having the common habit of tumbling; but the short-faced breed has nearly or quite lost this habit; nevertheless, without any reasoning or thinking on the subject, these tumblers are kept in the same group, because allied in blood and alike in some other respects. If it could be proved that the Hottentot had descended from the Negro, I think he would be classed under the Negro group, however much he might differ in colour and other important characters from negroes.

With species in a state of nature, every naturalist has in fact brought descent into his classification; for he includes in his lowest grade, or that of a species, the two sexes; and how enormously these sometimes differ in the most important characters, is known to every naturalist: scarcely a single fact can be predicated in common of the males and hermaphrodites of certain cirripedes, when adult, and yet no one dreams of separating them. The naturalist includes as one species the several larval stages of the same individual, however much they may differ from each other and from the adult; as he likewise includes the so-called alternate generations of Steenstrup, which can only in a technical sense be considered as the same individual. He includes monsters; he includes varieties, not solely because they closely resemble the parent-form, but because they are descended from it. He who believes that the cowslip is descended from the primrose, or conversely, ranks them together as a single species, and gives a single definition. As soon as three Orchidean forms (Monochanthus, Myanthus, and Catasetum), which had previously been ranked as three distinct genera, were known to be sometimes produced on the same spike, they were immediately included as a single species. But it may be asked, what ought we to do, if it could be proved that one species of kangaroo had been produced, by a long course of modification, from a bear? Ought we to rank this one species with bears, and what should we do with the other species? The supposition is of course preposterous; and I might answer by the argumentum ad hominem, and ask what should be done if a perfect kangaroo were seen to come out of the womb of a bear? According to all analogy, it would be ranked with bears; but then assuredly all the other species of the kangaroo family would have to be classed under the bear genus. The whole case is preposterous; for where there has been close descent in common, there will certainly be close resemblance or affinity.

As descent has universally been used in classing together the individuals of the same species, though the males and females and larvae are sometimes extremely different; and as it has been used in classing varieties which have undergone a certain, and sometimes a considerable amount of modification, may not this same element of descent have been unconsciously used in grouping species under genera, and genera under higher groups, though in these cases the modification has been greater in degree, and has taken a longer time to complete? I believe it has thus been unconsciously used; and only thus can I understand the several rules and guides which have been followed by our best systematists. We have no written pedigrees; we have to make out community of descent by resemblances of any kind. Therefore we choose those characters which, as far as we can judge, are the least likely to have been modified in relation to the conditions of life to which each species has been recently exposed. Rudimentary structures on this view are as good as, or even sometimes better than, other parts of the organisation. We care not how trifling a character may be let it be the mere inflection of the angle of the jaw, the manner in which an insect's wing is folded, whether the skin be covered by hair or feathers if it prevail throughout many and different species, especially those having very different habits of life, it assumes high value; for we can account for its presence in so many forms with such different habits, only by its inheritance from a common parent. We may err in this respect in regard to single points of structure, but when several characters, let them be ever so trifling, occur together throughout a large group of beings having different habits, we may feel almost sure, on the theory of descent, that these characters have been inherited from a common ancestor. And we know that such correlated or aggregated characters have especial value in classification.

We can understand why a species or a group of species may depart, in several of its most important characteristics, from its allies, and yet be safely classed with them. This may be safely done, and is often done, as long as a sufficient number of characters, let them be ever so unimportant, betrays the hidden bond of community of descent. Let two forms have not a single character in common, yet if these extreme forms are connected together by a chain of intermediate groups, we may at once infer their community of descent, and we put them all into the same class. As we find organs of high physiological importance those which serve to preserve life under the most diverse conditions of existence are generally the most constant, we attach especial value to them; but if these same organs, in another group or section of a group, are found to differ much, we at once value them less in our classification. We shall hereafter, I think, clearly see why embryological characters are of such high classificatory importance. Geographical distribution may sometimes be brought usefully into play in classing large and widely-distributed genera, because all the species of the same genus, inhabiting any distinct and isolated region, have in all probability descended from the same parents.

We can understand, on these views, the very important distinction between real affinities and analogical or adaptive resemblances. Lamarck first called attention to this distinction, and he has been ably followed by Macleay and others. The resemblance, in the shape of the body and in the fin-like anterior limbs, between the dugong, which is a pachydermatous animal, and the whale, and between both these mammals and fishes, is analogical. Amongst insects there are innumerable instances: thus Linnaeus, misled by external appearances, actually classed an homopterous insect as a moth. We see something of the same kind even in our domestic varieties, as in the thickened stems of the common and swedish turnip. The resemblance of the greyhound and racehorse is hardly more fanciful than the analogies which have been drawn by some authors between very distinct animals. On my view of characters being of real importance for classification, only in so far as they reveal descent, we can clearly understand why analogical or adaptive character, although of the utmost importance to the welfare of the being, are almost valueless to the systematist. For animals, belonging to two most distinct lines of descent, may readily become adapted to similar conditions, and thus assume a close external resemblance; but such resemblances will not reveal will rather tend to conceal their blood-relationship to their proper lines of descent. We can also understand the apparent paradox, that the very same characters are analogical when one class or order is compared with another, but give true affinities when the members of the same class or order are compared one with another: thus the shape of the body and fin-like limbs are only analogical when whales are compared with fishes, being adaptations in both classes for swimming through the water; but the shape of the body and fin-like limbs serve as characters exhibiting true affinity between the several members of the whale family; for these cetaceans agree in so many characters, great and small, that we cannot doubt that they have inherited their general shape of body and structure of limbs from a common ancestor. So it is with fishes.

As members of distinct classes have often been adapted by successive slight modifications to live under nearly similar circumstances, to inhabit for instance the three elements of land, air, and water, we can perhaps understand how it is that a numerical parallelism has sometimes been observed between the sub-groups in distinct classes. A naturalist, struck by a parallelism of this nature in any one class, by arbitrarily raising or sinking the value of the groups in other classes (and all our experience shows that this valuation has hitherto been arbitrary), could easily extend the parallelism over a wide range; and thus the septenary, quinary, quaternary, and ternary classifications have probably arisen.

As the modified descendants of dominant species, belonging to the larger genera, tend to inherit the advantages, which made the groups to which they belong large and their parents dominant, they are almost sure to spread widely, and to seize on more and more places in the economy of nature. The larger and more dominant groups thus tend to go on increasing in size; and they consequently supplant many smaller and feebler groups. Thus we can account for the fact that all organisms, recent and extinct, are included under a few great orders, under still fewer classes, and all in one great natural system. As showing how few the higher groups are in number, and how widely spread they are throughout the world, the fact is striking, that the discovery of Australia has not added a single insect belonging to a new order; and that in the vegetable kingdom, as I learn from Dr. Hooker, it has added only two or three orders of small size.

In the chapter on geological succession I attempted to show, on the principle of each group having generally diverged much in character during the long-continued process of modification, how it is that the more ancient forms of life often present characters in some slight degree intermediate between existing groups. A few old and intermediate parent-forms having occasionally transmitted to the present day descendants but little modified, will give to us our so-called osculant or aberrant groups. The more aberrant any form is, the greater must be the number of connecting forms which on my theory have been exterminated and utterly lost. And we have some evidence of aberrant forms having suffered severely from extinction, for they are generally represented by extremely few species; and such species as do occur are generally very distinct from each other, which again implies extinction. The genera Ornithorhynchus and Lepidosiren, for example, would not have been less aberrant had each been represented by a dozen species instead of by a single one; but such richness in species, as I find after some investigation, does not commonly fall to the lot of aberrant genera. We can, I think, account for this fact only by looking at aberrant forms as failing groups conquered by more successful competitors, with a few members preserved by some unusual coincidence of favourable circumstances.

Mr. Waterhouse has remarked that, when a member belonging to one group of animals exhibits an affinity to a quite distinct group, this affinity in most cases is general and not special: thus, according to Mr. Waterhouse, of all Rodents, the bizcacha is most nearly related to Marsupials; but in the points in which it approaches this order, its relations are general, and not to any one marsupial species more than to another. As the points of affinity of the bizcacha to Marsupials are believed to be real and not merely adaptive, they are due on my theory to inheritance in common. Therefore we must suppose either that all Rodents, including the bizcacha, branched off from some very ancient Marsupial, which will have had a character in some degree intermediate with respect to all existing Marsupials; or that both Rodents and Marsupials branched off from a common progenitor, and that both groups have since undergone much modification in divergent directions. On either view we may suppose that the bizcacha has retained, by inheritance, more of the character of its ancient progenitor than have other Rodents; and therefore it will not be specially related to any one existing Marsupial, but indirectly to all or nearly all Marsupials, from having partially retained the character of their common progenitor, or of an early member of the group. On the other hand, of all Marsupials, as Mr. Waterhouse has remarked, the phascolomys resembles most nearly, not any one species, but the general order of Rodents. In this case, however, it may be strongly suspected that the resemblance is only analogical, owing to the phascolomys having become adapted to habits like those of a Rodent. The elder De Candolle has made nearly similar observations on the general nature of the affinities of distinct orders of plants.

On the principle of the multiplication and gradual divergence in character of the species descended from a common parent, together with their retention by inheritance of some characters in common, we can understand the excessively complex and radiating affinities by which all the members of the same family or higher group are connected together. For the common parent of a whole family of species, now broken up by extinction into distinct groups and sub-groups, will have transmitted some of its characters, modified in various ways and degrees, to all; and the several species will consequently be related to each other by circuitous lines of affinity of various lengths (as may be seen in the diagram so often referred to), mounting up through many predecessors. As it is difficult to show the blood-relationship between the numerous kindred of any ancient and noble family, even by the aid of a genealogical tree, and almost impossible to do this without this aid, we can understand the extraordinary difficulty which naturalists have experienced in describing, without the aid of a diagram, the various affinities which they perceive between the many living and extinct members of the same great natural class.

Extinction, as we have seen in the fourth chapter, has played an important part in defining and widening the intervals between the several groups in each class. We may thus account even for the distinctness of whole classes from each other for instance, of birds from all other vertebrate animals by the belief that many ancient forms of life have been utterly lost, through which the early progenitors of birds were formerly connected with the early progenitors of the other vertebrate classes. There has been less entire extinction of the forms of life which once connected fishes with batrachians. There has been still less in some other classes, as in that of the Crustacea, for here the most wonderfully diverse forms are still tied together by a long, but broken, chain of affinities. Extinction has only separated groups: it has by no means made them; for if every form which has ever lived on this earth were suddenly to reappear, though it would be quite impossible to give definitions by which each group could be distinguished from other groups, as all would blend together by steps as fine as those between the finest existing varieties, nevertheless a natural classification, or at least a natural arrangement, would be possible. We shall see this by turning to the diagram: the letters, A to L, may represent eleven Silurian genera, some of which have produced large groups of modified descendants. Every intermediate link between these eleven genera and their primordial parent, and every intermediate link in each branch and sub-branch of their descendants, may be supposed to be still alive; and the links to be as fine as those between the finest varieties. In this case it would be quite impossible to give any definition by which the several members of the several groups could be distinguished from their more immediate parents; or these parents from their ancient and unknown progenitor. Yet the natural arrangement in the diagram would still hold good; and, on the principle of inheritance, all the forms descended from A, or from I, would have something in common. In a tree we can specify this or that branch, though at the actual fork the two unite and blend together. We could not, as I have said, define the several groups; but we could pick out types, or forms, representing most of the characters of each group, whether large or small, and thus give a general idea of the value of the differences between them. This is what we should be driven to, if we were ever to succeed in collecting all the forms in any class which have lived throughout all time and space. We shall certainly never succeed in making so perfect a collection: nevertheless, in certain classes, we are tending in this direction; and Milne Edwards has lately insisted, in an able paper, on the high importance of looking to types, whether or not we can separate and define the groups to which such types belong.

Finally, we have seen that natural selection, which results from the struggle for existence, and which almost inevitably induces extinction and divergence of character in the many descendants from one dominant parent-species, explains that great and universal feature in the affinities of all organic beings, namely, their subordination in group under group. We use the element of descent in classing the individuals of both sexes and of all ages, although having few characters in common, under one species; we use descent in classing acknowledged varieties, however different they may be from their parent; and I believe this element of descent is the hidden bond of connexion which naturalists have sought under the term of the Natural System. On this idea of the natural system being, in so far as it has been perfected, genealogical in its arrangement, with the grades of difference between the descendants from a common parent, expressed by the terms genera, families, orders, &c., we can understand the rules which we are compelled to follow in our classification. We can understand why we value certain resemblances far more than others; why we are permitted to use rudimentary and useless organs, or others of trifling physiological importance; why, in comparing one group with a distinct group, we summarily reject analogical or adaptive characters, and yet use these same characters within the limits of the same group. We can clearly see how it is that all living and extinct forms can be grouped together in one great system; and how the several members of each class are connected together by the most complex and radiating lines of affinities. We shall never, probably, disentangle the inextricable web of affinities between the members of any one class; but when we have a distinct object in view, and do not look to some unknown plan of creation, we may hope to make sure but slow progress.

Morphology

We have seen that the members of the same class, independently of their habits of life, resemble each other in the general plan of their organisation. This resemblance is often expressed by the term `unity of type;' or by saying that the several parts and organs in the different species of the class are homologous. The whole subject is included under the general name of Morphology. This is the most interesting department of natural history, and may be said to be its very soul. What can be more curious than that the hand of a man, formed for grasping, that of a mole for digging, the leg of the horse, the paddle of the porpoise, and the wing of the bat, should all be constructed on the same pattern, and should include the same bones, in the same relative positions? Geoffroy St Hilaire has insisted strongly on the high importance of relative connexion in homologous organs: the parts may change to almost any extent in form and size, and yet they always remain connected together in the same order. We never find, for instance, the bones of the arm and forearm, or of the thigh and leg, transposed. Hence the same names can be given to the homologous bones in widely different animals. We see the same great law in the construction of the mouths of insects: what can be more different than the immensely long spiral proboscis of a sphinx-moth, the curious folded one of a bee or bug, and the great jaws of a beetle? yet all these organs, serving for such different purposes, are formed by infinitely numerous modifications of an upper lip, mandibles, and two pairs of maxillae. Analogous laws govern the construction of the mouths and limbs of crustaceans. So it is with the flowers of plants.

Nothing can be more hopeless than to attempt to explain this similarity of pattern in members of the same class, by utility or by the doctrine of final causes. The hopelessness of the attempt has been expressly admitted by Owen in his most interesting work on the `Nature of Limbs.' On the ordinary view of the independent creation of each being, we can only say that so it is; that it has so pleased the Creator to construct each animal and plant.

The explanation is manifest on the theory of the natural selection of successive slight modifications, each modification being profitable in some way to the modified form, but often affecting by correlation of growth other parts of the organisation. In changes of this nature, there will be little or no tendency to modify the original pattern, or to transpose parts. The bones of a limb might be shortened and widened to any extent, and become gradually enveloped in thick membrane, so as to serve as a fin; or a webbed foot might have all its bones, or certain bones, lengthened to any extent, and the membrane connecting them increased to any extent, so as to serve as a wing: yet in all this great amount of modification there will be no tendency to alter the framework of bones or the relative connexion of the several parts. If we suppose that the ancient progenitor, the archetype as it may be called, of all mammals, had its limbs constructed on the existing general pattern, for whatever purpose they served, we can at once perceive the plain signification of the homologous construction of the limbs throughout the whole class. So with the mouths of insects, we have only to suppose that their common progenitor had an upper lip, mandibles, and two pair of maxillae, these parts being perhaps very simple in form; and then natural selection will account for the infinite diversity in structure and function of the mouths of insects. Nevertheless, it is conceivable that the general pattern of an organ might become so much obscured as to be finally lost, by the atrophy and ultimately by the complete abortion of certain parts, by the soldering together of other parts, and by the doubling or multiplication of others, variations which we know to be within the limits of possibility. In the paddles of the extinct gigantic sea-lizards, and in the mouths of certain suctorial crustaceans, the general pattern seems to have been thus to a certain extent obscured.

There is another and equally curious branch of the present subject; namely, the comparison not of the same part in different members of a class, but of the different parts or organs in the same individual. Most physiologists believe that the bones of the skull are homologous with that is correspond in number and in relative connexion with the elemental parts of a certain number of vertebrae. The anterior and posterior limbs in each member of the vertebrate and articulate classes are plainly homologous. We see the same law in comparing the wonderfully complex jaws and legs in crustaceans. It is familiar to almost every one, that in a flower the relative position of the sepals, petals, stamens, and pistils, as well as their intimate structure, are intelligible in the view that they consist of metamorphosed leaves, arranged in a spire. In monstrous plants, we often get direct evidence of the possibility of one organ being transformed into another; and we can actually see in embryonic crustaceans and in many other animals, and in flowers, that organs which when mature become extremely different, are at an early stage of growth exactly alike.

How inexplicable are these facts on the ordinary view of creation! Why should the brain be enclosed in a box composed of such numerous and such extraordinarily shaped pieces of bone? As Owen has remarked, the benefit derived from the yielding of the separate pieces in the act of parturition of mammals, will by no means explain the same construction in the skulls of birds. Why should similar bones have been created in the formation of the wing and leg of a bat, used as they are for such totally different purposes? Why should one crustacean, which has an extremely complex mouth formed of many parts, consequently always have fewer legs; or conversely, those with many legs have simpler mouths? Why should the sepals, petals, stamens, and pistils in any individual flower, though fitted for such widely different purposes, be all constructed on the same pattern ?

On the theory of natural selection, we can satisfactorily answer these questions. In the vertebrata, we see a series of internal vertebrae bearing certain processes and appendages; in the articulata, we see the body divided into a series of segments, bearing external appendages; and in flowering plants, we see a series of successive spiral whorls of leaves. An indefinite repetition of the same part or organ is the common characteristic (as Owen has observed) of all low or little-modified forms; therefore we may readily believe that the unknown progenitor of the vertebrata possessed many vertebrae; the unknown progenitor of the articulata, many segments; and the unknown progenitor of flowering plants, many spiral whorls of leaves. We have formerly seen that parts many times repeated are eminently liable to vary in number and structure; consequently it is quite probable that natural selection, during a long-continued course of modification, should have seized on a certain number of the primordially similar elements, many times repeated, and have adapted them to the most diverse purposes. And as the whole amount of modification will have been effected by slight successive steps, we need not wonder at discovering in such parts or organs, a certain degree of fundamental resemblance, retained by the strong principle of inheritance.

In the great class of molluscs, though we can homologise the parts of one species with those of another and distinct species, we can indicate but few serial homologies; that is, we are seldom enabled to say that one part or organ is homologous with another in the same individual. And we can understand this fact; for in molluscs, even in the lowest members of the class, we do not find nearly so much indefinite repetition of any one part, as we find in the other great classes of the animal and vegetable kingdoms.

Naturalists frequently speak of the skull as formed of metamorphosed vertebrae: the jaws of crabs as metamorphosed legs; the stamens and pistils of flowers as metamorphosed leaves; but it would in these cases probably be more correct, as Professor Huxley has remarked, to speak of both skull and vertebrae, both jaws and legs, &c., as having been metamorphosed, not one from the other, but from some common element. Naturalists, however, use such language only in a metaphorical sense: they are far from meaning that during a long course of descent, primordial organs of any kind vertebrae in the one case and legs in the other have actually been modified into skulls or jaws. Yet so strong is the appearance of a modification of this nature having occurred, that naturalists can hardly avoid employing language having this plain signification. On my view these terms may be used literally; and the wonderful fact of the jaws, for instance, of a crab retaining numerous characters, which they would probably have retained through inheritance, if they had really been metamorphosed during a long course of descent from true legs, or from some simple appendage, is explained.
Embryology

It has already been casually remarked that certain organs in the individual, which when mature become widely different and serve for different purposes, are in the embryo exactly alike. The embryos, also, of distinct animals within the same class are often strikingly similar: a better proof of this cannot be given, than a circumstance mentioned by Agassiz, namely, that having forgotten to ticket the embryo of some vertebrate animal, he cannot now tell whether it be that of a mammal, bird, or reptile. The vermiform larvae of moths, flies, beetles, &c., resemble each other much more closely than do the mature insects; but in the case of larvae, the embryos are active, and have been adapted for special lines of life. A trace of the law of embryonic resemblance, sometimes lasts till a rather late age: thus birds of the same genus, and of closely allied genera, often resemble each other in their first and second plumage; as we see in the spotted feathers in the thrush group. In the cat tribe, most of the species are striped or spotted in lines; and stripes can be plainly distinguished in the whelp of the lion. We occasionally though rarely see something of this kind in plants: thus the embryonic leaves of the ulex or furze, and the first leaves of the phyllodineous acaceas, are pinnate or divided like the ordinary leaves of the leguminosae.

The points of structure, in which the embryos of widely different animals of the same class resemble each other, often have no direct relation to their conditions of existence. We cannot, for instance, suppose that in the embryos of the vertebrata the peculiar loop-like course of the arteries near the branchial slits are related to similar conditions, in the young mammal which is nourished in the womb of its mother, in the egg of the bird which is hatched in a nest, and in the spawn of a frog under water. We have no more reason to believe in such a relation, than we have to believe that the same bones in the hand of a man, wing of a bat, and fin of a porpoise, are related to similar conditions of life. No one will suppose that the stripes on the whelp of a lion, or the spots on the young blackbird, are of any use to these animals, or are related to the conditions to which they are exposed.

The case, however, is different when an animal during any part of its embryonic career is active, and has to provide for itself. The period of activity may come on earlier or later in life; but whenever it comes on, the adaptation of the larva to its conditions of life is just as perfect and as beautiful as in the adult animal. From such special adaptations, the similarity of the larvae or active embryos of allied animals is sometimes much obscured; and cases could be given of the larvae of two species, or of two groups of species, differing quite as much, or even more, from each other than do their adult parents. In most cases, however, the larvae, though active, still obey more or less closely the law of common embryonic resemblance. Cirripedes afford a good instance of this: even the illustrious Cuvier did not perceive that a barnacle was, as it certainly is, a crustacean; but a glance at the larva shows this to be the case in an unmistakeable manner. So again the two main divisions of cirripedes, the pedunculated and sessile, which differ widely in external appearance, have larvae in all their several stages barely distinguishable.

The embryo in the course of development generally rises in organisation: I use this expression, though I am aware that it is hardly possible to define clearly what is meant by the organisation being higher or lower. But no one probably will dispute that the butterfly is higher than the caterpillar. In some cases, however, the mature animal is generally considered as lower in the scale than the larva, as with certain parasitic crustaceans. To refer once again to cirripedes: the larvae in the first stage have three pairs of legs, a very simple single eye, and a probosciformed mouth, with which they feed largely, for they increase much in size. In the second stage, answering to the chrysalis stage of butterflies, they have six pairs of beautifully constructed natatory legs, a pair of magnificent compound eyes, and extremely complex antennae; but they have a closed and imperfect mouth, and cannot feed: their function at this stage is, to search by their well-developed organs of sense, and to reach by their active powers of swimming, a proper place on which to become attached and to undergo their final metamorphosis. When this is completed they are fixed for life: their legs are now converted into prehensile organs; they again obtain a well-constructed mouth; but they have no antennae, and their two eyes are now reconverted into a minute, single, and very simple eye-spot. In this last and complete state, cirripedes may be considered as either more highly or more lowly organised than they were in the larval condition. But in some genera the larvae become developed either into hermaphrodites having the ordinary structure, or into what I have called complemental males: and in the latter, the development has assuredly been retrograde; for the male is a mere sack, which lives for a short time, and is destitute of mouth, stomach, or other organ of importance, excepting for reproduction.

We are so much accustomed to see differences in structure between the embryo and the adult, and likewise a close similarity in the embryos of widely different animals within the same class, that we might be led to look at these facts as necessarily contingent in some manner on growth. But there is no obvious reason why, for instance, the wing of a bat, or the fin of a porpoise, should not have been sketched out with all the parts in proper proportion, as soon as any structure became visible in the embryo. And in some whole groups of animals and in certain members of other groups, the embryo does not at any period differ widely from the adult: thus Owen has remarked in regard to cuttle-fish, `there is no metamorphosis; the cephalopodic character is manifested long before the parts of the embryo are completed;' and again in spiders, `there is nothing worthy to be called a metamorphosis.' The larvae of insects, whether adapted to the most diverse and active habits, or quite inactive, being fed by their parents or placed in the midst of proper nutriment, yet nearly all pass through a similar worm-like stage of development; but in some few cases, as in that of Aphis, if we look to the admirable drawings by Professor Huxley of the development of this insect, we see no trace of the vermiform stage.

How, then, can we explain these several facts in embryology, namely the very general, but not universal difference in structure between the embryo and the adult; of parts in the same individual embryo, which ultimately become very unlike and serve for diverse purposes, being at this early period of growth alike; of embryos of different species within the same class, generally, but not universally, resembling each other; of the structure of the embryo not being closely related to its conditions of existence, except when the embryo becomes at any period of life active and has to provide for itself; of the embryo apparently having sometimes a higher organisation than the mature animal, into which it is developed. I believe that all these facts can be explained, as follows, on the view of descent with modification.

It is commonly assumed, perhaps from monstrosities often affecting the embryo at a very early period, that slight variations necessarily appear at an equally early period. But we have little evidence on this head indeed the evidence rather points the other way; for it is notorious that breeders of cattle, horses, and various fancy animals, cannot positively tell, until some time after the animal has been born, what its merits or form will ultimately turn out. We see this plainly in our own children; we cannot always tell whether the child will be tall or short, or what its precise features will be. The question is not, at what period of life any variation has been caused, but at what period it is fully displayed. The cause may have acted, and I believe generally has acted, even before the embryo is formed; and the variation may be due to the male and female sexual elements having been affected by the conditions to which either parent, or their ancestors, have been exposed. Nevertheless an effect thus caused at a very early period, even before the formation of the embryo, may appear late in life; as when an hereditary disease, which appears in old age alone, has been communicated to the offspring from the reproductive element of one parent. Or again, as when the horns of cross-bred cattle have been affected by the shape of the horns of either parent. For the welfare of a very young animal, as long as it remains in its mother's womb, or in the egg, or as long as it is nourished and protected by its parent, it must be quite unimportant whether most of its characters are fully acquired a little earlier or later in life. It would not signify, for instance, to a bird which obtained its food best by having a long beak, whether or not it assumed a beak of this particular length, as long as it was fed by its parents. Hence, I conclude, that it is quite possible, that each of the many successive modifications, by which each species has acquired its present structure, may have supervened at a not very early period of life; and some direct evidence from our domestic animals supports this view. But in other cases it is quite possible that each successive modification, or most of them, may have appeared at an extremely early period.

I have stated in the first chapter, that there is some evidence to render it probable, that at whatever age any variation first appears in the parent, it tends to reappear at a corresponding age in the offspring. Certain variations can only appear at corresponding ages, for instance, peculiarities in the caterpillar, cocoon, or imago states of the silk-moth; or, again, in the horns of almost full-grown cattle. But further than this, variations which, for all that we can see, might have appeared earlier or later in life, tend to appear at a corresponding age in the offspring and parent. I am far from meaning that this is invariably the case; and I could give a good many cases of variations (taking the word in the largest sense) which have supervened at an earlier age in the child than in the parent.

These two principles, if their truth be admitted, will, I believe, explain all the above specified leading facts in embryology. But first let us look at a few analogous cases in domestic varieties. Some authors who have written on Dogs, maintain that the greyhound and bulldog, though appearing so different, are really varieties most closely allied, and have probably descended from the same wild stock; hence I was curious to see how far their puppies differed from each other: I was told by breeders that they differed just as much as their parents, and this, judging by the eye, seemed almost to be the case; but on actually measuring the old dogs and their six-days old puppies, I found that the puppies had not nearly acquired their full amount of proportional difference. So, again, I was told that the foals of cart and race-horses differed as much as the full-grown animals; and this surprised me greatly, as I think it probable that the difference between these two breeds has been wholly caused by selection under domestication; but having had careful measurements made of the dam and of a three-days old colt of a race and heavy cart-horse, I find that the colts have by no means acquired their full amount of proportional difference.

As the evidence appears to me conclusive, that the several domestic breeds of pigeon have descended from one wild species, I compared young pigeons of various breeds, within twelve hours after being hatched; I carefully measured the proportions (but will not here give details) of the beak, width of mouth, length of nostril and of eyelid, size of feet and length of leg, in the wild stock, in pouters, fantails, runts, barbs, dragons, carriers, and tumblers. Now some of these birds, when mature, differ so extraordinarily in length and form of beak, that they would, I cannot doubt, be ranked in distinct genera, had they been natural productions. But when the nestling birds of these several breeds were placed in a row, though most of them could be distinguished from each other, yet their proportional differences in the above specified several points were incomparably less than in the full-grown birds. Some characteristic points of difference for instance, that of the width of mouth -- could hardly be detected in the young. But there was one remarkable exception to this rule, for the young of the short-faced tumbler differed from the young of the wild rock-pigeon and of the other breeds, in all its proportions, almost exactly as much as in the adult state.

The two principles above given seem to me to explain these facts in regard to the later embryonic stages of our domestic varieties. Fanciers select their horses, dogs, and pigeons, for breeding, when they are nearly grown up: they are indifferent whether the desired qualities and structures have been acquired earlier or later in life, if the full-grown animal possesses them. And the cases just given, more especially that of pigeons, seem to show that the characteristic differences which give value to each breed, and which have been accumulated by man's selection, have not generally first appeared at an early period of life, and have been inherited by the offspring at a corresponding not early period. But the case of the short-faced tumbler, which when twelve hours old had acquired its proper proportions, proves that this is not the universal rule; for here the characteristic differences must either have appeared at an earlier period than usual, or, if not so, the differences must have been inherited, not at the corresponding, but at an earlier age.

Now let us apply these facts and the above two principles which latter, though not proved true, can be shown to be in some degree probable to species in a state of nature. Let us take a genus of birds, descended on my theory from some one parent-species, and of which the several new species have become modified through natural selection in accordance with their diverse habits. Then, from the many slight successive steps of variation having supervened at a rather late age, and having been inherited at a corresponding age, the young of the new species of our supposed genus will manifestly tend to resemble each other much more closely than do the adults, just as we have seen in the case of pigeons. We may extend this view to whole families or even classes. The fore-limbs, for instance, which served as legs in the parent-species, may become, by a long course of modification, adapted in one descendant to act as hands, in another as paddles, in another as wings; and on the above two principles namely of each successive modification supervening at a rather late age, and being inherited at a corresponding late age the fore-limbs in the embryos of the several descendants of the parent-species will still resemble each other closely, for they will not have been modified. But in each individual new species, the embryonic fore-limbs will differ greatly from the fore-limbs in the mature animal; the limbs in the latter having undergone much modification at a rather late period of life, and having thus been converted into hands, or paddles, or wings. Whatever influence long-continued exercise or use on the one hand, and disuse on the other, may have in modifying an organ, such influence will mainly affect the mature animal, which has come to its full powers of activity and has to gain its own living; and the effects thus produced will be inherited at a corresponding mature age. Whereas the young will remain unmodified, or be modified in a lesser degree, by the effects of use and disuse.

In certain cases the successive steps of variation might supervene, from causes of which we are wholly ignorant, at a very early period of life, or each step might be inherited at an earlier period than that at which it first appeared. In either case (as with the short-faced tumbler) the young or embryo would closely resemble the mature parent-form. We have seen that this is the rule of development in certain whole groups of animals, as with cuttle-fish and spiders, and with a few members of the great class of insects, as with Aphis. With respect to the final cause of the young in these cases not undergoing any metamorphosis, or closely resembling their parents from their earliest age, we can see that this would result from the two following contingencies; firstly, from the young, during a course of modification carried on for many generations, having to provide for their own wants at a very early stage of development, and secondly, from their following exactly the same habits of life with their parents; for in this case, it would be indispensable for the existence of the species, that the child should be modified at a very early age in the same manner with its parents, in accordance with their similar habits. Some further explanation, however, of the embryo not undergoing any metamorphosis is perhaps requisite. If, on the other hand, it profited the young to follow habits of life in any degree different from those of their parent, and consequently to be constructed in a slightly different manner, then, on the principle of inheritance at corresponding ages, the active young or larvae might easily be rendered by natural selection different to any conceivable extent from their parents. Such differences might, also, become correlated with successive stages of development; so that the larvae, in the first stage, might differ greatly from the larvae in the second stage, as we have seen to be the case with cirripedes. The adult might become fitted for sites or habits, in which organs of locomotion or of the senses, &c., would be useless; and in this case the final metamorphosis would be said to be retrograde.

As all the organic beings, extinct and recent, which have ever lived on this earth have to be classed together, and as all have been connected by the finest gradations, the best, or indeed, if our collections were nearly perfect, the only possible arrangement, would be genealogical. Descent being on my view the hidden bond of connexion which naturalists have been seeking under the term of the natural system. On this view we can understand how it is that, in the eyes of most naturalists, the structure of the embryo is even more important for classification than that of the adult. For the embryo is the animal in its less modified state; and in so far it reveals the structure of its progenitor. In two groups of animal, however much they may at present differ from each other in structure and habits, if they pass through the same or similar embryonic stages, we may feel assured that they have both descended from the same or nearly similar parents, and are therefore in that degree closely related. Thus, community in embryonic structure reveals community of descent. It will reveal this community of descent, however much the structure of the adult may have been modified and obscured; we have seen, for instance, that cirripedes can at once be recognised by their larvae as belonging to the great class of crustaceans. As the embryonic state of each species and group of species partially shows us the structure of their less modified ancient progenitors, we can clearly see why ancient and extinct forms of life should resemble the embryos of their descendants, our existing species. Agassiz believes this to be a law of nature; but I am bound to confess that I only hope to see the law hereafter proved true. It can be proved true in those cases alone in which the ancient state, now supposed to be represented in many embryos, has not been obliterated, either by the successive variations in a long course of modification having supervened at a very early age, or by the variations having been inherited at an earlier period than that at which they first appeared. It should also be borne in mind, that the supposed law of resemblance of ancient forms of life to the embryonic stages of recent forms, may be true, but yet, owing to the geological record not extending far enough back in time, may remain for a long period, or for ever, incapable of demonstration.

Thus, as it seems to me, the leading facts in embryology, which are second in importance to none in natural history, are explained on the principle of slight modifications not appearing, in the many descendants from some one ancient progenitor, at a very early period in the life of each, though perhaps caused at the earliest, and being inherited at a corresponding not early period. Embryology rises greatly in interest, when we thus look at the embryo as a picture, more or less obscured, of the common parent-form of each great class of animals.
Rudimentary, atrophied, or aborted organs

Organs or parts in this strange condition, bearing the stamp of inutility, are extremely common throughout nature. For instance, rudimentary mammae are very general in the males of mammals: I presume that the `bastard-wing' in birds may be safely considered as a digit in a rudimentary state: in very many snakes one lobe of the lungs is rudimentary; in other snakes there are rudiments of the pelvis and hind limbs. Some of the cases of rudimentary organs are extremely curious; for instance, the presence of teeth in foetal whales, which when grown up have not a tooth in their heads; and the presence of teeth, which never cut through the gums, in the upper jaws of our unborn calves. It has even been stated on good authority that rudiments of teeth can be detected in the beaks of certain embryonic birds. Nothing can be plainer than that wings are formed for flight, yet in how many insects do we see wings so reduced in size as to be utterly incapable of flight, and not rarely lying under wing-cases, firmly soldered together!

The meaning of rudimentary organs is often quite unmistakeable: for instance there are beetles of the same genus (and even of the same species) resembling each other most closely in all respects, one of which will have full-sized wings, and another mere rudiments of membrane; and here it is impossible to doubt, that the rudiments represent wings. Rudimentary organs sometimes retain their potentiality, and are merely not developed: this seems to be the case with the mammae of male mammals, for many instances are on record of these organs having become well developed in full-grown males, and having secreted milk. So again there are normally four developed and two rudimentary teats in the udders of the genus Bos, but in our domestic cows the two sometimes become developed and give milk. In individual plants of the same species the petals sometimes occur as mere rudiments, and sometimes in a well-developed state. In plants with separated sexes, the male flowers often have a rudiment of a pistil; and Kölreuter found that by crossing such male plants with an hermaphrodite species, the rudiment of the pistil in the hybrid offspring was much increased in size; and this shows that the rudiment and the perfect pistil are essentially alike in nature.

An organ serving for two purposes, may become rudimentary or utterly aborted for one, even the more important purpose;, and remain perfectly efficient for the other. Thus in plants, the office of the pistil is to allow the pollen-tubes to reach the ovules protected in the ovarium at its base. The pistil consists of a stigma supported on the style; but in some Compositae, the male florets, which of course cannot be fecundated, have a pistil, which is in a rudimentary state, for it is not crowned with a stigma; but the style remains well developed, and is clothed with hairs as in other compositae, for the purpose of brushing the pollen out of the surrounding anthers. Again, an organ may become rudimentary for its proper purpose, and be used for a distinct object: in certain fish the swim-bladder seems to be rudimentary for its proper function of giving buoyancy, but has become converted into a nascent breathing organ or lung. Other similar instances could be given.

Rudimentary organs in the individuals of the same species are very liable to vary in degree of development and in other respects. Moreover, in closely allied species, the degree to which the same organ has been rendered rudimentary occasionally differs much. This latter fact is well exemplified in the state of the wings of the female moths in certain groups. Rudimentary organs may be utterly aborted; and this implies, that we find in an animal or plant no trace of an organ, which analogy would lead us to expect to find, and which is occasionally found in monstrous individuals of the species. Thus in the snapdragon (antirrhinum) we generally do not find a rudiment of a fifth stamen; but this may sometimes be seen. In tracing the homologies of the same part in different members of a class, nothing is more common, or more necessary, than the use and discovery of rudiments. This is well shown in the drawings given by Owen of the bones of the leg of the horse, ox, and rhinoceros.

It is an important fact that rudimentary organs, such as teeth in the upper jaws of whales and ruminants, can often be detected in the embryo, but afterwards wholly disappear. It is also, I believe, a universal rule, that a rudimentary part or organ is of greater size relatively to the adjoining parts in the embryo, than in the adult; so that the organ at this early age is less rudimentary, or even cannot be said to be in any degree rudimentary. Hence, also, a rudimentary organ in the adult, is often said to have retained its embryonic condition.

I have now given the leading facts with respect to rudimentary organs. In reflecting on them, every one must be struck with astonishment: for the same reasoning power which tells us plainly that most parts and organs are exquisitely adapted for certain purposes, tells us with equal plainness that these rudimentary or atrophied organs, are imperfect and useless. In works on natural history rudimentary organs are generally said to have been created `for the sake of symmetry,' or in order `to complete the scheme of nature;' but this seems to me no explanation, merely a restatement of the fact. Would it be thought sufficient to say that because planets revolve in elliptic courses round the sun, satellites follow the same course round the planets, for the sake of symmetry, and to complete the scheme of nature? An eminent physiologist accounts for the presence of rudimentary organs, by supposing that they serve to excrete matter in excess, or injurious to the system; but can we suppose that the minute papilla, which often represents the pistil in male flowers, and which is formed merely of cellular tissue, can thus act? Can we suppose that the formation of rudimentary teeth which are subsequently absorbed, can be of any service to the rapidly growing embryonic calf by the excretion of precious phosphate of lime? When a man's fingers have been amputated, imperfect nails sometimes appear on the stumps: I could as soon believe that these vestiges of nails have appeared, not from unknown laws of growth, but in order to excrete horny matter, as that the rudimentary nails on the fin of the manatee were formed for this purpose.

On my view of descent with modification, the origin of rudimentary organs is simple. We have plenty of cases of rudimentary organs in our domestic productions, as the stump of a tail in tailless breeds, the vestige of an ear in earless breeds, -- the reappearance of minute dangling horns in hornless breeds of cattle, more especially, according to Youatt, in young animals, and the state of the whole flower in the cauliflower. We often see rudiments of various parts in monsters. But I doubt whether any of these cases throw light on the origin of rudimentary organs in a state of nature, further than by showing that rudiments can be produced; for I doubt whether species under nature ever undergo abrupt changes. I believe that disuse has been the main agency; that it has led in successive generations to the gradual reduction of various organs, until they have become rudimentary, as in the case of the eyes of animals inhabiting dark caverns, and of the wings of birds inhabiting oceanic islands, which have seldom been forced to take flight, and have ultimately lost the power of flying. Again, an organ useful under certain conditions, might become injurious under others, as with the wings of beetles living on small and exposed islands; and in this case natural selection would continue slowly to reduce the organ, until it was rendered harmless and rudimentary.

Any change in function, which can be effected by insensibly small steps, is within the power of natural selection; so that an organ rendered, during changed habits of life, useless or injurious for one purpose, might easily be modified and used for another purpose. Or an organ might be retained for one alone of its former functions. An organ, when rendered useless, may well be variable, for its variations cannot be checked by natural selection. At whatever period of life disuse or selection reduces an organ, and this will generally be when the being has come to maturity and to its full powers of action, the principle of inheritance at corresponding ages will reproduce the organ in its reduced state at the same age, and consequently will seldom affect or reduce it in the embryo. Thus we can understand the greater relative size of rudimentary organs in the embryo, and their lesser relative size in the adult. But if each step of the process of reduction were to be inherited, not at the corresponding age, but at an extremely early period of life (as we have good reason to believe to be possible) the rudimentary part would tend to be wholly lost, and we should have a case of complete abortion. The principle, also, of economy, explained in a former chapter, by which the materials forming any part or structure, if not useful to the possessor, will be saved as far as is possible, will probably often come into play; and this will tend to cause the entire obliteration of a rudimentary organ.

As the presence of rudimentary organs is thus due to the tendency in every part of the organisation, which has long existed, to be inherited we can understand, on the genealogical view of classification, how it is that systematists have found rudimentary parts as useful as, or even sometimes more useful than, parts of high physiological importance. Rudimentary organs may be compared with the letters in a word, still retained in the spelling, but become useless in the pronunciation, but which serve as a clue in seeking for its derivation. On the view of descent with modification, we may conclude that the existence of organs in a rudimentary, imperfect, and useless condition, or quite aborted, far from presenting a strange difficulty, as they assuredly do on the ordinary doctrine of creation, might even have been anticipated, and can be accounted for by the laws of inheritance.
Summary

In this chapter I have attempted to show, that the subordination of group to group in all organisms throughout all time; that the nature of the relationship, by which all living and extinct beings are united by complex, radiating, and circuitous lines of affinities into one grand system; the rules followed and the difficulties encountered by naturalists in their classifications; the value set upon characters, if constant and prevalent, whether of high vital importance, or of the most trifling importance, or, as in rudimentary organs, of no importance; the wide opposition in value between analogical or adaptive characters, and characters of true affinity; and other such rules; all naturally follow on the view of the common parentage of those forms which are considered by naturalists as allied, together with their modification through natural selection, with its contingencies of extinction and divergence of character. In considering this view of classification, it should be borne in mind that the element of descent has been universally used in ranking together the sexes, ages, and acknowledged varieties of the same species, however different they may be in structure. If we extend the use of this element of descent, the only certainly known cause of similarity in organic beings, we shall understand what is meant by the natural system: it is genealogical in its attempted arrangement, with the grades of acquired difference marked by the terms varieties, species, genera, families, orders, and classes.

On this same view of descent with modification, all the great facts in Morphology become intelligible, whether we look to the same pattern displayed in the homologous organs, to whatever purpose applied, of the different species of a class; or to the homologous parts constructed on the same pattern in each individual animal and plant.

On the principle of successive slight variations, not necessarily or generally supervening at a very early period of life, and being inherited at a corresponding period, we can understand the great leading facts in Embryology; namely, the resemblance in an individual embryo of the homologous parts, which when matured will become widely different from each other in structure and function; and the resemblance in different species of a class of the homologous parts or organs, though fitted in the adult members for purposes as different as possible. Larvae are active embryos, which have become specially modified in relation to their habits of life, through the principle of modifications being inherited at corresponding ages. On this same principle and bearing in mind, that when organs are reduced in size, either from disuse or selection, it will generally be at that period of life when the being has to provide for its own wants, and bearing in mind how strong is the principle of inheritance the occurrence of rudimentary organs and their final abortion, present to us no inexplicable difficulties; on the contrary, their presence might have been even anticipated. The importance of embryological characters and of rudimentary organs in classification is intelligible, on the view that an arrangement is only so far natural as it is genealogical.

Finally, the several classes of facts which have been considered in this chapter, seem to me to proclaim so plainly, that the innumerable species, genera, and families of organic beings, with which this world is peopled, have all descended, each within its own class or group, from common parents, and have all been modified in the course of descent, that I should without hesitation adopt this view, even if it were unsupported by other facts or arguments. 
As this whole volume is one long argument, it may be convenient to the reader to have the leading facts and inferences briefly recapitulated.

That many and grave objections may be advanced against the theory of descent with modification through natural selection, I do not deny. I have endeavoured to give to them their full force. Nothing at first can appear more difficult to believe than that the more complex organs and instincts should have been perfected not by means superior to, though analogous with, human reason, but by the accumulation of innumerable slight variations, each good for the individual possessor. Nevertheless, this difficulty, though appearing to our imagination insuperably great, cannot be considered real if we admit the following propositions, namely, -- that gradations in the perfection of any organ or instinct, which we may consider, either do now exist or could have existed, each good of its kind, -- that all organs and instincts are, in ever so slight a degree, variable, -- and, lastly, that there is a struggle for existence leading to the preservation of each profitable deviation of structure or instinct. The truth of these propositions cannot, I think, be disputed.

It is, no doubt, extremely difficult even to conjecture by what gradations many structures have been perfected, more especially amongst broken and failing groups of organic beings; but we see so many strange gradations in nature, as is proclaimed by the canon, `Natura non facit saltum,' that we ought to be extremely cautious in saying that any organ or instinct, or any whole being, could not have arrived at its present state by many graduated steps. There are, it must be admitted, cases of special difficulty on the theory of natural selection; and one of the most curious of these is the existence of two or three defined castes of workers or sterile females in the same community of ants but I have attempted to show how this difficulty can be mastered. With respect to the almost universal sterility of species when first crossed, which forms so remarkable a contrast with the almost universal fertility of varieties when crossed, I must refer the reader to the recapitulation of the facts given at the end of the eighth chapter, which seem to me conclusively to show that this sterility is no more a special endowment than is the incapacity of two trees to be grafted together, but that it is incidental on constitutional differences in the reproductive systems of the intercrossed species. We see the truth of this conclusion in the vast difference in the result, when the same two species are crossed reciprocally; that is, when one species is first used as the father and then as the mother.

The fertility of varieties when intercrossed and of their mongrel offspring cannot be considered as universal; nor is their very general fertility surprising when we remember that it is not likely that either their constitutions or their reproductive systems should have been profoundly modified. Moreover, most of the varieties which have been experimentised on have been produced under domestication; and as domestication apparently tends to eliminate sterility, we ought not to expect it also to produce sterility.

The sterility of hybrids is a very different case from that of first crosses, for their reproductive organs are more or less functionally impotent; whereas in first crosses the organs on both sides are in a perfect condition. As we continually see that organisms of all kinds are rendered in some degree sterile from their constitutions having been disturbed by slightly different and new conditions of life, we need not feel surprise at hybrids being in some degree sterile, for their constitutions can hardly fail to have been disturbed from being compounded of two distinct organisations. This parallelism is supported by another parallel, but directly opposite, class of facts; namely, that the vigour and fertility of all organic beings are increased by slight changes in their conditions of life, and that the offspring of slightly modified forms or varieties acquire from being crossed increased vigour and fertility. So that, on the one hand, considerable changes in the conditions of life and crosses between greatly modified forms, lessen fertility; and on the other hand, lesser changes in the conditions of life and crosses between less modified forms, increase fertility.

Turning to geographical distribution, the difficulties encountered on the theory of descent with modification are grave enough. All the individuals of the same species, and all the species of the same genus, or even higher group, must have descended from common parents; and therefore, in however distant and isolated parts of the world they are now found, they must in the course of successive generations have passed from some one part to the others. We are often wholly unable even to conjecture how this could have been effected. Yet, as we have reason to believe that some species have retained the same specific form for very long periods, enormously long as measured by years, too much stress ought not to be laid on the occasional wide diffusion of the same species; for during very long periods of time there will always be a good chance for wide migration by many means. A broken or interrupted range may often be accounted for by the extinction of the species in the intermediate regions. It cannot be denied that we are as yet very ignorant of the full extent of the various climatal and geographical changes which have affected the earth during modern periods; and such changes will obviously have greatly facilitated migration. As an example, I have attempted to show how potent has been the influence of the Glacial period on the distribution both of the same and of representative species throughout the world. We are as yet profoundly ignorant of the many occasional means of transport. With respect to distinct species of the same genus inhabiting very distant and isolated regions, as the process of modification has necessarily been slow, all the means of migration will have been possible during a very long period; and consequently the difficulty of the wide diffusion of species of the same genus is in some degree lessened.

As on the theory of natural selection an interminable number of intermediate forms must have existed, linking together all the species in each group by gradations as fine as our present varieties, it may be asked, Why do we not see these linking forms all around us? Why are not all organic beings blended together in an inextricable chaos? With respect to existing forms, we should remember that we have no right to expect (excepting in rare cases) to discover directly connecting links between them, but only between each and some extinct and supplanted form. Even on a wide area, which has during a long period remained continuous, and of which the climate and other conditions of life change insensibly in going from a district occupied by one species into another district occupied by a closely allied species, we have no just right to expect often to find intermediate varieties in the intermediate zone. For we have reason to believe that only a few species are undergoing change at any one period; and all changes are slowly effected. I have also shown that the intermediate varieties which will at first probably exist in the intermediate zones, will be liable to be supplanted by the allied forms on either hand; and the latter, from existing in greater numbers, will generally be modified and improved at a quicker rate than the intermediate varieties, which exist in lesser numbers; so that the intermediate varieties will, in the long run, be supplanted and exterminated.

On this doctrine of the extermination of an infinitude of connecting links, between the living and extinct inhabitants of the world, and at each successive period between the extinct and still older species, why is not every geological formation charged with such links? Why does not every collection of fossil remains afford plain evidence of the gradation and mutation of the forms of life? We meet with no such evidence, and this is the most obvious and forcible of the many objections which may be urged against my theory. Why, again, do whole groups of allied species appear, though certainly they often falsely appear, to have come in suddenly on the several geological stages? Why do we not find great piles of strata beneath the Silurian system, stored with the remains of the progenitors of the Silurian groups of fossils? For certainly on my theory such strata must somewhere have been deposited at these ancient and utterly unknown epochs in the world's history.

I can answer these questions and grave objections only on the supposition that the geological record is far more imperfect than most geologists believe. It cannot be objected that there has not been time sufficient for any amount of organic change; for the lapse of time has been so great as to be utterly inappreciable by the human intellect. The number of specimens in all our museums is absolutely as nothing compared with the countless generations of countless species which certainly have existed. We should not be able to recognise a species as the parent of any one or more species if we were to examine them ever so closely, unless we likewise possessed many of the intermediate links between their past or parent and present states; and these many links we could hardly ever expect to discover, owing to the imperfection of the geological record. Numerous existing doubtful forms could be named which are probably varieties; but who will pretend that in future ages so many fossil links will be discovered, that naturalists will be able to decide, on the common view, whether or not these doubtful forms are varieties? As long as most of the links between any two species are unknown, if any one link or intermediate variety be discovered, it will simply be classed as another and distinct species. Only a small portion of the world has been geologically explored. Only organic beings of certain classes can be preserved in a fossil condition, at least in any great number. Widely ranging species vary most, and varieties are often at first local, -- both causes rendering the discovery of intermediate links less likely. Local varieties will not spread into other and distant regions until they are considerably modified and improved; and when they do spread, if discovered in a geological formation, they will appear as if suddenly created there, and will be simply classed as new species. Most formations have been intermittent in their accumulation; and their duration, I am inclined to believe, has been shorter than the average duration of specific forms. Successive formations are separated from each other by enormous blank intervals of time; for fossiliferous formations, thick enough to resist future degradation, can be accumulated only where much sediment is deposited on the subsiding bed of the sea. During the alternate periods of elevation and of stationary level the record will be blank. During these latter periods there will probably be more variability in the forms of life; during periods of subsidence, more extinction.

With respect to the absence of fossiliferous formations beneath the lowest Silurian strata, I can only recur to the hypothesis given in the ninth chapter. That the geological record is imperfect all will admit; but that it is imperfect to the degree which I require, few will be inclined to admit. If we look to long enough intervals of time, geology plainly declares that all species have changed; and they have changed in the manner which my theory requires, for they have changed slowly and in a graduated manner. We clearly see this in the fossil remains from consecutive formations invariably being much more closely related to each other, than are the fossils from formations distant from each other in time.

Such is the sum of the several chief objections and difficulties which may justly be urged against my theory; and I have now briefly recapitulated the answers and explanations which can be given to them. I have felt these difficulties far too heavily during many years to doubt their weight. But it deserves especial notice that the more important objections relate to questions on which we are confessedly ignorant; nor do we know how ignorant we are. We do not know all the possible transitional gradations between the simplest and the most perfect organs; it cannot be pretended that we know all the varied means of Distribution during the long lapse of years, or that we know how imperfect the Geological Record is. Grave as these several difficulties are, in my judgement they do not overthrow the theory of descent with modification.

Now let us turn to the other side of the argument. Under domestication we see much variability. This seems to be mainly due to the reproductive system being eminently susceptible to changes in the conditions of life so that this system, when not rendered impotent, fails to reproduce offspring exactly like the parent-form. Variability is governed by many complex laws, -- by correlation of growth, by use and disuse, and by the direct action of the physical conditions of life. There is much difficulty in ascertaining how much modification our domestic productions have undergone; but we may safely infer that the amount has been large, and that modifications can be inherited for long periods. As long as the conditions of life remain the same, we have reason to believe that a modification, which has already been inherited for many generations, may continue to be inherited for an almost infinite number of generations. On the other hand we have evidence that variability, when it has once come into play, does not wholly cease; for new varieties are still occasionally produced by our most anciently domesticated productions.

Man does not actually produce variability; he only unintentionally exposes organic beings to new conditions of life, and then nature acts on the organisation, and causes variability. But man can and does select the variations given to him by nature, and thus accumulate them in any desired manner. He thus adapts animals and plants for his own benefit or pleasure. He may do this methodically, or he may do it unconsciously by preserving the individuals most useful to him at the time, without any thought of altering the breed. It is certain that he can largely influence the character of a breed by selecting, in each successive generation, individual differences so slight as to be quite inappreciable by an uneducated eye. This process of selection has been the great agency in the production of the most distinct and useful domestic breeds. That many of the breeds produced by man have to a large extent the character of natural species, is shown by the inextricable doubts whether very many of them are varieties or aboriginal species.

There is no obvious reason why the principles which have acted so efficiently under domestication should not have acted under nature. In the preservation of favoured individuals and races, during the constantly-recurrent Struggle for Existence, we see the most powerful and ever-acting means of selection. The struggle for existence inevitably follows from the high geometrical ratio of increase which is common to all organic beings. This high rate of increase is proved by calculation, by the effects of a succession of peculiar seasons, and by the results of naturalisation, as explained in the third chapter. More individuals are born than can possibly survive. A grain in the balance will determine which individual shall live and which shall die, -- which variety or species shall increase in number, and which shall decrease, or finally become extinct. As the individuals of the same species come in all respects into the closest competition with each other, the struggle will generally be most severe between them; it will be almost equally severe between the varieties of the same species, and next in severity between the species of the same genus. But the struggle will often be very severe between beings most remote in the scale of nature. The slightest advantage in one being, at any age or during any season, over those with which it comes into competition, or better adaptation in however slight a degree to the surrounding physical conditions, will turn the balance.

With animals having separated sexes there will in most cases be a struggle between the males for possession of the females. The most vigorous individuals, or those which have most successfully struggled with their conditions of life, will generally leave most progeny. But success will often depend on having special weapons or means of defence, or on the charms of the males; and the slightest advantage will lead to victory.

As geology plainly proclaims that each land has undergone great physical changes, we might have expected that organic beings would have varied under nature, in the same way as they generally have varied under the changed conditions of domestication. And if there be any variability under nature, it would be an unaccountable fact if natural selection had not come into play. It has often been asserted, but the assertion is quite incapable of proof, that the amount of variation under nature is a strictly limited quantity. Man, though acting on external characters alone and often capriciously, can produce within a short period a great result by adding up mere individual differences in his domestic productions; and every one admits that there are at least individual differences in species under nature. But, besides such differences, all naturalists have admitted the existence of varieties, which they think sufficiently distinct to be worthy of record in systematic works. No one can draw any clear distinction between individual differences and slight varieties; or between more plainly marked varieties and subspecies, and species. Let it be observed how naturalists differ in the rank which they assign to the many representative forms in Europe and North America.

If then we have under nature variability and a powerful agent always ready to act and select, why should we doubt that variations in any way useful to beings, under their excessively complex relations of life, would be preserved, accumulated, and inherited? Why, if man can by patience select variations most useful to himself, should nature fail in selecting variations useful, under changing conditions of life, to her living products? What limit can be put to this power, acting during long ages and rigidly scrutinising the whole constitution, structure, and habits of each creature, — favouring the good and rejecting the bad? I can see no limit to this power, in slowly and beautifully adapting each form to the most complex relations of life. The theory of natural selection, even if we looked no further than this, seems to me to be in itself probable. I have already recapitulated, as fairly as I could, the opposed difficulties and objections: now let us turn to the special facts and arguments in favour of the theory.

On the view that species are only strongly marked and permanent varieties, and that each species first existed as a variety, we can see why it is that no line of demarcation can be drawn between species, commonly supposed to have been produced by special acts of creation, and varieties which are acknowledged to have been produced by secondary laws. On this same view we can understand how it is that in each region where many species of a genus have been produced, and where they now flourish, these same species should present many varieties; for where the manufactory of species has been active, we might expect, as a general rule, to find it still in action; and this is the case if varieties be incipient species. Moreover, the species of the large genera, which afford the greater number of varieties or incipient species, retain to a certain degree the character of varieties; for they differ from each other by a less amount of difference than do the species of smaller genera. The closely allied species also of the larger genera apparently have restricted ranges, and they are clustered in little groups round other species -- in which respects they resemble varieties. These are strange relations on the view of each species having been independently created, but are intelligible if all species first existed as varieties.

As each species tends by its geometrical ratio of reproduction to increase inordinately in number; and as the modified descendants of each species will be enabled to increase by so much the more as they become more diversified in habits and structure, so as to be enabled to seize on many and widely different places in the economy of nature, there will be a constant tendency in natural selection to preserve the most divergent offspring of any one species. Hence during a long-continued course of modification, the slight differences, characteristic of varieties of the same species, tend to be augmented into the greater differences characteristic of species of the same genus. New and improved varieties will inevitably supplant and exterminate the older, less improved and intermediate varieties; and thus species are rendered to a large extent defined and distinct objects. Dominant species belonging to the larger groups tend to give birth to new and dominant forms; so that each large group tends to become still larger, and at the same time more divergent in character. But as all groups cannot thus succeed in increasing in size, for the world would not hold them, the more dominant groups beat the less dominant. This tendency in the large groups to go on increasing in size and diverging in character, together with the almost inevitable contingency of much extinction, explains the arrangement of all the forms of life, in groups subordinate to groups, all within a few great classes, which we now see everywhere around us, and which has prevailed throughout all time. This grand fact of the grouping of all organic beings seems to me utterly inexplicable on the theory of creation.

As natural selection acts solely by accumulating slight, successive, favourable variations, it can produce no great or sudden modification; it can act only by very short and slow steps. Hence the canon of `Natura non facit saltum,' which every fresh addition to our knowledge tends to make more strictly correct, is on this theory simply intelligible. We can plainly see why nature is prodigal in variety, though niggard in innovation. But why this should be a law of nature if each species has been independently created, no man can explain.

Many other facts are, as it seems to me, explicable on this theory. How strange it is that a bird, under the form of woodpecker, should have been created to prey on insects on the ground; that upland geese, which never or rarely swim, should have been created with webbed feet; that a thrush should have been created to dive and feed on sub-aquatic insects; and that a petrel should have been created with habits and structure fitting it for the life of an auk or grebe! and so on in endless other cases. But on the view of each species constantly trying to increase in number, with natural selection always ready to adapt the slowly varying descendants of each to any unoccupied or ill-occupied place in nature, these facts cease to be strange, or perhaps might even have been anticipated.

As natural selection acts by competition, it adapts the inhabitants of each country only in relation to the degree of perfection of their associates; so that we need feel no surprise at the inhabitants of any one country, although on the ordinary view supposed to have been specially created and adapted for that country, being beaten and supplanted by the naturalised productions from another land. Nor ought we to marvel if all the contrivances in nature be not, as far as we can judge, absolutely perfect; and if some of them be abhorrent to our ideas of fitness. We need not marvel at the sting of the bee causing the bee's own death; at drones being produced in such vast numbers for one single act, and being then slaughtered by their sterile sisters; at the astonishing waste of pollen by our fir-trees; at the instinctive hatred of the queen bee for her own fertile daughters; at ichneumonidae feeding within the live bodies of caterpillars; and at other such cases. The wonder indeed is, on the theory of natural selection, that more cases of the want of absolute perfection have not been observed.

The complex and little known laws governing variation are the same, as far as we can see, with the laws which have governed the production of so-called specific forms. In both cases physical conditions seem to have produced but little direct effect; yet when varieties enter any zone, they occasionally assume some of the characters of the species proper to that zone. In both varieties and species, use and disuse seem to have produced some effect; for it is difficult to resist this conclusion when we look, for instance, at the logger-headed duck, which has wings incapable of flight, in nearly the same condition as in the domestic duck; or when we look at the burrowing tucutucu, which is occasionally blind, and then at certain moles, which are habitually blind and have their eyes covered with skin; or when we look at the blind animals inhabiting the dark caves of America and Europe. In both varieties and species correction of growth seems to have played a most important part, so that when one part has been modified other parts are necessarily modified. In both varieties and species reversions to long-lost characters occur. How inexplicable on the theory of creation is the occasional appearance of stripes on the shoulder and legs of the several species of the horse-genus and in their hybrids! How simply is this fact explained if we believe that these species have descended from a striped progenitor, in the same manner as the several domestic breeds of pigeon have descended from the blue and barred rock-pigeon!

On the ordinary view of each species having been independently created, why should the specific characters, or those by which the species of the same genus differ from each other, be more variable than the generic characters in which they all agree? Why, for instance, should the colour of a flower be more likely to vary in any one species of a genus, if the other species, supposed to have been created independently, have differently coloured flowers, than if all the species of the genus have the same coloured flowers? If species are only well-marked varieties, of which the characters have become in a high degree permanent, we can understand this fact; for they have already varied since they branched off from a common progenitor in certain characters, by which they have come to be specifically distinct from each other; and therefore these same characters would be more likely still to be variable than the generic characters which have been inherited without change for an enormous period. It is inexplicable on the theory of creation why a part developed in a very unusual manner in any one species of a genus, and therefore, as we may naturally infer, of great importance to the species, should be eminently liable to variation; but, on my view, this part has undergone, since the several species branched off from a common progenitor, an unusual amount of variability and modification, and therefore we might expect this part generally to be still variable. But a part may be developed in the most unusual manner, like the wing of a bat, and yet not be more variable than any other structure, if the part be common to many subordinate forms, that is, if it has been inherited for a very long period; for in this case it will have been rendered constant by long-continued natural selection.

Glancing at instincts, marvellous as some are, they offer no greater difficulty than does corporeal structure on the theory of the natural selection of successive, slight, but profitable modifications. We can thus understand why nature moves by graduated steps in endowing different animals of the same class with their several instincts. I have attempted to show how much light the principle of gradation throws on the admirable architectural powers of the hive-bee. Habit no doubt sometimes comes into play in modifying instincts; but it certainly is not indispensable, as we see, in the case of neuter insects, which leave no progeny to inherit the effects of long-continued habit. On the view of all the species of the same genus having descended from a common parent, and having inherited much in common, we can understand how it is that allied species, when placed under considerably different conditions of life, yet should follow nearly the same instincts; why the thrush of South America, for instance, lines her nest with mud like our British species. On the view of instincts having been slowly acquired through natural selection we need not marvel at some instincts being apparently not perfect and liable to mistakes, and at many instincts causing other animals to suffer.

If species be only well-marked and permanent varieties, we can at once see why their crossed offspring should follow the same complex laws in their degrees and kinds of resemblance to their parents, -- in being absorbed into each other by successive crosses, and in other such points, -- as do the crossed offspring of acknowledged varieties. On the other hand, these would be strange facts if species have been independently created, and varieties have been produced by secondary laws.

If we admit that the geological record is imperfect in an extreme degree, then such facts as the record gives, support the theory of descent with modification. New species have come on the stage slowly and at successive intervals; and the amount of change, after equal intervals of time, is widely different in different groups. The extinction of species and of whole groups of species, which has played so conspicuous a part in the history of the organic world, almost inevitably follows on the principle of natural selection; for old forms will be supplanted by new and improved forms. Neither single species nor groups of species reappear when the chain of ordinary generation has once been broken. The gradual diffusion of dominant forms, with the slow modification of their descendants, causes the forms of life, after long intervals of time, to appear as if they had changed simultaneously throughout the world. The fact of the fossil remains of each formation being in some degree intermediate in character between the fossils in the formations above and below, is simply explained by their intermediate position in the chain of descent. The grand fact that all extinct organic beings belong to the same system with recent beings, falling either into the same or into intermediate groups, follows from the living and the extinct being the offspring of common parents. As the groups which have descended from an ancient progenitor have generally diverged in character, the progenitor with its early descendants will often be intermediate in character in comparison with its later descendants; and thus we can see why the more ancient a fossil is, the oftener it stands in some degree intermediate between existing and allied groups. Recent forms are generally looked at as being, in some vague sense, higher than ancient and extinct forms; and they are in so far higher as the later and more improved forms have conquered the older and less improved organic beings in the struggle for life. Lastly, the law of the n='448'> long endurance of allied forms on the same continent, — of marsupials in Australia, of edentata in America, and other such cases, -- is intelligible, for within a confined country, the recent and the extinct will naturally be allied by descent.

Looking to geographical distribution, if we admit that there has been during the long course of ages much migration from one part of the world to another, owing to former climatal and geographical changes and to the many occasional and unknown means of dispersal, then we can understand, on the theory of descent with modification, most of the great leading facts in Distribution. We can see why there should be so striking a parallelism in the distribution of organic beings throughout space, and in their geological succession throughout time; for in both cases the beings have been connected by the bond of ordinary generation, and the means of modification have been the same. We see the full meaning of the wonderful fact, which must have struck every traveller, namely, that on the same continent, under the most diverse conditions, under heat and cold, on mountain and lowland, on deserts and marshes, most of the inhabitants within each great class are plainly related; for they will generally be descendants of the same progenitors and early colonists. On this same principle of former migration, combined in most cases with modification, we can understand, by the aid of the Glacial period, the identity of some few plants, and the close alliance of many others, on the most distant mountains, under the most different climates; and likewise the close alliance of some of the inhabitants of the sea in the northern and southern temperate zones, though separated by the whole intertropical ocean. Although two areas may present the same physical conditions of life, we need feel no surprise at their inhabitants being widely different, if they have been for a long period completely separated from each other; for as the relation of organism to organism is the most important of all relations, and as the two areas will have received colonists from some third source or from each other, at various periods and in different proportions, the course of modification in the two areas will inevitably be different.

On this view of migration, with subsequent modification, we can see why oceanic islands should be inhabited by few species, but of these, that many should be peculiar. We can clearly see why those animals which cannot cross wide spaces of ocean, as frogs and terrestrial mammals, should not inhabit oceanic islands; and why, on the other hand, new and peculiar species of bats, which can traverse the ocean, should so often be found on islands far distant from any continent. Such facts as the presence of peculiar species of bats, and the absence of all other mammals, on oceanic islands, are utterly inexplicable on the theory of independent acts of creation.

The existence of closely allied or representative species in any two areas, implies, on the theory of descent with modification, that the same parents formerly inhabited both areas; and we almost invariably find that wherever many closely allied species inhabit two areas, some identical species common to both still exist. Wherever many closely allied yet distinct species occur, many doubtful forms and varieties of the same species likewise occur. It is a rule of high generality that the inhabitants of each area are related to the inhabitants of the nearest source whence immigrants might have been derived. We see this in nearly all the plants and animals of the Galapagos archipelago, of Juan Fernandez, and of the other American islands being related in the most striking manner to the plants and animals of the neighbouring American mainland; and those of the Cape de Verde archipelago and other African islands to the African mainland. It must be admitted that these facts receive no explanation on the theory of creation.

The fact, as we have seen, that all past and present organic beings constitute one grand natural system, with group subordinate to group, and with extinct groups often falling in between recent groups, is intelligible on the theory of natural selection with its contingencies of extinction and divergence of character. On these same principles we see how it is, that the mutual affinities of the species and genera within each class are so complex and circuitous. We see why certain characters are far more serviceable than others for classification; -- why adaptive characters, though of paramount importance to the being, are of hardly any importance in classification; why characters derived from rudimentary parts, though of no service to the being, are often of high classificatory value; and why embryological characters are the most valuable of all. The real affinities of all organic beings are due to inheritance or community of descent. The natural system is a genealogical arrangement, in which we have to discover the lines of descent by the most permanent characters, however slight their vital importance may be.

The framework of bones being the same in the hand of a man, wing of a bat, fin of the porpoise, and leg of the horse, -- the same number of vertebrae forming the neck of the giraffe and of the elephant, -- and innumerable other such facts, at once explain themselves on the theory of descent with slow and slight successive modifications. The similarity of pattern in the wing and leg of a bat, though used for such different purposes, -- in the jaws and legs of a crab, -- in the petals, stamens, and pistils of a flower, is likewise intelligible on the view of the gradual modification of parts or organs, which were alike in the early progenitor of each class. On the principle of successive variations not always supervening at an early age, and being inherited at a corresponding not early period of life, we can clearly see why the embryos of mammals, birds, reptiles, and fishes should be so closely alike, and should be so unlike the adult forms. We may cease marvelling at the embryo of an air-breathing mammal or bird having branchial slits and arteries running in loops, like those in a fish which has to breathe the air dissolved in water, by the aid of well-developed branchiae.

Disuse, aided sometimes by natural selection, will often tend to reduce an organ, when it has become useless by changed habits or under changed conditions of life; and we can clearly understand on this view the meaning of rudimentary organs. But disuse and selection will generally act on each creature, when it has come to maturity and has to play its full part in the struggle for existence, and will thus have little power of acting on an organ during early life; hence the organ will not be much reduced or rendered rudimentary at this early age. The calf, for instance, has inherited teeth, which never cut through the gums of the upper jaw, from an early progenitor having well-developed teeth; and we may believe, that the teeth in the mature animal were reduced, during successive generations, by disuse or by the tongue and palate having been fitted by natural selection to browse without their aid; whereas in the calf, the teeth have been left untouched by selection or disuse, and on the principle of inheritance at corresponding ages have been inherited from a remote period to the present day. On the view of each organic being and each separate organ having been specially created, how utterly inexplicable it is that parts, like the teeth in the embryonic calf or like the shrivelled wings under the soldered wing-covers of some beetles, should thus so frequently bear the plain stamp of inutility! Nature may be said to have taken pains to reveal, by rudimentary organs and by homologous structures, her scheme of modification, which it seems that we wilfully will not understand.

I have now recapitulated the chief facts and considerations which have thoroughly convinced me that species have changed, and are still slowly changing by the preservation and accumulation of successive slight favourable variations. Why, it may be asked, have all the most eminent living naturalists and geologists rejected this view of the mutability of species? It cannot be asserted that organic beings in a state of nature are subject to no variation; it cannot be proved that the amount of variation in the course of long ages is a limited quantity; no clear distinction has been, or can be, drawn between species and well-marked varieties. It cannot be maintained that species when intercrossed are invariably sterile, and varieties invariably fertile; or that sterility is a special endowment and sign of creation. The belief that species were immutable productions was almost unavoidable as long as the history of the world was thought to be of short duration; and now that we have acquired some idea of the lapse of time, we are too apt to assume, without proof, that the geological record is so perfect that it would have afforded us plain evidence of the mutation of species, if they had undergone mutation.

But the chief cause of our natural unwillingness to admit that one species has given birth to other and distinct species, is that we are always slow in admitting any great change of which we do not see the intermediate steps. The difficulty is the same as that felt by so many geologists, when Lyell first insisted that long lines of inland cliffs had been formed, and great valleys excavated, by the slow action of the coast-waves. The mind cannot possibly grasp the full meaning of the term of a hundred million years; it cannot add up and perceive the full effects of many slight variations, accumulated during an almost infinite number of generations.

Although I am fully convinced of the truth of the views given in this volume under the form of an abstract, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as the `plan of creation,' `unity of design,' &c., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject my theory. A few naturalists, endowed with much flexibility of mind, and who have already begun to doubt on the immutability of species, may be influenced by this volume; but I look with confidence to the future, to young and rising naturalists, who will be able to view both sides of the question with impartiality. Whoever is led to believe that species are mutable will do good service by conscientiously expressing his conviction; for only thus can the load of prejudice by which this subject is overwhelmed be removed.

Several eminent naturalists have of late published their belief that a multitude of reputed species in each genus are not real species; but that other species are real, that is, have been independently created. This seems to me a strange conclusion to arrive at. They admit that a multitude of forms, which till lately they themselves thought were special creations, and which are still thus looked at by the majority of naturalists, and which consequently have every external characteristic feature of true species, -- they admit that these have been produced by variation, but they refuse to extend the same view to other and very slightly different forms. Nevertheless they do not pretend that they can define, or even conjecture, which are the created forms of life, and which are those produced by secondary laws. They admit variation as a vera causa in one case, they arbitrarily reject it in another, without assigning any distinction in the two cases. The day will come when this will be given as a curious illustration of the blindness of preconceived opinion. These authors seem no more startled at a miraculous act of creation than at an ordinary birth. But do they really believe that at innumerable periods in the earth's history certain elemental atoms have been commanded suddenly to flash into living tissues? Do they believe that at each supposed act of creation one individual or many were produced? Were all the infinitely numerous kinds of animals and plants created as eggs or seed, or as full grown? and in the case of mammals, were they created bearing the false marks of nourishment from the mother's womb? Although naturalists very properly demand a full explanation of every difficulty from those who believe in the mutability of species, on their own side they ignore the whole subject of the first appearance of species in what they consider reverent silence.

It may be asked how far I extend the doctrine of the modification of species. The question is difficult to answer, because the more distinct the forms are which we may consider, by so much the arguments fall away in force. But some arguments of the greatest weight extend very far. All the members of whole classes can be connected together by chains of affinities, and all can be classified on the same principle, in groups subordinate to groups. Fossil remains sometimes tend to fill up very wide intervals between existing orders. Organs in a rudimentary condition plainly show that an early progenitor had the organ in a fully developed state; and this in some instances necessarily implies an enormous amount of modification in the descendants. Throughout whole classes various structures are formed on the same pattern, and at an embryonic age the species closely resemble each other. Therefore I cannot doubt that the theory of descent with modification embraces all the members of the same class. I believe that animals have descended from at most only four or five progenitors, and plants from an equal or lesser number.

Analogy would lead me one step further, namely, to the belief that all animals and plants have descended from some one prototype. But analogy may be a deceitful guide. Nevertheless all living things have much in common, in their chemical composition, their germinal vesicles, their cellular structure, and their laws of growth and reproduction. We see this even in so trifling a circumstance as that the same poison often similarly affects plants and animals; or that the poison secreted by the gall-fly produces monstrous growths on the wild rose or oak-tree. Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed.

When the views entertained in this volume on the origin of species, or when analogous views are generally admitted, we can dimly foresee that there will be a considerable revolution in natural history. Systematists will be able to pursue their labours as at present; but they will not be incessantly haunted by the shadowy doubt whether this or that form be in essence a species. This I feel sure, and I speak after experience, will be no slight relief. The endless disputes whether or not some fifty species of British brambles are true species will cease. Systematists will have only to decide (not that this will be easy) whether any form be sufficiently constant and distinct from other forms, to be capable of definition; and if definable, whether the differences be sufficiently important to deserve a specific name. This latter point will become a far more essential consideration than it is at present; for differences, however slight, between any two forms, if not blended by intermediate gradations, are looked at by most naturalists as sufficient to raise both forms to the rank of species. Hereafter we shall be compelled to acknowledge that the only distinction between species and well-marked varieties is, that the latter are known, or believed, to be connected at the present day by intermediate gradations, whereas species were formerly thus connected. Hence, without quite rejecting the consideration of the present existence of intermediate gradations between any two forms, we shall be led to weigh more carefully and to value higher the actual amount of difference between them. It is quite possible that forms now generally acknowledged to be merely varieties may hereafter be thought worthy of specific names, as with the primrose and cowslip; and in this case scientific and common language will come into accordance. In short, we shall have to treat species in the same manner as those naturalists treat genera, who admit that genera are merely artificial combinations made for convenience. This may not be a cheering prospect; but we shall at least be freed from the vain search for the undiscovered and undiscoverable essence of the term species.

The other and more general departments of natural history will rise greatly in interest. The terms used by naturalists of affinity, relationship, community of type, paternity, morphology, adaptive characters, rudimentary and aborted organs, &c., will cease to be metaphorical, and will have a plain signification. When we no longer look at an organic being as a savage looks at a ship, as at something wholly beyond his comprehension; when we regard every production of nature as one which has had a history; when we contemplate every complex structure and instinct as the summing up of many contrivances, each useful to the possessor, nearly in the same way as when we look at any great mechanical invention as the summing up of the labour, the experience, the reason, and even the blunders of numerous workmen; when we thus view each organic being, how far more interesting, I speak from experience, will the study of natural history become!

A grand and almost untrodden field of inquiry will be opened, on the causes and laws of variation, on correlation of growth, on the effects of use and disuse, on the direct action of external conditions, and so forth. The study of domestic productions will rise immensely in value. A new variety raised by man will be a far more important and interesting subject for study than one more species added to the infinitude of already recorded species. Our classifications will come to be, as far as they can be so made, genealogies; and will then truly give what may be called the plan of creation. The rules for classifying will no doubt become simpler when we have a definite object in view. We possess no pedigrees or armorial bearings; and we have to discover and trace the many diverging lines of descent in our natural genealogies, by characters of any kind which have long been inherited. Rudimentary organs will speak infallibly with respect to the nature of long-lost structures. Species and groups of species, which are called aberrant, and which may fancifully be called living fossils, will aid us in forming a picture of the ancient forms of life. Embryology will reveal to us the structure, in some degree obscured, of the prototypes of each great class.

When we can feel assured that all the individuals of the same species, and all the closely allied species of most genera, have within a not very remote period descended from one parent, and have migrated from some one birthplace; and when we better know the many means of migration, then, by the light which geology now throws, and will continue to throw, on former changes of climate and of the level of the land, we shall surely be enabled to trace in an admirable manner the former migrations of the inhabitants of the whole world. Even at present, by comparing the differences of the inhabitants of the sea on the opposite sides of a continent, and the nature of the various inhabitants of that continent in relation to their apparent means of immigration, some light can be thrown on ancient geography.

The noble science of Geology loses glory from the extreme imperfection of the record. The crust of the earth with its embedded remains must not be looked at as a well-filled museum, but as a poor collection made at hazard and at rare intervals. The accumulation of each great fossiliferous formation will be recognised as having depended on an unusual concurrence of circumstances, and the blank intervals between the successive stages as having been of vast duration. But we shall be able to gauge with some security the duration of these intervals by a comparison of the preceding and succeeding organic forms. We must be cautious in attempting to correlate as strictly contemporaneous two formations, which include few identical species, by the general succession of their forms of life. As species are produced and exterminated by slowly acting and still existing causes, and not by miraculous acts of creation and by catastrophes; and as the most important of all causes of organic change is one which is almost independent of altered and perhaps suddenly altered physical conditions, namely, the mutual relation of organism to organism, -- the improvement of one being entailing the improvement or the extermination of others; it follows, that the amount of organic change in the fossils of consecutive formations probably serves as a fair measure of the lapse of actual time. A number of species, however, keeping in a body might remain for a long period unchanged, whilst within this same period, several of these species, by migrating into new countries and coming into competition with foreign associates, might become modified; so that we must not overrate the accuracy of organic change as a measure of time. During early periods of the earth's history, when the forms of life were probably fewer and simpler, the rate of change was probably slower; and at the first dawn of life, when very few forms of the simplest structure existed, the rate of change may have been slow in an extreme degree. The whole history of the world, as at present known, although of a length quite incomprehensible by us, will hereafter be recognised as a mere fragment of time, compared with the ages which have elapsed since the first creature, the progenitor of innumerable extinct and living descendants, was created.

In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history.

Authors of the highest eminence seem to be fully satisfied with the view that each species has been independently created. To my mind it accords better with what we know of the laws impressed on matter by the Creator, that the production and extinction of the past and present inhabitants of the world should have been due to secondary causes, like those determining the birth and death of the individual. When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Silurian system was deposited, they seem to me to become ennobled. Judging from the past, we may safely infer that not one living species will transmit its unaltered likeness to a distant futurity. And of the species now living very few will transmit progeny of any kind to a far distant futurity; for the manner in which all organic beings are grouped, shows that the greater number of species of each genus, and all the species of many genera, have left no descendants, but have become utterly extinct. We can so far take a prophetic glance into futurity as to foretel that it will be the common and widely-spread species, belonging to the larger and dominant groups, which will ultimately prevail and procreate new and dominant species. As all the living forms of life are the lineal descendants of those which lived long before the Silurian epoch, we may feel certain that the ordinary succession by generation has never once been broken, and that no cataclysm has desolated the whole world. Hence we may look with some confidence to a secure future of equally inappreciable length. And as natural selection works solely by and for the good of each being, all corporeal and mental endowments will tend to progress towards perfection.

It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with Reproduction; inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the external conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less-improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved. THE share which worms have taken in the formation of the layer of
vegetable mould, which covers the whole surface of the land in every
moderately humid country, is the subject of the present volume.  This
mould is generally of a blackish colour and a few inches in thickness.
In different districts it differs but little in appearance, although it
may rest on various subsoils.  The uniform fineness of the particles of
which it is composed is one of its chief characteristic features; and
this may be well observed in any gravelly country, where a
recently-ploughed field immediately adjoins one which has long remained
undisturbed for pasture, and where the vegetable mould is exposed on the
sides of a ditch or hole.  The subject may appear an insignificant one,
but we shall see that it possesses some interest; and the maxim “de
minimis non curat lex,” does not apply to science.  Even Élie de
Beaumont, who generally undervalues small agencies and their accumulated
effects, remarks: {2} “La couche très-mince de la terre végétale est un
monument d’une haute antiquité, et, par le fait de sa permanence, un
objet digne d’occuper le géologue, et capable de lui fournir des
remarques intéressantes.”  Although the superficial layer of vegetable
mould as a whole no doubt is of the highest antiquity, yet in regard to
its permanence, we shall hereafter see reason to believe that its
component particles are in most cases removed at not a very slow rate,
and are replaced by others due to the disintegration of the underlying
materials.

As I was led to keep in my study during many months worms in pots filled
with earth, I became interested in them, and wished to learn how far they
acted consciously, and how much mental power they displayed.  I was the
more desirous to learn something on this head, as few observations of
this kind have been made, as far as I know, on animals so low in the
scale of organization and so poorly provided with sense-organs, as are
earth-worms.

In the year 1837, a short paper was read by me before the Geological
Society of London, {3} “On the Formation of Mould,” in which it was shown
that small fragments of burnt marl, cinders, &c., which had been thickly
strewed over the surface of several meadows, were found after a few years
lying at the depth of some inches beneath the turf, but still forming a
layer.  This apparent sinking of superficial bodies is due, as was first
suggested to me by Mr. Wedgwood of Maer Hall in Staffordshire, to the
large quantity of fine earth continually brought up to the surface by
worms in the form of castings.  These castings are sooner or later spread
out and cover up any object left on the surface.  I was thus led to
conclude that all the vegetable mould over the whole country has passed
many times through, and will again pass many times through, the
intestinal canals of worms.  Hence the term “animal mould” would be in
some respects more appropriate than that commonly used of “vegetable
mould.”

Ten years after the publication of my paper, M. D’Archiac, evidently
influenced by the doctrines of Élie de Beaumont, wrote about my
“singulière théorie,” and objected that it could apply only to “les
prairies basses et humides;” and that “les terres labourées, les bois,
les prairies élevées, n’apportent aucune preuve à l’appui de cette
manière de voir.” {4a}  But M. D’Archiac must have thus argued from inner
consciousness and not from observation, for worms abound to an
extraordinary degree in kitchen gardens where the soil is continually
worked, though in such loose soil they generally deposit their castings
in any open cavities or within their old burrows instead of on the
surface.  Hensen estimates that there are about twice as many worms in
gardens as in corn-fields. {4b}  With respect to “prairies élevées,” I do
not know how it may be in France, but nowhere in England have I seen the
ground so thickly covered with castings as on commons, at a height of
several hundred feet above the sea.  In woods again, if the loose leaves
in autumn are removed, the whole surface will be found strewed with
castings.  Dr. King, the superintendent of the Botanic Garden in
Calcutta, to whose kindness I am indebted for many observations on
earth-worms, informs me that he found, near Nancy in France, the bottom
of the State forests covered over many acres with a spongy layer,
composed of dead leaves and innumerable worm-castings.  He there heard
the Professor of “Aménagement des Forêts” lecturing to his pupils, and
pointing out this case as a “beautiful example of the natural cultivation
of the soil; for year after year the thrown-up castings cover the dead
leaves; the result being a rich humus of great thickness.”

In the year 1869, Mr. Fish {5} rejected my conclusions with respect to
the part which worms have played in the formation of vegetable mould,
merely on account of their assumed incapacity to do so much work.  He
remarks that “considering their weakness and their size, the work they
are represented to have accomplished is stupendous.”  Here we have an
instance of that inability to sum up the effects of a continually
recurrent cause, which has often retarded the progress of science, as
formerly in the case of geology, and more recently in that of the
principle of evolution.

Although these several objections seemed to me to have no weight, yet I
resolved to make more observations of the same kind as those published,
and to attack the problem on another side; namely, to weigh all the
castings thrown up within a given time in a measured space, instead of
ascertaining the rate at which objects left on the surface were buried by
worms.  But some of my observations have been rendered almost superfluous
by an admirable paper by Hensen, already alluded to, which appeared in
1877. {6}  Before entering on details with respect to the castings, it
will be advisable to give some account of the habits of worms from my own
observations and from those of other naturalists.

[FIRST EDITION,
            _October_ 10_th_, 1881.]




CHAPTER I.
HABITS OF WORMS.


Nature of the sites inhabited—Can live long under water—Nocturnal—Wander
about at night—Often lie close to the mouths of their burrows, and are
thus destroyed in large numbers by birds—Structure—Do not possess eyes,
but can distinguish between light and darkness—Retreat rapidly when
brightly illuminated, not by a reflex action—Power of attention—Sensitive
to heat and cold—Completely deaf—Sensitive to vibrations and to
touch—Feeble power of smell—Taste—Mental qualities—Nature of
food—Omnivorous—Digestion—Leaves before being swallowed, moistened with a
fluid of the nature of the pancreatic secretion—Extra-stomachal
digestion—Calciferous glands, structure of—Calcareous concretions formed
in the anterior pair of glands—The calcareous matter primarily an
excretion, but secondarily serves to neutralise the acids generated
during the digestive process.

EARTH-WORMS are distributed throughout the world under the form of a few
genera, which externally are closely similar to one another.  The British
species of Lumbricus have never been carefully monographed; but we may
judge of their probable number from those inhabiting neighbouring
countries.  In Scandinavia there are eight species, according to Eisen;
{8a} but two of these rarely burrow in the ground, and one inhabits very
wet places or even lives under the water.  We are here concerned only
with the kinds which bring up earth to the surface in the form of
castings.  Hoffmeister says that the species in Germany are not well
known, but gives the same number as Eisen, together with some strongly
marked varieties. {8b}

Earth-worms abound in England in many different stations.  Their castings
may be seen in extraordinary numbers on commons and chalk-downs, so as
almost to cover the whole surface, where the soil is poor and the grass
short and thin.  But they are almost or quite as numerous in some of the
London parks, where the grass grows well and the soil appears rich.  Even
on the same field worms are much more frequent in some places than in
others, without any visible difference in the nature of the soil.  They
abound in paved court-yards close to houses; and an instance will be
given in which they had burrowed through the floor of a very damp cellar.
I have seen worms in black peat in a boggy field; but they are extremely
rare, or quite absent in the drier, brown, fibrous peat, which is so much
valued by gardeners.  On dry, sandy or gravelly tracks, where heath with
some gorse, ferns, coarse grass, moss and lichens alone grow, hardly any
worms can be found.  But in many parts of England, wherever a path
crosses a heath, its surface becomes covered with a fine short sward.
Whether this change of vegetation is due to the taller plants being
killed by the occasional trampling of man and animals, or to the soil
being occasionally manured by the droppings from animals, I do not know.
{9b}  On such grassy paths worm-castings may often be seen.  On a heath
in Surrey, which was carefully examined, there were only a few castings
on these paths, where they were much inclined; but on the more level
parts, where a bed of fine earth had been washed down from the steeper
parts and had accumulated to a thickness of a few inches, worm-castings
abounded.  These spots seemed to be overstocked with worms, so that they
had been compelled to spread to a distance of a few feet from the grassy
paths, and here their castings had been thrown up among the heath; but
beyond this limit, not a single casting could be found.  A layer, though
a thin one, of fine earth, which probably long retains some moisture, is
in all cases, as I believe, necessary for their existence; and the mere
compression of the soil appears to be in some degree favourable to them,
for they often abound in old gravel walks, and in foot-paths across
fields.

Beneath large trees few castings can be found during certain seasons of
the year, and this is apparently due to the moisture having been sucked
out of the ground by the innumerable roots of the trees; for such places
may be seen covered with castings after the heavy autumnal rains.
Although most coppices and woods support many worms, yet in a forest of
tall and ancient beech-trees in Knole Park, where the ground beneath was
bare of all vegetation, not a single casting could be found over wide
spaces, even during the autumn.  Nevertheless, castings were abundant on
some grass-covered glades and indentations which penetrated this forest.
On the mountains of North Wales and on the Alps, worms, as I have been
informed, are in most places rare; and this may perhaps be due to the
close proximity of the subjacent rocks, into which worms cannot burrow
during the winter so as to escape being frozen.  Dr. McIntosh, however,
found worm-castings at a height of 1500 feet on Schiehallion in Scotland.
They are numerous on some hills near Turin at from 2000 to 3000 feet
above the sea, and at a great altitude on the Nilgiri Mountains in South
India and on the Himalaya.

Earth-worms must be considered as terrestrial animals, though they are
still in one sense semi-aquatic, like the other members of the great
class of annelids to which they belong.  M. Perrier found that their
exposure to the dry air of a room for only a single night was fatal to
them.  On the other hand he kept several large worms alive for nearly
four months, completely submerged in water. {11}  During the summer when
the ground is dry, they penetrate to a considerable depth and cease to
work, as they do during the winter when the ground is frozen.  Worms are
nocturnal in their habits, and at night may be seen crawling about in
large numbers, but usually with their tails still inserted in their
burrows.  By the expansion of this part of their bodies, and with the
help of the short, slightly reflexed bristles, with which their bodies
are armed, they hold so fast that they can seldom be dragged out of the
ground without being torn into pieces. {12}  During the day they remain
in their burrows, except at the pairing season, when those which inhabit
adjoining burrows expose the greater part of their bodies for an hour or
two in the early morning.  Sick individuals, which are generally affected
by the parasitic larvæ of a fly, must also be excepted, as they wander
about during the day and die on the surface.  After heavy rain succeeding
dry weather, an astonishing number of dead worms may sometimes be seen
lying on the ground.  Mr. Galton informs me that on one such occasion
(March, 1881), the dead worms averaged one for every two and a half paces
in length on a walk in Hyde Park, four paces in width.  He counted no
less than 45 dead worms in one place in a length of sixteen paces.  From
the facts above given, it is not probable that these worms could have
been drowned, and if they had been drowned they would have perished in
their burrows.  I believe that they were already sick, and that their
deaths were merely hastened by the ground being flooded.

It has often been said that under ordinary circumstances healthy worms
never, or very rarely, completely leave their burrows at night; but this
is an error, as White of Selborne long ago knew.  In the morning, after
there has been heavy rain, the film of mud or of very fine sand over
gravel-walks is often plainly marked with their tracks.  I have noticed
this from August to May, both months included, and it probably occurs
during the two remaining months of the year when they are wet.  On these
occasions, very few dead worms could anywhere be seen.  On January 31,
1881, after a long-continued and unusually severe frost with much snow,
as soon as a thaw set in, the walks were marked with innumerable tracks.
On one occasion, five tracks were counted crossing a space of only an
inch square.  They could sometimes be traced either to or from the mouths
of the burrows in the gravel-walks, for distances between 2 or 3 up to 15
yards.  I have never seen two tracks leading to the same burrow; nor is
it likely, from what we shall presently see of their sense-organs, that a
worm could find its way back to its burrow after having once left it.
They apparently leave their burrows on a voyage of discovery, and thus
they find new sites to inhabit.

Morren states {14} that worms often lie for hours almost motionless close
beneath the mouths of their burrows.  I have occasionally noticed the
same fact with worms kept in pots in the house; so that by looking down
into their burrows, their heads could just be seen.  If the ejected earth
or rubbish over the burrows be suddenly removed, the end of the worm’s
body may very often be seen rapidly retreating.  This habit of lying near
the surface leads to their destruction to an immense extent.  Every
morning during certain seasons of the year, the thrushes and blackbirds
on all the lawns throughout the country draw out of their holes an
astonishing number of worms, and this they could not do, unless they lay
close to the surface.  It is not probable that worms behave in this
manner for the sake of breathing fresh air, for we have seen that they
can live for a long time under water.  I believe that they lie near the
surface for the sake of warmth, especially in the morning; and we shall
hereafter find that they often coat the mouths of their burrows with
leaves, apparently to prevent their bodies from coming into close contact
with the cold damp earth.  It is said that they completely close their
burrows during the winter.

_Structure_.—A few remarks must be made on this subject.  The body of a
large worm consists of from 100 to 200 almost cylindrical rings or
segments, each furnished with minute bristles.  The muscular system is
well developed.  Worms can crawl backwards as well as forwards, and by
the aid of their affixed tails can retreat with extraordinary rapidity
into their burrows.  The mouth is situated at the anterior end of the
body, and is provided with a little projection (lobe or lip, as it has
been variously called) which is used for prehension.  Internally, behind
the mouth, there is a strong pharynx, shown in the accompanying diagram
(Fig. 1) which is pushed forwards when the animal eats, and this part
corresponds, according to Perrier, with the protrudable trunk or
proboscis of other annelids.  The pharynx leads into the œsophagus, on
each side of which in the lower part there are three pairs of large
glands, which secrete a surprising amount of carbonate of lime.  These
calciferous glands are highly remarkable, for nothing like them is known
in any other animal.  Their use will be discussed when we treat of the
digestive process.  In most of the species, the œsophagus is enlarged
into a crop in front of the gizzard.  This latter organ is lined with a
smooth thick chitinous membrane, and is surrounded by weak longitudinal,
but powerful transverse muscles.  Perrier saw these muscles in energetic
action; and, as he remarks, the trituration of the food must be chiefly
effected by this organ, for worms possess no jaws or teeth of any kind.
Grains of sand and small stones, from the 1/20 to a little more than the
1/10 inch in diameter, may generally be found in their gizzards and
intestines.  As it is certain that worms swallow many little stones,
independently of those swallowed while excavating their burrows, it is
probable that they serve, like mill-stones, to triturate their food.  The
gizzard opens into the intestine, which runs in a straight course to the
vent at the posterior end of the body.  The intestine presents a
remarkable structure, the typhlosolis, or, as the old anatomists called
it, an intestine within an intestine; and Claparède {17} has shown that
this consists of a deep longitudinal involution of the walls of the
intestine, by which means an extensive absorbent surface is gained.

[Picture: Fig. 1: Diagram of the alimentary canal of an earth-worm.  Fig.
                  2: Tower-like casting from near Nice]

The circulatory system is well developed.  Worms breathe by their skin,
as they do not possess any special respiratory organs.  The two sexes are
united in the same individual, but two individuals pair together.  The
nervous system is fairly well developed; and the two almost confluent
cerebral ganglia are situated very near to the anterior end of the body.

_Senses_.—Worms are destitute of eyes, and at first I thought that they
were quite insensible to light; for those kept in confinement were
repeatedly observed by the aid of a candle, and others out of doors by
the aid of a lantern, yet they were rarely alarmed, although extremely
timid animals.  Other persons have found no difficulty in observing worms
at night by the same means. {18a}

Hoffmeister, however, states {18b} that worms, with the exception of a
few individuals, are extremely sensitive to light; but he admits that in
most cases a certain time is requisite for its action.  These statements
led me to watch on many successive nights worms kept in pots, which were
protected from currents of air by means of glass plates.  The pots were
approached very gently, in order that no vibration of the floor should be
caused.  When under these circumstances worms were illuminated by a
bull’s-eye lantern having slides of dark red and blue glass, which
intercepted so much light that they could be seen only with some
difficulty, they were not at all affected by this amount of light,
however long they were exposed to it.  The light, as far as I could
judge, was brighter than that from the full moon.  Its colour apparently
made no difference in the result.  When they were illuminated by a
candle, or even by a bright paraffin lamp, they were not usually affected
at first.  Nor were they when the light was alternately admitted and shut
off.  Sometimes, however, they behaved very differently, for as soon as
the light fell on them, they withdrew into their burrows with almost
instantaneous rapidity.  This occurred perhaps once out of a dozen times.
When they did not withdraw instantly, they often raised the anterior
tapering ends of their bodies from the ground, as if their attention was
aroused or as if surprise was felt; or they moved their bodies from side
to side as if feeling for some object.  They appeared distressed by the
light; but I doubt whether this was really the case, for on two occasions
after withdrawing slowly, they remained for a long time with their
anterior extremities protruding a little from the mouths of their
burrows, in which position they were ready for instant and complete
withdrawal.

When the light from a candle was concentrated by means of a large lens on
the anterior extremity, they generally withdrew instantly; but this
concentrated light failed to act perhaps once out of half a dozen trials.
The light was on one occasion concentrated on a worm lying beneath water
in a saucer, and it instantly withdrew into its burrow.  In all cases the
duration of the light, unless extremely feeble, made a great difference
in the result; for worms left exposed before a paraffin lamp or a candle
invariably retreated into their burrows within from five to fifteen
minutes; and if in the evening the pots were illuminated before the worms
had come out of their burrows, they failed to appear.

From the foregoing facts it is evident that light affects worms by its
intensity and by its duration.  It is only the anterior extremity of the
body, where the cerebral ganglia lie, which is affected by light, as
Hoffmeister asserts, and as I observed on many occasions.  If this part
is shaded, other parts of the body may be fully illuminated, and no
effect will be produced.  As these animals have no eyes, we must suppose
that the light passes through their skins, and in some manner excites
their cerebral ganglia.  It appeared at first probable that the different
manner in which they were affected on different occasions might be
explained, either by the degree of extension of their skin and its
consequent transparency, or by some particular incident of the light; but
I could discover no such relation.  One thing was manifest, namely, that
when worms were employed in dragging leaves into their burrows or in
eating them, and even during the short intervals whilst they rested from
their work, they either did not perceive the light or were regardless of
it; and this occurred even when the light was concentrated on them
through a large lens.  So, again, whilst they are paired, they will
remain for an hour or two out of their burrows, fully exposed to the
morning light; but it appears from what Hoffmeister says that a light
will occasionally cause paired individuals to separate.

When a worm is suddenly illuminated and dashes like a rabbit into its
burrow—to use the expression employed by a friend—we are at first led to
look at the action as a reflex one.  The irritation of the cerebral
ganglia appears to cause certain muscles to contract in an inevitable
manner, independently of the will or consciousness of the animal, as if
it were an automaton.  But the different effect which a light produced on
different occasions, and especially the fact that a worm when in any way
employed and in the intervals of such employment, whatever set of muscles
and ganglia may then have been brought into play, is often regardless of
light, are opposed to the view of the sudden withdrawal being a simple
reflex action.  With the higher animals, when close attention to some
object leads to the disregard of the impressions which other objects must
be producing on them, we attribute this to their attention being then
absorbed; and attention implies the presence of a mind.  Every sportsman
knows that he can approach animals whilst they are grazing, fighting or
courting, much more easily than at other times.  The state, also, of the
nervous system of the higher animals differs much at different times, for
instance, a horse is much more readily startled at one time than at
another.  The comparison here implied between the actions of one of the
higher animals and of one so low in the scale as an earth-worm, may
appear far-fetched; for we thus attribute to the worm attention and some
mental power, nevertheless I can see no reason to doubt the justice of
the comparison.

Although worms cannot be said to possess the power of vision, their
sensitiveness to light enables them to distinguish between day and night;
and they thus escape extreme danger from the many diurnal animals which
prey on them.  Their withdrawal into their burrows during the day
appears, however, to have become an habitual action; for worms kept in
pots covered by glass plates, over which sheets of black paper were
spread, and placed before a north-east window, remained during the
day-time in their burrows and came out every night; and they continued
thus to act for a week.  No doubt a little light may have entered between
the sheets of glass and the blackened paper; but we know from the trials
with coloured glass, that worms are indifferent to a small amount of
light.

Worms appear to be less sensitive to moderate radiant heat than to a
bright light.  I judge of this from having held at different times a
poker heated to dull redness near some worms, at a distance which caused
a very sensible degree of warmth in my hand.  One of them took no notice;
a second withdrew into its burrow, but not quickly; the third and fourth
much more quickly, and the fifth as quickly as possible.  The light from
a candle, concentrated by a lens and passing through a sheet of glass
which would intercept most of the heat-rays, generally caused a much more
rapid retreat than did the heated poker.  Worms are sensitive to a low
temperature, as may be inferred from their not coming out of their
burrows during a frost.

Worms do not possess any sense of hearing.  They took not the least
notice of the shrill notes from a metal whistle, which was repeatedly
sounded near them; nor did they of the deepest and loudest tones of a
bassoon.  They were indifferent to shouts, if care was taken that the
breath did not strike them.  When placed on a table close to the keys of
a piano, which was played as loudly as possible, they remained perfectly
quiet.

Although they are indifferent to undulations in the air audible by us,
they are extremely sensitive to vibrations in any solid object.  When the
pots containing two worms which had remained quite indifferent to the
sound of the piano, were placed on this instrument, and the note C in the
bass clef was struck, both instantly retreated into their burrows.  After
a time they emerged, and when G above the line in the treble clef was
struck they again retreated.  Under similar circumstances on another
night one worm dashed into its burrow on a very high note being struck
only once, and the other worm when C in the treble clef was struck.  On
these occasions the worms were not touching the sides of the pots, which
stood in saucers; so that the vibrations, before reaching their bodies,
had to pass from the sounding board of the piano, through the saucer, the
bottom of the pot and the damp, not very compact earth on which they lay
with their tails in their burrows.  They often showed their sensitiveness
when the pot in which they lived, or the table on which the pot stood,
was accidentally and lightly struck; but they appeared less sensitive to
such jars than to the vibrations of the piano; and their sensitiveness to
jars varied much at different times.

It has often been said that if the ground is beaten or otherwise made to
tremble, worms believe that they are pursued by a mole and leave their
burrows.  From one account that I have received, I have no doubt that
this is often the case; but a gentleman informs me that he lately saw
eight or ten worms leave their burrows and crawl about the grass on some
boggy land on which two men had just trampled while setting a trap; and
this occurred in a part of Ireland where there were no moles.  I have
been assured by a Volunteer that he has often seen many large earth-worms
crawling quickly about the grass, a few minutes after his company had
fired a volley with blank cartridges.  The Peewit (_Tringa vanellus_,
Linn.) seems to know instinctively that worms will emerge if the ground
is made to tremble; for Bishop Stanley states (as I hear from Mr.
Moorhouse) that a young peewit kept in confinement used to stand on one
leg and beat the turf with the other leg until the worms crawled out of
their burrows, when they were instantly devoured.  Nevertheless, worms do
not invariably leave their burrows when the ground is made to tremble, as
I know by having beaten it with a spade, but perhaps it was beaten too
violently.

The whole body of a worm is sensitive to contact.  A slight puff of air
from the mouth causes an instant retreat.  The glass plates placed over
the pots did not fit closely, and blowing through the very narrow chinks
thus left, often sufficed to cause a rapid retreat.  They sometimes
perceived the eddies in the air caused by quickly removing the glass
plates.  When a worm first comes out of its burrow, it generally moves
the much extended anterior extremity of its body from side to side in all
directions, apparently as an organ of touch; and there is some reason to
believe, as we shall see in the next chapter, that they are thus enabled
to gain a general notion of the form of an object.  Of all their senses
that of touch, including in this term the perception of a vibration,
seems much the most highly developed.

In worms the sense of smell apparently is confined to the perception of
certain odours, and is feeble.  They were quite indifferent to my breath,
as long as I breathed on them very gently.  This was tried, because it
appeared possible that they might thus be warned of the approach of an
enemy.  They exhibited the same indifference to my breath whilst I chewed
some tobacco, and while a pellet of cotton-wool with a few drops of
millefleurs perfume or of acetic acid was kept in my mouth.  Pellets of
cotton-wool soaked in tobacco juice, in millefleurs perfume, and in
paraffin, were held with pincers and were waved about within two or three
inches of several worms, but they took no notice.  On one or two
occasions, however, when acetic acid had been placed on the pellets, the
worms appeared a little uneasy, and this was probably due to the
irritation of their skins.  The perception of such unnatural odours would
be of no service to worms; and as such timid creatures would almost
certainly exhibit some signs of any new impression, we may conclude that
they did not perceive these odours.

The result was different when cabbage-leaves and pieces of onion were
employed, both of which are devoured with much relish by worms.  Small
square pieces of fresh and half-decayed cabbage-leaves and of onion bulbs
were on nine occasions buried in my pots, beneath about ¼ of an inch of
common garden soil; and they were always discovered by the worms.  One
bit of cabbage was discovered and removed in the course of two hours;
three were removed by the next morning, that is, after a single night;
two others after two nights; and the seventh bit after three nights.  Two
pieces of onion were discovered and removed after three nights.  Bits of
fresh raw meat, of which worms are very fond, were buried, and were not
discovered within forty-eight hours, during which time they had not
become putrid.  The earth above the various buried objects was generally
pressed down only slightly, so as not to prevent the emission of any
odour.  On two occasions, however, the surface was well watered, and was
thus rendered somewhat compact.  After the bits of cabbage and onion had
been removed, I looked beneath them to see whether the worms had
accidentally come up from below, but there was no sign of a burrow; and
twice the buried objects were laid on pieces of tin-foil which were not
in the least displaced.  It is of course possible that the worms whilst
moving about on the surface of the ground, with their tails affixed
within their burrows, may have poked their heads into the places where
the above objects were buried; but I have never seen worms acting in this
manner.  Some pieces of cabbage-leaf and of onion were twice buried
beneath very fine ferruginous sand, which was slightly pressed down and
well watered, so as to be rendered very compact, and these pieces were
never discovered.  On a third occasion the same kind of sand was neither
pressed down nor watered, and the pieces of cabbage were discovered and
removed after the second night.  These several facts indicate that worms
possess some power of smell; and that they discover by this means
odoriferous and much-coveted kinds of food.

It may be presumed that all animals which feed on various substances
possess the sense of taste, and this is certainly the case with worms.
Cabbage-leaves are much liked by worms; and it appears that they can
distinguish between different varieties; but this may perhaps be owing to
differences in their texture.  On eleven occasions pieces of the fresh
leaves of a common green variety and of the red variety used for pickling
were given them, and they preferred the green, the red being either
wholly neglected or much less gnawed.  On two other occasions, however,
they seemed to prefer the red.  Half-decayed leaves of the red variety
and fresh leaves of the green were attacked about equally.  When leaves
of the cabbage, horse-radish (a favourite food) and of the onion were
given together, the latter were always, and manifestly preferred.  Leaves
of the cabbage, lime-tree, Ampelopsis, parsnip (Pastinaca), and celery
(Apium) were likewise given together; and those of the celery were first
eaten.  But when leaves of cabbage, turnip, beet, celery, wild cherry and
carrots were given together, the two latter kinds, especially those of
the carrot, were preferred to all the others, including those of celery.
It was also manifest after many trials that wild cherry leaves were
greatly preferred to those of the lime-tree and hazel (Corylus).
According to Mr. Bridgman the half-decayed leaves of _Phlox verna_ are
particularly liked by worms. {31}

Pieces of the leaves of cabbage, turnip, horse-radish and onion were left
on the pots during 22 days, and were all attacked and had to be renewed;
but during the whole of this time leaves of an Artemisia and of the
culinary sage, thyme and mint, mingled with the above leaves, were quite
neglected excepting those of the mint, which were occasionally and very
slightly nibbled.  These latter four kinds of leaves do not differ in
texture in a manner which could make them disagreeable to worms; they all
have a strong taste, but so have the four first mentioned kinds of
leaves; and the wide difference in the result must be attributed to a
preference by the worms for one taste over another.

_Mental Qualities_.—There is little to be said on this head.  We have
seen that worms are timid.  It may be doubted whether they suffer as much
pain when injured, as they seem to express by their contortions.  Judging
by their eagerness for certain kinds of food, they must enjoy the
pleasure of eating.  Their sexual passion is strong enough to overcome
for a time their dread of light.  They perhaps have a trace of social
feeling, for they are not disturbed by crawling over each other’s bodies,
and they sometimes lie in contact.  According to Hoffmeister they pass
the winter either singly or rolled up with others into a ball at the
bottom of their burrows. {32}  Although worms are so remarkably deficient
in the several sense-organs, this does not necessarily preclude
intelligence, as we know from such cases as those of Laura Bridgman; and
we have seen that when their attention is engaged, they neglect
impressions to which they would otherwise have attended; and attention
indicates the presence of a mind of some kind.  They are also much more
easily excited at certain times than at others.  They perform a few
actions instinctively, that is, all the individuals, including the young,
perform such actions in nearly the same fashion.  This is shown by the
manner in which the species of Perichæta eject their castings, so as to
construct towers; also by the manner in which the burrows of the common
earth-worm are smoothly lined with fine earth and often with little
stones, and the mouths of their burrows with leaves.  One of their
strongest instincts is the plugging up the mouths of their burrows with
various objects; and very young worms act in this manner.  But some
degree of intelligence appears, as we shall see in the next chapter, to
be exhibited in this work,—a result which has surprised me more than
anything else in regard to worms.

_Food and Digestion_.—Worms are omnivorous.  They swallow an enormous
quantity of earth, out of which they extract any digestible matter which
it may contain; but to this subject I must recur.  They also consume a
large number of half-decayed leaves of all kinds, excepting a few which
have an unpleasant taste or are too tough for them; likewise petioles,
peduncles, and decayed flowers.  But they will also consume fresh leaves,
as I have found by repeated trials.  According to Morren {33} they will
eat particles of sugar and liquorice; and the worms which I kept drew
many bits of dry starch into their burrows, and a large bit had its
angles well rounded by the fluid poured out of their mouths.  But as they
often drag particles of soft stone, such as of chalk, into their burrows,
I feel some doubt whether the starch was used as food.  Pieces of raw and
roasted meat were fixed several times by long pins to the surface of the
soil in my pots, and night after night the worms could be seen tugging at
them, with the edges of the pieces engulfed in their mouths, so that much
was consumed.  Raw fat seems to be preferred even to raw meat or to any
other substance which was given them, and much was consumed.  They are
cannibals, for the two halves of a dead worm placed in two of the pots
were dragged into the burrows and gnawed; but as far as I could judge,
they prefer fresh to putrid meat, and in so far I differ from
Hoffmeister.

Léon Fredericq states {34} that the digestive fluid of worms is of the
same nature as the pancreatic secretion of the higher animals; and this
conclusion agrees perfectly with the kinds of food which worms consume.
Pancreatic juice emulsifies fat, and we have just seen how greedily worms
devour fat; it dissolves fibrin, and worms eat raw meat; it converts
starch into grape-sugar with wonderful rapidity, and we shall presently
show that the digestive fluid of worms acts on starch. {35a}  But they
live chiefly on half-decayed leaves; and these would be useless to them
unless they could digest the cellulose forming the cell-walls; for it is
well known that all other nutritious substances are almost completely
withdrawn from leaves, shortly before they fall off.  It has, however,
now been ascertained that some forms of cellulose, though very little or
not at all attacked by the gastric secretion of the higher animals, are
acted on by that from the pancreas. {35b}

The half-decayed or fresh leaves which worms intend to devour, are
dragged into the mouths of their burrows to a depth of from one to three
inches, and are then moistened with a secreted fluid.  It has been
assumed that this fluid serves to hasten their decay; but a large number
of leaves were twice pulled out of the burrows of worms and kept for many
weeks in a very moist atmosphere under a bell-glass in my study; and the
parts which had been moistened by the worms did not decay more quickly in
any plain manner than the other parts.  When fresh leaves were given in
the evening to worms kept in confinement and examined early on the next
morning, therefore not many hours after they had been dragged into the
burrows, the fluid with which they were moistened, when tested with
neutral litmus paper, showed an alkaline reaction.  This was repeatedly
found to be the case with celery, cabbage and turnip leaves.  Parts of
the same leaves which had not been moistened by the worms, were pounded
with a few drops of distilled water, and the juice thus extracted was not
alkaline.  Some leaves, however, which had been drawn into burrows out of
doors, at an unknown antecedent period, were tried, and though still
moist, they rarely exhibited even a trace of alkaline reaction.

The fluid, with which the leaves are bathed, acts on them whilst they are
fresh or nearly fresh, in a remarkable manner; for it quickly kills and
discolours them.  Thus the ends of a fresh carrot-leaf, which had been
dragged into a burrow, were found after twelve hours of a dark brown
tint.  Leaves of celery, turnip, maple, elm, lime, thin leaves of ivy,
and, occasionally those of the cabbage were similarly acted on.  The end
of a leaf of _Triticum repens_, still attached to a growing plant, had
been drawn into a burrow, and this part was dark brown and dead, whilst
the rest of the leaf was fresh and green.  Several leaves of lime and elm
removed from burrows out of doors were found affected in different
degrees.  The first change appears to be that the veins become of a dull
reddish-orange.  The cells with chlorophyll next lose more or less
completely their green colour, and their contents finally become brown.
The parts thus affected often appeared almost black by reflected light;
but when viewed as a transparent object under the microscope, minute
specks of light were transmitted, and this was not the case with the
unaffected parts of the same leaves.  These effects, however, merely show
that the secreted fluid is highly injurious or poisonous to leaves; for
nearly the same effects were produced in from one to two days on various
kinds of young leaves, not only by artificial pancreatic fluid, prepared
with or without thymol, but quickly by a solution of thymol by itself.
On one occasion leaves of Corylus were much discoloured by being kept for
eighteen hours in pancreatic fluid, without any thymol.  With young and
tender leaves immersion in human saliva during rather warm weather, acted
in the same manner as the pancreatic fluid, but not so quickly.  The
leaves in all these cases often became infiltrated with the fluid.

Large leaves from an ivy plant growing on a wall were so tough that they
could not be gnawed by worms, but after four days they were affected in a
peculiar manner by the secretion poured out of their mouths.  The upper
surfaces of the leaves, over which the worms had crawled, as was shown by
the dirt left on them, were marked in sinuous lines, by either a
continuous or broken chain of whitish and often star-shaped dots, about 2
mm. in diameter.  The appearance thus presented was curiously like that
of a leaf, into which the larva of some minute insect had burrowed.  But
my son Francis, after making and examining sections, could nowhere find
that the cell-walls had been broken down or that the epidermis had been
penetrated.  When the section passed through the whitish dots, the grains
of chlorophyll were seen to be more or less discoloured, and some of the
palisade and mesophyll cells contained nothing but broken down granular
matter.  These effects must be attributed to the transudation of the
secretion through the epidermis into the cells.

The secretion with which worms moisten leaves likewise acts on the
starch-granules within the cells.  My son examined some leaves of the ash
and many of the lime, which had fallen off the trees and had been partly
dragged into worm-burrows.  It is known that with fallen leaves the
starch-grains are preserved in the guard-cells of the stomata.  Now in
several cases the starch had partially or wholly disappeared from these
cells, in the parts which had been moistened by the secretion; while it
was still well preserved in the other parts of the same leaves.
Sometimes the starch was dissolved out of only one of the two
guard-cells.  The nucleus in one case had disappeared, together with the
starch-granules.  The mere burying of lime-leaves in damp earth for nine
days did not cause the destruction of the starch-granules.  On the other
hand, the immersion of fresh lime and cherry leaves for eighteen hours in
artificial pancreatic fluid, led to the dissolution of the
starch-granules in the guard-cells as well as in the other cells.

From the secretion with which the leaves are moistened being alkaline,
and from its acting both on the starch-granules and on the protoplasmic
contents of the cells, we may infer that it resembles in nature not
saliva, {40} but pancreatic secretion; and we know from Fredericq that a
secretion of this kind is found in the intestines of worms.  As the
leaves which are dragged into the burrows are often dry and shrivelled,
it is indispensable for their disintegration by the unarmed mouths of
worms that they should first be moistened and softened; and fresh leaves,
however soft and tender they may be, are similarly treated, probably from
habit.  The result is that they are partially digested before they are
taken into the alimentary canal.  I am not aware of any other case of
extra-stomachal digestion having been recorded.  The boa-constrictor is
said to bathe its prey with saliva, but this is doubtful; and it is done
solely for the sake of lubricating its prey.  Perhaps the nearest analogy
may be found in such plants as Drosera and Dionæa; for here animal matter
is digested and converted into peptone not within a stomach, but on the
surfaces of the leaves.

_Calciferous Glands_.—These glands (see Fig. 1), judging from their size
and from their rich supply of blood-vessels, must be of much importance
to the animal.  But almost as many theories have been advanced on their
use as there have been observers.  They consist of three pairs, which in
the common earth-worm debouch into the alimentary canal in advance of the
gizzard, but posteriorly to it in Urochæta and some other genera. {41a}
The two posterior pairs are formed by lamellæ, which, according to
Claparède, are diverticula from the œsophagus. {41b}  These lamellæ are
coated with a pulpy cellular layer, with the outer cells lying free in
infinite numbers.  If one of these glands is punctured and squeezed, a
quantity of white pulpy matter exudes, consisting of these free cells.
They are minute, and vary in diameter from 2 to 6 _µ_.  They contain in
their centres a little excessively fine granular matter; but they look so
like oil globules that Claparède and others at first treated them with
ether.  This produces no effect; but they are quickly dissolved with
effervescence in acetic acid, and when oxalate of ammonia is added to the
solution a white precipitate is thrown down.  We may therefore conclude
that they contain carbonate of lime.  If the cells are immersed in a very
little acid, they become more transparent, look like ghosts, and are soon
lost to view; but if much acid is added, they disappear instantly.  After
a very large number have been dissolved, a flocculent residue is left,
which apparently consists of the delicate ruptured cell-walls.  In the
two posterior pairs of glands the carbonate of lime contained in the
cells occasionally aggregates into small rhombic crystals or into
concretions, which lie between the lamellæ; but I have seen only one
case, and Claparède only a very few such cases.

The two anterior glands differ a little in shape from the four posterior
ones, by being more oval.  They differ also conspicuously in generally
containing several small, or two or three larger, or a single very large
concretion of carbonate of lime, as much as 1½ mm. in diameter.  When a
gland includes only a few very small concretions, or, as sometimes
happens, none at all, it is easily overlooked.  The large concretions are
round or oval, and exteriorly almost smooth.  One was found which filled
up not only the whole gland, as is often the case, but its neck; so that
it resembled an olive-oil flask in shape.  These concretions when broken
are seen to be more or less crystalline in structure.  How they escape
from the gland is a marvel; but that they do escape is certain, for they
are often found in the gizzard, intestines, and in the castings of worms,
both with those kept in confinement and those in a state of nature.

Claparède says very little about the structure of the two anterior
glands, and he supposes that the calcareous matter of which the
concretions are formed is derived from the four posterior glands.  But if
an anterior gland which contains only small concretions is placed in
acetic acid and afterwards dissected, or if sections are made of such a
gland without being treated with acid, lamellæ like those in the
posterior glands and coated with cellular matter could be plainly seen,
together with a multitude of free calciferous cells readily soluble in
acetic acid.  When a gland is completely filled with a single large
concretion, there are no free cells, as these have been all consumed in
forming the concretion.  But if such a concretion, or one of only
moderately large size, is dissolved in acid, much membranous matter is
left, which appears to consist of the remains of the formerly active
lamellæ.  After the formation and expulsion of a large concretion, new
lamellæ must be developed in some manner.  In one section made by my son,
the process had apparently commenced, although the gland contained two
rather large concretions, for near the walls several cylindrical and oval
pipes were intersected, which were lined with cellular matter and were
quite filled with free calciferous cells.  A great enlargement in one
direction of several oval pipes would give rise to the lamellæ.

Besides the free calciferous cells in which no nucleus was visible, other
and rather larger free cells were seen on three occasions; and these
contained a distinct nucleus and nucleolus.  They were only so far acted
on by acetic acid that the nucleus was thus rendered more distinct.  A
very small concretion was removed from between two of the lamellæ within
an anterior gland.  It was imbedded in pulpy cellular matter, with many
free calciferous cells, together with a multitude of the larger, free,
nucleated cells, and these latter cells were not acted on by acetic acid,
while the former were dissolved.  From this and other such cases I am led
to suspect that the calciferous cells are developed from the larger
nucleated ones; but how this was effected was not ascertained.

When an anterior gland contains several minute concretions, some of these
are generally angular or crystalline in outline, while the greater number
are rounded with an irregular mulberry-like surface.  Calciferous cells
adhered to many parts of these mulberry-like masses, and their gradual
disappearance could be traced while they still remained attached.  It was
thus evident that the concretions are formed from the lime contained
within the free calciferous cells.  As the smaller concretions increase
in size, they come into contact and unite, thus enclosing the now
functionless lamellæ; and by such steps the formation of the largest
concretions could be followed.  Why the process regularly takes place in
the two anterior glands, and only rarely in the four posterior glands, is
quite unknown.  Morren says that these glands disappear during the
winter; and I have seen some instances of this fact, and others in which
either the anterior or posterior glands were at this season so shrunk and
empty, that they could be distinguished only with much difficulty.

With respect to the function of the calciferous glands, it is probable
that they primarily serve as organs of excretion, and secondarily as an
aid to digestion.  Worms consume many fallen leaves; and it is known that
lime goes on accumulating in leaves until they drop off the parent-plant,
instead of being re-absorbed into the stem or roots, like various other
organic and inorganic substances. {46}  The ashes of a leaf of an acacia
have been known to contain as much as 72 per cent. of lime.  Worms
therefore would be liable to become charged with this earth, unless there
were some special means for its excretion; and the calciferous glands are
well adapted for this purpose.  The worms which live in mould close over
the chalk, often have their intestines filled with this substance, and
their castings are almost white.  Here it is evident that the supply of
calcareous matter must be super-abundant.  Nevertheless with several
worms collected on such a site, the calciferous glands contained as many
free calciferous cells, and fully as many and large concretions, as did
the glands of worms which lived where there was little or no lime; and
this indicates that the lime is an excretion, and not a secretion poured
into the alimentary canal for some special purpose.

On the other hand, the following considerations render it highly probable
that the carbonate of lime, which is excreted by the glands, aids the
digestive process under ordinary circumstances.  Leaves during their
decay generate an abundance of various kinds of acids, which have been
grouped together under the term of humus acids.  We shall have to recur
to this subject in our fifth chapter, and I need here only say that these
acids act strongly on carbonate of lime.  The half-decayed leaves which
are swallowed in such large quantities by worms would, therefore, after
they have been moistened and triturated in the alimentary canal, be apt
to produce such acids.  And in the case of several worms, the contents of
the alimentary canal were found to be plainly acid, as shown by litmus
paper.  This acidity cannot be attributed to the nature of the digestive
fluid, for pancreatic fluid is alkaline; and we have seen that the
secretion which is poured out of the mouths of worms for the sake of
preparing the leaves for consumption, is likewise alkaline.  The acidity
can hardly be due to uric acid, as the contents of the upper part of the
intestine were often acid.  In one case the contents of the gizzard were
slightly acid, those of the upper intestines being more plainly acid.  In
another case the contents of the pharynx were not acid, those of the
gizzard doubtfully so, while those of the intestine were distinctly acid
at a distance of 5 cm. below the gizzard.  Even with the higher
herbivorous and omnivorous animals, the contents of the large intestine
are acid.  “This, however, is not caused by any acid secretion from the
mucous membrane; the reaction of the intestinal walls in the larger as in
the small intestine is alkaline.  It must therefore arise from acid
fermentations going on in the contents themselves . . .  In Carnivora the
contents of the coecum are said to be alkaline, and naturally the amount
of fermentation will depend largely on the nature of the food.” {49}

With worms not only the contents of the intestines, but their ejected
matter or the castings, are generally acid.  Thirty castings from
different places were tested, and with three or four exceptions were
found to be acid; and the exceptions may have been due to such castings
not having been recently ejected; for some which were at first acid, were
on the following morning, after being dried and again moistened, no
longer acid; and this probably resulted from the humus acids being, as is
known to be the case, easily decomposed.  Five fresh castings from worms
which lived in mould close over the chalk, were of a whitish colour and
abounded with calcareous matter; and these were not in the least acid.
This shows how effectually carbonate of lime neutralises the intestinal
acids.  When worms were kept in pots filled with fine ferruginous sand,
it was manifest that the oxide of iron, with which the grains of silex
were coated, had been dissolved and removed from them in the castings.

The digestive fluid of worms resembles in its action, as already stated,
the pancreatic secretion of the higher animals; and in these latter,
“pancreatic digestion is essentially alkaline; the action will not take
place unless some alkali be present; and the activity of an alkaline
juice is arrested by acidification, and hindered by neutralization.” {50}
Therefore it seems highly probable that the innumerable calciferous
cells, which are poured from the four posterior glands into the
alimentary canal of worms, serve to neutralise more or less completely
the acids there generated by the half-decayed leaves.  We have seen that
these cells are instantly dissolved by a small quantity of acetic acid,
and as they do not always suffice to neutralise the contents of even the
upper part of the alimentary canal, the lime is perhaps aggregated into
concretions in the anterior pair of glands, in order that some may be
carried down to the posterior parts of the intestine, where these
concretions would be rolled about amongst the acid contents.  The
concretions found in the intestines and in the castings often have a worn
appearance, but whether this is due to some amount of attrition or of
chemical corrosion could not be told.  Claparède believes that they are
formed for the sake of acting as mill-stones, and of thus aiding in the
trituration of the food.  They may give some aid in this way; but I fully
agree with Perrier that this must be of quite subordinate importance,
seeing that the object is already attained by stones being generally
present in the gizzards and intestines of worms.




CHAPTER II.
HABITS OF WORMS—_continued_.


Manner in which worms seize objects—Their power of suction—The instinct
of plugging up the mouths of their burrows—Stones piled over the
burrows—The advantages thus gained—Intelligence shown by worms in their
manner of plugging up their burrows—Various kinds of leaves and other
objects thus used—Triangles of paper—Summary of reasons for believing
that worms exhibit some intelligence—Means by which they excavate their
burrows, by pushing away the earth and swallowing it—Earth also swallowed
for the nutritious matter which it contains—Depth to which worms burrow,
and the construction of their burrows—Burrows lined with castings, and in
the upper part with leaves—The lowest part paved with little stones or
seeds—Manner in which the castings are ejected—The collapse of old
burrows—Distribution of worms—Tower-like castings in Bengal—Gigantic
castings on the Nilgiri Mountains—Castings ejected in all countries.

IN the pots in which worms were kept, leaves were pinned down to the
soil, and at night the manner in which they were seized could be
observed.  The worms always endeavoured to drag the leaves towards their
burrows; and they tore or sucked off small fragments, whenever the leaves
were sufficiently tender.  They generally seized the thin edge of a leaf
with their mouths, between the projecting upper and lower lip; the thick
and strong pharynx being at the same time, as Perrier remarks, pushed
forward within their bodies, so as to afford a point of resistance for
the upper lip.  In the case of broad flat objects they acted in a wholly
different manner.  The pointed anterior extremity of the body, after
being brought into contact with an object of this kind, was drawn within
the adjoining rings, so that it appeared truncated and became as thick as
the rest of the body.  This part could then be seen to swell a little;
and this, I believe, is due to the pharynx being pushed a little
forwards.  Then by a slight withdrawal of the pharynx or by its
expansion, a vacuum was produced beneath the truncated slimy end of the
body whilst in contact with the object; and by this means the two adhered
firmly together. {53}  That under these circumstances a vacuum was
produced was plainly seen on one occasion, when a large worm lying
beneath a flaccid cabbage leaf tried to drag it away; for the surface of
the leaf directly over the end of the worm’s body became deeply pitted.
On another occasion a worm suddenly lost its hold on a flat leaf; and the
anterior end of the body was momentarily seen to be cup-formed.  Worms
can attach themselves to an object beneath water in the same manner; and
I saw one thus dragging away a submerged slice of an onion-bulb.

The edges of fresh or nearly fresh leaves affixed to the ground were
often nibbled by the worms; and sometimes the epidermis and all the
parenchyma on one side was gnawed completely away over a considerable
space; the epidermis alone on the opposite side being left quite clean.
The veins were never touched, and leaves were thus sometimes partly
converted into skeletons.  As worms have no teeth and as their mouths
consist of very soft tissue, it may be presumed that they consume by
means of suction the edges and the parenchyma of fresh leaves, after they
have been softened by the digestive fluid.  They cannot attack such
strong leaves as those of sea-kale or large and thick leaves of ivy;
though one of the latter after it had become rotten was reduced in parts
to the state of a skeleton.

Worms seize leaves and other objects, not only to serve as food, but for
plugging up the mouths of their burrows; and this is one of their
strongest instincts.  They sometimes work so energetically that Mr. D. F.
Simpson, who has a small walled garden where worms abound in Bayswater,
informs me that on a calm damp evening he there heard so extraordinary a
rustling noise from under a tree from which many leaves had fallen, that
he went out with a light and discovered that the noise was caused by many
worms dragging the dry leaves and squeezing them into the burrows.  Not
only leaves, but petioles of many kinds, some flower-peduncles, often
decayed twigs of trees, bits of paper, feathers, tufts of wool and
horse-hairs are dragged into their burrows for this purpose.  I have seen
as many as seventeen petioles of a Clematis projecting from the mouth of
one burrow, and ten from the mouth of another.  Some of these objects,
such as the petioles just named, feathers, &c., are never gnawed by
worms.  In a gravel-walk in my garden I found many hundred leaves of a
pine-tree (_P. austriaca_ or _nigricans_) drawn by their bases into
burrows.  The surfaces by which these leaves are articulated to the
branches are shaped in as peculiar a manner as is the joint between the
leg-bones of a quadruped; and if these surfaces had been in the least
gnawed, the fact would have been immediately visible, but there was no
trace of gnawing.  Of ordinary dicotyledonous leaves, all those which are
dragged into burrows are not gnawed.  I have seen as many as nine leaves
of the lime-tree drawn into the same burrow, and not nearly all of them
had been gnawed; but such leaves may serve as a store for future
consumption.  Where fallen leaves are abundant, many more are sometimes
collected over the mouth of a burrow than can be used, so that a small
pile of unused leaves is left like a roof over those which have been
partly dragged in.

A leaf in being dragged a little way into a cylindrical burrow is
necessarily much folded or crumpled.  When another leaf is drawn in, this
is done exteriorly to the first one, and so on with the succeeding
leaves; and finally all become closely folded and pressed together.
Sometimes the worm enlarges the mouth of its burrow, or makes a fresh one
close by, so as to draw in a still larger number of leaves.  They often
or generally fill up the interstices between the drawn-in leaves with
moist viscid earth ejected from their bodies; and thus the mouths of the
burrows are securely plugged.  Hundreds of such plugged burrows may be
seen in many places, especially during the autumnal and early winter
months.  But, as will hereafter be shown, leaves are dragged into the
burrows not only for plugging them up and for food, but for the sake of
lining the upper part or mouth.

When worms cannot obtain leaves, petioles, sticks, &c., with which to
plug up the mouths of their burrows, they often protect them by little
heaps of stones; and such heaps of smooth rounded pebbles may frequently
be seen on gravel-walks.  Here there can be no question about food.  A
lady, who was interested in the habits of worms, removed the little heaps
of stones from the mouths of several burrows and cleared the surface of
the ground for some inches all round.  She went out on the following
night with a lantern, and saw the worms with their tails fixed in their
burrows, dragging the stones inwards by the aid of their mouths, no doubt
by suction.  “After two nights some of the holes had 8 or 9 small stones
over them; after four nights one had about 30, and another 34 stones.”
{58}  One stone—which had been dragged over the gravel-walk to the mouth
of a burrow weighed two ounces; and this proves how strong worms are.
But they show greater strength in sometimes displacing stones in a
well-trodden gravel-walk; that they do so, may be inferred from the
cavities left by the displaced stones being exactly filled by those lying
over the mouths of adjoining burrows, as I have myself observed.

Work of this kind is usually performed during the night; but I have
occasionally known objects to be drawn into the burrows during the day.
What advantage the worms derive from plugging up the mouths of their
burrows with leaves, &c., or from piling stones over them, is doubtful.
They do not act in this manner at the times when they eject much earth
from their burrows; for their castings then serve to cover the mouths.
When gardeners wish to kill worms on a lawn, it is necessary first to
brush or rake away the castings from the surface, in order that the
lime-water may enter the burrows. {59a}  It might be inferred from this
fact that the mouths are plugged up with leaves, &c., to prevent the
entrance of water during heavy rain; but it may be urged against this
view that a few, loose, well-rounded stones are ill-adapted to keep out
water.  I have moreover seen many burrows in the perpendicularly cut
turf-edgings to gravel-walks, into which water could hardly flow, as well
plugged as burrows on a level surface.  It is not probable that the plugs
or piles of stones serve to conceal the burrows from scolopendras, which,
according to Hoffmeister, {59b} are the bitterest enemies of worms, or
from the larger species of Carabus and Staphylinus which attack them
ferociously, for these animals are nocturnal, and the burrows are opened
at night.  May not worms when the mouth of the burrow is protected be
able to remain with safety with their heads close to it, which we know
that they like to do, but which costs so many of them their lives?  Or
may not the plugs check the free ingress of the lowest stratum of air,
when chilled by radiation at night, from the surrounding ground and
herbage?  I am inclined to believe in this latter view: firstly, because
when worms were kept in pots in a room with a fire, in which case cold
air could not enter the burrows, they plugged them up in a slovenly
manner; and secondarily, because they often coat the upper part of their
burrows with leaves, apparently to prevent their bodies from coming into
close contact with the cold damp earth.  Mr. E. Parfitt has suggested to
me that the mouths of the burrows are closed in order that the air within
them may be kept thoroughly damp, and this seems the most probable
explanation of the habit.  But the plugging-up process may serve for all
the above purposes.

Whatever the motive may be, it appears that worms much dislike leaving
the mouths of their burrows open.  Nevertheless they will reopen them at
night, whether or not they can afterwards close them.  Numerous open
burrows may be seen on recently-dug ground, for in this case the worms
eject their castings in cavities left in the ground, or in the old
burrows instead of piling them over the mouths of their burrows, and they
cannot collect objects on the surface by which the mouths might be
protected.  So again on a recently disinterred pavement of a Roman villa
at Abinger (hereafter to be described) the worms pertinaciously opened
their burrows almost every night, when these had been closed by being
trampled on, although they were rarely able to find a few minute stones
wherewith to protect them.

_Intelligence shown by worms in their manner of plugging up their
burrows_.—If a man had to plug up a small cylindrical hole, with such
objects as leaves, petioles or twigs, he would drag or push them in by
their pointed ends; but if these objects were very thin relatively to the
size of the hole, he would probably insert some by their thicker or
broader ends.  The guide in his case would be intelligence.  It seemed
therefore worth while to observe carefully how worms dragged leaves into
their burrows; whether by their tips or bases or middle parts.  It seemed
more especially desirable to do this in the case of plants not natives to
our country; for although the habit of dragging leaves into their burrows
is undoubtedly instinctive with worms, yet instinct could not tell them
how to act in the case of leaves about which their progenitors knew
nothing.  If, moreover, worms acted solely through instinct or an
unvarying inherited impulse, they would draw all kinds of leaves into
their burrows in the same manner.  If they have no such definite
instinct, we might expect that chance would determine whether the tip,
base or middle was seized.  If both these alternatives are excluded,
intelligence alone is left; unless the worm in each case first tries many
different methods, and follows that alone which proves possible or the
most easy; but to act in this manner and to try different methods makes a
near approach to intelligence.

In the first place 227 withered leaves of various kinds, mostly of
English plants, were pulled out of worm-burrows in several places.  Of
these, 181 had been drawn into the burrows by or near their tips, so that
the foot-stalk projected nearly upright from the mouth of the burrow; 20
had been drawn in by their bases, and in this case the tips projected
from the burrows; and 26 had been seized near the middle, so that these
had been drawn in transversely and were much crumpled.  Therefore 80 per
cent. (always using the nearest whole number) had been drawn in by the
tip, 9 per cent. by the base or foot-stalk, and 11 per cent. transversely
or by the middle.  This alone is almost sufficient to show that chance
does not determine the manner in which leaves are dragged into the
burrows.

Of the above 227 leaves, 70 consisted of the fallen leaves of the common
lime-tree, which is almost certainly not a native of England.  These
leaves are much acuminated towards the tip, and are very broad at the
base with a well-developed foot-stalk.  They are thin and quite flexible
when half-withered.  Of the 70, 79 per cent. had been drawn in by or near
the tip; 4 per cent. by or near the base; and 17 per cent. transversely
or by the middle.  These proportions agree very closely, as far as the
tip is concerned, with those before given.  But the percentage drawn in
by the base is smaller, which may be attributed to the breadth of the
basal part of the blade.  We here, also, see that the presence of a
foot-stalk, which it might have been expected would have tempted the
worms as a convenient handle, has little or no influence in determining
the manner in which lime leaves are dragged into the burrows.  The
considerable proportion, viz., 17 per cent., drawn in more or less
transversely depends no doubt on the flexibility of these half-decayed
leaves.  The fact of so many having been drawn in by the middle, and of
some few having been drawn in by the base, renders it improbable that the
worms first tried to draw in most of the leaves by one or both of these
methods, and that they afterwards drew in 79 per cent. by their tips; for
it is clear that they would not have failed in drawing them in by the
base or middle.

The leaves of a foreign plant were next searched for, the blades of which
were not more pointed towards the apex than towards the base.  This
proved to be the case with those of a laburnum (a hybrid between _Cytisus
alpinus_ and _laburnum_) for on doubling the terminal over the basal
half, they generally fitted exactly; and when there was any difference,
the basal half was a little the narrower.  It might, therefore, have been
expected that an almost equal number of these leaves would have been
drawn in by the tip and base, or a slight excess in favour of the latter.
But of 73 leaves (not included in the first lot of 227) pulled out of
worm-burrows, 63 per cent. had been drawn in by the tip; 27 per cent. by
the base, and 10 per cent. transversely.  We here see that a far larger
proportion, viz., 27 per cent. were drawn in by the base than in the case
of lime leaves, the blades of which are very broad at the base, and of
which only 4 per cent. had thus been drawn in.  We may perhaps account
for the fact of a still larger proportion of the laburnum leaves not
having been drawn in by the base, by worms having acquired the habit of
generally drawing in leaves by their tips and thus avoiding the
foot-stalk.  For the basal margin of the blade in many kinds of leaves
forms a large angle with the foot-stalk; and if such a leaf were drawn in
by the foot-stalk, the basal margin would come abruptly into contact with
the ground on each side of the burrow, and would render the drawing in of
the leaf very difficult.

Nevertheless worms break through their habit of avoiding the foot-stalk,
if this part offers them the most convenient means for drawing leaves
into their burrows.  The leaves of the endless hybridised varieties of
the Rhododendron vary much in shape; some are narrowest towards the base
and others towards the apex.  After they have fallen off, the blade on
each side of the midrib often becomes curled up while drying, sometimes
along the whole length, sometimes chiefly at the base, sometimes towards
the apex.  Out of 28 fallen leaves on one bed of peat in my garden, no
less than 23 were narrower in the basal quarter than in the terminal
quarter of their length; and this narrowness was chiefly due to the
curling in of the margins.  Out of 36 fallen leaves on another bed, in
which different varieties of the Rhododendron grew, only 17 were narrower
towards the base than towards the apex.  My son William, who first called
my attention to this case, picked up 237 fallen leaves in his garden
(where the Rhododendron grows in the natural soil) and of these 65 per
cent. could have been drawn by worms into their burrows more easily by
the base or foot-stalk than by the tip; and this was partly due to the
shape of the leaf and in a less degree to the curling in of the margins:
27 per cent. could have been drawn in more easily by the tip than by the
base: and 8 per cent. with about equal ease by either end.  The shape of
a fallen leaf ought to be judged of before one end has been drawn into a
burrow, for after this has happened, the free end, whether it be the base
or apex, will dry more quickly than the end imbedded in the damp ground;
and the exposed margins of the free end will consequently tend to become
more curled inwards than they were when the leaf was first seized by the
worm.  My son found 91 leaves which had been dragged by worms into their
burrows, though not to a great depth; of these 66 per cent. had been
drawn in by the base or foot-stalk; and 34 per cent. by the tip.  In this
case, therefore, the worms judged with a considerable degree of
correctness how best to draw the withered leaves of this foreign plant
into their burrows; notwithstanding that they had to depart from their
usual habit of avoiding the foot-stalk.

On the gravel-walks in my garden a very large number of leaves of three
species of Pinus (_P. austriaca_, _nigricans_ and _sylvestris_) are
regularly drawn into the mouths of worm burrows.  These leaves consist of
two so-called needles, which are of considerable length in the two first
and short in the last named species, and are united to a common base; and
it is by this part that they are almost invariably drawn into the
burrows.  I have seen only two or at most three exceptions to this rule
with worms in a state of nature.  As the sharply pointed needles diverge
a little, and as several leaves are drawn into the same burrow, each tuft
forms a perfect _chevaux de frise_.  On two occasions many of these tufts
were pulled up in the evening, but by the following morning fresh leaves
had been pulled in, and the burrows were again well protected.  These
leaves could not be dragged into the burrows to any depth, except by
their bases, as a worm cannot seize hold of the two needles at the same
time, and if one alone were seized by the apex, the other would be
pressed against the ground and would resist the entry of the seized one.
This was manifest in the above mentioned two or three exceptional cases.
In order, therefore, that worms should do their work well, they must drag
pine-leaves into their burrows by their bases, where the two needles are
conjoined.  But how they are guided in this work is a perplexing
question.

This difficulty led my son Francis and myself to observe worms in
confinement during several nights by the aid of a dim light, while they
dragged the leaves of the above named pines into their burrows.  They
moved the anterior extremities of their bodies about the leaves, and on
several occasions when they touched the sharp end of a needle they
withdrew suddenly as if pricked.  But I doubt whether they were hurt, for
they are indifferent to very sharp objects, and will swallow even
rose-thorns and small splinters of glass.  It may also be doubted,
whether the sharp ends of the needles serve to tell them that this is the
wrong end to seize; for the points were cut off many leaves for a length
of about one inch, and fifty-seven of them thus treated were drawn into
the burrows by their bases, and not one by the cut-off ends.  The worms
in confinement often seized the needles near the middle and drew them
towards the mouths of their burrows; and one worm tried in a senseless
manner to drag them into the burrow by bending them.  They sometimes
collected many more leaves over the mouths of their burrows (as in the
case formerly mentioned of lime-leaves) than could enter them.  On other
occasions, however, they behaved very differently; for as soon as they
touched the base of a pine-leaf, this was seized, being sometimes
completely engulfed in their mouths, or a point very near the base was
seized, and the leaf was then quickly dragged or rather jerked into their
burrows.  It appeared both to my son and myself as if the worms instantly
perceived as soon as they had seized a leaf in the proper manner.  Nine
such cases were observed, but in one of them the worm failed to drag the
leaf into its burrow, as it was entangled by other leaves lying near.  In
another case a leaf stood nearly upright with the points of the needles
partly inserted into a burrow, but how placed there was not seen; and
then the worm reared itself up and seized the base, which was dragged
into the mouth of the burrow by bowing the whole leaf.  On the other
hand, after a worm had seized the base of a leaf, this was on two
occasions relinquished from some unknown motive.

As already remarked, the habit of plugging up the mouths of the burrows
with various objects, is no doubt instinctive in worms; and a very young
one, born in one of my pots, dragged for some little distance a
Scotch-fir leaf, one needle of which was as long and almost as thick as
its own body.  No species of pine is endemic in this part of England, it
is therefore incredible that the proper manner of dragging pine-leaves
into the burrows can be instinctive with our worms.  But as the worms on
which the above observations were made, were dug up beneath or near some
pines, which had been planted there about forty years, it was desirable
to prove that their actions were not instinctive.  Accordingly,
pine-leaves were scattered on the ground in places far removed from any
pine-tree, and 90 of them were drawn into the burrows by their bases.
Only two were drawn in by the tips of the needles, and these were not
real exceptions, as one was drawn in for a very short distance, and the
two needles of the other cohered.  Other pine-leaves were given to worms
kept in pots in a warm room, and here the result was different; for out
of 42 leaves drawn into the burrows, no less than 16 were drawn in by the
tips of the needles.  These worms, however, worked in a careless or
slovenly manner; for the leaves were often drawn in to only a small
depth; sometimes they were merely heaped over the mouths of the burrows,
and sometimes none were drawn in.  I believe that this carelessness may
be accounted for either by the warmth of the air, or by its dampness, as
the pots were covered by glass plates; the worms consequently did not
care about plugging up their holes effectually.  Pots tenanted by worms
and covered with a net which allowed the free entrance of air, were left
out of doors for several nights, and now 72 leaves were all properly
drawn in by their bases.

It might perhaps be inferred from the facts as yet given, that worms
somehow gain a general notion of the shape or structure of pine-leaves,
and perceive that it is necessary for them to seize the base where the
two needles are conjoined.  But the following cases make this more than
doubtful.  The tips of a large number of needles of _P. austriaca_ were
cemented together with shell-lac dissolved in alcohol, and were kept for
some days, until, as I believe, all odour or taste had been lost; and
they were then scattered on the ground where no pine-trees grew, near
burrows from which the plugging had been removed.  Such leaves could have
been drawn into the burrows with equal ease by either end; and judging
from analogy and more especially from the case presently to be given of
the petioles of _Clematis montana_, I expected that the apex would have
been preferred.  But the result was that out of 121 leaves with the tips
cemented, which were drawn into burrows, 108 were drawn in by their
bases, and only 13 by their tips.  Thinking that the worms might possibly
perceive and dislike the smell or taste of the shell-lac, though this was
very improbable, especially after the leaves had been left out during
several nights, the tips of the needles of many leaves were tied together
with fine thread.  Of leaves thus treated 150 were drawn into burrows—123
by the base and 27 by the tied tips; so that between four land five times
as many were drawn in by the base as by the tip.  It is possible that the
short cut-off ends of the thread with which they were tied, may have
tempted the worms to drag in a larger proportional number by the tips
than when cement was used.  Of the leaves with tied and cemented tips
taken together (271 in number) 85 per cent. were drawn in by the base and
15 per cent. by the tips.  We may therefore infer that it is not the
divergence of the two needles which leads worms in a state of nature
almost invariably to drag pine-leaves into their burrows by the base.
Nor can it be the sharpness of the points of the needles which determines
them; for, as we have seen, many leaves with the points cut off were
drawn in by their bases.  We are thus led to conclude, that with
pine-leaves there must be something attractive to worms in the base,
notwithstanding that few ordinary leaves are drawn in by the base or
foot-stalk.

_Petioles_.—We will now turn to the petioles or foot-stalks of compound
leaves, after the leaflets have fallen off.  Those from _Clematis
montana_, which grew over a verandah, were dragged early in January in
large numbers into the burrows on an adjoining gravel-walk, lawn, and
flower-bed.  These petioles vary from 2½ to 4½ inches in length, are
rigid and of nearly uniform thickness, except close to the base where
they thicken rather abruptly, being here about twice as thick as in any
other part.  The apex is somewhat pointed, but soon withers and is then
easily broken off.  Of these petioles, 314 were pulled out of burrows in
the above specified sites; and it was found that 76 per cent. had been
drawn in by their tips, and 24 per cent by their bases; so that those
drawn in by the tip were a little more than thrice as many as those drawn
in by the base.  Some of those extracted from the well-beaten gravel-walk
were kept separate from the others; and of these (59 in number) nearly
five times as many had been drawn in by the tip as by the base; whereas
of those extracted from the lawn and flower-bed, where from the soil
yielding more easily, less care would be necessary in plugging up the
burrows, the proportion of those drawn in by the tip (130) to those drawn
in by the base (48) was rather less than three to one.  That these
petioles had been dragged into the burrows for plugging them up, and not
for food, was manifest, as neither end, as far as I could see, had been
gnawed.  As several petioles are used to plug up the same burrow, in one
case as many as 10, and in another case as many as 15, the worms may
perhaps at first draw in a few by the thicker end so as to save labour;
but afterwards a large majority are drawn in by the pointed end, in order
to plug up the hole securely.

The fallen petioles of our native ash-tree were next observed, and the
rule with most objects, viz., that a large majority are dragged into the
burrows by the more pointed end, had not here been followed; and this
fact much surprised me at first.  These petioles vary in length from 5 to
8½ inches; they are thick and fleshy towards the base, whence they taper
gently towards the apex, which is a little enlarged and truncated where
the terminal leaflet had been originally attached.  Under some ash-trees
growing in a grass-field, 229 petioles were pulled out of worm burrows
early in January, and of these 51.5 per cent. had been drawn in by the
base, and 48.5 per cent. by the apex.  This anomaly was however readily
explained as soon as the thick basal part was examined; for in 78 out of
103 petioles, this part had been gnawed by worms, just above the
horse-shoe shaped articulation.  In most cases there could be no mistake
about the gnawing; for ungnawed petioles which were examined after being
exposed to the weather for eight additional weeks had not become more
disintegrated or decayed near the base than elsewhere.  It is thus
evident that the thick basal end of the petiole is drawn in not solely
for the sake of plugging up the mouths of the burrows, but as food.  Even
the narrow truncated tips of some few petioles had been gnawed; and this
was the case in 6 out of 37 which were examined for this purpose.  Worms,
after having drawn in and gnawed the basal end, often push the petioles
out of their burrows; and then drag in fresh ones, either by the base for
food, or by the apex for plugging up the mouth more effectually.  Thus,
out of 37 petioles inserted by their tips, 5 had been previously drawn in
by the base, for this part had been gnawed.  Again, I collected a handful
of petioles lying loose on the ground close to some plugged-up burrows,
where the surface was thickly strewed with other petioles which
apparently had never been touched by worms; and 14 out of 47 (_i.e._
nearly one-third), after having had their bases gnawed had been pushed
out of the burrows and were now lying on the ground.  From these several
facts we may conclude that worms draw in some petioles of the ash by the
base to serve as food, and others by the tip to plug up the mouths of
their burrows in the most efficient manner.

The petioles of _Robinia pseudo-acacia_ vary from 4 or 5 to nearly 12
inches in length; they are thick close to the base before the softer
parts have rotted off, and taper much towards the upper end.  They are so
flexible that I have seen some few doubled up and thus drawn into the
burrows of worms.  Unfortunately these petioles were not examined until
February, by which time the softer parts had completely rotted off, so
that it was impossible to ascertain whether worms had gnawed the bases,
though this is in itself probable.  Out of 121 petioles extracted from
burrows early in February, 68 were imbedded by the base, and 53 by the
apex.  On February 5 all the petioles which had been drawn into the
burrows beneath a Robinia, were pulled up; and after an interval of
eleven days, 35 petioles had been again dragged in, 19 by the base, and
16 by the apex.  Taking these two lots together, 56 per cent. were drawn
in by the base, and 44 per cent. by the apex.  As all the softer parts
had long ago rotted off, we may feel sure, especially in the latter case,
that none had been drawn in as food.  At this season, therefore, worms
drag these petioles into their burrows indifferently by either end, a
slight preference being given to the base.  This latter fact may be
accounted for by the difficulty of plugging up a burrow with objects so
extremely thin as are the upper ends.  In support of this view, it may be
stated that out of the 16 petioles which had been drawn in by their upper
ends, the more attenuated terminal portion of 7 had been previously
broken off by some accident.

_Triangles of paper_.—Elongated triangles were cut out of moderately
stiff writing-paper, which was rubbed with raw fat on both sides, so as
to prevent their becoming excessively limp when exposed at night to rain
and dew.  The sides of all the triangles were three inches in length,
with the bases of 120 one inch, and of the other 183 half an inch in
length.  These latter triangles were very narrow or much acuminated. {79}
As a check on the observations presently to be given, similar triangles
in a damp state were seized by a very narrow pair of pincers at different
points and at all inclinations with reference to the margins, and were
then drawn into a short tube of the diameter of a worm-burrow.  If seized
by the apex, the triangle was drawn straight into the tube, with its
margins infolded; if seized at some little distance from the apex, for
instance at half an inch, this much was doubled back within the tube.  So
it was with the base and basal angles, though in this case the triangles
offered, as might have been expected, much more resistance to being drawn
in.  If seized near the middle the triangle was doubled up, with the apex
and base left sticking out of the tube.  As the sides of the triangles
were three inches in length, the result of their being drawn into a tube
or into a burrow in different ways, may be conveniently divided into
three groups: those drawn in by the apex or within an inch of it; those
drawn in by the base or within an inch of it; and those drawn in by any
point in the middle inch.

In order to see how the triangles would be seized by worms, some in a
damp state were given to worms kept in confinement.  They were seized in
three different manners in the case of both the narrow and broad
triangles: viz., by the margin; by one of the three angles, which was
often completely engulfed in their mouths; and lastly, by suction applied
to any part of the flat surface.  If lines parallel to the base and an
inch apart, are drawn across a triangle with the sides three inches in
length, it will be divided into three parts of equal length.  Now if
worms seized indifferently by chance any part, they would assuredly seize
on the basal part or division far oftener than on either of the two other
divisions.  For the area of the basal to the apical part is as 5 to 1, so
that the chance of the former being drawn into a burrow by suction, will
be as 5 to 1, compared with the apical part.  The base offers two angles
and the apex only one, so that the former would have twice as good a
chance (independently of the size of the angles) of being engulfed in a
worm’s mouth, as would the apex.  It should, however, be stated that the
apical angle is not often seized by worms; the margin at a little
distance on either side being preferred.  I judge of this from having
found in 40 out of 46 cases in which triangles had been drawn into
burrows by their apical ends, that the tip had been doubled back within
the burrow for a length of between 1/20 of an inch and 1 inch.  Lastly,
the proportion between the margins of the basal and apical parts is as 3
to 2 for the broad, and 2½ to 2 for the narrow triangles.  From these
several considerations it might certainly have been expected, supposing
that worms seized hold of the triangles by chance, that a considerably
larger proportion would have been dragged into the burrows by the basal
than by the apical part; but we shall immediately see how different was
the result.

Triangles of the above specified sizes were scattered on the ground in
many places and on many successive nights near worm-burrows, from which
the leaves, petioles, twigs, &c., with which they had been plugged, were
removed.  Altogether 303 triangles were drawn by worms into their
burrows: 12 others were drawn in by both ends, but as it was impossible
to judge by which end they had been first seized, these are excluded.  Of
the 303, 62 per cent. had been drawn in by the apex (using this term for
all drawn in by the apical part, one inch in length); 15 per cent. by the
middle; and 23 per cent. by the basal part.  If they had been drawn
indifferently by any point, the proportion for the apical, middle and
basal parts would have been 33.3 per cent. for each; but, as we have just
seen, it might have been expected that a much larger proportion would
have been drawn in by the basal than by any other part.  As the case
stands, nearly three times as many were drawn in by the apex as by the
base.  If we consider the broad triangles by themselves, 59 per cent.
were drawn in by the apex, 25 per cent. by the middle, and 16 per cent.
by the base.  Of the narrow triangles, 65 per cent. were drawn in by the
apex, 14 per cent, by the middle, and 21 per cent. by the base; so that
here those drawn in by the apex were more than 3 times as many as those
drawn in by the base.  We may therefore conclude that the manner in which
the triangles are drawn into the burrows is not a matter of chance.

In eight cases, two triangles had been drawn into the same burrow, and in
seven of these cases, one had been drawn in by the apex and the other by
the base.  This again indicates that the result is not determined by
chance.  Worms appear sometimes to revolve in the act of drawing in the
triangles, for five out of the whole lot had been wound into an irregular
spire round the inside of the burrow.  Worms kept in a warm room drew 63
triangles into their burrows; but, as in the case of the pine-leaves,
they worked in a rather careless manner, for only 44 per cent. were drawn
in by the apex, 22 per cent. by the middle, and 33 per cent. by the base.
In five cases, two triangles were drawn into the same burrow.

It may be suggested with much apparent probability that so large a
proportion of the triangles were drawn in by the apex, not from the worms
having selected this end as the most convenient for the purpose, but from
having first tried in other ways and failed.  This notion was
countenanced by the manner in which worms in confinement were seen to
drag about and drop the triangles; but then they were working carelessly.
I did not at first perceive the importance of this subject, but merely
noticed that the bases of those triangles which had been drawn in by the
apex, were generally clean and not crumpled.  The subject was afterwards
attended to carefully.  In the first place several triangles which had
been drawn in by the basal angles, or by the base, or a little above the
base, and which were thus much crumpled and dirtied, were left for some
hours in water and were then well shaken while immersed; but neither the
dirt nor the creases were thus removed.  Only slight creases could be
obliterated, even by pulling the wet triangles several times through my
fingers.  Owing to the slime from the worms’ bodies, the dirt was not
easily washed off.  We may therefore conclude that if a triangle, before
being dragged in by the apex, had been dragged into a burrow by its base
with even a slight degree of force, the basal part would long retain its
creases and remain dirty.  The condition of 89 triangles (65 narrow and
24 broad ones), which had been drawn in by the apex, was observed; and
the bases of only 7 of them were at all creased, being at the same time
generally dirty.  Of the 82 uncreased triangles, 14 were dirty at the
base; but it does not follow from this fact that these had first been
dragged towards the burrows by their bases; for the worms sometimes
covered large portions of the triangles with slime, and these when
dragged by the apex over the ground would be dirtied; and during rainy
weather, the triangles were often dirtied over one whole side or over
both sides.  If the worms had dragged the triangles to the mouths of
their burrows by their bases, as often as by their apices, and had then
perceived, without actually trying to draw them into the burrow, that the
broader end was not well adapted for this purpose—even in this case a
large proportion would probably have had their basal ends dirtied.  We
may therefore infer—improbable as is the inference—that worms are able by
some means to judge which is the best end by which to draw triangles of
paper into their burrows.

The percentage results of the foregoing observations on the manner in
which worms draw various kinds of objects into the mouths of their
burrows may be abridged as follows:—

   Nature of       Drawn into the   Drawn in, by or   Drawn in, by or
    Object.        burrows, by or       near the       near the base.
                   near the apex.       middle.
Leaves of                       80                11                 9
various kinds
—of the Lime,                   79                17                 4
basal margin of
blade broad,
apex acuminated
—of a Laburnum,                 63                10                27
basal part of
blade as narrow
as, or
sometimes
little narrower
than the apical
part
—of the                         34        ...                       66
Rhododendron,
basal part of
blade often
narrower than
the apical part
—of Pine-trees,         ...               ...                      100
consisting of
two needles
arising from a
common base
Petioles of a                   76        ...                       24
Clematis,
somewhat
pointed at the
apex, and blunt
at the base
—of the Ash,                  48.5        ...                     51.5
the thick basal
end often drawn
in to serve as
food
—of Robinia,                    44        ...                       56
extremely thin,
especially
towards the
apex, so as to
be ill-fitted
for plugging up
the burrows
Triangles of                    62                15                23
paper, of the
two sizes
—of the broad                   59                25                16
ones alone
—of the narrow                  65                14                21
ones alone

If we consider these several cases, we can hardly escape from the
conclusion that worms show some degree of intelligence in their manner of
plugging up their burrows.  Each particular object is seized in too
uniform a manner, and from causes which we can generally understand, for
the result to be attributed to mere chance.  That every object has not
been drawn in by its pointed end, may be accounted for by labour having
been saved through some being inserted by their broader or thicker ends.
No doubt worms are led by instinct to plug up their burrows; and it might
have been expected that they would have been led by instinct how best to
act in each particular case, independently of intelligence.  We see how
difficult it is to judge whether intelligence comes into play, for even
plants might sometimes be thought to be thus directed; for instance when
displaced leaves re-direct their upper surfaces towards the light by
extremely complicated movements and by the shortest course.  With
animals, actions appearing due to intelligence may be performed through
inherited habit without any intelligence, although aboriginally thus
acquired.  Or the habit may have been acquired through the preservation
and inheritance of beneficial variations of some other habit; and in this
case the new habit will have been acquired independently of intelligence
throughout the whole course of its development.  There is no _à priori_
improbability in worms having acquired special instincts through either
of these two latter means.  Nevertheless it is incredible that instincts
should have been developed in reference to objects, such as the leaves of
petioles of foreign plants, wholly unknown to the progenitors of the
worms which act in the described manner.  Nor are their actions so
unvarying or inevitable as are most true instincts.

As worms are not guided by special instincts in each particular case,
though possessing a general instinct to plug up their burrows, and as
chance is excluded, the next most probable conclusion seems to be that
they try in many different ways to draw in objects, and at last succeed
in some one way.  But it is surprising that an animal so low in the scale
as a worm should have the capacity for acting in this manner, as many
higher animals have no such capacity.  For instance, ants may be seen
vainly trying to drag an object transversely to their course, which could
be easily drawn longitudinally; though after a time they generally act in
a wiser manner, M. Fabre states {89a} that a Sphex—an insect belonging to
the same highly-endowed order with ants—stocks its nest with paralysed
grass-hoppers, which are invariably dragged into the burrow by their
antennæ.  When these were cut off close to the head, the Sphex seized the
palpi; but when these were likewise cut off, the attempt to drag its prey
into the burrow was given up in despair.  The Sphex had not intelligence
enough to seize one of the six legs or the ovipositor of the grasshopper,
which, as M. Fabre remarks, would have served equally well.  So again, if
the paralysed prey with an egg attached to it be taken out of the cell,
the Sphex after entering and finding the cell empty, nevertheless closes
it up in the usual elaborate manner.  Bees will try to escape and go on
buzzing for hours on a window, one half of which has been left open.
Even a pike continued during three months to dash and bruise itself
against the glass sides of an aquarium, in the vain attempt to seize
minnows on the opposite side. {89b}  A cobra-snake was seen by Mr. Layard
{90} to act much more wisely than either the pike or the Sphex; it had
swallowed a toad lying within a hole, and could not withdraw its head;
the toad was disgorged, and began to crawl away; it was again swallowed
and again disgorged; and now the snake had learnt by experience, for it
seized the toad by one of its legs and drew it out of the hole.  The
instincts of even the higher animals are often followed in a senseless or
purposeless manner: the weaver-bird will perseveringly wind threads
through the bars of its cage, as if building a nest: a squirrel will pat
nuts on a wooden floor, as if he had just buried them in the ground: a
beaver will cut up logs of wood and drag them about, though there is no
water to dam up; and so in many other cases.

Mr. Romanes, who has specially studied the minds of animals, believes
that we can safely infer intelligence, only when we see an individual
profiting by its own experience.  By this test the cobra showed some
intelligence; but this would have been much plainer if on a second
occasion he had drawn a toad out of a hole by its leg.  The Sphex failed
signally in this respect.  Now if worms try to drag objects into their
burrows first in one way and then in another, until they at last succeed,
they profit, at least in each particular instance, by experience.

But evidence has been advanced showing that worms do not habitually try
to draw objects into their burrows in many different ways.  Thus
half-decayed lime-leaves from their flexibility could have been drawn in
by their middle or basal parts, and were thus drawn into the burrows in
considerable numbers; yet a large majority were drawn in by or near the
apex.  The petioles of the Clematis could certainly have been drawn in
with equal ease by the base and apex; yet three times and in certain
cases five times as many were drawn in by the apex as by the base.  It
might have been thought that the foot-stalks of leaves would have tempted
the worms as a convenient handle; yet they are not largely used, except
when the base of the blade is narrower than the apex.  A large number of
the petioles of the ash are drawn in by the base; but this part serves
the worms as food.  In the case of pine-leaves worms plainly show that
they at least do not seize the leaf by chance; but their choice does not
appear to be determined by the divergence of the two needles, and the
consequent advantage or necessity of drawing them into their burrows by
the base.  With respect to the triangles of paper, those which had been
drawn in by the apex rarely had their bases creased or dirty; and this
shows that the worms had not often first tried to drag them in by this
end.

If worms are able to judge, either before drawing or after having drawn
an object close to the mouths of their burrows, how best to drag it in,
they must acquire some notion of its general shape.  This they probably
acquire by touching it in many places with the anterior extremity of
their bodies, which serves as a tactile organ.  It may be well to
remember how perfect the sense of touch becomes in a man when born blind
and deaf, as are worms.  If worms have the power of acquiring some
notion, however rude, of the shape of an object and of their burrows, as
seems to be the case, they deserve to be called intelligent; for they
then act in nearly the same manner as would a man under similar
circumstances.

To sum up, as chance does not determine the manner in which objects are
drawn into the burrows, and as the existence of specialized instincts for
each particular case cannot be admitted, the first and most natural
supposition is that worms try all methods until they at last succeed; but
many appearances are opposed to such a supposition.  One alternative
alone is left, namely, that worms, although standing low in the scale of
organization, possess some degree of intelligence.  This will strike
every one as very improbable; but it may be doubted whether we know
enough about the nervous system of the lower animals to justify our
natural distrust of such a conclusion.  With respect to the small size of
the cerebral ganglia, we should remember what a mass of inherited
knowledge, with some power of adapting means to an end, is crowded into
the minute brain of a worker-ant.

_Means by which worms excavate their burrows_.—This is effected in two
ways; by pushing away the earth on all sides, and by swallowing it.  In
the former case, the worm inserts the stretched out and attenuated
anterior extremity of its body into any little crevice, or hole; and
then, as Perrier remarks, {93} the pharynx is pushed forwards into this
part, which consequently swells and pushes away the earth on all sides.
The anterior extremity thus serves as a wedge.  It also serves, as we
have before seen, for prehension and suction, and as a tactile organ.  A
worm was placed on loose mould, and it buried itself in between two and
three minutes.  On another occasion four worms disappeared in 15 minutes
between the sides of the pot and the earth, which had been moderately
pressed down.  On a third occasion three large worms and a small one were
placed on loose mould well mixed with fine sand and firmly pressed down,
and they all disappeared, except the tail of one, in 35 minutes.  On a
fourth occasion six large worms were placed on argillaceous mud mixed
with sand firmly pressed down, and they disappeared, except the extreme
tips of the tails of two of them, in 40 minutes.  In none of these cases,
did the worms swallow, as far as could be seen, any earth.  They
generally entered the ground close to the sides of the pot.

A pot was next filled with very fine ferruginous sand, which was pressed
down, well watered, and thus rendered extremely compact.  A large worm
left on the surface did not succeed in penetrating it for some hours, and
did not bury itself completely until 25 hrs. 40 min. had elapsed.  This
was effected by the sand being swallowed, as was evident by the large
quantity ejected from the vent, long before the whole body had
disappeared.  Castings of a similar nature continued to be ejected from
the burrow during the whole of the following day.

As doubts have been expressed by some writers whether worms ever swallow
earth solely for the sake of making their burrows, some additional cases
may be given.  A mass of fine reddish sand, 23 inches in thickness, left
on the ground for nearly two years, had been penetrated in many places by
worms; and their castings consisted partly of the reddish sand and partly
of black earth brought up from beneath the mass.  This sand had been dug
up from a considerable depth, and was of so poor a nature that weeds
could not grow on it.  It is therefore highly improbable that it should
have been swallowed by the worms as food.  Again in a field near my house
the castings frequently consist of almost pure chalk, which lies at only
a little depth beneath the surface; and here again it is very improbable
that the chalk should have been swallowed for the sake of the very little
organic matter which could have percolated into it from the poor
overlying pasture.  Lastly, a casting thrown up through the concrete and
decayed mortar between the tiles, with which the now ruined aisle of
Beaulieu Abbey had formerly been paved, was washed, so that the coarser
matter alone was left.  This consisted of grains of quartz, micaceous
slate, other rocks, and bricks or tiles, many of them from 1/20 to 1/10
inch in diameter.  No one will suppose that these grains were swallowed
as food, yet they formed more than half of the casting, for they weighed
19 grains, the whole casting having weighed 33 grains.  Whenever a worm
burrows to a depth of some feet in undisturbed compact ground, it must
form its passage by swallowing the earth; for it is incredible that the
ground could yield on all sides to the pressure of the pharynx when
pushed forwards within the worm’s body.

That worms swallow a larger quantity of earth for the sake of extracting
any nutritious matter which it may contain than for making their burrows,
appears to me certain.  But as this old belief has been doubted by so
high an authority as Claparède, evidence in its favour must be given in
some detail.  There is no _à priori_ improbability in such a belief, for
besides other annelids, especially the _Arenicola marina_, which throws
up such a profusion of castings on our tidal sands, and which it is
believed thus subsists, there are animals belonging to the most distinct
classes, which do not burrow, but habitually swallow large quantities of
sand; namely, the molluscan Onchidium and many Echinoderms. {97}

If earth were swallowed only when worms deepened their burrows or made
new ones, castings would be thrown up only occasionally; but in many
places fresh castings may be seen every morning, and the amount of earth
ejected from the same burrow on successive days is large.  Yet worms do
not burrow to a great depth, except when the weather is very dry or
intensely cold.  On my lawn the black vegetable mould or humus is only
about 5 inches in thickness, and overlies light-coloured or reddish
clayey soil: now when castings are thrown up in the greatest profusion,
only a small proportion are light coloured, and it is incredible that the
worms should daily make fresh burrows in every direction in the thin
superficial layer of dark-coloured mould, unless they obtained nutriment
of some kind from it.  I have observed a strictly analogous case in a
field near my house where bright red clay lay close beneath the surface.
Again on one part of the Downs near Winchester the vegetable mould
overlying the chalk was found to be only from 3 to 4 inches in thickness;
and the many castings here ejected were as black as ink and did not
effervesce with acids; so that the worms must have confined themselves to
this thin superficial layer of mould, of which large quantities were
daily swallowed.  In another place at no great distance the castings were
white; and why the worms should have burrowed into the chalk in some
places and not in others, I am unable to conjecture.

Two great piles of leaves had been left to decay in my grounds, and
months after their removal, the bare surface, several yards in diameter,
was so thickly covered during several months with castings that they
formed an almost continuous layer; and the large number of worms which
lived here must have subsisted during these months on nutritious matter
contained in the black earth.

The lowest layer from another pile of decayed leaves mixed with some
earth was examined under a high power, and the number of spores of
various shapes and sizes which it contained was astonishingly great; and
these crushed in the gizzards of worms may largely aid in supporting
them.  Whenever castings are thrown up in the greatest number, few or no
leaves are drawn into the burrows; for instance the turf along a
hedgerow, about 200 yards in length, was daily observed in the autumn
during several weeks, and every morning many fresh castings were seen;
but not a single leaf was drawn into these burrows.  These castings from
their blackness and from the nature of the subsoil could not have been
brought up from a greater depth than 6 or 8 inches.  On what could these
worms have subsisted during this whole time, if not on matter contained
in the black earth?  On the other hand, whenever a large number of leaves
are drawn into the burrows, the worms seem to subsist chiefly on them,
for few earth-castings are then ejected on the surface.  This difference
in the behaviour of worms at different times, perhaps explains a
statement by Claparède, namely, that triturated leaves and earth are
always found in distinct parts of their intestines.

Worms sometimes abound in places where they can rarely or never obtain
dead or living leaves; for instance, beneath the pavement in well-swept
courtyards, into which leaves are only occasionally blown.  My son Horace
examined a house, one corner of which had subsided; and he found here in
the cellar, which was extremely damp, many small worm-castings thrown up
between the stones with which the cellar was paved; and in this case it
is improbable that the worms could ever have obtained leaves.  Mr. A. C.
Horner confirms this account, as he has seen castings in the cellars of
his house, which is an old one at Tonbridge.

But the best evidence, known to me, of worms subsisting for at least
considerable periods of time solely on the organic matter contained in
earth, is afforded by some facts communicated to me by Dr. King.  Near
Nice large castings abound in extraordinary numbers, so that 5 or 6 were
often found within the space of a square foot.  They consist of fine,
pale-coloured earth, containing calcareous matter, which after having
passed through the bodies of worms and being dried, coheres with
considerable force.  I have reason to believe that these castings had
been formed by species of Perichæta, which have been naturalized here
from the East. {101}  They rise like towers, with their summits often a
little broader than their bases, sometimes to a height of above 3 and
often to a height of 2½ inches.  The tallest of those which were measured
was 3.3 inches in height and 1 inch in diameter.  A small cylindrical
passage runs up the centre of each tower, through which the worm ascends
to eject the earth which it has swallowed, and thus to add to its height.
A structure of this kind would not allow leaves being easily dragged from
the surrounding ground into the burrows; and Dr. King, who looked
carefully, never saw even a fragment of a leaf thus drawn in.  Nor could
any trace be discovered of the worms having crawled down the exterior
surfaces of the towers in search of leaves; and had they done so, tracks
would almost certainly have been left on the upper part whilst it
remained soft.  It does not, however, follow that these worms do not draw
leaves into their burrows during some other season of the year, at which
time they would not build up their towers.

From the several foregoing cases, it can hardly be doubted that worms
swallow earth, not only for the sake of making their burrows, but for
obtaining food.  Hensen, however, concludes from his analyses of mould
that worms probably could not live on ordinary vegetable mould, though he
admits that they might be nourished to some extent by leaf-mould. {102}
But we have seen that worms eagerly devour raw meat, fat, and dead worms;
and ordinary mould can hardly fail to contain many ova, larvæ, and small
living or dead creatures, spores of cryptogamic plants, and micrococci,
such as those which give rise to saltpetre.  These various organisms,
together with some cellulose from any leaves and roots not utterly
decayed, might well account for such large quantities of mould being
swallowed by worms.  It may be worth while here to recall the fact that
certain species of Utricularia, which grow in damp places in the tropics,
possess bladders beautifully constructed for catching minute subterranean
animals; and these traps would not have been developed unless many small
animals inhabited such soil.

_The depth to which worms penetrate_, _and the construction of their
burrows_.—Although worms usually live near the surface, yet they burrow
to a considerable depth during long-continued dry weather and severe
cold.  In Scandinavia, according to Eisen, and in Scotland, according to
Mr. Lindsay Carnagie, the burrows run down to a depth of from 7 to 8
feet; in North Germany, according to Hoffmeister, from 6 to 8 feet, but
Hensen says, from 3 to 6 feet.  This latter observer has seen worms
frozen at a depth of 1½ feet beneath the surface.  I have not myself had
many opportunities for observation, but I have often met with worms at
depths of 3 to 4 feet.  In a bed of fine sand overlying the chalk, which
had never been disturbed, a worm was cut into two at 55 inches, and
another was found here at Down in December at the bottom of its burrow,
at 61 inches beneath the surface.  Lastly, in earth near an old Roman
Villa, which had not been disturbed for many centuries, a worm was met
with at a depth of 66 inches; and this was in the middle of August.

The burrows run down perpendicularly, or more commonly a little
obliquely.  They are said sometimes to branch, but as far as I have seen
this does not occur, except in recently dug ground and near the surface.
They are generally, or as I believe invariably, lined with a thin layer
of fine, dark-coloured earth voided by the worms; so that they must at
first be made a little wider than their ultimate diameter.  I have seen
several burrows in undisturbed sand thus lined at a depth of 4 ft. 6 in.;
and others close to the surface thus lined in recently dug ground.  The
walls of fresh burrows are often dotted with little globular pellets of
voided earth, still soft and viscid; and these, as it appears, are spread
out on all sides by the worm as it travels up or down its burrow.  The
lining thus formed becomes very compact and smooth when nearly dry, and
closely fits the worm’s body.  The minute reflexed bristles which project
in rows on all sides from the body, thus have excellent points of
support; and the burrow is rendered well adapted for the rapid movement
of the animal.  The lining appears also to strengthen the walls, and
perhaps saves the worm’s body from being scratched.  I think so because
several burrows which passed through a layer of sifted coal-cinders,
spread over turf to a thickness of 1½ inch, had been thus lined to an
unusual thickness.  In this case the worms, judging from the castings,
had pushed the cinders away on all sides and had not swallowed any of
them.  In another place, burrows similarly lined, passed through a layer
of coarse coal-cinders, 3½ inches in thickness.  We thus see that the
burrows are not mere excavations, but may rather be compared with tunnels
lined with cement.

The mouths of the burrow are in addition often lined with leaves; and
this is an instinct distinct from that of plugging them up, and does not
appear to have been hitherto noticed.  Many leaves of the Scotch-fir or
pine (_Pinus sylvestris_) were given to worms kept in confinement in two
pots; and when after several weeks the earth was carefully broken up, the
upper parts of three oblique burrows were found surrounded for lengths of
7, 4, and 3½ inches with pine-leaves, together with fragments of other
leaves which had been given the worms as food.  Glass beads and bits of
tile, which had been strewed on the surface of the soil, were stuck into
the interstices between the pine-leaves; and these interstices were
likewise plastered with the viscid castings voided by the worms.  The
structures thus formed cohered so well, that I succeeded in removing one
with only a little earth adhering to it.  It consisted of a slightly
curved cylindrical case, the interior of which could be seen through
holes in the sides and at either end.  The pine-leaves had all been drawn
in by their bases; and the sharp points of the needles had been pressed
into the lining of voided earth.  Had this not been effectually done, the
sharp points would have prevented the retreat of the worms into their
burrows; and these structures would have resembled traps armed with
converging points of wire, rendering the ingress of an animal easy and
its egress difficult or impossible.  The skill shown by these worms is
noteworthy and is the more remarkable, as the Scotch pine is not a native
of this district.

After having examined these burrows made by worms in confinement, I
looked at those in a flower-bed near some Scotch pines.  These had all
been plugged up in the ordinary manner with the leaves of this tree,
drawn in for a length of from 1 to 1½ inch; but the mouths of many of
them were likewise lined with them, mingled with fragments of other kinds
of leaves, drawn in to a depth of 4 or 5 inches.  Worms often remain, as
formerly stated, for a long time close to the mouths of their burrows,
apparently for warmth; and the basket-like structures formed of leaves
would keep their bodies from coming into close contact with the cold damp
earth.  That they habitually rested on the pine-leaves, was rendered
probable by their clean and almost polished surfaces.

The burrows which run far down into the ground, generally, or at least
often, terminate in a little enlargement or chamber.  Here, according to
Hoffmeister, one or several worms pass the winter rolled up into a ball.
Mr. Lindsay Carnagie informed me (1838) that he had examined many burrows
over a stone-quarry in Scotland, where the overlying boulder-clay and
mould had recently been cleared away, and a little vertical cliff thus
left.  In several cases the same burrow was a little enlarged at two or
three points one beneath the other; and all the burrows terminated in a
rather large chamber, at a depth of 7 or 8 feet from the surface.  These
chambers contained many small sharp bits of stone and husks of
flax-seeds.  They must also have contained living seeds, for on the
following spring Mr. Carnagie saw grass-plants sprouting out of some of
the intersected chambers.  I found at Abinger in Surrey two burrows
terminating in similar chambers at a depth of 36 and 41 inches, and these
were lined or paved with little pebbles, about as large as mustard seeds;
and in one of the chambers there was a decayed oat-grain, with its husk.
Hensen likewise states that the bottoms of the burrows are lined with
little stones; and where these could not be procured, seeds, apparently
of the pear, had been used, as many as fifteen having been carried down
into a single burrow, one of which had germinated. {108}  We thus see how
easily a botanist might be deceived who wished to learn how long deeply
buried seeds remained alive, if he were to collect earth from a
considerable depth, on the supposition that it could contain only seeds
which had long lain buried.  It is probable that the little stones, as
well as the seeds, are carried down from the surface by being swallowed;
for a surprising number of glass beads, bits of tile and of glass were
certainly thus carried down by worms kept in pots; but some may have been
carried down within their mouths.  The sole conjecture which I can form
why worms line their winter-quarters with little stones and seeds, is to
prevent their closely coiled-up bodies from coming into close contact
with the surrounding cold soil; and such contact would perhaps interfere
with their respiration which is effected by the skin alone.

A worm after swallowing earth, whether for making its burrow or for food,
soon comes to the surface to empty its body.  The ejected earth is
thoroughly mingled with the intestinal secretions, and is thus rendered
viscid.  After being dried it sets hard.  I have watched worms during the
act of ejection, and when the earth was in a very liquid state it was
ejected in little spurts, and by a slow peristaltic movement when not so
liquid.  It is not cast indifferently on any side, but with some care,
first on one and then on another side; the tail being used almost like a
trowel.  When a worm comes to the surface to eject earth, the tail
protrudes, but when it collects leaves its head must protrude.  Worms
therefore must have the power of turning round in their closely-fitting
burrows; and this, as it appears to us, would be a difficult feat.  As
soon as a little heap has been formed, the worm apparently avoids, for
the sake of safety, protruding its tail; and the earthy matter is forced
up through the previously deposited soft mass.  The mouth of the same
burrow is used for this purpose for a considerable time.  In the case of
the tower-like castings (see Fig. 2) near Nice, and of the similar but
still taller towers from Bengal (hereafter to be described and figured),
a considerable degree of skill is exhibited in their construction.  Dr.
King also observed that the passage up these towers hardly ever ran in
the same exact line with the underlying burrow, so that a thin
cylindrical object such as a haulm of grass, could not be passed down the
tower into the burrow; and this change of direction probably serves in
some manner as a protection.

Worms do not always eject their castings on the surface of the ground.
When they can find any cavity, as when burrowing in newly turned-up
earth, or between the stems of banked-up plants, they deposit their
castings in such places.  So again any hollow beneath a large stone lying
on the surface of the ground, is soon filled up with their castings.
According to Hensen, old burrows are habitually used for this purpose;
but as far as my experience serves, this is not the case, excepting with
those near the surface in recently dug ground.  I think that Hensen may
have been deceived by the walls of old burrows, lined with black earth,
having sunk in or collapsed; for black streaks are thus left, and these
are conspicuous when passing through light-coloured soil, and might be
mistaken for completely filled-up burrows.

It is certain that old burrows collapse in the course of time; for as we
shall see in the next chapter, the fine earth voided by worms, if spread
out uniformly, would form in many places in the course of a year a layer
0.2 of an inch in thickness; so that at any rate this large amount is not
deposited within the old unused burrows.  If the burrows did not
collapse, the whole ground would be first thickly riddled with holes to a
depth of about ten inches, and in fifty years a hollow unsupported space,
ten inches in depth, would be left.  The holes left by the decay of
successively formed roots of trees and plants must likewise collapse in
the course of time.

The burrows of worms run down perpendicularly or a little obliquely, and
where the soil is at all argillaceous, there is no difficulty in
believing that the walls would slowly flow or slide inwards during very
wet weather.  When, however, the soil is sandy or mingled with many small
stones, it can hardly be viscous enough to flow inwards during even the
wettest weather; but another agency may here come into play.  After much
rain the ground swells, and as it cannot expand laterally, the surface
rises; during dry weather it sinks again.  For instance, a large flat
stone laid on the surface of a field sank 3.33 mm. whilst the weather was
dry between May 9th and June 13th, and rose 1.91 mm, between September
7th and 19th of the same year, much rain having fallen during the latter
part of this time.  During frosts and thaws the movements were twice as
great.  These observations were made by my son Horace, who will hereafter
publish an account of the movements of this stone during successive wet
and dry seasons, and of the effects of its being undermined by worms.
Now when the ground swells, if it be penetrated by cylindrical holes,
such as worm-burrows, their walls will tend to yield and be pressed
inwards; and the yielding will be greater in the deeper parts (supposing
the whole to be equally moistened) from the greater weight of the
superincumbent soil which has to be raised, than in the parts near the
surface.  When the ground dries, the walls will shrink a little and the
burrows will be a little enlarged.  Their enlargement, however, through
the lateral contraction of the ground, will not be favoured, but rather
opposed, by the weight of the superincumbent soil.

_Distribution of Worms_.—Earth-worms are found in all parts of the world,
and some of the genera have an enormous range. {113}  They inhabit the
most isolated islands; they abound in Iceland, and are known to exist in
the West Indies, St. Helena, Madagascar, New Caledonia and Tahiti.  In
the Antarctic regions, worms from Kerguelen Land have been described by
Ray Lankester; and I found them in the Falkland Islands.  How they reach
such isolated islands is at present quite unknown.  They are easily
killed by salt-water, and it does not appear probable that young worms or
their egg-capsules could be carried in earth adhering to the feet or
beaks of land-birds.  Moreover Kerguelen Land is not now inhabited by any
land-bird.

In this volume we are chiefly concerned with the earth cast up by worms,
and I have gleaned a few facts on this subject with respect to distant
lands.  Worms throw up plenty of castings in the United States.  In
Venezuela, castings, probably ejected by species of Urochæta, are common
in the gardens and fields, but not in the forests, as I hear from Dr.
Ernst of Caracas.  He collected 156 castings from the court-yard of his
house, having an area of 200 square yards.  They varied in bulk from half
a cubic centimeter to five cubic centimeters, and were on an average
three cubic centimeters.  They were, therefore, of small size in
comparison with those often found in England; for six large castings from
a field near my house averaged 16 cubic centimeters.  Several species of
earth-worms are common in St. Catharina in South Brazil, and Fritz Müller
informs me “that in most parts of the forests and pasture-lands, the
whole soil, to a depth of a quarter of a metre, looks as if it had passed
repeatedly through the intestines of earth-worms, even where hardly any
castings are to be seen on the surface.”  A gigantic but very rare
species is found there, the burrows of which are sometimes even two
centimeters or nearly 0.8 of an inch in diameter, and which apparently
penetrate the ground to a great depth.

In the dry climate of New South Wales, I hardly expected that worms would
be common; but Dr. G. Krefft of Sydney, to whom I applied, after making
inquiries from gardeners and others, and from his own observations,
informs me that their castings abound.  He sent me some collected after
heavy rain, and they consisted of little pellets, about 0.15 inch in
diameter; and the blackened sandy earth of which they were formed still
cohered with considerable tenacity.

The late Mr. John Scott of the Botanic Gardens near Calcutta made many
observations for me on worms living under the hot and humid climate of
Bengal.  The castings abound almost everywhere, in jungles and in the
open ground, to a greater degree, as he thinks, than in England.  After
the water has subsided from the flooded rice-fields, the whole surface
very soon becomes studded with castings—a fact which much surprised Mr.
Scott, as he did not know how long worms could survive beneath water.
They cause much trouble in the Botanic garden, “for some of the finest of
our lawns can be kept in anything like order only by being almost daily
rolled; if left undisturbed for a few days they become studded with large
castings.”  These closely resemble those described as abounding near
Nice; and they are probably the work of a species of Perichæta.  They
stand up like towers, with an open passage in the centre.

   [Picture: Fig. 3: A tower-like casting.  Fig. 4: A casting from the
                            Nilgiri Mountains]

A figure of one of these castings from a photograph is here given (Fig.
3).  The largest received by me was 3½ inches in height and 1.35 inch in
diameter; another was only ¾ inch in diameter and 2¾ in height.  In the
following year, Mr. Scott measured several of the largest; one was 6
inches in height and nearly 1½ in diameter: two others were 5 inches in
height and respectively 2 and rather more than 2½ inches in diameter.
The average weight of the 22 castings sent to me was 35 grammes (1¼ oz.);
and one of them weighed 44.8 grammes (or 2 oz.). All these castings were
thrown up either in one night or in two.  Where the ground in Bengal is
dry, as under large trees, castings of a different kind are found in vast
numbers: these consist of little oval or conical bodies, from about the
1/20 to rather above 1/10 of an inch in length.  They are obviously
voided by a distinct species of worms.

The period during which worms near Calcutta display such extraordinary
activity lasts for only a little over two months, namely, during the cool
season after the rains.  At this time they are generally found within
about 10 inches beneath the surface.  During the hot season they burrow
to a greater depth, and are then found coiled up and apparently
hybernating.  Mr. Scott has never seen them at a greater depth than 2½
feet, but has heard of their having been found at 4 feet.  Within the
forests, fresh castings may be found even during the hot season.  The
worms in the Botanic garden, during the cool and dry season, draw many
leaves and little sticks into the mouths of their burrows, like our
English worms; but they rarely act in this manner during the rainy
season.

Mr. Scott saw worm-castings on the lofty mountains of Sikkim in North
India.  In South India Dr. King found in one place, on the plateau of the
Nilgiris, at an elevation of 7000 feet, “a good many castings,” which are
interesting for their great size.  The worms which eject them are seen
only during the wet season, and are reported to be from 12 to 15 inches
in length, and as thick as a man’s little finger.  These castings were
collected by Dr. King after a period of 110 days without any rain; and
they must have been ejected either during the north-east or more probably
during the previous south-west monsoon; for their surfaces had suffered
some disintegration and they were penetrated by many fine roots.  A
drawing is here given (Fig. 4) of one which seems to have best retained
its original size and appearance.  Notwithstanding some loss from
disintegration, five of the largest of these castings (after having been
well sun-dried) weighed each on an average 89.5 grammes, or above 3 oz.;
and the largest weighed 123.14 grammes, or 4? oz.,—that is, above a
quarter of a pound!  The largest convolutions were rather more than one
inch in diameter; but it is probable that they had subsided a little
whilst soft, and that their diameters had thus been increased.  Some had
flowed so much that they now consisted of a pile of almost flat confluent
cakes.  All were formed of fine, rather light-coloured earth, and were
surprisingly hard and compact, owing no doubt to the animal matter by
which the particles of earth had been cemented together.  They did not
disintegrate, even when left for some hours in water.  Although they had
been cast up on the surface of gravelly soil, they contained extremely
few bits of rock, the largest of which was only 0.15 inch in diameter.

Dr. King saw in Ceylon a worm about 2 feet in length and ½ inch in
diameter; and he was told that it was a very common species during the
wet season.  These worms must throw up castings at least as large as
those on the Nilgiri Mountains; but Dr. King saw none during his short
visit to Ceylon.

Sufficient facts have now been given, showing that worms do much work in
bringing up fine earth to the surface in most or all parts of the world,
and under the most different climates.




CHAPTER III.
THE AMOUNT OF FINE EARTH BROUGHT UP BY WORMS TO THE SURFACE.


Rate at which various objects strewed on the surface of grass-fields are
covered up by the castings of worms—The burial of a paved path—The slow
subsidence of great stones left on the surface—The number of worms which
live within a given space—The weight of earth ejected from a burrow, and
from all the burrows within a given space—The thickness of the layer of
mould which the castings on a given space would form within a given time
if uniformly spread out—The slow rate at which mould can increase to a
great thickness—Conclusion.

WE now come to the more immediate subject of this volume, namely, the
amount of earth which is brought up by worms from beneath the surface,
and is afterwards spread out more or less completely by the rain and
wind.  The amount can be judged of by two methods,—by the rate at which
objects left on the surface are buried, and more accurately by weighing
the quantity brought up within a given time.  We will begin with the
first method, as it was first followed.

Near Mael Hall in Staffordshire, quick-lime had been spread about the
year 1827 thickly over a field of good pasture-land, which had not since
been ploughed.  Some square holes were dug in this field in the beginning
of October 1837; and the sections showed a layer of turf, formed by the
matted roots of the grasses, ½ inch in thickness, beneath which, at a
depth of 2½ inches (or 3 inches from the surface), a layer of the lime in
powder or in small lumps could be distinctly seen running all round the
vertical sides of the holes.  The soil beneath the layer of lime was
either gravelly or of a coarse sandy nature, and differed considerably in
appearance from the overlying dark-coloured fine mould.  Coal-cinders had
been spread over a part of this same field either in the year 1833 or
1834; and when the above holes were dug, that is after an interval of 3
or 4 years, the cinders formed a line of black spots round the holes, at
a depth of 1 inch beneath the surface, parallel to and above the white
layer of lime.  Over another part of this field cinders had been strewed,
only about half-a-year before, and these either still lay on the surface
or were entangled among the roots of the grasses; and I here saw the
commencement of the burying process, for worm-castings had been heaped on
several of the smaller fragments.  After an interval of 4¾ years this
field was re-examined, and now the two layers of lime and cinders were
found almost everywhere at a greater depth than before by nearly 1 inch,
we will say by ¾ of an inch.  Therefore mould to an average thickness of
0.22 of an inch had been annually brought up by the worms, and had been
spread over the surface of this field.

Coal-cinders had been strewed over another field, at a date which could
not be positively ascertained, so thickly that they formed (October,
1837) a layer, 1 inch in thickness at a depth of about 3 inches from the
surface.  The layer was so continuous that the over-lying dark vegetable
mould was connected with the sub-soil of red clay only by the roots of
the grasses; and when these were broken, the mould and the red clay fell
apart.  In a third field, on which coal-cinders and burnt marl had been
strewed several times at unknown dates, holes were dug in 1842; and a
layer of cinders could be traced at a depth of 3½ inches, beneath which
at a depth of 9½ inches from the surface there was a line of cinders
together with burnt marl.  On the sides of one hole there were two layers
of cinders, at 2 and 3½ inches beneath the surface; and below them at a
depth in parts of 9½, and in other parts of 10½ inches there were
fragments of burnt marl.  In a fourth field two layers of lime, one above
the other, could be distinctly traced, and beneath them a layer of
cinders and burnt marl at a depth of from 10 to 12 inches below the
surface.

  [Picture: Fig. 5: Section of the vegetable mould in a field.  Fig. 6:
                  Traverse section across a large stone]

A piece of waste, swampy land was enclosed, drained, ploughed, harrowed
and thickly covered in the year 1822 with burnt marl and cinders.  It was
sowed with grass seeds, and now supports a tolerably good but coarse
pasture.  Holes were dug in this field in 1837, or 15 years after its
reclamation, and we see in the accompanying diagram (Fig. 5), reduced to
half of the natural scale, that the turf was ½ inch thick, beneath which
there was a layer of vegetable mould 2½ inches thick.  This layer did not
contain fragments of any kind; but beneath it there was a layer of mould,
1½ inch in thickness, full of fragments of burnt marl, conspicuous from
their red colour, one of which near the bottom was an inch in length; and
other fragments of coal-cinders together with a few white quartz pebbles.
Beneath this layer and at a depth of 4½ inches from the surface, the
original black, peaty, sandy soil with a few quartz pebbles was
encountered.  Here therefore the fragments of burnt marl and cinders had
been covered in the course of 15 years by a layer of fine vegetable
mould, only 2½ inches in thickness, excluding the turf.  Six and a half
years subsequently this field was re-examined, and the fragments were now
found at from 4 to 5 inches beneath the surface.  So that in this
interval of 6½ years, about 1½ inch of mould had been added to the
superficial layer.  I am surprised that a greater quantity had not been
brought up during the whole 21½ years, for in the closely underlying
black, peaty soil there were many worms.  It is, however, probable that
formerly, whilst the land remained poor, worms were scanty; and the mould
would then have accumulated slowly.  The average annual increase of
thickness for the whole period is 0.19 of an inch.

Two other cases are worth recording.  In the spring of 1835, a field,
which had long existed as poor pasture and was so swampy that it trembled
slightly when stamped on, was thickly covered with red sand so that the
whole surface appeared at first bright red.  When holes were dug in this
field after an interval of about 2½ years, the sand formed a layer at a
depth of ¾ in. beneath the surface.  In 1842 (i.e., 7 years after the
sand had been laid on) fresh holes were dug, and now the red sand formed
a distinct layer, 2 inches beneath the surface, or 1½ inch beneath the
turf; so that on an average, 0.21 inch of mould had been annually brought
to the surface.  Immediately beneath the layer of red sand, the original
substratum of black sandy peat extended.

A grass field, likewise not far from Maer Hall, had formerly been thickly
covered with marl, and was then left for several years as pasture; it was
afterwards ploughed.  A friend had three trenches dug in this field 28
years after the application of the marl, {126} and a layer of the marl
fragments could be traced at a depth, carefully measured, of 12 inches in
some parts, and of 14 inches in other parts.  This difference in depth
depended on the layer being horizontal, whilst the surface consisted of
ridges and furrows from the field having been ploughed.  The tenant
assured me that it had never been turned up to a greater depth than from
6 to 8 inches; and as the fragments formed an unbroken horizontal layer
from 12 to 14 inches beneath the surface, these must have been buried by
the worms whilst the land was in pasture before it was ploughed, for
otherwise they would have been indiscriminately scattered by the plough
throughout the whole thickness of the soil.  Four-and-a-half years
afterwards I had three holes dug in this field, in which potatoes had
been lately planted, and the layer of marl-fragments was now found 13
inches beneath the bottoms of the furrows, and therefore probably 15
inches beneath the general level of the field.  It should, however, be
observed that the thickness of the blackish sandy soil, which had been
thrown up by the worms above the marl-fragments in the course of 32½
years, would have measured less than 15 inches, if the field had always
remained as pasture, for the soil would in this case have been much more
compact.  The fragments of marl almost rested on an undisturbed
substratum of white sand with quartz pebbles; and as this would be little
attractive to worms, the mould would hereafter be very slowly increased
by their action.

We will now give some cases of the action of worms, on land differing
widely from the dry sandy or the swampy pastures just described.  The
chalk formation extends all round my house in Kent; and its surface, from
having been exposed during an immense period to the dissolving action of
rain-water, is extremely irregular, being abruptly festooned and
penetrated by many deep well-like cavities. {128}  During the dissolution
of the chalk, the insoluble matter, including a vast number of unrolled
flints of all sizes, has been left on the surface and forms a bed of
stiff red clay, full of flints, and generally from 6 to 14 feet in
thickness.  Over the red clay, wherever the land has long remained as
pasture, there is a layer a few inches in thickness, of dark-coloured
vegetable mould.

A quantity of broken chalk was spread, on December 20, 1842, over a part
of a field near my house, which had existed as pasture certainly for 30,
probably for twice or thrice as many years.  The chalk was laid on the
land for the sake of observing at some future period to what depth it
would become buried.  At the end of November, 1871, that is after an
interval of 29 years, a trench was dug across this part of the field; and
a line of white nodules could be traced on both sides of the trench, at a
depth of 7 inches from the surface.  The mould, therefore, (excluding the
turf) had here been thrown up at an average rate of 0.22 inch per year.
Beneath the line of chalk nodules there was in parts hardly any fine
earth free of flints, while in other parts there was a layer, 2¼ inches
in thickness.  In this latter case the mould was altogether 9¼ inches
thick; and in one such spot a nodule of chalk and a smooth flint pebble,
both of which must have been left at some former time on the surface,
were found at this depth.  At from 11 to 12 inches beneath the surface,
the undisturbed reddish clay, full of flints, extended.  The appearance
of the above nodules of chalk surprised me, much at first, as they
closely resembled water-worn pebbles, whereas the freshly-broken
fragments had been angular.  But on examining the nodules with a lens,
they no longer appeared water-worn, for their surfaces were pitted
through unequal corrosion, and minute, sharp points, formed of broken
fossil shells, projected from them.  It was evident that the corners of
the original fragments of chalk had been wholly dissolved, from
presenting a large surface to the carbonic acid dissolved in the
rain-water and to that generated in soil containing vegetable matter, as
well as to the humus-acids. {131}  The projecting corners would also,
relatively to the other parts, have been embraced by a larger number of
living rootlets; and these have the power of even attacking marble, as
Sachs has shown.  Thus, in the course of 29 years, buried angular
fragments of chalk had been converted into well-rounded nodules.

Another part of this same field was mossy, and as it was thought that
sifted coal-cinders would improve the pasture, a thick layer was spread
over this part either in 1842 or 1843, and another layer some years
afterwards.  In 1871 a trench was here dug, and many cinders lay in a
line at a depth of 7 inches beneath the surface, with another line at a
depth of 5½ inches parallel to the one beneath.  In another part of this
field, which had formerly existed as a separate one, and which it was
believed had been pasture-land for more than a century, trenches were dug
to see how thick the vegetable mould was.  By chance the first trench was
made at a spot where at some former period, certainly more than forty
years before, a large hole had been filled up with coarse red clay,
flints, fragments of chalk, and gravel; and here the fine vegetable mould
was only from 4? to 4? inches in thickness.  In another and undisturbed
place, the mould varied much in thickness, namely, from 6½ to 8½ inches;
beneath which a few small fragments of brick were found in one place.
From these several cases, it would appear that during the last 29 years
mould has been heaped on the surface at an average annual rate of from
0.2 to 0.22 of an inch.  But in this district when a ploughed field is
first laid down in grass, the mould accumulates at a much slower rate.
The rate, also, must become very much slower after a bed of mould,
several inches in thickness, has been formed; for the worms then live
chiefly near the surface, and burrow down to a greater depth so as to
bring up fresh earth from below, only during the winter when the weather
is very cold (at which time worms were found in this field at a depth of
26 inches) and during summer, when the weather is very dry.

A field, which adjoins the one just described, slopes in one part rather
steeply (viz., at from 10° to 15°); this part was last ploughed in 1841,
was then harrowed and left to become pasture-land.  For several years it
was clothed with an extremely scant vegetation, and was so thickly
covered with small and large flints (some of them half as large as a
child’s head) that the field was always called by my sons “the stony
field.”  When they ran down the slope the stones clattered together, I
remember doubting whether I should live to see these larger flints
covered with vegetable mould and turf.  But the smaller stones
disappeared before many years had elapsed, as did every one of the larger
ones after a time; so that after thirty years (1871) a horse could gallop
over the compact turf from one end of the field to the other, and not
strike a single stone with his shoes.  To anyone who remembered the
appearance of the field in 1842, the transformation was wonderful.  This
was certainly the work of the worms, for though castings were not
frequent for several years, yet some were thrown up month after month,
and these gradually increased in numbers as the pasture improved.  In the
year 1871 a trench was dug on the above slope, and the blades of grass
were cut off close to the roots, so that the thickness of the turf and of
the vegetable mould could be measured accurately.  The turf was rather
less than half an inch, and the mould, which did not contain any stones,
2½ inches in thickness.  Beneath this lay coarse clayey earth full of
flints, like that in any of the neighbouring ploughed fields.  This
coarse earth easily fell apart from the overlying mould when a spit was
lifted up.  The average rate of accumulation of the mould during the
whole thirty years was only .083 inch per year (i.e., nearly one inch in
twelve years); but the rate must have been much slower at first, and
afterwards considerably quicker.

The transformation in the appearance of this field, which had been
effected beneath my eyes, was afterwards rendered the more striking, when
I examined in Knole Park a dense forest of lofty beech-trees, beneath
which nothing grew.  Here the ground was thickly strewed with large naked
stones, and worm-castings were almost wholly absent.  Obscure lines and
irregularities on the surface indicated that the land had been cultivated
some centuries ago.  It is probable that a thick wood of young
beech-trees sprung up so quickly, that time enough was not allowed for
worms to cover up the stones with their castings, before the site became
unfitted for their existence.  Anyhow the contrast between the state of
the now miscalled “stony field,” well stocked with worms, and the present
state of the ground beneath the old beech-trees in Knole Park, where
worms appeared to be absent, was striking.

A narrow path running across part of my lawn was paved in 1843 with small
flagstones, set edgeways; but worms threw up many castings and weeds grew
thickly between them.  During several years the path was weeded and
swept; but ultimately the weeds and worms prevailed, and the gardener
ceased to sweep, merely mowing off the weeds, as often as the lawn was
mowed.  The path soon became almost covered up, and after several years
no trace of it was left.  On removing, in 1877, the thin overlying layer
of turf, the small flag-stones, all in their proper places, were found
covered by an inch of fine mould.

Two recently published accounts of substances strewed on the surface of
pasture-land, having become buried through the action of worms, may be
here noticed.  The Rev. H. C. Key had a ditch cut in a field, over which
coal-ashes had been spread, as it was believed, eighteen years before;
and on the clean-cut perpendicular sides of the ditch, at a depth of at
least seven inches, there could be seen, for a length of 60 yards, “a
distinct, very even, narrow line of coal-ashes, mixed with small coal,
perfectly parallel with the top-sward.” {136a}  This parallelism and the
length of the section give interest to the case.  Secondly, Mr. Dancer
states {136b} that crushed bones had been thickly strewed over a field;
and “some years afterwards” these were found “several inches below the
surface, at a uniform depth.”

The Rev. Mr. Zincke informs me that he has lately had an orchard dug to
the unusual depth of 4 feet.  The upper 18 inches consisted of
dark-coloured vegetable mould, and the next 18 inches of sandy loam,
containing in the lower part many rolled pieces of sandstone, with some
bits of brick and tile, probably of Roman origin, as remains of this
period have been found close by.  The sandy loam rested on an indurated
ferruginous pan of yellow clay, on the surface of which two perfect celts
were found.  If, as seems probable, the celts were originally left on the
surface of the land, they have since been covered up with earth 3 feet in
thickness, all of which has probably passed through the bodies of worms,
excepting the stones which may have been scattered on the surface at
different times, together with manure or by other means.  It is difficult
otherwise to understand the source of the 18 inches of sandy loam, which
differed from the overlying dark vegetable mould, after both had been
burnt, only in being of a brighter red colour, and in not being quite so
fine-grained.  But on this view we must suppose that the carbon in
vegetable mould, when it lies at some little depth beneath the surface
and does not continually receive decaying vegetable matter from above,
loses its dark colour in the course of centuries; but whether this is
probable I do not know.

Worms appear to act in the same manner in New Zealand as in Europe; for
Professor J. von Haast has described {138a} a section near the coast,
consisting of mica-schist, “covered by 5 or 6 feet of loess, above which
about 12 inches of vegetable soil had accumulated.”  Between the loess
and the mould there was a layer from 3 to 6 inches in thickness,
consisting of “cores, implements, flakes, and chips, all manufactured
from hard basaltic rock.”  It is therefore probable that the aborigines,
at some former period, had left these objects on the surface, and that
they had afterwards been slowly covered up by the castings of worms.

Farmers in England are well aware that objects of all kinds, left on the
surface of pasture-land, after a time disappear, or, as they say, work
themselves downwards.  How powdered lime, cinders, and heavy stones, can
work down, and at the same rate, through the matted roots of a
grass-covered surface, is a question which has probably never occurred to
them. {138b}

_The Sinking of great Stones through the Action of Worms_.—When a stone
of large size and of irregular shape is left on the surface of the
ground, it rests, of course, on the more protuberant parts; but worms
soon fill up with their castings all the hollow spaces on the lower side;
for, as Hensen remarks, they like the shelter of stones.  As soon as the
hollows are filled up, the worms eject the earth which they have
swallowed beyond the circumference of the stones; and thus the surface of
the ground is raised all round the stone.  As the burrows excavated
directly beneath the stone after a time collapse, the stone sinks a
little. {139}  Hence it is, that boulders which at some ancient period
have rolled down from a rocky mountain or cliff on to a meadow at its
base, are always somewhat imbedded in the soil; and, when removed, leave
an exact impression of their lower surfaces in the underlying fine mould.
If, however, a boulder is of such huge dimensions, that the earth beneath
is kept dry, such earth will not be inhabited by worms, and the boulder
will not sink into the ground.

A lime-kiln formerly stood in a grass-field near Leith Hill Place in
Surrey, and was pulled down 35 years before my visit; all the loose
rubbish had been carted away, excepting three large stones of quartzose
sandstone, which it was thought might hereafter be of some use.  An old
workman remembered that they had been left on a bare surface of broken
bricks and mortar, close to the foundations of the kiln; but the whole
surrounding surface is now covered with turf and mould.  The two largest
of these stones had never since been moved; nor could this easily have
been done, as, when I had them removed, it was the work of two men with
levers.  One of these stones, and not the largest, was 64 inches long, 17
inches broad, and from 9 to 10 inches in thickness.  Its lower surface
was somewhat protuberant in the middle; and this part still rested on
broken bricks and mortar, showing the truth of the old workman’s account.
Beneath the brick rubbish the natural sandy soil, full of fragments of
sandstone was found; and this could have yielded very little, if at all,
to the weight of the stone, as might have been expected if the sub-soil
had been clay.  The surface of the field, for a distance of about 9
inches round the stone, gradually sloped up to it, and close to the stone
stood in most places about 4 inches above the surrounding ground.  The
base of the stone was buried from 1 to 2 inches beneath the general
level, and the upper surface projected about 8 inches above this level,
or about 4 inches above the sloping border of turf.  After the removal of
the stone it became evident that one of its pointed ends must at first
have stood clear above the ground by some inches, but its upper surface
was now on a level with the surrounding turf.  When the stone was
removed, an exact cast of its lower side, forming a shallow crateriform
hollow, was left, the inner surface of which consisted of fine black
mould, excepting where the more protuberant parts rested on the
brick-rubbish.  A transverse section of this stone, together with its
bed, drawn from measurements made after it had been displaced, is here
given on a scale of ½ inch to a foot (Fig. 6).  The turf-covered border
which sloped up to the stone, consisted of fine vegetable mould, in one
part 7 inches in thickness.  This evidently consisted of worm-castings,
several of which had been recently ejected.  The whole stone had sunk in
the thirty-five years, as far as I could judge, about 1½ inch; and this
must have been due to the brick-rubbish beneath the more protuberant
parts having been undermined by worms.  At this rate the upper surface of
the stone, if it had been left undisturbed, would have sunk to the
general level of the field in 247 years; but before this could have
occurred, some earth would have been washed down by heavy rain from the
castings on the raised border of turf over the upper surface of the
stone.

The second stone was larger that the one just described, viz., 67 inches
in length, 39 in breadth, and 15 in thickness.  The lower surface was
nearly flat, so that the worms must soon have been compelled to eject
their castings beyond its circumference.  The stone as a whole had sunk
about 2 inches into the ground.  At this rate it would have required 262
years for its upper surface to have sunk to the general level of the
field.  The upwardly sloping, turf-covered border round the stone was
broader than in the last case, viz., from 14 to 16 inches; and why this
should be so, I could see no reason.  In most parts this border was not
so high as in the last case, viz., from 2 to 2½ inches, but in one place
it was as much as 5½.  Its average height close to the stone was probably
about 3 inches, and it thinned out to nothing.  If so, a layer of fine
earth, 15 inches in breadth and 1½ inch in average thickness, of
sufficient length to surround the whole of the much elongated slab, must
have been brought up by the worms in chief part from beneath the stone in
the course of 35 years.  This amount would be amply sufficient to account
for its having sunk about 2 inches into the ground; more especially if we
bear in mind that a good deal of the finest earth would have been washed
by heavy rain from the castings ejected on the sloping border down to the
level of the field.  Some fresh castings were seen close to the stone.
Nevertheless, on digging a large hole to a depth of 18 inches where the
stone had lain, only two worms and a few burrows were seen, although the
soil was damp and seemed favourable for worms.  There were some large
colonies of ants beneath the stone, and possibly since their
establishment the worms had decreased in number.

The third stone was only about half as large as the others; and two
strong boys could together have rolled it over.  I have no doubt that it
had been rolled over at a moderately recent time, for it now lay at some
distance from the two other stones at the bottom of a little adjoining
slope.  It rested also on fine earth, instead of partly on brick-rubbish.
In agreement with this conclusion, the raised surrounding border of turf
was only 1 inch high in some parts, and 2 inches in other parts.  There
were no colonies of ants beneath this stone, and on digging a hole where
it had lain, several burrows and worms were found.

At Stonehenge, some of the outer Druidical stones are now prostrate,
having fallen at a remote but unknown period; and these have become
buried to a moderate depth in the ground.  They are surrounded by sloping
borders of turf, on which recent castings were seen.  Close to one of
these fallen stones, which was 17 ft long, 6 ft. broad, and 28½ inches
thick, a hole was dug; and here the vegetable mould was at least 9½
inches in thickness.  At this depth a flint was found, and a little
higher up on one side of the hole a fragment of glass.  The base of the
stone lay about 9½ inches beneath the level of the surrounding ground,
and its upper surface 19 inches above the ground.

A hole was also dug close to a second huge stone, which in falling had
broken into two pieces; and this must have happened long ago, judging
from the weathered aspect of the fractured ends.  The base was buried to
a depth of 10 inches, as was ascertained by driving an iron skewer
horizontally into the ground beneath it.  The vegetable mould forming the
turf-covered sloping border round the stone, on which many castings had
recently been ejected, was 10 inches in thickness; and most of this mould
must have been brought up by worms from beneath its base.  At a distance
of 8 yards from the stone, the mould was only 5½ inches in thickness
(with a piece of tobacco pipe at a depth of 4 inches), and this rested on
broken flint and chalk which could not have easily yielded to the
pressure or weight of the stone.

A straight rod was fixed horizontally (by the aid of a spirit-level)
across a third fallen stone, which was 7 feet 9 inches long; and the
contour of the projecting parts and of the adjoining ground, which was
not quite level, was thus ascertained, as shown in the accompanying
diagram (Fig. 7) on a scale of ½ inch to a foot.  The turf-covered border
sloped up to the stone on one side to a height of 4 inches, and on the
opposite side to only 2½ inches above the general level.  A hole was dug
on the eastern side, and the base of the stone was here found to lie at a
depth of 4 inches beneath the general level of the ground, and of 8
inches beneath the top of the sloping turf-covered border.

                                * * * * *

Sufficient evidence has now been given showing that small objects left on
the surface of the land where worms abound soon get buried, and that
large stones sink slowly downwards through the same means.  Every step of
the process could be followed, from the accidental deposition of a single
casting on a small object lying loose on the surface, to its being
entangled amidst the matted roots of the turf, and lastly to its being
embedded in the mould at various depths beneath the surface.  When the
same field was re-examined after the interval of a few years, such
objects were found at a greater depth than before.  The straightness and
regularity of the lines formed by the imbedded objects, and their
parallelism with the surface of the land, are the most striking features
of the case; for this parallelism shows how equably the worms must have
worked; the result being, however, partly the effect of the washing down
of the fresh castings by rain.  The specific gravity of the objects does
not affect their rate of sinking, as could be seen by porous cinders,
burnt marl, chalk and quartz pebbles, having all sunk to the same depth
within the same time.  Considering the nature of the substratum, which at
Leith Hill Place was sandy soil including many bits of rock, and at
Stonehenge, chalk-rubble with broken flints; considering, also, the
presence of the turf-covered sloping border of mould round the great
fragments of stone at both these places, their sinking does not appear to
have been sensibly aided by their weight, though this was considerable.
{147}

_On the number of worms which live within a given space_.—We will now
show, firstly, what a vast number of worms live unseen by us beneath our
feet, and, secondly, the actual weight of the earth which they bring up
to the surface within a given space and within a given time.  Hensen, who
has published so full and interesting an account of the habits of worms,
{148} calculates, from the number which he found in a measured space,
that there must exist 133,000 living worms in a hectare of land, or
53,767 in an acre.  This latter number of worms would weigh 356 pounds,
taking Hensen’s standard of the weight of a single worm, namely, three
grams.  It should, however, be noted that this calculation is founded on
the numbers found in a garden, and Hensen believes that worms are here
twice as numerous as in corn-fields.  The above result, astonishing
though it be, seems to me credible, judging from the number of worms
which I have sometimes seen, and from the number daily destroyed by birds
without the species being exterminated.  Some barrels of bad ale were
left on Mr. Miller’s land, {149} in the hope of making vinegar, but the
vinegar proved bad, and the barrels were upset.  It should be premised
that acetic acid is so deadly a poison to worms that Perrier found that a
glass rod dipped into this acid and then into a considerable body of
water in which worms were immersed, invariably killed them quickly.  On
the morning after the barrels had been upset, “the heaps of worms which
lay dead on the ground were so amazing, that if Mr. Miller had not seen
them, he could not have thought it possible for such numbers to have
existed in the space.”  As further evidence of the large number of worms
which live in the ground, Hensen states that he found in a garden
sixty-four open burrows in a space of 14½ square feet, that is, nine in 2
square feet.  But the burrows are sometimes much more numerous, for when
digging in a grass-field near Maer Hall, I found a cake of dry earth, as
large as my two open hands, which was penetrated by seven burrows, as
large as goose-quills.

_Weight of the earth ejected from a single burrow_, _and from all the
burrows within a given space_.—With respect to the weight of the earth
daily ejected by worms, Hensen found that it amounted, in the case of
some worms which he kept in confinement, and which he appears to have fed
with leaves, to only 0.5 gram, or less than 8 grains per diem.  But a
very much larger amount must be ejected by worms in their natural state,
at the periods when they consume earth as food instead of leaves, and
when they are making deep burrows.  This is rendered almost certain by
the following weights of the castings thrown up at the mouths of single
burrows; the whole of which appeared to have been ejected within no long
time, as was certainly the case in several instances.  The castings were
dried (excepting in one specified instance) by exposure during many days
to the sun or before a hot fire.

 WEIGHT OF THE CASTINGS ACCUMULATED AT THE MOUTH OF A SINGLE BURROW.
(1.)  Down, Kent (sub-soil red clay, full of flints,              3.98
over-lying the chalk).  The largest casting which I could
find on the flanks of a steep valley, the sub-soil being
here shallow.  In this one case, the casting was not well
dried
(2.)  Down.—Largest casting which I could find (consisting        3.87
chiefly of calcareous matter), on extremely poor pasture
land at the bottom of the valley mentioned under (1.)
(3.)  Down.—A large casting, but not of unusual size, from        1.22
a nearly level field, poor pasture, laid down in a grass
about 35 years before
(4.)  Down.  Average weight of 11 not large castings               0.7
ejected on a sloping surface on my lawn, after they had
suffered some loss of weight from being exposed during a
considerable length of time to rain
(5.)  Near Nice in France.—Average weight of 12 castings of       1.37
ordinary dimensions, collected by Dr. King on land which
had not been mown for a long time and where worms abounded,
viz., a lawn protected by shrubberies near the sea; soil
sandy and calcareous; these castings had been exposed for
some time to rain, before being collected, and must have
lost some weight by disintegration, but they still retained
their form
(6.)  The heaviest of the above twelve castings                   1.76
(7.)   Lower Bengal.—Average weight of 22 castings,               1.24
collected by Mr. J. Scott, and stated by him to have been
thrown up in the course of one or two nights
(8.)  The heaviest of the above 22 castings                       2.09
(9.)  Nilgiri Mountains, S. India; average weight of the 5        3.15
largest castings collected by Dr. King.  They had been
exposed to the rain of the last monsoon, and must have lost
some weight
(10.)  The heaviest of the above 5 castings                       4.34

In this table we see that castings which had been ejected at the mouth of
the same burrow, and which in most cases appeared fresh and always
retained their vermiform configuration, generally exceeded an ounce in
weight after being dried, and sometimes nearly equalled a quarter of a
pound.  On the Nilgiri mountains one casting even exceeded this latter
weight.  The largest castings in England were found on extremely poor
pasture-land; and these, as far as I have seen, are generally larger than
those on land producing a rich vegetation.  It would appear that worms
have to swallow a greater amount of earth on poor than on rich land, in
order to obtain sufficient nutriment.

With respect to the tower-like castings near Nice (Nos. 5 and 6 in the
above table), Dr. King often found five or six of them on a square foot
of surface; and these, judging from their average weight, would have
weighed together 7½ ounces; so that the weight of those on a square yard
would have been 4 lb. 3½ oz.  Dr. King collected, near the close of the
year 1872, all the castings which still retained their vermiform shape,
whether broken down or not, from a square foot, in a place abounding with
worms, on the summit of a bank, where no castings could have rolled down
from above.  These castings must have been ejected, as he judged from
their appearance in reference to the rainy and dry periods near Nice,
within the previous five or six months; they weighed 9½ oz., or 5 lb. 5½
oz. per square yard.  After an interval of four months, Dr. King
collected all the castings subsequently ejected on the same square foot
of surface, and they weighed 2½ oz., or 1 lb. 6½ oz. per square yard.
Therefore within about ten months, or we will say for safety’s sake
within a year, 12 oz. of castings were thrown up on this one square foot,
or 6.75 pounds on the square yard; and this would give 14.58 tons per
acre.

In a field at the bottom of a valley in the chalk (see No. 2 in the
foregoing table), a square yard was measured at a spot where very large
castings abounded; they appeared, however, almost equally numerous in a
few other places.  These castings, which retained perfectly their
vermiform shape, were collected; and they weighed when partially dried, 1
lb. 13½ oz.  This field had been rolled with a heavy agricultural roller
fifty-two days before, and this would certainly have flattened every
single casting on the land.  The weather had been very dry for two or
three weeks before the day of collection, so that not one casting
appeared fresh or had been recently ejected.  We may therefore assume
that those which were weighed had been ejected within, we will say, forty
days from the time when the field was rolled,—that is, twelve days short
of the whole intervening period.  I had examined the same part of the
field shortly before it was rolled, and it then abounded with fresh
castings.  Worms do not work in dry weather during the summer, or in
winter during severe frosts.  If we assume that they work for only half
the year—though this is too low an estimate—then the worms in this field
would eject during the year, 8.387 pounds per square yard; or 18.12 tons
per acre, assuming the whole surface to be equally productive in
castings.

In the foregoing cases some of the necessary data had to be estimated,
but in the two following cases the results are much more trustworthy.  A
lady, on whose accuracy I can implicitly rely, offered to collect during
a year all the castings thrown up on two separate square yards, near
Leith Hill Place, in Surrey.  The amount collected was, however, somewhat
less than that originally ejected by the worms; for, as I have repeatedly
observed, a good deal of the finest earth is washed away, whenever
castings are thrown up during or shortly before heavy rain.  Small
portions also adhered to the surrounding blades of grass, and it required
too much time to detach every one of them.

On sandy soil, as in the present instance, castings are liable to crumble
after dry weather, and particles were thus often lost.  The lady also
occasionally left home for a week or two, and at such times the castings
must have suffered still greater loss from exposure to the weather.
These losses were, however, compensated to some extent by the collections
having been made on one of the squares for four days, and on the other
square for two days more than the year.

A space was selected (October 9th, 1870) for one of the squares on a
broad, grass-covered terrace, which had been mowed and swept during many
years.  It faced the south, but was shaded during part of the day by
trees.  It had been formed at least a century ago by a great accumulation
of small and large fragments of sandstone, together with some sandy
earth, rammed down level.  It is probable that it was at first protected
by being covered with turf.  This terrace, judging from the number of
castings on it, was rather unfavourable for the existence of worms, in
comparison with the neighbouring fields and an upper terrace.  It was
indeed surprising that as many worms could live here as were seen; for on
digging a hole in this terrace, the black vegetable mould together with
the turf was only four inches in thickness, beneath which lay the level
surface of light-coloured sandy soil, with many fragments of sandstone.
Before any castings were collected all the previously existing ones were
carefully removed.  The last day’s collection was on October 14th, 1871.
The castings were then well dried before a fire; and they weighed exactly
3½ lbs.  This would give for an acre of similar land 7.56 tons of dry
earth annually ejected by worms.

The second square was marked on unenclosed common land, at a height of
about 700 ft. above the sea, at some little distance from Leith Hill
Tower.  The surface was clothed with short, fine turf, and had never been
disturbed by the hand of man.  The spot selected appeared neither
particularly favourable nor the reverse for worms; but I have often
noticed that castings are especially abundant on common land, and this
may, perhaps, be attributed to the poorness of the soil.  The vegetable
mould was here between three and four inches in thickness.  As this spot
was at some distance from the house where the lady lived, the castings
were not collected at such short intervals of time as those on the
terrace; consequently the loss of fine earth during rainy weather must
have been greater in this than in the last case.  The castings moreover
were more sandy, and in collecting them during dry weather they sometimes
crumbled into dust, and much was thus lost.  Therefore it is certain that
the worms brought up to the surface considerably more earth than that
which was collected.  The last collection was made on October 27th, 1871;
i.e., 367 days after the square had been marked out and the surface
cleared of all pre-existing castings.  The collected castings, after
being well dried, weighed 7.453 pounds; and this would give, for an acre
of the same kind of land, 16.1 tons of annually ejected dry earth.

                 SUMMARY OF THE FOUR FOREGOING CASES.
(1.)  Castings ejected near Nice within about a year, collected by Dr.
King on a square foot of surface, calculated to yield per acre 14.58
tons.
(2.)  Castings ejected during about 40 days on a square yard, in a
field of poor pasture at the bottom of a large valley in the Chalk,
calculated to yield annually per acre 18.12 tons.
(3.)  Castings collected from a square yard on an old terrace at Leith
Hill Place, during 369 days, calculated to yield annually per acre
7.56 tons.
(4.)  Castings collected from a square yard on Leith Hill Common
during 367 days, calculated to yield annually per acre 16.1 tons.

_The thickness of the layer of mould_, _which castings ejected during a
year would form if uniformly spread out_.—As we know, from the two last
cases in the above summary, the weight of the dried castings ejected by
worms during a year on a square yard of surface, I wished to learn how
thick a layer of ordinary mould this amount would form if spread
uniformly over a square yard.  The dry castings were therefore broken
into small particles, and whilst being placed in a measure were well
shaken and pressed down.  Those collected on the Terrace amounted to
124.77 cubic inches; and this amount, if spread out over a square yard,
would make a layer 0.9627 inch in thickness.  Those collected on the
Common amounted to 197.56 cubic inches, and would make a similar layer
0.1524 inch in thickness.

These thicknesses must, however, be corrected, for the triturated
castings, after being well shaken down and pressed, did not make nearly
so compact a mass as vegetable mould, though each separate particle was
very compact.  Yet mould is far from being compact, as is shown by the
number of air-bubbles which rise up when the surface is flooded with
water.  It is moreover penetrated by many fine roots.  To ascertain
approximately by how much ordinary vegetable mould would be increased in
bulk by being broken up into small particles and then dried, a thin
oblong block of somewhat argillaceous mould (with the turf pared off) was
measured before being broken up, was well dried and again measured.  The
drying caused it to shrink by 1/7 of its original bulk, judging from
exterior measurements alone.  It was then triturated and partly reduced
to powder, in the same manner as the castings had been treated, and its
bulk now exceeded (notwithstanding shrinkage from drying) by 1/16 that of
the original block of damp mould.  Therefore the above calculated
thickness of the layer, formed by the castings from the Terrace, after
being damped and spread over a square yard, would have to be reduced by
1/16; and this will reduce the layer to 0.09 of an inch, so that a layer
0.9 inch in thickness would be formed in the course of ten years.  On the
same principle the castings from the Common would make in the course of a
single year a layer 0.1429 inch, or in the course of 10 years 1.429 inch,
in thickness.  We may say in round numbers that the thickness in the
former case would amount to nearly 1 inch, and in the second case to
nearly 1½ inch in 10 years.

In order to compare these results with those deduced from the rates at
which small objects left on the surfaces of grass-fields become buried
(as described in the early part of this chapter), we will give the
following summary:—

  SUMMARY OF THE THICKNESS OF THE MOULD ACCUMULATED OVER OBJECTS LEFT
          STREWED ON THE SURFACE, IN THE COURSE OF TEN YEARS.
The accumulation of mould during 14¾ years on the surface of a dry,
sandy, grass-field near Maer Hall, amounted to 2.2 inches in 10 years.
The accumulation during 21½ years on a swampy field near Maer Hall,
amounted to nearly 1.9 inch in 10 years.
The accumulation during 7 years on a very swampy field near Maer Hall
amounted to 2.1 inches in 10 years.
The accumulation during 29 years, on good, argillaceous pasture-land
over the Chalk at Down, amounted to 2.2 inches in 10 years.
The accumulation during 30 years on the side of a valley over the
Chalk at Down, the soil being argillaceous, very poor, and only just
converted into pasture (so that it was for some years unfavourable for
worms), amounted to 0.83 inch in 10 years.

In these cases (excepting the last) it may be seen that the amount of
earth brought to the surface during 10 years is somewhat greater than
that calculated from the castings which were actually weighed.  This
excess may be partly accounted for by the loss which the weighed castings
had previously undergone through being washed by rain, by the adhesion of
particles to the blades of the surrounding grass, and by their crumbling
when dry.  Nor must we overlook other agencies which in all ordinary
cases add to the amount of mould, and which would not be included in the
castings that were collected, namely, the fine earth brought up to the
surface by burrowing larvæ and insects, especially by ants.  The earth
brought up by moles generally has a somewhat different appearance from
vegetable mould; but after a time would not be distinguishable from it.
In dry countries, moreover, the wind plays an important part in carrying
dust from one place to another, and even in England it must add to the
mould on fields near great roads.  But in our country these latter
several agencies appear to be of quite subordinate importance in
comparison with the action of worms.

We have no means of judging how great a weight of earth a single
full-sized worm ejects during a year.  Hensen estimates that 53,767 worms
exist in an acre of land; but this is founded on the number found in
gardens, and he believes that only about half as many live in
corn-fields.  How many live in old pasture land is unknown; but if we
assume that half the above number, or 26,886 worms live on such land,
then taking from the previous summary 15 tons as the weight of the
castings annually thrown up on an acre of land, each worm must annually
eject 20 ounces.  A full-sized casting at the mouth of a single burrow
often exceeds, as we have seen, an ounce in weight; and it is probable
that worms eject more than 20 full-sized castings during a year.  If they
eject annually more than 20 ounces, we may infer that the worms which
live in an acre of pasture land must be less than 26,886 in number.

Worms live chiefly in the superficial mould, which is usually from 4 or 5
to 10 and even 12 inches in thickness; and it is this mould which passes
over and over again through their bodies and is brought to the surface.
But worms occasionally burrow into the subsoil to a much greater depth,
and on such occasions they bring up earth from this greater depth; and
this process has gone on for countless ages.  Therefore the superficial
layer of mould would ultimately attain, though at a slower and slower
rate, a thickness equal to the depth to which worms ever burrow, were
there not other opposing agencies at work which carry away to a lower
level some of the finest earth which is continually being brought to the
surface by worms.  How great a thickness vegetable mould ever attains, I
have not had good opportunities for observing; but in the next chapter,
when we consider the burial of ancient buildings, some facts will be
given on this head.  In the two last chapters we shall see that the soil
is actually increased, though only to a small degree, through the agency
of worms; but their chief work is to sift the finer from the coarser
particles, to mingle the whole with vegetable débris, and to saturate it
with their intestinal secretions.

Finally, no one who considers the facts given in this chapter—on the
burying of small objects and on the sinking of great stones left on the
surface—on the vast number of worms which live within a moderate extent
of ground on the weight of the castings ejected from the mouth of the
same burrow—on the weight of all the castings ejected within a known time
on a measured space—will hereafter, as I believe, doubt that worms play
an important part in nature.




CHAPTER IV.
THE PART WHICH WORMS HAVE PLAYED IN THE BURIAL OF ANCIENT BUILDINGS.


The accumulation of rubbish on the sites of great cities independent of
the action of worms—The burial of a Roman villa at Abinger—The floors and
walls penetrated by worms—Subsidence of a modern pavement—The buried
pavement at Beaulieu Abbey—Roman villas at Chedworth and Brading—The
remains of the Roman town at Silchester—The nature of the débris by which
the remains are covered—The penetration of the tesselated floors and
walls by worms—Subsidence of the floors—Thickness of the mould—The old
Roman city of Wroxeter—Thickness of the mould—Depth of the foundations of
some of the Buildings—Conclusion.

ARCHÆOLOGISTS are probably not aware how much they owe to worms for the
preservation of many ancient objects.  Coins, gold ornaments, stone
implements, &c., if dropped on the surface of the ground, will infallibly
be buried by the castings of worms in a few years, and will thus be
safely preserved, until the land at some future time is turned up.  For
instance, many years ago a grass-field was ploughed on the northern side
of the Severn, not far from Shrewsbury; and a surprising number of iron
arrow-heads were found at the bottom of the furrows, which, as Mr.
Blakeway, a local antiquary, believed, were relics of the battle of
Shrewsbury in the year 1403, and no doubt had been originally left
strewed on the battle-field.  In the present chapter I shall show that
not only implements, &c., are thus preserved, but that the floors and the
remains of many ancient buildings in England have been buried so
effectually, in large part through the action of worms, that they have
been discovered in recent times solely through various accidents.  The
enormous beds of rubbish, several yards in thickness, which underlie many
cities, such as Rome, Paris, and London, the lower ones being of great
antiquity, are not here referred to, as they have not been in any way
acted on by worms.  When we consider how much matter is daily brought
into a great city for building, fuel, clothing and food, and that in old
times when the roads were bad and the work of the scavenger was
neglected, a comparatively small amount was carried away, we may agree
with Élie de Beaumont, who, in discussing this subject, says, “pour une
voiture de matériaux qui en sort, on y en fait entrer cent.” {166a}  Nor
should we overlook the effects of fires, the demolition of old buildings,
and the removal of rubbish to the nearest vacant space.

_Abinger_, _Surrey_.—Late in the autumn of 1876, the ground in an old
farm-yard at this place was dug to a depth of 2 to 2½ feet, and the
workmen found various ancient remains.  This led Mr. T. H. Farrer of
Abinger Hall to have an adjoining ploughed field searched.  On a trench
being dug, a layer of concrete, still partly covered with tesseræ (small
red tiles), and surrounded on two sides by broken-down walls, was soon
discovered.  It is believed, {166b} that this room formed part of the
atrium or reception-room of a Roman villa.  The walls of two or three
other small rooms were afterwards discovered.  Many fragments of pottery,
other objects, and coins of several Roman emperors, dating from 133 to
361, and perhaps to 375 A.D., were likewise found.  Also a half-penny of
George I., 1715.  The presence of this latter coin seems an anomaly; but
no doubt it was dropped on the ground during the last century, and since
then there has been ample time for its burial under a considerable depth
of the castings of worms.  From the different dates of the Roman coins we
may infer that the building was long inhabited.  It was probably ruined
and deserted 1400 or 1500 years ago.

I was present during the commencement of the excavations (August 20,
1877) and Mr. Farrer had two deep trenches dug at opposite ends of the
atrium, so that I might examine the nature of the soil near the remains.
The field sloped from east to west at an angle of about 7°; and one of
the two trenches, shown in the accompanying section (Fig. 8) was at the
upper or eastern end.  The diagram is on a scale of 1/20 of an inch to an
inch; but the trench, which was between 4 and 5 feet broad, and in parts
above 5 feet deep, has necessarily been reduced out of all proportion.
The fine mould over the floor of the atrium varied in thickness from 11
to 16 inches; and on the side of the trench in the section was a little
over 13 inches.  After the mould had been removed, the floor appeared as
a whole moderately level; but it sloped in parts at an angle of 1°, and
in one place near the outside at as much as 8° 30'.  The wall surrounding
the pavement was built of rough stones, and was 23 inches in thickness
where the trench was dug.  Its broken summit was here 13 inches, but in
another part 15 inches, beneath the surface of the field, being covered
by this thickness of mould.  In one spot, however, it rose to within 6
inches of the surface.  On two sides of the room, where the junction of
the concrete floor with the bounding walls could be carefully examined,
there was no crack or separation.  This trench afterwards proved to have
been dug within an adjoining room (11 ft. by 11 ft. 6 in. in size), the
existence of which was not even suspected whilst I was present.

   [Picture: Fig. 8: Section through the foundations of a buried Roman
                                  villa]

On the side of the trench farthest from the buried wall (W), the mould
varied from 9 to 14 inches in thickness; it rested on a mass (B) 23
inches thick of blackish earth, including many large stones.  Beneath
this was a thin bed of very black mould (C), then a layer of earth full
of fragments of mortar (D), and then another thin bed (about 3 inches
thick) (E) of very black mould, which rested on the undisturbed subsoil
(F) of firm, yellowish, argillaceous sand.  The 23-inch bed (B) was
probably made ground, as this would have brought up the floor of the room
to a level with that of the atrium.  The two thin beds of black mould at
the bottom of the trench evidently marked two former land-surfaces.
Outside the walls of the northern room, many bones, ashes, oyster-shells,
broken pottery and an entire pot were subsequently found at a depth of 16
inches beneath the surface.

The second trench was dug on the western or lower side of the villa: the
mould was here only 6½ inches in thickness, and it rested on a mass of
fine earth full of stones, broken tiles and fragments of mortar, 34
inches in thickness, beneath which was the undisturbed sand.  Most of
this earth had probably been washed down from the upper part of the
field, and the fragments of stones, tiles, &c., must have come from the
immediately adjoining ruins.

It appears at first sight a surprising fact that this field of light
sandy soil should have been cultivated and ploughed during many years,
and that not a vestige of these buildings should have been discovered.
No one even suspected that the remains of a Roman villa lay hidden close
beneath the surface.  But the fact is less surprising when it is known
that the field, as the bailiff believed, had never been ploughed to a
greater depth than 4 inches.  It is certain that when the land was first
ploughed, the pavement and the surrounding broken walls must have been
covered by at least 4 inches of soil, for otherwise the rotten concrete
floor would have been scored by the ploughshare, the tesseræ torn up, and
the tops of the old walls knocked down.

When the concrete and tesseræ were first cleared over a space of 14 by 9
ft., the floor which was coated with trodden-down earth exhibited no
signs of having been penetrated by worms; and although the overlying fine
mould closely resembled that which in many places has certainly been
accumulated by worms, yet it seemed hardly possible that this mould could
have been brought up by worms from beneath the apparently sound floor.
It seemed also extremely improbable that the thick walls, surrounding the
room and still united to the concrete, had been undermined by worms, and
had thus been caused to sink, being afterwards covered up by their
castings.  I therefore at first concluded that all the fine mould above
the ruins had been washed down from the upper parts of the field; but we
shall soon see that this conclusion was certainly erroneous, though much
fine earth is known to be washed down from the upper part of the field in
its present ploughed state during heavy rains.

Although the concrete floor did not at first appear to have been anywhere
penetrated by worms, yet by the next morning little cakes of the
trodden-down earth had been lifted up by worms over the mouths of seven
burrows, which passed through the softer parts of the naked concrete, or
between the interstices of the tesseræ.  On the third morning twenty-five
burrows were counted; and by suddenly lifting up the little cakes of
earth, four worms were seen in the act of quickly retreating.  Two
castings were thrown up during the third night on the floor, and these
were of large size.  The season was not favourable for the full activity
of worms, and the weather had lately been hot and dry, so that most of
the worms now lived at a considerable depth.  In digging the two trenches
many open burrows and some worms were encountered at between 30 and 40
inches beneath the surface; but at a greater depth they became rare.  One
worm, however, was cut through at 48½, and another at 51½ inches beneath
the surface.  A fresh humus-lined burrow was also met with at a depth of
57 and another at 65½ inches.  At greater depths than this, neither
burrows nor worms were seen.

As I wished to learn how many worms lived beneath the floor of the
atrium—a space of about 14 by 9 feet—Mr. Farrer was so kind as to make
observations for me, during the next seven weeks, by which time the worms
in the surrounding country were in full activity, and were working near
the surface.  It is very improbable that worms should have migrated from
the adjoining field into the small space of the atrium, after the
superficial mould in which they prefer to live, had been removed.  We may
therefore conclude that the burrows and the castings which were seen here
during the ensuing seven weeks were the work of the former inhabitants of
the space.  I will now give a few extracts from Mr. Farrer’s notes.

Aug. 26th, 1877; that is, five days after the floor had been cleared.  On
the previous night there had been some heavy rain, which washed the
surface clean, and now the mouths of forty burrows were counted.  Parts
of the concrete were seen to be solid, and had never been penetrated by
worms, and here the rain-water lodged.

Sept. 5th.—Tracks of worms, made during the previous night, could be seen
on the surface of the floor, and five or six vermiform castings had been
thrown up.  These were defaced.

Sept. 12th.—During the last six days, the worms have not been active,
though many castings have been ejected in the neighbouring fields; but on
this day the earth was a little raised over the mouths of the burrows, or
castings were ejected, at ten fresh points.  These were defaced.  It
should be understood that when a fresh burrow is spoken of, this
generally means only that an old burrow has been re-opened.  Mr. Farrer
was repeatedly struck with the pertinacity with which the worms re-opened
their old burrows, even when no earth was ejected from them.  I have
often observed the same fact, and generally the mouths of the burrows are
protected by an accumulation of pebbles, sticks or leaves.  Mr. Farrer
likewise observed that the worms living beneath the floor of the atrium
often collected coarse grains of sand, and such little stones as they
could find, round the mouths of their burrows.

Sept. 13th; soft wet weather.  The mouths of the burrows were re-opened,
or castings were ejected, at 31 points; these were all defaced.

Sept. 14th; 34 fresh holes or castings; all defaced.

Sept. 15th; 44 fresh holes, only 5 castings; all defaced.

Sept. 18th; 43 fresh holes, 8 castings; all defaced.

The number of castings on the surrounding fields was now very large.

Sept. 19th; 40 holes, 8 castings; all defaced.

Sept. 22nd; 43 holes, only a few fresh castings; all defaced.

Sept. 23rd; 44 holes, 8 castings.

Sept. 25th; 50 holes, no record of the number of castings.

Oct. 13th;  61 holes, no record of the number of castings.

After an interval of three years, Mr. Farrer, at my request, again looked
at the concrete floor, and found the worms still at work.

Knowing what great muscular power worms possess, and seeing how soft the
concrete was in many parts, I was not surprised at its having been
penetrated by their burrows; but it is a more surprising fact that the
mortar between the rough stones of the thick walls, surrounding the
rooms, was found by Mr. Farrer to have been penetrated by worms.  On
August 26th, that is, five days after the ruins had been exposed, he
observed four open burrows on the broken summit of the eastern wall (W in
Fig. 8); and, on September 15th, other burrows similarly situated were
seen.  It should also be noted that in the perpendicular side of the
trench (which was much deeper than is represented in Fig. 8) three recent
burrows were seen, which ran obliquely far down beneath the base of the
old wall.

We thus see that many worms lived beneath the floor and the walls of the
atrium at the time when the excavations were made; and that they
afterwards almost daily brought up earth to the surface from a
considerable depth.  There is not the slightest reason to doubt that
worms have acted in this manner ever since the period when the concrete
was sufficiently decayed to allow them to penetrate it; and even before
that period they would have lived beneath the floor, as soon as it became
pervious to rain, so that the soil beneath was kept damp.  The floor and
the walls must therefore have been continually undermined; and fine earth
must have been heaped on them during many centuries, perhaps for a
thousand years.  If the burrows beneath the floor and walls, which it is
probable were formerly as numerous as they now are, had not collapsed in
the course of time in the manner formerly explained, the underlying earth
would have been riddled with passages like a sponge; and as this was not
the case, we may feel sure that they have collapsed.  The inevitable
result of such collapsing during successive centuries, will have been the
slow subsidence of the floor and of the walls, and their burial beneath
the accumulated worm-castings.  The subsidence of a floor, whilst it
still remains nearly horizontal, may at first appear improbable; but the
case presents no more real difficulty than that of loose objects strewed
on the surface of a field, which, as we have seen, become buried several
inches beneath the surface in the course of a few years, though still
forming a horizontal layer parallel to the surface.  The burial of the
paved and level path on my lawn, which took place under my own
observation, is an analogous case.  Even those parts of the concrete
floor which the worms could not penetrate would almost certainly have
been undermined, and would have sunk, like the great stones at Leith Hill
Place and Stonehenge, for the soil would have been damp beneath them.
But the rate of sinking of the different parts would not have been quite
equal, and the floor was not quite level.  The foundations of the
boundary walls lie, as shown in the section, at a very small depth
beneath the surface; they would therefore have tended to subside at
nearly the same rate as the floor.  But this would not have occurred if
the foundations had been deep, as in the case of some other Roman ruins
presently to be described.

Finally, we may infer that a large part of the fine vegetable mould,
which covered the floor and the broken-down walls of this villa, in some
places to a thickness of 16 inches, was brought up from below by worms.
From facts hereafter to be given there can be no doubt that some of the
finest earth thus brought up will have been washed down the sloping
surface of the field during every heavy shower of rain.  If this had not
occurred a greater amount of mould would have accumulated over the ruins
than that now present.  But beside the castings of worms and some earth
brought up by insects, and some accumulation of dust, much fine earth
will have been washed over the ruins from the upper parts of the field,
since it has been under cultivation; and from over the ruins to the lower
parts of the slope; the present thickness of the mould being the
resultant of these several agencies.

                                * * * * *

I may here append a modern instance of the sinking of a pavement,
communicated to me in 1871 by Mr. Ramsay, Director of the Geological
Survey of England.  A passage without a roof, 7 feet in length by 3 feet
2 inches in width, led from his house into the garden, and was paved with
slabs of Portland stone.  Several of these slabs were 16 inches square,
others larger, and some a little smaller.  This pavement had subsided
about 3 inches along the middle of the passage, and two inches on each
side, as could be seen by the lines of cement by which the slabs had been
originally joined to the walls.  The pavement had thus become slightly
concave along the middle; but there was no subsidence at the end close to
the house.  Mr. Ramsay could not account for this sinking, until he
observed that castings of black mould were frequently ejected along the
lines of junction between the slabs; and these castings were regularly
swept away.  The several lines of junction, including those with the
lateral walls, were altogether 39 feet 2 inches in length.  The pavement
did not present the appearance of ever having been renewed, and the house
was believed to have been built about eighty-seven years ago.
Considering all these circumstances, Mr. Ramsay does not doubt that the
earth brought up by the worms since the pavement was first laid down, or
rather since the decay of the mortar allowed the worms to burrow through
it, and therefore within a much shorter time than the eighty-seven years,
has sufficed to cause the sinking of the pavement to the above amount,
except close to the house, where the ground beneath would have been kept
nearly dry.

Beaulieu Abbey, Hampshire.—This abbey was destroyed by Henry VIII., and
there now remains only a portion of the southern aisle-wall.  It is
believed that the king had most of the stones carried away for building a
castle; and it is certain that they have been removed.  The positions of
the nave and transepts were ascertained not long ago by the foundations
having been found; and the place is now marked by stones let into the
ground.  Where the abbey formerly stood, there now extends a smooth
grass-covered surface, which resembles in all respects the rest of the
field.  The guardian, a very old man, said the surface had never been
levelled in his time.  In the year 1853, the Duke of Buccleuch had three
holes dug in the turf within a few yards of one another, at the western
end of the nave; and the old tesselated pavement of the abbey was thus
discovered.  These holes were afterwards surrounded by brickwork, and
protected by trap-doors, so that the pavement might be readily inspected
and preserved.  When my son William examined the place on January 5,
1872, he found that the pavement in the three holes lay at depths of 6¾,
10 and 11½ inches beneath the surrounding turf-covered surface.  The old
guardian asserted that he was often forced to remove worm-castings from
the pavement; and that he had done so about six months before.  My son
collected all from one of the holes, the area of which was 5.32 square
feet, and they weighed 7.97 ounces.  Assuming that this amount had
accumulated in six months, the accumulation during a year on a square
yard would be 1.68 pounds, which, though a large amount, is very small
compared with what, as we have seen, is often ejected on fields and
commons.  When I visited the abbey on June 22, 1877, the old man said
that he had cleared out the holes about a month before, but a good many
castings had since been ejected.  I suspect that he imagined that he
swept the pavements oftener than he really did, for the conditions were
in several respects very unfavourable for the accumulation of even a
moderate amount of castings.  The tiles are rather large, viz., about 5½
inches square, and the mortar between them was in most places sound, so
that the worms were able to bring up earth from below only at certain
points.  The tiles rested on a bed of concrete, and the castings in
consequence consisted in large part (viz., in the proportion of 19 to 33)
of particles of mortar, grains of sand, little fragments of rock, bricks
or tile; and such substances could hardly be agreeable, and certainly not
nutritious, to worms.

My son dug holes in several places within the former walls of the abbey,
at a distance of several yards from the above described bricked squares.
He did not find any tiles, though these are known to occur in some other
parts, but he came in one spot to concrete on which tiles had once
rested.  The fine mould beneath the turf on the sides of the several
holes, varied in thickness from only 2 to 2¾ inches, and this rested on a
layer from 8¾ to above 11 inches in thickness, consisting of fragments of
mortar and stone-rubbish with the interstices compactly filled up with
black mould.  In the surrounding field, at a distance of 20 yards from
the abbey, the fine vegetable mould was 11 inches thick.

We may conclude from these facts that when the abbey was destroyed and
the stones removed, a layer of rubbish was left over the whole surface,
and that as soon as the worms were able to penetrate the decayed concrete
and the joints between the tiles, they slowly filled up the interstices
in the overlying rubbish with their castings, which were afterwards
accumulated to a thickness of nearly three inches over the whole surface.
If we add to this latter amount the mould between the fragments of
stones, some five or six inches of mould must have been brought up from
beneath the concrete or tiles.  The concrete or tiles will consequently
have subsided to nearly this amount.  The bases of the columns of the
aisles are now buried beneath mould and turf.  It is not probable that
they can have been undermined by worms, for their foundations would no
doubt have been laid at a considerable depth.  If they have not subsided,
the stones of which the columns were constructed must have been removed
from beneath the former level of the floor.

_Chedworth_, _Gloucestershire_.—The remains of a large Roman villa were
discovered here in 1866, on ground which had been covered with wood from
time immemorial.  No suspicion seems ever to have been entertained that
ancient buildings lay buried here, until a gamekeeper, in digging for
rabbits, encountered some remains. {183}  But subsequently the tops of
some stone walls were detected in parts of the wood, projecting a little
above the surface of the ground.  Most of the coins found here belonged
to Constans (who died 350 A.D.) and the Constantine family.  My sons
Francis and Horace visited the place in November 1877, for the sake of
ascertaining what part worms may have played in the burial of these
extensive remains.  But the circumstances were not favourable for this
object, as the ruins are surrounded on three sides by rather steep banks,
down which earth is washed during rainy weather.  Moreover most of the
old rooms have been covered with roofs, for the protection of the elegant
tesselated pavements.

A few facts may, however, be given on the thickness of the soil over
these ruins.  Close outside the northern rooms there is a broken wall,
the summit of which was covered by 5 inches of black mould; and in a hole
dug on the outer side of this wall, where the ground had never before
been disturbed, black mould, full of stones, 26 inches in thickness, was
found, resting on the undisturbed sub-soil of yellow clay.  At a depth of
22 inches from the surface a pig’s jaw and a fragment of a tile were
found.  When the excavations were first made, some large trees grew over
the ruins; and the stump of one has been left directly over a party-wall
near the bath-room, for the sake of showing the thickness of the
superincumbent soil, which was here 38 inches.  In one small room, which,
after being cleared out, had not been roofed over, my sons observed the
hole of a worm passing through the rotten concrete, and a living worm was
found within the concrete.  In another open room worm-castings were seen
on the floor, over which some earth had by this means been deposited, and
here grass now grew.

_Brading_, _Isle of Wight_.—A fine Roman villa was discovered here in
1880; and by the end of October no less than 18 chambers had been more or
less cleared.  A coin dated 337 A.D. was found.  My son William visited
the place before the excavations were completed; and he informs me that
most of the floors were at first covered with much rubbish and fallen
stones, having their interstices completely filled up with mould,
abounding, as the workmen said, with worms, above which there was mould
without any stones.  The whole mass was in most places from 3 to above 4
ft. in thickness.  In one very large room the overlying earth was only 2
ft. 6 in. thick; and after this had been removed, so many castings were
thrown up between the tiles that the surface had to be almost daily
swept.  Most of the floors were fairly level.  The tops of the
broken-down walls were covered in some places by only 4 or 5 inches of
soil, so that they were occasionally struck by the plough, but in other
places they were covered by from 13 to 18 inches of soil.  It is not
probable that these walls could have been undermined by worms and
subsided, as they rested on a foundation of very hard red sand, into
which worms could hardly burrow.  The mortar, however, between the stones
of the walls of a hypocaust was found by my son to have been penetrated
by many worm-burrows.  The remains of this villa stand on land which
slopes at an angle of about 3°; and the land appears to have been long
cultivated.  Therefore no doubt a considerable quantity of fine earth has
been washed down from the upper parts of the field, and has largely aided
in the burial of these remains.

_Silchester_, _Hampshire_.—The ruins of this small Roman town have been
better preserved than any other remains of the kind in England.  A broken
wall, in most parts from 15 to 18 feet in height and about 1½ mile in
compass, now surrounds a space of about 100 acres of cultivated land, on
which a farm-house and a church stand. {187}  Formerly, when the weather
was dry, the lines of the buried walls could be traced by the appearance
of the crops; and recently very extensive excavations have been
undertaken by the Duke of Wellington, under the superintendence of the
late Rev. J. G. Joyce, by which means many large buildings have been
discovered.  Mr. Joyce made careful coloured sections, and measured the
thickness of each bed of rubbish, whilst the excavations were in
progress; and he has had the kindness to send me copies of several of
them.  When my sons Francis and Horace visited these ruins, he
accompanied them, and added his notes to theirs.

Mr. Joyce estimates that the town was inhabited by the Romans for about
three centuries; and no doubt much matter must have accumulated within
the walls during this long period.  It appears to have been destroyed by
fire, and most of the stones used in the buildings have since been
carried away.  These circumstances are unfavourable for ascertaining the
part which worms have played in the burial of the ruins; but as careful
sections of the rubbish overlying an ancient town have seldom or never
before been made in England, I will give copies of the most
characteristic portions of some of those made by Mr. Joyce.  They are of
too great length to be here introduced entire.

An east and west section, 30 ft. in length, was made across a room in the
Basilica, now called the Hall of the Merchants (Fig. 9).  The hard
concrete floor, still covered here and there with tesseræ, was found at 3
ft. beneath the surface of the field, which was here level.  On the floor
there were two large piles of charred wood, one alone of which is shown
in the part of the section here given.  This pile was covered by a thin
white layer of decayed stucco or plaster, above which was a mass,
presenting a singularly disturbed appearance, of broken tiles, mortar,
rubbish and fine gravel, together 27 inches in thickness.  Mr. Joyce
believes that the gravel was used in making the mortar or concrete, which
has since decayed, some of the lime probably having been dissolved.  The
disturbed state of the rubbish may have been due to its having been
searched for building stones.  This bed was capped by fine vegetable
mould, 9 inches in thickness.  From these facts we may conclude that the
Hall was burnt down, and that much rubbish fell on the floor, through and
from which the worms slowly brought up the mould, now forming the surface
of the level field.

 [Picture: Fig. 7: Section through one of the fallen Druidical stones at
Stonehenge.  Fig. 9: Section within a room in the Basilica at Silchester]

A section across the middle of another hall in the Basilica, 32 feet 6
inches in length, called the Ærarium, is shown in Fig. 10.  It appears
that we have here evidence of two fires, separated by an interval of
time, during which the 6 inches of “mortar and concrete with broken
tiles” was accumulated.  Beneath one of the layers of charred wood, a
valuable relic, a bronze eagle, was found; and this shows that the
soldiers must have deserted the place in a panic.  Owing to the death of
Mr. Joyce, I have not been able to ascertain beneath which of the two
layers the eagle was found.  The bed of rubble overlying the undisturbed
gravel originally formed, as I suppose, the floor, for it stands on a
level with that of a corridor, outside the walls of the Hall; but the
corridor is not shown in the section as here given.  The vegetable mould
was 16 inches thick in the thickest part; and the depth from the surface
of the field, clothed with herbage, to the undisturbed gravel, was 40
inches.

 [Picture: Fig. 10: Section within a hall in the Basilica of Silchester]

The section shown in Fig. 11 represents an excavation made in the middle
of the town, and is here introduced because the bed of “rich mould”
attained, according to Mr. Joyce, the unusual thickness of 20 inches.
Gravel lay at the depth of 48 inches from the surface; but it was not
ascertained whether this was in its natural state, or had been brought
here and had been rammed down, as occurs in some other places.

 [Picture: Fig. 11: Section in a block of buildings in the middle of the
                           town of Silchester]

The section shown in Fig. 12 was taken in the centre of the Basilica, and
though it was 5 feet in depth, the natural sub-soil was not reached.  The
bed marked “concrete” was probably at one time a floor; and the beds
beneath seem to be the remnants of more ancient buildings.  The vegetable
mould was here only 9 inches thick.  In some other sections, not copied,
we likewise have evidence of buildings having been erected over the ruins
of older ones.  In one case there was a layer of yellow clay of very
unequal thickness between two beds of débris, the lower one of which
rested on a floor with tesseræ.  The ancient broken walls appear to have
been sometimes roughly cut down to a uniform level, so as to serve as the
foundations for a temporary building; and Mr. Joyce suspects that some of
these buildings were wattled sheds, plastered with clay, which would
account for the above-mentioned layer of clay.

 [Picture: Fig. 12: Section in the centre of the Basilica at Silchester]

Turning now to the points which more immediately concern us.
Worm-castings were observed on the floors of several of the rooms, in one
of which the tesselation was unusually perfect.  The tesseræ here
consisted of little cubes of hard sandstone of about 1 inch, several of
which were loose or projected slightly above the general level.  One or
occasionally two open worm-burrows were found beneath all the loose
tesseræ.  Worms have also penetrated the old walls of these ruins.  A
wall, which had just been exposed to view during the excavations then in
progress, was examined; it was built of large flints, and was 18 inches
in thickness.  It appeared sound, but when the soil was removed from
beneath, the mortar in the lower part was found to be so much decayed
that the flints fell apart from their own weight.  Here, in the middle of
the wall, at a depth of 29 inches beneath the old floor and of 49½ inches
beneath the surface of the field, a living worm was found, and the mortar
was penetrated by several burrows.

A second wall was exposed to view for the first time, and an open burrow
was seen on its broken summit.  By separating the flints this burrow was
traced far down in the interior of the wall; but as some of the flints
cohered firmly, the whole mass was disturbed in pulling down the wall,
and the burrow could not be traced to the bottom.  The foundations of a
third wall, which appeared quite sound, lay at a depth of 4 feet beneath
one of the floors, and of course at a considerably greater depth beneath
the level of the ground.  A large flint was wrenched out of the wall at
about a foot from the base, and this required much force, as the mortar
was sound; but behind the flint in the middle of the wall, the mortar was
friable, and here there were worm-burrows.  Mr. Joyce and my sons were
surprised at the blackness of the mortar in this and in several other
cases, and at the presence of mould in the interior of the walls.  Some
may have been placed there by the old builders instead of mortar; but we
should remember that worms line their burrows with black humus.  Moreover
open spaces would almost certainly have been occasionally left between
the large irregular flints; and these spaces, we may feel sure, would be
filled up by the worms with their castings, as soon as they were able to
penetrate the wall.  Rain-water, oozing down the burrows would also carry
fine dark-coloured particles into every crevice.  Mr. Joyce was at first
very sceptical about the amount of work which I attributed to worms; but
he ends his notes with reference to the last-mentioned wall by saying,
“This case caused me more surprise and brought more conviction to me than
any other.  I should have said, and did say, that it was quite impossible
such a wall could have been penetrated by earth-worms.”

In almost all the rooms the pavement has sunk considerably, especially
towards the middle; and this is shown in the three following sections.
The measurements were made by stretching a string tightly and
horizontally over the floor.  The section, Fig. 13, was taken from north
to south across a room, 18 feet 4 inches in length, with a nearly perfect
pavement, next to the “Red Wooden Hut.”  In the northern half, the
subsidence amounted to 5¾ inches beneath the level of the floor as it now
stands close to the walls; and it was greater in the northern than in the
southern half; but, according to Mr. Joyce, the entire pavement has
obviously subsided.  In several places, the tesseræ appeared as if drawn
a little away from the walls; whilst in other places they were still in
close contact with them.

 [Picture: Fig. 14: A north and south section through the subsided floor
                              of a corridor]

In Fig. 14, we see a section across the paved floor of the southern
corridor or ambulatory of a quadrangle, in an excavation made near “The
Spring.”  The floor is 7 feet 9 inches wide, and the broken-down walls
now project only ¾ of an inch above its level.  The field, which was in
pasture, here sloped from north to south, at an angle of 30°, 40'.  The
nature of the ground at some little distance on each side of the corridor
is shown in the section.  It consisted of earth full of stones and other
débris, capped with dark vegetable mould which was thicker on the lower
or southern than on the northern side.  The pavement was nearly level
along lines parallel to the side-walls, but had sunk in the middle as
much as 7¾ inches.

A small room at no great distance from that represented in Fig. 13, had
been enlarged by the Roman occupier on the southern side, by an addition
of 5 feet 4 inches in breadth.  For this purpose the southern wall of the
house had been pulled down, but the foundations of the old wall had been
left buried at a little depth beneath the pavement of the enlarged room.
Mr. Joyce believes that this buried wall must have been built before the
reign of Claudius II., who died 270 A.D.  We see in the accompanying
section, Fig. 15, that the tesselated pavement has subsided to a less
degree over the buried wall than elsewhere; so that a slight convexity or
protuberance here stretched in a straight line across the room.  This led
to a hole being dug, and the buried wall was thus discovered.

          [Picture: Fig. 15: Section through the subsided floor]

We see in these three sections, and in several others not given, that the
old pavements have sunk or sagged considerably.  Mr. Joyce formerly
attributed this sinking solely to the slow settling of the ground.  That
there has been some settling is highly probable, and it may be seen in
Fig. 15 that the pavement for a width of 5 feet over the southern
enlargement of the room, which must have been built on fresh ground, has
sunk a little more than on the old northern side.  But this sinking may
possibly have had no connection with the enlargement of the room; for in
Fig. 13 one half of the pavement has subsided more than the other half
without any assignable cause.  In a bricked passage to Mr. Joyce’s own
house, laid down only about six years ago, the same kind of sinking has
occurred as in the ancient buildings.  Nevertheless it does not appear
probable that the whole amount of sinking can be thus accounted for.  The
Roman builders excavated the ground to an unusual depth for the
foundations of their walls, which were thick and solid; it is therefore
hardly credible that they should have been careless about the solidity of
the bed on which their tesselated and often ornamented pavements were
laid.  The sinking must, as it appears to me, be attributed in chief part
to the pavement having been undermined by worms, which we know are still
at work.  Even Mr. Joyce at last admitted that this could not have failed
to have produced a considerable effect.  Thus also the large quantity of
fine mould overlying the pavements can be accounted for, the presence of
which would otherwise be inexplicable.  My sons noticed that in one room
in which the pavement had sagged very little, there was an unusually
small amount of overlying mould.

As the foundations of the walls generally lie at a considerable depth,
they will either have not subsided at all through the undermining action
of worms, or they will have subsided much less than the floor.  This
latter result would follow from worms not often working deep down beneath
the foundations; but more especially from the walls not yielding when
penetrated by worms, whereas the successively formed burrows in a mass of
earth, equal to one of the walls in depth and thickness, would have
collapsed many times since the desertion of the ruins, and would
consequently have shrunk or subsided.  As the walls cannot have sunk much
or at all, the immediately adjoining pavement from adhering to them will
have been prevented from subsiding; and thus the present curvature of the
pavement is intelligible.

The circumstance which has surprised me most with respect to Silchester
is that during the many centuries which have elapsed since the old
buildings were deserted, the vegetable mould has not accumulated over
them to a greater thickness than that here observed.  In most places it
is only about 9 inches in thickness, but in some places 12 or even more
inches.  In Fig. 11, it is given as 20 inches, but this section was drawn
by Mr. Joyce before his attention was particularly called to this
subject.  The land enclosed within the old walls is described as sloping
slightly to the south; but there are parts which, according to Mr. Joyce,
are nearly level, and it appears that the mould is here generally thicker
than elsewhere.  The surface slopes in other parts from west to east, and
Mr. Joyce describes one floor as covered at the western end by rubbish
and mould to a thickness of 28½ inches, and at the eastern end by a
thickness of only 11½ inches.  A very slight slope suffices to cause
recent castings to flow downwards during heavy rain, and thus much earth
will ultimately reach the neighbouring rills and streams and be carried
away.  By this means, the absence of very thick beds of mould over these
ancient ruins may, as I believe, be explained.  Moreover most of the land
here has long been ploughed, and this would greatly aid the washing away
of the finer earth during rainy weather.

The nature of the beds immediately beneath the vegetable mould in some of
the sections is rather perplexing.  We see, for instance, in the section
of an excavation in a grass meadow (Fig. 14), which sloped from north to
south at an angle of 3° 40', that the mould on the upper side is only six
inches and on the lower side nine inches in thickness.  But this mould
lies on a mass (25½ inches in thickness on the upper side) “of dark brown
mould,” as described by Mr. Joyce, “thickly interspersed with small
pebbles and bits of tiles, which present a corroded or worn appearance.”
The state of this dark-coloured earth is like that of a field which has
long been ploughed, for the earth thus becomes intermingled with stones
and fragments of all kinds which have been much exposed to the weather.
If during the course of many centuries this grass meadow and the other
now cultivated fields have been at times ploughed, and at other times
left as pasture, the nature of the ground in the above section is
rendered intelligible.  For worms will continually have brought up fine
earth from below, which will have been stirred up by the plough whenever
the land was cultivated.  But after a time a greater thickness of fine
earth will thus have been accumulated than could be reached by the
plough; and a bed like the 25½-inch mass, in Fig. 14, will have been
formed beneath the superficial mould, which latter will have been brought
to the surface within more recent times, and have been well sifted by the
worms.

_Wroxeter_, _Shropshire_.—The old Roman city of Uriconium was founded in
the early part of the second century, if not before this date; and it was
destroyed, according to Mr. Wright, probably between the middle of the
fourth and fifth century.  The inhabitants were massacred, and skeletons
of women were found in the hypocausts.  Before the year 1859, the sole
remnant of the city above ground, was a portion of a massive wall about
20 ft. in height.  The surrounding land undulates slightly, and has long
been under cultivation.  It had been noticed that the corn-crops ripened
prematurely in certain narrow lines, and that the snow remained unmelted
in certain places longer than in others.  These appearances led, as I was
informed, to extensive excavations being undertaken.  The foundations of
many large buildings and several streets have thus been exposed to view.
The space enclosed within the old walls is an irregular oval, about 1¾
mile in length.  Many of the stones or bricks used in the buildings must
have been carried away; but the hypocausts, baths, and other underground
buildings were found tolerably perfect, being filled with stones, broken
tiles, rubbish and soil.  The old floors of various rooms were covered
with rubble.  As I was anxious to know how thick the mantle of mould and
rubbish was, which had so long concealed these ruins, I applied to Dr. H.
Johnson, who had superintended the excavations; and he, with the greatest
kindness, twice visited the place to examine it in reference to my
questions, and had many trenches dug in four fields which had hitherto
been undisturbed.  The results of his observations are given in the
following Table.  He also sent me specimens of the mould, and answered,
as far as he could, all my questions.



MEASUREMENTS BY DR. H. JOHNSON OF THE THICKNESS OF THE VEGETABLE MOULD
OVER THE ROMAN RUINS AT WROXETER.


               Trenches dug in a field called “Old Works.”

                                    Thickness of mould in inches.
1.  At a depth of 36 inches                                         20
undisturbed sand was reached
2.  At a depth of 33 inches                                         21
concrete was reached
3. At a depth of 9 inches                                            9
concrete was reached

Trenches dug in a field called “Shop Leasows;” this is the highest field
within the old walls, and slopes down from a sub-central point on all
sides at about an angle of 2°.

                                    Thickness of mould in inches.
4.  Summit of field, trench 45                                      40
inches deep
5.  Close to summit of field,                                       26
trench 36 inches deep
6.  Close to summit of field,                                       28
trench 28 inches deep
7.  Near summit of field, trench                                    24
36 inches deep
8.  Near summit of field, trench                                    24
at one end 39 inches deep; the
mould here graduated into the
underlying undisturbed sand, and
its thickness (24 inches) is
somewhat arbitrary.  At the other
end of the trench, a causeway was
encountered at a depth of only 7
inches, and the mould was here
only 7 inches thick
9.  Trench close to the last, 28                                    24
inches in depth
10.  Lower part of same field,                                      15
trench 30 inches deep
11.  Lower part of same field,                                      17
trench 31 inches deep
12.  Lower part of same field,                                      28
trench 36 inches deep, at which
depth undisturbed sand was
reached
13.  In another part of same                                        9½
field, trench 9½ inches deep
stopped by concrete
14.  In another part of same                                         9
field, trench 9 inches deep,
stopped by concrete
15.  In another part of the same                                    16
field, trench 24 inches deep,
when sand was reached
16.  In another part of same                                        13
field, trench 30 inches deep,
when stones were reached; at one
end of the trench mould 12
inches, at the other end 14
inches thick

Small field between “Old Works” and “Shop Leasows,” I believe nearly as
high as the upper part of the latter field.

                                    Thickness of mould in inches.
17.  Trench 26 inches deep                                          24
18.  Trench 10 inches deep, and                                     10
then came upon a causeway
19.  Trench 34 inches deep                                          30
20. Trench 31 inches deep                                           31

Field on the western side of the space enclosed within the old walls.

                                    Thickness of mould in inches.
21.  Trench 28 inches deep, when                                    16
undisturbed sand was reached
22.  Trench 29 inches deep, when                                    15
undisturbed sand was reached
23.  Trench 14 inches deep, and                                     14
then came upon a building

Dr. Johnson distinguished as mould the earth which differed, more or less
abruptly, in its dark colour and in its texture from the underlying sand
or rubble.  In the specimens sent to me, the mould resembled that which
lies immediately beneath the turf in old pasture-land, excepting that it
often contained small stones, too large to have passed through the bodies
of worms.  But the trenches above described were dug in fields, none of
which were in pasture, and all had been long cultivated.  Bearing in mind
the remarks made in reference to Silchester on the effects of
long-continued culture, combined with the action of worms in bringing up
the finer particles to the surface, the mould, as so designated by Dr.
Johnson, seems fairly well to deserve its name.  Its thickness, where
there was no causeway, floor or walls beneath, was greater than has been
elsewhere observed, namely, in many places above 2 ft., and in one spot
above 3 ft.  The mould was thickest on and close to the nearly level
summit of the field called “Shop Leasows,” and in a small adjoining
field, which, as I believe, is of nearly the same height.  One side of
the former field slopes at an angle of rather above 2°, and I should have
expected that the mould, from being washed down during heavy rain, would
have been thicker in the lower than in the upper part; but this was not
the case in two out of the three trenches here dug.

In many places, where streets ran beneath the surface, or where old
buildings stood, the mould was only 8 inches in thickness; and Dr.
Johnson was surprised that in ploughing the land, the ruins had never
been struck by the plough as far as he had heard.  He thinks that when
the land was first cultivated the old walls were perhaps intentionally
pulled down, and that hollow places were filled up.  This may have been
the case; but if after the desertion of the city the land was left for
many centuries uncultivated, worms would have brought up enough fine
earth to have covered the ruins completely; that is if they had subsided
from having been undermined.  The foundations of some of the walls, for
instance those of the portion still standing about 20 feet above the
ground, and those of the marketplace, lie at the extraordinary depth of
14 feet; but it is highly improbable that the foundations were generally
so deep.  The mortar employed in the buildings must have been excellent,
for it is still in parts extremely hard.  Wherever walls of any height
have been exposed to view, they are, as Dr. Johnson believes, still
perpendicular.  The walls with such deep foundations cannot have been
undermined by worms, and therefore cannot have subsided, as appears to
have occurred at Abinger and Silchester.  Hence it is very difficult to
account for their being now completely covered with earth; but how much
of this covering consists of vegetable mould and how much of rubble I do
not know.  The market-place, with the foundations at a depth of 14 feet,
was covered up, as Dr. Johnson believes, by between 6 and 24 inches of
earth.  The tops of the broken-down walls of a caldarium or bath, 9 feet
in depth, were likewise covered up with nearly 2 feet of earth.  The
summit of an arch, leading into an ash-pit 7 feet in depth, was covered
up with not more than 8 inches of earth.  Whenever a building which has
not subsided is covered with earth, we must suppose, either that the
upper layers of stone have been at some time carried away by man, or that
earth has since been washed down during heavy rain, or blown down during
storms, from the adjoining land; and this would be especially apt to
occur where the land has long been cultivated.  In the above cases the
adjoining land is somewhat higher than the three specified sites, as far
as I can judge by maps and from information given me by Dr. Johnson.  If;
however, a great pile of broken stones, mortar, plaster, timber and ashes
fell over the remains of any building, their disintegration in the course
of time, and the sifting action of worms, would ultimately conceal the
whole beneath fine earth.

                                * * * * *

_Conclusion_.—The cases given in this chapter show that worms have played
a considerable part in the burial and concealment of several Roman and
other old buildings in England; but no doubt the washing down of soil
from the neighbouring higher lands, and the deposition of dust, have
together aided largely in the work of concealment.  Dust would be apt to
accumulate wherever old broken-down walls projected a little above the
then existing surface and thus afforded some shelter.  The floors of the
old rooms, halls and passages have generally sunk, partly from the
settling of the ground, but chiefly from having been undermined by worms;
and the sinking has commonly been greater in the middle than near the
walls.  The walls themselves, whenever their foundations do not lie at a
great depth, have been penetrated and undermined by worms, and have
consequently subsided.  The unequal subsidence thus caused, probably
explains the great cracks which may be seen in many ancient walls, as
well as their inclination from the perpendicular.




CHAPTER V.
THE ACTION OF WORMS IN THE DENUDATION OF THE LAND.


Evidence of the amount of denudation which the land has
undergone—Sub-aerial denudation—The deposition of dust—Vegetable mould,
its dark colour and fine texture largely due to the action of worms—The
disintegration of rocks by the humus-acids—Similar acids apparently
generated within the bodies of worms—The action of these acids
facilitated by the continued movement of the particles of earth—A thick
bed of mould checks the disintegration of the underlying soil and rocks.
Particles of stone worn or triturated in the gizzards of worms—Swallowed
stones serve as mill-stones—The levigated state of the castings—Fragments
of brick in the castings over ancient buildings well rounded.  The
triturating power of worms not quite insignificant under a geological
point of view.

NO one doubts that our world at one time consisted of crystalline rocks,
and that it is to their disintegration through the action of air, water,
changes of temperature, rivers, waves of the sea, earthquakes and
volcanic outbursts, that we owe our sedimentary formations.  These after
being consolidated and sometimes recrystallized, have often been again
disintegrated.  Denudation means the removal of such disintegrated matter
to a lower level.  Of the many striking results due to the modern
progress of geology there are hardly any more striking than those which
relate to denudation.  It was long ago seen that there must have been an
immense amount of denudation; but until the successive formations were
carefully mapped and measured, no one fully realised how great was the
amount.  One of the first and most remarkable memoirs ever published on
this subject was that by Ramsay, {210} who in 1846 showed that in Wales
from 9000 to 11,000 feet in thickness of solid rock had been stripped off
large tracks of country.  Perhaps the plainest evidence of great
denudation is afforded by faults or cracks, which extend for many miles
across certain districts, with the strata on one side raised even ten
thousand feet above the corresponding strata on the opposite side; and
yet there is not a vestige of this gigantic displacement visible on the
surface of the land.  A huge pile of rock has been planed away on one
side and not a remnant left.

Until the last twenty or thirty years, most geologists thought that the
waves of the sea were the chief agents in the work of denudation; but we
may now feel sure that air and rain, aided by streams and rivers, are
much more powerful agents,—that is if we consider the whole area of the
land.  The long lines of escarpment which stretch across several parts of
England were formerly considered to be undoubtedly ancient coast-lines;
but we now know that they stand up above the general surface merely from
resisting air, rain and frost better than the adjoining formations.  It
has rarely been the good fortune of a geologist to bring conviction to
the minds of his fellow-workers on a disputed point by a single memoir;
but Mr. Whitaker, of the Geological Survey of England, was so fortunate
when, in 1867, he published his paper “On sub-aerial Denudation, and on
Cliffs and Escarpments of the Chalk.” {211}  Before this paper appeared,
Mr. A. Tylor had adduced important evidence on sub-aerial denudation, by
showing that the amount of matter brought down by rivers must infallibly
lower the level of their drainage basins by many feet in no immense lapse
of time.  This line of argument has since been followed up in the most
interesting manner by Archibald Geikie, Croll and others, in a series of
valuable memoirs. {212}  For the sake of those who have never attended to
this subject, a single instance may be here given, namely, that of the
Mississippi, which is chosen because the amount of sediment brought down
by this great river has been investigated with especial care by order of
the United States Government.  The result is, as Mr. Croll shows, that
the mean level of its enormous area of drainage must be lowered 1/4566 of
a foot annually, or 1 foot in 4566 years.  Consequently, taking the best
estimate of the mean height of the North American continent, viz. 748
feet, and looking to the future, the whole of the great Mississippi basin
will be washed away, and “brought down to the sea-level in less than
4,500,000 years, if no elevation of the land takes place.”  Some rivers
carry down much more sediment relatively to their size, and some much
less than the Mississippi.

Disintegrated matter is carried away by the wind as well as by running
water.  During volcanic outbursts much rock is triturated and is thus
widely dispersed; and in all arid countries the wind plays an important
part in the removal of such matter.  Wind-driven sand also wears down the
hardest rocks.  I have shown {213} that during four months of the year a
large quantity of dust is blown from the north-western shores of Africa,
and falls on the Atlantic over a space of 1600 miles in latitude, and for
a distance of from 300 to 600 miles from the coast.  But dust has been
seen to fall at a distance of 1030 miles from the shores of Africa.
During a stay of three weeks at St. Jago in the Cape Verde Archipelago,
the atmosphere was almost always hazy, and extremely fine dust coming
from Africa was continually falling.  In some of this dust which fell in
the open ocean at a distance of between 330 and 380 miles from the
African coast, there were many particles of stone, about 1/1000 of an
inch square.  Nearer to the coast the water has been seen to be so much
discoloured by the falling dust, that a sailing vessel left a track
behind her.  In countries, like the Cape Verde Archipelago, where it
seldom rains and there are no frosts, the solid rock nevertheless
disintegrates; and in conformity with the views lately advanced by a
distinguished Belgian geologist, De Koninck, such disintegration may be
attributed in chief part to the action of the carbonic and nitric acids,
together with the nitrates and nitrites of ammonia, dissolved in the dew.

In all humid, even moderately humid, countries, worms aid in the work of
denudation in several ways.  The vegetable mould which covers, as with a
mantle, the surface of the land, has all passed many times through their
bodies.  Mould differs in appearance from the subsoil only in its dark
colour, and in the absence of fragments or particles of stone (when such
are present in the subsoil), larger than those which can pass through the
alimentary canal of a worm.  This sifting of the soil is aided, as has
already been remarked, by burrowing animals of many kinds, especially by
ants.  In countries where the summer is long and dry, the mould in
protected places must be largely increased by dust blown from other and
more exposed places.  For instance, the quantity of dust sometimes blown
over the plains of La Plata, where there are no solid rocks, is so great,
that during the “gran seco,” 1827 to 1830, the appearance of the land,
which is here unenclosed, was so completely changed that the inhabitants
could not recognise the limits of their own estates, and endless lawsuits
arose.  Immense quantities of dust are likewise blown about in Egypt and
in the south of France.  In China, as Richthofen maintains, beds
appearing like fine sediment, several hundred feet in thickness and
extending over an enormous area, owe their origin to dust blown from the
high lands of central Asia. {215}  In humid countries like Great Britain,
as long as the land remains in its natural state clothed with vegetation,
the mould in any one place can hardly be much increased by dust; but in
its present condition, the fields near high roads, where there is much
traffic, must receive a considerable amount of dust, and when fields are
harrowed during dry and windy weather, clouds of dust may be seen to be
blown away.  But in all these cases the surface-soil is merely
transported from one place to another.  The dust which falls so thickly
within our houses consists largely of organic matter, and if spread over
the land would in time decay and disappear almost entirely.  It appears,
however, from recent observations on the snow-fields of the Arctic
regions, that some little meteoric dust of extra mundane origin is
continually falling.

The dark colour of ordinary mould is obviously due to the presence of
decaying organic matter, which, however, is present in but small
quantities.  The loss of weight which mould suffers when heated to
redness seems to be in large part due to water in combination being
dispelled.  In one sample of fertile mould the amount of organic matter
was ascertained to be only 1.76 per cent.; in some artificially prepared
soil it was as much as 5.5 per cent., and in the famous black soil of
Russia from 5 to even 12 per cent. {217a}  In leaf-mould formed
exclusively by the decay of leaves the amount is much greater, and in
peat the carbon alone sometimes amounts to 64 per cent.; but with these
latter cases we are not here concerned.  The carbon in the soil tends
gradually to oxidise and to disappear, except where water accumulates and
the climate is cool; {217b} so that in the oldest pasture-land there is
no great excess of organic matter, notwithstanding the continued decay of
the roots and the underground stems of plants, and the occasional
addition of manure.  The disappearance of the organic matter from mould
is probably much aided by its being brought again and again to the
surface in the castings of worms.

Worms, on the other hand, add largely to the organic matter in the soil
by the astonishing number of half-decayed leaves which they draw into
their burrows to a depth of 2 or 3 inches.  They do this chiefly for
obtaining food, but partly for closing the mouths of their burrows and
for lining the upper part.  The leaves which they consume are moistened,
torn into small shreds, partially digested, and intimately commingled
with earth; and it is this process which gives to vegetable mould its
uniform dark tint.  It is known that various kinds of acids are generated
by the decay of vegetable matter; and from the contents of the intestines
of worms and from their castings being acid, it seems probable that the
process of digestion induces an analogous chemical change in the
swallowed, triturated, and half-decayed leaves.  The large quantity of
carbonate of lime secreted by the calciferous glands apparently serves to
neutralise the acids thus generated; for the digestive fluid of worms
will not act unless it be alkaline.  As the contents of the upper part of
their intestines are acid, the acidity can hardly be due to the presence
of uric acid.  We may therefore conclude that the acids in the alimentary
canal of worms are formed during the digestive process; and that probably
they are nearly of the same nature as those in ordinary mould or humus.
The latter are well known to have the power of de-oxidising or dissolving
per-oxide of iron, as may be seen wherever peat overlies red sand, or
where a rotten root penetrates such sand.  Now I kept some worms in a pot
filled with very fine reddish sand, consisting of minute particles of
silex coated with the red oxide of iron; and the burrows, which the worms
made through this sand, were lined or coated in the usual manner with
their castings, formed of the sand mingled with their intestinal
secretions and the refuse of the digested leaves; and this sand had
almost wholly lost its red colour.  When small portions of it were placed
under the microscope, most of the grains were seen to be transparent and
colourless, owing to the dissolution of the oxide; whilst almost all the
grains taken from other parts of the pot were coated with the oxide.
Acetic acid produced hardly any effect on his sand; and even
hydrochloric, nitric and sulphuric acids, diluted as in the
Pharmacopoeia, produced less effect than did the acids in the intestines
of the worms.

Mr. A. A. Julien has lately collected all the extant information about
the acids generated in humus, which, according to some chemists, amount
to more than a dozen different kinds.  These acids, as well as their acid
salts (i.e., in combination with potash, soda, and ammonia), act
energetically on carbonate of lime and on the oxides of iron.  It is also
known that some of these acids, which were called long ago by Thénard
azohumic, are enabled to dissolve colloid silica in proportion to the
nitrogen which they contain. {220}  In the formation of these latter
acids worms probably afford some aid, for Dr. H. Johnson informs me that
by Nessler’s test he found 0.018 per cent. of ammonia in their castings.

It may be here added that I have recently been informed by Dr. Gilbert
“that several square yards on his lawn were swept clean, and after two or
three weeks all the worm-castings on the space were collected and dried.
These were found to contain 0.35 of nitrogen.  This is from two to three
times as much as we find in our ordinary arable surface-soil; more than
in our ordinary pasture surface-soil; but less than in rich
kitchen-garden mould.  Supposing a quantity of castings equal to 10 tons
in the dry state were annually deposited on an acre, this would represent
a manuring of 78 lbs. of nitrogen per acre per annum; and this is very
much more than the amount of nitrogen in the annual yield of hay per
acre, if raised without any nitrogenous manure.  Obviously, so far as the
nitrogen in the castings is derived from surface-growth or from
surface-soil, it is not a gain to the latter; but so far as it is derived
from below, it is a gain.”

The several humus-acids, which appear, as we have just seen, to be
generated within the bodies of worms during the digestive process, and
their acid salts, play a highly important part, according to the recent
observations of Mr. Julien, in the disintegration of various kinds of
rocks.  It has long been known that the carbonic acid, and no doubt
nitric and nitrous acids, which are present in rain-water, act in like
manner.  There is, also, a great excess of carbonic acid in all soils,
especially in rich soils, and this is dissolved by the water in the
ground.  The living roots of plants, moreover, as Sachs and others have
shown, quickly corrode and leave their impressions on polished slabs of
marble, dolomite and phosphate of lime.  They will attack even basalt and
sandstone. {222}  But we are not here concerned with agencies which are
wholly independent of the action of worms.

The combination of any acid with a base is much facilitated by agitation,
as fresh surfaces are thus continually brought into contact.  This will
be thoroughly effected with the particles of stone and earth in the
intestines of worms, during the digestive process; and it should be
remembered that the entire mass of the mould over every field, passes, in
the course of a few years, through their alimentary canals.  Moreover as
the old burrows slowly collapse, and as fresh castings are continually
brought to the surface, the whole superficial layer of mould slowly
revolves or circulates; and the friction of the particles one with
another will rub off the finest films of disintegrated matter as soon as
they are formed.  Through these several means, minute fragments of rocks
of many kinds and mere particles in the soil will be continually exposed
to chemical decomposition; and thus the amount of soil will tend to
increase.

As worms line their burrows with their castings, and as the burrows
penetrate to a depth of 5 or 6, or even more feet, some small amount of
the humus-acids will be carried far down, and will there act on the
underlying rocks and fragments of rock.  Thus the thickness of the soil,
if none be removed from the surface, will steadily though slowly tend to
increase; but the accumulation will after a time delay the disintegration
of the underlying rocks and of the more deeply seated particles.  For the
humus-acids which are generated chiefly in the upper layer of vegetable
mould, are extremely unstable compounds, and are liable to decomposition
before they reach any considerable depth. {223}  A thick bed of overlying
soil will also check the downward extension of great fluctuations of
temperature, and in cold countries will check the powerful action of
frost.  The free access of air will likewise be excluded.  From these
several causes disintegration would be almost arrested, if the overlying
mould were to increase much in thickness, owing to none or little being
removed from the surface. {224a}  In my own immediate neighbourhood we
have a curious proof how effectually a few feet of clay checks some
change which goes on in flints, lying freely exposed; for the large ones
which have lain for some time on the surface of ploughed fields cannot be
used for building; they will not cleave properly, and are said by the
workmen to be rotten. {224b}  It is therefore necessary to obtain flints
for building purposes from the bed of red clay overlying the chalk (the
residue of its dissolution by rain-water) or from the chalk itself.

Not only do worms aid directly in the chemical disintegration of rocks,
but there is good reason to believe that they likewise act in a direct
and mechanical manner on the smaller particles.  All the species which
swallow earth are furnished with gizzards; and these are lined with so
thick a chitinous membrane, that Perrier speaks of it, {225a} as “une
véritable armature.”  The gizzard is surrounded by powerful transverse
muscles, which, according to Claparède, are about ten times as thick as
the longitudinal ones; and Perrier saw them contracting energetically.
Worms belonging to one genus, Digaster, have two distinct but quite
similar gizzards; and in another genus, Moniligaster, the second gizzard
consists of four pouches, one succeeding the other, so that it may almost
be said to have five gizzards. {225b}  In the same manner as gallinaceous
and struthious birds swallow stones to aid in the trituration of their
food, so it appears to be with terricolous worms.  The gizzards of
thirty-eight of our common worms were opened, and in twenty-five of them
small stones or grains of sand, sometimes together with the hard
calcareous concretions formed within the anterior calciferous glands,
were found, and in two others concretions alone.  In the gizzards of the
remaining worms there were no stones; but some of these were not real
exceptions, as the gizzards were opened late in the autumn, when the
worms had ceased to feed and their gizzards were quite empty. {226}

When worms make their burrows through earth abounding with little stones,
no doubt many will be unavoidably swallowed; but it must not be supposed
that this fact accounts for the frequency with which stones and sand are
found in their gizzards.  For beads of glass and fragments of brick and
of hard tiles were scattered over the surface of the earth, in pots in
which worms were kept and had already made their burrows; and very many
of these beads and fragments were picked up and swallowed by the worms,
for they were found in their castings, intestines, and gizzards.  They
even swallowed the coarse red dust, formed by the pounding of the tiles.
Nor can it be supposed that they mistook the beads and fragments for
food; for we have seen that their taste is delicate enough to distinguish
between different kinds of leaves.  It is therefore manifest that they
swallow hard objects, such as bits of stone, beads of glass and angular
fragments of bricks or tiles for some special purpose; and it can hardly
be doubted that this is to aid their gizzards in crushing and grinding
the earth, which they so largely consume.  That such hard objects are not
necessary for crushing leaves, may be inferred from the fact that certain
species, which live in mud or water and feed on dead or living vegetable
matter, but which do not swallow earth, are not provided with gizzards,
{227} and therefore cannot have the power of utilising stones.

During the grinding process, the particles of earth must be rubbed
against one another, and between the stones and the tough lining membrane
of the gizzard.  The softer particles will thus suffer some attrition,
and will perhaps even be crushed.  This conclusion is supported by the
appearance of freshly ejected castings, for these often reminded me of
the appearance of paint which has just been ground by a workman between
two flat stones.  Morren remarks that the intestinal canal is “impleta
tenuissimâ terrâ, veluti in pulverem redactâ.” {228a}  Perrier also
speaks of “l’état de pâte excessivement fine à laquelle est réduite la
terre qu’ils rejettent,” &c. {228b}

As the amount of trituration which the particles of earth undergo in the
gizzards of worms possesses some interest (as we shall hereafter see), I
endeavoured to obtain evidence on this head by carefully examining many
of the fragments which had passed through their alimentary canals.  With
worms living in a state of nature, it is of course impossible to know how
much the fragments may have been worn before they were swallowed.  It is,
however, clear that worms do not habitually select already rounded
particles, for sharply angular bits of flint and of other hard rocks were
often found in their gizzards or intestines.  On three occasions sharp
spines from the stems of rose-bushes were thus found.  Worms kept in
confinement repeatedly swallowed angular fragments of hard tile, coal,
cinders, and even the sharpest fragments of glass.  Gallinaceous and
struthious birds retain the same stones in their gizzards for a long
time, which thus become well rounded; but this does not appear to be the
case with worms, judging from the large number of the fragments of tiles,
glass beads, stones, &c., commonly found in their castings and
intestines.  So that unless the same fragments were to pass repeatedly
through their gizzards, visible signs of attrition in the fragments could
hardly be expected, except perhaps in the case of very soft stones.

I will now give such evidence of attrition as I have been able to
collect.  In the gizzards of some worms dug out of a thin bed of mould
over the chalk, there were many well-rounded small fragments of chalk,
and two fragments of the shells of a land-mollusc (as ascertained by
their microscopical structure), which latter were not only rounded but
somewhat polished.  The calcareous concretions formed in the calciferous
glands, which are often found in their gizzards, intestines, and
occasionally in their castings, when of large size, sometimes appeared to
have been rounded; but with all calcareous bodies the rounded appearance
may be partly or wholly due to their corrosion by carbonic acid and the
humus-acids.  In the gizzards of several worms collected in my kitchen
garden near a hothouse, eight little fragments of cinders were found, and
of these, six appeared more or less rounded, as were two bits of brick;
but some other bits were not at all rounded.  A farm-road near Abinger
Hall had been covered seven years before with brick-rubbish to the depth
of about 6 inches; turf had grown over this rubbish on both sides of the
road for a width of 18 inches, and on this turf there were innumerable
castings.  Some of them were coloured of a uniform red owing to the
presence of much brick-dust, and they contained many particles of brick
and of hard mortar from 1 to 3 mm. in diameter, most of which were
plainly rounded; but all these particles may have been rounded before
they were protected by the turf and were swallowed, like those on the
bare parts of the road which were much worn.  A hole in a pasture-field
had been filled up with brick-rubbish at the same time, viz., seven years
ago, and was now covered with turf; and here the castings contained very
many particles of brick, all more or less rounded; and this
brick-rubbish, after being shot into the hole, could not have undergone
any attrition.  Again, old bricks very little broken, together with
fragments of mortar, were laid down to form walks, and were then covered
with from 4 to 6 inches of gravel; six little fragments of brick were
extracted from castings collected on these walks, three of which were
plainly worn.  There were also very many particles of hard mortar, about
half of which were well rounded; and it is not credible that these could
have suffered so much corrosion from the action of carbonic acid in the
course of only seven years.

Much better evidence of the attrition of hard objects in the gizzards of
worms, is afforded by the state of the small fragments of tiles or
bricks, and of concrete in the castings thrown up where ancient buildings
once stood.  As all the mould covering a field passes every few years
through the bodies of worms, the same small fragments will probably be
swallowed and brought to the surface many times in the course of
centuries.  It should be premised that in the several following cases,
the finer matter was first washed away from the castings, and then _all_
the particles of bricks, tiles and concrete were collected without any
selection, and were afterwards examined.  Now in the castings ejected
between the tesseræ on one of the buried floors of the Roman villa at
Abinger, there were many particles (from ½ to 2 mm. in diameter) of tiles
and concrete, which it was impossible to look at with the naked eye or
through a strong lens, and doubt for a moment that they had almost all
undergone much attrition.  I speak thus after having examined small
water-worn pebbles, formed from Roman bricks, which M. Henri de Saussure
had the kindness to send me, and which he had extracted from sand and
gravel beds, deposited on the shores of the Lake of Geneva, at a former
period when the water stood at about two metres above its present level.
The smallest of these water-worn pebbles of brick from Geneva resembled
closely many of those extracted from the gizzards of worms, but the
larger ones were somewhat smoother.

Four castings found on the recently uncovered, tesselated floor of the
great room in the Roman villa at Brading, contained many particles of
tile or brick, of mortar, and of hard white cement; and the majority of
these appeared plainly worn.  The particles of mortar, however, seemed to
have suffered more corrosion than attrition, for grains of silex often
projected from their surfaces.  Castings from within the nave of Beaulieu
Abbey, which was destroyed by Henry VIII., were collected from a level
expanse of turf, overlying the buried tesselated pavement, through which
worm-burrows passed; and these castings contained innumerable particles
of tiles and bricks, of concrete and cement, the majority of which had
manifestly undergone some or much attrition.  There were also many minute
flakes of a micaceous slate, the points of which were rounded.  If the
above supposition, that in all these cases the same minute fragments have
passed several times through the gizzards of worms, be rejected,
notwithstanding its inherent probability, we must then assume that in all
the above cases the many rounded fragments found in the castings had all
accidentally undergone much attrition before they were swallowed; and
this is highly improbable.

On the other hand it must be stated that fragments of ornamental tiles,
somewhat harder than common tiles or bricks, which had been swallowed
only once by worms kept in confinement, were with the doubtful exception
of one or two of the smallest grains, not at all rounded.  Nevertheless
some of them appeared a little worn, though not rounded.  Notwithstanding
these cases, if we consider the evidence above given, there can be little
doubt that the fragments, which serve as millstones in the gizzards of
worms, suffer, when of a not very hard texture, some amount of attrition;
and that the smaller particles in the earth, which is habitually
swallowed in such astonishingly large quantities by worms, are ground
together and are thus levigated.  If this be the case, the “terra
tenuissima,”—the “pâte excessivement fine,”—of which the castings largely
consist, is in part due to the mechanical action of the gizzard; {234}
and this fine matter, as we shall see in the next chapter, is that which
is chiefly washed away from the innumerable castings on every field
during each heavy shower of rain.  If the softer stones yield at all, the
harder ones will suffer some slight amount of wear and tear.

The trituration of small particles of stone in the gizzards of worms is
of more importance under a geological point of view than may at first
appear to be the case; for Mr. Sorby has clearly shown that the ordinary
means of disintegration, namely, running water and the waves of the sea,
act with less and less power on fragments of rock the smaller they are.
“Hence,” as he remarks, “even making no allowance for the extra buoying
up of very minute particles by a current of water, depending on surface
cohesion, the effects of wearing on the form of the grains must vary
directly as their diameter or thereabouts.  If so, a grain of 1/10 an
inch in diameter would be worn ten times as much as one of an inch in
diameter, and at least a hundred times as much as one of 1/100 an inch in
diameter.  Perhaps, then, we may conclude that a grain 1/10 of an inch in
diameter would be worn as much or more in drifting a mile as a grain
1/1000 of an inch in being drifted 100 miles.  On the same principle a
pebble one inch in diameter would be worn relatively more by being
drifted only a few hundred yards.” {236}  Nor should we forget, in
considering the power which worms exert in triturating particles of rock,
that there is good evidence that on each acre of land, which is
sufficiently damp and not too sandy, gravelly or rocky for worms to
inhabit, a weight of more than ten tons of earth annually passes through
their bodies and is brought to the surface.  The result for a country of
the size of Great Britain, within a period not very long in a geological
sense, such as a million years, cannot be insignificant; for the ten tons
of earth has to be multiplied first by the above number of years, and
then by the number of acres fully stocked with worms; and in England,
together with Scotland, the land which is cultivated and is well fitted
for these animals, has been estimated at above 32 million acres.  The
product is 320 million million tons of earth.



CHAPTER VI.
THE DENUDATION OF THE LAND—_continued_.


Denudation aided by recently ejected castings flowing down inclined
grass-covered surfaces—The amount of earth which annually flows
downwards—The effect of tropical rain on worm castings—The finest
particles of earth washed completely away from castings—The
disintegration of dried castings into pellets, and their rolling down
inclined surfaces—The formation of little ledges on hill-sides, in part
due to the accumulation of disintegrated castings—Castings blown to
leeward over level land—An attempt to estimate the amount thus blown—The
degradation of ancient encampments and tumuli—The preservation of the
crowns and furrows on land anciently ploughed—The formation and amount of
mould over the Chalk formation.

WE are now prepared to consider the more direct part which worms take in
the denudation of the land.  When reflecting on sub-aerial denudation, it
formerly appeared to me, as it has to others, that a nearly level or very
gently inclined surface, covered with turf, could suffer no loss during
even a long lapse of time.  It may, however, be urged that at long
intervals, debacles of rain or water-spouts would remove all the mould
from a very gentle slope; but when examining the steep, turf-covered
slopes in Glen Roy, I was struck with the fact how rarely any such event
could have happened since the Glacial period, as was plain from the
well-preserved state of the three successive “roads” or lake-margins.
But the difficulty in believing that earth in any appreciable quantity
can be removed from a gently inclined surface, covered with vegetation
and matted with roots, is removed through the agency of worms.  For the
many castings which are thrown up during rain, and those thrown up some
little time before heavy rain, flow for a short distance down an inclined
surface.  Moreover much of the finest levigated earth is washed
completely away from the castings.  During dry weather castings often
disintegrate into small rounded pellets, and these from their weight
often roll down any slope.  This is more especially apt to occur when
they are started by the wind, and probably when started by the touch of
an animal, however small.  We shall also see that a strong wind blows all
the castings, even on a level field, to leeward, whilst they are soft;
and in like manner the pellets when they are dry.  If the wind blows in
nearly the direction of an inclined surface, the flowing down of the
castings is much aided.

The observations on which these several statements are founded must now
be given in some detail.  Castings when first ejected are viscid and
soft; during rain, at which time worms apparently prefer to eject them,
they are still softer; so that I have sometimes thought that worms must
swallow much water at such times.  However this may be, rain, even when
not very heavy, if long continued, renders recently-ejected castings
semi-fluid; and on level ground they then spread out into thin, circular,
flat discs, exactly as would so much honey or very soft mortar, with all
traces of their vermiform structure lost.  This latter fact was sometimes
made evident, when a worm had subsequently bored through a flat circular
disc of this kind, and heaped up a fresh vermiform mass in the centre.
These flat subsided discs have been repeatedly seen by me after heavy
rain, in many places on land of all kinds.

_On the flowing of wet castings_, _and the rolling of dry disintegrated
castings down inclined surfaces_.—When castings are ejected on an
inclined surface during or shortly before heavy rain, they cannot fail to
flow a little down the slope.  Thus, on some steep slopes in Knole Park,
which were covered with coarse grass and had apparently existed in this
state from time immemorial, I found (Oct. 22, 1872) after several wet
days that almost all the many castings were considerably elongated in the
line of the slope; and that they now consisted of smooth, only slightly
conical masses.  Whenever the mouths of the burrows could be found from
which the earth had been ejected, there was more earth below than above
them.  After some heavy storms of rain (Jan. 25, 1872) two rather steeply
inclined fields near Down, which had formerly been ploughed and were now
rather sparsely clothed with poor grass, were visited, and many castings
extended down the slopes for a length of 5 inches, which was twice or
thrice the usual diameter of the castings thrown up on the level parts of
these same fields.  On some fine grassy slopes in Holwood Park, inclined
at angles between 8° and 11° 30' with the horizon, where the surface
apparently had never been disturbed by the hand of man, castings abounded
in extraordinary numbers: and a space 16 inches in length transversely to
the slope and 6 inches in the line of the slope, was completely coated,
between the blades of grass, with a uniform sheet of confluent and
subsided castings.  Here also in many places the castings had flowed down
the slope, and now formed smooth narrow patches of earth, 6, 7, and 7½
inches in length.  Some of these consisted of two castings, one above the
other, which had become so completely confluent that they could hardly be
distinguished.  On my lawn, clothed with very fine grass, most of the
castings are black, but some are yellowish from earth having been brought
up from a greater depth than usual, and the flowing-down of these yellow
castings after heavy rain, could be clearly seen where the slope was 5°;
and where it was less than 1° some evidence of their flowing down could
still be detected.  On another occasion, after rain which was never
heavy, but which lasted for 18 hours, all the castings on this same
gently inclined lawn had lost their vermiform structure; and they had
flowed, so that fully two-thirds of the ejected earth lay below the
mouths of the burrows.

These observations led me to make others with more care.  Eight castings
were found on my lawn, where the grass-blades are fine and close
together, and three others on a field with coarse grass.  The inclination
of the surface at the eleven places where these castings were collected
varied between 4° 30' and 17° 30'; the mean of the eleven inclinations
being 9° 26'.  The length of the castings in the direction of the slope
was first measured with as much accuracy as their irregularities would
permit.  It was found possible to make these measurements within about of
an inch, but one of the castings was too irregular to admit of
measurement.  The average length in the direction of the slope of the
remaining ten castings was 2.03 inches.  The castings were then divided
with a knife into two parts along a horizontal line passing through the
mouth of the burrow, which was discovered by slicing off the turf; and
all the ejected earth was separately collected, namely, the part above
the hole and the part below.  Afterwards these two parts were weighed.
In every case there was much more earth below than above; the mean weight
of that above being 103 grains, and of that below 205 grains; so that the
latter was very nearly double the former.  As on level ground castings
are commonly thrown up almost equally round the mouths of the burrows,
this difference in weight indicates the amount of ejected earth which had
flowed down the slope.  But very many more observations would be
requisite to arrive at any general result; for the nature of the
vegetation and other accidental circumstances, such as the heaviness of
the rain, the direction and force of the wind, &c., appear to be more
important in determining the quantity of the earth which flows down a
slope than its angle.  Thus with four castings on my lawn (included in
the above eleven) where the mean slope was 7° 19', the difference in the
amount of earth above and below the burrows was greater than with three
other castings on the same lawn where the mean slope was 12° 5'.

We may, however, take the above eleven cases, which are accurate as far
as they go, and calculate the weight of the ejected earth which annually
flows down a slope having a mean inclination of 9° 26'.  This was done by
my son George.  It has been shown that almost exactly two-thirds of the
ejected earth is found below the mouth of the burrow and one-third above
it.  Now if the two-thirds which is below the hole be divided into two
equal parts, the upper half of this two-thirds exactly counterbalances
the one-third which is above the hole, so that as far as regards the
one-third above and the upper half of the two-thirds below, there is no
flow of earth down the hill-side.  The earth constituting the lower half
of the two-thirds is, however, displaced through distances which are
different for every part of it, but which may be represented by the
distance between the middle point of the lower half of the two-thirds and
the hole.  So that the average distance of displacement is a half of the
whole length of the worm-casting.  Now the average length of ten out of
the above eleven castings was 2.03 inches, and half of this we may take
as being 1 inch.  It may therefore be concluded that one-third of the
whole earth brought to the surface was in these cases carried down the
slope through 1 inch. {244}

It was shown in the third chapter that on Leith Hill Common, dry earth
weighing at least 7.453 lbs. was brought up by worms to the surface on a
square yard in the course of a year.  If a square yard be drawn on a
hillside with two of its sides horizontal, then it is clear that only
1/36 part of the earth brought up on that square yard would be near
enough to its lower side to cross it, supposing the displacement of the
earth to be through one inch.  But it appears that only ? of the earth
brought up can be considered to flow downwards; hence ? of 1/36 or 1/108
of 7.453 lbs. will cross the lower side of our square yard in a year.
Now 1/108 of 7.453 lbs. is 1.1 oz.  Therefore 1.1 oz. of dry earth will
annually cross each linear yard running horizontally along a slope having
the above inclination; or very nearly 7 lbs. will annually cross a
horizontal line, 100 yards in length, on a hill-side having this
inclination.

A more accurate, though still very rough, calculation can be made of the
bulk of earth, which in its natural damp state annually flows down the
same slope over a yard-line drawn horizontally across it.  From the
several cases given in the third chapter, it is known that the castings
annually brought to the surface on a square yard, if uniformly spread out
would form a layer 0.2 of an inch in thickness: it therefore follows by a
calculation similar to the one already given, that ? of 0.2 × 36, or 2.4
cubic inches of damp earth will annually cross a horizontal line one yard
in length on a hillside with the above inclination.  This bulk of damp
castings was found to weigh 1.85 oz.  Therefore 11.56 lbs. of damp earth,
instead of 7 lbs. of dry earth as by the former calculation, would
annually cross a line 100 yards in length on our inclined surface.

In these calculations it has been assumed that the castings flow a short
distance downwards during the whole year, but this occurs only with those
ejected during or shortly before rain; so that the above results are thus
far exaggerated.  On the other hand, during rain much of the finest earth
is washed to a considerable distance from the castings, even where the
slope is an extremely gentle one, and is thus wholly lost as far as the
above calculations are concerned.  Castings ejected during dry weather
and which have set hard, lose in the same manner a considerable quantity
of fine earth.  Dried castings, moreover, are apt to disintegrate into
little pellets, which often roll or are blown down any inclined surface.
Therefore the above result, namely, that 24 cubic inches of earth
(weighing 1.85 oz. whilst damp) annually crosses a yard-line of the
specified kind, is probably not much if at all exaggerated.

This amount is small; but we should bear in mind how many branching
valleys intersect most countries, the whole length of which must be very
great; and that earth is steadily travelling down both turf-covered sides
of each valley.  For every 100 yards in length in a valley with sides
sloping as in the foregoing cases, 480 cubic inches of damp earth,
weighing above 23 pounds, will annually reach the bottom.  Here a thick
bed of alluvium will accumulate, ready to be washed away in the course of
centuries, as the stream in the middle meanders from side to side.

If it could be shown that worms generally excavate their burrows at right
angles to an inclined surface, and this would be their shortest course
for bringing up earth from beneath, then as the old burrows collapsed
from the weight of the superincumbent soil, the collapsing would
inevitably cause the whole bed of vegetable mould to sink or slide slowly
down the inclined surface.  But to ascertain the direction of many
burrows was found too difficult and troublesome.  A straight piece of
wire was, however, pushed into twenty-five burrows on several sloping
fields, and in eight cases the burrows were nearly at right angles to the
slope; whilst in the remaining cases they were indifferently directed at
various angles, either upwards or downwards with respect to the slope.

In countries where the rain is very heavy, as in the tropics, the
castings appear, as might have been expected, to be washed down in a
greater degree than in England.  Mr. Scott informs me that near Calcutta
the tall columnar castings (previously described), the diameter of which
is usually between 1 and 1½ inch, subside on a level surface, after heavy
rain, into almost circular, thin, flat discs, between 3 and 4 and
sometimes 5 inches in diameter.  Three fresh castings, which had been
ejected in the Botanic Gardens “on a slightly inclined, grass-covered,
artificial bank of loamy clay,” were carefully measured, and had a mean
height of 2.17, and a mean diameter of 1.43 inches; these after heavy
rain, formed elongated patches of earth, with a mean length in the
direction of the slope of 5.83 inches.  As the earth had spread very
little up the slope, a large part, judging from the original diameter of
these castings, must have flowed bodily downwards about 4 inches.
Moreover some of the finest earth of which they were composed must have
been washed completely away to a still greater distance.  In drier sites
near Calcutta, a species of worm ejects its castings, not in vermiform
masses, but in little pellets of varying sizes: these are very numerous
in some places, and Mr. Scott says that they “are washed away by every
shower.”

I was led to believe that a considerable quantity of fine earth is washed
quite away from castings during rain, from the surfaces of old ones being
often studded with coarse particles.  Accordingly a little fine
precipitated chalk, moistened with saliva or gum-water, so as to be
slightly viscid and of the same consistence as a fresh casting, was
placed on the summits of several castings and gently mixed with them.
These castings were then watered through a very fine rose, the drops from
which were closer together than those of rain, but not nearly so large as
those in a thunderstorm; nor did they strike the ground with nearly so
much force as drops during heavy rain.  A casting thus treated subsided
with surprising slowness, owing as I suppose to its viscidity.  It did
not flow bodily down the grass-covered surface of the lawn, which was
here inclined at an angle of 16° 20'; nevertheless many particles of the
chalk were found three inches below the casting.  The experiment was
repeated on three other castings on different parts of the lawn, which
sloped at 2° 30', 3° and 6°; and particles of chalk could be seen between
4 and 5 inches below the casting; and after the surface had become dry,
particles were found in two cases at a distance of 5 and 6 inches.
Several other castings with precipitated chalk placed on their summits
were left to the natural action of the rain.  In one case, after rain
which was not heavy, the casting was longitudinally streaked with white.
In two other cases the surface of the ground was rendered somewhat white
for a distance of one inch from the casting; and some soil collected at a
distance of 2½ inches, where the slope was 7°, effervesced slightly when
placed in acid.  After one or two weeks, the chalk was wholly or almost
wholly washed away from all the castings on which it had been placed, and
these had recovered their natural colour.

It may be here remarked that after very heavy rain shallow pools may be
seen on level or nearly level fields, where the soil is not very porous,
and the water in them is often slightly muddy; when such little pools
have dried, the leaves and blades of grass at their bottoms are generally
coated with a thin layer of mud.  This mud I believe is derived in large
part from recently ejected castings.

Dr. King informs me that the majority of the before described gigantic
castings, which he found on a fully exposed, bare, gravelly knoll on the
Nilgiri Mountains in India, had been more or less weathered by the
previous north-east monsoon; and most of them presented a subsided
appearance.  The worms here eject their castings only during the rainy
season; and at the time of Dr. King’s visit no rain had fallen for 110
days.  He carefully examined the ground between the place where these
huge castings lay, and a little watercourse at the base of the knoll, and
nowhere was there any accumulation of fine earth, such as would
necessarily have been left by the disintegration of the castings if they
had not been wholly removed.  He therefore has no hesitation in asserting
that the whole of these huge castings are annually washed during the two
monsoons (when about 100 inches of rain fall) into the little
water-course, and thence into the plains lying below at a depth of 3000
or 4000 feet.

Castings ejected before or during dry weather become hard, sometimes
surprisingly hard, from the particles of earth having been cemented
together by the intestinal secretions.  Frost seems to be less effective
in their disintegration than might have been expected.  Nevertheless they
readily disintegrate into small pellets, after being alternately
moistened with rain and again dried.  Those which have flowed during rain
down a slope, disintegrate in the same manner.  Such pellets often roll a
little down any sloping surface; their descent being sometimes much aided
by the wind.  The whole bottom of a broad dry ditch in my grounds, where
there were very few fresh castings, was completely covered with these
pellets or disintegrated castings, which had rolled down the steep sides,
inclined at an angle of 27°.

Near Nice, in places where the great cylindrical castings, previously
described, abound, the soil consists of very fine arenaceo-calcareous
loam; and Dr. King informs me that these castings are extremely liable to
crumble during dry weather into small fragments, which are soon acted on
by rain, and then sink down so as to be no longer distinguishable from
the surrounding soil.  He sent me a mass of such disintegrated castings,
collected on the top of a bank, where none could have rolled down from
above.  They must have been ejected within the previous five or six
months, but they now consisted of more or less rounded fragments of all
sizes, from ¾ of an inch in diameter to minute grains and mere dust.  Dr.
King witnessed the crumbling process whilst drying some perfect castings,
which he afterwards sent me.  Mr. Scott also remarks on the crumbling of
the castings near Calcutta and on the mountains of Sikkim during the hot
and dry season.

When the castings near Nice had been ejected on an inclined surface, the
disintegrated fragments rolled downwards, without losing their
distinctive shape; and in some places could “be collected in basketfuls.”
Dr. King observed a striking instance of this fact on the Corniche road,
where a drain, about 2½ feet wide and 9 inches deep, had been made to
catch the surface drainage from the adjoining hill-side.  The bottom of
this drain was covered for a distance of several hundred yards, to a
depth of from 1½ to 3 inches, by a layer of broken castings, still
retaining their characteristic shape.  Nearly all these innumerable
fragments had rolled down from above, for extremely few castings had been
ejected in the drain itself.  The hill-side was steep, but varied much in
inclination, which Dr. King estimated at from 30° to 60° with the
horizon.  He climbed up the slope, and “found every here and there little
embankments, formed by fragments of the castings that had been arrested
in their downward progress by irregularities of the surface, by stones,
twigs, &c.  One little group of plants of _Anemone hortensis_ had acted
in this manner, and quite a small bank of soil had collected round it.
Much of this soil had crumbled down, but a great deal of it still
retained the form of castings.”  Dr. King dug up this plant, and was
struck with the thickness of the soil which must have recently
accumulated over the crown of the rhizoma, as shown by the length of the
bleached petioles, in comparison with those of other plants of the same
kind, where there had been no such accumulation.  The earth thus
accumulated had no doubt been secured (as I have everywhere seen) by the
smaller roots of the plants.  After describing this and other analogous
cases, Dr. King concludes: “I can have no doubt that worms help greatly
in the process of denudation.”

_Ledges of earth on steep hill-sides_.—Little horizontal ledges, one
above another, have been observed on steep grassy slopes in many parts of
the world.  The formation has been attributed to animals travelling
repeatedly along the slope in the same horizontal lines while grazing,
and that they do thus move and use the ledges is certain; but Professor
Henslow (a most careful observer) told Sir J. Hooker that he was
convinced that this was not the sole cause of their formation.  Sir J.
Hooker saw such ledges on the Himalayan and Atlas ranges, where there
were no domesticated animals and not many wild ones; but these latter
would, it is probable, use the ledges at night while grazing like our
domesticated animals.  A friend observed for me the ledges on the Alps of
Switzerland, and states that they ran at 3 or 4 ft. one above the other,
and were about a foot in breadth.  They had been deeply pitted by the
feet of grazing cows.  Similar ledges were observed by the same friend on
our Chalk downs, and on an old talus of chalk-fragments (thrown out of a
quarry) which had become clothed with turf.

My son Francis examined a Chalk escarpment near Lewes; and here on a part
which was very steep, sloping at 40° with the horizon, about 30 flat
ledges extended horizontally for more than 100 yards, at an average
distance of about 20 inches, one beneath the other.  They were from 9 to
10 inches in breadth.  When viewed from a distance they presented a
striking appearance, owing to their parallelism; but when examined
closely, they were seen to be somewhat sinuous, and one often ran into
another, giving the appearance of the ledge having forked into two.  They
are formed of light-coloured earth, which on the outside, where thickest,
was in one case 9 inches, and in another case between 6 and 7 inches in
thickness.  Above the ledges, the thickness of the earth over the chalk
was in the former case 4 and in the latter only 3 inches.  The grass grew
more vigorously on the outer edges of the ledges than on any other part
of the slope, and here formed a tufted fringe.  Their middle part was
bare, but whether this had been caused by the trampling of sheep, which
sometimes frequent the ledges, my son could not ascertain.  Nor could he
feel sure how much of the earth on the middle and bare parts, consisted
of disintegrated worm-castings which had rolled down from above; but he
felt convinced that some had thus originated; and it was manifest that
the ledges with their grass-fringed edges would arrest any small object
rolling down from above.

At one end or side of the bank bearing these ledges, the surface
consisted in parts of bare chalk, and here the ledges were very
irregular.  At the other end of the bank, the slope suddenly became less
steep, and here the ledges ceased rather abruptly; but little embankments
only a foot or two in length were still present.  The slope became
steeper lower down the hill, and the regular ledges then reappeared.
Another of my sons observed, on the inland side of Beachy Head, where the
surface sloped at about 25°, many short little embankments like those
just mentioned.  They extended horizontally and were from a few inches to
two or three feet in length.  They supported tufts of grass growing
vigorously.  The average thickness of the mould of which they were
formed, taken from nine measurements, was 4.5 inches; while that of the
mould above and beneath them was on an average only 3.2 inches, and on
each side, on the same level, 3.1 inches.  On the upper parts of the
slope, these embankments showed no signs of having been trampled on by
sheep, but in the lower parts such signs were fairly plain.  No long
continuous ledges had here been formed.

If the little embankments above the Corniche road, which Dr. King saw in
the act of formation by the accumulation of disintegrated and rolled
worm-castings, were to become confluent along horizontal lines, ledges
would be formed.  Each embankment would tend to extend laterally by the
lateral extension of the arrested castings; and animals grazing on a
steep slope would almost certainly make use of every prominence at nearly
the same level, and would indent the turf between them; and such
intermediate indentations would again arrest the castings.  An irregular
ledge when once formed would also tend to become more regular and
horizontal by some of the castings rolling laterally from the higher to
the lower parts, which would thus be raised.  Any projection beneath a
ledge would not afterwards receive disintegrated matter from above, and
would tend to be obliterated by rain and other atmospheric agencies.
There is some analogy between the formation, as here supposed, of these
ledges, and that of the ripples of wind-drifted sand as described by
Lyell. {259}

The steep, grass-covered sides of a mountainous valley in Westmoreland,
called Grisedale, was marked in many places with innumerable lines of
miniature cliffs, with almost horizontal, little ledges at their bases.
Their formation was in no way connected with the action of worms, for
castings could not anywhere be seen (and their absence is an inexplicable
fact), although the turf lay in many places over a considerable thickness
of boulder-clay and moraine rubbish.  Nor, as far as I could judge, was
the formation of these little cliffs at all closely connected with the
trampling of cows or sheep.  It appeared as if the whole superficial,
somewhat argillaceous earth, while partially held together by the roots
of the grasses, had slided a little way down the mountain sides; and in
thus sliding, had yielded and cracked in horizontal lines, transversely
to the slope.

_Castings blown to leeward by the wind_.—We have seen that moist castings
flow, and that disintegrated castings roll down any inclined surface; and
we shall now see that castings, recently ejected on level grass-covered
surfaces, are blown during gales of wind accompanied by rain to leeward.
This has been observed by me many times on many fields during several
successive years.  After such gales, the castings present a gently
inclined and smooth, or sometimes furrowed, surface to windward, while
they are steeply inclined or precipitous to leeward, so that they
resemble on a miniature scale glacier-ground hillocks of rock.  They are
often cavernous on the leeward side, from the upper part having curled
over the lower part.  During one unusually heavy south-west gale with
torrents of rain, many castings were wholly blown to leeward, so that the
mouths of the burrows were left naked and exposed on the windward side.
Recent castings naturally flow down an inclined surface, but on a grassy
field, which sloped between 10° and 15°, several were found after a heavy
gale blown up the slope.  This likewise occurred on another occasion on a
part of my lawn where the slope was somewhat less.  On a third occasion,
the castings on the steep, grass-covered sides of a valley, down which a
gale had blown, were directed obliquely instead of straight down the
slope; and this was obviously due to the combined action of the wind and
gravity.  Four castings on my lawn, where the downward inclination was 0°
45', 1°, 3° and 3° 30' (mean 2° 45') towards the north-east, after a
heavy south-west gale with rain, were divided across the mouths of the
burrows and weighed in the manner formerly described.  The mean weight of
the earth below the mouths of burrows and to leeward, was to that above
the mouths and on the windward side as 2¾ to 1; whereas we have seen that
with several castings which had flowed down slopes having a mean
inclination of 9° 26', and with three castings where the inclination was
above 12°; the proportional weight of the earth below to that above the
burrows was as only 2 to 1.  These several cases show how efficiently
gales of wind accompanied by rain act in displacing recently ejected
castings.  We may therefore conclude that even a moderately strong wind
will produce some slight effect on them.

Dry and indurated castings, after their disintegration into small
fragments or pellets, are sometimes, probably often, blown by a strong
wind to leeward.  This was observed on four occasions, but I did not
sufficiently attend to this point.  One old casting on a gently sloping
bank was blown quite away by a strong south-west wind.  Dr. King believes
that the wind removes the greater part of the old crumbling castings near
Nice.  Several old castings on my lawn were marked with pins and
protected from any disturbance.  They were examined after an interval of
10 weeks, during which time the weather had been alternately dry and
rainy.  Some, which were of a yellowish colour had been washed almost
completely away, as could be seen by the colour of the surrounding
ground.  Others had completely disappeared, and these no doubt had been
blown away.  Lastly, others still remained and would long remain, as
blades of grass had grown through them.  On poor pasture-land, which has
never been rolled and has not been much trampled on by animals, the whole
surface is sometimes dotted with little pimples, through and on which
grass grows; and these pimples consist of old worm-castings.

In all the many observed cases of soft castings blown to leeward, this
had been effected by strong winds accompanied by rain.  As such winds in
England generally blow from the south and south-west, earth must on the
whole tend to travel over our fields in a north and north-east direction.
This fact is interesting, because it might be thought that none could be
removed from a level, grass-covered surface by any means.  In thick and
level woods, protected from the wind, castings will never be removed as
long as the wood lasts; and mould will here tend to accumulate to the
depth at which worms can work.  I tried to procure evidence as to how
much mould is blown, whilst in the state of castings, by our wet southern
gales to the north-east, over open and flat land, by looking to the level
of the surface on opposite sides of old trees and hedge-rows; but I
failed owing to the unequal growth of the roots of trees and to most
pasture-land having been formerly ploughed.

On an open plain near Stonehenge, there exist shallow circular trenches,
with a low embankment outside, surrounding level spaces 50 yards in
diameter.  These rings appear very ancient, and are believed to be
contemporaneous with the Druidical stones.  Castings ejected within these
circular spaces, if blown to the north-east by south-west winds would
form a layer of mould within the trench, thicker on the north-eastern
than on any other side.  But the site was not favourable for the action
of worms, for the mould over the surrounding Chalk formation with flints,
was only 3.37 inches in thickness, from a mean of six observations made
at a distance of 10 yards outside the embankment.  The thickness of the
mould within two of the circular trenches was measured every 5 yards all
round, on the inner sides near the bottom.  My son Horace protracted
these measurements on paper; and though the curved line representing the
thickness of the mould was extremely irregular, yet in both diagrams it
could be seen to be thicker on the north-eastern side than elsewhere.
When a mean of all the measurements in both the trenches was laid down
and the line smoothed, it was obvious that the mould was thickest in the
quarter of the circle between north-west and north-east; and thinnest in
the quarter between south-east and south-west, especially at this latter
point.  Besides the foregoing measurements, six others were taken near
together in one of the circular trenches, on the north-east side; and the
mould here had a mean thickness of 2.29 inches; while the mean of six
other measurements on the south-west side was only 1.46 inches.  These
observations indicate that the castings had been blown by the south-west
winds from the circular enclosed space into the trench on the north-east
side; but many more measurements in other analogous cases would be
requisite for a trustworthy result.

The amount of fine earth brought to the surface under the form of
castings, and afterwards transported by the winds accompanied by rain, or
that which flows and rolls down an inclined surface, no doubt is small in
the course of a few scores of years; for otherwise all the inequalities
in our pasture fields would be smoothed within a much shorter period than
appears to be the case.  But the amount which is thus transported in the
course of thousands of years cannot fail to be considerable and deserves
attention.  É. de Beaumont looks at the vegetable mould which everywhere
covers the land as a fixed line, from which the amount of denudation may
be measured. {265}  He ignores the continued formation of fresh mould by
the disintegration of the underlying rocks and fragments of rock; and it
is curious to find how much more philosophical were the views maintained
long ago, by Playfair, who, in 1802, wrote, “In the permanence of a coat
of vegetable mould on the surface of the earth, we have a demonstrative
proof of the continued destruction of the rocks.” {266}

_Ancient encampments and tumuli_.—É. de Beaumont adduces the present
state of many ancient encampments and tumuli and of old ploughed fields,
as evidence that the surface of the land undergoes hardly any
degradation.  But it does not appear that he ever examined the thickness
of the mould over different parts of such old remains.  He relies chiefly
on indirect, but apparently trustworthy, evidence that the slopes of the
old embankments are the same as they originally were; and it is obvious
that he could know nothing about their original heights.  In Knole Park a
mound had been thrown up behind the rifle-targets, which appeared to have
been formed of earth originally supported by square blocks of turf.  The
sides sloped, as nearly as I could estimate them, at an angle of 45° or
50° with the horizon, and they were covered, especially on the northern
side, with long coarse grass, beneath which many worm-castings were
found.  These had flowed bodily downwards, and others had rolled down as
pellets.  Hence it is certain that as long as a mound of this kind is
tenanted by worms, its height will be continually lowered.  The fine
earth which flows or rolls down the sides of such a mound accumulates at
its base in the form of a talus.  A bed, even a very thin bed, of fine
earth is eminently favourable for worms; so that a greater number of
castings would tend to be ejected on a talus thus formed than elsewhere;
and these would be partially washed away by every heavy shower and be
spread over the adjoining level ground.  The final result would be the
lowering of the whole mound, whilst the inclination of the sides would
not be greatly lessened.  The same result would assuredly follow with
ancient embankments and tumuli; except where they had been formed of
gravel or of nearly pure sand, as such matter is unfavourable for worms.
Many old fortifications and tumuli are believed to be at least 2000 years
old; and we should bear in mind that in many places about one inch of
mould is brought to the surface in 5 years or two inches in 10 years.
Therefore in so long a period as 2000 years, a large amount of earth will
have been repeatedly brought to the surface on most old embankments and
tumuli, especially on the talus round their bases, and much of this earth
will have been washed completely away.  We may therefore conclude that
all ancient mounds, when not formed of materials unfavourable to worms,
will have been somewhat lowered in the course of centuries, although
their inclinations may not have been greatly changed.

_Fields formerly ploughed_.—From a very remote period and in many
countries, land has been ploughed, so that convex beds, called crowns or
ridges, usually about 8 feet across and separated by furrows, have been
thrown up.  The furrows are directed so as to carry off the surface
water.  In my attempts to ascertain how long a time these crowns and
furrows last, when ploughed land has been converted into pasture,
obstacles of many kinds were encountered.  It is rarely known when a
field was last ploughed; and some fields which were thought to have been
in pasture from time immemorial were afterwards discovered to have been
ploughed only 50 or 60 years before.  During the early part of the
present century, when the price of corn was very high, land of all kinds
seems to have been ploughed in Britain.  There is, however, no reason to
doubt that in many cases the old crowns and furrows have been preserved
from a very ancient period. {269}  That they should have been preserved
for very unequal lengths of time would naturally follow from the crowns,
when first thrown up, having differed much in height in different
districts, as is now the case with recently ploughed land.

In old pasture fields, the mould, wherever measurements were made, was
found to be from ½ to 2 inches thicker in the furrows than on the crowns;
but this would naturally follow from the finer earth having been washed
from the crowns into the furrows before the land was well clothed with
turf; and it is impossible to tell what part worms may have played in the
work.  Nevertheless from what we have seen, castings would certainly tend
to flow and to be washed during heavy rain from the crowns into the
furrows.  But as soon as a bed of fine earth had by any means been
accumulated in the furrows, it would be more favourable for worms than
the other parts, and a greater number of castings would be thrown up here
than elsewhere; and as the furrows on sloping land are usually directed
so as to carry off the surface water, some of the finest earth would be
washed from the castings which had been here ejected and be carried
completely away.  The result would be that the furrows would be filled up
very slowly, while the crowns would be lowered perhaps still more slowly
by the flowing and rolling of the castings down their gentle inclinations
into the furrows.

Nevertheless it might be expected that old furrows, especially those on a
sloping surface, would in the course of time be filled up and disappear.
Some careful observers, however, who examined fields for me in
Gloucestershire and Staffordshire could not detect any difference in the
state of the furrows in the upper and lower parts of sloping fields,
supposed to have been long in pasture; and they came to the conclusion
that the crowns and furrows would last for an almost endless number of
centuries.  On the other hand the process of obliteration seems to have
commenced in some places.  Thus in a grass field in North Wales, known to
have been ploughed about 65 years ago, which sloped at an angle of 15° to
the north-east, the depth of the furrows (only 7 feet apart) was
carefully measured, and was found to be about 4½ inches in the upper part
of the slope, and only 1 inch near the base, where they could be traced
with difficulty.  On another field sloping at about the same angle to the
south-west, the furrows were scarcely perceptible in the lower part;
although these same furrows when followed on to some adjoining level
ground were from 2½ to 3½ inches in depth.  A third and closely similar
case was observed.  In a fourth case, the mould in a furrow in the upper
part of a sloping field was 2½ inches, and in the lower part 4½ inches in
thickness.

On the Chalk Downs at about a mile distance from Stonehenge, my son
William examined a grass-covered, furrowed surface, sloping at from 8° to
10 °, which an old shepherd said had not been ploughed within the memory
of man.  The depth of one furrow was measured at 16 points in a length of
68 paces, and was found to be deeper where the slope was greatest and
where less earth would naturally tend to accumulate, and at the base it
almost disappeared.  The thickness of the mould in this furrow in the
upper part was 2½ inches, which increased to 5 inches, a little above the
steepest part of the slope; and at the base, in the middle of the narrow
valley, at a point which the furrow if continued would have struck, it
amounted to 7 inches.  On the opposite side of the valley, there were
very faint, almost obliterated, traces of furrows.  Another analogous but
not so decided a case was observed at a few miles’ distance from
Stonehenge.  On the whole it appears that the crowns and furrows on land
formerly ploughed, but now covered with grass, tend slowly to disappear
when the surface is inclined; and this is probably in large part due to
the action of worms; but that the crowns and furrows last for a very long
time when the surface is nearly level.

_Formation and amount of mould over the Chalk Formation_.—Worm-castings
are often ejected in extraordinary numbers on steep, grass-covered
slopes, where the Chalk comes close to the surface, as my son William
observed near Winchester and elsewhere.  If such castings are largely
washed away during heavy rains, it is difficult to understand at first
how any mould can still remain on our Downs, as there does not appear any
evident means for supplying the loss.  There is, moreover, another cause
of loss, namely, in the percolation of the finer particles of earth into
the fissures in the chalk and into the chalk itself.  These
considerations led me to doubt for a time whether I had not exaggerated
the amount of fine earth which flows or rolls down grass-covered slopes
under the form of castings; and I sought for additional information.  In
some places, the castings on Chalk Downs consist largely of calcareous
matter, and here the supply is of course unlimited.  But in other places,
for instance on a part of Teg Down near Winchester, the castings were all
black and did not effervesce with acids.  The mould over the chalk was
here only from 3 to 4 inches in thickness.  So again on the plain near
Stonehenge, the mould, apparently free from calcareous matter, averaged
rather less than 3½ inches in thickness.  Why worms should penetrate and
bring up chalk in some places and not in others I do not know.

In many districts where the land is nearly level, a bed several feet in
thickness of red clay full of unworn flints overlies the Upper Chalk.
This overlying matter, the surface of which has been converted into
mould, consists of the undissolved residue from the chalk.  It may be
well here to recall the case of the fragments of chalk buried beneath
worm-castings on one of my fields, the angles of which were so completely
rounded in the course of 29 years that the fragments now resembled
water-worn pebbles.  This must have been effected by the carbonic acid in
the rain and in the ground, by the humus-acids, and by the corroding
power of living roots.  Why a thick mass of residue has not been left on
the Chalk, wherever the land is nearly level, may perhaps be accounted
for by the percolation of the fine particles into the fissures, which are
often present in the chalk and are either open or are filled up with
impure chalk, or into the solid chalk itself.  That such percolation
occurs can hardly be doubted.  My son collected some powdered and
fragmentary chalk beneath the turf near Winchester; the former was found
by Colonel Parsons, R. E., to contain 10 per cent., and the fragments 8
per cent. of earthy matter.  On the flanks of the escarpment near Abinger
in Surrey, some chalk close beneath a layer of flints, 2 inches in
thickness and covered by 8 inches of mould, yielded a residue of 3.7 per
cent. of earthy matter.  On the other hand the Upper Chalk properly
contains, as I was informed by the late David Forbes who had made many
analyses, only from 1 to 2 per cent. of earthy matter; and two samples
from pits near my house contained 1.3 and 0.6 per cent.  I mention these
latter cases because, from the thickness of the overlying bed of red clay
with flints, I had imagined that the underlying chalk might here be less
pure than elsewhere.  The cause of the residue accumulating more in some
places than in others, may be attributed to a layer of argillaceous
matter having been left at an early period on the chalk, and this would
check the subsequent percolation of earthy matter into it.

From the facts now given we may conclude that castings ejected on our
Chalk Downs suffer some loss by the percolation of their finer matter
into the chalk.  But such impure superficial chalk, when dissolved, would
leave a larger supply of earthy matter to be added to the mould than in
the case of pure chalk.  Besides the loss caused by percolation, some
fine earth is certainly washed down the sloping grass-covered surfaces of
our Downs.  The washing-down process, however, will be checked in the
course of time; for although I do not know how thin a layer of mould
suffices to support worms, yet a limit must at last be reached; and then
their castings would cease to be ejected or would become scanty.

The following cases show that a considerable quantity of fine earth is
washed down.  The thickness of the mould was measured at points 12 yards
apart across a small valley in the Chalk near Winchester.  The sides
sloped gently at first; then became inclined at about 20°; then more
gently to near the bottom, which transversely was almost level and about
50 yards across.  In the bottom, the mean thickness of the mould from
five measurements was 8.3 inches; whilst on the sides of the valley,
where the inclination varied between 14° and 20°, its mean thickness was
rather less than 3.5 inches.  As the turf-covered bottom of the valley
sloped at an angle of only between 2° and 3°, it is probable that most of
the 8.3-inch layer of mould had been washed down from the flanks of the
valley, and not from the upper part.  But as a shepherd said that he had
seen water flowing in this valley after the sudden thawing of snow, it is
possible that some earth may have been brought down from the upper part;
or, on the other hand, that some may have been carried further down the
valley.  Closely similar results, with respect to the thickness of the
mould, were obtained in a neighbouring valley.

St. Catherine’s Hill, near Winchester, is 327 feet in height, and
consists of a steep cone of chalk about ¼ of a mile in diameter.  The
upper part was converted by the Romans, or, as some think, by the ancient
Britons, into an encampment, by the excavation of a deep and broad ditch
all round it.  Most of the chalk removed during the work was thrown
upwards, by which a projecting bank was formed; and this effectually
prevents worm-castings (which are numerous in parts), stones, and other
objects from being washed or rolled into the ditch.  The mould on the
upper and fortified part of the hill was found to be in most places only
from 2½ to 3½ inches in thickness; whereas it had accumulated at the foot
of the embankment above the ditch to a thickness in most places of from 8
to 9½ inches.  On the embankment itself the mould was only 1 to 1½ inch
in thickness; and within the ditch at the bottom it varied from 2½ to 3½,
but was in one spot 6 inches in thickness.  On the north-west side of the
hill, either no embankment had ever been thrown up above the ditch, or it
had subsequently been removed; so that here there was nothing to prevent
worm-castings, earth and stones being washed into the ditch, at the
bottom of which the mould formed a layer from 11 to 22 inches in
thickness.  It should however be stated that here and on other parts of
the slope, the bed of mould often contained fragments of chalk and flint
which had obviously rolled down at different times from above.  The
interstices in the underlying fragmentary chalk were also filled up with
mould.

My son examined the surface of this hill to its base in a south-west
direction.  Beneath the great ditch, where the slope was about 24°, the
mould was very thin, namely, from 1½ to 2½ inches; whilst near the base,
where the slope was only 3° to 4°, it increased to between 8 and 9 inches
in thickness.  We may therefore conclude that on this artificially
modified hill, as well as in the natural valleys of the neighbouring
Chalk Downs, some fine earth, probably derived in large part from
worm-castings, is washed down, and accumulates in the lower parts,
notwithstanding the percolation of an unknown quantity into the
underlying chalk; a supply of fresh earthy matter being afforded by the
dissolution of the chalk through atmospheric and other agencies.




CHAPTER VII.
CONCLUSION.


Summary of the part which worms have played in the history of the
world—Their aid in the disintegration of rocks—In the denudation of the
land—In the preservation of ancient remains—In the preparation of the
soil for the growth of plants—Mental powers of worms—Conclusion.

WORMS have played a more important part in the history of the world than
most persons would at first suppose.  In almost all humid countries they
are extraordinarily numerous, and for their size possess great muscular
power.  In many parts of England a weight of more than ten tons (10,516
kilogrammes) of dry earth annually passes through their bodies and is
brought to the surface on each acre of land; so that the whole
superficial bed of vegetable mould passes through their bodies in the
course of every few years.  From the collapsing of the old burrows the
mould is in constant though slow movement, and the particles composing it
are thus rubbed together.  By these means fresh surfaces are continually
exposed to the action of the carbonic acid in the soil, and of the
humus-acids which appear to be still more efficient in the decomposition
of rocks.  The generation of the humus-acids is probably hastened during
the digestion of the many half-decayed leaves which worms consume.  Thus
the particles of earth, forming the superficial mould, are subjected to
conditions eminently favourable for their decomposition and
disintegration.  Moreover, the particles of the softer rocks suffer some
amount of mechanical trituration in the muscular gizzards of worms, in
which small stones serve as mill-stones.

The finely levigated castings, when brought to the surface in a moist
condition, flow during rainy weather down any moderate slope; and the
smaller particles are washed far down even a gently inclined surface.
Castings when dry often crumble into small pellets and these are apt to
roll down any sloping surface.  Where the land is quite level and is
covered with herbage, and where the climate is humid so that much dust
cannot be blown away, it appears at first sight impossible that there
should be any appreciable amount of sub-aerial denudation; but
worm-castings are blown, especially whilst moist and viscid, in one
uniform direction by the prevalent winds which are accompanied by rain.
By these several means the superficial mould is prevented from
accumulating to a great thickness; and a thick bed of mould checks in
many ways the disintegration of the underlying rocks and fragments of
rock.

The removal of worm-castings by the above means leads to results which
are far from insignificant.  It has been shown that a layer of earth, 0.2
of an inch in thickness, is in many places annually brought to the
surface; and if a small part of this amount flows, or rolls, or is
washed, even for a short distance, down every inclined surface, or is
repeatedly blown in one direction, a great effect will be produced in the
course of ages.  It was found by measurements and calculations that on a
surface with a mean inclination of 9° 26', 2.4 cubic inches of earth
which had been ejected by worms crossed, in the course of a year, a
horizontal line one yard in length; so that 240 cubic inches would cross
a line 100 yards in length.  This latter amount in a damp state would
weigh 11½ pounds.  Thus a considerable weight of earth is continually
moving down each side of every valley, and will in time reach its bed.
Finally this earth will be transported by the streams flowing in the
valleys into the ocean, the great receptacle for all matter denuded from
the land.  It is known from the amount of sediment annually delivered
into the sea by the Mississippi, that its enormous drainage-area must on
an average be lowered .00263 of an inch each year; and this would suffice
in four and half million years to lower the whole drainage-area to the
level of the sea-shore.  So that, if a small fraction of the layer of
fine earth, 0.2 of an inch in thickness, which is annually brought to the
surface by worms, is carried away, a great result cannot fail to be
produced within a period which no geologist considers extremely long.

                                * * * * *

Archæologists ought to be grateful to worms, as they protect and preserve
for an indefinitely long period every object, not liable to decay, which
is dropped on the surface of the land, by burying it beneath their
castings.  Thus, also, many elegant and curious tesselated pavements and
other ancient remains have been preserved; though no doubt the worms have
in these cases been largely aided by earth washed and blown from the
adjoining land, especially when cultivated.  The old tesselated pavements
have, however, often suffered by having subsided unequally from being
unequally undermined by the worms.  Even old massive walls may be
undermined and subside; and no building is in this respect safe, unless
the foundations lie 6 or 7 feet beneath the surface, at a depth at which
worms cannot work.  It is probable that many monoliths and some old walls
have fallen down from having been undermined by worms.

                                * * * * *

Worms prepare the ground {284} in an excellent manner for the growth of
fibrous-rooted plants and for seedlings of all kinds.  They periodically
expose the mould to the air, and sift it so that no stones larger than
the particles which they can swallow are left in it.  They mingle the
whole intimately together, like a gardener who prepares fine soil for his
choicest plants.  In this state it is well fitted to retain moisture and
to absorb all soluble substances, as well as for the process of
nitrification.  The bones of dead animals, the harder parts of insects,
the shells of land-molluscs, leaves, twigs, &c., are before long all
buried beneath the accumulated castings of worms, and are thus brought in
a more or less decayed state within reach of the roots of plants.  Worms
likewise drag an infinite number of dead leaves and other parts of plants
into their burrows, partly for the sake of plugging them up and partly as
food.

The leaves which are dragged into the burrows as food, after being torn
into the finest shreds, partially digested, and saturated with the
intestinal and urinary secretions, are commingled with much earth.  This
earth forms the dark coloured, rich humus which almost everywhere covers
the surface of the land with a fairly well-defined layer or mantle.
Hensen {285} placed two worms in a vessel 18 inches in diameter, which
was filled with sand, on which fallen leaves were strewed; and these were
soon dragged into their burrows to a depth of 3 inches.  After about 6
weeks an almost uniform layer of sand, a centimeter (0.4 inch) in
thickness, was converted into humus by having passed through the
alimentary canals of these two worms.  It is believed by some persons
that worm-burrows, which often penetrate the ground almost
perpendicularly to a depth of 5 or 6 feet, materially aid in its
drainage; notwithstanding that the viscid castings piled over the mouths
of the burrows prevent or check the rain-water directly entering them.
They allow the air to penetrate deeply into the ground.  They also
greatly facilitate the downward passage of roots of moderate size; and
these will be nourished by the humus with which the burrows are lined.
Many seeds owe their germination to having been covered by castings; and
others buried to a considerable depth beneath accumulated castings lie
dormant, until at some future time they are accidentally uncovered and
germinate.

Worms are poorly provided with sense-organs, for they cannot be said to
see, although they can just distinguish between light and darkness; they
are completely deaf, and have only a feeble power of smell; the sense of
touch alone is well developed.  They can therefore learn but little about
the outside world, and it is surprising that they should exhibit some
skill in lining their burrows with their castings and with leaves, and in
the case of some species in piling up their castings into tower-like
constructions.  But it is far more surprising that they should apparently
exhibit some degrees of intelligence instead of a mere blind instinctive
impulse, in their manner of plugging up the mouths of their burrows.
They act in nearly the same manner as would a man, who had to close a
cylindrical tube with different kinds of leaves, petioles, triangles of
paper, &c., for they commonly seize such objects by their pointed ends.
But with thin objects a certain number are drawn in by their broader
ends.  They do not act in the same unvarying manner in all cases, as do
most of the lower animals; for instance, they do not drag in leaves by
their foot-stalks, unless the basal part of the blade is as narrow as the
apex, or narrower than it.

                                * * * * *

When we behold a wide, turf-covered expanse, we should remember that its
smoothness, on which so much of its beauty depends, is mainly due to all
the inequalities having been slowly levelled by worms.  It is a
marvellous reflection that the whole of the superficial mould over any
such expanse has passed, and will again pass, every few years through the
bodies of worms.  The plough is one of the most ancient and most valuable
of man’s inventions; but long before he existed the land was in fact
regularly ploughed, and still continues to be thus ploughed by
earth-worms.  It may be doubted whether there are many other animals
which have played so important a part in the history of the world, as
have these lowly organized creatures.  Some other animals, however, still
more lowly organized, namely corals, have done far more conspicuous work
in having constructed innumerable reefs and islands in the great oceans;
but these are almost confined to the tropical zones.




FOOTNOTES.


{2}  ‘Leçons de Géologie Pratique,’ tom. i. 1845, p. 140.

{3}  ‘Transactions Geolog. Soc.’ vol. v. p. 505.  Read November 1, 1837.

{4a}  ‘Histoire des progrès de la Géologie,’ tom. i. 1847, p. 224.

{4b}  ‘Zeitschrift für wissenschaft.  Zoologie,’ B. xxviii. 1877, p. 361.

{5}  ‘Gardeners’ Chronicle,’ April 17, 1869, p. 418.

{6}  Mr. Darwin’s attention was called by Professor Hensen to P. E.
Müller’s work on Humus in ‘Tidsskrift for Skovbrug,’ Band iii. Heft 1 and
2, Copenhagen, 1878.  He had, however, no opportunity of consulting
Müller’s work.  Dr. Müller published a second paper in 1884 in the same
periodical—a Danish journal of forestry.  His results have also been
published in German, in a volume entitled ‘Studien über die natürlichen
Humusformen, unter deren Einwirkung auf Vegetation und Boden,’ 8vo.,
Berlin, 1887.

{8a}  ‘Bidrag till Skandinaviens Oligochætfauna,’ 1871.

{8b}  ‘Die bis jetzt bekannten Arten aus der Familie der Regenwürmer,’
1845.

{9b}  There is even some reason to believe that pressure is actually
favourable to the growth of grasses, for Professor Buckman, who made many
observations on their growth in the experimental gardens of the Royal
Agricultural College, remarks (‘Gardeners’ Chronicle,’ 1854, p. 619):
“Another circumstance in the cultivation of grasses in the separate form
or small patches, is the impossibility of rolling or treading them
firmly, without which no pasture can continue good.”

{11}  I shall have occasion often to refer to M. Perrier’s admirable
memoir, ‘Organisation des Lombriciens terrestres’ in ‘Archives de Zoolog.
expér.’ tom. iii. 1874, p. 372.  C. F. Morren (‘De Lumbrici terrestris
Hist. Nat.’ 1829, p. 14) found that worms endured immersion for fifteen
to twenty days in summer, but that in winter they died when thus treated.

{12}  Morren, ‘De Lumbrici terrestris Hist. Nat.’ &c., 1829, p. 67.

{14}  ‘De Lumbrici terrestris Hist. Nat.’ &c., p. 14.

{17}  Histolog.  Untersuchungen über die Regenwürmer.  ‘Zeitschrift für
wissenschaft.  Zoologie,’ B. xix., 1869, p. 611.

{18a}  For instance, Mr. Bridgman and Mr. Newman (‘The Zoologist,’ vol.
vii. 1849, p. 2576), and some friends who observed worms for me.

{18b}  ‘Familie der Regenwürmer,’ 1845, p. 18.

{31}  ‘The Zoologist,’ vol. vii. 1849, p. 2576.

{32}  ‘Familie der Regenwürmer,’ p. 13.  Dr. Sturtevant states in the
‘New York Weekly Tribune’ (May 19, 1880) that he kept three worms in a
pot, which was allowed to become extremely dry; and these worms were
found “all entwined together, forming a round mass and in good
condition.”

{33}  ‘De Lumbrici terrestris Hist. Nat.’ p. 19.

{34}  ‘Archives de Zoologie expérimentale,’ tom. vii. 1878, p. 394.  When
I wrote the above passage, I was not aware that Krukenberg
(‘Untersuchungen a. d. physiol.  Inst. d. Univ.  Heidelberg,’ Bd. ii. p.
37, 1877) had previously investigated the digestive juice of Lumbricus.
He states that it contains a peptic, and diastatic, as well as a tryptic
ferment.

{35a}  On the action of the pancreatic ferment, see ‘A Text-Book of
Physiology,’ by Michael Foster, 2nd edit. pp. 198–203.  1878.

{35b}  Schmulewitsch, ‘Action des Sucs digestifs sur la Cellulose.’
Bull. de l’Acad. Imp. de St. Pétersbourg, tom. xxv. p. 549.  1879.

{40}  Claparède doubts whether saliva is secreted by worms: see
‘Zeitschrift für wissenschaft.  Zoologie,’ B. xix. 1869, p. 601.

{41a}  Perrier, ‘Archives de Zoolog. expér.’ July, 1874, pp. 416, 419.

{41b}  ‘Zeitschrift für wissenschaft.  Zoologie,’ B. xix, 1869, pp.
603–606.

{46}  De Vries, ‘Landwirth. Jahrbücher,’ 1881, p. 77.

{49}  M. Foster, ‘A Text-Book of Physiology,’ 2nd edit. 1878, p. 243.

{50}  M. Foster, _ut sup._ p. 200.

{53}  Claparède remarks (‘Zeitschrift für wisseuschaft.  Zoolog.’ B. 19,
1869, p. 602) that the pharynx appears from its structure to be adapted
for suction.

{58}  An account of her observations is given in the ‘Gardeners’
Chronicle,’ March 28th, 1868, p. 324.

{59a}  London’s ‘Gard. Mag.’ xvii. p. 216, as quoted in the ‘Catalogue of
the British Museum Worms,’ 1865, p. 327.

{59b}  ‘Familie der Regenwürmer,’ p. 19.

{79}  In these narrow triangles the apical angle is 9° 34', and the basal
angles 85° 13'.  In the broader triangles the apical angle is 19° 10' and
the basal angles 80° 25'.

{89a}  See his interesting work, ‘Souvenirs entomologiques,’ 1879, pp.
168–177.

{89b}  Möbius, ‘Die Bewegungen der Thiere,’ &c., 1873, p. 111.

{90}  ‘Annals and Mag. of N. History,’ series ii. vol. ix. 1852, p. 333.

{93}  ‘Archives de Zoolog. expér.’ tom. iii. 1874, p. 405.

{97}  I state this on the authority of Semper, ‘Reisen im Archipel der
Philippinen,’ Th. ii. 1877, p. 30.

{101}  Dr. King gave me some worms collected near Nice, which, as he
believes, had constructed these castings.  They were sent to M. Perrier,
who with great kindness examined and named them for me: they consisted of
_Perichæta affinis_, a native of Cochin China and of the Philippines; _P.
Luzonica_, a native of Luzon in the Philippines; and _P. Houlleti_, which
lives near Calcutta.  M. Perrier informs me that species of Perichæta
have been naturalized in the gardens near Montpellier and in Algiers.
Before I had any reason to suspect that the tower-like castings from Nice
had been formed by worms not endemic in the country, I was greatly
surprised to see how closely they resembled castings sent to me from near
Calcutta, where it is known that species of Perichæta abound.

{102}  ‘Zeitschrift für wissenschaft.  Zoolog.’  B. xxviii. 1877, p. 364.

{108}  ‘Zeitschrift für wissenschaft.  Zoolog.’ B. xxviii. 1877, p. 356.

{113}  Perrier, ‘Archives de Zoolog. expér.’ tom. 3, p. 378, 1874.

{126}  This case is given in a postscript to my paper in the ‘Transact.
Geolog. Soc.’  (Vol. v. p. 505), and contains a serious error, as in the
account received I mistook the figure 30 for 80.  The tenant, moreover,
formerly said that he had marled the field thirty years before, but was
now positive that this was done in 1809, that is twenty-eight years
before the first examination of the field by my friend.  The error, as
far as the figure 80 is concerned, was corrected in an article by me, in
the ‘Gardeners’ Chronicle,’ 1844, p. 218.

{128}  These pits or pipes are still in process of formation.  During the
last forty years I have seen or heard of five cases, in which a circular
space, several feet in diameter, suddenly fell in, leaving on the field
an open hole with perpendicular sides, some feet in depth.  This occurred
in one of my own fields, whilst it was being rolled, and the hinder
quarters of the shaft horse fell in; two or three cart-loads of rubbish
were required to fill up the hole.  The subsidence occurred where there
was a broad depression, as if the surface had fallen in at several former
periods.  I heard of a hole which must have been suddenly formed at the
bottom of a small shallow pool, where sheep had been washed during many
years, and into which a man thus occupied fell to his great terror.  The
rain-water over this whole district sinks perpendicularly into the
ground, but the chalk is more porous in certain places than in others.
Thus the drainage from the overlying clay is directed to certain points,
where a greater amount of calcareous matter is dissolved than elsewhere.
Even narrow open channels are sometimes formed in the solid chalk.  As
the chalk is slowly dissolved over the whole country, but more in some
parts than in others, the undissolved residue—that is the overlying mass
of red clay with flints,—likewise sinks slowly down, and tends to fill up
the pipes or cavities.  But the upper part of the red clay holds
together, aided probably by the roots of plants, for a longer time than
the lower parts, and thus forms a roof, which sooner or later falls in,
as in the above mentioned five cases.  The downward movement of the clay
may be compared with that of a glacier, but is incomparably slower; and
this movement accounts for a singular fact, namely, that the much
elongated flints which are embedded in the chalk in a nearly horizontal
position, are commonly found standing nearly or quite upright in the red
clay.  This fact is so common that the workmen assured me that this was
their natural position.  I roughly measured one which stood vertically,
and it was of the same length and of the same relative thickness as one
of my arms.  These elongated flints must get placed in their upright
position, on the same principle that a trunk of a tree left on a glacier
assumes a position parallel to the line of motion.  The flints in the
clay which form almost half its bulk, are very often broken, though not
rolled or abraded; and this may he accounted for by their mutual
pressure, whilst the whole mass is subsiding.  I may add that the chalk
here appears to have been originally covered in parts by a thin bed of
fine sand with some perfectly rounded flint pebbles, probably of Tertiary
age; for such sand often partly fills up the deeper pits or cavities in
the chalk.

{131}  S. W. Johnson, ‘How Crops Feed,’ 1870, p. 139.

{136a}  ‘Nature,’ November 1877, p. 28.

{136b}  ‘Proc. Phil. Soc.’ of Manchester, 1877, p. 247.

{138a}  ‘Trans. of the New Zealand Institute,’ vol. xii., 1880, p. 152.

{138b}  Mr. Lindsay Carnagie, in a letter (June 1838) to Sir C. Lyell,
remarks that Scotch farmers are afraid of putting lime on ploughed land
until just before it is laid down for pasture, from a belief that it has
some tendency to sink.  He adds: “Some years since, in autumn, I laid
lime on an oat-stubble and ploughed it down; thus bringing it into
immediate contact with the dead vegetable matter, and securing its
thorough mixture through the means of all the subsequent operations of
fallow.  In consequence of the above prejudice, I was considered to have
committed a great fault; but the result was eminently successful, and the
practice was _partially_ followed.  By means of Mr. Darwin’s
observations, I think the prejudice will be removed.”

{139}  This conclusion, which, as we shall immediately see, is fully
justified, is of some little importance, as the so-called bench-stones,
which surveyors fix in the ground as a record of their levels, may in
time become false standards.  My son Horace intends at some future period
to ascertain how far this has occurred.

{147}  Mr. R. Mallet remarks (‘Quarterly Journal of Geolog. Soc.’ vol.
xxxiii., 1877, p. 745) that “the extent to which the ground beneath the
foundations of ponderous architectural structures, such as cathedral
towers, has been known to become compressed, is as remarkable as it is
instructive and curious.  The amount of depression in some cases may be
measured by feet.”  He instances the Tower of Pisa, but adds that it was
founded on “dense clay.”

{148}  ‘Zeitschrift für wissensch. Zoolog.’ Bd. xxviii., 1877, p. 360.

{149}  See Mr. Dancer’s paper in ‘Proc. Phil. Soc. of Manchester,’ 1877,
p. 248.

{166a}  ‘Leçons de Géologie pratique,’ 1845, p. 142.

{166b}  A short account of this discovery was published in ‘The Times’ of
January 2, 1878; and a fuller account in ‘The Builder,’ January 5, 1878.

{183}  Several accounts of these ruins have been published; the best is
by Mr. James Farrer in ‘Proc. Soc. of Antiquaries of Scotland,’ vol. vi.,
Part II., 1867, p. 278.  Also J. W. Grover, ‘Journal of the British Arch.
Assoc.’ June 1866.  Professor Buckman has likewise published a pamphlet,
‘Notes on the Roman Villa at Chedworth,’ 2nd edit. 1873 Cirencester.

{187}  These details are taken from the ‘Penny Cyclopædia,’ article
Hampshire.

{210}  “On the denudation of South Wales,” &c., ‘Memoirs of the
Geological Survey of Great Britain,’ vol. 1., p. 297, 1846.

{211}  ‘Geological Magazine,’ October and November, 1867, vol. iv. pp.
447 and 483.  Copious references on the subject are given in this
remarkable memoir.

{212}  A. Tylor “On changes of the sea-level,” &c., ‘ Philosophical Mag.’
(Ser. 4th) vol. v., 1853, p. 258.  Archibald Geikie, Transactions Geolog.
Soc. of Glasgow, vol. iii., p. 153 (read March, 1868).  Croll “On
Geological Time,” ‘Philosophical Mag.,’ May, August, and November, 1868.
See also Croll, ‘Climate and Time,’ 1875, Chap. XX.  For some recent
information on the amount of sediment brought down by rivers, see
‘Nature,’ Sept.  23rd, 1880.  Mr. T. Mellard Reade has published some
interesting articles on the astonishing amount of matter brought down in
solution by rivers.  See Address, Geolog. Soc., Liverpool, 1876–77.

{213}  “An account of the fine dust which often falls on Vessels in the
Atlantic Ocean,” Proc. Geolog. Soc. of London, June 4th, 1845.

{215}  For La Plata, see my ‘Journal of Researches,’ during the voyage of
the _Beagle_, 1845, p. 133.  Élie de Beaumont has given (‘Leçons de
Géolog. pratique,’ tom. I. 1845, p. 183) an excellent account of the
enormous quantity of dust which is transported in some countries.  I
cannot but think that Mr. Proctor has somewhat exaggerated (‘Pleasant
Ways in Science,’ 1879, p. 379) the agency of dust in a humid country
like Great Britain.  James Geikie has given (‘Prehistoric Europe,’ 1880,
p. 165) a full abstract of Richthofen’s views, which, however, he
disputes.

{217a}  These statements are taken from Hensen in ‘Zeitschrift für
wissenschaft. Zoologie.’ Bd. xxviii., 1877, p. 360.  Those with respect
to peat are taken from Mr. A. A. Julien in ‘Proc. American Assoc.
Science,’ 1879, p. 354.

{217b}  I have given some facts on the climate necessary or favourable
for the formation of peat, in my ‘Journal of Researches,’ 1845, p. 287.

{220}  A. A. Julien “On the Geological action of the Humus-acids,” ‘Proc.
American Assoc. Science,’ vol. xxviii., 1879, p. 311.  Also on “Chemical
erosion on Mountain Summits;” ‘New York Academy of Sciences,’ Oct. 14,
1878, as quoted in the ‘American Naturalist.’  See also, on this subject,
S. W. Johnson, ‘How Crops Feed,’ 1870, p. 138.

{222}  See, for references on this subject, S. W. Johnson, ‘How Crops
Feed,’ 1870, p. 326.

{223}  This statement is taken from Mr. Julien, ‘Proc. American Assoc.
Science,’ vol.  xxviii., 1879, p. 330.

{224a}  The preservative power of a layer of mould and turf is often
shown by the perfect state of the glacial scratches on rocks when first
uncovered.  Mr. J. Geikie maintains, in his last very interesting work
(‘Prehistoric Europe,’ 1881), that the more perfect scratches are
probably due to the last access of cold and increase of ice, during the
long-continued, intermittent glacial period.

{224b}  Many geologists have felt much surprise at the complete
disappearance of flints over wide and nearly level areas, from which the
chalk has been removed by subaerial denudation.  But the surface of every
flint is coated by an opaque modified layer, which will just yield to a
steel point, whilst the freshly fractured, translucent surface will not
thus yield.  The removal by atmospheric agencies of the outer modified
surfaces of freely exposed flints, though no doubt excessively slow,
together with the modification travelling inwards, will, as may be
suspected, ultimately lead to their complete disintegration,
notwithstanding that they appear to be so extremely durable.

{225a}  ‘Archives de Zoolog. expér.’ tom. iii. 1874, p. 409.

{225b}  ‘Nouvelles Archives du Muséum,’ tom. viii. 1872, pp.  95, 131.

{226}  Morren, in speaking of the earth in the alimentary canals of
worms, says, “præsepè cum lapillis commixtam vidi:” ‘De Lumbrici
terrestris Hist. Nat.’ &c., 1829, p. 16.

{227}  Perrier, ‘Archives de Zoolog. expér.’ tom. iii. 1874, p. 419.

{228a}  Morren, ‘De Lumbrici terrestris Hist. Nat.’ &c., p. 16.

{228b}  ‘Archives de Zoolog. expér.’ tom. iii. 1874, p. 418.

{234}  This conclusion reminds me of the vast amount of extremely fine
chalky mud which is found within the lagoons of many atolls, where the
sea is tranquil and waves cannot triturate the blocks of coral.  This mud
must, as I believe (‘The Structure and Distribution of Coral-Reefs,’ 2nd
edit. 1874, p. 19), be attributed to the innumerable annelids and other
animals which burrow into the dead coral, and to the fishes,
Holothurians, &c., which browse on the living corals.

{236}  Anniversary Address: ‘The Quarterly Journal of the Geological
Soc.’ May 1880, p. 59.

{244}  Mr. James Wallace has pointed out that it is necessary to take
into consideration the possibility of burrows being made at right angles
to the surface instead of vertically down, in which case the lateral
displacement of the soil would be increased.

{259}  ‘Elements of Geology,’ 1865, p. 20.

{265}  ‘Leçons de Géologie pratique, 1845; cinquième Leçon.  All Élie de
Beaumont’s arguments are admirably controverted by Prof. A. Geikie in his
essay in Transact. Geolog. Soc. of Glasgow, vol. iii. p. 153, 1868.

{266}  ‘Illustrations of the Huttonian Theory of the Earth,’ p. 107.

{269}  Mr. E. Tylor in his Presidential address (‘Journal of the
Anthropological Institute,’ May 1880, p. 451) remarks: “It appears from
several papers of the Berlin Society as to the German ‘high-fields’ or
‘heathen-fields’ (Hochäcker, and Heidenäcker) that they correspond much
in their situation on hills and wastes with the ‘elf-furrows’ of
Scotland, which popular mythology accounts for by the story of the fields
having been put under a Papal interdict, so that people took to
cultivating the hills.  There seems reason to suppose that, like the
tilled plots in the Swedish forest which tradition ascribes to the old
‘hackers,’ the German heathen-fields represent tillage by an ancient and
barbaric population.”

{284}  White of Selborne has some good remarks on the service performed
by worms in loosening, &c., the soil.  Edit, by L. Jenyns, 1843, p. 281.

{285}  ‘Zeitschrift für wissenschaft. Zoolog.’ B. xxviii. 1877, p. 360.
I have stated in the preface to the first Edition of this work, and in
the Zoology of the Voyage of the Beagle, that it was in consequence of
a wish expressed by Captain Fitz Roy, of having some scientific person
on board, accompanied by an offer from him of giving up part of his own
accommodations, that I volunteered my services, which received, through
the kindness of the hydrographer, Captain Beaufort, the sanction of the
Lords of the Admiralty.  As I feel that the opportunities which I
enjoyed of studying the Natural History of the different countries we
visited, have been wholly due to Captain Fitz Roy, I hope I may here be
permitted to repeat my expression of gratitude to him; and to add that,
during the five years we were together, I received from him the most
cordial friendship and steady assistance.  Both to Captain Fitz Roy and
to all the Officers of the Beagle [1] I shall ever feel most thankful
for the undeviating kindness with which I was treated during our long
voyage.

This volume contains, in the form of a Journal, a history of our
voyage, and a sketch of those observations in Natural History and
Geology, which I think will possess some interest for the general
reader.  I have in this edition largely condensed and corrected some
parts, and have added a little to others, in order to render the volume
more fitted for popular reading; but I trust that naturalists will
remember, that they must refer for details to the larger publications
which comprise the scientific results of the Expedition.  The Zoology
of the Voyage of the Beagle includes an account of the Fossil Mammalia,
by Professor Owen; of the Living Mammalia, by Mr. Waterhouse; of the
Birds, by Mr. Gould; of the Fish, by the Rev. L. Jenyns; and of the
Reptiles, by Mr. Bell.  I have appended to the descriptions of each
species an account of its habits and range.  These works, which I owe
to the high talents and disinterested zeal of the above distinguished
authors, could not have been undertaken, had it not been for the
liberality of the Lords Commissioners of Her Majesty's Treasury, who,
through the representation of the Right Honourable the Chancellor of
the Exchequer, have been pleased to grant a sum of one thousand pounds
towards defraying part of the expenses of publication.

I have myself published separate volumes on the 'Structure and
Distribution of Coral Reefs;' on the 'Volcanic Islands visited during
the Voyage of the Beagle;' and on the 'Geology of South America.' The
sixth volume of the 'Geological Transactions' contains two papers of
mine on the Erratic Boulders and Volcanic Phenomena of South America.
Messrs. Waterhouse, Walker, Newman, and White, have published several
able papers on the Insects which were collected, and I trust that many
others will hereafter follow.  The plants from the southern parts of
America will be given by Dr. J. Hooker, in his great work on the Botany
of the Southern Hemisphere.  The Flora of the Galapagos Archipelago is
the subject of a separate memoir by him, in the 'Linnean Transactions.'
The Reverend Professor Henslow has published a list of the plants
collected by me at the Keeling Islands; and the Reverend J. M. Berkeley
has described my cryptogamic plants.

I shall have the pleasure of acknowledging the great assistance which I
have received from several other naturalists, in the course of this and
my other works; but I must be here allowed to return my most sincere
thanks to the Reverend Professor Henslow, who, when I was an
undergraduate at Cambridge, was one chief means of giving me a taste
for Natural History,--who, during my absence, took charge of the
collections I sent home, and by his correspondence directed my
endeavours,--and who, since my return, has constantly rendered me every
assistance which the kindest friend could offer.

DOWN, BROMLEY, KENT, June 9, 1845

[1] I must take this opportunity of returning my sincere thanks to Mr.
Bynoe, the surgeon of the Beagle, for his very kind attention to me
when I was ill at Valparaiso.



THE VOYAGE OF THE BEAGLE



CHAPTER I

ST. JAGO--CAPE DE VERD ISLANDS

Porto Praya--Ribeira Grande--Atmospheric Dust with Infusoria--Habits of
a Sea-slug and Cuttle-fish--St. Paul's Rocks, non-volcanic--Singular
Incrustations--Insects the first Colonists of Islands--Fernando
Noronha--Bahia--Burnished Rocks--Habits of a Diodon--Pelagic Confervae
and Infusoria--Causes of discoloured Sea.


AFTER having been twice driven back by heavy southwestern gales, Her
Majesty's ship Beagle, a ten-gun brig, under the command of Captain
Fitz Roy, R. N., sailed from Devonport on the 27th of December, 1831.
The object of the expedition was to complete the survey of Patagonia
and Tierra del Fuego, commenced under Captain King in 1826 to 1830,--to
survey the shores of Chile, Peru, and of some islands in the
Pacific--and to carry a chain of chronometrical measurements round the
World. On the 6th of January we reached Teneriffe, but were prevented
landing, by fears of our bringing the cholera: the next morning we saw
the sun rise behind the rugged outline of the Grand Canary island, and
suddenly illuminate the Peak of Teneriffe, whilst the lower parts were
veiled in fleecy clouds.  This was the first of many delightful days
never to be forgotten. On the 16th of January, 1832, we anchored at
Porto Praya, in St. Jago, the chief island of the Cape de Verd
archipelago.

The neighbourhood of Porto Praya, viewed from the sea, wears a desolate
aspect.  The volcanic fires of a past age, and the scorching heat of a
tropical sun, have in most places rendered the soil unfit for
vegetation.  The country rises in successive steps of table-land,
interspersed with some truncate conical hills, and the horizon is
bounded by an irregular chain of more lofty mountains.  The scene, as
beheld through the hazy atmosphere of this climate, is one of great
interest; if, indeed, a person, fresh from sea, and who has just
walked, for the first time, in a grove of cocoa-nut trees, can be a
judge of anything but his own happiness.  The island would generally be
considered as very uninteresting, but to anyone accustomed only to an
English landscape, the novel aspect of an utterly sterile land
possesses a grandeur which more vegetation might spoil.  A single green
leaf can scarcely be discovered over wide tracts of the lava plains;
yet flocks of goats, together with a few cows, contrive to exist.  It
rains very seldom, but during a short portion of the year heavy
torrents fall, and immediately afterwards a light vegetation springs
out of every crevice.  This soon withers; and upon such naturally
formed hay the animals live.  It had not now rained for an entire year.
When the island was discovered, the immediate neighbourhood of Porto
Praya was clothed with trees, [1] the reckless destruction of which has
caused here, as at St. Helena, and at some of the Canary islands,
almost entire sterility.  The broad, flat-bottomed valleys, many of
which serve during a few days only in the season as water-courses, are
clothed with thickets of leafless bushes.  Few living creatures inhabit
these valleys.  The commonest bird is a kingfisher (Dacelo Iagoensis),
which tamely sits on the branches of the castor-oil plant, and thence
darts on grasshoppers and lizards.  It is brightly coloured, but not so
beautiful as the European species: in its flight, manners, and place of
habitation, which is generally in the driest valley, there is also a
wide difference.

One day, two of the officers and myself rode to Ribeira Grande, a
village a few miles eastward of Porto Praya.  Until we reached the
valley of St. Martin, the country presented its usual dull brown
appearance; but here, a very small rill of water produces a most
refreshing margin of luxuriant vegetation.  In the course of an hour we
arrived at Ribeira Grande, and were surprised at the sight of a large
ruined fort and cathedral.  This little town, before its harbour was
filled up, was the principal place in the island: it now presents a
melancholy, but very picturesque appearance.  Having procured a black
Padre for a guide, and a Spaniard who had served in the Peninsular war
as an interpreter, we visited a collection of buildings, of which an
ancient church formed the principal part.  It is here the governors and
captain-generals of the islands have been buried.  Some of the
tombstones recorded dates of the sixteenth century. [2]

The heraldic ornaments were the only things in this retired place that
reminded us of Europe.  The church or chapel formed one side of a
quadrangle, in the middle of which a large clump of bananas were
growing.  On another side was a hospital, containing about a dozen
miserable-looking inmates.

We returned to the Venda to eat our dinners.  A considerable number of
men, women, and children, all as black as jet, collected to watch us.
Our companions were extremely merry; and everything we said or did was
followed by their hearty laughter.  Before leaving the town we visited
the cathedral.  It does not appear so rich as the smaller church, but
boasts of a little organ, which sent forth singularly inharmonious
cries.  We presented the black priest with a few shillings, and the
Spaniard, patting him on the head, said, with much candour, he thought
his colour made no great difference.  We then returned, as fast as the
ponies would go, to Porto Praya.

Another day we rode to the village of St. Domingo, situated near the
centre of the island.  On a small plain which we crossed, a few stunted
acacias were growing; their tops had been bent by the steady
trade-wind, in a singular manner--some of them even at right angles to
their trunks. The direction of the branches was exactly N. E. by N.,
and S. W. by S., and these natural vanes must indicate the prevailing
direction of the force of the trade-wind.  The travelling had made so
little impression on the barren soil, that we here missed our track,
and took that to Fuentes.  This we did not find out till we arrived
there; and we were afterwards glad of our mistake.  Fuentes is a pretty
village, with a small stream; and everything appeared to prosper well,
excepting, indeed, that which ought to do so most--its inhabitants. The
black children, completely naked, and looking very wretched, were
carrying bundles of firewood half as big as their own bodies.

Near Fuentes we saw a large flock of guinea-fowl--probably fifty or
sixty in number.  They were extremely wary, and could not be
approached.  They avoided us, like partridges on a rainy day in
September, running with their heads cocked up; and if pursued, they
readily took to the wing.

The scenery of St. Domingo possesses a beauty totally unexpected, from
the prevalent gloomy character of the rest of the island.  The village
is situated at the bottom of a valley, bounded by lofty and jagged
walls of stratified lava. The black rocks afford a most striking
contrast with the bright green vegetation, which follows the banks of a
little stream of clear water.  It happened to be a grand feast-day, and
the village was full of people.  On our return we overtook a party of
about twenty young black girls, dressed in excellent taste; their black
skins and snow-white linen being set off by coloured turbans and large
shawls.  As soon as we approached near, they suddenly all turned round,
and covering the path with their shawls, sung with great energy a wild
song, beating time with their hands upon their legs. We threw them some
vintems, which were received with screams of laughter, and we left them
redoubling the noise of their song.

One morning the view was singularly clear; the distant mountains being
projected with the sharpest outline on a heavy bank of dark blue
clouds.  Judging from the appearance, and from similar cases in
England, I supposed that the air was saturated with moisture.  The
fact, however, turned out quite the contrary.  The hygrometer gave a
difference of 29.6 degs., between the temperature of the air, and the
point at which dew was precipitated.  This difference was nearly double
that which I had observed on the previous mornings.  This unusual
degree of atmospheric dryness was accompanied by continual flashes of
lightning.  Is it not an uncommon case, thus to find a remarkable
degree of aerial transparency with such a state of weather?

Generally the atmosphere is hazy; and this is caused by the falling of
impalpably fine dust, which was found to have slightly injured the
astronomical instruments.  The morning before we anchored at Porto
Praya, I collected a little packet of this brown-coloured fine dust,
which appeared to have been filtered from the wind by the gauze of the
vane at the mast-head.  Mr. Lyell has also given me four packets of
dust which fell on a vessel a few hundred miles northward of these
islands.  Professor Ehrenberg [3] finds that this dust consists in
great part of infusoria with siliceous shields, and of the siliceous
tissue of plants.  In five little packets which I sent him, he has
ascertained no less than sixty-seven different organic forms!  The
infusoria, with the exception of two marine species, are all
inhabitants of fresh-water.  I have found no less than fifteen
different accounts of dust having fallen on vessels when far out in the
Atlantic.  From the direction of the wind whenever it has fallen, and
from its having always fallen during those months when the harmattan is
known to raise clouds of dust high into the atmosphere, we may feel
sure that it all comes from Africa.  It is, however, a very singular
fact, that, although Professor Ehrenberg knows many species of
infusoria peculiar to Africa, he finds none of these in the dust which
I sent him. On the other hand, he finds in it two species which
hitherto he knows as living only in South America.  The dust falls in
such quantities as to dirty everything on board, and to hurt people's
eyes; vessels even have run on shore owing to the obscurity of the
atmosphere.  It has often fallen on ships when several hundred, and
even more than a thousand miles from the coast of Africa, and at points
sixteen hundred miles distant in a north and south direction.  In some
dust which was collected on a vessel three hundred miles from the land,
I was much surprised to find particles of stone above the thousandth of
an inch square, mixed with finer matter.  After this fact one need not
be surprised at the diffusion of the far lighter and smaller sporules
of cryptogamic plants.

The geology of this island is the most interesting part of its natural
history.  On entering the harbour, a perfectly horizontal white band,
in the face of the sea cliff, may be seen running for some miles along
the coast, and at the height of about forty-five feet above the water.
Upon examination this white stratum is found to consist of calcareous
matter with numerous shells embedded, most or all of which now exist on
the neighbouring coast.  It rests on ancient volcanic rocks, and has
been covered by a stream of basalt, which must have entered the sea
when the white shelly bed was lying at the bottom.  It is interesting
to trace the changes produced by the heat of the overlying lava, on the
friable mass, which in parts has been converted into a crystalline
limestone, and in other parts into a compact spotted stone Where the
lime has been caught up by the scoriaceous fragments of the lower
surface of the stream, it is converted into groups of beautifully
radiated fibres resembling arragonite. The beds of lava rise in
successive gently-sloping plains, towards the interior, whence the
deluges of melted stone have originally proceeded.  Within historical
times, no signs of volcanic activity have, I believe, been manifested
in any part of St. Jago.  Even the form of a crater can but rarely be
discovered on the summits of the many red cindery hills; yet the more
recent streams can be distinguished on the coast, forming lines of
cliffs of less height, but stretching out in advance of those belonging
to an older series: the height of the cliffs thus affording a rude
measure of the age of the streams.

During our stay, I observed the habits of some marine animals.  A large
Aplysia is very common.  This sea-slug is about five inches long; and
is of a dirty yellowish colour veined with purple.  On each side of the
lower surface, or foot, there is a broad membrane, which appears
sometimes to act as a ventilator, in causing a current of water to flow
over the dorsal branchiae or lungs.  It feeds on the delicate sea-weeds
which grow among the stones in muddy and shallow water; and I found in
its stomach several small pebbles, as in the gizzard of a bird.  This
slug, when disturbed, emits a very fine purplish-red fluid, which
stains the water for the space of a foot around.  Besides this means of
defence, an acrid secretion, which is spread over its body, causes a
sharp, stinging sensation, similar to that produced by the Physalia, or
Portuguese man-of-war.

I was much interested, on several occasions, by watching the habits of
an Octopus, or cuttle-fish.  Although common in the pools of water left
by the retiring tide, these animals were not easily caught.  By means
of their long arms and suckers, they could drag their bodies into very
narrow crevices; and when thus fixed, it required great force to remove
them.  At other times they darted tail first, with the rapidity of an
arrow, from one side of the pool to the other, at the same instant
discolouring the water with a dark chestnut-brown ink.  These animals
also escape detection by a very extraordinary, chameleon-like power of
changing their colour. They appear to vary their tints according to the
nature of the ground over which they pass: when in deep water, their
general shade was brownish purple, but when placed on the land, or in
shallow water, this dark tint changed into one of a yellowish green.
The colour, examined more carefully, was a French grey, with numerous
minute spots of bright yellow: the former of these varied in intensity;
the latter entirely disappeared and appeared again by turns.  These
changes were effected in such a manner, that clouds, varying in tint
between a hyacinth red and a chestnut-brown, [4] were continually
passing over the body.  Any part, being subjected to a slight shock of
galvanism, became almost black: a similar effect, but in a less degree,
was produced by scratching the skin with a needle.  These clouds, or
blushes as they may be called, are said to be produced by the alternate
expansion and contraction of minute vesicles containing variously
coloured fluids. [5]

This cuttle-fish displayed its chameleon-like power both during the act
of swimming and whilst remaining stationary at the bottom.  I was much
amused by the various arts to escape detection used by one individual,
which seemed fully aware that I was watching it.  Remaining for a time
motionless, it would then stealthily advance an inch or two, like a cat
after a mouse; sometimes changing its colour: it thus proceeded, till
having gained a deeper part, it darted away, leaving a dusky train of
ink to hide the hole into which it had crawled.

While looking for marine animals, with my head about two feet above the
rocky shore, I was more than once saluted by a jet of water,
accompanied by a slight grating noise.  At first I could not think what
it was, but afterwards I found out that it was this cuttle-fish, which,
though concealed in a hole, thus often led me to its discovery.  That
it possesses the power of ejecting water there is no doubt, and it
appeared to me that it could certainly take good aim by directing the
tube or siphon on the under side of its body.  From the difficulty
which these animals have in carrying their heads, they cannot crawl
with ease when placed on the ground.  I observed that one which I kept
in the cabin was slightly phosphorescent in the dark.

ST. PAUL'S ROCKS.--In crossing the Atlantic we hove-to during the
morning of February 16th, close to the island of St. Paul's.  This
cluster of rocks is situated in 0 degs. 58' north latitude, and 29
degs. 15' west longitude.  It is 540 miles distant from the coast of
America, and 350 from the island of Fernando Noronha.  The highest
point is only fifty feet above the level of the sea, and the entire
circumference is under three-quarters of a mile.  This small point
rises abruptly out of the depths of the ocean.  Its mineralogical
constitution is not simple; in some parts the rock is of a cherty, in
others of a felspathic nature, including thin veins of serpentine.  It
is a remarkable fact, that all the many small islands, lying far from
any continent, in the Pacific, Indian, and Atlantic Oceans, with the
exception of the Seychelles and this little point of rock, are, I
believe, composed either of coral or of erupted matter.  The volcanic
nature of these oceanic islands is evidently an extension of that law,
and the effect of those same causes, whether chemical or mechanical,
from which it results that a vast majority of the volcanoes now in
action stand either near sea-coasts or as islands in the midst of the
sea.

The rocks of St. Paul appear from a distance of a brilliantly white
colour.  This is partly owing to the dung of a vast multitude of
seafowl, and partly to a coating of a hard glossy substance with a
pearly lustre, which is intimately united to the surface of the rocks.
This, when examined with a lens, is found to consist of numerous
exceedingly thin layers, its total thickness being about the tenth of
an inch.  It contains much animal matter, and its origin, no doubt, is
due to the action of the rain or spray on the birds' dung.  Below some
small masses of guano at Ascension, and on the Abrolhos Islets, I found
certain stalactitic branching bodies, formed apparently in the same
manner as the thin white coating on these rocks.  The branching bodies
so closely resembled in general appearance certain nulliporae (a family
of hard calcareous sea-plants), that in lately looking hastily over my
collection I did not perceive the difference.  The globular extremities
of the branches are of a pearly texture, like the enamel of teeth, but
so hard as just to scratch plate-glass.  I may here mention, that on a
part of the coast of Ascension, where there is a vast accumulation of
shelly sand, an incrustation is deposited on the tidal rocks by the
water of the sea, resembling, as represented in the woodcut, certain
cryptogamic plants (Marchantiae) often seen on damp walls.  The surface
of the fronds is beautifully glossy; and those parts formed where fully
exposed to the light are of a jet black colour, but those shaded under
ledges are only grey. I have shown specimens of this incrustation to
several geologists, and they all thought that they were of volcanic or
igneous origin!  In its hardness and translucency--in its polish, equal
to that of the finest oliva-shell--in the bad smell given out, and loss
of colour under the blowpipe--it shows a close similarity with living
sea-shells.  Moreover, in sea-shells, it is known that the parts
habitually covered and shaded by the mantle of the animal, are of a
paler colour than those fully exposed to the light, just as is the case
with this incrustation.  When we remember that lime, either as a
phosphate or carbonate, enters into the composition of the hard parts,
such as bones and shells, of all living animals, it is an interesting
physiological fact [6] to find substances harder than the enamel of
teeth, and coloured surfaces as well polished as those of a fresh
shell, reformed through inorganic means from dead organic
matter--mocking, also, in shape, some of the lower vegetable
productions.

We found on St. Paul's only two kinds of birds--the booby and the
noddy.  The former is a species of gannet, and the latter a tern.  Both
are of a tame and stupid disposition, and are so unaccustomed to
visitors, that I could have killed any number of them with my
geological hammer. The booby lays her eggs on the bare rock; but the
tern makes a very simple nest with sea-weed.  By the side of many of
these nests a small flying-fish was placed; which I suppose, had been
brought by the male bird for its partner.  It was amusing to watch how
quickly a large and active crab (Graspus), which inhabits the crevices
of the rock, stole the fish from the side of the nest, as soon as we
had disturbed the parent birds.  Sir W. Symonds, one of the few persons
who have landed here, informs me that he saw the crabs dragging even
the young birds out of their nests, and devouring them.  Not a single
plant, not even a lichen, grows on this islet; yet it is inhabited by
several insects and spiders.  The following list completes, I believe,
the terrestrial fauna: a fly (Olfersia) living on the booby, and a tick
which must have come here as a parasite on the birds; a small brown
moth, belonging to a genus that feeds on feathers; a beetle (Quedius)
and a woodlouse from beneath the dung; and lastly, numerous spiders,
which I suppose prey on these small attendants and scavengers of the
water-fowl.  The often repeated description of the stately palm and
other noble tropical plants, then birds, and lastly man, taking
possession of the coral islets as soon as formed, in the Pacific, is
probably not correct; I fear it destroys the poetry of this story, that
feather and dirt-feeding and parasitic insects and spiders should be
the first inhabitants of newly formed oceanic land.

The smallest rock in the tropical seas, by giving a foundation for the
growth of innumerable kinds of sea-weed and compound animals, supports
likewise a large number of fish. The sharks and the seamen in the boats
maintained a constant struggle which should secure the greater share of
the prey caught by the fishing-lines.  I have heard that a rock near
the Bermudas, lying many miles out at sea, and at a considerable depth,
was first discovered by the circumstance of fish having been observed
in the neighbourhood.

FERNANDO NORONHA, Feb. 20th.--As far as I was enabled to observe,
during the few hours we stayed at this place, the constitution of the
island is volcanic, but probably not of a recent date.  The most
remarkable feature is a conical hill, about one thousand feet high, the
upper part of which is exceedingly steep, and on one side overhangs its
base.  The rock is phonolite, and is divided into irregular columns. On
viewing one of these isolated masses, at first one is inclined to
believe that it has been suddenly pushed up in a semi-fluid state.  At
St. Helena, however, I ascertained that some pinnacles, of a nearly
similar figure and constitution, had been formed by the injection of
melted rock into yielding strata, which thus had formed the moulds for
these gigantic obelisks.  The whole island is covered with wood; but
from the dryness of the climate there is no appearance of luxuriance.
Half-way up the mountain, some great masses of the columnar rock,
shaded by laurel-like trees, and ornamented by others covered with fine
pink flowers but without a single leaf, gave a pleasing effect to the
nearer parts of the scenery.

BAHIA, OR SAN SALVADOR.  BRAZIL, Feb. 29th.--The day has passed
delightfully.  Delight itself, however, is a weak term to express the
feelings of a naturalist who, for the first time, has wandered by
himself in a Brazilian forest.  The elegance of the grasses, the
novelty of the parasitical plants, the beauty of the flowers, the
glossy green of the foliage, but above all the general luxuriance of
the vegetation, filled me with admiration.  A most paradoxical mixture
of sound and silence pervades the shady parts of the wood.  The noise
from the insects is so loud, that it may be heard even in a vessel
anchored several hundred yards from the shore; yet within the recesses
of the forest a universal silence appears to reign.  To a person fond
of natural history, such a day as this brings with it a deeper pleasure
than he can ever hope to experience again.  After wandering about for
some hours, I returned to the landing-place; but, before reaching it, I
was overtaken by a tropical storm.  I tried to find shelter under a
tree, which was so thick that it would never have been penetrated by
common English rain; but here, in a couple of minutes, a little torrent
flowed down the trunk. It is to this violence of the rain that we must
attribute the verdure at the bottom of the thickest woods: if the
showers were like those of a colder climate, the greater part would be
absorbed or evaporated before it reached the ground.  I will not at
present attempt to describe the gaudy scenery of this noble bay,
because, in our homeward voyage, we called here a second time, and I
shall then have occasion to remark on it.

Along the whole coast of Brazil, for a length of at least 2000 miles,
and certainly for a considerable space inland, wherever solid rock
occurs, it belongs to a granitic formation. The circumstance of this
enormous area being constituted of materials which most geologists
believe to have been crystallized when heated under pressure, gives
rise to many curious reflections.  Was this effect produced beneath the
depths of a profound ocean? or did a covering of strata formerly extend
over it, which has since been removed? Can we believe that any power,
acting for a time short of infinity, could have denuded the granite
over so many thousand square leagues?

On a point not far from the city, where a rivulet entered the sea, I
observed a fact connected with a subject discussed by Humboldt. [7] At
the cataracts of the great rivers Orinoco, Nile, and Congo, the
syenitic rocks are coated by a black substance, appearing as if they
had been polished with plumbago.  The layer is of extreme thinness; and
on analysis by Berzelius it was found to consist of the oxides of
manganese and iron.  In the Orinoco it occurs on the rocks periodically
washed by the floods, and in those parts alone where the stream is
rapid; or, as the Indians say, "the rocks are black where the waters
are white." Here the coating is of a rich brown instead of a black
colour, and seems to be composed of ferruginous matter alone.  Hand
specimens fail to give a just idea of these brown burnished stones
which glitter in the sun's rays.  They occur only within the limits of
the tidal waves; and as the rivulet slowly trickles down, the surf must
supply the polishing power of the cataracts in the great rivers.  In
like manner, the rise and fall of the tide probably answer to the
periodical inundations; and thus the same effects are produced under
apparently different but really similar circumstances.  The origin,
however, of these coatings of metallic oxides, which seem as if
cemented to the rocks, is not understood; and no reason, I believe, can
be assigned for their thickness remaining the same.

One day I was amused by watching the habits of the Diodon antennatus,
which was caught swimming near the shore.  This fish, with its flabby
skin, is well known to possess the singular power of distending itself
into a nearly spherical form.  After having been taken out of water for
a short time, and then again immersed in it, a considerable quantity
both of water and air is absorbed by the mouth, and perhaps likewise by
the branchial orifices.  This process is effected by two methods: the
air is swallowed, and is then forced into the cavity of the body, its
return being prevented by a muscular contraction which is externally
visible: but the water enters in a gentle stream through the mouth,
which is kept wide open and motionless; this latter action must,
therefore, depend on suction.  The skin about the abdomen is much
looser than that on the back; hence, during the inflation, the lower
surface becomes far more distended than the upper; and the fish, in
consequence, floats with its back downwards.  Cuvier doubts whether the
Diodon in this position is able to swim; but not only can it thus move
forward in a straight line, but it can turn round to either side.  This
latter movement is effected solely by the aid of the pectoral fins; the
tail being collapsed, and not used.  From the body being buoyed up with
so much air, the branchial openings are out of water, but a stream
drawn in by the mouth constantly flows through them.

The fish, having remained in this distended state for a short time,
generally expelled the air and water with considerable force from the
branchial apertures and mouth.  It could emit, at will, a certain
portion of the water, and it appears, therefore, probable that this
fluid is taken in partly for the sake of regulating its specific
gravity.  This Diodon possessed several means of defence.  It could
give a severe bite, and could eject water from its mouth to some
distance, at the same time making a curious noise by the movement of
its jaws.  By the inflation of its body, the papillae, with which the
skin is covered, become erect and pointed.  But the most curious
circumstance is, that it secretes from the skin of its belly, when
handled, a most beautiful carmine-red fibrous matter, which stains
ivory and paper in so permanent a manner that the tint is retained with
all its brightness to the present day: I am quite ignorant of the
nature and use of this secretion.  I have heard from Dr. Allan of
Forres, that he has frequently found a Diodon, floating alive and
distended, in the stomach of the shark, and that on several occasions
he has known it eat its way, not only through the coats of the stomach,
but through the sides of the monster, which has thus been killed.  Who
would ever have imagined that a little soft fish could have destroyed
the great and savage shark?

March 18th.--We sailed from Bahia.  A few days afterwards, when not far
distant from the Abrolhos Islets, my attention was called to a
reddish-brown appearance in the sea.  The whole surface of the water,
as it appeared under a weak lens, seemed as if covered by chopped bits
of hay, with their ends jagged.  These are minute cylindrical
confervae, in bundles or rafts of from twenty to sixty in each.  Mr.
Berkeley informs me that they are the same species (Trichodesmium
erythraeum) with that found over large spaces in the Red Sea, and
whence its name of Red Sea is derived. [8] Their numbers must be
infinite: the ship passed through several bands of them, one of which
was about ten yards wide, and, judging from the mud-like colour of the
water, at least two and a half miles long.  In almost every long voyage
some account is given of these confervae.  They appear especially
common in the sea near Australia; and off Cape Leeuwin I found an
allied but smaller and apparently different species.  Captain Cook, in
his third voyage, remarks, that the sailors gave to this appearance the
name of sea-sawdust.

Near Keeling Atoll, in the Indian Ocean, I observed many little masses
of confervae a few inches square, consisting of long cylindrical
threads of excessive thinness, so as to be barely visible to the naked
eye, mingled with other rather larger bodies, finely conical at both
ends.  Two of these are shown in the woodcut united together.  They
vary in length from .04 to .06, and even to .08 of an inch in length;
and in diameter from .006 to .008 of an inch.  Near one extremity of
the cylindrical part, a green septum, formed of granular matter, and
thickest in the middle, may generally be seen.  This, I believe, is the
bottom of a most delicate, colourless sac, composed of a pulpy
substance, which lines the exterior case, but does not extend within
the extreme conical points.  In some specimens, small but perfect
spheres of brownish granular matter supplied the places of the septa;
and I observed the curious process by which they were produced.  The
pulpy matter of the internal coating suddenly grouped itself into
lines, some of which assumed a form radiating from a common centre; it
then continued, with an irregular and rapid movement, to contract
itself, so that in the course of a second the whole was united into a
perfect little sphere, which occupied the position of the septum at one
end of the now quite hollow case. The formation of the granular sphere
was hastened by any accidental injury.  I may add, that frequently a
pair of these bodies were attached to each other, as represented above,
cone beside cone, at that end where the septum occurs.

I will add here a few other observations connected with the
discoloration of the sea from organic causes.  On the coast of Chile, a
few leagues north of Concepcion, the Beagle one day passed through
great bands of muddy water, exactly like that of a swollen river; and
again, a degree south of Valparaiso, when fifty miles from the land,
the same appearance was still more extensive.  Some of the water placed
in a glass was of a pale reddish tint; and, examined under a
microscope, was seen to swarm with minute animalcula darting about, and
often exploding.  Their shape is oval, and contracted in the middle by
a ring of vibrating curved ciliae.  It was, however, very difficult to
examine them with care, for almost the instant motion ceased, even
while crossing the field of vision, their bodies burst.  Sometimes both
ends burst at once, sometimes only one, and a quantity of coarse,
brownish, granular matter was ejected.  The animal an instant before
bursting expanded to half again its natural size; and the explosion
took place about fifteen seconds after the rapid progressive motion had
ceased: in a few cases it was preceded for a short interval by a
rotatory movement on the longer axis.  About two minutes after any
number were isolated in a drop of water, they thus perished. The
animals move with the narrow apex forwards, by the aid of their
vibratory ciliae, and generally by rapid starts. They are exceedingly
minute, and quite invisible to the naked eye, only covering a space
equal to the square of the thousandth of an inch.  Their numbers were
infinite; for the smallest drop of water which I could remove contained
very many.  In one day we passed through two spaces of water thus
stained, one of which alone must have extended over several square
miles.  What incalculable numbers of these microscopical animals!  The
colour of the water, as seen at some distance, was like that of a river
which has flowed through a red clay district, but under the shade of
the vessel's side it was quite as dark as chocolate.  The line where
the red and blue water joined was distinctly defined. The weather for
some days previously had been calm, and the ocean abounded, to an
unusual degree, with living creatures. [9]

In the sea around Tierra del Fuego, and at no great distance from the
land, I have seen narrow lines of water of a bright red colour, from
the number of crustacea, which somewhat resemble in form large prawns.
The sealers call them whale-food.  Whether whales feed on them I do not
know; but terns, cormorants, and immense herds of great unwieldy seals
derive, on some parts of the coast, their chief sustenance from these
swimming crabs.  Seamen invariably attribute the discoloration of the
water to spawn; but I found this to be the case only on one occasion.
At the distance of several leagues from the Archipelago of the
Galapagos, the ship sailed through three strips of a dark yellowish, or
mud-like water; these strips were some miles long, but only a few yards
wide, and they were separated from the surrounding water by a sinuous
yet distinct margin. The colour was caused by little gelatinous balls,
about the fifth of an inch in diameter, in which numerous minute
spherical ovules were imbedded: they were of two distinct kinds, one
being of a reddish colour and of a different shape from the other.  I
cannot form a conjecture as to what two kinds of animals these
belonged.  Captain Colnett remarks, that this appearance is very common
among the Galapagos Islands, and that the directions of the bands
indicate that of the currents; in the described case, however, the line
was caused by the wind.  The only other appearance which I have to
notice, is a thin oily coat on the water which displays iridescent
colours.  I saw a considerable tract of the ocean thus covered on the
coast of Brazil; the seamen attributed it to the putrefying carcase of
some whale, which probably was floating at no great distance.  I do not
here mention the minute gelatinous particles, hereafter to be referred
to, which are frequently dispersed throughout the water, for they are
not sufficiently abundant to create any change of colour.

There are two circumstances in the above accounts which appear
remarkable: first, how do the various bodies which form the bands with
defined edges keep together?  In the case of the prawn-like crabs,
their movements were as co-instantaneous as in a regiment of soldiers;
but this cannot happen from anything like voluntary action with the
ovules, or the confervae, nor is it probable among the infusoria.
Secondly, what causes the length and narrowness of the bands?  The
appearance so much resembles that which may be seen in every torrent,
where the stream uncoils into long streaks the froth collected in the
eddies, that I must attribute the effect to a similar action either of
the currents of the air or sea.  Under this supposition we must believe
that the various organized bodies are produced in certain favourable
places, and are thence removed by the set of either wind or water.  I
confess, however, there is a very great difficulty in imagining any one
spot to be the birthplace of the millions of millions of animalcula and
confervae: for whence come the germs at such points?--the parent bodies
having been distributed by the winds and waves over the immense ocean.
But on no other hypothesis can I understand their linear grouping.  I
may add that Scoresby remarks that green water abounding with pelagic
animals is invariably found in a certain part of the Arctic Sea.

[1] I state this on the authority of Dr. E. Dieffenbach, in his German
translation of the first edition of this Journal.

[2] The Cape de Verd Islands were discovered in 1449. There was a
tombstone of a bishop with the date of 1571; and a crest of a hand and
dagger, dated 1497.

[3] I must take this opportunity of acknowledging the great kindness
with which this illustrious naturalist has examined many of my
specimens.  I have sent (June, 1845) a full account of the falling of
this dust to the Geological Society.

[4] So named according to Patrick Symes's nomenclature.

[5] See Encyclop. of Anat. and Physiol., article Cephalopoda

[6] Mr. Horner and Sir David Brewster have described (Philosophical
Transactions, 1836, p. 65) a singular "artificial substance resembling
shell." It is deposited in fine, transparent, highly polished,
brown-coloured laminae, possessing peculiar optical properties, on the
inside of a vessel, in which cloth, first prepared with glue and then
with lime, is made to revolve rapidly in water.  It is much softer,
more transparent, and contains more animal matter, than the natural
incrustation at Ascension; but we here again see the strong tendency
which carbonate of lime and animal matter evince to form a solid
substance allied to shell.

[7] Pers. Narr., vol. v., pt. 1., p. 18.

[8] M. Montagne, in Comptes Rendus, etc., Juillet, 1844; and Annal. des
Scienc. Nat., Dec. 1844

[9] M. Lesson (Voyage de la Coquille, tom. i., p. 255) mentions red
water off Lima, apparently produced by the same cause. Peron, the
distinguished naturalist, in the Voyage aux Terres Australes, gives no
less than twelve references to voyagers who have alluded to the
discoloured waters of the sea (vol. ii. p. 239).  To the references
given by Peron may be added, Humboldt's Pers. Narr., vol. vi. p. 804;
Flinder's Voyage, vol. i. p. 92; Labillardiere, vol. i. p. 287; Ulloa's
Voyage; Voyage of the Astrolabe and of the Coquille; Captain King's
Survey of Australia, etc.



CHAPTER II

RIO DE JANEIRO

Rio de Janeiro--Excursion north of Cape Frio--Great
Evaporation--Slavery--Botofogo Bay--Terrestrial Planariae--Clouds on
the Corcovado--Heavy Rain--Musical Frogs--Phosphorescent
Insects--Elater, springing powers of--Blue Haze--Noise made by a
Butterfly--Entomology--Ants--Wasp killing a Spider--Parasitical
Spider--Artifices of an Epeira--Gregarious Spider--Spider with an
unsymmetrical Web.


APRIL 4th to July 5th, 1832.--A few days after our arrival I became
acquainted with an Englishman who was going to visit his estate,
situated rather more than a hundred miles from the capital, to the
northward of Cape Frio.  I gladly accepted his kind offer of allowing
me to accompany him.

April 8th.--Our party amounted to seven.  The first stage was very
interesting.  The day was powerfully hot, and as we passed through the
woods, everything was motionless, excepting the large and brilliant
butterflies, which lazily fluttered about.  The view seen when crossing
the hills behind Praia Grande was most beautiful; the colours were
intense, and the prevailing tint a dark blue; the sky and the calm
waters of the bay vied with each other in splendour. After passing
through some cultivated country, we entered a forest, which in the
grandeur of all its parts could not be exceeded.  We arrived by midday
at Ithacaia; this small village is situated on a plain, and round the
central house are the huts of the negroes.  These, from their regular
form and position, reminded me of the drawings of the Hottentot
habitations in Southern Africa.  As the moon rose early, we determined
to start the same evening for our sleeping-place at the Lagoa Marica.
As it was growing dark we passed under one of the massive, bare, and
steep hills of granite which are so common in this country.  This spot
is notorious from having been, for a long time, the residence of some
runaway slaves, who, by cultivating a little ground near the top,
contrived to eke out a subsistence.  At length they were discovered,
and a party of soldiers being sent, the whole were seized with the
exception of one old woman, who, sooner than again be led into slavery,
dashed herself to pieces from the summit of the mountain.  In a Roman
matron this would have been called the noble love of freedom: in a poor
negress it is mere brutal obstinacy.  We continued riding for some
hours.  For the few last miles the road was intricate, and it passed
through a desert waste of marshes and lagoons.  The scene by the dimmed
light of the moon was most desolate.  A few fireflies flitted by us;
and the solitary snipe, as it rose, uttered its plaintive cry.  The
distant and sullen roar of the sea scarcely broke the stillness of the
night.

April 9th.--We left our miserable sleeping-place before sunrise.  The
road passed through a narrow sandy plain, lying between the sea and the
interior salt lagoons.  The number of beautiful fishing birds, such as
egrets and cranes, and the succulent plants assuming most fantastical
forms, gave to the scene an interest which it would not otherwise have
possessed.  The few stunted trees were loaded with parasitical plants,
among which the beauty and delicious fragrance of some of the orchideae
were most to be admired. As the sun rose, the day became extremely hot,
and the reflection of the light and heat from the white sand was very
distressing.  We dined at Mandetiba; the thermometer in the shade being
84 degs.  The beautiful view of the distant wooded hills, reflected in
the perfectly calm water of an extensive lagoon, quite refreshed us. As
the venda [1] here was a very good one, and I have the pleasant, but
rare remembrance, of an excellent dinner, I will be grateful and
presently describe it, as the type of its class.  These houses are
often large, and are built of thick upright posts, with boughs
interwoven, and afterwards plastered.  They seldom have floors, and
never glazed windows; but are generally pretty well roofed. Universally
the front part is open, forming a kind of verandah, in which tables and
benches are placed.  The bed-rooms join on each side, and here the
passenger may sleep as comfortably as he can, on a wooden platform,
covered by a thin straw mat.  The venda stands in a courtyard, where
the horses are fed.  On first arriving it was our custom to unsaddle
the horses and give them their Indian corn; then, with a low bow, to
ask the senhor to do us the favour to give up something to eat.
"Anything you choose, sir," was his usual answer. For the few first
times, vainly I thanked providence for having guided us to so good a
man.  The conversation proceeding, the case universally became
deplorable.  "Any fish can you do us the favour of giving ?"--"Oh! no,
sir."--"Any soup?"--"No, sir."--"Any bread?"--"Oh! no, sir."--"Any
dried meat?"--"Oh! no, sir." If we were lucky, by waiting a couple of
hours, we obtained fowls, rice, and farinha.  It not unfrequently
happened, that we were obliged to kill, with stones, the poultry for
our own supper.  When, thoroughly exhausted by fatigue and hunger, we
timorously hinted that we should be glad of our meal, the pompous, and
(though true) most unsatisfactory answer was, "It will be ready when it
is ready." If we had dared to remonstrate any further, we should have
been told to proceed on our journey, as being too impertinent.  The
hosts are most ungracious and disagreeable in their manners; their
houses and their persons are often filthily dirty; the want of the
accommodation of forks, knives, and spoons is common; and I am sure no
cottage or hovel in England could be found in a state so utterly
destitute of every comfort.  At Campos Novos, however, we fared
sumptuously; having rice and fowls, biscuit, wine, and spirits, for
dinner; coffee in the evening, and fish with coffee for breakfast.  All
this, with good food for the horses, only cost 2s. 6d. per head.  Yet
the host of this venda, being asked if he knew anything of a whip which
one of the party had lost, gruffly answered, "How should I know? why
did you not take care of it?--I suppose the dogs have eaten it."

Leaving Mandetiba, we continued to pass through an intricate wilderness
of lakes; in some of which were fresh, in others salt water shells.  Of
the former kinds, I found a Limnaea in great numbers in a lake, into
which, the inhabitants assured me that the sea enters once a year, and
sometimes oftener, and makes the water quite salt.  I have no doubt
many interesting facts, in relation to marine and fresh water animals,
might be observed in this chain of lagoons, which skirt the coast of
Brazil.  M. Gay [2] has stated that he found in the neighbourhood of
Rio, shells of the marine genera solen and mytilus, and fresh water
ampullariae, living together in brackish water.  I also frequently
observed in the lagoon near the Botanic Garden, where the water is only
a little less salt than in the sea, a species of hydrophilus, very
similar to a water-beetle common in the ditches of England: in the same
lake the only shell belonged to a genus generally found in estuaries.

Leaving the coast for a time, we again entered the forest. The trees
were very lofty, and remarkable, compared with those of Europe, from
the whiteness of their trunks.  I see by my note-book, "wonderful and
beautiful, flowering parasites," invariably struck me as the most novel
object in these grand scenes.  Travelling onwards we passed through
tracts of pasturage, much injured by the enormous conical ants' nests,
which were nearly twelve feet high.  They gave to the plain exactly the
appearance of the mud volcanos at Jorullo, as figured by Humboldt.  We
arrived at Engenhodo after it was dark, having been ten hours on
horseback.  I never ceased, during the whole journey, to be surprised
at the amount of labour which the horses were capable of enduring; they
appeared also to recover from any injury much sooner than those of our
English breed.  The Vampire bat is often the cause of much trouble, by
biting the horses on their withers.  The injury is generally not so
much owing to the loss of blood, as to the inflammation which the
pressure of the saddle afterwards produces.  The whole circumstance has
lately been doubted in England; I was therefore fortunate in being
present when one (Desmodus d'orbignyi, Wat.) was actually caught on a
horse's back.  We were bivouacking late one evening near Coquimbo, in
Chile, when my servant, noticing that one of the horses was very
restive, went to see what was the matter, and fancying he could
distinguish something, suddenly put his hand on the beast's withers,
and secured the vampire.  In the morning the spot where the bite had
been inflicted was easily distinguished from being slightly swollen and
bloody.  The third day afterwards we rode the horse, without any ill
effects.

April 13th.--After three days' travelling we arrived at Socego, the
estate of Senhor Manuel Figuireda, a relation of one of our party.  The
house was simple, and, though like a barn in form, was well suited to
the climate.  In the sitting-room gilded chairs and sofas were oddly
contrasted with the whitewashed walls, thatched roof, and windows
without glass.  The house, together with the granaries, the stables,
and workshops for the blacks, who had been taught various trades,
formed a rude kind of quadrangle; in the centre of which a large pile
of coffee was drying.  These buildings stand on a little hill,
overlooking the cultivated ground, and surrounded on every side by a
wall of dark green luxuriant forest.  The chief produce of this part of
the country is coffee.  Each tree is supposed to yield annually, on an
average, two pounds; but some give as much as eight.  Mandioca or
cassada is likewise cultivated in great quantity.  Every part of this
plant is useful; the leaves and stalks are eaten by the horses, and the
roots are ground into a pulp, which, when pressed dry and baked, forms
the farinha, the principal article of sustenance in the Brazils.  It is
a curious, though well-known fact, that the juice of this most
nutritious plant is highly poisonous.  A few years ago a cow died at
this Fazenda, in consequence of having drunk some of it. Senhor
Figuireda told me that he had planted, the year before, one bag of
feijao or beans, and three of rice; the former of which produced
eighty, and the latter three hundred and twenty fold.  The pasturage
supports a fine stock of cattle, and the woods are so full of game that
a deer had been killed on each of the three previous days.  This
profusion of food showed itself at dinner, where, if the tables did not
groan, the guests surely did; for each person is expected to eat of
every dish.  One day, having, as I thought, nicely calculated so that
nothing should go away untasted, to my utter dismay a roast turkey and
a pig appeared in all their substantial reality.  During the meals, it
was the employment of a man to drive out of the room sundry old hounds,
and dozens of little black children, which crawled in together, at
every opportunity.  As long as the idea of slavery could be banished,
there was something exceedingly fascinating in this simple and
patriarchal style of living: it was such a perfect retirement and
independence from the rest of the world.

As soon as any stranger is seen arriving, a large bell is set tolling,
and generally some small cannon are fired.  The event is thus announced
to the rocks and woods, but to nothing else.  One morning I walked out
an hour before daylight to admire the solemn stillness of the scene; at
last, the silence was broken by the morning hymn, raised on high by the
whole body of the blacks; and in this manner their daily work is
generally begun.  On such fazendas as these, I have no doubt the slaves
pass happy and contented lives.  On Saturday and Sunday they work for
themselves, and in this fertile climate the labour of two days is
sufficient to support a man and his family for the whole week.

April 14th.--Leaving Socego, we rode to another estate on the Rio
Macae, which was the last patch of cultivated ground in that direction.
The estate was two and a half miles long, and the owner had forgotten
how many broad.  Only a very small piece had been cleared, yet almost
every acre was capable of yielding all the various rich productions of
a tropical land.  Considering the enormous area of Brazil, the
proportion of cultivated ground can scarcely be considered as anything,
compared to that which is left in the state of nature: at some future
age, how vast a population it will support!  During the second day's
journey we found the road so shut up, that it was necessary that a man
should go ahead with a sword to cut away the creepers.  The forest
abounded with beautiful objects; among which the tree ferns, though not
large, were, from their bright green foliage, and the elegant curvature
of their fronds, most worthy of admiration. In the evening it rained
very heavily, and although the thermometer stood at 65 degs., I felt
very cold.  As soon as the rain ceased, it was curious to observe the
extraordinary evaporation which commenced over the whole extent of the
forest.  At the height of a hundred feet the hills were buried in a
dense white vapour, which rose like columns of smoke from the most
thickly wooded parts, and especially from the valleys.  I observed this
phenomenon on several occasions. I suppose it is owing to the large
surface of foliage, previously heated by the sun's rays.

While staying at this estate, I was very nearly being an eye-witness to
one of those atrocious acts which can only take place in a slave
country.  Owing to a quarrel and a lawsuit, the owner was on the point
of taking all the women and children from the male slaves, and selling
them separately at the public auction at Rio.  Interest, and not any
feeling of compassion, prevented this act.  Indeed, I do not believe
the inhumanity of separating thirty families, who had lived together
for many years, even occurred to the owner.  Yet I will pledge myself,
that in humanity and good feeling he was superior to the common run of
men. It may be said there exists no limit to the blindness of interest
and selfish habit.  I may mention one very trifling anecdote, which at
the time struck me more forcibly than any story of cruelty.  I was
crossing a ferry with a negro, who was uncommonly stupid.  In
endeavouring to make him understand, I talked loud, and made signs, in
doing which I passed my hand near his face.  He, I suppose, thought I
was in a passion, and was going to strike him; for instantly, with a
frightened look and half-shut eyes, he dropped his hands.  I shall
never forget my feelings of surprise, disgust, and shame, at seeing a
great powerful man afraid even to ward off a blow, directed, as he
thought, at his face.  This man had been trained to a degradation lower
than the slavery of the most helpless animal.

April 18th.--In returning we spent two days at Socego, and I employed
them in collecting insects in the forest.  The greater number of trees,
although so lofty, are not more than three or four feet in
circumference.  There are, of course, a few of much greater dimensions.
Senhor Manuel was then making a canoe 70 feet in length from a solid
trunk, which had originally been 110 feet long, and of great thickness.
The contrast of palm trees, growing amidst the common branching kinds,
never fails to give the scene an intertropical character.  Here the
woods were ornamented by the Cabbage Palm--one of the most beautiful of
its family.  With a stem so narrow that it might be clasped with the
two hands, it waves its elegant head at the height of forty or fifty
feet above the ground.  The woody creepers, themselves covered by other
creepers, were of great thickness: some which I measured were two feet
in circumference.  Many of the older trees presented a very curious
appearance from the tresses of a liana hanging from their boughs, and
resembling bundles of hay.  If the eye was turned from the world of
foliage above, to the ground beneath, it was attracted by the extreme
elegance of the leaves of the ferns and mimosae. The latter, in some
parts, covered the surface with a brushwood only a few inches high.  In
walking across these thick beds of mimosae, a broad track was marked by
the change of shade, produced by the drooping of their sensitive
petioles. It is easy to specify the individual objects of admiration in
these grand scenes; but it is not possible to give an adequate idea of
the higher feelings of wonder, astonishment, and devotion, which fill
and elevate the mind.

April 19th.--Leaving Socego, during the two first days, we retraced our
steps.  It was very wearisome work, as the road generally ran across a
glaring hot sandy plain, not far from the coast.  I noticed that each
time the horse put its foot on the fine siliceous sand, a gentle
chirping noise was produced.  On the third day we took a different
line, and passed through the gay little village of Madre de Deos. This
is one of the principal lines of road in Brazil; yet it was in so bad a
state that no wheeled vehicle, excepting the clumsy bullock-wagon,
could pass along.  In our whole journey we did not cross a single
bridge built of stone; and those made of logs of wood were frequently
so much out of repair, that it was necessary to go on one side to avoid
them. All distances are inaccurately known.  The road is often marked
by crosses, in the place of milestones, to signify where human blood
has been spilled.  On the evening of the 23rd we arrived at Rio, having
finished our pleasant little excursion.

During the remainder of my stay at Rio, I resided in a cottage at
Botofogo Bay.  It was impossible to wish for anything more delightful
than thus to spend some weeks in so magnificent a country.  In England
any person fond of natural history enjoys in his walks a great
advantage, by always having something to attract his attention; but in
these fertile climates, teeming with life, the attractions are so
numerous, that he is scarcely able to walk at all.

The few observations which I was enabled to make were almost
exclusively confined to the invertebrate animals.  The existence of a
division of the genus Planaria, which inhabits the dry land, interested
me much.  These animals are of so simple a structure, that Cuvier has
arranged them with the intestinal worms, though never found within the
bodies of other animals.  Numerous species inhabit both salt and fresh
water; but those to which I allude were found, even in the drier parts
of the forest, beneath logs of rotten wood, on which I believe they
feed.  In general form they resemble little slugs, but are very much
narrower in proportion, and several of the species are beautifully
coloured with longitudinal stripes.  Their structure is very simple:
near the middle of the under or crawling surface there are two small
transverse slits, from the anterior one of which a funnel-shaped and
highly irritable mouth can be protruded.  For some time after the rest
of the animal was completely dead from the effects of salt water or any
other cause, this organ still retained its vitality.

I found no less than twelve different species of terrestrial Planariae
in different parts of the southern hemisphere. [3] Some specimens which
I obtained at Van Dieman's Land, I kept alive for nearly two months,
feeding them on rotten wood.  Having cut one of them transversely into
two nearly equal parts, in the course of a fortnight both had the shape
of perfect animals.  I had, however, so divided the body, that one of
the halves contained both the inferior orifices, and the other, in
consequence, none.  In the course of twenty-five days from the
operation, the more perfect half could not have been distinguished from
any other specimen.  The other had increased much in size; and towards
its posterior end, a clear space was formed in the parenchymatous mass,
in which a rudimentary cup-shaped mouth could clearly be distinguished;
on the under surface, however, no corresponding slit was yet open.  If
the increased heat of the weather, as we approached the equator, had
not destroyed all the individuals, there can be no doubt that this last
step would have completed its structure.  Although so well-known an
experiment, it was interesting to watch the gradual production of every
essential organ, out of the simple extremity of another animal.  It is
extremely difficult to preserve these Planariae; as soon as the
cessation of life allows the ordinary laws of change to act, their
entire bodies become soft and fluid, with a rapidity which I have never
seen equalled.

I first visited the forest in which these Planariae were found, in
company with an old Portuguese priest who took me out to hunt with him.
The sport consisted in turning into the cover a few dogs, and then
patiently waiting to fire at any animal which might appear.  We were
accompanied by the son of a neighbouring farmer--a good specimen of a
wild Brazilian youth.  He was dressed in a tattered old shirt and
trousers, and had his head uncovered: he carried an old-fashioned gun
and a large knife.  The habit of carrying the knife is universal; and
in traversing a thick wood it is almost necessary, on account of the
creeping plants. The frequent occurrence of murder may be partly
attributed to this habit.  The Brazilians are so dexterous with the
knife, that they can throw it to some distance with precision, and with
sufficient force to cause a fatal wound.  I have seen a number of
little boys practising this art as a game of play and from their skill
in hitting an upright stick, they promised well for more earnest
attempts.  My companion, the day before, had shot two large bearded
monkeys.  These animals have prehensile tails, the extremity of which,
even after death, can support the whole weight of the body.  One of
them thus remained fast to a branch, and it was necessary to cut down a
large tree to procure it.  This was soon effected, and down came tree
and monkey with an awful crash.  Our day's sport, besides the monkey,
was confined to sundry small green parrots and a few toucans.  I
profited, however, by my acquaintance with the Portuguese padre, for on
another occasion he gave me a fine specimen of the Yagouaroundi cat.

Every one has heard of the beauty of the scenery near Botofogo.  The
house in which I lived was seated close beneath the well-known mountain
of the Corcovado.  It has been remarked, with much truth, that abruptly
conical hills are characteristic of the formation which Humboldt
designates as gneiss-granite.  Nothing can be more striking than the
effect of these huge rounded masses of naked rock rising out of the
most luxuriant vegetation.

I was often interested by watching the clouds, which, rolling in from
seaward, formed a bank just beneath the highest point of the Corcovado.
This mountain, like most others, when thus partly veiled, appeared to
rise to a far prouder elevation than its real height of 2300 feet.  Mr.
Daniell has observed, in his meteorological essays, that a cloud
sometimes appears fixed on a mountain summit, while the wind continues
to blow over it.  The same phenomenon here presented a slightly
different appearance.  In this case the cloud was clearly seen to curl
over, and rapidly pass by the summit, and yet was neither diminished
nor increased in size.  The sun was setting, and a gentle southerly
breeze, striking against the southern side of the rock, mingled its
current with the colder air above; and the vapour was thus condensed;
but as the light wreaths of cloud passed over the ridge, and came
within the influence of the warmer atmosphere of the northern sloping
bank, they were immediately re-dissolved.

The climate, during the months of May and June, or the beginning of
winter, was delightful.  The mean temperature, from observations taken
at nine o'clock, both morning and evening, was only 72 degs.  It often
rained heavily, but the drying southerly winds soon again rendered the
walks pleasant.  One morning, in the course of six hours, 1.6 inches of
rain fell.  As this storm passed over the forests which surround the
Corcovado, the sound produced by the drops pattering on the countless
multitude of leaves was very remarkable, it could be heard at the
distance of a quarter of a mile, and was like the rushing of a great
body of water. After the hotter days, it was delicious to sit quietly
in the garden and watch the evening pass into night.  Nature, in these
climes, chooses her vocalists from more humble performers than in
Europe.  A small frog, of the genus Hyla, sits on a blade of grass
about an inch above the surface of the water, and sends forth a
pleasing chirp: when several are together they sing in harmony on
different notes.  I had some difficulty in catching a specimen of this
frog.  The genus Hyla has its toes terminated by small suckers; and I
found this animal could crawl up a pane of glass, when placed
absolutely perpendicular.  Various cicidae and crickets, at the same
time, keep up a ceaseless shrill cry, but which, softened by the
distance, is not unpleasant.  Every evening after dark this great
concert commenced; and often have I sat listening to it, until my
attention has been drawn away by some curious passing insect.

At these times the fireflies are seen flitting about from hedge to
hedge.  On a dark night the light can be seen at about two hundred
paces distant.  It is remarkable that in all the different kinds of
glowworms, shining elaters, and various marine animals (such as the
crustacea, medusae, nereidae, a coralline of the genus Clytia, and
Pyrosma), which I have observed, the light has been of a well-marked
green colour.  All the fireflies, which I caught here, belonged to the
Lampyridae (in which family the English glowworm is included), and the
greater number of specimens were of Lampyris occidentalis. [4] I found
that this insect emitted the most brilliant flashes when irritated: in
the intervals, the abdominal rings were obscured.  The flash was almost
co-instantaneous in the two rings, but it was just perceptible first in
the anterior one.  The shining matter was fluid and very adhesive:
little spots, where the skin had been torn, continued bright with a
slight scintillation, whilst the uninjured parts were obscured.  When
the insect was decapitated the rings remained uninterruptedly bright,
but not so brilliant as before: local irritation with a needle always
increased the vividness of the light.  The rings in one instance
retained their luminous property nearly twenty-four hours after the
death of the insect.  From these facts it would appear probable, that
the animal has only the power of concealing or extinguishing the light
for short intervals, and that at other times the display is
involuntary.  On the muddy and wet gravel-walks I found the larvae of
this lampyris in great numbers: they resembled in general form the
female of the English glowworm.  These larvae possessed but feeble
luminous powers; very differently from their parents, on the slightest
touch they feigned death and ceased to shine; nor did irritation excite
any fresh display.  I kept several of them alive for some time: their
tails are very singular organs, for they act, by a well-fitted
contrivance, as suckers or organs of attachment, and likewise as
reservoirs for saliva, or some such fluid.  I repeatedly fed them on
raw meat; and I invariably observed, that every now and then the
extremity of the tail was applied to the mouth, and a drop of fluid
exuded on the meat, which was then in the act of being consumed. The
tail, notwithstanding so much practice, does not seem to be able to
find its way to the mouth; at least the neck was always touched first,
and apparently as a guide.

When we were at Bahia, an elater or beetle (Pyrophorus luminosus,
Illig.) seemed the most common luminous insect. The light in this case
was also rendered more brilliant by irritation.  I amused myself one
day by observing the springing powers of this insect, which have not,
as it appears to me, been properly described. [5] The elater, when
placed on its back and preparing to spring, moved its head and thorax
backwards, so that the pectoral spine was drawn out, and rested on the
edge of its sheath.  The same backward movement being continued, the
spine, by the full action of the muscles, was bent like a spring; and
the insect at this moment rested on the extremity of its head and
wing-cases. The effort being suddenly relaxed, the head and thorax flew
up, and in consequence, the base of the wing-cases struck the
supporting surface with such force, that the insect by the reaction was
jerked upwards to the height of one or two inches.  The projecting
points of the thorax, and the sheath of the spine, served to steady the
whole body during the spring.  In the descriptions which I have read,
sufficient stress does not appear to have been laid on the elasticity
of the spine: so sudden a spring could not be the result of simple
muscular contraction, without the aid of some mechanical contrivance.

On several occasions I enjoyed some short but most pleasant excursions
in the neighbouring country.  One day I went to the Botanic Garden,
where many plants, well known for their great utility, might be seen
growing.  The leaves of the camphor, pepper, cinnamon, and clove trees
were delightfully aromatic; and the bread-fruit, the jaca, and the
mango, vied with each other in the magnificence of their foliage. The
landscape in the neighbourhood of Bahia almost takes its character from
the two latter trees.  Before seeing them, I had no idea that any trees
could cast so black a shade on the ground.  Both of them bear to the
evergreen vegetation of these climates the same kind of relation which
laurels and hollies in England do to the lighter green of the deciduous
trees.  It may be observed, that the houses within the tropics are
surrounded by the most beautiful forms of vegetation, because many of
them are at the same time most useful to man.  Who can doubt that these
qualities are united in the banana, the cocoa-nut, the many kinds of
palm, the orange, and the bread-fruit tree?

During this day I was particularly struck with a remark of Humboldt's,
who often alludes to "the thin vapour which, without changing the
transparency of the air, renders its tints more harmonious, and softens
its effects." This is an appearance which I have never observed in the
temperate zones.  The atmosphere, seen through a short space of half or
three-quarters of a mile, was perfectly lucid, but at a greater
distance all colours were blended into a most beautiful haze, of a pale
French grey, mingled with a little blue. The condition of the
atmosphere between the morning and about noon, when the effect was most
evident, had undergone little change, excepting in its dryness.  In the
interval, the difference between the dew point and temperature had
increased from 7.5 to 17 degs.

On another occasion I started early and walked to the Gavia, or topsail
mountain.  The air was delightfully cool and fragrant; and the drops of
dew still glittered on the leaves of the large liliaceous plants, which
shaded the streamlets of clear water.  Sitting down on a block of
granite, it was delightful to watch the various insects and birds as
they flew past.  The humming-bird seems particularly fond of such shady
retired spots.  Whenever I saw these little creatures buzzing round a
flower, with their wings vibrating so rapidly as to be scarcely
visible, I was reminded of the sphinx moths: their movements and habits
are indeed in many respects very similar.

Following a pathway, I entered a noble forest, and from a height of
five or six hundred feet, one of those splendid views was presented,
which are so common on every side of Rio.  At this elevation the
landscape attains its most brilliant tint; and every form, every shade,
so completely surpasses in magnificence all that the European has ever
beheld in his own country, that he knows not how to express his
feelings.  The general effect frequently recalled to my mind the gayest
scenery of the Opera-house or the great theatres.  I never returned
from these excursions empty-handed.  This day I found a specimen of a
curious fungus, called Hymenophallus.  Most people know the English
Phallus, which in autumn taints the air with its odious smell: this,
however, as the entomologist is aware, is, to some of our beetles a
delightful fragrance.  So was it here; for a Strongylus, attracted by
the odour, alighted on the fungus as I carried it in my hand.  We here
see in two distant countries a similar relation between plants and
insects of the same families, though the species of both are different.
When man is the agent in introducing into a country a new species, this
relation is often broken: as one instance of this I may mention, that
the leaves of the cabbages and lettuces, which in England afford food
to such a multitude of slugs and caterpillars, in the gardens near Rio
are untouched.

During our stay at Brazil I made a large collection of insects.  A few
general observations on the comparative importance of the different
orders may be interesting to the English entomologist.  The large and
brilliantly coloured Lepidoptera bespeak the zone they inhabit, far
more plainly than any other race of animals.  I allude only to the
butterflies; for the moths, contrary to what might have been expected
from the rankness of the vegetation, certainly appeared in much fewer
numbers than in our own temperate regions.  I was much surprised at the
habits of Papilio feronia.  This butterfly is not uncommon, and
generally frequents the orange-groves.  Although a high flier, yet it
very frequently alights on the trunks of trees.  On these occasions its
head is invariably placed downwards; and its wings are expanded in a
horizontal plane, instead of being folded vertically, as is commonly
the case.  This is the only butterfly which I have ever seen, that uses
its legs for running. Not being aware of this fact, the insect, more
than once, as I cautiously approached with my forceps, shuffled on one
side just as the instrument was on the point of closing, and thus
escaped.  But a far more singular fact is the power which this species
possesses of making a noise. [6] Several times when a pair, probably
male and female, were chasing each other in an irregular course, they
passed within a few yards of me; and I distinctly heard a clicking
noise, similar to that produced by a toothed wheel passing under a
spring catch.  The noise was continued at short intervals, and could be
distinguished at about twenty yards' distance: I am certain there is no
error in the observation.

I was disappointed in the general aspect of the Coleoptera. The number
of minute and obscurely coloured beetles is exceedingly great. [7] The
cabinets of Europe can, as yet, boast only of the larger species from
tropical climates.  It is sufficient to disturb the composure of an
entomologist's mind, to look forward to the future dimensions of a
complete catalogue.  The carnivorous beetles, or Carabidae, appear in
extremely few numbers within the tropics: this is the more remarkable
when compared to the case of the carnivorous quadrupeds, which are so
abundant in hot countries.  I was struck with this observation both on
entering Brazil, and when I saw the many elegant and active forms of
the Harpalidae re-appearing on the temperate plains of La Plata.  Do
the very numerous spiders and rapacious Hymenoptera supply the place of
the carnivorous beetles? The carrion-feeders and Brachelytra are very
uncommon; on the other hand, the Rhyncophora and Chrysomelidae, all of
which depend on the vegetable world for subsistence, are present in
astonishing numbers.  I do not here refer to the number of different
species, but to that of the individual insects; for on this it is that
the most striking character in the entomology of different countries
depends.  The orders Orthoptera and Hemiptera are particularly
numerous; as likewise is the stinging division of the Hymenoptera the
bees, perhaps, being excepted.  A person, on first entering a tropical
forest, is astonished at the labours of the ants: well-beaten paths
branch off in every direction, on which an army of never-failing
foragers may be seen, some going forth, and others returning, burdened
with pieces of green leaf, often larger than their own bodies.

A small dark-coloured ant sometimes migrates in countless numbers.  One
day, at Bahia, my attention was drawn by observing many spiders,
cockroaches, and other insects, and some lizards, rushing in the
greatest agitation across a bare piece of ground.  A little way behind,
every stalk and leaf was blackened by a small ant.  The swarm having
crossed the bare space, divided itself, and descended an old wall.  By
this means many insects were fairly enclosed; and the efforts which the
poor little creatures made to extricate themselves from such a death
were wonderful.  When the ants came to the road they changed their
course, and in narrow files reascended the wall.  Having placed a small
stone so as to intercept one of the lines, the whole body attacked it,
and then immediately retired.  Shortly afterwards another body came to
the charge, and again having failed to make any impression, this line
of march was entirely given up.  By going an inch round, the file might
have avoided the stone, and this doubtless would have happened, if it
had been originally there: but having been attacked, the lion-hearted
little warriors scorned the idea of yielding.

Certain wasp-like insects, which construct in the corners of the
verandahs clay cells for their larvae, are very numerous in the
neighbourhood of Rio.  These cells they stuff full of half-dead spiders
and caterpillars, which they seem wonderfully to know how to sting to
that degree as to leave them paralysed but alive, until their eggs are
hatched; and the larvae feed on the horrid mass of powerless,
half-killed victims--a sight which has been described by an
enthusiastic naturalist [8] as curious and pleasing!  I was much
interested one day by watching a deadly contest between a Pepsis and a
large spider of the genus Lycosa.  The wasp made a sudden dash at its
prey, and then flew away: the spider was evidently wounded, for, trying
to escape, it rolled down a little slope, but had still strength
sufficient to crawl into a thick tuft of grass.  The wasp soon
returned, and seemed surprised at not immediately finding its victim.
It then commenced as regular a hunt as ever hound did after fox; making
short semicircular casts, and all the time rapidly vibrating its wings
and antennae.  The spider, though well concealed, was soon discovered,
and the wasp, evidently still afraid of its adversary's jaws, after
much manoeuvring, inflicted two stings on the under side of its thorax.
At last, carefully examining with its antennae the now motionless
spider, it proceeded to drag away the body.  But I stopped both tyrant
and prey. [9]

The number of spiders, in proportion to other insects, is here compared
with England very much larger; perhaps more so than with any other
division of the articulate animals. The variety of species among the
jumping spiders appears almost infinite.  The genus, or rather family,
of Epeira, is here characterized by many singular forms; some species
have pointed coriaceous shells, others enlarged and spiny tibiae. Every
path in the forest is barricaded with the strong yellow web of a
species, belonging to the same division with the Epeira clavipes of
Fabricius, which was formerly said by Sloane to make, in the West
Indies, webs so strong as to catch birds.  A small and pretty kind of
spider, with very long fore-legs, and which appears to belong to an
undescribed genus, lives as a parasite on almost every one of these
webs.  I suppose it is too insignificant to be noticed by the great
Epeira, and is therefore allowed to prey on the minute insects, which,
adhering to the lines, would otherwise be wasted.  When frightened,
this little spider either feigns death by extending its front legs, or
suddenly drops from the web.  A large Epeira of the same division with
Epeira tuberculata and conica is extremely common, especially in dry
situations.  Its web, which is generally placed among the great leaves
of the common agave, is sometimes strengthened near the centre by a
pair or even four zigzag ribbons, which connect two adjoining rays.
When any large insect, as a grasshopper or wasp, is caught, the spider,
by a dexterous movement, makes it revolve very rapidly, and at the same
time emitting a band of threads from its spinners, soon envelops its
prey in a case like the cocoon of a silkworm. The spider now examines
the powerless victim, and gives the fatal bite on the hinder part of
its thorax; then retreating, patiently waits till the poison has taken
effect. The virulence of this poison may be judged of from the fact
that in half a minute I opened the mesh, and found a large wasp quite
lifeless.  This Epeira always stands with its head downwards near the
centre of the web.  When disturbed, it acts differently according to
circumstances: if there is a thicket below, it suddenly falls down; and
I have distinctly seen the thread from the spinners lengthened by the
animal while yet stationary, as preparatory to its fall.  If the ground
is clear beneath, the Epeira seldom falls, but moves quickly through a
central passage from one to the other side.  When still further
disturbed, it practises a most curious manoeuvre: standing in the
middle, it violently jerks the web, which it attached to elastic twigs,
till at last the whole acquires such a rapid vibratory movement, that
even the outline of the spider's body becomes indistinct.

It is well known that most of the British spiders, when a large insect
is caught in their webs, endeavour to cut the lines and liberate their
prey, to save their nets from being entirely spoiled.  I once, however,
saw in a hothouse in Shropshire a large female wasp caught in the
irregular web of a quite small spider; and this spider, instead of
cutting the web, most perseveringly continued to entangle the body, and
especially the wings, of its prey.  The wasp at first aimed in vain
repeated thrusts with its sting at its little antagonist. Pitying the
wasp, after allowing it to struggle for more than an hour, I killed it
and put it back into the web.  The spider soon returned; and an hour
afterwards I was much surprised to find it with its jaws buried in the
orifice, through which the sting is protruded by the living wasp.  I
drove the spider away two or three times, but for the next twenty-four
hours I always found it again sucking at the same place.  The spider
became much distended by the juices of its prey, which was many times
larger than itself.

I may here just mention, that I found, near St. Fe Bajada, many large
black spiders, with ruby-coloured marks on their backs, having
gregarious habits.  The webs were placed vertically, as is invariably
the case with the genus Epeira: they were separated from each other by
a space of about two feet, but were all attached to certain common
lines, which were of great length, and extended to all parts of the
community.  In this manner the tops of some large bushes were
encompassed by the united nets.  Azara [10] has described a gregarious
spider in Paraguay, which Walckanaer thinks must be a Theridion, but
probably it is an Epeira, and perhaps even the same species with mine.
I cannot, however, recollect seeing a central nest as large as a hat,
in which, during autumn, when the spiders die, Azara says the eggs are
deposited.  As all the spiders which I saw were of the same size, they
must have been nearly of the same age.  This gregarious habit, in so
typical a genus as Epeira, among insects, which are so bloodthirsty and
solitary that even the two sexes attack each other, is a very singular
fact.

In a lofty valley of the Cordillera, near Mendoza, I found another
spider with a singularly-formed web.  Strong lines radiated in a
vertical plane from a common centre, where the insect had its station;
but only two of the rays were connected by a symmetrical mesh-work; so
that the net, instead of being, as is generally the case, circular,
consisted of a wedge-shaped segment.  All the webs were similarly
constructed.

[1] Venda, the Portuguese name for an inn.

[2] Annales des Sciences Naturelles for 1833.

[3] I have described and named these species in the Annals of Nat.
Hist., vol. xiv. p. 241.

[4] I am greatly indebted to Mr. Waterhouse for his kindness in naming
for me this and many other insects, and giving me much valuable
assistance.

[5] Kirby's Entomology, vol. ii. p. 317.

[6] Mr. Doubleday has lately described (before the Entomological
Society, March 3rd, 1845) a peculiar structure in the wings of this
butterfly, which seems to be the means of its making its noise.  He
says, "It is remarkable for having a sort of drum at the base of the
fore wings, between the costal nervure and the subcostal.  These two
nervures, moreover, have a peculiar screw-like diaphragm or vessel in
the interior." I find in Langsdorff's travels (in the years 1803-7, p.
74) it is said, that in the island of St. Catherine's on the coast of
Brazil, a butterfly called Februa Hoffmanseggi, makes a noise, when
flying away, like a rattle.

[7] I may mention, as a common instance of one day's (June 23rd)
collecting, when I was not attending particularly to the Coleoptera,
that I caught sixty-eight species of that order. Among these, there
were only two of the Carabidae, four Brachelytra, fifteen Rhyncophora,
and fourteen of the Chrysomelidae.  Thirty-seven species of Arachnidae,
which I brought home, will be sufficient to prove that I was not paying
overmuch attention to the generally favoured order of Coleoptera.

[8] In a MS. in the British Museum by Mr. Abbott, who made his
observations in Georgia; see Mr. A. White's paper in the "Annals of
Nat. Hist.," vol. vii. p. 472. Lieut. Hutton has described a sphex with
similar habits in India, in the "Journal of the Asiatic Society," vol.
i. p. 555.

[9] Don Felix Azara (vol. i. p. 175), mentioning a hymenopterous
insect, probably of the same genus, says he saw it dragging a dead
spider through tall grass, in a straight line to its nest, which was
one hundred and sixty-three paces distant.  He adds that the wasp, in
order to find the road, every now and then made "demi-tours d'environ
trois palmes."

[10] Azara's Voyage, vol. i. p. 213



CHAPTER III

MALDONADO

Monte Video--Excursion to R. Polanco--Lazo and
Bolas--Partridges--Absence of Trees--Deer--Capybara, or River
Hog--Tucutuco--Molothrus, cuckoo-like
habits--Tyrant-flycatcher--Mocking-bird--Carrion Hawks--Tubes formed by
Lightning--House struck.


July 5th, 1832--In the morning we got under way, and stood out of the
splendid harbour of Rio de Janeiro.  In our passage to the Plata, we
saw nothing particular, excepting on one day a great shoal of
porpoises, many hundreds in number.  The whole sea was in places
furrowed by them; and a most extraordinary spectacle was presented, as
hundreds, proceeding together by jumps, in which their whole bodies
were exposed, thus cut the water.  When the ship was running nine knots
an hour, these animals could cross and recross the bows with the
greatest of ease, and then dash away right ahead.  As soon as we
entered the estuary of the Plata, the weather was very unsettled.  One
dark night we were surrounded by numerous seals and penguins, which
made such strange noises, that the officer on watch reported he could
hear the cattle bellowing on shore.  On a second night we witnessed a
splendid scene of natural fireworks; the mast-head and yard-arm-ends
shone with St. Elmo's light; and the form of the vane could almost be
traced, as if it had been rubbed with phosphorus.  The sea was so
highly luminous, that the tracks of the penguins were marked by a fiery
wake, and the darkness of the sky was momentarily illuminated by the
most vivid lightning.

When within the mouth of the river, I was interested by observing how
slowly the waters of the sea and river mixed. The latter, muddy and
discoloured, from its less specific gravity, floated on the surface of
the salt water.  This was curiously exhibited in the wake of the
vessel, where a line of blue water was seen mingling in little eddies,
with the adjoining fluid.

July 26th.--We anchored at Monte Video.  The Beagle was employed in
surveying the extreme southern and eastern coasts of America, south of
the Plata, during the two succeeding years.  To prevent useless
repetitions, I will extract those parts of my journal which refer to
the same districts without always attending to the order in which we
visited them.

MALDONADO is situated on the northern bank of the Plata, and not very
far from the mouth of the estuary.  It is a most quiet, forlorn, little
town; built, as is universally the case in these countries, with the
streets running at right angles to each other, and having in the middle
a large plaza or square, which, from its size, renders the scantiness
of the population more evident.  It possesses scarcely any trade; the
exports being confined to a few hides and living cattle. The
inhabitants are chiefly landowners, together with a few shopkeepers and
the necessary tradesmen, such as blacksmiths and carpenters, who do
nearly all the business for a circuit of fifty miles round.  The town
is separated from the river by a band of sand-hillocks, about a mile
broad: it is surrounded, on all other sides, by an open
slightly-undulating country, covered by one uniform layer of fine green
turf, on which countless herds of cattle, sheep, and horses graze.
There is very little land cultivated even close to the town. A few
hedges, made of cacti and agave, mark out where some wheat or Indian
corn has been planted.  The features of the country are very similar
along the whole northern bank of the Plata.  The only difference is,
that here the granitic hills are a little bolder.  The scenery is very
uninteresting; there is scarcely a house, an enclosed piece of ground,
or even a tree, to give it an air of cheerfulness Yet, after being
imprisoned for some time in a ship, there is a charm in the unconfined
feeling of walking over boundless plains of turf.  Moreover, if your
view is limited to a small space, many objects possess beauty.  Some of
the smaller birds are brilliantly coloured; and the bright green sward,
browsed short by the cattle, is ornamented by dwarf flowers, among
which a plant, looking like the daisy, claimed the place of an old
friend.  What would a florist say to whole tracts, so thickly covered
by the Verbena melindres, as, even at a distance, to appear of the most
gaudy scarlet?

I stayed ten weeks at Maldonado, in which time a nearly perfect
collection of the animals, birds, and reptiles, was procured.  Before
making any observations respecting them, I will give an account of a
little excursion I made as far as the river Polanco, which is about
seventy miles distant, in a northerly direction.  I may mention, as a
proof how cheap everything is in this country, that I paid only two
dollars a day, or eight shillings, for two men, together with a troop
of about a dozen riding-horses.  My companions were well armed with
pistols and sabres; a precaution which I thought rather unnecessary but
the first piece of news we heard was, that, the day before, a traveller
from Monte Video had been found dead on the road, with his throat cut.
This happened close to a cross, the record of a former murder.

On the first night we slept at a retired little country-house; and
there I soon found out that I possessed two or three articles,
especially a pocket compass, which created unbounded astonishment.  In
every house I was asked to show the compass, and by its aid, together
with a map, to point out the direction of various places.  It excited
the liveliest admiration that I, a perfect stranger, should know the
road (for direction and road are synonymous in this open country) to
places where I had never been.  At one house a young woman, who was ill
in bed, sent to entreat me to come and show her the compass.  If their
surprise was great, mine was greater, to find such ignorance among
people who possessed their thousands of cattle, and "estancias" of
great extent.  It can only be accounted for by the circumstance that
this retired part of the country is seldom visited by foreigners.  I
was asked whether the earth or sun moved; whether it was hotter or
colder to the north; where Spain was, and many other such questions.
The greater number of the inhabitants had an indistinct idea that
England, London, and North America, were different names for the same
place; but the better informed well knew that London and North America
were separate countries close together, and that England was a large
town in London!  I carried with me some promethean matches, which I
ignited by biting; it was thought so wonderful that a man should strike
fire with his teeth, that it was usual to collect the whole family to
see it: I was once offered a dollar for a single one.  Washing my face
in the morning caused much speculation at the village of Las Minas; a
superior tradesman closely cross-questioned me about so singular a
practice; and likewise why on board we wore our beards; for he had
heard from my guide that we did so.  He eyed me with much suspicion;
perhaps he had heard of ablutions in the Mahomedan religion, and
knowing me to be a heretick, probably he came to the conclusion that
all hereticks were Turks.  It is the general custom in this country to
ask for a night's lodging at the first convenient house.  The
astonishment at the compass, and my other feats of jugglery, was to a
certain degree advantageous, as with that, and the long stories my
guides told of my breaking stones, knowing venomous from harmless
snakes, collecting insects, etc., I repaid them for their hospitality.
I am writing as if I had been among the inhabitants of central Africa:
Banda Oriental would not be flattered by the comparison; but such were
my feelings at the time.

The next day we rode to the village of Las Minas.  The country was
rather more hilly, but otherwise continued the same; an inhabitant of
the Pampas no doubt would have considered it as truly Alpine.  The
country is so thinly inhabited, that during the whole day we scarcely
met a single person.  Las Minas is much smaller even than Maldonado. It
is seated on a little plain, and is surrounded by low rocky mountains.
It is of the usual symmetrical form, and with its whitewashed church
standing in the centre, had rather a pretty appearance.  The
outskirting houses rose out of the plain like isolated beings, without
the accompaniment of gardens or courtyards.  This is generally the case
in the country, and all the houses have, in consequence an
uncomfortable aspect.  At night we stopped at a pulperia, or
drinking-shop.  During the evening a great number of Gauchos came in to
drink spirits and smoke cigars: their appearance is very striking; they
are generally tall and handsome, but with a proud and dissolute
expression of countenance.  They frequently wear their moustaches and
long black hair curling down their backs.  With their brightly coloured
garments, great spurs clanking about their heels, and knives stuck as
daggers (and often so used) at their waists, they look a very different
race of men from what might be expected from their name of Gauchos, or
simple countrymen. Their politeness is excessive; they never drink
their spirits without expecting you to taste it; but whilst making
their exceedingly graceful bow, they seem quite as ready, if occasion
offered, to cut your throat.

On the third day we pursued rather an irregular course, as I was
employed in examining some beds of marble.  On the fine plains of turf
we saw many ostriches (Struthio rhea).  Some of the flocks contained as
many as twenty or thirty birds.  These, when standing on any little
eminence, and seen against the clear sky, presented a very noble
appearance.  I never met with such tame ostriches in any other part of
the country: it was easy to gallop up within a short distance of them;
but then, expanding their wings, they made all sail right before the
wind, and soon left the horse astern.

At night we came to the house of Don Juan Fuentes, a rich landed
proprietor, but not personally known to either of my companions.  On
approaching the house of a stranger, it is usual to follow several
little points of etiquette: riding up slowly to the door, the
salutation of Ave Maria is given, and until somebody comes out and asks
you to alight, it is not customary even to get off your horse: the
formal answer of the owner is, "sin pecado concebida"--that is,
conceived without sin.  Having entered the house, some general
conversation is kept up for a few minutes, till permission is asked to
pass the night there.  This is granted as a matter of course.  The
stranger then takes his meals with the family, and a room is assigned
him, where with the horsecloths belonging to his recado (or saddle of
the Pampas) he makes his bed.  It is curious how similar circumstances
produce such similar results in manners.  At the Cape of Good Hope the
same hospitality, and very nearly the same points of etiquette, are
universally observed.  The difference, however, between the character
of the Spaniard and that of the Dutch boer is shown, by the former
never asking his guest a single question beyond the strictest rule of
politeness, whilst the honest Dutchman demands where he has been, where
he is going, what is his business, and even how many brothers sisters,
or children he may happen to have.

Shortly after our arrival at Don Juan's, one of the largest herds of
cattle was driven in towards the house, and three beasts were picked
out to be slaughtered for the supply of the establishment.  These
half-wild cattle are very active; and knowing full well the fatal lazo,
they led the horses a long and laborious chase.  After witnessing the
rude wealth displayed in the number of cattle, men, and horses, Don
Juan's miserable house was quite curious.  The floor consisted of
hardened mud, and the windows were without glass; the sitting-room
boasted only of a few of the roughest chairs and stools, with a couple
of tables.  The supper, although several strangers were present,
consisted of two huge piles, one of roast beef, the other of boiled,
with some pieces of pumpkin: besides this latter there was no other
vegetable, and not even a morsel of bread.  For drinking, a large
earthenware jug of water served the whole party.  Yet this man was the
owner of several square miles of land, of which nearly every acre would
produce corn, and, with a little trouble, all the common vegetables.
The evening was spent in smoking, with a little impromptu singing,
accompanied by the guitar.  The signoritas all sat together in one
corner of the room, and did not sup with the men.

So many works have been written about these countries, that it is
almost superfluous to describe either the lazo or the bolas.  The lazo
consists of a very strong, but thin, well-plaited rope, made of raw
hide.  One end is attached to the broad surcingle, which fastens
together the complicated gear of the recado, or saddle used in the
Pampas; the other is terminated by a small ring of iron or brass, by
which a noose can be formed.  The Gaucho, when he is going to use the
lazo, keeps a small coil in his bridle-hand, and in the other holds the
running noose which is made very large, generally having a diameter of
about eight feet.  This he whirls round his head, and by the dexterous
movement of his wrist keeps the noose open; then, throwing it, he
causes it to fall on any particular spot he chooses.  The lazo, when
not used, is tied up in a small coil to the after part of the recado.
The bolas, or balls, are of two kinds: the simplest, which is chiefly
used for catching ostriches, consists of two round stones, covered with
leather, and united by a thin plaited thong, about eight feet long. The
other kind differs only in having three balls united by the thongs to a
common centre.  The Gaucho holds the smallest of the three in his hand,
and whirls the other two round and round his head; then, taking aim,
sends them like chain shot revolving through the air.  The balls no
sooner strike any object, than, winding round it, they cross each
other, and become firmly hitched.  The size and weight of the balls
vary, according to the purpose for which they are made: when of stone,
although not larger than an apple, they are sent with such force as
sometimes to break the leg even of a horse.  I have seen the balls made
of wood, and as large as a turnip, for the sake of catching these
animals without injuring them. The balls are sometimes made of iron,
and these can be hurled to the greatest distance.  The main difficulty
in using either lazo or bolas is to ride so well as to be able at full
speed, and while suddenly turning about, to whirl them so steadily
round the head, as to take aim: on foot any person would soon learn the
art.  One day, as I was amusing myself by galloping and whirling the
balls round my head, by accident the free one struck a bush, and its
revolving motion being thus destroyed, it immediately fell to the
ground, and, like magic, caught one hind leg of my horse; the other
ball was then jerked out of my hand, and the horse fairly secured.
Luckily he was an old practised animal, and knew what it meant;
otherwise he would probably have kicked till he had thrown himself
down.  The Gauchos roared with laughter; they cried out that they had
seen every sort of animal caught, but had never before seen a man
caught by himself.

During the two succeeding days, I reached the furthest point which I
was anxious to examine.  The country wore the same aspect, till at last
the fine green turf became more wearisome than a dusty turnpike road.
We everywhere saw great numbers of partridges (Nothura major).  These
birds do not go in coveys, nor do they conceal themselves like the
English kind.  It appears a very silly bird.  A man on horseback by
riding round and round in a circle, or rather in a spire, so as to
approach closer each time, may knock on the head as many as he pleases.
The more common method is to catch them with a running noose, or little
lazo, made of the stem of an ostrich's feather, fastened to the end of
a long stick.  A boy on a quiet old horse will frequently thus catch
thirty or forty in a day.  In Arctic North America [1] the Indians
catch the Varying Hare by walking spirally round and round it, when on
its form: the middle of the day is reckoned the best time, when the sun
is high, and the shadow of the hunter not very long.

On our return to Maldonado, we followed rather a different line of
road.  Near Pan de Azucar, a landmark well known to all those who have
sailed up the Plata, I stayed a day at the house of a most hospitable
old Spaniard.  Early in the morning we ascended the Sierra de las
Animas.  By the aid of the rising sun the scenery was almost
picturesque. To the westward the view extended over an immense level
plain as far as the Mount, at Monte Video, and to the eastward, over
the mammillated country of Maldonado.  On the summit of the mountain
there were several small heaps of stones, which evidently had lain
there for many years. My companion assured me that they were the work
of the Indians in the old time.  The heaps were similar, but on a much
smaller scale, to those so commonly found on the mountains of Wales.
The desire to signalize any event, on the highest point of the
neighbouring land, seems an universal passion with mankind.  At the
present day, not a single Indian, either civilized or wild, exists in
this part of the province; nor am I aware that the former inhabitants
have left behind them any more permanent records than these
insignificant piles on the summit of the Sierra de las Animas.


The general, and almost entire absence of trees in Banda Oriental is
remarkable.  Some of the rocky hills are partly covered by thickets,
and on the banks of the larger streams, especially to the north of Las
Minas, willow-trees are not uncommon.  Near the Arroyo Tapes I heard of
a wood of palms; and one of these trees, of considerable size, I saw
near the Pan de Azucar, in lat. 35 degs.  These, and the trees planted
by the Spaniards, offer the only exceptions to the general scarcity of
wood.  Among the introduced kinds may be enumerated poplars, olives,
peach, and other fruit trees: the peaches succeed so well, that they
afford the main supply of firewood to the city of Buenos Ayres.
Extremely level countries, such as the Pampas, seldom appear favourable
to the growth of trees.  This may possibly be attributed either to the
force of the winds, or the kind of drainage.  In the nature of the
land, however, around Maldonado, no such reason is apparent; the rocky
mountains afford protected situations; enjoying various kinds of soil;
streamlets of water are common at the bottoms of nearly every valley;
and the clayey nature of the earth seems adapted to retain moisture. It
has been inferred with much probability, that the presence of woodland
is generally determined [2] by the annual amount of moisture; yet in
this province abundant and heavy rain falls during the winter; and the
summer, though dry, is not so in any excessive degree. [3] We see
nearly the whole of Australia covered by lofty trees, yet that country
possesses a far more arid climate.  Hence we must look to some other
and unknown cause.

Confining our view to South America, we should certainly be tempted to
believe that trees flourished only under a very humid climate; for the
limit of the forest-land follows, in a most remarkable manner, that of
the damp winds.  In the southern part of the continent, where the
western gales, charged with moisture from the Pacific, prevail, every
island on the broken west coast, from lat. 38 degs. to the extreme
point of Tierra del Fuego, is densely covered by impenetrable forests.
On the eastern side of the Cordillera, over the same extent of
latitude, where a blue sky and a fine climate prove that the atmosphere
has been deprived of its moisture by passing over the mountains, the
arid plains of Patagonia support a most scanty vegetation.  In the more
northern parts of the continent, within the limits of the constant
south-eastern trade-wind, the eastern side is ornamented by magnificent
forests; whilst the western coast, from lat. 4 degs. S. to lat. 32
degs. S., may be described as a desert; on this western coast,
northward of lat. 4 degs. S., where the trade-wind loses its
regularity, and heavy torrents of rain fall periodically, the shores of
the Pacific, so utterly desert in Peru, assume near Cape Blanco the
character of luxuriance so celebrated at Guyaquil and Panama.  Hence in
the southern and northern parts of the continent, the forest and desert
lands occupy reversed positions with respect to the Cordillera, and
these positions are apparently determined by the direction of the
prevalent winds.  In the middle of the continent there is a broad
intermediate band, including central Chile and the provinces of La
Plata, where the rain-bringing winds have not to pass over lofty
mountains, and where the land is neither a desert nor covered by
forests.  But even the rule, if confined to South America, of trees
flourishing only in a climate rendered humid by rain-bearing winds, has
a strongly marked exception in the case of the Falkland Islands.  These
islands, situated in the same latitude with Tierra del Fuego and only
between two and three hundred miles distant from it, having a nearly
similar climate, with a geological formation almost identical, with
favourable situations and the same kind of peaty soil, yet can boast of
few plants deserving even the title of bushes; whilst in Tierra del
Fuego it is impossible to find an acre of land not covered by the
densest forest.  In this case, both the direction of the heavy gales of
wind and of the currents of the sea are favourable to the transport of
seeds from Tierra del Fuego, as is shown by the canoes and trunks of
trees drifted from that country, and frequently thrown on the shores of
the Western Falkland. Hence perhaps it is, that there are many plants
in common to the two countries but with respect to the trees of Tierra
del Fuego, even attempts made to transplant them have failed.

During our stay at Maldonado I collected several quadrupeds, eighty
kinds of birds, and many reptiles, including nine species of snakes. Of
the indigenous mammalia, the only one now left of any size, which is
common, is the Cervus campestris.  This deer is exceedingly abundant,
often in small herds, throughout the countries bordering the Plata and
in Northern Patagonia.  If a person crawling close along the ground,
slowly advances towards a herd, the deer frequently, out of curiosity,
approach to reconnoitre him.  I have by this means, killed from one
spot, three out of the same herd.  Although so tame and inquisitive,
yet when approached on horseback, they are exceedingly wary.  In this
country nobody goes on foot, and the deer knows man as its enemy only
when he is mounted and armed with the bolas. At Bahia Blanca, a recent
establishment in Northern Patagonia, I was surprised to find how little
the deer cared for the noise of a gun: one day I fired ten times from
within eighty yards at one animal; and it was much more startled at the
ball cutting up the ground than at the report of the rifle.  My powder
being exhausted, I was obliged to get up (to my shame as a sportsman be
it spoken, though well able to kill birds on the wing) and halloo till
the deer ran away.

The most curious fact with respect to this animal, is the
overpoweringly strong and offensive odour which proceeds from the buck.
It is quite indescribable: several times whilst skinning the specimen
which is now mounted at the Zoological Museum, I was almost overcome by
nausea.  I tied up the skin in a silk pocket-handkerchief, and so
carried it home: this handkerchief, after being well washed, I
continually used, and it was of course as repeatedly washed; yet every
time, for a space of one year and seven months, when first unfolded, I
distinctly perceived the odour.  This appears an astonishing instance
of the permanence of some matter, which nevertheless in its nature must
be most subtile and volatile.  Frequently, when passing at the distance
of half a mile to leeward of a herd, I have perceived the whole air
tainted with the effluvium.  I believe the smell from the buck is most
powerful at the period when its horns are perfect, or free from the
hairy skin.  When in this state the meat is, of course, quite
uneatable; but the Gauchos assert, that if buried for some time in
fresh earth, the taint is removed.  I have somewhere read that the
islanders in the north of Scotland treat the rank carcasses of the
fish-eating birds in the same manner.

The order Rodentia is here very numerous in species: of mice alone I
obtained no less than eight kinds. [4] The largest gnawing animal in
the world, the Hydrochaerus capybara (the water-hog), is here also
common.  One which I shot at Monte Video weighed ninety-eight pounds:
its length from the end of the snout to the stump-like tail, was three
feet two inches; and its girth three feet eight.  These great Rodents
occasionally frequent the islands in the mouth of the Plata, where the
water is quite salt, but are far more abundant on the borders of
fresh-water lakes and rivers. Near Maldonado three or four generally
live together.  In the daytime they either lie among the aquatic
plants, or openly feed on the turf plain. [5] When viewed at a
distance, from their manner of walking and colour they resemble pigs:
but when seated on their haunches, and attentively watching any object
with one eye, they reassume the appearance of their congeners, cavies
and rabbits.  Both the front and side view of their head has quite a
ludicrous aspect, from the great depth of their jaw.  These animals, at
Maldonado, were very tame; by cautiously walking, I approached within
three yards of four old ones.  This tameness may probably be accounted
for, by the Jaguar having been banished for some years, and by the
Gaucho not thinking it worth his while to hunt them.  As I approached
nearer and nearer they frequently made their peculiar noise, which is a
low abrupt grunt, not having much actual sound, but rather arising from
the sudden expulsion of air: the only noise I know at all like it, is
the first hoarse bark of a large dog.  Having watched the four from
almost within arm's length (and they me) for several minutes, they
rushed into the water at full gallop with the greatest impetuosity, and
emitted at the same time their bark.  After diving a short distance
they came again to the surface, but only just showed the upper part of
their heads.  When the female is swimming in the water, and has young
ones, they are said to sit on her back. These animals are easily killed
in numbers; but their skins are of trifling value, and the meat is very
indifferent.  On the islands in the Rio Parana they are exceedingly
abundant, and afford the ordinary prey to the Jaguar.

The Tucutuco (Ctenomys Brasiliensis) is a curious small animal, which
may be briefly described as a Gnawer, with the habits of a mole.  It is
extremely numerous in some parts of the country, but it is difficult to
be procured, and never, I believe, comes out of the ground.  It throws
up at the mouth of its burrows hillocks of earth like those of the
mole, but smaller.  Considerable tracts of country are so completely
undermined by these animals, that horses in passing over, sink above
their fetlocks.  The tucutucos appear, to a certain degree, to be
gregarious: the man who procured the specimens for me had caught six
together, and he said this was a common occurrence.  They are nocturnal
in their habits; and their principal food is the roots of plants, which
are the object of their extensive and superficial burrows. This animal
is universally known by a very peculiar noise which it makes when
beneath the ground.  A person, the first time he hears it, is much
surprised; for it is not easy to tell whence it comes, nor is it
possible to guess what kind of creature utters it.  The noise consists
in a short, but not rough, nasal grunt, which is monotonously repeated
about four times in quick succession: [6] the name Tucutuco is given in
imitation of the sound.  Where this animal is abundant, it may be heard
at all times of the day, and sometimes directly beneath one's feet.
When kept in a room, the tucutucos move both slowly and clumsily, which
appears owing to the outward action of their hind legs; and they are
quite incapable, from the socket of the thigh-bone not having a certain
ligament, of jumping even the smallest vertical height.  They are very
stupid in making any attempt to escape; when angry or frightened they
utter the tucutuco. Of those I kept alive several, even the first day,
became quite tame, not attempting to bite or to run away; others were a
little wilder.

The man who caught them asserted that very many are invariably found
blind.  A specimen which I preserved in spirits was in this state; Mr.
Reid considers it to be the effect of inflammation in the nictitating
membrane.  When the animal was alive I placed my finger within half an
inch of its head, and not the slightest notice was taken: it made its
way, however, about the room nearly as well as the others. Considering
the strictly subterranean habits of the tucutuco, the blindness, though
so common, cannot be a very serious evil; yet it appears strange that
any animal should possess an organ frequently subject to be injured.
Lamarck would have been delighted with this fact, had he known it, when
speculating [7] (probably with more truth than usual with him) on the
gradually _acquired_ blindness of the Asphalax, a Gnawer living under
ground, and of the Proteus, a reptile living in dark caverns filled
with water; in both of which animals the eye is in an almost
rudimentary state, and is covered by a tendinous membrane and skin.  In
the common mole the eye is extraordinarily small but perfect, though
many anatomists doubt whether it is connected with the true optic
nerve; its vision must certainly be imperfect, though probably useful
to the animal when it leaves its burrow.  In the tucutuco, which I
believe never comes to the surface of the ground, the eye is rather
larger, but often rendered blind and useless, though without apparently
causing any inconvenience to the animal; no doubt Lamarck would have
said that the tucutuco is now passing into the state of the Asphalax
and Proteus.

Birds of many kinds are extremely abundant on the undulating, grassy
plains around Maldonado.  There are several species of a family allied
in structure and manners to our Starling: one of these (Molothrus
niger) is remarkable from its habits.  Several may often be seen
standing together on the back of a cow or horse; and while perched on a
hedge, pluming themselves in the sun, they sometimes attempt to sing,
or rather to hiss; the noise being very peculiar, resembling that of
bubbles of air passing rapidly from a small orifice under water, so as
to produce an acute sound.  According to Azara, this bird, like the
cuckoo, deposits its eggs in other birds' nests.  I was several times
told by the country people that there certainly is some bird having
this habit; and my assistant in collecting, who is a very accurate
person, found a nest of the sparrow of this country (Zonotrichia
matutina), with one egg in it larger than the others, and of a
different colour and shape.  In North America there is another species
of Molothrus (M. pecoris), which has a similar cuckoo-like habit, and
which is most closely allied in every respect to the species from the
Plata, even in such trifling peculiarities as standing on the backs of
cattle; it differs only in being a little smaller, and in its plumage
and eggs being of a slightly different shade of colour.  This close
agreement in structure and habits, in representative species coming
from opposite quarters of a great continent, always strikes one as
interesting, though of common occurrence.

Mr. Swainson has well remarked, [8] that with the exception of the
Molothrus pecoris, to which must be added the M. niger, the cuckoos are
the only birds which can be called truly parasitical; namely, such as
"fasten themselves, as it were, on another living animal, whose animal
heat brings their young into life, whose food they live upon, and whose
death would cause theirs during the period of infancy." It is
remarkable that some of the species, but not all, both of the Cuckoo
and Molothrus, should agree in this one strange habit of their
parasitical propagation, whilst opposed to each other in almost every
other habit: the molothrus, like our starling, is eminently sociable,
and lives on the open plains without art or disguise: the cuckoo, as
every one knows, is a singularly shy bird; it frequents the most
retired thickets, and feeds on fruit and caterpillars.  In structure
also these two genera are widely removed from each other. Many
theories, even phrenological theories, have been advanced to explain
the origin of the cuckoo laying its eggs in other birds' nests.  M.
Prevost alone, I think, has thrown light by his observations [9] on
this puzzle: he finds that the female cuckoo, which, according to most
observers, lays at least from four to six eggs, must pair with the male
each time after laying only one or two eggs.  Now, if the cuckoo was
obliged to sit on her own eggs, she would either have to sit on all
together, and therefore leave those first laid so long, that they
probably would become addled; or she would have to hatch separately
each egg, or two eggs, as soon as laid: but as the cuckoo stays a
shorter time in this country than any other migratory bird, she
certainly would not have time enough for the successive hatchings.
Hence we can perceive in the fact of the cuckoo pairing several times,
and laying her eggs at intervals, the cause of her depositing her eggs
in other birds' nests, and leaving them to the care of foster-parents.
I am strongly inclined to believe that this view is correct, from
having been independently led (as we shall hereafter see) to an
analogous conclusion with regard to the South American ostrich, the
females of which are parasitical, if I may so express it, on each
other; each female laying several eggs in the nests of several other
females, and the male ostrich undertaking all the cares of incubation,
like the strange foster-parents with the cuckoo.

I will mention only two other birds, which are very common, and render
themselves prominent from their habits. The Saurophagus sulphuratus is
typical of the great American tribe of tyrant-flycatchers.  In its
structure it closely approaches the true shrikes, but in its habits may
be compared to many birds.  I have frequently observed it, hunting a
field, hovering over one spot like a hawk, and then proceeding on to
another.  When seen thus suspended in the air, it might very readily at
a short distance be mistaken for one of the Rapacious order; its stoop,
however, is very inferior in force and rapidity to that of a hawk.  At
other times the Saurophagus haunts the neighbourhood of water, and
there, like a kingfisher, remaining stationary, it catches any small
fish which may come near the margin.  These birds are not unfrequently
kept either in cages or in courtyards, with their wings cut.  They soon
become tame, and are very amusing from their cunning odd manners, which
were described to me as being similar to those of the common magpie.
Their flight is undulatory, for the weight of the head and bill appears
too great for the body.  In the evening the Saurophagus takes its stand
on a bush, often by the roadside, and continually repeats without a
change a shrill and rather agreeable cry, which somewhat resembles
articulate words: the Spaniards say it is like the words "Bien te veo"
(I see you well), and accordingly have given it this name.

A mocking-bird (Mimus orpheus), called by the inhabitants Calandria, is
remarkable, from possessing a song far superior to that of any other
bird in the country: indeed, it is nearly the only bird in South
America which I have observed to take its stand for the purpose of
singing.  The song may be compared to that of the Sedge warbler, but is
more powerful; some harsh notes and some very high ones, being mingled
with a pleasant warbling.  It is heard only during the spring.  At
other times its cry is harsh and far from harmonious.  Near Maldonado
these birds were tame and bold; they constantly attended the country
houses in numbers, to pick the meat which was hung up on the posts or
walls: if any other small bird joined the feast, the Calandria soon
chased it away.  On the wide uninhabited plains of Patagonia another
closely allied species, O. Patagonica of d'Orbigny, which frequents the
valleys clothed with spiny bushes, is a wilder bird, and has a slightly
different tone of voice.  It appears to me a curious circumstance, as
showing the fine shades of difference in habits, that judging from this
latter respect alone, when I first saw this second species, I thought
it was different from the Maldonado kind. Having afterwards procured a
specimen, and comparing the two without particular care, they appeared
so very similar, that I changed my opinion; but now Mr. Gould says that
they are certainly distinct; a conclusion in conformity with the
trifling difference of habit, of which, of course, he was not aware.

The number, tameness, and disgusting habits of the carrion-feeding
hawks of South America make them pre-eminently striking to any one
accustomed only to the birds of Northern Europe.  In this list may be
included four species of the Caracara or Polyborus, the Turkey buzzard,
the Gallinazo, and the Condor.  The Caracaras are, from their
structure, placed among the eagles: we shall soon see how ill they
become so high a rank.  In their habits they well supply the place of
our carrion-crows, magpies, and ravens; a tribe of birds widely
distributed over the rest of the world, but entirely absent in South
America.  To begin with the Polyborus Brasiliensis: this is a common
bird, and has a wide geographical range; it is most numerous on the
grassy savannahs of La Plata (where it goes by the name of Carrancha),
and is far from unfrequent throughout the sterile plains of Patagonia.
In the desert between the rivers Negro and Colorado, numbers constantly
attend the line of road to devour the carcasses of the exhausted
animals which chance to perish from fatigue and thirst.  Although thus
common in these dry and open countries, and likewise on the arid shores
of the Pacific, it is nevertheless found inhabiting the damp impervious
forests of West Patagonia and Tierra del Fuego. The Carranchas,
together with the Chimango, constantly attend in numbers the estancias
and slaughtering-houses.  If an animal dies on the plain the Gallinazo
commences the feast, and then the two species of Polyborus pick the
bones clean.  These birds, although thus commonly feeding together, are
far from being friends.  When the Carrancha is quietly seated on the
branch of a tree or on the ground, the Chimango often continues for a
long time flying backwards and forwards, up and down, in a semicircle,
trying each time at the bottom of the curve to strike its larger
relative.  The Carrancha takes little notice, except by bobbing its
head. Although the Carranchas frequently assemble in numbers, they are
not gregarious; for in desert places they may be seen solitary, or more
commonly by pairs.

The Carranchas are said to be very crafty, and to steal great numbers
of eggs.  They attempt, also, together with the Chimango, to pick off
the scabs from the sore backs of horses and mules.  The poor animal, on
the one hand, with its ears down and its back arched; and, on the
other, the hovering bird, eyeing at the distance of a yard the
disgusting morsel, form a picture, which has been described by Captain
Head with his own peculiar spirit and accuracy.  These false eagles
most rarely kill any living bird or animal; and their vulture-like,
necrophagous habits are very evident to any one who has fallen asleep
on the desolate plains of Patagonia, for when he wakes, he will see, on
each surrounding hillock, one of these birds patiently watching him
with an evil eye: it is a feature in the landscape of these countries,
which will be recognised by every one who has wandered over them.  If a
party of men go out hunting with dogs and horses, they will be
accompanied, during the day, by several of these attendants.  After
feeding, the uncovered craw protrudes; at such times, and indeed
generally, the Carrancha is an inactive, tame, and cowardly bird.  Its
flight is heavy and slow, like that of an English rook.  It seldom
soars; but I have twice seen one at a great height gliding through the
air with much ease.  It runs (in contradistinction to hopping), but not
quite so quickly as some of its congeners.  At times the Carrancha is
noisy, but is not generally so: its cry is loud, very harsh and
peculiar, and may be likened to the sound of the Spanish guttural g,
followed by a rough double r r; when uttering this cry it elevates its
head higher and higher, till at last, with its beak wide open, the
crown almost touches the lower part of the back.  This fact, which has
been doubted, is quite true; I have seen them several times with their
heads backwards in a completely inverted position.  To these
observations I may add, on the high authority of Azara, that the
Carrancha feeds on worms, shells, slugs, grasshoppers, and frogs; that
it destroys young lambs by tearing the umbilical cord; and that it
pursues the Gallinazo, till that bird is compelled to vomit up the
carrion it may have recently gorged.  Lastly, Azara states that several
Carranchas, five or six together, will unite in chase of large birds,
even such as herons.  All these facts show that it is a bird of very
versatile habits and considerable ingenuity.

The Polyborus Chimango is considerably smaller than the last species.
It is truly omnivorous, and will eat even bread; and I was assured that
it materially injures the potato crops in Chiloe, by stocking up the
roots when first planted.  Of all the carrion-feeders it is generally
the last which leaves the skeleton of a dead animal, and may often be
seen within the ribs of a cow or horse, like a bird in a cage.  Another
species is the Polyborus Novae Zelandiae, which is exceedingly common
in the Falkland Islands.  These birds in many respects resemble in
their habits the Carranchas.  They live on the flesh of dead animals
and on marine productions; and on the Ramirez rocks their whole
sustenance must depend on the sea.  They are extraordinarily tame and
fearless, and haunt the neighborhood of houses for offal.  If a hunting
party kills an animal, a number soon collect and patiently await,
standing on the ground on all sides.  After eating, their uncovered
craws are largely protruded, giving them a disgusting appearance.  They
readily attack wounded birds: a cormorant in this state having taken to
the shore, was immediately seized on by several, and its death hastened
by their blows.  The Beagle was at the Falklands only during the
summer, but the officers of the Adventure, who were there in the
winter, mention many extraordinary instances of the boldness and
rapacity of these birds.  They actually pounced on a dog that was lying
fast asleep close by one of the party; and the sportsmen had difficulty
in preventing the wounded geese from being seized before their eyes. It
is said that several together (in this respect resembling the
Carranchas) wait at the mouth of a rabbit-hole, and together seize on
the animal when it comes out.  They were constantly flying on board the
vessel when in the harbour; and it was necessary to keep a good look
out to prevent the leather being torn from the rigging, and the meat or
game from the stern.  These birds are very mischievous and inquisitive;
they will pick up almost anything from the ground; a large black glazed
hat was carried nearly a mile, as was a pair of the heavy balls used in
catching cattle.  Mr. Usborne experienced during the survey a more
severe loss, in their stealing a small Kater's compass in a red morocco
leather case, which was never recovered.  These birds are, moreover,
quarrelsome and very passionate; tearing up the grass with their bills
from rage.  They are not truly gregarious; they do not soar, and their
flight is heavy and clumsy; on the ground they run extremely fast, very
much like pheasants.  They are noisy, uttering several harsh cries, one
of which is like that of the English rook, hence the sealers always
call them rooks.  It is a curious circumstance that, when crying out,
they throw their heads upwards and backwards, after the same manner as
the Carrancha.  They build in the rocky cliffs of the sea-coast, but
only on the small adjoining islets, and not on the two main islands:
this is a singular precaution in so tame and fearless a bird.  The
sealers say that the flesh of these birds, when cooked, is quite white,
and very good eating; but bold must the man be who attempts such a meal.

We have now only to mention the turkey-buzzard (Vultur aura), and the
Gallinazo.  The former is found wherever the country is moderately
damp, from Cape Horn to North America.  Differently from the Polyborus
Brasiliensis and Chimango, it has found its way to the Falkland
Islands.  The turkey-buzzard is a solitary bird, or at most goes in
pairs.  It may at once be recognised from a long distance, by its
lofty, soaring, and most elegant flight.  It is well known to be a true
carrion-feeder.  On the west coast of Patagonia, among the
thickly-wooded islets and broken land, it lives exclusively on what the
sea throws up, and on the carcasses of dead seals.  Wherever these
animals are congregated on the rocks, there the vultures may be seen.
The Gallinazo (Cathartes atratus) has a different range from the last
species, as it never occurs southward of lat. 41 degs.  Azara states
that there exists a tradition that these birds, at the time of the
conquest, were not found near Monte Video, but that they subsequently
followed the inhabitants from more northern districts. At the present
day they are numerous in the valley of the Colorado, which is three
hundred miles due south of Monte Video.  It seems probable that this
additional migration has happened since the time of Azara.  The
Gallinazo generally prefers a humid climate, or rather the
neighbourhood of fresh water; hence it is extremely abundant in Brazil
and La Plata, while it is never found on the desert and arid plains of
Northern Patagonia, excepting near some stream. These birds frequent
the whole Pampas to the foot of the Cordillera, but I never saw or
heard of one in Chile; in Peru they are preserved as scavengers.  These
vultures certainly may be called gregarious, for they seem to have
pleasure in society, and are not solely brought together by the
attraction of a common prey.  On a fine day a flock may often be
observed at a great height, each bird wheeling round and round without
closing its wings, in the most graceful evolutions.  This is clearly
performed for the mere pleasure of the exercise, or perhaps is
connected with their matrimonial alliances.

I have now mentioned all the carrion-feeders, excepting the condor, an
account of which will be more appropriately introduced when we visit a
country more congenial to its habits than the plains of La Plata.


In a broad band of sand-hillocks which separate the Laguna del Potrero
from the shores of the Plata, at the distance of a few miles from
Maldonado, I found a group of those vitrified, siliceous tubes, which
are formed by lightning entering loose sand.  These tubes resemble in
every particular those from Drigg in Cumberland, described in the
Geological Transactions. [10] The sand-hillocks of Maldonado not being
protected by vegetation, are constantly changing their position.  From
this cause the tubes projected above the surface, and numerous
fragments lying near, showed that they had formerly been buried to a
greater depth.  Four sets entered the sand perpendicularly: by working
with my hands I traced one of them two feet deep; and some fragments
which evidently had belonged to the same tube, when added to the other
part, measured five feet three inches.  The diameter of the whole tube
was nearly equal, and therefore we must suppose that originally it
extended to a much greater depth.  These dimensions are however small,
compared to those of the tubes from Drigg, one of which was traced to a
depth of not less than thirty feet.

The internal surface is completely vitrified, glossy, and smooth.  A
small fragment examined under the microscope appeared, from the number
of minute entangled air or perhaps steam bubbles, like an assay fused
before the blowpipe. The sand is entirely, or in greater part,
siliceous; but some points are of a black colour, and from their glossy
surface possess a metallic lustre.  The thickness of the wall of the
tube varies from a thirtieth to a twentieth of an inch, and
occasionally even equals a tenth.  On the outside the grains of sand
are rounded, and have a slightly glazed appearance: I could not
distinguish any signs of crystallization.  In a similar manner to that
described in the Geological Transactions, the tubes are generally
compressed, and have deep longitudinal furrows, so as closely to
resemble a shrivelled vegetable stalk, or the bark of the elm or cork
tree.  Their circumference is about two inches, but in some fragments,
which are cylindrical and without any furrows, it is as much as four
inches.  The compression from the surrounding loose sand, acting while
the tube was still softened from the effects of the intense heat, has
evidently caused the creases or furrows.  Judging from the uncompressed
fragments, the measure or bore of the lightning (if such a term may be
used) must have been about one inch and a quarter.  At Paris, M.
Hachette and M. Beudant [11] succeeded in making tubes, in most
respects similar to these fulgurites, by passing very strong shocks of
galvanism through finely-powdered glass: when salt was added, so as to
increase its fusibility, the tubes were larger in every dimension. They
failed both with powdered felspar and quartz.  One tube, formed with
pounded glass, was very nearly an inch long, namely .982, and had an
internal diameter of .019 of an inch.  When we hear that the strongest
battery in Paris was used, and that its power on a substance of such
easy fusibility as glass was to form tubes so diminutive, we must feel
greatly astonished at the force of a shock of lightning, which,
striking the sand in several places, has formed cylinders, in one
instance of at least thirty feet long, and having an internal bore,
where not compressed, of full an inch and a half; and this in a
material so extraordinarily refractory as quartz!

The tubes, as I have already remarked, enter the sand nearly in a
vertical direction.  One, however, which was less regular than the
others, deviated from a right line, at the most considerable bend, to
the amount of thirty-three degrees. From this same tube, two small
branches, about a foot apart, were sent off; one pointed downwards, and
the other upwards.  This latter case is remarkable, as the electric
fluid must have turned back at the acute angle of 26 degs., to the line
of its main course.  Besides the four tubes which I found vertical, and
traced beneath the surface, there were several other groups of
fragments, the original sites of which without doubt were near.  All
occurred in a level area of shifting sand, sixty yards by twenty,
situated among some high sand-hillocks, and at the distance of about
half a mile from a chain of hills four or five hundred feet in height.
The most remarkable circumstance, as it appears to me, in this case as
well as in that of Drigg, and in one described by M. Ribbentrop in
Germany, is the number of tubes found within such limited spaces.  At
Drigg, within an area of fifteen yards, three were observed, and the
same number occurred in Germany.  In the case which I have described,
certainly more than four existed within the space of the sixty by
twenty yards.  As it does not appear probable that the tubes are
produced by successive distinct shocks, we must believe that the
lightning, shortly before entering the ground, divides itself into
separate branches.

The neighbourhood of the Rio Plata seems peculiarly subject to electric
phenomena.  In the year 1793, [12] one of the most destructive
thunderstorms perhaps on record happened at Buenos Ayres: thirty-seven
places within the city were struck by lightning, and nineteen people
killed.  From facts stated in several books of travels, I am inclined
to suspect that thunderstorms are very common near the mouths of great
rivers.  Is it not possible that the mixture of large bodies of fresh
and salt water may disturb the electrical equilibrium?  Even during our
occasional visits to this part of South America, we heard of a ship,
two churches, and a house having been struck.  Both the church and the
house I saw shortly afterwards: the house belonged to Mr. Hood, the
consul-general at Monte Video.  Some of the effects were curious: the
paper, for nearly a foot on each side of the line where the bell-wires
had run, was blackened.  The metal had been fused, and although the
room was about fifteen feet high, the globules, dropping on the chairs
and furniture, had drilled in them a chain of minute holes.  A part of
the wall was shattered, as if by gunpowder, and the fragments had been
blown off with force sufficient to dent the wall on the opposite side
of the room.  The frame of a looking-glass was blackened, and the
gilding must have been volatilized, for a smelling-bottle, which stood
on the chimney-piece, was coated with bright metallic particles, which
adhered as firmly as if they had been enamelled.

[1] Hearne's Journey, p. 383.

[2] Maclaren, art. "America," Encyclop. Brittann.

[3] Azara says, "Je crois que la quantite annuelle des pluies est, dans
toutes ces contrees, plus considerable qu'en Espagne."--Vol. i. p. 36.

[4] In South America I collected altogether twenty-seven species of
mice, and thirteen more are known from the works of Azara and other
authors.  Those collected by myself have been named and described by
Mr. Waterhouse at the meetings of the Zoological Society.  I must be
allowed to take this opportunity of returning my cordial thanks to Mr.
Waterhouse, and to the other gentleman attached to that Society, for
their kind and most liberal assistance on all occasions.

[5] In the stomach and duodenum of a capybara which I opened I found a
very large quantity of a thin yellowish fluid, in which scarcely a
fibre could be distinguished.  Mr. Owen informs me that a part of the
oesophagus is so constructed that nothing much larger than a crowquill
can be passed down. Certainly the broad teeth and strong jaws of this
animal are well fitted to grind into pulp the aquatic plants on which
it feeds.

[6] At the R. Negro, in Northern Patagonia, there is an animal of the
same habits, and probably a closely allied species, but which I never
saw.  Its noise is different from that of the Maldonado kind; it is
repeated only twice instead of three or four times, and is more
distinct and sonorous; when heard from a distance it so closely
resembles the sound made in cutting down a small tree with an axe, that
I have sometimes remained in doubt concerning it.

[7] Philosoph. Zoolog., tom. i. p. 242.

[8] Magazine of Zoology and Botany, vol. i. p. 217.

[9] Read before the Academy of Sciences in Paris. L'Institut, 1834, p.
418.

[10] Geolog. Transact. vol. ii. p. 528. In the Philosoph. Transact.
(1790, p. 294) Dr. Priestly has described some imperfect siliceous
tubes and a melted pebble of quartz, found in digging into the ground,
under a tree, where a man had been killed by lightning.

[11] Annals de Chimie et de Physique, tom. xxxvii. p. 319.

[12] Azara's Voyage, vol. i. p. 36.



CHAPTER IV

RIO NEGRO TO BAHIA BLANCA

Rio Negro--Estancias attacked by the
Indians--Salt-Lakes--Flamingoes--R. Negro to R. Colorado--Sacred
Tree--Patagonian Hare--Indian Families--General Rosas--Proceed to
Bahia Blanca--Sand Dunes--Negro Lieutenant--Bahia Blanca--Saline
Incrustations--Punta Alta--Zorillo.


JULY 24th, 1833.--The Beagle sailed from Maldonado, and on August the
3rd she arrived off the mouth of the Rio Negro.  This is the principal
river on the whole line of coast between the Strait of Magellan and the
Plata.  It enters the sea about three hundred miles south of the
estuary of the Plata.  About fifty years ago, under the old Spanish
government, a small colony was established here; and it is still the
most southern position (lat. 41 degs.) on this eastern coast of America
inhabited by civilized man.

The country near the mouth of the river is wretched in the extreme: on
the south side a long line of perpendicular cliffs commences, which
exposes a section of the geological nature of the country.  The strata
are of sandstone, and one layer was remarkable from being composed of a
firmly-cemented conglomerate of pumice pebbles, which must have
travelled more than four hundred miles, from the Andes. The surface is
everywhere covered up by a thick bed of gravel, which extends far and
wide over the open plain. Water is extremely scarce, and, where found,
is almost invariably brackish.  The vegetation is scanty; and although
there are bushes of many kinds, all are armed with formidable thorns,
which seem to warn the stranger not to enter on these inhospitable
regions.

The settlement is situated eighteen miles up the river. The road
follows the foot of the sloping cliff, which forms the northern
boundary of the great valley, in which the Rio Negro flows.  On the way
we passed the ruins of some fine "estancias," which a few years since
had been destroyed by the Indians.  They withstood several attacks.  A
man present at one gave me a very lively description of what took
place. The inhabitants had sufficient notice to drive all the cattle
and horses into the "corral" [1] which surrounded the house, and
likewise to mount some small cannon.  The Indians were Araucanians from
the south of Chile; several hundreds in number, and highly disciplined.
They first appeared in two bodies on a neighbouring hill; having there
dismounted, and taken off their fur mantles, they advanced naked to the
charge.  The only weapon of an Indian is a very long bamboo or chuzo,
ornamented with ostrich feathers, and pointed by a sharp spearhead.  My
informer seemed to remember with the greatest horror the quivering of
these chuzos as they approached near.  When close, the cacique
Pincheira hailed the besieged to give up their arms, or he would cut
all their throats.  As this would probably have been the result of
their entrance under any circumstances, the answer was given by a
volley of musketry.  The Indians, with great steadiness, came to the
very fence of the corral: but to their surprise they found the posts
fastened together by iron nails instead of leather thongs, and, of
course, in vain attempted to cut them with their knives.  This saved
the lives of the Christians: many of the wounded Indians were carried
away by their companions, and at last, one of the under caciques being
wounded, the bugle sounded a retreat.  They retired to their horses,
and seemed to hold a council of war.  This was an awful pause for the
Spaniards, as all their ammunition, with the exception of a few
cartridges, was expended.  In an instant the Indians mounted their
horses, and galloped out of sight.  Another attack was still more
quickly repulsed. A cool Frenchman managed the gun; he stopped till the
Indians approached close, and then raked their line with grape-shot: he
thus laid thirty-nine of them on the ground; and, of course, such a
blow immediately routed the whole party.

The town is indifferently called El Carmen or Patagones. It is built on
the face of a cliff which fronts the river, and many of the houses are
excavated even in the sandstone. The river is about two or three
hundred yards wide, and is deep and rapid.  The many islands, with
their willow-trees, and the flat headlands, seen one behind the other
on the northern boundary of the broad green valley, form, by the aid of
a bright sun, a view almost picturesque.  The number of inhabitants
does not exceed a few hundreds.  These Spanish colonies do not, like
our British ones, carry within themselves the elements of growth.  Many
Indians of pure blood reside here: the tribe of the Cacique Lucanee
constantly have their Toldos [2] on the outskirts of the town.  The
local government partly supplies them with provisions, by giving them
all the old worn-out horses, and they earn a little by making
horse-rugs and other articles of riding-gear.  These Indians are
considered civilized; but what their character may have gained by a
lesser degree of ferocity, is almost counterbalanced by their entire
immorality.  Some of the younger men are, however, improving; they are
willing to labour, and a short time since a party went on a
sealing-voyage, and behaved very well.  They were now enjoying the
fruits of their labour, by being dressed in very gay, clean clothes,
and by being very idle.  The taste they showed in their dress was
admirable; if you could have turned one of these young Indians into a
statue of bronze, his drapery would have been perfectly graceful.

One day I rode to a large salt-lake, or Salina, which is distant
fifteen miles from the town.  During the winter it consists of a
shallow lake of brine, which in summer is converted into a field of
snow-white salt.  The layer near the margin is from four to five inches
thick, but towards the centre its thickness increases.  This lake was
two and a half miles long, and one broad.  Others occur in the
neighbourhood many times larger, and with a floor of salt, two and
three feet in thickness, even when under water during the winter.  One
of these brilliantly white and level expanses in the midst of the brown
and desolate plain, offers an extraordinary spectacle.  A large
quantity of salt is annually drawn from the salina: and great piles,
some hundred tons in weight, were lying ready for exportation.  The
season for working the salinas forms the harvest of Patagones; for on
it the prosperity of the place depends.  Nearly the whole population
encamps on the bank of the river, and the people are employed in
drawing out the salt in bullock-waggons, This salt is crystallized in
great cubes, and is remarkably pure: Mr. Trenham Reeks has kindly
analyzed some for me, and he finds in it only 0.26 of gypsum and 0.22
of earthy matter.  It is a singular fact, that it does not serve so
well for preserving meat as sea-salt from the Cape de Verd islands; and
a merchant at Buenos Ayres told me that he considered it as fifty per
cent. less valuable.  Hence the Cape de Verd salt is constantly
imported, and is mixed with that from these salinas.  The purity of the
Patagonian salt, or absence from it of those other saline bodies found
in all sea-water, is the only assignable cause for this inferiority: a
conclusion which no one, I think, would have suspected, but which is
supported by the fact lately ascertained, [3] that those salts answer
best for preserving cheese which contain most of the deliquescent
chlorides.

The border of this lake is formed of mud: and in this numerous large
crystals of gypsum, some of which are three inches long, lie embedded;
whilst on the surface others of sulphate of soda lie scattered about.
The Gauchos call the former the "Padre del sal," and the latter the
"Madre;" they state that these progenitive salts always occur on the
borders of the salinas, when the water begins to evaporate. The mud is
black, and has a fetid odour.  I could not at first imagine the cause
of this, but I afterwards perceived that the froth which the wind
drifted on shore was coloured green, as if by confervae; I attempted to
carry home some of this green matter, but from an accident failed.
Parts of the lake seen from a short distance appeared of a reddish
colour, and this perhaps was owing to some infusorial animalcula.  The
mud in many places was thrown up by numbers of some kind of worm, or
annelidous animal.  How surprising it is that any creatures should be
able to exist in brine, and that they should be crawling among crystals
of sulphate of soda and lime!  And what becomes of these worms when,
during the long summer, the surface is hardened into a solid layer of
salt?  Flamingoes in considerable numbers inhabit this lake, and breed
here, throughout Patagonia, in Northern Chile, and at the Galapagos
Islands, I met with these birds wherever there were lakes of brine.  I
saw them here wading about in search of food--probably for the worms
which burrow in the mud; and these latter probably feed on infusoria or
confervae.  Thus we have a little living world within itself adapted to
these inland lakes of brine.  A minute crustaceous animal (Cancer
salinus) is said [4] to live in countless numbers in the brine-pans at
Lymington: but only in those in which the fluid has attained, from
evaporation, considerable strength--namely, about a quarter of a pound
of salt to a pint of water.  Well may we affirm that every part of the
world is habitable!  Whether lakes of brine, or those subterranean ones
hidden beneath volcanic mountains--warm mineral springs--the wide
expanse and depths of the ocean--the upper regions of the atmosphere,
and even the surface of perpetual snow--all support organic beings.


To the northward of the Rio Negro, between it and the inhabited country
near Buenos Ayres, the Spaniards have only one small settlement,
recently established at Bahia Blanca.  The distance in a straight line
to Buenos Ayres is very nearly five hundred British miles.  The
wandering tribes of horse Indians, which have always occupied the
greater part of this country, having of late much harassed the outlying
estancias, the government at Buenos Ayres equipped some time since an
army under the command of General Rosas for the purpose of
exterminating them.  The troops were now encamped on the banks of the
Colorado; a river lying about eighty miles northward of the Rio Negro.
When General Rosas left Buenos Ayres he struck in a direct line across
the unexplored plains: and as the country was thus pretty well cleared
of Indians, he left behind him, at wide intervals, a small party of
soldiers with a troop of horses (a posta), so as to be enabled to keep
up a communication with the capital.  As the Beagle intended to call at
Bahia Blanca, I determined to proceed there by land; and ultimately I
extended my plan to travel the whole way by the postas to Buenos Ayres.

August 11th.--Mr. Harris, an Englishman residing at Patagones, a guide,
and five Gauchos who were proceeding to the army on business, were my
companions on the journey. The Colorado, as I have already said, is
nearly eighty miles distant: and as we travelled slowly, we were two
days and a half on the road.  The whole line of country deserves
scarcely a better name than that of a desert.  Water is found only in
two small wells; it is called fresh; but even at this time of the year,
during the rainy season, it was quite brackish. In the summer this must
be a distressing passage; for now it was sufficiently desolate.  The
valley of the Rio Negro, broad as it is, has merely been excavated out
of the sandstone plain; for immediately above the bank on which the
town stands, a level country commences, which is interrupted only by a
few trifling valleys and depressions.  Everywhere the landscape wears
the same sterile aspect; a dry gravelly soil supports tufts of brown
withered grass, and low scattered bushes, armed with thorns.

Shortly after passing the first spring we came in sight of a famous
tree, which the Indians reverence as the altar of Walleechu.  It is
situated on a high part of the plain; and hence is a landmark visible
at a great distance.  As soon as a tribe of Indians come in sight of
it, they offer their adorations by loud shouts.  The tree itself is
low, much branched, and thorny: just above the root it has a diameter
of about three feet.  It stands by itself without any neighbour, and
was indeed the first tree we saw; afterwards we met with a few others
of the same kind, but they were far from common. Being winter the tree
had no leaves, but in their place numberless threads, by which the
various offerings, such as cigars, bread, meat, pieces of cloth, etc.,
had been suspended. Poor Indians, not having anything better, only pull
a thread out of their ponchos, and fasten it to the tree.  Richer
Indians are accustomed to pour spirits and mate into a certain hole,
and likewise to smoke upwards, thinking thus to afford all possible
gratification to Walleechu.  To complete the scene, the tree was
surrounded by the bleached bones of horses which had been slaughtered
as sacrifices.  All Indians of every age and sex make their offerings;
they then think that their horses will not tire, and that they
themselves shall be prosperous.  The Gaucho who told me this, said that
in the time of peace he had witnessed this scene, and that he and
others used to wait till the Indians had passed by, for the sake of
stealing from Walleechu the offerings.

The Gauchos think that the Indians consider the tree as the god itself,
but it seems for more probable that they regard it as the altar.  The
only cause which I can imagine for this choice, is its being a landmark
in a dangerous passage. The Sierra de la Ventana is visible at an
immense distance; and a Gaucho told me that he was once riding with an
Indian a few miles to the north of the Rio Colorado when the Indian
commenced making the same loud noise which is usual at the first sight
of the distant tree, putting his hand to his head, and then pointing in
the direction of the Sierra.  Upon being asked the reason of this, the
Indian said in broken Spanish, "First see the Sierra." About two
leagues beyond this curious tree we halted for the night: at this
instant an unfortunate cow was spied by the lynx-eyed Gauchos, who set
off in full chase, and in a few minutes dragged her in with their
lazos, and slaughtered her.  We here had the four necessaries of life
"en el campo,"--pasture for the horses, water (only a muddy puddle),
meat and firewood.  The Gauchos were in high spirits at finding all
these luxuries; and we soon set to work at the poor cow.  This was the
first night which I passed under the open sky, with the gear of the
recado for my bed.  There is high enjoyment in the independence of the
Gaucho life--to be able at any moment to pull up your horse, and say,
"Here we will pass the night." The death-like stillness of the plain,
the dogs keeping watch, the gipsy-group of Gauchos making their beds
round the fire, have left in my mind a strongly-marked picture of this
first night, which will never be forgotten.

The next day the country continued similar to that above described.  It
is inhabited by few birds or animals of any kind.  Occasionally a deer,
or a Guanaco (wild Llama) may be seen; but the Agouti (Cavia
Patagonica) is the commonest quadruped.  This animal here represents
our hares.  It differs, however, from that genus in many essential
respects; for instance, it has only three toes behind.  It is also
nearly twice the size, weighing from twenty to twenty-five pounds. The
Agouti is a true friend of the desert; it is a common feature of the
landscape to see two or three hopping quickly one after the other in a
straight line across these wild plains. They are found as far north as
the Sierra Tapalguen (lat. 37 degs. 30'), where the plain rather
suddenly becomes greener and more humid; and their southern limit is
between Port Desire and St. Julian, where there is no change in the
nature of the country.  It is a singular fact, that although the Agouti
is not now found as far south as Port St. Julian, yet that Captain
Wood, in his voyage in 1670, talks of them as being numerous there.
What cause can have altered, in a wide, uninhabited, and rarely-visited
country, the range of an animal like this?  It appears also, from the
number shot by Captain Wood in one day at Port Desire, that they must
have been considerably more abundant there formerly than at present.
Where the Bizcacha lives and makes its burrows, the Agouti uses them;
but where, as at Bahia Blanca, the Bizcacha is not found, the Agouti
burrows for itself.  The same thing occurs with the little owl of the
Pampas (Athene cunicularia), which has so often been described as
standing like a sentinel at the mouth of the burrows; for in Banda
Oriental, owing to the absence of the Bizcacha, it is obliged to hollow
out its own habitation.

The next morning, as we approached the Rio Colorado, the appearance of
the country changed; we soon came on a plain covered with turf, which,
from its flowers, tall clover, and little owls, resembled the Pampas.
We passed also a muddy swamp of considerable extent, which in summer
dries, and becomes incrusted with various salts; and hence is called a
salitral.  It was covered by low succulent plants, of the same kind
with those growing on the sea-shore.  The Colorado, at the pass where
we crossed it, is only about sixty yards wide; generally it must be
nearly double that width. Its course is very tortuous, being marked by
willow-trees and beds of reeds: in a direct line the distance to the
mouth of the river is said to be nine leagues, but by water
twenty-five.  We were delayed crossing in the canoe by some immense
troops of mares, which were swimming the river in order to follow a
division of troops into the interior.  A more ludicrous spectacle I
never beheld than the hundreds and hundreds of heads, all directed one
way, with pointed ears and distended snorting nostrils, appearing just
above the water like a great shoal of some amphibious animal. Mare's
flesh is the only food which the soldiers have when on an expedition.
This gives them a great facility of movement; for the distance to which
horses can be driven over these plains is quite surprising: I have been
assured that an unloaded horse can travel a hundred miles a day for
many days successively.

The encampment of General Rosas was close to the river. It consisted of
a square formed by waggons, artillery, straw huts, etc.  The soldiers
were nearly all cavalry; and I should think such a villainous,
banditti-like army was never before collected together.  The greater
number of men were of a mixed breed, between Negro, Indian, and
Spaniard.  I know not the reason, but men of such origin seldom have a
good expression of countenance.  I called on the Secretary to show my
passport.  He began to cross-question me in the most dignified and
mysterious manner.  By good luck I had a letter of recommendation from
the government of Buenos Ayres [5] to the commandant of Patagones. This
was taken to General Rosas, who sent me a very obliging message; and
the Secretary returned all smiles and graciousness.  We took up our
residence in the _rancho_, or hovel, of a curious old Spaniard, who had
served with Napoleon in the expedition against Russia.

We stayed two days at the Colorado; I had little to do, for the
surrounding country was a swamp, which in summer (December), when the
snow melts on the Cordillera, is over-flowed by the river.  My chief
amusement was watching the Indian families as they came to buy little
articles at the rancho where we stayed.  It was supposed that General
Rosas had about six hundred Indian allies.  The men were a tall, fine
race, yet it was afterwards easy to see in the Fuegian savage the same
countenance rendered hideous by cold, want of food, and less
civilization.  Some authors, in defining the primary races of mankind,
have separated these Indians into two classes; but this is certainly
incorrect.  Among the young women or chinas, some deserve to be called
even beautiful.  Their hair was coarse, but bright and black; and they
wore it in two plaits hanging down to the waist.  They had a high
colour, and eyes that glistened with brilliancy; their legs, feet, and
arms were small and elegantly formed; their ankles, and sometimes their
wrists, were ornamented by broad bracelets of blue beads.  Nothing
could be more interesting than some of the family groups.  A mother
with one or two daughters would often come to our rancho, mounted on
the same horse.  They ride like men, but with their knees tucked up
much higher. This habit, perhaps, arises from their being accustomed,
when travelling, to ride the loaded horses.  The duty of the women is
to load and unload the horses; to make the tents for the night; in
short to be, like the wives of all savages, useful slaves.  The men
fight, hunt, take care of the horses, and make the riding gear.  One of
their chief indoor occupations is to knock two stones together till
they become round, in order to make the bolas.  With this important
weapon the Indian catches his game, and also his horse, which roams
free over the plain.  In fighting, his first attempt is to throw down
the horse of his adversary with the bolas, and when entangled by the
fall to kill him with the chuzo.  If the balls only catch the neck or
body of an animal, they are often carried away and lost.  As the making
the stones round is the labour of two days, the manufacture of the
balls is a very common employment.  Several of the men and women had
their faces painted red, but I never saw the horizontal bands which are
so common among the Fuegians.  Their chief pride consists in having
everything made of silver; I have seen a cacique with his spurs,
stirrups, handle of his knife, and bridle made of this metal: the
head-stall and reins being of wire, were not thicker than whipcord; and
to see a fiery steed wheeling about under the command of so light a
chain, gave to the horsemanship a remarkable character of elegance.

General Rosas intimated a wish to see me; a circumstance which I was
afterwards very glad of.  He is a man of an extraordinary character,
and has a most predominant influence in the country, which it seems he
will use to its prosperity and advancement. [6] He is said to be the
owner of seventy-four square leagues of land, and to have about three
hundred thousand head of cattle.  His estates are admirably managed,
and are far more productive of corn than those of others.  He first
gained his celebrity by his laws for his own estancias, and by
disciplining several hundred men, so as to resist with success the
attacks of the Indians.  There are many stories current about the rigid
manner in which his laws were enforced.  One of these was, that no man,
on penalty of being put into the stocks, should carry his knife on a
Sunday: this being the principal day for gambling and drinking, many
quarrels arose, which from the general manner of fighting with the
knife often proved fatal.  One Sunday the Governor came in great form
to pay the estancia a visit, and General Rosas, in his hurry, walked
out to receive him with his knife, as usual, stuck in his belt.  The
steward touched his arm, and reminded him of the law; upon which
turning to the Governor, he said he was extremely sorry, but that he
must go into the stocks, and that till let out, he possessed no power
even in his own house.  After a little time the steward was persuaded
to open the stocks, and to let him out, but no sooner was this done,
than he turned to the steward and said, "You now have broken the laws,
so you must take my place in the stocks." Such actions as these
delighted the Gauchos, who all possess high notions of their own
equality and dignity.

General Rosas is also a perfect horseman--an accomplishment of no small
consequence In a country where an assembled army elected its general by
the following trial: A troop of unbroken horses being driven into a
corral, were let out through a gateway, above which was a cross-bar: it
was agreed whoever should drop from the bar on one of these wild
animals, as it rushed out, and should be able, without saddle or
bridle, not only to ride it, but also to bring it back to the door of
the corral, should be their general.  The person who succeeded was
accordingly elected; and doubtless made a fit general for such an army.
This extraordinary feat has also been performed by Rosas.

By these means, and by conforming to the dress and habits of the
Gauchos, he has obtained an unbounded popularity in the country, and in
consequence a despotic power.  I was assured by an English merchant,
that a man who had murdered another, when arrested and questioned
concerning his motive, answered, "He spoke disrespectfully of General
Rosas, so I killed him." At the end of a week the murderer was at
liberty.  This doubtless was the act of the general's party, and not of
the general himself.

In conversation he is enthusiastic, sensible, and very grave.  His
gravity is carried to a high pitch: I heard one of his mad buffoons
(for he keeps two, like the barons of old) relate the following
anecdote.  "I wanted very much to hear a certain piece of music, so I
went to the general two or three times to ask him; he said to me, 'Go
about your business, for I am engaged.' I went a second time; he said,
'If you come again I will punish you.' A third time I asked, and he
laughed.  I rushed out of the tent, but it was too late--he ordered two
soldiers to catch and stake me.  I begged by all the saints in heaven
he would let me off; but it would not do,--when the general laughs he
spares neither mad man nor sound." The poor flighty gentleman looked
quite dolorous, at the very recollection of the staking.  This is a
very severe punishment; four posts are driven into the ground, and the
man is extended by his arms and legs horizontally, and there left to
stretch for several hours. The idea is evidently taken from the usual
method of drying hides.  My interview passed away, without a smile, and
I obtained a passport and order for the government post-horses, and
this he gave me in the most obliging and ready manner.

In the morning we started for Bahia Blanca, which we reached in two
days.  Leaving the regular encampment, we passed by the toldos of the
Indians.  These are round like ovens, and covered with hides; by the
mouth of each, a tapering chuzo was stuck in the ground.  The toldos
were divided into separate groups, which belong to the different
caciques' tribes, and the groups were again divided into smaller ones,
according to the relationship of the owners.  For several miles we
travelled along the valley of the Colorado.  The alluvial plains on the
side appeared fertile, and it is supposed that they are well adapted to
the growth of corn.  Turning northward from the river, we soon entered
on a country, differing from the plains south of the river.  The land
still continued dry and sterile: but it supported many different kinds
of plants, and the grass, though brown and withered, was more abundant,
as the thorny bushes were less so.  These latter in a short space
entirely disappeared, and the plains were left without a thicket to
cover their nakedness.  This change in the vegetation marks the
commencement of the grand calcareo argillaceous deposit, which forms
the wide extent of the Pampas, and covers the granitic rocks of Banda
Oriental.  From the Strait of Magellan to the Colorado, a distance of
about eight hundred miles, the face of the country is everywhere
composed of shingle: the pebbles are chiefly of porphyry, and probably
owe their origin to the rocks of the Cordillera.  North of the Colorado
this bed thins out, and the pebbles become exceedingly small, and here
the characteristic vegetation of Patagonia ceases.

Having ridden about twenty-five miles, we came to a broad belt of
sand-dunes, which stretches, as far as the eye can reach, to the east
and west.  The sand-hillocks resting on the clay, allow small pools of
water to collect, and thus afford in this dry country an invaluable
supply of fresh water.  The great advantage arising from depressions
and elevations of the soil, is not often brought home to the mind. The
two miserable springs in the long passage between the Rio Negro and
Colorado were caused by trifling inequalities in the plain, without
them not a drop of water would have been found.  The belt of sand-dunes
is about eight miles wide; at some former period, it probably formed
the margin of a grand estuary, where the Colorado now flows.  In this
district, where absolute proofs of the recent elevation of the land
occur, such speculations can hardly be neglected by any one, although
merely considering the physical geography of the country.  Having
crossed the sandy tract, we arrived in the evening at one of the
post-houses; and, as the fresh horses were grazing at a distance we
determined to pass the night there.

The house was situated at the base of a ridge between one and two
hundred feet high--a most remarkable feature in this country.  This
posta was commanded by a negro lieutenant, born in Africa: to his
credit be it said, there was not a ranche between the Colorado and
Buenos Ayres in nearly such neat order as his.  He had a little room
for strangers, and a small corral for the horses, all made of sticks
and reeds; he had also dug a ditch round his house as a defence in case
of being attacked.  This would, however, have been of little avail, if
the Indians had come; but his chief comfort seemed to rest in the
thought of selling his life dearly.  A short time before, a body of
Indians had travelled past in the night; if they had been aware of the
posta, our black friend and his four soldiers would assuredly have been
slaughtered.  I did not anywhere meet a more civil and obliging man
than this negro; it was therefore the more painful to see that he would
not sit down and eat with us.

In the morning we sent for the horses very early, and started for
another exhilarating gallop.  We passed the Cabeza del Buey, an old
name given to the head of a large marsh, which extends from Bahia
Blanca.  Here we changed horses, and passed through some leagues of
swamps and saline marshes.  Changing horses for the last time, we again
began wading through the mud.  My animal fell and I was well soused in
black mire--a very disagreeable accident when one does not possess a
change of clothes.  Some miles from the fort we met a man, who told us
that a great gun had been fired, which is a signal that Indians are
near.  We immediately left the road, and followed the edge of a marsh,
which when chased offers the best mode of escape.  We were glad to
arrive within the walls, when we found all the alarm was about nothing,
for the Indians turned out to be friendly ones, who wished to join
General Rosas.

Bahia Blanca scarcely deserves the name of a village.  A few houses and
the barracks for the troops are enclosed by a deep ditch and fortified
wall.  The settlement is only of recent standing (since 1828); and its
growth has been one of trouble.  The government of Buenos Ayres
unjustly occupied it by force, instead of following the wise example of
the Spanish Viceroys, who purchased the land near the older settlement
of the Rio Negro, from the Indians.  Hence the need of the
fortifications; hence the few houses and little cultivated land without
the limits of the walls; even the cattle are not safe from the attacks
of the Indians beyond the boundaries of the plain, on which the
fortress stands.

The part of the harbour where the Beagle intended to anchor being
distant twenty-five miles, I obtained from the Commandant a guide and
horses, to take me to see whether she had arrived.  Leaving the plain
of green turf, which extended along the course of a little brook, we
soon entered on a wide level waste consisting either of sand, saline
marshes, or bare mud.  Some parts were clothed by low thickets, and
others with those succulent plants, which luxuriate only where salt
abounds.  Bad as the country was, ostriches, deer, agoutis, and
armadilloes, were abundant.  My guide told me, that two months before
he had a most narrow escape of his life: he was out hunting with two
other men, at no great distance from this part of the country, when
they were suddenly met by a party of Indians, who giving chase, soon
overtook and killed his two friends.  His own horse's legs were also
caught by the bolas, but he jumped off, and with his knife cut them
free: while doing this he was obliged to dodge round his horse, and
received two severe wounds from their chuzos.  Springing on the saddle,
he managed, by a most wonderful exertion, just to keep ahead of the
long spears of his pursuers, who followed him to within sight of the
fort.  From that time there was an order that no one should stray far
from the settlement.  I did not know of this when I started, and was
surprised to observe how earnestly my guide watched a deer, which
appeared to have been frightened from a distant quarter.

We found the Beagle had not arrived, and consequently set out on our
return, but the horses soon tiring, we were obliged to bivouac on the
plain.  In the morning we had caught an armadillo, which although a
most excellent dish when roasted in its shell, did not make a very
substantial breakfast and dinner for two hungry men.  The ground at the
place where we stopped for the night, was incrusted with a layer of
sulphate of soda, and hence, of course, was without water.  Yet many of
the smaller rodents managed to exist even here, and the tucutuco was
making its odd little grunt beneath my head, during half the night. Our
horses were very poor ones, and in the morning they were soon exhausted
from not having had anything to drink, so that we were obliged to walk.
About noon the dogs killed a kid, which we roasted. I ate some of it,
but it made me intolerably thirsty.  This was the more distressing as
the road, from some recent rain, was full of little puddles of clear
water, yet not a drop was drinkable.  I had scarcely been twenty hours
without water, and only part of the time under a hot sun, yet the
thirst rendered me very weak.  How people survive two or three days
under such circumstances, I cannot imagine: at the same time, I must
confess that my guide did not suffer at all, and was astonished that
one day's deprivation should be so troublesome to me.

I have several times alluded to the surface of the ground being
incrusted with salt.  This phenomenon is quite different from that of
the salinas, and more extraordinary. In many parts of South America,
wherever the climate is moderately dry, these incrustations occur; but
I have nowhere seen them so abundant as near Bahia Blanca.  The salt
here, and in other parts of Patagonia, consists chiefly of sulphate of
soda with some common salt.  As long as the ground remains moist in the
salitrales (as the Spaniards improperly call them, mistaking this
substance for saltpeter), nothing is to be seen but an extensive plain
composed of a black, muddy soil, supporting scattered tufts of
succulent plants.  On returning through one of these tracts, after a
week's hot weather, one is surprised to see square miles of the plain
white, as if from a slight fall of snow, here and there heaped up by
the wind into little drifts.  This latter appearance is chiefly caused
by the salts being drawn up, during the slow evaporation of the
moisture, round blades of dead grass, stumps of wood, and pieces of
broken earth, instead of being crystallized at the bottoms of the
puddles of water.  The salitrales occur either on level tracts elevated
only a few feet above the level of the sea, or on alluvial land
bordering rivers. M. Parchappe [7] found that the saline incrustation
on the plain, at the distance of some miles from the sea, consisted
chiefly of sulphate of soda, with only seven per cent. of common salt;
whilst nearer to the coast, the common salt increased to 37 parts in a
hundred.  This circumstance would tempt one to believe that the
sulphate of soda is generated in the soil, from the muriate, left on
the surface during the slow and recent elevation of this dry country.
The whole phenomenon is well worthy the attention of naturalists.  Have
the succulent, salt-loving plants, which are well known to contain much
soda, the power of decomposing the muriate? Does the black fetid mud,
abounding with organic matter, yield the sulphur and ultimately the
sulphuric acid?

Two days afterwards I again rode to the harbour: when not far from our
destination, my companion, the same man as before, spied three people
hunting on horseback.  He immediately dismounted, and watching them
intently, said, "They don't ride like Christians, and nobody can leave
the fort." The three hunters joined company, and likewise dismounted
from their horses.  At last one mounted again and rode over the hill
out of sight.  My companion said, "We must now get on our horses: load
your pistol;" and he looked to his own sword.  I asked, "Are they
Indians?"--"Quien sabe? (who knows?) if there are no more than three,
it does not signify." It then struck me, that the one man had gone over
the hill to fetch the rest of his tribe.  I suggested this; but all the
answer I could extort was, "Quien sabe?" His head and eye never for a
minute ceased scanning slowly the distant horizon.  I thought his
uncommon coolness too good a joke, and asked him why he did not return
home.  I was startled when he answered, "We are returning, but in a
line so as to pass near a swamp, into which we can gallop the horses as
far as they can go, and then trust to our own legs; so that there is no
danger." I did not feel quite so confident of this, and wanted to
increase our pace.  He said, "No, not until they do." When any little
inequality concealed us, we galloped; but when in sight, continued
walking.  At last we reached a valley, and turning to the left,
galloped quickly to the foot of a hill; he gave me his horse to hold,
made the dogs lie down, and then crawled on his hands and knees to
reconnoitre.  He remained in this position for some time, and at last,
bursting out in laughter, exclaimed, "Mugeres!" (women!).  He knew them
to be the wife and sister-in-law of the major's son, hunting for
ostrich's eggs.  I have described this man's conduct, because he acted
under the full impression that they were Indians. As soon, however, as
the absurd mistake was found out, he gave me a hundred reasons why they
could not have been Indians; but all these were forgotten at the time.
We then rode on in peace and quietness to a low point called Punta
Alta, whence we could see nearly the whole of the great harbour of
Bahia Blanca.

The wide expanse of water is choked up by numerous great mud-banks,
which the inhabitants call Cangrejales, or _crabberies_, from the
number of small crabs.  The mud is so soft that it is impossible to
walk over them, even for the shortest distance.  Many of the banks have
their surfaces covered with long rushes, the tops of which alone are
visible at high water.  On one occasion, when in a boat, we were so
entangled by these shallows that we could hardly find our way.  Nothing
was visible but the flat beds of mud; the day was not very clear, and
there was much refraction, or as the sailors expressed it, "things
loomed high." The only object within our view which was not level was
the horizon; rushes looked like bushes unsupported in the air, and
water like mud-banks, and mud-banks like water.

We passed the night in Punta Alta, and I employed myself in searching
for fossil bones; this point being a perfect catacomb for monsters of
extinct races.  The evening was perfectly calm and clear; the extreme
monotony of the view gave it an interest even in the midst of mud-banks
and gulls sand-hillocks and solitary vultures.  In riding back in the
morning we came across a very fresh track of a Puma, but did not
succeed in finding it.  We saw also a couple of Zorillos, or
skunks,--odious animals, which are far from uncommon.  In general
appearance, the Zorillo resembles a polecat, but it is rather larger,
and much thicker in proportion. Conscious of its power, it roams by day
about the open plain, and fears neither dog nor man.  If a dog is urged
to the attack, its courage is instantly checked by a few drops of the
fetid oil, which brings on violent sickness and running at the nose.
Whatever is once polluted by it, is for ever useless.  Azara says the
smell can be perceived at a league distant; more than once, when
entering the harbour of Monte Video, the wind being off shore, we have
perceived the odour on board the Beagle.  Certain it is, that every
animal most willingly makes room for the Zorillo.

[1] The corral is an enclosure made of tall and strong stakes.  Every
estancia, or farming estate, has one attached to it.

[2] The hovels of the Indians are thus called.

[3] Report of the Agricult. Chem. Assoc. in the Agricult. Gazette,
1845, p. 93.

[4] Linnaean Trans., vol. xi. p. 205. It is remarkable how all the
circumstances connected with the salt-lakes in Siberia and Patagonia
are similar.  Siberia, like Patagonia, appears to have been recently
elevated above the waters of the sea. In both countries the salt-lakes
occupy shallow depressions in the plains; in both the mud on the
borders is black and fetid; beneath the crust of common salt, sulphate
of soda or of magnesium occurs, imperfectly crystallized; and in both,
the muddy sand is mixed with lentils of gypsum.  The Siberian
salt-lakes are inhabited by small crustaceous animals; and flamingoes
(Edin. New Philos. Jour., Jan 1830) likewise frequent them.  As these
circumstances, apparently so trifling, occur in two distant continents,
we may feel sure that they are the necessary results of a common
cause--See Pallas's Travels, 1793 to 1794, pp. 129 - 134.

[5] I am bound to express in the strongest terms, my obligation to the
government of Buenos Ayres for the obliging manner in which passports
to all parts of the country were given me, as naturalist of the Beagle.

[6] This prophecy has turned out entirely and miserably wrong. 1845.

[7] Voyage dans l'Amerique Merid. par M. A. d'Orbigny. Part. Hist. tom.
i. p. 664.



CHAPTER V

BAHIA BLANCA

Bahia Blanca--Geology--Numerous gigantic Quadrupeds--Recent
Extinction--Longevity of species--Large Animals do not require a
luxuriant vegetation--Southern Africa--Siberian Fossils--Two Species of
Ostrich--Habits of Oven-bird--Armadilloes--Venomous Snake, Toad,
Lizard--Hybernation of Animal--Habits of Sea-Pen--Indian Wars and
Massacres--Arrow-head, antiquarian Relic.


The Beagle arrived here on the 24th of August, and a week afterwards
sailed for the Plata.  With Captain Fitz Roy's consent I was left
behind, to travel by land to Buenos Ayres.  I will here add some
observations, which were made during this visit and on a previous
occasion, when the Beagle was employed in surveying the harbour.

The plain, at the distance of a few miles from the coast, belongs to
the great Pampean formation, which consists in part of a reddish clay,
and in part of a highly calcareous marly rock.  Nearer the coast there
are some plains formed from the wreck of the upper plain, and from mud,
gravel, and sand thrown up by the sea during the slow elevation of the
land, of which elevation we have evidence in upraised beds of recent
shells, and in rounded pebbles of pumice scattered over the country. At
Punta Alta we have a section of one of these later-formed little
plains, which is highly interesting from the number and extraordinary
character of the remains of gigantic land-animals embedded in it. These
have been fully described by Professor Owen, in the Zoology of the
voyage of the Beagle, and are deposited in the College of Surgeons. I
will here give only a brief outline of their nature.

First, parts of three heads and other bones of the Megatherium, the
huge dimensions of which are expressed by its name.  Secondly, the
Megalonyx, a great allied animal. Thirdly, the Scelidotherium, also an
allied animal, of which I obtained a nearly perfect skeleton.  It must
have been as large as a rhinoceros: in the structure of its head it
comes according to Mr. Owen, nearest to the Cape Anteater, but in some
other respects it approaches to the armadilloes. Fourthly, the Mylodon
Darwinii, a closely related genus of little inferior size.  Fifthly,
another gigantic edental quadruped. Sixthly, a large animal, with an
osseous coat in compartments, very like that of an armadillo.
Seventhly, an extinct kind of horse, to which I shall have again to
refer. Eighthly, a tooth of a Pachydermatous animal, probably the same
with the Macrauchenia, a huge beast with a long neck like a camel,
which I shall also refer to again.  Lastly, the Toxodon, perhaps one of
the strangest animals ever discovered: in size it equalled an elephant
or megatherium, but the structure of its teeth, as Mr. Owen states,
proves indisputably that it was intimately related to the Gnawers, the
order which, at the present day, includes most of the smallest
quadrupeds: in many details it is allied to the Pachydermata: judging
from the position of its eyes, ears, and nostrils, it was probably
aquatic, like the Dugong and Manatee, to which it is also allied.  How
wonderfully are the different Orders, at the present time so well
separated, blended together in different points of the structure of the
Toxodon!

The remains of these nine great quadrupeds, and many detached bones,
were found embedded on the beach, within the space of about 200 yards
square.  It is a remarkable circumstance that so many different species
should be found together; and it proves how numerous in kind the
ancient inhabitants of this country must have been.  At the distance of
about thirty miles from Punta Alta, in a cliff of red earth, I found
several fragments of bones, some of large size. Among them were the
teeth of a gnawer, equalling in size and closely resembling those of
the Capybara, whose habits have been described; and therefore,
probably, an aquatic animal.  There was also part of the head of a
Ctenomys; the species being different from the Tucutuco, but with a
close general resemblance.  The red earth, like that of the Pampas, in
which these remains were embedded, contains, according to Professor
Ehrenberg, eight fresh-water and one salt-water infusorial animalcule;
therefore, probably, it was an estuary deposit.

The remains at Punta Alta were embedded in stratified gravel and
reddish mud, just such as the sea might now wash up on a shallow bank.
They were associated with twenty-three species of shells, of which
thirteen are recent and four others very closely related to recent
forms. [1] From the bones of the Scelidotherium, including even the
knee-cap, being intombed in their proper relative positions, and from
the osseous armour of the great armadillo-like animal being so well
preserved, together with the bones of one of its legs, we may feel
assured that these remains were fresh and united by their ligaments,
when deposited in the gravel together with the shells. [2] Hence we
have good evidence that the above enumerated gigantic quadrupeds, more
different from those of the present day than the oldest of the tertiary
quadrupeds of Europe, lived whilst the sea was peopled with most of its
present inhabitants; and we have confirmed that remarkable law so often
insisted on by Mr. Lyell, namely, that the "longevity of the species in
the mammalia is upon the whole inferior to that of the testacea." [3]

The great size of the bones of the Megatheroid animals, including the
Megatherium, Megalonyx, Scelidotherium, and Mylodon, is truly
wonderful.  The habits of life of these animals were a complete puzzle
to naturalists, until Professor Owen [4] solved the problem with
remarkable ingenuity.  The teeth indicate, by their simple structure,
that these Megatheroid animals lived on vegetable food, and probably on
the leaves and small twigs of trees; their ponderous forms and great
strong curved claws seem so little adapted for locomotion, that some
eminent naturalists have actually believed, that, like the sloths, to
which they are intimately related, they subsisted by climbing back
downwards on trees, and feeding on the leaves.  It was a bold, not to
say preposterous, idea to conceive even antediluvian trees, with
branches strong enough to bear animals as large as elephants. Professor
Owen, with far more probability, believes that, instead of climbing on
the trees, they pulled the branches down to them, and tore up the
smaller ones by the roots, and so fed on the leaves.  The colossal
breadth and weight of their hinder quarters, which can hardly be
imagined without having been seen, become on this view, of obvious
service, instead of being an incumbrance: their apparent clumsiness
disappears. With their great tails and their huge heels firmly fixed
like a tripod on the ground, they could freely exert the full force of
their most powerful arms and great claws.  Strongly rooted, indeed,
must that tree have been, which could have resisted such force!  The
Mylodon, moreover, was furnished with a long extensile tongue like that
of the giraffe, which, by one of those beautiful provisions of nature,
thus reaches with the aid of its long neck its leafy food.  I may
remark, that in Abyssinia the elephant, according to Bruce, when it
cannot reach with its proboscis the branches, deeply scores with its
tusks the trunk of the tree, up and down and all round, till it is
sufficiently weakened to be broken down.

The beds including the above fossil remains, stand only from fifteen to
twenty feet above the level of high-water; and hence the elevation of
the land has been small (without there has been an intercalated period
of subsidence, of which we have no evidence) since the great quadrupeds
wandered over the surrounding plains; and the external features of the
country must then have been very nearly the same as now.  What, it may
naturally be asked, was the character of the vegetation at that period;
was the country as wretchedly sterile as it now is?  As so many of the
co-embedded shells are the same with those now living in the bay, I was
at first inclined to think that the former vegetation was probably
similar to the existing one; but this would have been an erroneous
inference for some of these same shells live on the luxuriant coast of
Brazil; and generally, the character of the inhabitants of the sea are
useless as guides to judge of those on the land.  Nevertheless, from
the following considerations, I do not believe that the simple fact of
many gigantic quadrupeds having lived on the plains round Bahia Blanca,
is any sure guide that they formerly were clothed with a luxuriant
vegetation: I have no doubt that the sterile country a little
southward, near the Rio Negro, with its scattered thorny trees, would
support many and large quadrupeds.


That large animals require a luxuriant vegetation, has been a general
assumption which has passed from one work to another; but I do not
hesitate to say that it is completely false, and that it has vitiated
the reasoning of geologists on some points of great interest in the
ancient history of the world.  The prejudice has probably been derived
from India, and the Indian islands, where troops of elephants, noble
forests, and impenetrable jungles, are associated together in every
one's mind.  If, however, we refer to any work of travels through the
southern parts of Africa, we shall find allusions in almost every page
either to the desert character of the country, or to the numbers of
large animals inhabiting it.  The same thing is rendered evident by the
many engravings which have been published of various parts of the
interior.  When the Beagle was at Cape Town, I made an excursion of
some days' length into the country, which at least was sufficient to
render that which I had read more fully intelligible.

Dr. Andrew Smith, who, at the head of his adventurous party, has lately
succeeded in passing the Tropic of Capricorn, informs me that, taking
into consideration the whole of the southern part of Africa, there can
be no doubt of its being a sterile country.  On the southern and
south-eastern coasts there are some fine forests, but with these
exceptions, the traveller may pass for days together through open
plains, covered by a poor and scanty vegetation.  It is difficult to
convey any accurate idea of degrees of comparative fertility; but it
may be safely said that the amount of vegetation supported at any one
time [5] by Great Britain, exceeds, perhaps even tenfold, the quantity
on an equal area, in the interior parts of Southern Africa.  The fact
that bullock-waggons can travel in any direction, excepting near the
coast, without more than occasionally half an hour's delay in cutting
down bushes, gives, perhaps, a more definite notion of the scantiness
of the vegetation.  Now, if we look to the animals inhabiting these
wide plains, we shall find their numbers extraordinarily great, and
their bulk immense.  We must enumerate the elephant, three species of
rhinoceros, and probably, according to Dr. Smith, two others, the
hippopotamus, the giraffe, the bos caffer--as large as a full-grown
bull, and the elan--but little less, two zebras, and the quaccha, two
gnus, and several antelopes even larger than these latter animals.  It
may be supposed that although the species are numerous, the individuals
of each kind are few. By the kindness of Dr. Smith, I am enabled to
show that the case is very different.  He informs me, that in lat. 24
degs., in one day's march with the bullock-waggons, he saw, without
wandering to any great distance on either side, between one hundred and
one hundred and fifty rhinoceroses, which belonged to three species:
the same day he saw several herds of giraffes, amounting together to
nearly a hundred; and that although no elephant was observed, yet they
are found in this district.  At the distance of a little more than one
hour's march from their place of encampment on the previous night, his
party actually killed at one spot eight hippopotamuses, and saw many
more.  In this same river there were likewise crocodiles.  Of course it
was a case quite extraordinary, to see so many great animals crowded
together, but it evidently proves that they must exist in great
numbers. Dr. Smith describes the country passed through that day, as
"being thinly covered with grass, and bushes about four feet high, and
still more thinly with mimosa-trees." The waggons were not prevented
travelling in a nearly straight line.

Besides these large animals, every one the least acquainted with the
natural history of the Cape, has read of the herds of antelopes, which
can be compared only with the flocks of migratory birds.  The numbers
indeed of the lion, panther, and hyaena, and the multitude of birds of
prey, plainly speak of the abundance of the smaller quadrupeds: one
evening seven lions were counted at the same time prowling round Dr.
Smith's encampment.  As this able naturalist remarked to me, the
carnage each day in Southern Africa must indeed be terrific!  I confess
it is truly surprising how such a number of animals can find support in
a country producing so little food.  The larger quadrupeds no doubt
roam over wide tracts in search of it; and their food chiefly consists
of underwood, which probably contains much nutriment in a small bulk.
Dr. Smith also informs me that the vegetation has a rapid growth; no
sooner is a part consumed, than its place is supplied by a fresh stock.
There can be no doubt, however, that our ideas respecting the apparent
amount of food necessary for the support of large quadrupeds are much
exaggerated: it should have been remembered that the camel, an animal
of no mean bulk, has always been considered as the emblem of the desert.

The belief that where large quadrupeds exist, the vegetation must
necessarily be luxuriant, is the more remarkable, because the converse
is far from true.  Mr. Burchell observed to me that when entering
Brazil, nothing struck him more forcibly than the splendour of the
South American vegetation contrasted with that of South Africa,
together with the absence of all large quadrupeds.  In his Travels, [6]
he has suggested that the comparison of the respective weights (if
there were sufficient data) of an equal number of the largest
herbivorous quadrupeds of each country would be extremely curious.  If
we take on the one side, the elephant, [7] hippopotamus, giraffe, bos
caffer, elan, certainly three, and probably five species of rhinoceros;
and on the American side, two tapirs, the guanaco, three deer, the
vicuna, peccari, capybara (after which we must choose from the monkeys
to complete the number), and then place these two groups alongside each
other, it is not easy to conceive ranks more disproportionate in size.
After the above facts, we are compelled to conclude, against anterior
probability, [8] that among the mammalia there exists no close relation
between the bulk of the species, and the _quantity_ of the vegetation,
in the countries which they inhabit.

With regard to the number of large quadrupeds, there certainly exists
no quarter of the globe which will bear comparison with Southern
Africa.  After the different statements which have been given, the
extremely desert character of that region will not be disputed.  In the
European division of the world, we must look back to the tertiary
epochs, to find a condition of things among the mammalia, resembling
that now existing at the Cape of Good Hope.  Those tertiary epochs,
which we are apt to consider as abounding to an astonishing degree with
large animals, because we find the remains of many ages accumulated at
certain spots, could hardly boast of more large quadrupeds than
Southern Africa does at present.  If we speculate on the condition of
the vegetation during these epochs we are at least bound so far to
consider existing analogies, as not to urge as absolutely necessary a
luxuriant vegetation, when we see a state of things so totally
different at the Cape of Good Hope.

We know [9] that the extreme regions of North America, many degrees
beyond the limit where the ground at the depth of a few feet remains
perpetually congealed, are covered by forests of large and tall trees.
In a like manner, in Siberia, we have woods of birch, fir, aspen, and
larch, growing in a latitude [10] (64 degs.) where the mean temperature
of the air falls below the freezing point, and where the earth is so
completely frozen, that the carcass of an animal embedded in it is
perfectly preserved.  With these facts we must grant, as far as
_quantity alone_ of vegetation is concerned, that the great quadrupeds
of the later tertiary epochs might, in most parts of Northern Europe
and Asia, have lived on the spots where their remains are now found.  I
do not here speak of the kind of vegetation necessary for their
support; because, as there is evidence of physical changes, and as the
animals have become extinct, so may we suppose that the species of
plants have likewise been changed.

These remarks, I may be permitted to add, directly bear on the case of
the Siberian animals preserved in ice.  The firm conviction of the
necessity of a vegetation possessing a character of tropical
luxuriance, to support such large animals, and the impossibility of
reconciling this with the proximity of perpetual congelation, was one
chief cause of the several theories of sudden revolutions of climate,
and of overwhelming catastrophes, which were invented to account for
their entombment.  I am far from supposing that the climate has not
changed since the period when those animals lived, which now lie buried
in the ice.  At present I only wish to show, that as far as _quantity_
of food _alone_ is concerned, the ancient rhinoceroses might have
roamed over the _steppes_ of central Siberia (the northern parts
probably being under water) even in their present condition, as well as
the living rhinoceroses and elephants over the _Karros_ of Southern
Africa.


I will now give an account of the habits of some of the more
interesting birds which are common on the wild plains of Northern
Patagonia: and first for the largest, or South American ostrich.  The
ordinary habits of the ostrich are familiar to every one.  They live on
vegetable matter, such as roots and grass; but at Bahia Blanca I have
repeatedly seen three or four come down at low water to the extensive
mud-banks which are then dry, for the sake, as the Gauchos say, of
feeding on small fish.  Although the ostrich in its habits is so shy,
wary, and solitary, and although so fleet in its pace, it is caught
without much difficulty by the Indian or Gaucho armed with the bolas.
When several horsemen appear in a semicircle, it becomes confounded,
and does not know which way to escape.  They generally prefer running
against the wind; yet at the first start they expand their wings, and
like a vessel make all sail.  On one fine hot day I saw several
ostriches enter a bed of tall rushes, where they squatted concealed,
till quite closely approached. It is not generally known that ostriches
readily take to the water.  Mr. King informs me that at the Bay of San
Blas, and at Port Valdes in Patagonia, he saw these birds swimming
several times from island to island.  They ran into the water both when
driven down to a point, and likewise of their own accord when not
frightened: the distance crossed was about two hundred yards.  When
swimming, very little of their bodies appear above water; their necks
are extended a little forward, and their progress is slow. On two
occasions I saw some ostriches swimming across the Santa Cruz river,
where its course was about four hundred yards wide, and the stream
rapid.  Captain Sturt, [11] when descending the Murrumbidgee, in
Australia, saw two emus in the act of swimming.

The inhabitants of the country readily distinguish, even at a distance,
the cock bird from the hen.  The former is larger and darker-coloured,
[12] and has a bigger head.  The ostrich, I believe the cock, emits a
singular, deep-toned, hissing note: when first I heard it, standing in
the midst of some sand-hillocks, I thought it was made by some wild
beast, for it is a sound that one cannot tell whence it comes, or from
how far distant.  When we were at Bahia Blanca in the months of
September and October, the eggs, in extraordinary numbers, were found
all over the country.  They lie either scattered and single, in which
case they are never hatched, and are called by the Spaniards huachos;
or they are collected together into a shallow excavation, which forms
the nest.  Out of the four nests which I saw, three contained
twenty-two eggs each, and the fourth twenty-seven. In one day's hunting
on horseback sixty-four eggs were found; forty-four of these were in
two nests, and the remaining twenty, scattered huachos.  The Gauchos
unanimously affirm, and there is no reason to doubt their statement,
that the male bird alone hatches the eggs, and for some time afterwards
accompanies the young.  The cock when on the nest lies very close; I
have myself almost ridden over one.  It is asserted that at such times
they are occasionally fierce, and even dangerous, and that they have
been known to attack a man on horseback, trying to kick and leap on
him.  My informer pointed out to me an old man, whom he had seen much
terrified by one chasing him.  I observe in Burchell's travels in South
Africa, that he remarks, "Having killed a male ostrich, and the
feathers being dirty, it was said by the Hottentots to be a nest bird."
I understand that the male emu in the Zoological Gardens takes charge
of the nest: this habit, therefore, is common to the family.

The Gauchos unanimously affirm that several females lay in one nest.  I
have been positively told that four or five hen birds have been watched
to go in the middle of the day, one after the other, to the same nest.
I may add, also, that it is believed in Africa, that two or more
females lay in one nest. [13] Although this habit at first appears very
strange, I think the cause may be explained in a simple manner.  The
number of eggs in the nest varies from twenty to forty, and even to
fifty; and according to Azara, some times to seventy or eighty.  Now,
although it is most probable, from the number of eggs found in one
district being so extraordinarily great in proportion to the parent
birds, and likewise from the state of the ovarium of the hen, that she
may in the course of the season lay a large number, yet the time
required must be very long.  Azara states, [14] that a female in a
state of domestication laid seventeen eggs, each at the interval of
three days one from another.  If the hen was obliged to hatch her own
eggs, before the last was laid the first probably would be addled; but
if each laid a few eggs at successive periods, in different nests, and
several hens, as is stated to be the case, combined together, then the
eggs in one collection would be nearly of the same age. If the number
of eggs in one of these nests is, as I believe, not greater on an
average than the number laid by one female in the season, then there
must be as many nests as females, and each cock bird will have its fair
share of the labour of incubation; and that during a period when the
females probably could not sit, from not having finished laying. [15] I
have before mentioned the great numbers of huachos, or deserted eggs;
so that in one day's hunting twenty were found in this state.  It
appears odd that so many should be wasted.  Does it not arise from the
difficulty of several females associating together, and finding a male
ready to undertake the office of incubation?  It is evident that there
must at first be some degree of association between at least two
females; otherwise the eggs would remain scattered over the wide plain,
at distances far too great to allow of the male collecting them into
one nest: some authors have believed that the scattered eggs were
deposited for the young birds to feed on.  This can hardly be the case
in America, because the huachos, although often found addled and
putrid, are generally whole.

When at the Rio Negro in Northern Patagonia, I repeatedly heard the
Gauchos talking of a very rare bird which they called Avestruz Petise.
They described it as being less than the common ostrich (which is there
abundant), but with a very close general resemblance.  They said its
colour was dark and mottled, and that its legs were shorter, and
feathered lower down than those of the common ostrich. It is more
easily caught by the bolas than the other species. The few inhabitants
who had seen both kinds, affirmed they could distinguish them apart
from a long distance.  The eggs of the small species appeared, however,
more generally known; and it was remarked, with surprise, that they
were very little less than those of the Rhea, but of a slightly
different form, and with a tinge of pale blue.  This species occurs
most rarely on the plains bordering the Rio Negro; but about a degree
and a half further south they are tolerably abundant. When at Port
Desire, in Patagonia (lat. 48 degs.), Mr. Martens shot an ostrich; and
I looked at it, forgetting at the moment, in the most unaccountable
manner, the whole subject of the Petises, and thought it was a not
full-grown bird of the common sort.  It was cooked and eaten before my
memory returned.  Fortunately the head, neck, legs, wings, many of the
larger feathers, and a large part of the skin, had been preserved; and
from these a very nearly perfect specimen has been put together, and is
now exhibited in the museum of the Zoological Society.  Mr. Gould, in
describing this new species, has done me the honour of calling it after
my name.

Among the Patagonian Indians in the Strait of Magellan, we found a half
Indian, who had lived some years with the tribe, but had been born in
the northern provinces.  I asked him if he had ever heard of the
Avestruz Petise?  He answered by saying, "Why, there are none others in
these southern countries." He informed me that the number of eggs in
the nest of the petise is considerably less than in that of the other
kind, namely, not more than fifteen on an average, but he asserted that
more than one female deposited them.  At Santa Cruz we saw several of
these birds.  They were excessively wary: I think they could see a
person approaching when too far off to be distinguished themselves. In
ascending the river few were seen; but in our quiet and rapid descent,
many, in pairs and by fours or fives, were observed.  It was remarked
that this bird did not expand its wings, when first starting at full
speed, after the manner of the northern kind.  In conclusion I may
observe, that the Struthio rhea inhabits the country of La Plata as far
as a little south of the Rio Negro in lat. 41 degs., and that the
Struthio Darwinii takes its place in Southern Patagonia; the part about
the Rio Negro being neutral territory.  M. A. d'Orbigny, [16] when at
the Rio Negro, made great exertions to procure this bird, but never had
the good fortune to succeed.  Dobrizhoffer [17] long ago was aware of
there being two kinds of ostriches, he says, "You must know, moreover,
that Emus differ in size and habits in different tracts of land; for
those that inhabit the plains of Buenos Ayres and Tucuman are larger,
and have black, white and grey feathers; those near to the Strait of
Magellan are smaller and more beautiful, for their white feathers are
tipped with black at the extremity, and their black ones in like manner
terminate in white."

A very singular little bird, Tinochorus rumicivorus, is here common: in
its habits and general appearance, it nearly equally partakes of the
characters, different as they are, of the quail and snipe.  The
Tinochorus is found in the whole of southern South America, wherever
there are sterile plains, or open dry pasture land.  It frequents in
pairs or small flocks the most desolate places, where scarcely another
living creature can exist.  Upon being approached they squat close, and
then are very difficult to be distinguished from the ground.  When
feeding they walk rather slowly, with their legs wide apart.  They dust
themselves in roads and sandy places, and frequent particular spots,
where they may be found day after day: like partridges, they take wing
in a flock.  In all these respects, in the muscular gizzard adapted for
vegetable food, in the arched beak and fleshy nostrils, short legs and
form of foot, the Tinochorus has a close affinity with quails.  But as
soon as the bird is seen flying, its whole appearance changes; the long
pointed wings, so different from those in the gallinaceous order, the
irregular manner of flight, and plaintive cry uttered at the moment of
rising, recall the idea of a snipe.  The sportsmen of the Beagle
unanimously called it the short-billed snipe.  To this genus, or rather
to the family of the Waders, its skeleton shows that it is really
related.

The Tinochorus is closely related to some other South American birds.
Two species of the genus Attagis are in almost every respect ptarmigans
in their habits; one lives in Tierra del Fuego, above the limits of the
forest land; and the other just beneath the snow-line on the Cordillera
of Central Chile.  A bird of another closely allied genus, Chionis
alba, is an inhabitant of the antarctic regions; it feeds on sea-weed
and shells on the tidal rocks.  Although not web footed, from some
unaccountable habit, it is frequently met with far out at sea.  This
small family of birds is one of those which, from its varied relations
to other families, although at present offering only difficulties to
the systematic naturalist, ultimately may assist in revealing the grand
scheme, common to the present and past ages, on which organized beings
have been created.

The genus Furnarius contains several species, all small birds, living
on the ground, and inhabiting open dry countries. In structure they
cannot be compared to any European form.  Ornithologists have generally
included them among the creepers, although opposed to that family in
every habit.  The best known species is the common oven-bird of La
Plata, the Casara or housemaker of the Spaniards.  The nest, whence it
takes its name, is placed in the most exposed situations, as on the top
of a post, a bare rock, or on a cactus.  It is composed of mud and bits
of straw, and has strong thick walls: in shape it precisely resembles
an oven, or depressed beehive.  The opening is large and arched, and
directly in front, within the nest, there is a partition, which reaches
nearly to the roof, thus forming a passage or antechamber to the true
nest.

Another and smaller species of Furnarius (F. cunicularius), resembles
the oven-bird in the general reddish tint of its plumage, in a peculiar
shrill reiterated cry, and in an odd manner of running by starts.  From
its affinity, the Spaniards call it Casarita (or little housebuilder),
although its nidification is quite different.  The Casarita builds its
nest at the bottom of a narrow cylindrical hole, which is said to
extend horizontally to nearly six feet under ground. Several of the
country people told me, that when boys, they had attempted to dig out
the nest, but had scarcely ever succeeded in getting to the end of the
passage.  The bird chooses any low bank of firm sandy soil by the side
of a road or stream.  Here (at Bahia Blanca) the walls round the houses
are built of hardened mud, and I noticed that one, which enclosed a
courtyard where I lodged, was bored through by round holes in a score
of places.  On asking the owner the cause of this he bitterly
complained of the little casarita, several of which I afterwards
observed at work. It is rather curious to find how incapable these
birds must be of acquiring any notion of thickness, for although they
were constantly flitting over the low wall, they continued vainly to
bore through it, thinking it an excellent bank for their nests.  I do
not doubt that each bird, as often as it came to daylight on the
opposite side, was greatly surprised at the marvellous fact.

I have already mentioned nearly all the mammalia common in this
country.  Of armadilloes three species occur namely, the Dasypus
minutus or _pichy_, the D. villosus or _peludo_, and the _apar_.  The
first extends ten degrees further south than any other kind; a fourth
species, the _Mulita_, does not come as far south as Bahia Blanca.  The
four species have nearly similar habits; the _peludo_, however, is
nocturnal, while the others wander by day over the open plains, feeding
on beetles, larvae, roots, and even small snakes.  The _apar_, commonly
called _mataco_, is remarkable by having only three moveable bands; the
rest of its tesselated covering being nearly inflexible.  It has the
power of rolling itself into a perfect sphere, like one kind of English
woodlouse. In this state it is safe from the attack of dogs; for the
dog not being able to take the whole in its mouth, tries to bite one
side, and the ball slips away.  The smooth hard covering of the
_mataco_ offers a better defence than the sharp spines of the hedgehog.
The _pichy_ prefers a very dry soil; and the sand-dunes near the coast,
where for many months it can never taste water, is its favourite
resort: it often tries to escape notice, by squatting close to the
ground.  In the course of a day's ride, near Bahia Blanca, several were
generally met with.  The instant one was perceived, it was necessary,
in order to catch it, almost to tumble off one's horse; for in soft
soil the animal burrowed so quickly, that its hinder quarters would
almost disappear before one could alight.  It seems almost a pity to
kill such nice little animals, for as a Gaucho said, while sharpening
his knife on the back of one, "Son tan mansos" (they are so quiet).

Of reptiles there are many kinds: one snake (a Trigonocephalus, or
Cophias [18]), from the size of the poison channel in its fangs, must
be very deadly.  Cuvier, in opposition to some other naturalists, makes
this a sub-genus of the rattlesnake, and intermediate between it and
the viper.  In confirmation of this opinion, I observed a fact, which
appears to me very curious and instructive, as showing how every
character, even though it may be in some degree independent of
structure, has a tendency to vary by slow degrees. The extremity of the
tail of this snake is terminated by a point, which is very slightly
enlarged; and as the animal glides along, it constantly vibrates the
last inch; and this part striking against the dry grass and brushwood,
produces a rattling noise, which can be distinctly heard at the
distance of six feet.  As often as the animal was irritated or
surprised, its tail was shaken; and the vibrations were extremely
rapid.  Even as long as the body retained its irritability, a tendency
to this habitual movement was evident. This Trigonocephalus has,
therefore, in some respects the structure of a viper, with the habits
of a rattlesnake: the noise, however, being produced by a simpler
device.  The expression of this snake's face was hideous and fierce;
the pupil consisted of a vertical slit in a mottled and coppery iris;
the jaws were broad at the base, and the nose terminated in a
triangular projection.  I do not think I ever saw anything more ugly,
excepting, perhaps, some of the vampire bats.  I imagine this repulsive
aspect originates from the features being placed in positions, with
respect to each other, somewhat proportional to those of the human
face; and thus we obtain a scale of hideousness.

Amongst the Batrachian reptiles, I found only one little toad
(Phryniscus nigricans), which was most singular from its colour.  If we
imagine, first, that it had been steeped in the blackest ink, and then,
when dry, allowed to crawl over a board, freshly painted with the
brightest vermilion, so as to colour the soles of its feet and parts of
its stomach, a good idea of its appearance will be gained.  If it had
been an unnamed species, surely it ought to have been called
_Diabolicus_, for it is a fit toad to preach in the ear of Eve. Instead
of being nocturnal in its habits, as other toads are, and living in
damp obscure recesses, it crawls during the heat of the day about the
dry sand-hillocks and arid plains, where not a single drop of water can
be found.  It must necessarily depend on the dew for its moisture; and
this probably is absorbed by the skin, for it is known, that these
reptiles possess great powers of cutaneous absorption.  At Maldonado, I
found one in a situation nearly as dry as at Bahia Blanca, and thinking
to give it a great treat, carried it to a pool of water; not only was
the little animal unable to swim, but I think without help it would
soon have been drowned. Of lizards there were many kinds, but only one
(Proctotretus multimaculatus) remarkable from its habits.  It lives on
the bare sand near the sea coast, and from its mottled colour, the
brownish scales being speckled with white, yellowish red, and dirty
blue, can hardly be distinguished from the surrounding surface.  When
frightened, it attempts to avoid discovery by feigning death, with
outstretched legs, depressed body, and closed eyes: if further
molested, it buries itself with great quickness in the loose sand. This
lizard, from its flattened body and short legs, cannot run quickly.

I will here add a few remarks on the hybernation of animals in this
part of South America.  When we first arrived at Bahia Blanca,
September 7th, 1832, we thought nature had granted scarcely a living
creature to this sandy and dry country.  By digging, however, in the
ground, several insects, large spiders, and lizards were found in a
half-torpid state.  On the 15th, a few animals began to appear, and by
the 18th (three days from the equinox), everything announced the
commencement of spring.  The plains were ornamented by the flowers of a
pink wood-sorrel, wild peas, cenotherae, and geraniums; and the birds
began to lay their eggs.  Numerous Lamellicorn and Heteromerous
insects, the latter remarkable for their deeply sculptured bodies, were
slowly crawling about; while the lizard tribe, the constant inhabitants
of a sandy soil, darted about in every direction. During the first
eleven days, whilst nature was dormant, the mean temperature taken from
observations made every two hours on board the Beagle, was 51 degs.;
and in the middle of the day the thermometer seldom ranged above 55
degs.  On the eleven succeeding days, in which all living things became
so animated, the mean was 58 degs., and the range in the middle of the
day between 60 and 70 degs.  Here, then, an increase of seven degrees
in mean temperature, but a greater one of extreme heat, was sufficient
to awake the functions of life. At Monte Video, from which we had just
before sailed, in the twenty-three days included between the 26th of
July and the 19th of August, the mean temperature from 276 observations
was 58.4 degs.; the mean hottest day being 65.5 degs., and the coldest
46 degs.  The lowest point to which the thermometer fell was 41.5
degs., and occasionally in the middle of the day it rose to 69 or 70
degs. Yet with this high temperature, almost every beetle, several
genera of spiders, snails, and land-shells, toads and lizards were all
lying torpid beneath stones.  But we have seen that at Bahia Blanca,
which is four degrees southward and therefore with a climate only a
very little colder, this same temperature with a rather less extreme
heat, was sufficient to awake all orders of animated beings. This shows
how nicely the stimulus required to arouse hybernating animals is
governed by the usual climate of the district, and not by the absolute
heat.  It is well known that within the tropics, the hybernation, or
more properly aestivation, of animals is determined not by the
temperature, but by the times of drought.  Near Rio de Janeiro, I was
at first surprised to observe, that, a few days after some little
depressions had been filled with water, they were peopled by numerous
full-grown shells and beetles, which must have been lying dormant.
Humboldt has related the strange accident of a hovel having been
erected over a spot where a young crocodile lay buried in the hardened
mud.  He adds, "The Indians often find enormous boas, which they call
Uji or water serpents, in the same lethargic state.  To reanimate them,
they must be irritated or wetted with water."

I will only mention one other animal, a zoophyte (I believe Virgularia
Patagonica), a kind of sea-pen.  It consists of a thin, straight,
fleshy stem, with alternate rows of polypi on each side, and
surrounding an elastic stony axis, varying in length from eight inches
to two feet.  The stem at one extremity is truncate, but at the other
is terminated by a vermiform fleshy appendage.  The stony axis which
gives strength to the stem may be traced at this extremity into a mere
vessel filled with granular matter.  At low water hundreds of these
zoophytes might be seen, projecting like stubble, with the truncate end
upwards, a few inches above the surface of the muddy sand.  When
touched or pulled they suddenly drew themselves in with force, so as
nearly or quite to disappear.  By this action, the highly elastic axis
must be bent at the lower extremity, where it is naturally slightly
curved; and I imagine it is by this elasticity alone that the zoophyte
is enabled to rise again through the mud.  Each polypus, though closely
united to its brethren, has a distinct mouth, body, and tentacula.  Of
these polypi, in a large specimen, there must be many thousands; yet we
see that they act by one movement: they have also one central axis
connected with a system of obscure circulation, and the ova are
produced in an organ distinct from the separate individuals. [19] Well
may one be allowed to ask, what is an individual?  It is always
interesting to discover the foundation of the strange tales of the old
voyagers; and I have no doubt but that the habits of this Virgularia
explain one such case. Captain Lancaster, in his voyage [20] in 1601,
narrates that on the sea-sands of the Island of Sombrero, in the East
Indies, he "found a small twig growing up like a young tree, and on
offering to pluck it up it shrinks down to the ground, and sinks,
unless held very hard.  On being plucked up, a great worm is found to
be its root, and as the tree groweth in greatness, so doth the worm
diminish, and as soon as the worm is entirely turned into a tree it
rooteth in the earth, and so becomes great.  This transformation is one
of the strangest wonders that I saw in all my travels: for if this tree
is plucked up, while young, and the leaves and bark stripped off, it
becomes a hard stone when dry, much like white coral: thus is this worm
twice transformed into different natures.  Of these we gathered and
brought home many."


During my stay at Bahia Blanca, while waiting for the Beagle, the place
was in a constant state of excitement, from rumours of wars and
victories, between the troops of Rosas and the wild Indians.  One day
an account came that a small party forming one of the postas on the
line to Buenos Ayres, had been found all murdered.  The next day three
hundred men arrived from the Colorado, under the command of Commandant
Miranda.  A large portion of these men were Indians (mansos, or tame),
belonging to the tribe of the Cacique Bernantio.  They passed the night
here; and it was impossible to conceive anything more wild and savage
than the scene of their bivouac.  Some drank till they were
intoxicated; others swallowed the steaming blood of the cattle
slaughtered for their suppers, and then, being sick from drunkenness,
they cast it up again, and were besmeared with filth and gore.

Nam simul expletus dapibus, vinoque sepultus Cervicem inflexam posuit,
jacuitque per antrum Immensus, saniem eructans, ac frusta cruenta Per
somnum commixta mero.

In the morning they started for the scene of the murder, with orders to
follow the "rastro," or track, even if it led them to Chile.  We
subsequently heard that the wild Indians had escaped into the great
Pampas, and from some cause the track had been missed.  One glance at
the rastro tells these people a whole history.  Supposing they examine
the track of a thousand horses, they will soon guess the number of
mounted ones by seeing how many have cantered; by the depth of the
other impressions, whether any horses were loaded with cargoes; by the
irregularity of the footsteps, how far tired; by the manner in which
the food has been cooked, whether the pursued travelled in haste; by
the general appearance, how long it has been since they passed. They
consider a rastro of ten days or a fortnight, quite recent enough to be
hunted out.  We also heard that Miranda struck from the west end of the
Sierra Ventana, in a direct line to the island of Cholechel, situated
seventy leagues up the Rio Negro.  This is a distance of between two
and three hundred miles, through a country completely unknown. What
other troops in the world are so independent?  With the sun for their
guide, mare's flesh for food, their saddle-cloths for beds,--as long as
there is a little water, these men would penetrate to the end of the
world.

A few days afterwards I saw another troop of these banditti-like
soldiers start on an expedition against a tribe of Indians at the small
Salinas, who had been betrayed by a prisoner cacique.  The Spaniard who
brought the orders for this expedition was a very intelligent man.  He
gave me an account of the last engagement at which he was present. Some
Indians, who had been taken prisoners, gave information of a tribe
living north of the Colorado.  Two hundred soldiers were sent; and they
first discovered the Indians by a cloud of dust from their horses'
feet, as they chanced to be travelling.  The country was mountainous
and wild, and it must have been far in the interior, for the Cordillera
were in sight.  The Indians, men, women, and children, were about one
hundred and ten in number, and they were nearly all taken or killed,
for the soldiers sabre every man.  The Indians are now so terrified
that they offer no resistance in a body, but each flies, neglecting
even his wife and children; but when overtaken, like wild animals, they
fight against any number to the last moment.  One dying Indian seized
with his teeth the thumb of his adversary, and allowed his own eye to
be forced out sooner than relinquish his hold.  Another, who was
wounded, feigned death, keeping a knife ready to strike one more fatal
blow.  My informer said, when he was pursuing an Indian, the man cried
out for mercy, at the same time that he was covertly loosing the bolas
from his waist, meaning to whirl it round his head and so strike his
pursuer.  "I however struck him with my sabre to the ground, and then
got off my horse, and cut his throat with my knife." This is a dark
picture; but how much more shocking is the unquestionable fact, that
all the women who appear above twenty years old are massacred in cold
blood! When I exclaimed that this appeared rather inhuman, he answered,
"Why, what can be done? they breed so!"

Every one here is fully convinced that this is the most just war,
because it is against barbarians.  Who would believe in this age that
such atrocities could be committed in a Christian civilized country?
The children of the Indians are saved, to be sold or given away as
servants, or rather slaves for as long a time as the owners can make
them believe themselves slaves; but I believe in their treatment there
is little to complain of.

In the battle four men ran away together.  They were pursued, one was
killed, and the other three were taken alive. They turned out to be
messengers or ambassadors from a large body of Indians, united in the
common cause of defence, near the Cordillera.  The tribe to which they
had been sent was on the point of holding a grand council, the feast of
mare's flesh was ready, and the dance prepared: in the morning the
ambassadors were to have returned to the Cordillera.  They were
remarkably fine men, very fair, above six feet high, and all under
thirty years of age.  The three survivors of course possessed very
valuable information and to extort this they were placed in a line. The
two first being questioned, answered, "No se" (I do not know), and were
one after the other shot.  The third also said "No se;" adding, "Fire,
I am a man, and can die!" Not one syllable would they breathe to injure
the united cause of their country! The conduct of the above-mentioned
cacique was very different; he saved his life by betraying the intended
plan of warfare, and the point of union in the Andes.  It was believed
that there were already six or seven hundred Indians together, and that
in summer their numbers would be doubled. Ambassadors were to have been
sent to the Indians at the small Salinas, near Bahia Blanca, whom I
have mentioned that this same cacique had betrayed.  The communication,
therefore, between the Indians, extends from the Cordillera to the
coast of the Atlantic.

General Rosas's plan is to kill all stragglers, and having driven the
remainder to a common point, to attack them in a body, in the summer,
with the assistance of the Chilenos. This operation is to be repeated
for three successive years. I imagine the summer is chosen as the time
for the main attack, because the plains are then without water, and the
Indians can only travel in particular directions.  The escape of the
Indians to the south of the Rio Negro, where in such a vast unknown
country they would be safe, is prevented by a treaty with the
Tehuelches to this effect;--that Rosas pays them so much to slaughter
every Indian who passes to the south of the river, but if they fail in
so doing, they themselves are to be exterminated.  The war is waged
chiefly against the Indians near the Cordillera; for many of the tribes
on this eastern side are fighting with Rosas.  The general, however,
like Lord Chesterfield, thinking that his friends may in a future day
become his enemies, always places them in the front ranks, so that
their numbers may be thinned.  Since leaving South America we have
heard that this war of extermination completely failed.

Among the captive girls taken in the same engagement, there were two
very pretty Spanish ones, who had been carried away by the Indians when
young, and could now only speak the Indian tongue.  From their account
they must have come from Salta, a distance in a straight line of nearly
one thousand miles.  This gives one a grand idea of the immense
territory over which the Indians roam: yet, great as it is, I think
there will not, in another half-century, be a wild Indian northward of
the Rio Negro.  The warfare is too bloody to last; the Christians
killing every Indian, and the Indians doing the same by the Christians.
It is melancholy to trace how the Indians have given way before the
Spanish invaders.  Schirdel [21] says that in 1535, when Buenos Ayres
was founded, there were villages containing two and three thousand
inhabitants.  Even in Falconer's time (1750) the Indians made inroads
as far as Luxan, Areco, and Arrecife, but now they are driven beyond
the Salado.  Not only have whole tribes been exterminated, but the
remaining Indians have become more barbarous: instead of living in
large villages, and being employed in the arts of fishing, as well as
of the chase, they now wander about the open plains, without home or
fixed occupation.

I heard also some account of an engagement which took place, a few
weeks previously to the one mentioned, at Cholechel.  This is a very
important station on account of being a pass for horses; and it was, in
consequence, for some time the head-quarters of a division of the army.
When the troops first arrived there they found a tribe of Indians, of
whom they killed twenty or thirty.  The cacique escaped in a manner
which astonished every one.  The chief Indians always have one or two
picked horses, which they keep ready for any urgent occasion.  On one
of these, an old white horse, the cacique sprung, taking with him his
little son.  The horse had neither saddle nor bridle.  To avoid the
shots, the Indian rode in the peculiar method of his nation namely,
with an arm round the horse's neck, and one leg only on its back.  Thus
hanging on one side, he was seen patting the horse's head, and talking
to him.  The pursuers urged every effort in the chase; the Commandant
three times changed his horse, but all in vain.  The old Indian father
and his son escaped, and were free.  What a fine picture one can form
in one's mind,--the naked, bronze-like figure of the old man with his
little boy, riding like a Mazeppa on the white horse, thus leaving far
behind him the host of his pursuers!

I saw one day a soldier striking fire with a piece of flint, which I
immediately recognised as having been a part of the head of an arrow.
He told me it was found near the island of Cholechel, and that they are
frequently picked up there. It was between two and three inches long,
and therefore twice as large as those now used in Tierra del Fuego: it
was made of opaque cream-coloured flint, but the point and barbs had
been intentionally broken off.  It is well known that no Pampas Indians
now use bows and arrows.  I believe a small tribe in Banda Oriental
must be excepted; but they are widely separated from the Pampas
Indians, and border close on those tribes that inhabit the forest, and
live on foot.  It appears, therefore, that these arrow-heads are
antiquarian [22] relics of the Indians, before the great change in
habits consequent on the introduction of the horse into South America.

[1] Since this was written, M. Alcide d'Orbingy has examined these
shells, and pronounces them all to be recent.

[2] M. Aug. Bravard has described, in a Spanish work ('Observaciones
Geologicas,' 1857), this district, and he believes that the bones of
the extinct mammals were washed out of the underlying Pampean deposit,
and subsequently became embedded with the still existing shells; but I
am not convinced by his remarks.  M. Bravard believes that the whole
enormous Pampean deposit is a sub-aerial formation, like sand-dunes:
this seems to me to be an untenable doctrine.

[3] Principles of Geology, vol. iv. p. 40.

[4] This theory was first developed in the Zoology of the Voyage of the
Beagle, and subsequently in Professor Owen's Memoir on Mylodon robustus.

[5] I mean this to exclude the total amount which may have been
successively produced and consumed during a given period.

[6] Travels in the Interior of South Africa, vol. ii. p. 207

[7] The elephant which was killed at Exeter Change was estimated (being
partly weighed) at five tons and a half. The elephant actress, as I was
informed, weighed one ton less; so that we may take five as the average
of a full-grown elephant.  I was told at the Surry Gardens, that a
hippopotamus which was sent to England cut up into pieces was estimated
at three tons and a half; we will call it three.  From these premises
we may give three tons and a half to each of the five rhinoceroses;
perhaps a ton to the giraffe, and half to the bos caffer as well as to
the elan (a large ox weighs from 1200 to 1500 pounds).  This will give
an average (from the above estimates) of 2.7 of a ton for the ten
largest herbivorous animals of Southern Africa.  In South America,
allowing 1200 pounds for the two tapirs together, 550 for the guanaco
and vicuna, 500 for three deer, 300 for the capybara, peccari, and a
monkey, we shall have an average of 250 pounds, which I believe is
overstating the result.  The ratio will therefore be as 6048 to 250, or
24 to 1, for the ten largest animals from the two continents.

[8] If we suppose the case of the discovery of a skeleton of a
Greenland whale in a fossil state, not a single cetaceous animal being
known to exist, what naturalist would have ventured conjecture on the
possibility of a carcass so gigantic being supported on the minute
crustacea and mollusca living in the frozen seas of the extreme North?

[9] See Zoological Remarks to Capt. Back's Expedition, by Dr.
Richardson.  He says, "The subsoil north of latitude 56 degs. is
perpetually frozen, the thaw on the coast not penetrating above three
feet, and at Bear Lake, in latitude 64 degs., not more than twenty
inches.  The frozen substratum does not of itself destroy vegetation,
for forests flourish on the surface, at a distance from the coast."

[10] See Humboldt, Fragments Asiatiques, p. 386: Barton's Geography of
Plants: and Malte Brun.  In the latter work it is said that the limit
of the growth of trees in Siberia may be drawn under the parallel of 70
degs.

[11] Sturt's Travels, vol. ii. p. 74.

[12] A Gaucho assured me that he had once seen a snow-white or Albino
variety, and that it was a most beautiful bird.

[13] Burchell's Travels, vol. i. p. 280.

[14] Azara, vol. iv. p. 173.

[15] Lichtenstein, however, asserts (Travels, vol. ii. p. 25) that the
hens begin sitting when they have laid ten or twelve eggs; and that
they continue laying, I presume, in another nest.  This appears to me
very improbable.  He asserts that four or five hens associate for
incubation with one cock, who sits only at night.

[16] When at the Rio Negro, we heard much of the indefatigable labours
of this naturalist.  M. Alcide d'Orbigny, during the years 1825 to
1833, traversed several large portions of South America, and has made a
collection, and is now publishing the results on a scale of
magnificence, which at once places himself in the list of American
travellers second only to Humboldt.

[17] Account of the Abipones, A.D. 1749, vol. i. (English Translation)
p. 314

[18] M. Bibron calls it T. crepitans.


[19] The cavities leading from the fleshy compartments of the
extremity, were filled with a yellow pulpy matter, which, examined
under a microscope, presented an extraordinary appearance.  The mass
consisted of rounded, semi-transparent, irregular grains, aggregated
together into particles of various sizes.  All such particles, and the
separate grains, possessed the power of rapid movement; generally
revolving around different axes, but sometimes progressive.  The
movement was visible with a very weak power, but even with the highest
its cause could not be perceived.  It was very different from the
circulation of the fluid in the elastic bag, containing the thin
extremity of the axis.  On other occasions, when dissecting small
marine animals beneath the microscope, I have seen particles of pulpy
matter, some of large size, as soon as they were disengaged, commence
revolving.  I have imagined, I know not with how much truth, that this
granulo-pulpy matter was in process of being converted into ova.
Certainly in this zoophyte such appeared to be the case.

[20] Kerr's Collection of Voyages, vol. viii. p. 119.

[21] Purchas's Collection of Voyages.  I believe the date was really
1537.

[22] Azara has even doubted whether the Pampas Indians ever used bows.



CHAPTER VI

BAHIA BLANCA TO BUENOS AYRES

Set out for Buenos Ayres--Rio Sauce--Sierra Ventana--Third
Posta--Driving Horses--Bolas--Partridges and Foxes--Features of the
Country--Long-legged Plover--Teru-tero--Hail-storm--Natural Enclosures
in the Sierra Tapalguen--Flesh of Puma--Meat Diet--Guardia del
Monte--Effects of Cattle on the Vegetation--Cardoon--Buenos
Ayres--Corral where Cattle are Slaughtered.


SEPTEMBER 18th.--I hired a Gaucho to accompany me on my ride to Buenos
Ayres, though with some difficulty, as the father of one man was afraid
to let him go, and another, who seemed willing, was described to me as
so fearful, that I was afraid to take him, for I was told that even if
he saw an ostrich at a distance, he would mistake it for an Indian, and
would fly like the wind away. The distance to Buenos Ayres is about
four hundred miles, and nearly the whole way through an uninhabited
country. We started early in the morning; ascending a few hundred feet
from the basin of green turf on which Bahia Blanca stands, we entered
on a wide desolate plain.  It consists of a crumbling
argillaceo-calcareous rock, which, from the dry nature of the climate,
supports only scattered tufts of withered grass, without a single bush
or tree to break the monotonous uniformity.  The weather was fine, but
the atmosphere remarkably hazy; I thought the appearance foreboded a
gale, but the Gauchos said it was owing to the plain, at some great
distance in the interior, being on fire.  After a long gallop, having
changed horses twice, we reached the Rio Sauce: it is a deep, rapid,
little stream, not above twenty-five feet wide.  The second posta on
the road to Buenos Ayres stands on its banks, a little above there is a
ford for horses, where the water does not reach to the horses' belly;
but from that point, in its course to the sea, it is quite impassable,
and hence makes a most useful barrier against the Indians.

Insignificant as this stream is, the Jesuit Falconer, whose information
is generally so very correct, figures it as a considerable river,
rising at the foot of the Cordillera.  With respect to its source, I do
not doubt that this is the case for the Gauchos assured me, that in the
middle of the dry summer, this stream, at the same time with the
Colorado has periodical floods; which can only originate in the snow
melting on the Andes.  It is extremely improbable that a stream so
small as the Sauce then was, should traverse the entire width of the
continent; and indeed, if it were the residue of a large river, its
waters, as in other ascertained cases, would be saline.  During the
winter we must look to the springs round the Sierra Ventana as the
source of its pure and limpid stream.  I suspect the plains of
Patagonia like those of Australia, are traversed by many water-courses
which only perform their proper parts at certain periods. Probably this
is the case with the water which flows into the head of Port Desire,
and likewise with the Rio Chupat, on the banks of which masses of
highly cellular scoriae were found by the officers employed in the
survey.

As it was early in the afternoon when we arrived, we took fresh horses,
and a soldier for a guide, and started for the Sierra de la Ventana.
This mountain is visible from the anchorage at Bahia Blanca; and Capt.
Fitz Roy calculates its height to be 3340 feet--an altitude very
remarkable on this eastern side of the continent.  I am not aware that
any foreigner, previous to my visit, had ascended this mountain; and
indeed very few of the soldiers at Bahia Blanca knew anything about it.
Hence we heard of beds of coal, of gold and silver, of caves, and of
forests, all of which inflamed my curiosity, only to disappoint it. The
distance from the posta was about six leagues over a level plain of the
same character as before.  The ride was, however, interesting, as the
mountain began to show its true form.  When we reached the foot of the
main ridge, we had much difficulty in finding any water, and we thought
we should have been obliged to have passed the night without any.  At
last we discovered some by looking close to the mountain, for at the
distance even of a few hundred yards the streamlets were buried and
entirely lost in the friable calcareous stone and loose detritus. I do
not think Nature ever made a more solitary, desolate pile of rock;--it
well deserves its name of _Hurtado_, or separated.  The mountain is
steep, extremely rugged, and broken, and so entirely destitute of
trees, and even bushes, that we actually could not make a skewer to
stretch out our meat over the fire of thistle-stalks. [1] The strange
aspect of this mountain is contrasted by the sea-like plain, which not
only abuts against its steep sides, but likewise separates the parallel
ranges.  The uniformity of the colouring gives an extreme quietness to
the view,--the whitish grey of the quartz rock, and the light brown of
the withered grass of the plain, being unrelieved by any brighter tint.
From custom, one expects to see in the neighbourhood of a lofty and
bold mountain, a broken country strewed over with huge fragments. Here
nature shows that the last movement before the bed of the sea is
changed into dry land may sometimes be one of tranquillity. Under these
circumstances I was curious to observe how far from the parent rock any
pebbles could be found.  On the shores of Bahia Blanca, and near the
settlement, there were some of quartz, which certainly must have come
from this source: the distance is forty-five miles.

The dew, which in the early part of the night wetted the saddle-cloths
under which we slept, was in the morning frozen.  The plain, though
appearing horizontal, had insensibly sloped up to a height of between
800 and 900 feet above the sea.  In the morning (9th of September) the
guide told me to ascend the nearest ridge, which he thought would lead
me to the four peaks that crown the summit.  The climbing up such rough
rocks was very fatiguing; the sides were so indented, that what was
gained in one five minutes was often lost in the next.  At last, when I
reached the ridge, my disappointment was extreme in finding a
precipitous valley as deep as the plain, which cut the chain
transversely in two, and separated me from the four points.  This
valley is very narrow, but flat-bottomed, and it forms a fine
horse-pass for the Indians, as it connects the plains on the northern
and southern sides of the range.  Having descended, and while crossing
it, I saw two horses grazing: I immediately hid myself in the long
grass, and began to reconnoitre; but as I could see no signs of Indians
I proceeded cautiously on my second ascent.  It was late in the day,
and this part of the mountain, like the other, was steep and rugged.  I
was on the top of the second peak by two o'clock, but got there with
extreme difficulty; every twenty yards I had the cramp in the upper
part of both thighs, so that I was afraid I should not have been able
to have got down again.  It was also necessary to return by another
road, as it was out of the question to pass over the saddle-back.  I
was therefore obliged to give up the two higher peaks.  Their altitude
was but little greater, and every purpose of geology had been answered;
so that the attempt was not worth the hazard of any further exertion. I
presume the cause of the cramp was the great change in the kind of
muscular action, from that of hard riding to that of still harder
climbing.  It is a lesson worth remembering, as in some cases it might
cause much difficulty.

I have already said the mountain is composed of white quartz rock, and
with it a little glossy clay-slate is associated.  At the height of a
few hundred feet above the plain patches of conglomerate adhered in
several places to the solid rock.  They resembled in hardness, and in
the nature of the cement, the masses which may be seen daily forming on
some coasts.  I do not doubt these pebbles were in a similar manner
aggregated, at a period when the great calcareous formation was
depositing beneath the surrounding sea. We may believe that the jagged
and battered forms of the hard quartz yet show the effects of the waves
of an open ocean.

I was, on the whole, disappointed with this ascent.  Even the view was
insignificant;--a plain like the sea, but without its beautiful colour
and defined outline.  The scene, however, was novel, and a little
danger, like salt to meat, gave it a relish.  That the danger was very
little was certain, for my two companions made a good fire--a thing
which is never done when it is suspected that Indians are near. I
reached the place of our bivouac by sunset, and drinking much mate, and
smoking several cigaritos, soon made up my bed for the night.  The wind
was very strong and cold, but I never slept more comfortably.

September 10th.--In the morning, having fairly scudded before the gale,
we arrived by the middle of the day at the Sauce posta.  In the road we
saw great numbers of deer, and near the mountain a guanaco. The plain,
which abuts against the Sierra, is traversed by some curious gullies,
of which one was about twenty feet wide, and at least thirty deep; we
were obliged in consequence to make a considerable circuit before we
could find a pass.  We stayed the night at the posta, the conversation,
as was generally the case, being about the Indians.  The Sierra Ventana
was formerly a great place of resort; and three or four years ago there
was much fighting there.  My guide had been present when many Indians
were killed: the women escaped to the top of the ridge, and fought most
desperately with great stones; many thus saving themselves.

September 11th.--Proceeded to the third posta in company with the
lieutenant who commanded it.  The distance is called fifteen leagues;
but it is only guess-work, and is generally overstated.  The road was
uninteresting, over a dry grassy plain; and on our left hand at a
greater or less distance there were some low hills; a continuation of
which we crossed close to the posta.  Before our arrival we met a large
herd of cattle and horses, guarded by fifteen soldiers; but we were
told many had been lost.  It is very difficult to drive animals across
the plains; for if in the night a puma, or even a fox, approaches,
nothing can prevent the horses dispersing in every direction; and a
storm will have the same effect.  A short time since, an officer left
Buenos Ayres with five hundred horses, and when he arrived at the army
he had under twenty.

Soon afterwards we perceived by the cloud of dust, that a party of
horsemen were coming towards us; when far distant my companions knew
them to be Indians, by their long hair streaming behind their backs.
The Indians generally have a fillet round their heads, but never any
covering; and their black hair blowing across their swarthy faces,
heightens to an uncommon degree the wildness of their appearance. They
turned out to be a party of Bernantio's friendly tribe, going to a
salina for salt.  The Indians eat much salt, their children sucking it
like sugar.  This habit is very different from that of the Spanish
Gauchos, who, leading the same kind of life, eat scarcely any;
according to Mungo Park, [2] it is people who live on vegetable food
who have an unconquerable desire for salt.  The Indians gave us
good-humoured nods as they passed at full gallop, driving before them a
troop of horses, and followed by a train of lanky dogs.

September 12th and 13th.--I stayed at this posta two days, waiting for
a troop of soldiers, which General Rosas had the kindness to send to
inform me, would shortly travel to Buenos Ayres; and he advised me to
take the opportunity of the escort.  In the morning we rode to some
neighbouring hills to view the country, and to examine the geology.
After dinner the soldiers divided themselves into two parties for a
trial of skill with the bolas.  Two spears were stuck in the ground
twenty-five yards apart, but they were struck and entangled only once
in four or five times.  The balls can be thrown fifty or sixty yards,
but with little certainty. This, however, does not apply to a man on
horseback; for when the speed of the horse is added to the force of the
arm, it is said, that they can be whirled with effect to the distance
of eighty yards.  As a proof of their force, I may mention, that at the
Falkland Islands, when the Spaniards murdered some of their own
countrymen and all the Englishmen, a young friendly Spaniard was
running away, when a great tall man, by name Luciano, came at full
gallop after him, shouting to him to stop, and saying that he only
wanted to speak to him.  Just as the Spaniard was on the point of
reaching the boat, Luciano threw the balls: they struck him on the legs
with such a jerk, as to throw him down and to render him for some time
insensible.  The man, after Luciano had had his talk, was allowed to
escape.  He told us that his legs were marked by great weals, where the
thong had wound round, as if he had been flogged with a whip. In the
middle of the day two men arrived, who brought a parcel from the next
posta to be forwarded to the general: so that besides these two, our
party consisted this evening of my guide and self, the lieutenant, and
his four soldiers. The latter were strange beings; the first a fine
young negro; the second half Indian and negro; and the two others
non-descripts; namely, an old Chilian miner, the colour of mahogany,
and another partly a mulatto; but two such mongrels with such
detestable expressions, I never saw before. At night, when they were
sitting round the fire, and playing at cards, I retired to view such a
Salvator Rosa scene.  They were seated under a low cliff, so that I
could look down upon them; around the party were lying dogs, arms,
remnants of deer and ostriches; and their long spears were stuck in the
turf.  Further in the dark background, their horses were tied up, ready
for any sudden danger.  If the stillness of the desolate plain was
broken by one of the dogs barking, a soldier, leaving the fire, would
place his head close to the ground, and thus slowly scan the horizon.
Even if the noisy teru-tero uttered its scream, there would be a pause
in the conversation, and every head, for a moment, a little inclined.

What a life of misery these men appear to us to lead! They were at
least ten leagues from the Sauce posta, and since the murder committed
by the Indians, twenty from another.  The Indians are supposed to have
made their attack in the middle of the night; for very early in the
morning after the murder, they were luckily seen approaching this
posta.  The whole party here, however, escaped, together with the troop
of horses; each one taking a line for himself, and driving with him as
many animals as he was able to manage.

The little hovel, built of thistle-stalks, in which they slept, neither
kept out the wind nor rain; indeed in the latter case the only effect
the roof had, was to condense it into larger drops.  They had nothing
to eat excepting what they could catch, such as ostriches, deer,
armadilloes, etc., and their only fuel was the dry stalks of a small
plant, somewhat resembling an aloe.  The sole luxury which these men
enjoyed was smoking the little paper cigars, and sucking mate.  I used
to think that the carrion vultures, man's constant attendants on these
dreary plains, while seated on the little neighbouring cliffs seemed by
their very patience to say, "Ah! when the Indians come we shall have a
feast."

In the morning we all sallied forth to hunt, and although we had not
much success, there were some animated chases. Soon after starting the
party separated, and so arranged their plans, that at a certain time of
the day (in guessing which they show much skill) they should all meet
from different points of the compass on a plain piece of ground, and
thus drive together the wild animals.  One day I went out hunting at
Bahia Blanca, but the men there merely rode in a crescent, each being
about a quarter of a mile apart from the other.  A fine male ostrich
being turned by the headmost riders, tried to escape on one side.  The
Gauchos pursued at a reckless pace, twisting their horses about with
the most admirable command, and each man whirling the balls round his
head.  At length the foremost threw them, revolving through the air: in
an instant the ostrich rolled over and over, its legs fairly lashed
together by the thong. The plains abound with three kinds of partridge,
[3] two of which are as large as hen pheasants.  Their destroyer, a
small and pretty fox, was also singularly numerous; in the course of
the day we could not have seen less than forty or fifty.  They were
generally near their earths, but the dogs killed one.  When we returned
to the posta, we found two of the party returned who had been hunting
by themselves. They had killed a puma, and had found an ostrich's nest
with twenty-seven eggs in it.  Each of these is said to equal in weight
eleven hen's eggs; so that we obtained from this one nest as much food
as 297 hen's eggs would have given.

September 14th.--As the soldiers belonging to the next posta meant to
return, and we should together make a party of five, and all armed, I
determined not to wait for the expected troops.  My host, the
lieutenant, pressed me much to stop.  As he had been very obliging--not
only providing me with food, but lending me his private horses--I
wanted to make him some remuneration.  I asked my guide whether I might
do so, but he told me certainly not; that the only answer I should
receive, probably would be, "We have meat for the dogs in our country,
and therefore do not grudge it to a Christian." It must not be supposed
that the rank of lieutenant in such an army would at all prevent the
acceptance of payment: it was only the high sense of hospitality, which
every traveller is bound to acknowledge as nearly universal throughout
these provinces.  After galloping some leagues, we came to a low swampy
country, which extends for nearly eighty miles northward, as far as the
Sierra Tapalguen.  In some parts there were fine damp plains, covered
with grass, while others had a soft, black, and peaty soil. There were
also many extensive but shallow lakes, and large beds of reeds.  The
country on the whole resembled the better parts of the Cambridgeshire
fens.  At night we had some difficulty in finding amidst the swamps, a
dry place for our bivouac.

September 15th.--Rose very early in the morning and shortly after
passed the posta where the Indians had murdered the five soldiers.  The
officer had eighteen chuzo wounds in his body.  By the middle of the
day, after a hard gallop, we reached the fifth posta: on account of
some difficulty in procuring horses we stayed there the night.  As this
point was the most exposed on the whole line, twenty-one soldiers were
stationed here; at sunset they returned from hunting, bringing with
them seven deer, three ostriches, and many armadilloes and partridges.
When riding through the country, it is a common practice to set fire to
the plain; and hence at night, as on this occasion, the horizon was
illuminated in several places by brilliant conflagrations. This is done
partly for the sake of puzzling any stray Indians, but chiefly for
improving the pasture.  In grassy plains unoccupied by the larger
ruminating quadrupeds, it seems necessary to remove the superfluous
vegetation by fire, so as to render the new year's growth serviceable.

The rancho at this place did not boast even of a roof, but merely
consisted of a ring of thistle-stalks, to break the force of the wind.
It was situated on the borders of an extensive but shallow lake,
swarming with wild fowl, among which the black-necked swan was
conspicuous.

The kind of plover, which appears as if mounted on stilts (Himantopus
nigricollis), is here common in flocks of considerable size.  It has
been wrongfully accused of inelegance; when wading about in shallow
water, which is its favourite resort, its gait is far from awkward.
These birds in a flock utter a noise, that singularly resembles the cry
of a pack of small dogs in full chase: waking in the night, I have more
than once been for a moment startled at the distant sound.  The
teru-tero (Vanellus cayanus) is another bird, which often disturbs the
stillness of the night.  In appearance and habits it resembles in many
respects our peewits; its wings, however, are armed with sharp spurs,
like those on the legs of the common cock.  As our peewit takes its
name from the sound of its voice, so does the teru-tero. While riding
over the grassy plains, one is constantly pursued by these birds, which
appear to hate mankind, and I am sure deserve to be hated for their
never-ceasing, unvaried, harsh screams.  To the sportsman they are most
annoying, by telling every other bird and animal of his approach: to
the traveller in the country, they may possibly, as Molina says, do
good, by warning him of the midnight robber.  During the breeding
season, they attempt, like our peewits, by feigning to be wounded, to
draw away from their nests dogs and other enemies.  The eggs of this
bird are esteemed a great delicacy.

September 16th.--To the seventh posta at the foot of the Sierra
Tapalguen.  The country was quite level, with a coarse herbage and a
soft peaty soil.  The hovel was here remarkably neat, the posts and
rafters being made of about a dozen dry thistle-stalks bound together
with thongs of hide; and by the support of these Ionic-like columns,
the roof and sides were thatched with reeds.  We were here told a fact,
which I would not have credited, if I had not had partly ocular proof
of it; namely, that, during the previous night hail as large as small
apples, and extremely hard, had fallen with such violence, as to kill
the greater number of the wild animals.  One of the men had already
found thirteen deer (Cervus campestris) lying dead, and I saw their
_fresh_ hides; another of the party, a few minutes after my arrival
brought in seven more.  Now I well know, that one man without dogs
could hardly have killed seven deer in a week. The men believed they
had seen about fifteen ostriches (part of one of which we had for
dinner); and they said that several were running about evidently blind
in one eye. Numbers of smaller birds, as ducks, hawks, and partridges,
were killed.  I saw one of the latter with a black mark on its back, as
if it had been struck with a paving-stone.  A fence of thistle-stalks
round the hovel was nearly broken down, and my informer, putting his
head out to see what was the matter, received a severe cut, and now
wore a bandage. The storm was said to have been of limited extent: we
certainly saw from our last night's bivouac a dense cloud and lightning
in this direction.  It is marvellous how such strong animals as deer
could thus have been killed; but I have no doubt, from the evidence I
have given, that the story is not in the least exaggerated.  I am glad,
however, to have its credibility supported by the Jesuit Dobrizhoffen,
[4] who, speaking of a country much to the northward, says, hail fell
of an enormous size and killed vast numbers of cattle: the Indians
hence called the place _Lalegraicavalca_, meaning "the little white
things." Dr. Malcolmson, also, informs me that he witnessed in 1831 in
India, a hail-storm, which killed numbers of large birds and much
injured the cattle. These hailstones were flat, and one was ten inches
in circumference, and another weighed two ounces.  They ploughed up a
gravel-walk like musket-balls, and passed through glass-windows, making
round holes, but not cracking them.

Having finished our dinner, of hail-stricken meat, we crossed the
Sierra Tapalguen; a low range of hills, a few hundred feet in height,
which commences at Cape Corrientes. The rock in this part is pure
quartz; further eastward I understand it is granitic.  The hills are of
a remarkable form; they consist of flat patches of table-land,
surrounded by low perpendicular cliffs, like the outliers of a
sedimentary deposit.  The hill which I ascended was very small, not
above a couple of hundred yards in diameter; but I saw others larger.
One which goes by the name of the "Corral," is said to be two or three
miles in diameter, and encompassed by perpendicular cliffs, between
thirty and forty feet high, excepting at one spot, where the entrance
lies.  Falconer [5] gives a curious account of the Indians driving
troops of wild horses into it, and then by guarding the entrance,
keeping them secure.  I have never heard of any other instance of
table-land in a formation of quartz, and which, in the hill I examined,
had neither cleavage nor stratification.  I was told that the rock of
the "Corral" was white, and would strike fire.

We did not reach the posta on the Rio Tapalguen till after it was dark.
At supper, from something which was said, I was suddenly struck with
horror at thinking that I was eating one of the favourite dishes of the
country namely, a half-formed calf, long before its proper time of
birth.  It turned out to be Puma; the meat is very white and remarkably
like veal in taste.  Dr. Shaw was laughed at for stating that "the
flesh of the lion is in great esteem having no small affinity with
veal, both in colour, taste, and flavour." Such certainly is the case
with the Puma. The Gauchos differ in their opinion, whether the Jaguar
is good eating, but are unanimous in saying that cat is excellent.

September 17th.--We followed the course of the Rio Tapalguen, through a
very fertile country, to the ninth posta.  Tapalguen, itself, or the
town of Tapalguen, if it may be so called, consists of a perfectly
level plain, studded over, as far as the eye can reach, with the toldos
or oven-shaped huts of the Indians.  The families of the friendly
Indians, who were fighting on the side of Rosas, resided here. We met
and passed many young Indian women, riding by two or three together on
the same horse: they, as well as many of the young men, were strikingly
handsome,--their fine ruddy complexions being the picture of health.
Besides the toldos, there were three ranchos; one inhabited by the
Commandant, and the two others by Spaniards with small shops.

We were here able to buy some biscuit.  I had now been several days
without tasting anything besides meat: I did not at all dislike this
new regimen; but I felt as if it would only have agreed with me with
hard exercise.  I have heard that patients in England, when desired to
confine themselves exclusively to an animal diet, even with the hope of
life before their eyes, have hardly been able to endure it.  Yet the
Gaucho in the Pampas, for months together, touches nothing but beef.
But they eat, I observe, a very large proportion of fat, which is of a
less animalized nature; and they particularly dislike dry meat, such as
that of the Agouti. Dr. Richardson [6] also, has remarked, "that when
people have fed for a long time solely upon lean animal food, the
desire for fat becomes so insatiable, that they can consume a large
quantity of unmixed and even oily fat without nausea:" this appears to
me a curious physiological fact. It is, perhaps, from their meat
regimen that the Gauchos, like other carnivorous animals, can abstain
long from food. I was told that at Tandeel, some troops voluntarily
pursued a party of Indians for three days, without eating or drinking.

We saw in the shops many articles, such as horsecloths, belts, and
garters, woven by the Indian women.  The patterns were very pretty, and
the colours brilliant; the workmanship of the garters was so good that
an English merchant at Buenos Ayres maintained they must have been
manufactured in England, till he found the tassels had been fastened by
split sinew.

September 18th.--We had a very long ride this day.  At the twelfth
posta, which is seven leagues south of the Rio Salado, we came to the
first estancia with cattle and white women.  Afterwards we had to ride
for many miles through a country flooded with water above our horses'
knees.  By crossing the stirrups, and riding Arab-like with our legs
bent up, we contrived to keep tolerably dry.  It was nearly dark when
we arrived at the Salado; the stream was deep, and about forty yards
wide; in summer, however, its bed becomes almost dry, and the little
remaining water nearly as salt as that of the sea.  We slept at one of
the great estancias of General Rosas.  It was fortified, and of such an
extent, that arriving in the dark I thought it was a town and fortress.
In the morning we saw immense herds of cattle, the general here having
seventy-four square leagues of land.  Formerly nearly three hundred men
were employed about this estate, and they defied all the attacks of the
Indians.

September 19th.--Passed the Guardia del Monte.  This is a nice
scattered little town, with many gardens, full of peach and quince
trees.  The plain here looked like that around Buenos Ayres; the turf
being short and bright green, with beds of clover and thistles, and
with bizcacha holes. I was very much struck with the marked change in
the aspect of the country after having crossed the Salado.  From a
coarse herbage we passed on to a carpet of fine green verdure. I at
first attributed this to some change in the nature of the soil, but the
inhabitants assured me that here, as well as in Banda Oriental, where
there is as great a difference between the country round Monte Video
and the thinly-inhabited savannahs of Colonia, the whole was to be
attributed to the manuring and grazing of the cattle.  Exactly the same
fact has been observed in the prairies [7] of North America, where
coarse grass, between five and six feet high, when grazed by cattle,
changes into common pasture land.  I am not botanist enough to say
whether the change here is owing to the introduction of new species, to
the altered growth of the same, or to a difference in their
proportional numbers.  Azara has also observed with astonishment this
change: he is likewise much perplexed by the immediate appearance of
plants not occurring in the neighbourhood, on the borders of any track
that leads to a newly-constructed hovel.  In another part he says, [8]
"ces chevaux (sauvages) ont la manie de preferer les chemins, et le
bord des routes pour deposer leurs excremens, dont on trouve des
monceaux dans ces endroits." Does this not partly explain the
circumstance?  We thus have lines of richly manured land serving as
channels of communication across wide districts.

Near the Guardia we find the southern limit of two European plants, now
become extraordinarily common.  The fennel in great profusion covers
the ditch-banks in the neighbourhood of Buenos Ayres, Monte Video, and
other towns. But the cardoon (Cynara cardunculus) has a far wider
range: [9] it occurs in these latitudes on both sides of the,
Cordillera, across the continent.  I saw it in unfrequented spots in
Chile, Entre Rios, and Banda Oriental.  In the latter country alone,
very many (probably several hundred) square miles are covered by one
mass of these prickly plants, and are impenetrable by man or beast.
Over the undulating plains, where these great beds occur, nothing else
can now live.  Before their introduction, however, the surface must
have supported, as in other parts, a rank herbage.  I doubt whether any
case is on record of an invasion on so grand a scale of one plant over
the aborigines.  As I have already said, I nowhere saw the cardoon
south of the Salado; but it is probable that in proportion as that
country becomes inhabited, the cardoon will extend its limits.  The
case is different with the giant thistle (with variegated leaves) of
the Pampas, for I met with it in the valley of the Sauce. According to
the principles so well laid down by Mr. Lyell, few countries have
undergone more remarkable changes, since the year 1535, when the first
colonist of La Plata landed with seventy-two horses.  The countless
herds of horses, cattle, and sheep, not only have altered the whole
aspect of the vegetation, but they have almost banished the guanaco,
deer and ostrich.  Numberless other changes must likewise have taken
place; the wild pig in some parts probably replaces the peccari; packs
of wild dogs may be heard howling on the wooded banks of the
less-frequented streams; and the common cat, altered into a large and
fierce animal, inhabits rocky hills.  As M. d'Orbigny has remarked, the
increase in numbers of the carrion-vulture, since the introduction of
the domestic animals, must have been infinitely great; and we have
given reasons for believing that they have extended their southern
range.  No doubt many plants, besides the cardoon and fennel, are
naturalized; thus the islands near the mouth of the Parana, are thickly
clothed with peach and orange trees, springing from seeds carried there
by the waters of the river.

While changing horses at the Guardia several people questioned us much
about the army,--I never saw anything like the enthusiasm for Rosas,
and for the success of the "most just of all wars, because against
barbarians." This expression, it must be confessed, is very natural,
for till lately, neither man, woman nor horse, was safe from the
attacks of the Indians.  We had a long day's ride over the same rich
green plain, abounding with various flocks, and with here and there a
solitary estancia, and its one _ombu_ tree. In the evening it rained
heavily: on arriving at a posthouse we were told by the owner, that if
we had not a regular passport we must pass on, for there were so many
robbers he would trust no one.  When he read, however, my passport,
which began with "El Naturalista Don Carlos," his respect and civility
were as unbounded as his suspicions had been before.  What a naturalist
might be, neither he nor his countrymen, I suspect, had any idea; but
probably my title lost nothing of its value from that cause.

September 20th.--We arrived by the middle of the day at Buenos Ayres.
The outskirts of the city looked quite pretty, with the agave hedges,
and groves of olive, peach and willow trees, all just throwing out
their fresh green leaves.  I rode to the house of Mr. Lumb, an English
merchant, to whose kindness and hospitality, during my stay in the
country, I was greatly indebted.

The city of Buenos Ayres is large; [10] and I should think one of the
most regular in the world.  Every street is at right angles to the one
it crosses, and the parallel ones being equidistant, the houses are
collected into solid squares of equal dimensions, which are called
quadras.  On the other hand, the houses themselves are hollow squares;
all the rooms opening into a neat little courtyard.  They are generally
only one story high, with flat roofs, which are fitted with seats and
are much frequented by the inhabitants in summer.  In the centre of the
town is the Plaza, where the public offices, fortress, cathedral, etc.,
stand.  Here also, the old viceroys, before the revolution, had their
palaces.  The general assemblage of buildings possesses considerable
architectural beauty, although none individually can boast of any.

The great _corral_, where the animals are kept for slaughter to supply
food to this beef-eating population, is one of the spectacles best
worth seeing.  The strength of the horse as compared to that of the
bullock is quite astonishing: a man on horseback having thrown his lazo
round the horns of a beast, can drag it anywhere he chooses.  The
animal ploughing up the ground with outstretched legs, in vain efforts
to resist the force, generally dashes at full speed to one side; but
the horse immediately turning to receive the shock, stands so firmly
that the bullock is almost thrown down, and it is surprising that their
necks are not broken. The struggle is not, however, one of fair
strength; the horse's girth being matched against the bullock's
extended neck.  In a similar manner a man can hold the wildest horse,
if caught with the lazo, just behind the ears.  When the bullock has
been dragged to the spot where it is to be slaughtered, the matador
with great caution cuts the hamstrings. Then is given the death bellow;
a noise more expressive of fierce agony than any I know.  I have often
distinguished it from a long distance, and have always known that the
struggle was then drawing to a close.  The whole sight is horrible and
revolting: the ground is almost made of bones; and the horses and
riders are drenched with gore.

[1] I call these thistle-stalks for the want of a more correct name.  I
believe it is a species of Eryngium.

[2] Travels in Africa, p. 233.

[3] Two species of Tinamus and Eudromia elegans of A. d'Orbigny, which
can only be called a partridge with regard to its habits.

[4] History of the Abipones, vol. ii. p. 6.

[5] Falconer's Patagonia, p. 70.

[6] Fauna Boreali-Americana, vol. i. p. 35.

[7] See Mr. Atwater's account of the Prairies, in Silliman's N. A.
Journal, vol. i. p. 117.

[8] Azara's Voyages, vol. i. p. 373.

[9] M. A. d'Orbigny (vol. i. p. 474) says that the cardoon and
artichoke are both found wild.  Dr. Hooker (Botanical Magazine, vol.
iv. p. 2862), has described a variety of the Cynara from this part of
South America under the name of inermis.  He states that botanists are
now generally agreed that the cardoon and the artichoke are varieties
of one plant. I may add, that an intelligent farmer assured me that he
had observed in a deserted garden some artichokes changing into the
common cardoon.  Dr. Hooker believes that Head's vivid description of
the thistle of the Pampas applies to the cardoon, but this is a
mistake.  Captain Head referred to the plant, which I have mentioned a
few lines lower down, under the title of giant thistle.  Whether it is
a true thistle I do not know; but it is quite different from the
cardoon; and more like a thistle properly so called.

[10] It is said to contain 60,000 inhabitants.  Monte Video, the second
town of importance on the banks of the Plata, has 15,000.



CHAPTER VII

BUENOS AYRES AND ST. FE

Excursion to St. Fe--Thistle Beds--Habits of the Bizcacha--Little
Owl--Saline Streams--Level Plain--Mastodon--St. Fe--Change in
Landscape--Geology--Tooth of extinct Horse--Relation of the Fossil and
recent Quadrupeds of North and South America--Effects of a great
Drought--Parana--Habits of the Jaguar--Scissor-beak--Kingfisher,
Parrot, and Scissor-tail--Revolution--Buenos Ayres State of Government.


SEPTEMBER  27th.--In the evening I set out on an excursion to St. Fe,
which is situated nearly three hundred English miles from Buenos Ayres,
on the banks of the Parana.  The roads in the neighbourhood of the city
after the rainy weather, were extraordinarily bad.  I should never have
thought it possible for a bullock waggon to have crawled along: as it
was, they scarcely went at the rate of a mile an hour, and a man was
kept ahead, to survey the best line for making the attempt.  The
bullocks were terribly jaded: it is a great mistake to suppose that
with improved roads, and an accelerated rate of travelling, the
sufferings of the animals increase in the same proportion.  We passed a
train of waggons and a troop of beasts on their road to Mendoza.  The
distance is about 580 geographical miles, and the journey is generally
performed in fifty days.  These waggons are very long, narrow, and
thatched with reeds; they have only two wheels, the diameter of which
in some cases is as much as ten feet.  Each is drawn by six bullocks,
which are urged on by a goad at least twenty feet long: this is
suspended from within the roof; for the wheel bullocks a smaller one is
kept; and for the intermediate pair, a point projects at right angles
from the middle of the long one.

The whole apparatus looked like some implement of war.

September 28th.--We passed the small town of Luxan where there is a
wooden bridge over the river--a most unusual convenience in this
country.  We passed also Areco. The plains appeared level, but were not
so in fact; for in various places the horizon was distant.  The
estancias are here wide apart; for there is little good pasture, owing
to the land being covered by beds either of an acrid clover, or of the
great thistle.  The latter, well known from the animated description
given by Sir F. Head, were at this time of the year two-thirds grown;
in some parts they were as high as the horse's back, but in others they
had not yet sprung up, and the ground was bare and dusty as on a
turnpike-road.  The clumps were of the most brilliant green, and they
made a pleasing miniature-likeness of broken forest land.  When the
thistles are full grown, the great beds are impenetrable, except by a
few tracts, as intricate as those in a labyrinth.  These are only known
to the robbers, who at this season inhabit them, and sally forth at
night to rob and cut throats with impunity.  Upon asking at a house
whether robbers were numerous, I was answered, "The thistles are not up
yet;"--the meaning of which reply was not at first very obvious. There
is little interest in passing over these tracts, for they are inhabited
by few animals or birds, excepting the bizcacha and its friend the
little owl.

The bizcacha [1] is well known to form a prominent feature in the
zoology of the Pampas.  It is found as far south as the Rio Negro, in
lat. 41 degs., but not beyond.  It cannot, like the agouti, subsist on
the gravelly and desert plains of Patagonia, but prefers a clayey or
sandy soil, which produces a different and more abundant vegetation.
Near Mendoza, at the foot of the Cordillera, it occurs in close
neighbourhood with the allied alpine species.  It is a very curious
circumstance in its geographical distribution, that it has never been
seen, fortunately for the inhabitants of Banda Oriental, to the
eastward of the river Uruguay: yet in this province there are plains
which appear admirably adapted to its habits. The Uruguay has formed an
insuperable obstacle to its migration: although the broader barrier of
the Parana has been passed, and the bizcacha is common in Entre Rios,
the province between these two great rivers.  Near Buenos Ayres these
animals are exceedingly common.  Their most favourite resort appears to
be those parts of the plain which during one-half of the year are
covered with giant thistles, to the exclusion of other plants.  The
Gauchos affirm that it lives on roots; which, from the great strength
of its gnawing teeth, and the kind of places frequented by it, seems
probable. In the evening the bizcachas come out in numbers, and quietly
sit at the mouths of their burrows on their haunches.  At such times
they are very tame, and a man on horseback passing by seems only to
present an object for their grave contemplation.  They run very
awkwardly, and when running out of danger, from their elevated tails
and short front legs much resemble great rats.  Their flesh, when
cooked, is very white and good, but it is seldom used.

The bizcacha has one very singular habit; namely, dragging every hard
object to the mouth of its burrow: around each group of holes many
bones of cattle, stones, thistle-stalks, hard lumps of earth, dry dung,
etc., are collected into an irregular heap, which frequently amounts to
as much as a wheelbarrow would contain.  I was credibly informed that a
gentleman, when riding on a dark night, dropped his watch; he returned
in the morning, and by searching the neighbourhood of every bizcacha
hole on the line of road, as he expected, he soon found it.  This habit
of picking up whatever may be lying on the ground anywhere near its
habitation, must cost much trouble.  For what purpose it is done, I am
quite unable to form even the most remote conjecture: it cannot be for
defence, because the rubbish is chiefly placed above the mouth of the
burrow, which enters the ground at a very small inclination.  No doubt
there must exist some good reason; but the inhabitants of the country
are quite ignorant of it.  The only fact which I know analogous to it,
is the habit of that extraordinary Australian bird, the Calodera
maculata, which makes an elegant vaulted passage of twigs for playing
in, and which collects near the spot, land and sea-shells, bones and
the feathers of birds, especially brightly coloured ones.  Mr. Gould,
who has described these facts, informs me, that the natives, when they
lose any hard object, search the playing passages, and he has known a
tobacco-pipe thus recovered.

The little owl (Athene cunicularia), which has been so often mentioned,
on the plains of Buenos Ayres exclusively inhabits the holes of the
bizcacha; but in Banda Oriental it is its own workman.  During the open
day, but more especially in the evening, these birds may be seen in
every direction standing frequently by pairs on the hillock near their
burrows.  If disturbed they either enter the hole, or, uttering a
shrill harsh cry, move with a remarkably undulatory flight to a short
distance, and then turning round, steadily gaze at their pursuer.
Occasionally in the evening they may be heard hooting.  I found in the
stomachs of two which I opened the remains of mice, and I one day saw a
small snake killed and carried away.  It is said that snakes are their
common prey during the daytime.  I may here mention, as showing on what
various kinds of food owls subsist, that a species killed among the
islets of the Chonos Archipelago, had its stomach full of good-sized
crabs.  In India [2] there is a fishing genus of owls, which likewise
catches crabs.

In the evening we crossed the Rio Arrecife on a simple raft made of
barrels lashed together, and slept at the post-house on the other side.
I this day paid horse-hire for thirty-one leagues; and although the sun
was glaring hot I was but little fatigued.  When Captain Head talks of
riding fifty leagues a day, I do not imagine the distance is equal to
150 English miles.  At all events, the thirty-one leagues was only 76
miles in a straight line, and in an open country I should think four
additional miles for turnings would be a sufficient allowance.

29th and 30th.--We continued to ride over plains of the same character.
At San Nicolas I first saw the noble river of the Parana. At the foot
of the cliff on which the town stands, some large vessels were at
anchor.  Before arriving at Rozario, we crossed the Saladillo, a stream
of fine clear running water, but too saline to drink.  Rozario is a
large town built on a dead level plain, which forms a cliff about sixty
feet high over the Parana.  The river here is very broad, with many
islands, which are low and wooded, as is also the opposite shore. The
view would resemble that of a great lake, if it were not for the
linear-shaped islets, which alone give the idea of running water.  The
cliffs are the most picturesque part; sometimes they are absolutely
perpendicular, and of a red colour; at other times in large broken
masses, covered with cacti and mimosa-trees.  The real grandeur,
however, of an immense river like this, is derived from reflecting how
important a means of communication and commerce it forms between one
nation and another; to what a distance it travels, and from how vast a
territory it drains the great body of fresh water which flows past your
feet.

For many leagues north and south of San Nicolas and Rozario, the
country is really level.  Scarcely anything which travellers have
written about its extreme flatness, can be considered as exaggeration.
Yet I could never find a spot where, by slowly turning round, objects
were not seen at greater distances in some directions than in others;
and this manifestly proves inequality in the plain.  At sea, a person's
eye being six feet above the surface of the water, his horizon is two
miles and four-fifths distant.  In like manner, the more level the
plain, the more nearly does the horizon approach within these narrow
limits; and this, in my opinion, entirely destroys that grandeur which
one would have imagined that a vast level plain would have possessed.

October 1st.--We started by moonlight and arrived at the Rio Tercero by
sunrise.  The river is also called the Saladillo, and it deserves the
name, for the water is brackish. I stayed here the greater part of the
day, searching for fossil bones.  Besides a perfect tooth of the
Toxodon, and many scattered bones, I found two immense skeletons near
each other, projecting in bold relief from the perpendicular cliff of
the Parana.  They were, however, so completely decayed, that I could
only bring away small fragments of one of the great molar teeth; but
these are sufficient to show that the remains belonged to a Mastodon,
probably to the same species with that, which formerly must have
inhabited the Cordillera in Upper Peru in such great numbers.  The men
who took me in the canoe, said they had long known of these skeletons,
and had often wondered how they had got there: the necessity of a
theory being felt, they came to the conclusion that, like the bizcacha,
the mastodon was formerly a burrowing animal!  In the evening we rode
another stage, and crossed the Monge, another brackish stream, bearing
the dregs of the washings of the Pampas.

October 2nd.--We passed through Corunda, which, from the luxuriance of
its gardens, was one of the prettiest villages I saw.  From this point
to St. Fe the road is not very safe.  The western side of the Parana
northward, ceases to be inhabited; and hence the Indians sometimes come
down thus far, and waylay travellers.  The nature of the country also
favours this, for instead of a grassy plain, there is an open woodland,
composed of low prickly mimosas.  We passed some houses that had been
ransacked and since deserted; we saw also a spectacle, which my guides
viewed with high satisfaction; it was the skeleton of an Indian with
the dried skin hanging on the bones, suspended to the branch of a tree.

In the morning we arrived at St. Fe. I was surprised to observe how
great a change of climate a difference of only three degrees of
latitude between this place and Buenos Ayres had caused.  This was
evident from the dress and complexion of the men--from the increased
size of the ombu-trees--the number of new cacti and other plants--and
especially from the birds.  In the course of an hour I remarked
half-a-dozen birds, which I had never seen at Buenos Ayres. Considering
that there is no natural boundary between the two places, and that the
character of the country is nearly similar, the difference was much
greater than I should have expected.

October  3rd and 4th.--I was confined for these two days to my bed by a
headache.  A good-natured old woman, who attended me, wished me to try
many odd remedies.  A common practice is, to bind an orange-leaf or a
bit of black plaster to each temple: and a still more general plan is,
to split a bean into halves, moisten them, and place one on each
temple, where they will easily adhere.  It is not thought proper ever
to remove the beans or plaster, but to allow them to drop off, and
sometimes, if a man, with patches on his head, is asked, what is the
matter? he will answer, "I had a headache the day before yesterday."
Many of the remedies used by the people of the country are ludicrously
strange, but too disgusting to be mentioned.  One of the least nasty is
to kill and cut open two puppies and bind them on each side of a broken
limb.  Little hairless dogs are in great request to sleep at the feet
of invalids.

St. Fe is a quiet little town, and is kept clean and in good order. The
governor, Lopez, was a common soldier at the time of the revolution;
but has now been seventeen years in power.  This stability of
government is owing to his tyrannical habits; for tyranny seems as yet
better adapted to these countries than republicanism.  The governor's
favourite occupation is hunting Indians: a short time since he
slaughtered forty-eight, and sold the children at the rate of three or
four pounds apiece.

October 5th.--We crossed the Parana to St. Fe Bajada, a town on the
opposite shore.  The passage took some hours, as the river here
consisted of a labyrinth of small streams, separated by low wooded
islands.  I had a letter of introduction to an old Catalonian Spaniard,
who treated me with the most uncommon hospitality.  The Bajada is the
capital of Entre Rios.  In 1825 the town contained 6000 inhabitants,
and the province 30,000; yet, few as the inhabitants are, no province
has suffered more from bloody and desperate revolutions.  They boast
here of representatives, ministers, a standing army, and governors: so
it is no wonder that they have their revolutions.  At some future day
this must be one of the richest countries of La Plata.  The soil is
varied and productive; and its almost insular form gives it two grand
lines of communication by the rivers Parana and Uruguay.


I was delayed here five days, and employed myself in examining the
geology of the surrounding country, which was very interesting.  We
here see at the bottom of the cliffs, beds containing sharks' teeth and
sea-shells of extinct species, passing above into an indurated marl,
and from that into the red clayey earth of the Pampas, with its
calcareous concretions and the bones of terrestrial quadrupeds.  This
vertical section clearly tells us of a large bay of pure salt-water,
gradually encroached on, and at last converted into the bed of a muddy
estuary, into which floating carcasses were swept.  At Punta Gorda, in
Banda Oriental, I found an alternation of the Pampaean estuary deposit,
with a limestone containing some of the same extinct sea-shells; and
this shows either a change in the former currents, or more probably an
oscillation of level in the bottom of the ancient estuary.  Until
lately, my reasons for considering the Pampaean formation to be an
estuary deposit were, its general appearance, its position at the mouth
of the existing great river the Plata, and the presence of so many
bones of terrestrial quadrupeds: but now Professor Ehrenberg has had
the kindness to examine for me a little of the red earth, taken from
low down in the deposit, close to the skeletons of the mastodon, and he
finds in it many infusoria, partly salt-water and partly fresh-water
forms, with the latter rather preponderating; and therefore, as he
remarks, the water must have been brackish.  M. A. d'Orbigny found on
the banks of the Parana, at the height of a hundred feet, great beds of
an estuary shell, now living a hundred miles lower down nearer the sea;
and I found similar shells at a less height on the banks of the
Uruguay; this shows that just before the Pampas was slowly elevated
into dry land, the water covering it was brackish.  Below Buenos Ayres
there are upraised beds of sea-shells of existing species, which also
proves that the period of elevation of the Pampas was within the recent
period.

In the Pampaean deposit at the Bajada I found the osseous armour of a
gigantic armadillo-like animal, the inside of which, when the earth was
removed, was like a great cauldron; I found also teeth of the Toxodon
and Mastodon, and one tooth of a Horse, in the same stained and decayed
state.  This latter tooth greatly interested me, [3] and I took
scrupulous care in ascertaining that it had been embedded
contemporaneously with the other remains; for I was not then aware that
amongst the fossils from Bahia Blanca there was a horse's tooth hidden
in the matrix: nor was it then known with certainty that the remains of
horses are common in North America.  Mr. Lyell has lately brought from
the United States a tooth of a horse; and it is an interesting fact,
that Professor Owen could find in no species, either fossil or recent,
a slight but peculiar curvature characterizing it, until he thought of
comparing it with my specimen found here: he has named this American
horse Equus curvidens.  Certainly it is a marvellous fact in the
history of the Mammalia, that in South America a native horse should
have lived and disappeared, to be succeeded in after-ages by the
countless herds descended from the few introduced with the Spanish
colonists!

The existence in South America of a fossil horse, of the mastodon,
possibly of an elephant, [4]  and of a hollow-horned ruminant,
discovered by MM. Lund and Clausen in the caves of Brazil, are highly
interesting facts with respect to the geographical distribution of
animals.  At the present time, if we divide America, not by the Isthmus
of Panama, but by the southern part of Mexico [5] in lat. 20 degs.,
where the great table-land presents an obstacle to the migration of
species, by affecting the climate, and by forming, with the exception
of some valleys and of a fringe of low land on the coast, a broad
barrier; we shall then have the two zoological provinces of North and
South America strongly contrasted with each other.  Some few species
alone have passed the barrier, and may be considered as wanderers from
the south, such as the puma, opossum, kinkajou, and peccari. South
America is characterized by possessing many peculiar gnawers, a family
of monkeys, the llama, peccari, tapir, opossums, and, especially,
several genera of Edentata, the order which includes the sloths,
ant-eaters, and armadilloes. North America, on the other hand, is
characterized (putting on one side a few wandering species) by numerous
peculiar gnawers, and by four genera (the ox, sheep, goat, and
antelope) of hollow-horned ruminants, of which great division South
America is not known to possess a single species. Formerly, but within
the period when most of the now existing shells were living, North
America possessed, besides hollow-horned ruminants, the elephant,
mastodon, horse, and three genera of Edentata, namely, the Megatherium,
Megalonyx, and Mylodon.  Within nearly this same period (as proved by
the shells at Bahia Blanca) South America possessed, as we have just
seen, a mastodon, horse, hollow-horned ruminant, and the same three
genera (as well as several others) of the Edentata.  Hence it is
evident that North and South America, in having within a late
geological period these several genera in common, were much more
closely related in the character of their terrestrial inhabitants than
they now are.  The more I reflect on this case, the more interesting it
appears: I know of no other instance where we can almost mark the
period and manner of the splitting up of one great region into two
well-characterized zoological provinces.  The geologist, who is fully
impressed with the vast oscillations of level which have affected the
earth's crust within late periods, will not fear to speculate on the
recent elevation of the Mexican platform, or, more probably, on the
recent submergence of land in the West Indian Archipelago, as the cause
of the present zoological separation of North and South America.  The
South American character of the West Indian mammals [6] seems to
indicate that this archipelago was formerly united to the southern
continent, and that it has subsequently been an area of subsidence.

When America, and especially North America, possessed its elephants,
mastodons, horse, and hollow-horned ruminants, it was much more closely
related in its zoological characters to the temperate parts of Europe
and Asia than it now is.  As the remains of these genera are found on
both sides of Behring's Straits [7] and on the plains of Siberia, we
are led to look to the north-western side of North America as the
former point of communication between the Old and so-called New World.
And as so many species, both living and extinct, of these same genera
inhabit and have inhabited the Old World, it seems most probable that
the North American elephants, mastodons, horse, and hollow-horned
ruminants migrated, on land since submerged near Behring's Straits,
from Siberia into North America, and thence, on land since submerged in
the West Indies, into South America, where for a time they mingled with
the forms characteristic of that southern continent, and have since
become extinct.


While travelling through the country, I received several vivid
descriptions of the effects of a late great drought; and the account of
this may throw some light on the cases where vast numbers of animals of
all kinds have been embedded together.  The period included between the
years 1827 and 1830 is called the "gran seco," or the great drought.
During this time so little rain fell, that the vegetation, even to the
thistles, failed; the brooks were dried up, and the whole country
assumed the appearance of a dusty high road.  This was especially the
case in the northern part of the province of Buenos Ayres and the
southern part of St. Fe.  Very great numbers of birds, wild animals,
cattle, and horses perished from the want of food and water.  A man
told me that the deer [8] used to come into his courtyard to the well,
which he had been obliged to dig to supply his own family with water;
and that the partridges had hardly strength to fly away when pursued.
The lowest estimation of the loss of cattle in the province of Buenos
Ayres alone, was taken at one million head.  A proprietor at San Pedro
had previously to these years 20,000 cattle; at the end not one
remained. San Pedro is situated in the middle of the finest country;
and even now abounds again with animals; yet during the latter part of
the "gran seco," live cattle were brought in vessels for the
consumption of the inhabitants. The animals roamed from their
estancias, and, wandering far southward, were mingled together in such
multitudes, that a government commission was sent from Buenos Ayres to
settle the disputes of the owners.  Sir Woodbine Parish informed me of
another and very curious source of dispute; the ground being so long
dry, such quantities of dust were blown about, that in this open
country the landmarks became obliterated, and people could not tell the
limits of their estates.

I was informed by an eye-witness that the cattle in herds of thousands
rushed into the Parana, and being exhausted by hunger they were unable
to crawl up the muddy banks, and thus were drowned.  The arm of the
river which runs by San Pedro was so full of putrid carcasses, that the
master of a vessel told me that the smell rendered it quite impassable.
Without doubt several hundred thousand animals thus perished in the
river: their bodies when putrid were seen floating down the stream; and
many in all probability were deposited in the estuary of the Plata. All
the small rivers became highly saline, and this caused the death of
vast numbers in particular spots; for when an animal drinks of such
water it does not recover.  Azara describes [9] the fury of the wild
horses on a similar occasion, rushing into the marshes, those which
arrived first being overwhelmed and crushed by those which followed. He
adds that more than once he has seen the carcasses of upwards of a
thousand wild horses thus destroyed.  I noticed that the smaller
streams in the Pampas were paved with a breccia of bones but this
probably is the effect of a gradual increase, rather than of the
destruction at any one period.  Subsequently to the drought of 1827 to
1832, a very rainy season followed which caused great floods.  Hence it
is almost certain that some thousands of the skeletons were buried by
the deposits of the very next year.  What would be the opinion of a
geologist, viewing such an enormous collection of bones, of all kinds
of animals and of all ages, thus embedded in one thick earthy mass?
Would he not attribute it to a flood having swept over the surface of
the land, rather than to the common order of things? [10]

October 12th.--I had intended to push my excursion further, but not
being quite well, I was compelled to return by a balandra, or
one-masted vessel of about a hundred tons' burden, which was bound to
Buenos Ayres.  As the weather was not fair, we moored early in the day
to a branch of a tree on one of the islands.  The Parana is full of
islands, which undergo a constant round of decay and renovation. In the
memory of the master several large ones had disappeared, and others
again had been formed and protected by vegetation.  They are composed
of muddy sand, without even the smallest pebble, and were then about
four feet above the level of the river; but during the periodical
floods they are inundated.  They all present one character; numerous
willows and a few other trees are bound together by a great variety of
creeping plants, thus forming a thick jungle. These thickets afford a
retreat for capybaras and jaguars. The fear of the latter animal quite
destroyed all pleasure in scrambling through the woods.  This evening I
had not proceeded a hundred yards, before finding indubitable signs of
the recent presence of the tiger, I was obliged to come back.  On every
island there were tracks; and as on the former excursion "el rastro de
los Indios" had been the subject of conversation, so in this was "el
rastro del tigre." The wooded banks of the great rivers appear to be
the favourite haunts of the jaguar; but south of the Plata, I was told
that they frequented the reeds bordering lakes: wherever they are, they
seem to require water.  Their common prey is the capybara, so that it
is generally said, where capybaras are numerous there is little danger
from the jaguar.  Falconer states that near the southern side of the
mouth of the Plata there are many jaguars, and that they chiefly live
on fish; this account I have heard repeated.  On the Parana they have
killed many wood-cutters, and have even entered vessels at night. There
is a man now living in the Bajada, who, coming up from below when it
was dark, was seized on the deck; he escaped, however, with the loss of
the use of one arm.  When the floods drive these animals from the
islands, they are most dangerous.  I was told that a few years since a
very large one found its way into a church at St. Fe: two padres
entering one after the other were killed, and a third, who came to see
what was the matter, escaped with difficulty.  The beast was destroyed
by being shot from a corner of the building which was unroofed. They
commit also at these times great ravages among cattle and horses.  It
is said that they kill their prey by breaking their necks.  If driven
from the carcass, they seldom return to it.  The Gauchos say that the
jaguar, when wandering about at night, is much tormented by the foxes
yelping as they follow him.  This is a curious coincidence with the
fact which is generally affirmed of the jackals accompanying, in a
similarly officious manner, the East Indian tiger.  The jaguar is a
noisy animal, roaring much by night, and especially before bad weather.

One day, when hunting on the banks of the Uruguay, I was shown certain
trees, to which these animals constantly recur for the purpose, as it
is said, of sharpening their claws.  I saw three well-known trees; in
front, the bark was worn smooth, as if by the breast of the animal, and
on each side there were deep scratches, or rather grooves, extending in
an oblique line, nearly a yard in length.  The scars were of different
ages.  A common method of ascertaining whether a jaguar is in the
neighbourhood is to examine these trees.  I imagine this habit of the
jaguar is exactly similar to one which may any day be seen in the
common cat, as with outstretched legs and exserted claws it scrapes the
leg of a chair; and I have heard of young fruit-trees in an orchard in
England having been thus much injured. Some such habit must also be
common to the puma, for on the bare hard soil of Patagonia I have
frequently seen scores so deep that no other animal could have made
them.  The object of this practice is, I believe, to tear off the
ragged points of their claws, and not, as the Gauchos think, to sharpen
them.  The jaguar is killed, without much difficulty, by the aid of
dogs baying and driving him up a tree, where he is despatched with
bullets.

Owing to bad weather we remained two days at our moorings. Our only
amusement was catching fish for our dinner: there were several kinds,
and all good eating.  A fish called the "armado" (a Silurus) is
remarkable from a harsh grating noise which it makes when caught by
hook and line, and which can be distinctly heard when the fish is
beneath the water.  This same fish has the power of firmly catching
hold of any object, such as the blade of an oar or the fishing-line,
with the strong spine both of its pectoral and dorsal fin.  In the
evening the weather was quite tropical, the thermometer standing at 79
degs.  Numbers of fireflies were hovering about, and the musquitoes
were very troublesome. I exposed my hand for five minutes, and it was
soon black with them; I do not suppose there could have been less than
fifty, all busy sucking.

October 15th.--We got under way and passed Punta Gorda, where there is
a colony of tame Indians from the province of Missiones.  We sailed
rapidly down the current, but before sunset, from a silly fear of bad
weather, we brought-to in a narrow arm of the river.  I took the boat
and rowed some distance up this creek.  It was very narrow, winding,
and deep; on each side a wall thirty or forty feet high, formed by
trees intwined with creepers, gave to the canal a singularly gloomy
appearance.  I here saw a very extraordinary bird, called the
Scissor-beak (Rhynchops nigra).  It has short legs, web feet, extremely
long-pointed wings, and is of about the size of a tern.  The beak is
flattened laterally, that is, in a plane at right angles to that of a
spoonbill or duck.  It is as flat and elastic as an ivory paper-cutter,
and the lower mandible, differing from every other bird, is an inch and
a half longer than the upper.  In a lake near Maldonado, from which the
water had been nearly drained, and which, in consequence, swarmed with
small fry, I saw several of these birds, generally in small flocks,
flying rapidly backwards and forwards close to the surface of the lake.
They kept their bills wide open, and the lower mandible half buried in
the water.  Thus skimming the surface, they ploughed it in their
course: the water was quite smooth, and it formed a most curious
spectacle to behold a flock, each bird leaving its narrow wake on the
mirror-like surface.  In their flight they frequently twist about with
extreme quickness, and dexterously manage with their projecting lower
mandible to plough up small fish, which are secured by the upper and
shorter half of their scissor-like

[picture]

bills.  This fact I repeatedly saw, as, like swallows, they continued
to fly backwards and forwards close before me. Occasionally when
leaving the surface of the water their flight was wild, irregular, and
rapid; they then uttered loud harsh cries.  When these birds are
fishing, the advantage of the long primary feathers of their wings, in
keeping them dry, is very evident.  When thus employed, their forms
resemble the symbol by which many artists represent marine birds. Their
tails are much used in steering their irregular course.

These birds are common far inland along the course of the Rio Parana;
it is said that they remain here during the whole year, and breed in
the marshes.  During the day they rest in flocks on the grassy plains
at some distance from the water.  Being at anchor, as I have said, in
one of the deep creeks between the islands of the Parana, as the
evening drew to a close, one of these scissor-beaks suddenly appeared.
The water was quite still, and many little fish were rising.  The bird
continued for a long time to skim the surface, flying in its wild and
irregular manner up and down the narrow canal, now dark with the
growing night and the shadows of the overhanging trees.  At Monte
Video, I observed that some large flocks during the day remained on the
mud-banks at the head of the harbour, in the same manner as on the
grassy plains near the Parana; and every evening they took flight
seaward.  From these facts I suspect that the Rhynchops generally
fishes by night, at which time many of the lower animals come most
abundantly to the surface.  M. Lesson states that he has seen these
birds opening the shells of the mactrae buried in the sand-banks on the
coast of Chile: from their weak bills, with the lower mandible so much
projecting, their short legs and long wings, it is very improbable that
this can be a general habit.

In our course down the Parana, I observed only three other birds, whose
habits are worth mentioning.  One is a small kingfisher (Ceryle
Americana); it has a longer tail than the European species, and hence
does not sit in so stiff and upright a position.  Its flight also,
instead of being direct and rapid, like the course of an arrow, is weak
and undulatory, as among the soft-billed birds.  It utters a low note,
like the clicking together of two small stones.  A small green parrot
(Conurus murinus), with a grey breast, appears to prefer the tall trees
on the islands to any other situation for its building-place.  A number
of nests are placed so close together as to form one great mass of
sticks. These parrots always live in flocks, and commit great ravages
on the corn-fields.  I was told, that near Colonia 2500 were killed in
the course of one year.  A bird with a forked tail, terminated by two
long feathers (Tyrannus savana), and named by the Spaniards
scissor-tail, is very common near Buenos Ayres: it commonly sits on a
branch of the _ombu_ tree, near a house, and thence takes a short
flight in pursuit of insects, and returns to the same spot.  When on
the wing it presents in its manner of flight and general appearance a
caricature-likeness of the common swallow.  It has the power of turning
very shortly in the air, and in so doing opens and shuts its tail,
sometimes in a horizontal or lateral and sometimes in a vertical
direction, just like a pair of scissors.

October 16th.--Some leagues below Rozario, the western shore of the
Parana is bounded by perpendicular cliffs, which extend in a long line
to below San Nicolas; hence it more resembles a sea-coast than that of
a fresh-water river. It is a great drawback to the scenery of the
Parana, that, from the soft nature of its banks, the water is very
muddy. The Uruguay, flowing through a granitic country, is much
clearer; and where the two channels unite at the head of the Plata, the
waters may for a long distance be distinguished by their black and red
colours.  In the evening, the wind being not quite fair, as usual we
immediately moored, and the next day, as it blew rather freshly, though
with a favouring current, the master was much too indolent to think of
starting.  At Bajada, he was described to me as "hombre muy aflicto"--a
man always miserable to get on; but certainly he bore all delays with
admirable resignation.  He was an old Spaniard, and had been many years
in this country.  He professed a great liking to the English, but
stoutly maintained that the battle of Trafalgar was merely won by the
Spanish captains having been all bought over; and that the only really
gallant action on either side was performed by the Spanish admiral.  It
struck me as rather characteristic, that this man should prefer his
countrymen being thought the worst of traitors, rather than unskilful
or cowardly.

18th and 19th.--We continued slowly to sail down the noble stream: the
current helped us but little.  We met, during our descent, very few
vessels.  One of the best gifts of nature, in so grand a channel of
communication, seems here wilfully thrown away--a river in which ships
might navigate from a temperate country, as surprisingly abundant in
certain productions as destitute of others, to another possessing a
tropical climate, and a soil which, according to the best of judges, M.
Bonpland, is perhaps unequalled in fertility in any part of the world.
How different would have been the aspect of this river if English
colonists had by good fortune first sailed up the Plata!  What noble
towns would now have occupied its shores!  Till the death of Francia,
the Dictator of Paraguay, these two countries must remain distinct, as
if placed on opposite sides of the globe. And when the old
bloody-minded tyrant is gone to his long account, Paraguay will be torn
by revolutions, violent in proportion to the previous unnatural calm.
That country will have to learn, like every other South American state,
that a republic cannot succeed till it contains a certain body of men
imbued with the principles of justice and honour.

October 20th.--Being arrived at the mouth of the Parana, and as I was
very anxious to reach Buenos Ayres, I went on shore at Las Conchas,
with the intention of riding there. Upon landing, I found to my great
surprise that I was to a certain degree a prisoner.  A violent
revolution having broken out, all the ports were laid under an embargo.
I could not return to my vessel, and as for going by land to the city,
it was out of the question.  After a long conversation with the
commandant, I obtained permission to go the next day to General Rolor,
who commanded a division of the rebels on this side the capital.  In
the morning I rode to the encampment.  The general, officers, and
soldiers, all appeared, and I believe really were, great villains.  The
general, the very evening before he left the city, voluntarily went to
the Governor, and with his hand to his heart, pledged his word of
honour that he at least would remain faithful to the last.  The general
told me that the city was in a state of close blockade, and that all he
could do was to give me a passport to the commander-in-chief of the
rebels at Quilmes. We had therefore to take a great sweep round the
city, and it was with much difficulty that we procured horses. My
reception at the encampment was quite civil, but I was told it was
impossible that I could be allowed to enter the city.  I was very
anxious about this, as I anticipated the Beagle's departure from the
Rio Plata earlier than it took place.  Having mentioned, however,
General Rosas's obliging kindness to me when at the Colorado, magic
itself could not have altered circumstances quicker than did this
conversation.  I was instantly told that though they could not give me
a passport, if I chose to leave my guide and horses, I might pass their
sentinels.  I was too glad to accept of this, and an officer was sent
with me to give directions that I should not be stopped at the bridge.
The road for the space of a league was quite deserted.  I met one party
of soldiers, who were satisfied by gravely looking at an old passport:
and at length I was not a little pleased to find myself within the city.

This revolution was supported by scarcely any pretext of grievances:
but in a state which, in the course of nine months (from February to
October, 1820), underwent fifteen changes in its government--each
governor, according to the constitution, being elected for three
years--it would be very unreasonable to ask for pretexts.  In this
case, a party of men--who, being attached to Rosas, were disgusted with
the governor Balcarce--to the number of seventy left the city, and with
the cry of Rosas the whole country took arms. The city was then
blockaded, no provisions, cattle or horses, were allowed to enter;
besides this, there was only a little skirmishing, and a few men daily
killed.  The outside party well knew that by stopping the supply of
meat they would certainly be victorious.  General Rosas could not have
known of this rising; but it appears to be quite consonant with the
plans of his party.  A year ago he was elected governor, but he refused
it, unless the Sala would also confer on him extraordinary powers. This
was refused, and since then his party have shown that no other governor
can keep his place.  The warfare on both sides was avowedly protracted
till it was possible to hear from Rosas.  A note arrived a few days
after I left Buenos Ayres, which stated that the General disapproved of
peace having been broken, but that he thought the outside party had
justice on their side.  On the bare reception of this, the Governor,
ministers, and part of the military, to the number of some hundreds,
fled from the city.  The rebels entered, elected a new governor, and
were paid for their services to the number of 5500 men. From these
proceedings, it was clear that Rosas ultimately would become the
dictator: to the term king, the people in this, as in other republics,
have a particular dislike.  Since leaving South America, we have heard
that Rosas has been elected, with powers and for a time altogether
opposed to the constitutional principles of the republic.

[1] The bizcacha (Lagostomus trichodactylus) somewhat resembles a large
rabbit, but with bigger gnawing teeth and a long tail; it has, however,
only three toes behind, like the agouti.  During the last three or four
years the skins of these animals have been sent to England for the sake
of the fur.

[2] Journal of Asiatic Soc., vol. v. p. 363.

[3] I need hardly state here that there is good evidence against any
horse living in America at the time of Columbus.

[4] Cuvier. Ossemens Fossils, tom. i. p. 158.

[5] This is the geographical division followed by Lichtenstein,
Swainson, Erichson, and Richardson.  The section from Vera Cruz to
Acapulco, given by Humboldt in the Polit. Essay on Kingdom of N. Spain
will show how immense a barrier the Mexican table-land forms.  Dr.
Richardson, in his admirable Report on the Zoology of N. America read
before the Brit. Assoc. 1836 (p. 157), talking of the identification of
a Mexican animal with the Synetheres prehensilis, says, "We do not know
with what propriety, but if correct, it is, if not a solitary instance,
at least very nearly so, of a rodent animal being common to North and
South America."

[6] See Dr. Richardson's Report, p. 157; also L'Institut, 1837, p. 253.
Cuvier says the kinkajou is found in the larger Antilles, but this is
doubtful.  M. Gervais states that the Didelphis crancrivora is found
there.  It is certain that the West Indies possess some mammifers
peculiar to themselves.  A tooth of a mastadon has been brought from
Bahama; Edin. New Phil. Journ., 1826, p. 395.

[7] See the admirable Appendix by Dr. Buckland to Beechey's Voyage;
also the writings of Chamisso in Kotzebue's Voyage.

[8] In Captain Owen's Surveying Voyage (vol. ii. p. 274) there is a
curious account of the effects of a drought on the elephants, at
Benguela (west coast of Africa).  "A number of these animals had some
time since entered the town, in a body, to possess themselves of the
wells, not being able to procure any water in the country.  The
inhabitants mustered, when a desperate conflict ensued, which
terminated in the ultimate discomfiture of the invaders, but not until
they had killed one man, and wounded several others." The town is said
to have a population of nearly three thousand!  Dr. Malcolmson informs
me that, during a great drought in India, the wild animals entered the
tents of some troops at Ellore, and that a hare drank out of a vessel
held by the adjutant of the regiment.

[9] Travels, vol. i. p. 374.

[10] These droughts to a certain degree seem to be almost periodical; I
was told the dates of several others, and the intervals were about
fifteen years.



CHAPTER VIII

BANDA ORIENTAL AND PATAGONIA

Excursion to Colonia del Sacramiento--Value of an Estancia--Cattle, how
counted--Singular Breed of Oxen--Perforated Pebbles--Shepherd
Dogs--Horses broken-in, Gauchos riding--Character of Inhabitants--Rio
Plata--Flocks of Butterflies--Aeronaut Spiders--Phosphorescence of the
Sea--Port Desire--Guanaco--Port St. Julian--Geology of
Patagonia--Fossil gigantic Animal--Types of Organization
constant--Change in the Zoology of America--Causes of Extinction.


HAVING been delayed for nearly a fortnight in the city, I was glad to
escape on board a packet bound for Monte Video.  A town in a state of
blockade must always be a disagreeable place of residence; in this case
moreover there were constant apprehensions from robbers within.  The
sentinels were the worst of all; for, from their office and from having
arms in their hands, they robbed with a degree of authority which other
men could not imitate.

Our passage was a very long and tedious one.  The Plata looks like a
noble estuary on the map; but is in truth a poor affair.  A wide
expanse of muddy water has neither grandeur nor beauty.  At one time of
the day, the two shores, both of which are extremely low, could just be
distinguished from the deck.  On arriving at Monte Video I found that
the Beagle would not sail for some time, so I prepared for a short
excursion in this part of Banda Oriental.  Everything which I have said
about the country near Maldonado is applicable to Monte Video; but the
land, with the one exception of the Green Mount 450 feet high, from
which it takes its name, is far more level.  Very little of the
undulating grassy plain is enclosed; but near the town there are a few
hedge-banks, covered with agaves, cacti, and fennel.

November 14th.--We left Monte Video in the afternoon. I intended to
proceed to Colonia del Sacramiento, situated on the northern bank of
the Plata and opposite to Buenos Ayres, and thence, following up the
Uruguay, to the village of Mercedes on the Rio Negro (one of the many
rivers of this name in South America), and from this point to return
direct to Monte Video.  We slept at the house of my guide at Canelones.
In the morning we rose early, in the hopes of being able to ride a good
distance; but it was a vain attempt, for all the rivers were flooded.
We passed in boats the streams of Canelones, St. Lucia, and San Jose,
and thus lost much time.  On a former excursion I crossed the Lucia
near its mouth, and I was surprised to observe how easily our horses,
although not used to swim, passed over a width of at least six hundred
yards.  On mentioning this at Monte Video, I was told that a vessel
containing some mountebanks and their horses, being wrecked in the
Plata, one horse swam seven miles to the shore.  In the course of the
day I was amused by the dexterity with which a Gaucho forced a restive
horse to swim a river.  He stripped off his clothes, and jumping on its
back, rode into the water till it was out of its depth; then slipping
off over the crupper, he caught hold of the tail, and as often as the
horse turned round the man frightened it back by splashing water in its
face. As soon as the horse touched the bottom on the other side, the
man pulled himself on, and was firmly seated, bridle in hand, before
the horse gained the bank.  A naked man on a naked horse is a fine
spectacle; I had no idea how well the two animals suited each other.
The tail of a horse is a very useful appendage; I have passed a river
in a boat with four people in it, which was ferried across in the same
way as the Gaucho.  If a man and horse have to cross a broad river, the
best plan is for the man to catch hold of the pommel or mane, and help
himself with the other arm.

We slept and stayed the following day at the post of Cufre.  In the
evening the postman or letter-carrier arrived. He was a day after his
time, owing to the Rio Rozario being flooded.  It would not, however,
be of much consequence; for, although he had passed through some of the
principal towns in Banda Oriental, his luggage consisted of two
letters! The view from the house was pleasing; an undulating green
surface, with distant glimpses of the Plata.  I find that I look at
this province with very different eyes from what I did upon my first
arrival.  I recollect I then thought it singularly level; but now,
after galloping over the Pampas, my only surprise is, what could have
induced me ever to call it level.  The country is a series of
undulations, in themselves perhaps not absolutely great, but, as
compared to the plains of St. Fe, real mountains.  From these
inequalities there is an abundance of small rivulets, and the turf is
green and luxuriant.

November 17th.--We crossed the Rozario, which was deep and rapid, and
passing the village of Colla, arrived at midday at Colonia del
Sacramiento.  The distance is twenty leagues, through a country covered
with fine grass, but poorly stocked with cattle or inhabitants.  I was
invited to sleep at Colonia, and to accompany on the following day a
gentleman to his estancia, where there were some limestone rocks.  The
town is built on a stony promontory something in the same manner as at
Monte Video.  It is strongly fortified, but both fortifications and
town suffered much in the Brazilian war.  It is very ancient; and the
irregularity of the streets, and the surrounding groves of old orange
and peach trees, gave it a pretty appearance. The church is a curious
ruin; it was used as a powder-magazine, and was struck by lightning in
one of the ten thousand thunderstorms of the Rio Plata.  Two-thirds of
the building were blown away to the very foundation; and the rest
stands a shattered and curious monument of the united powers of
lightning and gunpowder.  In the evening I wandered about the
half-demolished walls of the town.  It was the chief seat of the
Brazilian war;--a war most injurious to this country, not so much in
its immediate effects, as in being the origin of a multitude of
generals and all other grades of officers.  More generals are numbered
(but not paid) in the United Provinces of La Plata than in the United
Kingdom of Great Britain.  These gentlemen have learned to like power,
and do not object to a little skirmishing.  Hence there are many always
on the watch to create disturbance and to overturn a government which
as yet has never rested on any staple foundation.  I noticed, however,
both here and in other places, a very general interest in the ensuing
election for the President; and this appears a good sign for the
prosperity of this little country.  The inhabitants do not require much
education in their representatives; I heard some men discussing the
merits of those for Colonia; and it was said that, "although they were
not men of business, they could all sign their names:" with this they
seemed to think every reasonable man ought to be satisfied.

18th.--Rode with my host to his estancia, at the Arroyo de San Juan. In
the evening we took a ride round the estate: it contained two square
leagues and a half, and was situated in what is called a rincon; that
is, one side was fronted by the Plata, and the two others guarded by
impassable brooks.  There was an excellent port for little vessels, and
an abundance of small wood, which is valuable as supplying fuel to
Buenos Ayres.  I was curious to know the value of so complete an
estancia.  Of cattle there were 3000, and it would well support three
or four times that number; of mares 800, together with 150 broken-in
horses, and 600 sheep.  There was plenty of water and limestone, a
rough house, excellent corrals, and a peach orchard.  For all this he
had been offered 2000 Pounds, and he only wanted 500 Pounds additional,
and probably would sell it for less.  The chief trouble with an
estancia is driving the cattle twice a week to a central spot, in order
to make them tame, and to count them.  This latter operation would be
thought difficult, where there are ten or fifteen thousand head
together.  It is managed on the principle that the cattle invariably
divide themselves into little troops of from forty to one hundred. Each
troop is recognized by a few peculiarly marked animals, and its number
is known: so that, one being lost out of ten thousand, it is perceived
by its absence from one of the tropillas.  During a stormy night the
cattle all mingle together; but the next morning the tropillas separate
as before; so that each animal must know its fellow out of ten thousand
others.

On two occasions I met with in this province some oxen of a very
curious breed, called nata or niata.  They appear externally to hold
nearly the same relation to other cattle, which bull or pug dogs do to
other dogs.  Their forehead is very short and broad, with the nasal end
turned up, and the upper lip much drawn back; their lower jaws project
beyond the upper, and have a corresponding upward curve; hence their
teeth are always exposed.  Their nostrils are seated high up and are
very open; their eyes project outwards. When walking they carry their
heads low, on a short neck; and their hinder legs are rather longer
compared with the front legs than is usual.  Their bare teeth, their
short heads, and upturned nostrils give them the most ludicrous
self-confident air of defiance imaginable.

Since my return, I have procured a skeleton head, through the kindness
of my friend Captain Sulivan, R. N., which is now deposited in the
College of Surgeons. [1] Don F. Muniz, of Luxan, has kindly collected
for me all the information which he could respecting this breed.  From
his account it seems that about eighty or ninety years ago, they were
rare and kept as curiosities at Buenos Ayres.  The breed is universally
believed to have originated amongst the Indians southward of the Plata;
and that it was with them the commonest kind.  Even to this day, those
reared in the provinces near the Plata show their less civilized
origin, in being fiercer than common cattle, and in the cow easily
deserting her first calf, if visited too often or molested.  It is a
singular fact that an almost similar structure to the abnormal [2] one
of the niata breed, characterizes, as I am informed by Dr. Falconer,
that great extinct ruminant of India, the Sivatherium.  The breed is
very _true_; and a niata bull and cow invariably produce niata calves.
A niata bull with a common cow, or the reverse cross, produces
offspring having an intermediate character, but with the niata
characters strongly displayed: according to Senor Muniz, there is the
clearest evidence, contrary to the common belief of agriculturists in
analogous cases, that the niata cow when crossed with a common bull
transmits her peculiarities more strongly than the niata bull when
crossed with a common cow.  When the pasture is tolerably long, the
niata cattle feed with the tongue and palate as well as common cattle;
but during the great droughts, when so many animals perish, the niata
breed is under a great disadvantage, and would be exterminated if not
attended to; for the common cattle, like horses, are able just to keep
alive, by browsing with their lips on twigs of trees and reeds; this
the niatas cannot so well do, as their lips do not join, and hence they
are found to perish before the common cattle.  This strikes me as a
good illustration of how little we are able to judge from the ordinary
habits of life, on what circumstances, occurring only at long
intervals, the rarity or extinction of a species may be determined.

November 19th.--Passing the valley of Las Vacas, we slept at a house of
a North American, who worked a lime-kiln on the Arroyo de las Vivoras.
In the morning we rode to a protecting headland on the banks of the
river, called Punta Gorda.  On the way we tried to find a jaguar. There
were plenty of fresh tracks, and we visited the trees, on which they
are said to sharpen their claws; but we did not succeed in disturbing
one.  From this point the Rio Uruguay presented to our view a noble
volume of water.  From the clearness and rapidity of the stream, its
appearance was far superior to that of its neighbour the Parana.  On
the opposite coast, several branches from the latter river entered the
Uruguay.  As the sun was shining, the two colours of the waters could
be seen quite distinct.

In the evening we proceeded on our road towards Mercedes on the Rio
Negro.  At night we asked permission to sleep at an estancia at which
we happened to arrive.  It was a very large estate, being ten leagues
square, and the owner is one of the greatest landowners in the country.
His nephew had charge of it, and with him there was a captain in the
army, who the other day ran away from Buenos Ayres. Considering their
station, their conversation was rather amusing.  They expressed, as was
usual, unbounded astonishment at the globe being round, and could
scarcely credit that a hole would, if deep enough, come out on the
other side.  They had, however, heard of a country where there were six
months of light and six of darkness, and where the inhabitants were
very tall and thin!  They were curious about the price and condition of
horses and cattle in England. Upon finding out we did not catch our
animals with the lazo, they cried out, "Ah, then, you use nothing but
the bolas:" the idea of an enclosed country was quite new to them.  The
captain at last said, he had one question to ask me, which he should be
very much obliged if I would answer with all truth.  I trembled to
think how deeply scientific it would be: it was, "Whether the ladies of
Buenos Ayres were not the handsomest in the world." I replied, like a
renegade, "Charmingly so." He added, "I have one other question: Do
ladies in any other part of the world wear such large combs?" I
solemnly assured him that they did not.  They were absolutely
delighted.  The captain exclaimed, "Look there! a man who has seen half
the world says it is the case; we always thought so, but now we know
it." My excellent judgment in combs and beauty procured me a most
hospitable reception; the captain forced me to take his bed, and he
would sleep on his recado.

21st.--Started at sunrise, and rode slowly during the whole day.  The
geological nature of this part of the province was different from the
rest, and closely resembled that of the Pampas.  In consequence, there
were immense beds of the thistle, as well as of the cardoon: the whole
country, indeed, may be called one great bed of these plants.  The two
sorts grow separate, each plant in company with its own kind.  The
cardoon is as high as a horse's back, but the Pampas thistle is often
higher than the crown of the rider's head.  To leave the road for a
yard is out of the question; and the road itself is partly, and in some
cases entirely closed.  Pasture, of course there is none; if cattle or
horses once enter the bed, they are for the time completely lost. Hence
it is very hazardous to attempt to drive cattle at this season of the
year; for when jaded enough to face the thistles, they rush among them,
and are seen no more.  In these districts there are very few estancias,
and these few are situated in the neighbourhood of damp valleys, where
fortunately neither of these overwhelming plants can exist. As night
came on before we arrived at our journey's end, we slept at a miserable
little hovel inhabited by the poorest people.  The extreme though
rather formal courtesy of our host and hostess, considering their grade
of life, was quite delightful.

November 22nd.--Arrived at an estancia on the Berquelo belonging to a
very hospitable Englishman, to whom I had a letter of introduction from
my friend Mr. Lumb.  I stayed here three days.  One morning I rode with
my host to the Sierra del Pedro Flaco, about twenty miles up the Rio
Negro.  Nearly the whole country was covered with good though coarse
grass, which was as high as a horse's belly; yet there were square
leagues without a single head of cattle. The province of Banda
Oriental, if well stocked, would support an astonishing number of
animals, at present the annual export of hides from Monte Video amounts
to three hundred thousand; and the home consumption, from waste, is
very considerable.  An "estanciero" told me that he often had to send
large herds of cattle a long journey to a salting establishment, and
that the tired beasts were frequently obliged to be killed and skinned;
but that he could never persuade the Gauchos to eat of them, and every
evening a fresh beast was slaughtered for their suppers!  The view of
the Rio Negro from the Sierra was more picturesque than any other which
I saw in this province.  The river, broad, deep, and rapid, wound at
the foot of a rocky precipitous cliff: a belt of wood followed its
course, and the horizon terminated in the distant undulations of the
turf-plain.

When in this neighbourhood, I several times heard of the Sierra de las
Cuentas: a hill distant many miles to the northward.  The name
signifies hill of beads.  I was assured that vast numbers of little
round stones, of various colours, each with a small cylindrical hole,
are found there.  Formerly the Indians used to collect them, for the
purpose of making necklaces and bracelets--a taste, I may observe,
which is common to all savage nations, as well as to the most polished.
I did not know what to understand from this story, but upon mentioning
it at the Cape of Good Hope to Dr. Andrew Smith, he told me that he
recollected finding on the south-eastern coast of Africa, about one
hundred miles to the eastward of St.  John's river, some quartz
crystals with their edges blunted from attrition, and mixed with gravel
on the sea-beach.  Each crystal was about five lines in diameter, and
from an inch to an inch and a half in length.  Many of them had a small
canal extending from one extremity to the other, perfectly cylindrical,
and of a size that readily admitted a coarse thread or a piece of fine
catgut.  Their colour was red or dull white.  The natives were
acquainted with this structure in crystals.  I have mentioned these
circumstances because, although no crystallized body is at present
known to assume this form, it may lead some future traveller to
investigate the real nature of such stones.


While staying at this estancia, I was amused with what I saw and heard
of the shepherd-dogs of the country. [3] When riding, it is a common
thing to meet a large flock of sheep guarded by one or two dogs, at the
distance of some miles from any house or man.  I often wondered how so
firm a friendship had been established.  The method of education
consists in separating the puppy, while very young, from the bitch, and
in accustoming it to its future companions. An ewe is held three or
four times a day for the little thing to suck, and a nest of wool is
made for it in the sheep-pen; at no time is it allowed to associate
with other dogs, or with the children of the family.  The puppy is,
moreover, generally castrated; so that, when grown up, it can scarcely
have any feelings in common with the rest of its kind.  From this
education it has no wish to leave the flock, and just as another dog
will defend its master, man, so will these the sheep.  It is amusing to
observe, when approaching a flock, how the dog immediately advances
barking, and the sheep all close in his rear, as if round the oldest
ram.  These dogs are also easily taught to bring home the flock, at a
certain hour in the evening.  Their most troublesome fault, when young,
is their desire of playing with the sheep; for in their sport they
sometimes gallop their poor subjects most unmercifully.

The shepherd-dog comes to the house every day for some meat, and as
soon as it is given him, he skulks away as if ashamed of himself.  On
these occasions the house-dogs are very tyrannical, and the least of
them will attack and pursue the stranger.  The minute, however, the
latter has reached the flock, he turns round and begins to bark, and
then all the house-dogs take very quickly to their heels.  In a similar
manner a whole pack of the hungry wild dogs will scarcely ever (and I
was told by some never) venture to attack a flock guarded by even one
of these faithful shepherds.  The whole account appears to me a curious
instance of the pliability of the affections in the dog; and yet,
whether wild or however educated, he has a feeling of respect or fear
for those that are fulfilling their instinct of association.  For we
can understand on no principle the wild dogs being driven away by the
single one with its flock, except that they consider, from some
confused notion, that the one thus associated gains power, as if in
company with its own kind. F. Cuvier has observed that all animals that
readily enter into domestication, consider man as a member of their own
society, and thus fulfil their instinct of association.  In the above
case the shepherd-dog ranks the sheep as its fellow-brethren, and thus
gains confidence; and the wild dogs, though knowing that the individual
sheep are not dogs, but are good to eat, yet partly consent to this
view when seeing them in a flock with a shepherd-dog at their head.

One evening a "domidor" (a subduer of horses) came for the purpose of
breaking-in some colts.  I will describe the preparatory steps, for I
believe they have not been mentioned by other travellers.  A troop of
wild young horses is driven into the corral, or large enclosure of
stakes, and the door is shut.  We will suppose that one man alone has
to catch and mount a horse, which as yet had never felt bridle or
saddle.  I conceive, except by a Gaucho, such a feat would be utterly
impracticable.  The Gaucho picks out a full-grown colt; and as the
beast rushes round the circus he throws his lazo so as to catch both
the front legs.  Instantly the horse rolls over with a heavy shock, and
whilst struggling on the ground, the Gaucho, holding the lazo tight,
makes a circle, so as to catch one of the hind legs just beneath the
fetlock, and draws it close to the two front legs: he then hitches the
lazo, so that the three are bound together.  Then sitting on the
horse's neck, he fixes a strong bridle, without a bit, to the lower
jaw: this he does by passing a narrow thong through the eye-holes at
the end of the reins, and several times round both jaw and tongue.  The
two front legs are now tied closely together with a strong leathern
thong, fastened by a slip-knot.  The lazo, which bound the three
together, being then loosed, the horse rises with difficulty.  The
Gaucho now holding fast the bridle fixed to the lower jaw, leads the
horse outside the corral.  If a second man is present (otherwise the
trouble is much greater) he holds the animal's head, whilst the first
puts on the horsecloths and saddle, and girths the whole together.
During this operation, the horse, from dread and astonishment at thus
being bound round the waist, throws himself over and over again on the
ground, and, till beaten, is unwilling to rise.  At last, when the
saddling is finished, the poor animal can hardly breathe from fear, and
is white with foam and sweat.  The man now prepares to mount by
pressing heavily on the stirrup, so that the horse may not lose its
balance; and at the moment that he throws his leg over the animal's
back, he pulls the slip-knot binding the front legs, and the beast is
free.  Some "domidors" pull the knot while the animal is lying on the
ground, and, standing over the saddle, allow him to rise beneath them.
The horse, wild with dread, gives a few most violent bounds, and then
starts off at full gallop: when quite exhausted, the man, by patience,
brings him back to the corral, where, reeking hot and scarcely alive,
the poor beast is let free.  Those animals which will not gallop away,
but obstinately throw themselves on the ground, are by far the most
troublesome.  This process is tremendously severe, but in two or three
trials the horse is tamed.  It is not, however, for some weeks that the
animal is ridden with the iron bit and solid ring, for it must learn to
associate the will of its rider with the feel of the rein, before the
most powerful bridle can be of any service.

Animals are so abundant in these countries, that humanity and
self-interest are not closely united; therefore I fear it is that the
former is here scarcely known.  One day, riding in the Pampas with a
very respectable "estanciero," my horse, being tired, lagged behind.
The man often shouted to me to spur him.  When I remonstrated that it
was a pity, for the horse was quite exhausted, he cried out, "Why
not?--never mind--spur him--it is my horse." I had then some difficulty
in making him comprehend that it was for the horse's sake, and not on
his account, that I did not choose to use my spurs.  He exclaimed, with
a look of great surprise, "Ah, Don Carlos, que cosa!" It was clear that
such an idea had never before entered his head.

The Gauchos are well known to be perfect riders. The idea of being
thrown, let the horse do what it likes; never enters their head.  Their
criterion of a good rider is, a man who can manage an untamed colt, or
who, if his horse falls, alights on his own feet, or can perform other
such exploits. I have heard of a man betting that he would throw his
horse down twenty times, and that nineteen times he would not fall
himself.  I recollect seeing a Gaucho riding a very stubborn horse,
which three times successively reared so high as to fall backwards with
great violence.  The man judged with uncommon coolness the proper
moment for slipping off, not an instant before or after the right time;
and as soon as the horse got up, the man jumped on his back, and at
last they started at a gallop.  The Gaucho never appears to exert any
muscular force.  I was one day watching a good rider, as we were
galloping along at a rapid pace, and thought to myself, "Surely if the
horse starts, you appear so careless on your seat, you must fall." At
this moment, a male ostrich sprang from its nest right beneath the
horse's nose: the young colt bounded on one side like a stag; but as
for the man, all that could be said was, that he started and took
fright with his horse.

In Chile and Peru more pains are taken with the mouth of the horse than
in La Plata, and this is evidently a consequence of the more intricate
nature of the country.  In Chile a horse is not considered perfectly
broken, till he can be brought up standing, in the midst of his full
speed, on any particular spot,--for instance, on a cloak thrown on the
ground: or, again, he will charge a wall, and rearing, scrape the
surface with his hoofs.  I have seen an animal bounding with spirit,
yet merely reined by a fore-finger and thumb, taken at full gallop
across a courtyard, and then made to wheel round the post of a veranda
with great speed, but at so equal a distance, that the rider, with
outstretched arm, all the while kept one finger rubbing the post.  Then
making a demi-volte in the air, with the other arm outstretched in a
like manner, he wheeled round, with astonishing force, in an opposite
direction.

Such a horse is well broken; and although this at first may appear
useless, it is far otherwise.  It is only carrying that which is daily
necessary into perfection.  When a bullock is checked and caught by the
lazo, it will sometimes gallop round and round in a circle, and the
horse being alarmed at the great strain, if not well broken, will not
readily turn like the pivot of a wheel.  In consequence many men have
been killed; for if the lazo once takes a twist round a man's body, it
will instantly, from the power of the two opposed animals, almost cut
him in twain.  On the same principle the races are managed; the course
is only two or three hundred yards long, the wish being to have horses
that can make a rapid dash.  The race-horses are trained not only to
stand with their hoofs touching a line, but to draw all four feet
together, so as at the first spring to bring into play the full action
of the hind-quarters.  In Chile I was told an anecdote, which I believe
was true; and it offers a good illustration of the use of a well-broken
animal.  A respectable man riding one day met two others, one of whom
was mounted on a horse, which he knew to have been stolen from himself.
He challenged them; they answered him by drawing their sabres and
giving chase.  The man, on his good and fleet beast, kept just ahead:
as he passed a thick bush he wheeled round it, and brought up his horse
to a dead check.  The pursuers were obliged to shoot on one side and
ahead.  Then instantly dashing on, right behind them, he buried his
knife in the back of one, wounded the other, recovered his horse from
the dying robber, and rode home.  For these feats of horsemanship two
things are necessary: a most severe bit, like the Mameluke, the power
of which, though seldom used, the horse knows full well; and large
blunt spurs, that can be applied either as a mere touch, or as an
instrument of extreme pain. I conceive that with English spurs, the
slightest touch of which pricks the skin, it would be impossible to
break in a horse after the South American fashion.

At an estancia near Las Vacas large numbers of mares are weekly
slaughtered for the sake of their hides, although worth only five paper
dollars, or about half a crown apiece. It seems at first strange that
it can answer to kill mares for such a trifle; but as it is thought
ridiculous in this country ever to break in or ride a mare, they are of
no value except for breeding.  The only thing for which I ever saw
mares used, was to tread out wheat from the ear, for which purpose they
were driven round a circular enclosure, where the wheat-sheaves were
strewed.  The man employed for slaughtering the mares happened to be
celebrated for his dexterity with the lazo.  Standing at the distance
of twelve yards from the mouth of the corral, he has laid a wager that
he would catch by the legs every animal, without missing one, as it
rushed past him.  There was another man who said he would enter the
corral on foot, catch a mare, fasten her front legs together, drive her
out, throw her down, kill, skin, and stake the hide for drying (which
latter is a tedious job); and he engaged that he would perform this
whole operation on twenty-two animals in one day.  Or he would kill and
take the skin off fifty in the same time.  This would have been a
prodigious task, for it is considered a good day's work to skin and
stake the hides of fifteen or sixteen animals.

November 26th.--I set out on my return in a direct line for Monte
Video.  Having heard of some giant's bones at a neighbouring farm-house
on the Sarandis, a small stream entering the Rio Negro, I rode there
accompanied by my host, and purchased for the value of eighteen pence
the head of the Toxodon. [4] When found it was quite perfect; but the
boys knocked out some of the teeth with stones, and then set up the
head as a mark to throw at.  By a most fortunate chance I found a
perfect tooth, which exactly fitted one of the sockets in this skull,
embedded by itself on the banks of the Rio Tercero, at the distance of
about 180 miles from this place.  I found remains of this extraordinary
animal at two other places, so that it must formerly have been common.
I found here, also, some large portions of the armour of a gigantic
armadillo-like animal, and part of the great head of a Mylodon.  The
bones of this head are so fresh, that they contain, according to the
analysis by Mr. T. Reeks, seven per cent of animal matter; and when
placed in a spirit-lamp, they burn with a small flame.  The number of
the remains embedded in the grand estuary deposit which forms the
Pampas and covers the granitic rocks of Banda Oriental, must be
extraordinarily great.  I believe a straight line drawn in any
direction through the Pampas would cut through some skeleton or bones.
Besides those which I found during my short excursions, I heard of many
others, and the origin of such names as "the stream of the animal,"
"the hill of the giant," is obvious.  At other times I heard of the
marvellous property of certain rivers, which had the power of changing
small bones into large; or, as some maintained, the bones themselves
grew.  As far as I am aware, not one of these animals perished, as was
formerly supposed, in the marshes or muddy river-beds of the present
land, but their bones have been exposed by the streams intersecting the
subaqueous deposit in which they were originally embedded. We may
conclude that the whole area of the Pampas is one wide sepulchre of
these extinct gigantic quadrupeds.

By the middle of the day, on the 28th, we arrived at Monte Video,
having been two days and a half on the road. The country for the whole
way was of a very uniform character, some parts being rather more rocky
and hilly than near the Plata.  Not far from Monte Video we passed
through the village of Las Pietras, so named from some large rounded
masses of syenite.  Its appearance was rather pretty.  In this country
a few fig-trees round a group of houses, and a site elevated a hundred
feet above the general level, ought always to be called picturesque.


During the last six months I have had an opportunity of seeing a little
of the character of the inhabitants of these provinces.  The Gauchos,
or countryrmen, are very superior to those who reside in the towns. The
Gaucho is invariably most obliging, polite, and hospitable: I did not
meet with even one instance of rudeness or inhospitality.  He is
modest, both respecting himself and country, but at the same time a
spirited, bold fellow.  On the other hand, many robberies are
committed, and there is much bloodshed: the habit of constantly wearing
the knife is the chief cause of the latter.  It is lamentable to hear
how many lives are lost in trifling quarrels.  In fighting, each party
tries to mark the face of his adversary by slashing his nose or eyes;
as is often attested by deep and horrid-looking scars.  Robberies are a
natural consequence of universal gambling, much drinking, and extreme
indolence.  At Mercedes I asked two men why they did not work.  One
gravely said the days were too long; the other that he was too poor.
The number of horses and the profusion of food are the destruction of
all industry.  Moreover, there are so many feast-days; and again,
nothing can succeed without it be begun when the moon is on the
increase; so that half the month is lost from these two causes.

Police and justice are quite inefficient.  If a man who is poor commits
murder and is taken, he will be imprisoned, and perhaps even shot; but
if he is rich and has friends, he may rely on it no very severe
consequence will ensue. It is curious that the most respectable
inhabitants of the country invariably assist a murderer to escape: they
seem to think that the individual sins against the government, and not
against the people.  A traveller has no protection besides his
fire-arms; and the constant habit of carrying them is the main check to
more frequent robberies. The character of the higher and more educated
classes who reside in the towns, partakes, but perhaps in a lesser
degree, of the good parts of the Gaucho, but is, I fear, stained by
many vices of which he is free.  Sensuality, mockery of all religion,
and the grossest corruption, are far from uncommon.  Nearly every
public officer can be bribed.  The head man in the post-office sold
forged government franks. The governor and prime minister openly
combined to plunder the state.  Justice, where gold came into play, was
hardly expected by any one.  I knew an Englishman, who went to the
Chief Justice (he told me, that not then understanding the ways of the
place, he trembled as he entered the room), and said, "Sir, I have come
to offer you two hundred (paper) dollars (value about five pounds
sterling) if you will arrest before a certain time a man who has
cheated me.  I know it is against the law, but my lawyer (naming him)
recommended me to take this step." The Chief Justice smiled
acquiescence, thanked him, and the man before night was safe in prison.
With this entire want of principle in many of the leading men, with the
country full of ill-paid turbulent officers, the people yet hope that a
democratic form of government can succeed!

On first entering society in these countries, two or three features
strike one as particularly remarkable.  The polite and dignified
manners pervading every rank of life, the excellent taste displayed by
the women in their dresses, and the equality amongst all ranks.  At the
Rio Colorado some men who kept the humblest shops used to dine with
General Rosas.  A son of a major at Bahia Blanca gained his livelihood
by making paper cigars, and he wished to accompany me, as guide or
servant, to Buenos Ayres, but his father objected on the score of the
danger alone.  Many officers in the army can neither read nor write,
yet all meet in society as equals.  In Entre Rios, the Sala consisted
of only six representatives.  One of them kept a common shop, and
evidently was not degraded by the office.  All this is what would be
expected in a new country; nevertheless the absence of gentlemen by
profession appears to an Englishman something strange.

When speaking of these countries, the manner in which they have been
brought up by their unnatural parent, Spain, should always be borne in
mind.  On the whole, perhaps, more credit is due for what has been
done, than blame for that which may be deficient.  It is impossible to
doubt but that the extreme liberalism of these countries must
ultimately lead to good results.  The very general toleration of
foreign religions, the regard paid to the means of education, the
freedom of the press, the facilities offered to all foreigners, and
especially, as I am bound to add, to every one professing the humblest
pretensions to science, should be recollected with gratitude by those
who have visited Spanish South America.

December 6th.--The Beagle sailed from the Rio Plata, never again to
enter its muddy stream.  Our course was directed to Port Desire, on the
coast of Patagonia.  Before proceeding any further, I will here put
together a few observations made at sea.

Several times when the ship has been some miles off the mouth of the
Plata, and at other times when off the shores of Northern Patagonia, we
have been surrounded by insects. One evening, when we were about ten
miles from the Bay of San Blas, vast numbers of butterflies, in bands
or flocks of countless myriads, extended as far as the eye could range.
Even by the aid of a telescope it was not possible to see a space free
from butterflies.  The seamen cried out "it was snowing butterflies,"
and such in fact was the appearance. More species than one were
present, but the main part belonged to a kind very similar to, but not
identical with, the common English Colias edusa.  Some moths and
hymenoptera accompanied the butterflies; and a fine beetle (Calosoma)
flew on board.  Other instances are known of this beetle having been
caught far out at sea; and this is the more remarkable, as the greater
number of the Carabidae seldom or never take wing.  The day had been
fine and calm, and the one previous to it equally so, with light and
variable airs.  Hence we cannot suppose that the insects were blown off
the land, but we must conclude that they voluntarily took flight.  The
great bands of the Colias seem at first to afford an instance like
those on record of the migrations of another butterfly, Vanessa cardui;
[5] but the presence of other insects makes the case distinct, and even
less intelligible.  Before sunset a strong breeze sprung up from the
north, and this must have caused tens of thousands of the butterflies
and other insects to have perished.

On another occasion, when seventeen miles off Cape Corrientes, I had a
net overboard to catch pelagic animals. Upon drawing it up, to my
surprise, I found a considerable number of beetles in it, and although
in the open sea, they did not appear much injured by the salt water.  I
lost some of the specimens, but those which I preserved belonged to the
genera Colymbetes, Hydroporus, Hydrobius (two species), Notaphus,
Cynucus, Adimonia, and Scarabaeus.  At first I thought that these
insects had been blown from the shore; but upon reflecting that out of
the eight species four were aquatic, and two others partly so in their
habits, it appeared to me most probable that they were floated into the
sea by a small stream which drains a lake near Cape Corrientes. On any
supposition it is an interesting circumstance to find live insects
swimming in the open ocean seventeen miles from the nearest point of
land.  There are several accounts of insects having been blown off the
Patagonian shore.  Captain Cook observed it, as did more lately Captain
King of the Adventure.  The cause probably is due to the want of
shelter, both of trees and hills, so that an insect on the wing with an
off-shore breeze, would be very apt to be blown out to sea.  The most
remarkable instance I have known of an insect being caught far from the
land, was that of a large grasshopper (Acrydium), which flew on board,
when the Beagle was to windward of the Cape de Verd Islands, and when
the nearest point of land, not directly opposed to the trade-wind, was
Cape Blanco on the coast of Africa, 370 miles distant. [6]

On several occasions, when the Beagle has been within the mouth of the
Plata, the rigging has been coated with the web of the Gossamer Spider.
One day (November 1st, 1832) I paid particular attention to this
subject.  The weather had been fine and clear, and in the morning the
air was full of patches of the flocculent web, as on an autumnal day in
England.  The ship was sixty miles distant from the land, in the
direction of a steady though light breeze.  Vast numbers of a small
spider, about one-tenth of an inch in length, and of a dusky red
colour, were attached to the webs.  There must have been, I should
suppose, some thousands on the ship.  The little spider, when first
coming in contact with the rigging, was always seated on a single
thread, and not on the flocculent mass.  This latter seems merely to be
produced by the entanglement of the single threads.  The spiders were
all of one species, but of both sexes, together with young ones. These
latter were distinguished by their smaller size and more dusky colour.
I will not give the description of this spider, but merely state that
it does not appear to me to be included in any of Latreille's genera.
The little aeronaut as soon as it arrived on board was very active,
running about, sometimes letting itself fall, and then reascending the
same thread; sometimes employing itself in making a small and very
irregular mesh in the corners between the ropes.  It could run with
facility on the surface of the water.  When disturbed it lifted up its
front legs, in the attitude of attention.  On its first arrival it
appeared very thirsty, and with exserted maxillae drank eagerly of
drops of water, this same circumstance has been observed by Strack: may
it not be in consequence of the little insect having passed through a
dry and rarefied atmosphere?  Its stock of web seemed inexhaustible.
While watching some that were suspended by a single thread, I several
times observed that the slightest breath of air bore them away out of
sight, in a horizontal line.

On another occasion (25th) under similar circumstances, I repeatedly
observed the same kind of small spider, either when placed or having
crawled on some little eminence, elevate its abdomen, send forth a
thread, and then sail away horizontally, but with a rapidity which was
quite unaccountable.  I thought I could perceive that the spider,
before performing the above preparatory steps, connected its legs
together with the most delicate threads, but I am not sure whether this
observation was correct.

One day, at St. Fe, I had a better opportunity of observing some
similar facts.  A spider which was about three-tenths of an inch in
length, and which in its general appearance resembled a Citigrade
(therefore quite different from the gossamer), while standing on the
summit of a post, darted forth four or five threads from its spinners.
These, glittering in the sunshine, might be compared to diverging rays
of light; they were not, however, straight, but in undulations like
films of silk blown by the wind.  They were more than a yard in length,
and diverged in an ascending direction from the orifices.  The spider
then suddenly let go its hold of the post, and was quickly borne out of
sight.  The day was hot and apparently calm; yet under such
circumstances, the atmosphere can never be so tranquil as not to affect
a vane so delicate as the thread of a spider's web.  If during a warm
day we look either at the shadow of any object cast on a bank, or over
a level plain at a distant landmark, the effect of an ascending current
of heated air is almost always evident: such upward currents, it has
been remarked, are also shown by the ascent of soap-bubbles, which will
not rise in an in-doors room.  Hence I think there is not much
difficulty in understanding the ascent of the fine lines projected from
a spider's spinners, and afterwards of the spider itself; the
divergence of the lines has been attempted to be explained, I believe
by Mr. Murray, by their similar electrical condition. The circumstance
of spiders of the same species, but of different sexes and ages, being
found on several occasions at the distance of many leagues from the
land, attached in vast numbers to the lines, renders it probable that
the habit of sailing through the air is as characteristic of this
tribe, as that of diving is of the Argyroneta.  We may then reject
Latreille's supposition, that the gossamer owes its origin
indifferently to the young of several genera of spiders: although, as
we have seen, the young of other spiders do possess the power of
performing aerial voyages. [7]

During our different passages south of the Plata, I often towed astern
a net made of bunting, and thus caught many curious animals.  Of
Crustacea there were many strange and undescribed genera.  One, which
in some respects is allied to the Notopods (or those crabs which have
their posterior legs placed almost on their backs, for the purpose of
adhering to the under side of rocks), is very remarkable from the
structure of its hind pair of legs.  The penultimate joint, instead of
terminating in a simple claw, ends in three bristle-like appendages of
dissimilar lengths--the longest equalling that of the entire leg. These
claws are very thin, and are serrated with the finest teeth, directed
backwards: their curved extremities are flattened, and on this part
five most minute cups are placed which seem to act in the same manner
as the suckers on the arms of the cuttle-fish.  As the animal lives in
the open sea, and probably wants a place of rest, I suppose this
beautiful and most anomalous structure is adapted to take hold of
floating marine animals.

In deep water, far from the land, the number of living creatures is
extremely small: south of the latitude 35 degs., I never succeeded in
catching anything besides some beroe, and a few species of minute
entomostracous crustacea. In shoaler water, at the distance of a few
miles from the coast, very many kinds of crustacea and some other
animals are numerous, but only during the night.  Between latitudes 56
and 57 degs. south of Cape Horn, the net was put astern several times;
it never, however, brought up anything besides a few of two extremely
minute species of Entomostraca. Yet whales and seals, petrels and
albatross, are exceedingly abundant throughout this part of the ocean.
It has always been a mystery to me on what the albatross, which lives
far from the shore, can subsist; I presume that, like the condor, it is
able to fast long; and that one good feast on the carcass of a putrid
whale lasts for a long time.  The central and intertropical parts of
the Atlantic swarm with Pteropoda, Crustacea, and Radiata, and with
their devourers the flying-fish, and again with their devourers the
bonitos and albicores; I presume that the numerous lower pelagic
animals feed on the Infusoria, which are now known, from the researches
of Ehrenberg, to abound in the open ocean: but on what, in the clear
blue water, do these Infusoria subsist?

While sailing a little south of the Plata on one very dark night, the
sea presented a wonderful and most beautiful spectacle.  There was a
fresh breeze, and every part of the surface, which during the day is
seen as foam, now glowed with a pale light.  The vessel drove before
her bows two billows of liquid phosphorus, and in her wake she was
followed by a milky train.  As far as the eye reached, the crest of
every wave was bright, and the sky above the horizon, from the
reflected glare of these livid flames, was not so utterly obscure as
over the vault of the heavens.

As we proceed further southward the sea is seldom phosphorescent; and
off Cape Horn I do not recollect more than once having seen it so, and
then it was far from being brilliant.  This circumstance probably has a
close connection with the scarcity of organic beings in that part of
the ocean. After the elaborate paper, [8] by Ehrenberg, on the
phosphorescence of the sea, it is almost superfluous on my part to make
any observations on the subject.  I may however add, that the same torn
and irregular particles of gelatinous matter, described by Ehrenberg,
seem in the southern as well as in the northern hemisphere, to be the
common cause of this phenomenon.  The particles were so minute as
easily to pass through fine gauze; yet many were distinctly visible by
the naked eye.  The water when placed in a tumbler and agitated, gave
out sparks, but a small portion in a watch-glass scarcely ever was
luminous.  Ehrenberg states that these particles all retain a certain
degree of irritability.  My observations, some of which were made
directly after taking up the water, gave a different result.  I may
also mention, that having used the net during one night, I allowed it
to become partially dry, and having occasion twelve hours afterwards to
employ it again, I found the whole surface sparkled as brightly as when
first taken out of the water. It does not appear probable in this case,
that the particles could have remained so long alive.  On one occasion
having kept a jelly-fish of the genus Dianaea till it was dead, the
water in which it was placed became luminous.  When the waves
scintillate with bright green sparks, I believe it is generally owing
to minute crustacea.  But there can be no doubt that very many other
pelagic animals, when alive, are phosphorescent.

On two occasions I have observed the sea luminous at considerable
depths beneath the surface.  Near the mouth of the Plata some circular
and oval patches, from two to four yards in diameter, and with defined
outlines, shone with a steady but pale light; while the surrounding
water only gave out a few sparks.  The appearance resembled the
reflection of the moon, or some luminous body; for the edges were
sinuous from the undulations of the surface.  The ship, which drew
thirteen feet of water, passed over, without disturbing these patches.
Therefore we must suppose that some animals were congregated together
at a greater depth than the bottom of the vessel.

Near Fernando Noronha the sea gave out light in flashes. The appearance
was very similar to that which might be expected from a large fish
moving rapidly through a luminous fluid.  To this cause the sailors
attributed it; at the time, however, I entertained some doubts, on
account of the frequency and rapidity of the flashes.  I have already
remarked that the phenomenon is very much more common in warm than in
cold countries; and I have sometimes imagined that a disturbed
electrical condition of the atmosphere was most favourable to its
production.  Certainly I think the sea is most luminous after a few
days of more calm weather than ordinary, during which time it has
swarmed with various animals.  Observing that the water charged with
gelatinous particles is in an impure state, and that the luminous
appearance in all common cases is produced by the agitation of the
fluid in contact with the atmosphere, I am inclined to consider that
the phosphorescence is the result of the decomposition of the organic
particles, by which process (one is tempted almost to call it a kind of
respiration) the ocean becomes purified.

December 23rd.--We arrived at Port Desire, situated in lat. 47 degs.,
on the coast of Patagonia.  The creek runs for about twenty miles
inland, with an irregular width.  The Beagle anchored a few miles
within the entrance, in front of the ruins of an old Spanish settlement.

The same evening I went on shore.  The first landing in any new country
is very interesting, and especially when, as in this case, the whole
aspect bears the stamp of a marked and individual character.  At the
height of between two and three hundred feet above some masses of
porphyry a wide plain extends, which is truly characteristic of
Patagonia. The surface is quite level, and is composed of well-rounded
shingle mixed with a whitish earth.  Here and there scattered tufts of
brown wiry grass are supported, and still more rarely, some low thorny
bushes.  The weather is dry and pleasant, and the fine blue sky is but
seldom obscured.  When standing in the middle of one of these desert
plains and looking towards the interior, the view is generally bounded
by the escarpment of another plain, rather higher, but equally level
and desolate; and in every other direction the horizon is indistinct
from the trembling mirage which seems to rise from the heated surface.

In such a country the fate of the Spanish settlement was soon decided;
the dryness of the climate during the greater part of the year, and the
occasional hostile attacks of the wandering Indians, compelled the
colonists to desert their half-finished buildings.  The style, however,
in which they were commenced shows the strong and liberal hand of Spain
in the old time.  The result of all the attempts to colonize this side
of America south of 41 degs., has been miserable.  Port Famine
expresses by its name the lingering and extreme sufferings of several
hundred wretched people, of whom one alone survived to relate their
misfortunes.  At St. Joseph's Bay, on the coast of Patagonia, a small
settlement was made; but during one Sunday the Indians made an attack
and massacred the whole party, excepting two men, who remained captives
during many years.  At the Rio Negro I conversed with one of these men,
now in extreme old age.

The zoology of Patagonia is as limited as its flora. [9] On the arid
plains a few black beetles (Heteromera) might be seen slowly crawling
about, and occasionally a lizard darted from side to side.  Of birds we
have three carrion hawks and in the valleys a few finches and
insect-feeders.  An ibis (Theristicus melanops--a species said to be
found in central Africa) is not uncommon on the most desert parts: in
their stomachs I found grasshoppers, cicadae, small lizards, and even
scorpions. [10] At one time of the year these birds go in flocks, at
another in pairs, their cry is very loud and singular, like the
neighing of the guanaco.

The guanaco, or wild llama, is the characteristic quadruped of the
plains of Patagonia; it is the South American representative of the
camel of the East.  It is an elegant animal in a state of nature, with
a long slender neck and fine legs.  It is very common over the whole of
the temperate parts of the continent, as far south as the islands near
Cape Horn.  It generally lives in small herds of from half a dozen to
thirty in each; but on the banks of the St. Cruz we saw one herd which
must have contained at least five hundred.

They are generally wild and extremely wary.  Mr. Stokes told me, that
he one day saw through a glass a herd of these animals which evidently
had been frightened, and were running away at full speed, although
their distance was so great that he could not distinguish them with his
naked eye.  The sportsman frequently receives the first notice of their
presence, by hearing from a long distance their peculiar shrill
neighing note of alarm.  If he then looks attentively, he will probably
see the herd standing in a line on the side of some distant hill.  On
approaching nearer, a few more squeals are given, and off they set at
an apparently slow, but really quick canter, along some narrow beaten
track to a neighbouring hill.  If, however, by chance he abruptly meets
a single animal, or several together, they will generally stand
motionless and intently gaze at him; then perhaps move on a few yards,
turn round, and look again.  What is the cause of this difference in
their shyness?  Do they mistake a man in the distance for their chief
enemy the puma?  Or does curiosity overcome their timidity?  That they
are curious is certain; for if a person lies on the ground, and plays
strange antics, such as throwing up his feet in the air, they will
almost always approach by degrees to reconnoitre him.  It was an
artifice that was repeatedly practised by our sportsmen with success,
and it had moreover the advantage of allowing several shots to be
fired, which were all taken as parts of the performance.  On the
mountains of Tierra del Fuego, I have more than once seen a guanaco, on
being approached, not only neigh and squeal, but prance and leap about
in the most ridiculous manner, apparently in defiance as a challenge.
These animals are very easily domesticated, and I have seen some thus
kept in northern Patagonia near a house, though not under any
restraint.  They are in this state very bold, and readily attack a man
by striking him from behind with both knees.  It is asserted that the
motive for these attacks is jealousy on account of their females.  The
wild guanacos, however, have no idea of defence; even a single dog will
secure one of these large animals, till the huntsman can come up.  In
many of their habits they are like sheep in a flock. Thus when they see
men approaching in several directions on horseback, they soon become
bewildered, and know not which way to run.  This greatly facilitates
the Indian method of hunting, for they are thus easily driven to a
central point, and are encompassed.

The guanacos readily take to the water: several times at Port Valdes
they were seen swimming from island to island. Byron, in his voyage
says he saw them drinking salt water. Some of our officers likewise saw
a herd apparently drinking the briny fluid from a salina near Cape
Blanco.  I imagine in several parts of the country, if they do not
drink salt water, they drink none at all.  In the middle of the day
they frequently roll in the dust, in saucer-shaped hollows.  The males
fight together; two one day passed quite close to me, squealing and
trying to bite each other; and several were shot with their hides
deeply scored.  Herds sometimes appear to set out on exploring parties:
at Bahia Blanca, where, within thirty miles of the coast, these animals
are extremely unfrequent, I one day saw the tracks of thirty or forty,
which had come in a direct line to a muddy salt-water creek.  They then
must have perceived that they were approaching the sea, for they had
wheeled with the regularity of cavalry, and had returned back in as
straight a line as they had advanced. The guanacos have one singular
habit, which is to me quite inexplicable; namely, that on successive
days they drop their dung in the same defined heap.  I saw one of these
heaps which was eight feet in diameter, and was composed of a large
quantity.  This habit, according to M. A. d'Orbigny, is common to all
the species of the genus; it is very useful to the Peruvian Indians,
who use the dung for fuel, and are thus saved the trouble of collecting
it.

The guanacos appear to have favourite spots for lying down to die.  On
the banks of the St. Cruz, in certain circumscribed spaces, which were
generally bushy and all near the river, the ground was actually white
with bones.  On one such spot I counted between ten and twenty heads. I
particularly examined the bones; they did not appear, as some scattered
ones which I had seen, gnawed or broken, as if dragged together by
beasts of prey.  The animals in most cases must have crawled, before
dying, beneath and amongst the bushes.  Mr. Bynoe informs me that
during a former voyage he observed the same circumstance on the banks
of the Rio Gallegos.  I do not at all understand the reason of this,
but I may observe, that the wounded guanacos at the St. Cruz invariably
walked towards the river.  At St. Jago in the Cape de Verd Islands, I
remember having seen in a ravine a retired corner covered with bones of
the goat; we at the time exclaimed that it was the burial ground of all
the goats in the island.  I mention these trifling circumstances,
because in certain cases they might explain the occurrence of a number
of uninjured bones in a cave, or buried under alluvial accumulations;
and likewise the cause why certain animals are more commonly embedded
than others in sedimentary deposits.

One day the yawl was sent under the command of Mr. Chaffers with three
days' provisions to survey the upper part of the harbour.  In the
morning we searched for some watering-places mentioned in an old
Spanish chart.  We found one creek, at the head of which there was a
trickling rill (the first we had seen) of brackish water.  Here the
tide compelled us to wait several hours; and in the interval I walked
some miles into the interior.  The plain as usual consisted of gravel,
mingled with soil resembling chalk in appearance, but very different
from it in nature.  From the softness of these materials it was worn
into many gulleys.  There was not a tree, and, excepting the guanaco,
which stood on the hill-top a watchful sentinel over its herd, scarcely
an animal or a bird.  All was stillness and desolation.  Yet in passing
over these scenes, without one bright object near, an ill-defined but
strong sense of pleasure is vividly excited. One asked how many ages
the plain had thus lasted, and how many more it was doomed thus to
continue.

"None can reply--all seems eternal now. The wilderness has a mysterious
tongue, Which teaches awful doubt." [11]

In the evening we sailed a few miles further up, and then pitched the
tents for the night.  By the middle of the next day the yawl was
aground, and from the shoalness of the water could not proceed any
higher.  The water being found partly fresh, Mr. Chaffers took the
dingey and went up two or three miles further, where she also grounded,
but in a fresh-water river.  The water was muddy, and though the stream
was most insignificant in size, it would be difficult to account for
its origin, except from the melting snow on the Cordillera.  At the
spot where we bivouacked, we were surrounded by bold cliffs and steep
pinnacles of porphyry.  I do not think I ever saw a spot which appeared
more secluded from the rest of the world, than this rocky crevice in
the wide plain.

The second day after our return to the anchorage, a party of officers
and myself went to ransack an old Indian grave, which I had found on
the summit of a neighbouring hill. Two immense stones, each probably
weighing at least a couple of tons, had been placed in front of a ledge
of rock about six feet high.  At the bottom of the grave on the hard
rock there was a layer of earth about a foot deep, which must have been
brought up from the plain below.  Above it a pavement of flat stones
was placed, on which others were piled, so as to fill up the space
between the ledge and the two great blocks.  To complete the grave, the
Indians had contrived to detach from the ledge a huge fragment, and to
throw it over the pile so as to rest on the two blocks.  We undermined
the grave on both sides, but could not find any relics, or even bones.
The latter probably had decayed long since (in which case the grave
must have been of extreme antiquity), for I found in another place some
smaller heaps beneath which a very few crumbling fragments could yet be
distinguished as having belonged to a man.  Falconer states, that where
an Indian dies he is buried, but that subsequently his bones are
carefully taken up and carried, let the distance be ever so great, to
be deposited near the sea-coast.  This custom, I think, may be
accounted for by recollecting, that before the introduction of horses,
these Indians must have led nearly the same life as the Fuegians now
do, and therefore generally have resided in the neighbourhood of the
sea. The common prejudice of lying where one's ancestors have lain,
would make the now roaming Indians bring the less perishable part of
their dead to their ancient burial-ground on the coast.

January 9th, 1834.--Before it was dark the Beagle anchored in the fine
spacious harbour of Port St. Julian, situated about one hundred and ten
miles to the south of Port Desire. We remained here eight days. The
country is nearly similar to that of Port Desire, but perhaps rather
more sterile.  One day a party accompanied Captain Fitz Roy on a long
walk round the head of the harbour.  We were eleven hours without
tasting any water, and some of the party were quite exhausted.  From
the summit of a hill (since well named Thirsty Hill) a fine lake was
spied, and two of the party proceeded with concerted signals to show
whether it was fresh water.  What was our disappointment to find a
snow-white expanse of salt, crystallized in great cubes!  We attributed
our extreme thirst to the dryness of the atmosphere; but whatever the
cause might be, we were exceedingly glad late in the evening to get
back to the boats.  Although we could nowhere find, during our whole
visit, a single drop of fresh water, yet some must exist; for by an odd
chance I found on the surface of the salt water, near the head of the
bay, a Colymbetes not quite dead, which must have lived in some not far
distant pool.  Three other insects (a Cincindela, like hybrida, a
Cymindis, and a Harpalus, which all live on muddy flats occasionally
overflowed by the sea), and one other found dead on the plain, complete
the list of the beetles.  A good-sized fly (Tabanus) was extremely
numerous, and tormented us by its painful bite.  The common horsefly,
which is so troublesome in the shady lanes of England, belongs to this
same genus.  We here have the puzzle that so frequently occurs in the
case of musquitoes--on the blood of what animals do these insects
commonly feed?  The guanaco is nearly the only warm-blooded quadruped,
and it is found in quite inconsiderable numbers compared with the
multitude of flies.

The geology of Patagonia is interesting.  Differently from Europe,
where the tertiary formations appear to have accumulated in bays, here
along hundreds of miles of coast we have one great deposit, including
many tertiary shells, all apparently extinct.  The most common shell is
a massive gigantic oyster, sometimes even a foot in diameter.  These
beds are covered by others of a peculiar soft white stone, including
much gypsum, and resembling chalk, but really of a pumiceous nature. It
is highly remarkable, from being composed, to at least one-tenth of its
bulk, of Infusoria. Professor Ehrenberg has already ascertained in it
thirty oceanic forms.  This bed extends for 500 miles along the coast,
and probably for a considerably greater distance.  At Port St. Julian
its thickness is more than 800 feet!  These white beds are everywhere
capped by a mass of gravel, forming probably one of the largest beds of
shingle in the world: it certainly extends from near the Rio Colorado
to between 600 and 700 nautical miles southward, at Santa Cruz (a river
a little south of St. Julian), it reaches to the foot of the
Cordillera; half way up the river, its thickness is more than 200 feet;
it probably everywhere extends to this great chain, whence the
well-rounded pebbles of porphyry have been derived: we may consider its
average breadth as 200 miles, and its average thickness as about 50
feet.  If this great bed of pebbles, without including the mud
necessarily derived from their attrition, was piled into a mound, it
would form a great mountain chain!  When we consider that all these
pebbles, countless as the grains of sand in the desert, have been
derived from the slow falling of masses of rock on the old coast-lines
and banks of rivers, and that these fragments have been dashed into
smaller pieces, and that each of them has since been slowly rolled,
rounded, and far transported the mind is stupefied in thinking over the
long, absolutely necessary, lapse of years.  Yet all this gravel has
been transported, and probably rounded, subsequently to the deposition
of the white beds, and long subsequently to the underlying beds with
the tertiary shells.

Everything in this southern continent has been effected on a grand
scale: the land, from the Rio Plata to Tierra del Fuego, a distance of
1200 miles, has been raised in mass (and in Patagonia to a height of
between 300 and 400 feet), within the period of the now existing
sea-shells.  The old and weathered shells left on the surface of the
upraised plain still partially retain their colours.  The uprising
movement has been interrupted by at least eight long periods of rest,
during which the sea ate, deeply back into the land, forming at
successive levels the long lines of cliffs, or escarpments, which
separate the different plains as they rise like steps one behind the
other.  The elevatory movement, and the eating-back power of the sea
during the periods of rest, have been equable over long lines of coast;
for I was astonished to find that the step-like plains stand at nearly
corresponding heights at far distant points.  The lowest plain is 90
feet high; and the highest, which I ascended near the coast, is 950
feet; and of this, only relics are left in the form of flat
gravel-capped hills.  The upper plain of Santa Cruz slopes up to a
height of 3000 feet at the foot of the Cordillera.  I have said that
within the period of existing sea-shells, Patagonia has been upraised
300 to 400 feet: I may add, that within the period when icebergs
transported boulders over the upper plain of Santa Cruz, the elevation
has been at least 1500 feet.  Nor has Patagonia been affected only by
upward movements: the extinct tertiary shells from Port St. Julian and
Santa Cruz cannot have lived, according to Professor E. Forbes, in a
greater depth of water than from 40 to 250 feet; but they are now
covered with sea-deposited strata from 800 to 1000 feet in thickness:
hence the bed of the sea, on which these shells once lived, must have
sunk downwards several hundred feet, to allow of the accumulation of
the superincumbent strata.  What a history of geological changes does
the simply-constructed coast of Patagonia reveal!

At Port St. Julian, [12] in some red mud capping the gravel on the
90-feet plain, I found half the skeleton of the Macrauchenia
Patachonica, a remarkable quadruped, full as large as a camel.  It
belongs to the same division of the Pachydermata with the rhinoceros,
tapir, and palaeotherium; but in the structure of the bones of its long
neck it shows a clear relation to the camel, or rather to the guanaco
and llama. From recent sea-shells being found on two of the higher
step-formed plains, which must have been modelled and upraised before
the mud was deposited in which the Macrauchenia was entombed, it is
certain that this curious quadruped lived long after the sea was
inhabited by its present shells.  I was at first much surprised how a
large quadruped could so lately have subsisted, in lat. 49 degs. 15',
on these wretched gravel plains, with their stunted vegetation; but the
relationship of the Macrauchenia to the Guanaco, now an inhabitant of
the most sterile parts, partly explains this difficulty.

The relationship, though distant, between the Macrauchenia and the
Guanaco, between the Toxodon and the Capybara,--the closer relationship
between the many extinct Edentata and the living sloths, ant-eaters,
and armadillos, now so eminently characteristic of South American
zoology,--and the still closer relationship between the fossil and
living species of Ctenomys and Hydrochaerus, are most interesting
facts.  This relationship is shown wonderfully--as wonderfully as
between the fossil and extinct Marsupial animals of Australia--by the
great collection lately brought to Europe from the caves of Brazil by
MM. Lund and Clausen. In this collection there are extinct species of
all the thirty-two genera, excepting four, of the terrestrial
quadrupeds now inhabiting the provinces in which the caves occur; and
the extinct species are much more numerous than those now living: there
are fossil ant-eaters, armadillos, tapirs, peccaries, guanacos,
opossums, and numerous South American gnawers and monkeys, and other
animals.  This wonderful relationship in the same continent between the
dead and the living, will, I do not doubt, hereafter throw more light
on the appearance of organic beings on our earth, and their
disappearance from it, than any other class of facts.

It is impossible to reflect on the changed state of the American
continent without the deepest astonishment.  Formerly it must have
swarmed with great monsters: now we find mere pigmies, compared with
the antecedent, allied races.  If Buffon had known of the gigantic
sloth and armadillo-like animals, and of the lost Pachydermata, he
might have said with a greater semblance of truth that the creative
force in America had lost its power, rather than that it had never
possessed great vigour.  The greater number, if not all, of these
extinct quadrupeds lived at a late period, and were the contemporaries
of most of the existing sea-shells.  Since they lived, no very great
change in the form of the land can have taken place.  What, then, has
exterminated so many species and whole genera?  The mind at first is
irresistibly hurried into the belief of some great catastrophe; but
thus to destroy animals, both large and small, in Southern Patagonia,
in Brazil, on the Cordillera of Peru, in North America up to Behring's
Straits, we must shake the entire framework of the globe.  An
examination, moreover, of the geology of La Plata and Patagonia, leads
to the belief that all the features of the land result from slow and
gradual changes.  It appears from the character of the fossils in
Europe, Asia, Australia, and in North and South America, that those
conditions which favour the life of the _larger_ quadrupeds were lately
co-extensive with the world: what those conditions were, no one has yet
even conjectured.  It could hardly have been a change of temperature,
which at about the same time destroyed the inhabitants of tropical,
temperate, and arctic latitudes on both sides of the globe.  In North
America we positively know from Mr. Lyell, that the large quadrupeds
lived subsequently to that period, when boulders were brought into
latitudes at which icebergs now never arrive: from conclusive but
indirect reasons we may feel sure, that in the southern hemisphere the
Macrauchenia, also, lived long subsequently to the ice-transporting
boulder-period.  Did man, after his first inroad into South America,
destroy, as has been suggested, the unwieldy Megatherium and the other
Edentata?  We must at least look to some other cause for the
destruction of the little tucutuco at Bahia Blanca, and of the many
fossil mice and other small quadrupeds in Brazil.  No one will imagine
that a drought, even far severer than those which cause such losses in
the provinces of La Plata, could destroy every individual of every
species from Southern Patagonia to Behring's Straits.  What shall we
say of the extinction of the horse?  Did those plains fail of pasture,
which have since been overrun by thousands and hundreds of thousands of
the descendants of the stock introduced by the Spaniards?  Have the
subsequently introduced species consumed the food of the great
antecedent races? Can we believe that the Capybara has taken the food
of the Toxodon, the Guanaco of the Macrauchenia, the existing small
Edentata of their numerous gigantic prototypes?  Certainly, no fact in
the long history of the world is so startling as the wide and repeated
exterminations of its inhabitants.

Nevertheless, if we consider the subject under another point of view,
it will appear less perplexing.  We do not steadily bear in mind, how
profoundly ignorant we are of the conditions of existence of every
animal; nor do we always remember, that some check is constantly
preventing the too rapid increase of every organized being left in a
state of nature.  The supply of food, on an average, remains constant,
yet the tendency in every animal to increase by propagation is
geometrical; and its surprising effects have nowhere been more
astonishingly shown, than in the case of the European animals run wild
during the last few centuries in America. Every animal in a state of
nature regularly breeds; yet in a species long established, any _great_
increase in numbers is obviously impossible, and must be checked by
some means. We are, nevertheless, seldom able with certainty to tell in
any given species, at what period of life, or at what period of the
year, or whether only at long intervals, the check falls; or, again,
what is the precise nature of the check. Hence probably it is, that we
feel so little surprise at one, of two species closely allied in
habits, being rare and the other abundant in the same district; or,
again, that one should be abundant in one district, and another,
filling the same place in the economy of nature, should be abundant in
a neighbouring district, differing very little in its conditions.  If
asked how this is, one immediately replies that it is determined by
some slight difference, in climate, food, or the number of enemies: yet
how rarely, if ever, we can point out the precise cause and manner of
action of the check!  We are therefore, driven to the conclusion, that
causes generally quite inappreciable by us, determine whether a given
species shall be abundant or scanty in numbers.

In the cases where we can trace the extinction of a species through
man, either wholly or in one limited district, we know that it becomes
rarer and rarer, and is then lost: it would be difficult to point out
any just distinction [13] between a species destroyed by man or by the
increase of its natural enemies.  The evidence of rarity preceding
extinction, is more striking in the successive tertiary strata, as
remarked by several able observers; it has often been found that a
shell very common in a tertiary stratum is now most rare, and has even
long been thought extinct.  If then, as appears probable, species first
become rare and then extinct--if the too rapid increase of every
species, even the most favoured, is steadily checked, as we must admit,
though how and when it is hard to say--and if we see, without the
smallest surprise, though unable to assign the precise reason, one
species abundant and another closely allied species rare in the same
district--why should we feel such great astonishment at the rarity
being carried one step further to extinction?  An action going on, on
every side of us, and yet barely appreciable, might surely be carried a
little further, without exciting our observation. Who would feel any
great surprise at hearing that the Magalonyx was formerly rare compared
with the Megatherium, or that one of the fossil monkeys was few in
number compared with one of the now living monkeys? and yet in this
comparative rarity, we should have the plainest evidence of less
favourable conditions for their existence.  To admit that species
generally become rare before they become extinct--to feel no surprise
at the comparative rarity of one species with another, and yet to call
in some extraordinary agent and to marvel greatly when a species ceases
to exist, appears to me much the same as to admit that sickness in the
individual is the prelude to death--to feel no surprise at
sickness--but when the sick man dies to wonder, and to believe that he
died through violence.

[1] Mr. Waterhouse has drawn up a detailed description of this head,
which I hope he will publish in some Journal.

[2] A nearly similar abnormal, but I do not know whether hereditary,
structure has been observed in the carp, and likewise in the crocodile
of the Ganges: Histoire des Anomalies, par M. Isid. Geoffroy St.
Hilaire, tom. i. p. 244.

[3] M. A. d'Orbigny has given nearly a similar account of these dogs,
tom. i. p. 175.

[4] I must express my obligations to Mr. Keane, at whose house I was
staying on the Berquelo, and to Mr. Lumb at Buenos Ayres, for without
their assistance these valuable remains would never have reached
England.

[5] Lyell's Principles of Geology, vol. iii. p. 63.

[6] The flies which frequently accompany a ship for some days on its
passage from harbour to harbour, wandering from the vessel, are soon
lost, and all disappear.

[7] Mr. Blackwall, in his Researches in Zoology, has many excellent
observations on the habits of spiders.

[8] An abstract is given in No. IV. of the Magazine of Zoology and
Botany.

[9] I found here a species of cactus, described by Professor Henslow,
under the name of Opuntia Darwinii (Magazine of Zoology and Botany,
vol. i. p. 466), which was remarkable for the irritability of the
stamens, when I inserted either a piece of stick or the end of my
finger in the flower.  The segments of the perianth also closed on the
pistil, but more slowly than the stamens.  Plants of this family,
generally considered as tropical, occur in North America (Lewis and
Clarke's Travels, p. 221), in the same high latitude as here, namely,
in both cases, in 47 degs.

[10] These insects were not uncommon beneath stones.  I found one
cannibal scorpion quietly devouring another.

[11] Shelley, Lines on Mt. Blanc.

[12] I have lately heard that Capt. Sulivan, R.N., has found numerous
fossil bones, embedded in regular strata, on the banks of the R.
Gallegos, in lat. 51 degs. 4'. Some of the bones are large; others are
small, and appear to have belonged to an armadillo.  This is a most
interesting and important discovery.

[13] See the excellent remarks on this subject by Mr. Lyell, in his
Principles of Geology.



CHAPTER IX

SANTA CRUZ, PATAGONIA, AND THE FALKLAND ISLANDS

Santa Cruz--Expedition up the River--Indians--Immense Streams of
Basaltic Lava--Fragments not transported by the River--Excavations of
the Valley--Condor, Habits of--Cordillera--Erratic Boulders of great
size--Indian Relics--Return to the Ship--Falkland Islands--Wild
Horses, Cattle, Rabbits--Wolf-like Fox--Fire made of Bones--Manner of
Hunting Wild Cattle--Geology--Streams of Stones--Scenes of
Violence--Penguins--Geese--Eggs of Doris--Compound Animals.


APRIL 13, 1834.--The Beagle anchored within the mouth of the Santa
Cruz.  This river is situated about sixty miles south of Port St.
Julian.  During the last voyage Captain Stokes proceeded thirty miles
up it, but then, from the want of provisions, was obliged to return.
Excepting what was discovered at that time, scarcely anything was known
about this large river.  Captain Fitz Roy now determined to follow its
course as far as time would allow.  On the 18th three whale-boats
started, carrying three weeks' provisions; and the party consisted of
twenty-five souls--a force which would have been sufficient to have
defied a host of Indians.  With a strong flood-tide and a fine day we
made a good run, soon drank some of the fresh water, and were at night
nearly above the tidal influence.

The river here assumed a size and appearance which, even at the highest
point we ultimately reached, was scarcely diminished.  It was generally
from three to four hundred yards broad, and in the middle about
seventeen feet deep.  The rapidity of the current, which in its whole
course runs at the rate of from four to six knots an hour, is perhaps
its most remarkable feature.  The water is of a fine blue colour, but
with a slight milky tinge, and not so transparent as at first sight
would have been expected.  It flows over a bed of pebbles, like those
which compose the beach and the surrounding plains.  It runs in a
winding course through a valley, which extends in a direct line
westward.  This valley varies from five to ten miles in breadth; it is
bounded by step-formed terraces, which rise in most parts, one above
the other, to the height of five hundred feet, and have on the opposite
sides a remarkable correspondence.

April 19th.--Against so strong a current it was, of course, quite
impossible to row or sail: consequently the three boats were fastened
together head and stern, two hands left in each, and the rest came on
shore to track.  As the general arrangements made by Captain Fitz Roy
were very good for facilitating the work of all, and as all had a share
in it, I will describe the system.  The party including every one, was
divided into two spells, each of which hauled at the tracking line
alternately for an hour and a half.  The officers of each boat lived
with, ate the same food, and slept in the same tent with their crew, so
that each boat was quite independent of the others.  After sunset the
first level spot where any bushes were growing, was chosen for our
night's lodging.  Each of the crew took it in turns to be cook.
Immediately the boat was hauled up, the cook made his fire; two others
pitched the tent; the coxswain handed the things out of the boat; the
rest carried them up to the tents and collected firewood.  By this
order, in half an hour everything was ready for the night.  A watch of
two men and an officer was always kept, whose duty it was to look after
the boats, keep up the fire, and guard against Indians. Each in the
party had his one hour every night.

During this day we tracked but a short distance, for there were many
islets, covered by thorny bushes, and the channels between them were
shallow.

April 20th.--We passed the islands and set to work.  Our regular day's
march, although it was hard enough, carried us on an average only ten
miles in a straight line, and perhaps fifteen or twenty altogether.
Beyond the place where we slept last night, the country is completely
_terra incognita_, for it was there that Captain Stokes turned back. We
saw in the distance a great smoke, and found the skeleton of a horse,
so we knew that Indians were in the neighbourhood. On the next morning
(21st) tracks of a party of horse and marks left by the trailing of the
chuzos, or long spears, were observed on the ground. It was generally
thought that the Indians had reconnoitred us during the night. Shortly
afterwards we came to a spot where, from the fresh footsteps of men,
children, and horses, it was evident that the party had crossed the
river.

April 22nd.--The country remained the same, and was extremely
uninteresting.  The complete similarity of the productions throughout
Patagonia is one of its most striking characters.  The level plains of
arid shingle support the same stunted and dwarf plants; and in the
valleys the same thorn-bearing bushes grow.  Everywhere we see the same
birds and insects.  Even the very banks of the river and of the clear
streamlets which entered it, were scarcely enlivened by a brighter tint
of green.  The curse of sterility is on the land, and the water flowing
over a bed of pebbles partakes of the same curse.  Hence the number of
water-fowls is very scanty; for there is nothing to support life in the
stream of this barren river.

Patagonia, poor as she is in some respects, can however boast of a
greater stock of small rodents [1] than perhaps any other country in
the world.  Several species of mice are externally characterized by
large thin ears and a very fine fur.  These little animals swarm
amongst the thickets in the valleys, where they cannot for months
together taste a drop of water excepting the dew.  They all seem to be
cannibals for no sooner was a mouse caught in one of my traps that it
was devoured by others.  A small and delicately shaped fox, which is
likewise very abundant, probably derives its entire support from these
small animals.  The guanaco is also in his proper district, herds of
fifty or a hundred were common; and, as I have stated, we saw one which
must have contained at least five hundred.  The puma, with the condor
and other carrion-hawks in its train, follows and preys upon these
animals.  The footsteps of the puma were to be seen almost everywhere
on the banks of the river; and the remains of several guanacos, with
their necks dislocated and bones broken, showed how they had met their
death.

April 24th.--Like the navigators of old when approaching an unknown
land, we examined and watched for the most trivial sign of a change.
The drifted trunk of a tree, or a boulder of primitive rock, was hailed
with joy, as if we had seen a forest growing on the flanks of the
Cordillera.  The top, however, of a heavy bank of clouds, which
remained almost constantly in one position, was the most promising
sign, and eventually turned out a true harbinger.  At first the clouds
were mistaken for the mountains themselves, instead of the masses of
vapour condensed by their icy summits.

April 26th.--We this day met with a marked change in the geological
structure of the plains.  From the first starting I had carefully
examined the gravel in the river, and for the two last days had noticed
the presence of a few small pebbles of a very cellular basalt.  These
gradually increased in number and in size, but none were as large as a
man's head.  This morning, however, pebbles of the same rock, but more
compact, suddenly became abundant, and in the course of half an hour we
saw, at the distance of five of six miles, the angular edge of a great
basaltic platform. When we arrived at its base we found the stream
bubbling among the fallen blocks.  For the next twenty-eight miles the
river-course was encumbered with these basaltic masses. Above that
limit immense fragments of primitive rocks, derived from its
surrounding boulder-formation, were equally numerous.  None of the
fragments of any considerable size had been washed more than three or
four miles down the river below their parent-source: considering the
singular rapidity of the great body of water in the Santa Cruz, and
that no still reaches occur in any part, this example is a most
striking one, of the inefficiency of rivers in transporting even
moderately-sized fragments.

The basalt is only lava, which has flowed beneath the sea; but the
eruptions must have been on the grandest scale.  At the point where we
first met this formation it was 120 feet in thickness; following up the
river course, the surface imperceptibly rose and the mass became
thicker, so that at forty miles above the first station it was 320 feet
thick. What the thickness may be close to the Cordillera, I have no
means of knowing, but the platform there attains a height of about
three thousand feet above the level of the sea; we must therefore look
to the mountains of that great chain for its source; and worthy of such
a source are streams that have flowed over the gently inclined bed of
the sea to a distance of one hundred miles.  At the first glance of the
basaltic cliffs on the opposite sides of the valley, it was evident
that the strata once were united.  What power, then, has removed along
a whole line of country, a solid mass of very hard rock, which had an
average thickness of nearly three hundred feet, and a breadth varying
from rather less than two miles to four miles?  The river, though it
has so little power in transporting even inconsiderable fragments, yet
in the lapse of ages might produce by its gradual erosion an effect of
which it is difficult to judge the amount.  But in this case,
independently of the insignificance of such an agency, good reasons can
be assigned for believing that this valley was formerly occupied by an
arm of the sea.  It is needless in this work to detail the arguments
leading to this conclusion, derived from the form and the nature of the
step-formed terraces on both sides of the valley, from the manner in
which the bottom of the valley near the Andes expands into a great
estuary-like plain with sand-hillocks on it, and from the occurrence of
a few sea-shells lying in the bed of the river.  If I had space I could
prove that South America was formerly here cut off by a strait, joining
the Atlantic and Pacific oceans, like that of Magellan. But it may yet
be asked, how has the solid basalt been moved?  Geologists formerly
would have brought into play the violent action of some overwhelming
debacle; but in this case such a supposition would have been quite
inadmissible, because, the same step-like plains with existing
sea-shells lying on their surface, which front the long line of the
Patagonian coast, sweep up on each side of the valley of Santa Cruz. No
possible action of any flood could thus have modelled the land, either
within the valley or along the open coast; and by the formation of such
step-like plains or terraces the valley itself had been hollowed out.
Although we know that there are tides, which run within the Narrows of
the Strait of Magellan at the rate of eight knots an hour, yet we must
confess that it makes the head almost giddy to reflect on the number of
years, century after century, which the tides, unaided by a heavy surf,
must have required to have corroded so vast an area and thickness of
solid basaltic lava.  Nevertheless, we must believe that the strata
undermined by the waters of this ancient strait, were broken up into
huge fragments, and these lying scattered on the beach were reduced
first to smaller blocks, then to pebbles and lastly to the most
impalpable mud, which the tides drifted far into the Eastern or Western
Ocean.

With the change in the geological structure of the plains the character
of the landscape likewise altered.  While rambling up some of the
narrow and rocky defiles, I could almost have fancied myself
transported back again to the barren valleys of the island of St. Jago.
Among the basaltic cliffs I found some plants which I had seen nowhere
else, but others I recognised as being wanderers from Tierra del Fuego.
These porous rocks serve as a reservoir for the scanty rain-water; and
consequently on the line where the igneous and sedimentary formations
unite, some small springs (most rare occurrences in Patagonia) burst
forth; and they could be distinguished at a distance by the
circumscribed patches of bright green herbage.

April 27th.--The bed of the river became rather narrower and hence the
stream more rapid.  It here ran at the rate of six knots an hour. From
this cause, and from the many great angular fragments, tracking the
boats became both dangerous and laborious.


This day I shot a condor.  It measured from tip to tip of the wings,
eight and a half feet, and from beak to tail, four feet.  This bird is
known to have a wide geographical range, being found on the west coast
of South America, from the Strait of Magellan along the Cordillera as
far as eight degrees north of the equator.  The steep cliff near the
mouth of the Rio Negro is its northern limit on the Patagonian coast;
and they have there wandered about four hundred miles from the great
central line of their habitations in the Andes.  Further south, among
the bold precipices at the head of Port Desire, the condor is not
uncommon; yet only a few stragglers occasionally visit the sea-coast. A
line of cliff near the mouth of the Santa Cruz is frequented by these
birds, and about eighty miles up the river, where the sides of the
valley are formed by steep basaltic precipices, the condor reappears.
From these facts it seems that the condors require perpendicular
cliffs.  In Chile, they haunt, during the greater part of the year, the
lower country near the shores of the Pacific, and at night several
roost together in one tree; but in the early part of summer, they
retire to the most inaccessible parts of the inner Cordillera, there to
breed in peace.

With respect to their propagation, I was told by the country people in
Chile, that the condor makes no sort of nest, but in the months of
November and December lays two large white eggs on a shelf of bare
rock.  It is said that the young condors cannot fly for an entire year;
and long after they are able, they continue to roost by night, and hunt
by day with their parents.  The old birds generally live in pairs; but
among the inland basaltic cliffs of the Santa Cruz, I found a spot,
where scores must usually haunt.  On coming suddenly to the brow of the
precipice, it was a grand spectacle to see between twenty and thirty of
these great birds start heavily from their resting-place, and wheel
away in majestic circles.  From the quantity of dung on the rocks they
must long have frequented this cliff for roosting and breeding.  Having
gorged themselves with carrion on the plains below, they retire to
these favourite ledges to digest their food.  From these facts, the
condor, like the gallinazo, must to a certain degree be considered as a
gregarious bird. In this part of the country they live altogether on
the guanacos which have died a natural death, or as more commonly
happens, have been killed by the pumas.  I believe, from what I saw in
Patagonia, that they do not on ordinary occasions extend their daily
excursions to any great distance from their regular sleeping-places.

The condors may oftentimes be seen at a great height, soaring over a
certain spot in the most graceful circles. On some occasions I am sure
that they do this only for pleasure, but on others, the Chileno
countryman tells you that they are watching a dying animal, or the puma
devouring its prey.  If the condors glide down, and then suddenly all
rise together, the Chileno knows that it is the puma which, watching
the carcass, has sprung out to drive away the robbers.  Besides feeding
on carrion, the condors frequently attack young goats and lambs; and
the shepherd-dogs are trained, whenever they pass over, to run out, and
looking upwards to bark violently.  The Chilenos destroy and catch
numbers.  Two methods are used; one is to place a carcass on a level
piece of ground within an enclosure of sticks with an opening, and when
the condors are gorged to gallop up on horseback to the entrance, and
thus enclose them: for when this bird has not space to run, it cannot
give its body sufficient momentum to rise from the ground. The second
method is to mark the trees in which, frequently to the number of five
or six together, they roost, and they at night to climb up and noose
them.  They are such heavy sleepers, as I have myself witnessed, that
this is not a difficult task.  At Valparaiso, I have seen a living
condor sold for sixpence, but the common price is eight or ten
shillings. One which I saw brought in, had been tied with rope, and was
much injured; yet, the moment the line was cut by which its bill was
secured, although surrounded by people, it began ravenously to tear a
piece of carrion.  In a garden at the same place, between twenty and
thirty were kept alive. They were fed only once a week, but they
appeared in pretty good health. [2] The Chileno countrymen assert that
the condor will live, and retain its vigour, between five and six weeks
without eating: I cannot answer for the truth of this, but it is a
cruel experiment, which very likely has been tried.

When an animal is killed in the country, it is well known that the
condors, like other carrion-vultures, soon gain intelligence of it, and
congregate in an inexplicable manner. In most cases it must not be
overlooked, that the birds have discovered their prey, and have picked
the skeleton clean, before the flesh is in the least degree tainted.
Remembering the experiments of M. Audubon, on the little smelling
powers of carrion-hawks, I tried in the above mentioned garden the
following experiment: the condors were tied, each by a rope, in a long
row at the bottom of a wall; and having folded up a piece of meat in
white paper, I walked backwards and forwards, carrying it in my hand at
the distance of about three yards from them, but no notice whatever was
taken.  I then threw it on the ground, within one yard of an old male
bird; he looked at it for a moment with attention, but then regarded it
no more.  With a stick I pushed it closer and closer, until at last he
touched it with his beak; the paper was then instantly torn off with
fury, and at the same moment, every bird in the long row began
struggling and flapping its wings.  Under the same circumstances, it
would have been quite impossible to have deceived a dog.  The evidence
in favour of and against the acute smelling powers of carrion-vultures
is singularly balanced. Professor Owen has demonstrated that the
olfactory nerves of the turkey-buzzard (Cathartes aura) are highly
developed, and on the evening when Mr. Owen's paper was read at the
Zoological Society, it was mentioned by a gentleman that he had seen
the carrion-hawks in the West Indies on two occasions collect on the
roof of a house, when a corpse had become offensive from not having
been buried, in this case, the intelligence could hardly have been
acquired be sight.  On the other hand, besides the experiments of
Audubon and that one by myself, Mr. Bachman has tried in the United
States many varied plans, showing that neither the turkey-buzzard (the
species dissected by Professor Owen) nor the gallinazo find their food
by smell.  He covered portions of highly-offensive offal with a thin
canvas cloth, and strewed pieces of meat on it: these the
carrion-vultures ate up, and then remained quietly standing, with their
beaks within the eighth of an inch of the putrid mass, without
discovering it.  A small rent was made in the canvas, and the offal was
immediately discovered; the canvas was replaced by a fresh piece, and
meat again put on it, and was again devoured by the vultures without
their discovering the hidden mass on which they were trampling.  These
facts are attested by the signatures of six gentlemen, besides that of
Mr. Bachman. [3]

Often when lying down to rest on the open plains, on looking upwards, I
have seen carrion-hawks sailing through the air at a great height.
Where the country is level I do not believe a space of the heavens, of
more than fifteen degrees above the horizon, is commonly viewed with
any attention by a person either walking or on horseback.  If such be
the case, and the vulture is on the wing at a height of between three
and four thousand feet, before it could come within the range of
vision, its distance in a straight line from the beholder's eye, would
be rather more than two British miles.  Might it not thus readily be
overlooked? When an animal is killed by the sportsman in a lonely
valley, may he not all the while be watched from above by the
sharp-sighted bird?  And will not the manner of its descend proclaim
throughout the district to the whole family of carrion-feeders, that
their prey is at hand?

When the condors are wheeling in a flock round and round any spot,
their flight is beautiful.  Except when rising from the ground, I do
not recollect ever having seen one of these birds flap its wings.  Near
Lima, I watched several for nearly half an hour, without once taking
off my eyes, they moved in large curves, sweeping in circles,
descending and ascending without giving a single flap.  As they glided
close over my head, I intently watched from an oblique position, the
outlines of the separate and great terminal feathers of each wing; and
these separate feathers, if there had been the least vibratory
movement, would have appeared as if blended together; but they were
seen distinct against the blue sky.  The head and neck were moved
frequently, and apparently with force; and the extended wings seemed to
form the fulcrum on which the movements of the neck, body, and tail
acted.  If the bird wished to descend, the wings were for a moment
collapsed; and when again expanded with an altered inclination, the
momentum gained by the rapid descent seemed to urge the bird upwards
with the even and steady movement of a paper kite.  In the case of any
bird soaring, its motion must be sufficiently rapid so that the action
of the inclined surface of its body on the atmosphere may
counterbalance its gravity.  The force to keep up the momentum of a
body moving in a horizontal plane in the air (in which there is so
little friction) cannot be great, and this force is all that is wanted.
The movements of the neck and body of the condor, we must suppose, is
sufficient for this.  However this may be, it is truly wonderful and
beautiful to see so great a bird, hour after hour, without any apparent
exertion, wheeling and gliding over mountain and river.

April 29th.--From some high land we hailed with joy the white summits
of the Cordillera, as they were seen occasionally peeping through their
dusky envelope of clouds. During the few succeeding days we continued
to get on slowly, for we found the river-course very tortuous, and
strewed with immense fragments of various ancient slate rocks, and of
granite.  The plain bordering the valley has here attained an elevation
of about 1100 feet above the river, and its character was much altered.
The well-rounded pebbles of porphyry were mingled with many immense
angular fragments of basalt and of primary rocks.  The first of these
erratic boulders which I noticed, was sixty-seven miles distant from
the nearest mountain; another which I measured was five yards square,
and projected five feet above the gravel.  Its edges were so angular,
and its size so great, that I at first mistook it for a rock _in situ_,
and took out my compass to observe the direction of its cleavage.  The
plain here was not quite so level as that nearer the coast, but yet in
betrayed no signs of any great violence.  Under these circumstances it
is, I believe, quite impossible to explain the transportal of these
gigantic masses of rock so many miles from their parent-source, on any
theory except by that of floating icebergs.

During the two last days we met with signs of horses, and with several
small articles which had belonged to the Indians--such as parts of a
mantle and a bunch of ostrich feathers--, but they appeared to have
been lying long on the ground. Between the place where the Indians had
so lately crossed the river and this neighbourhood, though so many
miles apart, the country appears to be quite unfrequented.  At first,
considering the abundance of the guanacos, I was surprised at this; but
it is explained by the stony nature of the plains, which would soon
disable an unshod horse from taking part in the chase.  Nevertheless,
in two places in this very central region, I found small heaps of
stones, which I do not think could have been accidentally thrown
together.  They were placed on points, projecting over the edge of the
highest lava cliff, and they resembled, but on a small scale, those
near Port Desire.

May 4th.--Captain Fitz Roy determined to take the boats no higher. The
river had a winding course, and was very rapid; and the appearance of
the country offered no temptation to proceed any further. Everywhere we
met with the same productions, and the same dreary landscape.  We were
now one hundred and forty miles distant from the Atlantic and about
sixty from the nearest arm of the Pacific.  The valley in this upper
part expanded into a wide basin, bounded on the north and south by the
basaltic platforms, and fronted by the long range of the snow-clad
Cordillera.  But we viewed these grand mountains with regret, for we
were obliged to imagine their nature and productions, instead of
standing, as we had hoped, on their summits. Besides the useless loss
of time which an attempt to ascend the river and higher would have cost
us, we had already been for some days on half allowance of bread. This,
although really enough for reasonable men, was, after a hard day's
march, rather scanty food: a light stomach and an easy digestion are
good things to talk about, but very unpleasant in practice.

5th.--Before sunrise we commenced our descent.  We shot down the stream
with great rapidity, generally at the rate of ten knots an hour. In
this one day we effected what had cost us five-and-a-half hard days'
labour in ascending. On the 8th, we reached the Beagle after our
twenty-one days' expedition.  Every one, excepting myself, had cause to
be dissatisfied; but to me the ascent afforded a most interesting
section of the great tertiary formation of Patagonia.

On March 1st, 1833, and again on March 16th, 1834, the Beagle anchored
in Berkeley Sound, in East Falkland Island. This archipelago is
situated in nearly the same latitude with the mouth of the Strait of
Magellan; it covers a space of one hundred and twenty by sixty
geographical miles, and is little more than half the size of Ireland.
After the possession of these miserable islands had been contested by
France, Spain, and England, they were left uninhabited.  The government
of Buenos Ayres then sold them to a private individual, but likewise
used them, as old Spain had done before, for a penal settlement.
England claimed her right and seized them.  The Englishman who was left
in charge of the flag was consequently murdered.  A British officer was
next sent, unsupported by any power: and when we arrived, we found him
in charge of a population, of which rather more than half were runaway
rebels and murderers.

The theatre is worthy of the scenes acted on it.  An undulating land,
with a desolate and wretched aspect, is everywhere covered by a peaty
soil and wiry grass, of one monotonous brown colour.  Here and there a
peak or ridge of grey quartz rock breaks through the smooth surface
Every one has heard of the climate of these regions; it may be compared
to that which is experienced at the height of between one and two
thousand feet, on the mountains of North Wales; having however less
sunshine and less frost but more wind and rain. [4]

16th.--I will now describe a short excursion which made round a part of
this island.  In the morning I started with six horses and two Gauchos:
the latter were capital men for the purpose, and well accustomed to
living on their own resources.  The weather was very boisterous and
cold with heavy hail-storms.  We got on, however, pretty well but,
except the geology, nothing could be less interesting than our day's
ride.  The country is uniformly the same undulating moorland; the
surface being covered by light brown withered grass and a few very
small shrubs, all springing out of an elastic peaty soil.  In the
valleys here and there might be seen a small flock of wild geese, and
everywhere the ground was so soft that the snipe were able to feed.
Besides these two birds there were few others. There is one main range
of hills, nearly two thousand feet in height, and composed of quartz
rock, the rugged and barren crests of which gave us some trouble to
cross.  On the south side we came to the best country for wild cattle;
we met, however, no great number, for they had been lately much
harassed.

In the evening we came across a small herd.  One of my companions, St.
Jago by name, soon separated a fat cow: he threw the bolas, and it
struck her legs, but failed in becoming entangled.  Then dropping his
hat to mark the spot where the balls were left, while at full gallop,
he uncoiled his lazo, and after a most severe chase, again came up to
the cow, and caught her round the horns.  The other Gaucho had gone on
ahead with the spare horses, so that St. Jago had some difficulty in
killing the furious beast.  He managed to get her on a level piece of
ground, by taking advantage of her as often as she rushed at him; and
when she would not move, my horse, from having been trained, would
canter up, and with his chest give her a violent push.  But when on
level ground it does not appear an easy job for one man to kill a beast
mad with terror.  Nor would it be so, if the horse, when left to itself
without its rider, did not soon learn, for its own safety, to keep the
lazo tight, so that, if the cow or ox moves forward, the horse moves
just as quickly forward; otherwise, it stands motionless leaning on one
side.  This horse, however, was a young one, and would not stand still,
but gave in to the cow as she struggled.  It was admirable to see with
what dexterity St. Jago dodged behind the beast, till at last he
contrived to give the fatal touch to the main tendon of the hind leg
after which, without much difficulty, he drove his knife into the head
of the spinal marrow, and the cow dropped as if struck by lightning. He
cut off pieces of flesh with the skin to it, but without any bones,
sufficient for our expedition.  We then rode on to our sleeping-place,
and had for supper "carne con cuero," or meat roasted with the skin on
it.  This is as superior to common beef as venison is to mutton.  A
large circular piece taken from the back is roasted on the embers with
the hide downwards and is the form of a saucer, so that none of the
gravy is lost. If any worthy alderman had supped with us that evening,
"carne con cuero," without doubt, would soon have been celebrated in
London.

During the night it rained, and the next day (17th) was very stormy,
with much hail and snow.  We rode across the island to the neck of land
which joins the Rincon del Toro (the great peninsula at the S. W.
extremity) to the rest of the island.  From the great number of cows
which have been killed, there is a large proportion of bulls.  These
wander about single, or two and three together, and are very savage.  I
never saw such magnificent beasts; they equalled in the size of their
huge heads and necks the Grecian marble sculptures.  Capt. Sulivan
informs me that the hide of an average-sized bull weighs forty-seven
pounds, whereas a hide of this weight, less thoroughly dried, is
considered as a very heavy one at Monte Video.  The young bulls
generally run away, for a short distance; but the old ones do not stir
a step, except to rush at man and horse; and many horses have been thus
killed.  An old bull crossed a boggy stream, and took his stand on the
opposite side to us; we in vain tried to drive him away, and failing,
were obliged to make a large circuit.  The Gauchos in revenge
determined to emasculate him and render him for the future harmless. It
was very interesting to see how art completely mastered force.  One
lazo was thrown over his horns as he rushed at the horse, and another
round his hind legs: in a minute the monster was stretched powerless on
the ground. After the lazo has once been drawn tightly round the horns
of a furious animal, it does not at first appear an easy thing to
disengage it again without killing the beast: nor, I apprehend, would
it be so if the man was by himself.  By the aid, however, of a second
person throwing his lazo so as to catch both hind legs, it is quickly
managed: for the animal, as long as its hind legs are kept
outstretched, is quite helpless, and the first man can with his hands
loosen his lazo from the horns, and then quietly mount his horse; but
the moment the second man, by backing ever so little, relaxes the
strain, the lazo slips off the legs of the struggling beast, which then
rises free, shakes himself, and vainly rushes at his antagonist.

During our whole ride we saw only one troop of wild horses.  These
animals, as well as the cattle, were introduced by the French in 1764,
since which time both have greatly increased.  It is a curious fact,
that the horses have never left the eastern end of the island, although
there is no natural boundary to prevent them from roaming, and that
part of the island is not more tempting than the rest.  The Gauchos
whom I asked, though asserting this to be the case, were unable to
account for it, except from the strong attachment which horses have to
any locality to which they are accustomed.  Considering that the island
does not appear fully stocked, and that there are no beasts of prey, I
was particularly curious to know what has checked their originally
rapid increase.  That in a limited island some check would sooner or
later supervene, is inevitable; but why had the increase of the horse
been checked sooner than that of the cattle?  Capt. Sulivan has taken
much pains for me in this inquiry.  The Gauchos employed here attribute
it chiefly to the stallions constantly roaming from place to place, and
compelling the mares to accompany them, whether or not the young foals
are able to follow.  One Gaucho told Capt. Sulivan that he had watched
a stallion for a whole hour, violently kicking and biting a mare till
he forced her to leave her foal to its fate.  Capt. Sulivan can so far
corroborate this curious account, that he has several times found young
foals dead, whereas he has never found a dead calf.  Moreover, the dead
bodies of full-grown horses are more frequently found, as if more
subject to disease or accidents, than those of the cattle.  From the
softness of the ground their hoofs often grow irregularly to a great
length, and this causes lameness.  The predominant colours are roan and
iron-grey.  All the horses bred here, both tame and wild, are rather
small-sized, though generally in good condition; and they have lost so
much strength, that they are unfit to be used in taking wild cattle
with the lazo: in consequence, it is necessary to go to the great
expense of importing fresh horses from the Plata.  At some future
period the southern hemisphere probably will have its breed of Falkland
ponies, as the northern has its Shetland breed.

The cattle, instead of having degenerated like the horses seem, as
before remarked, to have increased in size; and they are much more
numerous than the horses. Capt. Sulivan informs me that they vary much
less in the general form of their bodies and in the shape of their
horns than English cattle.  In colour they differ much; and it is a
remarkable circumstance, that in different parts of this one small
island, different colours predominate.  Round Mount Usborne, at a
height of from 1000 to 1500 feet above the sea, about half of some of
the herds are mouse or lead-coloured, a tint which is not common in
other parts of the island. Near Port Pleasant dark brown prevails,
whereas south of Choiseul Sound (which almost divides the island into
two parts), white beasts with black heads and feet are the most common:
in all parts black, and some spotted animals may be observed.  Capt.
Sulivan remarks, that the difference in the prevailing colours was so
obvious, that in looking for the herds near Port Pleasant, they
appeared from a long distance like black spots, whilst south of
Choiseul Sound they appeared like white spots on the hill-sides.  Capt.
Sulivan thinks that the herds do not mingle; and it is a singular fact,
that the mouse-coloured cattle, though living on the high land, calve
about a month earlier in the season that the other coloured beasts on
the lower land.  It is interesting thus to find the once domesticated
cattle breaking into three colours, of which some one colour would in
all probability ultimately prevail over the others, if the herds were
left undisturbed for the next several centuries.

The rabbit is another animal which has been introduced; and has
succeeded very well; so that they abound over large parts of the
island.  Yet, like the horses, they are confined within certain limits;
for they have not crossed the central chain of hills, nor would they
have extended even so far as its base, if, as the Gauchos informed me,
small colonies has not been carried there.  I should not have supposed
that these animals, natives of northern Africa, could have existed in a
climate so humid as this, and which enjoys so little sunshine that even
wheat ripens only occasionally.  It is asserted that in Sweden, which
any one would have thought a more favourable climate, the rabbit cannot
live out of doors.  The first few pairs, moreover, had here to content
against pre-existing enemies, in the fox and some large hawks.  The
French naturalists have considered the black variety a distinct
species, and called it Lepus Magellanicus. [5] They imagined that
Magellan, when talking of an animal under the name of "conejos" in the
Strait of Magellan, referred to this species; but he was alluding to a
small cavy, which to this day is thus called by the Spaniards.  The
Gauchos laughed at the idea of the black kind being different from the
grey, and they said that at all events it had not extended its range
any further than the grey kind; that the two were never found separate;
and that they readily bred together, and produced piebald offspring. Of
the latter I now possess a specimen, and it is marked about the head
differently from the French specific description.  This circumstance
shows how cautious naturalists should be in making species; for even
Cuvier, on looking at the skull of one of these rabbits, thought it was
probably distinct!

The only quadruped native to the island [6]; is a large wolf-like fox
(Canis antarcticus), which is common to both East and West Falkland.  I
have no doubt it is a peculiar species, and confined to this
archipelago; because many sealers, Gauchos, and Indians, who have
visited these islands, all maintain that no such animal is found in any
part of South America.

Molina, from a similarity in habits, thought that this was the same
with his "culpeu;" [7] but I have seen both, and they are quite
distinct.  These wolves are well known from Byron's account of their
tameness and curiosity, which the sailors, who ran into the water to
avoid them, mistook for fierceness.  To this day their manners remain
the same. They have been observed to enter a tent, and actually pull
some meat from beneath the head of a sleeping seaman.  The Gauchos also
have frequently in the evening killed them, by holding out a piece of
meat in one hand, and in the other a knife ready to stick them.  As far
as I am aware, there is no other instance in any part of the world, of
so small a mass of broken land, distant from a continent, possessing so
large an aboriginal quadruped peculiar to itself.  Their numbers have
rapidly decreased; they are already banished from that half of the
island which lies to the eastward of the neck of land between St.
Salvador Bay and Berkeley Sound.  Within a very few years after these
islands shall have become regularly settled, in all probability this
for will be classed with the dodo, as an animal which has perished from
the face of the earth.

At night (17th) we slept on the neck of land at the head of Choiseul
Sound, which forms the south-west peninsula. The valley was pretty well
sheltered from the cold wind, but there was very little brushwood for
fuel.  The Gauchos, however, soon found what, to my great surprise,
made nearly as hot a fire as coals; this was the skeleton of a bullock
lately killed, from which the flesh had been picked by the
carrion-hawks.  They told me that in winter they often killed a beast,
cleaned the flesh from the bones with their knives, and then with these
same bones roasted the meat for their suppers.

18th.--It rained during nearly the whole day.  At night we managed,
however, with our saddle-cloths to keep ourselves pretty well dry and
warm; but the ground on which we slept was on each occasion nearly in
the state of a bog, and there was not a dry spot to sit down on after
our day's ride.  I have in another part stated how singular it is that
there should be absolutely no trees on these islands, although Tierra
del Fuego is covered by one large forest.  The largest bush in the
island (belonging to the family of Compositae) is scarcely so tall as
our gorse.  The best fuel is afforded by a green little bush about the
size of common heath, which has the useful property of burning while
fresh and green.  It was very surprising to see the Gauchos, in the
midst of rain and everything soaking wet, with nothing more than a
tinder-box and a piece of rag, immediately make a fire.  They sought
beneath the tufts of grass and bushel for a few dry twigs, and these
they rubbed into fibres; then surrounding them with coarser twigs,
something like a bird's nest, they put the rag with its spark of fire
in the middle and covered it up.  The nest being then held up to the
wind, by degrees it smoked more and more, and at last burst out in
flames.  I do not think any other method would have had a chance of
succeeding with such damp materials.

19th.--Each morning, from not having ridden for some time previously, I
was very stiff.  I was surprised to hear the Gauchos, who have from
infancy almost lived on horseback, say that, under similar
circumstances, they always suffer.  St. Jago told me, that having been
confined for three months by illness, he went out hunting wild cattle,
and in consequence, for the next two days, his thighs were so stiff
that he was obliged to lie in bed.  This shows that the Gauchos,
although they do not appear to do so, yet really must exert much
muscular effort in riding.  The hunting wild cattle, in a country so
difficult to pass as this is on account of the swampy ground, must be
very hard work.  The Gauchos say they often pass at full speed over
ground which would be impassable at a slower pace; in the same manner
as a man is able to skate over thin ice.  When hunting, the party
endeavours to get as close as possible to the herd without being
discovered.  Each man carries four or five pair of the bolas; these he
throws one after the other at as many cattle, which, when once
entangled, are left for some days till they become a little exhausted
by hunger and struggling. They are then let free and driven towards a
small herd of tame animals, which have been brought to the spot on
purpose. From their previous treatment, being too much terrified to
leave the herd, they are easily driven, if their strength last out, to
the settlement.

The weather continued so very bad that we determine to make a push, and
try to reach the vessel before night. From the quantity of rain which
had fallen, the surface of the whole country was swampy.  I suppose my
horse fell at least a dozen times, and sometimes the whole six horses
were floundering in the mud together.  All the little streams are
bordered by soft peat, which makes it very difficult for the horses to
leap them without falling.  To complete our discomforts we were obliged
to cross the head of a creek of the sea, in which the water was as high
as our horses' backs; and the little waves, owing to the violence of
the wind, broke over us, and made us very wet and cold.  Even the
iron-framed Gauchos professed themselves glad when they reached the
settlement, after our little excursion.

The geological structure of these islands is in most respects simple.
The lower country consists of clay-slate and sandstone, containing
fossils, very closely related to, but not identical with, those found
in the Silurian formations of Europe; the hills are formed of white
granular quartz rock.  The strata of the latter are frequently arched
with perfect symmetry, and the appearance of some of the masses is in
consequence most singular.  Pernety [8] has devoted several pages to
the description of a Hill of Ruins, the successive strata of which he
has justly compared to the seats of an amphitheatre.  The quartz rock
must have been quite pasty when it underwent such remarkable flexures
without being shattered into fragments.  As the quartz insensibly
passes into the sandstone, it seems probable that the former owes its
origin to the sandstone having been heated to such a degree that it
became viscid, and upon cooling crystallized.  While in the soft state
it must have been pushed up through the overlying beds.

In many parts of the island the bottoms of the valleys are covered in
an extraordinary manner by myriads of great loose angular fragments of
the quartz rock, forming "streams of stones." These have been mentioned
with surprise by every voyager since the time of Pernety.  The blocks
are not water-worn, their angles being only a little blunted; they vary
in size from one or two feet in diameter to ten, or even more than
twenty times as much.  They are not thrown together into irregular
piles, but are spread out into level sheets or great streams.  It is
not possible to ascertain their thickness, but the water of small
streamlets can be heard trickling through the stones many feet below
the surface. The actual depth is probably great, because the crevices
between the lower fragments must long ago have been filled up with
sand.  The width of these sheets of stones varied from a few hundred
feet to a mile; but the peaty soil daily encroaches on the borders, and
even forms islets wherever a few fragments happen to lie close
together.  In a valley south of Berkeley Sound, which some of our party
called the "great valley of fragments," it was necessary to cross an
uninterrupted band half a mile wide, by jumping from one pointed stone
to another.  So large were the fragments, that being overtaken by a
shower of rain, I readily found shelter beneath one of them.

Their little inclination is the most remarkable circumstance in these
"streams of stones." On the hill-sides I have seen them sloping at an
angle of ten degrees with the horizon; but in some of the level,
broad-bottomed valleys, the inclination is only just sufficient to be
clearly perceived. On so rugged a surface there was no means of
measuring the angle, but to give a common illustration, I may say that
the slope would not have checked the speed of an English mail-coach. In
some places, a continuous stream of these fragments followed up the
course of a valley, and even extended to the very crest of the hill. On
these crests huge masses, exceeding in dimensions any small building,
seemed to stand arrested in their headlong course: there, also, the
curved strata of the archways lay piled on each other, like the ruins
of some vast and ancient cathedral.  In endeavouring to describe these
scenes of violence one is tempted to pass from one simile to another.
We may imagine that streams of white lava had flowed from many parts of
the mountains into the lower country, and that when solidified they had
been rent by some enormous convulsion into myriads of fragments. The
expression "streams of stones," which immediately occurred to every
one, conveys the same idea.  These scenes are on the spot rendered more
striking by the contrast of the low rounded forms of the neighbouring
hills.

I was interested by finding on the highest peak of one range (about 700
feet above the sea) a great arched fragment, lying on its convex side,
or back downwards.  Must we believe that it was fairly pitched up in
the air, and thus turned?  Or, with more probability, that there
existed formerly a part of the same range more elevated than the point
on which this monument of a great convulsion of nature now lies.  As
the fragments in the valleys are neither rounded nor the crevices
filled up with sand, we must infer that the period of violence was
subsequent to the land having been raised above the waters of the sea.
In a transverse section within these valleys, the bottom is nearly
level, or rises but very little towards either side.  Hence the
fragments appear to have travelled from the head of the valley; but in
reality it seems more probable that they have been hurled down from the
nearest slopes; and that since, by a vibratory movement of overwhelming
force, [9] the fragments have been levelled into one continuous sheet.
If during the earthquake [10] which in 1835 overthrew Concepcion, in
Chile, it was thought wonderful that small bodies should have been
pitched a few inches from the ground, what must we say to a movement
which has caused fragments many tons in weight, to move onwards like so
much sand on a vibrating board, and find their level?  I have seen, in
the Cordillera of the Andes, the evident marks where stupendous
mountains have been broken into pieces like so much thin crust, and the
strata thrown of their vertical edges; but never did any scene, like
these "streams of stones," so forcibly convey to my mind the idea of a
convulsion, of which in historical records we might in vain seek for
any counterpart: yet the progress of knowledge will probably some day
give a simple explanation of this phenomenon, as it already has of the
so long-thought inexplicable transportal of the erratic boulders, which
are strewed over the plains of Europe.

I have little to remark on the zoology of these islands. have before
described the carrion-vulture of Polyborus. There are some other hawks,
owls, and a few small land-birds. The water-fowl are particularly
numerous, and they must formerly, from the accounts of the old
navigators, have been much more so.  One day I observed a cormorant
playing with a fish which it had caught.  Eight times successively the
bird let its prey go, then dived after it, and although in deep water,
brought it each time to the surface. In the Zoological Gardens I have
seen the otter treat a fish in the same manner, much as a cat does a
mouse: I do not know of any other instance where dame Nature appears so
wilfully cruel.  Another day, having placed myself between a penguin
(Aptenodytes demersa) and the water, I was much amused by watching its
habits.  It was a brave bird; and till reaching the sea, it regularly
fought and drove me backwards. Nothing less than heavy blows would have
stopped him; every inch he gained he firmly kept, standing close before
me erect and determined.  When thus opposed he continually rolled his
head from side to side, in a very odd manner, as if the power of
distinct vision lay only in the anterior and basal part of each eye.
This bird is commonly called the jackass penguin, from its habit, while
on shore, of throwing its head backwards, and making a loud strange
noise, very like the braying of an ass; but while at sea, and
undisturbed, its note is very deep and solemn, and is often heard in
the night-time. In diving, its little wings are used as fins; but on
the land, as front legs.  When crawling, it may be said on four legs,
through the tussocks or on the side of a grassy cliff, it moves so very
quickly that it might easily be mistaken for a quadruped.  When at sea
and fishing, it comes to the surface for the purpose of breathing with
such a spring, and dives again so instantaneously, that I defy any one
at first sight to be sure that it was not a fish leaping for sport.

Two kinds of geese frequent the Falklands.  The upland species (Anas
Magellanica) is common, in pairs and in small flocks, throughout the
island.  They do not migrate, but build on the small outlying islets.
This is supposed to be from fear of the foxes: and it is perhaps from
the same cause that these birds, though very tame by day, are shy and
wild in the dusk of the evening.  They live entirely on vegetable
matter.

The rock-goose, so called from living exclusively on the sea-beach
(Anas antarctica), is common both here and on the west coast of
America, as far north as Chile.  In the deep and retired channels of
Tierra del Fuego, the snow-white gander, invariably accompanied by his
darker consort, and standing close by each other on some distant rocky
point, is a common feature in the landscape.

In these islands a great loggerheaded duck or goose (Anas brachyptera),
which sometimes weighs twenty-two pounds, is very abundant.  These
birds were in former days called, from their extraordinary manner of
paddling and splashing upon the water, race-horses; but now they are
named, much more appropriately, steamers.  Their wings are too small
and weak to allow of flight, but by their aid, partly swimming and
partly flapping the surface of the water, they move very quickly.  The
manner is something like that by which the common house-duck escapes
when pursued by a dog; but I am nearly sure that the steamer moves its
wings alternately, instead of both together, as in other birds.  These
clumsy, loggerheaded ducks make such a noise and splashing, that the
effect is exceedingly curious.

Thus we find in South America three birds which use their wings for
other purposes besides flight; the penguins as fins, the steamer as
paddles, and the ostrich as sails: and the Apteryz of New Zealand, as
well as its gigantic extinct prototype the Deinornis, possess only
rudimentary representatives of wings.  The steamer is able to dive only
to a very short distance.  It feeds entirely on shell-fish from the
kelp and tidal rocks: hence the beak and head, for the purpose of
breaking them, are surprisingly heavy and strong: the head is so strong
that I have scarcely been able to fracture it with my geological
hammer; and all our sportsmen soon discovered how tenacious these birds
were of life.  When in the evening pluming themselves in a flock, they
make the same odd mixture of sounds which bull-frogs do within the
tropics.

In Tierra del Fuego, as well as in the Falkland Islands, made many
observations on the lower marine animals, [11] but they are of little
general interest.  I will mention only one class of facts, relating to
certain zoophytes in the more highly organized division of that class.
Several genera (Flustra, Eschara, Cellaria, Crisia, and others) agree
in having singular moveable organs (like those of Flustra avicularia,
found in the European seas) attached to their cells.  The organ, in the
greater number of cases, very closely resembles the head of a vulture;
but the lower mandible can be opened much wider than in a real bird's
beak.  The head itself possessed considerable powers of movement, by
means of a short neck. In one zoophyte the head itself was fixed, but
the lower jaw free: in another it was replaced by a triangular hood,
with beautifully-fitted trap-door, which evidently answered to the
lower mandible.  In the greater number of species, each cell was
provided with one head, but in others each cell had two.

The young cells at the end of the branches of these corallines contain
quite immature polypi, yet the vulture-head attached to them, though
small, are in every respect perfect When the polypus was removed by a
needle from any of the cells, these organs did not appear in the least
affected.  When one of the vulture-like heads was cut off from the
cell, the lower mandible retained its power of opening and closing.
Perhaps the most singular part of their structure is, that when there
were more than two rows of cells on a branch, the central cells were
furnished with these appendages, of only one-fourth the size of the
outside ones.  Their movements varied according to the species; but in
some I never saw the least motion; while others, with the lower
mandible generally wide open, oscillated backwards and forwards at the
rate of about five seconds each turn, others moved rapidly and by
starts.  When touched with a needle, the beak generally seized the
point so firmly, that the whole branch might be shaken.

These bodies have no relation whatever with the production of the eggs
or gemmules, as they are formed before the young polypi appear in the
cells at the end of the growing branches; as they move independently of
the polypi, and do not appear to be in any way connected with them; and
as they differ in size on the outer and inner rows of cells, I have
little doubt, that in their functions, they are related rather to the
horny axis of the branches than to the polypi in the cells.  The fleshy
appendage at the lower extremity of the sea-pen (described at Bahia
Blanca) also forms part of the zoophyte, as a whole, in the same manner
as the roots of a tree form part of the whole tree, and not of the
individual leaf or flower-buds.

In another elegant little coralline (Crisia?), each cell was furnished
with a long-toothed bristle, which had the power of moving quickly.
Each of these bristles and each of the vulture-like heads generally
moved quite independently of the others, but sometimes all on both
sides of a branch, sometimes only those on one side, moved together
coinstantaneously, sometimes each moved in regular order one after
another.  In these actions we apparently behold as perfect a
transmission of will in the zoophyte, though composed of thousands of
distinct polypi, as in any single animal.  The case, indeed, is not
different from that of the sea-pens, which, when touched, drew
themselves into the sand on the coast of Bahia Blanca.  I will state
one other instance of uniform action, though of a very different
nature, in a zoophyte closely allied to Clytia, and therefore very
simply organized. Having kept a large tuft of it in a basin of
salt-water, when it was dark I found that as often as I rubbed any part
of a branch, the whole became strongly phosphorescent with a green
light: I do not think I ever saw any object more beautifully so.  But
the remarkable circumstance was, that the flashes of light always
proceeded up the branches, from the base towards the extremities.

The examination of these compound animals was always very interesting
to me.  What can be more remarkable that to see a plant-like body
producing an egg, capable of swimming about and of choosing a proper
place to adhere to, which then sprouts into branches, each crowded with
innumerable distinct animals, often of complicated organizations. The
branches, moreover, as we have just seen, sometimes possess organs
capable of movement and independent of the polypi.  Surprising as this
union of separate individuals in common stock must always appear, every
tree displays the same fact, for buds must be considered as individual
plants. It is, however, natural to consider a polypus, furnished with a
mouth, intestines, and other organs, as a distinct individual, whereas
the individuality of a leaf-bud is not easily realised, so that the
union of separate individuals in a common body is more striking in a
coralline than in a tree.  Our conception of a compound animal, where
in some respects the individuality of each is not completed, may be
aided, by reflecting on the production of two distinct creatures by
bisecting a single one with a knife, or where Nature herself performs
the task of bisection.  We may consider the polypi in a zoophyte, or
the buds in a tree, as cases where the division of the individual has
not been completely effected.  Certainly in the case of trees, and
judging from analogy in that of corallines, the individuals propagated
by buds seem more intimately related to each other, than eggs or seeds
are to their parents.  It seems now pretty well established that plants
propagated by buds all partake of a common duration of life; and it is
familiar to every one, what singular and numerous peculiarities are
transmitted with certainty, by buds, layers, and grafts, which by
seminal propagation never or only casually reappear.

[1] The desserts of Syria are characterized, according to Volney (tom.
i. p. 351), by woody bushes, numerous rats, gazelles and hares.  In the
landscape of Patagonia, the guanaco replaces the gazelle, and the
agouti the hare.

[2] I noticed that several hours before any one of the condors died,
all the lice, with which it was infested, crawled to the outside
feathers.  I was assured that this always happens.

[3] London's Magazine of Nat. Hist., vol. vii.

[4] From accounts published since our voyage, and more especially from
several interesting letters from Capt. Sulivan, R. N., employed on the
survey, it appears that we took an exaggerated view of the badness of
the climate on these islands.  But when I reflect on the almost
universal covering of peat, and on the fact of wheat seldom ripening
here, I can hardly believe that the climate in summer is so fine and
dry as it has lately been represented.

[5] Lesson's Zoology of the Voyage of the Coquille, tom. i. p. 168. All
the early voyagers, and especially Bougainville, distinctly state that
the wolf-like fox was the only native animal on the island.  The
distinction of the rabbit as a species, is taken from peculiarities in
the fur, from the shape of the head, and from the shortness of the
ears.  I may here observe that the difference between the Irish and
English hare rests upon nearly similar characters, only more strongly
marked.

[6] I have reason, however, to suspect that there is a field-mouse. The
common European rat and mouse have roamed far from the habitations of
the settlers.  The common hog has also run wild on one islet; all are
of a black colour: the boars are very fierce, and have great trunks.

[7] The "culpeu" is the Canis Magellanicus brought home by Captain King
from the Strait of Magellan.  It is common in Chile.

[8] Pernety, Voyage aux Isles Malouines, p. 526.

[9] "Nous n'avons pas ete moins saisis d'etonnement a la vue de
l'innombrable quantite de pierres de touts grandeurs, bouleversees les
unes sur les autres, et cependent rangees, comme si elles avoient ete
amoncelees negligemment pour remplir des ravins.  On ne se lassoit pas
d'admirer les effets prodigieux de la nature."--Pernety, p. 526.

[10] An inhabitant of Mendoza, and hence well capable of judging,
assured me that, during the several years he had resided on these
islands, he had never felt the slightest shock of an earthquake.

[11] I was surprised to find, on counting the eggs of a large white
Doris (this sea-slug was three and a half inches long), how
extraordinarily numerous they were.  From two to five eggs (each
three-thousandths of an inch in diameter) were contained in spherical
little case.  These were arranged two deep in transverse rows forming a
ribbon.  The ribbon adhered by its edge to the rock in an oval spire.
One which I found, measured nearly twenty inches in length and half in
breadth.  By counting how many balls were contained in a tenth of an
inch in the row, and how many rows in an equal length of the ribbon, on
the most moderate computation there were six hundred thousand eggs. Yet
this Doris was certainly not very common; although I was often
searching under the stones, I saw only seven individuals.  No fallacy
is more common with naturalists, than that the numbers of an individual
species depend on its powers of propagation.



CHAPTER X

TIERRA DEL FUEGO

Tierra del Fuego, first arrival--Good Success Bay--An Account of the
Fuegians on board--Interview With the Savages--Scenery of the
Forests--Cape Horn--Wigwam Cove--Miserable Condition of the
Savages--Famines--Cannibals--Matricide--Religious Feelings--Great
Gale--Beagle Channel--Ponsonby Sound--Build Wigwams and settle the
Fuegians--Bifurcation of the Beagle Channel--Glaciers--Return to the
Ship--Second Visit in the Ship to the Settlement--Equality of Condition
amongst the Natives.


DECEMBER 17th, 1832.--Having now finished with Patagonia and the
Falkland Islands, I will describe our first arrival in Tierra del
Fuego.  A little after noon we doubled Cape St.  Diego, and entered the
famous strait of Le Maire.  We kept close to the Fuegian shore, but the
outline of the rugged, inhospitable Statenland was visible amidst the
clouds.  In the afternoon we anchored in the Bay of Good Success. While
entering we were saluted in a manner becoming the inhabitants of this
savage land.  A group of Fuegians partly concealed by the entangled
forest, were perched on a wild point overhanging the sea; and as we
passed by, they sprang up and waving their tattered cloaks sent forth a
loud and sonorous shout.  The savages followed the ship, and just
before dark we saw their fire, and again heard their wild cry. The
harbour consists of a fine piece of water half surrounded by low
rounded mountains of clay-slate, which are covered to the water's edge
by one dense gloomy forest.  A single glance at the landscape was
sufficient to show me how widely different it was from anything I had
ever beheld.  At night it blew a gale of wind, and heavy squalls from
the mountains swept past us.  It would have been a bad time out at sea,
and we, as well as others, may call this Good Success Bay.

In the morning the Captain sent a party to communicate with the
Fuegians.  When we came within hail, one of the four natives who were
present advanced to receive us, and began to shout most vehemently,
wishing to direct us where to land.  When we were on shore the party
looked rather alarmed, but continued talking and making gestures with
great rapidity.  It was without exception the most curious and
interesting spectacle I ever beheld: I could not have believed how wide
was the difference between savage and civilized man: it is greater than
between a wild and domesticated animal, inasmuch as in man there is a
greater power of improvement.  The chief spokesman was old, and
appeared to be the head of the family; the three others were powerful
young men, about six feet high.  The women and children had been sent
away.  These Fuegians are a very different race from the stunted,
miserable wretches farther westward; and they seem closely allied to
the famous Patagonians of the Strait of Magellan.  Their only garment
consists of a mantle made of guanaco skin, with the wool outside: this
they wear just thrown over their shoulders, leaving their persons as
often exposed as covered.  Their skin is of a dirty coppery-red colour.

The old man had a fillet of white feathers tied round his head, which
partly confined his black, coarse, and entangled hair.  His face was
crossed by two broad transverse bars; one, painted bright red, reached
from ear to ear and included the upper lip; the other, white like
chalk, extended above and parallel to the first, so that even his
eyelids were thus coloured.  The other two men were ornamented by
streaks of black powder, made of charcoal.  The party altogether
closely resembled the devils which come on the stage in plays like Der
Freischutz.

Their very attitudes were abject, and the expression of their
countenances distrustful, surprised, and startled.  After we had
presented them with some scarlet cloth, which they immediately tied
round their necks, they became good friends. This was shown by the old
man patting our breasts, and making a chuckling kind of noise, as
people do when feeding chickens.  I walked with the old man, and this
demonstration of friendship was repeated several times; it was
concluded by three hard slaps, which were given me on the breast and
back at the same time.  He then bared his bosom for me to return the
compliment, which being done, he seemed highly pleased.  The language
of these people, according to our notions, scarcely deserves to be
called articulate.  Captain Cook has compared it to a man clearing his
throat, but certainly no European ever cleared his throat with so many
hoarse, guttural, and clicking sounds.

They are excellent mimics: as often as we coughed or yawned, or made
any odd motion, they immediately imitated us.  Some of our party began
to squint and look awry; but one of the young Fuegians (whose whole
face was painted black, excepting a white band across his eyes)
succeeded in making far more hideous grimaces.  They could repeat with
perfect correctness each word in any sentence we addressed them, and
they remembered such words for some time.  Yet we Europeans all know
how difficult it is to distinguish apart the sounds in a foreign
language.  Which of us, for instance, could follow an American Indian
through a sentence of more than three words?  All savages appear to
possess, to an uncommon degree, this power of mimicry.  I was told,
almost in the same words, of the same ludicrous habit among the
Caffres; the Australians, likewise, have long been notorious for being
able to imitate and describe the gait of any man, so that he may be
recognized.  How can this faculty be explained? is it a consequence of
the more practised habits of perception and keener senses, common to
all men in a savage state, as compared with those long civilized?

When a song was struck up by our party, I thought the Fuegians would
have fallen down with astonishment.  With equal surprise they viewed
our dancing; but one of the young men, when asked, had no objection to
a little waltzing. Little accustomed to Europeans as they appeared to
be, yet they knew and dreaded our fire-arms; nothing would tempt them
to take a gun in their hands.  They begged for knives, calling them by
the Spanish word "cuchilla." They explained also what they wanted, by
acting as if they had a piece of blubber in their mouth, and then
pretending to cut instead of tear it.

I have not as yet noticed the Fuegians whom we had on board.  During
the former voyage of the Adventure and Beagle in 1826 to 1830, Captain
Fitz Roy seized on a party of natives, as hostages for the loss of a
boat, which had been stolen, to the great jeopardy of a party employed
on the survey; and some of these natives, as well as a child whom he
bought for a pearl-button, he took with him to England, determining to
educate them and instruct them in religion at his own expense.  To
settle these natives in their own country, was one chief inducement to
Captain Fitz Roy to undertake our present voyage; and before the
Admiralty had resolved to send out this expedition, Captain Fitz Roy
had generously chartered a vessel, and would himself have taken them
back.  The natives were accompanied by a missionary, R. Matthews; of
whom and of the natives, Captain Fitz Roy has published a full and
excellent account.  Two men, one of whom died in England of the
small-pox, a boy and a little girl, were originally taken; and we had
now on board, York Minster, Jemmy Button (whose name expresses his
purchase-money), and Fuegia Basket.  York Minster was a full-grown,
short, thick, powerful man: his disposition was reserved, taciturn,
morose, and when excited violently passionate; his affections were very
strong towards a few friends on board; his intellect good.  Jemmy
Button was a universal favourite, but likewise passionate; the
expression of his face at once showed his nice disposition.  He was
merry and often laughed, and was remarkably sympathetic with any one in
pain: when the water was rough, I was often a little sea-sick, and he
used to come to me and say in a plaintive voice, "Poor, poor fellow!"
but the notion, after his aquatic life, of a man being sea-sick, was
too ludicrous, and he was generally obliged to turn on one side to hide
a smile or laugh, and then he would repeat his "Poor, poor fellow!" He
was of a patriotic disposition; and he liked to praise his own tribe
and country, in which he truly said there were "plenty of trees," and
he abused all the other tribes: he stoutly declared that there was no
Devil in his land. Jemmy was short, thick, and fat, but vain of his
personal appearance; he used always to wear gloves, his hair was neatly
cut, and he was distressed if his well-polished shoes were dirtied.  He
was fond of admiring himself in a looking glass; and a merry-faced
little Indian boy from the Rio Negro, whom we had for some months on
board, soon perceived this, and used to mock him: Jemmy, who was always
rather jealous of the attention paid to this little boy, did not at all
like this, and used to say, with rather a contemptuous twist of his
head, "Too much skylark." It seems yet wonderful to me, when I think
over all his many good qualities that he should have been of the same
race, and doubtless partaken of the same character, with the miserable,
degraded savages whom we first met here.  Lastly, Fuegia Basket was a
nice, modest, reserved young girl, with a rather pleasing but sometimes
sullen expression, and very quick in learning anything, especially
languages.  This she showed in picking up some Portuguese and Spanish,
when left on shore for only a short time at Rio de Janeiro and Monte
Video, and in her knowledge of English.  York Minster was very jealous
of any attention paid to her; for it was clear he determined to marry
her as soon as they were settled on shore.

Although all three could both speak and understand a good deal of
English, it was singularly difficult to obtain much information from
them, concerning the habits of their countrymen; this was partly owing
to their apparent difficulty in understanding the simplest alternative.
Every one accustomed to very young children, knows how seldom one can
get an answer even to so simple a question as whether a thing is black
or white; the idea of black or white seems alternately to fill their
minds.  So it was with these Fuegians, and hence it was generally
impossible to find out, by cross questioning, whether one had rightly
understood anything which they had asserted.  Their sight was
remarkably acute; it is well known that sailors, from long practice,
can make out a distant object much better than a landsman; but both
York and Jemmy were much superior to any sailor on board: several times
they have declared what some distant object has been, and though
doubted by every one, they have proved right, when it has been examined
through a telescope.  They were quite conscious of this power; and
Jemmy, when he had any little quarrel with the officer on watch, would
say, "Me see ship, me no tell."

It was interesting to watch the conduct of the savages, when we landed,
towards Jemmy Button: they immediately perceived the difference between
him and ourselves, and held much conversation one with another on the
subject.  The old man addressed a long harangue to Jemmy, which it
seems was to invite him to stay with them. But Jemmy understood very
little of their language, and was, moreover, thoroughly ashamed of his
countrymen.  When York Minster afterwards came on shore, they noticed
him in the same way, and told him he ought to shave; yet he had not
twenty dwarf hairs on his face, whilst we all wore our untrimmed
beards.  They examined the colour of his skin, and compared it with
ours.  One of our arms being bared, they expressed the liveliest
surprise and admiration at its whiteness, just in the same way in which
I have seen the ourangoutang do at the Zoological Gardens.  We thought
that they mistook two or three of the officers, who were rather shorter
and fairer, though adorned with large beards, for the ladies of our
party.  The tallest amongst the Fuegians was evidently much pleased at
his height being noticed.  When placed back to back with the tallest of
the boat's crew, he tried his best to edge on higher ground, and to
stand on tiptoe.  He opened his mouth to show his teeth, and turned his
face for a side view; and all this was done with such alacrity, that I
dare say he thought himself the handsomest man in Tierra del Fuego.
After our first feeling of grave astonishment was over, nothing could
be more ludicrous than the odd mixture of surprise and imitation which
these savages every moment exhibited.


The next day I attempted to penetrate some way into the country. Tierra
del Fuego may be described as a mountainous land, partly submerged in
the sea, so that deep inlets and bays occupy the place where valleys
should exist.  The mountain sides, except on the exposed western coast,
are covered from the water's edge upwards by one great forest. The
trees reach to an elevation of between 1000 and 1500 feet, and are
succeeded by a band of peat, with minute alpine plants; and this again
is succeeded by the line of perpetual snow, which, according to Captain
King, in the Strait of Magellan descends to between 3000 and 4000 feet.
To find an acre of level land in any part of the country is most rare.
I recollect only one little flat piece near Port Famine, and another of
rather larger extent near Goeree Road.  In both places, and everywhere
else, the surface is covered by a thick bed of swampy peat. Even within
the forest, the ground is concealed by a mass of slowly putrefying
vegetable matter, which, from being soaked with water, yields to the
foot.

Finding it nearly hopeless to push my way through the wood, I followed
the course of a mountain torrent.  At first, from the waterfalls and
number of dead trees, I could hardly crawl along; but the bed of the
stream soon became a little more open, from the floods having swept the
sides.  I continued slowly to advance for an hour along the broken and
rocky banks, and was amply repaid by the grandeur of the scene.  The
gloomy depth of the ravine well accorded with the universal signs of
violence.  On every side were lying irregular masses of rock and
torn-up trees; other trees, though still erect, were decayed to the
heart and ready to fall.  The entangled mass of the thriving and the
fallen reminded me of the forests within the tropics--yet there was a
difference: for in these still solitudes, Death, instead of Life,
seemed the predominant spirit.  I followed the water-course till I came
to a spot where a great slip had cleared a straight space down the
mountain side.  By this road I ascended to a considerable elevation,
and obtained a good view of the surrounding woods.  The trees all
belong to one kind, the Fagus betuloides; for the number of the other
species of Fagus and of the Winter's Bark, is quite inconsiderable.
This beech keeps its leaves throughout the year; but its foliage is of
a peculiar brownish-green colour, with a tinge of yellow.  As the whole
landscape is thus coloured, it has a sombre, dull appearance; nor is it
often enlivened by the rays of the sun.

December 20th.--One side of the harbour is formed by a hill about 1500
feet high, which Captain Fitz Roy has called after Sir J. Banks, in
commemoration of his disastrous excursion, which proved fatal to two
men of his party, and nearly so to Dr. Solander.  The snow-storm, which
was the cause of their misfortune, happened in the middle of January,
corresponding to our July, and in the latitude of Durham! I was anxious
to reach the summit of this mountain to collect alpine plants; for
flowers of any kind in the lower parts are few in number.  We followed
the same water-course as on the previous day, till it dwindled away,
and we were then compelled to crawl blindly among the trees. These,
from the effects of the elevation and of the impetuous winds, were low,
thick and crooked.  At length we reached that which from a distance
appeared like a carpet of fine green turf, but which, to our vexation,
turned out to be a compact mass of little beech-trees about four or
five feet high.  They were as thick together as box in the border of a
garden, and we were obliged to struggle over the flat but treacherous
surface.  After a little more trouble we gained the peat, and then the
bare slate rock.

A ridge connected this hill with another, distant some miles, and more
lofty, so that patches of snow were lying on it.  As the day was not
far advanced, I determined to walk there and collect plants along the
road.  It would have been very hard work, had it not been for a
well-beaten and straight path made by the guanacos; for these animals,
like sheep, always follow the same line.  When we reached the hill we
found it the highest in the immediate neighbourhood, and the waters
flowed to the sea in opposite directions.  We obtained a wide view over
the surrounding country: to the north a swampy moorland extended, but
to the south we had a scene of savage magnificence, well becoming
Tierra del Fuego.  There was a degree of mysterious grandeur in
mountain behind mountain, with the deep intervening valleys, all
covered by one thick, dusky mass of forest.  The atmosphere, likewise,
in this climate, where gale succeeds gale, with rain, hail, and sleet,
seems blacker than anywhere else.  In the Strait of Magellan looking
due southward from Port Famine, the distant channels between the
mountains appeared from their gloominess to lead beyond the confines of
this world.

December 21st.--The Beagle got under way: and on the succeeding day,
favoured to an uncommon degree by a fine easterly breeze, we closed in
with the Barnevelts, and running past Cape Deceit with its stony peaks,
about three o'clock doubled the weather-beaten Cape Horn.  The evening
was calm and bright, and we enjoyed a fine view of the surrounding
isles.  Cape Horn, however, demanded his tribute, and before night sent
us a gale of wind directly in our teeth. We stood out to sea, and on
the second day again made the land, when we saw on our weather-bow this
notorious promontory in its proper form--veiled in a mist, and its dim
outline surrounded by a storm of wind and water.  Great black clouds
were rolling across the heavens, and squalls of rain, with hail, swept
by us with such extreme violence, that the Captain determined to run
into Wigwam Cove. This is a snug little harbour, not far from Cape
Horn; and here, at Christmas-eve, we anchored in smooth water.  The
only thing which reminded us of the gale outside, was every now and
then a puff from the mountains, which made the ship surge at her
anchors.

December 25th.--Close by the Cove, a pointed hill, called Kater's Peak,
rises to the height of 1700 feet.  The surrounding islands all consist
of conical masses of greenstone, associated sometimes with less regular
hills of baked and altered clay-slate.  This part of Tierra del Fuego
may be considered as the extremity of the submerged chain of mountains
already alluded to.  The cove takes its name of "Wigwam" from some of
the Fuegian habitations; but every bay in the neighbourhood might be so
called with equal propriety.  The inhabitants, living chiefly upon
shell-fish, are obliged constantly to change their place of residence;
but they return at intervals to the same spots, as is evident from the
piles of old shells, which must often amount to many tons in freight.
These heaps can be distinguished at a long distance by the bright green
colour of certain plants, which invariably grow on them.  Among these
may be enumerated the wild celery and scurvy grass, two very
serviceable plants, the use of which has not been discovered by the
natives.

The Fuegian wigwam resembles, in size and dimensions, a haycock.  It
merely consists of a few broken branches stuck in the ground, and very
imperfectly thatched on one side with a few tufts of grass and rushes.
The whole cannot be the work of an hour, and it is only used for a few
days. At Goeree Roads I saw a place where one of these naked men had
slept, which absolutely offered no more cover than the form of a hare.
The man was evidently living by himself, and York Minster said he was
"very bad man," and that probably he had stolen something.  On the west
coast, however, the wigwams are rather better, for they are covered
with seal-skins.  We were detained here several days by the bad
weather.  The climate is certainly wretched: the summer solstice was
now passed, yet every day snow fell on the hills, and in the valleys
there was rain, accompanied by sleet.  The thermometer generally stood
about 45 degs., but in the night fell to 38 or 40 degs.  From the damp
and boisterous state of the atmosphere, not cheered by a gleam of
sunshine, one fancied the climate even worse than it really was.

While going one day on shore near Wollaston Island, we pulled alongside
a canoe with six Fuegians.  These were the most abject and miserable
creatures I anywhere beheld.  On the east coast the natives, as we have
seen, have guanaco cloaks, and on the west they possess seal-skins.
Amongst these central tribes the men generally have an otter-skin, or
some small scrap about as large as a pocket-handkerchief, which is
barely sufficient to cover their backs as low down as their loins.  It
is laced across the breast by strings, and according as the wind blows,
it is shifted from side to side. But these Fuegians in the canoe were
quite naked, and even one full-grown woman was absolutely so.  It was
raining heavily, and the fresh water, together with the spray, trickled
down her body.  In another harbour not far distant, a woman, who was
suckling a recently-born child, came one day alongside the vessel, and
remained there out of mere curiosity, whilst the sleet fell and thawed
on her naked bosom, and on the skin of her naked baby!  These poor
wretches were stunted in their growth, their hideous faces bedaubed
with white paint, their skins filthy and greasy, their hair entangled,
their voices discordant, and their gestures violent.  Viewing such men,
one can hardly make one's self believe that they are fellow-creatures,
and inhabitants of the same world.  It is a common subject of
conjecture what pleasure in life some of the lower animals can enjoy:
how much more reasonably the same question may be asked with respect to
these barbarians!  At night, five or six human beings, naked and
scarcely protected from the wind and rain of this tempestuous climate,
sleep on the wet ground coiled up like animals.  Whenever it is low
water, winter or summer, night or day, they must rise to pick
shell-fish from the rocks; and the women either dive to collect
sea-eggs, or sit patiently in their canoes, and with a baited hair-line
without any hook, jerk out little fish.  If a seal is killed, or the
floating carcass of a putrid whale is discovered, it is a feast; and
such miserable food is assisted by a few tasteless berries and fungi.

They often suffer from famine: I heard Mr. Low, a sealing-master
intimately acquainted with the natives of this country, give a curious
account of the state of a party of one hundred and fifty natives on the
west coast, who were very thin and in great distress.  A succession of
gales prevented the women from getting shell-fish on the rocks, and
they could not go out in their canoes to catch seal.  A small party of
these men one morning set out, and the other Indians explained to him,
that they were going a four days' journey for food: on their return,
Low went to meet them, and he found them excessively tired, each man
carrying a great square piece of putrid whale's-blubber with a hole in
the middle, through which they put their heads, like the Gauchos do
through their ponchos or cloaks.  As soon as the blubber was brought
into a wigwam, an old man cut off thin slices, and muttering over them,
broiled them for a minute, and distributed them to the famished party,
who during this time preserved a profound silence.  Mr. Low believes
that whenever a whale is cast on shore, the natives bury large pieces
of it in the sand, as a resource in time of famine; and a native boy,
whom he had on board, once found a stock thus buried.  The different
tribes when at war are cannibals.  From the concurrent, but quite
independent evidence of the boy taken by Mr. Low, and of Jemmy Button,
it is certainly true, that when pressed in winter by hunger, they kill
and devour their old women before they kill their dogs: the boy, being
asked by Mr. Low why they did this, answered, "Doggies catch otters,
old women no." This boy described the manner in which they are killed
by being held over smoke and thus choked; he imitated their screams as
a joke, and described the parts of their bodies which are considered
best to eat.  Horrid as such a death by the hands of their friends and
relatives must be, the fears of the old women, when hunger begins to
press, are more painful to think of; we are told that they then often
run away into the mountains, but that they are pursued by the men and
brought back to the slaughter-house at their own firesides!

Captain Fitz Roy could never ascertain that the Fuegians have any
distinct belief in a future life.  They sometimes bury their dead in
caves, and sometimes in the mountain forests; we do not know what
ceremonies they perform. Jemmy Button would not eat land-birds, because
"eat dead men": they are unwilling even to mention their dead friends.
We have no reason to believe that they perform any sort of religious
worship; though perhaps the muttering of the old man before he
distributed the putrid blubber to his famished party, may be of this
nature.  Each family or tribe has a wizard or conjuring doctor, whose
office we could never clearly ascertain.  Jemmy believed in dreams,
though not, as I have said, in the devil: I do not think that our
Fuegians were much more superstitious than some of the sailors; for an
old quartermaster firmly believed that the successive heavy gales,
which we encountered off Cape Horn, were caused by our having the
Fuegians on board.  The nearest approach to a religious feeling which I
heard of, was shown by York Minster, who, when Mr. Bynoe shot some very
young ducklings as specimens, declared in the most solemn manner, "Oh,
Mr. Bynoe, much rain, snow, blow much." This was evidently a
retributive punishment for wasting human food.  In a wild and excited
manner he also related, that his brother, one day whilst returning to
pick up some dead birds which he had left on the coast, observed some
feathers blown by the wind.  His brother said (York imitating his
manner), "What that?" and crawling onwards, he peeped over the cliff,
and saw "wild man" picking his birds; he crawled a little nearer, and
then hurled down a great stone and killed him.  York declared for a
long time afterwards storms raged, and much rain and snow fell. As far
as we could make out, he seemed to consider the elements themselves as
the avenging agents: it is evident in this case, how naturally, in a
race a little more advanced in culture, the elements would become
personified.  What the "bad wild men" were, has always appeared to me
most mysterious: from what York said, when we found the place like the
form of a hare, where a single man had slept the night before, I should
have thought that they were thieves who had been driven from their
tribes; but other obscure speeches made me doubt this; I have sometimes
imagined that the most probable explanation was that they were insane.

The different tribes have no government or chief; yet each is
surrounded by other hostile tribes, speaking different dialects, and
separated from each other only by a deserted border or neutral
territory: the cause of their warfare appears to be the means of
subsistence.  Their country is a broken mass of wild rocks, lofty
hills, and useless forests: and these are viewed through mists and
endless storms.  The habitable land is reduced to the stones on the
beach; in search of food they are compelled unceasingly to wander from
spot to spot, and so steep is the coast, that they can only move about
in their wretched canoes.  They cannot know the feeling of having a
home, and still less that of domestic affection; for the husband is to
the wife a brutal master to a laborious slave.  Was a more horrid deed
ever perpetrated, than that witnessed on the west coast by Byron, who
saw a wretched mother pick up her bleeding dying infant-boy, whom her
husband had mercilessly dashed on the stones for dropping a basket of
sea-eggs!  How little can the higher powers of the mind be brought into
play: what is there for imagination to picture, for reason to compare,
or judgment to decide upon? to knock a limpet from the rock does not
require even cunning, that lowest power of the mind.  Their skill in
some respects may be compared to the instinct of animals; for it is not
improved by experience: the canoe, their most ingenious work, poor as
it is, has remained the same, as we know from Drake, for the last two
hundred and fifty years.

Whilst beholding these savages, one asks, whence have they come?  What
could have tempted, or what change compelled a tribe of men, to leave
the fine regions of the north, to travel down the Cordillera or
backbone of America, to invent and build canoes, which are not used by
the tribes of Chile, Peru, and Brazil, and then to enter on one of the
most inhospitable countries within the limits of the globe? Although
such reflections must at first seize on the mind, yet we may feel sure
that they are partly erroneous.  There is no reason to believe that the
Fuegians decrease in number; therefore we must suppose that they enjoy
a sufficient share of happiness, of whatever kind it may be, to render
life worth having.  Nature by making habit omnipotent, and its effects
hereditary, has fitted the Fuegian to the climate and the productions
of his miserable country.


After having been detained six days in Wigwam Cove by very bad weather,
we put to sea on the 30th of December. Captain Fitz Roy wished to get
westward to land York and Fuegia in their own country.  When at sea we
had a constant succession of gales, and the current was against us: we
drifted to 57 degs. 23' south.  On the 11th of January, 1833, by
carrying a press of sail, we fetched within a few miles of the great
rugged mountain of York Minster (so called by Captain Cook, and the
origin of the name of the elder Fuegian), when a violent squall
compelled us to shorten sail and stand out to sea.  The surf was
breaking fearfully on the coast, and the spray was carried over a cliff
estimated to 200 feet in height.  On the 12th the gale was very heavy,
and we did not know exactly where we were: it was a most unpleasant
sound to hear constantly repeated, "keep a good look-out to leeward."
On the 13th the storm raged with its full fury: our horizon was
narrowly limited by the sheets of spray borne by the wind.  The sea
looked ominous, like a dreary waving plain with patches of drifted
snow: whilst the ship laboured heavily, the albatross glided with its
expanded wings right up the wind.  At noon a great sea broke over us,
and filled one of the whale boats, which was obliged to be instantly
cut away.  The poor Beagle trembled at the shock, and for a few minutes
would not obey her helm; but soon, like a good ship that she was, she
righted and came up to the wind again.  Had another sea followed the
first, our fate would have been decided soon, and for ever.  We had now
been twenty-four days trying in vain to get westward; the men were worn
out with fatigue, and they had not had for many nights or days a dry
thing to put on.  Captain Fitz Roy gave up the attempt to get westward
by the outside coast.  In the evening we ran in behind False Cape Horn,
and dropped our anchor in forty-seven fathoms, fire flashing from the
windlass as the chain rushed round it.  How delightful was that still
night, after having been so long involved in the din of the warring
elements!

January 15th, 1833.--The Beagle anchored in Goeree Roads.  Captain Fitz
Roy having resolved to settle the Fuegians, according to their wishes,
in Ponsonby Sound, four boats were equipped to carry them there through
the Beagle Channel.  This channel, which was discovered by Captain Fitz
Roy during the last voyage, is a most remarkable feature in the
geography of this, or indeed of any other country: it may be compared
to the valley of Lochness in Scotland, with its chain of lakes and
friths.  It is about one hundred and twenty miles long, with an average
breadth, not subject to any very great variation, of about two miles;
and is throughout the greater part so perfectly straight, that the
view, bounded on each side by a line of mountains, gradually becomes
indistinct in the long distance.  It crosses the southern part of
Tierra del Fuego in an east and west line, and in the middle is joined
at right angles on the south side by an irregular channel, which has
been called Ponsonby Sound. This is the residence of Jemmy Button's
tribe and family.

19th.--Three whale-boats and the yawl, with a party of twenty-eight,
started under the command of Captain Fitz Roy.  In the afternoon we
entered the eastern mouth of the channel, and shortly afterwards found
a snug little cove concealed by some surrounding islets.  Here we
pitched our tents and lighted our fires.  Nothing could look more
comfortable than this scene.  The glassy water of the little harbour,
with the branches of the trees hanging over the rocky beach, the boats
at anchor, the tents supported by the crossed oars, and the smoke
curling up the wooded valley, formed a picture of quiet retirement. The
next day (20th) we smoothly glided onwards in our little fleet, and
came to a more inhabited district.  Few if any of these natives could
ever have seen a white man; certainly nothing could exceed their
astonishment at the apparition of the four boats.  Fires were lighted
on every point (hence the name of Tierra del Fuego, or the land of
fire), both to attract our attention and to spread far and wide the
news.  Some of the men ran for miles along the shore.  I shall never
forget how wild and savage one group appeared: suddenly four or five
men came to the edge of an overhanging cliff; they were absolutely
naked, and their long hair streamed about their faces; they held rugged
staffs in their hands, and, springing from the ground, they waved their
arms round their heads, and sent forth the most hideous yells.

At dinner-time we landed among a party of Fuegians. At first they were
not inclined to be friendly; for until the Captain pulled in ahead of
the other boats, they kept their slings in their hands.  We soon,
however, delighted them by trifling presents, such as tying red tape
round their heads. They liked our biscuit: but one of the savages
touched with his finger some of the meat preserved in tin cases which I
was eating, and feeling it soft and cold, showed as much disgust at it,
as I should have done at putrid blubber.  Jemmy was thoroughly ashamed
of his countrymen, and declared his own tribe were quite different, in
which he was wofully mistaken.  It was as easy to please as it was
difficult to satisfy these savages.  Young and old, men and children,
never ceased repeating the word "yammerschooner," which means "give
me." After pointing to almost every object, one after the other, even
to the buttons on our coats, and saying their favourite word in as many
intonations as possible, they would then use it in a neuter sense, and
vacantly repeat "yammerschooner." After yammerschoonering for any
article very eagerly, they would by a simple artifice point to their
young women or little children, as much as to say, "If you will not
give it me, surely you will to such as these."

At night we endeavoured in vain to find an uninhabited cove; and at
last were obliged to bivouac not far from a party of natives.  They
were very inoffensive as long as they were few in numbers, but in the
morning (21st) being joined by others they showed symptoms of
hostility, and we thought that we should have come to a skirmish.  An
European labours under great disadvantages when treating with savages
like these, who have not the least idea of the power of fire-arms.  In
the very act of levelling his musket he appears to the savage far
inferior to a man armed with a bow and arrow, a spear, or even a sling.
Nor is it easy to teach them our superiority except by striking a fatal
blow.  Like wild beasts, they do not appear to compare numbers; for
each individual, if attacked, instead of retiring, will endeavour to
dash your brains out with a stone, as certainly as a tiger under
similar circumstances would tear you.  Captain Fitz Roy on one occasion
being very anxious, from good reasons, to frighten away a small party,
first flourished a cutlass near them, at which they only laughed; he
then twice fired his pistol close to a native.  The man both times
looked astounded, and carefully but quickly rubbed his head; he then
stared awhile, and gabbled to his companions, but he never seemed to
think of running away.  We can hardly put ourselves in the position of
these savages, and understand their actions.  In the case of this
Fuegian, the possibility of such a sound as the report of a gun close
to his ear could never have entered his mind.  He perhaps literally did
not for a second know whether it was a sound or a blow, and therefore
very naturally rubbed his head.  In a similar manner, when a savage
sees a mark struck by a bullet, it may be some time before he is able
at all to understand how it is effected; for the fact of a body being
invisible from its velocity would perhaps be to him an idea totally
inconceivable.  Moreover, the extreme force of a bullet, that
penetrates a hard substance without tearing it, may convince the savage
that it has no force at all.  Certainly I believe that many savages of
the lowest grade, such as these of Tierra del Fuego, have seen objects
struck, and even small animals killed by the musket, without being in
the least aware how deadly an instrument it is.

22nd.--After having passed an unmolested night, in what would appear to
be neutral territory between Jemmy's tribe and the people whom we saw
yesterday, we sailed pleasantly along.  I do not know anything which
shows more clearly the hostile state of the different tribes, than
these wide border or neutral tracts.  Although Jemmy Button well knew
the force of our party, he was, at first, unwilling to land amidst the
hostile tribe nearest to his own.  He often told us how the savage Oens
men "when the leaf red," crossed the mountains from the eastern coast
of Tierra del Fuego, and made inroads on the natives of this part of
the country.  It was most curious to watch him when thus talking, and
see his eyes gleaming and his whole face assume a new and wild
expression.  As we proceeded along the Beagle Channel, the scenery
assumed a peculiar and very magnificent character; but the effect was
much lessened from the lowness of the point of view in a boat, and from
looking along the valley, and thus losing all the beauty of a
succession of ridges.  The mountains were here about three thousand
feet high, and terminated in sharp and jagged points.  They rose in one
unbroken sweep from the water's edge, and were covered to the height of
fourteen or fifteen hundred feet by the dusky-coloured forest.  It was
most curious to observe, as far as the eye could range, how level and
truly horizontal the line on the mountain side was, at which trees
ceased to grow: it precisely resembled the high-water mark of
drift-weed on a sea-beach.

At night we slept close to the junction of Ponsonby Sound with the
Beagle Channel.  A small family of Fuegians, who were living in the
cove, were quiet and inoffensive, and soon joined our party round a
blazing fire.  We were well clothed, and though sitting close to the
fire were far from too warm; yet these naked savages, though further
off, were observed, to our great surprise, to be streaming with
perspiration at undergoing such a roasting.  They seemed, however, very
well pleased, and all joined in the chorus of the seamen's songs: but
the manner in which they were invariably a little behindhand was quite
ludicrous.

During the night the news had spread, and early in the morning (23rd) a
fresh party arrived, belonging to the Tekenika, or Jemmy's tribe.
Several of them had run so fast that their noses were bleeding, and
their mouths frothed from the rapidity with which they talked; and with
their naked bodies all bedaubed with black, white, [1] and red, they
looked like so many demoniacs who had been fighting.  We then proceeded
(accompanied by twelve canoes, each holding four or five people) down
Ponsonby Sound to the spot where poor Jemmy expected to find his mother
and relatives.  He had already heard that his father was dead; but as
he had had a "dream in his head" to that effect, he did not seem to
care much about it, and repeatedly comforted himself with the very
natural reflection--"Me no help it." He was not able to learn any
particulars regarding his father's death, as his relations would not
speak about it.

Jemmy was now in a district well known to him, and guided the boats to
a quiet pretty cove named Woollya, surrounded by islets, every one of
which and every point had its proper native name.  We found here a
family of Jemmy's tribe, but not his relations: we made friends with
them; and in the evening they sent a canoe to inform Jemmy's mother and
brothers.  The cove was bordered by some acres of good sloping land,
not covered (as elsewhere) either by peat or by forest-trees.  Captain
Fitz Roy originally intended, as before stated, to have taken York
Minster and Fuegia to their own tribe on the west coast; but as they
expressed a wish to remain here, and as the spot was singularly
favourable, Captain Fitz Roy determined to settle here the whole party,
including Matthews, the missionary.  Five days were spent in building
for them three large wigwams, in landing their goods, in digging two
gardens, and sowing seeds.

The next morning after our arrival (the 24th) the Fuegians began to
pour in, and Jemmy's mother and brothers arrived.  Jemmy recognised the
stentorian voice of one of his brothers at a prodigious distance.  The
meeting was less interesting than that between a horse, turned out into
a field, when he joins an old companion.  There was no demonstration of
affection; they simply stared for a short time at each other; and the
mother immediately went to look after her canoe.  We heard, however,
through York that the mother has been inconsolable for the loss of
Jemmy and had searched everywhere for him, thinking that he might have
been left after having been taken in the boat.  The women took much
notice of and were very kind to Fuegia.  We had already perceived that
Jemmy had almost forgotten his own language.  I should think there was
scarcely another human being with so small a stock of language, for his
English was very imperfect.  It was laughable, but almost pitiable, to
hear him speak to his wild brother in English, and then ask him in
Spanish ("no sabe?") whether he did not understand him.

Everything went on peaceably during the three next days whilst the
gardens were digging and wigwams building.  We estimated the number of
natives at about one hundred and twenty.  The women worked hard, whilst
the men lounged about all day long, watching us.  They asked for
everything they saw, and stole what they could.  They were delighted at
our dancing and singing, and were particularly interested at seeing us
wash in a neighbouring brook; they did not pay much attention to
anything else, not even to our boats.  Of all the things which York
saw, during his absence from his country, nothing seems more to have
astonished him than an ostrich, near Maldonado: breathless with
astonishment he came running to Mr. Bynoe, with whom he was out
walking--"Oh, Mr. Bynoe, oh, bird all same horse!" Much as our white
skins surprised the natives, by Mr. Low's account a negro-cook to a
sealing vessel, did so more effectually, and the poor fellow was so
mobbed and shouted at that he would never go on shore again.
Everything went on so quietly that some of the officers and myself took
long walks in the surrounding hills and woods.  Suddenly, however, on
the 27th, every woman and child disappeared.  We were all uneasy at
this, as neither York nor Jemmy could make out the cause.  It was
thought by some that they had been frightened by our cleaning and
firing off our muskets on the previous evening; by others, that it was
owing to offence taken by an old savage, who, when told to keep further
off, had coolly spit in the sentry's face, and had then, by gestures
acted over a sleeping Fuegian, plainly showed, as it was said, that he
should like to cut up and eat our man.  Captain Fitz Roy, to avoid the
chance of an encounter, which would have been fatal to so many of the
Fuegians, thought it advisable for us to sleep at a cove a few miles
distant. Matthews, with his usual quiet fortitude (remarkable in a man
apparently possessing little energy of character), determined to stay
with the Fuegians, who evinced no alarm for themselves; and so we left
them to pass their first awful night.

On our return in the morning (28th) we were delighted to find all
quiet, and the men employed in their canoes spearing fish.  Captain
Fitz Roy determined to send the yawl and one whale-boat back to the
ship; and to proceed with the two other boats, one under his own
command (in which he most kindly allowed me to accompany him), and one
under Mr. Hammond, to survey the western parts of the Beagle Channel,
and afterwards to return and visit the settlement.  The day to our
astonishment was overpoweringly hot, so that our skins were scorched:
with this beautiful weather, the view in the middle of the Beagle
Channel was very remarkable.  Looking towards either hand, no object
intercepted the vanishing points of this long canal between the
mountains.  The circumstance of its being an arm of the sea was
rendered very evident by several huge whales [2] spouting in different
directions.  On one occasion I saw two of these monsters, probably male
and female, slowly swimming one after the other, within less than a
stone's throw of the shore, over which the beech-tree extended its
branches. We sailed on till it was dark, and then pitched our tents in
a quiet creek.  The greatest luxury was to find for our beds a beach of
pebbles, for they were dry and yielded to the body.  Peaty soil is
damp; rock is uneven and hard; sand gets into one's meat, when cooked
and eaten boat-fashion; but when lying in our blanket-bags, on a good
bed of smooth pebbles, we passed most comfortable nights.

It was my watch till one o'clock.  There is something very solemn in
these scenes.  At no time does the consciousness in what a remote
corner of the world you are then standing, come so strongly before the
mind.  Everything tends to this effect; the stillness of the night is
interrupted only by the heavy breathing of the seamen beneath the
tents, and sometimes by the cry of a night-bird.  The occasional
barking of a dog, heard in the distance, reminds one that it is  the
land of the savage.

January 20th.--Early in the morning we arrived at the point where the
Beagle Channel divides into two arms; and we entered the northern one.
The scenery here becomes even grander than before.  The lofty mountains
on the north side compose the granitic axis, or backbone of the country
and boldly rise to a height of between three and four thousand feet,
with one peak above six thousand feet.  They are covered by a wide
mantle of perpetual snow, and numerous cascades pour their waters,
through the woods, into the narrow channel below.  In many parts,
magnificent glaciers extend from the mountain side to the water's edge.
It is scarcely possible to imagine anything more beautiful than the
beryl-like blue of these glaciers, and especially as contrasted with
the dead white of the upper expanse of snow. The fragments which had
fallen from the glacier into the water were floating away, and the
channel with its icebergs presented, for the space of a mile, a
miniature likeness of the Polar Sea.  The boats being hauled on shore
at our dinner-hour, we were admiring from the distance of half a mile a
perpendicular cliff of ice, and were wishing that some more fragments
would fall.  At last, down came a mass with a roaring noise, and
immediately we saw the smooth outline of a wave travelling towards us.
The men ran down as quickly as they could to the boats; for the chance
of their being dashed to pieces was evident.  One of the seamen just
caught hold of the bows, as the curling breaker reached it: he was
knocked over and over, but not hurt, and the boats though thrice lifted
on high and let fall again, received no damage.  This was most
fortunate for us, for we were a hundred miles distant from the ship,
and we should have been left without provisions or fire-arms.  I had
previously observed that some large fragments of rock on the beach had
been lately displaced; but until seeing this wave, I did not understand
the cause.  One side of the creek was formed by a spur of mica-slate;
the head by a cliff of ice about forty feet high; and the other side by
a promontory fifty feet high, built up of huge rounded fragments of
granite and mica-slate, out of which old trees were growing.  This
promontory was evidently a moraine, heaped up at a period when the
glacier had greater dimensions.

When we reached the western mouth of this northern branch of the Beagle
Channel, we sailed amongst many unknown desolate islands, and the
weather was wretchedly bad. We met with no natives.  The coast was
almost everywhere so steep, that we had several times to pull many
miles before we could find space enough to pitch our two tents: one
night we slept on large round boulders, with putrefying sea-weed
between them; and when the tide rose, we had to get up and move our
blanket-bags.  The farthest point westward which we reached was Stewart
Island, a distance of about one hundred and fifty miles from our ship.
We returned into the Beagle Channel by the southern arm, and thence
proceeded, with no adventure, back to Ponsonby Sound.

February 6th.--We arrived at Woollya.  Matthews gave so bad an account
of the conduct of the Fuegians, that Captain Fitz Roy determined to
take him back to the Beagle; and ultimately he was left at New Zealand,
where his brother was a missionary.  From the time of our leaving, a
regular system of plunder commenced; fresh parties of the natives kept
arriving: York and Jemmy lost many things, and Matthews almost
everything which had not been concealed underground. Every article
seemed to have been torn up and divided by the natives. Matthews
described the watch he was obliged always to keep as most harassing;
night and day he was surrounded by the natives, who tried to tire him
out by making an incessant noise close to his head.  One day an old
man, whom Matthews asked to leave his wigwam, immediately returned with
a large stone in his hand: another day a whole party came armed with
stones and stakes, and some of the younger men and Jemmy's brother were
crying: Matthews met them with presents.  Another party showed by signs
that they wished to strip him naked and pluck all the hairs out of his
face and body.  I think we arrived just in time to save his life.
Jemmy's relatives had been so vain and foolish, that they had showed to
strangers their plunder, and their manner of obtaining it.  It was
quite melancholy leaving the three Fuegians with their savage
countrymen; but it was a great comfort that they had no personal fears.
York, being a powerful resolute man, was pretty sure to get on well,
together with his wife Fuegia.  Poor Jemmy looked rather disconsolate,
and would then, I have little doubt, have been glad to have returned
with us.  His own brother had stolen many things from him; and as he
remarked, "What fashion call that:" he abused his countrymen, "all bad
men, no sabe (know) nothing" and, though I never heard him swear
before, "damned fools." Our three Fuegians, though they had been only
three years with civilized men, would, I am sure, have been glad to
have retained their new habits; but this was obviously impossible.  I
fear it is more than doubtful, whether their visit will have been of
any use to them.

In the evening, with Matthews on board, we made sail back to the ship,
not by the Beagle Channel, but by the southern coast.  The boats were
heavily laden and the sea rough, and we had a dangerous passage.  By
the evening of the 7th we were on board the Beagle after an absence of
twenty days, during which time we had gone three hundred miles in the
open boats.  On the 11th, Captain Fitz Roy paid a visit by himself to
the Fuegians and found them going on well; and that they had lost very
few more things.


On the last day of February in the succeeding year (1834) the Beagle
anchored in a beautiful little cove at the eastern entrance of the
Beagle Channel.  Captain Fitz Roy determined on the bold, and as it
proved successful, attempt to beat against the westerly winds by the
same route, which we had followed in the boats to the settlement at
Woollya. We did not see many natives until we were near Ponsonby Sound,
where we were followed by ten or twelve canoes.  The natives did not at
all understand the reason of our tacking, and, instead of meeting us at
each tack, vainly strove to follow us in our zigzag course.  I was
amused at finding what a difference the circumstance of being quite
superior in force made, in the interest of beholding these savages.
While in the boats I got to hate the very sound of their voices, so
much trouble did they give us.  The first and last word was
"yammerschooner." When, entering some quiet little cove, we have looked
round and thought to pass a quiet night, the odious word
"yammerschooner" has shrilly sounded from some gloomy nook, and then
the little signal-smoke has curled up to spread the news far and wide.
On leaving some place we have said to each other, "Thank heaven, we
have at last fairly left these wretches!" when one more faint hallo
from an all-powerful voice, heard at a prodigious distance, would reach
our ears, and clearly could we distinguish--"yammerschooner." But now,
the more Fuegians the merrier; and very merry work it was.  Both
parties laughing, wondering, gaping at each other; we pitying them, for
giving us good fish and crabs for rags, etc.; they grasping at the
chance of finding people so foolish as to exchange such splendid
ornaments for a good supper.  It was most amusing to see the
undisguised smile of satisfaction with which one young woman with her
face painted black, tied several bits of scarlet cloth round her head
with rushes.  Her husband, who enjoyed the very universal privilege in
this country of possessing two wives, evidently became jealous of all
the attention paid to his young wife; and, after a consultation with
his naked beauties, was paddled away by them.

Some of the Fuegians plainly showed that they had a fair notion of
barter.  I gave one man a large nail (a most valuable present) without
making any signs for a return; but he immediately picked out two fish,
and handed them up on the point of his spear.  If any present was
designed for one canoe, and it fell near another, it was invariably
given to the right owner.  The Fuegian boy, whom Mr. Low had on board
showed, by going into the most violent passion, that he quite
understood the reproach of being called a liar, which in truth he was.
We were this time, as on all former occasions, much surprised at the
little notice, or rather none whatever, which was taken of many things,
the use of which must have been evident to the natives.  Simple
circumstances--such as the beauty of scarlet cloth or blue beads, the
absence of women, our care in washing ourselves,--excited their
admiration far more than any grand or complicated object, such as our
ship.  Bougainville has well remarked concerning these people, that
they treat the "chefs d'oeuvre de l'industrie humaine, comme ils
traitent les loix de la nature et ses phenomenes."

On the 5th of March, we anchored in a cove at Woollya, but we saw not a
soul there.  We were alarmed at this, for the natives in Ponsonby Sound
showed by gestures, that there had been fighting; and we afterwards
heard that the dreaded Oens men had made a descent.  Soon a canoe, with
a little flag flying, was seen approaching, with one of the men in it
washing the paint off his face.  This man was poor Jemmy,--now a thin,
haggard savage, with long disordered hair, and naked, except a bit of
blanket round his waist.  We did not recognize him till he was close to
us, for he was ashamed of himself, and turned his back to the ship.  We
had left him plump, fat, clean, and well-dressed;--I never saw so
complete and grievous a change.  As soon, however, as he was clothed,
and the first flurry was over, things wore a good appearance. He dined
with Captain Fitz Roy, and ate his dinner as tidily as formerly.  He
told us that he had "too much" (meaning enough) to eat, that he was not
cold, that his relations were very good people, and that he did not
wish to go back to England: in the evening we found out the cause of
this great change in Jemmy's feelings, in the arrival of his young and
nice-looking wife.  With his usual good feeling he brought two
beautiful otter-skins for two of his best friends, and some spear-heads
and arrows made with his own hands for the Captain.  He said he had
built a canoe for himself, and he boasted that he could talk a little
of his own language!  But it is a most singular fact, that he appears
to have taught all his tribe some English: an old man spontaneously
announced "Jemmy Button's wife." Jemmy had lost all his property.  He
told us that York Minster had built a large canoe, and with his wife
Fuegia, [3] had several months since gone to his own country, and had
taken farewell by an act of consummate villainy; he persuaded Jemmy and
his mother to come with him, and then on the way deserted them by
night, stealing every article of their property.

Jemmy went to sleep on shore, and in the morning returned, and remained
on board till the ship got under way, which frightened his wife, who
continued crying violently till he got into his canoe.  He returned
loaded with valuable property.  Every soul on board was heartily sorry
to shake hands with him for the last time.  I do not now doubt that he
will be as happy as, perhaps happier than, if he had never left his own
country.  Every one must sincerely hope that Captain Fitz Roy's noble
hope may be fulfilled, of being rewarded for the many generous
sacrifices which he made for these Fuegians, by some shipwrecked sailor
being protected by the descendants of Jemmy Button and his tribe!  When
Jemmy reached the shore, he lighted a signal fire, and the smoke curled
up, bidding us a last and long farewell, as the ship stood on her
course into the open sea.

The perfect equality among the individuals composing the Fuegian tribes
must for a long time retard their civilization. As we see those
animals, whose instinct compels them to live in society and obey a
chief, are most capable of improvement, so is it with the races of
mankind.  Whether we look at it as a cause or a consequence, the more
civilized always have the most artificial governments.  For instance,
the inhabitants of Otaheite, who, when first discovered, were governed
by hereditary kings, had arrived at a far higher grade than another
branch of the same people, the New Zealanders,--who, although benefited
by being compelled to turn their attention to agriculture, were
republicans in the most absolute sense.  In Tierra del Fuego, until
some chief shall arise with power sufficient to secure any acquired
advantage, such as the domesticated animals, it seems scarcely possible
that the political state of the country can be improved.  At present,
even a piece of cloth given to one is torn into shreds and distributed;
and no one individual becomes richer than another.  On the other hand,
it is difficult to understand how a chief can arise till there is
property of some sort by which he might manifest his superiority and
increase his power.

I believe, in this extreme part of South America, man exists in a lower
state of improvement than in any other part of the world.  The South
Sea Islanders, of the two races inhabiting the Pacific, are
comparatively civilized.  The Esquimau in his subterranean hut, enjoys
some of the comforts of life, and in his canoe, when fully equipped,
manifests much skill.  Some of the tribes of Southern Africa prowling
about in search of roots, and living concealed on the wild and arid
plains, are sufficiently wretched.  The Australian, in the simplicity
of the arts of life, comes nearest the Fuegian: he can, however, boast
of his boomerang, his spear and throwing-stick, his method of climbing
trees, of tracking animals, and of hunting.  Although the Australian
may be superior in acquirements, it by no means follows that he is
likewise superior in mental capacity: indeed, from what I saw of the
Fuegians when on board and from what I have read of the Australians, I
should think the case was exactly the reverse.

[1] This substance, when dry, is tolerably compact, and of little
specific gravity: Professor Ehrenberg has examined it: he states (Konig
Akad. der Wissen: Berlin, Feb. 1845) that it is composed of infusoria,
including fourteen polygastrica, and four phytolitharia.  He says that
they are all inhabitants of fresh-water; this is a beautiful example of
the results obtainable through Professor Ehrenberg's microscopic
researches; for Jemmy Button told me that it is always collected at the
bottoms of mountain-brooks.  It is, moreover, a striking fact that in
the geographical distribution of the infusoria, which are well known to
have very wide ranges, that all the species in this substance, although
brought from the extreme southern point of Tierra del Fuego, are old,
known forms.

[2] One day, off the East coast of Tierra del Fuego, we saw a grand
sight in several spermaceti whales jumping upright quite out of the
water, with the exception of their tail-fins. As they fell down
sideways, they splashed the water high up, and the sound reverberated
like a distant broadside.

[3] Captain Sulivan, who, since his voyage in the Beagle, has been
employed on the survey of the Falkland Islands, heard from a sealer in
(1842?), that when in the western part of the Strait of Magellan, he
was astonished by a native woman coming on board, who could talk some
English.  Without doubt this was Fuega Basket.  She lived (I fear the
term probably bears a double interpretation) some days on board.



CHAPTER XI

STRAIT OF MAGELLAN.--CLIMATE OF THE SOUTHERN COASTS

Strait of Magellan--Port Famine--Ascent of Mount Tarn--Forests--Edible
Fungus--Zoology--Great Sea-weed--Leave Tierra del
Fuego--Climate--Fruit-trees and Productions of the Southern
Coasts--Height of Snow-line on the Cordillera--Descent of Glaciers to
the Sea--Icebergs formed--Transportal of Boulders--Climate and
Productions of the Antarctic Islands--Preservation of Frozen
Carcasses--Recapitulation.


IN THE end of May, 1834, we entered for a second time the eastern mouth
of the Strait of Magellan.  The country on both sides of this part of
the Strait consists of nearly level plains, like those of Patagonia.
Cape Negro, a little within the second Narrows, may be considered as
the point where the land begins to assume the marked features of Tierra
del Fuego.  On the east coast, south of the Strait, broken park-like
scenery in a like manner connects these two countries, which are
opposed to each other in almost every feature.  It is truly surprising
to find in a space of twenty miles such a change in the landscape.  If
we take a rather greater distance, as between Port Famine and Gregory
Bay, that is about sixty miles, the difference is still more wonderful.
At the former place, we have rounded mountains concealed by impervious
forests, which are drenched with the rain, brought by an endless
succession of gales; while at Cape Gregory, there is a clear and bright
blue sky over the dry and sterile plains.  The atmospheric currents,
[1] although rapid, turbulent, and unconfined by any apparent limits,
yet seem to follow, like a river in its bed, a regularly determined
course.

During our previous visit (in January), we had an interview at Cape
Gregory with the famous so-called gigantic Patagonians, who gave us a
cordial reception.  Their height appears greater than it really is,
from their large guanaco mantles, their long flowing hair, and general
figure: on an average, their height is about six feet, with some men
taller and only a few shorter; and the women are also tall; altogether
they are certainly the tallest race which we anywhere saw.  In features
they strikingly resemble the more northern Indians whom I saw with
Rosas, but they have a wilder and more formidable appearance: their
faces were much painted with red and black, and one man was ringed and
dotted with white like a Fuegian.  Captain Fitz Roy offered to take any
three of them on board, and all seemed determined to be of the three.
It was long before we could clear the boat; at last we got on board
with our three giants, who dined with the Captain, and behaved quite
like gentlemen, helping themselves with knives, forks, and spoons:
nothing was so much relished as sugar.  This tribe has had so much
communication with sealers and whalers that most of the men can speak a
little English and Spanish; and they are half civilized, and
proportionally demoralized.

The next morning a large party went on shore, to barter for skins and
ostrich-feathers; fire-arms being refused, tobacco was in greatest
request, far more so than axes or tools.  The whole population of the
toldos, men, women, and children, were arranged on a bank.  It was an
amusing scene, and it was impossible not to like the so-called giants,
they were so thoroughly good-humoured and unsuspecting: they asked us
to come again.  They seem to like to have Europeans to live with them;
and old Maria, an important woman in the tribe, once begged Mr. Low to
leave any one of his sailors with them.  They spend the greater part of
the year here; but in summer they hunt along the foot of the
Cordillera: sometimes they travel as far as the Rio Negro 750 miles to
the north.  They are well stocked with horses, each man having,
according to Mr. Low, six or seven, and all the women, and even
children, their one own horse.  In the time of Sarmiento (1580), these
Indians had bows and arrows, now long since disused; they then also
possessed some horses.  This is a very curious fact, showing the
extraordinarily rapid multiplication of horses in South America. The
horse was first landed at Buenos Ayres in 1537, and the colony being
then for a time deserted, the horse ran wild; [2] in 1580, only
forty-three years afterwards, we hear of them at the Strait of
Magellan!  Mr. Low informs me, that a neighbouring tribe of
foot-Indians is now changing into horse-Indians: the tribe at Gregory
Bay giving them their worn-out horses, and sending in winter a few of
their best skilled men to hunt for them.

June 1st.--We anchored in the fine bay of Port Famine. It was now the
beginning of winter, and I never saw a more cheerless prospect; the
dusky woods, piebald with snow, could be only seen indistinctly,
through a drizzling hazy atmosphere.  We were, however, lucky in
getting two fine days.  On one of these, Mount Sarmiento, a distant
mountain 6800 feet high, presented a very noble spectacle.  I was
frequently surprised in the scenery of Tierra del Fuego, at the little
apparent elevation of mountains really lofty.  I suspect it is owing to
a cause which would not at first be imagined, namely, that the whole
mass, from the summit to the water's edge, is generally in full view. I
remember having seen a mountain, first from the Beagle Channel, where
the whole sweep from the summit to the base was full in view, and then
from Ponsonby Sound across several successive ridges; and it was
curious to observe in the latter case, as each fresh ridge afforded
fresh means of judging of the distance, how the mountain rose in height.

Before reaching Port Famine, two men were seen running along the shore
and hailing the ship.  A boat was sent for them.  They turned out to be
two sailors who had run away from a sealing-vessel, and had joined the
Patagonians.  These Indians had treated them with their usual
disinterested hospitality.  They had parted company through accident,
and were then proceeding to Port Famine in hopes of finding some ship.
I dare say they were worthless vagabonds, but I never saw more
miserable-looking ones.  They had been living for some days on
mussel-shells and berries, and their tattered clothes had been burnt by
sleeping so near their fires. They had been exposed night and day,
without any shelter, to the late incessant gales, with rain, sleet, and
snow, and yet they were in good health.

During our stay at Port Famine, the Fuegians twice came and plagued us.
As there were many instruments, clothes, and men on shore, it was
thought necessary to frighten them away.  The first time a few great
guns were fired, when they were far distant.  It was most ludicrous to
watch through a glass the Indians, as often as the shot struck the
water, take up stones, and, as a bold defiance, throw them towards the
ship, though about a mile and a half distant!  A boat was sent with
orders to fire a few musket-shots wide of them. The Fuegians hid
themselves behind the trees, and for every discharge of the muskets
they fired their arrows; all, however, fell short of the boat, and the
officer as he pointed at them laughed.  This made the Fuegians frantic
with passion, and they shook their mantles in vain rage.  At last,
seeing the balls cut and strike the trees, they ran away, and we were
left in peace and quietness.  During the former voyage the Fuegians
were here very troublesome, and to frighten them a rocket was fired at
night over their wigwams; it answered effectually, and one of the
officers told me that the clamour first raised, and the barking of the
dogs, was quite ludicrous in contrast with the profound silence which
in a minute or two afterwards prevailed.  The next morning not a single
Fuegian was in the neighbourhood.

When the Beagle was here in the month of February, I started one
morning at four o'clock to ascend Mount Tarn, which is 2600 feet high,
and is the most elevated point in this immediate district.  We went in
a boat to the foot of the mountain (but unluckily not to the best
part), and then began our ascent.  The forest commences at the line of
high-water mark, and during the first two hours I gave over all hopes
of reaching the summit.  So thick was the wood, that it was necessary
to have constant recourse to the compass; for every landmark, though in
a mountainous country, was completely shut out.  In the deep ravines,
the death-like scene of desolation exceeded all description; outside it
was blowing a gale, but in these hollows, not even a breath of wind
stirred the leaves of the tallest trees.  So gloomy, cold, and wet was
every part, that not even the fungi, mosses, or ferns could flourish.
In the valleys it was scarcely possible to crawl along, they were so
completely barricaded by great mouldering trunks, which had fallen down
in every direction. When passing over these natural bridges, one's
course was often arrested by sinking knee deep into the rotten wood; at
other times, when attempting to lean against a firm tree, one was
startled by finding a mass of decayed matter ready to fall at the
slightest touch.  We at last found ourselves among the stunted trees,
and then soon reached the bare ridge, which conducted us to the summit.
Here was a view characteristic of Tierra del Fuego; irregular chains of
hills, mottled with patches of snow, deep yellowish-green valleys, and
arms of the sea intersecting the land in many directions.  The strong
wind was piercingly cold, and the atmosphere rather hazy, so that we
did not stay long on the top of the mountain.  Our descent was not
quite so laborious as our ascent, for the weight of the body forced a
passage, and all the slips and falls were in the right direction.

I have already mentioned the sombre and dull character of the evergreen
forests, [3] in which two or three species of trees grow, to the
exclusion of all others.  Above the forest land, there are many dwarf
alpine plants, which all spring from the mass of peat, and help to
compose it: these plants are very remarkable from their close alliance
with the species growing on the mountains of Europe, though so many
thousand miles distant.  The central part of Tierra del Fuego, where
the clay-slate formation occurs, is most favourable to the growth of
trees; on the outer coast the poorer granitic soil, and a situation
more exposed to the violent winds, do not allow of their attaining any
great size.  Near Port Famine I have seen more large trees than
anywhere else: I measured a Winter's Bark which was four feet six
inches in girth, and several of the beech were as much as thirteen
feet.  Captain King also mentions a beech which was seven feet in
diameter, seventeen feet above the roots.

There is one vegetable production deserving notice from its importance
as an article of food to the Fuegians.  It is a globular, bright-yellow
fungus, which grows in vast numbers on the beech-trees.  When young it
is elastic and turgid, with

[picture]

a smooth surface; but when mature it shrinks, becomes tougher, and has
its entire surface deeply pitted or honey-combed, as represented in the
accompanying woodcut.  This fungus belongs to a new and curious genus,
[4] I found a second species on another species of beech in Chile: and
Dr. Hooker informs me, that just lately a third species has been
discovered on a third species of beech in Van Diernan's Land.  How
singular is this relationship between parasitical fungi and the trees
on which they grow, in distant parts of the world!  In Tierra del Fuego
the fungus in its tough and mature state is collected in large
quantities by the women and children, and is eaten un-cooked.  It has a
mucilaginous, slightly sweet taste, with a faint smell like that of a
mushroom.  With the exception of a few berries, chiefly of a dwarf
arbutus, the natives eat no vegetable food besides this fungus.  In New
Zealand, before the introduction of the potato, the roots of the fern
were largely consumed; at the present time, I believe, Tierra del Fuego
is the only country in the world where a cryptogamic plant affords a
staple article of food.

The zoology of Tierra del Fuego, as might have been expected from the
nature of its climate and vegetation, is very poor.  Of mammalia,
besides whales and seals, there is one bat, a kind of mouse (Reithrodon
chinchilloides), two true mice, a ctenomys allied to or identical with
the tucutuco, two foxes (Canis Magellanicus and C. Azarae), a
sea-otter, the guanaco, and a deer.  Most of these animals inhabit only
the drier eastern parts of the country; and the deer has never been
seen south of the Strait of Magellan.  Observing the general
correspondence of the cliffs of soft sandstone, mud, and shingle, on
the opposite sides of the Strait, and on some intervening islands, one
is strongly tempted to believe that the land was once joined, and thus
allowed animals so delicate and helpless as the tucutuco and Reithrodon
to pass over. The correspondence of the cliffs is far from proving any
junction; because such cliffs generally are formed by the intersection
of sloping deposits, which, before the elevation of the land, had been
accumulated near the then existing shores.  It is, however, a
remarkable coincidence, that in the two large islands cut off by the
Beagle Channel from the rest of Tierra del Fuego, one has cliffs
composed of matter that may be called stratified alluvium, which front
similar ones on the opposite side of the channel,--while the other is
exclusively bordered by old crystalline rocks: in the former, called
Navarin Island, both foxes and guanacos occur; but in the latter, Hoste
Island, although similar in every respect, and only separated by a
channel a little more than half a mile wide, I have the word of Jemmy
Button for saying that neither of these animals are found.

The gloomy woods are inhabited by few birds: occasionally the plaintive
note of a white-tufted tyrant-flycatcher (Myiobius albiceps) may be
heard, concealed near the summit of the most lofty trees; and more
rarely the loud strange cry of a black wood-pecker, with a fine scarlet
crest on its head.  A little, dusky-coloured wren (Scytalopus
Magellanicus) hops in a skulking manner among the entangled mass of the
fallen and decaying trunks.  But the creeper (Oxyurus tupinieri) is the
commonest bird in the country.  Throughout the beech forests, high up
and low down, in the most gloomy, wet, and impenetrable ravines, it may
be met with. This little bird no doubt appears more numerous than it
really is, from its habit of following with seeming curiosity any
person who enters these silent woods: continually uttering a harsh
twitter, it flutters from tree to tree, within a few feet of the
intruder's face.  It is far from wishing for the modest concealment of
the true creeper (Certhia familiaris); nor does it, like that bird, run
up the trunks of trees, but industriously, after the manner of a
willow-wren, hops about, and searches for insects on every twig and
branch.  In the more open parts, three or four species of finches, a
thrush, a starling (or Icterus), two Opetiorhynchi, and several hawks
and owls occur.

The absence of any species whatever in the whole class of Reptiles, is
a marked feature in the zoology of this country, as well as in that of
the Falkland Islands.  I do not ground this statement merely on my own
observation, but I heard it from the Spanish inhabitants of the latter
place, and from Jemmy Button with regard to Tierra del Fuego.  On the
banks of the Santa Cruz, in 50 degs.  south, I saw a frog; and it is
not improbable that these animals, as well as lizards, may be found as
far south as the Strait of Magellan, where the country retains the
character of Patagonia; but within the damp and cold limit of Tierra
del Fuego not one occurs. That the climate would not have suited some
of the orders, such as lizards, might have been foreseen; but with
respect to frogs, this was not so obvious.

Beetles occur in very small numbers: it was long before I could believe
that a country as large as Scotland, covered with vegetable productions
and with a variety of stations, could be so unproductive.  The few
which I found were alpine species (Harpalidae and Heteromidae) living
under stones.  The vegetable-feeding Chrysomelidae, so eminently
characteristic of the Tropics, are here almost entirely absent; [5] I
saw very few flies, butterflies, or bees, and no crickets or
Orthoptera.  In the pools of water I found but a few aquatic beetles,
and not any fresh-water shells: Succinea at first appears an exception;
but here it must be called a terrestrial shell, for it lives on the
damp herbage far from the water.  Land-shells could be procured only in
the same alpine situations with the beetles.  I have already contrasted
the climate as well as the general appearance of Tierra del Fuego with
that of Patagonia; and the difference is strongly exemplified in the
entomology.  I do not believe they have one species in common;
certainly the general character of the insects is widely different.

If we turn from the land to the sea, we shall find the latter as
abundantly stocked with living creatures as the former is poorly so. In
all parts of the world a rocky and partially protected shore perhaps
supports, in a given space, a greater number of individual animals than
any other station.  There is one marine production which, from its
importance, is worthy of a particular history.  It is the kelp, or
Macrocystis pyrifera.  This plant grows on every rock from low-water
mark to a great depth, both on the outer coast and within the channels.
[6] I believe, during the voyages of the Adventure and Beagle, not one
rock near the surface was discovered which was not buoyed by this
floating weed.  The good service it thus affords to vessels navigating
near this stormy land is evident; and it certainly has saved many a one
from being wrecked.  I know few things more surprising than to see this
plant growing and flourishing amidst those great breakers of the
western ocean, which no mass of rock, let it be ever so hard, can long
resist.  The stem is round, slimy, and smooth, and seldom has a
diameter of so much as an inch.  A few taken together are sufficiently
strong to support the weight of the large loose stones, to which in the
inland channels they grow attached; and yet some of these stones were
so heavy that when drawn to the surface, they could scarcely be lifted
into a boat by one person.  Captain Cook, in his second voyage, says,
that this plant at Kerguelen Land rises from a greater depth than
twenty-four fathoms; "and as it does not grow in a perpendicular
direction, but makes a very acute angle with the bottom, and much of it
afterwards spreads many fathoms on the surface of the sea, I am well
warranted to say that some of it grows to the length of sixty fathoms
and upwards." I do not suppose the stem of any other plant attains so
great a length as three hundred and sixty feet, as stated by Captain
Cook.  Captain Fitz Roy, moreover, found it growing [7] up from the
greater depth of forty-five fathoms.  The beds of this sea-weed, even
when of not great breadth, make excellent natural floating breakwaters.
It is quite curious to see, in an exposed harbour, how soon the waves
from the open sea, as they travel through the straggling stems, sink in
height, and pass into smooth water.

The number of living creatures of all Orders, whose existence
intimately depends on the kelp, is wonderful.  A great volume might be
written, describing the inhabitants of one of these beds of sea-weed.
Almost all the leaves, excepting those that float on the surface, are
so thickly incrusted with corallines as to be of a white colour.  We
find exquisitely delicate structures, some inhabited by simple
hydra-like polypi, others by more organized kinds, and beautiful
compound Ascidiae.  On the leaves, also, various patelliform shells,
Trochi, uncovered molluscs, and some bivalves are attached. Innumerable
crustacea frequent every part of the plant.  On shaking the great
entangled roots, a pile of small fish, shells, cuttle-fish, crabs of
all orders, sea-eggs, star-fish, beautiful Holuthuriae, Planariae, and
crawling nereidous animals of a multitude of forms, all fall out
together.  Often as I recurred to a branch of the kelp, I never failed
to discover animals of new and curious structures.  In Chiloe, where
the kelp does not thrive very well, the numerous shells, corallines,
and crustacea are absent; but there yet remain a few of the
Flustraceae, and some compound Ascidiae; the latter, however, are of
different species from those in Tierra del Fuego: we see here the fucus
possessing a wider range than the animals which use it as an abode.  I
can only compare these great aquatic forests of the southern hemisphere
with the terrestrial ones in the intertropical regions.  Yet if in any
country a forest was destroyed, I do not believe nearly so many species
of animals would perish as would here, from the destruction of the
kelp.  Amidst the leaves of this plant numerous species of fish live,
which nowhere else could find food or shelter; with their destruction
the many cormorants and other fishing birds, the otters, seals, and
porpoises, would soon perish also; and lastly, the Fuegian savage, the
miserable lord of this miserable land, would redouble his cannibal
feast, decrease in numbers, and perhaps cease to exist.

June 8th.--We weighed anchor early in the morning and left Port Famine.
Captain Fitz Roy determined to leave the Strait of Magellan by the
Magdalen Channel, which had not long been discovered.  Our course lay
due south, down that gloomy passage which I have before alluded to as
appearing to lead to another and worse world.  The wind was fair, but
the atmosphere was very thick; so that we missed much curious scenery.
The dark ragged clouds were rapidly driven over the mountains, from
their summits nearly down to their bases.  The glimpses which we caught
through the dusky mass were highly interesting; jagged points, cones of
snow, blue glaciers, strong outlines, marked on a lurid sky, were seen
at different distances and heights.  In the midst of such scenery we
anchored at Cape Turn, close to Mount Sarmiento, which was then hidden
in the clouds.  At the base of the lofty and almost perpendicular sides
of our little cove there was one deserted wigwam, and it alone reminded
us that man sometimes wandered into these desolate regions. But it
would be difficult to imagine a scene where he seemed to have fewer
claims or less authority.  The inanimate works of nature--rock, ice,
snow, wind, and water--all warring with each other, yet combined
against man--here reigned in absolute sovereignty.

June 9th.--In the morning we were delighted by seeing the veil of mist
gradually rise from Sarmiento, and display it to our view.  This
mountain, which is one of the highest in Tierra del Fuego, has an
altitude of 6800 feet.  Its base, for about an eighth of its total
height, is clothed by dusky woods, and above this a field of snow
extends to the summit.  These vast piles of snow, which never melt, and
seem destined to last as long as the world holds together, present a
noble and even sublime spectacle.  The outline of the mountain was
admirably clear and defined.  Owing to the abundance of light reflected
from the white and glittering surface, no shadows were cast on any
part; and those lines which intersected the sky could alone be
distinguished: hence the mass stood out in the boldest relief.  Several
glaciers descended in a winding course from the upper great expanse of
snow to the sea-coast: they may be likened to great frozen Niagaras;
and perhaps these cataracts of blue ice are full as beautiful as the
moving ones of water.  By night we reached the western part of the
channel; but the water was so deep that no anchorage could be found. We
were in consequence obliged to stand off and on in this narrow arm of
the sea, during a pitch-dark night of fourteen hours long.

June 10th.--In the morning we made the best of our way into the open
Pacific.  The western coast generally consists of low, rounded, quite
barren hills of granite and greenstone. Sir J. Narborough called one
part South Desolation, because it is "so desolate a land to behold:"
and well indeed might he say so.  Outside the main islands, there are
numberless scattered rocks on which the long swell of the open ocean
incessantly rages.  We passed out between the East and West Furies; and
a little farther northward there are so many breakers that the sea is
called the Milky Way.  One sight of such a coast is enough to make a
landsman dream for a week about shipwrecks, peril, and death; and with
this sight we bade farewell for ever to Tierra del Fuego.

The following discussion on the climate of the southern parts of the
continent with relation to its productions, on the snow-line, on the
extraordinarily low descent of the glaciers, and on the zone of
perpetual congelation in the antarctic islands, may be passed over by
any one not interested in these curious subjects, or the final
recapitulation alone may be read.  I shall, however, here give only an
abstract, and must refer for details to the Thirteenth Chapter and the
Appendix of the former edition of this work.

On the Climate and Productions of Tierra del Fuego and of the
South-west Coast.--The following table gives the mean temperature of
Tierra del Fuego, the Falkland Islands, and, for comparison, that of
Dublin:--

                                 Summer   Winter   Mean of Summer
                     Latitude    Temp.    Temp.    and Winter
  ---------------------------------------------------------------
  Tierra del Fuego   53 38' S.   50       33.08    41.54
  Falkland Islands   51 38' S.   51       --       --
  Dublin             53 21' N.   59.54    39.2     49.37


Hence we see that the central part of Tierra del Fuego is colder in
winter, and no less than 9.5 degs. less hot in summer, than Dublin.
According to von Buch, the mean temperature of July (not the hottest
month in the year) at Saltenfiord in Norway, is as high as 57.8 degs.,
and this place is actually 13 degs. nearer the pole than Port Famine!
[8] Inhospitable as this climate appears to our feelings evergreen
trees flourish luxuriantly under it.  Humming-birds may be seen sucking
the flowers, and parrots feeding on the seeds of the Winter's Bark, in
lat. 55 degs. S. I have already remarked to what a degree the sea
swarms with living creatures; and the shells (such as the Patellae,
Fissurellae, Chitons, and Barnacles), according to Mr. G. B. Sowerby,
are of a much larger size and of a more vigorous growth, than the
analogous species in the northern hemisphere.  A large Voluta is
abundant in southern Tierra del Fuego and the Falkland Islands.  At
Bahia Blanca, in lat. 39 degs. S., the most abundant shells were three
species of Oliva (one of large size), one or two Volutas, and a
Terebra.  Now, these are amongst the best characterized tropical forms.
It is doubtful whether even one small species of Oliva exists on the
southern shores of Europe, and there are no species of the two other
genera. If a geologist were to find in lat 39 degs. on the coast of
Portugal a bed containing numerous shells belonging to three species of
Oliva, to a Voluta and Terebra, he would probably assert that the
climate at the period of their existence must have been tropical; but
judging from South America, such an inference might be erroneous.

The equable, humid, and windy climate of Tierra del Fuego extends, with
only a small increase of heat, for many degrees along the west coast of
the continent.  The forests for 600 miles northward of Cape Horn, have
a very similar aspect.  As a proof of the equable climate, even for 300
or 400 miles still further northward, I may mention that in Chiloe
(corresponding in latitude with the northern parts of Spain) the peach
seldom produces fruit, whilst strawberries and apples thrive to
perfection.  Even the crops of barley and wheat [9] are often brought
into the houses to be dried and ripened.  At Valdivia (in the same
latitude of 40 degs., with Madrid) grapes and figs ripen, but are not
common; olives seldom ripen even partially, and oranges not at all.
These fruits, in corresponding latitudes in Europe, are well known to
succeed to perfection; and even in this continent, at the Rio Negro,
under nearly the same parallel with Valdivia, sweet potatoes
(convolvulus) are cultivated; and grapes, figs, olives, oranges, water
and musk melons, produce abundant fruit.  Although the humid and
equable climate of Chiloe, and of the coast northward and southward of
it, is so unfavourable to our fruits, yet the native forests, from lat.
45 to 38 degs., almost rival in luxuriance those of the glowing
intertropical regions.  Stately trees of many kinds, with smooth and
highly coloured barks, are loaded by parasitical monocotyledonous
plants; large and elegant ferns are numerous, and arborescent grasses
entwine the trees into one entangled mass to the height of thirty or
forty feet above the ground.  Palm-trees grow in lat 37 degs.; an
arborescent grass, very like a bamboo, in 40 degs.; and another closely
allied kind, of great length, but not erect, flourishes even as far
south as 45 degs. S.

An equable climate, evidently due to the large area of sea compared
with the land, seems to extend over the greater part of the southern
hemisphere; and, as a consequence, the vegetation partakes of a
semi-tropical character.  Tree-ferns thrive luxuriantly in Van Diemen's
Land (lat. 45 degs.), and I measured one trunk no less than six feet in
circumference. An arborescent fern was found by Forster in New Zealand
in 46 degs., where orchideous plants are parasitical on the trees.  In
the Auckland Islands, ferns, according to Dr. Dieffenbach [10] have
trunks so thick and high that they may be almost called tree-ferns; and
in these islands, and even as far south as lat. 55 degs. in the
Macquarrie Islands, parrots abound.

On the Height of the Snow-line, and on the Descent of the Glaciers in
South America.--For the detailed authorities for the following table, I
must refer to the former edition:--

                                   Height in feet
  Latitude                         of Snow-line    Observer
  ----------------------------------------------------------------
  Equatorial region; mean result   15,748           Humboldt. Bolivia,
  lat. 16 to 18 degs. S.           17,000           Pentland. Central Chile,
  lat. 33 degs. S.             14,500 - 15,000      Gillies, and
                                                    the Author.
  Chiloe, lat. 41 to 43 degs. S.   6,000            Officers of the
                                                    Beagle and the
                                                    Author.
  Tierra del Fuego, 54 degs. S.    3,500 - 4,000    King.


As the height of the plane of perpetual snow seems chiefly to be
determined by the extreme heat of the summer, rather than by the mean
temperature of the year, we ought not to be surprised at its descent in
the Strait of Magellan, where the summer is so cool, to only 3500 or
4000 feet above the level of the sea; although in Norway, we must
travel to between lat. 67 and 70 degs. N., that is, about 14 degs.
nearer the pole, to meet with perpetual snow at this low level.  The
difference in height, namely, about 9000 feet, between the snow-line on
the Cordillera behind Chiloe (with its highest points ranging from only
5600 to 7500 feet) and in central Chile [11] (a distance of only 9
degs. of latitude), is truly wonderful.  The land from the southward of
Chiloe to near Concepcion (lat. 37 degs.) is hidden by one dense forest
dripping with moisture.  The sky is cloudy, and we have seen how badly
the fruits of southern Europe succeed.  In central Chile, on the other
hand, a little northward of Concepcion, the sky is generally clear,
rain does not fall for the seven summer months, and southern European
fruits succeed admirably; and even the sugar-cane has been cultivated.
[12] No doubt the plane of perpetual snow undergoes the above
remarkable flexure of 9000 feet, unparalleled in other parts of the
world, not far from the latitude of Concepcion, where the land ceases
to be covered with forest-trees; for trees in South America indicate a
rainy climate, and rain a clouded sky and little heat in summer.

The descent of glaciers to the sea must, I conceive, mainly depend
(subject, of course, to a proper supply of snow in the upper region) on
the lowness of the line of perpetual snow on steep mountains near the
coast.  As the snow-line is so low in Tierra del Fuego, we might have
expected that many of the glaciers would have reached the sea.
Nevertheless, I was astonished when I first saw a range, only from 3000
to 4000 feet in height, in the latitude of Cumberland, with every
valley filled with streams of ice descending to the sea-coast. Almost
every arm of the sea, which penetrates to the interior higher chain,
not only in Tierra del Fuego, but on the coast for 650 miles
northwards, is terminated by "tremendous and astonishing glaciers," as
described by one of the officers on the survey.  Great masses of ice
frequently fall from these icy cliffs, and the crash reverberates like
the broadside of a man-of-war through the lonely channels.  These
falls, as noticed in the last chapter, produce great waves which break
on the adjoining coasts.  It is known that earthquakes frequently cause
masses of earth to fall from sea-cliffs: how terrific, then, would be
the effect of a severe shock (and such occur here [13]) on a body like
a glacier, already in motion, and traversed by fissures!  I can readily
believe that the water would be fairly beaten back out of the deepest
channel, and then, returning with an overwhelming force, would whirl
about huge masses of rock like so much chaff.  In Eyre's Sound, in the
latitude of Paris, there are immense glaciers, and yet the loftiest
neighbouring mountain is only 6200 feet high.  In this Sound, about
fifty icebergs were seen at one time floating outwards, and one of them
must have been at least 168 feet in total height.  Some of the icebergs
were loaded with blocks of no inconsiderable size, of granite and other
rocks, different from the clay-slate of the surrounding mountains.  The
glacier furthest from the pole, surveyed during the voyages of the
Adventure and Beagle, is in lat. 46 degs. 50', in the Gulf of Penas. It
is 15 miles long, and in one part 7 broad and descends to the
sea-coast.  But even a few miles northward of this glacier, in Laguna
de San

[picture]

Rafael, some Spanish missionaries [14] encountered "many icebergs, some
great, some small, and others middle-sized," in a narrow arm of the
sea, on the 22nd of the month corresponding with our June, and in a
latitude corresponding with that of the Lake of Geneva!

In Europe, the most southern glacier which comes down to the sea is met
with, according to Von Buch, on the coast of Norway, in lat. 67 degs.
Now, this is more than 20 degs. of latitude, or 1230 miles, nearer the
pole than the Laguna de San Rafael.  The position of the glaciers at
this place and in the Gulf of Penas may be put even in a more striking
point of view, for they descend to the sea-coast within 7.5 degs. of
latitude, or 450 miles, of a harbour, where three species of Oliva, a
Voluta, and a Terebra, are the commonest shells, within less than 9
degs. from where palms grow, within 4.5 degs. of a region where the
jaguar and puma range over the plains, less than 2.5 degs. from
arborescent grasses, and (looking to the westward in the same
hemisphere) less than 2 degs. from orchideous parasites, and within a
single degree of tree-ferns!

These facts are of high geological interest with respect to the climate
of the northern hemisphere at the period when boulders were
transported.  I will not here detail how simply the theory of icebergs
being charged with fragments of rock, explain the origin and position
of the gigantic boulders of eastern Tierra del Fuego, on the high plain
of Santa Cruz, and on the island of Chiloe.  In Tierra del Fuego, the
greater number of boulders lie on the lines of old sea-channels, now
converted into dry valleys by the elevation of the land.  They are
associated with a great unstratified formation of mud and sand,
containing rounded and angular fragments of all sizes, which has
originated [15] in the repeated ploughing up of the sea-bottom by the
stranding of icebergs, and by the matter transported on them.  Few
geologists now doubt that those erratic boulders which lie near lofty
mountains have been pushed forward by the glaciers themselves, and that
those distant from mountains, and embedded in subaqueous deposits, have
been conveyed thither either on icebergs or frozen in coast-ice.  The
connection between the transportal of boulders and the presence of ice
in some form, is strikingly shown by their geographical distribution
over the earth. In South America they are not found further than 48
degs. of latitude, measured from the southern pole; in North America it
appears that the limit of their transportal extends to 53.5 degs. from
the northern pole; but in Europe to not more than 40 degs. of latitude,
measured from the same point.  On the other hand, in the intertropical
parts of America, Asia, and Africa, they have never been observed; nor
at the Cape of Good Hope, nor in Australia. [16]

On the Climate and Productions of the Antarctic Islands.--Considering
the rankness of the vegetation in Tierra del Fuego, and on the coast
northward of it, the condition of the islands south and south-west of
America is truly surprising. Sandwich Land, in the latitude of the
north part of Scotland, was found by Cook, during the hottest month of
the year, "covered many fathoms thick with everlasting snow;" and there
seems to be scarcely any vegetation.  Georgia, an island 96 miles long
and 10 broad, in the latitude of Yorkshire, "in the very height of
summer, is in a manner wholly covered with frozen snow." It can boast
only of moss, some tufts of grass, and wild burnet; it has only one
land-bird (Anthus correndera), yet Iceland, which is 10 degs. nearer
the pole, has, according to Mackenzie, fifteen land-birds.  The South
Shetland Islands, in the same latitude as the southern half of Norway,
possess only some lichens, moss, and a little grass; and Lieut. Kendall
[17] found the bay, in which he was at anchor, beginning to freeze at a
period corresponding with our 8th of September.  The soil here consists
of ice and volcanic ashes interstratified; and at a little depth
beneath the surface it must remain perpetually congealed, for Lieut.
Kendall found the body of a foreign sailor which had long been buried,
with the flesh and all the features perfectly preserved.  It is a
singular fact, that on the two great continents in the northern
hemisphere (but not in the broken land of Europe between them ), we
have the zone of perpetually frozen under-soil in a low
latitude--namely, in 56 degs. in North America at the depth of three
feet, [18] and in 62 degs. in Siberia at the depth of twelve to fifteen
feet--as the result of a directly opposite condition of things to those
of the southern hemisphere.  On the northern continents, the winter is
rendered excessively cold by the radiation from a large area of land
into a clear sky, nor is it moderated by the warmth-bringing currents
of the sea; the short summer, on the other hand, is hot.  In the
Southern Ocean the winter is not so excessively cold, but the summer is
far less hot, for the clouded sky seldom allows the sun to warm the
ocean, itself a bad absorbent of heat: and hence the mean temperature
of the year, which regulates the zone of perpetually congealed
under-soil, is low.  It is evident that a rank vegetation, which does
not so much require heat as it does protection from intense cold, would
approach much nearer to this zone of perpetual congelation under the
equable climate of the southern hemisphere, than under the extreme
climate of the northern continents.

The case of the sailor's body perfectly preserved in the icy soil of
the South Shetland Islands (lat. 62 to 63 degs. S.), in a rather lower
latitude than that (lat. 64 degs. N.) under which Pallas found the
frozen rhinoceros in Siberia, is very interesting.  Although it is a
fallacy, as I have endeavoured to show in a former chapter, to suppose
that the larger quadrupeds require a luxuriant vegetation for their
support, nevertheless it is important to find in the South Shetland
Islands a frozen under-soil within 360 miles of the forest-clad islands
near Cape Horn, where, as far as the _bulk_ of vegetation is concerned,
any number of great quadrupeds might be supported. The perfect
preservation of the carcasses of the Siberian elephants and
rhinoceroses is certainly one of the most wonderful facts in geology;
but independently of the imagined difficulty of supplying them with
food from the adjoining countries, the whole case is not, I think, so
perplexing as it has generally been considered.  The plains of Siberia,
like those of the Pampas, appear to have been formed under the sea,
into which rivers brought down the bodies of many animals; of the
greater number of these, only the skeletons have been preserved, but of
others the perfect carcass.  Now, it is known that in the shallow sea
on the Arctic coast of America the bottom freezes, [19] and does not
thaw in spring so soon as the surface of the land, moreover at greater
depths, where the bottom of the sea does not freeze the mud a few feet
beneath the top layer might remain even in summer below 32 degs., as in
the case on the land with the soil at the depth of a few feet.  At
still greater depths, the temperature of the mud and water would
probably not be low enough to preserve the flesh; and hence, carcasses
drifted beyond the shallow parts near an Arctic coast, would have only
their skeletons preserved: now in the extreme northern parts of Siberia
bones are infinitely numerous, so that even islets are said to be
almost composed of them; [20] and those islets lie no less than ten
degrees of latitude north of the place where Pallas found the frozen
rhinoceros.  On the other hand, a carcass washed by a flood into a
shallow part of the Arctic Sea, would be preserved for an indefinite
period, if it were soon afterwards covered with mud sufficiently thick
to prevent the heat of the summer-water penetrating to it; and if, when
the sea-bottom was upraised into land, the covering was sufficiently
thick to prevent the heat of the summer air and sun thawing and
corrupting it.

Recapitulation.--I will recapitulate the principal facts with regard to
the climate, ice-action, and organic productions of the southern
hemisphere, transposing the places in imagination to Europe, with which
we are so much better acquainted. Then, near Lisbon, the commonest
sea-shells, namely, three species of Oliva, a Voluta, and a Terebra,
would have a tropical character.  In the southern provinces of France,
magnificent forests, intwined by arborescent grasses and with the trees
loaded with parasitical plants, would hide the face of the land.  The
puma and the jaguar would haunt the Pyrenees.  In the latitude of Mont
Blanc, but on an island as far westward as Central North America,
tree-ferns and parasitical Orchideae would thrive amidst the thick
woods. Even as far north as central Denmark, humming-birds would be
seen fluttering about delicate flowers, and parrots feeding amidst the
evergreen woods; and in the sea there, we should have a Voluta, and all
the shells of large size and vigorous growth.  Nevertheless, on some
islands only 360 miles northward of our new Cape Horn in Denmark, a
carcass buried in the soil (or if washed into a shallow sea, and
covered up with mud) would be preserved perpetually frozen.  If some
bold navigator attempted to penetrate northward of these islands, he
would run a thousand dangers amidst gigantic icebergs, on some of which
he would see great blocks of rock borne far away from their original
site.  Another island of large size in the latitude of southern
Scotland, but twice as far to the west, would be "almost wholly covered
with everlasting snow," and would have each bay terminated by
ice-cliffs, whence great masses would be yearly detached: this island
would boast only of a little moss, grass, and burnet, and a titlark
would be its only land inhabitant.  From our new Cape Horn in Denmark,
a chain of mountains, scarcely half the height of the Alps, would run
in a straight line due southward; and on its western flank every deep
creek of the sea, or fiord, would end in "bold and astonishing
glaciers." These lonely channels would frequently reverberate with the
falls of ice, and so often would great waves rush along their coasts;
numerous icebergs, some as tall as cathedrals, and occasionally loaded
with "no inconsiderable blocks of rock," would be stranded on the
outlying islets; at intervals violent earthquakes would shoot
prodigious masses of ice into the waters below.  Lastly, some
missionaries attempting to penetrate a long arm of the sea, would
behold the not lofty surrounding mountains, sending down their many
grand icy streams to the sea-coast, and their progress in the boats
would be checked by the innumerable floating icebergs, some small and
some great; and this would have occurred on our twenty-second of June,
and where the Lake of Geneva is now spread out! [21]

[1] The south-westerly breezes are generally very dry. January 29th,
being at anchor under Cape Gregory: a very hard gale from W. by S.,
clear sky with few cumuli; temperature 57 degs., dew-point 36
degs.,--difference 21 degs. On January 15th, at Port St. Julian: in the
morning, light winds with much rain, followed by a very heavy squall
with rain,--settled into heavy gale with large cumuli,--cleared up,
blowing very strong from S.S.W. Temperature 60 degs., dew-point 42
degs.,--difference 18 degs.

[2] Rengger, Natur. der Saeugethiere von Paraguay. S. 334.

[3] Captain Fitz Roy informs me that in April (our October), the leaves
of those trees which grow near the base of the mountains change colour,
but not those on the more elevated parts.  I remember having read some
observations, showing that in England the leaves fall earlier in a warm
and fine autumn than in a late and cold one, The change in the colour
being here retarded in the more elevated, and therefore colder
situations, must be owing to the same general law of vegetation. The
trees of Tierra del Fuego during no part of the year entirely shed
their leaves.

[4] Described from my specimens and notes by the Rev. J. M. Berkeley,
in the Linnean Transactions (vol. xix. p. 37), under the name of
Cyttaria Darwinii; the Chilean species is the C. Berteroii.  This genus
is allied to Bulgaria.

[5] I believe I must except one alpine Haltica, and a single specimen
of a Melasoma.  Mr. Waterhouse informs me, that of the Harpalidae there
are eight or nine species--the forms of the greater number being very
peculiar; of Heteromera, four or five species; of Rhyncophora, six or
seven; and of the following families one species in each:
Staphylinidae, Elateridae, Cebrionidae, Melolonthidae.  The species in
the other orders are even fewer.  In all the orders, the scarcity of
the individuals is even more remarkable than that of the species.  Most
of the Coleoptera have been carefully described by Mr. Waterhouse in
the Annals of Nat. Hist.

[6] Its geographical range is remarkably wide; it is found from the
extreme southern islets near Cape Horn, as far north on the eastern
coast (according to information given me by Mr. Stokes) as lat. 43
degs.,--but on the western coast, as Dr. Hooker tells me, it extends to
the R. San Francisco in California, and perhaps even to Kamtschatka. We
thus have an immense range in latitude; and as Cook, who must have been
well acquainted with the species, found it at Kerguelen Land, no less
than 140 degs. in longitude.

[7] Voyages of the Adventure and Beagle, vol. i. p. 363.--It appears
that sea-weed grows extremely quick.--Mr. Stephenson found (Wilson's
Voyage round Scotland, vol. ii. p. 228) that a rock uncovered only at
spring-tides, which had been chiselled smooth in November, on the
following May, that is, within six months afterwards, was thickly
covered with Fucus digitatus two feet, and F. esculentus six feet, in
length.

[8] With regard to Tierra del Fuego, the results are deduced from the
observations of Capt. King (Geographical Journal, 1830), and those
taken on board the Beagle.  For the Falkland Islands, I am indebted to
Capt. Sulivan for the mean of the mean temperature (reduced from
careful observations at midnight, 8 A.M., noon, and 8 P.M.) of the
three hottest months, viz., December, January, and February.  The
temperature of Dublin is taken from Barton.

[9] Agueros, Descrip. Hist. de la Prov. de Chiloe, 1791, p. 94.

[10] See the German Translation of this Journal; and for the other
facts, Mr. Brown's Appendix to Flinders's Voyage.


[11] On the Cordillera of central Chile, I believe the snow-line varies
exceedingly in height in different summers. I was assured that during
one very dry and long summer, all the snow disappeared from Aconcagua,
although it attains the prodigious height of 23,000 feet.  It is
probable that much of the snow at these great heights is evaporated
rather than thawed.

[12] Miers's Chile, vol. i. p. 415. It is said that the sugar-cane grew
at Ingenio, lat. 32 to 33 degs., but not in sufficient quantity to make
the manufacture profitable.  In the valley of Quillota, south of
Ingenio, I saw some large date palm trees.

[13] Bulkeley's and Cummin's Faithful Narrative of the Loss of the
Wager.  The earthquake happened August 25, 1741.

[14] Agueros, Desc. Hist. de Chiloe, p. 227.

[15] Geological Transactions, vol. vi. p. 415.

[16] I have given details (the first, I believe, published) on this
subject in the first edition, and in the Appendix to it. I have there
shown that the apparent exceptions to the absence of erratic boulders
in certain countries, are due to erroneous observations; several
statements there given I have since found confirmed by various authors.

[17] Geographical Journal, 1830, pp. 65, 66.

[18] Richardson's Append. to Back's Exped., and Humboldt's Fragm.
Asiat., tom. ii. p. 386.

[19] Messrs. Dease and Simpson, in Geograph. Journ., vol. viii. pp. 218
and 220.

[20] Cuvier (Ossemens Fossiles, tom. i. p. 151), from Billing's Voyage.

[21] In the former edition and Appendix, I have given some facts on the
transportal of erratic boulders and icebergs in the Atlantic Ocean.
This subject has lately been treated excellently by Mr. Hayes, in the
Boston Journal (vol. iv. p. 426).  The author does not appear aware of
a case published by me (Geographical Journal, vol. ix. p. 528) of a
gigantic boulder embedded in an iceberg in the Antarctic Ocean, almost
certainly one hundred miles distant from any land, and perhaps much
more distant.  In the Appendix I have discussed at length the
probability (at that time hardly thought of) of icebergs, when
stranded, grooving and polishing rocks, like glaciers.  This is now a
very commonly received opinion; and I cannot still avoid the suspicion
that it is applicable even to such cases as that of the Jura.  Dr.
Richardson has assured me that the icebergs off North America push
before them pebbles and sand, and leave the submarine rocky flats quite
bare; it is hardly possible to doubt that such ledges must be polished
and scored in the direction of the set of the prevailing currents.
Since writing that Appendix, I have seen in North Wales (London Phil.
Mag., vol. xxi. p. 180) the adjoining action of glaciers and floating
icebergs.



CHAPTER XII

CENTRAL CHILE

Valparaiso--Excursion to the Foot of the Andes--Structure of the
Land--Ascend the Bell of Quillota--Shattered Masses of
Greenstone--Immense Valleys--Mines--State of
Miners--Santiago--Hot-baths of
Cauquenes--Gold-mines--Grinding-mills--Perforated Stones--Habits of the
Puma--El Turco and Tapacolo--Humming-birds.


JULY 23rd.--The Beagle anchored late at night in the bay of Valparaiso,
the chief seaport of Chile.  When morning came, everything appeared
delightful.  After Tierra del Fuego, the climate felt quite
delicious--the atmosphere so dry, and the heavens so clear and blue
with the sun shining brightly, that all nature seemed sparkling with
life.  The view from the anchorage is very pretty.  The town is built
at the very foot of a range of hills, about 1600 feet high, and rather
steep.  From its position, it consists of one long, straggling street,
which runs parallel to the beach, and wherever a ravine comes down, the
houses are piled up on each side of it.  The rounded hills, being only
partially protected by a very scanty vegetation, are worn into
numberless little gullies, which expose a singularly bright red soil.
From this cause, and from the low whitewashed houses with tile roofs,
the view reminded me of St. Cruz in Teneriffe.  In a north-westerly
direction there are some fine glimpses of the Andes: but these
mountains appear much grander when viewed from the neighbouring hills:
the great distance at which they are situated can then more readily be
perceived.  The volcano of Aconcagua is particularly magnificent.  This
huge and irregularly conical mass has an elevation greater than that of
Chimborazo; for, from measurements made by the officers in the Beagle,
its height is no less than 23,000 feet.  The Cordillera, however,
viewed from this point, owe the greater part of their beauty to the
atmosphere through which they are seen.  When the sun was setting in
the Pacific, it was admirable to watch how clearly their rugged
outlines could be distinguished, yet how varied and how delicate were
the shades of their colour.

I had the good fortune to find living here Mr. Richard Corfield, an old
schoolfellow and friend, to whose hospitality and kindness I was
greatly indebted, in having afforded me a most pleasant residence
during the Beagle's stay in Chile. The immediate neighbourhood of
Valparaiso is not very productive to the naturalist.  During the long
summer the wind blows steadily from the southward, and a little off
shore, so that rain never falls; during the three winter months,
however, it is sufficiently abundant.  The vegetation in consequence is
very scanty: except in some deep valleys, there are no trees, and only
a little grass and a few low bushes are scattered over the less steep
parts of the hills.  When we reflect, that at the distance of 350 miles
to the south, this side of the Andes is completely hidden by one
impenetrable forest, the contrast is very remarkable.  I took several
long walks while collecting objects of natural history.  The country is
pleasant for exercise.  There are many very beautiful flowers; and, as
in most other dry climates, the plants and shrubs possess strong and
peculiar odours--even one's clothes by brushing through them became
scented.  I did not cease from wonder at finding each succeeding day as
fine as the foregoing. What a difference does climate make in the
enjoyment of life!  How opposite are the sensations when viewing black
mountains half enveloped in clouds, and seeing another range through
the light blue haze of a fine day!  The one for a time may be very
sublime; the other is all gaiety and happy life.

August 14th.--I  set out on a riding excursion, for the purpose of
geologizing the basal parts of the Andes, which alone at this time of
the year are not shut up by the winter snow.  Our first day's ride was
northward along the sea-coast. After dark we reached the Hacienda of
Quintero, the estate which formerly belonged to Lord Cochrane.  My
object in coming here was to see the great beds of shells, which stand
some yards above the level of the sea, and are burnt for lime.  The
proofs of the elevation of this whole line of coast are unequivocal: at
the height of a few hundred feet old-looking shells are numerous, and I
found some at 1300 feet.  These shells either lie loose on the surface,
or are embedded in a reddish-black vegetable mould.  I was much
surprised to find under the microscope that this vegetable mould is
really marine mud, full of minute particles of organic bodies.

15th.--We returned towards the valley of Quillota.  The country was
exceedingly pleasant; just such as poets would call pastoral: green
open lawns, separated by small valleys with rivulets, and the cottages,
we may suppose of the shepherds scattered on the hill-sides.  We were
obliged to cross the ridge of the Chilicauquen.  At its base there were
many fine evergreen forest-trees, but these flourished only in the
ravines, where there was running water.  Any person who had seen only
the country near Valparaiso, would never have imagined that there had
been such picturesque spots in Chile. As soon as we reached the brow of
the Sierra, the valley of Quillota was immediately under our feet.  The
prospect was one of remarkable artificial luxuriance.  The valley is
very broad and quite flat, and is thus easily irrigated in all parts.
The little square gardens are crowded with orange and olive trees, and
every sort of vegetable.  On each side huge bare mountains rise, and
this from the contrast renders the patchwork valley the more pleasing.
Whoever called "Valparaiso" the "Valley of Paradise," must have been
thinking of Quillota.  We crossed over to the Hacienda de San Isidro,
situated at the very foot of the Bell Mountain.

Chile, as may be seen in the maps, is a narrow strip of land between
the Cordillera and the Pacific; and this strip is itself traversed by
several mountain-lines, which in this part run parallel to the great
range.  Between these outer lines and the main Cordillera, a succession
of level basins, generally opening into each other by narrow passages,
extend far to the southward: in these, the principal towns are
situated, as San Felipe, Santiago, San Fernando.  These basins or
plains, together with the transverse flat valleys (like that of
Quillota) which connect them with the coast, I have no doubt are the
bottoms of ancient inlets and deep bays, such as at the present day
intersect every part of Tierra del Fuego and the western coast.  Chile
must formerly have resembled the latter country in the configuration of
its land and water. The resemblance was occasionally shown strikingly
when a level fog-bank covered, as with a mantle, all the lower parts of
the country: the white vapour curling into the ravines, beautifully
represented little coves and bays; and here and there a solitary
hillock peeping up, showed that it had formerly stood there as an
islet.  The contrast of these flat valleys and basins with the
irregular mountains, gave the scenery a character which to me was new
and very interesting.

From the natural slope to seaward of these plains, they are very easily
irrigated, and in consequence singularly fertile.  Without this process
the land would produce scarcely anything, for during the whole summer
the sky is cloudless. The mountains and hills are dotted over with
bushes and low trees, and excepting these the vegetation is very
scanty. Each landowner in the valley possesses a certain portion of
hill-country, where his half-wild cattle, in considerable numbers,
manage to find sufficient pasture.  Once every year there is a grand
"rodeo," when all the cattle are driven down, counted, and marked, and
a certain number separated to be fattened in the irrigated fields.
Wheat is extensively cultivated, and a good deal of Indian corn: a kind
of bean is, however, the staple article of food for the common
labourers. The orchards produce an overflowing abundance of peaches
figs, and grapes.  With all these advantages, the inhabitants of the
country ought to be much more prosperous than they are.

16th.--The mayor-domo of the Hacienda was good enough to give me a
guide and fresh horses; and in the morning we set out to ascend the
Campana, or Bell Mountain, which is 6400 feet high.  The paths were
very bad, but both the geology and scenery amply repaid the trouble. We
reached by the evening, a spring called the Agua del Guanaco, which is
situated at a great height.  This must be an old name, for it is very
many years since a guanaco drank its waters. During the ascent I
noticed that nothing but bushes grew on the northern slope, whilst on
the southern slope there was a bamboo about fifteen feet high.  In a
few places there were palms, and I was surprised to see one at an
elevation of at least 4500 feet.  These palms are, for their family,
ugly trees. Their stem is very large, and of a curious form, being
thicker in the middle than at the base or top.  They are excessively
numerous in some parts of Chile, and valuable on account of a sort of
treacle made from the sap.  On one estate near Petorca they tried to
count them, but failed, after having numbered several hundred thousand.
Every year in the early spring, in August, very many are cut down, and
when the trunk is lying on the ground, the crown of leaves is lopped
off.  The sap then immediately begins to flow from the upper end, and
continues so doing for some months: it is, however, necessary that a
thin slice should be shaved off from that end every morning, so as to
expose a fresh surface.  A good tree will give ninety gallons, and all
this must have been contained in the vessels of the apparently dry
trunk. It is said that the sap flows much more quickly on those days
when the sun is powerful; and likewise, that it is absolutely necessary
to take care, in cutting down the tree, that it should fall with its
head upwards on the side of the hill; for if it falls down the slope,
scarcely any sap will flow; although in that case one would have
thought that the action would have been aided, instead of checked, by
the force of gravity.  The sap is concentrated by boiling, and is then
called treacle, which it very much resembles in taste.

We unsaddled our horses near the spring, and prepared to pass the
night.  The evening was fine, and the atmosphere so clear, that the
masts of the vessels at anchor in the bay of Valparaiso, although no
less than twenty-six geographical miles distant, could be distinguished
clearly as little black streaks.  A ship doubling the point under sail,
appeared as a bright white speck.  Anson expresses much surprise, in
his voyage, at the distance at which his vessels were discovered from
the coast; but he did not sufficiently allow for the height of the
land, and the great transparency of the air.

The setting of the sun was glorious; the valleys being black whilst the
snowy peaks of the Andes yet retained a ruby tint.  When it was dark,
we made a fire beneath a little arbour of bamboos, fried our charqui
(or dried slips of beef), took our mate, and were quite comfortable.
There is an inexpressible charm in thus living in the open air.  The
evening was calm and still;--the shrill noise of the mountain bizcacha,
and the faint cry of a goatsucker, were occasionally to be heard.
Besides these, few birds, or even insects, frequent these dry, parched
mountains.

August 17th.--In the morning we climbed up the rough mass of greenstone
which crowns the summit.  This rock, as frequently happens, was much
shattered and broken into huge angular fragments.  I observed, however,
one remarkable circumstance, namely, that many of the surfaces
presented every degree of freshness some appearing as if broken the day
before, whilst on others lichens had either just become, or had long
grown, attached.  I so fully believed that this was owing to the
frequent earthquakes, that I felt inclined to hurry from below each
loose pile.  As one might very easily be deceived in a fact of this
kind, I doubted its accuracy, until ascending Mount Wellington, in Van
Diemen's Land, where earthquakes do not occur; and there I saw the
summit of the mountain similarly composed and similarly shattered, but
all the blocks appeared as if they had been hurled into their present
position thousands of years ago.

We spent the day on the summit, and I never enjoyed one more
thoroughly.  Chile, bounded by the Andes and the Pacific, was seen as
in a map.  The pleasure from the scenery, in itself beautiful, was
heightened by the many reflections which arose from the mere view of
the Campana range with its lesser parallel ones, and of the broad
valley of Quillota directly intersecting them.  Who can avoid wondering
at the force which has upheaved these mountains, and even more so at
the countless ages which it must have required to have broken through,
removed, and levelled whole masses of them? It is well in this case to
call to mind the vast shingle and sedimentary beds of Patagonia, which,
if heaped on the Cordillera, would increase its height by so many
thousand feet. When in that country, I wondered how any mountain-chain
could have supplied such masses, and not have been utterly obliterated.
We must not now reverse the wonder, and doubt whether all-powerful time
can grind down mountains--even the gigantic Cordillera--into-gravel and
mud.

The appearance of the Andes was different from that which I had
expected.  The lower line of the snow was of course horizontal, and to
this line the even summits of the range seemed quite parallel.  Only at
long intervals, a group of points or a single cone showed where a
volcano had existed, or does now exist.  Hence the range resembled a
great solid wall, surmounted here and there by a tower, and making a
most perfect barrier to the country.

Almost every part of the hill had been drilled by attempts to open
gold-mines: the rage for mining has left scarcely a spot in Chile
unexamined.  I spent the evening as before, talking round the fire with
my two companions.  The Guasos of Chile, who correspond to the Gauchos
of the Pampas, are, however, a very different set of beings.  Chile is
the more civilized of the two countries, and the inhabitants, in
consequence, have lost much individual character.  Gradations in rank
are much more strongly marked: the Guaso does not by any means consider
every man his equal; and I was quite surprised to find that my
companions did not like to eat at the same time with myself.  This
feeling of inequality is a necessary consequence of the existence of an
aristocracy of wealth.  It is said that some few of the greater
landowners possess from five to ten thousand pounds sterling per annum:
an inequality of riches which I believe is not met with in any of the
cattle-breeding countries eastward of the Andes. A traveller does not
here meet that unbounded hospitality which refuses all payment, but yet
is so kindly offered that no scruples can be raised in accepting it.
Almost every house in Chile will receive you for the night, but a
trifle is expected to be given in the morning; even a rich man will
accept two or three shillings.  The Gaucho, although he may be a
cutthroat, is a gentleman; the Guaso is in few respects better, but at
the same time a vulgar, ordinary fellow.  The two men, although
employed much in the same manner, are different in their habits and
attire; and the peculiarities of each are universal in their respective
countries.  The Gaucho seems part of his horse, and scorns to exert
himself except when on his back: the Guaso may be hired to work as a
labourer in the fields.  The former lives entirely on animal food; the
latter almost wholly on vegetable.  We do not here see the white boots,
the broad drawers and scarlet chilipa; the picturesque costume of the
Pampas.  Here, common trousers are protected by black and green worsted
leggings.  The poncho, however, is common to both.  The chief pride of
the Guaso lies in his spurs, which are absurdly large.  I measured one
which was six inches in the _diameter_  of the rowel, and the rowel
itself contained upwards of thirty points.  The stirrups are on the
same scale, each consisting of a square, carved block of wood, hollowed
out, yet weighing three or four pounds.  The Guaso is perhaps more
expert with the lazo than the Gaucho; but, from the nature of the
country, he does not know the use of the bolas.

August 18th.--We descended the mountain, and passed some beautiful
little spots, with rivulets and fine trees. Having slept at the same
hacienda as before, we rode during the two succeeding days up the
valley, and passed through Quillota, which is more like a collection of
nursery-gardens than a town.  The orchards were beautiful, presenting
one mass of peach-blossoms.  I saw, also, in one or two places the
date-palm; it is a most stately tree; and I should think a group of
them in their native Asiatic or African deserts must be superb.  We
passed likewise San Felipe, a pretty straggling town like Quillota. The
valley in this part expands into one of those great bays or plains,
reaching to the foot of the Cordillera, which have been mentioned as
forming so curious a part of the scenery of Chile.  In the evening we
reached the mines of Jajuel, situated in a ravine at the flank of the
great chain.  I stayed here five days.  My host the superintendent of
the mine, was a shrewd but rather ignorant Cornish miner.  He had
married a Spanish woman, and did not mean to return home; but his
admiration for the mines of Cornwall remained unbounded.  Amongst many
other questions, he asked me, "Now that George Rex is dead, how many
more of the family of Rexes are yet alive?" This Rex certainly must be
a relation of the great author Finis, who wrote all books!

These mines are of copper, and the ore is all shipped to Swansea, to be
smelted.  Hence the mines have an aspect singularly quiet, as compared
to those in England: here no smoke, furnaces, or great steam-engines,
disturb the solitude of the surrounding mountains.

The Chilian government, or rather the old Spanish law, encourages by
every method the searching for mines.  The discoverer may work a mine
on any ground, by paying five shillings; and before paying this he may
try, even in the garden of another man, for twenty days.

It is now well known that the Chilian method of mining is the cheapest.
My host says that the two principal improvements introduced by
foreigners have been, first, reducing by previous roasting the copper
pyrites--which, being the common ore in Cornwall, the English miners
were astounded on their arrival to find thrown away as useless:
secondly, stamping and washing the scoriae from the old furnaces--by
which process particles of metal are recovered in abundance.  I have
actually seen mules carrying to the coast, for transportation to
England, a cargo of such cinders. But the first case is much the most
curious.  The Chilian miners were so convinced that copper pyrites
contained not a particle of copper, that they laughed at the Englishmen
for their ignorance, who laughed in turn, and bought their richest
veins for a few dollars.  It is very odd that, in a country where
mining had been extensively carried on for many years, so simple a
process as gently roasting the ore to expel the sulphur previous to
smelting it, had never been discovered. A few improvements have
likewise been introduced in some of the simple machinery; but even to
the present day, water is removed from some mines by men carrying it up
the shaft in leathern bags!

The labouring men work very hard.  They have little time allowed for
their meals, and during summer and winter they begin when it is light,
and leave off at dark.  They are paid one pound sterling a month, and
their food is given them: this for breakfast consists of sixteen figs
and two small loaves of bread; for dinner, boiled beans; for supper,
broken roasted wheat grain.  They scarcely ever taste meat; as, with
the twelve pounds per annum, they have to clothe themselves, and
support their families.  The miners who work in the mine itself have
twenty-five shillings per month, and are allowed a little charqui.  But
these men come down from their bleak habitations only once in every
fortnight or three weeks.

During my stay here I thoroughly enjoyed scrambling about these huge
mountains.  The geology, as might have been expected, was very
interesting.  The shattered and baked rocks, traversed by innumerable
dykes of greenstone, showed what commotions had formerly taken place.
The scenery was much the same as that near the Bell of Quillota--dry
barren mountains, dotted at intervals by bushes with a scanty foliage.
The cactuses, or rather opuntias were here very numerous.  I measured
one of a spherical figure, which, including the spines, was six feet
and four inches in circumference.  The height of the common
cylindrical, branching kind, is from twelve to fifteen feet, and the
girth (with spines) of the branches between three and four feet.

A heavy fall of snow on the mountains prevented me during the last two
days, from making some interesting excursions.  I attempted to reach a
lake which the inhabitants, from some unaccountable reason, believe to
be an arm of the sea.  During a very dry season, it was proposed to
attempt cutting a channel from it for the sake of the water, but the
padre, after a consultation, declared it was too dangerous, as all
Chile would be inundated, if, as generally supposed, the lake was
connected with the Pacific.  We ascended to a great height, but
becoming involved in the snow-drifts failed in reaching this wonderful
lake, and had some difficulty in returning.  I thought we should have
lost our horses; for there was no means of guessing how deep the drifts
were, and the animals, when led, could only move by jumping.  The black
sky showed that a fresh snow-storm was gathering, and we therefore were
not a little glad when we escaped.  By the time we reached the base the
storm commenced, and it was lucky for us that this did not happen three
hours earlier in the day.

August 26th.--We left Jajuel and again crossed the basin of San Felipe.
The day was truly Chilian: glaringly bright, and the atmosphere quite
clear.  The thick and uniform covering of newly fallen snow rendered
the view of the volcano of Aconcagua and the main chain quite glorious.
We were now on the road to Santiago, the capital of Chile.  We crossed
the Cerro del Talguen, and slept at a little rancho. The host, talking
about the state of Chile as compared to other countries, was very
humble: "Some see with two eyes, and some with one, but for my part I
do not think that Chile sees with any."

August 27th.--After crossing many low hills we descended into the small
land-locked plain of Guitron.  In the basins, such as this one, which
are elevated from one thousand to two thousand feet above the sea, two
species of acacia, which are stunted in their forms, and stand wide
apart from each other, grow in large numbers.  These trees are never
found near the sea-coast; and this gives another characteristic feature
to the scenery of these basins.  We crossed a low ridge which separates
Guitron from the great plain on which Santiago stands.  The view was
here pre-eminently striking: the dead level surface, covered in parts
by woods of acacia, and with the city in the distance, abutting
horizontally against the base of the Andes, whose snowy peaks were
bright with the evening sun.  At the first glance of this view, it was
quite evident that the plain represented the extent of a former inland
sea.  As soon as we gained the level road we pushed our horses into a
gallop, and reached the city before it was dark.

I stayed a week in Santiago, and enjoyed myself very much.  In the
morning I rode to various places on the plain, and in the evening dined
with several of the English merchants, whose hospitality at this place
is well known.  A never-failing source of pleasure was to ascend the
little hillock of rock (St. Lucia) which projects in the middle of the
city.  The scenery certainly is most striking, and, as I have said,
very peculiar.  I am informed that this same character is common to the
cities on the great Mexican platform.  Of the town I have nothing to
say in detail: it is not so fine or so large as Buenos Ayres, but is
built after the same model.  I arrived here by a circuit to the north;
so I resolved to return to Valparaiso by a rather longer excursion to
the south of the direct road.

September 5th.--By the middle of the day we arrived at one of the
suspension bridges, made of hide, which cross the Maypu, a large
turbulent river a few leagues southward of Santiago.  These bridges are
very poor affairs.  The road, following the curvature of the suspending
ropes, is made of bundles of sticks placed close together.  It was full
of holes, and oscillated rather fearfully, even with the weight of a
man leading his horse.  In the evening we reached a comfortable
farm-house, where there were several very pretty senoritas.  They were
much horrified at my having entered one of their churches out of mere
curiosity.  They asked me, "Why do you not become a Christian--for our
religion is certain?" I assured them I was a sort of Christian; but
they would not hear of it--appealing to my own words, "Do not your
padres, your very bishops, marry?" The absurdity of a bishop having a
wife particularly struck them: they scarcely knew whether to be most
amused or horror-struck at such an enormity.

6th.--We proceeded due south, and slept at Rancagua. The road passed
over the level but narrow plain, bounded on one side by lofty hills,
and on the other by the Cordillera. The next day we turned up the
valley of the Rio Cachapual, in which the hot-baths of Cauquenes, long
celebrated for their medicinal properties, are situated.  The
suspension bridges, in the less frequented parts, are generally taken
down during the winter when the rivers are low.  Such was the case in
this valley, and we were therefore obliged to cross the stream on
horseback.  This is rather disagreeable, for the foaming water, though
not deep, rushes so quickly over the bed of large rounded stones, that
one's head becomes quite confused, and it is difficult even to perceive
whether the horse is moving onward or standing still.  In summer, when
the snow melts, the torrents are quite impassable; their strength and
fury are then extremely great, as might be plainly seen by the marks
which they had left.  We reached the baths in the evening, and stayed
there five days, being confined the two last by heavy rain.  The
buildings consist of a square of miserable little hovels, each with a
single table and bench.  They are situated in a narrow deep valley just
without the central Cordillera.  It is a quiet, solitary spot, with a
good deal of wild beauty.

The mineral springs of Cauquenes burst forth on a line of dislocation,
crossing a mass of stratified rock, the whole of which betrays the
action of heat.  A considerable quantity of gas is continually escaping
from the same orifices with the water.  Though the springs are only a
few yards apart, they have very different temperature; and this appears
to be the result of an unequal mixture of cold water: for those with
the lowest temperature have scarcely any mineral taste. After the great
earthquake of 1822 the springs ceased, and the water did not return for
nearly a year.  They were also much affected by the earthquake of 1835;
the temperature being suddenly changed from 118 to 92 degs. [1] It
seems probable that mineral waters rising deep from the bowels of the
earth, would always be more deranged by subterranean disturbances than
those nearer the surface.  The man who had charge of the baths assured
me that in summer the water is hotter and more plentiful than in
winter.  The former circumstance I should have expected, from the less
mixture, during the dry season, of cold water; but the latter statement
appears very strange and contradictory.  The periodical increase during
the summer, when rain never falls, can, I think, only be accounted for
by the melting of the snow: yet the mountains which are covered by snow
during that season, are three or four leagues distant from the springs.
I have no reason to doubt the accuracy of my informer, who, having
lived on the spot for several years, ought to be well acquainted with
the circumstance,--which, if true, certainly is very curious: for we
must suppose that the snow-water, being conducted through porous strata
to the regions of heat, is again thrown up to the surface by the line
of dislocated and injected rocks at Cauquenes; and the regularity of
the phenomenon would seem to indicate that in this district heated rock
occurred at a depth not very great.

One day I rode up the valley to the farthest inhabited spot.  Shortly
above that point, the Cachapual divides into two deep tremendous
ravines, which penetrate directly into the great range.  I scrambled up
a peaked mountain, probably more than six thousand feet high.  Here, as
indeed everywhere else, scenes of the highest interest presented
themselves.  It was by one of these ravines, that Pincheira entered
Chile and ravaged the neighbouring country.  This is the same man whose
attack on an estancia at the Rio Negro I have described.  He was a
renegade half-caste Spaniard, who collected a great body of Indians
together and established himself by a stream in the Pampas, which place
none of the forces sent after him could ever discover.  From this point
he used to sally forth, and crossing the Cordillera by passes hitherto
unattempted, he ravaged the farm-houses and drove the cattle to his
secret rendezvous.  Pincheira was a capital horseman, and he made all
around him equally good, for he invariably shot any one who hesitated
to follow him.  It was against this man, and other wandering Indian
tribes, that Rosas waged the war of extermination.

September 13th.--We left the baths of Cauquenes, and, rejoining the
main road, slept at the Rio Clara.  From this place we rode to the town
of San Fernando.  Before arriving there, the last land-locked basin had
expanded into a great plain, which extended so far to the south, that
the snowy summits of the more distant Andes were seen as if above the
horizon of the sea.  San Fernando is forty leagues from Santiago; and
it was my farthest point southward; for we here turned at right angles
towards the coast.  We slept at the gold-mines of Yaquil, which are
worked by Mr. Nixon, an American gentleman, to whose kindness I was
much indebted during the four days I stayed at his house.  The next
morning we rode to the mines, which are situated at the distance of
some leagues, near the summit of a lofty hill.  On the way we had a
glimpse of the lake Tagua-tagua, celebrated for its floating islands,
which have been described by M. Gay. [2] They are composed of the
stalks of various dead plants intertwined together, and on the surface
of which other living ones take root.  Their form is generally
circular, and their thickness from four to six feet, of which the
greater part is immersed in the water.  As the wind blows, they pass
from one side of the lake to the other, and often carry cattle and
horses as passengers.

When we arrived at the mine, I was struck by the pale appearance of
many of the men, and inquired from Mr. Nixon respecting their
condition.  The mine is 450 feet deep, and each man brings up about 200
pounds weight of stone. With this load they have to climb up the
alternate notches cut in the trunks of trees, placed in a zigzag line
up the shaft. Even beardless young men, eighteen and twenty years old,
with little muscular development of their bodies (they are quite naked
excepting drawers) ascend with this great load from nearly the same
depth.  A strong man, who is not accustomed to this labour, perspires
most profusely, with merely carrying up his own body.  With this very
severe labour, they live entirely on boiled beans and bread.  They
would prefer having bread alone; but their masters, finding that they
cannot work so hard upon this, treat them like horses, and make them
eat the beans.  Their pay is here rather more than at the mines of
Jajuel, being from 24 to 28 shillings per month.  They leave the mine
only once in three weeks; when they stay with their families for two
days.  One of the rules of this mine sounds very harsh, but answers
pretty well for the master.  The only method of stealing gold is to
secrete pieces of the ore, and take them out as occasion may offer.
Whenever the major-domo finds a lump thus hidden, its full value is
stopped out of the wages of all the men; who thus, without they all
combine, are obliged to keep watch over each other.

When the ore is brought to the mill, it is ground into an impalpable
powder; the process of washing removes all the lighter particles, and
amalgamation finally secures the gold-dust.  The washing, when
described, sounds a very simple process; but it is beautiful to see how
the exact adaptation of the current of water to the specific gravity of
the gold, so easily separates the powdered matrix from the metal.  The
mud which passes from the mills is collected into pools, where it
subsides, and every now and then is cleared out, and thrown into a
common heap.  A great deal of chemical action then commences, salts of
various kinds effloresce on the surface, and the mass becomes hard.
After having been left for a year or two, and then rewashed, it yields
gold; and this process may be repeated even six or seven times; but the
gold each time becomes less in quantity, and the intervals required (as
the inhabitants say, to generate the metal) are longer.  There can be
no doubt that the chemical action, already mentioned, each time
liberates fresh gold from some combination.  The discovery of a method
to effect this before the first grinding would without doubt raise the
value of gold-ores many fold.

It is curious to find how the minute particles of gold, being scattered
about and not corroding, at last accumulate in some quantity.  A short
time since a few miners, being out of work, obtained permission to
scrape the ground round the house and mills; they washed the earth thus
got together, and so procured thirty dollars' worth of gold.  This is
an exact counterpart of what takes place in nature.  Mountains suffer
degradation and wear away, and with them the metallic veins which they
contain.  The hardest rock is worn into impalpable mud, the ordinary
metals oxidate, and both are removed; but gold, platina, and a few
others are nearly indestructible, and from their weight, sinking to the
bottom, are left behind. After whole mountains have passed through this
grinding mill, and have been washed by the hand of nature, the residue
becomes metalliferous, and man finds it worth his while to complete the
task of separation.

Bad as the above treatment of the miners appears, it is gladly accepted
of by them; for the condition of the labouring agriculturists is much
worse.  Their wages are lower, and they live almost exclusively on
beans.  This poverty must be chiefly owing to the feudal-like system on
which the land is tilled: the landowner gives a small plot of ground to
the labourer for building on and cultivating, and in return has his
services (or those of a proxy) for every day of his life, without any
wages.  Until a father has a grown-up son, who can by his labour pay
the rent, there is no one, except on occasional days, to take care of
his own patch of ground. Hence extreme poverty is very common among the
labouring classes in this country.

There are some old Indian ruins in this neighbourhood, and I was shown
one of the perforated stones, which Molina mentions as being found in
many places in considerable numbers.  They are of a circular flattened
form, from five to six inches in diameter, with a hole passing quite
through the centre.  It has generally been supposed that they were used
as heads to clubs, although their form does not appear at all well
adapted for that purpose.  Burchell [3] states that some of the tribes
in Southern Africa dig up roots by the aid of a stick pointed at one
end, the force and weight of which are increased by a round stone with
a hole in it, into which the other end is firmly wedged.  It appears
probable that the Indians of Chile formerly used some such rude
agricultural instrument.

One day, a German collector in natural history, of the name of Renous,
called, and nearly at the same time an old Spanish lawyer.  I was
amused at being told the conversation which took place between them.
Renous speaks Spanish so well, that the old lawyer mistook him for a
Chilian.  Renous alluding to me, asked him what he thought of the King
of England sending out a collector to their country, to pick up lizards
and beetles, and to break stones?  The old gentleman thought seriously
for some time, and then said, "It is not well,--_hay un gato encerrado
aqui_ (there is a cat shut up here).  No man is so rich as to send out
people to pick up such rubbish.  I do not like it: if one of us were to
go and do such things in England, do not you think the King of England
would very soon send us out of his country?" And this old gentleman,
from his profession, belongs to the better informed and more
intelligent classes!  Renous himself, two or three years before, left
in a house at San Fernando some caterpillars, under charge of a girl to
feed, that they might turn into butterflies.  This was rumoured through
the town, and at last the padres and governor consulted together, and
agreed it must be some heresy.  Accordingly, when Renous returned, he
was arrested.

September 19th.--We left Yaquil, and followed the flat valley, formed
like that of Quillota, in which the Rio Tinderidica flows.  Even at
these few miles south of Santiago the climate is much damper; in
consequence there are fine tracts of pasturage, which are not
irrigated. (20th.) We followed this valley till it expanded into a
great plain, which reaches from the sea to the mountains west of
Rancagua. We shortly lost all trees and even bushes; so that the
inhabitants are nearly as badly off for firewood as those in the
Pampas.  Never having heard of these plains, I was much surprised at
meeting with such scenery in Chile.  The plains belong to more than one
series of different elevations, and they are traversed by broad
flat-bottomed valleys; both of which circumstances, as in Patagonia,
bespeak the action of the sea on gently rising land.  In the steep
cliffs bordering these valleys, there are some large caves, which no
doubt were originally formed by the waves: one of these is celebrated
under the name of Cueva del Obispo; having formerly been consecrated.
During the day I felt very unwell, and from that time till the end of
October did not recover.

September 22nd.--We continued to pass over green plains without a tree.
The next day we arrived at a house near Navedad, on the sea-coast,
where a rich Haciendero gave us lodgings.  I stayed here the two
ensuing days, and although very unwell, managed to collect from the
tertiary formation some marine shells.

24th.--Our course was now directed towards Valparaiso, which with great
difficulty I reached on the 27th, and was there confined to my bed till
the end of October.  During this time I was an inmate in Mr. Corfield's
house, whose kindness to me I do not know how to express.


I will here add a few observations on some of the animals and birds of
Chile.  The Puma, or South American Lion, is not uncommon.  This animal
has a wide geographical range; being found from the equatorial forests,
throughout the deserts of Patagonia as far south as the damp and cold
latitudes (53 to 54 degs.) of Tierra del Fuego.  I have seen its
footsteps in the Cordillera of central Chile, at an elevation of at
least 10,000 feet.  In La Plata the puma preys chiefly on deer,
ostriches, bizcacha, and other small quadrupeds; it there seldom
attacks cattle or horses, and most rarely man.  In Chile, however, it
destroys many young horses and cattle, owing probably to the scarcity
of other quadrupeds: I heard, likewise, of two men and a woman who had
been thus killed. It is asserted that the puma always kills its prey by
springing on the shoulders, and then drawing back the head with one of
its paws, until the vertebrae break: I have seen in Patagonia the
skeletons of guanacos, with their necks thus dislocated.

The puma, after eating its fill, covers the carcass with many large
bushes, and lies down to watch it.  This habit is often the cause of
its being discovered; for the condors wheeling in the air every now and
then descend to partake of the feast, and being angrily driven away,
rise all together on the wing.  The Chileno Guaso then knows there is a
lion watching his prey--the word is given--and men and dogs hurry to
the chase.  Sir F. Head says that a Gaucho in the pampas, upon merely
seeing some condors wheeling in the air, cried "A lion!" I could never
myself meet with any one who pretended to such powers of
discrimination.  It is asserted that, if a puma has once been betrayed
by thus watching the carcass, and has then been hunted, it never
resumes this habit; but that, having gorged itself, it wanders far
away. The puma is easily killed.  In an open country, it is first
entangled with the bolas, then lazoed, and dragged along the ground
till rendered insensible.  At Tandeel (south of the plata), I was told
that within three months one hundred were thus destroyed.  In Chile
they are generally driven up bushes or trees, and are then either shot,
or baited to death by dogs.  The dogs employed in this chase belong to
a particular breed, called Leoneros: they are weak, slight animals,
like long-legged terriers, but are born with a particular instinct for
this sport.  The puma is described as being very crafty: when pursued,
it often returns on its former track, and then suddenly making a spring
on one side, waits there till the dogs have passed by.  It is a very
silent animal, uttering no cry even when wounded, and only rarely
during the breeding season.

Of birds, two species of the genus Pteroptochos (megapodius and
albicollis of Kittlitz) are perhaps the most conspicuous. The former,
called by the Chilenos "el Turco," is as large as a fieldfare, to which
bird it has some alliance; but its legs are much longer, tail shorter,
and beak stronger: its colour is a reddish brown.  The Turco is not
uncommon. It lives on the ground, sheltered among the thickets which
are scattered over the dry and sterile hills.  With its tail erect, and
stilt-like legs, it may be seen every now and then popping from one
bush to another with uncommon quickness. It really requires little
imagination to believe that the bird is ashamed of itself, and is aware
of its most ridiculous figure.  On first seeing it, one is tempted to
exclaim, "A vilely stuffed specimen has escaped from some museum, and
has come to life again!" It cannot be made to take flight without the
greatest trouble, nor does it run, but only hops.  The various loud
cries which it utters when concealed amongst the bushes, are as strange
as its appearance.  It is said to build its nest in a deep hole beneath
the ground.  I dissected several specimens: the gizzard, which was very
muscular, contained beetles, vegetable fibres, and pebbles.  From this
character, from the length of its legs, scratching feet, membranous
covering to the nostrils, short and arched wings, this bird seems in a
certain degree to connect the thrushes with the gallinaceous order.

The second species (or P. albicollis) is allied to the first in its
general form.  It is called Tapacolo, or "cover your posterior;" and
well does the shameless little bird deserve its name; for it carries
its tail more than erect, that is, inclined backwards towards its head.
It is very common, and frequents the bottoms of hedge-rows, and the
bushes scattered over the barren hills, where scarcely another bird can
exist. In its general manner of feeding, of quickly hopping out of the
thickets and back again, in its desire of concealment, unwillingness to
take flight, and nidification, it bears a close resemblance to the
Turco; but its appearance is not quite so ridiculous.  The Tapacolo is
very crafty: when frightened by any person, it will remain motionless
at the bottom of a bush, and will then, after a little while, try with
much address to crawl away on the opposite side.  It is also an active
bird, and continually making a noise: these noises are various and
strangely odd; some are like the cooing of doves, others like the
bubbling of water, and many defy all similes.  The country people say
it changes its cry five times in the year--according to some change of
season, I suppose. [4]

Two species of humming-birds are common; Trochilus forficatus is found
over a space of 2500 miles on the west coast, from the hot dry country
of Lima, to the forests of Tierra del Fuego--where it may be seen
flitting about in snow-storms.  In the wooded island of Chiloe, which
has an extremely humid climate, this little bird, skipping from side to
side amidst the dripping foliage, is perhaps more abundant than almost
any other kind.  I opened the stomachs of several specimens, shot in
different parts of the continent, and in all, remains of insects were
as numerous as in the stomach of a creeper.  When this species migrates
in the summer southward, it is replaced by the arrival of another
species coming from the north.  This second kind (Trochilus gigas) is a
very large bird for the delicate family to which it belongs: when on
the wing its appearance is singular.  Like others of the genus, it
moves from place to place with a rapidity which may be compared to that
of Syrphus amongst flies, and Sphinx among moths; but whilst hovering
over a flower, it flaps its wings with a very slow and powerful
movement, totally different from that vibratory one common to most of
the species, which produces the humming noise.  I never saw any other
bird where the force of its wings appeared (as in a butterfly) so
powerful in proportion to the weight of its body. When hovering by a
flower, its tail is constantly expanded and shut like a fan, the body
being kept in a nearly vertical position.  This action appears to
steady and support the bird, between the slow movements of its wings.
Although flying from flower to flower in search of food, its stomach
generally contained abundant remains of insects, which I suspect are
much more the object of its search than honey.  The note of this
species, like that of nearly the whole family, is extremely shrill.

[1] Caldeleugh, in Philosoph. Transact. for 1836.

[2] Annales des Sciences Naturelles, March, 1833. M. Gay, a zealous and
able naturalist, was then occupied in studying every branch of natural
history throughout the kingdom of Chile.

[3] Burchess's Travels, vol. ii. p. 45.

[4] It is a remarkable fact, that Molina, though describing in detail
all the birds and animals of Chile, never once mentions this genus, the
species of which are so common, and so remarkable in their habits.  Was
he at a loss how to classify them, and did he consequently think that
silence was the more prudent course?  It is one more instance of the
frequency of omissions by authors, on those very subjects where it
might have been least expected.



CHAPTER XIII

CHILOE AND CHONOS ISLANDS

Chiloe--General Aspect--Boat Excursion--Native Indians--Castro--Tame
Fox--Ascend San Pedro--Chonos Archipelago--Peninsula of Tres
Montes--Granitic Range--Boat-wrecked Sailors--Low's Harbour--Wild
Potato--Formation of Peat--Myopotamus, Otter and Mice--Cheucau and
Barking-bird--Opetiorhynchus--Singular Character of
Ornithology--Petrels.


NOVEMBER 10th.--The Beagle sailed from Valparaiso to the south, for the
purpose of surveying the southern part of Chile, the island of Chiloe,
and the broken land called the Chonos Archipelago, as far south as the
Peninsula of Tres Montes.  On the 21st we anchored in the bay of S.
Carlos, the capital of Chiloe.

This island is about ninety miles long, with a breadth of rather less
than thirty.  The land is hilly, but not mountainous, and is covered by
one great forest, except where a few green patches have been cleared
round the thatched cottages. From a distance the view somewhat
resembles that of Tierra del Fuego; but the woods, when seen nearer,
are incomparably more beautiful.  Many kinds of fine evergreen trees,
and plants with a tropical character, here take the place of the gloomy
beech of the southern shores.  In winter the climate is detestable, and
in summer it is only a little better.  I should think there are few
parts of the world, within the temperate regions, where so much rain
falls.  The winds are very boisterous, and the sky almost always
clouded: to have a week of fine weather is something wonderful.  It is
even difficult to get a single glimpse of the Cordillera: during our
first visit, once only the volcano of Osorno stood out in bold relief,
and that was before sunrise; it was curious to watch, as the sun rose,
the outline gradually fading away in the glare of the eastern sky.

The inhabitants, from their complexion and low stature; appear to have
three-fourths of Indian blood in their veins. They are an humble,
quiet, industrious set of men.  Although the fertile soil, resulting
from the decomposition of the volcanic rocks, supports a rank
vegetation, yet the climate is not favourable to any production which
requires much sunshine to ripen it.  There is very little pasture for
the larger quadrupeds; and in consequence, the staple articles of food
are pigs, potatoes, and fish.  The people all dress in strong woollen
garments, which each family makes for itself, and dyes with indigo of a
dark blue colour.  The arts, however, are in the rudest state;--as may
be seen in their strange fashion of ploughing, their method of
spinning, grinding corn, and in the construction of their boats.  The
forests are so impenetrable, that the land is nowhere cultivated except
near the coast and on the adjoining islets.  Even where paths exist,
they are scarcely passable from the soft and swampy state of the soil.
The inhabitants, like those of Tierra del Fuego, move about chiefly on
the beach or in boats.  Although with plenty to eat, the people are
very poor: there is no demand for labour, and consequently the lower
orders cannot scrape together money sufficient to purchase even the
smallest luxuries.  There is also a great deficiency of a circulating
medium.  I have seen a man bringing on his back a bag of charcoal, with
which to buy some trifle, and another carrying a plank to exchange for
a bottle of wine.  Hence every tradesman must also be a merchant, and
again sell the goods which he takes in exchange.

November  24th.--The yawl and whale-boat were sent under the command of
Mr. (now Captain) Sulivan, to survey the eastern or inland coast of
Chiloe; and with orders to meet the Beagle at the southern extremity of
the island; to which point she would proceed by the outside, so as thus
to circumnavigate the whole.  I accompanied this expedition, but
instead of going in the boats the first day, I hired horses to take me
to Chacao, at the northern extremity of the island. The road followed
the coast; every now and then crossing promontories covered by fine
forests.  In these shaded paths it is absolutely necessary that the
whole road should be made of logs of wood, which are squared and placed
by the side of each other.  From the rays of the sun never penetrating
the evergreen foliage, the ground is so damp and soft, that except by
this means neither man nor horse would be able to pass along.  I
arrived at the village of Chacao shortly after the tents belonging to
the boats were pitched for the night.

The land in this neighbourhood has been extensively cleared, and there
were many quiet and most picturesque nooks in the forest.  Chacao was
formerly the principal port in the island; but many vessels having been
lost, owing to the dangerous currents and rocks in the straits, the
Spanish government burnt the church, and thus arbitrarily compelled the
greater number of inhabitants to migrate to S. Carlos.  We had not long
bivouacked, before the barefooted son of the governor came down to
reconnoitre us.  Seeing the English flag hoisted at the yawl's
mast-head, he asked with the utmost indifference, whether it was always
to fly at Chacao.  In several places the inhabitants were much
astonished at the appearance of men-of-war's boats, and hoped and
believed it was the forerunner of a Spanish fleet, coming to recover
the island from the patriot government of Chile.  All the men in power,
however, had been informed of our intended visit, and were exceedingly
civil.  While we were eating our supper, the governor paid us a visit.
He had been a lieutenant-colonel in the Spanish service, but now was
miserably poor.  He gave us two sheep, and accepted in return two
cotton handkerchiefs, some brass trinkets, and a little tobacco.

25th.--Torrents of rain: we managed, however, to run down the coast as
far as Huapi-lenou.  The whole of this eastern side of Chiloe has one
aspect; it is a plain, broken by valleys and divided into little
islands, and the whole thickly covered with one impervious
blackish-green forest.  On the margins there are some cleared spaces,
surrounding the high-roofed cottages.

26th--The day rose splendidly clear.  The volcano of Orsono was
spouting out volumes of smoke.  This most beautiful mountain, formed
like a perfect cone, and white with snow, stands out in front of the
Cordillera.  Another great volcano, with a saddle-shaped summit, also
emitted from its immense crater little jets of steam.  Subsequently we
saw the lofty-peaked Corcovado--well deserving the name of "el famoso
Corcovado." Thus we beheld, from one point of view, three great active
volcanoes, each about seven thousand feet high.  In addition to this,
far to the south, there were other lofty cones covered with snow,
which, although not known to be active, must be in their origin
volcanic. The line of the Andes is not, in this neighbourhood, nearly
so elevated as in Chile; neither does it appear to form so perfect a
barrier between the regions of the earth.  This great range, although
running in a straight north and south line, owing to an optical
deception, always appeared more or less curved; for the lines drawn
from each peak to the beholder's eye, necessarily converged like the
radii of a semicircle, and as it was not possible (owing to the
clearness of the atmosphere and the absence of all intermediate
objects) to judge how far distant the farthest peaks were off, they
appeared to stand in a flattish semicircle.

Landing at midday, we saw a family of pure Indian extraction. The
father was singularly like York Minster; and some of the younger boys,
with their ruddy complexions, might have been mistaken for Pampas
Indians.  Everything I have seen, convinces me of the close connexion
of the different American tribes, who nevertheless speak distinct
languages. This party could muster but little Spanish, and talked to
each other in their own tongue.  It is a pleasant thing to see the
aborigines advanced to the same degree of civilization, however low
that may be, which their white conquerors have attained.  More to the
south we saw many pure Indians: indeed, all the inhabitants of some of
the islets retain their Indian surnames.  In the census of 1832, there
were in Chiloe and its dependencies forty-two thousand souls; the
greater number of these appear to be of mixed blood.  Eleven thousand
retain their Indian surnames, but it is probable that not nearly all of
these are of a pure breed.  Their manner of life is the same with that
of the other poor inhabitants, and they are all Christians; but it is
said that they yet retain some strange superstitious ceremonies, and
that they pretend to hold communication with the devil in certain
caves.  Formerly, every one convicted of this offence was sent to the
Inquisition at Lima.  Many of the inhabitants who are not included in
the eleven thousand with Indian surnames, cannot be distinguished by
their appearance from Indians. Gomez, the governor of Lemuy, is
descended from noblemen of Spain on both sides; but by constant
intermarriages with the natives the present man is an Indian.  On the
other hand the governor of Quinchao boasts much of his purely kept
Spanish blood.

We reached at night a beautiful little cove, north of the island of
Caucahue.  The people here complained of want of land.  This is partly
owing to their own negligence in not clearing the woods, and partly to
restrictions by the government, which makes it necessary, before buying
ever so small a piece, to pay two shillings to the surveyor for
measuring each quadra (150 yards square), together with whatever price
he fixes for the value of the land.  After his valuation the land must
be put up three times to auction, and if no one bids more, the
purchaser can have it at that rate.  All these exactions must be a
serious check to clearing the ground, where the inhabitants are so
extremely poor.  In most countries, forests are removed without much
difficulty by the aid of fire; but in Chiloe, from the damp nature of
the climate, and the sort of trees, it is necessary first to cut them
down. This is a heavy drawback to the prosperity of Chiloe.  In the
time of the Spaniards the Indians could not hold land; and a family,
after having cleared a piece of ground, might be driven away, and the
property seized by the government. The Chilian authorities are now
performing an act of justice by making retribution to these poor
Indians, giving to each man, according to his grade of life, a certain
portion of land. The value of uncleared ground is very little.  The
government gave Mr. Douglas (the present surveyor, who informed me of
these circumstances) eight and a half square miles of forest near S.
Carlos, in lieu of a debt; and this he sold for 350 dollars, or about
70 pounds sterling.

The two succeeding days were fine, and at night we reached the island
of Quinchao.  This neighbourhood is the most cultivated part of the
Archipelago; for a broad strip of land on the coast of the main island,
as well as on many of the smaller adjoining ones, is almost completely
cleared.  Some of the farm-houses seemed very comfortable.  I was
curious to ascertain how rich any of these people might be, but Mr.
Douglas says that no one can be considered as possessing a regular
income.  One of the richest landowners might possibly accumulate, in a
long industrious life, as much as 1000 pounds sterling; but should this
happen, it would all be stowed away in some secret corner, for it is
the custom of almost every family to have a jar or treasure-chest
buried in the ground.

November 30th.--Early on Sunday morning we reached Castro, the ancient
capital of Chiloe, but now a most forlorn and deserted place. The usual
quadrangular arrangement of Spanish towns could be traced, but the
streets and plaza were coated with fine green turf, on which sheep were
browsing.  The church, which stands in the middle, is entirely built of
plank, and has a picturesque and venerable appearance. The poverty of
the place may be conceived from the fact, that although containing some
hundreds of inhabitants, one of our party was unable anywhere to
purchase either a pound of sugar or an ordinary knife.  No individual
possessed either a watch or a clock; and an old man, who was supposed
to have a good idea of time, was employed to strike the church bell by
guess.  The arrival of our boats was a rare event in this quiet retired
corner of the world; and nearly all the inhabitants came down to the
beach to see us pitch our tents.  They were very civil, and offered us
a house; and one man even sent us a cask of cider as a present.  In the
afternoon we paid our respects to the governor--a quiet old man, who,
in his appearance and manner of life, was scarcely superior to an
English cottager.  At night heavy rain set in, which was hardly
sufficient to drive away from our tents the large circle of lookers-on.
An Indian family, who had come to trade in a canoe from Caylen,
bivouacked near us.  They had no shelter during the rain.  In the
morning I asked a young Indian, who was wet to the skin, how he had
passed the night.  He seemed perfectly content, and answered, "Muy
bien, senor."

December 1st.--We steered for the island of Lemuy.  I was anxious to
examine a reported coal-mine which turned out to be lignite of little
value, in the sandstone (probably of an ancient tertiary epoch) of
which these islands are composed.  When we reached Lemuy we had much
difficulty in finding any place to pitch our tents, for it was
spring-tide, and the land was wooded down to the water's edge.  In a
short time we were surrounded by a large group of the nearly pure
Indian inhabitants.  They were much surprised at our arrival, and said
one to the other, "This is the reason we have seen so many parrots
lately; the cheucau (an odd red-breasted little bird, which inhabits
the thick forest, and utters very peculiar noises) has not cried
'beware' for nothing." They were soon anxious for barter.  Money was
scarcely worth anything, but their eagerness for tobacco was something
quite extraordinary.  After tobacco, indigo came next in value; then
capsicum, old clothes, and gunpowder.  The latter article was required
for a very innocent purpose: each parish has a public musket, and the
gunpowder was wanted for making a noise on their saint or feast days.

The people here live chiefly on shell-fish and potatoes.  At certain
seasons they catch also, in "corrales," or hedges under water, many
fish which are left on the mud-banks as the tide falls.  They
occasionally possess fowls, sheep, goats, pigs, horses, and cattle; the
order in which they are here mentioned, expressing their respective
numbers.  I never saw anything more obliging and humble than the
manners of these people.  They generally began with stating that they
were poor natives of the place, and not Spaniards and that they were in
sad want of tobacco and other comforts. At Caylen, the most southern
island, the sailors bought with a stick of tobacco, of the value of
three-halfpence, two fowls, one of which, the Indian stated, had skin
between its toes, and turned out to be a fine duck; and with some
cotton handkerchiefs, worth three shillings, three sheep and a large
bunch of onions were procured.  The yawl at this place was anchored
some way from the shore, and we had fears for her safety from robbers
during the night.  Our pilot, Mr. Douglas, accordingly told the
constable of the district that we always placed sentinels with loaded
arms and not understanding Spanish, if we saw any person in the dark,
we should assuredly shoot him.  The constable, with much humility,
agreed to the perfect propriety of this arrangement, and promised us
that no one should stir out of his house during that night.

During the four succeeding days we continued sailing southward.  The
general features of the country remained the same, but it was much less
thickly inhabited.  On the large island of Tanqui there was scarcely
one cleared spot, the trees on every side extending their branches over
the sea-beach.  I one day noticed, growing on the sandstone cliffs,
some very fine plants of the panke (Gunnera scabra), which somewhat
resembles the rhubarb on a gigantic scale. The inhabitants eat the
stalks, which are subacid, and tan leather with the roots, and prepare
a black dye from them. The leaf is nearly circular, but deeply indented
on its margin. I measured one which was nearly eight feet in diameter,
and therefore no less than twenty-four in circumference! The stalk is
rather more than a yard high, and each plant sends out four or five of
these enormous leaves, presenting together a very noble appearance.

December 6th.--We reached Caylen, called "el fin del Cristiandad." In
the morning we stopped for a few minutes at a house on the northern end
of Laylec, which was the extreme point of South American Christendom,
and a miserable hovel it was.  The latitude is 43 degs. 10', which is
two degrees farther south than the Rio Negro on the Atlantic coast.
These extreme Christians were very poor, and, under the plea of their
situation, begged for some tobacco.  As a proof of the poverty of these
Indians, I may mention that shortly before this, we had met a man, who
had travelled three days and a half on foot, and had as many to return,
for the sake of recovering the value of a small axe and a few fish. How
very difficult it must be to buy the smallest article, when such
trouble is taken to recover so small a debt.

In the evening we reached the island of San Pedro, where we found the
Beagle at anchor.  In doubling the point, two of the officers landed to
take a round of angles with the theodolite.  A fox (Canis fulvipes), of
a kind said to be peculiar to the island, and very rare in it, and
which is a new species, was sitting on the rocks.  He was so intently
absorbed in watching the work of the officers, that I was able, by
quietly walking up behind, to knock him on the head with my geological
hammer.  This fox, more curious or more scientific, but less wise, than
the generality of his brethren, is now mounted in the museum of the
Zoological Society.

We stayed three days in this harbour, on one of  which Captain Fitz
Roy, with a party, attempted to ascend to the summit of San Pedro.  The
woods here had rather a different appearance from those on the northern
part of the island. The rock, also, being micaceous slate, there was no
beach, but the steep sides dipped directly beneath the water.  The
general aspect in consequence was more like that of Tierra del Fuego
than of Chiloe.  In vain we tried to gain the summit: the forest was so
impenetrable, that no one who has not beheld it can imagine so
entangled a mass of dying and dead trunks.  I am sure that often, for
more than ten minutes together, our feet never touched the ground, and
we were frequently ten or fifteen feet above it, so that the seamen as
a joke called out the soundings.  At other times we crept one after
another on our hands and knees, under the rotten trunks.  In the lower
part of the mountain, noble trees of the Winter's Bark, and a laurel
like the sassafras with fragrant leaves, and others, the names of which
I do not know, were matted together by a trailing bamboo or cane. Here
we were more like fishes struggling in a net than any other animal.  On
the higher parts, brushwood takes the place of larger trees, with here
and there a red cedar or an alerce pine.  I was also pleased to see, at
an elevation of a little less than 1000 feet, our old friend the
southern beech. They were, however, poor stunted trees, and I should
think that this must be nearly their northern limit.  We ultimately
gave up the attempt in despair.

December 10th.--The yawl and whale-boat, with Mr. Sulivan, proceeded on
their survey, but I remained on board the Beagle, which the next day
left San Pedro for the southward. On the 13th we ran into an opening in
the southern part of Guayatecas, or the Chonos Archipelago; and it was
fortunate we did so, for on the following day a storm, worthy of Tierra
del Fuego, raged with great fury.  White massive clouds were piled up
against a dark blue sky, and across them black ragged sheets of vapour
were rapidly driven.  The successive mountain ranges appeared like dim
shadows, and the setting sun cast on the woodland a yellow gleam, much
like that produced by the flame of spirits of wine.  The water was
white with the flying spray, and the wind lulled and roared again
through the rigging: it was an ominous, sublime scene.  During a few
minutes there was a bright rainbow, and it was curious to observe the
effect of the spray, which being carried along the surface of the
water, changed the ordinary semicircle into a circle--a band of
prismatic colours being continued, from both feet of the common arch
across the bay, close to the vessel's side: thus forming a distorted,
but very nearly entire ring.

We stayed here three days.  The weather continued bad: but this did not
much signify, for the surface of the land in all these islands is all
but impassable.  The coast is so very rugged that to attempt to walk in
that direction requires continued scrambling up and down over the sharp
rocks of mica-slate; and as for the woods, our faces, hands, and
shin-bones all bore witness to the maltreatment we received, in merely
attempting to penetrate their forbidden recesses.

December 18th.--We stood out to sea.  On the 20th we bade farewell to
the south, and with a fair wind turned the ship's head northward.  From
Cape Tres Montes we sailed pleasantly along the lofty weather-beaten
coast, which is remarkable for the bold outline of its hills, and the
thick covering of forest even on the almost precipitous flanks.  The
next day a harbour was discovered, which on this dangerous coast might
be of great service to a distressed vessel.  It can easily be
recognized by a hill 1600 feet high, which is even more perfectly
conical than the famous sugar-loaf at Rio de Janeiro.  The next day,
after anchoring, I succeeded in reaching the summit of this hill.  It
was a laborious undertaking, for the sides were so steep that in some
parts it was necessary to use the trees as ladders.  There were also
several extensive brakes of the Fuchsia, covered with its beautiful
drooping flowers, but very difficult to crawl through. In these wild
countries it gives much delight to gain the summit of any mountain.
There is an indefinite expectation of seeing something very strange,
which, however often it may be balked, never failed with me to recur on
each successive attempt.  Every one must know the feeling of triumph
and pride which a grand view from a height communicates to the mind. In
these little frequented countries there is also joined to it some
vanity, that you perhaps are the first man who ever stood on this
pinnacle or admired this view.

A strong desire is always felt to ascertain whether any human being has
previously visited an unfrequented spot. A bit of wood with a nail in
it, is picked up and studied as if it were covered with hieroglyphics.
Possessed with this feeling, I was much interested by finding, on a
wild part of the coast, a bed made of grass beneath a ledge of rock.
Close by it there had been a fire, and the man had used an axe. The
fire, bed, and situation showed the dexterity of an Indian; but he
could scarcely have been an Indian, for the race is in this part
extinct, owing to the Catholic desire of making at one blow Christians
and Slaves.  I had at the time some misgivings that the solitary man
who had made his bed on this wild spot, must have been some poor
shipwrecked sailor, who, in trying to travel up the coast, had here
laid himself down for his dreary night.

December 28th.--The weather continued very bad, but it at last
permitted us to proceed with the survey.  The time hung heavy on our
hands, as it always did when we were delayed from day to day by
successive gales of wind.  In the evening another harbour was
discovered, where we anchored.  Directly afterwards a man was seen
waving a shirt, and a boat was sent which brought back two seamen. A
party of six had run away from an American whaling vessel, and had
landed a little to the southward in a boat, which was shortly
afterwards knocked to pieces by the surf. They had now been wandering
up and down the coast for fifteen months, without knowing which way to
go, or where they were.  What a singular piece of good fortune it was
that this harbour was now discovered!  Had it not been for this one
chance, they might have wandered till they had grown old men, and at
last have perished on this wild coast. Their sufferings had been very
great, and one of their party had lost his life by falling from the
cliffs.  They were sometimes obliged to separate in search of food, and
this explained the bed of the solitary man.  Considering what they had
undergone, I think they had kept a very good reckoning of time, for
they had lost only four days.

December 30th.--We anchored in a snug little cove at the foot of some
high hills, near the northern extremity of Tres Montes.  After
breakfast the next morning, a party ascended one of these mountains,
which was 2400 feet high.  The scenery was remarkable The chief part of
the range was composed of grand, solid, abrupt masses of granite, which
appeared as if they had been coeval with the beginning of the world.
The granite was capped with mica-slate, and this in the lapse of ages
had been worn into strange finger-shaped points.  These two formations,
thus differing in their outlines, agree in being almost destitute of
vegetation.  This barrenness had to our eyes a strange appearance, from
having been so long accustomed to the sight of an almost universal
forest of dark-green trees.  I took much delight in examining the
structure of these mountains.  The complicated and lofty ranges bore a
noble aspect of durability--equally profitless, however, to man and to
all other animals.  Granite to the geologist is classic ground: from
its widespread limits, and its beautiful and compact texture, few rocks
have been more anciently recognised.  Granite has given rise, perhaps,
to more discussion concerning its origin than any other formation. We
generally see it constituting the fundamental rock, and, however
formed, we know it is the deepest layer in the crust of this globe to
which man has penetrated.  The limit of man's knowledge in any subject
possesses a high interest, which is perhaps increased by its close
neighbourhood to the realms of imagination.

January 1st 1835.--The new year is ushered in with the ceremonies
proper to it in these regions.  She lays out no false hopes: a heavy
north-western gale, with steady rain, bespeaks the rising year.  Thank
God, we are not destined here to see the end of it, but hope then to be
in the Pacific Ocean, where a blue sky tells one there is a heaven,--a
something beyond the clouds above our heads.

The north-west winds prevailing for the next four days, we only managed
to cross a great bay, and then anchored in another secure harbour.  I
accompanied the Captain in a boat to the head of a deep creek.  On the
way the number of seals which we saw was quite astonishing: every bit
of flat rock, and parts of the beach, were covered with them.  There
appeared to be of a loving disposition, and lay huddled together, fast
asleep, like so many pigs; but even pigs would have been ashamed of
their dirt, and of the foul smell which came from them.  Each herd was
watched by the patient but inauspicious eyes of the turkey-buzzard.
This disgusting bird, with its bald scarlet head, formed to wallow in
putridity, is very common on the west coast, and their attendance on
the seals shows on what they rely for their food.  We found the water
(probably only that of the surface) nearly fresh: this was caused by
the number of torrents which, in the form of cascades, came tumbling
over the bold granite mountains into the sea.  The fresh water attracts
the fish, and these bring many terns, gulls, and two kinds of
cormorant.  We saw also a pair of the beautiful black-necked swans, and
several small sea-otters, the fur of which is held in such high
estimation.  In returning, we were again amused by the impetuous manner
in which the heap of seals, old and young, tumbled into the water as
the boat passed.  They did not remain long under water, but rising,
followed us with outstretched necks, expressing great wonder and
curiosity.

7th.--Having run up the coast, we anchored near the northern end of the
Chonos Archipelago, in Low's Harbour, where we remained a week. The
islands were here, as in Chiloe, composed of a stratified, soft,
littoral deposit; and the vegetation in consequence was beautifully
luxuriant.  The woods came down to the sea-beach, just in the manner of
an evergreen shrubbery over a gravel walk.  We also enjoyed from the
anchorage a splendid view of four great snowy cones of the Cordillera,
including "el famoso Corcovado;" the range itself had in this latitude
so little height, that few parts of it appeared above the tops of the
neighbouring islets.  We found here a party of five men from Caylen,
"el fin del Cristiandad," who had most adventurously crossed in their
miserable boat-canoe, for the purpose of fishing, the open space of sea
which separates Chonos from Chiloe.  These islands will, in all
probability, in a short time become peopled like those adjoining the
coast of Chiloe.


The wild potato grows on these islands in great abundance, on the
sandy, shelly soil near the sea-beach.  The tallest plant was four feet
in height.  The tubers were generally small, but I found one, of an
oval shape, two inches in diameter: they resembled in every respect,
and had the same smell as English potatoes; but when boiled they shrunk
much, and were watery and insipid, without any bitter taste.  They are
undoubtedly here indigenous: they grow as far south, according to Mr.
Low, as lat. 50 degs., and are called Aquinas by the wild Indians of
that part: the Chilotan Indians have a different name for them.
Professor Henslow, who has examined the dried specimens which I brought
home, says that they are the same with those described by Mr. Sabine
[1] from Valparaiso, but that they form a variety which by some
botanists has been considered as specifically distinct.  It is
remarkable that the same plant should be found on the sterile mountains
of central Chile, where a drop of rain does not fall for more than six
months, and within the damp forests of these southern islands.

In the central parts of the Chonos Archipelago (lat. 45 degs.), the
forest has very much the same character with that along the whole west
coast, for 600 miles southward to Cape Horn. The arborescent grass of
Chiloe is not found here; while the beech of Tierra del Fuego grows to
a good size, and forms a considerable proportion of the wood; not,
however, in the same exclusive manner as it does farther southward.
Cryptogamic plants here find a most congenial climate.  In the Strait
of Magellan, as I have before remarked, the country appears too cold
and wet to allow of their arriving at perfection; but in these islands,
within the forest, the number of species and great abundance of mosses,
lichens, and small ferns, is quite extraordinary. [2] In Tierra del
Fuego trees grow only on the hill-sides; every level piece of land
being invariably covered by a thick bed of peat; but in Chiloe flat
land supports the most luxuriant forests.  Here, within the Chonos
Archipelago, the nature of the climate more closely approaches that of
Tierra del Fuego than that of northern Chiloe; for every patch of level
ground is covered by two species of plants (Astelia pumila and Donatia
magellanica), which by their joint decay compose a thick bed of elastic
peat.

In Tierra del Fuego, above the region of woodland, the former of these
eminently sociable plants is the chief agent in the production of peat.
Fresh leaves are always succeeding one to the other round the central
tap-root, the lower ones soon decay, and in tracing a root downwards in
the peat, the leaves, yet holding their place, can be observed passing
through every stage of decomposition, till the whole becomes blended in
one confused mass.  The Astelia is assisted by a few other
plants,--here and there a small creeping Myrtus (M. nummularia), with a
woody stem like our cranberry and with a sweet berry,--an Empetrum (E.
rubrum), like our heath,--a rush (Juncus grandiflorus), are nearly the
only ones that grow on the swampy surface.  These plants, though
possessing a very close general resemblance to the English species of
the same genera, are different.  In the more level parts of the
country, the surface of the peat is broken up into little pools of
water, which stand at different heights, and appear as if artificially
excavated.  Small streams of water, flowing underground, complete the
disorganization of the vegetable matter, and consolidate the whole.

The climate of the southern part of America appears particularly
favourable to the production of peat.  In the Falkland Islands almost
every kind of plant, even the coarse grass which covers the whole
surface of the land, becomes converted into this substance: scarcely
any situation checks its growth; some of the beds are as much as twelve
feet thick, and the lower part becomes so solid when dry, that it will
hardly burn.  Although every plant lends its aid, yet in most parts the
Astelia is the most efficient.  It is rather a singular circumstance,
as being so very different from what occurs in Europe, that I nowhere
saw moss forming by its decay any portion of the peat in South America.
With respect to the northern limit, at which the climate allows of that
peculiar kind of slow decomposition which is necessary for its
production, I believe that in Chiloe (lat. 41 to 42 degs.), although
there is much swampy ground, no well-characterized peat occurs: but in
the Chonos Islands, three degrees farther southward, we have seen that
it is abundant.  On the eastern coast in La Plata (lat. 35 degs.) I was
told by a Spanish resident who had visited Ireland, that he had often
sought for this substance, but had never been able to find any.  He
showed me, as the nearest approach to it which he had discovered, a
black peaty soil, so penetrated with roots as to allow of an extremely
slow and imperfect combustion.


The zoology of these broken islets of the Chonos Archipelago is, as
might have been expected, very poor.  Of quadrupeds two aquatic kinds
are common.  The Myopotamus Coypus (like a beaver, but with a round
tail) is well known from its fine fur, which is an object of trade
throughout the tributaries of La Plata.  It here, however, exclusively
frequents salt water; which same circumstance has been mentioned as
sometimes occurring with the great rodent, the Capybara.  A small
sea-otter is very numerous; this animal does not feed exclusively on
fish, but, like the seals, draws a large supply from a small red crab,
which swims in shoals near the surface of the water.  Mr. Bynoe saw one
in Tierra del Fuego eating a cuttle-fish; and at Low's Harbour, another
was killed in the act of carrying to its hole a large volute shell.  At
one place I caught in a trap a singular little mouse (M. brachiotis);
it appeared common on several of the islets, but the Chilotans at Low's
Harbour said that it was not found in all.  What a succession of
chances, [3] or what changes of level must have been brought into play,
thus to spread these small animals throughout this broken archipelago!

In all parts of Chiloe and Chonos, two very strange birds occur, which
are allied to, and replace, the Turco and Tapacolo of central Chile.
One is called by the inhabitants "Cheucau" (Pteroptochos rubecula): it
frequents the most gloomy and retired spots within the damp forests.
Sometimes, although its cry may be heard close at hand, let a person
watch ever so attentively he will not see the cheucau; at other times,
let him stand motionless and the red-breasted little bird will approach
within a few feet in the most familiar manner.  It then busily hops
about the entangled mass of rotting cones and branches, with its little
tail cocked upwards. The cheucau is held in superstitious fear by the
Chilotans, on account of its strange and varied cries.  There are three
very distinct cries: One is called "chiduco," and is an omen of good;
another, "huitreu," which is extremely unfavourable; and a third, which
I have forgotten.  These words are given in imitation of the noises;
and the natives are in some things absolutely governed by them.  The
Chilotans assuredly have chosen a most comical little creature for
their prophet. An allied species, but rather larger, is called by the
natives "Guid-guid" (Pteroptochos Tarnii), and by the English the
barking-bird.  This latter name is well given; for I defy any one at
first to feel certain that a small dog is not yelping somewhere in the
forest.  Just as with the cheucau, a person will sometimes hear the
bark close by, but in vain many endeavour by watching, and with still
less chance by beating the bushes, to see the bird; yet at other times
the guid-guid fearlessly comes near.  Its manner of feeding and its
general habits are very similar to those of the cheucau.

On the coast, [4] a small dusky-coloured bird (Opetiorhynchus
Patagonicus) is very common.  It is remarkable from its quiet habits;
it lives entirely on the sea-beach, like a sandpiper.  Besides these
birds only few others inhabit this broken land.  In my rough notes I
describe the strange noises, which, although frequently heard within
these gloomy forests, yet scarcely disturb the general silence.  The
yelping of the guid-guid, and the sudden whew-whew of the cheucau,
sometimes come from afar off, and sometimes from close at hand; the
little black wren of Tierra del Fuego occasionally adds its cry; the
creeper (Oxyurus) follows the intruder screaming and twittering; the
humming-bird may be seen every now and then darting from side to side,
and emitting, like an insect, its shrill chirp; lastly, from the top of
some lofty tree the indistinct but plaintive note of the white-tufted
tyrant-flycatcher (Myiobius) may be noticed. From the great
preponderance in most countries of certain common genera of birds, such
as the finches, one feels at first surprised at meeting with the
peculiar forms above enumerated, as the commonest birds in any
district.  In central Chile two of them, namely, the Oxyurus and
Scytalopus, occur, although most rarely.  When finding, as in this
case, animals which seem to play so insignificant a part in the great
scheme of nature, one is apt to wonder why they were created.

But it should always be recollected, that in some other country perhaps
they are essential members of society, or at some former period may
have been so.  If America south of 37 degs. were sunk beneath the
waters of the ocean, these two birds might continue to exist in central
Chile for a long period, but it is very improbable that their numbers
would increase.  We should then see a case which must inevitably have
happened with very many animals.

These southern seas are frequented by several species of Petrels: the
largest kind, Procellaria gigantea, or nelly (quebrantahuesos, or
break-bones, of the Spaniards), is a common bird, both in the inland
channels and on the open sea. In its habits and manner of flight, there
is a very close resemblance with the albatross; and as with the
albatross, a person may watch it for hours together without seeing on
what it feeds.  The "break-bones" is, however, a rapacious bird, for it
was observed by some of the officers at Port St. Antonio chasing a
diver, which tried to escape by diving and flying, but was continually
struck down, and at last killed by a blow on its head.  At Port St.
Julian these great petrels were seen killing and devouring young gulls.
A second species (Puffinus cinereus), which is common to Europe, Cape
Horn, and the coast of Peru, is of much smaller size than the P.
gigantea, but, like it, of a dirty black colour.  It generally
frequents the inland sounds in very large flocks: I do not think I ever
saw so many birds of any other sort together, as I once saw of these
behind the island of Chiloe. Hundreds of thousands flew in an irregular
line for several hours in one direction.  When part of the flock
settled on the water the surface was blackened, and a noise proceeded
from them as of human beings talking in the distance.

There are several other species of petrels, but I will only mention one
other kind, the Pelacanoides Berardi which offers an example of those
extraordinary cases, of a bird evidently belonging to one well-marked
family, yet both in its habits and structure allied to a very distinct
tribe.  This bird never leaves the quiet inland sounds.  When disturbed
it dives to a distance, and on coming to the surface, with the same
movement takes flight.  After flying by a rapid movement of its short
wings for a space in a straight line, it drops, as if struck dead, and
dives again.  The form of its beak and nostrils, length of foot, and
even the colouring of its plumage, show that this bird is a petrel: on
the other hand, its short wings and consequent little power of flight,
its form of body and shape of tail, the absence of a hind toe to its
foot, its habit of diving, and its choice of situation, make it at
first doubtful whether its relationship is not equally close with the
auks.  It would undoubtedly be mistaken for an auk, when seen from a
distance, either on the wing, or when diving and quietly swimming about
the retired channels of Tierra del Fuego.

[1] Horticultural Transact., vol. v. p. 249. Mr. Caldeleugh sent home
two tubers, which, being well manured, even the first season produced
numerous potatoes and an abundance of leaves.  See Humboldt's
interesting discussion on this plant, which it appears was unknown in
Mexico,--in Polit. Essay on New Spain, book iv. chap. ix.

[2] By sweeping with my insect-net, I procured from these situations a
considerable number of minute insects, of the family of Staphylinidae,
and others allied to Pselaphus, and minute Hymenoptera.  But the most
characteristic family in number, both of individuals and species,
throughout the more open parts of Chiloe and Chonos is that of
Telephoridae.

[3] It is said that some rapacious birds bring their prey alive to
their nests.  If so, in the course of centuries, every now and then,
one might escape from the young birds. Some such agency is necessary,
to account for the distribution of the smaller gnawing animals on
islands not very near each other.

[4] I may mention, as a proof of how great a difference there is
between the seasons of the wooded and the open parts of this coast,
that on September 20th, in lat. 34 degs., these birds had young ones in
the nest, while among the Chonos Islands, three months later in the
summer, they were only laying, the difference in latitude between these
two places being about 700 miles.



CHAPTER XIV

CHILOE AND CONCEPCION: GREAT EARTHQUAKE

San Carlos, Chiloe--Osorno in eruption, contemporaneously with
Aconcagua and Coseguina--Ride to Cucao--Impenetrable Forests--Valdivia
Indians--Earthquake--Concepcion--Great Earthquake--Rocks
fissured--Appearance of the former Towns--The Sea Black and
Boiling--Direction of the Vibrations--Stones twisted round--Great
Wave--Permanent Elevation of the Land--Area of Volcanic Phenomena--The
connection between the Elevatory and Eruptive Forces--Cause of
Earthquakes--Slow Elevation of Mountain-chains.


ON JANUARY the 15th we sailed from Low's Harbour, and three days
afterwards anchored a second time in the bay of S. Carlos in Chiloe. On
the night of the 19th the volcano of Osorno was in action.  At midnight
the sentry observed something like a large star, which gradually
increased in size till about three o'clock, when it presented a very
magnificent spectacle.  By the aid of a glass, dark objects, in
constant succession, were seen, in the midst of a great glare of red
light, to be thrown up and to fall down. The light was sufficient to
cast on the water a long bright reflection.  Large masses of molten
matter seem very commonly to be cast out of the craters in this part of
the Cordillera. I was assured that when the Corcovado is in eruption,
great masses are projected upwards and are seen to burst in the air,
assuming many fantastical forms, such as trees: their size must be
immense, for they can be distinguished from the high land behind S.
Carlos, which is no less than ninety-three miles from the Corcovado. In
the morning the volcano became tranquil.

I was surprised at hearing afterwards that Aconcagua in Chile, 480
miles northwards, was in action on the same night; and still more
surprised to hear that the great eruption of Coseguina (2700 miles
north of Aconcagua), accompanied by an earthquake felt over a 1000
miles, also occurred within six  hours of this same time.  This
coincidence is the more remarkable, as Coseguina had been dormant for
twenty-six years; and Aconcagua most rarely shows any signs of action.
It is difficult even to conjecture whether this coincidence was
accidental, or shows some subterranean connection.  If Vesuvius, Etna,
and Hecla in Iceland (all three relatively nearer each other than the
corresponding points in South America), suddenly burst forth in
eruption on the same night, the coincidence would be thought
remarkable; but it is far more remarkable in this case, where the three
vents fall on the same great mountain-chain, and where the vast plains
along the entire eastern coast, and the upraised recent shells along
more than 2000 miles on the western coast, show in how equable and
connected a manner the elevatory forces have acted.

Captain Fitz Roy being anxious that some bearings should be taken on
the outer coast of Chiloe, it was planned that Mr. King and myself
should ride to Castro, and thence across the island to the Capella de
Cucao, situated on the west coast.  Having hired horses and a guide, we
set out on the morning of the 22nd.  We had not proceeded far, before
we were joined by a woman and two boys, who were bent on the same
journey.  Every one on this road acts on a "hail fellow well met"
fashion; and one may here enjoy the privilege, so rare in South
America, of travelling without fire-arms. At first, the country
consisted of a succession of hills and valleys: nearer to Castro it
became very level.  The road itself is a curious affair; it consists in
its whole length, with the exception of very few parts, of great logs
of wood, which are either broad and laid longitudinally, or narrow and
placed transversely.  In summer the road is not very bad; but in
winter, when the wood is rendered slippery from rain, travelling is
exceedingly difficult.  At that time of the year, the ground on each
side becomes a morass, and is often overflowed: hence it is necessary
that the longitudinal logs should be fastened down by transverse poles,
which are pegged on each side into the earth.  These pegs render a fall
from a horse dangerous, as the chance of alighting on one of them is
not small.  It is remarkable, however, how active custom has made the
Chilotan horses.  In crossing bad parts, where the logs had been
displaced, they skipped from one to the other, almost with the
quickness and certainty of a dog.  On both hands the road is bordered
by the lofty forest-trees, with their bases matted together by canes.
When occasionally a long reach of this avenue could be beheld, it
presented a curious scene of uniformity: the white line of logs,
narrowing in perspective, became hidden by the gloomy forest, or
terminated in a zigzag which ascended some steep hill.

Although the distance from S. Carlos to Castro is only twelve leagues
in a straight line, the formation of the road must have been a great
labour.  I was told that several people had formerly lost their lives
in attempting to cross the forest.  The first who succeeded was an
Indian, who cut his way through the canes in eight days, and reached S.
Carlos: he was rewarded by the Spanish government with a grant of land.
During the summer, many of the Indians wander about the forests (but
chiefly in the higher parts, where the woods are not quite so thick) in
search of the half-wild cattle which live on the leaves of the cane and
certain trees.  It was one of these huntsmen who by chance discovered,
a few years since, an English vessel, which had been wrecked on the
outer coast.  The crew were beginning to fail in provisions, and it is
not probable that, without the aid of this man, they would ever have
extricated themselves from these scarcely penetrable woods.  As it was,
one seaman died on the march, from fatigue.  The Indians in these
excursions steer by the sun; so that if there is a continuance of
cloudy weather, they can not travel.

The day was beautiful, and the number of trees which were in full
flower perfumed the air; yet even this could hardly dissipate the
effects of the gloomy dampness of the forest.  Moreover, the many dead
trunks that stand like skeletons, never fail to give to these primeval
woods a character of solemnity, absent in those of countries long
civilized.  Shortly after sunset we bivouacked for the night.  Our
female companion, who was rather good-looking, belonged to one of the
most respectable families in Castro: she rode, however, astride, and
without shoes or stockings.  I was surprised at the total want of pride
shown by her and her brother.  They  brought food with them, but at all
our meals sat watching Mr. King and myself whilst eating, till we were
fairly shamed into feeding the whole party.  The night was cloudless;
and while lying in our beds, we enjoyed the sight (and it is a high
enjoyment) of the multitude of stars which illumined the darkness of
the forest.

January 23rd.--We rose early in the morning, and reached the pretty
quiet town of Castro by two o'clock.  The old governor had died since
our last visit, and a Chileno was acting in his place.  We had a letter
of introduction to Don Pedro, whom we found exceedingly hospitable and
kind, and more disinterested than is usual on this side of the
continent.  The next day Don Pedro procured us fresh horses, and
offered to accompany us himself.  We proceeded to the south--generally
following the coast, and passing through several hamlets, each with its
large barn-like chapel built of wood.  At Vilipilli, Don Pedro asked
the commandant to give us a guide to Cucao.  The old gentleman offered
to come himself; but for a long time nothing would persuade him that
two Englishmen really wished to go to such an out-of-the-way place as
Cucao.  We were thus accompanied by the two greatest aristocrats in the
country, as was plainly to be seen in the manner of all the poorer
Indians towards them.  At Chonchi we struck across the island,
following intricate winding paths, sometimes passing through
magnificent forests, and sometimes through pretty cleared spots,
abounding with corn and potato crops.  This undulating woody country,
partially cultivated, reminded me of the wilder parts of England, and
therefore had to my eye a most fascinating aspect.  At Vilinco, which
is situated on the borders of the lake of Cucao, only a few fields were
cleared; and all the inhabitants appeared to be Indians.  This lake is
twelve miles long, and runs in an east and west direction.  From local
circumstances, the sea-breeze blows very regularly during the day, and
during the night it falls calm: this has given rise to strange
exaggerations, for the phenomenon, as described to us at S. Carlos, was
quite a prodigy.

The road to Cucao was so very bad that we determined to embark in a
_periagua_.  The commandant, in the most authoritative manner, ordered
six Indians to get ready to pull us over, without deigning to tell them
whether they would be paid.  The periagua is a strange rough boat, but
the crew were still stranger: I doubt if six uglier little men ever got
into a boat together.  They pulled, however, very well and cheerfully.
The stroke-oarsman gabbled Indian, and uttered strange cries, much
after the fashion of a pig-driver driving his pigs.  We started with a
light breeze against us, but yet reached the Capella de Cucao before it
was late.  The country on each side of the lake was one unbroken
forest.  In the same periagua with us, a cow was embarked.  To get so
large an animal into a small boat appears at first a difficulty, but
the Indians managed it in a minute.  They brought the cow alongside the
boat, which was heeled towards her; then placing two oars under her
belly, with their ends resting on the gunwale, by the aid of these
levers they fairly tumbled the poor beast heels over head into the
bottom of the boat, and then lashed her down with ropes.  At Cucao we
found an uninhabited hovel (which is the residence of the padre when he
pays this Capella a visit), where, lighting a fire, we cooked our
supper, and were very comfortable.

The district of Cucao is the only inhabited part on the whole west
coast of Chiloe.  It contains about thirty or forty Indian families,
who are scattered along four or five miles of the shore.  They are very
much secluded from the rest of Chiloe, and have scarcely any sort of
commerce, except sometimes in a little oil, which they get from
seal-blubber. They are tolerably dressed in clothes of their own
manufacture, and they have plenty to eat.  They seemed, however,
discontented, yet humble to a degree which it was quite painful to
witness.  These feelings are, I think, chiefly to be attributed to the
harsh and authoritative manner in which they are treated by their
rulers.  Our companions, although so very civil to us, behaved to the
poor Indians as if they had been slaves, rather than free men.  They
ordered provisions and the use of their horses, without ever
condescending to say how much, or indeed whether the owners should be
paid at all.  In the morning, being left alone with these poor people,
we soon ingratiated ourselves by presents of cigars and mate.  A lump
of white sugar was divided between all present, and tasted with the
greatest curiosity.  The Indians ended all their complaints by saying,
"And it is only because we are poor Indians, and know nothing; but it
was not so when we had a King."

The next day after breakfast, we rode a few miles northward to Punta
Huantamo.  The road lay along a very broad beach, on which, even after
so many fine days, a terrible surf was breaking.  I was assured that
after a heavy gale, the roar can be heard at night even at Castro, a
distance of no less than twenty-one sea-miles across a hilly and wooded
country.  We had some difficulty in reaching the point, owing to the
intolerably bad paths; for everywhere in the shade the ground soon
becomes a perfect quagmire.  The point itself is a bold rocky hill.  It
is covered by a plant allied, I believe, to Bromelia, and called by the
inhabitants Chepones. In scrambling through the beds, our hands were
very much scratched.  I was amused by observing the precaution our
Indian guide took, in turning up his trousers, thinking that they were
more delicate than his own hard skin.  This plant bears a fruit, in
shape like an artichoke, in which a number of seed-vessels are packed:
these contain a pleasant sweet pulp, here much esteemed.  I saw at
Low's Harbour the Chilotans making chichi, or cider, with this fruit:
so true is it, as Humboldt remarks, that almost everywhere man finds
means of preparing some kind of beverage from the vegetable kingdom.
The savages, however, of Tierra del Fuego, and I believe of Australia,
have not advanced thus far in the arts.

The coast to the north of Punta Huantamo is exceedingly rugged and
broken, and is fronted by many breakers, on which the sea is eternally
roaring.  Mr. King and myself were anxious to return, if it had been
possible, on foot along this coast; but even the Indians said it was
quite impracticable.  We were told that men have crossed by striking
directly through the woods from Cucao to S. Carlos, but never by the
coast.  On these expeditions, the Indians carry with them only roasted
corn, and of this they eat sparingly twice a day.

26th.--Re-embarking in the periagua, we returned across the lake, and
then mounted our horses.  The whole of Chiloe took advantage of this
week of unusually fine weather, to clear the ground by burning.  In
every direction volumes of smoke were curling upwards.  Although the
inhabitants were so assiduous in setting fire to every part of the
wood, yet I did not see a single fire which they had succeeded in
making extensive.  We dined with our friend the commandant, and did not
reach Castro till after dark.  The next morning we started very early.
After having ridden for some time, we obtained from the brow of a steep
hill an extensive view (and it is a rare thing on this road) of the
great forest. Over the horizon of trees, the volcano of Corcovado, and
the great flat-topped one to the north, stood out in proud
pre-eminence: scarcely another peak in the long range showed its snowy
summit.  I hope it will be long before I forget this farewell view of
the magnificent Cordillera fronting Chiloe.  At night we bivouacked
under a cloudless sky, and the next morning reached S. Carlos.  We
arrived on the right day, for before evening heavy rain commenced.

February 4th.--Sailed from Chiloe.  During the last week I made several
short excursions.  One was to examine a great bed of now-existing
shells, elevated 350 feet above the level of the sea: from among these
shells, large forest-trees were growing.  Another ride was to P.
Huechucucuy. I had with me a guide who knew the country far too well;
for he would pertinaciously tell me endless Indian names for every
little point, rivulet, and creek.  In the same manner as in Tierra del
Fuego, the Indian language appears singularly well adapted for
attaching names to the most trivial features of the land.  I believe
every one was glad to say farewell to Chiloe; yet if we could forget
the gloom and ceaseless rain of winter, Chiloe might pass for a
charming island. There is also something very attractive in the
simplicity and humble politeness of the poor inhabitants.

We steered northward along shore, but owing to thick weather did not
reach Valdivia till the night of the 8th.  The next morning the boat
proceeded to the town, which is distant about ten miles.  We followed
the course of the river, occasionally passing a few hovels, and patches
of ground cleared out of the otherwise unbroken forest; and sometimes
meeting a canoe with an Indian family.  The town is situated on the low
banks of the stream, and is so completely buried in a wood of
apple-trees that the streets are merely paths in an orchard. I have
never seen any country, where apple-trees appeared to thrive so well as
in this damp part of South America: on the borders of the roads there
were many young trees evidently self-grown.  In Chiloe the inhabitants
possess a marvellously short method of making an orchard.  At the lower
part of almost every branch, small, conical, brown, wrinkled points
project: these are always ready to change into roots, as may sometimes
be seen, where any mud has been accidentally splashed against the tree.
A branch as thick as a man's thigh is chosen in the early spring, and
is cut off just beneath a group of these points, all the smaller
branches are lopped off, and it is then placed about two feet deep in
the ground.  During the ensuing summer the stump throws out long
shoots, and sometimes even bears fruit: I was shown one which had
produced as many as twenty-three apples, but this was thought very
unusual.  In the third season the stump is changed (as I have myself
seen) into a well-wooded tree, loaded with fruit.  An old man near
Valdivia illustrated his motto, "Necesidad es la madre del invencion,"
by giving an account of the several useful things he manufactured from
his apples.  After making cider, and likewise wine, he extracted from
the refuse a white and finely flavoured spirit; by another process he
procured a sweet treacle, or, as he called it, honey.  His children and
pigs seemed almost to live, during this season of the year, in his
orchard.

February 11th.--I set out with a guide on a short ride, in which,
however, I managed to see singularly little, either of the geology of
the country or of its inhabitants.  There is not much cleared land near
Valdivia: after crossing a river at the distance of a few miles, we
entered the forest, and then passed only one miserable hovel, before
reaching our sleeping-place for the night.  The short difference in
latitude, of 150 miles, has given a new aspect to the forest compared
with that of Chiloe.  This is owing to a slightly different proportion
in the kinds of trees.  The evergreens do not appear to be quite so
numerous, and the forest in consequence has a brighter tint.  As in
Chiloe, the lower parts are matted together by canes: here also another
kind (resembling the bamboo of Brazil and about twenty feet in height)
grows in clusters, and ornaments the banks of some of the streams in a
very pretty manner.  It is with this plant that the Indians make their
chuzos, or long tapering spears. Our resting-house was so dirty that I
preferred sleeping outside: on these journeys the first night is
generally very uncomfortable, because one is not accustomed to the
tickling and biting of the fleas.  I am sure, in the morning, there was
not a space on my legs the size of a shilling which had not its little
red mark where the flea had feasted.

12th.--We continued to ride through the uncleared forest; only
occasionally meeting an Indian on horseback, or a troop of fine mules
bringing alerce-planks and corn from the southern plains.  In the
afternoon one of the horses knocked up: we were then on a brow of a
hill, which commanded a fine view of the Llanos.  The view of these
open plains was very refreshing, after being hemmed in and buried in
the wilderness of trees.  The uniformity of a forest soon becomes very
wearisome.  This west coast makes me remember with pleasure the free,
unbounded plains of Patagonia; yet, with the true spirit of
contradiction, I cannot forget how sublime is the silence of the
forest.  The Llanos are the most fertile and thickly peopled parts of
the country, as they possess the immense advantage of being nearly free
from trees.  Before leaving the forest we crossed some flat little
lawns, around which single trees stood, as in an English park: I have
often noticed with surprise, in wooded undulatory districts, that the
quite level parts have been destitute of trees.  On account of the
tired horse, I determined to stop at the Mission of Cudico, to the
friar of which I had a letter of introduction. Cudico is an
intermediate district between the forest and the Llanos.  There are a
good many cottages, with patches of corn and potatoes, nearly all
belonging to Indians. The tribes dependent on Valdivia are "reducidos y
cristianos." The Indians farther northward, about Arauco and Imperial,
are still very wild, and not converted; but they have all much
intercourse with the Spaniards.  The padre said that the Christian
Indians did not much like coming to mass, but that otherwise they
showed respect for religion. The greatest difficulty is in making them
observe the ceremonies of marriage.  The wild Indians take as many
wives as they can support, and a cacique will sometimes have more than
ten: on entering his house, the number may be told by that of the
separate fires.  Each wife lives a week in turn with the cacique; but
all are employed in weaving ponchos, etc., for his profit.  To be the
wife of a cacique, is an honour much sought after by the Indian women.

The men of all these tribes wear a coarse woolen poncho: those south of
Valdivia wear short trousers, and those north of it a petticoat, like
the chilipa of the Gauchos.  All have their long hair bound by a
scarlet fillet, but with no other covering on their heads.  These
Indians are good-sized men; their cheek-bones are prominent, and in
general appearance they resemble the great American family to which
they belong; but their physiognomy seemed to me to be slightly
different from that of any other tribe which I had before seen.  Their
expression is generally grave, and even austere, and possesses much
character: this may pass either for honest bluntness or fierce
determination.  The long black hair, the grave and much-lined features,
and the dark complexion, called to my mind old portraits of James I. On
the road we met with none of that humble politeness so universal in
Chiloe.  Some gave their "mari-mari" (good morning) with promptness,
but the greater number did not seem inclined to offer any salute.  This
independence of manners is probably a consequence of their long wars,
and the repeated victories which they alone, of all the tribes in
America, have gained over the Spaniards.

I spent the evening very pleasantly, talking with the padre.  He was
exceedingly kind and hospitable; and coming from Santiago, had
contrived to surround himself with some few comforts.  Being a man of
some little education, he bitterly complained of the total want of
society.  With no particular zeal for religion, no business or pursuit,
how completely must this man's life be wasted!  The next day, on our
return, we met seven very wild-looking Indians, of whom some were
caciques that had just received from the Chilian government their
yearly small stipend for having long remained faithful.  They were
fine-looking men, and they rode one after the other, with most gloomy
faces.  An old cacique, who headed them, had been, I suppose, more
excessively drunk than the rest, for he seemed extremely grave and very
crabbed.  Shortly before this, two Indians joined us, who were
travelling from a distant mission to Valdivia concerning some lawsuit.
One was a good-humoured old man, but from his wrinkled beardless face
looked more like an old woman than a man.  I frequently presented both
of them with cigars; and though ready to receive them, and I dare say
grateful, they would hardly condescend to thank me.  A Chilotan Indian
would have taken off his hat, and given his "Dios le page!" The
travelling was very tedious, both from the badness of the roads, and
from the number of great fallen trees, which it was necessary either to
leap over or to avoid by making long circuits.  We slept on the road,
and next morning reached Valdivia, whence I proceeded on board.

A few days afterwards I crossed the bay with a party of officers, and
landed near the fort called Niebla.  The buildings were in a most
ruinous state, and the gun-carriages quite rotten.  Mr. Wickham
remarked to the commanding officer, that with one discharge they would
certainly all fall to pieces.  The poor man, trying to put a good face
upon it, gravely replied, "No, I am sure, sir, they would stand two!"
The Spaniards must have intended to have made this place impregnable.
There is now lying in the middle of the courtyard a little mountain of
mortar, which rivals in hardness the rock on which it is placed.  It
was brought from Chile, and cost 7000 dollars.  The revolution having
broken out, prevented its being applied to any purpose, and now it
remains a monument of the fallen greatness of Spain.

I wanted to go to a house about a mile and a half distant, but my guide
said it was quite impossible to penetrate the wood in a straight line.
He offered, however, to lead me, by following obscure cattle-tracks,
the shortest way: the walk, nevertheless, took no less than three
hours!  This man is employed in hunting strayed cattle; yet, well as he
must know the woods, he was not long since lost for two whole days, and
had nothing to eat.  These facts convey a good idea of the
impracticability of the forests of these countries. A question often
occurred to me--how long does any vestige of a fallen tree remain? This
man showed me one which a party of fugitive royalists had cut down
fourteen years ago; and taking this as a criterion, I should think a
bole a foot and a half in diameter would in thirty years be changed
into a heap of mould.

February 20th.--This day has been memorable in the annals of Valdivia,
for the most severe earthquake experienced by the oldest inhabitant.  I
happened to be on shore, and was lying down in the wood to rest myself.
It came on suddenly, and lasted two minutes, but the time appeared much
longer.  The rocking of the ground was very sensible. The undulations
appeared to my companion and myself to come from due east, whilst
others thought they proceeded from south-west: this shows how difficult
it sometimes is to perceive the directions of the vibrations.  There
was no difficulty in standing upright, but the motion made me almost
giddy: it was something like the movement of a vessel in a little
cross-ripple, or still more like that felt by a person skating over
thin ice, which bends under the weight of his body. A bad earthquake at
once destroys our oldest associations: the earth, the very emblem of
solidity, has moved beneath our feet like a thin crust over a
fluid;--one second of time has created in the mind a strange idea of
insecurity, which hours of reflection would not have produced.  In the
forest, as a breeze moved the trees, I felt only the earth tremble, but
saw no other effect.  Captain Fitz Roy and some officers were at the
town during the shock, and there the scene was more striking; for
although the houses, from being built of wood, did not fall, they were
violently shaken, and the boards creaked and rattled together.  The
people rushed out of doors in the greatest alarm.  It is these
accompaniments that create that perfect horror of earthquakes,
experienced by all who have thus seen, as well as felt, their effects.
Within the forest it was a deeply interesting, but by no means an
awe-exciting phenomenon.  The tides were very curiously affected. The
great shock took place at the time of low water; and an old woman who
was on the beach told me that the water flowed very quickly, but not in
great waves, to high-water mark, and then as quickly returned to its
proper level; this was also evident by the line of wet sand.  The same
kind of quick but quiet movement in the tide happened a few years since
at Chiloe, during a slight earthquake, and created much causeless
alarm.  In the course of the evening there were many weaker shocks,
which seemed to produce in the harbour the most complicated currents,
and some of great strength.


March 4th.--We entered the harbour of Concepcion.  While the ship was
beating up to the anchorage, I landed on the island of Quiriquina.  The
mayor-domo of the estate quickly rode down to tell me the terrible news
of the great earthquake of the 20th:--"That not a house in Concepcion
or Talcahuano (the port) was standing; that seventy villages were
destroyed; and that a great wave had almost washed away the ruins of
Talcahuano." Of this latter statement I soon saw abundant proofs--the
whole coast being strewed over with timber and furniture as if a
thousand ships had been wrecked.  Besides chairs, tables, book-shelves,
etc., in great numbers, there were several roofs of cottages, which had
been transported almost whole.  The storehouses at Talcahuano had been
burst open, and great bags of cotton, yerba, and other valuable
merchandise were scattered on the shore. During my walk round the
island, I observed that numerous fragments of rock, which, from the
marine productions adhering to them, must recently have been lying in
deep water, had been cast up high on the beach; one of these was six
feet long, three broad, and two thick.

The island itself as plainly showed the overwhelming power of the
earthquake, as the beach did that of the consequent great wave.  The
ground in many parts was fissured in north and south lines, perhaps
caused by the yielding of the parallel and steep sides of this narrow
island.  Some of the fissures near the cliffs were a yard wide.  Many
enormous masses had already fallen on the beach; and the inhabitants
thought that when the rains commenced far greater slips would happen.
The effect of the vibration on the hard primary slate, which composes
the foundation of the island, was still more curious: the superficial
parts of some narrow ridges were as completely shivered as if they had
been blasted by gunpowder. This effect, which was rendered conspicuous
by the fresh fractures and displaced soil, must be confined to near the
surface, for otherwise there would not exist a block of solid rock
throughout Chile; nor is this improbable, as it is known that the
surface of a vibrating body is affected differently from the central
part.  It is, perhaps, owing to this same reason, that earthquakes do
not cause quite such terrific havoc within deep mines as would be
expected.  I believe this convulsion has been more effectual in
lessening the size of the island of Quiriquina, than the ordinary
wear-and-tear of the sea and weather during the course of a whole
century.

The next day I landed at Talcahuano, and afterwards rode to Concepcion.
Both towns presented the most awful yet interesting spectacle I ever
beheld.  To a person who had formerly know them, it possibly might have
been still more impressive; for the ruins were so mingled together, and
the whole scene possessed so little the air of a habitable place, that
it was scarcely possible to imagine its former condition. The
earthquake commenced at half-past eleven o'clock in the forenoon.  If
it had happened in the middle of the night, the greater number of the
inhabitants (which in this one province must amount to many thousands)
must have perished, instead of less than a hundred: as it was, the
invariable practice of running out of doors at the first trembling of
the ground, alone saved them.  In Concepcion each house, or row of
houses, stood by itself, a heap or line of ruins; but in Talcahuano,
owing to the great wave, little more than one layer of bricks, tiles,
and timber with here and there part of a wall left standing, could be
distinguished.  From this circumstance Concepcion, although not so
completely desolated, was a more terrible, and if I may so call it,
picturesque sight. The first shock was very sudden.  The mayor-domo at
Quiriquina told me, that the first notice he received of it, was
finding both the horse he rode and himself, rolling together on the
ground.  Rising up, he was again thrown down.  He also told me that
some cows which were standing on the steep side of the island were
rolled into the sea.  The great wave caused the destruction of many
cattle; on one low island near the head of the bay, seventy animals
were washed off and drowned.  It is generally thought that this has
been the worst earthquake ever recorded in Chile; but as the very
severe ones occur only after long intervals, this cannot easily be
known; nor indeed would a much worse shock have made any difference,
for the ruin was now complete.  Innumerable small tremblings followed
the great earthquake, and within the first twelve days no less than
three hundred were counted.

After viewing Concepcion, I cannot understand how the greater number of
inhabitants escaped unhurt.  The houses in many parts fell outwards;
thus forming in the middle of the streets little hillocks of brickwork
and rubbish.  Mr. Rouse, the English consul, told us that he was at
breakfast when the first movement warned him to run out.  He had
scarcely reached the middle of the courtyard, when one side of his
house came thundering down.  He retained presence of mind to remember,
that if he once got on the top of that part which had already fallen,
he would be safe.  Not being able from the motion of the ground to
stand, he crawled up on his hands and knees; and no sooner had he
ascended this little eminence, than the other side of the house fell
in, the great beams sweeping close in front of his head.  With his eyes
blinded, and his mouth choked with the cloud of dust which darkened the
sky, at last he gained the street.  As shock succeeded shock, at the
interval of a few minutes, no one dared approach the shattered ruins,
and no one knew whether his dearest friends and relations were not
perishing from the want of help.  Those who had saved any property were
obliged to keep a constant watch, for thieves prowled about, and at
each little trembling of the ground, with one hand they beat their
breasts and cried "Misericordia!" and then with the other filched what
they could from the ruins.  The thatched roofs fell over the fires, and
flames burst forth in all parts.  Hundreds knew themselves ruined, and
few had the means of providing food for the day.

Earthquakes alone are sufficient to destroy the prosperity of any
country.  If beneath England the now inert subterranean forces should
exert those powers, which most assuredly in former geological ages they
have exerted, how completely would the entire condition of the country
be changed! What would become of the lofty houses, thickly packed
cities, great manufactories, the beautiful public and private edifices?
If the new period of disturbance were first to commence by some great
earthquake in the dead of the night, how terrific would be the carnage!
England would at once be bankrupt; all papers, records, and accounts
would from that moment be lost.  Government being unable to collect the
taxes, and failing to maintain its authority, the hand of violence and
rapine would remain uncontrolled.  In every large town famine would go
forth, pestilence and death following in its train.

Shortly after the shock, a great wave was seen from the distance of
three or four miles, approaching in the middle of the bay with a smooth
outline; but along the shore it tore up cottages and trees, as it swept
onwards with irresistible force.  At the head of the bay it broke in a
fearful line of white breakers, which rushed up to a height of 23
vertical feet above the highest spring-tides.  Their force must have
been prodigious; for at the Fort a cannon with its carriage, estimated
at four tons in weight, was moved 15 feet inwards. A schooner was left
in the midst of the ruins, 200 yards from the beach.  The first wave
was followed by two others, which in their retreat carried away a vast
wreck of floating objects.  In one part of the bay, a ship was pitched
high and dry on shore, was carried off, again driven on shore, and
again carried off.  In another part, two large vessels anchored near
together were whirled about, and their cables were thrice wound round
each other; though anchored at a depth of 36 feet, they were for some
minutes aground.  The great wave must have travelled slowly, for the
inhabitants of Talcahuano had time to run up the hills behind the town;
and some sailors pulled out seaward, trusting successfully to their
boat riding securely over the swell, if they could reach it before it
broke.  One old woman with a little boy, four or five years old, ran
into a boat, but there was nobody to row it out: the boat was
consequently dashed against an anchor and cut in twain; the old woman
was drowned, but the child was picked up some hours afterwards clinging
to the wreck. Pools of salt-water were still standing amidst the ruins
of the houses, and children, making boats with old tables and chairs,
appeared as happy as their parents were miserable. It was, however,
exceedingly interesting to observe, how much more active and cheerful
all appeared than could have been expected.  It was remarked with much
truth, that from the destruction being universal, no one individual was
humbled more than another, or could suspect his friends of
coldness--that most grievous result of the loss of wealth.  Mr. Rouse,
and a large party whom he kindly took under his protection, lived for
the first week in a garden beneath some apple-trees. At first they were
as merry as if it had been a picnic; but soon afterwards heavy rain
caused much discomfort, for they were absolutely without shelter.

In Captain Fitz Roy's excellent account of the earthquake, it is said
that two explosions, one like a column of smoke and another like the
blowing of a great whale, were seen in the bay.  The water also
appeared everywhere to be boiling; and it "became black, and exhaled a
most disagreeable sulphureous smell." These latter circumstances were
observed in the Bay of Valparaiso during the earthquake of 1822; they
may, I think, be accounted for, by the disturbance of the mud at the
bottom of the sea containing organic matter in decay.  In the Bay of
Callao, during a calm day, I noticed, that as the ship dragged her
cable over the bottom, its course was marked by a line of bubbles.  The
lower orders in Talcahuano thought that the earthquake was caused by
some old Indian women, who two years ago, being offended, stopped the
volcano of Antuco.  This silly belief is curious, because it shows that
experience has taught them to observe, that there exists a relation
between the suppressed action of the volcanos, and the trembling of the
ground.  It was necessary to apply the witchcraft to the point where
their perception of cause and effect failed; and this was the closing
of the volcanic vent. This belief is the more singular in this
particular instance, because, according to Captain Fitz Roy, there is
reason to believe that Antuco was noways affected.

The town of Concepcion was built in the usual Spanish fashion, with all
the streets running at right angles to each other; one set ranging S.W.
by W., and the other set N.W. by N.  The walls in the former direction
certainly stood better than those in the latter; the greater number of
the masses of brickwork were thrown down towards the N.E. Both these
circumstances perfectly agree with the general idea, of the undulations
having come from the S.W., in which quarter subterranean noises were
also heard; for it is evident that the walls running S.W. and N.E.
which presented their ends to the point whence the undulations came,
would be much less likely to fall than those walls which, running N.W.
and S.E., must in their whole lengths have been at the same instant
thrown out of the perpendicular; for the undulations, coming from the
S.W., must have extended in N.W. and S.E. waves, as they passed under
the foundations.  This may be illustrated by placing books edgeways on
a carpet, and then, after the manner suggested by Michell, imitating
the undulations of an earthquake: it will be found that they fall with
more or less readiness, according as their direction more or less
nearly coincides with the line of the waves.  The fissures in the
ground generally, though not uniformly, extended in a S.E. and N.W.
direction, and therefore corresponded to the lines of undulation or of
principal flexure.  Bearing in mind all these circumstances, which so
clearly point to the S.W. as the chief focus of disturbance, it is a
very interesting fact that the island of S. Maria, situated in that
quarter, was, during the general uplifting of the land, raised to
nearly three times the height of any other part of the coast.

The different resistance offered by the walls, according to their
direction, was well exemplified in the case of the Cathedral.  The side
which fronted the N.E. presented a grand pile of ruins, in the midst of
which door-cases and masses of timber stood up, as if floating in a
stream.  Some of the angular blocks of brickwork were of great
dimensions; and they were rolled to a distance on the level plaza, like
fragments of rock at the base of some high mountain.  The side walls
(running S.W. and N.E.), though exceedingly fractured, yet remained
standing; but the vast buttresses (at right angles to them, and
therefore parallel to the walls that fell) were in many cases cut clean
off, as if by a chisel, and hurled to the ground.  Some square
ornaments on the coping of these same walls, were moved by the
earthquake into a diagonal position.  A similar circumstance was
observed after an earthquake at Valparaiso, Calabria, and other places,
including some of the ancient Greek temples. [1] This twisting
displacement, at first appears to indicate a vorticose movement beneath
each point thus affected; but this is highly improbable.  May it not be
caused by a tendency in each stone to arrange itself in some particular
position, with respect to the lines of vibration,--in a manner somewhat
similar to pins on a sheet of paper when shaken?  Generally speaking,
arched doorways or windows stood much better than any other part of the
buildings.  Nevertheless, a poor lame old man, who had been in the
habit, during trifling shocks, of crawling to a certain doorway, was
this time crushed to pieces.

I have not attempted to give any detailed description of the appearance
of Concepcion, for I feel that it is quite impossible to convey the
mingled feelings which I experienced. Several of the officers visited
it before me, but their strongest language failed to give a just idea
of the scene of desolation.  It is a bitter and humiliating thing to
see works, which have cost man so much time and labour, overthrown in
one minute; yet compassion for the inhabitants was almost instantly
banished, by the surprise in seeing a state of things produced in a
moment of time, which one was accustomed to attribute to a succession
of ages.  In my opinion, we have scarcely beheld, since leaving
England, any sight so deeply interesting.

In almost every severe earthquake, the neighbouring waters of the sea
are said to have been greatly agitated.  The disturbance seems
generally, as in the case of Concepcion, to have been of two kinds:
first, at the instant of the shock, the water swells high up on the
beach with a gentle motion, and then as quietly retreats; secondly,
some time afterwards, the whole body of the sea retires from the coast,
and then returns in waves of overwhelming force.  The first movement
seems to be an immediate consequence of the earthquake affecting
differently a fluid and a solid, so that their respective levels are
slightly deranged: but the second case is a far more important
phenomenon.  During most earthquakes, and especially during those on
the west coast of America, it is certain that the first great movement
of the waters has been a retirement.  Some authors have attempted to
explain this, by supposing that the water retains its level, whilst the
land oscillates upwards; but surely the water close to the land, even
on a rather steep coast, would partake of the motion of the bottom:
moreover, as urged by Mr. Lyell, similar movements of the sea have
occurred at islands far distant from the chief line of disturbance, as
was the case with Juan Fernandez during this earthquake, and with
Madeira during the famous Lisbon shock.  I suspect (but the subject is
a very obscure one) that a wave, however produced, first draws the
water from the shore, on which it is advancing to break: I have
observed that this happens with the little waves from the paddles of a
steam-boat.  It is remarkable that whilst Talcahuano and Callao (near
Lima), both situated at the head of large shallow bays, have suffered
during every severe earthquake from great waves, Valparaiso, seated
close to the edge of profoundly deep water, has never been overwhelmed,
though so often shaken by the severest shocks.  From the great wave not
immediately following the earthquake, but sometimes after the interval
of even half an hour, and from distant islands being affected similarly
with the coasts near the focus of the disturbance, it appears that the
wave first rises in the offing; and as this is of general occurrence,
the cause must be general: I suspect we must look to the line, where
the less disturbed waters of the deep ocean join the water nearer the
coast, which has partaken of the movements of the land, as the place
where the great wave is first generated; it would also appear that the
wave is larger or smaller, according to the extent of shoal water which
has been agitated together with the bottom on which it rested.


The most remarkable effect of this earthquake was the permanent
elevation of the land, it would probably be far more correct to speak
of it as the cause.  There can be no doubt that the land round the Bay
of Concepcion was upraised two or three feet; but it deserves notice,
that owing to the wave having obliterated the old lines of tidal action
on the sloping sandy shores, I could discover no evidence of this fact,
except in the united testimony of the inhabitants, that one little
rocky shoal, now exposed, was formerly covered with water.  At the
island of S. Maria (about thirty miles distant) the elevation was
greater; on one part, Captain Fitz Roy founds beds of putrid
mussel-shells _still adhering to the rocks_, ten feet above high-water
mark: the inhabitants had formerly dived at lower-water spring-tides
for these shells. The elevation of this province is particularly
interesting, from its having been the theatre of several other violent
earthquakes, and from the vast numbers of sea-shells scattered over the
land, up to a height of certainly 600, and I believe, of 1000 feet.  At
Valparaiso, as I have remarked, similar shells are found at the height
of 1300 feet: it is hardly possible to doubt that this great elevation
has been effected by successive small uprisings, such as that which
accompanied or caused the earthquake of this year, and likewise by an
insensibly slow rise, which is certainly in progress on some parts of
this coast.

The island of Juan Fernandez, 360 miles to the N.E., was, at the time
of the great shock of the 20th, violently shaken, so that the trees
beat against each other, and a volcano burst forth under water close to
the shore: these facts are remarkable because this island, during the
earthquake of 1751, was then also affected more violently than other
places at an equal distance from Concepcion, and this seems to show
some subterranean connection between these two points.  Chiloe, about
340 miles southward of Concepcion, appears to have been shaken more
strongly than the intermediate district of Valdivia, where the volcano
of Villarica was noways affected, whilst in the Cordillera in front of
Chiloe, two of the volcanos burst-forth at the same instant in violent
action.  These two volcanos, and some neighbouring ones, continued for
a long time in eruption, and ten months afterwards were again
influenced by an earthquake at Concepcion.  Some men, cutting wood near
the base of one of these volcanos, did not perceive the shock of the
20th, although the whole surrounding Province was then trembling; here
we have an eruption relieving and taking the place of an earthquake, as
would have happened at Concepcion, according to the belief of the lower
orders, if the volcano at Antuco had not been closed by witchcraft. Two
years and three-quarters afterwards, Valdivia and Chiloe were again
shaken, more violently than on the 20th, and an island in the Chonos
Archipelago was permanently elevated more than eight feet. It will give
a better idea of the scale of these phenomena, if (as in the case of
the glaciers) we suppose them to have taken place at corresponding
distances in Europe:--then would the land from the North Sea to the
Mediterranean have been violently shaken, and at the same instant of
time a large tract of the eastern coast of England would have been
permanently elevated, together with some outlying islands,--a train of
volcanos on the coast of Holland would have burst forth in action, and
an eruption taken place at the bottom of the sea, near the northern
extremity of Ireland--and lastly, the ancient vents of Auvergne,
Cantal, and Mont d'Or would each have sent up to the sky a dark column
of smoke, and have long remained in fierce action.  Two years and
three-quarters afterwards, France, from its centre to the English
Channel, would have been again desolated by an earthquake and an island
permanently upraised in the Mediterranean.

The space, from under which volcanic matter on the 20th was actually
erupted, is 720 miles in one line, and 400 miles in another line at
right angles to the first: hence, in all probability, a subterranean
lake of lava is here stretched out, of nearly double the area of the
Black Sea.  From the intimate and complicated manner in which the
elevatory and eruptive forces were shown to be connected during this
train of phenomena, we may confidently come to the conclusion, that the
forces which slowly and by little starts uplift continents, and those
which at successive periods pour forth volcanic matter from open
orifices, are identical.  From many reasons, I believe that the
frequent quakings of the earth on this line of coast are caused by the
rending of the strata, necessarily consequent on the tension of the
land when upraised, and their injection by fluidified rock.  This
rending and injection would, if repeated often enough (and we know that
earthquakes repeatedly affect the same areas in the same manner), form
a chain of hills;--and the linear island of S. Mary, which was upraised
thrice the height of the neighbouring country, seems to be undergoing
this process.  I believe that the solid axis of a mountain, differs in
its manner of formation from a volcanic hill, only in the molten stone
having been repeatedly injected, instead of having been repeatedly
ejected.  Moreover, I believe that it is impossible to explain the
structure of great mountain-chains, such as that of the Cordillera,
were the strata, capping the injected axis of plutonic rock, have been
thrown on their edges along several parallel and neighbouring lines of
elevation, except on this view of the rock of the axis having been
repeatedly injected, after intervals sufficiently long to allow the
upper parts or wedges to cool and become solid;--for if the strata had
been thrown into their present highly inclined, vertical, and even
inverted positions, by a single blow, the very bowels of the earth
would have gushed out; and instead of beholding abrupt mountain-axes of
rock solidified under great pressure, deluges of lava would have flowed
out at innumerable points on every line of elevation. [2]

[1] M. Arago in L'Institut, 1839, p. 337. See also Miers's Chile, vol.
i. p. 392; also Lyell's Principles of Geology, chap. xv., book ii.

[2] For a full account of the volcanic phenomena which accompanied the
earthquake of the 20th, and for the conclusions deducible from them, I
must refer to Volume V. of the Geological Transactions.



CHAPTER XV

PASSAGE OF THE CORDILLERA

Valparaiso--Portillo Pass--Sagacity of Mules--Mountain-torrents--Mines,
how discovered--Proofs of the gradual Elevation of the
Cordillera--Effect of Snow on Rocks--Geological Structure of the two
main Ranges, their distinct Origin and Upheaval--Great Subsidence--Red
Snow--Winds--Pinnacles of Snow--Dry and clear
Atmosphere--Electricity--Pampas--Zoology of the opposite Side of the
Andes--Locusts--Great Bugs--Mendoza--Uspallata Pass--Silicified Trees
buried as they grew--Incas Bridge--Badness of the Passes
exaggerated--Cumbre--Casuchas--Valparaiso.


MARCH 7th, 1835.--We stayed three days at Concepcion, and then sailed
for Valparaiso.  The wind being northerly, we only reached the mouth of
the harbour of Concepcion before it was dark.  Being very near the
land, and a fog coming on, the anchor was dropped. Presently a large
American whaler appeared alongside of us; and we heard the Yankee
swearing at his men to keep quiet, whilst he listened for the breakers.
Captain Fitz Roy hailed him, in a loud clear voice, to anchor where he
then was.  The poor man must have thought the voice came from the
shore: such a Babel of cries issued at once from the ship--every one
hallooing out, "Let go the anchor! veer cable! shorten sail!" It was
the most laughable thing I ever heard.  If the ship's crew had been all
captains, and no men, there could not have been a greater uproar of
orders.  We afterwards found that the mate stuttered: I suppose all
hands were assisting him in giving his orders.

On the 11th we anchored at Valparaiso, and two days afterwards I set
out to cross the Cordillera.  I proceeded to Santiago, where Mr.
Caldcleugh most kindly assisted me in every possible way in making the
little preparations which were necessary.  In this part of Chile there
are two passes across the Andes to Mendoza: the one most commonly used,
namely, that of Aconcagua or Uspallata--is situated some way to the
north; the other, called the Portillo, is to the south, and nearer, but
more lofty and dangerous.

March 18th.--We set out for the Portillo pass.  Leaving Santiago we
crossed the wide burnt-up plain on which that city stands, and in the
afternoon arrived at the Maypu, one of the principal rivers in Chile.
The valley, at the point where it enters the first Cordillera, is
bounded on each side by lofty barren mountains; and although not broad,
it is very fertile.  Numerous cottages were surrounded by vines, and by
orchards of apple, nectarine, and peach-trees--their boughs breaking
with the weight of the beautiful ripe fruit.  In the evening we passed
the custom-house, where our luggage was examined.  The frontier of
Chile is better guarded by the Cordillera, than by the waters of the
sea.  There are very few valleys which lead to the central ranges, and
the mountains are quite impassable in other parts by beasts of burden.
The custom-house officers were very civil, which was perhaps partly
owing to the passport which the President of the Republic had given me;
but I must express my admiration at the natural politeness of almost
every Chileno.  In this instance, the contrast with the same class of
men in most other countries was strongly marked.  I may mention an
anecdote with which I was at the time much pleased: we met near Mendoza
a little and very fat negress, riding astride on a mule.  She had a
_goitre_ so enormous that it was scarcely possible to avoid gazing at
her for a moment; but my two companions almost instantly, by way of
apology, made the common salute of the country by taking off their
hats.  Where would one of the lower or higher classes in Europe, have
shown such feeling politeness to a poor and miserable object of a
degraded race?

At night we slept at a cottage.  Our manner of travelling was
delightfully independent.  In the inhabited parts we bought a little
firewood, hired pasture for the animals, and bivouacked in the corner
of the same field with them.  Carrying an iron pot, we cooked and ate
our supper under a cloudless sky, and knew no trouble.  My companions
were Mariano Gonzales, who had formerly accompanied me in Chile, and an
"arriero," with his ten mules and a "madrina." The madrina (or
godmother) is a most important personage:

She is an old steady mare, with a little bell round her neck; and
wherever she goes, the mules, like good children, follow her.  The
affection of these animals for their madrinas saves infinite trouble.
If several large troops are turned into one field to graze, in the
morning the muleteers have only to lead the madrinas a little apart,
and tinkle their bells; although there may be two or three hundred
together, each mule immediately knows the bell of its own madrina, and
comes to her.  It is nearly impossible to lose an old mule; for if
detained for several hours by force, she will, by the power of smell,
like a dog, track out her companions, or rather the madrina, for,
according to the muleteer, she is the chief object of affection.  The
feeling, however, is not of an individual nature; for I believe I am
right in saying that any animal with a bell will serve as a madrina. In
a troop each animal carries on a level road, a cargo weighing 416
pounds (more than 29 stone), but in a mountainous country 100 pounds
less; yet with what delicate slim limbs, without any proportional bulk
of muscle, these animals support so great a burden!  The mule always
appears to me a most surprising animal.  That a hybrid should possess
more reason, memory, obstinacy, social affection, powers of muscular
endurance, and length of life, than either of its parents, seems to
indicate that art has here outdone nature.  Of our ten animals, six
were intended for riding, and four for carrying cargoes, each taking
turn about.  We carried a good deal of food in case we should be snowed
up, as the season was rather late for passing the Portillo.

March 19th.--We rode during this day to the last, and therefore most
elevated, house in the valley.  The number of inhabitants became
scanty; but wherever water could be brought on the land, it was very
fertile.  All the main valleys in the Cordillera are characterized by
having, on both sides, a fringe or terrace of shingle and sand, rudely
stratified, and generally of considerable thickness.  These fringes
evidently once extended across the valleys and were united; and the
bottoms of the valleys in northern Chile, where there are no streams,
are thus smoothly filled up.  On these fringes the roads are generally
carried, for their surfaces are even, and they rise, with a very gentle
slope up the valleys: hence, also, they are easily cultivated by
irrigation.  They may be traced up to a height of between 7000 and 9000
feet, where they become hidden by the irregular piles of debris.  At
the lower end or mouths of the valleys, they are continuously united to
those land-locked plains (also formed of shingle) at the foot of the
main Cordillera, which I have described in a former chapter as
characteristic of the scenery of Chile, and which were undoubtedly
deposited when the sea penetrated Chile, as it now does the more
southern coasts.  No one fact in the geology of South America,
interested me more than these terraces of rudely-stratified shingle.
They precisely resemble in composition the matter which the torrents in
each valley would deposit, if they were checked in their course by any
cause, such as entering a lake or arm of the sea; but the torrents,
instead of depositing matter, are now steadily at work wearing away
both the solid rock and these alluvial deposits, along the whole line
of every main valley and side valley.  It is impossible here to give
the reasons, but I am convinced that the shingle terraces were
accumulated, during the gradual elevation of the Cordillera, by the
torrents delivering, at successive levels, their detritus on the
beachheads of long narrow arms of the sea, first high up the valleys,
then lower and lower down as the land slowly rose.  If this be so, and
I cannot doubt it, the grand and broken chain of the Cordillera,
instead of having been suddenly thrown up, as was till lately the
universal, and still is the common opinion of geologists, has been
slowly upheaved in mass, in the same gradual manner as the coasts of
the Atlantic and Pacific have risen within the recent period.  A
multitude of facts in the structure of the Cordillera, on this view
receive a simple explanation.

The rivers which flow in these valleys ought rather to be called
mountain-torrents.  Their inclination is very great, and their water
the colour of mud.  The roar which the Maypu made, as it rushed over
the great rounded fragments, was like that of the sea.  Amidst the din
of rushing waters, the noise from the stones, as they rattled one over
another, was most distinctly audible even from a distance.  This
rattling noise, night and day, may be heard along the whole course of
the torrent.  The sound spoke eloquently to the geologist; the
thousands and thousands of stones, which, striking against each other,
made the one dull uniform sound, were all hurrying in one direction. It
was like thinking on time, where the minute that now glides past is
irrevocable. So was it with these stones; the ocean is their eternity,
and each note of that wild music told of one more step towards their
destiny.

It is not possible for the mind to comprehend, except by a slow
process, any effect which is produced by a cause repeated so often,
that the multiplier itself conveys an idea, not more definite than the
savage implies when he points to the hairs of his head.  As often as I
have seen beds of mud, sand, and shingle, accumulated to the thickness
of many thousand feet, I have felt inclined to exclaim that causes,
such as the present rivers and the present beaches, could never have
ground down and produced such masses.  But, on the other hand, when
listening to the rattling noise of these torrents, and calling to mind
that whole races of animals have passed away from the face of the
earth, and that during this whole period, night and day, these stones
have gone rattling onwards in their course, I have thought to myself,
can any mountains, any continent, withstand such waste?

In this part of the valley, the mountains on each side were from 3000
to 6000 or 8000 feet high, with rounded outlines and steep bare flanks.
The general colour of the rock was dullish purple, and the
stratification very distinct.  If the scenery was not beautiful, it was
remarkable and grand.  We met during the day several herds of cattle,
which men were driving down from the higher valleys in the Cordillera.
This sign of the approaching winter hurried our steps, more than was
convenient for geologizing.  The house where we slept was situated at
the foot of a mountain, on the summit of which are the mines of S.
Pedro de Nolasko.  Sir F. Head marvels how mines have been discovered
in such extraordinary situations, as the bleak summit of the mountain
of S. Pedro de Nolasko.  In the first place, metallic veins in this
country are generally harder than the surrounding strata: hence, during
the gradual wear of the hills, they project above the surface of the
ground.  Secondly, almost every labourer, especially in the northern
parts of Chile, understands something about the appearance of ores.  In
the great mining provinces of Coquimbo and Copiapo, firewood is very
scarce, and men search for it over every hill and dale; and by this
means nearly all the richest mines have there been discovered.
Chanuncillo, from which silver to the value of many hundred thousand
pounds has been raised in the course of a few years, was discovered by
a man who threw a stone at his loaded donkey, and thinking that it was
very heavy, he picked it up, and found it full of pure silver: the vein
occurred at no great distance, standing up like a wedge of metal.  The
miners, also, taking a crowbar with them, often wander on Sundays over
the mountains.  In this south part of Chile, the men who drive cattle
into the Cordillera, and who frequent every ravine where there is a
little pasture, are the usual discoverers.

20th.--As we ascended the valley, the vegetation, with the exception of
a few pretty alpine flowers, became exceedingly scanty, and of
quadrupeds, birds, or insects, scarcely one could be seen.  The lofty
mountains, their summits marked with a few patches of snow, stood well
separated from each other, the valleys being filled up with an immense
thickness of stratified alluvium.  The features in the scenery of the
Andes which struck me most, as contrasted with the other mountain
chains with which I am acquainted, were,--the flat fringes sometimes
expanding into narrow plains on each side of the valleys,--the bright
colours, chiefly red and purple, of the utterly bare and precipitous
hills of porphyry, the grand and continuous wall-like dykes,--the
plainly-divided strata which, where nearly vertical, formed the
picturesque and wild central pinnacles, but where less inclined,
composed the great massive mountains on the outskirts of the
range,--and lastly, the smooth conical piles of fine and brightly
coloured detritus, which sloped up at a high angle from the base of the
mountains, sometimes to a height of more than 2000 feet.

I frequently observed, both in Tierra del Fuego and within the Andes,
that where the rock was covered during the greater part of the year
with snow, it was shivered in a very extraordinary manner into small
angular fragments.  Scoresby [1] has observed the same fact in
Spitzbergen.  The case appears to me rather obscure: for that part of
the mountain which is protected by a mantle of snow, must be less
subject to repeated and great changes of temperature than any other
part.  I have sometimes thought, that the earth and fragments of stone
on the surface, were perhaps less effectually removed by slowly
percolating snow-water [2] than by rain, and therefore that the
appearance of a quicker disintegration of the solid rock under the
snow, was deceptive.  Whatever the cause may be, the quantity of
crumbling stone on the Cordillera is very great.  Occasionally in the
spring, great masses of this detritus slide down the mountains, and
cover the snow-drifts in the valleys, thus forming natural ice-houses.
We rode over one, the height of which was far below the limit of
perpetual snow.

As the evening drew to a close, we reached a singular basin-like plain,
called the Valle del Yeso.  It was covered by a little dry pasture, and
we had the pleasant sight of a herd of cattle amidst the surrounding
rocky deserts.  The valley takes its name of Yeso from a great bed, I
should think at least 2000 feet thick, of white, and in some parts
quite pure, gypsum.  We slept with a party of men, who were employed in
loading mules with this substance, which is used in the manufacture of
wine.  We set out early in the morning (21st), and continued to follow
the course of the river, which had become very small, till we arrived
at the foot of the ridge, that separates the waters flowing into the
Pacific and Atlantic Oceans.  The road, which as yet had been good with
a steady but very gradual ascent, now changed into a steep zigzag track
up the great range, dividing the republics of Chile and Mendoza.

I will here give a very brief sketch of the geology of the several
parallel lines forming the Cordillera.  Of these lines, there are two
considerably higher than the others; namely, on the Chilian side, the
Peuquenes ridge, which, where the road crosses it, is 13,210 feet above
the sea; and the Portillo ridge, on the Mendoza side, which is 14,305
feet.  The lower beds of the Peuquenes ridge, and of the several great
lines to the westward of it, are composed of a vast pile, many thousand
feet in thickness, of porphyries which have flowed as submarine lavas,
alternating with angular and rounded fragments of the same rocks,
thrown out of the submarine craters. These alternating masses are
covered in the central parts, by a great thickness of red sandstone,
conglomerate, and calcareous clay-slate, associated with, and passing
into, prodigious beds of gypsum.  In these upper beds shells are
tolerably frequent; and they belong to about the period of the lower
chalk of Europe.  It is an old story, but not the less wonderful, to
hear of shells which were once crawling on the bottom of the sea, now
standing nearly 14,000 feet above its level.  The lower beds in this
great pile of strata, have been dislocated, baked, crystallized and
almost blended together, through the agency of mountain masses of a
peculiar white soda-granitic rock.

The other main line, namely, that of the Portillo, is of a totally
different formation: it consists chiefly of grand bare pinnacles of a
red potash-granite, which low down on the western flank are covered by
a sandstone, converted by the former heat into a quartz-rock.  On the
quartz, there rest beds of a conglomerate several thousand feet in
thickness, which have been upheaved by the red granite, and dip at an
angle of 45 degs. towards the Peuquenes line.  I was astonished to find
that this conglomerate was partly composed of pebbles, derived from the
rocks, with their fossil shells, of the Peuquenes range; and partly of
red potash-granite, like that of the Portillo.  Hence we must conclude,
that both the Peuquenes and Portillo ranges were partially upheaved and
exposed to wear and tear, when the conglomerate was forming; but as the
beds of the conglomerate have been thrown off at an angle of 45 degs.
by the red Portillo granite (with the underlying sandstone baked by
it), we may feel sure, that the greater part of the injection and
upheaval of the already partially formed Portillo line, took place
after the accumulation of the conglomerate, and long after the
elevation of the Peuquenes ridge.  So that the Portillo, the loftiest
line in this part of the Cordillera, is not so old as the less lofty
line of the Peuquenes.  Evidence derived from an inclined stream of
lava at the eastern base of the Portillo, might be adduced to show,
that it owes part of its great height to elevations of a still later
date.  Looking to its earliest origin, the red granite seems to have
been injected on an ancient pre-existing line of white granite and
mica-slate.  In most parts, perhaps in all parts, of the Cordillera, it
may be concluded that each line has been formed by repeated upheavals
and injections; and that the several parallel lines are of different
ages.  Only thus can we gain time, at all sufficient to explain the
truly astonishing amount of denudation, which these great, though
comparatively with most other ranges recent, mountains have suffered.

Finally, the shells in the Peuquenes or oldest ridge, prove, as before
remarked, that it has been upraised 14,000 feet since a Secondary
period, which in Europe we are accustomed to consider as far from
ancient; but since these shells lived in a moderately deep sea, it can
be shown that the area now occupied by the Cordillera, must have
subsided several thousand feet--in northern Chile as much as 6000
feet--so as to have allowed that amount of submarine strata to have
been heaped on the bed on which the shells lived.  The proof is the
same with that by which it was shown, that at a much later period,
since the tertiary shells of Patagonia lived, there must have been
there a subsidence of several hundred feet, as well as an ensuing
elevation.  Daily it is forced home on the mind of the geologist, that
nothing, not even the wind that blows, is so unstable as the level of
the crust of this earth.

I will make only one other geological remark: although the Portillo
chain is here higher than the Peuquenes, the waters draining the
intermediate valleys, have burst through it.  The same fact, on a
grander scale, has been remarked in the eastern and loftiest line of
the Bolivian Cordillera, through which the rivers pass: analogous facts
have also been observed in other quarters of the world.  On the
supposition of the subsequent and gradual elevation of the Portillo
line, this can be understood; for a chain of islets would at first
appear, and, as these were lifted up, the tides would be always wearing
deeper and broader channels between them. At the present day, even in
the most retired Sounds on the coast of Tierra del Fuego, the currents
in the transverse breaks which connect the longitudinal channels, are
very strong, so that in one transverse channel even a small vessel
under sail was whirled round and round.


About noon we began the tedious ascent of the Peuquenes ridge, and then
for the first time experienced some little difficulty in our
respiration.  The mules would halt every fifty yards, and after resting
for a few seconds the poor willing animals started of their own accord
again.  The short breathing from the rarefied atmosphere is called by
the Chilenos "puna;" and they have most ridiculous notions concerning
its origin.  Some say "all the waters here have puna;" others that
"where there is snow there is puna;"--and this no doubt is true.  The
only sensation I experienced was a slight tightness across the head and
chest, like that felt on leaving a warm room and running quickly in
frosty weather.  There was some imagination even in this; for upon
finding fossil shells on the highest ridge, I entirely forgot the puna
in my delight.  Certainly the exertion of walking was extremely great,
and the respiration became deep and laborious: I am told that in Potosi
(about 13,000 feet above the sea) strangers do not become thoroughly
accustomed to the atmosphere for an entire year.  The inhabitants all
recommend onions for the puna; as this vegetable has sometimes been
given in Europe for pectoral complaints, it may possibly be of real
service:--for my part I found nothing so good as the fossil shells!

When about half-way up we met a large party with seventy loaded mules.
It was interesting to hear the wild cries of the muleteers, and to
watch the long descending string of the animals; they appeared so
diminutive, there being nothing but the black mountains with which they
could be compared.  When near the summit, the wind, as generally
happens, was impetuous and extremely cold.  On each side of the ridge,
we had to pass over broad bands of perpetual snow, which were now soon
to be covered by a fresh layer. When we reached the crest and looked
backwards, a glorious view was presented.  The atmosphere resplendently
clear; the sky an intense blue; the profound valleys; the wild broken
forms: the heaps of ruins, piled up during the lapse of ages; the
bright-coloured rocks, contrasted with the quiet mountains of snow, all
these together produced a scene no one could have imagined.  Neither
plant nor bird, excepting a few condors wheeling around the higher
pinnacles, distracted my attention from the inanimate mass.  I felt
glad that I was alone: it was like watching a thunderstorm, or hearing
in full orchestra a chorus of the Messiah.

On several patches of the snow I found the Protococcus nivalis, or red
snow, so well known from the accounts of Arctic navigators.  My
attention was called to it, by observing the footsteps of the mules
stained a pale red, as if their hoofs had been slightly bloody.  I at
first thought that it was owing to dust blown from the surrounding
mountains of red porphyry; for from the magnifying power of the
crystals of snow, the groups of these microscopical plants appeared
like coarse particles.  The snow was coloured only where it had thawed
very rapidly, or had been accidentally crushed. A little rubbed on
paper gave it a faint rose tinge mingled with a little brick-red.  I
afterwards scraped some off the paper, and found that it consisted of
groups of little spheres in colourless cases, each of the thousandth
part of an inch in diameter.

The wind on the crest of the Peuquenes, as just remarked, is generally
impetuous and very cold: it is said [3] to blow steadily from the
westward or Pacific side.  As the observations have been chiefly made
in summer, this wind must be an upper and return current.  The Peak of
Teneriffe, with a less elevation, and situated in lat. 28 degs., in
like manner falls within an upper return stream.  At first it appears
rather surprising, that the trade-wind along the northern parts of
Chile and on the coast of Peru, should blow in so very southerly a
direction as it does; but when we reflect that the Cordillera, running
in a north and south line, intercepts, like a great wall, the entire
depth of the lower atmospheric current, we can easily see that the
trade-wind must be drawn northward, following the line of mountains,
towards the equatorial regions, and thus lose part of that easterly
movement which it otherwise would have gained from the earth's
rotation.  At Mendoza, on the eastern foot of the Andes, the climate is
said to be subject to long calms, and to frequent though false
appearances of gathering rain-storms: we may imagine that the wind,
which coming from the eastward is thus banked up by the line of
mountains, would become stagnant and irregular in its movements.

Having crossed the Peuquenes, we descended into a mountainous country,
intermediate between the two main ranges, and then took up our quarters
for the night.  We were now in the republic of Mendoza.  The elevation
was probably not under 11,000 feet, and the vegetation in consequence
exceedingly scanty.  The root of a small scrubby plant served as fuel,
but it made a miserable fire, and the wind was piercingly cold.  Being
quite tired with my days work, I made up my bed as quickly as I could,
and went to sleep. About midnight I observed the sky became suddenly
clouded: I awakened the arriero to know if there was any danger of bad
weather; but he said that without thunder and lightning there was no
risk of a heavy snow-storm.  The peril is imminent, and the difficulty
of subsequent escape great, to any one overtaken by bad weather between
the two ranges. A certain cave offers the only place of refuge: Mr.
Caldcleugh, who crossed on this same day of the month, was detained
there for some time by a heavy fall of snow.  Casuchas, or houses of
refuge, have not been built in this pass as in that of Uspallata, and,
therefore, during the autumn, the Portillo is little frequented.  I may
here remark that within the main Cordillera rain never falls, for
during the summer the sky is cloudless, and in winter snow-storms alone
occur.

At the place where we slept water necessarily boiled, from the
diminished pressure of the atmosphere, at a lower temperature than it
does in a less lofty country; the case being the converse of that of a
Papin's digester.  Hence the potatoes, after remaining for some hours
in the boiling water, were nearly as hard as ever.  The pot was left on
the fire all night, and next morning it was boiled again, but yet the
potatoes were not cooked.  I found out this, by overhearing my two
companions discussing the cause, they had come to the simple
conclusion, "that the cursed pot [which was a new one] did not choose
to boil potatoes."

March  22nd.--After eating our potatoless breakfast, we travelled
across the intermediate tract to the foot of the Portillo range.  In
the middle of summer cattle are brought up here to graze; but they had
now all been removed: even the greater number of the Guanacos had
decamped, knowing well that if overtaken here by a snow-storm, they
would be caught in a trap.  We had a fine view of a mass of mountains
called Tupungato, the whole clothed with unbroken snow, in the midst of
which there was a blue patch, no doubt a glacier;--a circumstance of
rare occurrence in these mountains.  Now commenced a heavy and long
climb, similar to that of the Peuquenes.  Bold conical hills of red
granite rose on each hand; in the valleys there were several broad
fields of perpetual snow.  These frozen masses, during the process of
thawing, had in some parts been converted into pinnacles or columns,
[4] which, as they were high and close together, made it difficult for
the cargo mules to pass. On one of these columns of ice, a frozen horse
was sticking as on a pedestal, but with its hind legs straight up in
the air.  The animal, I suppose, must have fallen with its head
downward into a hole, when the snow was continuous, and afterwards the
surrounding parts must have been removed by the thaw.

When nearly on the crest of the Portillo, we were enveloped in a
falling cloud of minute frozen spicula.  This was very unfortunate, as
it continued the whole day, and quite intercepted our view.  The pass
takes its name of Portillo, from a narrow cleft or doorway on the
highest ridge, through which the road passes.  From this point, on a
clear day, those vast plains which uninterruptedly extend to the
Atlantic Ocean can be seen.  We descended to the upper limit of
vegetation, and found good quarters for the night under the shelter of
some large fragments of rock.  We met here some passengers, who made
anxious inquiries about the state of the road.  Shortly after it was
dark the clouds suddenly cleared away, and the effect was quite
magical.  The great mountains, bright with the full moon, seemed
impending over us on all sides, as over a deep crevice: one morning,
very early, I witnessed the same striking effect.  As soon as the
clouds were dispersed it froze severely; but as there was no wind, we
slept very comfortably.

The increased brilliancy of the moon and stars at this elevation, owing
to the perfect transparency of the atmosphere, was very remarkable.
Travelers having observed the difficulty of judging heights and
distances amidst lofty mountains, have generally attributed it to the
absence of objects of comparison.  It appears to me, that it is fully
as much owing to the transparency of the air confounding objects at
different distances, and likewise partly to the novelty of an unusual
degree of fatigue arising from a little exertion,--habit being thus
opposed to the evidence of the senses.  I am sure that this extreme
clearness of the air gives a peculiar character to the landscape, all
objects appearing to be brought nearly into one plane, as in a drawing
or panorama.  The transparency is, I presume, owing to the equable and
high state of atmospheric dryness.  This dryness was shown by the
manner in which woodwork shrank (as I soon found by the trouble my
geological hammer gave me); by articles of food, such as bread and
sugar, becoming extremely hard; and by the preservation of the skin and
parts of the flesh of the beasts, which had perished on the road.  To
the same cause we must attribute the singular facility with which
electricity is excited.  My flannel waistcoat, when rubbed in the dark,
appeared as if it had been washed with phosphorus,--every hair on a
dog's back crackled;--even the linen sheets, and leathern straps of the
saddle, when handled, emitted sparks.

March 23rd.--The descent on the eastern side of the Cordillera is much
shorter or steeper than on the Pacific side; in other words, the
mountains rise more abruptly from the plains than from the alpine
country of Chile.  A level and brilliantly white sea of clouds was
stretched out beneath our feet, shutting out the view of the equally
level Pampas.  We soon entered the band of clouds, and did not again
emerge from it that day.  About noon, finding pasture for the animals
and bushes for firewood at Los Arenales, we stopped for the night. This
was near the uppermost limit of bushes, and the elevation, I suppose,
was between seven and eight thousand feet.

I was much struck with the marked difference between the vegetation of
these eastern valleys and those on the Chilian side: yet the climate,
as well as the kind of soil, is nearly the same, and the difference of
longitude very trifling. The same remark holds good with the
quadrupeds, and in a lesser degree with the birds and insects.  I may
instance the mice, of which I obtained thirteen species on the shores
of the Atlantic, and five on the Pacific, and not one of them is
identical.  We must except all those species, which habitually or
occasionally frequent elevated mountains; and certain birds, which
range as far south as the Strait of Magellan. This fact is in perfect
accordance with the geological history of the Andes; for these
mountains have existed as a great barrier since the present races of
animals have appeared; and therefore, unless we suppose the same
species to have been created in two different places, we ought not to
expect any closer similarity between the organic beings on the opposite
sides of the Andes than on the opposite shores of the ocean.  In both
cases, we must leave out of the question those kinds which have been
able to cross the barrier, whether of solid rock or salt-water. [5]

A great number of the plants and animals were absolutely the same as,
or most closely allied to, those of Patagonia. We here have the agouti,
bizcacha, three species of armadillo, the ostrich, certain kinds of
partridges and other birds, none of which are ever seen in Chile, but
are the characteristic animals of the desert plains of Patagonia.  We
have likewise many of the same (to the eyes of a person who is not a
botanist) thorny stunted bushes, withered grass, and dwarf plants. Even
the black slowly crawling beetles are closely similar, and some, I
believe, on rigorous examination, absolutely identical.  It had always
been to me a subject of regret, that we were unavoidably compelled to
give up the ascent of the S. Cruz river before reaching the mountains:
I always had a latent hope of meeting with some great change in the
features of the country; but I now feel sure, that it would only have
been following the plains of Patagonia up a mountainous ascent.

March  24th.--Early in the morning I climbed up a mountain on one side
of the valley, and enjoyed a far extended view over the Pampas. This
was a spectacle to which I had always looked forward with interest, but
I was disappointed: at the first glance it much resembled a distant
view of the ocean, but in the northern parts many irregularities were
soon distinguishable.  The most striking feature consisted in the
rivers, which, facing the rising sun, glittered like silver threads,
till lost in the immensity of the distance.  At midday we descended the
valley, and reached a hovel, where an officer and three soldiers were
posted to examine passports. One of these men was a thoroughbred Pampas
Indian: he was kept much for the same purpose as a bloodhound, to track
out any person who might pass by secretly, either on foot or horseback.
Some years ago, a passenger endeavoured to escape detection, by making
a long circuit over a neighbouring mountain; but this Indian, having by
chance crossed his track, followed it for the whole day over dry and
very stony hills, till at last he came on his prey hidden in a gully.
We here heard that the silvery clouds, which we had admired from the
bright region above, had poured down torrents of rain.  The valley from
this point gradually opened, and the hills became mere water-worn
hillocks compared to the giants behind: it then expanded into a gently
sloping plain of shingle, covered with low trees and bushes.  This
talus, although appearing narrow, must be nearly ten miles wide before
it blends into the apparently dead level Pampas.  We passed the only
house in this neighbourhood, the Estancia of Chaquaio: and at sunset we
pulled up in the first snug corner, and there bivouacked.

March 25th.--I  was reminded of the Pampas of Buenos Ayres, by seeing
the disk of the rising sun, intersected by an horizon level as that of
the ocean.  During the night a heavy dew fell, a circumstance which we
did not experience within the Cordillera.  The road proceeded for some
distance due east across a low swamp; then meeting the dry plain, it
turned to the north towards Mendoza.  The distance is two very long
days' journey.  Our first day's journey was called fourteen leagues to
Estacado, and the second seventeen to Luxan, near Mendoza.  The whole
distance is over a level desert plain, with not more than two or three
houses.  The sun was exceedingly powerful, and the ride devoid of all
interest.  There is very little water in this "traversia," and in our
second day's journey we found only one little pool. Little water flows
from the mountains, and it soon becomes absorbed by the dry and porous
soil; so that, although we travelled at the distance of only ten or
fifteen miles from the outer range of the Cordillera, we did not cross
a single stream.  In many parts the ground was incrusted with a saline
efflorescence; hence we had the same salt-loving plants which are
common near Bahia Blanca.  The landscape has a uniform character from
the Strait of Magellan, along the whole eastern coast of Patagonia, to
the Rio Colorado; and it appears that the same kind of country extends
inland from this river, in a sweeping line as far as San Luis and
perhaps even further north.  To the eastward of this curved line lies
the basin of the comparatively damp and green plains of Buenos Ayres.
The sterile plains of Mendoza and Patagonia consist of a bed of
shingle, worn smooth and accumulated by the waves of the sea while the
Pampas, covered by thistles, clover, and grass, have been formed by the
ancient estuary mud of the Plata.

After our two days' tedious journey, it was refreshing to see in the
distance the rows of poplars and willows growing round the village and
river of Luxan.  Shortly before we arrived at this place, we observed
to the south a ragged cloud of dark reddish-brown colour.  At first we
thought that it was smoke from some great fire on the plains; but we
soon found that it was a swarm of locusts.  They were flying northward;
and with the aid of a light breeze, they overtook us at a rate of ten
or fifteen miles an hour.  The main body filled the air from a height
of twenty feet, to that, as it appeared, of two or three thousand above
the ground; "and the sound of their wings was as the sound of chariots
of many horses running to battle:" or rather, I should say, like a
strong breeze passing through the rigging of a ship.  The sky, seen
through the advanced guard, appeared like a mezzotinto engraving, but
the main body was impervious to sight; they were not, however, so thick
together, but that they could escape a stick waved backwards and
forwards.  When they alighted, they were more numerous than the leaves
in the field, and the surface became reddish instead of being green:
the swarm having once alighted, the individuals flew from side to side
in all directions.  Locusts are not an uncommon pest in this country:
already during the season, several smaller swarms had come up from the
south, where, as apparently in all other parts of the world, they are
bred in the deserts.  The poor cottagers in vain attempted by lighting
fires, by shouts, and by waving branches to avert the attack.  This
species of locust closely resembles, and perhaps is identical with, the
famous Gryllus migratorius of the East.

We crossed the Luxan, which is a river of considerable size, though its
course towards the sea-coast is very imperfectly known: it is even
doubtful whether, in passing over the plains, it is not evaporated and
lost.  We slept in the village of Luxan, which is a small place
surrounded by gardens, and forms the most southern cultivated district
in the Province of Mendoza; it is five leagues south of the capital. At
night I experienced an attack (for it deserves no less a name) of the
_Benchuca_, a species of Reduvius, the great black bug of the Pampas.
It is most disgusting to feel soft wingless insects, about an inch
long, crawling over one's body.  Before sucking they are quite thin,
but afterwards they become round and bloated with blood, and in this
state are easily crushed.  One which I caught at Iquique, (for they are
found in Chile and Peru,) was very empty.  When placed on a table, and
though surrounded by people, if a finger was presented, the bold insect
would immediately protrude its sucker, make a charge, and if allowed,
draw blood.  No pain was caused by the wound.  It was curious to watch
its body during the act of sucking, as in less than ten minutes it
changed from being as flat as a wafer to a globular form. This one
feast, for which the benchuca was indebted to one of the officers, kept
it fat during four whole months; but, after the first fortnight, it was
quite ready to have another suck.

March 27th.--We rode on to Mendoza.  The country was beautifully
cultivated, and resembled Chile.  This neighbourhood is celebrated for
its fruit; and certainly nothing could appear more flourishing than the
vineyards and the orchards of figs, peaches, and olives.  We bought
water-melons nearly twice as large as a man's head, most deliciously
cool and well-flavoured, for a halfpenny apiece; and for the value of
threepence, half a wheelbarrowful of peaches.  The cultivated and
enclosed part of this province is very small; there is little more than
that which we passed through between Luxan and the capital.  The land,
as in Chile, owes its fertility entirely to artificial irrigation; and
it is really wonderful to observe how extraordinarily productive a
barren traversia is thus rendered.

We stayed the ensuing day in Mendoza.  The prosperity of the place has
much declined of late years.  The inhabitants say "it is good to live
in, but very bad to grow rich in." The lower orders have the lounging,
reckless manners of the Gauchos of the Pampas; and their dress,
riding-gear, and habits of life, are nearly the same.  To my mind the
town had a stupid, forlorn aspect.  Neither the boasted alameda, nor
the scenery, is at all comparable with that of Santiago; but to those
who, coming from Buenos Ayres, have just crossed the unvaried Pampas,
the gardens and orchards must appear delightful.  Sir F. Head, speaking
of the inhabitants, says, "They eat their dinners, and it is so very
hot, they go to sleep--and could they do better?" I quite agree with
Sir F. Head: the happy doom of the Mendozinos is to eat, sleep and be
idle.


March 29th.--We set out on our return to Chile, by the Uspallata pass
situated north of Mendoza.  We had to cross a long and most sterile
traversia of fifteen leagues.  The soil in parts was absolutely bare,
in others covered by numberless dwarf cacti, armed with formidable
spines, and called by the inhabitants "little lions." There were, also,
a few low bushes.  Although the plain is nearly three thousand feet
above the sea, the sun was very powerful; and the heat as well as the
clouds of impalpable dust, rendered the travelling extremely irksome.
Our course during the day lay nearly parallel to the Cordillera, but
gradually approaching them. Before sunset we entered one of the wide
valleys, or rather bays, which open on the plain: this soon narrowed
into a ravine, where a little higher up the house of Villa Vicencio is
situated.  As we had ridden all day without a drop of water, both our
mules and selves were very thirsty, and we looked out anxiously for the
stream which flows down this valley.  It was curious to observe how
gradually the water made its appearance: on the plain the course was
quite dry; by degrees it became a little damper; then puddles of water
appeared; these soon became connected; and at Villa Vicencio there was
a nice little rivulet.

30th.--The solitary hovel which bears the imposing name of Villa
Vicencio, has been mentioned by every traveller who has crossed the
Andes.  I stayed here and at some neighbouring mines during the two
succeeding days.  The geology of the surrounding country is very
curious.  The Uspallata range is separated from the main Cordillera by
a long narrow plain or basin, like those so often mentioned in Chile,
but higher, being six thousand feet above the sea.  This range has
nearly the same geographical position with respect to the Cordillera,
which the gigantic Portillo line has, but it is of a totally different
origin: it consists of various kinds of submarine lava, alternating
with volcanic sandstones and other remarkable sedimentary deposits; the
whole having a very close resemblance to some of the tertiary beds on
the shores of the Pacific.  From this resemblance I expected to find
silicified wood, which is generally characteristic of those formations.
I was gratified in a very extraordinary manner. In the central part of
the range, at an elevation of about seven thousand feet, I observed on
a bare slope some snow-white projecting columns.  These were petrified
trees, eleven being silicified, and from thirty to forty converted into
coarsely-crystallized white calcareous spar.  They were abruptly broken
off, the upright stumps projecting a few feet above the ground.  The
trunks measured from three to five feet each in circumference.  They
stood a little way apart from each other, but the whole formed one
group.  Mr. Robert Brown has been kind enough to examine the wood: he
says it belongs to the fir tribe, partaking of the character of the
Araucarian family, but with some curious points of affinity with the
yew.  The volcanic sandstone in which the trees were embedded, and from
the lower part of which they must have sprung, had accumulated in
successive thin layers around their trunks; and the stone yet retained
the impression of the bark.

It required little geological practice to interpret the marvellous
story which this scene at once unfolded; though I confess I was at
first so much astonished that I could scarcely believe the plainest
evidence.  I saw the spot where a cluster of fine trees once waved
their branches on the shores of the Atlantic, when that ocean (now
driven back 700 miles) came to the foot of the Andes.  I saw that they
had sprung from a volcanic soil which had been raised above the level
of the sea, and that subsequently this dry land, with its upright
trees, had been let down into the depths of the ocean.  In these
depths, the formerly dry land was covered by sedimentary beds, and
these again by enormous streams of submarine lava--one such mass
attaining the thickness of a thousand feet; and these deluges of molten
stone and aqueous deposits five times alternately had been spread out.
The ocean which received such thick masses, must have been profoundly
deep; but again the subterranean forces exerted themselves, and I now
beheld the bed of that ocean, forming a chain of mountains more than
seven thousand feet in height.  Nor had those antagonistic forces been
dormant, which are always at work wearing down the surface of the land;
the great piles of strata had been intersected by many wide valleys,
and the trees now changed into silex, were exposed projecting from the
volcanic soil, now changed into rock, whence formerly, in a green and
budding state, they had raised their lofty heads.  Now, all is utterly
irreclaimable and desert; even the lichen cannot adhere to the stony
casts of former trees.  Vast, and scarcely comprehensible as such
changes must ever appear, yet they have all occurred within a period,
recent when compared with the history of the Cordillera; and the
Cordillera itself is absolutely modern as compared with many of the
fossiliferous strata of Europe and America.

April 1st.--We crossed the Upsallata range, and at night slept at the
custom-house--the only inhabited spot on the plain.  Shortly before
leaving the mountains, there was a very extraordinary view; red,
purple, green, and quite white sedimentary rocks, alternating with
black lavas, were broken up and thrown into all kinds of disorder by
masses of porphyry of every shade of colour, from dark brown to the
brightest lilac.  It was the first view I ever saw, which really
resembled those pretty sections which geologists make of the inside of
the earth.

The next day we crossed the plain, and followed the course of the same
great mountain stream which flows by Luxan. Here it was a furious
torrent, quite impassable, and appeared larger than in the low country,
as was the case with the rivulet of Villa Vicencio.  On the evening of
the succeeding day, we reached the Rio de las Vacas, which is
considered the worst stream in the Cordillera to cross.  As all these
rivers have a rapid and short course, and are formed by the melting of
the snow, the hour of the day makes a considerable difference in their
volume.  In the evening the stream is muddy and full, but about
daybreak it becomes clearer, and much less impetuous.  This we found to
be the case with the Rio Vacas, and in the morning we crossed it with
little difficulty.

The scenery thus far was very uninteresting, compared with that of the
Portillo pass.  Little can be seen beyond the bare walls of the one
grand flat-bottomed valley, which the road follows up to the highest
crest.  The valley and the huge rocky mountains are extremely barren:
during the two previous nights the poor mules had absolutely nothing to
eat, for excepting a few low resinous bushes, scarcely a plant can be
seen.  In the course of this day we crossed some of the worst passes in
the Cordillera, but their danger has been much exaggerated.  I was told
that if I attempted to pass on foot, my head would turn giddy, and that
there was no room to dismount; but I did not see a place where any one
might not have walked over backwards, or got off his mule on either
side.  One of the bad passes, called _las Animas_ (the souls), I had
crossed, and did not find out till a day afterwards, that it was one of
the awful dangers. No doubt there are many parts in which, if the mule
should stumble, the rider would be hurled down a great precipice; but
of this there is little chance.  I dare say, in the spring, the
"laderas," or roads, which each year are formed anew across the piles
of fallen detritus, are very bad; but from what I saw, I suspect the
real danger is nothing.  With cargo-mules the case is rather different,
for the loads project so far, that the animals, occasionally running
against each other, or against a point of rock, lose their balance, and
are thrown down the precipices.  In crossing the rivers I can well
believe that the difficulty may be very great: at this season there was
little trouble, but in the summer they must be very hazardous.  I can
quite imagine, as Sir F. Head describes, the different expressions of
those who _have_ passed the gulf, and those who _are_ passing.  I never
heard of any man being drowned, but with loaded mules it frequently
happens.  The arriero tells you to show your mule the best line, and
then allow her to cross as she likes: the cargo-mule takes a bad line,
and is often lost.

April 4th.--From the Rio de las Vacas to the Puente del Incas, half a
day's journey.  As there was pasture for the mules, and geology for me,
we bivouacked here for the night.  When one hears of a natural Bridge,
one pictures to one's self some deep and narrow ravine, across which a
bold mass of rock has fallen; or a great arch hollowed out like the
vault of a cavern.  Instead of this, the Incas Bridge consists of a
crust of stratified shingle cemented together by the deposits of the
neighbouring hot springs.  It appears, as if the stream had scooped out
a channel on one side, leaving an overhanging ledge, which was met by
earth and stones falling down from the opposite cliff.  Certainly an
oblique junction, as would happen in such a case, was very distinct on
one side.  The Bridge of the Incas is by no means worthy of the great
monarchs whose name it bears.

5th.--We had a long day's ride across the central ridge, from the Incas
Bridge to the Ojos del Agua, which are situated near the lowest
_casucha_ on the Chilian side.  These casuchas are round little towers,
with steps outside to reach the floor, which is raised some feet above
the ground on account of the snow-drifts.  They are eight in number,
and under the Spanish government were kept during the winter well
stored with food and charcoal, and each courier had a master-key.  Now
they only answer the purpose of caves, or rather dungeons.  Seated on
some little eminence, they are not, however, ill suited to the
surrounding scene of desolation. The zigzag ascent of the Cumbre, or
the partition of the waters, was very steep and tedious; its height,
according to Mr. Pentland, is 12,454 feet.  The road did not pass over
any perpetual snow, although there were patches of it on both hands.
The wind on the summit was exceedingly cold, but it was impossible not
to stop for a few minutes to admire, again and again, the colour of the
heavens, and the brilliant transparency of the atmosphere.  The scenery
was grand: to the westward there was a fine chaos of mountains, divided
by profound ravines.  Some snow generally falls before this period of
the season, and it has even happened that the Cordillera have been
finally closed by this time.  But we were most fortunate.  The sky, by
night and by day, was cloudless, excepting a few round little masses of
vapour, that floated over the highest pinnacles.  I have often seen
these islets in the sky, marking the position of the Cordillera, when
the far-distant mountains have been hidden beneath the horizon.

April 6th.--In the morning we found some thief had stolen one of our
mules, and the bell of the madrina.  We therefore rode only two or
three miles down the valley, and stayed there the ensuing day in hopes
of recovering the mule, which the arriero thought had been hidden in
some ravine. The scenery in this part had assumed a Chilian character:
the lower sides of the mountains, dotted over with the pale evergreen
Quillay tree, and with the great chandelier-like cactus, are certainly
more to be admired than the bare eastern valleys; but I cannot quite
agree with the admiration expressed by some travellers.  The extreme
pleasure, I suspect, is chiefly owing to the prospect of a good fire
and of a good supper, after escaping from the cold regions above: and I
am sure I most heartily participated in these feelings.

8th.--We left the valley of the Aconcagua, by which we had descended,
and reached in the evening a cottage near the Villa del St. Rosa.  The
fertility of the plain was delightful: the autumn being advanced, the
leaves of many of the fruit-trees were falling; and of the
labourers,--some were busy in drying figs and peaches on the roofs of
their cottages, while others were gathering the grapes from the
vineyards. It was a pretty scene; but I missed that pensive stillness
which makes the autumn in England indeed the evening of the year.  On
the 10th we reached Santiago, where I received a very kind and
hospitable reception from Mr. Caldcleugh. My excursion only cost me
twenty-four days, and never did I more deeply enjoy an equal space of
time.  A few days afterwards I returned to Mr. Corfield's house at
Valparaiso.

[1] Scoresby's Arctic Regions, vol. i. p. 122.

[2] I have heard it remarked in Shropshire that the water, when the
Severn is flooded from long-continued rain, is much more turbid than
when it proceeds from the snow melting in the Welsh mountains.
D'Orbigny (tom. i. p. 184), in explaining the cause of the various
colours of the rivers in South America, remarks that those with blue or
clear water have there source in the Cordillera, where the snow melts.

[3] Dr. Gillies in Journ. of Nat. and Geograph. Science, Aug., 1830.
This author gives the heights of the Passes.

[4] This structure in frozen snow was long since observed by Scoresby
in the icebergs near Spitzbergen, and, lately, with more care, by
Colonel Jackson (Journ. of Geograph. Soc., vol. v. p. 12) on the Neva.
Mr. Lyell (Principles, vol. iv. p. 360) has compared the fissures by
which the columnar structure seems to be determined, to the joints that
traverse nearly all rocks, but which are best seen in the
non-stratified masses.  I may observe, that in the case of the frozen
snow, the columnar structure must be owing to a "metamorphic" action,
and not to a process during deposition.

[5] This is merely an illustration of the admirable laws, first laid
down by Mr. Lyell, on the geographical distribution of animals, as
influenced by geological changes.  The whole reasoning, of course, is
founded on the assumption of the immutability of species; otherwise the
difference in the species in the two regions might be considered as
superinduced during a length of time.



CHAPTER XVI

NORTHERN CHILE AND PERU

Coast-road to Coquimbo--Great Loads carried by the
Miners--Coquimbo--Earthquake--Step-formed Terrace--Absence of recent
Deposits--Contemporaneousness of the Tertiary Formations--Excursion up
the Valley--Road to Guasco--Deserts--Valley of Copiapo--Rain and
Earthquakes--Hydrophobia--The Despoblado--Indian Ruins--Probable Change
of Climate--River-bed arched by an Earthquake--Cold Gales of
Wind--Noises from a Hill--Iquique--Salt Alluvium--Nitrate of
Soda--Lima--Unhealthy Country--Ruins of Callao, overthrown by an
Earthquake--Recent Subsidence--Elevated Shells on San Lorenzo, their
decomposition--Plain with embedded Shells and fragments of
Pottery--Antiquity of the Indian Race.


APRIL 27th.--I set out on a journey to Coquimbo, and thence through
Guasco to Copiapo, where Captain Fitz Roy kindly offered to pick me up
in the Beagle. The distance in a straight line along the shore
northward is only 420 miles; but my mode of travelling made it a very
long journey.  I bought four horses and two mules, the latter carrying
the luggage on alternate days.  The six animals together only cost the
value of twenty-five pounds sterling, and at Copiapo I sold them again
for twenty-three. We travelled in the same independent manner as
before, cooking our own meals, and sleeping in the open air.  As we
rode towards the Vino del Mar, I took a farewell view of Valparaiso,
and admired its picturesque appearance.  For geological purposes I made
a detour from the high road to the foot of the Bell of Quillota.  We
passed through an alluvial district rich in gold, to the neighbourhood
of Limache, where we slept.  Washing for gold supports the inhabitants
of numerous hovels, scattered along the sides of each little rivulet;
but, like all those whose gains are uncertain, they are unthrifty in
all their habits, and consequently poor.

28th.--In the afternoon we arrived at a cottage at the foot of the Bell
mountain.  The inhabitants were freeholders, which is not very usual in
Chile.  They supported themselves on the produce of a garden and a
little field, but were very poor.  Capital is here so deficient, that
the people are obliged to sell their green corn while standing in the
field, in order to buy necessaries for the ensuing year.  Wheat in
consequence was dearer in the very district of its production than at
Valparaiso, where the contractors live.  The next day we joined the
main road to Coquimbo.  At night there was a very light shower of rain:
this was the first drop that had fallen since the heavy rain of
September 11th and 12th, which detained me a prisoner at the Baths of
Cauquenes. The interval was seven and a half months; but the rain this
year in Chile was rather later than usual.  The distant Andes were now
covered by a thick mass of snow, and were a glorious sight.

May 2nd.--The road continued to follow the coast, at no great distance
from the sea.  The few trees and bushes which are common in central
Chile decreased rapidly in numbers, and were replaced by a tall plant,
something like a yucca in appearance.  The surface of the country, on a
small scale, was singularly broken and irregular; abrupt little peaks
of rock rising out of small plains or basins.  The indented coast and
the bottom of the neighbouring sea, studded with breakers, would, if
converted into dry land, present similar forms; and such a conversion
without doubt has taken place in the part over which we rode.

3rd.--Quilimari to Conchalee.  The country became more and more barren.
In the valleys there was scarcely sufficient water for any irrigation;
and the intermediate land was quite bare, not supporting even goats. In
the spring, after the winter showers, a thin pasture rapidly springs
up, and cattle are then driven down from the Cordillera to graze for a
short time.  It is curious to observe how the seeds of the grass and
other plants seem to accommodate themselves, as if by an acquired
habit, to the quantity of rain which falls upon different parts of this
coast.  One shower far northward at Copiapo produces as great an effect
on the vegetation, as two at Guasco, and three or four in this
district.  At Valparaiso a winter so dry as greatly to injure the
pasture, would at Guasco produce the most unusual abundance. Proceeding
northward, the quantity of rain does not appear to decrease in strict
proportion to the latitude. At Conchalee, which is only 67 miles north
of Valparaiso, rain is not expected till the end of May; whereas at
Valparaiso some generally falls early in April: the annual quantity is
likewise small in proportion to the lateness of the season at which it
commences.

4th.--Finding the coast-road devoid of interest of any kind, we turned
inland towards the mining district and valley of Illapel.  This valley,
like every other in Chile, is level, broad, and very fertile: it is
bordered on each side, either by cliffs of stratified shingle, or by
bare rocky mountains.  Above the straight line of the uppermost
irrigating ditch, all is brown as on a high road; while all below is of
as bright a green as verdigris, from the beds of alfalfa, a kind of
clover.  We proceeded to Los Hornos, another mining district, where the
principal hill was drilled with holes, like a great ants'-nest.  The
Chilian miners are a peculiar race of men in their habits.  Living for
weeks together in the most desolate spots, when they descend to the
villages on feast-days, there is no excess of extravagance into which
they do not run.  They sometimes gain a considerable sum, and then,
like sailors with prize-money, they try how soon they can contrive to
squander it.  They drink excessively, buy quantities of clothes, and in
a few days return penniless to their miserable abodes, there to work
harder than beasts of burden.  This thoughtlessness, as with sailors,
is evidently the result of a similar manner of life.  Their daily food
is found them, and they acquire no habits of carefulness: moreover,
temptation and the means of yielding to it are placed in their power at
the same time.  On the other hand, in Cornwall, and some other parts of
England, where the system of selling part of the vein is followed, the
miners, from being obliged to act and think for themselves, are a
singularly intelligent and well-conducted set of men.

The dress of the Chilian miner is peculiar and rather picturesque He
wears a very long shirt of some dark-coloured baize, with a leathern
apron; the whole being fastened round his waist by a bright-coloured
sash.  His trousers are very broad, and his small cap of scarlet cloth
is made to fit the head closely.  We met a party of these miners in
full costume, carrying the body of one of their companions to be
buried.  They marched at a very quick trot, four men supporting the
corpse.  One set having run as hard as they could for about two hundred
yards, were relieved by four others, who had previously dashed on ahead
on horseback. Thus they proceeded, encouraging each other by wild
cries: altogether the scene formed a most strange funeral.

We continued travelling northward, in a zigzag line; sometimes stopping
a day to geologize.  The country was so thinly inhabited, and the track
so obscure, that we often had difficulty in finding our way.  On the
12th I stayed at some mines.  The ore in this case was not considered
particularly good, but from being abundant it was supposed the mine
would sell for about thirty or forty thousand dollars (that is, 6000 or
8000 pounds sterling); yet it had been bought by one of the English
Associations for an ounce of gold (3l. 8s.).  The ore is yellow
pyrites, which, as I have already remarked, before the arrival of the
English, was not supposed to contain a particle of copper.  On a scale
of profits nearly as great as in the above instance, piles of cinders,
abounding with minute globules of metallic copper, were purchased; yet
with these advantages, the mining associations, as is well known,
contrived to lose immense sums of money.  The folly of the greater
number of the commissioners and shareholders amounted to
infatuation;--a thousand pounds per annum given in some cases to
entertain the Chilian authorities; libraries of well-bound geological
books; miners brought out for particular metals, as tin, which are not
found in Chile; contracts to supply the miners with milk, in parts
where there are no cows; machinery, where it could not possibly be
used; and a hundred similar arrangements, bore witness to our
absurdity, and to this day afford amusement to the natives.  Yet there
can be no doubt, that the same capital well employed in these mines
would have yielded an immense return, a confidential man of business, a
practical miner and assayer, would have been all that was required.

Captain Head has described the wonderful load which the "Apires," truly
beasts of burden, carry up from the deepest mines.  I confess I thought
the account exaggerated: so that I was glad to take an opportunity of
weighing one of the loads, which I picked out by hazard.  It required
considerable exertion on my part, when standing directly over it, to
lift it from the ground.  The load was considered under weight when
found to be 197 pounds.  The apire had carried this up eighty
perpendicular yards,--part of the way by a steep passage, but the
greater part up notched poles, placed in a zigzag line up the shaft.
According to the general regulation, the apire is not allowed to halt
for breath, except the mine is six hundred feet deep.  The average load
is considered as rather more than 200 pounds, and I have been assured
that one of 300 pounds (twenty-two stone and a half) by way of a trial
has been brought up from the deepest mine! At this time the apires were
bringing up the usual load twelve times in the day; that is 2400 pounds
from eighty yards deep; and they were employed in the intervals in
breaking and picking ore.

These men, excepting from accidents, are healthy, and appear cheerful.
Their bodies are not very muscular.  They rarely eat meat once a week,
and never oftener, and then only the hard dry charqui.  Although with a
knowledge that the labour was voluntary, it was nevertheless quite
revolting to see the state in which they reached the mouth of the mine;
their bodies bent forward, leaning with their arms on the steps, their
legs bowed, their muscles quivering, the perspiration streaming from
their faces over their breasts, their nostrils distended, the corners
of their mouth forcibly drawn back, and the expulsion of their breath
most laborious. Each time they draw their breath, they utter an
articulate cry of "ay-ay," which ends in a sound rising from deep in
the chest, but shrill like the note of a fife.  After staggering to the
pile of ore, they emptied the "carpacho;" in two or three seconds
recovering their breath, they wiped the sweat from their brows, and
apparently quite fresh descended the mine again at a quick pace.  This
appears to me a wonderful instance of the amount of labour which habit,
for it can be nothing else, will enable a man to endure.

In the evening, talking with the _mayor-domo_ of these mines about the
number of foreigners now scattered over the whole country, he told me
that, though quite a young man, he remembers when he was a boy at
school at Coquimbo, a holiday being given to see the captain of an
English ship, who was brought to the city to speak to the governor.  He
believes that nothing would have induced any boy in the school, himself
included, to have gone close to the Englishman; so deeply had they been
impressed with an idea of the heresy, contamination, and evil to be
derived from contact with such a person.  To this day they relate the
atrocious actions of the bucaniers; and especially of one man, who took
away the figure of the Virgin Mary, and returned the year after for
that of St. Joseph, saying it was a pity the lady should not have a
husband.  I heard also of an old lady who, at a dinner at Coquimbo,
remarked how wonderfully strange it was that she should have lived to
dine in the same room with an Englishman; for she remembered as a girl,
that twice, at the mere cry of "Los Ingleses," every soul, carrying
what valuables they could, had taken to the mountains.

14th.--We reached Coquimbo, where we stayed a few days.  The town is
remarkable for nothing but its extreme quietness.  It is said to
contain from 6000 to 8000 inhabitants. On the morning of the 17th it
rained lightly, the first time this year, for about five hours.  The
farmers, who plant corn near the sea-coast where the atmosphere is most
humid, taking advantage of this shower, would break up the ground;
after a second they would put the seed in; and if a third shower should
fall, they would reap a good harvest in the spring.  It was interesting
to watch the effect of this trifling amount of moisture.  Twelve hours
afterwards the ground appeared as dry as ever; yet after an interval of
ten days, all the hills were faintly tinged with green patches; the
grass being sparingly scattered in hair-like fibres a full inch in
length.  Before this shower every part of the surface was bare as on a
high road.

In the evening, Captain Fitz Roy and myself were dining with Mr.
Edwards, an English resident well known for his hospitality by all who
have visited Coquimbo, when a sharp earthquake happened.  I heard the
forecoming rumble, but from the screams of the ladies, the running of
the servants, and the rush of several of the gentlemen to the doorway,
I could not distinguish the motion.  Some of the women afterwards were
crying with terror, and one gentleman said he should not be able to
sleep all night, or if he did, it would only be to dream of falling
houses.  The father of this person had lately lost all his property at
Talcahuano, and he himself had only just escaped a falling roof at
Valparaiso, in 1822.  He mentioned a curious coincidence which then
happened: he was playing at cards, when a German, one of the party, got
up, and said he would never sit in a room in these countries with the
door shut, as owing to his having done so, he had nearly lost his life
at Copiapo.  Accordingly he opened the door; and no sooner had he done
this, than he cried out, "Here it comes again!" and the famous shock
commenced.  The whole party escaped.  The danger in an earthquake is
not from the time lost in opening the door, but from the chance of its
becoming jammed by the movement of the walls.

It is impossible to be much surprised at the fear which natives and old
residents, though some of them known to be men of great command of
mind, so generally experience during earthquakes.  I think, however,
this excess of panic may be partly attributed to a want of habit in
governing their fear, as it is not a feeling they are ashamed of.
Indeed, the natives do not like to see a person indifferent.  I heard
of two Englishmen who, sleeping in the open air during a smart shock,
knowing that there was no danger, did not rise.  The natives cried out
indignantly, "Look at those heretics, they do not even get out of their
beds!"


I spent some days in examining the step-formed terraces of shingle,
first noticed by Captain B. Hall, and believed by Mr. Lyell to have
been formed by the sea, during the gradual rising of the land.  This
certainly is the true explanation, for I found numerous shells of
existing species on these terraces.  Five narrow, gently sloping,
fringe-like terraces rise one behind the other, and where best
developed are formed of shingle: they front the bay, and sweep up both
sides of the valley.  At Guasco, north of Coquimbo, the phenomenon is
displayed on a much grander scale, so as to strike with surprise even
some of the inhabitants.  The terraces are there much broader, and may
be called plains, in some parts there are six of them, but generally
only five; they run up the valley for thirty-seven miles from the
coast. These step-formed terraces or fringes closely resemble those in
the valley of S. Cruz, and, except in being on a smaller scale, those
great ones along the whole coast-line of Patagonia. They have
undoubtedly been formed by the denuding power of the sea, during long
periods of rest in the gradual elevation of the continent.

Shells of many existing species not only lie on the surface of the
terraces at Coquimbo (to a height of 250 feet), but are embedded in a
friable calcareous rock, which in some places is as much as between
twenty and thirty feet in thickness, but is of little extent.  These
modern beds rest on an ancient tertiary formation containing shells,
apparently all extinct.  Although I examined so many hundred miles of
coast on the Pacific, as well as Atlantic side of the continent, I
found no regular strata containing sea-shells of recent species,
excepting at this place, and at a few points northward on the road to
Guasco.  This fact appears to me highly remarkable; for the explanation
generally given by geologists, of the absence in any district of
stratified fossiliferous deposits of a given period, namely, that the
surface then existed as dry land, is not here applicable; for we know
from the shells strewed on the surface and embedded in loose sand or
mould that the land for thousands of miles along both coasts has lately
been submerged.  The explanation, no doubt, must be sought in the fact,
that the whole southern part of the continent has been for a long time
slowly rising; and therefore that all matter deposited along shore in
shallow water, must have been soon brought up and slowly exposed to the
wearing action of the sea-beach; and it is only in comparatively
shallow water that the greater number of marine organic beings can
flourish, and in such water it is obviously impossible that strata of
any great thickness can accumulate.  To show the vast power of the
wearing action of sea-beaches, we need only appeal to the great cliffs
along the present coast of Patagonia, and to the escarpments or ancient
sea-cliffs at different levels, one above another, on that same line of
coast.

The old underlying tertiary formation at Coquimbo, appears to be of
about the same age with several deposits on the coast of Chile (of
which that of Navedad is the principal one), and with the great
formation of Patagonia. Both at Navedad and in Patagonia there is
evidence, that since the shells (a list of which has been seen by
Professor E. Forbes) there entombed were living, there has been a
subsidence of several hundred feet, as well as an ensuing elevation. It
may naturally be asked, how it comes that, although no extensive
fossiliferous deposits of the recent period, nor of any period
intermediate between it and the ancient tertiary epoch, have been
preserved on either side of the continent, yet that at this ancient
tertiary epoch, sedimentary matter containing fossil remains, should
have been deposited and preserved at different points in north and
south lines, over a space of 1100 miles on the shores of the Pacific,
and of at least 1350 miles on the shores of the Atlantic, and in an
east and west line of 700 miles across the widest part of the
continent?  I believe the explanation is not difficult, and that it is
perhaps applicable to nearly analogous facts observed in other quarters
of the world. Considering the enormous power of denudation which the
sea possesses, as shown by numberless facts, it is not probable that a
sedimentary deposit, when being upraised, could pass through the ordeal
of the beach, so as to be preserved in sufficient masses to last to a
distant period, without it were originally of wide extent and of
considerable thickness: now it is impossible on a moderately shallow
bottom, which alone is favourable to most living creatures, that a
thick and widely extended covering of sediment could be spread out,
without the bottom sank down to receive the successive layers.  This
seems to have actually taken place at about the same period in southern
Patagonia and Chile, though these places are a thousand miles apart.
Hence, if prolonged movements of approximately contemporaneous
subsidence are generally widely extensive, as I am strongly inclined to
believe from my examination of the Coral Reefs of the great oceans--or
if, confining our view to South America, the subsiding movements have
been co-extensive with those of elevation, by which, within the same
period of existing shells, the shores of Peru, Chile, Tierra del Fuego,
Patagonia, and La Plata have been upraised--then we can see that at the
same time, at far distant points, circumstances would have been
favourable to the formation of fossiliferous deposits of wide extent
and of considerable thickness; and such deposits, consequently, would
have a good chance of resisting the wear and tear of successive
beach-lines, and of lasting to a future epoch.


May 21st.--I set out in company with Don Jose Edwards to the
silver-mine of Arqueros, and thence up the valley of Coquimbo.  Passing
through a mountainous country, we reached by nightfall the mines
belonging to Mr. Edwards. I enjoyed my night's rest here from a reason
which will not be fully appreciated in England, namely, the absence of
fleas!  The rooms in Coquimbo swarm with them; but they will not live
here at the height of only three or four thousand feet: it can scarcely
be the trifling diminution of temperature, but some other cause which
destroys these troublesome insects at this place.  The mines are now in
a bad state, though they formerly yielded about 2000 pounds in weight
of silver a year.  It has been said that "a person with a copper-mine
will gain; with silver he may gain; but with gold he is sure to lose."
This is not true: all the large Chilian fortunes have been made by
mines of the more precious metals.  A short time since an English
physician returned to England from Copiapo, taking with him the profits
of one share of a silver-mine, which amounted to about 24,000 pounds
sterling.  No doubt a copper-mine with care is a sure game, whereas the
other is gambling, or rather taking a ticket in a lottery.  The owners
lose great quantities of rich ores; for no precautions can prevent
robberies. I heard of a gentleman laying a bet with another, that one
of his men should rob him before his face.  The ore when brought out of
the mine is broken into pieces, and the useless stone thrown on one
side.  A couple of the miners who were thus employed, pitched, as if by
accident, two fragments away at the same moment, and then cried out for
a joke "Let us see which rolls furthest." The owner, who was standing
by, bet a cigar with his friend on the race.  The miner by this means
watched the very point amongst the rubbish where the stone lay.  In the
evening he picked it up and carried it to his master, showing him a
rich mass of silver-ore, and saying, "This was the stone on which you
won a cigar by its rolling so far."

May 23rd.--We descended into the fertile valley of Coquimbo, and
followed it till we reached an Hacienda belonging to a relation of Don
Jose, where we stayed the next day. I then rode one day's journey
further, to see what were declared to be some petrified shells and
beans, which latter turned out to be small quartz pebbles.  We passed
through several small villages; and the valley was beautifully
cultivated, and the whole scenery very grand.  We were here near the
main Cordillera, and the surrounding hills were lofty.  In all parts of
northern Chile, fruit trees produce much more abundantly at a
considerable height near the Andes than in the lower country.  The figs
and grapes of this district are famous for their excellence, and are
cultivated to a great extent.  This valley is, perhaps, the most
productive one north of Quillota.  I believe it contains, including
Coquimbo, 25,000 inhabitants.  The next day I returned to the Hacienda,
and thence, together with Don Jose, to Coquimbo.

June 2nd.--We set out for the valley of Guasco, following the
coast-road, which was considered rather less desert than the other. Our
first day's ride was to a solitary house, called Yerba Buena, where
there was pasture for our horses.  The shower mentioned as having
fallen, a fortnight ago, only reached about half-way to Guasco; we had,
therefore, in the first part of our journey a most faint tinge of
green, which soon faded quite away.  Even where brightest, it was
scarcely sufficient to remind one of the fresh turf and budding flowers
of the spring of other countries.  While travelling through these
deserts one feels like a prisoner shut up in a gloomy court, who longs
to see something green and to smell a moist atmosphere.

June 3rd.--Yerba Buena to Carizal.  During the first part of the day we
crossed a mountainous rocky desert, and afterwards a long deep sandy
plain, strewed with broken sea-shells. There was very little water, and
that little saline: the whole country, from the coast to the
Cordillera, is an uninhabited desert.  I saw traces only of one living
animal in abundance, namely, the shells of a Bulimus, which were
collected together in extraordinary numbers on the driest spots.  In
the spring one humble little plant sends out a few leaves, and on these
the snails feed.  As they are seen only very early in the morning, when
the ground is slightly damp with dew, the Guascos believe that they are
bred from it.  I have observed in other places that extremely dry and
sterile districts, where the soil is calcareous, are extraordinarily
favourable to land-shells.  At Carizal there were a few cottages, some
brackish water, and a trace of cultivation: but it was with difficulty
that we purchased a little corn and straw for our horses.

4th.--Carizal to Sauce.  We continued to ride over desert plains,
tenanted by large herds of guanaco.  We crossed also the valley of
Chaneral; which, although the most fertile one between Guasco and
Coquimbo, is very narrow, and produces so little pasture, that we could
not purchase any for our horses.  At Sauce we found a very civil old
gentleman, superintendent of a copper-smelting furnace.  As an especial
favour, he allowed me to purchase at a high price an armful of dirty
straw, which was all the poor horses had for supper after their long
day's journey.  Few smelting-furnaces are now at work in any part of
Chile; it is found more profitable, on account of the extreme scarcity
of firewood, and from the Chilian method of reduction being so
unskilful, to ship the ore for Swansea.  The next day we crossed some
mountains to Freyrina, in the valley of Guasco.  During each day's ride
further northward, the vegetation became more and more scanty; even the
great chandelier-like cactus was here replaced by a different and much
smaller species.  During the winter months, both in northern Chile and
in Peru, a uniform bank of clouds hangs, at no great height, over the
Pacific. From the mountains we had a very striking view of this white
and brilliant aerial-field, which sent arms up the valleys, leaving
islands and promontories in the same manner, as the sea does in the
Chonos archipelago and in Tierra del Fuego.

We stayed two days at Freyrina.  In the valley of Guasco there are four
small towns.  At the mouth there is the port, a spot entirely desert,
and without any water in the immediate neighbourhood.  Five leagues
higher up stands Freyrina, a long straggling village, with decent
whitewashed houses. Again, ten leagues further up Ballenar is situated,
and above this Guasco Alto, a horticultural village, famous for its
dried fruit.  On a clear day the view up the valley is very fine; the
straight opening terminates in the far-distant snowy Cordillera; on
each side an infinity of crossing-lines are blended together in a
beautiful haze.  The foreground is singular from the number of parallel
and step-formed terraces; and the included strip of green valley, with
its willow-bushes, is contrasted on both hands with the naked hills.
That the surrounding country was most barren will be readily believed,
when it is known that a shower of rain had not fallen during the last
thirteen months.  The inhabitants heard with the greatest envy of the
rain at Coquimbo; from the appearance of the sky they had hopes of
equally good fortune, which, a fortnight afterwards, were realized.  I
was at Copiapo at the time; and there the people, with equal envy,
talked of the abundant rain at Guasco.  After two or three very dry
years, perhaps with not more than one shower during the whole time, a
rainy year generally follows; and this does more harm than even the
drought.  The rivers swell, and cover with gravel and sand the narrow
strips of ground, which alone are fit for cultivation.  The floods also
injure the irrigating ditches.  Great devastation had thus been caused
three years ago.

June 8th.--We rode on to Ballenar, which takes its name from Ballenagh
in Ireland, the birthplace of the family of O'Higgins, who, under the
Spanish government, were presidents and generals in Chile. As the rocky
mountains on each hand were concealed by clouds, the terrace-like
plains gave to the valley an appearance like that of Santa Cruz in
Patagonia.  After spending one day at Ballenar I set out, on the 10th,
for the upper part of the valley of Copiapo.  We rode all day over an
uninteresting country.  I am tired of repeating the epithets barren and
sterile.  These words, however, as commonly used, are comparative; I
have always applied them to the plains of Patagonia, which can boast of
spiny bushes and some tufts of grass; and this is absolute fertility,
as compared with northern Chile.  Here again, there are not many spaces
of two hundred yards square, where some little bush, cactus or lichen,
may not be discovered by careful examination; and in the soil seeds lie
dormant ready to spring up during the first rainy winter.  In Peru real
deserts occur over wide tracts of country. In the evening we arrived at
a valley, in which the bed of the streamlet was damp: following it up,
we came to tolerably good water. During the night, the stream, from not
being evaporated and absorbed so quickly, flows a league lower down
than during the day.  Sticks were plentiful for firewood, so that it
was a good place to bivouac for us; but for the poor animals there was
not a mouthful to eat.

June 11th.--We rode without stopping for twelve hours till we reached
an old smelting-furnace, where there was water and firewood; but our
horses again had nothing to eat, being shut up in an old courtyard. The
line of road was hilly, and the distant views interesting, from the
varied colours of the bare mountains.  It was almost a pity to see the
sun shining constantly over so useless a country; such splendid weather
ought to have brightened fields and pretty gardens.  The next day we
reached the valley of Copiapo. I was heartily glad of it; for the whole
journey was a continued source of anxiety; it was most disagreeable to
hear, whilst eating our own suppers, our horses gnawing the posts to
which they were tied, and to have no means of relieving their hunger.
To all appearance, however, the animals were quite fresh; and no one
could have told that they had eaten nothing for the last fifty-five
hours.

I had a letter of introduction to Mr. Bingley, who received me very
kindly at the Hacienda of Potrero Seco.  This estate is between twenty
and thirty miles long, but very narrow, being generally only two fields
wide, one on each side the river.  In some parts the estate is of no
width, that is to say, the land cannot be irrigated, and therefore is
valueless, like the surrounding rocky desert.  The small quantity of
cultivated land in the whole line of valley, does not so much depend on
inequalities of level, and consequent unfitness for irrigation, as on
the small supply of water.  The river this year was remarkably full:
here, high up the valley, it reached to the horse's belly, and was
about fifteen yards wide, and rapid; lower down it becomes smaller and
smaller, and is generally quite lost, as happened during one period of
thirty years, so that not a drop entered the sea.  The inhabitants
watch a storm over the Cordillera with great interest; as one good fall
of snow provides them with water for the ensuing year.  This is of
infinitely more consequence than rain in the lower country.  Rain, as
often as it falls, which is about once in every two or three years, is
a great advantage, because the cattle and mules can for some time
afterwards find a little pasture in the mountains.  But without snow on
the Andes, desolation extends throughout the valley.  It is on record
that three times nearly all the inhabitants have been obliged to
emigrate to the south.  This year there was plenty of water, and every
man irrigated his ground as much as he chose; but it has frequently
been necessary to post soldiers at the sluices, to see that each estate
took only its proper allowance during so many hours in the week.  The
valley is said to contain 12,000 souls, but its produce is sufficient
only for three months in the year; the rest of the supply being drawn
from Valparaiso and the south.  Before the discovery of the famous
silver-mines of Chanuncillo, Copiapo was in a rapid state of decay; but
now it is in a very thriving condition; and the town, which was
completely overthrown by an earthquake, has been rebuilt.

The valley of Copiapo, forming a mere ribbon of green in a desert, runs
in a very southerly direction; so that it is of considerable length to
its source in the Cordillera.  The valleys of Guasco and Copiapo may
both be considered as long narrow islands, separated from the rest of
Chile by deserts of rock instead of by salt water.  Northward of these,
there is one other very miserable valley, called Paposo, which contains
about two hundred souls; and then there extends the real desert of
Atacama--a barrier far worse than the most turbulent ocean.  After
staying a few days at Potrero Seco, I proceeded up the valley to the
house of Don Benito Cruz, to whom I had a letter of introduction.  I
found him most hospitable; indeed it is impossible to bear too strong
testimony to the kindness with which travellers are received in almost
every part of South America.  The next day I hired some mules to take
me by the ravine of Jolquera into the central Cordillera.  On the
second night the weather seemed to foretell a storm of snow or rain,
and whilst lying in our beds we felt a trifling shock of an earthquake.

The connection between earthquakes and the weather has been often
disputed: it appears to me to be a point of great interest, which is
little understood.  Humboldt has remarked in one part of the Personal
Narrative, [1] that it would be difficult for any person who had long
resided in New Andalusia, or in Lower Peru, to deny that there exists
some connection between these phenomena: in another part, however he
seems to think the connection fanciful.  At Guayaquil it is said that a
heavy shower in the dry season is invariably followed by an earthquake.
In Northern Chile, from the extreme infrequency of rain, or even of
weather foreboding rain, the probability of accidental coincidences
becomes very small; yet the inhabitants are here most firmly convinced
of some connection between the state of the atmosphere and of the
trembling of the ground: I was much struck by this when mentioning to
some people at Copiapo that there had been a sharp shock at Coquimbo:
they immediately cried out, "How fortunate! there will be plenty of
pasture there this year." To their minds an earthquake foretold rain as
surely as rain foretold abundant pasture.  Certainly it did so happen
that on the very day of the earthquake, that shower of rain fell, which
I have described as in ten days' time producing a thin sprinkling of
grass.  At other times rain has followed earthquakes at a period of the
year when it is a far greater prodigy than the earthquake itself: this
happened after the shock of November, 1822, and again in 1829, at
Valparaiso; also after that of September, 1833, at Tacna. A person must
be somewhat habituated to the climate of these countries to perceive
the extreme improbability of rain falling at such seasons, except as a
consequence of some law quite unconnected with the ordinary course of
the weather. In the cases of great volcanic eruptions, as that of
Coseguina, where torrents of rain fell at a time of the year most
unusual for it, and "almost unprecedented in Central America," it is
not difficult to understand that the volumes of vapour and clouds of
ashes might have disturbed the atmospheric equilibrium.  Humboldt
extends this view to the case of earthquakes unaccompanied by
eruptions; but I can hardly conceive it possible, that the small
quantity of aeriform fluids which then escape from the fissured ground,
can produce such remarkable effects.  There appears much probability in
the view first proposed by Mr. P. Scrope, that when the barometer is
low, and when rain might naturally be expected to fall, the diminished
pressure of the atmosphere over a wide extent of country, might well
determine the precise day on which the earth, already stretched to the
utmost by the subterranean forces, should yield, crack, and
consequently tremble.  It is, however, doubtful how far this idea will
explain the circumstances of torrents of rain falling in the dry season
during several days, after an earthquake unaccompanied by an eruption;
such cases seem to bespeak some more intimate connection between the
atmospheric and subterranean regions.

Finding little of interest in this part of the ravine, we retraced our
steps to the house of Don Benito, where I stayed two days collecting
fossil shells and wood.  Great prostrate silicified trunks of trees,
embedded in a conglomerate, were extraordinarily numerous.  I measured
one, which was fifteen feet in circumference: how surprising it is that
every atom of the woody matter in this great cylinder should have been
removed and replaced by silex so perfectly, that each vessel and pore
is preserved!  These trees flourished at about the period of our lower
chalk; they all belonged to the fir-tribe.  It was amusing to hear the
inhabitants discussing the nature of the fossil shells which I
collected, almost in the same terms as were used a century ago in
Europe,--namely, whether or not they had been thus "born by nature." My
geological examination of the country generally created a good deal of
surprise amongst the Chilenos: it was long before they could be
convinced that I was not hunting for mines.  This was sometimes
troublesome: I found the most ready way of explaining my employment,
was to ask them how it was that they themselves were not curious
concerning earthquakes and volcanos?--why some springs were hot and
others cold?--why there were mountains in Chile, and not a hill in La
Plata?  These bare questions at once satisfied and silenced the greater
number; some, however (like a few in England who are a century
behindhand), thought that all such inquiries were useless and impious;
and that it was quite sufficient that God had thus made the mountains.

An order had recently been issued that all stray dogs should be killed,
and we saw many lying dead on the road.  A great number had lately gone
mad, and several men had been bitten and had died in consequence.  On
several occasions hydrophobia has prevailed in this valley.  It is
remarkable thus to find so strange and dreadful a disease, appearing
time after time in the same isolated spot.  It has been remarked that
certain villages in England are in like manner much more subject to
this visitation than others.  Dr. Unanue states that hydrophobia was
first known in South America in 1803: this statement is corroborated by
Azara and Ulloa having never heard of it in their time.  Dr. Unanue
says that it broke out in Central America, and slowly travelled
southward.  It reached Arequipa in 1807; and it is said that some men
there, who had not been bitten, were affected, as were some negroes,
who had eaten a bullock which had died of hydrophobia.  At Ica
forty-two people thus miserably perished.  The disease came on between
twelve and ninety days after the bite; and in those cases where it did
come on, death ensued invariably within five days.  After 1808, a long
interval ensued without any cases.  On inquiry, I did not hear of
hydrophobia in Van Diemen's Land, or in Australia; and Burchell says,
that during the five years he was at the Cape of Good Hope, he never
heard of an instance of it.  Webster asserts that at the Azores
hydrophobia has never occurred; and the same assertion has been made
with respect to Mauritius and St. Helena. [2] In so strange a disease
some information might possibly be gained by considering the
circumstances under which it originates in distant climates; for it is
improbable that a dog already bitten, should have been brought to these
distant countries.

At night, a stranger arrived at the house of Don Benito, and asked
permission to sleep there.  He said he had been wandering about the
mountains for seventeen days, having lost his way.  He started from
Guasco, and being accustomed to travelling in the Cordillera, did not
expect any difficulty in following the track to Copiapo; but he soon
became involved in a labyrinth of mountains, whence he could not
escape.  Some of his mules had fallen over precipices, and he had been
in great distress.  His chief difficulty arose from not knowing where
to find water in the lower country, so that he was obliged to keep
bordering the central ranges.

We returned down the valley, and on the 22nd reached the town of
Copiapo.  The lower part of the valley is broad, forming a fine plain
like that of Quillota.  The town covers a considerable space of ground,
each house possessing a garden: but it is an uncomfortable place, and
the dwellings are poorly furnished.  Every one seems bent on the one
object of making money, and then migrating as quickly as possible. All
the inhabitants are more or less directly concerned with mines; and
mines and ores are the sole subjects of conversation. Necessaries of
all sorts are extremely dear; as the distance from the town to the port
is eighteen leagues, and the land carriage very expensive.  A fowl
costs five or six shillings; meat is nearly as dear as in England;
firewood, or rather sticks, are brought on donkeys from a distance of
two and three days' journey within the Cordillera; and pasturage for
animals is a shilling a day: all this for South America is wonderfully
exorbitant.


June 26th.--I hired a guide and eight mules to take me into the
Cordillera by a different line from my last excursion. As the country
was utterly desert, we took a cargo and a half of barley mixed with
chopped straw.  About two leagues above the town a broad valley called
the "Despoblado," or uninhabited, branches off from that one by which
we had arrived.  Although a valley of the grandest dimensions, and
leading to a pass across the Cordillera, yet it is completely dry,
excepting perhaps for a few days during some very rainy winter.  The
sides of the crumbling mountains were furrowed by scarcely any ravines;
and the bottom of the main valley, filled with shingle, was smooth and
nearly level.  No considerable torrent could ever have flowed down this
bed of shingle; for if it had, a great cliff-bounded channel, as in all
the southern valleys, would assuredly have been formed.  I feel little
doubt that this valley, as well as those mentioned by travellers in
Peru, were left in the state we now see them by the waves of the sea,
as the land slowly rose.  I observed in one place, where the Despoblado
was joined by a ravine (which in almost any other chain would have been
called a grand valley), that its bed, though composed merely of sand
and gravel, was higher than that of its tributary. A mere rivulet of
water, in the course of an hour, would have cut a channel for itself;
but it was evident that ages had passed away, and no such rivulet had
drained this great tributary.  It was curious to behold the machinery,
if such a term may be used, for the drainage, all, with the last
trifling exception, perfect, yet without any signs of action.  Every
one must have remarked how mud-banks, left by the retiring tide,
imitate in miniature a country with hill and dale; and here we have the
original model in rock, formed as the continent rose during the secular
retirement of the ocean, instead of during the ebbing and flowing of
the tides.  If a shower of rain falls on the mud-bank, when left dry,
it deepens the already-formed shallow lines of excavation; and so it is
with the rain of successive centuries on the bank of rock and soil,
which we call a continent.

We rode on after it was dark, till we reached a side ravine with a
small well, called "Agua amarga." The water deserved its name, for
besides being saline it was most offensively putrid and bitter; so that
we could not force ourselves to drink either tea or mate.  I suppose
the distance from the river of Copiapo to this spot was at least
twenty-five or thirty English miles; in the whole space there was not a
single drop of water, the country deserving the name of desert in the
strictest sense.  Yet about half way we passed some old Indian ruins
near Punta Gorda: I noticed also in front of some of the valleys, which
branch off from the Despoblado, two piles of stones placed a little way
apart, and directed so as to point up the mouths of these small
valleys.  My companions knew nothing about them, and only answered my
queries by their imperturbable "quien sabe?"

I observed Indian ruins in several parts of the Cordillera: the most
perfect which I saw, were the Ruinas de Tambillos, in the Uspallata
Pass.  Small square rooms were there huddled together in separate
groups: some of the doorways were yet standing; they were formed by a
cross slab of stone only about three feet high.  Ulloa has remarked on
the lowness of the doors in the ancient Peruvian dwellings.  These
houses, when perfect, must have been capable of containing a
considerable number of persons.  Tradition says, that they were used as
halting-places for the Incas, when they crossed the mountains.  Traces
of Indian habitations have been discovered in many other parts, where
it does not appear probable that they were used as mere resting-places,
but yet where the land is as utterly unfit for any kind of cultivation,
as it is near the Tambillos or at the Incas Bridge, or in the Portillo
Pass, at all which places I saw ruins.  In the ravine of Jajuel, near
Aconcagua, where there is no pass, I heard of remains of houses
situated at a great height, where it is extremely cold and sterile.  At
first I imagined that these buildings had been places of refuge, built
by the Indians on the first arrival of the Spaniards; but I have since
been inclined to speculate on the probability of a small change of
climate.

In this northern part of Chile, within the Cordillera, old Indian
houses are said to be especially numerous: by digging amongst the
ruins, bits of woollen articles, instruments of precious metals, and
heads of Indian corn, are not unfrequently discovered: an arrow-head
made of agate, and of precisely the same form with those now used in
Tierra del Fuego, was given me.  I am aware that the Peruvian Indians
now frequently inhabit most lofty and bleak situations; but at Copiapo
I was assured by men who had spent their lives in travelling through
the Andes, that there were very many (muchisimas)  buildings at heights
so great as almost to border upon the perpetual snow, and in parts
where there exist no passes, and where the land produces absolutely
nothing, and what is still more extraordinary, where there is no water.
Nevertheless it is the opinion of the people of the country (although
they are much puzzled by the circumstance), that, from the appearance
of the houses, the Indians must have used them as places of residence.
In this valley, at Punta Gorda, the remains consisted of seven or eight
square little rooms, which were of a similar form with those at
Tambillos, but built chiefly of mud, which the present inhabitants
cannot, either here or, according to Ulloa, in Peru, imitate in
durability.  They were situated in the most conspicuous and defenceless
position, at the bottom of the flat broad valley. There was no water
nearer than three or four leagues, and that only in very small
quantity, and bad: the soil was absolutely sterile; I looked in vain
even for a lichen adhering to the rocks.  At the present day, with the
advantage of beasts of burden, a mine, unless it were very rich, could
scarcely be worked here with profit.  Yet the Indians formerly chose it
as a place of residence!  If at the present time two or three showers
of rain were to fall annually, instead of one, as now is the case
during as many years, a small rill of water would probably be formed in
this great valley; and then, by irrigation (which was formerly so well
understood by the Indians), the soil would easily be rendered
sufficiently productive to support a few families.

I have convincing proofs that this part of the continent of South
America has been elevated near the coast at least from 400 to 500, and
in some parts from 1000 to 1300 feet, since the epoch of existing
shells; and further inland the rise possibly may have been greater.  As
the peculiarly arid character of the climate is evidently a consequence
of the height of the Cordillera, we may feel almost sure that before
the later elevations, the atmosphere could not have been so completely
drained of its moisture as it now is; and as the rise has been gradual,
so would have been the change in climate.  On this notion of a change
of climate since the buildings were inhabited, the ruins must be of
extreme antiquity, but I do not think their preservation under the
Chilian climate any great difficulty.  We must also admit on this
notion (and this perhaps is a greater difficulty) that man has
inhabited South America for an immensely long period, inasmuch as any
change of climate effected by the elevation of the land must have been
extremely gradual.  At Valparaiso, within the last 220 years, the rise
has been somewhat less than 19 feet: at Lima a sea-beach has certainly
been upheaved from 80 to 90 feet, within the Indo-human period: but
such small elevations could have had little power in deflecting the
moisture-bringing atmospheric currents.  Dr. Lund, however, found human
skeletons in the caves of Brazil, the appearance of which induced him
to believe that the Indian race has existed during a vast lapse of time
in South America.

When at Lima, I conversed on these subjects [3] with Mr. Gill, a civil
engineer, who had seen much of the interior country.  He told me that a
conjecture of a change of climate had sometimes crossed his mind; but
that he thought that the greater portion of land, now incapable of
cultivation, but covered with Indian ruins, had been reduced to this
state by the water-conduits, which the Indians formerly constructed on
so wonderful a scale, having been injured by neglect and by
subterranean movements.  I may here mention, that the Peruvians
actually carried their irrigating streams in tunnels through hills of
solid rock.  Mr. Gill told me, he had been employed professionally to
examine one: he found the passage low, narrow, crooked, and not of
uniform breadth, but of very considerable length.  Is it not most
wonderful that men should have attempted such operations, without the
use of iron or gunpowder?  Mr. Gill also mentioned to me a most
interesting, and, as far as I am aware, quite unparalleled case, of a
subterranean disturbance having changed the drainage of a country.
Travelling from Casma to Huaraz (not very far distant from Lima), he
found a plain covered with ruins and marks of ancient cultivation but
now quite barren.  Near it was the dry course of a considerable river,
whence the water for irrigation had formerly been conducted.  There was
nothing in the appearance of the water-course to indicate that the
river had not flowed there a few years previously; in some parts, beds
of sand and gravel were spread out; in others, the solid rock had been
worn into a broad channel, which in one spot was about 40 yards in
breadth and 8 feet deep.  It is self-evident that a person following up
the course of a stream, will always ascend at a greater or less
inclination: Mr. Gill, therefore, was much astonished, when walking up
the bed of this ancient river, to find himself suddenly going down
hill.  He imagined that the downward slope had a fall of about 40 or 50
feet perpendicular.  We here have unequivocal evidence that a ridge had
been uplifted right across the old bed of a stream.  From the moment
the river-course was thus arched, the water must necessarily have been
thrown back, and a new channel formed.  From that moment, also, the
neighbouring plain must have lost its fertilizing stream, and become a
desert.

June 27th.--We set out early in the morning, and by midday reached the
ravine of Paypote, where there is a tiny rill of water, with a little
vegetation, and even a few algarroba trees, a kind of mimosa. From
having firewood, a smelting-furnace had formerly been built here: we
found a solitary man in charge of it, whose sole employment was hunting
guanacos.  At night it froze sharply; but having plenty of wood for our
fire, we kept ourselves warm.

28th.--We continued gradually ascending, and the valley now changed
into a ravine.  During the day we saw several guanacos, and the track
of the closely-allied species, the Vicuna: this latter animal is
pre-eminently alpine in its habits; it seldom descends much below the
limit of perpetual snow, and therefore haunts even a more lofty and
sterile situation than the guanaco.  The only other animal which we saw
in any number was a small fox: I suppose this animal preys on the mice
and other small rodents, which, as long as there is the least
vegetation, subsist in considerable numbers in very desert places.  In
Patagonia, even on the borders of the salinas, where a drop of fresh
water can never be found, excepting dew, these little animals swarm.
Next to lizards, mice appear to be able to support existence on the
smallest and driest portions of the earth--even on islets in the midst
of great oceans.

The scene on all sides showed desolation, brightened and made palpable
by a clear, unclouded sky.  For a time such scenery is sublime, but
this feeling cannot last, and then it becomes uninteresting.  We
bivouacked at the foot of the "primera linea," or the first line of the
partition of waters. The streams, however, on the east side do not flow
to the Atlantic, but into an elevated district, in the middle of which
there is a large saline, or salt lake; thus forming a little Caspian
Sea at the height, perhaps, of ten thousand feet.  Where we slept,
there were some considerable patches of snow, but they do not remain
throughout the year.  The winds in these lofty regions obey very
regular laws. Ivery day a fresh breeze blows up the valley, and at
night, an hour or two after sunset, the air from the cold regions above
descends as through a funnel.  This night it blew a gale of wind, and
the temperature must have been considerably below the freezing-point,
for water in a vessel soon became a block of ice.  No clothes seemed to
oppose any obstacle to the air; I suffered very much from the cold, so
that I could not sleep, and in the morning rose with my body quite dull
and benumbed.

In the Cordillera further southward, people lose their lives from
snow-storms; here, it sometimes happens from another cause.  My guide,
when a boy of fourteen years old, was passing the Cordillera with a
party in the month of May; and while in the central parts, a furious
gale of wind arose, so that the men could hardly cling on their mules,
and stones were flying along the ground.  The day was cloudless, and
not a speck of snow fell, but the temperature was low.  It is probable
that the thermometer could not have stood very many degrees below the
freezing-point, but the effect on their bodies, ill protected by
clothing, must have been in proportion to the rapidity of the current
of cold air.  The gale lasted for more than a day; the men began to
lose their strength, and the mules would not move onwards.  My guide's
brother tried to return, but he perished, and his body was found two
years afterwards. Lying by the side of his mule near the road, with the
bridle still in his hand.  Two other men in the party lost their
fingers and toes; and out of two hundred mules and thirty cows, only
fourteen mules escaped alive.  Many years ago the whole of a large
party are supposed to have perished from a similar cause, but their
bodies to this day have never been discovered.  The union of a
cloudless sky, low temperature, and a furious gale of wind, must be, I
should think, in all parts of the world an unusual occurrence.

June 29th--We gladly travelled down the valley to our former night's
lodging, and thence to near the Agua amarga. On July 1st we reached the
valley of Copiapo.  The smell of the fresh clover was quite delightful,
after the scentless air of the dry, sterile Despoblado.  Whilst staying
in the town I heard an account from several of the inhabitants, of a
hill in the neighbourhood which they called "El Bramador,"--the roarer
or bellower.  I did not at the time pay sufficient attention to the
account; but, as far as I understood, the hill was covered by sand, and
the noise was produced only when people, by ascending it, put the sand
in motion.  The same circumstances are described in detail on the
authority of Seetzen and Ehrenberg, [4] as the cause of the sounds
which have been heard by many travellers on Mount Sinai near the Red
Sea.  One person with whom I conversed had himself heard the noise: he
described it as very surprising; and he distinctly stated that,
although he could not understand how it was caused, yet it was
necessary to set the sand rolling down the acclivity.  A horse walking
over dry coarse sand, causes a peculiar chirping noise from the
friction of the particles; a circumstance which I several times noticed
on the coast of Brazil.

Three days afterwards I heard of the Beagle's arrival at the Port,
distant eighteen leagues from the town.  There is very little land
cultivated down the valley; its wide expanse supports a wretched wiry
grass, which even the donkeys can hardly eat.  This poorness of the
vegetation is owing to the quantity of saline matter with which the
soil is impregnated. The Port consists of an assemblage of miserable
little hovels, situated at the foot of a sterile plain.  At present, as
the river contains water enough to reach the sea, the inhabitants enjoy
the advantage of having fresh water within a mile and a half.  On the
beach there were large piles of merchandise, and the little place had
an air of activity.  In the evening I gave my adios, with a hearty
good-will, to my companion Mariano Gonzales, with whom I had ridden so
many leagues in Chile.  The next morning the Beagle sailed for Iquique.

July 12th.--We anchored in the port of Iquique, in lat. 20 degs. 12',
on the coast of Peru.  The town contains about a thousand inhabitants,
and stands on a little plain of sand at the foot of a great wall of
rock, 2000 feet in height, here forming the coast.  The whole is
utterly desert.  A light shower of rain falls only once in very many
years; and the ravines consequently are filled with detritus, and the
mountain-sides covered by piles of fine white sand, even to a height of
a thousand feet.  During this season of the year a heavy bank of
clouds, stretched over the ocean, seldom rises above the wall of rocks
on the coast.  The aspect of the place was most gloomy; the little
port, with its few vessels, and small group of wretched houses, seemed
overwhelmed and out of all proportion with the rest of the scene.

The inhabitants live like persons on board a ship: every necessary
comes from a distance: water is brought in boats from Pisagua, about
forty miles northward, and is sold at the rate of nine reals (4s. 6d.)
an eighteen-gallon cask: I bought a wine-bottle full for threepence. In
like manner firewood, and of course every article of food, is imported.
Very few animals can be maintained in such a place: on the ensuing
morning I hired with difficulty, at the price of four pounds sterling,
two mules and a guide to take me to the nitrate of soda works.  These
are at present the support of Iquique.  This salt was first exported in
1830: in one year an amount in value of one hundred thousand pounds
sterling, was sent to France and England.  It is principally used as a
manure and in the manufacture of nitric acid: owing to its deliquescent
property it will not serve for gunpowder. Formerly there were two
exceedingly rich silver-mines in this neighbourhood, but their produce
is now very small.

Our arrival in the offing caused some little apprehension. Peru was in
a state of anarchy; and each party having demanded a contribution, the
poor town of Iquique was in tribulation, thinking the evil hour was
come.  The people had also their domestic troubles; a short time
before, three French carpenters had broken open, during the same night,
the two churches, and stolen all the plate: one of the robbers,
however, subsequently confessed, and the plate was recovered. The
convicts were sent to Arequipa, which though the capital of this
province, is two hundred leagues distant, the government there thought
it a pity to punish such useful workmen, who could make all sorts of
furniture; and accordingly liberated them.  Things being in this state,
the churches were again broken open, but this time the plate was not
recovered. The inhabitants became dreadfully enraged, and declaring
that none but heretics would thus "eat God Almighty," proceeded to
torture some Englishmen, with the intention of afterwards shooting
them.  At last the authorities interfered, and peace was established.


13th.--In the morning I started for the saltpetre-works, a distance of
fourteen leagues.  Having ascended the steep coast-mountains by a
zigzag sandy track, we soon came in view of the mines of Guantajaya and
St. Rosa.  These two small villages are placed at the very mouths of
the mines; and being perched up on hills, they had a still more
unnatural and desolate appearance than the town of Iquique.  We did not
reach the saltpetre-works till after sunset, having ridden all day
across an undulating country, a complete and utter desert.  The road
was strewed with the bones and dried skins of many beasts of burden
which had perished on it from fatigue.  Excepting the Vultur aura,
which preys on the carcasses, I saw neither bird, quadruped, reptile,
nor insect. On the coast-mountains, at the height of about 2000 feet
where during this season the clouds generally hang, a very few cacti
were growing in the clefts of rock; and the loose sand was strewed over
with a lichen, which lies on the surface quite unattached.  This plant
belongs to the genus Cladonia, and somewhat resembles the reindeer
lichen.  In some parts it was in sufficient quantity to tinge the sand,
as seen from a distance, of a pale yellowish colour.  Further inland,
during the whole ride of fourteen leagues, I saw only one other
vegetable production, and that was a most minute yellow lichen, growing
on the bones of the dead mules.  This was the first true desert which I
had seen: the effect on me was not impressive; but I believe this was
owing to my having become gradually accustomed to such scenes, as I
rode northward from Valparaiso, through Coquimbo, to Copiapo. The
appearance of the country was remarkable, from being covered by a thick
crust of common salt, and of a stratified saliferous alluvium, which
seems to have been deposited as the land slowly rose above the level of
the sea. The salt is white, very hard, and compact: it occurs in water
worn nodules projecting from the agglutinated sand, and is associated
with much gypsum.  The appearance of this superficial mass very closely
resembled that of a country after snow, before the last dirty patches
are thawed.  The existence of this crust of a soluble substance over
the whole face of the country, shows how extraordinarily dry the
climate must have been for a long period.

At night I slept at the house of the owner of one of the saltpetre
mines.  The country is here as unproductive as near the coast; but
water, having rather a bitter and brackish taste, can be procured by
digging wells.  The well at this house was thirty-six yards deep: as
scarcely any rain falls, it is evident the water is not thus derived;
indeed if it were, it could not fail to be as salt as brine, for the
whole surrounding country is incrusted with various saline substances.
We must therefore conclude that it percolates under ground from the
Cordillera, though distant many leagues.  In that direction there are a
few small villages, where the inhabitants, having more water, are
enabled to irrigate a little land, and raise hay, on which the mules
and asses, employed in carrying the saltpetre, are fed.  The nitrate of
soda was now selling at the ship's side at fourteen shillings per
hundred pounds: the chief expense is its transport to the sea-coast.
The mine consists of a hard stratum, between two and three feet thick,
of the nitrate mingled with a little of the sulphate of soda and a good
deal of common salt.  It lies close beneath the surface, and follows
for a length of one hundred and fifty miles the margin of a grand basin
or plain; this, from its outline, manifestly must once have been a
lake, or more probably an inland arm of the sea, as may be inferred
from the presence of iodic salts in the saline stratum.  The surface of
the plain is 3300 feet above the Pacific.


19th.--We anchored in the Bay of Callao, the seaport of Lima, the
capital of Peru.  We stayed here six weeks but from the troubled state
of public affairs, I saw very little of the country.  During our whole
visit the climate was far from being so delightful, as it is generally
represented.  A dull heavy bank of clouds constantly hung over the
land, so that during the first sixteen days I had only one view of the
Cordillera behind Lima.  These mountains, seen in stages, one above the
other, through openings in the clouds, had a very grand appearance.  It
is almost become a proverb, that rain never falls in the lower part of
Peru.  Yet this can hardly be considered correct; for during almost
every day of our visit there was a thick drizzling mist, which was
sufficient to make the streets muddy and one's clothes damp: this the
people are pleased to call Peruvian dew.  That much rain does not fall
is very certain, for the houses are covered only with flat roofs made
of hardened mud; and on the mole shiploads of wheat were piled up,
being thus left for weeks together without any shelter.

I cannot say I liked the very little I saw of Peru: in summer, however,
it is said that the climate is much pleasanter. In all seasons, both
inhabitants and foreigners suffer from severe attacks of ague.  This
disease is common on the whole coast of Peru, but is unknown in the
interior.  The attacks of illness which arise from miasma never fail to
appear most mysterious.  So difficult is it to judge from the aspect of
a country, whether or not it is healthy, that if a person had been told
to choose within the tropics a situation appearing favourable for
health, very probably he would have named this coast.  The plain round
the outskirts of Callao is sparingly covered with a coarse grass, and
in some parts there are a few stagnant, though very small, pools of
water.  The miasma, in all probability, arises from these: for the town
of Arica was similarly circumstanced, and its healthiness was much
improved by the drainage of some little pools.  Miasma is not always
produced by a luxuriant vegetation with an ardent climate; for many
parts of Brazil, even where there are marshes and a rank vegetation,
are much more healthy than this sterile coast of Peru.  The densest
forests in a temperate climate, as in Chiloe, do not seem in the
slightest degree to affect the healthy condition of the atmosphere.

The island of St. Jago, at the Cape de Verds, offers another strongly
marked instance of a country, which any one would have expected to find
most healthy, being very much the contrary.  I have described the bare
and open plains as supporting, during a few weeks after the rainy
season, a thin vegetation, which directly withers away and dries up: at
this period the air appears to become quite poisonous; both natives and
foreigners often being affected with violent fevers. On the other hand,
the Galapagos Archipelago, in the Pacific, with a similar soil, and
periodically subject to the same process of vegetation, is perfectly
healthy.  Humboldt has observed, that, "under the torrid zone, the
smallest marshes are the most dangerous, being surrounded, as at Vera
Cruz and Carthagena, with an arid and sandy soil, which raises the
temperature of the ambient air." [5] On the coast of Peru, however, the
temperature is not hot to any excessive degree; and perhaps in
consequence, the intermittent fevers are not of the most malignant
order.  In all unhealthy countries the greatest risk is run by sleeping
on shore.  Is this owing to the state of the body during sleep, or to a
greater abundance of miasma at such times?  It appears certain that
those who stay on board a vessel, though anchored at only a short
distance from the coast, generally suffer less than those actually on
shore.  On the other hand, I have heard of one remarkable case where a
fever broke out among the crew of a man-of-war some hundred miles off
the coast of Africa, and at the same time one of those fearful periods
[6] of death commenced at Sierra Leone.

No state in South America, since the declaration of independence, has
suffered more from anarchy than Peru.  At the time of our visit, there
were four chiefs in arms contending for supremacy in the government: if
one succeeded in becoming for a time very powerful, the others
coalesced against him; but no sooner were they victorious, than they
were again hostile to each other.  The other day, at the Anniversary of
the Independence, high mass was performed, the President partaking of
the sacrament: during the _Te Deum laudamus_, instead of each regiment
displaying the Peruvian flag, a black one with death's head was
unfurled.  Imagine a government under which such a scene could be
ordered, on such an occasion, to be typical of their determination of
fighting to death!  This state of affairs happened at a time very
unfortunately for me, as I was precluded from taking any excursions
much beyond the limits of the town.  The barren island of St. Lorenzo,
which forms the harbour, was nearly the only place where one could walk
securely.  The upper part, which is upwards of 1000 feet in height,
during this season of the year (winter), comes within the lower limit
of the clouds; and in consequence, an abundant cryptogamic vegetation,
and a few flowers cover the summit.  On the hills near Lima, at a
height but little greater, the ground is carpeted with moss, and beds
of beautiful yellow lilies, called Amancaes.  This indicates a very
much greater degree of humidity, than at a corresponding height at
Iquique. Proceeding northward of Lima, the climate becomes damper, till
on the banks of the Guayaquil, nearly under the equator, we find the
most luxuriant forests.  The change, however, from the sterile coast of
Peru to that fertile land is described as taking place rather abruptly
in the latitude of Cape Blanco, two degrees south of Guayaquil.

Callao is a filthy, ill-built, small seaport.  The inhabitants, both
here and at Lima, present every imaginable shade of mixture, between
European, Negro, and Indian blood.  They appear a depraved, drunken set
of people.  The atmosphere is loaded with foul smells, and that
peculiar one, which may be perceived in almost every town within the
tropics, was here very strong.  The fortress, which withstood Lord
Cochrane's long siege, has an imposing appearance.  But the President,
during our stay, sold the brass guns, and proceeded to dismantle parts
of it.  The reason assigned was, that he had not an officer to whom he
could trust so important a charge.  He himself had good reason for
thinking so, as he had obtained the presidentship by rebelling while in
charge of this same fortress.  After we left South America, he paid the
penalty in the usual manner, by being conquered, taken prisoner, and
shot.

Lima stands on a plain in a valley, formed during the gradual retreat
of the sea.  It is seven miles from Callao, and is elevated 500 feet
above it; but from the slope being very gradual, the road appears
absolutely level; so that when at Lima it is difficult to believe one
has ascended even one hundred feet: Humboldt has remarked on this
singularly deceptive case.  Steep barren hills rise like islands from
the plain, which is divided, by straight mud-walls, into large green
fields.  In these scarcely a tree grows excepting a few willows, and an
occasional clump of bananas and of oranges. The city of Lima is now in
a wretched state of decay: the streets are nearly unpaved; and heaps of
filth are piled up in all directions, where the black gallinazos, tame
as poultry, pick up bits of carrion.  The houses have generally an
upper story, built on account of the earthquakes, of plastered woodwork
but some of the old ones, which are now used by several families, are
immensely large, and would rival in suites of apartments the most
magnificent in any place.  Lima, the City of the Kings, must formerly
have been a splendid town. The extraordinary number of churches gives
it, even at the present day, a peculiar and striking character,
especially when viewed from a short distance.

One day I went out with some merchants to hunt in the immediate
vicinity of the city.  Our sport was very poor; but I had an
opportunity of seeing the ruins of one of the ancient Indian villages,
with its mound like a natural hill in the centre.  The remains of
houses, enclosures, irrigating streams, and burial mounds, scattered
over this plain, cannot fail to give one a high idea of the condition
and number of the ancient population.  When their earthenware, woollen
clothes, utensils of elegant forms cut out of the hardest rocks, tools
of copper, ornaments of precious stones, palaces, and hydraulic works,
are considered, it is impossible not to respect the considerable
advance made by them in the arts of civilization.  The burial mounds,
called Huacas, are really stupendous; although in some places they
appear to be natural hills incased and modelled.

There is also another and very different class of ruins, which
possesses some interest, namely, those of old Callao, overwhelmed by
the great earthquake of 1746, and its accompanying wave.  The
destruction must have been more complete even than at Talcahuano.
Quantities of shingle almost conceal the foundations of the walls, and
vast masses of brickwork appear to have been whirled about like pebbles
by the retiring waves.  It has been stated that the land subsided
during this memorable shock: I could not discover any proof of this;
yet it seems far from improbable, for the form of the coast must
certainly have undergone some change since the foundation of the old
town; as no people in their senses would willingly have chosen for
their building place, the narrow spit of shingle on which the ruins now
stand. Since our voyage, M. Tschudi has come to the conclusion, by the
comparison of old and modern maps, that the coast both north and south
of Lima has certainly subsided.

On the island of San Lorenzo, there are very satisfactory proofs of
elevation within the recent period; this of course is not opposed to
the belief, of a small sinking of the ground having subsequently taken
place.  The side of this island fronting the Bay of Callao, is worn
into three obscure terraces, the lower one of which is covered by a bed
a mile in length, almost wholly composed of shells of eighteen species,
now living in the adjoining sea.  The height of this bed is eighty-five
feet.  Many of the shells are deeply corroded, and have a much older
and more decayed appearance than those at the height of 500 or 600 feet
on the coast of Chile.  These shells are associated with much common
salt, a little sulphate of lime (both probably left by the evaporation
of the spray, as the land slowly rose), together with sulphate of soda
and muriate of lime.  They rest on fragments of the underlying
sandstone, and are covered by a few inches thick of detritus.  The
shells, higher up on this terrace could be traced scaling off in
flakes, and falling into an impalpable powder; and on an upper terrace,
at the height of 170 feet, and likewise at some considerably higher
points, I found a layer of saline powder of exactly similar appearance,
and lying in the same relative position.  I have no doubt that this
upper layer originally existed as a bed of shells, like that on the
eighty-five-feet ledge; but it does not now contain even a trace of
organic structure.  The powder has been analyzed for me by Mr. T.
Reeks; it consists of sulphates and muriates both of lime and soda,
with very little carbonate of lime.  It is known that common salt and
carbonate of lime left in a mass for some time together, partly
decompose each other; though this does not happen with small quantities
in solution.  As the half-decomposed shells in the lower parts are
associated with much common salt, together with some of the saline
substances composing the upper saline layer, and as these shells are
corroded and decayed in a remarkable manner, I strongly suspect that
this double decomposition has here taken place.  The resultant salts,
however, ought to be carbonate of soda and muriate of lime, the latter
is present, but not the carbonate of soda.  Hence I am led to imagine
that by some unexplained means, the carbonate of soda becomes changed
into the sulphate.  It is obvious that the saline layer could not have
been preserved in any country in which abundant rain occasionally fell:
on the other hand, this very circumstance, which at first sight appears
so highly favourable to the long preservation of exposed shells, has
probably been the indirect means, through the common salt not having
been washed away, of their decomposition and early decay.

I was much interested by finding on the terrace, at the height of
eighty-five feet, _embedded_  amidst the shells and much sea-drifted
rubbish, some bits of cotton thread, plaited rush, and the head of a
stalk of Indian corn: I compared these relics with similar ones taken
out of the Huacas, or old Peruvian tombs, and found them identical in
appearance. On the mainland in front of San Lorenzo, near Bellavista,
there is an extensive and level plain about a hundred feet high, of
which the lower part is formed of alternating layers of sand and impure
clay, together with some gravel, and the surface, to the depth of from
three to six feet, of a reddish loam, containing a few scattered
sea-shells and numerous small fragments of coarse red earthenware, more
abundant at certain spots than at others.  At first I was inclined to
believe that this superficial bed, from its wide extent and smoothness,
must have been deposited beneath the sea; but I afterwards found in one
spot, that it lay on an artificial floor of round stones.  It seems,
therefore, most probable that at a period when the land stood at a
lower level there was a plain very similar to that now surrounding
Callao, which being protected by a shingle beach, is raised but very
little above the level of the sea.  On this plain, with its underlying
red-clay beds, I imagine that the Indians manufactured their earthen
vessels; and that, during some violent earthquake, the sea broke over
the beach, and converted the plain into a temporary lake, as happened
round Callao in 1713 and 1746.  The water would then have deposited
mud, containing fragments of pottery from the kilns, more abundant at
some spots than at others, and shells from the sea. This bed, with
fossil earthenware, stands at about the same height with the shells on
the lower terrace of San Lorenzo, in which the cotton-thread and other
relics were embedded.

Hence we may safely conclude, that within the Indo-human period there
has been an elevation, as before alluded to, of more than eighty-five
feet; for some little elevation must have been lost by the coast having
subsided since the old maps were engraved.  At Valparaiso, although in
the 220 years before our visit, the elevation cannot have exceeded
nineteen feet, yet subsequently to 1817, there has been a rise, partly
insensible and partly by a start during the shock of 1822, of ten or
eleven feet.  The antiquity of the Indo-human race here, judging by the
eighty-five feet rise of the land since the relics were embedded, is
the more remarkable, as on the coast of Patagonia, when the land stood
about the same number of feet lower, the Macrauchenia was a living
beast; but as the Patagonian coast is some way distant from the
Cordillera, the rising there may have been slower than here. At Bahia
Blanca, the elevation has been only a few feet since the numerous
gigantic quadrupeds were there entombed; and, according to the
generally received opinion, when these extinct animals were living, man
did not exist. But the rising of that part of the coast of Patagonia,
is perhaps no way connected with the Cordillera, but rather with a line
of old volcanic rocks in Banda Oriental, so that it may have been
infinitely slower than on the shores of Peru. All these speculations,
however, must be vague; for who will pretend to say that there may not
have been several periods of subsidence, intercalated between the
movements of elevation; for we know that along the whole coast of
Patagonia, there have certainly been many and long pauses in the upward
action of the elevatory forces.

[1] Vol. iv. p. 11, and vol. ii. p. 217. For the remarks on Guayaquil,
see Silliman's Journ., vol. xxiv. p. 384.  For those on Tacna by Mr.
Hamilton, see Trans. of British Association, 1840.  For those on
Coseguina see Mr. Caldcleugh in Phil. Trans., 1835.  In the former
edition I collected several references on the coincidences between
sudden falls in the barometer and earthquakes; and between earthquakes
and meteors.

[2] Observa. sobre el Clima de Lima, p. 67.--Azara's Travels, vol. i.
p. 381.--Ulloa's Voyage, vol. ii. p. 28.--Burchell's Travels, vol. ii.
p. 524.--Webster's Description of the Azores, p. 124.--Voyage a l'Isle
de France par un Officer du Roi, tom. i. p. 248.--Description of St.
Helena, p. 123.

[3] Temple, in his travels through Upper Peru, or Bolivia, in going
from Potosi to Oruro, says, "I saw many Indian villages or dwellings in
ruins, up even to the very tops of the mountains, attesting a former
population where now all is desolate." He makes similar remarks in
another place; but I cannot tell whether this desolation has been
caused by a want of population, or by an altered condition of the land.

[4] Edinburgh, Phil. Journ., Jan., 1830, p. 74; and April, 1830, p.
258--also Daubeny on Volcanoes, p. 438; and Bengal Journ., vol. vii. p.
324.

[5] Political Essay on the Kingdom of New Spain, vol. iv. p. 199.

[6] A similar interesting case is recorded in the Madras Medical Quart.
Journ., 1839, p. 340.  Dr. Ferguson, in his admirable Paper (see 9th
vol. of Edinburgh Royal Trans.), shows clearly that the poison is
generated in the drying process; and hence that dry hot countries are
often the most unhealthy.



CHAPTER XVII

GALAPAGOS ARCHIPELAGO

The whole Group Volcanic--Numbers of Craters--Leafless Bushes Colony at
Charles Island--James Island--Salt-lake in Crater--Natural History of
the Group--Ornithology, curious Finches--Reptiles--Great Tortoises,
habits of--Marine Lizard, feeds on Sea-weed--Terrestrial Lizard,
burrowing habits, herbivorous--Importance of Reptiles in the
Archipelago--Fish, Shells, Insects--Botany--American Type of
Organization--Differences in the Species or Races on different
Islands--Tameness of the Birds--Fear of Man, an acquired Instinct.


SEPTEMBER 15th.--This archipelago consists of ten principal islands, of
which five exceed the others in size.  They are situated under the
Equator, and between five and six hundred miles westward of the coast
of America.  They are all formed of volcanic rocks; a few fragments of
granite curiously glazed and altered by the heat, can hardly be
considered as an exception.  Some of the craters, surmounting the
larger islands, are of immense size, and they rise to a height of
between three and four thousand feet.  Their flanks are studded by
innumerable smaller orifices.  I scarcely hesitate to affirm, that
there must be in the whole archipelago at least two thousand craters.
These consist either of lava or scoriae, or of finely-stratified,
sandstone-like tuff.  Most of the latter are beautifully symmetrical;
they owe their origin to eruptions of volcanic mud without any lava: it
is a remarkable circumstance that every one of the twenty-eight
tuff-craters which were examined, had their southern sides either much
lower than the other sides, or quite broken down and removed.  As all
these craters apparently have been formed when standing in the sea, and
as the waves from the trade wind and the swell from the open Pacific
here unite their forces on the southern coasts of all the islands, this
singular uniformity in the broken state of the craters, composed of the
soft and yielding tuff, is easily explained.

Considering that these islands are placed directly under the equator,
the climate is far from being excessively hot; this seems chiefly
caused by the singularly low temperature of the surrounding water,
brought here by the great southern


[map]


Polar current.  Excepting during one short season, very little rain
falls, and even then it is irregular; but the clouds generally hang
low.  Hence, whilst the lower parts of the islands are very sterile,
the upper parts, at a height of a thousand feet and upwards, possess a
damp climate and a tolerably luxuriant vegetation.  This is especially
the case on the windward sides of the islands, which first receive and
condense the moisture from the atmosphere.

In the morning (17th) we landed on Chatham Island, which, like the
others, rises with a tame and rounded outline, broken here and there by
scattered hillocks, the remains of former craters.  Nothing could be
less inviting than the first appearance.  A broken field of black
basaltic lava, thrown into the most rugged waves, and crossed by great
fissures, is everywhere covered by stunted, sun-burnt brushwood, which
shows little signs of life.  The dry and parched surface, being heated
by the noon-day sun, gave to the air a close and sultry feeling, like
that from a stove: we fancied even that the bushes smelt unpleasantly.
Although I diligently tried to collect as many plants as possible, I
succeeded in getting very few; and such wretched-looking little weeds
would have better become an arctic than an equatorial Flora.  The
brushwood appears, from a short distance, as leafless as our trees
during winter; and it was some time before I discovered that not only
almost every plant was now in full leaf, but that the greater number
were in flower. The commonest bush is one of the Euphorbiaceae: an
acacia and a great odd-looking cactus are the only trees which afford
any shade.  After the season of heavy rains, the islands are said to
appear for a short time partially green.  The volcanic island of
Fernando Noronha, placed in many respects under nearly similar
conditions, is the only other country where I have seen a vegetation at
all like this of the Galapagos Islands.

The Beagle sailed round Chatham Island, and anchored in several bays.
One night I slept on shore on a part of the island, where black
truncated cones were extraordinarily numerous: from one small eminence
I counted sixty of them, all surmounted by craters more or less
perfect.  The greater number consisted merely of a ring of red scoriae
or slags, cemented together: and their height above the plain of lava
was not more than from fifty to a hundred feet; none had been very
lately active.  The entire surface of this part of the island seems to
have been permeated, like a sieve, by the subterranean vapours: here
and there the lava, whilst soft, has been blown into great bubbles; and
in other parts, the tops of caverns similarly formed have fallen in,
leaving circular pits with steep sides.  From the regular form of the
many craters, they gave to the country an artificial appearance, which
vividly reminded me of those parts of Staffordshire, where the great
iron-foundries are most numerous. The day was glowing hot, and the
scrambling over the rough surface and through the intricate thickets,
was very fatiguing; but I was well repaid by the strange Cyclopean
scene. As I was walking along I met two large tortoises, each of which
must have weighed at least two hundred pounds: one was eating a piece
of cactus, and as I approached, it stared at me and slowly walked away;
the other gave a deep hiss, and drew in its head.  These huge reptiles,
surrounded by the black lava, the leafless shrubs, and large cacti,
seemed to my fancy like some antediluvian animals.  The few
dull-coloured birds cared no more for me than they did for the great
tortoises.

23rd.--The Beagle proceeded to Charles Island.  This archipelago has
long been frequented, first by the bucaniers, and latterly by whalers,
but it is only within the last six years, that a small colony has been
established here.  The inhabitants are between two and three hundred in
number; they are nearly all people of colour, who have been banished
for political crimes from the Republic of the Equator, of which Quito
is the capital.  The settlement is placed about four and a half miles
inland, and at a height probably of a thousand feet.  In the first part
of the road we passed through leafless thickets, as in Chatham Island.
Higher up, the woods gradually became greener; and as soon as we
crossed the ridge of the island, we were cooled by a fine southerly
breeze, and our sight refreshed by a green and thriving vegetation.  In
this upper region coarse grasses and ferns abound; but there are no
tree-ferns: I saw nowhere any member of the palm family, which is the
more singular, as 360 miles northward, Cocos Island takes its name from
the number of cocoa-nuts.  The houses are irregularly scattered over a
flat space of ground, which is cultivated with sweet potatoes and
bananas.  It will not easily be imagined how pleasant the sight of
black mud was to us, after having been so long, accustomed to the
parched soil of Peru and northern Chile.  The inhabitants, although
complaining of poverty, obtain, without much trouble, the means of
subsistence. In the woods there are many wild pigs and goats; but the
staple article of animal food is supplied by the tortoises.  Their
numbers have of course been greatly reduced in this island, but the
people yet count on two days' hunting giving them food for the rest of
the week.  It is said that formerly single vessels have taken away as
many as seven hundred, and that the ship's company of a frigate some
years since brought down in one day two hundred tortoises to the beach.

September  29th.--We doubled the south-west extremity of Albemarle
Island, and the next day were nearly becalmed between it and Narborough
Island.  Both are covered with immense deluges of black naked lava,
which have flowed either over the rims of the great caldrons, like
pitch over the rim of a pot in which it has been boiled, or have burst
forth from smaller orifices on the flanks; in their descent they have
spread over miles of the sea-coast.  On both of these islands,
eruptions are known to have taken place; and in Albemarle, we saw a
small jet of smoke curling from the summit of one of the great craters.
In the evening we anchored in Bank's Cove, in Albemarle Island.  The
next morning I went out walking.  To the south of the broken
tuff-crater, in which the Beagle was anchored, there was another
beautifully symmetrical one of an elliptic form; its longer axis was a
little less than a mile, and its depth about 500 feet.  At its bottom
there was a shallow lake, in the middle of which a tiny crater formed
an islet.  The day was overpoweringly hot, and the lake looked clear
and blue: I hurried down the cindery slope, and, choked with dust,
eagerly tasted the water--but, to my sorrow, I found it salt as brine.

The rocks on the coast abounded with great black lizards, between three
and four feet long; and on the hills, an ugly yellowish-brown species
was equally common.  We saw many of this latter kind, some clumsily
running out of the way, and others shuffling into their burrows.  I
shall presently describe in more detail the habits of both these
reptiles.  The whole of this northern part of Albemarle Island is
miserably sterile.

October 8th.--We arrived at James Island: this island, as well as
Charles Island, were long since thus named after our kings of the
Stuart line.  Mr. Bynoe, myself, and our servants were left here for a
week, with provisions and a tent, whilst the Beagle went for water.  We
found here a party of Spaniards, who had been sent from Charles Island
to dry fish, and to salt tortoise-meat.  About six miles inland, and at
the height of nearly 2000 feet, a hovel had been built in which two men
lived, who were employed in catching tortoises, whilst the others were
fishing on the coast.  I paid this party two visits, and slept there
one night.  As in the other islands, the lower region was covered by
nearly leafless bushes, but the trees were here of a larger growth than
elsewhere, several being two feet and some even two feet nine inches in
diameter.  The upper region being kept damp by the clouds, supports a
green and flourishing vegetation.  So damp was the ground, that there
were large beds of a coarse cyperus, in which great numbers of a very
small water-rail lived and bred.  While staying in this upper region,
we lived entirely upon tortoise-meat: the breast-plate roasted (as the
Gauchos do _carne con cuero_), with the flesh on it, is very good; and
the young tortoises make excellent soup; but otherwise the meat to my
taste is indifferent.

One day we accompanied a party of the Spaniards in their whale-boat to
a salina, or lake from which salt is procured.  After landing, we had a
very rough walk over a rugged field of recent lava, which has almost
surrounded a tuff-crater, at the bottom of which the salt-lake lies.
The water is only three or four inches deep, and rests on a layer of
beautifully crystallized, white salt.  The lake is quite circular, and
is fringed with a border of bright green succulent plants; the almost
precipitous walls of the crater are clothed with wood, so that the
scene was altogether both picturesque and curious.  A few years since,
the sailors belonging to a sealing-vessel murdered their captain in
this quiet spot; and we saw his skull lying among the bushes.

During the greater part of our stay of a week, the sky was cloudless,
and if the trade-wind failed for an hour, the heat became very
oppressive.  On two days, the thermometer within the tent stood for
some hours at 93 degs.; but in the open air, in the wind and sun, at
only 85 degs.  The sand was extremely hot; the thermometer placed in
some of a brown colour immediately rose to 137 degs., and how much
above that it would have risen, I do not know, for it was not graduated
any higher.  The black sand felt much hotter, so that even in thick
boots it was quite disagreeable to walk over it.


The natural history of these islands is eminently curious, and well
deserves attention.  Most of the organic productions are aboriginal
creations, found nowhere else; there is even a difference between the
inhabitants of the different islands; yet all show a marked
relationship with those of America, though separated from that
continent by an open space of ocean, between 500 and 600 miles in
width.  The archipelago is a little world within itself, or rather a
satellite attached to America, whence it has derived a few stray
colonists, and has received the general character of its indigenous
productions.  Considering the small size of the islands, we feel the
more astonished at the number of their aboriginal beings, and at their
confined range.  Seeing every height crowned with its crater, and the
boundaries of most of the lava-streams still distinct, we are led to
believe that within a period geologically recent the unbroken ocean was
here spread out.  Hence, both in space and time, we seem to be brought
somewhat near to that great fact--that mystery of mysteries--the first
appearance of new beings on this earth.

Of terrestrial mammals, there is only one which must be considered as
indigenous, namely, a mouse (Mus Galapagoensis), and this is confined,
as far as I could ascertain, to Chatham Island, the most easterly
island of the group.  It belongs, as I am informed by Mr. Waterhouse,
to a division of the family of mice characteristic of America.  At
James Island, there is a rat sufficiently distinct from the common kind
to have been named and described by Mr. Waterhouse; but as it belongs
to the old-world division of the family, and as this island has been
frequented by ships for the last hundred and fifty years, I can hardly
doubt that this rat is merely a variety produced by the new and
peculiar climate, food, and soil, to which it has been subjected.
Although no one has a right to speculate without distinct facts, yet
even with respect to the Chatham Island mouse, it should be borne in
mind, that it may possibly be an American species imported here; for I
have seen, in a most unfrequented part of the Pampas, a native mouse
living in the roof of a newly built hovel, and therefore its
transportation in a vessel is not improbable: analogous facts have been
observed by Dr. Richardson in North America.

Of land-birds I obtained twenty-six kinds, all peculiar to the group
and found nowhere else, with the exception of one lark-like finch from
North America (Dolichonyx oryzivorus), which ranges on that continent
as far north as 54 degs., and generally frequents marshes.  The other
twenty-five birds consist, firstly, of a hawk, curiously intermediate
in structure between a buzzard and the American group of
carrion-feeding Polybori; and with these latter birds it agrees most
closely in every habit and even tone of voice.  Secondly, there are two
owls, representing the short-eared and white barn-owls of Europe.
Thirdly, a wren, three tyrant-flycatchers (two of them species of
Pyrocephalus, one or both of which would be ranked by some
ornithologists as only varieties), and a dove--all analogous to, but
distinct from, American species.  Fourthly, a swallow, which though
differing from the Progne purpurea of both Americas, only in being
rather duller colored, smaller, and slenderer, is considered by Mr.
Gould as specifically distinct.  Fifthly, there are three species of
mocking thrush--a form highly characteristic of America.  The remaining
land-birds form a most singular group of finches, related to each other
in the structure of their beaks, short tails, form of body and plumage:
there are thirteen species, which Mr. Gould has divided into four
sub-groups.  All these species are peculiar to this archipelago; and so
is the whole group, with the exception of one species of the sub-group
Cactornis, lately brought from Bow Island, in the Low Archipelago.  Of
Cactornis, the two species may be often seen climbing about the flowers
of the great cactus-trees; but all the other species of this group of
finches, mingled together in flocks, feed on the dry and sterile ground
of the lower districts.  The males of all, or certainly of the greater
number, are jet black; and the females (with perhaps one or two
exceptions) are brown.  The most curious fact is the perfect gradation
in the size of the beaks in the different species of Geospiza, from one
as large as that of a hawfinch to that of a chaffinch, and (if Mr.
Gould is right in including his sub-group, Certhidea, in the main
group) even to that of a warbler.  The largest beak in the genus
Geospiza is shown in Fig. 1, and the smallest in Fig. 3; but instead of
there being only one intermediate species, with a beak of the size
shown in Fig. 2, there are no less than six species with insensibly
graduated beaks.  The beak of the sub-group Certhidea, is shown in Fig.
4.  The beak of Cactornis is


[picture]

1. Geospiza magnirostris.      2. Geospiza fortis. 3. Geospiza parvula.
4. Certhidea olivasea.


somewhat like that of a starling, and that of the fourth sub-group,
Camarhynchus, is slightly parrot-shaped.  Seeing this gradation and
diversity of structure in one small, intimately related group of birds,
one might really fancy that from an original paucity of birds in this
archipelago, one species had been taken and modified for different
ends.  In a like manner it might be fancied that a bird originally a
buzzard, had been induced here to undertake the office of the
carrion-feeding Polybori of the American continent.

Of waders and water-birds I was able to get only eleven kinds, and of
these only three (including a rail confined to the damp summits of the
islands) are new species.  Considering the wandering habits of the
gulls, I was surprised to find that the species inhabiting these
islands is peculiar, but allied to one from the southern parts of South
America. The far greater peculiarity of the land-birds, namely,
twenty-five out of twenty-six, being new species, or at least new
races, compared with the waders and web-footed birds, is in accordance
with the greater range which these latter orders have in all parts of
the world.  We shall hereafter see this law of aquatic forms, whether
marine or fresh-water, being less peculiar at any given point of the
earth's surface than the terrestrial forms of the same classes,
strikingly illustrated in the shells, and in a lesser degree in the
insects of this archipelago.

Two of the waders are rather smaller than the same species brought from
other places: the swallow is also smaller, though it is doubtful
whether or not it is distinct from its analogue.  The two owls, the two
tyrant-catchers (Pyrocephalus) and the dove, are also smaller than the
analogous but distinct species, to which they are most nearly related;
on the other hand, the gull is rather larger.  The two owls, the
swallow, all three species of mocking-thrush, the dove in its separate
colours though not in its whole plumage, the Totanus, and the gull, are
likewise duskier coloured than their analogous species; and in the case
of the mocking-thrush and Totanus, than any other species of the two
genera. With the exception of a wren with a fine yellow breast, and of
a tyrant-flycatcher with a scarlet tuft and breast, none of the birds
are brilliantly coloured, as might have been expected in an equatorial
district.  Hence it would appear probable, that the same causes which
here make the immigrants of some peculiar species smaller, make most of
the peculiar Galapageian species also smaller, as well as very
generally more dusky coloured.  All the plants have a wretched, weedy
appearance, and I did not see one beautiful flower.  The insects,
again, are small-sized and dull-coloured, and, as Mr. Waterhouse
informs me, there is nothing in their general appearance which would
have led him to imagine that they had come from under the equator. [1]
The birds, plants, and insects have a desert character, and are not
more brilliantly coloured than those from southern Patagonia; we may,
therefore, conclude that the usual gaudy colouring of the intertropical
productions, is not related either to the heat or light of those zones,
but to some other cause, perhaps to the conditions of existence being
generally favourable to life.


We will now turn to the order of reptiles, which gives the most
striking character to the zoology of these islands. The species are not
numerous, but the numbers of individuals of each species are
extraordinarily great.  There is one small lizard belonging to a South
American genus, and two species (and probably more) of the
Amblyrhynchus--a genus confined to the Galapagos Islands.  There is one
snake which is numerous; it is identical, as I am informed by M.
Bibron, with the Psammophis Temminckii from Chile. [2] Of sea-turtle I
believe there are more than one species, and of tortoises there are, as
we shall presently show, two or three species or races.  Of toads and
frogs there are none: I was surprised at this, considering how well
suited for them the temperate and damp upper woods appeared to be.  It
recalled to my mind the remark made by Bory St. Vincent, [3] namely,
that none of this family are found on any of the volcanic islands in
the great oceans.  As far as I can ascertain from various works, this
seems to hold good throughout the Pacific, and even in the large
islands of the Sandwich archipelago.  Mauritius offers an apparent
exception, where I saw the Rana Mascariensis in abundance: this frog is
said now to inhabit the Seychelles, Madagascar, and Bourbon; but on the
other hand, Du Bois, in his voyage in 1669, states that there were no
reptiles in Bourbon except tortoises; and the Officier du Roi asserts
that before 1768 it had been attempted, without success, to introduce
frogs into Mauritius--I presume for the purpose of eating: hence it may
be well doubted whether this frog is an aboriginal of these islands.
The absence of the frog family in the oceanic islands is the more
remarkable, when contrasted with the case of lizards, which swarm on
most of the smallest islands.  May this difference not be caused, by
the greater facility with which the eggs of lizards, protected by
calcareous shells might be transported through salt-water, than could
the slimy spawn of frogs?

I will first describe the habits of the tortoise (Testudo nigra,
formerly called Indica), which has been so frequently alluded to. These
animals are found, I believe, on all the islands of the archipelago;
certainly on the greater number. They frequent in preference the high
damp parts, but they likewise live in the lower and arid districts.  I
have already shown, from the numbers which have been caught in a single
day, how very numerous they must be.  Some grow to an immense size: Mr.
Lawson, an Englishman, and vice-governor of the colony, told us that he
had seen several so large, that it required six or eight men to lift
them from the ground; and that some had afforded as much as two hundred
pounds of meat.  The old males are the largest, the females rarely
growing to so great a size: the male can readily be distinguished from
the female by the greater length of its tail.  The tortoises which live
on those islands where there is no water, or in the lower and arid
parts of the others, feed chiefly on the succulent cactus.  Those which
frequent the higher and damp regions, eat the leaves of various trees,
a kind of berry (called guayavita) which is acid and austere, and
likewise a pale green filamentous lichen (Usnera plicata), that hangs
from the boughs of the trees.

The tortoise is very fond of water, drinking large quantities, and
wallowing in the mud.  The larger islands alone possess springs, and
these are always situated towards the central parts, and at a
considerable height.  The tortoises, therefore, which frequent the
lower districts, when thirsty, are obliged to travel from a long
distance.  Hence broad and well-beaten paths branch off in every
direction from the wells down to the sea-coast; and the Spaniards by
following them up, first discovered the watering-places.  When I landed
at Chatham Island, I could not imagine what animal travelled so
methodically along well-chosen tracks.  Near the springs it was a
curious spectacle to behold many of these huge creatures, one set
eagerly travelling onwards with outstretched necks, and another set
returning, after having drunk their fill.  When the tortoise arrives at
the spring, quite regardless of any spectator, he buries his head in
the water above his eyes, and greedily swallows great mouthfuls, at the
rate of about ten in a minute.  The inhabitants say each animal stays
three or four days in the neighbourhood of the water, and then returns
to the lower country; but they differed respecting the frequency of
these visits.  The animal probably regulates them according to the
nature of the food on which it has lived.  It is, however, certain,
that tortoises can subsist even on these islands where there is no
other water than what falls during a few rainy days in the year.

I believe it is well ascertained, that the bladder of the frog acts as
a reservoir for the moisture necessary to its existence: such seems to
be the case with the tortoise.  For some time after a visit to the
springs, their urinary bladders are distended with fluid, which is said
gradually to decrease in volume, and to become less pure.  The
inhabitants, when walking in the lower district, and overcome with
thirst, often take advantage of this circumstance, and drink the
contents of the bladder if full: in one I saw killed, the fluid was
quite limpid, and had only a very slightly bitter taste.  The
inhabitants, however, always first drink the water in the pericardium,
which is described as being best.

The tortoises, when purposely moving towards any point, travel by night
and day, and arrive at their journey's end much sooner than would be
expected.  The inhabitants, from observing marked individuals, consider
that they travel a distance of about eight miles in two or three days.
One large tortoise, which I watched, walked at the rate of sixty yards
in ten minutes, that is 360 yards in the hour, or four miles a
day,--allowing a little time for it to eat on the road.  During the
breeding season, when the male and female are together, the male utters
a hoarse roar or bellowing, which, it is said, can be heard at the
distance of more than a hundred yards. The female never uses her voice,
and the male only at these times; so that when the people hear this
noise, they know that the two are together.  They were at this time
(October) laying their eggs.  The female, where the soil is sandy,
deposits them together, and covers them up with sand; but where the
ground is rocky she drops them indiscriminately in any hole: Mr. Bynoe
found seven placed in a fissure.  The egg is white and spherical; one
which I measured was seven inches and three-eighths in circumference,
and therefore larger than a hen's egg.  The young tortoises, as soon as
they are hatched, fall a prey in great numbers to the carrion-feeding
buzzard.  The old ones seem generally to die from accidents, as from
falling down precipices: at least, several of the inhabitants told me,
that they never found one dead without some evident cause.

The inhabitants believe that these animals are absolutely deaf;
certainly they do not overhear a person walking close behind them.  I
was always amused when overtaking one of these great monsters, as it
was quietly pacing along, to see how suddenly, the instant I passed, it
would draw in its head and legs, and uttering a deep hiss fall to the
ground with a heavy sound, as if struck dead.  I frequently got on
their backs, and then giving a few raps on the hinder part of their
shells, they would rise up and walk away;--but I found it very
difficult to keep my balance.  The flesh of this animal is largely
employed, both fresh and salted; and a beautifully clear oil is
prepared from the fat.  When a tortoise is caught, the man makes a slit
in the skin near its tail, so as to see inside its body, whether the
fat under the dorsal plate is thick.  If it is not, the animal is
liberated and it is said to recover soon from this strange operation.
In order to secure the tortoise, it is not sufficient to turn them like
turtle, for they are often able to get on their legs again.

There can be little doubt that this tortoise is an aboriginal
inhabitant of the Galapagos; for it is found on all, or nearly all, the
islands, even on some of the smaller ones where there is no water; had
it been an imported species, this would hardly have been the case in a
group which has been so little frequented.  Moreover, the old Bucaniers
found this tortoise in greater numbers even than at present: Wood and
Rogers also, in 1708, say that it is the opinion of the Spaniards, that
it is found nowhere else in this quarter of the world.  It is now
widely distributed; but it may be questioned whether it is in any other
place an aboriginal.  The bones of a tortoise at Mauritius, associated
with those of the extinct Dodo, have generally been considered as
belonging to this tortoise; if this had been so, undoubtedly it must
have been there indigenous; but M. Bibron informs me that he believes
that it was distinct, as the species now living there certainly is.

The Amblyrhynchus, a remarkable genus of lizards, is confined to this
archipelago; there are two species, resembling

[picture]

each other in general form, one being terrestrial and the other
aquatic.  This latter species (A. cristatus) was first characterized by
Mr. Bell, who well foresaw, from its short, broad head, and strong
claws of equal length, that its habits of life would turn out very
peculiar, and different from those of its nearest ally, the Iguana.  It
is extremely common on all the islands throughout the group, and lives
exclusively on the rocky sea-beaches, being never found, at least I
never saw one, even ten yards in-shore.  It is a hideous-looking
creature, of a dirty black colour, stupid, and sluggish in its
movements. The usual length of a full-grown one is about a yard, but
there are some even four feet long; a large one weighed twenty pounds:
on the island of Albemarle they seem to grow to a greater size than
elsewhere.  Their tails are flattened sideways, and all four feet
partially webbed.  They are occasionally seen some hundred yards from
the shore, swimming about; and Captain Collnett, in his Voyage says,
"They go to sea in herds a-fishing, and sun themselves on the rocks;
and may be called alligators in miniature." It must not, however, be
supposed that they live on fish.  When in the water this lizard swims
with perfect ease and quickness, by a serpentine movement of its body
and flattened tail--the legs being motionless and closely collapsed on
its sides. A seaman on board sank one, with a heavy weight attached to
it, thinking thus to kill it directly; but when, an hour afterwards, he
drew up the line, it was quite active.  Their limbs and strong claws
are admirably adapted for crawling over the rugged and fissured masses
of lava, which everywhere form the coast.  In such situations, a group
of six or seven of these hideous reptiles may oftentimes be seen on the
black rocks, a few feet above the surf, basking in the sun with
outstretched legs.

I opened the stomachs of several, and found them largely distended with
minced sea-weed (Ulvae), which grows in thin foliaceous expansions of a
bright green or a dull red colour.  I do not recollect having observed
this sea-weed in any quantity on the tidal rocks; and I have reason to
believe it grows at the bottom of the sea, at some little distance from
the coast.  If such be the case, the object of these animals
occasionally going out to sea is explained.  The stomach contained
nothing but the sea-weed.  Mr. Baynoe, however, found a piece of crab
in one; but this might have got in accidentally, in the same manner as
I have seen a caterpillar, in the midst of some lichen, in the paunch
of a tortoise.  The intestines were large, as in other herbivorous
animals.  The nature of this lizard's food, as well as the structure of
its tail and feet, and the fact of its having been seen voluntarily
swimming out at sea, absolutely prove its aquatic habits; yet there is
in this respect one strange anomaly, namely, that when frightened it
will not enter the water.  Hence it is easy to drive these lizards down
to any little point overhanging the sea, where they will sooner allow a
person to catch hold of their tails than jump into the water.  They do
not seem to have any notion of biting; but when much frightened they
squirt a drop of fluid from each nostril.  I threw one several times as
far as I could, into a deep pool left by the retiring tide; but it
invariably returned in a direct line to the spot where I stood.  It
swam near the bottom, with a very graceful and rapid movement, and
occasionally aided itself over the uneven ground with its feet.  As
soon as it arrived near the edge, but still being under water, it tried
to conceal itself in the tufts of sea-weed, or it entered some crevice.
As soon as it thought the danger was past, it crawled out on the dry
rocks, and shuffled away as quickly as it could.  I several times
caught this same lizard, by driving it down to a point, and though
possessed of such perfect powers of diving and swimming, nothing would
induce it to enter the water; and as often as I threw it in, it
returned in the manner above described.  Perhaps this singular piece of
apparent stupidity may be accounted for by the circumstance, that this
reptile has no enemy whatever on shore, whereas at sea it must often
fall a prey to the numerous sharks.  Hence, probably, urged by a fixed
and hereditary instinct that the shore is its place of safety, whatever
the emergency may be, it there takes refuge.

During our visit (in October), I saw extremely few small individuals of
this species, and none I should think under a year old.  From this
circumstance it seems probable that the breeding season had not then
commenced.  I asked several of the inhabitants if they knew where it
laid its eggs: they said that they knew nothing of its propagation,
although well acquainted with the eggs of the land kind--a fact,
considering how very common this lizard is, not a little extraordinary.

We will now turn to the terrestrial species (A. Demarlii), with a round
tail, and toes without webs.  This lizard, instead of being found like
the other on all the islands, is confined to the central part of the
archipelago, namely to Albemarle, James, Barrington, and Indefatigable
islands.  To the southward, in Charles, Hood, and Chatham islands, and
to the northward, in Towers, Bindloes, and Abingdon, I neither saw nor
heard of any.  It would appear as if it had been created in the centre
of the archipelago, and thence had been dispersed only to a certain
distance.  Some of these lizards inhabit the high and damp parts of the
islands, but they are much more numerous in the lower and sterile
districts near the coast.  I cannot give a more forcible proof of their
numbers, than by stating that when we were left at James Island, we
could not for some time find a spot free from their burrows on which to
pitch our single tent.  Like their brothers the sea-kind, they are ugly
animals, of a yellowish orange beneath, and of a brownish red colour
above: from their low facial angle they have a singularly stupid
appearance.  They are, perhaps, of a rather less size than the marine
species; but several of them weighed between ten and fifteen pounds. In
their movements they are lazy and half torpid.  When not frightened,
they slowly crawl along with their tails and bellies dragging on the
ground.  They often stop, and doze for a minute or two, with closed
eyes and hind legs spread out on the parched soil.

They inhabit burrows, which they sometimes make between fragments of
lava, but more generally on level patches of the soft sandstone-like
tuff.  The holes do not appear to be very deep, and they enter the
ground at a small angle; so that when walking over these
lizard-warrens, the soil is constantly giving way, much to the
annoyance of the tired walker.  This animal, when making its burrow,
works alternately the opposite sides of its body.  One front leg for a
short time scratches up the soil, and throws it towards the hind foot,
which is well placed so as to heave it beyond the mouth of the hole.
That side of the body being tired, the other takes up the task, and so
on alternately.  I watched one for a long time, till half its body was
buried; I then walked up and pulled it by the tail, at this it was
greatly astonished, and soon shuffled up to see what was the matter;
and then stared me in the face, as much as to say, "What made you pull
my tail?"

They feed by day, and do not wander far from their burrows; if
frightened, they rush to them with a most awkward gait.  Except when
running down hill, they cannot move very fast, apparently from the
lateral position of their legs. They are not at all timorous: when
attentively watching any one, they curl their tails, and, raising
themselves on their front legs, nod their heads vertically, with a
quick movement, and try to look very fierce; but in reality they are
not at all so: if one just stamps on the ground, down go their tails,
and off they shuffle as quickly as they can.  I have frequently
observed small fly-eating lizards, when watching anything, nod their
heads in precisely the same manner; but I do not at all know for what
purpose.  If this Amblyrhynchus is held and plagued with a stick, it
will bite it very severely; but I caught many by the tail, and they
never tried to bite me. If two are placed on the ground and held
together, they will fight, and bite each other till blood is drawn.

The individuals, and they are the greater number, which inhabit the
lower country, can scarcely taste a drop of water throughout the year;
but they consume much of the succulent cactus, the branches of which
are occasionally broken off by the wind.  I several times threw a piece
to two or three of them when together; and it was amusing enough to see
them trying to seize and carry it away in their mouths, like so many
hungry dogs with a bone.  They eat very deliberately, but do not chew
their food.  The little birds are aware how harmless these creatures
are: I have seen one of the thick-billed finches picking at one end of
a piece of cactus (which is much relished by all the animals of the
lower region), whilst a lizard was eating at the other end; and
afterwards the little bird with the utmost indifference hopped on the
back of the reptile.

I opened the stomachs of several, and found them full of vegetable
fibres and leaves of different trees, especially of an acacia.  In the
upper region they live chiefly on the acid and astringent berries of
the guayavita, under which trees I have seen these lizards and the huge
tortoises feeding together.  To obtain the acacia-leaves they crawl up
the low stunted trees; and it is not uncommon to see a pair quietly
browsing, whilst seated on a branch several feet above the ground.
These lizards, when cooked, yield a white meat, which is liked by those
whose stomachs soar above all prejudices.

Humboldt has remarked that in intertropical South America, all lizards
which inhabit dry regions are esteemed delicacies for the table.  The
inhabitants state that those which inhabit the upper damp parts drink
water, but that the others do not, like the tortoises, travel up for it
from the lower sterile country.  At the time of our visit, the females
had within their bodies numerous, large, elongated eggs, which they lay
in their burrows: the inhabitants seek them for food.

These two species of Amblyrhynchus agree, as I have already stated, in
their general structure, and in many of their habits.  Neither have
that rapid movement, so characteristic of the genera Lacerta and
Iguana.  They are both herbivorous, although the kind of vegetation on
which they feed is so very different.  Mr. Bell has given the name to
the genus from the shortness of the snout: indeed, the form of the
mouth may almost be compared to that of the tortoise: one is led to
suppose that this is an adaptation to their herbivorous appetites.  It
is very interesting thus to find a well-characterized genus, having its
marine and terrestrial species, belonging to so confined a portion of
the world.  The aquatic species is by far the most remarkable, because
it is the only existing lizard which lives on marine vegetable
productions.  As I at first observed, these islands are not so
remarkable for the number of the species of reptiles, as for that of
the individuals, when we remember the well-beaten paths made by the
thousands of huge tortoises--the many turtles--the great warrens of the
terrestrial Amblyrhynchus--and the groups of the marine species basking
on the coast-rocks of every island--we must admit that there is no
other quarter of the world where this Order replaces the herbivorous
mammalia in so extraordinary a manner.  The geologist on hearing this
will probably refer back in his mind to the Secondary epochs, when
lizards, some herbivorous, some carnivorous, and of dimensions
comparable only with our existing whales, swarmed on the land and in
the sea.  It is, therefore, worthy of his observation, that this
archipelago, instead of possessing a humid climate and rank vegetation,
cannot be considered otherwise than extremely arid, and, for an
equatorial region, remarkably temperate.

To finish with the zoology: the fifteen kinds of sea-fish which I
procured here are all new species; they belong to twelve genera, all
widely distributed, with the exception of Prionotus, of which the four
previously known species live on the eastern side of America.  Of
land-shells I collected sixteen kinds (and two marked varieties), of
which, with the exception of one Helix found at Tahiti, all are
peculiar to this archipelago: a single fresh-water shell (Paludina) is
common to Tahiti and Van Diemen's Land.  Mr. Cuming, before our voyage
procured here ninety species of sea-shells, and this does not include
several species not yet specifically examined, of Trochus, Turbo,
Monodonta, and Nassa.  He has been kind enough to give me the following
interesting results: Of the ninety shells, no less than forty-seven are
unknown elsewhere--a wonderful fact, considering how widely distributed
sea-shells generally are.  Of the forty-three shells found in other
parts of the world, twenty-five inhabit the western coast of America,
and of these eight are distinguishable as varieties; the remaining
eighteen (including one variety) were found by Mr. Cuming in the Low
Archipelago, and some of them also at the Philippines.  This fact of
shells from islands in the central parts of the Pacific occurring here,
deserves notice, for not one single sea-shell is known to be common to
the islands of that ocean and to the west coast of America.  The space
of open sea running north and south off the west coast, separates two
quite distinct conchological provinces; but at the Galapagos
Archipelago we have a halting-place, where many new forms have been
created, and whither these two great conchological provinces have each
sent up several colonists.  The American province has also sent here
representative species; for there is a Galapageian species of
Monoceros, a genus only found on the west coast of America; and there
are Galapageian species of Fissurella and Cancellaria, genera common on
the west coast, but not found (as I am informed by Mr. Cuming) in the
central islands of the Pacific.  On the other hand, there are
Galapageian species of Oniscia and Stylifer, genera common to the West
Indies and to the Chinese and Indian seas, but not found either on the
west coast of America or in the central Pacific.  I may here add, that
after the comparison by Messrs. Cuming and Hinds of about 2000 shells
from the eastern and western coasts of America, only one single shell
was found in common, namely, the Purpura patula, which inhabits the
West Indies, the coast of Panama, and the Galapagos.  We have,
therefore, in this quarter of the world, three great conchological
sea-provinces, quite distinct, though surprisingly near each other,
being separated by long north and south spaces either of land or of
open sea.

I took great pains in collecting the insects, but excepting Tierra del
Fuego, I never saw in this respect so poor a country. Even in the upper
and damp region I procured very few, excepting some minute Diptera and
Hymenoptera, mostly of common mundane forms.  As before remarked, the
insects, for a tropical region, are of very small size and dull
colours. Of beetles I collected twenty-five species (excluding a
Dermestes and Corynetes imported, wherever a ship touches); of these,
two belong to the Harpalidae, two to the Hydrophilidae, nine to three
families of the Heteromera, and the remaining twelve to as many
different families.  This circumstance of insects (and I may add
plants), where few in number, belonging to many different families, is,
I believe, very general.  Mr. Waterhouse, who has published [4] an
account of the insects of this archipelago, and to whom I am indebted
for the above details, informs me that there are several new genera:
and that of the genera not new, one or two are American, and the rest
of mundane distribution. With the exception of a wood-feeding Apate,
and of one or probably two water-beetles from the American continent,
all the species appear to be new.

The botany of this group is fully as interesting as the zoology.  Dr.
J. Hooker will soon publish in the "Linnean Transactions" a full
account of the Flora, and I am much indebted to him for the following
details.  Of flowering plants there are, as far as at present is known,
185 species, and 40 cryptogamic species, making altogether 225; of this
number I was fortunate enough to bring home 193.  Of the flowering
plants, 100 are new species, and are probably confined to this
archipelago.  Dr. Hooker conceives that, of the plants not so confined,
at least 10 species found near the cultivated ground at Charles Island,
have been imported. It is, I think, surprising that more American
species have not been introduced naturally, considering that the
distance is only between 500 and 600 miles from the continent, and that
(according to Collnet, p. 58) drift-wood, bamboos, canes, and the nuts
of a palm, are often washed on the south-eastern shores.  The
proportion of 100 flowering plants out of 183 (or 175 excluding the
imported weeds) being new, is sufficient, I conceive, to make the
Galapagos Archipelago a distinct botanical province; but this Flora is
not nearly so peculiar as that of St. Helena, nor, as I am informed by
Dr. Hooker, of Juan Fernandez.  The peculiarity of the Galapageian
Flora is best shown in certain families;--thus there are 21 species of
Compositae, of which 20 are peculiar to this archipelago; these belong
to twelve genera, and of these genera no less than ten are confined to
the archipelago! Dr. Hooker informs me that the Flora has an
undoubtedly Western American character; nor can he detect in it any
affinity with that of the Pacific.  If, therefore, we except the
eighteen marine, the one fresh-water, and one land-shell, which have
apparently come here as colonists from the central islands of the
Pacific, and likewise the one distinct Pacific species of the
Galapageian group of finches, we see that this archipelago, though
standing in the Pacific Ocean, is zoologically part of America.

If this character were owing merely to immigrants from America, there
would be little remarkable in it; but we see that a vast majority of
all the land animals, and that more than half of the flowering plants,
are aboriginal productions It was most striking to be surrounded by new
birds, new reptiles, new shells, new insects, new plants, and yet by
innumerable trifling details of structure, and even by the tones of
voice and plumage of the birds, to have the temperate plains of
Patagonia, or rather the hot dry deserts of Northern Chile, vividly
brought before my eyes.  Why, on these small points of land, which
within a late geological period must have been covered by the ocean,
which are formed by basaltic lava, and therefore differ in geological
character from the American continent, and which are placed under a
peculiar climate,--why were their aboriginal inhabitants, associated, I
may add, in different proportions both in kind and number from those on
the continent, and therefore acting on each other in a different
manner--why were they created on American types of organization?  It is
probable that the islands of the Cape de Verd group resemble, in all
their physical conditions, far more closely the Galapagos Islands, than
these latter physically resemble the coast of America, yet the
aboriginal inhabitants of the two groups are totally unlike; those of
the Cape de Verd Islands bearing the impress of Africa, as the
inhabitants of the Galapagos Archipelago are stamped with that of
America.

I have not as yet noticed by far the most remarkable feature in the
natural history of this archipelago; it is, that the different islands
to a considerable extent are inhabited by a different set of beings. My
attention was first called to this fact by the Vice-Governor, Mr.
Lawson, declaring that the tortoises differed from the different
islands, and that he could with certainty tell from which island any
one was brought.  I did not for some time pay sufficient attention to
this statement, and I had already partially mingled together the
collections from two of the islands.  I never dreamed that islands,
about 50 or 60 miles apart, and most of them in sight of each other,
formed of precisely the same rocks, placed under a quite similar
climate, rising to a nearly equal height, would have been differently
tenanted; but we shall soon see that this is the case.  It is the fate
of most voyagers, no sooner to discover what is most interesting in any
locality, than they are hurried from it; but I ought, perhaps, to be
thankful that I obtained sufficient materials to establish this most
remarkable fact in the distribution of organic beings.

The inhabitants, as I have said, state that they can distinguish the
tortoises from the different islands; and that they differ not only in
size, but in other characters.  Captain Porter has described [5] those
from Charles and from the nearest island to it, namely, Hood Island, as
having their shells in front thick and turned up like a Spanish saddle,
whilst the tortoises from James Island are rounder, blacker, and have a
better taste when cooked.  M. Bibron, moreover, informs me that he has
seen what he considers two distinct species of tortoise from the
Galapagos, but he does not know from which islands.  The specimens that
I brought from three islands were young ones: and probably owing to
this cause neither Mr. Gray nor myself could find in them any specific
differences.  I have remarked that the marine Amblyrhynchus was larger
at Albemarle Island than elsewhere; and M. Bibron informs me that he
has seen two distinct aquatic species of this genus; so that the
different islands probably have their representative species or races
of the Amblyrhynchus, as well as of the tortoise.  My attention was
first thoroughly aroused, by comparing together the numerous specimens,
shot by myself and several other parties on board, of the
mocking-thrushes, when, to my astonishment, I discovered that all those
from Charles Island belonged to one species (Mimus trifasciatus) all
from Albemarle Island to M. parvulus; and all from James and Chatham
Islands (between which two other islands are situated, as connecting
links) belonged to M. melanotis.  These two latter species are closely
allied, and would by some ornithologists be considered as only
well-marked races or varieties; but the Mimus trifasciatus is very
distinct. Unfortunately most of the specimens of the finch tribe were
mingled together; but I have strong reasons to suspect that some of the
species of the sub-group Geospiza are confined to separate islands.  If
the different islands have their representatives of Geospiza, it may
help to explain the singularly large number of the species of this
sub-group in this one small archipelago, and as a probable consequence
of their numbers, the perfectly graduated series in the size of their
beaks.  Two species of the sub-group Cactornis, and two of the
Camarhynchus, were procured in the archipelago; and of the numerous
specimens of these two sub-groups shot by four collectors at James
Island, all were found to belong to one species of each; whereas the
numerous specimens shot either on Chatham or Charles Island (for the
two sets were mingled together) all belonged to the two other species:
hence we may feel almost sure that these islands possess their
respective species of these two sub-groups.  In land-shells this law of
distribution does not appear to hold good. In my very small collection
of insects, Mr. Waterhouse remarks, that of those which were ticketed
with their locality, not one was common to any two of the islands.

If we now turn to the Flora, we shall find the aboriginal plants of the
different islands wonderfully different.  I give all the following
results on the high authority of my friend Dr. J. Hooker.  I may
premise that I indiscriminately collected everything in flower on the
different islands, and fortunately kept my collections separate.  Too
much confidence, however, must not be placed in the proportional
results, as the small collections brought home by some other
naturalists though in some respects confirming the results, plainly
show that much remains to be done in the botany of this group: the
Leguminosae, moreover, has as yet been only approximately worked out:--

  ----------------------------------------------------------------
                                                         Number of
                                                         Species
                                                         confined
                                                         to the
                      Number of   Number of              Galapagos
                      species     species      Number    Archipelago
             Total    found in    confined     confined  but found
  Name       Number   other       to the       to the    on more
  of         of       parts of    Galapagos    one       than the
  Island     Species  the world   Archipelago  island    one island
  ----------------------------------------------------------------
  James      71       33          38           30        8
  Albemarle  46       18          26           22        4
  Chatham    32       16          16           12        4
  Charles    68       39          29           21        8
                   (or 29, if
                   the probably
                   imported
                   plants be
                   subtracted.)
  ----------------------------------------------------------------

Hence we have the truly wonderful fact, that in James Island, of the
thirty-eight Galapageian plants, or those found in no other part of the
world, thirty are exclusively confined to this one island; and in
Albemarle Island, of the twenty-six aboriginal Galapageian plants,
twenty-two are confined to this one island, that is, only four are at
present known to grow in the other islands of the archipelago; and so
on, as shown in the above table, with the plants from Chatham and
Charles Islands.  This fact will, perhaps, be rendered even more
striking, by giving a few illustrations:--thus, Scalesia, a remarkable
arborescent genus of the Compositae, is confined to the archipelago: it
has six species: one from Chatham, one from Albemarle, one from Charles
Island, two from James Island, and the sixth from one of the three
latter islands, but it is not known from which: not one of these six
species grows on any two islands.  Again, Euphorbia, a mundane or
widely distributed genus, has here eight species, of which seven are
confined to the archipelago, and not one found on any two islands:
Acalypha and Borreria, both mundane genera, have respectively six and
seven species, none of which have the same species on two islands, with
the exception of one Borreria, which does occur on two islands. The
species of the Compositae are particularly local; and Dr. Hooker has
furnished me with several other most striking illustrations of the
difference of the species on the different islands.  He remarks that
this law of distribution holds good both with those genera confined to
the archipelago, and those distributed in other quarters of the world:
in like manner we have seen that the different islands have their
proper species of the mundane genus of tortoise, and of the widely
distributed American genus of the mocking-thrush, as well as of two of
the Galapageian sub-groups of finches, and almost certainly of the
Galapageian genus Amblyrhynchus.

The distribution of the tenants of this archipelago would not be nearly
so wonderful, if, for instance, one island had a mocking-thrush, and a
second island some other quite distinct genus,--if one island had its
genus of lizard, and a second island another distinct genus, or none
whatever;--or if the different islands were inhabited, not by
representative species of the same genera of plants, but by totally
different genera, as does to a certain extent hold good: for, to give
one instance, a large berry-bearing tree at James Island has no
representative species in Charles Island.  But it is the circumstance,
that several of the islands possess their own species of the tortoise,
mocking-thrush, finches, and numerous plants, these species having the
same general habits, occupying analogous situations, and obviously
filling the same place in the natural economy of this archipelago, that
strikes me with wonder.  It may be suspected that some of these
representative species, at least in the case of the tortoise and of
some of the birds, may hereafter prove to be only well-marked races;
but this would be of equally great interest to the philosophical
naturalist.  I have said that most of the islands are in sight of each
other: I may specify that Charles Island is fifty miles from the
nearest part of Chatham Island, and thirty-three miles from the nearest
part of Albemarle Island.  Chatham Island is sixty miles from the
nearest part of James Island, but there are two intermediate islands
between them which were not visited by me.  James Island is only ten
miles from the nearest part of Albemarle Island, but the two points
where the collections were made are thirty-two miles apart.  I must
repeat, that neither the nature of the soil, nor height of the land,
nor the climate, nor the general character of the associated beings,
and therefore their action one on another, can differ much in the
different islands.  If there be any sensible difference in their
climates, it must be between the Windward group (namely, Charles and
Chatham Islands), and that to leeward; but there seems to be no
corresponding difference in the productions of these two halves of the
archipelago.

The only light which I can throw on this remarkable difference in the
inhabitants of the different islands, is, that very strong currents of
the sea running in a westerly and W.N.W. direction must separate, as
far as transportal by the sea is concerned, the southern islands from
the northern ones; and between these northern islands a strong N.W.
current was observed, which must effectually separate James and
Albemarle Islands.  As the archipelago is free to a most remarkable
degree from gales of wind, neither the birds, insects, nor lighter
seeds, would be blown from island to island.  And lastly, the profound
depth of the ocean between the islands, and their apparently recent (in
a geological sense) volcanic origin, render it highly unlikely that
they were ever united; and this, probably, is a far more important
consideration than any other, with respect to the geographical
distribution of their inhabitants.  Reviewing the facts here given, one
is astonished at the amount of creative force, if such an expression
may be used, displayed on these small, barren, and rocky islands; and
still more so, at its diverse yet analogous action on points so near
each other.  I have said that the Galapagos Archipelago might be called
a satellite attached to America, but it should rather be called a group
of satellites, physically similar, organically distinct, yet intimately
related to each other, and all related in a marked, though much lesser
degree, to the great American continent.

I will conclude my description of the natural history of these islands,
by giving an account of the extreme tameness of the birds.

This disposition is common to all the terrestrial species; namely, to
the mocking-thrushes, the finches, wrens, tyrant-flycatchers, the dove,
and carrion-buzzard.  All of them are often approached sufficiently
near to be killed with a switch, and sometimes, as I myself tried, with
a cap or hat.  A gun is here almost superfluous; for with the muzzle I
pushed a hawk off the branch of a tree.  One day, whilst lying down, a
mocking-thrush alighted on the edge of a pitcher, made of the shell of
a tortoise, which I held in my hand, and began very quietly to sip the
water; it allowed me to lift it from the ground whilst seated on the
vessel: I often tried, and very nearly succeeded, in catching these
birds by their legs. Formerly the birds appear to have been even tamer
than at present.  Cowley (in the year 1684) says that the "Turtledoves
were so tame, that they would often alight on our hats and arms, so as
that we could take them alive, they not fearing man, until such time as
some of our company did fire at them, whereby they were rendered more
shy." Dampier also, in the same year, says that a man in a morning's
walk might kill six or seven dozen of these doves.  At present,
although certainly very tame, they do not alight on people's arms, nor
do they suffer themselves to be killed in such large numbers.  It is
surprising that they have not become wilder; for these islands during
the last hundred and fifty  years have been frequently visited by
bucaniers and whalers; and the sailors, wandering through the wood in
search of tortoises, always take cruel delight in knocking down the
little birds. These birds, although now still more persecuted, do not
readily become wild.  In Charles Island, which had then been colonized
about six years, I saw a boy sitting by a well with a switch in his
hand, with which he killed the doves and finches as they came to drink.
He had already procured a little heap of them for his dinner, and he
said that he had constantly been in the habit of waiting by this well
for the same purpose.  It would appear that the birds of this
archipelago, not having as yet learnt that man is a more dangerous
animal than the tortoise or the Amblyrhynchus, disregard him, in the
same manner as in England shy birds, such as magpies, disregard the
cows and horses grazing in our fields.

The Falkland Islands offer a second instance of birds with a similar
disposition.  The extraordinary tameness of the little Opetiorhynchus
has been remarked by Pernety, Lesson, and other voyagers.  It is not,
however, peculiar to that bird: the Polyborus, snipe, upland and
lowland goose, thrush, bunting, and even some true hawks, are all more
or less tame.  As the birds are so tame there, where foxes, hawks, and
owls occur, we may infer that the absence of all rapacious animals at
the Galapagos, is not the cause of their tameness here.  The upland
geese at the Falklands show, by the precaution they take in building on
the islets, that they are aware of their danger from the foxes; but
they are not by this rendered wild towards man.  This tameness of the
birds, especially of the water-fowl, is strongly contrasted with the
habits of the same species in Tierra del Fuego, where for ages past
they have been persecuted by the wild inhabitants. In the Falklands,
the sportsman may sometimes kill more of the upland geese in one day
than he can carry home; whereas in Tierra del Fuego it is nearly as
difficult to kill one, as it is in England to shoot the common wild
goose.

In the time of Pernety (1763), all the birds there appear to have been
much tamer than at present; he states that the Opetiorhynchus would
almost perch on his finger; and that with a wand he killed ten in half
an hour.  At that period the birds must have been about as tame as they
now are at the Galapagos.  They appear to have learnt caution more
slowly at these latter islands than at the Falklands, where they have
had proportionate means of experience; for besides frequent visits from
vessels, those islands have been at intervals colonized during the
entire period.  Even formerly, when all the birds were so tame, it was
impossible by Pernety's account to kill the black-necked swan--a bird
of passage, which probably brought with it the wisdom learnt in foreign
countries.

I may add that, according to Du Bois, all the birds at Bourbon in
1571-72, with the exception of the flamingoes and geese, were so
extremely tame, that they could be caught by the hand, or killed in any
number with a stick.  Again, at Tristan d'Acunha in the Atlantic,
Carmichael [6] states that the only two land-birds, a thrush and a
bunting, were "so tame as to suffer themselves to be caught with a
hand-net." From these several facts we may, I think, conclude, first,
that the wildness of birds with regard to man, is a particular instinct
directed against _him_, and not dependent upon any general degree of
caution arising from other sources of danger; secondly, that it is not
acquired by individual birds in a short time, even when much
persecuted; but that in the course of successive generations it becomes
hereditary.  With domesticated animals we are accustomed to see new
mental habits or instincts acquired or rendered hereditary; but with
animals in a state of nature, it must always be most difficult to
discover instances of acquired hereditary knowledge.  In regard to the
wildness of birds towards man, there is no way of accounting for it,
except as an inherited habit: comparatively few young birds, in any one
year, have been injured by man in England, yet almost all, even
nestlings, are afraid of him; many individuals, on the other hand, both
at the Galapagos and at the Falklands, have been pursued and injured by
man, yet have not learned a salutary dread of him.  We may infer from
these facts, what havoc the introduction of any new beast of prey must
cause in a country, before the instincts of the indigenous inhabitants
have become adapted to the stranger's craft or power.

[1] The progress of research has shown that some of these birds, which
were then thought to be confined to the islands, occur on the American
continent.  The eminent ornithologist, Mr. Sclater, informs me that
this is the case with the Strix punctatissima and Pyrocephalus nanus;
and probably with the Otus Galapagoensis and Zenaida Galapagoensis: so
that the number of endemic birds is reduced to twenty-three, or
probably to twenty-one.  Mr. Sclater thinks that one or two of these
endemic forms should be ranked rather as varieties than species, which
always seemed to me probable.

[2] This is stated by Dr. Gunther (Zoolog. Soc. Jan 24th, 1859) to be a
peculiar species, not known to inhabit any other country.

[3] Voyage aux Quatre Iles d'Afrique.  With respect to the Sandwich
Islands, see Tyerman and Bennett's Journal, vol. i. p. 434.  For
Mauritius, see Voyage par un Officier, etc., part i. p. 170.  There are
no frogs in the Canary Islands (Webb et Berthelot, Hist. Nat. des Iles
Canaries).  I saw none at St. Jago in the Cape de Verds.  There are
none at St. Helena.

[4] Ann. and Mag. of Nat. Hist., vol. xvi. p. 19.

[5] Voyage in the U. S. ship Essex, vol. i. p. 215.

[6] Linn. Trans., vol. xii. p. 496.  The most anomalous fact on this
subject which I have met with is the wildness of the small birds in the
Arctic parts of North America (as described by Richardson, Fauna Bor.,
vol. ii. p. 332), where they are said never to be persecuted.  This
case is the more strange, because it is asserted that some of the same
species in their winter-quarters in the United States are tame.  There
is much, as Dr. Richardson well remarks, utterly inexplicable connected
with the different degrees of shyness and care with which birds conceal
their nests.  How strange it is that the English wood-pigeon, generally
so wild a bird, should very frequently rear its young in shrubberies
close to houses!



CHAPTER XVIII

TAHITI AND NEW ZEALAND

Pass through the Low Archipelago--Tahiti--Aspect--Vegetation on the
Mountains--View of Eimeo--Excursion into the Interior--Profound
Ravines--Succession of Waterfalls--Number of wild useful
Plants--Temperance of the Inhabitants--Their moral state--Parliament
convened--New Zealand--Bay of Islands--Hippahs--Excursion to
Waimate--Missionary Establishment--English Weeds now run
wild--Waiomio--Funeral of a New Zealand Woman--Sail for Australia.


OCTOBER 20th.--The survey of the Galapagos Archipelago being concluded,
we steered towards Tahiti and commenced our long passage of 3200 miles.
In the course of a few days we sailed out of the gloomy and clouded
ocean-district which extends during the winter far from the coast of
South America.  We then enjoyed bright and clear weather, while running
pleasantly along at the rate of 150 or 160 miles a day before the
steady trade-wind. The temperature in this more central part of the
Pacific is higher than near the American shore.  The thermometer in the
poop cabin, by night and day, ranged between 80 and 83 degs., which
feels very pleasant; but with one degree or two higher, the heat
becomes oppressive.  We passed through the Low or Dangerous
Archipelago, and saw several of those most curious rings of coral land,
just rising above the water's edge, which have been called Lagoon
Islands.  A long and brilliantly white beach is capped by a margin of
green vegetation; and the strip, looking either way, rapidly narrows
away in the distance, and sinks beneath the horizon From the mast-head
a wide expanse of smooth water can be seen within the ring.  These low
hollow coral islands bear no proportion to the vast ocean out of which
they abruptly rise; and it seems wonderful, that such weak invaders are
not overwhelmed, by the all-powerful and never-tiring waves of that
great sea, miscalled the Pacific.

November 15th.--At daylight, Tahiti, an island which must for ever
remain classical to the voyager in the South Sea, was in view.  At a
distance the appearance was not attractive.  The luxuriant vegetation
of the lower part could not yet be seen, and as the clouds rolled past,
the wildest and most precipitous peaks showed themselves towards the
centre of the island.  As soon as we anchored in Matavai Bay, we were
surrounded by canoes.  This was our Sunday, but the Monday of Tahiti:
if the case had been reversed, we should not have received a single
visit; for the injunction not to launch a canoe on the sabbath is
rigidly obeyed. After dinner we landed to enjoy all the delights
produced by the first impressions of a new country, and that country
the charming Tahiti.  A crowd of men, women, and children, was
collected on the memorable Point Venus, ready to receive us with
laughing, merry faces.  They marshalled us towards the house of Mr.
Wilson, the missionary of the district, who met us on the road, and
gave us a very friendly reception.  After sitting a very short time in
his house, we separated to walk about, but returned there in the
evening.

The land capable of cultivation, is scarcely in any part more than a
fringe of low alluvial soil, accumulated round the base of the
mountains, and protected from the waves of the sea by a coral reef,
which encircles the entire line of coast.  Within the reef there is an
expanse of smooth water, like that of a lake, where the canoes of the
natives can ply with safety and where ships anchor.  The low land which
comes down to the beach of coral-sand, is covered by the most beautiful
productions of the intertropical regions.  In the midst of bananas,
orange, cocoa-nut, and bread-fruit trees, spots are cleared where yams,
sweet potatoes, and sugar-cane, and pine-apples are cultivated.  Even
the brushwood is an imported fruit-tree, namely, the guava, which from
its abundance has become as noxious as a weed.  In Brazil I have often
admired the varied beauty of the bananas, palms, and orange-trees
contrasted together; and here we also have the bread-fruit, conspicuous
from its large, glossy, and deeply digitated leaf.  It is admirable to
behold groves of a tree, sending forth its branches with the vigour of
an English oak, loaded with large and most nutritious fruit.  However
seldom the usefulness of an object can account for the pleasure of
beholding it, in the case of these beautiful woods, the knowledge of
their high productiveness no doubt enters largely into the feeling of
admiration.  The little winding paths, cool from the surrounding shade,
led to the scattered houses; the owners of which everywhere gave us a
cheerful and most hospitable reception.

I was pleased with nothing so much as with the inhabitants. There is a
mildness in the expression of their countenances which at once banishes
the idea of a savage; and intelligence which shows that they are
advancing in civilization.  The common people, when working, keep the
upper part of their bodies quite naked; and it is then that the
Tahitians are seen to advantage.  They are very tall, broad-shouldered,
athletic, and well-proportioned.  It has been remarked, that it
requires little habit to make a dark skin more pleasing and natural to
the eye of an European than his own colour.  A white man bathing by the
side of a Tahitian, was like a plant bleached by the gardener's art
compared with a fine dark green one growing vigorously in the open
fields.  Most of the men are tattooed, and the ornaments follow the
curvature of the body so gracefully, that they have a very elegant
effect.  One common pattern, varying in its details, is somewhat like
the crown of a palm-tree. It springs from the central line of the back,
and gracefully curls round both sides.  The simile may be a fanciful
one, but I thought the body of a man thus ornamented was like the trunk
of a noble tree embraced by a delicate creeper.

Many of the elder people had their feet covered with small figures, so
placed as to resemble a sock.  This fashion, however, is partly gone
by, and has been succeeded by others. Here, although fashion is far
from immutable, every one must abide by that prevailing in his youth.
An old man has thus his age for ever stamped on his body, and he cannot
assume the airs of a young dandy.  The women are tattooed in the same
manner as the men, and very commonly on their fingers.  One unbecoming
fashion is now almost universal: namely, shaving the hair from the
upper part of the head, in a circular form, so as to leave only an
outer ring.  The missionaries have tried to persuade the people to
change this habit; but it is the fashion, and that is a sufficient
answer at Tahiti, as well as at Paris.  I was much disappointed in the
personal appearance of the women: they are far inferior in every
respect to the men.  The custom of wearing a white or scarlet flower in
the back of the head, or through a small hole in each ear, is pretty. A
crown of woven cocoa-nut leaves is also worn as a shade for the eyes.
The women appear to be in greater want of some becoming costume even
than the men.

Nearly all the natives understand a little English--that is, they know
the names of common things; and by the aid of this, together with
signs, a lame sort of conversation could be carried on.  In returning
in the evening to the boat, we stopped to witness a very pretty scene.
Numbers of children were playing on the beach, and had lighted bonfires
which illumined the placid sea and surrounding trees; others, in
circles, were singing Tahitian verses.  We seated ourselves on the
sand, and joined their party.  The songs were impromptu, and I believe
related to our arrival: one little girl sang a line, which the rest
took up in parts, forming a very pretty chorus.  The whole scene made
us unequivocally aware that we were seated on the shores of an island
in the far-famed South Sea.

17th.--This day is reckoned in the log-book as Tuesday the 17th,
instead of Monday the 16th, owing to our, so far, successful chase of
the sun.  Before breakfast the ship was hemmed in by a flotilla of
canoes; and when the natives were allowed to come on board, I suppose
there could not have been less than two hundred.  It was the opinion of
every one that it would have been difficult to have picked out an equal
number from any other nation, who would have given so little trouble.
Everybody brought something for sale: shells were the main articles of
trade.  The Tahitians now fully understand the value of money, and
prefer it to old clothes or other articles.  The various coins,
however, of English and Spanish denomination puzzle them, and they
never seemed to think the small silver quite secure until changed into
dollars.  Some of the chiefs have accumulated considerable sums of
money.  One chief, not long since, offered 800 dollars (about 160
pounds sterling) for a small vessel; and frequently they purchase
whale-boats and horses at the rate of from 50 to 100 dollars.

After breakfast I went on shore, and ascended the nearest slope to a
height of between two and three thousand feet. The outer mountains are
smooth and conical, but steep; and the old volcanic rocks, of which
they are formed, have been cut through by many profound ravines,
diverging from the central broken parts of the island to the coast.
Having crossed the narrow low girt of inhabited and fertile land, I
followed a smooth steep ridge between two of the deep ravines.  The
vegetation was singular, consisting almost exclusively of small dwarf
ferns, mingled higher up, with coarse grass; it was not very dissimilar
from that on some of the Welsh hills, and this so close above the
orchard of tropical plants on the coast was very surprising.  At the
highest point, which I reached, trees again appeared.  Of the three
zones of comparative luxuriance, the lower one owes its moisture, and
therefore fertility, to its flatness; for, being scarcely raised above
the level of the sea, the water from the higher land drains away
slowly.  The intermediate zone does not, like the upper one, reach into
a damp and cloudy atmosphere, and therefore remains sterile.  The woods
in the upper zone are very pretty, tree-ferns replacing the cocoa-nuts
on the coast.  It must not, however, be supposed that these woods at
all equal in splendour the forests of Brazil.  The vast numbers of
productions, which characterize a continent, cannot be expected to
occur in an island.

From the highest point which I attained, there was a good view of the
distant island of Eimeo, dependent on the same sovereign with Tahiti.
On the lofty and broken pinnacles, white massive clouds were piled up,
which formed an island in the blue sky, as Eimeo itself did in the blue
ocean.  The island, with the exception of one small gateway, is
completely encircled by a reef.  At this distance, a narrow but
well-defined brilliantly white line was alone visible, where the waves
first encountered the wall of coral.  The mountains rose abruptly out
of the glassy expanse of the lagoon, included within this narrow white
line, outside which the heaving waters of the ocean were dark-coloured.
The view was striking: it may aptly be compared to a framed engraving,
where the frame represents the breakers, the marginal paper the smooth
lagoon, and the drawing the island itself.  When in the evening I
descended from the mountain, a man, whom I had pleased with a trifling
gift, met me, bringing with him hot roasted bananas, a pine-apple, and
cocoa-nuts.  After walking under a burning sun, I do not know anything
more delicious than the milk of a young cocoa-nut.  Pine-apples are
here so abundant that the people eat them in the same wasteful manner
as we might turnips.  They are of an excellent flavor--perhaps even
better than those cultivated in England; and this I believe is the
highest compliment which can be paid to any fruit.  Before going on
board, Mr. Wilson interpreted for me to the Tahitian who had paid me so
adroit an attention, that I wanted him and another man to accompany me
on a short excursion into the mountains.

18th.--In the morning I came on shore early, bringing with me some
provisions in a bag, and two blankets for myself and servant.  These
were lashed to each end of a long pole, which was alternately carried
by my Tahitian companions on their shoulders.  These men are accustomed
thus to carry, for a whole day, as much as fifty pounds at each end of
their poles.  I told my guides to provide themselves with food and
clothing; but they said that there was plenty of food in the mountains,
and for clothing, that their skins were sufficient.  Our line of march
was the valley of Tiaauru, down which a river flows into the sea by
Point Venus. This is one of the principal streams in the island, and
its source lies at the base of the loftiest central pinnacles, which
rise to a height of about 7000 feet.  The whole island is so
mountainous that the only way to penetrate into the interior is to
follow up the valleys.  Our road, at first, lay through woods which
bordered each side of the river; and the glimpses of the lofty central
peaks, seen as through an avenue, with here and there a waving
cocoa-nut tree on one side, were extremely picturesque.  The valley
soon began to narrow, and the sides to grow lofty and more precipitous.
After having walked between three and four hours, we found the width of
the ravine scarcely exceeded that of the bed of the stream.  On each
hand the walls were nearly vertical, yet from the soft nature of the
volcanic strata, trees and a rank vegetation sprung from every
projecting ledge. These precipices must have been some thousand feet
high; and the whole formed a mountain gorge far more magnificent than
anything which I had ever before beheld.  Until the midday sun stood
vertically over the ravine, the air felt cool and damp, but now it
became very sultry.  Shaded by a ledge of rock, beneath a facade of
columnar lava, we ate our dinner.  My guides had already procured a
dish of small fish and fresh-water prawns.  They carried with them a
small net stretched on a hoop; and where the water was deep and in
eddies, they dived, and like otters, with their eyes open followed the
fish into holes and corners, and thus caught them.

The Tahitians have the dexterity of amphibious animals in the water. An
anecdote mentioned by Ellis shows how much they feel at home in this
element.  When a horse was landing for Pomarre in 1817, the slings
broke, and it fell into the water; immediately the natives jumped
overboard, and by their cries and vain efforts at assistance almost
drowned it.  As soon, however, as it reached the shore, the whole
population took to flight, and tried to hide themselves from the
man-carrying pig, as they christened the horse.

A little higher up, the river divided itself into three little streams.
The two northern ones were impracticable, owing to a succession of
waterfalls which descended from the jagged summit of the highest
mountain; the other to all appearance was equally inaccessible, but we
managed to ascend it by a most extraordinary road.  The sides of the
valley were here nearly precipitous, but, as frequently happens with
stratified rocks, small ledges projected, which were thickly covered by
wild bananas, lilaceous plants, and other luxuriant productions of the
tropics.  The Tahitians, by climbing amongst these ledges, searching
for fruit, had discovered a track by which the whole precipice could be
scaled. The first ascent from the valley was very dangerous; for it was
necessary to pass a steeply inclined face of naked rock, by  the aid of
ropes which we brought with us.  How any person discovered that this
formidable spot was the only point where the side of the mountain was
practicable, I cannot imagine.  We then cautiously walked along one of
the ledges till we came to one of the three streams.  This ledge formed
a flat spot, above which a beautiful cascade, some hundred feet in
height, poured down its waters, and beneath, another high cascade fell
into the main stream in the valley below.  From this cool and shady
recess we made a circuit to avoid the overhanging waterfall.  As
before, we followed little projecting ledges, the danger being partly
concealed by the thickness of the vegetation.  In passing from one of
the ledges to another, there was a vertical wall of rock.  One of the
Tahitians, a fine active man, placed the trunk of a tree against this,
climbed up it, and then by the aid of crevices reached the summit.  He
fixed the ropes to a projecting point, and lowered them for our dog and
luggage, and then we clambered up ourselves.  Beneath the ledge on
which the dead tree was placed, the precipice must have been five or
six hundred feet deep; and if the abyss had not been partly concealed
by the overhanging ferns and lilies my head would have turned giddy,
and nothing should have induced me to have attempted it.  We continued
to ascend, sometimes along ledges, and sometimes along knife-edged
ridges, having on each hand profound ravines.  In the Cordillera I have
seen mountains on a far grander scale, but for abruptness, nothing at
all comparable with this. In the evening we reached a flat little spot
on the banks of the same stream, which we had continued to follow, and
which descends in a chain of waterfalls: here we bivouacked for the
night.  On each side of the ravine there were great beds of the
mountain-banana, covered with ripe fruit.  Many of these plants were
from twenty to twenty-five feet high, and from three to four in
circumference.  By the aid of strips of bark for rope, the stems of
bamboos for rafters, and the large leaf of the banana for a thatch, the
Tahitians in a few minutes built us an excellent house; and with
withered leaves made a soft bed.

They then proceeded to make a fire, and cook our evening meal.  A light
was procured, by rubbing a blunt pointed stick in a groove made in
another, as if with intention of deepening it, until by the friction
the dust became ignited. A peculiarly white and very light wood (the
Hibiscus tiliareus) is alone used for this purpose: it is the same
which serves for poles to carry any burden, and for the floating
out-riggers to their canoes.  The fire was produced in a few seconds:
but to a person who does not understand the art, it requires, as I
found, the greatest exertion; but at last, to my great pride, I
succeeded in igniting the dust.  The Gaucho in the Pampas uses a
different method: taking an elastic stick about eighteen inches long,
he presses one end on his breast, and the other pointed end into a hole
in a piece of wood, and then rapidly turns the curved part, like a
carpenter's centre-bit.  The Tahitians having made a small fire of
sticks, placed a score of stones, of about the size of cricket-balls,
on the burning wood.  In about ten minutes the sticks were consumed,
and the stones hot.  They had previously folded up in small parcels of
leaves, pieces of beef, fish, ripe and unripe bananas, and the tops of
the wild arum. These green parcels were laid in a layer between two
layers of the hot stones, and the whole then covered up with earth, so
that no smoke or steam could escape.  In about a quarter of an hour,
the whole was most deliciously cooked. The choice green parcels were
now laid on a cloth of banana leaves, and with a cocoa-nut shell we
drank the cool water of the running stream; and thus we enjoyed our
rustic meal.

I could not look on the surrounding plants without admiration. On every
side were forests of banana; the fruit of which, though serving for
food in various ways, lay in heaps decaying on the ground.  In front of
us there was an extensive brake of wild sugar-cane; and the stream was
shaded by the dark green knotted stem of the Ava,--so famous in former
days for its powerful intoxicating effects.  I chewed a piece, and
found that it had an acrid and unpleasant taste, which would have
induced any one at once to have pronounced it poisonous.  Thanks to the
missionaries, this plant now thrives only in these deep ravines,
innocuous to every one.  Close by I saw the wild arum, the roots of
which, when well baked, are good to eat, and the young leaves better
than spinach.  There was the wild yam, and a liliaceous plant called
Ti, which grows in abundance, and has a soft brown root, in shape and
size like a huge log of wood: this served us for dessert, for it is as
sweet as treacle, and  with a pleasant taste.  There were, moreover,
several other wild fruits, and useful vegetables.  The little stream,
besides its cool water, produced eels, and cray-fish.  I did indeed
admire this scene, when I compared it with an uncultivated one in the
temperate zones.  I felt the force of the remark, that man, at least
savage man, with his reasoning powers only partly developed, is the
child of the tropics.

As the evening drew to a close, I strolled beneath the gloomy shade of
the bananas up the course of the stream. My walk was soon brought to a
close, by coming to a waterfall between two and three hundred feet
high; and again above this there was another.  I mention all these
waterfalls in this one brook, to give a general idea of the inclination
of the land.  In the little recess where the water fell, it did not
appear that a breath of wind had ever blown.  The thin edges of the
great leaves of the banana, damp with spray, were unbroken, instead of
being, as is so generally the case, split into a thousand shreds.  From
our position, almost suspended on the mountain side, there were
glimpses into the depths of the neighbouring valleys; and the lofty
points of the central mountains, towering up within sixty degrees of
the zenith, hid half the evening sky.  Thus seated, it was a sublime
spectacle to watch the shades of night gradually obscuring the last and
highest pinnacles.

Before we laid ourselves down to sleep, the elder Tahitian fell on his
knees, and with closed eyes repeated a long prayer in his native
tongue.  He prayed as a Christian should do, with fitting reverence,
and without the fear of ridicule or any ostentation of piety.  At our
meals neither of the men would taste food, without saying beforehand a
short grace. Those travellers who think that a Tahitian prays only when
the eyes of the missionary are fixed on him, should have slept with us
that night on the mountain-side.  Before morning it rained very
heavily; but the good thatch of banana-leaves kept us dry.

November 19th.--At daylight my friends, after their morning prayer,
prepared an excellent breakfast in the same manner as in the evening.
They themselves certainly partook of it largely; indeed I never saw any
men eat near so much.  I suppose such enormously capacious stomachs
must be the effect of a large part of their diet consisting of fruit
and vegetables, which contain, in a given bulk, a comparatively small
portion of nutriment.  Unwittingly, I was the means of my companions
breaking, as I afterwards learned, one of their own laws, and
resolutions: I took with me a flask of spirits, which they could not
refuse to partake of; but as often as they drank a little, they put
their fingers before their mouths, and uttered the word "Missionary."
About two years ago, although the use of the ava was prevented,
drunkenness from the introduction of spirits became very prevalent. The
missionaries prevailed on a few good men, who saw that their country
was rapidly going to ruin, to join with them in a Temperance Society.
From good sense or shame, all the chiefs and the queen were at last
persuaded to join.  Immediately a law was passed, that no spirits
should be allowed to be introduced into the island, and that he who
sold and he who bought the forbidden article should be punished by a
fine.  With remarkable justice, a certain period was allowed for stock
in hand to be sold, before the law came into effect.  But when it did,
a general search was made, in which even the houses of the missionaries
were not exempted, and all the ava (as the natives call all ardent
spirits) was poured on the ground. When one reflects on the effect of
intemperance on the aborigines of the two Americas, I think it will be
acknowledged that every well-wisher of Tahiti owes no common debt of
gratitude to the missionaries.  As long as the little island of St.
Helena remained under the government of the East India Company,
spirits, owing to the great injury they had produced, were not allowed
to be imported; but wine was supplied from the Cape of Good Hope.  It
is rather a striking and not very gratifying fact, that in the same
year that spirits were allowed to be sold in Helena, their use was
banished from Tahiti by the free will of the people.

After breakfast we proceeded on our Journey.  As my object was merely
to see a little of the interior scenery, we returned by another track,
which descended into the main valley lower down.  For some distance we
wound, by a most intricate path, along the side of the mountain which
formed the valley.  In the less precipitous parts we passed through
extensive groves of the wild banana.  The Tahitians, with their naked,
tattooed bodies, their heads ornamented with flowers, and seen in the
dark shade of these groves, would have formed a fine picture of man
inhabiting some primeval land.  In our descent we followed the line of
ridges; these were exceedingly narrow, and for considerable lengths
steep as a ladder; but all clothed with vegetation.  The extreme care
necessary in poising each step rendered the walk fatiguing. I did not
cease to wonder at these ravines and precipices: when viewing the
country from one of the knife-edged ridges, the point of support was so
small, that the effect was nearly the same as it must be from a
balloon.  In this descent we had occasion to use the ropes only once,
at the point where we entered the main valley.  We slept under the same
ledge of rock where we had dined the day before: the night was fine,
but from the depth and narrowness of the gorge, profoundly dark.

Before actually seeing this country, I found it difficult to understand
two facts mentioned by Ellis; namely, that after the murderous battles
of former times, the survivors on the conquered side retired into the
mountains, where a handful of men could resist a multitude.  Certainly
half a dozen men, at the spot where the Tahitian reared the old tree,
could easily have repulsed thousands.  Secondly, that after the
introduction of Christianity, there were wild men who lived in the
mountains, and whose retreats were unknown to the more civilized
inhabitants.

November 20th.--In the morning we started early, and reached Matavai at
noon.  On the road we met a large party of noble athletic men, going
for wild bananas.  I found that the ship, on account of the difficulty
in watering, had moved to the harbour of Papawa, to which place I
immediately walked.  This is a very pretty spot.  The cove is
surrounded by reefs, and the water as smooth as in a lake.  The
cultivated ground, with its beautiful productions, interspersed with
cottages, comes close down to the water's edge. From the varying
accounts which I had read before reaching these islands, I was very
anxious to form, from my own observation, a judgment of their moral
state,--although such judgment would necessarily be very imperfect.
First impressions at all times very much depend on one's previously
acquired ideas.  My notions were drawn from Ellis's "Polynesian
Researches"--an admirable and most interesting work, but naturally
looking at everything under a favourable point of view, from Beechey's
Voyage; and from that of Kotzebue, which is strongly adverse to the
whole missionary system.  He who compares these three accounts will, I
think, form a tolerably accurate conception of the present state of
Tahiti.  One of my impressions which I took from the two last
authorities, was decidedly incorrect; viz., that the Tahitians had
become a gloomy race, and lived in fear of the missionaries.  Of the
latter feeling I saw no trace, unless, indeed, fear and respect be
confounded under one name. Instead of discontent being a common
feeling, it would be difficult in Europe to pick out of a crowd half so
many merry and happy faces.  The prohibition of the flute and dancing
is inveighed against as wrong and foolish;--the more than presbyterian
manner of keeping the sabbath is looked at in a similar light.  On
these points I will not pretend to offer any opinion to men who have
resided as many years as I was days on the island.

On the whole, it appears to me that the morality and religion of the
inhabitants are highly creditable.  There are many who attack, even
more acrimoniously than Kotzebue, both the missionaries, their system,
and the effects produced by it.  Such reasoners never compare the
present state with that of the island only twenty years ago; nor even
with that of Europe at this day; but they compare it with the high
standard of Gospel perfection.  They expect the missionaries to effect
that which the Apostles themselves failed to do. Inasmuch as the
condition of the people falls short of this high standard, blame is
attached to the missionary, instead of credit for that which he has
effected.  They forget, or will not remember, that human sacrifices,
and the power of an idolatrous priesthood--a system of profligacy
unparalleled in any other part of the world--infanticide a consequence
of that system--bloody wars, where the conquerors spared neither women
nor children--that all these have been abolished; and that dishonesty,
intemperance, and licentiousness have been greatly reduced by the
introduction of Christianity. In a voyager to forget these things is
base ingratitude; for should he chance to be at the point of shipwreck
on some unknown coast, he will most devoutly pray that the lesson of
the missionary may have extended thus far.

In point of morality, the virtue of the women, it has been often said,
is most open to exception.  But before they are blamed too severely, it
will be well distinctly to call to mind the scenes described by Captain
Cook and Mr. Banks, in which the grandmothers and mothers of the
present race played a part.  Those who are most severe, should consider
how much of the morality of the women in Europe is owing to the system
early impressed by mothers on their daughters, and how much in each
individual case to the precepts of religion.  But it is useless to
argue against such reasoners;--I believe that, disappointed in not
finding the field of licentiousness quite so open as formerly, they
will not give credit to a morality which they do not wish to practise,
or to a religion which they undervalue, if not despise.

Sunday, 22nd.--The harbour of Papiete, where the queen resides, may be
considered as the capital of the island: it is also the seat of
government, and the chief resort of shipping. Captain Fitz Roy took a
party there this day to hear divine service, first in the Tahitian
language, and afterwards in our own.  Mr. Pritchard, the leading
missionary in the island, performed the service.  The chapel consisted
of a large airy framework of wood; and it was filled to excess by tidy,
clean people, of all ages and both sexes.  I was rather disappointed in
the apparent degree of attention; but I believe my expectations were
raised too high.  At all events the appearance was quite equal to that
in a country church in England. The singing of the hymns was decidedly
very pleasing, but the language from the pulpit, although fluently
delivered, did not sound well: a constant repetition of words, like
"tata ta, mata mai," rendered it monotonous.  After English service, a
party returned on foot to Matavai.  It was a pleasant walk, sometimes
along the sea-beach and sometimes under the shade of the many beautiful
trees.

About two years ago, a small vessel under English colours was plundered
by some of the inhabitants of the Low Islands, which were then under
the dominion of the Queen of Tahiti. It was believed that the
perpetrators were instigated to this act by some indiscreet laws issued
by her majesty.  The British government demanded compensation; which
was acceded to, and the sum of nearly three thousand dollars was agreed
to be paid on the first of last September.  The Commodore at Lima
ordered Captain Fitz Roy to inquire concerning this debt, and to demand
satisfaction if it were not paid.  Captain Fitz Roy accordingly
requested an interview with the Queen Pomarre, since famous from the
ill-treatment she had received from the French; and a parliament was
held to consider the question, at which all the principal chiefs of the
island and the queen were assembled.  I will not attempt to describe
what took place, after the interesting account given by Captain Fitz
Roy.  The money, it appeared, had not been paid; perhaps the alleged
reasons were rather equivocal; but otherwise I cannot sufficiently
express our general surprise at the extreme good sense, the reasoning
powers, moderation, candour, and prompt resolution, which were
displayed on all sides.  I believe we all left the meeting with a very
different opinion of the Tahitians, from what we entertained when we
entered.  The chiefs and people resolved to subscribe and complete the
sum which was wanting; Captain Fitz Roy urged that it was hard that
their private property should be sacrificed for the crimes of distant
islanders.  They replied, that they were grateful for his
consideration, but that Pomarre was their Queen, and that they were
determined to help her in this her difficulty.  This resolution and its
prompt execution, for a book was opened early the next morning, made a
perfect conclusion to this very remarkable scene of loyalty and good
feeling.

After the main discussion was ended, several of the chiefs took the
opportunity of asking Captain Fitz Roy many intelligent questions on
international customs and laws, relating to the treatment of ships and
foreigners.  On some points, as soon as the decision was made, the law
was issued verbally on the spot.  This Tahitian parliament lasted for
several hours; and when it was over Captain Fitz Roy invited Queen
Pomarre to pay the Beagle a visit.

November 25th.--In the evening four boats were sent for her majesty;
the ship was dressed with flags, and the yards manned on her coming on
board.  She was accompanied by most of the chiefs.  The behaviour of
all was very proper: they begged for nothing, and seemed much pleased
with Captain Fitz Roy's presents.  The queen is a large awkward woman,
without any beauty, grace or dignity.  She has only one royal
attribute: a perfect immovability of expression under all
circumstances, and that rather a sullen one.  The rockets were most
admired, and a deep "Oh!" could be heard from the shore, all round the
dark bay, after each explosion.  The sailors' songs were also much
admired; and the queen said she thought that one of the most boisterous
ones certainly could not be a hymn!  The royal party did not return on
shore till past midnight.

26th.--In the evening, with a gentle land-breeze, a course was steered
for New Zealand; and as the sun set, we had a farewell view of the
mountains of Tahiti--the island to which every voyager has offered up
his tribute of admiration.

December 19th.--In the evening we saw in the distance New Zealand. We
may now consider that we have nearly crossed the Pacific.  It is
necessary to sail over this great ocean to comprehend its immensity.
Moving quickly onwards for weeks together, we meet with nothing but the
same blue, profoundly deep, ocean.  Even within the archipelagoes, the
islands are mere specks, and far distant one from the other. Accustomed
to look at maps drawn on a small scale, where dots, shading, and names
are crowded together, we do not rightly judge how infinitely small the
proportion of dry land is to water of this vast expanse. The meridian
of the Antipodes has likewise been passed; and now every league, it
made us happy to think, was one league nearer to England. These
Antipodes call to one's mind old recollections of childish doubt and
wonder.  Only the other day I looked forward to this airy barrier as a
definite point in our voyage homewards; but now I find it, and all such
resting-places for the imagination, are like shadows, which a man
moving onwards cannot catch.  A gale of wind lasting for some days, has
lately given us full leisure to measure the future stages in our
homeward voyage, and to wish most earnestly for its termination.

December 21st.--Early in the morning we entered the Bay of Islands, and
being becalmed for some hours near the mouth, we did not reach the
anchorage till the middle of the day.  The country is hilly, with a
smooth outline, and is deeply intersected by numerous arms of the sea
extending from the bay.  The surface appears from a distance as if
clothed with coarse pasture, but this in truth is nothing but fern.  On
the more distant hills, as well as in parts of the valleys, there is a
good deal of woodland.  The general tint of the landscape is not a
bright green; and it resembles the country a short distance to the
south of Concepcion in Chile. In several parts of the bay, little
villages of square tidy looking houses are scattered close down to the
water's edge. Three whaling-ships were lying at anchor, and a canoe
every now and then crossed from shore to shore; with these exceptions,
an air of extreme quietness reigned over the whole district.  Only a
single canoe came alongside.  This, and the aspect of the whole scene,
afforded a remarkable, and not very pleasing contrast, with our joyful
and boisterous welcome at Tahiti.

In the afternoon we went on shore to one of the larger groups of
houses, which yet hardly deserves the title of a village.  Its name is
Pahia: it is the residence of the missionaries; and there are no native
residents except servants and labourers.  In the vicinity of the Bay of
Islands, the number of Englishmen, including their families, amounts to
between two and three hundred.  All the cottages, many of which are
whitewashed and look very neat, are the property of the English.  The
hovels of the natives are so diminutive and paltry, that they can
scarcely be perceived from a distance. At Pahia, it was quite pleasing
to behold the English flowers in the gardens before the houses; there
were roses of several kinds, honeysuckle, jasmine, stocks, and whole
hedges of sweetbrier.

December 22nd.--In the morning I went out walking; but I soon found
that the country was very impracticable.  All the hills are thickly
covered with tall fern, together with a low bush which grows like a
cypress; and very little ground has been cleared or cultivated.  I then
tried the sea-beach; but proceeding towards either hand, my walk was
soon stopped by salt-water creeks and deep brooks.  The communication
between the inhabitants of the different parts of the bay, is (as in
Chiloe) almost entirely kept up by boats.  I was surprised to find that
almost every hill which I ascended, had been at some former time more
or less fortified.  The summits were cut into steps or successive
terraces, and frequently they had been protected by deep trenches.  I
afterwards observed that the principal hills inland in like manner
showed an artificial outline.  These are the Pas, so frequently
mentioned by Captain Cook under the name of "hippah;" the difference of
sound being owing to the prefixed article.

That the Pas had formerly been much used, was evident from the piles of
shells, and the pits in which, as I was informed, sweet potatoes used
to be kept as a reserve.  As there was no water on these hills, the
defenders could never have anticipated a long siege, but only a hurried
attack for plunder, against which the successive terraces would have
afforded good protection.  The general introduction of fire-arms has
changed the whole system of warfare; and an exposed situation on the
top of a hill is now worse than useless. The Pas in consequence are, at
the present day, always built on a level piece of ground.  They consist
of a double stockade of thick and tall posts, placed in a zigzag line,
so that every part can be flanked.  Within the stockade a mound of
earth is thrown up, behind which the defenders can rest in safety, or
use their fire-arms over it.  On the level of the ground little
archways sometimes pass through this breastwork, by which means the
defenders can crawl out to the stockade and reconnoitre their enemies.
The Rev. W. Williams, who gave me this account, added, that in one Pas
he had noticed spurs or buttresses projecting on the inner and
protected side of the mound of earth.  On asking the chief the use of
them, he replied, that if two or three of his men were shot, their
neighbours would not see the bodies, and so be discouraged.

These Pas are considered by the New Zealanders as very perfect means of
defence: for the attacking force is never so well disciplined as to
rush in a body to the stockade, cut it down, and effect their entry.
When a tribe goes to war, the chief cannot order one party to go here
and another there; but every man fights in the manner which best
pleases himself; and to each separate individual to approach a stockade
defended by fire-arms must appear certain death.  I should think a more
warlike race of inhabitants could not be found in any part of the world
than the New Zealanders. Their conduct on first seeing a ship, as
described by Captain Cook, strongly illustrates this: the act of
throwing volleys of stones at so great and novel an object, and their
defiance of "Come on shore and we will kill and eat you all," shows
uncommon boldness.  This warlike spirit is evident in many of their
customs, and even in their smallest actions.  If a New Zealander is
struck, although but in joke, the blow must be returned and of this I
saw an instance with one of our officers.

At the present day, from the progress of civilization, there is much
less warfare, except among some of the southern tribes.  I heard a
characteristic anecdote of what took place some time ago in the south.
A missionary found a chief and his tribe in preparation for war;--their
muskets clean and bright, and their ammunition ready.  He reasoned long
on the inutility of the war, and the little provocation which had been
given for it.  The chief was much shaken in his resolution, and seemed
in doubt: but at length it occurred to him that a barrel of his
gunpowder was in a bad state, and that it would not keep much longer.
This was brought forward as an unanswerable argument for the necessity
of immediately declaring war: the idea of allowing so much good
gunpowder to spoil was not to be thought of; and this settled the
point.  I was told by the missionaries that in the life of Shongi, the
chief who visited England, the love of war was the one and lasting
spring of every action.  The tribe in which he was a principal chief
had at one time been oppressed by another tribe from the Thames River.
A solemn oath was taken by the men that when their boys should grow up,
and they should be powerful enough, they would never forget or forgive
these injuries.  To fulfil this oath appears to have been Shongi's
chief motive for going to England; and when there it was his sole
object.  Presents were valued only as they could be converted into
arms; of the arts, those alone interested him which were connected with
the manufacture of arms.  When at Sydney, Shongi, by a strange
coincidence, met the hostile chief of the Thames River at the house of
Mr. Marsden: their conduct was civil to each other; but Shongi told him
that when again in New Zealand he would never cease to carry war into
his country. The challenge was accepted; and Shongi on his return
fulfilled the threat to the utmost letter.  The tribe on the Thames
River was utterly overthrown, and the chief to whom the challenge had
been given was himself killed. Shongi, although harbouring such deep
feelings of hatred and revenge, is described as having been a
good-natured person.

In the evening I went with Captain Fitz Roy and Mr. Baker, one of the
missionaries, to pay a visit to Kororadika: we wandered about the
village, and saw and conversed with many of the people, both men,
women, and children.  Looking at the New Zealander, one naturally
compares him with the Tahitian; both belonging to the same family of
mankind. The comparison, however, tells heavily against the New
Zealander.  He may, perhaps be superior in energy, but in every other
respect his character is of a much lower order.  One glance at their
respective expressions, brings conviction to the mind that one is a
savage, the other a civilized man.  It would be vain to seek in the
whole of New Zealand a person with the face and mien of the old
Tahitian chief Utamme.  No doubt the extraordinary manner in which
tattooing is here practised, gives a disagreeable expression to their
countenances.  The complicated but symmetrical figures covering the
whole face, puzzle and mislead an unaccustomed eye: it is moreover
probable, that the deep incisions, by destroying the play of the
superficial muscles, give an air of rigid inflexibility.  But, besides
this, there is a twinkling in the eye, which cannot indicate anything
but cunning and ferocity.  Their figures are tall and bulky; but not
comparable in elegance with those of the working-classes in Tahiti.

But their persons and houses are filthily dirty and offensive: the idea
of washing either their bodies or their clothes never seems to enter
their heads.  I saw a chief, who was wearing a shirt black and matted
with filth, and when asked how it came to be so dirty, he replied, with
surprise, "Do not you see it is an old one?" Some of the men have
shirts; but the common dress is one or two large blankets, generally
black with dirt, which are thrown over their shoulders in a very
inconvenient and awkward fashion.  A few of the principal chiefs have
decent suits of English clothes; but these are only worn on great
occasions.

December 23rd.--At a place called Waimate, about fifteen miles from the
Bay of Islands, and midway between the eastern and western coasts, the
missionaries have purchased some land for agricultural purposes.  I had
been introduced to the Rev. W. Williams, who, upon my expressing a
wish, invited me to pay him a visit there.  Mr. Bushby, the British
resident, offered to take me in his boat by a creek, where I should see
a pretty waterfall, and by which means my walk would be shortened.  He
likewise procured for me a guide.

Upon asking a neighbouring chief to recommend a man, the chief himself
offered to go; but his ignorance of the value of money was so complete,
that at first he asked how many pounds I would give him, but afterwards
was well contented with two dollars.  When I showed the chief a very
small bundle, which I wanted carried, it became absolutely necessary
for him to take a slave.  These feelings of pride are beginning to wear
away; but formerly a leading man would sooner have died, than undergone
the indignity of carrying the smallest burden.  My companion was a
light active man, dressed in a dirty blanket, and with his face
completely tattooed.  He had formerly been a great warrior.  He
appeared to be on very cordial terms with Mr. Bushby; but at various
times they had quarrelled violently.  Mr. Bushby remarked that a little
quiet irony would frequently silence any one of these natives in their
most blustering moments. This chief has come and harangued Mr. Bushby
in a hectoring manner, saying, "great chief, a great man, a friend of
mine, has come to pay me a visit--you must give him something good to
eat, some fine presents, etc." Mr. Bushby has allowed him to finish his
discourse, and then has quietly replied by some answer such as, "What
else shall your slave do for you?" The man would then instantly, with a
very comical expression, cease his braggadocio.

Some time ago, Mr. Bushby suffered a far more serious attack.  A chief
and a party of men tried to break into his house in the middle of the
night, and not finding this so easy, commenced a brisk firing with
their muskets.  Mr. Bushby was slightly wounded, but the party was at
length driven away.  Shortly afterwards it was discovered who was the
aggressor; and a general meeting of the chiefs was convened to consider
the case.  It was considered by the New Zealanders as very atrocious,
inasmuch as it was a night attack, and that Mrs. Bushby was lying ill
in the house: this latter circumstance, much to their honour, being
considered in all cases as a protection.  The chiefs agreed to
confiscate the land of the aggressor to the King of England.  The whole
proceeding, however, in thus trying and punishing a chief was entirely
without precedent.  The aggressor, moreover, lost caste in the
estimation of his equals and this was considered by the British as of
more consequence than the confiscation of his land.

As the boat was shoving off, a second chief stepped into her, who only
wanted the amusement of the passage up and down the creek.  I never saw
a more horrid and ferocious expression than this man had.  It
immediately struck me I had somewhere seen his likeness: it will be
found in Retzch's outlines to Schiller's ballad of Fridolin, where two
men are pushing Robert into the burning iron furnace.  It is the man
who has his arm on Robert's breast.  Physiognomy here spoke the truth;
this chief had been a notorious murderer, and was an arrant coward to
boot.  At the point where the boat landed, Mr. Bushby accompanied me a
few hundred yards on the road: I could not help admiring the cool
impudence of the hoary old villain, whom we left lying in the boat,
when he shouted to Mr. Bushby, "Do not you stay long, I shall be tired
of waiting here."

We now commenced our walk.  The road lay along a well beaten path,
bordered on each side by the tall fern, which covers the whole country.
After travelling some miles, we came to a little country village, where
a few hovels were collected together, and some patches of ground
cultivated with potatoes.  The introduction of the potato has been the
most essential benefit to the island; it is now much more used than any
native vegetable.  New Zealand is favoured by one great natural
advantage; namely, that the inhabitants can never perish from famine.
The whole country abounds with fern: and the roots of this plant, if
not very palatable, yet contain much nutriment.  A native can always
subsist on these, and on the shell-fish, which are abundant on all
parts of the sea-coast.  The villages are chiefly conspicuous by the
platforms which are raised on four posts ten or twelve feet above the
ground, and on which the produce of the fields is kept secure from all
accidents.

On coming near one of the huts I was much amused by seeing in due form
the ceremony of rubbing, or, as it ought to be called, pressing noses.
The women, on our first approach, began uttering something in a most
dolorous voice; they then squatted themselves down and held up their
faces; my companion standing over them, one after another, placed the
bridge of his nose at right angles to theirs, and commenced pressing.
This lasted rather longer than a cordial shake of the hand with us, and
as we vary the force of the grasp of the hand in shaking, so do they in
pressing.  During the process they uttered comfortable little grunts,
very much in the same manner as two pigs do, when rubbing against each
other.  I noticed that the slave would press noses with any one he met,
indifferently either before or after his master the chief.  Although
among the savages, the chief has absolute power of life and death over
his slave, yet there is an entire absence of ceremony between them. Mr.
Burchell has remarked the same thing in Southern Africa, with the rude
Bachapins.  Where civilization has arrived at a certain point, complex
formalities soon arise between the different grades of society: thus at
Tahiti all were formerly obliged to uncover themselves as low as the
waist in presence of the king.

The ceremony of pressing noses having been duly completed with all
present, we seated ourselves in a circle in the front of one of the
hovels, and rested there half-an-hour. All the hovels have nearly the
same form and dimensions, and all agree in being filthily dirty.  They
resemble a cow-shed with one end open, but having a partition a little
way within, with a square hole in it, making a small gloomy chamber. In
this the inhabitants keep all their property, and when the weather is
cold they sleep there.  They eat, however, and pass their time in the
open part in front.  My guides having finished their pipes, we
continued our walk. The path led through the same undulating country,
the whole uniformly clothed as before with fern.  On our right hand we
had a serpentine river, the banks of which were fringed with trees, and
here and there on the hill sides there was a clump of wood.  The whole
scene, in spite of its green colour, had rather a desolate aspect.  The
sight of so much fern impresses the mind with an idea of sterility:
this, however, is not correct; for wherever the fern grows thick and
breast-high, the land by tillage becomes productive.  Some of the
residents think that all this extensive open country originally was
covered with forests, and that it has been cleared by fire. It is said,
that by digging in the barest spots, lumps of the kind of resin which
flows from the kauri pine are frequently found.  The natives had an
evident motive in clearing the country; for the fern, formerly a staple
article of food, flourishes only in the open cleared tracks.  The
almost entire absence of associated grasses, which forms so remarkable
a feature in the vegetation of this island, may perhaps be accounted
for by the land having been aboriginally covered with forest-trees.

The soil is volcanic; in several parts we passed over shaggy lavas, and
craters could clearly be distinguished on several of the neighbouring
hills.  Although the scenery is nowhere beautiful, and only
occasionally pretty, I enjoyed my walk.  I should have enjoyed it more,
if my companion, the chief, had not possessed extraordinary
conversational powers.  I knew only three words: "good," "bad," and
"yes:" and with these I answered all his remarks, without of course
having understood one word he said.  This, however, was quite
sufficient: I was a good listener, an agreeable person, and he never
ceased talking to me.

At length we reached Waimate.  After having passed over so many miles
of an uninhabited useless country, the sudden appearance of an English
farm-house, and its well-dressed fields, placed there as if by an
enchanter's wand, was exceedingly pleasant.  Mr. Williams not being at
home, I received in Mr. Davies's house a cordial welcome.  After
drinking tea with his family party, we took a stroll about the farm. At
Waimate there are three large houses, where the missionary gentlemen,
Messrs. Williams, Davies, and Clarke, reside; and near them are the
huts of the native labourers.  On an adjoining slope, fine crops of
barley and wheat were standing in full ear; and in another part, fields
of potatoes and clover. But I cannot attempt to describe all I saw;
there were large gardens, with every fruit and vegetable which England
produces; and many belonging to a warmer clime.  I may instance
asparagus, kidney beans, cucumbers, rhubarb, apples, pears, figs,
peaches, apricots, grapes, olives, gooseberries, currants, hops, gorse
for fences, and English oaks; also many kinds of flowers.  Around the
farm-yard there were stables, a thrashing-barn with its winnowing
machine, a blacksmith's forge, and on the ground ploughshares and other
tools: in the middle was that happy mixture of pigs and poultry, lying
comfortably together, as in every English farm-yard.  At the distance
of a few hundred yards, where the water of a little rill had been
dammed up into a pool, there was a large and substantial water-mill.

All this is very surprising, when it is considered that five years ago
nothing but the fern flourished here.  Moreover, native workmanship,
taught by the missionaries, has effected this change;--the lesson of
the missionary is the enchanter's wand.  The house had been built, the
windows framed, the fields ploughed, and even the trees grafted, by a
New Zealander. At the mill, a New Zealander was seen powdered white
with flower, like his brother miller in England.  When I looked at this
whole scene, I thought it admirable.  It was not merely that England
was brought vividly before my mind; yet, as the evening drew to a
close, the domestic sounds, the fields of corn, the distant undulating
country with its trees might well have been mistaken for our
fatherland: nor was it the triumphant feeling at seeing what Englishmen
could effect; but rather the high hopes thus inspired for the future
progress of this fine island.


Several young men, redeemed by the missionaries from slavery, were
employed on the farm.  They were dressed in a shirt, jacket, and
trousers, and had a respectable appearance. Judging from one trifling
anecdote, I should think they must be honest.  When walking in the
fields, a young labourer came up to Mr. Davies, and gave him a knife
and gimlet, saying that he had found them on the road, and did not know
to whom they belonged!  These young men and boys appeared very merry
and good-humoured.  In the evening I saw a party of them at cricket:
when I thought of the austerity of which the missionaries have been
accused, I was amused by observing one of their own sons taking an
active part in the game.  A more decided and pleasing change was
manifested in the young women, who acted as servants within the houses.
Their clean, tidy, and healthy appearance, like that of the dairy-maids
in England, formed a wonderful contrast with the women of the filthy
hovels in Kororadika. The wives of the missionaries tried to persuade
them not to be tattooed; but a famous operator having arrived from the
south, they said, "We really must just have a few lines on our lips;
else when we grow old, our lips will shrivel, and we shall be so very
ugly." There is not nearly so much tattooing as formerly; but as it is
a badge of distinction between the chief and the slave, it will
probably long be practised.  So soon does any train of ideas become
habitual, that the missionaries told me that even in their eyes a plain
face looked mean, and not like that of a New Zealand gentleman.

Late in the evening I went to Mr. Williams's house, where I passed the
night.  I found there a large party of children, collected together for
Christmas Day, and all sitting round a table at tea.  I never saw a
nicer or more merry group; and to think that this was in the centre of
the land of cannibalism, murder, and all atrocious crimes!  The
cordiality and happiness so plainly pictured in the faces of the little
circle, appeared equally felt by the older persons of the mission.

December 24th.--In the morning, prayers were read in the native tongue
to the whole family.  After breakfast I rambled about the gardens and
farm.  This was a market-day, when the natives of the surrounding
hamlets bring their potatoes, Indian corn, or pigs, to exchange for
blankets, tobacco, and sometimes, through the persuasions of the
missionaries, for soap.  Mr. Davies's eldest son, who manages a farm of
his own, is the man of business in the market.  The children of the
missionaries, who came while young to the island, understand the
language better than their parents, and can get anything more readily
done by the natives.

A little before noon Messrs. Williams and Davies walked with me to a
part of a neighbouring forest, to show me the famous kauri pine.  I
measured one of the noble trees, and found it thirty-one feet in
circumference above the roots. There was another close by, which I did
not see, thirty-three feet; and I heard of one no less than forty feet.
These trees are remarkable for their smooth cylindrical boles, which
run up to a height of sixty, and even ninety feet, with a nearly equal
diameter, and without a single branch.  The crown of branches at the
summit is out of all proportion small to the trunk; and the leaves are
likewise small compared with the branches.  The forest was here almost
composed of the kauri; and the largest trees, from the parallelism of
their sides, stood up like gigantic columns of wood.  The timber of the
kauri is the most valuable production of the island; moreover, a
quantity of resin oozes from the bark, which is sold at a penny a pound
to the Americans, but its use was then unknown.  Some of the New
Zealand forest must be impenetrable to an extraordinary degree.  Mr.
Matthews informed me that one forest only thirty-four miles in width,
and separating two inhabited districts, had only lately, for the first
time, been crossed.  He and another missionary, each with a party of
about fifty men, undertook to open a road, but it cost more than a
fortnight's labour!  In the woods I saw very few birds.  With regard to
animals, it is a most remarkable fact, that so large an island,
extending over more than 700 miles in latitude, and in many parts
ninety broad, with varied stations, a fine climate, and land of all
heights, from 14,000 feet downwards, with the exception of a small rat,
did not possess one indigenous animal. The several species of that
gigantic genus of birds, the Deinornis seem here to have replaced
mammiferous quadrupeds, in the same manner as the reptiles still do at
the Galapagos archipelago.  It is said that the common Norway rat, in
the short space of two years, annihilated in this northern end of the
island, the New Zealand species.  In many places I noticed several
sorts of weeds, which, like the rats, I was forced to own as
countrymen.  A leek has overrun whole districts, and will prove very
troublesome, but it was imported as a favour by a French vessel.  The
common dock is also widely disseminated, and will, I fear, for ever
remain a proof of the rascality of an Englishman, who sold the seeds
for those of the tobacco plant.

On returning from our pleasant walk to the house, I dined with Mr.
Williams; and then, a horse being lent me, I returned to the Bay of
Islands.  I took leave of the missionaries with thankfulness for their
kind welcome, and with feelings of high respect for their
gentlemanlike, useful, and upright characters.  I think it would be
difficult to find a body of men better adapted for the high office
which they fulfil.

Christmas Day.--In a few more days the fourth year of our absence from
England will be completed.  Our first Christmas Day was spent at
Plymouth, the second at St. Martin's Cove, near Cape Horn; the third at
Port Desire, in Patagonia; the fourth at anchor in a wild harbour in
the peninsula of Tres Montes, this fifth here, and the next, I trust in
Providence, will be in England.  We attended divine service in the
chapel of Pahia; part of the service being read in English, and part in
the native language.  Whilst at New Zealand we did not hear of any
recent acts of cannibalism; but Mr. Stokes found burnt human bones
strewed round a fire-place on a small island near the anchorage; but
these remains of a comfortable banquet might have been lying there for
several years.  It is probable that the moral state of the people will
rapidly improve.  Mr. Bushby mentioned one pleasing anecdote as a proof
of the sincerity of some, at least, of those who profess Christianity.
One of his young men left him, who had been accustomed to read prayers
to the rest of the servants.  Some weeks afterwards, happening to pass
late in the evening by an outhouse, he saw and heard one of his men
reading the Bible with difficulty by the light of the fire, to the
others.  After this the party knelt and prayed: in their prayers they
mentioned Mr. Bushby and his family, and the missionaries, each
separately in his respective district.

December 26th.--Mr. Bushby offered to take Mr. Sulivan and myself in
his boat some miles up the river to Cawa-Cawa, and proposed afterwards
to walk on to the village of Waiomio, where there are some curious
rocks.  Following one of the arms of the bay, we enjoyed a pleasant
row, and passed through pretty scenery, until we came to a village,
beyond which the boat could not pass.  From this place a chief and a
party of men volunteered to walk with us to Waiomio, a distance of four
miles.  The chief was at this time rather notorious from having lately
hung one of his wives and a slave for adultery.  When one of the
missionaries remonstrated with him he seemed surprised, and said he
thought he was exactly following the English method. Old Shongi, who
happened to be in England during the Queen's trial, expressed great
disapprobation at the whole proceeding: he said he had five wives, and
he would rather cut off all their heads than be so much troubled about
one. Leaving this village, we crossed over to another, seated on a
hill-side at a little distance.  The daughter of a chief, who was still
a heathen, had died there five days before.  The hovel in which she had
expired had been burnt to the ground: her body being enclosed between
two small canoes, was placed upright on the ground, and protected by an
enclosure bearing wooden images of their gods, and the whole was
painted bright red, so as to be conspicuous from afar.  Her gown was
fastened to the coffin, and her hair being cut off was cast at its
foot.  The relatives of the family had torn the flesh of their arms,
bodies, and faces, so that they were covered with clotted blood; and
the old women looked most filthy, disgusting objects.  On the following
day some of the officers visited this place, and found the women still
howling and cutting themselves.

We continued our walk, and soon reached Waiomio.  Here there are some
singular masses of limestone, resembling ruined castles.  These rocks
have long served for burial places, and in consequence are held too
sacred to be approached. One of the young men, however, cried out, "Let
us all be brave," and ran on ahead; but when within a hundred yards,
the whole party thought better of it, and stopped short.  With perfect
indifference, however, they allowed us to examine the whole place.  At
this village we rested some hours, during which time there was a long
discussion with Mr. Bushby, concerning the right of sale of certain
lands. One old man, who appeared a perfect genealogist, illustrated the
successive possessors by bits of stick driven into the ground.  Before
leaving the houses a little basketful of roasted sweet potatoes was
given to each of our party; and we all, according to the custom,
carried them away to eat on the road.  I noticed that among the women
employed in cooking, there was a man-slave: it must be a humiliating
thing for a man in this warlike country to be employed in doing that
which is considered as the lowest woman's work. Slaves are not allowed
to go to war; but this perhaps can hardly be considered as a hardship.
I heard of one poor wretch who, during hostilities, ran away to the
opposite party; being met by two men, he was immediately seized; but as
they could not agree to whom he should belong, each stood over him with
a stone hatchet, and seemed determined that the other at least should
not take him away alive.  The poor man, almost dead with fright, was
only saved by the address of a chief's wife.  We afterwards enjoyed a
pleasant walk back to the boat, but did not reach the ship till late in
the evening.

December 30th.--In the afternoon we stood out of the Bay of Islands, on
our course to Sydney.  I believe we were all glad to leave New Zealand.
It is not a pleasant place. Amongst the natives there is absent that
charming simplicity which is found in Tahiti; and the greater part of
the English are the very refuse of society.  Neither is the country
itself attractive.  I look back but to one bright spot, and that is
Waimate, with its Christian inhabitants.



CHAPTER XIX

AUSTRALIA

Sydney--Excursion to Bathurst--Aspect of the Woods--Party of
Natives--Gradual Extinction of the Aborigines--Infection generated by
associated Men in health--Blue Mountains--View of the grand gulf-like
Valleys--Their origin and formation--Bathurst, general civility of the
Lower Orders--State of Society--Van Diemen's Land--Hobart
Town--Aborigines all banished--Mount Wellington--King George's
Sound--Cheerless Aspect of the Country--Bald Head, calcareous casts of
branches of Trees--Party of Natives--Leave Australia.


JANUARY 12th, 1836.--Early in the morning a light air carried us
towards the entrance of Port Jackson.  Instead of beholding a verdant
country, interspersed with fine houses, a straight line of yellowish
cliff brought to our minds the coast of Patagonia.  A solitary
lighthouse, built of white stone, alone told us that we were near a
great and populous city.  Having entered the harbour, it appears fine
and spacious, with cliff-formed shores of horizontally stratified
sandstone.  The nearly level country is covered with thin scrubby
trees, bespeaking the curse of sterility. Proceeding further inland,
the country improves: beautiful villas and nice cottages are here and
there scattered along the beach.  In the distance stone houses, two and
three stories high, and windmills standing on the edge of a bank,
pointed out to us the neighbourhood of the capital of Australia.

At last we anchored within Sydney Cove.  We found the little basin
occupied by many large ships, and surrounded by warehouses.  In the
evening I walked through the town, and returned full of admiration at
the whole scene.  It is a most magnificent testimony to the power of
the British nation. Here, in a less promising country, scores of years
have done many more times more than an equal number of centuries have
effected in South America.  My first feeling was to congratulate myself
that I was born an Englishman.  Upon seeing more of the town
afterwards, perhaps my admiration fell a little; but yet it is a fine
town.  The streets are regular, broad, clean, and kept in excellent
order; the houses are of a good size, and the shops well furnished.  It
may be faithfully compared to the large suburbs which stretch out from
London and a few other great towns in England; but not even near London
or Birmingham is there an appearance of such rapid growth.  The number
of large houses and other buildings just finished was truly surprising;
nevertheless, every one complained of the high rents and difficulty in
procuring a house.  Coming from South America, where in the towns every
man of property is known, no one thing surprised me more than not being
able to ascertain at once to whom this or that carriage belonged.

I hired a man and two horses to take me to Bathurst, a village about
one hundred and twenty miles in the interior, and the centre of a great
pastoral district.  By this means I hoped to gain a general idea of the
appearance of the country. On the morning of the 16th (January) I set
out on my excursion. The first stage took us to Paramatta, a small
country town, next to Sydney in importance.  The roads were excellent,
and made upon the MacAdam principle, whinstone having been brought for
the purpose from the distance of several miles.  In all respects there
was a close resemblance to England: perhaps the alehouses here were
more numerous.  The iron gangs, or parties of convicts who have
committed here some offense, appeared the least like England: they were
working in chains, under the charge of sentries with loaded arms.

The power which the government possesses, by means of forced labour, of
at once opening good roads throughout the country, has been, I believe,
one main cause of the early prosperity of this colony.  I slept at
night at a very comfortable inn at Emu ferry, thirty-five miles from
Sydney, and near the ascent of the Blue Mountains.  This line of road
is the most frequented, and has been the longest inhabited of any in
the colony.  The whole land is enclosed with high railings, for the
farmers have not succeeded in rearing hedges.  There are many
substantial houses and good cottages scattered about; but although
considerable pieces of land are under cultivation, the greater part yet
remains as when first discovered.

The extreme uniformity of the vegetation is the most remarkable feature
in the landscape of the greater part of New South Wales.  Everywhere we
have an open woodland, the ground being partially covered with a very
thin pasture, with little appearance of verdure.  The trees nearly all
belong to one family, and mostly have their leaves placed in a
vertical, instead of as in Europe, in a nearly horizontal position: the
foliage is scanty, and of a peculiar pale green tint, without any
gloss.  Hence the woods appear light and shadowless: this, although a
loss of comfort to the traveller under the scorching rays of summer, is
of importance to the farmer, as it allows grass to grow where it
otherwise would not.  The leaves are not shed periodically: this
character appears common to the entire southern hemisphere, namely,
South America, Australia, and the Cape of Good Hope.  The inhabitants
of this hemisphere, and of the intertropical regions, thus lose perhaps
one of the most glorious, though to our eyes common, spectacles in the
world--the first bursting into full foliage of the leafless tree. They
may, however, say that we pay dearly for this by having the land
covered with mere naked skeletons for so many months.  This is too true
but our senses thus acquire a keen relish for the exquisite green of
the spring, which the eyes of those living within the tropics, sated
during the long year with the gorgeous productions of those glowing
climates, can never experience. The greater number of the trees, with
the exception of some of the Blue-gums, do not attain a large size; but
they grow tall and tolerably straight, and stand well apart.  The bark
of some of the Eucalypti falls annually, or hangs dead in long shreds
which swing about with the wind, and give to the woods a desolate and
untidy appearance.  I cannot imagine a more complete contrast, in every
respect, than between the forests of Valdivia or Chiloe, and the woods
of Australia.

At sunset, a party of a score of the black aborigines passed by, each
carrying, in their accustomed manner, a bundle of spears and other
weapons.  By giving a leading young man a shilling, they were easily
detained, and threw their spears for my amusement.  They were all
partly clothed, and several could speak a little English: their
countenances were good-humoured and pleasant, and they appeared far
from being such utterly degraded beings as they have usually been
represented.  In their own arts they are admirable.  A cap being fixed
at thirty yards distance, they transfixed it with a spear, delivered by
the throwing-stick with the rapidity of an arrow from the bow of a
practised archer.  In tracking animals or men they show most wonderful
sagacity; and I heard of several of their remarks which manifested
considerable acuteness. They will not, however, cultivate the ground,
or build houses and remain stationary, or even take the trouble of
tending a flock of sheep when given to them.  On the whole they appear
to me to stand some few degrees higher in the scale of civilization
than the Fuegians.

It is very curious thus to see in the midst of a civilized people, a
set of harmless savages wandering about without knowing where they
shall sleep at night, and gaining their livelihood by hunting in the
woods.  As the white man has travelled onwards, he has spread over the
country belonging to several tribes.  These, although thus enclosed by
one common people, keep up their ancient distinctions, and sometimes go
to war with each other.  In an engagement which took place lately, the
two parties most singularly chose the centre of the village of Bathurst
for the field of battle.  This was of service to the defeated side, for
the runaway warriors took refuge in the barracks.

The number of aborigines is rapidly decreasing.  In my whole ride, with
the exception of some boys brought up by Englishmen, I saw only one
other party.  This decrease, no doubt, must be partly owing to the
introduction of spirits, to European diseases (even the milder ones of
which, such as the measles, [1] prove very destructive), and to the
gradual extinction of the wild animals.  It is said that numbers of
their children invariably perish in very early infancy from the effects
of their wandering life; and as the difficulty of procuring food
increases, so must their wandering habits increase; and hence the
population, without any apparent deaths from famine, is repressed in a
manner extremely sudden compared to what happens in civilized
countries, where the father, though in adding to his labour he may
injure himself, does not destroy his offspring.

Besides the several evident causes of destruction, there appears to be
some more mysterious agency generally at work.  Wherever the European
has trod, death seems to pursue the aboriginal.  We may look to the
wide extent of the Americas, Polynesia, the Cape of Good Hope, and
Australia, and we find the same result.  Nor is it the white man alone
that thus acts the destroyer; the Polynesian of Malay extraction has in
parts of the East Indian archipelago, thus driven before him the
dark-coloured native.  The varieties of man seem to act on each other
in the same way as different species of animals--the stronger always
extirpating the weaker.  It was melancholy at New Zealand to hear the
fine energetic natives saying that they knew the land was doomed to
pass from their children.  Every one has heard of the inexplicable
reduction of the population in the beautiful and healthy island of
Tahiti since the date of Captain Cook's voyages: although in that case
we might have expected that it would have been increased; for
infanticide, which formerly prevailed to so extraordinary a degree, has
ceased; profligacy has greatly diminished, and the murderous wars
become less frequent.

The Rev. J. Williams, in his interesting work, [2] says, that the first
intercourse between natives and Europeans, "is invariably attended with
the introduction of fever, dysentery, or some other disease, which
carries off numbers of the people." Again he affirms, "It is certainly
a fact, which cannot be controverted, that most of the diseases which
have raged in the islands during my residence there, have been
introduced by ships; [3] and what renders this fact remarkable is, that
there might be no appearance of disease among the crew of the ship
which conveyed this destructive importation." This statement is not
quite so extraordinary as it at first appears; for several cases are on
record of the most malignant fevers having broken out, although the
parties themselves, who were the cause, were not affected.  In the
early part of the reign of George III., a prisoner who had been
confined in a dungeon, was taken in a coach with four constables before
a magistrate; and although the man himself was not ill, the four
constables died from a short putrid fever; but the contagion extended
to no others.  From these facts it would almost appear as if the
effluvium of one set of men shut up for some time together was
poisonous when inhaled by others; and possibly more so, if the men be
of different races.  Mysterious as this circumstance appears to be, it
is not more surprising than that the body of one's fellow-creature,
directly after death, and before putrefaction has commenced, should
often be of so deleterious a quality, that the mere puncture from an
instrument used in its dissection, should prove fatal.

17th.--Early in the morning we passed the Nepean in a ferry-boat. The
river, although at this spot both broad and deep, had a very small body
of running water.  Having crossed a low piece of land on the opposite
side, we reached the slope of the Blue Mountains.  The ascent is not
steep, the road having been cut with much care on the side of a
sandstone cliff.  On the summit an almost level plain extends, which,
rising imperceptibly to the westward, at last attains a height of more
than 3000 feet.  From so grand a title as Blue Mountains, and from
their absolute altitude, I expected to have seen a bold chain of
mountains crossing the country; but instead of this, a sloping plain
presents merely an inconsiderable front to the low land near the coast.
From this first slope, the view of the extensive woodland to the east
was striking, and the surrounding trees grew bold and lofty.  But when
once on the sandstone platform, the scenery becomes exceedingly
monotonous; each side of the road is bordered by scrubby trees of the
never-failing Eucalyptus family; and with the exception of two or three
small inns, there are no houses or cultivated land: the road, moreover,
is solitary; the most frequent object being a bullock-waggon, piled up
with bales of wool.

In the middle of the day we baited our horses at a little inn, called
the Weatherboard.  The country here is elevated 2800 feet above the
sea.  About a mile and a half from this place there is a view
exceedingly well worth visiting.  Following down a little valley and
its tiny rill of water, an immense gulf unexpectedly opens through the
trees which border the pathway, at the depth of perhaps 1500 feet.
Walking on a few yards, one stands on the brink of a vast precipice,
and below one sees a grand bay or gulf, for I know not what other name
to give it, thickly covered with forest. The point of view is situated
as if at the head of a bay, the line of cliff diverging on each side,
and showing headland behind headland, as on a bold sea-coast.  These
cliffs are composed of horizontal strata of whitish sandstone; and are
so absolutely vertical, that in many places a person standing on the
edge and throwing down a stone, can see it strike the trees in the
abyss below.  So unbroken is the line of cliff, that in order to reach
the foot of the waterfall, formed by this little stream, it is said to
be necessary to go sixteen miles round.  About five miles distant in
front, another line of cliff extends, which thus appears completely to
encircle the valley; and hence the name of bay is justified, as applied
to this grand amphitheatrical depression.  If we imagine a winding
harbour, with its deep water surrounded by bold cliff-like shores, to
be laid dry, and a forest to spring up on its sandy bottom, we should
then have the appearance and structure here exhibited.  This kind of
view was to me quite novel, and extremely magnificent.

In the evening we reached the Blackheath.  The sandstone plateau has
here attained the height of 3400 feet; and is covered, as before, with
the same scrubby woods.  From the road, there were occasional glimpses
into a profound valley, of the same character as the one described; but
from the steepness and depth of its sides, the bottom was scarcely ever
to be seen.  The Blackheath is a very comfortable inn, kept by an old
soldier; and it reminded me of the small inns in North Wales.

18th.--Very early in the morning, I walked about three miles to see
Govett's Leap; a view of a similar character with that near the
Weatherboard, but perhaps even more stupendous.  So early in the day
the gulf was filled with a thin blue haze, which, although destroying
the general effect of the view added to the apparent depth at which the
forest was stretched out beneath our feet.  These valleys, which so
long presented an insuperable barrier to the attempts of the most
enterprising of the colonists to reach the interior, are most
remarkable.  Great arm-like bays, expanding at their upper ends, often
branch from the main valleys and penetrate the sandstone platform; on
the other hand, the platform often sends promontories into the valleys,
and even leaves in them great, almost insulated, masses.  To descend
into some of these valleys, it is necessary to go round twenty miles;
and into others, the surveyors have only lately penetrated, and the
colonists have not yet been able to drive in their cattle.  But the
most remarkable feature in their structure is, that although several
miles wide at their heads, they generally contract towards their mouths
to such a degree as to become impassable.  The Surveyor-General, Sir T.
Mitchell, [4] endeavoured in vain, first walking and then by crawling
between the great fallen fragments of sandstone, to ascend through the
gorge by which the river Grose joins the Nepean, yet the valley of the
Grose in its upper part, as I saw, forms a magnificent level basin some
miles in width, and is on all sides surrounded by cliffs, the summits
of which are believed to be nowhere less than 3000 feet above the level
of the sea.  When cattle are driven into the valley of the Wolgan by a
path (which I descended), partly natural and partly made by the owner
of the land, they cannot escape; for this valley is in every other part
surrounded by perpendicular cliffs, and eight miles lower down, it
contracts from an average width of half a mile, to a mere chasm,
impassable to man or beast.  Sir T. Mitchell states that the great
valley of the Cox river with all its branches, contracts, where it
unites with the Nepean, into a gorge 2200 yards in width, and about
1000 feet in depth.  Other similar cases might have been added.

The first impression, on seeing the correspondence of the horizontal
strata on each side of these valleys and great amphitheatrical
depressions, is that they have been hollowed out, like other valleys,
by the action of water; but when one reflects on the enormous amount of
stone, which on this view must have been removed through mere gorges or
chasms, one is led to ask whether these spaces may not have subsided.
But considering the form of the irregularly branching valleys, and of
the narrow promontories projecting into them from the platforms, we are
compelled to abandon this notion.  To attribute these hollows to the
present alluvial action would be preposterous; nor does the drainage
from the summit-level always fall, as I remarked near the Weatherboard,
into the head of these valleys, but into one side of their bay-like
recesses.  Some of the inhabitants remarked to me that they never
viewed one of those bay-like recesses, with the headlands receding on
both hands, without being struck with their resemblance to a bold
sea-coast.  This is certainly the case; moreover, on the present coast
of New South Wales, the numerous, fine, widely-branching harbours,
which are generally connected with the sea by a narrow mouth worn
through the sandstone coast-cliffs, varying from one mile in width to a
quarter of a mile, present a likeness, though on a miniature scale, to
the great valleys of the interior.  But then immediately occurs the
startling difficulty, why has the sea worn out these great, though
circumscribed depressions on a wide platform, and left mere gorges at
the openings, through which the whole vast amount of triturated matter
must have been carried away?  The only light I can throw upon this
enigma, is by remarking that banks of the most irregular forms appear
to be now forming in some seas, as in parts of the West Indies and in
the Red Sea, and that their sides are exceedingly steep.  Such banks, I
have been led to suppose, have been formed by sediment heaped by strong
currents on an irregular bottom.  That in some cases the sea, instead
of spreading out sediment in a uniform sheet, heaps it round submarine
rocks and islands, it is hardly possible to doubt, after examining the
charts of the West Indies; and that the waves have power to form high
and precipitous cliffs, even in land-locked harbours, I have noticed in
many parts of South America.  To apply these ideas to the sandstone
platforms of New South Wales, I imagine that the strata were heaped by
the action of strong currents, and of the undulations of an open sea,
on an irregular bottom; and that the valley-like spaces thus left
unfilled had their steeply sloping flanks worn into cliffs, during a
slow elevation of the land; the worn-down sandstone being removed,
either at the time when the narrow gorges were cut by the retreating
sea, or subsequently by alluvial action.


Soon after leaving the Blackheath, we descended from the sandstone
platform by the pass of Mount Victoria.  To effect this pass, an
enormous quantity of stone has been cut through; the design, and its
manner of execution, being worthy of any line of road in England.  We
now entered upon a country less elevated by nearly a thousand feet, and
consisting of granite.  With the change of rock, the vegetation
improved, the trees were both finer and stood farther apart; and the
pasture between them was a little greener and more plentiful.  At
Hassan's Walls, I left the high road, and made a short detour to a farm
called Walerawang; to the superintendent of which I had a letter of
introduction from the owner in Sydney.  Mr. Browne had the kindness to
ask me to stay the ensuing day, which I had much pleasure in doing.
This place offers an example of one of the large farming, or rather
sheep-grazing establishments of the colony.  Cattle and horses are,
however, in this case rather more numerous than usual, owing to some of
the valleys being swampy and producing a coarser pasture.  Two or three
flat pieces of ground near the house were cleared and cultivated with
corn, which the harvest-men were now reaping: but no more wheat is sown
than sufficient for the annual support of the labourers employed on the
establishment.  The usual number of assigned convict-servants here is
about forty, but at the present time there were rather more.  Although
the farm was well stocked with every necessary, there was an apparent
absence of comfort; and not one single woman resided here.  The sunset
of a fine day will generally cast an air of happy contentment on any
scene; but here, at this retired farm-house, the brightest tints on the
surrounding woods could not make me forget that forty hardened,
profligate men were ceasing from their daily labours, like the slaves
from Africa, yet without their holy claim for compassion.

Early on the next morning, Mr. Archer, the joint superintendent, had
the kindness to take me out kangaroo-hunting. We continued riding the
greater part of the day, but had very bad sport, not seeing a kangaroo,
or even a wild dog. The greyhounds pursued a kangaroo rat into a hollow
tree, out of which we dragged it: it is an animal as large as a rabbit,
but with the figure of a kangaroo.  A few years since this country
abounded with wild animals; but now the emu is banished to a long
distance, and the kangaroo is become scarce; to both the English
greyhound has been highly destructive.  It may be long before these
animals are altogether exterminated, but their doom is fixed.  The
aborigines are always anxious to borrow the dogs from the farm-houses:
the use of them, the offal when an animal is killed, and some milk from
the cows, are the peace-offerings of the settlers, who push farther and
farther towards the interior.  The thoughtless aboriginal, blinded by
these trifling advantages, is delighted at the approach of the white
man, who seems predestined to inherit the country of his children.

Although having poor sport, we enjoyed a pleasant ride. The woodland is
generally so open that a person on horseback can gallop through it.  It
is traversed by a few flat-bottomed valleys, which are green and free
from trees: in such spots the scenery was pretty like that of a park.
In the whole country I scarcely saw a place without the marks of a
fire; whether these had been more or less recent--whether the stumps
were more or less black, was the greatest change which varied the
uniformity, so wearisome to the traveller's eye.  In these woods there
are not many birds; I saw, however, some large flocks of the white
cockatoo feeding in a corn-field, and a few most beautiful parrots;
crows, like our jackdaws were not uncommon, and another bird something
like the magpie.  In the dusk of the evening I took a stroll along a
chain of ponds, which in this dry country represented the course of a
river, and had the good fortune to see several of the famous
Ornithorhynchus paradoxus.  They were diving and playing about the
surface of the water, but showed so little of their bodies, that they
might easily have been mistaken for water-rats.  Mr. Browne shot one:
certainly it is a most extraordinary animal; a stuffed specimen does
not at all give a good idea of the appearance of the head and beak when
fresh; the latter becoming hard and contracted. [5]

20th.--A long day's ride to Bathurst.  Before joining the highroad we
followed a mere path through the forest; and the country, with the
exception of a few squatters' huts, was very solitary.  We experienced
this day the sirocco-like wind of Australia, which comes from the
parched deserts of the interior.  Clouds of dust were travelling in
every direction; and the wind felt as if it had passed over a fire.  I
afterwards heard that the thermometer out of doors had stood at 119
degs., and in a closed room at 96 degs.  In the afternoon we came in
view of the downs of Bathurst.  These undulating but nearly smooth
plains are very remarkable in this country, from being absolutely
destitute of trees.  They support only a thin brown pasture.  We rode
some miles over this country, and then reached the township of
Bathurst, seated in the middle of what may be called either a very
broad valley, or narrow plain.  I was told at Sydney not to form too
bad an opinion of Australia by judging of the country from the
roadside, nor too good a one from Bathurst; in this latter respect, I
did not feel myself in the least danger of being prejudiced.  The
season, it must be owned, had been one of great drought, and the
country did not wear a favourable aspect; although I understand it was
incomparably worse two or three months before.  The secret of the
rapidly growing prosperity of Bathurst is, that the brown pasture which
appears to the stranger's eye so wretched, is excellent for
sheep-grazing.  The town stands, at the height of 2200 feet above the
sea, on the banks of the Macquarie.  This is one of the rivers flowing
into the vast and scarcely known interior. The line of water-shed,
which divides the inland streams from those on the coast, has a height
of about 3000 feet, and runs in a north and south direction at the
distance of from eighty to a hundred miles from the sea-side.  The
Macquarie figures in the map as a respectable river, and it is the
largest of those draining this part of the water-shed; yet to my
surprise I found it a mere chain of ponds, separated from each other by
spaces almost dry.  Generally a small stream is running; and sometimes
there are high and impetuous floods.  Scanty as the supply of the water
is throughout this district, it becomes still scantier further inland.

22nd.--I commenced my return, and followed a new road called Lockyer's
Line, along which the country is rather more hilly and picturesque.
This was a long day's ride; and the house where I wished to sleep was
some way off the road, and not easily found.  I met on this occasion,
and indeed on all others, a very general and ready civility among the
lower orders, which, when one considers what they are, and what they
have been, would scarcely have been expected.  The farm where I passed
the night, was owned by two young men who had only lately come out, and
were beginning a settler's life.  The total want of almost every
comfort was not attractive; but future and certain prosperity was
before their eyes, and that not far distant.

The next day we passed through large tracts of country in flames,
volumes of smoke sweeping across the road.  Before noon we joined our
former road, and ascended Mount Victoria. I slept at the Weatherboard,
and before dark took another walk to the amphitheatre.  On the road to
Sydney I spent a very pleasant evening with Captain King at Dunheved;
and thus ended my little excursion in the colony of New South Wales.

Before arriving here the three things which interested me most
were--the state of society amongst the higher classes, the condition of
the convicts, and the degree of attraction sufficient to induce persons
to emigrate.  Of course, after so very short a visit, one's opinion is
worth scarcely anything; but it is as difficult not to form some
opinion, as it is to form a correct judgment.  On the whole, from what
I heard, more than from what I saw, I was disappointed in the state of
society.  The whole community is rancorously divided into parties on
almost every subject.  Among those who, from their station in life,
ought to be the best, many live in such open profligacy that
respectable people cannot associate with them.  There is much jealousy
between the children of the rich emancipist and the free settlers, the
former being pleased to consider honest men as interlopers. The whole
population, poor and rich, are bent on acquiring wealth: amongst the
higher orders, wool and sheep-grazing form the constant subject of
conversation.  There are many serious drawbacks to the comforts of a
family, the chief of which, perhaps, is being surrounded by convict
servants. How thoroughly odious to every feeling, to be waited on by a
man who the day before, perhaps, was flogged, from your representation,
for some trifling misdemeanor.  The female servants are of course, much
worse: hence children learn the vilest expressions, and it is
fortunate, if not equally vile ideas.

On the other hand, the capital of a person, without any trouble on his
part, produces him treble interest to what it will in England; and with
care he is sure to grow rich.  The luxuries of life are in abundance,
and very little dearer than in England, and most articles of food are
cheaper.  The climate is splendid, and perfectly healthy; but to my
mind its charms are lost by the uninviting aspect of the country.
Settlers possess a great advantage in finding their sons of service
when very young.  At the age of from sixteen to twenty, they frequently
take charge of distant farming stations. This, however, must happen at
the expense of their boys associating entirely with convict servants. I
am not aware that the tone of society has assumed any peculiar
character; but with such habits, and without intellectual pursuits, it
can hardly fail to deteriorate.  My opinion is such, that nothing but
rather sharp necessity should compel me to emigrate.

The rapid prosperity and future prospects of this colony are to me, not
understanding these subjects, very puzzling. The two main exports are
wool and whale-oil, and to both of these productions there is a limit.
The country is totally unfit for canals, therefore there is a not very
distant point, beyond which the land-carriage of wool will not repay
the expense of shearing and tending sheep.  Pasture everywhere is so
thin that settlers have already pushed far into the interior: moreover,
the country further inland becomes extremely poor.  Agriculture, on
account of the droughts, can never succeed on an extended scale:
therefore, so far as I can see, Australia must ultimately depend upon
being the centre of commerce for the southern hemisphere, and perhaps
on her future manufactories.  Possessing coal, she always has the
moving power at hand.  From the habitable country extending along the
coast, and from her English extraction, she is sure to be a maritime
nation.  I formerly imagined that Australia would rise to be as grand
and powerful a country as North America, but now it appears to me that
such future grandeur is rather problematical.

With respect to the state of the convicts, I had still fewer
opportunities of judging than on other points.  The first question is,
whether their condition is at all one of punishment: no one will
maintain that it is a very severe one. This, however, I suppose, is of
little consequence as long as it continues to be an object of dread to
criminals at home. The corporeal wants of the convicts are tolerably
well supplied: their prospect of future liberty and comfort is not
distant, and, after good conduct, certain.  A "ticket of leave," which,
as long as a man keeps clear of suspicion as well as of crime, makes
him free within a certain district, is given upon good conduct, after
years proportional to the length of the sentence; yet with all this,
and overlooking the previous imprisonment and wretched passage out, I
believe the years of assignment are passed away with discontent and
unhappiness.  As an intelligent man remarked to me, the convicts know
no pleasure beyond sensuality, and in this they are not gratified.  The
enormous bribe which Government possesses in offering free pardons,
together with the deep horror of the secluded penal settlements,
destroys confidence between the convicts, and so prevents crime.  As to
a sense of shame, such a feeling does not appear to be known, and of
this I witnessed some very singular proofs.  Though it is a curious
fact, I was universally told that the character of the convict
population is one of arrant cowardice: not unfrequently some become
desperate, and quite indifferent as to life, yet a plan requiring cool
or continued courage is seldom put into execution.  The worst feature
in the whole case is, that although there exists what may be called a
legal reform, and comparatively little is committed which the law can
touch, yet that any moral reform should take place appears to be quite
out of the question.  I was assured by well-informed people, that a man
who should try to improve, could not while living with other assigned
servants;--his life would be one of intolerable misery and persecution.
Nor must the contamination of the convict-ships and prisons, both here
and in England, be forgotten.  On the whole, as a place of punishment,
the object is scarcely gained; as a real system of reform it has
failed, as perhaps would every other plan; but as a means of making men
outwardly honest,--of converting vagabonds, most useless in one
hemisphere, into active citizens of another, and thus giving birth to a
new and splendid country--a grand centre of civilization--it has
succeeded to a degree perhaps unparalleled in history.


30th.--The Beagle sailed for Hobart Town in Van Diemen's Land.  On the
5th of February, after a six days' passage, of which the first part was
fine, and the latter very cold and squally, we entered the mouth of
Storm Bay: the weather justified this awful name.  The bay should
rather be called an estuary, for it receives at its head the waters of
the Derwent.  Near the mouth, there are some extensive basaltic
platforms; but higher up the land becomes mountainous, and is covered
by a light wood.  The lower parts of the hills which skirt the bay are
cleared; and the bright yellow fields of corn, and dark green ones of
potatoes, appear very luxuriant. Late in the evening we anchored in the
snug cove, on the shores of which stands the capital of Tasmania.  The
first aspect of the place was very inferior to that of Sydney; the
latter might be called a city, this is only a town.  It stands at the
base of Mount Wellington, a mountain 3100 feet high, but of little
picturesque beauty; from this source, however, it receives a good
supply of water.  Round the cove there are some fine warehouses and on
one side a small fort. Coming from the Spanish settlements, where such
magnificent care has generally been paid to the fortifications, the
means of defence in these colonies appeared very contemptible.
Comparing the town with Sydney, I was chiefly struck with the
comparative fewness of the large houses, either built or building.
Hobart Town, from the census of 1835, contained 13,826 inhabitants, and
the whole of Tasmania 36,505.

All the aborigines have been removed to an island in Bass's Straits, so
that Van Diemen's Land enjoys the great advantage of being free from a
native population.  This most cruel step seems to have been quite
unavoidable, as the only means of stopping a fearful succession of
robberies, burnings, and murders, committed by the blacks; and which
sooner or later would have ended in their utter destruction. I fear
there is no doubt, that this train of evil and its consequences,
originated in the infamous conduct of some of our countrymen.  Thirty
years is a short period, in which to have banished the last aboriginal
from his native island,--and that island nearly as large as Ireland.
The correspondence on this subject, which took place between the
government at home and that of Van Diemen's Land, is very interesting.
Although numbers of natives were shot and taken prisoners in the
skirmishing, which was going on at intervals for several years; nothing
seems fully to have impressed them with the idea of our overwhelming
power, until the whole island, in 1830, was put under martial law, and
by proclamation the whole population commanded to assist in one great
attempt to secure the entire race.  The plan adopted was nearly similar
to that of the great hunting-matches in India: a line was formed
reaching across the island, with the intention of driving the natives
into a _cul-de-sac_ on Tasman's peninsula. The attempt failed; the
natives, having tied up their dogs, stole during one night through the
lines.  This is far from surprising, when their practised senses, and
usual manner of crawling after wild animals is considered.  I have been
assured that they can conceal themselves on almost bare ground, in a
manner which until witnessed is scarcely credible; their dusky bodies
being easily mistaken for the blackened stumps which are scattered all
over the country.  I was told of a trial between a party of Englishmen
and a native, who was to stand in full view on the side of a bare hill;
if the Englishmen closed their eyes for less than a minute, he would
squat down, and then they were never able to distinguish him from the
surrounding stumps.  But to return to the hunting-match; the natives
understanding this kind of warfare, were terribly alarmed, for they at
once perceived the power and numbers of the whites.  Shortly afterwards
a party of thirteen belonging to two tribes came in; and, conscious of
their unprotected condition, delivered themselves up in despair.
Subsequently by the intrepid exertions of Mr. Robinson, an active and
benevolent man, who fearlessly visited by himself the most hostile of
the natives, the whole were induced to act in a similar manner.  They
were then removed to an island, where food and clothes were provided
them.  Count Strzelecki states, [6] that "at the epoch of their
deportation in 1835, the number of natives amounted to 210.  In 1842,
that is, after the interval of seven years, they mustered only
fifty-four individuals; and, while each family of the interior of New
South Wales, uncontaminated by contact with the whites, swarms with
children, those of Flinders' Island had during eight years an accession
of only fourteen in number!"

The Beagle stayed here ten days, and in this time I made several
pleasant little excursions, chiefly with the object of examining the
geological structure of the immediate neighbourhood.  The main points
of interest consist, first in some highly fossiliferous strata,
belonging to the Devonian or Carboniferous period; secondly, in proofs
of a late small rise of the land; and lastly, in a solitary and
superficial patch of yellowish limestone or travertin, which contains
numerous impressions of leaves of trees, together with land-shells, not
now existing.  It is not improbable that this one small quarry includes
the only remaining record of the vegetation of Van Diemen's Land during
one former epoch.

The climate here is damper than in New South Wales, and hence the land
is more fertile.  Agriculture flourishes; the cultivated fields look
well, and the gardens abound with thriving vegetables and fruit-trees.
Some of the farm-houses, situated in retired spots, had a very
attractive appearance. The general aspect of the vegetation is similar
to that of Australia; perhaps it is a little more green and cheerful;
and the pasture between the trees rather more abundant.  One day I took
a long walk on the side of the bay opposite to the town: I crossed in a
steam-boat, two of which are constantly plying backwards and forwards.
The machinery of one of these vessels was entirely manufactured in this
colony, which, from its very foundation, then numbered only three and
thirty years!  Another day I ascended Mount Wellington; I took with me
a guide, for I failed in a first attempt, from the thickness of the
wood.  Our guide, however, was a stupid fellow, and conducted us to the
southern and damp side of the mountain, where the vegetation was very
luxuriant; and where the labour of the ascent, from the number of
rotten trunks, was almost as great as on a mountain in Tierra del Fuego
or in Chiloe.  It cost us five and a half hours of hard climbing before
we reached the summit. In many parts the Eucalypti grew to a great
size, and composed a noble forest.  In some of the dampest ravines,
tree-ferns flourished in an extraordinary manner; I saw one which must
have been at least twenty feet high to the base of the fronds, and was
in girth exactly six feet.  The fronds forming the most elegant
parasols, produced a gloomy shade, like that of the first hour of the
night.  The summit of the mountain is broad and flat, and is composed
of huge angular masses of naked greenstone.  Its elevation is 3100 feet
above the level of the sea.  The day was splendidly clear, and we
enjoyed a most extensive view; to the north, the country appeared a
mass of wooded mountains, of about the same height with that on which
we were standing, and with an equally tame outline: to the south the
broken land and water, forming many intricate bays, was mapped with
clearness before us.  After staying some hours on the summit, we found
a better way to descend, but did not reach the Beagle till eight
o'clock, after a severe day's work.

February 7th.--The Beagle sailed from Tasmania, and, on the 6th of the
ensuing month, reached King George's Sound, situated close to the S. W.
corner of Australia.  We stayed there eight days; and we did not during
our voyage pass a more dull and uninteresting time.  The country,
viewed from an eminence, appears a woody plain, with here and there
rounded and partly bare hills of granite protruding. One day I went out
with a party, in hopes of seeing a kangaroo hunt, and walked over a
good many miles of country. Everywhere we found the soil sandy, and
very poor; it supported either a coarse vegetation of thin, low
brushwood and wiry grass, or a forest of stunted trees.  The scenery
resembled that of the high sandstone platform of the Blue Mountains;
the Casuarina (a tree somewhat resembling a Scotch fir) is, however,
here in greater number, and the Eucalyptus in rather less.  In the open
parts there were many grass-trees,--a plant which, in appearance, has
some affinity with the palm; but, instead of being surmounted by a
crown of noble fronds, it can boast merely of a tuft of very coarse
grass-like leaves.  The general bright green colour of the brushwood
and other plants, viewed from a distance, seemed to promise fertility.
A single walk, however, was enough to dispel such an illusion; and he
who thinks with me will never wish to walk again in so uninviting a
country.

One day I accompanied Captain Fitz Roy to Bald Head; the place
mentioned by so many navigators, where some imagined that they saw
corals, and others that they saw petrified trees, standing in the
position in which they had grown. According to our view, the beds have
been formed by the wind having heaped up fine sand, composed of minute
rounded particles of shells and corals, during which process branches
and roots of trees, together with many land-shells, became enclosed.
The whole then became consolidated by the percolation of calcareous
matter; and the cylindrical cavities left by the decaying of the wood,
were thus also filled up with a hard pseudo-stalactical stone.  The
weather is now wearing away the softer parts, and in consequence the
hard casts of the roots and branches of the trees project above the
surface, and, in a singularly deceptive manner, resemble the stumps of
a dead thicket.

A large tribe of natives, called the White Cockatoo men happened to pay
the settlement a visit while we were there. These men, as well as those
of the tribe belonging to King George's Sound, being tempted by the
offer of some tubs of rice and sugar, were persuaded to hold a
"corrobery," or great dancing-party.  As soon as it grew dark, small
fires were lighted, and the men commenced their toilet, which consisted
in painting themselves white in spots and lines. As soon as all was
ready, large fires were kept blazing, round which the women and
children were collected as spectators; the Cockatoo and King George's
men formed two distinct parties, and generally danced in answer to each
other. The dancing consisted in their running either sideways or in
Indian file into an open space, and stamping the ground with great
force as they marched together.  Their heavy footsteps were accompanied
by a kind of grunt, by beating their clubs and spears together, and by
various other gesticulations, such as extending their arms and
wriggling their bodies.  It was a most rude, barbarous scene, and, to
our ideas, without any sort of meaning; but we observed that the black
women and children watched it with the greatest pleasure.  Perhaps
these dances originally represented actions, such as wars and
victories; there was one called the Emu dance, in which each man
extended his arm in a bent manner, like the neck of that bird.  In
another dance, one man imitated the movements of a kangaroo grazing in
the woods, whilst a second crawled up, and pretended to spear him. When
both tribes mingled in the dance, the ground trembled with the
heaviness of their steps, and the air resounded with their wild cries.
Every one appeared in high spirits, and the group of nearly naked
figures, viewed by the light of the blazing fires, all moving in
hideous harmony, formed a perfect display of a festival amongst the
lowest barbarians.  In Tierra del Fuego, we have beheld many curious
scenes in savage life, but never, I think, one where the natives were
in such high spirits, and so perfectly at their ease.  After the
dancing was over, the whole party formed a great circle on the ground,
and the boiled rice and sugar was distributed, to the delight of all.

After several tedious delays from clouded weather, on the 14th of
March, we gladly stood out of King George's Sound on our course to
Keeling Island.  Farewell, Australia! you are a rising child, and
doubtless some day will reign a great princess in the South: but you
are too great and ambitious for affection, yet not great enough for
respect.  I leave your shores without sorrow or regret.

[1] It is remarkable how the same disease is modified in different
climates.  At the little island of St. Helena the introduction of
scarlet fever is dreaded as a plague.  In some countries, foreigners
and natives are as differently affected by certain contagious disorders
as if they had been different animals; of which fact some instances
have occurred in Chile; and, according to Humboldt, in Mexico (Polit.
Essay, New Spain, vol. iv.).

[2] Narrative of Missionary Enterprise, p. 282.

[3] Captain Beechey (chap. iv., vol. i.) states that the inhabitants of
Pitcairn Island are firmly convinced that after the arrival of every
ship they suffer cutaneous and other disorders.  Captain Beechey
attributes this to the change of diet during the time of the visit. Dr.
Macculloch (Western Isles, vol. ii. p. 32) says: "It is asserted, that
on the arrival of a stranger (at St. Kilda) all the inhabitants, in the
common phraseology, catch a cold." Dr. Macculloch considers the whole
case, although often previously affirmed, as ludicrous.  He adds,
however, that "the question was put by us to the inhabitants who
unanimously agreed in the story." In Vancouver's Voyage, there is a
somewhat similar statement with respect to Otaheite.  Dr. Dieffenbach,
in a note to his translation of the Journal, states that the same fact
is universally believed by the inhabitants of the Chatham Islands, and
in parts of New Zealand.  It is impossible that such a belief should
have become universal in the northern hemisphere, at the Antipodes, and
in the Pacific, without some good foundation.  Humboldt (Polit. Essay
on King of New Spain, vol. iv.) says, that the great epidemics of
Panama and Callao are "marked" by the arrival of ships from Chile,
because the people from that temperate region, first experience the
fatal effects of the torrid zones.  I may add, that I have heard it
stated in Shropshire, that sheep, which have been imported from
vessels, although themselves in a healthy condition, if placed in the
same fold with others, frequently produce sickness in the flock.

[4] Travels in Australia, vol. i. p. 154.  I must express my obligation
to Sir T. Mitchell, for several interesting personal communications on
the subject of these great valleys of New South Wales.

[5] I was interested by finding here the hollow conical pitfall of the
lion-ant, or some other insect; first a fly fell down the treacherous
slope and immediately disappeared; then came a large but unwary ant;
its struggles to escape being very violent, those curious little jets
of sand, described by Kirby and Spence (Entomol., vol. i. p. 425) as
being flirted by the insect's tail, were promptly directed against the
expected victim.  But the ant enjoyed a better fate than the fly, and
escaped the fatal jaws which lay concealed at the base of the conical
hollow.  This Australian pitfall was only about half the size of that
made by the European lion-ant.

[6] Physical Description of New South Wales and Van Diemen's Land, p.
354.



CHAPTER XX

KEELING ISLAND:--CORAL FORMATIONS

Keeling Island--Singular appearance--Scanty Flora--Transport of
Seeds--Birds and Insects--Ebbing and flowing Springs--Fields of dead
Coral--Stones transported in the roots of Trees--Great Crab--Stinging
Corals--Coral eating Fish--Coral Formations--Lagoon Islands, or
Atolls--Depth at which reef-building Corals can live--Vast Areas
interspersed with low Coral Islands--Subsidence of their
foundations--Barrier Reefs--Fringing Reefs--Conversion of Fringing
Reefs into Barrier Reefs, and into Atolls--Evidence of changes in
Level--Breaches in Barrier Reefs--Maldiva Atolls, their peculiar
structure--Dead and submerged Reefs--Areas of subsidence and
elevation--Distribution of Volcanoes--Subsidence slow, and vast in
amount.


APRIL 1st.--We arrived in view of the Keeling or Cocos Islands,
situated in the Indian Ocean, and about six hundred miles distant from
the coast of Sumatra.  This is one of the lagoon-islands (or atolls) of
coral formation, similar to those in the Low Archipelago which we
passed near.  When the ship was in the channel at the entrance, Mr.
Liesk, an English resident, came off in his boat.  The history of the
inhabitants of this place, in as few words as possible, is as follows.
About nine years ago, Mr. Hare, a worthless character, brought from the
East Indian archipelago a number of Malay slaves, which now including
children, amount to more than a hundred.  Shortly afterwards, Captain
Ross, who had before visited these islands in his merchant-ship,
arrived from England, bringing with him his family and goods for
settlement: along with him came Mr. Liesk, who had been a mate in his
vessel. The Malay slaves soon ran away from the islet on which Mr. Hare
was settled, and joined Captain Ross's party.  Mr. Hare upon this was
ultimately obliged to leave the place.

The Malays are now nominally in a state of freedom, and certainly are
so, as far as regards their personal treatment; but in most other
points they are considered as slaves.  From their discontented state,
from the repeated removals from islet to islet, and perhaps also from a
little mismanagement, things are not very prosperous.  The island has
no domestic quadruped, excepting the pig, and the main vegetable
production is the cocoa-nut.  The whole prosperity of the place depends
on this tree: the only exports being oil from the nut, and the nuts
themselves, which are taken to Singapore and Mauritius, where they are
chiefly used, when grated, in making curries.  On the cocoa-nut, also,
the pigs, which are loaded with fat, almost entirely subsist, as do the
ducks and poultry.  Even a huge land-crab is furnished by nature with
the means to open and feed on this most useful production.

The ring-formed reef of the lagoon-island is surmounted in the greater
part of its length by linear islets.  On the northern or leeward side,
there is an opening through which vessels can pass to the anchorage
within.  On entering, the scene was very curious and rather pretty; its
beauty, however, entirely depended on the brilliancy of the surrounding
colours.  The shallow, clear, and still water of the lagoon, resting in
its greater part on white sand, is, when illumined by a vertical sun,
of the most vivid green.  This brilliant expanse, several miles in
width, is on all sides divided, either by a line of snow-white breakers
from the dark heaving waters of the ocean, or from the blue vault of
heaven by the strips of land, crowned by the level tops of the
cocoa-nut trees.  As a white cloud here and there affords a pleasing
contrast with the azure sky, so in the lagoon, bands of living coral
darken the emerald green water.

The next morning after anchoring, I went on shore on Direction Island.
The strip of dry land is only a few hundred yards in width; on the
lagoon side there is a white calcareous beach, the radiation from which
under this sultry climate was very oppressive; and on the outer coast,
a solid broad flat of coral-rock served to break the violence of the
open sea.  Excepting near the lagoon, where there is some sand, the
land is entirely composed of rounded fragments of coral.  In such a
loose, dry, stony soil, the climate of the intertropical regions alone
could produce a vigorous vegetation. On some of the smaller islets,
nothing could be more elegant than the manner in which the young and
full-grown cocoa-nut trees, without destroying each other's symmetry,
were mingled into one wood.  A beach of glittering white sand formed a
border to these fairy spots.

I will now give a sketch of the natural history of these islands,
which, from its very paucity, possesses a peculiar interest.  The
cocoa-nut tree, at first glance, seems to compose the whole wood; there
are however, five or six other trees.  One of these grows to a very
large size, but from the extremes of softness of its wood, is useless;
another sort affords excellent timber for ship-building.  Besides the
trees, the number of plants is exceedingly limited, and consists of
insignificant weeds.  In my collection, which includes, I believe,
nearly the perfect Flora, there are twenty species, without reckoning a
moss, lichen, and fungus.  To this number two trees must be added; one
of which was not in flower, and the other I only heard of.  The latter
is a solitary tree of its kind, and grows near the beach, where,
without doubt, the one seed was thrown up by the waves.  A Guilandina
also grows on only one of the islets.  I do not include in the above
list the sugar-cane, banana, some other vegetables, fruit-trees, and
imported grasses.  As the islands consist entirely of coral, and at one
time must have existed as mere water-washed reefs, all their
terrestrial productions must have been transported here by the waves of
the sea. In accordance with this, the Florula has quite the character
of a refuge for the destitute: Professor Henslow informs me that of the
twenty species nineteen belong to different genera, and these again to
no less than sixteen families! [1]

In Holman's [2] Travels an account is given, on the authority of Mr. A.
S. Keating, who resided twelve months on these islands, of the various
seeds and other bodies which have been known to have been washed on
shore.  "Seeds and plants from Sumatra and Java have been driven up by
the surf on the windward side of the islands.  Among them have been
found the Kimiri, native of Sumatra and the peninsula of Malacca; the
cocoa-nut of Balci, known by its shape and size; the Dadass, which is
planted by the Malays with the pepper-vine, the latter intwining round
its trunk, and supporting itself by the prickles on its stem; the
soap-tree; the castor-oil plant; trunks of the sago palm; and various
kinds of seeds unknown to the Malays settled on the islands. These are
all supposed to have been driven by the N. W. monsoon to the coast of
New Holland, and thence to these islands by the S. E. trade-wind. Large
masses of Java teak and Yellow wood have also been found, besides
immense trees of red and white cedar, and the blue gumwood of New
Holland, in a perfectly sound condition.  All the hardy seeds, such as
creepers, retain their germinating power, but the softer kinds, among
which is the mangostin, are destroyed in the passage.  Fishing-canoes,
apparently from Java, have at times been washed on shore." It is
interesting thus to discover how numerous the seeds are, which, coming
from several countries, are drifted over the wide ocean.  Professor
Henslow tells me, he believes that nearly all the plants which I
brought from these islands, are common littoral species in the East
Indian archipelago.  From the direction, however, of the winds and
currents, it seems scarcely possible that they could have come here in
a direct line.  If, as suggested with much probability by Mr. Keating,
they were first carried towards the coast of New Holland, and thence
drifted back together with the productions of that country, the seeds,
before germinating, must have travelled between 1800 and 2400 miles.

Chamisso, [3] when describing the Radack Archipelago, situated in the
western part of the Pacific, states that "the sea brings to these
islands the seeds and fruits of many trees, most of which have yet not
grown here.  The greater part of these seeds appear to have not yet
lost the capability of growing."

It is also said that palms and bamboos from somewhere in the torrid
zone, and trunks of northern firs, are washed on shore: these firs must
have come from an immense distance.  These facts are highly
interesting.  It cannot be doubted that if there were land-birds to
pick up the seeds when first cast on shore, and a soil better adapted
for their growth than the loose blocks of coral, that the most isolated
of the lagoon-islands would in time possess a far more abundant Flora
than they now have.

The list of land animals is even poorer than that of the plants.  Some
of the islets are inhabited by rats, which were brought in a ship from
the Mauritius, wrecked here.  These rats are considered by Mr.
Waterhouse as identical with the English kind, but they are smaller,
and more brightly coloured. There are no true land-birds, for a snipe
and a rail (Rallus Phillippensis), though living entirely in the dry
herbage, belong to the order of Waders.  Birds of this order are said
to occur on several of the small low islands in the Pacific.  At
Ascension, where there is no land-bird, a rail (Porphyrio simplex) was
shot near the summit of the mountain, and it was evidently a solitary
straggler.  At Tristan d'Acunha, where, according to Carmichael, there
are only two land-birds, there is a coot.  From these facts I believe
that the waders, after the innumerable web-footed species, are
generally the first colonists of small isolated islands.  I may add,
that whenever I noticed birds, not of oceanic species, very far out at
sea, they always belonged to this order; and hence they would naturally
become the earliest colonists of any remote point of land.

Of reptiles I saw only one small lizard.  Of insects I took pains to
collect every kind.  Exclusive of spiders, which were numerous, there
were thirteen species. [4] Of these, one only was a beetle.  A small
ant swarmed by thousands under the loose dry blocks of coral, and was
the only true insect which was abundant.  Although the productions of
the land are thus scanty, if we look to the waters of the surrounding
sea, the number of organic beings is indeed infinite.  Chamisso has
described [5] the natural history of a lagoon-island in the Radack
Archipelago; and it is remarkable how closely its inhabitants, in
number and kind, resemble those of Keeling Island.  There is one lizard
and two waders, namely, a snipe and curlew.  Of plants there are
nineteen species, including a fern; and some of these are the same with
those growing here, though on a spot so immensely remote, and in a
different ocean.

The long strips of land, forming the linear islets, have been raised
only to that height to which the surf can throw fragments of coral, and
the wind heap up calcareous sand. The solid flat of coral rock on the
outside, by its breadth, breaks the first violence of the waves, which
otherwise, in a day, would sweep away these islets and all their
productions. The ocean and the land seem here struggling for mastery:
although terra firma has obtained a footing, the denizens of the water
think their claim at least equally good.  In every part one meets
hermit crabs of more than one species, [6] carrying on their backs the
shells which they have stolen from the neighbouring beach.  Overhead,
numerous gannets, frigate-birds, and terns, rest on the trees; and the
wood, from the many nests and from the smell of the atmosphere, might
be called a sea-rookery.  The gannets, sitting on their rude nests,
gaze at one with a stupid yet angry air.  The noddies, as their name
expresses, are silly little creatures.  But there is one charming bird:
it is a small, snow-white tern, which smoothly hovers at the distance
of a few feet above one's head, its large black eye scanning, with
quiet curiosity, your expression.  Little imagination is required to
fancy that so light and delicate a body must be tenanted by some
wandering fairy spirit.

Sunday, April 3rd.--After service I accompanied Captain Fitz Roy to the
settlement, situated at the distance of some miles, on the point of an
islet thickly covered with tall cocoa-nut trees.  Captain Ross and Mr.
Liesk live in a large barn-like house open at both ends, and lined with
mats made of woven bark.  The houses of the Malays are arranged along
the shore of the lagoon.  The whole place had rather a desolate aspect,
for there were no gardens to show the signs of care and cultivation.
The natives belong to different islands in the East Indian archipelago,
but all speak the same language: we saw the inhabitants of Borneo,
Celebes, Java, and Sumatra.  In colour they resemble the Tahitians,
from whom they do not widely differ in features.  Some of the women,
however, show a good deal of the Chinese character.  I liked both their
general expressions and the sound of their voices. They appeared poor,
and their houses were destitute of furniture; but it was evident, from
the plumpness of the little children, that cocoa-nuts and turtle afford
no bad sustenance.

On this island the wells are situated, from which ships obtain water.
At first sight it appears not a little remarkable that the fresh water
should regularly ebb and flow with the tides; and it has even been
imagined, that sand has the power of filtering the salt from the
sea-water.  These ebbing wells are common on some of the low islands in
the West Indies. The compressed sand, or porous coral rock, is
permeated like a sponge with the salt water, but the rain which falls
on the surface must sink to the level of the surrounding sea, and must
accumulate there, displacing an equal bulk of the salt water.  As the
water in the lower part of the great sponge-like coral mass rises and
falls with the tides, so will the water near the surface; and this will
keep fresh, if the mass be sufficiently compact to prevent much
mechanical admixture; but where the land consists of great loose blocks
of coral with open interstices, if a well be dug, the water, as I have
seen, is brackish.

After dinner we stayed to see a curious half superstitious scene acted
by the Malay women.  A large wooden spoon dressed in garments, and
which had been carried to the grave of a dead man, they pretend becomes
inspired at the full of the moon, and will dance and jump about.  After
the proper preparations, the spoon, held by two women, became
convulsed, and danced in good time to the song of the surrounding
children and women.  It was a most foolish spectacle; but Mr. Liesk
maintained that many of the Malays believed in its spiritual movements.
The dance did not commence till the moon had risen, and it was well
worth remaining to behold her bright orb so quietly shining through the
long arms of the cocoa-nut trees as they waved in the evening breeze.
These scenes of the tropics are in themselves so delicious, that they
almost equal those dearer ones at home, to which we are bound by each
best feeling of the mind.

The next day I employed myself in examining the very interesting, yet
simple structure and origin of these islands. The water being unusually
smooth, I waded over the outer flat of dead rock as far as the living
mounds of coral, on which the swell of the open sea breaks.  In some of
the gullies and hollows there were beautiful green and other coloured
fishes, and the form and tints of many of the zoophytes were admirable.
It is excusable to grow enthusiastic over the infinite numbers of
organic beings with which the sea of the tropics, so prodigal of life,
teems; yet I must confess I think those naturalists who have described,
in well-known words, the submarine grottoes decked with a thousand
beauties, have indulged in rather exuberant language.

April 6th.--I accompanied Captain Fitz Roy to an island at the head of
the lagoon: the channel was exceedingly intricate, winding through
fields of delicately branched corals. We saw several turtle and two
boats were then employed in catching them.  The water was so clear and
shallow, that although at first a turtle quickly dives out of sight,
yet in a canoe or boat under sail, the pursuers after no very long
chase come up to it.  A man standing ready in the bow, at this moment
dashes through the water upon the turtle's back; then clinging with
both hands by the shell of its neck, he is carried away till the animal
becomes exhausted and is secured. It was quite an interesting chase to
see the two boats thus doubling about, and the men dashing head
foremost into the water trying to seize their prey.  Captain Moresby
informs me that in the Chagos archipelago in this same ocean, the
natives, by a horrible process, take the shell from the back of the
living turtle.  "It is covered with burning charcoal, which causes the
outer shell to curl upwards, it is then forced off with a knife, and
before it becomes cold flattened between boards.  After this barbarous
process the animal is suffered to regain its native element, where,
after a certain time, a new shell is formed; it is, however, too thin
to be of any service, and the animal always appears languishing and
sickly."

When we arrived at the head of the lagoon, we crossed a narrow islet,
and found a great surf breaking on the windward coast.  I can hardly
explain the reason, but there is to my mind much grandeur in the view
of the outer shores of these lagoon-islands.  There is a simplicity in
the barrier-like beach, the margin of green bushes and tall cocoa-nuts,
the solid flat of dead coral-rock, strewed here and there with great
loose fragments, and the line of furious breakers, all rounding away
towards either hand.  The ocean throwing its waters over the broad reef
appears an invincible, all-powerful enemy; yet we see it resisted, and
even conquered, by means which at first seem most weak and inefficient.
It is not that the ocean spares the rock of coral; the great fragments
scattered over the reef, and heaped on the beach, whence the tall
cocoa-nut springs, plainly bespeak the unrelenting power of the waves.
Nor are any periods of repose granted.  The long swell caused by the
gentle but steady action of the trade-wind, always blowing in one
direction over a wide area, causes breakers, almost equalling in force
those during a gale of wind in the temperate regions, and which never
cease to rage.  It is impossible to behold these waves without feeling
a conviction that an island, though built of the hardest rock, let it
be porphyry, granite, or quartz, would ultimately yield and be
demolished by such an irresistible power.  Yet these low, insignificant
coral-islets stand and are victorious: for here another power, as an
antagonist, takes part in the contest.  The organic forces separate the
atoms of carbonate of lime, one by one, from the foaming breakers, and
unite them into a symmetrical structure.  Let the hurricane tear up its
thousand huge fragments; yet what will that tell against the
accumulated labour of myriads of architects at work night and day,
month after month?  Thus do we see the soft and gelatinous body of a
polypus, through the agency of the vital laws, conquering the great
mechanical power of the waves of an ocean which neither the art of man
nor the inanimate works of nature could successfully resist.

We did not return on board till late in the evening, for we stayed a
long time in the lagoon, examining the fields of coral and the gigantic
shells of the chama, into which, if a man were to put his hand, he
would not, as long as the animal lived, be able to withdraw it.  Near
the head of the lagoon I was much surprised to find a wide area,
considerably more than a mile square, covered with a forest of
delicately branching corals, which, though standing upright, were all
dead and rotten.  At first I was quite at a loss to understand the
cause afterwards it occurred to me that it was owing to the following
rather curious combination of circumstances.  It should, however, first
be stated, that corals are not able to survive even a short exposure in
the air to the sun's rays, so that their upward limit of growth is
determined by that of lowest water at spring tides.  It appears, from
some old charts, that the long island to windward was formerly
separated by wide channels into several islets; this fact is likewise
indicated by the trees being younger on these portions.  Under the
former condition of the reef, a strong breeze, by throwing more water
over the barrier, would tend to raise the level of the lagoon.  Now it
acts in a directly contrary manner; for the water within the lagoon not
only is not increased by currents from the outside, but is itself blown
outwards by the force of the wind.  Hence it is observed, that the tide
near the head of the lagoon does not rise so high during a strong
breeze as it does when it is calm.  This difference of level, although
no doubt very small, has, I believe, caused the death of those
coral-groves, which under the former and more open condition of the
outer reef has attained the utmost possible limit of upward growth.

A few miles north of Keeling there is another small atoll, the lagoon
of which is nearly filled up with coral-mud.  Captain Ross found
embedded in the conglomerate on the outer coast, a well-rounded
fragment of greenstone, rather larger than a man's head: he and the men
with him were so much surprised at this, that they brought it away and
preserved it as a curiosity.  The occurrence of this one stone, where
every other particle of matter is calcareous, certainly is very
puzzling.  The island has scarcely ever been visited, nor is it
probable that a ship had been wrecked there.  From the absence of any
better explanation, I came to the conclusion that it must have come
entangled in the roots of some large tree: when, however, I considered
the great distance from the nearest land, the combination of chances
against a stone thus being entangled, the tree washed into the sea,
floated so far, then landed safely, and the stone finally so embedded
as to allow of its discovery, I was almost afraid of imagining a means
of transport apparently so improbable.  It was therefore with great
interest that I found Chamisso, the justly distinguished naturalist who
accompanied Kotzebue, stating that the inhabitants of the Radack
archipelago, a group of lagoon-islands in the midst of the Pacific,
obtained stones for sharpening their instruments by searching the roots
of trees which are cast upon the beach.  It will be evident that this
must have happened several times, since laws have been established that
such stones belong to the chief, and a punishment is inflicted on any
one who attempts to steal them. When the isolated position of these
small islands in the midst of a vast ocean--their great distance from
any land excepting that of coral formation, attested by the value which
the inhabitants, who are such bold navigators, attach to a stone of any
kind, [7]--and the slowness of the currents of the open sea, are all
considered, the occurrence of pebbles thus transported does appear
wonderful.  Stones may often be thus carried; and if the island on
which they are stranded is constructed of any other substance besides
coral, they would scarcely attract attention, and their origin at least
would never be guessed.  Moreover, this agency may long escape
discovery from the probability of trees, especially those loaded with
stones, floating beneath the surface.  In the channels of Tierra del
Fuego large quantities of drift timber are cast upon the beach, yet it
is extremely rare to meet a tree swimming on the water.  These facts
may possibly throw light on single stones, whether angular or rounded,
occasionally found embedded in fine sedimentary masses.

During another day I visited West Islet, on which the vegetation was
perhaps more luxuriant than on any other. The cocoa-nut trees generally
grow separate, but here the young ones flourished beneath their tall
parents, and formed with their long and curved fronds the most shady
arbours. Those alone who have tried it, know how delicious it is to be
seated in such shade, and drink the cool pleasant fluid of the
cocoa-nut.  In this island there is a large bay-like space, composed of
the finest white sand: it is quite level and is only covered by the
tide at high water; from this large bay smaller creeks penetrate the
surrounding woods. To see a field of glittering white sand,
representing water, with the cocoa-nut trees extending their tall and
waving trunks around the margin, formed a singular and very pretty view.

I have before alluded to a crab which lives on the cocoa-nuts; it is
very common on all parts of the dry land, and grows to a monstrous
size: it is closely allied or identical with the Birgos latro.  The
front pair of legs terminate in very strong and heavy pincers, and the
last pair are fitted with others weaker and much narrower.  It would at
first be thought quite impossible for a crab to open a strong cocoa-nut
covered with the husk; but Mr. Liesk assures me that he has repeatedly
seen this effected.  The crab begins by tearing the husk, fibre by
fibre, and always from that end under which the three eye-holes are
situated; when this is completed, the crab commences hammering with its
heavy claws on one of the eye-holes till an opening is made.  Then
turning round its body, by the aid of its posterior and narrow pair of
pincers, it extracts the white albuminous substance. I think this is as
curious a case of instinct as ever I heard of, and likewise of
adaptation in structure between two objects apparently so remote from
each other in the scheme of nature, as a crab and a cocoa-nut tree. The
Birgos is diurnal in its habits; but every night it is said to pay a
visit to the sea, no doubt for the purpose of moistening its branchiae.
The young are likewise hatched, and live for some time, on the coast.
These crabs inhabit deep burrows, which they hollow out beneath the
roots of trees; and where they accumulate surprising quantities of the
picked fibres of the cocoa-nut husk, on which they rest as on a bed.
The Malays sometimes take advantage of this, and collect the fibrous
mass to use as junk.  These crabs are very good to eat; moreover, under
the tail of the larger ones there is a mass of fat, which, when melted,
sometimes yields as much as a quart bottle full of limpid oil.  It has
been stated by some authors that the Birgos crawls up the cocoa-nut
trees for the purpose of stealing the nuts: I very much doubt the
possibility of this; but with the Pandanus [8] the task would be very
much easier.  I was told by Mr. Liesk that on these islands the Birgos
lives only on the nuts which have fallen to the ground.

Captain Moresby informs me that this crab inhabits the Chagos and
Seychelle groups, but not the neighbouring Maldiva archipelago.  It
formerly abounded at Mauritius, but only a few small ones are now found
there.  In the Pacific, this species, or one with closely allied
habits, is said [9] to inhabit a single coral island, north of the
Society group.  To show the wonderful strength of the front pair of
pincers, I may mention, that Captain Moresby confined one in a strong
tin-box, which had held biscuits, the lid being secured with wire; but
the crab turned down the edges and escaped.  In turning down the edges,
it actually punched many small holes quite through the tin!

I was a good deal surprised by finding two species of coral of the
genus Millepora (M. complanata and alcicornis), possessed of the power
of stinging.  The stony branches or plates, when taken fresh from the
water, have a harsh feel and are not slimy, although possessing a
strong and disagreeable smell.  The stinging property seems to vary in
different specimens: when a piece was pressed or rubbed on the tender
skin of the face or arm, a pricking sensation was usually caused, which
came on after the interval of a second, and lasted only for a few
minutes.  One day, however, by merely touching my face with one of the
branches, pain was instantaneously caused; it increased as usual after
a few seconds, and remaining sharp for some minutes, was perceptible
for half an hour afterwards.  The sensation was as bad as that from a
nettle, but more like that caused by the Physalia or Portuguese
man-of-war.  Little red spots were produced on the tender skin of the
arm, which appeared as if they would have formed watery pustules, but
did not.  M. Quoy mentions this case of the Millepora; and I have heard
of stinging corals in the West Indies.  Many marine animals seem to
have this power of stinging: besides the Portuguese man-of-war, many
jelly-fish, and the Aplysia or sea-slug of the Cape de Verd Islands, it
is stated in the voyage of the Astrolabe, that an Actinia or
sea-anemone, as well as a flexible coralline allied to Sertularia, both
possess this means of offence or defence.  In the East Indian sea, a
stinging sea-weed is said to be found.

Two species of fish, of the genus Scarus, which are common here,
exclusively feed on coral: both are coloured of a splendid
bluish-green, one living invariably in the lagoon, and the other
amongst the outer breakers.  Mr. Liesk assured us, that he had
repeatedly seen whole shoals grazing with their strong bony jaws on the
tops of the coral branches: I opened the intestines of several, and
found them distended with yellowish calcareous sandy mud.  The slimy
disgusting Holuthuriae (allied to our star-fish), which the Chinese
gourmands are so fond of, also feed largely, as I am informed by Dr.
Allan, on corals; and the bony apparatus within their bodies seems well
adapted for this end.  These Holuthuriae, the fish, the numerous
burrowing shells, and nereidous worms, which perforate every block of
dead coral, must be very efficient agents in producing the fine white
mud which lies at the bottom and on the shores of the lagoon.  A
portion, however, of this mud, which when wet resembled pounded chalk,
was found by Professor Ehrenberg to be partly composed of
siliceous-shielded infusoria.

April 12th.--In the morning we stood out of the lagoon on our passage
to the Isle of France.  I am glad we have visited these islands: such
formations surely rank high amongst the wonderful objects of this
world.  Captain Fitz Roy found no bottom with a line 7200 feet in
length, at the distance of only 2200 yards from the shore; hence this
island forms a lofty submarine mountain, with sides steeper even than
those of the most abrupt volcanic cone.  The saucer-shaped summit is
nearly ten miles across; and every single atom, [10] from the least
particle to the largest fragment of rock, in this great pile, which
however is small compared with very many other lagoon-islands, bears
the stamp of having been subjected to organic arrangement.  We feel
surprise when travellers tell us of the vast dimensions of the Pyramids
and other great ruins, but how utterly insignificant are the greatest
of these, when compared to these mountains of stone accumulated by the
agency of various minute and tender animals!  This is a wonder which
does not at first strike the eye of the body, but, after reflection,
the eye of reason.

I will now give a very brief account of the three great classes of
coral-reefs; namely, Atolls, Barrier, and Fringing-reefs, and will
explain my views [11] on their formation.  Almost every voyager who has
crossed the Pacific has expressed his unbounded astonishment at the
lagoon-islands, or as I shall for the future call them by their Indian
name of atolls, and has attempted some explanation.  Even as long ago
as the year 1605, Pyrard de Laval well exclaimed, "C'est

[picture]

une merveille de voir chacun de ces atollons, environne d'un grand banc
de pierre tout autour, n'y ayant point d'artifice humain." The
accompanying sketch of Whitsunday Island in the Pacific, copied from,
Capt. Beechey's admirable Voyage, gives but a faint idea of the
singular aspect of an atoll: it is one of the smallest size, and has
its narrow islets united together in a ring.  The immensity of the
ocean, the fury of the breakers, contrasted with the lowness of the
land and the smoothness of the bright green water within the lagoon,
can hardly be imagined without having been seen.

The earlier voyagers fancied that the coral-building animals
instinctively built up their great circles to afford themselves
protection in the inner parts; but so far is this from the truth, that
those massive kinds, to whose growth on the exposed outer shores the
very existence of the reef depends, cannot live within the lagoon,
where other delicately-branching kinds flourish.  Moreover, on this
view, many species of distinct genera and families are supposed to
combine for one end; and of such a combination, not a single instance
can be found in the whole of nature.  The theory that has been most
generally received is, that atolls are based on submarine craters; but
when we consider the form and size of some, the number, proximity, and
relative positions of others, this idea loses its plausible character:
thus Suadiva atoll is 44 geographical miles in diameter in one line, by
34 miles in another line; Rimsky is 54 by 20 miles across, and it has a
strangely sinuous margin; Bow atoll is 30 miles long, and on an average
only 6 in width; Menchicoff atoll consists of three atolls united or
tied together.  This theory, moreover, is totally inapplicable to the
northern Maldiva atolls in the Indian Ocean (one of which is 88 miles
in length, and between 10 and 20 in breadth), for they are not bounded
like ordinary atolls by narrow reefs, but by a vast number of separate
little atolls; other little atolls rising out of the great central
lagoon-like spaces.  A third and better theory was advanced by
Chamisso, who thought that from the corals growing more vigorously
where exposed to the open sea, as undoubtedly is the case, the outer
edges would grow up from the general foundation before any other part,
and that this would account for the ring or cup-shaped structure.  But
we shall immediately see, that in this, as well as in the
crater-theory, a most important consideration has been overlooked,
namely, on what have the reef-building corals, which cannot live at a
great depth, based their massive structures?

Numerous soundings were carefully taken by Captain Fitz Roy on the
steep outside of Keeling atoll, and it was found that within ten
fathoms, the prepared tallow at the bottom of the lead, invariably came
up marked with the impression of living corals, but as perfectly clean
as if it had been dropped on a carpet of turf; as the depth increased,
the impressions became less numerous, but the adhering particles of
sand more and more numerous, until at last it was evident that the
bottom consisted of a smooth sandy layer: to carry on the analogy of
the turf, the blades of grass grew thinner and thinner, till at last
the soil was so sterile, that nothing sprang from it.  From these
observations, confirmed by many others, it may be safely inferred that
the utmost depth at which corals can construct reefs is between 20 and
30 fathoms. Now there are enormous areas in the Pacific and Indian
Ocean, in which every single island is of coral formation, and is
raised only to that height to which the waves can throw up fragments,
and the winds pile up sand.  Thus Radack group of atolls is an
irregular square, 520 miles long and 240 broad; the Low Archipelago is
elliptic-formed, 840 miles in its longer, and 420 in its shorter axis:
there are other small groups and single low islands between these two
archipelagoes, making a linear space of ocean actually more than 4000
miles in length, in which not one single island rises above the
specified height.  Again, in the Indian Ocean there is a space of ocean
1500 miles in length, including three archipelagoes, in which every
island is low and of coral formation.  From the fact of the
reef-building corals not living at great depths, it is absolutely
certain that throughout these vast areas, wherever there is now an
atoll, a foundation must have originally existed within a depth of from
20 to 30 fathoms from the surface.  It is improbable in the highest
degree that broad, lofty, isolated, steep-sided banks of sediment,
arranged in groups and lines hundreds of leagues in length, could have
been deposited in the central and profoundest parts of the Pacific and
Indian Oceans, at an immense distance from any continent, and where the
water is perfectly limpid.  It is equally improbable that the elevatory
forces should have uplifted throughout the above vast areas,
innumerable great rocky banks within 20 to 30 fathoms, or 120 to 180
feet, of the surface of the sea, and not one single point above that
level; for where on the whole surface of the globe can we find a single
chain of mountains, even a few hundred miles in length, with their many
summits rising within a few feet of a given level, and not one pinnacle
above it?  If then the foundations, whence the atoll-building corals
sprang, were not formed of sediment, and if they were not lifted up to
the required level, they must of necessity have subsided into it; and
this at once solves the difficulty.  For as mountain after mountain,
and island after island, slowly sank beneath the water, fresh bases
would be successively afforded for the growth of the corals.  It is
impossible here to enter into all the necessary details, but I venture
to defy [12] any one to explain in any other manner how it is possible
that numerous islands should be distributed throughout vast areas--all
the islands being low--all being built of corals, absolutely requiring
a foundation within a limited depth from the surface.

Before explaining how atoll-formed reefs acquire their peculiar
structure, we must turn to the second great class, namely,
Barrier-reefs.  These either extend in straight lines in front of the
shores of a continent or of a large island, or they encircle smaller
islands; in both cases, being separated from the land by a broad and
rather deep channel of water, analogous to the lagoon within an atoll.
It is remarkable how little attention has been paid to encircling
barrier-reefs; yet they are truly wonderful structures.  The following
sketch represents part of the barrier encircling the island of Bolabola
in the Pacific, as seen from one of the central peaks. In this instance
the whole line of reef has been converted into land; but usually a
snow-white line of great breakers, with only here and there a single
low islet crowned with cocoa-nut trees, divides the dark heaving waters
of the ocean from the light-green expanse of the lagoon-channel.  And
the quiet waters of this channel generally bathe a fringe of low
alluvial soil, loaded with the most beautiful productions of the
tropics, and lying at the foot of the wild, abrupt, central mountains.

Encircling barrier-reefs are of all sizes, from three miles to no less
than forty-four miles in diameter; and that which fronts one side, and
encircles both ends, of New Caledonia, is 400 miles long.  Each reef
includes one, two, or several rocky islands of various heights; and in
one instance, even as many as twelve separate islands.  The reef runs
at a greater or less distance from the included land; in the Society
archipelago generally from one to three or four miles; but at Hogoleu
the reef is 20 miles on the southern side, and 14 miles on the opposite
or northern side, from the included islands.  The depth within the
lagoon-channel also varies much; from 10 to 30 fathoms may be taken as
an average; but at Vanikoro there are spaces no less than 56 fathoms or
363 feet deep.  Internally the reef either slopes gently into the
lagoon-channel, or ends in a perpendicular wall sometimes between two
and three hundred feet under water in height: externally the reef
rises, like an atoll, with extreme abruptness out of the profound
depths of the ocean.

What can be more singular than these structures?  We see

[picture]

an island, which may be compared to a castle situated on the summit of
a lofty submarine mountain, protected by a great wall of coral-rock,
always steep externally and sometimes internally, with a broad level
summit, here and there breached by a narrow gateway, through which the
largest ships can enter the wide and deep encircling moat.

As far as the actual reef of coral is concerned, there is not the
smallest difference, in general size, outline, grouping, and even in
quite trifling details of structure, between a barrier and an atoll.
The geographer Balbi has well remarked, that an encircled island is an
atoll with high land rising out of its lagoon; remove the land from
within, and a perfect atoll is left.

But what has caused these reefs to spring up at such great distances
from the shores of the included islands?  It cannot be that the corals
will not grow close to the land; for the shores within the
lagoon-channel, when not surrounded by alluvial soil, are often fringed
by living reefs; and we shall presently see that there is a whole
class, which I have called Fringing Reefs from their close attachment
to the shores both of continents and of islands.  Again, on what have
the reef-building corals, which cannot live at great depths, based
their encircling structures?  This is a great apparent difficulty,
analogous to that in the case of atolls, which has generally been
overlooked.  It will be perceived more clearly by inspecting the
following sections which are real ones, taken in north and south lines,
through the islands with their barrier-reefs, of Vanikoro, Gambier, and
Maurua; and they are laid down, both vertically and horizontally, on
the same scale of a quarter of an inch to a mile.

It should be observed that the sections might have been taken in any
direction through these islands, or through

[picture]

many other encircled islands, and the general features would have been
the same.  Now, bearing in mind that reef-building coral cannot live at
a greater depth than from 20 to 30 fathoms, and that the scale is so
small that the plummets on the right hand show a depth of  200 fathoms,
on what are these barrier-reefs based?  Are we to suppose that each
island is surrounded by a collar-like submarine ledge of rock, or by a
great bank of sediment, ending abruptly where the reef ends?

If the sea had formerly eaten deeply into the islands, before they were
protected by the reefs, thus having left a shallow ledge round them
under water, the present shores would have been invariably bounded by
great precipices, but this is most rarely the case.  Moreover, on this
notion, it is not possible to explain why the corals should have sprung
up, like a wall, from the extreme outer margin of the ledge, often
leaving a broad space of water within, too deep for the growth of
corals.  The accumulation of a wide bank of sediment all round these
islands, and generally widest where the included islands are smallest,
is highly improbable, considering their exposed positions in the
central and deepest parts of the ocean.  In the case of the
barrier-reef of New Caledonia, which extends for 150 miles beyond the
northern point of the islands, in the same straight line with which it
fronts the west coast, it is hardly possible to believe that a bank of
sediment could thus have been straightly deposited in front of a lofty
island, and so far beyond its termination in the open sea.  Finally, if
we look to other oceanic islands of about the same height and of
similar geological constitution, but not encircled by coral-reefs, we
may in vain search for so trifling a circumambient depth as 30 fathoms,
except quite near to their shores; for usually land that rises abruptly
out of water, as do most of the encircled and non-encircled oceanic
islands, plunges abruptly under it.  On what then, I repeat, are these
barrier reefs based?  Why, with their wide and deep moat-like channels,
do they stand so far from the included land?  We shall soon see how
easily these difficulties disappear.

We come now to our third class of Fringing-reefs, which will require a
very short notice.  Where the land slopes abruptly under water, these
reefs are only a few yards in width, forming a mere ribbon or fringe
round the shores: where the land slopes gently under the water the reef
extends further, sometimes even as much as a mile from the land; but in
such cases the soundings outside the reef always show that the
submarine prolongation of the land is gently inclined. In fact, the
reefs extend only to that distance from the shore, at which a
foundation within the requisite depth from 20 to 30 fathoms is found.
As far as the actual reef is concerned, there is no essential
difference between it and that forming a barrier or an atoll: it is,
however, generally of less width, and consequently few islets have been
formed on it.  From the corals growing more vigorously on the outside,
and from the noxious effect of the sediment washed inwards, the outer
edge of the reef is the highest part, and between it and the land there
is generally a shallow sandy channel a few feet in depth.  Where banks
or sediments have accumulated near to the surface, as in parts of the
West Indies, they sometimes become fringed with corals, and hence in
some degree resemble lagoon-islands or atolls, in the same manner as
fringing-reefs, surrounding gently sloping islands, in some degree
resemble barrier-reefs.


No theory on the formation of coral-reefs can be considered
satisfactory which does not include the three great

[picture]

classes.  We have seen that we are driven to believe in the subsidence
of those vast areas, interspersed with low islands, of which not one
rises above the height to which the wind and waves can throw up matter,
and yet are constructed by animals requiring a foundation, and that
foundation to lie at no great depth.  Let us then take an island
surrounded by fringing-reefs, which offer no difficulty in their
structure; and let this island with its reefs, represented by the
unbroken lines in the woodcut, slowly subside.  Now, as the island
sinks down, either a few feet at a time or quite insensibly, we may
safely infer, from what is known of the conditions favourable to the
growth of coral, that the living masses, bathed by the surf on the
margin of the reef, will soon regain the surface.  The water, however,
will encroach little by little on the shore, the island becoming lower
and smaller, and the space between the inner edge of the reef and the
beach proportionately broader.  A section of the reef and island in
this state, after a subsidence of several hundred feet, is given by the
dotted lines.  Coral islets are supposed to have been formed on the
reef; and a ship is anchored in the lagoon-channel.  This channel will
be more or less deep, according to the rate of subsidence, to the
amount of sediment accumulated in it, and to the growth of the
delicately branched corals which can live there.  The section in this
state resembles in every respect one drawn through an encircled island:
in fact, it is a real section (on the scale of .517 of an inch to a
mile) through Bolabola in the Pacific.  We can now at once see why
encircling barrier-reefs stand so far from the shores which they front.
We can also perceive, that a line drawn perpendicularly down from the
outer edge of the new reef, to the foundation of solid rock beneath the
old fringing-reef, will exceed by as many feet as there have been feet
of subsidence, that small limit of depth at which the effective corals
can live:--the little architects having built up their great wall-like
mass, as the whole sank down, upon a basis formed of other corals and
their consolidated fragments. Thus the difficulty on this head, which
appeared so great, disappears.

If, instead of an island, we had taken the shore of a continent fringed
with reefs, and had imagined it to have subsided, a great straight
barrier, like that of Australia or New Caledonia, separated from the
land by a wide and deep channel, would evidently have been the result.

Let us take our new encircling barrier-reef, of which the section is
now represented by unbroken lines, and which, as I have said, is a real
section through Bolabola, and let it go on subsiding.  As the
barrier-reef slowly sinks down, the corals will go on vigorously
growing upwards; but as the island sinks, the water will gain inch by
inch on the shore--the separate mountains first forming separate
islands within

[picture]

one great reef--and finally, the last and highest pinnacle
disappearing.  The instant this takes place, a perfect atoll is formed:
I have said, remove the high land from within an encircling
barrier-reef, and an atoll is left, and the land has been removed.  We
can now perceive how it comes that atolls, having sprung from
encircling barrier-reefs, resemble them in general size, form, in the
manner in which they are grouped together, and in their arrangement in
single or double lines; for they may be called rude outline charts of
the sunken islands over which they stand.  We can further see how it
arises that the atolls in the Pacific and Indian Oceans extend in lines
parallel to the generally prevailing strike of the high islands and
great coast-lines of those oceans.  I venture, therefore, to affirm,
that on the theory of the upward growth of the corals during the
sinking of the land, [13] all the leading features in those wonderful
structures, the lagoon-islands or atolls, which have so long excited
the attention of voyagers, as well as in the no less wonderful
barrier-reefs, whether encircling small islands or stretching for
hundreds of miles along the shores of a continent, are simply explained.

It may be asked, whether I can offer any direct evidence of the
subsidence of barrier-reefs or atolls; but it must be borne in mind how
difficult it must ever be to detect a movement, the tendency of which
is to hide under water the part affected.  Nevertheless, at Keeling
atoll I observed on all sides of the lagoon old cocoa-nut trees
undermined and falling; and in one place the foundation-posts of a
shed, which the inhabitants asserted had stood seven years before just
above high-water mark, but now was daily washed by every tide: on
inquiry I found that three earthquakes, one of them severe, had been
felt here during the last ten years.  At Vanikoro, the lagoon-channel
is remarkably deep, scarcely any alluvial soil has accumulated at the
foot of the lofty included mountains, and remarkably few islets have
been formed by the heaping of fragments and sand on the wall-like
barrier reef; these facts, and some analogous ones, led me to believe
that this island must lately have subsided and the reef grown upwards:
here again earthquakes are frequent and very severe.  In the Society
archipelago, on the other hand, where the lagoon-channels are almost
choked up, where much low alluvial land has accumulated, and where in
some cases long islets have been formed on the barrier-reefs--facts
all showing that the islands have not very lately subsided--only feeble
shocks are most rarely felt.  In these coral formations, where the land
and water seem struggling for mastery, it must be ever difficult to
decide between the effects of a change in the set of the tides and of a
slight subsidence: that many of these reefs and atolls are subject to
changes of some kind is certain; on some atolls the islets appear to
have increased greatly within a late period; on others they have been
partially or wholly washed away.  The inhabitants of parts of the
Maldiva archipelago know the date of the first formation of some
islets; in other parts, the corals are now flourishing on water-washed
reefs, where holes made for graves attest the former existence of
inhabited land.  It is difficult to believe in frequent changes in the
tidal currents of an open ocean; whereas, we have in the earthquakes
recorded by the natives on some atolls, and in the great fissures
observed on other atolls, plain evidence of changes and disturbances in
progress in the subterranean regions.

It is evident, on our theory, that coasts merely fringed by reefs
cannot have subsided to any perceptible amount; and therefore they
must, since the growth of their corals, either have remained stationary
or have been upheaved.  Now, it is remarkable how generally it can be
shown, by the presence of upraised organic remains, that the fringed
islands have been elevated: and so far, this is indirect evidence in
favour of our theory.  I was particularly struck with this fact, when I
found, to my surprise, that the descriptions given by MM. Quoy and
Gaimard were applicable, not to reefs in general as implied by them,
but only to those of the fringing class; my surprise, however, ceased
when I afterwards found that, by a strange chance, all the several
islands visited by these eminent naturalists, could be shown by their
own statements to have been elevated within a recent geological era.

Not only the grand features in the structure of barrier-reefs and of
atolls, and to their likeness to each other in form, size, and other
characters, are explained on the theory of subsidence--which theory we
are independently forced to admit in the very areas in question, from
the necessity of finding bases for the corals within the requisite
depth--but many details in structure and exceptional cases can thus
also be simply explained.  I will give only a few instances.  In
barrier-reefs it has long been remarked with surprise, that the
passages through the reef exactly face valleys in the included land,
even in cases where the reef is separated from the land by a
lagoon-channel so wide and so much deeper than the actual passage
itself, that it seems hardly possible that the very small quantity of
water or sediment brought down could injure the corals on the reef.
Now, every reef of the fringing class is breached by a narrow gateway
in front of the smallest rivulet, even if dry during the greater part
of the year, for the mud, sand, or gravel, occasionally washed down
kills the corals on which it is deposited.  Consequently, when an
island thus fringed subsides, though most of the narrow gateways will
probably become closed by the outward and upward growth of the corals,
yet any that are not closed (and some must always be kept open by the
sediment and impure water flowing out of the lagoon-channel) will still
continue to front exactly the upper parts of those valleys, at the
mouths of which the original basal fringing-reef was breached.

We can easily see how an island fronted only on one side, or on one
side with one end or both ends encircled by barrier-reefs, might after
long-continued subsidence be converted either into a single wall-like
reef, or into an atoll with a great straight spur projecting from it,
or into two or three atolls tied together by straight reefs--all of
which exceptional cases actually occur.  As the reef-building corals
require food, are preyed upon by other animals, are killed by sediment,
cannot adhere to a loose bottom, and may be easily carried down to a
depth whence they cannot spring up again, we need feel no surprise at
the reefs both of atolls and barriers becoming in parts imperfect.  The
great barrier of New Caledonia is thus imperfect and broken in many
parts; hence, after long subsidence, this great reef would not produce
one great atoll 400 miles in length, but a chain or archipelago of
atolls, of very nearly the same dimension with those in the Maldiva
archipelago.  Moreover, in an atoll once breached on opposite sides,
from the likelihood of the oceanic and tidal currents passing straight
through the breaches, it is extremely improbable that the corals,
especially during continued subsidence, would ever be able again to
unite the rim; if they did not, as the whole sank downwards, one atoll
would be divided into two or more.  In the Maldiva archipelago there
are distinct atolls so related to each other in position, and separated
by channels either unfathomable or very deep (the channel between Ross
and Ari atolls is 150 fathoms, and that between the north and south
Nillandoo atolls is 200 fathoms in depth), that it is impossible to
look at a map of them without believing that they were once more
intimately related.  And in this same archipelago, Mahlos-Mahdoo atoll
is divided by a bifurcating channel from 100 to 132 fathoms in depth,
in such a manner, that it is scarcely possible to say whether it ought
strictly to be called three separate atolls, or one great atoll not yet
finally divided.

I will not enter on many more details; but I must remark that the
curious structure of the northern Maldiva atolls receives (taking into
consideration the free entrance of the sea through their broken
margins) a simple explanation in the upward and outward growth of the
corals, originally based both on small detached reefs in their lagoons,
such as occur in common atolls, and on broken portions of the linear
marginal reef, such as bounds every atoll of the ordinary form.  I
cannot refrain from once again remarking on the singularity of these
complex structures--a great sandy and generally concave disk rises
abruptly from the unfathomable ocean, with its central expanse studded,
and its edge symmetrically bordered with oval basins of coral-rock just
lipping the surface of the sea, sometimes clothed with vegetation, and
each containing a lake of clear water!

One more point in detail: as in the two neighbouring archipelagoes
corals flourish in one and not in the other, and as so many conditions
before enumerated must affect their existence, it would be an
inexplicable fact if, during the changes to which earth, air, and water
are subjected, the reef-building corals were to keep alive for
perpetuity on any one spot or area.  And as by our theory the areas
including atolls and barrier-reefs are subsiding, we ought occasionally
to find reefs both dead and submerged.  In all reefs, owing to the
sediment being washed out of the lagoon-channel to leeward, that side
is least favourable to the long-continued vigorous growth of the
corals; hence dead portions of reef not unfrequently occur on the
leeward side; and these, though still retaining their proper wall-like
form, are now in several instances sunk several fathoms beneath the
surface.  The Chagos group appears from some cause, possibly from the
subsidence having been too rapid, at present to be much less favourably
circumstanced for the growth of reefs than formerly: one atoll has a
portion of its marginal reef, nine miles in length, dead and submerged;
a second has only a few quite small living points which rise to the
surface, a third and fourth are entirely dead and submerged; a fifth is
a mere wreck, with its structure almost obliterated.  It is remarkable
that in all these cases, the dead reefs and portions of reef lie at
nearly the same depth, namely, from six to eight fathoms beneath the
surface, as if they had been carried down by one uniform movement.  One
of these "half-drowned atolls," so called by Capt. Moresby (to whom I
am indebted for much invaluable information), is of vast size, namely,
ninety nautical miles across in one direction, and seventy miles in
another line; and is in many respects eminently curious.  As by our
theory it follows that new atolls will generally be formed in each new
area of subsidence, two weighty objections might have been raised,
namely, that atolls must be increasing indefinitely in number; and
secondly, that in old areas of subsidence each separate atoll must be
increasing indefinitely in thickness, if proofs of their occasional
destruction could not have been adduced. Thus have we traced the
history of these great rings of coral-rock, from their first origin
through their normal changes, and through the occasional accidents of
their existence, to their death and final obliteration.


In my volume on "Coral Formations" I have published a map, in which I
have coloured all the atolls dark-blue, the barrier-reefs pale-blue,
and the fringing reefs red.  These latter reefs have been formed whilst
the land has been stationary, or, as appears from the frequent presence
of upraised organic remains, whilst it has been slowly rising: atolls
and barrier-reefs, on the other hand, have grown up during the directly
opposite movement of subsidence, which movement must have been very
gradual, and in the case of atolls so vast in amount as to have buried
every mountain-summit over wide ocean-spaces.  Now in this map we see
that the reefs tinted pale and dark-blue, which have been produced by
the same order of movement, as a general rule manifestly stand near
each other.  Again we see, that the areas with the two blue tints are
of wide extent; and that they lie separate from extensive lines of
coast coloured red, both of which circumstances might naturally have
been inferred, on the theory of the nature of the reefs having been
governed by the nature of the earth's movement.  It deserves notice
that in more than one instance where single red and blue circles
approach near each other, I can show that there have been oscillations
of level; for in such cases the red or fringed circles consist of
atolls, originally by our theory formed during subsidence, but
subsequently upheaved; and on the other hand, some of the pale-blue or
encircled islands are composed of coral-rock, which must have been
uplifted to its present height before that subsidence took place,
during which the existing barrier-reefs grew upwards.

Authors have noticed with surprise, that although atolls are the
commonest coral-structures throughout some enormous oceanic tracts,
they are entirely absent in other seas, as in the West Indies: we can
now at once perceive the cause, for where there has not been
subsidence, atolls cannot have been formed; and in the case of the West
Indies and parts of the East Indies, these tracts are known to have
been rising within the recent period.  The larger areas, coloured red
and blue, are all elongated; and between the two colours there is a
degree of rude alternation, as if the rising of one had balanced the
sinking of the other.  Taking into consideration the proofs of recent
elevation both on the fringed coasts and on some others (for instance,
in South America) where there are no reefs, we are led to conclude that
the great continents are for the most part rising areas: and from the
nature of the coral-reefs, that the central parts of the great oceans
are sinking areas.  The East Indian archipelago, the most broken land
in the world, is in most parts an area of elevation, but surrounded and
penetrated, probably in more lines than one, by narrow areas of
subsidence.

I have marked with vermilion spots all the many known active volcanos
within the limits of this same map.  Their entire absence from every
one of the great subsiding areas, coloured either pale or dark blue, is
most striking and not less so is the coincidence of the chief volcanic
chains with the parts coloured red, which we are led to conclude have
either long remained stationary, or more generally have been recently
upraised.  Although a few of the vermilion spots occur within no great
distance of single circles tinted blue, yet not one single active
volcano is situated within several hundred miles of an archipelago, or
even small group of atolls.  It is, therefore, a striking fact that in
the Friendly archipelago, which consists of a group of atolls upheaved
and since partially worn down, two volcanos, and perhaps more, are
historically known to have been in action.  On the other hand, although
most of the islands in the Pacific which are encircled by
barrier-reefs, are of volcanic origin, often with the remnants of
craters still distinguishable, not one of them is known to have ever
been in eruption.  Hence in these cases it would appear, that volcanos
burst forth into action and become extinguished on the same spots,
accordingly as elevatory or subsiding movements prevail there.
Numberless facts could be adduced to prove that upraised organic
remains are common wherever there are active volcanos; but until it
could be shown that in areas of subsidence, volcanos were either absent
or inactive, the inference, however probable in itself, that their
distribution depended on the rising or falling of the earth's surface,
would have been hazardous.  But now, I think, we may freely admit this
important deduction.

Taking a final view of the map, and bearing in mind the statements made
with respect to the upraised organic remains, we must feel astonished
at the vastness of the areas, which have suffered changes in level
either downwards or upwards, within a period not geologically remote.
It would appear also, that the elevatory and subsiding movements follow
nearly the same laws.  Throughout the spaces interspersed with atolls,
where not a single peak of high land has been left above the level of
the sea, the sinking must have been immense in amount.  The sinking,
moreover, whether continuous, or recurrent with intervals sufficiently
long for the corals again to bring up their living edifices to the
surface, must necessarily have been extremely slow.  This conclusion is
probably the most important one which can be deduced from the study of
coral formations;--and it is one which it is difficult to imagine how
otherwise could ever have been arrived at.  Nor can I quite pass over
the probability of the former existence of large archipelagoes of lofty
islands, where now only rings of coral-rock scarcely break the open
expanse of the sea, throwing some light on the distribution of the
inhabitants of the other high islands, now left standing so immensely
remote from each other in the midst of the great oceans.  The
reef-constructing corals have indeed reared and preserved wonderful
memorials of the subterranean oscillations of level; we see in each
barrier-reef a proof that the land has there subsided, and in each
atoll a monument over an island now lost.  We may thus, like unto a
geologist who had lived his ten thousand years and kept a record of the
passing changes, gain some insight into the great system by which the
surface of this globe has been broken up, and land and water
interchanged.

[1] These Plants are described in the Annals of Nat. Hist., vol. i.,
1838, p. 337.

[2] Holman's Travels, vol. iv. p. 378.

[3] Kotzebue's First Voyage, vol. iii. p. 155.

[4] The thirteen species belong to the following orders:--In the
Coleoptera, a minute Elater; Orthoptera, a Gryllus and a Blatta;
Hemiptera, one species; Homoptera, two; Neuroptera a Chrysopa;
Hymenoptera, two ants; Lepidoptera nocturna, a Diopaea, and a
Pterophorus (?); Diptera, two species.

[5] Kotzebue's First Voyage, vol. iii. p. 222.

[6] The large claws or pincers of some of these crabs are most
beautifully adapted, when drawn back, to form an operculum to the
shell, nearly as perfect as the proper one originally belonging to the
molluscous animal.  I was assured, and as far as my observations went I
found it so, that certain species of the hermit-crab always use certain
species of shells.

[7] Some natives carried by Kotzebue to Kamtschatka collected stones to
take back to their country.

[8] See Proceedings of Zoological Society, 1832, p. 17.

[9] Tyerman and Bennett. Voyage, etc. vol. ii. p. 33.

[10] I exclude, of course, some soil which has been imported here in
vessels from Malacca and Java, and likewise, some small fragments of
pumice, drifted here by the waves.  The one block of greenstone,
moreover, on the northern island must be excepted.

[11] These were first read before the Geological Society in May, 1837,
and have since been developed in a separate volume on the "Structure
and Distribution of Coral Reefs."

[12] It is remarkable that Mr. Lyell, even in the first edition of his
"Principles of Geology," inferred that the amount of subsidence in the
Pacific must have exceeded that of elevation, from the area of land
being very small relatively to the agents there tending to form it,
namely, the growth of coral and volcanic action.

[13] It has been highly satisfactory to me to find the following
passage in a pamphlet by Mr. Couthouy, one of the naturalists in the
great Antarctic Expedition of the United States:--"Having personally
examined a large number of coral-islands and resided eight months among
the volcanic class having shore and partially encircling reefs.  I may
be permitted to state that my own observations have impressed a
conviction of the correctness of the theory of Mr. Darwin."--The
naturalists, however, of this expedition differ with me on some points
respecting coral formations.



CHAPTER XXI

MAURITIUS TO ENGLAND

Mauritius, beautiful appearance of--Great crateriform ring of
Mountains--Hindoos--St. Helena--History of the changes in the
Vegetation--Cause of the extinction of
Land-shells--Ascension--Variation in the imported Rats--Volcanic
Bombs--Beds of Infusoria--Bahia--Brazil--Splendour of Tropical
Scenery--Pernambuco--Singular Reef--Slavery--Return to
England--Retrospect on our Voyage.


APRIL 29th.--In the morning we passed round the northern end of
Mauritius, or the Isle of France. From this point of view the aspect of
the island equalled the expectations raised by the many well-known
descriptions of its beautiful scenery.  The sloping plain of the
Pamplemousses, interspersed with houses, and coloured by the large
fields of sugar-cane of a bright green, composed the foreground.  The
brilliancy of the green was the more remarkable because it is a colour
which generally is conspicuous only from a very short distance. Towards
the centre of the island groups of wooded mountains rose out of this
highly cultivated plain; their summits, as so commonly happens with
ancient volcanic rocks, being jagged into the sharpest points. Masses
of white clouds were collected around these pinnacles, as if for the
sake of pleasing the stranger's eye.  The whole island, with its
sloping border and central mountains, was adorned with an air of
perfect elegance: the scenery, if I may use such an expression,
appeared to the sight harmonious.

I spent the greater part of the next day in walking about the town and
visiting different people.  The town is of considerable size, and is
said to contain 20,000 inhabitants; the streets are very clean and
regular.  Although the island has been so many years under the English
Government, the general character of the place is quite French:
Englishmen speak to their servants in French, and the shops are all
French; indeed, I should think that Calais or Boulogne was much more
Anglified.  There is a very pretty little theatre, in which operas are
excellently performed.  We were also surprised at seeing large
booksellers' shops, with well-stored shelves;--music and reading
bespeak our approach to the old world of civilization; for in truth
both Australia and America are new worlds.

The various races of men walking in the streets afford the most
interesting spectacle in Port Louis.  Convicts from India are banished
here for life; at present there are about 800, and they are employed in
various public works.  Before seeing these people, I had no idea that
the inhabitants of India were such noble-looking figures.  Their skin
is extremely dark, and many of the older men had large mustaches and
beards of a snow-white colour; this, together with the fire of their
expression, gave them quite an imposing aspect.  The greater number had
been banished for murder and the worst crimes; others for causes which
can scarcely be considered as moral faults, such as for not obeying,
from superstitious motives, the English laws.  These men are generally
quiet and well-conducted; from their outward conduct, their
cleanliness, and faithful observance of their strange religious rites,
it was impossible to look at them with the same eyes as on our wretched
convicts in New South Wales.

May 1st.--Sunday.  I took a quiet walk along the sea-coast to the north
of the town.  The plain in this part is quite uncultivated; it consists
of a field of black lava, smoothed over with coarse grass and bushes,
the latter being chiefly Mimosas.  The scenery may be described as
intermediate in character between that of the Galapagos and of Tahiti;
but this will convey a definite idea to very few persons.  It is a very
pleasant country, but it has not the charms of Tahiti, or the grandeur
of Brazil.  The next day I ascended La Pouce, a mountain so called from
a thumb-like projection, which rises close behind the town to a height
of 2,600 feet.  The centre of the island consists of a great platform,
surrounded by old broken basaltic mountains, with their strata dipping
seawards.  The central platform, formed of comparatively recent streams
of lava, is of an oval shape, thirteen geographical miles across, in
the line of its shorter axis.  The exterior bounding mountains come
into that class of structures called Craters of Elevation, which are
supposed to have been formed not like ordinary craters, but by a great
and sudden upheaval.  There appears to me to be insuperable objections
to this view: on the other hand, I can hardly believe, in this and in
some other cases, that these marginal crateriform mountains are merely
the basal remnants of immense volcanos, of which the summits either
have been blown off, or swallowed up in subterranean abysses.

From our elevated position we enjoyed an excellent view over the
island.  The country on this side appears pretty well cultivated, being
divided into fields and studded with farm-houses. I was, however,
assured that of the whole land, not more than half is yet in a
productive state; if such be the case, considering the present large
export of sugar, this island, at some future period when thickly
peopled, will be of great value.  Since England has taken possession of
it, a period of only twenty-five years, the export of sugar is said to
have increased seventy-five fold.  One great cause of its prosperity is
the excellent state of the roads.  In the neighbouring Isle of Bourbon,
which remains under the French government, the roads are still in the
same miserable state as they were here only a few years ago.  Although
the French residents must have largely profited by the increased
prosperity of their island, yet the English government is far from
popular.

3rd.--In the evening Captain Lloyd, the Surveyor-general, so well known
from his examination of the Isthmus of Panama, invited Mr. Stokes and
myself to his country-house, which is situated on the edge of Wilheim
Plains, and about six miles from the Port.  We stayed at this
delightful place two days; standing nearly 800 feet above the sea, the
air was cool and fresh, and on every side there were delightful walks.
Close by, a grand ravine has been worn to a depth of about 500 feet
through the slightly inclined streams of lava, which have flowed from
the central platform.

5th.--Captain Lloyd took us to the Riviere Noire, which is several
miles to the southward, that I might examine some rocks of elevated
coral.  We passed through pleasant gardens, and fine fields of
sugar-cane growing amidst huge blocks of lava.  The roads were bordered
by hedges of Mimosa, and near many of the houses there were avenues of
the mango.  Some of the views, where the peaked hills and the
cultivated farms were seen together, were exceedingly picturesque; and
we were constantly tempted to exclaim, "How pleasant it would be to
pass one's life in such quiet abodes!" Captain Lloyd possessed an
elephant, and he sent it half way with us, that we might enjoy a ride
in true Indian fashion.  The circumstance which surprised me most was
its quite noiseless step.  This elephant is the only one at present on
the island; but it is said others will be sent for.


May 9th.--We sailed from Port Louis, and, calling at the Cape of Good
Hope, on the 8th of July, we arrived off St. Helena.  This island, the
forbidding aspect of which has been so often described, rises abruptly
like a huge black castle from the ocean.  Near the town, as if to
complete nature's defence, small forts and guns fill up every gap in
the rugged rocks.  The town runs up a flat and narrow valley; the
houses look respectable, and are interspersed with a very few green
trees.  When approaching the anchorage there was one striking view: an
irregular castle perched on the summit of a lofty hill, and surrounded
by a few scattered fir-trees, boldly projected against the sky.

The next day I obtained lodgings within a stone's throw of Napoleon's
tomb; [1] it was a capital central situation, whence I could make
excursions in every direction.  During the four days I stayed here, I
wandered over the island from morning to night, and examined its
geological history.  My lodgings were situated at a height of about
2000 feet; here the weather was cold and boisterous, with constant
showers of rain; and every now and then the whole scene was veiled in
thick clouds.

Near the coast the rough lava is quite bare: in the central and higher
parts, feldspathic rocks by their decomposition have produced a clayey
soil, which, where not covered by vegetation, is stained in broad bands
of many bright colours. At this season, the land moistened by constant
showers, produces a singularly bright green pasture, which lower and
lower down, gradually fades away and at last disappears.  In latitude
16 degs., and at the trifling elevation of 1500 feet, it is surprising
to behold a vegetation possessing a character decidedly British.  The
hills are crowned with irregular plantations of Scotch firs; and the
sloping banks are thickly scattered over with thickets of gorse,
covered with its bright yellow flowers.  Weeping-willows are common on
the banks of the rivulets, and the hedges are made of the blackberry,
producing its well-known fruit.  When we consider that the number of
plants now found on the island is 746, and that out of these fifty-two
alone are indigenous species, the rest having been imported, and most
of them from England, we see the reason of the British character of the
vegetation. Many of these English plants appear to flourish better than
in their native country; some also from the opposite quarter of
Australia succeed remarkably well.  The many imported species must have
destroyed some of the native kinds; and it is only on the highest and
steepest ridges that the indigenous Flora is now predominant.

The English, or rather Welsh character of the scenery, is kept up by
the numerous cottages and small white houses; some buried at the bottom
of the deepest valleys, and others mounted on the crests of the lofty
hills.  Some of the views are striking, for instance that from near Sir
W. Doveton's house, where the bold peak called Lot is seen over a dark
wood of firs, the whole being backed by the red water-worn mountains of
the southern coast.  On viewing the island from an eminence, the first
circumstance which strikes one, is the number of the roads and forts:
the labour bestowed on the public works, if one forgets its character
as a prison, seems out of all proportion to its extent or value.  There
is so little level or useful land, that it seems surprising how so many
people, about 5000, can subsist here.  The lower orders, or the
emancipated slaves, are I believe extremely poor: they complain of the
want of work.  From the reduction in the number of public servants
owing to the island having been given up by the East Indian Company,
and the consequent emigration of many of the richer people, the poverty
probably will increase.  The chief food of the working class is rice
with a little salt meat; as neither of these articles are the products
of the island, but must be purchased with money, the low wages tell
heavily on the poor people. Now that the people are blessed with
freedom, a right which I believe they value fully, it seems probable
that their numbers will quickly increase: if so, what is to become of
the little state of St. Helena?

My guide was an elderly man, who had been a goatherd when a boy, and
knew every step amongst the rocks.  He was of a race many times
crossed, and although with a dusky skin, he had not the disagreeable
expression of a mulatto.  He was a very civil, quiet old man, and such
appears the character of the greater number of the lower classes.  It
was strange to my ears to hear a man, nearly white and respectably
dressed, talking with indifference of the times when he was a slave.
With my companion, who carried our dinners and a horn of water, which
is quite necessary, as all the water in the lower valleys is saline, I
every day took long walks.

Beneath the upper and central green circle, the wild valleys are quite
desolate and untenanted.  Here, to the geologist, there were scenes of
high interest, showing successive changes and complicated disturbances.
According to my views, St. Helena has existed as an island from a very
remote epoch: some obscure proofs, however, of the elevation of the
land are still extant.  I believe that the central and highest peaks
form parts of the rim of a great crater, the southern half of which has
been entirely removed by the waves of the sea: there is, moreover, an
external wall of black basaltic rocks, like the coast-mountains of
Mauritius, which are older than the central volcanic streams.  On the
higher parts of the island, considerable numbers of a shell, long
thought to be a marine species occur imbedded in the soil.

It proved to be a Cochlogena, or land-shell of a very peculiar form;
[2] with it I found six other kinds; and in another spot an eighth
species.  It is remarkable that none of them are now found living.
Their extinction has probably been caused by the entire destruction of
the woods, and the consequent loss of food and shelter, which occurred
during the early part of the last century.

The history of the changes, which the elevated plains of Longwood and
Deadwood have undergone, as given in General Beatson's account of the
island, is extremely curious. Both plains, it is said in former times
were covered with wood, and were therefore called the Great Wood.  So
late as the year 1716 there were many trees, but in 1724 the old trees
had mostly fallen; and as goats and hogs had been suffered to range
about, all the young trees had been killed. It appears also from the
official records, that the trees were unexpectedly, some years
afterwards, succeeded by a wire grass which spread over the whole
surface. [3] General Beatson adds that now this plain "is covered with
fine sward, and is become the finest piece of pasture on the island."
The extent of surface, probably covered by wood at a former period, is
estimated at no less than two thousand acres; at the present day
scarcely a single tree can be found there.  It is also said that in
1709 there were quantities of dead trees in Sandy Bay; this place is
now so utterly desert, that nothing but so well attested an account
could have made me believe that they could ever have grown there.  The
fact, that the goats and hogs destroyed all the young trees as they
sprang up, and that in the course of time the old ones, which were safe
from their attacks, perished from age, seems clearly made out.  Goats
were introduced in the year 1502; eighty-six years afterwards, in the
time of Cavendish, it is known that they were exceedingly numerous.
More than a century afterwards, in 1731, when the evil was complete and
irretrievable, an order was issued that all stray animals should be
destroyed.  It is very interesting thus to find, that the arrival of
animals at St. Helena in 1501, did not change the whole aspect of the
island, until a period of two hundred and twenty years had elapsed: for
the goats were introduced in 1502, and in 1724 it is said "the old
trees had mostly fallen." There can be little doubt that this great
change in the vegetation affected not only the land-shells, causing
eight species to become extinct, but likewise a multitude of insects.

St. Helena, situated so remote from any continent, in the midst of a
great ocean, and possessing a unique Flora, excites our curiosity.  The
eight land-shells, though now extinct, and one living Succinea, are
peculiar species found nowhere else.  Mr. Cuming, however, informs me
that an English Helix is common here, its eggs no doubt having been
imported in some of the many introduced plants.  Mr. Cuming collected
on the coast sixteen species of sea-shells, of which seven, as far as
he knows, are confined to this island.  Birds and insects, [4] as might
have been expected, are very few in number; indeed I believe all the
birds have been introduced within late years.  Partridges and pheasants
are tolerably abundant; the island is much too English not to be
subject to strict game-laws.  I was told of a more unjust sacrifice to
such ordinances than I ever heard of even in England.  The poor people
formerly used to burn a plant, which grows on the coast-rocks, and
export the soda from its ashes; but a peremptory order came out
prohibiting this practice, and giving as a reason that the partridges
would have nowhere to build.

In my walks I passed more than once over the grassy plain bounded by
deep valleys, on which Longwood stands. Viewed from a short distance,
it appears like a respectable gentleman's country-seat.  In front there
are a few cultivated fields, and beyond them the smooth hill of
coloured rocks called the Flagstaff, and the rugged square black mass
of the Barn.  On the whole the view was rather bleak and uninteresting.
The only inconvenience I suffered during my walks was from the
impetuous winds.  One day I noticed a curious circumstance; standing on
the edge of a plain, terminated by a great cliff of about a thousand
feet in depth, I saw at the distance of a few yards right to windward,
some tern, struggling against a very strong breeze, whilst, where I
stood, the air was quite calm.  Approaching close to the brink, where
the current seemed to be deflected upwards from the face of the cliff,
I stretched out my arm, and immediately felt the full force of the
wind: an invisible barrier, two yards in width, separated perfectly
calm air from a strong blast.

I so much enjoyed my rambles among the rocks and mountains of St.
Helena, that I felt almost sorry on the morning of the 14th to descend
to the town.  Before noon I was on board, and the Beagle made sail.

On the 19th of July we reached Ascension.  Those who have beheld a
volcanic island, situated under an arid climate, will at once be able
to picture to themselves the appearance of Ascension.  They will
imagine smooth conical hills of a bright red colour, with their summits
generally truncated, rising separately out of a level surface of black
rugged lava. A principal mound in the centre of the island, seems the
father of the lesser cones.  It is called Green Hill: its name being
taken from the faintest tinge of that colour, which at this time of the
year is barely perceptible from the anchorage.  To complete the
desolate scene, the black rocks on the coast are lashed by a wild and
turbulent sea.

The settlement is near the beach; it consists of several houses and
barracks placed irregularly, but well built of white freestone.  The
only inhabitants are marines, and some negroes liberated from
slave-ships, who are paid and victualled by government.  There is not a
private person on the island.  Many of the marines appeared well
contented with their situation; they think it better to serve their
one-and-twenty years on shore, let it be what it may, than in a ship;
in this choice, if I were a marine, I should most heartily agree.

The next morning I ascended Green Hill, 2840 feet high, and thence
walked across the island to the windward point. A good cart-road leads
from the coast-settlement to the houses, gardens, and fields, placed
near the summit of the central mountain.  On the roadside there are
milestones, and likewise cisterns, where each thirsty passer-by can
drink some good water.  Similar care is displayed in each part of the
establishment, and especially in the management of the springs, so that
a single drop of water may not be lost: indeed the whole island may be
compared to a huge ship kept in first-rate order.  I could not help,
when admiring the active industry, which had created such effects out
of such means, at the same time regretting that it had been wasted on
so poor and trifling an end.  M. Lesson has remarked with justice, that
the English nation would have thought of making the island of Ascension
a productive spot, any other people would have held it as a mere
fortress in the ocean.

Near this coast nothing grows; further inland, an occasional green
castor-oil plant, and a few grasshoppers, true friends of the desert,
may be met with.  Some grass is scattered over the surface of the
central elevated region, and the whole much resembles the worse parts
of the Welsh mountains. But scanty as the pasture appears, about six
hundred sheep, many goats, a few cows and horses, all thrive well on
it.  Of native animals, land-crabs and rats swarm in numbers. Whether
the rat is really indigenous, may well be doubted; there are two
varieties as described by Mr. Waterhouse; one is of a black colour,
with fine glossy fur, and lives on the grassy summit, the other is
brown-coloured and less glossy, with longer hairs, and lives near the
settlement on the coast.  Both these varieties are one-third smaller
than the common black rat (M. rattus); and they differ from it both in
the colour and character of their fur, but in no other essential
respect.  I can hardly doubt that these rats (like the common mouse,
which has also run wild) have been imported, and, as at the Galapagos,
have varied from the effect of the new conditions to which they have
been exposed: hence the variety on the summit of the island differs
from that on the coast.  Of native birds there are none; but the
guinea-fowl, imported from the Cape de Verd Islands, is abundant, and
the common fowl has likewise run wild.  Some cats, which were
originally turned out to destroy the rats and mice, have increased, so
as to become a great plague.  The island is entirely without trees, in
which, and in every other respect, it is very far inferior to St.
Helena.

One of my excursions took me towards the S. W. extremity of the island.
The day was clear and hot, and I saw the island, not smiling with
beauty, but staring with naked hideousness.  The lava streams are
covered with hummocks, and are rugged to a degree which, geologically
speaking, is not of easy explanation.  The intervening spaces are
concealed with layers of pumice, ashes and volcanic tuff.  Whilst
passing this end of the island at sea, I could not imagine what the
white patches were with which the whole plain was mottled; I now found
that they were seafowl, sleeping in such full confidence, that even in
midday a man could walk up and seize hold of them.  These birds were
the only living creatures I saw during the whole day.  On the beach a
great surf, although the breeze was light, came tumbling over the
broken lava rocks.

The geology of this island is in many respects interesting. In several
places I noticed volcanic bombs, that is, masses of lava which have
been shot through the air whilst fluid, and have consequently assumed a
spherical or pear-shape.  Not only their external form, but, in several
cases, their internal structure shows in a very curious manner that
they have revolved in their aerial course.  The internal structure of
one of these bombs, when broken, is represented very accurately in the
woodcut.  The central part is coarsely cellular, the cells decreasing
in size towards the exterior; where there is a shell-like case about
the third of an inch in thickness, of compact stone, which again is
overlaid by the outside crust of finely cellular lava.  I think there
can be little doubt, first that the external crust cooled rapidly in
the state in which we now see it; secondly, that the still fluid lava
within, was packed by the centrifugal force, generated by

[picture]

the revolving of the bomb, against the external cooled crust, and so
produced the solid shell of stone; and lastly, that the centrifugal
force, by relieving the pressure in the more central parts of the bomb,
allowed the heated vapours to expand their cells, thus forming the
coarse cellular mass of the centre.

A hill, formed of the older series of volcanic rocks, and which has
been incorrectly considered as the crater of a volcano, is remarkable
from its broad, slightly hollowed, and circular summit having been
filled up with many successive layers of ashes and fine scoriae.  These
saucer-shaped layers crop out on the margin, forming perfect rings of
many different colours, giving to the summit a most fantastic
appearance; one of these rings is white and broad, and resembles a
course round which horses have been exercised; hence the hill has been
called the Devil's Riding School.  I brought away specimens of one of
the tufaceous layers of a pinkish colour and it is a most extraordinary
fact, that Professor Ehrenberg [5] finds it almost wholly composed of
matter which has been organized: he detects in it some
siliceous-shielded fresh-water infusoria, and no less than twenty-five
different kinds of the siliceous tissue of plants, chiefly of grasses.
From the absence of all carbonaceous matter, Professor Ehrenberg
believes that these organic bodies have passed through the volcanic
fire, and have been erupted in the state in which we now see them.  The
appearance of the layers induced me to believe that they had been
deposited under water, though from the extreme dryness of the climate I
was forced to imagine, that torrents of rain had probably fallen during
some great eruption, and that thus a temporary lake had been formed
into which the ashes fell.  But it may now be suspected that the lake
was not a temporary one.  Anyhow, we may feel sure, that at some former
epoch the climate and productions of Ascension were very different from
what they now are.  Where on the face of the earth can we find a spot,
on which close investigation will not discover signs of that endless
cycle of change, to which this earth has been, is, and will be
subjected?

On leaving Ascension, we sailed for Bahia, on the coast of Brazil, in
order to complete the chronometrical measurement of the world.  We
arrived there on August 1st, and stayed four days, during which I took
several long walks. I was glad to find my enjoyment in tropical scenery
had not decreased from the want of novelty, even in the slightest
degree.  The elements of the scenery are so simple, that they are worth
mentioning, as a proof on what trifling circumstances exquisite natural
beauty depends.

The country may be described as a level plain of about three hundred
feet in elevation, which in all parts has been worn into flat-bottomed
valleys.  This structure is remarkable in a granitic land, but is
nearly universal in all those softer formations of which plains are
usually composed. The whole surface is covered by various kinds of
stately trees, interspersed with patches of cultivated ground, out of
which houses, convents, and chapels arise.  It must be remembered that
within the tropics, the wild luxuriance of nature is not lost even in
the vicinity of large cities: for the natural vegetation of the hedges
and hill-sides overpowers in picturesque effect the artificial labour
of man. Hence, there are only a few spots where the bright red soil
affords a strong contrast with the universal clothing of green.  From
the edges of the plain there are distant views either of the ocean, or
of the great Bay with its low-wooded shores, and on which numerous
boats and canoes show their white sails.  Excepting from these points,
the scene is extremely limited; following the level pathways, on each
hand, only glimpses into the wooded valleys below can be obtained.  The
houses I may add, and especially the sacred edifices, are built in a
peculiar and rather fantastic style of architecture.  They are all
whitewashed; so that when illumined by the brilliant sun of midday, and
as seen against the pale blue sky of the horizon, they stand out more
like shadows than real buildings.

Such are the elements of the scenery, but it is a hopeless attempt to
paint the general effect.  Learned naturalists describe these scenes of
the tropics by naming a multitude of objects, and mentioning some
characteristic feature of each. To a learned traveller this possibly
may communicate some definite ideas: but who else from seeing a plant
in an herbarium can imagine its appearance when growing in its native
soil?  Who from seeing choice plants in a hothouse, can magnify some
into the dimensions of forest trees, and crowd others into an entangled
jungle?  Who when examining in the cabinet of the entomologist the gay
exotic butterflies, and singular cicadas, will associate with these
lifeless objects, the ceaseless harsh music of the latter, and the lazy
flight of the former,--the sure accompaniments of the still, glowing
noon-day of the tropics?  It is when the sun has attained its greatest
height, that such scenes should be viewed: then the dense splendid
foliage of the mango hides the ground with its darkest shade, whilst
the upper branches are rendered from the profusion of light of the most
brilliant green.  In the temperate zones the case is different--the
vegetation there is not so dark or so rich, and hence the rays of the
declining sun, tinged of a red, purple, or bright yellow color, add
most to the beauties of those climes.

When quietly walking along the shady pathways, and admiring each
successive view, I wished to find language to express my ideas. Epithet
after epithet was found too weak to convey to those who have not
visited the intertropical regions, the sensation of delight which the
mind experiences. I have said that the plants in a hothouse fail to
communicate a just idea of the vegetation, yet I must recur to it.  The
land is one great wild, untidy, luxuriant hothouse, made by Nature for
herself, but taken possession of by man, who has studded it with gay
houses and formal gardens.  How great would be the desire in every
admirer of nature to behold, if such were possible, the scenery of
another planet! yet to every person in Europe, it may be truly said,
that at the distance of only a few degrees from his native soil, the
glories of another world are opened to him.  In my last walk I stopped
again and again to gaze on these beauties, and endeavoured to fix in my
mind for ever, an impression which at the time I knew sooner or later
must fail.  The form of the orange-tree, the cocoa-nut, the palm, the
mango, the tree-fern, the banana, will remain clear and separate; but
the thousand beauties which unite these into one perfect scene must
fade away: yet they will leave, like a tale heard in childhood, a
picture full of indistinct, but most beautiful figures.

August 6th.--In the afternoon we stood out to sea, with the intention
of making a direct course to the Cape de Verd Islands.  Unfavourable
winds, however, delayed us, and on the 12th we ran into Pernambuco,--a
large city on the coast of Brazil, in latitude 8 degs. south.  We
anchored outside the reef; but in a short time a pilot came on board
and took us into the inner harbour, where we lay close to the town.

Pernambuco is built on some narrow and low sand-banks, which are
separated from each other by shoal channels of salt water.  The three
parts of the town are connected together by two long bridges built on
wooden piles.  The town is in all parts disgusting, the streets being
narrow, ill-paved, and filthy; the houses, tall and gloomy.  The season
of heavy rains had hardly come to an end, and hence the surrounding
country, which is scarcely raised above the level of the sea, was
flooded with water; and I failed in all my attempts to take walks.

The flat swampy land on which Pernambuco stands is surrounded, at the
distance of a few miles, by a semicircle of low hills, or rather by the
edge of a country elevated perhaps two hundred feet above the sea.  The
old city of Olinda stands on one extremity of this range.  One day I
took a canoe, and proceeded up one of the channels to visit it; I found
the old town from its situation both sweeter and cleaner than that of
Pernambuco.  I must here commemorate what happened for the first time
during our nearly five years' wandering, namely, having met with a want
of politeness. I was refused in a sullen manner at two different
houses, and obtained with difficulty from a third, permission to pass
through their gardens to an uncultivated hill, for the purpose of
viewing the country.  I feel glad that this happened in the land of the
Brazilians, for I bear them no good will--a land also of slavery, and
therefore of moral debasement.  A Spaniard would have felt ashamed at
the very thought of refusing such a request, or of behaving to a
stranger with rudeness.  The channel by which we went to and returned
from Olinda, was bordered on each side by mangroves, which sprang like
a miniature forest out of the greasy mud-banks.  The bright green
colour of these bushes always reminded me of the rank grass in a
church-yard: both are nourished by putrid exhalations; the one speaks
of death past, and the other too often of death to come.

The most curious object which I saw in this neighbourhood, was the reef
that forms the harbour.  I doubt whether in the whole world any other
natural structure has so artificial an appearance. [6] It runs for a
length of several miles in an absolutely straight line, parallel to,
and not far distant from, the shore.  It varies in width from thirty to
sixty yards, and its surface is level and smooth; it is composed of
obscurely stratified hard sandstone.  At high water the waves break
over it; at low water its summit is left dry, and it might then be
mistaken for a breakwater erected by Cyclopean workmen.  On this coast
the currents of the sea tend to throw up in front of the land, long
spits and bars of loose sand, and on one of these, part of the town of
Pernambuco stands.  In former times a long spit of this nature seems to
have become consolidated by the percolation of calcareous matter, and
afterwards to have been gradually upheaved; the outer and loose parts
during this process having been worn away by the action of the sea, and
the solid nucleus left as we now see it.  Although night and day the
waves of the open Atlantic, turbid with sediment, are driven against
the steep outside edges of this wall of stone, yet the oldest pilots
know of no tradition of any change in its appearance.  This durability
is much the most curious fact in its history: it is due to a tough
layer, a few inches thick, of calcareous matter, wholly formed by the
successive growth and death of the small shells of Serpulae, together
with some few barnacles and nulliporae.  These nulliporae, which are
hard, very simply-organized sea-plants, play an analogous and important
part in protecting the upper surfaces of coral-reefs, behind and within
the breakers, where the true corals, during the outward growth of the
mass, become killed by exposure to the sun and air.  These
insignificant organic beings, especially the Serpulae, have done good
service to the people of Pernambuco; for without their protective aid
the bar of sandstone would inevitably have been long ago worn away and
without the bar, there would have been no harbour.

On the 19th of August we finally left the shores of Brazil. I thank
God, I shall never again visit a slave-country.  To this day, if I hear
a distant scream, it recalls with painful vividness my feelings, when
passing a house near Pernambuco, I heard the most pitiable moans, and
could not but suspect that some poor slave was being tortured, yet knew
that I was as powerless as a child even to remonstrate.  I suspected
that these moans were from a tortured slave, for I was told that this
was the case in another instance.  Near Rio de Janeiro I lived opposite
to an old lady, who kept screws to crush the fingers of her female
slaves.  I have stayed in a house where a young household mulatto,
daily and hourly, was reviled, beaten, and persecuted enough to break
the spirit of the lowest animal.  I have seen a little boy, six or
seven years old, struck thrice with a horse-whip (before I could
interfere) on his naked head, for having handed me a glass of water not
quite clean; I saw his father tremble at a mere glance from his
master's eye. These latter cruelties were witnessed by me in a Spanish
colony, in which it has always been said, that slaves are better
treated than by the Portuguese, English, or other European nations.  I
have seen at Rio de Janeiro a powerful negro afraid to ward off a blow
directed, as he thought, at his face.  I was present when a
kind-hearted man was on the point of separating forever the men, women,
and little children of a large number of families who had long lived
together.  I will not even allude to the many heart-sickening
atrocities which I authentically heard of;--nor would I have mentioned
the above revolting details, had I not met with several people, so
blinded by the constitutional gaiety of the negro as to speak of
slavery as a tolerable evil.  Such people have generally visited at the
houses of the upper classes, where the domestic slaves are usually well
treated, and they have not, like myself, lived amongst the lower
classes.  Such inquirers will ask slaves about their condition; they
forget that the slave must indeed be dull, who does not calculate on
the chance of his answer reaching his master's ears.

It is argued that self-interest will prevent excessive cruelty; as if
self-interest protected our domestic animals, which are far less likely
than degraded slaves, to stir up the rage of their savage masters.  It
is an argument long since protested against with noble feeling, and
strikingly exemplified, by the ever-illustrious Humboldt.  It is often
attempted to palliate slavery by comparing the state of slaves with our
poorer countrymen: if the misery of our poor be caused not by the laws
of nature, but by our institutions, great is our sin; but how this
bears on slavery, I cannot see; as well might the use of the
thumb-screw be defended in one land, by showing that men in another
land suffered from some dreadful disease.  Those who look tenderly at
the slave owner, and with a cold heart at the slave, never seem to put
themselves into the position of the latter; what a cheerless prospect,
with not even a hope of change! picture to yourself the chance, ever
hanging over you, of your wife and your little children--those objects
which nature urges even the slave to call his own--being torn from you
and sold like beasts to the first bidder!  And these deeds are done and
palliated by men, who profess to love their neighbours as themselves,
who believe in God, and pray that his Will be done on earth!  It makes
one's blood boil, yet heart tremble, to think that we Englishmen and
our American descendants, with their boastful cry of liberty, have been
and are so guilty: but it is a consolation to reflect, that we at least
have made a greater sacrifice, than ever made by any nation, to expiate
our sin.


On the last day of August we anchored for the second time at Porto
Praya in the Cape de Verd archipelago; thence we proceeded to the
Azores, where we stayed six days.  On the 2nd of October we made the
shore, of England; and at Falmouth I left the Beagle, having lived on
board the good little vessel nearly five years.


Our Voyage having come to an end, I will take a short retrospect of the
advantages and disadvantages, the pains and pleasures, of our
circumnavigation of the world.  If a person asked my advice, before
undertaking a long voyage, my answer would depend upon his possessing a
decided taste for some branch of knowledge, which could by this means
be advanced.  No doubt it is a high satisfaction to behold various
countries and the many races of mankind, but the pleasures gained at
the time do not counterbalance the evils.  It is necessary to look
forward to a harvest, however distant that may be, when some fruit will
be reaped, some good effected.

Many of the losses which must be experienced are obvious; such as that
of the society of every old friend, and of the sight of those places
with which every dearest remembrance is so intimately connected.  These
losses, however, are at the time partly relieved by the exhaustless
delight of anticipating the long wished-for day of return.  If, as
poets say, life is a dream, I am sure in a voyage these are the visions
which best serve to pass away the long night.  Other losses, although
not at first felt, tell heavily after a period: these are the want of
room, of seclusion, of rest; the jading feeling of constant hurry; the
privation of small luxuries, the loss of domestic society and even of
music and the other pleasures of imagination.  When such trifles are
mentioned, it is evident that the real grievances, excepting from
accidents, of a sea-life are at an end.  The short space of sixty years
has made an astonishing difference in the facility of distant
navigation.  Even in the time of Cook, a man who left his fireside for
such expeditions underwent severe privations. A yacht now, with every
luxury of life, can circumnavigate the globe.  Besides the vast
improvements in ships and naval resources, the whole western shores of
America are thrown open, and Australia has become the capital of a
rising continent.  How different are the circumstances to a man
shipwrecked at the present day in the Pacific, to what they were in the
time of Cook!  Since his voyage a hemisphere has been added to the
civilized world.

If a person suffer much from sea-sickness, let him weigh it heavily in
the balance.  I speak from experience: it is no trifling evil, cured in
a week.  If, on the other hand, he take pleasure in naval tactics, he
will assuredly have full scope for his taste.  But it must be borne in
mind, how large a proportion of the time, during a long voyage, is
spent on the water, as compared with the days in harbour.  And what are
the boasted glories of the illimitable ocean.  A tedious waste, a
desert of water, as the Arabian calls it.  No doubt there are some
delightful scenes.  A moonlight night, with the clear heavens and the
dark glittering sea, and the white sails filled by the soft air of a
gently blowing trade-wind, a dead calm, with the heaving surface
polished like a mirror, and all still except the occasional flapping of
the canvas. It is well once to behold a squall with its rising arch and
coming fury, or the heavy gale of wind and mountainous waves.  I
confess, however, my imagination had painted something more grand, more
terrific in the full-grown storm. It is an incomparably finer spectacle
when beheld on shore, where the waving trees, the wild flight of the
birds, the dark shadows and bright lights, the rushing of the torrents
all proclaim the strife of the unloosed elements.  At sea the albatross
and little petrel fly as if the storm were their proper sphere, the
water rises and sinks as if fulfilling its usual task, the ship alone
and its inhabitants seem the objects of wrath.  On a forlorn and
weather-beaten coast, the scene is indeed different, but the feelings
partake more of horror than of wild delight.

Let us now look at the brighter side of the past time.  The pleasure
derived from beholding the scenery and the general aspect of the
various countries we have visited, has decidedly been the most constant
and highest source of enjoyment.  It is probable that the picturesque
beauty of many parts of Europe exceeds anything which we beheld.  But
there is a growing pleasure in comparing the character of the scenery
in different countries, which to a certain degree is distinct from
merely admiring its beauty.  It depends chiefly on an acquaintance with
the individual parts of each view.  I am strongly induced to believe
that as in music, the person who understands every note will, if he
also possesses a proper taste, more thoroughly enjoy the whole, so he
who examines each part of a fine view, may also thoroughly comprehend
the full and combined effect.  Hence, a traveller should be a botanist,
for in all views plants form the chief embellishment.  Group masses of
naked rock, even in the wildest forms, and they may for a time afford a
sublime spectacle, but they will soon grow monotonous.  Paint them with
bright and varied colours, as in Northern Chile, they will become
fantastic; clothe them with vegetation, they must form a decent, if not
a beautiful picture.

When I say that the scenery of parts of Europe is probably superior to
anything which we beheld, I except, as a class by itself, that of the
intertropical zones.  The two classes cannot be compared together; but
I have already often enlarged on the grandeur of those regions.  As the
force of impressions generally depends on preconceived ideas, I may
add, that mine were taken from the vivid descriptions in the Personal
Narrative of Humboldt, which far exceed in merit anything else which I
have read.  Yet with these high-wrought ideas, my feelings were far
from partaking of a tinge of disappointment on my first and final
landing on the shores of Brazil.

Among the scenes which are deeply impressed on my mind, none exceed in
sublimity the primeval forests undefaced by the hand of man; whether
those of Brazil, where the powers of Life are predominant, or those of
Tierra del Fuego, where Death and decay prevail.  Both are temples
filled with the varied productions of the God of Nature:--no one can
stand in these solitudes unmoved, and not feel that there is more in
man than the mere breath of his body.  In calling up images of the
past, I find that the plains of Patagonia frequently cross before my
eyes; yet these plains are pronounced by all wretched and useless. They
can be described only by negative characters; without habitations,
without water, without trees, without mountains, they support merely a
few dwarf plants.  Why, then, and the case is not peculiar to myself,
have these arid wastes taken so firm a hold on my memory?  Why have not
the still more level, the greener and more fertile Pampas, which are
serviceable to mankind, produced an equal impression?  I can scarcely
analyze these feelings: but it must be partly owing to the free scope
given to the imagination.  The plains of Patagonia are boundless, for
they are scarcely passable, and hence unknown: they bear the stamp of
having lasted, as they are now, for ages, and there appears no limit to
their duration through future time.  If, as the ancients supposed, the
flat earth was surrounded by an impassable breadth of water, or by
deserts heated to an intolerable excess, who would not look at these
last boundaries to man's knowledge with deep but ill-defined sensations?

Lastly, of natural scenery, the views from lofty mountains, through
certainly in one sense not beautiful, are very memorable.  When looking
down from the highest crest of the Cordillera, the mind, undisturbed by
minute details, was filled with the stupendous dimensions of the
surrounding masses.

Of individual objects, perhaps nothing is more certain to create
astonishment than the first sight in his native haunt of a
barbarian--of man in his lowest and most savage state. One's mind
hurries back over past centuries, and then asks, could our progenitors
have been men like these?--men, whose very signs and expressions are
less intelligible to us than those of the domesticated animals; men,
who do not possess the instinct of those animals, nor yet appear to
boast of human reason, or at least of arts consequent on that reason. I
do not believe it is possible to describe or paint the difference
between savage and civilized man.  It is the difference between a wild
and tame animal: and part of the interest in beholding a savage, is the
same which would lead every one to desire to see the lion in his
desert, the tiger tearing his prey in the jungle, or the rhinoceros
wandering over the wild plains of Africa.

Among the other most remarkable spectacles which we have beheld, may be
ranked, the Southern Cross, the cloud of Magellan, and the other
constellations of the southern hemisphere--the water-spout--the glacier
leading its blue stream of ice, overhanging the sea in a bold
precipice--a lagoon-island raised by the reef-building corals--an
active volcano--and the overwhelming effects of a violent earthquake.
These latter phenomena, perhaps, possess for me a peculiar interest,
from their intimate connection with the geological structure of the
world.  The earthquake, however, must be to every one a most impressive
event: the earth, considered from our earliest childhood as the type of
solidity, has oscillated like a thin crust beneath our feet; and in
seeing the laboured works of man in a moment overthrown, we feel the
insignificance of his boasted power.

It has been said, that the love of the chase is an inherent delight in
man--a relic of an instinctive passion.  If so, I am sure the pleasure
of living in the open air, with the sky for a roof and the ground for a
table, is part of the same feeling, it is the savage returning to his
wild and native habits.  I always look back to our boat cruises, and my
land journeys, when through unfrequented countries, with an extreme
delight, which no scenes of civilization could have created.  I do not
doubt that every traveller must remember the glowing sense of happiness
which he experienced, when he first breathed in a foreign clime, where
the civilized man had seldom or never trod.

There are several other sources of enjoyment in a long voyage, which
are of a more reasonable nature.  The map of the world ceases to be a
blank; it becomes a picture full of the most varied and animated
figures.  Each part assumes its proper dimensions: continents are not
looked at in the light of islands, or islands considered as mere
specks, which are, in truth, larger than many kingdoms of Europe.
Africa, or North and South America, are well-sounding names, and easily
pronounced; but it is not until having sailed for weeks along small
portions of their shores, that one is thoroughly convinced what vast
spaces on our immense world these names imply.

From seeing the present state, it is impossible not to look forward
with high expectations to the future progress of nearly an entire
hemisphere.  The march of improvement, consequent on the introduction
of Christianity throughout the South Sea, probably stands by itself in
the records of history.  It is the more striking when we remember that
only sixty years since, Cook, whose excellent judgment none will
dispute, could foresee no prospect of a change.  Yet these changes have
now been effected by the philanthropic spirit of the British nation.

In the same quarter of the globe Australia is rising, or indeed may be
said to have risen, into a grand centre of civilization, which, at some
not very remote period, will rule as empress over the southern
hemisphere.  It is impossible for an Englishman to behold these distant
colonies, without a high pride and satisfaction.  To hoist the British
flag, seems to draw with it as a certain consequence, wealth,
prosperity, and civilization.

In conclusion, it appears to me that nothing can be more improving to a
young naturalist, than a journey in distant countries.  It both
sharpens, and partly allays that want and craving, which, as Sir J.
Herschel remarks, a man experiences although every corporeal sense be
fully satisfied.  The excitement from the novelty of objects, and the
chance of success, stimulate him to increased activity.  Moreover, as a
number of isolated facts soon become uninteresting, the habit of
comparison leads to generalization.  On the other hand, as the
traveller stays but a short time in each place, his descriptions must
generally consist of mere sketches, instead of detailed observations.
Hence arises, as I have found to my cost, a constant tendency to fill
up the wide gaps of knowledge, by inaccurate and superficial hypotheses.

But I have too deeply enjoyed the voyage, not to recommend any
naturalist, although he must not expect to be so fortunate in his
companions as I have been, to take all chances, and to start, on
travels by land if possible, if otherwise, on a long voyage.  He may
feel assured, he will meet with no difficulties or dangers, excepting
in rare cases, nearly so bad as he beforehand anticipates.  In a moral
point of view, the effect ought to be, to teach him good-humoured
patience, freedom from selfishness, the habit of acting for himself,
and of making the best of every occurrence.  In short, he ought to
partake of the characteristic qualities of most sailors.  Travelling
ought also to teach him distrust; but at the same time he will
discover, how many truly kind-hearted people there are, with whom he
never before had, or ever again will have any further communication,
who yet are ready to offer him the most disinterested assistance.

[1] After the volumes of eloquence which have poured forth on this
subject, it is dangerous even to mention the tomb.  A modern traveller,
in twelve lines, burdens the poor little island with the following
titles,--it is a grave, tomb, pyramid, cemetery, sepulchre, catacomb,
sarcophagus, minaret, and mausoleum!

[2] It deserves notice, that all the many specimens of this shell found
by me in one spot, differ as a marked variety, from another set of
specimens procured from a different spot.

[3] Beatson's St. Helena.  Introductory chapter, p. 4.

[4] Among these few insects, I was surprised to find a small Aphodius
(nov. spec.) and an Oryctes, both extremely numerous under dung.  When
the island was discovered it certainly possessed no quadruped,
excepting perhaps a mouse: it becomes, therefore, a difficult point to
ascertain, whether these stercovorous insects have since been imported
by accident, or if aborigines, on what food they formerly subsisted. On
the banks of the Plata, where, from the vast number of cattle and
horses, the fine plains of turf are richly manured, it is vain to seek
the many kinds of dung-feeding beetles, which occur so abundantly in
Europe.  I observed only an Oryctes (the insects of this genus in
Europe generally feed on decayed vegetable matter) and two species of
Phanaeus, common in such situations.  On the opposite side of the
Cordillera in Chiloe, another species of Phanaeus is exceedingly
abundant, and it buries the dung of the cattle in large earthen balls
beneath the ground.  There is reason to believe that the genus
Phanaeus, before the introduction of cattle, acted as scavengers to
man.  In Europe, beetles, which find support in the matter which has
already contributed towards the life of other and larger animals, are
so numerous that there must be considerably more than one hundred
different species.  Considering this, and observing what a quantity of
food of this kind is lost on the plains of La Plata, I imagined I saw
an instance where man had disturbed that chain, by which so many
animals are linked together in their native country.  In Van Diemen's
Land, however, I found four species of Onthophagus, two of Aphodius,
and one of a third genus, very abundantly under the dung of cows; yet
these latter animals had been then introduced only thirty-three years.
Previous to that time the kangaroo and some other small animals were
the only quadrupeds; and their dung is of a very different quality from
that of their successors introduced by man.  In England the greater
number of stercovorous beetles are confined in their appetites; that
is, they do not depend indifferently on any quadruped for the means of
subsistence.  The change, therefore, in habits which must have taken
place in Van Diemen's Land is highly remarkable.  I am indebted to the
Rev. F. W. Hope, who, I hope, will permit me to call him my master in
Entomology, for giving me the names of the foregoing insects.

[5] Monats. der Konig. Akad. d. Wiss. zu Berlin. Vom April, 1845.

[6] I have described this Bar in detail, in the Lond. and Edin. Phil.
Mag., vol. xix. (1841), p. 257.
