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Laboratory of Ornithology
33 Sapsucker Woods Read
Cornell University
ithaca, New York 14860

THE DESCENT OF MAN,

AND

SELECTION IN RELATION TO SEX.

THE

DESCENT OF MAN

AND

SELECTION IN RELATION TO SEX.

BY

0 8 get
dw

CHARLES DARWIN, M.A.,

FELLOW OF THE ROYAJ, SOCIETY. ETC.
With Allustrations.

NEW EDITION, REVISED AND AUGMENTED.

COMPLETE IN ONE VOLUME.

NEW YORK:
D. APPLETON AND COMPANY.

1896.

A

390499

Authorized Edition.

PREFACE TO TI SECOND EDITION.

Durine 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and four of the old -drawings have been replaced by better ones,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 j4ife by Mr. T. W. Wood. I must especially call
attention to sone 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 obser-
vations, 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 tha
direct and prolonged action of changed conditions of life. Some
allowance, too, must be made for occasional reversions of

vi Preface to the Second Edttion.

structure; nor must we forget what I have called “ correlated ”
growth, meaning, thereby, that various parts 0. the organisation
are in some unknown manner so connected, that when one part
varies, so do others; and if variations in the one are accu-
mulated by selection, other parts will be modified. Again, it
aas 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 con-
clusions 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, BeckennaM, KEN,
Septembor 1874.

TABLE

OF THE

PRINCIPAL ADDITIONS AND CORRECTIONS TO THE

PRESENT EDITION.

First

Edition. Present
— Edition. —_
Vou. 1
"Page Page
29 15-17 nee on the rudimentary points in the
human ear revised.
26 19 Cases of men born with hairy bodies.
27, note. | 20, note, | Mantegazza on the last molar tooth in man.
29. 23 The rudiments of a tail in man.
Bianconi on homologous structures, as ex-
32, note, | 24, note, plained by adaptation on mo avieo!
principles.
40 70 Intelligence in a baboon,
42 v1 r Sense of erie in dogs. 4
Further facts on imitation in man au
44 72.3 { animals.
47 15 Reasoning power in the lower animals,
50 80 Acquisition of experience by animals.
53 83 Power of abstraction in animals.
Power of forming concepts in relation to
58 88-9 { language. : m
Pleasure from certain sounds, colours, and
Ge 82 forms. i :
78 104 Fidelity in the elephant.
79 104 Galton on gregarivusness of cattle.
81 105-6 | Parental affection.
90. note, [ft2-113, i ; F
, vote, { note: } Persistence of enmity and hatred.
91 114 oe and strength of shame, regret, and
remorse.
94 117, note. | Suicide amongst savages.
97 120, note. | The motives of conduct.
112 28 Selection, as applied to primeval man.
122 85-6 | Resemblances between idiots aud animals,
124, note. | 39, note. | Division of the malar bone.
125, note, 36-8, note, | Supernumerary mamme and digits.
198-9 41-9 |{Further cases of muscles proper to animals
appearing in man.
Broca: average capacity of skull diminished
146 55, note, by the preservation of the inferior members

of society.

viii Table of the Principal Additions and
Fins’
Editiva, Present
—— Edition. ——
Vou. I.
Page Page .
149 57 aor on advantages to man from his hair-
lessness. f ‘
Disappearance of the tail in man and certain
1s BEY { monkeys. 5
[njurious forms of selection in civilised
169 134-5 { ica
Indolence of man, when free from a struggle
180 sa { for existence.
193 151 ya Sens himself from rain with his
208. note. | 161, note | Hermaphroditism in fish.
209 163 Rudimentary mamme in male mammals.
Changed conditions lessen fertility and cause
ea 188-190 { ill-health amongst savages.
245 195-6 arronag of skin a protection against the
Note by Professor Huxl-y on the develop-
#8 se as { ment of the brain in man and apes.
. Special organs of male purasitic worms for
a Zea) { holding the female.
Greater variability of male than f-male;
275-6 224-5 direct action of the environment in causing
differences between the sexes.
Period of development of protuberances
290 235 on birds’ hcads determines their trans-
mission to one or both sexes.
301 243-4 | Causes of excess of male births.
314 254 Proportion of the sexes in the bee tamily.
315 255-6 fExcess of males perhaps sometimes deter-
i {mined by selection.
B27 264 Bright colours of lowly organised animals.
338 272 Sexual selection amongst spiders.
329 273 Cause of smallness of male spiders.
345 277 Use of phosphorescence of tle glow-worm.
349 280 The humming noises of flies.
350 281 Use of bright coluurs to Hemiptera (bugs).
351 282 Musical apparatus of Homoptera.
S54 ; 284-5 |(Development of stridulating apparatus in
359 288, note. Orthoptera.
366 292-3 he Miiller on sexual differences of
387 308 Sounds produced by moths.
397 315 Display of beauty by butterflies.
401 ; 319 aces buttertlies, taking the more active
i part in courtship, brighter than their males,
412 | 304-5 ! {peal cases of mimicry in butterflies and
F ‘ause of bright and diversified colours of
417 cia - caterpillars,

Corrections to the Present Edition. ix

First
Kdition. Present
—_— dition. <=
Vou. LU.
Page Page
2 331 Brushi-like scales of male Mallotus.
14 341 ee facts on courtship of fishes, and the
spawning of Macropus.
23 347 Dufossé on the sounds made by fishes.
26 349 Belt on a frog protected by bright colouring,
30 352 Further facts on mental powers of snakes
32 353, Sounds produced by snakes; the rattlesnake.
36 357 Combats of Chameleons,
72 383 Marshall on protuberances on birds’ heads.
Further facts on display by the Argus
at se { pheazant.
108 411 Attachment between paired birds.
118 417 Female pigeon rejecting certsin males.
120 419 ao birds not finding partners, in a state
of nature.
124 423 | Direct action of climate on birds’ colours,
147-150! 438-441 lagen’ facts on the ocelli in the Argus
pheasant.
152 443 Display by humming-birds in courtship.
157 446 Cases with pigeons of coluur transmitted to
{ one sex alone.
Taste for the beautiful permament enough
232 495-6 to allow of sexual selection with the lower
animals. i i
= Horns of sheep originally » masculine
a ss { character. re
248 506 Castration affecting horns of animals,
256 513-514 Prong-horned variety of Cervus virginianus.
260 516 Nene aa sizes of male and feniale whales and
seals.
266 521 Absence of tusks in male miocene pigs.
286 534 Dobson on sexual differences of bats.
299 542-3 | Reeks on advantage from peculiar colouring.
316 556 Difference of complexion i in men and women
o of an African tribe.
337 Sr Speech subsequent to sing’ng.
. . Schopenhauer on importanee of courtship te
356 580 | { mankind. ,
Revision of dliseussion on communal marringes
B59 ef seg. | 588 ef seq. { and promiscuity, :
‘Power of choice of woman in marriage,
ats as { amongst savages.
380 603 fonpeoidinnal habit of plucking out hairs

may produce an inherited effcet.

CONTENTS.

LsvropucTiay ‘i - ‘ ‘ . ‘ Pages 14

un

PART I.
THE DESCENT OR ORIGIN OF MAN,

a CHAPTER I.

Tue Eviprncre or tHe Descent or Man rrom some Lower Form.
PAGR
Nature of the evidence bearing on the origin of man—Homologous
structures in man and the lower animals—Miscellaneous points
of correspondence — Develupment — Rudimentary structures,
muscles, sense-organs, hair, bones, reproductive organs, &c.—
The bearing of these three great clisses of facts on the origin of

man . P ? ‘ i i ‘ 4 i 5
CHAPTER II.
Oy Tar Manner or DEVELOPMENT OF Man FROM somE LOWER
Form,

Variability of body and mind in man—Inheritance—Causcs of
variability—Laws of variation the same in man as in the lower
animals—Direct action of the conditions of life—Ettects of the
increased use and disuse of parts—Arrested development—Re-
version — Correlated variation—Rate of Increase —Checks to
inerease—Natural selection—Man the most dominant animal in .
the world—Importauce of his corporeal structure—The causes
which have led to bis becoming erect—Consequent changes of
structure—Decrease in size of the canine teeth—Increased size
and altered shape of the skull—Nakedness—A bsence of a tail—
Defenceless condition of man E ‘ 26

CHAPTER IT.

ComPanisoX or THE Menta Powrrs or Many anp THE Lowen
ANIMALS,

The difference in mental power between the highest ape and the
lowest savage, immense—Certain instincts in common—The
emotions‘—Curiosity—Imitation—A ttention — Memory—Imagi-
nation-- Reason—Progressive improvement—Tools and weapon-

xii Contents.

used by snimals—Abatraction, Self-consciousness—Language
—BSense of beauty—Belief in God, spiritual ageucies, super-
stitimsa . : : . : . : .

CHAPTER IV.

PAGE

65

COMPARISON oF THE MENTAL PowrerRs OF MAN AND THE LOWEN

ANIMALS— continued.

fhe moral sense—Fundamental proposition—The qualities of
social animals—Orizin of sociability—Struggle between opposed
instincts—Man a social animal—The more enduring social in-
stincts conqucr other less persistent instincts—The social virtues
slone regarded by savayes—The self-reyarding virtues acquired
ata later stage of development—The importance of the judg-
ment of the members of the same community on conduet—
Transmission of moral tendencies—Summuary

CHAPTER V.

On THE DEVELOPMENT OF THE INTELLECTUAL AND MoRAuL
FactLtigs purine Primevat AND CIvILIsepD Times.

Advancement of the intellectual powers through natural selec-
tion—Importance of imitation—Social and moral faculties—
Their development within the limits of the same tribe—Natural
selection as afftcting civilised nations—Evidence that civiliscd
uations were once barbarous : : ‘ 7 .

CHAPTER VI.
On THE AFFINITIES AND GENEALOGY oF Man.

Posit‘on of man in the animal series—The natural system genea-
logical—Adaptive characters of slight value—Varions small
points of resemblance between man and the Quadrumana—
Rank of man in the natural system—Birthplace and antiquity
of man—Absence of fossil connccting-links—Lower stages in
the genealogy of man, as inferred, firstly from his affinities and
secondly from his structure—Harly androgynous condition of
the Verte brata—Conclusion

CHAPTER VIL.

On THE Races or May.

The nature and value of specific characters—Application to the
raecs of man—Arguments tn favour of, and opposed to, ranking
the so-called races of man as distinet species—Snb-species—
Monogenists and polygenists--Convergence of character -—

97

127

Contents. xt

PAGR
N uweroug 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—Exch ruce not descended from a single
yair—The extinction of races—The formation of races—The
effects of crossing—Slight influence of the direct uction of the
conditions of life—Slight or no influence of natural sclection—
Sexual selection . . . . : 3 . 164

PART II.
SEXUAL SELECTION,
— ees

CHAPTER VIII.
Putxcrptes or Srxvuat SELECTION,

Secondary sexual characters—Sexual selection—Manner of action
—Excess of males— Polygamy——The wale alone generally
modified through sexual selection—Eagerness of the mule—
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 inheri-
tance—Cuures why one sex and the young are not modified
through sexual selection—Supplement on the proportional num-
bers of the two sexes throughout the animal kingdom—The
proportion of the sexes in relation tu nutural selection . . 207

CHAPTER IX.

Seconpary SexvuaL CHARACTERS IN THE Lowen CLASSES OF
THE ANIMAL KinGpom.

These « haracters absent in the lowest classes—Brilliant colours—
Mollusca—Annelids—Crustacea, secondary sexual characters
strongly developed; dimorphism; colour; characters not ac-
quired before maturity—Spiders, sexual colours of; stridulation
by the males—Myriapoda . . : c F - 260

CHAPTER X.

Srconpary SEXUAL CHARACTERS OF INSECTS.

Diversified structures possessed by the males for seizing the
females—Differences between the sexes, of which the mean-
ing is not understood—Difference in size between the sexes—
Thysanuru—Dip era—Hemipt: ra—Homoptcra, musical powers

xiv Contents.

PAGE
possessed by the males alone—Orthoptera, musical instruments
of the males, much diversified in structure; pugnacity ; colours—
Neuroptera sexual differences in colour—Hymenoptera, pug-
nacity aud colours—Covleoptera, colours; furnished with great
horns, apparently as an ornament; battles; stridulating organa
g erally common te both sexcs A . . . 274

CHAPTER XI.

[nsgors, continued—Orprr LepiDorTEra,
(BUTTERFLIES AND MOTHS.)

Courtship of batterflies—Battles—Ticking noise—Coiours 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—Dis)lay—Pereeptive
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—Briglit
colours of caterpillars—Summary and concluding remarks on
the secondary sexual characters of insects—Birds and insects
compared 5 4 é q r ‘i Fi 307

CHAPTER XII.

SeconpDary SexvuaL Cuaracturs or Fisues, AMPHIBIANS, AND
REPTILES.

¥isHEs: Courtship and battles of the males—Larger size of the
females—Males, bright colours and ornamental appendages;
other strange characters—Colours and appenilages acquired by
the males during the breeding-season alone—Fishes with both
sexes brilliantly coloured—Protective colours—The less con-
spicuous 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. Ampuipians: Differences in
structure and colour between the sexes—Vocal organs. Rup-
TILES: 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 . . 330

CHAPTER XIII.

Srconpary Sexual CuHaracters or Birps.

Sexual differences — Law of battle—Special weapons — Voenl
orgaig—lIustrumental music—Love-antics and daneces—Deco-
tions, permanent and seasonal—Donble and single annual
moulits—D splay of ornaments by the males ‘ ? 358

Contents. XV

CHAPTER XIV.

Binps—continwed,
PAQE
Choice exerted by the female—Length of courtship—Unpaired

birds—Mentai qualities and taste fur the beautiful—Preference
or antipathy shewn by the female for particular males—Vari-
ability of birds—Variations sometimes abrupt—Laws of varia-
tion—Formation of ocelli—Gradations of Uhanaehor Sse of
Peacuck, Argus pheasant, and Urosticte . . . 404

CHAPTER XV.
Birps—continued,

Discussion as to why the males alone of some species, and both
sexes of others are brightly coloured—Ono sexually-limited
inheritance, as applied to various structures and to brigltly-
coloured plumaye—Nidification in relation to colour—Loss of
nuptial plamage during the winter. : : . 444

CHAPTER XVI.
Birps—concluded.

{be immature plumage in relation to the character of the plumage
in both sexes when adult—Six classes of cases—Sexual differ-
ences between the males of closely-allied or representative
species—The female assuming the characters of the male—
Plumage of the young in relation to thg summer and winter
plumage of the adults—On the increase of beauty in the birds
of the world — Protective colouring —Conspicuously-coloured
tee oely appreciated—Summary of the four chapters on
birds é 5 2 . . . . . 463

CHAPTER XVII.
Szconpary SexuaL CHARACTERS OF MAMMALS.

Lhe law of battle—Special weapons, confined to the males—Cause
of absence of weapons in the female—Weapons common to buth
sexes, yet primarily acquired by the male—Other uses of such
wveapons—Their high importance—Greater size of the male—
Means of defence—On the preference shewn by either sex in the
pairing of quadrupeds ‘ ‘ P . A i 50u

CHAPTER XVIII.

Sxconpary SExuAL CHARACTERS OF MammMaLs—eontinued,

Voice—Remarkable sexual peculiarities in scals—Odour—D.-velop-
mnt of the hair--Colour of the hair and skin—Anomalous

Kvi Contents.

PAGS
ease of the female beivg 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
8,)Uis and stripes in adult quadrupeds—On the colours and orna-
ments of the Quadrumana—Summary . .

a
ee
a

PART III.

SEXUAL SELECTION IN RELATION TO MAN,
AND CONCLUSION.

+1

CHAPTER XIX.
Seconpary SexuaL CHARAcrers or Man.

Differences between man and woman—Causes of such differences,
and of certain chayacters 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 orcaments—Their ideas of beauty in woman
—The teudency to exaggerate each natural peculiarity 3 556

CHAPTER XX,
Sxeconpaxy SexuaL CHaRraAcTERS OF Man—continued.

On the effects of the continued selection of women according to a
different stundard of beauty in each race—On the vauses 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 man-
kind—On the women in savage tribes having some power to
choose their hushands—Absence of hair on tle body, and
development of the beard—Colour of the skin—Summary . 585

CHAPTER XXTI.

GerneraL StmMMARY AND CONCLUSION.

{fain conclusion that man is descended from some lower form—
Manner of deyelopment—Genealogy of man—Intellectual aud
moral faculties—Sexual selection—Concluding remarks. 60F

Innes : . < ‘ . .

THE DESCENT OF MAN;

AND

SELECTION IN RELATION TO SEX.

INTRODUCTION.

Tue nature of the following work will be best understood by a
brief account of how it came to be written. During many years
[ cullected notes on the origin or descent of man, without any
inteation 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 création indépendante et de
“toutes piéces, des espéces,” 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. ‘Fhe 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

2

2 Introduction.

others who are not sciontific, I have been led to put togethers
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
dzrived from the nature of the aftinities 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 rudi-
mentary 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 discussed 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 indis-
pensable 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 anthropomor-
phous 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

Introduction, 3

any degree new. Jamarck 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, &c.,! and especially by Hackel. This
last naturalist, besides his great work, ‘Generelle Morphologie’
(1866), has recently (1868, with a second edit. in 1870), pub-
lished his ‘ Natiirliche Schépfungsgeschichte, 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. Hackel’s writings, I give his autho-
rity 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 bighly probable that
sexual selection has played an important part in differentiating
the races of man; but in my ‘ Origin of Species’ (first edition, p.
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 Consequently the second
part of the present work, treating of sexual selection, has ex-
tended to an inordinate length, compared with the first part;
but this could rot be avoided.

T 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

.

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 iiber die Darwin’sche
Theorie:’ zweite Auflage, 1868, von
Dr. L, Biichner; translated into
French under the title ‘Conferences
sur la Theorie Darwinienne,’ 1869.
‘Der Mensch, im Lichte der Dar-
win’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, 1567, p. 81) a very
curious paper on rudimentary cha-
racters, as bearing on the origin ot
Tan. 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.”

2 Prof. Hickel was the only
author who, at the time when this
work first appeared, had discussed
the subject of sexual se]<ction, 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.

4 Introduction.

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
sams manner by the different races of man. But owing to tha
wwngth of the present work, I have thought it better to reserve
fay essay for separate publication.

Part I,
THE DESCENT OR ORIGIN OF MAN.

CHAPTER I.

Tue EvIDENOS oF THE Descent oF MAN FROM SOME
Lower Form.

Niture 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, sénse-
organs, hair, bones, reproductive organs, &c.—The bearing of these three
great classes of facts on the origin of man.

Hx who wishes to decide whether man is the modified descendant
of some pre-existing fori, 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, &c.? Is man subject to similar mal-
conformations, the result of arrested development, of reduplication
of parts, &c., and does he display in any of his anomalies rever-
sion 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 ta
occasional severe struggles for existence; and consequently tk

6 The Descent of Man. Panr 1

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 lowcr 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 shows 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 Botily Structure of Mun.—It is notorious that man is
constructed on the same general type or model as other mam-
mals, All the bones in his skeleton can be compared with
corresponding bones sr monkey, bal. ox seal. So it is with his
muscles, 9érvés, 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,! 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? remarks:
“Les différences réelles qui existent entre l’encéphale de
“ Phomme et celui des singes supérieurs, sont bien minimes. II
“ne faut pas se faire d’illusions a cet égard. L’homme est bien
“plus prés des singes anthropomorphes par les caractéres
“anatomiques de son cerveau que ceux-ci ne le sont nov-
“seulement des autres mammiféres, mais méme 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 com-

1 ‘Grosshirnwindungen des Men- in the Preface to this edition.
schen,’ 1868,s.96. The conclusions ? «Leg. sur la Phys.’ 1866, p. 890,
of this author, as well as those of as quoted by M. Dally, ‘ L’Ordre des
Gratiolet and Aeby, concerning the Primates et le Transformisme,’ 1868,
brain, will be discussed by Prof. p. 29,

Huxley in the Appendix alluded te

Snap. I. Flomological Structures, 7

municate to them, certain diseases, as hydrophobia, variola, the
glanders, syphilis, cholera, herpes, &c.;* and this fact proves the
close similarity* 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,’ who carefully
observed for a long time the Cebus Azare 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 spirituous liquors: they will also, as I
have myself seen, smoke tobacco with pleasure.’ 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.’ 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

3 Dr. W. Lauder Lindsay has

tinct fluids by the same chemical
treated this subject at some length

reagent.

in the ‘Journal of Mental Science,’
July 1871;’and in the ‘Edinburgh
Veterinary Review,’ July 1858.

4+ A Rev.ewer has criticised
(‘British Quarterly Review,’ Oct.
Ist, 1871, p. 472) what 1 have here
gaid with much severity and con-
tempt; 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 pro-
ducing the same result, or one
closely similar, in two distinct ani-
mals, and the testing of two dis-

5 *Naturgeschichte der Siuge-
thiere von Paraguay,’ 1830, ». 50,

® The same tastes are common to
some animals much lower in the
scale. Mr, A. Nicols informs me
that he kept in Queensland, in Avs-
tralia, 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.

7 Brehm, ‘Thierleben,’ B. i. 1864,
s. 75, 86. On the Ateles, s. 105,
For other analc gous statements, see
s. 25, 107.

8 The Descent of Man. , Paar I,

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.*® Mau
is subject, like other mammals, birds, and even insects,® 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 embryonio
period, occasionally possess some power of regeneration, as in
the lowest animals.’?

The whole process of that most important function, the
reproduction of the species, is strikingly the same in all mam-
mais, from the first act of courtship by the male," to the birth
and nurturing of the young. Monkeys are born in almost as
helpiess 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.” 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. Man differs from woman in size, bodily strength,
hairiness, &c., as well as in mind, in the same manner as do the

® Dr. W. Lauder Lindsay, ‘ Edin-
burgh Vet. Review,’ July 1858,
. 13.

r ® 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. p. 305, has seen a dog
suffering from tertian ague. Here-
ter I shall return to this subject.

10 [ have given the evidence on
his head in my ‘ Variation of Ani-
aals and Plants under Domestica-
jon,’ vol, ii. p. 15, and more could
vé added.

“Mares e diversis generibus
“ Quadrumanorum sine dubio di-
“ gnoscunt feminas humanas a ma-
“yibus. Primum, credo, odoratu,
“ postea aspectu. Mr. Youatt, qui
“diu in Hortis Zoologicis (Besti-
* ariis) medivus animalium erat,
*“virin rebu' owservandis cautus et

“ sagax, hoc mihi certissime pro-
“ bavit, et curatores ejusdem loci et
“alii e ministris confirmaverurt.
“Sir Andrew Smith et Brehm no-
“tabant idem in Cynocephalo. Il-
“ lustrissimus Cuvier etiam narrat
“multa de hac re, qua ut opinor,
“nihil turpius potest indicari inter
*“ omnia hominibus et Quadrumania
“communia. Narrat enim Cyno-
“ cephalum quendam in furorem in-
“cidere aspectu feminarum ali-
“quarum, sed nequaquam accendi
“tanto furore ab omnibus. Sem-
“per eligebat juniores, et dignose
“ cebat in turba, et advocabat voce
“ gestiique.”

2 This remark is made with re-
spect to Cynocephalus and the an-
thropomorphous apes by Geoffroy
Saint-Hilaire and F. Cuvier, ‘ Hist.
Nat. des Mammiferes,’ tom, i. 1824,

'S Huxley, ‘Man’s Place in Nae
ture,’ 1863, p. 34.

Unap. 1 Homological Structures.

9
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 ex-
tremely close.

Embryonic Development——Man is developed from an ovules,
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
branchis which are not present in the higher vertebrata, though
the slits on the sides of the neck still remain (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,* “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 copicd from two
works of undoubted accuracy.’

After the foregoing statements made by such uigh autho-
rities, 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

14 ¢Man’s Place in Nature,’ 1863,
p 67.

i} The human embryo (upper
fig.) is from Ecker, ‘Icones Phys.,”
1851-1859, tab. xxx. fig. 2. This
embryo was ten lines in length, so
tnat the drawing is much magnified.
The embryo of the dog is from
Bisenoff, ‘ Entwicklungsgeschichte
des Hunile-Eies,’ 1845, tab. xi. fig.
42 B This drawing is tive times

magnified, the embryo being twenty-
five days old. The internal viscera
have been omitted, and the uterine ap
pendages in both drawings removed
I was directed to these figures Ly
Prof. Huxley, from whose work,
‘Man's Place in Nature,’ the idea of
giving them was taken. Hickel has
also given analogous drawings in his
‘ Schépfungsgeschichte.’

10 The Descent of Man. Part 1,

Fig. 1. Upper figure human embryo, from Fcker. Lower figure that of a dog,

trom Bischoff.
a. Fore-brain, cerebral hemispheres, &e. a. Second visceral arch.
b. Mid-brain, corpora quadrigemina. H. Vertebral columns and muscles
ec. Hind-b ain, cereb um, medulla ob- process of development.
fongata. i Anterior ere
da, Kye. K. Posterior t extremities.
e, Ear. L. Tail or os cocryx.

f, First visceral arch,

Snap. I. Rudiments. "

like a true tail, “extending considcrably beyond the rudi-
“mentary legs.”'® Inthe embryos of all air-breathing vertebrates,
certain glands, called the corpora Wolffiana, correspond with,
and act like the kidneys of mature fishes.” 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." The breat toe, as Prof. Owen remarks,*
“which forms the fulerum 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” 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 per-
“ manent condition of this part in the quadrumana.” I will
conclude with a quotation from Huxley,’ 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 animais
“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 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 abso-
lutely useless, such as the mamme 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

'6 Prof. Wyman in ‘Proc. of
American Acad. of Sciences,’ vol. iv.
1860, p. 17.

17 Owen, ‘Anatomy of Verte-
brates,’ vol. i. p. 533.

18 ‘Die Grosshirnwinduuzen des
Menschen,’ 1868, s. 95.

49 ¢ Anatomy of Vertebrates,’ vol.
di. p. 553.

2 « Proc. Soc. Nat. Hist.’ Boston,
1868, vol. ix. p. 185.

21 < Man’s Place in Nature,’ p. 65,

22 I had written a rough copy of
this chapter before reading a value
able paper, “Caratteri rudimentali
in ordine all’ origine del uomo”
(‘Annuario della Soc. d. Nat.,’? Mo-
dena, 1867, p. 81), by G. Canestrini,
to which paper I am considerably
indebted. Hackel has given admir-
able discussions on this whole sub-
ject, under the title of Dysteleology,
in his ‘Generelle Morphologie’ and
‘ Schépfungsgeschichta.”

Part L

12 The Descent of Mun.

conditions whick now exist. Organs in this lalter 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 compensa-
tion 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,” 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, I need
here say no more on this head.
Rudiments of various muscles have been observed in many
parts of the human body;” and not a few muscles, which are

23 Some good criticisms on this
subject have been given by Messrs.
Murie and Mivart, in ‘ Transact.
Zoolog. Soc.’ 1869, vol. vii. p. 92.

24 ¢ Variation of Animals and
Pleats under Domestication,’ vol. ii.
pp. 317 and 397. See also ‘ Origin
of Species,’ 5th edit. p. 535,

25 For instance M. Richard (‘ An-
pales des Sciences Nat.’ 3rd series,

Zoolog. 1852, tom. xviii. p. 13) de-
scribes and figures rudiments of
what he calls the “ muscle pédieux
de la main,” which he says is some-
times “infiniment petit.” Another
muscie, called “le tibial postérieur,”
is geuerally quite absent in the
hana, dut appears from time to time
in a more or less rudimentary cow
@ition.

Cnap. I. Rudiments, 13

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 thecpanniculus 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
taised. 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 axille, near the scapuls,
&e., all of which must be referred to the system of the panni-
culus, He has also shewn” that the musculus sternalis or sternalis
brutorum, which is not an extension of the rectus ubdominalis,
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 super-
ficial 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 hecame 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.”

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

28 Prof. W. Turner, ‘Proc. Royal Emotions in Man and Animals;

Soc. Edinburgh,’ 1866-67, p. 65. 1872, p. 144,
21 See my ‘Expression of the

14 The Descent of Man. Part 1

of the zanniculus; 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; 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. Tle 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, &c.) 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,” 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.*® Iam 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
Tam not satisfied with this view, that owing to their arboreal
habits and great strength they were but little exposed to danger,
aud 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, ard 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 com-
pensated by the freedom with which they can move the head in

8 Canestrini quotes Hyrtl. (‘An- lately been experimenting on the
aunvie della Soc. dei Natucalisti,’ function of the shell of the ear,
Modena, 1867, p. 97) to the same and has come to nearly the same
effect. conclusion as that given here.

24 ¢The Diseases -f the Ear,’ by 30 Prof. A. Macalister, ‘ Apnals
J. Toynbee, F.R.S., 1860, p. 12. and Mag. of Nat. History,’ vol. vii,
A distinguished physiologist, Prof. 1871, p. 342.

Prever, informs me that he had

Cnay. I. Rudiments. 15

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 ;”* and, as I hear
from Prof. Preyer, it is not rarely absent in the negro.

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 signie
ficance. 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 sub-
sequently more carefully those of man. The peculiarity consists
ina 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 ob-
served a case in one of the spider-
monkeys (Ateles beelzebuth) in our
Zoological Gardens; and Dr. E. Ray _
Lankester informs me of another case "83, Homan yet yieincns
in a chimpanzee in the gardens at a. The projecting point,
Hamburg. The helix obviously con-
sists of the extreme margin of the ear folded inwards: and
this folding appears to be ia 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,” 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 io

31 Mr. St. George Mivart, ‘Ele- Lemuroidea, in Messrs. Murie and
mentary Anatomy,’ 1873, p. 396. Mivart’s excellent paper in ‘Tran-

32 See also some remarks, and sact. Zoolog. Soe.’ vol. vii. 1869, pp.
the drawings of the ears of the 6 and 90.

16 The Descent of Man. Pant I

be their origin in many cases, On the other hand, Prof. L. Meyer,
in an able paper recently published,* 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,
us 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 micro-
cephalous 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. Never-
theless 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. ‘wo 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* of the ear of a monkey, the
Cynopithecus niger, and says that their outlines are closcly
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. 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
toa point projecting inwards. On the whole, it still seems ta
38 Ueber das Dar-wir “ache Snitzohr, ** <The Expression of the Emo-
4rchiv fir Path, anat. und Phys. _ tions,’ p. 136,
2871, p. 485.

Cap, I. Rudiments. 17

me probable that the points in question are in some cases, both
in man and apes, vestiges of a former condition.

Fig 3 Feetus of an Orang. ! xact copy of a photograpL, shewing the torts A
the ear at this early age.

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 mam-
malian 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 cxists, as is
admitted by all anatomists, as a mere rudiment, called the
semilunar fold.®

The sense of smell is of the highest importance to the grater
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

38 Miiller’s ‘Elements of Physi- Knox, ‘Great Artists and Anato-
ology,’ Eng. translat., 1842, vol. ii. mists,’ p. 106. This rudiment ap-
p. 1117. Owen,‘ Anatomy of Verte- parently is somewhat larger in
brates,’ vol. iii. p. 260; ibid, on Negroes and Australians than in
the Walrus, ‘Proce. Zoolog. Soc.? Europeans, see Carl Vogt, ‘ Lectures
November 8th, 1854. See also R. on Man,’ Eng. translat. p, 129.

3

18 The Descent of Man.

Parr I,

much more highly developed than iz the white and civilised
taces.6 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 at-
tended to the subject. Those who believe in the principle
of gradual evolution, will not readily admit that the sense ot
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 con-
tinually 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,” 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. Buta 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
hear thick tufts of hair** 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, oceasion-

30 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,’ &c., tom. i.
1872, p. 91) asserts that he re-
peatedly made experiments, and
proved that Negroes and Indians
could recognise persons in the dark
by their odour. Dr. W. Ogle hag
made some curious observations or
the connection betwcen the power
ef smell and the colouring matter
n€ the mucots meinbrane 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 Tran-
sactions,’ London, vol. liii, 1870,
p 276.

37 <The Physiology and Patholo
of Mind,’ 2nd edit. 1868, p. 134, =

3° Eschricht, Ueber die Richtung
der Haare am menschlichen Kérper,
‘Miiller’s Archiv fiir Anat. und Phys.'
1837, s. 47. I shall often have te
refer to this very curious paper.

Cuap. I. Rudiments. 1g

ally become developed into “thickset, long, and rather coarse
* dark hairs,” when abnormally nourished near old-standing
inflamed surfaces.”

Tam 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 louger than that on the head. A moustache
of this kind was observed by Eschricht® 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, 1s 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 loweranimals. As
this can hardly be an accidental coincidence, the woolly cover-
sng of the foetus probably represents the first permanent coat of
hair in those mammals which are born hairy. Three or four
eases have been recortled 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 abnor
mal condition of the teeth." Prof. Alex. Brandt informs me tha:
he has compared the hair from the face of a man thus chara
terised, aged thirty-five, with the lanugo of a foetus, and finds j
yuite similar in texture; therefore, as he remarks, the case ma,
be attributed to an arrest of development in the hair, togeth
with its continued growth. Many delicate children, as I ha

Paget, ‘Lectures on Surgical has recently sent me an additional
Pathology,’ 1853, vol. i. p. 71. case of a father and son, born in
40 Kschricht, ibid. s. 40, 47. Russia, with these peculiarities. 1]
\ See my ‘Variation of Animals have received drawings of both from
and Plants under Domestication,’ Paris.
vol. ii, p. 327, Prof. Alex. Brandt

20 The Descent of Man. Past |

been assured by a surgeon to a hospital for children, have their
backs covered by rather long silky hairs; and such cases pro-
bably come under the same head:

It appears as if the posterior molar or wisdom-teeth were
tending to become rudimentary in the more civilisud races of
man. ‘These teeth are rather smaller than the other molars, as
is likewise the case with the corresponding teeth in the chim-
panzee 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.“ 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
tho other molars in size, less than in the Caucasian races.“
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,** and this shortening may,
I presume, be attributed to civilised men habitually feeding on
soft, cooked food, and thus using their jaws less. Iam informed
by Mr. Brace that it is becoming quite a common practice in the
Tnited States to remove some of the molar teeth of children, ay
the jaw does not grow large enough for the perfect development
of the normal number.*

With respect to the alimentary canal, I have met with an
account of only a single rudiment, namely the vermiform append-
age of the cecum. The cecum is a branch or diverticulum of

6 intestine, ing 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.
It is sometimes produced into a long gradually-tapering point,
and is sometimes constricted in parts. It appears as if, in con-
sequence of changed diet or habits, the cacum had become much

42 Dr. Webb, ‘Teeth in Man and
the Anthropoid Apes,’ as quoted by
Dr. C. Carter Blake in ‘ Anthropo-
logical Review,’ July 1867, p. 299.

“3 Owen, ‘Anatomy of Verte-
brates,’ vol iii. pp. 320, 321, and
325.

44 ¢On the Primitive Form. of the
Skull,’ Eng. translat. in ‘ Anthropo-
logical Review,’ Oct. 1868, p. 426.

48 Prof Mrrteg-zza write: to me

from Florence, that he has lately
been studying the last molar teeth
in the diiferent 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 o1
elimination.

4° Owen, ‘Anatomy of Verte
brates,’ vol. iii. pp. 416, 434, 441.

Cuar., I. Rudiments. 21

shortened in various animals, the vermiform appendage being
left. as a rudiment of the shortened part. That this appendage
is a cudiment, we may infer from its small size, and from the
evidence which Prof. Canestrini*’ has collected of its variability
in man. It is occasionally quite absent, or again is largely
devaloped. 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
cecum, 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 inflam-
mation.

In some of the lower Quadrumana, in the Lemuride and
Carnivora, as well as in many marsupials, there is a passage near
the lower end of the humerus, called the supra-condyloid fora-
men, 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,*® who has
closely attended to the subject, has now shewn thut this
peculiarity is sometimes inherited, as it has occurred in a father,
and in no less than four out of his seven children. When pre-
sent, the great nerve invariably passes through it; and this
clearly indicates that it is the homologue and rudiment of the
supra-condyloid foramen ofthe 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,

47 ¢Annuario della Soc. d. Nat.? Feb. 15, 1873, and another im-

Modena, 1867, p. 94.

48M. C. Martins (“De PUnité
Organique,” in ‘Revue des Deux
Mondes,’ June 15, 1862, p. 16), and
Hackel (¢ Generelle Morphologie,’
B. ii. s. 278), have both remarked
on the singular fact of this rudi-
ment sometimes causing death.

49 With respect to inheritance,
see Dr. Struthers in the ‘ Lancet,’

portant 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 im-
portant memoir on this process by
Dr. Gruber, in the ‘Bulletin de
VAcad. Imp. de St. Pétersbourg,
tom. xii. 1807, p. 448.

Darr t

22 The Descent of Atan.

occasionally present in man, which may be called the inter-
condyloid. This occurs, but not constantly, in various anthro-
poid and other apes,” 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 thar
recently. Mr. Dusk” 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 ‘Cimetiére 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 extraordi-
“ nary 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 Vauréal. Nor should
“it be left unnoticed that M. Pruner-Bey states that this con-
“ dition 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 vertebra
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, to form a small external rudiment of a
tail. The os coceyx is short, usually including only four
vertebree, all anchylosed together: and these are in a rudi-

*9 Mr. St. George Mivart, ‘ Trans-
act. Phil. Soc.’ 1867, p. 310.

31 “On the Caves of Gibraltar,”
‘Transact. Internat. Congress of
Prehist. Arch.’ Third Session, 1869,
p. 159. Prof. Wyman has lately
shewn (Fourth Annual Report, Pea-
body Museum, 1871, p. 20), that this
perforation is present in thirty-one
per cent. of some numan remains
from ancient mounds in the Western
United States, ard m Florida. It
frequently occurs in tle negro.

52 Quatrefages has lately collected
the evidence on this subject. ‘Revue
des Cours Scientifiques,’ 1867-1868,
p- 625. In 1840 Fleischmann ex-
hibited a human fetus bearing a
free tail, which, as is not always the
case, included vertebral bodies; and
tnis tail was critically examined by
the many anatomists present at the
ineeting of naturalists at Erlangen
(see Marshall in Niederlindischen
Archiv fiir Zoologie, December 187 L}

Uaap. I. Rudiments. 23

meutary condition, for they consist, with the exception of the
basal one, of the centrum alone.’® 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 go
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 struc-
ture (the filum terminul:) 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 in-
debted to Prof. Turner, shews how closely the os coccyx corre-
sponds with the true tail in the lower animals: Luschka has
recently discovcred 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
ot which they found a similarly convoluted body, though not at
the extremity.

The reproductive system offers various rudimentary struc-
tures; 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 inheri-
tance, 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 mamme
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

63 Gwen, ‘On the Nature of Limbs,’ 1849, p. 114,

24 The Descent of Man, Parr 1,

measles. The vesicwla prostutica, which has been observed in
many male mamiais;istow universally acknowledged to be
the homologue of the female uterus, together with the con-
nected 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.** Some other rudimentary structures belonging to
the reproductive system might have been here adduced.»

‘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 Specics,’
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, d&c., is utterly
inexplicable.** 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

54 Leuckart, in Todd’s ‘Cyclop.
of Anat.’ 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.

55 See, on this subject, Owen,
‘Anatomy of Vertebrates,’ vol. iii.
pp. 675, 676, 706.

$6 Prof. Bianconi, in a recently
published work, illustrated by ad-
mirable engravings (‘La Theorie
Darwinienne et la création dite in-
dependante,’ 1874), endeavours to
show that homological structures, in
the above and other cases, can be
fully explained on mechanical prin-
ciples, in accordance with their uses.
No one has shewn so well, how ad-
mirably such structures are adapted
for their final purvose; and this
adaptation can, as I believe, be
explained through natural selection.
In considering the wing of a bat, he
brings forward (p. 21S) what appears
lo me (to- use Auguste Comte’s

words) 4 mere metaphysical prin-
ciple, 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
mamme 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 natural-
ists seems to me left unshaken,
that homological structures are in-
explicable on the principle ot mere
adaptation,

Onap. I. Rudiments. 25

variations supervening at a rather late embryonic period, and
being inherited at a corresponding period, how itis 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 viven of the marvellous fact
that the embryos of a man, dog, seal, hat, reptile, &c., 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 superfiuous part, aided by the other means previously in-
dicated.

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 geolo-
gical 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 8 s9paraie act of creation.

26 The Descent of Man, Pant L

CHAPTER II.

Ox THK MANSER OF DEVELOPMENT oF MAN FROM SOME
Lower Form.

Variability of body and mind in man—Inheritanc e—-Causes of variability
—Laws of variation the same in man as in the lower animals—Direct
action of the conditions of lite—Effects of the increased use and disuse
of parts—Arrested development—Reversion—Oorrelated 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—lIncreased size and
altered shape of the skull—Nakedness—Absence of a tail—Detenceless
condition of man.

Ir 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! 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- 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.’
The muscles are eminently variable: thus those of the foot
were found by Prof. Turner‘ not to be strictly alike in any two
out of fifty bodies; and in some the deviations were considerable.

1 ‘Investigations in Military and
Anthropolog. Statistics of American
Soldiers,’ by B. A. Gould, 1869, p.
258.

2 With respect to the ‘Cranial
forms of the American aborigines,”
see Dr, Aitken Meigs in ‘ Proc
Acad. Nac. Sci.’ Philude"phia, May,
1868. On the Austialians, ee

Huxley, in Lyell’s * Antiquity of
Man,’ 1863, p. 87. On the Sand-
wich Islanders, Prof. J. Wyman,
“Observations on Crania,’ Boston,
1868, p. 18.

* ‘Anatomy of the Arteries,’ by
R. Quain. Preface, vol. i. 1844,

‘ «Transact. Royal Soc. Edin
burgh,’ vol. xxiv. pp. 175, 189.

ouap, 11, Manner of Development. 27

He adds, that the power of performing the appropriate move-
ments must have been niodified in accordance with the several
deviations. Mr. J. Wood has recorded’ 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 muny
ways: thus Prof. Macalister describes® no less than twenty
distinct variations in the palmaris accessorius,

The famous old anatomist, Wolff,’ insists that the internal
viscera are more variable than the external parts: Nulla parti-
cula est gue 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, é&c., 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 uotorious that not a word need
here be said. So itis 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 men-
tions 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 manncr in which they
have been treated or educated.®

I have elsewhere® so fully discussed the subject of Inheritance,
that I need here add hardly anything. A greater number of

5 ¢ Prog, Royal Soc.” 1867, p. ® Brehm, ‘Thierleben,’ B. us.
544.3 also 1868, pp.483,524, There 58, 87. Rengger, ‘Saugethiere ven

is a previous paper, 1866, p. 229, | Paraguay,’ s, 57.
6 «Proc. R. lrish Academy,’ ve). ® ‘Variation of Animals and
x. 1868, p. 141. Plants under Dumestication,’ vol

7 ‘Act. Acad, St. Petersburg,’ i, chap. xii,
1778, part i, > 217

28 The Descent of Man. Part L

facts have been collected with respect tg the transmission of the
most trifling, as well as of the most important characters m
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, &c.,
are certainly transmitted. With man we see similar facts in
almost every family; and we now know, through the admirable
labours of Mr. Galton,° 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 deteri-
orated 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;
aud 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." 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”! 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 Jong been controlled, either by methodical
or unconscious selection. No race or body of men has been so

10 ‘Hereditary Genius: an In-
quiry into its Laws and Conse-
quences,’ 1869,

1 Mr. Bates remarks (‘ The Natu-
ralist 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
‘im the shape of the head; one

“ man had an oval visage with fine
“features, and another was quite
“Mongolian in breadth and pro
‘*minence of cheek, spread of nos
“ trils, and obliquity of eyes.”

12 Blumenbach, ‘ Treatises on An-
thropolog.’ Eng. translat., 1865, p.
205.

Cuap. II. Manner of Development. 29

completely subjugated by other men, as that certain individuals
should be preserved, and thus unconsciously selected, from some-
how 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 grena-
diers; and in this case man obeyed, as might have been ex-
pected, 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 selec-
tion 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.*

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 la a tae
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

13 Mitford’s ‘History of Greece,’
vol. i, p. 282. It appears also from

vigour of their children. The Gre-
cian poet, Theognis, who lived 550

& passage in Xenophon’s ‘ Memora-
bilia,’ B. ii. 4 (to which my atten-
tion has been called by the Rev.
J. N. Hoare), that it was a well
recognised principle with the Greeks,

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

chat men ought to seiect their wives selection. He thus writes:

with a view to the health and

“ 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 mouey’s sake,
Men marry: women are in marriage given 5
The chur] 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 ns a degraded, motley kind,
‘Wondex ao more, my friend! the cause is plain,
And te jament the consequence is vain.”

(The Works cf J. Hookham Frere, vol. ii. 1872, p. 334.?

Part 1

30 The Descent of Man.

Quatrefages, that I need here only refer to their works.4 Mon-
strosities, which graduate into slight variations, are likewise 90
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!® In my work on the variation of
domestic animals, I have attempted to arrange in a rude fashion
the laws of variation under vhe following heads :—The direct and
detinite 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 ;'*
but several are so important, that they must be treated at con-
siderable length.

The direct and definite action of changed conditions—This is a
most perplexing subject. It cannot be denied that changed cun-
ditions 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 1 have failed to obtain clear evidence in favour of this con-
clusion; 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 rend-
ered in some degree plastic.

In the United States, above 1,000,090 soldiers, who served in
the late war, were measured, and the States in which they were

M44 Godron, ‘De I’Espéce,’ 1859,

18 T have fully discussed these
tom, ii. livre 3. Quatretages, ‘ Unite

laws in my ‘ Variation of Animals

de I’kspéce Humaine,’ 1861. Also
L:ctures on Anthropology, given in
the ‘ Kevue des Cours Scientifiques,’
1866-1808.

'5 «Hist. Gén, et Part. des Ano-
malice de )’Organisation,’ in tnree
voluinies, tom. i, 1832,

and Plants under Domestication,’
vol. ii, chap. xxii. and xxiii, M. J.
P. Durand has lately (1868) pub-
lished a valuable essay ‘De I’In-
fluence des Milieux,’ &. He lays
much stress, 1n the case of plants, on
the nature of the sil.

Crap. JI. Manner of Development.

31

Lorn and reared were recorded.” From this astonishing numbor
of ubservations 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 greut 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 Villermé, 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," or again between the Fuegians on the eastern
and western shores of their country, where the means of subsis-
tence are very different, it is scarcely possible to avoid the con-
clusion 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 occupa-
tions 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.” ?

Whether external conditions produce any other direct effect
on man is not known. It might have been expected that dif-
ferences of climate would have had a marked influence, in as much
as the lungs and kidneys are brought into activity under a low

iy ‘Investigations in Military and 289. There is also a remarkable

Anthrop. Statistics,’ &c. 1869, by
B. A. Gould, p. 93, 107, 126, 131,
134, °

18 For the Polynesians, see Prich-
ard’s ‘Physical Hist. of Mankind,’
vol. v. 1847, p. 145, 283. Also
Godron, ‘De VEspéce,’ tom. ii. p.

difference in appearance between
the closely-allied Hindoos inhabiting
the Upper Ganges and Bengal; see
Elphinstone’s ‘ History of India,’ vol.
i. p. 324,

'8 ¢Memoirs, Anthropolog. Soc
vol. iii. 1867-69, pp. 561, 565, 567

32 The Descent of Man. Parr t.

d

temperature, and the liver and skin under a high one.” 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 man-
kind. 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 inervased 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.”
Different occupations, habitually followed, lead to changed
proportions in various parts of the body. Thus it was ascertained
by the United States Commission ” 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, ont 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 weigbts.
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 ” aitri
butes the thin legs and thick arms of the Payaguas Indians to

20 Dr. Brakenridge, ‘Theory of
Diathesis,’ ‘ Medical Times,’ June 19
and July 17, 1869.

21 | have given authorities for
these several statements in my
‘Variation of Animals under Do-
mestieation,’ vol. ii. pp. 297-300.

Dr. Jaeger, “Ueber das Tangen-
wachsthum der Knochen,” ‘Jena-
ischen Zeitschrift,’ B. v. Heft i

#2 <Tnvestigations, &c. By ». a
Gould, 1869, p. 288.

23 ¢Séugethiere von Paraguay
1830, ». 4.

nar IT. Manner of Devetopmenn. 33

suce-esive generations having passed nearly their whole lives in
eanoes, with their lower extremities motionless. Other writers
have come to a similar conclusion in analogous cases. According
to Cranz,* 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.“ From the correlation which exists, at least in
some cases,”* 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“ 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;% and it can hardly be doubted that this is due
to the inherited effects of pressure during a long series of
generations.

lt 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.” Short-
sight and long-sight certainly teud to be inherited® The
inferiority of Europeans, in comparison with savages, in eye-
sight and in the other senses, is no doubt the accumulated and
transmitted effect of lessened use during many generations; for
Rengger® states that he has repeatedly observed Europeans,

34 ‘History of Greenland,’ Eng.
translat. 1767, vol. i. p. 230.

23 ‘Tntermarriage.” By
Walker, 1838, p. 377.

28 The Variation of Animals
vader Domestication,’ vol. i. p. 173.

27 ¢Principles of Biology,’ vol. i.
p. 455.

28 Paget, ‘Lectures on Surgica!
Fathology,’ vol. ii. 1853, p. 209.

2 It is a singular and unex-
pected fact that sailors are inferior
to landsmen in their mean distance
at’ distinet vision. Dr. B. A. Gould

4

Alex.

(‘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 “ re-
“ stricted to the length of the vessel
“and the height of the masts.”

30 ¢The Variation of Animals
under Domestication,’ vol. i. p. 8.

31 ‘Saugethiere von Paraguay,’
s.8,10. Ihave had good opportupi-
ties for observing the extraordinary
power of eyesight in the Fuegians.
See also Lawreace (‘Tectures op

The Descent of Man.

Part i,

34

who had been brought up and spent their whole lives with the
wild Indians, who nevertheless did not equal them in the sharp-
ness 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 dimen-
sions 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.”

The Quechua Indians inhabit the lofty plateaux of Peru; and
Alcide d’Orbigny states* 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 observa-
tions 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* 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 tibis were as 244
4o 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

Physiology,’ &c., 1822, p. 404) on

bach, vol. i. 1851, p. 311; for the
this same subject. M. Giraud-Teulon

statement by Pallas, vol. iv. 1844,

kas recently collected (‘ Revue des
Cours Scientifiques,’ 1870, p. 625)
a large and valuable body of evidence
proving that the cause of short-
sight, “ Cest le travail assidu. de
pres.”

» Prichard, ‘Phys. Hist. of Man-
kind,’ on the authority of Blumen-

p- 407.

33 Quoted by Prichard, ‘Re
searches into the Phys. Hist. of Man-
kine,’ vol. v. p. 463.

34 Mr. Forbes’ valuable paper is
now published in the ‘Journal ef
the Ethnological Scs, of London,’
new series, vol. ij. 1870, p. 193.

Cuar. IL. Manner of Development 35

relation with the greatly increased length of the trunk. The
Aymiaras 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 Spaniarda
to the low eastern plains, and when now tempted down by higk
wages to the gold-washings, they suffer a frightful rate of mor-
tality. 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 thcse of the men on the high
plateau ; whilst their femora had become somewhat lengthened,
as had their tibie, although in a less degree. The actual
mneasurements 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.*

Although man may not have been much mo.ified during
the latter stages of his existence through the increased or de-
creased 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 Develonpment.—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
suftice for our purpose to refer to the arrested brain-development
of microcephalous idiots, as described in Vogt’s memoir.
Their skulls are smaller, and the convolutions of the brain
are less complex than in normal men. The frontal sinus, or the

35 Dr. Wilckens (‘Landwirth- regions, have their frames modified.
schatt. Wochenblatt,’ No. 10, 1869) 36 “Mémoire sur les Microcé-
has lately published an interesting phales,’ 1867, pp. 50, 125, 169, 171,
Nssay shewing how domestic ani- 184-198.
uals, which live in mountainous

36 The Descent of Man. Part ~

projection over the eye-brows, is largely developed, and the jawa
are prognathous to an “effrayant” degree’ so that these idiots
somewhat resemble the lower types of mankind. Their in-
telligence, 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
gamboling 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. Oune 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 becn published of their bodies being re-
markably hairy.”

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.* There are other cases which come

® Prof. Laycock sums up the pp. 46-51. Pinel has also given a

character of brute-like idiots by
calling them theroid; ‘Journal of
Menta. Science,’ July 1863. Dr.
Scott (‘Ths Deaf and Dumb,” 2nd
edit., 1870, p 10) has often ob-
served the imbecile smelling their
food. See, on tnis same subject,
and on the hairiness of idiots, Dr.
Maudsley, ‘ Body and Mind,’ 1879,

striking case of hairiness in au
idiot.

38 In my ‘ Variation of Animals
under Domestication ’ (vol. ii. p. 57),
I attributed the not very rare cases
of supernumerary mamme in women
to reversion. I was led to this as a
probable conclusion, by the additional
mammex being generally plicad

Onap. IL.

Manner of Development.

37

more strictly under our present head of roversion.

Certain

structures, regularly occurring in the lower members of the group

symmetrically on the breast; and
more especially from one case, in
.which a single efficient mamma
occurre] in the inguinal region of
a woman, the daughter of another
woman with supernumerary mam-
mx. But I now tind (see, for in-
stance, Prof. Preyer, ‘Der Kampf
um das Dasein,’ 1859, s. 45) that
mammne erratice occur in other
situations, as on the back, in the
armpit, and on the thigh; the
mamme in this latter instance
having given so much milk that the
child was thus nourished. The pro-
bability that the additional mammas
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
mamme on the breast. Five cases
have been recorded of the presence
of more than a pair of mamme (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
mamme, 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 mammie
would ever have been developed in
both sexes of mankind, had not his
early progenitors been provided
with more than a single pair.
To the above work (vol. ii. p. 12),

Talso 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 Ich.
thyopterygia possess more than five
digits, and therefore, as I supposed,
had retained a primordial condition;
bat Prof. Gegenbaur (‘ Jenaischen
Zeitschrift,’ B. v. Heft 3, s. 341),
disputes Owen’s conclusion. On the
other hand, according to the opin-
ion lately advanced hy Dr. Giinther,
on the paddle of Ceratodus, which is
provided with articulated boay 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 in-
herited, but, as I then believed, had
the power of regrowth after ampu-
tation, like the normal digits of the
lower vertebrata. But TI have ex-
plained in the Second Edition of my
Variation under Domestication why
T now plaice little reliance on the
recorded cases of such regrowth,
Nevertheless it deserves notice, in
as much as arrested development
and reversion are intimately related
processes; that various structures
in an embryonic or arrested con.
dition, such as a cleft palate, bifié
uterus, &., are frequently accom-
panied by polpdactylism. This hag
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

Pant [

38 The Descent of Man.

to which man bloags, occasionally make their appearance iv
him, though not found in the normal human embryo; or, if
normally present in the hnman embryo, they become abnormally
developed, although in a manner which is normal in the lower
members of the grovp. These remarks will be rendcred clearer
by the following illustrations.

In various mammals the uterus graduates from a double
crgan, with two distinct orifices and two passages, as in tlie
mursupials, 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
“ extremitics that the body of the uterus is formed in man;
“while in those animals in which no middle portion of body
“ exists, the cornua remain uu-united. 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 nterus.” The angles of the uterus are still pro-
duced 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 paztially
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.” 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 twa

there is any relation between the
development of supernumerary di-
gits and reversion to some lowly
organised progenitor of man.

% See Dr. A. Farre’s well-known
article in the ‘Cyclopadia of

Anatomy ard Physiology,’ vol. +.,
1859, p. 642. Qwen, ‘ Anatomy
of Vertebrates,’ vol. iii, 1868, p.
687. Professor Turner in ‘ Edin
burgh Medical Journal,’ February,
1865.

Onap. II, Manner of Development.

39

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 donble
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 develop-
ment, 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,” 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 develop-
ment, 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
oecame 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 Cauestrini has observed, in
those exhumed from the Drift, and belonging to the brachyce-
phalic type. Here again he comes to the same conclusion as in
the analogous case of the malar hones. 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

4 ¢ Annuario della Soc. dei Natu-
ralisti_ in 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 cannet 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
sraces of the division may be de-

tected in about two per cent. of
adult sku: ; he also remarks that
it more tieynently occurs in pro-
gnathous 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 throws
doubts on my stutements.

Part L

40 The Descent of Man.

zreater 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 nota little doubtful, for we have te
descend extremely low in the mammalian series, before we find
such structures normally present.*!

In man, the canine teeth are perfectly efficient instruments for
mastication. But their true canine character, as Owen® re~
marks, “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
Hiickel * 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 interspace of this kind in a Kaffir
skull, figured by Wagner, is surprisingly wide.** Considering
how few are the ancient skulls which have been exainined,
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.

4! A whole series of cases is given
by Isid. Geoffroy St.-Hilaire, ‘ Hist.
des Anomalies,’ tom. iii. p. 437.
A reviewer (‘ Journal of Anat. and
Physiology,’ 1871, p. 366) blames
me much for not having discussed
the numerous cases, which have
been recorded, of various parts ar-
rested in their development. He
ssys 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 initself.” This
does not seem to me necessarily to
hold good. Why should aot varia-
tions occur during ap early per:od
of development, having no relation
ta reversions vet such variations
wight be preserved aud secumulsted,

if in any way serviceable, for in-
stance, in shortening and simplifying
the course of development? And
again, why should not injurious ab-
normalities, such as atrophied or hy
pertrophied parts, which have na
relation to a former state of exist-
ence, occur at an early period, aa
well as during maturity ?

#2 ¢ Anatomy of Vertebrates,” vol,
iii. 1868, p. 323.

43 “Generelle Morphologie,’ 1866,
B. ii. s. elv.

44 Carl Vogt’s ‘Lectures on Man,
Eng. translat. 1864, p. 151.

4% C. Carter Blake, on a jaw
from La Naulette, ‘Anthropolog
Review,’ 1867, 295. Schaaff
bausen, ihid. 1868, p. 426,

Onap. II, Manner of Development.

4l

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 isa 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 pro-
vided 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),** 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 * 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. Thi-
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,** has minutely
described a vast number of muscular variations in man, which
resemble normal structures in the lower animals. The muscles

48 ¢The Anatomy of Expression,’

pp. 241, 242; vol. xv. 1867, p. 5443
1844, pp. 110, 131.

vol. xvi. 1868, p. 524. I may here

47 Quoted by Pref. Canestrini in
the ‘Annuario,’ &., 1867, p. 90.

43 These papers deserve careful
study by any one who desires to
learn how frequently our muscles
vary, and in varying come to re-
semble those of the Quadrumaaa.
The folicwing references relate to
the few pvints touched on in my
text: ‘Proc. Royal Soe vol. xiv.
1865, pp. 379-384; vol. xv. 1866,

add that Dr. Murie and Mr. St.
George Mivart have shewn in their
Memoir on the Lemuroidea (* Tran:
-act, Zoolog. Soe.’ vol. vii. 1869,
p. 96), how extraordinarily variable
some of the muscles are in these
animals, the Jowest members of the
Primates. Gradations, also, in the
muscles leading to structures fourd
in animals still lower in the scale
are numerous in the Lemuroidea.

The Descent of Man.

Part Ll.

42

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 weil-formed skull, no less than seven muscular varia-
tions 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 cluvicule,”
such as is found in all kinds of apes, and which is said to occur
ja about one out of sixty human subjects.” 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-hasilur muscle is found
in all mammals below man, and seems to be correlated with a
quadrupedal gait, and it occurs im about one out of sixty
human subjects. In the lower extremities Mr. Bradley” found
an abductor ossis metuturst quintt 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.” Such resem-
blances 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.”

49 See also Prof. Macalister in
‘Proc. R. Irish Academy,’ vol. x.
1868, p. 124,

50 Mr, Champneys in ‘ Journal of
Anat. and Phys.’ Nov., 1871, p. 178.

51 ‘Journal of Anat. and Phys.’
May, 1872, p. 421.

52 Prof. Macalister (ibid. p. 121)
has tabulated his observations, and
finds that muscular abnormalities
are most frequent in the fore-arms,
recondly, in the face, thirdly, in the
foot, &c.

53 The Rev. Dr. Haughton, after
giving (‘Proc. R. Irish Academy,’
Jane 27, 1864, p. 715) a remark-

able case of variation in the human
jlexor pollicis longus, adds, ‘This
“yemarkable 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 under-
“take to say.” It is satisfactory
to hear so capable an «anatomist,
and so embittered an opponent of
evolutionism, admitting even the

Unar. II, Manner of Development. 43

That this unknown factor is reversion to a former state of
existence may be admitted as in the highest degree probable.
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 thou-
sand generations, in the same manncr 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 rudi-
mentary in man, as the os coccyx in both sexes, and the wamme
in the male scx, are always present; whilst others, such as the
supracondyloid foramen, only occasionally appear, and therc!ore
might have been introduced under the head of reversion. These
several reversionary structures, as well as the strictly rudi-
mentary ones, reveal the descent of man from some lower form
in an unmistakable manner.

Correlated Vuriation—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

closely the variations resemble the
normal muscles of the lower ani-
mals. He sums up by remarking,

possibility of e:ther of his first pro-
positions. Prof. Macalister has also
described (‘ Proc. R. Irish Acad.’

vol. x. 1864, p. 188) variations in
the flexor pollicis longus, remarkable
trom their relations to the same
muscle in the Quadrumana.

44 Since the first cdition of this
book appeared, Mr. Wood has pub-
lished another memoir in the ‘ Phil.
Transactions,’ 1870, p. 83, on the
varieties of the muscles of the human
yeck, shoulder, and chest. He here
shews how extremely variable these
muscles «re, and how often and how

“ 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 ia
“ a sufficiently marked manner what
“ may be considered as proofs and
“examples of the Darwinian prin-
“ ciple of reversion, or law of in-
“ heritance, in this department ct
“ anatomical science.”

4 The Deszent of Man. Part 1,

part. Various monstrosities, as I. Geoffroy repeatedly insists, are
thus intimately connected. Homologous structures are par-
ticularly 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, thet 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 cor-
related.*5 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 condi-
tions to which it has been subjected.**

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 calcula-
tion by Euler, this might occur in a little over twelve years.” 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
syuare 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

“8 The authorities for these seve- my ‘ Variation of Animals and Plante
ral statements are given in my under Domestication.’
‘Variation of Animals under Do- 57 See the ever memorable ‘ Essay
mesticaticn,’ vol. ii. pp. 320-335. on the Principle of Population,’ by
56 This whole sabject has been the Rev. T. Malthus, vol. i. 1826, p
diseusse. wn chaz. xxii. vol. ii, of 6, 517,

Onap. I, Manner of Development. 45

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 itis 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,* 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 ae
objection to this conclusion that animals suddenly supplied wit
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.

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 San-
tali, or hill-tribes of India, have recently afforded a good illustra-
tion of this fact; for, as shewn by Mr. Hunter,” 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

38 ‘Variation of Animals and Foreign Medico-Chirurg. Review,’
Plants under Domestication,’ vol. ii. July, 1863, p. 170.
gp. 111-113, 163. 80 «The Annals of Rural Bengal.
59 Mr. Sedgwick, ‘British and by W. W. Hunter, 1868, p. 259.

46 The Descent of Man. Part i

earliest possible age. The young menare often required to shew
that they can support a wife; and they generally have first to
earn-the price with which to purchase ber 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
cmaciated 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 period-
ical, 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. i

| Malthus has discussed these several checks, but he does not

i 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® has shewn, on a still more extensive
scale. These practices appear to have originated in savages re-
cognising 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 mneans 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 ” as to lead them re-

* ¢Primitive Marriage,’ 1865, ments as follows on this passage :—
* A writer in the ‘Spectator’ ‘ Mr. Darwin finds himself compelled
(March 12th, 1871, p. 320) com “to reintroduce a new doctrine of the

Cnat II. Manner of Development.

47

gularly 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 pro-
genitors 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,® to the most diversified con-
ditions. 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,

“ fall of man. Heshews that the “by the many foul customs, es-

“instincts of the higher animals
‘ave far nobler than the habits of
** savage races of men, and he finds
“himself, therefore, compelled to
“ ye-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

* pecially as to marriage, of savage
“tribes. What does the Jewish
“ tradition of the moral degenera-
“ tion of man through his snatching
“at a knowledge forbidden him
“by his highest instinct assert
“ beyond this ?”

83 See some good remarks to this
effect by W. Stanley Jevons, “A
“ Deduction from Darwin’s Thecry,”
‘Nature,’ 1869, p. 231.

48 The Descent of Man. Part J,

and changed their habits many times, before they rcached their
present homes.“ 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 tc 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. 1 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,®
to incessant variability. If then the progenitors of man inhabit-
ing 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 that 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. Thesupreme 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 :* “ 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, &c., with which
he defends himself, kills or catches prey, and otherwise obtains
food. He has mado rafts or canoes for fishing or crossing over

to neighbouring fertile islands.

6 Latham, ‘Man and his Migra-
fons,’ 1851, p. 135.

6S Messrs, Murie and Mivart in
thei: ‘Anatomy of the Lemurordea’
(‘ Transact. Zoolog. Soc. vol. vii.
1869, pp. 96-98) say, ‘some muscles
“ are so itregulai in their distribu-
“tion that they ecmact be well

He has discovered the art of

“classed in any of the above
“ groups.” These muscles differ
even on the opposite sides of the
same individual.

8° Limits of Natural Selection,
‘North American Review,’ Oct
1870, p. 295.

Cuap. IT. Manner of Development. 49
making fire, by which hard and stringy roots can be rendered
digestible, and poisonous roots or herbs innocuous. This dis-
covery 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 main-
tains, 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 socia] habits of man are
of paramount importance to him, we must not underrate the
importance of his bodily structure, to which subject the remain-
der of this chapter will be devoted; the development of the in-
tellectual 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 ajm 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. Schooleraft,** remarks,
the shaping fragments of stone into knives, lances, or arruw-heads,

&7 ‘Quarterly Review,’ April
1869, p. 392. This subject is more

here resist quoting a most just
remark by Sir J. Lubbock (‘ Pre-

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 republished. The ‘ Essay
on Man’ has been ably criticised by
Prof. Claparéde, one of the most
distinguished zoologists in Europe,
m an article published in the
Bibliothaque 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,’ origiaally pub-
lished in the ‘ Anthropolegical Re-
view, May 1864, p.clv ‘i, [ cannot

historic 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) unre-
« servedly to Mr. Darwin, although,
“as is well known, he struck out
“ the idea independently, and pub-
“lished it, though not with the
“same elaboration, at the same
“ time.”

88 Quoted by Mr. Lawson Tait in
his ‘Law of Natural Selection,’—
‘Dublin Quarterly Journal of Medi-
cal Science,’ Feb. 1869. Dr. Keller
is likewise quoted to the same
effect.

50 The Descent of Man. Part‘

shews “ extraordinary ability and long practice.” This is to &
great extent proved by the fact that primeval men practised &
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. Archeologists aru 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 arn.
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 diver-
sified 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.** 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 the 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 mysclf seen, are quite unable tw
throw a stone with precision.

* Owea, Anatomy of Vertebrates,” vcl. ii, p, 71

Manner of Development. §1

cuaF, II,

It.seems to me far from true that because “ objucts are grasped
“elumsily” by monkeys, “a much less specialised organ of
“ prehension” would have served them™ 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.”

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;” and
they have acquired almost the gait of a dog. Man alone kas
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 insists that “the hand supplies all instruments,
“and by its correspondence with the intellect gives him univer-
“ gal 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 }ocomotion 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

April but whesher a better climber than

the species of the allied genera, I de
not know. It deserves notice that

7 ¢ Quarterly Review,’
1869, p. 392.
™ 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 A. agilis,
‘ar, and leuciscus. Colobus is strictly
arboreal and extraordinarily active
(Brehm, ‘Thierleben,’ B. i. 3. 50),

the feet of the sloths, the most
arboreal animals in the world, are
wonderfully hook-like.

7 Brehm, ‘Thierleben,’ B. i.
80

73 «<The Hand,” &c. ‘Bridge
water Treatise,’ 1833, p. 38.

52 The Descent of Man. Part |,

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 modi-
fied, 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 pre-
hension, 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.”

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 sec
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 other-
wise 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 miscrably 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

™ Hackel has an excellent dis-
cussion on the steps by which man
became a biped: ‘ Nattirliche Schop-
fungsgeschichte,’ 1868, s. 507. Dr.
Buchner (+ Conférences sur la Thsorie
Darwinienne,’ 1869, p. 135) has
given guod cases of the ase of the

foot as « 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. iti, p. 71) on
this latter subject.

Onae. IL, Manner of Developmen. 53

biped; but, as an unprejudiced judge” insists, the anthropomor-
vhous 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
dhanges 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”™ 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, &c., 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 com-
plete 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
feeth and hoofs.

13 Prof, Broca, La Censtitution the Skull,’ translated in ‘ Anthro-
des Vertabres cawlales; ‘La Revue pological Review,’ Oct. 1868, p.
d’Anthropologie;’ 1872, p. 26, 428. Owen (‘Anatomy of Verte-
{separate copy) brates,’ vol. ii. 1866, p. 551) on the

1% ¢Op the P imitive Form of mastoid processes in the higher apea

54 The Descent of Man. Part 1

In the adult male anthropomorphous apes, as Riitimeyer,”
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 became 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 iptelligent orders, such as beetles.”
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
eubic 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 ig
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 rélation 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,” by many careful measurements, that the mean internal
capacity of the skull in Europeans is 92:3 cubic inches; in
Anericans 87:5; in Asiaties 87-1; and in Australians only 81:9
citbic inches. Professor Broca® found that the nineteenth century

™ «Die Grenzen der Thierwelt,
exne Betrachtung zu Darwin’s Lehre,’
1868, s. 51,

7° Dujardin, ‘ Annales des Se.
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,

79 © Philosophical Transactions,
1869, p. 513.

S® «Les Sdlections,” M. P, Broca,

Cuar. II. Manner of Development. 55

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. With
respect to. the lower animals, M. E. Lartet,” 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® 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 yradually increasing weight of the brain and skull in
man must have influenced the development of the supporting
spinal coluyan, 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 show 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

4

‘Revue d’Anthropologies,’ 1873; the other hand, with savages, the ave-

see also, as quoted in C. Vogt’s
‘Lectures on Man,’ Eng. translat.
1864, pp. 88, 90. Prichard, ‘ Phys.
Hist. of Mankind,’ vol. i. 1838, p.
305.

5! 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 preserva-
tion of a considerable number of
individuals, weak in mind and body,
who would have been promptly
eliminated in the savage state. On

rage includes only the more capable
individuals, who have been able to
survive under extremely hard con-
ditions of life. Broca thus explains
the otherwise inexplicable fact, that
the mean capacity of the skull of
the ancient Troglodytes of Lozére is
greater than that ot modern French-
men,

82 «Comptes-rendus des Sciences,’
&c. June 1, 1868.

83 ¢The Variation of Animals and
Plants under Domesticatina,’ vol. a
pp. 124-129,

56 The Descent of Man. Paut L

apparently by the pressure of the brain in a new direction.™
Ihave 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 wouid 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 ove 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.* One of the must marked distinctions in different races
of men is that the skul) 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 ;”8* and
tall men may be compared with the larger and longer-bodied
rabbits, all of which have elongated skulls, or are dolicho-
cephalic.

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

84 Schaaffhausen gives from Blu-
menbach and Busch, the cases of the
spasms and cicatrix, in ‘ Anthro-

olog. Review,’ Oct. 1868, p. 420.

r. Jarrold (‘ Anthropologia,’ 1808,
pp. 115, 116) adduces from Camper
and from his own observations, cases
of the modification of the skull from
tae head being fixed in an unnatural
position. He believes that in cer-

ain trades, such as that of a shoe-

maker, where the head is habitually
held forward, the forehead becomes
more rounded and prominent.

85 «Variation of Animals, &c.,
vol. i. p. 117, on the elongation of
the skull; p. 119, on the effect of
the lopping of one ear.

8° Quoted by Schaaffhausen, in
‘Anthropolog. Review,’ Oct. 1868,
p. 419.

Cuap. IT, Manner of Development.

57
through the water; nor would it be injurious to them from the
ioss 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 scals and otters, Elephants and rhino-
ceroses 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
gpecies 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 ™
than those on the lowlands. May we then infer that man
became divested of hair from having aboriginally inhabited some
tropical Jand? 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
surtace,** is opposed to the supposition that man became naked
through the action of the sun. Mr. Belt believes ® 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,

87 Owen, ‘Anatomy of Verte-
brates,’ vol. iii. p. 619.

88 |sidore Geoffroy St.-Hilaire re-
maiks (‘ Hist. Nat. Générale,’ tom.
ii, 1859, pp. 215-217) on the head of
man being covered with long hair;
aiso on the upper surfaces of mon-
keys and of other mammals being
more thickly clothed than the lower
surfaces. This has likewise been
observed by various authors. Prof.
b. Gervais (Hist. Nat. des Mam-
wiferes,’ tom. i. 1854, p. 23), how-

ever, states that in the Gorilla the
hair is thinner on the back, where
it is partly rubbed off, than on the
lower surface.

8 The ‘ Naturalist in Nicaragua,’
1874, p. 209. As some contirma-
tion of Mr. Belt’s view, 1 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 Aus-
“tralians, when the vermin gel
“ troublesome, to singe themselves ’

58 The Descent of Man. Parr I,

became divested] of hair for ornamental purposes, as we shall sea
under Sexual Selection; anu, acccrding 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 degt.e in closely-related fortas.
According to a popular impression, the absence of a tuil 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
vertebre; in others it consists of a scarcely visible stump,
containing only three or fonr vertebre. In some kinds of
baboons there are twenty-five, whilst in the mandrill there are
ten very small stunted caudal vertebre, or, according to Cuvier,
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 dis-
appearance of the tail. Professor Broca has recently shewn™
that the tail in all quadrupeds consists of two portions, generally
separated abruptly from each other; the basal portion consists
of vertebra, more or less perfectly chunnelled and furnished with
apophyses like ordinary vertebre ; whereas those of the terminal
portion are not channelled, are almost smooth, and scarcely
resemble true vertebrze. 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 vertebre, 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 vertebra. These are of functional
importance by supporting certain internal parts and in other
ways; and tkeir modification is directly connected with the erect

°° Mh). St. George Mivart, ‘Proc. Geoffroy, ‘Hist. Nat. Gén. tom. ii
Zoolog. Soc.’ 1865, yp. 56%, 583, p. 244,
Dr. J. E. Gray, ‘Cat. Brit. Mus.: ®! ‘Revue d’ Anthropologie,’ 1872 ;
Skeletons.’ Owen, ‘Anatomy of ‘La Const.trt’on des Vertébres can:
Vertebrates,’ vel. ii. p 517. isidore — dales,’

Cuap, II, Manner of Development. 59

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 modifica-
tion, therefore, of the basal caudal vertebra 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 coccys:?
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™ states
that the extremely short tail of Macacus brunneus is formed of
eleven vertebre, including the imbedded basal ones. The
extremity is tendinous and contains no vertebre; this is suc-
ceeded 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 vertebra. 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 observa-
tions: “ 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 circum-
stances it is not surprising that the surface of the tail should
have been roughened and rendered callous; and Dr. Murie,® who
earefully 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

% ¢Proc, Zoolog. Soc.,’ 1872, p. °3 Proc, Zoolog. Soc. 1872, p
370. 786.

Part .

50 The Descent of Man.

have evidence that mutilations occasionally produce an inherited
effect, 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 MV. 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 wo
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. Itis 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; *° 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

% T allude to Dr. Brown-Séquard’s
ebservatiuns on the transmitted
affect of an operation causing epi-
(psy in guinea-pigs, and likewise
more recently on the analogous
effects of cutting the sympathetic
terve in the neck, I shai hereafter
have occasion to refer to Mr. Salvin’s
interest'ng case of the appacently

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,

8° +The Variation of Animals and
Plants under Domestication,’ vol. ii
pp. 280, 282, -

Onap. IL Manner of Development. 61

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, mora
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 hot 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
nat, BSWEvaE, 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 selec-
tion, 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

52 The Descent of Man. Parr 1

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 frobably 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 beneficia], cannot be kept uniform through natural
selection, though the injurious will be thus eliminated. Uni-
formity 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 spon-
taneous 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 tho
present day is ‘liable, like every other animal, to multiform
individual differences or slight variations, so no doubt were the
ewrly 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 Icad 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 uniferm~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 victo-
rious over other less favoured ones; even although each separate

Cnar. IT. Manner of Development. 63

member gains no advantage over the others of the same com-
munity. Associated insects have thus acquired many remark-
able 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® 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
slaws 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
‘njury to the inhabitants of a warm country. For we know that the
uiclothed Fuegians can exist under a wretched climate. When
we compare the defenceless state of man with that of apes, we
inust 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

96 « Primeval Man,’ 1869, v. 66,

54 The Descent of Man. Parr 1

and weaker, than his ancestors. We should, however, bear in
inind 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
coight have been an immense advantage to man to have sprung
irom some comparatively weak creature.

The small strength and speed of man, bis want of natural
weapons, éc., are more than counterbalanced, firstly, by his
intellectual powers, through which he has formed for himself
weapons, tools, &c., 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, &c. 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.

Muar. LIT. Mental Powers. 65

CIIAPTER Ii.

CoMPARISON OF THE Mental Powers oF MAN AND THE
Lowrr 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! 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 adog 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 jived some years in England, and could talk a little
Fnglish, 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

' See the evidence on those points, as given by Lubbock, ‘Prehistoric
imes,’ p. 354, &e.
6

86 The Descent of Man. Pagz |

Byron, who dashed his child on the rocks for dropping a basket
of sea-urchings, 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 thai
they mignt pass and be developed into each other.

My object in this chapter is to shew that there is no funda-
mental difference between man and the higher mammals in theiz
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 con-
venient 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
sume 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
owest organisms, is as hopeless an enquiry as how life itself

rst originated. These are problems for the distant future, if
hey 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 plat-
forms 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

Cuar. III. Mental Powers. 67

frarned 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
ower 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,? 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
‘east 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.’

Although the first dawnings of intelligence, according to Mr.
Herbert Spencer,* have been developed through the multiplica-
tion 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 ease 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 con-
verted 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 ave 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 varia-
tions 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 dif
‘erences in other parts of the body; and these variations, owing

2 ¢TInstinct chez les Insectes.’ 3 ¢The American Beaver and his
Revue des Deux Mondes,’ Feb. 1870, Works,’ 1868.
p. 690. 4 <The Principles of Psychology,

2nd edit. 1870, pp. 418-443.

68 The Descent of Man. Part 1.

to onr ignorance, are often said to arise spontaneously. We can,
{ think, come to no other conclusion with respect to the origin of
the more complex instincts, when we reflect on the marvelious
instincts of sterile worker-ants and bees, which leave no off-
spring 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 conse-
quence, 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 en-
couraged.

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,’ 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

* *Contiibutions to the Theory of Natural Seiection,’ 1870, p. 212.

(map. LT. Mental Powers.

69

& spider its wonderful web, quite as well,® 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, &c., when playing together, like our
own children. Even insects play together, as has been described
by that excellent observer, P. Huber,’ 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 ourdogs. 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 show it.
Many, and probably true, anecdotes have been published on the
long-delayed and artful revenge of various animals. The
accurate Rengger, and Brehm ® 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 after-
wards the baboon rejoiced and triumphed whenever he saw his
victim.

6 For the evidence on this

§ All the following statements,

head, see Mr. J. Traherne Mog-
gridge’s most interesting work,
‘Harvesting Ants and Trap-door
Spiders,’ 1873, p. 126, 128.

7 ‘Recherches sur les Meurs des
Fourmis,’ 1810, p. 173.

given on the authority of these two
naturalists, ale taken from Rengger’s
‘Naturgesch. der Saiugethiere von
Paraguay,’ 1830, s. 41-57, and from
Brebim’s ‘ Thierleben,’ B. i. s. 10-87

Parr )

70 The Descent of Man.

The Love of a dog for his master is notorious; as an old
writer quaintly says,? “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 hava
felt remorse to the last hour of his life.

As Whewell” 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 ?” Wesee mater-
nal atfection 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." In the Zoological Gardens, I heard from the keeper
that an old baboon ((. chaemu) 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, asI saw,
was greatly discontented at being thus rejected, and it would,
like a naughty child, annoy and attack the young drill and mandrill

» Quoted by Dr. Lauder Lindsay,
o his ‘Physiology of Min’ in the
Lower Animals ;’ ‘ Journal of Mental
Science,’ April 1871, p. 38.

10 ¢ Bridgewater Treatise,’ p. £63.

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 owa
teeth the sharp little claws of a
kitten nearly five weeks old.

Usap. JIL. Mental Powers, 71

whenever it could do so with safety; this conduct exciting great
indignation in the old baboon. Monkeys will also, according tc
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 appro-
bation 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 teels 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
kecper 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 show 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 manceuvre,
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
hie monkeys exhibited, for snakes; but their curiosity was
gu yreat that they could not desist from occasionally satiating

72 Lhe Descent of Man. Part |

théir horror in a 1aost 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
heheld. Three species of Cercopithecus were the most alarmed ;
they dashed about their cages, and uttered sharp signal cries ot
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,” 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, peened 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.

The principle of Imitution 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 commence-
ment 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 per-
formed near them.* Desor® has remarked that no animal

2 [ have given a short account of Mammalia,’ 1841, p. 405,

of their behaviour on this occasion ™ Dr, Bateman ‘On Aphasia,
in my ‘Expression of the Emotions,’ 1870, p. 110.
p. 43. 3 Quoted by Vogt, ‘Mémoire su

OW. C. L, Martin, Nat Hist. les Microréphales,’ 1867, p. 168.

Onae. IL Mental Powers. 73

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,”
but whether this can be called voluntary imitation is another
question. Birds imitate the songs of their parents, and some-
times of other birds; and parrots are notorious imitators of any
sound which they often hear. Dureau de la Malle gives an
account ” 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 ac-
counts; 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 roll-
ing it about with his fore paws, and springing on it. A corre-
spondent assures me thata 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,

16 ‘The Variation of Animals and 17 ¢Annales des Sc. Nat.’ (tet
Plants under Domestication,’ vol. i, Series), tom. xxii. p. 397.

p. 27,

74 The Descent of Man Past |.

if he might kecp three or four of them for a few days, in order
to select one. When asked how he zould possibly learn so soon,
whether a particular monkey would turn out a good actor, he
answered that it all depended en 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, recogn sed
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 walk-
ing, and obeyed me, exactly as if I had parted with him only
half an bour before. A train of old associations, dormant during
five years, had thus been instantaneously awakened in his mind.
Even ants, as P. Huber ™ 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,” “ 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 in-
“voluntary 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” have vivid dreams, and this is shewn by their movements
and the sounds uttered, we must admit that they possess some

8 <Tes Mceurs des Fourmis,’ 2% Dr. Jerdon, ‘Birds of India,
1810, p. 150, vol. i. 1862, p. xxi. Houzeau says
- 1 Quoted in Dr. Maudsiey’s‘Phy- that his parokeets and cunary-birda
Hology and Patholcgy of Mind,’ .868, dreamt: ‘ Facultés Mentales,’ tom.
pr. 19 220. ii, p. 136.

Cnar. Ih. Mental Powers. 75

power of imagination. There must be something special, which
sauses dogs to howl in the night, and espccially during moonlight,
in that remarkable and melancholy manner called baying.
All dogs do not do so; and, according to Houzeau,”! they donot
then look at the moon, butat 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 Peason 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.* In future chapters
we shall sce that some animals extremely low in the scale appar-
ently display a certain amount of reason. No doubt it is often
difficult to distinguish between the power of reason anil that of
instinct. For iustance, Dr. Hayes, in his work on ‘The Open
Polar Sea,’ repeatedly remarks that his dogs, instead of continu-
ing to draw the sledges in a compact body, diverged and separ-
ated 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 ot
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. Mébius,”’ 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

21 ¢Facultés Mentales des Ani- I cannot help thinking, however,

maux,’ 1872, tom. ii, p. 181. that he goes too far in underrating
22 Mr. L. H. Morgan’s work on _ the power of Instinct.
The American Beaver,’ 1868, offers 23 ‘Die Bewegungen der Thiere,

a good illustration of this remark. &c., 187.5, p. 11.

76 The Descent of Man. Parr I

catch the other fishes, that he was sometimes completely
stunned. The pike went on thus for three months, but at las?
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 intro-
duced; 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™ 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 asif they knew that
adipin 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 ina
state of nature. Now, what is the difference between such

24 «Wacultés Mentales des Animaux,’ 1872, tom. ii. p. 265,

Onap. IIT. Mental Powers.

77

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 asso-
ciated in their minds. A cultivated man would perhaps make
soine 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 dis-
appointed; 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. 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, thpt he would take notice of much slighter circum-
stances 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 ever knew. But the higher
animals differ in exactly the same way in this power of associa-
tion 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 Jow 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; after-
wards 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

See his ‘Mr. Darwin’s

*5 Prof. Huxley has analysed with
admirable clearness the mental steps
oy which a man, as well as a dog,
arrives at a conclusion in a case
analogous to that given in my text.

article,
Critics,’ in the ‘Contemporary Re-
view,’ Nov. 1871, p. 462, and in hig
‘Critiques and Essays,’ 1873, p. 279.

78 The Descent of Man. Pant L

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.* :

The following cases relate to dogs. Mr. Colquhoun” 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
“ preatly 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 bave 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.

Il will conclude by quoting a remark by the illustrious
Humboldt.”® “The muleteers in 8. 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 expres-
“sion, 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,” all such facts as those above given.

2 Mr, Belt, in his most interest- p. 45. Col. Hutchinson on ‘Dog
ing work, ‘The Naturalist in Ni- Breaking,’ 1850, p. 46.
earagua, 1874 (p. 119), likewise 78 «Personal Narrative,’ Eng.
de:oribes various actions of a tamed translat., vol. iii. p. 106.

Cebus, which, I think, clearly shew 29 T am glad to find that so acute
that this animal possessed some a reasoner as Mr. Leslie Stephen
reasoning power. (‘Darwinism and Divinity, Essays

*7 «The Moor and the Loch,’ on Free-thinkiug,’ 1873, p. 80), im

Cuap. LIT. Mental Powers.

79

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, aud |
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
ditterent 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.’ 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 im-
possibility, 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,
&ec.; 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* that man alone is
capable of progressive improvement. That lie 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

It has, I think, now been shewn that man and the ci in|

“tures. It is difficult to under-

speaking of the supposed impassable
f o “stand how anybody who has eve

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 assump-
“tion that because you can give
“two things different names, they
“ must theretore have different na-

“kept a dog, or seen an elephant,
“can have any doubts as to an
“ animal’s power of performing the
“ essential processes of reasoning.”

30 See ‘Madness in Animals,’ by
Dr. W. Lauder Lindsay, in ‘ Journal
of Mental Science,’ July 1871.

31 Quoted by Sir C. Lyell, ‘ Ante
quity of Man,’ p. 497.

80 The Descent of Man.

Part I,

young animals can be caught much more easily than ola ones;
and they can be much more easily approached by an enemy.
Even with respect to old animals, itis 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.®?

If we look to successive genrrations, 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 ;* 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,** 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,*
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
Yormosa, as well as on the mainland of China. Mr. Swinhoe,**
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

32 For additional evidence, with
details, see M. Houzeau, ‘Les
Facultés Mentales,’ tom. ii. 1872,
p. 147.

38 See, with respect to birds on
ocetnic islands, my ‘ Journal of
Researches during the voyage of the
“ Beagle,” ’ 1845, p. 398. ‘ Origin
of Species,’ Sth edit. p. 260.

34 «Lettres Phil. sur |’Intelligence

des Animaux,’ nouvelle edit. 1802,
. 86.

35 See the evidence on this head
in chap. i. vo]. i. ‘On the Variation
of Animals and Plants under Do-
mestication.’

36 «Proc. Zoolog. Soc.” 1864, p
188.

Ouap. TIT, Mental Pewers. 81

exercise of all its faculties in avoiding extirpation by man, aa
weil 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 ttellect or other mental faculties, is to beg the
question of the evolution of species. We have seen that, ac-
cording 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 1n a state of nature cracks a native fruit, some-
what like a walnut, with a stone’ Rengger® 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 after-
wards 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 ot
nature.” J have secn 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‘?
states, on the authority of the well-known traveller Schimper,
that in Abyssinia when the baboons belonging to one specics
(¢. 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 pays wae

37 Savage and Wyman in ‘Boston 1830, s. 51-56.

Journal of Nat. Hist.’ vol. iv, 1845 - 39 The ‘Indian Field,’ March 4
44, p. 383, 1871. :
20 ‘Saugethiere von Paraguay,’ 40 « Thierleben,’ B. i. s. 79, 82.

7

82 The Descent of Man. Past 1.

actually closed for a time against the caravan. It deserves
notice that these baboons thus acted in concert. Mr. Wallace
on three occasions saw female orangs, accompanied by their
young, “ brezking 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 Ict 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® 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 avery important dis-
tinction ; but there appears tome much truth in Sir J. Lubbock’s
suggestion, 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 tem-
porary platforms; but as many instincts are largely controlled
by reason, the simpler ones, such as this of buildivg 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

‘1 ¢The Malay Archipeiage.’ vol. i+5, 147,
be 4084, pp. 87. ‘8 + Prehistoric Timos,’ 1955, p

42 ¢ Primeval Man,’ 1869, pp. 473, &c

Onar, III. Mental Powers. 83

over its head. In these several habits, we probably sev 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, Ment.
Individuality.—It would be very difficult for any one with eveu
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. 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 Biichner* 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,

‘* Mr. Hookham, in a letter to “5 “Conferences sur la Théorie

Prof. Max Miiller, in the ‘Birming- Darwinienne,’ French translat.
aam News,’ May 1873. 1869, p. 132.

84 The Descent of Man. Parr 1,

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, &c., 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, &c.; but who can say at what age this
occurs in our young children? Weseeat least that such powers
are developed in children by imperceptible degrees.

That animals retain their mental individuality is unqyestion-

able. 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,
“T 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 con-
“ tradictory of the utterance of consciousness, and is therefore
“false ; but it is the teaching necessitated by evolutionism, con-
“sequently the hypothesis is a false one.”

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.”7 In Paraguay the Cebus
azare when excited utters at least six distinct sounds, which
excite in other monk-ys similar emotions.*® The movements of
the features and gestures of monkeys are understood by us, and
they partly understand ours, as Kengger and others declare. It
is a more remarkable fact. that the dog, since being domesticated,
has learnt to bark’? in at least four or five distinct tones.
Although barking is a new art, no doubt the wild parert-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
Aespair, as when shut up; the baying at night; the bark of joy, as

46 The Rey. Dr. J. M‘Canz, ‘ Anti- ‘© Rengger, ibid. s, 45.
Darwinism,’ 1869, p. 13. “8 See my ‘Variation of Ani-

47 quoted in ‘Anthropological Re» mals aud Plants under Domestiea«
riew ’ 1864, p. 158, tion,’ vol, i. p. 27,

Snap. III, Mental Powers. 85

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 par-
ticular attention to the subject, the domestic fowl utters at least
a dozen significant sounds,”

The habitual use of articulate language is, however, peculiar
to man; but he uses, in common with the lower animals, inarti-
culate cries to express his meaning, aided by gestures and the
movements of the muscles of the face." 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 con-
necting definite sounds with definite ideas; for it is certain that
some parrots, which have been taught to speak, connect un-
erringly words with things, and persons with events. The
lower animals differ from man solely in his almost infinitely
larger power of associating together the most diversified

30 ‘Facultés Mentales des Ani-
mauzx,’ tom. ii. 1872, p. 346-349.

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.

52 | have received several detailed
accounts to this effect. Admiral
Sir 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
zertain 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
ts thoy left the room at night, and
never reversed these salutations.
So Sir 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 (say-
ing “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, ‘Facultés 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
Cages,

86 The Des-ent of Man.

Part I,

sounds and ideas; and this obviously depends on the high
development of his mental powers.

As Horne Took, 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 truco instinct, for every language has to be learnt. It differs,
wwever, widely from all ordinary arts, for man has an in-
stinctive 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.*® 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
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 show 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 cducated in the Tyrol, teach
and transmit their new sovig 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. Hens-

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,
m the development of language,
“works both cunsciously and an-
¥ iously; co ly as re-

“gards the immediate end to be
“ attained; unconsciously as regards
“the further consequences of the
* act.”

54 Hon. Daines Barrington in
‘Philosoph. Transactions,’ 1773, p.
262. See also Dureau de la Malle,
in ‘Ann, des. Se. Nat.’ 3rd series.
Zoolog. tom. x. p. 119,

Caap, II, Mental Powers. 87

leigh Wedgwood, the Rev. F. Farrar, and Prof. S: hleicher,® and
the celebrated lectures of Prof. Max Miiller 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, theretore, probable that the imitation of musical
cries by articulate sounds may have given rise to words expres-
sive of various complex emotions. The strong tendency in our
nearest allies, the monkeys, in microcephalous idiots, 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; 7 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),°* 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 pro-
genitor of man must have been more highly developed than in

55 ¢On the Origin of Language,’
by H. Wedgwood, 1866. ‘Chapters

58 Vogt, ‘Mémoire sur les Micro-
céphales,’ 1867, p. 169. With re-

on Language,’ by the Rev. F. W.
Farrar, 1865. These works are
most interesting. See also ‘De la
Phys. et de Varole,’ par Albert
-emoine, 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

spect to savages, I have given some
facts in my ‘ Journal of Researches,’
&c., 1845, p. 206.

57 See clear evidence on this head
in the two works so often quoted,
by Brehm and Rengger.

58 Houzeau gives a very curious
account of his observations on this
subject in his ‘ Facultés Mentales
des Animanx,’ tom. ii., p. 348.

38

The Descent of Man. Parr L

any existing ape, before even the most imperfect form of speech
could have come into use; out 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, wus observed to use her fingers whilst dreaming.*
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 substantiven
and proper names are forgotten.” There is no more improb-
ability in the continued use of the mental and vocal organs
leading to inherited changes in their structure and functions,
than in the case of handwriting, which depends partly on the
form of the hand and partly on the disposition of the mind; and
hand-writing is certainly inherited.*!

Several writers, more especially Prof. Max Miiller,® 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 impossible barrier is formed between
them and man." With respect to animals, I have already

59 See remarks on this head by
Dr. Maudsley, ‘The Physiology and
Pathology of Mind,’ 2nd edit. 1868,
p. 199.

60 Many curious cases have been
recorded. See, for instance, Dr.
Bateman ‘On Aphasia,’ 1870, p. 27,
31, 53, 100, &c, Also, ‘ Inquiries
Concerning the Intellectual Powers,’
by Dr. Abercrombie, 1838, p. 150.

81 «Tne Variation of An‘mals
and Plants under Domestica‘ion,’
vol, ii, p 6,

6? Lectures on ‘Mr. Darwin’s Phi-
losophy of Language,’ 1873.

6s The judgment of a distin-
guished philologist, such as Prof.
Whitney, will have far more weight
on this point than anything that
Ican say. He remarks (‘Oriental
and Linguistic Studies, 1873, p.
297), in speaking of Bleek’s views:
“Because on the grand scale lun-
“ guage is the necessary auxiliary
“ of- thought, indispensable to the
“development of the power of

Curap. IIf. Mental Powers.

89

endeavoured to show that they have this power, at least in a
tude and incipient degree. As far as concerns infants of from
ten to eleven months old, and deaf-mutes, it seems to me in-
credible, 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,“ “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 antenne, 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.® 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

“ thinking, to the distinctness and
“variety and complexity of cogni-
“tions to the full mastery of con-
“ sciousness; therefore he would
“fain make thought absolutely im-
‘* possible without speech, identify-
“ing the faculty with its instru-
“iment. He might just as reason-
“ably assert that the human hand
© saunot act without a tool. With
“ such a doctrine to start from, he
“cannot stop short of Miiller’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) the following aphor-
ism: “There is no thought with-
“ out words, as little as there are
“words without thought.” What
a strange definition must here be
given to the word thought!

64 ¢ Essays on Free-thinking,’ &c.,
1873, p. 82.

85 See some good remarks to this
effect by Dr. Maudsley, ‘The Phy-
siology and l'athology of Mind,
1868, p. 199.

The Lescent of Man.

Parr 1.

go

organs, whicl with long-continued practice might have been
used for speech, although aot thus used, is paralleled by the
case of many birds which possess orguns fitted for singing,
though they never sing. Thus, the nightingale and crow have
vocal organs similarly constructed, these being used by tha
former for diversitied song, and by the latter only fur croaking.”*
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 anything
more definite, considering our ignorance with respect to the
successive stages of development through which each crcature
las passed.

The formation of different languages and of distinct species,
and the proots that both have been developed through a gradual
process, are curiously parallel.’ 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 rudi-
ments, both in languages and in species, is still more remarkable.
The letter m in the word um, means /; so that in the expres-
sion J am,a superfluous and useless rudiment has been retained.
In the spelling also of words, letters often remain as the rudi-
ments 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 arti-
ficially 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. We see variability in every tongue, and new

88 Macgillivray, ‘ Hist. of British
Birds,’ vol. ii, 1839, p. 29. An
excellent observer, Mr. Blackwall,
reroarks that the magpie learns to
pronounce sivgle words, and even
short sentences, more readily than
almost any other British bird; yet,
as he adds, after long and closely
investigating its habits, ne has
sever known it, iu a state of aature,

display any unusual capacity for
imitation. ‘Researches in Zovlogy,’
1834, p. 158.

87 See the very interesting pa-
rallelism between the development
of species and Janguages, given by
Sir C. Lyell in ‘The Geolog. Evi-
dences of the Antiquity of Man,’
1863, chap. xxiii.

“ See remarks to this effect by

Onur. 111, Mental Powers. gl

words are continnally cropping up; but as there is a limit to
the powers of the memory, single words, like whole languages,
gradually become extinct. As Max Miiller® has well re-
marked :—* A struggle for life is constantly going on amongst
“the words and gramumatical forms in each language. Tho
“ better, the shorter, the easier forms are constantly gaining the
“ wpper 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 lan-
guages, 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 Ame-
“rican languages.’ But it is assuredly an error to speak of
any language as an art, in the sense of its having been elabor-
ately and methodically formed. Philologists now admit that
conjugations, declensions, é&c., 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,” 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 special-
isation of organs as the test of perfection. So with languages ;
the most symmetrical and complex ought not to be ranked above
izregular, abbreviated, and bastardised languages, which have

the Rev. F. W. Farrar, in an in- 70 Quoted by C. S. Wake, ‘Chap.
teresting article, entitled ‘Philo- ters on Man,’ 1868, p. 101.
.ogy and Darwinism’ in ‘ Nature,’ 7 Buckland, ‘ridgewater Trea
Varch 24th, 1870, p. 528. tise,’ p. 411,

#9 «Nature,’ Jan. 6th, 1870, p. 2957.

g2 The Descent of Man. Pat L

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.” 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
forra.

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

72 Sce some gool remarks os he J. Lubbock, ‘Origin of Cirilisstion,
vunplification of languages, by Sir 1870, p. 278.

Cap. IIT, Mental Powers. 93

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 arged that their ssthetic
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 land-
scape, 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 *
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 capri-
cious in their affections, aversions, and sense of beauty. There
is also reason to suspect that they love novelty, for it 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

78 <The Spectator,’ Dec. 4th, 1869, p. 1430.

The Descent of Man.

Part I.

94

words in their languages to express such an idea. 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® has remarked, “Some explan-
“ation 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 aro
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.”” But until

7™4 See an excellent article on this
subject by the Rev. F. W. Farrar,
in the ‘Anthropological Review,’
Aug. 1864, p. ccexvii. For further
facts see Sir J. Lubbock, ‘Pre-
historic Times,’ 2nd edit. 1869, p.
564; and especially the chapters on
Religion in his ‘Origin of Uivilisa-
tion,’ 1870.

75 <The Worship of Animals and
Plants,’ in the ‘ Fortnightly Review,’
Oct. 1, 1869, p. 422.

76 ‘Tylor, ‘Karly History of Man-
kind,’ 1865, p. 6. See also the
three striking chapters on the De-
velopment of Religion, in Lubbock’s
‘Origin of Civilisation,’ 1870. Ina
ike manner Mr. Herbert Spencer,
in his ingenious essay in the ‘ Fort-
nightly Review’ (May Ist, 1870,
p. 530), accounts tor 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 power-
ful, 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 aud ruder stage, when

vue, JI. Mental Powers. 95

the faculties of imagination, curiosity, reason, &c., had been
tairly 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 occa-
sionally 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 strung sense of dependence,” fear,
reverence, gratitude, hope for the future, and perhaps other
elements. No being could experience so complex an emotion

anything which manifests power or 77 See an able article on the
movement is thought to be endowed ‘ Physical Elements of Religion,’ by
with some form of life, and with Mr. L. Owen Pike, in ‘ Anthropo'og,
mental faculties analogous to our Review,’ April, 1870, p. Lxiii,

owo, ~

96 The Descent of Man. Parr 1

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.7®

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
nis 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, &c.—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™ 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
sonsequences of our highest faculties may be compared with the
incidental and occasioual mistakes of the instincts of the lower
animals.

78 ‘Religion, Moral, &., der Dar- 79 «Prehistoric Times,’ 2nd_ edit.
win’schen Art-Lehre,’ 1869, 5. 53. p. 571, In this work (p. 571)
It is said (Dr. W. Lauder Lindsay, there will be found an excellent
*Journal of Mental Science,’ 1871, account of the many strange and
p. 43), that Bacon Icng age, and tne capricious customs of savages,
poet Buras, held the same aotion,

Cap lV

Moral Sense. 97

CHAPTER IV.

ComMPaRIsOoN oF THE MenTAL Powers or MAN AND THR
Lower ANIMAL8—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 vonduct—Transmission of moral teudencies—Summary.

I ruuty subscribe to the judgment of those writers’ 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? 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 hesita-
tion 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 ?”

This great question has been discussed by many writers‘ of
consummate ability ; and my sole excuse for touching on it, is
the impossibility of here passing it over; and because, as far as ]
know, no one has approached it exclusively from the side of
natural history. The investigation possesses, also, some in-

1 See, for instance, on this subject,
Quatrefages, ‘Unité de i’Espéce
Humaine,’ 1861, p. 21, &c.

2 ¢ Dissertation on Ethical Philo-
sophy,’ 1837, p. 231, &e..

3 ‘Metaphysics of Ethics,’ trans-
fated by J. W. Semple, Edinburgh,
1826, p. 136.

4 Mr. Bain gives a list (‘ Mental

8

and Moral Science,’ 1868, p. 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.

1

The Descent of Man. Part I.

98

dependent interest, as an attempt to see how far the study of
the lower animals throws light un 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
wel] marked social instincts,° the parental and filial affections
being here included, would inevitably acquire a moral sense or
fonscience, 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 mvariably 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

5 Sir B. Brodie, afte: observing
that man is a social animal (‘ Psy-
chological Enqutries,’ 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. 8. Miil speaks, in
his celebrated work, ‘ Utilitarian-
ism,’ (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
“ yeferred to, the moral faculty, if
“not a part of our nature, is
“a natural out-growth from it;
“capable, like thera, in a certain
* small degree of springing up spon-
“ taneously.” But is opposition to

all this, he also remarks, “if, as is
“ my own belief, the moral feelings
“are not innate, but acquired, they
“are not for that reason less natu-
“yal.” It is with hesitation that I
venture to differ at all trom 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 a¢-
quired by each individual during
his lifetime. On the general theory
of evolution this is at least ex-
tremely 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.

Oaxz. IV, Moral Sense. 99

behind it a very vivid impression. It is clear that many in-
stinctive desires, such as that of hunger, are in their nature of
short duration; and after being satisfied, are not readily or
vividly recalled. Zhirdly, 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 how-
ever 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 in-
stinct, together with sympathy, is, like any other instinct, greatly
strengthened by hahit, and so consequently would be obedience
to the wishes and judgment of the community. These several
subordinate propositions must now he 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 samé moral sense as ours. In the same
manner as various animals have some sense of beauty, thovgh
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.®

® Mr. H. Sidgwick remarks, in
an able discussion on this subject
(the ‘Academy,’ June 15th, 1872,
(p. 231), “a superior bee, we may
“ feel sure, would aspire to a milder
“ solution of the population ques-
“tion.” Judging, however, trom
the habits of many or most savages,
man solves the problem by fzmale
infanticide, polyandry and promis-
cuous intercourse; therefore it may
well be doubted wuether it would
te by a milder method. Miss
Cobbe, in comm<nting (‘ Darwinism

Nevertheless, the bee, or any

in Morals,’ ‘Theological Review,’
April, 1872, p. 188-191) on the
same illustration, says, the prin-
ciples 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
ot’ 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 goss so far as
to say that if the theory of ethics
advocated in this chapter were ever

1000 The Descent of Man. Parr I.

other social animal, would gain in our supposed case, as it
appears to me, soine feeling of right or wrong, or a conscience,
For each iidividuai 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, dissatis-
faction, 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.

Sociubility.—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, &c., are when separated from
their companions, and what strong mutual affection the two
fcrmer 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 ou
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, 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* generally to be the females. The leader

generally accepted, “I cannot but earth is not held by many personz
“believe that in the hour of their on sc weak a tenure.

“triumph would be sounded the * «Die Darwin’sche Theorie,’ s.
& knell of the virtue of mankind!” 101.

It is to be hoped that the belief in ® Mr. R. Brown tp ‘ Proc. Zoolog

the permanence of virtue on this Src.’ 1868, p. 409.

Guar. IV. Moral Sense. 101

of a troop of monkeys acts as the sentinel, and utters cries
expressive both of danger and of safety.® 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 grisen-viridis has rushed through a thorny
brake, each monkey stretcnes itself on a branch, and another
monkey sitting by, “conscienticusly” 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, é&c.; 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 bisonsin 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—tne dogs being too much astonished to make an attack.
J 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,

9 Brehm, ‘Thierlehen,’ 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 evilence of Alvarez, whose ob-
servations Brehm thinks quite trust-
worthy. For the cases of the old
male baboons attacking the dogs,
see s. 79; and with respect to the
eagle, s. 56

102 The Descent of Man. Parr I,

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.”

It is certain that associated animals have a feeling of love for
each other, which is not felt Ey uwon-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," states that his macaws, which lived free in Norfolk,
took “an extravagant interest” in a pair with a nest; and when-
ever the female left it, she was surrounded by a troop “ scream-
“ing horribie acclamations in her honour.” It is often difficult
to judge whether animals bave 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; ap-
parently, 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 alinost 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 con-
duct 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.” j

Many animals, however, certainly sympathise with each other’s
distress or danger. This is the case even with birds. Capt.
Stansbury * found ona 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

10 Mr. Belt gives the case ofa
spider-monkey (Ateles) in Nicara-
gua, 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 re-
tained 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 cr three together.
‘The Naturalist in Nivaragna’ 1874.
p. 138,

1 Annals and Mag. of Nat. Hist.,’
November, 1868, p. 382.

2 Sir J. Lubbock, ‘ Prehistoric
Times,’ 2nd edit. p. 446.

'S 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 shove by hall
a dozen old birds

Unap. [V, Moral Sense. 103

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 develop-
ment of any special instinct." 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
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 '* 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” 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 faith-
ful to his driver or keeper, and probably considers him as the

M As Mr. Bain states, “ effective 16 <De VEspéce et de la Classe,
“ aid to a sufferer springs from sym- 1869, p. 97.
“ pathy proper :” ‘ Mental and Moral 7 «Die Darwin’sche Art-Lehre,
Science,’ 1868, p. 245. 1869, ». Sb.

1 +Thievleben, B. i. s. 85.

104 The Descent of Man. Pari L

leader of the herd. Dr. Hocker 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.”

Allanimals 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'* 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 8.
Africa, says,° that they cannot endure even a momentary separa-
tion 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 assidu-
ously for those who, by grazing apart, shew a self-reliant dis-
position, 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 per-
forming 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

'8 See also Hooker’s ‘ Himalayan 70 See his extremely interesting
Journals,’ vol. ii., 1854, p. 333. paper on ‘Gregariousness in Cattle,

Brehm, ‘ Thierleben,’ B, i. s. and in Man,’ ‘ Macmiilan’s Mag.’ Feb,
76, 1871. uv 352

Cnav, IV, Moral Sense. 10§

a strong feeling cf 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 erro-
neous.” 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 uncomfort-
able 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 attri-
buted 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 cf the
social instincts, we know not the steps by which they have
heen gained; but we may infer that it has been to a large
extent through natural selection. So it has almost certainly

Part L

106

The Descent of Man.

been with the unusnal and opposite feeling of hatred between
the nearest relations, as with the worker-bees which kill their
brother-drones, and with the quéen-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 en-
“ during 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.”
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 sur-
prising 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.

21 See the first and striking
chapter in Auam Smith’s ‘Theory
of Moral Sentiments.’ Also Mr.
Bain’s ‘Mental and Moral Science,’
3868, p. 244, and 275-282, Mr.
Bain states, that ‘“‘sympathy is, in-
“directly, a source of pleasure to
“ the sympathiser ;” and he accounts
‘or this through reciprocity. He
emarks that “the person benefited,

With

“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 plea-
sure, in the same manner as th¢
exercise, as before remarked, of al
most evezy other instinct.

Caar. IV. Moral Sense. 107

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 kininess 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 commu-
nities, which included the greatest number of the most sympa-
thetic 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, there-
fore, 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 conquer-
ing 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 conld

108 The Descent of Man. Parr I,

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. Neverthe-
less, the migratory instinct is so powerful, that late in the autumn
swallows, house-martins, and swifts frequently desert their
tonder young, leaving them to perish miserably in their nests.”

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,
mey 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 wu sociul avimal.—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 con-
tinement 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

2 This fact, the Rev. L. Jenyns hatched. Many birds, not yet old

states (see his edition of ‘White’s
Nat. Hist. of Selborne,’ 1853, p.
204) was first recorded by the illus-
trious Jenner, in ‘Phil. Transact.’
1824, and has since been confirmed
5y 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 ou the point of being
hatched, and three, eggs not nearly

enough for « prolonged flight, are
likewise deserted and left behind.
See Blackwall, ‘Researches in Zoo-
logy,’ 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. Simi«
lar cases have been observed in
Canada by Mr. Adams; ‘ Pop,
Science Review,’ July 1873, p
283,

Cuap. IV. Moral Sense.

109
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 ;* 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 isa social animal,
it is almost certain that he would inherit a tendency to bo
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,” 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.” Conse-
quently 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

23 Hume remarks (‘An Enquiry “ of the former . . . communicates

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 in-
* different to us. but that the view

“a secret joy; the appearance of
“the latter... throws a melan-
“choly damp over the imagina
“ tion.”

24 ¢Mental and Moral Sciene2
1868, p. 254

{10 The Descent of Man. Paat L

of his fellow-mer, 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 Sociul 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 focd from
hunger ?

It is evident in the first place, that with mankind the instine-
tive 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
civilized man, or even boy, who never before risked his life for
another, but full of courage and sympathy, has diregarded
the instinct of self-preservation, and plunged at once into a
torrent to save a drowning man, though astranger. 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. Sucn
actions as the above appear to be the simple result of the greater
strength of the social or maternal instincts than that of any
other instinct or motive; for they are performed too instan-
taneously 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 foree himself to run any such risk, perhaps not even for his
own child.

1 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

nay, IV. Moral Sense. 111

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.* As far as exalted motives aro
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,* 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

25 T refer here to the distinction
setween what has been called ma-
terial and formal morality. I am
glad to find that Prof. Huxley (‘Cri-
tiques and Addresses,’ 1873, p. 287)
takes the same view on this subject
as I do. Mr. Leslie Stephen re-
marks (‘ Essays on Freethinking and
Plain Speaking,’ 1873, p. 83), “ the
“ metaphysical distinction between

“material and formal morality is
“as irrelevant as other such dis-
“ tinctions.”

26 | 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 (‘ Jourpal
of Researches,’ 1845, p. 108),

112 The Descent of Man. Part I,

motives, or impulsively through instinct, or from the effects ol
slowly-gained habit.

But to return to our more immediate subject. Although
some instincts are more powerful than others, and thus lead to cor-
responding 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, &c. 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 bis 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 cthers think of us,—of their imagined approbation or
disapprobation; and this all follows from sympathy, a funda-
mental 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. ‘he
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 pos-
session 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.”

7 Enmity or hatred seems alse perhaps more so than any other
to be a higaly persistent "ug, that cam be named. Envy is de:

Moral Sense.

Juar, TV. 113

Aman 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
‘nstinct 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 con-
gregate 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 persis-
tent 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.

fined as hatred of another for some
excellence or success; and Bacon
insists (Essay ix.), “Of all other

had done him an injury and had
become his enemy. Nor is it pro-
bable that the primitive conscience

“affections envy is the most im-
“ portune 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 per-
aistent 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
uy one to transfer such feelings to
iny member of the same tribe if he

9

would reproach a man for injuring
his enemy: rather it would re-
proach him, if he had not revenged
himself. To do good in return for
evil, to love your euemy, is a height
ot morality to which it may be
doubted whether the social instincts
would, by themselves, have ever led
us. It is necessary that these in-
stincts, 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.

114 The Descent of Man. Paar I,

At the moment of action, man will no doubt be apt to follow
the stronger impulse; and though this may occasionally
prompt hira 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 bis 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. JFiven 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,” that a native on his farm, after
losing one of his wives from disease, came and said that “ he was

*? «Insanity in Relation to Law;’ Ontario, United States, 1871, p. 14.

Onap {V. Moral Sense. 115

“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 in-
“ exorable, 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.
tlow 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 im the
“ greatest abhorrence, in this agreeing exactly with certain
“ tribes of North America. When the question is put in cither
“ 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.” 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 con-
science. On the whole it is intelligible, that a man urged by
s0 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-conimand, that his desires and passions
will at last yield instantly and withcut 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-
eommand may, like other habits, be inherited. Thus at last man

2 KR. B. Tylor in ‘Contemporary Review,’ April, 1873, p. 707.

116 The Descent of Man. Part 1

comes to feel, through acquired and perhaps inherited habit, that
it is best for him to obey his more persistent impulses. The
imperious word ouyit 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; 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
tree from self-reproach, or at least of anxiety, it is almost neces-
sary 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
sttpervenes.

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 taculty in mankind. The virtues
which must be practised, at least generally, by rude men, so

* Dr. Prosper Despine, in his many curious cases of the worst

Psy chologie Naturelle,’ 1868 (tom. criminals, who apparently have been
p. 243; tom. ii, p 169) gives entirely destitute of conscience.

Cuar IV. Moral Sense.

117
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, d&c., were common; consequently such
crimes within the limits of the same tribe “are branded with
“everlasting infamy ;”*! 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,” and has
met with no reproach ; but infanticide, especially of females, has
been thought to be gvod for the tribe, or at least not injurious.
Suicide during former times was not generally considered as a
crime,® 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, is a great crime; yet it was not so regarded until quite
recently, even by the most civilized 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

31 See an able article in the
‘North British Review,’ 1867, p.
395. See also Mr. W. Bagehot’s
articles on the Importance of Obe-
dience and Coherence to Primitive
Man, in the ‘Fortnightly Review,’
1867, p. 529, and 1868, p. 457, &e.

8 The fullest account which I
have met with is by Dr. Gerland, in
his ‘Ueber dan Aussterben der
Naturvélker,’ 1868; but I shall
aave to recur to the subject of
wnfanticide in a future chapter.

33 See the very interesting discus-
sicn 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, Muller, as quoted by Hou-
zeau, ‘Les Facultés Mentales,’ 4c.,
tom. ii. p. 136.

34 See Mr. Bagehot, ‘ Physics ane
Politics,’ 1872, p. 72.

118 The Descent of Man. Parr 1

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** 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

35 See, for instance, Mr. Hamilton’s account of the Kaffirs, ‘ Anthro
pological Review,’ 1870, ~ xv.

Moral Sense.

Onar, TV,

119

is no reproach with savages. Utter licentiousness, and ur-
natural crimes, prevail to an astounding extent.*® 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’ 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,® 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, &c. 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,® because some authors have recently taken a high view
of their moral nature, or have attributed most of their crimes to
mistaken benevolence.” These authors uppear to rest their

36 Mr. M’lennan
“Primitive Marriage,’

has_ given 38 «Embassy to China,’ vol. ii. p,
1865, p. 348

*76) a good collection of facts on
this head.

37 Lecky, ‘History of European
Morals,’ vol, i. 1869, p, 109,

39 See on this subject copious
evidence in Chap. vii. of Sir J. Lub-
bock, ‘ Origin of Civilisation,’ 1870.
40 For instance Lecky, ‘Hist
European Morals,’ vol, i. p, 124.

120 The Descent of Man. Part 1

conclusion on savages possessing those virtues which are ser-
viceabie, 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! 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 1 have consulted, with a few excep-
tions,” 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.

Tn the case of the lower animals it seems much more appro-
priate to speak of their social instincts, as having been developed

“ This term 3s used in an able

“ness extra-regarding impulse, di-
article in the ‘ Westminster Review,’

“rected towards something that is

Oct. 1869, p. 498. For the “ Greatest
“happiness principle,” see J.S. Mill,
‘Utilitarianism,’ p. 17.

42 Mill recognises (‘System of
Logic,’ vol. ii., p. 422) in the clearest
manner, that actions may be per-
formed through habit without the
anticipation of pleasure. Mr. H.
Sidgwick also, in his Essay on
Pleasure and Desire (‘The Con-
temporary Review,’ April 1872, p.
671), remarks: “To sum up, in
* contravention of the doctrine that
“ our conscious active impulses are
“ always directed towards the pro-
‘duction of agreeable sensations in
“ ourselves, I would riaintamn that
‘‘ we find everywhere .n conscious-

* 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 accept-
ance 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.

Cua, IV, Moral Sense. T21

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
“ oreatest happiness principle” will have become a most im-
portant 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, bas 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 judg-
ment will not rarely err from ignorance and weak powers ‘uf

122 The Descent of Man. Parr

reason’ ng. Hence the strangest customs and superstitions, in
complete opposition to the true welfare and happiness of man-
kind, 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 ke difficult to distinguish
between the remorse felt by a Hindov 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 trikes than by
others ;* 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 bis early
condition.

Notwithstanding 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, ma-
tured 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 reuched,
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

‘3 Good instances are given by in his ‘Contributions to the Theory
Mr. Wallace in ‘Scientific Opinion,’ of Natural Selection,’ 1870, p. 33.
Sept. 15, 1869; and more fully

Ouar. LY. Moral Sense. 122

v

sr 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. Ilow
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. Assoon 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
op'nion.

The highest possible stage in moral culture is when we re-
cognise 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.”** 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.”

Our great philosopher, Herbert Spencer, has recently explained
his views on the moral sense. He says,** “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 noapparent 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 coinei-
dence for the tendency occurring in two or three members of

44 Tennyson, ‘ Idyils of the King, Aurelius was born a.D. 121,
p. 244. 4° Letter to Mr. Mill in Baiu’s
48 ‘The Thoughts of the Emperor ‘Mental and Moral Science,’ 1863,
M. Aurelius Antoninus,’ Eng. trans- p, 722.
sat., Zud edit, 1869, p. 112, Marcus

124 The Descent of Man. Parr 1

the same family. If bad tendencies are transmitted, it is pro-
bable that good ones are likewise transmitted. That the stats
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 destraction of the
“ moral sense being often one of the earliest symptoms of mental
“ derangement ;”* and insanity is notoriously often inherited.
Except through the principle of the transmission of moral ten-
dencies, 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,
&c., 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.
T have not met with any evidence in support of the transmission
of superstitious customs or senseless habits, although in itself it
is perbaps not less probable than that animals should acquire
inherited tastes for cértain 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, und 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,

*" Mandsley, ‘Bedy and Mind,’ 1870, p. 60.

Cuap, [V, Summary. 125

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.”

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
atrouger impulses or desires. This, as Mr. Galton 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 im-
pression 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 he 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 fightmg or for breaking open
nuts, yet that the thought of fashioning a stone into a tool was

4@ A writer in the ‘North British
Review’ (July 1869, p. 531), well
eapable of forraing a sound judg-
ment, expresses himself strongly in
favour of this conclusion. Mr.
Lecky (* Hist. of Morals,’ vol. i. p.
143) seems to a certain extent to

coincide therein.

49 See his remarkable work ov
‘Hereditary Genins,’ 1869, p. 349,
The Duke of Argyll (‘ Primeval
Man,’ 1869, p. 188) has some geod
remarks on the contest in man’s
nature between right and wrong.

126 The Descent of Man. Parr |

quite beyond his scope. Still less, as he would admit, could he
follow out a train of metaphysical reasoning, or solve a mathe-
matical problem, or reflect on God, or admire a grand natural
secne. 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 per-
ceptions 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 acknow-
ledge 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, &c., 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 sce in the domestic dog compared
with the wolf or jackal. If it could ke proved that certain high
mental powers, such as the formation of general concepts, self-con-
sciousness, &c., 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 intel-
lectual 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 ““—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.

% ‘The Thoughts of Marcus Aurelius,’ &., p. 139.

Cuar. V, Intellectual Faculties. 127

Tn 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 evolu-
tion 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 Moray
FACULTIES DURING PRIMEVAL AND CIVILISED TIMES.

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

Tue subjects to be discussed in this chapter are of the highest
jaterest, but are treated by me in an imperfect and fragmentary
manner. Mr. Wallace, in an admirable paper before referred to,'
argues that man, after he had partially acquired those intel-
tectual 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 ta
exist

‘ ¢ Anthropological Review,’ May 1864, p. cl vin,

128 The Descent of Man. Parr 1,

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 ina much higher
degree on the arts which are there practised. Asa tribe increases
and is victorious, it is often still further increased by the ab-
sorption of other tribes? 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;$ but their success was pro-
bably 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. Relies 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, whict
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 con-
elusion is sufficient for our purpose. Undoubtedly it would
be interesting to trace the development of each separate faculty

? After a time the members or 1861, p. 131), that they are the co«
‘tribes which are absorbed into descendants of the same ancestors.

another tribe assume, as Sir Henry 3 Morlot, ‘Soc. Vaud. Se. Nat’
Maine remarks (‘Ancient Law,’ 1860, v. 294.

Cap. V. Moral Faculties. 129

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 moro
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‘ 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 pregenitors 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

4 I have given instan: +e in my ‘ Variation of Animals under Domesticw
tion, vol. ii. p. 196.

10

130 The Descent of Man. Parr

acquired by the progenitors of wan in a similar manner, namely,
through natural selection, aided by inherited habit. When two
tribes of primeval ian, 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
gonquer 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 undis-
ciplined hordes follows chiefly from the confidence which each
man feels in his comrades. Obedience, as Mr. Bagehot has well
shewn,’ 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 ex-
cellence 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 thé number of men
gifted with such virtues, or that the standard of their excellence,
could be increased through natural selection, that is, by the
gurvival of the fittest; for we are not here speaking of one tribe
peing 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

5 See a remarkable series of arti- April 1, 1868; July 1, 1869, sines
eles on ‘ Physics and Politics’ in tha — separate!y published.

‘Fortnightly Review,’ Nov. 1867;

Onap. V. Moral Faculties. i31

foresight of the members became improved, each man would
soon learn that if he aided his fellow-men, he would commonly
receive aid inreturm. 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,
noreover, followed during many generations probably tend to
be inherited.

But another and much more powerful stimulus to the de-
velopment 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 appre-
ciate encouragement, praise, and blame. The rudest savages
feel the sentiment of glory, as they clearly show by preserving
the trophies of their prowess, by their habit of excessive boasting,
and even by the extreme care which they take of their per-
sonal appearance and decorations; for unless they regarded the
upinion 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,® 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

Mr, Wallace gives eases in of Natural Selection, 1870, p
hia ‘Contributions to the Theory 354.

132 The Descent of Man. Past L

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, &c., 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 ur 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 every-
where 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,’ “the greatest part of mankind has never shewn a

7 ‘Ancient Law,’ 1861, ;. 22. nightly Review,’ April 1, 1868, p
for Mr Bagehot’s remarks, ‘Fort- 452.

uae, V. Civilised Nations.

133

“particle of desire that its civil institutions should be im-
“ proved.” 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 else-
where shewn,® 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,? and previously by Mr. Wallace and Mr. Galton. 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

8 ¢The Variation of Animals and
Plants under Domestication,’ vol. i,
p. 809.

® ¢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
deen discussed in the §Q. Journal of
Science,’ 1869, p. 152, and by Mr.
Lawson Tait in the ‘Dublin Q.
Journal of Medical Science,’ Feb.

1869, and by Mr. E. Ray Lankester
in his ‘Comparative Longevity,’
1870, p. 128. Similar views ap-
peared previously in the ‘ Austra+
lasian,’ July 13, 1867. I have
borrowed ideas from several of these
writers.

10 For Mr. Wallace, see ‘ Anthro
polog. Review,’ as before cited. Mr.
Galton in ‘Macmillan’s Magazine,’
Aug. 1865, p. 318; also his greaf
work, ‘ Hereditary Genius,’ 1870,

134 The Descent of Man. Paxt 1.

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 frcm a weak constitution would
formerly have succumbed to small-pox. Thus the weak members
of civilised soc.eties 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 oue 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 sub-
sequently 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 deteriora-
tion 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 con-
tingent 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."

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 su-
periority. 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,

" Prof, H. Fick (‘Einfluss der on this head, and on other such

Naturwissenschaft auf dag Recht,’ points.
Vane, 1872) has some zood remarks

Cirar. V. Civilised Nations, 135

aud will be likely to marry earlier, and leave a larger number of
offspring to inherit their inferior constitutions. But the in-
heritance 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, whv have nat 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
oecurs, 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 worth-
less 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 genera-
tion 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 marrymg
heiresses. But the daughters of parents who have produced
single children, are themselves, as Mr. Galton” 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
eny kind.

Although civilisation thus checks in many ways the action of

12 + Hereditary Genius,’ 1870, pp. 132-140,

136 The Lescent of Man. Part L

natural selection, it apparently favours the better development
of the body, by means of good food and the freedom from occa-
sional hardships. This may be inferred from civilised men
having been found, wherever compared, to be physically
stronger than savages."* They appear also to have equal powers
of endurance, as has been proved in many adventurous ex-
peditions. Even the great luxury of the rich can be but little
detrimenta’ 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."

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 multiplica-
tion 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. My. 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.” 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 pre-
servation of strongly-marked and rare anomalies, that leads to
the advancement of a species." so it will be with the intellectual
faculties, since the somewhat abler men in each grade of society

13 Quatrefages, ‘Revue des Cemirs_ 1870, p. 115,
Scientifiques,’ 1867-68, p. 659. 18 «Hereditary Genius,’ 1870, p,
M4 See the 4fth and sixth columns, 330.
compiled from good authorities, in 18 ¢Origin of Species’ (fifth edi-
the table given in Mr, E. R. Lan- tion, 1869), p. 104,
xester’s ‘Comparative Longevity,’

UHAP. Vv. Civilised Nations. 137

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 intel-
lectual 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” — emigrate to
newly-settled countries, where they prove useful pioneers. In-
temperance 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.’ 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, aud an increased number of fairly good men are con-
cerned, 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

1) ‘Hereditary Genius,’ 1870, p. Neisou’s ‘ Vital Statistics.’ In ree
347. gard to profligacy, see Dr. Farr,

18 E. Ray Lankester, ‘Compara- ‘Influence of Marriage on Mor-
sive Longevity,’ 1870, p. 115. The tality,’ ‘Nat. Assoc. for the Promo
sable of the intemperate is from tion of Soc.al Science,’ 1858,

138 Parr I.

The Descent of Man.

of our sy1apathies 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, namely, the fact that the very
poor and reckless, who are often degraded by vice, almost invari-
ably 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,” they pro-
duce many more children. The children, moreover, that are
born 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
‘yabbits: the frugal, foreseeing, self-respecting, ambitious Scot,
“stern in his morality, spiritual in his faith, sagacious and dis-
“ciplined 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 pre-
“ vailed—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,” that at all

19 ¢Fraser’s Magazine,’ Sept,

title of ‘Fecundity, Fertility, and
1868, p. 353. ‘Macmillan’s Maga-

Sterility,’ 1871. See, also, Mr.

zine, Aug. 1865, p. 318. The Rev.
F. W. Farrar (‘Fraser’s Mag.’ Aug.
1870, p. 26+) takes a different view,

20 «On the Laws of the Fertility
of Women,’ in ‘Transact. Royal
Soc.’ Edinburgh, vol. xxiv. p. 287;
now published separately ander the

Galton, ‘Hereditary Genius,’ pp.
352-357, for observations to the
above effect.

21 ¢Tenth Annual Report of
Births, Deaths, &c., in Scotland,
‘867, p, xxix.

umap. V. Civilised Nations.

139

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 re-
turns 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,’* 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 corafort, 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 ina much larger
proportion than the married: for instance, out of every 1000
unmarried men, between the ages of twenty and thity, 11:3
annually died, whilst of the married only 65 died.% 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.** 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 constitu-

% These quotations are taker.
from our highest authority on such

from the same striking paper.
24 | have taken the mean of the

questions, namely, Dr. Farr, in his
paper ‘Qn the Influence of Mar-
riage on the Mortality of the French
People,’ read before the Nat. Assoc.
for the Promotion of Social Science,
1858.

23 Dr. Farr, ibid. The quota-
tions given below are extracted

quinquennial means, given in ‘The
Tenth Annual Report of Births,
Deaths, &c., in Scotland,’ 1867.
The quotation from Dr. Stark is
copied from an article in the ‘ Daily
News,’ Oct. 17th, 1868, which Dr.
Fary considers very carefully write
ten.

140 The Descent of Man. Pagt I,

tion, 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
cf men, who with weak health during youth did not marry, and
yet have survived to old age, though remaining weak, and there-
fore always with a lessened chance of life or of marrying. Thore
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 mor-
tality; 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. 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 increas-
ing 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 the 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

35 Dr. Duncan remarks (‘Fecund- “ from the unmarried side to the
ity, Fertility,’ &c., 1871, p. 334) on + “ married, leaving the unmarried
this subject; “At every age the ‘columns crowded with the sickly
“healthy and beautiful go over ‘and unfortunate.”

Crap V. a1

Civilised Nations.

existed,?> 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 assump-
tion, 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 acta
enly tentatively. Individuals and races may have acquired cer-
tain 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.” 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, thongh they owe much to the written works of that
‘wonderful people.

Who can positively say why the Spanish nation, so dominant
at one tine, has been distanced in the race. The awakening of
the nati.us of Europe from the dark ages is a still more perplex-
ing prob'em. 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; 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 cen-
turies 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 un-
paralleled rate.

2@ See the ingenious and original
argument on this subject by Mr.
Galton, ‘Hereditary Genius,’ pp.
340-342,

37 Mr. Greg, ‘Frase1’s Magazine,’
Sept. 1868, p. 357.

2% ‘Heroditary Genius,’ 1870, pp.
357-359, The Rev. F. W. Farrar
‘Fraser’s Mag.’ Aug. 1870, p.

257) advances arguments on the
other side,. Sir C. Lyell had already
(‘Principles of Geology,’ vol. a
1868, p. 489) in a striking passage
called attention to the evil influenc?
of the Holy Inquisition in having,
through selection, lowered the gene
ral standard of intelligence in Eu
Tope.

142 The Descent of Man. Parr £

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 ener-
getic, 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. Looking to the
distant future, I do not think that the Rev. Mr. Zincke takes an
exaggerated view when he says: “ 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 favourcd
uations.

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.
Bnt 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 sub-
jected 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
hy a few wandering savages, it might be argued that the struggle
for existence had not been sufficiently severe to force man up-
wards 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

*2 Mr. Galton, ‘Macmillan’s and National Life,’ Dec. 1869, p. 184.

Magazine, August, 1865, p, 325. 30 «Last Winter im the United
See also, ‘Nature, ‘Or Darwinism States,’ 1868, p. 29.

Cuap. V. Civilised Nations. 143

demands many favourable concurrent circumstances; but it may

well be doubted whether the most favourable would have sufficed,
had not the rate of increaso 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 con-
ditions of life are very easy. With highly civilised nations con-

tinued 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 Jaws, 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 apprecia-

tion 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.»

On the evidence that all civilised nations were ounce barharous.—
The present subject has been treated in so full and admirable a
manner by Sir J. Lubbock,” 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 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
gsumewhat more degraded; but it would be difficult to prove

» | am much indebted to Mr. 32 <On the Origin of Civilisation,
yohn Morley for some good criti- ‘Proc. Ethnological Soc.’ Nov. 26
tisms on this subject: see, alsu, 1867.
roca, ‘ Les Sélections,’ ‘Revue d’An- 33 ¢ Primeval Man,’ 1849.
thropologie,’ 1872.

Part I,

144 The Descent of Man.

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,
é&e.; and on the other side, of proofs that savages are inde-
rendently 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, &c., 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.”** 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® 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 mono-
gamous? ‘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 right-
eousness—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

4 <Royal Institution of Great
Britain,’ March 15, 1867. Aiso,
‘Researches into the Early History
of Mankind,’ 1865.

35 ¢ Primitive Marriage,’ 1865.
See, likewise, an excellent article,
evidently by the same author, in
the ‘North Buitish Review,’ July,
1869. Also. Mv. I. H. Morgen,

‘A Conject tral Solution of the
Origin of the Class, Svstem of
Relationship,’ in ‘ Proc, American
Acad.. of Sciences,’ vol. vii, Feb,
1868. Prof. Schaaffhausen (‘ An-
thropolog. Review,’ Oct. 1869, p.
373) remarks on “the vestiges of
“human sacrifices found both in
“Homer and the Old Iestament.”

Cuar. V Nations. 145

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®* 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 cof 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 ;*”
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 in-
habitants 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 abori-
ginally 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.

36 Sir J. Lubbock, ‘Prehistoric edit., 1870.
Times,’ 2nd edit. 1869, chap. xv. 37 Dr, F, Miller has made some
and xvi. ef passim, See also the good remarks to this effect in the
excellent 9th chapter in Tylor’s ‘Reise der Novara: Anthropoleg,
Karly History of Mankind,’ 2nd Theil,’ Abtheil. iii, 1868, », 127,

11

146 The Descent of Man. Paet L

CHAPTER VI.
On THE AFFINITIES AND GENEALOGY OF MAN.

Position of man in the animal series—The natural system genealogical—
Adaptive characters ot slight value—Various small points of resem-
blance between man and the Quadrumana—Rank of man in the natural
system—Birthplace and antiquity of man—Absence of fossil connecting-
Jinks—-Lower stages in the genealogy of man, as inferred, firstly trom
his affimties and secondly from his structure—-Early androgynous con-
dition 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 natu-
ralists maintain, and although we must grant that the differ-
ence between them is immense in mental power, yet the facts
given in the earlier chapters appear to declare, in the plaincst
manner, that man is descended from some lower form, notwith-
standing that connecting-links have not hitherto been dis-
covered.

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 expused to struggle for existence, and con-
sequently 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 embryo-
logical development. He retains many rudimentary and useless
structures, which no doubt were once serviceabie. 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 Lad been wholly different from that of all other
animals, these various appearances would be mere empty
deceptions; but such an admission is incredible. These appear-
ances, 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,

ue

Cuap. VIL. Affinities and Genealogy.

147

end the Vegetable, thus giving to man a separate kingdom.’
Spiritual powers cannot be compared or classed by the natu-
ralist: 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
und 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 bas shewn, a large volume; I may, however, briefly
specify afew 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. ‘Lhey go out to battle in regular bands, and freely
sacrifice their lives for the common weal. They emigrate ac-
cording 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; aud endless similar facts could be given.? On the
whole, the difference in mental power between an ant and a
coccus is immense; yetno one has ever dreamed of placing these
insects in distinct classes, much less in distinct kingdoms. No

1 Isidore Geoftroy St.-Hilaire gives
a detailed account of the position
assigned to man by various natural-
ists in their classifications: ‘ Hist.
Nat. Gén.’ tom, ii. 1859, pp. 140-
189.

2 Some of the most interesting
facts ever pablished on the habits

of ants are given by Mr. Belt, in
in his ‘Naturalist in Nicaragua,’
1874, See also Mr. Moggridge’s
admirable work, ‘Harvesting Ants,’
&c., 1873, also ‘ L’Instinct chez les
Insectes,’ by M. George Pouchet,
‘Revue des Deux Mondes,’ Feb
1870 p. 682.

{48 The Descent of Man. Part 1.

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 mammatian 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 arrange-
ment proved thoroughly artificial? Classifications may, of
course, he based on any character whatever, as on size, colour,
or the element inhabited; but naturalists have long felt a
profound .convietion 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; butif the parent-forms are
related, so will he their descendants, and the two groups to-
gether will form a larger group. The amount of difference
between the several groups—that is the amount of modification
which each has undergone—is expresse] 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 resem-
blance 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

Westwood, ‘Modern Class of Insects,’ vol. ji. 1840, p. 87.

Cuar. VI. Affinities and Genealogy. 149
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 clas-
Bification; 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 con-
ditions) 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 mainmal,
would not aid the species in gaining its food, or for any other
object ; but with man we can see no definite Jimit to the con-
tinued 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 de-
velopment 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 con-
sideration 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, é&c. Recently many of our best naturalists have
recurred to the view first propounded by Linnzeus, so remarkable
for his sagacity, and have placed man in the same Order with
the Quadrumana, under the title of the Primates. ‘The justice ot
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,

150 The Descent of Man. Part L.

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,‘ seals are ranked
as a mere family in the Order of the Carnivora. If man had not
been his awn 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, and
concludes that man in all parts of his organisation 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 ina 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 azd 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 back-
wards, and the lower eyelids wrinkled. The external ears are
surivusly 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 toa great

4 ‘Proc, Zoolog. Soe,’ 1863, p. 4.
5 ¢kvidence as to Mun’s Place in Nature,’ 1863, p. 70, «¢ p sssim.

Cuap., VI. Affinities and Genealogy. £51

length in some species of Semnopithecus;* and in the Bonnet
moukey (Macacus rudiatus) 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’ 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 becume 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 moukeys. But in
Hylobates ayilis the hair on the fore-arm is directed downwards
or towards the wrist in the ordinary manner; and in Z. 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.” *
If the above explanation is correct, as seems probable, the direc-
tion 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

6 Isid. Geofircy, ‘Hist. Nat. Gén.’ Anat, und Phys.’ 1837, s. 51.
tom. ii, 1859, p. 217. ® Quoted by Reade, ‘The Africas
7 ¢Ueber die Richtung der Sketch book,’ vol, i., 1873, p. 152,
Haare,” &c., Muiller’s ‘Archiv fiir

152 The Descent of Man. Pani &

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.®

It must not be supposed that the resemblances between man
and certain apes in the above and many other points—such as in
having a naked forehead, long tresses on the head, &c.—are all
necessarily the result of unbroken inheritance from a common
progenitor, or of subsequent reversion. Many of these resem-
blances are more probably due to analogous variation, which
follows,as I have clsewhere attempted to shew,” 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 in-
heritance; 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,"
divides the Primates into three Sub-orders; namely, the An-
thropide with man alone, the Simiade including monkeys of all
kinds, and the Lemuride with the diversified genera of lemurs,
As far as differences in ceriain 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

» On the hair in Hylobates, see
‘Nat. Hist. of Mammals,’ by C. L.
Martin, 1841, p. 415. Also, Isid.
Geoffroy on the American monkeys
and other kinds, ‘Hist. Nat. Gén.’
vol. ii, 1859, p. 216, 243. Esch-
nicht, ibid. s. 46, 55, 61. Owen,
‘Anat. of Vertebrates,’ vol. iii. p.
619. Wallace, ‘Coniributions to

the Theory of Natural Selection,’
1870, p. 344,

10 “Origin of Species,’ 5th edit,
1869, p. 194, ‘The Variation ct
Animals and Plants under Domesti-
cation,’ vol. ii. 1868, p. 348.

11 ¢ An Introduction to the Classi«
fication of Animals,’ 1869, p, 99.

Cuap. VI.

A finities and Genealogy. 153

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 dif-
ferences in some few points,—that is, to the amount of modifi-
cation 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 Simiade. This family is
divided by almost all naturalists into the Catarhine 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 Platyrhine
group or New World monkeys (including two very distinct
sub-groups), all of which are characterised by diiferently
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 Catarhine or Old World
division ; nor does he resemble the Platyrhines more closely than
the Catarhines in any characters, excepting in a few of not much
importance and apparently of an adaptive nature. Itis 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 Catarhine division.”

The anthropomorphous apes, namely the gorilla, chimpanzee,

-? This is nearly the same classifi-
ation as that provisionally adopted
by Mr. St. George Mivart (‘Tran-
sact. Philosoph. Soe.’ 1867, p. 300),
who, after separating the Lemurida,
divides the remainder of the Pri-
mates into the Homiuide, the Simi-

ade which answer to the Catarhines,
the Cebide, and the Hapalide,—
these two latter groups answering
to the Platyrhines. Mr. Mivart
still abides by the same view; see
‘Nature,’ 1871, p. 481.

154 The Descent of Man. Parr &

orang, and bylobates, are by most’naturalists separated from the
other Old World raonkeys, 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.”
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 such 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
Catarhine 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 consequeuce of the great development of his brain ard his
erect position ; nevertheless, we should bear in mind that he “ is
* but one of several exceptional forms of Primates.”

Every naturalist, who believes in the principle of evolution,
will grant that the two main divisions of the Simiade, namely
the Catarhine and Platyrhine 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 Catarhine
and Platyrhine divisions. Hence the members of this supposed
ancient group would not have been so uniform in their den-
tition, or in the structure of tneir nostrils, as are the existing

13 ¢ Transact, Zeolog. Soc.’ vol vi. ™ Mr. St. G. Mivart, ‘ Transact
1867, p. 214. Phil. Soc.’ 1867, p. 410,

Onar. VI. Affinities und Genealogy. 155

Catarhine monkeys in one way and the Platyrhines in another
way, but would have resembled in this respect the allied Lemu-
ridx, which differ greatly from each other in the form of their
muzzles, and to an extraordinary degree in their dentition.
The Catarhine and Platyrhine 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 Catarhine and
Platyrhine monkeys, other characters in an intermediate con-
dition, and some few, perhaps, distinct from those now found in
either group. And as man from a genealogical point of view
belongs to the Catarhine 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.’
But we must not fall into the error of supposing that the early
progenitor of the whole Simian stock, including man, was iden-
tical with, or even closely resembled, any existing ape or monkey.

On the Birthplace and Antiquity of Mun.—We are naturally
led to enquire, where was the birthplace of man at that stage of
descent when our progenitors diverged from the Catarhine
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 in-
habited by extinct apes closely allied to the gorilla and chim-
panzee; 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” of Lartet, nearly as large as a man,

18 Messrs. Murie and Mivart on his ‘Natiirliche Schdpfungsge-
the Lemuroidea, ‘Transact. Zoolog. schichte,’ 1868, in which he gives

Soe.’ vol. vii. 1869, p. 5. in detail his views on the genealogy
16 Hackel has come to this same of man.
conclusion, See ‘Ueber die Ent- Dr. C. Forsyth Major, ‘Sur les

stehung des Menschengeschlechts,’ Singes Fossiles trouvés en Italie:
im Virchow’s ‘Sammlung. gemein. ‘Soc. Ital. des Se, Nat.’ tom. xv. 1872
wissen. Vortrage,’ 1858, s, 61. Also

156 The Descent of Man. Part 1

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
wan 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
Catarhine 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
iguorant 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 Lemuridaee—between the elephant, and in a more striking
manner between the Ornithorhynchus or Echidna, and a!l 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 anthro-
‘poraorphous apes, as Professor Schaaffhausen has remarked,'®
will no doubt be exterminated. The break between man and his
nearest allies will then be wider, for it will intervene between
faan in a more civilised state, as we may hope, even than the
Caucasian, and some ape as low as a Laboon, instead of as now
between the negro or Australian and the gorilla.

18 © Anthropological Review,’ April, 1867, p. 236.

dua. VI. Affinities and Genealogy. 157

With respect to the absence of fossil remains, serving to
connect man with his ape-like progenitors, no ona will lay much
stress on this fact who reads Sir C. Lyell’s discussion, where
he shews that in all the vertebrate classes the discovery of fossi)
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 Catarhine or Old World
division of the Simiada, 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 Lemuride stand
below and near to the Simiads, and constitute a very distinct
family of the Primates, or, according to Hackel 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,” “ insensibly from the crown aud
“ 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 Simiadze were
originally developed from the progenitors of the existing
Lemuride ; 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 Mar-
supials, but from their early progenitors. The Monotremata are
plainly allied to the Marsupials, forming a third and still lower

19 ¢Elements of Geology,’ 1865, 20 ¢Man’s Place in Nature,’ »
pp. 583--585. ‘Antiquity of Man,’ 105,
1863, p. 145.

158 The Descent of Man. Paur I

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 groap representatives of which have been preserved
in Australia through some favourable concurrence of circum-
stances. 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. Hickel’s works.?! 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 fish-
like animal. The belief that animals so distinct as a monkey,
an elephant, a humming-bird, a snake, a frog, and a fish, é&c., 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 tke 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

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
‘Naturliche Schépfungsgeschichte,’
1868. Prof. Hualey, 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 dis-
cussed by Hackel, although he differs
on some points. He expresses,
also, his high estimate of the
general tenor and spirit of the
whole work.

2 Palxontology,’ 1860, p 199.

Crap. VI. Affinities and Genealogy.

159

Prof. Owen,” 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 disputea 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 Hackel 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, &c.; 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
Molluscoida 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 larve some-
what resemble tadpoles in shape,“ and have the power of
swimming freely about. M. Kovalevsky ™ has lately observed that
the larve of Ascidians are related to the Vertebrata, in their

nanner of development, in the relative position of the nervous
system, and in possessing a structure closely like the chordu
dorsulis of vertebrate animals; and in this he has been since

23 At the Falkland Islands I had under a simple microscope, plainly

the satisfaction of seeing, in April
1833, and therefore some years be-
fore any other naturalist, the loco-
motive larva of a compound Asci-
diao, closely allied to Synoicum,
but apparently generically distinct
trom it, The tail was about five
times as long as the oblong head,
and terminated in a very fine fila-
ment. It was, as sketched bv me

divided by transverse opaque parti-
tions, which I presume represent
the great cells figured by Kovalev-
sky. At an early stage of develope
ment the tail was closely coiled
round the head of the larva.

24 ¢ Mémoires de l'Acad. deg
Sciences de St. Pytersbourg,’ tom, x
No. 15, 1866,

160 The Descent of Man. Panr J,

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.” We should then be justified in believing
that at an extremely remote period a group of animals existed,
resembling in many respects the larve 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 pro-
vided 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 Quadru-
mana. 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

25 But I am bound to add that “ peut produire la disposition fonda-

some competent judges dispute this
conclusion; for instance, M. Giard,
in a series of papers in the ‘ Archives
de Zoologie Expérimentale,’ for 1872.
Nevertheless, this naturalist re-
marks, p. 281, “ L’o.ganisation de la
“larve ascidienne en dehors de
« toute hypothése et de toute théorie,
“yous montre comment la nature

“mentale du type vertébré (l’ex-
“istence d’une corde dorsale) chez
“un invertébré par la seule con-
“dition vitale de adaptation,
“et cette simple possibilité du
“passage supprime l’abime entre
“les deux sous-régnes, encore bien
“qu’en ignore par ot le passage
“ s'est fait en réalité ”

Luar. VI. Affinities and Genealogy. 161

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 mem-
brane. At astill 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 show
where the branchie once existed. In the lunar or weekly re-
current 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 mau, 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 afnller notice. It has long
beén known that in the vertebrate kingdom one sex bears
rudiments of various accessory parts, appertaining to the re-
productive 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.” But here we
encounter a singular difficulty. In the mammalian class the
males possess rudiments of a uterus with the adjacent passage,
in their vesicule prostatice; they bear also rudiments of
mamme, and some male Marsupials have traces of a marsupial
sack.27 Other analogous facts could be added. Are we, then, to
suppose that some extremely ancient mammal continued andro-
gynous, 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.”

26 Tnis is the conclusion of Prof.
Gegenbaur, one of the highest au-
thorities in comparative anatomy ;
sec ‘ Grundziige 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
aegine of even “the higher verte-

12

That various accessory parts,

“ brata are, in their early condition,
“hermaphrodite.” Similar views
have long been held by some authors,
though until recently without a
firm basis.

27 The male Thylacinus offers the
best instance. Owen, ‘ Anatomy of
Vertebrates,’ vol. iii. p. 771.

28 Hermaphroditism has been ob-
served in several speries of Serranus,
as well as in some other fishes

[62
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 cf
sexual selection, we shall meet with innumerable instances et
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 K6lliker 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 indi-
vidual 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.” 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
mamme? 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.

The Descent of Mftan.

Part lL

where it is either normal and sym-
metrical, or abnormal and uni-
lateral. Dy. Zouteveen has given
me references on this subject, more
especially to a paper by Prof. Hal-
bertsma, in the ‘Transact. of the
Dutch Acad. of Sciences,’ vol, xvi.
Dr. Giinther 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 veri-
ied the observations made by
Cavolini on Serranus, Prof. Erco-
{ani bas recent!y shewu (° Accad.

delle Scienze,’ Bologna, Dec. 28,
1871) that eels are androgynous.

29 Prof. Gegenbaur has shewn
(‘Jenaische 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 Monotre-
mata, See, also, a memoir by Dy.
Max Huss, on the mammary giands
-bid. B. viii. p. 176.

Cuap, VI.

163

Affinities and Genealogy.

It may be suggested, as another view, that long after the
progenitors of the whole mammalian class had ceased to be
audrogynous, 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 ;—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 the 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 mercly not
fully developed, and not functionally active. They are sympa-
thetically 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 mamme. 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,*' and that
afterwards from some cause (as from the production of a smaller
number of young) the maks ceased to give this aid, disuse of the
organs during maturity would lead to their becoming inactive ;
and from two well-known pr-nciples 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

3@ Mr. Lockwood believes (as by Prof. Wyman, in ‘ Proc. Boston

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

Soc. of Nat. Hist.’ Sept. 15, 1857;
also Prof. Turner, in ‘Journal of
£nat. and Phys.’ Nov. 1, 1866, p.
78. Dr. Giinther has likewise de-
scribed similar cases.

31 Madlle. C. Royer has suggested
a similar view in her ‘Origine de
Homme,’ &., 1870.

164

The Descent of Man.

Parr [.

organs would be lefi unaffected, so that they would be almost
aqually 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 te
add. Now as organisms have become slowly adapted to diver-
sified 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. Thesame 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 organisa-
tion 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 dis-
appear as soon as they have given birth to other and more
perfect groups. The latter, though victorious over their pre-
decessors, 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 fa'l into the errcr 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,** resembling the larvee of
existing Ascidians. These animals probably gave rise to a

32 The inhabitants of the sea- ditions for many generations, can

shore 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 1 complete cycle of
tidal changes in a fortnight. Con-
sequently, their food supply will
undergo marked changes week by
week. The vital functions of suca
animals, living under these con-

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 nor-
mal and abnormal processes have
one or more whole weeks as their
periods; this would be rendered
intelligible if the Vertebrata are de-
scended from an animal allied te

Cua. VI. Affinities and Genealogy. 165

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 birda
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 Lemuride ; and the interval is not very wide from
these to the Simiade. The Simiade 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 along line of progenitors. If any single link
in this chain had never existed, man vould 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 fect;
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.

the existing tidal Ascidians. Many cess or function, would not, when

instances of such periodic processes
might be given, as the gestation of
mammals, the duration of fevers, &c.
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
‘owl in three; those of the duck in
‘our; 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 pro-

once gained, be liable to change;
consequently it might be thus trans-
mitted 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 gesta-
tion in each mammal, and the
hatching of each bird’s eggs, and
many other vital processes, thus
betray to us the primordial birth
place of these animals.

166 The Descent of Man. Paar J.

CHAPTER VII.
ON THE RacEs oF Man.

The nature and valie of specific characters—Application to the races o
tan—Arguments in favour of, and opposed to, ranking the so-called
races of man as distinct species—Sub-species—Monogenists and poly-
genists—Convergence of character—Numerous points of resemblance in
body and mind between the most distinct races of man—tThe state of
man when he first spread over the earth—Each race not descended from
a single pair—The extinction of races—The formation ot races—The
effects of crossing—Slight influence of the direct action of the con-
ditions of lite—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 ahout to enquire what is the value of the dif-
ferences 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 varicties. Geographical distribution is ofte1
brought into play unconsciously and sometimes consciously ; 50
that forms living in two widely separated areas, in which moat

Ouar, VII. The Races of Man. 167

of the other inhabitants are specifically distinct, are themselves
usually looked at as distinct ; but in truth this affords no aid in dis-
tinguishing geographical races from so-called good or true species.

Now let us apply these generally-admitted pringiples 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 ;) 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 sup-
posed; 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
Muséum 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. Neverthe-
less, 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,? the capacity of the lungs, the form and capacity of
the skull, and even in the convolutions of the brain. 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

1 «History of India,’ 1841, vol. i.

‘On the capacity of the lungs,’ p. 471.
p- 323. Father Ripa makes exactly

See also the numerous and valuable

the same remark with respect to
she Chinese.

2 A vast number of measure-
ments of Whites, Blacks, and In-
lians, are given in the ‘Investiga-
tions in the Military and Anthropo-
log. Statistics of American Soldiers,’
by B. A. Gould, 1869, pp. 298-358 ;

tables, by Dr. Weisbach, from the
observations of Dr. Scherzer and
Dr. Schwarz, in the ‘Reise der
Novara: Anthropolog. Theil,’ 1867.

3 See, for instance, Mr. Marshall’s
account of the brain of a Bush-
woman, in ‘ Phil. Transact.’ 1864,
p. 519,

168 The Descent of Man. Part IL

struck with the contrast between the taciturn, even morose,
aborigines of § America and the light-hearted, talkative negroes,
There is a nearly similar contrast between the Malays and tha
Papuans,* 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. Ifa naturalist, who had
uever 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 dis-
position. 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 He would also hear,
on the authority of an excellent observer, Dr. Lund,® that the
human skulls found in the caves of Brazil, entombed with many
extinct mammals, belonged to the same type as that now pre-
vailing throughout the American Continent.

4 Wallace, ‘The Malay Archi-
pelago,’ vol. ii. 1869, p. 178.

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 repre-
sentations 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 de-
gree 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 IJ., or the Great, has
features superbly European ; where-
us Kocs, another firm believer in
she specific distinctness of the races ¢f

man (‘Races of Man,’ 1850, p. 201),
speaking of young Memnon (the
same as Rameses II., as I am in-
formed by Mr. Birch), insists in the
strongest manner that he is identical
in character with the Jews of Ant-
werp. Again, when I looked at the
statue of Amunoph III.,] 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) de-
scribe him as a hybrid, bus not of
“ negro intermixture.”

® As quoted by Nott and Gliddon,
‘Types of Mankind,’ 1854, p. 459.
They give also corroborative evi-
dence; but C. Vogt thinks that the
subject requires further investiga:
tion.

Ouar. VIL. The Races of Man. 169

Our naturalist would then perhaps turn to geographical dis-
tribution, 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 alow
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,’
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 zovlogical 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 spe-
cifically 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

’ (Diversity of Origin of the Human Races,’ in the ‘Christian
Examiner,’ July 1850,

170 The Descent of Man.

Parr f,

countries from the different races of man ;* and he finds that
they differ, nut only in colour, but in the structure of their
elaws 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
Kaftirs; 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 inhahiting 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®
of Professor Broca, a cautious and philosophical observer, and in
this he would find good evidence that some races were quite
tertile 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.” Again, it has often been
said that when mulattoes intermarry they produce few children;
on the other hand, Dr. Bachman of Charleston" positively

8 ‘Transact. R. Soc. of Edinburgh,’
vol. xxii. 1861, p. 567.
® ‘On the Phenomena of Hybridity

who have borne children to a white
man are afterwards sterile with
their own race, is disproved. M. A.

in the Genus Homo,’ Eng. translat.
1864.

10 See the interesting letter by
My. T. A. Murray, in the ‘ Anthro-
polog. Review,’ April 1868, p. liii.
In this letter Count Strzelecki’s
atatewent, thal Australian women

de Quatrefages has also collected
(Revue des Cours Scientifiques,’
March 1869, p. 239) much evidence
that Australians and Luropeans are
not sterile when crossed,

No ¢An Examination of Pref
Agassiz’s Sketch of the Nit. Pro

Unar. VIL, The Races of Man.

171

asserts that ho has known’ mulatto families which have inter-
married 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.” In the United States the
census for the year 1854 included, according to Dr. Bachman,
405,751 mulattoes ; and this number, considering all the cireum-
stances 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 interior
vitality of mulattoes is spoken of in a trustworthy work™ as a
well-known phenomenon; and this, although a different considera-
tion 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 con-
nection there is in hybrids between lessened fertility and vitality ;
other analogous cases could be cited.

Even if it should hereafter be proved that ali 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 Jife, 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

vinces of the Animal World,’ Charles-
ton, 1855, p. 44.

12 Dr, Rohlts writes to me that
he found the mixed races in the
Great Sahara, derived from Arabs,
Berbers, and Negroes of three tribes,
extraordinarily fertile. Qn the other
hand, Mr. Winwood Reade informs
me that the Negroes on the Gold
Soast, 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 fuur hundred years, s¢
that the natives have had ample
time to gain knowledge through
experience.

13 ¢ Military and Anthropolog.
Statistics of American Soldiers,’ by
B. A. Gould, 1869, p. 319.

172 The Descent of Man. Part 1

fertile. The degrees of sterility do not coincide strictly with
the degrees of difference between the parents in external structure
or habits of tife. 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,* 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 off-
spring 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 con-
clusion that no general rules of this kind can be trusted. The
ordinary result of a cross is the production of a blended or

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 in-
capacity of certain trees to be graft-
ed together, is incidental on other
acquired differences. ‘The nature
of these differences is unknown, but
they relate more especially to the re-
productive 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 habi-
tuated to fixed conditions; for we
know that changed conditions have
a special influence on the repro-
ductive system, and we have good
reason to believe (as before re-
marked) that the fluctuating con-
ditions of domestication tend to
eliminate that sterility which is so
general with species, in a natural
state, when crossed. It has else-
where 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 ac-
quined through natural selection:
we can see that when two forms
aive already heen rendeied very

sterile, it is scarcely possible that
their sterility should be augmented
by the preservation or survival of
the more and more sterile indi-
viduals; for as the sterility in-
creases, fewer and fewer offspring
will be produced from which to
breed, and at last only single in-
dividuals 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 tormed from species which
when crossed yield fewer and fewer
seeds, to species which never pro-

duce a single seed, but yet are

affected by the poilen of the othe:
species, as shewn by the swelling
of the germen. It is here mani-
festly impossible to select the more
sterile individuals, which have al-
ready 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 ditfer-
ences in the constitution of the re-
productive system of the speciea
which are crossed

Cuap. VIL The Races of Man. 173

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.» 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
ditferences 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
undoubtully 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 popu-
lation consisting of Indians and Spaniards blended in various
degrees.* 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

18 ‘The Variation of Animals,’ success and energy of the Paulistas
&e., vol. ii. p. 92. in Brazil, who are a much crossed

16M. de Quatrefages has given race of Portuguese and Indians, with
(‘ Anthropolog. Review,’ Jan. 1869, a mixture of the blood of other
p. 22) an interesting account of the races.

(74 The Descent of Man Part 1

crossed in all degrees. Many analogous cases could be be added ;
for instance, in Africa. Hence the races of man are not suf-
ficiently 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
tughly 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 varics
much in some races; 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.’* 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

17 For instance with the abori-

18 See a good discussion on this
gines of America and Australia.

subject in Waitz, ‘Introduct. to

Prot. Huxley says (¢ Transact. Inter-
nat. 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,” &c.

Anthropology,’ Eng. translat, 1864,
pp. 198-208, 227. I have taken
some of the above statements from
H. Tnttle’s ‘Origin and Antiquity
of Physical Man,’ Boston, 1866, p
35.

Onar. VIL The Races of Man. 17§

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 en-
countered cases (I speak after experience) precisely like that of
man’ and if of a cautious disposition, he will end by uniting alli
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 chjects 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. Neverthcless, it must be
confessed that there are forms, at least in the vegetable king-
dom," 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 diffi-
culties 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

19 Prof, Nageli has carefully de- has made analogous remarks ov
scribed several striking cases in his some intermediate forms in the
‘ Hotan’sche Mittheilungen,’ B. ii. Composite of N. America
1866, 1, 294-369. Prot. Asa Gray

176 The Descent of Man. Parr 1

can generally be arranged in little groups round other species,
like satellites round planets.”

The question whether nawukind consists of one or several
species has of late years beeu 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 as 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. Butitis 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 he
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 ex-
pressing their amount of difference." With our domestie
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 specics
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

* ‘Qrigin of Species, 5th edit. in the ‘Fortnightly Review,’ 1865
p. 68, p. 275.

21 See Prof. Huxlcy to this effect.

Cuap. VII. The Races of Man. 177

from a common stock, the differences between the races aud
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 tha
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,” they converged in character. When man selects the off-
spring 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,”* 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 toa
fish, may indeed be said to be cases of convergence; but this
term has never been applicd to superficial and adaptive resem-
blances. 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 mole-
cular 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 physicial condi-

7 ‘Lectures on Man,’ Eng. trans- schichte, &c., Schwerneschadel,’
lat. 1864, p. 448. 1864, s.104. With respect to cattle,

23 ¢Die Racen des Schweines,’ see M. de Quatrefages, ‘Unité de
1860, ». 46. ‘Vorstudien fir Ge- 1]’Espéce Humaine,’ 1861, p. 119.

13

178 The Descent of Man. Part |

tions, and still more on the surrounding organisms which com-
pete with each,—and lastly, on inheritance (in itself a fluctuating
clement) from innumerable progenitors, all of which have had
their forms determined through equally complex relations. Ii
appears incredible that the modified descendants of two organ-
isms, 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, evi-
dence of their descent from two primitive stocks is, according to
Von Nathusius, still plainly retained, in certain bones of their
skulls. Ifthe 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, &e., 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 inde-
pendently 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 bourd 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™ 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

*% Tylor’s ‘Early History of Man- 1anguage, see p. 54. Lubbock's
kind, 1835: withiespect to gesture- ‘Prehistoric ‘Times,’ 2nd edit. 1869,

Onep, VIL The Races of Man. 179

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,” 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 archeologists **
with respect to certain widely-prevalent ornaments, such as zig-
zags, &c.; and with respect to various simple beliefs and cus-
toms, such as the burying of the dead under megalithic struc-
tures. I remember observing in South America,”’ 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 struc-
ture 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, pre-
ceded 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 birth-place ;
for if once learnt they would never have been forgotten.* He

25 ¢Qn Analogous Forms of Im- ‘Journal of Ethnological Soc.’ as
plements,’ in ‘Memoirs of Anthropo- given in ‘Scientific Opinion,’ June
log. Soc.,’ by H. M. Westropp. ‘The 2nd, 1869, p. 3.

Primitive inhabitants of Scandi- 27 ¢ Journal of Researches: Voyage
navia,’ Eng. translat. edited by Sir of the “ Beagle,”’ p. 46.
J. Lubbock, 1868, p. 104. 28 ¢Prehistoric Times,’ 1869, p

2 Westropp, ‘On Cromlechs,’ &c., 574.

180 The Descent of Man. Pant 1.

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-
mhabitants 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 socia) 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
suspect d 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 move highly-developed tongues. With-
out 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 when
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 poly-
genists will die a silent and unobserved death.

One other question ought not to be passed over without notice,
namely, whether, as is scmetimes assumed, each sub-species or
race of man hag sprung from a single pair of progenitors. With

cmap. VIL The Extinction of Races. 181

sur domestic animals a new race can readily be formed by care-
fully matching the varying offspring from a single pair, or even
trom 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 in-
dividuals 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
kuown. 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 Schaaffhausen,”
“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 .ow
or simious, and of high characteristics. This race is “ entirely

® Translation in ¢ Anthzopological Review,’ Oct. 1868, p. 431

i§2 The Descent of Man. Part L

" differer.t from any other, ancient or modern, that we have ever
“heard of.” {t differed, therefore, from the quaternary race of
the caverns of Belgium.

Man can long resist conditions which appear extremely un-
favourable for his existence 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 with-
out 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 trike 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, licen-
tiousness, 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.”

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, cr 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; and so it
may be with the evil effects from spirituous liquors, as well as
with the unconquerably strong taste for them shewn by somany

“ ‘Transact. Internat. Congress terben der Naturvélker,’ 1868, s. 82.

ot Prehistoric Arch,’ 1868, pp. 172- 32 Gerland (ibid. s. 12) gives facta
175. See also Broca (translation) in support of this statement.

ia ‘Anthropological Review,’ Oct. 33 See remarks to this effect ip
1868, p. 410. Sir H. Holland’s ‘ Medical Notes and

*' Dr. Gerland ‘Caper das Auss- Reflections,’ 1839, p. 390.

Sua. VIL The Extinction of Races. 183

savages. It further appears, mysterious as is the fact, that
the first meeting of distinct and separated people generates
disease** 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.”

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
sivilised 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.** The most po-
tent 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,”
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 inall of 111 souls. In 1835 only one hundred were left.

3 [| have collected (‘Journal of Savage Life,’ 1868, p. 284.

Researches, Voyage of the “ Beagle,”’ 36 Bagehot, ‘ Physics and Poli-

p. 435) a good many cases bearing
en this subject: see also Gerland,
bid. s. 8. Poeppig speaks of the
“breath of civilisation as poisonous
“to savages.”

45 Sproat, ‘Scenes and Studies ot

ties,’ ‘Fortnightly Review,’ April
1, 1868, p. 455.

37 All the statements here given
are taken from ‘The last of tre
Tasmanians,’ by J. Bonwick, 1870.

184 The Descent of Man. Part L

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 tenchildren.* 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 tu 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
’ “eyeat 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.

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.‘°
The decrease in number since 1830 is admitted by every one,
including the natives themselves, and is still steadily progress-
ing. 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

38 This is the statement of the 1870, p. 90; and the ‘Last of the
Gcrernor of Tasmania, Sir W. Deni- Tasmanians,’ 1870, p. 386.
son, ‘ Varieties of Vice-Rega: Life,’ 40 “Observations on the Aboriginal
1870, vol. 1. p. 67. Inhabitants of New Zealand,’ pub
3° For tnese cases, see Bonwick’s lished by the Government, 1859.
‘Daly Life of the Tasmanians,’

“nap, VIL, The Extinction of Races 185

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 58,700, 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.!“ My. Fenton, after shewing in detail the in-
sufficiency of the various causes, usually assigned in explana-
tion of this extraordinary decrease, such as new diseases, the
profligacy of the women, drunkenness, wars, &c., 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.
lir. Fenton contrasts with astonishment the decrease in New
Zealand with the increase in Ireland; countries not very dis-
similar 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
pe seen, when we consider the influence of changed conditions
on fertility, that they are probably right. The diminution began
vetween 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,? that the Melanesians of the New Hebrides and
reighbouring archipelagoes, suffered to an extraordinary degree
in health, and perished in large numbers, when they were

‘| ¢New Zealand,’ by Alex. Ken- C. M. Younge, 1874; see more
nedy, 1873, p. 47. especially vol. i. p, 530,
#2 <¢Life of J. C. Patteson,’ by

186 The Descent of Man. Parr I,

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 Islznus
is as notorious as that of New Zealand. It has been rougily
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 :

Annual rate of decrease
NaTIVE PoPULATION, per cent., assuming it

— to have been uniform be-
(xcept during 1832] tween the successive cen-
and 1836, when the | suses; these censuses be-
few foreigners in the | ing taken at irregular
islands wereincluded). | intervals.

YEAR,

1832 130,313.

} 4°46
1836 108,579

\ 2°47
1853 71,019

} 0-81
1860 67,084

} 2°18
1866 58,765,

j 217

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
|| eent.! 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 eigkty married women, only thirty-
nine had ever borne children; and “ the official report gives an
“average of haif a child to each married couple in the whole

Cnar, VII, The Extinction of Races. 187

“island.” This is almost exactly the same average as with the
Tasmanians at Oyster Cove. Jarves, who published his History
in 18438, says that “ families who have three children are freed from
“all taxes; those having more, are rewarded by gitts 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 1889, 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 weak-
ness of constitution in the children, in relation to the lessened
fertility of their parents. There is, moreover, a further resem-
blance 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 125-46
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, by 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 Englishman 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.*®

“8 The foregoing statements are Islands,’ 1851, p. 277. Ruschen-
taken chiefly from the following berger is quoted by Bonwick, ‘Last
works: ‘Jarves’ History of the of the Tasmanians,’ 1870, p. 378.
Hawaiian Islands,’ 1843, p. 400-407. Bishop is quoted by Sir E. Belcher,
Cheever, ‘Life in the Sandwich ‘Voyage Round the World,’ 1843,

188 The Descent of Man. Parr I.

Lastly, Mr. Macnamara states*! 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 inhabit-
ants 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, aud 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 sus-
ceptible 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,
cormbined 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 cascs 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 abovu
cases. Some writers have suggested that the aborigines of
islands have suffered in fertility and health from long continued

vol. i, p. 272. IT owe the census of of the above-named works. I have
the several years to the kindness of omitted the census for 1850, as !
Mr. Coan, at the request of Dr. You- have seen two widely different num-
mans of New York; and in most bers given.

eases I have compared the Youmans 44 ¢The Indian Medical Gazette,
figures with those given in several Nov. 1, 1871, p. 240.

Cuap, VIL The Extinction of Races. 189

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.*°

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
ot 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 in-
stance, 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.* 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
spevies in a group is rendered sterile, whilst the others are not
so; on the other hand, a single species may retain its fertility

45 On the close relationship of the Scotland, Dr. Mitchell, ‘Edinburgh
Norfolk Islanders, see Sir W. Deni- Medical Journal,’ March to June.
son, ‘Varieties of Vice-Regal Life,’ 1865.
vol. i. 1870, p. 410, For the Todas, 46 For the evidence on this head,
wee Col. Marshall’s work, 1873, p. see ‘Variation of Animzls’ &c.,
110. For tle Western Islands of vol. ii. p. 111.

igo The Descent of Man. Part 1.

whilst most cf 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 ina 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
reprodactive 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 inha-
bited 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.?7 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 in-
ercased so rapidly, that although sixteen of them returned to Pit
cairn Island ia 1859, they numbered in January 1868, 300 souls

st ¢Variat on of Animals,’ &c., vol. ii., p 16.

Cuap. VIL The Extinction of Races. 191

the malcs and females being in exactly equal numbers, What a
contrast does this case preseut with that of the Tasmanians;
the Norfolk Islanders tncreased in only twelve and a half years
from 194 to 800; whereas the Tasmanians decreused during
fifteen years from 120 to 46, of which latter number only ten
were children.”®

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, in-
creased 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
us 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 extinc-
tion of one of the higher animals—of the fossil horse, for in-
stance, which disappeared from South America, soon afterwards
to be replaced, within the same districts, by countless troops
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

48 These details are taken from May 29th, 1863. The followug
The Mutineers of the “Bounty,”’ statements about the Sandwich Is-
oy Lady Belcher, 1870; and trom landers are from the ‘Honclulu
Pitcairn Island, ordered to be Gazette,’ and from Mr, Coan.
printed by the House of Commons,

The Descent of Man. Part L

192

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 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,*
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 hetcrogeneous
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.” Whether a heterogeneous people, such as the inhabi-
tants 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 sclection™ 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 expusure to different climates; but
Pallas first shewed that this is not tenable, and he has since been
followed by almost all anthropologists.5? This view has been
rejected chiefly because the distribution of the variously
coloured races, most of whom must have long inhabited their

-49 ¢On Anthropology,’ trausla-
tion ‘Anthropolog. Review,’ Jan.
1868, p. 38.

50 <The Annals cf Rural Bengal,’
1888, p. 134.

51 ©The Varia‘‘on of Animals and
Pliots under Dowmesticatiun, vol. ii.
p. 35.

52 Pallas, ‘Act. Acad. St. Peters-
burg,’ 1780, part ii. p. 69. He was
followed by Rudolphi, in his ‘ Bey-
trage zur Anthropologie,’ 1812.
An excellent summary of the evi-
dence is given by Godron, ‘ De
V’Espce,’ 1859, vol. ii. p. 246, &e

Cuar, VIL, The Formation of Races.

193

present homes, does not coincide with corresponding ditferences
of climate. Some little weight may be given to such cases as
that of the Dutch families, who, as we hear on excellent autho-
rity,“ 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 appear-
ance in various parts of the world of gipsies and Jews, though
the uniformity of the latter has been somewhat exaggerated.™
A very damp or a very dry atmosphere has becn 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.

Various facts, which I have given elsewhere, prove that the
colour of the skin and hair is sometimes correlated in a surpris-
ing 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. It has long been known that negroes, and even
mulattoes, are almost completely exempt from the yellow-fever,

“ so destructive in tropical America.*’ 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.*® This immunity in the negro seems to
be partly inherent, depending on some unknown peculiarity of
constitution, and partly the result of acclimatisation. Pouchet**

53 Sir Andrew Smith, as quoted
by Knox, ‘Races of Man’ 1850, p.
473.

54 See De Quatrefages on this
head, ‘Revue des Cours Scienti-
fiques,’ Oct. 17, 1868, p. 731.

55 Livingstone’s ‘Travels and Re-
searches in S. Africa,’ 1857, pp.
338, 329. D’Orbigny, as quoted by
Golron, ‘De l'Espéce,’ vol. ii. p.
266,

56 See a paper read before the
Royal Soc. in 1813, and published
= nis Essays in 1818. I have given
tn account of Dr. Wells’ views in

14

the Historical Sketch (p. xvi.) to my
‘Origin of Species.’ Various cases
of colour correlated with constitu-
tional peculiarities are given in my
‘Variation of Animals under Do-
mestication,’ vol. ii, pp. 227, 335.

57 See, for instance, Nott and
Gliddon, ‘Types of Mankind,’ p. 68,

88 Major Tulloch, in a paper read
before the Statistical Society, April
20th, 1840, and given in the ‘ Athe-
neum,” 1840, p. 353.

59 «The Plurality of the Humar
Race’ (translat.), 1864, p. (0.

The Descent of Man. Part l,

194

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 origin-
ally 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 some-
what liable to tropical fevers, after having resided for some time
in a colder climate.” 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 inhabit-
ants 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,” to ascertain how far it holds good. The late Dr.

6 Quatrefages, ‘ Unité de 1’Espace
Humaine, 1861, p. 205. Waitz,
‘Introduct. to Anthropology,’ trans-
lat. vol. i. 1863, p. 124, Living-
stone gives analogous cases in his
‘Travels.’

In the spring of 1862 I ob-
tained 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 re-
marks, but I have received no re-
turns. “As several well-marked
“vases have been recorded with
* our domestic animals of a relation
“ hetween the coiour of the dermal
“ appendages aid the consti‘ution ;
“and it beiag nutorivus that there

“is some limited degree of relation
“ between the colour of the races of
“man and the climate inhabited by
“them; the following investiga-
“tion seems worth consideratica.
“ Namely, whether there is any re-
“lation 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,
“asa 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 sume medical gentle

Onay. VII. The Formation of Races.

195

Daniell, who had long Jived 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 buy 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 he does not think 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. 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,® 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. Ihave 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,

‘men, 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 consti-
“tutional liability to tropical dis-
“eases, Perhaps no such relation
“ would be discovered, but the in-
“ vestigation is well worth making.
“Jn case any positive result were
“obtained, it might be of some
“ practical use in selecting men for
“any particular service. Theoreti-
“ cally the result would be of high
“interest, as indicating one means
“ by which a race of men inhabiting
“from a remote period an un-
“healthy tropical climate, might
“have become dark-coloured by
“the better preservation of dark-
“haired or dark-complexioned in-
* dividuals during 2 long succession

“ of generations.”

8 ¢ Anthropological Review,’ Jan.
1866, p. xxi. Dr. Sharpe also says,
with respect to India (‘ Man a Spe-
cial Creation,’ 1873, p. 118), that
“it has been noticed by some medi-
“cal 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 ap-
“ pear to be good grounds for this
“yvemark.” On the other hanc,
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.

63 ¢ Man a Special Creation,’ 1873,
p 119.

The Descent of Man. Parr ),

196

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.“* Whether the
saving of the skin from being thus burnt is of sufficient impor-
tance to account for a dark tint having been gradually acquired
by man through natural selection, 1am 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 shortcr 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.™

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
adwitted, the European settlers in the United States undergo a
slight but extraordinarily rapid change of appearance. Their
hodies 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 con-
siderable body of evidence shewing that in the Southern States
the housc-slaves of the third generation present a markedly
different appearance from the field-slaves.®

“© Variation of Animals and settled in Georgia, have acquired 1n

Plants under Domestication,’ vol. ii.
pp. 336, 337.

8° See, for instance, Quatrefages
(‘ Revue des Cours Scientificues,’
Oct. 10, 1868, p. 724) on the effects
of residence in Abyssinia and Arabia,
and other analogous cases. Dr.
Rolle (‘Der Mensch, seine Abstam-
mung,’ &c., 1865, s. 99) states, on
the authority of Khanikof, that the
greater number of German families

the course of two generations dark
hair and eyes. Mr. D. Fortee in-
forms me that the Quichuas im the
Andes vary greatly in colour, ac
cording to the position of the valleys
inhabited by them. ‘3

86° Harlan, ‘Medical Researches,
p. 532. Quatrefages (‘Unité de
I'Espéce Humaine, 1861, p. 128)
has collected much evidence on this
head.

Cnap, VII. The Formation of Races. 197

If, however, we look to the races of man as distributed over
the world, we must infer that their characteristic differences can-
not 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 Fnegians live on the marine produc-
tions of their inhospitable shores; the Botecudos 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 habitu-
ally live in canoes, may have their legs somewhat stunted ;
those who inhabit lofty regions may have their chests enlarged ;
und 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 Icssened 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.” Increased bodily stature, without any corresponding
increase in the size of the brain, may (judging from the pre-
viously adduced case of rabbits), have given to some races an
elongated skull of the dolichocephalic type.

Lastly, the little-understood principle of correlated develop-
ment 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.“ The colour also of the skin, and the odour

8 See Prof. Schaaffhausen. trans- 68 Mr. Catlin states (‘N. Ameri-
lat. in ‘Anthropologieal Review,’ can Indians,’ 3rd edit, 1842, vol. I.
Oct. 1868, p. 429. p. 49) tat in the whule wite af

198 The Descext of Man.

Part I.

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 the excretory pores are related. If we may judge
from the analogy of our domesticated animals, many modifica-
tions 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 satisfac-
tory 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 inquire
whether slight individual differences, to which man is emi-
nently liable, may not havé- 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 varia-
tions 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. J 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 indivi-
duals 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

the Mapdans, 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,
whilat the hair of other coloure is

fine and soft.

® On the odour of the skin,
Godron, ‘Sur )’Espéce,’ tom. ii. p.
217. On the pores in the skin,
Dr. Wilckens, ‘Die Aufgaben der
Landwiuth, Zootechnik,’ 1869, s. 7,

Onap. VII. Structure of the Brain. 199

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 the 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, &c., are of a kind which might have been
expected to come under the influence of sexual selection. Butin
order to treat this subjeet 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.

NovTe ON THE ResEMBLANCES AND DIFFERENCES IN THE STRUCTURE
AND THE DEVELOPMENT OF THE Brain IN Man anv ApEs, By
Proresson Huxrey, F.R.S.

The controversy respecting the nature and the extent of the differ-
ences in the structure of the brain in man und the apes, which arose
some fifteen years ago, has not yet come to an end, though the subject
niatter of the dispute is, at present, totally different from what it was
formerly. Ib was originally asserted and re-asserted, with singular
pertinacity, that the brain of all the apes, even the highest, differs trom
that of man, in the absence of such conspicuous structures as the
pesterior lobes of the cerebral hvmispheres, with the posterior cornu of
ihe 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 deve-
loped in apes’ as in human brains, or even butter; and that it is character-
istic 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” 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

7 ¢Die Grosshirn-Windungen des Menschen; ‘Abhandlungen der K
Bayerischen Akademie.’ Bd, x., 1868,

200 The Descent of Man. Paar L.

differences between apes and men in this respect, Iam glad to make a
citation from him.

“That the apes, and especially the orang, chimpanzee and gorilla,
“ come very close t» 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 Linnus, that man should be
* placed, merely as a peculiar spevies, at the hvad of the mammalia and of
“ those apes. Buth shew, in all their organs, so close an affinity, that the
“ most exact anatomical investigation is needed in order to demonstrate
“ those differences which reilly 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, cume very close to one
“another ’ (1. c. p. 101).

There remains, then, no dispute as to the resemblance in fundamental
characters, between the ap-sbrainand man’s; nor any as to the won-
derfully close similarity between the chimpanzee, orang and man, in
even the details of the arrangement of the gyri and sulci of the cerebral
kemispheres. 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 anc extent of these differences. It isadmitted that the man’s
ecrebril hemispherce 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 yyri and sulei
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
go strongly marked a fcature of the ape’s brain is but faintly marked.
But it is also clear, that none of these ditterences 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 :7!

“ 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 in another specimen,
‘also the right hemisphere, it proceeded for four-tenths of an inch out-
“ wards, and then extended downwards, as far as the lower margin of the
“ ou'er surface of the hemisphere. The imperfect definition of this fissure
“‘in the majority of human brains, as compared with its remarkable dis-
“ tinctness in the brain of most Quadrumana, is owing to the presence, in
“ the former, of certain superficial, well marked, secondary convolutiong
“ 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 ” (1. ¢. 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 oblitera-
tion of the external perpendicular sulcus by “ bridging convolutions,” on
one side or the other, has been noted over and over again by Prof

¢Convolutions of the Human Cerebrum Topographically Considered,
1868, p. 12.

Cuer, VIT. Structure of the Brain. 201

Rolleston, Mr. Marshall, M. Broca and Professor Turner. At the
couclusion of a special paper on this subject the latter writes :7

“The three specimens of the brain of a chimpanzee just described,
“ prove, that the generalisation which Gratiolet has attempted tu draw of
**the complete absence of the first connecting convolution and the
‘* voncealment of the second, as essentially characteristic features in the
* rain of this animal. is by nu means universally applicable. In only one
“specimen did the brain, in these particulars, follow the law which
“ Grativlet has expressed. As regards the piesence of the superior bridg-
“ ine convolution, [ am inclined to think thit it has existed in one he mi-
* sphere, ut least, ina majority of the bruins of this unimal which have, up
* to this time, bcen tigured ordescribed. The superficial positiun of the
“ second bridging convolution is evidently less frequent, and has as yet,
* T believe, only been seen in the bra:n ' A) recorded in this communi-
4 cation, The asymmetrical arrang-emcnt in the convolutions of the
* two hemispheres, which previvus observers hive referred to in their
“ descriptions is also well illustruted in these specimens.” (pp. 8, 9.)

Even were the presence of the temporo-occipital, or external per-
p.ndicular, sulcus a mark of distinction between the higher apes and
man, the value of such a distinctive character would be 1endcred very
doubtful by the structure of the brain in the Platyrhine»pes. In fact
while the temporo-occipital is one of the most constant of sulci in
the Catarhine, or Old World, apes, it is never very strongly developed
in the New World apes; it is absent in the smaller Platyrhin. ;
rudimentary in Pithecia ;"* and more or less obliterated by br.dzing
convolutions in Ateles,

A charactir 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 convolu-
tion 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 consider-
ably less complicated and more symmetrical than in the Europeau
brain, while, in some individuals of the chimpanzee, their complexity
and asymmetry become notable. This is paiticularly 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 une. circumstance in which the orang’s and chim-
panzee’s brains resemble man’s, but in which they differ from the lower
apes, and that is the presence of two corpura 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,"

“So far as cerebral structure goes, therefore, it is clear that man

7 Notes more especially on the 73 Flower. ‘On the Anatomy of
oridging convolutions in the Brain ithecia Monachus,’ * Proceedings of
cz the Chimpanzee, ‘Proceedings of the Zoological Society,’ 1862.
the “oyal Society of Edinburgh,’ 74 <Man’s Place in Nature,’ p. 162
186.

202 The Descent of Man. Part &

“ diff-rs less from the clhirapanzee or the orang, than these do even
“froia the monkeys, and that tue difference hetween the braiu of the
“chimpanzee and cf mun is almost insigniticant, when compared with
“that between the chimp:nzee brain and thot of a Lemur.”

In the paper to whuh I have referred, Professor Bischoff does not
deny tlie second part of this sttement, but he first makes the irrelevant
remark that it is not wonderful if the brains of an orang and a Lemur
ere very different; and secondly, goes on to assert that, «If we succes=
* sively compare the brain of aman with that of an orang; the brain of
“ this with that of a chimpanzee; of this with tha’ of a vorilla, and so
“on ota //ylobates, Semnoprthecus, Cynocephalus, Cercopithecus, Macacus.
“ Cebus, Callithria, Lemur, stenops, Hapale, we sha.) not meet with a
“ greater, or even as great a, break in the degree of development of the
“ eonvo.utions, as we tind between tue brain of a man and that of an
“orang or chimpanzee.”

To which IL reply, firstly, that whether this assertion be true
or false, it Las notbing wh-tever to do with the proposition enunciated
in ‘Man's Place in Natuie,’ whi-h refers not to the development of the
convoluti ms alone, but to the structure of the whole brain. Lf Professor
Bischoff had taken the trouble to refer to p. 96 of the work he criticises,
in fact, lie would huve found the fullowing passage: ‘‘ And it is a
“yemarkable circumstance that though, so far as our present know-
“ ledge extends, there is one true structural break in the series of forms
“of Simian brains, this hiatus dces 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 with has yet been examined, in fact,
“ has its cerebellum partially visible from above; and its posterior lobe,
“with the contained posterivr cornu and hippocampus minor, more or
“Jess rudimentary. Every marmozet, American monkey, Old World
“monkey, baboon, or maulike ape, on the contrary, has iis 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 mide; and it does not appcar to me to be more thin
apparently woakened by the subsequent discovery of the relutively
sinall development of the posterivr 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 pluce, as Professor
Bischoff most unaccountably does, we write the series of animals
he has chosen to mention as follows: Homo, Pithecus, Troylodytes,
Hylobates, Semnopithecus, Cynocephalus, Cercopithecus, Macacus, Cebus,
Callithriz, Hapale, Lemur, Steuops, I venture to reattirm that the
great break in this series lies tetween Hapale and Lemur, and that
tuis break is consideably greater than that between any other two
term: 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 mide the following
voservations in the course of his description of the brain of the Javan
Loris.’>

1 ‘Transactions of the Zoclogical Society,’ vol. . i862

Cnar, VIL Structure of the Brain 203

“ 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 commouly supposed
“to approach this family in other respects, viz., the lower members of
“the Piatyrhine group.”

So far as the structure of the adult brain is concerned, then, the very
eonsidvrable additions to our knowledge, which have been made by the
researches of so many investigators, duiing the past ten years, fully
justify the statement which [ made in 1563. But it has been suid
that, adinitting the similarity between tle adult brains of man and
upes, they are nevertheless, in reality, widely different, because thry
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 ditferences of development really exist. But I dcny
that they do exist. On the contrary, there is a fundamental agree-
ment in the development of the bruin in men and apes,

Gratiolet or ginated the statement that there is a fundamental
difference in the development of the brains of apes and that uf man—
consisting in this; that, in the »pes, the sulci which first make their
appearance are situated on the po-terior region of the cerebral heii-
spheres, while, iu the human foctus, tue sulci first become visible ou the
frontal lobes.”

This general statement is ba:ed 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
(i. ¢. p. 39), aud the other of a human foetus at the 22nd or 23rd week
of uterovestation, iu wiich Gratiolet notes that the insula was un-
covered, but that nevertheless ‘ des incisures sement Je lobe antirienr.
“ une scissure peu profonde indique ia sép..ration du lobe occipital, tres-

76 “Chez tous les singes, les plis Rolando, and one of the frontal

“ postérieurs se développent les pre-
“miers; les plis antérieurs se
“ développent plus tard, aussi la
“ vertébre occipitale et la pariétale
“sont-elles relativemeut trés-grandes
“ chez le fetus. L’Homme présente
“une exception remarquable quant
“4 ’époque de l’apparition des plis
“ frontaux, qui sont les premiers
“ indiqués ; mais le développement
“ général du lobe frontal, envisagé
“seulement par rapport 4 son
“ volume, suit les mémes lois que dans
“les singes:” Graticlet, ‘Mémoire
sur les plis cérébraux de l’Homme
et des Primates, p. 39, tab. iv.
fig. 3.

1 Gratiolet’s words are (1. c. p.
39): “Dans le foetus dont il s’agit
“ les plis cérébraux postérieurs sont
“bien développés, tandis que les
* plis du lobe frontal sont 4 peine
“indiqués.” The figure, however
(PI. iv. fig. 3), shews the fissure of

sulci, plainly enough. Nevertheless,
M. Alix, in his ‘Notice sur les
travaux anthropologiques de Gratio-
let? (Mém. de la Société d’Anthro-
pologie de Paris,’ 1868, p. 82),
writes thus: “ Gratiolet a eu entre
“ les mains le cerveau d’un fetus de
“Gibbon, singe éminemment su-
“ périeur, et tellement rapproché dle
“ Porang, que des naturalistes trés-
“ corapétents lont rangé parmi les
“ anthropoides. M. Huxley, par ex«
“emple, n’hesite pas sur ce point,
“ Kh bien, c’est sur le cerveau d’un
““tatus de Gibbon que Gratiolet a
“vu les circonvolutions du lobe tem-
“ noro-sphénoidal déja développées
“ lorsqwil n’existent pas encore de plia
“ sur le lobe frontal, Il était donc
“)hien autorisé 4 dire que, chez
“homme les circonvolutions appa-
“ yaissent d’a en w, tandis que chez
“les singes elles se développend
“Vw ena.”

204 The Descent of Man. Part I,

* réduit, d’nilleurs dts cctte époque. Le reste de la surface cérébrale
* 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 aud inferi-r views of the hemi-
spheres, but not the inner view. It is worthy of note that the figure
ty no meuns bears out Graticlet’s description, inasmuch as the fissure
(nterotempo:al) on the posterior half of the face of the hemisphere is
Sarre marked than any of those vaguely indicated in the anterior half.
If the figure is correct it in no way justifies Gratiolet’s conclusion :
* T] yadone entre ces cerveaux [those of a Callithrix and of a Gibbon] et
* celui du foetus humain une diti¢rence fondamental. Chez celui-ci, long-
“tenips avant que Jes plis temporaux apparaissent, les plis frontaux
“ essuyent Vexister.”

Since Gratiolets time, however, the development of the gyri and
su'ci of the brain has been made the subject of renewed investigation
by Schmidt, Bischoff, Pansch,’* and more particularly by E-ker,’? whose
work is not ouly the latest, but by far the most complete, memoir on
tle subject.

The final results of their inquiries may be summed up as follows :—

1. In the human feetus, 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 bavkwards tar beyond the
cerebellum.

2. Vie 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 fave of the hemi-
sphere (whence doubtless Gratiolet, who does not seem to have examined
that fuce in his foetus, overlooked it), and is either the internal perpen-
dicular (occipito-parietal), or the cal-arine sulcus, these two being close
together and eventually running into one unother. As a rule the
occipito-parietal is the earlier of the two.

3. At the latter part of this period, another sulcus, the “ posterio,
parictal,” 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 (i ¢. p. 212-13, Taf. IL. figs. 1, 2, 3, 4), the antero-
temporal sulcus (seissure parallele) so characteristic of the ape’s brain,
ts 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 fcetal human brain is in
perfect harmony with the general doctrine of evolution, and with the

‘8 ‘Ueber die typische Anordnung 78 ¢ Zur Entwickelungs Geschichte
der Furchen und Windunger auf der Furchen und Windungen der
den Grosshirn-Hemispbiren des Grosshirn-Hemisphiren im Fretus
Menschen und der Affen.’? ‘Archiv des Menschen.’ ‘ Archiv fiir Anthroe
fer Anthropologie,’ iii., 18€8, pologie,’ iii, 18 48,

On vp. VIL Structure of the Brain. 205

view that man has bern evolved from some ape-like form ; though there
ean be no dondt that that form was, in many respects, different from
any member of the Primates now living.

Von Buer taught us, half x century ago, that, in the course of their
development, allied animals put on, al 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, {uasmuch as at one period of its life the tadpole has all the cha-
racters of a fish, and, if it went no further, would have to he 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 a1
Arctwpithecine or marmoset-like ape; for its hemispheres, with their
great posterior lobster, aud with no sulci but the sylvian and the
calearine, present the characteristics found only in the group of the
Arctopithecine Primates. But it is eqnally 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 Platyrhini
proper, the only observation with which I am acquainted is due to
Pansch, who found in the brain of a fcetal Cebus Apella, in addition to
the sylvian fissure and the deep calearine fissure, only a very shallow
tnterotemporal fissure (se/sswre puralléle of Gratiolet.)

Now this fact, taken together with the circumstance that the ant«ro-
temporal sulcus is present in such Platyrhini 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 govs,
affords fair evidence in favour of Ghratiolet’s hypothesis, that the
posterior sulci appear belore the anterior, in the brains of the
Platyrhini. But, it by no mcans follows, that the rule which may hold
good for the Platyrhini extends to the Cuturhini. We have wo in-
formation 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 nut w shadow of evidence to shew
that the sulci of a chimpanzee’s, or orang’s, brain do not appear in the
sume order as a man’s.

Gratiolet opens his preface with the aphorism. “Il est dangerenx
“dans les sciences de conclure trop vite.’ I fear he must have for-
go.ten this sound maxim by the time he had reached tle 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 Foy example, M. l’Abbé Lecomte winisme et Vorigine de Homme
in his terrible pamphlet ‘Le Dar- 1873.

206 The Descent of Man. Part I.

But it is important to remark that, whcther Gratiolet was right or
wrong in his hypotaesis respccting the relative order of appearance of
the temporal and frontal sulci, the fuct remains; that, before either
temporal or frontal sulci, appear, the foetal brain of man presents
characters which are fuund 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 bas resulted from the gradual modifica
tion of the same form as that trom vhich the other Primates have
epIung.

(| 207 )

Part It.
SEXUAL SELECTION.

CHAPTER VIII.
PrincipLes oF SEXUAL SELECTION.

Secondary sexual characters—Sexual selection—Manner of action—Ex-
cess of males—Polygamy—tThe male alone generally modified through
sexual selection—Kagerness of the male—Variability of the male—
Choice exerted by the female—Sexual compared with natural selection
—Inheritance, at corresponding periods of lite, 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 charac-
ters, which are not directly connected with the act of reproduc-
tion; 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 hersecurely. 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
vossible to decide which ought to be called primary and which
secondary.

‘The female often differs from the male in having oigans for the
nourisiimcnt or protection of ber young, such as the mammary

208 The Descent of Man. Pari Il.

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
cva in certain male fishes, and those temporarily developed in
certain male frogs. The females of most bees are provided with
@ special apparatus for collecting and carrying pollen, and their
ovipositor is modified into a sting for the defence of the larve
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 with is 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 rerroductive functions. Thus the females
of certain flies (Culicide and Tabanide) are blood-suckers,
whilst the males, living on flowers, have mouths destitute of
mandibles. The males of certain moths and of some crustaceans
(e.g. Tanais) have imperfect, closed mouths, and cannut 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 (Curcu-
liouida) there is a great difference between the male and female
in the length of the rostrum or snout ;? 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

1 Westwood, ‘Modern Class. of 2 Kirby and Spence, ‘Introduc-
Insects,’ vol. ii, 1840, p. 541. For tion to Entomology,’ vol. iii, 1826,
the statement about Tanais, men- p. 309.
tioned below, I am indebted to Fritz 3 ‘Birds of New Zealand,’ °972,
Muller. p. 66.

Car. VITL Sexual Selection. 209

that the male uses his strong beak in chiselling the larve 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
fur 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 inheritanee 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
puribus, 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 loco.wotion, 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 orgaus 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 tneir
legs and antenne modified in an extraordinary manner for the
prehension of the female; hence we may suspect that it is bk>-
cause 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

15

210 The Descent of Man. Pant I

like a rasp, and with this they coil round and permanently hold
the females.’

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
#n 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
ior 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, Jocomotive, 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 pro-

4M. Perrier advances this case
(‘Revue Scientifique,’ Feb. 1, 1873,
p. 865) as one fatal to the belief in
sexual selection, 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 untlerstand even the ‘irst
principl2s 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 J not met with this remark, |
should not have thought it possible
for any one to have read this chapter
and to have imagined that I main-
tain that the choice of the female
had anything to do with the develop.
ment of the prehensile organs in thi
male,

Snav. VIII Sexual Selection. 211

ducing vocal or instrumental music—and their glands for
emitting odours, most of these latter structures serving only te
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
wnornamented, 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 per-
torming 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 breed 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, how-
ever 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 ag 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 thé 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 here-
after, 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
nultiform and complex associated ideas. A more just com-
parison 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 w

212 The Descent of Man.

Parr Lf,

which sexual selection acts is somewhat uncertain. Neverthe-
less if those naturalists who already believe in the mutability ot
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 wovld
be superfluous to give instances. Hence the females have the
opportunity of selecting one out of several males, on the suppo-
sition 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 nightin-
gale 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. 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 he 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.°
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

5 J, A. Allen, on the ‘Mammals
and Winter Birds of Florida,’ Bull.
Comp. Zoology, Harvard College, p.
268.

8 Even with those plants in which
the sexes are separate, the male
flowers are generally mature be-
fore the female. As first shewn
bv C. K. Sprengel, many her:naph-

rodite 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 casea
in which the female organs are
beforehand.

Guar. VIL. Sexual Selection. 213

would tend to inherit similar instincts and constitutions. I+
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 understand-
ing 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-eudowed 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.’ The
males, as we have seen, are generally ready to breed before the

7 Here is excellent evidence on an experienced ornithologist. Mr
the character of the offspring from J. A. Allen. in speaking (‘ Mammile

The Descent of Man. Part II.

214

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, be-
cause they are the first to breed. Such vigorous pairs would
surely rear a larger number of offspring than the retarded
females, which would Le 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.®
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 at-
tractive. 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 aud 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 bad 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 advan-

to those female bees which are the
first to emerge from the pupa each
year. See his remarkable essay,

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 sea-
“ son. In cases where several broods
“ are reared each year, as a general
“yule the birds of the eariier broods
“ seem in all respects the most per-
« fect and vigorous.”

§ Tlermann Miler has come to
this same conclusion with respect

‘Anwendung den Darwin’schen Lehre
auf Bienen,’ ‘Verh. d. V. Jahrg.’
xxix, p. 45,

® With respect to poultry, I have
received intormation, hereafter to
be given, to this effect. Even with
birds, such as pigeons, which piir
for life, the female, as I hear frem
Mr. Jenner Weir, will desert het
mate if he is injured or grows weak

Crap, VIIT. Sexual Selection. 215

tage 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 pre-
ferred 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 con-
siderably 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 propor-
tional 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 in-
equality 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, ButI 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 proportion
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 few years of infuncy, 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

216 Lhe Descent of Man. Part IL

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 larve 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 ina
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 num-
bers 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 at-
tractive males previously produced would still have at least as
goo. 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

Cuar, VILL. Sexual Selection.

217

polygamous, but with animals belonging to the lower classes 1
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 Mycefes curaya 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 capueinus differs somewhat from the female, and
appears to be polygamous.” 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 Anzdlope saiga
appears to be the most inordinate polygamist in the world ; for
Pallas" 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 polygamons, 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

10 On the Gorilla, Savage and
Wyman. ‘Boston Journal of Nat.
Hist.’ vol. v. 1845-47, p. 423, On
vynocephalus, Brehm, ‘Illust. Thier-
leben,’ B. i. 1864, s. 77. On My-
cetes, Rengger, ‘Naturgesch,: Siuge-
thiere von Paraguay, 1830, s. 14,
20. Cebus, Brehm, ibid. s. 108.

1 Pallas, ‘Spicilegia Zoolog.,’

Fase. 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 gre
garious,

218 The Descent of Man. Pant II

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’? 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.% 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
eolour..4 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 Péron, 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 hy even a

12 Dr. Campbell, in ‘ Proc. Zoo- 18 Dr, Gray, in ‘Annals and
fog. Soc,’ 1869, p. 138. See alsoan Mag. of Nat. Hist.’ 1871, p. 302.
interesting paper, by Lieut. John- 4 See Dr. Dobson’s exvellent

stone, in ‘Proc. Asiatic Soe. of ' paper, in ‘Proc. Zoolog. Suc.’ 1873
Bengal,’ May, 1868. p. 241,

Cnap. VIIL Sexual Selection.

219

greater number of females. It is an interesting fact, as Dr.
Gill remarks, 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
“ Jarger 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. Iam informed
by Mr. Wallace that the like is true of the Chatterers or
Cotingide: 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 fortheir 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.’ 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 caye of polygamy or polyandry has not been
ascertained.

The Gallinacese exhibit almost as strongly marked rexual
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 mono-
gamous guinea-fowl or partridge! Many similar cases could be
given, as in the grouse tribe, in which the males ot the poly-
gamous 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 dif-
ferences, and the great bustard (Otis turda) is said to be poly-
gamous. With the Grallatores, extremely few species differ
sexually, but the ruff (Machetes puynax) affords a marked

18 The Eared Seals, ‘ American
Naturalist,’ vol. iv., Jan. 1871.

'6 <The Ibis,’ vol. iii. 1861, p.
133, on the Progne Widow-lird.
See also on the Vidua azxillcris,
bid. vol. ii. 1860, p. 211. On the
wlygumy of the Capercailzie and

Great Bustard, see L. Lloyd, ‘Game
Birds of Sweden,’ 1867, p. 19, and
182. Montagu and Selby speak of
the Black Grouse as polygamous
and of the Red Grouse as mono-
gamous,

220 The Descent of Man. Part II,

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 hag had very large experience with
birds, whether the male tragopan (one of the Gallinaces) was
polygamous, and I was struck by his answering, “I do not
“ know, but should think so from his splendid colours.”

1t 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 ina 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 ;!’ 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 ad-
vantage thus gained by the more vigorous pairs in rearing a
larger number of offspring has apparcntly sufficed to render
sexual selection efficient. Buta large numerical preponderaace

i7 Novel Humphreys, ‘ River Gardens,’ 1857.

Cnap, VIII. Sexual Selection. 221

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 de=
struction of the females; or whether it indirectly follows from
the practice of polygamy.

The Male generally move 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
moditied ; 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 here-
after. That the males of all mammals eagerly pursue the
females s 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.” 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.”

18 Kirby and Spence, ‘Introduc- females of this species are impreg-

tion to Exiomology,’ vol. iii. 1826,
p. 342,

1® One parasitic Hymenopterous
insect (Westwood, ‘ Modern Class. of
Insects,’ vol. ii. p. 160) forms an
exception to the rule, as the male
fas rudimentary wings, and never
quits the cell in which it is born,
whilst the female has well-develeped
wings. Audouin believes that the

nated 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 interbreeding is thus avoided.
We shall hereatter meet in various
classes, with a few exceptional vases,
in which the female, instead ot’ tha
male, is the seeker aad wooar.

222 The Descent of Man. Part I.

The female, on the other hand, with the rarest exceptions, is
less eager than the male. As the illustrious Hunter” 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 inale. Every observer of the habits of animals will be able
to call to mind instances of this kind. It is shown 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 thun the female, so
that he searches for her, and plays the more active part in court-
ship. 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 fertili-
sation 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 Alege, &c., by the loco-
motive 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 re-
spect, analogous with plants.” 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
tose in the scale and became locomotive, should retain the same
habit; and they would approach the female as closely as pos-
sible, in order not to risk the loss of the fertilising element in a
fong passage of it through the water. With some few of the lower

% ¢ Assays anil Observations.’ of the male and female reproductive
edited by Owen, vol. i. 1861, p. cells, remarks, ‘‘ verhalt sich die
94, “eine bei der Vercinigung activ,

21 Prof. Sachs (‘Lehrbuch der “.. . die andere erscheint kei der
Botanik, 1870, ». 633) in speaking “ Vereinigung passiv.”

Cuar, VIL Sexual Selection. 7: 223

animus, 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 acquire-
meut 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.” Good evidence also
in favour of this conclusion can be produced by a comparison
of the two sexes in mankind. During the Novara Expedition”
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,” 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 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” 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

22 ¢ Vortrage iiber Viehzucht,’ my ‘Variation of Animals and

1872, p. 63.

23 ¢ Reise der Novara: Anthro-
polog. Theil, 1867, s. 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 cl durmesticated animals. see

Plants under Domestication,’ vel, ii.
1868, p. 75.

24 ¢ Proceedings Royal Soc.’ vol.
xvi. July 1868, pp. 519 and 524,

25 «Proc, Royal Irish Academy,
vol. x. 1868, p. 123.

26 «Massachusetts Merlical Soe.'
vol, ii. No. 3, 1°68, p. 9.

224 The Descent of Man. Part IL

that women would more frequently endeavour to conceal a
deformity of thiskind than men. Again, Dr. L. Meyer asserts that
the ears of man are more variable in form than those of woman.”
Lastly the temperature is more variable in man than in woman.”
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 in-
dependently of selection the two sexes, from differing constitu-
tionally, tend to vary in a somewhat different manner. The
female las 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, &c.: 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 dif-
ference from the female.” 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.*? 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. Never-
theless, they may become permanent if the exciting cause acts

27 (Archiv fiir Path. Anat. und
Phys.’ 1871, p. 488.

28 The conclusions recently ar-
rived at by Dr. J. Stockton Hough,
on the temperature of man, are
given in the ‘Pop. Science Review,’
Jan. Ist, 1874, p. 97.

29 Prof. Mantegazza is inclined
to believe (‘ Lettera a Carlo Darwin,’
‘Archivio per 1’ Anthr opologia,’
1871, p. 306) that the bright
colours, common in so many male
animals, are due to the preseuce

and retention by them of the sperm-
atic fluid; but this can hardly be
the case; for many male birds, fur
instance young pheasants, become
brightly coloured in the autumn of
their first year.

30 For mankind, see Dr. J. Stock-
ton Hough, whose conclusions are
given in the ‘ Pop. Science Review,’
1874, p. 97. See Girard’s observae
tions on the Lepidoptera, as given
in the ‘ Zoological Record,’ 1869, p.
347,

Onar. VILL. Sexual Selection. 225

permanently ; and in accordance with a frequent forin of inheri-
tance 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 speci-
mens 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, &c., between the two regions. Now, in some
few cases, the two sexes of the same species appear to have been
differently affected ; in the Age/ceus pheeniceus the males have had
their colours greatly intensified in the south; whereas with Car.
dinalis 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.®

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 some-
times 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 beauti-
ful 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 plausi-
bility, that there has been a double or mutual precess of sexual
selection; the more vigorous and precocious females selecting
the more attractive and vigorous males, the latter rejecting all
except the move attractive females. But from what we know

U ¢ Mammals and Birds of E. Florida,’ pp. 234, 280, 295,
16

226 The Descent of Man. Part Li.

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
hy one sex, generally the male, and then transmitted to the off-
spring of both sexes. If, indecd, 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 vrna-
ments, and yet the members of both sexes or of one alone have
probably acquired simple colours, such as white or black, throngh
sexual selection. The absence of bright tints or other ornaments
may be the result of variations of the right kind never having
ceeurred, 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 tho
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 poly-
gamous, obtains fewer females ; so that they leave fewer, less vigor-
ous, 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 goon. This circumstance may partly account for
the ficguent and extraordinary amount of variability presented

Cuap. VILL Sexual Selection. 227

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 conquer-
ing 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
impurtant 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 mauy classes, and in the course of ages has producea
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 dis-
tinction 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 trans-
mits the characters proper to its own male and femalesex to the
hybrid offspring of either sex. The same fact is likewise mani-
fest, when characters proper to the male are occasionally deve-
loped 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

228 The Descent of Man. Pagr TL

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 de-
velopment of characters in the female and of transference to the
male, is less frequent; it will therefore be well to give one strik-
ing.instance. With bees the pollen-collecting apparatus is used
by the female alone for gathering pollen for the larve, 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.* Ags 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 bers
primordially collected pollen as well as the females; although
we have some reason to suspect that male mammals primordially
suckled their young as wellas 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 deveiopment 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 of 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 Lifé-—This tendency
1s 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 re-
appear in the offspring at the same advanced age. When devia-
tions 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,3 I will

32H. Muller, ‘Anwenduag der 33 «The Variation of Animals

Darwin’schen Lehre,’ &c. Verh. and Plants under Domestication,’
dou. V. Juhrg. xsia. p. 42. vol. ii. 1868, p. 75. In the. last

Onav. VII, Sexual Selection. 229

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 theia
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 plu-
mage, “ 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.* 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; yct 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,® 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

chapter but one, the provisional
hypothesis of pangenesis, above
alluded to, is fully explained.

34 These facts are given on the
high authority of a great breeder,
Mr. Teebay ; see Tegetmeier’s ‘ Poul-
try Book,’ 1868, p. 158. On the
characters of chickens of different
breeds, and on the breeds of the
pigeon, alluded to in the following
parngraph, see ‘ Variation of Ani-

mals,’ &c., vol,
vol. ii. p. 77.

35 * Nove species Quadrupedum e
Glirium ordive,’ 1778, p. 7. On
the transmission of colour by the
horse, see ‘ Variation of Animals,
&c., under Domestication,’ vol. i. p.
51. Also vol. ii. p. 71, for a gene-
ral discussion on ‘Inheritance ar
limited uy Sex.’

pp. 160, 249;

230 The Descent of Man. Parr II.

is transmitted, yet it probably is s°, as all shades of colour are
strongly inherited by the horse. Nor is this fori of inheritance,
as limited by the seasons, more remarkable than its limitation
by age or sex.

Inheritance as Limited by Sea —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
trom those of the female; and these differences, acquired under
domestication, are regularly transmitted to the same sex. Asa
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-brecds of the fowl in which the males can hardly be
distinguished from one another, whilst the females differ con-
siderably in colour. The scxes 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
temale.*® 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 opposi-
tion to, the wish of the breeder.

Most of our domestic races have been formed by the accumula-
tion 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

36 Dr. Chapuis, ‘Le Pigeon Voya- similar differences in certain breeds
geur Belge,’ 1865, p. 87. Boitarc at Modena, ‘Le variazioni dei
et Corbie, ‘ Les Pigeons de Volitre,’ Colombi domestic,’ del Paolo Bo
Ge, 1824, p. 173. See, also, cn niasi, 1873.

Cuap. VILL Sexual Selection

231

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 sub-
sequently transferred it to the males. All these cases are in-
telligible 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 i 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, how-
ever, 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
sitnilar 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
origmally limited, the process would be extremely difficult, per-
haps impossible.%”

37 Since the publication of the
first edition of this work, it has
been highly satisfactory to me to
and the following remarks (the
Field,’ Sept. 1872) from so ex-

perienced a breeder as Mr. Teget-
meier, After describing some cu-
rious cases in pigeons, of the trans-
mission of colour by one sex alune,
and the formation of a sub-breed

232 The Descent of Man. Pare IT.

On the Relation betueen 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 charac-
ters 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
strie, though transmitted through the female, should be deve-
loped 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 su-
pernumerary digits, colour-blindness, &c., 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 wellas throagh the same sex. 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 as it has an important bearing on sexual selection,
I must here enter into lengthy and somewhat intricate details.

lt 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 ditfers in the same manner from
the young of both sexes. The generality of this fact is quite
remargable: it holds good with almost all mammals, birds,

with this character, he says: “It is ‘“ facts that I have related; but it
“a singular circumstance that Mr. “is remarkable how very closely
“ Darwin should have suggested the “ he suggested the right method of
“ possibility of modifying the sexual “ procedure.”

“colours of birds by a course of 38 References are given in my
“artificial selection, When he did = Variation of Animals under Domes.
“«2, he was in ignorance o1 these tication,’ vol. ii. p. 72.

Snar. ViIT. Sertual Selection. 233

amphibians, and fishes; also with many crustaceans, spiders, and
some few insects, such as certain orthoptera and libellule. 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, ou 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
aud 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 m 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 cach 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 varia-
tions 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 thece
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
oly 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 spccies the horns ought to appear later in Jife, which

The Descent of Man. Pier Tl

234

would lead to their development in that sex alone, in whick
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 nite
mouths after birth in the roebuck, to ten, twelve or even more
months in the stags of the six other and larger species.° 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.
oreus), 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, con-
sidering 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,"
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

38 T 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 Breadal-

bane. In regard to Fallow-deer, I
have to thank Mr. Eyton and
others for information. For the

Cerius atces of N. America, see
‘Land and Water,’ 1868, pp. 221
and 254+ and for the C. lirginianus
anid strnjy' ceros ot the same con-

tinent, see J. D. Caton, in ‘Ottawa
Acad. of Nat. Sc. 1868, p. 13. For
Cervus Eldi of Pegu, see Lieut,
Beavan, ‘Proc. Zoolog. Soc.’ 1867,
p. 762.

40 Antilocapra Americana. I have
to thank Dr. Canfield for informa-
tion with respect to the horns of the
female: see also his paper in ‘ Proc,
Zoolog. Soc,’ 1866, p. 109. Alse
Owen, ‘Anatomy of Vertubrates,
vol. iii. p. 627.

Cuar. VIII. Sexual Selection.

235
we do know with respect to the horns of deer, cattle, &c., 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 scen, at birth or soon
afterwards." 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,” 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 pro-
tuberances so common on the heads of birds, and he cones
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 cared
pheasant (Crissuptilon 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

41 J have been assured that the however, a breed of sheep in which,

horns of the sheep in North Wales
can always be felt, and are some-
times 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.

42 T am greatly indebted to Prof.
Victor Carus for having made en-
quiries for me, from the highest
authorities, with respect to the
merino sheep of Saxony. On the
Guinea coast of Africa there is,

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 ac-
curred at a later period of life than
in Welsh sheep, in which both sexes
are horned.

43 «Ueber die knéchernen Schadel-
hocker der Végel’ in the ‘ Nieder-
landischen Archiv fur Zoologie,'
Band I. Heft 2, 1872.

236 The Descent of Man. Parr IL,

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.* 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 ssmewhat 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.“° 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

‘4 In the common peacock (Pavo
cristutus) the male alone possesses
spurs, whilst both sexes of the Java
Peacock (P. muticus) offer the un-
usual 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 pre-
vious year, of both species, com-
pared on April 23rd, 1869, there
was uo difference in the develop-
ment of the spurs. The spurs,
however, were as yet represented
merely by slight knobs or eleva-
tions. . I presume that I should
have been informed if any difference
in the rate of development had
deen observed subsequently.

‘5 In some other species of the
Duck family the speculum differs
“wa greater deg.ce in the two

sexes; but I have not been able to
discover whether its full develop-
ment 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 d/ergus cue
cullatus we have, however, a case of
this kind: the two sexes differ con-
spicuously 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 dif-
ferences: see Audubon, ‘ Ornitho-
logical Biography,’ vol. iii, 1835,
pp. 249-250.

Sua VILL. Sexual Selection. 237

to one sex, whilst others are common to bothsexes. A difference
of this kind in the period of developmeut is not so improbable as
it may at first appear; for with the Urthoptera, which assume
their adult state, not by a single metamorphosis, but by a snc-
cession 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, re-
latively 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 super-
numerary 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 trans-
mitted 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 develop-
ment 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
und 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 in-
sreased 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
tule. There is a breed of pigeons in which the males alone are

238 The Descent of Man. Part IL

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
‘n 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,** 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 charac-
ters by one or both sexes, seems gencrally 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 rerders it probable that their
colours first appcared 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
ifamburegs, however, offer a partial exception; for the two sexes,
though not quite alike, resemble each other more closely than

** «Das Ganze der Taubenzueht,’ puis, ‘Le pigeon voyageur Belge,
1827, s. Yl, 24. For the case of 1863, p. 87,
the strerked pigeons, see Dr. Cha-

Caar. VILL Sexual Selection. 239

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 trans-
mitted 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 ;*7 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 dis-
cussion 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

47 For full particulars and re- 250, 256. In regard to the higher
ferences on all these points respect- animals, the sexual differences which
ng the several breeds of the Fowl, have arisen under domestication are
see ‘ Variation of Animals and Plants described in the same work uadez
ander Domestication,’ voi. i. pp. the head of each species,

240 The Descent of Man. Parr IL.

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 trans-
mitted to the same sex at the same age, the other sex and tho
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 modi-
fied, 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 charac-
tors 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 ta
vary in a manner which would not only have been of no use ta
them at an carly age, but would have been actually injurious—

Snap, VIII. Sexual Selection. 241

as by acquiring bright colours, which would render them con-
spicuous 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, Conse-
quently 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 late in life, and transmitted to one
sex alone, have incessantly been taken advantage of and accumu-
lated 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 accumu-
lated 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 havirg arisen at a late period of life, have been

17

242 The Descent of Man. Par IL

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 animuls
belonging to various clusses,

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 1045 males to 100 females. But in 1857 the
male births throughout England were as 105-2, and in 1865 as
1040 to 100. Looking to separate districts, in Buckingham-
shire (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 1062 to 100. Taking a still smaller district, viz., Rut-
landshire (where the annual births average only 739), in 1864
the malo births were as 114°6, and in 1862 as only 97:0 to
100; but even in this small district the average of the 7345
births during the whole ten years, was as 104-5 to 100; that is in
the same ratio as throughout England.* The proportions are
sometimes slightl} disturbed by unknown causes; thus Prof

“ <Twenty-rinth Annual Report In this report (p. xii.) a special de
of the Reyistrr-General for 186.’ cennial table is given.

Onap, VIII. Proportion of the Sexes

243

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
fiuring 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.% 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 decide ily 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.

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 1846 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.” 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

49 For Norway and Russia, see 343. Dr. Stark also remarks

abstract of Prof. Faye’s researches,
in ‘British and Foreign Medico-
Chirurg. Review,’ April, 1867, pp.
343, 345. For France, the ‘ An-
nuaire 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 propor-
tion of the sexes. :

5° In regard to the Jews, see M.
Thury, ‘La Loi de Production des
Sexes,’ 1863, p. 25.

51 ¢British and Foreign Medico-
Chirurg. Review,’ April, 1867, p.

(Tenth Annual Report of Births,
Deaths, &c., in Scotland,’ 1867, p.
xxviii.) that “These examples may
“ suffice to shew 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, how-
“ever, 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-
“ yate is an impressed, natural, and
“ constitutional peculiarity due te
“ sex alone.”

The Descent of Man. Parr IL.

244

variable iv structure than the female; and variations in im-
portant 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 pumerous; and, asa highly competent judge,
Dr. Crichton Browne,” 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 sub-
sequently, 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.

It seems at first sight a mysterious fact that in different
nations, under different conditions and climates, in Naples,
Prussia, Westphalia, Holland, France, England aud the United
States, the excess of male over female births is less when they
are illegitimate than when legitimate." This has been explained by
different writers iu many different ways, as from the mothers
being generally young, from the large proportion of first preg-
nancies, &c. 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, &c., 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

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 ‘s born smaller
than man; see Dr. Duncan, ‘ Fe-
cundity, Fertility, Sterility,’ 1871,
p. 3882,

4@ With the sayage Guaranys of

differ in size at birth. Thus

Paraguay, according to the accurate
Azara (‘ Voyages dans 1l’Ameriyque
merid.’ tom. ii. 1809, p. 60, 179),
the women are to the men in the
proportion of 14 to 13,

5+ 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 Registrai-Genera
for 1866,’ p. xv.

Cuap, VILL Proportvon of the Sexes. 245

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 determines the sex of the offspring ; and Prof. Leuckart™
has advanced what he considers sufficient evidence, with respect
to man and certain domesticated animals, that this is one impor-
tant 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 observa-
tions discountenance this belief. According to Dr. Stockton-
Hough,** the season of the year, the poverty or wealth of the
parents, residence in the country or in cities, the crossing of
foreign immigrants, &ec., 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’ 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 perind 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,** cou-
sisting 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, tle two sexes are produced in almost equal
numbers.

The fluctuations in the proportions during successive years

55 Leuckart (in Wagner ‘ Hand-
worterbuch der Phys.’ B. iv, 1853,
LD 774,

58 Social Science Assoc. of Phila-
dalphia, 1874.

57 « Anthropological
April, 1870, p. eviii.

58 During eleven years a record
was kept of the number of mares
which proved barren or prematurely
slipped their foals; and 1t deserves

Review,’

notice, as shewing how infertile
these highly-nurtured and rather
closely-interbred animals have be-
come, 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.

246 The Descent of Alan. Past lL

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 18:7 as unly 92°6 to 100 females. In the tabulated
returns the proportions vary in cycles, for the males exceeded the
females during six successive years; und the females exceeded the
maies during two periods each of four ycars: this, however, may be
acciden‘al; at least I can detect nothing of the kind with man in the
dvceunial table in the Registrar’s Report for 1866.

Dogs.—During a periud of twelve years, from 1857 to 1868, the birtha
of a large number of greyhounds, throughout England, were sent to
the ‘ Ficld’ newspaper; and I am again indebted to Mr. Tegetmeier for
curefully tabulating the results. The recorded births were 6878.
consisting of 3605 males and 3273 females, that is, in the proportion of
1101 males to 100 females. The greatest fluctuations occurred in
1854, 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 cause of the greyhound, but whether it
would hold with other domesticated breeds is in some degree doubtful.
Mr. Cupples has enquired trom several great breeders of dogs, and finds
that all without exception believe that f-males are produced in excess ;
but he suggests that this belief may have arisen from females being
iiss valued, and from the consequent disappointment producing a
slronger impression on the mind,

Sheep.—The sexcs of sheep are not asecrtain d by agriculturists until
severnl months after birth, at the period when the males are castrated ;
so thit the following returns do not give the proportions at bith.
Moreover, I find that several great breeders in Scotland, who annually
raise some thousand sheep, are firmly convinced that a larger proporticn
of males than of females die during the first year or two. Therefore the
proportion of 1nales would be somewhat larger at birth than at the age of
castration, ‘This is a remarkable coincidence with what, as we | ave
acen, occurs wilh mankind, and both cases probably depend on the
sume cause, | 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 8°65 births, consisting of
4407 males and 4558 jemales; that is in the proportion of 96 7 males to
100 females. With respect to Cheviot and black-faccd sheep bred in
Scotland, | have received returns from six breeders, two of them on a
large scale, chiefly fur the years 1867-1869, but some of the returns
extend back to 1862. The total number recorded amounts to 50,685,
consinting 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 femules, or as 97°7 to 100. So that with cheep at the
age of castration the females are certainly in excess of the mules, but
probably this would not hold good at birth.5®

Of Cattle I have rcc.ived returns from nine gentlemen of 982 births,
too few to be trusted; these consi:ted of 477 bull-calves and 505 cow-

58 [ am much indebted to Mr.
Cupples for having procured for me
the above returns from Scotland, as
well as some of the following re-
turns on cattle. Mr, R. Elliot of
Laighwoed, first called my atten-

tion to the premature deaths of the
males,—a statement snbsequently
confirmed by Mr. Aitchison and
others. To this latter gentleman,
and to Mr, Payan, I owe my thunks
tor large returus as to sheep.

‘nap, VIII Proportion of the Sexes. 247

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 44 calves born on a farm in
Derbyshire only one was a bull, Mr, Harrison Weir his enquired from
several breeders of Pigs, and most of thein estimute the male to the
female births as about 7 to 6. This same gentleman has bred Labbits
for many yeurs, and has not‘ced that a far greater number of bucks are
produced than does. But estimations are of little value.

Of mammalia in a state of nature T have been able to learn very
little. In regard to the common iat, I have received confl cting
statements. Mr. R. Eliiot, of Laighwood, informs me that a rat-catcher
assured him that he had ulways found the males in great excess, even
with the young in the nest. In consequence of this, Mr. Elliot
himself subsequently exumined some hundred old ones, and found the
statement true. Mr. F. Buckland has bred a Jarge number of white
rats, and he also believes that tle males greatly exceed the females,
In regard to Moles, it is said that ‘the males are much more numerous
“than the females ;” © and as the catching of these animals is special
occupation, the statement may perhaps be trusted. Sir A. Smith, in
describing an antvlope of 8. Afvica®! (Kobus sllipsiprymnus), remarks,
that in the herds of this and other species, the mal. s are few in number
compare w.ti the females: the natives believe that they are born in
this proportion; others b.-lieve that the younger males are expellel
from the herds, and Sir A. Smith says, that though le 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 beusts of prey of the
country.

BIRDS.

W.th respect to the Fowl, I have received only one account, namely,
that out of 1001 chickens of a highly-bred stuck of Covhins, reared
during eight years by Mr. Stretch, 487 proved males and 514 females;
ie, as 94:7 to 100. In regard to dumestiv pigeons tl ere is good
evidence either that the inales are produced in excess, or that they live
longer ; for these birds invariably pair, and single males, as Mr. ‘Teget-
meier infurms me, can always be purchased chcaper 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-le has often bred two cocks from the same nest,
and seldom two hens; moreover, the hen is generally the weaker of ihe
two, and more liable to perish.

With réspect to birds ina state of nature, Mr. Gould and others*?
are convinced that the males are generally the more numerous; anJ
as the young males of many species resemble the females, the latter
would naturally appear to be the more numerous. Laige 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 mules to one
female are generally produced. An experienced observer remarks, *?

60 Bell, ‘History of British Quad- iv. s. 990) comes to the same con-

rupeds,’ p. 100. clusion.
1 ¢ |]lustrations of the Zoology 83 On the authority of L. Lloyd,
of S. Africa,’ 1849, pl. 29. ‘Game Birds of Sweden,’ 1867, pp

® Brehm (‘ illust. Thierleben, B. 12, 132

Part IL,

248

Lhe Descent of Man.

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 thun females attend the leks or places of
courtship; but this latter circumstance is accounted for by some
observers by a griater number of hen birds heing killed by vermin,
From various facts given by White of Selborne,* it seems clear that
the males of the partridge must be in considerable execss in the south
of England; ani [ have been assured that this 1s the case in Scotland.
Mr. Weir on enquiring from the dealers, who receive at certain si asons
large numbers of rutis (Machetes pugnax), was told that the males are
mucl: 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 be was un-
hesitatingly answered by an old and trustworthy man, that with the
chaftiuch the males are in large excess; he thought as high as 2 mules to
1 female, or at least as high as 5 to 3.9 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 scxes are
about equal with the lark, the twite (Linaria montana), and goldtinch.
On the other hand, he is certain that with the common Jinnet, the
femules preponderate greatly, but unequally during different years ;
during some years lie has found. the females to the males as four to one.
It should, however, be Lorne in mind, that the chief season for catching
birds does net begin till Septeinber, so that with some species partial
migrations may have begun, and the flocks at this period often consist
of hens alone. Mr. Sulvin paid particular attention to the sexes of the
humming-birds in Central Ameiica, and he 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
Cumpylopterus hemileucurus were to the females as 5 to 2, and on
another ovcasion © 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 ap) earing greatly to exceed the female in number.” So
again with the Quiscalus major, Mr. G. Taylor® says, that in Florida
there were “ very few females in proportion to the males,” whilst in
Honduras the proportion was the other way, tle species there having
the character of a polygamist.

64 ‘Nat. Hist. of Selborne,’ letter
xxix. edit. of 1825, vol. i. p. 139.

6 Mr, Jenner Weir received
similar information, on making en-
quiries during the following year.
To shew the number of liviug chaf-
finches caught, I may mention that
in 1869 there was a match between
{wo experts, and one man caught
in a day 62, and another 40, male
cha.fnches.

The greatest number

ever caught by one man in a single
day was 70.

88 ‘Ibis,’ vol. ii. p. 260, as quoted
in Gould’s ‘Trechilide,’ 1861, p.
52. For the foregoing proportions,
I am indebted to Mr. Salvin for a
table of his results.

87 ‘This,’ 1860, p. 137; and 1867
p. 369.

88 ‘This,’ 1862, p. 137

Cuap. VIII. Proportion of the Sexes.

249

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.” Infertile
‘amales might readily be mistuken for males, as Dr. Giinther has
remarked to me in regard to trout. With some species the males are
believed to die soon after fertilising the ova. With many spec.es the
mules 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,” who has especially attended to the
natural histury of the pike (Hox lucius), states that many males, owing
to tueir 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 tu be largely in excess. Thus Mr. R. Buist, the superin-
tendent 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 mules to the females. We had at the outset at least ten males
“to one female.” Afterwards females sutticient for obtaining ova were
procured. He adds, “ from the great proportion of the males, they are
“constantly fighting and tcaring each other on the spawning-beds.”7!
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
“thefemales, It invuriably happens that when the first rush of fish is
“ mare to the net, there will be at least seven or eiyht 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 caiefully
searching the banks sufficient females for obtaising ova can be found.”
Mr. H, Lee informs me tht out of 212 trout, taken for this purpose in
Lord Portsmouth’s park, 150 were males and 62 females.

The males of the Oyprinide 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 spawuing-beds the males are ten
tiwes as numerous as the females; when a femule comes amongst the

6° Leuckart quotes Bloch (Wag-
ner, ‘Handwérterbuch der Phys.’
B. iv. 1853, s. 775), that with fish
there are twice as many males as
females.

7 Quoted in the ‘Farmer,’ March

18, 1869, p. 369.

™ ¢The Stormontheld Piscicul-
tural Experiments,’ 1866, p. 23.
The ‘Field’ newspaper, June 29th,
1867.

7 «Land and Water,’ 1868, p. 41

450 The Descent of Man, Parr fl,

males, ‘she is immediately pressed closely by a male on each side;
“and when they have beer in that situation for a time, are superseded
* by otl.er two males,” 73

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, [ cannot
find that this has ever been done The general opinion appears to be
that the sexes are nearly equal, but in [taly, as I hear from Professor
Canestrini, many breeders are convinced that the females are produced
in excess, This same naturalist, however, informs we, 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 rezard to Butterflies in a state of nature, several observers have
been much struck by the apparently enormvus proponderance of the
males.74 Thus Mr. Bates,”* 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 propor-
tion of a lundred to one. In North America, Edwards, who had great
experience, estimates in the genus Papilio the mules to the females as
four to one; and Mr. Walsh, who informed me of this statement, says
that with P. turnus this is certuinly the case. In South Africa, Mr. R.
‘Trimen found the mules in excess in 19 species ;75 and in one of these,
which swarms in opin pluces, he estimated the number of males as
fifty to one female. With another species, in which the males are
numerous in certain localities, hie collected only five females during
seven years. In the island of Bourbon, M. Muillard states that the
males of one species of Papilio are twenty times as numerous as the
females.”7 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 per-
haps offer au exception. Mr. Wallace” stutes that the females of
Ornithoptera erasus, in the Malay archipelago, are more common anil
more easily caught than the males; but this is arare butterfly. I may

or four times as numerous as the

73 Yarrell, ‘ Hist. British Fishes,’
vol. i. 1826, p. 307; on the Cyprins
tarpio, p. 331; on the Finca vulgaris,
p. 331; on the Abramis braima, p.
336. See, for the minnow (Leu-
ciscus phoxinus), ‘ Loudon’s Mag. of
Nat. Hist.’ vol. v. 1832, p. 682.

74 Leuckart quotes Meinecke
(Wagner, ‘Handwiérteibuch der
Phys.’ B. iv. 1853, s, 775) that
the males of Butterfics sre three

females.

7% «The Naturalist en the Ama
zons,’ vol. ii. 1883, p. 228, 347.

78 Four of these cases are given
by Mr. Trimen in his ‘ Rhopalocera
Africe Australis.’

*T Quoted by Trimen, ‘ ‘Transact
Ent. Soc.’ vol. v. part iv. 1866, p, 330,

Transact. Linn. Soc,’ vol, xxv,
p. 37.

Cuap. VIIL Proportion of the Sexes. 251

here add, that in Hyperythra, a genus of moths, Guenée gays. that
from four to five females are sent’in collections from India tor one
euiale,

When this subject of the proportional numbers of the sexes of insects
was broug.t before the Entomological Society,” it was generally
admitted that the males of most Lepidoptera, in the adult or image
state, are cauglt 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 circumstunce is well known to occur with most Lepidoptera, «8
well as with other insects. So that, as M. Personnat remarks, the
males of the domesticated Bombyx Yamamai, are useless at the begin-
ning of the season, and the females at the end, from the want of
mates.8° I cannot. however, persuade myself that these canses suffice to
explain tl.e great excess of males, in the above cases of certvin butter-
flies which are extremely common in their native countries. Mr.
Stainton, who has paid very close attention during many years tu the
smaller moths, informs me that when he collected them in the imayo
state, he thouzht 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. Double-
day. however, and some others, take an opposite view, and a e con-
viuced that they have rared from the egys and caterpiilurs a larger
proportion of males than of feinales.

Besides the more active habits of the males, their earlier em rg nee
from the c.coon, and in some cases their frequenting more open
stutions, o.her causes may be assigned for an apparent or real difference
in the prop .riional numbers of the sexes of Lep:doptera, when cap-
turcd in the imago st..te, and when reared from the egg or cate:pil.ar
state. I hear from Professor Canestrini, that it is believed by many
brecders in Italy, that the female caterpillar of the silk-moth suffrs
more from tlie recent disease than the male; and Dr. Staud.nger
informs me that in reuring Lepidoptera mure females die in the
cocoon than ma'es. With many species the female caterpillar is larger
than the male, and a collector would naturally choose the finest
specimens, and thus unintentionally cullect a larger number of females.
Three cullectors have tuld me that this was their practice; but Dr.
Wallace is sure that most collectors take all the specimens which they
ean 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 im the first
brouds of the Ailanthus silk-motk, the wasps desti oy 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 1ois-
ture; and thus th:y would be exposed during a longer time tu
danger from ichneumons, birds, &c., and in times of scarcity would
perish in greater numbers. Hence it appears quire possible that

7 ¢Proc. Entomolog. Soc.’ Feb, ‘Proc. Ent. Soc.’ 3rd series, vol, v
ith, 1868. 1867, p. 487.
* Quoted by Dr. Wallace in

252 The Descent of Man, Parr I]

in a state of nature, fewer female Lepidoptera may reach maturity
than males; and for our special object we ure 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 1ound a single female, apparently indicates a
great excess of males, though this tact may perhaps be accounted for
oy the earlier emergence of the males from their cocoons. Mr.
Stainton informs me that from twelve to twenty males, may often be
sven congregated round a female Elachista rufocinerea. It is well
known that if a virgin Lastocampa quercus or Saturnia carpint
be exposed in a cage, vast numbers of males collect round her, and if
contined 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 hid been confined on the
previous day, and five males soon endeavoured to gain admittance.
In Australia, M. Verreanx, 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.*}

Mr. Doubleday has called my attention to M. Staudinger’s ® 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
(Heterucera) 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 tn 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 10U 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 Iam bound to add that Dr. Staudinger informs ine,
that he is himself of a different opinion. He thinks that the less active
hubits of the females and the earlier emergence of the males will
account for his collectors securing a larger number of males than
of femiules, and consequently for the lower prices of the former. With
respect to specimens r.ared from the caterpillar-state, Dr. Staudinger
believes. as previously stated, that a greater number of females than of
males die whilst confined in the cocoons. He adds that with certain
Bpevies one sex seems to preponderate over the other during certain

eurs.

2 Of direct observations on the sexes of Lepidoptera, reared either

§! Blanchard, ‘ Metamorphoses, 82 ¢ Lepidopteren - Doulletten
Meeurs des Insectes,’ 1868, pp. 225- Liste.’ Berlin, No. 2. 1866.
226. :

Onar. VILL. Proportion of the Sexes.

253

from eggs or caterpillars, I have received only the fw following
uses :—

| Males. | Females.
The Rev. J. Hellins*®* of Exeter reared, during 1868,)' 153 137
imagos of 73 species, which consisted of, . }
Mr. Albert Jones of Eltham reared, during 1868, 159 128
imagos of 9 species, which consisted of . . af;
During 1869 he reared imagos from 4 species, con-
sisting of . 2. . 2 ee : 8 a ive a
Mr. Buckler of Emsworth, Hants, during 1869, | 180 169
reared imagos from 74 species, consisting of. "}
Dr. Wallace of Colchester reared from one brood of | 59 48
Bombyx cynthia. . . . 6 ew ee "} ;
Dr. Wallace raised, from cocoons of Bombyx Pernyi | 994 123
sent from China, during 1869 . . . ti J
Dr, Wallace raised, during 1468 and 1869, from two}! 52 46
lots of cocoons of Bombyx yama-mai ww. } :
Total , 934 761

(

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 tv be
trustworthy.

On the whole, from these various sources of evidence, all pointing
in the same direction, I infer that with mst species of Lepidoptera,
the mature males generally exceed the femaies in number, whatever
the proportions may be at their first emergence from the egg.

With reference to the other Orders of insects, I have been able
to collect very little reliable information. With the stay-lee le
(Lucanus cervus) “the males appear to be much more numerous
“than the females;” but when, as Cornelius remarked during 1867,
un 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 Eluteridz. the males are said to be much more numerous than the
females, und * two or th ee ure often found united with one female :*
“so that here polyandry seems to prevail.” With Siagonium (Staphy-
linide), in which the males are furnished w.th horns, “t e females are
“ far more numerous than the opposite sex.” Mr. Janson stated at the
Entomological Society that the females of the bark- feeding Tomieus
villosus are s0 common as to be a plague, whist the males ure so rare
as to be hardly known.

84 Giinther’s ‘Record of Zoo-
logical Literature,’ 1867, p. 260.

83 This naturalist has been so
kind as to send me some results

from former years, in which the
females seemed to preponderate ;
yut so many of the figures were
estimates, that I {cund it impossible
to tabulate them.

On the excess of female Lucanus,
ibid. p. 250. On the males of Luca-
nus in England, Westwood, ‘ Modern
Class. of Insects,’ vol. i. p. 187. Ov
the Siagenium, ibid. p. 172.

254 Line Descent uf Man. Part IL

Tt 18 liard!y worth while saying anything about the proportion of
the sexes in certain speries urd even groups of insects, fur the males
are unknown or very rare, and the females are parthenogenetic, that
is, fertile with ut sexual union; examples of this are aftorded by
several of the Cynipide.®’ In all the gall-making Cynipide known
to Mr, Walsh, the females are four ur five times us nunicrous as the
males ; und so it is,as he informs me, with the gall-making Cec.domyiiea
‘Diptera), With some common species of Saw-flies (Tenthreding)
Mr. F. Smith has reared hundreds of specimens from lurve of all
sizes, but has never reared a single male: un the other hand, Curtis
says,®* that with certain species (Athalia), bred by him, the m: les 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 Miiller,*? collected a large number of
specimens of many s)ecics, and reared cthers from tle cocouns, and
counted the sexes. He found that the males of some species yieutly
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 ure at the
commencement of the breeding season practically in excess, Miiller
also ob.erved that the relutive number of the two sexes in sume
species differed much in d.fferent localities, But as H. Miiller has
limsclf remarked to me, these remarks must be received with
sole caution, as one sex might more easily escape ohservaticn than
the other. Thus his brother Fritz Miiller has noticed in Brazil that
the two sexes of the same species of bee sometimes frequent different
kinds of tlowers. With respect to the Orthoptera, I know hardly
anything about the relative number of the sexe.: Kérte,’* however,
says that out of 500 locusts which he examine:l, the males were to
the females as five to six. With the Neuroptera, Mr. Wal-h states
that in many, but by no means in all the species of the Odon.tous
group, there is a great overplus of males: in the genus Heterina, also,
the males are generally at least four times as numerous as the femules.
In certain species in the genus Gomplius the males ure equally in
excess, whilst in two other species, the females are twice or thri.e
as numcrous as the males. In some European species of Psocus
thousands of females may be collected without a single mule, whilst
with other species of the same genus both sexes are common.®® in
England, Mr. MacLachlan has captured hundreds of the female
Apataniu muliebris, but las never seen tle male; and of Horeus
hyemulis onty four or five males have been sien here? With m st
of thi se species (excepting the Tenthredine) there is at present no
evidence that the females are subject to parthenogenesis; and tlus we
sev how ignorant we are of the causes of the apparent discrepancy in
the proportion of the two sexes.

In t..e other Classes of the Articulata [ have been uble to collect still

** Walsh, in ‘The American En- derheuschrecke,’ 1828, p. 20.

tomologist,’ vol. i, 1869, p. 103. 89 ¢ Observations on N. American

¥. Smith, ‘Record of Zoologica’ Nenroptera,’ by H. Hagen and B.D.

Literature,’ 1867, p. 328. Walsh, ‘ Proc. Ent. Soc. Phila-
“6 + Harm [usects,’ pp. 45-46, delphia,’ Oct. 1863, pp. 168, 223,
87 « Anwenduag der Darwinschen = 229,

Vehrve Verh. d. a. V. Jahrg. axiv.’ #0 «Proc, Ent. Soc. London, Feb

"tne Strich, Zug oder Wan- 17, 1868.

Cuar. VIIL. Proportion of the Sexes. 255

less information. With Spiders, Mr. Blackwall, who has carefully
atiendcd to this class during many years, writes to me that the males
from their more erratic habits are more commouly seen, and therefore
appe. more numerous. This is avtually 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.2! ‘The small size of
the males in comparison with the females (a peculiarity which is some-
times curried to an extreme degree), and their widely ditterent appear-
ance, may account in some instances for their rarity in collections.”

sume of the lower Crustaceans are able to propagate their kind
asexu lly, and this will account for the extreme iarity of the males:
thus Von Siebold ** carefully examined no less than 13,000 specimens of
Apus from twenty-one localities, and amongst these he found only
31Y males, Wuiti: some other forms (as Tanais and Cypris), as Fritz
Miill-r informs me, there is reason to believe that the males are much
shorter-l.ved than the females; and this would explain their svarcits,
supposing the two sexes to be at first equal in number. On the o her
hand, Miller has invariably taken far mvure males than females of the
Diastylide and of Cypridina on the shores of Brazil; thus wit. a
species in the latter genus, 63 specimens caught the same day included
57 males; but he suggests that this prepondcrance may be due to
s:me unknown difference in the habits of the two sexes. With one
of the higher Brazilian crabs, niwely # Gelasimus, Fritz Miiller
found the males t) be more numerous than the females. Accurding
to the large experience of Mr. U. Spence Bate, the 1everse 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 nuturul 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 szven
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™ has recently found
on careful examination that the Todas, a hill-tribe of India,

*! Another great authority with O. P. Cambridge, as quoted in
respect to this class, Prof.Thorell of ‘Quarterly Journal of Science,’
Upsata (On European Spiders,’ 1868, p. 429.

1869-70, part i. p. 205) speaks as if 93 ¢ Beitrage zur Parthenogenesis,'

female spiders were generally com- p. 174.

moner than the males. *« ¢The Todas,’ 1873, pp. 190
% Sec, on this subject, Mr. 111, 194, 195,

256 The Descent of Man. Part [1

consist of 112 males and 84 females of all ages—that is in a ratio
uf 1833 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 illustra-
“tion 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
“ oreat, 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 80 ex-
tremely 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
states that he “has met with instances of women who have de-
“ stroyed four, siz, 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 Zea-
landers, 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 opera-
“tion during the years 1830 to 1844, when the non-adult
* population of 1844 was being preduced, 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

®§ Aboriginal Inhabitants of New Zealand; Government Report,’ 1859
bp. 36. .

Chap. VIIL Proportion of the Sexes. 257

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 1222 males to 100
females. It is more important for us that during this same
year of 1858, the vou-udulé 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 1U0. It may be added that in 1844, at
which period female intanticide had only lately ceased, the
nou-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,%* and as I have been informed by Bishop
Staley and the Rev. Mr. Coan. Nevertheless, another apparently
trustworthy writer, Mr. Jarves,*"’ 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 theIslands. A careful
census in 1889 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
12508 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,® the males of all ages

986 ‘Narrative of a Tour through 98 This is given in the Rev. H. T.
Hawaii,’ 1826, p. 298. Cheever’s ‘ Life in the Sandwich Is-
® ‘History of the Sandwich lands,’ 1851, p. 277.
telands,’ 1843, p. 93.

18

258 The Descent of Mun. Part Il

amount to 36,272, and the females to 33,128, or as 109-49 tc
100. The males under seventeen years amounted to 10,773, and
the females under the same age to 9593, or as 1123 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.”

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 sup-
posing 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 Jaw leading
to this result in decreasing races, which have already become

somewhat infertile.

8° Dr. Coulter, in describing
(‘Journal R. Geograph boc.,’ vol.
v. 1835, p. 67) the state of Cali-
fornia about the year 1830, says
that the natives, reclaimed by the
Spanish missionaries, have nearly
all perished, or are perishing, al-
though well treated, not driven
from their native land, and kept
from the use of spirits. He at-
tributes 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 ‘“ in-
“ fanticide, properly so called, is
“not common, though very fre-
“quent recourse is had to abor-
“tion.” If Dr. Coulter is correct
about infanticide, this case cannot
be advanced in support of Col.
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.

Thad hoped o grin some light

Besides the several causes previously

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, 1 know nothing of
the proportion of the sexes in any
breed, excepting greyhounds, and
there the male births are to the
female 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. There-
fore | am unable to decide whether
we can, on the above principles, ac-
count tor 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 eithet
sex to be destroyed, if there is any
cifference, the females are slightly
i? excess.

Cnap, VII. Proportion of the Sexes. 259

alluded to, the greater facility of parturition amongst savages,
and the less consequent injury te their male infants, would
tend to increase the proportion of live-born males to females,
Toere 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 com-
plication of causes, an indiscriminate though large destruction
of either sex would not tend to modity 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 ulti-
mately 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 pre-
ponderance of men in the tribe is sepposed 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

260 The Descent of Man. Parr IL

sve that the whole problem is so intricate that it is safer to leava
its solution for the future.

CHAPTER IX.

SECONDARY SEXUAL CHARACTERS IN THE LOWER CLASSES OF
THE ANIMAL KINGpom.

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.

WirH 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 at-
tached 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 cha-
racters, 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 (Actinie), some jelly-fish (Medusa,
Porpita, &c.), some Planariz, many star-fishes, Echini, Ascidians,
&c.; 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 thrcagh sexual selection

Cuap. IX, Sexual Selection. 261

It should be borne in mind that in no case have we suffi-
cient evidence that colours have been thus acquired, ex-
cept 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 indivi-
duals, 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, sexua! selection
will almost inevitably follow. We may, however, extend this
conclusion to both sexes, when coloured alike, if their colours are
}.'ainly 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 protec-
tion; 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 Meduse, or jelly-fishes, is of the
highest service to them as a protection; but when we are
reminded by Hackel that not only the meduse, 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! 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 ther tissues, independently of
any benefit thus derived. Ilardly any colour is finer than that
of arterial blood; but there is no reason to suppose that the
colour of the biood 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 Eolide (naked sea-slugs) is chiefly due to the biliary glands

1 ‘Archives de Zoolog. Expér.,’ Oct. 1872, p. 563.

262 The Descent of Man. Parr IL

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 vf
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
elasses, 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, bermaphroditism is not rare. In the next
higher class of the Gasteropoda, or univalve shells, the sexes are
cither 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 (/2ttorina 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
“ dobserver les amours des limacons, ne saurait mettre en doute
* la séduction déployée dans les mouvements et les allures qui
“ préparent et accomplissent le double embrassement de ces
“ hermaphrodites.” These animals appear also susceptible of
rome degree of permanent attachment: an accurate observer,

* «De l’Espéce tt de la Class. &c., 1869, p. 106.

Quare, IX. Molluscs. 263

Mr. Lonsdale, informs me that he placed a pair of land-snails,
(Helix pomatiu), 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 traci 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
cuttlefishes, 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.’ Certain
Cephalopoda, however, are characterised by one extraordinary
sexual character, namely, that the male clement 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, &c., 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 cxposed surfaces.* In some cases, as with shells

3 See, for instance, the account influence of light on the colours of
which I have given mm my ‘Journal a_ trordescent incrustation, de-
of Researches,’ 1845, p. 7. posited by the surf cn the coast-

4 I have given (‘Geolog. Obser- rocks of Ascension, and formed by
vations on Volcanic Islands,’ 1844, the solution of triturated see-sheila
p. 53) a curious imsvance of the

264 Lhe Descent of Man. Parr IL

living amongst corals or brightly-tinted sea-weeds, the bright
colours may serve as a protections But that many of the nucli-
branch 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 alge, 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 nudi-
branch molluses, 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 ad-
vantage 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 move brightly-tinted individuals
would succeed best and would increase in number; but this
would be @ 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 at-
tributed to sexual selection. These animals are often beanti-
fully 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

5 Dr. Morse has lately discussed ‘Proc. Boston Soc. of Nat. Hist,

this subject in his paper on the vol. xiv., April, 1871.
Adaptive Colcration of Mollusca,

Cuar. IX. Crustaceans. 265

Dr. McIntosh® cannot discover that these colours are of any
service. The sedentary annelids become duller-coloured, ac-
cording to M. Quatrefages,’ 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, antenne 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
doabt related to their widely different habits of life, and con-
sequently do not concern us. In various crustaceans, belonging to
distinct families, the anterior antenne 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 Miller 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 chele or pincers, which serve
to hold the female. Fritz Miiller 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 chelz; so that of the former, those which
were best able to find the female, and of the latter, those which

© See his beautiful monograph on ™ See M. Perrier, ‘l’Origine de
* British Annelids,’ part i. 1873, |’Homme d’aprés Darwin,’ ‘ Revue
p. 3. Scientifique,’ Feb. 1873, p. 866,

266

The Descent of Man.

Part II,

were best able to hold her, have left the greatest number of
progeny to inherit their respective advantages.®
In some of the lower crustaceans, the right anterior antenna

a

|

Fig. 4. Labidocera Darwinti

(from Lubbock).

a. Part of right anterior an-
tenna of male, forming a
prehensile organ.

b. Posterior pair of thoracic legs
of male.

¢. Ditto of female.

of the male differs greatly in structure
from the left, the latter resembling in
its simple tapering joints the antennz
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.? It serves, as J hear
from Sir J. Lubbock, to hold the
female, and for this same purpose one
of the two posterior legs (4) on the
same side of the body is converted
into a forceps. In another family the
inferior or posterior antenn® are
“curiously zigzagged” in the males
alone.

In the higher crustaceans the an-
terior legs are developed into chele
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 (Cuncer pagurus),
according to Mr. C. Spence Bate, is
five times as great as that of the fe-
male. In many species the chele 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 chelze

of the male often differ in structure (Ags. 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

for

® “Facts and Arguments
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 Pontoporeiu affine.

® See sir J. Lubbock in ‘ Annals

and Mag. of Nat. Hist.’ vol. xi.
1853, pl. i. and «.; and vol. xii.
(1853) pl. vii. See also Lubbock in
‘Transact. Ent. Soc.’ vol. iv. new
series, 1856-1858, p. 8. With re-
spect to the zig-zagged antenne
mentioned below, see Fritz Muller,
‘Facts and Arguments for Darwiu,’
1809, p. 40, fuot-note.

Cuar. 1X, Crustaceans. 267

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

Fig.5. Anterior part of body of Callianassa (from Milne-Fdwards), showing the un-
equal and differently-constructcd right and left-hand chela: of the male.

N.B—The artist by mistake has reversed the drawing, and made the left-hand chela
the largest.

Fig. 6. Fig. 7.

Fig. 6. Second leg of male Orchestia Tucuratinga (from Fritz Miiller).
Fig. 7. . Ditto of female.

often much larger in the male than in the female, is not known.
As | hear from Mr. Bate, the chele 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 (Palemon)
the right leg is actually longer than the whole body. The
grat size of the one leg with its chele may aid the male in
fighting with his rivals; but this will not account for their

10 See a paper by Mr. C. Spence 585. Iam greatly indebted to Mr.
Bate, with figures, in ‘Proc. Zoolog. Spence Bate for nearly all the above
Soc.” 1868, p. 363; and on the statements with respect to the chela
nomenclature of the genus, ibid. p. of the higher crustaceans.

268 The Descent of Man. Pant IL

inequality in the female on the opposite sides of of the body. In
Gelasimus, according to a statement quoted by Milne-Edwards,'
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 chele, 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 (Payurus) for weeks
together, carries about the shell inhabited by the female.’? The
sexes, however, of the common shore-crab (Curcinus menas), 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.

Fritz Miller states that certain species of Melita are distin-
guished 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 amphi-
pod (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 chele.% Aseither 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 Bracbyura, the male is
larger than the female; the parasitic genera, however, in which
the sexes follow different habits of life, and most of the Ento-
mostraca must be excepted. The chele of many crustaceans are

Mt ¢ Hist, Nat, des Crist.” tom. ji. of S. Devon.’
(837, p. 50. 18 Fritz Mither, ‘Facts and Argu:
12-Mr. C. Spence Bate, Brit. ments for Darwin,’ 1869, pp. 25-28
Assoc., Fourth Kevort m the Fauna

Cuap. 1X, Crustaceans. 269

weapons well adapted for fighting. Thus when a Devil-crab
(Portunus puber) was seen by a son of Mr. Bate fighting with a
Carcinus menas, 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 Miiller, they mutilated
and killed one another. Mr. Bate put a large male Carcinus

Fig. 8 Orchestia Darwinii (from Fritz Miiller), showing the differently-constructed
ch le of the two male forms.

meenas into a pan of water, inhabited by a female which was
naired with a smaller male; but the latter was soon dispossessed.

270 The Descent of Man. Part IL,

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, scon 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 (Biryas
datro), 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 con-
sidered : a trustworthy naturalist, Mr. Garduer," 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 the 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

14 ¢Tyayels in the Inter.or of 463, sn account of the habits of the
Brazil,’ 1846, p.111. Ihave given, Birgus,
in my ‘Journal oj Researches,’ p,

Cuan, 1X. Crustaceans. 271

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.”
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 shiclds or cell-like bodies, which exhibit beautiful
changing colours; these are absent in the females, and in
both sexes of one species.® It would, however, be extremely
rash to conclude that these curious organs serve to attract the
females. I am informed by Fritz Miiller, that in the female ofa
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 chele. 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. Fyrom 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 ofthe Vertebrata; and in all cases it is
eminently distinctive of characters which have been acquired
through sexual selection. Fritz Miiller™’ gives some striking
instances of this law; thus the male sand-hopper (Orchestia)
does not, until nearly full grown, acquire his large claspers,

18 Mr. Ch. Fraser, in ‘Proc. Zoo- 16 Claus, ‘ Die freilebenden Cope:
log. Soc.’ 1869, p. 3. Iam indebted poden,’ 1863, s, 35.
to Mr. Bate for Dr. Power's state- 17 ¢ Facts and Arguments, &-.,
ment. p. 79.

272 The Descent of Man. Pant Il.

which are very differently constructed from those of the female;
whilst young, his claspers resemble those of the female.

Class, Aruchni/u (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." 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 ¥
remarks that in certain genera the males can be specifically dis-
tinguished with eas, but the females with great difficulty. Iam
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, belore arriving at maturity.
In other cases the male alone appears to change colour. Thus
the male of the above bright-colonred Sparassus at first re-
sembles the female, and acquires his peculiar tints only when
nearby 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 ahout
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 TLheridion lineatum, it would
appear that these sexual characters of the males have not as yet
become well fixed. Canestrini draws the same conclusion from

+A History of the Spiders of ‘Caratteri sessuali secondarii degli
Great Britain,’ 1861-64. For the Arachnidi,’ in the ‘Atti della Soc
fcllowing facts, see pp. 77, 88, 102. Veneto-Trentina di Sc. Nat. Padova,
1 This author has recently pub- vol. i. Fase. 3, 1873.
lished a valuable essay on the

Guar. IX. Spiders. 273

the fact that the males of certain specics present two furms,
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,” 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.” #4
The Rev. 0. P. Cambridge™ 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, ie., 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 difticulty.”

Westring has made the interesting discovery that the males
of several species of Theridion™ have the power of making
a stridalating sound, whilst the females are mute. The ap-
paratus 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.** Froth the analogy of the Orthoptera and Homoptera,

20 Aug. Vinson (‘ Arandides des
Nes de la Reunion,’ pl. vi. figs. 1
and 2) gives a good instance of the
smal] size of the male, in Epeira
agra. 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,’
1868, July, p. 429); but I have
got seen the original accounts.

2) Mirby and Spence, ‘ Introduce

19

tion to Entomology,’ vol. i. 1818,
Pr 280.

22 «Proc. Zoolog. Soc.” 1871, p. 621.

23 Theridion (Asagena, Sund.)
serratipes, 4-punctatum et gutta-
tum; see Westring, in Kroyer,
*Naturhist. Tidskrift,’ vol. iv. 1842—
1843, p. 349; and vol. ii, 1846~
1849, p. 342. See, also, for other
species, ‘ Aranex Suecice,’ p. 184,

24 Dr. H. H. van Zouteveen, in
his Dutch translation of this work
(vol. i. p. 444), has collected severa
cases,

Parr E1

274 The Descent of Man.

to be described in the next chapter, we may fecl almost sure that
the stridulaticn 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,”*

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 lmbita, 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 pre-
hensile hooks which serve to secure the female. In some species
of Tulus 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 fersale in Lithobius, which is furnished with prehensile
appendages at the extremity of her body for holding the male.*

CHAPTER X.
SEconDARY SEXUAL CHARACTERS OF INSEOTS.

Diversified structures possessed bv 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 ;
pugnieity; colours—Neuroptera, sexual differences in colour—Hyme-
noptera, pugnacity and colours—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 antenne of the males of
many species. In Chloéon, one of the Ephemere, the male has
great pillared eyes, of whick the female is entirely destitute,
The ocelli are absent in the femates of certain insects, as in the

25 Hilgendorf, however, has lately ‘Hist. Nat. des Insectes: Apteres,’

called attention to an analogous

tum. iv. 1847, pp. 17, 19, 68.

structure in some of the higher ' Sir J. Lubbock, ‘ Transact.
rrustaceans, which seems adapted Linnean Soc.’ vol. xxv. 1866, p.
te produce sound; see ‘Zoological 484. With respect to the Mu-
Becurd,’ 1869, p. 603. tiliide tee Westwood, ‘ Modern

23 Walchenaer et P. Gervais,

Class, of Jasects,’ vol. if, p. 213,

nap. X, dnsects.

275

Mutillida; 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 af the abdomen, which ought perhaps to be ranked
as primary organs,” “it is astonishing,” as Mr. B. D. Walsh® has
remarked, “ how many different organs are worked in by nature
“ for the seemingly insignificant object of enabling the male to
“* prasp the female firmly.” The mandibles or jaws are some-
times used for this purpose; thus the male Corydulis cornutus (a
neuropterous insect in some degree allied to the Dragon-flies, &c.)
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.t. One of the
stag-beetles of North America (Lucanus eluphus) uses his jaws,
which are much larger than those of the female, for the same
purpose, but probably likewise for fighting. Im 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 ;”°
whilst the females use these organs for burrowing in sand-banks
and making their nests.

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 isa

2 These organs in the male often
differ in closely-allied species, and
afford excellent specific characters.
But their importance, from a func-
tional point of view, as Mr. R.
MacLachlan has remarked to me,
has probably been overrated. It
has been suggested, that slight dif-
ferences 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 in-
instance, Bronn, ‘ Geschichte der
Natur,’ B. ii. 1843, s. 164; and
Westwood, ‘Transact. Ent. Soe.’
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 Phryganide, which pre-
sent strongly-pronounced differences
of this kind, were confined together
by Dr. Aug. Meyer, they coupled,
and one pair produced fertile ova.

3 «The Practical Entomologist,
Philadelphia, vol. ii. May, 1867

, 88.

+ Mr. Walsh, ibid. p. 107.

5 Modern classification of In
sects,’ vol. ii. 1840, pp. 205, 206.
Mr. Walsh, who called my attention
to the double use of the jaws, savs
that he has repeatedly observed
this fact.

276 The Descent of Man. Parr 1,

much more unusual circumstance that the female of some water-
beetles (Dytiscus) have their elytra deeply grooved, and in
Acilius sulcutus 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.’ In the male of Crabrv
crbrarius Cfig. 9), it is the tibia
which is dilated into a broad
horny plate, with minute mem-
braneous dots, giving to it a sin-
gular appearance like that of a
riddle.’ In the male of Penthe
(a genus of beetles) a few of the
middle joints of the antenne are
dilated and furnished on the in-
ferior surface with cushions of hair,
exactly like those on the tarsi of
the Carabide, “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 em-
‘“ brace the neck of the female.”
Lastly, in the males of many in-
sects, 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 eharacter; or one pair, or all three
pairs are elongated, sometimes to an extravagant length.*

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 the left mandible
much enlarged; so that the mouth is greatly distorted. In
another Carabiduus beetle, Eurygnathus, we have the casc,

Fig. 9. Crabro cribrarius. Upper figure,
male; lower tigure, fewale.

® We have here a curious and
inexplicable case of dimorphism, tor
some of the females of four Euro-
pean species of Dytiscus, and of
certain species of Hydroporus, have
their elytra smooth; and no inter-
mediate gradations between the
sulcated or punctured, and the quite
smooth elytra have been observed.
See Dr. H. Schaum, as quoted in
the ‘ Zoologist,’ vol. v.-vi. 1847-48,
p- 1896. Also Kirby and Spence,

‘Introduction to Entomology,’ vol.
iii, 1826, p. 309.

7 Westwood, ‘Modern Class.’ vol.
ii, p. 193. The following state-
ment about Penthe, and others in
inverted commas, are taken from
Mr. Walsh, ‘Practical Entomolo-
gist,’ Philadejphia, vol. ii. p. 88.

8 Kirby and Spence, ‘Introduct,
&c., vol. iii. pp. 332-336.

® ‘Insecta Maderensia,’ 1854, p
20.

Cua, X, Lnsects. 277
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 extra-
ordinary is that certain male butterflies
have their fore-legs more or less atrophied,
with the tibie and tarsi reduced to mere ru-
dimentary knobs. The wings, also, in the two
sexes often differ in neuration,” and some-
times considerably in outline, as in the Ari-
coris epitus, Which was shewn to me in the
British Museum by Mr. A. Butler. . The males
of certain Sonth American butterflies have
tufts of hair on the margins of the wings,
and horny excrescences on the discs of the
posterior pair." Jn several British butter-
flies, 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 discus-
sion. The male is feebly luminous, as are the
larvee and even the eggs. It has been sup-
posed by some authors that the light serves to
Trighten away enemies, and by others to
guide the male to the female. At last, Mr.
Belt? appears to have solved the difficulty :
he finds that all the Lampyride 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 Lampyridee
closely, in order to be mistaken fur them, and
thus to escape destruction. He further be-
Neves that the luminous species profit by
being at once recognised as unpalatable.
It is probable that the same explanation may be extended to the

Fig. 10.
distortus (much en-
larged). Upper fig-

Taphroderes

ure, male; lower

figure, female.

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 Hymenop.’ 1837, pp. 39-
43) differ in neuration according to
Bex.

1H. W. Bates, in ‘Journal of
Proc. Linn. Soc.’ vel. vi. 1862, p.

74, Mr. Wonfor’s observations are
quoted in ‘ Popular Science Review,’
1868, p. 343.

12 «he Naturalist in Nicaragua,’
1874, pp. 316-320. On the phos-
phorescence of the eggs, see ‘ Annals
and Mag. of Nat. Hist.’ 1871,’ Nov.,
p. 372.

278 The Descent of Man. PaRT 43,

Elaters, both sexes of which are highly luminous. It is not
known why the wings of the fumale glow-worm have not beea
developed; but in her present state she closely resembles a
larva, and as larve are so largely preyed on by many animals,
we can understand why she has been rendered so much more
luminons and conspicuous than the male; and why the larve
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 (Zombyx mori), that in France they are
separated by a particular mode of weighing.’ 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 develop-
ment 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 in-
“ dividual moth is finer, so is the time required for its metamor-
“phosis 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.” Now as most insects are short-lived, and as
they are exposed to many dangers, it would manifestly be ad-
vantageous 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 re-
marked, 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 possessior of the females; and in
these cases, as with tle stag-beetle (Lucanus), the males are
larger than the females. There are, however, other beeties

‘3 Robinet, ‘Vere 4 Soie, 1348, vol. v. p, 486.
p. 207. 8 “Journal of Proe, Ent. See.
« ¢P-cneaet. Ent. Soc.’ 3rd veries, Feb. 4th, 1867, p. Ixxi.

Car. X, Thysanuva. 279

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 (Libellulide) are sometimes sensibly
larger, and never smaller, than the females;** 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.
Swith 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
municutum, and Anthophora acervorum, and amongst the Fossores,
the males of the Methoca ichnewmunides, 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 op-
position 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 organized
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?” 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

16 For this and other statements see p. 344,
on the size of the sexes, see Kirby 17 ¢Transact. Tiarean Soc,’ vob
and Spence, ibid. vol iii, p. 300; xxvi. 1868, p. 296.
en the duration of life in insects,

280 The Descent of Man. Part IL

“backward and forward like two playful lambs. Then the
female pretends to run away and the male runs after her with
@ 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 antenne; then for a bit they stand face to face,
“ play with their antenne, and seem to be all in all to one
“ another.”

Order, Diptera (Flics).—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, dis-
covered by Mr. Wallace’ 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 pal-
mated. 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 ccntral 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; for Prof. Westwood ” has several tines
seen this with the Tipula. The males of other Diptera ap-
parently try to win the females by their music: H. Miiller”
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 (Culicids, also seem to attract each other by hum-
ming; and Prof. Mayer has recently ascertained that the hairs
on the antenne 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 in-
sects, in accordance with their highly developed nervous system.”

‘8 <The Matay Archipelago,’ vol. 21 See Mr. B. T. Lowne’s interest-

ii, 1869, p. 313. ing work, ‘On the Anatomy of the
© «Moderz Classification of In- Blow-fly, Musca vomitoria,’ 1870, p.
sects,’ vol. ii. 1840, p. 526. 14, He remarks (p. 33) that, “the

2% Anwendung, &., ‘Verh. d.n. “captured flies utter a peculiar
V. Jahrg.’ xxix. p. 80. Mayer. ‘n “ plaintive note, and that this sound
american Naturalist,’ 1874, p. 230.“ causes other flies to disappear.”

Ouar. X, Hemiptera and Homoptera, 281

Order, Hemiptera (Field-Bugs).—Mr. J. W. Douglas, who has
particularly attended to the British species, has kindly given me
au 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, antenne 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 con-
spicuous colours may serve as a signal that they are unpalat-
able 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 Reduvide make a stridulating noise; and, in
the case of Pirates stridulus, this is said™ to be effected by the
movement of the neck within the pro-thoracic cavity. Accord-
ing to Westring, Reduvius personatus also stridulates. But I
have no reason to suppose that this is a sexual character, ex-
cepting 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 tropi-
cal forest must have been astonished at the din made by the
male Cicade. 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 ofa 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.™
The Cicadide usually sing during the day, whilst the Fulgoridss
appear to be night-songsters. The sound, according to Landois,”

22 Westwood, ‘Mocern Class. of also, on the Fulgoride, Kirby an{
Insects,’ vol. ii. p, 473. Spence, ‘ Introduct.’ vol. ii. p. 401.

23 These particulars aze taken 24 < Zeitschrift fiir wissenschaft
from Westwood’s ‘Modera Class. of Zoolog.’ B. xvii. 1867, s. 152--158.
‘nsects,’ vol. ii. 1840, p. 422. See,

282 The Descent of Man. Part IL

is produced by the vibration ot the lips of the spiracles, which
are set into motion by a current of air emitted from the trachesr ;
but this view has lately been disputed. Dr. Powell appears to
have proved” that it is produced by the vibration of a mem-
brane, 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, 7
“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 larve of Vic. pruinosa; and I several times noticed
“the females to alight near a male while he was uttering his
“ clanging notes.” Fritz Miller writes to me from S. Brazil
that he has often listened tv 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 isso 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 tbat 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 Achetide or crickets, the
Locustidx for which there is no equivalent English name, and the
Acridiide or grasshoppers. The stridulation produced by some

25 ¢Transact. New Zealand In- from 2 ‘Journal of the Doings of
stitute,’ vol. v. 1873, p. 285. Cicada septemdecim’ by Dr. Hart-
26 T am indebted to Mr. Walsh man.
for having stmt me this extract

Cua. X. Orthoptera. 283

of the Locustidee is so loud that it can be heard during the night
at the distance of a mile;*” 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” an
interesting case of selection by the female of a male. The males
of this species (Puchytylus mijratorius) 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.” In North America the Katy-did (Viuty-
phyllum concavum, one of the Locustidz) is described * as mount-
ing 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 Naty did-she-did
“the live-long night.” Mr.
Bates, in speaking of the Euro-
pean field-cricket (one of the
Achetidee), says, “ the male has
“ been observed to place him-
“self in the evening at the
“ entrance of his burrow, and
* stridulate until a female ap-
“‘ proaches, when the louder
“notes are succeeded by a
© more subdued tone, whilst
“the successful musician ca-
“ resses with his antenne the

“mate he has won.” Dr.
Scudder was able to excite one
of these insects to answer him,
by rubbing on a file with a
quill. In both sexes a re-
markable auditory apparatus

Fig.11 Gryllus campestris (from Landois)

Right-hand figure, under side of part of t
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.

has been discovered by Von Siebold, situated in the front legs.

27 L, Guilding, ‘Transact Linn.
Soc.’ vol. xv. p. 154.

28 I state this on the authority
of K6ppen, ‘ Ueber die Heuschrecken
in Suidrussland,’ 1866, p. 32, for I
have in vain endeavoured to procure
Korte’s work.

29 Gilbert White, ‘Nat. Hist. of
Selborne,’ vol. ii. 1825, p. 262.

30 Harris, ‘Insects of New Eng-
land,’ 1842, p. 128.

21 ¢The Naturalist on the Ama-

zons,’ vol. i. 1863, p. 252. Mr.
Bates gives a very interesting dis-
cussion on the gradations in the
musical apparatus of the three
families. See also Westwood,
‘Modern Class.’ vol. it, pp. 445
and 453.

32 ¢ Proc. Boston Soc. of Nat,
Hist.’ vol. xi. April, 1868.

33 ¢ Nouveau Manuel d’Anat.
Comp.’ (French translat.), tom. i
1850, p. 367.

284 The Descent of Man. Parr IL

In the three Families the sounds are differently produced. In
the males of the Achetidee both wing-covers have the same
apparatus; and this in the field-cricket (Gryllus campestris,
fig. 11) consists, as described by Landois,* of from 131 to 188
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 ner-
vure (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.*
T here give a drawing (fig. 12) of the teeth on
the under side of the nervure of another
Fig. 12. Teeth of Ner- species of Gryllus, viz, %. domesticus, - With

fe hun wuow, respect to the formation of these teeth, Dr.

Gruber has shewn* that they have been de-
veloped 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.

In the Locustide 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 («) 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 /hasgonura 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 vitinm, 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

34 «Zeitschrift fir wissenschaft, 36 ‘Ueber der Tonapparat der
Zoolog.’ B. xvii. 1867, s. 117. Locustiden, ein Beitrag zum Dar-

35 Westwood, ‘Modern Clais. of winismus,’ ‘Zeitsch. fiir wisseusch
Insects,’ vol. i. p. 440. Zoolog.’ B. xxii. 1872, p. 100.

Cnapr, X, Orthoptera, 285

“ot dome over the wing-covers, and which has probably the
“ effect of increasing the sound.” %7

Fig. 13, Chloroccelus Tanana (from Bates). a, b. Lubes vi opposite wing-covers.

We thus see that the musical apparatus is more differentiated
or specialised in the Locustide (which include, I believe, the
most powerful performers in the Order), than in the Achetide,
in which both wing-covers have the same structure and the
same function.2 Landois, however, detected in one of the
Locustidz, 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 Phasyonura viridissima, Hence we may
infer with confidence that the Locustide are descended from a
form, in which, as in the existing Achetide, both wing-covers
had serrated nervures on the under surface, and could be
indifferently used as the bow; but that in the Locustide the
two wing-covers gradually became differentiated and perfected,

37 Westwood, ‘Modern Class. of Insects,’ vol. i. p. 453.
38 Landois, ‘ Zeitsch. f. wiss. Zoolog.’ B. xvii. 1867, s. 121, 122.

286 The Descent of Man. Parr Lf.

on the principle of the division of labour, the one to act ex-
clusively 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 Achetide 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.® A grating sound thus occasionally and accidentally
made by the males, if it served them ever so little as a love-cali
to the females, might readily have been intensified through
sexual selection, by variations in the roughness of the nervures
having been continually preserved.

In the last and third Family, namely the Acridiide 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, 1)
is furnished with a lungitudinal row of minute, elegant, lancet-
shaped, elastic teeth, from 85 to 93 in number ;*° and these are
scraped across the sharp, projecting nervures on the wing-covers,
which are thus made to vibrate and resound. Harris 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 de-
“signed 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 re-
sounding board. In Pneu-
mora (fig. 15), a 8. African
genus belonging to the same family, we meet with a new

ON
oa)

Fig. 14. Hind-leg of Stenobothrus pratorum :
r, the stridulating ridge; lower figure, the
teeth forming the ridge, much magnihed
(from Landois).

39 Mr. Walsh also informs me ‘ wing-covers together.”

that he has noticed that the female
of the Platyphjllum concavum,
“when captured makes a feeble
“erating noise by shufiling her

4” Landois, ibid. s, 113.
1 ‘Insects of New England
1842, p. 133.

Cuap, X, Orthoptera. 287

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.” As the male is
furnished with wings (the female being wingless), it is re-
markable 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 heen
able to examine the inner surface of the thighs, which, judging

Fig. 15. Pneumora (from speciny ns in the British Museum). Upper figure, male;
Jower figure, female.

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
bcdy has been converted into a musical instrument, being

“2 Westwood, ‘ Modein Classification.’ vol, i. 0. 462.

288 The Descent of Man. Part IL

distended with air, like a great pellucid bladder, so as to
increase the resonance. Mr. Trimen informs me that at the
Cape of Good Hoye 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 Hphippiger 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 Locustide (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 Achetide, and on the femora of the
female Acridiide. 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 Acridiide, 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. 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 mul-
tifarious 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

4% Tandois has recently found in moptera; and this is a surprising
ecertuin Orthoptera rudimentary fact. See ‘ Zeitschr. fiir wissensch.
structures closely similar to the Zoolog.’ B xvii. Heft 3, 1871, p.
sound-producing organs in the Ho- 348 #

Cuae, X. Orthoptera. 28g

Homoptera, impresses the mind with the high importance of these
structures to the males, fur the sake of calling or alluring the
females. We nced 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,** 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 stridu-
“lating apparatus of the male Locustide.” 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 cumpestris) are confined together, they fight till one
kills the other; and the species of Mantis are described as
manceuvring 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.*® 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
1s 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 * 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 *’ 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 fem rutum (one of the Phasmidee) “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 is furnished with “a long membranous appendage,
“ which falls over the face like a veil;” but what its use may be,
is not known.

44 ¢ Transact. Ent. Soc.’ 3rd series, 47 The Gcanthus nivalis. Harris,

vol. ii. (‘Journal of Proceedings,’
p 117.)

45 Westwood, ‘Modern Class. of
Insects,’ vol. i. p. 427; for crickets,
vp. 445,

‘6 Mr. Ch. Horne, in ‘ Proc. Ent.
Sec’ May 3, 1869, p. xii.

20

‘Insects of New England,’ 1842, p.
124, The two sexes of &. pellucidus
of Europe differ, as I hear from
Victor Carus, in nearly the same
manner.

48 Platyblemnus: Westwood.
‘Me Jern Class.’ vol. i. p 447.

290 The Descent of Man. Part Ll.

Order, Neuroptera.—Little need here be said, except as ta
colour. In the Ephemeride the sexes often differ slightly in
their obscure tints; but it is not probable that the males are
thus rendered attractive to the females. The Libellulide, or
dragon-flies, are ornamented with splendid green, blue, yellow,
and vermilion metallic tints; and the sexes often differ. Thus,
as Prof. Westwood remarks,” the males of some of the
Agrionida, “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.”
In the extensive N. American genus of Heterina, the males alone
have a beautiful carmine spot at the base of each wing. In
Anaax junius the basal part of the abdomer 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 Libellulide, 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 * that the Agrionide, 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, ‘n
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 con-
spicuous 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 Libel/ula depressa this change of colour does not occur
until nearly a fortnight after the metamorphosis, when the sexes
are ready to pair.

4° B.D. Walsh, the ‘Pseudo-neu- indebted to this naturalist for the
roptera of Illinois, in ‘Proc. Ent. following facts on Hetzrina, Anax,
Soc. of Philadelphia,’ 1862, p. 361. and Gomphus.

3° ¢Medern Class.’ vo". ii. p. 37. *2 «Transact. Ent. Soc.” vol. i

{! Wa'sh, ibid. p. S8t. Tam 1836, p. lxxxi.

‘Onap, X. Lyme woptera. 291

Certain species ot Neurothemis present, according to Braucr,
«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 Agvrion, in which some individuals are of
an orange colour, and these are invariably females. This is

robably a case of reversion; for in the true Libellule, 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 Libellule in its sexual cha-
racters, 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.” The At, opus pulsutortus is said
to make a noise with its jaws, which is answered by other
individuals.”

Order, Hymenoptera.—That inimitable observer, M. Fabre,** 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 ” says that the males of one of the saw-flies (Tenthre-
dine) “ 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

53 See abstract in the ‘Zoological 56 See an interesting article,
Record ’ for 1867, p. 450. ‘The Writings of Fabre,’ in ‘ Nat.
54 Kirby and Spence, ‘Introduct. Hist. Review,’ April 1862, p. 122.
to Entomology,’ vol. ii. 1818, p. 35. 57 «Journal of Proc. of Entomolog

55 Houzeaa, ‘Les Facu.tés Men- Soc. Sept. 7th, 1863, p. 159
tales’ &c. Tom. i. p. 104.

292 The Descent of Man. Part II

each other after long intervals of time, and are deeply attached.
For instance, Pierre Huber, whose accuracy no one doubts,
separated some anis, 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
antenne. 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.

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 Ichneumouide, according to
Mr. Walsh,” the males are almost universally lighter-coloured
than the females. On the other hand, in the Tenthredinidsw the
males are generally darker than the females. In the Siricids
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
columbe the female is much brighter-coloured than the male.
I am informed by Mr. F. Smith, that the male ants of sevoral
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 Andrena 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. Miller, 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

s® P. Huber, ‘Recherches sur Jes Philadelphia,’ 1866, pp. 238-239.
Meurs des Fowrmis,’ 1810, pp. 150, 6° ¢ Anwendung der Darwinschen
165. Lehre auf Bienen.’ Verh. d. n.

s© «Prot Entomc.og. Soc. of Jahrg. xxix.

Cnap. X. Flymenoptera, 293

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 (Miiller, p. 42), the males of the
sevcral species differ much in appearance, whilst the females are
almost indistinguishable; in other genera the reverse occurs.
H. Miller 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.”

Mutilla Europeu makes a stridulating ‘noise ; and according to
Goureau ® 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 con-
centric 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. Itis 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. Muller (p. 80), the males of
some species make a peculiar singing noise whilst pursuing the
females.

81 M. Perrier in his article ‘la Sé-
lection sexuelle d’aprés Darwin’ (‘Re-
vue 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 fa-
cilitating 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 pruduce males; and will it be
pretended that such males would
aot 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 trom their male grand-
father? The acquirement of new
characters by the sterile worker-bees
is a much more difficult case, but I
have endeavoured to show in my
‘ Origin of Species,’ liow these sterile
beings are subjected to the power of
natural selection.

8 Quoted by Westwood, ‘Modera
Class. of Insects,’ vol. . p, 214.

The Descent of Man. Paar II.

294

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 tliat they have been gained through sexual
selection; but this is at least possible, for they may 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 expla-
nation of their obscurity may be that they gencrally inhabit
caves and other obscure stations. ,

Some Longicorns, especially certain Prionidee, offer an excey
tion 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,® which I saw in Mr. Bates’s col-
lection, are generally redder bnt 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 Prionida, in

63 Pyrodes pulcherrimus, in the family of Longicorns. Messrs.

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 (‘In-
troduct. to Entomology,’ vol. iii. p.
301) mention a Cantharis, Meloe,
Rhagium, and the Leptura testacea ;
the male of the latter being tes-
taceovs, with a black thorax, and
the temale of a dull red all over.
These two latter beetles belong to

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 ©. ruficollis) having a
rufous thorax.

Cuar. X. Coleoptera. 205

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.

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, &c., 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 re-
markable forms. (Figs. 16 to 20.) The females generally ex-
hibit 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 of Phanceus lancifer ; and only a little less
well developed in the females of some other species of this genus
and of Cepris. Iam 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.

stg 16. ‘Chalcosoma atlas. Upper figure, male (r duced); lower figure, female
: (nat. size).

296 The Descent of Man. Part IL

Fig 17. Copris isidis. (Lrft-hand figures, males.)

Fig. 18. Phaneeus faunus.

Fig. 19 1 ipclicus eantori.

Vig. 20. Onthophagus rangifer, enlarged

Onar. d. Coleoptera. 297

In almost all cases, the horns are remarkable from their ex-
cessive 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 found that in Phaneus curnifex the horus were thrice as
long in some males as in others. Mr. Bates, after examining
above a hundred males of Outhophagus rangifer (fig. 20), thought
that he had at last discovered a species in which the horns did
uot 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
caunot be of a definite nature. The horns do not show marks of
friction, as if used for any ordinary work. Some authors sup-
pose® 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 sufficieut 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 Copride, 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.

The males of Onitis furcifer (fig. 21), and of some other

64 © Proc. Entomolog. Soc. of °° Kirby and Spence, ‘Introduct,
Philadelphia,’ 1864, p. 228. Entomolog.’ vol. iii. p. 300.

298 The Descent of Man. Parr II.

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 fe-
males plainly exhibit a rudiment of a single
horn on the head (fig. 22, a), and of a crest
(2) on the thorax. That the slight thoracic
crest in the female is a rudiment of a pro-
jection proper to the male, though entirely
Fig 21. Onitis furcifer, absent in the male of this particular species,
male viewed from be- i 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 (@) on the head of the female Onitis

Fig. 22, Left-hand figure, male of Onitis furcifer, viewed laterally, Right-hand
hgure, female. u. Rudiment of cephalic horn. b. Trace of thoracic horn or crest.

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 Phanzeus (fig. 18).

‘Lhe old belief that rudiments have been created to complete
the scheme of nature is here so far from holding good, that we
nave 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.

Cuar. X, Coleoptera. 299

The cases hitherto given refer to the Lamellicorns, but the
males of some few other beetles, belonging to two widely distinct
groups, namely, the Curculionide and Staphylinide, are fur-
nished with horns—in the former on the lower surface of the
body," in the latter ou the upper surface of the head and thorax.
In the Staphylinide, 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 Staphylinide, Professor Westwood

Fig. 23. Bledius taurus, magnified. Left-hand figure, male; right-hand figure female.

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 qnite rudimental; and others, in which the
“thoracic horn is much shorter, whilst the protuberances on
“the head are long.”®’ 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® 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 borine.
“ 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

86 Kirby and Spence, ‘Introduct. gonium in an intermediate condi-
Entomolog.’ vol. iii. p. 329. tion, so that the dimorphism is not

87 «Modern Classification of In- strict. :
sects,’ vol. i. p. 172: Siagonium, 88 «The Malay Archipelago,’ vol.
p- 172. In the British Museum I ii 1869, p.276. Riley, Sixth ‘ Revort
noticed one male specimen of Sia- on insects of Missouri,’ 1874, p. 115.

300 The Descent of Man. Past I]

engage in fierce conflicts. When Mr. A. H. Davis® 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 avimals.
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 Lucanide, as well as of the
above-mentioned Leptorhynchus, are larger and more powerful
insects than the females. The two sexes of Lethrus cepha'otes
(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 con-
tinually pushing him on from behind; and the battle lasts until
the aggressor is killed or runs away.” The two sexes of another
Lamellicorn beetle, the <Ateuchus cicatricosus, live in pairs, and
seem much attached to each other; the male excites the female
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.

The great mandibles of the male Lucanide 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 Staphylinide. A perfect series can be formed from the
best-provided to the worst-provided or degenerate males, Al-
though 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 con-
spicuous 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
8. Chile—a splendid beetle belonging to the same family—has

69 ‘Entomological Magazine,” vol. 7 Quoted from Fischer, in ‘ Dict.
*, 1833,-p. 82. See also on thc Class. d’Hist. Nat.’ tom. x. p. 324.
conflicts of this species, Kirby ana 71 ¢ Ann. Soc, Entomolog. France,’

Spence, ibid. vol. iii. p. 314; and 1866, as quoted in ‘Journal of
Westwood, ibid. vo. i. p. 187. Tri vel,’ by A. Murray, 1868, p. 135,

Cuap. X. . Coleoptera. 301

enormously developed mandibles (fig. 24); he is bold and pug-
nacious; 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
show mutual affection; many have
the power of stridulating when excited ;
many are furnished with the most ex- .
traordinary horns, apparently for the
sake of ornament; and some, which
are diurnal in their habits, are gor-
geously coloured. Lastly, several of
the largest beetles in the world belong
to this family, which was placed by
Linneus and Fabricius at the head of
the Order.”

Stridulating organs —Beetles belong-
ing 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,” but itis 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

. a a Fig. 24. Chiasognathus grantii,
Typhceus, minute, bristly or scale-like reduced, Tippee deve, vanley

prominences, with which the whole wer figure, female.
surrounding surface is covered in approximately parallel
lines, could be traced passing into the ribs of the rasp. The

72 Westwood, ‘Modern Class.’ Curculionida,’ ‘ Annals and Mag. of
vol i. p. 184. Nat. Hist.’ vol. vi. 1860, p. 14.
73 W-llaston, ‘On certain Musical

302 The Descent of Man. Panr Il,

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 [andois).

r The two rasps.
the rasp highly magnified.

left-hand figure, part of

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” 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 Crioceridz,
and in Clylhra 4-punctata (one of the Chrysomelids), and in some
Tenebrionids, &c.,7° 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.” In certain Curculionids and Carabide,” the parts

74 Landois, ‘Zeitschrift fiir wiss.
Zoolog.’ B. xvii. 1867, s. 127.

7 I am greatly indebted to Mr.
G. RB. 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 informa-
tion and specimens. I may add
that my son, Mr. F. Darwin, finds
that Dermestes murinus stridulates,
but he searched in vain for the
apvaratus. Scolytus has lately

been described by Dr. Chapman as
a stridulator, in the ‘Entomolo-
gist’s Monthly Magazine,’ vol. vi. p.
130.

76 Schiddte, translated in ‘ Annals
and Mag. of Nat. Hist.” vol. xx,
1867, p. 37.

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 Carabide I have
examined Llaphrus uliginosus and
Blethisa multipunctata, sent to me
by Mr. Crotch. In Blethisa the
transverse ridges on the furrowed
border of the abdominal segment do

Cuap. X. Coleoptera. 303

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 Dytiscide
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 abdonien being scraped against
the rasps. In a great number of long-horned beetles (Longi-
cornia) the organs are situated quite otherwise, the rasp being
on the meso-thorax, which is rubbed against the pro-thorax;
Landois counted 233 very fine ribs on the rasp of Cerambyx
heros,

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 Zrox 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 Typhceus a
narrow ridge runs obliquely across (r, fig. 26)
the coxa of each hind-leg (having in G. ster-
corarius 84 ribs), which is scraped by a
specially projecting part of one of the ab-
dominal 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 mar-
gin; but in some other Coprini the rasp is
seated, according to Leconte,” on the dorsal
surface of the abdomen. In Oryctes it is J
seated on the pro-pygidium ; and, according to 8
the same entomologist, in some other Dynastini, Fig. 26. Hind-leg of
on the under surface of the elytra. Lastly, — Geotrupes stercora-
Westring states that in Omaloplia brunnea the | Ws" ise
rasp is placed on the pro-sternum, and the "Femur. “t. Tibia
scraper on the meta-sternum, the parts thus ’ 7"
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

not, as far as I could judge, come of Illinois, for having sent me ex-
into play in scraping the rasps on tracts trom Leconte’s ‘ Introduction
the elytra. to Entomology,’ pp. 101, 143.

78 | am indebted to Mr. Walsh,

304 The Descent of Man. Pau IL

stridulating organs are wonderfully diversifiud 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 Huchirus longimanus (a
Lamellicorn, with the anterior legs wonderfully elongated in the
male) “ makes, whilst moving, a low hissing sound by the pro-
“ trusion 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, 1
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 ex-
amined, the rasp was considerably larger in the male than in
the female; but not so with succeeding specimens. In Geo-
trupes 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 Jesser 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

Cnap, X. Coleoptera. 305
to the females in both the lots. Mr. F. Smith has kept alive
numerous specimens of Monoynchus pseudacort (Curculionids),
and is convinced that both sexes stridulate, and apparently in
en equal degree.

Nevertheless, the power of stridulating is certainly a sexval
character in some few Coleoptera. Mr. Crotch discovered that
the males alone of two species of Heliopathes (Tenebrionida)
possess stridulating organs. I examined tive males of H. gibbus,
and in all these there was a well-developed rasp, partially
livided into two, on the dorsal surface of the terminal abdominal
segment; whilst in the same number of females there was not
uven 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 U. 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
differcr.ce 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
1s 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
le a doubt that the males stridulate in order to call or to
excite the females; but with most beetles the stridulation

21

The Descent of Man. Part 1

306

apparently serves both sexes as a mutual call. Beetles stridu-
late 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 Atenchus stridulates to
encourage the female in her work, and from distress when she
is removed.” 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 stridu-
lation serves as a sexual call is supported by the fact that death-
ticks (Avobium 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,” 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.

79 M. P. de la Brulerie, as quoted Landois, ‘ Zeitschrift ftir wissen.
in ‘Journal of Travel,’ A. Murray, Zoolog.’ B. xvii. s. 131. Oliver

vol. i, 1868, p. 135.

*0 According to Mr. Doubleday,
“the noise is produced by the in-
“ sect raising itself on its legs as
“high as it can, and then striking
“its thorax five or six times, in
“ rapid succession, agaitst the sub-
“ stance upon which it is sitting.”
For references on this sasyect see

says (as quoted by Kirby and
Spence, ‘Introduct.’ vol. ii. p. 395)
that the female of Pimetia striata
produces a rather loud sound by
striking her abdomen against any
hard substance, “and that the male,
“ obedient to this call, soon attenda
“her, and they pair.”

Cuap. XL. Butterflies and Moths.

w
e)
“a

CHAPTER Xf.

InsEcTs, continued.—OrpER LEPIDOPTERA.
(BUTTERFLIES AND MOTIIS.)

surtship of butterflies—Battles—Ticking noise—Colours common to
both sexes, or more brilliant in the males—kExamples—Not due tv 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
cemarks on the secondary sexual characters of insects—Birds and insects
ompared.

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 pirouct-
ting 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 bim, 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 aro
pugnacious, and an Emperor butterfly’ 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.”

1 Apatura Iris: ‘The Entomolo- Naturalist,’ 1868, p. 183.
gist’s Weekly Intelligence,’ 1859, p. 2 See my ‘ Journal of Researches,’

For the Bornean Butterflies, 1845, p. 33. Mr. Doubleday has
«ee “. Collingwoed, ‘Rambles of a detected (‘ Proc. Ent. Soc.’ March

308

The Descent of Man.

Part IL,

Some moths also produce sounds; for instance, the males of
Thecuphora fovea, On two occasions Mr. F. Buchanan White§
heard a sharp quick noise made by the male of fylophila
prasinana, and which he believes to be produced, as in Cicada,
by an elastic membrane, furnished with a muscle. He quotes,
also, Guenée, 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 vreistion with the sexual functions. I have not alluded
to the wei-known noise made by the Death’s Head Sphinx, for
it is generally heard soon after the moth has emerged from
its cocoon.

Girard has always observed that the musky odour, which is
emitted by two species of Sphinx moths, is peculiar to the males ;*
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, cr that one sex may be at-
tractive 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 ly given.

With our beautiful English butterflies, the admiral, peacock,
and painted lady (Vanesse), as well as many others, the sexes
are alike. This is also the case with the magnificent Heliconida,
and most of the Danaids in the tropics. But in certain other
tropical groups, and in some of our English butterflies, as the
purple emperor, orange-tip, &e. (Apaturu Iris and Anthocharis
curdamines), the sexes differ either greatly or slightly in colour.
No language suffices to describe the splendour of the males of

3rd, 1845, ¢ 229) a peculiar rem-
branous sac at the base of the
front wings, which is probably con-
nected with the production of tae
sound. For the case of T..ecophora,
see ‘Zoological Record,’ 1869, p
401. For Myr. Buchanan White’s

observations, ‘The Scottish Natural-
ist,’ July 1872, p. 214.

3 «The Scottish Naturalist,’ July
1872, p. 213.

+ “Zoological Fecord,’ 1869, p
347,

Swap. XL Butterflies and Moths. 309

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.> 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 tue
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-Lorm 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 Aineas 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

5 See also Mr. Bates’s paper in the same subject, in regard te
Proc. Ent. Soc. of Philadelphia,’ Diadema, in ‘ Transact. Entomolog,
1865, p. 206. Also Mr. Wallace on Soc. of London,’ 1869, p. 278.

310 The Descent of Man. Parr IL

others the males are either a little brighter, or very much more
superb than the females. The genus Junonia, allied to our
Vanesse, 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. enone, the male is
rather more bright-coloured than the female, and in a few (for
instauce 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
Thecle, in which both sexes are nearly alike and wonderfully
splendid; in another species the male is coloured in a similarly
gorgeous mauner, whilst the whole upper surface of the
female is of a dull uniform brown. Our common little English
blue butterflies of the genus Lycena, illustrate the various dif-
ferences in colour between the sexes, almost as well, though not
in so striking a manner, as the above exotic genera. In Lycena
agestis both sexes have wings of a brown colour, bordered with
small ocellated orange spots, and are thus alike. In L. egou
the wings of the male are of a fine blue, bordered with black ;
whilst those of the female are brown, with a similar border,
closely resembling the wings of ZL. 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
wore alike.

I have given the foregoing details in order to show, 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

Cuapr. XI, Butterflies and Moths. 311

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 con-
clude 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 *® has shewn 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 bril-
liantly-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. Réssler, I believe, first noticed the similarity of the
closed wings of certain Vanessee 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? of a common Indian and Sumatran butterfly (Kallima),
which disappears like magic when it settles on a bush; for it
hides its head and antennz between its closed wings, which,
in form, colour and veining, cannot be distinguished from a
withered Jeaf with its footstalk. In some other cases the lower

6 <The Naturalist on the Ama- 1867, p. 10. A woodeut of the
tens,’ vol. i, 1863, p. 19. Kallima is given by Mr. Wallace in

7 See the interesting article in ‘ardwicke’s Science Gossip,’ Sept.
tho ‘Westminster Review,’ July 1867, p. 196.

312 The Descent of Man. Parr 11.

surfaces of tLe wings are brilliantly coloured, and yet are
protective; thus in /ecla 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.®

Although the obscure tints both of the upper and under
sides of many butterflies no doulit 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
Vanesze, 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 ave alike; but in the common brim-
stone butterfly (Gonepteryx rhumni), 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,’ that the female of one ot
the Lycsenz 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 ot
the upper surface of his wings, rests with them closed; and this
shews that the blue colour cannot be in any way protective.
Nevertheless, it is probable that conspicuous colours are in-
directly 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 ygenutiéa which have
departed from the usual type of the genus. In the Axth. sera

8 Mr. G. Fraser, in ‘ Nature,’ ® «Einfluss der Isclirung auf i1¢
April 1871, p. 489. Artbildung,’ 1872, p. 58

Suar. XI, Butterflies and Moths. 333

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 gluucippe, the oringe-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 fiower-head of the wild parsley, on which the
butterfly often rests at night.” 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 confiued 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 Bombycide and Noctuide," 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
(Tripheena) 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 oi
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 in
stance, Mr. Weir turned into his aviary a vigorous specimen of
Triphena 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.” We are thus reminded of a statement made

10 See the interesting observations Science Gossip,’ Sept. 1867, p. 193.
oy Mr. T. W. Wood, ‘ The Student,’ 12 See also, on this subject, Mr
fept. 1868, p. 81. Weir’s paper in ‘ Transact. Ent. Soc.

Me, Wallace in ‘Hardwicke’s 1869, p, 23.

314 The Descent of Man. Part IL

by Mr. Wallace,” namely, that in the Brazilian forests and
Malayan islands, many common and bighly-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 in-
“ directly beneficial.”

Displuy.—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 Zygenide, several Sphingide, Uraniide.
some Arctiidae and Saturniide, 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."

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 raiso
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. In the Eng-
lish fritillaries (Argynnis) the lower surface alone is orna-
mented 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

18 ¢ Westminster Review,’ July
1867, p. 16.

14 For instance, Lithosia; but
Prof. Westwood (‘Modera Class. of
Insects,’ vol. ii. p. 390) seems sur-
prised 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.

5 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
Papilionide of the Malayan Region,”
in ‘Transact. Linn. Soc.’ vol. wx
part i. 1865.

Cuar. XI. Butterflies and Moths. 315

useful character for detecting the affinities of the various
species. Fritz Miiller informs me that three species of Castnia
are found near his house in §. 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 spccies has
black hind-wings, beautifully spotted with red and white, and
these are fully expanded and displayed whenever the butterfly
tests. Other such cases could be added.

If we now turn to the enormous group of moths, which, as
I lear 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.® Mr.
Trimen informs me that in Guenée’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 fure-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
Geomctree? and quadrifid Noctuz 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 con-
“ siderable 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 Saturniide 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™ 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 diurnai than of
‘6 nocturnal Lepidoptera.” ;

1@ See Mr. Wormald on this the Geometre) in ‘Transact. Ent.
tooth: ‘Proc. Ent. Soc.’ March 2nd, Soc.’ new series, vol. v. pl. xv. and
1865. xvi.

17 See also an account of the S. 18 ¢Pyoc, Ent. Soc. of London,’
Smerican genus Erateina (one of July 6, 1808, p. xxvia.

316 The Descent of Man. Part IL

It is a singular fact that no British moths which are bril-
liantly 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 Sutuinsa Jv, is described as having its
fure-wings deep yellow, curiously marked with purplish-red
spots; whilst the wings of the female are purple-brown, marked
with grey lines.” 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,” 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 exclamation /s
offers a good instance. In the Ghost Moth (Hepialus humul?)
the difference is more strongly marked; the males being white,
and the females yellow with darker markings.” 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 suke of protection. We
have seen that their colours and elegant patterns are arranged

and exhibited as if for display.
the females prefer or are most

19 Harris, ‘Treatise,’ &c., edited
by Flint, 1862, p. 393.

20 For instance, I observe in my
son’s cabinet that the males are
darker than the females in the
Lasiocampa quercus, Udonestis pota-
toria, Hypogymn « disp wr, Dasychira
pudibunda, and Cycni« 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 ex-
plained. The white female of the
Cycnia resembles the very common
Spilosoma menthrasti, both sexes of
which are white; and Mr. Stainton
observed that tkis latter moth was
rejected with utter disgust by a
whole crool of young turkeys,

Hence I am led to believe that
excited by the more brilliant

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 de-
ceptive colour would thus be highly
beneficial.

21 Jt is remarkable, that in the
Shetland Islands the male of this
moth, instead of differing widely
from the female, frequently re-
sembles her closely in colour (sce
Mr. MacLachlan, ‘Transact. Ent.
Soc.’ vol. ii. 1666, p. 459). Mr.
G. Fraser suggests (‘ Nature,’ April
1871, p. 489) that at the season of
the year when the ghost-moth ap-
pears in these northern islands, the
whiteness of the males would not
be needed to render them visible te
the females in the twilight night.

Cuap. XL Butterfiies and Moths. 317

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 attach-
ment for each other, and that ants recognise their tellows 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 Miiller informs me that several
kinds of butterflies in S. Brazil shew an unmistakable prefer-
ence 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” in speaking of
the difficulty in coliecting 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 hand, 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 ot
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 ot
many Lepidoptera, at least in the imago state, greatly exceed
the females in number.

Some facts, however, are opposed to the belief that femaia

2 ¢ Rambles of a Naturalist in the Chinese Seas,’ 1868, p. 182.

318 The Descent of Man. Part IT.

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 Bombycide, 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 Bumbyx 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 Bombycida,
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, showing 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.

Caap, XI. Butterflies and Moths, 319

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 Hip-
parchia 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 Colius 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 but-
terflies, the females take the more active part in the final mar-
riage 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 becn 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.”

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 Lepi-
doptera could be named. One good instance will suffice. Mr.
Bates shewed me a whole series of specimens of Papilio sesostris
and P. children; 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. childrene : and it likewise varies a little in the size of

23 ‘Nature,’ April 27th, 1871, p. whilst pairing. See also Mr. G.
508. Mr. Meidola quotes Donzel, Fraser, in ‘Nature,’ April 20th,
in ‘Soc. Ent. de France,’ 1837, p. 1871, p. 489, on the sexual differ-
77, on the flight of butterflies ences of several British butterflies.

320 Pant Ii.

The Descent of Man.

the green patch on the fore-wings, and in the occasional ap-
pearance 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 Aineas group possess
this crimson stripe. Hence between the brightest specimens
of P. sesostris and the dullest of P. childrenc, there was but a
small interval; and it was evident that as far as mere varia-
bility is concerned, there would be no difficulty in permanently
increasing the beauty of either species by means of selectiou.
The variability is here almost confined to the male sex; but
Mr. Wallace and Mr. Bates have shewn™ 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 und absent in the other, nor do they
ever differ much in the two sexes. This fact is at present
inexplicable; but if it should hereafter be found that the for-
mation 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

24 Wallace on the Papilionida of
the Malayan Region, in ‘ Transact.
Linn. Soc.’ voi. xxv. 1865, pp. 8,
36. A striking case of a rare
variety, strictly intermediate be-
tween two other well-marked female
varieties, is given by Mr. Wallace.
See also Mr. Bates, in ‘Proc. En-

tomolog. Soc.’ Nov. 19th, 1866, p.
xl.

25 Mr. Bates was so kind as to
lay this subject before the Entomo-
logical Society, and I have recaived
answers to this effect from several
entomologists.

Cuap. XI. Butterflies and Moths. 327

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 differences in colour between
the sexes may not be accounted for by other means besides
sexual selection. Thus the males and females of the sama
species of butterfly are in several cases. known” 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,” as in the adult state they are
exposed to different conditions during a very short period; and
the larvee 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 ap-
proximately 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 Ido 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 cquai

26 H. W. Bates, ‘The Naturalist 27 On this whole subject see ‘The
on the Amazons,’ vol. ii. 1863. p. Variation of Animals and Plants
228. A. R. Wallace, in ‘Transact. under Domestication,’ 1868, vol. ib
nian. Soc.’ vol. xxv. 1865, p. 10, chap. xxiii.

22

322 Lhe Descent of Man. Part hi.

inheritance by both sexes has prevailed, the selection of bright-
coloured ma_es 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 simultancously,
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.

Tn 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 chanved
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 protec-
tion, though it is probable that the male acquired his bright
colours as a sexual attraction. The female of Anthocharis cur-
damines 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-coleured
I.epidoptera it is the male whick has been chiefly modifiud
through sexual selection; the amount of difference Letweeu

Ouar. XI. Butterflies and Moths. 323

the sexes mostly depending on the form of inheritance which
has prevajled. Inheritance is governed by so many unknown
laws or conditions, that it seems to us to act in a capricions
manner ;* 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 suc-
cessive steps in the process of variation are necessarily trans-
mitted 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 specics are in a fixed condition.
Mimicry.—This principle was first made clear in an admirable
paper by Mr. Bates, who thus threw a flood of light on many
obscure problems, It had previously been observed that certain
butterflics in S. America belonging to quite distinct families,
resembled the Heliconids so closely in every stripe and shade of
colour, that they could not be distinguished save by an ex-
perienced entomologist. As the Heliconide 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 Heliconide the imitated.
Mr. Bates further observed that the imitating species are com-
paratively rare, whilst the imitated abound, and that the two
sets live mingled together. From the fact of ‘the Heliconids
being conspicuous and beautiful insects, yet so numerous in
individuals and species, he concluded that they must be pro-
tected from the attacks of enemies by some secretion or odour;
and this conclusion has now been amply confirmed,® 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

% ‘The Variation of Animals and xxiii. 1862, p. 495.
Plants under Domestication,’ vol. ii. 20 ¢ Proc. Ent. Soc.’ Dee. 31d
snap. xii. p. 17. 1866, p. xlv.

28 ¢ Transact. Jinn. Soc.’ vol.

324 The Descent of Man. Parr JL,

in this chapter. Sincc 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.”

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 modi-
fied 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 heen 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
forra 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 illus-

tration of these remarks in a

31 Wallace, ‘Transact. Linn. Soc.’
vol. xxv. 1865, p. 1; 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 Noxi-
ous Insects of Missouri,’ 1871, pp

statement by Mr. Belt;*? that

163-168. This latter essay is valu-
able, as Mi. Riley here discusses all
the objections which have been
raised against Mr. Bates’ theory.

%2 <The Naturalist in Nicaragua
1874, p. 385.

Cuap. XI, Butterflies and Moths. 325

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
“ parred and spotted with black, red aud 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
* fomales, 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 cater-
pillars 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 Jarve 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 ou the open llanos of South America; 1t 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 applicd 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

326 The Descent of Man.

Parr Il

Mr. Wallace remarks, * distastefulness alone would be insufficient
“ to protect a caterpillar unless some outward sign indicated te
“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-re-
cogrised individuals.

This hypothesis appears at first sight very bold, but when it
was brought before the Entomological Society ** 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.* Three conspicuous kinds of cater-
pillars 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 appear-
ance, either in imitation of surrounding objects, or from the
direct action of climate, &c., 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 hemarks on Insects——Looking back

33 «Proc. Entomolog. Soc.’ Dec.
3yd, 1866, p. xlv., and March ¢th,
1867, p. xxx.

34 See Mr. J. Jenner Weir’s
paper on Insects and Insectivorous
Birds, in ‘ Transact. Ent. Soc.’ 1869,
bp. 21, also Mr. Butler’s paper,
bid. p. 27, Mr. Riley has given

analogous facts in the ‘Third An-
nual 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,

Oaap, XT, Summary on Insects. 327

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 ix in only a few cases that the males have
been rendered larger and stronger than the females. On the
zontrary, they are usually smaller, so that they may be develored
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 Orthop-
tera, 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
gharming or exciting them in rivalry with other males. No
one who admits the agency of selection of any kind, will, after
reading the ahove discussion, dispute that these musical instru-
ments 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 Lamel-
licorn, 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

328 The Descent of Man. Part Ii

horns, magnified +o 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 heen
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
antil some little time after their emergence from the pupal
state, and when they are ready to breed.

Cuap, XT. Summary on Insects. 329

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 con-
trivances possessed by the males, such as great jaws, adhesive
cushions, spines, elongated legs, &c., for seizing the female; for
these contrivances shew 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
sclection 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 se-
lection, 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 difficuit in
those Orders, such as Orthoptera, Hymenoptera, and Coleop-
tera, 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
sumetimes 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 stridu-
lating 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 mules

320 The Descent of Man. Part Ii.

the green patch on the fore-wings, and in the occasional ap-
pearance 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 Auneas group possess
this crimson stripe. Hence between the brightest specimens
of P. sesostris and the dullest of P. children, there was but a
small interval; and it was evident that as far as mere varia-
bility 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™ 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 und absent in the other, nor do they
ever differ much in the two sexes. This fact is at present
inexplicable; but if it should hereafter be found that the for-
mation 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

24 Wallace on the Papilionida of tomolog. Soc.’ Nov. 19th, 1866, p.
the Malayan Region, in ‘Transact. xl.

Linn. Soc.’ vol. xxv. 1865, pp. 8,
36. A striking case of a rare
variety, strictly intermediate be-
tween two other well-marked female
varieties, is given by Mr. Wallace.
See also Mr. Bates, in ‘ Proc. En-

25 Mr. Bates was so kind as to
lay this subject before the Entomo-
logical Society, and 1 have recived
answers to this effect from several
entomologists.

Cuap. XI. Butterflies and Moths. 321

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 differences in colour between
the sexes may not be accounted for by other means besides
sexual selection. Thus the males and females of the sama
species of butterfly are in several cases. known” 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,” as in the adult state they are
exposed to different conditions during a very short period; and
the larve 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 ap-
proximately 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 Ido 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 cquai

26 H. W. Bates, ‘The Naturalist 27 On this whole subject sce ‘The
on the Amazons,’ vol. ii. 1863. p. Variation of Animals and Plants
228. A. R. Wallace, in ‘Transact. under Domestication,’ 1868, vol. ib
nian. Soc.’ vol, xxv. 1865, p. 10. chap. xxiii.

22

322 Lhe Descent of Man. Part hi.

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. 1f both processes were carried on simultancously,
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 cf
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 chanzed
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 protec-
tion, though it is probable that the male acquired his bright
colours as a sexual attraction. The female of Anthocharis cur-
daméines 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-colcured
T.epidoptera it is the male which has been chiefly modificd
through sexual selection; the amount of diffiaence between

Cuap. XI. Butterflies and Moths. 323

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 capricions
manner ;* 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 suc-
cessive steps in the process of variation are necessarily trans-
mitted 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 specics are in a fixed condition.
Mimicry.—This principle was first made clear in an admirable
paper by Mr. Bates,” 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 Heliconidx so closely in every stripe and shade of
colour, that they could not be distinguished save by an ex-
perienced entomologist. As the Heliconide 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 Heliconidz the imitated.
Mr. Bates further observed that the imitating species are com-
paratively rare, whilst the imitated abound, and that the two
sets live mingled together. From the fact of ‘the Heliconide
being conspicuous and beautiful insects, yet so numerous in
individuals and species, he concluded that they must be pro-
tected from the attacks of enemies by some secretion or odour ;
and this conclusion has now been amply confirmed,” 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

% ¢The Variation of Animals and xxiii. 1862, p. 495.
Plants under Domestication,’ vol. ii. 30 ¢Pyoc. Ent. Soc.’? Dec. 31d
snap, xii. p. 17. 1866, p. xlv.

29 ¢ Transact. Jinn. Soc.’ vol.

324 The Descent of Man. Pagt IL

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.”

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 modi-
fied 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 heen 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.” Jt 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 illus-
tration of these remarks in a statement by Mr. Belt; that

31 Wallace, ‘Transact. Linn. Soc.’ 163-168. This latter essay is valu-
vol. xxv. 1865, p. 1; also ‘Transact. able, as Mx. Riley here discusses all
Ent. Soc.’ vol. iv. (3rd series), 1867, the objections which have been
p. 301, Trimen, ‘Linn. Transact.’ raised against Mr. Bates’ theory.
vol. xxvi. 1869, p. 497. Riley, 32 ¢The Naturalist in Nicaragua
‘Third Annual Report on the Noxi- 1874, p. 385.
ous Insects of Missouri,’ 1871, pp

JHap. XI, Butierfiies aud Moths. 325

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 aud 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 Catrpillars,— Whilst reflecting on the
beauty of many butterflies, it occurred to me that some cater-
pillars 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 larve 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 ou the open Ilanos 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
“ teed, 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 quité 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 devourcd. Hence. as

326 Parr ll

The Descent of Man.

Mr. Wallace remarks, “ distastefulness alone would be insufficient
“ to protect a caterpillar unless some outward sign indicated ic
“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-re-
cogrised individuals.

This hypothesis appears at first sight very bold, but when it
was brought before the Entomological Society * 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.* Three conspicuous kinds of cater-
pillars 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 appear-
ance, either in imitation of surrounding objects, or from the
direct action of climate, &c., 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 ant Concluding hemarks on Insects—Looking back

38 (Proc, Entomolog. Soc.’ Dec,
8rd, 1866, p. xlv., and March 4th,
1867, p. lxxx.

34 See Mr. J. Jenner Weir’s
paper on Insects and Insectivorous
Birds, in ‘ Transact. Ent. Soc.’ 1869,
vb. 21, also Mr. Butler’s paper,
bid. p. 27. Mr. Riley has given

analogous facts in the ‘Third An-
nual 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
at9,

Onap, XT, Summary on Insects. 327

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 ix in only a few cases that the males have
been rendered larger and stronger than the females. On the
2ontrary, they are usnally 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 Orthop-
tera, 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 dpparently for
sharming or exciting them in rivalry with other males. No
one who admits the agency of selection of any kind, will, after
reading the ahove discussion, dispute that these musical instru-
ments 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 Lamel-
licorn, 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

328 The Descent of Man. Parr Ii

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 aro
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 heen
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
antil some little time after their emergence from the pupal
state, and when they are ready to breed.

Guar. XI: Summary on Insects. 329

Sexuai 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
tuat 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 con-
trivances possessed by the males, such as great jaws, adhesive
cushions, spines, elongated legs, &c., for seizing the female; for
these contrivances shew 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
sclection 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 tlie
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 se-
lection, 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 difficuit in
those Orders, such as Orthoptera, Hymenoptera, and Coleop-
tera, 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 stridu-
lating 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 sclection,
With buiterflics we have the best evidence, as the mules

330 The Descent of Man. Parr [1,

sometimes take pains to display their beautiful colours; and wa
cannot velieve that they would act thus, unless the display was
of use to them in their courtship.

When we treat of Birds, we shall see ihat they present in
their secondary svxual 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 brecding-
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 contined 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.

Fisurs: 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. AnfPiiBIaNs: Dit-
ferences in structure and colour between the sexes—Vocal organs.
Repries: Che'onians—Crocodiles—Snakes, colours in some cases pro-
tective—Lizards, battles of—Ornamental appendages—Strange dif-
ferences in structure between the sexes—Colours—Sexual difference
almost as great as with birds. °

Wk have now arrived at the great snb-kingdom of the Vertebrata.
wd will commen’e with the lowest class, that of Fishes. The

Cnap. XII, fishes. 331

males of Plagiostomous fishes (sharks, rays) and of Chineroid
- 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 hava
other parts of their bodies smooth. They are only temporarily
doveloped during the breeding-season ; and Dr. Giinther suspects
that they are brought into action as prehensile organs by tho
doubling inwards and downwards of the two sides of the body.
It isa remarkable fact that the females and not the males of
some species, as of Haiu cluvata, have their backs studded with
large hook-formed spines.'

‘Lhe males alone of the capelin (Mallotus v Uosus, one of
Salmonide), 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.? The widely distinct Monacanthus
scopas presents a somewhat analogous structure. The male, as
‘Dr. Giinther 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 ove 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 ot
the tail in the female are smooth. In some cther 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 de-
scribed 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.”

} Yarrell’s ‘Hist. of British 1871, p. 119.
Fishes,’ vol. ii. 1836, pp. 417, 425, 3 See Mr. R. Warington’s in.
436. Dr. Gunther informs me that ‘teresting articles in ‘Annals and
the spines in R. clavata ave peculiar Mag. of Nat. Hist.’ Oct, 1852 and
to the female. Nov. 1855.
*The American Naturalist,’ April

Pant Il.

332 The Descent of Man.

The males are said to be polygamists ;* they are extraordinarily
bold and pugnacious, whilst “the females are quite pacific.”
Their battles are at times desperate; “for these puny com-
“ batants 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,
iting and endeavouring to pierce each other with their raised
lateral spines. The same writer adds, “ the bite of these little
“furies is very severe. They also use their lateral spines with
“such fatal effect, that 1 have seen one during a battle absolutely
“rip his opponent quite open, so that he sank to the bottom and
“dicd.” 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 soine 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. Giinther. 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.”® 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.

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 (Figs. 27 and 28.) In our salmon this change of
structure lasts only during the breeding-season; but in the

« Noel Humphreys, ‘River Gar-
dens,’ 1857.

5 Loudon’s ‘ Mag. of Nat. History,’
vol. iii. 1830, p. 381.

6 «The Field,’ June 29th, 1867.
For Mr. Shaw’s statement, see
‘Edinburgh Review,’ (843. 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.

7 Yarrell, ‘History of Bvitisk
Fishes,’ vol. ii, 1836, p. 10.

Cuar. XIL Fishes. 393

Salmo lycaodon of N.-W. America the change, as Mr, J. K. Lord®
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

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. Gtinther.)

the teeth grow into regular fangs, often more than. half an inch
in length. With the European salmon, according to Mr. Lloyd,
the temporary hook-like structure serves to strengthen and

8 <The Naturalist in Vancouver’s ® ¢Scantinivian Adventures,’ vol
(sland,’ vol. i. 1866, p 54. i, 1854, pp. 100, 104.

334 The Descent of Man. Part IL,

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.

Fig 28 Head of female salmon.

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
eenera of the same family. The teeth of the male hecome sharp
onty when he is adult: whilst young they are broad and fiat

Cuar, XI, Fishes. 335

like those of the female. Asso 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 H. maculatu, 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.” 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. Carbonuier™ 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
manuer 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.

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.
Giinther. 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 Cullionymus lyra

10 See Yarrell’s account of the cellent figure, and p. 422, 432.
rays in his‘ Hist. of British Fishes.’ M As quoted in ‘The Farmer,
vol. ii, 1836, p. 416, with an ex- 1862, p, 369.

336 _ The Descent of Man. Parr IL

has been called the gemmevus dragonet “ from its briliiant 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 dragonct, was considered by Linnzeus, and
by many subsequent naturalists, as a distinct species; it is ofa
dingy reddish-brown, with the dorsal fin brown and the other

Fig. 29. Callionymus lyra. Upper figure, male; lower figure, female.
N.B. The lower fignre is more reduced than the upper,

fing white. The sexes differ also in the proportional size of the
head and mouth, and in the position of the eyes;? 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

“2 J have drawn up this description from Yarrell’s ‘ British Fishes,’vol. 1.
1836, pp. 261 and 266.

Cuap, XIL Fishes. 337

“ their mates.”'"* The young males resemble the adult females
in structure and colour. Throughout the genus Callionymus,'*
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 alsu a vreat difference
in colour between them. It is difficult, as Mr. Lloyd 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
miaztus, although very different in colour, are beautiful; the
male being orange with bright blue stripes, and the female
bright red with some b:ack spots on the back.

Fig. 30. Xiphophorus Hellerii. Upper figure, male; 1ower figure, female.

In the very distinct family of the Cyprinodontidee—inhabitants
of the fresh waters of foreign lands—the sexes sometimes differ
much in various characters. In the male of the Mollienesia
petenensis,® the dorsal fin is greatly developed and is marked

"8 ‘Nature, July 1873, p. 264. 16 With vespect to this and the
4 ¢Catalogue of Acanth. Fishes following species I am indebted to
in the British Museum,’ by Dr. Dr. Gunther for infermation: see
Giinther, 1861, pp. 138-151. also his paper on the ‘Fishes of
iS “Game Birds of Sweden,’ &c.. Central America, in ‘Transact.
1867, p. 466 Zoolog. Soc,’ vol. vi. 1868, p. 485.
O°

oo

338 The Descent of Man. Parr IT,

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 Xipho-
phorus Heiler’i (fig. 80), the inferior margin of the caudal fin is
developed into along filament, which, as I hear from Dr. Giinther,
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.”

In asiluroid fish, inhabiting the fresh waters of South America,
the Plecostomus barbatus (fig. 81), 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 ten-
tacles 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 stilf
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 Chimera 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.”

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,” 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 scrves 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

17 Dy, Gtinther makes this ree Water,’ July 1868, p. 377, with a

mark; ‘Catalogue of Fishes in the figure. Many other cases could be
British Museum,’ vol. iii. 1861, p. added of structures peculiar to the

141. male, of which the uses are not
18 See Dr. Giinther on this genus, known.
in ‘Proc. Zoolog. Soc.’ 1868, p. 252. *0 Dr. Gtinther, ‘Catalogue of

"F Buckland, in ‘Land and Fishes,’ vol. iii, pp. 221 and 240.

Cuap, XIT. Fishes 5 i 39

Upper figure, head of male; lower figure, female.

Hig 31. Plecostomas barbatus.

340 The Descent of Man. Part 11

neither sex is thus provided. In many of the Chromide, for
instance in Geophagus and especially in Cichla, the males, as ]
hear from Professor Agassiz,” 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 pro-
“ tuberance 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 caruncles on
the heads of certain birds; but whether they serve as ornaments
must remain at present doubtful.

I hear from Professor Agassiz and Dr. Giinther, 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.”™ An analogous and even greater change takes place
with the Sulmo eriox or bull trout; the males of the char
(4. umbla) are likewise at this season rather brighter in colour
than the females. The colours of the pike (/’som reticulatus) of
the United States, especially of the male, become, during the
breeding-season, exceedingly intense, brilliant, and iridescent.”
Another striking instance out of many is afforded by the male
stickleback (Gusterosteus ledurns), which is described by Mr.
Warington,” 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

#1 Sce also ‘A Journey in Brazil,” Mag. of Nat. History,’ vol. vi. 1841,
by Prof. and Mrs, Agassiz, 1868, p. p. 440.

220. <The American Agriculturist,’
# Yarrell, ‘British Fishes,’ vol. 1868, p. 100.
L 1836, pp. 10, 12, 3. 5 ¢ Annals and Mag. of Nat, Hist.’

78 W. Thompson, in ‘Annals and Oct. 1852.

Cnap. XII, Fishes. 341

“ 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. 8. Kent says that the
wale of the Labrus mixtus, which, as we have seen, differs in
colour from the female, makes “a deep hollow in the sand of tho
“tank, and then endeavours in the most persuasive manner to in-
* duce a female of the same species to share it with him, swim-
“ ming backwards and forwards between her and the completed
“ nest, and plainly exhibiting the greatest anxiety for her to follow.”
The males of Cantharus lincatus 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
“ouard over his respective hollow, and vigorously attacks and
© drives away any other fish of the same sex. Towards his com-
“ panions 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 meaus 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.”
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.” The
males are most beautifully coloured, more so tl:an 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’étalage de leurs vives couleurs chercher & attirer
“ Vattention des femelles, lesquelles ne paraissaient indifférentes
“ & ce manége, 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 par-
ticulars because, as we shall presently see, there are fishes, the

%8 ‘Nature,’ May, 1872, p. 25. 27 « Bull. de la Soc. d’Acclimat
earis, July 1869, and Jan. 1870.

342 The Descent of Man. Pant IL,

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 moxths
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 enquire 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. pano), described,” with pardonable exaggera-
tion, as formed of polished seales 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

28 Bory de Saint Vincert, in ‘ Dict. Class. d’Hist. Nat.’ tom. ix. 1826
p. 151.

Cuar. XII. Fishes.

343
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.” 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, ard
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”
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 Cyprinide in India are ornamented
with “bright longitudinal lines of various tints.”*' Mr. M‘Clel-
land, 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 tishes 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.

22 Owing to some remarks on this
subject, made in my work ‘On the
Variation of Animals under Domesti-
cation,’ Mr. W. F. Mayers (‘ Chinese
Notes and Queries,’ Aug. 1868, p.
123) has searched the ancient
Chinsse encyclopedias. He finds
that gold-fish were first reared in
confinement during the Sung Dy-
nasty, 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 uni-
“ versally admired, and there is not
“a household where it, is not cvl-
“tivated, in rivalry as to its colou-
“and as a source of profit.”

30 «Westminster Review,’ July
1867, p. 7.

31 «Indian Cyprinide,’ by Mr. J
M‘Clelland, ‘Asiatic Researches,
vol, xix. part ii. 1839, p. 230.

344 The Descent of Man. Pars IL

We have now to consider whether, when the male differs in a
marked manner from the female in colour or in other orna-
ments, he alone has been modified, the variations being inherited
by his male offspring alone; or whether the female has been
specially modified ana 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 “shes 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,
ean through the action of the nervous system, change their
colours in adaptation to surrounding objects, and that within a
short time. 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® 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,” 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 cure of their young when hatched. Both

% G, Povchet, LJactitut Now. 1, 327, pl. xiv. and xv.
Us71,p 134. Yarrell, ‘ British Fishes? vol,
P+ Seve, Zoulog, Soc’ 1865, p. ii, p. 11.

Cuap. X11. Fishes.

345

sexes of the bright coloured Crenilubrus massa and melops work
together in building their nests with sca-weed, shells, &c.*>
But the males of certain fishes do all the work, and afterwards
take exclusive charge of the young. Thisis the casc with the dull-
coloured gobies,* 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. leturus) 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, afte

depositing her eggs, were immediately devoured by some encmy

for he is forced incessantly to drive her from the nest.*”

The males of certain other fishes inhabiting South Americ
and Ceylon, belonging to two distinct Orders, have the extra
ordinary habit of hatching within their mouths or branchiai
cavities, the eggs laid by the females.* 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.” Thespecies 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-scason. 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,
“Tt 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

35 According to the observations
of M. Gerbe; see Guinthet’s ‘ Record
of Zoolog. "Literature, 1265, p.
194.

38 Cuvier, ‘Régne Animal,’ vol.
n, 1829, p. 242,

37 See Mr. Warington’s most
interesting description of the habits
of the Gusterusteus fccurus, in ‘Ane

nals and Mag. of Nat. Hist.’ Novem-
ber 1855.

38 Prof. Wyman, in ‘ Proc. Boston
Soc. of Nat. Hist.’ Sept. 15, 1857.
Also Prof. Turner, in ‘Journal of
Anatomy and Phys.’ Nov. 1, 1866,
p. 78. Dr. Giinther has likewise
described other cases,

346 The Descent of Man. Part 11.

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 biighter-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, su
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, «&c.)
the males have either marsupial sacks or hemispherical de-
pressions on the abdomen, in which the ova laid by the female
are hatched. The males also shew great attachment to their
young.’ The sexes do not commonly differ much in colour;
but Dr. Giinther believes that the male Hippocainpi are rather
brighter than the females. The genus Solenostoma, however,
offers a curious exceptional case,” 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 Sole-
nostoma 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 nnmber
of fishes, of which the males are either permanently or period-
ically 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

® Yarrell, ‘Hist. of British Fishes of Zanzibar,’ by Col. Playfair,
Fishes,’ vol. ii. 1836, pp. 329, 338. 1866, p. 137, has re-examined tha

“ Dr. Giiather, since publishing specimens, and has given me the
aw account of this species in ‘The above information.

Fishes.

Cuap. XII. 347
accordince 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 charac-
ters, the males originally varied, with their variations trans-
mitted 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
iusical. Dr. Dufossé, 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 vibra-
tion of the intrinsic muscles of the swim-bladder. By this latte1
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.*! 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
“ ulone make the noise during the spawning-time; and that it
“ is possible by imitating it, to take them without bait.”* Fyrom
this statement, and more especially from the case of Ophidium,
it is almost certain that in this, the lowest class of the Verte-
brata, 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.

41 ¢Comptes Rendus.’? Tom. xlvi.
-858, p. 353. Tom, xvii. 1858, p.
916. Tom. liv. 1862, p. 393. The
noise made by the Umbrinas (Serna
aguila), is said by some authors to
se move 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.

42 The Rev. C. Kingsley, is
‘Nature,’ May 1870, p. 40.

348 The Descent of Man. Parr II.

AMPHIBIANS,

Urodela.—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 T'riton pulmipes the hind-feet are pro-
vided with a swimming-web, which is almost completely
absorbed during the wintcr; so that their feet then resemble

Fig 32. Triton cristatus (half natural size, from B 1l’s ‘ British Reptiles ’).
Upper tigure, male during the breeding-scasun; lower figure, female.

those of the female. 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 (7riton punctatus and cristutus) 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 punctutus) is “ brownish-grey above, passing into yellow

43 Bell, ‘History of British Reptiles,’ 2nd edit. 1819, pp. 156-159.

Onar. XIL Amphibians.

“ 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* 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 Butrachia.—-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 niyricans,* 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 pass-
ing 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 *
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. Giinther
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 brecding-season on the front-legs of the male, by

which he is enabled to hold the
44 Bell, ‘History of British Rep-
tiles,’ Ind edit. 1849, pp. 146, 151,
45 ‘Zoology of the Voyage of the
« Reagle,”’ 1843. Bell, ibid. p. 49.
‘6 ¢ The Naturalist in Nicaragua,’
“874, p. 321,
47 The male alone of the [ufo

female.” It is surprising that

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

.

350 The Descent of Man. Paar IL

these animals have not acquired more strongly-marked sexual
characters; for theugh cold-blooded their passions are strong.
Dr. Giinther 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 vreeding-season, and with so much violence, that ono
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 Hyle, 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.® 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.*® For instance, in the edible frog (anu escul: nta)
“the sacs are peculiar to the males, and become, when filled
“ with air in the act of croaking, large globular bladders, stand-
“ ing 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.” In the several genera of the family the vocal orgars
differ considerably in structure, and their development in all
cases may be attributed to sexual selection.

REptTiLes.

Chelovia.—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 tc
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

8 Bell, ‘History of British 4° J. Bishop, in ‘Todd’s Cyciop
Rentiles,’ 1849, p. 93. of Anat. and Phys.’ vol. iv. ¢ 150d
80 Bell, ibid. p. 112-114.

Curae. XIL Reptiles.

351
the sexes unite." With the huge tortoise of the Galapagos
Islands (Testudo nigra) the males are said to grow to a larger
size thon the females: during the pairing-season, and at na
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.”

With the Zestudo eleyuns 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.”

Crocodilia,—The sexes apparently do not differ in colour; nor
do I know that the males fight together, though this is pro-
bable, for some kinds make a prodigious display before the
females. Bartram ™ 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 spins 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 subwaxillary glands of the crocodile, and pervades their
haunts.°® ;

Ophidia.—Dr. Giinther 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, he can almost always distinguish the male
from the female by his more strongly-pronounced tints; thus
the black zigzag band ou 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 8. Africa the Bucephalus
cupensis presents an analogous difference, for the female “is
* never so fully variegated with yellow on the sides as the
“ male.” ®® The male of the Indian’ Dipsas cynodun, 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 T'ragop.
dispar of the same country, the male is bright green, and the

8 Mr. ©. J. Maynard, ‘The

British India,’ 1864, p. 7.
American Natnralist,’ Dec. 1869, p.

54 ‘Travels through Carolina,

555,

8? See my ‘ Journal of Researches
during the Voyage of the “ Beagle,”’”
"845, p. 384,

33: Dr. Gtinther, ‘Reptiles of

&e., 1791, p. 128.
- $5 Owen, ‘Anatomy of Verte-
brates,’ vol. i} 1806, p. 615.

5@ Sir Andrew Smith, ‘ Zoolog,
S. Afriea: Reptilia,’ 1849, pl. x.

352 The Descent of Man. Paer IT

female bronze-coloured.*? 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.®®

During the breeding-season the anal scent-glands of snakes are
in active function ;** 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 tive
times to avoid a noose, with which they were at first easily
caught. An excellent observer in Ceylon, Mr. E. Layard, saw °°
a cobra thrust its head through a narrow hole and swallow a
toad. “ With this encumbrance he could not withdraw him-
self; finding this, he reluctantly disgorged the precious mor-
© sel, 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 scized 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 ca.ze
apparently feel some attachment towards each other.”

57 Dr. A. Giinther, ‘Reptiles of brates,’ vol. i. 1866, p 615.
British India,’ Ray Soc. 1864, pp. 80 “Rambles in Ceyli n.’ in‘ Annuals

304, 308. and Mag. of Nat. Hist.’ 2nd series,
58 Dr. Stoliezka, ‘Journal or vol. ix. 1852, p. 333.

Asiatic Soc. of Bengal,’ vol. xxxix. S| Dr. Gtinther, ‘Reptiles ef

1870, pp. 205, 211. British India,’ 184, v. 340.

*» Owen, ‘Azatemy of Verte

Cua. XII. Reptiles. 353

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 adorn-
ment 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 anthority of Dr. Gunther,” 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 secoud 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
rcinains to be explained, and this may perhaps be sexual
selection.

Snakes produce other sounds besides hissing. The deadly
Evhis curinuta 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 pro-
duces “a curious prolonged, almost hissing sound.” With
respect to the rattling of the rattle-snake, we have at last some
detinite information: for Professor Aughey states, 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
avother 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
ealled for the other. But it by no means follows from the
above fact that the rattle may not be of use to these snakes ia
other ways, as a warning to animals which would otherwise

62¢ Westmiaster Review,'July Ist, Sne.’ 1871, p. 196.

1867, p. 32. 64 ¢The American Naturalist,
“3 ly, Anderson, ‘Proc. Zoolog. 1875, p. 80.

24

354 Lhe Descent of Man. Part II,

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 J have my-
sclf 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; and this, as far as Dr. Giinther has been able ta
ascertain, is the general rule with lizards of all kinds. The
males alone of the Cyrtoductylus rubidus of the Andaman Islands
possesses pre-anal pores; and these pores judging from analogy
probably serve to emit an odour.**

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 Cophot/s ceylanira, the female has a dorsal crest,
though much less developed than in the male; and so it is, as
Dr. Giinther 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 tubercu-
lata. In the genus Sitana, the males alone are furnished with a
large throat-pouch (fig. 83), 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
sristuteilus, according to Mr. Austen, the throat pouch, which is
bright red marbled with yellow, is present in the female, though
in a rudimenta! condition. Again, in certain other lizards, both
sexes are equally well provided with throat pouches. Here we

6 Mr. N. L. Austen kept these 88 Stoliczka, ‘Journal of Asiatic
animals alive for a considerable Soc. of Bengal,’ vol. xxxiv. 1870, p
time; see ‘Land and Water,’ .uly 166,

2807, p. 9.

Ouar. XII. Reptiles. 355

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 appen-
dages 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 Fig.'3%. Sitana minor. Male with the
arrives at maturity, at which state pane (from Giinther’s
age the middle appendage is

sometimes twice as long as the head. Most of the species like-
wise 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.*

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 impu-
““ nity,”—I presuine from despair.®

There are other and much more
remarkable differences between the
sexes of certain lizards. The male
of Ceratophora asp:ra 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: ih the female it is quite Fig, 24. Ceratophora Stoddartti

.vudimental. In a second species — Pper figure, mule; lower Sgure,
of the same genus a terminal scale
forms a minute horn on the summit of the flexible appendage;

87 All the foregoing statements nificent work on the ‘Reptiles of
and quotations, in regard to Cophotis, British India, Ray Soc. 1864, pp.
Sitana and Draco, as well as the 122, 130, 135.
following facts in regard to Cerato- 88 Mr. Swinhoe, ‘Proc. Zoolog

phora and Chameleon, are from Dr. Soe.’ 1870, p. 240.
Gunther himself, or from his mag- :

356 The Descent of Man. Parr II,

and in a third species (C. Stoddartii, fig. 34) the whole appen-
dage 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. Giinther has remarked to me,
may be compared with the combs of gallinaceous birds, and
apparently serve as ornaments. —

Fig. 35. Chamvleon bifurcus. Upper figure, male; lower figure, female.

In the genus Chameleon we come to the acme of difference
between the sexes. The upper part of the skull of the male
C. bifurens (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

Cuap. XIL Reptiles. 357

Chameleon Owenti (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 integu-
inents of the body,
so that they are
identical in sth c-
ture with those o. a
bull, goat, or other
sheath - horned ru-
minant. Although
the three horns
differ so much in
appearance from
the two great pro-
longations of the
skull in C. bifurcus,
we can hardly doubt
that they serve the
same general pur-
Posed the eCOnomy: Fig 36. Chamaeleon Owenii. Upper figure, male

of these two ani- lower figure, femate.

mals. The first con-

jecture, which will occur to every one, is that they are used
by the males for fighting together; and as these animals are
very quarrelsome,® 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
8. Africa. In a Cordylus of the latter country, the male is
either much redder or greener than the female. In the Indian
Calotes nigrilubris 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.” We have seen that

6° Dr. Bucholz, ‘ Monatsbericht 70 Bell, ‘History of British
K. Preuss. Akad.’ Jan. 1874, p. 78. Reptiles,’ 2nd edit. 1849, p. 40.

358 The Descent of Man. Part IL

the males alone of Sitana possess a throat-pouch; and this is
splendidly tinted with blue, black, and red. In the Procfotretns
tenuis of Chile the male alone is marked with spots of blue,
green, and coppery-red.7 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 Culotes muria, which at this season has a
bright red head, the rest of the body being green.”

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 (Practotretus 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 appen-
Cages, were probably acquired by the males as an attraction,
and then transmitted either to their male offspring alone, or to
hotb 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 Brnrcs.

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

SEconDaRY sexual characters are more diversified and con-
spicuous 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

| For Proctotretus see ‘ Zoology
£ the Voyage of the “Beagle:
Reptiles, by Myr. Bell, p. 8. For
the Lizards of S. Attica, see ‘ Zovlogy
of S$. Africa: heptises, by Sir
Andrew Sinith, pl. £5 and 39. For

the Indian Calotes, see ‘Reptiles of
British India,’ by Dr. Gunther, p.
143.

7 Gunther in‘ Proc. Zoolog. Soc.’
1870, p. 778, with a coloured
figure.

Caar, XIII. birds. 359

with each other. They charm the female by vocal or instru-
mental 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 miy suppose serves to charm or excite the female; for that
excellent observer, Mr. Ramsay,! says of the Australian musk-
duck (Biziura lobita) 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. 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 hy 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 scnse 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
lumming-birds belonging to the genus Eustephanus, which
inhavit 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
ditfer slightly in the form of the beak. In another genus of
humming-birds (Grypus), the beak of the male is serrated along
the margin aud 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 gold-

1 ¢Tbis,’ vol. iii. (mew series) 1867, 2 Gould, ‘ Handbook to the Birds
p. 414, ef Australia,’ 1865, vol. ii, p 383

360 The Descent of Alan. Parr I

finch (Carduelis elegans), for I am assured by Mr. J. Jenner Weir
that the birdcatchers 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 sliglit
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 pug-
nacious, 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® 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; ani M. Montes de
Oca, in speaking of another genus of humming-bird, says that
two males rarely meet without a fierce aérial 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.”* With Waders, the males of the
common water-hen (Gullinula 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 spec-
tator.2 Mr. Blyth informs me that the males of an allied bird
(Gullicrex 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 lemorrhous) which “fight with great
spirit.’’®

The polygamous ruff (Much tes pruynar, fig. 87) is notorious
(or his extreme pugnacity ; and in the spring, the males, which
are considerably larger than the females, congregate day after

% Quoted by Mr. Gould, “Intro- Ireland: Birds,’ vol. ii. 1850, p.
duction to the Trochilide,’ 18€1, 327.
vw. 29. § Jerdon, ‘Birds of India,’ 1863,
© Gould, ibid. p. 52, vol. ii. p. 90.
W. Thompsen, ‘Nat, Hist. of

Cuar. XIII. Law of Battle. 361

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

‘The Ruff or Machetes pugnax (from Brehm’s ‘ Thierleben?.

“ig. 27.

362 The Descent of Man. Part Il,

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 orna-
ment. 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.” 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 ((airina muschatu); and where these fights have
“ occurred the river is covered for some distance with feathers.” ®
Birds which seem ill-adapted for fighting engage in fierce con-
flicts; 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 1o
fight; this is the case, according to Audubon, with one vt the
woodpeckers of the United States ( Picws auratus), although “ the
“ hens are followed by even half a dozen of their gay suitors.” ®

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 Cinclorumphus eruratis (allied to our
pipits) are by measurement actually twice as large as their
respective females.° With many other birds the females are
larger than the males; and as formerly remarked, the explana-
tion 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 poly-
gamous kinds, are furnished with special weapons for fighting
with their rivals, namely spurs, which can be used with fearful

7 Macgillivray, ‘Hist. Brit. i. p.191. For pelicans and snipes,
Birds,’ vol. iv. 1852, pp. 177-181. see vol. iii. pp. 138, 477.

® Sir R. Schomburgk, in ‘Journal © Gould, ‘Handbook of Birds of
of R. Geograph. Soc.’ vol. xiii. 1843, | Australia,’ vol. i. p. 3953 vol. ti. p
0, SL. 38:3

* “Ornithological Bicgraphy,’ vol.

uae XI. Law of Battle. 363

effect. It has been recorded by a trustworthy writcr™ that in
Derbyshire a kite struck at a game-hen accompanied by her
enickens, 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 Jong 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
Stanley, is known to fight desperately “in defence of his
‘€ seraglio,” so that one of the combatants is frequently found
dead.” An Indian partridge (Urtygornts guluris), the male of
which is furnished with strong and sharp spurs, is so quarrel-
some, “that the scars of former fights disfigure the breast of
“almost every bird you kill.” *

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 (Tetruo
uroguilus and 1’ tetria), 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 “cngage 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

1 Mr. Hewitt in the ‘Poultry Nat. Hist.’ vol. xiv. 1854, p. 63.

Book by Tegetmeier,’ 1866, p. 137. 13 Jerdon. ‘Birds of India,’ vol
2 Layard, ‘Annals and Mag. of iii. p. 574

364 The Descent of Man. Paw I

“creature.” At such times the black-cocks are so absorbed that
they become almost blind and dea’, but less so than the caper-
cailzie: 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.

The peacock with his long train appcars 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 (see fig. 51, p. 8397) has two
or more on each leg; and one of the Blood-pheasants (Jthaginis
cruentus) has been seen with five spurs. The spurs are generally
confined to the male, being represented by mere knobs or rudi-
ments in the female; but the females of the Java peacock (Pure
muticus) and, as Iam informed by Mr. Blyth, of the small fire-
backed pheasant (Luplocumus erythropthulmus) 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.’ Hence spurs may
he considered as a masculine structure, which has been occasion-
ally 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.

Various birds have spurs on their wings. But the Egyptian
goose (Chen ulopea ceyyptiacus) 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.
lartlett, 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. Ths 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 dug howling away. But it does not appear that the
spurs in this case, or in that of some of the spur-winged rails,

M Brehm, ‘Must. Thierleben, Sweden,’ &., 1867, p. 79.
1867, B. iv. s. 851. Some of the 'S Jerdon, ‘Birds of India: on
foregoiny statements wre taken from — Ithaginis, vol. iii, p- 523; on Gallo
L. Lloyd, ‘The Game birds of perdix, p. 541.

Caap, XIII. Law of Battle. 305

are larger in the male than in the female.’® In certain plovers,
however, the wing-spurs must be considered as a sexual cha-

Fig. 38. Palamedea cornuta (from Brehm), shewing the double wing-spurs, and the
filament on the head.

16 For the Egyptian goose, see p. 639. For Plectropterus, ‘Living-
Maéggillivray, ‘ British Birds,’ vol. iv. stone’s Travels,’ p. 254. For Pala~

366 The Descent of Man.

Part II,

racter. Thus in the male of our common peewit ( Vanellus cris-
tatus) 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.”

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,’ 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
(Astreldu amandava) fight together by placing three small cages
in a row, with a female in the middle; after a little time the twa
males are turned loose, and immediately a desperate battle en-
sues.9 When many males congregate ut the same appointed
spot and fight together, asin the case of grouse and various other
birds, they are generally attended by the females,” which after-
wards pair with the victorious combatants. But in some cases the
pairing precedes instead of succeeding the combat: thus accord-
jing to Audubon,” several males of the Virginian goat-sucker
(Caprimulgus virginiunus) “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

20 Richardson on Tetrao wmbellus
‘Fauna Bor. Amer.: Birds,’ 1831,
p. 343. L. Lloyd, ‘Game Birds of

meidea, Brehin’s ‘ Thierleben,’ B. iv.
s. 740. See also on this bird Azara,
‘Voyages dans |’Amerique merid.’

torn. iv. 1809, pp. 179, 253.

17 See, on our peewit, My. R. Carr
in ‘Land and Water,’ Aug. 8th,
1868, p. 46. In regard to Lobi-
vanellus, see Jerdon'’s ‘Birds of
India,’ vol. iii p. 647, and Gould’s
‘Handbook of Birds of Australia,’
vol. ii. p, 220. For the Holopterns,
see Mr. Allen in the ‘Ibis,’ vol, v.
1863, p. 156.

16 Audubon, ‘ Ornith. Biography,’
vol. ii. p. 4925 vel. i. pp. 4-13.

8 Mr. Blyth, ‘Land and Water,
1867, p. 212.

Sweden,’ 1867, pp. 22, 79, on the
capercailzie and black-cock. Brehm,
however, asserts (‘ Thierleben,’ &c.,
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
grey-hens in Scandinavia, and with
other species in N. America.

21 “Ornithological — Biography,
vol. ii, p. 275,

Cuap. XJIL Law of Battle. 367

“ them beyond his dominions ” Generally the males try to drive
away or kill their rivals before they pair. It dows 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 mnales trying
to distract the peace of an already mated pair. 2

Even with the most pugnacious species it is probable that the
puiring 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, aud 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 un-
consciously prefer them. In the case of Tetruo umbellus, a good
observer * goes so far as to believe that the battles of the males
“are all a sham, performed to show themselves to the greatest
advantage before the admiring females who assemble around ; for
“ Thave 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 Tttrao cupido of the United
States, about a score of mates assemble at a particular spot, and
strutting about, make the whole air resound with their extra-
ordinary 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
choiee, 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.” *

2 Brehm, ‘Thierleben,’ &e., B. *4 Audubon’s ‘Ornitholog. Bio-
iv. 1867, p. 990. Audubon, ‘ Ornith. graphy ;’ on Zetrao cupido, vol. ii,
Paography, vol. ii. p. 492. p- 492; on the Sturrus, vol. ii. p

23 «Land and Weter,’ July 25th, 219.

A848, p. 14.

368 The Descent of Man. Pasr IT,

Vocal and instrumental music.—With birds the voice serves to
oxpress various emotions, such as distress, fear, anger, triumph,
or mere happiness. It is apparently sometimes used to excite
terror, as in the casc of the hissing noise made by some nestling-
birds. Audubon” relates that anight-heron (Ard-a nycticorax,
Lim.) 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 ege, “ repeats the same note very often,
“and concludes with the sixth above, which she holds for a
longer time; ”*° 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 hy 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 tae 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 varions strange cries are chiefly uttered during the breed-
ing-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 “ malos 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
* eonspicuous spot, breathing out their full and amorous notes,
“which, by instinct, the female knows, and repairs to the spot to
“ choose her mate.”*7 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.”** There can be no doubt that birds
slosely attend to each other’s song. Mr. Weir has told me ot

25 ¢ Ornithological Biograph.’ vol. végel,’ 1840, s. 4. Mr. Harrison
v. p. 601, Weir likewise writes to me:—“I

26 The Hon. Daines Barrington,
‘Philosoph. Transact.’ 1773, p. 252.

27 ¢Ornithological Dictionary,’
1833, p. 475.

2% «Naturgeschichte der Stuben-

“am informed that the best singing
“males generally get a mate first,
“when they are bred in the same
“ room.”

Uap. XL. Vocal Music. 309

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 whero
other birds were kept and he began to sing, all the others, con-
sisting 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.” Bar-
rington, however, admits that “ superiority in song gives to
“ birds an amazing ascendancy over others, as is well known to
“ pird-catchers.”

It is certain that there is an intense degree of rivalry between
the males in their singing. Bird-fanciers match their birds to
sce 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,” 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 de-
scribed *! 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, aman 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
chaftinch 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,

29 ¢Philosophical Transactions,’ 50 <Naturgesch, der Stubenvéger,
1773, p. 263. White’s ‘Natural 1840, s, 252.
History of Selborne,’ 1825, vol. i. p. 31 Mr, Bold, ‘ Zoologist,’ 1843-44,
246, p. 659.

25

Part iL

370 The Descent of Man.

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 widow-
hood, 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,
for this disturbs all the usual functions connected with the repro-
duction of the specics. 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, be-
cause the males of certain species, for instauce of the robin, sing
during the antumn.® 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 ob-
viously 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 capercailzio
sometimes hold their Bulzen or leks at the usual place of as-
semblage during the autumn.** Hence it is not at all surprising
that male birds should continue singing for their own amuse-
ment 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,” and sometimes that of their neighbours.®* 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 Yavens, ciows, and magpies,

% D. Barrington, ‘Phil. Transact.’
1773, p. 262, Bechstein, ‘Stuben-
vogel,’ 1840, s. 4,

33 This is likewise the case with
the water-ouzel, see Mr. Hepourn
in the ‘Zoologist,’ 1845-1846, p.
1068.

34 L. Lloyd, ‘Game Birds of
Sweden,’ 1867, p. 25.
* Barrington, itid, p. 234.

possess the proper apparatus,”

Bechstein, ibid. s. 5,

3° Dureau de la Malle gives a
curious instance (‘Annales des Sc,
Nat.’ 3rd series, Zoolog. tom. a. p.
118) of some wild blackbirds in his
garden in Paris, which naturally
learnt a republican air from a caged
bird.

37 Bishop, in ‘Todd’s Cyclop. of
Anat, and Phys.’ vol. iv. p. 1496

Cuap. XIII. Vocal Music.

371

though they never sing, and do not naturally modulate their
voices to any great extent. Hunter asserts* 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 femaies.

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 “ cor-
rowrying places,” where they sing, raising and spreading their
tails like peacocks, and drooping their wings.” Itis also remark-
able 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, é&c., utter
harsh cries; and the brilliant birds of the tropics are hardly ever
songsters.*° 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.

In some birds the vocal organs differ greatly in the two sexes.
In the Tetrao cupido (fig. 89) 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 ot
the mouth of certain male frogs), for he found that the sound was
mich 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.”*" The
in Canada,’ by Major W. Ross King,

38 As stated by Barrington in ae
1866, pp. 144-146. Mr. T. W.,

‘Philosoph. Transact.’ 1773, p. 262.

in the ‘Student’ °

38 Gould, ‘ Handbook to the Birds
of Australia,’ vol. i. 1865, pp. 308-
810. See also Mr. T. W. Wood in
the ‘Student,’ Avril 1870, p. 125.

40 See remarks to this effect in
Gould’s ‘ Introduction to the Trochi-
nda,’ 1861, p. 22.

«1 ¢ The Sportsman and Naturalist

Wood gives
(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.

372 The Descent of Man. Part Ik,

male of another kind of grouse (Te/rao urophasianus), whilst
courting the female, has his “ bare yellow cesophagus inflated to
“a prodigious size, fully half as large as the body;” and he
then utters various grating, deep, hollow tones. With his neck-

‘ll

i

i

ae
: a) 2

qi

(T. W. Wood.)

Tetrao cupido: male.

Fig. 39.

feathers erect, his wings lowered, and buzzing on the gound,
and his long pointed tail spread out like a fan, he displays a
variety of grotesque attitudes. The cesophagus of the female is
not in any way remarkable.”

42 Richardson, ‘Fauna Bor, American: Birds, 1831, p. 359. Audubcn
bid, vol. iv. p. 507.

Ouar. XIII. Vocal Music. 373

Tt seems now well made out that the great throat pouch of
the European male bustard (Otis turdu), 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-

Fig. 40. The Umbrella-bird or Cephalopterus ornatus (mal«, from Brehm).

season of a peculiar sonnd resembling “ock.”* A crow-like
bird inhabiting South America (Cephalopterus ornatus, fig. 40) is
called the umbrella-bird, from its immense top-knot, formed of

48 The following papers have In this latter paper an excellent
been lately written on this subject: figure is given of the male Austra~
Prof. A. Newton. in the ‘Ibis,’ lian Bustard in full display with
1862, p. 107; Dr. Cullen, ibid. 1865, the sack distended. It is a singular
p. 145; Mr. Flower, in ‘Proc. Zool. fact that the sack is not developed in
Soc.’ 1865, p. 747; and Dr. Murie, all the males of the same species,
in ‘Proc. Zool. Soc.’ 1868, p. 471.

The Descent of Man.

374 Part IL,

bare white quills surmounted by dark-blue plumes, which it cau
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.**

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) itis 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.* In one of the ducks, however, namely Anus
punctata, the bony enlargement is only a little more developed
in the male than in the female.** But the meaning of these
differences in the trachea of the two sexes of the Anatide 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.’ 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.** 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

‘4 Bates, ‘The Natur.list on the of eight, and yet this bird (Jerdon,
Amazons, 1863, vol. ii. p. 284; ‘Birds of India,’ vol. iii. p. 703) ia

Wallace, in ‘Proc. Zool. Soc.’ 1850,
p. 206, A new species, with a still
larger neck-apperdage (C. pendu-
fiyer), has lately been discovered,
sce ‘Ibis,’ vol. i. p. 457.

4 shop, in Todd’s ‘Cyclop. of
Anat. and Phys.’ vol. iv. p. 1499.

‘© Prot. Newton, ‘Proc. Zoolog.
Soc.’ 1871, p. 651.

47 The spoonbil]l (Platalea) has
ts trachea convoluted into a figure

mute; but Mr. Blyth informs me
that the convolutions are not con-
stantly present, so that perhaps
they are now tending towards
abortion.

48 ‘Elements of Comp. Anat.’ by
R. Wagner, ing. translat. 1845, p.
111. With respect to the swan, as
given above, Yarrell’s ‘ Hist. of
British Birds,’ 2nd edit, 1845, vob
iii, p. 196.

Guar. XII. Lustrumental Music. 375

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.*® 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. The voice of the common rook is
known to alter during the breeding-season, and is therefore in
some way sexual. 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 w.th
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
tiack-weavers (Ploceus ?) congregate in a small party on the
bushes round a small open space, and sing and glide through

© C. L, Bonaparte, quoted in the Sweden,’ &c., 1867, pp. 22, 81.

Naturalist Library: Birds,’ vol. 51 Jenner, ‘Philesoph Transac
nv. p. 126. tions,’ 1824, p. 20,

60 J, Lloyd, ‘The Game Biids of

376 The Descent of Man. Pau I

the air with quivering wings, “which make a rapid whirring
“sound likea 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 (Capri-
mulgus) make a strange booming noise with their wings. The
various species of wood-peckers 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 pro-
duced is audible at a considerable distance, but cannot be
described ; and I feel sure that its source would never be con-
jectured 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
cesophagus thus becomes much swollen; and this probably acts
as a resonator, not only with the hoopoe, but with pigeons und
other birds.

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, neigh-
ing, or thundering noise (as expressed by different observers)
made by the common snipe (Scolopax gullinago) must have sw-
prised every one who has ever heard it. This bird, during the
pairing-season, flies to “ perhaps a thousand feet in height,” ana

52 For the foregoing facts see,
on Birds of Paradise, Brehm,
‘Thierleben,’ Band iii. s. 325. On
Grouse, Richardson, ‘Fauna Bor,
Americ. Birds,’ pp. 345 and 359;
Major W. koss King, ‘The Sports-
man in Canada,’ 1866, p. 156; Mr.
Haymond, in Prof. Cox's ‘Geol.
Survey of Indiana,’ p. 227; Audu-

bon, ‘American Oruitholog. Bio-
graph. vol, i. p. 216. On the
Kalij-pheasant, Jerdon,.‘ Be-ds of
Tndia.’ vol. ii, p. 533. On che

Weavers, ‘Livingstone’s Expeditior
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 Natu-
rajist,’ 1873, p. 672. The English
Night-jar likewise makes in the
spring a curious noise during its
rapid flight.

Cuar, XIL. Lustrumental Musee. 377

é

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

Fig. 41. ° Outer tail-feather of Scolopax gallinago (from ‘ Proc. Zool. Soc,’ 1858).

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 yapidly 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. frenaty
(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.®

In the male of the Chamepetrs 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 niyra, Mr. Salvin observed a male, which,
whilst it flew downwards “ with outstretched wings, gave forth
“ 9 kind of crashing rushing noise,’ like the falling of a tree.

Fig. 42. Outer tail-feather of Scolopax frenata,

Fig. 43. Outer tail-feather of Scolopax javensis,

54 Mr, Salvin, in ‘Proc. Zool.
Soc.’ 1867, p. 160. Iam much in-

53 See M. Meves’ interesting
paper in ‘Proc. Zool, Soc.’ 1858, p.

199. For the habits of the snipe,
Macgillivray, ‘Hist. British Birds,’
vol. iv. p. 371. For the American
snipe, Capt. Blakiston, ‘Ibis,’ vol. v.
1863, p. 131.

debted to this distinguished orni-
thologist for sketches of the feathers
of the Chamepetes, and for other
information.

378 The Descent of Man. Parr II,

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.* 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 in-
Fig. 44. Primary wing-feather of a stance, of Selasphorus platycercus,
fyoreus (om a sketch by Mire Sake When adult, has the first primary
vin). Upper figure, that of male; wing-feather (fig. 44), thus excised.
loner Jen corresponding feather Whilst fl ying from flower to flower
he makes “a shrill, almost whist-
ling noise ;”"* but it did not appear to Mr. Salvin that the noise
was intentionally made.

Lastly, in several species of a sub-genus of Pipra or Manakin,
the males, as described by Mr. Sclater, have their seco. dary wing-
feathers modified in a still more remarkable manner. In the
brilliantly-coloured P. delicioxa 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 (4, 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 hones 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.” *”

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 con-
clusion arrived at as to insects. It is not difficult to imagine
the steps by which the notes of a bird, primer'ly used as a
mere call or for some other’ purpose, might have been improved

56 Jerdon, ‘ Birds of India,’ vol. 57 Sclater, in ‘Proce. Zool. Soc.’
iii. pp. 618, 621. 1860, p 90, and in ‘Ibis,’ vol. iv.
5° Gould, ‘Introduction to the 1862, p. 175. Also Salvin, in
Tyochilide,’ 1861, p. 49. Salvin, ‘Ibis,’ 1360, p. 37.
‘Proc, Zoolog. Soc,’ 1867, p. 160.

+

Cuar. XUI. Vocal aud Instrumental Muste. 379

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

“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 corre-
sponding feathers, «, ¢, f, from the female.

a and d, fifth secondary wing-feather of mal and female, upper surface.
b and e, sixth secondary, upper surface. ¢ and f, seventh secondary, lower surface.

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

380 The Descent of Man. Parr Il

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-
dovs, 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, 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 phasianells, 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, sc
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
(Arden 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 (Cathurfes 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
cinerec) often rises a few feet or yards in the air above some
bush, and “ flatters 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
Tndian bustard (Otis bengulensis) at such times “rises perpen-
“dicularly 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
manceuvre several times, at the same time humming in a
peculiar tonc. Such females as happen to be near “ obey this

$8 The Nile Tributaries of Abyssinia,’ 1867, p. 203.

Cuap. XIU. Love Antics and Decoration. 381

“ saltatory summons,” and when they approach he trails his
wings and spreads his tail like a turkey-cock.”

But the most curious case is afforded by three allied genera ot
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
fee, are decorated with feathers, shells, bones, and leaves, aie
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 practisel under confinement, and Mr
Strange has described ® 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
“ Jast 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 tlic

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, Au-
dubon, ‘Ornith. Biography,’ vol. ii.
p. 51, and vol. iii. p. 89. On the
White-throat, Macgillivray, ‘ Hist.
British Birds,’ vol ii, p. 354. On

the Indian Bustard, Jerdon, ‘ Bir ls
of India,’ vol. iii. p. 618.

6° Gould, ‘ Handbook to the Birds
of Australia,’ vol. 1. pp. 444, 449,
455, The bower of the Satin
Bower-bird may he seen in the
Zoological Society’s Gardens, se-
gent’s Park.

382 The Descent of Man. Part IL

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.*! The ornaments, as mentioned

i, SS
“ill

® See remarks to this effect,on Animals.’ by Mr. J. Shaw, in the
the ‘Feeling of Beauty among ‘Athensum,’ Noy. 24th, 1866, p.681.

Bower-bird. Chlamy.era maculata, with bowrr (from Brehm).

bic. 45

Unap, XI1IL Decoration. 383

at the commencement of this chapter, are wonderfully diver-
sified. 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 (see fig. 39, ante) 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
eometimes ornamented with a beard, wattles, or caruncles. Such
appendages are generally brightly-coloured, and no doubt servo
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 Temminckit) 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. The African hornbill (Bucorax
ubyssinicus) inflates the scarlet bladder-like wattle on its neck,
and with its wings drooping and tail expanded “ makes quite a
“ grand appearance.”® ven 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.”

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,** 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

62 See Dr. Murie’s account with 6 ‘Land and Water,’ 1868, p.
coloured figures in ‘Proc. Zoolog. 217.
Soc.’ 1872, p. 730. 85 ¢ Ueber die Schadelhécker,’ &.,
63 Mr. Monteiro, ‘Ibis,’ vol. iv. ‘ Niederlandischen Archiv fir Zoo
86%, p. 339. logie,’ B. I. Heft. 2. 1872.

384 The Descent of Man. Parr II.

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.6 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, and that of the beautifully ocellated
secondary wing-feathers nearly three feet. In a small African
night-jar (Cosmetornis vexillurius) 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 elon-
gated wing-feathers are naked, except at the extremity, where
there is a disc. 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 ter-
minate 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 (Lumomota superciliaris), of a king-fisher, finch, hum-
ming-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.” It is a most singular
fact that the motmots, as Mr. Salvin has clearly shewn,” 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.

«6 Dy, W. Marshall, ‘UberdenVog- 1864, p. 114. Livingstone, ‘ Expedi-
elschwanz,’ ibid. B. I. Heft 2, 1872. tion to the Zambesi,’ 1865, p. 66,

87 Jardine’s ‘Naturalist Library: 8° Jerdon, ‘Birds of India,’ vol.
Birds,’ vol. xiv. p. 166. iii. p. 620.

®§ Sciater, wn the ‘Ibis,’ vol. vi. 7° « Proc, Zoolog. Soc,’ 1873, p. 429

Cuap. XI. Decoriation. 385

Again the barbs of the feathers in various widely-distinct
birds are filamentous or plumose, as with some herons, ibises,
birds of paradise, and Gallinacew. In other cases the barbs
disappear, leaving the shafts bare from end to end; and these in
the tail of the Paradisea apodu attain a length of thirty-fou
inches:” in P. Papuana (fig. 47) they are much shorter and
thin. Smaller feathers when thns 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 Sebas-
topol goose the scapular feathers are greatly elongated, curled,
or even spirally twisted, with the margins plumose.”

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’ sur-
rounded 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 appre-
ciated. 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.”” In anothcr

«1 Wallace, in ‘ Annals and Mag. 12 See my work on ‘The Variation
of Nat. Hist.’ vol. xx. 1857, p. 416; of Animals and Plants under Dume--
and in his ‘Malay Archipelago,’ tic.tion,’ vol. i. pp. 289, 293.
vol. ii. 1869, p. 390. 73 Quoted from M. de Latresnaye,

26

386 The Desceit of Man. Parr I

most beautiful species the head is bald, “and of a rich cobalt
“ blue, crossed by several lines of black velvety feathers.”

Puradizea Papuana (T. W. Wood)

Fig. a7.

in ‘Annals and Mag. of Nat. Hist.’ ‘Malay Archipelago.’

col. xiii, 1854, p. 157: see also Mr. 74 Wallace. ‘The Malay Archi-
Wallace’s much fuller account in pelago,’ vol. ii. 1869, p. 405.

vol. xx, 1857, p. 412, and in his

Csap. XIII. Decoration. 387

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 orna-
mented. Almost every part of their plumage has been taken
advantage of, and modified; and the modifications have been

RINE,

Fig. 48, Lophornis ornatus, male and female (from Brehm).

388 The Descent of Man. Part II,

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

Fig. 49. Spathura underwoodi, male and femile (from Brehm).

Onav, NTL Decoration. 389

saine species in other characters; and these have been seized on
by man and much augmented—as shewn by the tail of the fan-
tail-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, é&c., it is
due to the selection by the females of the more beautiful males.
I will mention only one other bird, remarkable from the ex-
treme contrast in colour between the sexes, namely the famous
bcll-bird (Chasmorhynchus niveus) of 8. 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 in-
offensive 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 mimute
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. nud-
ellis) 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. tricurwncaudutus) the head and neck alone of
the male are white, the rest of the body being chesnut-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.”
The coloured plumage and certain other ornaments of the
adult males are either retained for life, or are periodically re-
newed 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, &c. In the white ibis, the cheeks, the
inflatable skin of the throat, and the basal portion of the beak
then become crimson.” In one of the rails, Gaillicrem cristatus, a

7 Mr. Sclater, ‘Intellectual Ob- plate, in the ‘ Ibis,’ 1865, p. 90.
zerver,) Jan. 1867. ‘ Waterton’s i +Land and Water,’ 1867. p
Wanderings,’ p. 118. See also Mr, 304.

Salrius wterestirg paper, with a

390 The Descent of Man. Parr IL

large red caruncle is developed during this period on the heaa
st 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
tound covered with these curious exuvie.””

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
duJl-coloured margins being periodically shed, or on these three
processes more or less combined. The shedding of the de-
ciduary 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.”

With respect to the birds which annually undergo a double
moult, there are, firstly, some kinds, for instance snipes, swallow-
plovers (Glareole), 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 eases 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
iuale undergoes a greater amount of change at each reeurrent
season than the female—of which the ruff (Aduchetes pugnaz)
offers a good instance.

With respect to the cause or purpose of the differences in
evcloar between the summer and winter plumage, this may in
seme instances, as with the ptarmigan,” serve during both

7 Mr. D. G. Elliot, in ‘Proc. edited by P L. Sclater. Ray Soe.

ool. Soc.’ 1869, p. 589. 1867, p 14.
% Nutnsch’s = ¢ Ptorylography,’ 7” The brown mottled summa

Cuar. XILL Double Annual Moult.

391

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,
&ec., for they acquire their beautiful plumes only during the
breeding-season. Moreover, such plumes, top-knots, &c., 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) re-
tained 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.'?

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 orna-
mental 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

statements

‘
plumage’ of the ptarmigan is of as
mach importance to it, as a pro-
tection, as the white winter plu-
mage; 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 Wilbelin von Wright, in

Lloyd, ‘Game Birds of Sweden,’
1867, pe feo,
0 In regard +0 the previous

on moulting, see, on
snipes, &c., Macgillivray, ‘ Hist.
Brit. Birds,’ vol. iv. p. 371; cn
Glareolz, curlews, and bustards,
Jerdon, ‘ Birds of India,’ vol. iii. jp.
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.

Ee

392 The Descent of Man. Part Ii,

moult, and others only a single one. ‘The ptarmigan, for
instance, moults twice or even thrice in the year, and the black-
cock only once: some of the splendidly coloured honey-suckers
(Necturini) of India and some sub-genera of obscurely coloured
pipits (Anthus) have a double, whilst others have only a single
aunual moult." But the gradations in the manner of moulting,
which are known to occur with various birds, shew us how
apecies, 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 under-
go 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
(Bhringv) 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 re-
tained for the whole year, and the other completely lost. Thus
in the spring Much+tis 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 Maich; so that they are retained only for
about three months. Most species, which undergo a double
moult, keep their ornamenta] 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
uuderlying 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

§! On the moulting of the ptar- 359, 365, 569. On the moulting of
migan, s2e Gould’s ‘Birds of Great Anthus, see Blyth, in ‘Ibis,’ 1864,
Britain.’ On tha honey-suckers, — p. 32.

Jerdon, ‘Birds of India, vol. i. pp.

Duar. XTIL. Double Annual Moult.

393

that we here see, as to part of the plumage, a double moult
changed under domestication into a single moult.®

The common drake (Anas boschus) 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 pintail-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 extra-
“ ordinary 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 pintail 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,
tor 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.

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. Cbanges of colour thus
caused may last for a longer or shorter time. In the Pc/ecunus
ovscrotalus 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 Mringilla tristis
of the United States (as well as many other American species)

82 For the foregoing statements
in regard to partial moults, and
on old males retaining their nuptial
plumage, see Jerdou, on bustards
and plovers, in ‘ Birds of India,’ vol,
iii. pr. 617, 637, 709, 711. Also
Blyth in ‘Land and Water,’ 1867,
p. 84, On the moulting of Para-
disea, see an interesting article by
Dr. W. Marshall, ‘ Archives Neerlan-
Jaises,’ tom, vi. 1871. On the Vidua,
‘Ibis,’ vol. iii. 1861, p. 133. On
she Dyongo-shrikes, Jerdon, ibid.
vol, i. p. 435. On the vernal moult

of the Herodias bub-lcus, My. S. 8.
Allen, in ‘Ibis,’ 1863, p. 33. On
Gallus bankiva, Blyth, in ‘ Annats
and Mag. of Nat. Hist,’ vol. i. 1848,
p. 455; see, also, on this subject,
my Variation of Animals under
Domestication,’ vol. i. p. 236.

83 See Macgillivray, ‘ Hist. British
Birds’ (vol. v. pp. 34, 70, and 223),
on the moulting of the Anatide,
with quotations from Waterton and
Mentaga. Also Yarrell, ‘Hist. of
British Birds,’ vol. iii. p, 243.

394 The Descent of Man. Parr LL

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 rctaincd through-
out the year.*

Display by Mule 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
he 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. All natu-
ralists 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*® insists that the beautiful plum-
age 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.

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 oj
‘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 cyes, grotesque

34 On the pelican, see Sclater, ia
‘Pre. Zool. Soc.” 1868, p. 283.
On the American finches, see Au-
duboa, ‘Ornith, Biography,’ vol. i.
pp. 174, 221, and Jerder, * Birds of
todia,’ vol. ii, p. 383. On the
Fringitla cunnabinag of Madeira, Mr.
RB. Veraon Harcour:, ‘luis,’ vol. v.,

1863, p. 230.

85 See also ‘Ornamental Poultry,
by Rev. E. 8. Dixon, 1848, p. 8.

86 ¢ Birds of India,’ introduct. vol.
i. p. xxiv.; on the peacock, vol. iii.
p. 507. See Gozld’s ‘ Introduction
to the Trochilida,’ 1861, pp. 15 and
li.

Cuap. XII. Display by the Male. 395

appearance. Similar facts have already been given with respect
to grouse of various kinds. Turning to another Order. The
male Hupicola 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 brown-
ish-green, shaded with red, and has a much smaller crest. Sir
R. Schomburgk has described their courtship; he found one

— TSS

Tug. 50. Rupicola crucea, male (T. W. Wood).

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

The Descent of Man.

Paur IL

396

“ wabbled 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.2? With birds of paradise a dozen or more full-plumaged
males congregate in a trce to hold a danciug-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.*

The Guld 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.*® 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 court-
ship, 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 threat 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

87 Journal of RK. Geograph. Soc.’
vol. x 1840, p. 236.

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, ‘ Thierlvben,’ B, iii. s, 326.

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
versico/or ; and he calls it the lateral
or one-sided dispiay.

Cuap, XIIL Display by the Male. 397

eyes of the admiring female in one grand bespangled expanse.
‘ro whichever side she may turn, the expanded wings and the
obliquely-held tail are turned towards her. ‘lhe male Tragopan
pheasant acts in nearly the same manner, for he raises the
teathers of the body, though not the wing itself, on the side

Fig. 51. Polypl. ctron chinquis, mate (T. W. Wood).

398 The Descent of Man. Parr 11,

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.

The Argus pheasant affords a much more remarkable case. The
immensely developed secondary wing-feathers are confined to tlic
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
shews 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 himeseif, sometimes pushes his head between two of
the long wing-feathers (as Mr. Bartlett has seen), and then pre-
sents 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,” 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 tha
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 shewn 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

90 «The Reign of Law,’ 1867, p. 203

Crap. XIII Display by the Male. 399
AP. A

i ree black dots with a
i sists of two or three t
cai ue Rese But the chief Mirae ne ite
eae dark-blue shaft, ean area nore ig!
os i ithin the true ther. aia
sca : ga eee ee and is thickly dotted with minu
coloure

TS
Qopindari Create

a
ae

Fig. 62. Side view of male Arg sph Ww i yi re the female,
f le A t. ilst displaying before
vis pheasant, hilst ;
seinen Ub: ae and sketched trom nature by Mr. T. W. Wood.
St

400 The Descent of Man. Parr II.

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 featners are quite hidden on ail
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 asexual charm, and for no other purpose. We must con-
clude that this is the case, as the secondary and primary wing-
feathers are not at all displayed, and the ball and socket orna-
ments 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 purposcless; 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 remark-
able, as Mr. Bartlett informs me, that this is not the case with the
dull-coloured Eared and Cheer pheasants (Crossoptilon auritum
and Phasiunus 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 rico 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 like-
wise becomes 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,

Unar. XL Display by the Male. 401

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 samo
species; but in this case, the advantage gained would have been
the same, namely, success in charming the female. Nevertheless
it noust 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 tre
British Fringillide and Emberizide, 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
expandcd, 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.

27

402 The Descent of Man. Part LL.

Most of the British Buntings are plain coloured birds; but in
the spring the feathers on the head of the male reed-bunting
(Lmberiza schoeeniculus) 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. castanutis 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 con-
spicuous oval spots of white"! This species, when courting the
female, slightly spreads out and vibrates these parti-colourcd
tail-coverts in a very peculiar manner. The male Amadins
Luthumi 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 (Pycnorotus hemorrhous) 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.”
The crimson under tail-coverts of some other birds, as with one
of the woodpeckers, Picus majur, 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
toe 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 ex-
panded and quivering tail-feathers, he seems the very emblem
of pride and vanity.

®! For the description ~* shese p, 417.
hirds, see Gould’s ‘Bandboor ro the 8 ‘Birds of India,’ vol. ii, p. 96,
Birds of Austsalia,” vol... 1263,

Onap, XIIL Display by the Male. 403

The various ornaments possessed by the males are certainly
vf 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 are 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 in-
convenience 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 .o 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 01 approach, than the sombre coloured and compa-
ratively tame females, or than the young and as yet unadorned
males.”

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,

88 On the Cosmetornis, see Living- widow-bird, Barrow’s ‘Travels in
ytone’s ‘Expedition to the Zambesi,’ Africa,’ vol. i. p. 243, and ‘ Ibis,’
1865, p. 66. On the Argus pheasant, vol. iii. 1861, p. 133. Mr. Gould,
Jardine’s ‘Nat. Hist. Lib.:- Birds,’ on the shyness of male birds, ‘ Hand-
vol. xiv. p. 167. On Birds of book to Birds of Australia,’ vel. «
Paradise, Lesson, quoted by Brehm, 1863, pp. 210, 457.

‘Thierleben.’ 1. iii, ». 325. On the

404 The Descent of Man. Paar Ll

“he has him entirely :n his power. Even supposing that the
“ bird is not killed, the loss of blood suffered by an undubbed
* eock is much greater than that sustained by one that has becn
“trimmed.” 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 heauty of the glossy
black Spanish cock is much enhanced by his white face and
crimson comb; and no one who has ever secn 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 XI¥.
Brrps—continued.

Uhoice 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—Varia-
tions sometimes abrupt—Laws of variation—Formation of ocelli—
Gradations of character—Case of Peacock, Argus pheasant, and Urosticte.

Wuen 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 itis the object of the male to induce
the female to pair with him, and for this purpose he tries to ex-
cite 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 fat

5¢ Tegetmeier, ‘The Poultry Book,’ 1866, p. 129.

Onar. XIV. Length of Courtship.

405

more difficult to decide what qualities determine the choice of the
females; but here again we have some direct and indirect evi-
dence 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 pro-
longed affair, and partly on reiteration in the act of pairing.
Thus in Germany and Scandinavia the balzing 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 con.
gregate 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 Y%itrao phasiunellus
“last fora month or more.” Other kinds of grouse, both in
North America and Eastern Siberia,’ follow nearly the same
habits. The fowlers discover the hillocks where the ruffs con-
gregate 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.?

1 Nordman describes (+ Bull. Soc.
Imp. des Nat. Moscou,’ 1861, tom.
xxxiv. p. 264) the balzen of Zetrao
urogalloiddes in Amur Land. He
estimated the number of birds
assembled at above a hundred, not
tounting the females, which lie hid
in the surrounding bushes. The
noises uttered differ from those of
I. urogallus.

2 With respect to the assemblages

of the above named grouse see
Brehm, ‘Thierleben,’ B. iv. s. 3503
also L. Lloyd, ‘Game Birds of
Sweden,’ 1867, pp.19,78. Richard
son, ‘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.

406 The Descent of Man. Part IT.

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 cf 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 superb«) forms “small round hillocks,” and
the M. Alb-réi scratches for itself shallow holes, or, as they ara
called by the natives, corrohorying places, where it is believed
both sexes assemble. The meetings of the M. superba are some-
times very large; and an account has lately been published ® 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 hun-
‘red 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.‘

The common magpie (Corvus pica, Linn.), as I have been in-
formed by the Rev. W. Darwin Fox, used to assemble from all
parts of Delamere Forest, in order to celebrate the “ great mag-
pie marriage.” Some years ago these birds abounded in extra-
ordinary 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 flochs, chattering, sometimes fighting, bustling and flying
bout the trees. The whole affair was evidently considered by
the birds as one of the highest importance. Shortly after tho
mecting they all separated, and were then observed by Mr. Fox
and others to be paired for the season. In any district in which
@ species does not exist in large numbers, great assemblages
cannot, of course, be held, and the same species may have

* Quoted by Mr. T. W. Wood in of Australia,’ vol. i. pp. 300, 308,

the ‘Student,’ April, 1870, p. 125. 448, 451. On the ptarmigan, above
* Gould, ‘Handbook to the Birds alluded to, see Lloyd, ibid. p. 129.

Onav, XIV. Unpaired Birds. 407

different habits in different countries. For instance, I hava
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 conspic-
uous 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 succeed-
ing day; but Mr. Thompson gives the case of one being replaced
on the evening of thesame 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, ina case recently observed
by one of Sir J. Lubbock’s keepers. The first and most obvious
conjecture is that male magpies must be much more numerous
than females; and that in the above cases, as wellas in many
others which could be given, the males alone had been killed.
This apparently holds good in some instances, for the game-
keepers 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),

5 On magpies, Jenner, in ‘Phil. p.570. Thompson, in ‘ Annals ar]
fransact.” 1824, p. 21. Macgil- Mag. of Nat. Hist.’ vol. viii. 1842,
livray, ‘Hist. British Birds,’ vol. i. p. 494.

408 The Descent of Man. Part 1

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 peregtine-faleon (Falco peregrinus) is rare, yet Mr. Thompson
states that in Ireland “ if either an old male or female be killed
“in the breedivg-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 (“alco 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 (Aquilu chrysué/os), 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 slammew), “ 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 vhe males fighting, used to shoot them; and
though he had widowed the same female several times, she
always soon found afresh 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 (Phenicura ruti.
cilla), 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 ;
5ut the loss was always immediately repaized. During one

Cuae. XIV, Unpaired Birds. 409

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.®

These facts well deserve attention. How is it that there aro
birds enough, ready to replace immediately a lost mate of either
sex? Magpies, jays, carrion-crows, partridges, and some other
lards, 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, shew-
ing 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 Such contingencies as these probably
explain most of the foregoing cases. Nevertheless, it is a strange

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 Pheni-
cura, 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.

7 See White (‘Nat. Hist. of Sel-
borne,’ 1325, vol. i. p. 140) on the
existence, early in the season, of
small coveys of male partridges, of
which fact I have heard other in-
stances. See Jenner, on the retarded
state cf the generative organs in
eertain 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.

8 The following case has been
given (‘ The Times,’ Aug. 6th, 1868)
by the Rev. F. O. Morris, on the
authority of the Hon. and Rev. 0.
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
“eft one with its wings clipped as
“a decoy to destroy the old ores hy.

qLo The Descent of Man. Pant IL

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 Quulities 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. 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.”

“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 chari-
“table hawks, who had come with
‘an adopted feeling to succour the
“orphan. These two he killed, and
“then left the nest. On returning
“atterwards 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.”

® I am indebted to Prof. Newton
for the following passage from Mr.
Adam’s ‘Travels of a Nazuralist,’

1870, p. 278. Speaking of Japanese
nut-hatches in confinement he says:
“Thstead 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 interest-
“ing proof of intelligence on the
“part of these 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

onap. XIV. Mental Qualities. 4ll

Mr. Bennett relates" that in China after a drake of the beautiful
mandarin Teal had been stolen, the duck remained disconsolate,
though sedulously courted by anuther mandarin drake, who dis-
played 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
loeal 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 wouid 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 tuken 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.” They have good memories, for in
the Zoological Gardens they have piainly 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 mockiug-thrushes (M/mus 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

“moped, refused her food, and died 12 ¢ Acclimatization cf Parrots,’
“ of a broken heart.” by C. Buxton, M.P. ‘Annals and

M ¢Wanderings in New South Mag. of Nat. Hist.’ Nov. 1868, p.
Wales,’ vol. ii. 1834, p. 62. 381.

412 The Descent of Man. Part IL

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.”"* 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."

Mr. Jenner Weir is convinced that birds pay particular atten-
tion to the colours of other birds, sometimes out of jealousy, and
sometimes as a sign of kinship. Thus he turned a reed-bunting
(4mbrriza scheniculus), 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 Spizu 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. Myr. 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 intro-
duced, fly towards the species which resemble them most in
colour, and settle by their sides.

As male birds display their fine plumage and other crnamer-ts

¢The Zoo:ogist,’ 1847-1848, p. p. 39. Audubon on the wild turkey,
1602, ‘Ornith. Biography,’ vol. i. p. 14

\ Hewitt on wild ducks, ‘Journal On the mocking-thrush, ibid. vol. i
ef Horticulture,’ Jan. 13, 1863, p. 110.

Onay, XIV. Taste for the Beautiful. 413

with so much care before the females, it is obviously probahle
that these appreciate the beauty of their suitors. Itis, 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. Inother cases it is difficult to
distinguish between mere curiosity and admiration. It is per-
haps the former feeling which, as stated by Lord Lilford,” 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 (see fig. 46, p. 882), 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, whicn give it wheu fresh, a very pretty appearance.

15 The ‘ Ibis,’ vol. ii, 1860, p. 344.

The Descent of Man. Parr JL.

414

« Besides these there were several newly-picked leaves and
“ young shoots of a pinkish colour, the whole shewing a de-
© cided 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 dis-
“ covered ;” and the taste, as we see, of the several sp-cies
certainly differs.

Preference for particular Mules 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 Maegillivray relates how a male blackbird and
female thrush “fell in love with each other,’ and produced
offspring.” Several years ago eighteen cases had been recorded
of the occurrence in Great Britain of hybrids between the black
grouse and pheasant; 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” 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 widgeon
(Mareca penelope), living with females of the same species, has
been known to pair with a pintail duck, Querquedula ucuta.
Lloyd describes the remarkable attachment between a shield-
drake (Tudorna vulpanser) and a common duck. Many ad-

16 On the ornamented nests of
aumming-birds, Gould, ‘ Introduc-
tion to the Trochilide,’ 1861, p. 19.
On the bower-birds, Gould, ‘ Hand-
book to the Birds of Australia,’
1865, vol. i. pp. 444-461. Ramsay,
in the ‘ Ibis,’ 1867, p. 456.

17 ¢ Hist. of British Birds,’ vol. ii.

92.

18 <Zoologist,’
3946.

1 Waterton, ‘Essays on Nat.
Fist.’ 2nd series, pp. 42 and 117.

1853-1854, p.

For the following statements, sce on
the widgeon, Loudon’s ‘ Mag. of Nat.
Hist.’ vol. ix. p.616; L. Lloyd, ‘Scan-
dinavian Adventures,’ vol. i. 1854,
p. 452. Dixon, ‘Ornameutal and
Domestic Poultry,’ p. 137; Hewitt,
in ‘Journal of Horticulture,’ Jan.
13, 1863, p. 40; Bechstein, ‘Stu
benvogel,’ 1840, s. 230. Mr. J.
Jenner Weir has lately given me
an analogous case with ducks of two
species,

Crap, XIV. Preference by the Female. 4I§

ditional 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 comnion
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,
ereenfinches, 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
domestizated 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 licre related. Vitiated instincts may also account for some

416 The Descent of Man. Parr IL

of tho 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 (Ageleus phceniceus) 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 auru) 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 conadrnsis), 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 re-
“mained 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.”®” Many
similar statements with respect to other birds could be cited
from this same observer.

Turning now to domesticated and confined birds, I wil}
commence by giving what little I have learnt respecting the

20 Audubon ‘ Ornitholog. Biography,’ vol. i. pp. 191,249; vol. ii. pp. 42,
275; vol. iii. p. 2.

Cuap. XIV. Preference by the Female. 417

courtship of fowls. I have received long letters on this subject
‘rom 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 arti-
ficial state under which these birds have long been kept. Mr.
Tegetmeier is convinced that a game-cock, 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 circum-
stances 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.?!

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.”? 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
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
auccessively shut up with her for weeks; but on being let out
sne would have immediately accepted the first blue dragon that
offered. As she was a valuable bird, she was then shut up for

*\ ¢ Rare and Prize Poultry,’ 1854, Plants under Domestication,’ vl ii
p. oT. Pp 193,

«The Variation of Animals and

28

415 The Descent of Man. Part 2.

many weeks with a silver (ie., very pale bluc) male, and at last
mated with him. Nevertheless, as a general rule, colour appears
to have little influence on the pairing of pigeons. Mr. Teget-
meier, 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 Corbié, whose experience extended over forty-five years,
state: “Quand une femelle éprouve de l’antipathie pour un
* male avec lequel on veut Vaccoupler, malgré tous les fenx
“de Vamour, malgré lalpiste et le chénevis dont on Ja nourrit
“pour augmenter son ardeur, malgré un emprisonnement de
“six mois et méme d’un an, elle refuse constamment ses
“ caresses; les avances empressées, Jes agaceries, les tournvic-
“meus, les tendres roucoulemens, rien ne peut lui plaire ni
“Vémouvoir; gonflée, boudeuse, blottie dans un coin de sa
“ prison, elle n’en sort que pour boire et manger, ou pour re-
“« pousser avec une espéce de rage des caresses devenues trop pres-
“ santes.”*> 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, accord-
ing to another experienced observer, Riedel, are ofa profligate
disposition, and prefer almost any stranger to their own mate.
Some amorous males, called by our English fanciers “ guy
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.”

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 peacock. 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

23 Boitard and Corbié, ‘Les 24 «Die Taubenzucht,’ 1824, s. 86.
Pigeons, &.,’ 1824, p. 12. Prosper 5 ‘Ornithological — Biography,’
Lucas (‘Traité de lHéréd. Nat.’ vol. i. p. 13. See to the same effect,
tem. ii, 1850, p. 296) has himself Dr. Bryant, in ‘ Allen’s Mammals at 4
atserved nearly similai facts with Birds of Florida,’ p. 344.

Digeons.

Preference by the Female.

Snap. XIV, 4lg

* peacock to touch them. On his being let out in the autumn,
“ the oldest of the hens instantly courted him, and was success-
“ful in her courtship. Thenext year he was shut up ina stable,
“and then the hens all courted his rival.”** This rival was a
iapanned or black-winged peacock, fo 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 (Cheru 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.”
Here is an analogous case; Dr. Jaeger,” 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 col-
lector 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.” 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
aclicit his attention.®” We have seen that a tame wild-duck

26 *Proc, Zool. Soc.’ 1835, p. 54.
The japanned peacock is considered
by Mr. Sclater as a distinct species,
and has been named Paco nigri-
pennis; but the evidence seems to
me ta shew that it is only a variety.

27 Rudolphi, ‘Beytrage zur An-
thropologie,’ 1812. s, 18+.

28 «Die Darwin’sche Theorie, und

ihre Stellung zu Moral und Re-
ligion,’ 1869, s. 59.

28 This statement is given by Mi
A. Leith Adams, 1m his ‘ Field and
Forest. Rambles,’ 1873, p. 76, and
accords with his own experience.

30 Jn regard to peafowl, see Sir
R. Heron, ‘ Proc. Zoolog, Soc.’ 1835,
p. 94, and the Rev. k, S. Dison,

420 The Descent of Man. Parr IL

seduced an unwilling pintail drake after a long courtship. Mr.
Bartlett believes that the Lophophorus, like many other gallina-
ceous birds, is naturally polygamous, but two feinales 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 duli-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 sne met with a just re-
tribution, for, ceasing to be pugnacious, she was replaced by the
ald female, and the male then deserted his new and returned to
bis 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,
J 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 :”*
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 (Mareldu gluciulis), * it
has been remarked,” says M. Ekstrém, “that certain females
“are much more courted than the rest. Frequently, indeed,
“one sces an individual surrounded by six or eight amorous
“males.” Whether this statementis credible, I know not; but
the native sportsmen shoot these females in order to stuff them
as decoys.”

With respect to female birds feeling a preference for particular

‘Ornamental Poultry,’ 1848, p. 8. 3: Mr, Hewitt, quoted in ‘ Teget-
For the turkey, Audubon, ibid. p. 4. meier’s Poultry Bouk,’ 1866, p. 164,
For the capercailziv, Lloyd, ‘Game 32 Quoted in Lloyd’s Game Birds
Birds vf Sweden,’ 1867, p. 23. of Sweden,’ p. 345,

Onap, XIV. Preference by the I'emale. 421

males, we must bear in mind that we van 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 thefemales. 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 inereased 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 pro-
longed 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 peiring.

What then are we to conclude from these facts and considera-
tions? 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
gorgcous 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-hespangled 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;
nnd the mental powers of birds do not differ fundamentally from
ours. From these various considerations we may conclude that

422 The Descent of Man. Part IL,

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
oceasional 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 especiully 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. Variations may be divided into
two classes; those which appear to our ignorance to arise spon-
taneously, 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,** who shews

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 Euro-
pean birds. It is also an unsettled
point with naturalists, whether
several North American birds ought
to be rauked as specifically distinct
from the corresponding European
species. So again many North Ame-
rican forms which until lately were
named as distinct species, are now
considered to be local races.

34 “Mammals and Birds of East
Florida,’ also an ‘ Ornithological Re-
conaaissance of Kansas, &. Not-
withstanding the influence of cli-
mate on the volours 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 ap-
pears, 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 o/
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 tte
scenery in the above named countries
may not have affected the apprecia-
tion of bright colours by the birds
inhabiting them.

OHap. XIV,

Variability. 423

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 varia-
tious 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.
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®* that near
Bogota certain homming-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-

35 ‘Qrigin of Species,’ fifth edit.
1869, p. 104. I had always per-
ceived, that rare and strongly-
marked deviations of structure, de-
serving to be called monstrosities,
could seldom be preserved through
natural selection, and that the pre-
servation of even highly-beneficial
variations would depend to a certain
extent on chance. I had also fully
appreciated the importance of mere
‘ndividual differences, and this led
me to insist so strongly on the im-
portance of that unconscious form
of selection by man, which follows
from the preservation ot the most

~ breed.

valued individuals of each breed,
without any intention on his part
to modify the characters of the
But until I read an able
article in the ‘North British Re-
view ’ (March 1867, p. 289, ef 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 varia-
tions, whether slight or strongly
pronounced, occurring only in single
individuals.

36 <Tntroduct, to the Trorhilid.
p. 102.

The Descent of Man. Pant If

424

" yellow, while in others the same part is tinged with red.”*
In the United States some few of the males of the Scarlet Tanager
(Tunagra rubra) have “a beautiful transverse band of glowing
“red on the smaller wing-coverts;”® but this variation seems
to be somewhat rare, so that its preservation through sexual
selection would follow only under unusually favourable circum-
stances. In Bengal the Honey buzzard (Pernis cristatu) hes
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 sume species possessed in Southern India “a well-
“ marked occipital crest formed of several graduated feathers.” *

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 Briinnich to conclude that they were
specifically distinct; but this is now known to be an error.”
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“ 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 cha-
racter has caused the bird to be ranked by several ornithologists
as a distinct species under the name of JU. 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,” 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

37 Gould, ‘ Handbook to Birds of
Australia,’ vol. ii. pp. 32 and 68.

38 Audubon, ‘Ornitholog. . Bio-
graphy,’ 1838, vol. iv. p. 389.

% Jerdon, ‘ Birds of India,’ vol. i
p. 108; and Mr. Blyth, in ‘ Land
ind Water,’ 1868, p. 331,

" Graba, ‘ Tagebuch, Reise nach

Faro,’ 1830, s. 51-54. Macgillivray,
‘Hist. British Birds,’ vol. iii, p.
745. ‘Ibis,’ vol. v. 1863, p. 469.

41 Graba, ibid. s. 54, Macgile
livray, ibid. vol. v. p. 327,

2 ¢Variation of Animals and
Plants under Domestication,’ vol. ii
p. 92.

Cuap. XIV. Variability. 426

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
hays 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
ina state of nature and under domestication.“* 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 ?“4
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,*® the males
have intense crimson eyes, and those of the females are white.
In the Buceros bicurnis, 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;

43 On these points see also‘ Varia- of a Podica and Gallicrex in ‘ Ibis,’
tint of Animals and Plants under vol. ii. 1860, p. 206; and vol. v.
Domestication,’ vol. i. p. 253, vol. ii, 1863, p. 426.
ap. 73, 75. 4 See also Jerdon, ‘Birds of

44 See, for instance, on the irides India,’ vol. i. pp. 243-245,

426 The Descent of Man. Parr IL,

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 Chili*® 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, longitu-
dinal, leaden-coloured, fleshy crest or comb. Thecomb 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 iv 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 (dnser 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 ot 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 Créve-ceeur 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 gencrally causes any

“" Zoc'agy of the Voyage of H.M.S. Beagle,’ 1841, p. 6.

Cuap, XIV. Ocelli. 427

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
arc 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
detined; 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.*”

Formation and Variubility of the Ocelli or eye-like Spots on the
Plumage of Birds.—As no ornaments are more beautiful than the
acelli 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

47 Bechstein, ‘Naturgeschichte Deutschlands,’ B. iv. 1795, s. 31, on a
sub-variety of the Monck pigeon.

428 The Descent of Man. Part 1]

iris, but the central spot is often surrounded by additional con-
centric zones. The ocelli cn 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 8. African moth (Gyananis 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 (/ ipparchia
junira) exhibiting numerous gradations from a simple minute
black spot to an elegantly-shaded ocellus. In a S. African
butterfly (Cyl/o leda, Linn.), belonging to the same family, the
ocelli are even still more variable. In some specimens (A, fig. 58)
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 (A'), 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 (B').*8 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, 1t 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;** 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

‘8 This woodcut kas been en- wings of this butterfly, in his
graved from a beautiful drawing, ‘Rhopalocera Afriee Australis, Pp
most kindly made for me by Mr. 186.

Trimen ; see also his description of 1° Jerdon, ‘Birds of India,’ val
the weaderful ame~at of variation — iii. p. 517.
in the coloration ard shape of the

Cuap, XIV. Ocellt. 429

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 surround-
ing 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

Fig. 53, Cyllo leda, Linn., from a drawing by Mr. Trimen, shewing the extreme
range of variation in the ocelli.

A. S-ecimen, from Mauritius, upper - B. Specimen, from Java, upper surface
surface of fore-wing of hind-wing.
Al, Specimen, from Natal, ditto. Bl. Spccimen, from Mauritius, ditto.

of the common guirea-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 sur-
rounded by many successive zones of colour, have been generated,

[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 1s not a complex process, but depends on some slight
and graduated change in the nature of the adjoining tissues.

430 The Descent of Man. Parr IL

Gradtion of Secondary Sexual Churacters.—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 bis
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, in-
tensely 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 dise 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 else-
where described © 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 tae 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
seemed to deserve particular attention, as probably connected
with the development of the ocellus; but for a long time I could -
pot conjecture their meaning.

* ‘Variation of Animals and Plants under Domestication,’ vol. i. p. 254

Cuap. XIV. Gradation of Characters. 431

If we admit the principle of gradual evolution, there must
formerly have existed many species which presented every suc-
cessive step between the wonderfully elongated tail-coverts of
the peacock and the short tail-coverts of all ordinary birds; and
ayain 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
Gallinaces for any still-existing gradations. The species and

Fig. 54. Feather of Peacock, about two-thirds of natural size, drawn by Mr. Ford.
The transparent zone is r presented by the outermost white zone, cunfined to the
upper end of the disc.

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 in-
formed 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

432 The Descent of Man. Part II.

wing-feathers, which are ornamented with numerous ocelli. I
request the reader to turn back. to the drawing (fig. 51, p. 397)
of a Polyplectron. In P. napoleonis the ocelli are confined to
the tail and the back is of a rich metallic blue; in which re-
spects this species approaches the Java peacock. P. hardwichti
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. chinguis shades into brown,
edged with cream-colour, so that the ecellus 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.

Notwithstanding this approach, the first species of Poivplectron
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
cach side or the shaft. Hence I concluded that the early pro-
genitors of the peacock could not have resembled a Pulyplectron.
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. mutlaccense (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 cnd. 1+ is also iwanifest that if the convergence were

Guar. XIV. Birds—Gradation of Characters.

433

strongly pronounced and the confluence complete, the indentation
at the convergent end would tend to disappear.

The tail-feathers in both species
of peacock are entirely destitute
of ocelli, and this apparently is
related to their being covered up
and concealed by the long tail-
coverts,
differ remarkably from the tail-
feathers of Polyplectron, which
in most of the species are or-
namented 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 dis-
appear; and to my great satis-
faction, 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 tle
outermost feather. Again, in P.
malaccense, the ocelli on the tail-
coverts are, as we have secn,
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. Conse-

In this respect they.

Fig. 55. Part of a tail-covert of Poly-
~ pl ctron ch nquis, with the two ocelli
of nat, size,

nf

YY
Y vel

" :)

‘A
Fig. 56. Part of a tail-covert of Poly-
plectron malaccense, with the two
ocelli, partially confluent, of nat. size,

quently the tail-coverts and tail-feathers of this species of Poly-
plectron make a near approach in structure and «rnamentation
to the corresponding feathers of the peacock.

£9

434 The Descent of Man. Pant IL

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 progeni-
tor 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-eoverts, 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 in-
explicable. 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 of the most beautiful males, rendered
the peacock the most splendid of living birds.

Argus pheasa::t.—Another excellent case for investigation is
offered by the oceili on the wing-feathers of the Argus pheasani,
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 expcrienced 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 ot
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 cluc to the problem, and they prove to de-
monstration that a gradation is at least possible from a mere
spot to a finished ball-and-socket ocellus.

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 runuing obliquely down the outer side of the

Cuap. XIV. Birds—Gradation of Characters. 433

shaft to one of the ocelli. The spots are generaiiy 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 adjvining
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 per-
fect ball - and - socket
ocellus. This consists
of an intensely black
circular ring, surround-
ing a space shaded so
as exactly to resemble
a ball. The figure here
given has been ad-
mirably drawn by Mr.
Ford and wellengraved,
but a woodcut cannot
exhibit the exquisite
shading of the original.
The ring is almost
always slightly broken
or interrupted (see fig.
57) at a point in the
upper half, a little to
the right of, and above

G Fig. 57. Part of secondary wing-feather of Argus
the white shade on the Tiealiil. shewing two perfect ocelli, @ and b

enclosed ball: it is also ‘A, B, C, D, &c., are dark stripes running vbliqi ely
sometimes breaker: to- down, each to an ocellus.

{Much of the web on both sides, esp cially to the
wards the base on the ett of the shaft, has been cut off.]
right hand. These
little breaks have an important meaning. ‘The ring is always
much thickened, with the edges ill-defined towards the Ictt-
hand upper corner, the feather being held erect, in the posi-
tion 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

430 The Descent of Man. Past IL,

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 sepa-
rated 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 notin the least interfere
with the perfect shading of the ball. It should be particularly
observed that each vcellus stands in obvious connection either
with a dark stripe, or with a longitudinal row of dark spots, for
both occur indifferently on thesame feather. Thus in fig. 57 stripe
A runs to ocellus «; B runs to ocellus }; stripe C is broken in
the upper part, and runs down to the next succeeding ocellus,
not represented in the wood-
cut; 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 bear-
ing irregular black marks.

I will next describe the
other extreme of the series,
uamely, the first trace of
an ocellus. The short se-
condary wing- feather (fig.
58), nearest to the body,
is marked like the other
feathers, with oblique, lon-
gitudinal, rather irregular,
rows of very dark spots.
The basal spot, or that near-
est the shaft, in the five lower
rows (excluding the lowest
one) is a little larger than

4 the other spots cf the same

Fig. 5%. Basal part of the secondary-wing row, and a little more elon-

feather, nearest to the body. A ‘

gated in a transverse direc-

tion. 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

Cuar, XIV, Birds—Gradation of Characters. 437

the same row. ‘he 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 (tig. v9). We here see several oblique rows, A, B, C, D,

A B Cc

A, b, C, D, &. Rows of spotsrunning c. The next succeeding spot or mark in

down to and forming the elliptic the same row,
ornaments, d. Apparently a broken pro’ongation of
b. Lowest spot or mark in row B. the spot c in the same row B

&c. (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 (4) is
thicker and considerably longer than the upper spots, and has
its left extremity pointed and curved upwards. This black mark

438 The Descent of Man. Part il.

is abruptly bordered on its upper side bya rather broad space of
richly shaded tints, beginning with a narrow brown zone, which
passes into orange, and this into a pale Jeaden 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 (})
corresponds in every respect with the basal shaaed 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 (0 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 (/). 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 conflucnce with a broken and prolonged
part of the next spot above; but I do not feel sure of this. These
three marks, }, 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 can-
not be appreciated in the drawing, as the orange and leaden tints,
contrasting so well with the black marks, cannot be shewn.
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 (6 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 con-
fluent, forming an irregular elliptic ring. This ring is gradually
rendcred more and more circular and regular, increasing ai the
same time iu diameter. I have here given a drawing (fig. 61))
of the natural size ofan ocellus notas yet quite perfect. The lowcr
part of the black ring is much more curved than is the lower
mark in the elliptic ornament (0 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 munch concentrated; and beneath it the surface is
brighter cotoured than in a perfect ball-ard-secket ocellas. Evcu

Cuar. XIV. Birds—Gradation of Characters. 439

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
(¢ 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 (see
fig. 57), and this follows from the
lower black mark of the elliptic
ornament (@ fig. 59) having origi-
nally been thicker than tbe upper
mark (¢). Every step can be fol-
lowed 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, 8, ¢, d, of
the elliptic ornament. The irre- Z HMM
gular zigzag black marks between ig. 69. An ocellus in an inter.
the successive ocelli (see again fig. elliptic ornament and the perfect
57) are plainly due to the breaking _Dall-and-socket ocellus,

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 leaden 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 ren-
dered 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)
waving some dull fulyous shading on its upper side.

440

The Descent of Mun.

Part Il

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

apwards and become confused ; and above this limit the whole

Ye
Fiz. 61. Portion near summit of one of

the secondary wing-feathers, beariug
perfect ball-and-socket ocelli.

a. Ornamented upper part.

b Dypermost, 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.

upper end of the feather () is
covered with white dots, sur-
rounded by little black rings,
standing on a dark ground.
The oblique stripe belonging to
the uppermost ocellus (6) is
barely represented by a very
short irregular black mark with
the usual, curved, tranverse base.
As this stripe is thus abruptly
cut off, we can perhaps under-
stand 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 prolonga-
tion 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
obliqnely 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. Ishould 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 deticient, 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 dows to the

same ocellus

Cuar. XIV. Birds—Gradation of Characters. 44]

There still remains another very curious point, first observed
by Mr. T. W. Wood,” which deserves attention. Ina photograph,
given me by Mr. Ward, of a specimen mounted as in the act of
lisplay, it may be seen that on the feathers which aye 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 like-
wise 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 aa artist would have shaded them. Never-
theless 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 suffi-
ciently lateral. We have, however, no right tu expect absolute
perfection in a part rendered ornamental through sexual selec-
tion, any more than we have in a part modified through natural
selection for real use; for instance in that wondrous. organ the
humaneye. 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, ho
would have thought himself fully justified in returning it.°?

_ 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
adinits 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

The ‘Field,’ May 28, 1870. Subjects,’ Eng. trans. 1873, pp. 219

Popular Lectures om Scientific 227, 269, 390,

442 Lhe Descent of Man. Parr VI

spots, togethe: 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 then 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 orna-
ments 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 malcs 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 benjumini, 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 fail differs remarkably in both sexes of many kinds of
humming-birds, Mr. Gould does not know a single species, be-
sides the Urosticte, in which the male bas .the four central
feathers tipped with white.

The Duke of Argyll, in commenting on this case,*® 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 J quite agree with him, But
tan this be so confidently said of sexual selection? Seeing in
asw many ways the tail-feathers of humming-birds differ, why
rhould 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 ai

53 «The Reign of Law,’ 1867, p. 247,

ean XIV. Birds —Grudation of Characters. $43

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 twa
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 centrai 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 preduced 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,** after describing the beauty of the Florisuga mellivura, says,
* T 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.”© 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,
bnt in rivalry with other males, and would have left a larger
pumbcer of offspring to inherit their newly-acquired beauty.

>The Naturalist in Nicaragua,’ 55 ‘Introduction to the Froubi-
#874, p, 112 liue,’ 1861, p. 110,

144, The Descent of Man. Paar I.

CHAPTER XV.
BIRDS—continued.

Mscussion a: ts why the males alone of some species, and both sexes cf
others, are o1ight!y 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’? 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 | 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,? 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
ifs 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

' Fourth edition, 1866, p. 241. 1867. ‘Journal of Travel,’ vol. i
© < Westminster Review,’ July, 1808, p. 75.

Caar. XV, Birds—Sexrually Limited Inheritance. 445

imaginary illustration will best aid us in seeing the difficulty of
the case: we may suppose that a fancier wished to maku 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 trans-
mitted to both sexes equally, the fancier would have to try tx
convert this latter form of inheritance into scxunlly-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 com-
pelled 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, é&c., 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
ucquire so strong a latent tendency to pale-blueness, that they
would not destroy this colour in their male offspring, thei
female offspring still inheriting the slaty tint. If so the desired
cnd 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 Soommerring’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 femaie
Semmerring 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 Scemmerring pheasant, were crossed with the male

446 The Descent of Man. Part IT

of the latter, the male hybrid offspring would have a much
shorter tail than that of the pure offspring of Sceumerring’s
pheasant.

Our fancier, in order to make his new breed with the males
of a pale-blue tint, and the females unchanged, would have ta
continue selecting the males during many generations; anc
each stage of paleness would have to be fixed in the males,
and rendered latent in the females. The task would be én
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-bluc
offspring.

On the other hand, if one or two males were to vary ever sc
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‘ in which the males alone are
marked with black strie. So again Mr. Tegetmeier has recently
shewn® 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 grand-
father, 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 transmis-
sion to the male sex, habitually occur. When this form of

3 Temminck says that the tail of For the common pheasant, see
the female Phasianus Semmerringit Macgillivray, ‘Hist. Brit. Birds,’
is only six inches long, ‘Planches vol. i. pp. 118-121.
colorides,’ val. v. 1838, pp. 487 and 4 Dr. Chapuis, ‘Le Pigeon Vora
488: the measuzements above given ger Belge,’ 1865, p. 87.
were male tor ae by Aly Selat-r. 5 ‘Tne * Field. Sept. £872.

CHar, XV. Birds—Sexually Limited Inheritance. 447

inheritance prevails, it might well happen that some of the
successive variations would be transferred te 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 colvuur.

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 suc-
cessive 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 cach other, and from the two sexes of the abori-
ginal Gallus bunkiva; 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
mmale, 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 wonld 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 impossib'e process, to change one form
of transmission into the other through selection. Therefore,

448 The Descent of Man. Part 1.

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 cof successive variations, which were from the
irst 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. Conse-
quently 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 feniales whic varied in brightness, or which
received through inheritance from the males any marked ac-
cession of brightness, would sooner or later be destroyed. But
the tendency in the males to continue for an indefinite period
transmittimg to their female offspring their own brightness,
would have to be eliminated by a change in the form of in-
heritance; and this, as shewn by our previous illustration,
would be cxtremely 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 elimi-
nated, yet they would not be favoured or selected, for the male
usually accepts any female, and does not select the more at-
tractive individuals; consequently these variations would be
liable to be lost, and would have little influence on the character
of the race; aud this will aid in accounting for the females being
zommonly duller-coloured than the males.

In the eighth chapter instances were given, to which many
night nere be added, of variations occurring at various ages, and
inherited at the corresponding age. It was also shewn that va-
riations which occur late in life are commonly transmitted to the
asme sex in which they first appear; whilst variations octurring

cnae, XV. Birds— Development of Spurs. 449

early in life are apt to be transmitted to both sexes; not that all
the cases of sexually-lmited transmission can thus be accounted
for. It was further shewn that if a male bird varied by be-
coming 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
lull colours, bright tints would be far more dangerous to the
_young and inexperienced, than to the adult males. Conse-
quently 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 suc-
cessful in their courtship, the males alone would acquire bril-
liant 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 moditied 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 pro-
tection. 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 *® 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
Gallinacese 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

® Bechstein, ‘Naturgesch. Deutschlands,’ 1793, B. iii. ». 339.
ua)

450 The Descent of Man. Part IL.

in the female as in the male; though in not a few cases they ara
rather larger in tle 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 abori-
ginally 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 pro-
genitors of the existing spur-bearing species were once encum-
bered with an injurious appendage.

In some few genera and species, as in Galloperdix, Acomus,
and the Javan peacock (Puvo 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, indepen-
dently of natural selection. With the many females in which
spurs appear as rudiments, we may conclude that some few of
the successive variations, through whieh 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 pro-
ducing sound, as well as the proper instincts for using them,
often differ in the two sexes, but are sometimes the samein 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.’ It is

7 Daines Barrington, however, cubation. He adds, that a similar
thought it probable (‘ Phil. Transact.’ view may possibly account for the
1773, p. 164) that few female birds inferiority of the female to the
sing, because the talent would have male in plumage.
been dangerous to them duricg in-

Snare, XV Birds-—Length of Female’s Tail. 451

a safer conclusion that, as vocal and instrumental organs are of
Rpecial service only to the males during their courtship, these
organs were developed through sexual selection and their con-
stant 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 ; these 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 occuring
in the same group of birds. It would be difficult to account for
such a difference between the sexes by the female having been
henefited 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 accompany-
ing her young. Hence there is not the least @ prir/ improba-
bility in the development of her tail having been checked
through natural selection. But the females of various phea-
sants, which apparently are exposed on their open nests to as
much danger as the peahen, have tails of consid:rable length.
The females as well as the males of the Menura superba have
ong tails, and they build a domed nest, which is a great
anomaly in so large a bird. Naturalists have wondered how the
tewale Menura could manage her tail during incubation: but it
is now known ® 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
(Tunysiptera sylvia) have the middle tail-feathers greatly length-
ened, 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 °

® Mr. Ramsay, in ‘ Proc. Zoolog. Soe.’ 1888, p. 50.

452 The Descent of Man. Page I

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 pro-
geny, and thus have prevented the peacock from acquiring hia
present magnificent train. We may therefore infer that the
length of the tail in the peacock and its shortness in the pea-
hen 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 tailis of eyual length in both
sexes, namely, sixteen or seventeen inches ; in the common phea-
sant it is about twenty inches long in the male and twelve in the
female; in Scemmerring’s pheasant, thirty-seven inches in the
male and only eight in the female; and lastly in Reeve’s phea-
sant 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 selec-
tion. 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,’ 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
eontrast 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, cer-
tainly seems tv iavoar the belief that the females which sit ov

® ¢ Journal of Travel,’ edited by A. Murray, vol. i. 1868, p. 78.

suar. XV, Birds—Colour and Nidification. 453

open nests have been specially modified for the sake of protec-
tion; 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 e
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” 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
LPyranga estiva one of the most splendid birds in the United
States, the male being vermilion, and the female light brownish~
green. Nowif 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 com-
pensated some additional danger.

Mr. Wallace admits that with the King-crows (Dicrurus),
Orioles, and Pittide, 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; 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 con-
spicuously 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.

‘© ¢Journal of Travel,’ edited by 12 Jerdon, ‘Birds of India,’ vol.
A. Murray, vol. i. 1868, p. 281. ii. p. 108. Gould’s ‘Handbook of
Audubon, ‘ Ornitnological Bio- the Birds of Australia,’ vol. i. p. 463.
graphy,’ vol. i. p. 233. 18 For instance. the female Mupe

454 The Descent of Man.

In regard to birds which build in holes or construct domed
nests, other advantages, as Mr. Wallace remarks, besides con-
cealment are gained, such as shelter from the rain, greater
warmth, and in hot countries protection from the sun; so that
it is no valid objection to his view that many birds having both
sexes obscarely coloured build concealed nests.’® 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 hcle 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;'® yet female horn-bills are not more con-
spicuously 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. Thisis the case with the
Gralline of Australia, the Superb Warblers (Maluride) of the
same country, the Sun-birds (Nectariniz), and with several of
the Australian Honey-suckers or Meliphagidee.””

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 con-
spicuousness, 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,

Parr Ii,

tomena 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 hack 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.

14 Mr, Salvin noticed in Guate-
mala (‘Ibis,’ 1854, p. 575) that
humming-birds were mych more
unwilliag to ‘eave their ne. ts 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.

15 | may specify, as instances of
dull-coloured birds building con-
cealed nests, the species belonging
to eight Australian genera, de-
scribed in Gould’s ‘ Handbook of the
Birds of Australia, vol. i. pp. 340,
362, 365, 383, 387, 389, 391, 414.

16 Mr. C. Horne, ‘Proc. Zoolog.
Soc.’ 1869, p. 243.

17 On the nidification and colours
of these latter species, see Goul.l’s
‘ Handbook,” &c., vol. i. pp. 504, 327

Cusp. XV. Birds—Colour and Nidification,

455

the remaining twenty-eight being inconspicuous.’® Nor is there
wny close relation within the same genus between a well-pro-
nounced difference in colour between the sexes, and the nature
of the nest constructed. Thus the male house sparrow (/asser
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 (Musicapu
grisolu) can hardly be distinguished, whilst the sexes cf the
pied fly-catcher (Mf. luctuosw) differ considerably, and both
species build in holes or conceal their nests. The female black-
bird (Turdus merula) differs much, the female ring-ouzel (T.
turquatus) differs less, and the female common thrush (7. 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, scoticvs) 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” 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 (Capitonide), plantain-
eaters (Musophage), 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

18 T have consulted, on this sub-
ject, Macgillivray’s ‘ British Birds,’
and though doubts may be enter-
tained in some cases in regard to
the degree of concealment of the
nest, and to the degree of con-
spicuousness of the female, yet the
following birds, which all lay their
eggs in holes or in domed nests, can
nardly be considered, by the above
stindard, as conspicnous: Passer,
2 species; Sturnus, of which the
female is considerably less brilliant
than the male; Cinclus ; Motacilla

boarula (?); Erithacus (?); Fru-
ticola, 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 -onspicvots,
according to the same standard,
viz., Pastor, Motacilla alba, Parus
major and P. ceruleus, Upupa, Picus,
4 sp., Coracias, Alcedo, and Mer ips.
18 «Journal of Travel,’ elited by
A. Murray, vol. i. p. 78.

456 Lhe Descent of Man. Parr IL

from their manner of nidification. According to this view, their
present manner of nesting was acquired before their present
colours. Butit 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 Jed to chenge their instincts (supposing that they
originally built open nests), and to seex protection by building
domed or concealed nests. No one who studies, for mstance,
Audubon’s account of the differences in the nests of the same
species in the Northern and Southern United States, 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 manuer 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 Dro-
molea 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,

20 See many statements ‘n the the nests of Italian birds by Eugenie
‘Ornithological Biography.’ See, Bettoni, in the ‘Atti della Soieta
also, some cur.ous observations oa Italiana,’ vol, xi, 1869, p. 487.

Suar XV, Birds—Ceclour and Nidification. 457

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 protec-
tion to the female. Thus all the species in the splendid group
of the Trogons build in holes; and Mr. Gould gives figures” of
both sexes of twenty-five species, in all of which, with one partial
exception, the sexes differ sometimes slightly, sometimes con-
spciuously, in colour,—the males being always finer than the
females, though the latter are likewise beautiful. All thespecies
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.” 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
ditferences, the whole under surface of the male King Lory
(Aprosmictus scapulutus) is scarlet, whilst the throat and chest of
the female is green tinged with red: in the Luphema splendida

21 See his ‘Monograph of the ‘Handbook to the Birds of Aus-
Trogonidz,’ first edition. tralia,’ vol. i. p. 1333 see, also, }p

2 Namely Cyanaleyon. Gould’s 130, 136.

Part II,

458 The Descent of Man.

there is a similar difference, the face and wing-coverts moreover
of the female being of a paler blue than in the male.” In the
family of the tits (Purine), which build concealed nests, the
female of our common blue tomtit (Parus cwruleus) is “much
“less brightly coloured” than the male; andin the magnificent
Sultan yellow tit of India the difference is greater.”

Again in the great group of the woodpeckers,” the sexes are
generally nearly alike, but in the Aleyapicus 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 elimi-
nated. This view is strengthened by what Malherbe states with
respect to Indopicus curlotia ; 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 con-
siderations render this view extremely doubtful: the male takes
a fair share in incubation,”* 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 [have before instanced the Australian parrots, so I may here
instance, without giving any details, the Australian pigeons.”
It deserves especial notice that in all these cases the slight

23 Every gradation of difference
between the sexes may be followed
‘n the parrots of Australia. See
Gould’s ‘ Handbook,’ &c., vol. ii. pp.
14-102.

i4 Maegillivray’s ‘ British Birds,’
voi, ii. p. 433. Jerdon, ‘Birds of
India,’ vol. ii. p. 282.

% All the following facts are

taken from M. Malherbe’s mag-
nificent ‘ Monographie des Picidees,’
1861.

26 Audubon’s ‘ Ornithological Bio-
graphy,’ vol. ii. p. 75; see also the
‘Ibis,’ vol. i. p. 268,

27 Gould’s ‘Handbook to the
Birds of Australia,’ vol. ii. pp 109-
149,

Juav. XV. Birds—Colour and Nidification. 459

differences in plumage between the sexes are of the same general
nature as the occasionally greater differences. A good illustra-
tion 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 differ-
ences 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 differ-
ences 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. Liven 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 be-
tween 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.”*

As far as I can discover there are few large groups of. birds in
which all the species have both sexes alike and_ brilliantly

28 See remarks to this effect in my woik on ‘ Variation under Domestic
eatica,’ vol. i. chap. mi.

460 The Descent of Man. Parr {lL

coloured, but I hear from Mr. Sclater, that this appears to be the
vase with the Musophaga 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 8. America (Cotingide) 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 gene- ,
rally 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.”

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 me/ano-
cephalus and of some allied species, when sufficiently mature to
breed, differ considerably in plumage froin the adult males ; but

2 The ‘ Ibis,’ vol. vi. 1864, p, 122.

unar. XV. Birds—Colour and Nidification. 461

after the second or third moults they differ only in their beaka
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 Pulro pereyrinus ac-
quires her blue plumage more slowly than the male. Mr.
Swinhoe states that with one of the Drongo shrikes (Dicrurus
macrocrreus) 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 strie 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 spoonbill (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 ma!c at a mueh earlier age. The female Bombycilla curolin-
ensts differs very little from the male, but the appendages, which
like beads of red sealing-wax ornament the wing-feathers,”’ are
not developed in her so early in life as in tiemale In the male
of an Indian parrakeet (Paleornis juv mm/cus) 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.

These cases must not be confounded with those where diseased
or old females abnormally assume masculine characters, nor with

30 When the male courts the fe- ‘Ibis,’ vol. vi. 1864, p. 366. On

male, these ornaments are vibrated,
and “are shewn off to great advan-
“tage,” on the outstretched wings:
A. Leith Adams, ‘ Field and Forest
Rambles,’ 1873, p. 153.

41 On Ardetta, Translation of
Cuvier’s ‘Régne 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,
‘This,’ 1863, p. 44, On the Platalea,

the Bombycilla, Audubon’s ‘ Orni-
tholog. Biography,’ vol. i. p. 229.
On the Palzornis, 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. Analo-
gous cases with the females of
Petrocossyphus are given by Mr.
R. B. Sharpe, ‘Proc. Zoolog. Soe.
1872, p. 496.

462 The Descent of Man. Part IL

those where fertile females, whilst young, acquire the characters
of the male, through variation or some unknown cause. 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
fomale; their development foliowing on some slight change in
the elcctive affinities of her cunstituent tissues.

A few words must be added on changes of plumage in relation
{o the season of the year. From reasuns formerly assigned there
can be little doubt that the elegant plumes, long pendant
feathers, cre:ts, &c., of egrets, herons, aod 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 them-
selves. 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
vannot 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 gainec.
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 Gallinacesr,
renders a double moult impossible, for the ptarmigan moults
thrice in the year.= 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.

32 Of these latter cases Mr. Blyth also recorded a similar case (‘ Ornith.
has recorded (Translation of Cuvier’s Biog.’ vol. v. p. 519) with ZLyranga
‘Régne Avimal,’ p. 158) various, estiva.
instances with Lanius, Ruticilla, 33 See Gould’s ‘Birds of Grext
Winaria, and Anas. Audubon has Britain.’

Cuar, XVI. Birds—Inheritance Limited by Age. 403

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 off-
spring 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.

T 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 trans-
mission 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 protec-
tion, of variations which were from the first limited in their
transmission to the female scx. 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.
Binps—concluded,

The immature plumage in relation to the character of the plumage iu
both sexes when adult—Six classes of cases—Sexual differences between
the males of closely-allied or representative species—The female as-
suming 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 im-
portance of the principle of inheritance at corresponding ages
need not here Le 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 betwecn
the young and the old, as far as known to me, may he includal,
it will he well to make a few preliminary remarks.

464 The Descent of Man. Part TU,

With animals of all kinds when the adults differ in colcur
from the young, and the colours of the latter are not, as far as
Wwe can see, of any special service, they may generally be
attributed, like various embryological structures, to the re-
tention 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 aye 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 (Suide), 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 corre-
sponding 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 Gallinaceze, 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
redpole 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 like-
wise the adult state of the common bunting, 2. meiaria. 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 retaincd for life by certain eastern specier

Guar. XVI. Birds --Inheritance Limited by Age. 465

The young of many species of shrikes (Lanius), of some wocd-
peckers, and of an Indian pigeon (Cha/cophaps 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 (Chryso-
coccyx), 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 gevus, Dendrocygna, when mature.'
Similar facts will hereafter be given in regard to certain herons.
Young black grouse (Tetrao tetriz) resemble the young as well
as the old of certain other species, for instance the red grouse
or 7’, scuticus. Finally, as Mr. Blyth, who has attended closely
to this subject, has well remarked, the natural affinitics 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 con-
firms 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 plamage of their remote pro-
genitors, 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 am-
plification. 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

' In regard to thrushes, shrikes, On thrushes, see also Audubon,
and woodpeckers, see Mr. Blyth, in ‘Ornich. Biography,’ vol. ii. p. 195
Charlesworth’s ‘ Mag. of Nat. Hist.’ On Chrysococcyx and Chalcophaps,
vol, i. 1837, p. 304; also foc.note Blyth, as quoted in Jerdon’s ‘ Birds
to his translation of Cuvier’s ‘Rtgne of India,’ vol. iii. p. 485. On Sar-
animal, p. 159. I give the ease kidiornis, Blyth, in ‘ Ibis,” 1807, p
of Loxia on Mr Blyth’s information, 175.

31

406 The Descent of Man. Part TL

to what extent cach rule prevails, I have tabulated the facta
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
thoir parents, it is not meant that they are identically alike,
for their colours are almost always less vivid, and the feathers
sre softer and uften of a different shape.

RULES OR CLASSES OF CASES.

T. 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.

Cuiass J.—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 wil
suffice to call to mind the common pheasant, duck, and house-
sparrow. The cases under this class graduate into others.
Thus the two sexcs when adult may differ so slightly, and the
young so slightly from the adults, that it is doubtful whether

467

Guar. XVI. Birds— Young ike Adult Females.

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, ara
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 ai!
alike; for when in these groups the male does differ from the
female, as with certain parrots, kingfishers, pigeons, &ec., the
young of both sexes resemble the adult female? We see the
same fact exhibited still more clearly in certain anomalous cascs ;
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.? Again, the plumage of the male goos-
ander (Me-gus 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.*

When the young and the females closely resemble each other
and both differ from the males, the most obvious conclusion is

2 See, for instance, Mr. Gould’s
account (‘ Handbook to the Birds of
Australia,’ vol. i. p. 133) of Cyanal-
cyon (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 My. 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.
i. 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 Palzornis rosa, in which the
young are more like the female than
the male. See Audubon (‘ Ornith.
Biograph.’ vol. ii. p. 475) on the
two sexes and the young of Columba
passerina,

5 Lowe this information to Mr,
Gould, who shewed me the speci«
mens; see also his ‘Introduction te
the Trochilida,’ 1861, p. 120.

* Macegillivray, ‘Hist. Brit. Birds,
vol. v. pp. 207-214.

468 The Descent of Man.

Parr {Lh

that the males alone have been modified. Even in the ano-
malous cases of the Heliothrix and Mergus, it is probable that
originally both adult sexes were furnished—the one specics
with a muck elongated tail, and the other with a much elon-
gated 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 re-
markab'e facts recorded by Mr. Blyth,° 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 dis-
tinguished; 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), cer-
tain 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 wag-tails or Motacille.
Mr. Swinhoe® 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

5 See his admirable paper in the
‘Journal of the Asiatic Soc. of
Bengal,’ vol. xix. 1850, p. 223; see

several distinct races, solely by
comparing the adult males.
5 See aiso Mr. Swinhoe, in ‘ Ibis,’

also Jerdon, ‘ Birds of India,’ vol. i.
introduction, p. xxix. ‘a regard to
Tanysiptera, Prof. Schlegel told Mr.
Blyth that he could distinguish

July 1863, p. 131; and a previous
paper, with an extract from a note
by Mr. Blyth, in ‘Ibis,’ Jan. 181,
p. 2a.

Cnar. XVI DBirds—- Young like Adult Females. 469

specics 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
eases 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 wil!
almost always have been exposed to somewhat different con-
tlitions, but we can hardly attribute to this action the mudi-
fication 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 subor-
dinate 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 tc
both sexes.

Although the females of the above closely-allied or repre-
sentative species, together with their young, differ hardly at al)

470 The Descent of Man. Parr IL,

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 Gallinacew: 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 cf
most of the Cotingide, Fringillida, 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 exccption; thus the
females of Parudisea apuda and VP. papuuna differ from each
other more than do their respective males;? 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’ 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?

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
néed 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, &c., we shall see that they differ from one

7 Wallace, ‘The Malay Archi- ‘Ibis,’ 1866, p. 275.
pelago,’ vol. ii, 1869, p. 394. ® ‘Variation of Animats, &e.
8 These species are descr.ved, with under Domestication,’ vol. i. p. 251
yooured figures, by M. F Pollea, ir

Cuar, XVI. Biras-- Young like Adult Females. 471

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.

Tt should be observed that, jn 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, {he female and the
young of the black-grouse ( 7-trao tetrix) resemble pretty closely
both sexes and the young of the red-grouse (1. 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}° 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 the 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
Xess different by the transference in various degrees, of charactcrs
seguired by the males through sexual selection, both during

10 Macgillivray, ‘Hist. British Birds,’ vol. i. pp. 172-174.

472 The Descent of Man. Parr IL.

former and recent times. But it deserves especial attention that
brilliant colours have been transferred much more rarely than
other tints. For instance, the mate of the red-throated blue-
breast (Cyuneculu 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 Gallinacee offer many analogous cases; for none of
the species, such as partridgés, quails, guinea-fowls, &c., 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 Hared
and Cheer pheasants (Crossoptilon auritum and Phasianus wal-
lichit) 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, put would
have been favoured in their rivalry with other maies. Now
variations occurring Jate 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 charac-
ters 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. 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,

N See, on this subject, chap, xaidi. in the ‘Variation of Animals and
Plants ander ~\ mestication.’

Coax. XVI. Berads— Young like Adult kemales. 473

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 moditied
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 elimin-
ated 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-grousa

474 The Descent of Man." Part IT,

and red-grouse serve as a protection? Are partridges, as they
ure 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 in-
stances, 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
atterwards either decreases into a mere circular red line in the
adults of both sexes, or quite disappears in the adult females.”

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 ;
aud that most or all of these variations, owing to the late period
of life at which they appeared, have been from the first trans-
mitted only to the adult male offspring. Any variations in
brightness occurriug in the females or in the young, would have

1% Audubon, ‘ Ornith. Biography,’ aiso the case before given of Indo

vol. i. p. 193. Macgillivray, ‘Hist. gicus carlotia.
Brit. Birds’ vl iii, p 85, See

Cuar. XVI. Birds— Young like Adult Males. 475

been of ne 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 leng
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 unitorm by the free inter-
crossing 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,
30 as to have acquired the same dull coloured plumage.

Cuass IL. When the adult female is more conspicuous than the
adult male, the young of both sexes in their first plumaye 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. Butthe 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," 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 circum-
stance with the Gallinacese. In most of the species the female is
more distinctly coloured and brighter than the male,“ but in
some few species the sexes are alike. In 7urnix 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
sertainly much more pugnacious than the male; so that the

13 ¢Westminster Review,’ July, 178, 180, 186, and 188. In the
1867, and A. Murray, ‘Journal of British Museum specimens of the
Travel,’ 1868, p. 83. Australian Plain-wanderer (Pedio-

14 For the Australian species, see mnomus torquatus) may be seen,
Gould’s ‘ Handbook,’ &c., vol. ii. pp. shewing similar sexual differences,

470 Lhe Descent of Man. Pant ll

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.® Mr. Blyth believes, thet the
young of both sexes resemble the adult male.

The females of the three species of Painted Snipes (Rhynchea,
fig. 62) “are not only larger bunt much more richly coloured than
“ the males.” 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 Riynchaa australis
it is simple in the male, whilst in the female it makes four
distinct convolutions before entering the lungs.‘7 The female
therefore of this species has aequired an eminently masculine
character. Mr. Blyth ascertained, by examining many speci-
mens, that the trachea is not convoluted in either sex of FP.
bengalensis, which species resembles £. 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 differ-
ences relate to the female sex. The young of both sexes of #.
bengalensis in their first plumage are said to resemble the
mature male. There is also reason to believe that the male
undertakes the duty of incubation, for Mr. Swinhoe” found the
females before the close of the summer associated in flocks, as
occurs with the females of the Turnix.

The females of Phalaropus fulicurius and P. hyperboreus ace
larger, and in their summer plumage “ more gaily attired than

the males.” But the difference in colour between the sexes is
far frou conspicuous. Accoiding to Professor Steenstrup, the

8 Jerdon, ‘Birds of India,’ vol. ” Gould’s ‘Handbook to the
iit. p. 596. Mr. Swinhoe, in ‘Ikis,’ Birds of Australia,’ vol. ii. p. 275.
1865, p. 542; 1866, pp. 131, 405. 18 «The Indian Field,’ Sept. 1858,

** Jerdon, ‘Birds of India, vol. p 3.
‘id. p. 677. 1 «This, 1896, p 298.

Cuap. XVI.

Birds— Young lire Adult Males.

477

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 (Hudro-

mias ormellus) is larger than the male, and has the red and

Pig. v2.

WA

Rbynvhea capensis (from Brehm).

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

I have not been

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

178 The Descent of Man. Vaur I,

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 guleatus) would be thought by any one
to be the female, from his smaller size and from the appendages
ai:d 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.” The female is said by Mr. T. W.
Wood ” 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
(Promeeus irrorutus) 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 gere-
* rally comes off conqueror.” 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

it 1s, as he informs me, with Limosa
fapponica and some few other
Waders, in which the females are
luryer and have more strongly con-
trasted colours than the males,
21 ‘The natives of Ceram (Wallace,
Malay Archipelago,’ vol. ii. p. 150)
gssert that the male and female sit
sternately on the eggs; but this

assertion, as Mr. Bartlett thinks,
may be accounted for by the female
visiting the nest to lay her eggs.

22 <The Student,’ April, 1870, p.
124,

28 See the excellent account of
the habits of this bird under confine-
ment, by Mr. A. W. Bennett, in ‘ Land
and Water,’ May, 1868, p. 233.

Suap, XVI,

Bivds— Young like Adult Males. 479

plumes with more strongly contrasted colours; nevertheless he
undertakes the whole duty of incubation.

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, ra-
“ diated, 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.” *

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 differ-
ence, 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

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
ot Rhea. .

25 For the Milvago, see ‘Zoology
of the Voyage of the Beagle,”
Birds, 1841, p. 16. For the Climac-
teris. and night-jar (Eurostopodus),
see Gould’s ‘ Handbook to the Birds
:f Australia,’ vol. i. pp. 602 and 97.
fhe New Zealand shieldrake (7Za-
dorna variegata) offers a quite ano-
malous case ; the head of the female
‘s 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 fea-
thers, 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 (‘ Proce. Zool. Soc.’
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.

.480 The Descent of Man. Parr [T,

males in the last class, My. 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.” *®—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, a8 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 ex-
cited 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 attrac-
tions of the females; the males and the young being left not at
all, or but little modified.

Cuass III. When the adult male resembles the adult female, the
young of both sexes have a peeuliur 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 pluwage. The male and female of the splendid

2 Jerdon, ‘ Birds of india,’ vol. iii, p. 598,

cnar, XVI. Birds—Young tike both Adults. 481

scarlet ibis are alike, whilst the young are brown; and the
scarlet-colour, though common to both sexes, is apparently a
scxual 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
bas a nuptial character. Young swans are slate-coloured,
whilst the mature birds are pure white; but it would he
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.
Crass IV. When the adult male resembles the adult femule, tne
youny of both sexes in their first plumage resemble the udults.—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,””—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 parro-
keets (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* 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.”

27 Jerdon. ‘ Birds of India,’ vol. i. 28 Gould, Ibid. vol. ii. pp. 37, 46,
pn. 222, 228. Gould’s ‘Handbook to 56,
the birds of Australia,’ vol. i. pp. * Audubon, ‘Ornith, Biography,
124, 130. ie vol. ii, p. 50,

©

482 The Descent of Man. Parr i,

I may remark before proceeding that, under the present and
next two classes of cases, the facts are so complex and the con-
clusions 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 birda
in the present class, can rarely or never be of service to them as a pro-
tection ; so that they have probably been gained by the males through
s xual selection, and then transferred to the females aud 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 malvs 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
b.anty. Exactly the reverse occurs under nature; for, in almost every
large group in which the sexes generally resemble each other, the
niales of some few species are in a slight degree more brightly eoloured
than the females. It is again possible that the females may have
selected the mvure 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, owiny 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 thioughout the animal kingdom, that is, on the males;
and that these have transmitted their gradually-acquired colvurs,
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 wales 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 m 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.*°
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.* 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 brvod of four, which were born pure white. These young birdy

30 ¢Variation of Animals and *! Charlesworths’ ‘Mag. of Nat
Plants under Domestication ’ vol. ix. Hi.’ vol. i. 1837, pp. 305, 306.
p 79

onar, XVI Birds-- Young like both Adults.

483

were not albinoes, as shewn by the colour 9f their beaks und legs, whic bh
aearly resembled the same parts in the adults.5*

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 In the
house-sparrow (P. domesticus) the male differs much from the female
and from the young. ‘Ihe young and the females are alike, and
resemble to a large extent buth sexes and the young of the sparrow af
Palestine (P. brachydactylus), as well as of some allied species. Wi
raay 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 resembie the male of the house-sparrow; so that they have all
been moditied in the same manner, aud all depart trom the typ:cal
colonring of their early progenitor. This may have b-en effected by
a male ancestor of the tree-sparrow having ‘varied, firstly, woen 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 ol 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 tueir 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 fur
the period of variation in birds has generally determined the transmis-
sion of characters to one sex or to both. The two rules, often referred
to ore that variations occurring late in life are transmitted to one
and the same sex, whilst those which occur early in life are transwitted
to both sexes), apparently hold good in the first,*4 second, and fourth
classes of cases; but they fail in the third, often in the fifth,®* and in
the sixth small class. They apply, however, as far as | can judge, to
e considerable majority of the species; and we must not forget the
striking generalisation by Dr, W. Marshall with respect to the protu-
berances on the heads of birds. Whcther or not the two rules generally

32 ¢ Bulletin de la Soc. Vaudvise Audubon, ‘ Ornith. Biography,’ vol.

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).

33 T am indebted to Mr. Blyth
for information in regard to this
genus. ‘The sparrow of Palestine
belongs to the sub-genus Petronia.

34 For instance, the males of
Tanagra estiva and Fringilla cyanea
reyuire three years, the male of
Fringilla eiris tour years, to cori-
plete their beautiful piumage. (See

i p. 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
ear.

36 Thus the Zbis tantalus and Grus
americanus take four years, tha
Flamingo several years, and the
Ardea ludovicana two years, before
they acquire their pertect plumage.
See Audubon, ibid. vol. i. p 221;
vol. iii, pp. 135, 139, 211.

The Descent of Man. Paur Il

184

hold good, we may concluJe from the facts given in the eighth chapter,
that the period of variation is one important clement in determining the
form of transmission.

With birds it is difficult to decide by what standard we ought tn 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 muults throuzh which the species passes, The
mouiting of birds, even wthin the same family, sometimes diff rs
much without any assignable cause, Some birls moult so erly, that
nearly all the body feathers: are cast off before the first wing-feath: rs
are fully grown; and we cannot believe that this was the primordial
state uf 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. Th's may be
illustrited by the practice followeil by some bird-fanciers, who pull
out a few feathers from the bri ast of nestling bullfiuches, an 1 frum the
head or neck of young gold-pheasants, in order to ascertaiu their scx ;
for in the males, these feathers are immediately replaced by culoured
ones.3 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 remark-
able fact that various birds occasionally breed whilst retaining their
immature plumaye.’’

The fact of birds breeding in their immature plumage seems opposed
tu the belief that sexual selection has played as impvrtant a part, as I
believe it his, in giving ornamental colours, plumes, &c., to the males,
and, by means of equul transmission, to the females of many specics.
The objection would be a valid one, if the younger and less ornamented
mules were as successful in winning females and propigating 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 tuntalus as a rare event, as dues Mr.
Swinhoe, in regard to the immature males of Oriolus.** If the young
of any species in their immature plumage were more successful in
winning partuers than the adults, the adult plumage would probably

36 Mr. Blyth, in Charlesworth’s
‘Mag. of Nat. Hist.’ vol. i. 1837, p.
300. Mr. Bartlett has informed
me in regard to gold-pheasants.

37 I have noticed the following
eases in Audubon’s ‘Ornith. Bio-
graphy.’ The redstart of America,
(Muscapica ruticilla, vol. i. p. 203).
The Ibis tantalus takes four years to
come to full maturity, but some-
times breeds in the second year (vol.
vii, p. 133), The Grus americanus
takes the same time, but breeds
before acquiring its full plumage
(vol. iii, p. 211). The adults of
Ardea cerulea are kiue, and the
young white; and white, mottled,
aad mature blue birds may all be
asen breeding together (vol. iv. p.

58): but Mr. Blyth informs ime
that certain herons apparently are
dimorphic, for white and coloured
individuals of the same age may be
observed. The Harlequin duck
(Anas histrionica, Linon.) 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 leucoce-
phalus, vol. iii, p. 210) is likewise
known to breed in its immature
state. Some species of Oriolus (ac-
cording to Mr. Blyth and Mr.
Swinhoe, in ‘Ibis,’ July 1863, p,
68) likewise breed before they
attain their full plumage.

38 See the last foot-note.

Unar, XVI, Birds— Young like both Adults. 485

avon be lost, as the males would prevail, which rm tained their immature
dress for the longest peried, and thas the chaructcr of the specica
would ultimy ¢ ly be modified.2? If, on the other hand, the young never
succe ded in obtaining a female, *be habit of early reproduction would
prhisps be sooner or later eliminated, trum being superiluous aud
entailing waste of power.

The plumage of ceitain birds goes on increasing in beauty during
many yoars atter they are fully mature; this is the :as¢ with ihe train
ef the peacovk, with some of the birds of paradise, and with the crest
und plumes of certain heions, for smstance, the Ardea ludovicana.'*
but it is doubtful whether the continued development of such teathers
is the result of the selection of successive beneficial vari.tious (though
t isis the most probable view with birds of paradise) or merely of cun-
timuous growth. Most fishes continue increasing in size, as long us tley
are in gond health und have plenty of food: und a somewhat similar
law may p evail with the plumes of birds.

Cras 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 res:mble 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 muy
differ greatly from the adults in both thetr seasonal plumages.—The eases
in this class are singularly complex; nor is this surprising, as they
depend on inhcritance, limited in a greater or less degree in three
different ways, namely, by sex, age, aud the season of the year. In
some cases the individuals of the same species pass through at least
tive distinct states of plumage. With the species, in which the mate
ditfers from the female during the summer scason alone, or, which is
rarer, durng both 8 asons,‘! the young generuly resemble the females,
—as with the so-called goldfinch of North America, and apparently
with the splendid Maluri of Australix.4? With chose species, the sexes
of which are alike during both the sumer aud wiuter, the youug may

3° Other animals, belonging to © Jerdon, ‘Birds of India,’ vol.
quite distinct classes, are either iii. p. 507, on the peacock. Dr.
habitually or occasionally capable Marshall, thinks that the older and

of breeding before they have fully
acquired, their adult characters.
This is the case with the young
males of the salmon. Several am-
phibians have been known to breed
whilst retaining their larval struc-
ture. Fritz Miiller has shewn
(‘ Facts and Arguments for Darwin,’
Eng. trans. 1869, p. 79) that the
males of several amphipod crusta-
ceans 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
fucts are highly interesting, as
tearing on one means by whieh
species may undergo great modifi-
gations of character.

more brilliant males of birds of
paradise, have an advantage over
the younger males; see ‘Archives
Néerlandaises,’ tom. vi, 1871.—On
Ardea, Audubon, ibid. vol. iii. p.
139.

‘4 Foy illustrative cases see vol.
iv. of Macgillivray’s ‘Hist. Brit.
Birds ;’ on Tringa, &c., pp. 229, 271;
on the Mache‘es, p. 172; on the
Charadrius hiaticula, p. 118; on the
Charadrius pluvialis, p. 94.

‘4? For the goldfinch of N. America,
Fringilla tristis, Linn., see Auduben.
‘Ornith. Biography,’ vol. i. p. 172.
For the Maluri, Gould’s ‘ Hanitboop
te the Birds of Australia,’ vol. i. p
318.

486 The Descent of Man. Parr IL

resemble the adults, firstly, in their winter dress; secondly, and this ia
of much rarer ocenrrenee, in their summer dress; thirdly, they may be
intermediate between these two states; and, fourthly, they may cliffer
greatly from the adults at all seasons, We have an instance of the
firot of these four cvas.s in one of the egrets of India (Buphus core-
mandus), in which the young and the adults of both sexes are white
during the winter, the adults becoming yolden-buff during the summer.
With the gaper ( Anastomus oscitans) of India we have a similar case,
but the coluurs are reversed; for the young and tue adults uf both
sexes ure grey and black during the winter, the adults becuuing white
during the summer.#? As an instance of the second case, the young vi
the razor-biil (Alea 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 leucnphrys), a8 soon
as fledged, have elegant white stripes on their heads, which are lost by
the young and the old during the winter.** With respect to the third
case, namely, that of the young having an intermcdiate character between
the summer and winter adult plumages, Yarrell** insists that this
occurs with many waders. Lastly, in regard to the young differing
greatly from boti sexes in their adult summer and winter plumayes,
this oveurs with some herons aud 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 ditt r from those given under
Classes I. and LIL. only iu the charactvrs originally acquired by the
males during the brecding-season, having been lim ted in their trans-
mission to the corresponding season. When th» 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 plumaze; we can account by
sexual selection for the summer or nuptial plumage of the adults, but
low are we to account for their distinet winter plumage? If we coui.l
admit that this plumage serves in all cases as a protection, its ac-
quirement would be a simple affair; but there seems no guod reason
tor this admission. It may be suggested that tue widely different
conditions of life during the winter and summer have acted in a direct
manner on the planage; this may have hud some effect, but I have
uot 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, paitially movlified
through the tranafvrence of some characters from the summer plumag.:,
has been retained by the adults during the winter. Finully, all ihe
cases in our present cliss apparently depend on characters acquired hy
the adult males, having been variously limited in their transmission
according to age, season, and sex; but it would not be worth while ww
attempt to follow oul these ermplex relations.

43 Tam indebted to Mr. Blyth On the Fringilla leucophr,s, Au-
for information as to the Buphus; dubon, ibid. vol. ii. p. 89. I shall
see also Jerdoa, ‘Birds of India,’ have hereafter to refer to the young
vol. iii. p. 749. On the Anastomus, of certain herons and egrets being
see Blyth, in ‘ Ibis,’ 1867, p. 173. white. ;

“! On the Alca, see Macgillivray, 43 ¢ History of British Birds,’ vel

Uist. Brit. Birds,’ vol. v. v. 347. 1. 1839, p. 159

Cuav. XVI. Birds— Young like both Adults.

487

Crass VL. The young in their first plumage differ from each «ther
according to sea ; the young males resembling more or less closely the aduli
males, and the young females more or less closely the adult females.—
The cages in the present class, though occurring in various groups, ara
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 blackeap
(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
ean be distinguished by this character even as nestlings. In the family
of thrushes an unusual number of similar cases have been noticed ; thus,
tle male blackbird (Turdus merula) can be distinguished in the nest
from the female. The two sexes of the mocking bird (T'urdus polyglottus,
Linn.) differ very little from each other, yet the males van easily be
distinguished at a very ewly age from the females by shewing mure
pure white.® The majes ot » forest-thrush aud of a rock-thrush
(Orocetes erythrogastra and Petrocinela cyanea) bave much of their
plumage of a fine blue, whilst the f-males are brown; an.1 the nestling
males of both spceivs have tueir main wing and tail-feathers edged witn
blue, whilst thuse of the femule are edged with brown.” In the young
blackbird the wing feathers assume tli ir mature character and becume
black after the others ; ou the other han |, in the two species just named
the wing-feathers become blue before tle others. The most probable
view with reference tu the cases in the present class is that the males,
ditfereutly from what occurs in Class [., have transmitted thcir colours
to their male offspring at an earlier age than that ut which they were
first acquired; for, if the males hud varied whilst quite ycung, thcir
characters would probably have been transmitted to both sexes.*®

Iu Atlhurus polytmus, a humming-bird, the male is splendidly coloured
blick ind green, and two of the tail-feathers are immensely lengthened ;
the fenale 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 culcurs proper
to their sex, and their tail-feath-1s soon become elongated. I owe this
information to Mr. Gould, whv has given me the following more striking
and ay yet unpublished case. Two humming-birds belonging to the
genus Eustephanus, both beautifully coloured, inhabit the smal). island
of Juan Fernandez, and have ulways been ranked as specifically dis-
tinct. But it has lately been ascertained that the one, which is of a
rich chesnut brown colour with a golden-red head, is thie male, whilst
the otter, which is elegantly variegated with green and white with a
mctallic-green head is the female. Now the young frum the iret

46 Audubon, ‘ Ornith. Biography,’
vol. i. p. 113.

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 Charles-
worth’s ‘Mag. of Nat. History,’ vol.
i. 1837, p. 113.

48 The following additional cases
may be mentioned ; the young males
of Tanagra rubra can be distinguished
trom the young females (Audubon,

‘Ornith. Biography,’ vol. iv. p. 392),
and so it is with the nestlings of a
blue nuthatch, Dendrophila frontalis
of India (Jerdon, ‘ Birds of India,’
vol. i. p. 359). Mr. Blyth also
informs me that the sexes of the
stonechat, Samicola rubicola, are
distinguishable at a very early age.
Mr. Salvin gives (‘Proc, Zoolog. Soe.’
1870, p. 206), the case of a hum-
ming-bird, like the tollowirg one 2f
Eustephanus,

488 The Descent of Man. Farr IJ

somewhat resenible 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 soul appear that both sexes have been reudered
beautiful indepenently; aud not that one sex las partially transferred
its beauty to the other. The m-l. 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 Ruynchea or Turnix in our second
class of cases. But there is wuch difficulty in understanding how this
could have been effected at the same time with the two sexes of the
same species. Mr. Sulvin states, as we have seen in the eighth chapter,
that with certvin humming-tirds the males greatly exceed the females
in number, whilst with other species inhabiting the same country the
females greatly excecd 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 pamber, but that during
another lenzthened period the females had fur eaceeded the males, we
eould understand how the males at one tine, and the females at
another, mizht have been rendcred beautiful by the selection of the
brizhter-coloured individuals of either sex; both sexes transmitting
their characters to their young at a rather earlier »ge than usuial.
Whether this is the true explanation I will not pretend to say; but the
case is too remarkable to be passed over witt.out 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

Unar. XVI. Birds—Colour and Protzction. 489

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 briyht-coloured, and as these
form whole 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 relution 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 over-
heard. Mr. Wallace remarks * 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. Wood-
peckers 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-pro-
nounced 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 seea 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 quad-
rupeds, 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.

49 ¢ Westminster Review,’ July, 1867, p. 5.

490 The Descent of Man. Pars TI,

"colonr.”* Calling to my recollection the desert-birds of South
Americu, 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
specics belonging to fifteen genera, which manifestly have their
plumage coloured in a protective manner; and this cvlouriny 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 pro-
tected, 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-billcd birds,
especially those which frequent reeds or sedges, are obscurely
coloured. No doubt if their colours had been brilliant, they
would haye 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 gaine@ through sexual
selection, from being attractive. Many of the soft-billed birds
are songsters; and a discussion in a former chapter should not

80 ¢ This,” 1859, vol. .. p. 429, e¢ his experience of the Sahara, this
seq, Dr. Rohlfs, however, remarks statement is tuo strong.

" 9 5
to me in a letter that, according to

Vaar. XVI. Lirds—-Conspicuous Colours. 4g!

be forgotten, in which it was shewn that the best songstcrs are
rarely ornamented with bright tints. It would appcar 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 spec‘es, 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 sclection 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 neai'ly the same thing,
to attribute the result to the direct action of the conditions of life.

Both scxes 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 «tra), 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 prolable 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 of 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 black-cock and capercailzie, in
the brightly and variously coloured beak of the scoter-drake
(Oidemia), in the red beak of the chough (Corvus yraculus, Linn.).
of the black swan, and the black stork. ‘his 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.” The naked skin, also, at the base of the

51 No satisfactory explanation has size, and still less of the bright
sver been offerad of the immense colours, cf the toucan’s beak. Mr

42 Part IJ.

The Descent of Man.

beak and round the eyes is likewise often brilliantly coloured ;
and Mr. Gould, in speaking of one species,” says that the colours
of the beak “ are doubtless in the finest and most brilliant state
“ during the time of pairing.’ There isno 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 ue
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 (Berniclu anturctica), the silver-pheasant, &c.,
whilst the females are brown or obscurely mottled. Therefore,
on the same principle as before, it is probable that both sexes of
many hirds, such as white cockatoos, several egrets with their
beautiful plumes, certain ibises, gulls, terns, &c., 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, &c., 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 oscituns, 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 imma-
ture state, and the adults in their winter dress, being grey and
black. With many kinds of gulls (Larus), the hoad and neck
become pure white during the summer, being grey or mottled
during the winter and in the young state, On the other hand,

Bates (‘The Naturalist on the
Amazons,’ vol. ii. 1863, p. 341)

by its breadth, depth, as well as
length, is not intelligible on the

states that they use their beaks for
reaching fruit at the extreme tips
of the branches; and likewise, as
stated by other authors, for ex-
tracting eggs and young birds from
the nests of other birds. But, as
Mr. Bates admits, the beak “can
scarcely be considered a very per-
“fectly-formed instrument for the
“end to which it is applied.” The
great bulk of the beak, as shewn

view, that it serves merely as an
organ of prehension, Mr. Belt
believes (‘The Naturalist in Nicae
ragua,’ 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.

52 Ramphastos carinatus, Gould’s
‘Monograph of Ramphastida.’

Cuap. XVI.

493

Birds— Conspicuous Colours.

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.

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.* 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 indi-
viduals 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 cap 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

53 On Larus, Gavia, and Sterna,
see Macgillivray, ‘ Hist. Brit. Birds,’
vol. v. p. 515, 584, 626. On the
Anser hyperboreus, Audubon, ‘ Or-
nith, Biography,’ vol. iv. p. 562.
On the Anastomus, Mr. Blyth, in
Ibis,’ 1867, p. 173.

54 Jt may be noticed that with
eultures, 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.

The Descent of Man.

Part tI.

494

parts of a purer white, and the variously coloured daik 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
fome 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
roscate instead of a plum-blue head. 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 appre-
ciated 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 adulis 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,5> 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
eould look still further back to the still earlier progenitors of
these two species, we should“probably see the adults dark-

55 See Jerdon on the genus specific names. Audubon (‘Ornith.

Palaornis, ‘Birds of India,’ vol. i.
p. 258-260.

56 The young of Ardea rufescens
end A. cerulea of the U. States are
likewise white. the adults being
soloured in accordance with theit

Biography,’ vol. iii. p. 4165 vol. iv.
p. 58) seems rather pleased at the
thought that this remarkable change
of plumage will greatly “ disconceit
“ the systematists.”

Onar, XVL. Birds— Novelty admired. 495

coloured. J infer that this would be the caso, 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 Ai dew
gularis, the colours of which are the reverse of those of 4. ushu,
for the young are dark-coloured and the adults white, the young
having retained a former state of plumage. It appears there-
fore that, during a long line of descent, the adult progeritors
of the Ardea asha, the Buphus, and of some allies, have under-
gone 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
fur 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 con-
sequently that no permanent effect could be produced. We may
admit that taste is fluctuating, but itis not quite arbitrary. It
depends much on habit, as we see in mankind; and we may
inter 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 ina 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, &c.; 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
ina 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
pirds do not commonly get partners in marriage; and that the
4lack ravens of the Feroe Islands chase away their piebald
brethren. But this dislike of a sudden change would not

496 The Descent of Man. Parr IL

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 ro improbability in animals
admiring for a very long period the same general style of ornamen-
tation or other attractions, and yet appreciating slight changes
in colours, form, or sound.

Summury of the Four Chapters on Birds——Most male birds ara
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 ditfer 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 ornameutal 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 tothe best ef ect; 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. ‘lo 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 ataste for the beautiful.
The females, moreover, are known occasionally to exhibit a
marked preference or antipathy for certain individual males.

Tf it be admitted that the females prefer, or are unconsciously

Cuap, XVI, Birds—Summary. 497

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 ore
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 imme-
diately 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 grada-
tions, 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
oeelli 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, &c., 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 hava
inherited all characters in common they necessarily resemble
each other; but as the successive variations may be differently

33

498 The Descent of Man. Pas af

transmitted, every possible gradation may be found, even within
the same genus, from the ciosest similarity to the widest dis-
similarity 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. ‘he indi-
viduals 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.

Jn 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 quarrel-
some 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 .nales,
we can understand how it is that they have gradually been
rendered, by sexual selection and sexually-limited transmission,
more beautiful than tne males—the latter being left unmodified
or only slightly modified.

Whenever the caw of inheritance at corresponding ages prevails

Cuap, XVI. Birds— Summary 499

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
vther 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; con-
sequently 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 pre-
served 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 batile,
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
inhoritance—the females and the young being left comparatively
but little modified.”

5¢ J am greatly indebted to the birds, and the two following ones
cindness of Mr. Sclater for having on mammals. In this way I have
woked over these fuur chapters on been saved from making mistakes

500 The Descent of Man. Pagy UL

CHAPTER XVII.
SrconDAny SexuanL CHaracTEers oF MAMMALS,

The law of battle—Special weapons, confined to the males—Cause o.
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 detence—On the
preference shewn by either sex in the pairing of quadrupeds.

Wirth 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.”!_ I observed the same
fact with the hides of the guanacoes in Patagonia; and on one
oceasion 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?

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 autho-
tities.

' See Waterton’s account of two
hares fignting, ‘ Zoologist, vol. i,
1843, p. 211. On moles, Bell,
‘Hist. of British Quadrepeds,’ Ist
edit. p. 100. On x,uir1els, Audubon

and Bachman, ‘Viviparous Quad-
rupeds of N. America,’ 1846, p. 269.
On beavers, Mr. A. H. Green, in
‘Journal of Lin. Soc. Zoolog.’ vol. a.
1869, p. 362.

2 On the battles of seals, see Capt.
C. Abbott in ‘ Proc. Zool. Soc.’ 1866,
p. 191; also 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, tn ‘ Pro
Zool. Soc.” 1867, p. 246.

Cnar. XVII. = Mammals—Law of Battle. 501

11 male animals which are furnished with special weapons
for fighting, are well known to engage in fierce battles. Tha
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? 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 descen-
dants, 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 J. B. Sulivan informs me that, when hé lived in-the—Fatk=-
land 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
ease is very different with the males of many other animals.
We sce this in the horns of stags and of certain kinds of

3 See Scrope (‘ Art of Deer-stalk- wapiti, moose, and rein-deer have
ag,’ p. 17) on the locking of the been found thus locked together.
horns with the Cervus elaphus. Sir A. Smith found at the Cape of
Richardson, in ‘Fauna Bor. Ameri- Good Hop2 the skeletons cf twe
cana,’ 1829, p. 252, says that the gnus in the same condition.

502 The Descent of Man. Pare Il,

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. In the male
elephant of India and in the male dugong® the upper incisora
form offensive weapons. In the male narwhal the left canine
alone is developed into the well-known, spirally-twisted, so-
ealled horn, which is sometimes from nine to ten feet in length.
It is believed that the males use these horns for fighting to-
gether; for “an unbroken one can rarely be got. and ocvasionally
* one may be found with the point of another jammed into the
“ broken place.”® 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 pro-
vided with a remarkable apparatus, namely a spur on the foreleg,
closely resembling the poison-fang of a venomous snake; but ac-
cording 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.’

When the males are provided with weapons which in the
females are absent, there can hardly be 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

4 Mr, Lamont (‘Seasons with the ® Mr. R. Brown, in ‘ Proc. Zool.

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.
Oc the ocvasional absence of the
tusks in the female, see Mr. R.
Brown, ‘Proc. Zool. See.’ 1868, p.
$29,

? Owen, ‘Anatome of Vertebrates,’
vol. iii, p. 283,

Soc.” 1869, p. 553, See Prof. Turner,
iu 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 ‘Proc. Zaclog. Soc.’ 1&71,
p. 42.

7 Owen on the cachalot and
Ornithorhynchus, ibid. vol. iii pp.
638, 641. Harting is quoted by Dr.
Zonteveen in the Dutch translat, of
this work, vol. ii, p. 292.

Cuar. XVI. = Mammals—Law of Battle. 503

purposes, more especially as a defence against their encmics, it
is a surprising fact that they are so poorly developed, or quite
absent, in the females of so many animals. With female deez
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 thia
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 some-
times 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 pro-
genitur 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?

The horns of the remdeer are developed at a most unusually

® On the structure and shedding regard to the American variety or
of the horns of the reindeer, Hoff- species; also Major W. Ross King,
berg, ‘Ameenitates Acad.’ vol. iv. ‘The Sportsman in Canada,’ 1866,
1788, p. 149. See Richardson, }. 80.

Fauna Bor. Americana, p. 241, in

The Descent of Man. Par IL

304

sarly age; but what the cause of this may be is not known.
The effect has apparently been the transference of the horns to
beth 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.® Moreover the females of some other species of decr
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 pro-
* tuberance in the place of the horn.” 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 un-
known cause at an unusually early age in the males, and thcir
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 )—to those which
have fairly developed horns, but manifestly smaller and thinner
than in the male and sometimes of a different shape,’—and
ending with those in which both sexes have horns of equal size.
As with the reindeer, so with antelopes there exists, as pre-
viously 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 in inheritance. It accords with this

* Isidore Geoffroy St. Hilaire,
‘Essais de Zoolog. Générale,’ 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 Ba-
varia,’ 1860, 2nd edit. 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 Fucks.”

“ On the Cervelus, 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 Acad.
of Nat. Sciences,’ May, 1868, p. 9.

Tam indebted to Dr. Canfield,
for this information, see also his
paper in ‘Proc. Zoolog. Soc.,’ 1866,
p. 105.

2 For instance the horns of the
female Ant. euchore resemble those
of a distinct species, viz. the Aut.
doreas var. Corine, see Desmarcst,
‘Mammulogie,’ p. 423,

Cnar,. XV. AZammals—Law of Battle. 505

view that even in the same restricted genus both sexes of some
species, and the males alone of others, are thus provided- It is
tlso @ remarkable fact that, although the females of Antilope
bezeartica 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.’ 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 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 con-
siderably 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 mascuiine 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. 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 sonduicus) 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 aud
“ 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.”" Dr. Forsyth Major
also informs me that a fossil skull, believed to be that of the
female Bos etruscus, has been found in the 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

13 Gray, ‘Catalogue Mamm, Brit. ricana,’ p. 278.
Mus.” part iii, 1852, p. 160. ‘8 ¢Land and Water, 1837, p
* Richardson, ‘Fauna Bor, Ame- 346,

506 The Descent of Man. Past IL

are said to be shorter in the female. 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 pos-
session of horns by both sexes, seems at first to prove that the
horns in this species do not constitute a sexual character ;” 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
Iam informed that with Welch sheep the horns of the males are
considerably reduced by castration; but the degree depends
wuch on the age at which the operation is performed, as is like-
wise 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.”#* 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 desti-
tute 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 re-
semble them. The Antilope bezoartica offers a somewhat ana-
logous 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

'6 Sir Andrew Smith, ‘ Zoology
of 8. Africa,’ pl. xix. Owen, ‘ Ana-
tomy of Vertebrates,’ vol. iii. p. 624.

7 This is the conclusion of
Seidlitz, ‘Die Darwinsche Theorie,’
1871, p. 47.

18 | am much obliged to Prof.
Victor Carus, for hiving maue en-

quiries for me in Saxony on this
subject. H. von Nathusius (‘ Viet
zucht,’ 1872, p. 64) says that tis
horns of sheep castrated at an early
period, either altogether disappear
or remain as mete rudiments; but
I do not know wheth«r he refere
to merinos or to erdinuw sy treads.

Unarp. XVII = Mammals—Law of Battle. 507

condition of the horns in some early progenitor of each species.
But why castration should lead to the reappearance of an early
sondition of the horns cannot be explained with any certainty
Nevertheless, it seems probable, that in nearly the same manncr
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 ;’° 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,
ditfer 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 ky some as a distinct species,
and here “not one in a hundred is found with tusks, the few
“that possess them being exclusively males.” 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 m
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 fari-
naceous 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” with

1@ T have given various experi- 20 Sir J. Emerson Tennent, ‘ Cey-
ments and other evidence proving lon,’ 1859, vol. ii. p. 274. For
that this is the cave,» my ‘Varia- Malacca, ‘Journal of {ndian Archi-
ticu of Animals and Plants under pelago,’ vol. iv. p. 357,

Domestication,’ vol. 1i., 1868, pp. 39 21 ‘Calcutta Journal of Nat. Hist
wh. vol, ii, 1845, p. 526,

508 Lhe Descent of Man. Par UI,

the wild goat (Capra xgagrus) 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 power-
ful man knocked over like a child. Goats and certain species of
sheep, for instance the Ovis cycloceros of Afghanistan,” 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 0. cycluceros 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. 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. My. 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
thrast 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

2 Mr. Blyth, in ‘ Land and goats see the ‘Field,’ 1869, p. 150.
Water,’ March, 1867, p. 134, on 23M. E. M. Bailly, ‘Sur l’usage

the authority of Capt. Hutton and des Cornes,’ &e, ‘Annal. des Se
others. For the wild Pembrokeshire Nat.’ tom. ii. 1824, p. 369.

Cuar. XVII. Mammals—Law of Battle. 509

force, that I have seen a hard plank deeply indented by a single
blow.

With antelopes it is sometimes difficult to imagine how they
can possibly use their curiously-shaped horns; thus the spring-
boc (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
snegests that they would inflict a fearful wound down each side
of the face of an antagonist. The slightly-curved horns of the

Fig. 63. Oryx leucoryx, male (from the Knowsley Menagerie).

Oryx leucoryx (fig. 68) 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 com-
batants 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 mancenvre. It has been
recorded that one of these antelopes has used his horns with
effect even against a lion; yet from being forced to place his
head between the fore-legs in order to bring the points of tne

510

The Descent of Man. Part IL,

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 pculiar position, asa 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 down-
wards, as is now done by certain stags; and itis 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 eluphus), 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’ 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,*® 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. MeNeill 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

24 On the horns of red-deer, Acad. of Nat. Science,’ May, 1868,

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 Moritzkurg case.

#2 Hon, J. D. Caton (‘Ottawa

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 usage
des Cornes,’ ‘Annales des Sc. Nat.
tom. ii, 1824, p. 371.

Gnar. XVIL = Mammals—Law of Battle. S11

used in attack. Sir Philip Egerton also informs me both as to
ted-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 rovnd, 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; whén a man was attacked by a
wapiti deer (Cervus cunmidensis) 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 ayainst 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 hy this procedure gradually drove the
party of rescuers backwards, to a distance of 150 or 2U0 feet;
and the attacked man was killed.”

Although the horns of stags are efficient weapons, there can,
I think be no doubt that a single point would have been muck
more dangerous than a branched antler; and Judge Caton, who
has had large experience with deer, fully concurs in this conclu-
sion. 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 partas 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 1
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
Statesare now being modified through sexual and natural selection.
A writer in an excellent‘ American Journal” says, that he has

*5 Sea a most interesting account 27 <The American Naturanes,
nm the Appendix to Hon. J. D. Dec. 1869, p, 552.
Caton’s paper, as above quoted.

512 Lhe Descent of Man. Part Wl.

hunted for the last twenty-one yearsiu the Adirondacks, where
the Corvus 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,

,
Fig. 64. Strepsiceros Kudu (from Sir Andrew Smith’s ‘ Zoology of South Africa’).

“ it consists of a single spike, more slender than the antler, and
* scarcely half so long, projecting forward from the brow, and
* tovpminating in a very sharp point. Jt gives a considerable

boa

Omar. XVI =Mammals—Law of Battle. 513

“ 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 acci-
« dental 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 1
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 cycluceros, 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.*
The walrus, though having so short a neck and so unwieldy a
hody, “can strike either upwards, or downwards, or sideways, with
“ equal dexterity.””* Iwas 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 toa
gr.at distance—it is said to even thirty feet; when they are
‘short and turned downwards he endeavours suddenly to pin the

7 Pallas, ‘Sp*cilegia Zoologica,’ °9 Lamont, ‘Seasuas with the Sos
tye. xiii, 1779, p. 18. Horses,’ 1861, p. 141.

34

Tarr IT,

514 The Descent of Man.

tiger to the ground and, in consequence, is dangerous to the
rider, who is liable to be jerked off the howdah.®

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 mary
infer from what follows that one form of weapon has cften
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 heing “ always: of
“ smaller size in the females than in the males.” The Camelidss
have, in addition to their true canines, a pair of canine-shaped
mcisors in their upper jaws.*' 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
radiments of these teeth. 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 pro-
genitor 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.

Yusks and horns are manifestly of high importance to their

% Sx a.sy Corse (‘Philosoph. American deer. See also Falconer

Transact. 1799, p. 212) on the
wanner in which the short-tusked
Mooknah variety attacks other ele-
ipuants.

31 Owen, ‘Anatomy of Verte-
brates,’ vol. tit, p. 349.

#2 See Ruppell (in ‘Proc. Zoolog.
Soc.’ Jan. 12, 1836, p. 3) on the
sanines in deer and antelopes, with
a pote by Mr. Martin on a female

(‘Palzont. Memoirs and Notes,’
vol. i, 1868, p. 576) on canines in
an adult female deer. In old malea
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 ridiment projects scarcelv half
an inch above the gums.

Cuar, XVI. Mammals—Greater Size of Male.

515

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 clephant, have been
known to weigh respectively 150, 160, and 180 pounds; and
even greater weights have been given by some authors. Wz.th
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.”** 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 the red-dcer 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.*° 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 (Callor-
hinus ursinus), a full-grown female weighing less than one-sixth
of a full-grown male.** Dr. Gill remarks that it is with the

33 Emerson Tennent, ‘Ceylon, 143. See also Owen, ‘ British

1859, vol. ii. p. 275; Owen, ‘ Bri-
tish Fossil Mammals,’ 1846, p. 245.

34 Richardson, ‘ Fauna Bor. Ame-
vicana,’ on the moose, Alces palmata,
pp. 236, 237; on the expanse of the
porns, ‘Land and Water,’ 1869, p.

F ssi. Mammals,’ on the Irish elk,
pp. 447, 455.

35 « Forest Creatures,’ by C. Boner
1861, p. 60.

36 See the very interesting paper
by Mr. J. A. Allen in ‘ Bw. Mua

516 The Descent of Man. Parr Li.

polygamous scals, the males of which are well known to fight
savagely together, that the sexes differ mach in size; the mono-
gamous species differing but little. Whales also afford evidence
of the relation existing between the pugnacity of the males aud
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,*’ 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 selec-
tion, 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 deerhound, the sexes of which differ more in
size than those of any other breed (though bloodhounds 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 383 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. Mr. Cupples

Comp. Zoolog. of Cambridge, United
States,’ vol. ii, No. 1, p. 82. The
weights were ascertained by a care-
ful observer, Capt. Bryant. Dr.
Gill in ‘Tne Amerjzan Nararalist,’
Jan. 1871, Prof. Shaler on the
relative size of the sexes of whales,
American Naturalist,’ Jun. 1873.

87 + Animal Economy,’ p. 45.

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,
1 Scrope’s ‘ Art of Deer Stalkirg

Unap. XVII. Mammals—Greater Size of Male. 517

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’ expe-
rience, 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
jn size between the male and female Scotch deerhound 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 thoir
characters to their male offspring alone; and thus-the great
inequality in size between the sexes of the Seotch deer-hound
may probabiy be accounted for.

hope tha Mr. Cupples will keep account and history of this famous
to his intention of publishing a fall breed.

518 The Descent of Man. Part II

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 de-
fending themselves; and the Oryx antelope, as I am intormed
hy 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 spe-
cially modified for defence.
With boars in the prime
of life (sce fig. 65) the
tusks in the Jower jaw are
used for fighting, but they
become in old age, as
Brehm states, so much
curved inwards and up-
wards over the snout,
that they can no longer
be used in this way
Fig. 65. Head ot Common wild boar, in prime They may, however, still

of life rum Brel). 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.

In the full-grown male Baburisa pig of Celehes (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 te a branch!
Their convex surfaces, however, if the head were held a little

39 Brehm, ‘Thierlehen,’ B. ii. ». 729-732.

Cuar. XVI. Mammals—Means of Defence. 519

laterally, would serve as an excellent guard ; and hence, perhaps,
itis that in old animals they “are generally broken off, as if lry
“ fighting.”*© 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. 66. skull of the Bubirusa Pig (from Wallace’s ‘ Malay Aichipelago’).

In the wart-hog (Placochoerus cethiopicus, 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

40 See Mr. Wallace’s interesting account of this animal, ‘The Malay
Archipelago.’ 1859, vol i. p. 435.

520 The Descent of Man. Part II.

tusks appear to have been specially modified to act as guards,
though no doubt they are to a certain extent used for this pur-
pose. 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.

Fig. 67. Head of female Aéthioptan wart-hog, from ‘Proc. Zool. Soc.’ 1869, shewing
tbe same characters as the male, though on a reduced scale.

N.B. When the engraving was first made, 1 was under the impression that it repre-
sented the male.

Lastly, the African river-hog (Potomochoerus penicillatus) has a
hard cartilaginous knob on each side of the face beneath the
eycs, 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 purpose of the
above-described projections and excrescences, that these were
covered with blood, and were scored and abraded in an extra-
ordinary manner.

Althouch the males of so many members of the pig family are

Cuar. XVIL Mammals—Means of Defence. 52)

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‘!
several miocene species, in none of which do the tusks appear
to have been largely developed in the males ; and Prof. Riitimeyer
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.” * The broad
ruff round the throat and chin of the Canadian lynx (elis
cunadensis) 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 ot
certain kinds (Otaria jubuta)** 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 Zoo-
‘ogical Gardens, witnout 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
aud 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

41 ¢ Atti della Soc. Italiana di Sc. 43 Dr. Murie, on Otaria, ‘ Proc.
Nat.’ 1873, vol. xv. fasc. iv. Zoolog. Soc.’ 1869, p. 109. Mr. J.

42 <The Times,’ Nov. 10th, 1857. A. Allen, in the paper above quoted
In regard to the Canada lynx, see (p. 75), doubts whether the hair,
Audubon and Bachman, ‘Quad- which is longer on the neck in the

cupeds of N. America, 1846, p. male than in the female, deserves ta
39. be called a mane.

522 The Descent of Man. Paxr IL.

‘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 eases,
os 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 de-
scribing 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
docs the male, when not a polygamist, select any particular
female? The general impression amongst breeders seems to be
that the inale accepts any female; and this owing to his eager-
ness, 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
hody of direct and indirect evidence wa» alvanced, 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
Scotlund with female red-deer, as I am informed by Sir Philip
Egerton and others.“

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
nourtship of one of the earcd seals (Callorhinus ursinus) are

‘* Mr. Boner, in his excellent “sanctuary of his harem, and car
desuription of the habits of the red- “ ries off trophy after trophy.” Ex-
deer in Germany (‘ Forest Creatures,’ actly the same thing occurs with
isl, p. 81) says, “while the stag seals, see Mr, J. A. Allen, ibid p
* sdetending his rights against one = 100.

‘ ntruder, another invades the

Cuav, XVII Mammals —Choice in Pairing. 523

given ® on the authority of Capt. Bryant, who had a:nple
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 agein.... 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 manncr
“ 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 stcal
“ 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
“ eats 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
“ tamily, scolding those who crowd or disturb the others, and
“fiercely driving off all intruders. This surveillance always
“ keeps him actively occupied.”

As 80 little is known about the courtship of animals in a state
of nature, I have endeavoured to discover how far our domesti-
cated quadrupeds evince any choice in their unions. Dogs
offer the best opportunity for observation, as they are carefully
attended to and well understesd. Many breeders have expressed
a strong opinion on this head. Thus, Mr. Mayhew remarks,
“The females are able to bestow their affections; and tender
“ yecollections 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
*gompanion of vulgar appearance, there often spriogs up
“ between the pair a devotion which no time can afterwards
“ agubdue. The passion; for such it really is, becomes of a more
than romantic endurance.” Mr. Mayhew, who attended
ghiefly to the smaller breeds, is convinced that the females are

4 Mr. J. A. Allen in ‘Bull. Mus. Comp. Zoolog. of Cambridge, United
States,’ vol. ii. No. 1, p. 99.

524 The Descent of Man. Part TL

strongly attracted by males of a large size.** The well-known
veterinary Blaine states“ that his own female pug 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 similiar 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 pro-
duced 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 prefer-
ence 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

*¢ ‘Dogs: their Management,” by ‘7 Quoted by Alex. Walker ‘Og
E. Mayhew, M.R.C.V.S., 2ud edit. Intermarriage,’ 1838, p. 276; ~e
1864, pp. 187-192. also p, 244,

Cuar. XVI. = Mammals—Choice in Pairing. §25

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 “* quotes various statements from French autho-
rities, and remarks, “ On voit des étalons qui s’éprennent d’une
“jument, et négligent toutes les autres.” He gives, on the
authority of Baélen, 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, “ Foemine majores et fortiores mares pre ceteris admittunt,
“ad eos confugiunt, a junioribus agitate, qui hos in fugam
* conjiciunt.”* 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 pre-
ferences are frequently exhibited, and much more commonly by
the female than by the male. This being the case, it is impro-
bable 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 temale
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.

QuapRuPeEDs 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

+ ¢Traite de l’Hérdd. Nat.’ tom. 49 ¢Ameenitates Acad.’ vol. iv
Bi, 1850, p. 296. 1788, p. 160.

526 Ihe Descent of Man. Parv I.

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, are said to be completely
mute excepting at this season. As the throats (de. the larynx
axd thyroid bodies?) 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
secms that young stags under three years old do not roar
or bellow; and that the old ones begin bellowing at the com-
niencement of the breeding-season, at first only occasionally and
inoderately, 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 pre-
paring to fight; but this may mercly 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 advan-
tage 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, as is well known to the hunters who in wild countries

' Oven, ‘ Anatomy of “erte 3 See, for instance, Major W.
brates,’ vol iii, p. 585. Ross King (¢ The Sportsman iv

3 [bid p 595, Canada’ 1866, p. 53, 131) on the

Gnap. XVHI. Mammatls.—Vocal Organs. 527

imitate her cry. If we could believe that the male had the
power to excite or allure the female by his voice, the perivdical
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 ot
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 in-
herited effect on the vocal organs of the stag, as well as of other
male animals? This appears to me, in our present state ot
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.‘
The gibbons rank among the noisiest of monkeys, and the
Sumatra species ( ylobates syndaciylus) is also furnished with an
air sack; but Mr. Blyth, who has had opportunities for observa-
tion, does not believe that the male is noisier than the female.
Hence, these latter monkeys prcbably use their voices as a
mutual call; and this is certainly the case with some quadrupeds,
for instance the beaver.’ Another gibbon, the H. agilis, is re-
markable, from having the power of giving a complete and
correct octave of musical notes,® which we may reasonably sus-
pect 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 con-
cert, and often continue it during many hours, the females,
sometimes joining in with their less powerful voices. An
excellent observer, Rengger,’ 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

tatits of the moose and wild rein- 6 C. L. Martin, ‘General Intro

deer. duction to the Nat. Hist. of Mamm
+ Owen, ‘ Anatomy of Verte- Animals,’ 1841, p. 431.

brates.’ vol. iii. p. 600. 7 ‘Naturgeschichte der Saage

5 My. Green, in ‘Journal of Lina, thiere von Paraguay,’ 1830, ». 15
Se’ vol. x. Zoology, 1869, p. 362. QL.

528 The Descent of Man. Part 11,

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 ugilis, 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 gailinaceous birds whilst
courting the females. In another allied kind of seal, the bladder-
nose (Cystophora cristatu), 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; it 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.®

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

1824, p. 94. Pennant has also

collected information from the
sealers on this animal. The fullest

* Qi: 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.

account is given by Mr. Brown, ia
‘Proc. Zoolog. Soc.’ 1868, p 435,

Yuap, XVI. Afammals— Odvurs entiited. 520

many other quadrupeds the glands are of the same size in botk
sexes? 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 seéreticn
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. Or
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. Besides
the general odour, permeating the whole body of certain rumi-
nants (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 J have myself seen in an
antelope. They are “usually larger in the male than in the
“femsle, and their development is checked by castration.”"-
According to Desmarest they are altogether absent in the female
of Antilope subgutturusa. 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

9 As with the castoreum of the
beaver, see Mr. L. H. Morgan’s
Most interesting work, ‘The Ame-
rican Beaver,’ 1868, p. 300. Pallas
( Spic. Zoolog.’ fase. viii. 1779, p.
23) has well discussed the odorifer-
ous glands of mammals. Owen
(‘ Anat. of Vertebrates,’ vol. iii. p.
334) also gives an account of these
glands, including those of the ele-
puant, and (p. 763) those of shrew-
mice. On Bats, Mr. Debson in

Proc. Zoolog. Soc.’ 1873, p. 241.

85

10 Rengger, ‘ Naturgeschichte der
Siugethiere von Paraguay,’ 1830,
s. 855. This observer also gives
some curious particulars in regard
to the odour.

11 Owen, ‘Anatomy of Verte-
brates,’ vol. iii. p. 632. See, also
Dr. Murie’s observations on these
glands in the ‘Proc. Zoolog. Soc.’
1870, p. 340. Desmarest, On the
Antilope subyutturosa, ‘Mamma.
logie,’ 1820, p. 455,

530 The Descent of Man. Part U

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 con-
sistence, 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.”

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
s,emales 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 Jarge and complex glands, furnished
with muscles for everting the sack, and for closing or opening
the orifice, have in some cases been developed. The develop-
ment 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.

Dev:lopment 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 V'ragelap hus
scriptus’ (see fig. 70, p. 544) and Purtua pictu, may be given as

'2 Pallas, ‘Spi-ilegia Zoolog.’ fase. '* Dr, Gray, ‘Gleanings from the
xiii, 1799, p. 24; Lesmsulins, ‘Dict. Menagerie at Knowsley,’ pl. 28.
Class. d@’Hist. Nat.’ tom. ii’. p. 586,

Unar, XVII. Aammals—Development of Hair. 531

instances. When stags, and the males of the wild goat, are
enraged or tervified, these crests stand erect;* 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 an-
telopes, 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 dAmmotragus 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.

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. ‘hus the bull alone has curled hair on the
forehead.'® In three closely-allied sub-genera of the goat family,
only the males possess beards, sometimes of large size; in twu
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 it is so small at other times
that it may be called rudimentary. 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 Myctes caraya and
Pithcia satanus (fig. 68). So it is with the whiskers of some
species of Macacus," 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 (Bovids), 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 dewlap of the bull, or the crests ot
hair along the backs of certain male antelopes, are of any use
to them in their ordinary habits. It is possible that the im-
mense 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

% Judge Caton on the Wapiti, p. 236

fransact. Ottawa Acad. Nat. 18 See Dr. Gray’s ‘Cat. of Mam.
Sciences,’ 1868, pp. 36, 40; Blyth, malia in British Museum,’ part iii,
‘fand and Water,’ on Capra xgu- 1852, p. 144.
grus, 1867, p. 37. 7 Rengger, ‘Siiugethiere,’ &e. «

16 ¢Hunter’s Essays and Observa- 14; Desmarest, ‘Mammalogie,’ p
tions,’ edited by Owen, 1861, vol. i. 66.

532 The Descent of Man. Part IL.

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 quad-
rupeds, certain characters, apparently not derived through re-
version from any wild parent-form, are contined to tle males,

Fig, 68. Pithecia satanas, male (from Brehm).

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." The
mane, which occurs only in the rams of an African breed of

“8 See the chapters on these ‘Variation of Animals under Domes-
several animals in vol, i. of my tication;’ also vol. ii. p. 733 also

Cuar. XVII Alammals—Ornamental Colours. 533

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
ixeprobable; 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, &c., 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 mammais is doubtful.

Colour of the Hair and of the Naked Skin.—I will first give
oriefly 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.” In the Didelplis opossum of Cayenne

chap. xx. on the practice of selection ogue,’ ibid. p. 157.
by semi-civilised people. For the ” Osphranter rufu , Gould, ‘ Mam-
Berbura goat, see Dr. Gray, ‘Cata- mals of Australia,’ 1863, vol on

534 The Descent of Man. Vand I

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 soine seasons of the year than at others,
“and the fur of the male is generally brighter than that ot
“the female.”” 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.”
Mr. Dobson also remarks, with respect to these animals: “ Dif-
“ ferences, 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 orna-
mental. 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 rerely exhibit sexual
differences of any kind, including colour. The ocelot (/elis
pardalis), however, is exceptional, for the colours of the female,
compared with those of the male, are “moins apparentes, le
“fauve étant plus terne, le blanc moins pur, les raies ayant
“moins de largeur et les taches moins de diamétre.”# The
sexes ot the allied Melis 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 Ofuria nigrescens of the
southern hemisphere is of a rich brown shade above; whilst the

Oc the Didelpkis, Desmarest, United States,’ 1869, p. 207. Mr.
*Masamalogie,’ p. 256. Dobson on sexual characte:s in the
@ “Annals and Mag. of Nat. Hist.’ Chiroptera, ‘Proc. Zoolog. Soc ‘
Nov. 1867, p. 325. On the Mus 1873, p. 241. Dr. Gray on Sloths,
minutus, Desmarest, ‘Mammalogie, ibid. 1871, p 436.
. 504, 22 Desmarest, ‘Mammalogie,’ 1820.
2 J. A. Allen, in ‘Bulletin of p. 220. On Felis nutis, Rengyer
Mus. Comp. Zoolog. of Cambridge, ibid. ». 194

Cuar. XVIMN. Mammals—Ornamental Colours.

535

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 groenlundici
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,
sud can “hardly be distinguished among the icy hummocks and
“ snow, their colour thus acting as a protection.”

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
(Portsx 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
horniess female. JT 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
emaxculated 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™ 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-orna-
mented species of Tragelaphus the males are darker than the
hornless females, and their crests of hair are more fully dercloped.
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 fenale. In
the Cape eland also, the male is slightly darker than the female.”

in the Indian black-buck (A. bezoartica), which belongs to
another tribe of antelopes, the male is very dark, almust black ;
whilst the hornless female is fawn-coloured. We meet in this

23 Dy. Murie on the Otaria, ‘ Proc.
oul. Soc? 1869, p. 108, Mr. R.

142; also Dr. Gray, ‘ Gleaning:
from the Menagerie of Knowsley.

hrowu, on the P. groenlandica, ibid.
1868, p. 417. See also on the
.elours of seals, Desmarest, ibid. p.
243, 249.

24 Judge Caton, in ‘Trans. Ottawa
Acad of Nat. Sciences,’ 1868, p. 4.

25 Dr, Gray, ‘Cat. of Mamm. in
Brit. Mu.’ part iii. 1852, pp. 134-

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 8. Africa,’ pl. 41
and 42. There are also many of
these antelopes in the Zoological
Gardens.

536 The Descent of Mai.

Paar Ih

species, as Mr. Blyth informs me, with an exactly similar series
of facts, as in the Porta 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 niyer
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 (4. goryo:) “the colours of the
“male are nearly the same as those uf the female, only deeper
“and of a brighter hue.” > 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 aud the female Capra egagrus are said to be
more uniformly tinted than their males. Deer rarely present
any sexual differences in colour. Judge Caton, however,
infurms me that in the males of the wapiti deer (Cervus
canadensis) the neck, belly, and legs are much darker than iu
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 ex-
clusively confined to the blue winter or breeding coat; so that
this case may be compared with those given in a previons
chapter of closely-altied or representative species of birds, which
differ from each other only in their breeding plumage” The
tewales of Cervus pwudosus 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.* Lastly, as I am informed by Mr. Blyth, the

26 On the Ant. niger, see ‘Proc.

Zool. Soc.’ 1850, p. 133. With re-
spect to an allied species, in which
there is an equal sevual difference
in colour, see Sir S. Baker, ‘The
Aibert Nyanza,’ 1866, vol. ii. p.
827. For the A. sing-sing, Gray,
‘Cat. Bo Mus.’ p. 100, Desmarest,
‘Mammalogie,’ p. 468, on the A.
rauwae = Audrew Smith, + Zovlogy
4fS. Africa,’ on the Gun.

27 “Ottawa Academy of Sciences,
May, 21, 1868, pp. 3, 5.

*8'S. Miller, on the Banteng,
‘Zoog. Indixchen Archipel.’ 1839.
1844, tab. 353 see also Raffles, as
quoted by Mr. Blyth, in ‘ Land and
Water,’ 1867, p. 475. On goats,
Dr. Gray, ‘Cat. Brit, Mus.’ po 146;
Desmarest, ¢Mammalogie,’ p. 482.
On the Cervus paledosus, Re igger.
ide Sig or

Unap. XVILL = Wammals—Ornamental Colours.

ES?

mature male of the beautifully coloured and spotted axis deer is
vonsiderably darker than the female; and this hue the castrated
male never acquires. ‘

The last Order which we need consider is that of the Primatcs
The male of the Lemur macacu is generally coal-black, whilst the
female is brown.” Of the Quadrumana of the New World. the
females and young of Mycetes curaya are greyish-yellow and like
each other; in the second year the young male becomes reddish-
Urown; in the third, black, excepting the stomach, which, how-
ever, becomes quite black in the fourth or fifth year. There is
also a strongly-marked difference in colour between the sexes of
Mycct-s seniculus and Cebus capucinus ; the young of the former,
and I believe of the latter species, resembling the females.
With Pithecia kucocephala 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 Aéeles maryinatus ig tinted yellow in the male and
white in the female. Turning to the Old World, the males of
Hylotates 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. In
the beautiful Cercopithecus diuna, 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
woustache monkey (Cercopithecus cephus) the only difference
between the sexes is that the tail of the male is chesnut and that
of the female grey; but Mr. Bartlett informs me that all the
hues becomes more pronounced in the male when adult, whilst
in the female they remain as they were during youth. Ac-
cording to the coloured figures given by Solomon Miiller, the
male of Semuopithecus chrysumelus is nearly black, the female
being pale brown. In the Cercopithecus cynosurus and g7tsev-
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,

Lastly, in the baboon family, the adult male of Cynocephulus
homadryus differs from the female not only by his immense

23 Solater, ‘ Proc. Zool. Soc.’ 1866,
p 1. The same fact has also been
fully ascertained by MM. Pollen and
van Dam, See. also, Dr. Gray in
‘Annals and Mag. of Nat. Hist.’ May
1871, p. 340.

4° On Mycetes, Rengger, ibid. »,

14; and Brehm, ‘Illustrirtes Thier-
leben,’ B. i. s, 96, 107. On Ateles,
Desmarest, ‘Mammalogie,’ p. 75.
On Hylobates, Blyth, ‘Land and
Water,’ 1867, p. 135. On the Sem
nopithecus, S. Miuiller, ‘Zooy. In
dischen Archipel.’ tab, x.

538 The Descent of Alan. Parr II,

mane, but slightly in the colour of the hair and of the naked
callosities. In the drill (CU. eucopiceus) 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 (U
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

Fig. 69. Head of male Mandrill (from Gervais, ‘ Hist. Nat. des Mammiferes’).

1s 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 sup4rieures de lenrs
“culisses et le grand espace nu de leurs fesses sont également
“ eolorés du rouge. le plus vif, avec un mélange de bleu qui ne

Cnae, XVILL Mammals—-Ornamental Colours. 539

“manque réellement pas d’élégance.”** When the animal is
excited all the naked parts become much more vividly tinted.
Several authors have used the strongest expressions in de-
scribing these resplendent colours, which they compare with
those of the most brilliant birds. Another remarkable pecu-
liarity 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 protuber-
ances 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
prighter 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
(Mueacus 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 occa-
sionally, or during certain seasons, exhibit some traces of the red.
Although he is thus less ornamented than the female, yet in the
jarger 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 eases 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 thereforo
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. Analo-

. gous cases occur in nature: Mr. Bartlett has seen many black
varieties of the jaguar, leopard, vulpine phalanger, and wombat;

3} Gervais, ‘ Hist. Nat. des Mam- Desmarest, ‘ Mammalogie,’ p. 70.
m.iféres,’ 1854, p. 103. Figures are Geoltroy St.-Hilaire and F. Cuvier,
given of the skull of the male. Also ‘Hist. Nat. des Mamm.’ 1824, ton. i

540 The Descent of Man. Part lL,

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 sume 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 tha
diversified, vivid, and contrasted colours of certain quadrupeds,
for instance, of the above monkeys and antelopes can thus bo
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 thcir 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 munmals, which present other and strongly-marked
secondary scxual characters; these being likewise due to sexual
selection. -

Quadrupeds manifestly take notice of colonr. Sir S. Baker
repeatedly observed that the African elephant and rhinoccros
attacked white or grey horses with special fury. J have else-
where shewn™ 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 zetra, 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
* yequire this, the female being an animal somewhat similar to
“ himself, was sufficient to rouse him,” *

In an earlicr 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

32 ¢ The Variatien of Animals and 33 ¢ Kssays und Observations hy

Plants under Domestication,’ 1858, J. Hunter,’ edited by Owen, 1861,
vol. ii, pp. 102, 103. vol. i, p. 194,

Tuas, XVIIL Mammals— Ornaments. 541

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 ;’*—as negrocs 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 gandily-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
maie 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
temale. In both classes the male assumes the characters proper
to his sex shortly before the age of reproduction; and if emas-
culated 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
ne, 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 indi-
viduals 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,

3 Sir S, Baker, ‘The Nile Tributaries of Abyssinia,’ 1867.

542 The Descent of Man. Part IL

Equal transmission of ornamental characters to both sexes.— With
many birds, ornaments, which analogy leads us to believe were
primarily acquired py 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 pro-
tection; 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,®° 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 appa-
rently is the direct result of the conditions to which they have
long been exposed. Pallas** states that in Siberia a change of
this nature occurs with the wolf, two species of Mustela, the
domestic horse, the Lquus henionus, the domestic cow, two
species of antelopes, the musk-deer, the roe, elk, and rein-
deer. 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 profit-
ing 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

38 Fiber zibethicus, Audubon and Glirium ordine” 1778, p.7. What
Bachman, ‘The Quadrupeds of N. Ihave calied the roe is the Capreolus
America,’ 1846, p. 109. sibiricus subecaudatus of Pallas.

™ *Nova species Quadrupedum e

Cuar, XVII Mammals—Spots and Stripes. 543

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.
Uence it is, as Mr. Belt believes,*” that the skunk is provided with
a great white bushy tail, which serves as a couspicuous warning.

Although we mustadmit 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 con-
spicuous and too singularly arranged to allow us to suppose that.
they serve fur 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 picia
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 Orcas
derbyanus than in the female ;—when we see a similar difference
between the sexes of the curiously-ornamented Tragelaphus
sertp.tus (fig. 70),—we cannot believe that differences of this kind
ave of any service to either sex in their daily habits of life. It
scelus # 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 kocdoo
(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. pyyarga 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
oklong white mask, narrowly-edged with black, covers the face

87 + Tne Naturalist in Nicaragua,’ p. 249.

544 The Descent of Man. Part If,

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 Damulis
allifrons the colouring of the head differs from that in the last
species in a single white stripe replacing the three stripes, and

hig. 70, ‘lragelapbus scriptus, male (from the Knowsley Menagerie).

in the ears being almost wholly white.** After having studied
to the best of my ability the sexual differences of animals be-
longing 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.

38 See the fine platesin A.Smith’s ‘Gleanings from the Menagerie of
‘Zoology of S. Africa,’ and Dr.Gray’s Knowsley.’

Cuar. XVII. Mammals— Spots and Stripes. 545

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* 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

Fig. 71. Damalis pygarga, male (from the Knowsley Menagerie).

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 on the open plains of South Africa. Burchell’? in de-
scribing a herd says, “their sleek rihs glistened in the sun, and
“ the brightness and regularity of their striped coats presented a
“ picture of extraordinary beauty, in which probably they are

29 ¢ Westminster Review,’ July 1, 40 «Travels in South Africa,’ 1824.
1867, p. 5. se vol. ii, p. 315,

546 The Descent of Man. Parr Il,

‘not surpassed by any other quadruped.” But as throughout
the whole group of the Equide the sexes are identical in colour,
we have here no evidence ot 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
saine view to the Royal Tiger and beautiful Zebra.

Wo 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 aro
spotted. I will specify some of the steps in this series. The
Mantchurian deer (Cervus mantchricus) 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 (Hylaphus porcinus) the spots are extremely con-
spicuous during the summer when the coat is reddish-brown,
but quite disappear during the winter when the cout is brown.”
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 in-
formed 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 anit
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

‘| Dr. Gray, ‘Gleanings from the deer of Ceylon, says it is more
Menagerie of Knowsley,’ p. 64. brightly spotted with white than
Mr. Blyth, in speaking (‘Land and the common hog-deer, at the season
Water? TRUS. p. Fz) ef the heg- when it renews its horns.

Onap. XVUL = Mantnals—Spots and Stripes. 547

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 to-
gether two groups, for it is intermediate in certain osteological
characters between the pachyderms and ruminants, which were
formerly thought to be quite distinct.

A curious difficulty here arises. If we admit that colourcd spots
and stripes were first acquired as ornaments, how comes it that
80 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
ot 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 Miller has suggested
tome 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 varics
and becomes reddish-brown, grey, or black, the stripes on the
shoulders and even on the spine frequently disappear, though wu
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.** Hence the dis-
appearance of the spots and stripes in our adult existing deer,

*2 Falconer and Cautley, ‘Proc. 43 ¢The Variation of Animals and

Gsslog. Soc.” 1843; and Falconer’s Plants under Domestication,’ 186%,
Pal. Memoirs,’ vol. i. p. 196. vol. i. p. 61-64,

548 The Descent of Man. Part IL

pigs, and tapirs, may be due to a change in the general coleur 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
‘lisappearance of stripes; the species of Asinus which inhabit
the Asiatic continent are destitute of stripes, not having even

Fig. 7. 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.

the cross shoulder-stripe, whilst those which inhabit Africa are
conspicuously striped, with the partial exception of A. tentopus,
which has only the cross shoulder-stripe and generally some
faint bars on the legs; and this species inhabits the almost inter-
mediate region of Upper Egypt and Abyssinia.**

44 «Proc. Zool. Soc.’ 1862, p. 164. Landw,’ Bd. sliii. s, 222.
See, also, Dr. Hartmann, ‘Ann. d

Cuar. XVIII. Beauty of the Quddrimmana., 549

Quadrumana.—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)

Fig. 75. Head of Ateles marginatus. Fig. 76. Head of Cebus vellerosus.

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;

550 The Descent of Man. Part IL

and it is incorceivable that they can be of use in any ordinary way
to these animals. Uf 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 addi-
tional evidence of the action of sexual selection in the greater
size and strength of the males, and in the greater development of
iheir canine teeth, in comparison with the females.

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 lastotus is dirty flesh-coloured, with a
defined red spot on each cheek. The appearance of Cercocebus
xthiops is grotesque, with its black face, white whiskers and
collar, chesnut 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,** being
often pure white, sometimes bright yellow, or reddish. The
whole face of the South American Brachyurus calvus is of a
“slowing scarlet hue;” but this colour does not appear until
the animal is nearly mature.** 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
aud Rhesus, in which the face and the posterior parts of the body
are brilliantly coloured in one sex alone. In these latter cascs
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.

48 I observed this fact in the ‘Hist. Nat. des Mammiféres.’ tom,
Zoological Gardens; and many cases i. 1824,
inay be seen in the colcured plates in 46 Bates, ‘The Naturalist on the
Jeoffroy St.-Hilaire and F. Cuvier, Amazons,’ 1863, vol. ii. p. 310.

rn

Cuar. XVIIL Beauty of the Quadrumana. a4

Although many kinds of monkeys are far from beautiful accord-
ing to our taste, other species are universally admired for their
elegant appearance and bright colours. The Semnopithecus
nemeus, though peculiarly coloured, is described as extremely

552 The Descent of Man. Van II

pretty; the orange-tinted face is surrounded by long whiskers
of glossy whiteness, with a line of chesnut-red over the eye-
brows; 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 chesnut surmcunts the chest; the thighs are
black, with the legs chesnut-red. I will mention only two other
monkeys for their beauty; and I have selected these as pre-
senting slight sexual differences in colour, which renders it
in sore 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 chesnut, 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
coiour 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 chesnut; 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
eye-brows and a long white peaked beard, of which the basal
portion is black.‘

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

_ Thave seen most of the above Mr. W. C. Martin’s ‘Nat. Hist. of
monkeys in the Zoological Society’s Mammalia,’ 1841, p. 460; see alsc
Gardens, The description of the pp. 475, 523

Semnoithecus nemeus is taken from

Caar, XVIII. Mammals—Summary. 553

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,

Fig. 78. Cercopithecus diana (from Brehm).

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 power-
ful odours emitted by the males during the breeding-season; the
odoriferous glands having heen acquired throngh sexual
sclection. Whether the same view can he extended to the voice

‘554 The Descent of Man. Parr Il,

is doubtful, for the vocal organs of the males must have been
strecgthened by use during maturity, under the powerful excite-
ments 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. Thore is even reason to suspect that the
branching horns of stags, and the elegant horns of certain ante-
lopes, though properly serving as weapons of offence er 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, socommon 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 enriouslv
arranged, without being of the least apparent use asa vrotection,
and especially when they are associated with various other orna-
mental appendages, we are led by analogy to the same conelusion
namely, that they have been acquired through sexual selection
although transmitted to both sexes. That conspicuous anc
diversified colours, whether confined to the males or common tc
both sexes, are as a general rule associated in the same groups
and sub-groups with other secondary sexual churacters 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
ns far as colour and other ornaments are concerned, has prevailed
far more extensively with mammals than with birds; but
wc apons, such as horns and tusks, have often been transmitted
either exclusively or much more perfectly to the males than to the
females. ‘his is surprising, for, as the males generally use their
weapons for defence against enemies of all kinds, their weapons
would have becn of service to the females As far as we can seo,
their absence in this sex can be accounted for only by the

Cuap, XVILL. Mamimais—Suumary. 555

form of inheritance which has prevailed. Finally, with quad-
rupeds 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
oth,

{ 556 )

Parr III.
SEXUAL SELECTION IN RELATION TO MAN,

AND CONCLUSION.
Jee

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.

Wire mankind tho differences between the sexes ave greater

than in most of the Quadrumana, but not so great as in some,

for instance, the mandritl. 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,' 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 some-

“thing of the colour of half-roasted coffee”? 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.

! Schaaffhausen. (ranslation in 2 ¢Phe Heart of Africa,’ Englisl

* Aathropologizal Review,’ Gct. 1868, Transl. 1875, vol. i p. 544.

pp. 409, 420, 427.

Man— Sexual Differences.

Cuap, XIX. 557

Man is more courageous, pugnacious and energetic than
woman, and has a more inventive genius. His brain is abso-
lutely 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;* 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 scx 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 abun-
dant 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 ditfer widely; they likewise resemble the
mature female much more closely than the mature male. The
female, however, ultimately assumes certain distinctive cha-
racters, and in the formation of her skull, is said to be inter-
mediate between the child andthe man.‘ Again, as the young of
closely allied though distinct species do not differ nearly samuch
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 sku? 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 chesnut-
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.*

3 Ecker, translation in ‘ Anthro-
pological Review,’ Oct. 1868, pp. 351-
356. The comparison of the form
of the skull in men and women has
veen followed out with much care
oy Welcker,

4 Ecker and Welcker, ibid. p. 352,

355; Vogt, ‘Lectures on Man,’ Eng,
translat, p. 81.
5 Schaaff hausen,
Review,’ ibid. p. 429.
® Pruner-Bey, on negro infants
as quoted by Vogt, ‘Lectures un
Man,’ Eng. translat. 1864, p. 189:

‘ Anthropolog.

The Descent of Man. Pant IIL,

358

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
the Cebus azare.? The males of most species are larger ani
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 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.® 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 isa 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 in S:ikhim, the Bhoteas, Hindoos, Burmese, and

for further facts on negro infants, 7 Rengger, ‘Siiugethiere,’ &c.

as quoted from Winterbottom and
Camper, see Lawrence, ‘ Lectures on
Physiology,’ &c. 1822, p. 451. For
the infants of the Guaranys, see
Rengger, ‘Sdugethiere, &c. s. 3.
See also Godron, ‘ De }’Espéce,’ tum.
ii, 1859, p. 253. For the Austra-
lians, Waitz, ‘Introduct. to Anthro-
pology,’ Erg. translat. 1863, p. 99.

1830, s. 49.

8 As in Macacus cynomolgus (Dese
marest, ‘Mammalogie,’ p. 65), and
in Hylobates agilis (Geoffroy St.-
Hilaire and F. Cuvier, ‘Hist. Nat.
des Mamm,’ 1824, tom. i. p. 2).

® ¢ Anthropological Review,’ Out
1868, p. 353

Cuap, XIX. Man—Sexcual Differences.
S

559

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 huc,
being often pure white, sometimes yellow or reddish.”

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." 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 con-
siderably 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 through-
out the animal kingdom. Inthe excellent observations made on
board the Novara,” 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 thatin 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

‘0 Mr. Blyth intorms me that he thus Mr. D. Forbes has never, as he

has only seen one instance of the
beard, whiskers, &c., in a monkey
becoming white with old age, as
is so commonly the case with us.
This, however, oecurred in an
aged Macacus cynomolgus, kept
in confinement, whose moustaches
were “remarkably long and hu-
“ man-like.” Altogether this old
morkey presented a ludicrous re-
sezablanoe to one of the reigning
monarchs of Europe, after whom he
was universally nicx-named. In
certain races of man the hair on
the heed hardly ever becomes grey ;

informs me, seen an instance with
the Aymaras and Quichuas of S.
America.

1 This is the case with the fe-
males of several species of Hylobates,
see Geoffroy St.-Hiliare and F, Cu-
vier, ‘Hist. Nat. des Mamm.’ tom. i.
See, also, on H. lar. ‘Penny Cr-
clopedia,’ vol. ii. pp. 149, 150.

2 The results were deduced by
Dr. Weisbach from the measure-
ments made by Drs, K, Scherzer
and Schwarz, see ‘ Reise der Novara:
Anthropolog. Theil,’ 1867, ss, 216,
931, 234, 258, 239, 269.

560 The Descent of Man. Pasr IL

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 seo
this amongst ourselves. In the Island of St. Kilda, according to
Martin," the men do not acquire beards until the age of thirty
or upwards, and even then the beards are very thin. On
the Europxo-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. East-
ward of India beards disappear, as with the Siamese, Malays,
Kalmucks, Chinese, and Japanese; nevertheless the Ainos,° 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.'® On the
other hand, the Papuans of the Malay Archipelago, who are
nearly as black as negroes, possess well-developed beards.”
In the Pacific Ocean the inhabitants of the Fiji Archipelago have
large bushy beards, whilst those of the not distant archi-
pelagces 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, namcly
Nunemaya, “the men have splendid beards;’ whilst on the
other islands “they have, as a rule, a dozen straggling hairs for
“a beard.” ®

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;

13 ‘Voyage to St. Kilda’ (3rd
edit, 1753), p. 37.

4 Sir J. E. Tennent, ‘Ceylon,’
vol. ii. 1859, p. 107.

15 Quatrefages, ‘ Revue des Cours
Scientifiques,’ Aug. 29, 1868, p.
630; Vogt ‘Lectures on Man,’
Eng. translat. p. 127.

16 On the beards of negroes, Vost,
‘Lectures,’ &c. p. 127; Waitz, ‘ In-
troduct, to Anthropology,’ Engl.
translit, 1865, vol. i. p. 96. It is

remarkable that in the United States
(‘Investigations in Military and
Anthropological Statistics of Ame-
rican Soldiers,’ 1869, p. 569) the
pure negroes and their crossed off
spring seem to have bodies almost
as hairy as Europeans.

'7 Wallace, ‘The Malay Arch.’
vol. ii. 1869, p. 178.

18 Dr. J. Barnard Davis On Oce-
anic Races, in ‘ Anthropolog. Review,’
April, 1879, pp. 185, 191.

Cuap, XIX. Man—Law of Battle. 561

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.® I am informed by Mr. D.
Forbes, who particularly attended to this point, that the Aymaras
aud Quichuas of the Cordillera are remarkably hairless, yet in
old age a few straggling hairs occasionally appear on the chin.
The 106en 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.” 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,”

In the previous chapters we have seen that with mammals,
birds, fishes, insects, &c., 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 cha-
racters 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. Sono doubt it was
in ancient times; “nam fuit ante Helenam mulier teterrima belli
causa.” With some of the North American Indians, the con-
test is reduced to a system. That excellent observer, Hearne,”

19 Catlin, ‘North American In-
dians,’ 3rd edit. 1842, vol. ii. p. 227.
On the Guaranys, see Azara, ‘ Voy-
ages dans |’Amerique Mérid.’ tom.
fi. 1809, p. 58; also Rengger,
* Shugethiere von Paraguay,’ s. 3.

*0 Prof. and Mrs, Agassiz (‘ Jour-
ney in Brazil,’ p. 530) remark that
the sexes of the American Indians
uiffer less than those of the negroes
snd of the higher races. See also
Rengger, ibid. p. 3, on the Guaranys.

37

21 Ruitimeyer, ‘Die Grenzen der
Thierwelt; eine Betrachtung za
Darwin’s Lehre,’ 1868, s. 54,

22¢A Journey from Prince of
Wales Fort.’ 8vo. edit. 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 S
America see Azara, ‘ Voyages,’ &e
tom. ii. p. 94,

502 Lhe Descent of Man. Part [11

says :—“ It has ever been the custom amcng these people foz
“the men to wrestle for any woman to whom they are at-
“ tached; and, of course, the strongest party always carries off
“ the prize. A weak man, unless be 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 through-
out 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,” that the Jaw 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 otlfers, 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 oblite-
rated. ‘lhe case is almost parallel with that of many male
Ruminants, in which the canine tecth 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.

*3 On the fighting of the male p. 423. On Presbytis entellus, see
gorillas, see Dr, Savage, in ‘Boston th: ‘Indian Field,’ 1859, p. 146.
sournal of Nat. Hist.’ vol. v. 1847,

Ouap. XIX. Mental powers of Man and Woman. 563

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 in-
heritance 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. Iam 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-hoar 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; there-
fore it is hxely 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

564 The Descent of Man. Pant IL

of the lower races, and therefore of a past and lower state of
civilisation.

The chief distinction in the intellectual powers of the twe
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
swvages, there have been struggles between the males during
raany 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 night expect that they
would at least tend to be transmitted chiefly to the male ofispring
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 per-
fection, save that one has higher energy, perseverance, and
eourage, the latter will generally become more eminent in every
pursait, and will gain the ascendancy.* He may be said
w possess genius—for genius has been declared by a great

74 J. Stuart Mill remarks (The “require most plodding, and long
Subjection of Women,’ 1869, p.122), “hammering at single thoughts.”
“The things in which man mest What is this but energy and per
* excels woman are those which severance?

Cuar. XIX. Mental powers of Man and Woman. 565

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 imagi-
nation 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 ta
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,”
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 goud, 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 genera-
tions 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 theix

* Maudsley, ‘Mind and Body,’ p. 31.

356 The Descent of Man. Part ILL

mental powers, and, as a consequence, the present inequality
botween the sexes,”

Voice and Alusical 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 uppears 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 pro-
“minent growth of the thyroid, &c., which accompanies the
“ elongation of the cords.”* With respect to the cause uf 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 ex-
citement of love, rage and jealousy. According to Sir Duncan
Gibb,* the voice and the form of the larynx differ in the different
races of mankind; but with the Tartars, Chinese, &c., the voice
of the male is caid 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. Ivsects 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 pro-
duced consist, I believe in all cases, of the same note, repeated
rhythmically ;* 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 tle

76 An observation by Vogt bears “skulls.” But Vogt admits (‘Lec-

on this subject: he says, “It is a
“ remarkable circumstance, that the
“difference between the sexes, as
“regards the cranial cavity, in-
“ereases with the development of
‘the race, so that the male Euro-
pean excels much more the femile,
“than the negro the negress.
“Welcker confirms this statement
*of Huschke frcm his measure-
‘ments of uegro and German

tures on Man,’ Eng. translat. 1864,
p- 81) that more observations are
requisite on this point.

* Owen, ‘Anatomy of Verte-
brates,’ vol. iii, p. 603.

78 ¢ Journal of the Anthropolog
Soe.’ April, 1869, p. lvii. and ixvi.

28 Dr. Scudder, ‘Notes on Stri-
dulation,’ in ‘ Proc. Boston Soc of
Nat. Hist.’ vol. xi, April, 1863.

Har. XIX, Man —Musical Powers. 567

air-breathing Vertebrata necessarily possess an apparatus for
inhaling and expelling air, with a pipe capable of being closed
atone end. Hence when the primeval members of this clase
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 moditied 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. Ev3ry one kiows how much
birds use their vocal organs as a mears of couriship; and some
species likewise perform what may be called ins‘rumental music.

In the class of Mammals, with which we are here more par-
ticularly concerned, the males of almost all the species use their
voices during the breeding-season much more than at any other
time; aud some are absolutely mute exceptin: at this season.
With other species both sexes, or only the females, use their
voices as a love-call. Considering there 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 consilering that in most of the
lower classes the sounds produced by the male3, serve not only
to call but to excite or allure the female, it is 1 surprising fact
that we have not as yet any good evidence that these organs are
used by male mammals to charm the jemaler. The American
Mycetes caraya perhaps forms an exception, as does the Hylubates
agilis, an ape allied to man. This gibbon has an extremely loud
but musical voice. Mr. Waterhouse stutes.° “It appeared to
* me that in ascending and descending tie 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 compo-
“ sition, excepting as 1egards its loudness,” Mr, Waterhouse
then gives the notes. Professor Owen, who is a musician, con-
firms the foregoing statement, and remarks, though erroneously,
that this gibbon “alone of brute mammals may be said to
“ging,” It appears to be much excited after its performance.

% Given in W. C. L Martin’s Owen, ‘Anatomy of Vertebrates,
‘General Introduct. to Nat. Hist. of — vol. iii. p, U0,
Mamm. Animals,’ 1841, p. 432;

563 The Descent of Man. Parr Lil.

Onfortunately, 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 Zoo-
logical 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, how-
ever, at last a clear account by a well-known observer, the Rev.
8. Lockwood," 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 confine-
ment, 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 aérial “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 con-
tinuity 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 sen-
sitive 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.” As stated

31 The ‘American Naturalist,’ 32 Helmholtz, ‘Theorie Phys, de
1871, p. 761. la Musique,’ 1808, p. 187.

Cnap. XIX, Man— Musical Powers.

569

in a previous chapter, similiar observations have been maie
on the hairs of the antenns of gnats. It has been positively
asserted by good observers that spiders are attracted by music.
tt is also well known that some dogs howl when hearing par-
ticular tones.** 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.” %

‘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 physio-
logical principles why concords are agreeable, and discords dis-
agreeable to the human ear; but we are little concerned with
these, as music in harmony is alate invention. (We are more con-
cerned 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, é&c., all harmonies of the fundamental pre-
dominant 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 ihe 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 instruméntal music. As neither the enjoyment nor the
eapacity of producing musical notes are faculties of the least

33 Several accounts have been
published to this effect. Mr. Peach
writes to me that he has repeatedly
fcand that an old dog of his howls
when B flat is sounded on the flute,

snd to no other note. 1 may add

another instance of a dog always
whining, when one note on a con-
certina, which was out of tune, waa
played.

34 Mr. R. Brown, in ‘Proc. Zool
boc.’ 1868, p. 410.

570 Lhe Descent of Man. Part IL

ase to man iv reference tc 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, “ doubts
‘whether even amongst the nations of Western HBurope, in-
“timately connected as they are by close and frequent inter-
‘* course, the music of the one is interpreted in the same sense by
“the others. By travelling eastwards we find that there is cer-
“ tainly 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 he considered as the offspring of song, is like-
wise 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 Hot-
tentots 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 becn a
songster. It is more remarkable that parrots, belonging 10
a group distinct from the Irsessores, and having differently

35 «Journal of Anthropolog. Soc.’ cond edition, 1869, which contain
Det. 1870, p. clv. See also the an admirable account of the hvbita
several later chapters in Sir John — of savages,

Lubbock’s ‘Prehistoric Tlmes,’ se-

Unap, XIX, Man— Musical Powers. 571

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.** 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, &c. 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 obscrvcs,
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 com-
monest theme of our songs. As Herbert Spencer remarks,
“music arouses dormant sentiments of which we had not
“ couceived 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 ex-
pressed 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,
“ while the company, as if touched by a musical wave, murmur

3¢ Since this chapter was printed,
{ have seen a valuable article by
Mr. Chauncey Wright (‘North
Aimer. 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 use-
“ ful 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 impor-
tant bearing on the acquisition hy
man of some of his mental charac
teristics,

572 The Descent of Man. Part JIL,

"a chorus in perfect unigon.”*? Even monkeys express strong
feelings in different tones—anger and impatience by low;—fear
and pain by high notes.3® 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 an-
cestors, 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 ernotions 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 jn 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 deve-
loped from the tones used in impassioned speech. We must
suppose that the rhythms and cadences of oratory. are derived
from previously developed musical powers.*® 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,
nud, as remarked in a former chapter, believe that musical sounds
ufforded one of the bases for the development of language.”

37 Winwood Reade, ‘The Martyr- the opposite sex. Thus musical

dom of Man,’ 1872, p. 441, and
‘ African Sketch Book,’ 1873, vol. ii.
p. 313.

38 Rengger, ‘ Sdugethiere
Paraguay,’ s. 49.

39 See the.very interesting dis-
eussion on the ‘Origin and Function
of Music,’ by Mr. Herbert Spencer,
in his coilected ‘ Essays,’ 1858, p.
359. Mr. Spencer comes to an ex-
actly opposite conclusion to that at
which I have arrived. He con-
eludes, 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
aud rhythm were tirst acquired by
the male or female progenitors of
mankind for the sake of charming

von

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, uor 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 in-
teresting discussion on the relations
between poetry, recitative, and song.

401 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

Ona1, XIX, Man—Love of Ornament. 573

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 pro-
bable 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." 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 Man-
kind.—In civilised life man is largely, but by no means exclu-
sively, 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.” That they have

“articulate sounds, they were com-
* municated by tones, varied accord-
“ing to different degrees of gravity
“and acuteness.”

41 See an interesting discussion
on this subject by Hiickel, ‘ Gene-
velle Morph,’ B. ii. 1866, s. 246.

42 A full and excellent account of
the manner in whien savages in all
rarts of the world ornament them-

selves, is given by the Italian tra
veller, Prof. Mantegazza, ‘ Rio de la
Plata, Viaggi e Studi,’ 1867, pp.
525-545; all the following state-
ments, when other references are
not given, wre taken from this work.
See, akso, Waitz, ‘Introduct. to
Anthropolog.’ Eng. transl. vol. i.
1863, p. 275, et passim. Latvrence
also gives very full details in his

574 The Descent of Man.

Part IJIi,

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.”*8 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, &c. 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, &c., 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
“attvactions.” In the Arab countries no beauty can be perfect
unti: the cheeks “or temples have been gashed.”** In South
Amcrica, 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

‘Lectures on Physis ogy,’ 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
wad hair, and piercing thei> teeth.

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. 465.

41 «The Nile Tributaries,’ 1867;
‘The Albert N’yanza,’ 1866, vol. i
p. 218.

Cnap, XIX, Man—Love of Ornament. 575

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*® 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.”** 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. Tha
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*’ 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 bebolding
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 in-
serted 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.”

48 Quoted by Prichard, ‘Phys, 445. On the coiffure of the Afri
Ilist. of Mankind, 4th edit. vol. i. cans, Sir S. Baker, ‘The Albert
1851, p. 321. N’yanza,’ vol. i. p. 210.

46 On the Papuans, Wallace, 47 ¢ Travels,’ p. 523.

The Malay Archipelago,’ vol. ii. p.

576 The Descent of Man. Parr IIT.

The wife of the chief of Latooka told Sir S. Baker* 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 pe/elé, 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 ave the only beautiful things women have ; men have
«beards, women have none. What kind of a person would she
* ‘be without the pelelé? She would not be a woman at all
*€¢ with a mouth like a man, but no beard,”

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,’ and thus mutilations, from
whatever cause first made, soon come to be valued as distinctive
marks. But self-adornment, vanity, and the admiration ot
others, seem to be the commonest motives. In regard to tattoo-
ing, 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* 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.”

48 ¢The Albert N’yanza,’ 1866,
vol. i. p. 217.

‘9 Livingstone, ‘ British Associa-
tion,’ 1860; report given in the
‘Atheneum,’ July 7, 1860, p. 29.

50 Sir S. Baker (ibid. vol. i. p.
210) speaking uf 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 the invariability
of the tattooing of the Amazonian
Indians.

51 Rev. R. Taylor, ‘ New Zealand
and its Inhabitants,’ 1855, p. 152.

52 Mantegazza, ‘ Viaggi e Stuii,
p. 042.

Crap, XIX. Man—Beauty. 577

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 orna-
mented, 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, &c., 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 universai
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® 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. 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.

33 ¢Travels in S. Africa,’ 1824, ‘ Voyages,’ &. tom. ii. p. 116.
vol. i. p. 414. 55 On the vegetable productions
54 See, for references, Gerland used by the North-Western Ameri-
Ueber das Aussterben der Naturvél- can Indians, ‘ Pharmaceutical Jour-
cer,’ 1868, 8. 51.53, 555 also Azara, nal,’ vol. x.

38

578 The Descent of Man. Part IT],

Hearne,’* an excel.ent 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
“lat face, small eyes, high cheek-bones, three or four broad
“black lines across each check, 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 Mandschi form; that is to say, a broad face, high cheek-
* bones, very broad noses, and enormous ears;”*? 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 Hue 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 check-bones. It is, therefore, not wonderful that‘ beauty,
“ according to our notion is a stranger to them. Yet they con-
“ sider their own females to be much more beautiful than those
“ ot Europe.”#

It is well known that with many Hottentot women the
posterior part’of the body projects in a wonderful manner; they
uve steatopygous; and Sir Andrew Smith is certain that this
peculiarity is greatly admired by the men. He once saw a

s° +A Journey from Prince of furd and Finlayson, ‘ Phys. Hist. of

Waies Fort,’ 8vo. edit. 1796, p. 89.

57 Quoted by Prichard, ‘ Phys.
Hist. of Mankind,’ 3rd edit. vol. iv.
1R44, 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. 197.

§® Prichard as taken from Craw-

Mankind,’ vol. iv. pp. 534, 535,

5® Idem illustrissimus viator dixit
mihi precinctorium vel tabulam
foeminz, quod nobis teterrimum est,
quondam permagno estimari ab
hominibus in hac gente. Nruc rea
mutata est, et censent talem con-
formationem minime optandam ewe

Car, XIX, Man—Beauty. 579

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 pecu-~
liarity ; 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 @ tergo. Nothing can be more
« hateful to a negro than the opposite form.” ”

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 conforma-
“ tions.” Hein return praised the glossy jet of their skins and the
Jovely depression of their noses; this they said was, “ honey-
* mouth,” nevertheless they gave him food. The African Moors,
also, “ knitted their brows and seemed to shudder ” at the white-
ness 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 belicf
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 cbnsidered handsome
“throughout the whole country;” so that here we have a
different standard of taste. With the Kafirs, 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 Kafir. Ihave 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.” Mr. Galton, in speaking
to me about the natives of 8. Africa, remarked that their ideas of

‘The Anthropological Review,’
November, 1804, p. 237. For ad-
ditional references, see Waitz, ‘ ln-
troduct. to Anthropology,’ Eng.
trauslat., 1863, vol. i. p. 105.

6| Mungo Park’s ‘Travels in
Africa,’ 4to. 1816, pp. 53, 131.

Burton’s statement is quoted by
Schaaft hausen, ‘ Archiv fur Anthro-
polog.’ 1866, s. 163, On the Banyai,
Livingstone, ‘Travels,’ p. 34. On
the Katirs, the Rev. J. Shooter,
‘The Batirs of Natal and the Zulr
Country,’ 1857, p. L.

580 The Descent of Man. Part ILL

beauty seem very different from ours; for in cne 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.” In8S. America, the Yura-
caras, 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.”

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 8. 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 con-
sidered 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 he 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 hairs 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.

62 For the Javans and Cochin
Chinese, see Waitz, ‘Introduct. to
Anthropology,’ Eng. tzanslat. vol. i,
p. 305. On the Yura-caras, A.
d’Orligny, as quoted in Prichard,
‘Phys. Hist. of Mankind,’ vol. v. 3rd
edit. p. 476.

83 orth American Indiane,’ by

G, Catlin, 3rd edit. 1842, vol, i. p.
49; vol. ii. p. 227. On the natives
of Vancouver’s Islaad, see Sproat,
‘Scenes and Studies of Savage Life,’
1868, p. 25. On the Indians of
Paraguay, Azara, ‘ Voyages,’ tom. ii
p. 105,

Caav, XIX Man—Beauty. 581

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 Polynesiars,
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 isno 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.*

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.”® 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 archi-
pelagoes 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.” *

We thus see how widely the different races of man differ in
their taste for the beautiful. In every nation sufficiently ad-
vanced 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.” 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,

®4 On the Siamese, Prichard, ibid.
vol. iv. p. 533. On the Japanese,
Veitch in ‘Gardeners’ Chronicle,’
1860, p. 1104. On the New Zea-
sanders. Mantegazza, ‘ Viaggi e
Studi,’ 1867, p. 526. For the other
nations mentioned, see references in
Lawrence, ‘ Lectures on Physiology,’
&e. 1822, p. 272.

48 Lubbock, ‘Origia of Civilisa-

tion,’ 1870, p. 521.

66 Dr. Barnard Davis quotes Mr.
Prichard and others for these facts
in regard to the Polynesians, in
‘Anthropological Review,’ April,
1870, p. 185, 191.

§7 Ch. Comte has remarks to this
effect in his ‘Traité de Législation,
8rd edit. 1237, p. 136,

tae
ive)
Ww

The Descent of Man. Parr IL,

Mr. Winwood Reade, however, who has had ample oppor-
tunities 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. Rohifs writes
tc 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. ‘hey 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
pirl has been heard to say,“ I do not want to marry him, he has
“ eot 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. Notwithstand-
ing 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.®

The general truth of the principle, long ago insisted on by
Humboldt,” 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 8.
America, in order to exaggerate some natural and admired

8 The ‘African Sketch Book,’
vol. ii, 1873, pp. 253, 394, 521,
[he Fuegians, as [ have been in-
formed by a missionary who long
resided with them, consider Euro-
pean women as extremely beautiful ;
but trom what we have seen of the
judgment of the other aborigines of
America, I cannce but think that
this must be a mistake, unless in-
leed the statement refers to the few
Fuegians who have lived for some
time with Uuropeans, and who oust

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 che
world, ‘Anthropological Review,’
March, 1864, p, 245.

8° «Personal Narrative,’ Eng,
translat. vol iv. p. 518, and else-
where. Mantegazza, in his ‘ Viacgi
e Studi,’ 1867, strongly insists on
this sama principle.

{

Cuav. XiX. Man— Beauty.

583

peculiarity. Many American Indians ave 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
“ inereasing 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.”

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 fore-
heads 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. The Chinese have by nature un-
usually small feet;7 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 itmay 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

70 On the skulls of the American
tribes, see Nott and Gliddon, ‘Types
of Mankind,’ 1854, p. 440; Prichard,
‘Phys. Hist. of Mankind,’ vol. i.
3re edit. p. 321; on the natives of
Arakhan, ibid. vol. iv. p. 537.
Wilson, ‘ Physical Ethnology,’
Smithsonian Institution, 1863, p.
988: on the Fijians, p, 290. Sir
J. Lubbock (‘Prehistoric Times,’
trd edit. 1869, p. 506) gives an
ex‘eileut césamé on this subject.

71 On the Huns, Godron, ‘ De
PEspéce,’ tom, ii. 1859, p. 300
On the Tahitians, Waitz, ‘Anthro
polog.’ Eng. translat. vol. i. p. 305.
Marsden, quoted by Prichard, ‘ Phys,
Hist. of Mankind,’ 3rd edit. vol. v.
p. 67. Lawrence, ‘ Lectures om
Physiology,’ p. 337.

72 This fact was ascertained ia
the ‘Reise der Novara: Anthropolog,
Thiel,’ Dr. Weisbach, 1867, ». 265.

534 The Descent of Man. Parr UI.

“ vie with each other in the superlativeness of their own style.”
Dr. Wilsou, in speaking of the compressed skulls of various
American races, adds, “such usages are among the least eradi-
* cable, and long survive the shock of revolutions that change
“dynasties and efface more important national peculiarities.”
The same principle comes into play in the art of breeding;
and we can thus understand, as I have elsewhere explained,”
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” 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 cha-
racteristic carricd to a moderate extreme.”* 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.

78 «Smithsonian Institution,’ 1863,

p. 289. On the fashions of Arab
women, Sir S. Baker, ‘The Nile
Tributaries,’ 1867, p. 121. .
74 ¢The Variation of Animals and
Plints under Domestication,’ vol. i.
p. 214; vol. ii. p. 240.
™ Schaaffhausen, ‘Archiv — ftir

Anthropologie,’ 1866, s. 164.

76 Mr. Bain has collected (¢ Men-
tal and Moral Science,’ 1868, pp.
304-314) about a dozen more or
less different theories of the idea of
beauty; but none are quite the
same as that here given

Cap. XX. Man—Sexual Selection. 585

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 cha-
racters a little exaggerated beyond the then existing common
standard.

CHAPTER XX.
SEconDARY SEXUAL CHARACTERS OF MaNn—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 ;
aud that the men judge of the beauty of their women by widely
different standards. We must next inquire whether this pre-
ference 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 man-
kind 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 us far as the bodily frame is
suncerned. Civilised men are largely attracted by the mental
enarms 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 beautilul women, will
vot have a better chance of leaving a long line of descendants

586 The Descent of Man. Parr IIL.

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 philo-
sopher 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.”

There is, however, reason to believe that in certain civilised
and semi-civilised nations sexual selection has effected some~
thing 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 beau-
tiful 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 ohiely due
to their better food and manner of life.

The old traveller Chardin, in describing the iain says
their “ blood is now highly refined by frequent intermixtures
“ with the Georgians and Circassians, two nations which surpass
“ali 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
" yank in Persia, who are descendants of the Tartars, would be
* extremely ugly.”? Here is a more curious case; the priestesses

' «Schopenhauer and Darwinism,’ &c. 1822, p. 393), who attributes
in ‘Journal of Anthropology,’ Jan. the beauty of the upper classes in
1871, p. 323. England to the men having dong

? These quotations are taken from elected the more beautiful women.
Lawrence (‘ Lectures on Ph; sislogy,’

Guar. XX. Man—Checks to Sexual Selection. 587

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® 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 from its curiosity. Mr. Winwood Reade informs me that
the Jollofs, a tribe of negroes on the west coast of Africa, “ are
“ yemarkable 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 worse-looking slaves aud 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 ‘ 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 Cuus s 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,
ull 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 pro-
miscuous. Nevertheless all those who have most closely studied

3 ¢ Anthropologie,’ ‘Revue des Plants under Domestication,’ vol. i.
Cours Scientifiques,’ Oct. 1868, p. p. 207.
721. § Sir J. Lubbosk, ‘The Origin of
¢ ¢The Variation of Animals and Civilisation,’ 1870, chap. iii especi

§88 The Descent of Man. Parr Tif,

the subject,° 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
kuew much about the habits of savages there and elsewhere, ex-
pressed 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 recog-
nised 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
im 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

ally pp. 60-67. Mr. M‘Lennan, in

memoir on the classificatory system
bis extremely valuable work on

of relationship (‘ Proc. American

‘ 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 licentious-
ness of savages at the present time,
Mr. L. H. Morgan, in his interesting

Acad. of Sciences,’ vol. vii. Feb.
1868, p. 475), concludes that poly-
gamy and all forms of marriage
during primeval times were essen-
tially unknown. It appears also,
from Sir J. Lubbock’s work, that
Bachofen likewise believes that
communal intercourse originaily
prevailed.

Caar. XX, Man—Checks to Sexual Selection. 5890

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 abso-
lutely 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 tke 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,’ we can also thus understand “ the
“ necessity of expiation for marriage as an infringement of tribal
“ yites, 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

3 Address to British Association dition of the Lower Races of Man.:
On the Social and Religious Con- 1870, p. 20.

590 The Descent of Man. Past II

intelligible, if we admit that promiscuous intercourse was the
aboriginal, and therefore long revered custom of the tribe.’
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® 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 ex-
tremely 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 tkeir wives. Others are poly-
gamous, 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 somewhas
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 ina body, as with
several species of baboons.® 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

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.

®§ Mr. C. Staniland Wake argues
strongly (‘ Anthropologia,’ March,
1874, p. 197) against the views held
by these three writers on the formes
prevalence of almost promiscuous
§nsercouize; and he thinks that the

classificatory system of relationship
can be otherwise explained.

® Brehm (‘Illust. Theirleben,’ B.
i. p. 77) says Cynocephalus hama-
dryas lives in great troops contain-
ing twice as many adult females as
adult males. See Rengger on Aines
rican polygamous species, and Owen
(‘ Anat. of Vertebrates,’ vol. iii. p.
746) on American monogamous
species. Other references might be
added

€rar. XX. Man—Checks to Sexual Selection. Sy!

improbable. The pairing may not last for life, but only for each
birth; yet ifthe 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.” 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," “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 poly-
gamous 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.

Iufanticide-—This practice is now very common throughout
the world, and there is reason to believe that it prevailed much
more extensively during former times.” Barbarians find it

16 Dr. Savage, in ‘ Boston Journal 12 Mr. M*‘Lennan, ‘ Primitive
of Nat. Hist.’ vol. v. 1845-47, p. Marriage,’ 1865. See especially on
423. exogamy «and infanticide, pp. 150,

4 ¢ Prehistoric ‘Vimes,’ 1869, p. 188, 165,
424,

592 The Descent af Man. Past IE,

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 Poly-
nesian Islands women have beer 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. Wherever infanticide
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 estima-
tion set on them when few and their happier fate, are assigned
by the women themselves, and by various observers, as additional
motives for infanticide. In Australia, where female infanticide
is still common, Sir G. Grey estimated the proportion of native
women to men as one to three; but others say as two to three.
In a village on the eastern frontier of India, Colonel MacCulloch
found not a single female child.

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 origin-
ally 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 cratt, 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,

13 Dr. Gerland (‘Ueber das Aus- 54, Azara (‘ Voyages,’ &c. tom. ii,
aterben der Naturvélxer,’ 1868) has yp. 94, 116) enters in detail on the
collected much intormation on -a- motives. See also M‘Lennan (ibid
fanticide, see especially s. 27, 51, p. 139) for cases in India,

unap. XX. Aan—Checks to Sexual Selection. 593

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 * 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
amder these circumstances the women no doubt will have the
power of choice, and will prefer the more attractive men. Azayra,
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.”
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 Betrothuls 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

14 ¢ Primitive Marriage,’ p. 208; polyandry.
Sir J. Lubbock, ‘ Origin of Civilisa- 13 Azara, ‘ Voyages,’ ke. tom. ii
ticn,’ p. 100. See also Mr. Morgan, pp. 92-95, Colonel Marshall,
we, cit., on the former prevalence of ‘ Amougst the Todas, p. 212.

39

594 The Descent of Man. Parr IIL

which savages are exposed, and some of their habits, are favour-
able 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," and generally
marry whilst young. Consequently they must be subjected tb
occasional hard struggles for existence, and the favoured indi-
viduals 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
ot 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 defend-
ing their females, as well as their offspring, from enemies of all
kinds. At this early period the ancestors of man would not be
sufficiently udvanced 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 poly-
andry 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 pro-
miscuous 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 per-
mitted 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,

16 Burchell says (‘Travels in S. Azara (‘Voyages dans l’Amérique
Africa, vol. ii, 1824, p. 58), that Merid.’ tom. ii. 1809, p. 21) makes
among the wild nations of Southern precisely the same remark in regard
Africa, neither men acr women ever to the wild Indians of South Ame
pass their liver nm a state of celibacy. rica.

Cnar. XX. Man—Mode of Sexual Selection. 595

and all the offspring, as far as that was possible, would be reared ;
so that the struggle for existence would be periodically ex-
cessively 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 Seaual Selection vith Mankind.— With
primeval men. 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 in-
fanticide, early betrothals, &c. 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 speceed 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 uttractive 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 fapu to some
chief. With the Kafirs, as Mr. C. Hamilton states,” “ 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, orna-
ments, 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 inex-
plicable 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
wto a new country, or when a native breed is long and carefully

17 ¢ Anthropological Review,’ Jan. 1870, p. xvi

596 The Descent of Man. Paxt III,

attended to, either for use or ornament, it is found after several
generations to have ucdergone 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.1* 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; 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 allics the Qnadrnmana,
will almost certainly have been thus modified; and, as savages
still fight for the possession of their women, a similar process of

18 <The Variadion of Animals and French artists, that the idea of
Plants under Domestication,’ vol. ii, beauty is not absolutely the same
pp. 210-217. even tnroughout Europe: see the

© An ingenious writer argues, ‘Lives of Haydn and Mozart,’ br
‘rom a comparison of the pictures Bombet (otherwise M. Beyle)
of Raphael, Rubens, «ad modern English translat. p. 278.

Cuar. XX. Man—Mode of Sexnal Selection. 597

election has probably gone on in a greater or less degrce 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 heen preferred by
the females. There are, however, exceptional cases in which the
males are the selecters, instead of having been the selected. We
recognise such cases by the females being more highly orna-
mented 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 sur-
prising 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 deco-
rating themselves with all sorts of ornaments thando 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 succes-
sive 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 selecters, 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 becn
expected. As this is a point of some importance, I will give in
detail such evidence as I have been able to collect.

Fearne describes how a woman in one of the tribes of Arctic

598 The Descent of Man. Par? JIL

America ropeatedly 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 wifc, bargains with the parents about the price. But
“it frequently happens that the girl rescinds what has been
“aereed upon between the parents and the bridegroom,
* obstinately rejecting the very mention of marriage.” She often
tucs 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
“ig 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; ‘‘ butif 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 kuown to fail in getting
wives. The girls, before consenting ta 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 Bush-
tocn of S. Africa, “when a girl has grown up to womanhood

Cnar. XX. Man—Mode of Sexual Selection. 599

« without having been betrothed, which, however, does not often
“happen, her lover must gain her approbation, as well as that of
“the parents.” 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 tomarry 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 supportthem. 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 charac-
ters 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 nced 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

20 Azara, ‘Voyages,’ &c. 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, ‘ Voy-
ages of the Adventure and Beagle,’
vol. ii. 1839, p. 182. On the Kal-
saucks, quoted by M‘Lenaan, ‘ Pri-

mitive Marriage,’ 1865, p. 32. On
the Malays, Lubbock, ibid. p. 76.
The Rev. J. Shooter, ‘On the Katirs
of Natal,’ 1857, pp. 52-60. Mr. D.
Leslie, ‘Katir Character and Customs,’
1871, p. 4. On the Bush-men,
Burchell, ‘Travels in S. Africa,’
vol. ii. 1824, p. 59. On the Kozaks
by McKennan, as quoted by Mr.
Wake, in ‘ Anthropologia,’ Oct. 1373,
p. 75.

600

The Descent of Man. Pant JJJ,

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 rian have likewise been
already discussed.

absence of Hat 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.“ 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 some
times, as with the male mandrill and female rhesus, much more
vividiy 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, how-
ever, appears to have been removed, not for the sake of nudity,
but that the colour of the skin may be more fully displayed. So

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 hair-
wss condition of the skin as coming
under this head. The Rev. T. R.
Stebbing, in commenting on this

view (‘Transactions of Devonshire
Assoc. for Science,’ 1870) remarks,
that had Mr. Wallace “ employed
“his usual ingenuity on the ques-
“ticn of man’s hairless skin, he
“might have seen the possibility of
“its selection through its superior
“beauty or the health attaching te
“ superior cizanliness.”

Onar. XX, Man—A bsence of Hair. 601

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 feinale 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 bairy 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 eharacter to her young off:
spring of both sexes.”

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 othcr characters to a lower animal type. It
does not appear that a culd climate has been influential in
leading to this kind of reversion; excepting perhaps with the

% <The Variation of Animals and Plants under Domestication,’ gol. 21,
1868, p. 327.

602 The Descent of Man. Paar III

neyroes, who have been reared during several generations in
the United States?* and possibly with the Ainos, who inhabit
the northern islands of the Japan archipelago. But the laws ot
inheritance are so complex than 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.”

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 sv, to their offspring of
both sexes. We know from Eschricht® 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

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 batning; and by
looking to the published table, “ it
“is manifest at a glance that there
“is but little, if any, difference be-
“tween the white and the black
“races in this respect.” It is, how-
ever, certain that negrces in their na-
tive and much hotter land of Africa,
have remarkably smooth bodies, It
should be particularly observed,
that both pure blacks and mu-
lattoes were included .n the above
anumeration; and thisis an unfor-
tunate circumstance, as in accordance
with a principle, the trutn of which
§ have elsewhere proved, crossed

races of man would be eminently
liable to revert to the primordial
hairy character of their early ape-
like progenitors.

*4 Hardly any view advanced in
this work has met with so much
disfavour (see for instance, Spengel,
‘Die Fortschritte des Darwinismus,’
1874, p. 80) as the above explana-
tion ofthe toss 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 Quad-
rumana.

** «Ueber die Richtung der
Haare am Menschlichen Ko: per,’
in Miiller’s ‘Archiv fur Anat. und
Phys.’ 1837, 5. 40.

CuaP, XN.

Beards. 603

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 mankiud; and it is possible that only the
later stages of development have been retained by man. {n
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 iailed 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-Séquard 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”
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.” Nevertheless with man-
kind, 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”® 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 extra-
ordinary difference in the length of the hair in the different
races; in the negro the hair forms a mere curly mat; with us

24 ¢On the tail-feathers of Momo- Some distinguished “ethnologists,

tus’ ‘Proc. Zooicg. Soc., 1873, p.
429.

21 Mr. Sproat has suggested
(‘Scenes and Studies of Savage
Life,’ 1868, p. 25) this same view.

amongst others M. Gosse of Geneva,
believe that artificial modifications
ot the skull tend to be inherited.

2% ‘Ueber die Richtung,’ ibic. a
qu.

604 The Descertt of Man. Past TIL.

it is of great length, and with the American natives it nut rarely
reaches to the gruund. Some species of Semnopithecus have
their heads covered with moderately long hair, and this probably
serves as an ornument 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, .t is a glory to her;” and we
have seen that in North Amcrica 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 themen ofall 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
adinire 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 minature of Pithecia
satunas 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 tbe order of development during growth, generally
indicates the order im which the characters of a species havo
been developed and moditied durivg 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.

Crap, XX, Summary on Man. 605

Summury.—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 subse-
quently been auginented, 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 moditied 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 latertimes. 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 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 sexua! selection. We have
seen that with tha lowest savages the people of each tribe admire

506 The Descent of Man. Part Ill.

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—

Cua, XXI. General Summary. 607

are facts which cannot be disputed. They have long boen
known, but until recently they told us nothing with respect to
the origin of man. Now when viewed by the light of our know-
ledge of the whole organic world, their meaning is unmistakable.
The great prinviple of evolution stands up clear and firm, when
these groups of 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 séen that man incessantly presents individual differ-
ences 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 the lower animals.
In both cases similar laws of inheritance prevail. Man tends to
increase at a greater rate than his means of subsistence; con-
sequently 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 selec-
tion; 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
woisture; and lastly, many characters of slight physiologicsl

608 The Descent of Man. Parr TL

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 peculiarites 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 modi-
fications, 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 progenitér; and a pro-
genitor 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 hie
stock, and unconscionslv forms a new strain. So with respect

Cnar, XX. General Summary. 609

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 heen examined by a
naturalist, would have been ciassed 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 branchie, 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 larvee
of the existing marine Ascidians than any other known form.

The high standard of our intellectual powers and moral dis-
position 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 inheriled. 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. Thesame conclusion may be extended to man;
tbe intellect must have been all-important to him, even at a vory

40

610 The Descent of Man. Part 1It

remote period, as enabling him to invent and use language, to
taake weapons, tools, traps, &c., whereby with the aid of his
social habits, he long ago became the most dominant of ail 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! 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 toe
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, &c., probably follow from the con-
tinued 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 im-
portant elements are love, and the distinct emotion of sympathy.
Animals endowed with the social instincts take pleasure in one
unother’s company, warn one another of danyer, 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
tollows, firstly, from the enduring and ever-present nature of the
social instincts; secondly, from man’s appieciation of the appro-
bation and disapprobation of his fellows; and thirdly, from the
high activity of his mental faculties, with past impressions ex-
tremely vivid; and in these latter respects he differs from the
fower animals. Owing to this condition of mind, man cannct

> “On the Limits of Natural Selection, in the ‘Neith Americaa
Review,’ Oct. 1870, p. 295,

nar. XXI, General Sui.mary. 611

avoid looking both backwards and forwards, and comparing
past impressions. Hence after some temporary desire or passion
bas 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 dissatis-
faction 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 becomea 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-happiness 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 indi-
vidual, 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 censcience. This affords the strongest argument for educating
and stimalating in all possible ways the iutellectual facultics uf

612 The Descent of Man. Part HL

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, wili
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 avimals. 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
eud 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 trom some low
organised form, will naturally ask how does this bear on the beliet
in the immortality of the soul. The barbarous races of man, ag
Bir J. Lubbeck has shewn, possess no clear belief of this kind‘

Cuar. XXI. General Summary. 613

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.?

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 ig 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,

2 ‘The Rev. J. A. Picton gives discussion to this effect in his ‘New
Theories and the Old Faith,’ 1870.

S14 The Descent of Alan. Part III,

and are endowed with the requisite qualities of courage and
puguacity. They are provided, either exclusively or in a much
higher degree than the females, with crgans for vocal or instru-
mental music, and with odoriferous glands. They are ornamented
with infinitely diversified appendages, and with the most
hrilliant 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
curing 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 through-
out 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 the
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, bul
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

Cnar, XXL General Summary. 615

same sex, or to both; as wellas 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 propaga-
tion 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; aud 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
eases 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 quad-
rupeds 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, charac-
terised 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

516 The Descent of Man. Parr lil

larger number of offspring to inherit their superiority in orna-
ments or other charms than the less attractive males; but J
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
tirae the more vigorous and victorious males.

Although we have some positive evidence that birds appre-
ciate 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 ustonishing 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 wonder-
ful than that the female Argus pheasant should appreciate the
exquisite shading of the ball-and-socket ornaments and the
elegant patterns on the wing-feathers 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 appre-
ciating 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 zsthetic 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
fools great difficulty in admitting that female mammals, birds.

Unar, XXI. General Summary. 617

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 distinet
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. Ifhe 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 quatities. 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

618 The Descent of Man. Parr 17]

will never be even partially realised until the Jaws of inheritance
are thorcughly known. Everyone does good service, who aids
towards this end. When the principles of breeding and in-
heritance 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 prudeut 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 naturs
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, &c., 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 aston-
ishment which I felt on first seeing a party of Fuegians on a
wild and broken shore will never be forgotten by me, for the
vefiection 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 excite-
ment, and their expression was wild, startled, and distrustful,

Cuap, XXI. General Summary. 619

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
croature 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, practises 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 surnmit of the
organic scale; and the fact of his having thus risen, instcad 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 Ihave 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.

ABBOTT.

AGBION,

A.

Abbot, C., on the battles of seals,
500.

Abductor of the fifth metatarsal,
presence of, in man, 42.

Abercrombie, Dr., on disease of the
brain affecting speech, 88.

Abipones, marriage customs of the,
5y8.

Abou-Simbel, caves of, 168.

Abortion, prevalence of the practice
of, 46.

Abstraction, power of, in animals, 83.

Acalles, stridulation of, 306.

Acanthodactylus capensis, sexual dif-
ferences of colour in, 357.

Accentor modularis, 473.

Acclimatisation, difference of, in dif-
ferent races of men, 167.

Achetidz, stridulation of the, 282,
283, 285 ; rudimentary stridulating
organs in female, 288.

Acilius sulcatus, elytra of the female,
276.

Acomus, development of spurs in the
female of’, 450,

Acridiide stridulation of the, 282,
286; rudimentary stridulating or-
gans in female, 288,

Acromio-basilar muscle, and quad-
rupedal gait, 42.

Acting, 178.

Actinie, bright colours of, 260.

Adams, Mr., migration of birds, 108;
intelligence of nut-hatch, 418; on
the Bombycilla carolinensis, 461.

Admiral butterfly, 312.

Adoption of the young of other ani-
mals by female monkeys, 70.

Advancement in the organic scale,
Von Baer’s definition of, 164.

Aeby, on the difference between the

skulls of man and the quadrumana,
149,

Esthetic faculty, not highly deve-
loped in savages, 93.

Affection, maternal, 70; manifestation
of, by animals, 70; parental and
filial, partly the result of natural
selection, 105; mutual, of birds,
410; shewn by birds in confine-
ment, for certain persons, 411.

Africa, probably the birthplace of
man, 155; South, crossed popula-
tion of, 174; South, retention of
colour by the Dutch in, 193; South,
proportion of the sexes in the but-
terflies of, 250 ; tattooing practised
in, 574; Northern, coiffure of
natives of, 575. :

Agassiz, L., on conscience in dogs,
103; on the coincidence of the
races of man with zoological pro-
vinces, 169; on the number of
species of man, 174; on the court-
ship of the land-snails, 262; on the
brightness of the colours of male
fishes during the breeding season,
340; on the frontal protuberance
of the males of Geophagus and
Cichla, 340, 345; male fishes
hatching ova in their mouths, 345 ;
sexual differences in colour of chro-
mids, 345; on the slight sexual
differences of the South Americans,
561; on the tattooing of the Ama-
zonian Indians, 576.

Age, in relation to the transmission
of characters in birds, 463; va-
riation in accordance with, in birds,
484.

Agelaus pheniceus, 225, 416.

Ageronia feronia, noise produced } y.
307.

Agrion, dimorphism in. 290

AGRION.

INDEX.

ANTELOPE, 621

agrion Ramburit, sexes of, 290.

Agrionidz, difference in the sexes of,
290.

Agrotis exclamationis, 316.

Ague, tertian, dog suffering from, 8.

Aithurus polytmus, young of, 487.

Ainos, hairiness of the, 560.

Albino birds, 419.

Alca torda, young of, 486.

Alces palmata, 515.

Alder and Hancock, MM., on the
nudi-branch mollusca, 264.

Allen, J. A., vigour of birds earliest
hatched, 212, 2133 effect of dif-
ference of temperature, light, &c.,
on birds, 225; colours of birds,
4223; on the relative size of the
sexes of Callorhinus ursinus, 515;
on the mane of Otaria jubata, 521;
on the pairing of seals, 523; on
sexual differences in the colour of
bats, 534.

— S., on the habits of Hoplo-
pterus, 366; on the plumes of
herons, 391; on the vernal moult
of Herodias bubulcus, 393,

Alligator, courtship of the male, 221,
3515 roaring of the male, 567.

Amadavat, pugnacity of male, 346.

Amadina Lathami, display of plumage
by the male, 402.

castanotis, display of plumage
by the male, 402,

Amazons, butterflies of the,
fishes of the, 343.

America, variation in the skulls of
aborigines of, 26; wide range of
aborigines of, 169; lice of the
natives of, 170; general beardless-
ness of the natives of, 560.

-——, North, butterflies of, 250;
Indians of, women a cause of strife
among the, 561; Indians of, their
notions of female beauty, 577,
580.

~——,, South, character of the natives
of, 168; population of parts of,
173; piles of stones in, 179; ex-
tinction of the fossil horse of, 191;
desert-birds of, 490; slight sexual
difference of the aborigines of, 561;
prevalence of infanticide in, 592.

american languages, often highly
artificial, 91.

Americans, wide geographical range

250;

of, 29; native, variability of, 174;
and negroes, difference of, 197;
aversion of, to hair on the face, 580.

Ammophila, on the jaws of, 275.

Ammotragus tragelaphus, hairy fore
legs of, 531, 533,

Amphibia, affinity of, to the ganoid
fishes, 159; vocal organs of the,
566.

Amphibians, 165, 348;
whilst immature, 485

Amphioxus, 159.

Amphipoda, males sexually mature
while young, 485,

Amunoph IIL, negro character of
features of, 168.

Anal appendages of insects, 275.

Analogous variation in the plumage of
birds, 385.

Anas, 462.

acuta, male plumage of, 393,

boschas, male plumage of, 393-

—— histrionica, 484.

punctata, 374,

Anastomus oscitans, sexes and young
of, 486; white nuptia) plumage of,
492.

Anatide, voices of, 374.

Anax junius, differences in the sexes
of, 290.

Andaman islanders, susceptible 10
change of climate, 188.

Anderson, Dr., on the tail of Macacus
brunneus, 59; the Bufo sikimmen-
sis, 349; sounds of Echis curinata,
353.

Andrena fulva, 292.

«Anglo-Saxons, estimation of the beard
among the, 581.

Animals, domesticated, more fertile
than wild, 45; cruelty of savages
to, 118; characters common to
man and, 146; domestic, change of
breeds of, 596.

Annelida, 264; colours of, 265,

Anobium tessellatum, sounds produced
by, 306.

Anolis cristatellus, male, crest of, 354 ;
pugnacity of the male, 354; throat-
pouch of, 354.

Anser canadensis, 416.

cygnoides, 415 ; knob at the base

of the beak of, 426.

hyperboreus, whiteness of, 492

Antelope, prong-horned, horns of, 234

breeding

622 ANTELOPES,

INDEX,

ARDEA,

Antelopes, generally polygamous, 217;
horns of, 234, 504; canine teeth of
some male, 502; use of horns of
509; dorsal crests in, 530; dew-
laps of, 531; winter change of two
species of, 543; peculiar markings
of, 543.

Antenne, furnished with cushions in
the male of Penthe, 276.

Anthidium manicatum, large male of,
279.

Anthocharis cardamines, 308, 312;
sexual difference of colour in, 322.

genutia, 312.

sara, 312.

Anthophora acervorum, large male of,
279,

retusa, difference of the sexes in,
292.

Anthropida, 152.

Anthus, moulting of, 392.

Antics of birds, 380.

Antigua, Dr. Nicholson’s observations
on yellow fever in, 195.

Antilocapra americana, horns of, 234,
504, 507.

Antilope bezoartica. horned females of,
505, 506, 5073 sexual difference in
the colour of, 535.

Dorcas and euchore, 504.

euchore, horns of, 509.

montana, rudimentary canines in

the young male of, 514.

niger, sing sing, caama, and gor-

gon, sexual differences in the colours

of, 536.

oreas, horns of, 254.

saiga, polygamous habits of, 217.

—— strepsiceros, horns of, 234.

—— subgutturosa, absence of sub-
orbital pits in, 529,

Antipathy, shewn by birds in confine-
ment, to certain persons, 411.

Ants, 147; large size of the cerebral
ganglia in, 54; soldier-, large jaws
of, 63; playing together, 69;
memory in, 743 intcommunication
of, by means of the antenne, 89;
habits of, 147; difference of the
sexes in, 292; recognition of each
other by, afier separation, 292,

—— White, habits or, 291.

Anura, 349.

Anat nia muliebris, male unknown,
Cod.

Apathus, difference of the sexes ia,
292.

Apatura Tris, 307, 308.

Apes, ditterence of the young, froia
the avu.t, 8; semi-erect attitude ot
some, 5° 3 mastoid processes of, 53;
influences of the jaw-muscles on
the physiognomy of, 54; female
destitute of large canines, 63;
building platforms, 82; imitative
faculties of, 129; anthropomor-
phous, 153; probable speedy ex-
termination of the, 156; Gratiolet
on the evolution of, 1773; canine
teeth of male, 502; females of
some, Jess hairy beneath than the
males, 601.

long-armed, their mode of pre-
gression, 52.

Aphasia, Dr. Bateman on, 88,

Apis mellifica, large male of, 279.

Apollo, Greek statues of, 581,

Apoplexy in Cebus Azare, 7.

Appendages, anal, of insects, 276.

Approbation, influence of the love of,
109, 116, 131. :

Aprosmictus scapu/atus, 457.

Ajus, proportion of sexes, 255,

Aquatic birds, frequency of white
plumage in, 495.

Aquila chrysaétos, 408.

Arab women, elaborate and peculiar
coiffure of, 583.

‘Arabs, fertility of crosses with other
races, 171; gashing of cheeks and
temples among the, 574,

Arachnida, 272.

Arakhan, artiticial widening of the
forenead by the natives of, 583.

Arboricola, young of, 468.

Archeopteryx, 158.

Arctiidae, coloration of the, 314.

Ardea asha, rufescens, and ce#rulen,
change of colour in, 494, 495,

cerulea, breeding in immature

plumage, 484.

gularis, chauge of plumage in,

495.

herodias, love-gestures of the

male, 380.

ludoviciana, age of mature pla-
mage in, 483; continued growth
of crest and plumes in the male of
485. :

—— rycticerax, cries of, 368.

ARDEOLA,.

INDEX.

AUSTRALIA.

623

Ardeola, young of, 468.

Ardetta, changes of plumage in, 461.

Argenteuil, 22.

Argus pheasant, 384, 403, 462; dis-
play of plumage by the male, 398;
ocellated spots of the, 428; grada-
tion of characters in the, 434.

Argyll, Duke of, on the physical
weakness of man, 63; the fashion-
ing of implements peculiar to man,
82; on the contest in man between
right and wrong, 125; on the pri-
mitive civilisation of man, 143; on
the plumage of the male Argus
pheasant, 398; on Urosticte Ben-
jamini, 442,443; on the nests of
birds, 453,

Argynnis, colouring of the lower sur-
tace of, 314.

Aricoris epitus, sexual differences in
the wings of, 277.

Aristocracy, increased beauty of the,
58A,

arms, proportions ofyin soldiers and
sailors, 32; direction of the hair on
the, 151.

and hands, free use of, indi-
rectly correlated with diminution
of canines, 53.

Arrest of development, 35, 36.

Arrow-heads, stone, general resem-
blance of, 179.

Arrows, use of, 179.

Arteries, variations in the course of
the, 26.

Artery, effect of tying, upon the
lateral channels, 32.

Arthropoda, 268.

Arts practised by savages, 179.

Ascension, coloured incrustation on
the rocks of, 263,

Ascidia, affinity of the lancelet to,
159; tadpole-like larvae of, 159.
Ascidians, 262; bright colours of

some, 200.

Asinus, Asiatic and African species of,
548.

— teniopus, 548.

Ass, coluur-variations of the, 547.

Ateles, effects of brandy on an, 7;
absence of the thumb in, 51.

— beelzebuth, ears of, 15.
marginatus, colour of the ruff
of, 537; hair on the head of, 649.

Ateuchus, stridulation ot, 306.

Ateuchs, cicatricosus, habits of, 300.
Athalia, proportions of the sexes in,
254,

Atropus pulsatorius, 291.

Attention, manifestations of, in ani
mals, 73.

Audouin, V., on a hymenopterous pa-
rasite with a sedentary male, 221.
Audubon, J. J., on the pinioned goose,
105; on the speculum of Aergua
cucullatus, 236; on the pugnacity
of male birds, 362, 366; on Zetrao
cupido, 367; on Ardea nycticorac,
368 ; on Sturnella ludoviciana, 368:
on the vocal organs of etrao
cupido, 371; on the drumming of
the male Jvtrao umbellus, 375; on
sounds produced by the nightjar,
376; on Ardea herodias and Cath-
artes jota, 380; on Mimus polj-
glottus, 393; on display in male
birds, 394; on the spring change of
‘colour in some finches, 394; recog-
nition of a dog by a turkey, 412;
selection of mate by female birds,
416; on the turkey, 411, 412, 419;
on variation in the male scarlet
tanager, 424; on the musk-rat,
542; on the habits of Pyranya
estiva, 453; on local differences in
the nests of the same species of
birds, 456 ; on the habits of wood-
peckers, 458; on Bombyciila caro-
finensis, 461; on young females of
Tyranga estiva acquiring male cha-
racters, 462; on the immature
plumage of thrushes, 464; on the
immature plumage of birds, 465 e¢
s¢7. ; on birds breeding in immature
plumage, 484; on the growth of
the crest. and plumes in the male
Ardea ludoviciana, 485; on the
change of colour in some species of

Ardea, 494

Audubon and Bachman, M.M., on
squirrels fighting, 500; on the
Canadian lynx, 521.

Aughey, Prot., on rattlesnakes, 353,

Austen, N.L., on Anolis cristutelius,
354.

Australia, not the birthplace of man,
155; half-castes killed by the
natives of, 170; lice of the natives
of, 170; prevalence of feraale ite
tanticide in, 592,

524 AUSThALIA.

INDEX.

BARRINGTON.

Australia, South, variation in the
skulls of aborigines of, 26.

Australians, colour of newborn chil-
dren of, 557; relative height of the
sexes of, 559; women a cause of
war among the, 561.

Axis deer, sexual difference in the -
colour of the, 537.

Aymaras, measurements of the, 34;
no grey hair among the, 559;
hairlessness of the face in the, 561 ;
loug hair of the, 580.

Azara, on the proportion of men and
women among the Guaranys, 244 ;
on Falamedea cornuta, 366; on the
beards of the Guaranys, 561; on
strife for women among the Guanas,
561; on infanticide, 577, 592; on
the eradication of the eyebrows and
eyelashes by the Indians of Para-
guay, 580; on polyandry among
the Guanas, 593; celibacy unknown
among the savages of South Ame-
rica, 594; on the freedom of
divorce among the Charruas, 598.

B.

Babbage, C., on the greater proportion
of ilJegitimate female births, 244.

Babirusa, tusks of the, 518.

Baboon, revenge in a, 69; rage ex-
cited in, by reading, 71; manifes-
tation of memory by a, 74; em-
ploying a mat for shelter against
the sun, 82; protected from punish-
ment by its companions, 103.

——, Cape, mane of the male, 521;
Hamadryas, mane of the male,
521.

Buboons, effects of intoxicating li-
quors on, 7; ears of, 15; diversity
of the mental faculties in, 27; hands
of, 50; habits of, 51; variability
of the tail in, 58; manifestation of
maternal affection by, 70; using
stones aad sticks as weapons, 81 ;
co-operation of, 101; silence of, on
plundering expeditions, 104; ap-
parent polygamy of, 2173; poly-
gamous and social habits of, 590.

Bachman, Dr., on the fertility of mu-
lattoes, 171.

Baer, K. E. von, on embryonic deve-

lopment, 9.

Bagehot, W., on the social virtuer
among primitive men, 117 ; slavery
formerly beneficial, 117; on the
value of obedience, 130; on humaa
progress, 132; on the persistence
of savage tribes in classical times,
183.

Bailly, E. M., on the mode of fighting
of the [talian buffalo, 508; on the
fighting of stags, 510.

Bain, A., on the sense of duty, 98;
aid springing from sympathy, 103;
on the basis of sympathy, 106; on
love of approbation, &c., 109; on
the idea of beauty, 584.

Baird, W., on a difference in colour
between the males and feinales of
some Entozoa, 260.

Baker, Mr., observation on the pro-
portion of the sexes in pheasant-
chicks, 247.

, Sir S., on the fondness of the
Arabs for discordant music, 380; on
sexual differerce in the colours of
an antelope, 536; on the elephant
and rhinoceros attacking white or
grey horses, 540; on the disfigure-
ments practised by the negroes,
541; on the gashing of the cheeks
and temples practised in Arab
countries, 574; on the coiffure of
the North Africans, 575; on the
perforation of the lower lip by tie
women of Latooka, 575; on the
distinctive characters of the coiffure
of central African tribes, 5763; on
the coiffure of Arab women, 584,

“Balz” of the Black-cock, 363, 405.

Bantam, Sebright, 211, 238.

Banteng, horns of, 505; sexual dif-
ferences in the colours of the, 536.

Banyal, colour of the, 579.

Barbarism, primitive, of civilised
nations, 143.

Barbs, filamentous, of the feathers,
in certain birds, 385, 430.

Barrago, F., on the Simian resem-
blances of man, 3.

Barr, Mr., on sexual preference in
dogs, 524,

Barrington, Daines, on the lauguage
of birds, 86; on the clucking of
the hen, 368; on the object of the
song of birds, 369; on the singing
of female birds, 370; on birds

BARLOW.

INDEX.

BEDDOL

625

acquiring the songs of other birds,
370; on the muscles of the larynx
in song birds, 571; on the want of
tle power of song by female birds,
459,

Barrow, on the widow-bird, 403.

Bartels, Dr., supernumerary mamma
in men, 37.

Bartlett, A. D., period of hatching of
birds’ eggs, 165; on the tragopan,
220; on the development of the
spurs in Crossoptilon auritum, 236 ;
on the fighting of the males of
Plectropterus gambensis, 364; on
the knot, 391; on display in male
birds, 394; on the display of plu-
mage by the male Folyplectron,
396 ; on Crossoptilon auritum and
Phasianus Wallichii, 400; on the
habits of Lophophorus, 420; on the
colour of the mouth in Buceros
bicornis, 426; on the incubation of
the cassowary, 478; on the Cape
Buffalo, 508; on the use of the
horns of antelopes, 509; on the
fighting of male wart-hogs, 520;
on Ammotragus tragelaphus, 531;
on the colours of Cercopithecus
cephus, 537; on the colours of the
faces of monkeys, 550;. on the
naked surfaces of monkeys, 600.

Bartram, on the courtship of the
male alligator, 351.

Basque language, highly artificial, 91.

Bate, C. S., on the superior activity
of male crustacea, 221; on the
proportions of the sexes in crabs,
255; on the chele of crustacea,
266; on the relative size of the
sexes in crustacea, 268; on the
colours of crustacea, 270.

Bateman, Dr., tendency to imitation
in certain diseased states, 72; on
Aphasia, 88. :

Bites, H. W., on variation in the
form of the head of Amazonian
Indians, 28; on. the proportion of
the sexes among Amazonian but-
terflies, 250; on sexual differences
in the wings of buttertlies, 277;
on the field-cricket, 283; on
Pyrodes pulcherrimus, 294; on the
horns of Lamellicorn beetles, 295,
297; on the colours of /picalia,
te., 302; on the coloration of

41

tropical butterflies, 3113 on the
variability of Papilio Sesostris and
Childrene, 320; on male and fe-
male butterflies inhabiting ditferent
stations, 321; on mimicry, 323;
on the caterpillar of a Sphing, 325;
on the vocal organs of the um-
brella-bird, 3743. on the toucans,
492; on Brachyurus calvus, 550.

Batokas, knocking out two upper in-
cisors, 575.

Batrachia, 349; eagerness of male,
221,

Bats, scent-glands, 529: sexual dif-
ferences in the colour of, 534; fur
of male frugivorous, 534.

Battle, law of, 144; among beetles,
299; among birds, 360; among
mammals, 500 et seg.; in man,
561.

Beak, sexual difference in the forms of
the, 359; in the colour of the, 383.

Beaks, of birds, bright colours of, 491.

Beard, development of, in man, 557;
analogy of the, in man and the
quadrumana, 558; variation of the
development of the, in different
races of men, 559; estimation of,
among bearded nations, 5815; pro-
bable origin of the, 602.

, in monkeys, 150; of mammals,
531,

Beautiful, taste for the, in birds, 410,
in the quadrumana, 540.

Beauty, sense of, in animals, 92; ap-
preciation of, by birds, 413; in-
fluence of, 573, 576 ; variability of
the standard of, 596.

Beavan, Lieut., on the development
of the horns in Cervus /ldi, 234.
Beaver, instinct and intelligence of
the, 67, 68; voice of the, 527;

castoreum of the, 529.

Beavers, battles of male, 500.

Bechstein, on female birds choosing
the best singers among the males,
368 ; on rivalry in song-birds, 369 ;
on the singing of female birds, 37u ;
on birds acquiring the songs of
other birds, 370; on pairing the
canary and siskin, 415; on a subs
variety of the monk pigeon, 427;
on spurred hens, 449,

Beddoe, Dr., on causes of dillurence in
stature, 31,

BEE-EATUR.

626

INDEX.

BIRDS,

Bee-euter, 371.

Bees, 99; pollen-baskets and stings
of, 63; destruction of drones and
queens by, 106; female, secondary
sexual characters ot, 208; propor-
tion of sexes, 2543; difference of
the sexes in colour and sexual
selection, 292.

Beetle, luminous larva of a, 277.

Beetles, 294; size of the cerebral
gunglia in, 543 dilatation of the
fore tarsi in male, 275; blind, 294;
stridulation of, 301.

Belgium, ancient inhabitauts of, 182.

Bell, Sir C., on emotional muscles in
man, 3; “snarling muscles,” 41;
on the hand, 51.

, T., on the numerical proportion
of the sexes in moles, 247; on the
newts, 348; on the croaking of the
frog, 350; on the difference in the
coloration of the sexes in Zootoca
vivipara, 357; on moles fighting,
500.

Bell-bird, sexual difference in the
colour of the, 389.

Bell-birds, colours of, 492,

Belt, Mr., on the nakedness of tropical
mankind, 57; on a spider-monkey
and eagle, 102; habits of ants, 147 ;
Lampyride distasteful to mammals,
277; mimicry of Leptalides, 325;
colours of Nicaraguan frogs, 349;
display of humming-birds, 443; on
the toucans, 492; protective co-
louring of skunk, 543.

Benevolence, manifested by birds,
411,

Bennett, A. W., attachment of mated
birds, 411; on the habits of Dro-
mous trroratus, 478.

—., Dr, on birds
396.

Berbers, fertility of crcases with
other races, 171.

Bernicla antarctica colours of, 492.

Bernicle gander paizing with a Canada
goose, 414,

Bert, M., crustaceans
colours, 271.

Bertillon, M., arrested development
and polydactylism, 37.

Bettoni, E., on local differences in
the nests of Italian birds, 456.

Bayle, M., see Bombet.

of paradise,

distinguish

Bhoteas, colour of the beard in, 558,

Bhringa, discitorm tail-teathers of,
392,

Bianconi, Prof., on structures as ex-
plained through mechanical prin-
ciples, 24.

Bibio, sexual differences in the genus,
280.

Bichat, on beauty, 585.

Bickes, proportion of sexes in man,
243,

Bile, coloured, in many animals, 261,

Bimana, 149.

Birds, imitations of the songs of other .
birds by, 73; dreaming, 74; killed
by telegraph wires, 80; language
of, 863; sense of beauty in, 92;
pleasure of, in incubation, 103;
male, incubation by, 163; and rep-
tiles, alliance of, 165; sexual dif-
ferences in the beak of some, 208;
migratory, arrival of the male be-
fore the female, 212; apparent
relation between polygamy and
marked sexual differences in, 220;
monogamous, becoming polygamous
under domestication, 220; eager-
ness of male in pursuit of the fe-
male, 221; wild, numerical propor-
tion of the sexes in, 247 ; secondary
sexual characters of, 358; differ-
ence of size in the sexes of, 362;
fights of male, witnessed by females,
367; display of male, to captivate
the females, 3673; close attention
of, to the songs of others, 368 ; ac-
quiring the song of their foster-
parents, 370; brilliant, rarely good
songsters, 371; love-antics and
dances of, 380; coloration of, 385
et seq.; moulting of, 390 e¢ seq. ;
unpaired, 407; male, singing out
of season, 409; mutual affection of,
410; in confinement, distinguish
persons, 411; hybrid, production
of, 414; Albino, 419; European,
number of species of, 422; varia-
bility of, 422; geographical distri-
bution of colouring, 422 ; gradation
of secondary sexual characters in,
430; obscurely coloured, building
concealed nests, 454; young female,
acquiring male characters, 462;
breeding in immature plumage,
484; moulting of, 484; aquatic,

RIPGUS,

BLY IH,

627

frequency of white plumage in,
493; vocal courtship of, 567;
naked skin of the head and neck in,
801.

Birgus latro, habits of, 270.

Birkbeck, Mr., on the finding of new
mates by golden eagles, 408.

Birthplace of man, 155.

‘Births, numerical proportions of the
sexes in, in animals and man, 215,
216; male and female, numerical
proportion of, in England, 242.

Rischoff, Prof., on the agreement be-
tween the brains of man and of the
orang, 6; figure of the embryo of
the dog, 10; on the convolutions
of the brain in the human fetus,
11; on the difference between tke
skulls of man and the quadrumana,
149; resemblance between the ape’s
and man’s, 200.

Bishop, J., on the vocal organs of
frogs, 350; on the vocal organs of
corvine birds, 370; on the trachea
of the Meryanser, 374.

Bison, American, co-operation of, 101;
mane of the male, 521.

Bitterns, dwarf, coloration of the
sexes of, 461.

Biziura lobata, musky odour of the
male, 359; large size of male, 362.

Bl-ckbird, sexual differences in the,
219; proportion of the sexes in
the, 248 ; acquisition of a song by,
870; colour of the beak in the
sexes of the, 383, 491; pairing
with a thrush, 414; colours and
nidification of the, 455; young of
the, 487 ; sexual difference in colo-
ration of the, 491.

Black-buck, Indian, sexual difference
in the colour of the, 535.

Blackeap, arrival of the male, before
the female, 212; young of the,
487.

Black-cock, polygamous, 219; pro-
portion of the sexes in the, 248;
pugnacity and love-dance of the,
363; call of the, 375; moulting of
the, 392; duration of the court-
ship of the, 405; and pheasant,
hybrids of, 414; sexual difference
in coloration of the, 491; crimson

_ __ eye-cere of the, 491.

Blar cleck, Dr., on music, 572.

Bleck-grouse, characters of young,
465, 471.

Blackwall, J., on the speaking of tie
magpie, 90; on the desertion of
their young by swallows, i685 on
thesuperior activity of male spiders,
221; on the proportion of the
sexes in spiders, 254; on sexual
variation of colou: in spiders, 272 3
on male spiders, 272. .

Bladder-nose Seal, hood of the, 528,

Blaine, on the aifections of dogs,
523.

Blair, Dr., on the relative liability of
Europeans to yellow fever, 194,
Blake, C. C., on the jaw from La

Naulette, 40.

Blakiston, Capt., on the American
snipe, 377; on the dances of Zetrao
phasianellus, 381.

Blasius, Dr., on the species of Euro-
pean birds, 422.

Bledius taurus, hornlike processes of
male, 299,

Bleeding, tendency to profuse, 237.

Blenkiron, My., on sexual preference
in horses, 524,

Blennies, crest developed on the head
ot male, during the breeding sea-
son, 338.

Blethisa muiltipunctata, stridulation
of, 302.

Bloch, on the proportions of the sexes
in fishes, 249.

Blood, arterial, red colour of, 261.

pheasant, number of spurs in,

64.

Bluebreast, red-throated, sexual dif-
ferences of the, 472.

Blumenbach, on Man, 28; on the
large size of the nasal cavities in
American aborigines, 34; on the
position of man, 149; on the num-
ber of speciee of man, 174,

Blyth, E., on the structure of the
hand in the species of Hylobates,
51; observations on Judian crows,
102; on the development of the
horns in the Koodoo and Eland an-
telopes, 234; on the pugnacity of the
males of Gallinula cristata, 360; on
the presence of spurs in the female
Euplocamus er ytirophthalmus, 364 ;
on the pugnacity of the amadavat,
366; on the spoonbill, 374; on the

628

BOAR.

INDEX.

BOURWON

moulting of Anthus, 392; on the
moulting of bustards, plovers, and
Gallus bankiva, 892; on the Indian
honey-buzzard, 424; on sexual dif-
ferences in the colour of the eyes
of hornbills, 425; on Oriolus me-
lanocephalus, 460; on Paleornis
javanicus, 461; on the genus Ar-
detta, 461; on the peregrine falcon,
461; on young female birds acquir-
ing male characters, 461; on the
immature plumage of birds, 465;
on representative species of birds,
468; onthe young of Yurniz, 476;
on anomalous young of Lanius
rufus and Colymbus glacialis, 482 ;
on the sexes and young of the spar-
rows, 483; on dimorphism ):n some
herons, 484; on the ascertainment
of the sex of nestling bullfinches
by pulling out breast-feathers, 484 ;
on orioles breeding in immature
plumage, 484; on the sexes and
young of Buphus and Anastomus,
486; on the young of the black-
cap and blackbird, 487; on the
young of the stonechat, 487; on
the white plumage of Anastomus,
493; on the horns of Bovine ani-
mals, 505 ; on the horns of Antilo e
bezoartica, 507; on the mode of
fighting of Ovis cycloceros, 508;
on the voice of the Gibbons, 527 ;
on the crest of the male wild goat,
531; on the colours of Portax
picta, 535; on the colours of Anti-
lope bezoartica, 536 ; on the colour
of the Axis deer, 536; on sexual
difference of colour in Hylobates
hoolock, 537; on the hog-deer, 546;
on the beard and whiskers in a
monkey becoming white with age,
559.

Boar, wild, polygamous in India, 217 ;
use of the tusks by the, 513; fight-
ing of, 518.

Boardman, Mr., Albino birds in U.S.,
419,

Bsitard and Corbié, MM., on the
transmission of sexual peculiarities
in pigeons, 230; on the antipathy
shewn by some female pigeons to
certain males, 418.

Beld, Mr., on the singing of a sterile
hybrid canary, 369.

Bombet, on the variability of the
standard of beauty in Europe, 596.

Bombus, difference of the sexes in,
292.

Bombycida, coloration of, 313; pair-
ing of the, 318; colours ot, 318.
Bombycills carolmensis, ved append-

ages of, 461.

Bombyx cynthia, 278; proportion ot
the sexes in, 250, 253; pairing of,
318.

—— mori, difference of size of the
male and female cocoons of, 278;
pairing of, 318.

Pernyi, proportion of sexes of,

253.

Yamamai, 278; M. Personnat on,
251; proportion of sexes of, 253.
Bonaparte, C. L., on the call-notes of

the wild turkey, 375.

Bond, F., on the finding of new mates
by crows, 408.

Bore, implements of, skill displayed
in making, 49.

Boner, C., on the transfer of male
characters to an old female chamois,
504; on the habits of stags, 515 ;
on the pairing of red deer, 522.

Bones, increase of, in length and
thickness, when carrying a greater
weight, 32.

Bonizzi, P., difference of colour in

"sexes of pigeons, 230.

Bonnet monkey, 151.

Bonwick, J., extinction of Tasma
nians, 183, 184.

Boomerang, 145.

Boreus hyemalis, scarcity of the male,
254.

Bory St. Vincent, on the number of
species of man, 174; on the colours
ot Labrus pavo, 342,

Bos etruscus, 505.

gaurus, horns of, 505,

—— moschatus, 529.

primigenius, 501.

sondaicus, horns of, 505; coloura
of, 536. :

Botocudos, 144; rode of life of, 197;
disfigurement of the ears and lower
lip of the, 575.

Boucher de Perthes, J. C. de, on the
antiquity of man, 2.

Bourbon, proportion of the sexes in a
species of Papilio from, 250.

BOURIEN.

INDEX,

BROCA. 629

Bourien, cn the marriage-customs of
‘ne savages of the Malay Archi-
pelago, 598.

Bovide, dewlaps of, 531.

Bower-birds, 406; habits of the, 381;
ornamented playing-places of, v4,
413.

Bows, use of, 179.

Brachycephalic structure,
explanation of, 56.

Brachyura, 268.

Brachyurus calvus, scarlet face of,
550.

Bradley, Mr., abductor ossig metatarsi
quinti in man, 42.

Brain, of man, agreement of the, with
that of lower animals, 6; convolu-
tions of, in the human fetus, 11;
influence of development of mental
faculties upon the size of the, 54;
influence of the development of, on
the spinal column and skull, 55;
larger in some existing mammals
than in their tertiary prototypes,
81; relation of the development of
the, to the progress of language,
87; disease of the, affecting speech,
88; difference in the convolutions
of, in different races of men, 167;
supplement on, by Prof. Huxley,
199 ; development of the gyri and
sulci, 204.

Ibvakenridge, Dr., on the influence of
climate, 32. :

Brandt, A., on hairy men, 19.

Braubach, Prof., on the quasi-religious
feeling of a dog towards his master,
96; on the self-restraint of dogs,
108.

Brauer, F., on dimorphism in Neuro-
themis, 291,

Brazil, skulls found in caves of, 168 ;
population of, 173; compression of
the nose by the natives of, 583.

Break between man and the apes,
156.

Brean:, proportion of the sexes in the,
249.

possible

Breeding, age of; in birds, 484.

—— season, sexual characters making
their appearance in the, in birds,
390.

Brehm, on the effects of intoxicating
liquors on monkeys, 7; on the
recognition of women by male Cyno-

cephah, 8; on the diversity of the
mental faculties of monkeys, 27;
on the habits of baboons, 51: cn
revenge taken by monkeys, 69; on
manifestations of maternal affection
by monkeys and baboons, 70; en
the instinctive dread of monkeys
for serpents, 71; on the ase of
stones as missiles hy, baboons, 81 ;
on a baboon using a mat for shelter
from the sun, 82; on the signal-
cries of monkeys, 87; on sentinels
posted by monkeys, 101; on co-ope-
ration of animals, 101; on an eagle
attacking a young Cercopithecus,
101; oz baboons in confinement pro-
tecting one of their number from
punishment, 103; on the habits
of baboons when plundering, 104;
on polygamy in Cynocephaius and
Cebus, 217; on the numerical pro-
portion of the sexes in birds, 247 ; on
the love-dance of the black-cock,
363; on Palamedea cornuta, 366;
on the habits of the Black-grouse,
366; on sounds produced by birds
of paradise, 376 ; on assemblages of
grouse, 4053; on the finding of new
mates by birds, 409; on the fight-
ing of wild boars, 518; on the
habits of Cynocephalus hamadryas,
590.

Brent, Mr., on the courtship of fowls,
417.

Breslau, numerical prwportion of male
and female births in, 243.

Bridgman, Laura, 88.

Brimstone butterfly, 312; sexual dif-
ference of colour in the, 322.

British, ancient, tattooing jractised
by, 574,

Broca, Prof., on the occurrence of the
supra-condyloid foramen in the
human humerus, 22; anthropo-
morphous apes more bipedal than
quadrupedal, 53; on the capacity of
Parisian skulls at different periods.
55; comparison of modern and
medieval skulls, 55; on tails of
quadrupeds, 58 ; on the influence of
natural selection, 61; on hybridity
in man, 170; on human remains
from Les Eyzies, 181; on the cause
of the difference between Europeans
znd Hindoos, 192.

630

BRODIE,

INDEX.

BURCHELL.

Brodie, Sir B., on the origin of the
moral sense in man, 98.

Bronn, H. G., on the copulation of
insects of distinct species, 275.

Bronze period, inen of, in Europe,
128,

Brown, R., sentinels of seals generally
females, 100; on the battles of
seals, 500; on the narwhal, 502;
on the occasional absence of the
tusks in the female walrus, 502;
on the bladder-nose seal, 528; on
the colours of the sexes in Phoca
Grenlandica, 5353; on the appre.
ciation of music by seals, 569; on
plants used as love-philters, by
North American women, 577.

Brown, Dr. Crichton, injury to iafants
during parturition, 244.

Brown-Séquard, Dr., on the inhezi-
tance of the effects of operations by
guinea-pigs, 60, 603.

Bruce, on the use of the elephant’s
tusks, 507,

Brulerie, P. de la, on the habits of
Ateuchus cicatricosus, 300; on the
stridulation of Ateuchus, 306.

Briinnich, on the pied ravens of the
Feroe islands, 424,

Bryant, Dr., preference of tame pigeon
for wild mate, 418.

, Capt, on the courtship of
Callorhinus ursinus, 522,

Bubas bison, thoracic projection of,
298.

Bucephalus capensis, difference of the
sexes of, in colour, 351.

Buceros, nidification and incubation of,
454,

bicornis, sexual differences in the

colouring of the casque, beak, and

mouth in, 425,

corrugatus, sexual differences in
the beak of, 383.

Buchner, L., on the origin of man,
3; on the use of the human foot as
a prehensile organ, 52 ; on the mode
of progression of the apes, 52; on
want of self-consciousness, &c., in
savages, 83.

Bucholz., Dr., quarrels of chameleons,
357,

Buckland, F., on the numerical pro-
portion of the sexes in rats, 247;
on the proportion of the sexes in

the trout, 249; on Chimara mon
strosa, 338.

Buckland, W., on the complexity of
crinoids, 91.

Buckler, W., proportion of sexes of
Lepidoptera reared by, 253,

Buckinghamshire, numerical propor-
tion of maleand female births in, 242,

Bucorax abyssinicus, inflation of the
neck-wattle of the male during
courtship, 383.

Budytes Raii, 212.

Buffalo, Cape, 508, ;

, Indian, horns of the, 505.

——. Italian, mode of fighting of the,
508.

Buffon, on the number of species of
man, 174,

Bufo sikimmensis, 349,

Bugs, 281.

Buist, R., on the proportion of the
sexes in salmon, 249; on the pug-
nacity of the male salmon, 332.

Bulbul, pugnacity of the male, 360;
display of under tail-coverts by the
male, 402.

Bull, mode of fighting of the, 508;
curled frontal hair of the, 531.

Buller, Dr., on the Huia, 208; the
attachment of birds, 410.

Bullfinch, sexual differences in the,
219; piping, 369; female, singing
of the, 370; courtship of the, 401;
widowed, finding a new mate, 408;
attacking a reed-bunting, 412;
nestling, sex ascertained by pulling
out breast-feathers, 484,

Bulltinches distinguishing persons,
412; rivalry of female, 420.

Bulls, two young, attacking an old
one, 101; wild, battles of, 501.

Bull-trout, male, colouring of, during
the breeding season, 340.

Bunting, recd, head feathers of the
male, 402; attacked by a bullfinch,
412. :

Buatings, characters of young, 464.

Buphus coromandus, sexes and young
of, 486; change of colour in, 494.
495,

Burchell, Dr., on the zebra, 545; on
the extravagance of a bushwomap
in adorning herself, 577 ; celibacy
unknown among the savages of
South Africa, 594; on the mar

BURKE,

INDEX.

CANINE.

631

riage-customs of the Bushwomen,
598.

Burke, on the number of species of
man, 174,

Burmese, colour of the beard in, 358.

Burton, Capt., on negro ideas of
female beauty, 579; on a universal
ideal of beauty, 582.

Bushmen, 64.

Bushwoman, extravagant ornamenta-
tion of a, 577.

Bushwomen, hair of, 167, marriage-
customs of, 598,

Bustard, throat-pouch of tne male,
373 ; humming noise produced by a
male, 377 ; Indian, ear-tufts of, 384.

Bustards, occurrence of sexual dif-
ferences and of polygamy among
the, 219; Jove-gestures of the male,
380; double moult in, 390, 392.

Butler, A. G., on sexual differences in
the wings of Aricoris epitus, 277;
courtship of butterflies, 307; on
the colouring of the sexes in
species of Thecla, 310; on the re-
semblance of Jphias glaucippe to a
leaf, 313; on the rejection of cer-
tain moths and caterpillars by
lizards and frogs, 326.

Butterfly, noise produced by a, 307;
Emperor, 307, 308 ; meadow brown,
instability of the ocellated spots of,
428.

Butterflies, proportion of the sexes in,
250; forelegs atrophied in some
male, 277 ; sexual difference in the
neuration of the wings of, 277;
pugnacity of male, 307 ; protective
resemblances of the lower surface
of, 311; display of the wings by,
314; white, alighting upon bits of
paper, 317; attracted by a dead
specimen of the same species, 317 ;
courtship of, 317 ; male and female,
inhabiting different stations, 321.

Buxton, C, observations on macaws,
102; on an instance of benevolence
in a parrot, 411,

Buzzard, Indian honey-, variation in
the crest of, 424.

C.
Cabbage tutterflies, 312.

Cachalut, large head of the male, 502. |

Cadences, musical, perception of, by
animals, 569,

Caecum, 20; large, in the early pro-
genitors of man, 160.

Caivina mosciata, pugnacity of the
male, 362.

Californian Indians, decrease of, 258.

Callianassa, chele of, figured, 267.

Callidryas, colours of sexes, 318.

Callionymus lyra, characters of the
male, 335,

Callorhinus ursinus, relative size of
the sexes of, 5153; courtship of,
522.

Calotes maria, 358.

— nigrilabris, sexual difference in
the colour of, 357.

Cambridge, 0. Pickard, on the sexes
of spiders, 255; on the size of male
Nephila, 273.

Camel, canine teeth of male, 502,
514.

Campbell, J.. on the Indian elephant,
218; on the proportion of male
and female births in the harems of
Siam, 245,

Campylopterus hemileucurus, 248,

Canaries distinguishiug persons, 412

Canary, polygamy of the, 220; change
of plumage in, after moulting, 238;
female, selecting the best singing
male, 268; sterile hybrid, singing
of a, 369; female, singing of the,
370; selecting a greenfinch, 415;
and siskin, pairing of, 415.

Canestrini, G., on rudimentary cha-
racters and the origin of man, 3;
on rudimentary characters, 11; on
the movement of the ear in man,
14; on the variability of the ver-
miform appendage in man, 21; on
the abnormal division of the maiar
bone in man, 39; on abnormal con-
ditions of the human uterus, 39;
on the persistence of the frontal
suture in man, 39; on the propor-
tion of the sexes in silk-moths, 250,
251; secondary sexual characters
of spiders, 272.

Cancer pagurus, 266.

Cantield, Dr., on the horns of the
Antilocapra 234,

Canine teeth in man, 46; diminution
of, in man, 53; diminution of, in
horses, 53; dieappearance of, ip

632

CANINES,

INDEX.

CEBUB.

male ruminants, 53; large, in the
early progenitors of min, 180,

Canines, and horns, inverse develop-
ment of, 514,

Canoes, use of, 48, 180.

Cantharis, difference of colour in the
sexes of. a species of, 294.

Cantharus lineatus, 341.

Capercailzie, polygamous, 2193 pro-
portion of the sexes in the, 248;
pugnacity of the male, 363 ; pairing
of the, 367; autumn meetings of
the, 370; call of the, 375; dura-
tion of the courtship of, 405; beha-
viour of the female, 419; inconve-
niznce of black colour to the ferale,
444 ; sexual difference in the colora-
tion of the, 491; crimson eye-cere
of the male, 491,

Capitonide, colours and nidification of
the, 455.

Capra agagrus, 508; crest of the
male, 531; sexual difference in the
colour of, 536.

Capreolus Sibivicns subecawlatus, 542.

Caprice, couamon to man and animals,
93.

Caprimulgus, noise made by the males
of some species of, with their
wings, 376.

virginianus, pairing of, 366.

Carabidae, 302, :

Carbonnier, on the natural history of
the pike, 249 ; on the relative size
of the sexes in fishes, 335; court-
ship of Chinese Macropus, 341.

Curcineutes, sexual difference of
colour in, 457.

Carcinus menus, 268, 269.

Curdinalis virginianus, 225,

Carduelis elegans, sexual differences of
the beak in, 360.

Carnivora, marine, polygamous habits
of, 218; sexual differences in the
colours of, 534,

Carp, numerical proportion of the
sexes in the, 249.

Carr, R., on the peewit, 366.

Carrier pigeon, Jate development of
the wattle in the, 238.

Carrion beetles, stridulation of, 302.
Carus, Prof. V., on the development
of the horns in merino sheep, 235.
Cassowary, sexes and incubation of

the, 478.

Castina, mode of holding wings, 315.

Castoreum, 529.

Casuarius galeatus, 478.

Cat, convoluted body in the extremity
of the tail of a, 23; sick, sympathy
of a dog with a, 103.

Cataract in Cebus Azare, 7.

Catarrh, liability of Cebus Azara to, 7.

Catarrhine monkeys, 153.

Caterpillars, bright colours of, 325.

Cathartes aura, 416,

jota, love-gestures of the male,

0

Catlin, G., correlation of colour and
texture of hair in the Mandans,
197; on the development of the
beard among North American
Indians, 560; on the great length
of the hair in some North American
tribes, 580.

Caton, J. D., on the development of
the horns in Cervus virgini mus and
strongyloceros, 234 ; on the presence
of traces of horns in th2 female
wapiti, 504; on the fighting of
deer, 5105 on the crest of the male
wapiti, 531; on the colours of tne
Virginian deer, 535; on sexual dif-
ferences of colour in the wapiti,
536; on the spots of the Virginian
deer, 546.

Cats, dreaming, 74; tortoise-shell, 230,
232, 237; enticed by valerian, 530;
colours of, 543,

Cattle, rapid increase of, in South
America, 47; domestic, lighter in
winter in Siberia, 229; horns of, 234,
505 ; domestic, sexual differences of,
late developed, 238 ; numerical } ro-
portion of the sexes in, 246.

Caudal vertebre. number of, in ina-
caques and baboons, 58; basal, of
monkeys, imbedded in the body, 59.

Cavolini, observations on Serranus,
162,

Cebus, maternal affection in a, 70;
gradation of species of, 175,

—— Apella, 205,

Azara, liability of, to the same

diseases as man, 7; distinct sounds

produced by, 84; early maturity

of the female, 558,

capucinus, polygamous, 217;

sexual differences of colour in, 537

hair on the head of, 549,

CEBUB.

INDEX.

CHELONIA,

033

arr vellerosus, hair on the head of,

49,

Cecidomyidz, proportions of the sexes
in, 354,

Celibacy, unknown among the savages
of South Africa and South America,
594,

Centipedes, 274.

Cephalopoda, absence of secondary
sexual characters in, 263,

Cephalopterus ornatus, 373.

—_ penduliger, 374.

Cerambyx heros, stridulant organ of,
303.

Ceratodus, paddle of, 37.

Ceratophora aspera, nasal appendages
of, 355,

Stoddartii, nasal horn of, 355.

Cerceris, habits ot, 291.

Cercocebus @thiops, whiskers, &c., of,
550.

Cercopithecus, young, seized by an
eagle and rescued by the troop,
101; definition of species of, 175.

cephus, sexual difference of colour

in, 537, 552.

cynosurus and griseoviridis,

colour of the scrotum in, 537.

Diana, sexual differences of

colour in, 537, 552, 553.

griseo-viridis, 101.

—~ petaurista, whiskers, &c., of,
550.

Ceres, of birds, bright colours of, 491.

Ceriornis Temminckii, swelling of the
wattles of the male during court-
ship, 383.

Cervulus, weapons of, 514,

moschatus, rudimentary horns
of the female, 504.

Cervus alces, 234.

— campestris, odour of, 529.

canadensis, traces of horns in
the female, 504; attacking a man,
511; sexual difference in the colour
of, 536.

—— eluphus, battles of male, 501;
horns of, with numerous points,
510,

— Eldi, 234.

— mantchuricus, 546. ;

—— paludosus, colours of, 536.

— strongyloceros, 234.

—— viryinanis, 234; horns of, in
course of modification, 511.

Ceryle, male black-belted in some
species of, 457.

Cetacea, nakedness of, 56,

Ceylon, frequent absence of beard 10
the natives of, 560.

Chaffinch, proportion of the sexes in
the, 248; courtship of the, 401.
Chaffinches, 369; new mates found

by, 4u8.

Chalcophaps indicus, characters of
young, 465,

Chalcosoma atlas, sexual differences
of, 295.

Chameleo, sexual differences in the
genus, 356,

bifurcus, 356, 557.

—— Ovwenii, 357.

—— pumilus, 357.

Ciamepetes unicolor, modified wing-
feather in the male, 377.

Chameleons, 354. ,

Chamois, danger-signals of, 100;
transfer of male characters to an
old female, 504.

Champneys, Mr., acromio-basilar
muscle and quadrupedal gait, 42.
Chapuis, Dr., on the transmission of
sexual peculiarities in pigeons, 230;
on streaked Belgian pigeons, 238,

446,

Char, male, colouring of, during the
breeding season, 340.

Characters, male, developed in fe-
males, 227; secondary sexual,
transmitted through both sexes,
227; natural, artificial, exaggera-
tion of, by man, 582.

Charadriws hiaticula and p’uvialis,
sexes and young of, 485.

Chardin on the Persians, 586.

Charms, worn by women, 577.

Charruas, freedom of divorce among
the, 598.

Chasmorhynchus, difference of coloui
in the sexes of, 389; colours of, 492.

niveus, 389.

tricarunculatus, 389.

Chastity, early estimation of, 119.

Chatterers, sexual differences in, 219.

Cheever, Rev. H. T., census of the
Sandwich Islands, 257,

Cheiroptera, absence of secondary
sexual characters in, 218.

Chele of crustacea, 265, 271.

Chelonia, sexual ditterences in 380.

CHENALOPEX.

634

INDEX.

COCHAN-CHINA.

Chenalopex eyyptiacus, wing-kuobs of,
364,

Chera progne, 392, 419.

Chest, proportions of, in soldiers and
sailors, 325 large, of the Quechua
and Aymara Indians, 34.

Chevrotains, canine teeth of, 514.

Crtasognatius, stridulation of, 306.

=—- Grantii, mandibles of, 300.

Children, legitimate and illegitimate,
proportion of the sexes in, 243.

Chiloe lice of the natives of, 170;
population of, 173.

Chimera monstrosu, bony process on
the head of the male, 338.

Chimzroid fishes, prehensile organs of
male, 331.

Chimpanzee, 561; ears of the, 14;
representatives of the eyebrows in
the, 19; hands of the, 50; absence
of mastoid processes in the, 53;
platforms built by the, 66; crack-
ing nuts with a stone, 81; direc-
tion of the hair on the arms of the,
151; supposed evolution of the,
1773 polygamous and social habits
of the, 590.

China, North, idea of female beauty
in, 578.

——,, Southern, inhabitants of, 197

Chinese, use of flint tools by the, 145 ;
difficulty of distinguishing the
xaces of the, 167; colour of the
beard in, 558; general beardless-
ness of the, 560; opinions of the,
on the appearance of Europeans and
Cingalese, 578; compression of the
feet of, 583.

Chinsurdi, his opinion of beards, 576,
581.

Chlumydera maculata, 382.

Crloéon, pedunculated eyes of the
male of, 274,

Chlvephaya, coloration of the sexes in,
460.

Chlorocelus Tanana (figured), 285.

Whorda Dorsalis, 161.

Chough, red beak of the, 491.

Chromidz, frontal protuberance in
male, 340; sexual differences in
colour of, 345.

Chrysemys picta, long claws of the
male, 350.

Chrysocovcy~, characters of young of,
465

1

Chrysomelida, stridulation of, 302

Cicada pruinosa, 282.

septendecim, 282,

Cicada, songs of the, 2813 rudimem
tary sound-organs in females of, 288,

Cicatrix of a burn, causing modifica-
tion of the facial bones, 55.

Cichla, trontal protuberance of male
340.

Cimetiére du Sud, Paris, 22.

Cincloramphus cruralis, large size of
male, 362.

Cinclus aquati us, 455,

Cingalese, Chinese opinion of the ap
pearance of the, 578,

Cirripedes, complemental males of.
208.

Civilisation, effects of, upon natural
selection, 1335 influence of, in the
competition of nations, 183.

Clanging of geese, &c., 368.

Claparéde, E., on natural selection
applied to man, 49.

Clarke, on the marriage-customs of
the Kalmucks, 598.

Classitication, 148,

Claus, C., on the sexes of Saphirina,
271,

Cleft-palate, inherited, 35,

Climacteris erythrops, sexes of, 479.

Climate, 31; cool, favourable to hu-
man progress, 133; power uf sup-
porting extremes of, by man, 182;
want of connexion of, with colour,
192,

Cloaca, existence of a, in the early
progenitors of man, 161.

Cloacal passage existing in the hu-
man embryo, 9.

Clubs, used as weapons before disper-
sion of mankind, 180,

Clucking of fowls, 368,

Clythra 4-punctata, stridulation of,
302.

Coan, Mr., Sandwich-islanders, 187.

Cobbe, Miss, on morality in hypothe
tical bee-community, 99.

Cobra, ingenuity of a, 352.

Coccus, 147,

Coccyx, 22, 23; in the human em-
bryo, 9; convoluted body at the
extremity of the, 23; imbedded in
the body, 59.

Cochin-China, notions of beauty of
the iuhabitauts et, O78, 380.

cock.

INDEX.

CO8METORNIb,

635

Yock, blind. fed by its companions,
103; game, killing a kite, 363;
eomb and wattles of the, 403; pre-
ference shewn by the, for young
hens, 420; game, transparent zone
in the hackles of a, 430. .

Cock of the rock, 405.

Cockatoos, 491, 492, 493; nestling,
4115 black, immature plumage of,
467.

Celenterata, absence of secondary
sexual characters in, 260,

Coffee, fondness of monkeys for, 7.

Cold, supposed effects. of, 32; power
of supporting, by man, 182.

Coleoptera, 294; stridulation of, 284;

Colynbus glavialis, anomalous young
of, 482,

Comb, development of, in fowis, 239.

Combs and wattlesin male birds, 403.

Community, preservation of variations
useful to the, by natural selectio.,
62.

Composit, gradation of species among
the, 175.

Comte, C., on the expression of the
ideal of beauty by sculpture, 581.
Conditions of life, action of changed,

upon man, 30; influence of, on
plumage of birds, 472.
Condor, eyes and comb of the, 472.
Conjugations, origin of, OL.

stridulant organs of, di d, 303,
Colias edusa and hyale, 319.
Collingwood, C., on the pugnacity of

the butterflies of Borneo, 307; on

butterflies being attracted by a

dead specimen of the same species,

317,

Colobus, absence of the thumb, 51.

Colombia, flattened heads of savages
of, 575.

Colonists, success of the English as,
142,

Coloration, protective, in birds, 489.

Colour, supposed to be dependent on
light and heat, 32; correlation of,
with immunity from certain poisons
and parasites, 193; purpose of, in
lepidoptera, 316; relation of, to
sexual functions, in fishes, 343;
difference of, in the sexes of snakes,
851; sexual differences of, in
lizards, 3573 influence of, in the
pairing of birds of different species,
415; relation of, to nidification,
4538, 456; sexual differences of, in
mammiuals, 53, 540; recognition of,
by quadrupeds, 540; of children,
in different races of man, 557; of
the skin in man, 604.

Colours, admired alike by man and
animals, 93; bright, due to sexual
selection, 261; bright, among the
lower animals, 261, 262; bright,
protective to butterflies and moths,
313; bright, in male fishes, 335,
340; transmission of, in birds, 448.

Volquhoun, example of reasoning in
a retriever, 78.

Columb. pusserina, young of, 467.

, 114, 126; absence of, in
some criminals, 116.

Constitution, difference of, in different
races of men, 168,

Consumption, liability of Cebus Azare
to, 7; connexion between com-
plexion and, 194,

Convergence of characters, 177.

Cooing of pigeons and doves, 374.

Cook, Capt., on the nobles of the
Sandwich Islands, 586,

Cope, E. D., on the Dinosauria, 158.

Cophotis ceylanica, sexual differences
of, 354, 357.

Cupris, 295.

Lsidis,

296,

lunaris, stridulation of, 303.

Corals, bright colours of, 260.

Coral-snakes, 353.

Cordylus, sexual difference of colour
in a species of, 357.

Corfu, habits of the Chaffinch in, 248.

Cornelius, on the proportions of the
sexes in Lucanus Cervus, 253.

Corpora Wolffiana, 161; agreement
of, with the kidneys of fishes, 11.

Correlated variation, 43.

Correlation, influence of, in the pro-
duction of races, 197,

Corse, on the mode of fighting of the
elephant, 514.

Corvus corone, 408.

graculus, red beak of, 491.

—— pica, nuptial assembly of,
406.

Corydalis cornutus, large jaws of the
male, 275.

Cosine ornis, 462.

sexual differences of,

536

COSMETORNIS,

INDEX.

CYANECULA.

eae A {
Cosmetornjs vexillarius, elongation of

wing-feathers in, 384, 403.

Cotingide, sexual differences in, 219;
coloration of the sexes of, 460; re-
semblance of the females of distinct
species of, 470.

Cottus scorpius, sexual differences in,
337,

Coulter, Dr., on the Californian In-
dians, 258.
Counting, origin of, 144; limited
power of, in primeval man, 180.
Courage, variability of, in the same
species, 69; universal high appre-
cjation of, 118; importance of,
130; characteristic of men, 564,

Courtship, greater eagerness of males
in, 2215 of fishes, 331, 341; of
birds, 367, 405.

Cow, winter change of colour, 542.

Crab, devil, 269.

, Shore, habits of, 268.

Crabro cribrarius, dilated tibie of the
male, 276,

Crabs, proportions of the sexes in,
255,

Cranz, on the inheritance of dexterity
in seal catching, 33.

Crawfurd, on the number of species
of man, 174.

Crenilabrus massa and C. melops, nests
built by, 345,

Crest, origin of, in Polish fowls, 231.

Crests, of birds, difference of, in the
sexes, 467; dorsal hairy, of mam-
mals, 530.

Cricket, field-, stridulation of the,
283; pugnacity of male, 289.

—-, house-, stridulation of the
283, 284.

Crickets, sexual differences in, 289.

Crioceride, stridulation of the, 302.

Crinoids, complexity of, 91.

Croaking of frogs, 350.

Crocodiles, musky odour of, during
the breeding season, 351.

Crocodilia, 351.

Crossbills, characters of young, 464.

Crosses in man, 173.

Crossing of races, effects of the, 192.

Crossoptilon auritum, 400, 452, 472;
adornment of both sexes of, 235 ;
sexes alike in, 460.

crotch, G. R., on the stridulation of
beetles, 302, 304; on .he stridu-

lation of Heliopathes, 305; on the
stridulation of Acalles, 306; habit
of female deer at breeding time, 503,

Crow Indians, long hair of the, 580.

, young of the, 481.

Crows, 4913 vocal organs of the, 370:
living in triplets, 409.

—, carrion, new mates found by,
407.

, Indian, feeding their blind com-
panions, 103,

Cruelty of savages to animals, 118.

Crustacea, parasitic, loss of limbs by
female, 208; prehensile feet and
antenne of, 209; male, more active
than female, 221; parthenogenesis
in, 255; secondary sexual charac-
ters of, 265; amphipod, males
sexually mature while young, 485;
auditory hairs of, 568.

Crystal worn in the lower lip by some
Central African women, 575.

Cuckoo fowls, 238.

Culicide, 208, 280; attracted by each
other’s humming, 280.

Cullen, Dr., on the throat-pouch of
the male bustard, 373.

Cultivation of plants, probable origin
of, 133.

Cupples, Mr., on the numerical pro-
portion of the sexes in dogs, sheep,
and cattle, 246; on the Scotch
deerhound, 516; on sexual pre-
ference in dogs, 524.

Curculionide, sexual difference in
length of snout in some, 208;
hornlike processes in male, 299;
musical, 301, 302.

Curiosity, manifestations of, by ani-
mals, 71.

Curlews, double moult in, 390.

Cursores, comparative absence of
sexual differences among the, 219.

Curtis, J., on the proportion of the
sexes in Athalia, 254.

Cuvier, F., on the recognition of
women by male quadrumana, 8.

» G., on the number of caudal
vertebre in the mandrill, 58; on
instinct and intelligence, 67 ; views
of, as to the position of man, 149;
on the position of the seals, 150;
on Hectocoty/le, 263.

Cyanecula suecica, sexual differs 98
of, 472,

CYANALCYON.

INDEX.

DENDROPHILA.

037

Oyanaicyon, sexual difference in
colours of, 457; immature plu-
mage of, 467.

' Cychrus, sounds produced by, 304.

Cycnia mendica, sexual difference of,
in colour, 316.

Cygnus ferus, trachea of, 374.

olor, white young of, 482.

Cyllo Leda, instability of the ocellated
spots of, 428.

Cynanthus, variation in the genus,
423,

Cynipide, proportions of the sexes in,
254,

Cynocephalus, difference of the young
from the adult, 8; male, recogni-
tion of women by, 8; polygamous
habits of species of, 217.

chacma. 70.

gelada, 81.

hamadryas, 81, 590; sexual dif-

ference of colour in, 537.

leucophus, colours of the sexes

of, 538.

mormon, colours of the male,

538, 540, 550,

porcarius, mane of the male,
521.

Cypridina, proportions of the sexes in,
255.

Cyprinide, proportion of the sexes in
the, 249.

» Indian, 343, :

Cyprinodontide, sexual differences in
the, 335, 337.

Cyprinus auratus, 342.

Cypris, relations of the sexes in, 255.

Cyrtodactylus rubidus, 354.

Cystophora-cristuta, hood of, 528,

D.

Dacelo, sexual difference of colour in,
457.

Gaudictaudi, young male of,
467.

Dal-ripa, a kind of ptarmigan, 248.

Damalis albifrons, peculiar markings
of, 544,

— pygarga, peculiar markings of,

Dampness of climate, supposed influ-
ence of, on the ccluur of the skin,
32, 193.

Danaide, 308.

i

Dances of birds, 380.

Dancing, universality of, 178.

Daniell, Dr., his experience of resi-
dence in West Africa, 195,

Darfur, protuberances artificially pro-
duced by natives of, 574.

Darwin, F., on the stridulation of
Dermestes murinus, 302.

Dasychira pudibunda, sexual difference
of colour in, 316.

Davis, A. H., on the pugnacity of the
male stag-bectle, 300.

» J. B., on the capacity of the
skull in various races of men, 5+;
on the beards of the Polynesians,
560.

Death-rate higher in towns than in
rural districts, 139.

Death-tick, 306.

De Candolle, Alph., on a case of in-
herited power of moving the scalp,
13.

Declensions, origin of, 91.

Decoration in birds,.381.

Decticus, 285.

Deer, 233 ; development of the horns
in, 233; spots of young, 464, 546;
horns of, 503, 506; use of horns
of, 510, 518; horns of a, in course
of modification, 511; size of the
horns of, 515; female, pairing with
one male, whilst others are fighting
for her, 522; male, attracted by
the voice of the female, 527; male,
odour emitted by, 529,

, Axis, sexual difference in the

colour of the, 537.

» fallow, different coloured herds

of, 540.

, Mantchurian, 546.

» Virginian, 546; colour of the,
not affected by castration, 535;
colours of, 536.

Deerhound, Scotch, greater size of the
male, 237, 516.

Defensive organs of mammals, 518,

De Geer, C., on a female spider de
stroying a male, 273.

Dekay, Dr., on the bladder-nose seal,
528.

Delorenzi, G., division of malar bong
39, 5

Demerara, yellow fever in, 194.

Dendrocygna, 464,

Dendrophila frontalis, young of, 487

638

DINISON.

INDEX,

BOGS.

Denison, Sir W., manner of riddivg
themselves of vermin among the
Australians, 57; extinction of Tas-
manians, 184,

Denny, H., on the lice of domestic
animals, 169.

Dermestes murinus, stridulation of,
302,

Descent traced through the mother
alone, 588.

Deserts, protective colouring of ani-
mals inhabiting, 489.

Desmarest, on the absence of sub-
orbital pits in Antilope subguttu-
rosa, 529; on the whiskers of
Macacus, 5313; on the colour of
the opossum, 534; on the colours
of the sexes of Mus minutus, 534;
on the colouring of the ocelot, 534;
on the colours of seals, 535; on
Antilope caama, 536; on the
colours of goats, 536; on sexual
difference of colour in Atvles mar-
ginatus, 537; on the mandrill,
539; on Macacus cynomolgus, 558,

Desmoulins, on the number of species
of man, 174; on the musk-deer,

530. '

Desor, on the imitation of man by
monkeys, 72.

Despine, P., on criminals destitute of
conscience, 116.

Development, embryonic, of man, 9,
11; correlated, 426.

Devil, not believed in by the Fue-
gians, 95.

Devil-crab, 269.

Devonian, fossil insect from the, 289.

Dewlaps, of cattle and antelopes, 531.

Diadema, sexual differences of colour-
ing in the species ot, 309.

Diamond-beetles, bright colours of,
294,

Diastema, occurrence of, in man, 35.

Diastylide, proportion of the sexes in,

55.

Dicrurus, racket-shaped feathers in,
384; nidification of, 453.

—— macrocercus, change of plumage
in, 461.

Didelphis opossum, sexual difference
in the colour of, 533.

Differences, comparative, bet ween dif-
ferent species of birds of the same
sex, 170.

Digits, supernumerary, more frequent
in men than in women, 223; super-
numerary, inheritance of, 232;
supernumerary, early devel pment
of, 237.

Dimorphism in females of water-
beetles, 276; in Neurothemis and
Agrion, 291.

Diodorus, on the absence of beard it
the natives of Ceylon, 560.

Dipeticus Cantori, sexual differences
of, 296,

Diplopoda, prehensile limbs of the
male, 274.

Dipsas cynodon, sexual difference in
the colour of, 351.

Diptera, 280.

Disease, generated by the contact of
distinct peoples, 183.

Diseases common to man and the
lower animals, 7; difference of
liability to, in different races of
men, 167; new, effects of, upon
savages, 182; sexually limited,
237,

Display, coloration of Lepidoptera
for, 314; of plumage by male
birds, 394, 402.

Distribution, wide, of man, 48; geo-
graphical, as evidence of specitic
distinctness in man, 169.

Disuse, effects of, in producing rudi-
mentary organs, 12; and use of
parts, effects of, 32; of parts, in-
tuence of, on the races of men, 197,

Divorce, freedom of, among the Char-
ruas, 598,

Dixon, E. S., on the patring of different
species of geese, 415; on the court-
ship of peafowl, 419.

Dobrizhoffer, on the marriage-custome
of the Abipones, 599.

Dobson, Dr., on the Cheiroptera, 218;
scent-glands of bats, 529; fru
givorous bats, 534.

Dogs, suffering from Tertian ague, 8;
memory of, 74; dreaming, 743
diverging when drawing sledges
over thin ice, 75; exercise of reason-
ing faculties by, 78; domestic, pro-
gress of, in moral qualities, 80;
distinct tones uttered by, 84;
parallelism between his affection for
his master and religious feeling, 96:
sociability of the, LUV; sympathy of.

DOLICHOCEPHALIC.

INDEX.

EAGLE,

639

with a sick cat, 103; sympathy of,
with his master, 103; their posses-
sion of conscience, 1033; possible use
of the hair on the fore-legs of the,
1515 races of the, 176; numerical
proportion of male and female births
in, 246; sexual affection between in-
dividuals of, 524; howling at certain
Notes, 569; rolling in carrion, 530.

Dolichocephalic structure, possible
cause of, 56,

Dolphins, nakedness of, 56.

Domestic animals, races of, 176;
change of breeds of, 596.

Domestication, influence of, in re-
moving the sterility of hybrids, 172

D’Orbigny, A., on the influence of
dampness and dryness on the colour
of the skin, 193; on the Yuracaras,
582.

Dotterel, 477.

Doubleday, E., on sexual differences
in the wings of butterflies, 277.

» H. on the proportion of the
sexes in the smaller moths, 251;
males of Lasiocampa quercus and
on the attraction of the Sa-
turnia carpint by the female 252;
on the proportion of the sexes in
the Lepidoptera, 252; on the tick-
ing of <dAnobium tesselatum, 306 ;
on the structure of Ageronia
feronia, 307; on white butterflies
alighting upon paper, 317.

Douglas, J. W., on the sexual differ-
ences of the Hemiptera, 281; onthe
colours of British Homoptera, 282.

Down, of birds, 390.

Draco, gular appendages of, 355,

Dragonet, Gemmeors, 336,

Dragon-flies, caudal appendages of
male, 276; relative size of the
sexes of, 279; difference in the
sexes of, 290; want of pugnacity
by the male, 291.

Drake, breeding plumage of the, 393.

Dreams, 74; a possible source of the
belief in spiritual agencies, 94.

Drill, sexual difference of colour in
the, 538.

Drumeus, irroratus, 478.

‘rvmolea, Saharan species of, 456.

Drongo shrike, 461,

Drougos, racket-shaped feathers in
the tails ut, 384, 392.

Dryness, of climate, supposed influence
of, on the colour of the skin, 193.

Dryopithecus, 155.

Duck, harlequin, age of mature plu-
mage in the, 483; breeding in im-
mature plumage 484.

, long-tailed, preterence of male,

for certain females, 420.

, pintail, pairing with a wigeon,

4,

—, voice of the, 374; pairing with
a shield-drake, 414; immature
plumage of the, 466.

, wild, sexual differences in the
219; speculum and male charac-
ters of, 236; pairing with a pintail
drake, 415,

Ducks, wild, becoming polygamous
under partial domestication, 219
dogs and cats recognised by, 412.

Dufossé, Dr., sounds produced by fish,
347.

Dugong, nakedness of, 56; tusks of,
502,

Dujardin, on the relative size of the
cerebral ganglia in insects, 54,

Duncan, Dr., on the fertility of early
marriages, 138 ; comparative health
of married and single, 140.

Dupont, M., on the occurrence of’ the
supra-condyloid foramen in the
humerus of man, 22.

Durand, J. P., on causes of variation,
30.

Dureau de la Malle, on the songs of
birds, 86; on the acquisition of an
air by blackbirds, 370.

Dutch, retention of their colour by
the, in South Africa, 193.

Duty,’sense of, 97.

Duvaucel, temale //ylubates washing
her young, 70.

Dyaks, pride of, in mere homicide, 117.

Dynastes, large size of males of, 279.

Dynastini, stridulation of, 303.

Dytiscus, dimorphism of females of,
276; grooved elytra of the female,
276.

E

Eagle, young Cercopithecus rescued
trom, by the troop, 101.

, White-headed, breeding in im

mature plumage, 434,

640

EAGLES.

INDEX.

ENJLEWEART.

Eagles, golden, new mates found by,
408,

Ear, motion of the, 13; external
shell of the, useless in man, 14;
rudimentary point of the, in man, 15.

Ears, more variable in men than
women, 224; piercing and orna-
mentation of the, 575.

Earwigs, parental feeling in, 106.

Echidna, 156.

Echini, bright colours of some, 260.

Echinodermata, absence of secondary
sexual characters in, 260.

Echis ¢ winuta, 353.

Ecker, figure of the human embryo,
10; on the development of the
gyri and sulci of the brain, 204;
on the sexual differences in the
pelvis in man, 557; on the pre-
sence of a sagittal crest in Austra-
lians, 558.

Edentata, former wide range of, in
America, 169 ; absence of secondary
sexual characters in, 218.

Edolius, racket-shaped feathers in,
384,

Edwards. Mr., on the proportion of
the sexes in North American species
of Papilio, 250.

Eels, hermaphroditism of, 162.

Egerton, Sir P., on the use of the
antlers of deer, 510; on the pairing
of red deer, 522; on the bellowing
of stags, 526.

Eggs, hatched by male fishes, 345,

Egret, Indian, sexes and young of, 486.

Egrets, breeding plumage of, 391;
white, 492.

Ehrenberg, on the mane of the male
Hamadryas baboon, 521.

Ekstrém, M., on Harelda glacialis,
420,

Elachista rufocinerea, habits of male,
252,

Eland, development of the horns of
the, 234,

Eiands, sexual differences of colour in
585

Elaphomyia, sexual differences in, 280.

Hlaphrus uliginosus, stridulation of,
302.

Elaps, 353.

Elateride, proportions of the sexes in,
253.

Klaters, luminous, 278.

Elephant, 156; rate of increase of
the, 47; nakedness of the, 57; in-
dian, forbearance to his keeper,
104; polygamous habits of the,
218; pugnacity of the male, 501;
tusks of, 502%, 503, 507, 5153
Indian, mode of fighting of the,
513; male, odour emitted by the,
529; attacking white or grey
horses, 540.

Elevation of abode, modifying in-
fluence of, 35.

Elimination of inferior individuals,
137.

Elk, 507; winter change of the, 542.

»irish, horns of the, 515,

Ellice Islands, beards of the natives,
560, 581.

Elliot, R., on the numerical pro-
portion of the sexes in young rats,
247; on the proportion of the
sexes in sheep, 246.

, D. G., on Pelecanus erythro-

rhynchus, 390,

, Sir W., on the polygamous
habits of the Indian wild boar,
218.

Ellis, on the prevalence of infanticide
in Polynesia, 592.

Elphinstone, Mr., on local differences
of stature among the Hindoos, 31,
on the difficulty of distinguishing
the native races of India, 167.

Elytra, of the females of Dytiscus,
Acilius, Hydroporus, 276.

Emberiza, characters of young, 464.

— miliaria, 464,

scheniclus, 412;
of the male, 402.

Embryo of man, 9, 10; of the dog, 10.

Embryos of mammals, resemblance of
the, 25.

Emigration, 137,

Emotions experienced by the lower
animals in common with man, 69;
manifested by animals, 71.

Emperor moth, 315.

Emulation of singing-birds, 369.

Emu, sexes and incubation of, 478.

Endurance, estimation of, 118,

Energy, a characteristic of men 565,

England, numerical propertion of
male and female births in, 242.

Engleheart, Mr., on the finding of
new mates by starliags, 498.

head-feathers

ENGLISII.

INDEX.

FACULTIES.

641

English, success of, as colonists, 142.
Engravers, short-sighted, 33.
Entomostraca, 268,

Entozoa, difference of colour between

« the males and females of some, 260.

Envy, persistence of, 112,

Eocene period, possible divergence of
man during the, 156.

Solid, colours of, produced by the
biliary glands, 261.

Epeira nigra, small size of the male
of, 273

Ephemera, 274.

Ephemeride, 290.

Ephippiger vitium, stridulating orgaus
of, 284, 288,

Epicalia, sexual differences of colour-
ing in the species of, 309.

Equus hemionus, winter change of,
542,

Erateina, coloration of, 315.

Ercolani, Prof., hermaphroditism in
eels, 162,

Erect attitude of man, 51, 52.

Eristalis, courting of, 280.

Eschricht, on the development. of hair
in man, 18; on a lanuginous
moustache in a female fetus, 19;
on the want of detinition between
the scalp and the forehead in some
children, 151; on the arrangement
of the hair in the human fetus, 152;
on the hairiness of the face in the
human fetus of both sexes, 602, 603.

Esmeralda, ditference of colour in the
sexes of, 294.

Esox lucius, 249.

reticulatus, 340,

Esquimaux, 64, 133; their belief in
the inheritance of dexterity in
seal-catching, 33; mode of lite of
197.

Estrelda amandava, pugnacity of the
male, p66.

Eubagis, sexual differences of colour-
ing in the species of, 309.

Euchirus longimanus, sound produced
by, 304.

Eudromias morinellus, 477.

Eulumpis jugwlaris, colours of the
female, 454,

Euler, on the rate of increase in the
United States, 44.

Eumomota superciliaris, racket-shaped
feathers in the tail of, 384.

42

Eupetomena macroura, colours of the
female, 453.

Euphema splendida, 457.

Euplocamus erythrophtialmus, posses-
sion of spurs by the female, 364.

Europe, ancient inhabitants of, 181.

Europeans, difference of, from Hin-
doos, 1925; hairiness of, probably
due to reversion, 601.

Eurostopodus, sexes of, 479.

Eurygnathus, different proportions of
the head in the sexes of, 276.

Eustephanus, sexual differences of spe-
cies of, 359; young of, 487.

Exaggeration of natural characters by
man, 582.

Exogamy, 588, 591.

Expression, resemblances in, between
man and the apes, 150.

Extinction of races, causes of, 181.

Eye, destruction of the, 32; change
of position in, 55; obliquity of,
regarded as a beauty by the Chinese
and Japanese, 578.

Eyebrows, elevation of, 13; develop-
ment of long hairs in, 19; in mon-
keys, 1513 eradicated in parts of
South America and Africa, 575;
eradication of, by the Indians of
Paraguay, 580.

Eyelashes, eradication of, by the In-
dians of Paraguay, 580.

Eyelids, coloured black, in part of
Africa, 574.

Eyes, pillared, of the male of Chloéon,
274; difference in the colour of,
in the sexes of birds, 425,

Eyton, T. C., observations on the de-
velopment of the horns in the
fallow-deer, 234,

Eyzies, Les, human remains from,
181,

F.

Fabre, M., on the habits of Cerceris,
2a1,

Facial bones, causes of modification
of the, 5),

Faculties, diversity of, in the same
race of men, 26; inheritance of, 27;
diversity of, in animals of the same
species, 28; mental, variation ot,
in the same species, 66; of birds
410.

642

FAKIRS,

INDEX.

FISH.

Fakirs, Indian, tortures andergone sy,
118

Falco leucocephalus, 484.

peregrinus, 408, 451.

tinnunculus, 408,

Falcon, peregrine, new mate found
by, 408.

Falconer, H., on the mode of fighting
of the Indian elephant, 513; on
canines in a female deer, 514; on
Hyomoschus aquaticus, 547.

Falkland Islands, horses of, 181.

Fallow-deer, different coloured herds
of, 540,

Famines, frequency of, among savages,

Farr, Dr., on the structure of the
uterus, 38; on the effects of pro-
fligacy, 137; on the influence of
marriage on mortality, 139, 140.

Farrar, F, W., on the origin of lan-
guage, 87 ; on the crossing or blend-
ing of languages, 91; on the
absence of the idea of God in cer-
tain races of men, 93; on early
marriages of the poor, 138; on the
middle ages, 141.

Fashions, long prevalence of, among
savages, 576, 584.

Faye, Prof., on the numerical propor-
tion of male and female births in
Norway and Russia, 243; on the
greater mortality of male children
at and betore birth, 243.

Feathers, modified, producing sounds,
377 et seq.. 450; elongated, in
male birds, 383, 403; racket-
shaped, 384; barbless and with
filamentous barbs in certain birds,
385 ; shedding of margins of, 393.

Feeding, high, probable influence of,
in the pairing of birds of different
species, 415,

Feet, thickening of the skin on the
soles of the, 33; modification of,
in man, 52.

Felis canadensis, throat-ruff of, 521.

pardalis and F. mitis, sexual
differences in the colouring of, 534,

Female, behaviour of the, during
courtship, 222.

birds, differences of, 470.

Females, presence of rudimentary
male organs in, 102; preference
of, for certain males, 214; pursuit

of, by males, 221; occurrence of
secondary seyual characters in,
225; development of male charac
ters by, 227.

Females and males, comparative nume
bers of, 213, 215; comparative mur-
tality of, while young, 216.

Femur and tibia, proportivns of, in the
Aymara Indians, 34.

Fenton, Mr., decrease of Maories,
184; infanticide amongst the
Maories, 256.

Ferguson, Mr., on the courtship ot
fowls, 417.

Fertility lessened under changed con-
ditions, 188.

Fertilisation, phenomena of, in plants,
222; in the lower animals, 222.
Fevers, immunity of Negroes and

Malattoes from, 193.

Fiber zib thicus, protective colouring
of it, 542.

Fick, H., effect of conscription for
military service, 134.

Fidelity of savages to one another,
118; importance of, 124.

Field-slaves, ditference of, from house-
slaves, 196.

Fijians, burying their old and sick

. parents alive, 1025; estimation of
the beard among the, 581; admi-
ration of, for a broad occiput,
583,

Fiji Archipelago, population of the,
173.

Islands, beards of the natives.
560, 581; mariiage-customs of the,
598,

Filial affection, partly the result of
natural selection, 105.

Filum terminale, 23.

Finch, racket-shaped feathers in the
tail of a, 384,

Finches, spring change of colour in,
393; British, females of the, 460.

Fingers, partially coherent, in species
of Hylobates, 51.

Finlayson, on the Cochin Chinese,
578.

Fire, use of, 49, 145, 180.

Fischer, on the pugnacity of the male
of Lethrus cephulotes, 300.

Fish, eagerness of male, 2213 proper-
tion of the sexes in, 2493; sounds
produced by, 347.

FISIIES.

INDEX.

FRINGILLID.

043

fohes, kidneys of, represented by
Corpora Wolffiana in the human
embryo, 11; male, hatching ova
in their mouths, 163; receptacles
for ova possessed by, 208; relative
size of the sexes in, 3353 fresh-
water, of the tropics, 343; protec-
tive resemblances in, 344; change
of colour in, 344; nest-building,
345; spawning of, 345; sounds
produced by, 347, 566; continued
growth of, 485.

Flamingo, age of mature plumage,
483.

Llexor pollicis longus, similar variation
of, in man, 42.

Flint tools, 145.

Flints, difficulty of chipping into
form, 49.

Floresuga mellivora, 443,

Florida, Quiscalus major in, 248.

Flounder, coloration of the, 344

Flower, W. H., on the abductor of
the fifth metatarsai in apes, 42;
on the position of the Seals, 150;
on the Pithecia monachus, 201;
on the throat-pouch of the male
bustard, 373.

Fly-catchers, colours and nidification
of, 455,

Fetus, human, woolly covering of
the, 19; arrangement of the hair
on, 152.

Food, influence of, upon stature, 31.

Fuot, prehensile power of the, re-
tained in some savages, 52; pre-
hensile. in the early progenitors of
man, 160.

Foramen, supra-condyloid, excep-
tional occurrence of in the humerus
of man, 21, 43; in the early pro-
genitors of man, 160.

Forbes, D., on the Aymara Indians,
34; on local variation of colour
in the Quichuas, 196; on the hair-
lessness of the Aymaras and Qui-
chuas, 561; on the long hair of
the Aymaras and Quichuas, 559,
580. :

Forel, F., on white young swans,
292.

Formica rufa, size of the cerebral
ganglia in, 54.

Fossils, absence of, connecting man
with the apes, 156.

Fowl, occurrence of spurs in the
female, 227 ; game, early pugnacity
otf, 239; Polish, early development
of cranial peculiarities of, 239;
variations in plumage of, 385; ex-
amples of correlated development
in the, 426; domestic, breeds and
subkreeds of, 460. :

Fowls, spangled Hamburgh, 229, 238 ;

- inheritance of changes of plumage
by, 229; sexual peculiarities in,
transmitted only to the same sex,
230; loss of secondary sexual cha-
racters by male, 231; Polish, origin
of the crest in, 2315 period of in-
heritance of characters by, 238;
cuckoo-, 238; development of the
comb in, 2395 numerical propor-
tion of the sexes in, 247 ; courtship
of, 417; mongrel, between a black
Spanish cock and different hens,
427; pencilled Hamburgh, differ-
ence of the sexes in, 447 ; Spanish,
sexual differences of the comb in,
447; spurred, in both sexes, 449.

Fox, W. D., on some halt-tamed wild
ducks becoming polygamous, and
on polygamy in the guinea-fowl and
canary-bird, 220; on the proportion’
of the sexes in vattle, 247; on the
pugnacity of the peacock, 364; on
a nuptial assembly of magpies,
406; on the finding of new mates
by crows, 407 ; on partridges living
in triplets, 409; on the pairing of a
goose with a Chinese gander, 415.

Foxes, wariness of young, in hun!ing
districts, 80; black, 540.

Fraser, C., on the different colours of
the sexes in a species of Sguilla,
271.

, G., colours of Thecla, 312.

Frere, Hookham, quoting Theognis on
selection in mankind, 29.

Fringilla oannahina, 394.

ciris, age of mature plumage iu

483,

cycnea, age of mature plumage

in, 483."

leucophrys, young of, 486.

spinus, 415,

tristis, change of colour in, iv
spring, 393; young of, 485,

Fringillida, rssemblance of the fe
males of distinct species of. 470

FROGS.

544

INDEX.

GELASIMUS.

Frogs, 349; male, temporary recep-
tacles for ova possessed by, 208;
ready to breed before the females,
212; fighting of, }49; vocal organs
of, 350,

Frontal bone, persistence of the suture
in, 39.

Fruits, poisonous, avoided by animals,
66.

Fuegians, 133, 143; difference of sta-
ture among the, 31; power of sight
in the, 33; skill of, in stone-throw-
ing, 49; resistance of the, to their
severe climate, 63, 182; mental
capacity of the, 65 ; quasi-religious
sentiments of the, 95; resemblance
of, in mental characters, to Euro-
peans, 178; mode of life of the,
197; aversion of, to hair on the
face, 580; said to admire European
women, 582.

Fulgoride, songs of the, 281.

Fur, whiteness of, in arctic animals,
in winter, 229,

Fur-bearing animals, acquired saga-
city of, 80.

G

Gallicrexz, sexual difference in the
colour of the irides in, 425.

— cristatus, pugnacity of male,
360; red caruncle occurring in
the male during the breeding-
season, 389.

Gallinacee, frequency of polygamous
habits and of sexual differences in
the, 219; love-gestures of, 380;
decomposed feathers in, 385 ; stripes
of young, 464; comparative sexual
differences between the species of,
470, 471; plumage of, 472.

Gallinaceous birds, weapons of the
male, 362; racket-shaped feathers
on the heads of, 384.

Gallinula chloropus, pugnacity of the
male, 360.

cristata, pugnacity of the male,
360.

Galloperdix, spurs of, 364; develop-
ment of spurs in the female, 450.

Gallophasis, young of, 468.

Gallus banhiva, 447 ; neck-hackles of,
392.

— S‘anleyi, pugnacity of the male,

363.

Galls, 60.

Galton, Mr., on hereditary genius, 28 ;
gregariousness and independence
in animale, 104; on the struggle
between the social and personal!
impulses, 125; on the effects of
natural selection on civilised na-
tions, 133; on the sterility of sole
daughters, 135; on the degree of
fertility of people of genius, 136;
on the early marriages of the poor,
138; on the ancient Greeks, 140;
on the Middle Ages, 141; on the
progress of the United States, 142;
on South African notions of beauty,
579,

Gammarus, use of the chelz of, 268.

marinus, 270.

Gannets, white only when mature,
492,

Ganoid fishes, 159, 165.

Gaour, horns of the, 505.

Gap between man and the apes, 156.

Gaper, sexes and young of, 486.

Gardner, on an example of rationality
in a Gelasimus, 270.

Garrulus glandarius, 407.

Gartner, on sterility of hybrid plants,
172,

Gasteropoda, 272;
courtship of, 262.

Gasterosteus, 220;
345.

leturus, 331, 340, 345.

trachurus, 352.

Gastrophora, wings of, brightly co-
loured beneath, 315.

Gauchos, want of humanity among
the, 123.

Gaudry, M., on a fossil monkey, 154.

Gavia, seasonal change of plumage in,
493.

Geese, clanging noise made by, 368
pairing of different species of, 415;
Canada, selection of mates by, 415.

Gegenbaur, C., on the number of
digits in the Ichthyopterygia, 37 ;
on the hermaphroditism of the
remote progenitors of the verte-
brata, 161; two types of nipple in
mammals, 162.

Gelasimus, proportions of the sexes
in a species of, 254; use of the
enlarged chelex of the male, 268;
pugnacity of males of, 269; rational

pulmoniferous,

nidification of,

GEMMULES.

INDEX.

GONEPTERYX,.

645

actions of a, 270, difference of
colour in the sexes of a species of,
271.

Gemmules, dormant in one sex, 231.

Genius, 28 ; hereditary, 564.

——-, fertility of men and women of,
136.

Geoffroy-Saint-Hilaire, Isid., on the
recognition of women by male
quadrumana, 8; on monstrosities,
30; coincidences of arrested devel-
opment with polydactylism, 37;
on animal-like anomalies in the
human structure, 40; on the cor-
relation of monstrosities, 44; on
the distribution of hair in man and
monkeys, 57; on the caudal ver-
tebre of monkeys, 58; on cor-
related variability, 60; on the
classification of man, 147; on the
long hair on the heads of species of
Semnopithecus, 151; on the hair in
monkeys, 152; on the develop-
ment of horns in female deer, 504;
and F, Cuvier, on the mandrill,
539; on Hylobates, 558, 559.

Geographical distribution, as evidence
of specific distinctions in man, 169.

Geometre, brightly co oured beneath,
315.

Geophagus, frontal protuberance of
male, 340, 345; eggs hatched by
she male, in the mouth or bran-
chial cavity, 345.

Georgia, change of colour in Germans
settled in, 196.

Geotrupes, stridulation of, 303, 304.

Gerbe, M., on the nest-building of
Crenilabrus massa and C. melops,
345,

Gerland, Dr., on the prevalence of
infanticide, 117, 577, 592; on the
extinction of races, 182.

Gervais, P., on the hairiness of the
gorilla, 57; on the mandrill, 538.
Gesture-language, 178.

Ghost-moth, sexual
colour in the, 316.

Gibbs, Sir D., on differences of the
voice in different races of men, 566.

Gibbon, Hoolock, nose of, 150.

Gibbons, voice of, 527.

Gill, Dr., male seals larger than
females, 219; sexual differences in
cents, 515

difference of

Giraffe, its mode of using the horns,
508; mute, except in the rutting
season, 526.

Girard, M., disputes descent of verti-

brates from Ascidians, 160; colour
of sponges and Ascidians, 261:
musky odour of Sphinx, 308.

Giraud-Teulon, on the cause of short
sight, 34.

Glanders, communicable to mau from
the lower animals, 7.

Glands, odoriferous, in mammals, 529,
530.

Glareola, double moult in, 390.

Glomeris lim)uta, difference of colour
in the sexes of, 274.

Glow-worm, female, apterous, 208 ;
luminosity of the, 277.

Gnats, dances of, 280; auditory powers
of, 569.

Gnu, sexual differences in the colour
of the, 536.

Goat, male, wild, falling on his horns,
508; male, odour emitted by, 529;
male, wild, crest of the, 531;
Berbura, mane, dewlap, &c., of the
male, 532; Kemas, sexual ditier-
ence in the colour of the, 536,

Goats, sexual differences in the horu.. of,
250; horns of, 235, 505; mode of
fighting of, 508; domestic, sexual
differences of, late developed, 237 ;
beards of, 531.

Goatsucker, Virginian, pairing of tue,
366

Gobies, nidification of 345.

God, want of the idea of, in some races
of men, 93.

Godron, M., on variability, 29; on
difference of stature, 31; on the
want of connexion between climate
and the colour of the skin, 192; on
the odour of the skin, 198; on the
colour of infants, 558.

Goldfinch, 371, 394; proportion of
the sexes in the, 248; sexual dif-
ferences of the beak in the, 309;
courtship of the, 401.

» North American, young of, 485

Gold-fish, 342.

Gomphus, proportions of the sexes tn,
1254; difference in the sexes of,
290.

Gonepteryx Rhamni, 312; sexual iif
tercaee of colour in, 322

DQ

@0DsIR,

46

INDEX.

RRaY.

Goodsir, Prof., on the affinity of the
lancelet to the ascidians, 159.

Goosander, young of, 467.

Goose, Antarctic, colours of the, 492.

, Canada, pairing with a Ber-

nicle gander, 414,

, Chinese, knob on the veak of
the, 426,

—, Egyptian, 364.

——, Sebastopol, plumage of, 385.

-——, Snow-, whiteness of the, 492.

, Spur-winged, 364,

Gorilla, 5613; semi-erect attitude of
the, 52; mastoid processes of the,
53; direction of the hair on the
arms of the, 151; manner of sit-
ting, 151; supposed to be a kind of
mandrill, 177 ; polygamy of the 217,
590, 591; voice of the, 527; cra-
nium of, 558; fighting of male,
562.

Gosse, P. H., on the pugnacity of the
male Humming-bird, 360.

, M., on the inheritance of artifi-
cial modifications of the skull, 603.

Gould, B. A., on variation in the
length of the legs in man, 26;
measurements of American soldiers,
30, 82; on the proportions of the
body and capacity of the lungs in
different races of men, 167; on the
the inferior vitality of mulattoes,
171.

——, J., on migration of swifts, 108 ;
on the arrival of male snipes before
the females, 212; on the numerical
proportion of the sexes in birds,
247; on Neomorpha Grypus, 359 5
on the species of Zustephanus, 359 ;
on the Australian musk-duck, 359 ;
on the relative size of the sexes in
Briziura lobata and Cincloramphus
cruralis, 362; on Lobivanellus loba-
tus, 366; on the habits of Menura
Alberti, 3713 on the rarity of song
in brilliant birds, 871; on Selav-
phorus plutycercus, 378; on the
Bower-birds, 381, 406; on the
ornamental plumage of the Hum-
ming-birds, 387 ; on the moulting
of the ptarmigan, 392; on the dis-
play of plumage by the male Hum-
ming-birds, 394; on the shyness of
adorned male birds, 403; on the
deroration of the bowers of Bower-

birds, 413; on the decoration of
their nests by Humming-birds. 413 ;
on variation in the genus: Cynun-
thus, 423; on the colour of the
thighs in a male parakeet, 424 ; on
Urosticte Benjamini, 442, 443; on
the nidification of the Orioles, 454°
on obseurely-coloured birds build
ing concealed nests, 454; on trogons
and kingfishers, 456; on Austra-
lan parrots, 458; on Australian
pigeons, 458; on the moulting of
the ptarmigan, 462; on the imma-
ture plumage of birds, 466 et seq.;
on the Australian species of Turniz,
473; on the young of Atthurus poly-
tmus, 487 ; on the colours of the bills
of toucans, 491; on the relative
size of the sexes in the marsupials
of Australia, 515; on the colours
of the Marsupials, 533.

Goureaux, on the stridulation of Mu-
tilla europea, 293.

Gout, sexually transmitted, 237.

Graba, on the Pied Ravens of the
Feroe Islands, 424; variety of the
Guillemot, 424.

Gradation of secondary sexual cha-
racters in birds, 430.

Grallatores, absence of secondary
sexual characters in, 219; dvukle
moult in some, 390.

Grallina, nidification of, 454,

Grasshoppers, stridulation of the, 286.

Gratiolet, Prof., on the anthropo-
morphous apes, 154; on the evo-
lution of the anthropomorphous
apes, 177; on the difference in the
development of the brains of apes
and of man, 203.

Gray, Asa, on the gradation of species
among the Compositz, 175.

, J. on the caudal vertebra

of monkeys, 58; on the presence

of rudiments of horns in the temale
of Cervulus moschatus, 504; on the
horns of goats and sheep, 505; on
the beard of the ibex, 531; on the

Berbura gozt, 5335 on sexual dif-

ferences in the coloration of Rodents,

534; ornaments of male sloth, 534;

on the colours of the Elands, 535;

on the Sing-sing antelope, 536;

on the colours of guats. 536; on the

hog-deer, 046.

GREATEST,

INDEX.

HACKEL.

647

Greatest happiness principle,” 120,

Greeks, ancient, 140.

Green, A. H., on beavers fighting,
500; on the voice of the beaver,
527.

Greenfinch, selected by a female
canary, 415,

Greg, W. R., on the effects of natural
selection on civilised nations, 133;
on the early marriages of the
poor, 138; on the Ancient Greeks,
141.

Grenadiers, Prussian, 29.

Grey, Sir G., on female infanticide in
Australia, 592.

Greyhounds, numerical proportion of
the sexes in, 215, 216; numerical
proportion of male and female
births in, 246, 258.

Grouse, red, monogamous, 219; pug-
nacity of young male, 366; pro-
ducing a sound by scraping their
wings upon the ground, 374; dura-
tion of courtship of, 405; colours
and nidification of, 455.

Gruber, Dr., on the occurrence of
the supra-condyloid foramen in the
humerus of man, 21; on division
of malar bone, 39; stridulation of
locust, 284,

Grus americanus, age of mature plu-
mage in, 483; breeding in im-
mature plumage, 484. :

virgo, trachea of, 374,

Gryllus campestris, 284; pugnacity
of male, 289.

domesticus, 284.

Gryp s, sexual differences in the beak
in, 359.

Guanacoes, battles of, 500; canine
teeth of, 514,

Guanas, strife for women among the,
562; polyandry among the, 593.
Guanche skeletons, occurrence of the
supra-condyloid foramen in the

humerus of, 22.

Guaranys, proportion of men and
women among, 244; colour of new-
born children of the, 557; beards
of the, 561.

Guenee, A., on the sexes of Hyp ry-
thra, 251 :

Guilding, L., on the stridulation of
the Tocustidm, 283

Guillemot, variety of the, 424.

Guinea, sheep of, with males only
horned, 234,

Guinea-towl, monogamous, 219 ; occas
sional polygamy of the, 220;
markings of the, 429.

Guinea-pigs, inheritance of the effects
of operations by, 603.

Gulls, seasonal change of plumage in,
492; white, 492.

Giinther, Dr., on paddle of Ceratodus,
37; on hermaphroditism in Serra-
nus, 162; on male fishes hatching
ova in their mouths, 163, 345; on
mistaking infertile female fishes for
males, 249; on the prehensile
organs of male Plagiostomous fishes,
331; spines and brushes on fishes,
331; on the pugnacity of the male
salmon and trout, 332; on the
relative size of the sexes in fishes,
3355 on sexual differences in fishes,
336 et seq.; on the genus Callin-
nymus, 337; on a protective re-'
semblance in a pipe-fish, 344; on
the genus Solenostoma, 346 ; on the
coloration of frogs and toads, 349;
combats of Testudo eleguns, 351;
on the sexual differences in the
Ophidia, 351; on differences of the
sexes of lizards, 354 ct seq.

Gynanisa Isis, ocellated spots of,
428.

Gypsies, uniformity of, in various
parts of the world, 193.

i.

Habits, bad, facilitated by familiarity,
123; variability of the force ot,
125,

Hackel, E., on the origin of man, 33
on rudimentary characters, 11; on
death caused by inflammation of
the vermiform appendage, 21; on
the canine teeth in man, 40; on
the steps by which man became a
biped, 52; on man as a member of
the Catarrhine group, 155; on the
position of the Lemurila, 157; un
the genealogy of the Mammalia,
158; on the lancelet, 159; on the
transparency of pelagic animals,
261; on the musical powers of
women, 573.

HAGEN, *

648

INDEX

HEMITRAGUS.

Hagen, H., and Walsh, B.D, on
American Neuroptera, 254.

Hair, development of, in man, 18;
character of, supposed to be deter-
mined by light and heat, 32; distri-
bution of, in man, 57, 600; possibly
removed for ornamental purposes,
58; arrangement and direction of,
151; of the early progenitors of
man, 160; different textare of, in
distinct races, 1675 and skin, cor-
relation of colour of, 1975; develop-
ment of, in mammals, 530 ; manage-
ment of, among different peoples,
575; great length of, in some
North American tribes, 580; elon-
gation of the, on the human head,
603.

Hairiness, difference of, in the sexes
in man, 559; variation of, in races
of men, 559.

Hairs and excretory pores, numerical
relation of, in sheep, 198.

Hairy family, Siamese, 601.

Halbertsma, Prof., hermaphroditism
in Serranus, 162.

Hamadryas baboon, turning over
stones, 101; mane of the male, 521.

Hamilton, C., on the cruelty of the
Kaffirs to animals, 118; on the
engrossment of the women hy the
Kaffir chiefs, 595.

Hammering, difficulty of, 49.
Hancock, A., on the colours of the
nudibranch Mollusca, 261, 264.
Hands, larger at birth, in the chil-
dren of labourers, 33; structure of,
in the quadrumana, 50; and arms,
freedom of, indirectly correlated

with diminution of canines, 53.

Handwriting, inherited, 88.

Handyside, Dr., supernumeiary mam-
rae in men, 37,

Harcourt, E. Vernon, on Fringilla
cannabina 394,

Harelda glucialis, 420.

Hare, protective colouring of the,
542,

Hares, battles of male, 500.

Harlan, Dr., on the difference be-
tween field- and house-slaves, 196.

Harris, J. M., on the relation of com-
plexion to climate, 195.

——, T. W., on the Katy-did locust,
483; on the stridulation of the

grasshoppers, 2563; on Q@cantius
nivalis, 289; on the colouring of
Lepidoptera, 37 £; on the colouring
of Saturnia Io, 316.

Harting, spur of the Ornithorhynchus.
502.

Hartman, Dr., on the singing of Cicada
septendeim, 282.

Hatred, persistence of, 112.
Haughton, S., on a variation of the
flexor pollicis longus in man, 42.
Hawks, feeding orphan nestling, 409.
Hayes, Dr., on the diverging of sledge-

dogs on thin ice, 75.

Haymond, R., on the drumming of the
male Tetrao umbellus, 375; on the
drumming of birds, 376.

Head, altered position of, to suit the
erect attitude of man, 55; hziriness
of, in man, 57; processes of, in
male beeties, 295; artificial alte-
rations of the form of the, 583.

Hearne, on strife for women among
the North American Indians, 561;
on the North American Indians’
noticn of female beauty, 578; re-
peated elopements of a North Ame
rican woman, 597.

Heart, in the human embryo, 9.

Heat, supposed effects of, 32,

Hectocotyle, 263.

Hedge warbler, 473; young of the,
481.
Heel, small projection of, in the

Aymara Indians, 35.

Hegt, M., on the development of the
spurs in peacocks, 236.

Heliconide, 308; mimicry of, by
other butterflies, 323.

Heliopathes, stridulation peculiar to
the male, 305.

Heliothria auriculsta, young of, 467,
468.

Helix pomatia, example of individual
attachment in, 263.

Hellins, J., proportions of sexes of
Lepidoptera reared by, 253.

Helmholtz, on pleasure cerived from
harmonies, 92; on the vibration of
the auditory hairs of crustacea,
568; the physiology of harmony,
659.

Hemiptera, 281.

‘Temit: aus, beardless in beth sc tea,
531,

HEMSBACII.

INDEX.

TLORSLS,

649

Hemsbach, M. von, on medial mamma
in man, 37,

Hepburn, Mr., on the autumn song of
the water-ouzel, 370,

Hepialus humuli, sexual difference of
colour in the, 316.

Herbs, poisonous, avoided by animals,

6

Hermaphreditism of embryos, 161.

Herodius bubuicus, vernal moult of,
393.

Heron, Sir R., on the habits ot pea-
fowl, 418, 419, 443,

love-gestures of a, 380

Herons, decomposed feathers in, 385 ;
breeding plumage of, 391, 392;
young of the, 481; sometimes
dimorphic, 484; continued growth
of crest and plumes in the males of
some, 485; change of colour in
some, 494,

Hesperomys cognatus, 568.

Heterina, proportion of the sexes in,
254; difference in the sexes of,
290.

Fleterocerus, stridulation of, 302.

Hewitt, Mr., on a game-cock killing
a kite, 363; on the recognition of
dogs and cats by ducks, 412; on
the pairing of a wild duck with a
pintail drake, 415; on the court-
ship of fowls, 417 ; on the coupling
of pheasants with common hens,
420,

Hilgendorf, sounds produced by crus-
taceans, 274,

Hindoo, his horror of breaking his
caste, 122, 124.

Hindoos, local difference of stature
among, 31; difference of, from
Europeans, 192; colour of the
beard in, 558.

Hipparchia Janira, 319; instability
of the ocellated spots of, 428.

Hippocampus, development of, 163;
marsupial receptacles of the male,
346.

— minor, 202.

Hippopotamus, nakedness of, 56.

Hips, proportions of, in soldiers and
sailors, 32.

Hodgson, S., on the sense of duty, 97.

Hoffberg, on the horns of the rein-
deer, 503; on sexual preferences
shown by reindeer, 525.

Hoffman, Prof., protective colours,
281; fighting of frogs, 350.

Hog-deer, 546

Hog, wart-, 519; river-, 520.

Holland, Sir H., on the effects of new
diseases, 182.

Homologous structures,
variation of, 43.

Homoptera, 281; stridulation of the,
and Orthoptera, discussed, 288.

Honduras, Quiscalus major in, 248.

Honey-buzzard of India, variation in
the crest of, 424.

Honey-suckers, moulting of the, 392;
Australian, nidification of, 454.

Honour, law of, 121.

Hooker, Dr., forbearance of elephant
to his keeper, 104; on the colour :
of the beard in man, 558,

Hookham, Mr., on mental concepts in
animals, 83.

Hoolock Gibbon, nose of, 150.

Hoopoe, 371; sounds produced by the
male, 376.

Hoplopterus armatus, wing-spurs of,
366.

Hornbill, African, inflation of the
neck-wattle of the male during
courtship, 383.

Hornbills, sexual difference in the
colour of the eyes in, 425; nidif-
cation and incubation of, 454.

Horne, C., on the rejection of a
brightly-coloured locust by lizards
and birds, 289.

Horns, sexual differences of, in sheep
and goats, 230; loss of, in feniule
merino sheep, 231; development
of, in deer, 233; development of,
in antelopes, 234; from the head
and thorax, in male beetles, 297 ;
of deer, 503, 506, 515; and canine
teeth, inverse development of,
514,

correlated

Horse, fossil, extinction of the, in

South America, 191; polygamous,
217; canine teeth of male, 5025
winter change of colour, 542.
Horses, rapid increase of, in South
America, 47; diminution of canine
teeth in, 53; dreaming, 74; of
the Falkland Islands and Pam-
pas, 181; numerical proportion of
the sexes in, 215, 216; lighter in
winter in Siberia, 229; sexual

650

HOTTENTOT,

INDEX.

HYDROPORUB.

preferences in, 524; pairing pre-
ferently with those of the same
colour, 540; numerical proportion
of male and female births in, 245;
formerly striped, 547.

Hottentot women, peculiarities of, 174,

Hottentots, lice of, 1703; readily be-
come musicians, 570; notions of
female beauty of the, 578; com-
pression of nose by, 583.

Hough, Dr. S., men’s temperature
more variable than women’s, 224;
propurtion of sexes in man, 243,

House-slaves, difference of, from field-
slaves, 196.

Houzeau, on the baying of the dog,
75; on reason in dogs, 76; birds
killed by telegraph wires, 80; on
the cries of domestic fowls and
parrots, 85, 87; animals feel no
pity, 102; suicide in the Aleutian
islands, 117.

Howorth, H. H., extinction of savages,
183.

Huber, P., on ants playing together,
69; on memory in ants, 74; on the
intercommunication of ants, 89 ; on
the recognition of each other by
ants after separation, 292.

Hue, on Chinese opinions of the ap-
pearance of Europeans, 578.

Huia, the, of New Zealand, 208.

Human, man classed alone in a, king-
dom, 147.

sacrifices, 96.

Humanity, unknown among some
savages, 118; deficiency of, among
savages, 123,

Humboldt, A. von, on the rationality
of mules, 78; on a parrot preserv-
ing the language of a lost tribe,
181; on the cosmetic arts of
savages, 574; on the exaggeration
of natural characters by man, 582;
on the red painting of American
Tndians, 583.

Hume, D., on sympathetic feelings,
109, :

Bumming-bird, racket-shaped feathers
in the tail of a, 384; display of |
plumage by the male, 394.

Hamming-birds, ornament their nests,
92. 413; polygamous, 219; pro-
portion of the sexes in, 248, 488 ;
sexual differeaces in, 359, 442; |

pugaacity of male, 360; modified
primaries of male, 378; coloratioa
of the sexes of, 387; display by, 443;
nidification of the, 453; colours of
female, 453; young of, 487.

Humphreys, H. N., on the habits of
the stickle-back, 220, 332.

Hunger, instinct of, 112.

Huns, ancient, flattening of the nose
by the, 583.

Hunter, J., on the number of species
of man, 174; on secondary sexual
characters, 207; on the general
behaviour of female animals during
courtship, 222; on the muscles of
the larynx in song-birds, 371; on
the curled frontal hair of the bull,
531; on the rejection of an ass by
a female zebra, 540.

Hunter, W. W., on the recent rapid
increase of the Santali, 45; on the
Santali, 192.

Huss, Dr. Max, on mammary glands,
162, :

Hussey, Mr., on a partridge distin-
guishing persons, 412.

Hutchinson, Col., example of reason-
ing in a retriever, 78.

Hutton, Capt., on the male wild goat
falling on his horns, 507,

Huxley, T. H., on the structural
agreement of man with the apes,
2; on the agreement of the brain
in man with that of lower animals,
6; on the adult age of the orang,
8; on the embryonic development
of man, 9; on the origin of man,
3, 11; on variation in the skulls of
the natives of Australia, 26; on
the abductor of the fifth meta-
tarsal in apes, 42; on the nature
of the reasoning power, 77; on the
position of man, 150; on the sub-
orders of primates, 152; on the
Lemuride, 157; on the Dinosauria,
158 ; on the amphibian affinities of
the Ichthyosaurians, 159; on vari-
ability of the skull in certain races
of man, 1743; on the races of man,
1765; supplement on the brain, 199.

Hybrid birds, production of, 414,

Hydrophobia communicable between

_ man and the lower animuls, 7.

Hydroporus, dimorphism of femslee

of, 276.

HYELAPIIUS,

INDEX.

INSECTIVORA.

651

Byelaphus porcinus, 546.
Hygrogonus, 345,
dyla, singing species of, 350.
Hylobates, absence of the thump in, 51 ;
upright progression of some species
of, 52; maternal affection in a,
70; direction of the hair on the
arms of species of, 151; temales cf,
less hairy below than males, 558.
— agilis, 51; hair on the arms of,
1513; musical voice of the, 527;
superciliary ridge of, 558 ; voice of,
567.
hoolock, sexual difference of
colour in, 537. :
lar, 51; hair on the arms of,
15). ‘ :
— leucisens, 51; song of, 568,
syndactylus, 51; laryngeal sac
of, 527. #
Hylophila prasinana, 308.
Hymenoptera, 291; large size of the
cerebral ganglia in, 54; classifica-
tion of, 148; sexual differences in
the wings of, 277; aculeate, rela-
tive size of the sexes of, 279.
Hymenopteron, parasitic, with a
sedeptary male, 221.
Hyomoschus ajuati us, 547.
Hyperythra, proportion of the sexes
in, 251,
Hypogymma dispar, sexual difference
of colour in, 316.
Typopyra, coloration of, 315.

I

Ibex, male, falling on his horns, 508 ;
beard of the, 531.

Ibis, white, change of colour of
naked skin in, during the breeding,
season, 389 ; scarlet, young of the,
481.

— tantalus, age of mature plumage
in, 483; breeding in immature
plumage, 484,

tbises, decomposed feathers in, 385;
white, 492; and black, 493.

Ichneumonida, difference of the sexes
in, 292.

Ichthyopterygia, 37. -

‘chthyosaurians, 159,

Idiots,.microcephalous, their charac-
ters and habits, 35; hairiness and
animal nature of their actions, 36 ;

microcephalous, imitative faculties
of, 87.

Iguana tuberculata, 354,

Iguanas, 354,

Illegitimate and legitimate children,
proportion of the sexes in, 244.

Imagination, existence of, in anima.s,
74.

Imitation, 68; of man by monkeys,
72; tendency to, in monkeys, micro-
cephalous idiots and savages, 87 ;
influence of, 129.

Immature plumage of birds, 463, 466.

Implacentata, 157.

Implements, employed by monkeys,
81; fashioning of, peculiar to
man, 82.

Impregnation, period of, influence of,
upon sex, 245,

Improvement, progressive, man alone

~ supposed to be capable of, 79.

Incisor teeth, knocked out or filed by
some savages, 575.

Increase, rate of, 44; necessity of
checks in, 47.

Indecency, hatred of, a modern virtue,
119.

India, difficulty of distinguishing the
native races of, 167; Cyprinida
of, 343; colour of the beard iu
races of men of, 558.

Indian, North American, honoured
for scalping a man of another tribe,
117. .

Individuality, in animals, 85.

Jndopicus carlotta, colours of the
sexes of, 458.

Infanticide, prevalence of, 46, 117,
256 ; supposed cause of, 577; pre:
valence and causes of, 591 et sey.

Inferiority, supposed physical, of
mun, 64,

Inflammation of the bowels, oceur-
rence of, in Cebus Azara@, 7.

Inheritance, 27; of long and shcrt
sight, 33; of effects of use of vocal
and mental organs, 88; of mora)
tendencies, 123, 126; laws of,
227; sexual, 232; sexually limi-
ted, 444.

Inquisition, influence of the, 141.

Insanity, hereditary, 28.

Insect, fossil, from the Devonian, 289.

Insectivora, 534; absence of seco dary
sexual characters in, 218.

652

INSECTS.

INDEX.

JERDON.

Insects, relative size of the cerebral |
ganglia in, 54; male, appearance
of, before the females, 212; pursuit
of female, by the males, 221; period
of development of sexual characters
in, 236; secondary sexual cha-
racters of, 274; stridulation, 566.

Insessores, vocal organs of, 370.

Instep, depth of, in soldiers and
sailors, 32.

Instinct and intelligence, 67.

» migratory, vanquish’ng the
maternal, 107, 113.

Instinctive actions, the result of in-
heritance, 105.

impulses, difference of the force
of, 110, 111; and moral impulses,
alliance of, 110.

Instincts, 663; complex origin of,
through natural selection, 67;
possible origin of some, 67; ac-
quired, of domestic animals, 104 ;
variability of the force of, 107;
difference of force between the
social and other, 111, 126; utilised
for new purposes, 571.

Instrumental music of birds, 375, 378.

Intellect, influence of, in natural
selection in civilised society, 136.

Intellectual faculties, their influence
on natural selection in man, 127;
probably perfected through natural
selection, 128.

Intelligence, Mr. H. Spencer on the
dawn of, 67.

Intemperance, no reproach among
savages, 119; its destructiveness,
137.

Intoxication in monkeys, 7.

Iphias glaucippe, 313.

Iris, sexual difference in the co.our of
the, in birds, 383, 425.

Ischio-pubic muscle, 41.

Tthayinis cruentus, number of spurs
in, 364.

Tulus, tarsal suckers of the males of,
274

J.
Jackals learning from dogs to bark,
73.

Jack-snipe, coloration of the, 491

Jacquinot, on the number of species
of man, 174.

Jaeger, Dr., length of tones increased

from carrying weights, 32; on the
ditfculty of approaching herds of
wild animals, 100; male Silver-
pheasant, rejected when his plu-
mage was spoilt, 419.

Jaguars, black, 539.

Janson, E. W., on the proportions of
the sexes in Tomicus villusus, 2535
on stridulant beetles, 802.

Japan, encouragement of licentious-
ness in, 46.

Japanese, general beardlessness of the,
560; aversion of the, to whiskers,
581.

Jardine, Sir W., on the Argus phea-
sant, 384, 403.

Jarrold, Dy., on modifications of the
skull induced by unnatural position,
56.

Jarves, Mr., on infanticide in the
Sandwich Islands, 257,

Javans, relative height of the sexes
of, 559; notions of female beauty,
580.

Jaw, influence of the muscles of the,
upon the physiognomy of the apes,
54,

Jaws, smaller proportionately to the
extremities, 33; influence of food
upon the size of, 33; diminution
of, in man, 53; in man, reduced
by correlation, 562.

Jay, young of the, 481; Canada,
young of the, 481.

Jays, new mates found by, 407; dis-
tinguishing persons, 412,

Jeffreys, J. Gwyn, on the form of the
shell in the sexes of the Gastero-
poda, 262; on the influence of light
upon the colours of shells, 263.

Jelly-fish, bright colours of some,
260.

Jenner, Dr., on the voice of the rook,
375; on the finding of new mates by
magpies, 407; on retardation of the
generative functions in birds, 409.

Jenyns, L., on the desertion of their
young by swallows, 108; on male
birds singing after the proper
season, 409.

Jerdon, Dr., on birds dreaming, 74;
on the pugnacity of the male bul-
bul, 360; on the pugnacity of the
male Ortygornis gularis, 363; on
the spurs of Galloperdiz, 364; o8

JEVONS.

INDEX.

KIRBY,

653

the habits of Lobivanellus, 366 ; on
the spoonbill, 374; on the drum-
ming of the Kalij-.heasant, 376;
on Indian bustards, 378; on (tis
bengalensis, 381; on the ear-turts
of Sypheotides auritus, 384; on the
double moults of certain birds, 391 ;
on the moulting of the honey-
suckers, 392; on the moulting of
bustards, plovers, and drongos, 393;
on the spring change of colour in
some finches, 393; on display in
male birds, 394; on the display of
the under-tail coverts by the male
bulbul, 402; on the Indian honey-
buzzard, 424; on sexual differences
in the colour of the eyes of horn-
bills, 425; on the markings of the
Tragopan pheasant, 428; on the
niditication of the Orioles, 453 ; on
the nidification of the hornbills,
454; on the Sultan yellow-tit, 458 ;
on Paleornis javanicus, 461 ; on the
immature plumage of birds, 465
et seg.; on representative species of
birds, 468 ; on the habits of Zurniz,
476; on the continued increase of
beauty of the peacock, 485; on
coloration in the genus Paleornis,
494,

Jevons, W. S., on the migrations of
man, 47.

Jews, ancient use of flint tools by the,
145; uniformity of, in various
parts of the world, 193; numerical
proportion of male and female
births among the, 243; ancient,
tattooing practised by, 574.

Johnstone, Lieut., on the Indian ele-
phant, 218.

Jollofs, fine appearance of the, 587.

Jones, Albert, proportion of sexes of
Lepidoptera, reared by, 253.

Juan Fernandez, hummirg-birds of,
487,

Junonia, sextial differences of colour-
ing in species of, 310.

Jupiter, comparison with Assyrian
effigies, 581.

x.

Katfir skull, occurrence of the dia-
stema in a, 40.
Kaflirs, their cruelty to arifnals, 118 ;

lice of the, 170; colour ot the,
579; engrossment of the hend-
somest women by the chiefs of the,
595; marriage-customs of the, 598.

Kalij-pheasant, drumming of the
male, 375; young of, 468.

Kallima, resemblance of, to a withered
leaf, 311,

Kalmucks, general beardlessness of,
560; aversion of, to hairs on the
face, 5813; marriage-customs of
the, 598.

Kangaroo, great red, sexual difference
in the colour of, 533,

Kant, Imm., on duty, 97; on self-
restraint, 110; on the number of
species of man, 174.

Katy-did, stridulation of the, 283.

Keen, Dr., on the mental powers of
snakes, 352,

Keller, Dr., on the difficulty of
fashioning stone implements, 49.
Kent, W. S., elongation of dorsal fin
ot Callionymus lyra, 336; court-
ship of Labrus mixtus, 341; colours
and courtship of Cuntharus lineatus,

341,

Kestrels, new mates found by, 408.

Kidney, one, doing double work in
disease, 32,

King, W. R., on the vocal organs of
Tetrao cupido, 371; on the drum-
ming of grouse, 376; on the rein-
deer, 503; on the attraction of
male deer by the voice of the
female, 526.

King and Fitzroy, on the marriage
customs of the Fuegians, 599.

King-crows, nidification of, 453.

Kingfisher, 371; racket-shaped feathers
in the tail of a, 384.

Kingfishers, colours and nidification
of the, 455, 457, 459; immature
plumage of the, 467, 468; young
of the, 481.

King Lory, 457; immature plumage
of the, 467.

Kingsley, C., on the sounds produced
by Umbrina, 347.

Kirby and Spence, on sexual differ-
ences in the length of the snout in
Curculionidz, 208; on the court-
ship of insects, 221; on the elytra
of Dytiscus, 276; on peculiarities
in the legs of male insects, 276;

KITE,

654

INDEX.

LANIUA.

on the relative size of the sexes in
insects, 279; on the Fulgorida,
281; on the habits of Vermuites,
2915 on difference of colour in the
sexes of beetles, 294 ; on the horns
of the male lamellicorn beetles,
297 ; on hornlike processes «m male
Curculionidae, 299; on the pug-
nacity of the male stag-beetle, 299.

Kite, killed by a game-cock, 363.

Knot, retention of winter plumage hy
the, 391

Knox, R., on the semilunar fold, 17;
on the occurrence of the supra-
condyloid foramen in the humerus
of man, 21; on the features of the
young Memnon, 168.

Koala, length of the cecum in, 20.

Kobus ellipsiprymnus, proportion of
the sexes in, 247.

KOlreuter, on the sterility of hybrid
plants, 172.

Koodoo, development of the horns of
the, 234; markings of the, 543.
Koppen, F. T., on the migratory lo-

cust, 283.

Kordofan, protuberances artificially
produced by natives of, 574.

Koraks, marriage customs of, 598.

Kérte, on the proportion of sexes in
locusts, 254; Russian locusts, 283.

Kovalevsky, A., on the affinity of
the Ascidia to the Vertebrata, 159,
160.

—, W., on the pugnacity of the
male capercailzie, 363; on the
pairing of the capercailzie, 367.

Kranve, on a convoluted body at the
extremity of the tail in a Macacus
and a cat, 23.

Kupffer, Prof., on the affinity of the
Ascidia to the Vertebrata, 160.

L.

La'idocera Darwinii, preheusile organs
of the male, 266

Zabrus, splendid colours of the species
of, 342.

mistus, sexual differences in,

387, 841.

pavo, 342,

Lacertila, sexual differences cf, 354,

Latresnave, M. de, on birds of parae
dise, 38E.

Lamarck, on the origin of man, 3.

Lamellibranchiata, 262.

Lamellicorn beetles, horn-like pro-
cesses from the head and thorax of,
295, 298; influence of sexual selec-
tion on, 301.

Lamellicornia, stridulation of, 303.

Lamont, Mr., on the tusks of the
walras, 502; on the use of its
tusks by the walrus, 513; on the
bladder-nose seal, 528.

Lampornis porphyrurus, colours of
the female, 454.

Lampyrida, distasteful to mammais,
277

Lancelet, 159, 165.

Landois, H., gnats attracted by sound,
280; on the production of sound
by the Cicada, 281; on the stridu-
lating organ of the crickets, 28+ ;
on Decticus, 285; on the stridula-
ting organs of the Acridiide, 286 ;
stridulating apparatus in Orthop-
tera, 288; suunds produced by
Atropus, 291; on the stridulation
of Necrophorus, 302; on the stridu-
lant organ of Cerambyx heros, 303 ;
on the stridulant organ of Geo-
trupes, 3033; on the stridulating
organs in the Coleoptera, 304; on
the ticking of Anobium, 306.

Landor, Dr., on remorse for not obey
ing tribal custom, 114.

Language an art, 86; articulate, origin
of, 86; relation of the progress of,
to the development of the brain,
87; effects of inheritance in pro-
duction of, 88; complex structure
ot, among barbarous nations, 91;
natural selection in, 91; gesture,
178 ; primeval, 180; of a lost tribe
preserved by a parrot, 181.

Languages, presence of rudiments in,
90; classification of, 90; variability
of, 90; crossing or blending of, 90;
complexity of. no test of perfection
or proof of special creation, 92; re-
semblance of, evidence of commu-
nity of origin, 148.

and species, identity of evidence
of their gradual development, 90.

Fanius, 462; characters of young,
464.

——- rufus, anomalous young on
482.

LANKESTER.

INDEX.

LIBELLULID &,

655

Lankester, E. R., on comparative lon-
gevity, 133, 136; on the destruc-
tive effects of intemperance, 137.

Lanugo, of the human fetus, 19,
600.

Lapponian language, highly artificial,
91.

Lark, proportion of the sexes in the,
248; female, singing of the, 370.

Larks, attracted by a mirror, 413.

Eartet, E., comparison of cranial ca-
pacities of skulls of recent and
tertiary mammals, 55; on the size
of the brain ia mammals, 81; on
Dryopithecus, 155° on vre-historic
flutes, 570.

Larus, seasonal change of plumage in,
492,

Larva, luminots, of a Brazilian beetle,
278.

Larynx, muscles of the, in song-birds,
371.

Lasiocampa quercus, attraction of
males by the female, 252; sexual
difference of colour in, 316.

Latham, R. G., on the migrations of
man, 48,

Latooka, perforation of the lower lip
by the women of, 576. ;

Laurllard, on the abnormal division
of the malar bone in man, 39.

Lawrence, W., on the superiority of
savages to Europeans in power of
sight, 33; on the colour of negro
infants, 558; on the fondness of
savages for ornaments, 578 5 on
beardless races, 581; on the beauty
of the English aristocracy, 586.

Lavard, E. L., on an instance of ra-
tionality in a cobra, 352; on the
pugnacity of Gallus Stanley?, 363.

Laycock, Dr., on vital periodicity, 8;
the1oid nature of idiots, 36.

Leaves, autumn, tints useless, 262.

Lecky, Mr., on the sense of duty, 97 ;
on suicide, 117; on the praetice of
celibacy, 119; his view of the
crimes of savages, 119; on the
gradual rise of morality, 125.

Leconte, J. L., on the stridulant organ
in the Coprini and Dynastini, 303.

Jee, HL, on the numerical proportion
of the sexes in the trout, 249.

Leg, calf of Lhe, artificia!.y modified,
574,

Legitimate and illegitimate children,
proportion of the sexes in, 244,

Legs, variation of the length of the, in
man, 26; proportions of, in sol-
diers and sailors, 32; front, atro-
phied in some male butterflies, 277 ;
peculiarities of, in male in.ects, 277.

Leguiy, on the occurrence of the
supra-condyloid foramen in the
humerus of man, 22.

“Lek” of the black-cock and caper-
cailzie, 405,

Lemoine, Albert, on the origin of lan-
guage, 87.

Lemur macaco, sexual difference of
colour in, 537.

Lemurida, 152; ears of the, 15;
variability of the muscles in the,
41; position and derivation of the,
157; their origin, 165.

Lemurs, uterus in the, 38.

Lenguas, disfigurement of the ears of
the, 575.

Leopards, black. 539.

Lepidoptera, 307 ; numerical propor-
tions of the sexes in the, 250;
colouring of, 308; ocellated spots
of, 427.

Lepidosiren, 159, 165.

Leptalides, mimicry of, 325.

Leptorhynchus angustatus, pugnacity
of male, 299.

Leptura testacea, difference of colour
in the sexes of 294.

Leroy, on the wariness of young foxes
in hunting-districts, 80; on the
desertion of their young by swal-
lows, 108.

Leslie, D., marriage customs of Kaffirs,
598.

Lesse, valley of the, 22.

Lesson, on the birds of paradise, 219,
408; on the sea-elephant, 5:28.

Lessona, M., observations on Serra, :3
162,

Lethrus cephalotes, pugnacity of the
males of, 297, 300.

Leuckart, R., on the vesicula prosta-
tica, 24; on the influence of the
age of parents on the sex of off-
spring, 245,

Levator cluvicule muscle, 42.

Lidelinia depressa, colour of the tnaie,
290.

Libellulide, relative size of the sexes

656

LICE,

INDEX.

LUBBOCK.

of, 279; difierence in the sexes of,
290.

Lice of domestic animals and man,
169.

Licentiousness, a check upon popula-
tion, 46; prevalence of, amoag
savages, 119.

Lichzenstein, on Chera progne, 419.

Life, inheritance at corresponding
periods of, 228, 232.

Light, effects on complexion, 32; in-
fluence of, upon the colours of
shells, 263.

Lilford, Lord, the ruff attracted by
bright obiects, 413.

Limosa lapponica, 478.

Linaria, 462.

montuna, 248,

Lindsay, Dr. W. L., diseases commu-
nicated from animals to man, 73
madness in animals, 79; the dog
considers his master his Ged, 96.

Linnzus, views of, as to the position
of man, 149.

Linnet, numerical proportion of the
sexes in the, 248; crimson fore-
head and breast of the, 394; court-
ship of the, 401.

Lion, polygamous, 218; mane of the,
defensive, 521; roaring of the, 526.

Lions, stripes of young, 464.

Lips, piercing of the, by savages, 575.

Li'hobius, prehensile appendages of
the female, 274.

Lithosia, coloration in, 314,

Littorina littorea, 262.

Livingstone, Dr., mauner of sitting of
gorilla, 151; on the influence of
dampness and dryness on the colour
of the skin, 193; on the liability
of negroes to tropical fevers after
residence in a cold climate, 194;
on the spur-winged gaose, 364; on
weaver-birds, 376; on an African
night-jar, 384, 403 ; on the battle-
scars of South African male mam-
mals, 500; on the removal of the
upper incisors by the Batokas, 575;
on the perforation of the upper lip
by the Makalolo, 576; on the
Banyai, 579.

Livonia, numerical proportion of male
and female births in, 215, 243.

Lizards, relative size of the sexes
of, 354; gular pouches of, 354.

Lloyd, L., on the polygamy of the
capereailzie and bustard, 219; on
the numerical proportion of the
sexes in the capercailzie and black-
cock, 248; on the salmon, 333;
on the colours of the sea-scorpion,
337; on the pugnacity of male
grouse. 364; on the capercailzie
and black-cock, 366, 370; on the
call of the capercailzie, 375; on
assemblages of grouse and snipes,
405; on the pairing of a shield-
drake with a common duck, 414;
on the battles of seals, 500; on the
elk, 507.

Lobivanellus, wing-spurs in, 306.

Local influences, effect of, upon sta-
ture, 31.

Lockwood, Mr., on the development
of Hippocampus, 163.

——, Rev. S., musical mouse, 568.

Locust, bright-coloured, rejected by
lizards and birds, 289. :

, migratory, 283; selection by
female, 283.

Locusts, proportion of sexes in, 254;
stridulation of, 284,

Locustide, stridulation of the, 282,
284; descent of the, 285.

Longicorn beetles, difference of the
sexes of, in colour, 294; stridula-
tion of, 303.

Lonsdale, Mr., on an example of per
sonal attachment in Melia pomutia,
262.

Lophobranchii, marsupial receptacles
of the males, 346.

Lophophorus, habits of, 420.

Lophorina atra, sexual difference in
coloration of, 491.

Lophornis ornatus, 387

Lord, J. K., on Salm lycacdon, 333.

Lory, King, 457 ; immature plumage
of the, 467.

Love-antics and dances of birds, 380.

Lowne, B. T., on Jfusea vomitoria,
54, 280.

Lowia, characters of young of, 464.

Lubbock, Sir J., on the antiquity of
man, 2; on the origin of man, 3;

on the mental capacity of savages,

65; on the origin of implements,

82; on the simplification of lan-

guages, 92; on the absence of the

idea of God among certain races ai

LUCANIDE,

INDEX..

MACGILLIVRAY.

657

men, 94; on the origin of the
belief in spiritual agencies, 95;
on superstitions, 96; on the sense
of duty, 97; on the practice of
burying the old and sick among
the Fijians, 102; on: the im-
morality of savages, 119; on Mr.
Wallace's claim to the origination
of the idea of natural selection,
49; on the absence of remorse
among savages, 131; on the former
barbarism of civilised nations, 143 ;
on improvements in the arts among
savages, 144; on resemblances of
the mental characters in different
races of men, 1783; on the arts
practised by savages, 179; on the
power of counting in primeval man,
180; on the prehensile organs of
the male Labidocera Darwinii, 266 ;
on Chloéon, 274; on Smyntiu us
luteus, 279; finding of new mates
by jays, 407; on strife for women
among the North American Indians,
5613; on music, 570; on the orna-
mental practices of savages, 574 ;
on the estimation of the beard
among the Anglo-Saxons, 581;
on artificial deformation of the
skull, 583; on “communal mar-
riages,” 587, 588; on exogamy,
589, 592; on the Veddahs, 591;
on polyandry, 593,

Lucanida, variability of the mandibles
in the male, 300.

Lucanus, large size of males of, 278.

cervus, numerical proportion
of sexes of, 253; weapons of the
male, 299. Per

—— elaphus, use of mandibles of,
300; large jaws of male, 275.

uucas, Prosper, on pigeons, 418; on
sexual preference in horses and
bulls, 525,

. unar periods, 8, 164.

Lund, Dr., on skulls found ‘n Bra-
zilian caves, 168

Lungs, enlargement of, in the Qui-
chua and Aymara Indians, 34;
a modified swim-bladder, 161;
different capacity of in races of
man, 167.

Luminosity in insects, 277.

Luschka, Prof., on the termination of
the coce7x, 23,

43

Luxury, expectation of life unin-
fluenced by, 136.

Lycena, sexual differences of colour-
ing in species of, 310.

Lyell, Sir C., on the antiquity of

“man, 23; on the origin of man,
3; on the parallelism of the de-
velopment of species and languages,
90; on the extinction of lan-
guages, 90; on the Inquisition,
141; on the fossil remains of ver-
tebrata, 157; on the fertility of
mulattoes, 171.

Lynx, Canadian, throat-ruff of the.
521.

Lyre-bird, assemblies of, 406.

M.

Macacus, ears of, 15; convoluted
body in the extremity of the tail
of, 23; variability of the tail in
species of, 58; whiskers uf species
of, 531

brunneus, 59. :

cynomoljus, superciliary ridge

of, 558; beard and whiskers of,

becoming white with age, 559.

ecaudatus, 60.

—— lasi.tus, facial spots of, 550,

radiatus, 151.

rhesus, sexual difference in the
colour of, 539, 550.

Macalister, Prof., on variations of
the palmaris accessorius muscle,
27; on muscular abnormalities in
man, 42, 43; on the greater varia-
bility of the muscles in men than
in women, 223.

Macaws, Mr. Buxton’s observations
on, 102; screams of, 375.

McCann, J., on mental individuality,
84,

McClelland, J., on the Indian Cypri-
nid, 343.

Macculloch, Col., on an Indian vil-

' lage without any female children,
592,

, Dr., on tertian ague ina dog, 8.

Macgillivray, W., on the vocal organs
of birds, 90; on the Egyptian
goose, 365; on the habits of wooad-
peckers, 376 ; on the habits of the
snipe, 877; on the whitethroas.
381; on the moulting of the snipes:

MACIHETES,

658

INDEX.

MAMMALIA.

891; on the moulting of the
Anatidz, 393; on the finding of
new mates by magpies, 407; on
the pairing of a blackbird and
thrush, 414; on pied ravens, 424;
on the guillemots,-424; on the
colours of the tits, 458; on the
immature plumage of birds, 466
ef seq.

Ma-hetes, sexes and young of, 485 ;

pugnaz, supposed to be polyga-
mous, 219; numerical proportion
of the sexes in, 248; pugnacity of
the male, 360; double moult in, 390.

Mclntosh, Dr. colours of the Nemer-
tians, 265,

McKennan, marriage
Koraks, 598.

Mackintosh, on the moral sense, 97.

MacLachlan, R., on Apatania mulie-
bris and Bureus hyemalis, 254;
on the anal appendages ot male
insects, 275; on the pairing of
dragon-flies, 279 ; on dragon-flies,
290, 291; on dimorphism in
Agrion, 291; on the want of pug-
Bacity in male dragon-flies, 291 ;
colour of ghost-moth in the Shet-
land Islands, 316,

McLennan, Mr., on infanticide, 46,
591; on the origin of the belief in
spiritual agencies, 94; on the pre-
valence of licentiousness among
savages, 119, 588; on the primi-
tive barbarism of civilised nations,
148; on traces of the custom of
the forcible capture of wives, 144,
592; on polyandry, 593.

Macnamara, Mr., susceptibility of
Andaman islanders and Nepdlese
to change, 188.

McNeill, Mr., on the use of the ant-
lers of deer, 510; on the Scotch
deerhound, 516; on the long hairs
on tne throat of the stag, 522; on
the bellowing of stags, 526. a

Macropus, courtship of, 341.

Macrorhinus pro'vsvideus, structure
of the nose of, 528.

Magpie, power of speech of, 90;
nuptial assemblies of, 406; new
mates found by, 407; stealing
bright objects, 413; young of the,
481; coloration of the, 493,

Magpies, vocal orga.:s of the, 370.

customs of

Maillard, M., on the proportion of
the sexes in a species of Papilio
from Bourbon, 250.

Maine, Sir Henry, on the absorption
of one tribe by another, 128; a
desire for improvement not gener .l,
132,

Major, Dr. C. Forsyth, on fossil
Italian apes, 155; skull of Bes
etruscus, 505; tusks of miocene
pigs, 521.

Makalolo, perforation of the upper
lip by the, 576.

Malar bone, abnormal division of, in
man, 39.

Malay, Archipelago, marriage-cus-
toms of the savages of the, 598.
Malays, line of separation between
the Papuans and the, 169; general
beardlessness of the, 560; staining
of the teeth among, 574; aversion
of some, to hairs on the face,

581.

and Papuans, contrasted cha-
racters of, 168.

Male animals, struggles of, for the
possession cf the temales, 212, 213 ;
eagerness of, in courtship, 221,
222; generally more modified than
female, 221, 223; differ in the, same
way trom females and young, 232.

characters, developed in temales,

227; transfer of, to female birds,

aq ls

, sedentary, of a hymenopterour
parasite, 221.

Malefactors, 137.

Males, presence of rudimentary female
organs in, 162,

and females, comparative num-
bers of, 213, 215; comparative
mortality of, while young, 216.

Malherbe, on the woodpeckers, 458.

Mallotus peronii, 331.

villosus, 331.

Malthus, T., on the rate of increase
of population, 44, 45. 46,

Maluridz, nidification of the, 454.

Malurus, young of, 485.

Mamma, 208; rudimentary, in male
mammals, 11, 23, 161, 162, 163;
supernumerary, in women, 36; of
male human subject, 37.

Mammalia, Prof. Owen’s classificatior
of, 148; genealogy of the, 156.

MAMMALS.

INDEX,

MAYHEW.

659

Mammals, recent and tertiary, com-
parison of cranial capacity of, 553
nipples of, 162; pursuit of female,
by the males, 221; secondary sexual
characters of, 500; weapons of,
501; relative size of the sexes of,
515; parallelism of, with birds in
secondary sexual characters, 5415
voices of, used especially during the
breeding season, 567.

Han, variability of, 26; erroneously
regarded as more domesticated than
other animals, 28; migrations of,
47; wide distribution of, 48; causes
of the nakedness of, 57; supposed
physical inferiority of, 64; a mem-
ber of the Catarrhine group, 155 ;
early progenitors of, 160; transition
from ape indefinite, 180; numerical
proportions of the sexes in, 215;
difference between the sexes, 223 ;
proportion of sexes amongst the
illegitimate, 244; different com-
plexion of male and temale negroes,
556; secondary sexual characters of,
556; primeval condition of, 594.

Mandans, correlation of colour and
texture of hair in the, 197,

Mandible, left, enlarged in the male
of Zaphroderes distortus, 276.

Mandibles, use of the, in Aumophila,
275; large, of Corydalis cornutus,
275; large, of male Lu.anus ela-
phus, 275,

Mandrill, number of caudal vertebre
in the, 58; colours of the male,
538, 541, 550.

Mantegazza, Prof., on last molar
teeth of man, 20; bright colours
in male animals, 224; on the orna-
ments of savages 573 et seq.; cn
the beardlessness of the New Zea-
landers, 581; on the exaggeration of
natural characters by man, 582.

Mantell, W., on the engrossment of
pretty girls by the New Zealand
chiefs, 595.

Mantis, pugnacity of species of, 289.

Maories, mortality of, 184; infanti-
cide and proportion of sexes, 256 ;
distaste for hairiness amongst men,
581.

Marcus Aurelius, on the origin of the
moral sense, 98; on the influence
of habitual thoughts, 123.

Mareca penelope, 414.

Marks, retained throughout groups
of birds, 427,

Marriage, restraints upon, among sa-
vages, 46; influence of, upon morals,
1193. influence of, on mortality,
139; development of, 590.

Marriages, early, 138, 139; com-
maunal, 587, 589.

Marshall, Dr. W., protuberances on
birds’ heads, 235, 383; on the
moulting of birds, 393 ; advantage
to older birds of paradise, 485.

, Col., interbreeding amongst
Todas, 189; infanticide and pro-
portion of sexes with Todas, 235;
choice of husbands amongst Todas,
593.

—, Mr., on the brain of a Bush-
woman, 167.

Marsupials, 157; development of the
nictitating membrane in, 17; uterus
of, 39; possession of nipples by,
162; their origin from Monotre-
mata, 165; abdominal sacks of,
208; relative size of the sexes ut,
515 3 colours of, 533.

Marsupium, rudimentary, in male
marsupials, 161,

Martin, W. C. L., on alarm manifested
by an orang at the sight of a turtle,
72; on the hair in Hylobates, 152 ;
on a female American deer, 514;
on the voice of Hylobates agiis,
527 ; on Semnopithecus nemeus, 552.

.on the beards of the inhabitants
of St. Kilda, 560.

Martins deserting their young, 108.

, C., on death caused by inflam-
mation vf the vermiform appen-
dage, 21.

Mastoid processes in man and apes,_52.

Maudsley, Dr., on the influence of the
sense of smell in man, 18; oa
idiots smelling their food, 36; un
Laura Bridgman, 88; on the de-
velopment of the vocal organs, 89 ;
moral sense failing in incipient
madness, 124; change of mental
faculties at puberty in man, 565.

Mayers, W. F., on the domestication
of the goldfish in China, 343.

Mayhew, E., on the affection between
individuals of different sexes in the
dog, 523. .

660

MAYNARD,

INDEX.

MOGGRIDGE,

Maynard, C. J, on the sexes of Chry-
semys picta, 351.
Meckel, on correlated variation of the
muscles of the arm and leg, 44.
Medicines, effect produced by, the
same in man and in monkeys, 7.
Meduse, bright colours of some, 260.
Megalithic structures, prevalence of,
179.

Megapicus validus, sexual difference
of colour in, 458.

Megasoma, large size of males of,
279.

Meigs, Dr. A., on variation in the
skulls of the natives of America,
26.

Meinecke, on the numerical propor-.

tion of the sexes
250.

Melanesians, decrease of, 185.
Meldola, Mr., colours and marriage
dight of Colias and Pieris, 319.
Meliphagide, Australian, nidification

of, 454,

Melita, secondary sexual characters
of, 268.

Meloé, difference of colour in the
sexes of a species of, 294.

Memory, manifestations of, in ani-
mals, 74. |

Memnon, young, 168.

Mental characters, difference of, in
different races of men, 167.

— faculties, diversity of, in the
same race of men, 26; inheritance
of, 27; variation of, in the same
species, 27, 66; similarity of the
in different races of man, 178; of
birds, 410.

powers, difference of, in the
two sexes in man, 563.

Menura Alberti, 406 ; song of, 371.

—— superba, 406 ; long tails of both
sexes of, 451.

Merjanser, trachea of the male,
374,

—- serrator, male plumage of, 393.

Mergus cucullatus, speculum of, 236.

-— merganser, young of, 467.

Metallura, splendid tail-feathers of,
443.

Methova ichneumonides, large male of,
279.

Meves, M., on the drumming of the
snipe, 377.

in buttertlies,

Mexicans, civilisation of the. not
foreign, 145.

Meyer, on a convoluted body at the
extremity of the tail in a Mucacus
and a cat, 23.

—, Dr. A., on the copulation of
Phryganidz uf distinct species, 275.

, Prof. L., on development ot
helix of ear, 15, 16; men’s errs
more variable than women’s, 22-4;
antenne serving as ears, 280.

Migrations of man, effects of, 47.

Migratory instinct of birds, 105;
vanquishing the maternal, 107,
113.

Mill, J. S., on the origin of the moral
sense, 98; on the “ greatest hap-
piness principle,” 120; on the dif-
ference of the mental powers in
the sexes of man, 564.

Millipedes, 274.

Milne-Edwards, H., on the use of the
enlarged chele of the male Gelasi-
mus, 267.

Milvago lewcurus, sexes and y ~ung of,
479,

Mimicry, 323.

Minus polyglottus, 411.

Mind, difference of, in man and the
highest animals, 126; similarity
of the, in different races, 178.

Minuow, proportion of the sexes in
the, 249.

Mirror, larks attracted by, 415.

Mitchell, Dr., interbreeding in the
Hebrides, 189.

Mitford, selection of children in
Sparta, 29.

Mivart, St. George, on the reduction
of organs, 12; on the ears of the
Jemuroidea, 15; on variability of
the muscles in lemuroidea, 41, 483;
on the caudal vertebra of monkeys,
58; on the classification of the
primates, 153; on the orang and
on man, 1543 on differences in the
lemuroidea, 155; on the crest ot
the male newt, 348.

Mobius, Prof., on reasoning powers
in a pike, 75.

Mocking-thrush, partial migration of,
411; young of the, 487,

Modifications, unserviceable, 62.

Moggridge, J. T., on habits of spiders
69; on habits of ants, 147.

MOLES.

INDEX.

661

MOTACILLE,

Moies, numerical proportion of the
sexes in, 247; battles of male, 500.

Mollienesia petenensis, sexual ditfer-
ence in, 337.

Mollusca, beautiful colours and shapes
of, 263; absence of secondary
sexual characters in the, 262,

Molluscoida, 159, 262.

Monacanthus scopas and M. Peronii,
331.

Mongolians, perfection of the senses
in, 34,

Monkey, protecting his keeper from
a baboon, 103, 110; bonnet-, 151;
rhesus-, sexual difference in colour
of the, 539, 550; moustache-,
colours of the, 537.

Monkeys, liability of, to the same
diseases as man, 7; male, recog-
nition of women by, 8; diversity
of the mental faculties in, 27;
breaking hard fruits with stones,
50; hands of the, 50, 51; basal
caudal vertebre of, imbedded in the
body, 59; revenge taken by, 69;
maternal affection in, 70; varia-
bility of the faculty of attention
in, 74; American, manifestation of
yeason in, 77: using stones and
aticks, 81; imitative faculties of,
87; signal-cries of, 87; mutual
kindnesses of, 101; sentinels posted
by, 101; human characters of,
150; American, direction of the
hair on the arms of some, 151;
gradation of species of, 175; beards
of, 531; ornamental characters of,
549; analogy of sexual differences
of, with those of man, 558; dif-
ferent degrees of difference in the
sexes of, 561; expression of emo-
tions by, 572; generally mono-
gamous habits of, 590; polygamous
habits of some, 590; naked surfaces
of, 600.

aJonogamy, not primitive, 144.

Monogenists, 176. ‘

Mononychus pseudacori, stridulation
ot, 305,

Monotremata, 157; development of
the nicitating membrane in, 17;
lactiferous glands of, 162; connect-
ing mammals with reptiles, 165.

Monstrosities, analogous, in man and
lower animals, JU; crused by arrest

of development, 35; correlation of,
44; transmission of, 173.

Montagu, G., on the habits of the
black and red grouse, 219; on the
pugnacity of the ruff, 3613; on the
singing of birds, 368; on the
double moult of the male pintail,
393.

Monteiro, Mr., on Bucorax abyssi-
nicus, 383.

Montes de Oca, M., on the pugnacity
of male Humming irds, 36.

Monticola cyanea, 456.

Monuments, as_ traces
tribes, 181.

Moose, battles of, 501; horns of the,
an incumbrance, 515,

Moral and instinctive impulses, alli.
ance of, 111.

faculties, their influence on
natural selection in man, 127.

— rules, distinction between the
higher and lower, 122.

sense, so-called, derived from

the social instincts, 120, 121; origin

of the, 124.

tendencies, inheritance of, 124.

Morality, supposed to be founded in
selfishness, 120 ; test of, the general
welfare of the community, 121
gradual rise of, 125; influence of a
high standard of, 132.

Morgan, L. H., on the beaver, 67; on
the reasoniug powers of the beaver,
75; on the forcible capture of
wives, 144; on the castoreum of
the beaver, 529; marriage unknown
in primeval times, 588; on poly
andry, 593.

Morley. J., on the appreciation of
praise and fear of blame, 146.

Morris, F. O., on hawks feeding an
orphan nestling, 409,

Morse, Dr., colours of mollusea, 264.

Morselli, E., division of the malar
bone, 39.

Mortality, comparative, of females
and males, 216, 243,

Morton, on the number of species of
man, 174, aa

Moschkau, Dr. A., on » speaking
starling, 85.

Moschus moschiferus, odoriferous or
gans of, 529,

Motacille, lndian, young of, 458.

of extinct

-662

MOTHS.

INDEX.

MusiL,

Moths, 913; absence of mouth ia
some males, 208; apterous female,
208; male, prehensile use of the
tarsi by, 209; male, attracted by

. females, 252; coloration of, 315;
sexual differences of colour in, 31€.

Motmot, inheritance of mutilation of
tail feathers, 60, 603; racket-
shaped feathers in the tail of a,
384.

Moult, double, 463; double annual,
in birds, 390.

Moulting of birds, 484.

Moults, partial, 392, .

Mouse, song of, 568.

Moustache-monkey, colours of the,
537, 552.

Moustaches, in monkeys, 160.

Mud-turtle, long claws of the male,
350.

Mulattces, persistent fertility of,
171; immunity of, from yellow
fever, 195,

Mule, sterility and strong vitality of
the, 171.

Mules, rational, 78.

Muller, Ferd., on the Mexicans and
Peruvians, 145.

-, Fritz, on astomatous males of
Tanais, 208; on the disappearance
of spots and stripes in adult mam-
mals, 5473 on the proportions of
the sexes in some Crustacea, 255;
on secondary sexual characters in
various Crustaceans, 265 et seq.;
musical contest between male Ci-
cade, 282; mode of holding wings
in Castnia, 315 ; on birds shewing a
preference for certain colours, 317 ;
on the sexual maturity of young
amphipod Crustacea, 485,

—, Hermann, emergence of bees
trom pupa, 214; pollen-gathering
of bees, 228; proportion of sexes
in bees, 254; courting of Hristalis,
280; colour and sexual selection
with bees, 292.

, J., on the nictitating membrane
and semilunar fold, 17.

=——, Maz, on the origin of language,
87; language implies power of
general conception, 88; struggle
for life among the words, &c., of
sanguages, 91.

w——-, S., on the banteng, 536; on

the colours of Semnop:thecus chry-
somelas, 537.

Muntjac-deer, weapons of the, 514.

Murie, J., on the reduction of organs,
12; on the ears of the Lemuroidea,
15; on variability of the muscles
in the Lemuroidea, 41, 48; basal
caudal vertebra of Maca-us brun-
neus imbedded in the body, 59;
on the manner of sitting in short-
tailed apes, 59; on ditferences in
the Lemuroidea, .155; on the
throat-pouch of the male bustard,
373; on the mane of Utaria jubatu,
521; on the sub-orbital pits of
Ruminants, 529; on the colours of
the sexes in Otaria nigrescens, 535,

Murray, A., on the Pediculi of dit:
ferent races of men, 169.

T. A, on the fertility of Auctra-
lian women with white men, 170.

Mus conin ja, 80.

minutus, sexual difference in the
colour of, 534.

Musca vomitoria, 54.

Muscicapa grisola, 455.

luctuosa, 455.

ruticila, breeding in immature
plumage, 484.

Muscle, ischio-pubic, 41.

Muscles, rudimentary, occurrence of,
in man, 12; variability of the, 26;
effects of use and disuse upon, 32;
animal-like abnormalities of, in
man, 41; correlated variation ot,
in the arm and leg, 44; variability
of, in the hands and feet, 48; of
the jaws, influence of, on the phy-
siognomy of the Apes, 54; habitual
spasms of, causing modifications of
the facial bones, 55; of the early
progenitors of man, 160; greater
variability of the, in men than in
women, 223.

Musculus sternalis, Prof. Turner on
the, 13.

Music, 178 ;, of birds, 368; discord-
ant, love of savages for, 380; rea-
son of power of perception of notes
in animals, 568; power of distin-
guishing notes, 569; its connection
with primeval speech, 570; differ-
ent appreciation of, by differen!
peoples, 570; origin of, 569, 573
effects of, 571.

MUSICAL.

INDEX.

NEW ZEALAND.

663

Musical cadences, perception of, by
animals, 569; powers of man, 566
et seq.

Musk-deer, canine teeth of male, 502,
513, 514; male, odiferous organs
of the, 529; winter change of the,
542,

Musk-duck, Australian, 359; large
size of male, 362; of Guiana, pug-
aacity of the male, 362,

Musk-ox, horns of, 505.

Musk-rat, protective resemblance of
the, to a clod of earth, 542.

Musophage, colours and nidification
of the, 455; both sexes of, equally
brilliant, 460.

Mussels opened by monkeys, 50.

Mustela, winter change of two species
of, 542,

Musters, Capt., on Rhea Darwinii,
479; marriages amongst Patago-
nians, 598.

Mutilations, healing of, 8; inheri-
tance of, 60.

Mutilla curopea, stridulation of, 292.

Mutillide, absence of ocelli in female,
275.

Mycetes caraya, polygamous, 217;
vocal organs of, 527; beard of, 531;
sexual differences of colour in,
537 3 voice of, 567.

seniculus, sexual differences of
colour in, 537.

Myriapoda, 274.

N.

Nageli, on the influence of natural
selection on plants, 61; on the
gradation of species of plants, 175.

Nails, coloured yellow or purple in
part of Africa, 574,

Narwhal, tusks of the, 502, 507.

Nasal cavities, large size of, in Ame-
rican aborigines, 34,

Nascent organs, 12.

Nathusius, H. von, on the improved
breeds of pigs, 177; male domes-
ticated animals more variable than
females, 223; horns of castrated
sheep, 506; on the breeding of
domestic animals, 596.

Natural selection, its effects on the
early progenitors of man, 47; in-
fluence of on man, 60, 62; limita-

tion of the principle, 613 influence
, of, on social animals, 62; Mr, Wal-
lace on the limitation of, by the
influence of the mental faculties in
man, 127 ; influence of, in the pro-

"gress of the United States, 142; in

relation to sex, 259.

Natural and sexual selection con-
trasted, 226.

Naulette, jaw from, large size of the
canines in, 40.

Neanderthal skull, capacity of the,
55.

Neck, proportion of, in soldiers and
sailors, 32.

Necrophorus, stridulation of, 302,
304.

Nectarinia, young of, 468.

Nectarinie, moulting of the, 392;
nidification of, 454,

Negro, resemblance of a, to Europeans,
in mental characters, 178.

Negro-women, their kindness to Mungo
Park, 118.

Negroes, Caucasian features in, 167 ;
character of, 168; lice of, 170; ter-
tility of, when crossed with othcr
races, 171; blackness of, 170, 173;
variability of, 174,175; immunity
of, from yellow fever,193; difference
of, from Americans, 197 ; disfigure-
ments of the, 541; colour of new-
born children of, 557; comparative
beardlessness of, 560; readily be-
come musicians, 570; appreciation
of beauty of their women by, 577,
579; idea of beauty among, 582;
compression of the nose by some,
583.

Nemertians, colours of, 264.

Neolithic period, 145. ,

Neomorpha, sexual difference of the
beak in, 359.

Nephila, size of male, 273.

Nests, made by fishes, 345; decora-
tion of, by Humming-birds, 413.
Neumeister, on a change of colour in
pigeons after several moultings,

238.

Neuration, difference of. in the two
sexes of some butterflies and hy-
menoptera, 277.

Neuroptera, 254, 290.

Neurotiemis, dimorphism in, 291.

New Zealand, expectation by the

b64

NEWTON,

INDEX.

ONT IS.

natives of, of their extinction, 191;
practice of tattooing in, 576; aver-
sion of natives cf, to hairs on the
face; 5815 pretty girls engrossed
by the chiefs in, 595.

Newton, A., on the throat-pouch of
the male bustard, 373; on the dif-
ference between the females of two
species of Oxynotus, 4703 on the
habits of the Phalarope, dotterel,
and godwit, 477.

Newts, 348,

Nicholson, Dr., on the non-immunity
of dark Europeans from yellow
fever, 195.

Nictitating membrane, 17, 161.

Nidification, of fishes, 344; relation
of, to colour, 453, 456; of British
birds, 454,

Night-heron, cries of the, 368.

Nightingale, arrival of the male

before the female, 212; cbject of

the song of the, 368.

Nightingales, new mates found by
408.

Nightjar, selection of a mate by the
female, 416; Australian, sexes of
479 ; coloration of the, 491.

Nightjars, noise made by some male,
with their wings, 376; elongated
feathers in, 384, 403.

Nilghau, sexual differences of colour
in the, 535.

Nilsson, Prof., on the resemblance of
stone arrow-heads from various
places, 179; on the development of
the horns in the reindeer, 234,

Nipples, absence of, in Monotremata,
162.

Nitsche, Dr., ear of foetal orang, 17.

Nitzsch, C. L., on the down of birds,
390.

Noctuxz, brightly-coloured beneath,
315.

Noctuide, coloration of, 313.

Nomadic habits, unfavourable to
human progress, 133.

Nordmann, A., on Tetrao urogalloides,
405.

Norfolk island, half-breeds on. 190.

Norway, numerical proportion of male
and female births in, 243.

Nose, resemblance of, in man and the
apes, 153; piercing and ornamen-
tation of the, 575; very flat, aot

admired in negroes, 582; flattening
of the, 583.

Nott and Gliddon, on the features of
Rameses IL, 168; on the features
of Amunoph III., 168; on skulis
from Brazilian caves, 168; on the
immunity of negroes and mulattoes
from yellow fever, 193; on the de-
formation of the skull among Ame-
rican tribes, 583,

Novara, voyage of the, suicide in New
Zealand, 117.

Nudibranch Mollusca, bright colours
of, 264.

Numerals, Roman, 144; origin of,
264,

Nunemaya, natives of, bearded, 349,
560.

Nut-hatch of Japan, intelligence of,
410.

0.

Obedience, value of, 130.

Observation, powers of, possessed by
birds, 411.

Occupations, sometimes a cause of
diminished stature, 31; effect of,
upon the proportions of the body,
31. ;

Ocelli, absence of, in female Mutil-
lide, 274,

of birds, formation and vari-
ability of the, 427.

Ocelot, sexual differences in the colour-
ing of the, 534,

Ocyphaps luphotes, 402.

Odonata, 254.

Odonestis potatoria, sexual difference
of colour in, 316.

Odour, correlation of, with colour of
skin, 197; emitted by snakes in
the breeding-seascn, 352; of main-
mals, 528.

Gcanthus nivalis, difference of colour
in the sexes of, 289.

pellucidus, 289.

Ogle, Dr. W., relation between colour
and power of smell, 18.

Oidemia, 491.

Olivier, on sounds
Pimelia striata, 306.

Omaloplia brunnea, stvidulation of,
303.

Onitis furcifer, processes of anteriot

produced by

ONTHOLHAGUS.

INDEX.

OWEN.

665

femora of the male, and on the
head and thorax of the female,
297.

Onthophagus, 295.

—— rangifer, sexual differences of,
296; variation in the horns of the
male, 297,

Ophidia, sexual differences of, 351.

Ophidium, 347.

Opossum, wide range of, in America,
169.

Optic nerve, atrophy of the, caused
oy destruction of the eye, 32,

Grang-Outan, 561; Bischoff on the
agreement of the brain of the,
with that of man, 6; adult age
of the, 8; ears of the, 14; ver-
miform appendage of, 21; hands
of the, 50; absence of mastoid pro-
cesses in the, 53; platforms built
by the, 66; alar med at the sight of
a turtle, 72; using a stick as a
lever, 81; using missiles, 81; using
the leaves of the Pandanus as a
night covering, 82; direction of
the hair on the arms of the, 151;
its ahérrant characters, 1543; sup-
posed evolution of the, 177; voice
of the, 527; monogamous habits
of the, 590; male, beard of the,
531.

Oranges, treatment of, by monkeys,
50.

Crange-tip butterfly, 308, 312, 313.

Orciestia Darwinit, dimorphism of
males of, 268.

Tucuratinga, limbs of, 267, 271.

Ordeal, trial by, 96.

reas canna, colours of, 535,

Derbianus, colours of, 535, 543,

Organs, prehensile, 209 ; utilised for
new purposes, 571.

Organic scale, von Baer’s definition of
progress in, 164,

Orioles, nidification of, 453.

Oriolus, sp2cies of, breeding in im-
mature plumage, 484.

_—- melanocephalus, coloration of the
sexes in, 460.

Ornamerts. prevalence of similar,
179; of male birds, 367; fondness
of savages for, 574.

Ornamental characters, equal trans-
mission of, to both sexes, in mam-
mals, 541; of monkeys, 549.

Ornithoptera cresus, 250.

Ornithorhynchus, 156; reptilian ten-
dency of, 159; spur of the male,
502.

Orocetes erythrogastra, young of, 487.

Orrony, Grotto of, 22.

Orsodacna atra, difference of colour iu
the sexes of, 294,

Orthoptera, 282; metamorphosis of,
237; stridulating apparatus of,
283, 288; colours of, 289; rudi-
mentar y stridulating organs in
female, 288; stridulation of the,
and Homoptera, discussed, 288.

Ortygornis gularis, pugnacity of the
male, 36

Oryctes, stridulation of, 303; sexual
differences in the stridulant organs
of, 305.

Oryx leucoryx, use of the horns of,
509, 518

Osphranter rufus, sexual difference in
the colour of, 533.

Ostrich, African, sexes and incuba-
tion of the, 478.

Ostriches, stripes of young, 464.

Otaria jubata, mane of the male.
521.

nigrescens, difference in the
coloration of the sexes of, 534.

Otis bengalensis, love-antics of the
male, 380.

tarda, throat-pouch of the male,
373; polygamous, 219.

Ouzel, ring-, colours and nidification
of the, 455,

» water-, colours and nidifica-
tion of the, 455.

Ovibos moschatus, horns of, 505.

Ovipositor of insects, 208.

Ovis cycloceros, mode of fighting of,
508, 513,

Ovule of man, 9.

Owen, Prof., on the Corpora Wolt-
fiana, 11; on the great toe in man,
11; on the nictitating membrane
and semilunar fold, 17; on the
development of the posterior mo-
lars-in different races of man, 20;
on the length of the cecum in the
Koala, 20; on the coceygeal ver-
tebre, 23; on rudimentary struc-
tures belonging to the reproductive
system, 24; on abnormal condi-
tions of the human uterus, 38

OWwLs,

566

INDEX.

PARAGUAY,

on the number of digits in the
Ichthyopterygia, 37; on the canine
teeth in man, 40; on the walking
of the chimpanzee and orang, 50;
on the mastoid processes i the
higner apes, 53; on the hairiness
of elephants in elevated districts,
57; on the caudal vertebra of
monkeys, 58; classification of mam-
malia, 148; on the hair in mon-
keys, 152; on the piscine affinities
of the Ichthyosaurians, 159; on
pologamy and monogamy among
the antelopes, 217; on the horns
of Antilocapra americana, 234; on
the musky odour of crocodiles
during the breeding season, 351;
on the scent-glands of snakes, 352 ;
on the Dugong, Cachalot and Or-
nithorhynchus, 502; on the antlers
of the red deer, 510; on the den-
tition of the Camelidz, 514; on the
horns of the Irish elk, 515; on
the voice in the giraffe, porcupine,
and stag, 526; on the laryngeal
sac of the gorilla and orang, 527;
on the odoriferous glands of mam-
mals, 528, 529; on the effects of
emasculation on the vocal organs of
men, 5663; on the voice of Hylo-
bates agilis, 567; on American
monogamous monkeys, 567.

Owls, white, new mates found by,
408.

Oxynotus, difference of the females of
two species of, 470.

P.

Pachydermata, 218.

Paehytylus migratorius, 283.

Paget, on the abnormal development
of hairs in man, 19; on the thick-
ness of the skin on the soles of the
feet of infants, 33.

Painting, pleasure of savages in, 178.

Palemon, chele of a species of, 267.

Paleornis, sexual differences cf colour
in, 494.

——— javanicus, colour of beak of,
461.

—— rosa, young of. 467.

Palamedea cornuta, spurs on the
wings, 364.

Paleolithic period, 145.

Palestine, habits of the chaffinch in,
248,

Pallas, on the perfection of the senses
in the Mongolians, 34; on the
want of connexion between clis
mate and the colour of the skin,
192; on the polygamous habits of
Antilope Saiga, 217; on the lighter
colour .of horses and cattle in
winter in Siberia, 229; on the
tusks of the musk-deer, 513, 514;
on the odoriferous glands of mam-
mals, 529; on the odoriferous
glands of the musk-deer, 530; on
winter changes of colour in mam-
mals, 542 ;-on the ideal of female
beauty in North China, 578.

Palmaris accessorius, muscle variations
of the, 27,

Pampas, horses of the, 181.

Pangenesis, hypothesis of, 228, 231.

Panniculus carnosus, 13.

Pansch, on the brain of a foetal Cebus
apella, 205.

Papilio, proportion of the sexes in
North American species of, 250;
sexual ditterences of colouring in
species of, 309; coloration of the
wings in species of, 312.

ascanius, 309,

Sesosir’s and Childrene, varia-

bility of, 319.

Turnus, 250.

Papilionide, variability in the, 319.

Papuans, line of separation between
the, and the Malays, 169; beards
of the, 560; hair of, 575.

and Malays, contrast in charac
ters of, 168.

Paradise, Birds of, 405, 462 ; supposed
by Lesson to be polygamous, 219;
rattling of their quills by, 375;
yacket-shaped feathers in, 38+;
sexual differences in colour of, 385 ;
decomposed feathers in, 385, 403;
display of plumage by the male,
395.

Paradisea apoda, barbless feathers in
the tail of, 385; plumage of, 385;
and P, Pap > 385 3 divergence
of the females of, 470; increase of
beauty with age, 485.

Paraguay, Indians of, eradication of
eyebrows and eyelashes by, 580,

PARAKEET.

INDEX.

PERCH,

667

Parakeet, Australian, variation in the
colour of the thighs cf a male,
423.

Parallelism of development of species
and languages, 90.

Parasites on man and animals, 7, 8;
as evidence of specific identity or
distinctness, 169 ; immunity from,
correlated with colour, 193.

Parental feeling in earwigs, star-
fishes, and spiders, 106; affection,
partly a result of natural selection,
105.

Parents, age of, influence upon sex of
offspring, 245.

Parinz, sexual difference of colour in,
458.

Park, Mungo, negro-women teaching
their children to love the truth,
118; his treatment by the negro-
women, 118, 562; on negro opinions
of the appearance of white men,
579,

’arker, Mr., no bird or reptile in line
of mammalian descent, 158.

Parrot, racket-shaped feathers in the
tail of a, 384; instance of benevo-
lence in a, 411.

Parrots, change of colour in, 60;
imitative faculties of, 73; living
in triplets, 409; affection of, 410;
colours and nidification of the, 455,
457, 458; immature plumage of
the, 467; colours of, 489; sexual
differences of colour in, 494; musi-
cal powers of, 570.

Parthenogenesis in the Tenthredinz,
254; in Cynipide, 254; in Crusta-
vea, 255.

Partridge, monogamous, 219 ; propor-
tion of the sexes in the, 248; fe-
male, 471.

-dances,” 380, 405.

Partridges, living in triplets, 409 ;
spring coveys of male, 409; distin-
guishing persons, 412,

Parus cxruleus. 458.

Passer, sexcs and young of, 483.

brachydactylus, 483.

— domesticus, 455, 483.

-— montanus, 455, 483.

Patagonians, self-sacrifice by, 112;
marriages of, 598.

Patterson, Mr., on the Agrionida,
290.

Patteson, Bishop, decrease of Melane
sians, 185.

Paulistas of Brazil, 173.

Pavo cristatus, 236, 430.

muticus, 236, 430; possession of

spurs by the female, 364, 450,

nigripennis, 419.

Payaguas Indians, thin legs and thick
arms of the, 32.

Payan, Mr., on the proportion of the
sexes in sheep, 246.

Peacock, polygamous, 219; sexual
characters of, 236; pugnacity of
the, 364; rattling of the quills by,
875; elongated tail-coverts of the,
884, 402; love of display of the,
394,431; ocellated spotsof the, 430;
inconvenience of long tail of the, to
the female, 444, 451, 452; continued
increase of beauty of the, 485.

-butterfly, 312.

Peafowl, preference of females for a
particular male, 418 ; first advances
made by the female, 419.

Pediculi of domestic animals and man,
169,

Pedigree of man, 165.

Pedionomus torquatus, sexes of, 473.

Peel, J., on horned sheep, 505,

Peewit, wing-tubercles of the male,
366.

Pelagic animals, transparency of, 261.

Pelecanus erythrorhynchus, horny crest.
on the beak of the male, during the
breeding season, 390.

——- onocrotalus, spring plumage of,
393,

Peleld, an African ornament, 576.

Pelican, blind, fed by his companions,
102; young, guided by old birds,
102; pugnacity of the male, 362.

Pelicans, fishing in concert, 101.

Pelobius Hermanni, stvidulation of,
303, 304.

Pelvis, alteration of, to suit the erect
attitude of man, 58; differences of
the, in the sexes in man, 557.

Penelope nigra, sound produced by the
male, 377.

Pennant, on the battles of seals, 500;
on the bladder-nose seal, 528.

Penthe, antennal cushions of the male,
276.

Perch, brightness of male, during
breeding season, 540,

668

PEREGRINE,

INDEX.

PIGKONS,

Peregrine falcon, new mate found by,
408.

Period of variability, relation of, to
sexual selection, 240.

Periodicity, vital, Dr. Laycock, on, 8.

Periods, lunar, followed by functions
in man and animals, 8, 164.

—— of life, inheritance at corre-
sponding, 228, 232,

Perisoreus canadensis, young of, 481.

Peritrichia, difference of colour in the
sexes of a species of, 294.

Periwinkle, 262.

Pernis cristata, 424.

Perrier, M., on sexual selection, 210;
on bees, 292.

Perseverance, a characteristic of man,
564,

Persians, said to be improved by 1n-
termixture with Georgians and Cir-
cassians, 586.

Personnat, M., on Bombyx Yamamai,
251,

Peruvians, civilisation of the, not
foreign, 145,

Petrels, colours of, 493.

Petrocincla cyanea, young of, 487.

Petrocossyphus, 461,

Petronia, 483.

Pfeiffer Ida, on Javan ideas of beauty,
580.

Phacocherus a@thiopicus, tusks and
pais of, 519.

Phalanger, Vulpine, black varieties of
the, 539.

Pialaropus fulicarius, 476.

—— hyperboreus, 476.

Phanaus, 298.

carnifex, variation of the horns

of the male, 297.

Jaunus, sexual differences of,

296.

lancifer, 295.

Phaseolarctus cinereus, taste for rum
and tobacco, 7.

Phasgonura viridissima, styidulation
of, 284, 285.

Phasianus Seemmerringti, 446.

——— versicolor, 396.

Wallichii, 400, 472.

Pheasant, polygamous, 219 ; and black
grouse, hybrids of, 414; production
of hybrids with the common fowl,
420 immature plumage of the,
466.

Pheasant, Amherst, display of, 396.

, Argus, 334, 462; display ef

plumage by the male, 398; ocel-

lated spots of the 428,434; grada-

tion of characters in the, 434.

» Blood-, 364.

——, Cheer, 400, 472.

, Eared, 235, 400, 472; length

of the tail in the, 452; sexes alike

in the, 460.

» Golden, display of plumage

by the male, 396; age of mature

plumage in the, 483 ; sex of young,
ascertained by pulling out head-

feathers, 484,

, Kalij, drumming of the male,

375,

» Reeve’s, length of the tail in,

452.

, Silver, triumphant male, de-
posed on account of spoiled plu-
mage, 419; sexual colurativn of the,
492,

——,, Semmerring’s, 445, 452.

——, Tragopan, 3883; display of
plumage by the male, 397 ; mark-
ings of the sexes of the, 428.

Pheasants, period of acquisition of male
characters in the family of the,
235; proportion of sexes in chicks
of, 247; length of the tail in, 445,
451, 452,

Philters, worn by women, 577.

Phoca grentandica, sexual diflerence
in the coloration of, 535.

Phenicura ruticilla, 408.

Phosphorescence of insects, 277.

Phryganide, copulation of distinct
species of, 275,

Phryniscus nigricans, 349,

Physical inferiority, supposed, of man,
64.

Pickering, on the number of species
of man, 174.

Picton, J, A.,on the soul of man, 613.

Picus auratus, 362,

major, 402.

Pieris, 312 ,319.

Pigeon, female, deserting a weakened
mate, 214; carrier, late develop-
ment of the wattle in, 238:
pouter, late developreent of the
crop in, 238; domestic, breeds and
sub-breeds of, 460.

Pigeons, nestling, fed by the secretion

PIGS.

INDEX.

POLYGAMY,

669

of the crop of both parents, 163;
changes of plumage in, 229; trans-
mission of sexual peculiarities in,
230; Belgian, with black-streaked
males, 231, 238, 446; changing
colour after several moultings, 238 ;
numerical proportion of the sexes
in, 247 ; cooing of, 374; variations
in plumage .of, 385; display of
plumage. by male, 402; local me-
mory of, 411; antipathy of female,
to certain males, 418; pairing of,
418; profligate male and female,
418; wing-bars and tail-feathers
ot, 427; suppositious breed of, 445 ;
pouter and carrier, peculiarities of,
predominant in males, 447; nidi-
fication of, 453; Australian, 458;
immature plumage of the, 467.

Pigs, origin of the improved breeds
of, 177; numerical proportion of
the sexes in, 247; stripes of young,
464, 546; tusks of miocene, 521;
sexual preference shewn by, 525,

Pile, American, brilliant colours of
the male, during the. breeding
season, 340,

, Yeasoning powers of, 75; male,
devoured by females, 249.

Pike, L. O., on the psychical elements
ot religion, 95,

Pimelia striata, sounds produced by
the female, 306.

Pinel, hairiness in idiots, 36.

Pintail, drake, plumage of, 393;
pairing with a wild duck, 415.

— Duck, pairing with a wigeon,
414,

Pipe-fish, filamentous, 344; mar-
supial receptacles of the male, 346,

Pipits, moulting of the, 392,

Pipra, modified secondary wing-
teathers of male, 378.

deliciosa, 378, 379.

Pirates stridulus, stridulation of, 281.

Pitcairn island, half-breeds on, 190,

Pithecia leucocephala, sexual differ-
ences of colour in, 537.

Satanas, beard of, 531, 532;
resemblance of, to a negro, 604.

Pits, suborbital, of Ruminants, 529,

Pittide, nidification ot, 453.

Placentata, 157.

Plagiostomous fishes, 331,

Plain-wan lerer, Australian, 473.

Planaria, bright colours of some,
260.

Plantain-eaters, colours and nidi-
fication of the, 455; both sexes of,
equally brilliant, 460. .

Plants, cultivated, more fertile than
wild, 45; Nageli, on natural selec-
tion in, 61; male flowers of, mature
before the female, 212; phenomena
of fertilisation in 222,

Platalea, 374; change of plumage in,
461,

Platyblemnus, 289.

Platycercus, young of, 481.

Platyphyltum concavuin, 283, 286.

Platyrrhine monkeys, 153.

Platysma myoides, 13.

Plecostomus, head-tentacles of the
males of a species of, 338,

barbatus, peculiar beard of the
male, 338,

Plectropterus gambensis, spurred wings
of, 364.

Ploceus, 370, 375, 405,

Plovers, wing-spurs of, 365; double
moult in, 392.

Plumage, changes of, inheritance of,
by fowls, 223; tendency to ana-
logous variation in, 385; display
of, by male birds, 394, 402; changes
of, in relation to season, 462; im-
mature, of birds, 464, 465; colour
of, in relation to protection, 489.

Plumes on the head in birds, differ-
ence of, in the sexes, 451.

Pneumora, structure of, 286.

Podica, sexual difference in the colow
of the irides of, 425,

Poeppig, on the contact of civilised
and savage races, 183.

Poison, avoidance of, by animals, 80

Poisonous fruits and herbs avoided by
animals, 66.

Poisons, immunity from, correlated
with colour, 193.

Polish fowls, origin of the crest in,
231.

Pollen and van Dam, on the cclours
of, Lemur macaco, 5387.

Polyandry, 593; in certain Cypri-
nidz, 249; among the blateride,
253.

Polydactylism in man, 37.

Polygamy, influence of, upon sexual
selection, 216; superinduced by

670 POLYGENISTS,

INDEX.

PUFF-BIRLS.

domestication, 220; supposed .a-
crease of temale births by, 245; in
the stickleback, 332.

Polygenists, 176,

Polynesia, prevalence cf infanticide
in, 592.

Polynesians, wide geographical range
of 29; difference of stature among
the, 31; crosses of, 173; variability
of, 174; heterogeneity of the, 192;
aversion of, to hairs on the face,
581.

/'olyplectron, number of spurs in, 3645
display of plumage by the male,
396; gradation of characters in,
431; female of, 471.

—— chinquis, 397, 432,

Hardwickit, 432.

-—— malaccense, 432, 433.

Napoleonis, 482, 433.

Polyzoa, 262.

/‘ontoporeia affinis, 266,

Porcupine, mute, except in the rut-
ting season, 526.

Pores, excretory, numerical relation
of, to the hairs in sheep, 198.

P rpite, bright colours of some, 260,

Vortax picta, dorsal crest and throat-
tuft of, 530; sexual differences of
colour in, 535, 543.

Portunus puber, pugnacity of, 269.

Potamocherus penicillatus, tusks and
facial knobs of the, 520,

Pouchet, G., the relation of instinct
to intelligence, 67; on the in-
stincts of ants, 147; on the caves
of Abou-Simbel, 168; on the im-
munity of negroes from yeliow
fever, 193; change of colour in
fishes, 344,

Pouter pigeon, late development of
the large crop in, 238.

Powell, Dr., on stridulation, 281.

Power, Dr., on the different colours
of the sexes in a species of Squilla,
271,

Dowys, Mr., on the habits of the
enatlinch in Corfu, 248.

Pre-eminence of man, 48

Preterence for males by female birds,
414, 420; shewn by mammals, in
pairing, 522.

Prehensile organs, 209.

Presbytis entellus, fighting of tne
male, 562.

Preyer, Dr., on function of shell of
ear, 14; on supernumerary mam-
mez in women, 37.

Prichard, on the difference of stature
among the Polynesians, 31; on the
connection between the breadth of
the skull in the Mongolians and the
perfection of their senses, 345; on
the capacity of British skulls of
different ages, 55; on the flattened
heads of the Colombian savages,
575; on Siamese notions of beauty,
578; on the beardlessness of the
Siamese, 581; on the deformation
of the head among American tribes
and the natives of Arakhan, 583.

Primary sexual organs, 207.

Primates, 149, 205 ; sexual differences
of colour in, 537.

Primogeniture, evils of, 135.

Prionidz, difference of the sexes im

- colour, 294.

Proctotretus multinaculatus, 358.

tenuis, sexnal difference in the
colour of, 358.

Profligacy, 137.

Progenitors, early, of man, 160.

Progress, not the norma) rule in hu-
man society, 133; elements of, 142,

Prong-horn antelope, horns of, 234,

Proportions, ditference ot, in distinct
races, 167,

Protective colouring in butterflies,
312; in lizards, 358; in birds, 473,
489; in mammals, 542,

nature of the dull colouring of

female Lepidoptera, 321, 322, 324.

resemblances in fishes, 344.

Protozoa, absence of secondary sexual
characters in, 260.

Pruner-Bey, on the occurrence of the
supra-condyloid foramen in the
humerus of man, 22; on the colour
of negro infants, 557.

Prussia, numerical proportion of male
and female births in, 243.

Psocus, proportions of the sexes in,
254.

Ptarmigan, monogamous, 219; sum-
mer and winter plumage of the,
390, 392; nuptial assemblages of,
406 ; triple moult of the, 462; pro-
tective coloration of, 473.

Puff-birds, colours and nidification of
the, 455.

PUGNACITY.

INDEX.

RAYS,

Pugnacity of fine-plumaged male
birds, 400.

Pnmas, stripes of young, 464.

Puppies learning from cats to clean
their faces, 73.

Pycnonotus hamorrhous, pugnacity of
the male, 360; display of under
tail coverts by the male, 402,

Pyranga estiva, male aiding in incu-
bation, 453.

Pyrodes, difference of the sexes in
colour, 294.

Q.

Quadrumana, hands of, 50; differences
between man and the, 1493; sexual
differences of colour in, 537; orna-
mental characters of, 549; analogy
of sexual differences of, with those
of man, 558; fighting of males for
the females, 562; monogamous
habits of, 590; beards of the, 602.

Quain, K., on the variation of the
muscles in man, 26.

Quatrefages, A. de, on the occur-
rence of a rudimentary tail in man,
223; on variability, 30; on the
moral sense as a distinction between
man and animals, 97 ; civilised men
stronger than savages, 136; on the
fertility of Australian women with
white men, 170; on the Paulistas
of Brazil, 173; on the evolution of
the breeds of cattle, 177; on the
Jews, 193; on the liability of
negroes to tropical fevers after
residence ina cold climate, 194;
on the difference between field-
and house-slaves, 196; on the in-
fluence of climate on colour, 196;
colours of annelids, 265; on the
Ainos, 560; on the women of
San Giuliano, 586.

Querquedula acuta, 414.

Quetelet, proportion of sexes in man,
343; relative size in man and
woman, 244,

Quichua Indians, 34; local variation
of colour in the, 196; no grey
hair among the, 559; hairlessness
of the, 561; long hair of the, 580.

Quiscalus major, 225; proportions of
the sexes of, in Florida and Hondu-
ras, 248.

Rabbit, white tail of the, 542.

Rabbits, domestic, elongation of the
skull in, 56; modification of the
skull, in by the lopping of the
ear, 565 danger-signals of, 100:
numerical proportion of the sexes
in, 247,

Races, distinctive characters of, 167,
168 ; or species of man, 168; crossed,
fertility or sterility of, 170; of
man, variability of the, 174; of
man, resemblance of, in mental
characters, 178; formation ot,
1813 of man, extinction of, 181;
effects of the crossing of, 192; of
man, formation of the, 192; of
man, children of the, 557; beard-
less, aversion of, to hairs on the
face, 580.

Raffles, Sir S., on the banteng, 536.

Rafts, use of, 48, 180.

Rage, manifested by animals, 69.

Raia batis, teeth of, 335.

cluvata, female spined on the

back, 3315 sexual difference in tha

teeth of, 334.

— maculata, teeth of, 335.

Rails, spur-winged, 364.

Ram, mode of fighting of the 508;
African, mane of an, 532; fat-
tailed, 532.

Rameses II., features of, 168.

Ramsay, Mr., on the Australiau
musk-duck, 359; on the regent-
bird, 413; on the incubation of
Menura superba, 451.

Rana esculenta, vocal sacs of, 350.

Rat, common, general dispersion of,
a consequence of superior cunning,
80; supplantation of the native,
in New Zealand, by the European
rat, 191; common, said to be puoly-
gamous, 218; numerical prupor-
tion of the sexes in, 247.

Rats, enticed by essential oils, 530.

Rationality of birds, 410.

Rattle-snakes, difference of the sexes
in the, 3513 rattles as a call, 353.

Raven, vocal organs of the 370;
stealing bright objects, 413; pied,
of the Feroe Islands, 424.

Rays, prehensile organs of male, 331,

672

RAZOR-BILL,

INDEX.

RICHARDSON.

Razor-bill, young of the, 486.

Reade, Winwood, suicide among
savages in Africa, 117; mulattoes
not prolific, 171; effect of castra-
tion of horned sheep, 506 ; on the
Guinea sheep, 235; on the occur-
rence of a mane in an African
ram, 533; on the negroes’ appre-
ciation of the beauty of their
women, 577; on the admiration of
negroes for a black skin, 579; on
the idea of beauty among negrocs,
582; on the Jollofs, 587; on the
marriage-customs of the negroes,
599.

Reason, in animals, 75.

Redstart, American, breeding in im-
mature plumage, 484.

Redstarts, new mates found by, 408.

Reduvida, stridulation of, 281.

Reed-bunting, head-feathers of the
male, 402 ; attacked by a bull-finch,
412,

Reefs, fishes frequenting, 343,

Reeks, H., retention of horns by
breeding deer, 503; cow rejected
by a bull, 525; destruction of pie-
bald rabbits by cats, 542.

Regeneration, partial, of lost parts in
man, 8.

Regent-bird, 413.

Reindeer, horns of the, 233; battles
of, 501; horns of the female, 503;
antlers of, with numerous points,
510; winter change of the, 542;
sexual preferences shewn by, 552.

Relationship, terms of, 590.

Religion, deficiency of, -among cer-
tain races, 93; psychical elements
of, 95.

Remorse, 114; deficiency of, among
savages, 131.

Rengger, on the diseases of Cebus
Azare, 7; on the diversity of the
mental faculties of monkeys, 27;
on the Payaguas Indians, 32; on
the inferiority of Europeans to
savages in their senses, 33; re-
venge taken by monkeys, 69; on
maternal affection in a Cebus, 70;
on the reasoning powers of Ameri-
can monkeys, 77; on the use of
stones by monkeys for cracking
hard nuts, 81; on the sounds ut-
tered by Cebus Azara, 84; on the

signal-cries of monkeys, 87; on the
polygamous habits of Mfycctes ca-
raya, 217; on the voice of the how-
ling monkeys, 527; on the odour
of Cervus campestris, 529; on the
beards of Mycetes caraya and
Pithecia Satanas, 531; on the
colours of Feliz mitis, 534; on the
colours of Cervus paludusus, 536 ;
on sexual differences of colour in
Mycetes, 537; on the colour of the
intant Guaranys, 558 ; on the early
maturity of the female of Cebus
aza' @, 558; on the beards of tne
Guaranys, 561; on the emotional
notes employed by monkeys, 572;
on American polygamous monkeys,
590.

Representative species, of birds, 468.

Reproduction, unity of phenomena
of, throughout the mammalia, 8;
period of, in birds, 484.

Reproductive system, rudimentary
structures in the, 23; accessory
parts of, 161.

Reptiles, 350.

and birds, alliance of, 165.

Resemblances. small, between man
and the apes, 150.

Retrievers, exercise of
faculties by, 78.

Revenge, manifested by animals, 69.

Reversion, 36; perhaps the cause of
some bad dispositions, 137.

Rhagium, ditference of colour in the
sexes of a species of, 294.

Rhamphastos carinatus, 492.

Rhea darwinit, 479.

Rhinoceros, nakedness of, 57; horns
of, 505 ; horns of, used defensively,
518; attacking white or grey
horses, 540.

Rhynchea, sexes and young of, 476.

australis, 476,

bengalensis, 476.

capensis, 477.

Rhythm, perception of, by animals,
569.

reasoning

Richard, M., on rudimentary muscles
in man, 12.

Richardson, Sir J., on the pairing of
Tetrao umbellus, 366; on Tetrao
urophasianus, 372; on the drums
ming of grouse, 376; on the dances
of Tetrao phasianellus, 381; op

RICHARDSON.

INDEX.

SAILORS,

673

assemblages of grouse, 405; on the
battles of male deer, 501; on the
reindeer, 503; on the horns of the
musk-ox, 505; on antlers of the
reindeer with numerous points,
510; on the moose, 515.

Richardson, on the Scotch deer-
hound, 516.

Richter, Jean Paul, on imagination, 74.

Riedel, on profligate female pigeons,
218 :

Riley, Mr., on mimicry in butterflies,
3243; birds’ disgust at taste of
certain caterpillars, 326.

Ring-ouzel, colours and nidification
of the, 455.

Ripa, Father, on the difficulty of dis-
tinguishing the races of the Chinese,
167.

Rivalry, in singing, between male
birds, 369.

River-hog, African, tusks and knobs
of the, 520.

Rivers, analogy of, to islands, 159.
Roach, brightness of male during
breeding-season, 340,
Robbery, of strangers,

honourable, 117.

Robertson, Mr., remarks on the de-
velopment of the horns in the roe-
buck and red-deer, 234.

Robin, pugnacity of the male, 360;
autumn song of the, 370; female
singing of the, 370; attacking
other birds with red in their plu-
mage, 412; young of the, 480.

Robinet, on the difference of size of
the male and female cocoons of the
silk-moth, 278.

Rodents, uterus in the, 38; absence
of secondary sexual characters in,
218; sexual differences in the
colours of, 534,

Roe, winter change of the, 542.

Rohlfs, Dr., Caucasian features in
negro, 167; fertility of mixed
races in Sahara, 171; colours of
birds in Sahara, 490 ; ideas of beauty
amongst the Bornuans, 582.

Rolle, F., on the origin of man, 3;
on a change in German families
settled in Georgia, 196.

Roller, harsh ery of, 371.

Romans, ancient, gladiatorial exhi-
bitions of the, 123.

44

considered

Ronjou, M. A., coinciderce of arrested
development with polydactylism

Rook, voice of the, 375.

Réssler, Dr., on the resemblance of
the lower surface of butte: flies to
the bark of trees, 311.

Rostrum, sexual difference in the
length of, in some weevils, 208.
Royer, Madlle. mammals giving

suck, 163.
Rudimentary organs, 11; origin of,

Rudiments, presence of, in languages,
90.

Rudolphi, on the want of connexion
between climate and the colour of
the skin, 192.

Ruff, supposed to be polygamous,
219; proportion of the sexes in
the, 248; pugnacity of the, 361;
double moult in, 390,392; duration
of dances of, 405 ; attraction of the,
to bright objects, 413.

Ruminants, male, disappearance of
canine teeth in, 53, 562; geneylly
polygamous, 217; suborbital pits
of, 529; sexual differences of colour
in, 535.

Rupicola crocea, display of plumage
by the male, 395.

Ruppell, on canine teeth in deer and
antelopes, 514,

Russia, numerical proportion of male
and female births in, 215, 243.

Ruticilla, 462.

Riitimeyer, Prof., on the physiogno-
my of the apes, 54; on the sexual
differences of monkeys, 561,

Rutlandshire, numerical proportion
of male and female births in, 242,

Sachs, Prof., on the behaviour of the
male and female elements in fertili-
sation, 222.

Sacrifices, human, 144.

Sagittal crest in male apes and
Australians, 558,

Sahara, fertility of mixed races in,
171; birds of the, 456; animal »-
habitants of the, 489.

Sailors, growth of, delayed by con-
ditions of lite, 31; long-sighted, 33

SAILORS.

674

INDEX,

SCHOMBURGE,

Sailors and soidiers, difference in the
proportions of, 32.

St. John, Mr., on the attachment of
mated birds, 410.

St. Kilda, beards of the inhabitants
of, 560.

Samo eriox, and S. umbla, colouring
of the male, during the breeding
yezson, 340,

ly aodon, 333.

salar, 333,

Salmon leaping out of fresh water,
107; male, ready to breed before
the female, 212; proportion of
the sexes in, 249; male, pugna-
city of the, 332; male, characters
of, during the breeding season, 332,
340; spawning of the, 344; breed-
ing of immature male, 485.

Salvin. O., inheritance of mutilated
feathers, 60, 384, 603; on the
Humming-birds, 219, 454; on the
numerical proportion of the sexes
in Humming-birds,, 248, 487; on
Chamepetes and Penelope, 377;
on Selasphorus platycercus, 378;
Pipra deliciosa, 378; on Chasmo-
rhynchus, 389.

Samoa Islands, beardlessness of the
natives of, 560, 581.

Sand-skipper, 270.

Sandwich Islands, variation in the
skulls of the natives of the, 26;
decrease of native population, 186 ;
population of, 257; superiority of
the nobles in the, 587.

Islanders, lice of, 170.

San-Giuliauo, women of, 586.

Santali, recent rapid increase of the,
45; Mr. Hunter on the, 192.

Saphirina, characters of the males of,
271,

Sarkidiornis melanonotus, characters
of the young, 465.

Sars, 0., on Pontoporeia affinis,
266.

Saturnia carpini, attraction of males
by the female, 252.

— /o, difference of coloration in the
sexes of, 316.

Saturniide, coloration of the, 314,
315.

Savage, Dr., on the fighting of the
male gorillas, 562; on the habits
of the gorilla, 591.

Savage and Wyman on the polyga-
mous habits of the gorilla, 217.
Savages, uniformity of, exaggerated,
28; long-sighted, 33; rate of in-
crease among, usually small, 45;
retention of the prehensile power
of the feet by, 52; imitative facul-
ties of, 87; 129; causes of low
morality of, 119; tribes of, sup-
planting one another, 128; im-
provements in the arts among,
144; arts of, 179; fondness ot,
for rough music, 380; attention
paid by, to personal appearance,
574; relation of the sexes among,
591.

Saviotti, Dr., division of malar bone,
39,

Saw-fly, pugnacity of a male, 291,

Saw-flies, proportions of the sexes in,
254.

Sazicola rubicola, young of, 487.

Scalp, motion of the, 13.

Scent-glands in snakes, 352.

Schaaffhausen, Prof., on the develop-
ment of the posterior molars in
different races of man, 20; on the
jaw from La Naulette, 40; on the
correlation between muscularity
and prominent supra-orbital ridges,
44; on the mastoid processes of
man, 53; on modifications of the
cranial bones, 56; on human sacri-
fices, 144; on the probable speedy
extermination of the anthropomor-
phous apes, 156; on the ancient
inhabitants of Europe, 181; on
the effects of use and disuse of
parts, 197; on the superciliary
ridge in man, 556; on the ab-
sence of race-differences in the in-
fant skull in man, 557; on ugliness,
584.

Schaum, H., on the elytra of Dytiscus
and Hydroporus, 276,

Schelver, on dragon-flies, 290.

Schiodte, on the stridulation of Hete-
rocerus, 302.

Schlegel, F. von, on the complexity of
the languages of uncivilised peo-
ples, 91.

—,, Prof., on Tanysiptera, 468.

Schleicher, Prof, on the origin of
language, 87.

Schomburgk, Sir R., on the pugnacity

SCHOOLCRAFT,

INDEX.

SEMNOPITRECUS.

675

of the male niusk-duck of Guiana,
362; on the courtship of Rupicola
crocea, 395.

Senoolcraft, Mr., on the difficulty of
fashioning stone implements, 45,
Schweinfurth, complexion of negroes,

556,

Scicna aquila, 347.

Sclater, P, L., on modified secondary
wing-feathers in the males of Pipra,
378; on elongated feathers in
nightjars, 384; on the species of
Cuasmorhynchus, 385; on the plu-
mage of Pelecanus onocrotalus,
393; on the plantaiu-eaters, 460 ;
on the sexes and young of 7adorna
varieyata, 479; on the colours of
Lemur macaco, 537 ; on the stripes
in asses, 548,

Suolecida, absence of’ secondary sexual
characters in, 260.

Scolopax frenala, tail-feathers of,
377.

— gallinago, drumming of, 376.

-—— javensis, tail-feathers of, 377.

—— major, asseinblies of, 405.

—— Wisonii, sound produced by,
377. ,

Scolytus, stridulation of, #302.

Scoter-duck, black, sexual] difference
in coloration of the, 491; bright
beak of male, 491.

Scott, Dr., on idiots smelling their
food, 36.

, J., on the colour of the beard
in man, 558,

Scrope, on the pugnacity of the male
salmon, 332; on the battles of
stags, 501,

Scudder, S. H., imitation of the
stridulation of the Orthoptera,
283; on the stridulation of the
A>sridiide, 286; on a Devonian in-
sect, 289; on stridulation, 566,

Siulpture, expression of the ideal of
beauty by, 581.

Sea-anemonies, bright colours of, 260.

Sea-bear. polygamous, 218.

Sea-elephant, male, structure of the
nose of the, 527; polygamous, 218,

Sea-lion, polygamous, 218.

Seal, bladder-nose, 528.

Seals, their sentinels generally fe-
miales, 100; evidence furnished by,
ot classification, 150; polygamous

habits of, 218; battles of tale,
500; canine teeth of male, 502;
sexual differences, 515; pairing of,
522; sexual peculiarities of, 528;
in the coloration of, 534 apprecia-
tion of music by, 569.

Sea-scorpion, sexual differences ‘n,
23

Season, changes of colour in birds, in
accordance with the, 390; changes
of plumage of birds in relation to,
462.

Seasons, inheritance at corresponding,
230,

Sebitaani, African chief, trying to
alter a fashion, 575.

Sebright Bantam, 238.

Secondary sexual characters, 207;
relations of polygamy to, 217;
transmitted through both sexes,
226; gradation of, in birds, 430,

Sedgwick, W., on hereditary tendency
to produce twins, 45.

Seemann, Dr., on the different appre-
ciation of music by different peoples,
570; on the effects of music, 571.

Seidlitz, on horns of reindeer, 506.

Selasphorus platycercus, acuminate
first primary of the male, 378.

Selby, P. J., on the habits of the
black and red grouse, 219.

Selection, double, 225.

of male by female birds, 404,

421,

, methodical, of Prussian grena-

diers, 29.

, sexual, explanation of, 209, 213,

220; influence of, on the colour-

ing of Lepidoptera, 321.

, sexual and natural, contrasted,
226,

Self-command, habit of, inherited,
115; estimation of, 118.

Self-consciousness, in animals, 83.

Self-preservation, instinct of, L12.

Selt-sacrifice, by savages, 111; esti-
mation of, 118.

Semilunar fold, 17.

Semnopithecus, 154; long hair on the
heads of species of, 150, 604.

chrysomelas, sexial ditferences

of colour in, 537.

comatus, ornamental hair oa tite
head of, 549.

—— frontatus, beard, &e., of, 550.

lat

676

SEMNOPITIIECUS.

INDEX.

SITANA,

Semnopithecus nasica, nose of, 150.

—— nemaus, colouring of, 551.

rubicundus, ornamental hair on
the head of, 548.

Senses, infe1.ority of Europeans te
savages in the, 33.

Sentinels, among animals. 100, 107.

Serpents, instinctively dreaded by
apes and monkeys, 67, 71.

Serranus, hermaphroditism in, 161.

Sex, inheritance limited by, 230.

Sexes, relative proportions of, in ran,
242, 558; probable relation of the,
in primeval man, 591.

Sexual characters, secondary, 207 ;
relations of polygamy to, 217;
transmitted through both sexes,
226; gradation of, in birds, 430.

and natural selection, con-

trasted, 226,

characters, effects of the loss of
2313 limitation of, 231.

— differences in man, 8.

selection, explanation of, 209,

213, 220; influence of, on the

colouring of Lepidoptera, 319 ; ob-

jections to, 495; action of, in man-

kind, 595.

similarity, 255.

Shaler, Prof., sizes of sexes in whaies,
516.

Sharks, prehensile organs of male,

Sharpe, Dr., Europeans in the tropics,
195.

—, R. B., on Tunysiptera sylvia,
451; on Ceryle, 457; on the young
male of Dacelo Gauich udi, 467.

Shaw, Mr., on the pugnacity of the
male salmon, 332.

_ J., on the decorations of birds,
382.

Sheep, danger-signals of, 100; sexual
diffarences in the horns of, 230;
horns of, 235, 505 ; domestic, sexual
differences of, late developed, 237 ;
numerical proportion of the sexes
wm, 246; inheritance of horns by
one sex, 505; effect of castration,
506; mode of fighting of, 508;
arched foreheads of some, 532.

— Merino, loss of horns in females
of, 2313 horns of, 235.

Shells, difference in form of, in male
and female Gasteropoda, 262,

beautiful colours and shapes of,
264,

Shield-drake, pairing with a common
duck, 414; New Zealand, sexes and
young of, 479.

Shooter, J., on the Kaffirs, 579; op
the marriage-customs of the Kaffirs,
598.

Shrew-mice, odour of, 528.

Shrike, Drongo, 461.

Shrikes, characters of young, 465.

Shuckard, W. E., .on sexual diffez-
ences in the wings of Hymenoptera,
277.

Shyness of adorned male birds, 403.

Stagonium, proportions of the sexer
in, 253; dimorphism in males of,
299,

Siam, proportion of male and female
births in, 245,

Siamese, general beardlessness of the.
560; notions of beanty of the, 578;
hairy family of, 601.

Sidgwick, H., on morality in hypo-
thetical bee community, 99; our
actions not entirely directed by
pain and pleasure, 120.

Siebold, C. T. von, on the proportion
of sexes in the Apus, 255; on the
auditory apparatus of the stridu-
lant Orthoptera, 283.

Sight, inheritance of long and short,
33.

Signal-cries of monkeys, 87.

Silk-moth, proportion of the sexes
in, 250, 251; Ailanthus, Prof.
Canestrini, on the destruction of
its larve by wasps, 251; differ-
ence of size of the male and fe-
male cocoons of the, 278; pairing
of the, 318.

Simiadz, 152; their origin and divi-
sions, 165.

Similarity, sexual, 225.

Singing of the Cicade and Fulgorida,
2815 of tree-frogs, 3503 of birds,
object of the, 368.

Sirenia, nakedness of, 56,

Sirex juvencus, 292.

Siricida, difference of the sexes .n,
292,

Siskin, 394; pairing with a canary,

Sitana, throat-pouch of the males of,
355, 358,

SIZE.

INDEX.

SPARROWS,

6977

Size, relative, of the sexes of insects,
278.

Ssin, movement of the, 13; naked-
ness of, in man, 56; colour of the,
192.

und hair, correlation of culour
of, 197.

Skull, variation of, in man, 26;
cubic contents of, no absolute test
of intellect, 54; Neanderthal, ca-
pacity of the, 55; causes of modi-
fication of the, 55; difference of,
in form and capacity, in different
races of men, 168; variability of
the shape of the, 174; differences
of, in the sexes in man, 557; arti-
ficial modification of the shape of,
575.

Skunk, odour emitted by the, 528;
white tail of, protective, 543.

Slavery, prevalence of, 117; of wo-
men, 593.

Slaves, difference between field and
house-slaves, 196.

Sloth, ornaments of male, 534.

Smell, sense of, in man and animals,
17.

Smith, Adam, on the basis of sym-
pathy, 106,

—, Sir A, on the recognition of
women by male Cynocephaii, 8 5 on
revenge by a baboon, 69; on an
instance of memory in a baboon,
74; on the retention of their colour
by the Dutch in South Africa, 193 ;
on the polygamy of the South
African antelopes, 217; on the
polygamy of the lion, 218; on the
proportion of the sexes in Kobus
ellipsiprymnus, 247 ; on Bucephalus
capensis, 351; on South African
hzards, 358; on fighting gnus,
501; on the horns of rhinoceroses,
506; on the fighting of lions, 521;
on the colours of the Cape Eiand,
535; on the colours of the gnu,
536; on Hottentot notions of
beauty, 578; disbelief in commu-
nistic marriages, 588.

w—, F., on the Cympide and Ten-
thredinid. 254; on the relative
size of the sexes of Aculeate Hymen-
optera, 279; on the difference be-
tween the sex2s of ants and bees,

92; on the stridulation of Tree |

sabulosus, 303; cn the stridulation
otf Mononychus pseudacori, 305,

Smynthurus luteus, courtship of, 279.

Snakes, sexual differences of, 351;
mental powers of, 352; male, ar-
dency of, 352.

“ Snarling muscles,” 41.

Snipe, drumming of the, 376; colo-
ration of the, 491. é

, painted, sexes and young of,

476.

, solitary, assemblies of, 405.

Snipes, arrival of male before the
female, 212; pugnacity of male,
362; double moult in, 390.

Snow-goose, whiteness of the, 492.

Social animals, affection of, for each
other, 102; defence of, by the
males, 107.

Sociability, the sense of duty con-
nected with, 98; impulse to, in
animals, 105; manifestations of,
in man, 108; instinct of, in ani-
mals, 109.

Sociality, probable, of primeval men,
62; influence of, on the develop-
ment of the intellectual faculties,
128; origin of, in man, 129.

Soldiers, American, measurements of,
29.

and sailors, difference in the
proportions of, 32.

Solenostoma, bright colours and mar-
supial sack of the females of,
346.

Song of male birds appreciated by
their females, 92; want of, in
brilliant plumaged birds, 401; of
birds, 450.

Sorex, odour of, 528,

Sounds admired alike by man and
animals, 92; produced by fishes,
347; produced by male frogs aud
toads, 350; instrumentally pro-
duced by birds, 376 et seq.

Spain, decadence of, 141.

Sparassus smaragdulus, difference of
colour in the sexes of, 272.

Sparrow, pugnacity of the male, 360;
acquisition of the Linnet’s song hy
a, 370; coloration of the, 473; 1m-
mature plumage of the, 456.

, white-crowned, young of the,
486.

Sparrows, house- and tree-, 455.

SPARROWS.

678

INDEX.

STARK,

Sparrows, new mates found by, 408.

» sexes and yeung of, 483;
learning to sing, 570.

Spathura Underwoodi, 388.

Spawning of fishes, 341, 344.

Spear, used before dispersion of man,
180.

Species, causes of tne advanvement,
of, 137; distinctive characters of,
166; or races of man, 168; steri-
lity and fertility of, when crossed,
170; supposed, of man, 174; gra-
dation of, 1753; difficulty of defin-
ing, 175; representative, of birds,
468; of birds, comparative differ-
ences between the sexes of distinct,
469,

Spectrum femoratum, difference of
colour in the sexes of, 289.

Speech. connection hetween the brain
and the faculty of, 88; connection
of intonation with music, 570.

“Spel ” of the black-cock, 375.

Spencer, Herbert, on the influence of
food on the size of the jaws, 33;
on the dawn of. intelligence, 67;
on the origin of the belief in spirit-
ual agencies, 94; on the origin of
the moral sense, 123; on music,
571, 572.

Spengel, disagrees with explanation of
man’s hairlessness, 602,

Sperm-whales, battles of male, 500.

Sphingide, coloration of the, 314.

Sphinx, Humming-bird, 317.

, Mr. Bates on the caterpillar

of a, 325,

moth, musky odour of, 308.

Spiders, 272; parental feeling in,
106 ; male, more active than female,
221; proportion of the sexes in, 254 ;
secondary sexual characters of, 272;
courtship of male, 2733 attracted
by music, 273; male, small size of,
273.

Spiosoma menthastri,
turkeys, 316.

Spine, alteration of, to suit the erect
attitude of man, 53.

Spirits, fondness of monkevs for, 7.

Spiritual agencies, beliet in, almost
universal, 94.

&piza cyanea and civis, 412,

Spoonbill, 374; Chiuese, change of
plumage ir, 461,

rejected by

Spots, retained throughout groups of
birds, 427; disappearance of, in
adult mammals, 546.

Sprengel, C. K., on the sexuality of
plants, 212.

Spring-boc, horns of the, 509.

Sproat, Mr., on the extinction of
savages in Vancouver Island, 183;
on the eradication of facial hair by
the natives of Vancouver Island,
580; on the eradication of the
beard by the Indians of Vancouver
Island, 603.

Spurs, occurrence of, in female fowls,
227, 231; development of, in
various species of Phasianide, 235;
of Gallinaceous birds, 362, 364;
development of, in female Gal-
linacea, 449.

Syuilla, different colours of the sexes
of a species of, 271.

Squirrels, battles of male, 500; Af-
rican, sexual differences in the
colouring of, 534; black, 540.

Stag, long hairs of the throat of, 521;
horns of the, 227, 229; battles of,
501; horns of the, with numerous
branches, 510; bellowing of the,
526 ; crest of the, 531.

-beetle, numerical proportion of
sexes of, 253; large size of male,
278; weapons of the male, 299.

Stainton, H. T., on the numerical
proportion of the sexes in the
smaller moths, 251; habits of Ela-
chista rufocinerea, 2523 on the
coloration of moths, 315; on the
rejection of Spilosoma menthastri,
by turkeys, 316; on the sexes of
Agrotis exclamationis, 316.

Staley, Bishop, mortality of infant
Maories, 187.

Stallion, mane of the, 521.

Stallions, two, attacking a third, 101;
fighting, 501; small canine teeth
of, 514

Stansbury. Capt.,
pelicans, 102,

Staphylinide, hornlike processes in
male, 299

Starfishes, parental feeling wm, 106;
bright colours of some, 260.

Stark, Dr., on the death-rate in towns
and rural districts, 1383 on the
influence of marriage un mortality.

observations on

STARLING.

INDEX.

SUPRA-CONDYLOID.

679

139; on the higher mortality of
males in Scotland, 243.

Starling, American field-, pugnacity of
male, 367,

—, red-winged, selection of a mate
by the female, 416.

Starlings, three, frequenting the same
nest, 219, 409; new mates found
by, 408.

Statues, Greek, Egyptian, Assyrian,
&c., contrasted, 581.

Stature, dependence of, upon local
influences, 31.

Staudinger, Dr., on breeding Lepid-
optera, 251; his list of Lepid-
optera, 252,

Staunton, Sir G., hatred of indecency
a modern virtue, 119.

Stealing of bright objects by birds,
413.

Stebbing, T. R., on the nakedness of
the human body, 6v0.

Stemmatopus, 522.

Stendhal, see Bombet.

Stenobothrus pruto wn, stridulation,
286, j

Stephen, Mr. L., on the difference in
the minds of men and animals, 78;
on general concepts in animals,
89; distinction between material
and formal morality, 111.

Sterility, general, of sole daughters,
135; when crossed, a distinctive
character of species, 166; under
changed conditions, 189, 191.

Sterna, seasonal change of plumage in,
493.

Stickle-back, polygamous, 220 ; male,
courtship of the, 331; male, bril-
liant colouring of, during the breed-
ing season, 340; nidification of the,
349.

Sticks used as implements and wea-
pons by monkeys, 81.

Sting in bees, 208.

Stokes, Capt., on the habits of the
great bower-bird, 381.

Stoliczka, Dr., on colours in snakes,
352,

Stonechat, young of the, 487.

Stone implements, difficulty of making,
49; as traces of extinct tribes, 181.

“one;, used by menkeys for breaking
hard fruits ant as missiles, 50;
piles 2f. 179.

Stork, black, sexual differences in the
bronchi of the, 374; red beak of
the, 491.

Storks, 491, 493; sexual difference
iu the colour of the eyes of, 425.

Strange, Mr., on the satin bowe:
bird, 381,

Stretch, Mr., on the numerical pro-
portion in the sexes of shickens,
247,

Strepsiceros kudu, horns of, 512; mark-
ings of, 543.

Stridulation, by males of Theridion,
274; of the Orthoptera and Homop-
tera discussed, 289; of beetles,
301.

Stripes, retained throughout groups
of birds, 427; disappearance of, in
adult mammals, 546.

Strix flammea, 408.

Structure, existence of unserviceable
modifications of, 61.

Struggle for existence, in man, 142,
146.

Struthers, Dr., on the occurrence of
the supra-condyloid furamen in the
humerus of man, 21.

Sturnelia ludoviciana, pugnacity of the
male, 367.

Sturnus vulgaris, 408.

Sub-species, 175.

Suffering, in strangers, indifference ot
savages to, 117.

Suicide, 137; formerly not regarded
asa crime, 117; rarely practised
among the lowest savages, 117.

Suida, stripes of young, 464.

Sulivan, Sir B. J., on speaking of
parrots, 85; on two stallions at-
tacking a third, 501.

Sumatra, compression of the nose by
the Malays of, 583.

Sumner, Archb., man alone capable of
progressive improvement, 79.

Sun-birds, nidification of, 454.

Superstitions, 144; prevalence of,
122.

Superstitious customs, 96.

Superciliary ridge in man, £56, 558.

Supernumerary digits, more frequent
in men than in women, 223; in-
heritance of, 232; early develup-
ment of, 237.

Supra-condyloid foramen in the early
progenitors of man, 160.

680

SUSPICION.

INDEX.

TEMPER.

Suspicion, prevalence of, among ani-
mals, 69.

Swallow-tail butterfly, 312.

Swallows deserting their young, 108,
113.

Swan, black, wild, trachea of the,
374; white young of, 482; red beak
of the, 491; black-necked, 493.

Swans, 491, 493; young, 481.

Swaysland, M:., on the arrival of
migratory birds, 212,

Swifts, migration of, 108.

Swinhoe, R., on the common rat in
Formosa and China, 80; behaviour
of lizards when caught, 355; on
the sounds produced by the male
hoopoe, 3763 on Dicrurus macro-
cercus and the spoonbill, 461; on
the young of Ardeola, 468; on the
habits of Turniz, 476; on the
habits of Rhynchaa bengalensis,
476; on Orioles breeding in imma-
ture plumage, 484,

Sylvia atricapilla, young of, 487.

cinerea, aerial love-dance of the
male, 380

Sympathy, 134 ; among animals, 102;
its supposed basis, 106.

Sympathies, gradual widening of,
123,

Syngnathous fishes, abdominal pouch
in male, 163.

Sypheotides auritus, acuminated pri-
maries of the male, 378; ear-tufts
of, 384

T.

Tabanide, habits of, 208.

Tadorna variegata, sexes and young
of, 479,

vulpanser, 414.

Tahitians, 145; compression of the
nose by the, 583.

Tail, rudimentary, occurrence of, in
man, 22; convoluted body in the
extremity of the, 23; absence of,
in man and the higher apes, 58;
variability of, in species of Macacus
and in baboons, 58 ; presence of, in
the early progenitors of man, 160;
length of, in pheasunts, 445, 451,
452; dilference of length cf the,
in the twe sexes of birds, 451.

Tait, Lawsun, on the effects of na-

tural selection on civilised nations.
133,

Tanager, scarlet, variation in the
male, 424,

Tanagra estiva, age of mature plu-
mage in, 483.

rubra 424; young of, 487.

Tanais, absence of mouth in the males
of some species of, 208; relations
of the sexes in, 455; dimorphic
males of a species of, 265.

Tankerville, Earl, on the battles of
wild bulls, 501.

Tanysiptera, races of, determined from
adult males, 468.

— sylvia, long tail-feathers of, 451.

Taphroderes distortus, enlarged lett
mandible of the male, 277.

Tapirs, longitudinal stripes of young,
464, 546.

Tarsi, dilatation of front, in male
beetles, 275.

Tursius, 156. *

Tasmania, half-castes killed by the
natives of, 170.

Tasmanians, extinction of, 184.

Taste, in the Quadrumana, 541.

Tattooing, 178; universality of, 574.

Taylor, G., on Quiscalus major, 248.

Tea, fondness of monkeys for, 7.

Tear-sacks, of Ruminants, 529.

Teebay, Mr., on changes of plumage
in spangled Hamburgh fowls, 229.

Teeth, rudimentary incisor, in Rumi-
nants, 11 ; posterior molar, in man,
20; wisdom, 20; diversity of, 26;
canine, in the early progenitors or
man, 160; canine, of male mam-
mals, 502; in man, reduced by
correlation, 562; staining of the,
574; front, knocked out or filed
by some savages, 575.

Tegetmeier, Mr., on the transmission
of colours in pigeons by one sex
alone, 231; numer:cal proportion
of male and female births in dogs,
246; on the abundance of male
pigeons, 247; on the wattles of
game-cocks, 403 ; on the courtship
of fowls, 417; on the loves of pigeons,
418; on dyed pigeons, 418; blue
dragon pigeons, 446,

Tembeta, 8. American ornament, 575,

Temper, in dogs and horses, inherited,
6Y.

VENCHL,

INDEX.

681

TOADS,

Tench, proportions of the sexes in the
249; brightness of male, during
breeding season, 340.

Tenebrioniija, stridulation of, 302.

Tennent, Sir J. E., on the tusks of
the Ceylon” Elephant, 507, 5153
on the frequent absence of beard in
the natives of Ceylon, 560 ; on the
Chinese opinion of the aspect of
the Cingalese, 578.

fennyson, A., on the control of
thought, 123,

Tenthredinidz, proportions of the
sexes in, 254; fighting habits of
male, 291; difference of the sexes
in, 292.

Tephrodornis, young of, 468.

Terai, in India, 182.

Termites, habits of, 291.

Terns, white, 492; and black, 495.

, seasonal change of plumage in,

492.

Terror, common action of, upon the

lower animals and man, 69.

Testudo elegans, 351.

nigra, 351,

‘Letrao cupido, battles of, 367 ; sexual
difference in the vocal organs of,
371.

—— phasianellus, dances of, 380;
duration of dances of, 405.

—— scotius 455, 465, 471.

tetriz, 455, 465,471; pugnacity

of the male, 363.

umbellus, pairing of, 367 ; battles
of, 367; drumming of the male,
375.

—— urogalloides, dances of, 405.

—— urogullus, pugnacity of the male,
363.

urophasianus, inflation of the
esophagus in the male, 372.

Thamnobia, young of, 468.

Thraumalea picta, display of plumage
by the male, 396.

Tiecla, sexual differences of colouring
in species of, 310.

«~—— rubi, protective colouring of,
312,

Thecophora fovea, 308.

Theognis, selection in mankind, 29.

Jheridion, stridulation of males of,
273.

— lineatwn, 272.

Thomisus citreus, and TZ. flovicolens,

difference of colour in the sexes of,
272.

Thompson, J. H., on the battles of
sperm-whales, 500.

, W., on the colouring of the
male char during the breeding
season, 340; on the pugnacity of
the males of Gallinula chloropus,
360; on the finding of new mates
by magpies, 407; on the finding of
pew mates by Peregrine falcons,
408,

Thorax, processes of, in male beetles,
295.

Thorell, T., on the proportion of the
sexes in spiders, 255,

Thornback, difference in the teeth of
the two sexes of the, 334.

Thoughts, control of, 123.

Thrush, pairing with a blackbird,
414; colours and nidification of
the, 455.

Thrushes, characters of young, 455,
464,

Thug, remorse of a, 117.

Thumb, absence of, in dteles and Hy-
lubates, 51,

Thury, M., on the numerical propor-
tion of male and female births
among the Jews, 243.

Thylacinus, possession of the marsupial
sack by the male, 161

Thysanura, 279.

Tibia, dilated, of the male Crabo cri-
brarius, 276,

and femur, proportions of, iu
the Aymara Indiaus, 34.

Tierra del Fuego, marriage-customs
of, 598.

Tiger, colours and markings of the,
545,

Tigers, depopulation of districts by, in
India, 46,

Tillus elongatus, difference of colour
in the sexes of, 294,

Timidity, variability of, in the same
species, 69.

Tineina, proportion of the sexes in,
250.

Tipula, pugnacity of male, 280.

Tits, sexual difference of colour in,

- 458,

Toads, 349; male, treatment of ova
by some, 163; male, ready to breed
before the female, 212.

682

TODAS.

INDEX.

TURDUS.

Todas, infanticide and proportion of
sexes, 255; practise pciyandry,
593; choice of husbands amongst,
593.

Toe. great, condition of, in the human
embryo, (1,

Tomicus viliosns proportion of the
sexes in, 253,

Tomtit, blue, sexual difference of co-
lour in the, 453.

Tonga Islands, beardlessness of the
natives of, 560, 581.

Tooke, Horne, on language, 86.

Tools, Hint, 145; used by monkeys,
815 use of, 48,

Topknots in birds, 384.

Tortoise, voice of the male, 557,

Tortures, submitted to by American
savages, 118.

Totanus, double moult in, 390,

Toucans, colours and nidification of
the, 455; beaks and ceres of the,
491.

Towns, residence in, a cause of dimi-
nished stature, 31.

Toynbee, J., on the external shell of
the ear in man, 14.

‘Trachea, convoluted and imbedded in
the sternum, in some birds, 374;
structure of the, in Roynchea, 476.

Trades, affecting the form of the
skull, 56.

Trayelaphus, sexual
colour in, 535.

scriptus, dorsal crest of, 530;
markings of, 543, 544.

Tragopan, 220; swelling of the wat-
tles of the male, during courtship,
383; display of plumage by the
male, 397; markings of the sexes
of the, 428.

T-ugops dispar, sexual difference in
the colour of, 351,

Training, effect of, on the mental
difference between the sexes of
man, 585.

Tianster of male characters to female
birds, 470.

Transmission, eal, of ornamental
characters, to both sexes in mam-
mals, 5 +2.

Traps, avoidance of, by animals, 80;
use of, 48.

Treachery, to comrades avoidance of,
by savages, 111

differences of

Tremex: columba, 292.

Tribes, extinct, 128; extinction of,
182.

Trichius, difference of colour in the
sexes of a species of, 294.

Trigla, 347,

Trimen, R., on the proportion of the
sexes in South African butterflies,
250; on the attraction of males by
the female of Lasiocampa quercus,
252; on Pneumora, 288; on dif-
ference of colour in the sexes o!
beetles, 294; on moths brilliantly
coloured beneath, 315; on mimicry
in butterflies, 325; on Gyn isa
Zsis, and on the ocellated spots of
Lepidoptera, 428; on Cyllo Leds
429,

Tringa, sexes and young of, 485.

cornuta, 391.

Triphent, coloration of the species
of, 313.

Tristram, H. B., on unhealtny dis-
tricts in North Africa, 194; or
the habits of the chaffinch in Pales-
tine, 248; on the birds of the
Sahara, 456; on the animals in-
habiting the Sahara, 489.

Tritun cristatus, 348.

pumipes, 348.

pinetutus, 348.

Troglodyte skulls, greater than those
of modern Frenchmen, 55.

Trowlodytes vulgaris, 473.

Trogons, colours and nidification of
the, 455, 456.

Tropic-birds, white only when mature,
492.

Tropies, freshwater fishes of the,
343.

Trout, proportion of the sexes in,
249; male, pugnacity of the, 332.

Trox salulosus, stridulation of, 303.

Truth, not rare between members of
the same tribe, 118; more highly
appreciated by certain tribes, 122.

Tulloch, Major, ou the immunity of
the negro from certain fevers, 193,

Tumbler, almond, change of plumage
in the, 238.

Tu dus merula, 4555 young of, 487

— migrutorius, 464.

—— musicus, 455.

polyglottus, young of, 487.

torquatus, 455

TURKEY INDEX. VARIOLA. 683
Turkey, wild, pugnacity of young
male, 366 ; wild, notes of the, 375; U

swelling of the wattles of the male,
383; variety of, with a top-knot,
384; recoguition of a dog by a, 412 ;
male, wild, acceptable to domesti-
cated females, 418; wild, first ad-
vances made by older females, 419 ;
wild, breast-tuft of bristles of the,
461.

Turkey-cock, scraping of the wings
of, upon the ground, 375; wiid,
display of plumage by, 394; fight-
ing habits of, 404.

Turner, Prof. W., on muscular fasci-
culi in man referable to the pan-
nicuius carnosus, 13; on the occur-
rence of thesupra-condyloid foramen
in the hnman humerus, 21; on
muscles attached to the coccyx in
man, 22; on the filum terminale in
man, 23; on the variability of the
muscles, 26 ; on abnormal conditions
of the human uterus, 39; on the
development of the mammary
glands, 162; on male fishes hatch-
ing ova in their mouths, 163, 345;
on the external perpendicular fissure
of the brain, 200; on the bridging
convolutions in the brain of a chim-
panzee, 201.

Turnix, sexes of some species of, 475 ;
480.

Turtle-dove, cooing of the, 374.

Tuttle, H., on the number of species
of man, 174.

Tylor, E. B., on emotional cries, ges-
tures, &e., of man, 85; on the
origin of the belief in spiritual
agencies, 94; remorse for violation
of tribal usage in marrying, 115;
on the primitive barbarism of
civilised nations, 143 ; on the origin
of counting, 144; inventions of
savages, 145; on resemblances, of
the mental characters in different
races of man, 178.

Type of structure, prevalence of, 164,

Typheeus, stridulatiug organs of, 301 5
stridulation of, 303.

Tyromg ¢ estiva, 462.

Twins, tendency to produce, here-
ditary, 45.

Iwite, proportion uf the sexes in ‘he,
248,

Ugliness, said to consist in an approach
to the lower animals, 584

Umbrella-bird, 373,

Umbrina, sounds produced by, 347.

United States, rate of increase in, 44 ;
influence of natural selection on
the progress of, 142; change under-
gone by Europeans in the, 196.

Upupu epops, sounds produced by the
male, 376.

Uraniida, coioration of the, 314.

Uvia troile, variety of (= U. lacru-
mans), 424.

Urodela, 348.

Urosticte Benjamini, sexual differences
in, 442,

Use and disuse of parts, effects of, 32,
influence of, on the races of man,
197,

Uterus, reversion in the, 38; more or
less divided, in the human subject,
38, 43; double, in the early pro-
genitors of man, 161.

Vv.

Vaccination, influence of, 134.

Vancouver Island, Mr. Sproat on the
savages of, 183; natives of, eradi-
cation of facial hair by the, 580.

Vanellus cristutus, wing tubercles of
the male, 366.

Vaness@, 308; resemblance of lower
surface of, to bark of trees, 311.
Variability, causes of, 28; in man,
analogous to that in the lower
animals, 29; of the races of man,
174; greater in men than in
women, 223; period of, relation of
the, to sexual selection, 240; of
birds, 422; of secondary sexuai

characters in man, 559.

Variation, laws of, 293; correlated,
43; in man, 146; analogous, 152+
analogous, in plumage of birds, 38.5

Variations, spontaneous, 44,

Varieties, absence of, between two
species, evidence of their distinct-
ness, 167,

Variety, an object in nature, 493,

Vaniola,communicable between man
and the lower animals, 7.

VAUREAL,

634

INDEX.

WALLACE.

Vauréal, human bones from, 22.

Veddahs, monogamous habits of, 591.

Veitch, Mr., un the aversion of
Japanese ladies to whiskers, 581.

Vengeance, instinct of, 113.

Venus Erycina, priestesses of, 587.

Vermes, 264,

Vermiform appendage, 21.

Verreaux, M., on the attraction cf
numerous males by the female of
an Australian Bombyx, 252.

Vertebra, caudal, number of, in
macaques and baboous, 58; of
monkeys, partly imbedded ia the
body, 59.

Vertebrata, 330; common origin of
the, 158; most ancient progenitors
of, 1613; origin of the voice in air-
breathing, 567.

Veswula prostatica, the homologue of
the uterus, 24, 161.

Vibrissz, represented by long hairs
in the eyebrows, 19.

Vidua, 403, 462.

axillaris, 219.

Villerme, M., on the influence of
plenty upon stature, 31.

Vinson, Aug., courtship of male
spider, 273; on the male of Epcira
nigra, 273.

Viper, difference of the sexes in the,
351,

Virey, on the number of species of
man, 174,

Virtues, originally social only, 116;
gradual appreciation of, 151.

Viseera, variability of, in man, 27.

Viacovich, Prof., on the ischio-pubic
muscle, 41.

Vocal music of birds, 368.

organs of man, 87; of birds, 90,
450; of frogs, 350; of the Inses-
sores, 370; difference of, in the
sexes of birds, 371 primamly used
in relation to the propagation of
the species, 564.

Vogt, Karl, on the origin of species, 1;
on the origin of man, 3; on the
semilunar fold in man, 17; on mi-
crocephalous idiots, 35; cn the imi-
tative faculties of microcephalons
idiots, 87; on skulls from Brazilian
caves, 168; on the evolution of the
races of mau, 177; vu the formation
of the skull in womea, 557; on the

Ainos and negroes, 560; on the ins
creased cranial difference of tha
sexes in man with race deveiopment,
586; on the obliquity ot’ the eye in
the Chinese and Japanese, 578.

Voice in mammals, 525; in monkeys
and man, 5083; in man, 566; origin
of, in air-breathing vertebrates, 567,

Von Baer, definition of advancemcat
in the organic scale, 164.

Vulpian, Prof., on the resemblance
between the brains of man and of
the higher apes, 6.

Vultures, selection of a mate by the
temale, 410; colours of, 493

Ww.

Waders, young of, 486.

Wagner, R., on the occurrence of the
diastema in a Kaffir skull, 40; ou
the bronchi of the black stork, 374.

Wagtail, Ray’s, arrival of the male
before the female, 212.

Wagtails, Indian, young of, 46%.

Waist, proportions of, in soldiers and
sailors, 32.

Waitz, Prof., on the number of spe-
cies of man, 174; on the liability
of negroes to tropical fevers atter
residence in a cold climate, 194;
ou the colour of Australian infants,
558; on the beardlessness of
negroes, 560; on the fondness of
mankind for ornaments, 573; on
negro ideas of temale beauty, 579;
on Javan and Cochin Chinese ideas
of beauty, 580.

Walckenaer and Gervais, spider at-
tracted by music, 273; on the Myri-
apoda, 274,

Waldeyer, M , on the hermaphroditism
of the vertebrate embryo, L61.

Wales, North, numerical proportion ot
male and female births in, 242.

Walker, Alex., on the large size of the
hands of labourers’ children, 32.

, F., on sexual diferences in
the diptera, 280.

Wallace, Dr. A., on the prehensile
use of the tarsi in male mcths, 209;
ou the rearing of the Ailanthus
silkmoth, 251; on breeding Lepi-
doptera, 251; proportion of sexes of
Bombyx cynthia, B. yamumai, and

WALLACE,

INDEX.

WATERIIOUSE.

685

B. Pernyi reared by, 253; on the
development of Bombyx cynthia
and B, yamamai, 278 ; on the pair-
ing of Bombyx cynthia, 318.
Wallace, A. R., on the origin of
man, 3; on the power of imitation
in man, §8; on the use of missiles
by the orang, 82; on the varying
appreciation of truth among differ-
ent tribes, 122; on the limits of
natural selection in man, 49, 127;
on the occurrence of remorse among
savages, 131; on the effects of
natura] selection on civilised na-
tions, 133; on the use of the con-
vergence of the hair at the elbow in
the orang, 1513; on the contrast in
the characters of the Malays and
Papuans, 168; on the line of sepa-
ration between the Papuans and
Malays, 169; on the birds of para-
dise, 219; on the sexes of Ornithup-
tera Cresus, 250; on protective re-
semblances, 261; on the relativesizes
of the sexes of insects, 278; on Ela-
phomyia, 280; on the pugnacity of
the males of Leptorhynchus angus-
tatus, 299; on sounds produced by
Euchirus longimanus, 304; on the
colours of Diadema, 309; on Kal-
lima, 311; on the protective colour-
ing of moths, 313; on bright colora-
ration as protective in butterflies,
3145 on variability in the Papi-
lionid, 320; on male and female
butterflies inhabiting different sta-
tions, 321 ; on the protective nature
of the dul! colouring of female but-
tertlies, 321, 322, 325; on mimicry
in butterflies, 324; on the bright
colours of caterpillars, 325; on
brightly-coloured fishes frequenting
reefs, 343; on the coral snakes, 353 ;
on Paradisea apoda, 385; on the
display of plumage by male birds
of paradise, 395; on assemblies of
birds of paradise, 405; on the in-
stability of the ocellated spots in
Hipparchia Janira, 428; on sexually
limited inheritance, 444; on the
sexual coloration of birds, 452, 472,
473, 475, 480; on the relation be-
tween the colours and nidification
of birds, 452, 455; on the colora-
tier of the Cotingide, 460; on the

females of Paradisea apoda and
papuana, 470; on the incubation
of the cassowary, 478 ; on protective
coloration in birds, 489; on the
Babirusa, 519; on the markings of
the tiger, 5455; on the beards of the
Papuans, 560; on the hair of the
Papuans, 575; on the distrilution
of hair on the human bedy, 600.

Walrus, development of the nicti-
tating membrane in the, 17; tusks
of the, 502, 507; use of the tusks
by the, 513.

Walsh, B. D., on the propertion of
the sexes in Papilio Turnus, 250;
on the Cynipide and Cecidomyide,
2543; on the jaws of Ammophila,
275; on Corydalis cornutus, 275;
on the prehensile organs of male
insects, 275; on the antenne of
Penthe, 275; on the caudal appen-
dages of dragon-flies, 276 ; on Platy-
phyllum concivum, 286 ; on the sexes
of the Ephemeride, 289; on the
difference of colour in the sexes of
Spectrum femoratum, 2893 on sexes
of dragon-flies, 290; on the differ-
ence of the sexes in the Ichneu-
,monide, 292; on the sexes of Orso-
dacna atra, 294; on the variation
of the horns of the male Phaneus
carnifex, 297; on the coloration of
the species of Anthucharis, 312.

Wapiti, battles of, 501; traces of
horns in the female, 504; attacking
a man, 511; crest of the male, 531;
sexual difference in the colour of
the, 536.

Warbler, hedge-, 473 ; young of the,
481.

Warblers, superb, nidification of, 454

Wariness, acquired by animals, 80.

Warington, R., on the habits of the
stickle-backs, 331, 345; on the
brilliant colours of the male
stickle-back during the breeding
season, 340.

Wart-hog, tusks and pads of the, 519.

Watchmakers, short-sighted, 33.

Waterhen, 360.

Waterhouse, C. O., on blind beetles,
2943; on difference of colour in
the sexes of beetles, 294.

. G. R., on the voice of Hylobates

agilis, 567,

686

WATER-OUZEL,

INDEX.

WESTWOOD.

Water-ouzel, 455; autumn song of
the, 370.

Waterton, C., on the Bell-bird, 389 ;
on the pairing of a Canadi goose
with a Bernicle gander, 4143; on
hares fighting, 500.

Wattles, disadvantageous
birds in fighting, 404.

Weale, J. Mansel, on a South African
caterpillar, 325.

Weaith, influence of, 134.

Weapons, used by man, 48; emploved
by monkeys, 81 ; oltensive, of males,
210; of mammals, 501 et sey.

Weaver-bird, 370.

Weaver-birds, rattling of the wings
of, 375; assemblies of, 405,

Webb, Dr., on the wisdom teeth, 20.

Wedderburn, Mr., assembly of black
game, 407.

Wedgwood, Hensleigh, on the origin
of language, 87.

Weevils, sexual difference in length of
snout in some, 208.

Weir, Harrison, on the numerical
proportion of the sexes in pigs and
rabbits, 247; on the sexes of young
pigeons, 247; on the songs of birds,
368; on pigeons, 411; on the dis-
like of blue pigeons to other co-
loured varieties, 417; on the de-
sertion of their mates by fema.e
pigeons, 418,

— , J. Jenner, on the nightingale
and biackcap, 212; on the relative
sexual maturity of male birds, 213 ;
on female pigeons deserting a feeble
mate, 214; on three starlings fre-
quenting the same nest, 219; on
the proportion of the sexes in Mu-
chetes puynaz and other birds, 247,
248; on the coloration of the, 77<-
phene, 313; on the rejection of
certain caterpillars by birds, 326 ;
on sexual differences of the beak in
the goldfinch, 360; on a piping
bullfinch, 369 ; on the object of the
nightingale’s song, 368; on song-
birds, 369; on the pugnacity of
male fine-plumaged birds, 400; on
the courtship of birds, 401; on the
finding of new mates by Peregrine-
falcons and Kestrels, 408; on the
balifinch and starling, 408 ; on the
cause of birds remuining unpaired,

to male

409 ; on starlings and parrots living
in triplets, 409; on recognition of
colour by birds, 411; on hybrid
birds, 414; on the selection of a
greenfinch by a female canary, 415 ;
on a case of rivalry of female bull-
finches, 420; on the maturity otf
the golden-pheasant, 483.

Weisbach, Dr., measurement of men
of different races, 167; on the
greater variability of men than of
women, 223; on the relative pro-
pertions of the body in the sexes of
different races of man, 559.

Weismann, Prot., colours of Lycene,
312.

Welcker, M., on brachycephaly and
dolichucephaly, 56; on sexual dif-
ferences in the skull in man, 557.

Wells, Dr., on the immunity of co-
loured races from certain poisons,
193.

Westring, on the stridulation of males
ot Theridion, 273; on the stridu-
lation of Reduvius personatus, 281 ;
on the stridulation of beetles, 302 ;
on the stridulation of Omaloplia
brunnea, 303; on the stridulatiag
organs of the Coieoptera, 304;
on sounds produced by Cychrus,
304,

Westropp, H. M., on reason in a bear,
76; on the prevalence of certain
forms of ornamentation, 179.

Westwood, J. O., on the classification
of the Hymenoptera, 148; on the
Culicide and Tabanide, 208; on a
Hymenopterous parasite with a
sedentary male, 221; on the pro-
portions of the sexes in Lucanus
cervus and Siayonium, 253; on the
absence of ocelli in female mu-
tillide, 274; on the jaws of Am-
mophila, 275; on the copulation of
insects of distinct species, 275; on
the male of Crabro cribrarius, 276
on the pugnacity of male 7ipule,
280 ; on the stridulatiou of Pirates
stridulus, 281; on the Cicada, 281;
on the stridulating organs of the
crickets, 284; on E’phippiger vitium,
284, 288; on Pneumora, 287; on
the pugnacity of the Mantides, 289+
on Platyblemnus, 289 ; on differenca
iu the sexes of the Agrionida, 290;

WILALE,

INDEX.

WOODPICK ERS.

687

on the pugnacity of the males of a
species of Tenthreding, 291; on
the pugnacity of the male stag-
beetle, 299; on Bledius taurus and
Siagonium, 299; on lamellicorn
beetles, 301; on the coloration of
Siithosia, 314.

Whale, Sperm-, battles of male, 500.

Whales, nakedness of, 56.

Whately, Archb., language not pe-
culiar to man, 84; on the primitive
civilisation of man, 143.

Whewell, Prof., on maternal affection,
70.

Whiskers, in monkeys, 150.

White, F. B., noise produced »y ZH fc-
phila, 308.

, Gilbert, on the proportion of
the sexes in the partridge, 248 ; on
the house-cricket, 283 ; on the ob-
ject of the song of birds, 369; on
the finding of new mates by white
owls, 408 ; on spring coveys of male
partridges, 409.

Whiteness, a sexual ornament in
some birds, 494; of mammals in-
habitiag snowy countries, 542.

White-throat, aérial love-dance of the
male, 380,

Whitney, Prof., on the development
of language, 86; language not in-
dispensable for thought, 88.

Widow-bird, polygamous, 219 ; breed-
ing plumage of the male, 392,
403; female, rejecting the un-
adorned male, 419.

Widows and widowers, mortality of,
140.

Wigeon, pairing with a pintail duck,
414, .

Wilckens, Dr., on the modification of
domestic animals in mountainous
regions, 35; on a numerical re-
lation between the hairs and excre-
tory pores in sheep, 198.

Wilder, Dr. Burt, on the greater fre-
quency of supernumerary digits in
men than in women, 223.

Williams, on the marriage-customs ot
the Fijians, 599.

Wilson, Dr., on the conical heads of
the natives of North-Western Ame-
rica, 583; on the Fijians, 583; on
the persistence uf the fashion of
compressing the skull, 584.

Wing-spurs, 449.

Wings, differences of, in the two sexes
of butterflies and Hymenoptera,
277; play of, in the courtship os
birds, 401.

Winter, change of colour of mam-
mals in, 542.

Witchcraft, 96,

Wives, traces ef the forcible capture
of, 144.

Wolf, winter change of the, 542.

Wolff, on the variability of the vis-
cera in man, 27,

Wollaston, T. V., on Hurygnathus,
277; on musical Curculionide, 301 ;
on the stridulation of Acadles, 300.

Wolves learning to bark from dogs,
73; hunting in packs, 101.

, black, 540.

Wombat, black varieties of the, 539.

Women distinguished from men by
male monkeys, 8; preponderance of,
in numbers, 244; selection of, for
beauty, 397; effects of selection
of, in accordance with differen‘
standards of beauty, 584; practice
of capturing, 589, 592; early be-
trothals and slavery of, 593; free-
dom of selection by, in savage
tribes, 598,

Wonler, manifestations of, by ani-
mals, 71.

Wonfor, Mr., on sexual peculiarities
in the wings of butterflies, 277.
Wood, J., on muscular variations in
man, 26, 41, 43; on the greater
variability of the muscles in men

than in women, 223,

, T. W., on the colouring of the
orange-tip butterfly, 313; on the
habits of the Saturniide, 315;
quarrels of chamaleons, 357; on
the habits of Menura Alberti, 371;
on Zetrao cupido, 371; on the dis-
play of plumage by male pheasants,
3963; on the ocellated spots of the
Argus pheasant, 441; on the habita
of the female cassowary, 478.

Woodcock, coloration of the, 491.

Woodpecker, selection of a mate by
the female, 416.

Woodpeckers, 371; tapping of, 376;
colours and ridification of the, 455,
458, 489; characters of young, 46a,
474, 481,

688

WOCLNER. INDEX. ZYGANIDE.
Weolner, Mr., onservations on tne
ear in man, 15,
Wormald, Mr., on the coloration of Y.

Hupopyra, 315.

Wounds, healing of, 8.

Wren, 473; young of the, 481.

Wright, C. A., on the young of Oro-
cetes and Petrocincla, 487.

-——-, Chauncey, great brain-power
requisite for language, 48; on cor-

relative acquisition, 571; on the |

enlargement of the brain in man,
610,

—,, Mr., on the Scotch deerhound,
517; on sexual preference in dogs,
524; on the rejection of a horse
by a mare, 525.

, W. von, on the protective plu-
mage of the Ptarmigan, 391.

Writing, 144.

Wyman, Prof., on the prolongation of
the coccyx in the human embryo,
11; on the condition of the great
toe in the human embryo, 11; on
the occurrence of the supra-condy-
loid foramen in the humerus of
man, 225 on variation in the skulls
of the natives of the Sandwich
Islands, 26; on the hatching of the
eggs in the mouths and branchial
cavities of mate fishes, 163, 345.

x.

Xenarchus, on the Cicadz, 281.

Xenophon, selection in mankind advo-
cated by, 29.

Xenorhynchus, sexual difference in the
colour of the eyes in, 425.

Xipophorus Hellerii, peculiar anal fin
of the male, 337, 338.

Xylocopa, difference of the sexes in,
292.

Yarrell, W., on the habits of the
Cyprinide, 250; on Raia clavata,
331; on the characters of tne male
salmon during the breeding season,,
832, 342; on the characters of the
rays, 334; on the gemmeous drago~
net, 336; on the spawning of the
salmon, 344; on the incubation of
the Lophobranchii, 346 ; on rivalry
in song-birds, 369; on the trachea
of the swan, 374; on the moulting
of the Anatide, 393 ; on the young
of the waders, 486.

Yellow fever, immunity of negroes
and mulattoes from, 193.

Youatt, Mr., on the development of
the horns in cattle, 235.

Yura-caras, their notions of beauty,
580.

Z.

Zebra, rejection of an ass by a female,
540; stripes of the, 545

Zebus, humps of, 532.

Zigzags, prevalence of, as ornaments,
179.

Zincke, Mr., on European emigration
to America, 142.

Zootoca vivipara, sexua) difference in
the colour of, 357.

Zouteveen, Dr., polydactylism, 37;
proportion of sexes at Cape of Good
Hope, 243; spiders attracted by
music, 273; on sounds produced by
fish, 347.

Zygenidz, coloration of the, 314,

THE END.