1 1

the

DESCENT OF MAN

SELECTION IN RELATION TO SEX.

BY

CHARLES DARWIN, M.A., F.R.S., Etc.

WITH ILLUSTRATIONS.
IN TWO VOLUMES. — Vol. II.

NEW YOE K :
D. APPLET ON ANT) COMPANY,
549 & 551 B ROADWAY.
1871.

library of
Jhe ^Wh Collene of
Hawaii

H J*

'gr/ m

CONTENTS.

PART n.

SEXUAL SELECTION— continued.
CHAPTER XII.

SECONDARY SEXUAL CHARACTERS OP FISHES, AMPHIBIANS, AND REPTILES.

Fishes : Courtship and Battles of the Males. — Larger Size of. the Females. —
Males, Bright Colors and Ornamental Appendages; other Strange
Characters. — Colors and Appendages acquired by the Males during the
Breeding-season alone. — Fishes with both Sexes brilliantly colored. —
Protective Colors. — The less Conspicuous Colors of the Female cannot
bo accounted for on the Principle of Protection. — Male Fishes building
Nests, and taking Charge of the Ova and Young. Amphibians : Differ-
ences in Structure and Color between the Sexes. — Vocal Organs. Rep-
tiles : Chelonians. — Crocodiles. — Snakes, Colors in some Cases pro-
tective.— Lizards, Battles of. — Ornamental Appendages. — Strange Dif-
ferences in Structure between the Sexes. — Colors. — Sexual Differences
almost as great ^as with Birds . . . . . p. 1

CIIAPTEK XIII.

SECONDARY SEXUAL CHARACTERS OP BIRDS.

Sexual Differences. — Law of Battle— Special "Weapons. — Vocal Organs.—
Instrumental Music. — Love-Antics and Dances.— Decorations, lYrma-
nont and Seasonal. — Double and Single Annual Moults. — Display of
Ornaments by the Males ...... 30

CH APTEE XIV.
niuns — continued.

Choice exerted by the Female. — Length of Courtship. — Unpaired Birds. —
Mental Qualities and Taste for the Beautiful.- Preference or Antip-
athy shown by the Female foi Partloulai Males.- - Yai nihility of

20111

iv

CONTEXTS.

Birds.— Variations sometimes abrupt.— Laws of Variation.— Formation
of Ocelli. — Gradations of Character. — Case of Peacock, Argus Pheas-
ant, and Urosticte . . . * • • . p. 95

CHAPTER XV.
bi uns — continued.

Discussion why the Males alone of some Species, and both Seles of other
Species, are brightly colored. — On Sexually-limited Inheritance, as ap-
plied to Various Struetures and to Bri^htl v-celon .l Plumairo. — Nidifi-
cation in Relation to Color. — Lobs of Nuptial Plumage during tho
Winter 147

CHAPTER XVI.

birds — concluded. .

The Immature Plumage in Relation to the Character of tho Plumage in
both Sexes when Adult. — Six Classes of Cases. — Sexual Differences
between the Males of Closely-allied or Representative Species. — The
Female assuming the Characters of tho Male. — Plumage of tho Young
in Relation to the Summer and "Winter Plumage of tho Adults. — Ou
the Increase of Beauty in tho Birds of tho World. — Protective Color-
ing.— Conspicuously-colored Birds. — Novelty appreeiated. — Summary
of the Four Cliapters on Birds ..... 175

CHAPTER XVU,

SECONDARY SEXUAL CHARACTERS OF MAMMALS.

The Law of Battle— Special Weapons, confined to tho Males. — Cause of
Absence of Weapons in the Female. — Weapons common to both
Sexes, yet primarily acquired by the Male. — Other Uses of such Weap-
ons.— Their High Importance. — Greater Sixe of the Male. — Means of
Defence.— On tho Preference shown by either Sex in the Pairing of
Quadrupeds ....... 228

CHAPTER XVin.

SECOND ART 8EXCAL CHARACTERS Of MAMMALS — COtUin Ufd.

Voice. — Remarkable Sexual Peculiarities in Seals. — Odor. — Development
of 'the Hair.— Color of the Hair and Skin.— Anomalous Case of the
Female being more ornamented than the Male. — Color and Ornaments
due to Sexual Selection. — Color acquired for tho Sake of Protection. —
Color, though common to both Sexes, often due to Sexual Selection. —

CONTENTS.

v

On the Disappearance of Spots and Stripes in Adult Quadrupeds. —
On the Colors and Ornaments of the Quadrumana. — Summary p. 261

CHAPTEK XIX.

SECONDARY SEXUAL CHARACTERS OP MAN.

Differences "between Man and "Woman. — Causes of such Differences and of
Certain Characters common to both Sexes. — Law of Battle. — Differ-
ences 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 . . . . 301

CHAPTER XX.

SECONDARY SEXUAL CHARACTERS OF MAN — Continued-

On the Effects of the Continued Selection of "Women according to a
Different Standard of Beauty in each Race. — On the Causes which
interfere with Sexual Selection in Civilized and Sayags Nations. —
Conditions favorable to Sexual Selection during Primeval Times. — On
the Manner of Action of Sexual Selection with Mankind.— On tho
"Women in Savage Tribes having some Power to chooso their Hus-
bands.— Absence of Hair on the Body, and Development of the Beard.
— Color of the Skin.— Summary ..... 339

CHAPTER XXL

GKNKHAL SUMMARY AND CONCLUSION.

Main Conclusion that Mania descended from BOme Lower Form. — Man-
ner of Development. — Genealogy of Man.— Intellectual and Moral
Faculties. — Scxuul Selection. — Concluding Remarks . . 808

POSTSCBIP T.

Vol. I., pp. 287-289. — I have fallen into a serious and
unfortunate error, in relation to the sexual differences of
animals, in attempting to explain what seemed to me a
singular coincidence in the late period of life at which
the necessary variations have arisen in many cases, and
the late period at which sexual selection acts. The ex-
planation given is wholly erroneous, as I have discovered
by working out an illustration in figures. Moreover, the
supposed coincidence of period is far from general, and
is not remarkable ; for, as I have elsewhere attempted
to show, variations arising early in life have often been
accumulated' through sexual selection, being then com-
monly transmitted to both sexes. On the other hand,
variations arising late in life cannot fail to coincide ap-
proximately in period with that of the process of sexual
selection.

SEXUAL SELECTION".

CHAPTER XII.

Secondary Sextjal Characters of Fishes, Amphibi-
ans, and Reptiles.

FisSes : Courtship and Battles of the Males. — Larger Size of the Females. —
Males, Bright Colors and Ornamental Appendages ; other Strange
Characters. — Colors and Appendages acquired by the Males during the
Breeding-season alone. — Fishes with both Sexes brilliantly colored. —
Protective Colors. — The less Conspicuous Cojors of the Female cannot
be accounted for on the Principle of Protection. — Male Fishes building
Nests, and taking Charge of the Ova and Young. Amphibians : Differ-
ences in Structure and Color between the Sexes. — Vocal Organs. Rep-
tiles : Chelonians. — Crocodiles. — Snakes, Colors in some Cases pro-
tective.— Lizards, Battles of. — Ornamental Appendages. — Strange Dif-
ferences in Structure between the Sexes. — Colors. — Sexual Ditlerenees
almost as great as with Birds.

We have now arrived at the great sub-kingdom bf the
Vertebrata, and will commence with the lowest class,
namely, Fishes. The males of Plagiostomous fishes
(sharks, rays) and of Chinueroid lishes are provided with
claspers which serve to retain the female, like the various
Structures possessed by so many of the lower animals.
Besides the claspers, the males of many rays have clus-
ters 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 somo species,
which have the other parts of their bodies smooth. They

2 SEXUAL SELECTION. [Part II.

are only temporarily developed during the breeding-sea-
son ; and Dr. Gtlnther suspects that they are brought into
action as prehensile organs by the doubling inward and
downward of the two sides of the body. It is a remark-
able fact that the females and not the males of some spe-
cies, as of Raid clavata, have their backs studded with
large hook-formed spines.1

Owing to the element which fishes inhabit, little is
known about their courtship, and not much about their
battles. The male stickleback ( Gasterosteus leiurus) has
been described as " mad with delight " when the female
comes out of her hiding-place and surveys the nest which
he has made for her. " He darts round her in every
direction, then to his accumulated materials for the nest,
then back again in an instant ; and as she does not ad-
vance he endeavors to push her with his snout, and then
tries to pull her by the tail and side-spine to the nest." a
The males are said to be polygamists ; 8 they are extraor-
dinarily bold and pugnacious, while "the females are
quite pacific." Their battles are at times desperate ; " for
these puny combatants fasten tight on each other for sev-
eral seconds, tumbling over and over again, until their
strength appears completely exhausted." With the
rough-tailed stickleback (G. trachurus) the males while
fighting swim round and round each other, biting and en-
deavoring 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

1 Yarrell, 'Hist, of British Fishes,' vol. ii. 1836, pp. 417, 425, 436.
Dr. Giinther informs me that the spines in R. clavata arc peculiar to the
female.

* See Mr. R. Warington's interesting articles in 1 Annals and Mag. of
Nat. Hist.' Oct. 1852 and Nov. 1855.

• Noel Humphreys, 'River Gardens,' 1857.

4 Loudon's * Mag. of Natural History,' vol. iii. 1830, p. 831.

Chap. XII.J

FISHES.

3

with such fatal effect, that I have seen one during a bat-
tle absolutely rip his opponent quite open, so that he sank
to the bottom and died." When a fish is conquered, "his
gallant bearing forsakes him ; his gay colors fade away ;
and he hides his disgrace among his peaceable compan-
ions, but is for some time the constant object of his con-
queror's persecution."

The male salmon^s as pugnacious as the little stickle-
back ; and so is the male trout, as I hear from Dr. Gtin-
ther. Mr. Shaw saw a violent contest between two male
salmons 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 while 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." 5 The keeper of the Stor-
montfield breeding-ponds visited, as Mr. Buist informs me,
in June, 1868, 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
color, " the lower jaw elongates, and a cartilaginous pro-
jection turns upward from the point, which, when the
jaws arc closed, occupies a deep cavity between " the in-
termaxillary bones of the upper jaw." 0 (Figs. 20 and

8 'The Field,' Juno 29, 1807. For Mr. Shaw's statement, Bee 1 l-Min-
burgh Review,' l k i :j. Another experienced observer (Sorope'a 1 Days <>t'
Salmon Fishing,' p. CO) remarks that the male worn1.!, ,1 lie <>"M, keep,
like the Btag, all other males away,

• Yarrell, « History oflJritisli Fishes,' vol. ii. ls:;r,, p. 10,

4

SEXUAL SELECTION.

[Pakt II.

27.) In our salmon this change of structure lasts only
during the breeding-season ; but in the Salmo lycaodon
of Northwestern America the change, as Mr J. K. Lord 7

Fig. 26.— Head of male of common salmon (Salmo salar) during the breeding-

season.

[This drawing, as well aa all the others in the present chapter, have been ex-
ecuted by the well-known artist, Mr. Q. Ford, under the kind superintendence
of Dr. Gunther, from specimens in the British Museum].

7 'The Naturalist in Vancouver's Island,' vol. i. 1866, p. 54.

Chap. XII.]

FISHES.

5

believes, is permanent and best marked in the older males
which have previously ascended the rivers. In these old
males the jaws become developed into immense hook-like

Fig. 27.— Head of female salmon.

projections, and 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 protect the jaw s, when
8 4 Scandinavian Adventures,' vol. i. 185-1, |>p. lol, 101.

6

SEXUAL SELECTION.

[Part II.

one inali' diaries another with wonderful violence ; but
the greatly developed teeth of the male American salmon
may be compared with the tusks of many male mf*"TO«rtp^
ami they indicate an offensive rather than a protective
purpose.

The salmon is not the only fish in which the teeth
differ in the two sexes. This is the case witli many rajs.
In the thornback (Raia clavata) the adult male has sharp,
pointed teeth, directed backward, while those of the fe-
male are broad aiyl flat, forming a pavement; so that
these teeth differ in the two sexes of the same species
more than is usual in distinct genera of the same family.
The teeth of the male become sharp only when he is
adult : while young they are broad and flat like those of
the female. As so frequently occurs with secondary sex-
ual characters, both sexes of some species of rays, for in-
stance II* batis, possess, when adult, sharp, pointed teeth ;
and here a character, proper to and primarily gained by
the male, appears to have been transmitted to the off-
spring of both sexes. The teeth are likewise pointed in
both sexes of It. macnkUa, but only when completely
adult ; the males acquiring them at an earlier age than the
females. We shall hereafter meet with analogous cases
with certain birds, in which the male acquires the plu-
mage common to both adult sexes, at a somewhat earlier
age than the female. With other species of rays the
males even when old never possess sharp teeth, and con-
sequently both sexes when adult are provided with broad,
flat teeth, like those of the young, and of the mature fe-
males of the above-mentioned species.* As the rays are
bold, strong, and voracious fishes, we may suspect that the
males require their sharp teeth for fighting with their
rivals; but as they possess many parts modified and

• See Yarrcll's account of the Rays in his • Hist of British Fishes,'
▼oL U. 1836, p. 416, with an excellent figure, and pp. 422, 432.

Chap. XII.]

FISHES.

7

adapted for the prehension of the female, it is possible
that their teeth may be used for this purpose.

In regard to size, M. Carbonnier 10 maintains that with
almost all fishes the female 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 the
female. As with many kinds of fishes, the males habitu-
ally fight together ; it is surprising that th^y have not
generally become through the effects of sexual selection
larger and stronger than the females. The males suffer
from their small size, for according to M. Carbonnier they
are liable to be devoured by the females of their own spe-
cies when carnivorous, and no doubt by other species.
Increased size must be in some manner of more impor-
tance 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 colors; or these arc much brighter in the male
than in 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-feat hers
to the peacock. I am indebted for most of the following
facts to the great kindness of Dr. (iunther. There is rea-
son to suspect that many tropical lishes differ sexually in
color and structure; and there are some striking oases
with our British fishes. The male Callionymus Jyra has
been palled "the gemmeous dragoiiet " from its brilliant,
gem-like colors." Whenfreshly taken from tin' sea the
body is yellow of various shades, striped and Bpotted with
vivid blue on the head; the dorsal lins are pale brown

with dark longitudinal hands; the ventral, caudal, and
anal lins being bluish-black. The female, or sordid drag*

• 10 As quoted in 'The luinurr,' |Nt',M, \> ".i'.'.i.

8 SEXUAL SELECTION. [Part II.

onet, was considered by Linnaeus and by many subse-
quent naturalists as a distinct species; it is of a dingy

Fig. 28.— Callionymns lyra. Upper figure, male ; lower figure, female.

reddish-brown, with the dorsal fin brown and the other
fins white. The* sexes differ also in the proportional size
of the head and mouth, and in the position of the eyes ; 11
but the most striking difference is the extraordinary elon-
gation in the male (Fig. 28) of the dorsal fin. The young
males resemble, in structure and color, the adult females.
Throughout the genus Callionymus,13 the male is gener-

11 I have drawn up this description from YarrelTs 'British Fishes,'
vol. i. 1836, pp. 261, 266.

18 1 Catalogue of Acanth. Fishes in the British Museum,' by Dr.
Giinther, 1861, pp. 138-151.

Chap. XII.]

FISHES.

9

ally much more brightly spotted than the female, and in
several species, not only the dorsal, but the anal fin of the
male, is much elongated.

The male of the Cottus scorpius, or sea-scorpion, is
more slender antl smaller than the female. There is also
a great difference in color between them. It is difficult,
as Mr. Lloyd 13 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 colors
with which it, in other respects so ill-favored, is at that
time adorned." Both sexes of the Ldbrus rnixtus, al-
though very different in color, are beautiful ; the male
being orange with bright-blue stripes, and the female
bright-red with some black spots on the back.

In the very distinct family of the Cyprinodontidge —
inhabitants of the fresh waters of foreign lands — the sexes
sometimes differ much in various characters. In the male
v of the Mollienesia petenensis,1* the dorsal fin is greatly
developed, and is marked with a row of large, round, ocel-
lated, bright-colored spots ; while the same fin in the fe-
male 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-
colored. In the male of an allied form, the Xiphophorus
Hellerii (Fig. 29), the inferior margin of the anal fin is
developed into a long filament, which is striped, as I hear
from Dr. Gllnther,with bright colors. This filament does
not contain any muscles, and apparently cannot be of any
direct use to the fish. As in the case of the CMKonymus,
the males while young resemble in color and structure (he
adult females. Sexual differences such as these may be

18 1 Game IVirds of Sweden,' etc., 1807, p. 400.

14 With respect to this and (lie following species I am indebted to Dr.
Giinthcr for information; sec also his paper on the Fishes of Central
America, in 'Transact. Zoolog. Soc.' vol. vi. lNt;s( p. I S5.

10 SEXUAL SELECTION [Part EC

strictly compared with those which are so frequent with
gallinaceous birds.16

Pio. 29.— Xiptaophorus Hellerii. Upper figure, male; lower figure, female.

In a siluroid fish, inhabiting the fresh waters of South
America, namely the Pltcostomus barbatus " (Fig. 30),
the male has its mouth and interoperculum fringed with a
beard of stiff hairs, of which the female shows hardly a
trace. These hairs are of the nature of scales. In another
species of the same genus, soft flexible tentacles project
from the front part of the head of the male, which are
absent in the female. These tentacles are prolongations
of the true skin, and therefore are not homologous with
the stiff hairs of the former species ; but it can hardly be
doubted that both serve the same purpose. What this
purpose may be it is difficult to conjecture ; ornament
does not here seem probable, but we can hardly suppose

15 Dr. Gunther makes this remark : ' Catalogue of Fishes in the Brit-
ish Museum,' vol. iii. 1861, p. 141.

M See Dr. Gunther on this genus, in 'Proc. Zoolog. Soc.' 1868, p. 232.

Chap. XII.] FISHES. . H

12

SEXUAL SELECTION.

[Part II.

that stiff hairs and flexible filaments can be useful in any-
ordinary way to the males alone. The Monacanthus
scopas, which was shown to me in the British Museum by
Dr. Giinther, presents a nearly analogous case. The male
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 an inch and a half in length ; the female
has on the same place a cluster of bristles, which may be
compared with those of a tooth-brush. In another species,
the M. peronii, the male has a brush like that possessed
by the female of the last species, while the sides of the
tail in the female are smooth. In some other species the
same part of the tail can be perceived to be a little rough-
ened in the male and perfectly smooth in the female ; and
lastly, in others, both sexes have smooth sides. In that
strange monster, the Chimcera monstrosa, the male has a
hook-shaped bone on the top of the head, directed for-
ward, with its rounded end covered with sharp spines ; in
the female " this crown is altogether absent," but what its
use may be is utterly unknown.17

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 18 a crest is developed
on the head of the male only during the breeding-season,
and their bodies at the same time become more brightly-
colored. There can be little doubt that this crest serves
as a temporary sexual ornament, for the female does not
exhibit a trace of it. In other species of the same genus
both sexes possess a crest, and in at least one species
neither sex is thus provided. In this case and in that of
the Monacanthus, we have good instances to how great
an extent the sexual characters of closely-allied forms may

17 F. Buckland, in 'Land and Water/ July, 1868, p. 377, with a
figure.

18 Dr. Giinther, 'Catalogue of Fishes,' vol. hi. pp. 221, 240.

Chap. XII.J

FISHES.

13

differ. In many of the Chromidae, for instance, in Geo-
phagus and especially in Cichla, the males, as I hear from
Prof. Agassiz,19 have a conspicuous protuberance on the
forehead, which is wholly wanting in the females and in
the young males. Prof. Agassiz adds : " I have often
observed these fishes at the time of spawning when the
protuberance is largest, and at other seasons when it is
totally wanting and the two sexes show 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 Amazons know nothing about its use."
These protuberances in their periodical appearance resem-
ble the fleshy caruncles on the heads of certain birds ;
but whether they serve as ornaments must remain at
present doubtful.

The males of those fishes, which differ permanently in
color from the females, often become more brilliant, as I
hear from Prof. Agassiz and Dr. Gunther, during the
breeding-season. This is likewise the case with a multi-
tude of fishes, the sexes of which at all other seasons of
the year are identical in color. The tench, roach, and
perch, may be given as instances. The male salmon at
this season is " marked on the cheeks witli orange-colored
stripes, which gave it the appearance of a Labrus, and
the body partakes of a golden-orange tinge. The females
are dark in color, and are commonly called blacktish." 30
An analogous and even greater change takes place with
the tfalmo eriox, or bull-trout ; the males of the char (S.
umbla) arc likewise at this season rather brighter in
color than the females.31 The colors of the pike (Esox re-

19 Sec also 'A Journey in Brazil,' by Prof, and Mrs. Agassi/, IST.S,
p. 220.

90 Yarrcll, 'British Fishes,' vol. ii. is:!)',, pp. 10, 12, :tr..
" W. Thompson, in ' Annals and Ma^. of Nat. History,' vol. \ i. ISM,
p. 440.

14

SEXUAL SELECTION.

[Part II.

tieulatus), 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 ( Gasterosteus
leiurus), 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 trans-
lucent, and glowed with an internal incandescence."
After the breeding-season these colors all change, the
throat and belly become of a paler red, the back more
green, and the glowing tints subside.

That with fishes there exists some close relation be-
tween their colors and their sexual functions we can clearly
see — firstly, from the adult males of certain species being
differently colored from the females, and often much more
brilliantly; secondly, from the same males, while im-
mature, resembling the mature females ; and, lastly, from
the males, even of those species which at all other times
of the year are identical in color with the females, often
acquiring brilliant tints during the spawning-season. We
know that the males are ardent in their courtship, and
sometimes fight desperately together. If we may assume
that the females have the power of exerting a choice and
of selecting the more highly-ornamented males, all the
above facts become intelligible through the principle of
sexual selection. On the other hand, if the females ha-
bitually deposited and left their ova to be fertilized by the
first male whicli chanced to approach, this fact would be

w 'The American Agriculturist,' 1868, p. 100.
n 1 Annals and Mag.' of Nat. Hist.' Oct. 1852.

Chap XII.] FISHES. 15

•

fatal to the efficiency of sexual selection ; for there could
be no choice of a partner. But, as far as is known, the
female never willingly spawns except in the close presence
of a male, and the male never fertilizes the ova except in
the close presence of a female. It is obviously difficult to
obtain direct evidence with respect to female fishes select-
ing their partners. An excellent observe^24 who carefully
watched the spawning of minnows (Cyprinus phoxinus)9
remarks that owing to the males, which were ten times as
numerous as the females, crowding closely round them, he
could " speak only doubtfully on their operations. When
a female came among a number of males they immediately
pursued her ; if she was not ready for shedding her spawn,
she made a precipitate retreat ; but if she was ready, she
came boldly in among them, and was immediately pressed
closely by a male on each side ; and when they had been
in that situation a short time, were superseded by other
two, who wedged themselves in between them and the
female, who appeared to treat all her lovers with the same
kindness." Notwithstanding this last statement, I can-
not, from the several previous considerations, give up the
belief that the males which are the most attractive to the
females, from their brighter colors or other ornaments,
are commonly preferred by them ; and that the males have
thus been rendered more beautiful in the course of ages.

We have next to inquire whether tliis view can be ex-
tended, through the law of the equal transmission of char-
acters to both sexes, 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 (£. pavo), described," with

M Loudon's 'Mag. of Nat. Hist.' vol. v. 1832, p. 081.
••Bory <lc Saint-Vincent, in 'Dirt. Class. cl'Hist. Nat.' torn. i\. ISJrt,
p. 151.

L6 SEXUAL SELECTION. [Part II.

•

pardonable exaggeration, as formed of polished scales of
gold encrusting lapis-lazuli, rubies, sapphires, emeralds,
and amethysts, we may, with much probability, accept
this belief; for we have seen that the sexes in at least one
species differ greatly in color. With some fishes, as with
many of the lowest animals, splendid colors may be the
direct result of the nature of their tissues, and of the sur-
rounding conditions, without any aid from selection. The
gold-fish {^Cy primus 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 colors to a single
abrupt variation, due to the conditions to which this fish
has been subjected under confinement. It is, however,
more probable that these colors have been intensified
through artificial selection, as this species has been care-
fully bred in China from a remote period.28 Under nat-
ural conditions it does not seem probable that beings so
highly organized as fishes, and which live under such com-
plex relations, should become brilliantly colored without
suffering some evil, or receiving some benefit, from so
great a change, and consequently without the intervention
of natural selection.

What, then, must we conclude in regard to the many
fishes, both sexes of which are splendidly colored ? Mr.
Wallace 37 believes that the species which frequent reefs,

86 Owing to some remarks on this subject, made in my work 1 On the
Variation of Animals under Domestication,' Mr. W. F. Mayers (' Chinese
Notes and Queries,' Aug. 1868, p. 123) has searched the ancient Chinese
encyclopaedias. He finds that gold-fish were first reared in confinement
during the Sung Dynasty, which commenced a. d. 960. In the year 1129
these fishes abounded. In another place it is said that since the year
1548 there has been "produced at Hang-Chow a variety called the fire-
fish, from its intensely red color. It is universally admired, and there is
not a household where it is not cultivated, in rivalry as to Us color, and
as a source of profit."

" 'Westminster Review,' July, 1867, p. 7.

Chap. XII.]

FISHES.

17

where corals and other brightly-colored organisms abound,
are brightly colored 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-colored corals or other or-
ganisms for the fishes to resemble ; yet many species in
the Amazons are beautifully colored, and many of the car-
nivorous Cyprinidse in India are ornamented with " bright
longitudinal lines of various tints." 28 Mr. McClelland; in
describing these 'fishes goes so far as to suppose that the
peculiar brilliancy of their colors " serves as " a better
mark for king-fishers, terns, and other birds which are
destined to keep the number of these fishes in check ; "
but at the present day few naturalists will admit that any
animal has been made conspicuous as an aid to its own
destruction. It is possible that certain fishes may have
been rendered conspicuous in order to warn birds and
beasts of prey (as explained when treating of caterpillars)
that they were unpalatable ; but it is not, I believe,
known that any fish, at least any fresh-water fish, is re-
jected 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 colored, is that
their colors have been acquired hj the males as a sexual
ornament, and have been transferred in an equal or nearly
equal degree to the other sex.

We have now to consider whether, when the male dif-
fers in a marked manner from the female in color or in
other ornaments, he alone has been modified, with the
variations inherited only by his male offspring; or whether
the female has been specially modified and rendered incon-
spicuous for the sake, of protection, such modifications be-
ing inherited only by the females. It is impossible to

88 "Indian Cyprinidoe," by Mr. J. McClrllaml, 4 Asiatic Ucseiinlws,'
vol. xix. part ii. L889, p. 230.

18

SEXUAL SELECTION.

[Part II.

doubt that color has been acquired by many fishes as a
protection : no one can behold the speckled upper surface
of a flounder, and overlook its resemblance to the sandy
bed of the sea on which it lives. One of the most striking
instances ever recorded of an animal gaining protection
by its color (as far as can be judged in preserved speci-
mens) and by its form, is that given by Dr. Gtlnther 29 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. Fishes offer valuable evi-
dence on this head. We can see that one sex will not be
modified through natural selection for the sake of protec-
tion 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
sex; 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 of smaller size, 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 most conspicuously colored.
The ova are fertilized immediately after being deposited,
and when this process lasts for several days, as in the case
of the salmon,80 the female, during the whole time, is at-
tended by the male. After the' ova are fertilized they are,
in most cases, left unprotected by both parents, so that
the males and females, as far as ovipflsition is concerned,
are equally exposed to danger, and both are equally im-
portant for the production of fertile ova ; consequently
the more or less brightly-colored individuals of either sex
would be equally liable to be destroyed or preserved, and

» 'Proc. Zoolog. Soc.' 1865, p. 327, pis. xiv., xv.
80 Yarrell, 'British Fishes,' vol. ii. p. 11.

Chap. XII.]

FISHES.

19

both would have an equal influence on the colors of their
offspring or the race.

Certain fishes, belonging to several families, make
nests ; and some of these fishes take care of their young
when hatched. Both sexes of the brightly-colored Creni-
labrus massa and melops work together in building their
nests with sea-weed, shells, etc.31 But the males of cer-
tain fishes do all the work, and afterward take exclusive
charge of the young. This is the case with the dull-col-
ored gobies,32 in which the sexes are not known to differ
in color, and likewise with the sticklebacks (Gasterosteus),
in which the males become brilliantly colored during the
spawning-season. The male of the smooth-tailed stickle-
back ( G. leiurus) performs during a long time the duties
of a nurse with exemplary care and vigilance, and is con-
tinually 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 spe-
cies. . It would indeed be no small relief to the male if
the female, after depositing her egj^s, were immediately
devoured by some enemy, for he is forced incessantly to
drive her from the nest.33

The males of certain other fishes inhabiting South
America and Ceylon, and belonging to two distinct or-
ders, have the extraordinary habit of hatching the eggs
laid by the females within their mouths or branchial cavi-
ties."4 With the Amazonian species which follow this
habit, the males, as I am informed by the kindness of

81 According to the observations of M. Gerbc; see Giinthcr's 'Record
of Zoolog. Literature,' 18C5, p. 194.

82 Cnvicr, 4 Regno Animal,' vol. ii. IRL'i), p. 242.

83 See Mr. Waringtou's most interesting description of the habits of
the Oaslcroslcm hi urns, in 'Annals and Mag. of Nat. Hist.' Nov. ls;.;>.

84 Prof. Wyman, in ' Proo. Boston Sue of Nat. Hist.' Sept. L5, is;>7.
Also, W. Turner, in 'Journal of Anatomy and Phys.' Nov. l, L866, p. 78.
Dr. Gttnther has likewise described other eases.

20

SEXUAL SELECTION.

[Part IL

Prof. Agassiz, " not only are generally brighter than the
females, but the difterence is greater at the spawning-sea-
son than at any other time." The species of Geophagus
act in the same manner ; and in this genus, a conspicuous
protuberance becomes developed on the forehead of the
males during the breeding-season. With the various spe-
cies of Chromids, as Prof. Agassiz likewise informs me,
sexual differences in color 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 Promotis does. It ought also to be
observed that these sitters are among the brightest spe-
cies in their respective families ; for instance, Hygrogonus
is bright green, with large black ocelli, encircled with the
most brilliant red." Whether with all the species of
Chromids it is the male alone which sits on the eggs is
not known. It is, however, manifest that the fact of the
eggs being protected or unprotected, has had little or no
influence on the differences in color between the sexes.
It is further manifestpn all the cases in which the males
take exclusive charge of the nests and young, that the
destruction of the brighter-colored males would be far
more influential on the character of the race, than the de-
struction of the brighter-colored females ; for the death
of the male during the period of incubation or nursing
would entail the death of the young, so that these could
not inherit his peculiarities ; yet, in many of these very cases
tlfe males are more conspicuously colored than the females.

In most of the Lophobranchii (Pipe-fish, Hippocampi,
etc.) the males have cither marsupial sacks or hemispheri-
cal depressions on the abdomen, in which the ova laid by
the female are hatched. The males also show great .at-
tachment to their young." The sexes do not commonly
85 Yarrell, 4 Ilist. of British Fishes,' voL ii. 1836, pp. 829, 888.

Chap. XII.]

FISHES.

21

differ much in color ; but Dr. Gunther believes that the
male Hippocampi are rather brighter than the females.
The genus Solenostoma, however, offers a very curious ex-
ceptional case,36 for the female is much more vividly col-
ored and spotted than the male, and she alone has a mar-
supial 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 colored than the male. It is improb-
able 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 colored than the fe-
males, and as here the female Solenostoma takes the same
charge and is brighter than the male, it might be argued
that the conspicuous colors of the sex which is the most
important of the two for the welfare of the offspring must
serve, in some mauner, as a protection. But from the
multitude of fishes, the males of which are either perma-
nently or periodically brighter than the* females, but
whose life is not at all more important than that of the
female for the welfare of the species, this view can hardly
be maintained. When we treat of birds we shall meet
with analogous cases in which 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 explana-
tion, namely, that the males have selected the more at-
tractive females, instead of the latter having selected, in
accordance with the usual rule throughout the animal
kingdom, the more attractive males.

On the whole, we may conclude that, with most fishes,
in which the sexes differ in color or in other ornamental

M Dr. Giinthcr, sineo publishing un account of this species in ' The
Fishes of Zanzibar,' by Colonel Play fair, lKCC, p. l.'tT, has rccxamincil
the specimens, and bus given me the above information.

22

SEXUAL SELECTION.

[Part II.

characters, the males originally varied, with their varia-
tions transmitted to the same Sex, and accumulated
through sexual selection hy attracting or exciting the fe-
males. In many cases, however, such characters have
been transferred, either partially or completely, to the
females. In other cases, again, both sexes have been col-
ored alike for the sake of protection ; but in no instance
does it appear that the female alone has had her colors or
other characters specially modified for this purpose.

The last point which need be noticed is that in many
parts of the world fishes are known to make peculiar
noises, which are described in some cases as being musi-
cal. Very little has been ascertained with respect to the
means by which such sounds are produced, and even less
about their purpose. The drumming of the Umbrinas in
the European seas is said to be audible from a depth of
twenty fathoms. The fishermen of Rochelle assert " that
the males alone make the noise during the spawning-time ;
and that it is possible, by imitating it, to take them with-
out bait." '7 'If this statement is trustworthy, we have BO
instance in this, the lowest class of the Vertebrata, of
what we shall find prevailing throughout the other verte-
brate classes, and which prevails, as we have already seen,
with insects and spiders ; namely, that vocal and instru-
mental sounds so commonly serve as a love-call or as a
love-charm, that the power of producing them was proba-
bly first developed in connection with the propagation of
the species.

Amphibians.

Urodela. — First for the tailed amphibians. The sexes
of salamanders or newts often differ much both in color
and structure. In some species prehensile claws are de-
veloped on the fore-legs of the males during the breeding-

* The Rev. C. Kingsley, in 4 Nature,' May, 1870, p. 40.

Chap. XII.]

AMPHIBIANS.

23

season ; and at this season in the male Triton palmipes
the hind-feet are provided with a swimming web, which is
almost completely absorbed during the winter; so that
their feet then resemble those of the female.38 This struct-

Fig. 31.— Triton cristatns (half natural size, from Bell's 'British Reptiles').
Upper figure, male during the hreeding-season ; lower figure, female.

ure no doubt aids the male in his eager search and pursuit
of the female. With our common newts (Triton puno
tatus and cristatus) a deep, much indented crest is devel-
oped along the back and tail of the male during the breed-
ing-season, being absorbed during the winter. It is not
furnished, as Mr. St. George Mivart informs me, with
muscles, and therefore cannot be used for locomotion.
As during the season of courtship it becomes edged with
bright colors, it serves, there can hardly be a doubt, as :i
masculine ornament. In many species the body promts
strongly-contrasted though lurid tints; and these become
more vivid during the breeding-season. The male, lor
instance, of our common little newt (Triton />inift<tt us) is
" brownish gray above, passing into yellow beneath, which

"Bell, "History of Uritiah Reptiles," '2d edit. is in, pp. I .v. l.v.i

24

SEXUAL SELECTION.

[Part II.

in the spring becomes a rich bright orange, marked every-
where 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 color with scattered brown
dots ; and the lower surface is often quite plain." The
young are obscurely tinted. The ova are fertilized during
the act of deposition and are not subsequently tended by
either parent. We may therefore conclude that the males
acquired their strongly-marked colors and ornamental ap-
pendages through sexual selection; these being trans-
mitted either to the male offspring alone or to both sexes.

Anura or Batrachia. — With many frogs and toads
the colors evidently serve as a protection, such as the
bright-green tints of tree-frogs and the obscure mot-
tled shades of many terrestrial species. The most con-
spicuously-colored toad which I ever saw, namely, the
Phryniscus nigricans*0 had the whole upper surface of the
body as black as ink, with the soles of the feet and parts
of the abdomen spotted with the brightest vermilion. It
crawled about the bare sandy or open grassy plains of La
Plata under a scorching sun, and could not fail to catch
the eye of every passing creature. These colors may be
beneficial by making this toad known to all birds of prey
as a nauseous mouthful ; for it is familiar to every one
that these animals emit a poisonous secretion, which
causes the mouth of a dog to froth, as if attacked by hy-
drophobia. I was the more struck with the conspicuous
colors of this toad, as close by I found a lizard (Proctotre-
tus multhnacidatm) which, when frightened, flattened its
body, closed its eyes, and then from its mottled tints
could hardly be distinguishable from the surrounding
sand.

88 Bell, ibid. pp. 146, 151.

40 * Zoology of the Voyage of the " Beagle," 1 1843. " Reptiles," bv
Mr. Bell, p. 49.

Chap. XII.]

AMPHIBIANS.

25

With respect to sexual differences of color, Dr. Giin-
ther knows of no striking instance 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 Dr. Gunther know of any striking difference in ex-
ternal structure between the sexes, excepting the promi-
nences which become developed during the breeding-sea-
son on the front-legs of the male, by which he is enabled
to hold the female. The Megalophrys montana*1 (Fig.
32) offers the best case of a certain amount of structural
difference between the sexes ; for in the male the tip of the
nose and the eyelids are produced into triangular flaps of
skin, and there is a little black tubercle on the back —
characters which are absent, or only feebly developed, in
the females. It is surprising that frogs and toads should
not have acquired more strongly-marked sexual differ-
ences ; for, though cold-blooded, their passions are strong.
Dr. Gunther informs me that he has several times found
an unfortunate female toad dead and smothered from hav-
ing been so closely embraced by three or four males.

These animals, however, offer one interesting sexual
difference, namely, in the musical powers possessed by the
males ; but to speak of music, when applied to the discord-
ant 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 de
Janeiro I used often to sit in the evening to listen to a
number of little Hylae, which, perched on blades of grass
close to the water, sent forth sweet chirping notes in har-
mony. 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

*' 'The Reptiles of India,' by Dr. A. tiimther, Ka\ Sue. ISM, ,,. nil.
48 Boll, 'History of British Reptiles,' 1849, p. 98.
21

&6

SEXUAL SELECTION.

[Part II.

fact the vocal organs of the males are more highly de-
veloped than those of the females. In some genera the
males alone are provided with sacs which open into the
larynx.43 For instance, in the edible frog {liana esculen-
ta) " the sacs are peculiar to the males, and become, when
filled with air in the act of croaking, large globular blad-

Fig. 32.— Megalophrys raontana. The two left-hand figures, the male ; the two
right-hand figures, the female.

ders, standing out one on each side of the head, near the
corners of the mouth." The croak of the male is thus
rendered exceedingly powerful ; while that of the female
is only a slight groaning noise.44 The vocal organs differ
considerably in structure in the several genera of the
family ; and their development in all cases may be attrib-
uted to sexual selection.

Reptiles.

Chelonia, — Tortoises and turtles do not offer well-
marked sexual differences. In some species, the tail of

43 J. Bishop, in 'Todd's Cyclop, of Anat. and Phys.' vol. iv. p. 1503.

44 Bell, ibid. pp. 112-114.

Chap. XII.J

REPTILES.

27

the male is longer than that of the female. In some, the
plastron or lower surface of the shell of the male is slight-
ly concave in relation to the back of the female. The
male of the mud-turtle of the United States ( Chrysemys
picta) has claws on its front-feet twice as long as those
of the female ; and these are used when the sexes unite.46
With the huge tortoise of the Galapagos Islands (Testudo
nigra) the males are said to grow to a larger size than
the females : during the pairing-season, and at no other
time, the male utters a hoarse, bellowing noise, which can
be heard at the distance of more than a hundred yards ;
the female, on the other hand, never uses her voice.48

Crocodilia. — The sexes apparently do not differ in
color ; nor do I know that the males fight together,
though this is probable, for some kinds make a prodi
gious display before the females. Bartram47 describes the
male alligator as striving to win the female by splashing
and roaring in the midst of a lagoon, " swollen to an ex-
tent ready to burst, with his 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 sea-
son of love, a musky odor is emitted by the submaxillary
glands of the crocodile, and pervades their haunts.48

Ophidia. — I have little to say about Snakes. Dr.
Gtinther 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 color, Dr. Gtinther can almost al-
ways distinguish the male from the female by his more

46 Mr. C. J. Maynard, ' The American Naturalist,' Dec. 1869, p. 555.

46 See my 4 Journal of Researches during the Voyage of the " Bea-
gle,"' 1845, p. 384.

47 'Travels through Carolina,' etc., 1701, p. 128.

48 Owen, 1 Anatomy of Vertebrates,1 vol. i. 1869, p. 015.

^8

SEXUAL SELECTION.

[Part IL

strongly-pronounced tints ; thus the black zigzag band on
the back of the male English viper is more distinctly de-
fined than in the female. The difference is much plainer
in the Rattlesnakes of North America, the male of which,
as the keeper in the Zoological Gardens showed me, can
instantly be distinguished from the female by having more
lurid yellow about its whole body. In South Africa the
Bucephalus capensls presents an analogous difference, for
the female " is never so fully variegated with yellow on
the sides, as the male." 49 The male of the Indian Dipsas
cynodo?i, on the other hand, is blackish-brown, with the
belly partly black, while the female is reddish or yellowish-
olive with the belly either uniform yellowish or marbled
with black. In the Tragops dispar of the same country,
the male is bright green, and the female bronze-colored."
No doubt the colors of some snakes serve as a protection,
as 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 colors of many kinds, for instance
of the common English snake or viper, serve to conceal
them ; and this is still more doubtful with the many for-
eign species which are colored with extreme elegance.

During the breeding-season their anal scent-glands are
in active function ; 61 and so it is with the same glandH 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

49 Sir Andrew Smith, 'Zoolog. of South Africa: Reptilia,' 1849, pi. x.

60 Dr. A. Gunther, 'Reptiles of British India,' Ray Soc. 1864, pp. 304,
308.

61 Owen, 'Anatomy of Vertebrates,' vol. i. 1866, p. 615.

■ The celebrated botanist Schleiden incidentally remarks (' Uebei
den Darwinismus : Unsere Zeit,' 1869, s. 269), that Rattlesnakes use

Chap. XII.]

REPTILES.

29

appearing so sluggish, are amorous ; for many have been
observed crowding round the same female, and even round
the dead body of a female. They are not known to fight
together from rivalry. Their intellectual powers are high-
er than might have been anticipated. An excellent ob-
server in Ceylon, Mr. E. Layard,63 saw a Cobra thrust its
head through a narrow hole and swallow a toad. " With
this encumbrance he could not withdraw himself ; finding
this, he reluctantly disgorged the precious morsel, which
began to move off; this was too much for snake philoso-
phy 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
learned, and the toad was seized by one leg, withdrawn,
and then swallowed in triumph."

It does not, however, follow because snakes have some
reasoning power and strong passions, that they should
likewise be endowed witli sufficient taste to admire bril-
liant colors in their partners, so as to lead to the adorn-
ment of the species through sexual selection. Neverthe-
less, it is difficult to account in any other manner for the
extreme beauty of certain species ; for instance, of the
coral-snakes of South America, which are of a ricli 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
colored in this peculiar manner, as Mr. Wallace slates on
the authority of Dr. Gunther,54 are found nowhere else in

their rattles as a sexual call, by which the two sexes find each other. 1
do not know whether this suggestion rests on any direct observations.
These snakes pair in the Zoological Gardens, bul the keepers have ne\er
observed that they use their rattles at this season more than at any
other.

58 " Rambles in Ceylon," 'Annals and Mag. of Nat. Hist.' 2d scries
vol. ix. isr.'j, p. 383.

64 'Westminster Review,' July l, 1867, p. 82.

30

SEXUAL SELECTION.

[Part IL

the world except in South America, and here no less than
four genera occur. One of these, Elaps, is venomous ; a
second and widely-distinct genus is doubtfully venomous,
and the two others are quite harmless. The species be-
longing 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 colors as a protection, on the
principle of imitation; for they would naturally be
thought dangerous by their enemies. The cause, how-
ever, of the bright colors of the venomous Elaps remains
to be explained, and this may perhaps be sexual selection.

Lacertilia. — The males of some, probably of many
kinds of lizards, fight together from rivalry. Thus the
arboreal Anolis cristatellus of South 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, 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. Gtlnther has
been able to ascertain, is the general rule with lizards of
all kinds.

The sexes often differ greatly in various external char-
acters. The male of the above-mentioned Anolis is fur-

66 Mr. N. L. Austen kept these animals alive for a considerable time ;
see 1 Land and Water,' July, 1867, p. 9.

Chap. XII.]

REPTILES.

31

nished with a crest, which runs along the back and tail,
and can be erected at pleasure ; but of this crest the female
does not exhibit a trace. In the Indian Cophotis ceylanica,
the female possesses a dorsal crest, though much less de-
veloped than in the male ; and so it is, as Dr. Gtinther in-
forms 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. 33), which can be folded
up like a fan, and is colored blue, black, and red; but
these splendid colors are exhibited only during the pair-
ing-season. The female does not possess even a rudiment
of this appendage. In the Anolis cristatellus, according
to Mr. Austen, the throat-pouch, which is bright red mar-
bled with yellow, is present, though in a rudimental con-
dition, in the female. Again, in certain other lizards, both
sexes are equally well provided with throat-pouches. Here,
as in so many previous
cases, we see, with species
belonging to the same
group, the same character
confined to the males, or
more largely developed in
the males than in the fe-
males, or equally developed
in bol 1) sexes. The lill le

lizards of i lie genus I )raco,
which glide through the
air on their rib-supported
parachutes, and which in the beauty of their colors baffle

description, are furnished with skinny appendages to the
throat, 'like the wattles of gallinaceous birds." These he-
come erected when the animal is excited. They occur in
both HCXCS, but are best developed in the male when ar-

Fio. .13.— Sitana minor; "Male, witli the
gnlar pouch expanded (from (JUn-
ther'p 'Reptiles of India').

32

SEXUAL SELECTION.

[Part II.

rived at maturity, at which age the middle appendage is
sometimes twice as long as the head. Most of the species
likewise have a low crest running along the neck ; and this
is much more developed in the full-grown males than in
the females or young males.68

There are other and much more remarkable differences
between the sexes of certain lizards. The male of Cerato-
phora aspera bears on the extremity of his snout an
appendage half as long as the head. It is cylindrical,
covered with scales, flexible, and apparently capable of
erection : in the female it is quite rudimental. In a second
species of the same genus a terminal scale forms a minute
horn on the summit of the flexible appendage ; and in a
third species (C. Stoddartii, Fig. 34), the whole append-
age is converted into a horn,
which is usually of a white color,
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 lengt h,
but is of quite minute size in the
female and in the young. These
appendages, as Dr. Gtlnther lias
remarked to me, may be com-
pared with the combs of galli-
naceous birds, and apparently
serve as ornaments.

In the genus Chamadeon
we come to the climax of dif-
ference between the sexes. The upper part of the skull
of the male C. bifurcm (Fig. 35), an inhabitant of Mada-

M All these statements and quotations, in regard to Cophotis, Sitana,
and Draco, as well as the following facts in regard to Ccratophora, are
taken from Dr. Gunther's magnificent work on the 1 Reptiles of British
India,' Ray Soc. 1864, pp. 122, 130, 135.

Fig. $4.— Ceratophora Stoddartii.
Upper flpure, male ; lower
figure, female.

Chap. XII. ]

REPTILES.

33

gascar, is produced into two great, solid, bony projec-
tions, covered with scales like the rest of the head ; and
of this wonderful modification of structure the female ex-
hibits only a rudiment. Again, in Chamoeleon Owenii
(Fig. 36), from the West Coast of Africa, the male bears

Fia. 86.— Chamaleon bifurcus. Upper figure, male ; lower figure, female.

on his snout and forehead three curious horns, of which
the female lias not a trace. These horns consist of an ex-
crescence of 1 c covered with a smooth sheath, forming

part of the general integuments of (lie body, so that they
are identical in structure with those of a bull, goat, or

other sheal h-liorncd ruminant. Although lh»' three QOTOfl

34

SEXUAL SELECTION.

[Part EL

differ so much in appearance from the two great prolon-
gations of the skull in C. bifurcus, we can hardly doubt
that they serve the same general purpose in the economy
of these two animals. The first conjecture which will
occur to every one is that they are used by the males for
fighting together ; but Dr. Gtlnther, to whom I am in-
debted for the foregoing details, does not believe that
such peaceable creatures would ever become pugnacious.

Hence we are
driven to infer
that these almost
monstrous devia-
tions of structure
serve as mascu-
line ornaments.

With many
kinds of lizards,
the sexes differ
slightly in color,
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 previously-mentioned Cophotis and
with the Acanthodactylus capensis of South Africa.
In a Cordylus of the latter country, the male is either
much redder or greener than the female. In the Indian
Calotes nigrilabris there is a greater difference in color
between the sexes ; the lips also of the male are black,
while 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

Fig. 36.— Chamsek-on Ovrcnii. Upper figure, male
lower figure, female.

Chap. XII.]

REPTILES.

35

pale grayish-green without spots." 67 We have seen that
the males alone of Sitana possess a throat-pouch ; and this
is splendidly tinted with blue, black, and red. In the
Proctotretus tenuis of Chili the male alone is marked with
spots of blue, green, and coppery-red.58 I collected in
South America fourteen species of this genus, and though
I neglected to record the sexes, I observed that certain
individuals alone were marked with emerald-like green
spots, while others had orange-colored gorges ; and these
in both cases no doubt were the males.

In the foregoing species, the males are more brightly
colored than the females, but with many lizards both
sexes are colored in the same elegant or even magnificent
manner; and there is no reason to suppose that such con-
spicuous colors are protective. With some lizards, how-
ever, the green tints no doubt serve for concealment ; and
an instance has already been incidently given of one
species of Proctotretus which closely resembles the sand
on which it lives. On the whole we may conclude with
tolerable safety that the beautiful colors of many lizards,
as well as various appendages and other strange modi-
fications of structure, have been gained by the males
through sexual selection for the sake of ornament, and
have been transmitted either to their male offspring alone
or to both sexes. Sexual selection, indeed, seems to have
played almost as important a part with reptiles as with
birds. But the less conspicuous colors of the females in
comparison with those of the males cannot be accounted
for, as Mr. Wallace believes to be the case with birds, by
the exposure of the females to danger during incubation.

67 Bell, 'History of British Reptiles,' 2d edit. 1849, p. 40.

68 For Proctotretus Bee 'Zoology of the Voyage of the "Beagle:"
Reptile*,1 by Mr. Bell, p. 8. For the Lizards of South Afrieu, sir '/.ool-
ogy of South Africa : Reptiles,' by Sir Andrew Smith, pk M| 8i>.
For the Indian (alotes, see ' Reptiles of Uritish India,' h\ Dr. tliinther,
p. 14:;.

86

SEXUAL SELECTION.

[Pakt II.

CHAPTER XIII.

Secondary Sexual Characters of Birds.

Sexual Differences. — Law of Battle. — Special Weapons. — Vocal Organs.—
Instrumental Music. — Love-Antics and Dances.— Decorations, Perma-*
nent and Seasonal. — Double and Single Annual Moults. — Display of
Ornaments by the Males.

Secondary sexual characters are more diversified and
conspicuous in birds, though not perhaps entailing more
important changes of structure, than in any other class of
animals. I shall, therefore, treat the subject at consider-
able length. Male birds sometimes, though rarely, pos-
sess special weapons for fighting with each other. They
charm the females by vocal or instrumental music of the
most varied kinds. They are ornamented by all sorts of
combs, wattles, protuberances, horns, air-distended sacs,
topknots, 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 colored. 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 odor which we may suppose serves
to charm or excite the female ; for that excellent observ-
er, Mr. Ramsay,1 says of the Australian musk-duck (Bizv-
ura lobata) that " the smell which the male emits during
the summer months is confined to that sex, and in some
individuals is retained throughout the year ; I have never,
even in the breeding-season, shot a female which had any

1 'Ibis,' vol. iii. (new aeries) 1867, p. 414.

Chap. XIII.]

BIRDS.

37

smell of musk." So powerful is this odor during the pair-
ing-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 shown by our enjoyment of the singing of birds,
and by our women, both civilized and savage, decking
their heads with borrowed plumes, and using gems which
are hardly more brilliantly colored than the naked skin
and wattles of certain birds.

Before treating of the characters with which we are
here more particularly concerned, I may just allude to
certain differences between the sexes which apparently
depend on differences in their habits of life ; for such
cases, though common in the lower, are rare in the higher
classes. Two humming-birds belonging to the genus
Eustephanus, which inhabit the island of Juan Fernandez,
were long thought to be specifically distinct, but are now
known, as Mr. Gould informs me, to be the sexes of the
same species, and they differ slightly in the form of the
beak. In another genus of humming-birds (Grypus), the
beak of the male is serrated along the margin and hooked
at the extremity, thus differing much from that of the
female. In the curious Neomorpha of New Zealand,
there is a still wider difference in the form of the beak ;
and Mr. Gould has been informed that the male with his
"straight and stout beak" tears off the bark of trees, in
order that the female may feed on the uncovered larva-
with her weaker and more curved beak. Something of
the same kind may he observed with our goldfinch (Car-
duclix elegans), for I am assured by Mr. .1. .Tenner Weir

that the bird-catohers can distinguish the males bythefar

slightly longer beaks. The Hocks of males, :is an old and
trustworthy bird-catcher asserted, are commonly found

* (JouM, ' llaml-l>ool< to the llii.lt ill' Australia,' lst.:., vol. li. |». .is:;

38

SEXUAL SELECTION: BIRDS.

[Part II.

feeding on the seeds of the teazle (Dipsacus) which they
can reach with their elongated beaks, while the females
more commonly feed on the seeds of the betony or
Scrophularia. With a slight difference of this nature as
a foundation, we can see how the beaks of the two sexes
might be made to differ greatly through natural selection.
In all these cases, however, especially in that of the quar-
relsome humming-birds, it is possible that the differences
in the beaks may have been first acquired by the males in
relation to their battles, and afterward led to slightly
changed habits of life.

Law of Battle. — Almost all male birds are extremely
pugnacious, using their beaks, wings, and legs, for fighting
together. We see this every spring with our robins and
sparrows. The smallest of all birds, namely, the hum-
ming-bird, is one of the most quarrelsome. Mr. Gosse *
describes a battle, in which a pair of humming-birds
seized hold of each other's beaks, and whirled round and
round, till they almost fell to the ground ; and M. Montes
de Oca, in speaking of another genus, says that two males
rarely meet without a fierce aerial encounter : when kept
in cages "their fighting has mostly ended in the splitting
of the tongue of one of the two, which then surely dies
from being unable to feed." * With Waders, the males
of the common water-hen (Gallinula chloropus) "when
pairing, fight violently for the females : they stand nearly
upright in the water and strike with their feet." Two
were seen to be thus engaged- for halt* an hour, until one
got hold of the head of the other, which would have been
killed had not the observer interfered ; the female all the
time looking on as a quiet spectator.* The males of an allied

* Quoted by Mr. Gould, 4 Introduction to the Trochilidae,' 1861, p. 29.

* Gould, ibid. p. 62.

» W. Thompson, 4 Nat Hist, of Ireland : Birds,' vol. ii. 1850, p. 327.

Chap. XII1.J

LAW OF BATTLE.

39

bird {Gallicrex cristatus), as Mr. Blyth informs me, are
one-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 pur-
pose, for instance, the Bulbuls (Pycnonotus hcemorrhous)
which " fight with great spirit." 6

The polygamous Ruff {Machetes pugnax, Fig. 37) is
notorious for his extreme pugnacity ; and in the spring,
the males, which are considerably larger than the females,
congregate day after day at a particular spot, where the
females propose to lay their eggs. The fowlers discover
these spots by the turf being trampled somewhat bare.
Here they fight very much like game-cocks, seizing each
other with their beaks and striking with their wings. The
great ruff of feathers round the neck is then erected, and
according to Colonel Montagu " sweeps the ground as a
shield to defend the more tender parts ; " and this is the
only instance known to me in the case of birds, of any
structure serving as a shield. The ruff of feathers, how-
ever, from its varied and rich colors probably serves in chief
part as an ornament. Like most pugnacious birds, they
seem always ready to fight, and when closely confined
often kill each other; but Montagu observed that their
pugnacity becomes greater during the spring, when the
long feathers on their necks are fully developed ; and at
this period the least movement by any one bird provokes
a general battle.7 Of the pugnacity of web-footed birds,
two instances will suffice : in Guiana " bloody fights occur
<lnring the breeding-season between the males of the wild
musk-duck ( (Uiirhia mo»vhUn)\ and whore these lights
have occurred the river is covered for some distance with

'Jtrdon, ' Blrdi of India,' 1808, rol ii. p. 96

' Kaogillivray, ' Sift, Brit Birds,' rol i\. 1862, pp. 177-lsi.

40

SEXUAL SELECTION: BIRDS.

[Part II

feathers." 8 Birds which seem ill-adapted for fighting en-
gage in fierce conflicts ; thus with the pelican the stronger

1843, p. 31.

Chap. XIII.]

LAW OF BATTLE.

41

males drive away the weaker ones, snapping with their
huge beaks and giving heavy blows with their wings.
Male snipes fight together, " tugging and pushing each
other with their bills in the most curious manner imagi-
nable." Some few species are believed never to fight ; this
is the case, according to Audubon, with one of the wood-
peckers of the United States (Picus auratus), although
" the hens are followed by even half a dozen of their gay
suitors." 9

The males of many birds are larger than the females,
and this no doubt is an advantage to them in their bat-
tles with their rivals, and has been gained through sexual
selection. 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 Cinclo-
raraphus cruralis (allied to our pipits) are by measure-
ment actually twice as large as their respective females.10
With many other birds the females are larger than the
males ; and as formerly remarked, the explanation often
given, namely, that the females have most of the work in
feeding their young, will not suffice. In some few cases,
as we shall hereafter see, the females apparently have ac-
quired their greater size and strength for the sake of con-
quering other females and obtaining possession of the
males.

The males of many gallinaceous birds, especially of
the polygamous kinds, are furnished witli special weapons
for fighting with their rivals, namely spurs, which can he
used with fearful effect. It has been recorded by a trust-
worthy writer11 that in Derbyshire a kite struck at a

9 'Ornithological Biography,1 vol. i. p. I'.H. For pelicans and snipes,
sec vol. iii. pp. 381, 477.

10 (ioiild, 1 Iluml-book of Birds of Australia,' vol. i. p. -'•'•'> ; vol. li. p
S88.

11 Mr. Hewitt in tin; ' Poultry Hook by Top'tiiu-irr,' I *•'•<'., p. 137.

AS

SEXUAL SELECTION: BIRDS. [Part II.

garue-hen accompanied by her chickens, when the cock
rushed to the rescue and drove his spur right through the
eye and skull of the aggressor. The spur was with diffi-
culty drawn from the skull, and as the kite though dead
retained his grasp, the two birds were firmly locked to-
gether; but the cock when disentangled was very little
injured. The invincible courage of the game-cock is noto-
rious: a gentleman who long ago witnessed the following
brutal scene, told me that a bird had both its legs broke n
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 un-
daunted courage until he received his death-stroke. In
Ceylon a closely-allied and wild species, the GaUus Stan-
leyi, is known to fight desperately "in defence of his
seraglio," so that one of the combatants is frequently
found dead.13 An Indian partridge ( Ortygornis gularis),
the male of which is furnished with strong and sharp
spurs, is so quarrelsome, " that the scars of former fights
disfigure the breast of almost every bird you kill." 11

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
Blackcock (Tetrao urog alius and T. tetrix), which are
both polygamists, have regular appointed places, where
during many weeks they congregate in numbers to fight
together and to display their charms before the females.
M. W. Kowalevsky informs me that in Russia lie has seen
the snow all bloody on the arenas where the Capercailzie
have fought ; and the Blackcocks " make the feathers fly
in every direction," when several "engage in a battle
royal." The elder Brehm gives a curious account of the

" Layard, 'Annals and Mag. of Nat. Hist.' vol. xiv. 1854, p. 68.
u Jerdon, ' Birds of India,' vol. Hi. p. 674.

Chap. XIII.]

LAW OF BATTLE.

43

Balz, as the love-dance and love-song of the Blackcock is
called in Germany. The bird utters almost continuously
the most strange 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, some-
times in a circle, and presses the under part of his beak so
hard against the ground that the chin-feathers are rubbed
off. During these movements he beats his wings and
turns round and round. The more ardent he grows the
more lively he becomes, until at last the bird appears like
a frantic creature." At such times the blackcocks are so
absorbed that they become almost blind and deaf, but less
so than the capercailzie : hence bird after bird may be
shot on the same spot, or even caught by the hand.
After performing these antics the males begin to fight :
and the same blackcock, in order to prove his strength
over several antagonists, will visit in the course of one
morning several Balz-places, which remain the same dur-
ing successive years.14

The peacock with his long train appears more like a
dandy than a warrior, but he sometimes engages in fierce
contests : the Rev. W. Darwin Fox informs me that two
peacocks became so excited while fighting at some little
distance from Chester, that they flew over the whole city,
still fighting, 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 Pig. 51,
p. 90) has two or more on each leg; and oik* of the l>loo<l
pheasants (It/tiKjiit is rruc/ifi/s) lias hem seen with live

spurs. The spurs arc generally confined to the male, be*

14 Ikohm, 4 IlluBt. Thiorlobon,' 1807, B. iv. 8. 851. Some of the foro-
going stutomontH mo taken IVom I,. Novo", 'Tin- ( iumc-HinlH of Sweden,'
etc., 1807, p. 19.

SEXUAL SELECTION: BIRDS. [Part II.

ing represented by mere knobs or rudiments in the female ;
but the females of the Java peacock (Pavo muticus) and,
as I am informed by Mr. Blyth, of the small fire-backed
pheasant (Euplocamus erythropthalmm) 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 safely be considered as a masculine character,
though occasionally transferred in a greater or less degree
to the females. Like most other secondary sexual charac-
ters, the spurs are highly variable both in number and de-
velopment in the same species.

Various birds have spurs on their wings. But the
Egyptian goose ( Chenalopex uEgyptiacus) has only " bare
obtuse knobs," and these probably show us the first steps
by which true spurs have been developed in other allied
birds. In the spur-winged goose {Plectropterus gamben-
sis), the males have much larger spurs than the females ;
and they use them, as I am informed by Mr. Bartlett, in
fighting together, so t hat, in this case, the wing-spurs serve
as sexual weapons ; but according to Livingstone, they are
chiefly used in the defence of the young. The Palamedea
(Fig. 38) is armed with a pair of spurs on each wing ; and
these are such formidable weapons that a single blow has
driven a dog howling away. But it does not appear that
the spurs in this case, or in that of some of the spur-winged
rails, are larger in the male than in the female.10 In cer-
tain plovers, however, the wing- spurs must be considered
as a sexual character. Thus in the male of our common
peewit ( Vanellus cristatus) the tubercle on the shoulder

15 Jerdon, 'Birds of India:' on Ithaginis, vol. iii. p. 523; on Gallo-
perdix, p. 641.

16 For the Egyptian goose, see Macgillivray, 'British Birds,' vol. iv.
p. 639. For Plectropterus, ' Livingstone's Travels,' p. 254. For Pala-
medea, Brchm'8 ' Thierleben,' B. iv. s. 740. See also on this bird Azaraf
'Voyages dans l'Amerique m6rid.' torn. iv. 1809, pp. 179, 253.

Chap. XIII.] LAW OF BATTLE. 45

of the wing becomes more prominent during the breeding-
season, and the males are known to fight together. In

Pio. Palamedea cornnta (from Brehm), showing the doobta irtafl HpurH,

and tint lllnincnt on tin* IicihI.

46 SEXUAL SELECTION: BIRDS. [Part II.

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 JSbplopterus 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 a fatal
result. Thus also they drive away other enemies.17

The season of love is that of battle ; but the males of
some birds, as of the game-fowl and ruff, and even the
young males of the wild-turkey and grouse,18 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 {JEstrelda amandava)
fight together by placing three small cages in a row, with
a female in the middle ; after a little time the two males
are turned loose, and immediately a desperate battle en-
sues.19 When many males congregate at the same ap-
pointed spot and fight together, as in the case of grouse
and various other birds, they are generally attended by
the females,30 which afterward pair with the victorious

11 See, on our peewit, Mr. R. Carr in 1 Land and Water,' Aug. 8,
1868, p. 46. In regard to Lobivanellus, see Jerdon's 'Birds of India,'
vol. iii. p. 647, and Gould's 1 Hand-book of Birds of Australia,' vol. ii. p.
220. For the Hoplopterus, see Mr. Allen in the 'Ibis,' vol. v. 1863,
p. 166.

18 Audubon, ' Ornith. Biography,' vol. ii. p. 492 ; vol. L pp. 4-13.

19 Mr. Blyth, 'Land and Water,' 1867, p. 212.

20 Richardson, on Tetrao umbellus, 'Fauna Bor. Amer. : Birds,' 1831,
p. 343. L. Lloyd, 'Game-Birds of Sweden,' 1857, pp. 22, 79, on the
capercailzie and blackcock. Brehm, however, asserts (' Thierleben,'
etc., B. iv. s. 352) that in Germany the gray-hens do not generally attend
the Balzen of the blackcocks, but this is an exception to the common
rulo ; possibly the hens may lie hidden in the surrounding bushes, as is

Chap. XIII.]

LAW OF BATTLE.

47

combatants. But in some cases the pairing precedes in-
stead of succeeding the combat : thus, according to Audu-
bon,21 several males of the Virginian goat-sucker (Capri-
mulgus Virginianus) "court, in a highly-entertaining
manner, the female, and no sooner has she made her
choice, than her approved gives chase to all intruders,
and drives them beyond his dominions." Generally the
males try with all their power to drive away or kill their
rivals before they pair. It does not, however, appear that
the females invariably prefer the victorious males. I have
indeed been assured by M. W. Kowalevsky 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, common-
ly gains his desire ; but some of these battles are caused
by wandering males trying to distract the peace of an al-
ready mated pair.22

Even with the most pugnacious species it is probable
that the pairing does not depend exclusively on the mere
strength and courage of the male : for such males are gen-
erally decorated with various ornaments, which often
become more brilliant during the breeding-season, and
which are sedulously displayed before the females. The
males also endeavor to charm or excite their mates l>\
love-notes, songs, and antics; and the courtship is, in
many instances, a prolonged affair. Hence it is not prob-
able; that the females are indifferent to the charms of the
opposite sex, or that they are invariably compelled to

known to be the case with the gray-hens in Scandinavia, and with other
species in North America.

81 'Ornithological Biography,1 vol. ii. p. 275.

2a Brehm, ' Thierleben,' etc., B. Iv. 1867, i>. 990. Audubon, Mh-nith.
Biography,1 vol. ii. p. 492.

48

SEXUAL SELECTION: BIRDS.

[i ,.kt n.

yield to the victorious males. It is more probable that
the females are excited, either before or after the conflict,
by certain males, and thus unconsciously prefer them. In
the case of Tetrao umbellus, a good observer23 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 I
have never been able to find a maimed hero, and seldom
more than a broken feather." I shall have to recur to
this subject, but I may here add that with the Tetrao
cupido of the United States, about a score of males assem-
ble at a particular spot, and strutting about make the
whole air resound with their extraordinary noises. At
the first answer from a female, the males begin to fight
furiously, and the weaker give way ; but then, according
to Audubon, both the victors and vanquished search for
the female, so that the females must either then exert a
choice, or the battle must be renewed. So, again, with
one of the Field-starlings of the United States (Stumella
ludoviciana) the males engage in fierce conflicts, " but at
the sight of a female they all fly after her as if mad." "

Vocal and Instrumental Music. — With birds the voice
serves to express various emotions, such as distress, fear,
anger, triumph, or mere happiness. It is apparently
sometimes used to excite terror, as with the hissing noise
made by some nestling birds. Audubon " relates that a
night-heron (Ardea nycticorax, Linn.), which he kept
tame, used to hide itself when a cat approached, and then
" suddenly start up uttering one of the most frightful cries,
apparently enjoying the cat's alarm and flight." The

» 'Land and Water,' July 25, 1868, p. 14.

84 Audubon's 1 Ornitholog. Biography ; ' on Tetrao cupido, vol. ii. p.
492; on the Sturnus, vol. it p. 219.

>s 4 Ornithological Biography,' vol. v. p. 601.

Chap. XIII.]

VOCAL MUSIC.

40

common domestic cock clucks to the hen, and the hen to
her chickens, when a dainty morsel is found. The hen,
when she has laid an egg, " repeats the same note very
often, and concludes with the sixth above, which she
holds for a longer time;"26 and thus she expresses her
joy. Some social birds apparently call to each other for
aid; and as they flit from tree to tree, the flock is kept
together by chirp answering chirp. During the noctur-
nal migrations of geese and other water-fowl, sonorous
clangs from the van may be heard in the darkness over-
head, answered by clangs in the rear. Certain cries
serve as danger-signals, which, as the sportsman knows to
his cost, are well understood by the same species and by
others. The domestic cock crows, and the humming-bird
chirps, in triumph over a defeated rival. The true song,
however,, of most birds and various strange cries are
chiefly uttered during the breeding-season, and serve as a
charm, or merely as a call-note, to the other sex.

Naturalists are much divided with respect to the object
of the singing of birds. Few more careful observers ever
lived than Montagu, and he maintained that the "males
of song-birds and of many others do not in general search
for the female, but, on the contrary, their business in the
spring is to perch on some conspicuous spot, breathing
out their full and amorous notes, which, by instinct, the
female knows, and repairs to the spot to choose her male.'" 27
Mr. Jenner Weir informs me that lliis is certainly the case
with the nightingale. l>cchstcin, who kepi birds during
his whole life, asserts that " the female canary always
chooses the best singer, audlhat in a stale of nature the

female finch selects thai male oul of a hundred whose
notes please her most.1''8 There can he no doubl that

2fl Th(! Hon. Dainea Barrlngton, 'Philosoph, transact.' 1778, p, S5S,

21 'Ornithological Dictionary,' 1888, p, 175.

"*Nfttnrgeschichte dor StubenvOgel,' ism, i, 4. Mr, Harri on Well

50

SEXUAL SELECTION: BIRDS.

[Part II.

birds closely attend to each other's song. Mr. Weir has
told me of the case of a bullfinch which had been taught
to pipe a German waltz, and who was so good a performer
that he cost ten guineas ; when this bird was lirst intro-
duced into a room where other birds were kept and he
began to sing, all the others, consisting of about twenty
linnets and canaries, ranged themselves on the nearest
side of their cam s, and listened with the greatest interest
to the new performer. Many naturalists believe that the
singing of birds is almost exclusively " the effect of rival-
ry and emulation " and not for the sake of charming their
mates. This was the opinion of Daines Harrington and
White of Selborne, who both especially attended to this
subject.39 Barrington, however, admits that " superiority
in song gives to birds an amazing ascendency over others,
as is well known to bird-catchers."

It is certain that there is an intense degree of rivalry
between the males in their singing. Hird-fanciers match
their birds to see which will sing longest ; and I was told
by Mr. Yarrell that a first-rate bird will sometimes sing
till he drops down almost dead, or, according to Bech-
stein," quite dead from rupturing a vessel in the lungs.
Whatever the cause may be, male birds, as I hear from
Mr. Weir, often die suddenly during the season of song.
That the habit of singing is sometimes quite independent
of love is clear, for a sterile hybrid canary-bird has been
described" as singing while 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.

•

likewise writes to me: "I am informed that the best singing males gen
erally get a mate first when they are bred in the same room."

" 'Philosophical Transactions/ 1778, p. 263. White's * Natural His-
tory of Selborne,' vol i. 1825, p. 246.

» 4 Naturges. der Stubenvdgel,' 1840, s. 252.

81 Mr. Bold, 4 Zoologist,' 1843-'44, p. 659.

Chap. XIII.]

VOCAL MUSIC,

51

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, while a stuffed bird, sur-
rounded by limed twigs, is exposed to view. In this man-
ner a man, as Mr. Weir informs me, has caught, in the
course of a single day, 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 ordi-
nary male chaffinch is only sixpence, Mr. Weir saw one
bird for which the bird-catcher asked three pounds ; the
test of a really good singer being that it will continue to
sing while the cage is swung round the owner's head.

That birds should sing from emulation as well as for
the sake of charming the female, is not at all incompatible ;
and, indeed, might have been expected to go together,
like decoration and pugnacity. Some authors, however,
argue that the song of the male cannot serve to charm the
female, because the females of some few species, such as
the canary, robin, lark, and bullfinch, especially, as Bech-
stcin remarks, when in a state of widowhood, 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,33 for this disturbs all the
usual functions connected with the reproduction of the
species. Many instances have already been given of the
partial transference of secondary masculine characters to
the female, so that it is not at all surprising that the fe-
males of some species should possess the power of song.
It has also been argued, that the song of the male cannot
serve as a charm, because (he males of certain specie*, for
instance, of the robin, sing during the autumn/" Hut

:iM). Bftrrfagton, 'Phil. Transact.' 177:!, ]>. 2<V2. HoeliKtcin, 4 Stu-
bonv5geV 1840, §. 4.

" Tbll is likewise tlu? nine with tlx? wiiter-ouzel, sm- Mr. Ilcphiirii in
the PZodtogiit,' 1846 1846, p, 1008:

52

SEXUAL SELECTION': BIRDS.

[Part II.

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 rly
easily, gliding and sailing through the air obviously for
pleasure ! The cat plays with the captured mouse, and
the cormorant with the captured fish. The weaver-bud
(Ploceus), when confined in a cage, amuses itself by neat-
ly weaving blades of grass between the wires of its cage,
Birds which habitually fight during the breeding-season
are generally ready to fight at all times; and the males of
the capercailzie sometimes hold their balzens or leks at the
usual place of assemblage during the autumn.34 Hence it
is not at all surprising that male birds should continue
singing for their own amusement after the season for
courtship is over.

Singing is to a certain extent, as shown in a previous
chapter, an art, and is much improved by practice. Birds
can be taught various tunes, and even the anmelodionfe
sparrow has learned to sing like a linnet. They acquire
the song of their foster-parents 86 and sometimes that of
their neighbors." All the common songsters belong to
the Order of Insessores, and their vocal organs are much
more complex than those of most other birds ; yet it is a
singular fact that some of the Insessores, such as ravens,
crows, and magpies, possess the proper apparatus," 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

84 L. Lloyd, ' Game-Birds of Sweden,' 1867, p. 25.

85 Barrington, ibid. p. 264. Bechstein, ibid. 8. 5.

M Dureau de la Malle gives a curious instance (' Annales des Sc. Nat.'
3d series, Zoolog. torn. x. p. 118) of some wild -blackbirds in his garden
in Paris which naturally learned from a caged bird a republican air.

17 Bishop, in 'Todd's Cyclop, of Anat. and Phys.' voL iv. p. 1496.

M As stated by Barrington in ' Philosoph. Transact.' 1773, p. 262

Chap. XIII.]

VOCAL MUSIC.

53

males than in the females ; but with this slight exception
there is no difference in the vocal organs of the two sexes,
although the males of most species sing so much better
and more continuously than the females.

It is remarkable that only small birds properly sing.
The Australian genus Menura, however, must be ex-
cepted; for the Menura Alberti, which is about the size of
a half-grown turkey, not only mocks other birds, but " its
own whistle is exceedingly beautiful and varied." The
males congregate and form " corroborying places," where
they sing, raising and spreading their tails like peacocks
and drooping their wings.30 It is also remarkable that
the birds which sing are rarely decorated with brilliant
colors or other ornaments. Of our British birds, except-
ing the bullfinch and goldfinch, the best songsters are
plain-colored. The king-fisher, bee-eater, roller, hoopee,
woodpeckers, etc., utter harsh cries; and the brilliant
birds of the tropics are hardly ever songsters.40 Hence
blight colors 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 colors were dangerous to the
species, other means would have to be employed to charm
the females; and the voice being rendered melodious
would offer one such means.

In some birds the vocal organs differ greatly in the
two sexes. In the Tetrao cupido (Fig. 39) the male has
two bare, orange-colored sacs, one on each side of the
neck; and these are largely inflated when the male, dur-
ing the breeding-season, makes a curious hollow sound,
audible at a great distance. Auduhon proved thai the
sound was intimately connected with this apparatus,

89 Gould, ' Hand-book to the Birds of Australia,' vol. i. inc.;,, pp. :;«»s .
810. See also Mr. T. W. Wood in the 'Student,1 April, 1870, p. LS&
40 See remarks to this elVeet in Gould'l * Introduction to the Trot hi-

lida,4 1861, p. 22.

54

SEXUAL SELECTION: BIRDS.

[Taut CL

which reminds us of the air-sacs on each side of the
mouth of certain male frogs, for he found that the sound
was much diminished when one of the sacs of a tame
bird was pricked, and when both were pricked it was

Chap. XIII.]

VOCAL- MUSIC.

altogether stopped. The female has " a somewhat similar,
though smaller, naked space of skin on the neck; but this
is not capable of inflation." 41 The male of another kind of
grouse (Tetrao urophasianus) , while courting the female,
has his " bare yellow oesophagus inflated to a prodigious
size, fully half as large as the body;" and he then utters
various grating, deep hollow tones. With his neck-feath-
ers erect, his wings lowered and buzzing on the ground,
and his long pointed tail spread out like a fan, he displays
a variety of grotesque attitudes. The oesophagus of the
female is not in any way remarkable.42

It seems now well made out that the great throat-
pouch of the European male bustard [Otis tarda), and of
at least four other species, does not serve, as was formerly
supposed, to hold water, but is connected with the utter-
ance, during the breeding-season, of a peculiar sound re-
sembling "ock." The bird while uttering this sound
throws himself into the most extraordinary attitudes. It
is a singular fact that, with the males of the same species,
the sac is not developed in all the individuals.43 A
crow-like bird inhabiting South America (Cephalopterus
ornatus, Fig. 40) is called the umbrella-bird, from its im-
mense top-knot, formed of bare white quills surmounted

41 ' The Sportsman and Naturalist in Canada,' by Major W. Ross
King, 1866, pp. 144-146. Mr. T. W. Wood gives in the 'Student'
(April, 1870, p. 116) an excellent account of the attitude and habits of
this bird during its courtship. He states that the ear-tufts or neck-
plumes arc erected, so that they meet over the crown of the head.

42 Richardson, 'Fauna Bor. Americana: Birds,' 1831, p. 359. Audu-
bon, ibid. vol. iv. p. 507.

43 The following papers have been lately written on this subject:

Prof. A. Newton, is the 'Ibis,1 L862, p. l<>? ; Dr. Oullen, ibid. 1865, p.
145; Mr. Flower, in ' I 'roe. Zool. Soe.' IH65, p. 717; and l>r. Murie, in
4 Proc Zool. Soc' ik(»h, j). i7i. In this latter paper an exoelleni Bgnre

is given of the male Australian Mustard in lull display with the sue dis-
tended.

50

SEXUAL SELECTION: BIRDS.

| I'art II.

by dark-blue plumes, which it can elevate into a great
dome no less than- five inches in diameter, covering the
whole head. This bird has on its neck a long, thin, cylin-
drical, fleshy appendage, which is thickly clothed with

MI

: V

Pio. 40.— The Umbrella-Bird, or Cophaloptenm ornatus (male, from Ilrehm).

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 de-
velopment of the trachea and vocal organs." It is di-
lated when the bird utters its singularly deep, loud, and

Chap. XIII.]

VOCAL MUSIC.

57

long-sustained fluty note. The head-crest and neck-ap-
pendage are rudimentary in the female.44

The vocal organs of various web-footed and wading
birds are extraordinarily complex, and differ to a certain
extent in the two sexes. In some cases the trachea is
convoluted, like a French horn, and is deeply embedded
in the sternum. In the wild-swan ( Cygnus ferus) it is
more deeply embedded in the adult male than in the
female or young male. In the male Merganser the en-
larged portion of the trachea is furnished with an addi-
tional pair of muscles.45 But the meaning of these differ-
ences between the sexes of many Anatidae is not at all
understood; for the male is not always the more vo-
ciferous ; thus with the common duck, the male hisses,
while the female utters a loud quack.48 In both sexes of
one of the cranes (Grus virgo) the trachea penetrate- 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.47 So that highly-important structures have 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

44 Bates, 'The Naturalist on the Amazons,' 1803, vol. ii. p. 28 1 ; WaV
lace, in 4 Proc. Zool. Hoc' 1850, p. 200. A new species, with a still
larger neck-appendage (C. pcnduliycr), has lately been discovered, see
4 Ibis,' vol. i. p. 457.

*J Hishop, in Todd's 'Cyclop, of Anat. and I'hys.' vol. iv. p. U'.Mi.

40 The spoonbill (Platalea) baa its trachea convoluted Into • figure of

eight, and yet this bird (Jerdon, 4 Itirds of India, 1 \ oi iii. p. 768) il

mute; but Mr. Blyth Infonni me thai the convolution! ere no1 ooneteat

ly present, so that perhaps they are now tending toward abortion,

41 • Elements of Cotnp. Anat.' by It. Wagner, Eng. tranalal 1840, p.
1 11. With respect lo the swan, as given above, ^ arrell'H ' Bltt of Utit-
ish Minis,' lid edit. IN-Ifi, vol. iii. p. \\)\\.

58

SEXUAL SELECTION: BIRDS.

[Part II.

the female. The soft cooing of the turtle-dove ami of
many pigeons, it may be presumed, pleases the female.
When the female of the wild-turkey utters her call in
the morning, the male answers by a different note from
the gobbling noise which he makes, when with erected
feathers, rustling wings, and distended wattles, he pull's
and struts before her.'" The s]>< I of the blackcock cer-
tainly 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 blackcock continues his
sj>el 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 already present are
thus charmed.4" The voice of the common rook is known
to alter during the breeding-season, and is therefore in
some way sexual.60 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 color, judging by the inharmonious
contrast of their bright-yellow and blue plumage ? It is
indeed possible that the loud voices of many male birds
may be the result, without any advantage being thus
gained, of the inherited effects of the continued use of
their vocal organs, when they are 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, and the

48 C. L. Bonaparte, quoted in the 4 Naturalist Library : Birds,' voL
xiv. p. 126.

*» L. Lloyd, 'The Game-Birds of Sweden,' etc., 1867, pp. 22, 81.
50 Jenner, 'Philosoph. Transactions,' 1824, p. 20.

Chap. XIII.] INSTRUMENTAL MUSTC.

50

vibratory movement apparently serves merely to make a
noise, for it can hardly add to the beauty of their plu-
mage. Turkey-cocks scrape their wings against the
ground, and some kinds of grouse thus produce a buzzing
sound. Another North American grouse, the Tetrao um-
bellus, when with his tail erect, his ruffs displayed, " he
shows off his finery to the females, who lie hid in the
neighborhood," drums rapidly with his " lowered wings
on the trunk of a fallen tree," or, according to Audubon,
against his own body ; the sound thus produced is com-
pared 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." In
the Himalayas the male of the Kalij-pheasant " often makes
a singular drumming noise with his wings, not unlike the
sound produced by shaking a stiff piece of cloth." On the
west coast of Africa the little black-weavers (Ploceus ?)
congregate in a small party on the bushes round a small
open space, and sing and glide through the air with
quivering wings, " which make a rapid whirring sound
like a child's rattle." One bird alter another thus per-
forms for hours together, but only during the court ing-
season. At this same season the males of certain night-
jars (Caprimulgus) make a most strange noise with their
wings. The various species of woodpeckers strike a
sonorous branch with their beaks, with so rapid a vibrato-
ry movement that "the head appears to he in two places
at once." The sound thus produced is audible at a con-
siderable distance, but cannot he described; and 1 led
sure that ils cause would never be con jeet ured by any one
who heard it, lor the first lime. As this jarring sound is
made chiefly during the breeding-season, il has l.ren con-
sidered as a lovc-song ; but il is perhaps more Btriotl] I

love-call. The female, when drives from her n<^t, has

been observed thus to call her mate, \\h<> answered in the

60

SEXUAL SELECTION: BIRDS.

I Taut II.

same manner and soon appeared. Lastly, the male 1 1< »<>)><>('
(()>"/»/</>"/'■<) comliims vocal and in>trimiental music ;
for during the breeding-season this bird, as Mr. Swinhoe
saw, flrst 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." When the male utters its
cry without striking his beak, the sound is quite different."

In the foregoing cases sounds are made by the aid of
structures already present and otherwise necessary ; but
in the following cases certain leathers have been specially
modified for the express purpose of producing the sounds.
The drumming, or bleating, or neighing, or thundering
noise, as expressed by different observers, which is made
by the common snipe (Scolopax gcdlinago) must have sur-
prised every one who has ever heard it. This bird, during

Fio. 41.-Outcr tail-feather of Scolopax palllnago (from Proc. Zool. 8oc. 1858).

the pairing-season, flies to " perhaps a thousand feet in
height," and, after zigzagging about for a time, descends
in a curved line, with outspread tail and quivering pinions,

11 For the foregoing several facts see, on Birds of Paradise, Brehm,
4 Thierleben,' Band iii. s. 325. On Grouse, Richardson, 'Fnuna Bor.
Americ. : Birds,' pp. 343, 359 ; Major W. Boss King, 4 The Sports-
man in Canada,' 1866, p. 156; Audubon, * American Ornitholog. Biog-
raph.' vol. i. p. 216. On the Kalij-pheasant, Jerdon, 'Birds of India,*
voL iii. p. 538. On the Weavers, * Livingstone's Expedition to the Zam-
besi,' 1865, p. 425. On Woodpeckers, Macgillivray, ' Hist, of British
Birds,' voL iii. 1840, pp. 84, 88, 89, 95. On the Hoopoe, Mr. Swin-
hoe, in 1 Proc. Zoolog. Soc.' June 23, 1863. On the Nicht-Jar, Audubon,
ibid vol. ii. p. 256. The English Night-Jar likewise makes in the spring
a curious noise during its rapid flight.

Chap. XIII.]

INSTRUMENTAL MUSIC.

61

with surprising velocity to the earth. The sound is emit-
ted only during this rapid descent. No one was able to
explain the cause, until M. Meves observed that on each
side of the tail the outer feathers are peculiarly formed
(Fig. 41), having a stiff, sabre-shaped shaft, with the ob-
lique barbs of unusual length, the outer webs being strong-
ly bound together. He found that, by blowing on these
feathers, or by fastening them to a long thin stick and
waving them rapidly through the air, he could exactly re-
produce 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
JS. frenata (Fig. 42),
four feathers, and in
>V. javensis (Fig. 43), Fl°- 48-°nter tail-feather of Scolopax JareMb.

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 WUsonit of the United States makes a switching
noise while descending rapidly to the earth.*1

In the male of the Chamcepetes unicolor (a large lt-i 1 1 i-
naeeous bird of America) the first primary wring-feather

is arched toward the tip and is much more attenuated than
in the female. In an allied bird, t lie P</i<!ojn ni</r<t, Mr.

Salvin observed a male, which, while it Hew downward
"with outstretched wines, gave forth a kind «•!' crashing,

Fig. 42.— Outer tail-feather of Scolopax frenata.

M See M. Me\ <■ ' • iiitnc-liiiK paper in ' Pine. '/..... I Sue.' I V. s. p 1
Kortlielial.il- of the nipr, Maepllivrav, 'lli-t. ItritMi Itinl .' \m| w p
871. For the Ainerieiin nnipe, Captain ItlaK i>t • »n, ' II. i»,' \«>l. \ 1st".::.

p. LSI

62

SEXUAL SELECTION: B1KDS.

| I'akt II.

rushing noise," like the falling of a tree." The male alone
of one of t lie Indian buMards (Xt/p/n <>t;<(, s uurih/.s) has i)s
primary wing-feathers greatly acuminated; and the male
of an allied species is known to make a humming noise
while courting the female." In a widely-different group
of birds, namely the Humming-birds, the males alone of

certain kinds have either the
shafts of their primary wing-
feat hers broadly dilated, or the
webs abruptly excised toward
the extremity. The male, for
instance, of S< hisj>ft<>rnx j>l<ity-
cercus, when adult, has the
first primary wing-feather (Fig.
44) excised in this manner.
While flying from flower to
flower he makes " a shrill, almost whistling noise ; " " but
it did not appear to Mr. Salvin that the noise was inten-
tionally made.

Lastly, in several species of a sub-genus of Pipra or
Manakin, the males have their secondary wing-feathers
modified, as described by Mr. Sclater, in a still more re-
markahlc manner. In the brilliantly-colored 1\ </<tir/o,sa
the first three secondaries are thick-stemmed and curved
toward the body; in the fourth and fifth (Fig. 45, a) the
change is greater ; and in the sixth and seventh (&, 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

u Mr. Salvin, in 'Proc. Zool. Soc' 1867, p. 160. I am much indebted
to this distinguished ornithologist for sketches of the feathers of the
Chamaepctes, and for other information.

M Jerdon, 'Birds of India,' vol. iii. pp. 618, 621.

u Gould, 1 Introduction to the Trocbilidse,' 1861, p. 49. Salvin,
4 Proc. Zoolog. Soc.' 1867, p. 160.

9*

Pio. 44.— Primary wing-feather of
a Humming-bird, the Selaspho-
rus p/uti/r, /■(•>/.< (from a nkctrh
by Mr. Salvin). Upper figure,
that of male ; lower figure, cor-
responding feather of female.

Chap. XIII.]

IX STR UME X TAL M USIC.

63

(c?, e,/) in the female. Even the bones of the wing which
support these singular feathers in the male are said by-
Mr. Fraser to be much thickened. These little birds
make an extraordinary noise, the first " sharp note being
not unlike the crack of a whip." 00

M Nclatrr, in ' I *!•«•€•. ZomI Smc.' I mill, p. '.tii( ainl in ' llii*,' \»>l. iv.
lHft'2, p. I7.V Also Siilvin, in • li. i : I M'.i i. |.

64

SEXUAL SELECTION: BIRDS.

[Part II.

The diversity of the sounds, both vocal and instrumen-
tal, made by the males of many species during the brecd-
ing-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 same conclusion with respect to insects.
It is not difficult to imagine the steps by which the notes
of a bird, primarily used as a mere call or for some other
purpose, might have been improved into a melodious. love-
song. This is somewhat more difficult in the case of the
modified feathers, by which the drumming, whistling, or
roaring noises, are produced. But we have seen that some
birds during their courtship flutter, shake, or rattle their
unmodified feathers together; and, if the females were led
to select the best performers, the males which possessed
the strongest or thickest, or most attenuated leathers,
situated on any part of the body, would be the most suc-
cessful ; and thus by slow degrees the feathers might be
modified to almost any extent. The females, of course,
would not notice each slight successive alteration in shape,
but only the sounds thus produced. It is a curious hot
that, in the same class of animals, sounds so different as
the drumming of the snipe's tail, the tapping of the wood-
pecker's beak, the harsh trumpet-like cry of certain water-
fowl, the cooing of the turtle-dove, and the song of the
nightingale, should all be pleasing to the females of the
several 6pecies. But we must not judge the tastes of dis-
tinct species by a uniform standard ; nor must we judge
by the st and:in I 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

« 'The Nile Tributaries of Abyssinia,' 1867, p. 208.

i

Chap. XIII.]

LOVE-ANTICS.

65

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 various birds, especially of the Gallinaceae, have already
been incidentally noticed; so that little need here be
added. In Northern America, large numbers of a grouse,
the Tetrao phasianellus, meet every morning during the
breeding-season on a selected level spot, and here they
run round and round in a circle of about fifteen or twenty
feet in diameter, so that the ground is worn quite bare,
like a fairy-ring. In these Partridge-dances, as they arc
called by the hunters, the birds assume the strangest atti-
tudes, and run round, some to the left and some to the
right. Audubon describes the males of a heron (Ardea
herodias) as walking about on their long legs with great
dignity before the females, bidding defiance to their rivals.
With one of the disgusting carrion-vultures (Cathartes
jota) the same naturalist states that "the gesticulations
and parade of the males at the beginning of the love-sea-
son 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 <-i>nr<<i) often
rises a few feet or yards in the air above sonic bush, and
" flutters with a fitful and fantastic motion, singing all the
while, and then drops to its perch." The great Knglish
bustard throws himself into indescribably odd attitudes
while courting the female, as has been figured by Wolf.
An allied Indian bustard [Otis Bengalemis) at Buch times
"rises perpendicularly into the air with a hurried flapping
of his wings, raising his crest and puffing onl the feathers
of his neck and breast, and then drops t.» the ground;"
he repeats this mamuuvrc several limes successively, at

the same time humming in a peculiar tour. Such females

06

SEXUAL SELECTION: BIRDS.

[Part Q.

as happen to be near " obey this saltatory summons," and
when they approach he trails his wings and spreads his
tail like a turkey-cock."

But the most curious case is afforded by three allied
genera of Australian birds, the famous Bower-birds — no
doubt the co-descendants of some ancient species which
first acquired the strange instinct of constructing bowers
for performing their love-antics. The bowers (Fig. 4G),
which, as we shall hereafter see, are highly decorated
with feathers, shells, bones, and leaves, are built on the
ground for the sole purpose of courtship, for their nests
are formed in trees. Both sexes assist in the erection <>!'
the bowers, but the male is the principal workman. So
strong is this instinct that it is practised under confine-
ment, and Mr. Strange has described 69 the habits of some
Satin Bower-birds, which he kept in his 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 eyes appear ready t<» start from his head;
he continues opening first one wing, and then the other,
uttering a low, whistling note, and, like the domestic
cock, seems to be picking up something from the ground,
until at last the female goes gently toward him." Cap-
tain Stokes lias described the habits and " play-houses "
of another species, the Great Bower-bird, which was seen

68 For Tetrao phasianellus, see Richardson, 4 Fauna Bor. America,' p.
361, and for further particulars Captain Blakiston, 4 Ibis,' 1863, p. 128.
For the Cathartes and Ardea, Audubon, ' Ornith. Biography,' vol. ii. p.
61, and vol. iii. p. 89. On the White-throat, Macgillivray, 4 Hist. British
Birds/ vol. ii. p. 364. On the Indian Bustard, Jerdon, 4 Birds of India,'
vol iii. p. 618.

M Gould, 4 Bland-book to the Birds of Australia,' voL L pp. 444, 449,
466. The bower of the Satin Bower-bird may always be seen in the
Zoological Society's Gardens, Regent's Park.

Chap. XIII.]

LOVE-ANTICS.

67

" amusing itself by flying backward and forward, taking
a shell alternately from each side, and carrying it through
the archway in its mouth." These curious structures,

68 SEXUAL SELECTION: BIRDS. (Paiit

formed solely as halls of assemblages, where both sexes
amuse themselves and pay their court, must cost t lie birds
much labor. 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 orna-
mented, and finally the rare cases in which the female is
somewhat more brightly colored than the male. As with
the artificial ornaments used by savage and civilized men,
so with the natural ornaments of birds, the head is the
chief seat of decoration."" The ornaments, as mentioned
at the commencement of this chapter, are wonderfully di-
versified. 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 colors are
fully displayed. Elegant ear-tufts (see Fig. 39 ante) are
occasionally present. The head is sometimes covered
with velvety down like that of the pheasant ; <>r is naked
and vividly colored; or supports fleshy appendages, fila-
ments, and solid protuberances. The throat, also, is
sometimes ornamented with a beard, or with wattles or
caruncles. Such appendages are generally brightly col-
ored, and no doubt serve as ornaments, though not always
ornamental in our eyes; for while the male is in the act
of courting the female, they often swell and assume more
vivid tints, as in the case of the male turkey. At such
times the fleshy appendages about the head of the male
Tragopan pheasant (Ceriornis temminckii) swell into a

90 See remarks to this effect, on the "Feeling of Beauty among Ani-
mals," by Mr. J. Shaw, in the 4 Athemeum,' Not. 24, 1866, p. 681.

Chap. XIII.] DECORATION. 69

large lappet on the throat and into two horns, one on
each side of the splendid top-knot ; and these are then
colored of the most intense bine which I have ever be-,
held. The African hornbill (Bucorax Abyssinicus) inflates
the scarlet bladder-like wattle on its neck, and with its
wing drooping and tail expanded " makes quite a grand
appearance." 61 Even the iris of the eye is sometimes
more brightly colored 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 colored more con-
spicuously in the male than in the female ; and " the ob-
lique grooves upon the sides of the lower mandible are
peculiar to the male sex." 02

The males are often ornamented with elongated feath-
ers or plumes, springing from almost every part of the
body. The feathers on the throat and breast are some-
times 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 of the
Argus pheasant. The body of this latter bird 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.88 The wing-feathers are not elongated
nearly so often as the tail-feathers; for their elongation
would impede the act of flight. Vet the beautifully ocel-
lated secondary wing-feathers of the male ArgUS pheasant
are nearly three feet in length; and, in a small African
night-jar (Cos/nrtoruis r> .rilhtri '//*), one of the primary
wing-feffthers, during the breeding-season, attains :i length
of twenty-six inches, while the bird itself is only ton inohea
in length. In another closely allied genus of night-jars,

Mr. Montoiro, ' [bin,' vol. iv. 1N«2, p. 889.
•* ' Land ami Water,' I NAN, p. *J 1 7.

■ Jardlne'i 'Naturalist Ubrsrj i Birds,1 \<>l ^ i ^ p L6&

70 SEXUAL SELECTION; BIRDS. [Part II.

•

the shafts of the elongated wing-feathers are naked, ex-
cept at the extremity, where there is a disk."4 Again, in
another genus of night-jars, the tail-feathers are even
still more prodigiously developed; so that we see the
same kind of ornament gained by the males of closely-
allied birds, through the development of widely-different
feathers.

It is a curious fact that the feathers of birds belonging
to distinct groups have been modified in almost exactly
the same peculiar manner. Thus the wing-feathers in one
of the above-mentioned night-jars are bare along the shaft
and terminate in a disk; or are, as they are sometimes
called, spoon or racket-shaped. Feathers of this kind
occur in the tail of a mot mot (Euirwmota superciliaris),
of a king-fisher, finch, humming-bird, parrot, several
Indian drongos (Dicrurw and K<loliu%, in one of which
the disk stands vertically), and in the tail of certain JJirds
of Paradise. In these latter birds, similar feather-, beau-
tifully 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
disks." The barbs of the feathers in various widely-dis-
tinct birds are filamentous or plumose, as with some
Herons, Ibises, Birds of Paradise, and Gallinaceje. In
other cases the barbs disappear, leaving the shafts bare;
and these in the tail of the Paradisea apoda attain s
length of thirty-four inches.0" Smaller feathers when thus
denuded appear like bristles, as on the breast of the
turkey-cock. As any fleeting fashion in dress comes to

•* Sclater, in the 'Ibis,' voL vi. 1864, p. 114. Livingstone, 'Expedi-
tion to the Zambesi,1 1865, p. 66.

84 Jcrdon, ' Birds of India,' vol. iii. p. 620.

•* Wallace, in 'Annals and Mag. of Nat. Hist.' vol. xx. 1867, p. 416;
and in his ' Malay Archipelago,' vol. ii. 1869, p. 890.

Chap. XIII.]

DECORATION.

71

be admired by man, so with birds a change of almost any-
kind in the structure or coloring 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 pri-
marily on all the feathers having nearly the same struct-
ure and manner of development, and consequently tend-
ing to vary in the same manner. We often see a ten-
dency 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 resembled,
to a certain extent, the racket-shaped feathers above de-
scribed. In certain breeds of the pigeon and fowl the
feathers are plumose, with some tendency in the shafts to
be naked. In the Sevastopol goose the scapular feathers
are greatly elongated, curled, or even spirally twisted,
with the margins plumose.87

In regard to color hardly any thing need here be said ;
for every one knows how splendid are the tints of birds,
and how harmoniously they are combined. The colors
are often metallic and iridescent. Circular spots are
sometimes surrounded by one or more different 1 y-shaded
zones, and are thus converted into ocelli. Nor need much
bo said on the wonderful differences between (he sexes, or
of the extreme beauty of the males of many birds. The
common peacock offers a striking instance. Female Birds
of Paradise are obscurely colored and destitute of all orna-
ments, while the males are probably the most highly
decorated of all birds, and in so many ways, that they
must bo seen to be appreciated. The elongated and
golden-orange plumes which spring from beneath the

81 Bm my work on 'The Variation of anlmali and Planti andai Do*
meBtioation,' vol. i. pp. 'J so, 2<>:i.

SFXTAL SKf.KCTloX: HINDS.

Chap. XIII.] DECORATION. 73

in the centre of which the head " looks like a little eme-
rald sun with its rays formed by the two plumes." 68 In
another most beautiful species the head is bald, " and of a

Flu. IH. F.ciplinrnlM nrnntuM, male and f. innlr il'r.nii Hivliiii'

* Quoted from M. do liiifri'rtimyo, in 'Annul* uml M.i • «>| N.ii lli-i '
18

74

SEXUAL SELECTION : BIRDS.

[Part EL

vol. xiii. 1854, p. 157; see also Mr. Wallace's much fuller account in voL
xx- 1857, p. 412, and in his Malay Archipelago.

Chap. XIII.]

DECORATION.

75

rich cobalt blue, crossed by several lines of black velvety
feathers." 69 '

Male humming-birds (Figs. 48 and 49) almost vie with
Birds of Paradise in their beauty, as every one will admit
who has seen Mr. Gould's splendid volumes or his rich
collection. It is very remarkable in how many different
ways these birds are ornamented. Almost every part of
the plumage has been taken advantage of and modified ;
and the modifications have been carried, as Mr. Gould
showed me, to a wonderful extreme in some species be-
longing to nearly every sub-group. Such cases are curi-
ously 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
belonging to the same species in other characters ; and
these have been seized on by man and augmented to an
extreme point — as the tail of the fantail-pigeon, the hood
of the jacobin, the beak and wattle of the carrier, etc.
The sole difference between these cases is that in the
one the result is due to man's selection, while in the
other, as with Humming-birds, Birds of Paradise, etc., it
is due to sexual selection — that is, to the selection by the
females of the more beautiful males.

I will mention only one other bird, remarkable from
the extreme contrast in color between the sexes, namely,
the famous Bell-bird (ChasmorJiynchus niveus) of South
America, the note of which can be distinguished at the
distance of nearly three miles, and astonishes every one
who first hears it. The male is pure white, while the fe-
male is dusky-green; and the former color with terres-
trial species of moderate size and inott'ensive habits i> very
rare. The male, also, as described by Waterton, h:is |
Bpiral tube, nearly three inches in length, which rises from
the base of the beak. It, is jet-black, dotted over with

■» Wallace, 4Thc Malay Archipelago,1 rot IL 1869, i>. 405.

76

SEXUAL SELECTION: BIRDS.

[Part II.

minute downy feathers. This tube can be inflated with
air, through a communication with the palate ; and when
not inflated hangs down on one side. The genus consists
of four species, the males of which are very distinct, while
the females, as described by Mr. Sclater in a most inter-
esting paper, closely resemble each other, thus offering an "
excellent instance of the common rule that within the
same group the males differ much more from each other
than do the females. In a second species ( C. nudicollis)
the male is likewise snow-white, with the exception of a
large space of naked skin on the throat and round the
eyes, which during the breeding-season is of a fine green
color. In a third species (C. tricarunculatus)* the head
and neck alone of the male are white, the rest of the body
being chestnut-brown, and the male of this species is pro-
vided 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.70

The colored plumage and certain other ornaments of
the males when adult are either retained for life or are
periodically renewed during the summer and breeding-sea-
son. At this season the beak and naked skin about the
head frequently change color, as with some herons, ibises,
gulls, one of the bell-birds just noticed, etc. In the white
ibis, the cheeks, the inflatable skin of the throat, and the
basal portion of the beak, then become crimson." In one
of the rails, Gallicrex cristatus, a large red caruncle is de-
veloped during this same period on the head of the male.
So it is with a thin horny crest on the beak of one of the
pelicans, P. erythrorhynchus ; for, after the breeding-sea-
son, these horny crests are shed, like horns from the heads

70 Mr. Sclater, 'Intellectual Observer,' Jan. 1867. 1 Waterton's Wan-
derings,' p. 118. See also Mr. Salvin's interesting paper, with a plate, in
the * Ibis,' 1865, p. 90.

« » Land and Water,' 1867, p. 394.

Chap. XIII.] DOUBLE ANNUAL MOULT.

77

of stags, and the shore of an island in a lake in Nevada
was found covered with these curious exuviae.72

Changes of color in the plumage according to the sea-
son depend firstly on a double annual moult, secondly on
an actual change of color in the feathers themselves, and
thirdly on their dull-colored margins being periodically
shed, or on these three processes more or less combined.
The shedding of the deciduary margins may be compared
with the shedding by very young birds of their down ;
for the down in most cases arises from the summits of the
first true feathers.78

With respect to the birds which annually undergo a
double moult, there are, firstly, some kinds, for instance
snipes, swallow-plovers (Glareolse) and curlews, in which
the two sexes resemble each other and do not change
color at any season. I do not know whether the winter
plumage is thicker and warmer than the summer plumage,
which seems, when there is no change of color, the most
probable cause of a double moult. Secondly, there are
birds, for instance, certain species of Totanus and other
grallatores, the sexes of which resemble each other, but
have a slightly different summer and winter plumage.
The difference, however, in color in these cases is so
slight 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 arc 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 color;
but the females, though moulting twice, retain the same
colors throughout the year, while the males undergo a

n Mr. D. 0. Elliot, in ' Proo. ZooL Soc.' 1869, p. 589.
n 1 Nitzsch's Pterylography,' edited l>y P. I,. Sc-latcr. May Soc.
18G7, p. M.

78

SEXUAL SELECTION: BIRDS.

[Part II.

change, sometimes, as with certain bustards, a great
change of color. Fifthly and lastly, there are birds the
sexes of which differ from each other in both their sum-
mer and winter plumage, but the male undergoes a
greater amount of change at each recurrent season than .
the female — of which the Ruff {Machetes pugnax) offers •
a good instance.

With respect to the cause or purpose of the differences
in color between the summer and winter plumage, this
may in some instances, as with the ptarmigan,7* serve
during both seasons as a protection. When the difference
between the two plumages is slight it may perhaps be at-
tributed, as already remarked, to the direct action of the
conditions of life. But with many birds there can hardly
be a doubt that the summer plumage is ornamental, even
when both sexes are alike. We may conclude that this is
the case with many herons, egrets, etc., for they acquire
their beautiful plumes only during the breeding-season.
Moreover, such plumes, top-knots, etc., though possessed
by both sexes, are occasionally a little more highly devel-
oped 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, frequent-
ly checks the development of their secondary sexual char-
acters, but has no immediate influence on any other char-
acters ; and I am informed by Mr. Bartlett that eight or
nine specimens of the Knot (Tringa canutus) retained
their unadorned winter plumage in the Zoological Gar-

14 The brown mottled summer plumage of the ptarmigan is of as much
importance to it, as a protection, as the white winter plumage ; for, in
Scandinavia, during the spring, when the snow has disappeared, this bird
is known to suffer greatly from birds of prey, before it has acquired its
summer dress : see Wilhelm von Wright, in Lloyd, ' Game-Birds of
Sweden,' 1867, p. 126.

Chap. XIII.] DOUBLE ANNUAL MOULT.

79

dens 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 plu-
mage of many other birds.75

From the foregoing facts, more especially from neither
sex of certain birds changing color 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 colors
throughout the year, we may conclude that the habit of
moulting twice in the year has not been acquired in order
that the male should assume during the breeding-season
an ornamental character; but that the double moult, hav-
ing 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,
with closely-allied birds, some species should regularly
undergo a double annual moult, and others only a single
one. The ptarmigan, for instance, moults twice or even
thrice in the year, and the blackcock only once : some of
the splendidly-colored honey-suckers (Nectariniffl) of In-
dia and some sub-genera of obscurely-colored pipits (An-
thus) have a double, while others have only a single an-
nual moult.76 But the gradations in the manner of moult*
ing, which are known to occur with various birds, show
us how species, or whole groups of species, might have

75 In regard to the previous statements on moulting, see, on snipes,
etc., Macgillivray, 'Hist. Brit. Birds,' vol. iv. p. It7 1 ; on (llareolsB, cur-
lews, and bustards, Jerdon, 'Birds of India,1 vol. iii. pp. 615, 880, 088;
on Tetanus, ibid. p. 7<»0; on (lie plumes of borons, ibid. p. 7">S, and Mac-
gillivray, vol. iv. pp. 485, 444, and Mr. Stafford Allen, in the ' litis,' vol.
v. 180U, p. 8.8.

70 On t lie moulting of the ptarmigan, see (iould's 'Birds of (beat
Britain.' On Hie lionev-suekeis, .lenlon, ' Birds of India,1 fOl i. pp. :!.'■'.»,
3(15, 869. On Hie moulting of Antbus, see Blvtli, in 1 Ibis,' IS07, p.

80

SEXUAL SELECTION: BIRDS.

[Pabt H

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 com-
plete, some feathers being renewed, and some changed in
color. There is also reason to believe that with certain
bustards and rail-like birds, which properly undergo a
double moult, some of the older males retain their nup-
tial plumage throughout the year. A few highly-modiiied
feathers may alone be added during the spring to the
plumage, as occurs with the disk-formed tail- feat hers of
certain drongos (Bhringa) in India, and with the elon-
gated 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. A gradation can also be
shown to exist in the length of time during which fit Ik r
annual plumage is retained; so that the one might come
to be retained for the whole year, the other being com-
pletely lost. Thus the Machetes 2yuGnax retains his raff
in the spring for barely two months. The male widow-
bird (G/tera progne) acquires in Natal his fine plumage
and long tail-feathers in December or January, and loses
them in March ; so that they are retained during only
about three months. Most species which undergo a
double moult keep their ornamental feathers for about
six months. The male, however, of the wild Gallug
bankiva retains his neck-hackles for nine or ten months ;
and, when these are cast off, the underlying black feathers
on the neck are fully exposed to view. But, with the do-
mesticated descendant of this species, the neck-hackles of.
the male are immediately replaced by new ones; so that
we here see, with respect to part of the plumage, a double
moult changed under domestication into a single moult."

11 For the foregoing statements in regard to partial moults, and on
old males retaining their nuptial plumage, see Jerdon, on bustards and

Chap. XIII.J

DOUBLE ANNUAL MOULT.

81

The common drake (A?ias boschas) is well known after
the breeding-season 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 extraordinary circum-
stance, that seems to bid defiance to all human reasoning.
But he who believes in the gradual modification of spe-
cies will be far from feeling surprised at finding grada-
tions 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 ap-
parently is the case with the male of a not distantly-allied
bird, namely the Merganser serrator, for the males are
said to " undergo a change of plumage, which assimilates
them in some measure to the female." By a little further
acceleration in the process, the double moult would be
completely lost.78

Some male birds, as before stated, become more bright-
ly colored in the spring, not by a'vernal moult, but either
by an actual change of color in the feathers, or by their
obscurely-colored deoidUary margins being shed. Changes
of color thus caused may last for a longer or shorter time.
With the Pelccanus onocrotalus a beautiful rosy tint, with

plovers, in 'Birds of India,' vol. iii. pp. 017, 0:57, 709, 711. Also Bljth
in 'Land and Water,' 1807, p. 84. On the Vidua, 'Ibis,' vol. iii. 1861,
p. 133. On the Drongo Shrikes, Jordon, ibid. vol. i. p. 435. On tho
vernal moult of tho Herodia* bubulati, Mr. S. 8. Allen, In ' Ibis,1 1864, p.
33. On Oallm btuthivt, Blyth, in 'Annuls and Hag, of Nat. 1 1 i.-t .' \<>l.
i. 1848, p. 4fif> ; sec, also, on this subject, my 'Variation of Animals
under Domestication, ' vol. i. p. T.W>.

MSco IfacgUlirray, ' Ili-t. British Birds' (vol. v. pp. 34, 7<», *-»'2:t>,
on the moulting of tlm Aiiutid»i«, with quotations from Waterloo and
Montagu. Also Y anvil, 'Hist, of llritish birds,' vol. iii. p.

88

SEXUAL SELECTION: BIRDS.

[Part II.

lemon-colored marks on the breast, overspreads the whole
plumage in the spring; but these tints, as Mr. Selater
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 bright-colored, while other finches
undergo no such change. Thus the FringiUa tristis of the
United States (as well as many other American species)
exhibits its bright colors only when the winter is past,
while our goldfinch, which exactly represents this bird in
habits, and our siskin, which represents it still more close-
ly 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, while in
Madeira these colors are retained throughout the year.79

Display by Male Birds of their Plumage. — Ornaments
of all kinds, whether permanently or temporarily gained,
are sedulously displayed by the males, and apparently
serve to excite, or attract, or charm, the females. But the
males will sometimes display their ornaments, when not
in the presence of the females, as occasionally occurs with
grouse at their balz-places, and as may be noticed with
the peacock; this latter bird, however, evidently wishes
for a spectator of some kind, and will show off his finery,
as I have often seen, before poultry or even pigs.80 All
naturalists who have closely attended to the habits of

19 On the pelican, see Selater, in 4Proc. Zool. Soc' 1868, p. 265.
On the American finches, see Audubon, ' Ornith. Biography,' vol. i. pp.
174, 221, and Jerdon, 'Birds of India,' vol. ii. p. 883. On the FringiUa
cannabina of Madeira, Mr. E. Vernon Harcourt, 'Ibis,' vol. v. 1863,
p. 230.

80 See also ' Ornamental Poultry,' bv Rev. E. S. Dixon, 1848, p. 8.

Chap. XIII. j DISPLAY BY THE MALE.

S3

birds, whether in a state of nature or under confinement,
are unanimously of opinion that the males delight to dis-
play their beauty. Audubon frequently speaks of the
male as endeavoring 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 81 insists that the beautiful plumage
of the male serves "to fascinate and attract the female."
Mr. Bartlett, at the Zoological Gardens, expressed himself
to me in the strongest terms to the same effect.

It must be a grand sight in the forest of India " to
come suddenly on twenty or thirty pea-fowl, the males
displaying their gorgeous trains, and strutting about in
all the pomp of pride before the gratified females." The
wild-turkey-cock erects his glittering plumage, expands
his finely-zoned tail and barred wing-feathers, and alto-
gether, with his gorged crimson and blue wattles, makes
a superb, though, to our eyes, grotesque appearance.
Similar facts have already been given with respect to
grouse of various kinds* Turning to another Order. The
male Rupicola crocea (Fig. 50) is one of the most beaut iful
birds in the world, being of a splendid orange, with some
of the feathers curiously truncated and plumose. The fe-
male is brownish-green, shaded with red, and has a much
smaller crest. Sir R. Schomburgk has described their
courtship; he found one of their meeting-places where ten
males and two females were present. The space was
from four to five feet tn diameter, and appeared t<> have
been cleared of every blade of grass and smoothed as it*
by human hands. A male " was capering to the apparent
delight of several others. Now spreading its wings,

81 4 BIrdi of Iinliii,' [ntroduot vol. i. p, rxhr. ; on 1 1 1 « » pMOOok, foL
Hi. p. 507. See Gould's ' Introduction t<> the Troohilidw,' L801t pp^ Iff,
ill.

SI

SEXUAL SELECTION: BIRDS.

|Pakt II.

throwing up its head, or opening its tail like a fan ; now-
strutting about with a hopping gait until tired, when it
gabbled some kind of note, and was relieved by another.

Fig. rXX— Rap i cola crocca, male (from Brchtn).

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

Chap. XIII.]

DISPLAY BY THE MALE.

85

then are able to kill, with their poisoned arrows, four or
five males, one after the other.82 With Birds of Paradise
a dozen or more full-plumaged males congregate in a tree
to hold a dancing-party, as it is called by the natives ;
and here flying about, raising their wings, elevating their
exquisite plumes, and making them vibrate, 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 Archi-
pelago, are said to take much care in keeping their feathers
clean ; often spreading them out, examining them, and re-
moving every speck of dirt. One observer, who kept
several pairs alive, did not doubt that the display of the
male was intended to please the female.88

The gold -pheasant ( Thaumalea picta) during his
courtship not only expands and raises his splendid frill,
but turns it, as I have myself seen, obliquely toward the
female on whichever side she may be standing, obviously
in order that a large surface may be displayed before
her.8* Mr. Bartlett has observed a male Polyplectron
(Fig. 51) in the act of courtship, and has shown me a
specimen stuffed in the attitude then assumed. The tail
and wing feathers of this bird are ornamented with beau-
tiful 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 lias to show off, at the same time, his rich

" 'Journal of R. Geograph. Soc.' vol. x. lsio, p. 236.

83 4 Annals and Mag. of* Nat. Mist.' vol. ls.Vl, \>. 1 r» 7 ; also Wal-
lace, ibid. vol. xx. lsr.7, p. 412, and 'The Malay Archipelago,' roL ii.
18fW, p. 251 AIho Dr. Bennett, as quoted by Brehm, 1 Thierleben,' B,
HL h. 326.

M Mr. T. W. Wood has given ('Tin- Student,' April, ls7o, p. 11.'.) u
full account of thin manner of display, which li<' oalla the lateral "i <>nr

■ided, by the gold-phcaHanl and by tin- .lnpnnc.se pheasant, I'h. t , /wi. ,./<•>•

86

SEXUAL SELECTION: BIRDS.

[I'AilT II.

blue throat and breast. But the breast of the Polyplec-
tron is obscurely colored, and the ocelli are not confined
to the tail-feathers. Consequently the Polyplectron does

Chap. XIII.]

DISPLAY BY THE MALE.

ST

not stand in front of the female ; but he erects and ex-
pands his tail-feathers a little obliquely, lowering the ex-
panded wing on the same side, and raising that on the
opposite side. In this attitude the ocelli over the whole
body are exposed before the eyes of the admiring female
in one grand bespangled expanse. To whichever side she
may turn, the expanded wings and the obliquely-held tail
are turned toward her. The male Tragopan pheasant
acts in nearly the same manner, for he raises the feathers
of the body, though not the wing itself, on the side which
is opposite to the female, and which would otherwise be
concealed, so that nearly all the beautifully-spotted feath-
ers are exhibited at the same time.

The case of the Argus pheasant is still more striking.
The immensely-developed secondary wing-feathers, which
are confined to the male, are ornamented with a row of
from twenty to twenty-three ocelli, each above an inch in
diameter. The feathers are also elegantly marked witli
oblique dark stripes and rows of spots, like those on the
skin of a tiger and leopard combined. The ocelli are so
beautifully shaded that, as the Duke of Argyll remarks,86
they stand out like a ball lying loosely within a socket.
But when I looked at the specimen in the British Museum,
which is mounted with the wings expanded and trailing
downward, I was greatly disappointed, for the ocelli ap-
peared flat or even concave. Mr. Gould, however, soon
made the case clear to me, for he had made a drawing of
a male while he was displaying himself At such timet
the long secondary feathers in both wings arc vertically
erected and expanded ; and these, together with the enor-
mously-elongated tail-feathers, make a grand semicircular
upright fan. Now as soon as the wing-teat hers are held
in this position, and the light, shines on them from above,
the full effect of the shading comes out, .inn each ocellus
" ' The Kci^n of l.uw I si',7, p

ss

SEXUAL SELECTION: BIRDS.

[Part 0.

at once resembles the ornament called a ball and socket.
These feathers have been shown to several artists, and all
have expressed their admiration at the perfect shading.
It may well be asked, Could such artistically-shaded orna-
ments 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 primary wing-feathers, which in most gallinaceous
birds are uniformly colored, are in the Argus pheasant
not less wonderful objects than the secondary wing-feath-
ers. They are of a soft brown tint with numerous dark
spots, each of which consists of two or three black dots
with a surrounding dark zone. But the chief ornament is
a space parallel to the dark-blue shaft, which in outline
forms a perfect second feather lying within the true feath-
er. This inner part is colored of a lighter chestnut, and
is thickly dotted with minute white points. I have shown
this feather to several persons, and many have admired it
even more than the ball-and-socket feathers, and have de-
clared that it was more like a work of art than of Nature.
Now these feathers are quite hidden on all ordinary occa-
sions, but are fully displayed when the long secondary
feathers are erected, though in a widely-different manner;
for they are expanded in front like two little fans or
shields, one on each side of the breast near the ground.

Tin- ease of the male Argus pheasant is eminently in-
teresting, because it affords good evidence that the most
refined beauty may serve as a charm for the female, and
for no other purpose. We must conclude that this is the
case, as the primary wing-feathers are never displayed,
and the ball-and-socket ornaments are not exhibited in full
perfection, except when the male assumes the attitude of
courtship. T^e Argus pheasant does not possess brilliant
colors, so that his success in courtship appears to have

Chap. XIII.]

DISPLAY BY THE MALE.

80

depended on the great size of his plumes, and on the elab-
oration 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, though perhaps she
admires the. general effect rather than each separate de-
tail. He who thinks that he can safely gauge the discrimi-
nation and taste of the lower animals, may deny that the
female Argus pheasant can appreciate such refined beau-
ty ; but he will then be compelled to admit that the ex-
traordinary attitudes assumed by the male during the act
of courtshio, by which the wonderful beauty of his plu-
mage is fu .y displayed, are purposeless ; and this is a con-
clusion which I for one will never admit.

Although so many pheasants and allied gallinaceous
birds carefully display their beautiful plumage before the
females, it is remarkable, as Mr. Bartlett informs me, that
this is not the case with the dull-colored Eared and Cheer
pheasants ( Cross optllon auritum and Phcuianw Walli-
chii) • 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
lie lias not had such good opportunities for observing the
Cheer as the Eared pheasant. Mr. Jenner Weir, also,
finds that all male birds with rich or Strongly-character-
ized plumage are more quarrelsome than the dull-colonel
species belonging to the same groups. The goldfinch, for
instance, is far more pugnacious than the linnet, and the
blackbird than the thrush. Those birds which undergo a

seasonal change of plumage likewise become much more

pugnacious at the period when they are most gayly orna-
mented. No doubt tin; males of some obscurely oolored
birds light desperately together, but it appears that when

sexual selection has been highly influential, and has given

;><>

SEXUAL SELECTION: BIRDS.

[Part II.

bright colors 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 mam-
mals. On the other hand, with birds the power of song
and brilliant colors have rarely been both acquired by the
males of the same species ; but in this case, the advantage
gained would have been identically the same, namely, suc-
cess in charming the female. Nevertheless, it must be
owned that the males of several brilliantly-colored 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 orna-
mented in any very high degree, but which nevertheless
display, during their courtship, whatever attractions they
may possess. These cases are in some respects moil
curious than the foregoing, and have been but little no-
ticed. I owe the following facts, selected from a large
body of valuable notes, sent to me by Mr. Jenner Weir,
who has long kept birds of many kinds, including all «the
British Fringillida3 and Emberizidae. The bullfinch makes
his advances in front of the female, and then puft's 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 chaflinch also stands in
front of the female, thus showing his red breast, and
" blue-bell," as the fanciers call his head ; the wings at the
same time being slightly expanded, with the pure white
bands on the shoulders thus rendered conspicuous. The
common linnet distends his rosy breast, slightly expands
his brown wings and tail, so as to make the best of them
by exhibiting their white edgings. We must, however,
be cautious in concluding that the wings are spread out

Chap. XIII.] DISPLAY BY THE MALE.

91

solely for display, as some birds act thus 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. No other
British finch, as Mr. Weir informs me, turns during his
courtship from side to side in this manner ; not even the
closely-allied male siskin, for he would not thus add to his
beauty.

Most of the British Buntings are plain-colored birds ;
but in the spring the feathers on the head of the male
reed-bunting {Emberiza schoeniculus) acquire a fine black
color by the abrasion of the dusky tips ; and these are
erected during the act of courtship. Mr. Weir has kept
two species of Amadina from Australia: the A. castanotis
is a very small and chastely-colored finch, with a dark
tail, white rump, and jet-black upper tail-coverts, each of
the latter being marked with three large conspicuous oval
spots of white.88 This species, when courting the female,
slightly spreads out and vibrates these party-colored t ail-
coverts in a very peculiar manner. The male Amadina
Jjathami behaves very differently, exhibiting before the
female his brilliantly-spotted breast and scarlet rump, and
scarlet upper tail-coverts. I may here add from Dr.
.Terdon, that the Indian Bulbul (J'i/c?ia/to(as ha iimrrhtnts)
lias crimson under tail-coverts, and the beauty of these
feathers, it might be thought, could never be w i ll cxhib-

M For the dcHccipiioii of tlicHf birds, let Gould's * Hand-book t<> ilu«
Btfdl of Australia,' vol i. 1 scr., p. 117.

08

SEXUAL SELECTION: BIRDS. [Part II.

ited ; but the bird " when excited often spreads them out
laterally, " so that they can be seen even from above." 87
The common pigeon has iridescent feathers on the breast,
and every one must have seen how the male inflates his
breast while courting the female, thus showing off these
feathers to the best advantage. One of the beautiful
bronze-winged pigeons of Australia (Ocyphaps lophotes) {
behaves, as described to me by Mr. Weir, very differently :
the male, while standing before the female, lowers his head
almost to the ground, spreads out and raises perpendicu-
larly his tail, and half expands his wings. He then alter-
nately 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 show with
what care male birds display their various charms, and
this they do with the utmost skill. While preening their
feathers, they Jhave 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 instinc-
tive. If so, we ought not to accuse birds of conscious
vanity ; yet when we see a peacock strutting about, with
expanded and quivering tail-feathers, he seems the very
emblem of pride and vanity.

The various ornaments possessed by the males are cer-
tainly of the highest importance to them, for they have
been acquired in some cases at the expense of greatly-im-
peded powers of flight or of running. The African night-
jar (Cosmetomis), which during the pairing-season has
one of its primary wing-feathers developed into a streamer
of extreme length, is thus much retarded in its flight, al-
though at other times remarkable for its swiftness. The

87 1 Birds of India,' vol. ii. p. 96.

Chap. XIII.] DISPLAY BY THE MALE.

93

" unwieldly 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 ex-
tremely long tail-feathers of the male widow-birds (Vidua)
of Southern Africa render " their flight heavy ; 99 but as
soon as these are cast off they fly as well as the females.
As birds always breed when food is abundant, the males
probably do not suffer much inconvenience in searching
for food from their impeded powers of movement; but
there can hardly be a doubt that they must be much more
liable to be struck down by birds of prey. Nor can we
doubt that the long train of the peacock and the long tail
and wing feathers of the Argus pheasant must render
them a more easy prey to any prowling tiger-cat than
would otherwise be the case. Even the bright colors of
many male birds cannot fail to make them conspicuous to
their enemies of all kinds. Hence it probably is, as Mr.
Gould has remarked, that such birds are generally of a
shy disposition, as if conscious that their beauty was a
source of danger, and are much more difficult to discover
or approach, than the sombre-colored and comparatively
tame females, or than the young and as yet unadorned
males.88

It is a more curious fact that the males of some birds
which are provided with special weapons for buttle, and
which in a state of nature are so pugnacious that they
often kill each other, suffer from possessing certain orna-

M On the Cosmetornis, sec Livingstone's 4 Expedition to the Zambesi,'

1865, p. 66. On the Axgui pheasant, Jardlne's 'Nut. Hist. Lib, : Birds,1
vol. xiv. p. 167. On Hints of Paradise, Lesson, by Bream,

4 Thierleben,' IJ. iii. h. 1125. On the widow-bird, Harrow's 1 Travels in
Africa,' vol. i. p. 243, and 4 Ibis,' vol. iii. lH6|,p. i:i:t. Mr. Could on
the shyness of mule birds, 4 Hund-book to Hirds of Australia,' vol i. 1865,
pp. 210, 457.

04

SEXUAL SELECTION: BIRDS.

[Part II.

ments. Cock-fighters trim the hackles and cut off the
comb and gills of their cocks ; and the birds are then said
to be dubbed. An undubbed bird, as Mr. Tegetmeier in-
sists, " is at a fearful disadvantage : the comb and gills
offer an easy hold to his adversary's beak, and as a cock
always strikes where he holds, when once he has seized
his foe, he has him entirely in his power. Even supposing
that the bird is not killed, the loss of blood suffered by an
undubbed cock is much greater than that sustained by
one that has been trimmed." 89 Young turkey-cocks in
fighting always seize hold of each other's wattles ; and I
presume that the old birds fight in the same manner. It
may perhaps be objected that the comb and wattles are
not ornamental, and cannot be of service to the birds in
this way ; but even to our eyes, the beauty of the glossy
black Spanish cock is much enhanced by his white face
and crimson comb; and no one who has ever seen the
splendid blue wattles of the male Tragopan pheasant,
when distended during the act of courtship, can for a mo-
ment doubt that beauty is the object gained. From the
foregoing facts we clearly see that the plumes and other
ornaments of the male must be of the highest importance
to him ; and we further see that beauty in some cases is
even more important than success in battle.

89 Tegetmeier, 'The Toultry-Book,' 18GG, p. 139.

Chap. XIV.l SEXUAL SELECTION : BIRDS.

05

CHAPTER XIV.

Bibbs — continued.

Choice exerted by the Female. — Length of Courtship. — Unpaired Birds. —
Mental Qualities and Taste for the Beautiful. — Preference or Antip-
athy shown by the Female for Particular Males. — Variability of
Birds. — Variations sometimes abrupt. — Laws of Variation. — Formation
of Ocelli. — Gradations of Character. — Case of Peacock, Argus Pheas-
ant, and Urosticte.

When the sexes differ in beauty, in the power of sing-
ing, or in producing what I have called instrumental mu-
sic, it is almost invariably the male which excels the fe-
male. 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, this is always shortly before
the breeding-season. It is the male alone who elaborate-
ly displays his varied attractions, and often perforins
strange antics on the ground or in the air, in the presence
of the female. Each male drives away, or, if he can, kills
all his rivals. Hence we may conclude that it is the
object of the male to induce the female to pair with him,
and for this purpose he tries to excite or charm her in
various ways ; and this is the opinion of all those w ho
have carefully studied the habits of living birds, lint
there remains a question which has an all-important bear-
ing on sexual selection, namely, Does every male of the
same species equally excite and attract the female? or

does she exert a choice, and prefer certain males? Tliis
question can be answered in the affirmative by much di-

96

SEXUAL SELECTION: BIRDS.

[Part II.

rect and indirect evidence. It is much more difficult to
decide what qualities determine the choice of the females j
but here again we have some direct and indirect evidence
that it is to a large extent the external attractions of the
male, though no doflbt his vigor, courage, and other men-
tal qualities, come into play. We will begin with the in-
direct 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 court-
ship being a prolonged affair, and partly on the reitera-
tion of the act of pairing. Thus in Germany and Scandi-
navia the balzens or leks of the Blackcocks last from the
middle of March, all through April into May. As many
as forty or fifty, or even more, birds congregate at the
leks ; and the same place is often frequented during suc-
cessive years. The lek of the Capercailzie lasts from the
end of March to the middle or even end of May. In
North America " the partridge-dances " of the Tetrao
phasianellm " last for a month or more." Other kinds of
grouse both in North America and Eastern Siberia1 fol-
low nearly the same habits. The fowlers discover the
hillocks where the Ruffs congregate by the grass being
trampled bare, and this shows 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 full-plu-
maged male Birds of Paradise congregate. In this latter

1 Nordmann describes (' Bull Soc. Imp. des Nat. Moscow,' 1801, tome
xxxiv. p. 204) the balzen of Tetrao urogalloicUs in Amur Land. He esti-
mated the number of assembled males at above a hundred, the females,
which lie hid in the surrounding bushes, not being counted. The noises
uttered differ from those of the T. urogallu* or the capercailzie.

Chap. XIV.]

LENGTH OF COURTSHIP.

or

case it is not expressly stated that the females meet on
the same trees, but the hunters, if not specially asked,
would not probably mention their presence, as their skins
are valueless. Small parties of an African weaver (Plo-
cens) congregate, during the breeding-season, and perform
for hours their graceful evolutions. Large numbers of
the Solitary snipe (Scolopax major) assemble during the
dusk in a morass;- and the same place is frequented for
the same purpose during successive years ; here they may
be seen running about " like so many large rats," puffing
out their feathers, flapping their wings, and uttering the
strangest cries.2

Some of the above-mentioned birds, namely, the black-
cock, capercailzie, pheasant-grouse, the ruff, the Solitary
snipe, and perhaps some others, are, as it is believed, po-
lygamists. With such birds it might have been thought
that the stronger males would simply have driven away
the weaker, and then at once have taken possession of as
many females as possible; but if it be indispensable for
the male to excite or please the female, we can understand
the length of the courtship and the congregation of so
many individuals of both sexes at the same. spot. Certain
species which are strictly monogamous likewise hold nup-
tial assemblages; this seems to be the case in Scandinavia
with one of the ptarmigans, and their Leka last from the
middle of March to the middle of May. In Australia the
lyre-bird or Mt'ioira xu)><rl><( Conns " small round hillocks,"
and the M. Albert i serai dies for it sell" shallow holes, or, as
they are called by the natives, corrobon/imj-jrinas, where

9 With respect to the assemblages of the nbove-naine<l grouse, see
Hielmi, 'Thtateben,' B. Iy. h. 860; also L. Uoyd, 'Game-Birda of Bwe-
lien,' 1867, pp. 19,78. Richardson, 'Fauna Bor. Americana,' Birds, p.

302. References in regard to tin- assemblages of otln t l ii <ls have pro-

vioiinly been gWon. On Paradlsea, lee Wallace, in ' Annals ind Ifag. of
Nut. Hist.' vol. >x. isr.7, p. 419. on the anlne, Lloyd, Ibid, p. 181,

38

SEXUAL SELECTION: BIRDS.

[Paut II.

it is believed both sexes assemble. The meetings of the
M. superba are sometimes very large ; and an account has
lately been published3 by a traveller, who heard in a val-
ley beneath him, thickly covered with scrub, " a din which
completely astonished " him ; on crawling onward he be-
held to his amazement about one hundred and fifty of the
magnificent lyre-cocks, "ranged in order of battle, and
fighting with indescribable fury." The bowers of the
Bower-birds are the resort of both sexes during the
breeding-season ; and " here the males meet and contend
with each other for the favors 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 informed by the Rev. W. Darwin Fox, used to as-
semble from all parts of Delamere Forest, in order to
celebrate the " great magpie marriage." Some years ago
these birds abounded in extraordinary numbers, so that a
gamekeeper killed in one morning nineteen males, and
another killed by a single shot seven birds at roost together.
While they were so numerous, they had the habit very
early in the spring of assembling at particular spots, where
they could be seen in flocks, chattering, sometimes fight-
ing, bustling and flying about the trees. The whole aflair
was evidently considered by the birds as of the highest
importance. Shortly after the meeting they all separated,
and were then observed by Mr. Fox and others to bo
paired lor the season. In any district in which a species
does not exist in large numbers, great assemblages cannot,
of course, be held, and the same species may have differ-
ent habits in different countries. For instance, I have

8 Quoted by Mr. T. W. Wood in the 'Student,' April, 1870, p. 125.
4 Gould, 1 Hand-book of Birds of Australia,' voL i. pp. 300, 308, 448
451. On the ptarmigan, above alluded to, see Lloyd, ibid. p. 129.

Chap. XIV.] UNPAIRED BIRDS.

99

never met with any account of regular assemblages of
black game in Scotland, yet these assemblages are so well
known in Germany and Scandinavia that they have spe-
cial names.

Unpaired Birds. — From the facts now given, we may
conclude that with birds belonging to widely-different
groups their courtship is often a prolonged, delicate, and
troublesome affair. There is even reason to suspect, im-
probable 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 in consequence 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 fre-
quently with the magpie than with any other bird, owing
perhaps to its conspicuous appearance and nest. The
illustrious Jenner states that in Wiltshire one of a pair
was daily shot no less than seven times successively, " but
all to no purpose, for the remaining magpie soon found
another mate ; " and the last pair reared their young. A
new partner is generally found on the succeeding day ;
but Mr. Thompson gives the case of one being replaced
on the evening of the same day. Even after the eggs are
hatched, if one of the old birds is destroyed, a mate will
often be found ; this occurred after an Interval of two days,
in a case recently observed by one of Sir J. Lubbock's
keepers.6 The first and most obvious conjecture is, that
male magpies must be much more numerous than the fe-
males; and that in the above eases, as well as in many oth-
ers which could be given, tin? males alone had been killed.

This apparently holds good in some instances, for the

8 On magpies, .Tenner, in ' IMiil. Transact. 1 1824, p. 11. IftOgtlUrmy,
•Hist. British Birds,1 vol. i. p, :>7<>. Thompson, in ' Anna!- ami Ma;', of
Nut. IliHt.' vol. viii. IN 12, p. I'.M.

100

SEXUAL SELECTION: BIRDS.

[Part II.

game-keepers in Dclamere Forest assured Mr. Fox that
the magpies ami 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 be-
ing easily killed while bringing food to the sitting females.
Macgillivray, however, gives, on the authority of an ex-
cellent observer, an instance of three magpies successively
killed on the same nest, which were all females ; and an-
other case of six magpies successively killed while sitting
on the same eggs, which renders it probable that most of
them were females, though the male will sit on the eggs,
as I hear from Mr. Fox, when the female is killed.

Sir J. Lubbock's game-keeper has repeatedly shot, but
how many times he could not say, one of a pair of jays
((larruhis (/htmdtrtus), and has never failed shortly after-
ward to find the survivor reniatched. The Rev. W. D.
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 com-
mon ; but the peregrine falcon (Falco peregrintuf) is rare,
yet Mr. Thompson states that in Ireland " if either an old
male or female be killed in the breeding-season (not an
uncommon circumstance), another mate is found within a
very few days, so that the eyries, notwithstanding such
casualties, are sure to turn out their complement of young."
Mr. Jenner Weir has known the same thing to occur with
the peregrine falcons at Beach y Head. The same observer
informs me that three kestrels, all males (Falco tinnuncu-
were killed one after the other while attending the
same nest; two of these were in mature plumage, and 4 he
third in the plumage of the previous year. Even with the
rare golden eagle (Aquila chrysatttos), Mr. Birkbeck was
assured hv :i trustworthy game-keeper in Scotland, that if
one is killed, another is soon found. So with the white
owl (Strix flammea), it has been observed that " the sur-

Chap. XIV.]

UNPAIRED BIRDS.

101

vivor 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 par-
tridges when paired were disturbed by the males fighting,
used to shoot them ; and, though he had widowed the
same female several times, she was always soon provided
with a fresh partner. This same naturalist ordered the
sparrows, which deprived the house-martins of their nests,
to be shot: but the one which was left, "be it cock or
hen, presently procured a mate, and so for several times
following." I could add analogous cases relating to the
chaffinch, nightingale, and redstart. With respect to the
latter bird ( Phcenicura ruticilla), the writer remarks that
it was by no means common in the neighborhood, and he
expresses much surprise how the sitting female could so
soon give effectual notice that she was a widow. Mr.
Jenner Weir lias 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
far from loud. I will give only one other fact, on the
authority of this same observer; one of a pair of starlings
{Stumus vulgaris) was shot in the morning ; by noon a
new mate was found; this was again shot , bat before
night the pair was complete; so that the disconsolate
widow or widower was thrice consoled (lining the same
day. Mr. Engleheart also informs me that, he used dur-
ing several years to shoot one of a pair of Starling! which
built in a hole in a house al IMackh- at h ; Imt t lie 1- »-s was

always immediately repaired. During ono season ho

kept an aOCOUnt an. I found that he had Bhot thirty tiw

birds from the sa nest ; these consisted of both males

and females, but in what proportion he oould not tai i

102

SEXUAL SELECTION: BIRDS.

[Part II.

nevertheless after all this destruction, a brood was
reared.6

These facts are certainly remarkable. How is it that
so many birds are ready immediately to replace a lost
mate ? Magpies, jays, carrion-crows, partridges, and
some other birds, are never seen during the spring by
themselves, and these offer at first sight the most perplex-
ing case. But birds of the same sex, although of course
not truly paired, sometimes live in pairs or in small par-
ties, as is known to be the case with pigeons and par-
tridges. Birds also sometimes live in triplets, as has been
observed with starlings, carrion-crows, parrots, and par-
tridges. 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. The males of certain birds may occasion-
ally be heard pouring forth their love-song long after the
proper time, showing that they have either lost or never
gained a mate. Death from accident or disease of either
one of a pair, would leave the other bird 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 in-
duced 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.T Such con-

6 On the Peregrine falcon see Thompson, 1 Nat. Eist. of Ireland :
Birds,' vol. L 1849, p. 39. On owls, sparrows, and partridges, see White,
1 Nat Hist, of Selborne,' edit, of 1825, vol. i. p. 139. On the Phcenicura,
see Loudon's 4 Mag. of Nat. Hist.' voL viL 1834, p. 245. Brehm (' Thier-
lebcn,' B. iv. s. 991) also alludes to cases of birds thrice mated during
same day.

1 See White ('Nat. Hist, of Selborne,' 1825, vol. i. p. 140) on the ex-
istence, early in the season, of small coveys of male partridges, of which
fact I have heard other instances. See Jenner, on the retarded state of

Chap. XIV.]

MENTAL QUALITIES.

103

tingencies as these probably explain most of the foregoing
cases.8 Nevertheless it is a strange fact that within the
same district, during the height of the breeding-season,
there should be so many males and females always ready
to repair the loss of a mated bird. Why do not such
spare birds immediately pair together? Have we not
some reason to suspect, and the suspicion has occurred to
Mr. Jenner Weir, that inasmuch as the act of courtship
appears to be with many birds a prolonged and tedious
affair, so it occasionally happens that certain males and
females do not succeed, during the proper season, in ex-
citing 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 fe-
male birds occasionally evince toward particular males.

Mental Qualities of Birds and their Taste for tJie
Beautiful. — Before we discuss any further the question
whether the females select the more attractive males, or

the generative organs in certain birds, in ' PhiL Transact.' 1824. In re-
gard to birds living in triplets, I owe to Mr. Jenner Weir the cases of
the starling and parrots, and to Mr. Fox, of partridges ; on carrion-crows,
see the 'Field,' 1808, 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. 8, 1868) by
the Rev. F. 0. Morris, on the authority of the Hon. and Kev. (>. \V. For-
ester. "The game-keeper here found a hawk's nest this year, with B.Ye
young ones in it. He took four and killed them, but left one w ith its
wings clipped as a decoy to destroy the old ones by. They were both
shot next day in the act of feeding the young one, and the keeper thought
It was done with. The next day he came again and found two Othei
charitable hawks, who had conic; with an adopted feeling to lUOCOf the
Orphan. These two he killed, and then left the ne-t. <»n returning •£
tcrward he found two more charitable individual- on the same errand of

mercy. One of these he killed; the other be also shot, but could not

find. No more came on the like fruitlesH errand."

104

SKXl'AL SKM-CTION : BIRDS.

[Pakt II

accept the first whom they may encounter, it will be ad-
visable briefly to consider the mental powers of birds.
Their reason is generally, and perhaps justly, ranked as
low; yet some facts could be given9 leading to an oppo-
site conclusion. Low powers of reasoning, however, are
compatible, as we see with mankind, with strong affec-
tions, acute perception, and a taste for the beautiful ; and
it is with these latter qualities that we arc here concerned.
It has often been said that parrots become so deeply at-
tached to each other that when one dies the other for a
longtime pines; but Mr. .Tenner 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 afterward uttering a plaintive call ; and Mr. St. John
gives10 various facts proving the attachment of mated
birds. Starlings, however, as we have seen, may be con-
soled thrice in the same day for the loss of their mates.
In the Zoological Gardens parrots have clearly recognized
their former masters after an interval of some months.
Pigeons have such excellent local memories that they
have been known to return to their former homes after an
interval of nine months, yet, as I hear from Mr. Harrison
Weir, if a pair which would naturally remain mated for
life be separated for a few weeks during the winter and
matched with other birds, the two, when brought together
again, rarely, if ever, recognize each other.

Birds sometimes exhibit benevolent feelings ; they will

9 For instance, Mr. Yarrell states (' Hist British Birds/ vol iii. 1845,
p. 585) that a gull was not able to swallow a small bird which had been
given to it. The gull " paused for a moment, and then, as if suddenly
recollecting himself, ran off at full speed to a pan of water, shook the
bird about in it until well soaked, and immediately gulped it down.
Since that time he invariably has had recourse to the same expedient in
similar cases."

10 'Tour in Rutherlandshire,' vol. i. 1849, p. 185.

Chap. XIV.]

MENTAL QUALITIES.

105

feed the deserted young even of distinct species, but this
perhaps ought to be considered as a mistaken instinct.
They will also feed, as shown in an earlier part of this
work, adult birds of their own species which have become
blind.. Mr. Buxton gives a curious account of a parrot
which took care of a frost-bitten and crippled bird of a
distinct species, cleansed her feathers and defended her
from the attacks of the other parrots which roamed freely
about his garden. It is a still more curious fact that
these birds apparently evince some sympathy for the
pleasures of their fellows. When a pair of cockatoos
made a nest in an acacia-tree, " it was ridiculous to see
the extravagant interest taken in the matter by the others
of tne same species." These parrots, also, evinced un-
bounded curiosity, and clearly had "the idea of property
and possession." 11

Birds possess acute powers of observation. Every
mated bird, of course, recognizes its fellow. Audubon
states that with the mocking-thrushes of the United States
(Mimus polyglottus) a certain number remain all the year
round in Louisiana, while the others migrate to the East-
ern States; these latter, on their return, are instanth
recognized, and always attacked, by their Southern breth-
ren. Birds under confinement distinguish different per-
sons, as is proved by the strong and permanent antipathy
or affection which they show, without any apparent cause,

toward certain individuals. 1 have heard of numerous
instanoes with jays, partridges, canaries, and especially
bullfinches. Mr. Hussy has described in how extraordi-
nary a manner a tame partridge recognized everybody;

and its likes and dislikes were very strong. This bird
seemed Mfbnd of gay colors, and no \\v\\ gown or cap

11 Acclimatization of PurrotM,1 In »'. |tu vion, M l". ' Annal imJ
Mug. of Nut. Hi t.' Nor. 1868, p, B81.

10G

SEXUAL SELECTION: BIRDS.

[Part II.

could be put on without catching his attention." 13 Mr.
Hewitt has carefully described the habits of some ducks
(recently descended from wild birds), which, at the ap-
proach of a strange dog or cat, would rush Headlong into
the water, and exhaust themselves in their attempts to es-
cape ; but they knew so well Mr. Hewitt's own dogs and
cats 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 afterward 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 mutu-
ally recognized each other as old friends.13

Mr. Jenner Weir is convinced that birds pay particu-
lar attention to the colors of other birds, sometimes out of
jealousy, and sometimes as a 6ign of kinship. Thus he
turned a reed-bunting (Emberiza schamiculus), which had
acquired its black head, 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 com-
rades, 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. Mr. Weir was also obliged to turn out a robin,
as it fiercely attacked all birds with any red in their plu-
mage, but no other kinds ; it actually killed a red-breasted

" ■ The Zoologist,' 1847-1848, p. 1602.

13 Ilewitt on wild ducks, 'Journal of Horticulture,' Jan. 13, 18G3, p.
39. Audubon on the wild-turkey, 'Ornith. Biography,' vol. i. p. 14. On
the mocking thrush, ibid. vol. L p. 110.

Chap. XIV.] TASTE FOR THE BEAUTIFUL.

107

crossbill, and nearly killed a goldfinch. On the other
hand, he has observed that some birds, when first intro-
duced into his aviary, fly toward the species which re-
semble them most in color, and settle by their sides.

As male birds display with so much care their fine
plumage and other ornaments in the presence of the fe-
males, it is obviously probable that these appreciate the
beauty of their suitors. It is, however, difficult to obtain
direct evidence of their capacity to appreciate beauty.
When birds gaze at themselves in a looking-glass ( of
which many instances have been recorded) we cannot feel
sure that it is not from jealousy at a supposed rival,
though this is not the conclusion of some observers. In
other cases it is difficult to distinguish between mere curi-
osity and admiration. It is perhaps the former feeling
which, as stated by Lord Lilford,14 attracts the Ruff
strongly toward any bright object, so that, in the Ionian
Islands, it " will dart down to a bright-colored handker-
chief, 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 outside of their nests "with the utmost taste; they
instinctively fasten thereon beautiful pieces of fiat lichen,
the larger pieces in the middle, and the smaller on the part
attached to the branch. Now ami then a pretty feather
is intertwined or fastened to the outer sides, the Btem
being always so placed that the feather stands out beyond
the surface." The best evidence, however, of a taste for
the beautiful is afforded l>y the three genera of Australian
bower-birds already mentioned Thoir bowers (see Fig,

' ' Thl ' ll)iV vol. ii. i860, |». p I I.

108

SEXUAL SELECTION: BIRDS.

[Part II.

46, p. 07), where the sexes congregate and play strange
antics, are differently constructed, but what most concerns
us is, that they are decorated in a different manner by the
several species. The Satin bower-bird collects gayly-col-
ored 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 rearranged, and carried about
by the birds while at play. The bower of the Spotted
bower-bird " is beautifully lined with tall grasses, so dis-
posed that the heads nearly meet, and the decorations are
very profuse." Round stones arc 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 de-
scribed by Mr. Ramsay, ornaments its short bower with
bleached land-shells belonging to five or six species, and
with " berries of various colors, blue, red, and black, which
give it when fresh a very pretty appearance. Besides
these there were several newly-picked leaves and young
shoots of a pinkish color, the whole showing a decided
taste for the beautiful." Well may Mr. Gould say " 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 species
certainly differs.16

Preference for Particular Males by the Females. —
Having made these preliminary remarks on the discrimi-

16 On the ornamented nests of humming-birds, Gould, 1 Introduction
to the Trochilidae, 1861, p. 19. On the bower-birds, Gould, 'Hand-book
to the Birds of Australia,' 1865, vol i. pp. 441-461. Mr. Ramsay in the
'Ibis,' 1867, p. 456.

Chap. XIV.] P PREFERENCE BY THE FEMALE.

109

nation and taste of birds, I will give all the facts known
to me, which bear on the preference shown 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 Macgil-
livray relates how a male blackbird and female thrush
"fell in love with each other," and produced offspring.16
Several years ago eighteen cases had been recorded of
the occurrence in Great Britain of hybrids between the
black grouse and pheasant ; 17 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 some-
times 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, be-
longing to distinct species, which have become absolutely
fascinated with each other, although living with their own
species. Thus Waterton 18 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 Wig-
eon (Mareca penclope), living with females of the same
species, has been known to pair with a Pintail duck, Qw r-
quedula acuta. Lloyd describes the remarkable attach-
ment between a shield-drake {Tadorna vuIjhoi* r) and a
common duck. Many additional instances could be given ;
and the Rev. E. S. Dixon remarks that "those who have

18 'Hint, of British Birds,' vol. ii. p.
11 'Zoologist,' 1858-1854, p. 3946.

18 Waterton, 'Kssays on Nut. Hist.' 2d series, pp. 42, 117. For the
following statements, sec, on tho wigeon, Loudon's ' Hag. of Nat Hi><.'
vol. ix. p. ()l»i; I,. Lloyd, 'Scandinavian Advcul arcs,' vol. i. L854, p. 159 j

Dixon, 1 Ornamental and Domestic Poultry,' p. 137; Hewitt, in * Journal
of Horticulture,' .Jan. L!, isr.:i, p. lo; Itcchstcin, ' StuK'nTOgeV Is'".
B. 230.

no

SEXUAL SELECTION: BIRDS.

[Part II.

kept many different species of geese together, well know
what unaccountable attachments they are frequently form-
ing, and tli at 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 6ame time a pair of Chinese geese (Anser cygnoides)y
and a common gander with three geese. The two lots
kept quite separate, until the Chinese gander seduced one
of the common geese to live with him. Moreover, of the
young birds hatched from the eggs of the common geese,
only four were pure, the other eighteen proving hybrids ;
so that the Chinese gander seems to have had prepotent
charms over the common gander. I will give only one
other case \ Mr. Hewitt states that a wild-duck, reared in
captivity, " after breeding a couple of seasons with her own
mallard, at once shook him off on my placing a male Pin-
tail 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. Color,
however, sometimes comes into play ; for in order to raise
hybrids from the siskin (Fringilla spinus) and the canary,
it is much the best plan, according to Bechstein, to place
birds of the same tint together. Mr. Jenner Weir turned
a female canary into his aviary, where there were male
linnets, goldfinches, siskins, greenfinches, chaffinches, and
other birds, in order to see which she would choose ; but
there never was any doubt, and the greenfinch carried the
day. They paired and produced hybrid offspring.

Chap. XIV.] PREFERENCE BY THE FEMALE.

Ill

With the members of the same species the fact of the
female preferring to pair with one male rather than with
another is not so likely to excite attention, as when this
occurs "between distinct species. Such cases can best be
observed with domesticated or confined birds ; but these
are often pampered by high feeding, and sometimes have
their instincts vitiated to an extreme degree. Of this lat-
ter fact I could give sufficient proofs with pigeons, and
especially with fowls, but they cannot be here related.
Vitiated instincts may also account for some of the hybrid
unions above referred to ; 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 oppor-
tunity for exerting a choice, as she is almost invariably
pursued by many males. Audubon — and we must remem-
ber 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 shown for one."
The female of the red-winged starling (Agelccus phoenice-
us) is likewise pursued by several males, " until, becoming
fatigued, she .alights, receives their addresses, and soon
makes a choice." lie describes also how several" male
night-jars repeatedly plunge through '.lie air with as-
tonishing rapidity, suddenly turning, and thus making a
singular noise ; " hut no sooner has the female made Q6I
choice, than the other males are driven away." With mm
of the vultures (Catharfra <inr<t) of the l'ni led States,

112

SEXUAL SELECTION: BIRDS. [Part II.

parties of eight or ten or more males and females assem-
ble 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 care-
fully observed the wild flocks of Canada geese (Anser
Canadensis), and gives a graphic description of their
love-antics ; he says that the birds which had been pre-
viously mated " renewed their courtship as early as the
month of January, while the others would be contend-
ing or coquetting for hours every day, until all seemed
satisfied with the choice they had made, after which, al-
though they remained together, any person could easily
perceive that they were careful to keep in pairs. I have
observed also that the older the birds, the shorter were
the preliminaries of their courtship. The bachelors and
old maids, whether in regret or not caring to be disturbed
by the bustle, quietly moved aside and lay down at some
distance from the rest." 19 Many similar statements with
respect to other birds could be cited from this same ob-
server.

Turning now to domesticated and confined birds, I
will commence by giving what little I have learned re-
specting the courtship of fowls. I have received long let-
ters on this subject from Messrs. Hewitt and Tegetmeier,
and almost an essay from the late Mr. Brent. It will be
admitted by every one that these gentlemen, so well
known from their published works, are careful and expe-
rienced observers. They do not believe that the females
prefer certain males on account of the beauty of their plu-
mage ; but some allowance must be made for the artificial
state under which they have long been kept. • Mr. Teget-
meier is convinced that a game-cock, though disfigured
by being dubbed with his hackles trimmed, would be ac-

19 Audubon, 'Ornitholog. Biography,' vol. i. pp. 191, 349; vol. ii. pp
i2, 275 ; vol iii. p. 2.

Chap. XIV.] PREFERENCE BY THE FEMALE.

113

cepted as readily as a male retaining all his natural orna-
ments. 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 fe-
male almost invariably prefers the most vigorous, defiant,
and mettlesome male ; hence it is almost useless, as he re-
marks, " 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 in-
forms me, dislike strange males, and will not yield until
well beaten into compliance. Ferguson, however, de-
scribes how a quarrelsome hen was subdued by the gentle
courtship of a Shanghai cock.20

There is reason to believe that pigeons of both sexes
prefer pairing with birds of the same breed ; and dove-
cot-pigeons dislike all the highly improved breeds.21 Mr.
Harrison Weir has lately heard from a trustworthy ob-
server, who keeps blue pigeons, that these drive away all
other colored varieties, such as white, red, and yellow ;
and from another observer, that a female dun carrier
could not be matched, after repeated trials, witli a black
male, but immediately paired with a dun. Generally col-
or alone appears to have little influence on the pairing of
pigeons. Mr. Tegetmeier, at my request, Stained some

20 'Rare and Prize Poultry,' 1854, i>. '27.

81 ' The Variation of Animals and Plants under Domestication,1 rol ii.

p. 103.

114

SEXUAL SELECTION : BIRDS.

[Pakt II.

of his birds with magenta, but they were not much no-
ticed by the others.

Female pigeons occasionally feel a strong antipathy
toward certain males, without any assignable cause.
Thus MM. Boitard and Corbi6, whose experience ex-
tended over forty-five years, state : " Quand une femelle
6prouve de Pantipathie pour un male avec lequel on veut
Paccoupler, malgrd tous les feux de Pamour, malgre Pal-
piste et le chenevis dont on la nourrit pour augmenter son
ardeur, malgre un emprisonnement de six mois et meme
d'un an, elle refuse constamment ses caresses ; les avances
emprcssees, les agaceries, les tournoiemens, les tendres
roucoulemens, rien ne peut lui plaire ni Pemouvoir ; gonflee,
boudeuse, blottie dans un coin de sa prison, elle n'en sort
que pour boire et manger, ou pour repousser avec une
espece de rage des caresses devenues trop pressantes." "
On the other hand, Mr. Harrison Weir has himself ob-
served, and has heard from several breeders, that a female
pigeon will occasionally take a strong fancy for a particu-
lar male, and will desert her own mate for him. Some
females, according to another experienced observer, Rie-
del," are of a profligate disposition, and prefer almost any
stranger to their own mate. Some amorous males, called
by our English fanciers " gay birds," are so successful in
their gallantries, that, as Mr. II. Weir informs me, they
must be shut up, on account of the mischief which they
cause.

Wild-turkeys in the United States, according to Au-
dubon, " sometimes pay their addresses to the domesti-
cated females, and are generally received by them with

22 Boitard and Corbi6, 'Les Pigeons,' 1824, p. 12. Prosper Lucas
(' Trait6 de lTIer6d. Nat.' tome ii. 1850, p. 296) has himself observed
nearly similar facts with pigeons.

,3 1 Die Taubenzucht,' 1824, s. 86.

Chap. XIV.] PREFERENCE BY THE FEMALE.

115

great pleasure." So that these females apparently prefer
the wild to their own males.24

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 pea-
cock. 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 trellis-walls of his
prison, and would not suffer a japanned peacock to touch
them. On his being let out in the autumn, the oldest of
the hens instantly courted him, and was successful in her
courtship. The next year he was shut up in a stable, and
then the hens all courted his rival." 25 This rival was a
japanned or black-winged peacock, which to our eyes is a
more beautiful bird than the common kind.

Lichtenstein, who was a good observer and had excel-
lent opportunities of observation at the Cape of Good
Hope, assured Rudolphi that the female widow-bird
(Chera progne) disowns the male, when robbed of the
long tail-feathers with which he is ornamented during the
breeding-season. I presume that this observation must
have been made on birds under confinement.20 Here is
another striking case ; Dr. Jaeger,27 director of the Zoo-
logical Gardens of Vienna, states that a male silver-pheas-
ant, who had been triumphant over the other males and
was the accepted lover of the females, had his ornamental
plumage spoiled. He was then immediately superseded

24 ( Ornithological Biography,1 vol. i. p. 1".

26 ' Froc. Zool. Soc' 18155, p. 64, The japanned peacock la consid«

cred by Mr. Sclatcr as a distinct species, and has been named PoVO <■'-
gri]>rnni*.

28 Rudolphi, 'Beytr&ge zur Anthropologfe,' 1812, b, L84.
87 'Die Daruin'sclie Thcorie, nnd ihre Stellung zu Moral nnd Keligion,'
18C9, s. 59.

116 SEXUAL SELECTION: BIRDS. [Part II.

by a rival, who got the upper hand and afterward led the
flock.

Not only does the female exert a choice, but in some
few cases she courts the male, or even fights for his pos-
session. 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 caper-
cailzie, the females flit round the male, while he is parad-
ing at one of the places of assemblage, and solicit his
attention.28 We have seen that a tame wild-duck seduced
after a long courtship an unwilling Pintail drake. Mr.
Bartlett believes that the Lophophorus, like many other
gallinaceous birds, is naturally polygamous, but two
females cannot be placed in the same cage with a male, as
they fight so much together. The following instance ot
rivalry is more surprising as it relates to bullfinches, which
usually pair for life. Mr. Jenner Weir introduced a dull-
colored and ugly female into his aviary, and she immedi-
ately attacked another mated female so unmercifully that
the latter had to be separated. The new female did all
the courtship, and was at last successful, for she paired
with the male; but after a time she met with a just re-
tribution, for, ceasing to be pugnacious, Mr. Weir replaced
the old female, and the male then deserted his new and
returned to his old love.

In all ordinary cases the male is so eager that he will
accept any female, and does not, as far as we can judge,
prefer one to the other ; but exceptions to this rule, as we
shall hereafter see, apparently occur in some few groups.
With domesticated birds, I have heard of only one case in

88 In regard to peafowl, sec Sir R. Heron, 'Proc. Zoolog. Soc.' 1835,
p. 54, and the Rev. E. S. Dixon, « Ornamental Poultry,' 1848, p. 8. For
the turkey, Audubon, ibid. p. 4. For the caporcailzie, Lloyd, 4 Game-
Birds of Sweden,' 1867, p. 23.

Chap. XIV.] PREFERENCE BY THE FEMALE.

117

which the males show any preference for particular fe-
males, 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 color, but is most " capricious in his
attachments." 29 From some inexplicable cause he shows
the most determined aversion to certain hens, which no
care on the part of the breeder can overcome. Some hens,
as Mr. Hewitt informs me, 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
outkof forty or fifty will prove fertile. On the other hand,
witli the Long-tailed duck (Harelda glacialis), "it has
been remarked," says M. Ekstrom, " that certain females
are much more courted than the rest. Frequently, indeed,
one sees an individual surrounded by six or eight amorous
males." Whether this statement is credible, 1 know not;
but the native sportsmen shoot these females in order to
stuff them as decoys.30

! With respect to female birds feeling a preference for
particular males, we must bear in mind that we can judge
of choice being exerted, only by placing ourselves in
imagination in the same position. If an inhabitant of
another planet were to behold a number of young rustics
at a fair, courting and quarrelling over a pretty girl, like
birds at one of their places of assemblage, he would be
able to infer that she had the power of choice only by nl>-
serving the eagerness of the wooers to please her, and to
display their finery. Now with birds, the evidence Mauds

thus; they have acute powers <>|* observation, an,d they

39 Mr. Hewitt, quotod in ' TcRctim'icr'rt Poult n Hook,' ls<;c,|>. h',5
» Quoted in l,l.»_vd's 1 Garoe-Birdi of Sweeten,1 p. 845.

118

SEXUAL SELECTION: BIRDS.

[Part II.

seem to have some taste for the beautiful both in color
and sound. It is certain that the females occasionally ex-
hibit, from unknown causes, the strongest antipathies and
preferences for particular males. "When the sexes differ
in color or in other ornaments, the males -with rare excep-
tions are the most highly decorated, either permanently
or temporarily during the breeding-season. They sedu-
lously display their various ornaments, exert their voices,
and perform strange antics in the presence of the females.
Even well-armed males, who, it might have been thought,
would have altogether depended for success on the law of
battle, are in most cases highly ornamented ; and their
ornaments have been acquired at the expense of some loss
of power. In other cases ornaments have been acquired,
at the cost of increased risk from birds and beasts of prey.
With various species many individuals of both sexes con-
gregate 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 pairing.

"What, then, are we to conclude from these facts and
considerations ? Does the male parade his charms with
so much pomp and rivalry for no purpose ? Are we not
justified in believing that the female exerts a choice, and
that she receives the addresses of the male who pleases
her most ? It is not probable that she consciously delib-
erates ; 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
color; that the peahen, for instance, admires each detail
in the gorgeous train of the peacock — she is probably
struck only by the general effect. Nevertheless, after hear-
ing 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,

Chap. XIV.]

VARIABILITY.

119

how the male goldfinch alternately displays his gold-be-
spangled 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 the analogy of our own minds; and the mental
powers of birds, if reason be excluded, do not fundamen-
tally differ from ours. From these various considerations
we may conclude that the pairing of birds is not left to
chance ; but that those males, which are best able by their
various charms to please or excite the female, are under
ordinary circumstances accepted. If this be admitted,
there is not much difficulty in understanding how male
birds have gradually acquired their ornamental characters.
All animals present individual differences, and as man can
modify his domesticated birds by selecting the individuals
which appear to him the most beautiful, so the habitual or
even occasional preference by the female of the more at-
tractive males would almost certainly lead to their modi-
fication ; and such modifications might in the course of
time be augmented to almost any extent, compatible with
the existence of the species.

Variability of Birds, and especially of their Secondary
Sexual Characters. — Variability and inheritance are the
foundations for the work of selection. That domesticated
birds have varied greatly, ther variations being inherited,
is certain. That birds in a state of nature present indi-
vidual differences is admitted by every one ; and that
they have sometimes been modified into distinct races, is
generally admitted.31 Variations are of two kinds, which

31 According to Dr. Miasms ('Ibis,' vol. ii. 18G0, p. 297), there aro
426 Indubitable species of birds which breed in Europe, besides SO
forms, which are frequently regarded as distinct species. Of t ho latter,
Blasius thinks that only 10 aro really doubtful, and that the other 50
ought to bo united with their nearest allies-, but this .show-; that there
must be a considerable amount of variation with some of our Kuropcan

120

SEXUAL SELECTION: BIRDS.

[Paut II.

insensibly graduate into each other, namely, slight differ-
ences between all the members of the same species, and
more strongly-marked deviations which occur only occa-
sionally. These latter are rare with birds in a state of
nature, and it is very doubtful whether they have often
been preserved through selection, and then transmitted to
succeeding generations.83 Nevertheless, it may be worth
while to give the few cases relating chiefly to color (sim-
ple albinism and melanism being excluded), which I have
been able to collect.

Mr. Gould is well known rarely to admit the existence
of varieties, for he esteems very slight differences as spe-
cific; now he states83 that near Bogota certain humming-
birds belonging to the genus Cynanthus are divided into
two or three races or varieties, which differ from each
other in the coloring of the tail — "some having the whole
of the feathers blue, while others have the eight central
ones tipped with beautiful green." It docs not appear
that intermediate gradations have been observed in this

birds. It is also an unsettled point with naturalists, whether several
North American birds ought to be ranked as specifically distinct from
the corresponding European species.

33 'Origin of Species,' fifth edit. 1869, p. 104. I had always per-
ceived that rare and strongly-marked deviations of structure, deserving
to be called monstrosities, could seldom be preserved through natural
selection, and that the preservation of even highly-beneficial variations
would depend to a certain extent on chance. I had also fully appre-
ciated the importance of mere individual differences, and this led me to
insist so strongly on the importance of that unconscious form of selection
by man, which follows from the preservation of the most valued individ-
uals of each breed, without any intention on his part to modify the char-
acters of the breed. But until I read an able article in the ' North Brit-
ish Review ' (March, 1867, p. 289, el seq.\ which has been of more use to
me than any other Review, I did not see how great the chances were
against the preservation of variations, whether slight or strongly pro-
nounced, occurring only in single individuals.

33 ' Introduct. to the Trochilida?,' p. 102.

Chap. XIV.]

VARIABILITY.

121

or the following cases. In the males alone of one of the
Australian parrakeets " the thighs in some are scarlet, in
others grass-green." In another parrakeet of the same
country " some individuals have the band across the wing-
coverts bright-yellow, while in others the same part is
tinged with red." 34 In the United States some few of the
males of the Scarlet Tanager (Tanagra rubra) have "a
beautiful transverse band of glowing red on the smaller
wing-coverts ; " 36 but this variation seems to be somewhat
rare, so that its preservation through sexual selection
would follow only under unusually favorable circum-
stances. In Bengal the Honey buzzard (Pernis cristata)
has either a small rudimental crest on its head, or none at
all ; so slight a difference, however, would not have been
worth notice, had not this same species possessed in
Southern India " a well-marked occipital crest formed of
several graduated feathers." 36

' The following case is in some respects more interest-
ing : 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 dis-
tinguished ornithologists as a distinct species. The fact
of the pied birds being pursued and persecuted with
much clamor by the other ravens of the island was the
chief cause which led Brtlnnich to conclude thai it was
specifically distinct; but this is now known to be an
error.37

34 Gould, 'Hand-book of Hints of Australia,' vol ii. pp. 82, 68.
"Audubon, » Ornitholog. Hio^rnphy,' I HUH, vol. iv. |>. :tNl>.
MJerdon, 1 Blrda of India,' yoL i. p. 108; and Mr. Blvth, in ' Land
and Water,' 1868, p. 881.

* Qraba, 1 Tagebuoh, Reiienaoh Faro,1 1880, i. 61 54. tfaogQUTf*|

•HiHt. Hritirtli Hints,' vol. iii. p. 746. 'll.is,' vol. \. 1868, p. 469,

25

122

SEXUAL SELECTION: BIRDS,

[Taut II.

In various parts of the northern seas a remarkable
variety of the common Guillemot ( Uria troile) is found ;
and ID Feroe, one out of every five birds, according to
Graba's estimation, consists of this variety. It is charac-
terized3H by a pure white ring round the eye, with a curved
narrow white line, an inch and a half in length, extending
back from the ring. This conspicuous character has caused
the bird to be ranked by several ornithologists as a dis-
tinct species under the name of U. lacrymcuis, 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 aj>-
pear suddenly are often, as I have elsewhere shown,"
transmitted either unaltered or not at alL We thus see
that two distinct forms of the same species may coexist in
the same district, and we cannot doubt that if the one had
possessed any great 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 and driven away l>y their comrades, had been
highly attractive, like the pied peacock before mentioned,
to the common black females, their numbers would have
rapidly increased. And this would have been a case of
sexual selection.

With respect to the slight individual differences which
are common, in a greater or less degree, to all the members
of the same species, we have every reason to believe that
they are by far the most important for the work of selec-
tion. Secondary sexual characters are eminently liable
to vary, both with animals in a state of nature and under
domestication.4' There is also reason to believe, as we

n Graba, ibid. s. 54. Macgillivray, ibid, vol v. p. 327.
M 1 Variation of Animals and Plants under Domestication/ voL ii.
p. 92.

40 On these points see also 4 Variation of Animals and Plants under
Domestication,' vol L p. 253 ; toL ii. pp. 73, 75.

Chap. XIV.]

VARIABILITY.

123

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 favorable for sexual selection.
Whether characters thus acquired are transmitted to one
sex or to both sexes, depends exclusively in most cases, as
I hope to show in the following chapter, on the form of
inheritance which prevails in the groups in question.

It is sometimes difficult to form any opinion whether
certain slight differences between the sexes of birds are
simply the result of variability with sexually-limited in-
heritance, without the aid of sexual selection, or whether
they have been augmented through this latter process. I
do not here refer to the innumerable instances in which
the male displays splendid colors or other ornaments, of
which the female partakes only to a slight degree ; for
these cases are almost certainly due to characters primarily
acquired by the male, having been transferred, in a greater
or less degree, to the female. But what are we to con-
clude with respect to certain birds in which, for instance,
the eyes differ slightly in color in the two sexes ? 41 In
some cases the eyes differ conspicuously; thus with the
storks of the genus Xeriorhynchus those of the male are
blackish-hazel, while those of the females are gamboge-
yellow ; with many hornbills (Buceros), as I hear from
Mr. Blyth," the males have intense crimson, and the fe-
males white eyes. In the Hutu ros biconiix, the hind mar-
gin of the casque and a stripe on the crest of the beak are
black in tin; male, but not so in the female, Are we t<>
suppose that these black marks and the Orimson color of
the eyofl have been preserved or augmented through scv-
ual selection in the males? This is very doubtful; for
Mr. Bartlett ihowed me in the Zoological (iardens that

41 800, for IliHtiiiicc, on tin' ii'ulcs of ii I'odini ami ( lalli. 1 iu ' H»i .'
vol. ii. 1800, |>. 206; and rol v. 1H68, p. 426.

4» Sec uIho .I. i.I..!,, ' Itii.lH of In. I'm, ' vol. i. |.|.. '.'CI - I V

124 SEXUAL SELECTION: BIRDS. [Part II.

the inside of the mouth of this Buceros is black in the
male and flesh-colored in the female ; and their external
appearance of beauty would not be thus affected. I ob-
served in Chili" that the iris in the condor, when about a
year old, is dark-brown, but changes at maturity into yel-
lowish-brown in the male, and into bright red in the female.
The male has also a small, longitudinal, leaden-colored,
fleshy crest or comb. With many gallinaceous birds the
comb is highly ornamental, and assumes vivid colon (lin-
ing the act of courtship; but what are we to think of the
dull-colored comb of the condor, which does not appear to
us in the least ornamental ? The same question may be
asked in regard to various other characters, such as the
knob on the base of the beak of the Chinese goose (A?iser
cygnoides), which is much larger in the male than in the fe-
male. 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 fe-
male, 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 illus-
trated 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 feath-

43 'Zoology of the Voyage of H. M. S. Beagle,' 1841, p. 6.

Chap. XIV.]

VARIABILITY.

125

ers on the head of the male become hackle-shaped, evi-
dently on the principle of correlation; while those on
the head of the female are of the ordinary shape. The
color also of the hackles forming the top-knot of the male,
is often correlated with that of the hackles on the neck
and loins, as may be seen by comparing these feathers in
the Golden and Silver-spangled Polish, the Houdans, and
Creve-cceur breeds. In some natural species we may ob-
serve exactly the same correlation in the colors of these
same feathers, as in the males of the splendid Golden and
Amherst pheasants.

The structure of each individual feather generally
causes any change in its coloring to be symmetrical ; we
see this in the various laced, spangled, and pencilled breeds
of the fowl ; and on the principle of correlation the feathers
over the whole body are often modified in the same man-
ner. We are thus enabled without much trouble to rear
breeds with their plumage marked and colored almost as
symmetrically as in natural species. In laced and spangled
fowls the colored margins of the feathers are abruptly de-
fined; 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 toward their ex-
tremities, which were yellowish-white; but between the
white extremities and the black bases, there \v;is on each
feather a symmetrical, curved zone of dark-brown. In
some instances the shaft of the feather determines the dis-
tribution 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 sur-
rounded by a regular zone of dark-brown, edged with
brownish-white. In these eases we see feathers becoming
symmetrically shaded, like those which give s<» much ele-
gance to the plumage of many natural speciea, I ha\e

126

SEXUAL SELECTION: BIRDS.

[Part II

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 large groups of birds it may be observed
that the plumage is differently colored in each species,
yet that certain spots, marks, or stripes, though likewise
differently colored, are retained by all the species. Anal-
ogous cases occur with the breeds of the pigeon, which
usually retain the two wing-bars, though they may be
colored 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 colored in almost an exactly reversed manner to
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 hav-
ing a white instead of a blue tail, with precisely that
small part black which is white in the parent-species.44

Formation and Variability of the Ocelli or Eye-like
Spots on the Plumage of Birds. — As no ornaments are
more beautiful than the ocelli on the feathers of various
birds, on the hairy coats of some mammals, on the scales
of reptiles and fishes, on the skin of amphibians, on the
wings of many Lepidoptera and other insects, they de-
serve to be especially noticed. An ocellus consists of a
spot within a ring of another color, like the pupil within
the iris, but the central spot is often surrounded by addi-
tional concentric zones. The ocelli on the tail-coverts of
the peacock offer a familiar example, as well as those on
the wings of the peacock-butterfly (Vanessa). Mr. Tri-
men has given me a description of a South African moth

44 Bechstein, 1 Naturgeschichte Deutschlands,' B. iv. 1*795, s. 31, ou a
Bub-variety, of the Monck pigeon.

Chap. XIV.]

OCELLI.

127

(Gynanisa Isis), allied to our Emperor moth, in which a
magnificent ocellus occupies nearly the whole surface of
each hinder wing ; it consists of a black centre, including
a semitransparent 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 at
least with insects has probably been a simple one ; 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, showed me a series of
specimens of our common meadow-brown butterfly (JZip-
parchia Janira) exhibiting numerous gradations from a
simple minute black spot to an elegantly-shaded ocellus.
In a South African butterfly (Cyllo Leda, Linn.) belong-
ing to the same family, the ocelli are even still more vari-
able. In some specimens (A, Fig. 52) large spaces on
the upper surface of the wings are colored black, and in-
clude irregular white marks ; and from this state a com-
plete gradation can be traced into a tolerably perfect (A1)
ocellus, and this results from the contraction of the irreg-
ular blotches of color. 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 (IV). 40 In cases like
these, the development of a perfect ocellus does not re-
quire a long course of variation and selection.

45 Thus woodcut has been engraved from a beautiful drawing, most,
kindly made for me by Mr. Trimen ; see also bis description of the won-
derful amount of variation in the coloration and shape of the wings of

this butterfly, in hie 'Rhopalooera Africa Australia, ' p. L86, Bea al o

an interesting paper by the Kcv..ll. II. lliggina, on the Origin of the

ocelli in the Lepidoptera in the 'Quarterly Journal of S/ience,' July.
1808, p. 325.

128

SEXUAL SELECTION: BIRDS.

[Part II.

With birds and many other animals it seems, from the
comparison of allied species, to follow, 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 ; 48 and something of the same kind may be observed
A a*

Bl B

Fig. 52. — Cyllo leda, Linn., from a drawing by Mr. Trimcn, showing the extreme
range of variation in the ocelli.
A. Specimen, from Mauritius, upper B. Specimen, from Java, upper surface

surface of fore-wing. of hind-wing.

A1. Specimen, from Natal, ditto. B1. Specimen, from Mauritius, ditto.

in the two sexes of the Argus pheasant. However this
may be, appearances strongly favor the belief that, on the
one hand, a dark spot is often formed by the coloring
matter being drawn toward a central point from a sur-
rounding zone, which is thus rendered lighter. And, on
the other hand, that a white spot is often formed by the
color being driven away from a central point, so that it
accumulates in a surrounding darker zone. In either case
an ocellus is the result. The coloring matter seems to be
a nearly constant quantity, but is redistributed, either

46 Jerdon, 'Birds of India,' vol. iii. p. 517.

Chap. XIV.] GRADATION OF CHARACTERS.

129

centripetally or centrifugally. The feathers of the com-
mon guinea-fowl offer a good instance of white spots sur-
rounded by darker zones ; and whenever 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 for-
mation of an ocellus in its simplest state appears to be a
simple affair. By what further steps the more complex
ocelli, which are surrounded by many successive zones of
color, have been generated, I will not pretend to say.
But bearing in mind the zoned feathers of the mongrel
offspring from differently-colored fowls, and the extraor-
dinary variability of the ocelli in many Lepidoptera, the
formation of these beautiful ornaments can hardly be a
highly-complex process, and probably depends on some
slight and graduated change in the nature of the tissues.

Gradation of Secondary Sexual Characters. — Cases
of gradation are important for us, as they show that it is
at least possible that highly-complex ornaments may have
been acquired by small successive steps. In order to dis-
cover the actual steps by which the male of any existing
bird has acquired his magnificent colors or other orna-
ments, we ought to behold the long line of his ancient and
extinct progenitors ; but this is obviously impossible.
We may, however, generally gain a clew by comparing all
the species of a group, if it be a large one ; for some of
them will probably retain, at least in a partial maimer,
(races of their former characters. Instead of entering on
tedious det ails respecting various groups, in which Bt l ik-
ing instances of gradation could be given, it seems the
pest plan to take some one or two strongly-characterized
cases, for instance that of the peacock, in order to dis-
cover if any light can thus he thrown on the stop! by

130

SEXUAL SELECTION: BIRDS.

[Part II.

which this bird has become so splendidly decorated. The
peacock is chiefly remarkable from the extraordinary
length of his tail-coverts; the tail itself not being much
elongated. The barbs along nearly the whole length of
these feathers stand separate or are decomposed ; but this
is the case with the feathers of many species, and with
some varieties of the domestic fowl and pigeon. The
barbs coalesce toward the extremity of the shaft to form
the oval disk or ocellus, which is certainly one of the most
beautiful objects in the world. This consists of an irides-
cent, intensely blue, indented centre, surrounded by a
rich green zone, and this by a broad coppery-brown zone,
and this by five other narrow zones of slightly-different
iridescent shades. A trifling character in the disk per-
haps deserves notice ; the barbs, for a space along one of
the concentric zones are destitute, to a greater or less de-
gree, of their barbules, so that a part of the disk is sur
rounded by an almost transparent zone, which gives to it
a highly - finished aspect. But I have elsewhere de-
scribed *7 an exactly analogous variation in the hackles of
a sub-variety of the game-cock, in which the tips, having
a metallic lustre, " are separated from the lower part of
the feather by a symmetrically-shaped transparent zone,
composed of the naked portions of the barbs." The lower
margin or base of the dark-blue centre of the ocellus is
deeply indented on the line of the shaft. The surround-
ing zones likewise show traces, as may be seen in the
drawing (Fig. 53), of indentations, or rather breaks.
These indentations are common to the Indian and Javan
peacocks (Pavo cristatus and P. muticus) ; and they
seemed to me to deserve particular attention, as probably
connected with the development of the ocellus ; but for a
long time I could not conjecture their meaning.

If we admit the principle of gradual evolution, there

47 ' Variation of Animals and Plants under Domestication,' vol. i. p. 254.

Chap. XIV.] GRADATION OF CHARACTERS. 131

must formerly have existed many species which presented
every successive step between the wonderfully elongated
tail-coverts of the peacock and the short tail-coverts of all
ordinary birds ; and again between the magnificent ocelli
of the former, and the simpler ocelli or mere colored spots

Fia. 53.— Feather of Peacock, about two-thirds of natural pizc, carefully drawn
by Mr. Ford. The transparent zone is represented by the outermost white
zone confined to the upper end of the disk.

of other birds ; :m<l so with the other characters of the
peacock. Let us look to the allied Gallinaceae for any
still-existing gradations. The species and Bub-8peoiei of
Pblyplectron inhabit countries adjacenl to the native land
of the peacock; and they so far resemble this bW that

132

SEXUAL SELECTION: BIRDS.

[Part II.

they are sometimes ealled peacock-pheasants. I am also
informed by Mr. Bartlett that they resemble the peacock
in their voice and in some of their habits. During the
spring the males, as previously described, strut about be-
fore the comparatively plain-colored females, expanding
and erecting their tail and wing feathers, which are orna-
mented with numerous ocelli. I request the reader to
turn back to the drawing (Fig. 51, p. 86) of a Polyplec-
tron. In P. Napoleonis the ocelli are confined to the tail,
and the back is of a rich metallic blue, in which respects
this species approaches the Java peacock. P. IIardwi< h ii
possesses a peculiar top-knot, somewhat like that of this
same kind of peacock. The ocelli on the wings and tail
of the several species of Polyplectron are either circular
or oval, and consist of a beautiful, iridescent, greenish-
blue or greenish-purple disk, with a black border. This
border in P. chinquis shades into brown which is edged
with cream-color, so that the ocellus is here surrounded
with differently, though not brightly, shaded concentric
zones. The unusual length of the tail-coverts is another
highly-remarkable character in Polyplectron ; for in some
of the species they are half as long, and in others two-
thirds of the length of the true tail-feathers. The tail-cov-
erts are ocellated, as in the peacock. Thus the several
species of Polyplectron manifestly make a graduated ap-
proach in the length of their tail-coverts, in the zoning of
the ocelli, and in some other characters, to the peacock.

Notwithstanding this approach, the first species of
Polyplectron which I happened to examine 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. 54), one on
each side of the shaft. Hence I concluded that the early

Chap. XIV.] GRADATION OF CHARACTERS.

133

progenitors of the peacock c
in any degree a Polyplectron.
But on continuing my search,
I observed that in some of the
species the two ocelli stood
very near each other ; that in
the tail-feathers of P. Hard-
wlckii they touched each
other ; and, finally, that in the
tail-coverts of this same spe-
cies as well as of P. malaccense
(Fig. 55) they were actually
confluent. As the central part
alone is confluent, an indenta-
tion is left at both the upper
and lower ends ; and the sur-
rounding colored 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 indenta-
tion at both ends, instead of at
the lower or basal cud alone.

The explanation, however, of
this difference is not difficult ;
in some species of Polyplec-
tron the two oval ocelli on the
same feather stand parallel to
each other; in other species
(as in P, chinguis) they con
verge tow ard one end ; now

the partial confluence of two

not have resembled

Fig. 54.— Part of a tail-covert of
Poly plcctron cbinquiB, with
the- two ocelli of natural size.

Pio. B5. —Pari <>r i i ..v.Ti <>r
Polyplectron moteoom^ Utth
the two ooolll, pArtUBj owl*

•Ot| <>f natural hIio.

134

. SEXUAL SELECTION : BIRDS.

[Pakt a

convergent ocelli would manifestly leave a much deeper
indentation at the divergent than at the convergent end.
It is also manifest that, if the convergence were strongly
pronounced and the confluence complete, the indentation
at the convergent end would tend to be quite obliterated.

The tail-feathers in both species of peacock are entire-
ly destitute of ocelli, and this apparently is related to
their being covered up and concealed by the long tail-cov-
erts. In this respect they differ remarkably from the
tail-feathers of Polyplectron, which in most of the species
are ornamented with larger ocelli than those on the tail-
coverts. Hence I was led carefully to examine the tail-
feathers of the several species of Polyplectron, in order to
discover whether the ocelli in any of them showed any
tendency to disappear, and, to my great satisfaction, I was
successful. The central tail-feathers of P. Napoleonis
have the two ocelli on each side of the shaft perfectly de-
veloped ; but the inner ocellus becomes less and less con-
spicuous on the more exterior tail-feathers, until a mere
shadow or rudimentary vestige is left on the inner side of
the outermost feather. Again, in JP. malaccense, the
ocelli on the tail-coverts are, as we have seen, confluent ;
and these feathers are of unusual length, being two-thirds
of the length of the tail-feathers, so that in both these
respects they resemble the tail-coverts of the peacock.
Now in this species the two central tail-feathers alone are
ornamented, each with two brightly-colored ocelli, the
ocelli having completely disappeared from the inner sides
of all the other tail-feathers. Consequently the tail-cov-
erts and tail-feathers of this species of Polyplectron make
a near approach in structure and ornamentation to the
corresponding feathers of the peacock.

As far, then, as the principle of gradation throws light
on the steps by which the magnificent train of the pea-
cock has been acquired, hardly any thing more is needed.

Chap. XIV.] GRADATION OF CHARACTER^

135

We may picture to ourselves a progenitor of the peacock
in an almost exactly intermediate condition between the
existing peacock, with his enormously elongated tail-cov-
erts, ornamented with single ocelli, and an ordinary gal-
linaceous bird with short tail-coverts, merely spotted with
some color; and we shall then see in our mind's eye a
bird possessing tail-coverts, capable of erection and ex-
pansion, ornamented with two partially confluent ocelli,
and long enough almost to conceal the tail-feathers — the
latter having already partially lost their ocelli ; we shall
see, in short, a Polyplectron. The indentation of the cen-
tral disk and surrounding zones of the ocellus in both spe-
cies of peacock, seems to me to speak plainly in favor of
this view ; and this structure is otherwise inexplicable.
The males of Polyplectron are no doubt very beautiful
birds, but their beauty, when viewed from a little dis-
tance, cannot be compared, as I formerly saw in the Zoo-
logical Gardens, with that of the peacock. Many female
progenitors of the peacock must, during a long line of de-
scent, 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 Pheasant. — Another excellent case for investi-
gation is offered by the ocelli on the wing-feathers of the
Argus pheasant, which are shaded in so wonderful a man-
ner as to resemble balls lying within sockets, and which
consequently differ from ordinary ocelli. No one, 1 pre-
sume, will attribute the shading, which h:is excited the ad-
miration of many experienced artists, to chance t<> the
fortuitous concourse of atoms of coloring 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

136

SEXUAL SELECTION: BIRDS.

[Part IL

effect, stems as incredible, as that one of Raphael's Ma-
donnas should have been formed by the selection of
chance daubs of paint made by a long succession of young
artists, not one of whom intended at first to draw the
human figure. In order to discover how the ocelli have
been developed, we cannot look to a long line of progeni-
tors, nor to various closely-allied forms, for such do nol
now exist. But fortunately the several feathers on the
wing suffice to give us a clew to the problem, and they
prove to demonstration that a gradation is at least pos-
sible from a mere spot to a finished ball-and-socket ocel-
lus.

The wing-feathers, bearing the ocelli, are covered with
dark stripes or rows of dark spots, each stripe or row run-
ning obliquely down the outer side of the shaft to an ocel-
lus, The spots are generally elongated in a transverse
line to the row in which they stand. They often be-
come confluent, either in the line of the row — and then
they form a longitudinal stripe — or transversely, that
is, with the spots in the adjoining rows, and then they
form transverse stripes. A spot sometimes breaks
up into smaller spots, which still stand in their proper
places.

It will be convenient first to describe a perfect ball-
and-socket ocellus. This consists of an intensely black
circular ring, surrounding a space shaded so as exactly to
resemble a ball. The figure here given has been admi-
rably drawn by Mr. Ford, and engraved, but a woodcut
cannot exhibit the exquisite shading of the original. The
ring is almost always slightly broken or interrupted (see
Fig. 56) at a point in the upper half, a little to the right
of and above the white shade on the enclosed ball ; it is
also sometimes broken toward the base on the right hand.
These little breaks have an important meaning. The ring
is always much thickened, with the edges ill-defined

Chap. XIV.] GRADATION OF CHARACTER.

137

toward the left-hand upper corner, the feather being held
erect, in the position a b c

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 downward
into a pale-leaden hue,
and this into yellow-
ish and brown tints,
which insensibly be-
come darker and dark-
er toward 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 browner

tint nnd U ind iv;i Inetl v Fia- 56.— Part of Secondary wing-feather of
tint anci is indistinctly ArffUg pheaBant showing twoTa and ©, per-

«or»intofl hv a mirvod ,r('1 ocelli. A. B, 0, etc., 'lark BtrlpeB run-

scparatea ny a curved ning oblIquely (1()WI1_ ,,„.,, „, M oeStta:

oblique line from the [Much of the webon both sides, especially to
^ 1. , . the left of the shaft, has been cut off].

upper part, winch is

yellower and more leaden; this oblique line runs at right
angles to t Tie longer iixis of the white patch of Light, and
indeed of :ill the shading; but this diflcrcncc in the tints,
which cannot of course be shown in the woodcut, docs not
in the least interfere with the perfect shading of the ball.4'

*H When the Argus pheasant displays bis wing-feathers Ukeiffraal
fan, those nearest to the body stand more upright than the outer ones,

138

SEXUAL SELECTION: BIRDS.

[Part II.

It should be particularly observed that each ocellus stands
in obvious connection with a dark stripe, or row of dark
spots, for both occur indifferently on the same feather.
Thus in Fig. 50 stripe A run&to ocellus a; B runs to ocellus
b ; stripe C is broken in the upper part and runs down to
the next succeeding ocellus, not represented in the wood-
cut ; D to the next lower one, and so with the stripes E and

F. Lastly, the several ocelli
are separated from each oth-
er by a pale surface bearing
irregular black marks.

I will next describe
the other extreme of the
series, namely, the first
trace of an ocellus. The
short secondary wing-
feather (Fig. 57), nearest
to the body, is marked,
like the other feathers,
with oblique, longitudi-
nal, rather irregular, rows
of spots. The lowest spot,
or that nearest the shaft,
in the five lower rows (ex-
cluding the basal row) is
a little larger than the

Fig. 57.-Baeal part of the Secondary tj t j tj gamc

wins-feather, nearest to the hody. UU1U o^mw

so that the shading of the ball-and-socket ocelli ought to be slightly
different on the different feathers, in order to bring out their full effect,
relatively to the incidence of the light. Mr. T. W. Wood, who has the
experienced eye of an artist, asserts ('Field,' newspaper, May 28, 1870,
p. 457) that this is the case; but after carefully examining two mounted
specimens (the proper feathers from one having been given to me by Mr.
Gould for more accurate comparison) I cannot perceive that this acme
of perfection in the shading has been attained; nor can others to whom
I have shown these feathers recognize the fact.

Chap. XIV.] GRADATION OF CHARACTERS.

139

row, and a little more elongated in a transverse direction.
It differs also from the other spots by being bordered on
its upper side with some dull fulvous shading. But this
spot is not in any way more remarkable than those on the
plumage of many birds, and might easily be quite over-
looked. The next higher spot in each row does not differ
at all from the upper ones in the same row, although in
the following series it becomes, as we shall see, greatly
modified. The larger spots occupy exactly the same rela-
tive position on this feather as those occupied by the per-
fect ocelli on the longer wing-feathers.

By looking to the next two or three succeeding sec-
ondary wing-feathers, an absolutely insensible gradation
can be traced from one of the above-described lower
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 shown in the accompany-
ing figure (Fig. 58). We here see several oblique rows,
A, B, C, D (see the lettered diagram), etc., of dark spots
of the usual character. Each row of spots runs down to
and is connected with one of the elliptic ornaments, in ex-
actly the same manner as eacli stripe in Fig. 56 runs down
to, and is connected with, one of the ball-and-socket ocelli.
Looking to any one row, for instance, B, the low est spot
or mark (b) is thicker and considerably longer than the
upper spots, and lias its left extremity pointed and curved
upward. This black mark is abruptly bordered on its
upper side by a rather broad space of richly-shaded tints,
beginning with a narrow brown zone, which passes into
orange, and this into a pale leaden tint, with the end
toward the shaft much paler. This mark corresponds in
every respect with the larger, shaded spot, described in
the last paragraph (Fig 57), but is more highly developed
and more brightly colored. To the right and above this

SEXUAL SELECTION : BIRDS. [Part II.

spot (ft), with its bright shading, there is a long, narrow,
black mark (c), belonging to the same row, and which is
arched a little downward so as to face (b). 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

Fig. 58. — Portion of one of the Secondary wing-feathers near to the hody ; phow

ing the so-called elliptic ornaments. The right-hand figure is given merely

as a diagram for the sake of the letters of reference.
A, B, C, etc. Rows of spots running c. The next succeeding spot or mark

down to and forming the elliptic in the same row.

ornaments. d. Apparently a hrokcn prolongation

b. Lowest spot or mark in row B. of the spot c in the same row B.

always more or less distinct from it, there is another black
mark (fl). This mark is generally sub-triangular and ir-
regular in shape, but in the one lettered in the diagram is
unusually narrow, elongated, and regular. It apparently
consists of a lateral and broken prolongation of the mark
(c), as I infer from traces of similar prolongations from
the succeeding upper spots ; but I do not feel sure of this.

Chap. XIV.] GRADATION OF CHARACTERS.

141

These three marks, b, c, and d, with the intervening bright
shades, form together the so-called elliptic ornament.
These ornaments stand in a line parallel to the shaft, and
manifestly correspond in position with the ball-and-socket
ocelli. Their extremely elegant appearance cannot be ap-
preciated in the drawing, as the orange and leaden tints,
contrasting so well with the black marks, cannot be
shown.

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. I regret that I have not given an additional
drawing, besides Fig. 58, which stands about half-way in
the series between one of the simple spots and a perfect
ocellus. The passage from the elliptic ornament into an
ocellus is effected by the elongation and greater curvature
in opposed directions of the lower black mark (&), and
more especially of the upper one (c), together with the
contraction of the irregular sub-triangular or narrow mark
(d), so that at last these three marks become confluent,
forming an irregular elliptic ring. This ring is gradually
rendered more and more circular and regular, at the same
time increasing in diameter. Traces of the junction of all
three elongated spots or marks, especially of the two upper
ones, can still be observed in many of the most perfect
ocelli. The broken state of the black ring on the upper
side of the ocellus in Fig. 5G was pointed out. The ir-
regular sub-triangular or narrow mark (</) manifestly
forms, by its contraction and equalization, tlic thickened
portion of the ring on the left upper side of the perfect
ball-and-socket ocellus. The lower part of the ring is in-
variably a little thicker than the other parts (see Kig. "><>),
and this follows from the lower black mark of the elliptic

ornament (A) having been originally thioker than the
upper mark (c). Every step can be followed Ln the pro*

142

SEXUAL SELECTION: BIRDS.

[Part II.

cess of confluence and modification; and the black ring
which surrounds the ball of the ocellus is unquestionably
formed by the union and modification of the three black
marks, b, c, <7, of the. elliptic ornament. The irregular
zigzag black marks between the successive ocelli (see
again Fig. 50) are plainly due to the breaking up of the
somewhat more regular but similar marks between the
elliptic ornaments.

The successive steps in the shading of the ball-and-
socket ocelli can be followed out with equal clearness.
The brown, orange, and pale-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 toward
the left-hand corner rendered still lighter, so as to become
almost white. But even in the most perfect ball-and-
socket ocelli a slight ditference in the tints, though not in
the shading, between the upper and lower parts of the
ball can be perceived (as was before especially noticed),
the line of separation being oblique, in the same direction
with the bright-colored shades of the elliptic ornaments.
Thus almost every minute detail in the shape and coloring
of the ball-and-socket ocelli can be shown to follow from
gradual changes in the elliptic ornaments; and the de-
velopment of the latter can be traced by equally small
steps from the union of two almost simple spots, the lower
one (Fig. 57) having some dull fulvous shading on the
upper side.

The extremities of the longer secondary leathers which
bear the perfect ball-and-socket ocelli are peculiarly orna-
mented. (Fig. 59.) The oblique longitudinal stripes
suddenly cease upward and become confused, and above
this limit the whole upper end of the feather (a) is covered
with white dots, surrounded by little black rings, stand-
ing on a dark ground. Even the oblique stripe belonging

Chap. XIV.] GRADATION OF CHARACTERS.

143

to the uppermost ocellus (b) is represented only by a very
short irregular black mark with the usual, curved, trans-
verse base. As this stripe is thus abruptly cut off above,
we can understand, from what has gone before, how it is
that the upper thickened part
of the ring is absent in the
uppermost ocellus ; for, as
before stated, this thickened
part is apparently formed
by a broken prolongation of
the next higher spot in the
same row. From the absence
of the upper and thickened
part of the ring, the upper-
most ocellus, though perfect
in all other respects, appears
as if its top had been ob-
liquely sliced off. It would, I
think, perplex any one, who
believes that the plumage of
the Argus pheasant was cre-
ated as we now see ir, to ac-
count for the imperfect condi-
tion of the uppermost ocelli.
T should add that in the sec-
ondary wing-feather farthest
from the body all the ocelli

are smaller and less perfect Fig. 69.— Portion near summit of one
. . . _ r . of the Secondary wlng-feattwrs,

than on the other feathers,

with the upper parts <>f the

external black rings deficient,

as in the case just mentioned.

The imperfection here seems
to be connected with the fact,
that the Spots on this feather

bearing DOrfeCl hall !iinl-M»i ki't

a. Ornament* i upper m rt

b. Uppermost, Imperfbrt hall snd«
■ockel ocellus, (The shading
above tin' white mark on tki

Hiimmil I In* oocIIuh Ih liriv ;»

inn, too dark.)
0, Perfect oc llus.

ihow less tendency than

144

SEXUAL SELECTION: BIRDS.

usual to become confluent into stripes; on the contrary,
they are often broken up into smaller spots, so that two
or three rows run down to each ocellus.

We have now seen that a perfect series can be
followed, from two almost simple spots, at first quite
distinct from each other, to one of 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 show us the
steps which have been passed through by the extinct pro-
genitors of the species ; but they probably give us the
clew to the actual steps, and they at least prove to demon-
Btration 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 ren-
dering it probable that female birds prefer the more at-
tractive males, no one who admits the agency of sexual
selection will deny that a simple dark spot with some
fulvous shading might be converted through the approxi-
mation and modification of the adjoining spots, together
with some slight increase of color, into one of the so-called
elliptic ornaments. These latter ornaments have been
shown to many persons, and all have admitted that they
are extremely pretty, some thinking them even more
beautiful than the ball-and-socket ocelli. As the second-
ary plumes became lengthened through sexual selection,
and as the elliptic ornaments increased in diameter, their
colors apparently became less bright ; and then the orna-
mentation of the plumes had to be gained by improve-
ments in the pattern and shading ; and this process has
been carried on until the wonderful ball-and-socket ocelli
have been finally developed. Thus we can understand —
and in no other way, as it seems to me — the present con-

Chap. XIV.] GRADATION OF CHARACTERS.

145

dition and origin of the ornaments on the wing-feathers
of the Argus pheasant.

From the light reflected 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 domesti-
cated birds ; and, lastly, from the character (as we shall
hereafter more clearly see) of the immature plumage of
young birds — we can sometimes indicate, with a certain
amount of confidence, the probable steps by which the
males have acquired their brilliant plumage and various
ornaments ; yet in many cases we are involved in dark-
ness. Mr. "Gould several years ago pointed out to me a
humming-bird, the TTrosticte benjamini, remarkable from
the curious differences presented by the two 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, while the female has the
six exterior feathers ornamented with white tips. What
makes the case curious is that, although the coloring of
the tail differs remarkably in both sexes of many kinds
of humming-birds, Mr. Gould does not know a single
species, besides the Urosticte, in which the male has the
four central feathers tipped with white.

The Duke of Argyll, in commenting on this case,4"
passes over sexual selection, and asks, " What explanation
does the law of natural selection give of such specific va-
rieties as these?" lie answers "none whatever;" and I
quite agree with him. But can this be so confidently
said of sexual selection? Seeing in how many ways the
tail-feathers of humming-birds differ, why should not the
four central feathers have varied in this one Bpeoies alone,

49 'The Kcign of La< 1807, p. Ul.
26

146

SEXUAL SELECTION: BIRDS. [Part II.

so as to have aqcuired white tips ? The variations may-
have been gradual, or somewhat abrupt as in the case re-
cently 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 Uros-
tictc I noticed extremely minute or rudimental white tips
to the two outer of the four central black tail-feathers ; so
that here we have an indication of change of some kind in
the plumage of this species. If we grant the possibility
of the central tail-feathers of the male varying in white-
ness, 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 in-
ferred from such cases as the snow-white male of the Bell-
bird. The statement made by Sir II. Ileron should not
be forgotten, namely, that his peahens, when debarred
from access to the pied peacock, would not unite with any
other male, and during that season produced no offspring.
Nor is it strange that variations in the tail-feathers of the
Urosticte should have been specially selected for the sake
of ornament, for the next succeeding genus in the family
takes its name of Metallura from the splendor of these
feathers. Mr. Gould, after describing the peculiar plu-
mage of the Urosticte, adds, " that ornament and variety
is the sole object, I have myself but little doubt." 60 If this
be admitted, we can perceive that the males which were
decked in the most elegant and novel manner would have
gained an advantage, not in the ordinary struggle for life,
but in rivalry with other males, and would consequently
have left a larger number of offspring to inherit their
newly-acquired beauty.

90 1 Introduction to the TrochilidV 1861, p. 110.

2hap. XV.] SEXUALLY-LIMITED INHERITANCE.

147

CHAPTER XV.

Birds — continued.

Discussion why the Males alone of some Species, and hoth Sexes of other
Species, are brightly colored. — On Sexually-limited Inheritance, as ap-
plied to Various Structures and to Brightly-colored Plumage. — Nidifi-
cation in Eelation to Color. — Loss of Nuptial Plumage during tho
Winter.

We have in this chapter to consider, why with many
kinds of birds the female has not received the same orna-
ments as the male; and why, with many others, both
sexes are equally, or almost equally, ornamented? In the
following chapter we shall consider why in some few rare
cases the female is more conspicuously colored than the
male.

In my 'Origin of Species'1 I briefly suggested that
the long tail of the peacock would be inconvenient, and
the conspicuous black color of the male capercailzie dan-
gerous, to the female during the period of incubation ; and
consequently that the transmission of these characters
from the male to the female offspring had been checked
through natural selection. I still think that this may
have occurred in some few instances : but after mature
reflection on all the facts which I have been able to collect}
I am now inclined to believe that when the sexes ditler,
the successive variations have generally been from the
first limited in their transmission to the same se.v in whieh

• Fourth edition, 1800, p. 1141.

148 SEXUAL SELECTION: BIRDS. [Part II.

they first appeared. Since my remarks appeared, the sub-
ject of sexual coloration has been discussed in some very
interesting papers by Mr. Wallace,3 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 colors of the male, owing to the danger which
she would thus have incurred during incubation.

This view necessitates a tedious discussion on a diffi-
cult point, namely, whether the transmission of a charac-
ter, which is at first inherited by both sexes, can be subse-
quently limited in its transmission, by means of selection,
to one sex alone. We must bear in mind, as shown in the
preliminary chapter on sexual selection, that characters
which are limited in their development to one sex are
always latent in the other. An imaginary illustration will
best aid us in seeing the difficulty of the case : we may
suppose that a fancier wished to make a breed of pigeons,
in which the males alone should be colored of a pale blue,
while the females retained their former slaty tint. As with
pigeons characters of all kinds are usually transmitted to
both sexes equally, the fancier would have to try to con-
vert this latter form of inheritance into sexually-limited
transmission. All that he could do would be to persevere
in selecting every male pigeon which was in the least
degree of a paler blue ; and the natural result of this pro-
cess, if steadily carried on for a long time, and if the pale
variations were strongly inherited or often recurred, would
be to make his whole stock of a lighter blue. But our
fancier would be compelled to match, generation after gen-
eration, his pale-blue males with slaty females, for he wishes
to keep the latter of this color. The result would generally
be the production either of a mongrel piebald lot, or

''Westminster Review,' July, 1867. 'Journal of Travel,' vol. L
1868, p. 13.

Chap. XV.] SEXUALLY-LIMITED INHERITANCE. 149

more probably the speedy and complete loss of the pale-
blue color, for the primordial slaty tint would be trans-
mitted with prepotent force. Supposing, however, that
some pale-blue males and slaty females were produced
during each successive generation, and were always crossed
together ; then the slaty females would have, if I may use
the expression, much blue blood in their veins, for their
fathers, grandfathers, etc., will all have been blue birds.
Under these circumstances it is conceivable (though I
know of no distinct facts rendering it probable) that the
slaty females might acquire so strong a latent tendency to
pale-blueness that they would not destroy this color in their
male offspring, their female offspring still inheriting the
slaty tint. If so, the desired end of making a breed with
the two sexes permanently different in color might be
gained.

The extreme importance, or rather necessity, of the de-
sired character in the above case, namely, pale-blueness,
being present though in a latent state in the female, so that
the male offspring should not be deteriorated, will be best
appreciated as follows : the male of Soemmerring's pheasant
has a tail thirty-seven inches in length, while that of the
female is only eight inches ; the tail of the male common
pheasant is about twenty inches and that of the female
twelve inches long. Now if the female Sccmmerring pheas-
ant with her short tail were crossed with the male com-
mon 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 her tail nearly
twice as long as that of the female Scemnicrring pheasant,
were crossed with the male of the latter, the male hybrid
offspring would have a much shorter tail than that of the
pure offspring of Scemmerring's pheasant.1

8 Tcmniinck says that the tail of tho IViuale I'loisimus Saimn<r>ii»jii

150

SEXUAL SELECTION: BIRDS.

[Part II.

Our fancier, in order to make his new breed with the
males of a decided pale-blue tint, and the females un-
changed, would have to continue selecting the males during
many generations ; and each stage of paleness would have
to be fixed in the males, and rendered latent in the fe-
males. The task would be an extremely difficult one, and
has never been tried, but might possibly succeed. The
chief obstacle would be the early and complete loss of the
pale-blue tint, from the necessity of reiterated crosses with
the slaty female, the latter not having at first any latent
tendency to produce pale-blue offspring.

On the other hand, if one or two males were to vary
ever so slightly in paleness, and the variations were from
the first limited in their transmission to the male sex, the
task of making a new breed of the desired kind would be
easy, for such males would simply have to be selected and
matched with ordinary females. An analogous case has
actually occurred, for there are breeds of the pigeon in
Belgium4 in which the males alone are marked with black
stria?. In the case of the fowl, variations of color limited
in their transmission to the male sex' habitually occur.
Even when this form of inheritance prevails, it might
well happen that some of the successive steps in the
process of variation might be transferred to the female,
who would then come to resemble in a slight degree the
male, as occurs in some breeds of the fowl. 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

is only six inches long, 'Planches colorizes,' vol v. 1838, pp. 478, 498:
the measurements above given vrere made for mc by Mr. Sclatcr. For
the common pheasant, see Macgillivray, 'Hist. British Birds,' vol. i. pp.
118-121.

4 Dr. Chapuis, 'Le Pigeon Yoyageur Beige,' 1865, p. 87.

Chap. XV.] SEXUALLY-LIMITED INHERITANCE.

151

somewhat larger crop, and of the male carrier-pigeon
having somewhat larger wattles, than their respective fe-
males ; 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 would be encountered, if it were desired
to make a breed with the females alone of some new
color.

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, un-
less the successive variations were from the first sexually
limited on both sides, and then there would be no diffi-
culty. We see this with the fowl ; thus the two sexes of
the pencilled Hamburgs differ greatly from each other,
and from the two sexes of the aboriginal Gallus banhiva y
and both are now kept constant to their standard of excel-
lence 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 succes-
sive variations, by the accumulation of which it was ac-
quired, appear to have been transferred to the female ; for
she has a comb many times larger than that of the females
of the parent-species. But the comb of the female differs in
one respect from that of the male, for it is apt to lop over ;
and within a recent period it has been ordered by the fancy
that this should always be the case, and success lias quickly
followed the order. Now, the lopping of the comb must
bo sexually limited in its transmission, otherwise it would
prevent the comb of the male from being perfectly upright,
which would be abhorrent to every fancier. On the other
hand the uprightness of the comb in the! male must likewise

152

SEXUAL SELECTION: BIRDS.

[Part II.

"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 ex-
tremely difficult and complex process, though perhaps not
impossible, to change through selection one form of trans-
mission into the other. Therefore, without distinct evi-
dence in each case, I am unwilling to admit that this has of-
ten been effected with natural species. On the other hand,
by means of successive variations, which were from the
first sexually limited in their transmission, there would not
be the least difficulty in rendering a male bird widely differ-
ent in color 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 colors are of service to the males in their
rivalry with other males, such colors would be selected,
whether or not they were transmitted exclusively to the
same sex. Consequently the females might be expected
often to partake of the brightness of the males to a greater
or less degree ; and this occurs with a host of species. If
all the successive variations were transmitted equally to
both sexes, the females would be undistinguishable from the
males ; and this likewise occurs with many birds. If, how-
ever, dull colors were of high importance for the safety of
the female during incubation, as with many ground birds,
the females which varied in brightness, or which received
through inheritance from the males any marked accession
of brightness, would sooner or later be destroyed. But the
tendency in the males to continue for an indefinite period
transmitting to their female offspring their own bright-
ness, would have to be eliminated by a change in the form
of inheritance; and this, as shown by our previous illus-
tration, would be extremely difficult. The more probable
result of the lohg'-continued destruction of the more bright-

Chap. XV.] SEXUALLY-LIMITED INHERITANCE.

153

ly-colored females, supposing the equal form of trans-
mission to prevail, would be the lessening or annihila-
tion of the bright colors of the males, owing to their
continually crossing with the duller females. It would
be tedious to follow out all the other possible results ; but
I may remind the reader, as shown in the eighth chapter,
that if sexually-limited variations in brightness occurred
in the females, even if they were not in the least injurious
to" them and consequently were not eliminated, yet they
would not be favored or selected, for the male usually
accepts any female, and does not select the more attrac-
tive individuals ; consequently these variations would be
liable to be lost, and would have little influence on the
character of the race ; and this will aid in accounting for
the females being commonly less brightly colored than
the males.

In the chapter just referred to, instances were given,
and any number might have been added, of variations
occurring at different ages, and inherited at the same
age. It was also shown that variations which occur late
in life are commonly transmitted to the same sex in
which they first appeared; while variations occurring
early in life are apt to be transmitted to both sexes ; not
that all the cases of sexually-limited transmission can thus
bo accounted for. It was further shown that if a male
bird varied by becoming brighter while young, such varia-
tions 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 which live on the ground
and which commonly need the protection of dull color?',
bright tints would be far more dangerous to the young
and inexperienced than to the adult males. < \»nsequently
the males which varied in brightness while young would
Buffer much destruction and he eliminated through nat-
ural selection ; on the other hand the males which varied

154

SEXUAL SELECTION: BIRDS. [Paut II.

in this manner when nearly mature, notwithstanding
that they were exposed to some additional danger,
might survive, and, from being favored through sexual
selection, would procreate their kind. The brightly-col-
ored young males being destroyed and the mature ones
being successful in their courtship may account, on the
principle of a relation existing between the period of
variation and the form of transmission, for the males
alone of many birds having acquired and transmitted
brilliant colors to their male offspring alone. But I by
no means wish to maintain that the influence of age
on the form of transmission is indirectly the sole cause
of the great difference in brilliancy between the sexes of
many birds.

As with all birds in which the sexes differ in color,
it is an interesting question whether the males alone
have been modified through sexual selection, the fe-
males being left, as far as this agency is concerned,
unchanged or only partially changed; or whether the
females have been specially modified through natural
selection for the sake of protection, I will discuss this
question at considerable length, even at greater length
than its intrinsic importance deserves ; for various cu-
rious collateral points may thus be conveniently consid-
ered.

Before we enter on the subject of color, more espe-
cially in reference to Mr. Wallace's conclusions, it may be
useful to discuss under a similar point of view some other
differences between the sexes. A breed of fowls formerly
existed in Germany6 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

6 Bechstein, 'Naturgesch. Deutscblandf*,' 1793, B. Hi. s. 339

Chap. XV.]

DEVELOPMENT OF SPURS.

155

it appeared to me probable that with, the females of the
wild Gallinaceae the development of spurs had been checked
through natural selection, from the injury thus caused to
their nests. This seemed all the more probable as the
wing-spurs, which could not be injurious during nidification,
are often as well developed in the female as in the male ;
though in not a few cases they are rather larger in the
male. When the male is furnished with leg-spurs the
female almost always exhibits rudiments of them — the
rudiments sometimes consisting of a mere scale, as with the
species of Gallus. Hence it might be argued that the fe-
males had aboriginally been furnished with well-developed
spurs, but that these had subsequently been lost either
through disuse or natural selection. But if this view be
admitted, it would have to be extended to innumerable
other cases ; and it implies that the female progenitors of
the existing spur-bearing species were once encumbered
with an injurious appendage.

In some few genera and species, as in Galloperdix,
Acomus, and the Javah peacock (Pav o muticus), the fe-
males as well as the males possess well-developed spurs.
Are we to infer from this fact that they construct a differ-
ent sort of nest, not liable to be injured by their spurs,
from that made by their nearest allies, so that there has
been no need for the removal of their spurs ? Or arc we
to suppose that these females 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 oonolude that some
few of the successive variations, through which they were
developed in the males, occurred very early in life, and
were as a consequence transferred to the females, fa the
other and much rarer eases, in which t he females possess

156

SEXUAL SELECTION: BIRDS.

[Part II.

fully-developed spurs, we may conclude that all the succes-
sive variations were transferred to them; and that they
gradually acquired the inherited habit of not disturbing
their nests.

The vocal organs and the variously-modified feathers
for producing sound, as well as the proper instincts for
using them, often differ in the two sexes, but are sometimes
the same in both. Can such differences be accounted for
by the males having acquired these organs and instincts}
while 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.8 It is a safer
conclusion that as vocal and instrumental organs are of spe-
cial service only to the males during their courtship, these
organs were developed through sexual selection and con-
tinued use in this sex alone — the successive variations and
the effects of use having been from the first limited in their
transmission in a greater or less degree to the male off-
spring.

Many analogous cases could be advanced ; for instance,
the plumes on the head, which are 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 sometimes occurring in the same group of birds. It
would be difficult to account for a difference of this kind
between the sexes on the principle of the female having
been benefited by possessing a slightly shorter crest than

6 Daincs Barrington, however, thought it probable (' Phil. Transact.'
1*773, p. 164) that few female birds siDg, because the talent would have
been dangerous to them during incubation. He adds, that a similar
view may possibly account for the inferiority of the female to the male
in plumage.

Chap. XV.]

LENGTH OF TAIL IN FEMALE.

157

the male, and its consequent diminution or complete sup-
pression through natural selection. But 1 will take a
more favorable case, namely, the length of the tail. The
long train of the peacock would have been not only incon-
venient but dangerous to the peahen during the period of
incubation and while accompanying her young. Hence
there is not the least a priori improbability in the develop-
ment of her tail having been checked through natural
selection. But the females of various pheasants, which
apparently are exposed on their open nests to as much
danger as the peahen, have tails of considerable length.
The females as well as the males of the Menura superba
have long tails, and they build a domed nest which is a
great anomaly in so large a bird. Naturalists have won-
dered how the female Menura could manage her tail during
incubation ; but it is now known 7 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 toler-
able guide to the length of time the bird has been sit-
ting." Both sexes of an Australian kingfisher ( Tanysiptera
sylvia) have the middle tail-feathers greatly lengthened ;
and, as the female makes her nest in a hole, these feathers
become, as I am informed by Mr. R. B. Sharpe, much
crumpled during nidification.

In these two 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 some-
what shorter than those of the male, it might b€ argued
that their full development had been prevented through
natural selection. Judging from these cases, if, with the
peahen, the development of the tail had been checked only
when it became inconveniently or dangerously long, she
would have acquired a much longer tail than she actually
1 Mr. Ramsay, in Proc. Zoolog. Soc' 1 808, p. BO.

158

SEXUAL SELECTION: BIRDS.

[Part II.

possesses ; for her tail is not nearly so long, relatively to
the size of her body, as that of many female pheasants,
nor longer than that of the female turkey. It must also
be borne in mind that, in accordance with this view, as
soon as the tail of the peahen became dangerously long,
and its development was consequently checked, she would
have continually reacted on her male progeny, and thus
have prevented the peacock from acquiring his present
magnificent train. We may therefore infer that the length
of the tail in the peacock and its shortness in the peahen
are the result of the requisite variations in the maTe 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 pheas-
ants. In the Eared pheasant ( Crossoptilon auritum) the
tail is of equal length in both sexes, namely, sixteen or
seventeen inches; in the common pheasant it is about
twenty inches long in the male, and twelve in the female ;
in Scemmerring's pheasant, thirty-seven inches in the male,
and only eight in the female ; and lastly in Reeve's pheas-
ant it is sometimes actually seventy-two inches long in the
male and sixteen in the female. Thus in the several spe-
cies, the tail of the female differs much in length, irrespec-
tively 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, owing to the length of tail having
been injurious in a greater or less degree to the females of
the several species.

"We may now consider Mr. "Wallace's arguments in re-
gard to the sexual coloration of birds. He believes that

Chap. XV.] COLOR AND NIDIFICATION.

159

the bright tints, originally acquired through sexual selec-
tion by the males, would in all or almost all cases have
been transmitted to the females, unless the transference
had been checked through natural selection. I may here
remind the reader that various facts bearing on 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,8 that when both sexes
are colored in a strikingly-conspicuous manner the nest is
of such a nature as to conceal the sitting bird ; but when
there is a marked contrast of color between the sexes, the
male being gay and the female dull colored, the nest is
open and exposes the sitting bird to view. This coinci-
dence, as far as it goes, certainly supports the belief that
the females which sit on open nests have been specially
modified for the sake of protection. Mr. Wallace admits
that there are, as might have been expected, some excep-
tions to his two rules, but it is a question whether the
exceptions are not so numerous as seriously to invalidate
them.

There is in the first place much truth in the Duke of
Argyll's remark,9 that a large-domed nest is more con-
spicuous to an enemy, especially to all tree-haunting car-
nivorous animals, than a smaller open nest. Nor must
we forget that with many birds which build open nests
the males sit on the eggs and aid in feeding the young as
well as the females: this is the case, for instance, with
Pyranga cestiva™ one of the most splendid birds in the
United States, the male being vermilion, and the female
light brownish-green. Now, if brilliant colors hail been
extremely dangerous to birds while sitting on their open

8 1 Journal of Travel,' edited by A Mumiy, vol. i. lsc»s, p. 7s.
• Ibid, i>. 281.

•° Audubon, 'Ornithological biography,' vol. i. p.

160

SEXUAL SELECTION: BIRDS.

[Part II.

nests, the males in these cases would have suffered greatly.
It might, however, be of^such paramount importance to
the male to be brilliantly colored, in order to beat his
rivals, that this would more than compensate for some ad-
ditional danger.

Mr. Wallace admits that with the King-crows (Dicru-
rus), Orioles, and Pittidae, the females are conspicuously
colored, yet they 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 ; 11 and that with the birds of the
third group the females are brightly colored chiefly on
the under surface. Besides these cases the whole great
family of pigeons, which are sometimes brightly and
almost always conspicuously colored, and which are noto-
riously liable to the attacks .of birds of prey, offers a seri-
ous exception to the rule, for pigeons 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 bril-
liant than the males, are very brightly colored. Nor can
it be maintained that all female humming-birds, which are
brightly colored, escape detection by their tints being
green, for some display on their upper surfaces red, blue,
and other colors."

11 Jerdon, 'Birds of India,' vol. ii. p. 108. Gould's 'Hand-book of
the Birds of Australia,' vol. i. p. 463.

w For instance, the female Eupetomena macroura has the head and
tail dark blue with reddish loins ; the female Lampomis porphyrurus is
blackish-green on the upper surface, with the lores and sides of the
throat crimson ; the female Eulampis jugular ii has the top of the head
and back green, but the loins and the tail are crimson. Many other in-
stances of highly-conspicuous females could be given. See Mr. Gould's
magnificent work on this family.

Chap. XV.] COLOR AND NIDIFICATION. 161

In regard to birds which build in holes or construct
domed nests, other advantages, as Mr. Wallace remarks,
besides concealment are gained, such as shelter from the
rain, greater warmth, and in hot countries protection from
the rays of the sun ; 18 so that it is no valid objection
to his view that many birds having both sexes obscurely
colored build concealed nests.14 The female Horn-bills
(Buceros), for instance, of India and Africa are protected,
during nidification, with extraordinary care, for the male
plasters up the hole in which the female sits on her eggs,
and leaves only a small orifice through which he feeds
her ; she is thus kept a close prisoner during the whole
period of incubation ; 15 yet female hornbills are not more
conspicuously colored 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 colored and the fe-
males obscure, and yet the latter hatch their eggs in
domed nests. This is the case with the Grallinse of Aus-
tralia, the Superb Warblers (Maluridae) of the same coun-
try, the Sun-birds (Nectariniae), and with several of the
Australian Honey-suckers or Meliphagidse."

If we look to the birds of England we shall see that
there is no close and general relation between the colors
of the female and the nature of the nest constructed by

13 Mr. Salvin noticed in Guatemala (' Ibis,' 1864, p. 375) that hum-
ming-birds were much more unwilling to leave their nests during very
hot weather, when the sun was shining brightly, than during cool,
cloudy, or rainy weather.

14 I may specify, as instances of obscurely- colored birds building
concealed nests, the species belonging to eight Australian genera, de-
scribed in Gould's 'Hand-book of the Birds of Australia,' vol. i. pp. 310,
362, 365, 383, 387, 389, 391, 414.

16 Jerdon, 'Birds of India,' vol. i. p. 244.

16 On the nidification and colors of these latter Bpeoief, see Gould's
1 Hand-book,' etc., vol. i. pp. 504, 521

162

SEXUAL SELECTION: BIRDS. [Pabt II.

Lcr. About forty of our British birds (excluding those of
large size which could defend themselves) build in holes
iu banks, rocks, or trees, or construct domecl nests. If
we take the colors of the female goldfinch, bullfinch, or
blackbird, as a standard of the degree of conspicuousness,
which is not highly dangerous to the sitting female, then,
out of the above forty birds, the females of only twelve
can be considered as conspicuous to a dangerous degree,
the remaining twenty-eight being inconspicuous." Nor
is there any close relation between a well-pronounced dif-
ference in color between the two sexes and the nature of
the nest constructed. Thus the male house-sparrow
(Passer domesticus) differs much from the female, the
male tree-sparrow ( P. montanus) differs hardly at all, and
yet both build well-concealed nests. The two sexes of the
common fly-catcher (Muscicapa grisold) can hardly be
distinguished, while the sexes of the pied fly-catcher
(M. luctuosa) differ considerably, and both build in holes.
The female blackbird (Turdus morula) differs much, the
female ring-ouzel (T. torquatus) differs less, and the female
common thrush (T. musicus) hardly at all, from their re-
spective males ; yet all build open nests. On the other
hand, the not very distantly-allied water-ouzel ( Ciiiclus

17 I have consulted, on this subject, Macgillivray's 1 British Birds,'
and though doubts may be entertained in some cases in regard to the
degree of concealment of the nest, and of the degree of conspicuousness
of the female, yet the following birds, which all lay their eggs in holes or
in domed nests, can hardly be considered, according to the above stand-
ard, as conspicuous : Passer, 2 species ; Sturniis, of which the female is
considerably less brilliant than the male ; Cincjus ; Motacilla boarula (?) ;
Erithacus (?) ; Fruticola, 2 sp. ; Saxicola ; Ruticilla, 2 sp. ; Sylvia, 8 sp. ;
Parus, 3 sp. ; Mccistura ; Anorihura ; Ccrthia ; Sitta ; Yuni ; Muscicapa,
2 sp. ; Hirundo, 3 sp. ; and Cypselus. The females of the following 12
birds may be considered as conspicuous according to the same standard,
viz., Pastor, Motacilla alba, Parus major and P. caerulcus, Upupa, Picus,
4 sp., Coracias, Alccdo, and Mcrope.

Chap. XV.]

COLOR AND NIDIFICATION.

103

aguaticus) builds a domed nest, and the sexes differ about
as much as in the case of the ring-ouzel. The black and
red grouse (Tetrao tetrix and T. Scoticus) build open
nests, in equally well-concealed spots, but in the one spe-
cies 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 colored
(and in this case the males with rare exceptions are equal-
ly conspicuous) build concealed nests for the sake of pro-
tection. Mr. Wallace enumerates 18 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 (Capitonidse), plantain-eaters
(Musophagae), woodpeckers, and. parrots. Mr. Wallace
believes that in these groups, as the males gradually ac-
quired through sexual selection their brilliant colors, these
were transferred to the females and were not eliminated
by natural selection, owing to the protection which they
already enjoyed from their manner of nidification. Ac-
cording to this view, their present manner of nesting was
acquired before their present colors. But it seems to me
much more probable that, in most cases, as the females
were gradually rendered more and more brilliant from
partaking of the colors of the male, they were gradually
led to change their instincts (supposing that they origi-
nally built open nests), and to seek protection by building
domed or concealed nests. No one, who studies, for in-
stance, Audubon's account of tin; differences in the nests
of the same species in the Northern and Southern United
States," will feel any great difficulty in admitting thai
birds, either by a change (in the Btriot BGnso ofthe word)

18 •Journal of Travel,' edited by A. Murray, vol L p. 7H.

" Sec many itatantnti in tht 1 Ornlthologtoa] Biography.' Soo, jdao,

104

SEXUAL SELECTION: BIRDS.

[Part II.

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 colors of female birds and their
manner of nesting, receives some support from certain
analogous cases occurring in the Sahara Desert. Here, as
in most other deserts, various birds, and many other ani-
mals, have had their colors adapted in a wonderful man-
ner 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 col-
or, and the female almost equally conspicuous from her
mottled brown and white plumage; both sexes of two
species of Dromolcea are of a lustrous black; so that these
three birds are far from receiving protection from their
colors, yet they are able to survive, for they have acquired
the habit, when in danger, of taking refuge in holes or
crevices in the rocks.

With respect to the above-specified groups of birds,
in which the females are conspicuously colored and build
concealed nests, it is not necessary to suppose that each
separate species had its nidifying instinct specially modi-
fied ; but only that the early progenitors of each group
were gradually led to build domed or concealed nests ;
and afterward transmitted this instinct, together with
their bright colors, to their modified descendants. This
conclusion, as far as it can be trusted, is interesting,
namely, that sexual selection, together with equal or
nearly equal inheritance by both 6excs, has indirectly
determined the manner of nidification of whole groups of
birds.

some curious observations on the nests of Italian Birds by Engenio Bet-
toni, in the 4Atti dclla Socicta Italiana,' vol xl 1869, p. 487.

Chap. XV.]

COLOR AND NIDIFICATION.

165

Even in the groups in which, according to Mr. Wal-
lace, the females, from being protected during nidification,
have not had their bright colors eliminated through natu-
ral selection, the males often differ in a slight, and occa-
sionally in a considerable degree, from the females. This
is a significant fact, for such differences in color must be
accounted for on the principle of some of the variations
in the males having been from the first limited in their
transmission to the same sex ; as it can hardiy be main-
tained that these differences, especially when very slight,
serve as a protection to the female. Thus all the species
in the splendid group of the Trogons build in holes ; and
Mr. Gould givesfigures 20 of both sexes of twenty-five spe-
cies, in all of which, with one partial exception, the sexes
differ sometimes slightly, sometimes conspicuously in col-
or— the males being always more beautiful than the
females, though the latter are likewise beautiful. All the
species of kingfisher 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 colors of the females are rather less vivid than
those of the male ; and, in one splendidly-colored species,
the sexes differ so much that they were at first thought to
be specifically distinct.21 Mr. R. B. Sharpe, who has es-
pecially studied this group, has shown 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 part-
ly fawn-colored, and there is much red about the head ; to
the female the upper surface is reddish-brown banded
with black, and the lower surface white with Mack

10 See liin 'Monograph of tli<« Tropmida',' fust edition.
,l Namely ('yaiialcyon. Gould*! 'Hand-book of the Hiids of Austra-
lia,' vol. i. p. 188; hoc, fclfO, pp. 130, 136.

1GG

SEXUAL SELECTION: BIRDS.

[Part II.

markings. It is an interesting fact, as showing how the
same peculiar style of sexual coloring often characterizes
allied forms, that in three species of Dacelo the male dif-
fers from the female only in the tail being dull-blue
banded with black, while that of the female is brown with
blackish bars ; so that here the tail differs in color in the
two sexes in exactly the same manner as the whole upper
surface in the sexes of Carcineutes.

With parrots, which likewise build in holes, we find
analogous cases : in most of the species both sexes are
brilliantly colored and undistinguishable, but in not a few
species the males are colored rather more vividly than the
females, or even very differently from them. Thus, be-
sides other strongly-marked differences, the whole under
surface of the male King Lory (Aprosmictus scapulatus), is
scarlet, while the throat and chest of the female are green
tinged with red: in the Euphema splendida there is a
similar difference, the face and wing-coverts, moreover, of
the female being of a paler blue than in the male.98 In
the family of the Tits (Parinai), which build concealed
nests, the female of our common blue tomtit (Parus cceru-
leus) is " much less brightly colored " than the male ; and
in the magnificent Sultan yellow tit of India the differ-
ence is greater."

Again, in the great group of the woodpeckers,94 the
sexes are generally nearly alike, but in the Megapicus
validus all those parts of the head, neck, and breast,
which are crimson in the male are pale brown in the fe-

n Every gradation of difference between the sexes may be followed in
the parrots of Australia. See Gould's 'Hand-book,' etc., vol. ii. pp. 14-
102.

M Macgillivray's ' British Birds,' vol. ii. p. 433. Jerdon, 1 Birds of
India,' vol ii. p. 282.

u All the following facts are taken from M. Malherbc's magnificent
'Monographic des PicidSes,' 1861

Chap. XV.] COLOR AND NIDIFICATION.

167

male. As in several woodpeckers the head of the male is
bright crimson, while that of the female is plain, it oc-
curred to me that this color might possibly make the
female dangerously conspicuous, whenever she put her
head out of the hole containing her nest, and consequent-
ly that this color, in accordance with Mr. Wallace's belief,
had been eliminated. This view is strengthened by what
Malherbe states with respect to Indopicus carlotta;
namely, that the young females, like the young males,
have some crimson about their heads, but that this color
disappears in the adult female, while it is intensified in
the adult male. Nevertheless, the following considera-
tions render this view extremely doubtful : the male takes
a fair share in incubation,26 and would be thus far 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 appre-
ciable difference in the danger incurred ; and, lastly, the
coloring of the head in the two sexes often differs slightly
in other ways.

The cases, as yet given, of slight and graduated differ-
ences in color between the males and females in the
groups, in which as a general rule the sexes resemble each
other, all relate to species which build domed or concealed
nests. But similar gradations may likewise be observed
in groups in which the sexes as a general rule resemble
each other, but which build open nests. As I have before
instanced the Australian parrots, so I may here instance,
without giving any details, the Australian pigeons." It
deserves especial notice that in all these cases the slight
differences in plumage between the sexes are of the same

35 Audubon's ' Ornithological Ilio^rnphy,' vol. ii. p. V'» ; sco :ils<> the
1 Ibifl,' vol. i. p. iiCH.

88 Gould's 'Hand-book of the Birds of Australia,' roL ii. pp. 100-149,

168

SEXUAL SELECTION: BIRDS.

[Part II.

general nature as the occasionally greater differences. A
good illustration of this fact has already been afforded by
those kingfishers in which either the tail alone or the
whole upper surface of the plumage differs in the same
manner in the two sexes. Similar cases may be observed
with parrots and pigeons. The differences in color be-
tareen the sexes of the same species are, also, of the same
general nature as the differences in color between the dis-
tinct species of the same group. For, when, in a group in
which the sexes are usually alike, the male differs consid-
erably from the female, he is not colored in a quite new
style. Hence we may infer that, within the same group,
the special colors of both sexes, when they are alike, and
the colors of the male, when he differs slightly or even
considerably from the female, have in most cases been
determined by the same general cause ; this being sexual
selection.

It is not probable, as has already been remarked, that
differences in color between the sexes, when very slight,
can be of service to the female as a protection. Assum-
ing, 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 under-
going change. Therefore, we can hardly admit that the
numerous females which differ very slightly in color from
their males are now all commencing to become obscure
for the sake of protection. Even if we consider somewhat
more marked sexual differences, is it probable, for in-
stance, 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 pro-
cess 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

Chap. XV.] COLOR AND NIDIFICATION.

169

the other hand, the differences in color between the sexes,
whether great or small, may to a large extent be ex-
plained 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 transmis-
sion to the females. That the degree of limitation should
differ in different species of the same group will not sur-
prise any one who has studied the laws of inheritance, for
they are so complex that they appear to us in our igno-
rance to be capricious in their action.27

As far as I can discover, there are very few groups
of birds, containing a considerable number of species, in
which all have both sexes brilliantly colored and alike ;
but this appears to be the case, as I hear from Mr. Sclater,
with the Musophagae or plantain-eaters. Nor do I be-
lieve that any large group exists in which the sexes of all
the species are widely dissimilar in color : Mr. Wallace
informs me that the chatterers of South America (Cotin-
gidce) offer one of the best instances ; but with some of
the species, in which the male lias a splendid red breast,
the female exhibits some red on her breast ; and the fe-
males of other species show traces of the green and other
colors of the males. Nevertheless, we have a near ap-
proach to close sexual similarity or dissimilarity through-
out several groups: and this, from what has just been
said of the fluctuating nature of inheritance, is a some-
what surprising circumstance. But that the same laws
should largely prevail with allied animals is not surpris-
ing. The domestic fowl has produced a great number of
breeds and sub-breeds, ami in these the sexrs generally
differ in plumage ; so that it has been not ice. 1 :is a re-
markable circumstance when in certain sub-breeds they
resemble each other. On the other hand, the domettic

81 See remark H to this ('fleet in my work on ' Yni iution mnler Domes-
tication/ vol. ii. ( Imp. xii.

L>7

170 SEXUAL SELECTION: BIRDS. [Part II.

pigeon has likewise produced a vast number of distinct
breeds aiuT sub-breeds, and in these, with rare exceptions,
the two sexes are identically alike. Therefore, if other
species of Gallus and Col umba were domesticated and va-
ried, it would not be rash to predict that the same general
rules of sexual similarity and dissimilarity, depending on
the form of transmission, would, in both cases, hold good.
Iu a similar manner the same form of transmission has
generally prevailed throughout the same natural groups,
although marked exceptions to this rule occur. Within
the same family, or even genus, the sexes may be identi-
cally alike or very different in color. Instances have
already been given relating to the same genus, as with
sparrows, fly-catchers, thrushes, and grouse. In the fam-
ily of pheasants the males and females of almost all the
species are wonderfully dissimilar, but are quite similar
in the eared pheasant or Crossoptilon auritum. In two
species of Chloehaga, a genus of geese, the males cannot
be distinguished from the females, except by size ; while in
two others the sexes are so unlike that they might easily
be mistaken for distinct species.38

The laws of inheritance can alone account for the fol-
lowing cases, in which the female, by acquiring at a late
period of life certain characters proper to the male, ulti-
mately comes to resemble him in a more or less complete
manner. Here protection can hardly have come into play.
Mr. Blyth informs me that the females of Oriolus melan-
ocephalus and of some allied species, when sufficiently
mature to breed, differ considerably in plumage from the
adult males; but after the second or third moults they
differ only in their beaks having a slight greenish tinge.
In the dwarf bitterns (Ardetta), according to the same
authority, " the male acquires his final livery at the first
moult, the female not before the third or fourth moult ; in

«• The 'Ibis,' vol vi. 1864, p. 123..

Chap. XV.] COLOR AND NIDIFICATION.

171

the mean while she presents an intermediate garb, which
is ultimately exchanged for the same livery as that of the
male." So, again, the female Falco peregrinus acquires
her blue plumage more slowly than the male. Mr. Swin-
hoe states that, with one of the Drongo shrikes {JDicrurus
macrocercus), the male, while 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 stria? and spots on the axillary feathers, and does
not completely assume the uniform black color of the
male for the first three years. The same excellent ob-
server 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 male at a much earlier age. The
female Bomby cilia Carolinensis 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 the male. The upper mandible
in the male of an Indian parrakeet (Palccornis Javauicua)
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.""

On Ardetta, TrunMliition of ('uv'km'm 1 Ki ^iic Animal,' l\\ Mr. llluh,
foot-note, p. I.V.». On tlm IVicpinc Falcon, Mr. lilslli, in Cliarlo ITOTth*!
•Mntf. of Nat. Mint.' vol. i. Is:i7, \k HOI. On Dirrnni 1 ll.is,' IMS, p.
44. On tin- IMutalm, ' Ibis,' vol. vi. 1 Nf, I, ]>. On tlu' Itoinlm illu,

172

SEXUAL SELECTION: BIRDS.

[Part IL

In these cases, the females follow a normal course of
development in ultimately becoming like the males ; and
such cases must not be confounded with those in which
diseased or old females assume masculine characters, or
with those in which perfectly fertile females, while young,
acquire, through variation or some unknown cause, the
characters of the male.30 But all these cases have so much
in common that they depend, according to the hypothesis
of pangenesis, on gemmules derived from each part of the
male being present, though latent, in the female; their
development following on some slight change in the elec-
tive affinities of her constituent tissues.

A few words must be added on changes of plumage in
relation to the season of the year. From reasons formerly
assigned there can be little doubt that the elegant plumes,
long pendant feathers, crests, etc., of egrets, herons, and
many other birds, which are developed and retained only
during the summer, serve exclusively for ornamental or
nuptial purposes, though common to both sexes. The fe-
male is thus rendered more conspicuous during the period
of incubation than during the winter ; but such birds as
herons and egrets would be able to defend themselves.
As, however, plumes would probably be inconvenient and
certainly of no use during the winter, it is possible that
the habit of moulting twice in the year may have been
gradually acquired through natural selection for the sake
of casting off inconvenient ornaments during the winter.

Audubon's 1 Ornitholog. Biography,' vol. i. p. 229. On the Paljeornis,
see, also, Jerdon, 'Birds of India,' vol. i. p. 263. On the wild-turkey,
Audubon, ibid. vol. i. p. 15 : I hear from Judge Caton that in Illinois the
female very rarely acquires a tuft.

30 Mr. Blyth has recorded (Translation of Cuvier's • Rcgne Animal,' p.
158) various instances with Lanius, Ruticilla, Linaria, and Anas. Audu-
bon has also recorded a similar case ('Ornith. Biog.' vol. v. p. 519) with
Tyranga cutiva.

Chap. XV.]

SUMMER PLUMAGE.

173

But this view cannot be extended to the many waders,
in which the summer and winter plumages differ very
little in color. With defenceless species, in which either
both sexes or the males alone become extremely conspicu-
ous during the breeding-season — or when the males ac-
quire at this season such long wing or tail feathers as to
impede their flight, as with Cosmetornis and Vidua — it
certainly at first appears highly probable that the second
moult has been gained for the special purpose of throwing
off these ornaments. We must, however, remember that
many birds,' such as Birds of Paradise, the Argus pheasant,
and peacock, do not cast their plumes during the winter ;
and it can hardly be maintained that there is something
in the constitution of these birds, at least of the Gallina-
cese, rendering a double moult impossible, for the ptarmi-
gan moults thrice in the year.31 Hence it must be con-
sidered as doubtful whether the many species which moult
their ornamental plumes, or lose their bright colors, during
the winter, have acquired this habit on account of the in-
convenience or danger which they would otherwise have
suffered.

I conclude, therefore, that the habit of moulting twice
in the year was in most or all cases first acquired for some
distinct purpose, perhaps for gaining a warmer winter cov-
ering; and that variations in the plumage occurring
during the summer were accumulated through sexual se-
lection, and transmitted to the offspring at the same season
of the year; such variations being inherited either by both
sexes or by the males alone, according to the form of in-
heritance Which prevailed. This appears more probable
than that these species in all cases originally tended to
retain their ornamental plumage during the winter, but
were saved from this through natural selection, owing to
the inconvenience or danger thus caused.

:" Sit Gcm.M'h ' ItirtlH of Great Itril tin.'

174: SEXUAL SELECTION: BIRDS. [Part II.

I have endeavored in this chapter to show that the
arguments are not trustworthy in favor of the view that
weapons, bright colors, and various ornaments, are now
confined to the males owing to the conversion, by means
of natural selection, of a tendency to the equal transmis-
sion of characters to both sexes into transmission to the
male sex alone. It is also doubtful whether the colors of
many female birds are due to the preservation, for the sake
of protection, of variations which were from the first limit-
ed in their transmission to the female sex. But it will be
convenient to defer any further discussion on- this subject
until I treat, in the following chapter, on the differences in
plumage between the young and old.

Chap. XVI.] INHERITANCE, LIMITED BY AGE.

175

CHAPTER XVI.

Birds— concluded.

The Immature Plumage in Relation to the Character of the Plumage in
both Sexes when Adult. — Six Classes of Cases. — Sexual Differences
between the Males of Closely-allied or Representative Species. — The
Female assuming the Characters of the Male. — Plumage of the Young
in Relation to the Summer and Winter Plumage of the Adults. — On
the Increase of Beauty in the Birds of the "World. — Protective Color-
ing.— Conspicuously-colored Birds. — Novelty appreciated. — Summary
of the Pour Chapters on Birds.

We must now consider the transmission of characters
as limited by age in reference to sexual selection. The
truth and importance of the principle of inheritance at
corresponding ages need not hero be discussed, as enough
has already been said on the subject. Before giving the
several rather complex rules or classes of cases, under
which all the differences in plumage between the young
and the old, as far as known to me, may be included, it
will be well to make a few preliminary remarks.

With animals of all kinds, when the young differ in
color from the adults, and the colors of the former are
not, as far as we can see, of any special Ben ice, they may
generally be attributed, like various emhryological struct-

ures, to the retention by the young of the character of an
early progenitor. lint this view can he maintained with
confidence only w hen the young of several species closely

resemble each oilier, ami likewise resemble other adult,
species belonging to the same group; for the Latter are

the living proofs that such a stale of things wu.s formerly

176

SEXUAL SELECTION: BIRDS.

[Taut II.

possible. Young lions and pumas arc marked with feeble
stripes or rows of spots, and, as many allied species both
young and old are similarly marked, no naturalist, who
believes in the gradual evolution of species, will doubt
that the progenitor of the lion and puma was a striped
animal, the young having retained vestiges of the stripes,
like the kittens of black cats, which when grown up are
not in the least striped. Many species of deer, which
Avhen mature are not spotted, are while young covered
with white spots, as arc likewise some few species in their
adult state. So, again, the young in the whole family
of pigs (Suida?), and in certain rather distantly-allied ani-
mals, 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
colors changed in the course of time, while the young
have remained but little altered, and this has been effect-
ed through the princijde of inheritance at corresponding
ages.

This same principle applies to many birds belonging
to various group*, in which the young closely resemble
each other, and differ much from their respective adult
parents. The young of almost all the Gallinacea?, and of
some distantly-allied birds such as ostriches, are, while
covered with down, longitudinally striped ; but this charac-
ter points back to a state of things so remote that it hard-
ly concerns us. Young cross-bills (Loxia) have at first
straight beaks like those of other finches, and in their im-
nuiture 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 each other,
and likewise the adult state of the common bunting, JK
miliaria. In almost the whole large group of thrushes

Chap. XVL] INHERITANCE, LIMITED BY AGE.

177

the young have their breasts spotted — a character which
is retained by many species throughout life, 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 charac-
ter is retained for life by certain Eastern species. The
young of many species of shrikes (Lanius), of some wood-
peckers, and of an Indian pigeon (Chalcophaps Indicus),
are transversely striped on the under surface ; and certain
allied species or genera when adult are similarly marked.
In some closely-allied and resplendent Indian cuckoos
(Chrysococcyx), the species when mature differ consider-
ably from each other in color, but the young cannot be
distinguished. The young of an Indian goose (Sarkidior-
nis melanonotus) closely resemble in plumage an allied
genus, Dendrocygna, when mature.1 Similar facts will
hereafter be given in regard to certain herons. Young
black grouse (Tetrao tetrix) resemble the young as well as
the old of certain other species, for instance, the red grouse
or T. Scoticus. Finally, as Mr. Blytli, who has attended
closely to this subject, has well remarked, the natural
affinities of many species are best exhibited in their im-
mature plumage ; and, as the true affinities of all organic
beings depend on their descent from a common progenitor,
this remark strongly confirms the belief that the immature
plumage approximately shows us the former or ancestral
condition of the species.

Although many young birds belonging to various or-

1 In regard to thrushes, shrikes, mid woodpeckers, see Mr. Myth, in
C'harlcHWorth's 'Mag. of Nat. Hist.' vol. i. 1 8:17, i>. -"I ; also loot-note to
fail translation of Cuvier'tj * Regno Animal,' p. 1M>. I give tin* ease of
Loxia from Mr. Myth's information. On thrushes, see, also, Awduhon,
1 Ornith. Biography? vol. ii. p. 195. On Chrysococcyx ami Chalcophnpa,
Myth, as quoted in Jerdon's ' Mrds of India,' vol. iii. p. I*r>. On Sur-
kidiornis, Myth, in 1 II. is,' 1867, p. 175.

178

SEXUAL SELECTION: BIRDS.

[Part II.

ders thus give us a glimpse of the plumage of their remote
progenitors, yet they are many other birds, both dull-
colored and bright-colored, in which the young closely re-
semble their parents. With such species the young of the
different species cannot resemble each other more closely
than do the parents ; nor can they present striking resem-
blances to allied forms in their adult state. They give us
but little insight into the plumage of their progenitors, ex-
cepting in so far that, when the young and the old are
colored in the same general manner throughout a whole
group of species, it is probable that their progenitors were
similarly colored.

We may now consider the classes of cases or rules
under which the differences and resemblances, between the
plumage of the young and the old, of both sexes or of one
sex alone, may be grouped. Rules of this kind were first
enounced by Cuvier ; but with the progress of knowledge
they require some modification and amplification. This I
have attempted to do, as far as the extreme complexity
of the subject permits, from information derived from
various sources ; but a full essay on this subject by some
competent ornithologist is much needed. In order to
ascertain to what extent each rule prevails, I have tabu-
lated the facts given in four great works, namely, Macgilli-
vray 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, firstly, that the several
cases or rules graduate into each other ; and, secondly,
that, when the young are said to resemble their parents, it
is not meant that they are identically alike, for their
colors are almost always rather less vivid, and the feathers
arc softer and often of a different shape.

Chap. XVI.] CLASSES OF CASES.

179

RULES OR CLASSES OF CASES.

I. When the adult male is more beautiful or conspicu-
ous 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 cacli other according to se\ ; the young males
resembling more or less closely the adult males, :md the
young females more or less closely the adull females,

('lass I. — Tn this class, the young of hoth sexes iv-
Bcmble, more or less closely, the adult female, while the

adult male differs, often in the most conspicuous manner,
from the adult female. Innumerable instant - in all Or-

180

SEXUAL SELECTION: BIRDS. [Part II.

ders could be given ; it will suffice to call to mind the
common pheasant, duck, and house-sparrow. The cases
under this class graduate into others. Thus the two sexes
when adult may differ so slightly, and the young so
slightly from the adults, that it is doubtful whether such
cases ought to come under the present, or under the third
or fourth classes. So, again, the young of both sexes, in-
stead of being quite alike, may differ in a slight degree
from each other, as in our sixth class. These transitional
cases, however, are few in number, 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 shown in those
groups, in which, as a general rule, the two sexes and the
young are all alike; for when the male in these groups
does differ from the female, as with certain parrots, king-
fishers, pigeons, etc., the young of both sexes resemble
the adult female.3 We see the same fact exhibited still
more clearly in certain anomalous cases ; thus the male
of Heliothrix auriculata (one of the humming-birds) differs
conspicuously from the female in having a splendid gorget
and fine ear-tufts, but the female is remarkable from having
a much longer tail than that of the male ; now, the young
of both sexes resemble (with the exception of the breast

* Sec, for instance, Mr. Gould's account (' Iland-book of the Birds of
Australia,' vol. i. p. 133) of Cyanalcyon (one of the Kingfishers), in which,
however, the young male, though resembling the adult female, is less
brilliantly colored. In some species of Dacelo the males have blue tails,
and the females brown ones ; and Mr. R. B. Sharpe informs me that the
tail of the young male of D. Gaudichaudi is at first brown. Mr. Gould
has described (ibid. vol. ii. pp. 14, 20, 37) the sexes and the young of
certain Black Cockatoos and of the King Lory, with which the same rule
prevails. Also Jcrdon (4 Birds of India,' vol. i. p. 260) on the Palceornis
rosa, in which the young arc more like the female than the male. See
Audubon ('Ornitb. Biograph.' vol. ii. p. 475) on the two sexes and the
young of Columba pamrina.

Chap. XVI] THE YOUNG LIKE THE ADULT FEMALES. 181

being spotted with bronze) the adult female in all respects,
including the length of her tail, so that the tail of the male
actually becomes shorter as he reaches maturity, which is
a most unusual circumstance.3 Again, the plumage of
the male goosander {Mergus merganser) is more conspicu-
ously colored, with the scapular and secondary wing-
feathers much longer than in the female, 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 resemble
in all respects the adult female, so that their crests are
actually of greater length, though narrower, than in the
adult male.4

When the young and the females closely resemble
each other and both differ from the male, the most obvious
conclusion is that the male alone has been modified. Even
in the anomalous cases of the Heliothrix and Mergus, it
is probable that originally both adult sexes were furnished,
the one species with a much elongated tail, and the other
with a much elongated crest, these characters having since
been partially lost by the adult males from some unex-
plained cause, and transmitted in their diminished state to
their male offspring alone, when arrived at the correspond-
ing age of maturity. The belief that in the present class
the male alone has been modified, as far as the differences
between the male and the female, together with her young,
are concerned, is strongly supported by some remarkable
facts recorded by Mr. Blyth,6with respect to closely-allied

8 I owe this information to Mr. Gould, who showed mo t lie specimens :
see also his 'Introduction to the Trochilida',' 1861, p. 120.
4 Macgillivruy, 'Hist. Brit Birds,1 vol. v. pp. 207-21 L
6 See his admirable paper in the ' Journal of the Asiatic Soc. of Hen-
gal,' vol. xix. 1850, p. 223; see also .Tcrdon, 'Birds of India,' vol. i. in-

182

SEXUAL SELECTION: BIRDS.

[Part EL

species which represent each other in distinct countries.
For with several. of these representative species the adult
males have undergone a certain amount of«change and can
be distinguished ; the females and the young being undis-
tinguishable, and therefore absolutely unchanged. This
is the case with certain Indian chats (Thamnobia), with
certain honeysuckers (Nectarinia), shrikes (Tephrodornis),
certain kingfishers (Tanysiptera), Kallij pheasants (Gal-
lophasis), and tree-partridges (Arboricola).

In some analogous cases, namely, with birds having
a distinct 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 undistinguishable in their winter as well as in their
immature plumage. This is the case with some of the
closely-allied Indian wag-tails or Motacillae. Mr. Swinhoe 9
informs me that three species of Ardeola, a genus of her-
ons, which represent each other on separate continents,
are "most strikingly different" when ornamented with
their summer plumes, but are hardly, if at all, distinguish-
able 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 first three
species during the winter and in their immature state ;
and this plumage, which is common to several distinct
species at different ages and seasons, probably shows us

troduction, p. xxix. In regard to Tanysiptera, Prof. Schlcgel told Mr,
Blyth that he could distinguish several distinct races, solely by compar-
ing the adult males.

• See also Mr. Swinhoe, in 'Ibis,' July, 1863, p. 131 ; and a previous
paper, with an extract from a note by Mr. Blyth, in 'Ibis,' Jan. 1861,
p. 52.

Chap. XVI.] THE YOUNG LIKE THE ADULT FEMALES. 183

how the progenitor of the genus was colored. In all these
cases, the nuptial plumage, which we may assume was
originally acquired by the adult males during the breed-
ing-season, and transmitted to the adults of both sexes
at the corresponding season, has been modified, while the
winter and immature plumages have been left unchanged.

The question naturally arises, How is it that in these
latter cases the winter plumage of both sexes, and in the
former cases the plumage of the adult females, as well as
the immature plumage of the young, have not been at all
affected ? The species which represent each other in dis-
tinct countries will almost always have been exposed to
somewhat different conditions, but we can hardly attrib-
ute the modification of the plumage in the males alone to
this action, seeing that the females and the young, though
similarly exposed, have not been affected. Hardly any
fact in Nature shows us mere clearly how subordinate in
importance is the direct action of the conditions of life,
in comparison with the accumulation through selection of
indefinite variations, than the surprising difference be-
tween the sexes of many birds ; for both sexes must 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 ; we see only that this is sub-
ordinate in importance to the accumulated results of se-
lection. When, however, a species migrates into a new
country, and this must precede the formation of represent-
ative species, the changed conditions to which they will
almost always have been exposed will cause them to
undergo, judging from a widely-spread analogy, a certain
amount of fluctuating variability. In this case sexual
selection, which depends on an element eminently liable
to ohange — namely, the taste or admiration <>i the female

— will have had new shades of color or other dith n lu es

184

SEXUAL SELECTION: BIRDS.

[Part II.

to act on and accumulate; and, as sexual selection is
always at work, it would (judging from what we know
of the results on domestic animals of man's unintentional
selection) be a surprising fact if animals inhabiting sepa-
rate districts, which can never cross and thus blend their
newly-acquired characters, were not, after a sufficient
lapse of time, differently modified. These remarks like-
wise apply to the nuptial or summer plumage, whether
confined to the males or common to both sexes.

Although the females of the above closely-allied spe-
cies, together with their young, differ hardly at all from
each other, so that the males alone can be distinguished,
yet in most cases the females of the species within the
same genus obviously differ from each other. The differ-
ences, however, are rarely as great as between the males.
We see this clearly in the whole family of the Gallinaceae :
the females, for instance, of the common and Japan pheas-
ant, and especially of the gold and Amherst pheasant,
of the silver pheasant and the wild-fowl, resemble each
other very closely in color, while the males differ to an
extraordinary degree. So it is with the females of most
of the Cotingidaj, Fringillidae, and many other families.
There can indeed be no doubt that, as a general rule, the
females have been modified to a less extent than the
males. Some few birds, however, offer a singular and
inexplicable exception; thus the females of Paradisea
apoda and P. Papuana differ from each other more than
do their respective males ; 7 the female of the latter spe-
cies having the under surface pure white, while the female
P. apoda is deep brown beneath. So, again, as I hear
from Prof. Newton, the males of two species of Oxy-
notus (shrikes), which represent each other in the islands
of Mauritius and Bourbon,8 differ but little in color, while

1 Wallace, 'The Malay Archipelago,' vol ii. 1869, p. 394.
8 These species are described, with colored figures, by M. F. Pollen,
in 'Ibis,' 1866, p. 275.

Chap. XVL] THE YOUNG LIKE THE ADULT FEMALES. 185

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 which occur,
independently of selection by man, and which we cannot
explain, in certain sub-breeds of the game-fowl, in which
the females are very different, while the males can hardly
be distinguished.9

As I account so largely by sexual selection for the dif-
ferences between the males of allied species, how can the
differences between the females be accounted for in all
ordinary cases ? We need not here consider the species
which belong to distinct genera; for, with these, adapta-
tion to different habits of life, and other agencies, will
have come into play. In regard to the differences be-
tween 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 transference,, in
a greater or less degree, to the female of the characters
acquired by the males through sexual selection. In the
several British finches, the two sexes differ either very
slightly or considerably ; and if we compare the females
of the greenfinch, chaffinch, goldfinch, bullfinch, crossbill,
sparrow, etc., we shall see that they differ from each other
chiefly in the points in which they partially resemble their
respective males ; and the colors of the males may safely
be attributed to sexual selection. With many gallina-
ceous species the sexes differ to an extreme degree, as
with the peacock, pheasant, and fowl, while with other
species there has been a partial or even complete transfer-
ence of character from the male to the female. The fe-
males of the several species of Polypleetron exhibit in a
dim condition, and chiefly on the tail, the splendid ocelli

• 'Variation of Animals, etc., under Domcstkatioii,' fol i. p. 1*5 1 .

180 SEXUAL SELECTION: BIRDS. [Part II.

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 colors being much duller.
In the guinea-fowl the two sexes are undistinguishable.
There is no improbability in the plain, though peculiar
spotted plumage of this latter bird having been acquired
through sexual selection by the males, and then trans-
mitted to both sexes ; for it is not essentially different
from the much more beautifully-spotted plumage, charac-
teristic of the males alone of the Tragopan pheasants.

It should be observed that, in some instances, the trans-
ference of characters from the male to the female has been
effected apparently at a remote period, the male having
subsequently undergone great changes, without transfer-
ring to the female any of his later-gained characters. For
instance, the female and the young of the black-grouse
(Tetrao tetrix) resemble pretty closely both sexes and the
young of the red-grouse (T. JScoticus) ; and we may conse-
quently infer that the black-grouse is descended from
some ancient species, of which both sexes were colored in
nearly the same manner as the red-grouse. As both sexes
of this latter species are more plainly barred during the
breeding-season than at any other time, and as the male
differs slightly from the female in his more strongly-
pronounced red and brown tints,10 we may conclude that
his plumage has been, at least to a certain extent, influ-
enced by sexual selection. 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 shows
in her tail a trace of the curved fork.

" Macgillivray, 1 Hist. British Birds,' vol. i. pp. 172-174.

Chap. XVI.] THE YOUNG LIKE THE ADULT FEMALES. 187

We may therefore conclude that the females of dis-
tinct though allied species have often had their plumage ren-
dered more or less different by the transference, in various
degrees, of characters acquired, both during former and
recent times, by the males through sexual selection. But
it deserves especial attention that brilliant colors have
been transferred much more rarely than other tints. For
instance, the male of the red-throated bluebreast ( Gya-
necula suecica) has a rich blue breast, including a sub-tri-
angular red mark ; now, marks of approximately the same
shape have been transferred to the female, but the central
space is fulvous instead of red, and is surrounded by mot-
tled instead of blue feathers. The Gallinacese offer many
analogous cases ; for none of the species, such as partridges,
quails, guinea-fowls, etc., in which the colors of the plu-
mage have been largely transferred from the male to the fe-
male, are brilliantly colored. This is well exemplified with
the pheasants, in which the male is generally so much more
brilliant than the female ; but with the Eared and Cheer
pheasants (Crossoptilon auritum and JPhasianus Wal-
lichii) the two sexes closely resemble each other, and their
colors are dull. We may go so far as to believe that, if
any part of the plumage in the males of these two pheas-
ants had been brilliantly colored, this 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 nidification, the transference of
bright colors from the male to the female has been cheeked
through natural selection. We must not, however, forget
that another explanation, before given, is possible ; namely,
that the males which varied and became bright, while
they were young and inexperienced, would have been ex-
posed to much danger, and would generally have been
destroyed; the older and more cautious males, on tho
other hand, if they varied in a like manner, would not only

188

SEXUAL SELECTION: BIRDS.

[Part II.

have been able to survive, but would have been favored in
their rivalry with other males. Now, variations occurring
late in life tend to be transmitted exclusively to the same
sex, so that in this case extremely bright tints would not
have been transmitted to the females. On the other hand,
ornaments of a less conspicuous kind, such as those pos-
sessed by the Eared and Cheer pheasants, would not have
been dangerous, and, if they appeared during early youth,
would generally have been transmitted to both sexes.

In addition to the effects of the partial transference of
characters from the males to the females, some of the dif-
ferences between the females of closely-allied species may
be attributed to the direct or definite action of the condi-
tions of life.11 With the males any such action would
generally have been masked by the brilliant colors gained
through sexual selection ; but, not so with the females.
Each of the endless diversities in plumage, which we see
in our domesticated birds, is, of course, the result of some
definite cause ; and, under natural and more uniform con-
ditions, some one tint, assuming that it was in no way in-
jurious, would almost certainly sooner or later prevail
The free intercrossing of many individuals belonging te
the same species would ultimately tend to make any
change of color, thus induced, uniform in character.

No one doubts that both sexes of many birds have had
their colors adapted for the sake of protection; and it is
possible that the females alone of some species may have
been thus modified. Although it would be a difficult, per-
haps an impossible process, as shown in the last chapter,
to convert through selection one form of transmission into
another, there would not be the least difficulty in adapting
the colors of the female, independently of those of the
male, to surrounding objects, through the accumulation

11 See, on this subject, chap, xxiii. in the 'Variation of Animals and
Plants under Domestication.'

Chap. XVI.] THE YOUNG LIKE THE ADULT FEMALES. 189

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 deteri-
orated 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 difficul-
ties. Any variations which were of no service to the
female as a protection would be at once obliterated,
instead of being lost simply by not being selected, or from
free intercrossing, or from being eliminated when trans-
ferred to the male and in any way injurious to him. Thus
the plumage of the female would be kept constant in char-
acter. 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 sex-
ual selection. We ought, however, to be cautious in
concluding that colors, 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-spar-
row, 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 colors, at least in
part, for the sake of protection. We know how well they
are thus concealed; we know that ptarmigans, while
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 and
red grouse serve as a protection ? Are partridges, as they
are now colored, better protected than if they had re-

190

SEXUAL SELECTION: BIRDS.

[Part II.

sembled quails? Do the slight differences between the
females of the common pheasant, the Japan and golden
pheasants, serve as a protection, or might not their plu-
mages have been interchanged with impunity ? From what
Mr. Wallace has observed of the habits of certain gallina-
ceous birds in the East, he thinks that such slight differ-
ences are beneficial. For myself, I will only say that I
am not convinced.

Formerly, when I was inclined to lay much stress on
the principle of protection, as accounting for the less
bright colors of female birds, it occurred to me that pos-
sibly both sexes and the young might aboriginally have
been brightly colored in an equal degree ; but that, subse-
quently, 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 selec-
tion, the females and the young to almost exactly the
same tints and markings, and to transmit them to the cor-
responding sex and period of life. It is also a somewhat
strange fact, 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 colored as the
males, that the females have never been rendered dull-
colored without the young participating in the same
change ; for there are no instances, as far as I can discov-
er, of species with the females dull-colored and the young
bright-colored. 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
afterward either decreases into a mere circular red line in

Chap. XYL] THE YOUNG LIKE THE ADULT MALES. 191

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 varia-
tions in brightness or in other ornamental characters,
occurring in the males at a rather late period of life have,
alone been preserved ; and that most or all of these varia-
tions, owing to the late period of life at which they ap-
peared, have been from the first transmitted only to the
adult male offspring. Any variations in brightness which
occurred in the females or in the young would have been
of no service to them, and would not have been selected;
moreover, if dangerous, would have been eliminated. Thus
the females and the young will either have been left un-
modified, or, and this has much more commonly occurred,
will have been partially modified, by receiving, through
transference from the males, some of the successive varia-
tions. Both sexes have perhaps been directly acted on
by the conditions of life to which they have long been ex-
posed ; but the females, from not being otherwise much
modified, will best exhibit any such effects. These changes
and all others will have been kept uniform by the free in-
tercrossing of many individuals. In some cases, especially
with ground-birds, the females and the young may possi-
bly have been modified, independently of the males, for
the sake of protection, so as to have acquired the same
dull-colored plumage.

Class II. When (he adult female is more conspicuous
than the adult male, the young of both sexes in their first
plumage resemble the adult male. — This class is exactly tho
reverse of the last, for the females are here more brightly

19 Audubon, ' Ornith. Biography,' voL t * 198. Macgilllvray, 'Hist.
Brit. Birds,' vol. iii. p. 85. Sec also tho case before given of Tndopkm
carlotta.

192

SEXtJAL SELECTION: BIRDS. [Part II.

colored or more conspicuous than the males; and the
young, as far as they are known, resemble the adult males
instead of the adult females. But the difference between
the sexes is never nearly so great as occurs with many
birds in the first class, and the cases are comparatively
rare. Mr. Wallace, who first called attention to the singu-
lar relation which exists between the less bright colors of
the males and their performing the duties of incubation,
lays great stress on this point,13 as a crucial test that ob-
scure colors have been acquired for the sake of protection
during the period of nesting. A different view seems to
me more probable. As the cases are curious, and not
numerous, I will briefly give all that I have been able to
find.

In one section of the genus Turnix, quail-like birds, the
female is invariably larger than the male (being nearly
twice as large in one of the Australian species), and this is
an unusual circumstance with the Gallinaceae. In most
of the species the female is more distinctly colored and
brighter than the male,14 but in some few species the sexes
are alike. In Turnix taigoor of India the male u 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 more vociferous,
and is certainly much more pugnacious, than the male ;
so that the females and not the males are often kept by
the natives for fighting, like game-cocks. As male birds
are exposed by the English bird-catchers for a decoy near
a trap, in order to catch other males by exciting their ri-

13 1 Westminster Review, July, 1867, and A. Murray, 1 Journal of
Travel,' 1868, p. 83.

14 For the Australian species, see Gould's ' Hand-book,' etc., vol. ii
pp. 1*78, 180, 186, 188. In*the British Museum specimens of the Aus-
tralian Plain-wanderer (Pedionomus torguatics) may be seen, showing
similar sexual differences.

Chap. XVI.] TIIE YOUNG LIKE THE ADULT MALES. 193

valry, 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 oft*, and any
females within ear-shot run rapidly to the spot, and com-
mence 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.16 Mr.
Blyth believes that the young of both sexes resemble the
adult male.

The females of the three species of Painted Snipes
(Rhynchaea) " are not only larger, but much more richly
colored than the males." 16 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 ffliynchma Australis it is simple in
the male, while in the female it makes four distinct con-
volutions before entering the lungs.17 The female, there-
fore, of this species has acquired an eminently masculine
character. Mr. Blyth ascertained, by examining many
specimens, that the trachea is not convoluted in either sex
of M. Bengalensis, which species so closely resembles It.
Australis that it can hardly be distinguished except by
its shorter toes. This fact is another striking instance of
the law that secondary sexual characters are often widely
different in closely-allied forms ; though it is a very rare
circumstance when such differences relate to the female
sex. The young of both sexes of R. Bengalensis in their

15 Jerdon, 1 Birds of India,' voL iii. p. 596. Mr. Swinhoe, in ' Ibis,'
1865, p. 542; 1866, pp. 131, 405.

16 Jerdon, ' Birds of India.' voL iii. p. 677.

17 Gould's ' Hand-book of the Birds of Australia,' rol. ii. p. 275.

28

194 SEXUAL SELECTION: BIRDS. [Part 11.

first plumage are said to resemble the mature male.18
There is also reason to believe that the male undertakes
the duty of incubation, for Mr. Swinhoe 19 found the fe-

Fig. 60.— Rkynchsea capensis (from Brelrm).

males before the close of the summer associated in flocks,
as occurs with the females of the Turnix.

The females of Phalaropus fulicarius and P. hyperbo-
reus are larger, and in their summer plumage " more gayly

" 'The Indian Field,' Sept. 1858, p. 3.
19 'Ibis,' 1866, p. 298.

Chap. XV I.J THE YOUNG LIKE THE ADULT MALES. 195

attired than the males." But the difference in color be-
tween the sexes is far from conspicuous. The male alone
of P. fulicarim undertakes, according to Prof. Steenstrup, p
the duty of incubation, as is likewise shown by the state
of his breast-feathers during the breeding-season. The
female of the dotterel plover (Midromias morinellus) is
larger than the male, and has the red and black tints on
the lower surface, the white crescent on the breast, and
the stripes over the eyes, more strongly pronounced. The
male also takes at least a share in hatching the eggs ; but
the female likewise attends to the young.20 I have not
been able to discover whether with these species the
young resemble the adult males more closely than the
adult females ; for the comparison is somewhat difficult to
make on account of the double moult.

Turning now to the Ostrich order: the male of the
common cassowary (Casuarius galeatus) would be
thought by any one to be the female, from his smaller
size and from the appendages and naked skin about his
head being much less brightly colored; and I am in-
formed 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.31 The female is said by Mr. T. W.
Wood 22 to exhibit during the breeding-season a most

20 For these several statements, see Mr. Gould's ' Birds of Great Brit-
ain.' Prof. Newton informs me that he has long been convinced, from
his own observations and from those of others, that the males of the
above-named species take either the whole or a large share of the duties
of incubation, and that they " show much greater devotion toward their
young, when in danger, than do the females." So it is, as he informs me,
with Limosa lapponica and some few other "Waders, in which the females
are larger and have more strongly-contrasted colors than the males.

21 The natives of Ceram (Wallace, 'Malay Archipelago,' vol. ii. p. 160)
assert that the male and female sit alternately on the eggs ; but this as-
sertion, as Mr. Bartlett thinks, may be accounted for by the female visit-
ing the nest to lay her eggs.

22 ' The Student,' April, 1870, p. 124.

196 SEXUAL SELECTION: BIRDS. [Part II.

pugnacious disposition ; and her wattles then become en-
larged and more brilliantly colored. So, again, the female
of one of the emus (Dromwus irroratus) is considerably-
larger than the male, and she possesses a slight top-knot,
but is otherwise undistinguishable in plumage. She ap-
pears, 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, gut-
tural 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 incuba-
tion, 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 endeavors to destroy
them. For months afterward it is unsafe to put the par-
ents together, violent quarrels being the inevitable result,
in which the female generally comes off conqueror." 28 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 sav-
age, quarrelsome, and noisy, the males gentle and good.
The case is very different with the African ostrich, for the
male is somewhat larger than the female and* has finer
plumes with more strongly-contrasted colors ; neverthe-
less, he undertakes the whole duty of incubation.24

I will specify the few other cases known to me, in
which the female is more conspicuously colored than the
male, although nothing is known about their manner of

23 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.

24 Mr. Sclater, on the incubation of the Struthiones, ' Proc. Zool. Soc.,'
June 9, 1863.

Chap. XVI.] THK YOUNG LIKE THE ADULT MALES. 197

incubation. With the carrion-hawk of the Falkland Isl-
ands (Milvayo leuOtirtts) I was much surprised to find by
dissection that the Individuals, which bad all their tints
strongly pronounced, with the cere and legs orange-col-
ored, were the adult females; while those with duller
plumage and gray legs were the males or the young. In
an Australian tree-creeper {CUmacteris erythrops) the fe-
male differs from the male in "being adorned with beauti-
ful, radiated, rufous markings on the throat, the male hav-
ing this part quite plain/1 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." M

We thus see that the cases in which female birds are
more conspicuously colored than the males, with the
young in their immature plumage resembling the adult
males instead of the adult females, as in the previous class,
are not numerous, though they are distributed in various
Orders. The amount of difference, also, between the sexes
is incomparably less than that which frequently occurs in

55 For the Milvago, see 1 Zoology of the Voyage of the Beagle,'
Birds, 1841, p. 16. For the Climacteris and night-jar (Eurostopodus),
see Gould's 1 Hand-book of the Birds of Australia,' vol. i. pp. 602, 97.
The New Zealand shieldrake ( Tadorna variegata) offers a quite anomalous
case : the head of the female i3 pure white, and her back is redder than
that of the male ; the head of the male is of a rich dark bronzed color,
and his back is clothed with finely-pencilled slate-colored feathers, so
that he may altogether 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 ('Proc. 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, while the males and the young have
retained a former state of plumage.

198

SEXUAL SELECTION: BIRDS.

[Part II,

the last class ; so that the cause of the difference, what-
ever it may have been, has acted on the females in the
present class either less energetically or less persistently
than on the males in the last class. Mr. Wallace believes
that the males have had their colors rendered less conspic-
uous for the sake of protection during the period of incu-
bation ; 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 colored, would not
have been exposed to danger while sitting on the eggs.
It should also be borne in mind that the males are not
only in a slight degree less conspicuously colored than the
females, but are of less size, and have less strength. 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 or-
gans. Thus an almost complete transposition of the
instincts, habits, disposition, color, 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 ardor which is usual to their
sex, so that they no longer search eagerly for the females ;
or, if we might assume that the females have become
much more numerous than the males — and in the case of
one Indian Turnix the females are said to be " much more
commonly met with than the males " 26 — then it is not im-
probable that the females would have been led to court
the males, instead of being- courted by them. This, indeed,
is the case to a certain extent, with some birds, as we
have seen with the peahen, wild-turkey, and certain kinds
of grouse. Taking as our guide the habits of most male
26 Jerdon, 1 Birds of India,' vol. iii. p. 598.

Chap. XVI. | T1IK VOI NC I.IK K IK) Til ADULTS.

1!)!)

birds, the greater Bin and strength and the extraordinary
pugnacity of the females of the Turnix and Emu, must
mean that they endeavor to drive away rival females, in
order to gain possession of the male; and on this view,
all the facta become clear; for the males would probably
be most charmed or excited by the females which were
the most attractive to them by their brighter colors, other
ornaments, or vocal powers. Sexual selection would then
■OOD do its work, steadily adding to the attractions of the
females; the males and the young being left not at all, or
but little modified.

Class III. — When the adult male resembles the adult
female, the young of both sexes have a peculiar first jylio-
mar/e of their oica. — In this class both sexes when adult
resemble each other, and differ from the young. This
occurs with many birds of many kinds. The male robin
can hardly be distinguished from the female, but the
young are widely different with their mottled dusky-olive
and brown plumage. The male and female of the splen-
did scarlet Ibis are alike, while the young are brown; and
the scarlet color, though common to both sexes, is appar-
ently a sexual character, for it is not well developed with
birds under confinement, in the same manner as often oc-
curs in the case of brilliantly-colored male birds. With
many species of herons the young differ greatly from the
adults, and their summer plumage, though common to both
sexes, clearly has a nuptial character. Young swans are
slate-colored, while the mature birds are pure white ; but it
would be superfluous to give additional instances. These
differences between the young and the old apparently de-
pend, as in the last two classes, on the young having
retained a former or ancient state of plumage, which has
been exchanged for a new plumage by the old of both
sexes. When the adults are brightly colored, we may
conclude from the remarks just made in relation to the

200

SEXUAL SELECTION: BIRDS.

[Part II.

scarlet ibis and to many herons, and from the analogy of
the species in the first class, that such colors 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
both sexes, when mature, resemble each other and differ
from the young.

Class IV. When the adult male resembles the adult
female, the young of both sexes in their first plumage
resemble the adults. — In this class the young and the
adults of both sexes, whether brilliantly' or obscurely
colored, 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-colored birds,
such as the hedge-warbler or kitty-wren. But the simi-
larity in plumage between the young and the old is never
absolutely complete, and graduates away into dissimilari-
ty. Thus the young of some members of the kingfisher
family are not only less vividly colored than the adults,
but many of the feathers on the lower surface are edged
with brown 27 — 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 parrokeets (Platycercus), the young of some species
closely resemble, while the young of other species differ
considerably from their parents of both sexes, which are
alike.28 Both sexes and the young of the common jay are
closely similar ; but in the Canada jay (Perisoreus Cana-
densis) the young differ so much from their parents that
they were formerly described as distinct species.29

27 Jerdon, 'Birds of India,' vol. i. pp. 222, 228. Gould's 'Hand-book
of the Birds of Australia,' vol. i. pp. 124, 130.

28 Gould, Ibid. vol. ii. pp. 37, 46, 56.

29 Audubon, ' Ornith. Biography,' vol. ii. p. 65.

Chap. XVI.] THE YOUNG LIKE BOTH ADULTS.

201

Before proceeding, I may remark that under the pres-
ent and two next classes of cases the facts are so complex,
ami the conelusions so doubtful, that any one who feels
no especial interest in the subject had better pass them
over.

The brilliant or conspicuous colors which characterize
many b,irds in the present class, can rarely or never be of
service to them as a protection; so that they have prob-
ably been gained by the males through sexual selection,
and then transferred to the females and the young. It is,
however, possible that the males may have selected the
more attractive females; and if these transmitted their
characters to their offspring of both sexes, the same re-
sults would follow as from the selection of the more at-
tractive males by the females. But there is some 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 exceeded to a slight degree the males in beauty.
Exactly the reverse occurs under nature ; for in almost
every large group, in which the sexes generally resemble
each other, the males of some few species are in a slight
degree more brightly colored than the females. It is
again possible that the females may have selected the
more beautiful males, these males having reciprocally
selected the more beautiful females; but it is doubtful
whether this double process of selection would be likely
to occur, owing to the greater eagerness of one sex than
the other, and whether it would be more efficient than
selection on one side alone. It is, therefore, the most
probable view that sexual selection has acted, in the pres-
ent class, as far as ornamental characters are concerned, in
accordance with the general rule throughout the animal
kingdom, that is, on the males; and that these have

202

SEXUAL SELECTION: BIRDS. [Part II.

transmitted their gradually-acquired colors, either equally
or almost equally, to their offspring of both sexes.

Another point is more doubtful, namely, whether the
successive variations first appeared in the males after they
had become nearly mature, or while quite young. In
either case sexual selection must have acted on the male
when he had to compete with rivals for the possession of
the female ; and in both cases the characters thus acquired
have been transmitted to both sexes and all ages. But
these characters, if acquired by the males when adult, may
have been transmitted at first to the adults alone, and at
some subsequent period transferred to the young. For
it is known that when the law of inheritance at corre-
sponding ages fails, the offspring often inherit characters
at an earlier age than that at which they first appeared in
their parents.30 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
Golymbus glacialis which had assumed while young, in a
quite anomalous manner, the adult plumage of their
parents.81 Again, the young of the common swan (Cyg-
nus olor) do not cast off their dark feathers and become
white until eighteen months or two years old ; but Dr. F.
Forel has described the case of three vigorous young
birds, out of a brood of four, which were born pure white.
These young birds were not albinoes, as shown by the
color of their beaks and legs, which nearly resembled the
same parts in the adults.32

30 ' Variation of Animals and Plants under Domestication,' vol. ii.
p. 79.

31 Charlesworth, 'Mag. of Nat. Hist.' vol. i. 1837, pp. 305, 306.

32 ' Bulletin de la Soc. Vaudoise des Sc. Nat.' vol. x. 1869, p. 132.
The young of the Polish swan, Cygnus immutabilis of Yarrell, are always
white; but this species, as Mr. Sclater informs me, is believed to be
uothing more than a variety of the Domestic Swan ( Cygnus olor).

Cuap. xvi.] Tin: Yor\<; likk both adults.

203

It may be worth while to illustrate the above three
modes by which, in the present class, the two sexes mid
the young may have eome to resemble each other, by
the curious case of the genus Passer.33 In the house-spar-
row (P. dome»Heus) the male differs much from the fe-
male and from the young. These resemble each other,
and likewise to a large extent both sexes and the young
of the sparrow of Palestine (P. br achy dactyl us), as well
as of some allied species. We may therefore assume that
the female and young of the house-sparrow approximately
show us the plumage of the progenitor of the genus.
Now with the tree-sparrow (P. nwntanus) both sexes and
the young closely resemble the male of the house-sparrow ;
so that they have all been modified in the same manner,
and all depart from the typical coloring of their early pro-
genitor. This may have been effected by a male ancestor
of the tree-sparrow having varied, firstly, when nearly ma-
ture, or, secondly, while quite young, having in either case
transmitted his modified plumage to the females and the
young ; or, thirdly, he may have varied when adult and
transmitted his plumage to both adult sexes, and, owing
to the failure of the law of inheritance at corresponding
ages, at some subsequent period to his young.

It is impossible to decide which of these three modes
has generally prevailed throughout the present class of
cases. The belief that the males varied while young, and
transmitted their variations to their offspring of both
sexes, is perhaps the most probable. I may here add that
I have endeavored, with little success, by consulting vari-
ous wrorks, to decide how far with birds the period of vari-
ation has generally determined the transmission of charac-
ters to one sex or to both. The two rules, often referred
to (namely, that variations occurring late in life are

83 1 am indebted to Mr. Blyth for information in regard to this genus.
The sparrow of Palestine belongs to the sub-genus Petronia.

204

SEXUAL SELECTION: BIRDS.

[Part II.

transmitted to one and the same sex, while those which
occur early in life are transmitted to both sexes), ap-
parently hold good in the first,34 second, and fourth classes
of cases ; but they fail in an equal number, namely, in the
third, often in the fifth,86 and in the sixth small class.
They hold good, however, as far as I can judge, with a
considerable majority of the species of birds. Whether
or not this be so, we may conclude from the facts given
in the eighth chapter that the period of variation has
been one important element in determining the form of
transmission.

With birds it is difficult to decide by what standard
we ought to judge of the earliness or lateness of the period
of variation, whether by the age in reference to the du-
ration of life, or to the power of reproduction, or to the
number of moults through which the species passes. The
moulting of birds, even within the same family, sometimes
differs much without any assignable cause. Some birds
moult so early, that nearly all the body-feathers are cast
off before the first wing-feathers are fully grown ; and we
cannot believe that this was the primordial state of things.
When the period of moulting has been accelerated, the
age at which the colors of the adult plumage were first
developed would falsely appear to us to have been earlier

34 For instance, the males of Tanagra cestiva and Frivgilla cyanea re-
quire three years, the male of Fringilla ciris four years, to complete their
beautiful plumage. (See Audubon, 1 Ornith. Biography,' vol. i. pp. 233,
280, 378.) The Harlequin duck takes three years (ibid. vol. iii. p. 614).
The male of the Gold pheasant, as I hear from Mr. J. Jenner Weir, can
be distinguished from the female when about three months old, but he
does not acquire his full splendor until the end of the September in the
following year.

35 Thus the Ibis tantalus and Grus Americanus take four years, the
Flamingo several years, and the Ardea Ludovicana two years, before they
acquire their perfect plumage. See Audubon, ibid. vol. i. p. 221 ; vol.
iii. pp. 133, 139, 211.

Chap. XVI. J THE YOUNG LIKE BOTH ADL'LTS.

than it really was. This may be illustrated by the practice
followed l>y sonic bird-fanciers, who pull out a few leathers
from the breast* of nestling bullfinches, and from the head
or neck of young gold-pheasants, in order to ascertain their
sex; for in the males these leathers are immediately re-
placed by colored ones.39 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 powers of reproduction are gained, it is a remarkable
fart that various birds occasionally breed while retaining
their immature plumage."

The fact of birds breeding in their immature plumage
seems opposed to the belief that sexual selection has played
as important a part as I believe it has in giving ornament-
al colors, plumes, etc., to the males, and, by means of
equal transmission, to the females of many species. The
objection would be a valid one, if the younger and less
ornamented males were as successful in winning females
and propagating their kind, as the older and more beauti-
ful males. But we have no reason to suppose that this is

•

36 Mr. Blyth, in Charlesworth's 4 Mag. of Nat. Hist.' vol i. 1837, p.
300. Mr. Bartlett ha9 informed me in regard to gold-pheasants.

31 I have noticed the following cases in Audubon's ' Ornith. Biogra-
phy. The Redstart of America' (Muscicapa ruiicilla, vol. i. p. 203).
The Ibis tantalus takes four years to come to full maturity, but sometimes
breeds in the second year (vol. iii. p. 133). The Grus Arnericanus takes
the same time, but breeds before acquiring its full plumage (vol. iii. p.
211). The adults of Ardea ccerulea are blue and the young white; and
white, mottled, and mature blue birds may all be seen breeding together
(vol. iv. p. 58) : but Mr. Blyth informs me that certain herons apparently
are dimorphic, for white and colored individuals of the same age may be
observed. The Harlequin duck (Anas histrionica, Linn.) takes three
years to acquire its full plumage, though many birds breed in the second
year (voL iii. p. 614). The Whiteheaded Eagle (Falco leucocephalus, vol.
iii. p. 210) is likewise known to breed in its immature state. Some spe-
cies of Oriolus (according to Mr. Blyth and Mr. Swinhoe, in • Ibis,' July
1863, p. 68) likewise breed before they attain their full plumage.

206

SEXUAL SELECTION: BIRDS. [Part II.

the case. Audubon speaks of the breeding of the imma-
ture males of Ibis tantalus as a rare event, as does Mr.
Swinhoe, in regard to the immature males of Oriolus.38 If
the young of any species in their immature plumage were
more successful in winning partners than the adults, the
adult plumage would probably soon be lost, as the males
which retained their immature dress for the longest period
would prevail, and thus the character of the species would
ultimately be modified.39 If, on the other hand, the young
never succeeded in obtaining a female, the habit of early
reproduction would perhaps be sooner or later quite elim-
inated, from being superfluous and entailing waste of
power.

The plumage of certain birds goes on increasing in
beauty during many years after they are fully mature ;
this is the case with the train of the peacock, and with
the crest and plumes of certain herons ; for instance, the
Ardea Imdovicana / 40 but it is very doubtful whether
the continued development of such feathers is the result of

38 See the last foot-note.

39 Other animals, belonging to quite distinct classes, are either habit-
ually or occasionally capable of breeding before they have fully acquired
their adult characters. This is the case with the young males of the
salmon. Several amphibians have been known to breed while retaining
their larval structure. Fritz Miiller has shown (' Facts and Arguments
for Darwin,' Eng. Trans. 1869, p. 79) that the males of several amphipod
crustaceans become sexually mature while young ; and I infer that this
is a case of premature breeding, because they have not as yet acquired
their fully-developed claspers. All such facts are highly interesting, as
bearing on one means by which species may undergo great modifications
of character, in accordance with Mr. Cope's views, expressed under the
terms of the " retardation and acceleration of generic characters ; " but
I cannot follow the views of this eminent naturalist to their full extent.
See Mr. Cope, " On the Origin of Genera," from the ' Proc. of Acad. Nat.
Sc. of Philadelphia/ Oct. 1868.

40 Jerdon, 1 Birds- of India,' vol. iii. p. 507, on the peacock. Audu-
bon, ibid. vol. iii. p. 139, on the Ardea.

QUA XVI.] SEASONAL CHANGES OF PLUMAGE.

20?

the selection of successive beneficial. variations, or merely
of continuous growth. Most fishes continue increasing in
size, as long as they are in good health and have plenty
of food; and a somewhat similar law may prevail with
the plumes of birds.

Class V. W/ie?i the adults of both sexes have a dis-
tinct 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 gnatly from the adults in both
their seasonal phmutges, — The cases in this class are
singularly complex ; nor is this surprising, as they depend
on inheritance, limited in a greater or less degree in three
different ways, namely, by sex, age, and the season of the
year. In some cases the individuals of the same species
pass through at least five distinct states of plumage.
With the species, in which the male differs from the
female during the summer season alone, or, which is rarer,
during both seasons,41 the young generally resemble the
females — as with the so-called goldfinch of North Amer-
ica, and apparently with the splendid Maluri of Aus-
tralia.42 With the species, the sexes of which are alike
during both the summer and winter, the young may re-
semble the adults, firstly, in their winter dress ; secondly,
which occurs much more rarely, in their summer dress ;
thirdly, they may be intermediate between these two
states; and, fourthly, they may differ greatly from the

41 For illustrative cases see vol. iv. of Macgillivray's ' Hist. Brit.
Birds;' on Tringa, etc., pp. 229, 2*71 ; on the Machetes, p. 172; on the
Charadrius hiaticula, p. 118; on the Charadrius pluvialis, p. 94.

42 For the goldfinch of North America, Fringilla tristis, Linn., see Au-
dubon, 1 Ornith. Biography,' vol. i. p. 1*72. For the Maluri, Gould's 1 Hand-
book of the Birds of Australia,' vol. i. p. 318.

208

SEXUAL SELECTION: BIRDS. [Part II.

adults at all seasons. We have an instance of the first of
these four cases in one of the egrets of India {Buphus
coromandus), in which the young and the adults of both
sexes are white during the winter, the adults becoming
golden-buff during the summer. With the Gaper (Anas-
tomus oscitans) of India we have a similar case, but the
colors are reversed ; for the young and the adults of both
sexes are gray and black during the winter, the adults be-
coming white during the summer.43 As an instance of the
second case, the young of the razor-bill (Alca torda,
Linn.), in an early state of plumage, are colored like the
adults during the summer ; and the young of the white-
crowned sparrow of North America (Fringilla leuco-
phrys), as soon as fledged, have elegant white stripes on
their heads, which are lost by the young and the old dur-
ing the winter.44 With respect to the third case, namely,
that of the young having an intermediate character be-
tween the summer and winter adult plumages, Yarrell 46
insists that this occurs with many waders. Lastly, in re-
gard to the young differing greatly from both sexes in
their adult summer and winter plumages, this occurs with
some herons and egrets of North America and India — the
young alone being white.

I will make only a few remarks on these complicated
cases. When the young resemble the female in her sum-
mer dress, or the adults of both sexes in their winter
dress, the cases differ from those given under Classes I.
and III. only in the characters originally acquired by the

43 I am indebted to Mr. Blyth for information in regard to the
Buphus: see also Jerdon, 'Birds of India,' vol. iii. p. 749. On the
Anastomus, see Blyth, in 1 Ibis,' 1867, p. 173.

44 On the Alea, see MacgiUivray, 1 Hist. Brit. Birds,' voL v. p. 347.
On the Fringilla leucophrys, Audubon, ibid. vol. ii. p. 89. I shall have
hereafter to refer to the young of certain herons and egrets being white.

45 'History of British Birds,' vol. i. 1839, p.* 159.

Chap. XVI.] THE YOUNG LIKE ADULTS OF SAME SEX. ^09

males during the breeding-season having been limited in
their transmission to the corresponding season. When
the adults have a distinet summer and winter plumage,
and the young differ from both, the case is more difficult
to understand. We may admit as probable that the
young have retained an ancient state of plumage ; we can
aeeount through sexual selection for the summer or nup-
tial plumage of the adults, but how are we to account for
their distinct winter plumage? If we could admit that
this plumage serves in all cases as a proteetion, its ac-
quirement would be a simple affair ; but there seems no
good reason for this admission. It may be suggested that
the widely-different conditions of life during the winter
and summer have acted in a direct manner on the plu-
mage; this may have had some effect, but I have not
much confidence in so great a difference, as we sometimes
see, between the two plumages having been thus caused.
A more probable explanation is, that an ancient style of
plumage, partially modified through the transference of
some characters from the summer plumage, has been re-
tained by the adults during the winter. Finally, all the
cases in our present class apparently depend on charac-
ters acquired by the adult males, having been variously
limited in their transmission according to age, season, and
sex ; but it would not be worth while to attempt to fol-
low out these complex relations.

Class VI. The young in their first plumage differ
from each other according to sex ; the young males re-
sembling more or less closely the adult males, and the
young females more or less closely the adult females. —
The cases in the present class, though occurring in vari-
ous groups, are not numerous ; yet, if experience had not
taught us to the contrary, it seems the most natural thing
that the young should at first always resemble to a cer-
tain extent, and gradually become more and more like, the

210

SEXUAL SELECTION : BIRDS.

[Part II.

adults of the same sex. The adult male blackcap {Sylvia
atricapilla) has a black head, that of the female being
reddish-brown ; and I am informed by Mr. Blyth that
the young of both sexes can be distinguished by this
character even as nestlings. In the family of thrushes an
unusual number of similar cases have been noticed ; the
male blackbird {Tardus merula) can be distinguished in
the nest from the female, as the main wing-feathers, which
are not moulted so soon as the body-feathers, retain a
brownish tint until the second general moult.46 The two
sexes of the mocking-bird {Turdus polyglottus, Linn.) dif-
fer very little from each other, yet the males can easily
be distinguished at a very early age from the females by
showing more pure white.47 The males of a forest-thrush
and of a rock-thrush (viz., Orocetes erythrogastra and Pe-
trocincla cyaned) have much of their plumage of a fine
blue, while the females are brown ; and the nestling males
of both species have their main wing and tail feathers
edged with blue, while those of the female are edged with
brown.48 So that the very same feathers which in the
young blackbird assume their mature character and be-
come black after the others, in these two species assume
this character and become blue before the others. The
most probable view with reference to these cases is that
the males, differently from what occurs in Class I., have
transmitted their colors to their male offspring at an ear-
lier age than that at which they themselves first acquired
them; for if they had varied while quite young, they
would probably have transmitted all their characters to
their offspring of both sexes.49

46 Blyth, in Charlesworth's ' Mag. of Nat. Hist.' vol. i. 183*7, p. 362 ;
and from information given to me by him.

47 Audubon, 'Ornith. Biography,' vol. i. p. 113.

48 Mr. C. A. Wright, in 'Ibis,' vol. vi. 1864, p. 65. Jerdon, 'Birds
of India,' vol. i. p. 515.

49 The following additional cases may be mentioned : the young males

Thai-. XVI.] THE YOUNG LIKE ADULTS OF SAME SEX. 211

In A'ithurus jwlytmus (one of the humming-birds) the
male is splendidly colored black and green, and two of
the tail-feathers are immensely lengthened; the female
has an ordinary tail and inconspicuous colors ; now the
young males, instead of resembling the adult female, in
accordance with the common rule, begin from the first to
assume the colors proper to their sex, and their tail-feat h-
ers soon become elongated. I owe this information to
Mr. Gould, who has given me the following more striking
and as yet unpublished case : Two humming-birds be-
longing to the genus Eustephanus, both beautifully col-
ored, inhabit the small island of Juan Fernandez, and
have always been ranked as specifically distinct. But it
has lately been ascertained that the one, which is of a rich
chesnut-brown color with a golden-red head, is the male,
while the other, which is elegantly variegated with green
and white, with a metallic-green head, is the female. Now
the young from the first resemble to a certain extent the
adults of the corresponding sex, the resemblance gradu-
ally becoming more and more complete.

In considering this last case, if as before we take the
plumage of the young as our guide, it would appear that
both sexes have been independently rendered beautiful ;
and not that the one sex has partially transferred its
beauty to the other. The male apparently has acquired
his bright colors through sexual selection in the same man-
ner as, for instance, the peacock or pheasant in our first
class of cases ; and the female in the same manner as the
female Rhynchsea or Turnix in our second class of cases.
But there is much difficulty in understanding how this

of Tanagra rubra can be distinguished from the young females (Audu-
bon, ' 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. 389). Mr. Blyth also informs me that the sexes of the stone-
chat, SazicoJa rubicola, are distinguishable at a very early age.

212

SEXUAL SELECTION: BIRDS.

[Part II.

could have been effected at the same time with the two
sexes of the same species. Mr. Salvin states, as we have
seen in the eighth chapter, that with certain humming-
birds the" males greatly exceed in number the females,
while with other species inhabiting the same country the
females greatly exceed the males. If, then, we might as-
sume that during some former lengthened period the males
of the Juan Fernandez species had greatly exceeded the
females in number, but that during another lengthened
period the females had greatly exceeded the males, we
could understand how the males at one time, and the
females at another time, might have been rendered beauti-
ful by the selection of the brighter-colored individuals of
either sex; both sexes transmitting their characters to
their young at a rather earlier age than usual. Whether
this is the true explanation I will not pretend to say ; but
the case is too- remarkable to be passed over without
notice.

We have now seen in numerous instances, under all
six classes, that an intimate relation exists between the
plumage of the young and that of the adults, either of one
sex or both sexes. These relations are fairly well ex-
plained on the principle that one sex — this being in the
great majority of cases the male — first acquired through
variation and sexual selection bright colors or other orna-
ments, and transmitted them in various ways, in ac-
cordance with the recognized laws of inheritance. Why
variations have occurred at different periods of life, even
sometimes with the species of the same group, we do not
know ; but with respect to the form of transmission, one
important determining cause seems to have been the age
at which the variations first appeared.

From the principle of inheritance at corresponding
ages, and from any variations in color which occurred in the

Ciiap. XVI.]

COLOR AND PROTECTION

213

males at an early age not being then selected, on the con-
trary being often eliminated as dangerous, while 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 sonic insight into the coloring 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 both are brightly colored, at least during
the "breeding-season, while the young are invariably less
brightly colored than the adults, or are quite dull-colored;
for no instance is known, as far as lean discover, of the
young of dull-colored species displaying bright colors, or
of the young of brightly-colored species being more bril-
liantly colored 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)
brightly-colored, and as these form whole groups we may
infer that their early progenitors were likewise brightly-
colored. With this exception, if we look to the birds of
the world, it appears , that their beauty has been greatly
increased since that period, of which we have a partial
record in their immature plumage.

On the Color of the Plumage in relation to Protection.
— It will have been seen that I cannot follow Mr. Wallace
in the belief that dull colors 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
colors modified for this purpose, so as to escape the notice
of their enemies ; or, in some instances, so as to approach
their prey unobserved, in the same manner as owls have
had their plumage rendered soft, that their flight may not
be overheard. Mr. Wallace remarks50 that " it is only in

50 'Westminster Review,' July, 1867, p. 5.

214 SEXUAL SELECTION: BIRDS. [Paet II.

the tropics, among forests that never lose their foliage, that
we find whole groups of birds whose chief color is green."
It will be admitted by every one, who has ever tried, how
difficult it is to distinguish parrots in a leaf-covered tree.
Nevertheless, we must remember that many parrots are
ornamented with crimson, blue, and orange tints, which
can hardly be protective. Woodpeckers are eminently
arboreal, but, besides green species, there are many black
and black-and-white kinds — all the species being appar-
ently exposed to nearly the same dangers. It is there-
fore probable that strongly-pronounced colors have been
acquired by tree-haunting birds through sexual selection,
but that green tints have had an advantage through nat-
ural selection over other colors for the sake of protection.

In regard to birds which live on the ground, every one
admits that they are colored so as to imitate the surround-
ing surface. How difficult it is to see a partridge, snipe,
woodcock, certain plovers, larks, and night-jars, when
crouched on the ground ! Animals inhabiting deserts offer
the most striking instances, for the bare surface affords no
concealment, and all the smaller quadrupeds, reptiles, and
birds, depend for safety on their colors. As Mr. Tristram
has remarked,61 in regard to the inhabitants of the Saha-
ra, all are protected by their " isabelline or sand-color."
Calling to my recollection the desert-birds which I had
seen in South America, as well as most of the ground-
birds in Great Britain, it appeared to me that both sexes
in such cases are generally colored nearly alike. Ac-
cordingly, I applied to Mr. Tristram, with respect to the
birds of the Sahara, and he has kindly given me the fol-
lowing information : There are twenty-six species, belong-
ing to fifteen genera, which manifestly have had their
olumage colored in a protective manner ; and this coloring
?s all the more striking, as with most of these birds it is

51 'Ibis,' 1859, vol. i. p. 429, et seq.

Chap. XVI ] COLOR AND PROTECTION. 215

•

different from that of their conveners. I»oth sexes of thir-
teen out of the twenty-six species are colored in the same
manner; but these belong to genera in which this rule
commonly prevails, so that they tell us nothing about the
protective colors 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 they have the sexes alike. In the remaining ten spe-
cies, 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-colored hue in
both 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;
while the lower surfaces of the males alone have been
diversified through sexual selection, for the sake of orna-
ment. Here, as both sexes are equally well protected, we
clearly see that the females have not been prevented
through natural selection from inheriting the colors of
their male parents : we must look to the law of sexually-
limited transmission, as before explained.

In all parts of the world both sexes of many soft-billed
birds, especially those which frequent reeds or sedges, are
obscurely colored. No doubt, if their colors had been
brilliant, they would have been much more conspicuous to
their enemies; but whether their dull tints have been spe-
cially 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-colored, often differ much from their
females, as with the common sparrow, and this leads to
the belief that such colors have been gained through sex-
ual selection, from being attractive. Many of the soft-

216 SEXUAL SELECTION: BIRDS [Part II.

billed birds are songsters ; and a discussion in a former
chapter should not be forgotten, in which it was shown
that the best songsters are rarely ornamented with bright
tints. It would appear that female birds, as a general
rule, have selected their mates either for their sweet voices
or gay colors, but not for both charms combined. Some
species which are manifestly colored for the sake of pro-
tection, such as the jack-snipe, woodcock, and night-jar,
are likewise marked and shaded, according to our stand-
ard of taste, with extreme elegance. In such cases we
may conclude that both natural and sexual selection have
acted conjointly for protection and ornament. Whether
any bird exists which does not possess some special at-
traction, by which to charm the opposite sex, may be
doubted. When both sexes are so obscurely colored, that
it would be rash to assume the agency of sexual selection,
and when no direct evidence can be advanced showing
that such colors serve as a protection, it is best to own
complete ignorance of the cause, or, which comes to nearly
the same thing, to attribute the result to the direct action
of the conditions of life.

There are many birds both sexes of which are conspic-
uously though not brilliantly colored, such as the numer-
ous black, white, or piebald species ; and these colors are
probably the result of sexual selection. With the common
blackbird, capercailzie, black-cock, black Scoter-duck (Oi-
demia), and even with one of the Birds of Paradise
(Zophorina atra), the males alone are black, while 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 proba-
ble 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

Chap. XYI.] CONSPICUOUS COLORS. 217

both sexes ; for blackness can hardly serve in any case as
a protection. With several birds, in which the male alone
is black, and in others in which both sexes are black, the
beak or skin about the head is brightly colored, and the
contrast thus afforded adds greatly to their beauty ; we
B6G 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 variously and brightly colored beak
of the Scoter-drake (Oidemia), in the red beak of the
chough (Corvus graculits, Linn.), of the black swan, and
black stork. This leads me to remark that it is not at all
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 color with which these
organs are ornamented." The naked skin at the base of
the beak and round the eyes is likewise often brilliantly
colored ; and Mr. Gould, in speaking of one species,63 says
that the colors of the beak " are doubtless in the finest
and most brilliant state during the the time of pairing."
There is no greater improbability in toucans being encum-
bered with immense beaks, though rendered as light as
possible by their cancellated structure, for an object false-
ly appearing to us unimportant, namely, the display of
fine colors, than that the male Argus pheasant and some

52 No satisfactory explanation has ever been offered of the immense
size, and still less of the bright colors, of the toucan's beak. Mr. Bates
(' The Naturalist on the Amazons,' vol. ii. 1863, p. 341) states that they
use their beak for reaching fruit at the extreme tips of the branches ;
and likewise, as stated by other authors, for extracting eggs and young
birds from the nests of other birds. But, as Mr. Bates admits, the beak
" can scarcely be considered a very perfectly-formed instrument for the
end to which it is applied." The great bulk of the beak, as shown by
its breadth, depth, as well as length, is not intelligible on the view that
it serves merely as an organ of prehension.

63 Ramphastos carinatus, Gould's ' Monograph of Ramphastidae.'
29

218

SEXUAL SELECTION : BIRDS. [Paut II.

other birds should be encumbered with plumes so long as
to impede their flight.

In the same manner, as the males alone of various spe-
cies are black, the females being dull-colored ; so in a few
cases the males alone are either wholly or partially white,
as with the several Bell-birds of South America (Chasmo-
rhynchus), the Antarctic goose (Bcrnicla antarctica), the
silver- pheasant, etc., while the females are brown or ob-
scurely mottled. Therefore, on the same principle as
before, it is probable that both sexes of many birds, such
as white cockatoos, several egrets with their beautiful
plumes, certain ibises, gulls, terns, etc., have acquired
their more or less completely white plumage through sex-
ual selection. The species which inhabit snowy regions
of course come under a different head. The white plu-
mage of some of the above-named birds appears in both
sexes only when they are mature. This is likewise the
case with certain gannets, tropic-birds, etc., and with the
snow-goose (A?iser 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 case of the Anastomus
oscitans previously alluded to, we have still better evi-
dence that the white plumage is a nuptial character, for it
is developed only during the summer; the young in their
immature state, and the adults in their winter dress, being
gray and black. With many kinds of gulls (Lanu), the
head and neck become pure white during the summer,
being gray or mottled during the winter and in the young
state. On the other hand, with the smaller gulls, or sea-
mews (Gavia), and with some terns (Sterna), exactly the
reverse occurs ; for the heads of the young birds during
the first year, and of the adults during the winter, are
either pure white, or much paler-colored than during the

Chap. XVI.]

CONSPICUOUS COLORS.

219

breeding-season. These latter cases offer another instance
of the capricious manner in which sexual selection appears
often to have acted.64

The cause of aquatic birds having acquired a white
plumage so much more frequently than terrestrial birds,
probably depends on their large size and strong powers
of flight, so that they can easily defend themselves or es-
cape 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 pro-
tection. 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 per-
fectly white, or intensely black ; so that these colors may
possible 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 carcass 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 of distinct species, to the
prey; but as this would be a disadvantage to the first
finders, the individuals which were the whitest or blackest
would not thus have procured more food than the less
strongly colored individuals. Hence conspicuous colors
caiHiot have been gradually acquired for this purpose
tli rough natural selection."

As sexual selection depends on so fluctuating an cle-

M On Lftroi, Gavia, and Sterna, Bee Macgillivray, 'Hist. Brit, Birds,'
vol. v. pp. 615, 584, 626. On the Anaer hyperboreus, Audubon, * Ornith.
Biography,' vol. to. p. 662. On the Anastomus, Mr. Blyth, in 'll>is,'
18(17, p. 17:?.

"It nay bt noticed that with vultures, whioh roam far and wida

through the higher regions of the atmosphere, like marine birdl Qftl
the ocean, three or four Rpeclea aro almost wholly or largely while, MM)
many other species are blaok. This fact lupporti 1 1 » * * conjecture that

these COnnpicuoilH colors inn v aid the sexes in finding cm h oilier during

the braeding-ccason.

220

SEXUAL SELECTION: BIRDS.

[Taut II.

mcnt as taste, we can understand how it is that within the
same group of birds, with habits of life nearly the same,
there should exist white or nearly white, as well as black,
or nearly black species — for instance, white and black
cockatoos, storks, ibises, swans, terns, and petrels. Pie-
bald birds likewise sometimes occur in the same groups,
for instance, the black-necked swan, certain terns, and the
common magpie. That a strong contrast in color is agree-
able to birds, we may conclude, by looking through any
large collection of specimens or series of colored plates,
for the sexes frequently differ from each other in the male
having the pale parts of a purer white, and the variously-
colored dark parts of still darker tints than in the female.

It would even appear that mere novelty, or change for
the sake of change, has sometimes acted like a charm on
female birds, in the same manner as changes of fashion
with us. The Duke of Argyll says M — and I am glad to
have the unusual satisfaction of following for even a short
distance in his footsteps — " I am more and more convinced
that variety, mere variety, must be admitted to be an ol>
ject and an aim in Nature." I wish the Duke had ex-
plained what he here means by Nature. Is it meant that
the Creator of the universe ordained diversified results for
His own satisfaction, or for that of man? The former no-
tion seems to me as much wanting in due reverence as the
latter in probability. Capriciousness of taste in the birds
themselves appears a more fitting explanation. For ex-
ample : the males of some parrots can hardly be said to
be more beautiful, at least according to our taste, than the
females, but they differ from them in such points as the
male having a rose-colored collar instead of, as in the fe-
male, " a bright emeraldinc narrow green collar ; " or in
the male having a black collar instead of " a yellow demi-
collar in front," with a pale roseate instead of a plum-bluo

■ 'The Journal of Travel,' edited by A. Murray, voL i. 1808, p. 286.

Chap. XVI.]

NOVELTY ADMIRED.

221

head.67 As so many male birds have for their chief orna-
ment elongated tail-feathers or elongated crests, the short-
ened tail, formerly described in the male of a humming-
bird, and the shortened crest of the male goosander almost
seem like one of the many opposite 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 coloring having apparently been
appreciated for the sake of novelty. The young of the
Ardea asha arc white, the adults being dark slate-colored ;
and not only the young, but the adults of the allied Buphus
coromandus in their winter plumage are white, this color
changing into a rich golden-buff during the breeding-sea-
son. It is incredible that the young of these two species,
as well as of some other members of the same family,68
should have been specially rendered pure white and thus
made conspicuous to their enemies ; or that the adults of
one of these two species should have been specially ren-
dered white during the winter in a country which is nc*cr
covered with snow. On the other hand, we have reason
to believe that whiteness lias been gained by many birds
as. a sexual ornament, We may therefore conclude that
an early progenitor of the Ardca asha and the JBtiphlM
acquired a white plumage for nuptial purposes, and trans-
mitted this color to their young; so that the young and
the old became white like certain existing egrets; the
whiteness having afterward been retained by the young
while exchanged by the adults for more strongly-pro-

" Reo .Icnlon on the genui PaltBOrnis, 'Birdl of India,' rol i. it-
UD8-200.

68 Tho young of Ardxi ru/rsrnis and A. arruha of tho United Statfj*
arc likewise whin-, tin- ndnlN heing colored in no 01 -dance with their spe-
clflc nuuiCH. Andulion ('Ornitli. 1 1 i* r:i i >h \ vol id. p, 416; fol it. p.
tiR) HccuiH rather |. leased ut (lie thought that thin rciiuii kuhlu change of
plumngO will great!) "di conceit the m\ Memati t -."

222

SEXUAL SELECTION: BIRDS.

[Part II.

nounced tints. But if we could look st ill farther back-
ward in time to the still earlier progenitors of these two
species, we should* probably see the adults dark-colored.
I infer that this would be the case, from the analogy of
many other birds, which are dark while young, and when
adult are white; and more especially from the case of the
Ardea gularis, the colors of which are the reverse of those
of A. asha, for the young are dark-colored and the adults
white, the young having retained a former state of plu-
mage. It appears, therefore, that the progenitors in their
adult condition of the Ardea as/ta, the ltitphi(s,.Mu\ of
some allies, have undergone, during a long line of descent,
the following changes of color: firstly a dark shade, sec-
ondly pure white, and thirdly, owing to another change
of fashion (if I may so express myself), their present slaty,
reddish, or golden-buff tints. These successive changes
are intelligible only on the principle of novelty having
been admired by birds for the sake of novelty.

Summary of the Four Chapters on Birds, — Most male
birds are highly pugnacious during the breeding-season,
and some possess weapons especially 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 6ong, or of emitting strange cries, or of pro-
ducing instrumental music, and the males in consequence
differ from the females in . their vocal organs, or in the
structure of certain feathers. From the curiously-dive rsi-
fied means for producing various sounds we gain a high
idea of the importance of this means of courtship. Many
birds endeavor to charm the females by love-dances or
antics, performed on the ground or in the air, and some-
times at prepared places. But ornaments of many kinds,

Chap. XVI.]

SUMMARY.

223

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 yi
fighting with their rivals. The males of very many spe-
cies do not assume their ornamental dress until they ar-
rive at maturity, or they assume it only during the breed-
ing-season, or the tints then become more vivid. Certain
ornamental appendages become enlarged, turgid, and
bright-colored, during the very act of courtship. The
males display their charms with elaborate care and to the
best effect ; and this is done in the presence of the females.
The courtship is sometimes a prolonged affair, and many
males and females congregate at an appointed place. To
suppose that the females do not appreciate the beauty of
the males is to admit that their splendid decorations, all
their pomp and display, are useless ; and this is incredible.
Birds have fine powers of discrimination, and in some few
instances it can be shown that they have a taste for the
beautiful. The females, moreover, arc known occasionally
to exhibit a marked preference or antipathy for certain in
dividual males.

If it be admitted that the females prefer, or are uncon
sciously 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 sc\
which lias been chiefly modified we may infer from the
fact that in almost every genus in which the sexes differ,
the malei differ much more from each other than do the
females; this is well shown in certain closely allied repre-
sentative species in which the females can hardly he dis-
tinguished, while the males are quite distinct. Ilinls in |

224

SEXUAL SELECTION: BIRDS.

[Taut II.

state of nature offer individual differences which^would
amply suffice for the work of sexual selection; hut we
have seen that they occasionally present more strongly-
marked variations, which recur so frequently that they
would immediately he fixed, if they served to allure the
female. The laws of variation will have determined the
nature of the initial changes, and largely influenced the
final result. The gradations, which may be observed be-
tween the males of allied species, indicate the nature of
the steps which have been passed through, and explain in
the most interesting manner certain characters, such as
the indented ocelli of the tail-feathers of the peacock, and
the wonderfully-shaded ocelli of the wing-feathers of the
Argus pheasant. It is evident that the brilliant colors,
top-knots, fine plumes, etc., of many male birds cannot
have been acquired as a protection ; indeed, they some-
times 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
.onditions acting during a lengthened period have pro-
duced some definite effect on both sexes, the more impor-
tant result will have been an increased tendency to fluc-
tuating variability or to augmented 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 ac-
quired by the males for the sake of ornament, for pro-
ducing 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 sometimes have
been transmitted in one way and sometimes in another is,

Chap. XVI.]

SUMMARY.

225

in most cases, not known ; but the period of variability
seems often to have been the determining cause. When
the two sexes have inherited all characters in common
they necessarily resemble each other; but, as the suc-
cessive variations may be differently transmitted, every
possible gradation may be found, even within the same
genus, from the closest similarity to the widest dissimi-
larity between the sexes. With many closely-allied spe-
cies, following nearly the same habits of life, the males
have' come to differ from each other chiefly through the
action of sexual selection ; while the females have come to
differ chiefly from partaking in a greater or lesser degree
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 case
of the males, by the accumulation through sexual selection
of strongly-pronounced colors and other ornaments. The
individuals of both sexes, however affected, will have been
kept at each successive period nearly uniform by the free
intercrossing of many individuals.

With the species, in which the sexes differ in color,
it is possible that at first there existed a tendency to
transmit the successive variations equally to both sexes ;
and that the females were prevented from acquiring the
bright colors of the males, on account of the danger to
which they would have been exposed during incubation.
But it would be, as far as I can see, an extremely difficult
process to convert, by means of natural selection, one form
of transmission into another. On the other hand, there
would not be the least difficulty in rendering a female
dull-colored, the male being still kept bright-colored, by
tin; 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 bhufl modi-
fied, must at present remain donbtful. W la n, through

220

SEXUAL SELECTION: BIRDS.

[Part II.

the law of the equal transmission of characters to both
sexes, the females have been rendered as conspicuously
colored as the males, their instincts have often been modi-
fied, and tliey have been led to build domed or concealed
nests.

*In one small and curious class of cases the characters
and habits .of the. two sexes have been completely trans-
posed, for the females are larger, stronger, more vociferous,
and brightly-colored than the males. They have, also,
become so quarrelsome that they often fight together like
the males of the most pugnacious species. If, as seems
probable, they habitually drive away rival females, and
by the display of their bright colors or other charms en-
deavor to attract the males, we can understand how it is
that they have gradually been rendered, by means of sex-
ual selection and sexually-limited transmission, more beau-
tiful than the males — the latter being left unmodified or
only slightly modified.

Whenever the law of inheritance at corresponding
ages prevails, but not that of sexually-limited transmission,
then if the parents vary late in life — and we know that
this constantly occurs with our poultry, and occasionally
with other birds — the young will be left unaffected, while
the adults of both sexes will be modified. If both these
laws of inheritance prevail and either sex varies late in
life, that sex alone will be modified, the other sex and the
young being left unaffected. When variations in bright-
ness or in other conspicuous characters occur early in life,
as no doubt often happens, they will not be acted on
through sexual selection until the period of reproduction
arrives ; consequently, if dangerous to the young, they
will be eliminated through natural selection. Thus we
can understand how it is that variations arising late in
life have so often been preserved for the ornamentation
of the males, the females and the young being left almost

Chm>. XVI.]

SUMMARY.

227

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 color 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 im-
mature plumage gives us an indirect record. Many birds,
especially those which live much on the ground, have un-
doubtedly been obscurely colored for the sake of protec-
tion. In some instances the upper exposed surface of the
plumage has been thus colored in both sexes, while the
lower surface in the males alone has been variously orna-
mented through sexual selection. Finally, from the facts
given in these four chapters, we may conclude that weap-
ons for battle, organs for producing sound, ornaments of
many kinds, bright and conspicuous colors, have gener-
ally been acquired by the males through variation and
sexual selection, and have been transmitted in various
ways according to the several laws of inheritance — the fe-
males and the young being left comparatively but little
modified.69

69 I am greatly indebted to the kindness of Mr. BolatOP for hiring
looked over these four chapters on birds, and the two following ones on
mammals. 1 ly this means I have been saved from making mi-takes id. out
the namefl of the species, and from giving any facts which are actually
known to this distinguished naturalist to be erroneous, Hut of OOQTM

he is not at ail answerable for the accuracy of the sUtexnenti quoted bj

me from various authorities.

Jv28

6EXUAL SELECTION: MAMMALS.

[Part IL

#-

CHAPTER XVII.

Secondary Sexual Characters op Mammals.

The Law of Battle. — Special "Weapons, confined to the Males. — Cause of
Absence of Weapons in the Female. — "Weapons common to both
Sexes, yet primarily acquired by the Male. — Other Uses of such Weap-
ons.— Their High Importance. — Greater Size of the Male. — Means of
Defence. — On the Preference shown by either Sex in the Pairing of
Quadrupeds.

With mammals the male appears to win the female
much more through the Ykw of battle than through the
display of his charms. The most timid animals, not pro-
vided with any special weapons for fighting, engage in
desperate conflicts during the season of love. Two male
hares have been seen to fight together until one was
killed ; male moles often fight, and sometimes with fatal
results ; male squirrels " engage in frequent contests, and
often wound each other severely ; " as do male beavers, so
that "hardly a skin is without scars."1 I observed the
same fact with the hides of the guanacoes in Patagonia;
and on one occasion several were so absorbed in fighting
that they fearlessly rushed close by me. Livingstone
speaks of the males of the many animals in Southern

1 Sec "Watcrton's account of two hares fighting, 4 Zoologist,' vol L
1843, p. 211. On moles, Bell, 'Hist, of British Quadrupeds,' 1st edit,
p. 100. On squirrels, Audubon and Bachman, ' Viviparous Quadrupeds
of North America,' 1846, p. 269. On beavers, Mr. A. U. Green, in 'Jour
nal of Lin. Soc. Zoolog.' vol. x. 1869, p. 362.

Chap. XVII.] LAW OF BATTLE.

229

Africa as almost invariably showing the scars received in
former contests.

The law of battle prevails with aquatic as with terres-
trial mammals. It is notorious how desperately male seals
fight, both with their teeth and claws, during the breed-
ing-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 it is believed by some naturalists that the frequently
deformed state of their lower jaws is caused by these
struggles.2

All male animals which are furnished with special
weapons for fighting, are well known to engage in fierce
battles. The courage and the desperate conflicts of stags
have often been described ; their skeletons have been
found in various parts of the world, with the horns inex-
tricably locked together, showing how miserably the vic-
tor and vanquished had perished.3 No animal in the
world is so dangerous as an elephant in must. Lord Tan-
kervillc has given me a graphic description of the battles
between the wild-bulls in Chillingham Park, the descend-
ants, degenerated in size but not in courage, of the gigan-
tic JBos primigcnius. In 18G1 several contended for mas-
tery; 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

3 On tho battles of seals, sec Captain C. Abbott in Troc. Zool. Soc.'
1868, p. 191; also Mr. II. Brown, ibid. 18G9, p. 4:50; also L. Lloyd,
4 (lame-Birds of Sweden,' 1867, p. 412; also Pennant On the sperm*
whale, sco Mr. J. II. Thompson, in 1 Proc. Zool. Soc' lSi'.T, p. - !•'>.

8 See Scropc('Art of Deer-stalking,' p. 17) on the locking of the
horns with the Cervus claphus. Richardson, in 1 Fauna llor. Amei icana,'
lH'it), p. 252, says thai Ihe wapiti, moose, and reindeer, have bcon found

thus looked together. Sir A Smith found at the Oape of Good Mope

the skeletons of two gnus in the sa condition.

230

SEXUAL SELECTION: MAMMALS. [Tart EL

to be lying mortally wounded in a neighboring wood.
But a few days afterward one of the young bulls singly
approached the wood; 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. lie
then quietly joined the herd, and long held undisputed
sway. Admiral Sir B. J. Sulivan informs me that when
he resided in the Falkland Islands he imported a young
English stallion, which, with eight mares, frequented the
hills near Port William. 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 captain who had charge of the
horses, and who, on riding to the spot, found one of the
two stallions engaged with the English horse, while the
other was driving away the mares, and had already sepa-
rated four from the rest. The captain settled the mattes
by driving the whole party into the corral, for the wild-
stallions would not leave the mares."

Male animals already provided with efficient cutting or
tearing teeth for the ordinary purposes of life, as in the
carnivora, insectivora, and rodents, are seldom furnished
with weapons especially adapted for fighting with their
rivals. The case is very different with the males of many
other animals. "We see this in the horns of stags and of
certain kinds of antelopes in which the females are horn-
less. With many animals the canine teeth in the upper
or lower jaw, or in both, arc much larger in the males
than in the females ; or are absent in the latter, with the
exception sometimes of a hidden rudiment. Certain ante-
lopes, the musk-deer, camel, horse, boar, various apes,
seals, and the walrus, offer instances of these several cases.

Chap. XVII.] LAW OF BATTLE.

231

In the females of the walrus the tusks are sometimes quite
absent.4 In the male elephant of India and in the male
dugong 6 the upper incisors form offensive weapons. In
the male narwhal one alone of the upper teeth is de-
veloped into the well-known, spirally-twisted, so-called
horn, which is sometimes from nine to ten feet in length.
It is believed that the males use these horns for fighting
together ; for " an unbroken one can rarely be got, and oc-
casionally one may be found with the point of another
jammed into the broken place." 8 The tooth on the oppo-
site side of the head in the male consists of a rudiment
about ten inches in length, which is embedded in the jaw.
It is not, however, very uncommon to find double-horned
male narwhals in which both teeth are well developed. In
the females both teeth are rudimentary. The male ca-
chalot has a larger head than that of the female, and it no
doubt aids these animals in their aquatic battles. Lastly,
the adult male ornithorhynchus is provided with a remark-
able apparatus, namely, a spur on the fore-leg, closely
resembling the poison-fang of a venomous snake; its use
is not known, but we may suspect that it serves as a
weapon of offence.7 It is represented by a mere rudiment
in the female.

When the males arc provided with weapons which the
females do not possess, there can hardly be a doubt that
they are used for fighting with other males, and that they
have been acquired through sexual selection. It is not
probable, at least in most cases, that the females have

4 Mr. Lamont ('Seasons with the Sca-IIorses,' 18fil, p. 11:!) says that
a good tuHk of the male walrus weighs lour pounds, and is longer than
that of the female, which weighs about three pounds. The male-- are
described as fighting ferociously. On the occasional absence of the tusks
In the female, fceo Mr. 1{. Hrown, ' ['rue. Zool. Soc.' ISCS, p. I."'.

B Ow«D, 'Anatomy of Vertebrates,' vol. iii. p. l!s:t.

* Mr. K. Brown, in ' Pro.-. Zool. Soc' INf.'.t, p. r.Mt.

1 Owen on the Oachalol and Ornithorhy&ohua, ibid rol UL pp. 668, 64 1

232

SEXUAL SELECTION: MAMMALS.

[Part II.

actually been saved from acquiring such weapons, owing
to their being useless and superfluous, or in some way in-
jurious. On the contrary, as they are often used by the
males of many animals for various purposes, more especially
as a defence against their enemies, it is a surprising fact
that they are so poorly developed or quite absent in the
females. No doubt with female deer the development
during each recurrent season of great branching horns,
and with female elephants the development of immense
tusks, would have been a great waste of vital power, on
the admission that they were of no use to the females.
Consequently variations in the size of these organs, lead-
ing to their suppression, would have come under the con-
trol of natural selection, and, if limited in their transmission
to the female offspring, would not have interfered with their
development through sexual selection in the males. But
how on this view can we explain the presence of horns in
the females of certain antelopes, and of tusks in the
females of many animals, which are only of slightly less
size than in the males ? The explanation in almost all
cases must, I believe, be sought in the laws of transmis-
sion.

As the reindeer is the single species in the whole fam-
ily of Deer in which the female is furnished with horns,
though somewhat smaller, thinner, and less branched than
in the male, it might naturally be thought that they must
be of some special use to her. There is, however, some
evidence opposed to this view. The female retains her
horns from the time when they are fully developed, namely,
in September, throughout the winter, until May, when she
brings forth her young ; while the male casts his horns
much earlier, toward the end of November. As both
sexes have the Bame requirements and follow the same
habits of life, and as the male sheds his horns during the
winter, it is very improbable that they can be of any spe-

Chap. XYII.]

LAW OF BATTLE.

233

cial service to the female at this season, which includes the
larger proportion of the time during which she bears
horns. JSTor is it probable that she can have inherited
horns from some ancient progenitor of the whole family
of deer, for, from the fact of the males alone of so many
species in all quarters of the globe possessing horns, we
may conclude that this was the primordial character of
the group. Hence it appears that horns must have been
transferred from the male to the female at a period sub-
sequent to the divergence of the various species from a
common stock ; but that this was not effected for the sake
of giving her any special advantage.8

We know that the horns are developed at a most un-
usually early age in the reindeer ; but what the cause of
this may have been is not known. The effect, however,
has apparently been the transference of the horns to both
sexes. It is intelligible, on the hypothesis of pangenesis,
that a very slight change in the constitution of the male,
either in the tissues of the forehead or in the gcmmules of
the horns, might lead to their early development ; and, as
the young of both sexes have nearly the same constitu-
tion before the period of reproduction, the horns, if devel-
oped at an early age in the male, would tend to be de-
veloped equally in both sexes. In support of this view,
we should bear in mind that the horns are always trans-
mitted through the female, and that she has a latent
capacity for their development, as we see in old or dis-
eased females.9 Moreover the females of some other

8 On tho Htructuro and shedding of the horns of the reindeer, Soft
bcrfj, 1 Amomitatei Acad.' vol. to, 1788, i>. 149. Sec EUohtrdeon, 'Fauna

Bor. Americana,' p. 'J 11, in regard to the American variety or species ;
alHO Major W. Ross King, 'The Sportsman in Canada,' 1 Still, p. SO.

'Isidore CJcoflYoy St.-IIilaire, • Kssais do Zoning, ticneralo,' ISM, p.
CI 3. Other masculine characters, besides the hone, are sometimes sim-
ilarly transferred to tho female; tlms Mr. I toner, in speaking of an old

234

SEXUAL SELECTION" : MAMMALS. [Part II.

species of deer, either normally or occasionally, exhibit
rudiments of bonis ; thus the female of Cervulus moscha-
tus has "bristly tufts, ending in a knob, instead of a horn ; "
and " in most specimens of the female Wapiti ( Ccrvus
Canadensis) there is a sharp bony protuberance in the
place of the horn." 10 From these several considerations
we may conclude that the possession of fairly well-
developed horns by the female reindeer, is due to the
males having first acquired them as weapons for fighting
with other males ; and, secondarily, to their development
from some unknown cause at an unusually early age in
the males, and their consequent transmission to both
sexes.

Turning to the sheath-horned ruminants: with ante-
lopes a graduated series can be formed, beginning with
the species, the females of which are completely destitute
of horns — passing to those which have horns so small ;is
to be almost rudimentary, as in Antilocapra Americana
— to those which have fairly well-developed horns, but
manifestly smaller and thinner than in the male, and
sometimes of a different shape,11 and ending with those in
which both sexes have horns of equal size. As with the
reindeer, so with antelopes, there exists a relation be-
tween 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

female chamois ('Chamois Hunting in the Mountains of Bavaria,' I860,
2d edit. p. 863), says, " not only was the head very male-looking, but along
the back there was a ridge of long hair, usually to be found only in
bucks."

10 On the Cervulus, Dr. Gray, ' Catalogue of the Mammalia in British
Museum,' part iii. p. 220. On the Cervus Canadensis or Wapiti see lion.
J. D. Caton, 'Ottawa Acad, of Nat. Sciences,' May, 1868, p. 9.

11 For instance, the horns of the female Ant. Euchore resemble those
of a distinct species, viz. the Ant. Dorcas var. Corine, see Dcsmarcst,
' Mammalogie,' p. 455.

Chap. XVII.] LAW OF BATTLE.

235

some species, and their more or less perfect condition in
the females of other species, depend, not • on their being
of some special use, but simply on the form of inheritance
which has prevailed. It accords with this view that even
in the same restricted genus both sexes of some species,
and the males alone of other species, are thus provided.
It is a remarkable fact that, although the females of Anti-
lope bezoartica are normally destitute of horns, Mr. Blyth
lias seen no less than three females thus furnished ; and
there was no reason to suppose that they were old or dis-
eased. The males of this species have long, straight,
spirated horns, nearly parallel to each other, and directed
backward. Those of the female, when present, are very
different in shape, for they are not spirated, and, spread-
ing widely, bend round, so that their points are directed
forward. It is a still more 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. In all cases the differences between the horns of
the males and females, and of castrated and entire males,
probably depend on various causes— on the more or less
complete transference of male characters to the females —
on the former state of the progenitors of the species — and
partly, perhaps, on the horns being differently nourished,
in nearly the same manner as the spurs of the domestic.
OOOk, when inserted into the comb or other parti of the
body, assume various abnormal forms from being differ-
cut ly nourished.

In all the wild species of goats and sheep the horns :nv
larger in the male than in the female, and are sometime!
quite absent in the latter." In several domestic breeds
of the sheep and goat, the males alone are famished with
horns; and it is a significant fact that, in one such breed
of sheep on the(iuinea coast, the horns are nol devel-
11 Gray, 1 Cutiilogur Minimi. Ilrit. Mus.' pint iii. IS.VJ, |>. ItiO.

23G SEXUAL SELECTION: MAMMALS. [Part II.

oped, as Mr. Winwood Reade informs me, in the castrated
male ; so that they are affected in this respect like^he liorns
of stags. In some breeds, as in that of North Wales,
in which both sexes are properly horned, the ewes are
very liable to be hornless. In these same sheep, as I have
been informed by a trustworthy witness who purposely
inspected a flock during the lambing-season, the horns at
birth are generally more fully developed in the male than
in the female. With the adult musk-ox (Ovibos moscha-
tus) the horns of the male are larger than, those of the
female, and in the latter the bases do not touch.1' In re-
gard 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-ban-
teng (Bos sondaicus) the horns are remarkably small,
and inclined much backward. In the domestic races of
cattle, both of the humped and humpless types, the horns
are short and thick in the bull, longer and more slender
in the cow and ox ; and in the Indian buffalo they are
shorter and thicker in the bull, longer and more slender
in the cow. In the wild-gaour (B. gaurus) the liorns are
mostly both longer and thicker in the bull than in the
cow."14 Hence with most sheath-horned ruminants the
horns of the male are either longer or stronger than those
of the female. With the Rhinoceros simus, as I may here
add, the horns of the female arc generally longer but less
powerful than in the male; and in some other species of
rhinoceros they are said to be shorter in the female.16
From these various facts we may conclude that horns of
all kinds, even when equally developed in both sexes,
were primarily acquired by the males in order to conquer

" Richardson, * Fauna Bor. Americana,' p. 278.
u ' Land and water,' 1867, p. 846.

15 Sir Andrew Smith, 4 Zoology of South Africa,' pL xix. Owen, 1 Anat»
omy of Vertebrates,' vol. iii. p. 624.

Chap. XVIL]

LAW OF BATTLE,
f

237

other males, and have been transferred more or less com-
pletely to the female, in relation to the force of the equal
form of inheritance.

The tusks of the elephant, in the different species or
races, differ according to sex, in nearly the same manner
as the horns of ruminants. In India and Malacca the
males alone are provided with well-developed tusks. The
elephant of Ceylon is considered by most naturalists as a
distinct race, but by some as a distinct species, and here
" not one in a hundred is found with tusks, the few that
possess them being exclusively males." 10 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 Antilopc bezo-
artica — the presence of two tusks in some few male nar-
whals— the complete absence of tusks in some female
walruses — are all instances of the extreme variability of
secondary sexual characters, and of their extreme liability
to differ in closely-allied forms.

Although tusks and horns appear in all cases to have
been primarily developed as sexual weapons, they often
serve for other purposes. The elephant uses his tusks in
attacking the tiger; according to Bruce, he scores the
trunks of trees until they can be easily thrown down, and
lie likewise thus extracts the farinaceous cores of palms ■
in Africa he often uses one tusk, this being always the
same, to probe the ground and thus to 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

19 Sir J. KiiHTHon Ti'imont, ' (Vylon,' Is:.'.), vol. ii. |>. 'JVt. For Mn-
lacca, 'Journal oflndUn Archipelago,' vol. iv. |».

238 SEXUAL SELECTION: MAMMALS. [Part II.

single blow of his great horns. Many similar facts could
be given. One of the most curious secondary uses to
which the horns of any animal are occasionally put, is
that observed by Captain Hutton,17 with the wild-goat
(Capra (rgagrus) of the Himalayas, and, as it is said,
with the ibex, namely, that when the male accidentally
falls from a height, he bends inward 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 so much
need this strange kind of shield.

Each male animal uses his weapons in his own pecu
liar fashion. The common ram makes a charge and butts
with such force with the bases of his horns, that I have
seen a powerful man knocked over as easily as a child.
Goats and certain species of sheep, for instance the Ovis
cycloceros of Afghanistan,18 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. cycloceros attacked a large
domestic ram, who was a noted bruiser, he conquered him
by the sheer novelty of his mode of lighting, always clos-
ing at once with his adversary, and catching him across
the face and nose with a sharp drawing jerk of his 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 other 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

« 'Calcutta Journal of Nat. Hist.' vol iL 1843, p. 526.

18 Mr. Blyth, in 'Land and Water,' March, 1867, p. 134, on the au-
thority of Captain Hutton and others. For the wild Pembrokeshire
goats see the 'Field,' 1869, p. 150.

Chap. XVII.]

LA.W OF BATTLE.

239

opponent ; but the Italian buffalo is said never to use his
horns, he gives a tremendous blow with his convex fore-
head, and then tramples on his fallen enemy with his
knees — an instinct which the common bull does not pos-
sess.19 . Hence a dog who pins a buffalo by the nose is im-
mediately crushed. We must, however, remember that
the Italian buffalo has long been domesticated, and it is
by no means certain that the wild parent-form had simi-
larly shaped horns. Mr. Bartlett informs me that when
a female Cape buffalo (JBubalus Coffer) was turned into an
enclosure with a bull of the same species, she attacked
him, and he in return pushed her about with great vio-
lence. But it was manifest to Mr. Bartlett that had not
the bull shown dignified forbearance, he could easily have
killed her by a single lateral thrust with his immense
horns. The giraffe uses his short, hair-covered horns,
which are rather longer in the male than in the female, in
a curious manner ; for with his long neck he swings his
head to either side, almost upside down, with such force,
that I have seen a hard plank deeply indented by a single
blow.

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 up-
right horns, with the sharp points bent inward almost at
a right angle, so as to face each oilier; Mr. Bartlett does
not know how they are used, but suggests that they
woHld inflict a fearful wound down each side of the lace
of an antagonist. The slightly-curved horns of the Oryx
leucoryx (Fig. 01) are directed backward, and are of such
length that their points reach beyond the middle of the
back, over which they stand in an almost parallel line.
Thus they seem singularly ill-lit t cd for lighting; hut Mr.

11 M. K. M. Ilaill y, "Stir l'tisa^c den Conies," rti\, 'Annul, lies Se.
Nut.' torn. ii. 1824, p. 869,

240

SEXUAL SELECTION : MAMMALS. (Taut II.

Bartlett informs mc that when two of these animals pre-
pare for battle, they kneel down, with their heads between
their front legs, and in this attitude the horns stand near-
ly parallel and close to the ground, with the points di-
rected forward and a little upward. . The combatants
then gradually approach each other and endeavor to get
the upturned points under each other's bodies ; if one suc-
ceeds in doing this he suddenly springs up, throwing up

Fia. 61.— Oryx leucoiyx, male (from the Knowsley Menagerie).

his head at the same time, and can thus wound or per-
haps even transfix his antagonist. Both animals always
kneel down so as to guard as far as possible against this
manoeuvre. It has been recorded that one of these ante-
lopes 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 the horns forward, he
would generally be under a great disadvantage when at-
tacked by any other animal.. It is, therefore, not probable
that the horns have been modified into their present great
length and peculiar position, as a protection against
beasts of prey. We can, however, see that as soon as

Chap. XVII.]

LAW OF BATTLE.

241

some ancient male progenitor of the Oryx acquired mod-
erately long horns, directed a little backward, he would
be compelled in his battles with rival males to bend his
head somewhat inward or downward, as is now done by
certain stags ; and it is not improbable that he might
have acquired the habit of at first occasionally and after-
ward of regularly kneeling down. In this case it is al-
most 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 branching of the horns
offers a curious case of difficulty ; for certainly a single
straight point would inflict a much more serious wound
than several diverging points. In Sir Philip Egerton's
museum there is a horn of the red-deer (Cervus ela-
phus) 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 L, each of which bears the aston-
ishing number of thirty-three branches. Richardson
figures a pair of antlers of the wild-reindeer with twenty-
nine points.20 From the manner in which the horiiH
are branched, and more especially from deer being
known occasionally to light together by kicking with
their forefeet," M. Bailly actually came to the con-

50 Owen, on the Horns of Rod-deer, 'British Fossil Mammals,' I s i r,,
p. 47H; 'Forest Creatures,' by Charles Bontr, 1801, pp. 02, 7<>. Kich-
ardson on the Horns of the Reindeer, 'Fauna Bor. Americana,' 1889,
p. 240.

,l Hon. J. I). Caton ('Ottawa Acad, of Nat. Science,' May, IKI'.H, p. Jl^
Bays that the American deer li^lit with their forefeet, after " the IglMI
lion of superiority has been once settled and acknowledged in the herd '«

:{()

2\->

SEXUAL SELECTION: MAMMALS. [Part II.

elusion that their horns were more injurious than useful
to them ! Hut this author overlooks t lie pitched battles
between rival males. As I felt much perplexed about
the use or advantage of the branches, I applied to Mr.
McNeill of Colinsay, 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 action, but that
the brow-antlers, from inclining downward, are a great
protection to the forehead, and their points are likewise
used in attack. Sir Philip Egerton also informs me, in
regard both to red-deer and fallow-deer, that when they
fight they suddenly dash together, and getting their horns
fixed against each other's bodies a desperate struggle
ensues. When one is at last forced to yield and turn
round, the victor endeavors 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, with some species the Upper
branches are used as weapons of offence ; when a man
was attacked by a Wapiti deer ( Cervus Canadensis) in
Judge Caton's park in Ottawa, and several men tried to
rescue him, the stag " never raised his head from the
ground ; in fact he kept his face almost flat on the ground,
with his nose nearly between his forefeet, except when he
rolled his head to one side to take a new observation pre-
paratory to a plunge." In this position the terminal points
of the horns were directed against his adversaries. " In
rolling his head he necessarily raised it somewhat, because
his antlers were so long that he could not roll his head
without raising them on one side, while on the other side
they touched the ground." The stag by this procedure
gradually drove the party of rescuers backward, to a

Bailly, " Sur l'usage des Cornea," 4 Annates des Sc. Nat' torn, il 1824,
p. 871.

Chap. XVII.]

LAW OF BATTLE.

243

distance of 150 or 200 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 much more dangerous than a branched antler ; and
Judge Caton, who has had large experience with deer,
fully concurs in this conclusion. g 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 partly as ornaments. That the branched antlers of
stags, as well as the elegant lyrated horns of certain ante-
lopes, with their graceful double curvature (Fig. 62), 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 partly modified for this purpose, though
mainly for actual service in battle ; but I have no evidence
in favor of this belief.

An interesting case has lately been published, from
which it appears that the horns of a deer in one district
in the United States are now being modified through
sexual and natural selection. A writer in an excellent
American journal" says that he has hunted for the last
twenty-one years in the Adirondack*, where the Cervus
Virginianua abounds. About fourteen years ago he fu st
heard of spike-hnm bucks. These became from year to
year more common ; about five; years ago he shot one, and
subsequently another, and now they are frequently killed.
"The spike-horn diHers greatly from the common antler
of the C. Virginia mis. It consists of a single spike, more

»• Roo a moMt intcrcHt'm^ account in the Appendix t«> lion, J, 1».
Calon'n paper, ii s nttovo quoted.

M The American Nntunil'iHt,' Dec. l«tU», p. f.f.'J.

244 SEXUAL SELECTION: MAlflfAm, |pAttT n-

slender than the antler, and scarcely half 80 long, project-
ing forward from the brow, and terminating in a very

Pio. 62.— Stropsiceros Kndu (from Andrew Smith's 'Zoolopy of South Africa')

sharp point. It gives a considerable advantage to its
possessor over the common buck. Besides enabling him
to run more swiftly through the thick woods and under-

Chap. XVII.]

LAW OF BATTLE.

245

brush (every hunter knows that does and yearling bucks
run much more rapidly than the large bucks when armed
with their cumbrous antlers), the spike-horn is a more
effective weapon than the common antler. With this
advantage the spike-horn bucks are gaining upon the
common bucks, and may, in time, entirely supersede them
in the Adirondacks. Undoubtedly the first spike-horn
buck was merely an accidental freak of Nature. But his
spike-horns gave him an advantage, and enabled him to
propagate his peculiarity.- His descendants, having a like
advantage, have propagated the peculiarity in a constantly
increasing ratio, till they are slowly crowding the antlered
deer from the region they inhabit."

Male quadrupeds which are furnished with tusks use
them in various ways, as in the case of horns. The boar
strikes laterally and upward ; the musk-deer with serious
effect downward.34 The walrus, though having so short a
neck and so unwieldy a body, "can strike either upward,
or downward, or sideways, with equal dexterity."" The
Indian elephant fights, as I was informed by the late Dr.
Falconer, in a different manner according to the position
and curvature of his tusks. When they are directed for-
ward and upward he is able to fling a tiger to a great dis-
tance— it is said to even thirty feet ; when they are short
and turned downward he endeavors suddenly to pill the
tiger to the ground, and inconsequence is dangerous to
the rider, who is liable to be jerked oil* tin- hoodah.39

Very few male quadrupeds possess weapons of two
distinct kinds specially adapted for lighting with rival
males. The male muntjae-deer (( '< rntt/i/s), however,

'H Pafltf, 1 Sploflegi* Zoologtoa,' duo. xiii. 177'.', p. is.

Liimont, 1 Seasons with tin- Sni iloi . ,' ISi',1, p. I t I.
"•See also (\n>e (' I'hilosoph. Transaet.' IV'.''.', p. '.'I'.!) <>n the manner
in which the short-tusked Mooknah variety nf tin- < •!• pliant at t n«-k ^ other
elephant h.

246

SEXUAL SELECTION: MAMMALS. [Part II.

offers an exception, as he is provided with horns and ex-
serted canine teeth. But one form of weapon has often
been replaced in the course of ages by another form, as
we may infer from what follows. With ruminants the
development of horns generally stands in an inverse rela-
tion with that of even moderately well-developed canine
teeth. Thus camels, guanacoes, chevrotains, and musk-
deer, are hornless, and they have efficient canines ; these
teeth being "always of smaller size in the females than in
the males." The Camelidoe have in their upper jaws, in
addition to their true canines, a pair of canine-shaped in-
cisors." Male deer and antelopes, on the other hand, pos-
sess 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.
With 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 deer have been known occa-
sionally to exhibit rudiments of these teeth.38 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 widely like camels and guana-
coes. Whenever the adult male possesses canines now in
an inefficient state, while 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,

»7 Owen, ' Anatomy of Vertebrates,' vol. iii. p. 849.

MSec RUppell (in * Proc. Zoolog. Soc.' Jan. 12, 1836, p. 3) pn the
canines in deer and antelopes, with a note by Mr. Martin on a female
American deer. See also Falconer (' Palseont. Memoirs and Notes,' voL
i. 1868, p. 576) on canines in an adult female deer. In old males of the
musk,deer the canines (Pallas, 4 Spic. Zoolog.' fasc. iiii. 1779, p. 18)
sometimes grow to the length of three inches, while in old females a ru-
diment projects scarcely half an inch above the gums.

Chap. XVII ]

LAW OF BATTLE.

247

which had been partially transferred to the females. The
reduction of these teeth in the males seems to have fol-
lowed from some change in their manner of fighting, often
caused (but not in the case of the horse) by the develop-
ment of new weapons.

Tusks and horns are manifestly of high importance to
their possessors, for their development consumes much
organized matter. A single tusk of the Asiatic elephant
— one of the extinct woolly species — and of the African
elephant, have been known to weigh respectively 150, 160,
and 180 pounds; and even greater weights have been as-
signed by some authors." With deer, in which the horns
are periodically renewed, the drain on the constitution
must be greater ; the horns, for instance, of the moose
weigh from fifty to sixty pounds, and those of the extinct
Irish elk from sixty to seventy pounds — the skull of the
latter weighing on an average only five and a quarter
pounds. With sheep, although the horns are not periodi-
cally renewed, 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 arc
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 dead twig when walking
quietly, cannot act so dexterously while 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.'" nu The

19 Emerson Tennent, 'Ceylon,' 1S.V.», vol. ii. p. '2 7 r. ; Owen, ' Hritish

Fossil Mammals,' 1846, i>. 245.

80 Richardson, 4 Fauna Itor. Americana,' on the moose, A!<rs /mlmata,
p iiflfl, 2.S7 ; also, on the expanse of the horns, 1 I. ami ami Water,' lsr.-.t,
p. Hit. See also Owen, ' Hritish Fossil Mammals' 00 tht Iri-h elk, pp.
4 17, 155.

248

SEXUAL SELECTION: MAMMALS. [Part II.

tips of the horns of the great Irish elk were actually
eight feet apart ! While the horns are covered with
velvet, which lasts with the red-deer for. about twelve
weeks, they are extremely sensitive to a blow ; so that in
Germany the stags at this time change their habits to a
certain extent, and avoid dense forests, frequenting young
woods and low thickets.81 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 quadrupeds, when, as is often the case, the sexes
differ in size, the males are, I believe, always larger and
stronger. This holds good in a marked manner, as I am
informed by Mr. Gould, 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 (GaUorhinus ursinus), a full-
grown female weighing less than one-sixth of a full-grown
male." The greater strength of the male is invariably
displayed, as Hunter long ago remarked,93 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 pugna-
cious than the females. There can be little doubt that
these characters have been gained, partly through sexual
selection, owing to a long series of victories by the
stronger and more courageous males over the weaker, and '
partly through the inherited effects of use. It is probable
that the successive variations in strength, size, and cour-
age, whether due to so-called spontaneous variability or
to the effects of use, by the accumulation of which, male

31 'Forest Creatures,' by C. Boner, 1861, p. 60.

35 See the very interesting paper by Mr. J. A Allen in 1 Bull. Mus.
Comp. Zoolog. of Cambridge, United States,' vol. ii. No. 1, p 82. The
weights were ascertained by a careful observer, Captain Bryant

33 'Animal Economy,' p. 45.

Chap. XVII.] GREATER SIZE OF THE MALE.

249

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.

Under this point of view I was anxious to obtain in-
formation in regard to the Scotch deer-hound, the sexes
of which differ more in size than those of any other
breed (though blood-hounds differ considerably), or than
in any wild canine species known to me. Accordingly, I
applied to Mr. Cupples, a well-known breeder of these
dogs, who has weighed and measured many of his own
dogs, and who, with great kindness, has collected for me
the following facts from various sources. Superior male
dogs, measured at the shoulder, range from twenty-eight
inches, which is low, to thirty-three or even thirty-four
inches in height; and in weight from eighty pounds,
which is low, to one hundred and twenty, or even more
pounds. The females range in height from twenty-three
to twenty-seven or even twenty-eight inches; and in
weight from fifty to seventy, or even eighty pounds."
Mr. Cupples concludes that from ninety-five to one hun-
dred pounds for the male, and seventy 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
flff 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

84 Sec also Richardson's ' Manual on the Dog,' p. 59. Much valuahle
information on the Scottish deer-hound is given by Mr. McNeill, who
first called attention to the inequality in size hetween (lie sexes, in
Si-rope's * Art of Deer Stalking.' I hope thai Mr. Cupplei wiH keep to

his intention of publishing a lull account ami hlstorj of this famous

breed.

250

SEXUAL SELECTION: MAMMALS. [Part IT.

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 ex-
perience 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 sev-
eral weeks afterward, a bitch-puppy will occasionally be
larger than any of the dogs, but they are invariably
beaten by them later." Mr. McNeill, of Colinsay, con-
cludes that " the males do not attain their full growth till
over two years old, though the females attain it sooner."
According to Mr. Cupples's experience, male dogs go on
growing in stature till they are from twelve to eighteen
months old, and in weight till from eighteen to twenty-
four months old ; while the females cease increasing in
stature at the age of from nine to fourteen or fifteen
months, and in weight at the age of from twelve to fifteen
months. From these various statements it is clear that
the full difference in size between the male and female
Scotch deer-hound is not acquired until rather late in life.
The males are almost exclusively 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, courage, and the best will
have been bred from. As, however, the males do not
attain their full dimensions until a rather late period in
life, they will have tended, in accordance with the law
often indicated, to transmit their characters to their male

Chap. XVII.]

MEANS OF DEFENCE.

251

offspring alone ; and thus the great inequality in size be-
tween the sexes of the Scotch deer-hound may probably
be accounted for.

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 ex-
clusively for defending themselves ; and the Oryx ante-
lope, as I am informed by Mr. Bartlett, fences most skil-
fully with his long, gently-curved horns ; but these are
likewise used as organs of offence. Rhinoceroses, as the
same observer remarks, in fighting parry each other's side-
long blows with their horns, which loudly clatter together,
as do the tusks of
boars. Although wild-
boars fight desperate-
ly together, they sel- '
dom, according to
Brehm, receive fatal
blows, as these fall on
each other's tusks, or
on the layer of gristly
skin covering the shoul-
der, which the German

hunters Call the Shield ; Fig. 63.— ITead of common-wild boar, in
_ . . prime of life (from Brehm).

and here we have a

part specially modified for defence. With boars in the
prime of life (see Fig. 63) the tusks in the lower jaw
are used for fighting, but they become in old age, as
I5rchm states, so much curved inward and upward, over
the snont, that they can no longer be thus used. They
may, however, si ill continue to serve, and even in a still
more effective manner, as a means of defence. In com-
pensation for the loss of the lower tnsksas weapons of
offence, those in the nppcr jaw, which always project a

252 SEXUAL SELECTION: MAMifAiii [Pabt II.

little laterally, increase so much in length during old age
and curve so much upward, that they can be used as a
means of attack. Nevertheless an old boar is not so dan-
gerous to man as one at the age of six or seven years,"

In the full-grown male Babirusa pig of Celebes (Pig.
04), the lower tusks are formidable weapons, like thu.se of

o. . Sknll of tho Bablnina P\s (from Wallace** 1 Malay Archipelago ').

the European boar in the prime of life, while the upper
tusks are so long and have their points so much curled
inward, sometimes even touching the forehead, that they
are utterly useless as weapons of attack. They more near-
ly resemble horns than teeth, and are so manifestly useless
as teeth that the animal was formerly supposed to rest
Ins head by hooking them on to a branch. Their convex
K Brchm, 1 Thierkhcn,' It. \\. „. 729, 732.

Chap. XVII.] MEANS OF DEFENCE.

253

surfaces would, however, if the head were held a little
laterally, serve as an excellent guard; and hence, per-
haps, it is that in old animals they " are generally broken
off, as if by lighting." 36 Here, then, we have the curious
case of the upper tusks of the Babirusa regularly assum-
ing, during the prime of life, a structure which apparently
renders them fitted only for defence ; while in the Euro-
pean boar the lower and opposite tusks assume in a less
degree and only during old age nearly the same form, and
then serve in like manner solely for defence.

ii iwi i run i inn oravi uw (wrowuw ui

mi ii redtK '-d nciile. the chiiructi iH ol tin- mule i

Iii the wart-hog (P/ntcnr/iocrus a-thhtpirus, Kig.
the tusks in the upper jaw of the male ourve upward dur-
ing the prime of life, and, from being pointed, serve ai for
midahlc weapons. The tusk- in the lower ja* sre sharper
ihan thorn- in the upper, hut from their Bhortnesi it leemi
hardly possible thai they can be a Bed as weapons of at
tack. They must, however, greatly itrengthen those in the

■• Soe Mr. Wallace'* Intcrontlng account of thlft animal, 1 Thi Kslsj
Archipelago,' 1800, vol. I. p. 135.

254

SEXUAL SELECTION: MAMMALS. [Part II.

upper jaw, from being ground so as to fit closely against
their bases. Neither the upper nor the lower tusks ap-
pear to have been specially modified to act as guards,
though, no doubt, they are thus used to a certain extent.
But the wart-hog is not destitute of other special means
of protection, for there exists, on each side of the face, be-
neath the eyes, a rather stiff, yet flexible, cartilaginous,
obloug pad (Fig. 65), which projects two or three inches
outward; 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 upward, and would thus protect in an admira-
ble manner the somewhat prominent eyes. These boars,
as I may add on the authority of Mr. Bartlett, when fight-
ing together, stand directly face to face.

Lastly, the African river-hog (Potamochoerus penicil-
latus) has a hard cartilaginous knob on each side of the
face beneath the eyes, which answers to the flexible pad
of the wart-hog ; it has also two bony prominences on the
upper jaw above- the nostrils. A boar of this species in
the Zoological Gardens recently broke into the cage of
the wart-hog. They fought all night-long, and were
found in the morning much exhausted, but not seriously
wounded. It is a significant fact, as showing the purpose
of the above-described projections and excrescences, that
these were covered with blood, and were scored and
abraded in an extraordinary manner.

The mane of the lion forms a good defence against the
one danger to which he is liable, namely, the attacks of
rival lions : for the males, as Sir. A. Smith informs me,
engage in terrible battles, and a young lion dares not ap-
proach 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 in-
jured, but the tiger at last succeeded in ripping up his

Chap. XVII.]

MEANS OF DEFENCE.

255

belly, and in a few minutes he was dead." 37 The broad
ruff round the throat and chin of the Canadian lynx (Felis
Canadensis) is much longer in the male than in the fe-
male ; but whether it serves as a defence I do not know.
Male seals are well known to fight desperately together,
and the males of certain kinds (Otaria jubata)S6 have
great manes, while the females have small ones or none.
The male baboon of the Cape of Good Hope ( Cynocepha-
lus porcarius) has a much longer mane and larger canine
teeth than the female ; and the mane probably serves as a
protection, for on asking the keepers in the Zoological
Gardens, without giving them any clew 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, excepting with the above baboon. In
the Hamadryas baboon, Ehrenberg compares the mane of
the adult male to that of a young lion, while 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 any thing which favored
this belief. The stallion has a thicker and fuller mane than
the mare; and I have made particular inquiries of two
great trainers and breeders who have had charge of many
entire horses, and am assured that they "invariably en-
deavor to seize one another by the neck." It does not,
however, follow from the foregoing statements, (hat when

81 'The Times,' Nov. 10, 1857. In regard to (lie Canada lynx, sec

Audubon and BAohman, 'Quadruped! of North America,' 1846, p. 189.

,e Dr. Muric, on Otaria, ' IVoc. ZOOlog. BOO.' 1869, p. 100. Mr. J. A.
Allen, in the paper above quoted (p. 7r»), doubtH whether the hair, which
iH longer on the neck ill the male than in the female, deserves to he culled
u inline.

SKXUAL SELECTION: MAMMALS.

[Part II.

the hair on the neck serves as a defence, that it was origi-
nally developed for this purpose, though this is probable
in some cases, as in that of the lion. I am informed by
Mr. McNeill that the long hairs on the throat of the stag
( Cervus elephas) serve as a great protection to him when
hunted, for the dogs generally endeavor to seize him by
the throat ; but it is not probable that these hairs were spe-
cially developed for this purpose; otherwise the young
and the females would, as we may feel assured, have been
equally protected.

On Preference or Choice in Pairing, as shown by either
Sex of Quadrupeds. — Before describing, in the next chap-
ter, the differences between the sexes in voice, odor emit-
ted, and ornamentation, it will be convenient here to con-
sider whether the sexes exert any choice in their unions.
Does the female prefer any particular male, either before
or after the males may have fought together for supremacy ;
or does the male, when not a polygamist, select any par-
ticular female ? The general impression among breeders
seems to be that the. male accepts any female; and this,
owing to his eagerness, is in most cases probably the truth.
Whether the female as a general rule indifferently accepts
any male is much more doubtful. In the fourteenth chap-
ter, on Birds, a considerable body of direct and indirect
evidence was advanced, showing that the female selects
her partner ; and it would be a strange anomaly if female
quadrupeds, which stand higher in the scale of organiza-
tion 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, as so incessantly occurs,
by several males, she would often have the opportunity,
while they were fighting together, of escaping with, or at
least of temporarily pairing with, some one male. This

Chap. XVII.]

PREFERENCES IN PAIRING.

257

latter contingency has often been observed in Scotland
with female red-deer, as I have been informed by Sir Philip
Egerton.89

It is scarcely possible that much should be known
about female quadrupeds exerting in a state of nature any
choice in their marriage unions. The following very cu-
rious details on the courtship of one of the eared seals
Callorhinus ursinus, are given 40 on the authority of Cap-
tain Bryant, who had ample opportunities for observation.
He says : " Many of the females on their arrival at the isl-
and where they breed appear desirous of returning to some
particular male, and frequently climb the outlying rocks to
overlook the rookeries, calling out and listening as if for a
familiar voice. Then, changing to another place, they do
the same again .... As soon as a female reaches the shore,
the nearest male goes down to meet her, making mean-
while 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 man-
ner 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 neighbors are off their
guard to steal their wives. This they do by taking them
in their mouths and lifting them over the heads of the
other females, and carefully placing them in their own
harem, carrying them as cats do their kittens. Those still
higher up pursue the same method until the whole space

29 Mr. Boner in his excellent description of the habits of the red-deer
in (iermanyC Kore-t Creatures,1 L861, p. 81) fays, "While the stag is de-
fending his rights a^ain-t one inttiidcr, another invades the snnctUWfJ of

his harem, and oarriet offtroph) after trophy." Exactly the same tiling

occurs with seal-, -•■<• Mi. J. A. Allen, ibid. p. LOO.

40 Mr. J, A. Alien i,, ' Bull. Ifus, Oomp. Zoolog. of Cambridge, [Inked

Stales' vol. ii. No. I, p. W.

258

SEXUAL SELECTION: MAMMALS. [Part II.

is occupied Frequently a struggle ensues between the
two males for the possession of the same female, and both
seizing her at once pull her in two or terribly lacerate her
with their teeth. When the space is all filled, the old
male walks around complacently reviewing his family,
scolding those who crowd or disturb the others, and fierce-
ly driving off all intruders. This surveillance always
keeps him actively occupied."

As so little is known about the courtship of animals in
a state of nature, I have endeavored to discover how far
our domesticated quadrupeds evince any choice in their
unions. Dogs offer the best opportunity for observation,
as they are carefully attended to and well understood.
Many breeders have expressed a strong opinion on this
head. Thus Mr. Mayhew remarks, " The females are able
to bestow their affections ; and tender recollections are as
potent over them as they are known to be in other cases,
where higher animals are concerned. Bitches are not
always prudent in their loves, but are apt to fling them-
selves away on curs of low degree. If reared with a
companion of vulgar appearance, there often springs up
between the pair a devotion which no time can afterward
subdue. The passion, for such it really is, becomes of a
more than romantic endurance." Mr. Mayhew, who at-
tended chiefly to the smaller breeds, is convinced that the
females are strongly attracted by males of large size.41 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
similar and trustworthy accounts have been given me in

41 «Dogs: their Management/ by E. Mayhew, M. R. C. V. S., 2d edit.
1864, pp. 187-192.

4i Quoted by Alex. Walker 'On Intermarriage,' 1888, p. 276; see also
p. 244.

Chap. XVII.] PREFERENCES IN PAIRING.

259

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 neighbor, to such
degree that she had often to be dragged away from him.
After their permanent separation, although repeatedly
t ho wing milk in her teats, she would never acknowledge
she courtship of any other dog, and, to the regret of her
owner, never bore puppies. Mr. Cupples also states that
a female deer-hound now (1868) in his kennel has thrice
produced puppies, and on each occasion showed a marked
preference for one of the largest and handsomest, but not
the most eager, of four deer-hounds living with her, all in
the prime of life. Mr. Cupples has observed that the fe-
male generally favors 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 toward 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, in-
forms me that he has known some instances ; he cites the
case of one of his own deer-hounds, who would not take
any notice of a particular female mastiff, so that another
deer-hound had to be employed. It would be superlluous
to give other cases, and I will only add that Mr. Burr,
who has carefully bred many blood-hounds, states that in
almost every instance particular individuals of the oppo-
site sex show a decided preference for each other. Finally
Mr. Cupples, after attending to this subject for another
year, has recent ly written tome: "I have had lull con-
firmation of my former statements, that dogs in breeding
form decided preference! for each other, being often in-
fluenced by size, brighl color, and individual character, as
Well as by the degree of their previous familiaril y

200

SEXUAL SELECTION: MAMMALS. [Part II.

In regard to horses, Mr. Blenkiron, the greatest breed-
er of race-horses in the world, informs me that stallions
are so frequently capricious in their choice, rejecting one
mare and without any apparent cause taking to another,
that various artifices have to be habitually used. The fa-
mous Monarque, for instance, would never consciously
look at the dam of Gladiateur, and a trick had to be prac-
tised. We can partly see the reason why valuable race
horse stallions, which are in such demand, should be so
particular in their choice. Mr. Blenkiron has never known
a mare to reject a horse ; but this has occurred in Mr.
Wright's stable, so that the mare had to be cheated.
Prosper Lucas 43 quotes various statements from French
authorities, and remarks, " On voit des etalons qui s'6-
prennent d'une jument, et negligent toutes les autres."
He gives, on the authority of Baelen, similar facts in re-
gard to bulls. Hoffberg, in describing the domesticated
reindeer of Lapland, says, " Fajmine majores et fortiores
mares prae caeteris admittunt, ad eos confugiunt, a juniori-
bus agitata?, qui hos in fugam conjiciunt." 44 A clergyman,
who has bred many pigs, assures me 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 antipa-
thies and preferences are frequently exhibited, and much
more commonly by the female than by the male. This
being the case, it is improbable that the unions of quad-
rupeds 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 charac-
ters in a higher degree than other males ; but what these
characters are, we can seldom or never discover with cer-
tainty.

« 'Trait6 de l'H6r6d. Nat.' torn. ii. 1850, p. 296.
44 * Amcenitates Acad.' voL iv. 1788, p. 160.

Chap. XVIII.]

VOCAL ORGANS.

261

CHAPTER XVIII.

Secondary Sexual Characters of Mammals — continued.

Voice. — Remarkable Sexual Peculiarities in Seals. — Odor. — Development
of the Hair. — Color of the Hair and Skin. — Anomalous Case of the
Female being more ornamented than the Male. — Color and Ornaments
due to Sexual Selection. — Color acquired for the Sake of Protection.—
Color, though common to both Sexes, often due to Sexual Selection.—
On the Disappearance of Spots and Stripes in Adult Quadrupeds. —
On the Colors and Ornaments of the Quadrumana. — Summary.

Quadrupeds use their voices for various purposes, as
a signal of danger, as a call from one member 'of a troop
to another, or from the mother to her lost offspring, or
from the latter for protection to their mother ; but such
uses need not here be considered. We are concerned only
witli the difference between the voices of the two sexes,
for instance, between that of the lion and lioness, or of the
bull and cow. Almost all male animals use their voices
much more during the rutting-season than at any other
time ; and some, as the giraffe and porcupine,1 are said lo
be completely mute excepting at this season. As the
throats (i. c., the larnyx and thyroid bodies3) of stags be-
come periodically enlarged at the commencement of the
breeding-season, it might be thought that their powerful
voices must be then in some way of high importance t«»
them; but this is very doubtful. From information given
to me by two experienced observers, ]\lr. McNeill and Sir
P. Egerton, it seems that young stagH under three years

1 Owin, ' Anntoiii) of Yritcl.nit. x/ vol. iii. |>. r»H,V 1 Ihid. p. r.nr,.

262

SEXUAL SELECTION: MAMMALS. [Part IT.

old do not roar or bellow ; and that the old ones begin
bellowing at the commencement of the breeding-season,
at first only occasionally and moderately, while they rest-
lessly wander about in search of the females. Their bat-
tles are prefaced by loud and prolonged bellowing, but
during the actual conflict they are silent. Animals of all
kinds which habitually use their voices, utter various
noises under any strong emotion, as when enraged and
preparing to fight ; but this may merely be the result of
their nervous excitement, which leads to the spasmodic
contraction of almost all the muscles of the body, as when
a man grinds his teeth and clinches his hands in rage or
agony. No doubt stags challenge each other to mortal
combat by bellowing ; but it is not likely that this habit
could have led through sexual selection, that is, by the
loudest-voiced males having been the most successful in
their conflicts, to the periodical enlargement of the vocal
organs ; for the stags with the most powerful voices, unless
at the same time the strongest, best-armed, and most coura-
geous, would not have gained any advantage over their
rivals with weaker voices. The stags, moreover, which
had weaker voices, though not so well able to challenge
other stags, would have been drawn to the place of com-
bat as certainly as those with stronger voices.

It is possible that the roaring of the lion may be of
some actual service to him in striking terror into his ad-
versary ; for when enraged he likewise erects his mane
and thus instinctively tries to make himself appear as ter-
rible as possible. But it can hardly be supposed that the
bellowing of the stag, even if it be of any service to him
in this way, can have been important enough to have led
to the periodical enlargement of the throat. Some writ-
ers suggest that the bellowing serves as a call to the fe-
male ; but the experienced observers above quoted inform
me that female deer do not search for the male, though

Chap. XVIII.] VOCAL ORGANS.

263

the males search eagerly for the females, as indeed might
be expected from what we know of the habits of other
male quadrupeds. The voice of the female, on the other
hand, quickly brings to her one or more stags,3 as is well
known to the hunters who in wild countries imitate her
cry. If we could believe that the male had the power to
excite or allure the female by his voice, the periodical en-
largement of his vocal organs would be intelligible on the
principle of sexual selection, together with inheritance
limited to the same sex and season of the year ; but we
have no evidence in favor of this view. As the case
stands, the loud voice of the stag during the breeding-sea-
son does not seem to be of any special service to him,
either during his courtship, or battles, or in any other
way. But may we not believe that the frequent use of
the voice, under the strong excitement of love, jealousy,
and rage, continued during many generations, may at last
have produced an inherited effect on the vocal organs of
the stag, as well as of other male animals ? This appears
to me, with our present state of knowledge, the most prob-
able view.

The male gorilla has a tremendous voice, and when
adult is furnished with a laryngeal sac, as is likewise the
adult male orang.4 The gibbons rank among the noisiest
of monkeys, and the Sumatra species (Ilylobates syndac-
tylus) is also furnished witli a laryngeal sac ; but Mr.
Blyth, who has had opportunities for observation, does
not believe that the male is more noisy than the female.
Hence, these latter monkeys probably use their voices as a
mutual call; and this is certainly the case with some
quadrupeds, for instance, with the beaver.6 Another gil*

8 See, for instance, Major W. Ross King ('The Sportsman in Canada,'
1800, pp. 53, 131) on the habits of the moose and wild reindeer.
4 Owen, •Anatomy of Vertebrates,' vol. iii. p. t'.on.
6 Mr. Green, in ' Journal of Linn. Soe.' vol. x. Zoology, lsi'.'.i, p. :5<*.2.

.204 SEXUAL SELECTION : MAMMALS. [Pakt II.

bon, the II. agiUs, is highly remarkable, from having the
power of emitting a complete and correct octave of musi-
cal notes,6 which we may reasonably suspect serves as a
sexual charm ; but I shall have to recur to this subject in
the next chapter. The vocal organs of the American
Mycetes caraya are one-third larger in the male than in
the female, and are wonderfully powerful. These mon-
keys, when the weather is warm, make the forests resound
during the morning and evening with their overwhelming
voices. The males begin the dreadful concert, in which
the females, with their less powerful voices, sometimes
join, and which is often continued during many hours.
An excellent observer, Rengger,* could not perceive that
they were excited to begin their concert 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 power-
ful voices in order to beat their rivals and to charm the
females — or whether the vocal organs have been strength-
ened and enlarged through the inherited effects of long-
continued use without any particular good being gained
— I will not pretend to say ; but the former view, at least
in the case of the Hylobates agilis, seems the most prob-
able.

I may here mention two very curious sexual pecu-
liarities occurring in seals, because they have been sup-
posed by some writers to affect the voice. The nose of
the male sea-elephant {Macrorhinus proboscideus), when
about three years old, is greatly elongated during the
breeding-season, and can then be erected. In this state it
ts sometimes a foot in length. The female at no period
of life is thus provided, and her voice is different. That

* C. L. Martin, 4 General Introduction to the Nat Hist of Mamni.
Animals/ 1841, p. 481.

1 4 Naturgcschichte der Saugethiere von Paraguay,' 1830, s. 15, 21

Chap. XVIIL] ODORS EMITTED.

265*

of the male consists of a wild, hoarse, gurgling noise,
which is audible at a great distance, and is believed to be
strengthened by the proboscis. Lesson compares the
erection of the proboscis to the swelling of the wattles of
male gallinaceous birds while they court the females. In
another allied kind of seal, namely, the bladder-nose
(Cystophora cristata), the head is covered by a great
hood or bladder. This is internally supported by the sep-
tum of the nose, which is produced far backward and rises
into a 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 by man they likewise roar or bel-
low ; and whenever irritated the bladder is inflated.
Some naturalists believe that the voice is thus strength-
ened, 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. This
latter view is not probable, if what the sealers have long
maintained is correct, namely, that the hood or bladder is
very poorly developed in the females and in the males
while young.8

Odor. — With some animals, as with the notorious
skunk of America, the overwhelming odor which they
emit appears to serve exclusively as a means of defence.
With shrew-mice (Sorex) both sexes possess abdominal

8 On tho Boa-elephant, sec an article by Lesson, in 4 Diet. GUlS, EDlt
Nat.' torn. xiii. p. 41H. For the Cystophora or Stemnmtopus, see Dr.
Dckay, 'Annuls of Lyceum of Nat. Hist. New York,' vol. i. I VI. p. '.'I.
Pennant has also collected information from the sealers on this animal.
The fullest account is pven l>\ Mr. lb-own, who <loubts about the rudi-
mentary condition of the bladder in the female, in ' I'roe. Zoolo^. Soe.'
18f)H, p. 485.

266

SEXUAL SELECTION: MAMMALS. [Pakt ll.

scent-glands, and tliere can be little doubt, from the man-
ner in which their bodies are rejected by birds and bettfep
of prey, that their odor is protective ; nevertheless, the
glands become enlarged in the males during the breeding-
season. In many quadrupeds the glands are of the same
size in both sexea ; 9 but their use is not known. In other
species the glands are confined to the males, or are more
developed in them than in the females ; and they almost
always become more active during the rutting-season.
At this period the glands on the sides of the face of the
male elephant enlarge and emit a secretion having a strong
musky odor.

The rank effluvium of the male goat is well known,
and that of certain male deer is wonderfully strong and
persistent. On the banks of the Plata I have perceived
the whole air tainted with the odor of the male Cervus
campestris, at the distance of half a mile to the leeward
of a herd ; and a silk handkerchief, in which I carried home
a skin, though repeatedly used and washed, retained,
when first unfolded, traces of the odor for one year and
seven months. This animal does not emit its strong odor
until more than a year old, and if castrated while young
never emits it.10 Besides the general odor, with which
the whole body of certain ruminants appears to be perme-
ated during the breeding-season, many deer, antelopes,
sheep, and goats, possess odoriferous glands in various
situations, more especially on their faces. The so-called

• As with the castoreum of the beaver, see Mr. L. II. Morgan's most
interesting work, 'The American Beaver,' 1868, p. 300. Pallas ('Spic
Zoolog.' fasc. viii. 1779, p. 23) has well discussed the odoriferous glands
of mammals. Owen ('Anat. of Vertebrates,' vol. iii. p. 634) also gives
an account of these glands, including those of the elephant, and (p. 763)
those of shrew-mice.

10 Rengger, 1 Naturgeschichte der Saugethiere von Paraguay,' 1830, s.
355. This observer also gives some curious particulars in regard to the
odor emitted.

Chap. XVIIL]

ODORS EMITTED.

267

tear-sacs or suborbital pits come under this head. These
glands secrete a semifluid fetid matter, which is sometimes
so copious as to stain the whole face, as I have seen in the
case of an antelope. They are " usually larger in the male
than in the female, and their development is checked by
castration." 11 According to Desmarest they are altogether
absent in the female of Antilope subgutturosa. Hence,
there can be no doubt that they stand in some close rela-
tion with the reproductive functions. They are also
sometimes present, and sometimes absent, in nearly-allied
forms. In the adult male musk-deer (Moschus moschife-
rus), a naked space round the tail is bedewed with an
odoriferous fluid, while 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-sac, from its
position, is necessarily confined to the male, and forms an
additional scent-organ. It is a singular fact that the mat-
ter secreted by this latter gland does not, according to
Pallas, change in consistence, or increase in quantity,
during the rutting-scason ; nevertheless, this naturalist
admits that its presence is in some way connected with
the act of reproduction. He gives, however, only a con-
jectural and unsatisfactory explanation of its use.13

In most cases, when during the breeding-season the
male alone emits a strong odor, this probably serves to ex-
cite or allure the female. We must not judge on this head
by our own taste, for it is well known that rats arc
enticed by certain essential oils, and cats by valerian,
substances which are far from agreeable to us; and that
dogs, though they will not eat carrion, sniff and roll in it.

11 Owen, 'Anatomy of Vertebrates,' vol. lii. p. (,;;•_'. See, also, Dr.
Mnrie's observations on tlieir glands in ' Proo. Zoolog. Boo.' 1S7«», p, :;io.
Desmarest, Oil the Anti/oj>e Hiibf/ittturom, ' Mummalo^ie,' lS'JO, p I .v..

M Pallas, ' Spicilegiu Zoolog. ' fuse. xiii. 1799, p. Mj De>moulins?
'Diet. Glass. d'Hist. Nat; torn. ill. i». 586.

268

SEXUAL SELECTION: MAMMALS. [Pakt II.

From the reasons given when discussing the voice of lire*
stag, we may reject the idea that the odor serves to bring
the females from a distance to the males. Active and long-
continued use cannot here have come into play, as in t In-
case of the vocal organs. The odor emitted must be of"
considerable importance to the male, inasmuch as large
and complex glands, furnished with muscles for everting
the sac, and for closing or opening the orifice, have in
some cases been developed. The development of than
organs is intelligible through sexual selection, if the more
odoriferous males are the most successful in winning the
females, and in leaving offspring to inherit their gradually-
perfected glands and odors.

Development of the Hair. — We have seen that male
quadrupeds often have the hair on their necks and shoul-
ders much more developed than in the females ; and many
additional instances could be gi?en. This sometimes
serves as a defence to the male during his battles; but
whether the hair in most cases has been specially devel-
oped for this purpose is very doubtful. We may feel
almost certain chat this is not the case, when a thin and
narrow crest.runs along the whole length of the back ; for
a crest of this kind would afford scarcely any protection,
and the ridge of the back is not a likely place to be in-
jured ; nevertheless such crests are sometimes confined to
the males, or are much more developed in them than in
the females. Two antelopes, the Tragelaphus scriptus "
(see Fig. 68, p. 285) and Portax picta, may be given as
instances. The crests of certain stags and of the male
wild-goat stand erect, when these animals are enraged or
terrified ; 14 but it can hardly be supposed that they have

" Dr. Gray, ' Gleanings from the Menagerie at Knowsley,' pL 28.

14 Judge Caton on the wapiti, 4 Transact. Ottawa Acad. Nat. Sciences,'
1868, pp. 36, 40 ; Blyth, 1 Land and Water,' on Capra agagrut, 1867,
p. 87.

Chap. XVIII.] DEVELOPMENT OF HAIR.

269

been acquired for the sake of exciting fear in their ene-
mies. One of the above-named antelopes, the Portax
picta, has a large, well-defined brush of black hair on the
throat, and this is much larger in the male than in the
female. In the Ammotragus tragelaphus of North Africa,
a member of the sheep family, the front-legs are almost
concealed by an extraordinary growth of hair, which de-
pends 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. The bull alone has curled
hair on the forehead.16 In three closely-allied subgenera
of the goat family, the males alone possess beards, some-
times of a large size ; in two other subgenera both sexes
have a beard, but this disappears in some of the domestic
breeds of the common goat ; and neither sex of the Hemi-
tragus has a beard. In the ibex the beard is not devel-
oped during the summer, and is so small at other seasons
that it may be called rudimentary.16 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 Mjj/06-
tes caraya and Pithecia satanas (Fig. OG). So it is with
the whiskers of some species of Macacus,17 and, as we have
seen, with the manes of some species of baboons. Hut
with most kinds of monkeys (he various tufts of hair about
the face and head arc alike in both si xes.

He males of various members of the ()\ family (Bo-

,r' ' Hunter's Essays and Observations,' edited by Owen, 1861, vol. i.
p. 236.

Keo Dr. Cray's 'Cat. of Mammalia in Hritish Museum,' |>;ut iii.
1852, p. 144.

11 Render, ' Sau^elhiere,' etc., s. 11 ; Desman ■•■it, ' Mammalo^o,' p. 00.

270 SEXUAL- SELECTION: MAMMALS. [I'aut II.

vidrc), and of certain antelopes, are furnished with a dew-
lap, 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 diiferences as these ? No one will pretend that the

Fio. 66.-Ptthecl» Satanu, male (from Brchm).

beards of certain male goat*, or the dewlap of the bnH
or the erosK ,.f hair ah.,,* ,!,, l,„ ks of ,(Ttain ,„al, ante'
lopes .are of any direct or ordinary use to them. It is
possible that the immense beard of the male Pithed*,
and the large beard of the male Orang, may protect their
Jhroats when fighting; for the keepers in the Zoological
Gardens inform me that many monkeys attack each other
by the throat : but if is not probable that the beard has

Chap. XVIIL] DEVELOPMENT OF HAIR.

271

been developed for a distinct purpose from that which the
whiskers, mustache, and other tufts of hair on the face,
serve ; and no one will suppose that these are useful as a
protection. Must we attribute to mere purposeless varia-
bility* in the male all these appendages of hair or skin?
It cannot be denied that this is possible ; for, with many
domesticated quadrupeds, certain characters, apparently
not derived through reversion from any wild parent-form,
have appeared in, and are confined to, the males, or are
more largely developed in them than in the females — for
instance, the hump in the male zebu-cattle of India, the
tail in fat-tailed rams, the arched outline of the forehead
in the males of several breeds of sheep, the mane in the
ram of an African breed, and, lastly, the mane, long hairs
on the hinder legs, and the dewlap in the male alone, of
the Berbura goat.18 The mane which occurs in the rams
alone of the above-mentioned African breed of sheep, is a
true secondary sexual character, for it is not developed,
as I hear from Mr. Winwood Reade, if the animal be cas-
trated. Although we ought to be extremely cautious, as
shown in my work on " Variation under Domestication,"
in concluding that any character, even with animals kepi
by semi-civilized people, has not been subjected to sclec-
tion by man, and thus augmented ; yet in the cases just
specified this is improbable, more especially as the charac-
ters are confined to the males, or are more strongly devel-
oped in them than in the females. II* it were positively
known that the African ram with a mane was descended

from the same primitive stook wiili the other breeds of

sheep, or the Berbura male goat with his mane, dew lap,
etc., from the same stock with other goats ; and if selee-

IH Sc<« the rliaplrrs on thrsc nrvcral animal* in vol. i. of nn 1 Varia-
tion of An'mial* nnoVr Doni^tit-ation ; ' alxo vol. ii. \>. 7:> ; al " ohap w.
on the practice «>l m-lcction I ► v Hrmi ri\ ili/nl |ici.|.|<\ hn llu< Itcrlniru
goat, him' Dr. Ci.o, ' < 'atalopi.-,' il.i.l. p. 1 r. 7 . •

272

SEXUAL SELECTION: MAMMALS.

[Part EC

tion lias not been applied to these characters, then the}
must he due to simple variability, together with sexually-
limited inheritance.

In this case it would appear reasonable to extend the
same view to the many analogous characters occurring in
animals under a state of nature. Nevertheless, I cannot
persuade myself that this view is applicable in many
cases, as in that of the extraordinary development of hair
on the throat and fore-lei's of the male Ammotraurus, or

O Of

of the immense beard of the male Pithecia. With those
antelopes in which the male when adult is more strongly
colored than the female, and with those monkeys in which
this is likewise the case, and in which the hair on the face
is of a different color from that on the rest of the la ad,
being arranged in the most diversified and elegant man-
ner, it seems probable that the crests and tufts of hair
have been acquired as ornaments ; and this I know is the
opinion of some naturalists. If this view be correct,
there can be little doubt that they have been acquired, or
at least modified, through sexual selection.

Color of the Hair and, of the Naked Skin. — I will
tirst give briefly all the cases, known to me, of male quad-
rupeds differing in color from the females. With Marsu-
pials, 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 Didelphis opossum of Cayenne the female
is said to be a little more red than the male. With Ro-
dents Dr. Gray remarks: "African squirrels, especially
those found in the tropical regions, have the fur much
brighter and more vivid at some seasons of the year than

" Otphranter rw/W, Gould, 4 Mammals of Australia,' voL ii. 1863.
On the Didelphis, Desmarest 1 Mammalogie,' p. 256.

Chap. XVIII.] ORNAMENTAL COLORS.

273

at others, and the fur of the male is generally brighter
than that of the female." 20 Dr. Gray informs me that he
specified the African squirrels, because, from their unusu-
ally bright colors, they best exhibit this difference. The
female of the Mus minutus of Russia is of a paler and
dirtier tint than the male. In some few bats the fur of
the male is lighter and brighter than in the female.21

The terrestrial Carnivora and Insectivora rarely exhib-
it sexual differences of any kind, and their colors are al-
most always exactly the same in both sexes. The ocelot
{Felis partialis), however, offers an exception, for the col-
ors of the female, compared with those of the male, are
"moins apparentes, le fauve etant plus terne, le blanc
moins pur, les raies ayant moins de largeur et les taches
moins de diametre." 22 The sexes of the allied Fells mitis
also differ, but even 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 color, and
they present, as we have already seen, other remarkable
sexual differences. Thus the male of the Otaria nigres-
cens of the southern hemisphere is of a rich brown shade
above ; while the female, who acquires her adult tints
earlier in life than the male, is dark gray above, the young
of both sexes being of a very deep chocolate color. The
male of the northern Phoca Groenlandica is tawny gray,
with a curious saddle-shaped dark mark on the back; the
female is much smaller, and has a very different appear-
ance, being "dull white or yellowish straw-color, with a

N ' Annuls and Mug. of N'ut. Hist.' Nov. lsr.7, p. On the Mus

tni n u( nn, DcHniarcst, ' Mainiimlopc,' p. :i<>|.

n .F. A. Allen, in ' Hulletin of Mus. Coinp. Zoning, of Cainhi id^e, Tin-
ted Slut cm,' 1869, p. 207.

77 Dosmurt-Ht, ' Miiinniulogie,' Is-jo, p. On Ftlis //i »//.<, K, n ; n,

ibid m. h*4.

274

SEXUAL SELECTION: MAMMALS. [Part II.

tawny hue on the back;" the young at first are pure
white, and can " hardly be distinguished among the icy
hummocks and snow, their color thus acting as a protec-
tion." 23

With Ruminants sexual differences of color occur more
commonly than in any other order. A difference of this
kind is general with the Strepsicerene antelopes ; thus the
male nilghau (Portax picta) is bluish-gray and much
darker than the female, with the square white patch on
the throat, the white marks on the fetlocks, and the black
spots on the ears, all much more distinct. We have seen
that in this species the crests and tufts of hair are likewise
more developed in the male than in the hornless female.
The male, as I am informed by Mr. Blyth, without shed-
ding his hair, periodically becomes darker during the
breeding-season. Young males cannot be distinguished
from young females until above twelve months old ; and
if the male is emasculated before this period, he never,
according to the same authority, changes color. The im-
portance of this latter fact, as distinctive of sexual color-
ing, becomes obvious, when we hear24 that neither the red
summer-coat nor the blue winter-coat of the Virginian deer
is at all affected by emasculation. With most or all of
the highly-ornamented species of Tragelaphus the males
are darker than the hornless females, and their crests of
hair are more fully developed. In the male of that mag-
nificent antelope, the Derbyan Eland, the body is redder,
the whole neck much blacker, and the white band which
separates these colors, broader, than in the female. In
the Cape Eland also, the male is slightly darker than the
female.28

23 Dr. Murie on the Otaria, ' Proc. Zool. Soc.' 1869, p. 108. Mr. R.
Brown, on the P. Groenlandica, ibid. 1868, p. 417. See also on the colors
of seals, Desmarest, ibid. pp. 243, 249.

24 Judge Caton, in 'Trans. Ottawa Acad, of Nat. Sciences.' 1868, p. 4.
96 Dr. Gray, 1 Cat of Mamm. in Brit. Mus.' part iii. 1852, pp. 134-142;

Chap. XVIIL] ORNAMENTAL COLORS. 275

In the Indian Black-buck (A. bezoartica), which belongs
to another tribe of antelopes, the male is very dark, almost
black ; while the hornless female is fawn-colored. We
have in this species, as Mr. Blyth informs me, an exactly
parallel series of facts as with the JPortax picta, namely, in
the male periodically changing color during the breeding-
reason, in the effects of emasculation on this change, and
in the young of both sexes being undistinguishable from
each other. In the Antilope niger the male is black, the
female as well as the young being brown ; in A. sing-sing
the male is much brighter colored 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 as in the female brown ; in the
brindled gnu (A. gorgon) "the colors of the male are
nearly the same as those of the female, only deeper and
of a brighter hue."26 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
color. The emasculated bull reverts to the color of the
female. The female Kemas goat is paler, and the female
Gapra cegagrus is said to be more uniformly tinted than

also Dr. Gray, ' Gleanings from the. Menagerie of Knowsley,' in which
there is a splendid drawing of the Oreas Derbianus : see the text on
Tragelaphus. For the Cape Eland {Oreas canna), sec Andrew Smith,
'Zoology of South Africa,' pis. 41, 42. There are also many of these
antelopes in the Zoological Society's Gardens.

26 On the Ant. niger, sec 4 Proc. Zool. Soc' 1850, p. 188. With re-
gpect to an allied species, in which there is an cqnal sexual difference in
color, sec Sir S. Baker, 1 The Albert Nyan/.a,' 1806, vol. ii. p. 327. For
the A. ting-sing, Gray, 'Cat. B. Mus.' p. 100. Desmarest, ' Matnmalogie,'
p. 408, on the A. caama. Andrew Smith, 'Zoology of South Africa,' on
the Gnu.

276

SEXUAL SELECTION : MAMMALS. [Part DL

their respective males. Deer rarely present any sexual
differences in color. Judge Caton, however, informs me
that with the males of the Wapiti deer ( Cervus Canaden-
sis) the neck, belly, and legs, are much darker than the
same parts in the female ; but during the winter the darker
tints gradually fade away and disappear. I may lure
mention that Judge Caton has in his park three races of
the Virginian deer, which differ slightly in color, but the
differences are almost exclusively confined to the blue
winter or breeding coat ; so that this case may be com-
pared with those given in a previous chapter of closely-
allied or representative species of birds which differ from
each other only in their nuptial plumage." The females
of Cervus paludosus of South 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
characterize the adult males." Lastly, the mature male
of the beautifully colored and spotted Axis deer is con-
siderably darker, as I am informed by Mr. Blyth, than
the female •, and this hue the castrated male never ac-
quires.

The last Order which we have to consider — for I am
not aware that sexual differences in color occur in the
other mammalian groups — is that of the Primates. The
male of the Lemur macaco is coal-black, while the female
is reddish-yellow, but highly variable in color." Of the
Quadrumana of the New World, the females and young
of Mycetes caraya are grayish-yellow and alike ; in the

" 4 Ottawa Academy of Sciences,' May 21, 1868, pp. 3, 6.

w S. Miiller, on the Banteng, 'Zoog. Indischen ArchipeL' 1839-1844,
tab. 35 : see also Raffles, as quoted by Mr. Blyth, in • Land and Water,'
1867, p. 476. On goats, Dr. Gray, 'Cat. Brit Mus.' p. 146; Desmarest,
' Mammalogie,' p. 482. On the Cervus paludosus, Rcngger, ibid. s. 345.

n Sclater, ' Proc. Zool. Soo.' 18«6, p. 1. The same fact has also been
fully ascertained by MM. Pollen and Van Dam.

Chap. XVIII.] ORNAMENTAL COLORS.

27?

second year the young male becomes reddish-brown, in
the third year black, excepting the stomach, which, how-
ever, becomes quite black in the fourth or fifth year. There
is also a strongly-marked difference in color between the
sexes in Mycetes seniculus and Cebus capucinus / the young
of the former and I believe of the latter species resembling
the females. With Pithecia leucocephala the young like-
wise resemble the females, which are brownish-black above
and light rusty-red beneath, the adult males being black.
The ruff of hair round the face of Ateles marginatus is
tinted yellow in the male and white in the female. Turn-
ing to the Old World, the males of Hylobates hoolock are
always black, with the exception of a white band over the
brows ; the females vary from whity-brown to a dark
tint mixed with black, but are never wholly black.30 In
the beautiful Cercopithecus Diana the head of the adult
male is of an intense black, while that of the female is dark
gray ; in the former the fur between the thighs is of an
elegant fawn-color, in the latter it is paler. In the equally
beautiful and curious mustache monkey (Cercopithecus
cephus) the only difference between the sexes is that the
tail of the male is chestnut and that of the female gray ;
but Mr. Bartlett informs me that all the hues become
more strongly pronounced in the male when adult, while
in the female they remain as they were during youth.
According to the colored figures given by Solomon MtUler,
the male of Semnopitheras chnjsomelas is nearly black,
the female being pale brown. In the Cercoj>it/t< <-ks qyno-
NHinis and griseo-viridis one part of the body which is con-
fined to the male sex is of the most brilliant blue or green,

30 On MycotcB, Hcn^Kcr, ibid. h. M; imd Urchin, ' lllustrii tc.s Tliicr
leben,' 15. i. u. '.••'», 1<»7. On Ateles, Dcstniircst, ' Maintimlopu,' p.
On HylobntcH, Mlvth, ' I.niwl and Wain,' is,,;, ,,. i:;y On tin S im.,..

pltheoui, B. Mull, i, 'Zoos, [ndinchen ArohlpeL' tab. x.

278

SEXUAL SELECTION: MAMMALS. [Paht II.

and contrasts strikingly with the nuked skin on the hinder
part of the body, which is vivid red.

Lastly, in the Baboon family, the adult male of Cyno-
cephalus hamadryas differs from the female not only by
his immense mane, but slightly in the color of the hair
and of the naked callosities. In the drill (Cyn<><'< phutus
Iciirophinan) the females and young are much paler-
colored, with less green, than the adult males. No
other member of the whole class of mammals is colore 1
in so extraordinary a manner as the adult male mandrill
( Cynoccphalus mormon). The face at this age becomes
of a fine blue, with the ridge and tip of the nose of the
most brilliant red. According to some authors, the face
is also marked with whitish stripes, and is shaded in parts
with black, but the colors appear to be variable. On the
forehead there is a crest of hair, and on the chin a yellow
beard. " Toutes les parties superieures de leurs cuisses et
lc grand espace nu de leurs fesses sont dgalement colores
du rouge le plus vif, avec un m61ange de bleu qui ne
manque reellement pas d'elegance." " When the animal
is excited all the naked parts become much more vividly
tinted. Several authors have used the strongest expres-
sions in describing these resplendent colors, which they
compare with those of the most brilliant birds. Another
most remarkable peculiarity is that when the great ca-
nine teeth are fully developed, immense protuberances of
bone are formed on each cheek, which are deeply fur
rowed longitudinally, and the naked skin over them is
brilliantly colored, as just described. (Fig. 67.) In the
adult females and in the young of both sexes these protu-
berances are scarcely perceptible; and the naked parts
are much less brightly colored, the face being almost

n Gervais, 'Hist Nat. dea Mammiferes,' 1854, p. 103. Figures are
given of the skull of the male. Desmarest, 1 Mammalogie,' p. 70.
Geoffrey St-Hilairc and F. Cuvier, 'Hist. Nat. dea Maiunx' 1824, torn. i.

Chap. XVIII.]

ORNAMENTAL COLORS.

2^9

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 strong-
ly or brightly colored than the female, and differs in a

Vui. <;?.- Hraci of male Mandi 111 (from < tanrali 'Hist. Nut »i«-h ICftflUDilw**')'

greater degree from the young of both sexes. Bui u ;>
reversed style of coloring is oharaoteristio <»i ths two

sexes With some |< \\ birds, BO with the iihesnt monkey

(MarariiH rhtsns) i he leimile bai :i large surface of naked

280 SEXUAL SELECTION : MAMMALS [Paht II.

skin round the tail, of a brilliant carmine red, which pe-
riodically becomes, as I was assured by the keepers in the
Zoological Gardens, even more vivid, and her face is also
jpale red. On the other hand, with the adult male and with
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, shows a trace of red. It appears, however, from some
published accounts, that the male does occasionally, or
during certain seasons, exhibit some traces of the red.
Although he is thus less ornamented than the female, yet
in the larger size of his body, larger canine teeth, more
developed whiskers, more prominent superciliary ridges,
he follows the common rule of the male excelling the
female.

I have now given all the cases known to me of a dif-
ference- in color between the sexes of mammals. The
colors of the female either do not differ in a sufficient
degree from those of the male, or are not of a suitable
nature to afford her protection, and therefore cannot be
explained on this principle. In some, perhaps in many
cases, the differences may be the result of variations con-
fined to one sex and transmitted to the same sex, without
any good having been thus gained, and therefore without
the aid of selection. We have instances of this kind with
our domesticated animals, as in the males of certain cats
being rurty-red, while the females are tortoise-shell col-
ored. Analogous cases occur under nature : Mr. Bartlctt
has seen many black varieties of the jaguar, leopard, vul-
pine, phal anger, and wombat; and he is certain that all,
or nearly all, were males. On the other hand, both sexes
of wolves, foxes, and apparently of American squirrels,
are occasionally born black. Hence it is quite possible
that with some mammals the blackness of the males, es-
pecially when this color is congenital, may simply be the

Chap. XVIIL] ORNAMENTAL COLORS.

281

result, without the aid of selection, of one or more varia-
tions having occurred, which from the first were sexually
limited in their transmission. Nevertheless, it can hardly
be admitted that the diversified, vivid, and contrasted col-
ors of certain quadrupeds, for instance, of the above-men-
tioned monkeys and antelopes, can thus be accounted for.
We should bear in mind that these colors do not appear
in the male at birth, as in the case of most ordinary va-
riations, but only at or near maturity ; and that, unlike
ordinary variations, if the male be emasculated, they
never appear or subsequently disappear. It is on the
whole a much more probable conclusion that the strong-
ly-marked colors and other ornamental characters of
male quadrupeds are beneficial to them in their rivalry
with other males, and have consequently been acquired
through sexual selection. The probability of this view is
strengthened by the differences in color between the sexes
occurring almost exclusively, as may be observed by
going through the previous details, in those groups and
sub-groups of mammals which present other and distinct
secondary sexual characters ; these being likewise due to
the action of sexual selection.

Quadrupeds manifestly take notice of color. Sir S.
Baker repeatedly observed that the African elephant and
rhinoceros attacked with special fury white or gray hoi st s.
I have elsewhere shown 3J that half-w ild horses apparently
prefer pairing with those of the same color, and that herds
of fallow-deer of a different color, though living together,
have long kept distinct. It is a more significant fact that
a female zebra would not admit the addresses of a male
ass until he was painted so as to resemble a zebra, and
then, as John Hunter remarks, " she received him ver)
readily. In this curious fact, we have instinct excited by

M,Tli<" Variation of AniinalM awl I'lanM iiihI.t l>onirsti« ation,' 1m'. s,
to!, ii. pp. 102, 108.

282

SEXUAL SELECTION: MAMMALS.

[Part II.

mere color, which had so strong an effect as to get the
better of every thing else. But the male did not require
this, the female being an animal somewhat similar to him-
self, was sufficient to rouse him." M

In an early chapter we have seen that the mental
powers of the higher animals do not differ in kind, though
so greatly in degree, from the corresponding powers of man,
especially of the lower and barbarous races ; and it would
appear that even their taste for the beautiful is not widely
different from that of the Quadrumana. As the negro of
Africa raises the flesh on his face into parallel ridges "or
cicatrices, high above the natural surface, which unsight-
ly deformities are considered great personal attractions " M
— as negroes, as well as savages in many parts of the
world, paint their faces with red, blue, white, or black bars
— so the male mandrill of Africa appears to have acquired
his deeply-furrowed and gaudily-colored 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 have been colored for the sake of orna-
ment even more brilliantly than the face; but this is really
not more strange than that the tails of many birds should
have been especially decorated.

With mammals we do not at present possess any evi-
dence that the males take pains to display their charms
before the female ; and the elaborate manner in which this
is performed by male birds, is the strongest argument in
favor of the belief that the females admire, or are excit-
ed by, the ornaments and colors displayed before them.
There is, however, a striking parallelism between mam-
mals and birds in all their secondary sexual characters,
namely, m their weapons for fighting with rival males, in

M< Essays and Observations by J. Hunter,' edited by Owen, 1861,
vol. i. p. 194.

** Sir S. Baker, ' The Nile Tributaries of Abyssinia,' 1867.

Chap. XVIII.] EQUAL TRANSMISSION

283

their ornamental appendages, and in their colors. In both
classes, when the male differs from the female, the young
of both sexes almost always resemble each other, and in a
large majority of cases resemble the adult female. In both
classes the male assumes the characters proper to his sex
shortly before the age for reproduction; if emasculated
he either never acquires such characters or subsequently
loses them. In both classes the change of color is some-
times 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
colored than the female, and is ornamented with larger
crests either of hair or feathers, or other 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 odor-
iferous than the female. In both classes the voice of the
male is more powerful than that of the female. Consider-
ing this parallelism there can be little dcubt that the same
cause, whatever it may be, has acted on mammals and
birds ; and the result, as far as ornamental characters are
concerned, may safely be attributed, as it appears to me,
to the long-continued preference of the individuals of one
sex for certain individuals of the opposite sex, combined
with their success in leaving a larger number of offspring
to inherit their superior attractions.

Equal Transmission of Ornamental Characters to l><>th
Sexes. — With many birds, ornaments, which analogy leads
us to believe were primarily acquired by the males, have
been transmitted equally, or almost equally, to both sexes j

and we may now inquire how far this view may be ex-
tended to mammals. With a considerable number of spc-

cies, especially the smaller, kinds, both sexes have been
colored, Independently of sexual selection, fox the lake of

284

SEXUAL SELECTION: MAMMALS. [Part II.

protection ; but not, as far as I can judge, in so many
cases, nor in nearly so striking a manner as in most of the
lower classes. Audubon remarks that he often mistook
the musk-rat," while sitting on the banks of a muddy
stream, for a clod of earth, so complete was the resem-
blance. The hare on her form is a familiar instance of
concealment through color ; yet this principle partly fails
in a closely-allied species, namely, the rabbit, for, as this
animal runs to its burrow, it is made conspicuous to the
sportsman and no doubt to all beasts of prey, by its up-
turned pure-white tail. No one has ever doubted that the
quadrupeds which inhabit snow-clad regions have been
rendered white to protect them from their enemies, or to
favor their stealing on their prey. In regions where snow
never lies long on the ground a white coat would be inju-
rious ; consequently species thus colored are extremely
rare in the hotter parts of the world. It deserves notice
that many quadrupeds, inhabiting moderately cold regions?
although they do not assume a white winter dress, become
paler during this season ; and this apparently is the direct
result of the conditions to which they have long been ex-
posed. Pallas " states that in Siberia a change of this na-
ture occurs with the wolf, two species of Mustela, the do-
mestic* horse, the Equus hemionus, the domestic cow, two
species of antelopes, the musk-deer, the roe, the elk, and
reindeer. The roe, for instance, has a red summer and a
grayish- white winter coat ; and the latter may perhaps
serve as a protection to the animal while 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

85 Fiber'zibdhicw, Audubon and Bachman, 1 The Quadrupeds of North
America,' 1846, p. 109.

36 'Novae species Quadrupcdum e Glirium ordine,' 1778, p. 7. What
I hare called the roc is the Capreolus %ibiriewi mbecaudaius of Pallas.

Chap. XVIII.] EQUAL TRANSMISSION. 285

with snow, the pale winter coats would probably be ren-
dered, through natural selection, whiter and whiter by de-#
grees, until they become as white as snow.

Although we must admit that many quadrupeds have

Flo. 88.— Tnffelaphnfl RCrlptUB, male (from (lie KiiowsKy Mi'im^-rio).

received their present lints :is :i protection, vet with m host
of species the colors arc far too conspicuous aiul too sin-
ga^arly arranged to allow us t<> suppose that they serve
for this purpose. We may take ae an illustration certain

antelopes: when we see thai the square white patch en

28G

SEXUAL SELECTION : MAMMALS. [Part It

the throat, the white marks on the fetlocks, and the round
black spots on the ears, are all more distinct in the male
of the Portax picta, than in the female — when we see that
the colors are more vivid, that the narrow white lines on
the flauk and the broad white bar on the shoulder are

Fio. 60.— Damalis pyi»ar£*a, male (from the Knowgley Mcnajrcric).

more distinct in the male 0rea8 Dcrbyaniis than in the fe-
male— when we see a similar difference between the s< \< s
of the curiously ornamented Tragelaphus scriptus (Fig.
68) — we may conclude that these colors and various
marks have been at least intensified through sexual selec-
tion. It is inconceivable that such colors and marks* can
be of any direct pr ordinary service to these animals ; and

Chap. XVIII.] EQUAL TRANSMISSION.

287

as they have almost certainly been intensified through
sexual selection, it is probable that they were originally
gained through this same process, and then partially
transferred to the females. If this view be admitted,
there can be little doubt that the equally singular colors
and marks of many other antelopes, though common to
both sexes, have been gained and transmitted in a like
manner. Both sexes, for instance, of the Koodoo {Stre}>
siceros Kudu, Fig. 62) have narrow white vertical lines on
their hinder flanks, and an elegant angular white mark on
their foreheads. Both sexes in the genus Damalis are very
oddly colored ; in D. pygarga the back and neck are pur-
plish-red, shading on the flanks into black, and abruptly
separated from the white belly and a large white space on
the buttocks ; the head is still more oddly colored, a large
oblong white mask, narrowly edged with black, covers the
face up to the eyes (Fig. 69) ; there are three white stripes
on the forehead, and the ears are marked with white.
The fawns of this species are of a uniform pale yellowish-
brown. In Damalis albifrons the coloring of the head
differs from that in the last species in a single white stripe
replacing the three stripes, and in the ears being almost
wholly white. 87 After having studied to the best of my
ability the sexual differences of animals belonging to all
classes, I cannot avoid the conclusion that the curiously-
arranged colors of many antelopes, though common to
both sexes, are the result of sexual selection primarily ap-
plied t o the male.

The same conclusion may perhaps be extended to the
tiger, one of the most beautiful animals in the world, the
sexes of which cannot, he distinguished by color, even by
t he dealers in wild beasts. Mr. Wallace behoves" that

31 Sec tin' line |. lairs in A. Smith's 'Zoology of South Afruu,' and Dr.

(Jruy's 'Gleanings from the Menagerie of Cnowilej.'

*" ' WcHtuiinHtcr Review, ' July 1, lsf,?, p. 5.

288

SEXUAL SELECTION: MAMMALS. [Pakt II.

the striped coat of the tiger " so assimilates with the ver-
tical stems of the bamboo, as to assist greatly in conceal-
ing him from his approaching prey." But this view does
not appear to me satisfactory. We have some slight evi-
dence that his beauty may be due to sexual selection, for
in two species of Felis analogous marks and colors are
rather brighter in the male than in the female. The Zebra
is conspicuously striped, and stripes on the open plains of
South Africa cannot afford any protection. Burchell" in
describing a herd says, "Their sleek ribs glistened in tin*
sun, and the brightness and regularity of their striped
coats presented a picture of extraordinary beauty, in which
probably they are not surpassed by any other quadruped."
Here we have no evidence of sexual selection, as through-
out the whole group of the Equidae, the sexes are identical
in color. Nevertheless, he who attributes the white and
dark vertical stripes on the flanks of various antelopes to
sexual selection, will probably extend the same view to
the Royal Tiger and beautiful Zebra.

We have seen in a former chapter that when young
animals belonging to any class follow nearly the same
habits of life with- their parents, and yet are colored in a
different manner, it may be inferred that they have re-
tained the coloring of some ancient and extinct progeni-
tor. In the family of pigs, and in the genus Tapir, the
young are marked with longitudinal stripes, and thus
differ from every 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 tin-
Axis deer, both sexes of which at all ages and during all
seasons are beautifully spotted (the male being rather
more strongly colored than the female) — to species in
which neither the old nor the young are spotted. I will

w 'Travels in South Africa,' 1824, vol il p. 315.

Chap. XVIII.] ' SPOTS AND STRIPES. 289

specify some of the steps in this series. The Mantchurian
deer (Cervus Mantchuricus) is spotted during the whole
year, but the spots are much plainer, as I have seen in the
Zoological Gardens, during the summer, when the gen-
eral color of the coat is lighter than during the winter,
when the general color is darker and the horns are fully
developed. In the hog-deer {Hyelaphus porcinus) the
spots are extremely conspicuous during the summer when
the coat is reddish-brown, but quite disappear during the
winter when the coat is brown.40 In both these species
the young are spotted. In the Virginian deer the young
are likewise spotted, and about five per cent, of the adult
animals living in Judge Caton's park, as I am informed
by him, temporarily exhibit at the period when the red
summer-coat is being replaced by the bluish winter-coat,
a row of spots on each flank, which are always the same
in number, though very variable in distinctness. From
this condition there is but a very small step to the com-
plete absence of spots at all seasons in the adults ; and
lastly, to their absence at all ages, as occurs with certain
species. From the existence of this perfect series, and
more especially from the fawns of so many species being
spotted, we may conclude that the now living members
of the deer family are the descendants of some ancient
species which, like the Axis deer, was spotted at all ages
and seasons. A still more ancient progenitor probably
resembled to a certain extent the Hyomoschus aquations
— for this animal is spotted, and the hornless males have
large exserted canine teeth, of which some few true deer
still retain rudiments. It offers, also, one of those inter-
esting cases of a form linking together two groups, as it is

40 Dr. flray, ' (ileaningH from the Menagerie of Knowtdey,' p. »>l. Mr.
Hlyth, in epeaking (' Land and Water,' 1869, p. 42) of the bog»doe» of
Ceylon, says it is more brightly spotted frith white than the OOJONBfOQ bog
deer, nt the 10810!) when it reiMWI Itf hoim

290 SEXUAL SELECTION: MAMMALS. [Part II.

intermediate in certain osteological characters between
the pachyderms and ruminants, which were formerly
thought to be quite distinct.41

A curious difficulty here arises. If we admit that col-
ored spots and stripes have been acquired as ornaments,
how comes it that so many existing deer, the descendants
of an aboriginally spotted animal, and all the species of
pigs and tapirs, the descendants of an aboriginally striped
animal, have lost in their adult state their former orna-
ments ? I cannot satisfactorily answer this question. We
may feel nearly sure that the spots and stripes disap-
peared in the progenitors of our existing species at or near
maturity, so that they were retained by the young, and,
owing to the law of inheritance at corresponding ages, by
the young of all succeeding generations. It may have
been a great advantage to the lion and puma, from the
open nature of the localities which they commonly haunt,
to have lost their stripes, and to have been thus rendered
less conspicuous to their prey ; and if the successive vari-
ations, by which this end was gained, occurred rather late
in life, the young would have retained their stripes, as we
know to be the case. In regard to deer, pigs, and tapirs,
Fritz Muller has suggested to me that these animals, by
the removal through natural selection of their spots or
stripes, would have been less easily seen by their enemies ;
and 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 ex-
planation, but it is rather strange that the young should
not have been equally well protected, and still more
strange that with some species the adults should have
retained their spots, either partially or completely, during
part of the year. We know, though we cannot explain

41 Falconer and Cautley, ' Proc. Geolog. Soc' 1843; and Falconer's
Pal. Memoirs,' vol. L p. 196.

Chap. XVIII.] QUADRUMANA.

291

the cause, that when the domestic ass varies and becomes
reddish-brown, gray or black, the stripes on the shoulders
and even on the spine frequently disappear. Very few
horses, except dun-colored kinds, exhibit 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 disappear-
ance of the spots and stripes in our adult existing deer,
pigs, and tapirs, may be due to a change in the general
color of their coats ; but whether this change was effected
through sexual or natural selection, or was due to the di-
rect action of the conditions of life, or some other unknown
cause, it is impossible to decicfe. An observation made by
Mr. Sclater well illustrates our ignorance of the laws which
regulate the appearance and disappearance of stripes;
the species of Asinus which inhabit the Asiatic conti-
nent are destitute of stripes, not having even the cross
shoulder-stripe, while those which inhabit Africa are con-
spicuously striped, with the partial exception of A. tamio-
pus, which has only the cross shoulder-stripe and generally
some faint bars on the legs ; and this species inhabits the al-
most intermediate region of Upper Egypt and Abyssinia.43

Quadrumana. — Before we conclude, it will be advisa-
ble to add a few remarks to those already given on the
ornamental characters of monkeys. In most of the spe-
cies the sexes resemble each other in color, but in some,
as we have seen, Uic males differ from the females, espe-
cially in the color of the naked parts of the skin, in the
development of the beard, whiskers, and mane. Many
species are colored either in so extraordinary or beautiful

4* 4 The Variation of Animals uml Plants under Domestication,' IMS,
vol. i. pp. 51-64.

*"4Pro(\ Zool. Hoc.' lH«i>, p. 104. Sec, al*o, Dr. llartnmnn, 4 Aim.
d. Undw.' Bd. xliii. s. 222.

292

SEXUAL SELECTION: MAMMALS. [Part II.

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 orna-
ment. The accompanying ligures (Figs. 70 to 74) serve

Fia. 70.— Head of Semnopithccns rublcnndtiB. This and the following figures
(from Prof. Gervaie) are given to nhow the odd arrangement and develop-
ment of the hair on the head.

to show the arrangement of the hair of? the face and head
in several species. It is scarcely conceivable that these
crests of hair and strongly-contrasted colors of the fur
and skin can be the result of mere variability without the
aid of selection ; and it is inconceivable that they can be
of any- ordinary use to these animals. If so, they have
probably been pained through sexual selection, though
transmitted equally, or almost equally, to both sexes.

Chap. XVIII.]

QUADRUMANA.

293

With many of the Quadrumana, we have additional evi-
dence of the action of sexual selection in the greater size
and strength of the males, and in the greater development
of their canine teeth, in comparison with the females.

Fig 71.— Head of Semnopithecus comatus. Fig. 72.— Ileau of Ccbus capuchins.

Fio. 73.— ncad of Atcles marginataB. Fig. 71— Head ofCebui veltenwtta.

With respect to the strange manner in which l > * > i It

sexes of some species are colored, and of (he beauty vf
others, B few instances will Suffice. The lace of the (\r-
COpitheniH pcfaurista (Fig. 7.r>) is black, the whiskers and
beard being white, with a defined, round, while sp<»t on

294

SEXUAL SELECTION : MAMMALS. [Part D.

the nose, eovered with short white hair, which gives to
the animal an almost ludicrous aspect. The Semnopithe-

Fio. 75.— CcrcopithectiB petanri*ta (from Brehm).

Chap. XVIII.] QUADRUMANA.

295

cus frontatus likewise has a blackish face with a long
black beard, and a large naked spot on the forehead of a
bluish-white color. The face of Macacus lasiotus is dirty
flesh-colored, with a defined red spot on each cheek. The
appearance of Cercocebus ^Ethiops is grotesque, with its
black face, white whiskers and collar, chestnut head, and a
large naked white spot over each eyelid. In very many
species, the beard, whiskers, and crests of hair round the
face, are of a different color from the rest of the head,
and, when different, are always of a lighter tint,44 being
often pure white, sometimes bright yellow, or reddish.
The whole face of the South- American Brachyurus calvus
is of a " glowing scarlet hue ; " but this color does not
appear until the animal is nearly mature.45 The naked
skin of the face differs wonderfully in color in the various
species. It is often brown or flesh-color, with parts per-
fectly 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
gray. In all the species known to Mr. Bartlett, in which
the adults of both sexes have strongly-colored faces, the
colors are dull or absent during early youth. This like-
wise holds good with the Mandrill and Rhesus, in which
the face and the posterior parts of the body are brilliantly
colored in one sex alone. In these latter cases we have
every reason to believe that the colors were acquired
through sexual selection; and we are naturally led to
extend the same view to the foregoing species, though

44 I observed this fuct in tho Zoological Gardens; ami numerous
caaeH may he Hccn in tho colored plates in (icoM'roy St. -Milam1 ami V.
Cuviur, 'Hist. Nat. des Mainiinfe-res,' torn. i. IH2-I.

45 Hutos, 'Tin; Naturalist on the Amazons,' 1868, vol. ii. p. ft 10.

296

SEXUAL SELECTION: MAMMALS.

[Part II.

both sexes when adult have their faces colored in the
same manner.

Although, according to our taste, many kinds of mon-
keys are far from beautiful, other species are universally
admired for their elegant appearance and bright colors.
The Semnopithecus 9iemceus1 though peculiarly colored, is
described as extremely pretty ; the orange-tinted face is
surrounded by long whiskers of glossy whiteness, with a
line of chestnut red over the eyebrows ; the fur on the
back is of a delicate gray, with a square patch on the
loins, the tail and the forearms all of a pure white; a
gorget of chestnut surmounts the chest ; the hind-thighs
are black, with the legs chestnut red. I will mention only
two other monkeys on account of their beauty ; and I
have selected these as they present slight sexual differ-
ences in color, which renders it in some degree probable
that both sexes owe their elegant appearance to sexual
selection. In the mustache-monkey (Cercopithecus ce-
phus), the general color of the fur is mottled greenish,
with the throat white; in the male the end of the tail is
chestnut ; but the face is the most ornamented part, the
skin being chiefly bluish-gray, 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 mus-
tache; the whiskers are orange-colored, with the upper
part black, forming a band which extends backward 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, deserv-
edly called Cercopithecus Diana (Fig. 76) ; the general
color of the fur is gray ; the chest and inner surface of
the fore-legs are white ; a large triangular, defined space
on the hinder part of the back is rich chestnut ; in the
male the inner sides of the thighs and the abdomen are
delicate fawn-colored, and the top of the head is black ;

Chap. XVIII.]

SUMMARY.

297

the face and ears are intensely black, finely contrasted
with a white transverse crest over the eyebrows and with

Fig. TO.— CercopithccuB Diana (from Brc-lnn).

a long while peaked beard, of which the basal portion is
black48

40 J have Keen most of the abovc-nauml monkeys in tin- Zoological
Society's GkrdeDI. Th« (1,-sr.iplion of the Sanxopitfttms tunnrus is tuken
from Mr. W. 0. Martin's 'Nut. Hist, of Mammalia,' 1841, p. 460{ IM
alHo pp, 175, r»i»:t.

298 SEXUAL SELECTION: MAMMALS. [Part II.

In these and many other monkeys, the beauty and
singular arrangement of their colors, 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 all been acquired or modified through
that form of selection which I have called sexual selec-
tion. This does not depend on any superiority in the
general struggle for life, but on certain individuals of one
sex, generally the male sex, having been successful in
conquering other males, and on their having left a larger
number of offspring to inherit their superiority, than the
less successful males.

There is another and more peaceful kind of contest,
in which the males endeavor to excite or allure the fe-
males by various charms. This may be effected by the
powerful odors emitted by the males during the breeding-
season ; the odoriferous glands having been acquired
through sexual selection. Whether the same view can
be extended to the voice is doubtful, for the vocal organs
of the males may have been strengthened by use during
maturity, under the powerful excitements of love, jealousy,
or rage, and 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
females, seem in most cases to be merely ornamental,
though they sometimes serve as a defence against rival
males. There is even reason to suspect that the branch

Chap. XVIIL]

SUMMARY.

299

ing horns of stags, and the elegant horns of certain ante-
lopes, though properly serving as weapons of offence or
of defence, have been partly modified for the sake of orna-
ment.

When the male differs in color from the female, he gen-
erally exhibits darker and more strongly-contrasted tints.
We do not in this class meet with the splendid red, blue,
yellow, and green colors, so common with male birds and
many other animals. The naked parts, however, of cer-
tain Quadrumana must be excepted ; for such parts, often
oddly situated, are colored in some species in the most
brilliant manner. The colors of the male in other cases
may be due to simple variation, without the aid of selec-
tion. But when the colors are diversified and strongly-
pronounced, when they are not developed until near ma-
turity, 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 colored in the
same manner, and the colors are conspicuous or curiously
arranged, without being of the least apparent use as a pro-
tection, and especially when they are associated with va-
rious other ornamental appendages, we are led by anal-
ogy to the same conclusion, namely, that they have been
acquired through sexual selection, although transmitted
to both sexes. That conspicuous and diversified colors,
whether confined to the males or common to both sexes,
are as a general rule associated in the same groups and
subgroups with other secondary sexual characters, serv-
ing for war or for ornament, will be found to hold good
if we look back to the various cases given in this and the
last chapter.

The law of the equal transmission of characters to
both sexes, as far as color and other ornaments are con-

300

SEXUAL SELECTION: MAMMALS. [Part II.

cerned, has prevailed far more extensively with mammals
than with birds ; but in regard to weapons, such as horns
and tusks, these have often been transmitted either exclu-
sively, or in a much higher degree, to the males than to
the female. This is a surprising circumstance, for as the
males generally use their weapons as a defence against
enemies of all kinds, these weapons would have been of
service to the females. Their absence in this sex can be
accounted for, as far as we can see, only by the form of
inheritance which has prevailed. Finally, with quadru-
peds the contest between the individuals of the same sex,
whether peaceful or bloody, has with the rarest excep-
tions been confined to the males ; so that these have been
modified through sexual selection, either for fighting with
each other or for alluring the opposite sex, far more com-
monly than the females.

Chap. XIX.] SEXUAL DIFFERENCES.

301

CHAPTER XIX.

Secondary Sexual Characters of Man.

Differences between Man and "Woman. — Causes of such Differences and jf
Certain Characters common to both Sexes. — Law of Battle. — Diher-
ences in Mental Powers — and Voice. — On the Influence of Beauty in
determining the Marriages of Mankind. — Attention paid by Savages
to Ornaments. — Their Ideas of Beauty in Woman. — The Tendency
to exaggerate each Natural Peculiarity.

With mankind the differences between the sexes are
greater than in most species of Quadrumana, but not so
great as in some, for instance, the mandrill. Man on an
average is considerably taller, heavier, and stronger than
woman, with squarer shoulders and more plainly-pro-
nounced muscles. Owing to the relation which exists
between muscular development and the projection of the
brows,1 the superciliary ridge is generally more strongly
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 tribes the women are said,
whether truly I know not, to differ slightly in tint from
the men ; and with Europeans, the women are perhaps
the more brightly-colored of the two, as may bo seen when
both sexes have been equally exposed to the weather.

Man is more courageous, pugnacious, and energetic
than woman, and lias a more inventive genius. His l>r:iin
is absolutely larger, but whether relatively to the larger

1 Sfhuull'liiiuscii, translation iit ' Anthropological Itfviow,' Oct. IHtlN,
pp. 419, 420, f27.

302

SEXUAL SELECTION: MAN. [Part II.

size of his body, in comparison with that of woman, 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 her 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 dis-
tinctive characters of the male sex are not fully developed
until he is nearly mature ; and if emasculated they never
appear. The beard, for instance, is a secondary sexual
character, and male children are beardless, though at an
early age they have abundant hair on their heads. It is
probably due to the rather late appearance in life of the
successive variations, by which man acquired his masculine
characters, that they are transmitted to the male sex alone.
Male and female children resemble each other closely, like
the young of so many other animals in which the adult
sexes differ; they likewise resemble the mature female
much more closely than the mature male. The female, *
however, ultimately assumes certain distinctive characters,
and in the formation of her skull is said to be interme-
diate between the child and the man.' Again, as the young
of closely-allied though distinct species do not differ nearly
so much from each other as do the adults, so it is with
the children of the different races of man. Some have
even maintained that race-differences cannot be detected
in the infantile skull.4 In regard to color, the new-born

* Ecker, translation in 'Anthropological Review,' Oct. 1868, pp. 861-
856. The comparison of the form of the skull, in men and women has
•been followed out with much care by Welcker.

1 Ecker and Welcker, ibid. pp. 852, 856 ; Vogt, 1 Lectures on Man.
Eng. trauslat. p. 81.

4 Schaaffhausen, ' Anthropolog. Review,' ibid. p. 429.

Chap. XIX.]

SEXUAL DIFFERENCES.

303

negro child is reddish nut-brown, which soon becomes
slaty-gray ; the black color 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 chest-
nut-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 yellow-
ish-brown tint of their parents. Similar observations have
been made in other parts of America.5

I have specified the foregoing familiar differences be-
tween the male and female sex in mankind, because they
are curiously the same as in the Quadrumana. With
these animals the female is mature at an earlier age than
the male ; at least this is certainly the case%ith the Cebus
azarce.* With most of the species the males are larger
and much stronger than the females, of which fact the
gorilla offers 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 fe-
males,7 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 sim-

6 Pruner-Bey, on negro infants, as quoted by Vogt, 'Lectures on
Man,' Eng. translat. 1864, p. 189 : for further facts on negro infants, as
quoted from Winterbottom and Camper, see Lawrence, ' Lectures on
Physiology,' etc. 1822, p. 451. For the infants of the Guaranys, see
Rengger, 1 Siiugethierc,' etc. s. 8. See also Godron, ' I)c 1'EspiVe,' torn,
ii. 18R9, p. 253. For the Australians, Waitz, 1 Introdurt. to Aiitlirop.d-
ogy,' Eng. translat. 18M, p. 99.

' Rengger, ' Slogtthiere,1 etc. 1830, s. 49.

' As in Macanut njntnnohjua ( Desinarest, ' Mummalogic,' p. 6f») and in

tfylobat* agilU (Geoffroj Bt-HOaire and r. Ourier, 'Hist. Nut. des

Malum.' 1824, turn. i. p. 'J).

304

SEXUAL SELECTION: MAN.

[Part II

ilar difference between the two sexes in the Australians.
With monkeys, when there is any difference in the voice,
that of the male is more powerful. We have seen tliat
certain male monkeys have a well-developed heard, which
is quite deficient, or much less developed, in the female.
No instance is known of the beard, whiskers, or mustache
being larger in a female than in the male monkey. Even
in the color of the beard there is a curious parallelism
between man and the Quadrumana, for when in man the
beard differs in color from the hair of the head, as is often
the case, it is, I believe, invariably of a lighter tint, being
often reddish. I have observed this fact in England, and
Dr. Hooker, who attended to this little point for me in
Russia, found no exception to the rule. In Calcutta, Mr
J. Scott, of the Botanic Gardens, was so kind as to ob-
serve with car? the many races of men to be seen there, as
well as in some other parts of India, namely, two races in
Sikhira, the Bhoteas, Hindoos, Burmese, and Chinese.
Although most of these races have very little hair on the
face, yet he always found that when there was any differ-
ence in color between the hair of the head and the beard,
the latter was invariably of a lighter tint. Now with
monkeys, as has already been stated, the beard frequently
differs in a striking manner in color from the hair of the
head, and in such cases it is invariably of a lighter hue,
being often pure white, sometimes yellow or reddish.9

8 1 Anthropological Review,' Oct. 1868, p. 353.

• Mr. Blyth informs me that he has never seen more than one instance
<jf the beard, whiskers, etc., in a monkey becoming white with old age,
as is so commonly the case with us. This, however, occurred in an aged
and confined Macacus cynomolgus, whose mustaches were "remarkably
long and human-like." Altogether this old monkey presented a ludicrous
resemblance to one of the reigning monarchs of Europe, after whom he
was universally nicknamed. In certain races of man the hair on the
head hardly ever becomes gray ; thus Mr. D. Forbes has never seen, as

Chap. XIX.] SEXUAL DIFFERENCES. 305

In regard to the general hairiness of the body, the wom-
en 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.10 Lastly, male mon-
keys, 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 be-
tween the sexual differences, of man and the Quadrumana.
With some few species, however, as with certain baboons,
the gorilla, and orang, there is a considerably greater dif-
ference between the sexes, in the size of the canine teeth,
in the development and color of the hair, and especially in
the color of the naked parts of the skin, than in the case
of mankind.*

The secondary sexual characters of man are all highly
variable, even within the limits of the same race or sub-
species ; and they differ much in the several races. These
two rules generally hold good throughout the animal
kingdom. In the excellent observations made on board
the JVovara, 11 the male Australians were found to exceed
the females by only sixty-five millimetres in height, while
with the Javanese the average excess was two hundred
and eighteen millimetres, so that in this latter race the dif-
ference in height between the sexes is more than thrice
as great as with the Australians. The numerous measure-
ments of various other races, with respect to stature, the
circumference of the neck and chest, and the Length of the
backbone and arms, which were carefully made, marly all

ho informs me, an instance with the Aymaras and Quichuas of South
America.

10 This is the case with the females of several species of Hvlobates,
Bee Geofl'roy St.-Hilaire and V. Cuvier, 'Hist. Nat. des Matnm.' torn. i.
See, also, on If. lar. 1 Penny Encyclopedia,' vol. ii. pp. 1 •!'.», lf>0.

11 The results were; deduced by Dr. Wcisbach from the measurements
made by Drs. K. Scherzcr and Schwarz, see ' Keise der Novara: At thro-
polog Theil.' 1H«7, H. 216, 231, 2.TI, 1»:P.». 2M.

306

SEXUAL SELECTION: MAN.

[Part II.

showed that the males differed much more from each other
than did the females. This fact indicates that, as far as
these characters are concerned, it is the male which has
been chiefly modified, since the races diverged from their
common and primeval source.

The development of the beard and the hairiness of the
body differ remarkably in the men belonging to distinct
races, and even to different families in the same race. We
Europeans see this among ourselves. In the island of St.
Kilda, according to Martin,19 the men do not acquire
beards, which are very thin, until the age of thirty or
upward. On the Europseo- Asiatic Continent, beards pre-
vail until we pass beyond India, though with the natives
of Ceylon they are frequently absent, as wa$ noticed in
ancient times by Diodorus.1' Beyond India beards dis-
appear, as with the Siamese, Malays, Calmucks, Chinese,
and Japanese; nevertheless the Ainos, 14 who inhabit the
northernmost islands of the Japan archipelago, are the
most hairy men in the world. With negroes the beard is
scanty or absent, and they have no whiskers; in both
sexes the body is 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, while those of the

18 'Voyage to St. Kilda' (3d edit. 1753), p. 87.

18 Sir J. E. Tennent, 'Ceylon,' vol. ii. 1859, p. 107.

u Quatrefages, * Revue des Cours Scientifiques,' Aug. 29, 1868, p.
680 ; Vogt, ' Lectures on Man,' Eng. translat. p. 127.

18 On the beards of negroes, Vogt, 'Lectures,' etc. ibid. p. 127;
Waitz, 'Introduct. to Anthropology,' Engl, translat. 1863, vol. i. p. 96.
It is remarkable that in the United States ('Investigations in Military
and Anthropological Statistics of American Soldiers,' 1869, p. 569) the
pure negroes and their crossed offspring seem to have bodies almost as
hairy as those of Europeans.

'« Wallace, « The Malay Arch.' vol. ii. 1869, p. 178.

Chap. XIX.] SEXUAL DIFFERENCES.

307

not-distant archipelagoes of Tonga and Samoa are beard-
less ; but these men belong to distinct races. In the Ellice
group all the inhabitants belong to the same race ; yet on
one island alone, namely, Nunemaya, "the men have splen-
did beards ; " while on the other islands " they have, as a
rule, a dozen straggling hairs for a beard." 17

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 during
old age. With the tribes of North America, Catlin esti-
mates that eighteen out of twenty men are completely des-
titute by nature of a beard ; but occasionally there may
be seen a man, who has neglected to pluck out the hairs at
puberty, with a soft beard an inch or two in length. The
Guaranys of Paraguay differ from all the surrounding
tribes in having a small beard, and even some hair on the
body, but no whiskers.18 I am informed by Mr. D.
Forbes, who particularly attended to this subject, that the
Aymaras and Quichuas of the Cordillera are remarkably
hairless, yet in old age a few straggling hairs occasionally
appear on the chin. The men of these two tribes have
very little hair on the various parts of the body where
hair grows abundantly in Europeans, and the women have
none on the corresponding parts. The hair on the head,
however, attains an extraordinary length in both sexes,
often reaching almost to the ground ; and this is likewise
the case with some of the North American tribes. In the
amount of* hair, and in the general shape of the body, the
sexes of the American aborigines do not differ from each
other so much as with most other races ortnankind.19 This

11 Dr. J. Burnard Davis on Oceanic Races, in ' Anthropolog. Review,1
April, 1870, pp. 185, 191.

18 Catlin, 'North American Indians,' 3d edit. 1812, vol. ii. p. '227. Ofl
the Guaranys, see A/.ara, 1 Voyages dans rAmcriquc Morid.' torn. ii.
1809, p. f>8 ; also Render, 4 Siiu^-thu're von Paraguay,' s.

19 Prof, and Mrs. Agassi/. (' Journey in Hra/.il,' p. 580) remark that

308

SEXUAL SELECTION: MAN.

[Pabt II.

fact is analogous with what occurs with some allied mon-
keys ; thus the sexes of the chimpanzee are not as different
as those of the gorilla or orang.30

In the previous chapters we have seen that with mam-
mals, birds, fishes, insects, etc., many characters, which
there is every reason to believe were primarily gained
through sexual selection by one sex alone, have been trans-
ferred to both sexes. As this same form of transmission
has apparently prevailed to a large extent with mankind,
it will save much useless repetition if we consider the
characters peculiar to the male sex together with certain
other characters common to both sexes.

Law of Battle. — With barbarous nations, for instance
with the Australians, the women are the constant cause of
war both between the individuals of the same tribe and
between distinct tribes. So no doubt it was in ancient
times ; " nam fuit ante Helenam mulier teterrima belli
causa." With the North American Indians, the contest
is reduced to a system. That excellent observer, Heanie,"
says : " It. has ever been the custom among these people
for the men to wrestle for any woman to whom they are
attached ; and, of course, the strongest party always car-
ries off the prize. A weak man, unless he be a good hunt-
er, and well-beloved, is seldom permitted to keep a wife
that a stronger man thinks worth his notice. This custom
prevails throughout all the tribes, and causes a great spirit
of emulation among their youth, who are upon all oc-

the sexes of the Ame^jcan Indians differ less than those of the negroes
and of the higher races. See also Rengger, ibid. p. 3, on the Guaranys.

*° Riitimeyer, 1 Die Grenzen der Thierwelt ; eine Betrachtung zu Dar-
win's Lehre,' 1868, 8. 54.

11 *A Journey from Prince of Wales Fort,' 8vo edit. Dublin, 1706,
p. 104. Sir J. Lubbock ('Origin of Civilization,' 1870, p. 69) gives other
and similar cases in North America. For the Guanas of South America
see Azara, 1 Voyages,' etc., torn. ii. p. 94.

Chap. XIX.]

LAW OF BATTLE.

309

casions, 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 or more
years old, as before that age they cannot conquer their ri-
vals.

Other similar facts could be given ; but even if we had
no evidence on this head, we might feel almost sure, from
the analogy of the higher Quadrumana,23 that the law of
battle had prevailed with man during the early stages of
his development. The occasional appearance at the pres-
ent day of canine teeth which project above the others,
with traces of a diastema or open space for the reception
of the opposite canines, is in all probability a case of re-
version 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 become reduced throng!)
disuse, as would the teeth, through the not well understood
principles of correlation and the ec onomy of growth ; for
we everywhere see that parts which are no longer of ser-
vice are reduced in size. By such steps the original in-
equality between the jaws and teeth in the two sexes of
mankind would ultimately have been quite obliterated. The
case is almost parallel with that of many male Ruminants,
in which the canine teeth have been reduced to mere rudi-
ments, or have disa pptarc< 1, apparently in consequence of
the development of horns. As the prodigious difference
between the skulls of the two sexes in the Gorilla and

"On tho lighting of the male gorilla, nee I>r. Savage, in 'Huston
Journal Of Nat. H'ih.' vol. V. 1 817, p. 4'2.'l. <>n I'rrg/n/tu cn((lluat see
the 4 Indian Field,' iH.V.t, p, 146.

310

SEXUAL SELECTION : MAN. [Part II.

Orang 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 pro-
genitors of man led to a most striking and favoraMr

change in his appearanoe^^

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, rug-
ged outline of body, his greater courage and pugnacity,
are all due in chief part to inheritance from some early
male progenitor, who, like the existing anthropoid apes,
was thus characterised. These characters will, however
have been preserved or even augmented during the long
ages while man was still in a barbarous condition, by the
strongest and boldest men having succeeded best in the
general struggle for life, as well as in securing wives, and
thus having left a large number of offspring. 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 an-
compelled to work at least as hard as the men. With
civilized people the arbitrament of battle for the posses-
sion 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 mutual 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 very important part. I am aware that some writers
doubt whether there is any inherent difference ; but this
is at least probable from the analogy of the lower animals
which present other secondary sexual characters. No one

Chap. XIX.] MENTAL POWERS OF MAN AND WOMAN. 311

will dispute that the bull differs in disposition from the
cow, the wild-boar from the sow, the stallion from the
mare, and, as is well known to the keepers of menageries,
the males of the larger apes from the females. Woman
seems to differ from man in mental disposition, chiefly in
her greater tenderness and less selfishness ; and this holds
good even with savages, as shown by a well-known pas-
sage in Mungo Park's Travels, and by statements made
by many other travellers. Woman, owing to her maternal
instincts, displays these qualities toward her infants in an
eminent degree ; therefore it is likely that she should often
extend them toward her fellow-creatures. Man is the ri-
val 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 unfortu-
nate birthright. It is generally admitted that with woman
the powers of intuition, of rapid perception, and perhaps
of imitation, are more strongly marked than in man ; but
some, at least, of these faculties are characteristic of the
lower races, and therefore of a past and lower state of
civilization.

The chief distinction in the intellectual powers of the
two sexes is shown by man attaining to a higher emi-
nence, in whatever he takes up, than woman can attain —
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 — comprising composi-
tion 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 of averages, so well illustrated
by Mr. Gftlton, in his work on 4k Hereditary (tcnius," that
if men are capable of decided eminence over women in

312

SEXUAL SELECTION : MAN. [Pakt II.

many subjects, the average standard of mental power in
man must be above that of woman.

The half-human male progenitors of man, and men in a
savage state, have struggled together during many gener-
ations for the possession of the females. But mere bodily
strength and size would do little for victory, unless asso-
ciated 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 man, 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 invent and fashion weapons, requires the aid of the
higher mental faculties, namely, observation, reason, in-
vention, or imagination. These various faculties will thus
have been continually put to the test, and selected during
manhood ; they will, moreover, have been strengthened
by use during this same period of life. Consequently, in
accordance with the principle often alluded to, we might
expect that they would at least tend to be transmitted
chiefly to the male offspring at the corresponding period
of manhood.

Now, when two men are put into competition, or a
man with a woman, who possess every mental quality in
the same perfection, with the exception that the" one has
higher energy, perseverance, and courage, this one will
generally become more eminent, whatever the object may
be, and will gain the victory." He may be said to possess
genius — for genius has been declared by a great authority

83 J. Stuart Mill remarks ('The Subjection of Women,' 1869, p. 122),
'The things in which man most excels woman are those which require
most plodding, and long hammering at single thoughts." What is this
but energy and perseverance ?

Chap. XIX.] MENTAL POWERS OF MAN AND WOMAN. 313

to be patience ; and patience, in this sense, means unflinch-
ing, undaunted perseverance. But this view of genius is
perhaps deficient ; for without the higher powers of the
imagination and reason, no eminent success in many sub-
jects can be gained. But these latter as well as the for-
mer faculties 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 thus gained will have been transmitted
more fully to the male than to the female offspring. Thus
man has ultimately become superior to woman. It is,
indeed, fortunate that the law of the equal transmission
of characters to both sexes has commonly prevailed
throughout the whole class of mammals ; otherwise it is
probable that man would have become as superior in
mental endowment to woman, as the peacock is in orna-
mental plumage to the peahen.

It must be borne in mind that the tendency in charac-
ters acquired at a late period of life by either sex, to be
transmitted to the same sex at the same age, and of char-
acters acquired at an early age to be transmitted to both
sexes, are rules which, though general, do not always hold
good. If they always held good, we might conclude (but
I am here wandering beyond my proper bounds) that the
•inherited effects of the early education of boys and girls
would be transmitted equally to both 66X68 ; so that the
present inequality between the sexes in mental power
could 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 (lie same
standard as man, she ought, when nearly adult, to hv
trained to energy and perseverance, and to have her rea-
son and imaginat ion exercised to the highest point; and
88

3U

SEXUAL SELECTION: MAN.

[Part IL

then she would probably transmit these qualities chiefly
to her adult daughters. The whole body of women, how-
ever, could not be thus raised, unless during many genera-
tions the women who excelled in the above robust virtues
were married, and produced offspring in larger numbers
than other women. As before remarked with respect to
bodily strength, although men do not now fight for tho
sake of obtaining wives, and this form of selection has
passed away, yet they generally have to undergo, during
manhood, a severe struggle in order to maintain them-
selves and their families ; and this will tend to keep up or
even increase their mental powers, and, as a consequence,
the present inequality between the sexes."*

Voice and Musical Powers. — In some species of Quad-
rumana there is a great difference between the adult sexes,
in the power of the voice and in the development of tho
vocal organs ; and man appears to have inherited this dif-
ference from his early progenitors. His vocal cords arc
about one-third longer than in woman, or than in boys ;
and emasculation produces the same effect on him as on
the lower animals, for it "arrests that prominent growth
of the thyroid, etc., which accompanies the elongation of
the cords." " "With respect to the cause of this difference
between the sexes, I have nothing to add to tho remarks
made in the last chapter on the probable effects of the
long-continued use of the vocal organs by the male under
the excitement of love, rage, and jealousy. According

M An observation by Yogt bears on this subject : be bats, it is a " re-
markable circumstance, that the difference between the sexes, as regards
the cranial cavity, increases with the development of the race, so that tho
male European excels much more the female, than the negro the negress.
Wclckcr confirms this statement of Huschkc from his measurements of
negro and German skulls." But Vogt admits (' Lectures on Man,' Eng.
translat. 1864, p. 81) that more observations are requisite on this point.

* Owen, 1 Anatomy of Vertebrates,' vol. iii. p. 603.

Chap. XIX.]

MUSICAL TOWERS.

315

to Sir Duncan Gibb,28 the voice differs in the different
races of mankind; and with the natives of Tartary,
China, etc., the voice of the male is said not to differ so
much from that of the female, as in most other races.

The capacity and love for singing or music, though
not a sexual character in man, must not here be passed
over. Although the sounds emitted by animals of all
kinds serve many purposes, a strong case can be made
out, that the vocal organs were primarily used and per-
fected in relation to the propagation of the species. In-
sects 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 alone. The
sounds thus produced consist, I believe in all cases, of the
same note, repeated rhythmically;27 and this is sometimes
pleasing even to the ears of man. Their chief, and in
some cases exclusive use appears to be either to call or to
charm the opposite sex.

The sounds produced by fishes are said in some cases
to be made only by the males during the breeding-season.
All the air-breathing Vertebrata necessarily possess an
apparatus for inhaling and expelling air, with a pipe capa-
ble of being closed at one end. Hence when the primeval
members of this class were strongly excited and their
muscles violently contracted, purposeless sounds would
almost certainly have been produced ; .and these, if they
proved in any way serviceable, might readily have been
modified or Intensified by the preservation of properly-
adapted variations. The Amphibians are the lowest Ver-
tebrates which breathe air; and many of these animals,
namely, frogs and toads, possess vocal organs, which are

« Journal of Hi.- Antlm.pnl..- Soc.' April, lHflD, pp. Mi., h\i.
M Dr. ScinMcr, "Note* on Stri.lulution," in True. Hu^toli S'O. ».f
Nut. lliMt.' vol. d. April, 1968,

316

SEXUAL SELECTION: MAN.

[Part II.

incessantly used during 'the breeding-season, and which
are often more highly developed in the male than in the
female. The male alone of the tortoise utters a noise, and
this only during the season of love. Male alligators roar
or bellow during the same season. Every one knows how
largely birds use their vocal organs as a means of court-
ship ; and some species likewise perform what may be
called instrumental music.

In the class of Mammals, with which we arc here more
particularly concerned, the males of almost all the species
use their voices during the breeding-season much more
than at any other time ; and some are absolutely mute
excepting at this season. Both sexes of other species, or
the females alone, use their voices as a love-call. Con-
sidering these facts, and that the vocal organs of some
quadrupeds are much more largely developed in the male
than in the female, either permanently or temporarily
during the breeding season ; and considering that in most
of the lower classes the sounds produced by the males,
serve not only to call but to excite or allure the female, it
is a surprising fact that we have not as yet any good evi-
dence that these organs are used by male mammals to
charm the females. The American Mycetes caraya per-
haps forms an exception, as does more probably one or
those apes which come nearer to man, namely, the Ilylo-
bates agilis. This gibbon has an extremely loud but mu-
sical voice. Mr. Waterhouse states," " It appeared to me
that in ascending and descending the scale, the intervals
were always exactly half-tones ; and I am sure that the
highest note was the exact octave to the lowest. The
quality of the notes is very musical ; and I do not doubt
that a good violinist would be able to give a correct idea

*• Given in W. C. L. Martin's 1 General Introduct. to Nat. Ilist. of
Mamm. Animals,' 1841, p. 432 ; Owen, 1 Anatomy of Vertebrates,' vol. iii.
p. 600.

^HAP. XIX.]

MUSICAL POWERS.

317

i the gibbon's composition, excepting as regards its
mdness." Mr. Waterhouse then gives the notes. Prof,
'wen, who is likewise a musician, confirms the foregoing
.atement, and remarks that this gibbon " alone of brute
mammals may be said to sing." It appears to be much
excited after its performance. Unfortunately, its habits
have never been closely observed in a state of nature ; but
from the analogy of almost all other animals, it is highly
probable that it utters its musical notes especially during
the season of courtship.

The perception, if not the enjoyment, of musical ca-
iences and of rhythm is probably common to all animals,
ind no doubt depends on the common physiological nature
of their nervous systems. Even Crustaceans, which are
not capable of producing any voluntary sound, possess
certain auditory hairs, which have been seen to vibrate
when the proper musical notes are struck." It is well
known that some dogs howl when hearing particular 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." 30 With
all those animals, namely insects, amphibians, and birds,
the males of which during the season of courtship inces-
santly produce musical notes or mere rhythmical sounds,
we must believe that the females arc able to appreciate
them, and are thus excited <>r charmed; otherwise the
incessant efforts of the males and the complex struct area
often possessed exclusively by them would be useless.

With man song is generally admitted to be the basis
or origin of instrumental music. As neither the enjoy-
ment nor the capacity of producing musical notes are
faculties of the least direct use to man in reference to his
ordinary habits of life, they must be ranked among the

89 Helmholts, 'Thlorle Fhyi. <1«> In Muslqae,' 1868, p. l S7.
«° Mr. if. Brows, 'm ' Troc. ZooL Boo.' 1888, i>. no.

318

SEXUAL SELECTION: MAX. [Tart"

most mysterious with which he is endowed. They .
present, though in a very rude and as it appears alm«
latent condition, in men of all races, even the most savn~ •
but so different is the taste of the different races, that
music gives not the least pleasure to savages, and thfe
music is to us hideous and unmeaning. Dr. Socman, in
some interesting remarks on this subject," " doubts
whether even among the nations of Western Europe, inti-
mately connected as they are by close and frequent inter-
course, the music of the one is interpreted in the HUM MM
by the others. By travelling eastward we find thai tlr
is certainly a different language of music. Songs of j<
and dance-accompaniments arc no longer, as with us, ;
the major keys, but always in the minor." Whether i
not the half-human progenitors of man possessed, like th
before-mentioned gibbon, the capacity of producing, and
no doubt of appreciating, musical notes, we have every
reason to believe that man possessed these faculties at a
very remote period, for singing and music are extremely
ancient arts. Poetry, which may be considered as the
offspring of song, is likewise so ancient that many persons
have felt astonishment that it should have arisen during
the earliest ages of winch we have any record.

The musical faculties, which are not wholly <1< hY nt
in any race, are capable of prompt and high development,
as we sec with Hottentots and Negroes, who have readily
become excellent musicians, although they do not praetise
in their native countries any thing that we should esteem
as music. But there is nothing anomalous in this circum-
stance : some species of birds which never naturally sing,
can without much difficulty be taught to perform ; thus

81 4 Journal of Anthropolog. Soc' Oct. 1870, p. civ. Sec aIso the I
eral later chapters in Sir John Lubbock's 'Prehistoric Times,' f
edition, 18G0, w hich contains an admirable account of the hi bits c
ages.

I AP. XIX.]

MUSICAL POWERS.

319

of 3 house-sparrow has learned the song of a linnet. As
lc 3se two species are closely allied, and belong to the
0 "'er of Insessores, which includes nearly all the singlng-
st ds in the world, it is quite possible or probable that a
progenitor of the sparrow may have been a songster. It
is a much more remarkable fact that parrots, which belong
to a group distinct from the Insessores, and have differ-
ently-constructed vocal organs, can be taught not only to
speak, but to pipe or whistle tunes invented by man, so

i ^hat they must have some musical capacity. Nevertheless
would be extremely rash to assume that parrots are
descended from some ancient progenitor which was a
i^ngster. Many analogous cases could be advanced of
i;ans and instincts originally adapted for one purpose,
laving been utilized for some quite distinct purpose.32

i Hence the capacity for high musical development, which
the savage races of man possess, may be due either to our
semi-human progenitors having practised some rude form
of music, or simply to their having acquired for some dis-
tinct purposes the proper vocal organs. But in this latter
case we must assume that they already possessed, as in
the above instance of the parrots, and as seems to occur
with many animals, some sense of melody.

Music affects every emotion, but docs not by itself ex-
cite in us the more terrible emotions of horror, ra<jrc, etc.
It awakens the gentler feelings of tenderness and love,

83 Since this chapter has been printed I have seen a valuable article
by Mr. Chaunccy Wright (' North Amcr. Review,' Oct. 1870, p. 293),
who, iu discussiug the above subject, remarks: " There are many conse-
quences of tho ultimate laws or uniformities of Nature through whiofa
the acquisition of one useful power will bring with it many resulting ad*
vantn^es as well as limiting disadvantages, actual or possible, which the
•inciplo of utility may not have comprehended in in action." This
c pJple has an important bearing, as 1 have attempt, -d to show in tho
1 chapter of this work, on the aoquUitiOO bj B1U Of MUM of his
tal characteristics.

320

SEXUAL SELECTION" : MAN.

[Part II.

which readily pass into devotion. It likewise stirs up in
us the sensation of triumph and the glorious ardor iW
war. These powerful and mingled feelings may well give
rise to the sense of sublimity. "We can concentrate, as
Dr. Seemann observes, greater intensity of feeling in a
single musical note than in pages of writing. Nearly
the same emotions, but much weaker and less complex,
are probably felt by birds when the male pours forth his
full volume of song, in rivalry with other males, for the
sake of captivating the female. Love is still the com-
monest theme of our own songs. As Herbert Spencer
remarks, music " arouses dormant sentiments of which
had not conceived the possibility, and do not know i
meaning ; or, as Richter says, tell us of things we h:i\ e
not seen and shall not see." " Conversely, when vivid
emotions are felt and expressed by the orator or even in
common speech, musical cadences and rhythm are instinc-
tively used. Monkeys also express strong feelings in dif-
ferent tones — anger and impatience by low — fear and
pain by high notes." The sensations and ideas excited in
us by music, or by the cadences of impassioned oratory,

M See the very interesting discussion on the Origin and Function of
Music, by Mr. Herbert Spencer, in bis collected 'Essays,' 1858, p 35°
Mr. Spencer comes to an exactly opposite conclusion to that at which
have arrived. lie concludes that the cadences used in emotional speech
aflbrd the foundation from which music has been developed ; while I
conclude that musical notes and rhythm were first acquired by the male
or female progenitors of mankind for the sake of charming the opposite
sex. Thus musical tones became firmly associated with some of the
strongest passions an animal is capable of feeling, and are consequently
used instinctively, or through association, when strong emotions are ex-
pressed in speech. Mr. Spencer does not offer any satisfactory explana-
tion, nor can I, why high or deep notes should be expressive, both with
man and the lower animals, of certain emotions. Mr. Spencer gives also
an interesting discussion on the relations between poetry, recitative, and
song.

u Renggcr, 1 Siiugcthicrc von Paraguay,' s. 49.

Chap. XIX.]

MUSICAL POWERS.

321

appear from their vagueness, yet depth, like mental re-
jrsions to the emotions and thoughts of a long-past age.
All these facts with respect to music become to a cer-
tain extent intelligible if we may assume that musical
tones and rhythm were used by the half-human progeni-
tors of man, during the season of courtship, when animals
of all kinds are excited by the strongest passions. In
this case, from the deeply-laid principle of inherited asso-
ciations, musical tones would be likely to excite in us, in
a vague and indefinite manner, the strong emotions of a
1c>ng-past age. Bearing in mind that the males of some
lrumanous animals have their vocal organs much
A^v>re developed than in the females, and that one anthro-
pomorphous species pours forth a whole octave of musical
notes and may be said to sing, the suspicion does not ap-
pear improbable that the progenitors of man, either the
males or females, or both sexes, before they had acquired
the power of expressing their mutual love in articulate
language, endeavored to charm each other with musical
notes and rhythm. So little is known about the use of
he voice by the Quadrumana during the season of love,
hat we have hardly any means of judging whether the
bit of singing was first acquired by the male or female
^genitors of mankind. 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 the pro-
genitors of man had become sufficiently human to treat
and value their women merely as useful slaves. The im-
passioned orator, bard, or musician, when with his varied
tones and cadences he excites the Strongest emotions in
his bearers, little suspects that he uses the same means by

>s Se<« un intcrt'sliiiK di-neVmn on this Hulijt i t l»\ Iluokcl, ' Ucnorolle
Murph.' B. ii. 1860, h. 246.

322

SEXUAL SELECTION: MAN.

[Part II.

which, at an extremely remote period, his half-human
cestors aroused each other's ardent passions, during i
mutual courtship and rivalry.

On the Influence of Beauty in determining the Mar-
riages of Mankind. — In civilized life man is largely, but
by no means exclusively, influenced in the choice of his
wife by external appearance; but we are chiefly con-
cerned with primeval times, and our only means of form-
ing a judgment on this subject is to study the habits of
existing semi-civilized and savage nations. If it can be
shown that the men of different races prefer women hav-
ing certain characteristics, or conversely that the women
prefer certain men, we have then to inquire whether such
choice, continued during many generations, would pro-
duce any sensible effect on the race, either on one sex on
both sexes; this latter circumstance depending on the
form of inheritance which prevails.

It will be well first to show in some detail that sav-
ages pay the greatest attention to their personal appear-
ance.89 That they have a passion for ornament is notori-
ous ; and an English philosopher goes so far as to main-
tain that clothes were first made for ornament and not for
warmth. As Prof. Waitz remarks, "however poor and
miserable man is, he finds a pleasure in adorning himself."

36 A full and excellent account of the manner in which savages in all
parts of the world ornament themselves is given by the Italian traveller,
Prof. Mantegazza, 'Rio de la Plata, Viaggi e Studi,' 18G7, pp. 525-545;
all the following statements, when other references are not given, arc
taken from this work. Sec, also, Waitz, 'Introduct. to Anthropolog.'
Eng. transL vol. i. 1863, p. 275, et passim. Lawrence also gives very
full details in his 4 Lectures on Physiology,' 1822. Since this chapter
was written, Sir J. Lubbock has published his 'Origin of Civilization,'
1870, iu which there is an interesting chapter on the present subject,
and from which (pp. 42, 48) I have taken some facts about savages dye-
ing their teeth and hair, and piercing their teeth.

Chap. XIX.]

LOVE OF ORNAMENTS.

323

^he extravagance of the naked Indians of South America
rCecorating themselves is shown " by a man of large
ature gaining with difficulty enough by the labor of a
fortnight to procure in exchange the chica necessary to
paint himself red." 37 The ancient barbarians of Europe
during the Reindeer period brought to their caves any
brilliant or singular objects which they happened to find.
Savages at the present day everywhere deck themselves
with plumes, necklaces, armlets, ear-rings, etc. They
paint themselves in the most diversified manner. " If
painted nations," as Humboldt observes, " had been ex-
amined with the same attention as clothed nations, it
would have been perceived that the most fertile imagina-
tion and the most mutable caprice have created the fash-
ions of painting, as well as those of garments."

In one part of Africa the eyelids are colored black ;
in another the nails are colored yellow or purple. In
many places the hair is dyed of various tints. In different
countries the teeth are stained black, red, blue, etc., and in
the Malay archipelago it is thought shameful to have
white teeth like those of a dog. Not one great country
can be named, from the Polar regions in the north to New
Zealand in the south, in which the aborigines do not tattoo
themselves. This practice was followed by the Jews of
old and by the ancient Britons. In Africa some of the
natives tattoo themselves, but it is much more common to
raise protuberances by rubbing salt into incisions made in
various parts of the body ; and these are considered by the
inhabitants of Kordofan and Darfur "to be great personal
attractions." In the Arab countries no beauty can be
perfect until the cheeks "or temples have been gashed*?' 11

87 Uumboltlt, « Pt>rsoii:il Narrative,' Kn£. tnmslat. vol. iv. ]>. 515; on

the Imagination shown in painting the body, p. 522; <>n modifying the
form of the calf of (lie lejj, p. It',*;.

M(The Nile Tributaries,' 1MC>7; 'The Albert N'yan/.a,' lSCC, vol i.
p. 218.

324

SEXUAL SELECTION: MAN.

[Part II.

In South America, as Humboldt remarks, " a mother
would he accused of culpable indifference toward her chil-
dren, 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 World the shape of the skull was formerly
modified during infancy in the most extraordinary man-
ner, as is still the case in many places, and such deformi-
ties 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 coun-
tries ; it is allowed to grow to full length, so as to reach
the ground, or is combed into " a compact frizzled mop,
which is the Papuan's pride and glory." 40 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 are eradicated. The natives of the
Upper Nile knock out the four front teeth, saying that
they do not wish to resemble brutes. Further south, the
Batokas knock out the two upper incisors, which, as Liv-
ingstone 41 remarks, gives the face a hideous appearance,
owing to the growth of the lower jaw ; but these people
think the presence of the incisors most unsightly, and on
beholding some Europeans, cried out, " Look at the great
teeth ! " The great chief Sebituani tried in vain to alter
this fashion. In various parts of Africa and in the Malay
Archipelago the natives file the incisor teeth into points
like those of a saw, or pierce them with holes, into which
they insert studs.

39 Quoted by IYichard, ' Tbya. Hist, of Mankind.' 4th edit. vol. L
1851, p. 321.

*° On the Papuans, Wallace, 'The Malay Archipelago,' vol. 0. p. 445.
On the coiffure of the Africans, Sir S. Baker, 'The Albert N'yanza,' voL
L p. 210.

*i 1 Travels,' p. 833.

Chap. XIX.]

LOVE OF ORNAMENTS.

325

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, with rings, sticks, feathers,
and other ornaments, inserted into the holes. The ears
are everywhere pierced and similarly ornamented, and
with the Botocudos and Lenguas of South America the
hole is gradually so much enlarged that the lower edge
touches the shoulder. In North and South America and
in Africa either the upper or lower lip is pierced ; and
with the Botocudos the hole in the lower lip is so large
that a disk 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 ex-
cited, when he sold his tembeta — the large colored piece
of wood which is passed through the hole. In Central
Africa the women perforate the lower lip and wear a crys-
tal, which, from the movement of the tongue, has "a
wriggling motion indescribably ludicrous during conver-
sation." The " wife of the chief of Latooka told Sir S. Ba-
ker 49 that his wife 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." Far-
ther south with the Makalolo, the upper lip is perforated,
and a large metal and bamboo ring, called a pelele, is worn
in the hole. " This caused the lip in one case to project
two inches beyond the tip of the nose; and when the lady
smiled the contraction of the muscles elevated it over the
ejet. 'Why do women wear these tilings?' the venera-
ble chief, Chinsurdi, was asked. Evidently surprised at
such a stupid question, he replied, ' For beaut y ! They aro
the only beautiful things women have*; nu n have beards,
women have none. What kind of a person would she bo

49 'The albert N'yan/n,' 1866, vol L i>. j 1 7.

326

SEXUAL SELECTION: MAN.

[Part IL

without the pelele ? She would not be a woman at all
with a mouth like a man, but no beard.' " 43

Hardly any part of the body, which can be unnaturally
modified, has escaped. The amount of suffering thus
caused must have been wonderfully great, 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 n rikc
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 dis-
tinguish the tribes. As with savages the same fashions
prevail for long periods, 44 mutilations, from what* rtf
cause first made, soon come to be valued as distinctive
marks. But self-adornment, vanity, and the admiration
of others, seem to be the commonest motives. In regard
to tattooing, I was told by the missionaries in New Zea-
land, that when they tried to persuade some girls to give
up the practice, they answered, "We must just have ,i E v
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 46 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 irresisti-
ble attractions. 48 In most, but not all parts of the worl 1.
the men are more highly ornamented than the worn. t.

43 Livingstone, '1' ar Association,' 1860; report given in the
'Athcnrcum,' July 7, lb\,?-jntic?9.

44 Sir S. Baker (ibid. vol. i. "p. 210), speaking of the natives of Cei> ral
Africa, says, " Every tribe has a distinct and unchanging fashion lor
dressing the hair." See Agassiz (' Journey in Brazil,' 1808, p. 318; on
the invariability of the tattooing of the Amazonian Indians.

45 Rev. R. Taylor, 'New Zealand «pd its Inhabitants,' 1855, p. 152.
44 Mantcgazza, 1 Viaggi e Studi,' p. 542.

Chap. XIX.]

BEAUTY.

327

and often in a different manner ; sometimes, though rarely,
the women are hardly at all ornamented. As the women
are made by savages to perform the greatest share of the
work, and as they are not allowed to eat the best kinds
of food, so it accords with the characteristic selfishness of
man that they should not be allowed to obtain, or to use,
the finest ornaments. Lastly, it is a remarkable fact, as
proved by the foregoing quotations, that the same fash-
ions in modifying the shape of the head, in ornamenting
the hair, in painting, tattooing, perforating the nose, lips, or
ears, in removing or filing the teeth, etc., now prevail and
have long prevailed in the most distant quarters of the
world. It is extremely improbable that these practices
which are followed by so many distinct nations are due to
tradition from any common source. They rather indicate
the close similarity of the mind of man, to whatever race
he may belong, in the same manner as the almost univer-
sal habits of dancing, masquerading, and making rude
pictures.

Having made these preliminary remarks on the admi-
ration felt by savages for various ornaments, and for de-
formities 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. As I have heard it main-
tained that savages are quite indifferent about the beauty
of their women, valuing them solely as slaves, it may be
well to observe that this conclusion does not at all agree
with the care which the women take :-- ornamenting then -
selves, or with tlieir vanity. Bu; ' gives an amusing
account of a Bushwoman, who used so much grease, red
ochre, and shining-powder, tk as would have ruined any
but a very rich husband." She displayed also "much
vanity ami too evident a consciousness of her superiority."
41 "Travels in South Africa,' 1894, vol. i. p, 11 I.

328

SEXUAL SELECTION: MAN.

[Part IT.

Mr. Winwood Reade informs mc that the negroes of the
West Coast often discuss the beauty of their women
Some competent observers have attributed the fearful h
common practice of infanticide partly to the desire felt t J
the women to retain their good looks.48 In several regioi I
the women wear charms and love-philters to gain the | ft -
tions of the men ; and Mr. Brown enumerates four plfcntfl
used for this purpose by the women of North w
America.49

Hearne,60 who lived many years with the American
Indians, and who was an excellent observer, says, in spc:ik
ing of the women, " Ask a northern Indian what is beau ,
and he will answer, a broad flat face, small eyes,
cheek-bones, three or four broad black lines across
. cheek, a low forehead, a large broad chin, a clumsy hool:
nose, a tawny hide, and breasts hanging down to the belt."
Pallas, who visited the northern parts of the Chinese em-
pire, says, "Those women are preferred who have the
Mandschu form; that is to say, abroad face, high ch < k-
bones, very broad noses, and enormous ears ; " " and
Vogt remarks that the obliquity of the eye, whi I
proper to the Chinese and Japanese, is exaggcrat 1 . .
their pictures for the purpose, as " it seems, of exhibiting itFi
beauty, as contrasted with the eye of the red-haired bar-
barians." It is well known, as Hue repeatedly rerr il rfa
that the Chinese of the interior think Europeans hi<J< «.i
with their white skins and prominent noses. The nose il*

48 See, for reference*, 1 Gerland iiber das Aussterben der Naturvolke.*,'
1868, s. 51, 53, 55 ; alio Stmm, ' Yoyagae,' etc., torn, il p. 116.

49 On the vegetable prodtattas uaed by the Northwestern America i
Indians, ' Pharmaceutical Journal,' toL x.

60 'A Journey from Prince of Wales Fort,' 8vo edit. 1796, p. 89.

61 Quoted by Prichard, 'Phya. Hiat. of Mankind,' 3d edit, v.»l. i\ .
18-14, p. 519; Vogt, 4 Lectures on M n,' Eng. translat. p. 120. On the
opinion of the Chinese on the Cingalese, E. Tennent, 'Ceylon,' • I I
1859, p. 107.

Chap. XIX.]

BEAUTY.

329

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 Mogul
races, were surprised at the prominent noses of the Cinga-
lese ; and Thsang described them as having 1 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 diver-
gent nostrils, a wide mouth, rather thick lips, a remarkably
large face, with very high and broad cheek-bones. It is,
therefore, not wonderful that " beauty, according to our
notion, is a stranger to them. Yet they consider their own
females to be much more beautiful than those of Eu-
rope." 62

It is well known that with many Hottentot women the
posterior part of the body projects in a wonderful manner ;
they are steatopygous ; and Sir Andrew Smith is certain
that this peculiarity is greatly admired by the men." He
once saw a woman who was considered a beauty, and she
was so immensely developed behind, that when seated on
level ground she could not rise, and had to push herself
along until she came to a slope. Some of the women in
various negro tribes arc similarly characterized ; and, ac-
cording to Burton, the Somal men " are said to choose
their wives by ranging them in a line, and by picking her

63 Pricliard, as taken from Crawford and Finlayson, 4 Phys. Hist, of
Mankind,' vol. iv. pp. BJM, 635.

53 "Idem illustriHsimus viator dixit mihi pru'cinetorinm vcl tabula
ficmimc, quod nobis tctcrrimuin est, quondam porniagno astiinaii ab
hominibus in liac gente. Nunc res mutata est, ct eenset talem confor-
mational! minimu optandam est."

330

SEXUAL SELECTION: MAN.

[Pabt IL

out who projects farthest a. tergo. Nothing can be more
hateful to a negro than the opposite form." 64

With respect to color, 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 unnat-
ural conformations." He in return praised the glossy jet
of their skins and the lovely depression of their noses ;
this they said was "honey-mouth," nevertheless they ga\ 6
him food. The African Moors, also, "knitted their brows
and seemed to shudder " at the whiteness of his skin. On
the eastern coast, the negr* 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 white-
ness may be partly attributed, according to this same
traveller, to the belief held by most negroes that demons
and spirits are white.

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 color, and, indeed, this color is considered hand-
some throughout the whole country ; " so that here we
have a different standard of taste. With the Kaffres, who
differ much from negroes, " the skin, except among the
tribes near Delagoa Bay, is not usually black, the prevail-
ing color being a mixture of black and red, the most com-
mon shade being chocolate. Dark complexions, as being
most common, are naturally held in the highest esteem.
To be told that he is light-colored, or like a white man,
would be deemed a very poor compliment by a Kaffre. I
have heard of one unfortunate man who was so very fair
that no girl would marry him." One of the titles of the *

M 1 Thu Anthropological Review,' Nov. 1864, p. 237. For additional
reference?, bcc Waitz, 'Introduct. to Anthropology,' Eng. transht. 18o:5,
vol. i. p. 105.

Chap. XIX.]

BEAUTY.

331

Zulu king is, " You who are black." 66 Mr. Galton, in
speaking to me about the natives of Southern Africa, re-
marked that their ideas of beauty seem very different from
ours ; for in one tribe two slim, slight, and pretty girls were
not admired by the natives.

Turning to other quarters of the world : in Java, a
yellow, not a white girl, is considered, according to Ma-
dame 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 color like that
of potato-flowers.,, We have seen that the Chinese dislike
our white skin, and that the North Americans admire " a
tawny hide." In South America, the Yura-caras, who in-
habit the wooded, damp slopes of the eastern Cordillera,
are remarkably pale-colored, as their name in their own
language expresses ; nevertheless, they consider European
women as very inferior to their own.68

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 South America
likewise have very long hair ; and this, as Mr. D. Forbes
informs me, is so much valued for the sake of beauty, that
cutting it off was the severest punishment which he could
inflict on them. In both halves of the continent the na-

55 'Mungo Park's Travels in Africa/ 4to, 1810, pp. 58, 131. Burton's
statement is quoted by Schaaffhausen, ' Archiv fttr Anthropolog.' 1888,
a. 163. On the Ranyai, Livingstone, 'Travels,' p. 84 On the Kafirs,
the Rev. J. Shooter, 4 The Kafirs of Natal and the Zulu Country,' 1S57,

rp.i.

"For the Javanese and Cochin- Chinese, see Wait/., « Introduet. to
Anthropology,' Eng. translut. vol. i. p. ;t<>:,. On the Yuia-eanis, A.
d'Orligny, as quoted in Rritehanl, * Rhys. Hist, of Mankind,' vol. v. M
edit. p. 470.

332

SEXUAL SELECTION: MAN.

[Part H,

tives sometimes increase the apparent length of their hair
by weaving into it fibrous substances. Although the bail
on the head is thus cherished, that on the face is consider* <l
by the North American Indians " as very vulgar," and
every hair is carefully eradicated. This practice prevails
throughout the American Continent from Vancouver's Isl-
and 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 thre ttened
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 a hairy man. This fashion is
carried to such an extreme that the Indians of Paraguay
eradicate their eyebrows and eyelashes, saying that they
do not wish to be like horses."

It is remarkable that throughout the world th-- races
which are almost completely destitute of a beard dislike
hairs on the face and body, and take pains to eradicate
them. The Calmucks are beardless, and they are well
known, like the Americans, to pluck out all straggling
hairs; and so it is with the Polynesians, some of the
Malays, and the Siamese. Mr. Veitch states that the
Japanese ladies " all objected to our whiskers, considering
them very ugly, and told us to cut them off, and be like
Japanese men." The New-Zealanders are beardless ; they
carefully pluck out the hairs on the face, and have a
saying that " there is no woman for a hairy man. " 68

67 North American Indians,' by G. Catlin, 3d. edit. 1842, vol i. p. 49;
vol. ii. p. 227. On the natives of Vancouver Island, sec Sproat. 4 Scrne*
and Studies of Savage Life,' 1868, p. 25. On the Indians of Paraguay,
Azara, ' Voyages,' torn. iL p. 105.

68 On the Siamese, Pritchard, ibid. vol. iv. p. 533. On the Japane>e,
Veitch in 1 Gardeners' Chronicle,' 1860, p. 1104. On the New-Zea1 1 \derp,
Mantegazza, 1 Viaggi e Studi,' 1867, p. 526. For the other nation- men

« HA.P. XIX.]

BEAUTY.

333

On the other hand, bearded races admire and greatly
value their beards ; among the Anglo-Saxons every part
cf the body, according to their laws, had a recognized
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, evidently thought that beards were a
great ornament. With the Fijians in the Pacific the
beard is " profuse and bushy, and is his greatest pride ; "
while the inhabitants of the adjacent archipelagoes of
Tonga and Samoa are "beardless, and abhor a rough
chin." In one island alone of the Ellice group " the men
are heavily bearded, and not a little proud thereof." 60

We thus see how widely the different races of man
differ in their taste for the beautiful. In every nation
sufficiently advanced to have made effigies of their gods
or of their deified rulers, the sculptors no doubt have en-
deavored to express their highest ideal of beauty and
grandeur." Under this point of view it is well to com-
pare in our mind the Jupiter or Apollo of the Greeks with
the Egyptian or Assyrian statues; and these with the
hideous bass-reliefs on the ruined buildings of Central
America.

I have met with very few statements opposed to the
above conclusion. Mr. Winwood Reade, however, who
hae had ample opportunities for observation, not only
with the negroes of the West Coast of Africa, but with

tioned, see references in Lawrence, 'Lectures on Fhysiology,' etc. 1822,
p. 272.

«• Lubbock, •Origin of Civilization,' 1870, p. 321.

M Dr. Barnard Davis quotes Mr. Pritchard and others for those facts
in regard to the Polynesians, in 1 Anthropological Review,' April, 1870,
pp. 185, 191.

•! Ch. Comtc has remarks to this effect in his ' Traito do Legislation,'
8d. edit. 1837, p. 130.

334

SEXUAL SELECTION: MAN.

[Part II.

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. He has repeatedly found that
lie agreed with negroes in their estimation of the beauty
of the native girls; and that their appreciation of the
beauty of European women corresponded with ours.
They admire long hair, and use artificial means to make
it appear abundant; they admire also a beard, though
themselves very scantily provided. Mr. Reado feels
doubtful what kind of nose is most appreciated: a girl
has been heard to say, " I do not want to marry him, he
has got no nose ; " and this shows that a very flat nose is
not an object of admiration. We should, however, bear
in mind that the depressed and very broad noses and pro-
jecting jaws of the negroes of the West Coast are excep-
tional types with the inhabitants of Africa. Notwith-
standing the foregoing statements, Mr. Reade 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 truth of the principle, long ago insisted on by
Humboldt," that man admires and often tries to exa^er-
ate whatever characters Nature may have given him, is
shown in many ways. The practice of beardless races

M The Fuegians, a3 I have been informed by a missionary who long
resided with them, consider European women as extremely beautiful ;
but from what we have seen of the judgment of the other aborigines of
America, I cannot but think that this must be a mistake, unless indeed
the statement refers to the few Fuegians who have lived for some time
with Europeans, and who must consider us as superior beings. I should
add that a most experienced observer, Captain Burton, believes that a
woman whom we consider beautiful is admired throughout the world,
'Anthropological Review,' March, 18C4, p. 245.

63 'Personal Narrative,' Eng. translat. vol iv. p. 518, and elsewhere.
Mantegazza, in his ' Viaggi e Studi,' 1867, strongly insists on this samo
principle.

Chap. XIX.] BEAUTY. ■ 335

extirpating every trace of a beard, and generally all the
hairs on the body, offers one illustration. The skull has
been greatly modified during ancient and modern times
by many nations; and there can be little doubt that thi3
has been practised, especially in North and South Amer-
ica, in order to exaggerate some natural and admired pe-
culiarity. Many American Indians are known to admire
a head flattened to such an extreme degree as to appear
to us like that of an idiot. The natives on the north-
v< stern coast compress the head into a pointed cone;
and it is their constant practice to gather the hair into a
kr.ot on the top of the head, for the sake, as Dr. Wilson
remarks, " of increasing the apparent elevation of the
favorite conoid form." The inhabitants of Arakhan " ad-
mire 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 ex-
aggerating a natural conformation." With the Tahitians,
to be called long-nose is considered as an insult, and they
compress the noses and foreheads of their children for the
sake of beauty. So it is witli the Malays of Sumatra, the
Hottentots, certain Negroes, and the natives of Brazil."

64 On tho skulls of the American tribes, see Nott and Gliddon, 1 Types
of Mankind,' 1854, p. 440 ; Pritchard, 'Phys. Hist, of Mankind,' vol. i. 3d
edit. p. 321; on the natives of Arakhan, ibid. vol. iv. p. 537. Wilson,
' Pliysiml Ethnology,' Smithsonian Institution, 1863, p. 288; on tho
Fijians, p. 290. Sir J. Lubbock ('Prehistoric Times,' 2d edit. 18(»'.», p.
606) gives an excellent rhumo on this subject.

•* On tho Huns, Godron, 'Do l'Espftde,' torn. ii. is.v.>, p. 300. On tho
Tahitianfl, Wait/., ' Anthropolog.' Eng. translat. vol. i. p. 305. Marsdni,

336

SEXUAL SELECTION: MAN.

[Tart II.

The Chinese have by nature unusually small feet ; "
and it is well known that the women of the upper classes
distort their feet to make them still smaller. Lastly, Hum-
boldt thinks that the American Indians prefer coloring
their bodies with red paint in order to exaggerate their
natural tint; and until recently European women a<Mnl
to their naturally bright colors by rouge and white OQt-
metics; but I doubt whether many barbarous nations
have 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 emula-
tion. But the fashions of savages are far more permanent
than ours ; and whenever their bodies are artificially mod-
ified this is necessarily the case. The Arab women of
the Upper Nile occupy about three days in dressing their
hair; they never imitate other tribes, " but simply vie
with each other in the superlativeness of their own style."
Dr. Wilson, in speaking of the compressed skulls of vari-
ous American races, adds, " Such usages are among the
least cradicable, and long survive the shock of revolu-
tions that change dynasties and efface more important
national peculiarities." ,T The 6ame principle comes large-
ly into play in the art of selection; and we can thus un-
derstand, as I have elsewhere explained," the wonderful
development of all the races of animals and plants which
are kept merely for ornament. Fanciers always wish each
character to be somewhat increased; they do not admire

quoted by Trite-hard, 4 Pbys. Hist, of Mankind,' 3d edit. voL v. p. 67.
Lawrence, 4 Lectures on Physiology,' p. 337.

M This fact was ascertained in the * Rcise dcr Xovara : Anthropolog.
TheiV Dr. Weisbach, 1867, 8. 265.

151 'Smithsonian Institution,' 1863, p. 289. On the fashions of Arab
women, Sir S. Baker, 'The Nile Tributaries,' 1867, p. 121.

M 4 The Variation of Animala and Tlants under Domestication,' vol. L
p. 214 ; voL iL p. 240.

Chap. XIX.]

BEAUTY.

337

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 behold, but
they ardently desire to see each characteristic feature a
little more developed.

No doubt the perceptive powers of man and the lower
animals are so constituted that brilliant colors and certain
forms, as well as harmonious and rhythmical sounds, give
pleasure and are called beautiful ; but why this should be
so, we know no more than why certain bodily sensations
are agreeable and others disagreeable. It is certainly not
true that there is in the mind of man any universal stand-
ard of beauty with respect to the human body. It is, how-
ever, possible that certain tastes may in the course of time
become inherited, though I know of no evidence in favor
of this belief; and if so, each race would possess its own
innftte ideal standard of beauty. It has been argued 09
that ugliness consists in an approach to the structure of
the lower animals, and this no doubt is true with the more
civilized nations, in which intellect is highly appreciated ;
but a nose twice as prominent, or eyes twice as large as
usual would not be an approach in structure to any of the
lower anim tls, and yet would be utterly hideous. The
men of each race prefer what they arc accustomed to be-
hold ; they cannot endure any great change; but they like
variety, and admire each characteristic point carried to a
moderate extreme.70 Men accustomed to a nearly oval
face, to straight and regular features, and to bright colors,
admire, as we Europeans know, these points when strongly
developed On the other hand, nun accustomed to a
broad ffcoe, With high cheek-bones, a depressed nose, and

• MuutfTkanicn, ' Archiv filr Anthropologic,1 ISM, «. lr.l.

10 Mr. Bftl&fcai collected (4 Mental and Moral Science,' Is.;*, pp.
314) about u <loj-.cn tnorr or Ii-m dill',.,, ,it theories of the i.le i ol bi nut} ;
but none arc quite the ;i with tli.it heir -ism.

..'If

338

SEXUAL SELECTION: MAN.

[Part II.

a black skin, admire these points strongly developed. No
doubt characters of all kinds may easily be too much de-
veloped for beauty. Hence a perfect beauty, which im-
plfes many characters modified in a particular manner, will
in every race be a prodigy. As the great anatomist Bi-
chat 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 do
Medici, we should for a time be charmed ; but we should
soon wish for variety; and as soon as we had obtained
variety, we should wish to see certain characters in our
women a little exaggerated beyond the then existing con>
mon standard.

Chap.XX.1 SEXUAL SELECTION: MAN.

339

CHAPTER XX.

Secondary Sexual Characters of Man — continued.

On the Effects of the Continued Selection of "Women according to a
Different Standard of Beauty in each Race. — On the Causes which
interfere with Sexual Selection in Civilized and Savage Nations. —
Conditions favorable to Sexual Selection during Primeval Times. — On
the Manner of Action of Sexual Selection w ith Mankind.— On the
Women in Savage Tribes having some Pow er to choose their Hus-
banus. — Absence of Hair on the Body, and Development of the Beard.
— Color of the Skin. — Summary.

We have seen in the last chapter that with all barbar-
ous races ornaments, dress, and external appearance, are
highh valued ; and that the men judge of the beauty of
their women by widely-different standards. We must
next inquire whether this preference and the consequent
selection during many generations of those women, which
appear to the men of each race the most attrac tive, lias
altered the character either of the females alone or of both
sexes. With mammals the general rule appears to be tliat
ohftrieteri €>f all kinds are inherited equally by the males
and females; we might therefore expect thai with man-
kind any characters gained through sexual Beleotion by
the females would commonly be transferred to the off
spring of both sexes, [f any change has thus been ef-
fected it is almost certain that the different races will ha\e
bec*n differently modified, as each has its <»w □ standard of
beauty.

"With mankind, especially with savages, manj causes

340 SEXUAL SELECTION: MAN. [Part II.

interfere with the action of sexual selection as far as the
bodily frame is concerned. Civilized men are largely at-
tracted by the mental charms of women, by their wealth,
and especially by their social position ; for men rarely
marry into a much lower rank of life. The men who suc-
ceed in obtaining the more beautiful women, will not have
a better chance of leaving a lone: line of descendants than
other men with plainer wives, with the exception of the
few who bequeath their fortunes according to primogeni-
ture. With respect to the opposite form of selection,
namely, of the more attractive men by the women, al-
though in civilized 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 largely depends on their intellectual powers and energy,
or on the fruits of these same powers in their forefathers.

There is, however, reason to believe that sexual se-
lection has effected something in certain civilized and
semi-civilized nations. Many persons are convinced, as it
appears to me with justice, that the members of .our aris-
tocracy, including under this term all wealthy families in
which primogeniture has long prevailed, from having
chosen during many generations from all classes the more
beautiful women as their wives, have become handsomer,
according to the European standard of beauty, than the
middle classes ; yet the middle classes are placed under
equally favorable conditions of life for tho perfect devel-
opment of tho body. Cook remarks that the superiority
in personal appearance "which is observable in the erees
or nobles in all the other islands (of tho Pacific) is found
in the Sandwich islands but this may be chiefly due to
their better food and manner of life.

The old traveller Chardin, in describing the Persians,
says their " blood is now highly refined by frequent inter-

XX.] SEXUAL SELECTION: MAN.

341

mixtures with the Georgians and Circassians, two nations
which surpass all the world in personal beauty. There is
hardly a man of rank in Persia wrho is not born of a Geor-
gian or Circassian mother." He adds that they inherit
their beauty, " not from their ancestors, for without the
above mixture, the men of rank in Persia, who are de-
scendants of the Tartars, would be extremely ugly." 1
Here is a more curious case : the priestesses who attended
the temple of Yenus Erycina at San-Giuliano in Sicily,
were selected for their beauty out of the whole of Greece ;
they were not vestal virgins, and Quatrefages,2 who makes
this statement, says that the women of San-Giuliano are
famous at the present day as the most beautiful in the
island, and are sought by artists as models. But it is ob-
vious that the evidence in 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 remarkable for their uniformly
fine appearance." A friend of his asked one of these men,
" How is it that every one whom I meet is so fine-looking,
not only your men, but your women ? " The Jollof an-
swered, "It is very easily explained: it has always been
our custom to pick out our worse-looking slaves and to
sell them." It need hardly be added that with all sav-
ages female slaves serve as concubines. That this negro
should have attributed, whether riglitly or wrongly, the
fine appearance of his tribe to the long-continired elimina-
tion of the ugly women, is not so surprising as it may at
first appear; tor I have elsewhere shown that negroes

1 These quotations arc taken from LaWT0D06 (' LectUMI OB Phyttol
ogy. etc. IK'JL', p. :t'.t:;;, who attributes the beauty of the upper classes in

England to the men having long lelected the more beautiful woman.

» "Anthropologic1," ' Revuo den Coins Sciciitiliqucs,' Oct. 1S(*.H, p.

342

SEXUAL SELECTION: li.

fully appreciate the importance of selection in the
ing of their domeitic animals,1 and I could giw I
Reade additional evidence on this head.

On the Causes which prevent or check t/t Action of
Sexual Selection with Savages. — The chief causes are,
firstly, so-called communal marriages or promiscuous in-
tercourse ; secondly, infanticide, especially of female in
fants; thirdly, early betrothals ; and lastly, the low esti-
mation in which women are held, as mere slaves. Tl
four points must he considered in some detail.

It is obvious that as long as the pairing o man, or of
any other animal, is left to chance, with no ch >ice exerted
by either sex, there can be no sexual select on; and
effect will be produced on the olfsjn-ing by certain in
viduals haying had an advantage over others in their
courtship. Now it is asserted that there exist it th pres-
ent day tribes which practise what Sir J. Lubbock by
courtesy calls communal marriages ; that is, all the nu n
and women in the tribe are husbands and w v< i t-» each
other. The licentiousness of many savages is no doubt
astonishingly great, but it seems to me that, more evi-
dence is requisite before we fully admit that tl eir existing
intercourse is absolutely promiscuous. Nevertheless all
those who have most closely studied the si bjeet,4 and

* 'The Variation of Animals and Plants under Domestication,' vol i.
p. 207

* Sir J. Lubbock, * The Origin of Civilization,' 1870, chap. iii. cape*
cially pp. C0-G7. Mr. McLennan, in his extremely valuable work on
4 Primitive Marriage,' 1865, p. 1»*>.'5, speaks of tlic union of tl:-- < \a "in
the earliest times as loose, transitory, and in some degree promise uous.'*
Mr. McLennan and Sir J. Lubbock have collected much evidence on tlx
extreme licentiousness of savages at the present time. 3Ir. L. II. Mor-
gan, in his interesting memoir on the classificatory system of relationship
(* Proc. American Acad, of Sciences,' vol. vii. Feb. 1868, p. 475 J OOm
eludes that polygamy and all forms of marriage during primeval times

INTERFERING CAUSES.

343

judgment is worth much more than mine, believe
^ommunal marriage was the original and universal
.urm throughout the world, including the intermarriage
of brothers and sisters. The indirect evidence in favor
of this belief is extremely 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 alone, and not with either parent. But the sub-
ject 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 communal marriages, or where
the marriage-tie is very loose, that the relationship of the
child to its father cannot be know*. But it seems almost
^edible that the relationship of the child to its mother
aid ever have been completely ignored, especially as
the women in most savage tribes nurse their infants for a
long time. Accordingly in many cases the lines of de-
scent are traced through the mother alone, to the exclusion
of the father. But in many other cases the terms em-
ployed express a connection with the tribe alone, to the
exclusion even of the mother. It seems possible that the
connection between the related members of the same bar-
barous tribe, exposed to all sorts of danger, might be so
much more important, owing to the need of mutual pro-
tection 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 of the case is by no means sufficient.

The terms of relationship used in different parts of the
world may be divided, according to tho author just
quoted, into two great classes, the classiiicat ory and de-
scriptive— the Latter being employed by us. It is tl o

were essentially unknown. It appears, also, from Sir J. I,ul>1>oek'a work,
that Btehofen likewise belierei that oommaiud tnterooum originally
prevailed.

344 SEXUAL SELECTION* : MAN. [I

classificatory system which so strongly leads to t1 b
that communal and other extremely loose form!
riagc were originally universal. But, as far as 1
there is no necessity on this ground for believing in
luU'ly promiscuous intercourse. Men and women, lib.
many of the lower animals, might formerly have entered
into strict though temporary unions for each birth, an<l in
this case nearly as much confusion* would have antea in
the terms of relationship as in the case of promiscuous in-
tercourse. As far as sexual selection is concerned, all that
is required is that choice should be exerted before the m
cuts unite, and it signifies little whether the unions lust
for life or only for a season.

Besides the evidence derived from the terms* of w la
tionship, other lines of reasoning indicate the former wide
prevalence of communal marriage. Sir J. .Lubbock in-
geniously accounts 6 for the strange and widely-
habit of exogamy — that is, the men of one tribe always
taking wives from a distinct tribe — by communism hav-
ing been the original form of marriage; so that a man
never obtained a wife for himself unless he captured iht
from a neighboring and hostile tribe, and then she would
naturally have become his sole and valuable property.
Thus the practice of capturing wives might have arisen j
and from the honor so gained might ultimately have
come the universal habit. We can also, according to Sir
J. Lubbock,* thus understand "the necessity of cxpiai oD
for marriage as an infringement of tribal rites, sii a . ac-
cording 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 most curious body of facts show-
ing that in old times high honor was bestowed on women
who wTere utterly licentious ; and this, as he explains, is

8 Address to British Association ' On the Social ami II '
tion of the Lower Races of Man,' 1870, p. 20.

XX.]

INTERFERING CAUSES.

345

intelligible, if we admit that promiscuous intercourse was
the p1 original and therefore long-revered custom of the

although the manner of development of'the marriage-
tie is an obscure subject, as we may infer from the diver-
gent opinions on several points between the three authors
who* have studied it most closely, namely, Mr. Morgan,
Mr. McLennan, and Sir J. Lubbock, yet from the forego-
ing and several other lines of evidence it seems certain
that the habit of marriage has been gradually developed,
and that almost promiscuous intercourse was once ex-
tremely common throughout the world. Nevertheless,
from the analogy of the lower animals, more particularly
of those which come nearest to man in the series, I cannot
believe that this habit prevailed at an extremely remote
period, when man had hardly attained to his present rank
in the zoological scale. Man, as I have attempted to
show, 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, as
seems to be the case with the Orang. Several kinds, as
some of the Indian and American monkeys, are strictly
monogamous, and associate all the year round with their
wives. Others arc polygamous, as the Gorilla and sev-
eral American species, and each family lives separate;
Even when this occurs, the families inhabiting (lie same
district are probably to a certain extent soeial : the Chim-
panzee, for instance, is occasionally met with in large
bands. Again, other species are polygamous, but several-
males, each with their own females, live associated in a

c< Origin of Civilization,' ls'<"<>, ]>. ST.. In iln> M\cral works ahove

. quoted there will bo round coploui evidence on relationship through tho
MmIm alone, or with the tribe alone.

346

SEXUAL SELECTION: MAX.

body, as with several species of Baboons.7 We in.,
deed conclude from what we know of the jealousy «»1
male quadrupeds, armed, as many of them are, with spe-
cial weapons "for battling with their rivals, that pr<
cuous intercourse in a state of nature is extremely improb-
able. The pairing may not last for life, but only for I m -h
birth ; yet if the males which arc the strongest and best
able to defend or otherwise assist their females and \onng
offspring, were to select the more attractive females, tins
would suffice for the work of sexual selection.

Therefore, if we look far enough back in the stn am
time, it is extremely improbable that primeval ma
women lived promiscuously together. Judging
60cial habits of man as lie imw c\'i-ts and fr.nn in
ages being polygamists, the most probable view is that
primeval man aboriginally lived in small commum
each with as many wives as he could support and in.
whom he would have jealously guarded against all other
men. Or he may have lived with several wives by him-
• self, like the Gorilla ; for all the natives " agree that '.ut
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, estab-
lishes himself as the head of the community."* Tit
younger males, being thus expelled and wandering ab nit,
would, when at last successful in finding a partner, pre-
vent too close interbreeding within the limits of the same
family.

T Brchm (' Illust. Thicrleben,' B. L p. 77) says Cynoerphalu* Kama-
dryat lives in great troops containing twice as many adult f males as
adult males. See Rengger on American polygamous species, and Owen
(; A n.it. of Vertebrates,' vol. iii. p. 746) on American monogamous spe- .
cies. Other references might be added.

'Dr. Savage, in ' Boston Journal of Nat Hist.' vol„iV, 1840-'47, p.
423.

]

INTERFERING CAUSES.

347

* Although savages are now extremely licentious, and
alt7 ough communal marriages may formerly have largely
prevailed, yet many tribes practise some form of mar-
riage, but of a far more lax nature than with civilized
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, accord-
ing to Sir J. Lubbock,9 " that death alone can separate hus-
md and wife." An intelligent Kandyan chief, of course
:>lygamist, "was perfectly scandalized at the utter
■irism of living with only one wife, and never parting
i.. A separated by death." It was, he said, "just like the
Wanderoo monkeys." Whether savages who now enter
into some form of marriage, either polygamous or monog-
amous, have retained this habit from primeval times, or
whether they have returned to some form of marriage,
after passing through a stage of promiscuous intercourse,
I will not pretend to conjecture.

Infanticide. — This practice is now very common
throughout the world, and there is reason to believe that
it prevailed much more extensively during former times.10
Barbarians find it difficult to support themselves and their
children, and it is a simple plan to kill their infants. In
South America some tribes, as Azara states, formerly de-
stroyed so many infants of both sexes, thai tiny were on
the point of extinction. In the Polynesian Islands wom-
en have been known to kill from lour or five to even ten
Of their children ; and Kllis could not lind a single woman
who had not killed at least one. Wherever infanticide

• • * Prehistoric Times,' lN<5t>, p. Ul.
*Mr. MoLcnnnn, 4 Primitive! Man I si;:, S» .• |>.-. iulh on <\-
ogamj ami Infanticide, yy. l:in, |:;s, If,;,.

348

SEXUAL SELECTION: MAX.

[Pajit a

prevails the struggle for existence will be in so fur less
severe, and aU the members of the tribe will have an al-
most 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 most 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 esti-
mation set on them and their happier fate, when few in
number, 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 Maccul-
loch found not a single female child.11

When, owing to female infanticide, the women of a
tribe are few in number, the habit of capturing wives
from neighboring tribes wrould naturally arise. Sir J.
Lubbock, however, as we have seen, attributes the prac-
tice, 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 com-
munities being very small, in which case, marriageable
women would often be deficient. That the habit of cap-
ture was most extensively practised during former times,
even by the ancestors of civilized nations, is clearly shown
by the preservation of many curious customs and cere-
monies, of which Mr. McLennan has given a most inter-

" Dr. Garland ('Ucbcr da8 Ausstcrben dcr Natnrvolker,' 1868) has
collected much information on infanticide, see c.-pceially b. 27, 51, 64.
Azara ('Voyages,' etc., torn. ii. pp. 94, 116) enters in detail on the mo-
tives. See also McLennan (ibid. p. 139) for cases in India.

Chap. XX.]

INTERFERING CAUSES.

349

estmg account. In our own marriages the " best man "
seems originally to have been the chief abettor of the
bridegroom in the act of capture. Now, as long as men
habitually procured their wives through violence and
craft, it is not probable that they would have selected the
more attractive women ; they would have been too glad
to have seized on any woman. But as soon as the prac-
tice of procuring wives from a distinct tribe was effected
through barter, as now occurs in many places, the more
attractive women would generally have been purchased.
The incessant crossing, however, between tribe and tribe,
which necessarily follows from any form of this habit
would have tended to keep all the people inhabiting the
same country nearly uniform in character ; and this would
have greatly interfered with the power of sexual selection
in differentiating the tribes.

The scarcity of women, consequent on female infanti-
cide, leads also to another practice, namely, polyandry,
which is still common in several parts of the world, and
whioh formerly, as Mr. McLennan believes, prevailed al-
most universally; but this latter conclusion is doubted by
M r. Morgan and Sir J. Lubbock.13 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 attrac-
tive women. J>ut, under these circumstances, the women
no doubt will have the power of choice, and will prefer
th( more attractive men. Azara, for instance, describes
how carefully a Guana woman bargains for all sorts of
privUeges before accepting some one or more husbands;
and the men in consequence tako unusual care of their

'• ' Primitive Mania"..,' ,,. 'jiis; Sir .1. LiiMmmK, « < >i i-in of Civ ili/.u-
Jon/ p. lo<>. Sr.- iil.-iii Mi. Morgan, loc. uit., on fonnoi prevalence of
polyandry.

350

SEXUAL SELECTION': MAN.

[Paiit II.

personal appearance.1* The very ugly men would perhaps
altogether fail in getting a wife, or get one later in life,
but the handsomer men, although the most successful in
obtaining wives, would not, as far as we can see, leave
more offspring to inherit their beauty than the less hand-
some husbands of the same women.

Early Betrotjials and Slavery of Women. — With many
savages it is the custom to betroth the females while mere
infants; and this would effectually prevent preference be-
ing exerted, on either side, according to personal appear-
ance. But it would not prevent the more attractive
women from being afterward stolen or taken by force
from their husbands by the more powerful men; and this
often happens in Australia, America, and other parts of
the world. The same consequences with reference to
sexual selection would to a certain extent follow when
women are valued almost exclusively as slaves or beasts
of burden, as is the ease with most savages. The m< n,
however, at all times would prefer the handsomest slaves
according to their standard of beauty.

We thus see tfoat several customs prevail with savar
which would greatly interfere with, or completely e
the action of sexual selection. On the other hand, m.
conditions of life to which savages are exposed, and some
of their habits, are favorable to natural selection; and
tlii< always comes into play together witli sexual selec-
tion. Savages are known to sutler severely from recur-
rent famines ; they do not increase their food by artificial
means; they rarely refrain from marriage,*' and generally

11 1 Voyages,' etc., torn. ii. pp. 92-95.

14 Burchell Bays (• Travels in South Africa,' voL ii. 1824, p. 58), that
among the wiM nations of Southern Africa, neither men nor women over
pass their livei in a etate of celibacy. Azara ('Voyages dano PAnx rique

Chap. XX.]

MANNER OF ACTION.

351

marry young. Consequently they must be subjected to
occasional hard struggles for existence, and the favored
individuals will alone survive.

Turning to primeval times when men had only doubt-
fully attained the rank of manhood, they would probably
have lived, as already stated, either as polygamists or
temporarily as monogamists. Their intercourse, judging
from analogy, would not then have been promiscuous.
They would, no doubt, have defended their females to the
best of their power from enemies of all kinds, and would
probably have hunted for their subsistence, as well as for
that of their offspring. Tire most powerful and able
males would have succeeded best in the struggle for life
and in obtaining attractive females. At this early period
the progenitors of man, from having only feeble powers
of reason, would not have looked forward to distant con-
tingencies. They would have been governed more by
their instincts and even less by their reason than are
navag.es at the present day. They would not at that
period have partially lost one of the strongest of all in-
stincts, common to all the lower animals, namely, the love
of their young offspring; and consequently they would
have practised infanticide. There would have been
;*{cartificial scarcity of women, and polyandry would not
ja've been followed ; there would have been no early be-
trothals; women would not have; been valued as mere
slaves; both sexes, if the females as well as the males
were permitted to exert, any choice, would have chosen
their partners, not for mental charms, or properly, or
social position, but almost, solely from external appear-
ance. All tlx- adults would have married or paired, and
all tlye offspring, as far as that \\:e^ possible, would have
been reared; so that the struggle for existence would

Merid.' lom. ii. Isn't, p. '.* 1 ) maKi-H .l\ id.- .inn n iii. iik iii nyuiA

• to the wiM IndiatiH ol South Auicricn.

352

SEXUAL SELECTION: MAN.

[Part ft

have been periodically severe to an extreme degree.
Thus during these primordial times allthe conditions for
sexual selection would have been much more favorable
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 much more powerful at a very
remote period than at the present day.

On the Manner of Action of Sexual Selection with
Mankind. — With primeval men under the favorable con-
ditions just stated, and with those savages who at the
present time enter into any marriage-tie (but subject to
greater or less interference according as the habits of
female infanticide, early betrothals, etc., are more or less
practised), sexual selection will probably have acted in
the following manner : The strongest and most vigorous
men — those who could best defend and hunt for their
families, and during later times the chiefs or head-men —
those who were provided with the bdst weapons and who
possessed the most property, such as a larger number of
dogs or other animals, would have succeeded in rearing a
greater average number of offspring, than would the
weaker, poorer, and lower members of the same tribes.
There can, also, be no doubt that such men would gener-
ally have been able to select the more attractive women.
At present the chiefs of nearly every tribe throughout
the world succeed in obtaining more than one wife. Un-
til recently, as I hear from Mr. Mantell, almost every girl
in New Zealand, who was pretty, or promised to be
pretty, was tnpu t<> sonic chief. "With tlie Kaffrcs, as Mr.
C. Hamilton states,16 " the chiefs generally have the pick

15 'Anthropological Review,' Jan. 1870, p. xvl

Chap. XX.]

MANNER OF ACTION.

353

of the women for many miles round, and are most perse-
vering 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 charac-
teristic point in his domestic animals, dress, ornaments,
and personal appearance, when carried a little beyond the
common standard. If, then, the several foregoing proposi-
tions be admitted, and I cannot see that they are doubtful,
it would be an inexplicable circumstance, if the selection
of the more attractive women by the more powerful men
of each tribe, who would rear on an average a greater
number of children, did not after the lapse of many gen-
erations modify to a certain extent the character of the
tribe.

With our domestic animals, when a foreign breed is
introduced into a new country, or when a native breed is
long and carefully attended to, either for use or ornament,
it is found after several generations to have undergone,
whenever the means of comparison exist, a greater or less
amount of change. This follows from unconscious selec-
tion during a long series of generations — that is, the pres-
ervation of the most approved individuals — without any
wish or expectation of such a result on* the part of the
breeder. So, again, if two careful breeders rear during
many years animals of the same family, and do not com-
pare them together or with a common standard, the ani-
mals arc found after a time to have become, to the surprise
of their owners, slightly dillbreiit." Each breeder lias im-
pressed, as Von Nathusius well expresses it, the character
of his own mind — his own taste and judgment — OH his
animals. What reason, then, can he assigned why similar
results should not follow from the long-continued selection
of the most, admired women by thO80 men of r:n h tribe

H*Ths Variation of Animulrt uml IMantn uiulur Domi'stuvition,' vol.
KL pp. 810-217.

354

SEXUAL SELECTION: MAN.

[Taut II.

who were able to rear to maturity the greater number of
children? This wotdd 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, in which some
form of marriage was practised, to spread over an unoc-
cupied continent; they would soon split up into distinct
hordes, which would be separated from each otkea l»v
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 conic 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 aiu\ leading savages
preferring certain women to others. Thus the difference!
between the tribes, at first very slight, would gradually
and inevitably be increased to a greater and greater
degree.

"With animals in a state of nature, many character!
proper to the males, such as size, strength, special w< apons,
courage and pugnacity, have been acquired through 1 1 1 « -
law of battle. The semi-human progenitors of man, like
their allies the Quadrumana, will almost certainly have
been thus modified; and, as savages still tight f«»r the pos-
session of their women, a similar process of selection has
probably gone on in a greater or less degree to the present
dav. Other characters proper to the males of the lower

" An ingenious writer argues, from a comparison of the pictures of
Raphael, Rubens, and modern French artists, that the idea of beauty it
not absolutely the same even throughout Europe i see the 'Lbes of

Haydn and Mozart/ by M. Pombet, Eng. transit, p. 278.

Chap. XX.]

MANNER OF A-CTION.

355

animals, such as bright colors and various ornaments, have
been acquired by the more attractive males having been
preferred by the females. There are, however, exceptional
cases in which the males, instead of having been the se-
lected, have been the selectors. We recognize such cases
by the females having been rendered 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, namely, with the Rhesus monkey.

Man is more powerful in body and mind than woman,
and in the savage state he keeps her in a far more abject
state of bondage than does the male of any other animal;
therefore it is not surprising that he should have gained
the power of selection. Women are everywhere conscious
of the value of their beauty; and when they have the
means, they take more delight in decorating themselves
with all sorts of ornaments than do men. They borrow
the plumes of male birds, with which Nature decked this
sex iu order to charm the females. As women have loBff
been selected for beauty, it is not surprising that some of
the successive variations should have been transmitted in
a limited manner ; and consequently that women should
have transmitted their beauty in a somewhat higher degree
to their female than to their male offspring. Hence women
have become more beautiful, :is most persons will admit,
than men. Women, however, certainly transmit most of
their characters, including beauty, to their offspring of both
sexes; so that the continued preference by the men of
each race of the more attractive Women, according to their
Standard <>f taste, would tend to modify in the same man-
ner all the individuals of both sexes belonging to the
race.

With respect to the other form of sexual Belootion
(which with the lower animals ismuoh the most common),

35G SEXUAL SELECTION: MAX. £Pajit 1 1 .

namely, when the females are the selectors, and accept
only those males which excite or charm them most, wo
have reason to believe that it formerly acted on the pro-
genitors of man. Man in all probability owes his beard,
and perhaps some other characters, to inheritance from an
ancient progenitor who gained, in this manner his orna-
ments. But this form of selection may have occasional!)
acted during later times ; for in utterly barbarous tribes
the women have more power in choosing, rejecting, and
tempting their lovers, or of afterward changing tkeil hat-
bands, than might have been expected. As this is a point
of some importance, I will give in detail such evM ism
I have been able to collect.

Ilearne describes how a woman in one of the tril
Arctic America repeatedly ran away from her huftbtfl I
and joined a beloved man ; and with the Charruas of South
America, as Azara states, the power of divorce isperfe* tly
free. With the Abipones, when a man chooses a wife he
bargains with the parents about the price. But, " it fre-
quently ^happens that the girl rescinds what has been
agreed upon between the parents and the bridegroom,
obstinately rejecting the very mention of marriage.'7 She
often runs away, hides herself, and thus eludes the bride-
groom. 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 pro-
tect her; if, however, she is satisfied, the matter is settled
forthwith." InTierra del Fuegoayoung man first obtains
the consent of the parents by doing them some service, ami
then he attempts to carry off* the girl; "but if si r is un-
willing, she hides herself in the woods until her admirer
heartily tired of looking for her, and gives up the pursuit;
but this seldom happens." "With the Calmucks there is a
regular race between the bride and bridegroom, the 1 >i-

Chap. XX.]

MANNER OF ACTION.

357

mer 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." So with the wild tribes of the
Malay archipelago there is a similar racing-match ; and it
appears from M. Bourien's account, as Sir J. Lubbock re-
marks, 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."

Turnir g to Africa: the Kaffres buy their wives, and
girls arc severely beaten by their fathers if they will not
accept a chosen husband;. yet it is manifest from many
facts given by the Rev. Mr. Shooter, that they have con-
siderable power of choioe. Thus very ugly, though rich
men, have been known to fail in getting wives. The girls,
before consenting to be betrothed, compel the men to show
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 favored lover.
With the degraded Bushwomen of South Africa, " when
a girl has grown up to womanhood without having* been
betrothed, which, however, does not often happen, her
lover must gain her approbation, as well as that of the
parents." 18 Mr. Winwood Reade made inquiries for me
with respect to the negroes of \yestcrn Africa, and he in-
forms me that " the women, at least among the more in-
telligent pagan tribes, have no difficulty in getting the
husbands whom they may desire, although it is considered
unwomanly to ask a man to marry them. They are quite

™ J znra, * Voyages,' etc. torn. ii. p. 23. Dobrizhoffer, 'An account
of the Abiponcs,' vol. ii. 1822, p. 207. Williams on the Fiji Islanders,
uS quotf'l by Lubbock, 'Origin of Civilization,' ]N7(>, p. 7'J. On (ho
Fucgiann, King and Fit/. Hoy, 'Voyages of the Adventure and Beaglif
vol. ii. lH'W, p. 182. On tho Culmucks, quoted by Mi mian, ' Primi-
tive Man ig«-,' I H t r» , p. On the Malays Lubbock, ihi.l. p. 7f,. 'flit'

Rev. J. Shooter, 'On tho Kafirs of Natal,' 1857,' pp. 62-00. On the
Dmhwomen, Hurchcll, 1 Travels in Smith Africa,' vol. ii. 1821, p. 5U.

358

SEXUAL SELECTION: MAN.

[Part II.

capable of falling in love, and of forming tender, passion-
ate, and faithful attachments."

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 dis-
like, either before or after marriage. Preference on the
part of the women, steadily acting in any one direc-
tion, would ultimately affect the character of the tribe ;
for the women would generally choose not merely the
handsomer men, according to their standard of taste, but
those who were at the same time best able to defend and
support them. Such well-endowed pairs would commonly
rear a larger number of offspring than the less well en-
dowed. 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 these two forms of selection
seem actually to have occurred, whether or not simulta-
neously, with mankind, especially during the earlier pe-
riods of our long history.

We will now consider in a little more detail, relatively
to sexual selection, some pf the characters which distin-
guish the several races of man from each other and from
the lower animals, namely, the more or less complete ab-
sence of hair from the body and the color of the skin.
We need say nothing about the great diversity in the
shape of the features and of the skull between the differ-
ent races, as we have seen in the last chapter how differ-
ent is the standard of beauty in these respects. These
characters will therefore probably have been acted on
through sexual selection ; but we have no means of judging,
as far as I can see, whether they have been acted on
chiefly through the male or female side. The musical
faculties of man have likewise been already discussed.

Chap. XX.]

ABSENCE OF HAIR.

359

A bsence of Hair on the Body, and its Development on
the Face and Head. — From the presence of the woolly
hair or lanugo on the human foetus, and of rudimentary
hairs scattered over the body during maturity, we may
infer that man is descended from some animal which was
born hairy and remained so during life. The loss of hair
is an inconvenience and probably an injury to man even
under a hot climate, for he is thus exposed to sudden
cl ills, 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 cover-
ing. No one supposes that the nakedness of the skin is
any direct advantage to man, so that his body cannot have
been divested of hair through natural selection.19 Nor
ha e we any grounds for believing, as shown in a for-
mer chapter, that this can be due to the direct action of the *
conditions to which man has long been exposed, 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 rea-

19 'Contributions to the Theory of Natural Selection,' 1870, p. 34G.
Mr. Wallace believes (p. 350) " that some intelligent power has guided
or determined the development of man ; " and he considers the hair-
less condition of the skin as coming under this head. The Rev. T. EL
Stcbbing, in commenting on this view (' Transactions of Devonshire
Assoc. for Science,' 1870) remarks that, had Mr. Wallace "employed
hi iMia\ ingenuity on the question of man's hairless skin, he might havo
Been the possibility of its selection through its superior beauty or the
health attaching to superior cleanliness. At any rate it is surprising
that ho should picture to himself a superior intelligence plucking tho
hair ffom the backs of savage men (to whom, according to his own ac-
count, it would have been useful and beneficial), in order that the de-
scendants of the poor shorn wretches might, after many deaths from cold
and damp in the course of many generations," have been forced to raiso
Hum elves in tin? scale of civilization through the practice of various
arts, in the manner indicated by Mr. Wallace,

3G0

SEXUAL SELECTION: MAN.

[Taut II.

sonably suspect that this is a character which has been
gained through sexual selection. We know that the faces
of several species of monkeys, and large surfaces at the pos-
terior end of the body in other species, have been denuded
of hair ; and this we may safely attribute to sexual selec-
tion, for these surfaces are not only vividly colored, but
sometimes, as with the male mandrill and female rhesus,
much more vividly in the one sex than in the other. As
these animals gradually reach maturity the naked surfaces,
as I am informed by Mr. Dartlett, grow larger, relatively
to the size of their bodies. The hair, however, appears to
have been removed in these cases, not for the sake of nu-
dity, but that the color of the skin should be more fully
displayed. So, again, with many birds the head and
neck have been divested of feathers through sexual
•selection, for the sake of exhibiting the brightly-colored
skin.

As woman has a less hairy body than man, and as
this character is common to all races, we may conclude
that our female semi-human progenitors were probably
first partially divested of hair; and that this occurred at
an extremely remote period before the several races had
diverged from a common stock. As our female progeni-
tors gradually acquired this new character of nudity, they
must have transmitted it in an almost equal degree to
their young offspring of both sexes ; so that its transmis-
sion, as in the case of many ornaments with mammals and
birds, has not been limited either by age or sex. There is
nothing surprising in a partial loss of hair having been
esteemed as ornamental by the ape-like progenitors of
man, for we have seen that with animals of all kinds in-
numerable strange characters have been thus esteemed,
and have consequently been modified through sexual
selection. Nor is it surprising that a character in a slight
degree injurious should have been thus acquired ; for we

Chap. XX.]

ABSENCE OF HAIR.

3G1

know that this is the case with the plumes of some birds,
and with the horns of some stags.

The females of certain anthropoid apes, as stated in a
former chapter, are somewhat less hairy on the under sur-
face than are the males; and here we have what might
have afforded a commencement for the process of denu-
dation. 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. Hence the King
of Sbm had to bribe a man to marry the first hairy wom-
an in the family, who transmitted this character to her
young offspring of both sexes.20

Some races are much more hairy than others, espe-
cially on the male side ; but it must not be assumed that
the more hairy races, for instance Europeans, have re-
tained a primordial condition more completely than have
the naked races, such as the Calmucks or Americans. It
is a more probable view that the hairiness of the former
is due to partial reversion, for characters which have long
been inherited arc always apt to return. It does not ap-
pear that a cold climate has been influential in h ading to
this kind of reversion; excepting perhaps with the ne-
groes, who have been reared during several generations,
in the United Slates," and possibly with the Ainos, wh<>

50 ' The Variation of Animals ami Plants under Domestication,' vol. ii.
IHoR, p. 327.

Investigations into Military and Anthropological Stati.-ties of
American Soldiers,' by It. A. (iould, INC.'.I; p. r>f,s : Ol, ervations were
carefully made on the pilosity of 2,129 black and colored soldier*, while
they were bathing • and, by looking to the published table, " il is mani-
fest at a glance that there is but little, if any, dihVrcnce between (he
White and the black races in this renpect." Ii is, howi v< r, e< Main that
negroes in tln ir native and much hotter land of Africa, have icmurkably

:i5

302

SEXUAL SELECTION: MAN.

[Pakt IL

inhabit the northern islands of the Japan archipelago.
But the laws of inheritance are so complex that we can
seldom understand their action. If the greater hairiness
of certain races be the result of reversion, unchecked by
any form of selection, the extreme variability of this char-
acter, even within the limits of the same race, ceases to be
remarkable.

"With respect to the beard, if we turn to our best
guide, namely the Quadrumana, we find beards equally
well developed in both sexes of many species, but in
others, 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 colors, of
the hair about the heads of many monkeys, it is highly
probable, as before explained, that the males first ac-
quired their beards as an ornament through sexual selec-
tion, transmitting them in most cases, in an equal or near-
ly equal degree, to their offspring of both sexes. We
know from Eschricht 91 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 a progenitor of which both sexes
were bearded. It appears therefore at first sight prob-
able that man has retained his beard from a very early
period, while woman lost her beard at the same time
when her body became almost completely divested of
hair. Even the color of the beard with mankind seems to

smooth bodies. It should be particularly observed that pure blacks
and mulattoes were included in the above enumeration ; and this is an
unfortunate circumstance, as in accordance with the principle, the truth
of which I have elsewhere proved, crossed races would be eminently
liable to revert to the primordial hairy character of their early ape-like
progenitors.

w " Ueber die itichtung der Ilaarc am Menscblichen Korper," in
Muller's « Archiv fur Anat und Phys.' 1837, b. 40.

Chap. XX.]

BEARDS.

363

have been inherited from an ape-like progenitor ; for when
there is any difference in tint between the hair of the head
and the beard, the latter is lighter colored in all monkeys
and in man. There is less improbability in <;he men of
the bearded races having retained their beards from pri-
mordial times, than in the case of the hair on the body ;
for with those Quadrumana, in which the male has a
larger beard than that of the female, it is fully developed
only at maturity, and the later stages of development
may have been exclusively transmitted to mankind. Wo
should then see what is actually the case, namely, our
male children, before they arrive at maturity, as destitute
of beards as are our female children. On the other hand,
the great variability of the beard within the limits of the
same race and in different races indicates that reversion
has come into action. However this may be, we must
not overlook the part which sexual selection may have
played even during later times ; for we know that, witli
savages, the men of the beardless races take infinite pains
in eradicating every hair from their faces, as something
odious, while the men of the bearded races feel the
greatest pride in their beards. The women, no doubt,
participate in these feelings, and if so sexual selection can
hardly have failed to have effected something in the
course of later times."

23 Mr. Sproat ('Scene* and Studies of Savage Life,' 18C8, p. 25) smg-
gestg, with reference to the beardless natives of Vancouver's Island, that
the custom of plucking oat the hairs on the face, " continued from one
generation to another, would perhaps at last produce a race distinguish
able DJ a thin and Btraggling growth of beard." Hut the custom would
not have arisen until the beard had already become, from some inde-
pendent cause, greatly reduced. Nor have we any direct evidence that
the continued eradication of the hair would lead to any Inherited elVect.
Owing to this cause of doubt, I have not hitherto alluded to the belief
held by some distinguished ethnologists, for instance M. (losse of (icne-
va, that artificial modifications of the skull tend to In- inherited. 1 ha\e

3C4

SEXUAL SKLKCTIOX : MAX.

[Paiit II.

It is rather difficult to form a judgment how the long
hair on our heads became developed. Eschricht 24 states
that in the human foetus the hair on the face during the
fifth month is longer than that on the head; and this in-
dicates that our semi-human progenitors were not fur-
nished with long tresses, which consequently must have
been a late acquisition. This is likewise indicated by the
extraordinary difference in the length of the hair in the
different races; in the negro the hair forms a mere curly
mat ; with us it is of great length, and with the American
natives it not rarely reaches to the ground. Some species
of Semnopitheeus have their heads covered with moder-
ately long hair, and this probably serves as an ornament
and was acquired through sexual selection. The same
view may be extended to mankind, for we know that long
tresses are now and were formerly much admired, as may
be observed in the works of almost every poet ; St. Paul
says, " If a woman have long hair, it is a glory to her ; "
and we have seen that in North America a chief was
elected solely from the length of his hair.

Color of the Skin. — The best kind of evidence that
the color of the skin has been modified through sexual
selection is wanting in the case of mankind ; for the sexes
do not differ in this respect, or only slightly and doubt-
fully. On the other hand, we know from many facts al-
ready given that the color of the skin is regarded by the
men of all races as a highly-important element in their
beauty; so that it is a character which would be likely to
be modified through selection, as has occurred in innumcr-

no wish to dispute this conclusion ; and we now know from Dr. Brown-
S6quard's remarkable observations, especially those recently communi-
cated (1870) to the British Association, that with guinea-pigs the effect*
of operations are inherited.

u 4 Ueber die Richtung,1 ibid. 8. 40.

Chap. XX.]

SUMMARY.

365

able instances with the lower animals. It seems at first
sight a monstrous supposition that the jet blackness of
the negro has been gained through sexual selection ; but
this view is supported by various analogies, and we know
that negroes admire their own blackness. With mam-
mals, when the sexes differ in color, 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 shall be transmitted to both sexes or to one
alone. The resemblance of JPithecia satanas with his jet-
black skin, white rolling eyeballs, and hair parted on the
top of the head, to a negro in miniature, is almost ludi-
crous.

The color of the face differs much more widely in the
various kinds of monkeys than it does in the races of
man ; and we have good reason to believe that the red,
blue, orange, almost white and black tints of their skin,
even when common to both sexes, and the bright colors
of their fur, as well as the ornamental tufts of hair about
the head, have all been acquired through sexual selection.
As the newly-born infants of the most distinct races do
not differ nearly as much in color as do the adults, al-
though their bodies arc completely destitute of hair, we
have some slight indication that the tints of the different
races were acquired subsequently to the removal of the
hair, which, as before stated, must have occurred at a
very early period.

Summary. — We may conclude that the greater size,
st length, courage, pugnacity, and even energy of man, in

comparison with the same qualities in woman, were :ie-
quired during primeval times, and have subsequently boon
augmented, chiefly through the contests of miloi tot

the possession of the females. The greater Intellectual
vigor ami power <>!' invention in man arc probably due t«>

3GG

SEXUAL SELECTION: MAN.

[Part II.

natural selection combined with the inherited effects of
habit, for the most able men will have succeeded best in
defending and providing for themselves, their wives and
offspring. As far as the extreme intricacy of the subject
permits us to judge, it appears that our male ape-like pro-
genitors acquired their beards as an ornament to charm or
excite the opposite sex, and transmitted them to man as
he now exists. The females apparently were first de-
nuded of hair in like manner as a sexual ornament; but
they transmitted this character almost equally to both
sexes. It is not improbable that the females were modi-
fied in other respects for the same purpose and through
the same means ; so that women have acquired sweeter
voices and become more beautiful than men.

It deserves "particular attention that with mankind all
the conditions for sexual selection were much more favor-
able, during a very early period, when man had only just
attained to the rank of manhood, than during later times.
For he would then, as we may safely conclude, have been
guided more by his instinctive passions, and less by fore-
sight or reason. lie would not then have been so utterly
licentious as many savages now arc ; and each male would
have jealously guarded his wife or wives. He would not
then 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 con-
cerned, in chief part during 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 ob-
tained 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 scien-

Chap. XX.J

SUMMARY.

367

tific precision. He who does not admit this agency in
the case of the lower animals, will properly 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 shown that
the races of man differ from each other and from their
nearest allies among the lower animals, in certain charac-
ters which are of no service to them in their ordinary
habits of life, and which it is extremely probable would
have been modified through sexual selection. We have
seen that with the lowest savages the people of each tribe
admire their own characteristic qualities — the shape of the
head and face, the squareness of the cheek-bones, the
prominence or depression of the nose, the color 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, etc. Hence these and other such points could
hardly fail to have been slowly and gradually exagger-
ated from the more powerful and able men in each tribe,
who would succeed in rearing the largest number of off-
spring, having selected during many generations as their
wives the most strongly-characterized and therefore most
attractive women. For my own part I conclude that of
all the causes which have led to the differences in exter-
nal appearance between the races of man, and to a certain
extent between mnn and the lower animals, sexual selec-
tion has been by far the most efficient.

3C8

GENERAL SUMMARY

[Part II.

CHAPTER XXL
General Summary and Conclusion.

Main Conclusion that Man is descended from some Lower Form. — Man-
ner of Development. — Genealogy of Man. — Intellectual and Mural
Faculties. — 8exual Selection. — Concluding Remarks.

A brief summary will here be sufficient to recall to
the reader's mind the more salient points in this work.
Many of the views which have been advanced arc 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 long endure ;
but false views, if supported by some evidence, do little
harm, as every one takes a salutary pleasure in proving
their falseness ; and when this is done, one path toward
error is closed, and the road to truth is often at the same
time opened.

The main conclusion arrived at in this work, and now
held by many naturalists who arc well competent to form
a sound judgment, is that man is descended from some
less highly-organized form. The grounds upon which this
conclusion rests will never be shaken, for the close simi-
larity between man and the lower animals in embryonic
development, as well as in innumerable points of structure

Chap. XXL] AND CONCLUDING REMARKS.

369

and constitution, both of high and of the most trifling im-
portance— the rudiments which he retains, and the abnor-
mal reversions to which he is occasionally liable — are facts
which cannot be disputed. They have long been known,
but until recently they told us nothing with respect to
the origin of man. Now, when viewed by the light of
our knowledge of the whole organic world, their meaning'
is unmistakable. The great principle of evolution stands
up clear and firm, when these groups of facts are consid-
ered in connection with others, such as the mutual affini-
ties 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 sav-
age, 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 re-
semblance of the embryo of man to that, for instance, of
a dog — the construction of his skull, limbs, and whole
frame, independently of the uses to which the parts may
be put, on the same plan with that of other mammals —
the occasional reappearance of various structures, for in-
stance, of several distinct muscles, which man does not
normally possess, but which are common to the Quadru-
mana — and a crowd of analogous facts — all po'mt in the
plainest manner to the conclusion that man is the co-de-
scendant with other mammals of a common progenitor.

We have seen that man incessantly presents individual
differences in all parts of his body and in his mental facul-
ties. These differences or variations seem to be induced

by the same general causes, and lo obey the same laws :is

with the lower animals. In both oases similar lain of
inheritance prevail. Man tends to increase at a greater
rate than his means of subsistence j consequently lie is

occasionally subjected t<» a severe struggle l'<»r existence,

370 GENERAL SUMMARY [PaW-H.

and natural selection will have effected whatever lies with-
in its scope. A succession of strongly-marked variations
of a similar nature arc by no means requisite ; slight
fluctuating differences in the individual suffice for the
work of natural selection. \Vc 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, will be long inher-
ited. When one part is modified, other parts will change
through the principle of correlation, of which we have in-
stances 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 abun-
dant food, heat, or moisture ; and lastly, many characters
of slight physiological importance, some indeed of con-
siderable importance, have been gained through sexual
selection.-

No doubt man, as well as every other animal, presents
structures which, as far as we can judge with our little
knowledge, are not now of any service to him, nor have
been so during any former period of his existence, either
in relation to his general conditions of life, or of one sex
to the other. Such structures cannot be accounted for
by any form of selection, or by the inherited effects of the
use and disuse of parts. We know, however, that many
strange and strongly - marked peculiarities of structure
occasionally appear in our domesticated productions, and
if the unknown causes which produce them 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 occa-
sional modifications, especially through the study of mon-
strosities : hence the labors of experimentalists, such as
those of M. Camille Dareste, are full of promise for tho

Chap. XXL] AND CONCLUDING REMARKS.

371

future. In the greater number of cases, we can only say
that the cause of each slight variation and of each mon-
strosity lies much more in the nature or constitution of
the organism, than in the nature of the surrounding con-
ditions ; though new and changed conditions certainly
play an important part in exciting organic changes of all
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 man-
hood, he has diverged into distinct races, or, as they may
be more appropriately called, subspecies. Some of these,
for instance, the Negro and European, arc 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. Neverthe-
less all the races agree in so many unimportant details of
structure and in so many mental peculiarities, that these
can be accounted for only through inheritance from a com-
mon progenitor; and a progenitor thus characterised
would probably have deserved to rank as man.

It must not be supposed that the divergence of each
race from the other races, and of all the races from a com-
mon stock, can be traced back to any one pair of progeni-
tors. On the Contrary, at every stage in the process of
modification, all the individuals which were in any way

best fitted for their conditions of life, though in different

degrees, would have survived in greater numbers than llie

less well fitted. The process would have been like that
followed by man, when lie does not intentionally select,
particular individuals, hut breeds from all the superior
and neglects all the inferior individuals. He thus ilowH

but surely modifies liis stock, and uneonseiousU forms :i

new strain. S-. wiih respect to modifications, acquired
Independent! j <>i selection, and due to variations arising

372

GENERAL SUMMARY

[Part II.

from the nature of the organism and the action of the sur-
rounding conditions, or from changed habits of life, no
single pair Avill have been modified in a much greater de-
gree than the other pairs which inhabit 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 ap-
proximately place them in their proper position in the
zoological series. We thus learn that man is descended
from a hairy quadruped, furnished with a tail and pointed
ears, probably aboreal in its habits, and an inhabitant of
the Old World. This creature, if its whole structure had
been examined by a naturalist, would have been classed
among the Quadrumana, as surely as would the common
and still more ancient progenitor of the Old and New
World monkeys. The Quadrumana and all the higher
mammals nre probably derived from an ancient marsupial
animal, and this through a long line of diversified forms,
either from some reptile-like or "some amphibian-like crea-
ture, and this again from some fish-like animal. In the
dim obscurity of the past we can see that the early pro-
genitor of all the Vertebrata must have been an aquatic
animal, provided with branchiae, with the two sexes united
in the same individual, and with the most important
organs of the body (such as the brain and heart) imper-
fectly developed. This animal seems to have been more
like the larva) of our existing marine Ascidians than any
other known form.

Tlie greatest difficulty which presents itself, when we
are driven to the above conclusion on the origin of man,

Chap. XXL] AND CONCLUDING REMARKS.

373

is the high standard of intellectual power and of moral
disposition which he has attained. But every one who
admits the general principle of evolution, must see that
the mental powers of the higher animals, which are the
same in kind with those of mankind, 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. The development of these powers in animals *
does not offer any special difficulty ; for with our domesti-
cated animals, the mental faculties are certainly variable,
and the variations are inherited. No one doubts that
these faculties are of the utmost importance to animals in
a state of nature. Therefore the conditions are favorable
for their development through natural selection. The
same conclusion may be extended to man ; the intellect
must have been all-important to him, even at a very
remote period, enabling him to use language, to invent
and make weapons, tools, traps, etc. ; by which means, in
combination with his social habits, he long ago became
the most dominant of all living creatures.

A great stride in the development of the intellect will
have followed, as soon as, through a previous considerable
advance, the half-art and half-instinct of language camo
into use ; for the continued use of language will have re-
acted on the brain, and produced an inherited effect ; and
this again will have reacted on the improvement of lan-
guage. The large size of the brain in man, in comparison
with that of the lower animals, relatively to the size of
their bodies, may be attributed in chief part, as 3lr.
Chauncey Wright has well remarked,1 to the early 086 of
some simple form of language— that wonderful engine

which affixes signs to all sorts of objects and qualities,

1 <)n the " Limita of Natural Selection," in the ' N<>itii ixnerlotn R*
vi.Mv,' Oei into, p. 295.

374

GENERAL SUMMARY

[Part II.

and excites trains of thought which would never arise
from the mere impression of the senses, and if they did
arise could not be followed out. The higher intellectual
powers of man, such as those of ratiocination, abstraction,
self-consciousness, etc., will have followed from the con-
tinued improvement of other mental faculties; but with-
out considerable culture of the mind, both in the race and
in the individual, it is doubtful whether these high powers
would be exercised, and thus fully attained.

The development of the moral qualities is a more in-
teresting and difficult problem. Their foundation lies in
the social instincts, including in this term the family ties.
These instincts are of a highly-complex nature, and in the
case of the lower animals give special tendencies toward
certain definite actions ; but the more important elements
for us are love, and the distinct emotion of sympathy.
Animals endowed with the social instincts take -pleasure
in each other's company, warn each other of danger, de-
fend and aid each other in many ways. These instincts
are not extended to all the individuals of the species, but
only to those of the same community. As they are high-
ly beneficial to the species, they have in all probability
been acquired through natural selection.

A moral being is one who is capable of comparing his
past and future actions and motives — of approving of
some and disapproving of others ; and the fact that man
is the one being who with certainty can be thus desig-
nated makes the greatest of all distinctions between him
and the lower animals. But in our third chapter I have
endeavored to show that the moral sense follows, firstly,
from the enduring and always present nature of the
social instincts, in which respect man agrees with the
lower animals ; and secondly, from his mental faculties
being highly active and his impressions of past events
extremely vivid, in which respects he differs from the

Chap. XXL] AND CONCLUDING REMARKS.

375

lower animals. Owing to this condition of mind, man
cannot avoid looking backward and comparing the im-
pressions of past events and actions. He also continually
looks forward. Hence after some temporary desire or
passion has mastered his social instincts, he will reflect
and compare the now weakened impression of such past
impulses with the ever-present social instinct ; and he
will then feel that sense of dissatisfaction which all unsat-
isfied instincts leave behind them. Consequently he re-
solves to act differently for the future — and this is con-
science. Any instinct which is 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 partly impelled by a wish to aid the
members of the same community in a general manner,
but more commonly to perform certain definite actions.
Man is impelled by the same general wish to aid Lis
fellows, but has few or no special instincts. He differs
also from the lower animals in being able to express his
desires by words, which thus become the guide to the aid
required and bestowed. The motive to give aid is like-
wise somewhat modified in man: it no longer consists
solely of a blind instinctive impulse, but is largely intlu-
enced by the praise or blame of his fellow-men. lioth
ili<- appreciation and the bestowal of praise and blame
rest <>n Sympathy ; and this emotion, as we have Been, is
oik; of the most important elements of the social instincts.
Sympathy, though gained as an instinct, is also much
Itrengthened by exercise or habit. As all men desire

their owe happiness, praise or blame is bestowed on

actions and motives, according ;is I hey lead to this end ;

GENERAL SUMMARY

[Part EL

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 reason-
ing powers advance and experience is gained, the more
remote effects of certain lines of conduct on the character
of the individual, and on the general good, are perceived ;
and then the self-regarding virtues, from coming within
the scope of public opinion, receive praise, and their
opposites receive blame. But with the less civilized
nations reason often errs, and many bad customs and base
superstitions come within the same scope, and consequent-
ly are esteemed as high virtues, and their breach as heavy
crimes.

The moral faculties are generally esteemed, and with
justice, as of higher value than the intellectual powers.
But we should always bear in mind that the activity of
the mind in vividly recalling past impressions is one of
the fundamental though secondary bases of conscience.
This fact affords the strongest argument for educating
and stimulating in all possible ways the intellectual fac-
ulties of every human being. No doubt a man with a
torpid mind, if his social affections and sympathies are
well developed, will be led to good actions, and may have
a fairly sensitive conscience. But whatever renders the
imagination of men more vivid and strengthens the habit
of recalling and comparing past impressions, will make
the conscience more sensitive, and may even compensate
to a certain extent for weak social affections and sym-
pathies.

The moral nature of man has reached the highest
standard as yet attained, partly through the advance-
ment of the reasoning powers and consequently of a just
public opinion, but especially through the sympathies
being rendered more tender and widely diffused through
the effects of habit, example, instruction, and reflection

Chap. XXL] AND CONCLUDING EEMARKS.

377

It is not improbable that virtuous tendencies may through
long practice be inherited. With the more civilized races,
the conviction of the existence of an all-seeing Deity has
had a potent influence on the advancement of morality.
Ultimately man no longer accepts the praise or blame of
his fellows as his chief guide, though few escape this influ-
ence, but his habitual convictions controlled by reason
afford him the safest rule. His conscience then becomes
his supreme judge and monitor. Nevertheless the first
foundation or origin of the moral sense lies in the social
instincts, including sympathy ; and these instincts no
doubt were primarily gained, as in the case of the lower
animals, through natural selection.

The belief in God has often been advanced as not only
the greatest, but the most complete, of all the distinctions
between man and the lower animals. It is, however, im-
possible, 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 the
reasoning powers of man, 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 exist-
ence. But this is a rash argument, as we should thus be
compelled to believe in the existence of many cruel and
malignant spirits, possessing only a little more power
than man ; for the belief in them is far more general than
of a beneficent Deity. The idea of a universal and benefi-
cent Creator of the universe does not seem to arise in (he
mind of man, until he has been elevated by long-continued

culture.

lie who believes in (he advancement Of man from some
lowly-Organized form, will naturally ask, "How does this

378

GENERAL SUMMARY

[Part II.

bear on the belief in the immortality of the soul ? " The
barbarous races of man, as Sir J. Lubbock has shown,
possess no clear belief of this kind; but arguments de-
rived 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 the minute germinal vesicle to the child
either before or after birth, man becomes an immortal
being ; and there is no greater cause for anxiety because
the period in the gradual] y-ascending organic scale cannot
possibly be determined.2

1 am aware that the conclusions arrived at in this work
will be denounced by some as highly irreligious; but he
who thus denounces them is bound to show wiry 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 con-
clusion, 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
these volumes ; for, as I have attempted to show, it lias
played an important part in the history of the organic
world. As summaries have been given to each chapter,
it would be superfluous here to add a detailed summary.

2 The Rev. J. A. Picton gives a discussion to tbis effect in bis ' New
Theories and the Old Faith,' 1870.

Chap. XXL] AND CONCLUDING REMARKS.

379

I am aware that much remains doubtful, but I have
endeavored 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 two sexes
combined in the same individual, or, what is still more im-
portant, 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 ; and it deserves notice that
we here find the intellectual faculties developed, but in
two very distinct lines, to the highest standard, namely,
in the Hymenoptera (ants, bees, etc.) among the Arthro-
poda, and in the Mammalia, including man, among the
Vertebrata.

In the most distinct classes of the animal kingdom,
with mammals, birds, reptiles, fishes, insects, and even
crustaceans, the differences between the sexes follow al-
most exactly the same rules. The males are almost
always the wooers ; and they alone are armed with
special weapons for fighting with their rivals. They are
generally stronger and larger than the females, and are
endowed with the requisite qualities of courage and pug-
nacity. They are provided, either exclusively or in a
much higher degree than the females, with organs for pro-
ducing vocal or instrumental music, and with odoriferous
glands. They an; ornamented with infinitely-diversified
appendages, and with the most brilliant or conspicuous
colors, often arranged in elegant patterns, while the fe-
males arc left unadorned. When the sexe.* differ in more
important structures, it is the male which is provided with
special sense-organs for discovering (he female, with loco-
motive organs for reaching her, and oil en with prehensile

9

380

CEXEKAL SUMMARY

[Part II.

organs for holding lier. These various structures for
securing or charming the female arc often developed in
the male during only part of the year, namely, the brccd-
ing-season. They have in many cases been transferred in
a greater or less degree to the females ; and in the tatter
case they appear in her as mere rudiments. They are lost
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 resembles her young offspring throughout
life. In almost every great class a few anomalous cases
occur in which there has been an almost complete trans-
position of the characters proper to the two sexes ; the fe-
males 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 throughout all the higher divisions of the animal
kingdom of one common cause, namely, sexual selection.

Sexual selection depends on the success of certain in-
dividuals over others of the same sex in relation to the
propagation of the species; while natural selection de-
pends 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 male sex, in order to drive
away or kill their rivals, the females remaining passive;
while, in the other, the struggle is likewise between the
individuals of the 6ame sex, in order to excite or charm
those of the opposite sex, generally the females, which no
longer remain passive, but select the more agreeable part-
ners. This latter kind of selection is closely analogous to
that which man unintentionally, yet effectually, brings to
bear on his domesticated productions, when he continues

Chap. XXL]

AND CONCLUDING REMARKS.

381

for a long -time choosing the most pleasing or useful indi-
viduals, without any wish to modify the breed.

The laws of inheritance determine whether characters
gained through sexual selection by either sex shall be
transmitted to the same sex, or to both sexes ; as well as
the age at which they shall be developed. It appears
that variations which arise late in life are commonly trans-
mitted to one and the same sex. Variability is the neces-
sary basis for the action of selection, and is wholly inde-
pendent of it. It follows from this, that variations of the
same general nature have often been taken advantage of
and accumulated through sexual selection in relation to
the propagation of the species, and through natural selec-
tion 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 modifica-
tions acquired through sexual selection are often so
strongly pronounced that the two sexes have frequently
been ranked as distinct species, or even as distinct genera.
Such strongly-marked differences must be in some manner
highly important; and we know that they have been
acquired in some instances at the cost not only of incon-
venience, but of exposure to actual danger.

The belief in the power of sexual selection rests ehielly
on the following considerations: The characters which
we have the best reason for supposing to have been thus
acquired are confined to one sex; and this alone renders
it probable that they are in some way connected with the
act of reproduction. These characters in innumerable in-
stances an; fully developed only at, maturity J ami often
(hiring only a part of the year, which is alwa\s the breed-
ing-season. The males (passing over a few exceptional
cases) are the most, active in OOUrUhip J tlwy are tin* best
armed, and are rendered the most attracti\e in various

382 GENERAL SUMMARY [Part II.

ways. It is to be especially observed that the males dis-
play 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 display should be purposeless. Lastly, we have
distinct evidence with some quadrupeds and birds that the
individuals of the one sex are capable of feeling a strong
antipathy or preference for certain individuals of the oppo-
site sex.

Bearing these facts in mind, and not forgetting the
marked results of man's unconscious selection, 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, characterized in some
peculiar manner, the offspring would slowly but surely
become modified in this same manner. I have not at-
tempted to conceal that, excepting when the males are
more numerous than the females, or when polygamy pre-
vails, it is doubtful how the more attractive males succeed
in leaving a larger number of offspring to inherit their
superiority in ornaments or other charms than the less
attractive males ; but I have shown that this would prob-
ably follow from the females — especially the more vigor-
ous females, which would be the first to breed — preferring
not only the more attractive but at the same time the
more vigorous and victorious males.

Although we have some positive evidence that birds
appreciate bright and beautiful objects, as with the Bower-
birds of Australia, and although they certainly appreciate
the power of song, yet I fully admit that it is an astonish-
ing fact that the females of many birds and some mam-
mals should be endowed with sufficient taste for what has
apparently been effected through sexual selection ; and
this is even more astonishing in the case of reptiles, fish,
and insects. But we really know very little about the

Chap. XXL]

AND CONCLUDING REMARKS.

383

minds of the lower animals. It cannot be supposed that
male Birds of Paradise or Peacocks, for instance, should
take so much 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, namely, that several peahens, when
debarred from an admired male, remained widows during
a whole season rather than pair with another bird.

Nevertheless, I know of no fact in natural history more
wonderful than that the female Argus pheasant should be
able to 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, as well as the primary feathers, are displayed in a
manner quite peculiar to this one species during the act
of courtship, and at no other time, were given to him as
an ornament. If so, he must likewise admit that the fe-
male was created and endowed with the capacity of ap-
preciating such ornaments. I differ only in the convic-
tion that the male Argus pheasant acquired his beauty
gradually, through the females having preferred during
many generations the more highly-ornamented males ; the
aesthetic capacity of the females having been advanced
through exercise or habit in the same manner as our own
taste is gradually improved. In the male, through the
fortunate chance of a few feathers not having been modi-
lied, we can distinctly see how simple spots with a little
fulvous shading on one side might have been developed
by small and graduated steps into the wonderful ball-and-
socket ornaments ; and it is probable that they were actu-
ally thus developed?

Every one who admits the principle of evolution, and
yet feels great difficulty in admitting thai, female mam-

384

GENERAL SUMMARY

[Part II.

mals, birds, reptiles, and fish, could have acquired the
high standard of taste which is implied by the beauty of
the males, and which generally coincides with our own
standard, should reflect that in each member of the verte-
brate series the nerve-cells of the brain are the direct off-
shoots of those possessed by the common progenitor of
the whole group. It thus becomes intelligible that the
brain and mental faculties should be capable under similar
conditions of nearly the same course of development, and
consequently of performing nearly the same functions.

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 ar-
rived are supported by sufficient evidence. If he accepts
these conclusions, he may, I think, safely extend them to
mankind ; but it would be superfluous here to repeat what
I have so lately said on the manner in which sexual selec-
tion has apparently acted on both the male and female
side, causing the two sexes of man 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 low-
ly-organized progenitors.

He who admits the principle of sexual selection will
be led to the remarkable conclusion that the cerebral sys-
tem not only regulates most of the existing functions of
the body, but has indirectly influenced the progressive de-
velopment of various bodily structures and of certain men-
tal qualities. Courage, pugnacity, perseverance, strength
and size of body, weapons of all kinds, musical organs,
both vocal and instrumental, bright colors, stripes and
marks, and ornamental appendages, have all been indi-
rectly gained by the one sex or the other, through the
influence of love and jealousy, through the appreciation
of the beautiful in sound, color, or form, and through the
exertion of a choice ; and these powers of the mind mani-

Chap. XXI.] AND CONCLUDING REMARKS. 385

festly depend on the development of the cerebral sys-
tem.

Alan scans with scrupulous care the character and pedi-
gree 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. lie is impelled by nearly
the same motives as are the lower animals when left to
their own free choice, though he is in so far superior to
them that he highly values mental charms and virtues.
On the other hand, he is strongly attracted by mere wealth
or rank. Yet he might by selection do something not
only for the bodily constitution and frame of his offspring,
but for their intellectual and moral qualities. Both sexes
ought to refrain from marriage if in any marked degree
inferior in body or mind ; but such hopes are Utopian and
will never be even partially realized until the laws of in-
heritance are thoroughly known. All do good service
who aid toward this end. When the principles of breed-
ing and of inheritance are better understood, we shall not
hear ignorant members of our legislature rejecting with
scorn a plan for ascertaining by an easy method whether
or not consanguineous marriages arc 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 pov-
erty is not only a great evil, hut tends to its own increase
by leading to recklessness in marriage. On tin' other
hand, as Mr. Galton has remarked, if the prudent avoid
marriage, while the reckless marry, the inferior members

will tend to supplant the better members of society;
Man, like eyery other animal,* has no doubt adranced to
his present, high condil ion t h rough a si niggle lor existence
consequent on his rapid multiplication; and if he li to
advance still higher he must remain Bubjecl to a lerere

(iKNKKAIi sTMMAUY

[Taut II.

struggle. Otherwise he would soon sink into indolence,
and the more highly-gifted men would not be more suc-
eessful in t lie 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 cus-
i(»ms from succeeding best and rearing the largest number
of offspring. Important as the struggle for existence has
been and even still is, yet as far as the highest part of
man's nature is concerned there are other agencies more
important. For the moral qualities are advanced, either
directly or indirectly, much more through the effects of
habit, the reasoning powers, instruction, religion, etc., than
through natural selection ; though to this latter agency
the social instincts, which afforded the basis for the devel-
opment of the moral sense, may be safely attributed.

The main conclusion arrived at in this work, namely,
that man is descended from some lowly-organized form,
will, I regret to think, be highly distasteful to many per-
sons. But there can hardly be a doubt that we are de-
scended from barbarians. The astonishment which I felt
on first seeing a party of Fuegians on a wild and broken
shore will never be forgotten by me, for the reflection at
once rushed into my mind — such were our ancestors.
•These men were absolutely naked and bedaubed with
paint, their long hair was tangled, their mouths frothed
with excitement, and their expression was wild, startled,
and distrustful. They possessed hardly any arts, and, like
wild animals, lived on what they could catch ; they had no
government, and were merciless to every one not of their
own small tribe. He who has seen a savage in his native
land will not feel much shame, if forced to acknowledge
that the blood of some more humble creature flows in his

Chap. XXI.]

AND CONCLUDING REMARKS.

387

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 tor-
lure his enemies, offers up bloody sacrifices, practises in-
fanticide without remorse, treats his wives like slaves,
knows no decency, and is haunted by the grossest super-
stitions.

Man may be excused for feeling some pride at having
risen, though not through his own exertions, to the very
summit of the organic scale : and the fact of his having
thus risen, instead of having been aboriginally placed
there, may give him hopes 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 allows
us to discover it. I have given the evidence to the best
of my ability ; and we must acknowledge, as it seems to
me, that man with all his noble qualities, with sympathy
which feels for tlie most debased, with benevolence which
extends not only to other men but to the humblest living
creature, with his godlike intellect which has penetrated
into the movements and constitution of the solar system
— with all these, exalted powers — Man still hears in his
bodily frame the indelible stamp of his lowly origin*

INDEX.

A.

Abbott, C, on tho battles of seals, ii. 229.
Abductor of tho fifth metatarsal, presence

of, in man, i. 128.
Abercrombir, Drn on disease of the brain

affecting speech, L 56.
Abiponrs, marriage -customs of the, 11. 856.
Aiiui -SiMiiF.u caves of. i. '-'n'.l.
Abortion, prevalenco of the practice of, i.

129.

Abstraction, 1. 60.

AcalU*, stridulation of, i. 872.

Ac4intho(i(ivtylu& ctipeiutU, sexual differ-
ences of color in, IL 84.

Accentor modularin, ii. 189.

Acclimatization*, difference of, in diffcr-
ent races of men, i. 209.

Acfistida, stridulation of the, 1. 841, 842,
84s ; rudimentary Btridulating organs in
female, i. 848.

Aciliu* eulcatus, elytra of tho female, L
S88.

Acont ha. development of spurs in tho fe-
male of, ii. 154.

AorifliiitiF. stridulation of the. I. 812. 3i.">;
rudimentary Btridulating organs in fe-
rn .1-. i. U<

Acting, i. 224.

A< tiniiry bru'ht colors of. i. Ml 8.

Admiral butterfly, L 880.

Adoption of the young of other animals
by female monkeys, L 89.

Advancement in the organic, scale. Von
liaers definition of. i.

Abbt, on the difference between the skulls
of man and the quadrumana, L 1 88.

^Estiiktio faculty, not highly developed In
savages, i. 62.

Apfrction, maternal, L 89 ; manifestation
of, by animals, L 89 ; parental and filial,
partly the result of natural selection. L
77 ; shown by birds in confinement, for
certain iktsous, ii. 105; mutual, of birds,
ii. 104.

Africa, probably the birthplace of man. 1.
191 ; South, crossed population of, L 217,

South, retention of color by tho Dutch
in,1. 288 ; South, proj>ortlon of the sexes
la the butterflies of, I. 801; tattooing
practised in, 11. 828 ; Northern, coiffure
of natives of, ii. 824.

Aoabsiz, I*, on conscience in dogs, i. 75 ;
on the coincidence of the races, of man
with zoological provinces, L 210; on the
number of species of man, 1. 218; on the
courtship or the land-snails, L 815; on
the brightness of the colors of male fishes
during the breeding-season, ii. 12 ; on the
frontal protuberance of the males, of
Geophagii* and ( 'ichUi. ii. 18, 26 ; on the
Blight sexual differences of the South
Americans, ii. 80s; on the tattooing of
the Amazonian Indians, ii. 826.

Agr, In relation to the transmission of
characters in birds, ii. 175; variation in
accordance with, in birds, IL 208.

Agelam Pheendceu*, ii. 111.

Ageronia feronia, noise produced by, 1.
875.

Agriotu dimorphism in, 1. 852.
Agrion RamburiL, sexes of, i. 851.
AoRioNiDiE, difference in the sexes of, L
861.

Agrotis earclamationU, I. 859.

Ac; 1 k. tertian, doir suffering from, 1. 12.

Alt/turn* jioh/tni a*, voting of IL, 211. .

Aionoh, hairiness of the, Ii. H06.

A /at tonhi, younj.' of, ii. 20S. %

Ale** palmetto, ii. 247.

Ai.drr and Hancock. MM, on the nudi-

branch molluscs, L 817.
A lorn, Mr- on the stridulation of ScohjttuL

L 868.

Allkn, J. A., on the relative size of tho
seves of < 'ullnrhinu* urninuM, ii. IMS;
on the mane of OUtria )uhatay 11. 255 :
on the pairing of seals, IL 257 ; on sexual
differences in the color of bate, ii. 278.

Allen, 8, on the habits of J/oploptenu,
ii. 46; on the plumes of herons, 11. 79;
on the vernal moult of flerodias, bubiU-
ctM, ii. 80.

Alligator, courtship of the male, I. 264,
iL 27 ; roaring of the male, L 822.

INDEX.

389

Amadavat, pugnacity of male, ii. 46.

Amadina Lathami, display of plumage
by the male, ii. 91.

Amadina castanotis, display of plumage
by the male, ii. 91.

Amazons, butterflies of the, i. 301; fishes
of the, ii. 17.

America, variation in the skulls of abori-
gines of, i. 104 ; w ide range of aborigines
of, i. 211; lice of the natives of, i. 212;
general beardlessness of the natives of,
ii. 307.

America, North, butterflies of. i. 301 ; In-
dians of, women a cause of strife among
the, ii. 308 ; Indians of, their notions of
femate beauty, ii. 327, 328.

America, South, character of the natives
of, i. 208 ; population of parts of, i. 216 ;
piles of stones in, i. 224 ; extinction of
the fossil horse of, i. 231 ; desert-buds of,
ii. 214; slight sexual difference of the
aborigines of, ii. 367 ; prevalence of infan-
ticide in, ii. 347.

American languages, often highly artifi-
cial, i. 108.

Americans, wide geographical range of, i.

108 ; and negroes, difference of, i. 238 ;

aversion of, to hair on the face, ii. 219 ;

native, variability of, i. 210.
Ammophila, on the jaws of, i. 232.
Ammotraffm trayelaphm, hairy forelegs

of, ii. 269, 272.
Amphibia, affinity of, to the ganoid fishes,

L 196; vocal organs of the, ii. 315.
Amphibians, i. 2ol, ii. 22; breeding while

immature, ii. 206.
Ant/thioxtM, i. 196.

Ami'iiii'oda, males sexually mature while

young, ii. 205.
A mi soph HI., negro character of features

of, i. 210.
Asal appendages of insects. I. 332.
Analogous variation in the plumage of

birds, ii. 71.
AmtH, ii. 172.

AiuiH acuta, male plumage of, il. 81,
Aiian botoliOA, mule plumage of, ii. Hi.
A tUU hi*tri<n,ic,t, ii. 200.
A luiMtomuM oHi'itann, sexes and young <>f,

H. 20b; white nuptial plumage of, ii.

218.

Anatio.k, voices of, Ii, 57.

Anaw j u III UK, difference ill the Sr\eS of I.

ML

An<;i.oHa\onh, estimation of the board

among the, n. 888.
Animw.h. cruelty of eavagon t<>, 1.01; do
mestlttted, more fertile tban wild,!. 127;
oharaetarl common to man ami. i 17B;
domestic, change of bn ode of, 11, W8.

Asm i. ii. a, I. Ills.
Asm i.usa, I. :t I s.

AnoUt OPUtaMlut, male ere I of, il B0;
pugnndty of the mulu, IL B0; throat

poueh „i II. 81.

JLnoblum tfnatllatuin, loiinda prod I

by, i. MS,

An*<<r ( W/o/'/< ttlUi II. 1 18,

Anser cygnoides, ii. 110 ; knob at the base
of the beak of, ii. 124.

Anser hyperboreus, whiteness of, ii. 218.

Antelope, prong-horned, horns of, i. 279.

Antelopes, generally polygamous, i. 25S ;
horns of, i. 279, ii. 234 ; canine teeth of
some male, ii. 230 ; use of horns of, ii.
259 ; dorsal crests in, ii. 268 ; dewlaps of,
ii. 270; winter change of two species of,
ii. 284 ; peculiar markings of ii. 285,

Antenna, furnished with cushions in the
male of Pentke, i. 333.

Anthidium municatum, large male of, i.
337.

Antlwcharix cardamine-% i. 376, 3S1 ; sax-
ual difference of color in, i. 396.

Anthocharis gemttia, i. 381.

AntlvocharU sara, i. 881.

Antlwphora acerzorum, large male of, i.
337.

Anthophora retma, difference of the sexes

in, i. 354.
Anthm, moulting of, ii. 79.
Antiiropid^e, i. 187.

Antigua, Dr. Nicholson's observations on

yellow fever in. i. 236.
Antics of birds, ii. 65.
Antilocapra Americana, horns of, i, 280,

ii. 234.

Antilope bezoartica, horned females of, ii.
235, 237 ; sexual difference in the color
of, ii. 274.

And/ope Dorcas and euchore, ii. 234.
Antilope euchore, horns of, ii. 239.
Antilope montana, rudimentary canines

in the young male of. ii. 246.
Antilope viger, King-si ng, caama, and

gorgon, sexual differences in the colors

of. ii. 275.
A nt Hope ore<tx, horns of, 1. 279.
Antilope taiga, polygamous habits of, i.

258.

Antilope xtrepsiceros, horns of. i. 279.

Antilope Kiiliguttitrosd, absence of sub-
orbital pits in. ii. 86T.

Antipathy, shown by birds in confine-
ment, to certain persons, ii. 106.

Ants, i. 179; playing together, L 88; mem-
ory in, I. It ; intercommunication of, by
means of the antenna1, I. 56 ; larire si/.o

of the oarebra] nngtLi in. i. i M) ; eoldlMs

large jaw s of. i. I t'.t ; difference of the
sexes in, I. UM; recognition of each other

by, after separation, i B54.

As is. While, habits of, i. liMt.
Am ha, II. U,

Ajnitanin wulisbri*, male unknown, I.
306.

Apathm, difference of the sexes In, I :t.W
Apatuni /W\ I. BT4, ST*.

An ., anthropomorphous, I. is'.»; diiv.r-

enro o|' the \ounif, from the adult, I. |M ;

building plntAirma, I. M ; probable
*p ly extermination of the, i IN; <-i .

tlolctol.lhe evolution of, L 88t| ".ml

artel attitude ..r aomo. I. 181 ; maatoM

proccs.H ot, I 137; llllliielice of the Juw-

lllllhcleit ..II the ph\ -loell \ ot I I I'..

390

INDEX.

female, destitute of large canines, L 150;
Imitative faculties of, i. 155 ; canine teetii
or male, iL 230; females of some, less
hairy beneath than the males, H. 861.

Aprs, long-anned, their mode of progres-
sion, L 187.

Apis mtUjflca, largo male of, i. 887.

Apollo, Greek statues of, 1L 888.

Apoplexy in Cebns Aearcr, i. 12.

Approbation, influence of the lore of, i.
82, 88, 157, 153.

Appendages, anal, of Insects, 1. 832.
prosmietiis ecapufatuM, ii. 106.

Aquatic birds, frequency of white plu-
mage in, U. 219.

Ai/uita cJirysaetos, U. 100.

Arab women, elaborate and peculiar coif-
fure of, ii. 886.

Arabs, gashing of cheeks and temples
among the, IL 828.

Araciinida, 1. 821.

Araktian, artificial widening of the fore-
head by the natives of, ii. 885.

Arftoricola, young of, ii. 162.

An In tipt, n/.r. i. 1 !»('».

Arctiid-e, coloration of the, i. 8S8.

Ardea ' asha, rufeecene, and carulea,
change of color in, ii. 221, 222.

Ardea carulea, breeding in immature
plumage, ii. 205.

Anhu gularis. change of plumage in, ii.
222.

Anfeti Aerodias, love-gestures of the male,
11.65.

Ardea ludoriciana, age of mature plu-
mage in, ii. 204 ; continued growth of
crest and plumes in the male of, ii. 207.

Ardea nycticorav, cries of, ii. 48.

Arileohil young of. ii. 1XJ.

Ardetta, changes of plumage In, ii. 170.

Argentxotl, L 28.

Abovb pheasant, IL 69, 98, 178; display of
plumage by the male, IL 89; ocellated
spots of the, ii. 128, 135; gradation of
characters in the, IL 185.

Argyll, Duke of, the fashioning of Imple-
ments peculiar to man, 1. 50; on the con-
test in man between right and wrong, L
100; on the physical weakness of man, L
149 ; on the primitive civilization of man,
L 174 ; on the plumage of the male Argus
pheasant, 11.89; on VrostMe Benjamini^
fa. 145; on the nests of birds, ii. 159; on
variety as an object in nature. IL 220.

Argynni* aghiia, coloring of the lower
surface ot, L 884.

Arimri* sexual differences In the

wings of 1. 885.

Aristocracy, Increased beauty of the, il.
840.

\ i: m a, proportions of, in soldiers and sailors,
1. 112 ; direction of the hair on the, L
135.

Arms and hands, free use of. indirectly cor-
related with diminution of canines, i. 188.

Aeekht of development, L 117.

Aaaow-nr.ADS, stone, general resemblance
of, L 224.

Arrows, use of. 1. 224.
Arteries, variations in the course of the,
L 104.

Artery, effect of tying, upon the lateral

channels, 1. 112.
Artiiropoda, i. 818.
Arts practised l>y savages, i. 2'2.r>.
Ascension, colored incrustation on the

rocks of, I. 817.
Ascidia. allinlty of the lancelet to, i. 196;

tadpole-like larva? of, i. 197.
Ascimans, L 815 ; bright colors of some, I.

813.

Asinits, Asiatic and African species of. ii.

291.

Aniiuut heniopu*. il. 291.

Ass, color- variation s of the, ii. 291.

Atele*\ effects of brandy on an, L 12 ; ab-
sence of the thumb in, I. 185.

Atelee beelaebutK, ears of, L 22.

Atelea marginatum, color of the ruff of. ii.
278; hair on the head of, li. 105; on the
recognition of a dog by a turkey, 11. 106 ;
on the selection of a mate by female
birds, 11. 199.

Ateuchu*, stridulatlon of, L 372.

Ati u<-Aim cicnti icoMiut, habits <>f. i. 865.

AtAalia, proportions of the sexes in, L 805.

Attention, manifestations of, in animals, i.
48.

Aitdootn, V., on a hymenopterous parasito
with a sedentary male, i. 264.

ArornoN, J. .J., on the pugnacity of male
birds, ii. 41, 46; on Trtrao eupido, 11.
47; on Ardea nycHeoram, IL 48; on
SturneUa ludovicuina, li. 48 ; on tho
vocal organs of Tftrao cupido. IL 58; on
the drumming of tho male Tetrao vtn-
beJlus, 11. 69 ; on sounds produced by tho
nightjar, li. 61 ; on Ardea Aerodias and
Cathartee jota, U. 65; on the spring
chance of color in some finches, IL 83 ;
on Minnie polygf otitis, li. 112; on the
turkey, IL 114, 116; on variation in tho
male scarlet tanager, ii. 121 ; on the hab-
its of Pyranga awtira, il. 159; on local
differences in the nests of the same spe-
cies of birds, IL 163; on the habits of
woodpeckers, 11. 167; on BombyeUla
Carolineneie, IL 172 ; on young females
of Tanagra astira acquiring male
characters, ii. 172; on the immature plu-
mage of thrushes, IL 177 ; on the Imma-
ture plumage of birds, IL 178, et eeq. ; on
birds breeding in immature plumage, IL
205; on the growth of the crest and
plumes in the male Ardea ludovidama,
fa. 206; on the change of color in some
species of Ardea, IL 221 ; on the i specu-
lum of Mergus rucuUatue, iL 27 1 ; on
the musk-rat. ii. '.'■-».

ArnruoN and Iiachman, MM, on squirrels
fighting, IL 228; on the Canadian lynx, iL
255.

Ai'sten, N. I~, on Anolie eriUateUus, IL

81.

Australia, half-castes killed by the na-
tives of; L 212; lice of the natives of; L

INDEX.

391

212 ; not the birthplace of man, i. 191 ;
prevalence of female infanticide in, ii.

Australia, South, variation in the skulls

of aborigines of, i. 104.
Australians, color of new-horn children

of, ii. 303; relative height of the sexes

of; ii. 305 ; women a cause of war among

the, ii. 308.

Axis deer, sexual difference in the color

of the, ii. 276.
Aymakas, measurements of the, i. 115 ; no

gray hair among the, ii. 304 ; hairlessness

of the lace in the, ii. 307 ; long hair of the,

ii. 331.

Azaea, on the proportion of men and
women among the Guaranys, i. 302 ; on
Palamedea comuta, ii. 44; on the
beards of the Guaranys, ii. 307 ; on strife
for women among the Guanas, ii. 309 ;
on infanticide, ii. 328, 347 ; on the eradi-
cation of the eyebrows and eyelashes by
the Indians of Paraguay, ii. 332; on poly-
andry among the Guanas, ii. 349; celi-
bacy unknown among the savages of
South America, ii. 350 ; on the freedom
of divorce among the Chai-ruas, ii. 356.

Babbage, C, on the greater proportion of
illegitimate female births, i. 292.

Babieusa, tusks of the, ii. 252.

Baboon, employing a mat for shelter
against the sun, i. 51 ; manifestation of
memory by a, i. 43; protected from pun-
ishment by its companions, i. 74; rage
excited in, by reading, i. 41.

Baboon, Cape, mane of the male, ii. 255;
Ilamadryas, mane of the male. ii. 255.

Baboons, effects of intoxicating liquors on,
i. 12; ears of, i. 22; manifestation of ma-
ternal affection by, i. 88; using stones
and sticks as weapons, i. 50; cooperation
of, i. 72; silence of, on plundering expe-
ditions, 1. 75; diversity of the mental
faculties in, i. 106; hand's of. i. 184: hab-
its of, i. 1:56; variability of the full in. i.
144; uppannt polygamy of, i. 266; po-
lygamous and social habits of, 11.846, 846.

Baciiman, Dr., on the fertility of mulat-
to.*, 1. '218.

Baku, K. K., von, on embryonic develop-
ment, i. I I.

BaMUOT, \V., on the social virtues among
primitive men, I. Ml; on the value of

obsdlenoa I. IN: on human progress, i.
110: on the persistence of savage tribes

In classical times, I. TM.

U ah. i.v, B. M., on the fighting of stags, ii.

041 : on the I I.- of lighting of the Ital

Ian buffalo, II. 989,
B ms. A., on the hense of duty, I. 6s ; aid

springing from sympathy, 1. 74; on Lbs
bases of sympathy, 1. 78 ; on love of ap
probation, etc., i. 82 ; on the Idea ol boau
ty, II. 887.

Bated, W., on a difference in color between
the males and females of some Entozoa,
i. 312.

Bakee, Mr., observation on the proportion
of the sexes in pheasant-chicks, i. 297.

Bakee, Sir S., on the fondness of the Arabs
for discordant music, ii. 64; on sexual
difference in the colors of an antelope, ii.
275 ; on the elephant and rhinoceros at-
tacking white or gray horses, ii. 281 ; on
the disfigurements practised by the ne-
groes, ii. 282; on the gashing of the
cheeks and temples practised in Arab
countries, ii. 323 ; on the coiffure of the
North Africans, ii. 324 ; on the perfora-
of the lower lip by the women of La-
tooka, ii. 325 ; on the distinctive charac-
ters of the coiffure of central African
tribes, ii. 326; on the coiffure of Arab
women, ii. 336.

"Balz" of the Black-cock, ii. 43, 96.

Bantam, Sebright, i. 250. 285.

Banteng, horns of, ii. 236; sexual differ-
ences in the colors of the, ii. 275.

Banyai, color of the, ii. 330.

Babbaeism, primitive, of civilized nations,

i. 174.

Baebr, filamentous, of the feathers, in cer-
tain birds, ii. 70.
Baer, Mr., on sexual preference in dogs, ii.
. 259.

Barbington, Paines, on the language of
birds, i. 53; on the clucking of the hen,

ii. 49; on the object of the song of birds,
ii. 50 ; on the singing of female birds, ii.
51 ; on birds acquiring the songs of other
birds, ii. 52 ; on the muscles of the lar-
ynx in song-birds, ii. 53; on the want of
the power of song by female birds, ii.
156.

Bareow, on the widow-bird, 11. 98.

Baeti.ktt, A. D., on the tragopan, 1. 261 ;
on the development of the spurs, in
CroHHopiilon auritum, i. 2S0; on the
fighting of the males of pUtWOJpUtua
ymiihenxix, ii. 44 ; on the knot, ii. 7^;
on display in male birds, ii. SS; on the
display of plumage by the male /'<>/>/-
jiltrt rot), ii. sr>; on ("iotn)o/>ti!i>n auri-
tnin and /'/uittitiiiuH Wall hit ii, ii. s'.l ;
on the habits of /.o/ihop/ioriiM, il. 116;
on the color of the mouth in /litems
l/icomiH, ii. 123; on th.- Incubation <>f
the inssiHwy, i'- L95 ; on the ( ape Buf-
falo, ii. '239; on the use of the horns of
antelop. •«., ii, MOj on UC lighting of male
wnrt-hoe>, ii. '254; on Amiuofrtn/ii* tin
g,laj>futK, II. 269; on the color* of <Vr-
vofHthrciiH vf/i/itiH, II. '277; on the colors
of the faces of monk, v *, ii. '295 ; on the
naked surfaces of monkeys, II. 860,

Baicikam, on the courtship of th.' Ilia!,'

alligator, 11. 87.
lUsgl K. language, highly artificial. I. 59.
Hatk, < "ii the superior activity of

male crustaccn, I. 268; on the propoi

Hons of the se\es In . rid is, I :tn7 j mi th..

cliche of crustae. a, I. .'I'.'O; on the relatlv n

INDEX.

size of the sexes In crustacea, L 323; on
the colors of crustacea. i. 326.

Bates, H. W„ on variation In the form of
the head of Amazonian Indians, L 107;
on the proportion of the Rexes among
Amazonian butterflies, i. 801 ; on sexual
differences in tin w:ngs of biittcrllics. i.
885: on the field-cricket, t. 842; on Pu-
rode* tmMttrrimu*, 1. 8.56; on the
horns of Ijmiellicorn beetles, 1. 359, 360;
on the colors of Epicalioi, etc-, L 876;
on the coloration of tropical butterflies, 1.
879 ; on the variability of PapUio .Ssmm-
tri* and <'hil<lrentr, '\.:V.M\ on male and
female butterflies Inhabiting different sta-
tions, i. 890; on mimiekry, i. 898; on the
caterpillar of a Sphinx, i. 402 ; on the
vocal organs of the umbrclla-bird, ii. 56;
on the toucans, ii. 217; on JiravhyuruH
tuilritH, ii. •_>-.>:>.

Batokas, knocking out two upper inci-
sors, ii. 824.

Batraciiia, ii. 24; eagerness of male, L
268.

Bats, sexual differences in the color of, ii.
272.

Battle, law of, i. 175; among beetles, L
:!<«:{; among birds. II. 8> ; among mam-
mals, 1L 229, et teq. ; in man, 11. 808.

Beak, sexual difference in the forms of
the, 11. 87 ; In the color of the, ii. 69.

Beaks, of birds, bright colors of, ii. 217.

Bkaed, development of, in man, iL 802 ;
analogy of tin-, in man and the ijuadrti-
mana, ii. 304; variation of the develop-
ment of the. in dilfcnnt nices of men. ii.
:?ot; ; estimation of. amontr Uanlcd na-
tions, ii. 888 ; probable origin of the, iL 856.

Beards, in monkeys, L 184 ; of mammals,
ii. •.'••,:».

BxAcnrtrL, taste for the. in birds, IL 108 ;
in the (juodrumano, ii. 2*»2.

Beauty, sense of, in animals, L 61 ; appre-
ciation of, by birds, IL 107; influence of,
ii. M22. :<--'T ; variabilitv of the standanl
of,iL358.

Beavan. Lieut, on the development of the

horns In Certms Etdi, L 279.
Bk. wi-.it, instinct and Intelligence of the,

L 86, 87; voice of the, iL 264 ; castoreum

of the, ii. 266.

IlKU KIls, Uittic* of male, ii. 223.

Bevhbtein, on female birds choosing the
best singers among the males. 11. 49 : on

on pairing the canarv and siskin, ii. I Hi;

on a subvarietv of the monk pigeon, U.

126; on spurred bens, IL 154.
Beodoc, l>r„ on causes of difference in

stature, L 111.
Bee-katee. iL 53.

Bees, L 70; destruction of drones and
queens by, L 77; poOen-haakrta and
stings of, 1. 149 ; female, secondary sexu-
al characters of, I. 246 ; diffcrerce of the
eexca In, L 854.

Beetle, luminous larva of o, I. 885,
Un ii is. i.."..Vi; si/.e of the rerebral gan-
glia in, i. 140; dilatation of the fore tarsi
in male. i. 888; blind. L 856; striduiatiou

of, L 866.

Belgium, ancient inhnhiuint* of, I. 228.
Bell, Sir C, on emotional muscles in man,

1.5; "snarling muscles,"!. 122; on the

hand. i. 136.
BELL, T., on the numerical porportion of

the sexes in moles, 1. 296; on the newts,

ii. 23; on the croaking of the frog, ii.

•_'.*»: on the difference in the coloration

of the sexes in '/.,>,,i,» ■< ririjHiru, iL 85;

on moles fighting. 11. 228.
Bell-iubd, sexual difference In the color

of the, 11. 75.
Hell-hirds. colors of II. 218.
Benevolence, manifested bv binls, ii

104.

Bennett, A. W- on the habits of Z>rtwi/*-

iim irrunifiiM, ii. |".»6.
Bennett, Dr„ on binls of paradise, ii. 85.
fSerm'rfu tintarctU'it, colon* of, ii. 218.
Hkkmi I K gander pairing with a Canada

goose, ii. lny.
Bettonl, E., on local di (Terences In tho

nests of Italian birds, il. 168.
ItiioTK.As. color of the U-anl In, ii. 804.
lili i in,;, i. disciform tall-feathers of ii. M».
JKMo, sexual difl'crenccs in Uie genus, L

33s.

Bicbat, on beauty, 11. 888.

Bile, colored, in many animals, 1. 814.

Bui aha, L 188.

l»n:i>s, imitations of the songs <>f other
birds by, i. 42; dn-aming, i. 44; lau-
gnage of. i. 53; » use of U-aiity in. i. 61;
pleasure of, in inciiUition, 1. 76; male,
incubation by, L 208: and reptiles, alli-
ance of. L 204; sexual dUfcieuoss la the

beak of some, L 247 ; migratory, arrival
of the male before the female. L 251 ; ap-
pan-nt rt>lation between [<olygamy and
marked sexual differences ' in, L 261;
monogamous, becoming polygamous un-
der dum.-tieatinn. i. J'.J : eagerness c.f

male In pursuit of the female, L 968;
wild, numerical proportion of the sexes
in, L 297; secondary sexual characters
of, Ii. 86; difference of size in the sexes
of. IL 41 ; fights of male, witnessed by fe-
males. iL 46; dlsplav of male, to capti-

vate the females, ii." -47 ; close attention
of, to the songs of others, IL 00; aoqulr-
ing the song of their foster-parents. II.
52; brilliant, rarely good songsters. 11. 58;
love-antirs and dances of, II. 65; colora-
tion of, iL 7L, ft «m. ; moulting of IL
77, et a*W.,* unpaired, II. 99; male, sing-
ing out of season. IL 102; mutual amo-
tion of, IL 104; In confinement, distin-
guish persona, iL 105; hybrid, pnxlue-
tion of, iL 109; Knmpenn. number of
species oC IL 119; variability of, iL 119;
gradation of secondary sexual characters

in, IL 129; obscurely colored, building
concealed nests, IL 161; young femal*

INDEX.

393

acquiring male characters, ii. 172 ; breed-
ing in immature plumage, ii. 205 ; moult-
ing of; ii. 204; aquatic, frequency of
white plumage in, ii. 219 ; vocal court-
ship of, ii. 315; naked skin of the head
and neck in, ii. 377.

Birgua lalro, habits of, i. 325.

Birkbeck, Mr., on the finding of new
mates by Golden Eagles, ii. 100.

Birthplace of man, L 191.

Births, numerical proportions of the sexes
in, in animals ana man, i. 255, 25G ; male
and female, numerical proportion of, in
England, i. 291.

Bischoff, Prof., on the agreement be-
tween the brains of man and of the
Orang, i. 10; figure of the embryo of the
dog, i. 15; on the convolutions of the
brain in the human foetus, i. 16; on the
difference between the skulls of man and
the quadrumana, i. 183.

Bishop, J., on the vocal organs of frogs, ii.
26; on the vocal organs of corvine bird?,
ii. 52 ; on the trachea of the Merganser,
ii. 57.

Bison, American mane of the male, ii. 255.
Bitterns, dwarf, coloration of the sexes of,
ii. 170.

Biziura lohata, musky odor of the male,

ii. 36; large size of male, ii. 41.
B! a< kisiri>, sexual differences in the, i.

260; proportion of the sexes in the. i.

296; acquisition of a song by a, ii. 52;

color of the lieak in the sexes of the. ii.

69. 817; pairing with a thrush, ii. 109;
colors and nidilication of the, ii. 162;
young of the. ii. 210; sexual difference

in coloration of the, ii. '.'16.

Black-buck, Indian, sexual difference in
the color of the. ii. 275.

Blackcap, arrival of the male, before the
f. inale. i. 251 ; young of the. ii. 21 0.

Bi. w k-c KM k, polygamous, i. 261 ; propor-
tion of the sexes in the, I. 297 ; pugnacity
and love-dance of the, ii. 42 ; call of the,
ii. 08; moulting of the, il. 79; duration
of the courtship of the, IL 96; sexual
difference in coloration of the. Ii. 210;
crimson eye -cere of the, il. 217; ami
pheasant, hybrids of, il. 109.

Bl M k QIOCUL characters of voting, ii.
177, 1HIJ.

BlackwaI.L, J., on the speaking of tho
magpie, I. 57; on tin- desertion of their
young by ■Wallows, 1. SO ; on the supe-
rior activity of mull- spiders, 1. 263; on
the proportion of the soxos In spiders, I.
808; on mum] variation of color in spi-
ders, I. 89Tj "i» mals ipldi ra, I. 888,

III. MM. I ll >ohK S. al. hood of the. II. 'il'-',.

Hi. aim:, on the affections of do,.-*, n 2ft
Hi. \iu. Dr. on the 1 1 lativfl liability u| I n

ropoani to yellow ft nor. I. 284,
Blaksj, 0, 0- on Uie Jaw frutn l-i Naulctte,

I. Hi.

BLAXiaTOW, Cap! on tie' Vmortoan snip*
II I'd ; on id,, duin. % of Ttti;m i>h,i»i,i
mil it*, II 06.

Blasitjs. Dr., on the species of European

birds, ii. 119.
Bledim taurm, hornlike processes of male,

i. 363.

Bleeding, tendency to profuse, i. 2S3.
Blenkirox, Mr., on sexual preference in

horses, ii. 260.
Blexnies, crest developed on the head of

male during the breeding-season, ii. 12.
BUdhiaa mult! punctata, stridulation of, i.

368.

Bloch, on the proportions of the sexes in

Fishes, i. 298.
Blood, arterial, red color of. i. 314.
Blood-pheasant, number of spurs in, ii.

43.

Bluebreast, red-throated, sexual differ-
ences of the, ii. 187.

Bllmenbach, on Man, i. 107; on the largo
6ize of the nasal cavities in American
aborigines, i. 114; on the position of man,
i. 182; on the number of species of man,
i. 218.

Blyth, E., observations on Indian crows,
i. 74; on the structure of the hand in
species of Hylobate*, i. 135; on the as-
certainment of the sex of nestling bull-
finches by pulling out breast-feathers, ii.
23 ; on the pugnacity of the males of
Gallinula crmtata. ii. 39 ; on tho pres-
ence of spurs in tho female AtpwNSO*
tnuH triithv(>i>hth(tlniH.\ ii. 41: on tho
pugnacity of the amadavat, ii. 47; on tho
spoonbill ii. 57; on the moulting of An-
tlni.s. ii. Ill ; on the moulting of bustards,
plovers, and Call ha hnnkira. ii. s«>; oil
tho Indian honey-buzzard, ii. 121; on
sexual differences" in the color or the eyes
of hornbills, ii. 123; on Oriolu* meUino-
cijihuhiH. ii. 17o; on I'ahvornix Jiintni-
cum. ii. 171; on the genus Anht/a, il.
171; on the peregrine falcon, ii. 171; on
young female birds acquiring male char-
acters, ii. 172; on the immature plu-
mage of birds, ii. 177; ,,n representative
siie. ies of birds, ii. lsj; on the young of
Tiii iii.i; ii. 188; on anomalous young of
l.iiniuH rtiftitt and i'ohjiiihim glaciali*,
il. 202; on tin- neves ami young of tho
sparrow ii jo i ; on dimorphism In somo
herons, ii. 20.".; on orioles breeding in
Immature plumage. II. 205; on the \e*
and young of Jlu/i/um and Aluminum*,
Ii. 2os; on the young of the blackcap
and blackbird. II.' 210; on the voting of
the Monechat, II. 211 ; on the white plu-
mage thf jlnflifrrTTifi, II. 219; on the horna

of Anti/i,ii,< l„ ;<>,t, t,,;i. II. 2 1.'.; on the
horns of lto\liio union'-, ii 2H'.; on ti,..
BMd« of fighting or Orl* c</.7.v./.M, II.
23S; on the \oliv of the tJlbl s, II 26. 1;

on tho crest of th« mala wild mi, li.

26s; oil tho color* of /'iirfiM />»'<•/. I, H.
274; on llm colors of Antiloi* l***ir-
U,hi, II. 275; on the d«w,dopmonl of ih«
bona in the k.k^i.n. mi, i i i.n i isjii

|..p. s l 2. ' ..Mil, . ..: ,i ,.i in. \m«
-b i, il on *e\u il dub i. n t color

394

INDKX.

In ITi/lobatt* hoofocl; II. 277; on the
hog-deer, ii. 2*0 ; on the l>eard and whis-
kers Id the monkey becoming white
witj age, 1L 804.
Boar, wild, polygamous In India, 1.259;
we of the tusks by the. ii. 245; lighting
ot 1L 251.

Hon utn and Corl.it'>, MM., on tho trans-
mission of sexual peculiarities in pigeons,
i. 274; on the antipathy shown by some
female pigeons to certain mules, ii! 11 ».

Bold, Mr_ on the singing of a sterile hy-
brid canary, iL 50.

Bomhet, on the variability of the standard
of l>caiitv in Kurope, 11. 854.

Bombug, difference of the sexes in, i. 855.

Bombtcida. coloration ot L 3?2: pairing
of the, L 888.

]li nn), i/cilhi < ,iro?iiu iisi'm, n il appendages

of,i£m.

llomhifx lujnthin. I. Sit',; pn>portion of the
sexes In, L 800, 804 ; pairing of, 1. 888.

Bombyas mori, difference of size of the
male and female cocoons of, L 885; pair-
ing of L 888.

Bomtujx Pemyi, proportion of sexes of, I.
:mt.

Ruiifn/r Yamamnl. i. 886; M. Porsonnat
on, f. 801 ; proportion of sexes of, 1. <V 4.

Bon aparte, C. L, on the call-notes of the
wild-turkey, 11. 58.

Bond, F„ on the finding of new mates by
crows, 11. 100.

Bom, Implements of, skin displayed In
making, L 188.

Boxes, C., on the transfer of male charac-
ters to an old female chamois, tt. 284; on
the antlers of the red deer, IL 241 ; on the
hal.its of st.iL'*. ii. -Ms; on tin- pairing of
red deer, II. 256.

Bombs, Increase of. In length and thick-
ness, when carrying a greater weight, L
112.

BoirjCET, monkey. L 185.
Boomerang, L 178.

Boreu* hyemalU, scarcity of the male, L
806.

Boet Bt Vincent, on the number of spedes
of man, L 218 ; on the colors of Labrtu

]MK»0,tt.l5.

Bo* gaunu, horns of. It. 286.
/Ami pritnitjttiiu*. ii.

Bo* tondalcu*, horns of, IL 286 ; colors of,

Botootjdos, L 1T4: mode of Hfr ot L 287 ;
Matrun inrnt of the ears and lower lip
of tli.'. ii. :!_•:,.

Boucheb de Perthes, J. C. de, on the an-
tiquity of man, L 8.

Bocebom, proportion of the sexes in a
species of PapHio from, L 801.

Bocbien, on the marriage -customs of the
savages of the Malay Archipelago, IL
857.

BoYTDJt, dewlaps of. II. 270.
Bowee-biedm. IL 98; habits of the, II. 66;
ornamental phvtng places of; L 61, ii.

108.

Bowa, use of J. 224.

\\V. \< IIMIMiHA. i. ill 5. . ,

Br ac iiYCRHiiAi.tr structure, possible ex-
planation of, I. 142.
Bnichi/wltiM, second pair of antenna? In

the male, L 827.
Beachtuea, L 828.

/{rar/nyum* calm*, scarlet face of II. 295.

Brain, of man, agreement of the, with that
of lower animals, 1. 10; convolutions ot,
in the human fietus, i. 16; larger in
homo existing mammals than In their
tertian* prototy'tcs, i. 49 ; relation of the
development of the, to the progress of
laniruayi'. i. .V> ; disease of the, atfecting
Speech, i. .V.; Intlllcnco of development
of mental faculties upon the size of the,
1. l to; Influence of the development ot
on the spinal column and skull, 1. 141;
difference in the convolutions ot, in dif-
ferent races of men, L 208.

Bkvkenr v. Dr., on the Influence of

climate, L 111.

Bbacbacil, Prof., on the quasi -religions
feeling of a dog toward his master, L 66;
on the self-restraint of dogs, i. 75.

Bracer, F, on dimorphism In NeuroUi*-
mit, L 852.

Brazii.. skulls found in caves of i. 210;
population ot L 216; compression of the
nose by the natives ot il. 885.

It re \k l>< t\v< en man and tlx ap. s. I. 192.

Bream, pro]»ortion of the sexes in the, L
299.

Bbeedtmo, age ot in birds, iL 206.
r.i:i-Ei>iN«i season, sexual characters mak-
lng their appearance in the, In birds, IL

I>i:eiim. on the effects of Intoxicating Ho-
nors on monkeys, L 12; on the recogni-
tion of women by male CyiuxxpJkaU, L
18; on revenge taken by monkeys. L it;
on manifestations of maternal affection
by monkeys and baboons. I. 89 ; on tho
Instinctive 'dread of monkeys for ser-
pents, L 41 ; on a baboon using a mat for
shelter from the sun, L 51 ; on the use of
stones as missiles bv baboons, L 50 ; on
the signal-cries of monkeys, L 55; on
sentinels posted l>v monkeys. 1. 71; on
cooperation of animals, L 72; on an
eagle attacking a young f*i r i njiffftaoaia.
i. 7 i; on luilxions In confinement pro-
tecting one of their number from pun-
ishment. L 75; on the habits of baboons
when plundering. L 75; on the diversity
of the mental faculties of monkeys, L
106; on the habits of baboons, L 186; on
polygamy in Cynoc*phalu* and r,fnuu
L 258; on the numerical proportion of
the sexes in birds, L 297 ; on the love
dance of the Black -cock, iL 48; on Pain-
fneoVa convta, IL 45 ; on the habits
of tho Black-grouse, ii. 46; on sound
produced by Birds of Paradise, IL 60; on
assemblage* of grouse, H. 97; on the
finding of new mates bv birds. 11. 102;
on the fighting of wtVI-boors, IL 251 ; on

INDEX.

395

the habits of Cynocephalm Tiamadrya.%
ii. 346.

Beent, Mr., on the courtship of fowls, ii.
113.

Breslau, numerical proportion of male
and female births in, i. 291.

Bridgman, Laura, i. 55.

Brimstone butterfly, i. 350; sexual differ-
ence of color in the, i. 396.

British, ancient, tattooing practised by, ii.
323.

Broca, Prof., on the occurrence of the su-
pra-condyloid foramen in the human hu-
merus, i. 28 ; on the capacity of Parisian
ekiilla at different periods, i. 140; on the
influence of natural selection, i. 146; on
bybridity in man. i. 212; on human re-
mains from Les Eyzies, i. 228 ; on tho
cause of tho difference between Euro-
peans and Hindoos, i. 231.

Brodie, Sir B., on the origin of the moral
sense in man, i. 60.

Bronx, II. G., on the copulation of insects
of distinct species, i. 332.

Bronze period, men of, in Europe, 1.
154.

Brown, R.. sentinels of seals generally fe-
males, i. 71 ; on the battles of seals, ii.
22!) ; on the narwhal, ii. 1281 ; on the oc-
casional absence of tho tu.sks in tho fe-
male walrus, ii. 231 ; on the bladdcr-noso
seal, ii. 265; on the colors of the sexes rn
Plvocti G'r<jenlatulica,ii. 273; on the ap-
preciation of music by seals, ii. :J17; on
plants used as love-philters, by North
American women, ii. B2&

}>r<» wn-Skqi* ari), Dr., on the Inheritance
of tho effects of operations bv guinea-
pigs, ii. 364.

Bri i i . on the use of the elephant's tusks,
il. 237.

Brulerie, P. fie la. on Die habits of M, u-

cJuut cicatricoHUH, i. :i65; on the blridu-

lation of Att iir/tuM. i. :r,:;.
BrCnnich, on the pied ravens of the lYroo

islands, il. 121.
Bryant, Captain, on the courtship of

("ttltorhinn* nrniuUM, il. 257.
Jlnlm* hixnn, thoracic projection of, I. 361.

jtuc>i>h<ilit* o^peneie, difference of the

sexes, of. In color, II.
Iiue+ro*, iiMilli atlon and Incubation of. II.
161.

fimu ro* hlt'ornU, sexual <liil, rence* In the
coloring of the cus.pie, beak, and mouth
In. II. 123.

Jlit.rro* ntrruQiitiiH, sexual illlb' r. Iiee In
the Isuk of, II. 611.

BOOH If RR, I... on il,.. origin of man. I. I ;

on tbi Miuit of 1 1 00 nj tuni , , l ie in

low savages, I. 60; on I h< f lb..

human f"ot as ■ prebeMlla organ, 1. 180;
on the mode ,,| i,,.. -i. ion ,>| i!,,. .

1. 1ST.

BC< KbAKn, V . on thn i |i ,1 prop n

Uon of the mum In mis, I. MM); on tho
nroportl r the mxm in the treat I

T.l'.i; • >n ("am ii.i iiuimUriuni, II, I J

Bccki.and, "W., on the complexity of cri-
noids, i. 59.

Buckler, W., proportion of sexes of Lepi-
doptera reared by, i. 304.

Buckinghamshire, numerical proportion
of male and female births in. i. 291 .

Bwcorax Abysxinicus, inflation of the
neck-wattle of the male, during court-
ship, ii. 69.

Budytes Iiaii, i. 251.

Buffalo, Cape, ii. 239.

Buffalo, Indian, horns of the. ii. 236.

Buffalo, Italian, mode of lighting of the,
ii. 239.

Buffon, on the number of species of man,

i. 218.
Bugs, i. 339.

Buist, P., on the proportion of the sexes
in salmon, i. 208: on the pugnacity of
tho male salmon, ii. 3.

Bulbul, pugnacity of the male. ii. 39;
display of under tail-covets bv the male,

ii. 91.

Bull, mode of fighting of the, ii. 23S;
curled frontal hair of the, ii. 269.

Bullfinch, sexual differences in the, i.
260; piping, ii. 50; female, singing of
the, ii, 51 ; courtship of the, ii. 90; wid-
owed, finding a new mate, ii. 101 : at-
tacking a reed-bunting, ii. 106; nestling,
sex ascertained by pulling out breast-
feathers, ii. 205.

Bullfinches distinguishing persons, ii.
in.-,; rivalry of female, ii. 116.

Bulls, two voting, attacking an old one,
1.72; wild, battles of. ii. 299.

BcLL-Titm t, male, coloring of, during tho
breeding Reason, II. 14.

Hi mini,, reed, bead feathers of the male,
ii. 91 : attacked by a bulllinch, ii. 106.

Hi stings, characters of young, ii. 176.

JJuji/i iih coroiiid ml um. sexes and voting of,
ii. 2ns; change of color in. ii. 221, 222.

BUM DU{ Dr., on the zebra, ii. HBj on
tho extravagance of a Irishwoman in
adorning herself, ii. o.'T ; celibacy un-
known among tho savages of South
Africa, II. !150; on the marriage-customs

of tbe Both women, ii. M7<

lit itki., on the number of species of man,

Lua

1 1 1 r it m i - 1 . color of tli.- l-eard In. II. 3iU.
Burton, ( 'aptaln, on negro id. i- ..t !. m il.i
hcautv, II. :ti0; on a iuu\. rsd Ideal of

beauty. II. ifcll.
Ill - II \|| V |. |.M.

Ill hiiwoM \N, cVtra\a;Mltt ornamental Ion

ot„. ii. nr.

BtTHiiwoMKN, hair of, I. 'Jos ; marriage cus-

HrsK. Prof. ••. on the occurrence of th.»
supra condyloid for. mien in the human

III si \iti>, throat |m>iii It of the mule, II. AA;

liiimiiilng ii.ii->. produced by a mule, u.

•W ; Indian, ear tufts of a, ||. "0.
lit nr Altl>*. ocetii i I vn il d Hen ,

mni of |h>I>k'»io> amoiit tie , I .'(Hi; lo\»

396

IXDEX.

gestures of the mole, ii. 65; double moult
in, ii. 78, SO.
Butler, A. G., on sexual differences In tho
win^s of Aricoris epitus, I. 886; on tho
coloring of the sexes in species of ThecUt^

i. -77; on tin- n'Scinlilance of IpfiittH
glaucippe to a leaf, i. 8t>l ; on the rejec-
tion of certain moths and caterpillars by
lizards and frogs, i. 404.

Butterfly, noise produced by a, i. 875;
Kmperor, i. 874, 876; meadow brown, in-
stability of the ocellated spots of, ii. 127. •

Butterflies, proportion of the sexes in, L
.■*.(>(); forcdegs atrophied in some male. i.
884; sexual difference in the neuration
of the wings of, i. 835; pugnacity of
male, i. 1574; protective resemblances of
the lower surface of, i. 879; display of
the wings by, i. 8S4; white, alighting
U|>on bits of paper, i. 887; attracted by a
dead specimen of the same species, i. Ii-*!;
courtship of.4. 887; male and female, in-
habiting different stations, 1. 888.

Buxton, C, observations on macaws, I. 78 ;
on an instance of benevolence in a parrot,

ii. 105. -

IUz/.ako. Indian hoiiev-, variation in the
crest of, B. 121.

€.

Cabbage butterflies, i. 88L

Cachalot, large head of the male, ii. 281.

Cadences, musical, perception of, by Ani-
mals, ii. 817.

Cecum, i. 26; large, in tho early progeni-
tors of man, i. 198.

i 'tiirhm viwu/into. pugnacity of the male,
ii. 89.

Callianama^ chela? of, figured, i. 820.
( nil i(nujiiiUK turn, characters of the male,
11.7.

CaUorhinu* vrninuA, relative size of tho
sexes of, 1L 248; courtship of, 1L 257.

('Ai.vn ks. aversion of to hairs on tho
face. ii. 882 ; marriage-customs of the, ii.
856.

< iilt>(,H uiyril.thrix, sexual difference In
the color of, ii. 84.

t 'am bri imjr, <>. llckard, on the sexes of
spiders, i. .'.or,.

Camel, canine teeth of nude, ii. 280. 246.

Campbell, J., on the Indian elephant I.
•J.V.i; on the proportion of male and fe-
male births in the harems of Sum. i. 'Jl'4.

i it in j/i/lo/it, riiM In iii i/riicuruH. i. "Jlis.

Canaries distinguishing persons, 1L 106.

Can abt, polygamy of the, L 261 ; change
of plumage in, after moulting. L 2s4 ; fe-
male, selecting the best slllglllg male. ii.

49 ; sterile hybrid, singing of s, it 60; fe-
male, singing of the, 11. 51; selecting s

Catoal vertebra?, number of, in macaques
and baboons, L 144 ; basal, of monkeys,
embedded in the body, L 145.

Canesteini, O., on rudimentary charscUrs

and the origin of man, I. 4 ; on rudiment-
ary characters, i. 17; on the movement
of the ear in man, i. 'JO; on the variability
of the vermiform appendage in man. 1.
27; on the abnormal division ol the malar
bone in man, i. 119; on abnormal condi-
tions of the human uterus, i. 119; on tho
persistence of the frontal suture in man,

I. 120; on the proportion of tho sexes in
silk-moths, i. 800, 802.

Canine teeth in man, i. 121; diminution
of, in man, 1. 189; diminution of. in
horses, i. 189; disappearance of, in male
ruminants, i. 139; large, in the early pro-
genitors of man, 1. 198.

Canines, and horns, inverse development
of, ii. 245.

Canoes, use of, i. 132, 226.

I ,1 ntlnllis. difference of color ill the ScXCS

of a species of, i. 855.
Cait.i:. wi/ii; proportion of the sexes In
the. i. 2'.»7: pugnacity id' the male. ii. 42;
pairing of the, ii. 47; autumn meetings
of the, ii. 52; call of the, ii. 58; duration
of the courtship of. ii. I'll; behavior of the
female, ii. 110; inconvenience of black
color to tho female, ii. 147 ; sexual differ-
< nee in coloration of the. ii. 216; crimson
e\ e -cere of the male, ii. 217 ; polvgainous,

i. '2C.;i.
Capital, i. 163.

< iiMToNin.K, < olors and nidillcation of the,

ii. 168.

Copra aqagru*, U. 288; crest of the male,
ii. 2iW; sexual difference in the color of,

ii. 275.

/ iijn; i>l us Si/u'i 1,-iim sii'„,;liu/,ttiiM, ii. 2^4.
Cai'rice, common to man and animals. 1.
62.

< ,i. ■!■;„■ i '■;>'■. in id.- by the males of

some species of, with their wines, tL 0ft

Cn/iriiiiuhjtiH \ 'injiii iitniiM, pairing of, ii.

47.

Carabid.e, bright colors of, 1. 855.
Carboknier, on the natural historv of tho

pike, L 299 ; on the relative size of tho

sexes in fishes, tL 7.
Carcitieut&t, sexual difference of color in,

II. 165.

Carcinug mama*, L 822, #28.

Carduelis eltgatut, sexual differences of

the beak in. 1L 87.
Carntvoba, marine, polygamous habits of,

1. 259 ; sexual differences In the colors oT,

ii. 278.

Carp, numerical proportion of the sexes in

the, 1. 299.
Cake, R., on the peewit, 11. 46.
Carries pigeon, late development of tho

wattle In the, L 284.
Carrion beetles, stridulation of, I. 867.
Casus, Prof. V., on the development of the

horns in merino sheep, L 280.
Cassowary, sexes and Incubation of the,

ii. 195.
Castobeum, Ii. 266.
' •iMuariiiM i/. il. n tu.". ii. I'.i.V
Cat, convoluted body in the extremity of

INDEX.

397

the tail of a, i. 29 ; sick, sympathy of a

dog with a, i. 74.
Cataract in Cebus Azara>, i. 12.
Catarrh, liability of Cebus Azarce, to, i. 11.
Catarriiine monkeys, i. 188.
Caterpillars, bright colors of, i. 402.
Cathartes aura, ii. 111.
Cathartes jota, love-gestures of the male,

ii. 65.

Catlin, G., on the development of the
beard among North American Indians,
ii. 807 ; on the great length of the hair in
some North American tribes, ii. 331.

Caton, J. D., on the development of the
horns in Cervus Virginianus and stron-
gyloceros, i. 279; on the presence of
traces of horns in the female wapiti, ii.
284; on the fighting of deer, ii. 241 ; on
the crest of the male wapiti, ii. 208 ; on
the colors of the Virginian deer, ii. 274 ;
on sexual differences of color in the wa-
piti, ii. 276 ; on the spots of the Virginian
deer, ii. 289.

Cats, dreaming, 1. 44 ; tortoise-shell, i. 274,
276, 283 ; enticed by valerian, ii. 268 ; col-
ors of, ii. 285.

Cattle, domestic, sexual differences of,
late developed, i. 281 ; rapid increase of,
in South America, i. 130 ; domestic,
lighter in winter in Siberia, i. 273 ; horns
of, i. 27s, ii. 236; numerical proportion
of the sexes in, i. 295.

Cebus, maternal affection in a, i. 39 ; grada-
tion of species of. i. 219.

C,bus Azanv, liability of. to the same dis-
eases as man. i. 11 '; distinct sounds pro-
duced by. i. 52; early maturity of the fe-
male, ii. 303.

( eh, ix v.njnuHnvK polygamous, i. 2.r)S ; sex-
ual differences of color in, ii. 277 ; hair on
the head of, ii. 291.

i i hiiH xellerosus, hair on the head of, ii.
291.

OaoiDOMYiD.K, proportion of the sexes in,
i. 305.

< BUB vcy, unknown among the savages of
South Africa and South America, ii. 850.
Ckntii-kjikh, 1. 830.

Cei'hai.oi'oiia, absence of secondary Bex-

unl character* In, 1. ;(!<*,.
Cephalopteru* ornatv*, II. 55-57.
/ ■« phalopU rw pmduHgt r, ii. 57.

(irambi/x henm, nlrtdulant organ <if, i.
«6H.

Ceratophora anpera, nasal appendag. • of
II. ML

Ceratophora Sfoddartii, nasal horn of ii.
82.

r,n; ri*. hal.lls of I. 353.
( 'errocebtu dithloim, \\ hlnkcrn, etc., of. II.
295.

Cercoplthroun, young, nel/cd l.\ :m eagle
nod resetted bv the troop, i. 7 < <l« tlnttlon

Of RpfclcM Of, I 2I'.».

Gtrcopith**u* erphtia, sexual dlllerciicc of

Cercnpithn tiH ri/iin*tiriiii nnd ar(**o-rlrl-
di*, color "i lie mtoIiimi In, II '.'77.

Cercopitheeus Diana, sexual differencea

of color in, ii. 277, 296. 297.
Cercopitheeus griseo-xiridis, i. 72.
Cercopitheeus jjetaurista, whiskers, etc.,

of, ii. 293.

Ceres, of birds, bright colors of. ii. 217.
Ceriomis Temminckii, swelling of the

wattles of the male during courtship, ii.

68.

Cervulus, weapons of, ii. 245.

Cervulus moschatus, rudimentary horns

of the female, ii. 234.
Cervus alee*, i. 279.
Cervus cam pestris, odor of, ii. 266.
Cervus Canadensis, traces of horns in the

female, ii. 234; attacking a man, ii. 242;

sexual difference in the color of, ii. 276.
Cervus elaphus, battles of male, ii. 229;

horns of. with numerous points, ii. 211.
Cervus Eldi, i. 279.
Cervus niantchuricus, ii. 2S9.
Cervus paludosus, colors of. ii. 276.
Cervus strongyloceros, i. 279.
Cervus Virgin inn us. i. 279; horns of, in

course of modification, ii. 243.
Cergle, male black-belted in some species

of, ii. 165.
Cetacea, nakedness of. i. 142.
Ceylon, frequent absence of beard in the

natives of, ii. 306.
OHABTIHCH, proportion of the sexes in the,

i. 297, 2!»-: courtship of the. ii. 90.
Ciiaki in< iiks, ii. 51 ; new mates found bv,

ii. MB.

(Iiiilciij,li,ips /tidictiN, characters of young,
ii. 177.

C/iafcoKoma atlas, sexual differences of. i.
857.

Chamecleon, sexual differences in the

genus, ii. 32.
( hamaleon hi/iircim, ii. 32. 34.
Chanurleon (hreuii, ii. 83, 84.
( ii ami.i r<i\s. ii. 81.

( ii\mois. d.iii^ei-siu-nals of, I. 71; tfHttftv
of male characters to an old female, ii.
2:w.

C ha nur petes unirolor, modified wing-

fcathar in the male. ii. 8L

CiiAi'triH, Dr.. on the transmission of sex-
ual peculiarities in pigeons, L IT4; "11
streaked Helglan pigeons, 1. 2-1, ii
150.

< iiar, male, coloring of, during the breed-
ing-season, ii. 13.

< ii m: \. I ir.s, male, developed In MMlBfL

I. 271; natural, artificial exaggeration of,
by man. 11.335; secondary sexual, trans-
mitted through both sexes. I. 270.

Charadrlu* hiatioula and j'htritiUs,

sexes and young of, II. 207.
( ii muhn "ii the Persians, II. 310.

< ii u:\i-. worn |.\ worm ii. n

Cii\KKt ah, freedom of divorce among tbr,

II. »5fl.

Chasmorhift»'hus, difference of color I*

Hie nexes'of II. 7.''. colon. ..I II 21-

tetfim Mnjr < lain ttioa <<(. 1 Hi

l IHIIIIlli: - mi d 'II!'- I'll.. • H- I .'AO.

308

INDEX.

Cheiroptera, absence of secondary sex-

ual characters in, 1. 259.
Chel.e of Crustacea, L 820, 827.
Chelonia, sexual differences in, 11. 20.
( 'IwiKtlopex ^K'ji/ptiacitK, wing-knobs of,

ii. 44.

Chera progne. 11. 80, 116.

Chest, proportions of, in soldiers and sail-
ors, 1. 112; large, of the Quechua and
Aymara Indians, i. 115.

Chevbotains, canine teeth of, il. 240.

/ lti(i*oyimthit*, stridulation of, i. ;(72.

C hi<i*uyiuithim,(Jrantii, mandibles of, i.
866.

Children, legitimate and illegitimate, pro-
I>ortion of the sexes in, i. 292.

Cuilob, lice of the natives of, i. 212 ; popu-
lation of, i. 217.

Chinwtra mon#tro*a, bony process on the
head of the male, ii. 12.

Chim.kroid fishes, prehensile organs of
male, ii. 1.

Chimpanzee, 11. 80S ; ears of the, i. 21 ; rep-
resentatives of the eyebrows in the, L
25; platforms built by the, 1. 85; crack-
ing nuts with a stone, L 49 ; hands of the,
L 188; absence of mastoid processes in
the, i. 138 ; direction of the nair on tho
arms of the, i. 185 : supposed evolution
of the, i. 222 ; polygamous and social
habits of the, 11. 845.

China, North, idea of female beauty in, il.
828.

China, Southern, inhabitants of, 1. 237.
Chinese, use of flint tools by the, i. 176:

ditlicultv of distinguishing the nice a of

the, L 207; color of the beard in, IL 804;

general beardlessncss of the, ii. 806;

opinions of the, on tho appearance of

Europeans and Cingalese, it 829, 881;

compression of the feet of, il. 886.
Chinsurdi, his opinion of beards, ii. 829,

888.

CMamydera macttlata, 11. 67.
Chloion* pedunculated eyes of tho male
of, L 882.

Chiotphaga, coloration of the sexes in, ii.
170.

Chloroccdus Tanana (figured), i. 845.
Chorda Duits vuH. i. l'.H>.
Chough, red beak of the, ii. 217.
Chbomidjk, frontal protuberance in male,

ii. 18; sexual difference In color of, IL 20.
Chn/*emye picta. long claws of tho male,

1L27.

Chryeococcyx, characters of young of, ii.

Chrytomtla ctrealis, bright colors of, i.
855.

CiiRYSOJfEi-iDJt, strldulation of, i. 867.

Oiodda pruinoea, L 841.

Cicada tepUndecim, i. 841.

Cicada, songs of the, L 840 ; rudimentary

sound-organs in females of, 1 848.
Cm atri x of • burn, causing modification

of the facial bones, i. 141.
Ctchla, frontal protuberance of male, U.

Cimetiere du Sud, Paris, L 28.

Ciiwloramjihiui cruixiUM, largo size of
male, ii. 41.

Cinclua uquaticv*, ii. 1C2.

Cingalese, Chinese opinion of the appear-
ance of the, ii. 829.

Cirripedeb, complemental males of. i. 247.

Civilization, effects of, upon natural se-
lection, i. 164; influence of, in the compe-
tition of nations, L 280.

Clanging of Geese, etc^ IL 49.

Ci.aparkde. K., on natural selection ap-
plied to man. i. l:!2.

Clarke, on the inarriogc-custonis of tho
Calmucks, IL 857.

Classification, L 181.

Claus, G, on the sexes of Soph i rind, L
826.

Cleft-palate, inherited, 1. 116.

( UiiHtcti'ri* t ri/t/tro/)*. sexes of, ii. 197.

Climate,!. Ill; coot, favorable to human
progress, L 100; power of supporting ex-
tremes of. by man, 1. 22*; want of con-
nection of, with color, L 282.

Cloaca, existence of a, in tho early pro-
genitors of man, L 198.

Cloacal passage existing in tho human
embryo, L 17.

Club, origin of the, i. 225.

Clucking of fowls, ii. 49.

Clythra ^-punctata, strldulation of, 1. 307.

Cobra, Ingenuity of a, ii. 29.

Coccus, L 179.

Coccyx, i. 2< 29; In the huninn embryo, 1.
16; convoluted body at the extremity of
the, i. 29; embedded in the body, I. 145.

Cochin-China, notions of beauty of tho
inhabitants of, ii. 829, 881.

Cock, game, killing • kite, ii. 42 : blind,

fed 1>>" its companions, i. 71; comb and
wattles of the, il. 94; preference shown
by the, for young bens, ii. 117; came,
transparent zone in tho hackles of a, ii.
180.

CocKoftherock.il. 96.

Cockatoos, il. 216, 218, 220; nestling, IL
105; black, immature plumage of ii. 180.

CtELENTERATA, absence of secondary sex-
ual characters in, L 812.

Coffee, fondness of monkeys for, i. 12.

Cold, supposed effects of 1. 118; power of
supporting, by man. i. 229.

C(.i khi-tkha. i.":;.V>; stridulant organs of,
discussed, L 869.

Collingwood, C, on the pugnacity of the
butterflies of Borneo, L 875; on butter-
flies Im-Iihj attract. -<1 |,v a dead specimen
of the same species, L 887.

Colombia, flattened heads of savages of, ii.
824.

Colonists, success of the English as, 1.

172.

Coloration, protective, in blnls. 11. 218.

Color, supposed to be dependent on light
and heat, L 111; correlation of with im-
munity from certain poisons and para-
site n, L 288; purpose of. In lepldoptera,
L 887 ; relation o£ to sexual functions, ir

INDEX.

399

flshe3, ii. 14; difference of, in the sexes
of snakes, ii. 27 ; sexual differences of, in
lizards, ii. 34 ; influence of, in the pairing
of birds of different species, ii. Ill; rela-
tion of, to nidification, ii. 159, 164; sexu-
al differences of, in mammals, ii. 272, 2S0 ;
recognition of, by quadrupeds, ii. 281;
of children, in different races of man, ii.
303; of the skin in man, ii. 364.

Colok8, admired alike by man and ani-
mals, i. 62 ; bright, due to sexual sec-
tion, i. 813 ; bright, among the lower ani-
mals, i. 313, 314; bright, protective to
butterflies and moths, i. 382 ; bright, in
male fishes, ii. 7, 13; transmission of, in
birds, ii. 152.

Colquhoun, example of reasoning in a
retriever, i. 46.

Colwnba pasnerina, young of, ii. 180.

Volymbm glacialix, anomalous young of,
ii. 202.

Comb, development of, in fowls, i. 285.
Combs and wattles in male birds, ii. 94.
Community, preservation of variations

useful to the, by natural selection, i. 149.
Composite, gradation of Bpccies among

the, i. 219.

Comte, C, on the expression of the ideal

of beauty by sculpture, ii. 363.
Conditions of life, action of changed, upon

man, i. 109 ; influence of, on plumage of

birds, ii. 188.
Condok, eyes and comb of the, ii. 124.
Conjugations, origin of. i. 59.
Conscience, i. 87, 100 ; absence of, in some

criminals, i. 88.
Constitution, difference of, in different

races of men, i. 20S.
Consumption, liability of Cebiu, Azarce, to,

i. 12; connection between complexion
and, i. 235.

CONVERGENCE, 1. 221.

Cooing of pigeons und doves, ii. 58.

Cook, Captain, on the nobles of the Sand-
wich Islands, ii. 310.

Con, B. 1)., on the dinosanria, i. 19C; on
the origin of genera, il. 206.

Cojihoti* ceyltinica, sexual differences of,

ii. 31, 84.

( <>/>/ i/<, i. 859.

I 'I'/iriH IhIiIih, sexual differences of. i. 85-1.
Copri* In Tutrix, stridulatiou of i. 809.

Corals, bright eoton of, i. 818.

< OHAI. SNAKES, II. 29.

( orih/fim, sexual difference of colcr In a

•BOOM of, II. 84.
Connr, habits of the chaffinch In, I. 298.

COBNKMUB, OD the projMirtloliH of lh„ s, \, s

lii l.ufiiiniH (VrriiH, I. 805.
Oobfoba Wou'I'iana, L 199; agreement

of with (hi kldneyi offlthet, L 16,
Oonnutran variation, L 126.

CoitKKI.ATION, InlliK lK o of, In the prodnc-
tlon of Hires I. 28*.

COIIHK. Oil the lliotle of fUrhtll r the ele

phtm, II. 246,
Cvrru* cnri>ii, . II. |ihi
Cm-run ji-xu-uhm. red ik of, II 'J17.

Cornus pica, nuptial assembly of, ii. 98.
Corydalis cornutue, large "jaws of the

male, i. 332.
Cosmetornu, ii. 173.

Cosmetornis vexillarius, elongation of
wing-feathers in, ii. 69, 92.

Cotingidjs, sexual differences in, i. 260;
coloration of the sexes of, ii. 169; resem-
blance of the females of distinct species
of ii. 184.

Cottus scorpim, sexual differences in, ii. 9.

Counting, origin of, i. 174 ; limited power
of, in primeval man, i. 226.

Courage, variability of, in the same spe-
cies, i. 39 ; universal high appreciation
of, i. 91 ; importance of, i. 150; a charac-
teristic of men, ii. 313.

Courtship, greater eagerness of males in,

i. 263 ; of fishes, ii. 2 ; of birds, ii. 47, 96.
Cow, winter change of the, ii. 284.
Crab, devil, i. 323.

Crab, shore habits of, i. 322.

C'rabro cribrarius, dilated tibia; of the

male, i. 333.
Crabs, proportions of the sexes in, i. 807.
Cranz, on the inheritance of dexterity in

6eal-catching, i. 113.
Crawfurd, on the number of species of

man, i. 218.
OremAlabruH mam and C. melops, nests

built by, ii. 19.
Crest, origin of, in Polish fowls, i. 275.
Crests, of birds, difference of, in the sexes,

ii. 181; dorsal hairy, of mammals, ii. 2»»>.
Cricket, field-, stridulatiou of the, i. 842;

pugnacity of male, i. 849.
Cbiokxt, house-, stridulatiou of the, i. 842,
849.

Crickets, sexual differences in, i. 850.
OxXOCOUUBJt, stridulatiou of the, i. 367.
Crinoids, complexity of, i. 59.
Croaking of frogs, ii. 25.
Crocodiles, musky odor of, during the

breeding-season, ii. 27.
Ckocopii.ia, ii. 27.

Crossbills, characters of young, ii. 17(5.
Crushes in man, i. 217.
Crossing of races, effects of the, i. 282.
CroHHojitilon aiu-itiun, ii. >:i. 15s, 1-7;

adornment of both sexes of, i. 2-Ml; sexes

alike In, ii. llo.
CroT( ii, C. It., on the stridulatiou of bee-

ties. I. 867, 87ii ; on the Mridulation of

Hmopatkm,lvn\ on the itridulntton

of .■!<•. ///,*. i. 872.
Crow Indians, long hair of the, 11.881.

t i.ow, joong of the, ii. 600,

Cuowsjl. 216; voenl organs of the, ii. 52;

(Mug in triplets, DL l<>2.
Crows, canion, new mates found bv, II.

loo.

CuoWK, Indian, feeding their blind coin-

ptnloni, L 1 1.

Cm nn of suvurct to animal*, I. 91.
Citi'HT ack a, amphl|NMl, mule-, -.•xiiillx ma

tore while jroang.ll 106; pnrwitto\ Iom

of limbs by n-mule, I. 217; pr, hi null*
fret and anti nn.e of. I 21- , male. m.<i«

400

INDEX.

active than female, I. 268; parthenogen-
esis In, i. 807; secondary sexual charac-
ters of; i. 81S; auditory hairs of ii. 817.

Crystal worn in tin- lower lip l.y .-nine
Central African women, ii. <V1'>.

Ctckoo fowls, i. •.'<>.

Cuucn> m, L 246, 889.

Cpllkn, Dr., an the throat-pouch of the
male bustard, ii. 55.

C cultivation of plants, probable origin of,
i. 161.

Ccpim.ks, *\r^ on the numerical proportion
of the sexes in dogs, sheep, and cattle, 1.
294, 295; on the Scotch deerhound, iL
249; on sexual preference in dogs, iL
259.

Cuactruomn js, sexual difference in length
of snout in some, i. 247; hornlike pro-
cesses in male, i. 8C2; musical, i. 800,

Ci kiosity, manifi stations of, bv animals,
L 41.

Ccrlews, donble moult in, ii. 77.

CrRsiiiiKs. comparative absence of sexual
difference among the, L 261.

Ccbtis, J., on the proportion of the sexes
in Athalia, 1.805.

Ccvieb, F., on the recognition of women
by male quadrumana, 1. 18.

Ccvieb, G„ views of, as to the position of
man, L 188; on instinct and intelligence,
i. 86; on the numlter of caudal vertebra)
in the mandrill, i. 144 ; on the position of
the seals, i. 1NJ ; on /ftrtocoti/le, I. 816.

Cmm*<iUa etiecicti, sexual differences of.
11.187.

Ci/amih'tjon. sexual difference In colors
of, U. 165; immature plumage of ii. 180.

CijchruA, sounds produced by. L 870.

(i/riniti tin mfirti, sexual ditleretice of col-
or in, L 886.

Oygnwt femiA, trachea of II. 57.

Ouonus olor, white young of 11. 202.

Cytlo Ijeda, instability of the ocoUated
spots of, IL 127.

< u»<inthuK variation in the genus ii.
120.

Cvnipidjs, proportions of the sexes In, L
805.

Cynocephalu*, difference of the young,
from the adult, 1. 18 ; male, recognition
of women by, L 18 ; polygamous habits
of species of, L 258.

Cynoctphalm chaema, L 40.

Cifnocephalm gelada, L 50.

( i/n<M;i,h,ihiM tiiiinmtri/o*. i. .'hi; t>. \u:il

difference of color in, IL 278.
Ci/n<«'i )>haluM lriico]>hu\ colors of the

sexes of, iL 278.
Cifnoctphalu* mormon, colors of Uie nude,

U. 278, 282, 296.
Ctjnocephalut porcarius, mane of the

male 11.255.
Pvpridtna, proportions of the sexes In, 1.

807.

C ycri n m.r, proportion of the sexes In the,

1. 299.

i 'ti'bimi>.», Indian, IL 17.

Ctprixoi>ontid.f., sexual differences in
the, 11. 7, 9.

< 'i/printiM a it rat it*. 11. 16.

< i/jainim /t/ioj-in iim. spawning of 11. 15.
( i/jo-im. relations of the sexes in, i. :>0T.

( 'yttophora cri«tata, hood of, 11. 265,

Dactlo, sexual difference of color in, iL
l

Ihirtlo (iaudirfmudi, young mnle of, IL
180.

Pal-kip a, a kind of ptarmigan, I. 297.
JhiiimliH ulhifn'H*, peculiar markings of,

ii. 287.

Domalit pyffarga, peculiar markings of,

IL 287.

Dampness of climate, supposed influence

of, on the color of the skin, I. Ill, 288.
Thuit tiihr. i. :tTt'>.
Dances of birds, iL 65.
Dancing, L 224.

Daniell, Dr., his experience of residence
in West Africa, L 286.

Darfcr, protuberances artillclally pro-
duced in. ii. 228.

Darwin. F.. on the stridulation of Ihr-
m*#tt* muriniiA, L 868.

Jkuychira pudibunda, sexual difference
of color in, 1. 886.

Davis, A. H., on the pugnacity of the male
stag-beetle, L 864.

Davis. .1. I!.. on the capacity of the skull
in various races of men, i. 140; on the
hear.lv of the I'oh nesians. ii. :{<M>.

Death-rate higher in towns than in rural
districts, L 169.

Death-tick, L 878.

Db Candollk, Alpb- on a case of Inherited

power of moving the scalp, i. 19.
Dkclknsions, origin of, L 59.
Dkookation in birds, ii. 68.
DectiettA, L 845.

Du n. spot- of voting, ii. 17''«. '.'ss ; horns
of. ii. use of bonis of, II. 240,

251 ; size of the horns of il. 247: female
pairing with one male, while others are
fighting for her, u. 256; male, attracted
by the voice of the female, ii. ; male,
odor emitted by, IL 266 ; development of
the horns in, L 278 ; horns of a, in course
of modification, IL 248.

Dekk, Axis, sexual difference in the color
of the, il. 276.

Dekk, fallow, different colored herds of IL
281.

Deer, Mantchnrian. II. 289.
Deer, Virginian, iL 2X9 ; color of the, not
affected by castration, IL 274; colors of,

U. 276,

Drbrhopnd, Scotch, greater size of the

male, I. 288, U. 254.
Defewbivb organs of mammals, iL 251.
De Geek, C on a female spider destroying

a male, 1. 829.

INDEX.

401

Per ay, Dr., on the bladder-nose seal, ii.
265.

Pemerara, yellow fever in, i. 234.

Dendrocygna, ii. 1T7.

JJendrophila frontalis young of. ii. 211.

Denny, II., on the lice of domestic ani-
mals, i. 211.

Uermestes murinus. stridulation of. i. 303.

Descent traced through the mother alone,
ii. 848.

Deserts, protective coloring of animals
inhabiting, ii. 214.

Desmarest. on the absence of suborbital
pits in Antilope fmbyutturoHa, ii. 207;
on the whiskers of Maeaciw, ii. 269; on
the color of the opossum, ii. 275; on the
colors of the sexes of Mm minutw, ii.
273; on the coloring of the ocelot, ii.
273: on the colors of seals, ii. 273; on
Antilope caama, ii. 275; on the colors
of goats, ii. 276; on sexual difference of
color in Atelex mitrgiiuttus, ii. 277; on
the mandrill, ii. 278; on Macacws cyno-
rnolfpiH, ii. 303.

Desmoulins. on the number of species of
man. i. 2X8; on the musk-deer. ii. 267.

Deskr. on the imitation of man by mon-
keys, i. 42.

DISPUTE, P.. on criminals destitute of con-
science, i. 89.

Development, emhrvonic, of man. i. 14,
16; correlated, ii. 125.

Demi., not believed in by the Fuegians, i.
65.

Devil-crab. i. 323.

Devonian fossil insect from the. i. 319.
Dewlaps, of cattle and antelopes, ii. 270.

ZHadema, texnaT differences of coloring in
tlw species of. i. 376.

Diastema anomala, inimi-ry by the fe-
male of, i. 400.

Dtadema boUna, i. 400.

Di a mono- beetles, bright colors of i. 855.
Diastema, occurrence of. in man. i. 121.
DiASTYi.m.K, proportion of the sexes in, 1.
301.

DioDonus, on the absence of beard in the

natives of Ceylon, ii. 306.
JMcrunui, racket shaped feathers in, ii. 7";

uldillcutiou of II. 160.
JHvruruMmacrocercuM, change of plumage

In. II. 171.

JHilelphU opoMMiim, sexual dill'.rence in

the color or, II. 272.

Dikkkukxckh, comparative, belwc. n <im. r-
ent species of birds of the same s. \, ii.

184,

Dm. ns. utipcriiiiiiier.irv . more frequent In
nun than in women. I. 865; luporna*

inerarv, Inherltai f. I JT<>; supermi-
ni, rarw early developim nl of, I. 2s2,
DlMOKPIIUM, In frinalen of wati i licctlc*, I.
:t.i:t; In Xrumf/n huh and . I »/'"'«, I

Hi

JH/.rli. u* C,int„i i, ■ c\ual dlln n lie. of
I. it.'.s.

DlI'Lopon \, nndu ri lie limbs of il uile

I. IN,

Dipsas cynodon, sexual difference in the

color of, ii. 28.
Dipteba, i. 338.

Disease, generated by the contact of dis-
tinct peoples, i. 230.

Diseases common to man and the lower
animals, i. 11 ; differences of liability to,
in different races of men, i. 208; new,
effects of upon savages, i. 229 ; sexually
limited, i. 283.

Display, coloration of Lepidoptera for. i.
383 ; of plumage by male birds, ii. 82, 91.

Distribution, wide, of man, i. 131; geo-
graphical, as evidence of specific distinct-
ness in man, i. 210.

Disuse, effects of. in producing rudiment-
ary organs, i. 18; and use of parts, ef-
fects of, i. 112; of parts, influence of, on
the races of men, i. 238.

Divorce, freedom of, among the Charruas,
ii. 856.

Dixon, E. S.. on the habits of the guinea-
fowl, i. 261 ; on the pairing of different
species of geese, ii. 109 ; on the courtship
of peafowl, ii. 116.

DOBBIZHOFFKB, on- the marriage-customs
of the Alipones, ii. 357.

Dogs, suffering from Tertian ague, i. 13;
memory of, i. 43 ; domestic, progress of,
in moral qualities, i. 49: distinct tones
uttered by. i. 52; parallelism between his
affection ibr his master and religious feel-
ing, i. 65; sociability of the. i. 71 ; sym-
pathy of. with a sick cat, i. 74 : sympathy
of. with his master, i. 74; possible use of
the hair on the fore-legs of the, i. 1&5;
races of the. i. 221 : diverging w hen draw-
ing sledges over thin ice, i. 4.">; dreaming,
i. 41. 152; exercise of reasoning faculties
by, i. 47; their i>osscssion of conscience,

i. 75; numerical proportion of male and
female births in, i. 294 ; sexual affection
between individuals of. ii. 868; howling
at certain notes, ii. : i 1 T ; rolling in carrion,

ii. B6T.

Doit. no< u-ii a i.ir structure, possible cause
of i. 1 12.

1 (olpiiins, nakedness of i 1 12.

Domestic animals, races of, i. 221 ; change
of breeds of, ii. 3.72.

DoMKsm \ i ion. iutlui ni f. iii ivmo> lug

the sterility of hybrids, L 21 1.

D'OiuiniNY, A., on (lie Influence of damp-
ness and dr\ in ss on the color of the skm,
i. 232: on tlie Yuracaras, il. :131.

Do i im'.ki, II. 195.

Dot'ill.KOAY, K., • > r ■ sexual different . - in
the Wlllgs of blltterllies, I. Hi,

Dorni.KiiAv. II.. on the pn>| tort Ion of tin.
sexes iii tM smaller moths, I. 801 ; on (he
attraction of the males of /.<m<<kv/»i/hi
i/mn uM and .^itnrniii r<irj>ini lit thu
female, I. IttKi ; on (he proportion of tlw

sex. s III the l^ pldopteni. J. 808 [ nil til.'

ticking of A,,,.).,,,,,, fifiiffnfum, I. Iff;

on the st met lire of Ayrroitiii /noiii i \
H75; on white butlcrlll. » alighting u|h>ii
paper, I. .'ITs.

402

INDEX.

Douglas, J. W., on the sexual differences
of the Hem iptera. i. 339 ; on the colors
of British Ilomoptera, i. 841.

Down, of birds, ii. 77.

Draco, gular appendages of, ii. 31.

Dbagonet, Gemmeous, ii. 7.

Dbagon-flies, caudal appendages of male,
L 884 ; relative size of the sexes of, i. 387 ;
difference in the sexes of, i. 851 ; want of
pugnacity by the male, i. 858.

Dbake, breeding plumage of the, il. 81.

Dreams, i. 44 ; a possible source of the be-
lief in spiritual agencies, i. 64.

Drill, 6exual difference of color in the, ii.
278.

Dromceus irroratu*, ii. 196.
l>romokeay Baharan species of, ii. 164.
Deongo shrike, ii. 171.
Dbongos, racket-shaped feathers in the

tails of, ii. 70, 80.
Dbyness, of climate, supposed influence of,

on the color of the skin, i. 283.
Dryojritheeu*, i. 191.

Duck, harlequin, age of mature plumage in
the, ii. 204; breeding in immature plu-
mage, ii. 205.

Duck, long-tailed, preference of male, for
certain females, ii. 117.

Dcck, pintail, pairing with a wigeon, ii.
109.

Duck, voice of the, ii. 57 ; pairing with a
shield-drake, ii. 109 ; immature plumage
of the, ii. ISO.

Duck, wild, sexual differences in the, i.
260; speculum and male characters of,
i. 2S1 ; pairing with a pintail drake, ii.
110.

Ducks, dogs and cats recognized by, ii. 106 ;

•wild, becoming polygamous under partial

domestication, i. 261.
Dugong, tusks of, ii. 281 ; nakedness of, i.

142.

Dujakdin, on the relative size of the cere-
bral ganglia in insects, i. 139.

Duncan, Dr., on the fertility of early mar-
riages, i. 167.

Dupont, M-, on the occurrence of the su-
pra-condyloid foramen in the humerus
of man, i. 28.

Duband, J. P., on causes of variation, i. 109.

Dubeau de la Malle, on the songs of birds,
L 58 ; on the acquisition of an air by black-
birds, IL 52.

Dutch, retention of their color by the, in
South Africa, i. 233.

Dutt, sense of, i. 67.

Dutaucel, female Hylobatet washing her

young, i. 89.
Dyaks, pride of, in mere homicide, i. 90.
DytuutM, large size of males of, L 837.
Dtnastinl Btrid ulation of, i. 369.
Dyii*cus, dimorphism of females of. L 833;

grooved elytra of the female, L 833.

B.

Eagle, young CercnpiUitcut rescued from,
by the troop, L 72.

Eagle, white-headed, breeding in imma-
ture plumage, ii. 205.

Eagles, golden, new mates found by, ii.
100.

Eab, motion of the, 1. 20 ; external shell of
the, useless in man, i. 21 ; rudimentary
point of the, in man, L 21.

Ears, piercing and ornamentation of the,

ii. 825.
Echidna, i. 193.

Echini, bright colors of some, i. 813.

Echtnodebmata, absence of secondary sex-
ual characters in, i. 312.

Eckeb, figure of the human embryo, i. 15;
on sexual differences in the pelvis in man,
ii. 802 ; on the presence of a sagittal crest
in Australians, ii. 804.

Edentata, former wide range of, in Amer-
ica, i. 211 ; absence of secondary sexual
characters in, i. 259.

Edolius, racket-shaped feathers in, ii. 70.

Edwabdb, Mr., on the proportion of tho
sexes in North American species of l'a-
piUo, i. 801.

Egeeton, Sir P., on tho use of the antlers
of deer, ii. 241 ; on the pairing of red deer,
ii. 257 ; on the bellowing of stags, il. 261.

Eggs, hatched by male fishes, ii. 19.

Egbet, Indian, sexes and young of, ii. 208.

Egbets, breeding plumage'of, li. 78 ; white,
ii. 218.

Ehbenbebo, on the mane of the male Ha-

madryas baboon, li. 255.
Ekktkom, M., on llarclda glacial!*, ii. 117.
Elachusta t-ufocinerea, habits of male, i.

808.

Eland, development of the horns of the, i.

2S0.

Elands, sexual differences of color In, il.
274.

Elaphomyia, sexual differences in, I. 888.
Elaphru* u/iyinottus, stildulation of, i. 368.
Elap», ii. 80.

Elatebid^e, proportions of the sexes in, 1.

805.

Elatebs, luminous, 1. 835.

Elephant, i. 193; nakedness of the, i. 145;
rate of increase of the, 1. 180; Indian,
polvgamous habits of the, i. 259 ; pugna-
city of the male, ii. 229 ; tusks of. ii. 231,
282, 237, 247 ; Indian, mode of fighting,
of the, ii. 245 ; male, odor emitted by the,
ii. 266; attacking white or gray horses,
ii. 281.

Elevation of abode, modifying Influence
of, i. 116.

Elimination of inferior individuals, i. 165.
Elk, ii. 287 ; winter change of the, iL 284.
Elk, Irish, horns of the, ii. 247.
Ellice Islands, beards of the natives, ii.

807, 888.

Elliot, R., on the numerical proportion of
the sexes in young rats, 1. 296 ; on the
proportion of the sexes in sheep, i. 296.

Elliott, D. G.. on Pelccantu er^thro-
rhynchv*, il. 77.

Elliott, Sir W., on the polvtramous hab
its of the Indian wild -friar, L 259.

INDEX.

403

Ems, on the prevalence of infanticide in
Polynesia, ii. 347.

Elphinstone, Mr., on local differences of
stature among the Hindoos, i. 110; on
the difficulty of distinguishing the native
races of India, i. 207.

Elytra, of the females of Dytiscus, Aci-
Ku8, Ilydroporm, i. 338.

Emberiza, characters of young, ii. 176.

Emberiza miliaria, ii. 177.

Emberiza schoeniclux, ii. 106 ; head-feath-
ers of the male, ii. 91.

Embryo of man, i. 14, 15; of the dog,
i. 15.

Embryos of mammals, resemblance of the,
i. 81.

Emigration, i. 166.

Emotions experienced by the lower ani-
mals in common with man, i. 38 ; mani-
fested by animals, i. 41.

Emperor moth, i. 385.

Emulation of singing-birds, ii. 50.

Emu, sexes and incubation of, ii. 196.

Endurance, estimation of. i. 91.

Energy, a characteristic of men, ii. 313.

England, numerical proportion of male
and female births, in, i. 291.

Engleiteart, Mr., on the finding of new
mates by starlings, ii. 101.

English, success of, as colonists, i. 172.

Engravers, short-sighted, i. 113.

Entomostraca, i. 823.

Entozoa, difference of color between the
males and females of some, i. 312.

Eocene, possible divergence of man dur-
ing the, i. 192.

EoLiDiE, colors of, produced by the biliary
glands, i. 314.

Epeira, i. 828.

Ejicira nigra, small size of the male of, i.
829.

Ephemerae, i. 331.

EPIIEMERIDiE, i. 350.

Epiiemerina, i. proportions of the sexes
in, i. 306.

BpMmngcr titium, strklulating organs

of, i. 344, 848.
Epicalia, sexual differences of coloring in

the species of, i. 376.
E*piitM /mmionuH. winter change of, ii. 2S4.
Erateina, coloration of, i. 8*5.
Erkct attitude of man, i. 136.
EmEBXOHTL on the development of hair in

man, 1. 24; on a lannguionB mustache

in a female fata*, i. 25; on the want of
definition between the scalp and the fore-
head in wiiiic children, I. I Mi; on the ar-
rangement, of tho hair in the human

fetus, 1. 1*6; on Hie hairiness of (lie face
in the human lotus of both §0*08, ii. 862,
MB.

Esmeralda, difference of color in the sex-

M of. L 856.
Exnx hiciuM, 1. 299.
Ei<itr ntiriiliiliiH. il. 1 I.

Esquimaux, I. 161, 160; their belief In the
Inheritance of doxterltj in seal catching,

i. 118; mode of life of.'i. 287.

Estrelda arnandava, pugnacity of the

male, ii. 46.
Eubagis, sexual differences of coloring in

the species of, i. 377.
Euchims longimanm, sound produced

by, i. 370.
Endromias morinellm, ii. 194.
Eulampis jugularis, colors of the female,

ii. 160.

Euler, on the rate of increase in the Uni-
ted States, i. 126.

Eurnomota mperciliarU. racket-shaped
feathers in the tail of ii. 70.

Eupetomena macroura, colors of the fe-
male, ii. 160.

Euphema splendida, ii. 166.

Euplocarnus erythrophthalmm. posses-
sion of spurs by the female, ii. 44.

Euplvea raidamas, mimickry of, by the
female of Diadema anamala, i. 400.

Europe, ancient inhabitants of, i. 22S.

Europeans, difference of, from Hindoos,
i. 231 ; hairiness of, probably due to re-
version, ii. 361.

Eurostopodm, sexes of, ii. 197.

EurygnatJius, different proportions of tho
head in the sexes of i. 334.

Eufftephanus, sexual differences of species
of, ii. 37 ; young of, ii. 211.

Exaggeration of natural characters by
man, ii. 334.

Exogamy, ii. 344, 348.

Expression, resemblances in, between
man and the apes, i. 184.

Extinction of races, causes of, i. 229.

Eye, destruction of the. i. 112; change of
position in. i. 141 ; obliquity of, regarded
as a beauty by the Chinese and Japan-
ese, ii. 828.

Eyebrows, elevation of, 1. 19; develop-
ment of long hairs in, i. 24; in monkeys,

i. 185; eradicated in parts of South
Ameiiea and Africa, ii. 324; eradication
of, by the Indians of Paraguay, ii. 332.

Eyelids, colored black, in part of Africa,

ii. 323.

Eyklarhes, eradication of, by the Indians
of Paraguay, ii. 332.

Eyks. difference in the color of, in the sex-
es of birds, ii. 123; pillared, of the male
of C/doeon, I. 881.

Evton, Ti C!., observations on the develop-
ment of the horns in the fallow-deer, i.
279.

ETCH, Les, human remains from, i. MB,

P.

Eaiiki:, M., on the habits of < | /v< /•/.»■. I.

:<:•!».

Facial bones, causes of modification of
the. i. III.

Faoui.tikh, mental, variation of. In tho
Mine species, L 3.*>; diversity of. hi tho
Hume nice of men, i. lo.'p; Inheritance of,
L 106; dhersilv Of, III animals of tho
name species, I. IOC; of bird*, II. 104.

404

INDEX.

Fakirs, Indian, torturt-s undergone by, 1.
92.

Fitlco leiicocephaluK, ii. 205.
Fah'o jtereyriiiHK ii. 100. 179.
Falvo tinnunenhm, ii 100.
Falcon, peregrine, new mate found by, ii.
100.

Falconer, II., on the mode of fighting of
the Indian eicphant, Ii. 245; on canines
in a female deer, ii. 246; on Ilyomoudiu*
aqimticux, ii. '_'•><».

Falkland islands, horses of i. 227.
Fallow-deer, different colored herds of,
ii. 281.

Famines, frequency of, among savages, 1.
229.

Farr, Dr., on the structure of the uterus,
i. 118; on the effects of profligacy, i. 166;
on the influence of marriage on " mortali-
ty, i 169.

Farrar, F. TV., on the origin of language,

i. 54; on the crossing or blending of lan-
guages, i. 58 ; on the absence of the idea
of God in certain races of men, i. 68 ; on
early marriages >f the poor, i. 167; on
the middle ages, i. 172.

Fashions, long prevalence of, among sav-
ages, ii. 827, 886.

Faye, Prof., on the numerical proportion
of male and female births in Norway and
Russia, i. 291 ; on the greater mortality
of male children at and before birth, i.
292.

Feathers, modified, producing sounds, ii.
60; et eeqq~, 156; elongated, in male
birds, ii. 69, 93; racket-shaped, ii. 70;
barbless and with filamentous barbs in
certain birds, ii. 70 ; shedding of margins
of, ii. 82.

Feeding, high, probable influence of, in
the pairing of birds of different species,

ii. 111.

Feet, modification of. in man, L 136; thick-
ening of the skin on the soles of the, L
113.

Ft/ in Canadtnrt*, throat-ruff of ii. 273.
Ft/ in fnirflrt/i'M and /•'. /«/</*. sexual diffcr-

ences in the coloring of, ii. 278.
Female, behavior of the, during courtship,

i. 264.

Female birds, differences of, ii. 185.

Females, presence of rudimentary male
organs in, i. 199 ; preference of, for cer-
tain males, i. 254; pursuit of, by' males,
i. 263; occurrence of secondary sexual
characters in, i. 267; development of
male characters by, i. 271.

Females and males, comparative mortali-
ty of, while young, i. 255, 267; compara-
tive number's of. i. 252. 255.

Femce and tibia, proportions of, in the
Aymara Indians, i. 115.

Ferguson, Mr., on the courtship of fowls, 11.
118.

Fertilization, phenomena of, in plants, i.
265; in the lower animals, i. 266.

Fevers, immunity of Negroes and Mulat-
tocs from, L 234.

Fiher sibethieua, protective coloring of, ii.
2>4.

Fidelity of savages to one another, i. 91 ;
importance of, i. 156.

Field-hlaves, difference of, from house-
slaves, i. 237.

Fijians, burying their old and sick parents
alive, i. 74; estimation of the Iteard
among the, ii. 833; admiration of, lor a
broad occiput, ii. 335.

Fiji Islands, beards of the natives, ii. 806,
883; marriage-customs of the, ii. ;J56.

Filial affection, partly the result of uatu
ral selection, i. »7.

Kn. r.M terminale, i. '29.

Finch, racket-shaped feathers In the tail
of a, ii. 70.

Finches, spring change of color in, ii. 82;
British females of the, ii. 185.

Fingers, partially coherent, in species of
Hylobafts, i. 134.

Finlayson, on the Cochin-Chinese, ii. 329,

Fire, use of, i. 132, 176, 225.

Fischer, on the pugnacity of the male of
/.< tin us ctjihitlote*, i. 865.

Fish, proportion of the sexes in, i. 298;
eagerness of male. i. 263.

Fishes, kidneys of, represented by Cor-
pora Wollliana in the human embryo. 1.
16; male, hatching ova in their mouths,
i. 202; receptacles for ova possessed by,

i. 246 ; relative size of the sexes in. ii. 7 :
fresh-water, of the tropics, ii. IT; protec-
tive resemblances in, ii. IS; nest- build-
ing, ii. 19; spawning of, ii. IS; sounds
produced bv. ii. 22, 315; continued
growth of, ii." 207.

Fltaror pollicis longus, similar variation

of, in man, i. 124.
Flint tools, i. 176.

Flints, difficulty of chipping into form, i.

188.

Florida, Qui*cahut nutjor in, 1. 298.

Flounder, coloration of the, ii, 18.

Flower, W. H., on the abductor of tho
fifth metatarsal in apes, i. 123; on tho
position of the Seals, i. 1-3; on the
throat-pouch of tho male Bustard, ii.
55.

Fly-catchers, colors and nidiflcation of,

ii. 162.

FuiTUS, human, woolly covering of the, i.
25 ; arrangement of the hair on, L 188.

Food, influence of, upon stature, i. 110.

Foot, prehensile, in the early progenitors
of man, L 198; prehensile power of the,
retained In some savages, i. 136.

Fon vmi n. supra-comh loid, exceptional oc-
currence of. in the humerus of man, i. 27,
125 ; In the early progenitors of man, L
198.

Forbes, D«, on tho Aymara Indians, L
115; on local variation of color in the
Quechuas, i. 287 ; on the hahiessness of
the Aymaras ami (Juediuas. ii. 8n7 ; on
the long hair of the Aymaras and Quo-
chuas. ii. 805, 831.

Fob el, F^ on white young swans, iL 202.

INDEX.

405

Formica rvfa, size of the cerebral ganglia
in, i. 139.

Fossils, absence of, connecting man with

the apes, i. 193.
Fowl, occurrence of spurs in the female,

i. 271 ; game, early pugnacity of, i. 285 ;
Polish, early development of cranial pe-
culiarities of, i. 285; variations in plu-
mage of, ii. 71; examples of correlated
development in the, ii. 124; domestic,
breeds and subbreeds of ii. 168.

Fowls, spangled Hamburg, i. 272, 284;
■exual peculiarities in, transmitted only
to the same sex, i. 274 ; loss of secondary
sexual characters by male, i. 275; inher-
itance of changes of plumage by, i. 272 ;
Polish origin of the crest in, i. 275 ; period
of inheritance of characters by, i. 284 ;
cuckoo-, i. 285; development of the
comb in, i. 285; numerical proportion of
the sexes in, i. 296; courtship of, ii. 112;
mongrel, between a black Spanish cock
and different hens, ii. 125; pencilled
Hamburg, difference of the sexes in, ii.
151 ; Spanish, sexual differences of the
comb in, ii. 151 ; spurred, in both sexes,

ii. 155.

Fox, W. D., on some half-tamed wild-
ducks becoming polygamous, and on
polygamy in the guinea-fowl and canary-
bird, i. 261; on the proportion of the
sexe6 in cattle, i. 295 ; on the pugnacity
of the peacock, ii. 43; on a nuptial as-
sembly of magpies, ii. 98; on the finding
of new mates by crows, ii. 100 ; on par-
tridges living in triplets, ii. 103; on the
pairing of a goose with a Chinese gander,
ii.110.

Foxes, wariness of young in hunting dis-
tricts, i.4S; black, ii. 280.

France, numerical proportion of male and
female births in, i. 292.

Francesco, B., on the Simian resemblances
of man, i. 4.

Fkahee, C, on the different colon of the
sexes in a species of Sqvilla, i. 326.

Fringilla ctumabfaia, ii. 82.

JPrtnotUa oiriiagt of mature plunuura in,

ii. 204.

Frinyilla ryanea, age of mature plumage
in, ii. 2(4.

FHkffU/n Iruvoph ;•//*, young of, ii. 208.

FrmffiUo tpttHM, ii. llo.

FriiKjilhi trixti*, change of color in, in

spring, il. S2; young of. ii. 207,
VahniuxDM, resemblance of the females

of distinct special of, ii. 184.
Fbom, 11.21; mule, temporary raoeptadoa

for ova possessed hy, i. 246; ready to
breed before tin- females, I. 252; vocal
organs of, II. 2-i.
Fhontai. hone, persistence of the suture
In. I. 12(1.

Fki'ith, poisonous, avoided by animals, I.
80.

fOMiim,! 160, L74: mental capacity of
the, 1. :;:!; qnoal reUfftoni sentmx sta of
the, i. 69; power of sik-iit in the, i. 111-

skill of, in stone-throwing, i. 156 ; resist-
ance of the, to their severe climate, i.
150, 229 ; difference of stature among the,

i. Ill ; mode of life of the, i. 237; resem-
blance of, in mental characters, to Euro-
peans, i. 223 ; aversion of, to hair on the
face, ii. 332; said to admire European
women, ii. 334.

FULGOBID.E, songs of the, i. 340.

Fits, whiteness of, in arctic animals, in

winter, i. 273.
Fur-bearing animals, acquired sagacity

of, i. 48.

G.

Gallicrex, sexual difference in the coloi of

the hides in. ii. 123.
G allicr ex crista tu.% red caruncle occurring

in the male during the breeding-season,

ii. 76.

Gallinace/E, frequency of polygamous
habits and of sexual differences in the, i.
260 ; love-gesture's of. ii. 65 ; decomposed
feathers in, ii. 70 ; stripes of young, ii.
176; comparative sexual differences be-
tween the species of, ii. 1S4, 185; plu-
mage of, ii. 187.

Gallinaceous birds, weapons of the male,
ii. 42; racket-shaped feathers on the
heads of ii. 70.

GalHnula chloropm, pugnacity of male,
ii. 88.

Gallinula cristata, pugnacity of the male,
ii. 39.

Galloperclix, spurs of. ii. 44 : development

of spurs in the female, ii. 155.
Gallophaxix, young of. ii. 1S2.
GalliiH bankica, ii. 151 ; neck-hackles of,

ii. 81.

G alius Stanleyi, pugnacity of the male, ii.
42.

Galls, i. 146.

Galton, Mr., on the struggle between the
social and personal impulses, i. 99; on

hereditary genius, i. 106: on the effects

of natural selection on civilized nations,
i. 161 ; on the sterility ol* sole daughters,
i. 164; on the degree" of fertility of people
of genius, i. 165; on the early marriages
of the poor, i. Km; on the ancient (I reeks
L 171 ; on the Middle Ages. i. 171 ; on
the progress of the United Slates, i. 17.*;
on South African notions of beautv, ii.

661.

Gamtnaru*, use of tin' cliche ol. i. :'. '.1.

Gam ma run marinu*, I. 82^.

<i ism is, while oiilv When mature, Ii. 2K

(Jan ci, I. 196.

<;as. .11. babes, i. 804

Gaoitk, hoi lis of the, ii 2.16.
(•AC between man and the noes. I. 192.
§!!■, sexes and young of. 11. 166.
Gakdm it, nil an . vample of r.ittonalUv In a
(n'/UMhnus, I. 824.

Oqrrvlm ykutdortm & 160*
<i iniM i:, 01 iterUltj of h\ brld plant*, 1
110.

40G

INDEX.

Gasteropoda, i. 315 ; pulmoniferous, court-
ship oC i. 816.

Gasterotitexui, L 200 ; nidifieation of; ii. 19.

G aster osteua leiurus, ii. 2, 14, 19.

Gaaterosteua trachurwt^ii. 2.

Gastrophora, wings of; brightly colored
beneath, i. 884.

Gauchos, want of humanity among the, i.

Gaudry, M., on a fossil monkey, 1. 189.
Garia, seasonal change of plumage in, ii.

Geese, clanging noise made bv, ii. 49 ; pair-
ing of different species of, ii. 109 ; Cana-
da, selection of mates by, ii. 112.

Gegenbaur, C, on the number of digits in
the Ichthyoptorygia, i. 120; on the her-
maphroditism of the remote progenitors
of the vertebrata, i. 199.

Gelasimm, use of the enlarged chela of the
male, i. 822; pugnacity of males of, L
828 ; proportions of the sexes in a spe-
cies of, i. 807 ; rational actions of a. i. 825 ;
difference of color in ^he sexes of a spe-
cies of, L 827.

Gemmules, sexual selection of, i. 297.

Genesis, i. 810.

Genius, ii. 812 ; hereditary, i. 106.
Genius, fertility of men and women of, i.
165.

Geoftboy Saint - Hilaire, Isid., on the
recognition of women by male quadru-
mana, i. 13 ; on the occurrence of a rudi-
mentary tail in man, i. 28 ; on monstrosi-
ties, i. 108 ; on animal-like anomalies in
the human structure, i. 120 ; on the cor-
relation of monstrosities, 1. 125; on the
distribution of hair in man and monkeys,

i. 148; on the caudal vertebras of mon-
keys, i. 144 ; on correlated variability. L
146 ; on the classification of man, i. 179 ;
on the long hair on the heads of species
of SemnopithtiCtis, L 184 ; on the hair in
monkeys, L 186; on the development of
horns in female deer, ii. 233; and F. Cu-
vier, on the mandrill, ii. 278; on Hylo-
bates, ii. 803, 805.

Geographical distribution, as evidence of

specific distinctions in man, i. 210.
Geometry, brightly colored beneath, i. 385.
Geopfiagus, frontal protuberance of male,

ii. 18, 20 ; eggs hatched by the male, in
the mouth or branchial cavity, ii. 192.

Georgia, change of color in Germans set-
tled in, i. 287.

Geotrupes, stridulation of, 1. 869, 870.

Gerbe, M., on the nest-building of Crenila-
brus massa and C. m^lops, ii. 19.

Gerland, Dr., on the prevalence of infanti-
cide, i. 90 ; ii. 828. 848 ; on the extinction
of races, i. 228 229.

Geevais, P., on the hairiness of the gorilla,
L 148 ; on the mandrill ii. 278.

Gesture-language, 1. 224.

Ghost-moth, sexual difference of color in
the, 1. 886, 890.

Gibb, Sir D., on differences of the voice in
different races of men, ii. 315.

Gibbon, IToolock, nose of, i. 184.
Gibbons, voice of, ii. 268.
Giraffe, mute, except in the rutting sea-
son, ii. 261 ; its mode of using the horns,

ii. 289.

Giraud - Teulon, on the cause of short

sight, i. 114.
Glanders, communicable between man

and the lower animals, i. 11.
Glands, odoriferous, in mammals, ii. 206,

267.

Glareola, double moult in, ii. 77.

Glrrmeria Hmbata, difference of color in
the sexes of, i. 331.

Glowworm, female, apterous, i. 247 ; lumi-
nosity of the, i. 335.

Gnats, dances of, i. 839.

Gnu, sexual differences in the color of the,
ii. 275.

Goat, male, wild, falling oh his horns, ii.
23s ; male, odor emitted by. ii. 266; male,
wild, crest of the, ii. 268; Berbura, mane,
dewlap, etc., of the male, ii. 271 ; Kemas,
sexual difference in the color of the, ii.
275.

Goats, sexual differences in the horns of;

i. 274; horns of; i. 280, ii. 285; domestic,
sexual differences of, late developed, i.
293 ; beards of, ii. 269 ; mode of fighting
of, ii. 238, 239.

Goatsucker, Virginian, pairing of the, ii.
47.

Gobies, nidification of, ii. 19.
God, want of the idea of, in some races of
men, i. 62.

Godron, M., on variability, i. 108; on dif-
ference of stature, L 111 ; on the want of
connection between climate and the color
of the skin, L 232; on the odor of tho
skin, i. 239; on the color of infants, ii.
803.

Goldfinch, ii 58, 79; proportion of the
sexes in the, i. 298; sexual differences of
the beak in the, ii. 87 ; courtship of the,

ii. 91.

Goldfinch, North American, young of, ii.
207.

Gold-Fish, ii. 16.

Gomphus, proportions of the sexes in, i.
816; difference in the sexes of, i. 351.

Gonepteryx Bhamni. i. 880 ; sexual differ-
ence of color in, i. 896.

G00D8IR, Prof., on the affinity of the lance-
let to the ascidians, i. 196.

Goosander, young of, ii. 181.

Goose, Antarctic, colors of the, ii. 218.

Goose, Canada, pairing with a Bernicle
gander, ii. 109.

Goose, Chinese, knob on the beak of the,
ii. 124.

Goose, Egyptian, ii. 44.

Goose, Sevastopol, plumage of, ii. 69.

Goose, Snow-, whiteness of the, ii. 218.

Goose, Spur-winged, Ii. 44.

Gorilla, ii. 808; eemi-erect attitude of
the, i. 187; mastoid processes of the, i.
188, direction of the hair on the arms of
the, i. 185; supposed evolution of the, i

IXDEX.

407

222; polygamy of the, i. 258, ii. 345, 346;
voice of the, ii. 262 ; cranium of, ii. 303 ;
fighting of male, ii. 309.

Gobse, P. H., on the pugnacity of the male
Humming-birds, ii. 38.

G08SE, M., on the inheritance of artificial
modifications of the skull, it 364.

Gould, B. A., on variation in the length of
the legs in man, i. 104 ; measurements of
American soldiers, i. 110, 112 ; on the pro-
portions of the body and capacity of the
lungs in different races of men, i. 208 ; on
the inferior vitality of mulattoes, i.
213.

Gould, J., on the arrival of male snipes be-
fore the females, i. 251 ; on the numerical
proportion of the sexes in birds, i. 29" ;
on Neomorpha, ii. 37 ; on the species of
EwtepKanm, ii. 37; on the Australian
Musk-duck, ii. 37; on the relative size of
the sexes in Biziura lobata and C'inclo-
ramphus cruralis, ii. 41 ; on Lobivanel-
Iw lobatus, ii. 46 ; on the habits of Me-
nura Alberli, ii 53; on the rarity of
song in brilliant birds, ii. 55 ; on Selaz-
phorun platycercw), ii. 62; on the Bow-
er-birds, ii. 66, 9S; on the ornamental
plumage of the Humming-birds, ii. 75 ;
on the moulting of the ptarmigan, ii. 79 ;
on the display of plumage by the male
Humming-birds, ii. 82; on the shyness
of adorned male birds, ii. 93 ; on the dec-
oration of the bowers of Bower-birds, ii.
107 ; on the decoration of their nests by
Humming-birds, ii. 107; on variation in
the genus Cynanthus, ii. 121 ; on the col-
or of the thighs in a male parakeet, ii.
121 ; on UroHticte Bengarnini, ii. 145,
146 ; on the nidification of the Orioles, ii.
160; on obscurely-colored birds building
concealed nests, ii. 161 ; on Trogons and
Kingfishers, ii. 165; on Australian par-
rots, ii. 166; on Australian pigeons, ii.
167 ; on the moulting of the ptarmigan,
ii. 173; on the immature plumage of
birds, ii. 178 et seq. ; on tho Australian
species of Tumix, ii. 192 ; on the young
of Aithurm polytmwt, ii. 211 ; on tho
colors of tho bills of Toucans, ii. 217 ; on
the relative sizo of the sexes in the Mar-
supials of Australia, ii. 248; on the colors
of the Marsupials, ii. 272.

Gourkau, on the stridulation of Mutilla
Europied, i. 355.

Gout, sexually transmitted, i. 283.

Graha, on tho Pied Ravens of the Feroe
Islands, ii. 121 ; on the Bridled Guille-
mot, il. 122.

Gradation of secondary se xual characters
in birds, li. 129.

Gkai.i.atokkh, absence of secondary sexu-
al characters In, i. 261 ; double moult in
some, li. 77.

Grallina, nidification of, IL 161.

Grahhiioi'I'Krs, stridulation of the, L 816.

GlATXOLET, Trot'., on the anthropomor-
phous apes, 1. 189; on the evolution of
the anthropomorphous apes, i. 227.

Gray, Asa, on the gradation of speciea
among the Composite, i. 219.

Gray, J. E., on the caudal vertebrae of
monkeys, i. 145 ; on the presence of ru-
diments of horns in the female of Cervu-
lus moschatm, ii. 234; on the horns of
goats and sheep, ii. 235 ; on the beard of
the Ibex, ii. 269; on the Berbura goat,
ii. 271 ; on sexual differences in the col-
oration of Rodents, ii. 272 ; on the colors
of the Elands, ii. 274 ; on the Sing-sing
antelope, ii. 275; on the colors of goats,
ii. 276; on the Hog-deer, ii. 289.

" Greatest happiness principle," i. 93, 94.

Greeks, ancient, i. 171.

Green, A. EL, on beavers fighting, ii. 223 ;
on the voice of the beaver, ii. 263.

Greenfinch, selected by a female canary,
ii. 110.

Greg, W. E., on the early marriages of
the poor, i. 167 ; on the ancient Greeks,

i. 171 ; on the effects of natural selection
on civilized nations, i. 161.

Grenadiers, Prussian, i. 103.

Grey, Sir G., on female infanticide in Aus-
tralia, ii. 343.

Greyhounds, numerical proportion of the
6exes in, i. 255, 256 ; numerical propor-
tion of male and female births in, i.
294.

Grouse, red, monogamous, i. 261 ; pugna-
city of young male, ii. 46 ; producing a
sound by scraping their wings upon
the ground, ii. 59 ; duration of courtship
of, ii. 96 ; colors and nidification of, ii.
163.

Grube, Dr., on the occurrence of the su-
pra-condyloid foramen in the humerus
of man, i. 27.

Grus Amerimnu.% age of mature plumage
in, ii. 204; breeding in immature plu-
mage, ii. 205.

Gtuh virgo, trachea of, ii. 57.

Gryllus eampeatris, i. 343 ; pugnacity of
male, i. 349.

Gryllus domestic™*, i. 343.

Grypus, sexual differences in the beak in,

ii. 37.

Guanacoes, battles of, ii. 228; canino

teeth of, ii. 246.
Guanas, strife for women among the, ii.

809; polyandry among the, ii. :tl'.t.
Guanchk skeletons, occurrence of tho

supra-eondyloid foramen in the humerus

of; i. 28.

Guaranys, proportion of men and women
among, i. 292; color of new-born children
of the, ii. 303; beards of the, ii. 3(17.

Guen£k, A., on tho sexes of I/yjun/thnt,
1.301.

Gt ii.DiNC, L.. on the stridulation of tho

L<M'ii#ti</<r, L MS.
Giiii.i.f.mot, variety of the, ii. 122.
<ii ink A, sheep ot; with males only horned,

1. 280.

Guinea-fowl, monogamous. I. 361 ; occa-
sional polygamy of the, i. 261 ; nuirKlugs
of the, 11. 129.

408

INDEX.

Guinea-pigs, inheritance of the efforts of
operations by, ii. 8(>8.

Gitll, instance of reasoning in a, ii. 104.

Gulls, seasonal change of plumage in, ii.
218; white, ii. 218.

GCntuer, Dr., on hermaphroditism in
{terra n us, i. '200 ; (in male Ashes hatch-
ing ova in their mouths, i. 201, ii. 10 ; on
mistaking infertile female fishes for
males, i. 29S ; on the prehensile organs
of male Plagiostomous fishes, ii. 2 ; on
the pugnacity of the male salmon and
trout, ii. 8 ; on the relative size of the
sexes in fishes, ii. 7; on sexual differ-
ences in fishes, ii. 8 et seqq. ; on the ge-
nus CaHionymus, 11.9; a protective re-
semblance in a Pipe-fish, ii. 18 ; on the
genus Solenostoma, ii. 21; on Mega-
lophrys montana, ii. 25; on the colora-
tion of frogs and toads, ii. 25 ; on sexual
differences in the Ophidia, ii. 72; on dif-
ferences of the sexes of lizards, ii. 30 et
seqq.

Oytianisa I*/'*, oeollated spots of. ii. 127.
Gypsies, uniformity of, in various parts of
the world, i. 288.

II.

IlAnrrs, bad. facilitated by familiarity, i.
97 ; variability of the force of, i. 176.

Hackel, V... on the origin of man, i. 4;
on rudimentary characters, i. 17 ; on the
canine teeth in man, i. 121 ; on death
caused by inflammation of the vermi-
form appendage, L 27 ; on the steps by
which man became a biped, i. 136; on
man as a member of the Catarrhine
group, i. 191 ; on the position of the Le-
murida?, i. 194; on the genealogy of the
Mammalia, i. 195; on the lancclct, i. 196;
on the transparency of pelagic animals,
i. 814; on the musical powers of women,
Ii. 821.

Hagen, II., and Walsh. B. Dn on Ameri-
can neuroptera, i. 806.

1 1 \ 1 1 :. development of, in man, 1. 24 ; char-
acter of, supposed to be determined by
light and beat, 1. Ill; tribution of, in
man, i. 144, ii. 859 ; jK>ssibly removed for
ornamental purposes, 1. 148; arrange-
ment and direction of, 1. 1$5 ; of the ear-
ly progenitors of man, i. 198; different
texture of, in distinct races, ii 208 ; ana
skin, correlation of color of, i. 288 ; de-
velopmeiit of. in mammals, ii. 2ii>; man-
agement ot, among different peoples, ii.
824; great length oC in some North
American tribes, iL 881; elongation of
the, on the human head, IL 865.

Hairiness, difference «»f hi the sexes in
man, IL 805; variation of, in races of
men, ii. 806.

Hairs and excretory pores, numerical re-
lation of, in sheep, i. 289.

IIaiky family, Siamese, ii. 861.

11 amadryas baboon, turning over stones,
L 72 ; mane of the male, IL 255.

Hamilton, C, on the cruelty of the Kaf-
fres to animals, i. 91 ; on the engross-
ment of the women by the Katfre chluik,
ii. 8.V2.

Hammering, difficulty of, 1, 133.

Hancock, A., on the colors of the nudi-
branch mollusca, 1. 817.

Hands, larger at birth, in the children of
laborers, i. 118; structure of. in the quad-
ra uiana, L 184; and arms, freedom of in-
directly correlated with diminution of
canines, i. 188.

Handwriting, inherited, i. 56.

Uarcocrt, E. Vernon, on FringiUa can-
nabina, ii. 82.

HareUla glaciali*, ii. 117.

Hare, protective coloring of the, U. 2S4.

Hares, battles of male, £ 996. •

Harlan, Dr., on the difference between
field and house slaves, 1. 287.

Hakims. .1. M., on the relation of com-
plexion to climate, i. 28(5.

Harris, T. W., on the Katy-did locust, I.
842; on the stridulation of the grass-
hoppers, i. :>4t'.: on </:'< iiiitliux ninifi*, i.
860; on the coloring of I^pidoptera, 1.
INtKin the coloring of ,W ///•///</ /„. i.

Harry-long-leus, pugnacity of malts L
889.

Hart man. Dr., on the singing of Cicada
mi /iti -in fere hi. i. 840.

Hauqhton, S., on a variation of the flexor
jiollicis longus in man, i. 124.

Hawks, feeding orphan nestling, ii. 103.

Hayes, Dr., on the diverging of sledge-
dogs on thin ice, i. 45.

Head, altered position of. to suit the erect
attitude of man, i. 138 ; hairiness ot
in man. i. 142; processes of, in male
Indies, i. 857; artificial alterations of the
form of the, ii. 835.

Hearne, on strife for women among the
North American Indians, ii. 80S; on the
North American Indians1 notion of fe-
male beauty, II. 828; repeated elope-
ments of a North American woman, ii.
B66.

Heart, in the human embryo. L 16.
Heat, supposed effects of, i. 111.
HectiH-tttijte. i. 816.

Hkim;k-wai:iu.kk, ii. voting of the, ii.
200.

Heel, small projection of, in the Aymara

Indians, i. 115.
Hegt, M«, on the development of the spurs

in peacocks, i. 9BL
Hklk omh.k i. '■>'•>: mimicry of, by other

butterflies, i. 898.
Heliopathe*. stridulation peculiar to the

male. I. 871.
Iltliothriw aurlculata. voim- of. ii. 1^0

181.

//»■//> pomatia, example of Individual at-
tachment in. L 816.

Hellins. J- i»roi»ortions of sexes of Lepl-
doptere reared by, 1. 804.

Helmiioltz, on the vibration of the audi-
tory hairs of Crustacea, ii. 817.

INDEX.

409

Hemiptera, i. 839.

Ilemitragm, beardless in both sexes, ii.
269.

Hepburn, Mr., on the autumn-song of the

w ater-ouzel, ii. 51.
Hepialm humuli, sexual difference of

color in the, i. 386, 390.
Herbs, poisonous, avoided by animals, i.

36.

II erma piiroditism of embryos, i. 199.

Herod 'uiH bubulcuH, vernal moult of, ii. 80.

Heron, love-gestures of a, ii. 65.

Her< >n, Sir E., on the habits of peafowl, ii.
115, 116, 146.

Herons, decomposed feathers in, ii. 70;
breeding-plumage of, ii. 78, 79; young
of the, ii. 200; sometimes dimorphic, h.
205; continued growth of crest and
plumes in the males of 6ome, ii. 206 ;
change of color in some, ii. 221.

Iletcerina, difference in the sexes of, i.
351 ; proportion of the sexes in. i. 306.

Ifeterocerus, stridulation of, i. 368.

Hewitt, Mr., on a game-cock killing a
kite, ii. 41; on the recognition of dogs
and cats by ducks, ii. 106; on the pairing
of a wild-duck with a pintail drake, ii.
110; on the courtship of fowls, ii. 112;
on the coupling of pheasants with com-
mon hens, ii. 117.

Hindoo, his horror of breaking his caste,

i. 95, 98.

Hindoos, local difference of stature among,
L 111; difference of, from Europeans, i.
231 ; color of the beard in, ii. 804.

Uipparctiia Janira, instability of the
ocellated spots of, ii 127.

IRpparctdm, i. 375.

Hippocampus, development of, 1. 202;
marsupial receptacles of the male, ii. 20.

Hippopotamus, nakedness of, i. 142.

Hips, proportions of, in soldiers and sail-
ors, 1. 112.

IIojx.kon, 8., on the sense of duty, 1. 68.
Hokkhkro, on the horns of the reindeer,

ii. 288; on sexual preferences shown by
reindeer, ii. 260.

Hoo, wart, U. 258; river, ii. 254.
Hoo-dkku, ii. 289.

Holland, Hlr 11., on the effects of new
diseases, L 280.

HOMOLOOODI structures, correlated varia-
tion Of, 1. 125.

IIomoitkka, 1. 840; stridulation of the,
and orthoptcra, discussed, i. 349.

IloNDi iiAs, QuUoahis major in. I. 298.

Hombt-bcxzabo of India, variation in the
craft of, II. 121.

Ho.nev-ki cKKits, moulting of the, U. 79;
Australian, nldlflcatlou of, Ii. 161.

Hosoit, law of, I. 95.

UooKCB, Jot., on the color of the beard In

until, II. 804
HOO LOOK (iiniiMN, DOM i>f, I. 184
Hoo FOB. II. 58; loundj produced by the

mab', II. 80.
Boptopt4tut armatu«, wring spun of, II.

Hornbiul, African, inflation of the neck-
wattle of the male during courtship, ii.
69.

Hornbllls, sexual difference in the color
of the eyes in, ii. 123; nidification and
incubation of, ii. 161.

Horne, C, on the rejection of a brightly-
colored locust by lizards and birds, i. 351.

Horns, of deer, ii. 232, 287, 248; and canine
teeth, inverse development of, ii. 245
sexual differences of, in sheep and goats,
i. 273 ; less of, in female merino sheep, i
275; development of, in deer, i. 278; de-
velopment of; in antelopes, i. 280; from
the head and thorax, in male beetles, i.
357.

House, polygamous, i. 258 ; canine teeth of
male, ii. 280; winter change of the, ii.
284; fossil, extinction of the, in South
America, i. 231.

Horses, dreaming, i. 44; rapid increase of,
in South America, i. 130; diminution of
canine teeth in, i. 138; of the Falkland
Islands and pampas, i. 227; numerical
proportion of the sexes in, i. 255, 256;
lighter in winter in Siberia, i. 273; sexual

1 (references in, ii. 260; pairing preferent-
y with those of the same color, ii. 281 ;
numerical proportion of male and female
births in, i. 293; formerly striped, ii. 291.
Hottentot women, peculiarities of, i. 217.
Hottentots, lice of, i. 212; readily become
musicians, ii. 318; notions of female
beauty of the, ii. 829; compression of
nose by, ii. 335.
House-slaves, difference of, from field-
slaves, 1. 237.
Hubkr, P., on ants playing together, 1. 3S;
on memory in ants, i. 44; on the inter-
communication of ants. i. 56 ; on the rec-
ognition of each other by ants alter sepa-
ration, i. 804
Hue, on Chinese opinions of the appear-
ance of Europeans, ii. 82s.
HUXAJI kingdom, i. 179.
lh'MAN sacrifices, I. 66.
Hi'manity, unknown among some sav-
ages, I. 91 ; deficiency of, among savaircs,

i. 97.

Hi miioldt, A. von, on the rationality of
mules, i. 17 ; on a parrot praam ing the
language of a lost tribe, i. 22S; on the
cosmetic arts of savages, ii. :!•_' t ; on inn
exaggeration of natural characters b\
man. II. BBtj on the red painting of
American Indians, ii. B8&

Hi MB, !>., on sympathetic Bmltn.fl, i. s|.

Ill MMiMi-iiiito", racket shaped tenth, is in
the tail of a. ii. 7o; display of phuiagt]
by the mule. ii. St.

Hi \i \i i sr. in it i>s, ornament tin ir in s|s, |.

cm. ii. inT; polygainoua, L MO: propor-
tion of the sexes in. I. 29H, II. 218; coal

diflerenooa in. U. :it. 88, 1 10; pugnacity
of male, ii. us; roodlflod prtmarki of

male, II. 62; coloration of tb.' im-xch of

ii. TB ; young or, ii. -.mi ; nldlnoatkta of
the II. 100; color* ei' i, mule, II. I no

110

INDKX.

Hi

m, II. N, on the hablta of tlio
Btlokle-lwek, L Ml, iL i.
Hung kk. Instinct of, L 80.
HrNK, ancient, flattening of the noso by

the. iL 825.
Hunter, J., on the number of species of
man, L 218; on secondary sexual charac-
ters, 1. 243 ; on the general behavior of
female animals during courtship, 1. 264;
on the muscles of the larynx In song-
birds, 11. 52 ; on the curled frontal hair of
the Bull, iL 269 ; on the rejection of uu
a*> by a female zebra, ii. 2M.
Hunter, W. Wn oo the recent rapid in-
crease of the San tall, L 123; on the San-
tali, L 282.

Huhset, Mr., on a partridge distinguishing
(tenons, U. 105.

Hi t< iiinson. Colonel, example of r. zon-
ing In a retriever, L 46.

Hi n«.v. Captain, on the male wild-goat
Hilling on his horns, 11. 288.

Huxley, T. H., on the structural agree-
ment of man with the apes, L 8; on the
agreement of the bruin in man with that
of lower animals, i. 10; on the adult ago
of the Orang. 1. 18; on the embryonic de-
velopment of man, 1. 14; on the origin
of man, L 4, 17 ; on variation m the skulls
of the natives of Australia, i. 104; on the
attductor of the fifth metatarsal in apes,
L 128; on the position of man, 1. 138; on
the sub-orders of primates, 1. 1ST ; on the
Lemurida?, L 194; on the Dinosauaria, L
196; on the amphibian affinities of the
Ichthyoaaurians, L 190; ou variability of
the skull in certain races of man, L 818;
on the races of man. i. 219.

Ilviiam birds, production of, ii. 109.

Hydrophobia communicable between man
and the lower animals, L 11.

Hydroporv*, dimorphism of females of,
1 888.

Hjftlaphm pot

J/i/Urogot, m*. il. tti.

/////</. singing spe, i-s of. ii.

J/,//.,'„itrA, mat- mal affection in a. i. 89;
absence of the thumb in, i. 18..; upright
progression of some species of L 187;
direction of the hair on the anna of spo-

of, i. 1*5; musical voice of the. iL 264;
superciliary ridge of, IL 808; voice of, IL
811

HylobaUt Woo*, sexual difference of

color in. IL "ill.
IIylo>*iU* fcir, L 185; hair on the arms of,

L185.

HvhJ„itt* ItucitruK i. 1XV

IhjUtbiitt* m/tuliutylut, L 186; laryngeal

sac of. II. J'.l.

11 TVEXumiA, L 858 ; large size of the cer-
ebral iranglia in. I. 1*»: claaslflcatlon of.

IlYMI

I'-""

seden-

II. 2S0.

Ihnnnum-hu* aqmiUcut, 11.288.
J/yju-ryUtra, proi»ortion of the sexes In, L

801.

Ilypogymna di*par, sexual difference of

color In, I. 8s6.
J/i/jmjii/ru, coloration of. i. 8-»l.

I

Iiikx. male, falling on his horns, ii. 28$;

beard of the, iL 269.
Ibis, scarlet, young of the, II. 199; white,

change of color of nak< d skin in, during

the l.reediiig-M-a.x-.n. ii. '>'<■
Ibi* tanUilu*. age of mature plumage In. II.

2D4; breeding in immature j.ltimage, ii.

906,808.

Imms decomposed fathers In, II. 71;

white, IL 21s, and black, iL 280.

I( IIM-.I UoMD.K, illlh I-. nee of the sc.XcS In,

L 854.

I< 1 1 T 1 1 Y • iITFJnY'i 1 \. 120.

IniTUTOflAcaiANa. iL 196.
Ideas, general, L GO.

Idiots. mi. roc. phaloiis. Imitative facultlea
of. i..V>: microcephalous, their characters

and habits, 1. 118.
/;/'/<;//./ tuhi rcttiata, ii. 81.

IliUANAA, 11. 80.

Illegitimate and legitimate children, pro-
] tort ion of the sexes in, L 292.

Imagination, existence ot, to animals. 1. 44.

Imitation. I. 8»; of man by monkeys, L
l.': t. inlciic-y to, in monkeys, microce-
phalous Idiots and savages, L 55; in-
fluence of 1. 155.

I mm att* ee plumage of birds, 11. 175, 179.

I MPLACENTATA, L 194.

Implement*, employed by monkeys, I. 49;

fashioning oC peculiar to man, L 51.
Ivi uii.N vtiov, jK-riod of, influence of, up-

POS4

1n<

t\ man alone snp-

.48.

out or flk-d by

Incrrase, rate of, L 186; noceasity of

checks in, L 180.
Indecency, hatred of, a modem virtue, L

India, difficulty of distinguishing the na-
tive nice, ot; i joT; Cvprinida. oC 11. 17;
color of the beard in races of men of, iL

804.

Indian, North American, honon-d for scalp,
tog a man of another tribe, L 90.

ALITY, L 60.

'ATION, L 810.

14 caHoUu. colors of the scj

M of.

Inpanticids, prevalence of, L 90, 120 ; sup-
posed cause ot Ii. 82s; prevalence and
causes of, IL 847, et —q.

Inpeeioeity, supposed physical, of man, I

160. •

INDEX.

411

Inflammation of the bowels, occurrence
of, in C'ebu# Azaroe, i. 12.

Inheritance, L 106; of effects of use of
vocal and mental organs, i. 56; of moral
tendencies, i. 98, 100; of Ion? and short
sight, i. 114; laws of, i. 270; sexual, i.
276; sexually limited, ii. 147.

Inquisition, influence of the, i. 172. ■

Insanity, hereditary, i. 107.

Insect, fossil, from the Devonian, i. 349.

Inskctivoea, ii. 272 ; absence of secondary
sexual characters in, i. 259.

Insects, relative size of the cerebral gan-
glia in, i. 139 ; male, appearance of, before
the females, L 252; pursuit of female, by
the males, 1. 263; period of development
of sexual characters in, i. 282 ; secondary
sexual characters of, i. 331 ; stridulation
of, ii. 315.

Insessoees, vocal organs of, ii. 52.

Instep, depth of, in soldiers and sailors, i.
112.

Instinct and intelligence, L 86.

Instinct, migTatory, vanquishing the ma-
ternal, i. 80, 81.

Instinctive actions, the result of Inheri-
tance, 1. 77.

Instinctive impulses, difference of the
force o£ L 83, 85; and moral impulses,
alliance of, i. 84.

Inbtincts, i. 35; complex origin of through
natural selection, L 37 ; potable origin of
Borne, L 37; Matured, of domestic animals,
L 76; variability of the force of, i. 79; dif-
ference of forc« between the social and
other, i. 85, 99 ; utilized for now purposes,
11.819.

Instrumental music of birds, II. 59, 64.
Intellect, hlflnenoe of, in natural .selection

in civilized soc iety, L 164.
Intellectual faculties, their Influence on

natural selection In man. L 152; probably

perfected through natural selection, i.

154.

Intelligence, Mr. II. Spencer on the dawn
of, L »6.

Intemperance, no reproach among sav-
ages, I. 92; Its dcstructlvcncss, I. 168,

Intoxication In monkeys, I. \ >.

Jjiltiu* ylmtvlppe, i. 3M.

litis, mcxiiuI difference In the color of tin.
In birds, II. 09, 196.

leoMttwoBio araeele, 1. 122.

UIiiI{/IhU oruentiiM, Dumber <.r spurn In, II.
41

Julun, tarsal suckers of the males of, |. :fc»0.

Ja< kai.m learning to bark from dogs, |
Ja< 'K-hnii'e, coloration of the, II „'|6.
jAigi ixoT, on the number of hpeclcn of

man, I. 21 H.
JakoKh, Dr., on the difficulty of approach

Ing berdaof erlld enbnala, i 71 , on the
ln<T»ii»». of l«njth In bon< », 1 II.'; on th<>

deposition of a male Silver-pheasant on

account of a spoiled plumage, ii. 115.
Jag CAEs, black, ii. 280.
Janson, E. W., on the proportions of the

sexes in Tomicux till onus, L 305; on

stridulant beetles, i. 367.
Japan, encouragement of licentiousness

in, 1. 129.

Japanese, general beardlessness of the. ii.

306; aversion of the, to whiskers, ii. 892.
Jardine, Sir W- on the Argus pheasant,

ii. 69, 93.

Jarrold, Dr., on modifications of the
6kull induced by unnatural position, i.
141.

Javanese, relative height of the sexes of,
ii. 305; notions of female beauty, ii. 331.

Jaw, influence of the muscles of the. upon
the physiognomy of the apes, i. 13S.

Jaws, smaller in "the same ratio with tho
extremities, i. 113; influence of food
upon the size of, i. 113; diminution of. in
man, i. 138; in man, reduced by correla-
tion, ii. 309.

Jay, young of the, ii. 200; Canada, voting
of the, ii. 200.

Jays, new mates found by, ii. 100; dis-
tinguishing persons, ii. 105.

Jeffreys, .J. Gwyn, on the form of the
shell in the sexes of the (Gasteropoda, i.
815; on the influence of light upon the
colors of shells. 1. 317.

Jelly-fish, bright colors of some, I. 318.

Jenner, Dr.. on the voice of the r.x.k. ii.
5*; on tile finding of new mates by mag-
pics, ii. 99; on retardation of the genera-
tive organs in birds, ii. Kef.

Jknv.ss, I... on the desertion of their young
by swallows, i. ISO; on male Midi sing-
ing aflor the proper season, ii. 103.

Jeriion, Dr.. on birds dreaming. 1. 44; on
the pugnacity of the male blllbul, ii. .".'.t ;
on tlie pugnacity of the male ( hti/yurn it
(/ii/hHm, ii. 42;*ou the hours of i, ,,//,,-
peril is, ii. 41 ; on the habits of l.<<!>ir.i
in Hum, ii. 46; on the h|Ktonblll, ii. 57 ; on
the drumming of the Kail} -pheasant Ii
GO; on Indian bustards, ii. »._>; on oti»
lienqnl, hmIh, 11.66; on the ear-tufts of
Si/ j limit ill en (inritiiM, ii. 70; on the
double moults of certain birds, il. 7'.' ; on

the moiiltin- ,.f UM I v-Mi. k. i s, ii T'.i ;

on the moulting of huM.n d*. ploTOIl siid

dronfoa, ii- v"; on dtopjay in male bfcda,

II. h'£\ on the spring change of color In

Some till, lies, II. M ; Oil the Olaplaj of

the under tall ...\. it* b> the m.ile'blll-

bnl ii.t'i; on tin- Indian bona] bnjanwdi

U. 121 ; on mxutil (linen tie. « In the r >k>r
of the i yes of horilbllk Ii. IS I ; o.i the
nun-king* "t th" 1 1 ugopan |.|m isint. u
I2S; on the iildlllcaHoii of the Ohok * H.
180 ; on (be ni. liiic.iti. >n of Hie bm DbiUa,
II 161 I ..ti UM Milt. hi \. Ikm tit. II 167 ;
on /'.//.r.T'iM ,l,n .in i- UM, l| IT.1, ..ii Hid
immiitiiii. |.lumngi< of bud* II I7\ isf

,• oil rvprc*cUf»ll\« »|H,le* ..[ 1

II I*.' , mi the habit* of /W/n>, II.

I '.'.I,

412

INDEX.

on the continued Increase of beauty of
the p«acock. ii. 'Ji'T; on coloration In
the genus I'ahrorni*, II. 2*21.
Jevons, W. S., on the migrations of man,
1. 180.

Jews, ancient use of (lint tools by the, i.
176; uniformity of, in various parts of
the world, 1.233; numerical i>ro|M>rtion
of male and female births among the. I.
'21* 1 ; ancient tattooing practised by, IL
823.

Johnstone, Lieutenant, on the Indian ele-
phant, i. 259.

Joli.ofh, Hue appearance of the, H. 841.
Jones, Albert, proportion of sexes of Le-

pidoptera, reared by, i. 8(4.
Juan Fernandez, humming-birds of, II.

212.

Jiinoniii. sexual differences of coloring in

species of, I. 877.
Jl l'iTER, timet statues of. IL 833.

K.

Kaffre skull, occurrence of the diastema
in a, L 121.

K un:i\ their cruelty to animals, i. 90;
lice of the, L218; color of the, iL 880;
engrossment of the handsomest women
by the chiefs of the, ii. .'!.".•_'; murriage-
customs of the, ii. 357.

K ALiJ-cjiK as a nt. drumming of the male,
11. 59; young of, U. 182.

Ktiltiina, resemblance of to a withered
w leaf i. :W>.

Kangaroo, great ml, sexual difference In
the color of, iL 278.

Kant, Iiimiamiel, on duty. i. 07 ; on self-
restraint, I. NJ; on tho number of sjh-cIcs
of man, L 218.

KatT-DID, >t rid illation of the, i. 842.

Keller, Dr.. on the dimculty of fashioning
stone implements, L 188.

Kk-.ti-.ki h, new mates found bv. 11. loo.

Kit-net. i. 112.

Kino, W. R., on the vocal organs of Tetrao
cupido, iL 55; on the drumming of
grouse, ii. 60; on the reindeer, iL 288;
on the attraction of male deer by the
^ voice of the female, 11. 268.

Kino and Fltxroy, on the marriage-cus-
toms of the Kuartans, IL 857.

Kino-cbows, nldlfatton of, 11. 160.

Kino run kr, 11. 58; racket-shaped feathers
in the tail of a, IL 70.

KiNonSHERS, colors and nldlflcat Ion of the,
11. 168, 165, 16^; immature plumage of
the, ii. INI, lv.>; young of the. II. 2<Ht.

KiNii I/'RV. ii. ltV>; IliiliiatUP' plumage

of the, iL 190.
Kings let, C, on the sounds produced by

Kxbbt and Spencc. on the courtship of in-
sects, 1. 248: on sexual differences In the
length of the snout In curcultonidii-. 1.
247 ; on the elytra of DytUctu, 1.888 ; on
pot uharities In the legs of male insects, L

884; on the relative size of the sexes In bi-
sects, 1.885; on the luminosity of insects,

I. 835; on the Kulgoridie, L 840; on tho
habits of 7, rmitt*. i. 353 ; 011 difference
of color in the seVeS of hectics, i. ilMi ; on
the horns of the male lumcllicorn beetles,
i. 859; on hornlike processes in rn.de
curcullonldn?, 1. 863; on the pugnacity
of the male stag-beetle. L 864.

Kite, killed by a game-cock. II. 42.

Knot, retention of winter plumage by the,

II. 78.

Kvox, R„ on the semilunar fold, I. 28; on
the occurrence of the supra -condyloid
foramen in the humerus of man, L'27;
on the features of the young Meninon, 1.

209.

Koala, length of the orcnm in, L 26.
KAlrecter, on the sterility of hybrid

plants. I. '215.
h'l'fm* tt/ij>fi/'ri/>/i»iix, j.rojH»rtion of the

sexes in. 1*296.
K ■". development of the horns of the,

i. •_'7'.»: markings of the. ii. '>7.
Kopprn, F. T., on the migratory locust, L

34*2.

Kobdofan. protuberances artiflclally pro-
duced in. 11. 3-28.

Kowai.kvskv. A„ on the affinity of tho
Ascidia to the Vertebrata, i. 197.

Kowauctsett, W, on the pugnacity of the
male Capercailzie, II. 4*2 ; on the pairing
of the Capercailzie, 11. 47.

Kbause, on a convoluted body at the ex-
tremity of the tail in a Macuriu and a
cat, i. '29.

Kuppfer. Prof, on the affinity of the As-
cidia to the Vertebrata, L 197.

Im

LahUloctra Ikirtrinii, prehensile organs

of the mnk\ I. 8*20.
ImItuh, splendid colors of the species of

IL15.

jAihriu fn ixtu*. sexual differences in, IL 9.
lAtbrus pa to, IL 15.

I.acertili a, sexual differences of 11. 80. ,
La ni ESN ate, M. de, on Minis of Paradise,

IL 78.

Lamabck, on the origin of man, 1. 4.

Lamellibbancuiata, I. 815.

Lamellicobn beetles, horn-like processes
from tho head and thorax of I. 857, 802;
analogy oC to Ruminants, L 861 ; iutlu-
ence of sexual selection on, I. 365.

I. sMi I 1 K mkma. stridulatioii of I.

Lamoxt, Mr., on the tusks of the Walrus,
II. '231 ; on the use of its tusks by the
Walrus, iL 245.

iAimporui* porjtfiyruni*, colors of the fe-
male. IL 160.

Lancbuct. L 196. 204.

Landois, IL on the production of sound
by the CVad*?, L 840; on the stridulating
organ of the Crickets, I. 844 ; on Dtcti-
cus, L 345; on the stridulating organ* of

INDEX.

413

the Acridiidae, i. 845 ; on the presence of
rudimentary stridulating organs in some
female Orthoptera, i. 348 ; on the Btridu-
lation of Necrophorus, i. 367 ; on the
stridulant organ of Cerambyx heros, i.
368; on the stridulating organs in the
Coleoptera, i. 370; on the ticking of
Anolkum, i. 373; on the stridulant or-
gan of Geotrupes, i. 369.

"Language an art,!. 53; articulate, origin
of, i. 54; relation of the progress of, to
the development of the brain, i. 55 ; ef-
fects of inheritance in production of, i.
56 ; complex structure of, among barbar-
ous nations, i. 59 ; natural selection in. i.
59; gesture, i. 224; primeval, i. 226; of
a lost tribe preserved by a parrot, i. 228.

Languages, presence of rudiments in, i.
58; classification of, 1.58; variability of,
i. 58 ; crossing or blending of, i. 53 ; com-
plexity of, no test of perfection or proof
of special creation, i. 60; resemblance of,
evidence of community of origin, i. 182.

Languages and species, identity of evi-
dence of their gradual development, i.
57,

Lanius, iL 172; characters of young, ii.
177.

jAinitut rufu*, anomalous young of ii. 202.

Lankkstkk, K. K., on comparative longev-
ity, i. 161, 164; on the destructive effects
of intemperance, i. 166.

Lanugo, of the human f<etus, i. 25; 11. 359.

Lapi'oman language, highly artificial i. 59.

Lakk, proportion of the sexes in the, i.
293; female, singing of the, ii. 51.

Larks, attracted by a mirror, ii. 107.

Lartkt, Ba, on the size of the brain in
mammals, 1. 49; comparison of cranial
capacities of skulls of recent and tertiary
mammals, 1. 140; on DryupitlivcuM, i.
191.

Ismm, seasonal chu?gc of plumage In, ii.
218.

Larva, luminous, of a Hrazillan beetle, i.
335.

Larynx, muscles of the, in song birds, ii.
52.

IsiHitx'amjHi niifri'iiM, attraction of males
* by tlm female, I. 303 ; sexual difference
of color In, L8M
Latham, It. (i, on the migrations of man,

I. IfL

Latooka, perforation of the lower Hp by
the Women of, II. 825.

Lai Kii.i.Ato, on the abnormal division of

the miilur DOM in man. I. 119.
Lawkkmi r„ W„ on the luporloritv of uv-
ajfen to Kiiropeatis In power 01 tight, I.
Ill; on the color or nc^ro Infants, II.
308; on the fondues* of suvatfci, tor or-
namunU, II. 322; on I., u.ll. s, ,•.„ ,. ,. n.

882; oil the Leant) of the KnKllsh ni ls-
l«NTucv, II. .til.

Layako. k. i.., on mi Umtaaea •>( rational
It v In ■» Oobra, ILW: on the pugnacity
i>( QalUu BttinUyU IL

UirmK, l»i , on \lt.J p. il,Ml|c|(y, I. 12.

Leaves, decaying, tints of, i. 314.

Lecky, Mr., on the sense of duty, i. 63 ; on
suicide, i. 90 ; on the practice of celibacy,
i. 92 ; his view of the crimes of savages,
i. 93; on the gradual rise of morality, i.
99.

Leconte, J. L., on the stridulant organ in
the Coprini and Dynastini, i. 369.

Lee, II., on the numerical proportion of
the sexes in the trout, i. 299.

Leg, calf of the, artificially modified, ii.
324.

Legitimate and illegitimate children, pro-
portion of the sexes in, i. 292.

Legs, variation of the length of the, in
man, i. 104; proportions of, in soldiers
and sailors, i. 112; fore-, atrophied in
some male butterflies, i. 334 ; peculiar-
ities of in male insects, i. 334.

" Lek " of the black-cock and capercailzie,
iL 96.

Lemoine, Albert, on the origin of language,

i. 54.

Lemur macaco, sexual difference of color
in, ii. 276.

Lemukid.k, i. 137; their origin, i. 204; po-
sition and derivation of the. i. 194; ears
of the, i. 22 ; variability of the muscles in
the, i. 123.

Lemurs, uterus in the, i. 118; tailless spe-
cies of, i. 137.

Leopards, black, ii. 280.

Lepidoptera, 1. 374; numerical projec-
tions of the sexes in the, i. 301 ; coloring
of, i. 375; occllated spots of, ii. 127.

LfjnO'fmren, i. 196, 204.

Lknguas, disfigurement of the ears of the,

ii. 325.

Le/)torfii/nrfiiia auguxtatiui, pugnacity of

male, i. MB,
Lejitura tmUUMf difference of color in the

sexes of i. 856.
Lkquay, on the occurrence of the suprn-

condyloid foramen in the humerus of

man, 1. 2S.

Lkkoy, on the wariness of ynung foves in
hunting-districts, i. Is; on the desertion
of their young bv swallows, 1. SO.

LkhxK, Valley of the, I. 'Js.

Lksh.iN, on' the llhds of Paradise, I. 'Jl'il I,
II. Mj on the sea-elephant, ii. MB.

l.»»ti* l">iiili,/l,i,iM, ditlcreneo of the sexes
In. I. 851.

Lrthru* ct/ihn/ofsM, pugnacity of th«

males <.r, I. MB, Mi.
Lkui kaht, It., on the rmieula pn**t>iHm,

I. 8(1; on the llltlllelice of the uge of j, n .

cuts on the sex of offspring, I 'J92.
ljratnr ././ riril/.r muscle, I I.':
I.ilirlluht oV;i/i7>/»</, co|,. i- of the male, I.

852.

I. Mil I I.I I ll> V, relutlv.i s|/c of the •<■ Xe« of

I .u; ; .tut. i . i,. . iii the s. x. , .,r. i 8.M.
i.i. i of d itk anlmaki and nan, i -.'it.

Lli'KNTIol hmj»k, liri'N illelice of, Mtiolu' -i\

ayes, I. I* J ; u chock upon population, I
I.i. iiicnsit.in, on < htm ;<r»v"«S H5-

Ill

INDEX.

Lift, Inheritance at corresponding periods
o', i. 271, 276.

Lhmit, supposed effects of, i. Ill; influ-
ence of, upon the colors of shells, i. 817.

Lilford, Lord. the ruff attracted hy bright
objects, ii. 107.

Limoaa lapponica, ii. 195.

Linaria, ii. 172.

Linoria montana, 1. 298.

Linn^cs, views of, as to the position of
man, i. 188.

Linnet, numerical proportion of the sex-
es in the, i. 298 ; crimson forehead and
breast of the, ii. 82 ; courtship of the, ii.

Lin j/pMa, i. 828.

Lion, polygamous, i. 259 ; mane of the, de-
fensive," ii. 264 ; roaring of the, ii. 262.

Lions, stripes of young, ii. 176.

Lips, piercing of the, by savages, ii. 825.

Lithooius, prehensile appendages of the
female, i. §30.

LithottUi, coloration In, i. 883.

Littorina tittorea, i. 815.

Livingstone, Dr., on the influence of
dampness and dryness on the color of
the skin, i. 288 ; on the liability of ne-
groes to tropical fevers after residence in
a cold climate, 1. 234; on the spur-
winged goose, ii. 44 ; on weaver-birds,
ii. 60; on an African night-jar, ii. 69, 92 ;
on the battle-scars of South African male
mammals, ii. 22S ; on the removal of the
upper incisors by the Batokas, ii. 824;
on the perforation of the upper lip bv
the Makalolo, ii. 826; on the Banyai, i'i.
827.

Livonia, numerical proportion of male and
female births in, L 292.

Lizards, relative size of the sexes of, ii. 30;
pillar pouches of, ii. 81.

Llotd, L-, on the polygamy of the caper-
cailzie and bustard, i. 261 ; on the numer-
ical pro[>ortion of the sexes in the caper-
cailzie and black-cock, i. 297 ; on the sal-
mon, ii. 5 ; on the colors of the sea-scor-
pion, ii. 9; on the pugnacity of male
grouse, ii. 42; on the capercailzie and
black-cock, ii. 47, 52 ; on the call of the
capercailzie, ii. 58; on assemblages of
grouse and snipes, ii. 97 ; on the pairing
of a shield-drake with a common duck,
ii. 109; on the battles of seals, iL 229; on
the elk, U. 288.

J.<ihir,i;i,!hiM, winp-spurs in. ii. l»">.

Local influences, effect of, ujwn stature, i.
110.

Ixx-KWtJon, Mr., on the development of

//iji/HH'ti/ti/ntJ). i. 201.
Loci -t. bright-colored, rejected bv lizards

and birds, i. 850.
Locust, migratory, i. 842.
I.-M i stio.f. stridiilation of the, i. 841, 313;

descent of the, L 846.
LoNoiooRN beetles, difference of the sexes

of, in color, L 856 ; stridulation of, L 868.
Lonsdale, Mr., on an example of personal

attachment in J/elijr pomatia, i. 816.

LopiionRANcmi, marsupial receptacles of
the male, ii. 20.

Lophophorutt, habits of, ii. 116.

Lojihorina atrn, sexual difference in color-
ation of, ii. 216.

Lophorni* ornatiui, ii. 78.

Lord, J. K., on Stilnio h/c/iotlon, 11. 5.

Lorv, Kinp. ii. 166; immature plumage of
the, ii. 180.

Love-antk s nml dances of birds, ii. 65.

Lowne, 1J. T., on Mitw<i eviuitoria, i. 140,
839.

Loxia, characters of young of, ii. 176.

LniHocK, Sir J., on -'the antiquity of man,
i, 8 ; on the origin of man, i. 4 ; on the
mental capacity of savages, L 88; on the
oripin of implements, i. 51 ; on the sim-
plification of languages, i. 60; on the ab-
sence of the ideaof (1<h1 anion;: certain
races of men, i. 63 ; on the origin of the
belief in spiritual agencies, i. 66; on su-
perstitions, i. 66; on the sense of duty, i.
68; on the practice of burying the old
and sick among the Fijians, i. 74 ; non-
prevalence of suicide among the lowest
barbarians, i. 90; on the immorality of
savages, i. 98 ; on Mr. Wallace's claim to
the origination of the idea of natural se-
lection, i. 182; on the absence of remorse
among savages, i. 15S ; on the former bar-
barism of civilized nations, i. 174; on im-
provements in the arts among savages, i.
175; on resemblances of the mental char-
acters in different races of men, i. 224 ; on
the power of counting in primeval man,
i. 2'J."> ; on the arts practised by savages,
i. 225; on the prehensile orpans of the
male Labitlocevn Ihtrirhiii, i. 320; on
Chloion^ i. 831 ; on Smynthurv* luteus,

i. 888; on strife for women anions the
North American Indians, ii. 80S; on mu-
sic, ii. 818; on the ornamental practices
of savages, ii. 322; on the estimation of
the beard among the Anglo-Saxons, IL
#13: on artificial deformation of the skull,

ii. 835; on "communal marriages,11 ii.
842. 344 ; on exogamy, ii. 844. 848; on the
Ve.l.lahs. ii. :U7: on polyandry, ii. 319.

Li • ami' k. variabilis of the mandibles in.

the male, i. 864.
LtwaniiM, large size of males of, i. 336.
LuvnnuM rt rri/M. numerical proportion of

sexes of, L 305 ; weajious of the male, i.

864.

I. a, -,i n >is , hi j J, ii.--. u-.,. of mandibles of, i.
865 ; large jaws of male. 1. 332.

I. rev. Prosper, on sexual preference in
horses and bulls, ii. 260.

Lunar periods, i. 204.

Lund, Dr., on Bkulls found in Brazilian
caves, i. 210.

I.i M.s. enlargement of. in the Qucebna and
Aymara Indians, i. 1 15 ; a modified swim-
bladder, L 198; different capacity of, in
races of man. i. '.'o^.

Luminosity In insects, 1. 835.

I.i -« iika. IW., on the termination of the
coccyx, t. 29.

INDEX.

415

Lust, instinct of, i. 85.

Ltjxuey, comparatively innocuous, i. 164.

iA/cama, Bexual differences of coloring in
species of, i. 378.

Ltell, Sir C., on the antiquity of man, i.
3 ; on the origin of man, i. 4 ; on the par-
allelism of the development of species and
languages, i. 57 ; on the extinction of lan-
guages, i. 58; on the Inquisition, i. 171 ;
on the fossil remains of vertebrate, i. 193 ;
on the fertility of mulattoes, i. 213.

Lynx, Canadian, throat-ruff of the, ii. 255.

Lybe-biej>, assemblies of, ii. 97.

M.

Jfacacus, ears of, i. 22 ; convoluted body in
the extremity of the tail of, i. 29 ; varia-
bility of the tail in species of, i. 144 ; whis-
kers of species of, ii. 269.

Macaeu8 cynomolgus. superciliary ridge
of, ii. 303; beard and whiskers of, be-
coming white with age. ii. 304.

ifacaeus vnornatw, i. 145.

Maeacus lasiotus, facial spots of, ii. 295.

ifacaeus radiatus, i. 184.

Maeacus rhesus, sexual difference in the
color of, ii. 279, 295.

Macalisteb, Prof, on variations of the
palmaris aceessorius muscle, i. 105; on
muscular abnormalities in man, i. 123,
124; on the greater variability of the
muscles in men than in women, i. 266.

Macaws, Mr. Buxton's observations on, i.
76; screams of, ii. 5S.

McCann, J., on mental individuality, i. 61.

■Mi f i.m.i.am). J., on the Indian cyp'rinida-,
ii. 17.

MACcuLLOcn, Colonel, on an Indian village
without any female children, ii. 348.

Maccullocu, Dr., on tertian ague in a dog,
i. 13.

Maggilliveay, "W., on the vocal organs of
birds, i. 57; on the Egyptian goose, ii.
44; on the habits of woodpeckers, ii. 6(1;
on the habits of the snipe, ii. 61 ; on the
whitathroat, ii. 66; on the moulting of
the snipes, ii. 79; on the moulting of the
anatidH!, ii. 81 ; on the finding of new
mates by magpies, ii. 99; on the pairing
of a blackbird uud thrush, ii. 100; on pled
ravens, ii. 121 ; on the guillemots, ii. 122 ;
on the colors of the tils, ii. 166; on the
immuturo plumage of birds, ii. 178; et
MQQ,

MtH-hrtts, sexes and young of, ii. 207.

Machetes jnignax, numerical proportion
of tho sexes In, I. 297; supposed to be
polygamous, 1. 261; pugnacity <>f the
male, ii. 39; doable moult in, n.' 7\

Hju kintohii, on tin- moral sense, I. 67.

>1 a< l,A( ni.AN, K., on Anatania mulirbrl*
and Jioreus hyrumlis, I. il(>6; on tho
Jinul appendages of mull' InscctM, I. JliW;

on th« pairing of dragon Hies. I. 88T; mi
dragon tiles, 1.851, 862; on dimorphism
•hi 4 prion, L86S; on tot want of pugna-

city in male dragon-flies, i. 353 ; on tho
ghost-moth in the Shetland Islands, i.
390.

McLennan, Mr., on the origin of the be-
lief in spiritual agencies, i. 63 ; on the
prevalence of licentiousness among sav-
ages, i. 92, ii. 342 ; on infanticide, i. 129,
ii. 347; on the primitive barbarism of
civilized nations, i. 174 ; on traces of the
custom of the forcible capture of wives,

i. 175, ii. 349 ; on polyandry, ii. 349,

M< Xkill. Mr., on the use of the antlers of
deer, ii. 242; on the Scotch deerhound,

ii. 249 ; on the long hairs of the throat of
the stag, ii. 256; on the bellowing of
stags, ii. 261.

Macrorhinus proboscideus, structure of

the nose of ii. 265.
Magpie, power of speech of, i. 57; stealing

bright objects, ii. 107; nuptial assemblies

of, ii. 98 ; new mates found by, ii. 99 ;

young of the, ii. 200 ; coloration of the,

ii. 220.

Magpies, vocal organs of the, ii. 52.

Maillaed, M., on the proportion of the
sexes in a species of Papilio from
Bourbon, i. 301.

Maixe, Mr., on the absorption of one tribe
by another, i. 154; on the want of a de-
sire for improvement, i. 160.

Makalolo. perforation of the upper lip by
the, ii. 325. •

Malae bone, abnormal division of, in man,
i. 119.

Malay Archipelago, marriage-customs of
the savages of the, ii. 357.

Malays, line of separation between tho
Papuans and the, i. 210; general beard-
lessness of the, ii. 306; staining of tho
teeth among, ii. 323; aversion of some,
to hairs on the face, ii. 332.

Malays and Papuans, contrasted charac-
ters of i. 208.

Male animals, struggles of. for the posses-
sion of the females, i. 251, 252; eager-
ness of, in courtship, i. 968, 264 ; gener-
ally more modified than female, i. 264,
266; differ in the same way from females
and young, i. 276.

Male characters developed in females, i.
271; transfer of to female birds, ii. W>.

Mali:, sedentary, of a In, inciioptcmus
parasite, i. MB.

Malkkactoks, i. 165.

Malls, presence of rudimentary female

organs in, i. 200.
M ali h and females, comparative mortality

of while young, i. 255. 267; comparative

numbers of, L 888, 255.
Malmi-kiie, on the woodpeckers, ii. 166.
Maltih h, T., on the rate of Increase of

population, I. 126, 127, 129.

M M I Kill I . Ili.lili.'.ili r the, ii. 161.

Malurvs, young of w. 207.

M \mm a, i. 246 ; rndlnu ntai v , in mala

mammals, L 17, 80, LM BOf I Mipernu-
meniiv . in ». nn. 11, 1. 120; of male hu-
man subject, I. 125.

41C

INDEX.

Mammalia. Tn>f. Owen's classification of,

L 180; genealogy of the, 1. 195.
Mammals, secondary sexual characters of,

ii. 22"»; wcajHUis of. li. 2:50; recent and
tertiary. roin|iarison of cranial rapacity
of, i. 140; relative size of the sexes of,
11. 248 ; pursuit of female, by the males,

i. 268; parallelism of, with binls in sec-
ondary sexual characters, ii. 2S8; voices
of, used esixviallv during the breeding-
season, li. 816, 817.

M\s. variability of. i. I'M; erroneously re-
garded as more domesticated than other
animals, i. 107; definitive origin of. i.
226 ; migrations of, 1. 181 ; wide distribu-
tion of, i. 182; causes of the nakedness
of. i. 148; supposed ]>hysical inferiority
of, i. 150; numerical proportions of the
sexes in, i. 'J.V>; h iiu-inUr of the Catar-
rliine group, early progenitors of,

1. 198; secondary sexual characters of,

ii. 801 ; primeval condition of, ii. 851.
Mandans, correlation of color and texture

of hair in the, i. 289.
M amu n i.K, left, enlarged In the male of

Ttijittroi/crr* tlixtortiiM, I.
M wmiii.Ks, use of the. in Am mo/>n Ha, i.

:t:t-2; large, of < 'uryilali* corn iitiut, i.

882; large, of male Lucunws ehtphue, i.

888.

Mandrill, nnml>cr of caudal vertebras In
tiie, i. 144; colors of the male, ii. 279,
282,895.

M ANTE4JAZZA, Prof., on the ornaments of
savages, ii. 822, et seya. on the beard-
lewicss of the New -Zcalaiidcrs. ii. :t<2;
on the exaggeration oi natural characters
by man, 11. 885.

Mantell, W., on the engrossment of pret-
ty girls by the New -Zealand chiefs, li.
852.

M tint in, pugnacity of species of, 1. 849.
Maxccs Amelias, on the origin of the

moral sense, 1. 68; on the influence of

habitual thoughts, 1. 97.
Martca Penelope li. 109.
Marks, retained throughout groups of

birds, 11. 126.
Marriage, Influence of, upon morals, i.

92; restraints uj>on, among savages, 1.

12H; influence of, on mortality, i. 169;

development of. ii. :U.r>.
Marriages, communal, ii. 842, 844; early,

L 168.

M tusiiALL, Mr., on the brain of a Hush-
woman, i. 21N.

Marsupials, 1.194; possession of nipples
bv. i. 2»1 ; their origin from Moiiotrcina-
ta, L 804; uterus ot, L 118; development
of the nictitating membrane In, L 28 ; ab-
dominal sacs of L 246; relative size of
the sexes of, ii. 248; colors ot; U. 872.

Marsupium, rudimentary, in male marsu-
pials, L 199.

Marti if, W. C. I*, on alarm manifested by
an orang at the sijrht of a turtle, i. 42';
on the hair In Ilylohtite*, 1. Ib6; on a
female American deer, 1L 246; on the

voire of Ifijhinat,* Off Hi*, li. 264; on
Si mnojiithtriiM ntinaim. ii. -J'.'T.

Martin, on the I Hards of the inhabitants
of St Kilda, 11. 806.

Martins deserting their young. I. 80.

Martins, <.'_, on death caused by Inflam-
mation of the vermiform upjHudagc, i.
87.

Mastoid processes In man and ojhs, i.

188.

Mavosley, Dr., on the influence of the
sense of smell in man. i. 28; on Ijmni
liridgman, i. 57; on the development of
the vocal organs, i. 67.

Mayers, W. V., on the domestication of
the gold II sh in China, ii. 16.

Mayiiew, H, on the affection between
individuals of different sexes in the dog,
11. 258.

Maynard, CM., on the sexes of Chryte-

my» picta, iL 27.
Meckel, on correlated variation of the

muscles of the arm and leg, i. 125.
Mi nil INKS, etVret produced by, the same

in man and in monkeys, L 12.
V. tlumv, bright colors of some, i. 818.
Mr.(. ALiTiuo structures, provalenee of, 1.

224.

Jfeyafophn/s montana, sexual differences

in, ii. 25, 26.
Mi ynjiicuM ntl'nlu*, sexual difference of

color In, ii. 166.
Meyasoma, large size of males of 1. 887.
Meius, Dr. A_, on variation in the skulls of

the natives of America, L 104.
Meinecke. on the numerical projKirtion of

the sexes In butterflies, i. 800.
Melipiiaouke, Australian, nidiflcation of,

it. 161.

M.!,t.i. secondary sexual characters of, i.

822.

Mclo?, difference of color in the sexes of a

species of, i. 856.
Memory, manifestations of, In animals, i.

48.

Memxow, vonng. 1. 209.

Mental characters, difference of, in differ-
ent races of men, L 208.

Mental faculties, variation of. in the same
•pedal, L 85, 106; diversity of. in tbo
same race of men, L 105; inheritance of.
i. KM'i; similarin of the. in different races

of man, L 888; of birds, IL 108.
Mental powers, difference of, in the two

sexes in mun. 11. 810.
Men lira Alh.rti. ii. 9-; son- of. ii. .Vt.
Jfenwa tuperba, ||. 97, 9s ; long tails of

both Sexes of, ii. l.f>7.
Mki:«. ansk.il trachea of the male. ii. ,r>7.
Mi ran* ciiciillatiiM, speculum of. I. 2*d.
Meryu* mer gunner, young of. ii. 181.
Merganser terra tor, male plumage of, 1L

81.

M.taUura, splendid tail feathers of. 11. 14rt.
Methoca ichneumonide*, large male of, i.

887.

Mevem, M., en the dramming i.f the snipe,

11.61.

INDEX.

417

Mexicans, civilization of the, not foreign,
i. 175.

Meter, on a convoluted body at the ex-
tremity of the tail in a Macacm and a
cat, i. 29.

Meter, Dr. A., on the copulation of phry-
ganidai of distinct species, i. 332.

Migrations of man, effects of, i. 130.

Migratort instinct of birds, i. 76; van-
quishing the maternal, i. 80, 87.

Mill, J. 8., on the origin of the moral
sense, i. 68 ; on the " greatest happiness
principle," i. 93; on the difference of the
mental powers in the sexes of man, ii.
812.

Millipedes, i. 830. •

Milne-Edwards, H., on the use of the en-
larged chela of the male GeUvsimm, i.
322.

Milvago leucurue, sexes and young of, ii.
197.

Mimicrt, i. 397.

Mimm polyglottufi, ii. 105.

Mind, difference <>!'. in man and the highest
animals, i. 100 ; similarity of the, in dif-
ferent races, i. 223.

Minnow, proportion of the sexes in the, i.
299, 800.

Minnows, spawning habits of, ii. 15.

Mirror, larks attracted by, ii. 107.

Mivart, 8t. George, on the reduction of
organs, i. 18 ; on the ears of the Leinuroi-
dea, i. 23; on variability of the muscles
in Lemuroidea, i. 123, 131 ; on the caudal
vertebrae of monkeys, i. 144; on the
classification of the primates, i. 150; on
the orang and on man, I. 189 ; on differ-
ences In the lemuroidea, i. 190; on the
crest of the male newt ii. 23.

Mook!N(;-tiiiu kii. partial migration of, ii.
105; young of the, ii. 209.

Modifications, unserviceable, i. 147.

Moles, numerical proj>ortion of the sexes
in. 1. 296; battles of male, IL 228.

Mulli, uexia j>ttLiu;n»i><, sexual difference
in, ii. 9.

MOLLTTtOJu beautlAil colors and Shapes of,
i. 316; absence of secondary sexual char-
acters in the, i. 815.

Mou.i s< oida, 1. 197, 815.

Monaco nth hh muohih, and M. /Vrow//,
sexual difference s in, II. 12.

Mongolians, perfection of the senses in,
1.114.

Monkhy, protecting his keeper from a ha-
Imon, 1. 75, K4; Bonnet-, 1. 184; rhesus,
Sexual differeiiec ill color of the, Ii. 216.
296; mustaehc-, colors of the. II. '.'77.

M'nkkyh, liability or, to the tame dlseaeee
us man, I. 1 1 ; male, recognition of women
bv, I. 18; revenge taken bv, I. 89, ma-
ternal ulfeetlou in, I. 89: variability or the

t unity of attention in. I 48; using stonei
mid sticks, I. 49; Imitative faculties of, I.
M; signal a le* <.i; i. .v.; sentinels posted
by. 1. 71 ; dlroraity <•( the mental heal,
tles In, I. I or, ; mutual km. In. . m ,,| I
72; hands of Ihe, i. 184; breaking hart)

/raits with stones, i. 134; basal caudal
vertebrae of embedded in the body, i. 145 ;
human characters of, i. 184; gradation
of species of, i. 218; beards of, ii. 269;
ornamental characters of, ii. 291 ; analogy
of sexual differences of, with those of
man, ii. 303 ; different degrees of differ-
ence in the sexes of ii. 307 ; expression
of emotions by, ii. 320; generally mo-
nogamous habits of ii. 345 ; polygamous
habits of some, ii. 345 ; naked surfaces of,
ii. 360; American, manifestation of reason
in, i. 47 ; American, direction of the hair
on the arms of some, i. 1S5.

Monogamy, not primitive, i. 175.

Monogeni8T8, i. 220.

Mononychw pseudacori, stridulation of,

i. 371.

Monotremata, i. 194; development of the
nictitating membrane in, i. 23; lactifer-
ous glands of i. 200; connecting mam-
mals with reptiles, i. 204.

Monstrosities, analogous, in man and
lower animals, i. 109; caused by arrest of
development, i. 116; correlation of; i. 125;
transmission of, i. 216.

Montagu, G., on the habits of the black
and red grouse, i. 260; ou the pugnacity
of the ruff, ii. 89; on the staging of birds,

ii. 49 ; on the double moult of the male
pintail, ii. 81.

Monteiko, Mr., on Bucorax AbyxNinicti*.
ii. 69.

Months de Oca, M., on the pugnacity of

mali! Humming-birds, ii. 38.
MonMcola a/a m n, ii. 1 61,
Monuments, as traces of extinct tribes, 1.

228.

Moose, battles of, ii. 229; horns of the, an

incumbrance, ii. 24s.
Moral and instinctive impulses, alliance

of, i. 85.

Moral faculties, their influence on natural
selection in man, i. 152.

Mokal rules, distinction between the high-
er and lower, I. 96.

Molt a 1. sense, origin of the, 1. 9*: so called,
derived from the social instincts, i. !':{, 94,

Mm: m. tendencies, inheritance of. i. 98.

Mi minv. •gspOMd to t>c founded in sclf-
ishness, I. 93; test of. the general wel-
fare of* the community, i. 94 ; gradual rlM
of, i. 99; Infloanoe Of* high standard of
i. 159.

Morgan, L. H., on the Heaver, i. 36; on

the reasoning powers of the Bearer, l L">;
on the ttroIbM capture of wtree> L it.v,
on the oaitoronm of the Bearer, ii 986;
Doarriega noknown in prhMroJ times, it.

813; on Polyandry, Ii. >U9.
Mourns, V. 1 »., on hawks reeding an orphau

Beatttafi l*ti

Moii 1 u 1 1 \ . comparative, or female-, and

mai. s. 1 :•:.<:. 967, 999,

M0HT0N, oil Hie II mill Ml' of species of man,
.Von. •/<»/.! mooch i/< rtn, < h I. >i it. 1011- organs

or, ii. NT.

418

INDEX.

Motacilhr. Indian, young of. li. 1*2.

Minus, i. absence of mouth in some
mall', i. •-'Hi; apterous female, i. IT ; male,
prehensile use of the tarsi by, L 248 ; male,
attracted by females, i. 802; coloration
of, i. 865 ; sexual (inferences of color in,
L8S5.

Motmot, racket-shaped feathers in the tail
of a, 11. 70.

Moult, double, 11. ITS ; double annual, in

birds, ii. 77.
Moulting of birds, ii. 204.
Moults, partial, ii. 79.
M ud-tc btle, long claws of the male, ii. 26.
Mulattoes, persistent fertility of, 1. 218;

immunity of, from yellow fever, 1. 284.
Mi le, sterility and strong vitality of the, i.

218.

Mules, rational, 1. 47.

MCller, Ferd., on the Mexicans and Peru-
vians, 1. 176.

MCller, Fritz, on astomatous males of
lanai*, 1. 247; on the disappearance of
spots and stripes in adult mammals, ii.
290 ; on the proportions of the sexes In
some Crustacea, 1. 807; on secondary
sexual characters in various Crustaceans,
1. 819, et seqq. ; on the luminous larva of
a beetle, i. 885; musical contest between
male Cicada, L 841 ; on the sexual ma-
turity of young amphipod Crustacea, ii.
206.

MCller, J, on the nictitating membrane

and semilunar fold, 1. 28.
MCller, Max, on the origin of language,

i. 55; struggle for life among the words,

etc-, of languages, L 58.
MCi.i.kk. S.. on the Banteng. ii. 27C; on the

colors of ikmnopithcetu c/trt/notnelas, iL

277.

M it ntj Ac-peer, weapons of the, ii. 245.

Mi'RiE, J., on the reduction of organs, i. 18;
on the ears of the Lemuroldea, L 28 ; on
variability of the muscles of the Lemuroi-
dea, L 128, 181 ; basal caudal vertebrae of
Ma ca cuit inornatus embedded in the
body, i. 145 ; on differences in the Lemu-
roidea, 1. 190; on the throat-pouch of the
male Bustard, ii. 55; on the mane of
otaria jubata. ii. '_'.V> ; on the sub-orbital
pits of Buminants, ii. 267; on the colors
of the sexes in Otaria nigrescent, ii.
274.

Murray. A .. on the Pedicull of different
races of men, L 211.

jUi RRAT, T. A., on the fertility of Austra-
lian women with white men," I. 212.

Mum ro» inaa, i. 49.

Ma* in in utii*. sexual difference in the col-
or of, IL 278.

Muiwa romitoria, 1. 189.

Miixcicupa (frixn/a, ii. 16?.

Muncicapa luctuom, ii. 162.

Miutcicapa rutioUla, breeding In imma-
ture plumage, U. 205.

Muscle, iscbio-pubic, 1. 123.

Muscles, rudimentary, occurrence of, in
man, L 19; variability of the, i. 105; ef-

fects of use and disuse upon, 1. 112 ; ani-
mal-like abnormalities ot, in man, i. 122:
correlated variation of, in the arm and
leg, i. 125; variability of in the hands and
feet, i. 181 ; of the jaws, influence of, on
the physiognomy of the Apes, i. 189 ; ha-
bitual spasms of, causing modifications
of the fecial bones, i. 141 ; of the early
progenitors of man, i. 198 ; greater varia-
bility of the, in men than in women, i.
266.

Muhculub stern alis, Prof. Turner on the,

i. 19.

Music, i. 224; of birds, ii. 48; discordant,
love of savages for. ii. 64 ; different appre-
ciation of, by different peoples, ii. 818;
origin of, ii. ill, 821 ; effects of, IL 820.

Musical cadences, perception of, by ani-
mals, ii. 817; powers of man, ii. 814, et
*eqq.

Musk-deer, canine teeth of male, ii. 231,
24.r>. 246; male, odoriferous organs of the,

ii. 267 ; winter change of the, ii. 285.
Musk-duck, Australian, ii. 86; large size

of male, ii. 11 : of Guiana, pugnacity of

the male. ii. 41.
Musk-ox, horns of ii. 236.
Musk-rat. protective resemblance of the,

to a clod of earth, ii. 284.
Muwphaga; colors and nidiflcation of the,

ii. 168; both sexes of. equally brilliant, 11.

169.

Mi ssels opened by monkeys, i. 134.
Mustaciie-mo.nkev, colors of the, ii. 277,
296.

Mustaches. In monkeys, i. 1*4.
Muntela. winter change of two species of,
ii. 2*4.

Mi in \tio\s. healini; of. i. 18.

Mutillti hiinijimi. (.undulation of. i. ".V>.

Mi tillid.e, absence of ocelli in female, i.

881.

Mwttf-x carat/a, j>olvgamoiis, i. 2.V?; vo-
cal organs of, ii. 264; Ward of ii. 269;
sexual differences of color in, ii. 276 ;
voice of, ii. 816.

Mi/cett* stnicnlu*, sexual differences of
color in, ii. 276.

M ykiapoda, 1. 830.

If,

Nagell on the influence of natural selec-
tion on plants, i. 146; on the gradation
of species of plants, i. 219.

Nails, colored yellow or purple in part of
Africa, iL 822.

Naples, greater proportion of female Ulo-
gitimate children in, i. 292.

N Mtwii AU tusks of the. ii. 2M1. 287.

-N v-m. cavities. Irir-c size ,,). jn American
aborigines, i. 114.

Nascent organs, L 18.

N m iii'sirs. H. von. on the improved breeds
of pigs, L 222 ; on the breeding of domes-
tic animals, ii. 853.

Natural selection, its effects on the early

INDEX.

419

progenitors of man, i. 131 ; influence of,
on man, i. 145, 148; limitation of the
principle, i. 146; influence of, on social
animals, i. 149 ; Mr. Wallace on the limi-
tation of, by the influence of the mental
faculties in man, i. 152; influence of, in
the progress of the United States, i. 172.
Nattjral and sexual selection contrasted,
i. 269.

Naulette, jaw from, large size of the ca-
nines in, i. 122.

Neanderthal skull, capacity of the, i.
140.

Neck, proportion of, in soldiers and sailors,

NecropJiorus, stridulation of, i. 36T, 371.

Neetarinia, young of, ii. 182.

Kectarinice, niditication of, ii. 161 ; moult-
ing of the, ii. 79.

Negeo, resemblance of a, to Europeans, in
mental characters, i. 273.

Negro-women, their kindness to Mungo
Park, i. 91.

Negroes, character of, i. 208 ; lice of i. 212 ;
blackness of, i. 216, ii. 365; variability of,
i. 217, 218 ; immunity of, from yellow fe-
ver, i. 234 ; difference of, from Americans,
i. 238; disfigurements of the, ii.282; col-
or of new-born children of, ii. 302 ; com-
parative beardlessness of, ii. 306; readily
become musicians, ii. 318; appreciation
of beauty of their women by. ii. 328, 330;
idea of beauty among, ii. 331 ; compres-
sion, of the nose by some, ii. 335.

Neolithic period, i. 176.

Xeomorpha, sexual difference of the beak
in, ii. 37.

NephtHa, i. 323.

Nests, made by fishes, ii. 19: decoration
of, by Humming-birds, ii. 107.

Neitmeistkr, on a change of color in pig-
eons after several moultings, i. 2st.

Neuration, difference of. in the two sexes
of some butterflies and hymeuoptera, i.
337.

Neuroptkra, 1. 306. 350.

jVeurothemiH, dimorphism in. i. 352.

New Zealand, expectation by the natives
of. of their extinction, L 282; practice of
tattooing in, ii. 326; aversion of natives
of, to hairs on the face, ii. '.'•■VI; pretty
girls engrossed by the chiefs in, ii. 862.

Newton, A., on the throat -punch of the
male busturd, ii, 66 ; on the alfforci be-
tween the females of tWO Species of (Ar//-

votu*, Ii. 1*4; on the hablta of the phala-
popo, dotterel, and god wit, ii. 1 '.»."».
Nkwth, II. 23.

NiOHOUOW, Dr., on the non Immunity of
dark Kiiropeans from yellow fever, L 280.
Nictitating membrane, I. 28, 198.
Nii»in< a-iiov, of n-hes, ii. \> - relation of,

to color, II. I.V.i, 105; of llritiafa bird*. U.

in,

Ni'iii i iiriioN, cries of the, II. 48,

Nn.ii iisi, \i i . arrival of the male before

the female, I. 261 ; ohk 1 1 of Um long of

the, ii. 10,

Nightingales, new mates found by, ii.
101.

Night-jar. selection of a mate by the fe-
male, ii. Ill ; Australian, sexes o'f, ii. 197 ;
coloration of the, ii. 216.

Night-jars, noise made by some male,
with their wings, ii. 59 ; elongated feath-
ers in, ii. 69, 92.

Ntlghatt, sexual differences of color in the,
ii. 273.

Nilsson, Prof, on the resemblance of stono

aiTow-heads from various places, i. 224;

on the development of the horns in the

reindeer, i. 279.
Nipples, absence of, in Monotremata, i. 200.
Nuzscn, C. L., on the down of birds, ii. 77.
Nocture, brightly colored beneath, i. 385.
Noctutd-e, coloration of, i. 3S2.
Nordmann, A., on Tetrao urogalloides, ii.

96.

Nomadic habits, unfavorable to human

progress, i. 160.
Norway, numerical proportion of male and

female births in, i. 291.
Nose, resemblance of, in man and the apes,

i. 184; piercing and ornamentation of the,

ii. 325; flattening of the, ii. 335 ; very flat,
not admired in negroes, ii. 833.

Nott and Gliddon, on the features of Ka-
meses EL, i. 209; on the features of
Amunoph III., i. 210; on skulls from
Brazilian caves, i. 210; on the Immunity
of negroes and mulattocs from yellow fe-
ver, i. 234; on the deformation of the
skull among American tribes, ii. 336.

NirmuRANUi moiluaca, bright colors of, i.
81T.

Np.mkr alr, Roman, i. 175.

Ni NKMAYA, natives of, bearded, ii. 307, 332

O.

Oiikimkni'k, value of, i. 156.

Ohhervation, powers of, possessed by
birds, ii. 1(15.

Occupations, .sometimes it cause of dimin-
ished BtatUre, i. Ill; effect of, upon the
proportions of the ImmIv, i. 112.

Ocki.i.i, absence of, in female Mutilllda-, 1.
331.

OCEELXJ of birds, formation and \ ariahilit v

of the, ii. 1-6.
OOKLOT, sexual differences in the coloring

of the. ii. '.'7:1.

Oojfphapt Inphnl,.^ ii. ft,

Odok m \. i. .ioc.

Otltniixti.s jmfafitriii, sexual difference of

color in, I. 888,
Oimiii, correlation of, with color of -kin. I.

889; ••mined by makes in the breeding-

season, II. 2S; of mammals, II. 20.Y
OCt'iintliim ninth s, difference of color In

the s.Aes „\\ I. U.M .

Otdmia, ii. 216, ->\:.

Oltvikk, on Rounds produoad by HhnsMn

*/, !,, f,t. i. 8T8.
OmaiopUa brunnta, itridukUofl of, i.

889.

420

INDEX.

Onitis furcifer, processes of anterior fem-
ora of the male, and on the head and
thorax of the female, i. 301.

Onthophagus, i. 860.

Onthaphagm nnnji/,/: sexual differences
of, i. 868; variation in the horns of the
male, i. 860.

Ophidia, sexual differences of, ii. 27.

Oi'osscm, wide range of, in America, i.
211.

Optic nerve, atrophy of the, caused by de-
struction of the eye, i. 112.

Orang-Octan, il. 80S; Bischoff on the
agreement of tin- brain of the, with that
of man, i. 11; adult age of the, i. 13;
cars of the, i. 21 ; vermiform appendage
of, i. 26; platforms built by the, i. &5;
alarmed at the sight of a turtle, L 41 ;
using a stick as a lever, i. 49 ; using mis-
siles, i. 50; using the leaves of the Pan-
danus as a night covering, i. 51 ; hands
of the, i. 134; absence of mastoid pro-
cesses in the, i. 138; direction of the
hair on the arms of the, i. 185; its' aber-
rant characters, i. 188; supposed evolu-
tion of the, i. 222 ; voice of the. ii. 265 ;
monogamous habits of the, ii. 345 ; male,
beard of the, ii. 270.

Oranges, treatment of, bv monkeys, i.134.

Orange-tip butterfly, i. 876, 881.

Orchidia Darwinii, dimorphism of males
of, i. 822.

Orchidia Tucuratinga, limbs of, i. 320,

827.
Ordeal, i. 66.

Orean cfinna, colors of, ii. 274.

Oreas Derbianus. colors of, ii. 274, 2S6.

Organs, prehensile, i. 248; utilized for
new j)urj»oses, ii. 810.

Organic scale, Von Baer's definition of
progress in. i. 203.

Orioles, uidification of. ii. 160.

Oriolutt, species of. breeding in immature
plumage, ii. 205, 206.

Oriolus melanocephalus, coloration of the
sexes in, ii. 170.

Ornaments, prevalence of similar, i. 224;
fondness of savages for, ii. 824 ; of male
birds, ii. 47.

Ornamental characters, equal transmis-
sion of, to both sexes, in mammals, ii.
2S3; of monkeys, ii. 291.

Ornithoptera Croesus, i. 801.

Ornithorhynchus, i. 192; spur of tho
male, ii. 231 ; reptilian tendency of, L 196.

Orocetts erythrogastra, young of, ii. 210.

Orronv, Grotto of i. 28.

Omoilticiui at in, difference of color in tho
sexes of i. 857.

Ortuoptera, i. 841 ; metamorphosis of, i.
282 ; stridulating, auditory apparatus of,
i. 843; colors of, i. 849; rudimentary
stridulating organs in female, i. 849;
stridulation of the, and Uomoptora, dis-
cussed, i. 849.

Ortv.;"/ m's {/ul<iri#, pugnacity of the
male, ii. 42.

Qryctes, stridulation of, i. 369 ; sexual dif-

ferences in the 6tridulant organs of, i.
871.

Oryx leueoryx, use of the horns of, ii. 239.
251.

(>*/>/i ranter rii/iix, sexual difference in tho
color of, ii. 272.

Ostrich, African, sexes and incubation of
the, ii. 196.

Ostriches, stripes of young, ii. 176.

Otaria jubata, mane of the male, ii. 255.

Otaria nigrescens, difference in the colora-
tion of the sexes of, ii. 278.

01i* Ilenyalensis, love-antics of the male,
ii. 65.

Otis tarda, polygamous, i. 261 ; throat-
pouch of the male, ii. 55.

Ouzel, ring, colors and nidiflcation of the,
ii. 171.

Ouzel, water, colors and nidification of

the, ii. 162.
OrihoH moxchatus, horns of. ii. '_':'.o.
Ovipositor of insects, i. 246.
Oris cycloceros, mode of fighting of, ii.

238.

Ovule of man, i. 14.

Owen, Prof., on the Corpora Wolfliana, I.
16; on the great-toe in man, i. 16; on
the nictitating membrane and semilunar
fold, i. 23; on the development of the
posterior molars in different races of
man, i. 26 ; on the length of the caecum
in the Koala, i. 26 ; on the coccygeal ver-
tebrae, i. 29; on rudimentary structures
belonging to the reproductive system, i.
80; on abnormal conditions of the hu-
man uterus^i. 119; on the number of
digits in the Ichthyopterygia. i. 120 ; on
the canine teeth in man, L 121 ; on the
walking of the chimpanzee and orang, i.
134; on the mastoid processes in the
higher apes, i. 138; on the hairiness of
elephant- in elevated di>tri< ts, i. 1 43; on
the caudal vertebrae of monkeys, i. 144 ;
classification of mammalia, i. 180; on'
the hair in monkeys, i. 186; on the pis-
cine affinities of the Ichthyosaurians. i.
196 ; on polygamy and monogamy among
the antelopes, L 258; on the horns of
Antilocapra Americana, L 280 ; on the
musky odor of crocodiles during the
breeding-season, ii. 27; on the scent-
glands of snakes, ii. 29 ; on the Dugong,
Cachalot, and OrnWiorhynchiis, il. 281;
on the antlers of the red-deer. ii. 241 ; on
the dentition of the Camclidn>, ii. 246;
on the tusks of the Mammoth, ii. 247 ;
on the horns of the Irish elk, ii. 247 ; on
the voice in the giraffe, porcupine, and
Mag. ii. 261 ; on the laryngeal sac of the
gorilla and orang, ii. 263 ; on the odorifer-
ous glands of mammals, ii. 266, 267 ; on
the effect* of emasculation mi the vocal
organs of men, ii. 814; on the voice of
Hylobatis agilis, ii. 316; on American
monoiramous monkeys, ii. 345.

Owi.s. white, new mates (bund by. ii. 100.

O.ri/notim. difference of the tumales of two
specie* of, U. 184.

INDEX.

421

p.

Pachydermata, i. 259.

Paget, on the abnormal development of
hairs in man, i. 24 ; on the thickness of
the skin on the soles of the feet of in-
fants, i. 113.

Painting, i. 224.

Paiwmon, chelae of a species of, i. 321.
Palaiomis, sexual differences of color in,
ii. 221.

Palceamis Javanicus, color of beak of, ii.

Palceornis rosa, young of, 'ii. 180.
Palamedea cortiuta, spurs on the wings

of, ii. 44.
Paleolithic period, i. 176.
Palestine, habits of the chaffinch in, i.

298.

Pallas, on the perfection of the senses in
the Mongolians, i. 114; on the want of
connection between climate and the color
of the skin, i. 232; on the polygamous
habits of Antilope saiga, i. 258 ; on the
lighter color of horses and cattle in win-
ter in Siberia, i. 273 ; on the tusks of the
musk-deer, ii. 245, 246 ; on the odorifer-
ous glands of mammals, ii. 266 ; on the
odoriferous glands of the musk-deer, ii.
267; on winter changes of color in mam-
mals, ii. 2K4; on the ideal of female beau-
ty in North China, ii. 328.

Palrnaris aceessarius muscle, variations
of the, i. 105.

Pampas, horses of the, i. 227.

Pangenesis, hypothesis of, i. 271, 275.

Panniculus carnosus, i. 19.

Papilio, sexual differences of coloring in
species of, i. 377 ; proportion of the sexes
in North American species of, i. 301 ;
coloration of the wings in species of, i.
383.

Papilio aseaniite, i. 377.

PapiUo Sesostris and Children^, varia-
bility of, 1. 389.

Papilla Turn us, i. 301 .

Papilionid^e, variability in the. i. 389.

Papuans, line of separation between the.
and the Malays, 1. 210; beards of the, ii.
807 ; hair of, ii. 824.

Papuans and Malays, contrast in char-
acters of, 1. 208.

Paradise, Birds of, IL 96, 173; supposed
by Lesson to bo polygamous, i. 260; rat-
tang of their quills by. Ii. 58; racket-
shaped feathers In, il. 70; sexual differ-
ence! in color of, Ii. 71 ; decomposed feath-
ers In, II. 70, 93; display of plumage by
the Bttle, II. 85.

Paradlsea apoda, baibless feathers In the
tall of, II. 70; plumage of, II. 72; and /'.

Papuana. divergence of the females of,

II. [84

Parad4$sa rubra, il. 71, 72.

Paua<;iiay, Indians of, eradication of eye-
brows and eyelashes by, ii. 889.

Pah akp.kt, Australian, variation in the col
or of the tilths of a main, ii. 191.

Parallelism of development of species
and languages, i. 57.

Parasites on man and animals, i. 12 ; as
evidence of specific identity or distinct-
ness, i. 211; immunity from, correlated
with color, i. 233.

Parental affection, partly a result of natu-
ral selection, i. 77.

Parents, age of, influence upon sex of off-
spring, i. 293.

Paring, sexual difference of color in, ii. 166.

Park, Mungo, negro women teaching their
children to love the truth, i. 91 ; his treat-
ment by the negro women, i. 91, ii. 311 ;
on negro opinions of the appearance of
white men, ii. 330.

Parrot, racket-shaped feathers in the tail
of a, ii. 70 ; instance of benevolence in a,
ii. 105.

Parrots, imitative faculties of. i. 43 ; chancre
of color in, i. 146 ; living in triplets, ii. 102 ;
affection o£ ii. 104; colors of, ii. 213 ; sex-
ual differences of color in, ii. 221 ; colors
and nidification of the. ii. 163, 166, 168;
immature plumage of the, ii. 180 ; musi-
cal powers of, ii. 319.

Parthenogenesis in the Tenthredinae, i.
305 ; in Cynipidse, L 305 ; in Crustacea, i.
306.

Partridge, monogamous, i. 261 ; propor-
tion of the sexes in the, i. 297 ; female, ii.
186.

" Partridge-dances,1' ii. 65.

Partridges, living in triplets, ii. 102 ; spring
coveys of male, ii. 103; distinguishing
persons, il. 106.

Parus eanUeut, ii. 166.

Passer, sexes and young of, ii. 203.

/'i/.v.v/ /• braehydarti/hts, ii. 203.

Passer domesticus, ii. 162, 203.

Passer mo)i1<innx, ii. 162. 203.

Patagonians. self-sacrifice by, i. 84.

Patterson, Mr., on the A grion id<x, i. 351 .

Paulistas of Brazil, i. 21 6.

I'm;, rristati/s, i. 2sl, ii. 130.

Paro muticus, i. 290, ii. 130; possession of
spurs by the female, ii. 44, 155.

Paro nigripenuis, ii. 115.

Pavaguas Indians, thin legs and thick arms
of I lie, i. 112.

Payan, Mr., on the proportion of tin feme
in sheep, i. 295.

Peacock, polygamous, I. 261 ; sexual char-
acters of, i. 2*1 ; pugnacity of the..ii. M ;
rattling of the (piills bv, ii". 5s ; elongated
tail-coverts of the, ii. 69. 93; love of dis-
play of the, II. 130, 65, S3; occllated spots
of the, ii. 130; inconvenience of long tail
of the, tO the female, ii. 1 17, 1ST. I.Vs
continued Increase of beauty of the. il.
206.

Pi: wock hi ttit.i i v. i. 3*0.

Pkai-'ow i.. prefer*] t females for a panic -

ular male. ii. 116; Ihsi BdTaneeS made by

the female, ii. Lift,

Pediculi of domestic animals mid man, I.
tit

lY.Mi.Ki i. of man, i. '.'o.">.

422

INDEX.

Pt<lionomu« tnrquata*, sexes of, li. 192.
Peewit, wing-tubercles of the male, 11.
44.

Pklaotc animals, transparency of, 1. HI 1.

I'eltcanuM eri/throrhyncJiti*, horny crest
on the beak of the male, during the" breed-
ing-season, ii. 76.

PeUvaniM onocrotalus, spring plumage of,
li. 81.

PelelG, il. 825.

Pelican, blind, fed by his companions. 1.

74; young, guided by old birds, i. 74;

pugnacity of the male, 1L 41.
Pelicans, fishing in concert, i. 72.
lohiim Iltrmanni, siridulation, of. i.

870.

Pelvis, alteration of, to suit the erect atti-
tude of man, i. 187 ; differences of the, in
the sexes in man, il. 802.

PentU>p» nigra, sound produced by tho
male, ii. 61.

Pennant, on the battles of seals, ii. 229 ; on
the bladder-nose seal, ii. 265.

Penthe, antennal cushions of the male, L

Pkrch, brightness of male, during breeding-

season, ii. 13.
Pereokine Falcon, new mate found by, 11.

100.

Period of variability, relation of, to sexual
selection, i. 257.

Periodicity, vital Dr. Laycock on, 1. 12.

Periods, lunar, followed "by functions in
man and animals, i. 12, 204.

Periods of lift', inheritance at correspond-
ing, i. 271, 276.

J'cri*oreus CunadetmA, young of, ii.
200.

J', titrifh'm, difference of color in the sexes

of a species of, i. 366.
Periwinkle, 1. 815.
/', rit 'iM cri*tut<i, ii. 121.
Pekskvkuax e, ii charact. ri.-tic of man. ii.

812.

Persians, said to be Improved by Intermix-
ture with Georgians and Circassians, IL
841.

Personnat, Mn on Bombwe Yamamai, L
801.

Peruvians, civilization of the, not foreign,
L176.

Petrels, colors of, IL 220.
J'.triH-hu-lo .'»/.///<</. voung of. ii. 210.
Petrimia, ML 208.

Pkeiffer, Ida, on Javanese ideas of beautv,
il. 881.

Phaeochsmu jEthiopicu*, tusks and pads
of, IL 258.

Pii ai. anger, Vulpine, black varieties of the,
IL 280.

Pfuilaropiu fulicariu*, ii. 194.
Phalaropu»h\ip*rbortuK, IL 194.
Phantom, L 861.

Phanceu* earnf/m, variation of tho horns

of the male, I. 869.
PhnrutM /a tin tut, sexual differences of, I.

MB.

Phamzm fancier, L 850.

Phatgonura riridi/mina, strid illation of,

i. 844, 845.

1'httninnuM S-rmm,rringii, ii. 150.

Phamanu* rrnrteolor, IL 85.

I'haHianm W,i//i,-J,ii. ii. K». 1S7.

PiiASMio.t; mimicry of leaves by the, 1.401.

Pheasant, polygamous, L 261 ; 'production
of hybrids wfth the common tt>wL ii. 1 17 ;
and 'black grouse, hybrids of. II. 109; im-
mature plumage of the, li. 180.

Pheasant, Argus, ii. 69, 178; display of
plumage by the male, 11. 88; oeejjHted
spots of tho« ii. 128, 185; gradation of
characters in the, II. 185.

Pheasant, Blood-, il. 42.

Pheasant. Cheer, ii. *'.». 1-7.

Pheasant, Eared, L 290; IL 89, 187 ; sexes
alike in the, li. 170; length of the tall in
the, iL 158.

Pheasant, Golden, display of plumage by
the male. ii. sT.; sex of young, ascer-
tained by pulling out head-feathers, il.
205 ; age of mature plumage in the, 11.
204

Pheasant, Kalij, drumming of the male,

il. 59.

Phi \- vn r, Pci \ es, 1. ngth of the tail in, ii.

158.

Pheasant, Silver, sexual coloration of the,

ii. 218; triumphant male, defused on ac
count of spoiled plumage, li. 115.

I'm: \- vm. Nemmei hiil's. ii. 1 !'.». l'>s.
Pheasant, Tragopan, ii. 68; display of

plumage bv the male. ii. -7; markings

of the sexes of the, 11. 128.
Pheasants, perij>d of acquisition of malo

characters in the family of the. i.2^0;

projiortion of sexes In chicks of, L 297 ;

length of tho tail In, IL 149, 157, 1>.
PhihulromuM, i. :tj>.
Philters, worn by wjmen, 11. 828.
J'Ihhui <ir<i nliiii'li-:!. M-xu.il ilitlerence in

the coloration of ii. -JT:!.
Phirnicura ruticilla. ii. 101.

PnosPHoaaeoKNCR of Insects, L 845.

PiiKYii aniii.k, copulation of distinct spe-
cial of, L 882.

Phryniscu* nigricans II. 24.

Physical inferiority, supposed, of man, i.
149.

Pickering, on the number of species of

man, L 218.
Picroir, J. An on the soul of man, IL 8T8.
I'ii'n* it unit it*, ii. 41.
PIERID.K, mimicry by female, I. 899.
Pi*ri*,\ 880.

Pigeon, carrier, late development of the
wattle In, L 284; domestic, breeds and
subbreeds of, IL 170; pouter, late de-
velopment of the crop In, L 284 ; female,
deserting a weakened! mate, L 254.

Pk.i.mns. nestling, fed by the Secretion of

the crop of both parents, L 202; changes
of plumage In, L 272; transmission of
sexual peculiarities In, L 274 ; changing
color after several mo ul tings, L 284; nu-
merical proportion of the sexes in, L 296;
cooing of, il. 58; variations in plumage

INDEX.

423

of, ii. 71 ; display of plumage by male, ii.
92; local memory of; ii. 105; antipathy
of famale, to certain males, ii. 114; pair-
ing of, ii. 115; profligate male and
female, ii. 114 ; wing-bars and tail-feath-
ers of, ii. 125; supposititious breed of, ii.
148; pouter and carrier, peculiarities of
predominant in males, ii. 150; nidifica-
tion of; ii. 160 ; immature plumage of the,
ii. 180; Australian, ii. 167; Belgian, with
black-streaked males, i. 285, 293 ; ii. 150.

Pigs, origin of the improved breeds of i.
222 ; numerical proportion of the sexeg
in, i. 295; stripes of young, ii. 176, 288 ;
sexual preference shown by, ii. 260.

Pike, American, brilliant colors of the
male, during the breeding-season, ii. 14.

Pike, male, devoured by females, i. 299.

Pike, L. O., on the psychical elements of
religion, i. 66.

PimeUa striata, sounds produced by the
female, i. 373.

Pintail Drake, plumage of, ii. 81 ; pairing
with a wild-duck, ii. 110.

Pintail Duck, pairing with a "Widgeon, ii.
109.

Pipe-fish, filamentous, ii. 18; marsupial

receptacles of the male, ii. 20.
Pipits, moulting of the, ii. 79.
Pipra, modified secondary wing-feathers

of male, ii. 62.
Pipra deliciom, il. 62, 68.
J 'irate* *tridulu#, stimulation of. i. 340.
Pitfieoia leuoocephala. sexual differences

of color in, ii. 277.
Pithecia Satana*, beard of. ii. 269, 27.' ;

resemblance of, to a negro, ii. 365.
Pith, suborbital, of Kuminants, ii. 267.
PmiD.a, niditication of, ii. 160.

Pl. \< KNTATA, i. 194.

Plaoiohtomoiw fishes, ii. 1.
Plain- wanderer, Australian, ii. 192.
Planarias, bright colors of some, i. 818.
Plantain-eatkrh, colors and nidification

of the, 11. 163; both sexes of, equally

brilliant, ii. 169.
Plants, cultivated, more fertile than wild,

L 127; Nflgcll, on natural ■election in. i.

146; male (lowers of. mature before the

female. I. '252; phenomena of fertilization
In. I. 265; relation between number end

size of needs In, I. 309.
Platal4a, ii. 57; change of pi age In, il.

I'hitijhh mnuA, I. 350.
J'/ah/irrniM, young of, II. 200.
PUttifphyllum amen rum, I. 312, 315.
Pi \ i v ftUJjri monkey*. I. 188.

PxATYiMi mvoidta, I 19,

J'liCtmlomiiH, head tenia. I. s of (lie mnlo of

u ipeefei of, IL io.

I'lrraxtonuiM Itarliatim, peculiar braid of

(be male, II. 10.
J'/rrtm/iUnt* aaml>,n*i»t spurred wind's

of, H 44.

/'/.„; im. II. M.

P&oraa. trine pun "f, IL 14: doubU

moult In, II. 79.

Plumage, changes of, inheritance of, by
fowls, i. 272; tendency to analogous
variation in, ii. 70; display of, by male
birds, ii. 82, 92 ; changes of, in relation to
season, ii. 172; immature, of birds, ii.
175, 179; color of, in relation to protec-
tion, ii. 213.

Plumes on the head in birds, difference of,
in the sexes, ii. 156.

Fneumora, structure of. i. 346.

Podica, sexual difference in the color of
the irides of ii. 123.

Poeppio, on the contact of civilized and
savage races, i. 230.

Poison, avoidance of by animals, i. 48.

Poisonous fruits and herbs avoided by
animals, i. 35.

Poisons, immunity from, correlated with
color, i. 233.

PoLisn fowls, origin of the crest in, i. 275.

Pollen and Van Dam, on the colors of Le-
mur macaco, ii. 276.

Polyandry, ii. 349 ; in certain cvprinida?,

i. 306 ; among the elateridie. i. 305.

Polydactylism in man, i. 120.

Polygamy, influence of, upon sexual selec-
tion, i. 257; superinduced by domesti-
cation, i. 262; supposed increase of fe-
male births by, i. 293 ; in the stickleback,

ii. 2.

POLYGENISTS, i. 220.

Polynesia, prevalence of infanticide in, ii.
847.

Polynesians, aversion of, to hairs on the
face, ii, 882; wide geographical range of,

i. 10 s; difference of stature among the. i.
110; crosses of, i. 217; variability of, i.
217; heterogeneity oft he. L 282. *

Polyptertron, display of plumage by the
male. ii. B6j Dumber of span in. ii. 4?;
gradation of characters in, ii. 131 ; female
Of, ii. 185.

J'oh/pitctroi) dMnquU. ii. BS. 182, 188.

Puli/plvctroti Ilardirirkii. ii. 132. 133.

/'<>/>//,/,, -trail Mahl<;;i,s<: ii. 133. 134.

Polijplertroii Xapoteoni«, ii. 132, 1:14.

Poi.v/oa, i. 315.

J'oiitajiorcia ajfini*, i. 319.

Poki i i-iNK, miitc, except in the rutting-

sea.son, ii. 261.
Poi:i:s, eXOretorT. numerical relation of, to

the hairs in .sheep, I. 189.

PorpitOy bright colors of some, i. 818.
Portax jiicta, dorsal crest and throat lull
of, II. '26s; hc.xuuI differences of color In,

ii. 2Ti. nil

I'ortiiniiM putirr, pugnacity of, I. 323.

I'otainorlith-rim /niiii-i/tatim, tuskn mid
l.i. i ll knobl of I he. II. 2.M.

POCOIOT, *'<■. OH the ratio of Instln, t and
Intelligence, I. 36; on the Instincts of
ants, I. |H0; ou (he eaves of lbon Him-
bel, 1.209; on the liiiinunlt v of nrgroe.i

feOtn Vellou lever. I .Ml.

Pol nr. pu i. Into development of til*

I li ce crop III, I. 2s|.

Pnw i i Hi on He dill. 1 1 ni . oloi ,.| ill.

Hc\es In a specie* of .\/ltill,l, I, 1126.

424 INDEX.

Powtb, Mr., on tho habits of the chaffinch
In Corfu, i. 29$.

Phkkminkm k of man. i. 1:51.

Preference for males by female birds, ii.
108, 117; shown by mammals, in pair-
ing 11. 266.

Prehensile organs, i. 24$.

J'nx''i/(/M i nttHiiM. lighting of the male. ii.
809.

Preyer, Dr., on supernumerary mammae
in women, 1. 120.

Prichard, on the difference of stature
among the Polynesians, 1. 110; on the
connection between the breadth of the
skull in the Mongolians and tho perfec-
tion of their senses, i. 114; on tho ca-
pacity of British skulls of different opes,
1. 140 ; on the flattened heads of the
Colombian savages, ii. 824; on Siamese
notions of beautv. ii. 829 ; on the beard-
lessness of the Siamese, ii. 882 ; on the
deformation of the head among Ameri-
can tribes and the natives of Arakhan, ii.
885.

Primary sexual organs, i. 246.
Primates, L 188; sexual differences of

color in, ii. 277.
Primogeniture, evils of, i. 163.
J'rimuhi, relation between number and

size of seeds in, i. 809.
Prionidjs, difference of the sexes in color,

i. 856.

PrtH-tntretttfi multimaculatu*. ii. 24. :!.">.
Proctotretim tenuis, sexual difference in

the color of, ii. 85.
Profligacy, i. 166.
Progenitors, early, of man, i. 198.
Progress, not the normal rule in human

society, i. 160; elements of, i. 170.
Prono-uorn, horns of. i. 280.
Proportions, difference of, in distinct

races, i. 20*.
Protective coloring in butterflies, i. 8!i2 ;

in lizards, ii. 85; in birds, ii lbS, 214 ; in

mammals, ii. 2*:i, 2*4.
Protective nature of the dull coloring of

female Lcpidoptera, i. 890, 892. 401.
Protective resemblances in fishes, ii. 18.
Protozoa, absence of secondary sexual

characters in, i. 812.
Pruner-Bey, on the occurrence of the

supra-condvloid foramen in the humerus

of man, i. 28; on the color of negro in-
fants, ii. 808.
Prussia, numerical pm->ortion of male and

female births In. i. 292.
Ptocut, proportions of the sexes in, i.

806.

Ptarmigan, monogamous, i. 261 ; summer
and winter plumage of the, ii. 78, 79;
nuptial assemblages of, ii. 97 ; triple
moult of the, ii. 178; protective colora-
tion of. It. 169.

Ptft-bixds, colors and nidlficatlon of the,

ii. 168.

Pugnacity of fine plumaged male birds,
ii. »'.».

Pumas, stripes of young, it 175.

Puprnw learning from cats to clean their

fiices, t. 48.
PyvnonotuH larmorrhoux, pugnacity of

the male, ii. 39; display of under-tail

coverts by the male, ii. 91.
Pi/ranya (F*tird, male aiding in Incuba-

tion, ii. 159.
J'i/ro</eM, difference of the sexes in color,

i-856.

Q.

Qc \iM-.t man \. hands of. i. 134; differences
between man and the, i. 1*3; dependence
of, on climate, i. 210; sexual differences
of color in. ii. 276: ornamental charac-
ters of. ii, 291 ; analogy of sexual differ-
ences of. with those of "man. ii. :{<>:»: fight-
ing of males for the females, Ii. :;o9; mo-
nogamous habits of. ii. 345; beards of the,
ii. 861.

Qua in. R.. on the variation of the muscles
in man, I. 105.

Qu ATREFAG es, A. dc. on the occurrence of
a rudimentary tail in man, i. 28; on t lie
moral sense as a distinction between
man and animals, i. 67; on variability, i.
]o>; on the fertility of Australian women
with white men, i. 213; on the Paulistas
of Brazil, i. 216; on the evolution of the
breeds of cattle. I. 222; on tho Jews, i.
288; on the liability of negroes to tropi-
cal fevers after residence in a cold cli-
mate, i. 284; on the difference between
field- and house-slaves, 1.237; on the in-
fluence of climate on color, i. 2:57; on the
Ainos, ii. 306; on tho women of San
(tiuliano, ii. 841.

Qukchua Indians. 1. 114; local variation of
color in the, i. 2:57; no grav hair among
the. ii. 320; hairlessness of the, ii. 807;
long hair of the, II. 881 .

Qiten/uivfula acuta, ii. 109.

(juiMcalu* major, proportions of the sexes
of, in Florida and Honduras, i. 298.

It.

Rabbit, white tail of the, H. 2M.

Rabbits, danger-signals of, 1. 71 ; domestic
elongation of the skull in, i. 142; modifi-
cation of the skull in. by the lopping of
the ear, I. 142; numerical projjortion of
the sexes in, I. 295.

Races, distinctive characters of, I. 206; or
s-M'cicM of man. i. 210; crossed, fertility
or sterility of, i. 212; of man. variability
of the, L 217; of man, resemblance of, in
mental characters, L 228 ; formation of, 1.
225; of man. extinction of, I. 226; effects
of the crossing of, i. 281 ; of man. forma-
tion of the, i. 281 ; of man. children of
the, it. 808; beardless, aversion of, U
hairs on the lace, H. 888.

Raffles, Sir S., on the Banteng, ii. 276.

Rafts, use of, L 182, 225.

Rags, manifested by animals, i. 89.

INDEX.

425

Ttaia batis, teeth of; ii. 6.

Rata chtvata, female spined on the back,

ii. 2; sexual difference ia the teeth of,

ii. 6.

Raia maculata, teeth of, ii. 6.
Kails, spur- winged, ii. 44.
Kam, mode of fighting of the, ii. 288 ; Afri-
can, mane of an. ii. 271 ; fat-tailed, ii. 271.
Rameses II., i. 209.

Kamsay, Mr., on the Australian Musk-
duck, ii. 315; on the Regent-bird, ii. 108;
on the incubation of Menura superba,
ii. 157.

Rana esculenta, vocal sacs of, ii. 26.
Rat, common, general dispersion of. a

consequence of superior cunning, i. 49;

supplantation of the native, in New

Zealand, by the European rat, i. 2-31;

common, said to be polygamous, i. 259;

numerical proportion of the sexes in, i.

296.

Kats, enticed by essential oils, ii. 267.

Rationality of birds, ii. 104.

Rattlesn akes, difference of the sexes in
the, ii. 28 ; said to use their rattles as a
sexual call, ii. 28.

Raven, vocal organs of the, ii. 52 ; stealing
bright objects, ii. 107 ; pied, of the Feroe
Islands, ii. 121.

Rays, prehensile organs of male, ii. 1.

Razor-bill, young of the, ii. 208.

Reade, Winwood, on the Guinea sheep, i.
280; non-development of horns in cas-
trated male Guinea-sheep, ii. 236; on the
occurrence of a mane in an African ram,
ii. 271; on the negroes' appreciation of
the beauty of their women, ii. 828; on
the admiration of negroes for a black
skin, ii. 330 ; on the idea of beauty
among negroes, ii. 834; on the Jollof's,
ii. 341 ; on the marriage-customs of the
negroes, ii. 857.

Reason, in animals, i. 45.

Redstart, American, breeding in Imma-
ture plumage, ii. 205.

Redstarts, new mates found by, ii. 101.

Rkduvid.e, stridulatlon of, i. 840.

Bed -BUB tin*;, head-leathers of 1 1 1 * - male,
ii. 91 ; attacked by a bullfinch, ii. loo.

Bam, fishes frequenting, ii. 17.

Regeneration, partial, of lost parts in
mini, i. 13.

Re*;ent-iiiri>, II. 106.

Reindeer, antlers of, with numerous
points, II. 241 ; sexual preferences shown

by, II. '^<"HI; bonis of Hi.', i. 879: winter

change <»f the, li. 884: battles of, ii. 889;

horns of tin- female, II. 883.

Ki i.a rioNhiiip, terms of, II. 31 1.
Kei.h.io.v, deficiency of, among certain
races, I. 62; psychical dements of, I. 80.
RufOBSB, I. *7; dulldcncy of, a ng sav-

lltfeH, I. U)S.
KeNOOKR, Oil the diseases of t t biiM AxiM',

I. li; on maternal sflbctlon In a Ctbut, I.
39; revenue taken by monkeys. L 88; on
tin" Masoning powers <>( Ajnerioaa moo

keys, I. 15; on Hie OSS of BtQOSJ bj BMfl

keys for cracking hard nuts, i. 49; on
the sounds uttered by Cebus Asarce, i.
52 ; on the signal-cries of monkeys, i. 55 ;
on the diversity of the mental faculties
of monkeys, i. 106 ; on the Payaguas In-
dians, i. 112 ; on the inferiority of Euro-
peans to savages in their senses, i. 114;
on the polygamous habits of Mycetes
caraya, i. 258 ; on the voice of the howl-
ing monkeys, ii. 264; on the odor of
Cervus campestris, ii. 266 ; on the beards
of Mycetes caraya and Pithecin 8a-
tanas, ii. 269; on the colors of Felis
mitis, ii. 274; on the colors of Gervus
paludosus, ii. 276 ; on sexual differences
of color in Mycetes, ii. 277 ; on the color
of the infant Guaranys, ii. 303; on tho
early maturity of the female of Cebus
Azarw, ii. 303; on the beards of the
Guaranys, ii. 307 ; on the emotional notes
employed by monkeys, ii. 320: on Ameri-
can polygamous monkeys, ii. 846.
Representative species, of birds, ii. 1S2,
188.

Reproduction, unity of phenomena of,

throughout the mammalia, i. 13 ; period

of, in birds, ii. 205.
Reproductive system, rudimentary

structures in the, i.*29 ; accessory parts

of, i. 199.
Reptiles, ii. 26.

Reptiles and birds, alliance <>f. i. 804,
Resemblances, small, between man and

the apes, i. 184.
Retrievers, exercise of reasoning faculties

by, i. 46.

Revenue, manifested by animals, I. 39.
Reversion, i. 117; perhaps the cause of

some bad dispositions, i. 166.
Itluigittm, difference of color in the sexes

of a species of, i. 356.
Ramplumtos carinattts, ii. 217.
Rhinoceros, nakedness of, i. 143; horns

of, ii. 236; horns of, used defensively, ii.

251 ; attacking white or gray horses, ii.

SSL

Ilhyiu-hair, sexes and voting of, li. 193.
lihynduito AiMtrali^'W. 19:1.
iihynch<ra Henyitlvn*i*. ii. 193.
Illtyiu'Jura rapeiwi*, ii. 193.
KnvniM, perception of, by animals, ii. :!I7.
Km ii \iti>. M., on rudimentary muscles in
man, I. 19.

Richardson, Sir .1., on tho pairing of
'/•. Into uinbrUuM, ii. 46; on l,t,;i,> nr.,
ji/ianiuniiM, li. 56; on (he drumming of
grouse, ii. (1(1; on (he ilanees of fttnio
j>/i<t»i<iii?!/tiH, II. 66; on assemblages of

grouse, II. '.IT; oil (he billies of in.ilo

dear, H, 880; oa the rain dear, d, 888; on

the horns of tin i-W ox, ii. 280; on

antlers of (he rein. her, with BOrnSTOUl
points, il. 211 ; on the moose, ii 217.

Bion moaoM, on the Bootoh dear bound, ii

Ci* ii 1 1 a, .lean Paul, on Imagination, I. 44.
Ribdbl. on profligate Ibmus HffOH H
in.

426

INDEX.

E inc. -ouzel, colors and nidillcation of the,
ii. 162.

Ripa, Father, on the difficulty of distin-
guishing the races of the Chinese, i. 207.

Rivalry, in singing, between male birds,
ii. 60.

EiVER-noo, African, tusks and knobs of
the, ii. 254.

Rivers, analogy of, to islands, i. 196.

Roach, brightness of male during breeding-
season, ii. 18.

Robbery, of strangers, considered honor-
able, i. 90.

Robertson, Mr., remarks on the develop-
ment of the horns in the roebuck and
red-deer, i. 279.

Robin, pugnacity of the male, ii. 8S ; au-
tumn song of the, ii. 51 ; female, singing
of the, ii. 51 ; attacking other birds with
red in their plumage, ii. 106 ; young of
the, ii. 199.

Robin et, on the difference of size of the
male and female cocoons of the silk-
moth, i. 835.

Rodents, uterus in the, i. 118; absence of
secondary sexual characters In, 1. 259;
sexual differences in the colors of, ii. 272.

Roe, winter change of the, ii. 284.

Rolle, }■'.. on the origin of man, i. 4 ; on a
change in German families settled in
Georgia, i. 287.

Roller, ii. 53.

Romans, ancient, gladiatorial exhibitions of

the, i. 97.
Rook, voice of the, ii. 58.
Rossler, Dr., on the resemblance of the

lower surface of butterflies to the bark of

trees, i. 380.
Rostrum, sexual difference in the length

of, In some weevils, L 247.
Rudimentary organs, i. 17; origin of, i.

81.

Rudiments, presenco of, in languages, L
58.

EuDOLPnL on the want of connection be-
tween climate and the color of the skin,

i. 232.

Ruff, supposed to be polygamous, 1. 261 ;
proportion of the sexes in the, i. 297;
pugnacity of the, ii. 89, 44; double
moult in, ii. 78, 80 ; duration of dances of,

ii. 96 ; attraction of the, to bright objects,
ii. 107.

Ruminants, male, disappearance of canine
teeth in, i. 189 ; 11. 811 ; generally polyg-
amous, i. 258; analogy of LamelHcorn
beetles to, 1. 862; suborbital pita of, ii.
267; sexual differences of color in, ii.
274.

tiupicoln crocta^ display of plumage by
the male, ii. 88.

RCppell, on canine teeth in deer and an-
telopes, ii. 246.

Russia, numerical proportion of male and
female births in, i. 291.

Buticilla, ii. 172.

RC'timeyer, Prof., on the sexual differences
of monkeys, ii. 808.

Rutlandshire, numerical proportion of
male and female births in, i. 291.

S.

SAcns, Prof., on the behavior of the male
and female elements in fertilization, i.

265.

Sacrifices, Human, 1. 175.

Sagittal crest in male apes and Austra-
lians, ii. 804.

Sahara, birds of the, ii. 164; animal in-
habitants of the, ii. 214.

Sailors, growth of, delayed by conditions
of life, i. 110; long-sighted, i. 113.

Sailors and soldiers, difference in the pro-
portions of, i. 112.

St. John, Mr., on the attachment of mated
birds, 11. 104.

St. Kilda, beards of the inhabitants of; ii.
806.

Salmo erior, and S. nmhla, coloring of the
male, during the breeding-season, ii. 14.
Salmo Vycaodon^ ii. 4.
Salmo salar, ii. 4.

Salmon, leaping out of fresh water, i. 80 ;
male, ready to breed before the female,

i. 252 ; proportion of the sexes in, i. 299 ;
male, pugnacity of the, ii. 8 ; male, char-
acters of, during the breeding-season, ii.
8, 14; spawning of the, ii. lb; breeding
of immature male, ii. 206.

Salvin, O., on the Humming-birds, i. 260 ;

ii. 161 ; on the numerical proportion of
the sexes in Humming-birds, i. 298, ii.
212; on Chamcepete* and I'ewlope, ii.
61 ; on Sekuphonu plafyeerom, ii. 62 ;
on Pipra deliciosa, ii. 63 ; on Chasmo-
rhynchu*, 1L 76.

Samoa Islands, beardlessness of the natives

of, ii. 807, 888.
Sand-skipper, i. 328.

Sandwich Islands, variation in the skulls

of the natives of the, i. 105; superiority

of the nobles in the, ii. 640.
Sandwich Islanders, lice of, i. 211.
San Giuliano, women of, ii. 84i.
Santall recent rapid increase of the, i.

128: Mr. Hunter on the, i. 282.
SaphirincL, characters of the males of, i.

826.

Sarkidiorni* melon onotiut, characters of
the young, ii. 177.

Sars, Or on Pontoporeia nffini*, i. 819.

Saturnia carpini, attraction of males by
the female, t. 803.

Satumia Io, difference of coloration in the
sexes of, L 885.

Saturniid<&, coloration of the, i. 888, 88&

Savage, Dr., on the lighting of the male
gorillas, ii. 809 ; on the habits of the go-
rilla, ii. 846.

Savage and Wvman, on the polygamom
habit* of the gorilla, i. 258.

Savages, imitative faculties of, i. 55, 155;
causes of low morality of, i. 5«J; uniform
ity of, exaggerated, i. 107; long-sighted,

INDEX.

427

I. 113; rate of increase among, usually
small, i. 117 ; retention of the prehensile
power of the feet by, i. 136 ; tribes of,
supplanting one another, i. 154 ; improve-
ments in the arts among, i. 175 ; arts of,

i. 225 ; fondness of, for rough music, ii.
64; attention paid by, to personal ap-
pearance, ii. 322; relation of the sexes
among, ii. 847.

Saw-fly, pugnacity of a male, i. 353.
Saw-flies, propox-tions of the sexes in, i.
305.

Saxicola ncbicola, young of, ii. 210.

Scalp, motion of the, i. 20.

Scent-glands in snakes, ii. 28.

Schaaffhausen, Prof., on the develop-
ment ot the posterior molars in different
races of man, i. 26 ; on the jaw from La
Naulette, i. 122; on the correlation be-
tween muscularity and prominent supra-
orbital ridges, i. 126 ; on the mastoid pro-
cesses of man, i. 138 ; on modifications
of the cranial bones, i. 141; on human
sacrifices, i. 175 ; on the probable speedy
extermination of the anthropomorphous
apes, i. 193 ; on the ancient inhabitants
of Europe, i. 228 ; on the effects of use
and disuse of parts, i. 238 ; on the super-
ciliary ridge in man, ii. 301 ; on the ab-
sence of race-differences in the infant
skull in man, ii. 303 ; on ugliness, ii. 3ts7.

Sciiaum, II., on the elytra of Dytiiscm and
Hydroporw, i. 333.

Schelver, on dragon-flies, i. 352.

Schiodte, on the stridulation of Iletero-
cents, i. 368.

Schlegel, F. von, on the complexity of
the languages of uncivilized peoples, i.
59.

ScnLEOEL, Prof., on Tanyrdptera , ii. 182.

Schleicher, Prof., on the origin of lan-
guage, i. 54.

Sciileiden, Prof., on the rattlesnake, ii. 28.

Schomburgk, Sir P., on the pugnacity of
the male musk-duck of Guiana, ii. 40;
on the courtship of Rupicola crocea, ii.
88.

Schoolcraft, Mr., on the difficulty of fash-
ioning stone implements, i. 183.

Solatkr, P. L., on modified secondary
wing-feathers in the males of J'i/tnt, ii.
62; on elongated feathers in night-jars, ii.
69; on the specieH ot Chawnarh/ynch/u^

ii. 70; on the plumage of I't'leiutnitH
onocrotatu*, 11. b2 ; on the plain tain-
euters, 11. 169; on the sexes and young
of Tudoma TaHeyata, il. 197; on the
colors of /.( mur iiHK-nfo, ii. 'JT7 ; on the

■tripei in asset, ii. 89 1.

Scolkcida, absence of secondary sexual

characters In, 1. 812.
goolopaat Jrituitu, tail-feathers of, ii. 61.

SoolopatB galUnago, drumming ol ii. 80.
Soolopeus JiuMfun*, tail-feathers of, n. fli.
8oobpcui motor, assemblies ot; IL 97.
Sootopass Wutotrti. sound produced by, ii.
til.

ScolytiiH, stimulation of, I. 36S.

Scoter-duck, black, sexual difference in
coloration of the, ii. 216; bright beak of
male, ii. 217.

Scott, J., on the color of the beard in man,
ii. 304.

Scrope, on the pugnacity of the male salm-
on, ii. 3 ; on the battles of stags, ii. 229.

Sctjdder, 8. H., imitation of the stimu-
lation of the Orthoptera, i. 343 ; on the
stridulation of the Acridiidm, i. 846 ; on
a Devonian insect, i. 349 ; on stridulation,
ii. 315.

Sculpture, expression of the ideal of beau-
ty by, ii. 333.

Sea- anemones, bright colors of, i. 313.

Sea-bear, polygamous, i. 260.

Sea-elephant, male, structure of the nose
of the, ii. 264 ; polygamous, i. 260.

Sea-lion, polygamous, i. 260.

Seal, bladder-nose, ii. 265.

Seals, their sentinels generally female's, i. •
71 ; evidence furnished by, on classifica-
tion, i. 183 ; sexual differences in the col-
oration of, ii. 273 ; appreciation of music
by, ii. 317 ; battles of male, ii. 229 ; ca-
nine teeth of male, ii. 230 ; polygamous
habits of, i. 260 ; pairing of, ii. 257 ; sex-
ual peculiarities of, ii. 264.

Sea-scorpion, sexual differences in, ii. 9.

Season, changes of color in birds, in ac-
cordance with the, ii. 77 ; changes of plu-
mage of birds in relation to, ii. 172.

Seasons, inheritance at corresponding, i.
273.

Sebituant, ii. 324.

Sebright Bantam, i. 2S5.

Secondary sexual characters, i. 245 ; rela-
tions of polygamy to, i. 257; gradation
of, in birds, ii. 129 ; transmitted through
both sexes, i. 270.

Sedgwick, "W., on hereditary tendency to
produce twins, 1. 128.

Seemann, Dr., on the different appreciation
of music by different peoples, ii. 31S; on
the effects of music, ii. 820.

&l(ix]>horu* pfatyvercutt, acuminate first
primary of the male, ii. 62.

Selby, P. J., on the habits of the black
and red grouse, i. 260.

Selection, double, i. 267.

Selection of male by female birds, ii. 95,
117.

Selection, methodical, of Prussian grena-
diers, i. 108.

Selection, sexual, influence of, on the col-
oring of Lepidoptera, i. 890; explanation

ot; i. M8, Bra, MB.
Bbudoxxov, sexual and natural, oon treated.

i. 270.

Sei.k-cmmmanp, habit of, Inherited, I. 8^;

estimation of i. 91.
Sr.i 1 OOHACXOI OTBS, 1. 60.

Bm-raaaro mow, instinct of. 1. sv

Bau IA( 1:1111 1., l.v Mtagtf, 1. M ; estima-
tion of, i. 91.
Si mii 1 s m: Ibid, i. Mi

tSr»inof>it/irciiA, i. 1*9; long hair on th#
heads of speciia of, i. ls|, ||. 303.

INDEX.

Semnopithtcu* chryfiomrtas, sexual differ-
ences of color in, ii. 277.

Semnopithecm COflUtiBt, ornamental hair
on the head of, ii. 291.

Semtiopithecun frontatw, bcaid, etc., of,
ii. 294.

Semnopitheom naswa, nose of, i. 1S4.
Semnopithecus nemceus, coloring of, ii.
206.

Semnopithecm ruhiennrfus, ornamental

hair on the head of. ii. 801.
Senses, inferiority of Europeans to savages

in 111.-, i. 114.
Sf.ntinels, i. 71, 79.

Serpents, instinctively dreaded by apes
and monkeys, i. 86, 41.

terramis, hermaphroditism in, i. 200.

Sex, inheritance limited by, i. 273.

Sexes, relative proportions of, in man, i.
291, ii. 305 ; probable relation of the, in
primeval man, ii. 846.

Sexual characters, secondary, i. 245 ; rela-
tions of polygamy to, i. 259 ; transmitted
through both sexes, i. 270 ; gradation of,
in birds, ii. 129.

Sexual and natural selection, contrasted,

i. 269.

Sexual characters, effects of the loss of, i.
275 ; limitation of, i. 275.

Sexual differences in man, i. 14.

Sexual selection, explanation of, i. 249,
252, 262 ; influence of, on the coloring of
Lepidoptera, i. 890 ; action of, in man-
kind, ii. 852.

Sexual similarity, i. 268.

Sharks, prehensile organs of male, ii. 1.

Shari-e, K. Ii., on Tanyxiptera xylria, ii.
157; on Ceryle, ii. 165; on the young
male of Dacelo Oaudichaudi, ii. 180.

Siiaw, Mr., on the pugnacity of the male
salmon, ii. 8.

Shaw, J., on the decorations of birds,

ii. 68.

Sukep, danger-signals of. i. 74; sexual dif-
ferences in the horns of, i. 274 ; horns of,
i. 280 ; ii. 285, 247 ; domestic, sexual dif-
ferences of, late developed, i. 288; nu-
merical proportion of the sexes in, i. 295;
mode of fighting of. ii. 23s ; arched fore-
heads of some, ii. 271.

Sheep, Merino, loss of horns in females of,
1. 275 ; horns of, i. 2S0.

Shells, difference in form of. in male and
female Gasteropoda, i. 815 ; beautiful
colors and shajR-s of, i. 816.

Shield-drake, pairing with a common
duck, ii. 109 ; New Zealand, sexes and
young of, ii. 197.

Shooter, J., on the Kaffres. II. 831 ; on the
marriage-customs of the Kaffres, ii. 357.

Shrew-mice, odor of. ii. 265.

Shrike, Drongo, ii. 171.

Shrikes, characters of young, ii. 177.

Sun K.\r.i>. \V. K.. on sexual differences in
the wings of Hymenoptera, i. 834.

Phvness of adorned male birds, ii. 93.

Sintioiiiiiiit, proportions of the sexes in. i.
805 ; dimorphism in males of, i. 303. .

Siam, proportion of male and female births
in, i. 298.

Siamese, general beardlessness of the, ii.

306 ; notions of beauty of the, ii. 329 ;

hairy family of, ii. 361.
Siebold, C. T., von, on the auditory ap

paratus of the Btridulant orthoptera, i.

348.

Sight, inheritance of long and short, i. 114.

Signal-cries of monkeys, i. 55.

Silk-motii, difference of size of the malo
and female cocoons of the, i. 836; pairing
of the, i. 888 ; male, fertilizing two or
three females, i. 398 ; proportion of the
sexes m, i. 300, 302 ; Ailantus, Prof. Ca-
ncstrinl, on the destruction of its larva?
by wasps, i. 802.

Simiadje, i. 187 ; their origin and divisions.
i.204.

Similarity, sexual, i. 268.

Singing of the Cicadas and Fulgoridav i

851 ; of tree-frogs, ii. 25 ; of birds, object

of the, ii. 50.
Sirenia, nakedness of, i. 142.
tfirex juvenciM, i. 854.
Siricidjs, difference of the sexes in, i. 354.
Siskin, ii. 81: pairing with a canarv, ii.

110.

Si tana, throat-pouch of the males of, ii
81,85.

Size, relative, of the sexes of insects, i. 835.
Skin, movement of the, i. 19 ; nakedness

of, in man, i. 142; color of the, i. 232.
Skin and hair, correlation of color of, i.

239.

Skull, variation of, in man, i. 104 ; cubic
contents of, no absolute test of intellect,

i. 140; Neanderthal, capacity of the, i.
140 ; causes of modification of the, i. 141 ;
difference of, in form and capacity, in dif-
ferent races of men, i. 208 ; variability of
the shape of the, i. 218; differences of, in
the sexes in man, ii. 302 ; artificial modi-
fications of the shape of, ii. 824.

Skunk, odor emitted by the, ii. 265.
Slavery, prevalence of, L 90 ; of women,

ii. 850.

Slaves, difference between those of field

and house, i. 2(37.
Smell, sense of, in man and animals, i. 28.
Smith, Adam, on the basis of sympathy,

i. 78.

Smith, Sir A., on the recognition of women
by male ("ynocejihali, i. 13; on an in-
stance of memory in a baboon, i. 43 ; on
the retention of their color by the Dutch
in South Africa, i. 233; on the polygamy
of the South African antelopes, i. 258 ;
on the proportion of the sexes in Kobw
tllij)nipryinnus, i. 296; on lUuupluil nit
caperutis, ii. 28; on South African lizards,

ii. 85; on fighting gnus, ii. 229; on the
horns of rhinoceroses, ii. 237; on the
fighting of lions, ii. 254: on the colors of
the Cape Eland, ii. 274 ; on the colors of
the gnu, ii. 275; on Hottentot notions of
beautv, ii. 329.

Smith, K, on the Cynipidaj and Tenthredr

INDEX.

429

nidae, i. 305 ; on the relative size of the
6exes of Aculeate Hymenoptera, i. 837 ;
on the difference between the sexes of
ants and bees, i. 354 ; on the stridulation
of Trox sabuloms, i. 369 ; on the strid-
ulation of Mononychm pseudaeori, i.
371.

Smynthurus hrteus, courtship of i. 338.
Bnakes, sexual differences of, ii. 23 ; male,

ardency of, ii. 29.
" Snarling muscles,11 i. 122.
Snipe, drumming of the. ii. 60 ; coloration

of the, ii. 216.
Snipe, painted, sexes and young of, ii.

193.

Snipe, solitary, assemblies of, ii. 97.
Snipes, arrival of male before the female,

i. 251 ; pugnacity of male, ii. 41 ; double

moult in, ii. 77.
Snow-goose, whiteness of the, ii. 218.
Social animals, affection of, for each other,

i. 73 ; defehce of, by the males, i. 79.
Sociability, the sense of duty connected

with, i. 68 ; impulse to, in animals, i. 76,
77 ; manifestations of, in man, i. 81 ; in-
stinct of in animals, i. 82, 83.

Sociality, probable, of primeval men, i.
149 ; influence of on the development of
the intellectual faculties, i. 154 ; origin of,
in man, i. 155.

Soldiers, American, measurements of, i.
108.

Soldiers and sailors, difference in the pro-
portions of, i. 110.

Solenostoma, bright colors and marsupial
sack of the females of ii. 21.

Song of male birds appreciated by their
females, 1. 61 ; want of in brilliant-
plumaged birds, ii. 90 ; of birds, ii. 156.

Sorex, odor of, ii. 266.

Sounds admired alike by man and ani-
mals, i. 62 ; produced by fishes, ii. 22 ;
produced by male frogs and toads, ii. 25;
mstrumentally produced by birds, ii. 61,
et seqq.

Spain, decadence of, i. 171.

tSii<ir<ixxu» smaragduluft, difference of
color in the sexes of, i. 828.

Sparrow, pugnacity of the male, ii. 88;
acquisition of the Linnet's song by a, ii.
52; coloration of the, ii. 139 ; Immature
plumage of the, ii. 180.

Sparrow, white-crowned, young of the,

ii. 208.

Bf w:ko\\ h, house- and tree-, ii. 162.
Hi'Arrowb, new mates found by, ii. 101.
Si'ARRows, sexes and young "of, ii, 208;

learning to sing, il. 319.
Spathmra UndtrwoodA^ ii. 74.
Spawning of fishes, il. 15, 18.
Hi'KAit, origin Of the, i. 225.
Sl'KCiKH, cuuscs of the ud vancemcnt of, I.

105; distinctive oharaoten of, i. 806; or

MM Of Mian, i. 209; sterility and (util-
ity of, when crossed, I. 214 ; supposed,

ot man, i. 21*; gradation of, I. Bis: <iitii-
enity of defining. L 219 j repraientaUve,
of blrdg, II. 1*2, 1*3; of birds, compara-

tive differences between the sexes of dis-
tinct, ii. 184.
Spectre-insects, mimicry of leaves by, i.
401.

Spectrum femoratum, difference of color
in the sexes of, i. 350.

Speech, connection between the brain and
the faculty of, i. 56.

" Spel 11 of the black-cock, ii. 58.

Spencer, Herbert, on the dawn of intelli-
gence, i. 36 ; on the origin of the belief in
spiritual agencies, i. 63 ; on the origin of
the moral sense, i.>97; on the influence
of food on the size of the jaws, i. 113 ; on
the ratio between individuation and gene-
sis, i. 310 ; on music, ii. 820.

Sperm-whales, battles of male, ii. 229.

Spuingid^, coloration of the, i. 383.

Sphinx, Humming-bird, i. 387.

Sphinx, Mr. Bates on the caterpillar of a,

i. 402.

Spiders, i. 327 ; male, more active than fe-
male, i. 263 ; proportion of the sexes in, i.
306; male, small size of, i. 328.

Spilo8orna menthrasti. rejected by tur-
keys, i. 386.

Spine, alteration of, to suit the erect atti-
tude of man, i. 138.

Spirits, fondness of monkeys for, i. 12.

Spiritual agencies, belief in, almost uni-
versal, i. 62.

Spoonbill, ii. 57 ; Chinese, change of plu-
mage in, ii. 171.

Spots, retained throughout groups of birds,

ii. 126 ; disappearance of, in adult mam-
mals, ii. 288.

Spuengel, C. K., on the sexuality of plants,
i. 252.

Spring -boo, horns of the, ii. 239.

Sproat, Mr., on the extinction of savages
in Vancouver Island, i. 230; on the eradi-
cation of facial hair by the natives of Van-
couver Island, ii. 332; on the eradication
of the beard by the Indians of Vancouver
Island, ii. 363.

Spurs, occurrence of, in female fowls, i,
271, 275; development of in various spe-
cies of l'hasianida', I. 281 ; of Gallinaceous
birds, ii. 41, 43; development of, in fe-
male Gallinuceu', ii. 155.

Sjitil/a, different colors of the sexes of a
species of, i. 326.

HyuiRUKLS, battles of male. ii. 228: African,
sexual differences in the coloring of, ii.
272; black, ii. 2 mi.

Stacj, long hairs of the throat of. ii. 256;
horns of the, i. 270, 278; buttles of, ii.
229; horns of the, w ith numerous branch
es, II. 2-11 ; bellowing of the, il. 261 ; crest
of the, ii. 26s.

Stag-iikktlk, large size of male, I. 886:
weapons of the male, i. 804; numerical
proportion of sexes of i. 805.

Si ain i'on, 11. 'I'., on the numerical propor-
tion <>f the ItMl in the smaller mollis, i

808; habits* of Mtaekitta rqfltokmwk i

BOB j on the coloration of moths. L 884
on the rejootion of frhffaapwq nunt/mit;

430

INDEX.

ti, by turkcvs, L 8SG; on the sexes of

Affr'otis exclamotionit, i. 8t>6.
Stallion, mane of the, ii. 256.
Stallions, two. attacking a third, i. 72;

fighting, ii. 230; small canine teeth of, ii.

246.

Stansbury, Captain, observations on peli-
cans, i. 74.

Staphylinid.e, hornlike processes in male,
1.868.

Starfishes, bright colors of some, I. 813.

Stark, Dr., on the death-rate in towns and
rural districts, i. 169*; on the influence of
marriage on mortality, i. 170 ; on the high-
er mortality of males in Scotland, L 292.

Star lino, American field, pugnacity of
male, ii. 49.

Starling, red-winged, selection of a mate
by the female, ii. 111.

Starlings, three, frequenting the same
nest, i. 269, ii. 102 ; new mates found by,
ii. 101.

Statues, Greek, Egyptian, Assyrian, etc.,
contrasted, ii. 833.

Stature, dependence of, upon local influ-
ences, i. 110.

Staudinger, Dr., his list of Lepidoptera, i.
804 ; on breeding Lepidoptera, i. 803.

Staunton, Sir G., hatred of indecency a
modern virtue, i. 92.

Stealing of bright objects by birds, ii.
107.

Stebbing, T. R., on the nakedness of the

human body, ii. 859.
Stemmatopus, ii. 265.
iStenobothrus pratorum, stridulating or-

gans'of; i. 846.
Sterility, general, of sole daughters, i. 164 ;

when crossed, a distinctive character of

species, i. 206.
Sterna, seasonal change of plumage in, ii.

218.

Stickle-back, polygamous, i. 262; male,
courtship of the, "ii. 2 ; male, brilliant col-
oring of, during the breeding-season, ii.
14; nidiflcation of the, ii. 19.

Sticks used as implements and weapons
by monkeys, i. 50.

Sting in bees, i. 246.

Stokes, Captain, on the habits of the great

Bower-bird, ii. 66.
Stonechat, young of the, ii. 211.
Stone implements, difficulty of making, i.

188 ; as traces of extinct tribes, i. 228.
Stones, used by monkeys for breaking

hard fruits and as missiles, i. 134 ; piles

of, i. 224.

Stork, black, sexual differences in the bron-
chi of the, 11. 57; red beak of the, ii. 217.

Storks, ii. 216, 220; sexual difference ia
the color of the eyes of, ii. 128.

Strange, Mr., on the Satin Bower-bird, ii.
66.

Stbetcil, Mr., on the numerical proportion
in the sexes of chickens, i. 296.

Strepsiceros kudu, horns of, ii. 248; mark-
ings of, ii. 2S7.

Stridulation, by males of Theridion, i.

829 ; of the Orthoptera and Homoptera

discussed, i. 849 ; of beetles, i. 866.
Stripes, retained throughout groups of

birds, ii. 125; disappearance of, in adult

mammals, ii. 288.
Strisr. flammea, ii. 101.
Structure, existence of unserviceable

modifications of. i. 147.
Struggle for existence, in man, i. 174,

178.

Strutiterr, Dr.. on the occurrence of tho
supra-condyloid foramen in the humerus
of man, i. 27.

Stitmella ludoviciana, pugnacity of tho
male, ii. 48.

Sturnus vtdgaris^ ii. 101.

Subspecies, i. 219.

Suffering, in strangers, indifference of
savages to, i. 90.

Suicide, 1. 166; formerly not regarded as a
crime, i. 90 ; rarely practised among the
lowest savages, L 90.

SuiDiE, stripes of young, ii. 176.

Sumatra, compression of the nose by tho
Malays of, ii. 885.

Sumner, Archbishop, man alone capable of
progressive improvement, i. 47.

Sun-birds, nidiflcation of, ii. 161.

Superstitions, L 175; prevalence of, i. 95.

Superstitious customs, i. 66.

Superciliary ridge in man, ii. 801, 808.

Supebnumerary digits, more freqih nt in
men than in women, i. 268; inheritance
of, i. 276; early development of i. 29S.

Supra-condyloid foramen in the early pro-
genitors of man, i. 198.

Suspicion, prevalence of, among animals,
i. as.

Sultvan, Sir B. J., on two stallions attack-
ing a third, ii. 280.

Swallow-tail Butterfly, i. 881.

Swallows deserting their young, i. 80, 87.

Swan, black, red beak of the, ii. 217 ; black -
necked, ii. 220 ; white, young of, ii. 202 ;
wild, trachea of the, ii. 57.

Swans, 11. 216, 220; young, ii. 199.

Swaybland, Mr., on the arrival of migra-
tory birds, i. 251.

Swinhoe, R., on the common rat in For-
mosa and China, i. 49; on the sounds
produced by the male Hoopoe, ii. 60; on
Diorurus macrocercus and the Spoon-
bill, ii. 171 ; on the young of Ardtolay H.
182; on the habits of Tumir^ ii. 193; on
the habits of Ithynchaa BengaUnms, ii.
198; on Orioles breeding in immature
plumage, ii. 205, 206.

Sylria atricapilla. young of. H. 210.

Si/lrin cin, rt a, aerial love-dance of tho
male, 1L 65.

Sympathy, i. 162; among animals, L 74; its
supposed basis, L 78.

Sympathies, gradual widening of, i. 96.

SYNONATiiors fishes, abdominal pouch in
male, L 201.

Sypheotiile* auritus, acuminated prima-
ries of the male, ii. 62 ; ear-tufts of. 11

7a

INDEX.

431

T.

Tabantd^e, habits of; i. 246.
Tadorna variegata, sexes and young of,
ii. 197.

Tadorna vulpamer, ii. 109.
Tahitians, i. 176 ; compression of the nose
. by the, ii. 335.

Tail, rudimentary, occurrence of, in man,

i. 29 ; convoluted body in the extremity
of the, i. 29 ; absence of, in man and the
higher apes, i. 145, 187 ; variability of, in
species of Macacus and in baboons, i.
144 ; presence of, in the early progenitors
of man, i. 198 ; length of, in pheasants, ii.
149, 157, 158; difference of length of the,
in the two sexes of birds, ii. 157.

Tait, Lawson, on the effects of natural se-
lection on civilized nations, i. 1G2.

Tanagee, scarlet, variation in the male, ii.
121.

Tanagra cestiva, ii. 172; age of mature
plumage in, ii. 204.

Tanagra rubra, ii. 121 ; young of, ii. 210.

Tanais, absence of mouth in the males of
some species of, i. 247 ; relations of the
sexes in, i. 307 ; dimorphic males of a
species of, i. 319.

T anker ville, Earl, on the battles of wild-
bulls, ii. 229.

Tanyidptera, races of, determined from
adult males, ii. 182.

Tanyttiptera isylcia, long tail-feathers of,

ii. 157.

Taphroderes distortm, enlarged left man-
dible of the male, i. 334.

Tapirs, longitudinal stripes of young, ii.
176,288.

Tarsi, dilatation of front, in male beetles, i.
Tarsius, i. 192.

Tasmania, half-castes killed by the natives
of, i. 212.

Tattooing, i. 224 ; universality of, ii. 323.

Taste, in tho Quadrumana, ii. 282.

Taylor, G., on Quincalm major, i. 298.

Tea, fondness of monkeys for, i. 12.

Tkar-sacs, of ltuminants, ii. 267.

Teebay, Mr., on changes of plumage in
spangled Hamburg fowls, i. 272.

Teeth, rudimentary incisor, in ltuminants,
i. 17 ; posterior molar, in man, i. 25; wis-
dom, i. 26; diversity of, i. 104; canine, in
tho early progenitors of man, i. 198; ca-
nine, of male mammals, ii. 2:50; in man,
reduced by correlation, il. 810; Staining
of tho, il. 823; front, knocked out or tiled
by some savages, il. 321.

Tkuktmeikr, Mr., on tho abundance of
male pigeons, 1. 296; on the wattles of
game-cocks, u. 94; on the oourtahlp of
fowls, 11. 112; on dyed pigeon*, li. 118.

Tkmheta, il. 825.

Temper, In dogs and horses, Inherited, i.
88.

Tknoii, proportions of the MZei In the, L

2»9, 800; brightness of male, during
breeding-season, II. 18.

Tenebrionidjs, stridulation of, i. 367.

Tennent, Sir J. E., on the tusks of the
Ceylon Elephant, ii. 237, 247; on the fre-
quent absence of beard in the natives of
Ceylon, ii. 306 ; on the Chinese opinion of
the aspect of the Cingalese, ii. 328.

Tennyson, A., on the control of thought,

1. 91.

Tentheedinid^e, proportions of the sexes
in, i. 305 ; fighting habits of male, i. 353 ;
difference of the sexes in, i. 354.

Tephrodorni.% young of, ii. 182.

Teral, i. 229.

T ermites, habits of, i. 353.

Terns, white, ii. 218; and black, ii. 220.

Terns, seasonal change of plumage in, ii.
218

Terror, common action of, upon the lower

animals and man, i. 38.
Te-studo nigra, ii. 27.

Tetrao cupido, battles of, ii. 48; sexual
difference in the vocal organs of, ii. 53.

Tetrao phasianellux, dances of, ii. 65; du-
ration of dances of, ii. 96.

Tetrao Scoticun, ii. 163, 177, 186.

Tetrao tetrix, ii 103,177,186; pugnacity
of the male, ii. 42.

Tetrao umbellus, pairing of, ii. 46 ; battles
of, ii. 48 ; drumming of the male. ii. 59.

Tetrao urogalloiden, dances of. ii. 96.

Tetrao urogallm, pugnacity of the male,
ii. 42.

Tetrao urophaxianus, inflation of the

oesophagus in the male, ii. 55.
Thamnobia, young of, ii. 182.
Thaumalea picta, display of plumage by

the male, ii. 85.
Theda, sexual differences of coloring in

species of i. 377.
Thecla rubi, protective coloring of. i. 880.
Theridion, i. 329; stridulation of males

of, i. 331.

Theridion lineatum, variability of. i. 328.

ThomiHUH citreiM, and T. jlorU-otenK dif-
ference of color in the sexes of, i. 328.

Thompson, J. II., on tho battles of sperm-
whales, ii. 230.

Thompson, W., on the coloring of tho male
char during tho breeding-season, ii. 14;
on the pugnacity of tho males of HMM
nula ch/orojttt.i, ii. 89; on the (hiding of
new mates by magpies, ii. 99 ; on the
finding of new mates by l'crcgrine fal-
cons, ii. 100.

Tjihuax, processes of, in male beetles, i.
857.

Thorell, T., on the proportion of the
scves iii spiders, i 80(1.

Tbosvbaox, dlflnreuee in the teeth of the

two sexes of the, il. 6.
Thoughts, control of, i. 97.
Tkbvik, pairing with ■ bkokbird, ii. iin>;

colors ami nldllleutlon of the. ii. 162.
ThBUUDH, characters of voting, IL 177,

2. ".;.

'I'm u, his regrets, I. 91.

'I'm mii, kbeenee ot In ditlti and //y/<*

bate*, I. 136.

432

INDEX.

Thttbt, M_ on the numerical proportion of
male and female births among the Jews,
i. 202.

ThylacinuM, possession of the marsupial

sac by the male, i. 199.
Thybancra, L 888.

Tibia, dilated, of the male Ombro cri-

brariu*. L 888.
Tibia and femur, proportions of, In the

Aymara Indiana, L 115.
Tikrra del Fuego, marriage-customs ol, 11.

ML

Tioxr, colors and marking* of the, U. 2*7.
Timers, depopulation of districts by, In In*
dia, L 1 29.

Tillua elungntuK. difference of color in the

■exes of, L 85T.
Ti miiiity, variability of, hi the same sixties,

LM.

Twbka, proportion of the sexes In, L 801.

1 1 l-iil, i, pugnacity of male, i.

Tits, sexual difference of color in, li. loft.

Toads, 1L 84; male, treatment of ova by
some, I. 2i»2; male, reutlv to bret-d \n fore
tile female. I. 262.

T<o, lt. it. condition «-f. In the human em-
bryo, L 17.

Tomtit, blue, sexual difference of color in
the, 1L 166.

Tom; a Islands, heardlessness of the natives

of, U. 807, 888.
Toorr, Home, on Language, L 68.
Tools, dint, L 176; used by monkeys, L

49 ; use of, L 188.
Topknots, 1b birds, U. 71.

Ttnniru* rilhmu*, i»ro|M»rt i«»n of tile sexes
in, L 806.

Tortoise, voice of the male, 1L 816.

ToRTt'RRH, submitted to by American sav-
ages, 1. 91.

Ti>t>inuA, double moult in. il. 77.

Tot cans, colors and nl<litleati..n of the, ii.
168; beaks and ceres of the, II. 217.

Towns, residence in, a cause of diminished

stature, L 111.
Toynbrb, J., on the external shell of tho

ear in man, i. 21.
Tbachba, convoluted and embedded In the

sternum, hi some birds, il. 67 ; structure

of the, in Ilhynvhirii, ii. l'.»:i.
Trades, affecting the form of the skull, L

141.

Tl it{Jtlit/>lillM, Sexual difference* of color

in, IL 274.

Tr<n/ti<iji/tii* m-rij.tiiH. dorsal crest of. ii.
26» ; markings of, IL 286, 287.

Tbaoopab, L 261 ; swelling of the wattles
of the male, during courtship, IL 68 ; dis-
play of plumage by the male, IL 67;
markings of the sexes of the, IL 1£8.

7V>if/o/M ditpar, sexual difference in tho
color oC 11. 2$.

Ti: viMNt;. effect of. on tho mental differ-
ence between the sexes of man, IL 818.

Transfer of male characters to female
birds, li. 185. ■

Transmission, equal of ornamental char-
acters, to both sexes in mammals, 11. 238.

Traps, avoidance of, by animals, L 48 ; use

of, L 182.

Treachery, to comrades, avoidance of, by
savages, L 84.

Tremejr tutl tint fur, I. 854.

Tribes, extinct, i. 154; extinction of. L 226.

TrUliiiiM, difference of color in the sexes
of s species oC L 856.

Tkimkn, 1J„ on the proportion of the s, \. -
in Siuth African butterflies, i. 301 : on
tlx attraction nf males by the f. male of
/ <i*i,» <iiiij,h ijii, rruK i . otKt : on I'm u
iii<'i;i. i. :;»s; ,ni difference of color in
the sexes of beetles, L 856; on moths
brilliantly colored beneath. L 8)>4; on
uiimicry'in butterflies, L8S>8; on (ryna-
nimt /#**. and on the oceOated spots of
I^ pidopU ra, ii. 127; on Vylio Led<k, IL
128.

7Wm0«i, sexes and young of, IL 207.

Trinatt comuta, IL T8L

lrij,/,,iii,i. coloration of the species of. i.

a--.'.

Ti: i- 1 it a m. II. li.. on unhealthy districts In

North Africa, 1. 285; on the habits of the
chaffinch la Palestine, i. MS; on the

birds of the Sahara, ii. lt'4; on the ani-
mal- inhabiting th- -ahar.i. ii. 214.

TriUM erUiatuM, IL 28.

Tritxn jm/iiiij.rM, ii.

I'rituii i>u a, 1,itii*. ii. 23.

1 1 ,',//,;/ ;/f, m rulynri*. ii. 1 s{).

I k n-. : - and niditii ation of the. li.

168, 166.

Tkoi'd -biui>s, white only when mature, II.

218.

'1 itoi i, n. fn-Nh-water fishes of the. il. 17.
Tboct, proportion of the sexes in, i. 209 ;

mal< . i.ue-nacin ol the, ii. 8.
Trtxr milmioiuA, strldulation oC I 360.
Tumi, not rare between members of tho

same tribe, L 91; more highly appro

elated by certain tribes, I. 96.
Tvlloch, Major, on the Immunity of the

negro from certain fevers, L 984.
Tumbler, almond, change of plumage In

the, L 284.

Tun/iiM w,ml.i. ii. K,2; young of, ii. 2H>.

TurihiM miyrtitoritin, ii. 177.

Tun In* in ii*in-. ii. UVJ.

7'unlun polyglottiiA, young of, IL 210.

Tunlu* tonju,ifuA, ii. H>2.
Turkrt, swelling of the wattles of the
male, IL 68; variety of, with a toBkaot,
IL 71; recognition of a dog by a, 11. 106;
wild, pugnacity of young malt* ii. 40 ;
\n ild. i . 1 lies of 'ill- , ii. > : mule. wild, ac-
ceptable to domesticated females, ii. Ill :
wild, first advances made by older fe-
males, IL 118; wild, breast-tuft of bristles
ofthe,lL171.

Ti KKKV-ciK k. scraping of the wings of.
utM.n the ground, ii. .'>!• : wild, display of
plumage by, ii. isH ; lighting habits of, il.
94.

Tt km u. Prof. W.. on muscular fasciculi in
man referable to the panniculus earno-
sus, L 19 ; on the occurrence of the su-

4:13

I «mo Mat**, rate «f hat.— > to. L 1M;
afltj*t»cr of aatnraJ i iicOiM «* lh» prar ■

tai- 143,

I'uud dtoaaa of part*. HfcrU of L lit ;
Mmn o(«t^ nm of bm. L SsX

l'mn», rr»cr»k<o in titr. L 119; mar* or
Im drrided. la Um tan aajbfart, L 1 1 \
lift; douUr, in the ©arty progvtuvjr* of
L : . v

\ .

ww. I. 875; rfJpmMm
p of. to baric of trees. L
amlttt. oases of. L
Jofroas to that in the k
; of the races of man.
men than in women, L

38

«t i W |» art Ml •cV^W*. I f»T |
U lit; of aanaaaary artuai
A ML

Vtitnv i '.-»»u»#«l. i ft; *»»• . ' I

I • ii MMV L IT- . ***►<—-• L : ' .

II lg Ik li aft4raa.IL Tl.
Ttai.nnaa. *|»«t*a«aa*. I I ML
Vtiintav al—a r» aC »*l»**a twa »J-

.w. ntAoor. . ( (WV Aattaniwa*, L Hi.
V mm a* la aaiurr. i. M

Yaasoi*. ■■■■■ali*.4» U«»e*s Hi and
1. 11.

bnfitaiifi

J S *■* ■WPWi W<» << It M7
Yam a Mr. «a tha •«.<.* o of Ja|«oc««
■ MM HI 1 f
a. taatkar* ..f | ML

■tl. ML

Mi ij;"'k' t «L

t 144; .4* amir,* partly
to (W bady. L If.
t 4 i . 1 mmm ar%> of tW.

aC L

VaarWa r*W.if.v.i, tta
the strrwa, L M. Iff.
Yiaaiwa. r- - by

of plmty

■Jam ft. 17*
I Um mrUUir-U. L t*»
> n ikbnb. M . on tha In!

u|..ai!i!ur».l II"
Yiaaos. Aar. on the mala of Fpeira ni-

Viraa, ditVvrw of the arxea tai the 11 2H.
Vim, aa the number of .j^rVa of man. L

■a

YtBYrt* orifftaaDy aorial otdy, L 90 ; frad-
aal appreciati.* of. I

Via. «». rariablity <-L In man. L 103.

Vm Arrhlpeawro. population of the, L t!7.

\ i ii. I'r of, on tha JaohW-puUc

moadr, » lt2.

Veen muaie of bird*, ill-. g

Vocal arajaaa of man. L M: of Mrd*. L
K; tt. IM; of fW*r». IL 27; of the Inara-
aorra. ILM; dlffcrrttr* of. In theaexc* of
Ltd*. iL la ; primarily turd In rebtion to
the propagation of the stierie*. n. 81 ♦.

Voct. Carl on the oripin of specie*. L 1 j
on the orijrta of man. L 4; on the K-ml-
lunar fold In man. L 28; on thr- Imitative
Btcultiea of microcephalous idiots. L K ;
on microcephalous idiot*. L 116; on
•anna from Brazilian cave*. L 210; on
the eTolntJon of the race* of man. L 221 ;
on the formation of the skull in women,
iL 802; on the Amos and neproea. iL
806; on the increased cranial difference
of the sexes in man with ntcr--dev<-loj,-
ment IL 814; on the obliquity of the
ere in the Chinese and Japanese, ii. 0B&

434

INDEX.

Voice in mammals, ii. 261 ; in monkeys
and man, ii. 304; in man, ii. 319; origin
of; in air-breathing vertebrates, ii. 815.

Yon Baer, deiinition of advauceuicut in
the organic scale, i. 203.

Vulpian, Prof., on the resemblance be-
tween the brains of man and of the
higher apes. i. 11.

Vultures, selection of a mate by the fe-
male, ii. Ill ; colors of, ii. 219.

"Waders, young of, ii. 208.

Wagner, R.,on the occurrence of the dias-
tema in a Kaffre skull, i. 122; on the
bronchi of the black stork, ii. 57.

Wagtail, Ray's, arrival of the male before
the female, L, 251.

Wagtails, Indian, young of, ii. 1S2.

Waist, proportions of, in soldiers and sail-
ors, 1. 112.

Waitz, Prof., on the number of species of
man, L 218; on the color of Australian
infants, ii. 808; on the beardlessness of
negroes, ii. 806 ; on the fondness of man-
kind for ornaments, ii. 822 ; on the lia-
bility of negroes to tropical fevers after
residence in a cold climate, i, 284; on
negro ideas of female beauty, ii. 880 ; on
Javanese and Cochin-Chinese ideas of
lH'auty, ii. 881.

Walckenaer and Gervais, on the Myria-
iKMla, i. 830.

Waldeyer, M., on the hermaphroditism
of the vertebrate embryo, i. 199.

Wales, North, numerical proportion of
male and female births in, i. 291.

Walker, Alex., on the largo size of the
hands of laborers' children, i. 118.

Walker, F., on sexual differences in the
diptera, i. 838.

Wallace, Dr. A., on the prehensile use of
the tarsi in male moths, i. 248 ; on the
rearing of the Ailantus silk-moth. i.
802; on breeding Lepidoptera, i. 802;
proportion of sexes of Bonwyx Cynthia,
J',. yai/amau\ and 11. Pernyi, reared by,
i. 804; on the development of Bombyvo
Cynthia and B. yamamai, i. on
the pairing of Boaihyx Cynthia, i. 3:>i>;
on the fertilization of moths, 898.

Wallace, A. R., on the origin of man,
i. 4; on the power of imitation in man,
L 88; on the use of missiles by the
orang, L 50; on the varying apprecia-
tion of truth among different trilws,
1. 96; on the limits of natural selection
in man, i. 132, 152 ; on the occurrence of
remorse among savages, i. 159; on the
effects of natural selection on civilized
nations, L 161 ; on the use of the con-
vergence of the hair at the elbow in
the orang, L 185; on the contrast in
the characters of the Malays and Pa-
puans, i. 208; on the line of separation
between the Papuans and Malays, i. 210;
on the sexes of Omithoptera Cruww,
L 801; on protective resemblances, L
313 ; on the relative sizes of the sexes

of insects, 1. 836; on Elaphtvmyia, f.
888; on the Birds of Paradise, i. NO;
on the pugnacity of the males of /,<y>-
torhynchvs anamtattm, 1. 868; on
sounds produced by Ewhirns longi-
manus, i. 370; on the colors of J>ia-
dema, i. 876; on Kail i ma, i. 880;
on the protective coloring of moths,

i. 882; on bright coloration as protec-
tive in butterflies, L 383 ; on variability
in the Papilionida1, i. 889 ; on malo
and female butterflies inhabiting clin'er-
ent stations, i. 891 ; on the protective
nature of the dull coloring of female
butterflies, i. 392, 892, 401 ; on mimicry
in butterflies, i. 898; on the mimicry
of leaves by Phasmida\ i. 401 ; on the
bright colors of caterpillars, i. 403; on
brightly-colored fishes frequenting reefs,

ii. 17; on the coral snakes, ii. 80; on
Paradi*ea a pod a, ii. 70, 74; on the
display of plumage by male Birds of
Paradise, ii. 85; on assemblies of Birds
of Paradise, ii. 97; on the instability
of the oeellated spots in Ifipparchia
Janira, ii. 127; on sexually-limited in-
heritance, ii. 14S; on the sexual colora-
tion of birds, ii. 158, 187, 189, 192, 198 ;
on the relation between the colors
and nidiflcation of birds, ii. 158, 168;
on the coloration of the Cotingida-. ii.
169; on the females of J'aradisea
apoda and Papuana, ii. 184; on the
incubation of the Cassowary, ii. 1 95;
on protective coloration in birds, ii. 218 ;
on the hair of the Papuans, il. 829;
on the Babirusa, ii, 250; on the mark-
ings of the tiger, ii. 287 ; on the l>card8
of the Papuans, ii. 806; on the distribu-
tion of hair on the human body, ii. 259.

Walrus, development of the nictitating
membrane in the, 1. 28; tusks of the,
ii. 281, 287 ; use of the tusks by the, ii. 246.

Walsh, B. D., on the proportion of the
sexes in Papilio turnm, i. 801 ; on the
Cynipidaj and Cecidomyids, L 806; on
the jaws of Amtnophila, i. 882; on
Corydalis cornutus, i. 332; on the pre-
hensile organs of male insects, i. 888;
on the antenna) of J'entht, i. 838; on
the caudal appendages of dragon-flies,
i. :fcl4; on Platyphylhnn oaa-arinn,

i. :$4.">; on the sexes of the Kphcmcrkke,
1.850; on the difference of color in the
6cxcs of Sjtectrum femoratnm, i. 860;
on sexes of dragon-flies, i. 860; on the
difl'crcnee of the sexes in the Ichncu-
monidse, i. 864; on the sexes of Ormh
dticna atra, i. 857; on the variation
of the horns of the male Planum* car-
n ifrs, i. 359 ; on the coloration of the
species of Anthoehari*, i. 881.

Wapiti, battles of. ii. •.'•.'it; trues of horns
in the female, ii. 234 ; attacking a man,

ii. 241 ; crest of the male. ii. 26H; sexual
difference in the color of the, ii. 276.

Warbler, Hedge, ii. 189 ; young of the,
ii. 200.

Warm lees, Suporb, nidiflcation of, iL 161.

INDEX.

435

Wariness, acquired by animals, i. 48.

Warington, K., on the babits of the
sticklebacks, ii. 2, 20; on tbe brilliant
colors of the male stickleback during the
breeding-season, ii. 14.

Waet-hog, tusks and pads of the, ii. 253.

Watchmakers, 6hort-sighted, i. 113.

Waterhen, ii. 38.

Waterhouse, C. O., on blind beetles, i.

356 ; on difference of color in the sexes

of beetles, L 356.
Waterhouse, G. R., on the voice of Ilylo-

batea agilis, ii. 316.
Water-ouzel, autumn song of the, H. 51.
Waterton, C, on the pairing of a Canada

goose with a Bernicle gander, ii. 109 ; on

hares fighting, ii. 228 ; on the Bell-bird,

ii. 75.

Wattles, disadvantageous to male birds

in fighting, ii. 94.
Wealth, influence of, i. 1G3.
Weale, J. ManseL, on a South African

caterpillar, i. 403.
Weapons, employed 'by monkeys, i. 50;

use of, i. 132 ; offensive, of males, i. 249 ;

of mammals, ii. 230, et eeq.
Weaver-bibd, ii. 52.

Weaver-birds, rattling of the wings of,
ii. 59 ; assemblies of, ii. 97.
• Webb, Dr., on the wisdom teeth, i. 26.

Wedgewood, Ilensleigh, on the origin of
language, i. 54.

Weevils, sexual difference in length of
6nout .in some, i. 247.

Wkir, Harrison, on the numerical propor-
tion of the sexes in pigs and rabbits, i.
295; on the sexes of young pigeons, i.
297; on the songs of birds, ii. 50; on
pigeons, ii. 104; on the dislike of blue
pigeons to other colored varieties, ii. 113 ;
on the desertion of their mates by female
pigeons, il. 114.

Weir, J. Jcnner, on the nightingale and
blackcap, i. 257; on the relative sexual
maturity of male birds, i. 253 ; on female
pigeons deserting a feeble mate, i. 254 ;
on three starling frequenting the same
nest, i. 260; on tho proportion of the
sexes in Machetes pugvax and other
birds, i. 297 ; on tho coloration of the
T/ iji/twnai, i. 888; on the rejection of
certain caterpillars by birds, i. 403 ; on
sexual difference! or tbe beak in (ho
goldfinch, il. 8H; on a piping bullfinch, ii.
50; on tho object or the nightingale's
song, Ii. 49 ; on song-birds, ii. M ; on the
pugnacity of male llnc-plumaged birds,
11. H9; on tho conrtwhlp of birds, ii. 90;
on the finding of new mates by Pore-

grliio-falcoim and Kestrels, II. ion; on
the bullllnch and starling, IL lol ■ on the
cause of birds remaining unpaired, II.
108: on starlings and parrots living In
triplets, II. 108; on recognition of color

by birds, il. 106; on hybrid birds. U, 109;
on the selection of a greenfinch by a lb-

mi)*. canary, II. 110; on a ease of rl\ ah y

of teinaie bullfinches, ii. IH'> ; on the ma-
turity of the Cloldeii pheasant, II. 20-1.

Weisbach, Dr., measurement of men of
different races, i. 208; on the greater
variability of men than of women, i. 266 ;
on the relative proportions of the body
in the sexes of different races of man, ii.
305.

Welcker, M., on Brachycephaly and Do-
lichocephaly, i. 142 ; on sexual differences
in the skull in man, ii. 302.

Wells, Dr., on the immunity of colore!
races from certain poisons, L 234.

Westring, on the stridulation of Redtmius
personatus, i. 340; on the stridulating
organs of the Coleoptera, i. 370 ; on
sounds produced by Uychrus, i. 370 ; on
the stridulation of males of Theridion,
i. 330 ; on the stridulation of beetles, i.
367 ; on the stridulation of Omaloplia
bmnnea, i. 369.

Westphalia, greater proportion of female
illegitimate children in, i. 292.

Webtrop, H. M., on the prevalence of cer-
tain forms of ornamentation, i. 224.

Westwood, J. O., on the classification of
the Hymenoptera, i. 181 ; on the Culi-
cidae and Tabanidaj, i. 246 ; on a Hymen-
opterous parasite with a sedentary male,
i. 263 ; on the proportions of the sexes
in Z/ucanu8 cervus and Siagonitim, i.
805 ; on the absence of ocelli in femalo
mutillidae, i. 831; on tho jaws of Am-
mophila, i. 332 ; on the copulation of in-
sects of distinct species, i. 832 ; on tho
male of Cruhro cribrariw, i. 833; on
the pugnacity of malo Tipulce, i. 839 ; on
the stridulation of Pirates stridulus, i.
840 ; on the Cicada?, i. 341 ; on the strid-
ulating organs of tho crickets, i. 335; on
I'nevmora, i. 347 ; on Ephippiger riti-
m, i. 345, 34S; on the pugnacity of the
Mantides, i. 349; on J'hityblemnits* i.
850 ; on difference in tho sexes of the
Agrionido", i. 851 ; on tho pugnacity of
tho males of a species of Teuthredinie,
i. 852 ; on the pugnacity of the male
stag-beetle, i. 364; on JSltdtlt) taurun
and Siagotii mwi, i. 363 ; on lamellieorn
beetles, i. 864 ; on the coloration of I.itho-
Hia, i. 888.

Whale, Sperm-, battles of male, ii. 229.

Whales, nakedness of, i. 142.

Wiiatki.y, Archb., language not peculiar
to man, I. 52; on tho primitive civiliza-
tion of man, I. 174.

W nr. well, Prof, on maternal alVection,
I.8S.

Wfiia&JUt. in monkeys, 1. 1SS.
Winrr., Gilbert, on the proportion of tho
sexes in tho partridge, I. 2!i7 ; on tho

hooae cricket, i. Mfl : oo tbe object ..r

the song of birds, il. 50; on the finding
of new mates by white owls, II. lol ; on
spring coveys of male partridges. II. 108,

\YiiMiM-.s, a SeXUal ornament in IOQM
birds, II. 221 ; of mammals Inhabiting
snow \ countries, il. 2^4.

Wi iiiiat, aerial love-dance of the

male, IL Oft ■

\\ mow iiikh, pob, famous, I. 260; Inc. d

43G

INDEX:

ing plumago of the mule, H. 80, 03 ; fe-
male, rejecting the unadorned male, li.
115.

Widows and widowers, mortality of. 1.170.
Wig son, pairing with a pintail duck, iL
109.

Wilckens, Dr., on the modification of do-
mestic animals In mountainous regions,
i. 116; on a numerical relation between
the hairs and excretory pons in sheen,

i. •-':;;».

"Wilder, Dr. Burt, on the greater fre-
quency of supernumerary digits in men
than in women, L 267.

"Williams, on the marriage-customs of the
Fyisns, U. 857.

Wilson, Dr. on the conical heads of the
natives of Northwestern America, ii. 885;
on the Fijians, ii. 885 ; on the persistence
of the iashiou of compressing the skull

ii. 886.
Winc-si'it.s, ii. l.V>.

Winch, differences of. In the two sexes of
butterflies and Hymenoptera, i. 835 ;
play of, in the courtship of birds, II. 01.

Winter, change of color of mammals in,
11. 284.

Witchcraft, 1. 66.

Wives, traces of tho forcible capture of, L
175.

Wolf, winter change of the, II. 284.

Wolff, on the variability of the viscera in
man. i. In.*).

Wollabton, T. V, on Eurygnathvn, I.
884 ; on musical curculionida\ i. 866 ; on
the stridulation of AoalU*, L 872.

Wolves learning to bark from dogs, L 42 ;
hunting in packs, L 72.

Wolves, black, ii. 280.

W..MHAT. blaek varieties of the. ii. 2*0.

Women distinguished from men by male
monkeys, L 18 ; preponderance of, in
numbers, I. 202 ; effects of selection of,
in accordance with different standards
of beauty, iL 830 ; practice of capturing,
li. 844, 848 ; early betrothals and slavery
of, ii. 850; selection of, for beanty, ii.
856 ; freedom of selection by, in savage
tribes, H. 856.

Wonder, manifestations of, by animals, 1.41.

Wonfor, Mr., on sexual j>eeullarities in the
wings of butterflies, i. 885.

Woolner, Mr., observations on the ear in
man, i. 22.

Wood, J. on muscular variations in man,
L 105, 128, 124 ; on the greater variability
of the muscles in men than in women, L
'.66.

Wood, T. W. on the coloring of the onmpe-
tlp butterfly, L 881 ; on the habits of the
Baturnlkue,- i- 885 : on the habits of Me-
nura Albert^ iL 58; on Tetrao eupido,
ii. 58 ; on the display of plumage by male
pheasants, iL 85; on the ocellated spots
of the Argus pheasant, ii. 188; on the
habits or the female Cassowary, iL 195.

Woodcock, coloration of the, U. 216.

Woodpecker, selection of a mate by the
female, iL 111.

Woodpeckers, II. 53; tapping of, II. 50;
c<»lur» and nldification of the. ii. 163, l»Kl,
214; characters of young, ii. 177. 100, '.'00.

Worm ald, Mr., on the coloration of V/yy/o-
I'l/rn, i. :Ki.

WofNDK. healing of. i. 13.

Wren, IL 189 ; young of the, II. 200.

Wright, C. A, on the young of OroceUt
and I'ttrocincla, li. 210.

Wright, Chauncey, on correlative acquisi-
tion, ii. 819 ; on the enlargement of the
bruin in man, li. 873.

Wright, Mr., on the Scotch deerhound. IL
250; on sexual preference In dogs, IL 259 ;
on the rejection of a horse by a mare, iL
260.

WRiGirr, W. von, on the protective plu-
mage of the Ptarmigan, ii. Is.
Writing, 1. 175.

Wtman, Prof., on the prolongation of the

coccyx in the human embryo, 1.16; on
the condition of the great-toe in the hu-
man embryo, L 17; on variation in the
skulls of the natives of the Sandwich
Islands, I. l'U; on the hatching of the
cirirs in tin- moiith> and branchial cavities
of male llshcs, L Ml; iL 19.

X.

XENARcirra, on the Cicadas, t. 840.

A< norhi/mhii*, sexual diff< rence in the col-
or of the eyes in, ii. 128.

SVi/>hoj'fi<>rim //<7/« / <7, peculiar anal fin of
the male. ii. 0. 10.

XylocopO) difference of the sexes in, I. 354.

Y.

Yarrell, W., on the habits of the Cvprl-
nida?, i. 800; on liai.i , /<n;it,i. 11.2; on
the characters of the male salmon during
the breeding-season. iL 4, 14 ; on the char-
actors of the rays, iL 6; on the gemme-
ous dragonet, ii." 8; on the spawning of
the salmon, iL 18 ; on the incubation of
the Lophobranchil, iL 20; on rivalrv in
song-birds, ii. 50; on the trachea of the.
swan, iL 57; on the moulting of the ana-
tiche, 11. 81 ; on an instance of i iMMWilm
In a gufl, iL 104; on the young of the
waders, ii. 208.

Yellow fever, Immnnity of negroes and
mulattocs from, i. 234.

You ATT, Mr. on the development of the
horns in cattle, I. 280.

Ycra-caras, their notions of beauty, I.
881.

Z.

Zebra, rejection of an ass by a female, iL

281 ; stripes of the, 11. 288.
Zehcs, bnmps of, iL 271.
Zigzags, prevalence of, as ornaments. I. 221.
Zinckr, Mr., on European emigration to

America, L 172.
Zootttca ririparO) sexual difference in the

color of, iL 84.
Ztg j-nidje, coloration of the, L 8S8.

WOKKS OF HEEBERT SPEXCEB,

PUBLISHED BY

D. APPLETON AND COMPANY.

SYSTEM OF PHILOSOPHY

I.— FIRST PRINCIPLES.
{New and Enlarged Edition.)
Part I. — Tiie Unknowable.
Part II.— Laws of the Knowable.

659 pages. Price, $2.50

II.— THE PRINCIPLES OF BIOLOGY. — VOL. L
Part I. — The Data of Biology.
Part II. — The Inductions of Biology.
Part III. — The Evolution of Life.

475 pages. Price, $2.50

PRINCIPLES OF BIOLOGY.— VOL. II.
Part IV. — Morphological Development.
Part V. — Physiological Development.
Part VI. — Laws of Multiplication.

565 pages. Price, $2.50

III.— THE PRINCIPLES OF PSYCHOLOGY.

Part L — Tiie Data of Psychology. 144 pages. Price, - . $0.75

Part IL — The Inductions of Psychology. 140 pages. Price, - $0.75
Part III. — General Synthesis. 100 pages. ) „ .

Part IV.— Special Synthesis. 112 pages. \ 1 nce> " "

MISCELLANEOUS.

I.— ILLUSTRATIONS OF UNIVERSAL PROGRESS.
Thirteen Articles. 451 pages. Price, .... - $'2.50

I L— ESSAYS :
Moral, Political, and Av.nnr.ric.
Ten Essays. 380 pages. Price, $2.50

JIT— SOCIAL STATICS:
Or tiik Conditions Essential to Human Happiness Specified, and tiik

First of them Developed.

5(23 pages. Price, $2.50

IV.— EDUCATION':
Intellectual, Moral, and Physical.

488 pngeft. Frier, $1.25

V.— CLASSIFICATION OF TIIK SCIKNCKS.

50 pa^cs. Frier, ... . ..... $0.28

VI.— SPONTANKOI S GENERATION, 4<«.

.6 pageH Prlco, . ... I" .'3

THE ORIGIN OE CIVILIZATION;

OR, TUB

PRIMITIVE CONDITION OF MAN
By SIR JOHN LUBBOCK, Bart, M. P., F. R. S.

3SO Tages. Illustrated.

This interesting work is the fruit of many years' research
by an accomplished naturalist, and one well trained in mod-
ern scientific methods, into the mental, moral, and social con-
dition of the lowest savage races. The want of a work of
this kind had long been felt, and, as scientific methods aro
being more and more applied to questions of humanity, there
has been increasing need of a careful and authentic work de-
scribing the conditions of those tribes of men who arc lowest
in the scale of development.

"This interesting work — for it is intensely so in its aim, scope, and the
ability of its author — treats of what tho scientists denominate anthropology,
or the natural history of the human species ; the complete science of man,
body and soul, including sex, temperament, race, civilization, etc." — Provi-
dence Pre**.

"A work which is most comprehensive in it.s aim, and most admirable in
its execution. The patience and judgment bestowed on the book arc every-
where apparent ; the mere list of authorities quoted giving evidence of wide
and impartial reading. The work, indeed, is not only a valuable one on ac-
count of the opinions it expresses, but it is also most serviceable as a book
of reference. It offers an able and exhaustive table of a vast array of facts,
which no single student could well obtain for himself, and it has not been
made the vehicle for any special pleading on the part of the author." —
London Alhenorum.

u The book is no cursory and superficial review; it goes to the very heart
of the subject, and embodies the results of all the later investigations. It is
replete with curious and quaint information presented in a compact, luminous,
and entertaining form." — Albany Evening Journal.

" The treatment of the subject is eminently practical, dealing more with
fact than theory, or perhaps it will be more just to say, dealing only with
theory amply sustained by fact." — Detroit Free Press.

"This interesting and valuable volume illustrates, to some extent, the
way in which the modern scientific spirit manages to extract a considerable
treasure from the chaff and refuse neglected or thrown aside by former in
quirers." — Ixmdon Saturday Review.

D. APPLETON & CO., Publishers.

SPENCERS SYSTEM OF PHILOSOPHY,

THE PHILOSOPHY OF EY0LUT10N.

By HERBERT SPENCER.

This great system of scientific thought, the most original and important men-
tal undertaking of the age, to which Mr. Spencer has devoted his life, is now well
advanced, the published volumes being: First Principles, The Principles of Bi-
olo>pj, two volumes, and The Principles of Psychology, vol. L, which will be
shortly printed.

This philosophical system differs from all its predecessors in being solidly
based on the sciences of observation and induction ; in representing the order
and course of Nature ; in bringing Nature and man, life, mind, and society, under
one great law of action ; and in developing a method of thought which may serve
for practical guidance in dealing with the affairs of life. That Mr. Spencer is the
man for this great work will be evident.from the following statements :

" The only complete and systematic statement of the doctrine of Evolution
with which I am acquainted is that contained in Mr. Ilerbert Spencer's 1 System
of Philosophy;' a work which should be carefully studied by all who desire to
know whither scientific thought is tending."— T. II. Huxley.

" Of all our thinkers, he is the one who has formed to himself the largest new
scheme of a systematic philosophy." — Prof. Masson.

"If any individual influence is visibly encroaching on Mills in this country, it
is his." — Ibid.

"Mr. Spencer iB one of the most vigorous as well as boldest thinkers that
English speculation has yet produced." — John Stuaut Mill.

M One of the acutest metaphysicians of modern times."— Ibid.

" One of our deepest thinkers."— Dr. Joseph D. Hooker.

It la questionable If any thinker of finer calibre has appoarod in our coun
try.11— QEonoE Henry Lkwes.

"He alone, of all British thinkers, has organized a philosophy."— Rid.

" Ho Is as keen an analyst as is known In the history of philosophy ; I do not
except cither Aristotle or Kant."— Ueokoe Uii'lkt.

"If wo wcro to glvo our own Judgment, wo should say that, since Newton,
there has not In England been a philosopher of more remarkable spin illative and
•ystamatlzing talent than (in spite or some errors and somo narrownem) Mr. Her-
bert Bpoucer."— London Saturday lieview.

uWo cannot refrain from offering oar tribute of respect to one who, whether
tor loo extent of his pohltlvo knowledge, or for the profundity of hi* speculative
Insight, has already achieved * namo Hcrond to none In tlie wliole r;m «. .»f Kn^-
Hsh philosophy, and whoso works will worthily sustain the credit i.f RuJIafi
thought in the present gonoratlou."- Wettmin-dr Uti+ev.

Woifo of Ilcrbcrt Spencer pullieJied by D. Appldon & CV.

A NEW SYSTEM OF PHILOSOPHY.

FIRST PRINCIPLES.

& VoL I*rge 12mo. 615 Pases. Price $2 50.

Contents:
Taut Fikst. — Tlu Unknowable.

Ciiaptci i. Religion and Science; II. Ultimate Religious Ideas; III
Ultimate Scientific Ideas; IV. The Relativity of all Knowledge; V The
Reconciliation.

Paiit Secono — Lares of the Knoxeallc.

L Laws in General; IL The Law of Evolution; III. The same con-
tinued; IV. The Causes of Evolution; V. Space, Time, Matter, Motion, and
Force ; VL The Indestructibility of Matter ; VII. The Continuity of Motion ;
VHL The Persistence of Force ; IX. The Correlation and Equivalence of
Forces; X. The Direction of Motion ; XL The Rhythm of Motion ; XII. The
Conditions Essential to Evolution ; XIII. The Instability of the Homoge-
neous ; XIV. The Multiplication of Effects ; XV. Differentiation ^nd Inte-
gration ; XVL Equilibration ; XVIL Summary and Conclusion.

In the first part of this work Mr. Spencer defines the province, limits, and
relations of religion and science, and determines the legitimate scope of
philosophy.

In part second he unfolds those fundamental principles which have been
arrived at within the sphere of the knowable ; which arc true of all orders
of phenonema, and thus constitute the foundation of all philosophy. The
law of Evolution, Mr. Spencer maintains to be universal, and he has hers
worked it out as the basis of his system.

These First Principles are the foundation of a system of Philosophy
bolder, more elaborate, aud comprehensive perhaps, than any other which
nai been hitherto designed in England. — British Quarterly Eetiew.

A work lofty in aim and remarkable in execution — CorrJiill Magazine.

In the works of Herbert Spencer we have the rudiments of a positive
Theology, and an immense step toward the perfection of the science of Psy-
chology.— Christian Examiner.

If we mistake not, in spite of the very negative character of his own re»
■nits, he has foreshadowed some strong arguments for the doctrine of a posi-
tive Christian Theology. — New En g hinder.

As far as the frontiers of knowledge, where the Intellect may go, there H
to living man whose guidance may more safely be trusted. — AtlamM*

Worte of Herbert Spencer published by D. Appleton & Co.

Ia One Volume, 8vo., Cloth. Price $3.50.

SOCIAL STATICS;

OB,

THE CONDITIONS ESSENTIAL TO HUMAN HAPPINESS SPECI*
FIED, AND THE FIEST OF THEM DEVELOPED.

BY HERBERT SPENCER.

OPINIONS OF THE PRESS.

Mr. Spencer, in Lis able and logical work on 11 Social Statics " . . . . Edin'
burgh Review.

It deserves very high praise for the ability, clearness, and force with which
it is written, and which entitle it to the character, now so rare, of a really sub-
stantial book. — North British Review.

A remarkable work. .... Mr. Spencer exhibits, and exhibits with re-
markable force and clearness, many sociai equalizations of a just and right
species which remain yet to bo effected. — BHtUh Quarterly Review.

An inquiry conducted throughout with clearness, good temper, and strict

login We shall be mistaken if this book do not assist in organising that

huge mass of thought which, for want of a more specific name, is now called
Liberal Opinion.— Athenaeum.

It Is the most eloquent, the most Interesting, the most clearly-expressed and
logically-reasoned work, with views the most original, that has appeared in the
science of social polity. — Literary Gazette.

The author of the present work is no ordinary thinker, and no ordinary wri-
ter; and ho gives us, in language that sparkles with beauties, and in HMQIllH
at onco novel and elaborate, precise and logical, a very comprehensive and

complete exposition of tho rights of men In society The book will

mark an epoch In tho literature of scientific morality.— Evonom'iHt.

Wo remember no work mi ethics since that of Spinoza to be compared with
It In tho simplicity of Its premises, and tho logical rigour will, w hi, h :i com-
plete system of scientific ethics Is evolved from them \ work at one

so sfllmitlnc In spirit and method, and so popular in execution, we shall look in
vain for through libraries of political philosophy.— Leader.

Tho careful reading wo havo given If has botk uto-rd. d u* Int. n-.- pleasure,
and rendered It a duty to express, with unusual emphasis, our opinion of ita
l-rval ability and excellence.— Xotu-on/<>nni.sL.

Nkw YOUCI I). Arn.rroN and OoMPAVT.

Work$ of Herbert Spencer published by D. Applttcn dt Co.

The Philosophy of Herbert Spencer.

THE

PRINCIPLES OF BIOLOGY

VoL L 475 pa<?es. (Now in press.)

CONTENTS:

Part I. — The Data op Biology.

L Organic Matter. — EL The actions of Forces on Organic Matter.— ITT. Tb«
re-actions of Organic Matter on Forces. — IV. Proximate Definition of
Life. — V. The Correspondence between Life and its Circumstances. —

VI. The Degree of Life varies as the Degree of Correspondence.—

VII. The Scope of Biology.

Part II. — The Inductions op Biologt.

L Growth. — II. Development. — III. Function. — IV. Waste and Repair. —
V. Adaptation. — VI. Individuality. — VII. Genesis. — VIII. Heredity. —

IX. Variation. — X. Genesis, Heredity, and Variation. — XI. Classifica-
tion.—XII. Distribution.

Part HI. — The Evolution op Lira.

L Preliminary. — n. General Aspects of the Special-creation-hypothesis. —
III. General Aspects of the Evolution-hypothesis. — IV. The Arguments
from Classification. — V. The Arguments from Embryology. — VI. The
Arguments from Morphology. — VII. The Arguments from Distribution,
— VHX How is Organic Evolution caused ? — IX. External Factors.—

X. Internal Factors. — XI. Direct Equilibration. — XII. Indirect Equili
bration.— XIII. The Cooperation of the Factors.— XrV. The Converg
encc of the Evidences.

All these works are rich In materials for forming Intelligent opinions, even where
we arc unable to agree with those put forth by the author. Much may be learned from
Jiem In departments In which our common Educational system la very deficient The
actiro citizen may derive from them accurate systematized Information concerning his
lUfhest duties to society, and the principles on which they aro based. He may gala
Skarer notions of the value and bearing of evidence, and be better able to distinguish
between (acta and Inferences. He may find common things suggestive of wiser thought
—nay, we will venture to say of truer emotion— than before. By giving us fuller reali-
sations of liberty and Justice his writings will tend to lnoreaae our self-reliance In the
great emergency of civilisation to which we have been summoned.— Atlantic JlontJUv

Work* published by D. Appleton <t Co.

THE CORRELATION AND CONSERVATION

OF

FORCES.

A SERIES OF EXPOSITIONS BY GROVE, MAYER, JIELMHOLTZ,
FARADAY, LIEBIG, AND CARPENTER.

WITH

AN INTRODUCTION.

BY E. L. YOUMAN3

The work embraces :

I. — THE CORRELATION OF FI1YSICAL FORCES. Bt
W. R. Ckove. (Tlio complete work.)

IT. — CELESTIAL DYNAMICS. By Dr. J. R. Mayr*.

III. — THE INTERACTION OF FORCES. Bi Pbot, IIklm-

nOLTZ.

IV. — THE CONNECTION AND EQUIVALENCE OF
FORCES. I*y Pbof. Li Kino.

V. — ON THE CONSERVATION OF FORCE. Br

Faraday.

VI. — ON THE CORRELATION OF TIIYSICAL AND VI
TAL FORCES. Ht Du. Ca icikntkr.

Works of Herbert Spencer publislitd by D. App don dk Ce.

ESSAYS:

MORAL, POLITICAL, AND ESTHETIC.

In one Volume. Large 12mo. 386 pajrea.

contents:
t The Philosophy of Style.
IL Over-Legislation.

III. Morals of Trade.

IV. Personal Beauty.

V. Representative Government.
VI Prison-Ethics.

VII. Railway Morals and Railway Policy.
VIIL Gracefulness.
IX. State Tamperings with Money and. Banks.
X. Reform ; the Dangers and the Safeguards.

■ These Essays form a new, and if we are not mistaken, a most popular Installment
of the intellectual benefactions of that earnest writer and profound philosopher, Her-
bert Spencer. There is a remarkable union of the speculative and practical in these
papers. They are the fruit of studies alike economical and psychological ; they touch
the problems of the passing hour, and they grasp truths of universal application ; they
will be founa as instructive to the general reader as interesting to political and social
•tudenta." — Boston Transcript

■ These Essays exhibit on a:most every page the powers of an independent human-
itarian thinker. Mr. Spencer's ethics are rigid, his political views liberalistic, and hi*
aim is the production ol the highest earthly good." — Methodist Quarterly Review.

w It abounds hi the results of the sharp observation, the wide reach of knowledge,
and the capacity to write clearly, forcibly, and pointedly, for which this writei Is pre-
eminent The subjects are all such a.s concern us most intimately, and they are treated
with admirable tact and knowledge. The first essay on the Philosophy of Style if
worth the cost of the volume ; it would be a deed of charity to print it by Itself, and
lend it to the editor of every newspaper in the land." — New Englander.

■ Spencer is continually gaining ground with Americans; he makes a book for our
more serious moods. His remarks npon legislation, upon the nature of political Uibtl-
tutlons and of then- fundamental principles; his elucidation of those foundation truth*
which control the policy of government, are of peculiar value to the American sto-
denLr'--Boston Post.

uThis volume will receive the applause of every serious reader lor the profound
earnestness and thoroughness with which its views are elaborated, the infinite scientific
knowledge brought to bear on every question, and the acute and subtle thinking dhv
played in every chapter." — K. W. Christian Advocate.

"A more instructive, suggestive, and stimulating volume has not reached u Ui
Urn a." — Pi evidence Journal.

D. APPLET ON & CO:S PUBLICATION'S.

THE

Correlation and Conservation of Forces.

WITH AN

INTRODUCTION AND BRIEF BIOGRAPHICAL NOTICES
By EDWARD L. YOU MANS, M.D. 12mo, 490 pages.

CONTENTS.
L By W. R. Grove. The Correlation of Physical .Forces.
IL By Prof. Helmholtz. The Interaction of Natural Forces.

III. By J. R. Mayek. 1. Remarks on the Forces of Inorganic Nature.

2. On Celestial Dynamics.

3. On the Mechanical Equivalent of Heat.

IV. By Dr. Faraday. Some Thoughts on the Conservation of Forces.

V. By Prof. Liebio. The Connection and Equivalence of Forces.

VI. By Dr. Carpenter. The Correlation of the Physical and Vital Forces

This work is a very welcome addition to our scientific literature, and will be
particularly acceptable to those who wish to obtain a popular, but at the same time
precise and clear view of what Faraday justly calls the highest law in physical science,
the principle of the conservation of force. Sufficient attention has not been paid to the
publication of collected monographs or memoirs upon special subjects. Dr. Youmans'
work exhibits the value of such collections in a very striking manneu, and we earnestly
hope his excellent example may be followed in other branches of science." — American
Journal of Science.

"It was a happy thought which suggested the publication of this volume. The
question is often asked, and not so easily answered, What are the new doctrines of the
Correlation and Conservation of Forces? In this volume wo have the answer, and
v»Mth the reasons of Us chief expounders; those who are ignorant on that theme, can
thus question the original authorities." — New Englander.

"Wo here have the original expositions of tho new Philosophy of Forces, accompa-
nied by an excellent exposition of both the exposiU^ns and tho expositor*; tho whole
will be a rare treat to tho lovers of advancing scientific thought,"— Mtthoditd
Quarterly Review.

"This is, peihaps, tho most remarkablo book of tho age. Wo have hero tho l&teal
discoveries, and the highest results of thought Concerning the nature, laws, and con-
nections of tho forces of the universe. No higher or more sublime problem can » npr>g«
the Intellect of man than Is discussed by these doctors of science Intent alone on anlr
tag tt tho truth." — Detroit Free /'rent.

,T,hlB work presents a praiseworthy specimen of complete and faithful iiuthcnihl|%
and 1U publication ut thll time will form an epoch In th» MptHttOf of BMDJ thinking
mind*,"— lb tin*.

Works of Herbert Spencer putdished by D. Appldon & Co.

ILLUSTRATIONS OF UNIVERSAL PROGRESS,

A SERIES OF DISCUSSIONS.

1 Vol Larse 12mo. 470 Pages. Price $2.50.

CONTENTS :

American Notice of Spencer's New System of Philosophy.

L Progress : its Law and Cause.

II, Manners and Fashion,

m. The Genesis of Science.

IV. The Physiology of Laughter.

V. The Origin and Function of Music.
VL The Nebular Hypothesis.

VIL Bab on the Emotions and the Will.

VIIL Dlogical Geology.

IX. The Development Hypothesis.

X The Social Organism.

XL Use and Beauty.

XIL The Sources of Architectural Tjpes.

XI1T. The Dse of Anthropomorphism.

These Essays constitute a body of massive and original thought upon ■
large variety of important topics, and will be read with pleasure by all who
appreciate a bold and powerful treatment of fundamental themes. The
general thought which pervades this book is beyond doubt the most impor-
tant that the human mind has yet reached. — N. Y. Independent.

Those who have read the work on Education, will remember the ana-
lytic tendency of the author's mind — his clear perception and admirable ex-
position of hrst principles — his wide grasp of facts — his lucid and vigorous
•tyle, and the constant and controlling bearing of the discussion on practical
results. These traits characterize all Mr. Spencer's writings, and mark, in
an eminent degree, the present volume. — iV. Y. Tribune.

We regard the distinguishing feature of this work to be the peculiarly
Interesting character of its matter to the general reader. This is a great
literary as well as philosophic triumph. In the evolution of a system of
Philosophy which demands serious attention, and a keen exercise of the in-
tellect to fathom and appreciate, he has mingled much that is really popular
Mid entertaining. — Rochester Democrat

Works published ly D. Appleton db Go.

HEAT,

CONSIDERED AS A MODE OF MOTION,

Being a Course of Twelve Lectures delivered before the
Royal Institution of Great Britain.

BY JOfftf TYNDALL, P. E. 8.,

ntoKKssoE or natural potlosopiiy in the eoyal INSTITUTION— AUTHOE 3» ou
"GLACIEES of the alps," eto.

With One Hundred Illustrations. 8vo, 480 pages. Price, $2.

From the American Journal of Science. — With all the skill which has
made Faraday the master of experimental science in Great Britain, Professor Tyndall
enjoys the advantage of a superior general culture, and is thus enabled to set forth his
philosophy with all the graces of eloquence and the finish of superior diction. With a
simplicity, and absence of technicalities, which render his explanations lucid to un-
scientific minds, and at the same time a thoroughness and originality by which he in-
structs the most learned, he unfolds all the modern philosophy of heat. His work takes
rank at once as a classic upon the subject.

New York Times.— Professor Tyndall's course of lectures on heat is one of the
most beautiful illustrations of a mode of handling scientific subjects, which is com-
paratively new, and which promises the best results, both to science and to literature
generally ; we mean the treatment of subjects in a style at once profound and popu-
lar. The title of Professor Tyndall's work indicates the theory of heat held by him,
and indeed the only one now held by scientific men— it is a mode of motion.

Boston Journal.— He exhibits the curious and beautiful workings of nature in
a most delightful manner. Before the reader particles of water lock themselves or fly
asunder with a movement regulated like a dance. They form themselves iuto liquid
flowers with fine serrated petals, or into rosettes of frozen gauze; they bound upward
In boiling fountains, or creep slowly onward in stupendous glaciers. Flames buret into
music and sing, or cease to sing, as the experimenter pleases, and metals paint them-
selves upon a screen in dazzling hucB as the painter touches his canvas.

New York Tribune.— The most original and important contribution that has
yet been made to tho theory and literature of thcrmotics.

Scientihc American.— The work Is written In a charming style, and is the
most valuable contribution to scientific literature that bis been published in many
years. It is the most popular exposition of tho dynamical theory of heat thut has yet
sppeared. The old material theory of heat may bo said to be defunct.

Louisville Democrat.— This is one of tho most delightful scientific works we
bare ever met. The lectures are so full of life and spirit that wo can almost imagine
the lecturer before us, and see his brilliant experiment! in every stage of their progress.
The theory is so carefully and thoroughly explained that no one can fall to understand
tt» Such books as theso create a lovo for science.

Independent.— Professor Tyndall's expositions and experiments are remarkably
thoughtful, Ingenious, clear, and convliwing; portions of the beet have almo»t the
laterest of a romance, bo startling are tho dobcrii>tions and elucidation*.

" One of the most accomplished Writers of the Age."

HISTORY

or tii*

RISE AKD IOTTLTJENCE

or tub spirit or

RATIONALISM IN EUROPE

By W. E. II. LECKY, JVI. A..
2 Vols, small 8vo. Cloth, $<i.

[From the Edinburgh Reekie.]

" Wo opened these volumes, never baring heard the name of their author, and
entirely ignorant of bis pretensions to a place In English literature. Wo closed
them with the conviction that Mr. Leekjr Is one of the most accomplished writers

ami <>• f the tu<»»t ingenious thlnlii rs of the time, and that his \«h<V. <l< mtvc.i

the highest commendation we can bestow upon it Indeed, It has seldom beea*
our good fortune to take np an essay by an unknown, and we presume, s young
author, so remarkable for tbe purity and elegance of its style, so replete with
varied erudition, appropriately Introduced to enliven argument, or so distinguished
for broad and dispassionate views. • ••••• This book well deserves to be

universally read and carefully studied, for If the eye Is dazzled at first by the brtl«
llancy of tbe fervor, the mind is Interested and occupied by the subtlety nn<l pjpp
splculty of a thousand observations which escape notice on a first perusal. In a
word, we hope to see this work tako 1U place among the best literary production*
of tho age, and we donbt not that It will powerfully conduce to the ultimate Ul-
■ mjth of that cause to which It Is devoted."

D. APPLETOM A CO., Publishers,
ji'J & III Broad hu), ItW York.

3H365 20111
1871, v. 2

Darwin, Charles

The Hescent of *an

RALPH f. WOOLLEY l'WWAWv

Th« Ovrch ColUcre of Hawaii

DUE DATE

JAN 2 r iqqfl

J*N2 0 1988

JAN 3 0 1988