The Variation of Animals and Plants under Domestication
by
Charles Darwin

Part 6 out of 10



and other Malay hens, two or three years old, laid eggs very little larger
than a good sized Bantam's egg. Some were as white as a Spanish hen's egg,
and others varied from a light cream-colour to a deep rich buff, or even to
a brown." The shape also varies, the two ends being much more equally
rounded in Cochins than in Games or Polish. Spanish fowls lay smoother eggs
than Cochins, of which the eggs are generally granulated. The shell in this
latter breed, and more especially in Malays is apt to be thicker than in
Games or Spanish; but the Minorcas, a sub-breed of Spanish, are said to lay
harder eggs than true Spanish. (7/38. 'The Cottage Gardener' October 1855
page 13. On the thinness of the eggs of Game-fowls see Mowbray on 'Poultry'
7th edition page 13.) The colour differs considerably,--the Cochins laying
buff-coloured eggs; the Malays a paler variable buff; and Games a still
paler buff. It would appear that darker-coloured eggs characterise the
breeds which have lately come from the East, or are still closely allied to
those now living there. The colour of the yolk, according to Ferguson, as
well as of the shell, differs slightly in the sub-breeds of the Game. I am
also informed by Mr. Brent that dark partridge-coloured Cochin hens lay
darker coloured eggs than the other Cochin sub-breeds. The flavour and
richness of the egg certainly differ in different breeds. The
productiveness of the several breeds is very different. Spanish, Polish,
and Hamburgh hens have lost the incubating instinct.

CHICKENS.

As the young of almost all gallinaceous birds, even of the black curassow
and black grouse, whilst covered with down, are longitudinally striped on
the back,--of which character, when adult, neither sex retains a trace,--it
might have been expected that the chickens of all our domestic fowls would
have been similarly striped. (7/39. My information, which is very far from
perfect, on chickens in the down, is derived chiefly from Mr. Dixon's
'Ornamental and Domestic Poultry.' Mr. B.P. Brent has also communicated to
me many facts by letter, as has Mr. Tegetmeier. I will in each case mark my
authority by the name within brackets. For the chickens of white Silk fowls
see Tegetmeier 'Poultry Book' 1866 page 221.) This could, however, hardly
have been expected, when the adult plumage in both sexes has undergone so
great a change as to be wholly white or black. In white fowls of various
breeds the chickens are uniformly yellowish white, passing in the black-
boned Silk fowl into bright canary-yellow. This is also generally the case
with the chickens of white Cochins, but I hear from Mr. Zurhost that they
are sometimes of a buff or oak colour, and that all those of this latter
colour, which were watched, turned out males. The chickens of buff Cochins
are of a golden-yellow, easily distinguishable from the paler tint of the
white Cochins, and are often longitudinally streaked with dark shades: the
chickens of silver-cinnamon Cochins are almost always of a buff colour. The
chickens of the white Game and white Dorking breeds, when held in
particular lights, sometimes exhibit (on the authority of Mr. Brent) faint
traces of longitudinal stripes. Fowls which are entirely black, namely,
Spanish, black Game, black Polish, and black Bantams, display a new
character, for their chickens have their breasts and throats more or less
white, with sometimes a little white elsewhere. Spanish chickens also,
occasionally (Brent), have, where the down was white, their first true
feathers tipped for a time with white. The primordially striped character
is retained by the chickens of most of the Game sub-breeds (Brent, Dixon);
by Dorkings; by the partridge and grouse-coloured sub-breeds of Cochins
(Brent), but not, as we have seen, by the sub-breeds; by the pheasant-Malay
(Dixon), but apparently not (at which I am much surprised) by other Malays.
The following breeds and sub-breeds are barely, or not at all,
longitudinally striped: viz., gold and silver pencilled Hamburghs, which
can hardly be distinguished from each other (Brent) in the down, both
having a few dark spots on the head and rump, with occasionally a
longitudinal stripe (Dixon) on the back of the neck. I have seen only one
chicken of the silver-spangled Hamburgh, and this was obscurely striped
along the back. Gold-spangled Polish chickens (Tegetmeier) are of a warm
russet brown; and silver-spangled Polish chickens are grey, sometimes
(Dixon) with dashes of ochre on the head, wings, and breast. Cuckoo and
blue-dun fowls (Dixon) are grey in the down. The chickens of Sebright
Bantams (Dixon) are uniformly dark brown, whilst those of the brown-
breasted red Game Bantam are black, with some white on the throat and
breast. From these facts we see that young chickens of the different
breeds, and even of the same main breed, differ much in their downy
plumage; and, although longitudinal stripes characterise the young of all
wild gallinaceous birds, they disappear in several domestic breeds. Perhaps
it may be accepted as a general rule that the more the adult plumage
differs from that of the adult G. bankiva, the more completely the chickens
have lost their stripes.]

With respect to the period of life at which the characters proper to each
breed first appear, it is obvious that such structures as additional toes
must be formed long before birth. In Polish fowls, the extraordinary
protuberance of the anterior part of the skull is well developed before the
chickens come out of the egg (7/40. As I hear from Mr. Tegetmeier; see also
'Proc. Zoolog. Soc.' 1856 page 366. On the late development of the crest
see 'Poultry Chronicle' volume 2 page 132.) but the crest, which is
supported on the protuberance, is at first feebly developed, nor does it
attain its full size until the second year. The Spanish cock is pre-eminent
for his magnificent comb, and this is developed at an unusually early age;
so that the young males can be distinguished from the females when only a
few weeks old, and therefore earlier than in other breeds; they likewise
crow very early, namely, when about six weeks old. In the Dutch sub-breed
of the Spanish fowl the white ear-lappets are developed earlier than in the
common Spanish breed. (7/41. On these points see 'Poultry Chronicle' volume
3 page 166; and Tegetmeier 'Poultry Book' 1866 pages 105 and 121.) Cochins
are characterised by a small tail, and in the young cocks the tail is
developed at an unusually late period. (7/42. Dixon 'Ornamental and
Domestic Poultry' page 273.) Game fowls are notorious for their pugnacity;
and the young cocks crow, clap their little wings, and fight obstinately
with each other, even whilst under their mother's care. (7/43. Ferguson on
'Rare and Prize Poultry' page 261.) "I have often had," says one author
(7/44. Mowbray on 'Poultry' 7th edition 1834 page 13.), "whole broods,
scarcely feathered, stone-blind from fighting; the rival couples moping in
corners, and renewing their battles on obtaining the first ray of light."
The weapons and pugnacity of all male gallinaceous birds evidently serve
the purpose of gaining possession of the females; so that the tendency in
our Game chickens to fight at an extremely early age is not only useless,
but injurious, as they suffer much from their wounds. The training for
battle during an early age may be natural to the wild Gallus bankiva; but
as man during many generations has gone on selecting the most obstinately
pugnacious cocks, it is more probable that their pugnacity has been
unnaturally increased, and unnaturally transferred to the young male
chickens. In the same manner, it is probable that the extraordinary
development of the comb in the Spanish cock has been unintentionally
transferred to the young cocks; for fanciers would not care whether their
young birds had large combs, but would select for breeding the adults which
had the finest combs, whether or not developed at an early period. The last
point which need here be noticed is that, though the chickens of Spanish
and Malay fowls are well covered with down, the true feathers are acquired
at an unusually late age; so that for a time the young birds are partially
naked, and are liable to suffer from cold.

SECONDARY SEXUAL CHARACTERS.

The two sexes in the parent-form, the Gallus bankiva, differ much in
colour. In our domestic breeds the difference is never greater, but is
often less, and varies much in degree even in the sub-breeds of the same
main breed. Thus in certain Game fowls the difference is as great as in the
parent-form, whilst in the black and white sub-breeds there is no
difference in plumage. Mr. Brent informs me that he has seen two strains of
black-breasted red Games, of which the cocks could not be distinguished,
whilst the hens in one were partridge-brown and in the other fawn-brown. A
similar case has been observed in the strains of the brown-breasted red
Game. The hen of the "duck-winged Game" is "extremely beautiful," and
differs much from the hens of all the other Game sub-breeds; but generally,
as with the blue and grey Game and with some sub-varieties of the pile-
game, a moderately close relation may be observed between the males and
females in the variation of their plumage. (7/45. See the full description
of the varieties of the Game-breed in Tegetmeier 'Poultry Book' 1866 page
131. For Cuckoo Dorkings page 97.) A similar relation is also evident when
we compare the several varieties of Cochins. In the two sexes of gold and
silver-spangled and of buff Polish fowls, there is much general similarity
in the colouring and marks of the whole plumage, excepting of course in the
hackles, crest, and beard. In spangled Hamburghs, there is likewise a
considerable degree of similarity between the two sexes. In pencilled
Hamburghs, on the other hand, there is much dissimilarity; the pencilling
which is characteristic of the hens being almost absent in the males of
both the golden and silver varieties. But, as we have already seen, it
cannot be given as a general rule that male fowls never have pencilled
feathers, for Cuckoo Dorkings are "remarkable from having nearly similar
markings in both sexes."

It is a singular fact that the males in certain sub-breeds have lost some
of their secondary masculine characters, and from their close resemblance
in plumage to the females, are often called hennies. There is much
diversity of opinion whether these males are in any degree sterile; that
they sometimes are partially sterile seems clear (7/46. Mr. Hewitt in
Tegetmeier 'Poultry Book' 1866 pages 246 and 156. For hen-tailed game-cocks
see page 131.), but this may have been caused by too close interbreeding.
That they are not quite sterile, and that the whole case is widely
different from that of old females assuming masculine characters, is
evident from several of these hen-like sub-breeds having been long
propagated. The males and females of gold and silver-laced Sebright Bantams
can be barely distinguished from each other, except by their combs,
wattles, and spurs, for they are coloured alike, and the males have not
hackles, nor the flowing sickle-like tail-feathers. A hen-tailed sub-breed
of Hamburghs was recently much esteemed. There is also a breed of Game-
fowls, in which the males and females resemble each other so closely that
the cocks have often mistaken their hen-feathered opponents in the cock-pit
for real hens, and by the mistake have lost their lives. (7/47. 'The Field'
April 20, 1861. The writer says he has seen half-a-dozen cocks thus
sacrificed.) The cocks, though dressed in the feathers of the hen, "are
high-spirited birds, and their courage has been often proved:" an engraving
even has been published of one celebrated hen-tailed victor. Mr. Tegetmeier
(7/48. 'Proceedings of Zoolog. Soc.' March 1861 page 102. The engraving of
the hen-tailed cock just alluded to was exhibited before the Society.) has
recorded the remarkable case of a brown-breasted red Game cock which, after
assuming its perfect masculine plumage, became hen-feathered in the autumn
of the following year; but he did not lose voice, spurs, strength, nor
productiveness. This bird has now retained the same character during five
seasons, and has begot both hen-feathered and male-feathered offspring. Mr.
Grantley F. Berkeley relates the still more singular case of a celebrated
strain of "polecat Game fowls," which produced in nearly every brood a
single hen-cock. "The great peculiarity in one of these birds was that he,
as the seasons succeeded each other, was not always a hen-cock, and not
always of the colour called the polecat, which is black. From the polecat
and hen-cock feather in one season he moulted to a full male-plumaged
black-breasted red, and in the following year he returned to the former
feather." (7/49. 'The Field' April 20, 1861.)

I have remarked in my 'Origin of Species' that secondary sexual characters
are apt to differ much in the species of the same genus, and to be
unusually variable in the individuals of the same species. So it is with
the breeds of the fowl, as we have already seen, as far as the colour of
plumage is concerned, and so it is with the other secondary sexual
characters. Firstly, the comb differs much in the various breeds (7/50. I
am much indebted to Mr. Brent for an account, with sketches, of all the
variations of the comb known to him, and likewise with respect to the tail
as presently to be given), and its form is eminently characteristic of each
kind, with the exception of the Dorkings, in which the form has not been as
yet determined on by fanciers, and fixed by selection. A single, deeply-
serrated comb is the typical and most common form. It differs much in size,
being immensely developed in Spanish fowls; and in a local breed called
Red-caps, it is sometimes "upwards of three inches in breadth at the front,
and more than four inches in length, measured to the end of the peak
behind." (7/51. The 'Poultry Book' by Tegetmeier 1866 page 234.) In some
breeds the comb is double, and when the two ends are cemented together it
forms a "cup-comb;" in the "rose-comb" it is depressed, covered with small
projections, and produced backwards; in the horned and creve-coeur fowl it
is produced into two horns; it is triple in the pea-combed Brahmas, short
and truncated in the Malays, and absent in the Guelderlands. In the
tasselled Game a few long feathers rise from the back of the comb: in many
breeds a crest of feathers replaces the comb. The crest, when little
developed, arises from a fleshy mass, but, when much developed, from a
hemispherical protuberance of the skull. In the best Polish fowls it is so
largely developed, that I have seen birds which could hardly pick up their
food; and a German writer asserts (7/52. 'Die Huhner- und Pfauenzucht' 1827
s. 11.) that they are in consequence liable to be struck by hawks.
Monstrous structures of this kind would thus be suppressed in a state of
nature. The wattles, also, vary much in size, being small in Malays and
some other breeds; in certain Polish sub-breeds they are replaced by a
great tuft of feathers called a beard.

The hackles do not differ much in the various breeds, but are short and
stiff in Malays, and absent in Hennies. As in some orders male birds
display extraordinarily-shaped feathers, such as naked shafts with discs at
the end, etc., the following case may be worth giving. In the wild Gallus
bankiva and in our domestic fowls, the barbs which arise from each side of
the extremities of the hackles are naked or not clothed with barbules, so
that they resemble bristles; but Mr. Brent sent me some scapular hackles
from a young Birchen Duckwing Game cock, in which the naked barbs became
densely re-clothed with barbules towards their tips; so that these tips,
which were dark coloured with a metallic lustre, were separated from the
lower parts by a symmetrically-shaped transparent zone formed of the naked
portions of the barbs. Hence the coloured tips appeared like little
separate metallic discs.

The sickle-feathers in the tail, of which there are three pair, and which
are eminently characteristic of the male sex, differ much in the various
breeds. They are scimitar-shaped in some Hamburghs, instead of being long
and flowing as in the typical breeds. They are extremely short in Cochins,
and are not at all developed in Hennies. They are carried, together with
the whole tail, erect in Dorkings and Gaines; but droop much in Malays and
in some Cochins. Sultans are characterised by an additional number of
lateral sickle-feathers. The spurs vary much, being placed higher or lower
on the shank; being extremely long and sharp in Games, and blunt and short
in Cochins. These latter birds seem aware that their spurs are not
efficient weapons; for though they occasionally use them, they more
frequently fight, as I am informed by Mr. Tegetmeier, by seizing and
shaking each other with their beaks. In some Indian Game cocks, received by
Mr. Brent from Germany, there are, as he informs me, three, four, or even
five spurs on each leg. Some Dorkings also have two spurs on each leg
(7/53. 'Poultry Chronicle' volume 1 page 595. Mr. Brent has informed me of
the same fact. With respect to the position of the spurs in Dorkings see
'Cottage Gardener' September 18, 1860 page 380.); and in birds of this
breed the spur is often placed almost on the outside of the leg. Double
spurs are mentioned in an ancient Chinese Encyclopaedia. Their occurrence
may be considered as a case of analogous variation, for some wild
gallinaceous birds, for instance, the Polyplectron, have double spurs.

Judging from the differences which generally distinguish the sexes in the
Gallinaceae, certain characters in our domestic fowls appear to have been
transferred from the one sex to the other. In all the species (except in
Turnix), when there is any conspicuous difference in plumage between the
male and female, the male is always the most beautiful; but in golden-
spangled Hamburghs the hen is equally beautiful with the cock, and
incomparably more beautiful than the hen in any natural species of Gallus;
so that here a masculine character has been transferred to the female. On
the other hand, in Cuckoo Dorkings and in other cuckoo breeds the
pencilling, which in Gallus is a female attribute, has been transferred to
the male: nor, on the principle of analogous variation, is this
transference surprising, as the males in many gallinaceous genera are
barred or pencilled. With most of these birds head ornaments of all kinds
are more fully developed in the male than in the female; but in Polish
fowls the crest or top-knot, which in the male replaces the comb, is
equally developed in both sexes. In the males of certain other sub-breeds,
which from the hen having a small crest, are called lark-crested, "a single
upright comb sometimes almost entirely takes the place of the crest."
(7/54. Dixon 'Ornamental and Domestic Poultry' page 320.) From this latter
case, and more especially from some facts presently to be given with
respect to the protuberance of the skull in Polish fowls, the crest in this
breed must be viewed as a feminine character which has been transferred to
the male. In the Spanish breed the male, as we know, has an immense comb,
and this has been partially transferred to the female, for her comb is
unusually large, though not upright. In Game fowls the bold and savage
disposition of the male has likewise been largely transferred to the female
(7/55. Mr. Tegetmeier informs me that Game hens have been found so
combative, that it is now generally the practice to exhibit each hen in a
separate pen.); and she sometimes even possesses the eminently masculine
character of spurs. Many cases are on record of fertile hens being
furnished with spurs; and in Germany, according to Bechstein (7/56.
'Naturgeschichte Deutschlands' b. 3 1793 s. 339, 407.), the spurs in the
Silk hen are sometimes very long. He mentions also another breed similarly
characterised, in which the hens are excellent layers, but are apt to
disturb and break their eggs owing to their spurs.

Mr. Layard (7/57. On the Ornithology of Ceylon in 'Annals and Mag. of Nat.
History.' 2nd series volume 14 1854 page 63.) has given an account of a
breed of fowls in Ceylon with black skin, bones, and wattle, but with
ordinary feathers, and which cannot "be more aptly described than by
comparing them to a white fowl drawn down a sooty chimney; it is, however,"
adds Mr. Layard, "a remarkable fact that a male bird of the pure sooty
variety is almost as rare as a tortoise-shell tom-cat." Mr. Blyth found the
same rule to hold good with this breed near Calcutta. The males and
females, on the other hand, of the black-boned European breed, with silky
feathers, do not differ from each other; so that in the one breed, black
skin and bones and the same kind of plumage are common to both sexes,
whilst in the other breed, these characters are confined to the female sex.

At the present day all the breeds of Polish fowls have the great bony
protuberance on their skulls, which includes part of the brain and supports
the crest, equally developed in both sexes. But formerly in Germany the
skull of the hen alone was protuberant: Blumenbach (7/58. 'Handbuch der
vergleich. Anatomie' 1805 page 85 note. Mr. Tegetmeier, who gives in 'Proc.
Zoolog. Soc.' November 25, 1856 a very interesting account of the skulls of
Polish fowls, not knowing of Bechstein's account, has disputed the accuracy
of Blumenbach's statement. For Bechstein see 'Naturgeschichte Deutschlands'
b. 3 1793 s. 399 note. I may add that at the first exhibition of Poultry at
the Zoological Gardens in May 1845 I saw some fowls, called Friezland
fowls, of which the hens were crested, and the cocks furnished with a
comb.), who particularly attended to abnormal peculiarities in domestic
animals, states, in 1805, that this was the case; and Bechstein had
previously, in 1793 observed the same fact. This latter author has
carefully described the effects on the skull of a crest not only in the
case of fowls, but of ducks, geese, and canaries. He states that with
fowls, when the crest is not much developed, it is supported on a fatty
mass; but when much developed, it is always supported on a bony
protuberance of variable size. He well describes the peculiarities of this
protuberance; he attended also to the effects of the modified shape of the
brain on the intellect of these birds, and disputes Pallas' statement that
they are stupid. He then expressly remarks that he never observed this
protuberance in male fowls. Hence there can be no doubt that this
extraordinary character in the skulls of Polish fowls was formerly in
Germany confined to the female sex, but has now been transferred to the
males, and has thus become common to both sexes.

[EXTERNAL DIFFERENCES, NOT CONNECTED WITH THE SEXES, BETWEEN THE BREEDS AND
BETWEEN INDIVIDUAL BIRDS.

The size of the body differs greatly. Mr. Tegetmeier has known a Brahma to
weigh 17 pounds; a fine Malay cock 10 pounds; whilst a first-rate Sebright
Bantam weighs hardly more than 1 pound. During the last 20 years the size
of some of our breeds has been largely increased by methodical selection,
whilst that of other breeds has been much diminished. We have already seen
how greatly colour varies even within the same breed; we know that the wild
G. bankiva varies slightly in colour; we know that colour is variable in
all our domestic animals; nevertheless some eminent fanciers have so little
faith in variability, that they have actually argued that the chief Game
sub-breeds, which differ from each other in nothing but colour, are
descended from distinct wild species! Crossing often causes strange
modification of colour. Mr. Tegetmeier informs me that when buff and white
Cochins are crossed, some of the chickens are almost invariably black.
According to Mr. Brent, black and white Cochins occasionally produce
chickens of a slaty-blue tint; and this same tint results, as Mr.
Tegetmeier tells me, from crossing white Cochins with black Spanish fowls,
or white Dorkings with black Minorcas. (7/59. 'Cottage Gardener' January 3,
1860 page 218.) A good observer (7/60. Mr. Williams in a paper read before
the Dublin Nat. Hist. Soc. quoted in 'Cottage Gardener' 1856 page 161.)
states that a first-rate silver-spangled Hamburgh hen gradually lost the
most characteristic qualities of the breed, for the black lacing to her
feathers disappeared, and her legs changed from leaden-blue to white: but
what makes the case remarkable is, that this tendency ran in the blood for
her sister changed in a similar but less strongly marked manner; and
chickens produced from this latter hen were at first almost pure white,
"but on moulting acquired black colours and some spangled feathers with
almost obliterated markings;" so that a new variety arose in this singular
manner. The skin in the different breeds differs much in colour, being
white in common kinds, yellow in Malays and Cochins, and black in Silk
fowls; thus mocking, as M. Godron (7/61. 'De l'Espece' 1859 page 442. For
the occurrence of black-boned fowls in South America, see Roulin in 'Mem.
de l'Acad. des Sciences' tome 6 page 351; and Azara, 'Quadrupedes du
Paraguay' tome 2 page 324. A frizzled fowl sent to me from Madras had black
bones.) remarks the three principal types of skin in mankind. The same
author adds that, as different kinds of fowls living in distant and
isolated parts of the world have black skin and bones, this colour must
have appeared at various times and places.

The shape and carriage of the body, and the shape of the head differ much.
The beak varies slightly in length and curvature, but incomparably less
than with pigeons. In most crested fowls the nostrils offer a remarkable
peculiarity in being raised with a crescentic outline. The primary wing-
feathers are short in Cochins; in a male, which must have been more than
twice as heavy as G. bankiva, these feathers were in both birds of the same
length. I have counted, with Mr. Tegetmeier's aid, the primary wing-
feathers in thirteen cocks and hens of various breeds; in four of them,
namely in two Hamburghs, a Cochin, and Game bantam, there were 10, instead
of the normal number 9; but in counting these feathers I have followed the
practice of fanciers, and have NOT included the first minute primary
feather, barely three-quarters of an inch in length. These feathers differ
considerably in relative length, the fourth, or the fifth, or the sixth,
being the longest; with the third either equal to, or considerably shorter
than the fifth. In wild gallinaceous species the relative length and number
of the main wing and tail-feathers are extremely constant.

The tail differs much in erectness and size, being small in Malays and very
small in Cochins. In thirteen fowls of various breeds which I have
examined, five had the normal number of 14 feathers, including in this
number the two middle sickle-feathers; six others (viz., a Caffre cock,
Gold-spangled Polish cock, Cochin hen, Sultan hen, Game hen and Malay hen
had 16; and two (an old Cochin cock and Malay hen) had 17 feathers. The
rumpless fowl has no tail and in one which I possessed there was no oil-
gland; but this bird though the os coccygis was extremely imperfect, had a
vestige of a tail with two rather long feathers in the position of the
outer caudals. This bird came from a family where, as I was told, the breed
had kept true for twenty years; but rumpless fowls often produce chickens
with tails. (7/62. Mr. Hewitt in Tegetmeier 'Poultry Book' 1866 page 231.)
An eminent physiologist (7/63. Dr. Broca in Brown-Sequard 'Journal de
Phys.' tome 2 page 361.) has recently spoken of this breed as a distinct
species; had he examined the deformed state of the os coccyx he would never
have come to this conclusion; he was probably misled by the statement,
which may be found in some works, that tailless fowls are wild in Ceylon;
but this statement, as I have been assured by Mr. Layard and Dr. Kellaert
who have so closely studied the birds of Ceylon, is utterly false.

The tarsi vary considerably in length, being relatively to the femur
considerably longer in the Spanish and Frizzled, and shorter in the Silk
and Bantam breeds, than in the wild G. bankiva; but in the latter, as we
have seen, the tarsi vary in length. The tarsi are often feathered. The
feet in many breeds are furnished with additional toes. Golden-spangled
Polish fowls are said (7/64. Dixon 'Ornamental Poultry' page 325.) to have
the skin between their toes much developed: Mr. Tegetmeier observed this in
one bird, but it was not so in one which I examined. Prof. Hoffmann has
sent me a sketch of the feet of a fowl of the common breed at Giessen, with
a web extending between the three toes, for about a third of their length.
In Cochins the middle toe is said (7/65. 'Poultry Chronicle' volume 1 page
485. Tegetmeier 'Poultry Book' 1866 page 41. On Cochins grazing ibid page
46.) to be nearly double the length of the lateral toes, and therefore much
longer than in G. bankiva or in other fowls; but this was not the case in
two which I examined. The nail of the middle toe in this same breed is
surprisingly broad and flat, but in a variable degree in two birds which I
examined; of this structure in the nail there is only a trace in G.
bankiva.

The voice differs slightly, as I am informed by Mr. Dixon, in almost every
breed. The Malays (7/66. Ferguson on 'Prize Poultry' page 87.) have a loud,
deep, somewhat prolonged crow, but with considerable individual difference.
Colonel Sykes remarks that the domestic Kulm cock in India has not the
shrill clear pipe of the English bird, and "his scale of notes appears more
limited." Dr. Hooker was struck with the "prolonged howling screech" of the
cocks in Sikhim. (7/67. Col. Sykes in 'Proc. Zoolog. Soc.' 1832 page 151.
Dr. Hooker's 'Himalayan Journals' volume 1 page 314.) The crow of the
Cochin is notoriously and ludicrously different from that of the common
cock. The disposition of the different breeds is widely different, varying
from the savage and defiant temper of the Game-cock to the extremely
peaceable temper of the Cochins. The latter, it has been asserted, "graze
to a much greater extent than any other varieties." The Spanish fowls
suffer more from frost than other breeds.]

Before we pass on to the skeleton, the degree of distinctness of the
several breeds from G. bankiva ought to be noticed. Some writers speak of
the Spanish as one of the most distinct breeds, and so it is in general
aspect; but its characteristic differences are not important. The Malay
appears to me more distinct, from its tall stature, small drooping tail
with more than fourteen tail-feathers, and from its small comb and wattles;
nevertheless, one Malay sub-breed is coloured almost exactly like G.
bankiva. Some authors consider the Polish fowl as very distinct; but this
is a semi-monstrous breed, as shown by the protuberant and irregularly
perforated skull. The Cochin, from its deeply furrowed frontal bones,
peculiarly shaped occipital foramen, short wing-feathers, short tail
containing more than fourteen feathers, broad nail to the middle toe,
fluffy plumage, rough and dark-coloured eggs, and especially from its
peculiar voice, is probably the most distinct of all the breeds. If any one
of our breeds has descended from some unknown species, distinct from G.
bankiva, it is probably the Cochin; but the balance of evidence does not
favour this view. All the characteristic differences of the Cochin breed
are more or less variable, and may be detected in a greater or lesser
degree in other breeds. One sub-breed is coloured closely like G. bankiva.
The feathered legs, often furnished with an additional toe, the wings
incapable of flight, the extremely quiet disposition, indicate a long
course of domestication; and these fowls come from China, where we know
that plants and animals have been tended from a remote period with
extraordinary care, and where consequently we might expect to find
profoundly modified domestic races.

OSTEOLOGICAL DIFFERENCES.

I have examined twenty-seven skeletons and fifty-three skulls of various
breeds, including three of G. bankiva: nearly half of these skulls I owe to
the kindness of Mr. Tegetmeier, and three of the skeletons to Mr. Eyton.

SKULL.

(FIGURE 33. OCCIPITAL FORAMEN, of natural size. A. Wild Gallus bankiva. B.
Cochin Cock.

FIGURE 34. SKULLS of natural size, viewed from above, a little obliquely.
A. Wild Gallus bankiva. B. White-crested Polish Cock.

FIGURE 35. LONGITUDINAL SECTIONS OF SKULL, of natural size, viewed
laterally; A. Polish Cock. B. Cochin Cock, selected for comparison with the
above from being of nearly the same size.

FIGURE 36. SKULL OF HORNED FOWL, of natural size, viewed from above, a
little obliquely. (In the possession of Tegetmeier.))

[The SKULL differs greatly in size in different breeds, being nearly twice
as long in the largest Cochins, but not nearly twice as broad, as in
Bantams. The bones at the base, from the occipital foramen to the anterior
end (including the quadrates and pterygoids), are absolutely identical in
SHAPE in all the skulls. So is the lower jaw. In the forehead slight
differences are often perceptible between the males and females, evidently
caused by the presence of the comb. In every case I take the skull of G.
bankiva as the standard of comparison. In four Games, in one Malay hen, in
an African cock, in a Frizzled cock from Madras, in two black-boned Silk
hens, no differences worth notice occur. In three SPANISH cocks, the form
of the forehead between the orbits differs considerably; in one it is
considerably depressed, whilst in the two others it is rather prominent,
with a deep medial furrow; the skull of the hen is smooth. In three skulls
of SEBRIGHT BANTAMS the crown is more globular, and slopes more abruptly to
the occiput, than in G. bankiva. In a Bantam or Jumper from Burmah these
same characters are more strongly pronounced, and the supra-occiput is more
pointed. In a black Bantam the skull is not so globular, and the occipital
foramen is very large, and has nearly the same sub-triangular outline
presently to be described in Cochins; and in this skull the two ascending
branches of the premaxillary are overlapped in a singular manner by the
processes of the nasal bone, but, as I have seen only one specimen, some of
these differences may be individual. Of Cochins and Brahmas (the latter a
crossed race approaching closely to Cochins) I have examined seven skulls;
at the point where the ascending branches of the premaxillary rest on the
frontal bone the surface is much depressed, and from this depression a deep
medial furrow extends backwards to a variable distance; the edges of this
fissure are rather prominent, as is the top of the skull behind and over
the orbits. These characters are less developed in the hens. The
pterygoids, and the processes of the lower jaw, are broader, relatively to
the size of the head, than in G. bankiva; and this is likewise the case
with Dorkings when of large size. The fork of the hyoid bone in Cochins is
twice as wide as in G. bankiva, whereas the length of the other hyoid bones
is only as three to two. But the most remarkable character is the shape of
the occipital foramen: in G. bankiva (A) the breadth in a horizontal line
exceeds the height in a vertical line, and the outline is nearly circular;
whereas in Cochins (B) the outline is sub-triangular, and the vertical line
exceeds the horizontal line in length. This same form likewise occurs in
the black Bantam above referred to, and an approach to it may be seen in
some Dorkings, and in a slight degree in certain other breeds.

Of Dorkings I have examined three skulls, one belonging to the white-sub-
breed; the one character deserving notice is the breadth of the frontal
bones, which are moderately furrowed in the middle; thus in a skull which
was less than once and a half the length of that of G. bankiva, the breadth
between the orbits was exactly double. Of Hamburghs I have examined four
skulls (male and female) of the pencilled sub-breed, and one (male) of the
spangled sub-breed; the nasal bones stand remarkably wide apart, but in a
variable degree; consequently narrow membrane-covered spaces are left
between the tips of the two ascending branches of the pre-maxillary bones,
which are rather short, and between these branches and the nasal bones. The
surface of the frontal bone, on which the branches of the premaxillary
rest, is very little depressed. These peculiarities no doubt stand in close
relation with the broad, flattened rose-comb characteristic of the Hamburgh
breed.

I have examined fourteen skulls of POLISH AND OTHER CRESTED BREEDS. Their
differences are extraordinary. First for nine skulls of different sub-
breeds of English Polish fowls. The hemispherical protuberance of the
frontal bones (7/68. See Mr. Tegetmeier's account with woodcuts of the
skull of Polish fowls in 'Proc. Zoolog. Soc.' November 25, 1856. For other
references see Isid. Geoffroy Saint-Hilaire 'Hist. Gen. des Anomalies' tome
1 page 287. M. C. Dareste suspects ('Recherches sur les Conditions de la
Vie' etc. Lille 1863 page 36) that the protuberance is not formed by the
frontal bones, but by the ossification of the dura mater.) may be seen in
figure 34, in which (B) the skull of a white-crested Polish fowl is shown
obliquely from above, with the skull (A) of (G. bankiva in the same
position. In figure 35 longitudinal sections are given of the skull of a
Polish fowl, and, for comparison, of a Cochin of the same size. The
protuberance in all Polish fowls occupies the same position but differs
much in size. In one of my nine specimens it was extremely slight. The
degree to which the protuberance is ossified varies greatly, larger or
smaller portions of bone being replaced by membrane. In one specimen there
was only a single open pore; generally, there are many variously shaped
open spaces, the bone forming an irregular reticulation. A medial,
longitudinal, arched ribbon of bone is generally retained, but in one
specimen there was no bone whatever over the whole protuberance, and the
skull, when cleaned and viewed from above, presented the appearance of an
open basin. The change in the whole internal form of the skull is
surprisingly great. The brain is modified in a corresponding manner, as is
shown in the two longitudinal sections, which deserve attentive
consideration. The upper and anterior cavity of the three into which the
skull may be divided, is the one which is so greatly modified; it is
evidently much larger than in the Cochin skull of the same size, and
extends much further beyond the interorbital septum, but laterally is less
deep. This cavity, as I hear from Mr. Tegetmeier, is entirely filled with
brain. In the skull of the Cochin and of all ordinary fowls a strong
internal ridge of bone separates the anterior from the central cavity; but
this ridge is quite absent in the Polish skull here figured. The shape of
the central cavity is circular in the Polish, and lengthened in the Cochin
skull. The shape of the posterior cavity, together with the position, size,
and number of the pores for the nerves, differ much in these two skulls. A
pit deeply penetrating the occipital bone of the Cochin is entirely absent
in this Polish skull, whilst in another specimen it was well developed. In
this second specimen the whole internal surface of the posterior cavity
likewise differs to a certain extent in shape. I made sections of two other
skulls,--namely, of a Polish fowl with the protuberance singularly little
developed, and of a Sultan in which it was a little more developed; and
when these two skulls were placed between the two above figured (figure
35), a perfect gradation in the configuration of each part of the internal
surface could be traced. In the Polish skull, with a small protuberance,
the ridge between the anterior and middle cavities was present, but low;
and in the Sultan this ridge was replaced by a narrow furrow standing on a
broad raised eminence.

It may naturally be asked whether these remarkable modifications in the
form of the brain affect the intellect of Polish fowls; some writers have
stated that they are extremely stupid, but Bechstein and Mr. Tegetmeier
have shown that this is by no means generally the case. Nevertheless
Bechstein (7/69. 'Naturgeschichte Deutschlands' b. 3 1793 s. 400.) states
that he had a Polish hen which "was crazy, and anxiously wandered about all
day long." A hen in my possession was solitary in her habits, and was often
so absorbed in reverie that she could be touched; she was also deficient in
the most singular manner in the faculty of finding her way, so that, if she
strayed a hundred yards from her feeding-place, she was completely lost,
and would then obstinately try to proceed in a wrong direction. I have
received other and similar accounts of Polish fowls appearing stupid or
half-idiotic. (7/70. The 'Field' May 11, 1861. I have received
communications to a similar effect from Messrs. Brent and Tegetmeier.)

To return to the skull of Polish fowls. The posterior part, viewed
externally, differs little from that of G. bankiva. In most fowls the
posterior-lateral process of the frontal bone and the process of the
squamosal bone run together and are ossified near their extremities: this
union of the two bones, however, is not constant in any breed; and in
eleven out of fourteen skulls of crested breeds, these processes were quite
distinct. These processes, when not united, instead of being inclined
anteriorly, as in all common breeds, descend at right angles to the lower
jaw; and in this case the longer axis of the bony cavity of the ear is
likewise more perpendicular, than in other breeds. When the squamosal
process is free instead of expanding at the tip, it is reduced to an
extremely fine and pointed style, of variable length. The pterygoid and
quadrate bones present no differences. The palatine bones are a little more
curved upwards at their posterior ends. The frontal bones, anteriorly to
the protuberance, are, as in Dorkings, very broad, but in a variable
degree. The nasal bones either stand far apart, as in Hamburghs, or almost
touch each other, and in one instance were ossified together. Each nasal
bone properly sends out in front two long processes of equal lengths,
forming a fork; but in all the Polish skulls, except one, the inner process
was considerably, but in a variable degree, shortened and somewhat
upturned. In all the skulls, except one, the two ascending branches of the
premaxillary, instead of running up between the processes of the nasal
bones and resting on the ethmoid bone, are much shortened and terminate in
a blunt, somewhat upturned point. In those skulls in which the nasal bones
approach quite close to each other or are ossified together, it would be
impossible for the ascending branches of the premaxillary to reach the
ethmoid and frontal bones; hence we see that even the relative connection
of the bones has been changed. Apparently in consequence of the branches of
the premaxillary and of the inner processes of the nasal bones being
somewhat upturned, the external orifices of the nostrils are upraised and
assume a crescentic outline.

I must still say a few words on some of the foreign Crested breeds. The
skull of a crested, rumpless, white Turkish fowl was very slightly
protuberant, and but little perforated; the ascending branches of the
premaxillary were well developed. In another Turkish breed, called
Ghoondooks, the skull was considerably protuberant and perforated; the
ascending branches of the premaxillary were so much aborted that they
projected only 1/15th of an inch; and the inner processes of the nasal bone
were so completely aborted, that the surface where they should have
projected was quite smooth. Here then we see these two bones modified to an
extreme degree. Of Sultans (another Turkish breed) I examined two skulls;
in that of the female the protuberance was much larger than in the male. In
both skulls the ascending branches of the premaxillary were very short, and
in both the nasal portion of the inner processes of the nasal bones were
ossified together. These Sultan skulls differed from those of English
Polish fowls in the frontal bones, anteriorly to the protuberance, not
being broad.

The last skull which I need describe is a unique one, lent to me by Mr.
Tegetmeier: it resembles a Polish skull in most of its characters, but has
not the great frontal protuberance; it has, however, two rounded knobs of a
different nature, which stand more in front, above the lachrymal bones.
These curious knobs, into which the brain does not enter, are separated
from each other by a deep medial furrow; and this is perforated by a few
minute pores. The nasal bones stand rather wide apart, with their inner
processes, and the ascending branches of the premaxillary, upturned and
shortened. The two knobs no doubt supported the two great horn-like
projections of the comb.

From the foregoing facts we see in how astonishing a manner some of the
bones of the skull vary in Crested fowls. The protuberance may certainly be
called in one sense a monstrosity, as being wholly unlike anything observed
in nature: but as in ordinary cases it is not injurious to the bird, and as
it is strictly inherited, it can hardly in another sense be called a
monstrosity. A series may be formed commencing with the black-boned Silk
fowl, which has a very small crest with the skull beneath penetrated only
by a few minute orifices, but with no other change in its structure; and
from this first stage we may proceed to fowls with a moderately large
crest, which rests, according to Bechstein, on a fleshy mass, but without
any protuberance in the skull. I may add that I have seen a similar fleshy
or fibrous mass beneath the tuft of feathers on the head of the Tufted
duck; and in this case there was no actual protuberance in the skull, but
it had become a little more globular. Lastly, when we come to fowls with a
largely developed crest, the skull becomes largely protuberant and is
perforated by a multitude of irregular open spaces. The close relation
between the crest and the size of the bony protuberance is shown in another
way; for Mr. Tegetmeier informs me that if chickens lately hatched be
selected with a large bony protuberance, when adult they will have a large
crest. There can be no doubt that in former times the breeder of Polish
fowls attended solely to the crest, and not to the skull; nevertheless, by
increasing the crest, in which he has been wonderfully successful, he has
unintentionally made the skull protuberant to an astonishing degree; and
through correlation of growth, he has at the same time affected the form
and relative connexion of the premaxillary and nasal bones, the shape of
the orifice of the nose, the breadth of the frontal bones, the shape of the
post-lateral processes of the frontal and squamosal bones, the direction of
the axis of the bony cavity of the ear, and lastly the internal
configuration of the whole skull together with the shape of the brain.

VERTEBRAE.

(FIGURE 37. SIXTH CERVICAL VERTEBRA, natural size, viewed laterally. A.
Wild Gallus bankiva. B. Cochin cock.)

In G. bankiva there are fourteen cervical, seven dorsal with ribs,
apparently fifteen lumbar and sacral, and six caudal vertebrae (7/71. It
appears that I have not correctly designated the several groups of
vertebrae, for a great authority, Mr. W.K. Parker ('Transact. Zoolog. Soc.'
volume 5 page 198) specifies 16 cervical, 4 dorsal, 15 lumbar, and 6 caudal
vertebrae in this genus. But I have used the same terms in all the
following descriptions.); but the lumbar and sacral are so much anchylosed
that I am not sure of their number, and this makes the comparison of the
total number of vertebrae in the several breeds difficult. I have spoken of
six caudal vertebrae, because the basal one is almost completely anchylosed
with the pelvis; but if we consider the number as seven, the caudal
vertebrae agree in all the skeletons. The cervical vertebrae are, as just
stated, in appearance fourteen; but out of twenty-three skeletons in a fit
state for examination, in five of them, namely, in two Games, in two
pencilled Hamburghs, and in a Polish, the fourteenth vertebra bore ribs,
which, though small, were perfectly developed with a double articulation.
The presence of these little ribs cannot be considered as a fact of much
importance, for all the cervical vertebrae bear representatives of ribs;
but their development in the fourteenth vertebra reduces the size of the
passages in the transverse processes, and makes this vertebra exactly like
the first dorsal vertebra. The addition of these little ribs does not
affect the fourteenth cervical alone, for properly the ribs of the first
true dorsal vertebra are destitute of processes; but in some of the
skeletons in which the fourteenth cervical bore little ribs the first pair
of true ribs had well-developed processes. When we know that the sparrow
has only nine, and the swan twenty-three cervical vertebrae (7/72.
Macgillivray 'British Birds' volume 1 page 25.), we need feel no surprise
at the number of the cervical vertebrae in the fowl being, as it appears,
variable.

There are seven dorsal vertebrae bearing ribs; the first dorsal is never
anchylosed with the succeeding four, which are generally anchylosed
together. In one Sultan fowl, however, the two first dorsal vertebrae were
free. In two skeletons, the fifth dorsal was free; generally the sixth is
free (as in G. bankiva), but sometimes only at its posterior end, where in
contact with the seventh. The seventh dorsal vertebra, in every case
excepting in one Spanish cock, was anchylosed with the lumbar vertebrae. So
that the degree to which these middle dorsal vertebrae are anchylosed is
variable.

Seven is the normal number of true ribs, but in two skeletons of the Sultan
fowl (in which the fourteenth cervical vertebra was not furnished with
little ribs) there were eight pairs; the eighth pair seemed to be developed
on a vertebra corresponding with the first lumbar in G. bankiva; the
sternal portion of both the seventh and eighth ribs did not reach the
sternum. In four skeletons in which ribs were developed on the fourteenth
cervical vertebra, there were, when these cervical ribs are included, eight
pairs; but in one Game cock, in which the fourteenth cervical was furnished
with ribs, there were only six pairs of true dorsal ribs; the sixth pair in
this case did not have processes, and thus resembled the seventh pair in
other skeletons; in this Game cock, as far as could be judged from the
appearance of the lumbar vertebrae, a whole dorsal vertebra with its ribs
was missing. We thus see that the ribs (whether or not the little pair
attached to the fourteenth cervical vertebra be counted) vary from six to
eight pair. The sixth pair is frequently not furnished with processes. The
sternal portion of the seventh pair is extremely broad in Cochins, and is
completely ossified. As previously stated, it is scarcely possible to count
the lumbo-sacral vertebrae; but they certainly do not correspond in shape
or number in the several skeletons. The caudal vertebrae are closely
similar in all the skeletons, the only difference being whether or not the
basal one is anchylosed to the pelvis; they hardly vary even in length, not
being shorter in Cochins, with their short tail-feathers, than in other
breeds; in a Spanish cock, however, the caudal vertebrae were a little
elongated. In three rumpless fowls the caudal vertebrae were few in number,
and anchylosed together into a misformed mass.

In the individual vertebrae the differences in structure are very slight.
In the atlas the cavity for the occipital condyle is either ossified into a
ring, or is, as in Bankiva, open on its upper margin. The upper arc of the
spinal canal is a little more arched in Cochins, in conformity with
the shape of the occipital foramen, than in G. bankiva. In several
skeletons a difference, but not of much importance, may be observed, which
commences at the fourth cervical vertebra, and is greatest at about the
sixth, seventh, or eighth vertebra; this consists in the haemal descending
processes being united to the body of the vertebra by a sort of buttress.
This structure may be observed in Cochins, Polish, some Hamburghs, and
probably other breeds; but is absent, or barely developed, in Game,
Dorking, Spanish, Bantam, and several other breeds examined by me. On the
dorsal surface of the sixth cervical vertebra in Cochins three prominent
points are more strongly developed than in the corresponding vertebra of
the Game fowl or G. bankiva.

PELVIS.

This differs in some few points in the several skeletons. The anterior
margin of the ilium seems at first to vary much in outline, but this is
chiefly due to the degree to which the margin in the middle part is
ossified to the crest of the vertebrae; the outline, however, does differ
in being more truncated in Bantams, and more rounded in certain breeds, as
in Cochins. The outline of the ischiadic foramen differs considerably,
being nearly circular in Bantams, instead of egg-shaped as in the Bankiva,
and more regularly oval in some skeletons, as in the Spanish. The obturator
notch is also much less elongated in some skeletons than in others. The end
of the pubic bone presents the greatest difference; being hardly enlarged
in the Bankiva; considerably and gradually enlarged in Cochins, and in a
lesser degree in some other breeds; and abruptly enlarged in Bantams. In
one Bantam this bone extended very little beyond the extremity of the
ischium. The whole pelvis in this latter bird differed widely in its
proportions, being far broader proportionally to its length than in
Bankiva.

(FIGURE 38. EXTREMITY OF THE FURCULA, of natural size, viewed laterally. A.
Wild Gallus bankiva. B. Spangled Polish Fowl. C. Spanish Fowl. D. Dorking
Fowl.)

STERNUM.

This bone is generally so much deformed that it is scarcely possible to
compare its shape strictly in the several breeds. The form of the
triangular extremity of the lateral processes differs considerably, being
either almost equilateral or much elongated. The front margin of the crest
is more or less perpendicular and varies greatly, as does the curvature of
the posterior end, and the flatness of the lower surface. The outline of
the manubrial process also varies, being wedge-shaped in the Bankiva, and
rounded in the Spanish breed. The FURCULUM differs in being more or less
arched, and greatly, as may be seen in the accompanying outlines, in the
shape of the terminal plate; but the shape of this part differed a little
in two skeletons of the wild Bankiva. The CORACOID presents no difference
worth notice. The SCAPULA varies in shape, being of nearly uniform breadth
in Bankiva, much broader in the middle in the Polish fowl, and abruptly
narrowed towards the apex in the two Sultan fowls.

I carefully compared each separate bone of the leg and wing, relatively to
the same bones in the wild Bankiva, in the following breeds, which I
thought were the most likely to differ; namely, in Cochin, Dorking,
Spanish, Polish, Burmese Bantam, Frizzled Indian, and black-boned Silk
fowls; and it was truly surprising to see how absolutely every process,
articulation, and pore agreed, though the bones differed greatly in size.
The agreement is far more absolute than in other parts of the skeleton. In
stating this, I do not refer to the relative thickness and length of the
several bones; for the tarsi varied considerably in both these respects.
But the other limb-bones varied little even in relative length.]

Finally, I have not examined a sufficient number of skeletons to say
whether any of the foregoing differences, except in the skull, are
characteristic of the several breeds. Apparently some differences are more
common in certain breeds than in others,--as an additional rib to the
fourteenth cervical vertebra in Hamburghs and Games, and the breadth of the
end of the pubic bone in Cochins. Both skeletons of the Sultan fowl had
eight dorsal vertebrae, and the end of the scapula in both was somewhat
attenuated. In the skull, the deep medial furrow in the frontal bones and
the vertically elongated occipital foramen seem to be characteristic of
Cochins; as is the great breadth of the frontal bones in Dorkings; the
separation and open spaces between the tips of the ascending branches of
the premaxillaries and nasal bones, as well as the front part of the skull
being but little depressed, characterise Hamburghs; the globular shape of
the posterior part of the skull seems to be characteristic of laced
Bantams; and lastly, the protuberance of the skull with the ascending
branches of the premaxillaries partially aborted, together with the other
differences before specified, are eminently characteristic of Polish and
other Crested fowls.

But the most striking result of my examination of the skeleton is the great
variability of all the bones except those of the extremities. To a certain
extent we can understand why the skeleton fluctuates so much in structure;
fowls have been exposed to unnatural conditions of life, and their whole
organisation has thus been rendered variable; but the breeder is quite
indifferent to, and never intentionally selects, any modification in the
skeleton. External characters, if not attended to by man, such as the
number of the tail and wing feathers and their relative lengths, which in
wild birds are generally constant,--fluctuate in our domestic fowls in the
same manner as the several parts of the skeleton. An additional toe is a
"point" in Dorkings, and has become a fixed character, but is variable in
Cochins and Silk fowls. The colour of the plumage and the form of the comb
are in most breeds, or even sub-breeds, eminently fixed characters; but in
Dorkings these points have not been attended to, and are variable. When any
modification in the skeleton is related to some external character which
man values, it has been, unintentionally on his part, acted on by
selection, and has become more or less fixed. We see this in the wonderful
protuberance of the skull, which supports the crest of feathers in Polish
fowls, and which by correlation has affected other parts of the skull. We
see the same result in the two protuberances which support the horns in the
horned fowl, and in the flattened shape of the front of the skull in
Hamburghs consequent on their flattened and broad "rose-combs." We know not
in the least whether additional ribs, or the changed outline of the
occipital foramen, or the changed form of the scapula, or of the extremity
of the furculum, are in any way correlated with other structures, or have
arisen from the changed conditions and habits of life to which our fowls
have been subjected; but there is no reason to doubt that these various
modifications in the skeleton could be rendered, either by direct
selection, or by the selection of correlated structures, as constant and as
characteristic of each breed, as are the size and shape of the body, the
colour of the plumage, and the form of the comb.

[EFFECTS OF THE DISUSE OF PARTS.

Judging from the habits of our European gallinaceous birds, Gallus bankiva
in its native haunts would use its legs and wings more than do our domestic
fowls, which rarely fly except to their roosts. The Silk and the Frizzled
fowls, from having imperfect wing-feathers, cannot fly at all; and there is
reason to believe that both these breeds are ancient, so that their
progenitors during many generations cannot have flown. The Cochins, also,
from their short wings and heavy bodies, can hardly fly up to a low perch.
Therefore in these breeds, especially in the two first, a considerable
diminution in the wing-bones might have been expected, but this is not the
case. In every specimen, after disarticulating and cleaning the bones, I
carefully compared the relative length of the two main bones of the wing to
each other, and of the two main bones of the leg to each other, with those
of G. bankiva; and it was surprising to see (except in the case of the
tarsi) how exactly the same relative length had been retained. This fact is
curious, from showing how truly the proportions of an organ may be
inherited, although not fully exercised during many generations. I then
compared in several breeds the length of the femur and tibia with the
humerus and ulna, and likewise these same bones with those of G. bankiva;
the result was that the wing-bones in all the breeds (except the Burmese
Jumper, which has unnaturally short legs, are slightly shortened relatively
to the leg-bones; but the decrease is so slight that it may be due to the
standard specimen of G. bankiva having accidentally had wings of slightly
greater length than usual; so that the measurements are not worth giving.
But it deserves notice that the Silk and Frizzled fowls, which are quite
incapable of flight, had their wings LESS reduced relatively to their legs
than in almost any other breed! We have seen with domesticated pigeons that
the bones of the wings are somewhat reduced in length, whilst the primary
feathers are rather increased in length, and it is just possible, though
not probable, that in the Silk and Frizzled fowls any tendency to decrease
in the length of the wing-bones from disuse may have been checked through
the law of compensation, by the decreased growth of the wing-feathers, and
consequent increased supply of nutriment. The wing-bones, however, in both
these breeds, are found to be slightly reduced in length when judged by the
standard of the length of the sternum or head, relatively to these same
parts in G. bankiva.

The actual weight of the main bones of the leg and wing in twelve breeds is
given in the two first columns in Table 7.I. The calculated weight of the
wing-bones relatively to the leg-bones, in comparison with the leg and
wing-bones of G. bankiva, are given in the third column,--the weight of the
wing-bones in G. bankiva being called a hundred. (7/73. It may be well to
explain how the calculation has been made for the third column. In G.
bankiva the leg-bones are to the wing-bones as 86 : 54, or as (neglecting
decimals) 100 : 62;-in Cochins as 311 : 162, or as 100 : 52;--in Dorkings
as 557 : 248, or as 100 : 44; and so on for the other breeds. We thus get
the series of 62, 52, 44 for the relative weights of the wing-bones in G.
bankiva, Cochins, Dorkings, etc. And now taking 100, instead of 62, for the
weight of the wing-bones in G. bankiva, we get, by another rule of three,
83 as the weight of the wing-bones in Cochins; 70 in the Dorkings; and so
on for the remainder of the third column in the table.)

TABLE 7.I. (Weights in grains.)

COLUMN 1. Actual Weight of Femur and Tibia.

COLUMN 2. Actual Weight of Humerus and Ulna.

COLUMN 3. Weight of Wing-bones relatively to the Leg-bones in comparison
with these same bones in Gallus bankiva.

1. 2. 3.

Gallus bankiva -- wild male 86 54 100

1. Cochin -- male 311 162 83
2. Dorking -- male 557 248 70
3. Spanish (Minorca) -- male 386 183 75
4. Gold-Spangled Polish -- male 306 145 75
5. Game, black-breasted -- male 293 143 77
6. Malay -- female 231 116 80
7. Sultan -- male 189 94 79
8. Indian Frizzled -- male 206 88 67
9. Burmese Jumper -- female 53 36 108
10. Hamburgh (pencilled) -- male 157 104 106
11. Hamburgh (pencilled) -- female 114 77 108
12. Silk (black-boned) -- female 88 57 103

In the eight first birds, belonging to distinct breeds, in this table, we
see a decided reduction in the weight of the bones of the wing.

In the Indian Frizzled fowl, which cannot fly, the reduction is carried to
the greatest extent, namely, to thirty-three per cent of their proper
proportional weight. In the next four birds, including the Silk hen, which
is incapable of flight, we see that the wings, relatively to the legs, are
slightly increased in weight; but it should be observed that, if in these
birds the legs had become from any cause reduced in weight, this would give
the false appearance of the wings having increased in relative weight. Now
a reduction of this nature has certainly occurred with the Burmese Jumper,
in which the legs are abnormally short, and in the two Hamburghs and Silk
fowl, the legs, though not short, are formed of remarkably thin and light
bones. I make these statements, not judging by mere eyesight, but after
having calculated the weights of the leg-bones relatively to those of G.
bankiva, according to the only two standards of comparison which I could
use, namely, the relative lengths of the head and sternum; for I do not
know the weight of the body in G. bankiva, which would have been a better
standard. According to these standards, the leg-bones in these four fowls
are in a marked manner far lighter than in any other breed. It may
therefore be concluded that in all cases in which the legs have not been
through some unknown cause much reduced in weight, the wing-bones have
become reduced in weight relatively to the leg-bones, in comparison with
those of G. bankiva. And this reduction of weight may, I apprehend, safely
be attributed to disuse.

To make Table 7.I. quite satisfactory, it ought to have been shown that in
the eight first birds the leg-bones have not actually increased in weight
out of due proportion with the rest of the body; this I cannot show, from
not knowing, as already remarked, the weight of the wild Bankiva. (7/74.
Mr. Blyth (in 'Annals and Mag. of Nat. Hist.' 2nd series volume 1 1848 page
456) gives 3 1/4 pounds as the weight of a full-grown male G. bankiva; but
from what I have seen of the skins and skeletons of various breeds, I
cannot believe that my two specimens of G. bankiva could have weighed so
much.) I am indeed inclined to suspect that the leg-bones in the Dorking,
No. 2 in the table, are proportionally too heavy; but this bird was a very
large one, weighing 7 pounds 2 ounces, though very thin. Its leg-bones were
more than ten times as heavy as those of the Burmese Jumper! I tried to
ascertain the length both of the leg-bones and wing-bones relatively to
other parts of the body and skeleton: but the whole organisation in these
birds, which have been so long domesticated, has become so variable, that
no certain conclusions could be reached. For instance, the legs of the
above Dorking cock were nearly three-quarters of an inch too short
relatively to the length of the sternum, and more than three-quarters of an
inch too long relatively to the length of the skull, in comparison with
these same parts in G. bankiva.

TABLE 7.II.

COLUMN 1. Length of Sternum (in inches and decimals.)

COLUMN 2. Depth of Crest of Sternum (in inches and decimals.).

COLUMN 3. Depth of Crest relatively to the length of the Sternum, in
comparison with Gallus bankiva.

1. 2. 3.

Gallus bankiva -- male. 4.20 1.40 100

1. Cochin -- male. 5.83 1.55 78
2. Dorking -- male. 6.95 1.97 84
3. Spanish -- male. 6.10 1.83 90
4. Polish -- male. 5.07 1.50 87
5. Game -- male. 5.55 1.55 81
6. Malay -- female. 5.10 1.50 87
7. Sultan -- male. 4.47 1.36 90
8. Frizzled hen -- male. 4.25 1.20 84
9. Burmese Jumper -- female. 3.06 0.85 81
10. Hamburgh -- male. 5.08 1.40 81
11. Hamburgh -- female. 4.55 1.26 81
12. Silk fowl -- female. 4.49 1.01 66

In Table 7.II. in the two first columns we see in inches and decimals the
length of the sternum, and the extreme depth of its crest to which the
pectoral muscles are attached. In the third column we have the calculated
depth of the crest, relatively to the length of the sternum, in comparison
with these same parts in G. bankiva. (7/75. The third column is calculated
on the same principle as explained in footnote 7/73 above.)

By looking to the third column we see that in every case the depth of the
crest relatively to the length of the sternum, in comparison with G.
bankiva, is diminished, generally between 10 and 20 per cent. But the
degree of reduction varies much, partly in consequence of the frequently
deformed state of the sternum. In the Silk fowl, which cannot fly, the
crest is 34 per cent less deep than what it ought to have been. This
reduction of the crest in all the breeds probably accounts for the great
variability, before referred to, in the curvature of the furculum, and in
the shape of its sternal extremity. Medical men believe that the abnormal
form of the spine so commonly observed in women of the higher ranks results
from the attached muscles not being fully exercised. So it is with our
domestic fowls, for they use their pectoral muscles but little, and, out of
twenty-five sternums examined by me, three alone were perfectly
symmetrical, ten were moderately crooked, and twelve were deformed to an
extreme degree. Mr. Romanes, however, believes that the malformation is due
to fowls whilst young resting their sternums on the sticks on which they
roost.]

Finally, we may conclude with respect to the various breeds of the fowl,
that the main bones of the wing have probably been shortened in a very
slight degree; that they have certainly become lighter relatively to the
leg-bones in all the breeds in which these latter bones are not unnaturally
short or delicate; and that the crest of the sternum, to which the pectoral
muscles are attached, has invariably become less prominent, the whole
sternum being also extremely liable to deformity. These results we may
attribute to the lessened use of the wings.

CORRELATION OF GROWTH.

I will here sum up the few facts which I have collected on this obscure,
but important, subject. In Cochin and Game fowls there is perhaps some
relation between the colour of the plumage and the darkness of the egg-
shell. In Sultans the additional sickle-feathers in the tail are apparently
related to the general redundancy of the plumage, as shown by the feathered
legs, large crest, and beard. In two tailless fowls which I examined the
oil-gland was aborted. A large crest of feathers, as Mr. Tegetmeier has
remarked, seems always accompanied by a great diminution or almost entire
absence of the comb. A large beard is similarly accompanied by diminished
or absent wattles. These latter cases apparently come under the law of
compensation or balancement of growth. A large beard beneath the lower jaw
and a large top-knot on the skull often go together. The comb when of any
peculiar shape, as with Horned, Spanish, and Hamburgh fowls, affects in a
corresponding manner the underlying skull; and we have seen how wonderfully
this is the case with Crested fowls when the crest is largely developed.
With the protuberance of the frontal bones the shape of the internal
surface of the skull and of the brain is greatly modified. The presence of
a crest influences in some unknown way the development of the ascending
branches of the premaxillary bone, and of the inner processes of the nasal
bones; and likewise the shape of the external orifice of the nostrils.
There is a plain and curious correlation between a crest of feathers and
the imperfectly ossified condition of the skull. Not only does this hold
good with nearly all crested fowls, but likewise with tufted ducks, and as
Dr. Gunther informs me with tufted geese in Germany.

Lastly, the feathers composing the crest in male Polish fowls resemble
hackles, and differ greatly in shape from those in the crest of the female.
The neck, wing-coverts, and loins in the male bird are properly covered
with hackles, and it would appear that feathers of this shape have spread
by correlation to the head of the male. This little fact is interesting;
because, though both sexes of some wild gallinaceous birds have their heads
similarly ornamented, yet there is often a difference in the size and shape
of feathers forming their crests. Furthermore, there is in some cases, as
in the male Gold and in the male Amherst pheasants (P. pictus and
amherstiae), a close relation in colour, as well as in structure, between
the plumes on the head and on the loins. It would therefore appear that the
same law has regulated the state of the feathers on the head and body, both
with species living under natural conditions, and with birds which have
varied under domestication.


CHAPTER 1.VIII.

DUCK--GOOSE--PEACOCK--TURKEY--GUINEA-FOWL--CANARY-BIRD--GOLD-FISH--HIVE-
BEES--SILK-MOTHS.

DUCKS, SEVERAL BREEDS OF.
PROGRESS OF DOMESTICATION.
ORIGIN OF FROM THE COMMON WILD-DUCK.
DIFFERENCES IN THE DIFFERENT BREEDS.
OSTEOLOGICAL DIFFERENCES.
EFFECTS OF USE AND DISUSE ON THE LIMB-BONES.

GOOSE, ANCIENTLY DOMESTICATED.
LITTLE VARIATION OF.
SEBASTOPOL BREED.

PEACOCK, ORIGIN OF BLACK-SHOULDERED BREED.

TURKEY, BREEDS OF.
CROSSED WITH THE UNITED STATES SPECIES.
EFFECTS OF CLIMATE ON.

GUINEA-FOWL, CANARY-BIRD, GOLD-FISH, HIVE-BEES.

SILK-MOTHS, SPECIES AND BREEDS OF.
ANCIENTLY DOMESTICATED.
CARE IN THEIR SELECTION.
DIFFERENCES IN THE DIFFERENT RACES.
IN THE EGG, CATERPILLAR, AND COCOON STATES.
INHERITANCE OF CHARACTERS.
IMPERFECT WINGS.
LOST INSTINCTS.
CORRELATED CHARACTERS.

I will, as in previous cases, first briefly describe the chief domestic
breeds of the duck:--

[BREED 1. COMMON DOMESTIC DUCK.

Varies much in colour and in proportions, and differs in instincts and
disposition from the wild duck. There are several sub-breeds:--

1. The Aylesbury, of great size, white, with pale-yellow beak and legs;
abdominal dermal sack largely developed.

2. The Rouen, of great size, coloured like the wild duck, with green or
mottled beak; dermal sack largely developed.

3. Tufted Duck, with a large top-knot of fine downy feathers, supported on
a fleshy mass, with the skull perforated beneath. The top-knot in a duck
which I imported from Holland was two and a half inches in diameter.

4. Labrador (or Canadian, or Buenos Ayres, or East Indian); plumage
entirely black; beak broader, relatively to its length, than in the wild
duck; eggs slightly tinted with black. This sub-breed perhaps ought to be
ranked as a breed; it includes two sub-varieties, one as large as the
common domestic duck, which I have kept alive, and the other smaller and
often capable of flight. (8/1. 'Poultry Chronicle' 1854 volume 2 page 91
and volume 1 page 330.) I presume it is this latter sub-variety which has
been described in France (8/2. Dr. Turral 'Bull. Soc. d'Acclimat.' tome 7
1860 page 541.) as flying well, being rather wild, and when cooked having
the flavour of the wild duck; nevertheless this sub-variety is polygamous,
like other domesticated ducks and unlike the wild duck. These black
Labrador ducks breed true; but a case is given by Dr. Turral of the French
sub-variety producing young with some white feathers on the head and neck,
and with an ochre-coloured patch on the breast.

BREED 2. HOOK-BILLED DUCK.

This bird presents an extraordinary appearance from the downward curvature
of the beak. The head is often tufted. The common colour is white, but some
are coloured like wild ducks. It is an ancient breed, having been noticed
in 1676. (8/3. Willughby's 'Ornithology' by Ray page 381. This breed is
also figured by Albin in 1734 in his 'Nat. Hist. of Birds' volume 2 page
86.) It shows its prolonged domestication by almost incessantly laying
eggs, like the fowls which are called everlasting layers. (8/4. F. Cuvier
in 'Annales du Museum' tome 9 page 128 says that moulting and incubation
alone stops these ducks laying. Mr. B.P. Brent makes a similar remark in
the 'Poultry Chronicle' 1855 volume 3 page 512.)

BREED 3. CALL DUCK.

Remarkable from its small size, and from the extraordinary loquacity of the
female. Beak short. These birds are either white, or coloured like the wild
duck.

BREED 4. PENGUIN DUCK.

This is the most remarkable of all the breeds, and seems to have originated
in the Malayan archipelago. It walks with its body extremely erect, and
with its thin neck stretched straight upwards. Beak rather short. Tail
upturned, including only 18 feathers. Femur and metatarsus elongated.]

Almost all naturalists admit that the several breeds are descended from the
common wild duck (Anas boschas); most fanciers, on the other hand, take as
usual a very different view. (8/5. Rev. E.S. Dixon 'Ornamental and Domestic
Poultry' 1848 page 117. Mr. B.P. Brent in 'Poultry Chronicle' volume 3 1855
page 512.) Unless we deny that domestication, prolonged during centuries,
can affect even such unimportant characters as colour, size, and in a
slight degree proportional dimensions and mental disposition, there is no
reason whatever to doubt that the domestic duck is descended from the
common wild species, for the one differs from the other in no important
character. We have some historical evidence with respect to the period and
progress of the domestication of the duck. It was unknown (8/6. Crawfurd on
the 'Relation of Domesticated Animals to Civilisation' read before the
Brit. Assoc. at Oxford 1860.) to the ancient Egyptians, to the Jews of the
Old Testament, and to the Greeks of the Homeric period. About eighteen
centuries ago Columella (8/7. Dureau de La Malle in 'Annales des Sciences
Nat.' tome 17 page 164; and tome 21 page 55. Rev. E.S. Dixon 'Ornamental
Poultry' page 118. Tame ducks were not known in Aristotle's time, as
remarked by Volz in his 'Beitrage zur Kulturgeschichte' 1852 s. 78.) and
Varro speak of the necessity of keeping ducks in netted enclosures like
other wild fowl, so that at this period there was danger of their flying
away. Moreover, the plan recommended by Columella to those who wish to
increase their stock of ducks, namely, to collect the eggs of the wild bird
and to place them under a hen, shows, as Mr. Dixon remarks, "that the duck
had not at this time become a naturalised and prolific inmate of the Roman
poultry-yard." The origin of the domestic duck from the wild species is
recognised in nearly every language of Europe, as Aldrovandi long ago
remarked, by the same name being applied to both. The wild duck has a wide
range from the Himalayas to North America. It crosses readily with the
domestic bird, and the crossed offspring are perfectly fertile.

Both in North America and Europe the wild duck has been found easy to tame
and breed. In Sweden this experiment was carefully tried by Tiburtius; he
succeeded in rearing wild ducks for three generations, but, though they
were treated like common ducks, they did not vary even in a single feather.
The young birds suffered from being allowed to swim about in cold water
(8/8. I quote this account from 'Die Enten- und Schwanenzucht' Ulm 1828 s.
143. See Audubon 'Ornithological Biography' volume 3 page 168 on the taming
of ducks on the Mississippi. For the same fact in England see Mr. Waterton
in Loudon's 'Mag. of Nat. Hist.' volume 8 1835 page 542; and Mr. St. John
'Wild Sports and Nat. Hist. of the Highlands' 1846 page 129.), as is known
to be the case, though the fact is a strange one, with the young of the
common domestic duck. An accurate and well-known observer in England (8/9.
Mr. E. Hewitt in 'Journal of Horticulture' 1862 page 773; and 1863 page
39.) has described in detail his often repeated and successful experiments
in domesticating the wild duck. Young birds are easily reared from eggs
hatched under a bantam; but to succeed it is indispensable not to place the
eggs of both the wild and tame duck under the same hen, for in this case
"the young wild ducks die off, leaving their more hardy brethren in
undisturbed possession of their foster-mother's care. The difference of
habit at the onset in the newly-hatched ducklings almost entails such a
result to a certainty." The wild ducklings were from the first quite tame
towards those who took care of them as long as they wore the same clothes,
and likewise to the dogs and cats of the house. They would even snap with
their beaks at the dogs, and drive them away from any spot which they
coveted. But they were much alarmed at strange men and dogs. Differently
from what occurred in Sweden, Mr. Hewitt found that his young birds always
changed and deteriorated in character in the course of two or three
generations; notwithstanding that great care was taken to prevent their
crossing with tame ducks. After the third generation his birds lost the
elegant carriage of the wild species, and began to acquire the gait of the
common duck. They increased in size in each generation, and their legs
became less fine. The white collar round the neck of the mallard became
broader and less regular, and some of the longer primary wing-feathers
became more or less white. When this occurred, Mr. Hewitt destroyed nearly
the whole of his stock and procured fresh eggs from wild nests; so that he
never bred the same family for more than five or six generations. His birds
continued to pair together, and never became polygamous like the common
domestic duck. I have given these details, because no other case, as far as
I know, has been so carefully recorded by a competent observer of the
progress of change in wild birds reared for several generations in a
domestic condition.

From these considerations there can hardly be a doubt that the wild duck is
the parent of the common domestic kind; nor need we look to other species
for the parentage of the more distinct breeds, namely, Penguin, Call, Hook-
billed, Tufted, and Labrador ducks. I will not repeat the arguments used in
the previous chapters on the improbability of man having in ancient times
domesticated several species since become unknown or extinct, though ducks
are not readily exterminated in the wild state;--on some of the supposed
parent-species having had abnormal characters in comparison with all the
other species of the genus, as with Hook-billed and Penguin ducks;--on all
the breeds, as far as is known being fertile together (8/10. I have met
with several statements on the fertility of the several breeds when
crossed. Mr. Yarrell assured me that Call and common ducks are perfectly
fertile together. I crossed Hook-billed and common ducks, and a Penguin and
Labrador, and the crossed Ducks were quite fertile, though they were not
bred inter se, so that the experiment was not fully tried. Some half-bred
Penguins and Labradors were again crossed with Penguins, and subsequently
bred by me inter se, and they were extremely fertile.);--on all the breeds
having the same general disposition, instinct, etc. But one fact bearing on
this question may be noticed: in the great duck family, one species alone,
namely, the male of A. boschas, has its four middle tail-feathers curled
upwardly; now in every one of the above-named domestic breeds these curled
feathers exist, and on the supposition that they are descended from
distinct species, we must assume that man formerly hit upon species all of
which had this now unique character. Moreover, sub-varieties of each breed
are coloured almost exactly like the wild duck, as I have seen with the
largest and smallest breeds, namely Rouens and Call ducks, and, as Mr.
Brent states (8/11. 'Poultry Chronicle' 1855 volume 3 page 512.), is the
case with Hook-billed ducks. This gentleman, as he informs me, crossed a
white Aylesbury drake and a black Labrador duck, and some of the ducklings
as they grew up assumed the plumage of the wild duck.

With respect to Penguins, I have not seen many specimens, and none were
coloured precisely like the wild duck; but Sir James Brooke sent me three
skins from Lombok and Bali, in the Malayan archipelago; the two females
were paler and more rufous than the wild duck, and the drake differed in
having the whole under and upper surface (excepting the neck, tail-coverts,
tail, and wings) silver-grey, finely pencilled with dark lines, closely
like certain parts of the plumage of the wild mallard. But I found this
drake to be identical in every feather with a variety of the common breed
procured from a farm-yard in Kent, and I have occasionally elsewhere seen
similar specimens. The occurrence of a duck bred under so peculiar a
climate as that of the Malayan archipelago, where the wild species does not
exist, with exactly the same plumage as may occasionally be seen in our
farm-yards, is a fact worth notice. Nevertheless the climate of the Malayan
archipelago apparently tends to cause the duck to vary much, for Zollinger
(8/12. 'Journal of the Indian Archipelago' volume 5 page 334.), speaking of
the Penguin breed, says that in Lombok "there is an unusual and very
wonderful variety of ducks." One Penguin drake which I kept alive differed
from those of which the skins were sent me from Lombok, in having its
breast and back partially coloured with chestnut-brown, thus more closely
resembling the Mallard.

From these several facts, more especially from the drakes of all the breeds
having curled tail-feathers, and from certain sub-varieties in each breed
occasionally resembling in general plumage the wild duck, we may conclude
with confidence that all the breeds are descended from A. boschas.

[I will now notice some of the peculiarities characteristic of the several
breeds. The eggs vary in colour; some common ducks laying pale-greenish and
others quite white eggs. The eggs which are first laid during each season
by the black Labrador duck, are tinted black, as if rubbed with ink. A good
observer assured me that one year his ducks of this breed laid almost
perfectly white eggs. Another curious case shows what singular variations
sometimes occur and are inherited; Mr. Hansell (8/13. 'The Zoologist'
volumes 7, 8 1849-1850 page 2353.) relates that he had a common duck which
always laid eggs with the yolk of a dark-brown colour like melted glue; and
the young ducks, hatched from these eggs, laid the same kind of eggs, so
that the breed had to be destroyed.

(FIGURE 39. SKULLS, viewed laterally, reduced to two-thirds of the natural
size. A. Wild Duck. B. Hook-billed Duck.)

The Hook-billed duck is highly remarkable (see figure 39, of skull); and
its peculiar beak has been inherited at least since the year 1676. This
structure is evidently analogous with that described in the Bagadotten
carrier pigeon. Mr. Brent (8/14. 'Poultry Chronicle' 1855 volume 3 page
512.) says that, when Hook-billed ducks are crossed with common ducks,
"many young ones are produced with the upper mandible shorter than the
lower, which not unfrequently causes the death of the bird." With ducks a
tuft of feathers on the head is by no means a rare occurrence; namely, in
the True-tufted breed, the Hook-billed, the common farm-yard kind, and in a
duck having no other peculiarity which was sent to me from the Malayan
archipelago. The tuft is only so far interesting as it affects the skull,
which is thus rendered slightly more globular, and is perforated by
numerous apertures. Call ducks are remarkable from their extraordinary
loquacity: the drake only hisses like common drakes; nevertheless, when
paired with the common duck, he transmits to his female offspring a strong
quacking tendency. This loquacity seems at first a surprising character to
have been acquired under domestication. But the voice varies in the
different breeds; Mr. Brent (8/15. 'Poultry Chronicle' volume 3 1855 page
312. With respect to Rouens see ditto volume 1 1854 page 167.) says that
Hook-billed ducks are very loquacious, and that Rouens utter a "dull, loud,
and monotonous cry, easily distinguishable by an experienced ear." As the
loquacity of the Call duck is highly serviceable, these birds being used in
decoys, this quality may have been increased by selection. For instance,
Colonel Hawker says, if young wild ducks cannot be got for a decoy, "by way
of make-shift, SELECT tame birds which are the most clamorous, even if
their colour should not be like that of wild ones." (8/16. Col. Hawker
'Instructions to young Sportsmen' quoted by Mr. Dixon in his 'Ornamental
Poultry' page 125.) It has been erroneously asserted that Call ducks hatch
their eggs in less time than common ducks. (8/17. 'Cottage Gardener' April
9, 1861.)

The Penguin duck is the most remarkable of all the breeds; the thin neck
and body are carried erect; the wings are small; the tail is upturned; and
the thigh-bones and metatarsi are considerably lengthened in proportion
with the same bones in the wild duck. In five specimens examined by me
there were only eighteen tail-feathers instead of twenty as in the wild
duck; but I have also found only eighteen and nineteen tail-feathers in two
Labrador ducks. On the middle toe, in three specimens, there were twenty-
seven or twenty-eight scutellae, whereas in two wild ducks there were
thirty-one and thirty-two. The Penguin when crossed transmits with much
power its peculiar form of body and gait to its offspring; this was
manifest with some hybrids raised in the Zoological Gardens between one of
these birds and the Egyptian goose (Anser aegyptiacus) (8/18. These hybrids
have been described by M. Selys-Longchamps in the 'Bulletins (tome 12 No
10) Acad. Roy. de Bruxelles.'), and likewise with some mongrels which I
raised between the Penguin and Labrador duck. I am not much surprised that
some writers should maintain that this breed must be descended from an
unknown and distinct species; but from the reasons already assigned, it
seems to me far more probable that it is the descendant, much modified by
domestication under an unnatural climate, of Anas boschas.

OSTEOLOGICAL CHARACTERS.

The skulls of the several breeds differ from each other and from the skull
of the wild duck in very little except in the proportional length and
curvature of the premaxillaries. These latter bones in the Call duck are
short, and a line drawn from their extremities to the summit of the skull
is nearly straight, instead of being concave as in the common duck; so that
the skull resembles that of a small goose. In the Hook-billed duck (figure
39), these same bones as well as the lower jaw curve downwards in a most
remarkable manner, as represented. In the Labrador duck the premaxillaries
are rather broader than in the wild duck; and in two skulls of this breed
the vertical ridges on each side of the supra-occipital bone are very
prominent. In the Penguin the premaxillaries are relatively shorter than in
the wild duck; and the inferior points of the paramastoids more prominent.
In a Dutch tufted duck, the skull under the enormous tuft was slightly more
globular and was perforated by two large apertures; in this skull the
lachrymal bones were produced much further backwards, so as to have a
different shape and nearly to touch the post. lat. processes of the frontal
bones, thus almost completing the bony orbit of the eye. As the quadrate
and pterygoid bones are of such complex shape and stand in relation with so
many other bones, I carefully compared them in all the principal breeds;
but excepting in size they presented no difference.

(FIGURE 40.-CERVICAL VERTEBRA, of natural size. A. Eighth cervical vertebra
of Wild Duck viewed on haemal surface. B. Eighth cervical vertebra of Call
Duck, viewed as above. C. Twelfth cervical vertebra of Wild Duck viewed
laterally. D. Twelfth cervical vertebra of Aylesbury Duck, viewed
laterally.)

VERTEBRAE AND RIBS.

In one skeleton of the Labrador duck there were the usual fifteen cervical
vertebrae and the usual nine dorsal vertebrae bearing ribs; in the other
skeleton there were fifteen cervical and ten dorsal vertebrae with ribs;
nor, as far as could be judged, was this owing merely to a rib having been
developed on the first lumbar vertebra; for in both skeletons the lumbar
vertebrae agreed perfectly in number, shape, and size with those of the
wild duck. In two skeletons of the Call duck there were fifteen cervical
and nine dorsal vertebrae; in a third skeleton small ribs were attached to
the so-called fifteenth cervical vertebra, making ten pairs of ribs; but
these ten ribs do not correspond, or arise from the same vertebra, with the
ten in the above-mentioned Labrador duck. In the Call duck, which had small
ribs attached to the fifteenth cervical vertebra, the haemal spines of the
thirteenth and fourteenth (cervical) and of the seventeenth (dorsal)
vertebrae corresponded with the spines on the fourteenth, fifteenth, and
eighteenth vertebrae of the wild duck: so that each of these vertebrae had
acquired a structure proper to one posterior to it in position. In the
eighth cervical vertebra of this same Call duck (figure 40, B), the two
branches of the haemal spine stand much closer together than in the wild
duck (A), and the descending haemal processes are much shortened. In the
Penguin duck the neck from its thinness and erectness falsely appears (as
ascertained by measurement) to be much elongated, but the cervical and
dorsal vertebrae present no difference; the posterior dorsal vertebrae,
however, are more completely anchylosed to the pelvis than in the wild
duck. The Aylesbury duck has fifteen cervical and ten dorsal vertebrae
furnished with ribs, but the same number of lumbar, sacral, and caudal
vertebrae, as far as could be traced, as in the wild duck. The cervical
vertebrae in this same duck (figure 40, D) were much broader and thicker
relatively to their length than in the wild (C); so much so, that I have
thought it worth while to give a sketch of the twelfth cervical vertebra in
these two birds. From the foregoing statements we see that the fifteenth
cervical vertebra occasionally becomes modified into a dorsal vertebra, and
when this occurs all the adjoining vertebrae are modified. We also see that
an additional dorsal vertebra bearing a rib is occasionally developed, the
number of the cervical and lumbar vertebrae apparently remaining the same
as usual.

I examined the bony enlargement of the trachea in the males of the Penguin,
Call, Hook-billed, Labrador, and Aylesbury breeds; and in all it was
identical in shape.

The PELVIS is remarkably uniform; but in the skeleton of the Hook-billed
duck the anterior part is much bowed inwards; in the Aylesbury and some
other breeds the ischiadic foramen is less elongated. In the sternum,
furculum, coracoids, and scapulae, the differences are so slight and so
variable as not to be worth notice, except that in two skeletons of the
Penguin duck the terminal portion of the scapula was much attenuated.

In the bones of the leg and wing no modification in shape could be
observed. But in the Penguin and Hook-billed ducks, the terminal phalanges
of the wing are a little shortened. In the former, the femur, and
metatarsus (but not the tibia) are considerably lengthened, relatively to
the same bones in the wild duck, and to the wing-bones in both birds. This
elongation of the leg-bones could be seen whilst the bird was alive, and is
no doubt connected with its peculiar upright manner of walking. In a large
Aylesbury duck, on the other hand, the tibia was the only bone of the leg
which relatively to the other bones was slightly lengthened.

ON THE EFFECTS OF THE INCREASED AND DECREASED USE OF THE LIMBS.

In all the breeds the bones of the wing (measured separately after having
been cleaned) relatively to those of the leg have become slightly
shortened, in comparison with the same bones in the wild duck, as may be
seen in Table 8.I.

TABLE 8.I.a.

COLUMN 1. Length of Femur, Tibia, and Metatarsus together (inches).

COLUMN 2. Length of Humerus, Radius, and Metacarpus together (inches).

COLUMN 3. Or as (ratio).

Name of Breed. 1. 2. 3.

Wild mallard. 7.14 9.28 100:129
Aylesbury. 8.64 10.43 100:120
Tufted (Dutch). 8.25 9.83 100:119
Penguin. 7.12 8.78 100:123
Call. 6.20 7.77 100:125

TABLE 8.I.b.

COLUMN 1. Length of Femur, Tibia, and Metatarsus together (inches).

COLUMN 2. Length of all the bones of the wing (inches).

COLUMN 3. Or as (ratio).

Name of Breed. 1. 2. 3.

Wild duck (another specimen). 6.85 10.07 100:147
Common domestic duck. 8.15 11.26 100:138

In table 8.I we see, by comparison with the wild duck, that the reduction
in the length of the bones of the wing, relatively to those of the legs,
though slight, is universal. The reduction is least in the Call duck, which
has the power and the habit of frequently flying.

In weight there is a greater relative difference between the bones of the
leg and wing, as may be seen in Table 8.II:

TABLE 8.II.a.

COLUMN 1. Weight of Femur, Tibia, and Metatarsus (grains).

COLUMN 2. Weight of Humerus, Radius, and Metacarpus (grains).

COLUMN 3. Or as (ratio).

Name of Breed. 1. 2. 3.

Wild mallard. 54 97 100:179
Aylesbury. 164 204 100:124
Hooked-bill. 107 160 100:149
Tufted (Dutch). 111 148 100:133
Penguin. 75 90.5 100:120
Labrador. 141 165 100:117
Call. 57 93 100:163

TABLE 8.II.b.

COLUMN 1. Weight of all the Bones of the Leg and Foot (grains).

COLUMN 2. Weight of all the Bones of the Wing (grains).

COLUMN 3. Or as (ratio).

Name of Breed. 1. 2. 3.

Wild (another specimen). 66 115 100:173
Common domestic duck. 127 158 100:124

In these domesticated birds, the considerably lessened weight of the bones
of the wing (i.e. on an average, twenty-five per cent of their proper
proportional weight), as well as their slightly lessened length, relatively
to the leg-bones, might follow, not from any actual decrease in the wing-
bones, but from the increased weight and length of the bones of the legs.

TABLE 8.III.a.

COLUMN 1. Weight of entire Skeleton (grains). (N.B. One Metatarsus and Foot
was removed from each skeleton, as it had been accidentally lost in two
cases.)

COLUMN 2. Weight of Femur, Tibia, and Metatarsus (grains).

COLUMN 3. Or as (ratio).

Name of Breed. 1. 2. 3.

Wild mallard. 839 54 1000:64
Aylesbury. 1925 164 1000:85
Tufted (Dutch). 1404 111 1000:79
Penguin. 871 75 1000:86
Call (from Mr. Fox). 717 57 1000:79

TABLE 8.III.b.

COLUMN 1. Weight of entire Skeleton (grains). (N.B. One Metatarsus and Foot
was removed from each skeleton, as it had been accidentally lost in two
cases.)

COLUMN 2. Weight of Humerus, Radius and Metacarpus (grains).

COLUMN 3. Or as (ratio).

Name of Breed. 1. 2. 3.

Wild mallard. 839 97 1000:115
Aylesbury. 1925 204 1000:105
Tufted (Dutch). 1404 148 1000:105
Penguin. 871 90 1000:103
Call (from Mr. Baker). 914 100 1000:109
Call (from Mr. Fox). 717 92 1000:129

Table 8.III.a shows that the leg-bones relatively to the weight of the
entire skeleton have really increased in weight; but Table 8.III.b shows
that according to the same standard the wing-bones have also really
decreased in weight; so that the relative disproportion shown in the
foregoing tables between the wing and leg-bones, in comparison with those
of the wild duck, is partly due to the increase in weight and length of the
leg-bones, and partly to the decrease in weight and length of the wing-
bones.

With respect to Tables 8.III.a and b, I may first state that I tested them
by taking another skeleton of a wild duck and of a common domestic duck,
and by comparing the weight of ALL the bones of the leg with ALL those of
the wings, and the result was the same. In the first of these tables we see
that the leg-bones in each case have increased in actual weight. It might
have been expected that, with the increased or decreased weight of the
entire skeleton, the leg-bones would have become proportionally heavier or
lighter; but their greater weight in all the breeds relatively to the other
bones can be accounted for only by these domestic birds having used their
legs in walking and standing much more than the wild, for they never fly,
and the more artificial breeds rarely swim. In the second table we see,
with the exception of one case, a plain reduction in the weight of the
bones of the wing, and this no doubt has resulted from their lessened use.
The one exceptional case, namely, in one of the Call ducks, is in truth no
exception, for this bird was constantly in the habit of flying about; and I
have seen it day after day rise from my grounds, and fly for a long time in
circles of more than a mile in diameter. In this Call duck there is not
only no decrease, but an actual increase in the weight of the wing-bones
relatively to those of the wild-duck; and this probably is consequent on
the remarkable lightness and thinness of all the bones of the skeleton.

Lastly, I weighed the furculum, coracoids, and scapula of a wild duck and
of a common domestic duck, and I found that their weight, relatively to
that of the whole skeleton, was as one hundred in the former to eighty-nine
in the latter; this shows that these bones in the domestic duck have been
reduced eleven per cent of their due proportional weight. The prominence of
the crest of the sternum, relatively to its length, is also much reduced in
all the domestic breeds. These changes have evidently been caused by the
lessened use of the wings.]

It is well known that several birds, belonging to different Orders, and
inhabiting oceanic islands, have their wings greatly reduced in size and
are incapable of flight. I suggested in my 'Origin of Species' that, as
these birds are not persecuted by any enemies, the reduction of their wings
had probably been caused by gradual disuse. Hence, during the earlier
stages of the process of reduction, such birds would probably have
resembled our domesticated ducks in the state of their organs of flight.
This is the case with the water-hen (Gallinula nesiotis) of Tristan
d'Acunha, which "can flutter a little, but obviously uses its legs, and not
its wings, as a mode of escape." Now Mr. Sclater (8/19. 'Proc. Zoolog.
Soc.' 1861 page 261.) finds in this bird that the wings, sternum, and
coracoids are all reduced in length, and the crest of the sternum in depth,
in comparison with the same bones in the European water-hen (G. chloropus).
On the other hand, the thigh-bones and pelvis are increased in length, the
former by four lines, relatively to the same bones in the common water-hen.
Hence in the skeleton of this natural species nearly the same changes have
occurred, only carried a little further, as with our domestic ducks, and in
this latter case I presume no one will dispute that they have resulted from
the lessened use of the wings and the increased use of the legs.

THE GOOSE.

This bird deserves some notice, as hardly any other anciently domesticated
bird or quadruped has varied so little. That geese were anciently
domesticated we know from certain verses in Homer; and from these birds
having been kept (388 B.C.) in the Capitol at Rome as sacred to Juno, which
sacredness implies great antiquity. (8/20. 'Ceylon' by Sir J.E. Tennent
1859 volume 1 page 485; also J. Crawfurd on the 'Relation of Domest.
Animals to Civilisation' read before Brit. Assoc. 1860. See also
'Ornamental Poultry' by Rev. E.S. Dixon 1848 page 132. The goose figured on
the Egyptian monuments seems to have been the Red goose of Egypt.) That the
goose has varied in some degree, we may infer from naturalists not being
unanimous with respect to its wild parent-form; though the difficulty is
chiefly due to the existence of three or four closely allied wild European
species. (8/21. Macgillivray's 'British Birds' volume 4 page 593.) A large
majority of capable judges are convinced that our geese are descended from
the wild Grey-leg goose (Anser ferus); the young of which can easily be
tamed. (8/22. Mr. A. Strickland, 'Annals and Mag. of Nat. Hist.' 3rd series
volume 3 1859 page 122, reared some young wild geese, and found them in
habits and in all characters identical with the domestic goose.) This
species, when crossed with the domestic goose, produced in the Zoological
Gardens, as I was assured in 1849, perfectly fertile offspring. (8/23. See
also Hunter 'Essays' edited by Owen volume 2 page 322.) Yarrell (8/24.
Yarrell's 'British Birds' volume 3 page 142.) has observed that the lower
part of the trachea of the domestic goose is sometimes flattened, and that
a ring of white feathers sometimes surrounds the base of the beak. These
characters seem at first sight good indications of a cross at some former
period with the white-fronted goose (A. albifrons); but the white ring is
variable in this latter species, and we must not overlook the law of
analogous variation; that is, of one species assuming some of the
characters of allied species.

As the goose has proved so little flexible in its organisation under long-
continued domestication, the amount of variation which it has undergone may
be worth giving. It has increased in size and in productiveness (8/25. L.
Lloyd 'Scandinavian Adventures' 1854 volume 2 page 413, says that the wild
goose lays from five to eight eggs, which is a much fewer number than that
laid by our domestic goose.); and varies from white to a dusky colour.
Several observers (8/26. The Rev. L. Jenyns (Blomefield) seems first to
have made this observation in his 'British Animals.' See also Yarrell, and
Dixon in his 'Ornamental Poultry' (page 139), and 'Gardener's Chronicle'
1857 page 45.) have stated that the gander is more frequently white than
the goose, and that when old it almost invariably becomes white; but this
is not the case with the parent-form, the A. ferus. Here, again, the law of
analogous variation may have come into play, as the almost snow-white male
of the Rock goose (Bernicla antarctica) standing on the sea-shore by his
dusky partner is a sight well known to those who have traversed the sounds
of Tierra del Fuego and the Falkland Islands. Some geese have top-knots;
and the skull beneath, as before stated, is perforated. A sub-breed has
lately been formed with the feathers reversed at the back of the head and
neck. (8/27. Mr. Bartlet exhibited the head and neck of a bird thus
characterised before the Zoological Soc. February 1860.) The beak varies a
little in size, and is of a yellower tint than in the wild species; but its
colour and that of the legs are both slightly variable. (8/28. W. Thompson
'Natural Hist. of Ireland' 1851 volume 3 page 31. The Rev. E.S. Dixon gave
me some information on the varying colour of the beak and legs.) This
latter fact deserves attention, because the colour of the legs and beak is
highly serviceable in discriminating the several closely allied wild forms.
(8/29. Mr. A. Strickland in 'Annals and Mag. of Nat. Hist.' 3rd series
volume 3 1859 page 122.) At our Shows two breeds are exhibited; viz., the
Embden and Toulouse; but they differ in nothing except colour. (8/30.
'Poultry Chronicle' volume 1 1854 page 498; volume 3 page 210.) Recently a
smaller and singular variety has been imported from Sebastopol (8/31. 'The
Cottage Gardener' September 4, 1860 page 348.), with the scapular feathers
(as I hear from Mr. Tegetmeier, who sent me specimens) greatly elongated,
curled, and even spirally twisted. The margins of these feathers are
rendered plumose by the divergence of the barbs and barbules, so that they
resemble in some degree those on the back of the black Australian swan.
These feathers are likewise remarkable from the central shaft, which is
excessively thin and transparent, being split into fine filaments, which,
after running for a space free, sometimes coalesce again. It is a curious
fact that these filaments are regularly clothed on each side with fine down
or barbules, precisely like those on the proper barbs of the feather. This
structure of the feathers is transmitted to half-bred birds. In Gallus
sonneratii the barbs and barbules blend together, and form thin horny
plates of the same nature with the shaft: in this variety of the goose, the
shaft divides into filaments which acquire barbules, and thus resemble true
barbs.

Although the domestic goose certainly differs somewhat from any known wild
species, yet the amount of variation which it has undergone, as compared
with that of most domesticated animals, is singularly small. This fact can
be partially accounted for by selection not having come largely into play.
Birds of all kinds which present many distinct races are valued as pets or
ornaments; no one makes a pet of the goose; the name, indeed, in more
languages than one, is a term of reproach. The goose is valued for its size
and flavour, for the whiteness of its feathers which adds to their value,
and for its prolificness and tameness. In all these points the goose
differs from the wild parent-form; and these are the points which have been
selected. Even in ancient times the Roman gourmands valued the liver of the
WHITE goose; and Pierre Belon (8/32. 'L'Hist. de la Nature des Oiseaux' par
P. Belon 1555 page 156. With respect to the livers of white geese being
preferred by the Romans see Isid. Geoffroy St.-Hilaire 'Hist. Nat. Gen.'
tome 3 page 58.) in 1555 speaks of two varieties, one of which was larger,
more fecund, and of a better colour than the other; and he expressly states
that good managers attended to the colour of their goslings, so that they
might know which to preserve and select for breeding.

THE PEACOCK.

This is another bird which has hardly varied under domestication, except in
sometimes being white or piebald. Mr. Waterhouse carefully compared, as he
informs me, skins of the wild Indian and domestic bird, and they were
identical in every respect, except that the plumage of the latter was
perhaps rather thicker. Whether our birds are descended from those
introduced into Europe in the time of Alexander, or have been subsequently
imported, is doubtful. They do not breed very freely with us, and are
seldom kept in large numbers,--circumstances which would greatly interfere
with the gradual selection and formation of new breeds.

There is one strange fact with respect to the peacock, namely, the
occasional appearance in England of the "japanned" or "black-shouldered"
kind. This form has lately been named on the high authority of Mr. Sclater
as a distinct species, viz. Pavo nigripennis, which he believes will
hereafter be found wild in some country, but not in India, where it is
certainly unknown. The males of these japanned birds differ conspicuously
from the common peacock in the colour of their secondary wing-feathers,
scapulars, wing-coverts, and thighs, and are I think more beautiful; they
are rather smaller than the common sort, and are always beaten by them in
their battles, as I hear from the Hon. A.S.G. Canning. The females are much
paler coloured than those of the common kind. Both sexes, as Mr. Canning
informs me, are white when they leave the egg, and they differ from the
young of the white variety only in having a peculiar pinkish tinge on their
wings. These japanned birds, though appearing suddenly in flocks of the
common kind, propagate their kind quite truly. Although they do not
resemble the hybrids which have been raised between P. cristatus and
muticus, nevertheless they are in some respects intermediate in character
between these two species; and this fact favours, as Mr. Sclater believes,
the view that they form a distinct and natural species. (8/33. Mr. Sclater
on the black-shouldered peacock of Latham 'Proc. Zoolog. Soc.' April 24,
1860. Mr. Swinhoe at one time believed, 'Ibis' July 1868, that this kind of
peafowl was found wild in Cochin China, but he has since informed me that
he feels very doubtful on this head.)

On the other hand, Sir H. Heron states (8/34. 'Proc. Zoolog. Soc.' April
14, 1835.) that this breed suddenly appeared within his memory in Lord
Brownlow's large stock of pied, white, and common peacocks. The same thing
occurred in Sir J. Trevelyan's flock composed entirely of the common kind,
and in Mr. Thornton's stock of common and pied peacocks. It is remarkable
that in these two latter instances the black-shouldered kind, though a
smaller and weaker bird, increased, "to the extinction of the previously
existing breed." I have also received through Mr. Sclater a statement from
Mr. Hudson Gurney that he reared many years ago a pair of black-shouldered
peacocks from the common kind; and another ornithologist, Prof. A. Newton,
states that, five or six years ago, a female bird, in all respects similar
to the female of the black-shouldered kind, was produced from a stock of
common peacocks in his possession, which during more than twenty years had
not been crossed with birds of any other strain. Mr. Jenner Weir informs me
that a peacock at Blackheath whilst young was white, but as it became older
gradually assumed the characters of the black-shouldered variety; both its
parents were common peacocks. Lastly, Mr. Canning has given a case of a
female of this same variety appearing in Ireland in a flock of the ordinary
kind. (8/35. 'The Field' May 6, 1871. I am much indebted to Mr. Canning for
information with respect to his birds.) Here, then, we have seven well
authenticated cases in Great Britain of japanned birds, having suddenly
appeared within recent times in flocks of the common peafowl. This variety
must also have formerly appeared in Europe, for Mr. Canning has seen an old
picture, and another is referred to in the 'Field,' with this variety
represented. These facts seem to me to indicate that the japanned peacock
is a strongly marked variety or "sport," which tends at all times and in
many places to reappear. This view is supported by the young being at first
white like the young of the white breed, which is undoubtedly a variation.
If, on the other hand, we believe the japanned peacock to be a distinct
species, we must suppose that in all the above cases the common breed had
at some former period been crossed by it, but had lost every trace of the
cross; yet that the offspring of these birds suddenly and completely
reacquired through reversion the characters of P. nigripennis. I have heard
of no other such case in the animal or vegetable kingdom. To perceive the
full improbability of such an occurrence, we may suppose that a breed of
dogs had been crossed at some former period with a wolf, but had lost every
trace of the wolf-like character, yet that the breed gave birth in seven
instances in the same country, within no great length of time, to a wolf
perfect in every character; and we must further suppose that in two of the
cases, the newly produced wolves afterwards spontaneously increased to such
an extent as to lead to the extinction of the parent breed of dogs. So
remarkable a bird as the P. nigripennis, when first imported, would have
realised a large price; it is therefore improbable that it should have been
silently introduced and its history subsequently lost. On the whole the
evidence seems to me, as it did to Sir R. Heron, to be decisive in favour
of the japanned or black-shouldered breed being a variation, induced by
some unknown cause. On this view, the case is the most remarkable one ever
recorded of the abrupt appearance of a new form, which so closely resembles
a true species that it has deceived one of the most experienced of living
ornithologists.

THE TURKEY.

It seems fairly well established by Mr. Gould (8/36. 'Proc. Zoolog. Soc.'
April 8, 1856 page 61. Prof. Baird believes (as quoted in Tegetmeier
'Poultry Book' 1866 page 269) that our turkeys are descended from a West
Indian species now extinct. But besides the improbability of a bird having
long ago become extinct in these large and luxuriant islands, it appears
(as we shall presently see) that the turkey degenerates in India, and this
fact indicates that it was not aboriginally an inhabitant of the lowlands
of the tropics.), that the turkey, in accordance with the history of its
first introduction, is descended from a wild Mexican form, which had been
domesticated by the natives before the discovery of America, and which is
now generally ranked as a local race, and not as a distinct species.
However this may be, the case deserves notice because in the United States
wild male turkeys sometimes court the domestic hens, which are descended
from the Mexican form, "and are generally received by them with great
pleasure." (8/37. Audubon 'Ornithological Biography' volume 1 1831 pages 4-
13; and 'Naturalist's Library' volume 14 'Birds' page 138.) Several
accounts have likewise been published of young birds, reared in the United
States from the eggs of the wild species, crossing and commingling with the
common breed. In England, also, this same species has been kept in several
parks; from two of which the Rev. W.D. Fox procured birds, and they crossed
freely with the common domestic kind, and during many years afterwards, as
he informs me, the turkeys in his neighbourhood clearly showed traces of
their crossed parentage. We here have an instance of a domestic race being
modified by a cross with a distinct wild race or species. F. Michaux (8/38.
F. Michaux 'Travels in N. America' 1802 English translation page 217.)
suspected in 1802 that the common domestic turkey was not descended from
the United States species alone, but likewise from a southern form, and he
went so far as to believe that English and French turkeys differed from
having different proportions of the blood of the two parent-forms.

English turkeys are smaller than either wild form. They have not varied in
any great degree; but there are some breeds which can be distinguished as
Norfolks, Suffolks, Whites, and Copper-coloured (or Cambridge), all of
which, if precluded from crossing with other breeds propagate their kind
truly. Of these kinds, the most distinct is the small, hardy, dull-black
Norfolk turkey, of which the chickens are black, occasionally with white
patches about the head. The other breeds scarcely differ except in colour,
and their chickens are generally mottled all over with brownish-grey.
(8/39. 'Ornamental Poetry' by the Rev. E.S. Dixon 1848 page 34.) The
inferior tail-coverts vary in number, and according to a German
superstition the hen lays as many eggs as the cock has feathers of this
kind. (8/40. Bechstein 'Naturgesch. Deutschlands' b. 3 1793 s. 309.) Albin
in 1738, and Temminck within a much later period, describe a beautiful
breed, dusky-yellowish, brown above and white beneath, with a large top-
knot of soft plumose feather. The spurs of the male were rudimentary. This
breed has been for a long time extinct in Europe; but a living specimen has
lately been imported from the east coast of Africa, which still retains the
top-knot and the same general colouring and rudimentary spurs. (8/41. Mr.
Bartlett in 'Land and Water' October 31, 1868 page 233; and Mr. Tegetmeier
in the 'Field' July 17, 1869 page 46.) Mr. Wilmot has described (8/42.
'Gardener's Chronicle' 1852 page 699.) a white turkey-cock having a crest
formed of "feathers about four inches long, with bare quills, and a tuft of
soft white down growing at the end." Many of the young birds inherited this
kind of crest, but afterwards it fell off or was pecked out by the other
birds. This is an interesting case, as with care a new breed might probably
have been formed; and a top-knot of this nature would have been to a
certain extent analogous to that borne by the males in several allied
genera, such as Euplocomus, Lophophorus, and Pavo.

Wild turkeys, believed in every instance to have been imported from the
United States, have been kept in the parks of Lords Powis, Leicester, Hill,
and Derby. The Rev. W.D. Fox procured birds from the two first-named parks,
and he informs me that they certainly differed a little from each other in
the shape of their bodies and in the barred plumage on their wings. These
birds likewise differed from Lord Hill's stock. Some of the latter kept at
Oulton by Sir P. Egerton, though precluded from crossing with common
turkeys, occasionally produced much paler-coloured birds, and one that was
almost white, but not an albino. These half-wild turkeys, in thus differing
slightly from each other, present an analogous case with the wild cattle
kept in the several British parks. We must suppose that such differences
have resulted from the prevention of free intercrossing between birds
ranging over a wide area, and from the changed conditions to which they
have been exposed in England. In India the climate has apparently wrought a
still greater change in the turkey, for it is described by Mr. Blyth (8/43.
E. Blyth 'Annals and Mag. of Nat. Hist.' 1847 volume 20 page 391.) as being
much degenerated in size, "utterly incapable of rising on the wing," of a
black colour, and "with the long pendulous appendages over the beak
enormously developed."

THE GUINEA FOWL.

The domesticated Guinea fowl is now believed by some naturalists to be
descended from the Numida ptilorhynca, which inhabits very hot, and, in
parts, extremely arid districts in Eastern Africa; consequently it has been
exposed in this country to extremely different conditions of life.
Nevertheless it has hardly varied at all, except in the plumage being
either paler or darker-coloured. It is a singular fact that this bird
varies more in colour in the West Indies and on the Spanish Main, under a
hot though humid climate, than in Europe. (8/44. Roulin makes this remark
in 'Mem. de divers Savans, 1'Acad. des Sciences' tome 6 1835 page 349. Mr.
Hill of Spanish Town in a letter to me describes five varieties of the
Guinea fowl in Jamaica. I have seen singular pale-coloured varieties
imported from Barbadoes and Demerara.) The Guinea fowl has become
thoroughly feral in Jamaica and in St. Domingo (8/45. For St. Domingo see
M. A. Salle, in 'Proc. Zoolog. Soc.' 1857 page 236. Mr. Hill remarks to me,
in his letter, on the colour of the legs of the feral birds in Jamaica.),
and has diminished in size; the legs are black, whereas the legs of the
aboriginal African bird are said to be grey. This small change is worth
notice on account of the often-repeated statement that all feral animals
invariably revert in every character to their original type.

THE CANARY BIRD.

As this bird has been recently domesticated, namely, within the last 350
years, its variability deserves notice. It has been crossed with nine or
ten other species of Fringillidae, and some of the hybrids are almost
completely fertile; but we have no evidence that any distinct breed has
originated from such crosses. Notwithstanding the modern domestication of
the canary, many varieties have been produced; even before the year 1718 a
list of twenty-seven varieties was published in France (8/46. Mr. B.P.
Brent 'The Canary, British Finches' etc. pages 21, 30.), and in 1779 a long
schedule of the desired qualities was printed by the London Canary Society,
so that methodical selection has been practised during a considerable
period. The greater number of the varieties differ only in colour and in
the markings of their plumage. Some breeds however, differ in shape, such
as the hooped or bowed canaries, and the Belgian canaries with their much
elongated bodies. Mr. Brent (8/47. 'Cottage Gardener' December 11, 1855
page 184: an account is here given of all the varieties. For many
measurements of the wild birds, see Mr. E. Vernon Harcourt ibid December
25, 1855 page 223.) measured one of the latter and found it eight inches in
length, whilst the wild canary is only five and a quarter inches long.
There are top-knotted canaries, and it is a singular fact that, if two top-
knotted birds are matched, the young, instead of having very fine top-
knots, are generally bald, or even have a wound on their heads. (8/48.
Bechstein 'Naturgesch. der Stubenvogel' 1840 s. 243; see s. 252 on the
inherited song of Canary-birds. With respect to their baldness see also W.
Kidd 'Treatise on Song-Birds.') It would appear as if the top-knot were due
to some morbid condition, which is increased to an injurious degree when
two birds in this state are paired. There is a feather-footed breed, and
another with a kind of frill running down the breast. One other character
deserves notice from being confined to one period of life, and from being
strictly inherited at the same period; namely, the wing and tail feathers
in prize canaries being black, "but this colour is retained only until the
first moult; once moulted, the peculiarity ceases." (8/49. W. Kidd
'Treatise on Song-Birds' page 18.) Canaries differ much in disposition and
character, and in some small degree in song. They produce eggs three or
four times during the year.

GOLD-FISH.

Besides mammals and birds, only a few animals belonging to the other great


 


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