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.