sometimes very long. He
mentions also another breed similarly characterized, in which the hens are
excellent layers, but are apt to disturb and break their eggs owing to
their spurs.

Mr. Layard[417] 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 finds that the same rule holds 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. {257} But formerly in Germany
the skull of the hen alone was protuberant: Blumenbach,[418] who
particularly attended to abnormal peculiarities in domestic animals,
states, in 1813, that this was the case; and Bechstein had previously, in
1793, observed the same fact. This latter author has carefully described
the effects of a crest on the skull not only in fowls, but in 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, and he attended 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 states
that he never observed this protuberance in male fowls. Hence there can be
no doubt that this remarkable 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