nstead of a very long beak, has a very short and very broad
one. The pouter has a much elongated body, wings, and legs; and its
enormously developed crop, which it glories in inflating, may well
excite astonishment and even laughter. The turbit has a very short and
conical beak, with a line of reversed feathers down the breast; and it
has the habit of continually expanding slightly the upper part of the
oesophagus. The Jacobin has the feathers so much reversed along the back
of the neck that they form a hood, and it has, proportionally to its
size, much elongated wing and tail feathers. The trumpeter and laugher,
as their names express, utter a very different coo from the other
breeds. The fantail has thirty or even forty tail-feathers, instead of
twelve or fourteen, the normal number in all members of the great pigeon
family; and these feathers are kept expanded, and are carried so erect
that in good birds the head and tail touch; the oil-gland is quite
aborted. Several other less distinct breeds might have been specified.

In the skeletons of the several breeds, the development of the bones
of the face in length and breadth and curvature differs enormously. The
shape, as well as the breadth and length of the ramus of the lower
jaw, varies in a highly remarkable manner. The number of the caudal and
sacral vertebrae vary; as does the number of the ribs, together with
their relative breadth and the presence of processes. The size and shape
of the apertures in the sternum are highly variable; so is the degree
of divergence and relative size of the two arms of the furcula. The
proportional width of the gape of mouth, the proportional length of the
eyelids, of the orifice of the nostrils, of the tongue (not always in
strict correlation with the length of beak), the size of the crop and
of the upper part of the oesophagus; the development and abortion of
the oil-gland; the number of the primary wing and caudal feathers; the
relative length of wing and tail to each other and to the body; the
relative length of leg and of the feet; the number of scutellae on
the toes, the development of skin between the toes, are all points of
structure which are variable. The period at which the perfect plumage is
acquired varies, as does the state of the down with which the nestling
birds are clothed when hatched. The shape and size of the eggs vary. The
manner of flight differs remarkably; as does in some breeds the voice
and disposition. La