150 ELEMENTS OF ORNITHOLOGY. 
Tuer Bopy AnD TAIL. 
The Body of a bird forms, roughly speaking, an egg-shaped 
mass. This may be somewhat laterally pressed in, or it may be 
flattened from above downwards, these conditions being termed 
(as in the analogous conditions of the bill) compressed or 
depressed respectively. As in ourselves and in beasts, the body 
has its dorsal and its ventral region. The former is sometimes 
called the notewum and the latter the gastreum. The feathers 
of the belly are generally softer than those of the back. The 
surface of the back taken together with the dorsal, or upper, 
surface of the wings is also sometimes spoken of as the mantle. 
The feathers which grow on the shoulders are named scapulars 
or scapularies, and, of course, the space between them is the 
anterscapular region. The part immediately behind this is 
sometimes distinguished as the lower back or tergum, and behind 
this comes the rump or wropygium. 
The ventral region would seem hardly to need description, 
such simple terms as pectoral, abdominal, and lateral apparently 
explaining themselves. Yet confusion has arisen, so that it is 
necessary to point out that the breast, or pectoral region, is the 
part over the sternum, behind which is the abdomen, and in 
front of which is the prepectus. The term “ crissum” is one 
which is variously, and therefore rather misleadingly, applied to 
a region it may be desired to distinguish, and which is in near 
proximity to the vent. It is best applied to feathers just behind 
the vent, that is to the more anteriorly situated of those feathers 
which we shall soon describe—amongst those of the tail—as 
“ under tail-coverts.” 
Tail.—The tail of a bird, in the ordinary acceptation of the 
term, means the collection of more or less strong, more or less 
elongated feathers which are implanted into the skin of the 
hinder end of “the body. But evidently this “tail” has no re- 
lation to what we mean by a “ tail,” when we speak of the tail 
of a beast. Moreover, as we shall soon see, elongated con- 
spicuous feathers, commonly called the tail of certain birds, do 
not correspond with the tail-feathers which other birds possess. 
The tail of a beast, for example of a Cat, consists of a firm 
bony basis surrounded with flesh and sinew and invested by the 
skin. Such a tail always exists in birds, but it is a very 
different structure from what is ordinarily called “a bird’s tail.” 
Most aquatic beasts, and other backboned animals which 
