EXTERNAL ANATOMY. BRISTLES. 55 
Other race. A similar structure is also apparent in some 
of the typical chatterers, as the genus Casmorhynchus ; 
but it is intended for a very different purpose. The 
wide mouth of the swallow tribe is not for the passage 
of large insects — because it is well known that these 
birds feed only upon such as are very small — but to 
give them a greater chance of securing their prey. The 
chatterers, on the contrary, feed after the manner of 
ordinary birds, that is, with closed wings ; but a very 
wide mouth is essential to them, for they frequently 
swallow, in a whole state, wild fruits bigger than our 
sloes ; and in dissecting these birds, we have often been 
astonished at the size of the fruit discovered, in an 
entire state, in their crops. There must be something 
very peculiar in the economy of those little-known birds, 
the Eurylarninm, or broadbiUs of India, whose mouths 
far exceed in width those of the most typical flycatchers 
{Musvicapince). Their prey is probably of a larger 
description tlian that captured by their congeners ; or, 
as one species is known to feed both upon insects and 
vegetables, it is probable that the others also partake of 
berries not much inferior in size to those devoured 
by the chatterers of llrazil. It would appear, at first, 
preposterous to say that lips are to be found among 
birds ; and yet there are instances where parts, at least 
analogous thereto, might be so termed. In the Ceb~ 
lepyris labiata, — a very rare species, of the size of our 
blackbird, found in Southern Africa, — the basal half of 
each mandible is margined by a skin, which is destitute 
of feathers, and of a bright red colour ; and the same 
development of the part is observable in most young 
birds, or nestlings, before they have acquired their first 
featheis. 
(S.'j.) The mouth is often defended by rictal bristles, 
more or less stiff, which are from five to six in number, 
and are situated at the base of the upper mandible, 
immediately above the angle of the mouth. Sometimes, 
as in the genus Pogonias {Jig- 23.) composed of the 
Barbut woodpeckers of Africa, these bristles extend 
E 4 
