80 
VERTEBRATA. 
THE EUROPEAN GOAT-SUCKKK. 
The first group of the Passerine birds, that of the Mssirostres, is characterized by having the 
gape-line continued far back, usually reaching under the eyes. They are generally insectivorous 
birds, and many of them take their prey on the wing ; the gape is accordingly usually furnished 
with bristles, which, by enlarging the space occupied by the mouth, greatly facilitate the capture 
of insects. This group includes the Goat-Suckers, Swallows, Motmots, Todies, Eurylaimince, 
Rollers, Trogons, Puff-hirds, Kingfishers, Jacamars, and Bee-Eaters. 
THE CAPRIMULGID^ OR GOAT-SUCKERS. 
The birds of this curious family, often called JSfight-Swalloivs, have some resemblance to the 
owls in their large heads, large eyes, and mottled cover- 
ing, and also in their nocturnal or crepuscular habits 
and their noiseless flight. Their bill is short and weak ; 
the tarsi are short, and frequently covered with plumes; 
tbe feet are small and weak, and hence these birds, in- 
stead of sitting across the perch and grasping it with 
their feet, sit lengthwise upon it. The middle toe is 
very long, and the claw is pectinated, or toothed like a 
comb. The nse of this has been a matter of dispute : 
some say that it serves to hold fast beetles and other 
slippery insects, and others that it is employed to 
comb the birds' whiskers. They live upon moths, bee- 
tles, and other insects, which they generally pursue 
during the twilight, sometimes well into the night, their 
large visual organs collecting sufficient light for them to 
perceive their minute prey long after it is invisible to 
the eye of man. The enormous gape of their mouths, 
aided by bristles springing from each side of the upper 
mandible, furnishes a capacious trap for securing their 
game. The form and extent of the mouth are so extraor- 
dinary, that ages ago the people of Greece and Italy, 
