226 The Bird 
Triceratops, an interesting transitional condition is found. 
The front of the mouth was beak-like and horny, while 
farther back were the masticatory teeth. 
Starting with the generalized beak of the Arche- 
opteryx, which, we remember, was furnished with teeth, 
we are almost at a loss in which direction to turn, 
so many and so varied are the beaks of modern birds. 
No trace of teeth, however, is to be found in the adults 
of any of them. The bill of a crow or raven and, to a 
lesser extent, that of his near relatives, the jay and the 
blackbird, is perhaps in shape most like that of the ‘bird 
of old,’ and is suited to the many purposes which the 
varied life of these intelligent birds requires. 
The crow or the raven is an excellent example of a 
modern bird with a remarkably generalized diet, in striking 
contrast to those birds whose bills show them to be fitted 
for feeding only on some strictly defined food. With 
his strong, ample beak the crow can dig up recently 
planted corn, or crack the hard shells of acorns; he en- 
joys stealing the eggs and the young birds of thrushes, 
orioles, sparrows, warblers, and quail, and I have seen 
a crow chase, capture, and carry off a half-dozen wild Mal- 
lard ducklings in one morning! These birds are, in ad- 
dition, able to capture insects of all kinds, besides pick- 
ing berries, and ducking their heads under water in quest 
of the shrimps which live in tide-pools. In short, their 
bill serves them well in procuring many kinds of food, 
from earth, water, or tree; as well as in carrying great 
quantities of sticks, which they use in the construction 
of their nests. These birds are so skilful with their 
