THE BONES. 
45 
and Cassowary, where they are so small and insig- 
nificant as merely to assist in balancing their bodies 
when they run, the keel of the breast- hone is entirely 
wanting, or the furcula or merry-thought very im- 
perfectly developed. On the other hand, in the Eagle 
and Hawk tribe, they are proportionally strong, 
conspicuous, and well defined. 
The hones of the wings next come under obser- 
vation: and these, as may he expected, in birds of 
prey, and some others, which have to carry their 
food frequently to a considerable distance, or live 
much in the air, are of great length; whereas, in 
domestic fowls, they are very small in proportion to 
the size of their bodies ; and in the Penguins, which, 
as has been observed, live almost entirely on the 
water, and, in diving, may be said to fly beneath its 
surface, they are remarkable for their flattened ap- 
pearance, as if they had been pressed ; approaching 
more to the form of a fin than a wing, much resem- 
bling the flappers of a turtle. 
The last bones which remain for consideration, are 
those composing the legs and feet, which are the 
more worthy of attention, inasmuch as to a certain 
degree, upon these, and of the feet more especially, 
depends the division or classification of birds. 
It is not, however, our intention to enter into an 
explanation of what is called the anatomical struc- 
ture of these limbs, further than to point out 
wherein they resemble or differ from our own, 
and correct a very common mistake into which 
inexperienced observers are apt to fall. We sub- 
join two figures, No. 1, representing the leg of a 
man ; No, 2, that of a birfl ; in which the corre- 
