BIRDS. 207 
DIVISION OF THE CLASS OF BIRDS INTO ORDERS. 
Or all classes of animals, that of Birds is the most strongly characterized, 
that in which the species have the greatest mutual resemblance, and 
which is separated from all others by the greatest interval; circumstances 
which, at the same time, render its subdivision the more difficult. 
Their distribution is founded, like that of the Mammalia, on the organs 
of manducation or the bill, and on those of prehension, that is, still on 
the bill, and more particularly on the feet. 
The first that arrest our attention are the palmated feet, or those in 
which the toes are connected by membranes-~such distinguish all Swim- 
ming Birds. The position of these feet behind; the length of the ster- 
num; the neck, often longer than the legs, to enable it to reach below; 
the dense, polished plumage, impermeable to water, all concur with the 
feet in making good navigators of the Palmipedes. 
In other birds, which most commonly are partially web-footed, at least 
between the external toes, we observe elevated tarsi; legs divested of 
feathers at their lower extremities; a long, thin shape, and in fine, all the 
requisites for wading along the shores of rivers to seek their food. Such, 
in fact, is the regimen of the greater number; and although some of them 
inhabit dry grounds, they are called Shore-Birds, or Waders. 
Among the true land birds, the Gallinacee, like our domestic Cock, 
have a heavy carriage, a limited power of flying, a moderate bill, the 
upper mandible of which is arched; the nostrils partly covered by a soft 
and inflated scale; the toes almost always indented on the edges, and 
short membranes between the bases of the anterior ones. They fly hea- 
vily, and but a short distance at a time. Their chief food is grain, 
Birds of prey have a hooked bill, the point of which is sharp, and 
curved downwards; the nostrils pierced in a membrane which invests the 
whole base of that bill, and feet armed with vigorous talons. They live 
on flesh, pursue other birds, and are consequently, for the most part, 
vigorous in flight. The greater number have still a slight web between 
the external toes. 
The Passerine comprise many more species than all the other families; 
but their organization presents so many analogies that they cannot be 
separated, although varying greatly in size and strength. Their two ex- 
ternal toes are united at the base, and sometimes for a part of their 
length. 
Finally, the name of Scansorie, or Climbers, has been given to those 
birds whose external toe, like the thumb, is directed backwards, because 
