192 ON THE CLASSIFICAT: 
alihiocg much more common on_ at 
The second (Uria) includes the guill sida 
guished from the last by the’ absence of the hi ind 
toe; and these again are confined to the Northe 
Ocean, The third and fourth are Podiceps and F od 
both of which agree in having the membrane be 
the toes divided into lobes, similar to those on the 
of the coot ; but in the first the hinder toe is lobatec d, 
while in the latter it is simple. The grebes are the 
most imperfect flyers, since the divers have their 
wings not much shorter than several of the ducks, 
(214.) The Axcipa form the third principal fa. 
mily, and include the penguins, the puffins, and all 
those singularly constructed groups where the wing 
are abortive, or, in other words, assume more 
appearance, as they perform the office, of fins: | 
feet, moreover, are so little adapted for walking, that 
even the obsolete toe, seen in the ducks and divers, is 
here generally wanting. We thus see the power of 
swimming developed in the most perfect manner in 
birds which, in every other faculty, are the most imper= 
fect in creation. The natural series of the genera, h 
some, have been commenced with Uria; by others 
with some of the Alce, or puffins. The little 
(Mergulus) has been detached on account of its a 
thick, and convex bill, the base of which is covere 
with the frontal feathers: there is but one species, a 
polar bird, yet sometimes seen on the British coasts: 
this form may probably be represented in the southern 
hemisphere by the crested auks (Phaleris Tem.)—the 
species of which are but obscurely understood: the 
arctic puffin, and two other northern species, form the’ 
restricted genus Mormon. The great auk and the 
razorbill are now almost the only species left in the 
original genus Alca of Jinneus: the first is nearly the 
size of a goose, and is occasionally found in the aretie 
seas: this singular and very rare bird is totally without 
the power of flight; and the latter species can only — 
raise itself on wing just above the surface of the sea, 
