390 NATATORES. PODICEPS. 
this family are unable to walk upon land, and they rarely of 
their own accord come to shore, unless for the purpose of 
reproduction ; and this is almost always effected on the im- 
mediate margin of the water, or amidst the floating herbage 
that covers many of the situations they inhabit. They swim 
and dive with equal ease, and can remain for a long time 
submerged. ‘The genera at present assigned to this family 
are two, viz. the Grebe (Podiceps), and Diver (Colymbus). 
Genus PODICEPS, Laryau. GREBE. 
GENERIC CHARACTERS. 
Buixt as long as, or longer than, the head, strong, slightly 
compressed, strait, entire, hard, and pointed; the upper 
mandible inclining slightly towards the tip; the lower one 
turning upwards from the gonys, or angle; tomia of both 
mandibles bending inwards. Nostrils lateral, basal, linear, 
pierced in the middle of the nasal fosse. Lorum, or space 
between the corner of the bill and the eye, naked. 
Wings short, and concave. No tail. 
Legs placed at the posterior extremity of the body; the 
tibize enclosed within the integuments of the abdomen. Tarsi 
much compressed; feet of four toes, three before, and one 
behind; the front toes much flattened, and each furnished 
with a broad membrane; which membranes become united 
near the base; outer toe longer than the middle one; hind 
toe articulated on the tarsus, and provided with a lobated 
membrane. Nails large, flat, and broad. Plumage soft, 
downy, thick; with a silky lustre. 
In former systems, when the natural affinities which con- 
nect the various Orders, Families, &c. together were neglect- 
ed, or at least but imperfectly vestigated, the Grebes, from 
a fancied resemblance (for such it may properly be termed) 
