42 
NATURAL HISTORY. 
[east. ZOOL. 
marginal membrane; their bills are short and much elevated at the 
base; these are principally inhabitants of the ocean or saline lakes, but 
a few are found on lakes and rivers of the interior of the country; they 
obtain their food principally by diving, which consists of small crabs, 
shell fish, and aquatic plants. The JErismaturince (Case 150) have a 
lengthened and cuneiform tail, composed of numerous narrow pointed 
feathers; their hind toe is moderately webbed; they are seen on the 
fresh water or saline lakes and interior seas of northern and eastern 
Europe, &c.; their food consists of vegetable matter, for which they 
often dive. The Mergansers ( Mergince , Case 151) have narrow cy¬ 
lindrical bills, with the margin serrated and the tip armed with a 
hooked nail; they are found in the Arctic regions ; their food consists 
principally of fish, which they take by rapid diving, also small crabs and 
insects. 
The family of the Divers (Colymbidje, Cases 152 and 153) have 
very moderately feathered short wings, and the legs placed so far back 
on the body, that they always assume an erect position. The bill is 
compressed at the tip, and pointed. Some suspend their nests on 
rushes at the surface of the water. The Divers ( Colymbince , Case 152) 
have the feet large, with the outer toe longer than the middle one, 
and all the front ones entirely webbed, with the hind toe connected 
to the outer membrane of the inner one, and lobed. They are 
found in the northern regions, visiting the lakes of the interior during 
their breeding season. They are rapid divers, feeding on fish, and 
sometimes vegetables. The Grebes ( Podicipince , Case 153) have the 
toes flattened, separate, and broadly fringed on the sides by a mem¬ 
brane, and their outer longer than the middle one ; their bill is lengthened 
and pointed; found in most parts of the world, on the lakes, rivers, and 
fens of the interior; others seek the ocean, especially during the winter. 
Their food consists of small fish, crabs, insects, and fry of fish, and are 
said to carrry their young under their wings when alarmed. t 
The family of Auks (Alcidze, Cases 154 and 155) have, like the 
Divers, very short wings, and the legs placed far behind the centre of 
the body, which enables them to stand nearly erect, but they have the 
toes all united by a web. They are oceanic birds. In some the wings are 
covered with feathers, and they me stly have no hind toe. Some of these 
birds deposit their eggs in a sort of burrow, which they dig like rabbits. 
The Auks ( Alcince , Case 154) have a compressed and keeled bill, with 
the tip acute and hooked ; their wings very short but perfectly formed. 
The hind toe is wanting. They are found in the Northern Ocean, and 
appear in the more temperate climates during the winter; feed on fish 
and small crabs. The Sea Parrots ( Phaleridince , Case 15) have the bill 
as long or shorter than the head, depressed at the base, with the culmen 
arched and emarginated at the tip ; the base of some is covered by an 
osseous membrane ; their wings are short and pointed ; the hind toe is 
wanting. They live generally in flocks far from land, in the Arctic 
regions; their food consists of crabs, shell-fish, and other small marine 
animals. The Guillemots ( Urince , Case 155) have the bill straight, 
compressed, convex, with the tip curved and notched; their wings short; 
the hind toe is wanting. They inhabit the Arctic Sea, and swim and dive 
in pursuit of their finny prey, exercising their wings in the water as 
much as their feet. The Penguins ( Spheniscince , Case 154) have the 
