NATATORES. COLYMBUS. 405 
in length. Front toes entirely webbed, hind toe furnished 
with a lobe, and partly connected with the exterior membrane 
of the inner toe. Nails flat and broad. 
General contour broad and flat. Plumage thick, close, ad- 
pressed, and glossy. 
In their aquatic habits and mode of life, the Divers strongly 
resemble the preceding genus, being the constant inhabitants 
of the watery element, to which, indeed, we may consider 
them as equally confined by the similar conformation and 
position of their legs. They differ, however, from the Grebes 
in having the toes connected throughout their length, as in 
the Alcade and Anatide; but their form and articulation 
are like those of Grebes, and the tarsus is of the same com- 
pressed shape. In this genus the hind toe, in addition to its 
lobe, is connected towards its base with the membrane skirt- 
ing the exterior edge of the inner toe, shewing in this re- 
spect an apparent approach to the Pelicanide. They pos- 
sess a true tail, but it is very short, and concealed by the 
upper coverts, which are as long as the rectrices. Their 
wings are short and sharp pointed ; and though they rarely 
fly, yet they can do so occasionally, both with swiftness and 
for a considerable time. In swimming, their broad and 
flattened body is immersed in the water, the head and neck 
only appearing above the surface. They dive continually, 
and with littie apparent exertion; their progress beneath is 
very rapid, and they can stretch to a great distance without 
rising to breathe. They live upon fish, aquatic insects, and 
sometimes vegetables, but the first form the principal part of 
their support. During their Polar migration they retire to 
the fresh water lakes of the interior, where they breed close 
to the brink of the water, upon islets, or other suitable sta- 
tions; but on the approach of winter repair again to the 
ocean. They lay but two eggs, and the young differ greatly 
from the adults in plumage, not acquiring maturity until 
after the third general moult. They are birds of a wild dis- 
