284 NATATOHES. 



secutively to them even in a natural arrangement ; but they 

 differ in so many particulars, that they cannot with propriety 

 be included in the same genus. 



Their general characters as a genus are the bill of mode- 

 rate length, straight, compressed in its whole length, and very 

 sharp pointed ; the nostrils, at the base, oval, and half closed 

 by a membranous valve ; the legs articulated far backward, 

 with the tarsi compressed ; the three front toes very long, 

 and connected for their whole length by a membranous web, 

 and the hind toe very short, with the web loose and merely 

 rudimental ; the wings are short in proportion to the size of 

 the bird ; and the tail is very short and rounded. The entire 

 webs of the feet, and the possession of a tail, are the most 

 obvious external characters, in which they differ from the 

 grebes. 



As is the case with the grebes, the water is the proper and 

 peculiar province of the divers, on the surface of which, or 

 immersed in its volume, they have as much command of 

 themselves as any land birds have in the air. The water is 

 to them much the same as the air is to the swifts, and even 

 more so, for the divers repose on the water, which the swifts 

 cannot do in the air. They do not come to the land, except 

 in the breeding time, and even then they come as little land- 

 ward as possible. Small islets, jutting points, and headlands, 

 (places which have more sea than land in their horizon,) are 

 those upon which they breed. They are exposed to few 

 enemies or casualties, and therefore their broods are not 

 numerous : their eggs are not more than two, rather large 

 for the size of the birds, as the young are so far grown when 

 they come out of the shell, that they are almost instantly 

 able to take the water. 



These birds are, indeed, much more independent of con- 

 tingencies than any of those that make the air their chief 

 element ; and generally, than their brethren of the waters. 



