185 



COLYMBIDJE, OR DIVERS. 



SUCCEEDING the extensive and generally distributed 

 family of the Ducks and Goosanders, we place 

 another, much more limited in numbers, but of 

 habits even more peculiarly aquatic. They are 

 all most expert divers, as their title indicates, live 

 entirely on the water, except during the process of 

 incubation, and undergo a periodical change of plu- 

 mage in one form or another. The different modi- 

 fications of form, though limited, are distributed 

 over the world, but are scarcely employed in any 

 economical purpose. The skins of the larger species 

 are sometimes dressed and used as ornaments. We 

 have only two genera entering the British list, the 

 first, the True Divers^ have the body flat and heavy, 

 and when stretched out, tapering and dart-like ; 

 the wings small, sharp-pointed, and stiff, admirably 

 adapted for progress under water, at the same time 

 capable of quickly transporting their owners over 

 land when required. The legs are placed still more 

 backward than in the Sea-Ducks and Goosanders, 

 so as almost to preclude the possibility of walking, 

 while they are calculated to give their whole pro- 

 pelling force to the body of the bird on the water ; 

 the tarsus is very thin and flattened, the webbed 

 foot very ample, and constructed so as to fold when 



