DIVERS. 



90 



words, they are web-footed. Their feet are made for natation, 

 that is, they are placed far back on the body, an 1 sustained 

 by strong, compressed tarsi. A close, lustrous plumage imbued 

 with an oily fluid, and a thick down next to the skin, protect 

 them against the water upon which they dwell. They are the 

 only animals of this class, in which the neck exceeds and some- 

 times very much the length of tie feet, f >r the reason that when 

 swimming on the surface of the water, they often have to seek 

 animals upon which they feed in its depths. The localities which 

 they inhabit, removes most of them from the empire of man, and 

 in many respects even from the investigation of naturalists Birds 

 of this order generally possess a system of organization which is 

 strong and appropriate for extensive flight ; their sternum is very 

 long, affording ample protection to most of their viscera, and has 

 but one notch or oval hole on each side, which is tilled by mem- 

 brane, so that this bone affords a wide surface for the attachment 

 of the depressor muscles of the wings. This order is divided into 

 four families according to the fallowing characters : 



(Families.) 



Having excessively sh^rt wings, and the legs 

 placed so for ba k, that thny are oh iged, when on 

 land, to pres rve an almost vertical position. They 

 fly little, or not at all. 



Having the 

 wings of ordi- 

 nary length, or 

 even very long, 

 and the feet so 

 pi iced as to ena- 

 ble the animal to 

 walk when in a 

 horizontal posi- 

 tion. 



C The thumb free, 

 The beak < orwnnUng. Wings 

 horny. ^ excessively long. 



f The thumb united 

 j to the other toes by 

 | a common mem- 

 j^brune. Wings long. 



BRACHYPTKR.E. 

 or 



DIVERS. 



LONGTPENNES. 



TOTIPALMATA 



The beak covered by a soft ~i 

 skin and the ed.es furnished I LAMELLIROSTRE8 . 

 with transverse lamellae, or very j 

 fine teeth. 



FAMILY OF BRACHYPTF.RJE, OR DIVERS 

 2. They have the legs placed farther back than all other birds, 

 which renders it laborious for them to walk, and generally obliges 

 them to keep in an erect position when on land, (Plate 6, fig. 

 I,arad2.) As most of them fly badly, and as many of them 

 cannot even fly at all, in consequence of the extreme shortness 

 of their wings, they maybe regarded as belonging, almost exclu- 



2. What are the characters of the Bracbypterse ? What are their habits ? 

 How is this family divided ? 



