DIVERS. 151 



height ; some are toothed in the tomia, for catching 

 the finny prey as they drive through the waters ; 

 some are fitted for cutting and tearing the carcasses 

 of the larger sea animals , which are often floating 

 dead on the surface ; some are adapted for collecting 

 oil on the surface of the waters ; and others for 

 dabbling in the mud in the shallows. 



Organs so differently formed, and applied to so 

 many purposes in so many ways, render the division 

 of aquatic birds into natural groups no easy matter, 

 though some of the groups are as distinct and well 

 defined as any of those of the land birds. Cuvier 

 arranges them into four tribes. 



The first of these consists of Divers (JBrachyptera, 

 or "short wings"), which have some affinity wdth the 



Diver. 



shortest winged and most aquatic of the bank birds, 

 and they run on, becoming more and more birds of 

 the water, and less birds of the air or the land, till 

 those species are arrived at which can neither fly nor 

 walk. The show of resemblance may be said to run 

 to a termination in this group ; for, as the latter 

 can only swim and dive, and there are no other 

 birds which can do either in greater perfection, there 

 is no point of general character upon which any 

 others can be connected with them. The popular 

 name is also not quite precise, because, though they 



