166 AVES. 



faculty, we may consider them as exclusively attached to the surface 

 of the water: their plumage is extremely dense, and its surface fre- 

 quently polished, presenting a silvery lustre. They swim under wa- 

 ter, using their wings with almost as much effect as though they 

 were fins. 



CoLYMBUs, Lin. 



The only particular character of the Divers is a smooth, straig-ht, compressed 

 and pointed bUl, and linear nostrUs; but the differences in the feet have 

 caused them to be subdivided. 



PoDicEPs, Lath. 



The toes of the Grebes, instead of being palmated, arejwidened hke those 

 of the Coots, the anterior ones only being united at base by membranes. 

 The middle nail is flattened, and the tarsus strong-ly compressed. The 

 semi-metallic lustre of their plumage has caused it to be occasionally em- 

 ployed as fur. Their tibia, as well as that of the succeeding subgenera, 

 is prolonged above into a point which gives a more efficient insertion to 

 the extensors of the leg. 



These birds hve on lakes, &c., and build among the rushes. In certain 

 circumstances, it appears that they caiTy their young ones under their wings. 

 Their size and plumage are so much changed by age, as to have caused an 

 improper multiphcation of species. M. Meyer reduces those of Europe 

 to four. 



Col. cristatus, Gm. (The Crested Grebe) is the size of a duck; blackish- 

 brown above, silver-white beneath; a white band on the wing; it acquires 

 with age a double black tuft, and the adults have, in addition, a broad red 

 colerette on the upper part of the neck edged with black. 



Mehgtts, Briss. — Eudttes, Illig.(l) 



The true Divers have the feet of ordinary Palmipedes, along with all the 

 forms of the Grebes, that is, the anterior toes are united to their ends by 

 membranes, and are terminated by pointed nails. They are northern birds, 

 which rarely breed in France, where they arrive in winter, at which season 

 is occasionally seen on the coast 



Col. glacialis, L.. (The Great Northern Diver.) The adult is two feet 

 six inches in length, its head and neck black, changing to a green with a 

 whitish collar; back, a blackish brown dotted with whitish; white beneath; 

 the lower mandible, which has a slight curve upwards, is marked by a 

 g^roove beneath. 



Uria, Briss. 

 The Guillemots have a bill, which, though of the general form of the pre- 



(1) JHergus (diver), the Latin name of some sea-bird difficult to determine. 

 Eudyfes, a Greek word composed by Illiger, has the same meaning. 



