416 Mr. N. A. Vigors on the Natural Affinities 



natural arrangement, cannot be placed in a different family from 

 Gallinula, nor Podiceps in a different one from Colymhus. It is 

 not easy, I must confess, to draw a decided line of partition be- 

 tween orders so closely assimilated as the Grallatores and Nata- 

 tores. Perhaps the plan most accordant with nature would be 

 to divide the above Aquatic Birds, according as they frequent 

 the fresh or inland waters, or generally inhabit the ocean. 

 The approaching groups of each division would of course par- 

 tially encroach upon the domains of the other ; and while the 

 extremes of the oceanic birds would be occasionally found in 

 inland stations, those of the grallatorial birds would sometimes, 

 on the other hand, gain their support from the ocean, but on the 

 sea-shore, or not far distant from land. Such a view would 

 go far to restore the genera Fulica and Phalaropua, whose sta- 

 tion has been so often disputed, to their original place among 

 the Waders, where they were arranged by Linnaeus. We may 

 thus observe, that the family of Grallatores, which approaches 

 the Natatores by their swimming habits, will lead on in a 

 regular succession from Ballus, Linn., to Gallinula, and Por- 

 phyria, Briss.; thence to Fulica, Linn., and Podoa, 111.; which 

 last genus exhibits a striking approach, in the general con- 

 struction of its neck, body and tail, to the family of Anatida, 

 that forms one of the extremes of the natatorial birds. Some of 

 these, on the other hand, as the genus Anser, evince in the length 

 of their neck and tarsi and the forward position of their legs, 

 together with a greater compression of bill than is found among 

 the AnatidcE in general, a corresponding approach to the Ral- 

 lidcE, or extreme subdivision of the Grallatores. The genus Ce~ 



the typical oceanic or true swimming and diving birds, the other to those which barely 

 approach them. The system which, without regard to their general structure, unites 

 these discordant groups into one, and separates them from all other birds, — merely be- 

 cause the webs that border the toes, although not even similar in construction, (for in 

 one group they are eraarginated, in the other entire,) are not united, — is the most arti- 

 ficial with which I am acquainted. 



reopsis 



