﻿296 ON THE CLASSIFICATION OF BIRDS. 



to be natural; and it therefore follows,, as a legitimate 

 deduction, that as the insessorial order is circular, so 

 also is the raptorial. 



(242.) In regard to the external affinities of the 

 family, little need be said, since its situation between 

 the vultures and the owls has been universally admitted 

 since the days of Linnaeus. The bearded vulture of 

 the Alps, as already remarked (235.), is an eagle in its 

 habits, food, and many parts of its structure : while 

 several of the Aquilce evince their affinity to the Vul- 

 turidce by their partially naked heads, and by feeding 

 occasionally upon carrion. Some of the buzzards, on 

 the other side of the falconine circle, show the strongest 

 possible affinity to the owls, by their large ears, often 

 surrounded, as in Circus, by a ruff of stiff feathers — 

 their hunting, like the rough -legged buzzards, by 

 twilight — and by the soft lax plumage, seen more par- 

 ticularly in the last-mentioned species. These external 

 affinities, indeed, have been so long known to naturalists, 

 that they would not have been here repeated, did not 

 their admission confirm the analogical demonstration 

 we have just given of the family ; for if this is correct, 

 if follows, that, as the primary divisions of the Falconidce 

 represent the primary divisions of the perchers, they 

 consequently represent those of all the circular groups 

 in the class of Aves. 



(243.) Upon entering more into the details of the five 

 leading generic groups, we shall experience more dif- 

 ficulty, from the causes we have already mentioned, than 

 with almost any other group in the whole circle of 

 ornithology. We have, for several years, assiduously 

 collected, where procurable, all such specimens as were 

 adapted, from their size, to a private museum, and have 

 taken an extensive series of notes regarding such as 

 were only to be seen in other collections ; but these 

 materials are still insufficient to allow of that complete 

 exposition of all the newly proposed genera which it 

 would have been so desirable in this place to furnish. 

 Several of these, indeed, we know only from figures or 



