316 On the Affinities of the Falconida. 



belonging to several different genera. In the genus Spizae- 

 tus we have some species crested and others not, and at the 

 same time both of them possessing the essential generic 

 characters. Moreover from the characters assigned to his 

 genus Aquila, the wedge-tailed eagle (Falco fucorus, Cuv.) of 

 New Holland is excluded ; little more than the upper third 

 of whose tarsus is feathered. But the characters of length- 

 ened wings and feathered tarsus are equally common to the 

 genera Morphnus and Buteo. As for locality, though his 

 observation in one point of view is correct, in as far as 

 the metropolis of the eagles is the Old world, yet still 

 we find the most typical species also in the New ; thus 

 the Aquila chrysaetos, Haliaetus opipagus, and H. leu- 

 cocephalus are also found to occur in North America. 

 From what we have just stated, it therefore appears that 

 we have no character (unless the proportional length of 

 the quill feather, which we shall afterwards examine) to 

 distinguish an Aquila from Morphnus or Buteo. Nor 

 is the genus Haliaetus altogether done away with, it being 

 placed in the sub-family Accipitrinae upon very erroneous 

 grounds. Thus the characters assigned to this sub-family 

 are, " Bill short, suddenly curved from the base ; the upper 

 mandible armed in the middle of the margin with a large, 

 obtuse, rounded tooth or festoon ; under mandible truncated 

 at the tip ; cere moderate ; feet moderate ; tarsus in 

 general smooth, naked ; middle toe lengthened ; hinder not 

 much shorter than the inner; anterior claws very unequal, 

 the inner being almost twice the size of the outer, and 

 nearly as strong as the hinder. Head small ; wings short ; 

 the quills internally emarginate at their base; tail rounded. 

 In regard to the above characters, in many instances they 

 do not agree with the genera ; thus, as already stated, in 

 many species of the genus Accipiter there is no festoon, the 

 cutting edge of upper mandible being quite smooth. In 

 the genus Ictinia the tip of the under mandible is not 



