FALCONIDJE : VULTURES, FALCONS, HAWKS, ETC. 



619 



plumage with age are great, and render the determination of the species perplexing — the more 

 so since purely individual, and somewhat climatic, color-variations, and such special conditions 

 as melanism, are very frequent. The modes of nesting are various; the eggs as a rule are 

 blotched, and not so nearly spherical as those of owls. The food is exclusively of an animal 

 nature, though endlessly varied ; the refuse of the stomach is ejected in a hall by the mouth. 

 The voice is loud and harsh. As a rule, the birds of prey are not strictly migratory, though 

 .many of them change their abcjdo with much regularity. Their mode of life renders them 

 usually non-gregarious, excepting, however, the vultures and vulture-like hawks, which con- 

 gregate where caniou is plenty, quite like the American Catharfides. There are upwards of 

 300 species or good geographical races, justly referable to about 50 full genera, and divisible 

 into two families — EalconidcB and Pandionidce. 



31. Family FALCONID^ : Vultures, Falcons, Hawks, Eagles, etc. 



Characters as above, ex- 

 clusive of those marking the 

 fish-hawks, Pandionidce, be- 

 yond. No unexceptionable 

 division of the family having 

 been proposed, and the sub- 

 families being still at issue, it 

 may be best not to materially 

 modify the arrangement pre- 

 sented in the earlier edition 

 of this work, further than 

 to separate Pandionidce from 

 Fatconidce ]5roper. 



The Old World Vultures 

 foim a group standing some- 

 what apart froin the rest in 

 many points of superficial 

 structure and habits, though 

 so closely correspondent with 

 ordinary Falconidce, and es- 

 pecially with ButeonincB, in 

 all essential respects, that 

 they can form at most a sub- 

 family Vtdturince (fig. 36.3.) 



Fig. 363. —Tlie Vulture's banquet: illustrating subfamily Tulturinmoi 

 family Falconida, not represented in America. (From Miclielet.) 



They have nothing to do with the American Vultures (suborder Cathartides), with which they 

 have been wrongly united in a family Vtdturidce. They are a small group of some six genera 

 and about twelve species, of ^vhich the most decidedly raptorial is the bearded griffin, Gypaetiis 

 barbatus; other characteristically " vulturine " torms being Vtdtur monachus, Otoyyps auricu- 

 lans, GijpsfulvHS, Neoi^hron percnoirierus, and Gijiiohierax anrjolensis. 



The South American genera, Micrastur and Herpetotlieres, are each described as being 

 so pecuhar as to form a group of supergenerio value, comparable with those termed subfamilies 

 in tlie present w<]rk. Their relationships are with FrdconincB. (Ridgway.) 



The North American Falconidce with which wo have here to do fall in several gi'oups, 

 which I shall call subfamilies, without insisting upon their taxonomio rank, or raising the 

 •question whether the family at large is divisible in this manner. These groups are six in 

 number : 1. CircincB, harriers ; 2. Milvinoe, kites ; 3. Accipitrince, hawks ; 4. Fcdconince, 



