10 RAPTORES. AQUILINA. 



have been recognised in the Falconida? ; viz. Aguilina, Ac- 

 cipitrina, Falconina, Buteonma, and Milvina, which again 

 are divisible, into groups of still less amount, constituting 

 the genera of the present work *, and all forming a circular 

 series of affinities within themselves. Of these Subfamilies, 

 the Accipitrina and Falconina are the typical forms, possess- 

 ing peculiarities of structure, habits, &c., which either do not 

 exist, or become modified in the others. 



SUBFAMILY AQUILINA. 



THE distinguishing characters of this Subfamily, consist 

 in superiority of size, in having the bill longer and straiter 

 at the base than in the typical Falcons, in which respects 

 they approach nearer to the Vulturine Family ; the fea- 

 thers of the crown of the head and neck are narrow and 

 sharp-pointed, and in some subjects the head and throat are 

 found partially naked. Their limbs are generally short and 

 muscular, and their talons very strong and much hooked. 

 In this subdivision we find the most powerful and destruc- 

 tive birds of the Family, as well as others, which partaking 

 more of the Vulturine form and disposition, are less preda- 

 cious, and frequently content themselves with prey already 

 dead, or, in some instances, with carrion. Towards the far- 

 ther extremity other forms are met with, which connect this 

 Subfamily more immediately with the Accipitrinse and others 

 of the Order. 



* By Mr SWAINSON, in that beautiful and valuable national work, the 

 Fauna Americana Borealis, these Subfamilies are considered as Genera ; 

 the inferior groups (answering to the genera of this work) being distin- 

 guished by the appellation of Subgenus. His remarks upon this Family 

 are highly interesting, and deserving of repeated and attentive perusal by 

 every ornithologist. 



