48 BIRDS. ACCIPITRES. Falco. 



ACCIPITRES. 



RAPACIOUS BIRDS. 



I. DIURN7E. Hawks. — Bill covered at the base with a cere, 



in which the nostrils are lodged. Eyes lateral. Outer 

 toe (with the exception of Balbusardus) incapable of ha- 

 ving its position or motion reversed. 



* Macropter^e. Noble Hawks. — Second quill-feather longest; 



the first nearly equal. Bill arched from the base. 



•f Claws flat or grooved on the under side. 

 Falco. 

 Gyrfalco. 



•f-f Claws rounded on the under side. 

 Balbusardus. 



•• Brachypter.e. Ignoble Hawks. — The third or fourth quill- 

 feather longest; the first very short. 



f Tail forked. 

 Milvus. 

 ft Tail not forked. 



1. Space between the bill and eye feathered. 



Pernis. 



2. Space between the bill and the eye naked or hairy. 



a. Bill straight at the base, and bent at the extremity. 



Aquila. 



aa. Bill bent from the base. Tarsi plated. 



b. Ear-feathers forming a collar like the owls. 



Circus. 



bb. Ear-feathers plain. 

 Buteo. 



II. NOCTURM/E. Owls.— Bill without cere. Eyes large, 



directed anteally ; surrounded with a circle of radiating 

 wiry feathers, which serve to cover the base of the bill 

 and auricles. The external toe capable of having its po- 

 sition and motion reversed. On the top of the head, in 

 some species, are two tufts of long feathers, termed horns 

 or ears. 



* Concha of the ear occupying the whole side of the head. The first 



or second quill the longest. Wings about the length of the tail, 



•f- Bill arched from the base. Head with horns. 

 Otus. 



•f f Bill straight at the base. Head destitute of horns. 

 Aluco. 



