60 AVES. 



GENUS AQUILA, Briss. Eagle. 



Tarsus as short, or but little longer, than the middle toe ; 

 beak straight at the base, and bending only at the point. 

 Two remarkable subgenera the Eagle proper, Aquila, Cuv., 

 which has the tarsus feathered down to the root of the toes, 

 and the Fisher Eagle, Halisetos, Savig., which has the tarsus 

 feathered only in the upper half. 



" / ** ' 



GENUS ASTUR, Bechst. Goshawk and Sparrowhawk. 



Wings shorter than the tail; but the beak curved from its 

 base. 



GENUS MILVUS, Bechst. Kite. 



Tail forked; wings excessively long; beak small; tarsi 

 short ; nails feeble. 



GENUS BUTEO, Bechst. Buzzard. 



Wings very long; tail equal ; feet strong ; interval between 

 the eyes and beak naked ; the beak curved from its base as 

 in the preceding. 



FAMILY II. NOCTURNAL BIRDS. 



Large head ; eyes very large, directed forwards and sur- 

 rounded with a circle of fringed feathers, the anterior of which 

 cover the cera of the beak, and the posterior the opening of 

 the ear ; pupil of the eye very large ; exterior toe of the foot 

 free, and capable of being directed at will forwards or back- 

 wards; apparatus of flight weak; fourchette having little 

 strength ; feathers with soft beards covered with fine down. 

 Form but one genus. 



GENUS STRIX, Lin. 



They may be divided by their tufts, the size of their ears 

 and the extent of the circle of feathers around their eyes. 



SBBGENUS OTUS, Cuv. Horned Owls. 



Have two tufts of feathers (aigrettes) on the forehead which 

 they can erect at will ; the conch of the ear extending in a 

 semicircle from the beak to the top of the head ; beak curved ; 

 feet feathered to the nails. 



