FALCONID&. 



223 



naked portion of tarsus in front; 

 lores densely feathered. 



Accipiter. (Page 227.) 

 k 1 . Depth of bill at base decidedly less 

 than chord of culm en; middle 

 toe much shorter than naked 

 portion of tarsus in front ; lores 

 nearly naked. 



Parabuteo. (Page 228.) 



f . Tail not more than two-thirds as long as 



wing. 



k 1 . Primaries exceeding secondaries by 



less than length of naked portion 



of tarsus in front. 



Urubitinga. (Page 238.) 



k 2 . Primaries exceeding secondaries by 



much more than length of naked 



portion of tarsus in front. 



P. Wing less than four times as 



long as tarsus. 



Asturina. (Page 239.) 

 P. Wing more than four times as 

 long as tarsus. 



Buteo. (Page 229.) 

 e*. Tarsi densely feathered in front and on sides, down to base of 



toes Archibuteo. (Page 240.) 



(P. Wing more than 18.00. 



e 1 . Tarsus densely feathered, all round, down to base of toes. 



Aquila. (Page 241.) 

 e 5 . Tarsus naked, all round, for lower third, or more. 



/*. Wing much rounded (fifth to seventh quills longest, the 

 first shortest), the secondaries very large and broad, 

 reaching nearly or quite to tips of quills ; tail nearly 

 as long as wing ; occiput conspicuously crested ; feet 



enormously developed Thrasaetus. (Page 242.) 



/". Wing pointed (third to fifth quill longest, the first longer 

 than ninth), the secondaries only moderately devel- 

 oped, their ends falling far short of tips of quills ; tail 

 less than two-thirds as long as wing; occiput not 

 crested ; feet moderately developed. 

 g\ Tail rounded, consisting of 12 feathers. 



Haliseetus. (Page 242.) 

 g*. Tail graduated, or wedge-shaped, consisting of 14 



feathers Thalassoaetus. (Page 243.) 



Nostril small, circular, with a conspicuous central bony tubercle, or else 



