FALCONS, HAWKS, EAGLES, ETC. 



147 



2'. Claws not all the same leng-th, grooved on under side. 



3. Tarsus feathered to base of toes Aquila. p. 163. 



o. Tarsus not feathered to base of toes .... Haliaeetus. p. 165. 



1'. Wing- less than 17. ■ ■■ ■-- , 



2. Wing- with only one or two quills cut out on ^ (X\}iAi{U)^ir-, ^ 



inner webs. 



Fig. 214. 



3. Nostril circular, with conspicuous bony tuberch 



Falco, p. 165. 



Fig. 21 



Fig. 215. 3'. Nostril not circular, without bony tubercle. 



4. Tail deeply forked. 



Elanoides. p. 148. 



Fig. 216. 

 4'. Tail not deeply forked. 

 Fig. 217. 5. Tarsus minutely scaled in front . . Elanus, p. 148. 



5. Tarsus coarsely scaled in front. 

 Ictiilia, p. 149. 

 2'. Wing with three to five quills cut out on inner 

 webs. 

 3. Face with owl-like ruff of stiff" feathers. 



Circus, p. 150. 

 3'. Face without owl-like ruff of stiff feathers. 



4. Legs feathered to toes Archibuteo, p. 162. 



4'. Ijegs not feathered to toes. 



^^^ 5. Nostrils oblique and linear, slanting forward to cut- 

 ting edge of bill Polyboius, p. 171. 



Fig. 219. 5'. Nostrils not oblique or linear. 



6. Tail decidedly more than two thirds as long as 

 wing. 

 7. Lores nearly naked . . . Parabiiteo. ]>. l.'")4. 

 7. Lores densely feathered . Accipiter, p. 151. 

 6'. Tail not more than two thirds as long as wing. 

 7. Primaries exceeding .secondjirics by less than 

 naked front of tarsus . Urubitinga. p. 160. 

 7 . Priniaries exceeding secondaries by niiu-h more 

 tban iiaki'd front of tarsus. 

 8. Adults with under ])arts barred gray and 

 wliiti' ; wing less than four times as long as 



tai'sus Asturiiia. p. Itil. 



8. Adults with under parts not barred gray and 

 white ; wing more tban four tinws ;»s long as 

 tarsus Buteo, p. 155. 



