FALCONS, HAWKS, EAGLES, ETC. 
147 
2 . Claws not all the same length, grooved on under side. 
3. Tarsus feathered to base of toes.Aquila, p. 163. 
3'. 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 
inner webs. Fig. 214. ° 
3. Nostril circular, with conspicuous bony tubercle. 
A" i Falco, p. 165. 
Fig. 215. 3'. Nostril not circular, without bony tubercle. 
4. Tail deeply forked. 
4'. Tail not deeply forked. 
Fig. 217. 5. Tarsus minutely scaled in front 
5'. Tarsus coarsely scaled in front. 
Ictinia, 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. 
. Elanus, p. 148. 
Fig. 218. 
4. Legs feathered to toes. Archibuteo, p. 162. 
4'. Legs not feathered to toes. 
5. Nostrils oblique and linear, slanting forward to cut¬ 
ting edge of bill. Polyborus, p. 171. 
5'. Nostrils not oblique or linear. 
6. Tail decidedly more than two thirds as long as 
wing. 
7. Lores nearly naked . . . Parabuteo, p. 154. 
7'. Lores densely feathered . Accipiter, p. 151. 
6'. Tail not more than two thirds as long as wing. 
7. Primaries exceeding secondaries by less than 
naked front of tarsus . Urubitinga, p. 160. 
7'. Primaries exceeding secondaries by much more 
than naked front of tarsus. 
8. Adults with under parts barred gray and 
white ; wing less than four times as long as 
tarsus. Asturina, p. 161. 
8'. Adults with under parts not barred gray and 
white; wing more than four times as long as 
tarsus. Buteo, p. 155. 
