FAMILY FALCONID^E. HAWKS, FALCONS, EAGLES, ETC. 171 



Section 2. Second primary, longest; first and second 

 primaries, emarginate or notched. 



Back, entirely brown; belly, white, without streaks; under tail coverts, pure 

 white ; tarsus, nearly bare. 



Fish Hawk. 



Pandion kaliaetns carolinensis. 

 See No. 298. 



Back, brown; belly, brovn; under tail coverts, 'X>t white. 



Black Gyrfalcon. 



Fdlco rustic olns obsoletus. 

 See No. 289. 



Back, slaty brown and white; under tail coverts, spotted or marked with dusky. 



Gray Gyrfalcon. 



Ful co rusticolus, find races. 

 See No. 287. 



Back, white, or white streaked with slaty brown ; under tail coverts, white. 



White Gyrfalcon. 



Falco islandus. 

 See No. 286. 



Section 3. Third primary, longest. 



Four outer primaries, notched; basal portion of inner webs of primaries, largely 

 white, without bars ; thighs, tawny or buff, more or less barred; tarsus, 

 thickly feathered. 



American Rough=!egged Hawk. 



Archibuteo lagnpus sancti-johannis. 

 See No. 281. 



Four outer primaries, notched ; basal portion of inner webs of primaries, largely 

 white, without bars ; thighs, tinged with deep rufous, heavily barred ; tarsus 

 thickly feathered. 



Ferruginous Rough=Iegged Hawk. 



Archibuteo furrnyineus. 



See No. 28'2. 



General plumage, entirely sooty brown, or black; four outer primaries, notched; 

 primaries and tail, with more or less white, or gray ; tarsus, thickly feathered. 



American Rough=legged Hawk (black plumage). 



Archibuteo layopiis sancti-johannis. 

 See No. 281. 



