171 KEY TO THE BIRDS OF EASTERN NOKTH AMERICA. 



Section 1. Fourth primary, longest; four or five outer 

 primaries, emarginate or notched ; tarsus, entirely 

 feathered ; upper tail coverts, not white. 



Thighs, tawny, more or Less -in-.-iki-J <: hanvd 



American Rough-legged Hawk. 



Archibuteo Ingopus scincti-johannts. 



See No. 2sl . 



(ieneral plumage. -only hrown or hlaek (hlaek 



American Rough-legged Hawk. 

 Ari'liiiuiii'ii iinjiijiiin sanetirjohannit, 



See No. 281 . 

 Thighs, tinned \viili deep rufous with muneron-; luirs. 



Ferruginous Rough-legged Hawk. 

 Archibuteo ferrugineus. 



See No. -2x-2. 



Section 8. Fourth primary, longest ; three outer primaries, 



emarginate or notched. 



Tar-ii-. partly tVnthi-n-il : throat, whiU; (adult); tliroat, tawny or biiff(iinniature). 



Swainson's Hawk. 

 Buteo swainsoni. 



S.-e Xo. -277. 



Group 6. Wing, 17 to 21 inches long. 



Section 1. Third primary, longest; tarsus, wholly 



feathered. 



Basal j-orii-.n o| inner \\-rh <!' primaries, largely white, without bars; thighs, 

 tawny or hull', more or less barred ; tarsus, thickly feathered. 



American Rough-legged Hawk. 

 . irchibuteo lagopiu unncti-johcinnts, 



See \... -jsi. 



I'.a-al portion of inner weh of primaries lar-rely white, without bars; tlii-h-. 

 tiiiLT'-'l \\itli il.-rp rnions heavily barred. 



Ferruginous Rough-legged Hawk. 



Ai'i'liiliiiti-n 1'< ri'in/i in us. 



See No. liS-_>. 



