HAWKS, EAGLES, AND KITES 289 



6. Wing over lO'OO. 



6 1 . Second primary longest. 



6 2 . Tail generally over 9 '00. 



6 3 . Lower tail-coverts immaculate white. 



353. WHITE GYRFALCON. 



6 4 . Lower tail-coverts always more or less marked with dusky. 



354. GRAY GYRFALCON and Races. 

 c 2 . Tail under 9 '00. 



c 3 . Tarsus shorter than middle-toe without nail, upperparts 



blackish 356. DUCK HAWK. 



c 4 . Tarsus longer than middle-toe without nail, upperparts 



brownish 355. PRAIRIE FALCON. 



c 1 . Third or fourth primary longest. 



c 2 . Upper tail-coverts white 331. MARSH HAWK. 



c 3 . Upper tail-coverts brownish . . . 334. GOSHAWK (Im.). 

 B. Outer primary generally one color, base sometimes whitish or with 

 a few imperfect bars. 



a. Tarsus entirely bare, scales on its front large, rounded. 



362. AUDUBON'S CARACARA. 



b. Tarsus not entirely bare. 



b 1 . Tarsus entirely feathered . . 348. FERRUGINOUS ROUGH-LEG. 

 c 1 . Tarsus partly feathered. 



c 2 . Scales on front of tarsus, small, rounded . . . 364. OSPREY. 

 d 2 . Scales on tarsus not rounded, square. 



d 3 . Three outer primaries emarginate or "notched."* 



d 4 . Wing under 12*00. . 343. BROAD-WINGED HAWK (Im.). 

 d 5 . Wing over 12*00. . . . 342. SWAINSON'S HAWK (Im.). 

 e 3 . Four outer primaries emarginate or "notched, "f 



e 4 . Upper tail-coverts pure white . . 331. MARSH HAWK. 

 e 5 . Upper tail-coverts not pure white; wing under 13*50; lesser 

 wing-coverts conspicuously margined with rufous. 



339. RED-SHOULDERED HAWK (Im.). 



e 6 . Upper tail-coverts not pure white ; wing over 13*50; lesser 

 wing-coverts not conspicuously margined with rufous. 



337. RED-TAILED HAWK and races. 



2. Underparts with more or less numerous cross-bars. 



A. Front of tarsus with sharply defined scales. 



a. Scales on front of the tarsus numerous, rounded. 



a 1 . Wing under 15*00 356. DUCK HAWK. 



a 2 . Wing over 15*00 362. AUDUBON'S CARACARA 



b. Scales on front of the tarsus sharply defined, transverse, more or less 



square. 



6 1 . Four or five outer primaries emarginate or "notched.''! 

 b 2 . Tail white at the base and tipped with whitish. 



330. EVERGLADE KITE. 



6 3 . Tail rufous, with sometimes a black band near the end. 



337. RED-TAILED HAWK (Ad.) and Races. 



6 4 . Tail black or blackish, with four to six white or grayish cross- 



bars 339. RED-SHOULDERED HAWK (Ad.). 



339a. FLORIDA RED-SHOULDERED HAWK (Ad.). 

 fe 6 . Tail 10*00 long, gray, with several indistinct blackish bands. 



334. GOSHAWK. 



c 1 . Three outer primaries emarginate or "notched."* 

 c 2 . Tail with two or three broad whitish bars. 



343. BROAD-WINGED HAWK (Ad.). 

 c 3 . Tail with numerous narrow, indistinct blackish bars. 



342. SWAINSON'S HAWK (Ad.). 



* See Fig. 88. t See Fig. 87. 



