258 AVES: KAPTOEES. XLI. 



brown. L. 12. W. 7. T. 6. N. Am.; abundant; a small but 

 courageous hawk. The species of this genus are more destructive 

 among poultry than any other hawks. (Lat., swift.) 



808. A. cooperi Bonaparte. CHICKEN HAWK. Tail rounded ; 

 tarsus never booted; colors similar, more blue, the top of head 

 darker, the tail more plainly white tipped. L. 18. W. 10. T. 8. 

 N. Am., common. (To Wm. Cooper, of New York.) 



aa. Tarsus feathered about half way down in front, the feathers scarcely sep- 

 arated behind. (Astur Lace'pede.) 



809. A. atricapillus (Wilson). GOSHAWK. Chiefly slate blue 

 with white superciliary stripe ; lower parts white, finely barred 

 with brown; tail with four dark bars. L. 24. W. 14. T. 11. 

 Northern, S. to U. S. in winter. (Lat., black-haired.) 



421. BUTEO Cuvier. (Lat. buzzard, as these hawks are called 

 in England.) 



a. Outer web of primaries without white, buffy, or ochraceous spots. 

 b. Four outer primaries emarginate on inner web. 



c. Head and neck uniform dark sootj^ brown, or streaked with white, 



never with buffy or reddish. 



810. B. harlani (Audubon). BLACK HAWK. Tail irregularly 

 mottled with grayish, rusty, white, or blackish and with a dark 

 band near tip ; general color usually very dark but variable. L. 

 21. W. 16. T. 10. S. W., E. to III, scarce. 



cc. Head and neck more or less streaked with ochraceous or rusty red. 



811. B. borealis (Gmelin). HEN HAWK. RED-TAILED BUZ- 

 ZARD. Dark brown ; much barred and streaked ; tail in adult 

 bright chestnut red above, with a narrow black bar near its tip. 

 L. 23. W. 15J. T. 8. N. Am. common, replaced W. by var. 

 calurus Cassin, dark brown, sometimes uniform. 



bb. Three outer primaries emarginate on inner web. 



d. Wing more than 13. 



812. B. swainsoni Bonaparte. SWAINSON'S BUZZARD. Gray, 

 variously streaked, usually a bright chestnut or brownish area on 

 breast ; wings dusky ; tail with nine or ten narrow dark bars ; 

 variable. L. 20. W. 16. T. 8. W. U. S., E. to Ind. and Mass. 

 (To Wm. Swain son.) 



dd. Wing less than 12. 



813. B. latissimus (Wilson). BROAD-WINGED HAWK. Brown 

 above, whitish or fulvous below, variously streaked and barred ; 

 conspicuous dark cheek patches ; tail with broad dark bands alter- 

 nating with narrower pale ones, white-tipped ; lower parts brownish 

 with whitish spots ; in young whitish with darker streaks. L. 18. 



