Appendix, 



15. Marsh-Hawk; Circus hudsonius (lAnn.'), 

 Length of male about eighteen, of female twenty 



inches. The white upper tail-coverts are a 

 characteristic mark o^ this species. Male in full 

 plumage bluish gray above, generally mottled 

 with brown; outer flight feathers brownish 

 black; tail grayish with several brown bars. 

 Under parts white, bluish on breast, spotted 

 and barred with reddish brown. The immature 

 male resembles the female, more or less perfectly 

 mottled with rusty. The latter is brown, 

 darker above, and pale below, where it is streaked 

 with reddish brown. A generally distributed 

 and common species about marshy places. 



16. Sharp-shinned Hawk; Accipiter f/^/i?;^ ( Wils. ). 

 A small but destructive species. Length of male 



eleven, of female thirteen inches. In adult 

 plumage the upper parts are dark slaty (often 

 tinged with brownish) and the under parts 

 white, heavily barred crosswise with light 

 reddish brown. The immature birds are dark 

 brown above and white below, streaked length- 

 wise with brown. Tail with dark brown bars. 

 Chiefly a winter visitant in California, although 

 a few summer in the high Sierras. 



17. Cooper's Hawk; Accipiter cooperii (^Bonap.^ . 

 Almost exactly Hke the preceding except for its 



much larger size. Length of male fifteen and a 

 half, of female nineteen inches (average). It 

 differs in adult male in having the head blackish 

 brown, in marked contrast to the slaty color of 

 the back. Fairly common in the valleys in win- 

 ter, and breeding in the Sierra Nevada Mountains, 

 where, however, it does not seem to be abundant. 



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