LAND BIRDS. 



267 



lasted several days and appears to take place late in August and early in 

 September every year. 



TECHNICAL DESCRIPTION. 



Adult male: Uniform dark bluish gray or slate blue above, the feathers of the occiput 

 pure white beneath the surface; under parts white, the throat narrowly streaked and the 

 rest heavily barred with reddish brown; primaries blackish on outer webs, bluish white 

 barred with black on inner webs, the five outer ones emarginate on the inner webs; tail 

 colored like the back, but with about five blackish cross-bars, the tip narrowly white. 

 Tail square or slightly emarginate at tip; bill black; legs and feet yellow; iris reddish brown. 

 Length 10 to n.50 inches; wing 6.10 to 7.10; tail 5.80 to 6.10. Adult female: Similar 

 in color to the male, but decidedly larger. Length 12.50 to 14 inches; wing 7.80 to 8.80; 

 tail 6.60 to 8.20. Immature: Without any slate blue, the upper parts larownish, the 

 feathers mostly edged with rufous and the tertiaries and scapulars with many partly 

 concealed, large, white spots; under parts white, everywdiere streaked with pale brown, 

 many feathers with sharp shaft lines of dark brown or blackish. 



136, Cooper's Hawk. Accipiter cooperi (Bonap.). (333) 



Synonyms: Pigeon Hawk, Chicken Hawk, Quail Hawk, Blue Darter, Swift Hawk.- 

 Falco cooperii, Bonap., 1828. — Accipiter cooperi, Gray, 1844, and authors generally.- 

 Astur cooperi, Jard., DeKay, and some others. — Nisus cooperi, B. B. & R., 1875. 



Fig. 70. Cooper's Hawk, .\dult. 

 •'roin Baini, Brewer & Rids^way's North American Binis 



Little, Brown t»i Co. 



Figures 70 and 71 . 



With nearly the same proportions as the Sharp-shinned Hawk, but 

 averaging decidedly larger, with heavier legs and feet, and the tail rounded 

 instead of square. In coloration the two arc very similar, and there is the 

 same general diffci-ence l)etween adults and immature birds. 



Distribution. — North America from southern British America soutii to 

 southern Mexico. Breeds throughout its range. 



Probably, all things considered, our most abundant hawk. It is found 

 in all parts of the state, and in all seasons of the 3'ear, except during two or 

 three of the coldest months. It nests everywhere throughout the state, 



