Western Goshawk 173 



five eggs. These are pale bluish in colour, nearly 

 always unspotted, and average 2*3 x 1"75. 



Western Goshawk. Astur airicapillus striatulus. 



A.O.U. Checklist no 334a — Colorado Records — Cooke 97, pp. 74, 

 204 ; Gilman 98, p. 28. 



Description. — Resembling A. atricapillus, but darker, almost s-^oty 

 above, while below the markings are also much darker and heavier. 

 A young bird is brownish-black above, this colour predominating over 

 the tawny markings ; stripes on the lower parts broader and deeper 

 black, and the thighs with large, often cordate spots. 



Distribution. — Replacing A. atricapillus in the west ; breeding from 

 Sitka south along the coast ranges to about latitude 38'' in California, 

 merging to the eastwards in Colorado with the typical form. 



Most of the Colorado Goshawks are intermediate, though on the whole 

 referable to the eastern form ; a specimen, taken at Sweetwater Lake 

 in Garfield co., February 12th, 1898, by J. T. Meiner, was identified 

 at the United States National Museum as this subspecies ; and it is 

 quite possible that others may be found nearer the western than the 

 eastern bird. 



Genus BUTEO. 



Bill moderate, the cutting-edge of the upi^er mandible slightly 

 festooned ; nostril oval, without a central bony tubercle ; wing rather 

 long and pointed, the outer three or four primaries emarginated on the 

 inner web, the sixth to the eighth the longest ; tail rather short from 

 I to I of the wing, even or slightly rounded ; tarsi half feathered, 

 scutellated in front, reticulate on the sides and posteriorly ; melanism 

 very common. 



The genus contains the Buzzards, as they are generally called in 

 Europe, and embraces numerous species found all over the world, 

 excepting Australia. There are four common species in the United 

 States, two of which commonly occur in Colorado. I have included 

 B. lineatzis elegans in the key, as it is reported by Cooke to have been 

 soen in Colorado by Breninger though it has never been taken. 



IVEY OF THE SpECIES. 



A. Four outer primaries emarginated on the inner web. 

 a. Outer webs of primaries not spotted with white, 

 a^ Above dark brown and tawny, without white. 



a^ Tail in adult rich rufous, with a subterminal band of black. 



B. b. calurus, p. 174, 

 b^ Tail mottled with greyish, rusty, white and dusky. 



B. b. harlani, p. 176. 



