Western Goshawk 173 
five eggs. These are pale bluish in colour, nearly 
always unspotted, and average 2°3 x 1°75. 
Western Goshawk. <Astur atricapillus 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 sooty 
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 upper 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 
3 to 3 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. lineatus elegans in the key, as it is reported by Cooke to have been 
seen in Colorado by Breninger though it has never been taken. 
Key oF THE SPECIES. 
A. Four outer primaries emarginated on the inner web. 
a. Outer webs of primaries not spotted with white. 
alt 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, 
