262 HISTORY OF THE 



My notes all show the iris to be yellowish white, to light red- 

 dish brown; bill and claws dark horn blue, pale at base; cere 

 greenish; legs and feet dull yellow; claws black. 



This bleached variety of the Red-tailed Hawk does not appear 

 to differ from the same in actions or habits. Eggs, according 

 to Eidgway, 2.31x1.80. 



Buteo borealis calurus (CASS.). 



WESTERN RED-TAIL. 

 PLATE XVI. 



Irregular winter sojourner; at times, quite common. I have 

 never noticed the birds in the State during the summer months. 

 They begin to arrive, generally, the last of October, and leave by 

 the last of March. 



B. 20, 24. K. 436J. C. 517. G. 204, 121. U. 337&. 



HABITAT. Western North America: south into Mexico; east 

 to Kansas; casually to Illinois. 



SP. CHAB. Plumage often chiefly blackish (sometimes entirely sooty), ex- 

 cept tail and its upper coverts. Adult: Varying, individually, from a light extreme 

 which is scarcely distinguishable from true B. borealis to a uniform dark sooty 

 brown, through every conceivable intermediate plumage; some melanistic speci- 

 mens have the whole chest and breast rusty or rufous (corresponding to the 

 white area of very light colored birds), but this is wholly obliterated in the com- 

 plete melanism. Young: Darker throughout and more heavily spotted beneath 

 than in true B. borealis, the plumage sometimes wholly dusky (except the tail ), 

 as in the adult. Tail of adult always with a black subterminal bar, and fre- 

 quently with several more or less complete additional bars. (Ridgway.) 



Stretch of 

 Length. wing. Wing. Tail. Tarsus. Bill. Cere. 



Male 19.50 48.50 15.25 8.50 3.10 1.00 .50 



Female... 22.00 51.00 16.50 9.50 3.20 1.10 .55 



Iris brown; bill horn blue; cere greenish yellow; legs and feet 

 yellow; claws black. 



This dark Western race does not appear to differ in habits 

 from the Eastern bird. A set of four eggs, collected May 21st, 

 1878, in Santa Barbara county, California, from a nest in a pop- 

 lar tree, about thirty feet from the ground, measure: 2.23x1. 8G, 

 2.31x1.84, 2.36x1.84, 2.39x1.87; ground color dull bluish to 

 cream white, irregularly spotted and blotched with pale to dark 

 vandyke brown, mixed with markings of light purple brown, 

 all rather oblong in shape, and running lengthwise on the egg; 

 in form, oval. 



