228 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



of the sumac. The eggs, which were taken on April 30, three in number, 

 contained larg embryos." 



I met with the nest of this Hawk on two occasions only during the 

 spring of 1878, in the vicinity of Camp Harney, Oregon, where it is a summer 

 visitor. I found the first one on April 17, 1878, and as the bird was unknown 

 to me, shot the female, whose lower parts were of a uniform chestnut red 

 throughout, and proved to be of this race. The nest was placed in a young 

 pine on some limbs close to the top and the trunk of the tree, near the sources 

 of Archies Creek in the foothills of the Blue Mountains and on the outskirts 

 of the heavy timber. It was principally composed of sagebrush twigs, lined 

 with pine needles, the inner bark of juniper trees, and a few green willow 

 twigs with the leaves on. It measured about 18 inches in outer diameter and 

 about 6 inches in depth. Inside it was about 8 inches in diameter by 2 inches 

 deep. It contained two handsome fresh eggs, and another would have been 

 laid, as I found on skinning the parent. 



Oil May 6, during another visit to this locality, I discovered a second 

 nest of this race still farther up this creek. This was placed in a tall juniper 

 tree, likewise near the trunk and about 20 feet from the ground, composed 

 of similar materials, and contained a single egg. 



The principal call note when disturbed about its nest is a shrill "yee-ak, 

 yee-ak," uttered rapidly and in a high key. 



The number of eggs to a set varies from two to five ; sets of three seem 

 to be most frequently found. Judging from the limited number of these 

 eggs seen by me, they appear to be not as heavily blotched and spotted as 

 are those of B. lineatus, and the neutral tinted shell markings, such as pearl 

 gray and lavender, predominate in them over the bolder brown and russet 

 markings. Otherwise they do not differ materially in size, shape, or general 

 appearance from the eggs of the Red-shouldered Hawk. 



The average measurement of six eggs in the U. S. National Museum 

 collection is 54 by 43.5 millimetres. The largest of these eggs measures 55.5 

 by 44.5, the smallest 53 by 43 millimetres. The type specimen, No. 20746, 

 from a set of two, Bendire collection (PI 6, Fig. 9), was taken by the writer, 

 on April 17, 1878, near Camp Harney, Oregon. 



79. Buteo abbreviatus CABANIS. 



ZONE-TAILED HAWK. 



Buteo abbreviatus CABANIS, in Schomburgk, Reise in British Guiana, in, 1848, 739. 



(B , C 353, R 440, C 522, U 340.) 



GEOGRAPHICAL RANGE: Middle America ; north to Lower and southern California, 

 Arizona, Texas, etc. ; south to northern South America. 



The breeding range of the Zone-tailed Hawk is rather a restricted one 

 within our borders. As far as is yet known it is confined to the southwestern 

 portions of the United States, from Comal and Presidio Counties in central 



