296 



NORTH AMERICAN BIRDS. 



lining near the edge; under surface of primaries white anterior to their emargination, 

 finely mottled with ashy, and witli indistiiiot transverse l>ands terminally. Fourth quill 

 longest; third shorter than fifth; second equal to sixth; first equal to tenth. Wing, 

 15.75 ; tail, 9.10 ; tarsus, 3.25 ; middle toe, 1.70. 



This remarkable Hawk is certainly not to be referred to llie IS. borealis, as has been 

 suggested, the proportions of the two being quite dififerent, while tliecc is no similarity of 

 plumage. In plumage, Buteo cooperi very closely resembles the adult of Archibuleo fer- 

 rugineus, and the suggestion has been made that it is a hybrid between this and the Red- 

 tail. The markings of the head, and the general tint of the upper parts, are almost 

 precisely as in the former bird, while the tail is exactly similar in character of markings, 

 the only difference being the more reddish tinge and black subterminal band, which are, 

 in fact, the only characters approximating it to the Buteo borealis. The feet are, however, 



Buteo cooperi (adult). 



very much stronger than in the A. /errugineus, while the tarsus is very much longer than 

 in boreali.t. scarcely more so, however, than in the former. The black patch on the lining 

 of the wing, however, is a feature shared by neither of these birds, being one entirely 

 peculiar to the Buteo cooperi. But one specimen — the one described above — is known 

 to have been obtained. Mr. .1. A. Allen, in his " Notes on some of the Rarer Birds of 

 Massachu.setts " (.see "American Naturalist," Vol. Ill, p. 518, and a separate paper, p. 14), 

 mentions the capture of this species near Cambridge, Mass., but probably did not actually 

 see it. The specimen in question being in the posse.s.sion of Mr. C. J. Maynard, he kindly 

 sent it to the Smithsonian Institution. On examination, it proved to be a young Buteo 

 lineatus, differing from the average in somewhat lighter colors. 

 Hab. Santa Clara County, California. 



