628 



PATAGONIAN EXPEDITIONS I ZOOLOGY. 



defined on the silvery white of the rest of the under surface, the abdomen, 

 the sides, thighs, flanks, the feathers about the vent and some of the under 

 tail-coverts (in this individual many of the feathers of the breast band are 

 tipped just at the end with silvery white ; probably a sign of immaturity, 

 as most birds in this phase lack this decoration) ; the feathers are long and 



FIG. 317. 



Buteo melanoleucus. Foot of adult female. One-half natural size. 



silky in character and each is crossed by seven or more wavering bars or 

 lines of pale ashy brown ; the tail-coverts nearest the body are like the 

 rest of the under surface, but the posterior half of these feathers, which are 

 so long as to reach nearly to the ends of the outer rectrices, are barred 

 heavily and evenly black and white ; the thighs are barred like the rest of 

 the under surface with narrow, pale, wavering lines of brownish ash. 



There appear to be no detailed field notes as to the color of the bill, 

 cere, iris or feet and legs of this hawk. 



Adult female : No. 7885 P. U. O. C, Halliday's Ranch, southeastern 

 Patagonia, I5th June, 1896, J. B. Hatcher. 



