THE BIRDS OF CLIPPERTON AND COCOS ISLANDS 



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margins, the feathers of the back, scapulars, rump and the upper tail 

 coverts with wider, and the greater and middle wing coverts with very- 

 wide, buffy, almost rufous, margins. Rectrices sooty-brown, with 

 very narrow edgings and wider tips of buff. Feathers of lower parts 

 blackish-brown centrally with wide ashy margins on the throat, and 

 buffy margins on the breast, sides and crissum, and with whitish 

 margins on the belly where the dark central areas of the feathers are 

 almost obscured. Under wing coverts and inner edges of bases of the 

 wing quills whitish. Bill blackish-brown above, pale horn-brown 

 beneath. Feet dark brown. 



Toung Male. — Cat. No. 1401, Stanford University Museum, from 

 Cocos Island, June 30, 1S99. Similar to the last, but the pale 

 edges of the feathers of the back wider and olive-buff in color, this 

 color almost obscuring the black central areas of the feathers in the 

 middle of the back. Below, ground color almost uniform pale olive- 

 yellowish ; the breast streaked with dark brown. Sides and flanks 

 washed with buff. Upper mandible dark brown, lower mandible 

 brownish toward tip, yellowish at base. 



Im7nature Fe?)iale. — We have two females in the plumage described 

 by Townsend as adult females, which plumage is exactly the same as 

 that of the "young" male just described. These female specimens 

 certainly have the appearance of being immature birds, having the 

 upper mandible very pale brown and the lower pale yellowish. If 

 these are not mature, then the adult female is not known. It will 

 probably be found to resemble in plumage the " immature" male de- 

 scribed above, and to have the bill entirely black, as is the case with 

 the females of the Galapagos genus Geospiza. 



The collection contains 5 specimens, being i adult male, 3 imma- 

 ture males and 2 immature females, all taken on Cocos Island, June 

 30, 1899. Measurements of the 2 adult males are given below. 



MEASUREMENTS, IN MILLIMETERS, OF CoCOmis rtdgZUayt. 



