5H 



SNODGRASS AND HELLER 



The collection contains 5 specimens, being 3 adult females, i adult 

 male and 1 immature male, all taken July 3, 1S99, on Cocos Island. 



MEASUREMENTS, IN MILLIMETERS, OF Sula breiVStevi. 



(adult specimens.) 



SULA NESIOTES Heller and Snodgrass. 



Sula brewsteri Rothschild and Hartert, Novitates Zoologicae, vi, p. 179, 



1899 (11° 20^ N., 110° W.). 

 Sula 7iesiotes Heller and Snodgrass, The Condor, iii, No. 3, p. 75, May, 



1901 (Chpperton Island). 



Range. — Clipperton Island and adjacent waters. 



Adult Male. — Type of species Cat. No. 4271, Stanford University 

 Museum; from Clipperton Island, November 23, 1898. Upper 

 parts, excepting head and neck, light sooty-brovs^n, deepening on the 

 primaries into purplish-brown. Sides of chest and under wing 

 coverts, except an oblique white bar across middle coverts, brown 

 like the dorsum. Head above and on sides white with a yellowish 

 tinge, becoming ashy or light drab-gray below and posteriorly, grad- 

 ually shading into smoky-drab on chest and hind neck ; color of chest 

 ending abruptly against the white of the belly. The under parts pos- 

 terior to fore-breast and axillaries and an oblique bar across middle of 

 the under wing coverts white. Coloration of naked parts in life : bill 

 yellowish-green, becoming more greenish basally ; gular-sac dark pea- 

 green ; bare skin before eye purplish-violet; feet pea-green. 



Adult Fefnale. — Like the male in coloration except that the head 

 and neck are uniform with the back in color, and the feathers border- 

 ing the naked parts of the head are slightly grayer. Somewhat larger 

 in size than the male. 



This species is very similar to Sula brewsteri Goss, but the brown- 

 ish color of the head and upper parts is considerably paler, the bill is 

 green and the feet are green rather than yellowish. In size 6". nesiotes 

 averages somewhat larger than S. brewsteri. 



The collection contains four adult specimens, i inale and 3 female, 

 all taken at Clipperton in November, 1898. Their measurements are 

 as follows : 



