178 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



Upper parts : Mantle and wings pearl grey. The primary quills dusky, 

 on their exposed surface, heavily frosted with pearl grey, which becomes 

 less obvious with the seasonal wear. On the first primary the white of 

 the inner web extends to within about two and a half inches of the tip 

 and cuts a distinct color wedge into the dusky portion of the web. This 

 is also indicated on the second primary and less plainly on the third ; it 

 gradually becomes obsolete on the others. Shafts of the first six primaries 

 ivory white. This character varies in individuals, some showing it only 

 on the first four quills. 



Tail : Pearly grey like the rest of the upper parts but lighter in shade ; 

 the outer feathers incline strongly to whitish. 



Lower parts : Ivory white, which color extends on the sides of the face 

 to the lower edge of the eyes and also occupies the lower third of the 

 loral region. 



Bill: Black (sometimes reddish at the base). 



Iris : Dark hazel brown. 



Tarsi and Feet : Black, often with a reddish tinge on the toes and webs. 



Adult female, like the male in color but smaller and with a somewhat 

 more slender bill. 



Adttltsin Winter. — Like the breeding plumage, but lacking the black on 

 the head. The region occupied by the cap is streaked rather obscurely with 

 dusky; about the eye, extending from the loral region to the auriculars, 

 this streaking is concentrated forming a more or less well defined patch. 

 (Adult female P. U. O. C. 4248, Cobbs Island, Virginia, 8 September, 

 1881, W. E. D. S.) 



An adult male, 4246 P. U. O. C, taken at the same locality on the 

 same day has the cap half moulted, but still clearly defined, mottled with 

 white. 



Young birds of the year are similar in appearance to winter adults, but 

 the streaking on the head is greyer and less well defined, the ground color 

 of the head being white with a decided buff tint. The back at this time 

 is pale buffy white and pearl intermixed. (Female of the year 4243, P. 

 U. O. C. Cobbs Island, Virginia, 8 September, 1881, W. E. D. S.) 



A half grown male bird (4197, P. U. O. C. Cobbs Island, Virginia, 29 

 August, 1 88 1, W. E. D. S.), has many buffy fawn colored feathers, barred 

 with dusky on the mantle, the tertials and some of the scapulars are for 

 the most part pearl grey, but each feather is tipped broadly with buffy 



