344 Field Museum of Natural History — Zoology, Vol. IX. 



ward; winters from New Foundland to North Carolina and casually 

 to Florida; on the Pacific side from Aleutian Islands to California. 



Adult male: General plumage, entirely black; bill, black, the upper 

 mandible being yellowish orange at the base ; feathers on the bill more 



than one-half inch from, the nostril; 

 no white on the wing. 



Adult female: Brownish, or 

 sooty brown ; paler on the under 

 parts, becoming grayish white on 

 the belly; sides of the head, 

 whitish; feathers on the bill more 

 than one-half inch from -nostril; 

 no white on the wing. The 

 female is smaller than the male. 



Length, 19; wing, 9.10; tarsus, 1.65; bill, 1.80. 

 The American Scoter Duck is a common winter resident on Lake 

 Michigan, its numbers varying with different seasons. Arrives in 

 November and leaves early in April. 



Subgenus MELANITTA Boie. 

 64. Oidemia deglandi Bonap. 



White-winged Scoter. 

 Local nam.es: White-winged Coot. Velvet Duck. 

 Distr.: Northern North America, breeding from North Dakota and 

 Labrador north to Hudson Bay and the Arctic coast; winters from the 

 Gulf of St. Lawrence to South Carolina and casually to Florida, and 

 on the Pacific side from Alaska to Lower California. 



Adult male: General plumage, black; upper mandible, orange, 

 blackish at the base ; a white spot under the eye and a broad patch 



of white on the wing; 

 feathers on the bill less 

 than one-half inch from 

 the nostril. 



Adult female: Is gray- 

 ish brown, showing a 

 wash of grayish white 

 at the base of the bill 

 and behind the ears; the 

 speculum is white, which is a good distinguishing character. 



Length, 21; wing, 11.15; tarsus, 2; bill (culmen), 1.75; side 

 measure, 2.75. 



