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



General plumage, brown; top of head and wings, dark; a spot of 

 dull white at base of bill and behind eye; no white on wings (female). 



Oidemia perspicillata. 

 Surf Scoter. Skunk-head Coot. 

 See No. 65. 



SECTION 4. Hind toe, with well defined membraneous lobe or flap; 

 belly, not white; no white on head. 



Axillars, brown; secondaries, white, forming a white wing patch; 

 upper parts dark brown; under parts, sometimes brown, sometimes 

 grayish (female ) . Oidemia deglandi. 



White-winged Scoter. White-winged Coot. 



See No. 64. 



* GROUP 5. Wing, 10 to 14 inches long. 



SECTION 1. Hind toe, with well defined membraneous lobe or flap; 

 head, with more or less white, or grayish white; belly, black. 



General plumage, black ; speculum, white ; spot under eye, white ; 

 axillars, black; bill, orange at base (male). Oidemia deglandi. 



White-winged Scoter. White-winged Coot. 



See No. 64. 



General plumage, black ; head, black, with patch of white on 

 crown and nape; no white on wing; axillars, black; bill, orange, 

 black, and white (male). Oidemia perspicillata. 



Surf Scoter. Skunk-head Coot. 



See No. 65. 



American Eider Duck. 

 Somateria dresseri. 



Northern Eider Duck. 

 Somateria mollissima borealis. 



* For directions for measurement, see page 21. 



