72 KEY TO THE BIRDS OF EASTERN NORTH AMERICA. 



Head, greenisli purple, no white on head; l)ack, dull l)lack; speculum, gray (male). 



Aiithya collarls. Ring=neck Duck. 

 See No. 107. 

 Head, dull l)ro\vn, hrowui-h white at base of bill and lielow eye; speculum, gray 

 (female). Aytlvjn coJhiris. Ring=neck Duck. 



See No. 107. 

 Head, greenish purple, a large patch of white on back of head (male). 



GharltonHln alhcola. Buffle^headed Duck. 

 See No. 110. 

 Head, dark brown or dusky, a patch of white behind the eye (on ear coverts) ; no 

 white or brownish white at base of bill; speculum, white (female). 



CharitoneMa alhoola. Buffle^^headed Duck. 

 See No. 110. 



Section 2. Belly, not white. 



Plumage, variously marked with white, slate-color, and chestnut (male). 



Histrionints histrioninis. Harlequin Duck. 

 See No. 112. 

 General plumage, dull brown, mottled on the under parts (female). 



Histrionkus histrionicvs. Harlequin Duck. 

 See No. 112. 

 Head, mostly white, greenish on lores and occiput (male). 



Eniconi-ttn steUeri. Stellers' Duck. 

 See No. 114. 

 Head, light brown; belly, clear, soot}' brown (female). 



Eniconetta stelleri. Stellers' Duck. 

 See No. 114. 



* Group 3. Wing, from 7.50 to 8.50 inches long. 



Section 1. Head, marked with more or less white or 

 brownish white; belly, white, sometimes tinged with 

 dusky or gray on lower part. 



Head, brownish ; a patch of dull white on face at base 

 of bill; speculum, white (female). 



Aiithijd iniirila. Greater Scaup Duck. Blue=bill. 



See No. 105. 



Aytliya marila nearctica. • 

 Speculum, v^hlte, similar to preceding l>ut somewhat smaller (female). More common in 

 the South than the Greater Scaup Duck. At/thyn atUnis. Lesser Scaup Duck. 



See No. 106. 



For directions for measurement, see page 0. 



