FAMILY ANATIDAS.— DUCKS, GEESE, AND SWANS. fia 
SUBFAMILY FULIGULINE. 
Bay and Sea Ducks. 
Ducks having flap or membraneous lobe on 
hind toe; tarsus, scutellate (transverse scales) in 
front. 
* Group |. Wing, from 5 to 6.50 inches long. 
Section 1. Tail feathers, not stiff and pointed. 
Head, greenish purple, with white patch (male); head, 
grayish brown with white patch (female or immature); no 
dark stripes on cheek; bill, less than three fourths inch wide. 
Charitonetta albeola, Buffle-head Duck. Dipper Duck. 
See No. 110. 
Charitonetta albeola. 
Section 2. Tail feathers, stiff and pointed. 
Throat, whitish; cheeks, white or whitish; bill, broad, three quarters inch or more wide. 
Erismatura jamaicensis. Ruddy Duck. 
See No. 
Front of head, including cheeks, black (adult); head with black stripes on side (female 
orimmature). Tropical species accidental in the United States. 
Nomonyx dominicus. Masked Duck. 
See No. 123. 
*Group 2. Wing, from 6.50 to 7.50 inches long. 
Section 1. Belly, white. 
Head, greenish purple, no white on head: back, barred 
black and white; speculum, white (male). 
Aythya afinis. Lesser Scaup Duck. Blue-=bill. 
See No. 106. 
Aythya affinis. 
Head, brownish, a patch of dull white at base of bill; no white on ear coverts; speculum, 
white (female). Aythya afinis. Lesser Scaup Duck. Blue-bill. 
See No. 106. 
* For directions for measurement, see page Y. 
