KEY TO FAMILIES 



121 



Order V. Anseres. DUCKS, GEESE, and SWANS. 



Toes four; tarsus rounded not flattened as in the Grebes; tail well 

 developed; bill rounded and with tooth-like projections, or flattened 

 and with fluted ridges. Unlike the Grebes, most Ducks when pursued 

 fly rather than dive. 



1. Bill, long, narrow and rounded, with tooth-like projections (Fig, 



33). . . . Subfamily Mergina: MERGANSERS, p. 187. 



2. Bill more or less flattened and ducklike. 

 A. Lores feathered. 



a. True Ducks; tarsus shorter than the middle-toe without 

 nail; scales on its front transverse more or less square 

 (Fig. 34, a, 6). 



a 1 . Hind-toe without a flap or lobe (Fig. 34, a) .... Sub- 

 family Anatina: RIVER DUCKS, p. 190. 



a 2 . Hind-toe lobed (Fig. 34, 6). . . . Subfamily Fuligulina: 

 SEA and BAY DUCKS, p. 198. 



FIG. 34 



6. Tarsus generally longer than middle-toe, without nail; scales 

 on its front rounded. . . . Subfamily Anserince: GEESE, 

 p. 210. 

 B. Lores bare. . . . Subfamily Cygnince: SWANS, p. 215. 



