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. 
Fig. 33. 
1. Bill, long, narrow and rounded, with tooth-like projections (Fig. 
33). . . . Subfamily Mergince: 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, b). 
a 1 . Hind-toe without a flap or lobe (Fig. 34, a) . . . . Sub- 
family Anatince: River Ducks, p. 190. 
a 2 . Hind-toe lobed (Fig. 34, b). . . . Subfamily Fuligulince: 
Sea and Bay Ducks, p. 198. 
Fig. 34 
b . Tarsus generally longer than middle-toe, without nail; scales 
on its front rounded. . . . Subfamily Anserincs: Geese, 
p. 210. 
B. Lores bare. . . . Subfamily Cygnincs: Swans, p. 215. 
