Order V
Anseres. - DUCKS, GEESE, and SWANS.
Toes four, the front ones fully webbed; tarsus not strikingly fiattened as in the Grebes; tail always well developed; bill with toothlike projections, fluted ridges, or gutters along its sides. 1. Bill very long, narrow, and rounded, with numerous toothlike projections along its sides. Subfamily Mergina: MERGANSERS (Fig. 16), p. 98. ... 3 2 FIG. 16. 2. Bill more or less flattened and ducklike.
A. Lores feathered. a. Tarsus shorter than the middle toe, without nail; scales on its front transverse, more or less square. ...
Subfamily Anatinæ; a1. Hind toe without a flap or lobe.
RIVER DUCKS (Fig. 17, a), p. 100. a2. Hind toe with a flap or lobe.
SEA and BAY DUCKS (Fig. 17, b), p. 107. ...
Subfamily Fuligulinæ; 2/3 a 23 b a FIG. 17. 23 b. Tarsus generally longer than the middle toe, without nail; scales on its front rounded... Subfamily Anserina: GEESE, P. 119. B. Lores bare. Subfamily Cygnina: SWANS, p. 124.
KEY TO FAMILIES.