44 



KEY TO FAMILIES. 



Order V. Anseres* — Ducks, Geese, and Swans. 



Toes four, the front ones fully webbed ; tarsus not strikingly flattened as 

 in the Grebes; tail always well developed; bill with toothlike projec- 

 tions, fluted ridges, or gutters along its sides. 



1. Bill very long, narrow, and rounded, with numerous toothlike pro- 

 jections along its sides. . . . Subfamily Mergince : Mergansers (Fig. 

 16), p. 98. 



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. 

 a^. Hind toe without a flap or lobe. . . . Subfamily Anatince; 



EivER Ducks (Fig. 17, a), p. 100. 

 a". Hind toe with a flap or lobe. . , . Subfamily FuligulincB^ 

 Sea and Bay Ducks (Fig. 17, h)^ p. 107. 



Fig. 17. 



h. Tarsus generally longer than the middle toe, without nail ; scales 

 on its front rounded. . . . Subfamily Avserince : Geese, p. 119. 

 B. Lores bare. . . . Subfamily Cygninoe : Swans, p. 124. 



