44 



KEY TO FAMILIES. 



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



Toes four, the front ones fully webbed ; tnrsu.s not strikingly flattened as 

 in the Grebes; tail always well developed; bill with toothliko 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 Mergina : MERGANSERS (Fig. 

 16), p. 98. 



Fio. 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 1 . Hind toe without a flap or lobe. . . . Subfamily Anatina: 



RIVER DUCKS (Fig. 17, a), p. 100. 



a*. Hind toe with a flap or lobe. . . . Subfamily Fuligulina; 

 SKA and BAT DCCKS (Fig. 17, b), p. 107. 



Fio. 17. . 



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



on its* front roundi-il. . . . Subfamily Anserince: GEESE, p. ll'J. 

 2?. Lores bare. . . . Subfamily Cygnince. : SWANS, p. 124. 



