44 



KEY TO FAMILIES. 



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



Toes Tour, 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 Merging : MERGAN&ERS (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 ite 

 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 Fuligulince; 

 SEA and BAY DUCKS (Fig. 17, b), p. 107. 



FIG. 17. 



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



on its front rounded. . . . Subfamily Antenna: GEESE, p. 119. 

 . Lorea bare. . . . Subfamily Cygninat: SWANS, p. 124. 



