INDEX TO KEY. 



Family ANATID^. Ducks, Geese, and 



Swans. 

 Subfamily MERGINiE. Mergansers. 



Fish-eating Ducks having narrow bills with tooth-like serrations on edges ; 

 tarsus, scutellate (transverse scales) in front. 



Group 1. Wing, 6.50 to 8.50 inches long .... See page 56. 

 Group 2. Wing, 8.50 to 12 inches long . . . . . " " 57. 



Subfamily ANATINi^. River and Pond Ducks. 



Ducks having hind toe without well developed membraneous lobe or flap ; 

 tarsus, scutellate (transverse scales) in front. 



Group 1. Wing, 5 to 7.50 inches long ..... See page 58. 



Group 2. Wing, 8 to 10 inchfes long . . . . . " " 59. 



Section 1. Belly, white . . . . . . . " " 59. 



Section 2. Belly, not white . . . . . . " " 59- 



Group 3. Wing, 10 to 14 inches long . . . . . " " 60. 



Section 1. Belly, white, or tinged with dusky or gray on 



lower part .... ...."" 60. 



Section 2. Belly, not white . . . ■ . . . " " 61. 



Subfamily FULIGULINiE. Bay and Sea Ducks. 



Ducks having a flap or membraneous lobe on hind toe; tarsus, scutellate 

 (transverse scales) in front. 



Group 1. Wing, 5 to 6.50 inches long ..... See page 62 



Section 1. Tail feathers, not stiff and pointed . . . " " 62 



Section 2. Tail feathers, stiff and pointed . . . " " 62 



Group 2. Wing, 6. 50 to 7 . 50 inches long . . . . " " 63 



Section 1. Belly, white . . . . . . " " 63 



Section 2. Belly, not white . . . . . . " " 64 



Group 3. Wing, 7.50 to 8.50 inches long . . . . " " 64 



Section 1. Head, with more or less white or brownish white; belly, white, 



sometimes tinged with dusky or gray on lower part . See page 64 

 Section 2. No white or grayish white on head ; belly, white, sometimes 



tinged with grayish white on head .... See page 65 



Section 3. Belly, not white . . . . . . " " 65 



54 



