i6o 



KEY TO THE WATER BIRDS OF FLORIDA. 



Aythya vallisneria. 



Aythya afSnis. 



Length, 21; Wing, S.40 ; Tarsus, 1.60; Bill, 2.20. 

 Head rufous brown; speculum grayish ; upper 

 feathers edged witli black ; the rest narrowly 

 tipped with white. (See figure showing difference 

 in bill from Canvas-back.) 



Length, 20.50; Wing, 8.30; Tarsus, 1.60; Bill, 2.20. 

 Head grayish brown ; speculum grayish ; upper 

 feathers edged with l^lack ; the rest narrowly 

 tipped with white. Closely resembles female of 

 Ring-neck Duck (A. collaris), but is larger. 



Length, 19; Wing, 8.50: Tarsus, 1.50; Bill, 2. Head 

 black glossed with green ; back grayish ; specu- 

 lum white. 



Length, 17; Wing, 8.10; Tarsus, 1.50: Bill, i.So. 

 Similar to the preceding species, from which it 

 differs only in being somewhat smaller ; head black 

 with purplish gloss; speculum white. 



Aythya americana (male). 

 Redhead Duclc. See page 226 



Aythya americana (female). 

 Redhead Duck. See page 226 



Aythya marila nearctica (male). 

 Greater Scaup Duck. 

 Bluebill. See page 228 



Aythya affinis (male). 

 Lesser Scaup Duck. 

 Bluebill. See page 229 



