84 NORTH AMERICAN BIRDS. 



ORDER ANSERES. THE LAMELLIROSTRAL 



SWIMMERS. (Page i.) 



Families. 



(Characters same as for the Order) Anatidae. (Page 84.) 



FAMILY ANATID.5L. THE DUCKS, GEESE, AND SWANS. (Page 84.) 

 Eggs numerous, always unmarked, with a hard and usually smooth shell. 



Genera. 

 a 1 . Neck shorter than body. 



b l . Tarsus shorter than middle toe, without claw. 



c 1 . Lower mandible without trace of lamellae along the side, but with a 

 series of distinct, tooth-like serrations along the upper edge. 

 (Subfamily Mergince.') 

 d l . Culmen longer than tarsus, and three times, or more, the depth of 



bill at base. 



e l . Serrations of both mandibles very conspicuously tooth-like, 

 and strongly inclined backward at tips. 



Merganser. (Page 88.) 

 e 3 . Serrations of both mandibles short, blunt, and not distinctly 



inclined backward at tips Lophodytes. (Page 89.) 



d*. Culmen shorter than tarsus Mergus. (Page 90.) 



e 2 . Lower mandible with a very distinct series of lamellae along the side, 



in addition to the series along upper edge. (Subfamily Anatince.) 

 d l . Lower portion of tarsus in front with a row of transverse scutellse. 

 e 1 . Lores entirely densely feathered ; wing less than 12.00. 

 f l . Tail normal. 



g 1 . Hind-toe without a distinct membraneous lobe. 

 A 1 . Bill not spatulate. 



z 1 . Tail-feathers narrow and pointed at tip. 



j 1 . Tail graduated for less than one-third its 

 total length, or else consisting of only 

 14 feathers, and culmen shorter than 

 middle toe without tarsus. 



Anas. (Page 90.) 



j*. Tail graduated for more than one-third 

 its total length, consisting of 16 



