AMERICAN SCOTER DUCK. 119 



Boston, who is quite competent to the task, has been equally unsuc- 

 cessful, although in the course of the last two years he has examined a 

 great nimiber of individuals. 



OiDEMiA Americana, Swainson. American Scoter, Richards, and Swains. Fauna 



Bor.- Americana, vol. ii. p. 450. 

 American Scoter Duck, NuttaU, Manual, vol. ii. p. 422. 



Adult Male. Plate CCCCVIII. Fig. 1. 



Bill a little shorter than the head, very broad, higher than broad at 

 the base, much depressed toward the end, which is semi-elliptical. Upper 

 mandible with the dorsal outline convex at the base, descending and con- 

 cave in the middle, again convex toward the end ;' the basal part tumid 

 with a median groove, the ridge broad and slightly convex between the 

 nostrils, the sides at first nearly erect and concave, gradually becoming 

 more depressed and convex, the sides soft, internally lamellate, nearly 

 parallel for half their length, dilating a little to beyond the nostrils, 

 then contracting ; the unguis very large, broadly elliptical. Lower 

 mandible flattened, with the angle long and rather narrow, the dorsal 

 line slightly convex, the edges parallel, the tip rounded, the unguis 

 very broadly elliptical. Nostrils medial, elliptical, pervious, near the 

 ridge. 



Head large, oblong, compressed, rounded above. Eyes of moderate 

 size. Neck short and thick. Body large and much depressed. Feet 

 very short, placed rather far behind ; tarsus very short, much compres- 

 sed, having anteriorly in its whole length a series of small scutella and 

 above the outer toe a partial series, the rest covered with reticular an- 

 gular scales. Hind toe small, with a free membrane beneath ; anterior 

 toes nearly double the length of the tarsus, connected by reticulated 

 membranes having a sinus on their free margins, the inner with a lobed 

 marginal membrane, the outer with a thiclt margin, the third and fourth 

 about equal and longest. Claws small, that of the first toe very small 

 and curved, of the middle toe largest, with a dilated inner edge, of the 

 rest slender, all rather obtuse. 



Plumage soft, dense, blended, slightly glossed. Feathers on the 

 head and neck of a velvety texture, being very small, oblong, with the 

 terminal filaments disunited. Wings rather short, narrow, and pointed ; 

 primary quills curved, strong, tapering, pointed, the first with the in- 



