MERGANSERIN^. 193 



the Mergansers, although few in number, seem yet to 

 form a very distinct family, of which the following are 

 among the most important characters : The body is 

 large, elongated, elliptical, and depressed ; the neck long 

 and slender ; the head oblong, compressed, anteriorly 

 narrowed. Bill rather long, straight, or a little rearcuate, 

 slender, tapering, and toward the end becoming nearly 

 cylindrical ; the edges of both mandibles furnished with 

 lamellae much narrower than in the Ducks, and in the 

 larger species conical, acuminate, and directed backward ; 

 the unguis oblong, of the same breadth as the mandibles, 

 and the upper abruptly decurved. Mouth rather narrow, 

 but dilatable ; tongue fleshy, with lateral bristles, and lace- 

 rated tip ; oesophagus very wide ; stomach rather small, 

 roundish, very muscular, with thick, rugous epithelium ; 

 intestine long, rather wide, with moderately large coeca, 

 and globular cloaca. Trachea variously enlarged, and 

 always having an enormous dilatation at its lower extre- 

 mity, partly bony and partly membranous ; bronchi wide. 

 Eyes rather small. Nostrils oblong, submedial. Ear- 

 aperture very small. Legs short, placed far behind ; tarsi 

 very short, much compressed ; toes four ; the first very 

 small, elevated, arcuate, with a lobiform membrane ; an- 

 terior toes long, with full membranes, the inner with a 

 bilobate web ; claws small, little arched, compressed. 

 Plumage moderately full, firm, glossy ; the feathers curv- 

 ed, with a small down-plumule ; head and nape crested ; 

 wings short, of moderate breadth, convex, pointed, the 

 first quill longest ; tail short, much rounded, of from 

 fourteen to eighteen, stiffish, tapering feathers. 



The males, which are larger than the females, assume 

 in summer somewhat of their appearance. As in the 

 Anatinse, there is a speculum on the wing. Their food 

 consists chiefly of fish, for which they dive ; their flight 

 is quick, and direct ; but they walk with difficulty. They 

 pass the summer in the colder regions, form a bulky nest, 



