ZOOLOGY. 121 



The Mergansers form their nests on the ground, which they 

 line with down from their breasts, both sexes contributing 

 towards the composing of the structure ; this down is much 

 sought after by the natives of those countries where these 

 birds resort, and is of equal value with the down of the Eider 

 Duck. Several species migrate to this country during 

 winter. British Ornithology, vols. 2^ 3. 



13. jdnas. Duck. J?27/ broad, depressed, the tip furnished 

 with a horny appendage oi nail ; the edges of the bill 

 pectinated ; nostrils small, oval ; tongue broad, fringed 

 near the base ; front toes webbed ; hind one seperate. 



This genus is divided into Ducks, which have their bills 

 depressed; Geese, having their bills compressed; and 

 Swans, which are of larger size, having compressed bills, 

 generally furnished with a hard gibbosity at the base. 



Many of this class contribute largely to the support and 

 convenience of mankind. They all reside in the immediate 

 vicinity of wafer, from whence they derive the principal part 

 of their food ; some are entirely marine, and feed on fish. 

 moluscse, and shell-fish, the flesh of these is no better than 

 carrion, but their down and feathers are articles of com- 

 merce; other kinds are commonly found in rivers, lakes, and 

 extensive meres, feeding on aquatic insects, small reptiles, 

 worms, seeds and grain, the flesh of these is of good flavour, 

 and is in general request for the purposes of food ; their 

 quills, feathers, and down, are likewise articles of commerce. 

 Numerous species of the latter kinds are kept in a domestic 

 state : they are all very shy, of a suspicious nature, and 



