102 AYTHYA. POCHAllD, 



semicircular. OEsophagiis rather wide ; proventriculus oblong. 

 Stomach a very muscular gizzard, of a transversely elliptical 

 form, placed obliquely, with longitudinally rugous epithe- 

 lium, forming thick, somewhat concave circular grinding 

 plates. Intestine very long and w4de ; coeca long, of mode- 

 i-ate Avidth ; rectum very short. 



Nostrils small, in the lower and fore part of the nasal 

 sinus ; eyes small ; ears very small. Legs very short, placed 

 rather far behind ; tarsus compressed, with small anterior 

 scutella ; hind toe very slender, with a narrow membrane ; 

 outer toes about equal, and double the length of the tarsus ; 

 interdigital membranes emarginate ; claws small, slender, 

 little arched, rather pointed. 



Plumage dense, firm, glossy ; feathers of the head and 

 neck very soft, blended, silky or velvety ; of the other parts 

 moderate, ovate. Wings short, convex, narrow, pointed, of 

 twenty-six quills ; primaries narrow, the first longest. Tail 

 very small, much rounded, of fourteen stiffish, tapering 

 feathers. 



Brown, grey, white, and brownish-red are the prevailing 

 colours of the plumage. The females have the colours less 

 decided, brown being substituted on the upper parts and 

 sides, and the m.arkings larger. The young resemble the 

 females. This genus is one of those which approach nearest 

 to the Anatinse, and the species are by no means exclusively 

 marine, although in Avinter they frequent estuaries, and even 

 the open shores, feeding chiefly on the rhizomata of Valis- 

 neria, Zostera, and other plants. In summer they reside 

 chiefly in fresh-water marshes and lakes, where they breed, 

 and feed on larva?, insects, and mollusca. They are not 

 expert at walking, but swim and dive with great ease, and 

 have a rapid, direct flight. When fed on vegetable sub- 

 stances they afibrd good eating, the flesh of one species, 

 Aythya Valisneriana, being in America celebrated above that 

 of every other Duck, although it is very probably in no 

 degree diflerent from that of Aythya Ferina, which, although 

 well-flavoured, is not, I think, to be compared with that of 

 Anas Boschas, or any of the Teals. Three species occur in 

 Britain. 



