84 
BEFFEL-HEADED DECK. 
speck of the same on the lower eyelid. Six of the secondary quills white 
on the outer web. Lower parts white, shaded into light greyish-brown on 
the sides ; tail dull greyish-brown. 
Length to end of tail 13 inches, to end of claws 13i, to end of wings 11 \ ; 
extent of wings 22i. Weight 8 oz. 
Individuals of both sexes differ much in size, and in the tints of their 
plumage. 
In an adult male, the tongue is 1 inch and 2 twelfths long, fleshy, and of 
the same general form as in the other Ducks already described. The oeso- 
phagus is 63 inches long, passes along the right side, has a diameter at the 
top of 4 i twelfths', enlarges about the middle to 9 twelfths, and contracts to 
\ inch as it enters the thorax. The proventriculus is 1 inch long, 8 twelfths 
in its greatest diameter, its glandules, which are of moderate size, forming a 
complete belt, as in all other Ducks. The stomach is a muscular gizzard of 
a roundish form, 1 inch 5 twelfths long, 1’ inch 4 twelfths in breadth ; its 
lateral muscles 5 twelfths in thickness ; its epithelium tough, hard, and 
slightly rugous. The intestine is 3 feet 11 inches long ; its average diameter 
3 twelfths, its walls thick, and its inner surface villous. The rectum is 3 
inches long ; the coeca 2 % inches in length, their diameter at the commence- 
ment 1 twelfth, towards the end 2 twelfths. 
The trachea is 5 inches long, much flattened, its rings unossified, its 
diameter at the top 23 twelfths, towards the lower part 3 twelfths, having 
scarcely any appearance of dilatation at the part which is so excessively 
enlarged in the Golden-eyed Duck, which in form and habits is yet very 
closely allied. The lateral muscles are strong, and there are cleido-tracheal 
and sterno-tracheal muscles, as in other Ducks. 
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