BUFFEL-HEADED DUCK. 373 



speck of the same on the lower ej'elid. 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 13 J, to end of wings 11 J; 

 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 6f inches long, passes along the right side, has a diameter at the 

 top of 4^ 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 cceca 2i 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 2\ 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. 



