166 SURF DUCK. 
Adult Female. Plate CCCXVII. Fig. 2. 
Bill greenish-black ; iris as in the male ; feet yellowish-orange, webs 
greyish-dusky, claws black. The general colour of the plumage is brown- 
ish-black ; darker on the top of the head, the back, wings, and tail ; 
on the breast and sides the feathers edged with dull greyish-white. 
Length to end of tail 19 inches, to end of wings 153, to end of claws 
18; extent of wings 31}; wing from flexure 83; tarsus 13; middle toe 
23, hind toe 7%. Weight 2 lb. 2 oz. 
In an adult Male, the tongue is 1 inch 9 twelfths long, has nume- 
rous conical papille at the base, is deeply grooved along the middle, 
has two lateral series of bristles, and terminates in a thin rounded lobe, 
2 twelfths long. On the middle line of the upper mandible are about 
ten short conical papillz, and on each of its margins about 35 lamelle ; 
on the lower an equal number. The heart is 1 inch 8 twelfths long, 
1 inch 2 twelfths broad. The cesophagus, 8} inches long, is wide, its 
diameter at the upper part being 1 inch, towards the middle of the 
neck 1 inch and a quarter. The proventriculus is 11 inch long ; its 
glandules cylindrical, 1} twelfths in length, and, as in all other ducks, 
arranged so as to form a complete belt. The stomach is a powerful 
gizzard of a roundish form, 1 inch 10 twelfths long, 1 inch 10 twelfths 
broad, its lateral muscles, very large, the right 10 twelfths thick, the 
left 9 twelfths. In the stomach were various small bivalve shells and 
much gravel. The cuticular lining longitudinally rugous; the grind- 
ing plates 3 inch indiameter. The intestine, 5 feet 7 inches in length, 
has an average diameter of 6 twelfths. The rectum is 7} inches long, 
8 twelfths in diameter. Of the cceca one is 3 inches 4 twelfths long, ey- 
lindrical, obtuse, 23 twelfths in diameter, the other 43 inches long. 
The aperture of the glottis is 8 twelfths long, with numerous minute 
papilla behind. The trachea presents the same structure as that of the 
Velvet Duck. Its upper rings, to the number of 9, are very narrow, 
and continuous with a large bony expansion, 7 twelfths long, and 8 
twelfths broad. Beyond this part its diameter is 5 twelfths, gradually 
diminishes to 3 twelfths about the middle, then enlarges to 5 twelfths. 
In this part the number of rings is 78. Then comes a roundish or 
transversely elliptical enlargement, 1 inch 2 twelfths in breadth, 9 
twelfths in length, convex before, slightly concave behind, and com- 
posed of about 12 united rings. The trachea then contracts to 4 twelfths 
