THE CANVASS-BACK DUCK. 
147 
the former dusky at the tips ; tail, very short, pointed, con- 
sisting of fourteen feathers of a hoary brown ; vent and tail- 
coverts, black ; lining of the wing, white ; legs and feet, 
very pale ash, the latter three inches in width — a circum- 
stance which partly accounts for its great powers of swim- 
ming. 
The female is somewhat less than the male, and weighs 
two pounds and three-quarters; the crown is blackish- 
brown ; cheeks and throat, of a pale drab ; neck, dull 
brown ; breast, as far as the black extends on the male, 
dull brown, skirted in places with pale drab ; back, dusky 
white, crossed with fine waving lines; belly, of the same 
dull white, pencilled like the back; wings, feet, and bill, 
as in the male; tail-coverts, dusky; vent, white, waved 
with brown. 
The windpipe of the male has a large, flattish, concave 
labyrinth, the ridge of which is covered with a thin, trans- 
parent membrane ; where the trachea enters this, it is very 
narrow, but immediately above swells to three times that 
diameter. The intestines are wide, and measure five feet in 
length. 
