OANVASS-BACK DUCK. 
19 
superior to that of the Pochard or Red-head, which often mingles in the 
same flocks ; and both species are very frequently promiscuously sold in the 
markets as Canvass-backs. 
In the plate are represented two Males and a Female. In the back ground 
is a view of Baltimore, which I have had great pleasure in introducing, on 
account of the hospitality which I have there experienced, and the generosity 
of its inhabitants, who, on the occasion of a quantity of my plates having 
been destroyed by the mob during an outburst of political feeling, indem- 
nified me for the loss. 
Canvass-backed Duck, Anas valisneria , Wils. Amer. Orn., vol. viii. p. 103. 
Fuligula valisneria, Bonap. Syn., p. 392. 
Fuligula valisneria, Canvass-backed Buck , Swains, and Rich. F. Bor. Amer., vol 
ii. p. 450. 
Canvass-backed Duck, Nutt. Man., vol. ii. p. 430. 
Canvass-backed Duck, Fuligula valisneriana, Aud. Orn. Biog., vol. iv. p. 1. 
. « 
Male, 22, 33. Female, 2(H, 301. 
Abundant during winter from the mouth of the Delaware to New Orleans, 
in all the estuaries. Columbia river. Breeds on the Rocky Mountains and 
northward. 
Adult Male. 
Bill as long as the head, deeper than broad at the base, the margins 
parallel, slightly dilated towards the end, which is rounded, the frontal 
angles rather narrow and pointed. Upper mandible with the dorsal line at 
first straight and declinate, then slightly concave, direct for a short space 
near the tip, where it is incurved, the ridge broad and concave at the base, 
narrowed at the middle, enlarged and convex at the end, the sides nearly 
erect and concave at the base, becoming anteriorly more and more declinate 
and convex, the edges curved upwards, with about 50 lamellse, the unguis 
small and oblong. Nostrils sub-medial, linear-oblong, rather large, pervious, 
near the ridge, in an oblong depression covered with soft membrane. Lower 
mandible flattened, being but slightly convex, with the angle very long and 
rather narrow, the dopsal line very short and straight, the erect edges with 
about 55 inferior and 105 superior lamellse, the unguis obovato-elliptical. 
Head rather large, compressed, convex above. Eyes small. Neck of 
moderate length, rather thick. Body full, depressed. Wings small. Feet 
very short, strong, placed rather far behind ; tarsus very short, compressed, 
anteriorly with narrow scutella continuous with those of the middle toe, and 
having another series commencing half-way down and continuous with those 
of the outer toe, the rest reticulated with angular scales. Hind toe small, 
with an inner expanded margin or web ; middle toe nearly double the length 
