CANVAS-BACK, a widely distributed fresh-water duck (Aythya vallisneria), much sought as a table luxury, as its flesh is con sidered superior to that of all other ducks. It is about 22 inches in length and its reddish chestnut head and neck are much shaded with dusky hues; the lower neck, breast and fore part of the back, with the rump and tail-coverts, are black; and the back and sides gray, covered with fine lines and dots, so that the plumage re sembles canvas. By reason of its similarity, this duck is frequently confounded with the red-head (q.v.). "The canvas-back is larger, its head darker, and its bill a deep black, while that of the red-head is deep blue, or a slatish color. The shape of the bill of the canvas back is wedged and long; of the red-head moderately long and concave. . . . They are very tenacious of life, their bump of stubborn ness being fully developed, and they will dive long distances, and prefer death by any other means than human agency. When one is crippled it will usually look around for an in stant, to see where the danger lies, then down it goes, and if rushes or cover are near, it is good-bye to that duck,—it will not be seen again. When one is crippled it should be shot
again, and at once." The food of the canvas back consists chiefly of the roots of wild celery (Zostera vallisneria), which resembles the cul tivated celery in appearance. It grows densely in the shallow parts of the Chesapeake Bay and Susquehanna River about the Great Lakes and in the Mississippi Valley. Few canvas-backs are found east of the Hudson and Delaware rivers. It is almost safe to say that where the plant grows in abundance, the canvas-back is almost sure likewise to be found; consequently the peculiarly delicate flavor of its flesh, and the market value of this duck, increase with the amount of celery it consumes, as otherwise it is hardly distinguishable from the red-head in flavor. The canvas-back breeds north of Dakota, building its nest on the ground, in a marsh, and laying from 6 to 10 greenish-buff eggs. Consult Elliot, (Wild Fowl of North America' ; Job, (Among the Wild Fowl.'