black, or surf duck. 
215 
271 . ANAS PERSP1 C1LLA TAj LINNJEUS AND WILSON. 
BLACK, OB SURF DUCK. 
WILSON, PLATE LXV1I. FIG. I. 
This duck is peculiar to America, and altogether 
confined to the shores and hays of the sea, particularly 
where the waves roll over the sandy beach. Their food 
consists principally of those small bivalve shell fish 
already described, spout fish, and others that lie in the 
sand near its surface. For these they dive almost 
constantly, both in the sandy bays and amidst the 
tumbling surf. They seldom or never visit the salt 
marshes. They continue on our shores during the 
winter, and leave us early in May for their breeding 
places in the north. Their skins are remarkably strong, 
and their flesh coarse, tasting of fish. They are shy 
birds, not easily approached, and are common in winter 
along the whole coast from the river St Lawrence to 
Florida. 
The length of this species is twenty inches, extent 
thirty-two inches ; the bill is yellowish red, elevated at 
the base, and marked on the side of the upper mandible 
with a large square patch of black, preceded by another 
space of a pearl colour ; the part of the bill thus marked 
swells or projects considerably from the common surface ; 
tie nostrils are large and pervious ; the sides of the 
bid broadly serrated or toothed ; both mandibles are 
furnished with a nail at the extremity; irides, white, 
or very pale cream ; whole plumage, a shining black, 
marked on the crown and hindhead with two triangular 
spaces of pure white ; the plumage on both these spots 
is shorter and thinner than the rest; legs and feet, 
blood red ; membrane of the webbed feet, black ; the 
primary quills are of a deep dusky brown. 
Oi dissection the gullet was found to be gradually 
enlarged to the gizzard, which was altogether filled with 
brokm shell fish. There was a singular hard expansion 
at tin commencement of the windpipe, and another 
