140 
THE CANVASS-BACK DUCK. 
close-set, zigzag lines, on a pale ground, more or less shaded 
off with ash,” — a description much more applicable to the 
red-head, which, very probably, is the species meant. 
In the figure of the pochard given by Mr. Bewick, who 
is generally correct, the bill agrees very well with that of 
our red-head ; but is scarcely half the size and thickness 
of that of the Canvass-Back ; and the figure in the Planches 
Enluminees corresponds, in that respect, with Bewick's. 
In short, either these writers are egregiously erroneous in 
their figures and descriptions, or the present Duck was 
altogether unknown to them. Considering the latter sup- 
position the more probable of the two, I have designated 
this as a new species, and shall proceed to detail some par- 
ticulars of its history. 
The Canvass-Back Duck arrives in the United States 
from the north about the middle of October ; a few descend 
to the Hudson and Delaware, but the great body of these 
birds resort to the numerous rivers belonging to and in the 
neighbourhood of the Chesapeake Bay, particularly the Sus- 
quehanna, the Patapsco, Potomac, and James rivers, which 
appear to be their general winter rendezvous. Beyond this, 
to the south, I can find no certain accounts of them. At 
the Susquehanna, they are called Canvass-Backs ; on the 
Potomac, White-Backs; and on James river, Sheldrakes. 
They are seldom found at a great distance up any of 
these rivers, or even in the salt-water bay; but in that 
particular part of tide water where a certain grass-like plant 
