SPECIES 18. ANAS 



CANVAS-BACK DUCK. 



[Plate LXX. Fig. 5.] 

 PBALE'S Museum, JVo. 2816. 



THIS celebrated American species, as far as can be judged 

 from the best figures and descriptions of foreign birds, is alto- 

 gether unknown in Europe. It approaches nearest to the Pochard 

 of England, Anas ferina, but differs from that bird in being 

 superior in size and weight, in the greater magnitude of its bill, 

 and the general whiteness of its plumage. A short comparison 

 of the two will elucidate this point. The Canvas-back measures 

 two feet in length, by three feet in extent, and when in the best 

 order weighs three pounds and upwards. The Pochard, accord- 

 ing to Latham and Bewick, measures nineteen inches in length, 

 and thirty in extent, and weighs one pound twelve or thirteen 

 ounces. The latter writer says of the Pochard, "the plumage 

 above and below is wholly covered with prettily freckled slen- 

 der dusky threads disposed transversely in close set zig-zag lines, 

 on a pale ground, more or less shaded off with ash;" a descrip- 

 tion much more applicable to the bird figured beside it, the Red 

 Head, and 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 Canvas- 

 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 supposition the more probable of the two, I have desig- 

 nated this as a new species, and shall proceed to detail some 

 particulars of its history. 



