160 BIRDS OF ILLINOIS. 



Total length, about 20.00 to 22.00 inches ; extent, 30.00 to 33.00; wing, 8.75-9.25; culmen, 

 2.10-2.50; greatest width of bill, .75-80; tarsus, 1.70; middle toe, 2.60-2.65. 



Many persons experience difficulty in distinguishing; the Can- 

 vas-back from the Red-head. An examination of the bill alone, 

 however, is sufficient to distinguish them with absolute cer- 

 tainty, this member being radically distinct in shape in the two 

 birds, as shown by the diagnostic character of the subgenera 

 which they respectively represent, on page 156. The plum- 

 "age of the adult males, while somewhat similar, will be seen 

 on comparison to be really quite different. The Canvas-back 

 has the front part of the head dusky, or blackish, the rest of 

 the head, with the whole neck, being rusty chestnut. The Red- 

 head, on the other hand, has the u'li<>/< head, and only the 

 upper half of the neck, a much brighter reddish chestnut, with 

 purple gloss. The back and scapulars are much whiter in the 

 Canvas-back, and this species has a wholly blackish bill and 

 red eyes, while the Red-head has a leaden-blue, black-tipped bill 

 and yellow eyes. 



The famous Canvas-back, so higly prized by eastern epicures, 

 is an abundant migrant in Illinois, as indeed it is entirely across 

 the continent. It breeds from Minnesota northward, and winters 

 in the Southern States, chiefly along the South Atlantic and 

 Gulf coasts, though it has been known to occur in mild winters 

 in the southern part of Illinois. 



Whatever the cause may be, the opinion held as to the edi- 

 ble qualities of this species varies greatly in different parts of 

 the country. Nowhere has it so high a reputation as in the 

 vicinity of Chesapeake Bay, where the alleged superior quality 

 of its flesh is ascribed to the circumstance that it there feeds 

 chiefly on the " water celery " (Vallisneria, spiralis) . That this 

 supposed explanation is wholly fallacious, however, is evident 

 from the fact that the same plant grows in far greater abund- 

 ance in the upper Mississippi Valley, where, also, the Canvas- 

 back feeds on it. Hence it is highly probable that fashion and 

 imagination, or perhaps a superior style of cooking and serving, 

 play a very important part in the case. 



In California, however, where the Vall'/xm r'm does not grow, 

 the Canvas-back is considered a very inferior bird for the table. 



