JAN., 1909. BIRDS OF ILLINOIS AND WISCONSIN CORY. 



333 



with feathers and down. The eggs are cream white or grayish white, 

 and measure about 2.35 x 1.40 inches. 



52. Marila vallisneria (WiLS.). 

 CANVAS-BACK DUCK. 



Ay thy a vallisneria (Wils.), A. O. U. Check List, 1895, p. 53. 

 Distr.: North America, breeding chiefly from North Dakota, 

 Alberta, and southern Canada, and northwest to Alaska, migrating 

 south in winter to the southern and southeastern United States from 

 Chesapeake Bay and the Carolinas along the Gulf coast to Texas and 

 Mexico; accidental in Cuba. 



Adult male: Head and neck, rufous brown, becoming dusky on 

 the crown and chin; the breast and upper portion of the back, 



blackish; rest of upper parts 

 and wing coverts showing fine, 

 wavy lines of black, general 

 appearance being grayish; 

 belly, white, the lower portion, 

 faintly lined with dusky; 

 sides, white, showing the 

 delicate lines as on the back, 

 but very much fainter and 

 sometimes wanting. 



Adult female- Head and 

 neck, cinnamon brown, paler 

 on the throat; belly, white or grayish white. 



Length, 20 to 22; wing, 8.75 to 9.25; bill, .75 to .80; tarsus, 1.70. 

 The peculiar form of the bill will always distinguish the Canvas- 

 back from the Redhead, which is the only species with which it could 

 be confounded. This species is still common during the migrations 

 in both Illinois and Wisconsin. Although it may have formerly 

 bred occasionally in Wisconsin, it is doubtful if it does so at the 

 present time. Messrs. Kumlien and Hollister write: "We know of 

 three instances of females being seen with nestlings but incliite to 

 the opinion that the birds were winged and could not continue the 

 journey northward." (Birds of Wisconsin, 1903, p. 22.) 



53. Marila marila (LiNN.). 

 SCAUP DUCK. 



Aythya marila nearctica Stejn., A. O. U. Check List, 1895, P- 53- 

 Local names: Bluebill or Blackhead. 



