CATALOGUE OF CANADIAN BIRDS. 23 



Aythya vallisneria. 



CANVAS-BACK. 



Occurs throughout the Dominion, but is merely occasional in 

 the Maritime Provinces, while a common bird in Lake Manitoba 

 and the western portion of the Great Lakes. In the west it 

 ranges to Great Slave Lake and Alaska. 



Aythya marila nearctica. 



AMERICAN SCAUP DUCK. 



This species is fairly common throughout the Dominion, 

 breeding from about latitude 50 northward, though a few pairs 

 are said to nest on the St. Clair Flats, Ontario, in latitude 43. 



Aythya affinis. 



LESSER SCAUP DUCK. 



This species, which is better known to Canadian gunners as 

 the " Little Black-head," occurs throughout the Dominion, and is 

 abundant everywhere excepting in the Maritime Provinces, where 

 it is only " uncommon." It is not reported from Labrador, but 

 Dr. BELL found it " breeding in large numbers " on Nottingham 

 Island, in Hudson's Bay. It winters in the West Indies. 



Aythya collaris. 



RING-NECKED DUCK. 



According to Mr. THOMPSON'S list of Manitoba birds, this 

 species is abundant in the Red River Valley, and Mr. FANNIN 

 reports it abundant in British Columbia, but elsewhere in Canada 

 it appears to be of rather rare and irregular occurrence. It has 

 been taken as far north as Fort Simpson, and winters in the West 

 Indies. 



