1926] Swarth: Birds and Mammals from the Atlin Region 77 



newly hatched bird grows a set of small-sized wing feathers to accord 

 with the tiny wing, and these are molted and replaced with others of 

 the same juvenal type but of larger size. This can be demonstrated 

 by measurement of corresponding feathers upon the wings of young 

 birds of different ages. 



Fig. C. Tails of Vendragapus ohscurus richardsonii, showing variation due to 

 age; % natural size, a, immature male, during first year (M.V.Z. no. 4:264:2) ; 

 h, adult male, in second year or older (M.V.Z. no. 533). 



First winter plumage (male) : The sexes are unlike at this stage, 

 nearly as much so as in the fully mature birds. The post- juvenal molt 

 begins late in July or early in August, inaugurated by the shedding 



