Notes on the Plumage of North American Sparrows 



19 



October, January, March and June specimens show how the change in color 

 from brown to black is produced. 



The female (Fig. 3) passes through the same series of changes as the male, 

 but does not become so pronouncedly black and white, in part because her 

 feathers are basally not not so purely black and white and in part because 

 they do not wholly lose the brownish (now faded to grayish) tips of the win- 

 ter plumage. The breeding female is apparently more protectively colored 

 than the male, though the differences between their plumages are due to an 

 external mechanical cause rather than to an internal physiological one. 



Plectrophenax hyperboreus (Fig. i). This beautiful species, during the 

 breeding season, is found only on Hall and St. Matthew islands in Bering 

 Sea, migrating in numbers to the coast of Alaska. 



I have not sufficient material to describe its plumage changes which, 

 however, are probably not unlike those of the common Snow Bunting. 



CARDINAL AND GROUND DOVES 

 Photographed by George Shiras, 3d., at Ormond, Fla. 



