U. S. NATIONAL MUSEUM 



BULLETIN 162 PLATE 39 



Willow-ptarmigan Chick 

 Yukon Delta, Alaska, Juno 23, 1914. 



Female Willow ptarmigan on Nest 



Yukon Delta, Alaska, June 16, 1914. Both photographed by F. Seymour Hersey for the author. 



