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Bird-Lore 



corresponds to it. The transition to winter dress is less rapid, however, 

 than the abrupt change from winter to summer, and the parti-colored 

 plumage is most protective when the face of the country is partly 

 brown and partly powdered white by the snow - squalls that herald 

 the approach of winter. 



We have now followed the adult Ptarmigans in their molts through- 

 out the year, and will find that they differ from other members of the 



SEASONAL PLUMAGES OF PTARMIGAN 

 From specimens in the American Museum of Natural History. 

 a, summer. ^, postnuptial or autumn c, winter. 



Grouse family only in their more extensive prenuptial molt and in their 

 peculiar supplementary postnuptial molt. Let us now see what 

 happens to the young birds. The chicks hatching in July or earlier 

 are thickly covered with down. The juvenal plumage which follows 

 the down is not unlike the nuptial dress of the adults, but the wing 

 quills (except the two outer primaries, which are white) and the tail are 



