The Willow Ptarmigan 239 



last tracts affected ; so that by the middle of October some will be seen 

 with dark feathers still predominating in the head and back. This, of 

 course, gives much the same effect as at an early stage of the spring molt. 



The Willow Ptarmigan selects the site for its nest during the third 

 week of May, and by the second week of June sets of eggs are usually 

 complete. The nest is a slight depression in the moss 

 on the open ground ; usually the summit of a hum- 

 mock is selected, as being a drier situation during the 

 period of early summer rains. A scanty lining of dry grasses keeps the 

 eggs from actual contact with the saturated moss of the foundation. 



The full set of eggs numbers from eleven to thirteen. They are very 

 deeply and closely spotted and blotched with chestnut-brown, the effect 

 being to render them difficult to distinguish from their surroundings. The 

 female does all of the sitting, and when approached on the nest does not 

 take flight until almost trodden upon. She then exhibits the greatest 

 solicitude, tumbling about within a few yards of the intruder in the most 

 distressing manner; but the male bird stays at a more discreet distance. 



After the eggs are hatched, the precocious young- 

 sters are accompanied by both parents. They then Precocious 

 have the faculty, like that of young quails and grouse, 

 of concealing themselves at a moment's notice, while the parents attempt 

 to call the intruder's attention elsewhere. The young at first are clothed 

 with yellow and brown down ; but before they are half-grown this is 

 entirely replaced by loose-textured feathers, and even before half-grown 

 the chicks are able to fly as readily as the adults. 



In summer, the Willow Ptarmigan's bill of fare includes many sorts 

 of insects, as well as green herbs. In the fall, the abundant crops of 

 blueberries, heathberries, cranberries, and roseapples are freely resorted 

 to, and these fruits again become available the following spring, when the 

 retreating snow leaves them exposed. 



The reader will have marveled already at the special and useful modi- 

 fications in the habits and structure of the ptarmigan, which enable it to 

 carry on a successful existence under so extreme a winter climate. Per- 

 haps the most wonderful thing about the bird is its alternating adaptations 

 to the opposite conditions of the short summer. Not 

 only is the summer plumage of a totally different gen- Molting 



eral color, as already described, but it is much less 

 dense than the winter plumage. The molts, however, do not affect the 

 feathers of every part of the body. Those of the wings and tail are 

 changed only at the time of the fall molt which, in fact, is the only com- 

 plete molt. The feathers of the feet and legs are not replaced in the 

 spring: but. as summer advances, the old feathers become brittle and TiVdr 

 off, until midsummer finds the birds with almost naked feet a heavy 

 feathering at that season probably being not only needless but a hindrance, 

 as it would certainly become when wet. 



The toe-nails in winter are so long as to project considerably beyond 



