158 THE STRUCTURE AND LIFE OF BIRDS chap. 



after being fed daily are left to pick up their own food, 

 the moult is arrested. Bird fanciers hasten the moult 

 by putting their victims in a dark and rather cold 

 place. Pigeons, which do not pair, put off their moult, 

 and so are in splendid condition for flying. By some 

 process at present not understood in Europe, the 

 Japanese check the shedding of the tail feathers of 

 Cock Chickens, and so produce the enormous growths 

 (ten or twelve feet long) with which we are familiar. 

 The Ptarmigan moults no less than three times in 

 the year. After the nesting season he sheds many of 

 his smaller feathers and becomes gray ; in autumn he 

 moults again, and in winter is arrayed in white, with 

 feathers on his legs supposed to be intended to 

 prevent him from sinking into the snow. A partial 

 moult in spring arrays him in his breeding plumage of 

 black and gray-brown and white. The big wing- 

 feathers are white at all seasons. The claws are 

 shed in July and August, and have grown to their full 

 length again before the bird puts on his winter dress. 



The moulting of birds in their first year presents 

 great varieties. In most songsters it begins thirty or 

 forty days after they have left the nest. Hawks and 

 their allies keep their first plumage till next summer. 

 Young Ducks first appear in the same dress as their 

 parents in late autumn. Geese have only down feathers 

 till six weeks old ; after that appear feathers proper, 

 which they shed between September and December. 

 In their second autumn, like mature geese, they moult 

 completely in the space of four weeks. A young bird 

 of aquatic habits can afford to be content with a 

 covering of down for a long time after his birth. A 



