66 THE GROUSE IN HEALTH AND IN DISEASE 



A few paler feathers of the preceding autumn plumage still 

 remain (see PL iv.). When these autumn feathers are numerous 

 they may be regarded as a result of delayed moult caused by 

 sickness. 



February. Full winter plumage. Autumn feathers are still 

 present, but are only numerous in very backward birds. 



March. Full winter plumage but very forward birds may 

 show a few new autumn feathers ; some old autumn feathers 

 are still present even in healthy birds. 



April. Winter plumage is still the main character, but new 

 autumn feathers are beginning to appear on the neck and mantle. 

 The feathers of the feet and neck are beginning to moult, and 

 bareness of legs in this month is a sign of health (see PL v.). A 

 few old autumn feathers still remain on the back and rump. 



Nearly all birds picked up dead in this month and in May 

 are very backward, and have not yet assumed the full winter 

 plumage which they should have completed in December. 



May. A larger number of autumn feathers have appeared, 

 but the winter plumage is still predominant, though by now 

 it has become worn and dingy. 



June. Late in this month the autumn plumage begins to 

 prevail, though winter feathers still remain on the abdomen, 

 lower breast, neck, and throat. In this month the quills and 

 tail feathers commence to moult. 



The autumn plumage may be described as follows : Head 

 and neck, breast and throat, broad-barred buff and black feathers 

 not so rich or finely black-marked as the winter plumage. Back 

 and rump black-centred feathers with broad-barred buff and 

 black bands, a few with a whitish terminal spot. 



July. Full autumn plumage, the general appearance is 

 much lighter in colour tone than the winter plumage. The 

 wing and tail feathers are in full moult, the claws also are ready 

 to be shed ; but the feet and legs are beginning to grow new 

 feathers. It should be noted that even in this month the winter 

 plumage is still retained on the abdomen and lower breast ; 

 there is no second moult or replacement of these feathers. 



