76 THE GROUSE IN HEALTH AND IN DISEASE 



breast, giving the bird a very rich uniform red colour all over 

 the head and neck. In the hen, as a rule, the whole of the 

 feathers of these parts are crossed by narrow black bars, 

 giving her more of the mottled and broken colouring which the 

 cock bird only begins to assume in the early summer when 

 he puts on the first feathers of his autumn plumage. 



The feathers of the chin are a very useful indication of 

 sex from August to November, practically throughout the 

 shooting season, for the chestnut-red feathers which can be 

 found on the chin of the cock Grouse in every month of the year 

 will be sought for in vain in the hen at this time. Even in 

 December and January they are so imperfectly red as compared 

 with the same red feathers in the male that one may almost 

 say that red feathers are to be found on the chin of the hen 

 only from February to July, when they become conspicuous 

 on account of the contrast in colour with the increasing yellow- 

 ness of the breeding plumage. These red feathers persist from 

 her previous autumn-winter plumage exactly as do the feathers 

 of the lower breast and abdomen. 



This persistence of winter-plumage feathers on the chin, 

 lower breast, and abdomen is common to both cock and hen ; 

 but in the cock they remain, as a rule, until replaced by the 

 following winter plumage, persisting throughout the autumn 

 plumage change ; whereas in the hen they are persistent only 

 to June or July, and are entirely replaced during the autumn 

 change. Even when the autumn plumage is put on, the yellow 

 feathers of the preceding breeding plumage are almost always 

 to some extent persistent, and they are to be found in the chin 

 of the hen bird even though the throat and neck may be un- 

 usually red and therefore unusually like those of a cock bird. 

 From January to May there is no possibility, as a rule, 

 of confusing the sexes. In June and July confusion is unlikely, 

 but in August and onwards to December the differentiation of 

 the sexes by the plumage is sometimes a difficult thing, and the 

 best guide is the persistence of feathers of the preceding plumage 

 such as occurs upon the chin in particular. We must recollect 



