THE GROUSE SUBFAMILY 17 



pine and birch forests spending most of its time amid the branches, 

 and roaming to the open moors and stubble to feed, gathering on the 

 latter in enormous flocks, morning and evening. 



Whatever may prove to be the cause of the discrepancies in the 

 published records of the habits of the black-grouse, it is clear that it 

 possesses greater powers of adaptability than is displayed by the 

 capercaillie, and hence the more restricted range of the latter. 



What is true of the blackcock in this matter of adaptability is 

 true also of the grouse, or, to be more exact, of the red-grouse, though 

 its chosen environment differs. Wherever heather and ling flourish, 

 from the sea-level to the rock-strewn summits of the highest moor- 

 lands, there may grouse be expected, for such plants furnish their 

 favourite food. But, be it noted, there are large areas in Scotland, 

 England, and Ireland where these birds also thrive, though they must 

 depend for food throughout the greater part of the year on grass and 

 rush seeds, and the leaves and fruits of the common crowberry 

 (Empetrum nigrum) ; but when the autumn comes they feast riotously 

 on grain gleaned on the corn-fields, and on all wild fruits within their 

 reach, especially blueberry, blackberry, cranberry, and cloudberry. 



As might be supposed from the extent of their vertical range, 

 grouse suffer much during the later autumn and winter months when 

 these happen to be visited by unusually severe weather. Roaming 

 about in small packs of both sexes, broods of the year or females 

 alone when the weather is open and mild, gales or heavy snow 

 speedily effect a union of the scattered packs, followed, in the case of 

 the birds haunting the higher ground, by a migration to the more 

 sheltered valleys. Here, even if there be heavy snow, they contrive 

 to find a living, but only if the winds be high enough to blow the 

 snow into drifts, leaving bare patches, whence food can be obtained. 

 When the snow lies deeply, and uniformly, from lack of wind, or snow 

 followed by a partial thaw and renewed frost, locking up all food, 

 they speedily feel the pinch of hunger, and then migrate for great 

 distances, travelling in immense packs. Such an exodus, Mr. Millais 



VOL. iv. c 



