OF THE BEITISH ISLANDS. 37 



threshold of a Canadian settler. In the second place, the straying of a species 

 from its accustomed haunts is purely abnormal a struggle for life, in fact, of an 

 individual, and such an action in the majority of cases would not save the species 

 from extermination if it succeeded in saving that individual. The conditions for 

 successful reproduction, found only in the normal haunts of the species, would he 

 wanting, and the inevitable result would be a more or less rapid extinction 

 throughout the area affected. Little need be said concerning Grouse-shooting. 

 The sport yielded by driven Grouse is certainly not equalled by any other winged 

 game ; and the man who can satisfactorily account for his cartridges after shooting 

 for an hour or so from the "butts," at birds that thunder by like sky-rockets, 

 need not be afraid to boast of his prowess. Very large bags are sometimes made 

 both over dogs and at the butts. The Bed Grouse is singularly subject to what 

 may well be termed a mysterious disease, seeing that its causes and nature are 

 but imperfectly understood. This disease (which is said to have been traced to 

 a parasitic worm, Strongylus pergracilis, breeding in the throat and rapidly 

 spreading to the other organs), appears specially to attack the liver and the 

 intestines ; but whether the worm is the primary cause of the disorder seems by 

 no means certain, for parasites of this character, if not of the same species, are 

 often common in healthy birds. Space forbids discussion of this disease here; 

 but I might remark that in the opinion of an old gamekeeper friend of mine, 

 it is very closely connected with the moulting of the birds. I offer this merely 

 as a hint to investigators. On the other hand, over-stocking of moors, both with 

 birds and with sheep, causes a short food supply, and brings the Grouse low 

 in condition, and makes them less likely to withstand incipient disease. Attempts 

 have been made to introduce the Red Grouse in some of the eastern and southern 

 counties at Sandringham, Holt, and other places. It is said that of fourteen 

 brace turned out at Sandringham in 1878, enough remained to produce three 

 broods in 1881. The small extent of moorland in these places seems fatal to the 

 success of the efforts. 



Nidification. The Eed Grouse is monogamous, and pairs early in the 

 spring. At this period the cock-birds stand on some bit of rising ground and 

 crow defiance to their rivals and invitation to the hens, sometimes accompanying 

 this call by jumping into the air or flapping their wings. Once paired, however, 

 there is no evidence to show that the cock ever mates with more than one hen. 

 The nest is slight enough, always on the ground, either among the ling and heath, 

 under the shelter of a boulder, or even amongst grass and rushes. Sometimes 

 it is made in frequented places, a yard or so from the highway or footpath; 

 whilst favourite nesting-grounds are near the patches of burnt heather burnt 

 for the purpose of furnishing a supply of young shoots for the Grouse where 

 doubtless the abundance of food influences the choice. The nest is merely a hollow 

 scratched out in the peaty soil and strewn with a few bits of withered ling, heath, 



