234 THE GROUSE IN HEALTH AND IN DISEASE 



The rapid death of the eggs of Trichostrongylus pergracilis in feeces that 



have undergone temporary drying indicates that the drier the moor, the more 



efficacious will wind and sun prove as natural antagonists to " Grouse 



drainage, Disease." Again, as the infective forms of the parasite occur on the 



burning, 



and "food" heather, it is evident that the greater the amount of "food" 



cutting. i i 



heather in proportion to each bird, the less likely it is to become infected. 

 As the periodical burning of heather increases eventually, not only the area of 

 food heather, but at the same time destroys in the only effective way known 

 the living parasites upon the area of heather burned, the policy of heather 

 burning, advocated by other members of the Committee upon other grounds, 

 receives additional support. 



The practicability and value of a periodical cutting of the heather requires 

 further consideration by those acquainted with local conditions ; but, if practicable, 

 such a measure should not only be a means of ridding large areas of the moor 

 of infective material, and of bringing about a rapid increase in the " food " 

 heather area, but might also be applicable to those parts of a moor and in those 

 seasons of the year when burning is impossible. 



