RED GROUSE 
mucous membrane becomes highly inflamed and incapable of absorbing 
nutriment. The food, consequently, remains in the caeca undigested and 
in a dried up condition. The nematodes meanwhile flourish vastly, and 
find perfectly congenial surroundings among the mass of rotting matter ; 
but the poor grouse rapidly loses weight and condition, and presently 
dies. The fact is, to put it in plain English, that the most fatal disease 
among grouse is appendicitis in its most acute form, for, unlike the 
human subject, the grouse possesses two appendices, which play a highly 
important part in its economy, and these are rendered functionless owing 
to their inflamed condition. This disease has been named Strongylosis. 
A few species of nematode worms lead an entirely free life, but 
Trichostrongylus pergracilis is parasitic in the grouse in its mature stage. 
Practically every grouse contains these worms in scores, if not in hun- 
dreds, each worm lays thousands of eggs, and every grouse -dropping 
contains hundreds of fully segmented eggs and of larvae free or still con- 
tained in the egg-shell. It can, therefore, be easily realized that the larvae 
are scattered in countless millions over the grouse moors. Dr Shipley 
writes : “ The eggs give rise to larvae in about two days, the larvae sur- 
round themselves, about the eighth day, with a capsule or cyst, and under- 
go ‘ a rest cure.’ After a period of quiescence they quickly change into 
second and active larval forms, which are minute, transparent, and quite 
invisible. These lead a perfectly free life, and in wet weather gradually 
squirm and crawl among the leaves and flowers of the heather, where 
they remain until swallowed by the grouse. When once inside the grouse, 
the larvae make their way along the alimentary tract and enter the caeca, 
where they rapidly develop into adults.” That is, briefly, the explanation 
of the worst form of grouse disease. 
Dr R. T. Leiper, who has assisted the Committee by working out the 
development of this small threadworm, concludes his account with the 
following remarks : ” The rapid death of the eggs of Trichostrongylus 
pergracilis in faeces that have undergone temporary drying indicates that 
the drier the moor the more efficacious will wind and sun prove as 
natural antagonists to ‘ Grouse Disease.’ Again, as the infective forms 
of the parasite occur on the ‘ food ’ heather, it is evident that the greater 
amount of ‘ food ’ heather in proportion to each bird, the less likely is it 
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 
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