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intestinal inflammation. It is not a little difficult to estimate the exact 
value of these observations in general. One is quite prepared to believe 
that worms exercise a harmful influence in the intestine and that they 
may aid in causing disease when the necessary other factors are present, 
but that they are in themselves a specific cause of inflammatory lesions 
is opposed to present bacteriological views. It must not be forgotten 
that such worms as are incriminated, namely Ascaris lumbricoides, 
Oxyuris vermicularis and Trichuris trichiura, are extremely common 
amongst certain classes of the community and that as a rule they give 
rise to few symptoms. Their frequent occurrence, therefore, in cases 
of disease which are brought under notice, is not to be wondered at. 
There is a certain element of coincidence, moreover, for Ascaris 
lumbricoides and typhoid fever, for instance, are both correlated with 
the same insanitary conditions. 
Passing on now to diseases of animals. I would specially select two 
which have aroused interest and concern in this country. The first of 
these is grouse disease. For many years, even for at least a century, 
the grouse of this country have been subject to severe periodic epidemics 
of disease. These occurrences give rise to much speculation, but it was 
not until 1865 that an earnest attempt was made to thoroughly 
investigate the matter. The result of that investigation provided two 
conflicting opinions, namely that of Klein who held that the disease was 
of bacterial origin, and that of Cobbold who showed that parasitic 
Nematode worms were a very likely cause. The recent commission on 
grouse disease has made a very thorough study of the disease, and the 
results published last year have demonstrated the correctness of 
Cobbold’s views. The parasite in question is a Strongyle worm 
(Trichostrongylus pergracilis) which infects the coeca in enormous 
numbers. Chief credit in this work is due to Shipley and Leiper, who 
have made a careful study of the anatomy and life-history of the 
parasite. 
Another disease which has caused considerable uneasiness in this 
country is what is known as Onchocerciasis or worm nodules in cattle. 
This was first brought into prominence by its discovery in frozen carcases 
imported from Australia. It was the subject of much alarm and called 
forth a special inquiry by the Local Government Board. Leiper (1911) 
succeeded in demonstrating the exact nature of the disease and its 
harmlessness to man. The nodules are caused by parasitic Nematodes 
of the Filaria family, namely Onchocerca gibsoni. The parasite does not 
apparently injure the health of the animal, but it renders the meat 
