214 
Piroplasma canis 
remains that the jackals had had the disease before they were captured 
and consequently that their immunity was acquired. Nevertheless, 
this possibility appears remote in the case of the second animal, which 
was captured as a young pup, and was maintained in captivity for six 
months before it was inoculated with virulent blood. 
Conclusions. 
The foregoing experiments appear to indicate that P. canis is 
peculiarly specific in its pathogenicity, since it is incapable of producing 
disease in the fox and the jackal, species closely allied to the dog. They 
also seem to show that neither of these species is concerned in the 
maintenance of the disease in nature. Experiments on the wolf would 
be extremely interesting. 
REFERENCES. 
Nuttall, 6. H. F. (1904). Canine Piroplasmosis I. Joum. of Hygiene , rv. 
219—252. 
Nuttall, G. H. F. and Graham-Smith, G. S. (1905). Canine Piroplasmosis II. 
Journ. of Hygiene , v. 237—249. 
