THE STREPTOTHRICOSES 591 
Experiments at the Reproduction of the Disease. 
When the first culture was isolated it was injected into 
guinea-pigs; its loss stopped further work because it 
could not be regained from the animals. The present 
culture had been injected into guinea-pigs, rabbits, opos- 
sums — all with negative results; such an experience is 
not unknown for actinomyces. Intraperitoneal, intra- 
venous methods having failed, inoculation was made into 
the gums of rabbits and of opossums with no result, even 
after traumatizing the mucous membrane. The injection 
of about 5. mg. of a twenty-four-hour agar culture was 
made directly into the masseter muscle of an opossum 
without producing even a lump at the site. Atomizing a 
culture into the nose and throat of an opossum seemed 
also without effect. Injection of cultures into the nose, 
gums and labial tissues of a wallaby have been negative ; 
nor has any perceptible effect followed the atomizing of 
a heavy nocardial suspension in broth into the trachea of 
this animal. 
The results of these experiments are in accord with 
those of many similar attempts to reproduce actinomy- 
cosis. Perhaps in Kangaroo disease the small Gram- 
negative bacillus is a necessary factor. 
Specific Prevention and Treatment. 
Encouragement that we were upon the right track was, 
however, found in another direction. Improvement in 
human and bovine actinomycosis having followed the use 
of vaccines, it occurred to me to try this method as treat- 
ment and prophylaxis. The first culture to be isolated 
was just at hand, so that it could be used at once. Five 
injections were given under the skin of the thigh to a 
recently developed case of the ulcerative gingival variety, 
a noticeable improvement occurring almost at once, and 
at death there was an apparent cure of the local lesion. 
However, the accompanying protocol made at the time 
