10 
D. E. SALMON'. 
There is an idea among some investigators that the lung lesions 
of infectious pneumonia or swine-plague and the bowel lesions of 
hog cholera are produced by the same bacteria and, that the seat 
of the disease depends entirely upon the organ through which the 
germ is introduced into the body. To illustrate this matter we 
have injected the germs of hog cholera directly into the 
lung tissue, but we have not produced hepatization by such inoc¬ 
ulations. Either the germ is diffused through the body, producing 
lesions of the spleen, lymphatics and intestines, or the animals re¬ 
cover. We have found, however, that in the lung lesions accom¬ 
panying hog cholera there are a much greater number of germs 
than in the healthy portions of the lungs. It is evident, therefore, 
that in these collapsed portions the germs find favorable condi¬ 
tions for their multiplication, and it is not unlikely that the collapse 
developes into broncho-pneumonia because of their multiplication. 
To determine whether the microbe of contagious pneumonia was 
present in the affected portions of the lungs from animals affected 
with hog cholera, sixteen rabbits were inoculated from the same 
number of lungs. Of these, eight lungs were affected with simple 
collapse and eight with broncho-pneumonia. Of these sixteen 
rabbits, four survived and the remainder died of hog cholera. The 
germ of contagious pneumonia or swine-plague evidently was not 
present in any one of these cases. 
When either cultures of this motile germ, or the spleen or in¬ 
testines of hogs which have died of cholera, are fed to susceptible 
pigs, there is produced the most remarkable and extensive ulcer¬ 
ative lesions of the intestines. In the most severe cases there 
is complete necrosis of the mucous membrane of the caecum and 
colon and often of the ilium, while in cases produced in the 
ordinary course of infection the small intestine is seldom if ever 
so affected. 
The germ of hog cholera produces fatal effects when inoculated 
in mice, rabbits, guinea-pigs, pigeons and pigs. 
In July, 1886, we recognized a different and distinct disease 
of swine in which the most prominent lesions were found in the 
lungs. This affection appears to begin as a broncho-pneumonia, 
but this extends—the lung tissue becomes completely hepatized, 
