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DR. BILLINGS. 
assistant Dr. Bowhill) upon my investigations upon swine plague 
in Nebraska will remember that I have been very cautious about 
claiming identity between that disease and Schutz’s u Schweine- 
seuche,” even though I can find no morpho- or biological differen¬ 
tiation between his micro-organism and that discovered by me. 
That the latter is the true micro-organism of this one species of 
hog cholera has been proven so conclusively by numerous ex¬ 
periments as to place that question beyond all doubt. With regard 
to the American disease I can only say at present that so far as 
my investigations have extended I have never missed more or 
less extensive pulmonary lesions, and that I have seen numerous 
cases, in the field especially, in which ulcerative alone, or the 
peculiar ulcerative-neoplastic cireumscribed-indurative lesions were 
entirely wanting in the large intestine; though the mucosa was by 
no means free from irritative complications. 
There is no doubt that Hueppe is correct in assuming that we 
have in these various diseases a group, the etiological movements 
of which bear the closest relation to one another, but the micro¬ 
coccus of hen cholera is, morphologically at least (according to all 
descriptions but Huppe’s), quite a distinct organism from that of 
rabbit septicaemia as is that of our swine plague from the latter; 
the uncolored space in the bacterium of American swine plague 
is more extensive than in the bacteria of rabbit septicaemia, and 
more distinctly marked. There is no reason why two similarly 
appearing or even biologically developing micro-organisms should 
not have entirely different pathogenic action. In such cases they 
can only be distinguished by the disease produced. Now hen 
cholera will not produce hog cholera, that is, the real swine plague 
if feeding experiments can be depended upon. There is no evi¬ 
dence, that I know of, of inoculative experiments; hence ITueppe’s 
assertions on that question fall to the ground. 
The same is true with regard to swine plague producing hen 
cholera, so far as I can judge from the experiments of others. 
To my mind this question of the identity of bacteria, or the 
identical etiological connection between them, is not to be de¬ 
cided upon morphological cr biological data, but rather by their 
pathogenic activities entirely. The facts which should decide 
such a question are: 
