634 
D. E. SALMON. 
absolutely impossible for me to get any culture of this organ¬ 
ism, but last summer Dr. Detmers sent me a slide marked as 
follows : ‘ Bacterium Salmonidi,’ on one label, and on the other, 
‘ Doctor B. Persh, culture in gelatine, 10, 24, ‘86.’ This or¬ 
ganism bears no relation to anything described by Mr. Sal¬ 
mon, either as to the germ ol swine-plague in ’85. or of his 
hog cholera in ’86, except perhaps in outline morphology ; it 
is a small, ovoid organism, about three times as long as wide, 
and has rounded ends, but colors, or is colored entirely, and 
it does not seem as if the tinction had been too strongly ap¬ 
plied. Sometimes, when in process of fission, there does seem 
to be a very slight clear space in the middle of the body, but 
in no way does it resemble Mr. Salmon’s description or plates, 
with the exception of the very latest, where the ends do color 
somewhat. 
“ Is this Mr. Salmon’s ‘ hog-cholera’ bacterium ? 
“ As to that I know not, but I will permit Dr. Detmers to 
tell his own story about it.” 
This is very peculiar writing for a bacteriologist. The 
organism, he says, bears no relation to anything described by 
me, except perhaps in outline morphology. In what other 
respect would he expect a resemblance in a mounted prepar 
ation of germs? We certainly have had very little informa¬ 
tion from any writer as to the internal structure of bacteria 
What he means, no doubt, is that the staining did not corres¬ 
pond with the description in the Bureau reports. It should 
be remembered, however, that that description was expressly 
stated to apply to the germs as stained in cover-glass prepar¬ 
ations from the blood and organs of affected animals. Our 
* 
photographs of stained germs from cultures, given in the re-: y 
port for 1886, show the germ solidly stained. Ii 
It is certainly well known to every bacteriologist that 
germs of the same species, grown in different media, vary 
morphologically, and, therefore, if a description is to be veri 
fied the conditions must be the same. The typical prepara¬ 
tions, showing the end staining of the swine-plague germsr 
and the unstained middle belt, are most reliably obtained^ 
from the blood and other tissues of affected animals. TQe 
