24 
Journal of the Mitchell Society 
[May 
CULTURAL EXPERIMENTS 
( A) Wads . — In both the cultural and animal experiments the 
wads were extracted with a sterile instrument, every care being 
taken to exclude accidental contamination. 
The wads were placed in a 1 per cent, glucose bouillon, and 
incubated under anaerobic conditions (usually in Novy jars) at 
body temperature, for from 3 to 5 days, when coverslip prepara- 
tions were studied. Not infrequently slender bacilli with end 
spores suggestive of B. tetani were seen. Nine cultures containing 
these tetanus-like bacilli were inoculated in fresh hematoma in the 
thigh of guinea-pigs. All of these animals survived but one, 
which died at the end of the month without symptoms of tetanus. 
These tetanus-like bacilli decolorized by Gram and were proved 
by cultural methods to be identical with a pseudo-tetanus bacillus 
discovered by Bain in blank cartridges. Many cultures contained 
a stout bacillus with square ends, apparently encapsulated, and 
subcultures made on glucose agar showed abundant gas formation. 
Nine rabbits injected with these gas-forming cultures, and killed 
ten minutes afterward, showed after from 8 to 20 hours’ incuba- 
tion marked gaseous emphysema, and B. aerogenes capsulatus was 
isolated from them all in pure culture. All efforts to demonstrate 
the presence of B. tetani failed. In a total of 250 wads examined 
by culture, the B. aerogenes capsulatus was demonstrated in sixty- 
six, or 26.4 per cent., and from sixty-one it was isolated in pure 
culture. Two of these were worked through all media, but in 
general the cultural characteristics on glucose agar, milk, and 
blood serum, together with the morphology, the capsule formation, 
the positive Gram stain, and the failure to grow aerobically, were 
deemed sufficient for identification. It is interesting to note that 
spore formation occurred in old milk and agar cultures, as well as 
on blood-serum. Some difficulty was experienced in separating 
B. aerogenes capsulatus from the other anaerobic organisms present 
in wads until Kitasato’s method of heating for one hour at 80 
degrees C. was adopted. It invariably survived this. That the 
explosion of cartridges neither kills nor inhibits the growth of B. 
aerogenes capsulatus was demonstrated by shooting the wads into 
jars containing melted glucose agar, which on incubation gave 
