ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
685 
iEtiology of Cholera.* — During tho last epidemic of cholera in 
Baku Herren Blackstein and G. Schubenko made some experiments for 
the purpose of ascertaining whether other organisms besides the cholera 
vibrio might not play an effective part in the causation of this disease, 
or, in other words, they desired to find what influence was exerted by 
the locality and the contagion in determining an outbreak of cholera. 
Rabbits were subcutaneously injected with 1 ccm. of the supernatant 
clear fluid obtained from fresh rice-water stools which had been allowed 
to stand a while. The number of cholera vibrios in this fluid to all other 
organisms was found to be as 4-1. The animals died in three to five 
days with fits of cramps of the extremities and opisthotonus. The 
autopsy showed considerable oedema round about the injection place and 
fatty liver. Cultivations were also made of minute quantities of rice- 
water stools in 2 per cent, pepton solution, and having been incubated 
for twenty-four hours at 33°, 1/2 ccm. was injected subcutaneously. The 
rabbits died in about twelve hours. Microscopical examination of this 
cultivation showed that the number of cholera vibrios to other bacteria 
was as 1-10. 
Besides the cholera vibrio there were present Bad. coli commune and 
a new bacillus called B. caspicus. This microbe is about as thick as 
B. coli commune , and 2-5 times longer than broad. It is a mobile 
organism, and found both in the direct and indirect cultivations in 
company with the cholera spirochsete and some liquefying bacteria. 
Hence in the intestine the cholera bacillus predominates over the B. coli 
commune and B. caspicus , while in the transfer cultivations the reverse 
is the case. 
Subcutaneous injections on white mice and rabbits, made with mix- 
tures of the two organisms and with each kind separately, both with 
dejecta and cultivations therefrom, gave the following results : — (1) That 
the dejecta transferred to bouillon and incubated had a stronger action 
than the dejecta by itself. (2) That the mixture of the bacteria had a 
stronger action than the pure cultivations. 
Saline Constituents of Well Water and the Cholera bacillus.f — 
Dr. Trenkmann records the results of some preliminary experiments 
relative to the growth and viability of the cholera bacillus in natural 
waters. A well water, 100 ccm. of which reduced 3*1 ccm. of 1/100 
permanganate of potash solution, and of which 1 litre contained 35 mg. 
chlorine, served as the basis. A definite quantity of this was mixed 
with dilute solutions of various salts, chiefly sodium salts, inoculated 
with comma bacilli, and plate-cultivations were made from which the 
number of bacilli was determined. 
Speaking generally, it was found that the presence of sodium chloride 
and some other salts of the same base was very favourable to the develop- 
ment of the bacillus. Such results are only of scientific value for the 
particular spring water experimented with. 
Involution Form of Tubercle Bacilli. ;£ — Dr. S. G. Dixon observed, 
in 1889, that tubercle bacilli cultivated in agar and glycerin exhibited 
* Wratsch, 1892, No. 41, p. 1029. See Centralbl. f. Bakteriol. u. Parasitenk , 
xiii. (1893) pp. 441-2. 
f Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 313-20. 
X Proc. Acad. Nat. Sci. Philadelphia, 1893, pp. 100-3. 
