384 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Mycoderma aceti, that, in very small quantities, so far from having a 
microbicidal influence, ozone favours the development of some organisms. 
A similar series of experiments is recommended on the pathogenic 
bacteria. 
Thermogenous Bacteria.* — Experiments carried on by Prof. F. Cohn 
on the cause of the so-called “ spontaneous combustion ” of masses of 
cotton, grass, tobacco, &c., have led him to the conclusion that it is 
invariably due to a fermentation caused by thermogenous bacteria. No 
perceptible rise of temperature takes place in heaps of cotton, whether 
dry or moist, or even if saturated with oil, when the presence of bacteria 
is carefully excluded. The special micro-organism concerned in the 
combustion of cotton appears to be a Micrococcus which is present in 
great quantities in the soil of the cotton-plantations. 
Aceto-bacteria.f — Herr E. C. Hansen gives further details respecting 
the life-history of the bacteria which produce acetic fermentation, viz. 
Mycoderma aceti and M. Pasteur ianum , to which he now adds a third 
species, M Kutzingianurn. All these species occur in three distinct 
forms, — as long filaments, as swollen bodies, and as chains ; and the 
author has determined, by culture-experiments, that the second of these 
forms is an intermediate stage of development between the other two. 
Conversion of Starch into Sugar by Bacillus anthracis.J — 
M. Maumus states that when Bacillus anthracis is grown on potato, the 
starch contained in the substratum is gradually transformed into sugar, 
which subsequently disappears, being probably used up as nutriment by 
the microbe. 
Composite [Cilia of Baciilus.§ — M. N. Sakharoff describes a microbe, 
Bacillus asiaticus , which was isolated from cholera stools. It is a mobile 
bacillus, 4 /r at least long by 1 p, broad, with rounded ends, and some- 
times forms long threads and chains. It can be cultivated on the usual 
media, liquefies gelatin rapidly, is aerobic, and not pathogenic to guinea- 
pigs. The colonies on plates are circular or oval, and white or yellowish 
in colour. The chief interest of the organism is the presence of spiral 
cilia, easily observed without staining, and best from puncture gelatin 
cultivations at 24-36 hours after inoculation. They are motionless ; 
the turns are quite regular, but the number of turns and the thickness of 
the cilia are variable. The author thinks that the spirals are the result 
of the union of the cilia of several bacilli. The Loeffler mordant was 
found to be inapplicable ; but after weakening the action of the sulphate 
of iron by making the solution at the ordinary temperature satisfactory 
results were obtained. This modified solution was allowed to act for 
5-10 minutes, and after staining with Ehrlich fuchsin the cilia were 
well seen. 
Gas and Acid Production by Bacteria.|]— Dr. Th. Smith finds, from 
experiments made with Bacterium coli commune , the hog-cholera group, 
* Ber. Deutsch. Bot. Gesell., xi. (1893) Gen.-Versamml.-Heft, pp. 66-9. 
t Tom. cit.„ pp. 69-73. 
X Compt. Rend. Soc. Biol., 1893, pp. 107-9. See Journ. Chem. Soc., 1894, 
Abstr., p. 62. § Ann. Inst. Pasteur, vii. (1893) pp. 550-3 (3 figs.). 
|| Wilder Quarter-Century Book, 1893, pp. 187-232. See Centralbl. f. Bakteriol. 
u. Parasitenk., xiv. (1893) pp. 864-7. 
