ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
229 
Microbic Products which favour the development of Infection.*— 
M. G. H. Eoger finds that bacterial secreta have partly poisonous, 
partly vaccinative properties. There are therefore among these some 
which favour the development of certain viruses. This latter phase has 
been observed by the author in the bacillus of symptomatic anthrax. 
This bacillus, which by itself is harmless t(; rabbits, speedily kills them 
if another microbe be injected along wdth it. This can be done with 
Staphylococcus pyogenes aureus, Proteus vulgaris, and especially with 
Bacillus prodigiosus. 
A similar result can be obtained from the anthrax bacillus itself. 
For if the serum from an anthrax tumour be deprived of its cell- 
elements by means of a porcelain filter, 4-5 ccm. per kilo, of live weight 
can be injected without harm, while 1-1 • 5 ccm. coupled with the 
anthrax bacillus quickly kills. The morbid predisj^osition induced by 
such a procedure is, however, of short duration, lasting not more than 
24 hours, after which the animal again becomes refractory. Hence 
it would seem that a vaccinative effect is preceded by a period of 
diminished resistance to the virus. 
Another observation showed that the anthrax bacillus did secrete 
products favouring its development ; for while the virus, if injected into 
the thigh, was powerless, the same virus was found to be fatal if injected 
into the anterior chamber of the eye at one and the same time. Hence 
the products of the latter injection must have arrested the immunity in 
the muscles, and accordingly it may be concluded that the resistance of 
animals to infectious diseases can be affected by harmless as well as by 
pathogenic bacteria. 
Bacillus of Leprosy .f — Dr. 0. Katz mentions two series of experi- 
ments made by him to obtain cultivations of the leprosy bacillus. Both 
wmre failures. In the first instance leprous blood was inoculated on 
coagulated human hydrothorax fluid. The tubes were incubated in a 
thermostat for about two months at a temperature varying from 
30-34° C. No evidence of the multiplication of the bacilli was found. 
In the second series, pepton-glycerin-agar was used, and the tubes were 
incubated for a month at a temperature of 37° C. At the end of this 
period the tubes were still sterile. 
Bacillus isolated from a fatal case of Cholera Nostras. { — Dr. B. 
Schiavuzzi describes a bacillus which he isolated from the intestinal 
contents of a case of cholera nostras. The organism was separated in 
the usual way on gelatin plates, the colonies in 24 hours forming small 
milky -looking clumps, about 1 mm. in size. Under a 1/15 homo- 
geneous-immersion lens the colonies were found to consist of straight rods 
1 • 7-2 /X long, 0 • 85 /X broad. Every individual contained at both ends 
well-marked spores, which were also seen free. Both rods and spores 
stained easily with fuchsin. In hanging drops swarming movements 
were visible. Cultivated on potato the colonies were of a whitish- 
yellow colour, the rods grew larger, and the spores were very distinct. 
* Comptes Eendus, cix. (1889) p. 192. Cf. Ceutralbl. f. Bakteriol. u. Parasi- 
tenk., vii. (1890) pp. 60-1. 
t Proc. Linn. Soc. N.S.W., iv. (1889) pp. 325-8. 
X Bollettiuo Soc. Ital. Micr., i. (1889) pp. 45-50. 
