ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
665 
infectious serum which, when used on mice, pigeons, and rabbits, is found 
to have preventive properties, and, further, to be curative up to 24 hours 
after the introduction of the virus, provided that the infection have not 
already become generalised. 
In vitro the serum is not bactericidal ; it is endowed with marked 
agglutinating properties, even when strongly diluted. The agglutinated 
microbes do not lose their virulence, and the bacill', in the immunising 
serum, form chains composed of a large number of joints. 
The body-juices of mice, passively immunised, do not exert any action 
on the microbes, their destruction being due to the action of phagocytes 
which incorporate them in a living virulent condition. The serum, 
then, is a stimulant to the cells charged with the defence of tho 
organism. 
The virus was introduced either into the abdominal cavity or injected 
beneath the skin of the belly. 
Contagious Pneumonia': of Guinea-pigs.* — M. M. G. Tartakowsky 
describes a malady affecting laboratory guinea-pigs, tho most prominent 
feature being an acute pneumonitis. The causative organism closely re- 
sembles the bacillus of glanders in size ; the rodlets have rounded ends, 
and are 2-3 times as long as broad. They are usually in pairs. They 
are easily stained, but not by Gram’s method. Neither spores nor spon- 
taneous movements were observed. On glycerin-gelose or on gelose 
the growth is greenish-blue, while on gelatin and potato it is brownish- 
yellow. Milk is not coagulated. It is strictly aerobic, and is sensitive 
to the reaction of the medium, growing fairly well in neutral media, best 
when the reaction is slightly alkaline, and not at all when acid. 
The distribution of the microbe in the body of the guinea-pigs is 
limited to the respiratory organs ; even when the animal is infected ex- 
perimentally by subcutaneous inoculation, the organism is found only at 
the site of injection. 
Intraperitoneal inoculation killed guinea-pigs in 30-36 hours ; 
rabbits take the disease when inoculated, but are not affected naturally 
or spontaneously. The name proposed for this hitherto undescribed 
disease is Pneumonia contagiosa bacillaris caviarum. 
Achalme’s Bacterium and Acute Rheum atism.j — Prof. I. Sawt- 
cenko confirms the observation of Achalme,]: that in the blood of persons 
sick with acute rheumatism there exists a specific anaerobic bacterium. 
Pour times out of six the bacterium was obtained in a state of purity, 
once mixed with Streptococcus , and once the results were negative. The 
most favourable cultivation medium was lactose-bouillon mixed with 
milk, the reaction being slightly acid. 1 ccm. of blood was mixed with 
10 ccm. of the medium. 
The bacterium, the morphological and cultural characters of which 
are not described, secretes substances endowed with negative chemiotaxis 
and necrotic properties. 
Injection of filtrates of virulent cultures appeared to increase the 
immunity of animals. The presence of salicylate of soda diminished 
* Arch. Sci. Biol. St. Petersbourg, vi. p. 255. See Ann. de Micrographie, x. 
1898) pp. 228-32. f Ann. <le Micrographie, x. (1898) pp. 220-2. 
+ Ct‘. this Journal, ante, p. 119. 
