ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
83 
living substance of the bacteria, it forms with the protoplasm a cora- 
bination capable of maintaining itself in vacuo. 
Action of Bacillus pyocyaneus on Anthrax.^ — Owing to the experi- 
ments of Bouchard, who found that inoculation with Bacillus pijocyaneus 
had some effect on the development of anthrax, MM. Charrin and 
L. Gui guard have endeavoured to ascertain the mechanism of this 
influence by examining in vitro the action of the microbe of blue pus 
upon that of charbon. With this intent the pus bacillus was sown in 
active charbon cultivations. Guinea-pigs were inoculated with the 
mixed cultivations. During the first six days the virulence of the 
anthrax was not modified in any constant manner, but from the eighth 
day the virulence was diminished ; thus, while a pure anthrax cultivation 
killed in three or four days, the mixed culture required seven or eight 
days. From the twentieth day, although the results were not constant, 
the guinea-pigs became immune. It is noteworthy that if the attenuated 
virus be sown in pure bouillon, the germs regain their virulence. The 
diminished virulence is accompanied by morphological modifications ; 
involution-forms make their appearance, and spores are not developed. 
The authors conclude that in the attenuation of the charbon microbe 
by -that of blue pus, the products of the latter play some part, and this 
first by secreting some substance harmful to the development of charbon, 
and secondly by using up the nutritive medium. 
Anthrax, Tuberculosis, and Actinomycosis. t — Prof. E. M. Crook- 
shank publishes seven reports relating to anthrax, tuberculosis, 
and actinomycosis, containing numerous facts hitherto misunderstood 
or overlooked. The two papers on anthrax relate to the disease in swine 
and horses. It had been hitherto presumed that while swine died 
after eating carcases of animals dead of anthrax, they were not really 
susceptible to the disease. Now Prof. Crookshank succeeded in infecting 
swine with true anthrax ; consequently the liability of swine to suffer 
from this disease is set at rest, while the same observations also go to 
prove that the anthrax organism does not grow readily in the pig. 
The report on tuberculosis was instituted chiefly with regard to the 
infectivity of milk, and also to tubercular mammitis. It was found that 
the milk of cows suffering from tubercular mammitis contained tubercle 
bacilli ; and, taking into consideration that the milk of cows is, in dairies, 
mixed together before distribution, it is laid down that there is danger 
in using such milk. The report concludes with a case of transmission 
of the disease from man to cows, and general remarks on the tubercle 
bacillus. In these remarks it is shown that while the disease is common 
to many animals, the pathological expression of the disease is different 
in different species and individuals, and also that there are morphological 
differences in the bacilli. 
The third disease, actinomycosis, is discussed at considerable length, 
but at the same time with perspicuity, and these four paj^ers form 
together the best resume of the subject in the English language we have 
seen. This fungus disease, which has been found to attack almost every 
* Comptes Rendus, cviii. (1889) pp. 764-6. 
t ‘Annual Report for 1888 of the Agricultural Department Privy Council Office, 
on the Contagious Diseases, &c., of Animals (Appendix),’ 1889, pp. 20-128 (23 pis.). 
G 2 
