64 DR. E. KLEIN. 



cultivations of the Bacillus anthracis carried on in acid 

 pork broth. I have made a sufficient number of observations 

 to state this positively, and I have seen such a cultivation 

 losing its infective power both for animals and for new cultiva- 

 tions after five days, no other organism making its appearance 

 in it, and the original mass of Bacillus anthracis having 

 altogether broken up. 



The important statement by Pasteur that ^'each of these 

 conditions of attenuated virulence may be reproduced by 

 culture/' is not borne out by my observations, since every one 

 of the cultivations containing only anthrax bacilli but no 

 spores, and incapable of producing any effect on mice, is in- 

 variably capable of starting a new cultivation proving fatal to 

 all rodents when used fresh. 



I have before me a fourth cultivation of Bacillus anthracis 

 in neutral pork, which had proved fatal to guinea-pigs and 

 rabbits. It had never any spores, and the days for its activity 

 on mice had passed. After the lapse of two months it was 

 again examined, and there were found in it bundles of dege- 

 nerated bacilli, as well as a few good bacilli. Inoculated into 

 a guinea-pig in minute doses it proved without result, but it 

 started a good and copious new cultivation of typical anthrax ba- 

 cillus threads, which killed a guinea-pig with typical anthrax 

 in twenty hours. Pasteur maintains that if a cultivation is 

 weakened in activity by keeping it for some days, it is capable 



invariably fatal result produced by the same bacillus on mice, guinea-pigs, and 

 rabbits. 



It is very curious to find that Greenfield talks (' Veterinarian,' 1881) of a 

 certain immunity against fatal anthrax conferred on cattle by liis artificial 

 cultivations, although these animals showed considerable illness after a further 

 inoculation with blood of man or guinea-pig dead of anthrax. He had already 

 learned that cattle do not die after blood inoculation, even when not inocu- 

 lated previously with any artificial cultivation. If he had inoculated his cattle 

 with the blood of a guinea-pig or man (woolsortcrs' disease), without pre- 

 viously inoculating them directly with artificial cultivations, the result would 

 have been precisely the same This appears to me to furnish decisive evidence of 

 Greenfield having had to deal, not with cultivations of Bacillus anthracis, 

 but with some other harmless bacillus. 



