RELATION OF PATHOGENIC TO SEPTIC BACTERIA. 65 



of starting a new cultivation, whose activity is also weakened, 

 that is to say, the bacillus having become modified by time, 

 transmits to its offspring this acquired mitigation. In the 

 case of the cultivations of Bacillus anthracis in neutral 

 pork or gelatine pork there was nothing of the sort. As 

 long as a cultivation, no matter which, contains living Bacillus 

 anthracis, it is capable of starting a new cultivation, and 

 this as well as its parent is capable of killing guinea-pigs and 

 rabbits. 



All that has been said of the first, second, third, fourth, 

 fifth, and sixth cultivations of Bacillus anthracis in neutral 

 pork broth holds good for the tenth, eleventh, twelfth, thir- 

 teenth, and so on cultivations. In no instance have I seen, 

 with reference to its infective power on mice, guinea-pigs, and 

 rabbits, any difference of behaviour from that mentioned of 

 the previous cultivations. 



It is altogether impossible for me to understand how Green- 

 field ('Veterinarian,' 1881) could have come to the conclusion, 

 that once arrived at the eighth cultivation, he already knew that 

 no fatal effect could be produced with it. He has tried the 

 effect of his cultivations on mice, guinea-pigs, and rabbits ; 

 but with pure cultivations of anthrax bacillus, the result is 

 to some extent the reverse, since guinea-pigs and rabbits are 

 killed by any cultivation, provided there are living anthrax 

 bacilli in it. 



The conclusion, it seems to me, forces itself on us, that 

 Greenfield's like Buchner's cultivations were impure, and the 

 further away from the earlier cultivations the smaller the 

 number of the anthrax bacilli, until the contaminating 

 innocuous bacillus gets altogether the mastery in the culti- 

 vations, and then the anthrax bacilli gradually disappear 

 altogether. 



Of the power of resistance spores are capable of, an idea 

 may be gained from the following facts : 



I have tried to ascertain whether the spores of Bacillus 

 anthracis in my cultivations become killed, like the bacilli 

 themselves, through boiling or freezing. As regards the first 



VOL. XXIIl. — NEW SER. E 



