RELATION OF PATflOGENIC TO SEPTIC RACTERIA. 53. 



The experiments which I wish to mention here were made 

 Avith Bacillus anthracis derived from the mouse, guinea-pig, 

 or rabbit, killed by inocula^ed anthrax, after this bacillvis had 

 been cultivated in the neutral pork broth or the neutral gela- 

 tine pork above described. In the following I shall, of course, 

 only take into account the cultivations which from the unaided- 

 eye aspect, the microscopic examination, and the experimental 

 results of inoculation with them, are to be considered as undoubt- 

 edly pure cultivations of Bacillus anthracis. The first 

 remove of Bacillus anthracis from the anthrax animal 

 will be considered as the first cultivation; the remove from this 

 into a new cultivation, the second cultivation ; from this, 

 again, a third cultivation ; from this, again, a fourth, and so 

 on. As a rule, as soon as a cultivation showed a good crop of 

 the bacillus, a next cultivation was established from it by 

 transferring into the sterile nourishing material an infinitesimal 

 part of a drop of the parent cultivation. In some instances, 

 especially when the cultivations were kept at a temperature of 

 32 — 35° C, there was a copious growth of bacillus obtained 

 already after two or three days ; in other instances, if the in- 

 cubation was carried on at 20 — 25° C, I generally waited about 

 six or seven days before utilising the cultivation for the estab- 

 lishment of a new cultivation.^ To term the cultivations 

 " generations," as Buchner does, seems to me altogether arbi- 

 trary; his "1500 generations" are no more in reality 15U0 

 generations than they are " 150 generations," as Koch is only 

 too leniently inclined to admit (1. c, p. 24). A " generation" 

 could really only be called a new crop of bacilli produced from 

 spores of bacilli. If a bacillus grows out into a long con- 

 voluted thread or threads, i. e. if one or several elementary cells 

 continue to divide till they have formed a chain of enormous 

 length, then we have no more right to call this chain a full 

 generation than we have to consider the initial cell of the 

 bacillus thread as the parent, the second cell derived from this 

 as the first generation, the third cell as the second generation, 



^ For convenience's sake, I shall speak of the days of exposure of a cultiva- 

 tiou to a constant temperature in the incubator, as being dajs of " incubation." 



