98 MICRO-ORGANISMS AND DISEASE [chap. 



{e) The bacillus anthracis in thirty minutes. 

 (/) The bacillus subtilis of hay infusion in twenty 

 minutes. 



{g) A filamentous bacillus liquefying gelatine, not mobile 

 and isolated from sewage, in eighteen minutes. 



{h) A mobile bacillus (bacillus fluorescens liquescens), 

 rapidly liquefying gelatine and common in ordinary London 

 drinking water, in eighteen minutes. 



(/) A bacillus, jion-mobile, non-liquefying, rapidly form- 

 ing spores, and slightly filamentous, isolated from London 

 sewage, in forty minutes. 



(/) The bacillus of the Middlesbrough pneumonia in 

 eighteen minutes. 



{k) The bacillus of fowl enteritis in twenty-four minutes. 

 (/) The bacillus of typhoid fever in thirty minutes. 

 {m) The bacillus diptheriae in forty-five minutes. 

 In all these instances a single organism lying isolated was 

 focussed and watched, and, after a distinct division had 

 been noticed, the time was marked, and the interval it took 

 for one of these to again completely divide was taken as the 

 time for a division. In these observations, which do not 

 claim more than approximate accuracy, it was remarked 

 that the division of the two members of the dumb-bell cocci 

 or dumb-bell rods does not proceed at the same rate, the 

 difference being as much as a quarter to a third of the whole 

 time. The above numbers indicate the average of three 

 successive divisions, and therefore they only represent 

 approximately the main periods that these several microbes 

 require for dividing under the above conditions. Buchner 

 {CentralM. filr Bad. und Parasit. II. No. i) calculated 

 the time required for the cholera vibrio for a division at 

 37° C, and found it to amount to twenty minutes on 

 an average. 



