iv.] ARTIFICIAL COMMA-BACILLI. 75 



comma-bacilli are originally present in very large numbers 

 in the mucus- flakes of the rice-water stools, a couple of 

 plate-cultivations reveal the presence of numerous colonies 

 of the comma-bacilli. 



In nutritive gelatine contained in tubes the comma-bacilli 

 grow in a typical manner. On inoculating by first dipping 



F G H 



FIG. 25 continued. 



(E) Cultivation of comma- bacilli from the fluid of the mouth (healthy). 

 F) Cultivation of choleraic comma-bacilli. In both E and F the medium is the 

 same (alkaline gelatine peptone broth), and the inoculations were made within 

 a few minutes. 



(G) Cultivation of mouth comma-bacilli in gelatine peptone broth. 

 (H) Cultivation of choleraic comma-bacilli in alkaline gelatine peptone broth; the 

 inoculation was made on the surface. 



the platinum wire or the pointed end of a capillary glass 

 pipette into a pure culture of comma-bacilli, and then 

 pushing it into the (solid) nutritive gelatine, and exposing 

 the tubes to a temperature of about 20 C, pure cultivations 

 of the comma-bacilli are obtained in a few days. After the 

 lapse of a couple of days the channel of inoculation be- 

 comes marked as a greyish line, this as growth proceeds 



