GENUS BACTERIUM 215 



Gelatin. Ordinarily it does not grow in gelatin. 



Potato. It does not grow on potato. 



Serum. The growth is slight and often does not appear. 



Bouillon. Alkaline peptonized bouillon becomes uni- 

 formly clouded in 24 hours when kept at a temperature of 

 36 C. Occasionally cultures are obtained in which the growth 

 appears in the form of flocculent masses, but usually after a 

 few generations these disappear and the liquid becomes uni- 

 formly cloudy. If the bouillon contains any dextrose or 

 muscle sugar, its reaction becomes acid in 24 to 48 hours, owing 

 to the fermentation of the carbohydrate. With the virulent 

 cultures the liquid usually clears within a few days. The 

 small amount of grayish sediment becomes viscid after some 

 days, and upon agitation it is forced up, appearing as a some- 

 what twisted, tenacious cone, with its apex at or near the sur- 

 face of the liquid. Frequently a thin, grayish, somewhat 

 viscid band composed of bacteria is found on the sides of the 

 tube at the surface of the liquid. It will not grow in acid 

 bouillon. If the bouillon contains from 1 to 2 per cent glu- 

 cose, the growth is slightly more vigorous. 



In the fermentation tube, alkaline bouillon containing 

 sugars becomes uniformly clouded in both branches. Gas is 

 not produced. In bouillon containing dextrose and saccharose 

 the reaction becomes strongly acid in 24 hours, but the reac- 

 tion of alkaline bouillon containing lactose is not changed. 



Milk. Milk inoculated with this organism remains un- 

 changed in appearance for several weeks. "When boiled, after 

 this period, the casein is not coagulated. 



Life conditions and properties. Bad. suisepticum is 

 aerobic and facultative anaerobic. It grows best at the tem- 

 perature of 36 to 37.5 C. It multiplies slowly at room tem- 

 perature. It does not produce a poisonous soluble toxin. Rab- 

 bits may be immunized by injecting them repeatedly with 

 sterilized bouillon cultures. 



Resistance. This organism is destroyed in bouillon at 

 58 C. in ten minutes. A temperature of 56 C. for this time 

 did not destroy its vitality. They can not stand drying. The 



