178 BACTERIOLOGY. 



a representative of the genus Plectridium. In 

 the vegetative stage the rods often elongate into 

 filaments ; they stain by Gram's method. In 

 gelatin stab-cultures, delicate branches, like 

 those of a fir-tree, grow out from the inoculation 

 line into the gelatin ; this appearance is less 

 marked in agar. In glucose-bouillon, vigorous 

 gas-production takes place accompanied by a 

 pronounced turbidity which clears gradually, a 

 deposit settling to the bottom. The gelatin is 

 slowly liquefied by an enzymotic action. The 

 bacteria are anaerobic and in cultures develop 

 a repulsive odor. Growth can take place be- 

 tween i5-42 ; spore formation can occur 

 within the same temperature limits, but at the 

 room temperature the rod-forms may persist 

 for at least a week without forming spores. 

 The vegetative cells grow poorly above 42 and 

 perish at 60, while the spores are very resistant 

 and withstand the action of both heat and 

 chemicals. 



, Only cultures mixed with other organisms 

 cause subcutaneous suppuration ; the pure 

 cultures are unable to do this. Perfectly pure 

 cultures were first obtained by Kitasato through 

 the application of a method based on the resist- 

 ance of the spores to heat, and by Kitt through 

 anaerobiotic methods. A powerful poison, in 

 all likelihood of a proteid character, is formed in 



