282 THE BACILLUS OF BLUE PUS 



also be sown in broth with blood and scrapings of tissues. The characteristic 

 colour produced by the bacillus is sometimes only apparent after several sub- 

 cultures in broth or on agar. 



Inoculations should be made into the peritoneal cavity of a guinea-pig 

 or into the ear vein of a rabbit. 



Besson isolated the organism from water by sowing in MetchnikofFs gelatin - 

 peptone-salt medium (p. 33). When growth appeared after 1215 hours a sub- 

 culture was made in the same medium, and a trace of this second culture was sown on 

 gelatin plates from which the organism was easily obtained in pure culture. 



