130 STUDY AND IDENTIFICATION OF BACTERIA 



hence, this experiment would be impossible with them, as upon heating we should 

 first destroy the toxin. 



On account of the frequent association of B. pyocyaneus with other 

 organisms of better recognized pathogenicity it has until more recently 

 been considered rather harmless; this view can no longer be entertained 

 as it is frequently the sole cause of middle-ear inflammations, intestinal 

 disorders, cystitis and possibly at times of septicaemia. 



B. Prodigiosus. This is a very small coccobacillus which shows mo- 

 tility in young bouillon cultures. It is Gram-negative. The colonies 

 on agar or other solid media show a rich red color. The pigment only 



FIG. 36. Bacillus pyocyaneus. (Kolle and Wassermann.) 



develops at room temperature, it is absent in cultures taken out of the 

 incubator. The B. prodigiosus is frequently found on foodstuffs, espe- 

 cially bread, where it may simulate blood. It liquefies gelatin rapidly 

 and gives a diffuse turbidity to bouillon. It is probable that B. indicus 

 and B. kilensis are strains of B. prodigiosus. 



Coley's fluid, which has been used in cases of inoperable sarcoma and other 

 malignant growths, is a culture prepared by growing very virulent streptococci in 

 bouillon for ten days. This Streptococcus culture is now inoculated with B. prodi- 

 giosus, and after another ten days the mixed culture is killed by heat at 60 C. and 

 the sterile product injected. Coley injected about J^o c.c. of this vaccine. At 

 present he uses nonfiltered, heat sterilized bouillon cultures of a Streptococcus 

 obtained either from a case of erysipelas or septicaemia. To this is added material 

 from agar cultures of B. prodigiosus, grown separately and sterilized before adding 

 to the sterilized streptococcus bouillon culture. 



