DISSOCIATION AND TRANSFORMATION 175 



to earlier experiments on the development of B and C modifica- 

 tions. During animal passage of short duration, the changes were 

 less marked, since the authors reported only a transient loss of 

 virulence. Berger and Englemann 101 in the next year reported the 

 mutation of a strain of Type III Pneumococcus through the in- 

 termediary A modification to a green streptococcus. As in their 

 former experiments, the agents necessary for the transformation 

 were dry yeast-broth and serum-broth containing one five-thou- 

 sandth part optochin. Wirth 1523 believed that Streptococcus mu- 

 cosas represented a mutation from Pneumococcus, but he failed in 

 his attempts to prove it. 



In yet another paper Berger with Silberstein 103 described the 

 inulin-fermentative power of the variants. The results are difficult 

 to understand. Of ten strains of pneumococci, four showed merely 

 a reddening of the inulin medium without coagulation, while two 

 failed to display any action on inulin. The authors then classed 

 the latter strains when tested with optochin with Modification A. 

 Of the cultures of Modification B, obtained from pneumococci, but 

 otherwise behaving as green streptococci, two retained the ability 

 to ferment the carbohydrate. The strains were comparable in their 

 behavior toward inulin to some thirty viridans strains. Of the lat- 

 ter, five exhibited a marked action on inulin, and four others gave 

 slightly positive reactions. 



Reimann, 1127 repeating the experiments of Morgenroth, Schnit- 

 zer, and Berger, claimed, however, that the R cultures so derived 

 were still pneumococci, since the strains were bile-soluble and 

 autolyzed with greater readiness than did streptococci. The immu- 

 nological reactions of the variant pneumococci derived by Morgen- 

 roth's method, moreover, were identical with those of R pneumo- 

 cocci derived by various other means. When one considers the 

 atypical action of the Berger strains on inulin and the author's 

 omission of serological tests, one is inclined to accept Reimann's 

 interpretation as the correct one. 



Heim and Schlirf, 633 likewise, were unable to verify the work of 



