176 BIOLOGY OF PNEUMOCOCCUS 



Morgenroth and his collaborators, yet Silberstein, 1286 who quoted 

 these authors, by the aid of optochin in vitro, claimed to have ex- 

 perienced no difficulty in carrying a Group IV pneumococcus 

 through the successive stages of Modification B (green Strepto- 

 coccus) to Modification C (virulent hemolytic Streptococcus) and 

 then from this form to a Type I pneumococcus of low virulence. 

 Paul 1070 was another to join the newer school which believed that 

 the gap between pneumococci and streptococci could be bridged by 

 these methods. He produced bile-insoluble dissociants and to him 

 they appeared to be indistinguishable from certain strains of 

 Streptococcus viridans. 



Gorander (1930) 542 also stated that he had transmuted cultures 

 of Streptococcus viridans into bacterial forms that in every re- 

 spect were identical with the type-specific pneumococci of human 

 origin, except that the strains were not agglutinated by antipneu- 

 mococcic serum. The defect would seem to be a vital one. The cul- 

 tural changes were accomplished by repeated cultivation on blood 

 agar and by short mouse passages. According to Gorander, after 

 the third short (four-hour) mouse passage, hemolytic streptococci 

 appeared. Following five twenty-four hour incubation periods in 

 mice, the organisms resembled pneumococci. The variants had cap- 

 sules, were soluble in sodium taurocholate, and were moderately 

 virulent for mice. The pneumococci so obtained, after repeated 

 growth of this passage culture in artificial media (alternating 

 bloou agar and broth), were retransformed "into a bacterium of 

 perfect Streptococcus viridans type." 



Gorander claimed further to have transformed Streptococcus 

 viridans and Type I and Type II pneumococci into forms which he 

 considered to be their original state, "since they were absolutely 

 equal culturally, biologically and serologically in all respects." 

 The homologous antiserum agglutinated both strains, and "the 

 bacteria absorbed not only their homologous but also heterologous 

 agglutinins from both sera." Gorander's further conclusions were 

 so heterodox that they are quoted here: 



