NATURE OF BACTERIOLYSANTS 



499 



STUDY OF THE COLONIES OF NORMAL STRAINS OF BACT. DYSEN- 



TERIAE (fLEXNER) 



In sixteen out of twenty agar subcultures of four old laboratory 

 strains of normal Flexner bacilli as well as in three out of eighteen 

 agar subcultures of twelve freshly isolated strains of normal 

 Flexner bacilli, I have noted one or more colonies with irregular 



TABLE 13 

 liaclerioli/tic aclivily of fdlrates of peptone water, cultures of normal dysentery 



bacilli (Flexner) 



* Colonies with irregular edges that are sometimes present in subcultures of 

 normal strains. 



edges among the mass of regular, round, typical, dysentery 

 colonies (table 12). These colonies were not as "irregular" 

 and "moth eaten" as those which were noted in subcultures of 

 "sensitive" strains but nevertheless resembled them. Successive 



