232 



THE BACTERIOPHAGE 



disturbances lasting some hours. The first time there was no 

 obvious cause; the second attack followed a suspected meal taken 

 in a village tavern. On each occasion specimens of the stools 

 were examined on the following days. The results are recorded 

 in table 2. 



There can be no doubt that in the first case the cause was 

 B. dysenteriae Flexner, and in the second B. paratyphosus B. 

 Disease was aborted, the bacteriophage having quickly acquired 

 virulence for the invading germ. 



TABLE 2 



We will complete this section by giving the results of tests 

 made on the stools of three normal persons (aged 39, 22, and 17 

 years) during the period of the 15th to the 30th of July. Only 

 the bacteria against which the bacteriophage showed a virulence 

 in each of the three persons designated by the numbers I, II, and 

 III, are recorded (table 3). 



It is unnecessary to multiply examples. All of the experi- 

 ments which have been conducted have given comparable results. 

 One conclusion stands out; the bacteriophage is a normal in- 

 habitant of the human intestinal canal. 



