184 THE BACTEEIOPHAGE 



was lysed after about a dozen transplantations. It was, then, a 

 bacillus which was refractory to the bacteriophage when taken 

 from the body. 



At the same time a strain of bacteriophage was isolated from 

 the stools of the patient. This presented the following virulences: 

 Shiga 0, Flexner + + ; stock culture strain of Hiss + + + + ; 

 B. coli + ; the Hiss strain from the patient +. After twelve sub- 

 cultures of the Hiss strain from the patient the virulence of the 

 filtrate was again tested. Perfect lysis was secured, showing 

 that the bacillus had lost its resistance by transfers on agar. 



The bacteriophage of the patient is active to a maximum degree 

 against a stock strain of the Hiss bacillus but it is only slightly 

 active for the individual strain causing the infection, with which 

 it forms, in vitro, mixed cultures indefinitely cultivable. There 

 was likewise in the intestine of the patient a mixed culture of 

 the bacteriophage and the refractory Hiss strain. 



In spite of every care and repeated injections of anti-dysentery 

 serum the patient became more and more weak; the temperature 

 oscillated between 38 in the morning and 40C. in the evening; 

 the number of stools gradually increased and became uncountable 

 on about the thirtieth day; and at about this time the patient 

 fell into a marasmic condition, the temperature stayed at about 

 38C. and death occurred on the thirty-fifth day. 



Bacteriologically, the stools, tested each day, showed an al- 

 most constant bacterial flora. The pathogenic bacillus was always 

 abundant, often in almost pure culture, and presented the char- 

 acteristics described. The virulence of the bacteriophage in- 

 creased continuously until the fifteenth day when it became fixed, 

 showing: Shiga + + + + ; Flexner + + + + ; Hiss + + ++, 

 B. typhosus + + + ; B. paratyphosus A + + + ; B. paratyphosus B 

 + + + ; B. coli + + + + ; bacillus of the patient (completely 

 refractory) when freshly isolated, + -f- + after fifteen transplants. 



At autopsy 3 there was isolated from the contents of the colon, 

 from a fragment of mucous ulceration, from the liver, from the 

 spleen, and from the heart blood, a Hiss dysentery bacillus, pre- 

 senting the same characteristics as that which had been isolated 



3 Performed by L. Ge"ry, whom I thank for the specimens he was kind 

 enough to send me. 



