490 WILSURT C. DAVISON 



an active bacteriolysant was obtained from the stool of a patient 

 the day before his death. One cannot at present predict which 

 organisms will be attacked by anj' given filtrate, nor explain 

 why certain cultures are readUy lysed while others are unaffected. 

 The bacteriolytic activity of a bacteriolysant may or may not be 

 increased by passage through live dysentery cultures but it is 

 decreased by passage through sterile peptone water and dead 

 dysentery bacilh. Contamination and refiltration may increase 

 or decrease the potency of a filtrate. Heating to 60 to 67°C. 

 for forty-five to sixty minutes has Uttle or no effect upon the act- 

 ivity of a filtrate. Bacteriolysants produce lysis more completely 

 in low dilutions and at a pH of 8.0 and 8.2. SaUne and peptone 

 water suspensions of Flexner bacilli at pH 8 were equally lys- 

 able. Young cultures are lysed more readily than older ones. 

 The addition of 1 cc. of N sodium hydroxide to 4 cc. of a bac- 

 teriolysant destroyed its bacteriolytic activity. Bacteriolysants 

 were non-pathogenic for a rabbit and as I have previously 

 reported (Davison, 1922b) had no therapeutic effect when 

 administered to twelve young children suffering from bacillary 

 dysentery. 



REFERENCES 



Davison, W. C. 1920 Divisions of the so-called Flexner group of dysentery 

 bacilli. Jour. Exper. Med., 32, 651-663. 



Davison, W. C. 1922a A summary of the literature and a complete bibliography 

 is given in Davison, W. C, Filterable "substance" antagonistic to 

 dysentery and other organisms (d'Herelle's phenomenon, bacterio- 

 phage, bacteriolytic agent, bacteriolysant, etc.). A bibliographic 

 review. Abstracts of Bacteriology (in press). 



Davison, W. C. 1922b The bacteriolysant therapy of bacillary dysentery in 

 children (therapeutic application of bacteriolj'sants — d'Herelle's 

 phenomenon). Amer. Jour. Dis. Child., 23, 531-534. 



