154 THE BACTERIOPHAGE 



Kabeshima, in 1920, starting on the one hand from considera- 

 tions without significance (as, for example, the thermal death 

 point of the bacteriophage, which he found to be too high to be 

 applied to living beings), and on the other hand, from inexact 

 experimental results (he announced, for example, that the bac- 

 teriophage resisted the action of alcohol; that it was active in the 

 presence of sodium fluoride, etc.), formulated the following 

 hypothesis. Under the action of a proferment playing the role 

 of a catalyzer, the autolytic diastases are activated and bring 

 about their dissolving action. 



We have already considered the principal objections which 

 render this hypothesis untenable. It fails to explain serial ac- 

 tion, for a proferment would disappear rapidly as a result of dilu- 

 tion in the course of passages; it does not take account of the fact 

 that the bacteriophage presents itself in the form of autonomous 

 particles capable of being counted; it is formally contradicted 

 by the fact that the same bacteriophage can act on diverse bac- 

 terial species, etc. The inadmissibility of the hypothesis of 

 Kabeshima has been recognized, moreover, by all authors who 

 have considered the question. 



KEFUTATION OF THE HYPOTHESIS OF BORDET AND CIUCA 



Bordet and Ciuca (October, 1920) very significantly modified 

 the hypothesis of Kabeshima to the end of explaining serial 

 activity. They said: 



"In view of the fact that the stools of patients with dysentery are rich in 

 leucocytes, and that the lysinogenic power is only observed toward the 

 period of convalescence, we have asked ourselves if the phenomenon of 

 d'Herelle is not the result of a defensive activity of the organism, and 

 particularly of an activity of the leucocytic exudate. This produces in 

 the bacterium an hereditary nutritive vitiation, consisting in the produc- 

 tion by the bacterium of a sort of lytic ferment, which is capable, moreover, 

 of diffusing in the ambient fluid and as a result, reacting in the same fashion 

 on normal bacteria of the same species." 



This proposition takes no account of the previously established 

 facts. Among other facts it disregards that I had made it known 

 some time previously that the bacteriophage was a normal in- 

 habitant of the intestine, and that lysogenic power was also to 



