NATURE OF THE BACTERIOPHAGE 147 



reject this explanation, for such a substance would be rapidly 

 eliminated in the successive dilutions during repeated transfers. 

 It is thus useless to discuss this further. Up to the present time 

 no one has recommended this. 



2. The active principle derived from the organism reacting 

 against the infection is particulate, an organic being, capable of 

 developing afterward outside of the organism at the expense of 

 the bacteria. 



This hypothesis does not constitute a scientific heresy, for it 

 is not contradicted by any experimental fact. In the case of 

 any hypothesis, however improbable it may appear in view of the 

 actual state of biologic science, if it can not be experimentally 

 demonstrated false and if it harmonizes with the demonstrated 

 facts, it can not be rejected a priori. Moreover, Carrel has shown 

 that it is possible to cultivate tissues outside of the organism; 

 and in addition, Altmann has proposed a theory according to 

 which the zymogenic granulations can be nothing but bioplasts, 

 independent elements, having their individual existence and 

 capable of reproduction by division in a cellular medium. The 

 bacteriophage may be a bioplast, derived from the superior organ- 

 ism, and capable of multiplication at the expense of the bacteria. 



However this may be, since this particle, this "organite," 

 comports itself from the time when it is taken from the organism 

 as an autonomous being capable of assimilation and reproduction, 

 and since it acts as a being corresponding to the definition of a 

 microbe, it must be a minute being endowed with life. We will 

 revert to this idea in the case of the third hypothesis. 



Second hypothesis 



The bacteriophage may be derived from the lysed bacterium 

 itself. 



The two subsidiary hypotheses given above may again be 

 formulated: 1. The bacteria secrete a diastase with autolytic 

 functions. As we will see, this is in effect the conception of 

 Kabeshima. Bordet takes over this hypothesis with an added 

 complication, since he explains the origin of the principle in terms 

 of the first hypothesis, that is, a substance derived from the or- 

 ganism, and explains the continuity in series by means of the 



