HYPOTHESES CONCERNING NATURE OF BACTERIOPHAGE 313 



material a principle causing the dissolution of dysentery bacilli 

 (d'Herelle33«). 



2. As for the theory offered by Bordet and Ciuca to explain serial 

 action, it is built up entirely on the dictum that, the "nutritive vitia- 

 tion" is "hereditary." The significance of such a statement is revealed 

 by the following facts. 



When a trace of a filtrate containing the bacteriophage principle is 

 added to a suspension of susceptible bacteria the bacteria are dissolved. 

 The limpid material thus formed is filtered through a porcelain candle 

 i7nper7neahle to bacteria. A trace of the filtrate so obtained, is intro- 

 duced into a second suspension containing only fresh normal bacteria, 

 and their dissolution follows. This second suspension, now that it in 

 turn has become limpid is filtered, and a trace of the filtrate is added to 

 a third suspension, again containing only normal bacteria. This 

 results in their dissolution. And this process can be continued in this 

 way, serially, for an indefinite period. 



Filtration through a porcelain candle intervening betw^een each pas- 

 sage renders it certain that, with the trace of filtrate, none of the bacteria 

 whatever of the suspension previously dissolved are passed on to the 

 suspension into which this trace of filtrate goes, to later produce dissolu- 

 tion. Since none of the bacteria of the suspension which was apparently 

 dissolved were transported into that which is next to undergo bacteri- 

 ophagy where is the opportunity for the transmission of an acquired 

 character? How can one invoke heredity when there are no descendents? 



How, then, can Bordet and Ciuca expect us to believe that an heredi- 

 tary character can be excreted in a soluble state, that this character can 

 be passed through a porcelain filter, that it can maintain itself in a fluid, 

 increasing and decreasing in potency, and that it can be communicated 

 to a healthy bacterium by simple contact with this liquid? I think that 

 it is needless to discuss such a theory which, although it has not been 

 exphcitly stated in these terms by Bordet and Ciuca, is the only one 

 to accord with experimental facts and observations, if, in spite of every- 

 thing, they would have us support the idea that the phenomenon of 

 bacteriophagy is caused by an hereditary nutritive vitiation of the 

 bacteria.* 



It has seemed wise to some authors to vary this theory somewhat. 

 Thus, Kuttner^^^ would derive the nutritive vitiation of the bacterium 



* Bordet seems to have abandoned his hypothesis. Others, Ciuca for exam- 

 ple, continue to support it, without, however, considering in any way the argu- 

 ments, such as are here presented, which were published in 1923. ^^^ 



