346 BACTERIOLOGY. 



greatest accumulation of toxin in bouillon is after a 

 duration of growth of the culture of from five to ten 

 days, according to the peculiarities of the culture em- 

 ployed. At a too early period toxin has not sufficiently 

 accumulated, at a too late period it has begun to de- 

 generate. In our experience the amount of muscle 

 sugar present in the meat makes no appreciable differ- 

 ence in the toxin produced, so long as the bouillon has 

 been made sufficiently alkaline to prevent the acid 

 produced by the fermentation of the sugar from pro- 

 ducing in the bouillon an acidity sufficient to inhibit the 

 growth of the bacilli. In neutral bouillon, as pointed 

 out by Smith and Spronck, the sugar does produce suffi- 

 cient acid to interfere with the growth of the bacilli 

 and the development of toxin. This can be prevented 

 by the previous destruction of the sugar through the 

 fermentation caused by the growth of the colon bacilli. 

 After the fermentation 0.1 per cent, of glucose should 

 be added. Beside the sugar and allied bodies in the 

 meat there are other substances, whose nature is un- 

 known, which hinder or aid a full growth of the bacilli 

 or production of toxin. This is true of bouillon made 

 directly from fresh meat, fermented meat, or meat ex- 

 tracts. With the meat as we obtain it in New York we 

 get better results with uufermented meat than with fer- 

 mented. In Boston, with the same bacillus, Smith 

 gets more toxin from the fermented bouillon. Con- 

 tradictory results have been obtained by others, and 

 must be attributed to the difference in the materials used. 

 Under the best conditions we can devise, toxin begins 

 to be produced by bacilli from some cultures when 

 freshly sown in bouillon some time during the first 

 twenty-four hours; from other cultures, for reasons not 



