AZROBIC LIFE AND ANAEROBIC LIFE 79 



VII 



AEROBIC LIFE AND ANAEROBIC LIFE 



And Pasteur, in all the enthusiasm of his discovery, 

 adds or did add soon: It is not simply for alcoholic 

 fermentation that this is true. I can return now to 

 affirmations respecting the lactic fermentation, which 

 it is very easy to start in a purely mineral medium. 

 The lactic ferment is smaller and in appearance simpler 

 than the alcoholic ferment. It is a little cell constricted 

 in the middle (2, Fig. 8) and the whole interior of which 

 is filled with a mass that appears to be homogeneous, 

 whereas it is differentiated in the yeasts. But the needs 

 of this little cell are not less: they are different, that is 

 all. These two dissimilar ferments are, moreover, 

 specific, that is to say the alcoholic ferment does not 

 produce lactic acid, contrary to what is generally be- 

 lieved and taught, and the lactic ferment does not yield 

 alcohol when it is alone and unmixed with the alcoholic 

 ferment. 



Do not believe, furthermore, with Boutron and Fre'my, 

 that successive fermentations can take place in the same 

 medium with or without order, according to the mode 

 and progress of the decomposition of the nitrogenous 

 substance. That happens when your spoiled meat or 

 rotted cheese carries with it into the fermentation flask 

 the numerous organisms which ordinarily populate it: 

 it does not happen when you grow a pure ferment in 

 clear nutrient bouillons. You are told that the butyric 

 fermentation, the mannitic, etc., accompany or follow 

 lactic fermentation. It is not so, everything stops in 

 my flasks when all the sugar is transformed into lactic 

 acid, now become lactate of lime by contact with car- 

 bonate of lime introduced into the liquid. 



