120 



STUDIES ON FERMENTATION. 



conditions under which each of the experiments was conducted 

 had been as similar as could be. 



We were at a loss to account for this inactivity in the cells 

 of the mycoderma. Even in the most favourable cases of the sup- 

 posed fermentation, it was evident that a host of cells of 

 mycoderma vini did not become cells of yeast ; but how could it 

 possibly be admitted that amongst the millions of submerged 

 cells, none were adapted for transformation, if that transforma- 

 tion were at all possible ? 



Thereupon, to find a way out of the difficulty, we resolved to 

 modify completely the conditions of our experiments, and to 

 apply to the research that we had in view a mode of cultivation 

 that might completely, or nearly so, obviate the sole cause of error 

 that WG suspected, namely, the possible fall of cells or germs of 

 yeast during the manipulations. We secured this by the use 

 of flasks with two tubes, the right hand one of which was closed 

 by means of a piece of india-rubber tubing with a glass stopper, 

 the other one being drawn out in the shape of a swan's neck. 

 The use of these flasks, which was then new to us, permitted us to 

 grow mycoderma and to study it under the microscope without 

 fear of disturbance from exterior particles of dust. This time we 

 obtained the results given in the first part of this paragraph. 

 We no longer observed yeast or alcoholic fermentation following 

 the submersion of the efilorescence, either in the flasks them- 

 selves, or in the test-flasks attached to them, as represented in 

 Fig. 19. We observed, however, that kind of alcoholic fer- 

 mentation of which we have already spoken and which is due 

 to the raj'coderma itself, a fermentative action that is still more 

 instructive than the one which we thought we had determined, 

 and certainly not less calculated to support the theory of 

 fermentation which we have already briefly sketched. 



In an age when ideas involving transformation of species are 

 so readily accepted, perhaps in consequence of their requiring 

 no rigorous experimental work, it is not without interest to 

 consider that, in the course of our researches upon the growths 

 of microscopic plants in a state of purity, we once were 



