132 STUDIES ON FERMENTATION. 



specimens from the flasks A, B, C, at difierent times between 

 June and January, and that the microscope never revealed the 

 least trace of yeast in them. We may note besides that, during 

 this interval, we impregnated fresh flasks of wort with 

 specimens taken from the deposits in the flasks A, B, C, and 

 that we always obtained reproduction of the mucor and its 

 peculiar fermentation without the least appearance of ordinary 

 ferment. 



The inferences from the results that we have just detailed folio w 

 readily, and are besides of great interest. In the first place, it is 

 evident that even if the mucor mucedo may be able to produce 

 alcoholic fermentation, it is totally incapable of changing into 

 yeast. The two plants are necessarily and radically distinct, 

 and, if difierent authors have succeeded in obtaining them mixed 

 one with another in growths of mucor, this intermixture was 

 doubtless the result of a spontaneous sowing of the j^east, the 

 germs of which abound, particularly in the particles of dust 

 existing in the atmosphere of any laboratory in which studies 

 relating to fermentation are pursued. 



This, however, is not the most striking inference from the 

 facts which the cultivation of these organisms revealed. The 

 mucor is evidently a plant, at the same time aerobian and 

 anaerobian. If we had sown the spore-bearing filaments of 

 mucor on slices of pear, lemon, or similar fruit, we should 

 have seen the spores germinate, tubes of mycelium ramifying 

 on the surface of the substratum, and reproducing sporiferous 

 aerial hyphae. In this case the plant would have eflected all 

 its phenomena of nutrition by absorbing oxygen and emitting 

 carbonic acid, after the manner of animals, as, in our essay on 

 the organic corpuscles which exist in a state of suspension in 

 the atmosphere, we have shown to be the case generally with 

 fungoid growths. Under these circumstances, the only sugar 

 decomposed would have been a quantity equivalent to that 

 assimilated in forming the cellulose of the young tissues of 

 the fungus, or in entering into combination, either with the 

 elements of ammonia or with the sulphur of the sulphates, or 



