STUDIES ON FERMENTATION. 77 



rairiute spherical cells reproducing the form shown in Nos. I. 

 and II. 



The forms figured in No. III. represent one of the types of 

 mycoderma vini, which is often found in this branching arbor- 

 escent state ; but it frequently also occurs in short forms, and it is 

 in this shape that it is generally met with on the surface of wines. 



It is true that the nature of the substratum has a great 

 influence on the changes of aspect in the organisms which we 

 are describing, but this is not the sole cause of their morpho- 

 logical modifications. We are strongly inclined to believe that 

 each of the cells, or vegetating forms so represented, difiering so 

 greatly as they do in aspect, and begotten, all of them, spon- 

 taneously in certain appropriate liquids, in a laboratory where 

 researches on fermentation are pursued, is capable of furnishing 

 a distinct variety. In fact, there is not a single one of the 

 cells in the six varieties in Fig. 12, which, taken alone, has not 

 its own peculiar characteristics, which, by hereditary trans- 

 mission, it can impart, in a greater or less degree, to all the 

 individuals of the generations that succeed it. 



We may remark, on the other hand, that nothing can be 

 more favourable to the isolation of different varieties of toruJa 

 or mycoderma vini than the spontaneous impregnations to which 

 we submit our liquids. For when suitable liquids contained in 

 flasks exhausted of air are impregnated with the particles of 

 atmospheric dust, by opening the flasks for a moment and then 

 immediately re-sealing them, it must generally happen that we 

 admit only one species of reproductive organism, so that we 

 shall have a vegetation exclusively of one kind, as being derived 

 from the same mother-cell. If we could take from a crowd 

 composed of men and women separate couples, and forthwith 

 transport each couple to a separate isolated and unpeopled 

 island, they would, in the course of time, beyond doubt form so 

 many distinct tribes. 



It is very remarkable that some of the torulce in Fig. 12 are 

 not ferments ; they do not cause sugar to decompose into 

 alcohol and carbonic acid, any more than the mycoderma viioi 



