150 STUDIES ON FERMENTATION. 



examples of this fact in the present paragraph. A German 

 naturalist, Dr. Rees, who has discovered new proofs of the 

 diversity of alcoholic ferments, putting aside, perhaps rightly, 

 such scruples, has attached specific names to the different kinds 

 of ferments, in his brochure published in 1870, which we have 

 already cited (p. 71). Indeed, we have often ourselves, for 

 brevity's sake, made use of the names proposed by Dr. Rees.* 



In a Note inserted in the Bulletin de la SociefS chimique de 

 Paris, in 1862, we figured a ferment of small dimensions, 

 which develops spontaneously in must, filtered or unfiltered, 

 and which is very different from the ordinary ferment of wine. 

 It is the first to make its appearance in the fermentation of the 

 grape, and may even appear alone if the must has been pre- 

 viously well filtered, doubtless because its germs, being smaller 

 than those of other ferments, pass through the filter more 

 easily and in greater number. Fig. 27, extracted from our 



o 



Fig. 27. 



Note of 1862, represents this ferment, together with some 

 spherical cells of high yeast, with the object of giving a more 

 exact idea of the relative dimensions of these two ferments 

 and their dissimilarities. Dr. Rees has named it saccharomyces 

 apiculatus. 



* The principal result of Dr. Eees' labours consists in the discovery of 

 a sponilation peculiar to yeast cells, that is to say, to a formation in the 

 interior of these cells, and under particular conditions — such as when 

 the growth occurs on slices of cooked potatoes, carrots, &c. — of two, 

 three, or four smaller cells, which, when placed in fermentable liquids, 

 act like the germinating spores of ferments. The mother-cell may be 

 regarded as an ascus, and the daughter-cells as ascospores, and so the 

 genus sncchnromyces may be classified among the group of fungi termed 

 ascomycetes. These facts have been frequently confirmed, notably by 



