PRODUCED BY ALCOHOLIC FERMENTS. 217 



contact with the juice in which Sacch. apiculatus has developed, 

 considerable quantities of the yeast often stick to their hairy 

 coverings, where it slowly dries. The cells, as my experiments 

 have proved, can keep alive for a longer period in this manner 

 than when they are dispersed in atmospheric dust In the 

 latter case the drying up will, as a rule, have a more destruc- 

 tive effect. 



These were the results of my studies mentioned above. 

 The sweet succulent fruits of the garden proved to be the 

 normal place of development of the small yeast ftingus, and the 

 soil its normal winter habitat* My experiments have thus 

 shown that insects and other small animals are active in 

 distributing the cells of this yeast, but that the wind also 

 plays a highly important part. This latter means of transport 

 especially demands the attention of brewers in connection 

 with the question of micro-organisms. 



Sacch. apiculatus is as yet the only species of yeast whose 

 migrations in nature are known. My experiments on the 

 true Saccharomycetes (yeasts exhibiting endospore-formation, 

 a character not possessed by Sacch. apiculatus) in connection 

 with this question have not yet led to a successful issue. Our 

 knowledge of the most important species relating to the 

 fermentation industry is in this respect still very imperfect. 

 The investigators who first studied yeast cells, observed 

 that these occurred on sweet succulent fruits, especially on 

 those which were damaged, and that they multiplied there. 

 My numerous experiments have also confirmed the fact that 

 this occurrence is very general ; fallen fruits especially give 

 rise to a luxuriant growth. With regard to the wine yeasts, 

 according to Pasteur's view, these do not pass the winter in 

 the soil. My experiments are, however, opposed to this view. 

 I have, in fact, found these yeasts alive in the soil under vines 



* I published some recent investigations on Sacch. apiculatus in ' Botanisches 

 Centralblalt,' Bd. 21, No. 6, 1885, in 'Annales des sciences naturelles. Botanique,' 

 t. ii. No. 3, 1890, and in ' Annales de microgvaphie,' 1890. 



