SECTION XIV. 



LIFE HISTORY AND VARIABILITY OF THE SACCHA- 

 ROMYCETES. CLASSIFICATION OF THE SACCHA- 

 ROMYCETES AND SCHIZOSACCHAROMYCETES. 

 BY ALBERT KLOCKER, COPENHAGEN. 



CHAPTER LIII. 



THE LIFE HISTORY OF SACCHAROMYCETES 

 IN NATURE. 



271. Fundamental Researches on the Life 

 History of Saccharomycetes. 



THE first of the yeast fungi whose cycle of existence was traced in 

 nature was the Saccharomyces apiculatus, more fully described in 

 chapter Ixi., the researches having been carried out by Hansen. 

 This small, lemon-shaped asporogenic alcohol yeast, which is 

 widespread in nature and generally known, received its name, 

 Sacch. apiculatus, from Reess. In the following lines the term 

 Saccharomycetes, whether used in a general sense or qualified by 

 the prefix " true," will be applied to alcohol yeasts capable of 

 producing endospores as well as of budding. As the researches in 

 connection with Sacch. apiculatus are typical of those concerned 

 with the life history of the true Saccharomycetes, a brief intro- 

 ductory resume of them will now be given. 



In the years 1880-1881 HANSEN (XXII. and IX.) published 

 the results of his investigations on the career of the yeast in 

 question. From these it appears that the chief habitat and breed- 

 ing-place of this fungus in the summer and autumn are damaged, 

 sweet, juicy fruits, in the juice of which it reproduces in great 

 abundance, whilst in winter and spring it inhabits the soil under- 

 neath fruit trees and bushes. From the fruit it finds its way into 

 the soil, either through the dropping of the fruit or the swilling 

 action of rain, as well as in the excrement of the numerous insects 

 that infest and devour the sweet, juicy fruit inhabited by the cells. 

 With regard to the means by which the minute cells are trans- 



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