( 57 ) 



CHAPTER II. 



SACCHAROMYCETES. 



The Saccharomycetes, or Yeast Fungi, are unicellular plants, 

 which multiply themselves by budding, and reproduce them- 

 selves by endogenous spores. They live singly or united in 

 bud-colonies, chiefly in saccharine solutions, where they excite 

 alcoholic fermentation. 



In most of the Saccharomycetes the cells are round, 

 oval, or elliptic ; seldom are they elongated into cylindrical 

 tubes, which are divided by transverse partitions, and may 

 be regarded as the first indication of the formation of 

 hyphae, i.e. of a mycelium. For the purpose of multiplica- 

 tion the cell forms an outgrowth, which is filled with a 

 portion of the contents* of the mother-cell, gradually assumes 

 the form and size of the latter, and separates itself from it 

 by a wall. Both cells can in like manner produce fresh 

 daughter-cells, which often remain for a considerable time 

 united with one another, and on separation continue to 

 grow independently. 



The formation of spores succeeds most easily on a 

 moist solid substratum. Typically the whole cell-contents 

 divide themselves into 2-4 roundish portions, or contract 

 into a single spherical body. The portions of the contents 



