238 APPLIED BACTEEIOLOGY 



tions, and in the vinous fermentation it usually succeeds the 

 Sacch. apiculatus. It is classed as a 'wild' yeast, the spores 

 of which frequently occur in the atmosphere of breweries. 

 The Sacch. pastorianus is one of the yeasts causing 

 ' disease ' of beer, to which it gives an unpleasant, bitter 

 taste. 



Saccharomyces Mycoderma. — The cells of this yeast are 

 oval, elliptical, or cylindrical, 6 to 7 /a long and 2 to 3 /* 

 thick, united in freely-branching chains. Spore-forming 

 cells may reach 20 /j, long. One to four spores in each 

 mother-cell. This yeast forms the skin or ' mould ' on the 

 surface of fermented liquids, without, however, exciting 

 fermentation. When forced to grow submerged in a sac- 

 charine liquid, it gives rise to a small quantity of alcohol, 

 but no growth takes place. 



Saccharomyces Conglomeratus. — Forms cells, which are 

 round and united in clusters, consisting of numerous cells 

 produced by budding from one or more mother-cells. 

 There are two to four spores in each mother- cell. This 

 yeast occurs on rotting grapes and in wine at the com- 

 mencement of the fermentation. 



Saccharomyces Minor. — Occurs in oval or spherical cells 

 6 /J, in diameter, arranged in chains of 6 to 9 elements. 

 The spore-forming cells are larger (7_to 8"5 /j,), and contain 

 from two to four spores 3*5 fj, in diameter. This yeast 

 is stated by Engel to be identical with that employed by 

 bakers to ferment bread. 



Saccharomyces Exiguus. — Conical or top-shaped cells 5 /x 

 long, and reaching 2"5 fi in thickness, in slightly branching 

 colonies. There are two to three spores in a row in each 

 mother-cell. This yeast is often present in the after- 

 fermentation of beer. 



Torulae. — The term torula has been used both by Pasteur 

 and Hansen to denote a number of organisms closely re- 

 lated to the saccharomycetes in their form and mode of 



