402 MICRO-ORGANISMS AND FERMENTATION. 



butter. It occurred several times in cases of preserved butter, 

 and contains a fat-cleaving enzyme. Adametz has observed 

 a Torula during the blistering of cheese, and it was also 

 discovered by Bochiccio in Lombardy Grana cheese. The 

 Lactomyces inftans caseigrana alluded to above brings about 

 a marked blistering on the outer parts of hard cheese. It 

 coagulates sterile milk, and partially liquefies the coagulum 

 without noticeable formation of acid. It must, therefore, 

 contain a clotting enzyme and a tryptic enzyme. 



Saccharomyces apiculatus Reess. (Fig. 96.) 



According to our present views, the name of this ferment is 

 incorrect, for only those budding-fungi which yield endogenous 

 spores are considered to belong to the Saccharomycetes, and the 

 fungus in question does not possess this property. We will, 

 however, provisionally retain the old generic name, as has been 

 done by Hansen, until systematic classification has been further 

 developed. 



This ferment was the subject of one of the finest and most 

 thorough biological investigations of our time, for Hansen was 

 enabled, after several years' work, to determine both its habitat 

 in nature and its regular migrations at different seasons of 

 the year (p. 272). The reason why this species was selected for 

 the investigation was that, while other species occur in very 

 varied and uncertain forms, making the study of their occur- 

 rence in different localities very difficult, this ferment can be 

 recognised with certainty, for it always occurs in cultures 

 with lemon-shaped cells ; this is the typical form of the species. 



S. apiculatus occurs abundantly in wine fermentation, 

 especially during the early stages, and also in spontaneously- 

 fermented Belgian beer (Lambic, Faro, Mars, Krieckenbier), 

 and, according to van Laer, imparts to it its peculiar taste 

 and odour. In nature it is found on ripe, sweet, succulent 

 fruits. 



If a little of such a growth is examined under the micro- 

 scope in a drop of nutritive liquid, the development of the 

 fungus can be followed. This is very characteristic (compare 

 Fig. 96). It is seen that the buds formed from the typical 



