380 



MICRO-ORGANISMS AND FERMENTATION. 



Schizosaccharomyces (Sacch.) Pombe was discovered by 

 Saare and Zeidler in millet beer from Africa, and more exactly 

 described by Lindner. It is closely allied to the previous 

 species ; its propagation also takes place by formation of 

 partition-walls and by fission ; frequently the two new cells 

 remain connected for some time at a single point, upon which 

 they rotate until they form an acute angle to each other. 

 The cells resemble the conidia of Oidium ; but the shape of 

 many of them is suggestive of the manner in which they were 

 derived, one end being rounded, whilst the other is surrounded 

 by a well-defined ring- wall, enclosing the newly-formed piece 

 of globular membrane. In the cells one to four spores may 

 occur, which grow in the same way as those of S. Ludwigii 

 viz., by the formation of a germinative thread no fusion of the 

 promycelium of the spores has been observed. 



Guilliermond has closely examined the course of spore- 

 formation, and finds that the ascus-formation often follows 

 a fusion of two cells which may be sister cells. In this way 

 the dumb-bell shaped cells often met with in spore-cultures 

 are formed. He also observed a fusion of three cells. Spores 

 also form in the sedimentary yeast. By germination they 

 swell up and form a germinal tube, which afterwards divides 

 into two cells by means of a septum. 



The growth forms no film on wort. On wort-gelatine it 

 forms a compact finely-furrowed growth. 



At its optimum temperature, 30 to 35 C., this species 

 shows high-fermentation phenomena. It is distinguished by 

 the considerable amount of acid formed during the fermenta- 

 tion, and possesses a certain power of resistance in competition 

 with bacteria. In beer-wort it gives a rather vigorous fer- 

 mentation ; it also produces fermentation in dextrose, maltose, 

 and cane-sugar solutions. It does not ferment d-mannose, 

 but does ferment dextrin. 



According to Rothenbach's experiments, it ferments about 

 half the total amount of diastase-dextrin prepared according 

 to Lintner's directions, leaving achroo-dextrin, which, on 

 addition of alcohol, slowly separates out in sphaero-crystals. 



As this species is capable of forming very considerable 

 amounts of alcohol, it might be supposed to be of industrial 



