ALCOHOLIC FERMENTS. 



149 



parasite to the other. The amalgamation of the spores is, 

 perhaps, the beginning of the process. 



The germination of the spores of those species of the groups 

 Saccharomyces Pastorianus and Sacch. ellipsoideus which have 

 been examined, takes place in essentially the same way as that 

 just described. 



A second and quite different type occurs in the case of 

 Sacch. Ludwigii (Fig. 40), where the fusion takes place in the 

 very first stages of germination ; in this case, however, it is the 

 new formations and not the spores which grow together. These 

 new formations are further distinguished from the previous 

 type in that they are not yeast-cells, but mycelium-like 

 growths, -promycelium. The development of yeast-cells takes 

 place from this promycclium, a sharp partition wall being first 

 formed ; the cell is then detached, and its ends are finally 

 rounded. At the ends of these cells buds are developed, and 

 these also split off at the partition walls. 



In the case of the older spores this curious fusion is more 



FIG 41. Saccharomyces Ludwigii (after HANSEN) : germinating spores from old 

 gypsum-block cultures; at a and b each spore has developed a germ-filament; at c 

 are shown different forms produced by fusion. 



uncommon (Fig. 41). Some germ-filaments develop into a 

 branched mycelium (group b). 



The third type which occurs in Saccharomyces anomalies 

 (Fig. 42, see also description of the species), is distinguished 

 from the former in that the spores are of quite a different 

 shape, resembling the spores of Endomyces decipiens. 1 They 

 are almost semi-spherical with a rim round the base. 



*A fungus which is parasitic on the lamellae of certain mushrooms. 



