SCHIZOSACCHAROMYCETACE^. 293 



and will also develop on nutrient meat-broth gelatin, but grows 

 very badly in nutrient liquids. It was discovered in hazel-nuts 

 in Italy. 



281. The Family Schizosaeeharomycetaeese. 



The species of this family are monocellular fungi, which re- 

 produce by fission, and exhibit endosporogenation. The fission 

 of a cell is preceded by the formation of a septum, which at once 

 commences to divide into two lamellae from the outside. No 

 budding occurs. Each cell may be sporogenic. The spores are 

 monocellular, and 1-8 are formed in the parent cell. At present 

 the family comprises only a single genus, viz. : 



Schizosaccharomyces, P. LINDNER (XXX.), the generic charac- 

 teristics of which are also those of the whole family. In some 

 instances the formation of asci is preceded by fusion. All the three 

 species known at present produce spores which are stained blue by a 

 solution of iodine in potassium iodide (see p. 147, vol. ii.). The 

 species excite alcoholic fermentation in various sugar solutions. 

 According to Guilliermond the cells never contain glycogeu, in 

 which respect they present a contrast to those of the Saccharo- 

 mycetacece. 



Schizosaccharomyces Ponibe, LINDNER (XXX.), has been drawn 

 by the last named. The cells are cylindrical, 5-9 /j. long and 4-9 jj. 

 broad, but the dimensions fluctuate considerably. As a rule the 

 two ends of each cell differ in appearance, the one being rounded, 

 the other surrounded by a sharply defined ring embracing the 

 newly formed membrane, which already assumes a conical shape. 

 Hammer-shaped cells are not infrequently observed. The cells 

 are shorter in exhausted media. With restricted admission of 

 air many of the cells develop into long tubes, containing numerous 

 septa without, however, undergoing separation, and even when 

 the latter occurs, the cells frequently remain attached at one 

 point, as though hinged. According to GUILLIERMOND (II.), the 

 formation of asci is preceded by the fusion of two cells, which may 

 be sister cells, and he also observed instances in which fusion be- 

 tween three cells took place. Sporulation readily appears, even 

 in hanging wort drops, the spores forming sometimes in seven 

 days. Spores are also found in the sedimental yeast at the close 

 of primary fermentation. 1-4 lustrous spores, measuring about 

 4 IJL, are formed in a cell, and these begin to germinate by swelling 

 up to form an ascus, the spore membrane fusing into the new 

 integument without bursting. As soon as the ascus has attained 

 a length about equal to that of an ordinary vegetative cell, it 

 develops a septum and splits into two halves. No formation of 

 film takes place. At high temperatures the fermentation in beer 

 wort is of top-fermentation character. The species ferments 

 dextrose, maltose, and saccharose, and, in addition, Isevulose, inulin, 



