RED YEASTS AND BLACK YEASTS. 403 



group now in question ; J. C. BAY (III.) contests their claim to 

 be considered Saccharomycetes. Some doubt also attaches to the 

 Saccharomyces japonicus and Sacch. keiskeana (seep. 240, vol. ii.) of 

 K. YABE (VI.). On the other hand, one of the species described 

 by K. GOLDEN and G. C. FERRIS (I.) is said to be identical with 

 Saccharomyces glutinis ; and another species has been allocated to 

 the Mycoderma group. 



From all the reports, which could be amplified without diffi- 

 culty, as to the occurrence of red- coloured budding fungi, it 

 appears that these organisms are very common. 



The arrangement of these diversified forms, the majority of 

 which have not yet been thoroughly examined, into a system is 

 still more difficult than in the case of the species comprised in the 

 generic name Torula. It is equally difficult to decide whether 

 certain of these forms are identical or not. 



On the basis of their special method of vegetative repro- 

 duction, one of the species described by Hansen, as well as the 

 Mycoderma rubrum and Mycoderma humuli of A . Lasche, the red 

 Torula of Janssens and Mertens, Koch's pink yeast (according to 

 P. Lindner), and the Blastoderma salmonicolor of Fischer and 

 Brebeck, may be arranged in one group. A second group might 

 include the forms with more or less globular cells, such as Saccharo- 

 myces glutinis, Colin, one of the species described by Hansen, and 

 several others. The latter, as producing the most pigment, might 

 be united with the firsb sub-group of the Torulacece t with which 

 they appear to have a good deal in common. 



The colour of the cells is usually noticeable only when a large 

 number are in juxtaposition. The shades of colour are numerous : 

 pale red, rose-red, vermilion, coral, yellowish red, and salmon-red. 

 Pigmentation seems dependent on certain conditions in many 

 species, and in some occurs very late, so that it is not a constant 

 feature. The intensity of the colour also varies, and is dependent, 

 inter alia, on the reaction of the nutrient medium. 



The cells vary in size and shape quite as much as with the 

 TvrulacecG. 



Like the Torulacece, too, highly refractive bodies that have 

 undoubtedly often been mistaken for spores, occur in the cells, 

 especially those of old cultures. In Janssens' and Mertens' red 

 Torula, the bodies of this kind observed in the vacuoles resembles 

 drops of oil, and are orange-coloured. They, however, consist 

 largely of carotin, but do not appear to contain fat. A uniform 

 reddish tinge is often visible in the vacuoles in old cultures of 

 Blastoderma salmonicolor. In other respects there is no infor- 

 mation available regarding the seat of the pigment in red budding 

 fungi. 



The nature of the pigment varies, being sometimes soluble 

 in water, and disappearing under the influence of acids and 

 alkalis ; whereas, on the other hand, the red Torula of Janseens 



