YEASTS 



139 



Belonging to the suborder Gymnoascees we have i. the family of Saccharomyce- 

 tidas, which reproduce by budding and in which the asci are without any semblance 

 of a sheath, and 2. a family in which there is an indication of the formation of a peri- 

 thecium this may be termed the Gymnoascidae family. 



SACCHAROMYCETID.E. There are three genera: Saccharomyces, Endomyces, and 

 Cryptococcus. 



Saccharomyces. These reproduce by budding, have ascopores and no mycelial- 

 like threads. 



S. eeremsia. This is the ordinary yeast fungus. Used at times as an antiseptic. 

 It is also used in treatment of beriberi as it is very rich in vitamines. 

 S. angina. Found in a case of angina. 



S. blanchardi. Found in a jelly-like tumor mass of the abdomen. The budding 

 cells varied from 2 to 20^1. Probably identical with S. tumefaciens, reported 

 as the cause of a subcutaneous tumor about region of Scarpa's triangle. 

 Endomyces. Forms spores in the interior of filaments, or by ascus formation or by 

 chlamydospores (resistant spore-like structures with a thick membrane which 

 project from the extremities or sides of the hyphae as bud-like structures). 

 E. vuillemini. One of the organisms of thrush. It produces a false membrane, 

 especially on buccal surfaces, which is easily detached and beneath which the 

 mucosa is intact. Grows only in acid media. Hence propriety of alkaline 

 treatment. Some authorities consider the genus Endomyces as the same as 

 Monilia or Oidium. 



Cryptococcus. Reproduces by budding, but ascospore formation not observed. 

 Not a well-recognized genus. The diseases caused by it are termed blasto- 

 mycoses. 



C. gilchristi. The cells are about i6ju in diameter and have a thick, double con- 

 toured membrane. They reproduce by budding. The skin lesions resemble 

 various infectious granulomata and diagnosis rests on the finding of budding 

 or sporulating cells. It may invade internal organs. Original cultures are 

 obtained with some difficulty and then best with Lender's serum. Subcultures 

 grow readily. Potato is a good medium and on it we may have both mycelial 

 and yeast-like growth. Guinea-pigs can be inoculated subcutaneously. A mould, 

 somewhat similar, is the Coccidioides immitis of Ophuls. This has a mycelial 

 growth in tissues, this distinguishing it from the former fungus. The large 

 cells frequently show yeast-like bodies within, hence the characteristic of en- 

 dogenous spore formation. The large round encapsulated cells of C. gilchristi 

 or C. hominis do not show contained spores. The infection frequently becomes 

 generalized. The small bodies, about 3/1, in the Molluscum contagiosum cells 

 are thought by some to be yeasts. They are more probably artefacts. 

 Plimmer's bodies in cancer cells belong in this group. They also are probably 

 other than parasites. 



C. lingua pilose. This is a more or less elongated yeast-like organism and sup- 

 posed to be the cause of black tongue, a benign affection of the lingual papillae. 



GYMNOASCIDAE. Belonging to the family Gymnoascidae we have 

 the genera Trichophyton, Microsporum, Achorion, Endodermophyton 

 and Epidermophyton. 



