CHAPTER XIII 

 FUNGI RELATED TO THE YEASTS 



IT is deemed advisable to consider, at this time, a few of the fungi 

 belonging to the family Endomyces l or in a doubtful position 

 such as the Monilia and Pseudomonilia; these are set apart from 

 the yeast by the greater complexity of their mycelium but the physio- 

 logical and certain of their morphological characteristics resemble 

 closely the Saccharomycetes from which, at times, they are separated 

 with difficulty. 



ENDOMYCES ALBICANS. Vuillemin 



Syn.: APOROTRICHUM GRUBY OIDIUM ALBICANS. Robin. SYRINGO- 

 SPORA ROKINT. Quinquaud. SACCHAROMYCES ALBICANS. Reess. 



MONILIA ALBICANS. Plilllt. DEMATIUM ALBICANS. Laurent 



This fungus, which causes a sickness known as thrush, has been 

 regarded in turn as an Oidium, a Monilia and a yeast. Since the work 

 of Vuillemin it has been regarded as a member of the genus Endo- 

 myces. In situ and in cultures, Endomyces albicans has somewhat the 

 same characteristics. It possesses a mycelium with cross walls and 

 branches more or less well developed; yeast structures result by bud- 

 ding from the branches. (Fig. 155, 1 and 2.) The mycelium never 

 acquires a marked differentiation and Endomyces albicans, speaking 

 generally, is close to the yeasts. Both structures, yeast-like and myce- 

 lium, are able to change one into the other. The filaments seem able 

 to form the yeast-like bodies and these latter the filaments. Myce- 

 lium formations are more or less well developed, depending on the 

 conditions. In certain cultures the yeast-like structures predominate 



1 The genus Endoiaycw is characterized by a typical branched mycelium 

 with cross walls, forming yeast-like bodies or oidia and chlamydospores, and 

 with ascs containing 4 ascospores. These are formed always at the expense of 

 cells in the mycelium, most often at the end of a branch, exceptionally in some 

 cell in the mycelium. In certain species, the formation of the asc is preceded by a 

 copulation iso- or heterogamic. The genus Endomyces is differentiated from the 

 Saccharomyces by the formation of a typical mycelium and the formation of 

 ascs in mycelial cells and never in the yeast-like structures. However, certain 

 species have (End. javanensis) intermediate characters between the Endomyces 

 and Saccharomycetes which makes it difficult to class them with either one of 

 these two families. 



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