356 PATHOGENIC YEASTS 



exists as solitary cells or grouped in two; they are round or oval with 

 a thick membrane without a capsule (3-5 fJL X 2.8-4.3 ju). 



In old cultures, the cells often present abnormal forms, either 

 sausage shaped or in chains, the cells of which are capable of branching 

 into a rudimentary mycelium; there are also a number of giant cells 

 present. The yeast develops easily and abundantly in most nutritive 

 media. On carrot, small, round colonies are produced which become 

 confluent but irregular and viscous. On potato, the growth is feeble 

 with very small, white, dry colonies. 



On agar plates, vegetation is abundant as a viscous layer with 

 irregular edges becoming yellow. There is no liquefaction. 



On fruit juices, glucose or saccharose solutions, there is feeble 

 development as sediment. No scum is formed. On Raulin's fluid, 

 there is scant development as a deposit with spherical cells (3.5 x 6.4 jut). 



CRYPTOCOCCUS LESIEURI. Beauverie and Lesieur 



This yeast was isolated from an ulcer of the stomach during a 

 complication with typhoid fever. On beer wort, it has very small 

 rounded or oval cells (2-3 /*). These may elongate and become 

 curled. The elongated cells are also found united in filaments. 

 On beer wort agar, the yeast shows a white creamy colony with the 

 surface finely folded. It develops at 27-37 C. On beer wort after 9 

 hours there is a delicate ring with floating islands of scum. Only 

 dextrose is fermented. Animal inoculation has not yielded positive 

 results. 



CRYPTOCOCCUS SULFUREUS. Beauverie and Lesieur 



This yeast was isolated from a pharyngeal exudate during an at- 

 tack of typhoid fever. On carrot, the cells are elongated, sometimes 

 round (2-8 M in diameter). This yeast develops well at 25 C.-37 C. 

 There is a ring formed on beer wort after 23 hours. Dextrose, lactose 

 and saccharose are fermented slightly. On wort agar, the colonies are 

 white with a shiny surface and rounded edge. 



CRYPTOCOCCUS ROGERL Sartory and Demanche 



This yeast was isolated from a peritonitis caused by a perforation 

 of the stomach. The cells are long (3-10 X 2-3 M). 



This yeast is pathogenic for the rabbit and guinea pig. It vege- 

 tates on most of the culture media. It was also found by Beauverie 

 and Lesieur in the pharyngeal exudate of typhoid fever. 



