346 



PATHOGENIC YEASTS 



and a thick membrane. (Fig. 147.) In cultures, it has cells without 

 capsules, elongated and mixed with mycelial filaments. 

 No alcoholic fermentation is brought about nor scum 

 formed on carbohydrate media. It does not liquefy 

 gelatin. It is hardly pathogenic for animals. 



Echon-Echeug have recently found a yeast in the 

 serous secretion from a lesion in the cervical region, 

 simulating cutaneous tuberculosis. The cells are 



Fig. 147. Crypto- spherical (7-16 /A), united two by two. The cultures 



(after Gilchrist). on Sabourand's agar has yielded white colonies which 



be'come brownish, made up of a mycelium producing 



cells like those found in the lesions. 



CRYPTOCOCCUS TOKISHIGEI (Tokishige). Vuillemin 



Syn.: CRYPTOCOCCUS FARCIMINOSUS, Rivolta and Micellone. SACCHA- 

 ROMYCES EQUI, Marcone. CRYPTOCOCCUS RIVOLTAE, Fermi and 



Aruch. PARENDOMYCES OF RIVOLTA AND MICELLONE. BeUT- 



mann and Gougerot 



This yeast was discovered by Rivolta and was considered by this 

 author as the parasite of epizootic lymphangitis or African glanders, 

 a communicable infection of horses and mules. Numerous authors 

 have thought that they cultivated 

 this organism. Fermi and Aruch 

 thought that they obtained it on 

 potato and San Felice said that he 

 reproduced the disease by cultures. 



Marcone and Tokishige were the 

 first to obtain the development of 

 the fungus but they were unable to 

 cultivate it in series. Tokishige in 

 Japan has been able to obtain 

 colonies on quite diverse media, but 

 could not produce the disease when 

 inoculating a horse with the colonies. 

 More recent studies by Negre and 

 Bride and Negre and Boquet have 

 demonstrated that the parasite of this 

 disease is indeed a yeast. In a few animals, the organism possessed 

 the shape of a yeast. They secured best growth of the Cryptococcus 

 by sowing a drop of pus on horse dung agar and covering it with 

 the deposit of a maceration of lymphatic ganglions. The colonies are 



Fig. 148. Cryptococcus Tokishigei. 



1 , Cryptotoccus in a leucocyte. R, Round Form 

 of the Cryptococcus. T, Myeelial tube form- 

 ing a bud. The bud is still within the Leuco- 

 cyte. 2, Mycelial Tubes Formed by the 

 Budding of an External Spore S. T, Mycelial 

 Tube. 3, External Spore. 4, Its Bud. 5, 

 Chlamydospore in a Mycelial Tube. 6, Free 

 Chlamydospore. 7-9, Free units of an old 

 culture. 



