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ACHORION SCHONLEINII. Schonlein (1839). 



THE FUNGUS OP FAVUS. 



Origin. Found in the scaly accumulations on the 

 skin of persons afflicted with favus. 



Form. Apparently belongs to the moulds. It shows 

 on microscopical examination peculiarly twisted threads, 

 which show divisions and give off branches at right angles. 



Fruit-organs. No true fruit organs observed, but 

 on special media as on blood-serum at 30 0. conidia or 

 spores form. 



Anilin Dyes. Stains well, also by Gram's method. 



Growth. Is rather slow. 



Plates. On gelatin plates, the colonies grow slowly and form whitish, 

 stellate masses, which rapidly liquefy the gelatin. No conidia present. 



Slich Cultures. Growth is very poor in the lower part of the gelatin 

 tube. On the surface it forms a white covering, the lower side of which is 

 light yellow. Liquefies. 



Streak Cultures. On agar it forms a closely adherent, whitish, dry mass. 



Temperature. Dies out at the ordinary tempera- 

 ture. The optimum is about 30 C. 



Behavior to Gelatin. Liquefies. 



Pathogenesis. Inoculation with pure culture pro- 

 duces typical favus in man. 



The favus fungus is closely related to that of Herpes 

 tonsurans the Tricophyton tonsurans (1845); to that of 

 Pityriasis versicolor the Microsporon furfur (1846); and 

 also to the Oidium lactis. 



