Certain fermentative characteristics of the ringworm fungi seem to differentiate them from other organisms of similar morphology. The term "ringworm fungi" is a convenient one for the group which comprises the allied genera Achorion, Microsporon, Trichophyton and Epidermophyton, the members of which are the infective agents in favus and the various types of ringworm.
The identification of these organisms by methods in vogue is not easy. For example, it seems impossible to define the genus Trichophyton by known morphologic and cultural characteristics so as to include all members of that genus and exclude all other fungi. It was for this reason that we have attempted to determine whether fermentation reactions which have found such a wide use in bacteriology and have been successfully applied by Castellani1 to the moniliae might not also be helpful in the study of the dermatophytes.
Very little previous work has been reported in this