The genus Blastomycoides as a mycological entity

Summary Studies were made on some environmental factors promoting yeast-phase growth ofBlastomycoides in chemically defined media. With inclusion of different tryptophane desaminase inhibitors, pure yeast phase of growth was obtained. The same factors facilitate the development of perfect sexual forms and the observation of the cytological characteristics. Therefore,Blastomycoides, represented byBlastomyces dermatitidis, Bl. brasiliensis, Bl. cerolytica andBl. immitis (formerlyCoccidioides immitis), form a special genus which is very near to the Protomyces and represents a transitory phase between the Endomycetales and the Taphrinales. Although the vegetative mycelium of the Blastomycoides resembles the Aleurismaceae, they cannot be classified as such, especially because they are dimorphic fungi (filamentous-yeast) and their sexual forms are characteristic asci on a very primitive level.Blastomycoides not only represent a group of fungi causing grave visceral mycoses (blastomycoses) but they also are an indiscutable mycological entity, as yet represented in the genusBlastomycoides