Abstract
Summary: Certain taxonomic problems of long standing within the heterobasidiomycete complex are reviewed and recommendations for a rearrangement in the classification of tremellaceous fungi (sensu lato) are suggested whereby the subclass Heterobasidiomycetidae is modified to exclude the Dacrymycetaceae. A new subclass, Metabasidiomycetidae, is erected and includes the holobasidiaceous Dacrymycetaceae and Ceratobasidiaceae as well as the Tulasnellaceae, the latter embracing such genera asMetabourdotiaandPseudotulasnella, which have incompletely divided basidia. The Ceratobasidiaceae as newly constituted, includes besidesCeratobasidiumthe generaOliveonia, Thanatephorus, andUthatobasidium.