Abstract:Lentinus sapr-caju. and Plewotus ostreatus are widely cultivated commercial edible fungi. In order to distinguish these two species and to clarify their taxonomic position, line-drawings illustrating macro-and microscopic features and morphological descriptions and comparisons are provided in the present paper. It is confirmed that L. sapr-cay should not be placed in Plewotus. The most important distinction between L. sapr-cay. and P. ostreatus, or Lentinus and Plewotus, is the hyphal system forming the basidioma. Lentinus sapr-cay. is dimitic having both generative and skeleto-ligative hyphae (skeletal hyphae, either intercalary or terminal, in some other species of Lentinus) whilst P. ostreatus is monomitic having only generative hyphae (occasionally terminal, tpering skeletal hyphae occur in some other species of Plewotus}. The Chinese scientific names for Lentinus sect.