In the fifth issue of this series, 33 species of ectomycorrhiza are described, including representatives of the genera Alpova, Arcangeliella, Boletus, Cortinarius, Descomyces, Lactarius, Russula, Tomentella and Xerocomus, and in addition some unidentified mycorrhiza. For each species a description is given of the morphological and anatomical characters, colour reactions, and chemical properties, as well as extensive discussions and a list of references. The anatomical characters are illustrated in a very elaborate and accurate way with very clear line-drawings. The series is an invaluable tool for all interested in ectomycorrhiza.