This work is the result of innumerable excursions, made over fifteen years, dedicated to finding the species belonging to genus Inocybe. In this work of 460 pages there are approximately 150 species described by the author with 256 colour photocolors and 144 micrographies. This is the only book with colour photocolours of genus Inocybe in the world of mycological literature. The systematic order and the taxonomic-nomenclature statement used are that proposed by M.BON. The taxa are:
Inocybe tigrina f. mesophaea Bon & E. Ferrari f. nov.
Inocybe subbrunnea var. flavidifolia E. Ferrari var. nov.
Inocybe pseudoasterospora var. mycenoides Bon & E. Ferrari var. nov.
Inocybe viscosissima var. bulbosovelata Bon & E. Ferrari var. nov.