The group may be divided into two main divisions, Hymenomycetes and Gasteromycetes.

I. of this work contains descriptions and valuable original comments of all the Hymenomycetes, Gasteromycetes, and Hypodermei met with in Holland.

This important discovery led to the correlating of the Gasteromycetes with the Hymenomycetes under the common title Basidiomycetes, both having the spores borne upon basidia.