introduced the name Gasteromycetes for a class of fungi in his Systema Mycologicum of 1821, although (not using a microscope) he included many species of the Ascomycota (such as truffles) within the class. Fries contrasted the Gasteromycetes with the Hymenomycetes, where spores are produced externally on gills, pores, and other surfaces.

This convenient division continued to be used for the next 150 years or so, although