Thirteen new species and a new variety of Psathyrella are described: P. badia, P. bernhardii, P. borgensis, P. capitatocystis, P. dennyensis, P. minutissima, P. mookensis, P. multicystidiata, P. perpusilla, P. ploddensis, P. romseyensis, P. twickelensis, P. vyrnwyensis, and P. obtusata var. aberrans. Some rectifications in the keys published in our monograph (Kits van Waveren, 1985) and some reconstructed keys necessitated by the insertion of new species are given. Recently described new species from outside the area covered by our monograph are briefly described and discussed. Corrections in and supplementary information to some of our descriptions in the monograph and a redescription of P. obtusata are presented.