Section Celluloderma of the genus Pluteus is subdivided into two subsections, Mixtini and Celluloderma. In the following account, four species are discussed for subsection Mixtini. Pluteus eugraptus is reported new for North America. Subsection Celluloderma for North America contains twenty species and varieties. One species, Pluteus pallidus is described as new. Another species and one variety are provisionally described as new. Keys to subsections Mixtini and Celluloderma are provided along with illustrations of important structures, photos of a number of species, and descriptions of the well-known species.