In the following account twenty-eight heretofore undescribed species of Galerina are treated. These were collected in the Great Lakes region and along the Pacific Coast during the period from 1935 to 1952. As a rule, species of Galerina are not a conspicuous element in our agaric flora, but during the warm dry season of 1952 they were found in abundance in Mount Rainier National Park. During the fall of 1952 no appreciable amount of rain fell in the Park from around the tenth of September until the end of October, and the forest floor, ordinarily covered during this period with fruiting bodies of many species in various genera of the fleshy fungi, was barren. Fungi were found only at high elevations and in local pockets where there was moisture and protection from the sun. One notable area of this sort was at Green Lake in the Carbon River district of the Park. The north-facing slopes of the Tatoosh Range furnished many favorable spots, such as that around Snow Lake. Collecting was carried on in these areas as well as at higher elevations until long after the usual time for the fall snows and the advent of winter. Thus the 1952 season in the Park was truly unusual, and served well to illustrate the need for collecting in an area under all types of weather conditions before drawing many conclusions about either the diversity of a fungous flora or the fruiting pattern of the species comprising it. During the season of 1948, one of the wettest years in the history of the Park, the same areas produced practically nothing in the way of fungi during the summer and were covered by snow early in September. Kuhner (1) monographed Galerina for France as part of a treatment of the Friesian genus Galera. In this work he emphasized spore structure as one of the important diagnostic characters. As he defined the genus, the smooth suprahilar depression or "plage" of the spore was the central character, and this has been followed by Singer (3). . It is also followed in the present paper. Both earlier authors included entirely smooth-spored species in the genus, as I have done here, and a few in which the suprahilar area as well as the rest of the spore surface is roughened. However, the latter species are regarded as peripheral. Assignment to Galerina, in such instances, is of course made on the aggregate of all the other characters. In his work Kuhner treated eighteen species. I have accounted for practically all of these in North America; the twentyeight additional species treated in this paper are only the more outstanding discoveries that we have made. In fact, when the study is complete, I predict that there will be around sixty species from North America. Thus Galerina is not a small genus, as some have thought. Smith and Singer are at present engaged in a monographic study of the genus, and for this reason illustrations of carpophores, drawings of microscopic characters, and discussions of relationships and speciation are not presented here. These can all be treated more effectively in a work dealing with all known species. The type collections are deposited in the University of Michigan Herbarium. In regard to species collected in our national parks, if the collections were large enough to be divided, a part has been deposited in the Mount Rainier National Park Herbarium. The color terms in quotation marks are taken from Ridgway. The observations on the spores were made from dried specimens revived in 2.5 percent KOH, and viewed with a 1.3 NA oil-immersion objective and a 15 X eyepiece. This is important to anyone seeking to compare spores with the descriptions published here because the spore markings are exceedingly minute in some species. The collecting expeditions on which these fungi were obtained were made possible largely by grants from the Faculty Research Fund of the University of Michigan during the years from 1935 to 1952, and in part by the generosity of Mr. Wm. B. Gruber of Portland, Oregon. The University of Michigan Herbarium also financed some of the field work during this period, and facilities for the collec ing in northern Michigan were furnished by the University of Michigan Biological Station located on Douglas Lake. I am particularly indebted to the National Park Service for its cooperation in furnishing facilities, equipment, and other aids upon a number of occasions. I wish, again, to express my personal appreciation to Superintendent Preston P. Macy and his staff for courtesies extended to me on my visits to the Olympic National Park in 1939 and 1941; to Mr. John C. Preston, then superintendent of Mount Rainier National Park, for courtesies extended to my party at Mount Rainier during the season of 1948. Superintendent Preston P. Macy, now of Mount Rainier National Park, and his staff were of great assistance during the dry season of 1952. It was through the guidance of members of the naturalist staff that the best localities were found and visited during 1952.