A grant from the Ohio Biological Survey awarded to Harold W. Keller in 1974 supported field research on "The Corticolous Myxomycetes of Ohio" that emphasized the myxomycetes that grow and fruit on the bark surface of living trees and vines. Keller and his associates made over 600 myxomycete collections. These collections added 58 new records for Ohio, bringing the total number of Ohio myxomycetes to 215. This number represents about 61 percent of the 350 species known from North America, and about 36 percent of the 600 species known world wide. At least 64 of the 88 counties in Ohio are represented by 215 different taxa.
Species new to science and Ohio described by Keller in previous publications are: Arcyria pausiaca, Badhamia rugulosa, Didymium orthonemata, D. synsporon, Echinostelium coelocephalum, Licea inconspicua, L. scyphoides, Macbrideola declinata, and Trabrooksia applanata. Corticolous species seldom collected that are new records for Ohio are: Arcyria brunnea, Badhamiopsis ainoae, Clastoderma debaryanum var. imperatorium, C. pachypus, Comatricha ellae, C. fimbriata, Stemonitis curiosa, Cribraria confusa, C. minutissima, Diderma chondrioderma, Didymium sturgisii, D. verrucosporum, Echinostelium brooksii, E. fragile, Licea marginata, L. operculata, Macbrideola cornea, M. scintillans, Minakatella longifila, Physarum aeneum, P. crateriforme, P. javanicum, and P. synsporum. The systematic treatment for each species includes sections on updated synonymy, illustrations, collections examined, and discussion.
Special sections on geographic distribution, habitats, collection and care of specimens, the moist chamber technique, ecology, life cycle, microscopic study of specimens, and keys to the orders, families and genera are provided. The importance of Myxomycetes in several areas of research is discussed, such as: outer space (microgravity environment), food production, medicine, and cell biology. The authors have provided laboratory exercises using Myxomycetes in classroom teaching at the high school (Braun) and university (Keller) level. There is a glossary of morphological tenns and a bibliography where more than 150 references are cited. Also provided are water colour illustrations prepared by Ka Botzis and habit colour photographs that will enable students to picture key some of the more common species.