Specimens of Radiigera fuscogleba Zeller and Geastrum limbatum Fries were studied both in situ and microscopically during their development and are described in detail. They were found to contain identical cell and tissue types, differing only in the manner of dehiscence of the fruiting body at maturity. The same tissue types were observed in five additional species, four in Geastrum and one in Radiigera. The genus Radiigera is transferred to the Geastraceae. New distributional records for the two species of Radiigera and for Geastrum limbatum are reported for the Pacific Northwest along with photographs and illustrations of the microscopic features of both taxa.