A comparison of basidial structures in the two species of Filobasidiella by scanning electron microscopy showed similar morphology for the basidia. Globose swellings developed into oval to clavate mature basidia which produced chains of basidiospores by budding at four points on the apical surface, with sterigmata lacking. F. bacillispora sometimes developed a typical basal swelling during enlargement of the clavate basidium. The basidiospores of F. neoformans were larger, with irregularly roughened walls and lemon-shaped to oval in contrast to the smooth, rod-shaped basidiospores of F. bacillispora.