The fatty acid composition of some thermotolerant strains ofDactylaria gallopavaisolated from coal spoil tips has been compared with that of the type strain ofD.gallopava, the original isolation of which was from diseased turkey poults. In addition, the fatty acids of the mesophilic fungiDactylaria ampulliformeandScolecobasidiumspp. were analyzed. The scolecobasidia andD.gallopavahad the same qualitative fatty acid pattern, though quantitatively there were differences, the scolecobasidia having more highly unsaturated lipids thanD.gallopava.D.ampulliformecontained the triply unsaturated γ-linolenic acid and eicosatrienoic acid, and in this respect differed from the scolecobasidia andD.gallopava, which appeared unable to synthesize trienoic acids.