SUMMARYThe essential oil ofCeratocystis virescenswas analyzed by means of gas and thin-layer chromatography, infrared spectrometry, mass spectrometry and chemical means. The oil fromC. virescenswas compared for chemotaxonomic purposes with that ofC. variospora.The major constituents in the oil ofC. virescenswere: 6-methyl-5-hepten-2-ol acetate, linalool and geranyl acetate. One cyclic terpene, a-terpineol, was isolated.