Pleurotus lignatilis (Pers. ex Fr.) Kummer Mehlweisser Seitling. Cap 1.5–5cm across, slightly depressed, creamy white. Stem 5–20 x 4–8mm, central or slightly excentric, whitish discolouring ochraceous. Flesh white. Gills crowded, white then ochraceous-cream. Spore print white. Spores oval, 4.5 x 2.5um. Habitat on dead deciduous wood, especially inside the hollow trunks of beech and elm. Season autumn. Uncommon. Edibility unknown -avoid. Distribution, America and Europe.