Pleurotus ostreatus (Jacq. ex Fr.) Kummer Austernseitling, Austernpilz Pleurote en forme d'huître Oyster Mushroom. Cap 6–14cm across, shell-shaped, convex at first then flattening or slightly depressed and often wavy and lobed at the margin or splitting, variable in colour; flesh-brown or deep blue-grey later more grey-brown. Stem 20–30´10–20cm, excentric to lateral, or absent, white with a woolly base. Flesh white. Taste and smell pleasant. Gills decurrent, white at first then with a yellowish tinge. Spore print lilac. Spores subcylindric, 7.5–11 x 3–4um. Habitat often in large clusters on stumps and fallen or standing trunks, usually of deciduous trees, especially beech. Season all year. Common. Edible and good. Distribution, America and Europe.