Psilocybe merdaria (Fr.) Ricken syn. Stropharia merdaria (Fr.) Quel. (illustrated 40% life size) Cap 2–5cm across, obtusely bell-shaped then flattened convex; ochraceous, more cinnamon when moist; viscid. Stem 50–75×4–6mm; whitish, flushed straw-yellow; dry, base covered in white down. Flesh white, becoming brownish in stem when old; smell none. Gills adnate; pallid then purplish-brown. Spores 10–16×8–9¼, broadly elliptical and often somewhat angular, with germ-pore. Spore print brown-black. Cheilocystidia lageniform, thin-walled, hyaline. Habitat on horse dung; late summer to autumn. Uncommon. Unknown edibility.