Horse Mushroom Agaricus arvensis Schaeff. (illustrated (d) 35% life size) Cap 8–20cm across, ovate at first, expanding convex; creamy white, yellowing slightly with age or on bruising. Stem 80–100×20–30mm, often slightly clavate at the base; concolorous with the cap; tending to become hollow; ring formed of a double membrane, the lower splitting into a star shape around the stem. Flesh white; thick and firm in the cap, pithy in the stem; taste mushroomy, smell of aniseed. Gills free; white at first then flesh-pink, finally chocolate-brown with age. Spores 7–8×4.5–5¼, elliptical. Spore print dark purple-brown. Cheilocystidia 11–26×9–18(21)¼, ovate balloon-shaped, thin-walled. Habitat amongst grass in pasture or thickets, often in rings; autumn. Common. Edible excellent. Note field photograph (d) taken by Geoffrey Kibby.
