Large, white, with broad, cream-colored scales on cap, white gills turning gray-green, and a stalk ring. July–September. Cap round, becoming flat; white, with large whitish, pinkish, or cream-colored patches in center; patches breaking into many small scales when cap is open. Gills broad; spacing close; white, becoming gray-green or darker; attachment free. Stalk enlarges toward the base; white, darkens when handled; texture smooth; upper stalk has ring. Partial veil leaves a ring on the stalk resembling a napkin ring. Spore print green. Spores magnified: elliptical, smooth, with small pore at tip.
Lookalikes: Most true Lepiotas have white spore prints. Reddening lepiota (Leucoagaricus americanus) bruises red. Parasol (Macrolepiota procera) has a tall, slender, scaly stalk. Agaricus species have brown spore prints. Thiers amanita (A. thiersii) has a white spore print. Shaggy mane (Coprinus comatus) has a cylindrical cap, turning inky with age, and black spores.