Amanita polypyramis

Amanita polypyramis is a species of Amanita found in the Eastern United States. It is a large, bone white mushroom with a chlorine-like odor. Its species name, polypyramis, refers to the pyramid-like warts on the surface of the pileus (cap).

Though listed in some sources as ranging from New Jersey, to Costa Rica in Central America, the species has been found as far north as New England, concentrated largely in Cape Cod.