ergot /ur″gət/ [L, ergota, a grain fungus] , a fungus structure that replaces the seed of rye and other cereal grasses infested with the parasitic fungus Claviceps purpurea. Ergot contains ergot alkaloids, the agents responsible for what was known as St. Anthony’s fire in people who consumed the contaminated grain in the Middle Ages. Effects included hallucinations and such intense vasoconstriction in the extremities that portions of the limbs often developed gangrene and fell off before the person died.
