What is a solid crystalline substance, C5H13NO2, found in the toadstool (Agaricus muscarius), and in putrid fish. It is a typical ptomaine, and a violent poison called?

muscarin — A solid crystalline substance, C5H13NO2, found in the toadstool (Agaricus muscarius), and in putrid fish. It is a typical ptomaine, and a violent poison. (Webster's 1913.)

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