Describes the botany, history, distribution, cultivation, preparation, and dosage of more than 400 psychoactive plants and fungi. The encyclopedia also offers information on ritual and medicinal use. Also includes 168 detailed monographs on the major psychoactive plants (e.g., Cannabis, Datura, and Papaver) as well as 20 full monographs on psychoactive fungi (e.g., Psilocybe and Amanita).