Many people are already aware of the psychoactive effects of peyote. There are, however, numerous other cacti that have hallucinogenic properties. Among these are Donana from northern Mexico, San Pedro from the Andes, three related mescaline-bearing species from South America, at least fifteen species used by the Indians of Central America, and at least fifteen species used by the Indians of Central Mexico as peyote substitutes. Botanists and chemists are now studying the constituents of these cacti and are making some remarkable discoveries.
