The peyote cactus, or Lophophora williamsii, is unassuming at first glance. It’s small and spineless, unlike other cacti. But inside the small buttons that grow from the plant lies a hallucinogenic ...

Peyote is a small, button shaped cactus native to Mexico and southern parts of the United States. Potent compounds in peyote, such as mescaline, cause it to have a hallucinogenic effect in humans.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American In 2002, on assignment for Discover Magazine, ...