Peyotl and mescaline.

Although only more recently studied than the well known mescaline-containing peyote cactus (Lophophora williamsii) of North America, the use of mescalinecontaining Cactaccae in South America now appears to be far older archeologically. Four Andean Trichocereus species contain the hallucinogenic drug mescaline: 7'. macrogonus; T. terscbeckii; T. werdermannianus; and T. pachanoi. Of these, the last is the most important ethnographically. Trichocereus pachanoi is a smooth, ribbed, comparatively slender, night-blooming, columnar species of cactus which was located in Andean Ecuador by Britton and Rose in 1920; in 1959 the German botanist Curt Backeberg extended this area to include northern Peru and Bolivia. In Peru this Trichocereus is known in folk medicine as "San Pedro" and in Ecuador as aguacolla. San Pedro als forms a part of the hallucinogenic drink cimora, which also includes other Cactaceae and a datura. The mescaline content of San Pedro is about 0.12 percent of the green plant and two percent when dried. In 1939 the Swedish pharmacologist Stig Agurell discovered seven other alkaloids in the plant but these occur in insignificant quantities. Peruvian medicine men most commonly use a sevenribbed San Pedro cactus in their shamanistic cures. But the rarer four-ribbed specimens, like a four-leaved clover, are regarded as especially lucky and powerful, because these symbolize the "four winds" and "four