Together, Wasson and botanist Roger Heim collected and identified various species of family "Strophariaceae" and genus "Psilocybe", while Albert Hofmann, using material grown by Heim from specimens collected by the Wassons, identified the chemical structure of the active compounds, psilocybin and psilocin. Hofmann and Wasson were also among the first Westerners to collect specimens of the Mazatec hallucinogen "Salvia divinorum", though these specimens were later deemed not suitable for rigorous scientific study or taxonomic classification. Two species of mushroom, "Psilocybe wassonii" R.Heim and "Psilocybe wassoniorum" Guzman & S.H.Pollock, were named in honor of Wasson by Heim and Gastón Guzmán, the latter of whom Wasson met during an expedition to Huautla de Jiménez in 1957.