for the widespread P. semilanceata, but the latter can be distinguished by its larger spores and a conical, papillate cap. Another similar species is Psilocybe silvatica, and a microscope is needed to reliably distinguish between the two species. P. silvatica, found from New York to Michigan and north to Canada, has longer spores. P. pelliculosa has a general resemblance to Hypholoma dispersum, a species found in northern North America and Europe. Habitat and distribution The fruit bodies of P. pelliculosa grow in groups or clusters on moss, forest debris, and humus in coniferous forests. The fungus prefers to fruit in disturbed areas such as trails and abandoned forest roads; it is not commonly found in grasslands. It is known from the Pacific Northwest region of North America where it has been collected in California, Idaho, Oregon, Washington, and it is widely distributed in British Columbia, Canada. It is also found in northern Europe, a single collection from Finland. The fungus often fruits along forest paths and abandoned logging roads where alders and firs are growing. Fruit bodies tend to appear in late summer to early winter after cool, wet weather. Psychoactivity Psilocybe pelliculosa contains the psychoactive compounds psilocybin and baeocystin, and is used as a recreational drug. In terms of psychoactive potency, Stamets considers the species "relatively weak". Psilocybin levels have been reported to range from 1.2 to 1.7 milligrams per gram of dried mushroom, while baeocystin was measured at 0.04%. See also List of Psilocybe species List of Psilocybin mushrooms Psilocybin mushrooms Notes References Cited texts External links Entheogens Fungi described in 1937 Fungi of Europe Fungi of North America Psychoactive fungi pericystis Psychedelic tryptamine carriers Taxa named by Alexander H. Smith