Liberty Cap Mushrooms

Psilocybe semilanceata, commonly known as the liberty cap, is a species of fungus that produces the psychoactive compounds psilocybin and biocytin. It is both one of the most widely distributed psilocybin liberty cap mushrooms in nature, and one of the most potent.

The cap of P. semilanceata is 5–25 mm (0.2–1.0 in) in diameter and 6–22 mm (0.24–0.87 in) tall. Liberty Cap varies in shape from sharply conical to bell-shaped, often with a prominent papilla (a nipple-shaped structure), and does not change shape considerably as it ages.

The Liberty cap mushrooms margin is initially rolled inward but unrolls to become straight or even curled upwards in maturity. The cap is hygrophanous, meaning it assumes different colors depending on its state of hydration. When it is moist, the cap is ochraceous to pale brown to dark chestnut brown, but darker in the center, often with a greenish-blue tinge.

Psilocybe caerulipes

When moist, radial grooves (striations) can be seen on the cap that corresponds to the positions of the gills underneath. When the cap is dry, it becomes much paler, a light yellow-brown color. Moist liberty cap mushrooms have sticky surfaces that result from a thin gelatinous film called a pellicle. This film becomes apparent if a piece of the cap is broken by bending it back and peeling away the piece. When the cap dries from exposure to the sun, the film turns whitish and is no longer peelable.