The North American Species of Crepidotus

82. Crepidotus amarus Murr., Mycologia 35: 430. 1943.

Illustration: Fig. 155.

Pileus 5-8 mm broad, convex, not resupinate at first, reniform or subcircular, uniformly white, unchanging, pulverulent, margin at times slightly striate. Context thin, white; taste very bitter at once.

Lamellae adnexed, broad at the base, distant, inserted, whitish, becoming fulvous, edges beaded, fimbriate. Stipe always present, eccentric, short, slender, curved, white.

Spores 6-8.5 x 5-6 µ, ellipsoid to ovoid, equilateral, wall thick, smooth. Basidia 18-24 x 4-5 µ, 4-spored. Pleurocystidia none; cheilocystidia 33-48 x 3-7 µ, clavate to cylindric, more or less subcapitate, base at times enlarged, often crooked. Gill trama slightly interwoven, hyphae 3-4 u, broad. Pileus trama interwoven. Cuticle of repent hyphae, bearing scattered to numerous (rarely a turf) pileocystidia , 35-55 x 2.5-4 µ, filamentous, often somewhat flexuous, apices at times forked. Clamp connections present.

Habit, Habitat, and Distribution: On dead grape-vine, Florida, June.

Material Studied: Florida: Murrill F 17226, type, from Gainesville, June 28, 1938.

Observations: The presence of a permanent stipe and a very bitter taste should facilitate the recognition of this species.