The North American Species of Crepidotus

2. Crepidotus pubescens Bres., sensu Kühner & Romagnesi Icon. Myc. t. 790/2. 1930.

Illustration: Fig. 35.

Pileus 3-12 mm broad, conchate, dimidiate, to orbicular, the margin at times pleated or wavy, surface dry, pure white, white-felted base with a slight pubescence, extreme margin faintly pubescent-fimbriate. Context thin soft and white, without odor or taste.

Lamellae close, 2-3 tiers of lamellulae, narrow, white but soon "pinkish buff" or bright cinnamon buff to orange-buff, edges even or minutely fimbriate under a lens, attached at base of pileus or to a slight pseudostipe.

Spore deposit "pinkish buff" or "orange-buff." Spores (6) 7-9 x 2.5 -3 (3.3) µ, often clinging in two's, three's, or four's, subfusoid or pip-shaped in front view, slightly allantoid in profile, smooth, thin-walled, pale to nearly colorless in 2% KOH. Basidia 17-27 x 4-6 µ, 4-spored. Gill trama interwoven. Pleurocystidia none; cheilocystidia 35-75 x 3-10 µ, filamentous, usually crooked, at times branched, the basal portion sometimes clavate-enlarged and the apex surmounted by a long, crooked (more rarely coiled) neck. Pileus trama interwoven. Cuticle repent, with a broad (250-400 µ), colorless zone of loosely interwoven, more or less crooked hyphae forming a turf-the hyphae at first appearing gelatinous but there is no swelling in 2% KOH. Clamp connections none on the hyphae of the carpophore (found only on the hyphae of the pubescence at the point of attachment).

Habit, Habitat, and Distribution: On fallen twigs and leaves of deciduous and coniferous trees, Idaho, Oregon, and Michigan, October–November; also Europe.

Material Studied: IDAHO: Smith 54060; MICHIGAN: Smith 66272; OREGON: Smith 55365, 55561; NETHERLANDS: Bas 983.

Observations: The fusoid spores and the shape of the cheilocystidia distinguish this from C. herbarum. Pilát (1948) proposes for it a new name, C. bresadolae, for the reason that the name Agaricus pubescens was used for a different species in Flora Danica in 1792. Pilát (1948) and Lange (1939) list Britzelmayer's terricola as a synonym.