The North American Species of Crepidotus

11. Crepidotus fraxinicola Murr., North Amer. Flora 10: 150. 1917.

Illustrations: Figs. 45, 46.

Pileus 1-2 cm broad, convex to subexpanded, not at first resupinate, reniform, gelatinous or viscid, dingy-white, or finally pale honey color, shining when dry, at first fibrillose, becoming glabrous, the base strigose-tomentose. Context moderately thin.

Lamellae white to isabelline, rather narrow, close or crowded, lamellulae numerous, edges subentire, whitish, often gelatinous.

Stipe none.

Spores (6) 7-8 (10) x (4) 4.5-5.5 (6) µ, ellipsoid, slightly inequilateral in profile, smooth. Basidia 24-32 x 6-7 µ, 4-spored. Pleurocystidia none; cheilocystidia 30-76 x 3.5-6 µ, slender, clavate-cylindric, to bottle-shaped, clustered; or long (75 µ more or less) when gill-edge is gelatinous and their origin tramal. Gill trama subparallel to slightly interwoven, hyphae 4-6 µ broad. Gill edges often gelatinous. Pileus trama interwoven. Cuticle a gelatinous zone, the zone 100-220 µ thick. The surface of the cuticle bearing hyphae some of which are brownish and not incrusted, at times forming scales; most surface hyphae colorless. Hypodermium distinct. Clamp connections none.

Habit, Habitat, and Distribution: On deciduous wood, Michigan, New York, and Washington, June-August.

Material Studied: MICHIGAN: Smith 66633; NEW YORK: Earle 1507 (NY) the type, on ash, from West Park, July 24, 1903; WASHINGTON (Mt. Rainier National Park): Smith 29301, 30201.

Observations: The description of microscopic characters is based on a study of the type. This species differs from C. mollis chiefly in its lack of incrustations on the brown hyphae of the pileus surface.