The North American Species of Crepidotus

120. Crepidotus ramosus sp. nov.

Illustration: Fig. 196.

Pileus 8-15 mm latus, sessilis, glabrosus vel subglabrosus, disco coriaceus, margine albus. Lamellae luteo-brunneae, confertae, latae, marginibus pallidae, denticulatae. Sporae 6.5-8 x 5.5-6 µ ellipsoideae vel subovoideae, punctatae, echinulatae. Basidia 26-32 x 6-8 µ, tetraspora. Pleurocystidia desunt; cheilocystidia 34-58 x 4-11 µ, contorta. Cuticula ex hyphis repentibus composita, hyphas erectas sine colore gerens, 20-50 x 2-3 µ. Fibulae adsunt. Specimen typicum in Herb. Univ. Mich.; lectum prope Trout Lake, Colo., Aug. 17, 1956, A. H. Smith 52374.

Pileus 8-15 mm broad, sessile, disc buff, margin white, glabrous or nearly so.

Lamellae clay brown, close, broad, edges paler, denticulate.

Spores 6.5-8 x 5.5-6 µ, ellipsoid, at times subovoid, inequilateral in profile, punctate-echinulate. Basidia 26-32 x 6-8 µ, 4-spored. Pleurocystidia none; cheilocystidia 34-58 x 4-11 µ (below apex), clavate, subcylindric, ventricose, irregularly branched, forked, knobbed, contorted. Gill trama interwoven, hyphae 5-10 µ broad. Pileus trama interwoven. Cuticle of repent hyphae, bearing scattered, more or less erect, colorless hyphae, 20-50 x 2-3 µ. Clamp connections present.

Habit, Habitat, and Distribution: On spruce, Colorado, August.

Material Studied: COLORADO: Smith 52374, type, from Trout Lake, San Juan Mts., Aug. 17, 1956.

Observations: The conspicuous, contorted branching of the cheilocystidia is a distinctive character of this species.