The North American Species of Crepidotus

40. Crepidotus malachius var. phragmocystidiosus var. nov.

Illustration: Fig. 95.

Pileus 3-7 cm latus, sessilis,flabelliformis demum semiorbicularis, albus, glabrosus vel villosus, striatus. Lamellae confertae, latae, brunneae. Sporae 5-7.5 µ, globosae, punctatae. Basidia 30-37 x 6-7 µ, di- et tetraspora. Pleurocystidia desunt; cheilocystidia 37-62 x 6-12 µ, interdum septata. Cuticula ex hyphis repentibus perraro erectis composita. Fibulae adsunt. Specimen typicum in Herb. Univ. Mich.; lectum prope Emerson, Mich., Aug. 18, 1959, A. H. Smith 61452.

Pileus 3-7 cm broad, sessile, flabelliform to semiorbicular, white, glabrous, or at times somewhat villose, margin striate.

Lamellae close, broad, finally wood brown.

Spores 5-7.5 µ, globose, punctate, earth brown. Basidia 30-37 x 6-7 µ, 2-4-spored. Pleurocystidia none; cheilocystidia abundant, 37-62 x 6-12 µ clavate, more or less cylindric and often slightly capitate, at times ventricose, occasionally septate. Gill trama subparallel, hyphae (3) 7-17 µ broad. Pileus trama interwoven. Cuticle of repent hyphae, only rarely with more or less erect hyphae. Clamp connections present.

Habit, Habitat, and Distribution: On hardwood, Michigan, July–August.

Material Studied: MICHIGAN: Smith 61105, 61452 (type, from Emerson, Aug. 18, 1959), 61474.

Observations: Some of the cheilocystidia are septate—a character which distinguishes this variety. In Smith's No. 61105 the pilei are much smaller than is typical for this variety, but it is included here because of its microscopic structure.