The North American Species of Crepidotus

107. Crepidotus vulgaris sp. nov.

Illustrations: Figs. 25, 181.

Pileus 6-20 (40) mm latus, sessilis, conchatus deinde dimidiatus, albus deinde albidus vel brunnaceus, pubescens. Lamellae albae deinde brunnaceae, latae vel mediolatae, confertae vel paene subdistantes. Sporae (5) 6-8 x 4-5.5 µ, ellipsoideae, punctatae. Basidia 22-33 x 6-7 µ di- et tetraspora. Pleurocystidia desunt; cheilocystidia 28-50 x 5-9 (16) µ. Cuticula ex hyphis repentibus composita, hyphas erectas sine colore gerens, 2.5-4 µ latas. Fibulae adsunt. Specimen typicum in Herb. Univ. Mich.; lectum prope Pellston Hills, Mich., July 21, 1961, A. H. Smith 63570b.

Pileus 6-20 (40) mm broad, sessile, or with a pseudostipe, conchate then dimidiate, white, at times remaining so when dried, or becoming brownish, villose or pubescent, base often strigose. Context thin, soft, white; odor and taste mild.

Lamellae radiating from a lateral point, white then brownish, broad or medium broad, close or nearly subdistant.

Spores (5) 6-8 x 4-5.5 µ, ellipsoid, inequilateral in profile, punctate. Basidia 22-33 x 6-7 µ, 2-4-spored. Pleurocystidia none; cheilocystidia 28-50 x 5-9 (16) µ, clavate, ventricose, at times constricted, or flask-shaped. Gill trama subparallel or slightly interwoven, hyphae (3) 5-10 µ broad. Pileus trama interwoven. Cuticle of repent hyphae, bearing a turf of colorless hyphae, 2.5-4 µ broad. Clamp connections present.

Habit, Habitat, and Distribution: On hardwood and conifer wood, Massachusetts, New Hampshire, North Carolina, Tennessee, Michigan, and Washington, June-September.

Material Studied: MASSACHUSETTS: Bigelow 8576 (MASS); Smith 67284; MICHIGAN: Thiers 2881, 3350 (MICH); Smith 49768, 63531, 63557, 63570b (type, from Pellston Hills, July 21, 1961), 66951, 67054; NEW HAMPSHIRE: Bigelow 11778; NORTH CAROLINA: Hesler 14198, 17638; TENNESSEE: Hesler 14173; WASHINGTON: Smith 39873.

Observations: The distinguishing characteristics of C. vulgaris are its punctate spores, white then brown gills, regular cheilocystidia, and straight hyphae on the pileus. In C. subsphaerosporus the spores are punctate-echinulate, more broadly ellipsoid, and the lamellae are white then pinkish.