The North American Species of Crepidotus

16. Crepidotus versutus (Pk.) Sacc., Syll. Fung. 5: 888. 1887.

Agaricus versutus Pk., N.Y. State Mus. Ann. Rept. 30: 70. 1878.

Illustrations: Figs. 56, 57.

Pileus 5-14 mm broad, at first resupinate, then reflexed, attached dorsally or laterally, flabelliform or dimidiate, dry, white, villose to tomentose, margin even, incurved. Context thin, soft, white; odor and taste mild.

Lamellae radiating from an eccentric or lateral point, medium broad, ventricose, sub-distant, white at first, finally tinged rusty or "sayal brown," many short, edges fimbriate.

Stipe none, at times a short tubercle.

Spores 7-11 x 4.5-6 µ ellipsoid, very minutely punctate, yellowish to yellowish-brown (under microscope). Basidia 27-32 x 6-7 µ, 4-spored. Pleurocystidia none; cheilocystidia 22-63 x 3-12 µ, cylindric, subventricose, or bottle-shaped. Gill trama interwoven or at times subparallel, hyphae (2) 4-7 µ broad. Subhymenium parallel. Cuticle of interwoven hyphae, bearing a tuft of colorless, long, slender (2.5-5 µ broad) hyphae. Clamp connections none on the epicuticular hyphae, but found on the hyphae of the tomentum at the base of the pileus.

Habit, Habitat, and Distribution: On bark of deciduous wood, New Hampshire, New York, Michigan, and Tennessee, August-October.

Material Studied: MICHIGAN: Bailey 89 (MICH); NEW HAMPSHIRE: Bigelow 12333 (MASS); NEW YORK: Peck, type (NYS), from Forestburgh, September; TENNESSEE: Hesler 21030.

Observations: The rather large, punctate, ellipsoid spores, and the white, tomentose to villose pileus, are important characters of this species. It seems to have been collected rather infrequently in North America. The following notes are drawn from a study of the type: "Spores 7.5 -10(11) x 4.5-5.5 µ, ellipsoid, faintly punctate (seen best in Melzer's; easily overlooked in water or 2% KOH mounts), yellowish-brown under microscope. Basidia 27-32 x 6-7 µ, 4-spored. Pleurocystidia none; cheilocystidia 34-54 x 4-7 µ, hyphoid, cylindric, subventricose, or bottle-shaped, numerous when found (absent in some sections). Gill trama of undulating-subparallel, narrow (2-5 µ) hyphae. Pileus trama of interwoven hyphae. Cuticle of interwoven hyphae bearing a turf of long, colorless, slender hyphae 2.5-5 µ broad. Clamp connections present on the hyphae forming the tomentum at the point of attachment, but none on the epicuticular hyphae."