North American species of Crepidotus, by L.R. Hesler and Alexander H. Smith.

Hesler * Smith

45

25. Crepidotus conchatus sp. nov.
Illustrations: Figs. 74, 75.
Pileus 4-10 mm latus, sessilis, albus, conchatus, villosus velfibrillosus, glabrescens. Lamellae albae deinde pallido-cinnamomeae, latae demum medio-latae, confertae.
Sporae 4.5-5.5 IL, globosae, punctatae. Basidia 20-28 X 5-7!, di- et tetraspora.
Pleurocystidia desunt; cheilocystidia 26-62 X 5-10,t. Cuticula ex hyphis repentibus
composita, plerumque hyphas erectas gerens; pilocystidia cheilocystidiis similia. Fibulatae adsunt. Specimen typicum in Herb. Univ. Mich.; lectum in Bois Blanc Island,
Michigan, July 21, 1961, A. H. Smith 63600.
Pileus 4-10 mm broad, sessile, white, more or less dingy in age, conchate, somewhat villose or fibrillose, glabrescent. Context whitish.
Lamellae white then pale cinnamon, broad or medium broad, close or
moderately close, thin.
Spores 4.5-5.5 It in diameter, globose, punctate. Basidia 20-28 X 5-7
j/, 2-4-spored. Pleurocystidia none; cheilocystidia 26-62 X 5-10 /t, versiform: cylindric, clavate, ventricose, rarely septate. Gill trama subparallel or
slightly interwoven, hyphae 4-10 /u broad. Pileus trama interwoven. Cuticle
of repent hyphae, usually bearing erect hyphae and, at times, pilocystidia
resembling the cheilocystidia. Clamp connections present.
HABIT, HABITAT, AND DISTRIBUTION: On hardwood log, Michigan,JulyAugust.
MATERIAL STUDIED: MICHIGAN: Smith 63600 (type from Bois Blanc
Island,July 21, 1961), 66265.
OBSERVATIONS: This species is distinguished by its white, conchate
pileus, broad gills, and small spores. Its broad gills exclude it from C. applanatus, and its small spores separate it from C. malachius.
26. Crepidotus tahquamenonensis sp. nov.
Illustration: Fig. 76.
Pileus 8-25 mm latus, sessilis, flabelliformis demum reniformis, albus deinde
obscurus, glabrosus. Lamellae latae, confertae, albae deinde sub-brunneae. Sporae 4.5 -5.5 I1, globosae, punctatae. Basidia 16-20 X 6-7 /A, tetraspora. Pleurocystidia desunt;
cheilocystidia 28-42 X 5-13 Iu. Cuticula ex hyphis repentibus composita, hyphas
erectas et pilocystidia gerens. Fibulatae adsunt. Specimen typicum in Herb. Univ.
Mich.; lectum in Tahquamenon Falls State Park, Mich., Aug. 9, 1956, Thiers3907.
Pileus 8-25 mm broad, sessile, flabelliform to reniform, white, becpming dingy in age, glabrous, at times tomentose on the disk or at the base.
Context white; odor and taste mild.
Lamellae broad, close, thin, white becoming brownish.
Spores 4.5-5.5 y in diameter, globose, punctate. Basidia 16-20 X 6 -7 /, 4-spored. Pleurocystidia none; cheilocystidia 28-42 X 5-13 /, clavate
and often capitate or forked, or ventricose. Gill trama subparallel to slightly
interwoven, hyphae 5-8 j broad. Pileus trama interwoven. Cuticle of repent
hyphae, bearing scattered, erect hyphae, at times as cylindric pilocystidia.
Clamp connections present.