The North American Species of Crepidotus

41. Crepidotus angustifolius sp. nov.

Illustrations: Figs. 96, 97.

Pileus 5-10 mm latus, sessilis, flabelliformis demum suborbicularis, pallidocoriaceus, glabrosus. Lamellae angustae, confertae, colore ut flos lactis demum fuscus. Sporae 4.2-5.5 µ, globosae, punctatae. Basidia 22-30 x 5-6 µ, tetraspora. Pleurocystidia 23-38 x 5-8 µ; cheilocystidia 33-56 x 7-12 µ. Cuticula ex hyphis repentibus, pileocystidia adsunt, aut sparsa adsunt, 33-45 x 4-10 µ. Fibulae adsunt. Specimen typicum in Herb. Univ. Mich.; lectum in Tahquamenon Falls State Park, Mich., Aug. 6, 1951, A. H. Smith 37504.

Pileus 5-10 mm broad, sessile, flabelliform or suborbicular, pale buff, glabrous, dry. Context thin.

Lamellae narrow, close, creamy then tawny.

Spores 4.2-5.5 µ, globose, punctate. Basidia 22-30 x 5-6 µ, 4-spored. Pleurocystidia 23-38 x 5-8 µ, clavate, cylindric, or ventricose, at times capitate, scattered, inconspicuous; cheilocystidia 33-56 x 7-12 µ, clavate or ventricose, at times capitate. Gill trama subparallel, of short cells, 5-9 µ broad. Pileus trama radially disposed, appearing as pseudoparenchyma in tangential sections. Cuticle of repent hyphae; pileocystidia none, or present and then scattered, cylindric, clavate, or bottle-shaped, 33-45 x 4-10 µ. Clamp connections present.

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

Material Studied: MICHIGAN: Smith 37504, type, Tahquamenon Falls State Park, Aug. 6, 1951.

Observations: This differs from C. subcuneiformis and subapplanatus in its color and the structure of the pileus trama.