The North American Species of Crepidotus

104. Crepidotus lanuginosus sp. nov.

Illustration: Fig. 178.

Pileus 10-20 mm latus, primum resupinatus deinde reniformis demum flabelliformis, albidus deinde brunnaceus, longo-fibrillosus vel lanatus, margine incurvatus. Lamellae albae deinde obscuro-fuscae, ochraceae vel obscuro-luteobrunneae, subdistantes vel paene confertae, latae vel medio-latae. Sporae 5.5-7 (8) x 4.5-5.5 µ, ellipsoideae, punctatae. Basidia 24-30 (35) x 6-8 µ, tetraspora. Pleurocystidia desunt; cheilocystidia 27-65 x 3-8 µ, saepe contorta. Cuticula ex hyphis repentibus, brunnaceis, non-incrustatis composita, hyphas erectas, longas, sine colore gerens, 2-3 µ latas. Fibulae adsunt. Specimen typicum in Herb. Univ. Mich.; lectum prope Brundage Mt., Idaho, July 6, 1954, A. H. Smith 44687.

Pileus 10-20 mm broad, resupinate at first, becoming reniform to flabelliform and curving away from the substratum, whitish, becoming brownish as the spores mature, dry, long, fibrillose or woolly, margin incurved, at times fringed.

Lamellae radiating from a lateral point, white, becoming dull tawny to ochraceous or darker yellowish-brown, subdistant or nearly close, broad or medium broad.

Spores 5.5-7 (8) x 4.5-5.5 µ, ellipsoid, slightly inequilateral in profile, minutely punctate, often obscurely so. Basidia 24-30 (35) x 6-8 µ, 4-spored. Pleurocystidia none; cheilocystidia 27-65 x 3-8 µ, cylindric or filamentous, ventricose, often crooked or contorted, at times forked or branched above. Gill trama undulating or regularly parallel to subparallel, hyphae 4-10 µ broad. Pileus trama interwoven. Cuticle of repent, brownish, non-incrusted hyphae, bearing a turf of long, straight, colorless hyphae, 2-3 µ broad. Clamp connections present.

Habit, Habitat, and Distribution: On conifer sticks and limbs, Idaho and California, July.

Material Studied: CALIFORNIA: Cooke 15646, 18448 (MICH); IDAHO: Smith 44687 (type, Brundage Mt., Valley County, July 6, 1954).

Observations: The woolly, fibrillose pileus, with its incurved, often fringed margin are distinctive macroscopic features. The minutely punctate, relatively small spores, together with contorted cheilocystidia, and the brownish hyphae in the cuticular zone, distinguish it.