The veiled species of Hebeloma in the western United States / Alexander H. Smith, Vera Stucky Evenson, and Duane H. Mitchel.

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The Veiled Species of Hebeloma

Hymenium.-Basidia 4-spored, 9-11 [lm broad near apex. Pleurocystidia none. Cheilocystidia abundant, when young many fusoidventricose and 37-52 x 7-11 [lm, in age mostly filamentous and 4-6
Jim wide (or retaining a ventricose portion below), walls slightly refractive, apex subcapitate in many.
Lamellar and pilear tissues.-Lamellar trama typical of the genus.
Cuticle of pileus a thin ixocutis, hyphae 3-4.5 Jim diam and the walls
of some with incrustations, gelatinization very slight. Hypodermium
cellular, with copious pigment deposits on the walls. Tramal hyphae
typical of the genus. Clamps present.
Habit, habitat, and distribution.-Gregarious on swampy soil
under spruce, Savage Lakes area, Pitkin County, Colorado, August
23, 1978 (type, MICH).
Observations.-This species is distinguished by the pale gray veil,
the decidedly ventricose + distant gills which are avellaneous at first,
the nondextrinoid spores, and lack of a distinctive odor and/or taste.
The problem with the cheilocystidia is whether or not the ventricose
cells actually become filamentous or whether as maturity is reached the
cells formed later are mostly filamentous. This accounts for changing
ratios of the two types from young to old specimens.
92. Hebeloma cinereostipes sp. nov.
Pileus 2-3.5 cm latus, demum late convexus vel planus, subviscidus, ad marginem tenuiter fibrillosus, demum glaber, sordide vinaceobrunneus ("Warm Sepia") vel obscure vinaceobrunneus; odor et gustus
mitis. Lamellae latae, confertae, obscure cinnamomeae. Stipes 2-4 cm
longus, 3-6 mm crassus, griseofibrillosus, sursum sericeus, deorsum
brunnescens. Sporae 11-14 x 5.5-7 pJm, tarde subdextrinoideae, subfusiformes. Cheilocystidia 34-65 x 7-12 x 4-6 iLm, fusoid-ventricosa.
Specimen typicum in Herb. Univ. Mich. conservatum est, Smith
88733; legit prope Elk Wallow, Fryingpan River, Pitkin County, Colorado, 26 Jul 1978.
Pileus 2-3.5 cm broad, obtuse to convex, becoming broadly convex to plane or the margin remaining decurved, slightly viscid, margin
thinly coated with grayish fibrils, disc glabrous and "Warm Sepia" to
"Vinaceous-Brown," margin gradually glabrescent. Context watery
brown when moist, pallid when faded; odor and taste mild; FeSO4
staining base of stipe blackish.
Lamellae + broad, close, adnate, about "Sayal Brown" when
mature, crisped at times, not beaded and not spotted.
Stipe 2-4 cm long, 3-6 mm thick, equal, grayish when young
from a coating of veil fibrils which leave a faint subapical zone in