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

Sporae 7-9.5 x 5-6 rm, ovoideae vel obscure inequilaterales, subdextrinoideae. Cheilocystidia 40-60 x 4-5 Jim, ventricosa vel filamentosa.
Specimen typicum in Herb. Univ. Mich. conservatum est, Smith
17096; legit prope Port Angeles, Washington, 21 Sep 1941.
Pileus 2-6 cm broad, obtuse and with an incurved margin at first,
expanding to nearly plane with a wavy margin and obtuse umbo, the
margin rarely uplifted, marginal area with scattered patches of appressed fibrils from the remains of the veil, surface viscid and fibrillosestreaked beneath the slime, glabrescent in age, "Cinnamon" on disc and
paler over the margin, becoming dingy clay color on disc and near
"Avellaneous" (grayer) along the margin, disc darker when watersoaked. Context thick (about 6 mm), tapered evenly to cap margin,
pliant, watery avellaneous, odor pungent, taste slightly raphanoid.
Lamellae only moderately broad but becoming slightly ventricose
(5-6 mm), close, depressed-adnate or with a slight tooth, 1-3 tiers of
lamellulae, pale avellaneous at first becoming "Sayal Brown" in age,
staining darker on the edges where injured, edges becoming eroded,
not beaded.
Stipe 5-8 cm long, 8-12 mm thick, equal or narrowed downward,
hollow, pallid in cortex, surface coarsely appressed or ragged-fibrillose
from the bicolored veil featuring an argillaceous outer and a white
inner layer; surface pallid near apex, cinnamon-buff over the remainder and becoming bister from the base upward; annular zone
evanescent.
Spores 7-9.5 x 5-6 Rxm, ovate to elliptic in face view, elliptic to
slightly bean-shaped or obscurely inequilateral in profile, smooth under
a high-dry objective, very minutely marbled under oil-immersion lens,
nearly hyaline in KOH, reddish tawny in Melzer's (but not truly dextrinoid).
Hymenium.-Basidia 4-spored, 20-24 x 7-8 Jim. Pleurocystidia
none. Cheilocystidia narrowly fusoid-ventricose, 40-60 x 6-9 x 4-5
Jim, some filamentous in age, thin-walled, hyaline in KOH.
Lamellar and pilear tissues.-Lamellar trama typical for the genus. Cuticle of pileus an ixocutis of hyphae 2-4 Jim diam, walls refractive and clamp connections present. Hypodermium hyphoid, when
fresh nearly hyaline in KOH. Tramal hyphae typical for the genus.
Habit, habitat, and distribution.-Gregarious to subcaespitose
near conifers, Mt. Angeles, Port Angeles, Washington, September 21,
1941 (type, MICH).
Observations.-The bicolored veil with remains copious enough
to cause the stipe to be ragged-fibrillose below the veil line, the relatively thick stipe for a species in this group, and the generally dingy
cinnamon color of the pileus are distinctive.