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

174

The Veiled Species of Hebeloma

expanding to plane or plano-umbonate, surface thinly viscid, pale
dingy vinaceous-cinnamon overall in age, when young the disc "Verona Brown" and the margin paler and with only a few traces of veil
remnants along it. Context pallid, odor and taste strongly raphanoid;
FeSO4 staining context and stipe olive.
Lamellae very pale dingy vinaceous-cinnamon at first, near "Verona Brown" in age, close, depressed-adnate, moderately broad, edges
pallid, not beaded and not stained.
Stipe 6-10 cm long, 4-9 mm thick, equal, splitting readily, solid,
becoming tubular, silky to scurfy-fibrillose below, pruinose-scurfy
above, not discoloring appreciably at the base and when dried concolorous with the pileus margin. Veil fibrillose, very thin, pallid.
Spores 8-10 x 5-5.5 [Lm smooth under high-dry objective, ellipsoid to ovoid, pale ochraceous in KOH and about the same in Melzer's
but finally slightly redder (not dextrinoid).
Hymenium.-Basidia 4-spored, 8-10 Vxm broad near apex, in
mass orange-red in Melzer's fading slowly to orange-ochraceous. Pleurocystidia none. Cheilocystidia fusoid-ventricose and 33-47 x 7-12
JIm or cylindric and up to 70 x 5-6 VIm, apex obtuse, thin-walled and
hyaline in KOH mounts.
Lamellar and pilear tissues.-Gill trama typical for the genus but
the subhymenium orange-red in Melzer's. Cuticle of pileus a distinct
ixocutis, hyphae 1.5-2.5 Im diam, walls highly refractive, clamps present, no dextrinoid debris evident. Hypodermium hyphoid, with scattered "cells" present, pale clay color in KOH, in Melzer's slightly
more reddish brown and dextrinoid debris present. Tramal hyphae
typical of the genus, mostly not highly colored in Melzer's or (near the
hymenium) yellowish. Clamp connections present.
Habit, habitat, and distribution.-Clustered to gregarious or scattered on sandy soil under spruce, Hell, Michigan, October 20, 1967
(type, MICH).
Observations.-This species is quite similar to H. pascuense,
hence the species epithet. It differs in the reddish brown pileus when
young, the readily splitting stipe, the colored hypoderm (in KOH), the
strong raphanoid odor and taste and the vinaceous-cinnamon gills
when young.
105. Hebeloma pseudomesophaeum sp. nov. (1)
Pileus 3-5 cm latus, obtusus demum late expansus, hygrophanus,
subviscidus, ad marginem fibrillosus vel adpresse squamulosus, fulvus
demum cinnamomeus; odor + pungens; gustus mitis. Lamellae latae,
adnatae, confertae, pallide cinnamomeae demum subfulvae. Stipes 3-6
cm longus, 3-7 mm crassus, sursum pallidus, deorsum subfulvescens;