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

The Subgenus Hebeloma

157

rocystidia none. Cheilocystidia 33-52 x 7-9 pLm, slightly ventricose
near the base, neck with wavy walls and apex obtuse, thin-walled,
smooth.
Lamellar and pilear tissues.-Lamellar trama typical for the genus. Cuticle of pileus a subixocutis (slime quickly soluble in KOH),
hyphae 3-5 tm diam, tubular, clamps present. Hypodermium not distinct from pileus context.
Habit, habitat, and distribution.-Gregarious to scattered under
herbaceous vegetation (weeds) in a spruce seepage area, Burnt Mt.,
Pitkin County, Colorado, July 18, 1976 (type, MICH).
Observations.-The date brown pileus, pallid buff veil, the +
inequilateral spores in profile view, and lack of a differentiated hypodermium are a distinctive combination of features.
91. Hebeloma praelatifolium sp. nov.
Pileus 1-2.5 (3) cm latus, late convexus, viscidus, glaber, cinnamomeo-brunneus ("Cinnamon-Brown"), ad marginem pallidior; odor et
gustus mitis. Lamellae perlatae et ventricosae, adnatae, distantes vel
subdistantes, griseae demum cinnamomeae. Stipes 3-5 cm longus, 1.5-2
mm crassus, flexuosus griseofibrillosus, deorsum demum obscure brunneus. Basidia tetraspora. Sporae 11-14 x 6.5-7.5 pm, non dextrinoideae. Cheilocystidia 37-52 x 7-11 x 4-6 pm, fusoide ventricosa demum
+ filamentosa, vel 40-60 pm longa, filamentosa.
Specimen typicum in Herb. Univ. Mich. conservatum est, Smith
89109; legit prope Savage Lakes, Pitkin County, Colorado, 23 Aug
1978.
Pileus 1-2.5 (3) cm broad, broadly convex, becoming plane and
in some the margin paler, fading to tawny around the disc and the
margin to pinkish buff, opaque when faded, viscid. Context very thin
and pallid, odor and taste mild, FeSO4 staining the base of the stipe
olive-fuscous.
Lamellae broad and ventricose, adnate, distant to subdistant,
grayish at first (+ "Avellaneous"), at maturity pale cocoa-brown, at
most slightly beaded.
Stipe 3-5 cm long, 1.5-2 mm thick, equal, flexuous, surface coated with pale gray fibrils of a thin veil which soon vanishes; base becoming dark brown and the color progressing upward to the + pallid
apical region.
Spores 11-14 x 6.5-7.5 pam, + clay color in KOH, pale tawny in
Melzer's (nondextrinoid), very faintly marbled (mounted in Melzer's),
shape in profile + inequilateral, in face view ovate to subelliptic, the
apex blunt.