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

Appendix

181

KOH, in Melzer's slowly + reddish tawny; shape ellipsoid to ovoid or
in profile tending to be obscurely inequilateral.
Hymenium.-Basidia 4-spored, 7-10 JIm broad near apex. Pleurocystidia none. Cheilocystidia fusoid-ventricose to + cylindric, 35-54
x 7-10 x 5-6 VLm for the former, for the latter 47-63 x 5-7 yRm, apex
obtuse and many with a refractive wall thickening in the interior of the
apex.
Lamellar and pilear tissues.-Gill trama typical for the genus but
in Melzer's solution the hymenium orange-ochraceous or reddish
orange but soon fading. Cuticle of pileus a well-defined ixocutis, the
hyphae 1.5-3 (Im diam and outer wall + gelatinized, no dextrinoid
debris noted. Clamps present. Hypodermium intermediate in type, +
clay color in KOH, ~ reddish brown in Melzer's, incrustations lacking.
Tramal hyphae typical for the genus.
Habit, habitat, and distribution.-On a freshly burned-over area,
Washtenaw County, Michigan, May 1, 1964 (type, MICH).
Observations.-The habitat, ordinarily, is humus under low moist
hardwoods, and the fruiting bodies were produced in an area of about
the size of an acre. Hundreds of them were present. The burn was
about a month old at the time. We at first classified this material as H.
fastibile. The veil is buff colored, the spores are a trifle large, and the
habitat and time of fruiting make identification with H. fastibile doubtful. It differs from H. pseudofastibile by its occurrence on a fresh burn
in a low hardwood forest lacking any conifers, in the gill edges not
being beaded, in having a buff-colored veil, and in the stipe not splitting into longitudinal segments.
111. Hebeloma urbanicola sp. nov. (r)
Pileus 1.5-3 cm latus, obtuse campanulatus, ad marginem fibrillosus, glabrescens, subviscidus, cinnamomeus, tarde + spadiceus.
Contextus pallide brunneus, fragilis; odor et gustus mitis. Lamellae
confertae, adnatae demum sinuatae, subdistantes, pallidae dein cinnamomeae. Stipes 2.5-4 cm longus, 2-3.5 mm crassus, albidus, demum
brunneus. Velum fibrillosum, pallidum. Sporae 7-9 x 4.5-5 txm, non
dextrinoideae, + ellipsoideae, + leves, in "KOH" subhyalinae. Basidia tetraspora. Cheilocystidia 26-37 (44) x 6-9 x 3-5,pm, clavata
vel subfusoide ventricosa (collum angustum).
Specimen typicum in Herb. Univ. Mich. conservatum est, Smith
34233; legit sub Piceae, in Ann Arbor, Michigan, 7 Oct 1949.
Pileus 1.5-3 cm broad, obtusely campanulate to expandedumbonate, margin incurved and at first fringed with veil remnants,
hoary at first from a thin coating of veil fibrils, glabrescent and ~ "Sayal