The North American species of Psathyrella.

1972]

PSATHYRELLA

161

Observations. The spores distinguish this species from P. tsugae and P. subalpina-there is no tendency whatever toward a basal truncation. The very
elongated subacute pleurocystidia, lack of any apical truncation of the spores, and
occurrence on conifer wood are diagnostic. Frog Lake is near Wapinita Summit
in the Cascades south of Mt. Hood, Oregon.
Material examined. Alaska: Wells-Kempton 7-9-64-#3. Idaho: Smith
69731, 70086, 71259. Oregon: Smith 28032 (Type).
117. Psathyrella indecorosa A. H. Smith, sp. nov.
Pileus 2-5 cm latus, demum late convexus, ad centrum glaber, ad marginem
floccosus et appendiculatus, glabrescens, cinnamomeo-brunneus; lamellae latae
confertae, pallidae demum fumoso-cinnamomeae; stipes 3-7 cm longus, 2-5 mm
crassus, albidus vel pallidus, fibrilloso-floccosus, glabrescens; sporae 6.5-7.5 (-8) x
3.8-4.3,; pleurocystidia 38-60 x9-14(-16),, fusoide ventricosa, acuta; fibulae
adsunt. Typus. Smith 14272 (MICH); legit prope Lake Crescent, Washington.
Illust. Text Figs. 275-277.
Pileus 2-5 cm broad, obtuse when young, expanding to convex, slightly umbonate or nearly plane, surface glabrous over the disc, toward the margin decorated
with pallid patches of veil material and margin appendiculate with pallid submembranous patches of the veil tissue, glabrescent, rusty brown (near "cinnamonbrown") moist, fading to dingy tan, odor and taste not distinctive.
Lamellae moderately broad, close, adnate-seceding, pallid to dingy brownish
becoming dull rusty cinnamon with a smoky tinge but dark to medium cinnamon
or cinnamon-brown as dried, edges fimbriate.
Stipe 3-7 cm long, 2-5 mm thick, equal or enlarged slightly at the base,
fragile, hollow, white, not appreciably discoloring(?), at first fibrillose from
remains of a medium copious veil, apex pruinose.
Spores 6.5-7.5(-8) x3.8-4.3,, smooth, apical pore present but apex only
obscurely truncate in some spores, shape in face view obscurely wedge-shaped
to ovate or subelliptic, in profile mostly obscurely inequilateral (with ventral line
relatively straight and dorsal line humped near the apiculate end), color in KOH
dingy pale rusty cinnamon but slowly becoming chocolate-gray, in Melzer's pale
tawny with a reddish tone, wall about 0.2,u thick.
Basidia 4-spored, clavate, 16-20 x8-9 /, hyaline in KOH. Pleurocystidia
abundant, 38-60 x 9-14(-16) /L, fusoid-ventricose with apex acute, smooth, wall
thin to 0.4 u thick (in KOH) and becoming slightly refractive, neck often filled
solid with a mucilaginous content, wall hyaline, no debris adhering (a few with
a pale smoky content in KOH). Cheilocystidia mostly clavate to vesiculose and
readily collapsing, 12-18x 6-10 I, also present are numerous lanceolate-flexuous
to fusoid-ventricose cells all with acute apex and in most a slightly thickened
refractive wall.
Cuticle of pileus 1-3 cells deep, of inflated hyaline, smooth, thin-walled cells
lacking a distinctive content. Hyphae of subcuticular region reddish cinnamon
to dull tawny in KOH, the walls smooth and thin. Clamps present.
Type locality. Lake Crescent, Washington.
Habit and habitat. Subcespitose on alder logs, June.
Distribution. Idaho, Michigan, Washington.
Observations. It is almost shameful to describe another species in this group,
but this one appears amply distinct by its smooth pointed pleurocystidia, small
spores, the shape of the spore in face view (broadest near the base), and more