The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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290. Psathyrella ruderaria A. H. Smith, sp. nov.
Pileus 1-2.5 cm latus, obtuse conicus vel late convexus, glaber, cinnamomeus
demum griseo-violaceus; contextu fumoso-cinnamomeus; lamellae confertae,
latae, brunneolae demum fumoso-cinnamomeae; stipes 2.5-6 cm longus, 1-2 mm
crassus; deorsum brunneus, glaber; sporae 9-12 x5-6 t; pleurocystidia (36-)
48-76 x9-16 tu, fusoide ventricosa obtusa vel subacuta; fibulae adsunt. Typus.
Smith 51661 (MICH); legit prope Placerville, Colorado.
Pileus 1-2.5 cm broad, obtusely conic expanding to broadly convex, surface
glabrous, moist, hygrophanous, dingy cinnamon when young, becoming wood
brown and finally "benzo brown," buffy avellaneous faded, distinctly atomate,
drying more or less dingy cinnamon ("Sayal brown"). Context very thin and
fragile, dark cinnamon when moist, odor and taste not distinctive.
Lamellae close, moderately broad, adnate, dingy brownish at first, becoming dull cinnamon and finally darker from the spores, drying dark grayish brown.
Stipe 2.5-6 cm long, 1-2 mm thick, equal, fragile, pallid above, brownish below,
glabrous and naked, dull tan over all when dried.
Spores 9-12 x 5-6 A, smooth, in a profile view the small pore slightly oblique
and apex not truncate, shape in face view broadly elliptic to obscurely ovate, in
profile subelliptic to obscurely inequilateral, color in KOH dark russet-brown soon
becoming chocolate-color, in Melzer's tawny-red, wall about 0.4,u thick (in KOH).
Basidia 4-spored, subellipsoid to clavate, 14-18(-22)x 10-13 /x, hyaline in
KOH. Pleurocystidia (36-) 48-76 x 9-16 p, fusoid-ventricose, neck becoming
greatly elongated, apex obtuse (but narrow) to subacute, wall thin, smooth and
hyaline, cell content not distinctive. Cheilocystidia 32-43 x9-13,u, fusoid to
fusoid-ventricose, apex subacute to obtuse, thin-walled, smooth. Pileus cuticle of
inflated cells up to 20 A wide, the layer 2-3 cells deep, walls hyaline to pale cinnamon, smooth. Hyphae of the subcutis vinaceous-cinnamon in KOH, walls incrusted but not conspicuously so. Clamps present.
Type locality. Placerville, Colorado.
Habit and habitat. Gregarious around piles of organic debris.
Distribution. Colorado.
Observations. The lack of a veil, medium-sized spores, pleurocystidia with
greatly elongating necks and the generally cinnamon-colored basidiocarps as
dried are distinctive.
291. Psathyrella nitens A. H. Smith, sp. nov.
Pileus 2-3.5 cm latus, late convexus, sparse fibrillosus vel floccosus, glabrescens; subspadiceus; contextu dilute brunneus; lamellae confertae angustae,
avellaneae demum griseo-violaceae; stipes 5-8 cm longus, 2-3.5 mm crassus,
albidus, undulatus, fibrillosus, glabrescens; sporae 9-10.5 x 5-6.3 /; pleurocystidia
48-62 x 10-15 /, fusoide ventricosa obtusata; fibulae adsunt. Typus. Smith 30388
(MICH); legit prope Tahoma Creek, Mt. Rainer National Park, Washington.
Illust. Text Figs. 630-632.
Pileus 2-3.5 cm broad, convex, becoming nearly plane, surface at first thinly
covered with white fibrils from the outer veil, the fibrils becoming aggregated into
minute flecks and soon vanishing, margin slightly fringed at first, surface moist
and hygrophanous, between buckthorn brown and cinnamon-brown when moist
and when faded pale cinnamon-buff, but drying a dark dull brown. Context thin
and fragile, watery brown moist, odor not distinctive, taste not noted.