The North American species of Psathyrella.

1972]

PSATHYRELLA

141

fusoid-ventricose with broadly rounded to obtuse apex, thin-walled, hyaline,
smooth, cell content not distinctive. Cheilocystidia mostly clavate to vesiculose
and yellow in KOH.
Gill trama with a rusty brown central strand in KOH, the hymenopodial area
hyaline. Pileus cuticle 2-3 cells deep, of inflated cells with ochraceous walls in
KOH, smooth. Hyphae of subcuticular region rusty brown in KOH, with incrustations on the walls. Clamp connections present.
Type locality. Pole Mountain, Albany County, Wyoming.
Habit and habitat. Cespitose on soil in a mixture of aspen and conifers, May,
alt. 8,000 ft.
Distribution. Known only from type locality.
Observations. This species has spores which in face view suggest very much
those of P. hirtosquamulosa in shape but are much darker in color. The species
is most closely related to P. ophirensis. It needs to be critically described from
fresh material but is worth putting on record here because of the shape of the
spores in face view.
95. Psathyrella renispora A. H. Smith, sp. nov.
Pileus 3-6 cm latus, convexus demum late convexus, castaneus, ad marginem
sparse appendiculatus; lamellae confertae, angustae vinaceo-brunneae; stipes
4-8 cm longus, 3-5 mm crassus, pallidus, sparse fibrillosus; sporae 7-10x 4-5,
reniformes; pleurocystidia 34-46 (-50) x 9-15 p., utriformia vel fusoide ventricosa,
ad apicerum obtusa; fibulae adsunt. Typus. Smith 340 (MICH); legit prope Lake
Placid, New York.
Illust. Text Figs. 236-238.
Pileus 3-6 cm broad, convex, glabrous, moist and hygrophanous, near "chestnut" (very deep chestnut-brown) when moist, fading to "walnut brown" (vinaceous-brown) when faded, margin at first decorated with particles of veil tissue
but these soon disappearing; veil thin and submembranous to fibrillose. Context
thin and fragile, dull rusty brown, odor none.
Lamellae close to crowded, narrow, adnate, dull reddish ("Vandyke brown")
and drying vinaceous-brown (almost as in P. spadicea), edges even.
Stipe 4-8 cm long, 3-5 mm thick at apex, slightly enlarged downward, hollow,
fragile, whitish becoming dull ochraceous when dried especially over the lower
portion, sparsely fibrillose from the remains of the veil.
Spores 7-10 x 4-5 l, smooth, apical pore present but indistinct, shape in face
view oblong to narrowly elliptic and some with a medial to submedial slight
constriction, in profile kidney-shaped to obscurely so, color in KOH fuscous with
a yellow tinge (near "sepia" to "mummy brown"), slowly becoming dark chocolate-color, tawny-red in Melzer's, wall about 0.3 t thick.
Basidia 4-spored, 18-28x 7-9 j, sections of hymenium distinctly ochraceous
in KOH. Pleurocystidia abundant, 34-46(-50) x9-15 t, utriform to narrowly
ventricose, tapered to an obtuse apex, wall thin, smooth and hyaline, cell content
not distinctive in KOH or Melzer's. Cheilocystidia similar to pleurocystidia or
subcylindric to saccate or vesiculose. Caulocystidia similar to pleurocystidia or
(more frequently) merely clavate to vesiculose with the wall in basal part
slightly (0.5 Iu) thickened and ochraceous in KOH.
Gill trama parallel, as revived in KOH a duller rusty brown than the
hymenium but the hyphae smooth. Pileus trama dark rusty brown in KOH
(amber brown or darker) but lacking distinctive incrustations (rarely a few