The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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Distribution. Known only from the type locality.
Observations. Smith (1934) identified this material as P. hirta Peck but this
was a mistake. The latter is coprophilous. The abortive bodies (carpophoroids)
are smaller than those of Rhodophyllus abortivus but are of the same consistency.
Material examined. Michigan: Smith, Oct. 1932, 33-1099 (Type).
158. Psathyrella monticola A. H. Smith, sp. nov.
Pileus 8-15 mm latus, conicus, demum late conicus, subcacaocolor, sparse
fibrillosus, glabrescens, ad marginem fimbriatus, glabrescens; lamellae brunneolae, demum subcacaocolor, latae, subdistantes; stipes 1.5-2 cm longus, 1-1.5 mm
crassus, dilute alutaceus; sparse fibrillosus; sporae 9-11.5x5.5-7x4.5-5.5 U;
pleurocystidia 34-45x10-16 /A, late fusoideo-ventricosa, obtusa vel subacuta;
fibulae adsunt. Typus. Smith 65132 (MICH); legit prope New Meadows, Idaho.
Illust. Text Figs. 352-354.
Pileus 8-15 mm broad, obtusely conic, the margin straight, expanding to
broadly conic to almost convex, surface moist and hygrophanous, near "Verona
brown" (dull cinnamon) moist, fading to dingy cinnamon-buff, surface at first
covered with a thin layer of superficial white fibrils from an outer veil and the
margin delicately appendiculate-fringed, both margin and surface glabrous by
maturity, when moist opaque or only weakly striatulate. Context thin and fragile,
odor and taste none, concolorous with surface either when moist or faded.
Lamellae brownish at first ("pinkish buff"), when mature dingy cocoa-color,
broad, adnate, seceding, subdistant, edges even.
Stipe 1.5-2 cm long, 1-1.5 mm thick, equal, watery cinnamon-buff over all,
at first faintly fibrillose from the pallid veil but soon glabrescent, (no zones or
patches of veil material evident).
Spores 9-11.5 x 5.5-7 x 4.5-5.5 g, smooth, truncate from an apical pore, compressed slightly, in face view broadly ovate to elliptic, in profile very obscurely
inequilateral (plage area flattened slightly) to subelliptic, color in KOH dark
chocolate-color, in Melzer's dark bay-red, wall about 0.5 / thick.
Basidia 4-spored, 23-30 x9-12 pg, hyaline in KOH. Pleurocystidia scattered,
34-45 x 10-16 a, broadly ventricose with a short neck and obtuse to subacute apex,
walls thin and smooth, content not distinctive, the cystidia collapsing and difficult
to revive. Cheilocystidia covering the gill edge, vesiculose, to broadly fusoidventricose, thin-walled, smooth, hyaline or content in some smoky vinaceousbrown. Caulocystidia absent to rare and resembling cheilocystidia (an occasional
inflated hyphal end cell). Hyphae of stipe cortex weakly vinaceous-brown in
KOH when seen collectively.
Cuticle of pileus a layer of inflated and pedicellate cells 1-2 deep, the base of
the pedicels often with thickened (0.5 g) colored walls in KOH. Subcuticular
layer of tubular to inflated hyphal cells, the layer dark vinaceous brown in KOH
but fading, hyphal walls roughened somewhat. Context hyphae also vinaceousbrown in KOH but fading. Clamps present. No distinctive reaction with Melzer's
on any tissue.
Type locality. Goose Lake, New Meadows, Idaho.
Habit and habitat. On earth in an old burn, July.
Distribution. Known only from the type locality.
Observations. This species is distinguished by the slightly compressed spores,
the short broad pleurocystidia, the numerous vesiculose cheilocystidia, the thin
veil and the dingy honey-colored stipe. It is questionable if the habitat is sig