The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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160. Psathyrella longicystis A. H. Smith, sp. nov.
Pileus 8-12 mm latus, convexus, dilute cinnamomeo-brunneus, dein triste
brunneo-griseus; fibrilloso-floccosus, glabrescens; lamellae latae adnatae, demum
subdistantes, brunneolae demum violaceo-brunneae (fuscae); stipes 4-6 cm
longus, 1 mm crassus, pallidus, deorsum fibrillosus, glabrescens; sporae 9-12x
6-7 ji; pleurocystidia 50-80x 10-15 a, fusoide ventricosa; fibulae adsunt. Typus.
Smith 33683 (MICH); legit prope Burt Lake, Michigan.
Illust. Text Figs. 358-360.
Pileus 8-12 mm broad, convex, moist and hygrophanous, pale cinnamon-brown
when young, drab-gray to pale fuscous when mature, surface at first covered by
delicate pallid flecks of fibrils representing remains of an outer veil. Context very
membranous-fragile, no odor evident, taste not recorded.
Lamellae broad, broadly adnate, close becoming subdistant, brownish when
young fuscous when mature, edges whitish.
Stipe 4-6 cm long, about 1 mm thick, whitish to dingy but not distinctly
darkening in the lower portion, pruinose above, at first fibrillose below from the
remains of the veil, glabrescent, very fragile and delicate.
Spores 9-12 x6-7 j, smooth, apical pore present but inconspicuous and the
apex rounded, shape in face view broadly ovate to broadly elliptic, in profile
subelliptic to obscurely inequilateral, color in KOH dull cocoa-color darkening
to dark chocolate-color, in Melzer's rich tawny, wall about 0.4 p thick.
Basidia 4-spored, 20-35 x 9-12 i, elongate-clavate to merely clavate, hyaline
in KOH. Brachybasidioles not differentiated. Pleurocystidia abundant, 50-80 x
10-15 A, ventricose near base, with a greatly elongated neck and apex obtuse, wall
thin, smooth and hyaline, cell content not distinctive in KOH or in Melzer's, apex
in some forked or with protuberances. Cheilocystidia similar to the pleurocystidia
but smaller.
Gill trama ochraceous in KOH, regular, cells inflated. Pileus trama of hyphae
with rich rusty brown walls in KOH with distinct pigment incrustations; the
cuticle of inflated cells 2-3 deep and having yellowish to hyaline, thin, smooth
walls, cell content not distinctive in KOH or Melzer's. Clamp connections present.
Type locality. Colonial Point, Burt Lake, Cheboygan County, Michigan.
Habit and habitat. On decaying leaves of beech-maple forest.
Distribution. Known only from type locality.
Observations. The aspect of the basidiocarp is that of the P. gracilis group
but the outer veil and the forked condition of many of the pleurocystidia along
with the rather obscure apical pore of the basidiospores indicate otherwise.
161. Psathyrella salictaria A. H. Smith, sp. nov.
Pileus 1-2.5 cm latus, conicus, demum campanulatus, sparse fibrillosus, glabrescens, griseo-cinnamomeus; lamellae confertae, latae, cinnamomeo-brunneae,
demum griseo-fuscae; stipes 3-5 cm longus, 1-1.5 mm crassus, sparse fibrillosus,
glabrescens, sordide brunneus sed ad apicerum pallidus; sporae 9-12 x 5-6 /;
pleurocystidia 37-54 x8-14,/, fusoide ventricosa, acuta vel subacuta; fibulae
adsunt. Typus. Smith 66291 (MICH); legit prope Burgdorf, Idaho.
Illust. Text Figs. 361-364.
Pileus 1-2.5 cm broad, obtusely conic becoming obtusely umbonate, moist and
hygrophanous, color a grayish cinnamon-brown, when moist translucent striate
half way to disc, at first with scattered fascicles of pallid fibrils over marginal