The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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ventricose above a scarcely distinct pedicel, with a thick neck and broadly
rounded subcapitate apex, or subcylindric. Cheilocystidia abundant, elongated
and with clavate to subcapitate apex, smooth, hyaline, 50-70x 10-13 /. Caulocystidia not studied.
Gill trama hyaline in KOH or slightly sordid yellowish in the subhymenium,
hyphae parallel, the cells long and broad (about 80x15 4). Pileus with the
cuticle composed of vesiculose cells several cells deep and having pale tawny
walls when revived in KOH, a few filamentous hyphae can be found projecting
from between the cells and having a faintly yellowish (in KOH) incrusting pigment and clamp connections. Context of floccose interwoven hyphae which are
pale tawny when revived in KOH.
Type locality. Ithaca, New York.
Habit and habitat. Scattered to gregarious on humus in the woods often
around stumps.
Distribution. Maryland, Michigan, New York.
Observations. In this species it is the hyaline pore-apparatus which projects
strongly to give the spore the characteristic appearance for the group. In P.
velutina there is a short tube of colored wall material with the pore at the apex.
In the field this species is readily distinguished by its glabrous rugulose pileus and
large size. The pleurocystidia are found both in fascicles and occurring singly.
Material examined. Maryland: Kelley 78,1636. Michigan: Kauffman 9-6-07,
9-28-21. New York: Type; Deegan H49; Shaffer 1285.
7. Psathyrella rigidipes (Peck) A. H. Smith, comb. nov.
Hypholoma rigidipes Peck, Bull. N. Y. State Mus. 139: 24.1910.
Drosophila rigidipes (Peck) Murrill, Mycologia 14: 70. 1922.
Illust. Peck. op. cit. pl. 3, figs. 1-6. P1. 6; Text Figs. 8-11.
Pileus 2.5-5 cm broad, convex to broadly convex, dry, fibrillose squamulose,
tawny brown, often reddish at the center. Context whitish at first, taste mild.
Lamellae close, narrow, slightly sinuate, adnexed, brownish red, becoming dark
purplish brown or black.
Stipe 5-10 cm long, 4-6 mm thick, slender, rigid, equal, hollow, fibrillosesquamulose, colored like or a little paler than the pileus.
Spores 9-12x 5-5.7 a, weakly to distinctly ornamented with small warts to
appearing almost smooth (under low-power oil immersion), apex truncate from a
broad pore but apex typically not snout-like (Fig. 9), shape in face view elliptictruncate to ovate-truncate, typically pointed at basal end, in profile somewhat
elongate-inequilateral due to the broad suprahilar depression, color in KOH dark
bister becoming dark chocolate-color, in Melzer's dull bay-red, wall about 0.2 /u
thick.
Basidia 4-spored, 20-24 x8-10 A, hyaline to (in age) weakly brownish at
base in KOH. Pleurocystidia 42-56 x 9-14 t, scattered or in fascicles, often rare,
cylindric but often flexuous, subclavate, to subcapitate or abruptly tapered to
a point at apex, walls thin, smooth and hyaline, content not distinctive in KOH
or Melzer's. Cheilocystidia 50-64x9-12 at, filamentose to subcapitate, hyaline,
thin-walled, smooth. Caulocystidia versiform (Fig. 10), thin-walled, walls yellowish to hyaline in KOH, smooth, content not distinctive.
Gill trama of parallel hyphae, the cells considerably enlarged, unusually dark
sordid yellowish-brown. Pileus with a cuticle of vesiculose cells several deep,
their walls smooth, yellowish in KOH and thin, content not distinctive; fila