The North American species of Psathyrella.

56 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [VOL. 24
Gill trama regular, cells inflated, thin-walled, smooth and hyaline in KOH.
Pileus with a cuticle of vesiculose cells 10-18 p wide and 3-6 cells deep, the walls
thin, smooth, hyaline in KOH, content not distinctive in KOH or Melzer's. Veil
remnants often forming a thick layer (about 300 pt thick) of interwoven hyphae
7-12 M wide and having thin, smooth, hyaline walls in KOH and regularly with
clamps. Hyphae of the pileus trama hyaline in KOH and with smooth walls.
Hyphae of the stipe cortex with an uneven wall giving the impression of roughness
but the walls often refractive enough to obscure fine detail.
Type locality. Lower Tahoma Creek, Mt. Rainier National Park, Washington.
Habit and habitat. Cespitose on dead alder stubs and logs, fall.
Distribution. Washington.
Observations. This species is related to P. lacrymabunda but the spores distinguish it as do the color changes in the veil on aging. The pleurocystidia are
more diverse and none was found with amyloid content. It might also be compared with P. scobinacea (Fr.) Singer, but the buttons are white at first.
Material examined. Washington: Smith 29308, 29505 (Type), 29916, 30360,
30421,30591,30687.
21. Psathyrella maculata (Parker) Moser in Gams, Kleine Krypt. Fl. Europa.
243. 1955.
Hypholoma maculatum Parker, Mycologia 25: 205. 1933.
Illust. P1. 13, fig. b; P1. 14; Text Figs. 49, 51, 52.
Pileus 2-6 cm broad, obtuse when young, expanding to obtusely campanulate
and finally plane or with a slight umbo, surface at first viscid from a "mummy
brown" (blackish brown) to pale grayish brown coating of outer veil remnants,
the pallid grayish brown fibrils of the pileus cuticle soon showing through, at
maturity with a broad mummy brown patch or patches or streaks and with pale
avellaneous to dark wood brown appressed fibrils over the remainder, margin
typically appendiculate with pallid to wood brown cottony triangular patches of
veil remnants. Context soft, fairly thick, whitish and unchanging, taste mild, odor
fungoid.
Lamellae crowded, narrow, depressed-adnate, pallid when young, "cinnamondrab" in age, edges white floccose.
Stipe 6-12 cm long, 6-14 mm thick at apex, slightly narrowed downward,
fleshy and fibrous (not fragile), solid becoming hollow, pallid within but pinkish
in the base when cut, surface densely fibrillose and lower part entirely covered
or merely streaked with mummy brown fibrils, pallid near the apex, some with an
apical annulus and surface above it fibrillose scurfy.
Spores 5-6 x 3-3.5,, smooth, apical pore present but very inconspicuous, in
face view elliptic to oblong, in profile more or less bean-shaped, color in KOH
moderately dark chocolate-color, in Melzer's reddish tawny, wall thin.
Basidia 14-18(-20) x4.5-7 /u, 4-spored, narrowly clavate, hyaline in KOH.
Pleurocystidia abundant, 32-46 x 9-15 A, obovate-mucronate or the apical fingerlike prolongation considerably drawn out (up to 6-15 / long), walls thin, smooth
and hyaline, content homogeneous in KOH or rarely with a few refractive particles, homogeneous in Melzer's. Cheilocystidia similar to pleurocystidia or merely
saccate and up to 18-20 p wide. Caulocystidia mostly elongate-clavate to short
clavate, oval or obscurely cystidioid, smooth and hyaline, content not distinctive.
Pileus with a cuticle of inflated cells 3-4 deep, walls thin, hyaline and smooth,
content not distinctive in either KOH or Melzer's; hyphae arising from between