The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

[VOL. 24

a very narrow zone of narrow hyphae with short cells, the zone often rather
indistinct as revived in KOH. Cuticle of pileus of vesiculose cells in a layer
3-4 deep, the walls thin and hyaline and the cell content not distinctive. Hyphae
of the subcutis brownish in KOH on mature pilei (possibly hyaline at first),
smooth, lacking distinctive content. Clamp connections present.
Type locality. Near the old town of Emerson, Michigan in Chippewa
County.
Habit and habitat. Gregarious on decaying hardwood log, August.
Distribution. Known only from the type locality.
Observations. The collection was made by Mr. Walter Litten of Rochester,
New York. The species is amply distinct by virtue of its narrow, crowded
lamellae, very short pleurocystidia which when revived in KOH have the curious
content of refractive particles, and the dull red spore deposit. The large size of
the cheilocystidia is also unusual in this section. A variant with broad gills and
growing on old conifer logs occurs in Idaho (Smith 65095). The inclusions and
incrustations of the cystidia do not react in NH,OH.
198. Psathyrella spadicea (Fries) Singer, Lilloa 22: 468. 1951.
Agaricus spadiceus Fries, Epicr. Syst. Mycol. 225. 1838.
Psilocybe spadicea (Fr.) Kummer, Fiihr. Pilzk. 71. 1871.
Drosophila spadicea (Fr.) Quelet, Enchir. Fung. 116. 1886.
Pratella spadicea (Fr.) Schroeter, Krypt. Fl. Schles. 3: 568. 1889.
Illust. P1. 65; P1. 68, fig. a; Text Figs. 456-458.
Pileus 3-6 (-10) cm broad, obtuse to convex when young, the margin inrolled
and naked, expanding to obtusely umbonate, broadly convex or nearly plane
with the margin often undulating or wavy, sometimes irregular in outline from
mutual pressure, moist, glabrous and smooth, hygrophanous, when moist pale date
brown to pale or dark chocolate-brown, when faded pallid alutaceous, often
irregularly cracked in age. Context thin but rigid and firm, becoming fragile
finally, odor and taste not distinctive.
Lamellae adnate to sinuate, narrow but finally becoming moderately broad,
crowded, pallid at first, soon tinged incarnate and finally dark purple-brown
from the spores, edges usually white-floccose.
Stipe 4-8 (-12) cm long, 4-10 (-12) mm thick, stuffed becoming hollow, equal or
slightly enlarged below, straight to somewhat curved, somewhat fleshy but rigid
and brittle, pruinose above, somewhat silky-striate toward the base, base more
or less white-mycelioid, white over all or in age discoloring to dingy reddish
brown at least near the base; no veil present.
Spore deposit "fawn color" to "wood brown" (dark grayish brown). Spores
7-9 (-10) x 4-5.5 A, smooth, apical pore not evident except under very high power
oil-immersion and then visible only in an optical section of the spore, shape in
face view ovate to elliptic to oblong, in profile obscurely inequilateral to somewhat bean-shaped, color in KOH singly nearly hyaline but with a vinaceous
tint, on standing the vinaceous tint duller and stronger (spores in small groups
pale cocoa-color), in Melzer's pale tan to pale reddish tawny, wall about 0.2 /
thick (as mounted in KOH).
Basidia 4-spored, 18-24 x 5-8 /, clavate, hyaline in KOH. Pleurocystidia
abundant, 36-58 (-67) x 9-15 (-18) La, broadly fusoid, apex acute to subacute, wall
up to 2-3,u thick in the neck near the apex and the latter often variously incrusted, otherwise the wall smooth, content not distinctive in KOH or in Melzer's.
Cheilocystidia similar to pleurocystidia or broader and shorter, also numerous