The North American species of Psathyrella.

1972]

PSATHYRELLA

35

3. Psathyrella sepulchralis Singer, Smith & Guzman Huerta, Lloydia 21: 26. 1958.
Psathyrella sepulchrorum (Singer, Smith & Guzman) Singer, Agar. Modern Taxon. 507.
1963.
Illust. 1.c. fig. 1. Text Figs. 1-4.
Pileus 7-9 cm broad, broadly campanulate to broadly conic, margin appendiculate from the broken veil, surface fibrillose-squamulose to appressed fibrillose
with the fibrils often in fascicles, fibrils dark brown (reminding one of those of
P. echiniceps), ground color orange-brown, deeper colored over the disc. Context
whitish, odor farinaceous to lacking.
Lamellae sinuate, close, narrow to only moderately broad, grayish becoming
dark purple-brown, finally blackish-mottled, edges pallid-fimbriate.
Stipe 14-26 cm long, 5-10 mm wide, slightly enlarged downward, squamulose
or variously ornamented with dark fibrils similar to those on pileus, ground
color a little paler than that of pileus and in the cortex brownish, apical region
whitish, smooth, silky fibrillose from fine appressed fibrils.
Spores black in deposit, 10-12.5(-13.5) x8.5-10.5 u, coarsely verrucose and
with a hyaline bubble-like apical "pore," in face view broadly elliptic (excluding
the apical pore), in profile broadly inequilateral, color in KOH blackish brown, in
Melzer's blackish brown due to the dark colored ornamentation, dark bay red for
the ground color, wall about 0.3 / thick.
Basidia 22-38 x 7-9 /A, hyaline to pale fuscous in KOH, 4-spored, projecting to
different lengths when sporulating. Pleurocystidia in scattered fascicles, 40-60 x
9-15 /A, utriform to broadly fusoid-ventricose with obtuse apex, content hyaline
to pale fuscous in KOH, walls thin and smooth. Cheilocystidia abundant, 38-70 x
8-11 g, hyaline to pale fuscous, elongate-clavate to slightly ventricose and with
the apical region oval to subcapitate or abruptly pointed. Caulocystidia 40-100 u
long, clavate, fusoid-ventricose with obtuse apex, or subfilamentous-capitate,
smooth, thin-walled, hyaline, content not distinctive.
Gill trama subparallel, the hyphae with pale fuscous-brown walls as revived
in KOH; subhymenium more darkly colored than the central area because of the
narrower cells. Pileus with a cuticle of inflated cells 3-4 cells deep and their
walls dull ochraceous in KOH, smooth and 0.5 gA thick; fascicles of dark fibrils
composed of hyphae 8-12, wide with ochraceous thickened (0.5-1 g) walls in
KOH and wall outline uneven from adhering material. Hyphae of the context
as revived in KOH hyaline to brownish. Clamp connections regularly present. No
distinctive iodine reactions on any cell or tissue, but in KOH dark brown
basidiole-like bodies are numerous in the hymenium.
Type locality. Near San Agustin Loxicha, Oaxaca, Mexico.
Habit and habitat. Solitary on soil under herbaceous plants.
Distribution. Mexico.
Observations. This species is distinct because of the coarse spore ornamentation which becomes darker brown in Melzer's, and the dark colored hairs on the
pileus. It is obvious that ecologically the species occupies a niche similar to that
of P. velutina. The ornamentation of the pileus reminds one of P. echiniceps.
4. Psathyrella echiniceps (Atkinson) A. H. Smith, comb. nov.
Hypholoma echiniceps Atkinson, Ann. Mycol. 7: 370. 1909.
Illust. P1. 2; Text Figs. 5-7.
Pileus 3-10 cm broad, obtuse to convex, becoming subumbonate to nearly
plane, in age the margin usually spreading but at times recurved slightly, surface