The North American species of Psathyrella.

282

MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

[VOL. 24

Observations. The white stipe, chestnut-colored pileus and medium-small
spores very pale when first revived in KOH are distinctive. The species appears
to be related to P. hymenocephala but has darker colors and lacks a veil.
242. Psathyrella subhyalinispora A. H. Smith, sp. nov.
Pileus (0.5-)1-2 cm latus, demum convexus, glaber, luteo-brunneus; lamellae
confertae, latae, pallidae demum fusco-brunneae; stipes 2-5 cm longus, 1-2 mm
crassus, fragilis, albidus, nitens, sursum pruinosus; velum nullum; sporae 7-9 X
4.5-6,/; in "KOH" subhyalinae; pleurocystidia nulla; fibulae adsunt. Typus.
Hesler 23083 (MICH); legit Knoxville, Tennessee.
Pileus (0.5-)1-2 cm broad, obtusely conic to convex, scarcely expanding,
glabrous, moist, hygrophanous, dingy yellow-brown moist, pallid olivaceous faded
but drying pale dull cinnamon, striate to disc when moist, atomate when faded.
Context pallid, fragile, odor and taste mild.
Lamellae adnate to adnexed, close, moderately broad, soon seceding, pallid
when young, "wood brown" mature, dull cinnamon when dried, edges even.
Stipe 2-5 cm long, 1-2 mm thick, equal, fragile, hollow, white and shining,
apex pruinose, naked lower down. Veil none.
Spores "hair brown" to "drab" in a deposit, 7-9 x 4.5-6 /, smooth, apical pore
not distinct, shape in face view ovate to elliptic, in profile obscurely to somewhat
inequilateral, color in KOH subhyaline (dilute brownish under microscopeHesler), yellowish in Melzer's, wall -0.2 /u thick.
Basidia 4-spored, (10-) 12-18 x 7-10,u, subglobose to broadly clavate, hyaline
in KOH. Brachybasidioles present, 9-11, wide. Pleurocystidia none. Cheilocystidia clavate to utriform-much as in P. hymenocephala, hyaline to yellowish
in KOH.
Gill trama yellowish-hyaline in KOH, hyphal cells greatly inflated, hyphae
interwoven; subhymenium of large (8-15 /u) inflated cells. Pileus cuticle of greatly
inflated cells (up to 60,), yellowish-hyaline in KOH, thin-walled, hyphae of
subcuticular region yellowish-hyaline in KOH, walls smooth. Clamps present.
Type locality. Knoxville, Tennessee.
Habit and habitat. Gregarious on humus, May.
Distribution. Known only from type locality.
Observations. This species has the stature of Pseudocoprinus disseminatus but
appears to be closely related to Psathyrella singeri. In fact it is one of a "cluster"
of species, mostly southern in distribution, with pale colored spores in KOH.
243. Psathyrella hoseneyae A. H. Smith, sp. nov.
Pileus 1-4 cm latus, campanulatus, cacaocolor, glaber; contextu cacaocolor;
lamellae angustae, confertae, brunneolae demum cacaocolor; stipes 3-6 cm longus,
2-4 mm crassus, pallidus, sursum pruinosus, deorsum glaber; sporae 6-7 x 4-4.5 u;
pleurocystidia nulla; fibulae adsunt. Typus. Hoseney 90 (MICH); legit prope
Ann Arbor, Michigan.
Illust. Text Figs. 538, 539.
Pileus 1-4 cm broad, obtusely conic expanding to broadly conic or broadly
campanulate, more or less of a rich cocoa-brown when young, becoming paler
(dull cinnamon-tan) and finally grayer as the spores mature, a dull alutaceous as
dried, glabrous, margin naked and appressed against the stipe when young, not