The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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hollow, easily splitting; veil whitish at first, evanescent, remnants sometimes
found near the base of the stipe.
Spores 9-12 (-13) x 5-7 M, smooth, with an apical hyaline pore, shape in face
view narrowly elliptic to nearly oblong, in profile suboblong to obscurely inequilateral, wall about 0.4 f thick.
Basidia 4-spored, 20-24x 9-10 I, clavate, hyaline in KOH. Brachybasidioles
not present. Pleurocystidia none. Cheilocystidia abundant, (32-)40-58 x 10-18 a,
broadly fusoid-ventricose with broadly rounded apex varying to cylindric, wall
thin, smooth, hyaline in KOH, content not distinctive in KOH or Melzer's.
Caulocystidia not studied.
Pileus with a cuticle of vesiculose hyaline cells several cells deep, many
filamentose hyphae 4-7 wide arising from this layer. Hyphae of the trama
loosely interwoven and hyaline in KOH.
Type locality. Manitoba, Canada.
Habit and habitat. Solitary to cespitose on floor of an old "dug-out."
Distribution. Known only from the type locality. Type studied.
Observations. The description of this species is very suggestive of an Agrocybe,
and this point should be carefully checked if fresh material is ever available again.
The "purplish" mottled gills are against the above suggested disposition, but as
is well known, A. dura is often mistaken for a Stropharia. The spores are not
those of a Panaeolus, though one is tempted to compare the species with P.
separatus and P. solidipes. I have studied the type, but if pleurocystidia are
present they are very rare and could be easily missed. If pleurocystidia were
found, and were of the Agrocybe type, that genus would seem to be indicated.
58. Psathyrella huronensis A. H. Smith, sp. nov.
Pileus 4-8 cm latus, conicus, late conicus vel campanulatus, glaber ad marginem appendiculatus, pallidae demum albidae; lamellae albidae demum fuscobrunneae, angustae; stipes 9-14 cm longus, 6-10 mm crassus, cavus, pallidus
sursum furfuraceus, deorsum tenuiter fibrillosus; sporae 8-11 x 5-6 p teres; fibulae
adsunt. Typus. N. J. Smith 1733 (MICH); legit prope Ives Lake, Huron Mountains, Michigan.
Illust. P1. 30; Text Figs. 149-151.
Pileus 4-8 cm broad, conic, expanding to campanulate and often splitting at
maturity, glabrous but margin appendiculate with membranous patches of a veil
which soon disappears, veil material pallid ("tilleul buff"), surface "tilleul buff"
when young and moist, hygrophanous and fading to a dead white, becoming
grayish to avellaneous over the marginal area as spores mature. Context fragile
but rigid, thin, odor and taste not distinctive.
Lamellae white to pallid becoming chocolate-brown, crowded, narrow, ascending, in age the color violaceous-brown ("benzo brown"), edges even.
Stipe 9-14 cm long, 6-10 mm thick, hollow, fragile, equal, whitish over all
and unchanging (at times dusted with spores), pruinose-scurfy above, lower portion with scattered patches of pallid veil material but no annulus present on any
of the basidiocarps observed.
Spores 8-11 x 5-6 /, smooth in outline but in KOH the wall ornamented by
dark punctations (as in Tylopilus gracilis), apex truncate from a typical germ
pore, shape in face view broadly ovate to elliptic, but some obscurely angular,
in profile obscurely inequilateral to elliptic, color in KOH near "mummy brown"
(blackish brown), in Melzer's reddish tawny and appearing perfectly smooth, wall
0.3-0.4 A thick.