The North American species of Psathyrella.

1972]

PSATHYRELLA

83

Spores 7-8x 4-4.5 A, smooth, apical pore distinct, shape in face view elliptic
to ovate, in profile ovate to obscurely inequilateral, color in KOH cocoa-brown
slowly becoming dark chocolate-color, in Melzer's tawny reddish, the wall about
0.3 I, thick.
Basidia 4-spored, 5-7 M wide. Brachybasidioles present, 7-9 J, wide. Pleurocystidia none. Cheilocystidia clavate, cylindric or utriform, apex rounded, wall
thin, smooth and hyaline, content not distinctive. Caulocystidia similar to
cheilocystidia or many of them larger (up to 80 x20 I).
Pileus cuticle a layer of vesiculose cells 1-2 deep, hyaline, smooth, content not
distinctive in KOH or Melzer's. Hyphae of subcutis and trama merely dingy
ochraceous in KOH or in Melzer's, hyphae smooth. Clamps present. No distinctive reactions on any tissue when revived in Melzer's.
Type locality. Ann Arbor, Michigan.
Habit and habitat. Gregarious on garden soil, June.
Distribution. Known only from the type locality.
Observations. The dark rusty brown pileus and stature of Psathyrella
rupchandii are the distinctive field characters. The small spores and lack of
pleurocystidia place it in the P. candolleana group. No setae were located on the
pileus.
Material examined. Michigan: Bailey 6-20-56; Hoseney 1025; Smith 78343
(Type); legit Mr. Rup Chand of Ann Arbor.
44. Psathyrella singeri A. H. Smith, sp. nov.
Pileus 1-2.7 cm latus, campanulatus vel convexus glaber cinnamomeus; lamellae angustae, confertae rufo-brunneae; stipes 5-7 cm longus, 1.3-2 mm crassus,
albus, glaber; sporae 7-7.8x4-4.6 Ik, in "KOH" subhyalinae; cheilocystidia 18 -24x 7-16 A, saccata vel clavata interdum subcylindrica. Typus. Sebring, Florida
(MICH); legit Singer.
Illust. Text Fig. 123.
Pileus 1-2.7 cm broad, campanulate to convex, glabrous, surface moist,
hygrophanous, light reddish brown (near cinnamon-brown when dried), longstriate. Context thin and fragile.
Lamellae adnexed, narrow, crowded, reddish-brownish-argillaceous, edges even.
Stipe 5-7 cm long, 1.3-2 mm thick, equal to very slightly enlarged downward,
white, glabrous, slightly yellowish when dried.
Spores 7-7.8 x 4-4.6 Iu, smooth, hyaline with a faint honey yellow tinge when
revived in KOH, subovate in face view, subelliptic in profile, not or only slightly
flattened, the wall thin and apical pore not distinct.
Basidia 16-18x7-8.5 aj, 4-spored, clavate, hyaline in KOH. Pleurocystidia
none. Cheilocystidia abundant, saccate to subeylindric with very broadly rounded
apex, 18-24 x 7-16 /A, hyaline or very slightly tinged brownish in KOH.
Gill trama of interwoven hyphae bright rusty brown in KOH, subhymenium
not distinctive, pallid in thin sections. Pileus with a cuticle of inflated cells, one
or irregularly 2 cells deep, the walls very pallid brownish in KOH. Hyphae of the
context proper bright rusty brown in KOH beneath the cuticle, paler to nearly
hyaline toward the subhymenium.
Type locality. Sebring, Florida.
Habit and habitat. On sticks in a wooded swamp, August.
Distribution. Florida.
Observations. This species is related to P. hymenocephala but is distinct