The North American species of Psathyrella.

1972]

PSATHYRELLA

353

Distribution. Michigan.
Observations. The spores are distinctly narrower than in P. spadiceogrisea
to which it is closely related. In Hesler 19454 the spores are 7-9(-10) x 4-4.5 /A
and the pleurocystidia develop apical to subapical protrusions. It deserves further
study.
Material examined. Michigan: Potter 4439, 4490; Smith 18950 (Type), 18953,
20296,25141, 25349, 25653, 32290, 32361.
325. Psathyrella distantifolia Murrill, Mycologia 14: 277. 1922.
Illust. Text Fig. 705.
Pileus about 3 cm broad, convex to expanded, becoming slightly depressed at
the center at times, surface dry or slightly hygrophanous, glabrous, conspicuously
striate, dark isabelline to fuliginous.
Lamellae adnate or sinuate, broad, distant (not distant on type as dried),
becoming dark fumosus to almost ater (black) whitish on the edges.
Stipe 7 cm long, 2-3 mm thick, slender, equal, smooth, white, glabrous, hollow.
Spores 7-9(-10) x4.5-5(-5.5) Ju, smooth, apex truncate by a broad apical
hyaline pore, shape in face view ovate to nearly elliptic, in profile subovate to
obscurely inequilateral, dark date brown as revived in KOH, in Melzer's dull
tawny-red to bay, wall 0.5-0.6 p. thick.
Basidia 4-spored, hyaline, reviving poorly. Pleurocystidia scattered, 32-52 x
9-13 A, fusoid-ventricose with short thick necks and rounded to obtuse apex, wall
thin, smooth and hyaline, cell content not distinctive. Cheilocystidia (not reviving well in the type). Caulocystidia present as occasional clavate cells.
Pileus cuticle a layer of vesiculose cells 1-2 deep, the wall thin and hyaline,
cell content not distinctive. Hyphae of the subcutis not highly colored in KOH
(but basidiocarp was old). Clamps present.
Type locality. Bronx Park, New York City, New York.
Habit and habitat. Solitary on loam in woods.
Distribution. Known only from the type locality.
Observations. Although this species is recognized here largely because of the
broad distant gills, there is the distinct possibility that it will never be accurately
recognized since in the dried specimen the gills do not appear distant.
326. Psathyrella amarella A. H. Smith, sp. nov.
Pileus 3-5.5 cm latus, late convexus, glaber, cinnamomeo-brunneus; contextu
brunneus; sapor amarus; lamellae confertae demum sublatae, brunneolae demum
fusco-brunneae; stipes 6-8 cm longus, 4-6 mm crassus, albidus, deorsum brunneus,
sparse fibrillosus; velum sparsum; sporae 7-9 x4-5 /p; pleurocystidia 38-60 X
9-18 p utriformia vel fusoide ventricosa, late rotundata vel (rare) subacuta;
fibulae adsunt. Typus. Ammirati 2925 (MICH); legit prope Dynamite Hill,
Baraga County, Michigan.
Illust. Text Figs. 706-708.
Pileus 3-5.5 cm broad, broadly convex expanding to plane or with the margin
becoming uplifted, surface glabrous, moist and hygrophanous, color "cinnamonbrown" fading to dingy tan and drying pallid, striate when moist, veil rudimentary. Context thin, fragile brownish fading to pallid, taste bitter, odor not
distinctive.
Lamellae close, narrow to moderately broad, adnate, brownish at first then