The North American species of Psathyrella.

1972]

PSATHYRELLA

159

Spores 7-9 x 4-5 v, smooth, apical pore distinct, apex with a small truncation,
shape in face view elliptic to ovate, in profile subelliptic to obscurely inequilateral,
color in KOH soon becoming a pale tawny above, nearer clay-color when first
revived, in Melzer's tawny, wall about 0.5 Pu thick.
Basidia 4-spored, 7-9 v wide, hyaline in KOH. Pleurocystidia 38-50 x 9-14,u,
fusoid-ventricose, the neck 4-6 /u wide and apex obtuse to subacute, some with
granular material over and around the apex, wall thin and hyaline, cell content
not distinctive. Cheilocystidia similar to pleurocystidia or smaller, also clavate
to vesiculose cells are also present in varying numbers. Pileus cuticle of inflated
cells with brownish to ochraceous walls in KOH, cell content not distinctive.
Hyphae of the subcutis with some incrusted pigment on them (the area pale tawny
in KOH). Clamp connections present.
Type locality. Clingman's Dome, Great Smoky Mountains National Park,
Tennessee.
Habit and habitat. Subcespitose on a spruce log.
Distribution. Known only from the type locality.
Observations. Psathyrella rugulosa is closely related to P. septentrionalis but
occurs on conifer wood, and the cystidia are narrower at the apex. There are other
features also, such as the color of the spores in KOH, which indicate that the two
are different.
115. Psathyrella pseudoparadoxa V. Wells & A. H. Smith, sp. nov.
Pileus 2.5-4(-6) cm latus, convexus demum campanulatus vel late convexus,
cinnamomeo-brunneus, sparse fibrillosus, glabrescens, ad marginem appendiculatus, demum rugulosus; lamellae pallidae demum fusco-brunneae, latae
(5-9 mm), confertae, ad marginem interdum lacto-guttatae; stipes 5-9 cm longus,
3-5 mm crassus, pallide alutaceus, deorsum floccosus, glabrescens; sporae 7-9X
4-4.5 /u; pleurocystidia 42-70x9-17 /, fusoide ventricosa, acuta vel obtusa;
fibulae adsunt. Typus. Wells-Kempton 8/27/64 no. 1 (MICH); legit prope
Girdwood, Alaska.
Pileus 2.5-4(-6.0) cm broad, convex to ovate, the margin connivent to the
stipe, becoming campanulate to broadly convex with an obtuse umbo, hygrophanous, when moist cinnamon-brown, fading to pale buff, buttons typically covered
with white radially appressed fibrils breaking (aggregating) into squamules,
margin appendiculate, glabrescent and surface often rather strongly radially
rugulose. Context concolorous with the surface, very thin, brittle, odor and taste
not distinctive; FeSO4 negative, KOH-negative, ammonia-negative.
Lamellae pallid to white becoming pale tan to grayish and finally purplebrown, dark vinaceous-fuscous as dried, adnate to adnexed, close, moderately
broad (5-7-9 mm), edges pallid, whitish, entire, at times beaded with clear to
milky droplets of moisture.
Stipe 5-9 cm long, 3-5 mm thick above, equal or evenly enlarged below, pallid
to pale tan, dry, silky, polished, smooth to undulating, apex pruinose, becoming
glabrous below, base somewhat floccose-fibrillose. Veil fibrillose to submembranous, not leaving a ring on the stipe.
Spore deposit blackish, spores 7-9 x 4-4.5 A, smooth, apical pore distinct but
apex only obscurely truncate, shape in face view narrowly elliptic to ovate, in
profile obscurely inequilateral to subelliptic, color in KOH dark cocoa-color
slowly becoming chocolate-brown, in Melzer's tawny, wall about 0.3,p thick.
Basidia 4-spored, clavate, 18-25x8-9 p. Pleurocystidia abundant, 42-70 x
9-17 v, mostly broadly fusoid-ventricose with subacute to obtuse apex, but some