The North American species of Psathyrella.

1972]

PSATHYRELLA

427

aculeata Quelet apply to the material described. Also, exannulate basidiocarps
of the material described are rather similar to those of P. propinqua.
401. Psathyrella depauperata A. H. Smith, sp. nov.
Pileus 1-3 cm latus, obtuse conicus demum late conicus, pallide fibrillosofloccosus, glabrescens, fulvus, striatus, demum griseobrunneus; fragilis; lamellae
pallidae demum griseobrunneae, confertae, latae, adnatae; stipes 1-3(-5) cm
longus, 2-3.5 mm crassus, fragilis, griseolus demum brunneolus; sporae in cumulo
purpureobrunneae, 7.5-9x4.5-5.5 t/; basidia tetraspora; pleurocystidia 38-52 X
13-18 1A, subutriformia; caulocystidia 50-75x10-18 /, obtusata vel subacuta.
Typus. Smith 80664 (MICH); legit Sharon Hollow, Michigan, 1 Oct., 1971; ad
terram udam.
Pileus 1-3 cm broad, obtusely conic with a straight margin at first, becoming
broadly conic or margin finally recurved, at first with pallid fibrillose flecks near
the margin but soon entirely glabrous, dull tawny when young and moist, striate
and grayish chocolate color when spores have matured; context thin and very
fragile, odor not distinctive.
Lamellae pallid, becoming hair-brown (gray-brown), close, broad, adnate,
thin, edges even, in some caps badly contorted (diseased?).
Stipe 1-3 (-5) cm long, 2-3.5 mm thick, equal, fragile, grayish to pallid,
brownish in age, naked or nearly so at maturity, base slightly strigose and
watersoaked (when fresh).
Spore deposit dark purple brown. Spores 7.5-9x4.5-5.5 A, smooth, with a
hyaline apical spot but mostly not truncate; shape in face view elliptic or nearly
so, in profile slightly bean-shaped to subelliptic, color in KOH soon dark grayish
chocolate-color, tawny red in Melzer's.
Basidia 4-spored, clavate, 9-12 p wide. Basidioles clavate. Pleurocystidia
scattered, 38-52x 13-18 f, subutriform to fusoid-ventricose with rounded apex,
thin-walled, hyaline, content not distinctive in KOH or Melzer's. Cheilocystidia
similar to pleurocystidia or smaller. Caulocystiida in patches, 50-75 X 10-18 /A,
apex obtuse to rounded varying to subacute, fusoid-ventricose, thin-walled, some
bifurcate near apex.
Pileus cuticle a layer 1-2 cells deep as a staggered palisade, the walls thin and
not distinctively colored. Subcutis and adjacent trama strongly vinaceous-brown
(revived in KOH) from incrusting pigments. Clamp connections present.
Habit, habitat and distribution. Scattered on muck in an ash (Fraxinus)
swamp, Sharon Hollow, Washtenaw County, Michigan, October 1, 1971 Smith
80664.
Observations. Some basidiocarps in the area were apparently diseased as was
indicated by the malformed strongly intervenose lamellae. The distinguishing
features of the species are the conspicuous pigment deposits near the cuticle of
the pileus typically dark vinaceous brown soon after mounting dried material in
KOH, the large caulocystidia, habitat, and a veil development intermediate
between that of subgenus Psathyrella and subg. Pannucia.
402. Psathyrella floridana (Murrill) A. H. Smith, comb. nov.
Drosophila floridana Murrill, Mycologia 33: 445. 1941
Pileus 1-1.5 cm broad, hemispheric to broadly convex, not fully expanding,
not umbonate, hygrophanous, smooth, tomentulose, not viscid, uniformly fulvous;