The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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observed. Cheilocystidia subcylindric to ventricose, the apex broadly rounded,
28-36x10-14 J/, hyaline in KOH, thin-walled and smooth, cell content not
distinctive in KOH or Melzer's.
Gill trama not reviving well in the type. Pileus having a cuticle of vesiculose
cells more or less one cell deep, the cells with thin, yellowish to hyaline walls in
KOH. Hyphae of the context not distinctively colored in KOH. Clamp connections present.
Type locality. Santiago de las Vegas, Cuba.
Habit and habitat. Gregarious on damp ground underneath buildings.
Distribution. Cuba.
Observations. The dried basidiocarps strongly resemble those of P. hymenocephala in a number of respects, but the red-brown to chocolate-color of the pileus,
and the well-developed outer veil amply distinguish it as a species. The spores
when mounted in Melzer's may appear minutely echinulate, but this was not
visible in KOH mounts. The apparent ornamentation in Melzer's mounts under
high magnifications appeared to be formed by minute particles adhering to the
surface of the spore.
139. Psathyrella canoceps (Kauffman) A. H. Smith, Contr. Univ. Mich. Herb.
5: 43. 1941.
Hypholoma canoceps Kauffman, Pap. Mich. Acad. Sci. 5: 132. 1926.
Illust. Smith, 1. c., pl. 26, figs. 3, 4. P1. 54, fig. b; Text Figs. 311, 312.
Pileus 1-3.5 cm broad, 1-2 cm high, obtusely conic with an appressed margin
when young, becoming campanulate or remaining broadly conic, surface at first
appressed white-fibrillose-silky and the margin fringed, the fibrils more or less
innate but becoming arranged in fascicles and eventually more or less disappearing (but never evanescent as in P. bifrons), color whitish at first from the fibrils,
ground color "cinnamon-drab" to "wood brown" or "avellaneous" (grayish brown
tinged cinnamon), hygrophanous and fading to pallid ("tilleul buff"). Context
thin and fragile, avellaneous fading to pallid, odor and taste none or faintly
radish-like but hardly distinctive.
Lamellae ascending-adnate, close, 24-26 reach the stipe, narrow (2.5-3 mm),
equal, pallid to white but becoming "wood brown" (dark avellaneous), edges even
or becoming white floccose.
Stipe 4-6 cm long, 1.5-3 mm thick, equal, white, fragile, sometimes transversely undulate, hollow, lower portion at first silky-floccose but finally glabrescent, apex fibrillose-pruinose, white or whitish.
Spores (7-) 8-10x4.5-6 p, smooth, apical hyaline pore distinct and apex
typically obscurely truncate, shape in face view ovate to elliptic, in profile mostly
obscurely inequilateral varying to more distinctly inequilateral, color in KOH
dark cocoa-color becoming dark chocolate-color, in Melzer's bay-brown to slightly
paler, wall about 0.4 /t thick.
Basidia 4-spored, 18-25(-37) x8-10 I, clavate, hyaline in KOH. Pleurocystidia none. Cheilocystidia abundant, hyaline, thin-walled, fusoid-ventricose
with apex obtuse to subacute, 40-54x 8-13 /, neck often elongated in age, wall
thin, smooth and hyaline, cell content not distinctive in KOH or Melzer's. Caulocystidia present only as subcylindric to clavate cells of various sizes and rather
scattered in occurrence, the walls thin, smooth and hyaline.
Gill trama regular, the hyphae having inflated cells, pale dingy brown revived
in KOH to hyaline, hyaline in water mounts of fresh material. Pileus having a