The North American species of Psathyrella.

1972]

PSATHYRELLA

33

of the genus: the cellular cuticle of the pileus, more or less cocoa-colored spores in
KOH, dark purple-brown spore deposit, and typical cheilocystidia.
Material examined. UNITED STATES. California: Morse 5-24-31, 6-12-37;
Smith 8774. Illinois: Shaffer 724, 851. Maryland: Kelly 377, 1024. Massachusetts:
D. H. Linder, R. Singer, et al. 988. Michigan: Baxter 6-23-20; Johnson 1643;
Kauffman 10-15-04; Potter 4514, 4689, 4690, 4740, 4753, 5152, 5253, 5397, 5905;
Smith 6-?-40, 33-1027, 1352, 1371, 1504, 3965, 6328, 6353, 11017, 15568,
23403, 25493. Minnesota: Weaver 6-3-62-Y-2. Montana: Kauffman 7-1-28.
New York: Kauffman 7-13-03; Shaffer 87. Oregon: Gruber, 9-3-45, 5-27-46;
Gruber and Smith 20063. Pennsylvania: Kelly 528. Tennessee: Hesler 13807;
Sharp 12524, 20113. Washington: Cooke 19721; Kauffman 9-29-25, 9-26-25,
10-30-25; Smith 13769. Wisconsin: Shaffer 749. CANADA. Ontario: Grove and
Drayton F7433; Smith 26472. MEXICO. Olguin IPN1491.
2. Psathyrella castaneifolia (Murrill) A. H. Smith, comb. nov.
Psilocybe castaneifolia Murrill, Mycologia, 15: 17. 1923.
Panaeolus castaneifolius (Murrill) Smith, Mycologia 40: 685. 1948.
Panaeolus castaneifolius (Murrill) Ola'h, Le Genre Panaeolus, 149. 1969.
Pileus 2-4 cm broad, convex, not fully expanding, in age often broadly conic,
surface strongly hygrophanous, often rugose, "warm sepia" (dark cinnamon) to
dark fuligineous when moist, pale ochraceous ("pale pinkish buff") and somewhat
zoned when dry, margin even and incurved, translucent striate when moist. Context rather thick and firm, fuligineous moist, pallid faded, with a rather strong
odor and unpleasant taste (or, in Smith's colls. odor and taste mild).
Lamellae adnate to adnexed, broad (6-7 mm), triangular or ventricose, not
crowded, pallid to dark fuscous or castaneus ("Verona brown"), edges whitish.
Stipe 4-6(-9) cm long, 4-6 mm thick, slightly tapered downward, pruinose,
cartilaginous, fistulose, pale ochraceous or ~concolorous with the pileus.
Spores 12-16 x 7-8.5 /, roughened as in P. foenisecii, somewhat truncate from
a hyaline apical pore; ~elliptic in face view, in profile somewhat inequilateral;
color in KOH tawny to russet.
Basidia 4-spored, 24-28 x 10-12 u, hyaline in KOH. Pleurocystidia present as
dark cinnamon-brown basidiole-like bodies 18-24 x 6-10 u imbedded in the hymenium. Cheilocystidia 24-38 x 7-10 /, abundant, fusoid-ventricose to subcylindric,
neck often flexuous and apex typically obtuse, thin-walled, hyaline and smooth.
Gill trama parallel to subparallel, dull cinnamon brown when first revived
in KOH but fading. Pileus cuticle of clavate pear-shaped and vesiculose cells
intermingled and arranged into a somewhat regular palisade. Trama proper of
floccose interwoven hyphae pallid to brownish revived in KOH. Clamps present.
Habit, habitat and distribution. Gregarious along roadsides and in grassy
fields, New York and Washington, and in Quebec in Canada, summer and fall,
rare.
Observations. Ola'h (1969) was in error in supposing that a Latin description was necessary for a species published in 1923. This led him into a series of
nomenclatural errors: for instance, a neotype for Murrill's species is not valid
when there is a holotype in existence.
This species, like its sister species P. foenisecii, is intermediate between
Panaeolus and Psathyrella, and in the broad concept of the latter in this work it
has been placed in accordance with its obvious relationship to P. foenisecii.