North American species of Mycena.

EUMYCENA: FLOCCIPES

383

when moist, color "fuscous" on the disc at first and "buffy brown"
toward the margin, becoming paler and often watery gray before
fading, hygrophanous, fading to "olive buff" or whitish; flesh thin,
pliant, watery gray, odor and taste mild; lamellae adnate or subdecurrent, at times readily seceding, crowded, 18-25 reach the stipe,
lamellulae in three or four tiers, narrow, white, edges even and pallid,
sometimes crisped or wavy; stipe 2-3 cm. long, 1-1.5 mm. thick,
equal, solid, brittle, white-strigose around the base, densely pruinose
to subpubescent over all, whitish above, pallid to grayish or sordid
yellowish near the base in age.
Spores globose to subglobose, 3.5-4 A, smooth, hyaline, nonamyloid; basidia four-spored, 20-22 X 5-6 A; cheilocystidia hyaline,
subcylindric to subventricose with obtuse apices, 40-50 (60) X 9-192 u,
numerous; pleurocystidia present only near the gill edge and similar
to the cheilocystidia; caulocystidia very numerous, 40-50 X 8-10,,
filamentous with obtuse apices; gill trama yellowish in iodine; pileus
trama without a differentiated pellicle, the surface region composed
of a compact mass of radially arranged hyphae which are one or two
times the diameter of the hyphae forming the remainder of the tramal
body, in tangential section the surface region appearing cellular owing
to the cut ends of the hyphae which form it, both stipe and pileus
trama yellowish to yellowish brown in iodine.
Habit, habitat, and distribution.-Gregarious on elm logs which
have not lost their bark and are still solid. It usually fruits in June
and, apparently, does not favor logs which are more or less covered
with moss. Hesler found it in August at Highlands, North Carolina.
Material studied.-Smith, 6284, 6303, 9645. Hesler, 14688.
Observations.-This species reminds one to a certain extent of
M. marginella var. rugosodisca, but it lacks a copious watery juice,
grows on a different kind of wood, and has different spores. Because
of the absence of a pellicle over the pileus one might consider the cap
to be corticated, and hence try to place the species in the following
section. Its natural affinities, however, are with M. floccipes. It
has a superficial resemblance to M. fuliginella, but is never so dark;
its spores are nonamyloid, and they differ decidedly in size and shape.
Kiihner groups these species in the subgenus Paramycena and includes, along with M. floccipes and M. Kauffmanii, M. subalpina
von Hihnel, which has spores somewhat similar to those of M. fuliginella but nonamyloid. He considers M. pseudoradicata Lange
and M0ller to be synonymous with von Hohnel's species.