North American species of Mycena.

362 NORTH AMERICAN SPECIES OF MYCENA

X 8-12 g. Specimen typicum in Herb. Univ. Mich. conservatum.
Legit A. H. Smith, n. 4444, prope Lake Timagami, Ontario, Sept. 2,
1936.
Pileus 5-15 mm. broad, convex to broadly convex, the margin
straight, in age the disc flattened or very shallowly depressed and the
margin somewhat crenate at times, surface moist, hoary pruinose
when young but soon glabrous and polished, subhygrophanous,
faintly striatulate before fading, color deep dull grayish brown fading
to pale cinnamon brown or buff ("bister" on disc, "snuff brown"
toward the margin or evenly colored "bister" at first but fading to
"clay color" or "cinnamon buff," sometimes becoming "cinnamon"
to "pinkish cinnamon" before losing moisture); flesh thin, firm, no
odor or taste, concolorous with pileus; lamellae close to subdistant,
14-19 reach the stipe, one or two tiers of lamellulae, arcuate, becoming decurrent by a long tooth, narrow to moderately broad, whitish or
tinged cinnamon buff, edges even or slightly fimbriate under a lens;
stipe (2) 3-7 cm. long, 1-1.5 mm. thick, tubular, cartilaginous-fragile,
pruinose but soon glabrous and polished, concolorous with the pileus,
base echinulate-strigose with white fibrils.
Spores 5-7 X 5-6 u, subglobose to broadly ellipsoid, smooth,
white in mass, nonamyloid; basidia 24-26 X 6-7 u; pleurocystidia
rare to absent, usually near the gill edge; cheilocystidia abundant to
scattered, 28-46 X 8-192, fusoid-ventricose to narrowly fusoid,
apex occasionally branched; gill trama homogeneous, reddish brown
in iodine (not vinaceous); pileus trama with a thin adnate pellicle,
the hyphae of which give off numerous short filamentous projections
(which cause the pruinose appearance of the cap), beneath this a distinct hypoderm of enlarged cells which intergrade gradually with the
rest of the trama, reddish to reddish brown in iodine.
Habit, habitat, and distribution.-Single or scattered on logs of
cedar (Thuja occidentalis) or other conifers. Early summer and fall.
Apparently not common. The type was collected in Ontario, Canada.
It has also been found in Michigan and California. The California
collection (3672) was from a redwood log.
Material studied.-Smith, 33-438, 33-531, 3672, 4444. Mains,
5064.
Observations.-The structure of the pileus indicates that this
fungus belongs in Mycena. The nonamyloid spores, however, distinguish it from most other members of the Omphaliariae, the gray
species in particular. In its consistency it bears some resemblance to