North American species of Mycena.

EUMYCENA: ADONIDAE

167

Konrad et Maublanc, Icon. Sel. Fung., 3, pl. 230, I.
Lange, Flora Agar. Dan., 2, pl. 53 G (very good).
Ricken, Die Blatterpilze, 2, pi. 110, fig. 8.
Pileus 1-2 (2.5) cm. broad, obtusely to rather sharply conic when
young, with an appressed margin, becoming obtusely campanulate,
broadly conic or at times nearly convex and then occasionally with
an abrupt papilla on the disc, the disc sometimes flattened, the
margin flaring at maturity or slightly recurved, surface smooth,
glabrous, moist, translucent-striate, hygrophanous, "cream-buff" or
a clearer yellow at first, the margin paler and almost white, fading to
"cartridge buff" on the disc and a dead yellowish white along the
margin, buttons pink in one form; flesh yellowish to white, thick under
the disc, otherwise thin, moderately fragile, odor and taste not distinctive; lamellae ascending and somewhat uncinate or toothed,
narrow at first but becoming rather broad (2.5 mm. and becoming
3-4 mm.), nearly equal or slightly ventricose in age, close to subdistant, 18-24 reach the stipe, two tiers of lamellulae, intervenose at
times, white to creamy white, edges even and whitish, waxy in appearance and consistency; stipe 3-8 cm. long, 1-2.5 mm. thick, equal,
tubular, somewhat elastic, cartilaginous, and not particularly fragile,
base white-strigose or surrounded with a matted white mycelium,
glabrous above the base, pruinose toward the apex, when moist
translucent and slightly transversely undulate or uneven, white to
pale yellow.
Spores 7-9 X 3-4.5 u, ellipsoid, nonamyloid; basidia four-spored;
pleurocystidia and cheilocystidia similar and abundant, fusoid-ventricose with long, rather narrow necks, 46-62 X 9-14 (18),, the neck
often incrusted with a mucilaginous substance, otherwise smooth,
hyaline; gill trama homogeneous, pale yellow in iodine; pileus trama
with a thin, poorly differentiated pellicle, a somewhat differentiated
hypoderm (most pronounced in old caps) and the remainder made up
of somewhat enlarged cells and fairly compact, pale yellow in iodine.
Habit, habitat, and distribution.-Scattered to densely gregarious
on needle beds under conifers and on humus in oak woods during the
fall months; North Carolina, Michigan, Colorado, Wyoming, Idaho,
Washington, and Oregon. The species is rare, but occurs in large
quantities in certain localities.
Material studied.-Smith, 7744, 7840, 8024, 8026, 8035, 11073,
15859, 17012, 17049. Gruber, Oregon. Hesler, 14689. Kauffman,