North American species of Mycena.

302 NORTH AMERICAN SPECIES OF MYCENA

with a prominent obtuse umbo in age, margin appressed against the
stipe at first and becoming plane or reflexed in age, sometimes crenate,
frequently splitting radially, surface glabrous, lubricous to subviscid,
very finely radially wrinkled, translucent-striate when moist, somewhat sulcate in age, pellicle separable only in shreds, colors gray with
a tint of cinnamon or the margin nearly white ("cinnamon drab" to
"fuscous" on the umbo), subhygrophanous, fading to pale gray in
age; flesh thick on the disc, whitish to grayish, fragile, no odor, taste
slightly farinaceous; lamellae adnate with a slight tooth, subdistant
to distant, 18-22 reach the stipe, broad (3.5-5 mm.), intervenose,
white, pruinose from cystidia, not staining reddish, edges even and
pallid but pruinose under a lens; stipe 3-5 cm. long, 2-4 mm. thick,
cartilaginous, equal, hollow, often compressed, beautifully whitefibrous when young, glabrescent and rather transparent in age, base
white-strigose, concolorous with or paler than the pileus.
Spores ellipsoid to subovoid (8) 9-10 X (4) 5-6 u, amyloid;
basidia four-spored, 32-34 X 7-8 A; cheilocystidia and pleurocystidia
similar, or the former merely clavate (50) 60-120 X 8-14 j, often
projecting 50-75 u, smooth and fusoid-ventricose at first, nearly
cylindric in age and the elongated neck becoming studded with
numerous small rodlike projections over the apical region (the projections about 2. long), hyaline; gill trama very faintly vinaceous brown
in iodine; pileus trama with a well-developed subgelatinous pellicle
of narrow hyphae, below it a region of vesiculose cells (the hypoderm),
the remainder homogeneous and of narrower hyphae, very pale
vinaceous brown in iodine except for the pellicle; tissue of the stipe
also very pale vinaceous brown in iodine.
Habit, habitat, and distribution.-Gregarious to subcespitose on
wood of conifers during the summer and fall; Alabama, Tennessee,
New York, and Michigan in the United States and Nova Scotia,
New Brunswick, and Ontario in Canada. Very abundant at times.
Hesler has found that it is particularly common near the summit of
Mt. Le Conte in the Great Smoky Mountains National Park.
Material studied.-Smith, 456, 481, 520, 1120, 4474, 7353, 9731,
10856. Atkinson, 13772, 24327. Atkinson, Herb. G. Hay, 123.
Burke, 1942, Alabama. Hesler, 6513, 9059, 10694, 13922, 14255,
June 12, 1938, Indian Gap, Great Smoky Mountains National Park.
Kauffman, September 14, 1944, Lake Placid, New York (as M.
galericulata). Mains, 32-123, 32-474, 5051. Wehmeyer, 759, 759 a-g.
Observations.-During seasons when it fruits sparingly small