North American species of Mycena.

EUMYCENA: TYPICAE

277

most likely to be confused with M. subplicosa, but it lacks pleurocystidia.
132. MYCENA HUDSONIANA Smith
Contrib. Univ. Mich. Herb., 5: 24. 1941
Illustrations:
Text fig. 33, nos. 3, 6 (p. 275).
Smith, Contrib. Univ. Mich. Herb., 5, pl. 6; pl. 25, figs. 4-5.
Pileus 2-5 cm. broad, obtusely conic, becoming somewhat expanded, usually broadly umbonate, margin appressed against the
stipe when young, glabrous and polished, moist, "fuscous" on the
disc, "drab" toward the whitish margin (blackish on the disc at first,
dark gray toward the margin), hygrophanous and fading to "pale
smoke gray," closely striate when moist, somewhat sulcate in age or
when faded; flesh thin, firm but fragile, concolorous with the surface,
odor mild or faintly fragrant, taste not distinctive or only slightly
subnauseous; lamellae ascending-adnate or with a decurrent tooth
(hooked), close to crowded, 25-30 reach the stipe, narrow (scarcely
2 mm. broad), color "pale smoke gray," edges even and pallid; stipe
3-5 cm. long, 1.5-3 mm. thick, equal, hollow, very fragile, with a faint
hoary bloom at first, soon becoming polished and watery, concolorous
with the pileus or slightly paler above.
Spores 8-11 (12) X 5-6,, amyloid, narrowly ellipsoid or pipshaped; basidia four-spored or occasionally two-spored; cheilocystidia
and pleurocystidia similar and fairly abundant, capitate to abruptly
clavate, the enlarged portion very finely echinulate, hyaline, 32-50
X 15-40 u; gill trama sordid vinaceous brown in iodine; pileus trama
with a thin pellicle, a strongly differentiated hypoderm, and a moderately broad region of floccose tissue, vinaceous brown in iodine.
Habit, habitat, and distribution.-Gregarious on needle beds under
conifers in the Hudsonian life zone, Olympic Mountains, Washington.
The type was collected near Deer Lake, June 24, 1939 (14613). Additional material was found near or below Deer Lake on May 11 (13334)
and June 13 (14301). On May 28 the species was gathered at an
elevation of 4500 feet on the Boulder Lake Trail (13827).
Material studied.-Smith, 13334, 13827, 14301, 14473, 14613.
Observations.-The spore size of M. hudsoniana seems to be somewhat variable. In deposits the spores usually measure 9-12 X 5-6 u,
although in one pileus from the type collection the measurements