North American species of Mycena.

244 NORTH AMERICAN SPECIES OF MYCENA

gray Mycena of fragile consistency. Its alkaline odor, medium size,
typically fusoid cystidia, which are rarely abundant on the faces of the
gills, and the terrestrial habitat are its chief distinguishing characters.
I have never seen the pileus or gills stain brown. The presence of the
alkaline odor is about the only character which sharply distinguishes
it from M. stannea. Numerous variations of M. leptocephala are
found, the more slender of which have been referred by many workers
to M. ammoniaca.
112. MYCENA SUBVITREA A. H. Smith
Mycologia, 31: 281. 1939
Illustrations:
Plate 41; Text fig. 28, nos. 3, 5 (p. 242).
Smith, Mycologia, 31, fig. 1 H (spores).
Pileus 1-3 cm. broad, obtusely conic, or becoming campanulate,
the disc somewhat flattened at times, margin appressed against the
stipe when young and flaring somewhat in age, surface moist, conspicuously translucent-striate to disc, sulcate in age, glabrous, very
hygrophanous, black to "fuscous" on the disc, watery gray toward
the margin, fading to ashy or blackish gray over all; flesh very thin
and fragile, dark watery gray, odor and taste not distinctive; lamellae
bluntly adnate, rather distant, 19-21 reach the stipe, narrow (2.5
mm. =), dark gray and staining reddish brown in age or where
bruised, edges even and pallid; stipe 5-8 cm. long, 1-2 mm. thick,
equal, very fragile and watery, hollow, glabrous, apex frosted, base
scarcely strigose, color pale grayish white, readily staining reddish
brown when bruised or in age.
Spores ovoid, 8-10 (11) X (4.5) 5-6.5 M, amyloid; basidia fourspored, 26-28 X 7-8 t; cheilocystidia inconspicuous, somewhat
fusoid or with an abruptly narrowed neck, smooth, hyaline, 30-38 X
9-12 /z.; pleurocystidia not differentiated; gill trama vinaceous brown
in iodine; pileus trama with a thin adnate pellicle, beneath which is a
well-differentiated hypoderm with its cells having a brown content,
the remaining tissue of filamentous hyaline hyphae, all but the pellicle
becoming vinaceous brown in iodine.
Habit, habitat, and distribution.-Gregarious in small groups under
Douglas fir in Oregon during October. There were from three or
four to about two dozen fruiting bodies in the groups. It usually
appeared in places where M. tenax was very abundant.
Material studied.-Smith, 7811, 8050, 8160, 18124.