North American species of Mycena.

EUMYCENA: TYPICAE

245

Observations.-The fragile, conspicuously striate dark-gray pileus,
pale fragile stipe, and tendency to stain reddish brown when bruised
or in age characterize it among the gray Mycenae. The dark-ashy
to blackish-gray evenly colored faded pilei are also distinctive. Most
species become appreciably lighter in color as moisture escapes.
This species differs from M. stannea by its conspicuous broad
blackish striations, which extend to the disc, by the tendency of all
parts to stain reddish brown, and by its more watery-fragile consistency, as well as by its lack of pleurocystidia. It appears to be
very close to M. strobilicola Favre et Kiihner but lacks the distinctive
odor of M. strobilicola and has no pleurocystidia. I~ihner has commented on some interesting observations which Vandendries made
upon cultures of M. strobilicola. In single-spore cultures there is
apparently a segregation of two types of mycelium; one type remains
white and the other soon turns reddish brown in the older parts.
Thus it would not be surprising to find two strains of the species in
nature, one producing fruiting bodies which soon stain reddish brown
and the other producing carpophores that do not stain.
113. MYCENA STANNEA (Fr.) Quelet
Champ. Jura et Vosges, p. 242. 1872
Agaricus stanneus Fries, Epicr. Syst. Myc., p. 111. 1836.
Prunulus murinus Murrill, North Am. Flora, 9: 331. 1916.
Mycena murina Murrill, Mycologia, 8: 221. 1916.
Mycena dealbata Velenovsky, Ceske Houby, p. 327. 1920.
Illustrations:
Plates 42, 43; Text fig. 28, nos. 4, 6 (p. 242).
Bresadola, Icon. Mycol., 5, pl. 244 (as M. aetites).
Fries, Icon. Sel. Hymen., 1, pl. 81, fig. 5.
Smith, Am. Journ. Bot., 22, pl. 4, fig. 1 (as M. murina).
Smith, Mycologia, 27, fig. 2 a (as M. aetites).
Pileus 1-3 (4) cm. broad, obtusely conic at first, becoming broadly
conic, conic-campanulate, convex-umbonate, or nearly plane and
with an obtuse or sharply conic umbo, the margin appressed at first,
often recurved in age, surface even and pruinose when young, soon
naked and sometimes cracking radially, glabrous, translucent-striate
when moist or remaining opaque, colors variable, blackish to dark
gray except for the whitish margin when young (sometimes the entire
pileus evenly colored dull gray), becoming paler in age, usually some
shade of watery gray over the disc and striations, hygrophanous and