North American species of Mycena.

PSEUDOMYCENA: BASIPEDES

The spore size is also variable. In deposits from a number of
collections they measure 6-8 X 3-4,u, 7-9 X 3.5-4 u, 6-8 X 3.5-4 1u,
8-10 X 4-4.5 t,, 8-10 X 3 u, and 6-7.5 X 3.5 u. In one form with
two-spored basidia the spores measured 11-14 X 2.5-3 u. Scattered
four-spored basidia on the same sections had spores 8-10 X 3-5.5 /.
Between some species the difference of 6-8 and 8-10 u in spore length
is significant, but I cannot so regard it here. Ktihner gives the length
of the spores as 7-10, long, and illustrates the cheilocystidia as decidedly variable in shape, as in American collections.
A form with a strongly plicate pileus was found on mossy alder
logs in the Hoh River Valley of Washington (A. H. Smith, 13589,
14111). The flesh was soft and, in general, the fruiting bodies had
the aspect of a Pseudocoprinus. Two collections were made from the
same log within a month. In view of the spores (8-10 X 4-5 1),
the cheilocystidia (intermediate between the fusoid-ventricose and
the clavate-roughened types), and the gelatinous pellicle, I am placing
the collections here. More observations are needed to determine
just how constant the striations and the soft consistency are before
giving them further consideration. They could very easily be chance
variations. Typical M. stylobates was also found in the same vicinity
on debris under willows in the river's flood plain. M. coprinoides
Karsten (1883) appears to be somewhat similar to collections 13589
and 14111, but differs in the color of the pileus. Karsten recognized
the relationship of M. coprinoides to M. stylobates.
6. MYCENA BULBOSA (Cejp) Kiihner
Encyc. Myc., 10: 176. 1938
Pseudomycena bulbosa Cejp, Publ. Fac. Sci. Univ. Charles, 104: 149. 1930.
(The following description is adapted from Kuhner.)
Pileus 3.5-6 mm. broad, hemispheric or convex, 2.5-5 mm. across
the base, obtuse or submammillate, radially striate and somewhat
plicate (the creases not over the backs of the large lamellae), grayish
brown, paler with age but the striae always strikingly colored, hygrophanous, fading from the center, glabrous and not spinose as in
M. stylobates, with an entirely gelatinous separable pellicle; flesh
thin, odor and taste mild; lamellae 9-12 reach the stipe, one to three
tiers of lamellulae, whitish or with a hyaline-grayish tint, ventricose,
nearly free, separating from the stipe in a star-shaped arrangement,
slightly intervenose; stipe 4-10 mm. long, 0.2-0.5 mm. thick, sub