North American species of Mycena.

EUMYCENA: TYPICAE

323

Spores broadly ellipsoid, 6-8 X 3-4 t, amyloid (reaction very
strong); basidia four-spored, 23-25 X 5-6 t; cheilocystidia abundant,
short and clavate or becoming subfusoid to cylindric, sometimes
greatly elongated into a narrow lanceolate apex, tips occasionally
forked and occasionally one or two short protuberances may develop
either on the inflated portion or on the neck, 30-40 X 9-12, (clavate
type) or 35-55 X 5-8 A (elongated type), both seen on the gills of a
single pileus; pleurocystidia absent, gill trama faintly vinaceous brown
in iodine; pileus trama with a thin gelatinous surface pellicle, a welldifferentiated hypoderm made up of hyphae having walls that sometimes gelatinize slightly, the remaining tissue filamentous, vinaceous
brown in iodine.
Habit, habitat, and distribution.-Cespitose to subcespitose on
wood of conifers; Tennessee, New York, Michigan, Colorado, Washington, Oregon, and California in the United States and Ontario in
Canada. Overholts found it in Colorado in June at an elevation of
11,000 feet; it was coming up through the snow around old stumps.
Material studied.-Smith, 3919, 4733, 4896, 7024, 8157, 8818,
17621, 18120, 18164, 18187, 18188, 18189, 18190, 18198. Hesler,
11905, 14112, 14775. Kauffman, two collections (as M. collariata),
New York; Takilma, Oregon. Overholts, 1823, 1838.
Observations.-The color changes of this species are curious and
quite distinctive. Fuscous-gray to bluish-gray shades are present
over the disc of the pileus and over the upper part of the stipe in young
carpophores. These fade rather rapidly, and the fungus soon becomes
whitish. In age yellowish tints or discolorations develop. When
dried the pilei are dull whitish over all or some show sordid discolorations. If very young specimens are properly dried, some of the
gray may be retained. The viscidity of the cap is a character of
doubtful value in this species. The pellicle may be thin and hardly
gelatinous or relatively thick and rather gelatinous. Both these
conditions are well shown in my specimens from Oregon and California.,: I have never found the stipe to be truly glutinous, but a
thin peripheral zone of subgelatinous hyphae readily explains the
lubricous to viscid feel. The cheilocystidia are apparently rather
variable also. In old specimens they are usually much elongated.
Considering the variation observed on a single pileus, I am not inclined to attach much weight to slight differences between collections.
A comparison of my collections of 1935, 1936, 1937, and 1941 with
the one made at Rock River, Michigan, and described as M. vulgaris
var. cespitosa by Kauffman and myself, shows that all are identical.