North American species of Mycena.

EUMYCENA: TYPICAE

formed hypoderm not sharply separated from the remainder of the
filamentous trama, all but the pellicle staining brownish in iodine.
Habit, habitat, and distribution.-Gregarious to cespitose on
stumps, logs, and debris of alder, Douglas fir, and rhododendron;
Washington, Oregon, and California. It was common during the
fall of 1935 but very rare during the season of 1937. In the spring of
1939 it was found sparingly in Washington. Kauffman (1926) reported it as common around Mt. Hood in October.
Material studied.-Smith, 2575, 2744, 3003, 3124, 3361, 3474,
3607, 3684, 3838, 8021, 8621, 13690, 16312, 16384, 16523, 16794.
Gruber, Oregon. Kauffman, Oregon.
Observations.-Kauffman described the pileus as hygrophanous
and "cinnamon drab" to "avellaneous," with the umbo "Sayal
brown." These were the colors of fading pilei in my collections.
Even in continuous wet weather the colors usually fade as the fruiting
body matures. The pileus and the lower part of the stipe are frequently about the same color-as Kauffman described them. In
young specimens these parts are usually blackish. The pinkish tints
of the gills are most frequently present in the forms with avellaneous
pilei, and the habitat is not necessarily limited to wood and debris of
conifers.
Kauffman commented on the trama of the pileus as follows:
"The surface layer of the pileus is corticate, composed of one or two
series of globose pyriform, brown cells." I have examined the type
and found the cap trama to be made up of a thin pellicle of very
narrow hyphae beneath which is a region of inflated hyphae (the
hypoderm), the cells of which may appear pseudoparenchymatous
if a good tangential section is obtained. This is the layer Kauffman
referred to, although, from his comment, one might easily suppose
that he was describing the type of cuticle found in M. rorida or in
species of Conocybe. In iodine the trama of the cap and the gills
of the type become vinaceous brown and the spores bluish. Kauffman illustrated the long-stiped form. That on Plate 84 is of the
form collected around stumps in open places.
The lack of farinaceous taste and the presence of sordid-reddish
stains on the gills appear to distinguish the species from robust forms
of M. galericulata. The two are very closely related, however, and
may not be distinct. Kihner (1938, p. 329) has discussed the relationship of M. rugosa to M. galericulata and, with Lange, is inclined
to regard the former as merely a large M. galericulata with ashy rather