North American species of Mycena.

118 NORTH AMERICAN SPECIES OF MYCENA

its hyphae giving rise to various types of more or less upright protuberances or even to cells which give the surface its unpolished
appearance; beneath the pellicle is a layer of enlarged cells filled with
a bright-yellow substance, the central portion of the trama is of
floccose hyaline hyphae, the subhymenium containing a few greatly
enlarged cells with or without yellow contents, all parts yellowish in
iodine; stipe tissue yellowish in iodine.
Habit, habitat, and distribution. Scattered to gregarious on
needles of Douglas fir and spruce; Washington, Oregon, and California. Kauffman reported it on oak leaves and pine needles.
Material studied. Smith, 3018, 3586, 7805, 7810, 7842, 7865,
8025, 8130, 8240, 8625, 8816, 9279, 16751. Flett, 1940, Bremerton,
Washington. Kauffman, Oregon.
Observations. During the season of 1937 this species was collected in quantity in the Cascade Mountains around McKenzie Pass
in Oregon and later in northern California. The protuberances
which develop from the hyphae of the pellicle give the cap an unpolished appearance, but in carpophores in which they are only
scattered over the surface the pilei are almost shiny. Neither the
pileus nor the stipe has ever been found to be even subviscid to the
touch (they feel dry when compressed between one's fingers), and no
incrusting material has been seen, either on the caulocystidia or on
the protuberances from the pellicle, which might lead one to describe
these organs as glandular. The pleurocystidia are best demonstrated
in fresh material. Their bright-yellow content makes them readily
visible. As the fruiting body ages, the yellow fades, and in old caps
the pleurocystidia are difficult to find. The cheilocystidia are very
abundant and cause the gill edge to be margined with bright yellow.
The color of the margin fades as the yellow content of its cystidia
fades, and in old pilei the margins may be concolorous with the gill
faces.
Mycena siskiyouensis was based on Kauffman's description (1930)
of M. aurantiidisca Murrill. At the time I described both M. oregonensis and M. siskiyouensis the differences evident between my
collections from Washington and Oregon and Kauffman's description
appeared to be too great to be disregarded. In the light of the 1937
collections, however, the discrepancy in regard to the presence of
pleurocystidia in one and their absence in the other is readily explained, as is also the reported difference in the color of the gills.
Kauffman's description of glandular hairs over the pileus and stipe