North American species of Mycena.

EUMYCENA: TYPICAE

355

cespitose, particularly -on logs and debris of maple or aspen but on
wood of other deciduous trees as well, during the summer and fall;
Tennessee, New York, and Michigan in the United States and Nova
Scotia and Ontario in Canada. Hesler and Meyer (13781) found it
on a balsam log at Clingman's Dome in the Great Smoky Mountains
National Park.
Material studied.-Smith, 32-525, 33-689, 226, 478, 485, 499, 747,
786, 869, 952, 995, 1051, 1362, 4587, 6275, 6314, 6383, 9542, 10698,
15097, 15433. Hesler, 14196, 14201, 14204, 14252, and Hesler and
Meyer, 13781. Wehmeyer, 869.
Observations.-The pale colors, tough consistency, subviscid pileus,
glabrous stipe at all stages of development, and usually the presence
of a pseudorhiza, along with the roughened cheilocystidia and broad,
short spores, distinguish it. The pseudorhiza is best developed when
the fruiting bodies arise from a soft substratum. The colors are
always pale grayish to whitish and rather sordid.
An examination of the type has shown that the spores are smooth
and otherwise as described above. The apparent roughness Peck
saw was no doubt caused by numerous very small oil drops arranged
around the periphery just inside the spore wall, a not uncommon
occurrence in hyaline-spored agarics. The type specimen is small,
but it is obviously a carpophore of a species in the series containing
M. galericulata. M. subviscida was described as a new species from
Michigan. Up to that time neither Kauffman nor I had examined
the type of M. radicatella, and we did not suspect its identity with
M. subviscida. Murrill apparently did not examine the spores of the
type, since he copied Peck's error in his account in the North American
Flora. M. adirondackensis Murrill is a luxuriant form of M. radicatella. The pellicle of the specimens in the type of Peck's species is
well developed. Consequently it is very likely that the species was
subviscid when fresh. Murrill described the pileus of M. adirondackensis as sulcate, but this character probably developed as a result
of aging or of being exposed to the weather for some time before the
fruiting bodies were collected. The iodine reactions of all parts are
similar in the types of all three species and are very pronounced.
In the field I have been able to recognize only one species with these
characters. In the absence of significant differences it is necessary
to reduce M. subviscida and M. adirondackensis to synonymy with
M. radicatella. Smith and Wehmeyer (1936) reported this species
under the name M. atroumbonata.