North American species of Mycena.

TECHNIQUE AND MATERIAL
EXAMINED
FIELD WORK
T HE field work which forms the basis of this monograph was
carried out largely in two areas, one extending across the continent from Nova Scotia to the Olympic Peninsula of Washington,
and the other reaching in a north-south direction from Lake Timagami in Ontario to the Great Smoky Mountains of Tennessee and
North Carolina. Obviously such coverage is by no means complete
for the entire area of the United States and Canada, and many forest
types still remain almost completely unexplored. However, the
regions in which field work was conducted were those in which, to
judge from the studies of previous investigators, it was evident that
an abundant Mycena flora occurred, and the places neglected are
largely the ones in which species of Mycena form only a very minor
part of the known agaric flora. Because of the difficulties encountered
in collecting agarics it should not be assumed that the neglected areas
will not, under favorable conditions, produce an interesting Mycena
flora of considerable diversity. This applies particularly to regions
adjacent to the Gulf of Mexico. Since species of Mycena appear to
be more numerous in cool climates, and are very abundant under
conifers, a great deal of the collecting was carried on in the mountains,
particularly in the northern United States, and in sphagnum bogs in
Michigan and the Pacific Northwest.
As many different forest types as possible were investigated in the
regions surveyed. In the vicinity of Ann Arbor, for instance, local
conifer plantations were studied intensively, and a systematic effort
was made to investigate the various forest types of the Central
Hardwood Region. The same procedure was applied to the forest
types in northern Michigan although the studies were not so extensive
as in the vicinity of Ann Arbor. The other regions which were intensively studied are northwestern Washington, the Cascade Mountains in central Oregon, and northern California. One period of good
collecting was experienced in the mountains of central Idaho and
another in Nova Scotia. Collecting in New York State and in the
Lake Timagami district of Ontario was somewhat unsuccessful be31