The veiled species of Hebeloma in the western United States / Alexander H. Smith, Vera Stucky Evenson, and Duane H. Mitchel.

APPENDIX
Selected Extralimital
Species
Species come to be known, for example, as "European," "North
American," or "Australian" on the basis of the geographical area from
which they were first described. This same pattern is continued on a
continental basis and we designate as "Canadian" any species described
from Canada, or "Mexican" if described from Mexico. It should be
apparent to those using the present publication that many of our "western" species (for both the United States and Canada) will be found in
the Great Lakes and northeastern regions generally. This was indicated
years ago (Smith, 1947) for species of Mycena. It also means that "eastern" species not yet found in the western area will eventually be found
there. This is brought about by comparable habitats and identical genera of host trees for mycorrhiza-formers-such as Hebeloma.
Consequently we considered it desirable to add a category of
extralimital species to include most of those brought to light by the
present study. Our presentation here is not to be regarded as complete
for the areas indicated.
Kauffman (1918) in section "Indusiati" (the veiled species), included H. velatum Pk., H. fastibile Fr., H. mesophaeum Fr., H. gregarium, and H. pascuense.
The fact that by present count 20 taxa for the general area, as
covered by Kauffman, are recognized is significant and indicates that
the diversity found in the western flora will be comparable to that in
our eastern and southern areas when these have been adequately
studied. The treatment by Murrill (1917) and Peck's contributions over
the years come nearest to showing an appreciation of the diversity in
this subgenus of Hebeloma for North America.
In the present contribution the extralimital species are included
in the main keys but are designated by a letter within parentheses:
"Hebeloma sterlingii (o)" for example. In the appendix the species are
arranged in alphabetical order and are numbered consecutively.
Extralimital Species
H. affine (a)............................................... 94
agglutinatum (b)........................................ 95

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