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

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The Veiled Species of Hebeloma

2. Bitter, as in quinine or hops, is occasionally encountered in
Hebeloma.
3. Acrid is often confused with bitter but, as used commonly in
mushroom descriptions, applies to the taste of "hot" peppers
(a sharply burning sensation).
4. Radish (raphanoid) taste and odor is commonly encountered;
when strong the odor becomes unpleasantly pungent. In some
species, especially if not checked when first collected, the odor
is faint and of little value taxonomically. On the other hand,
some dried specimens when revived still have a strong raphanoid taste and odor.
5. Farinaceous is described only when it is a distinct taste and/or
odor. When it is faint or only slightly musty it cannot be
distinguished from bland.
6. Mild or bland as a fungous odor is worth noting, but only as a
negative character.
Discoloration of Stipe and Color of Veil. The darkening of the
stipe from the base upward has been used as a taxonomic character by
students of Hebeloma for years. In some species this seems to be a
fairly reliable trait, but must be observed on fresh material. Without
good field notes, it seems of little value in herbarium studies. The
color change represents a chemical process, the expression of which we
assume to be a genetically controlled feature. We have given this character less emphasis than did Hesler, but as most previous investigators,
we regard it as distinctive within limitations.
The color of the veil is sometimes readily apparent and of taxonomic value. Frequently, however, the scanty, fibrillose veil is noticeable only on very young specimens or can be seen only as patches on
the cap or as scattered fibrils on the stipe and therefore its color is
difficult to determine. Discoloration of the stipe producing a contrast
with the veil color seems to occur with some reliability in a few species.
We have not relied on veil color as a distinctive character in this work
except when combined with other features.
Concerning Phylogeny
Our study of the veiled species of Hebeloma has brought to light
some features that we hope will be observed in more detail as Hebeloma and related genera are studied further. At present we believe
that the genus was derived from Cortinarius. Any beginning mycologist
will attest to the difficulty of distinguishing these two genera in the
field. As we have pointed out, the habitat relationships, seasonal variations in fruiting, and mycorrhizal associations are similar. On this as