The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

[VOL. 24

Psathyrella subg. Lacrymaria (Patouillard) Smith & Singer in Singer, Lilloa 22:
466. 1951. (as Lacrimaria.)
Lacrymaria Patouillard, Hymen. Europ. 122. 1887.
The principle feature of the subgenus concerns the spore ornamentation: the
spores are verrucose, and there is a tendency for the ornamentation to darken
more in KOH than does the wall itself. The clustered pleurocystidia, at least in
part, however, are an equally valid feature as is the aspect of the basidiocarps.
In P. echiniceps we find an exception to the spore ornamentation: in mounts in
KOH the spore appears to be very obscurely ornamented in some collections,
but in Melzer's no ornamentation is evident. In P. neotropica the spores are very
finely punctate-ornamented, but this type is not at all like that characteristic
for Lacrymaria and the other characters of that species do not indicate a relationship to the subgenus.
Type. Psathyrella velutina.
In Europe, P. velutina, P. pyrotricha and P. glareosa are not infrequently
reported. In contrast, we have six species in North America. They may be grouped
on the basis of their relationships into stirpes in the following manner:
Stirps Velutina: Spores verrucose and the apex of the spore with a bubblelike "pore", or apex drawn out into a distinct snout.
Stirps Rigidipes: Spores more or less inequilateral in profile but the apex
not snout-like and ornamentation of the wall less distinct
than in the above.
Stirps Echiniceps: Spores smooth or questionably ornamented, but pleurocystidia in clusters and pigmentation of the basidiocarp
much as in P. velutina.
Key to the Species of Subgenus Lacrymaria
1. Pileus with conspicuous dark brown to blackish hairs or squamules on the surface. 2
1. Pileus glabrous or if hairs or fibrils present, not strikingly different in color than
the ground color of the pileus (may be paler). 3
2. Spores 10-13 X 8-10,i, ornamentation coarse and darker in Melzer's than the
wall proper. 3. P. sepulchralis.
2. Spores 7-9 X 4-5,A (or 8-10 X 5-6.5,), ornamentation weak to apparently
absent. 4. P. echiniceps.
3. Spores 7-9(-10) X 4-5 S. 8. P. subcinnamomea.
3. Spores 9-12 X 5.5-7 tA, distinctively warty under a low power oil immersion lens. 4
4. Pileus glabrous, rugulose, 6-10 cm broad; spores finely but distinctly
verrucose. 6. P. rugocephala.
4. Not with above combination of features (pileus fibrillose at least to some
degree). 5
5. Spores with a distinct broad suprahilar depression as seen in a profile view (see
Fig. 9). 7. P. rigidipes.
5. Spores lacking such a broad suprahilar depression (the latter when present smaller
and more abrupt than in above choice, see Fig. 13).
6. Taste somewhat disagreeable; hyphae composing the fibrils of the pileus
distinctly incrusted with zones or spirals of colored materials as seen
revived in KOH. 5a. P. velutina var. boughtoni.
6. Taste mild, fibrils on pileus punctate-roughened to smooth as seen under
the microscope in KOH. 5. P. velutina var. velutina.