The North American species of Psathyrella.

1972]

PSATHYRELLA

31

4. Pileus glabrous or with superficial fibrils that are white, grayish or yellowish
but are soon evanescent. 5
5. Veil granulose (from disarticulation of cells of the veil hyphae). Cystopsathyra.
5. Veil hyphae not as above. 6
6. Stipe typically furnished with a membranous to floccose annulus.
Pseudostropharia.
6. Annulus typically lacking. 7
7. Pleurocystidia absent and pileus margin at first appendiculate from adhering patches
of the inner veil or a combination of both veils (but see subsect. Flocculosae of
subg. Pannucia also). Candolleana.
7. Not as above; a copious outer veil may be present and if the margin is appendiculate
pleurocystidia are present. 8
8. Pleurocystidia with wall in neck or ventricose part 0.5 /, thick or more, or
the apex of the cystidium (especially cheilocystidia) with crystalline or
coarsely granulose incrusting material on at least some of them (as
revived in KOH). Homophron.
8. Pleurocystidia (if present) with walls up to 0.5 JL thick at times but apex
smooth or with only slight finely granular incrustations or coagulated
material (as revived in KOH). 9
9. Cheilocystidia lecythiform (Fig. 862, 863); veil absent. Conocybella.
9. Cheilocystidia various but not as above. 10
10. Veil thin to rudimentary or absent (check button stages). Psathyrella.
10. Outer veil and/or partial veil more or less well-developed; pileus margin
appendiculate with remains of partial veil or a combination of both.
Pannucia.
Psathyrella subg. Panaeolina (Maire) A. H. Smith, comb. and stat. nov.
Panaeolina R. Maire, Trebl. Mus. Cien. Nat. Barcelona 15: 109. 1933.
In a broad concept of Psathyrella, P. foenisecii, in my estimation, is better
placed here than anywhere else. It has already been noted that not all species
of Lacrymaria have ornamented spores, and that P. neotropica which also has
ornamented spores, is not closely related to Lacrymaria. Furthermore, species
of the latter subgenus have gills mottled much as in Panaeolus, so this feature
cannot be considered as restricted to the latter. The spores in Psathyrella have
been found to be rather diverse in their reactions to chemicals: they may be
hyaline or nearly so in KOH or reddish to cocoa-color, or chocolate-black to
black, and in at least one species become strongly violet on standing in the
medium, reminding one of the color change when spores of most species are
mounted in sulphuric acid. In Melzer's they vary from pale yellowish tan to
dark bay-brown. To me the indication for the genus is that the spore pigments
are quite diverse and vary from stable to unstable, and this certainly vitiates
using a single chemical change in a single species such as the sulphuric acid
reaction, as a generic character for a genus of two species. I find the disposition of
the species made by Quelet (1886), and Bertrand (1901) much more logical and
is the one I have adopted here. All three of us have used different generic names
to distinguish the same concept.
The relationships of this subgenus appear to me to be with species of subsection Psathyrella.
Type. Psathyrella foenisecii.
Key to Species of Subgenus Panaeolina
1. Stipe 1-3 mm thick; odor and taste typically not distinctive. 1. P. foenisecii.
1. Stipe 3-6 mm thick; odor and taste typically noticeable (odor strong, taste
unpleasant). 2. P. castaneifolia.