The North American species of Psathyrella.

1972]

PSATHYRELLA

53

Key to the Species of Stirps Lacrymabunda
1. Some pleurocystidia when mounted in Melzer's having a distinctly amyloid
content (use mature pilei). 19. P. lacrymabunda var. lacrymabunda.
1. Not as above [or rarely a few very weakly amyloid (content grayish) in P.
lacrymabunda var. aggregata]. 2
2. Taste disagreeable, odor sweetly fragrant, spores 9-12 X 4.5-5 X 4-4.5 wu.
see 27. P. pseudocotonea.
2. Not as above. 3
3. Spores 7-9 X 4-4.5 ju. 20. P. alboalutacea.
3. Spores smaller. 4
4. Pileus with blackish patches of veil material when mature; pleurocystidia
clavate-mucronate. 21. P. maculata.
4. Not as above. 5
5. Odor fragrant, lamellae vinaceous before clouded from spores; cespitose on soil
under spruce and fir. 22. P. duchesnayensis.
5. Not as above. 6
6. Stipe subvolvate as the veil breaks; growing solitary on humus; stipe about
3 mm thick. 24. P. subvolvata.
6. Stipe elongate and subannulate above as veil breaks; stipe 8-12 mm thick;
cespitose on rotten hardwood. 23. P. insignis.
6. Stipe as above but pileus with cottony patches of innate fibrils which discolor
to some degree by maturity. 19a. P. lacrymabunda var. aggregata.
19. Psathyrella lacrymabunda (Fries) Moser in Gams, Kleine Krypt. Fl. Europa,
204. 1953.
Agaricus lacrymabundus Fries, Syst. Mycol. 1: 287. 1821.
Hypholoma lacrymabundus (Fr.) Quelet, Champ. Jura et Vosges, 144. 1872.
var. lacrymabunda
Illust. P1. 10; Text Figs. 65-67, 71.
Pileus (3-)4-8(-10) cm broad, obtuse to convex, becoming campanulate and
finally plane or nearly so, surface more or less covered with fascicles of innate
fibrils, or fibrils grouped to form appressed imbricate scales, scales grayish brown
("wood brown") and more numerous near the margin, disc glabrous at times,
ground color whitish to pale yellowish or finally sordid ochraceous, subhygrophanous but scarcely changing color when losing moisture. Context rather thick,
white, odor and taste fungoid.
Lamellae close to crowded, narrow, adnate-seceding, white at first, finally dark
purplish brown ("Quaker drab"), edges white and floccose and in humid weather
sometimes beaded with droplets of moisture.
Stipe 6-8 (-12) cm long, (6-) 10-15 mm thick, equal or nearly so, hollow, white
throughout, surface at first peronate up to the evanescent annular zone by the
remains of the fibrillose veil, zone sometimes basal and surface above white and
glabrous, or the sheath breaking up into scales or patches over the lower portion
and finally vanishing, silky near the apex, becoming sordid in age and sometimes
stained yellowish, mycelium pale yellow.
Spores 6-7.5 x 3.2-4 /, smooth, elliptic to slightly bean-shaped in profile view,
in face view oblong to narrowly elliptic, the apex with a minute hyaline spot as a
pore and the base often more or less truncate, in KOH soon pale to medium
chocolate-color becoming dark chocolate-color finally, in Melzer's pale to medium
reddish tan, wall about 0.2 I/ thick.
Basidia 4-spored, 20-29 x 7-8 /p, hyaline in KOH, subclavate. Pleurocystidia
abundant, 32-46 x 10-14 (-16) /[, fusoid-ventricose to utriform, thin-walled,