The North American species of Psathyrella.

1972]

PSATHYRELLA

103

Subsection Appendiculatae
Key to the Species of Subsection Appendiculatae
1. Spores 12-15 X 6-8 j; pileus with distinct often deep vinaceous to vinaceous-brown
tints. 62. P. barlae.
1. Not as above. 2
2. Spores 12-15 X 5.5-6.5 u; pileus walnut brown (dingy vinaceous-brown).
63. P. hortensis.
2. Not as above. 3
3. Spores 12-15 X 5.5-6.6 X 6.6-8 ju; pileus honey-brown; growing on wood of conifers.
64. P. piceicola.
3. Not as above. 4
4. Pileus prominently conic; densely clustered on alder logs; spores 9-12 X5-6 I,
apex truncate. 65. P. cuspidata.
4. Not as above. 5
5. Spores ochraceous-hyaline in KOH, not flattened. 66. P. neotropica.
5. Spores dark colored in KOH. 6
6. Northern and vernal; stipe bulbous; growing on sticks partly submerged
in cold water. 67. P. submontana.
6. Not as above. 7
7. Spores flattened slightly; pileus chestnut brown. 68. P. castaneicolor.
7. Spores terete; pileus honey to rusty brown in color. 8
8. Brachybasidioles differentiated; pileus honey-brown and very delicate in
texture. 69. P. praetenuis.
8. Brachybasidioles not differentiated. 9
9. Scattered to gregarious on debris. 70. P. semivestita.
9. Cespitose, stipes often connate at base; growing around alder and aspen stumps.
see 488. P. emmetensis.
62. Psathyrella barlae (Bresadola) A. H. Smith, Contr. Univ. Mich. Herb. 5: 39.
1941.
Psathyra barlae Bresadola, Fungi Trid. 1: 84. t. 91. 1887.
f. barlae
Illust. Bresadola, op. cit., t. 91; Smith, op. cit. pis. 16, 30, figs. 3, 4, 6. Pl. 75, fig. a;
Text Figs. 157-159.
Pileus 3-5 cm broad, obtusely conic when young, becoming plane or with a
low broad umbo, surface glabrous on the disc and with a narrow fringe of
whitish fibrils along the margin when young, glabrescent, color "warm blackish
brown" to "dark livid brown" when young (deep vinaceous red), the disc soon
"pale grayish vinaceous" to "russet-vinaceous" (paler vinaceous-red), hygrophanous, striate when moist, disc near "cinnamon-buff" when faded (pale tan),
atomate when faded and becoming somewhat rugulose. Context thin, firm, brittle,
concolorous with the surface when either moist or faded, odor and taste mild.
Lamellae bluntly adnate, soon seceding, close to subdistant, about 3 tiers of
lamellulae, moderately broad (4-5 mm), "russet-vinaceous" when young (medium
vinaceous-red), tinged chocolate-gray in age, pruinose under a lens from the
pleurocystidia, edges even.
Stipe 5-10 cm long, 4-6 mm thick, equal, hollow, fragile, "pale vinaceousfawn" to "light vinaceous-fawn" beneath a coating of appressed white fibrils,
appearing longitudinally fibrous-striate and canescent, becoming sordid in age.
Spores 12-15 x 6-8,u, smooth, with a distinct often oblique apical pore, shape
in face view elliptic to nearly oblong, in profile subelliptic to very obscurely
inequilateral, color in KOH dark bister and slowly darkening to dark coffeecolor, very dark vinaceous-brown under the microscope when fresh, in Melzer's
bay-red, wall about 0.4 t thick.
Basidia 4-spored, (20-)26-38x 10-15 u, hyaline in KOH, clavate-pedicellate.