The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

[VOL. 24

51. Psathyrella candolleana (Fries) Maire, Mem. Soc. Sci. Nat. Maroc. 45: 113.
1937.
Agaricus candolleanus (as candollianus) Fries, Syst. Mycol. 1: 296. 1821.
Hypholoma candolleanum (as candollianus) (Fr.) Quelet, Champ. Jura et Vosges,
146. 1872.
Drosophila candolleana (Fr.) Quelet, Enchir. Fung. 115. 1886.
Psathyra candolleana (Fr.) Bertrand, Bull. Soc. Mycol. Fr. 17: 278. 1901.
Hypholoma cutifractum (as cutifracta) Peck, Bull. Torrey Club 22: 490. 1895.
Hypholoma inocybeforme Kauffman, Pap. Mich. Acad. Sci. 11: 193. 1930.
var. candolleana
Illust. Pls. 24, 25, 26; P1. 23, fig. a, annulate specimens; Text Figs. 131-133.
Pileus 3-7(-11) cm broad, obtusely conic to convex when young, usually
expanding to broadly convex or plane, or with an obtuse umbo and a spreading
margin, occasionally remaining broadly conic, surface moist, smooth to slightly
rugulose, the margin translucent striate, at first with scattered superficial patches
of fibrils or squamules present only near the margin, the margin appendiculate
with veil fragments, color at first light to dark honey-color ("chamois" to "buckthorn brown"), gradually becoming dingy purplish brown at least near the margin
as spores mature, hygrophanous and fading to whitish or retaining a tawny-buff
disc. Context thin, fragile, moist and concolorous with pileus at first, pallid when
faded, odor and taste mild.
Lamellae close to crowded (54-57 reach the stipe), 2-3 tiers of lamellulae,
narrow (2-5 mm), white to pallid and finally becoming grayish brown tinged more
or less with violet (often "drab"), the edges whitish and crenulate.
Stipe (4-)6-10(-13) cm long, (3-)4-8(-10) mm thick, equal more or less or
narrowed at the base, hollow, fragile, white to whitish, apex silky-fibrillose to
somewhat furfuraceous, sometimes striate, lower portion more or less fibrillosescaly to appressed fibrillose, the veil remnants soft and white-fibrillose to submembranous, usually soon evanescent, at times forming a persistent membranous
annulus.
Spores in deposit purplish brown, 7-9(-10) x 4-5 I, smooth, truncate at apex
from a hyaline pore, shape in face view elliptic to slightly ovate, in profile subelliptic to very slightly bean-shaped, color in KOH dull cocoa-color changing to
pale purplish gray, in Melzer's pale tawny to dull reddish brown, wall about 0.3 pu
thick.
Basidia 20-24x5-7 a, 4-spored, hyaline in KOH. Brachybasidioles not differentiated. Pleurocystidia not differentiated. Cheilocystidia 32-46 x 9-16 /, saccate to clavate or cylindric, occasionally the lower portion slightly ventricose,
apex broadly rounded to obtuse or knob-like at times, wall thin, smooth and
hyaline, content not distinctive. Caulocystidia versiform, up to 60x 15 ap, subutriform to utriform, clavate or vesiculose, all thin-walled, smooth and hyaline,
cell content not distinctive.
Pileus with a cuticle of vesiculose cells 1-3 deep, the walls thin, smooth and
hyaline, cell content not distinctive, measuring 20-46x 10-38 p.. Hyphae of the
trama brownish in KOH when first revived or hyaline, soon fading to hyaline,
walls smooth and thin. Clamps present. No distinctive color changes in any tissue
as revived in Melzer's.
Type locality. Europe.
Habit and habitat. Cespitose to gregarious around old hardwood stumps or
buried wood, particularly common around cottonwood and elm, spring and early
summer.