The North American species of Psathyrella.

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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN

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Habit and habitat. Gregarious on lawns.
Distribution. Cuba.
Observations. The dried basidiocarps have distinctly vinaceous, narrow,
crowded gills and the whole aspect is that of P. hymenocephala save for the
absence of a veil. Psathyrella thiersii has much the same aspect but smaller
spores and a submembranous partial veil.
248. Psathyrella castaneidisca (Murrill) A. H. Smith, comb. nov.
Drosophila castaneidisca Murrill, Mycologia 10: 63. 1918.
Illust. Text Fig. 545.
Pileus 2.5 cm broad, convex, surface hygrophanous, avellaneous, slightly
tinged with chestnut, pale chestnut on the disc, margin straight, entire, concolorous, striate. Context very thin and fragile.
Lamellae adnate, narrow, crowded, chestnut.
Stipe 3 cm long, 2 mm thick, cylindric, equal, smooth, white, furfuraceous.
Spores 7-9 (-10) x 4.6-6 [, smooth, apical pore distinct and apex truncate
though not conspicuously so, shape in face view ovate to elliptic, in profile
obscurely inequilateral to subovate, color in KOH dull cinnamon (near "Sayal
brown"), slowly darkening to near wood brown, in Melzer's tawny, wall about
0.3 pu thick.
Basidia 4-spored, 8-10 /u broad, hyaline in KOH. Pleurocystidia none. Cheilocystidia broadly cylindric to ventricose, the apex broadly rounded and the neck
only slightly narrowed, hyaline in KOH, thin-walled, readily collapsing hence
difficult to measure in the type (approximately 23-26 x9-16 u). Gill trama not
reviving in type. Pileus having a cuticle of vesiculose cells one or two deep,
the wall pale brownish to nearly hyaline and thin. Context of cinnamon-brown
hyphae but poorly revived and details of wall not reliable.
Type locality. Castelton Gardens, Jamaica.
Habit and habitat. Solitary on soil in a rubbish heap.
Distribution. Known only from the type locality.
Observations. This account is based entirely on the type and original description. The distinguishing features of the species are the chestnut colored pileus,
narrow crowded lamellae, white stipe, and the cuticle of the pileus being typically
one cell deep. Again, this species reminds one of P. hymenocephala but the spores
are wider and a veil is lacking.
249. Psathyrella australis (Murrill) A. H. Smith, comb. nov.
Atylospora australis Murrill, Mycologia 14: 266. 1922.
Pileus 1-3 cm broad, expanded, subumbonate, surface glabrous, hygrophanous,
slightly striate, pale fawn color, slightly darker on the disc. Context very soft
and fragile.
Lamellae adnexed, crowded, rather narrow, concolorous, then brownish.
Stipe 4-6 cm long, 2-3 mm thick, rigid-fragile, cylindric to slightly tapering
above, hollow, glabrous or somewhat atomaceous, pure white; veil slight, white,
all traces soon vanishing.
Spores 7-9 x 4-5 /, smooth, with apical hyaline germ pore but scarcely appearing truncate at the apex, shape in face view oblong to elliptic, in profile subelliptic to obscurely inequilateral, color in KOH pale dull brown becoming nearly
avellaneous (paler and grayer).