The North American Species of Pholiota

164. Pholiota gregariiformis (Murr.) comb. nov.

Hebeloma gregariiforme Murrill, North Amer. Fl. 10: 217. 1917.

Illustrations: Text figs. 359-361; pl. 59b.

Pileus gregarious, 1-3.5 cm broad, convex to expanded, "light-buff" or pale yellowish brown with tints or stains of pale orange-brown, sometimes slightly darker on the disc, viscid, pellicle adnate, glabrous except for veil remnants on the even margin. Context whitish to watery brown; odor mild, taste slightly bitter.

Lamellae adnate or slightly sinuate, "olive-buff" or pale olivaceous at first, becoming yellowish brown, "buffy-brown" or "Isabella color," close, rather narrow, broad next to stipe, and subtriangular, several times inserted, edges fimbriate.

Stipe 4-6 cm long, 2-4 mm thick, at first whitish, then dingy, with scattered fibrils, tapering downward, tubular. Veil slight, arachnoid, evanescent.

Spores (6) 7-9 x 4.5-5.5 µ smooth, apical pore present but apex not truncate, shape in face view ovate to (rarely) subelliptic, in profile inequilateral, color in KOH near cinnamon-brown to tawny, paler in Melzer's reagent, wall about 0.25 µ thick.

Basidia 23-28 x 6-7 µ, 4-spored, narrowly clavate, yellow in KOH and in Melzer's reagent. Pleurocystidia 38-60 x 6-12 µ, narrowly fusoid-ventricose, apex obtuse, wall thin and smooth, content homogeneous, mostly yellow fading to hyaline in KOH, (often a plug of yellow colloidal material in neck). Cheilocystidia 30-50 x 6-9 (14) µ, similar to pleurocystidia but neck not as elongated. Caulocystidia 38-55 x 6-13 µ more or less like the pleurocystidia, not readily demonstrated at times from dried material.

Gill trama of floccose subparallel hyphae with both short and elongated cells 4-12 µ diam., their walls thin smooth and hyaline to yellowish in KOH; subhymenium a gelatinous layer of somewhat interwoven hyphae 2-3.5 µ diam. and hyaline revived in KOH. Pileus cutis a thin pellicle of somewhat gelatinous hyphae mostly ochraceous in KOH and smooth to incrusted slightly, 2-3 µ diam.; hypodermial region of floccose rusty-fulvous hyphae (revived in KOH), walls of some of the cells incrusted and cells variable in diameter to 15 µ. Context hyphae closely interwoven, cells becoming inflated, walls thin, yellowish (in KOH) and smooth. Clamp connections present. All hyphae inamyloid.

Habit, Habitat, and Distribution: On soil, in pine woods Alabama, Georgia, and Tennessee, November-December.

Observations: This is related to P. pulchella, which has yellow fibrillose veil-remnants as scales, context "olive-buff" to greenish watery gray, horizontal gills, and smaller spores. The colors, together with the downward tapering of the stipe, help in field identification of P. gregariiformis. It is close to P. tottenii, which has a darker pileus, pale buff flesh, gills broad (not subtriangular) and at first melleous, and stipe shorter.

Material Examined: ALABAMA: Hesler 22260; Murrill (type); GEORGIA: Hesler 22233; TENNESSEE: 22565.