The North American Species of Pholiota

131. Pholiota condensa (Pk.) comb. nov.

Flammula condensa Peck., Bull. Torrey Club 33: 217. 1906.
Gymnopilus condensus (Pk.) Murrill, North Amer. Fl. 10: 198. 1917.

Illustrations: Text figs. 279-280.

Pileus 2-3 cm broad, convex or nearly plane, often irregular from its densely caespitose mode of growth, usually umbonate, brownish yellow, the umbo reddish brown or chestnut colored, viscid when fresh. Context white, often tinged with yellow.

Lamellae adnate or slightly decurrent, yellowish becoming brownish ferruginous, moderately broad, subdistant, sometimes rugosely wrinkled.

Stipe 2-4 cm long, 2-3.5 mm thick, apex yellowish, pallid or brownish toward the base, equal, hollow.

Spores 7-9 (10) x (3.7) 4-5 µ, smooth, apical pore distinct but apex not truncate; shape subelliptic to ovate (rarely obscurely angular) in face view, varying from obscurely bean-shaped to obscurely inequilateral in profile, tawny to ochraceous-tawny in KOH, in Melzer's slightly more cinnamon-color, wall about 0.3 µ thick.

Basidia 20-25 x 5.5-7.5 µ, 4-spored, clavate, yellowish in KOH and in Melzer's reagent. Pleurocystidia 48-72 x 7-14 µ, fusoid-ventricose, apex usually obtuse, neck undulating, walls smooth or coated with amber-brown amorphous coating, thin-walled or wall up to 0.4 µ thick, content often amber-brown in KOH but fading to yellowish on standing, rarely with any inclusions such as rod-like particles but colloidal material evenly dispersed and evident in the neck of many. Cheilocystidia 30-50 x 6-12 µ, fusoid to fusoid-ventricose, otherwise similar to pleurocystidia. Caulocystidia none except at apex where hymenium extends for a short distance on the stipe and cells there similar to hymenial cystidia.

Gill trama of a central area of yellowish floccose hyphae as revived in KOH, and a distinct gelatinous subhymenium. Pileus cutis a gelatinous pellicle 3-6 hyphae deep, the hyphae 2-3.5 µ with walls gelatinizing, yellowish in KOH; hypodermial region of highly colored floccose compactly arranged hyphae either smooth or with incrustations on the wall. Clamp connections present. All hyphae inamyloid.

Habit, Habitat, and Distribution: Caespitose, in pine clearings and on stony hills, District of Columbia, December, type studied.

Observations: Peck (1906) stated that the pileus is viscid and we have demonstrated a typical gelatinous pellicle on some of the specimens in the type collection. Since the material even though appearing to be fairly well dried revives poorly, negative results in demonstrating the pellicle are to be expected by ordinary techniques—the pellicle may be torn off or simply not revive. By heating sections in KOH (2.5%) however, we demonstrated its presence conclusively. The species has all the features of the P. spumosa group, and indeed, has spores the size of European material of P. spumosa. The only discordant anatomical feature is the rather thin pellicle. Because of the terrestrial habitat the thin pellicle, and cystidia with slightly thickened walls, we recognize this species in this Section.

Material Examined: Peck (type, from near Washington, D. C., December, collected by F. J. Braendle).