The gills vary decurrent and rounded according to situation. Odor and taste bitter. There are two forms: _a._ Pileus irregular, fibrillose round the margin; gills at first dingy-pallid. _b._ Salicicola, pileus somewhat convex, smooth, rarely at the first downy-scaly; gills at first yellowish-pallid. _Fries._ =Spores= subelliptical, 8×5µ _K._; 8–10×5–6µ _Peck_. New York, swampy woods about base of alders, October, _Peck_, Rep. 35; at base of alders, with adnate gills, and on birch stumps, with the gills rounded behind, Rep. 39. Mt. Gretna, Pa., New Jersey, mixed woods, August to November, 1898, _McIlvaine_. Gregarious and in loose tufts, not plentiful. It is a pretty plant, usually of a bright yellow, sometimes darker at the center of cap. Traces of an evanescent fibrillose ring are occasionally found or the fibrils adorn the margin of the cap. The gills next to the stem are either rounded, attached or slightly decurrent. Raw the taste is slightly bitter. This disappears in long cooking. =F. fla´vida= Schaeff. (Pers.)—_flavidus_, light yellow. =Pileus= fleshy, thin, broadly convex or nearly plane, glabrous, moist, pale yellow. =Flesh= whitish or pale yellow, taste bitter. =Lamellæ= moderately close, adnate, pale or yellowish becoming rust-color. =Stem= equal, often more or less curved, hollow, fibrillose, whitish or pale yellow, with a white mycelium at the base. =Spores= 8×5µ. =Pileus= 1–2 in. broad. =Stem= 1–3 in. long, 1–3 lines thick. Decaying wood of various trees. Commonly in wooded or mountainous districts. Summer and autumn. Our specimens were found on wood of both coniferous and deciduous trees. The plants are sometimes cespitose. The pileus becomes more highly colored in drying. The spores are pale rust-colored approaching ochraceous. In Sylloge the spores of this species are described as pale yellowish. _Peck_, 50th Rep. N.Y. State Bot. =Spores= broadly elliptical, 6–8×5µ _Massee_. New York, decaying wood, _Peck_, Rep. 32, 50; _Mrs. E.C. Anthony_, August. West Virginia, 1881–1885; Mt. Gretna, Pa. August to October. _McIlvaine._ F. flavida is a frequent species, gregarious and tufted on decaying wood, either standing, fallen, or as roots in the ground. The texture and substance are good. The slight bitter when raw disappears in cooking. The caps, only, are tender. SAPIN´EI. Gills and spores yellowish, etc.