Melanoleuca portolensis Murrill 1915

Melanoleuca portolensis Murrill, Mycologia 5: 219. 1913
Tricholoma portolense Murrill, Mycologia 5: 223. 1913.
Pileus rather thick, convex with a prominent umbo, becoming nearly plane, scattered, 6-11 cm. broad; surface smooth, moist, glabrous, brownishgray, darker toward the center, margin entire, concolorous ; context white, with a slightly nutty taste but without characteristic odor; lamellae rather narrow, slightly sinuate, plane, several times inserted, crowded, white; spores ellipsoid, smooth, hyaline, 5-7X2.5-3.5 x stipe tapering upward from an enlarged base, nearly white, smooth above, somewhat roughened below, glabrous, solid, 6-8 cm. long, 1.5-2 cm. thick; veil rudimentary, leaving a trace upon the stipe.
Type locality : Portola, California. Habitat: On the ground under redwoods. Distribution : Known only from the type locality.