Russula atroviolacea Burl. 1915

Russula atroviolacea Burlingham, sp. nov
Pileus convex, then plane and depressed in the cent^, 4-9 cm. broad; surface haematitered or diamine-brown, uniformly colored or rarely lighter in the center, viscid when wet, with separable peUicle, glabrous; margin even: context fleshy, solid, not fragile but thin, piuT)lish under the cuticle, otherwise white, tardily and slightly peppery; lamellae cream-colored, darker with age or in drying, mostly equal, branching somewhat next to the stipe, interspaces venose, rather close, adnate, 6-10 mm. broad; stipe equal or slightly larger below, white, not discolored, slightly pruinose to glabrous, solid, becoming hollow, at least at the base, 4-6 cm. long, 1.5-2 cm. thick: spores ochraceous, globose, echinulate, 7-10 fi in diameter.
Type collected on the ground under willows at Boulder Park, Tolland, Colorado, 2775 m. elevation, July 14, 1914, L. 0. Overholis 1909 (herb. Overholts; extype herb. Burlingham), Distribution: Known only from the type locality.