Cap: 1-4 cm; variable in shape but more or less convex; convoluted; bald; with a smooth or slightly wrinkled surface; sticky or slimy when fresh, but sometimes drying out; the margin inrolled; buff, brownish yellow, yellow, or olive—not infrequently turning dark green to nearly black with age; undersurface bald and pale.
Stem: 2-8 cm long; up to 1 cm wide; bald; often adorned with tiny pale flakes; more or less equal; sticky or slimy when fresh; colored like the cap or paler; slowly bruising dark green where damaged; hollow or filled with gelatinous material.
Flesh: Gelatinous when fresh.
Spores 16-25 × 4-6 µ; narrowly ellipsoid to subfusiform; smooth; often curved; becoming septate, with 3-7 septa at maturity. Asci 8-spored. Paraphyses filiform; often forked; apices subclavate to irregularly swollen; 1-2 µ wide.