The flesh is thin, gray, cartilaginous and tough, with a strongly farinaceous (mealy, similar to raw potatoes) odor and taste if crushed or chewed. The whitish to grayish gills are moderately broad (2–3 mm) with a spacing that is close to subdistant, and 18–26 reach the stipe, interspersed with two or three tiers of lamellae (short gills that do not extend fully from the cap margin to the stipe). The stipe attachment is adnate or arcuate, but later develops a pronounced decurrent tooth. The decurrent tooth occasionally separates from the stipe and forms a collar around it. The stipe is long, thick, equal in width throughout, hollow, cartilaginous, and brittle. The stipe surface is smooth or polished, with the apex initially faintly pruinose (as if covered with a fine whitish powder). The base of the stipe is sparsely covered with sharp, straight, stiff hairs, and is the same color as the cap or paler. The mushroom is inedible. The spores are 7–9 by 4–5 μm, ellipsoid, smooth, amyloid (reaction very weak in some collections). The basidia (spore-bearing cells) are four-spored, or occasionally a combination of two- and four-spored. The four-spored forms have clamp connections that are absent in the two-spored forms. The pleurocystidia (cystidia found on the face of the gills) are not differentiated. The cheilocystidia (cystidia found on the edges of the gills) are embedded in the hymenium and inconspicuous, measuring 22–36 by 5–11 μm. They are roughly filiform (like thin filaments), with numerous contorted branches or protuberances, and club-shaped with finger-like prolongations. The flesh of the gills is homogenous, and turns vinaceous-brown when stained in iodine. The flesh of the cap has a well-differentiated pellicle, with a differentiated but not very well-developed hypoderm, and hyphae that are 10–20 μm wide. "Mycena cinerella" is a saprobic fungus, and derives nutrients by decomposing leaf litter and similar detritus, converting it to humus and mineralizing organic matter in the soil.