Summary:
Section Typicae (Smith), Section Mycena (Maas Geesteranus). Mycena galericulata is a relatively large Mycena with cap that is convex to flat when old and thus could be mistaken for a Gymnopus or Rhodocollybia. It is typified by a cap often pale in color, yellowish gray-brown, or sometimes darker brown or with a pinkish tinge; frequently long rooting stem; and growth scattered or in small loose clusters on wood. Maas Geesteranus noted considerable confusion and redescribed a neotype based on material from the same area where original type found in Europe: the following is derived from his description except where noted.

Cap:
1-6cm across, conic to bell-shaped, "more or less pronouncedly umbonate, umbo sometimes truncate or depressed, frequently with a concentric depression around umbo", cap becoming almost flat when old, margin incurved at first, then drooping, finally upturned, sometimes fissured; usually yellowish gray-brown at center, but also paler or darker date brown, dark sepia brown, brownish flesh-color, or almost burnt sienna, with age sometimes becoming much paler, nearer the margin pale dingy yellowish brown, dingy yellowish gray, pale dingy incarnate to yellowish incarnate; lubricous when wet, bald, dull to somewhat shiny, translucent-striate, shallowly sulcate [grooved] to conspicuously rugose [wrinkled]

Flesh:
thin except at center, up to 0.15cm, pliant-tough; pale watery gray-brown, darker under cap surface, drying pallid

Gills:
adnate to emarginate, ascending, up to 0.8cm broad, 20-39 reaching stem, elastic-tough, sometimes misshapen, anastomosing or forked, smooth becoming veined, often with cross veins between; white to whitish or suffused with grayish or sepia shades, not infrequently turning pale incarnate to pink, edges colored as face or whitish, (Maas Geesteranus), close to subdistant, 26-36 reaching stem, (Smith)

Stem:
4.5-11.5cm x 0.15-0.6cm, equal or widened below, hollow, cartilaginous, elastic-tough, round in cross-section or compressed, straight to curved, penetrating substrate with a thick root up to 6cm long; very dark sepia gray-brown when young, soon becoming white to watery whitish at top, yellowish gray-brown to paler or darker gray-brown farther below; surface sometimes twisted, innately fibrillose, smooth, minutely pruinose near apex, bald for the greater part, somewhat shiny, base more or less densely covered with coarse, woolly, whitish fibrils

Odor:
none, faint, farinaceous, of fresh grass, radish-like, rancid, disagreeable, or nauseous

Taste:
none, farinaceous, of cucumber, sometimes very strong

Microscopic spores:
spores 9-12.5 x 6.3-8.5 microns: for 2-spored basidia (9)10-12.5 x 7-8.5 microns, for 4-spored 9.4-12.1 x 6.3-7.2 microns, broadly pip-shaped [elliptic], smooth, amyloid; pleurocystidia absent, cheilocystidia 20-55 x 5.5-18 microns, forming a homogeneous sterile band, "clavate to more or less irregularly shaped, not infrequently proliferating and forming new heads laterally or apically, without a clamp (2-spored basidia) or clamped (4-spored basidia), covered with a few to fairly numerous, unevenly spaced, rather coarse, cylindrical, simple to branched, usually curved excrescences" 2-25(35) x 1.3-2.5 microns, (Maas Geesteranus)

Spore deposit:
white (Arora)

Notes:
Smith(1) examined collections from WA, OR, MB, ON, AL, IL, MA, ME, MI, MO, NY, PA, TN which he ascribed to this species, and gives distribution of M. rugulosiceps as WA, OR, CA, of M. radicatella as NS, ON, MI, NY, TN, and of M. magna as WA, OR, all of which Maas Geesteranus synonymizes with Mycena galericulata. Mycena galericulata has also been reported from Iceland, India, and Japan (Maas Geesteranus). There are collections from BC at the Pacific Forestry Centre and the University of British Columbia. There is a collection from ID at the University of Washington.

EDIBILITY

[yes according to some sources, but not recommended because relatives untested]

Synonyms and Alternate Names:
Mycena magna (Murrill) Murrill
Mycena radicatella (Peck) Sacc.
Mycena rugulosiceps (Kauffman) A.H. Sm.