This section is from the book "Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc.", by George Francis Atkinson. Also available from Amazon: Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc..
This plant is very closely related to M. galericulata, and has the same habit. It might be easily mistaken for it. It is easily distinguished by its peculiar bright, shining, longitudinally striate to sulcate stem. It usually grows on wood, but does occur on the ground, when it often has a very long stem. In this condition it was described by Peck in the 23rd Report, N. Y. State Mus., p. 81, as Mycena praelonga, from plants collected in a sphagnum moor during the month of June. This form was also collected at Ithaca several times during late autumn in a woods near Ithaca, in 1898. The plants are from 12-20 cm. high, the cap 1-2 cm. broad, and the stem 2-3 mm. in thickness.
Mycena polygramma, long-stemmed form growing on ground (=M. praelonga Pk.). Cap dark brown with a leaden tint, striate on margin; stem finely and beautifully longitudinally striate (natural size). Copyright.
The pileus is first nearly cylindrical, then conic, becoming bell-shaped and finally nearly expanded, when it is umbonate. It is smooth, striate on the margin, of a dark brown color with a leaden tint. The gills are narrow, white, adnate and slightly decurrent on the stem by a tooth. The very long stem is smooth, but marked with parallel grooves too fine to show in the photograph, firm, hollow, somewhat paler than the pileus, usually tinged with red, and hairy at the base. Figure 96 is from plants (No. 3113 C. U. herbarium), collected in a woods near Ithaca in damp places among leaves. A number of the specimens collected were attacked by a parasitic mucor of the genus Spinellus. Two species, S. fusiger (Link.) van Tiegh., and S. macrocarpus (Corda) Karst., were found, sometimes both on the same plant. The long-stalked sporangia bristle in all directions from the cap.