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 quite common and very widely distributed, and occurs in woods and grassy open places, during late summer and in the autumn. The entire plant is nearly of a uniform color, and the color varies from rose, to rose purple, violet, or lilac. Plants from the Blue Ridge mountains of North Carolina were chiefly rose purple, very young plants of a much deeper color (auricula purple of Ridgeway), while those collected at Ithaca were violet. The plants vary from 5-8 cm. high, the cap 2-3 cm. broad, and the stem 2-4 mm. stout. The plants are scattered or somewhat clustered, sometimes occurring singly, and again many covering a small area of ground.
Mycena pura. Entire plant rose, rose-purple, violet, or lilac. Striate on margin of pileus (natural size, often much larger).
The pileus is thin, conic, bell-shaped to convex and nearly expanded, sometimes with a small umbo, smooth, and finely striate on the margin, in age the stria1 sometimes rugulose from the upturning of the margin. Sometimes the pileus is rugose on the center. The gills vary from white to violet, rose, etc., they are adnate to sinuate, and in age sometimes become free by breaking away from the stem. They are broad in the middle, connected by vein-like elevations over the surface, and sometimes wavy and crenate on the edge, the edge of the gills sometimes white. The spores are white, oblong, 2.5-3.5 x 6-7 µ, smooth. The basidia are cylindrical, 20-25 x 3-4 µ, four-spored. .There are a few cystidia in the hymenium, colorless, thin walled, clavate, the portion above the hymenium cylindrical, and 30-40 x 10-12 µ.
The stem is sometimes white when young, but later becomes of the same color as the pileus, often a lighter shade above. It is straight, or ascending, cylindrical, even, smooth, hollow, with a few white threads at the base.
Sometimes on drying the pileus becomes deeper in color than when fresh. The gills also become deeper in color in drying, though the edge remains white if white when fresh. Figure 97 is from plants (No. 3946, C. U. herbarium) collected at Blowing Rock, N. C, in August, 1899. The plants are often considerably larger than shown in the figure. Mycena epipterygia Scop. - This pretty little species is quite readily distinguished by the gray, conic or bell-shaped cap, the long, hollow, slender stem, and the viscid pellicle or skin which is quite easily peeled off from the stem or cap when moist. It grows in woods or grassy places, or among moss, etc., on the ground or on very rotten wood. The plants are from 5-10 cm. high, the cap 1-2 cm. broad, and the stem about 2 mm. in thickness. It is widely distributed in Europe, America, and other North temperate countries.
Mycena epipterygia. Cap viscid, grayish, often tinged with yellowish or reddish in age, gills white, sometimes tinged with blue or red, stem yellowish, or same color as cap (natural size). Copyright.
The pileus is viscid when moist, ovate to conic or campanulate, and later more or less expanded, obtuse, the margin striate, and sometimes minutely toothed. The usual color is grayish, but in age it often becomes reddish. The gills are decurrent by a small tooth, and quite variable in color, whitish, then gray, or tinged with blue or red.
The stem is very slender, flexuous, or straight, fistulose, tough, with soft hairs at the base, usually yellowish, sometimes the same color as the cap, and viscid like the cap when moist. Figure 98 is from plants (No. 4547, C. U. herbarium) collected at Ithaca in August, 1899.