North American species of Mycena.

EXCLUDED AND DOUBTFUL SPECIES

473

"Minutus, totus aleuriatus niveus; pileo conico-campanulato;
stipite filiformi; lamellis angustis adscendentibus.
"On small twigs, Devonshire Marsh.
"Scarcely a line high; stem — 1 inch high, covered, as well as the
pileus, with white mealy particles.
"Very delicate."
The fungus was found in Bermuda. Until the microscopic
characters of the type have been studied, there is no use in trying to
recognize the species. The original description is quoted.
Mycena atroalba (Bolt. ex Fr.) Gillet.
This is imperfectly known. The best European account is
Ricken's, and the concept of Beardslee and Coker (1924) is not that
of Ricken; the difference in spore size allows that much to be ascertained. Since information on the cystidia of the Asheville material
was not given, it is impossible to be certain of the identity of the
specimens.
Mycena brunneidisca Murrill, North Am. Flora, 10: 192. 1917.
Bolbitius brunneidiscus Murrill, Mycologia, 9: 320. 1917.
Mycena caesia Peck, Bull. Torr. Bot. Club, 22: 486. 1895.
Prunulus caesius Murrill, North Am. Flora, 9: 327. 1916.
"Pileus submembranous, campanulate, striate, glabrous, grayishbrown, blackish or blackish-brown in the center; lamellae thin, subventricose, grayish or bluish-gray; stem slender, hollow, glabrous,
grayish-brown; spores subelliptical, slightly apiculate at one end,.0003 to.0004 in. long,.00016 to.0002 broad.
"Pileus 4-6 lines broad; stem 1-2 in. long, 0.5 to 1 line thick.
"Among sphagnum. Newfoundland. September. Rev. A. C.
Waghorne.
"I have seen dried specimens only and am not certain that the
bluish-gray of the lamellae is so conspicuously present in the fresh
plant. The margin of the pileus is sometimes tinged with yellowishbrown."
I have examined the type and found that its microscopic characters
are identical with those of M. atroalboides Peck. The specimens are
slightly more umbonate when dried, a difference which has little