North American species of Mycena.

474 NORTH AMERICAN SPECIES OF MYCENA

taxonomic value. Apparently M. caesia is synonymous with M. atroalboides, but it is placed here in the excluded list because of the slight
differences in appearance between the two types as they are preserved
at Albany, New York.
Mycena caesiialba Murrill, Mycologia, 8: 220. 1920.
Prunulus caesiialbus Murrill, North Am. Flora, 9: 337. 1916.
"Pileus thin, conic to campanulate, gregarious, 1.5 cm. broad;
surface dry, smooth, glabrous, caesious with an aeruginous tint, faded
and much wrinkled on drying: lamellae adnate to the enlarged apex
of the stipe, narrow, subcrowded, arcuate, white: spores subglobose,
slightly roughened, densely granular, 7-8, long: stipe long and
slender, pruinose to glabrous, white or avellaneous at the apex, tomentose and aeruginous at the base, 6 cm. long, 1-2 mm. thick.
"Type collected among dead leaves in Preston's Ravine near Palo
Alto, California, November 25, 1911, W. A. Murrill & L. R. Abrams
1208 (herb. N. Y. Bot. Gard.).
"Distribution: Known only from the type locality."
The type consists of one complete carpophore and some fragments
of a second. I have examined it twice. The first time the fragments
were studied, but the second time the carpophore was sectioned. In
the fragments the spores were found to measure 7-8 X 6-7 ju, to be
subglobose, smooth and borne on four-spored basidia. Pleurocystidia
were scattered and similar to the cheilocystidia. The cystidia measured 32-41 X 4-8,u, were cylindric to very narrowly fusoid in shape
and thin walled. No pellicle was noted on the pileus.
In the second examination, I found the spores to be 7-9 X 5-6
(7.5),u, broadly ellipsoid, smooth, and amyloid. The basidia were
four-spored. Pleurocystidia were not located, although a careful
search was made for them. The cheilocystidia were 28-39 X 4-7 /i
and narrowly fusoid to subcylindric in outline. The pileus trama was
characterized by a thick gelatinous pellicle.
As a result of this second study it is perfectly clear to me that the
large specimen, which must be regarded as the type, is nothing more
than a carpophore of M. amicta. Just what the fragments represented, I am not prepared to say, but apparently they are not the
same as the one large carpophore. Murrill described the spores as
roughened and densely granular. Obviously he mistook as roughness
the appearance which the accumulation of numerous small oil drop