North American species of Mycena.

EUMYCENA: LAC TIPEDES

143

is the commonest and the most easily recognized one in the genus.
It can be found during the spring, summer, and fall months in the
northern areas and very likely throughout the winter where weather
conditions are favorable.
Material studied.-Smith, 32-226, 32-283, 32-314, 131, 228, 482,
514, 1032, 2568, 4383, 4674, 6309, 6390, 7016, 7071, 7249, 8194, 8249,
8317, 8373, 8486, 8821, 10869, 10937, 13262, 13397, 13609, 13706,
13770, 13773, 16574, 17308. Atkinson, numerous collections, numbers not recorded. Bisby, July 6, 1932. Brown, October 1, 1925.
Flett, June 3, 1935, and 1941, Washington. Gruber, Oregon. Hesler, 2486, 12321. Kauffman, New York, Michigan, Idaho, Washington, and Oregon. Kelly, 1093, Ontario. Mains, 34-139, 32-433,
5028. Morse, August 28, 1930, California. Overholts, 800, 895,
1532, 1533, 4253. Povah, 7, Florida. Routien, 1059. Wehmeyer,
726, 726a, 726b.
Observations.-The dull-red to reddish-brown colors, habitat on
wood, crenate margin of the pileus, fusoid cystidia, and densely
grayish-pruinose cap and stipe (when young), as well as dark bloodred juice, readily distinguish this species. Although very easily
recognized, it contains many intergrading forms. Its stature varies
with the substratum, the nutrient, and the climatic conditions.
Along our Pacific coast it often attains gigantic proportions for a
Mycena. Such characters as the density and color of the pruinosity
and the colors of all parts of the carpophore also depend on the
growing conditions, being generally much more striking in robust
individuals. The spore size likewise is variable. Large specimens
with spores 9-12 X 5-7 Ag have been found as well as specimens with
spores 7-8 X 4-5 y. The latter are rare. Were it not for the fact
that the great majority of specimens have a spore range intermediate
between these two, both might be considered worthy of taxonomic
recognition. The pleurocystidia vary in number in much the same
manner as those of M. alcalina. I have always been able to find at
least a few on any specimens examined. In some collections they are
abundant.
59. MYCENA HAEMATOPUS var. MARGINATA Lange
Dansk Bot. Arkiv., 1 (5): 20. 1914
Illustrations:
Plate 15.
Lange, Flora Agar. Dan., 2, pl. 50 D.