North American species of Mycena.

166 NORTH AMERICAN SPECIES OF MYCENA

cystidia; pleurocystidia abundant, smooth, with pale-yellowish content, 60-70 X 8-12 A, somewhat ventricose with an elongated neck;
caulocystidia abundant, some resembling pleurocystidia and some the
roughened cheilocystidia, some variously contorted or elongated and
branched; gill trama homogeneous, dark red in iodine, pileus trama
composed of a subgelatinous pellicle made up of yellow hyphae;
tramal body dark vinaceous red in iodine.
Habit, habitat, and distribution.-Not uncommon, single or in twos
and threes on dead twigs of Rhododendron and dead stems of Leucothoe Catesbaei (Walt.) Gray; North Carolina and Tennessee.
Material studied.-Smith, 7359, 10413, 10871, 14879, 14885.
Hesler, 9694, 11479, 14186, 14228.
Observations.-The stipe of M. carolinensis revives somewhat, and
at first it seemed questionable whether or not the species should be
placed in Marasmius. Dried specimens do not revive so well as those
of M. corticola, however. This, in view of the nature of the trama
of the pileus, its reactions to iodine, and the two types of cystidia on
the gill edge, is more indicative of Mycena than of Marasmius. Dr.
Jakob E. Lange, who saw fresh material from Cades Cove, Tennessee,
pronounced it a Mycena. Although differing sharply in color, M.
carolinensis has a superficial resemblance to M. corticola. The consistency, the manner in which the stipe is attached to the substratum,
and the shape of the pileus are all suggestive of that species. It is
entirely possible that M. carolinensis at times has gills margined with
pale yellow. This would happen if the fusoid-ventricose cystidia
were more abundant than usual along the gill edge. The relationships of this species are a bit obscure, to say the least. It may possibly be related to M. viridimarginata or to M. avenacea, but because
of its consistency, a gelatinous pellicle over the pileus, and the two
distinct types of cystidia such a relationship does not seem likely.
73. MYCENA FLAVOALBA (Fr.) Quelet
Champ. Jura et Vosges, p. 103. 1872
Agaricus (Mycena) flavoalba Fries, Epicr. Syst. Myc., p. 103. 1838.
Illustrations:
Plate 19 A; Text fig. 16, nos. 4-5 (p. 170).
Bresadola, Icon. Mycol., 5, pl. 231.
Fries, Icon. Sel. Hymen., I, pl. 79, fig. 5.