North American species of Mycena.

468 NORTH AMERICAN SPECIES OF MYCENA

locate. Upon a casual observation one would pronounce most of the
cystidia smooth. The tramae of the pileus and gills were slightly
reddish in iodine.
I suspect that this fungus, when restudied from fresh material,
will be found to resemble 0. campanella in many of its characters
and that it should be placed in Xeromphalina if that genus is considered distinct from Omphalia.
OMPHALIA MYCENIFORMIS Murrill
Mycologia, 8: 220. 1916
Omphalopsis myceniformis Murrill, North Am. Flora, 9: 316. 1916.
"Pileus thin, convex, not expanding, solitary, 12 mm. broad;
surface glabrous, dry, stramineous with a grayish tint, margin striate,
satiny, deflexed, entire: lamellae short-decurrent, inserted, ventricose, broad, subdistant, white: spores globose, smooth, hyaline, 5-7 g:
stipe long, tough, curved, smooth, glabrous, pale-reddish-brown,
3 cm. long, 1 mm. thick."
Type collected on humus in Tepeite Valley near Cuernavaca,
Mexico. It consists of one well-preserved carpophore. The spores
measure 3-4 X 2-2.5,t, are hyaline in KOH, smooth, and bluish in
iodine (amyloid). The basidia are four-spored. Pleurocystidia and
cheilocystidia are present, measure 30-40 X 7-192 u, and are of the
smooth fusoid-ventricose type. The tramae of the pileus and gills
are each subgelatinous and appear somewhat "glassy" in KOH.
This species is apparently related to 0. convexa, 0. roriduliformis,
and 0. subavellanea by virtue of its tramal character and small amyloid
spores.
In 0. convexa the pileus and gill tramae are each distinctly subgelatinous or "glassy" in KOH, the spores 4-4.5 X 2-2.5, and amyloid, the basidia are four-spored, and pleurocystidia and cheilocystidia
are not differentiated. The fruiting bodies revive well and remind
one of those of Marasmius. 0. roriduliformis has the same appearance and tramal characters as 0. convexa. Its spores are 3-4 X 2.5,
and amyloid. Cheilocystidia varying from the fusoid-ventricose type
to the more or less clavate-contorted type were present. 0. subavellanea has a pileus with a gelatinous pellicle, but the remainder
of the trama of the pileus and also that of the gills are "glassy" in KOH
and hence at least subgelatinous. Its spores are 3.5-4 X 2.5 j and
amyloid. Its cheilocystidia are irregular to clavate and have more
or less roughened apices. These species appear to form a fairly dis