North American species of Mycena.

152 NORTH AMERICAN SPECIES OF MYCENA

gin becoming wavy, surface pruinose at first, moist and shining at
maturity, translucent-striate along the margin, chalk white to creamy
white at first or the disc more yellowish, fading to chalk white or
retaining yellowish tints; flesh thin, pliant, and cartilaginous, white,
odor and taste not distinctive; lamellae bluntly adnate, horizontal or
only slightly ascending at first, horizontal in age and then slightly
decurrent, narrow, close, pure white, edges white and somewhat
eroded; stipe 2-4 (8) cm. long, 1-2 mm. thick, base rooting in the
decayed wood (3 cm. i), strigose and with adhering debris, equal,
cartilaginous, tubular, pure white, covered at first with a dense white
pruinose coating, somewhat glabrescent in age.
Spores 8-10 (11) X 4-5 pt, smooth, subventricose to subfusoid,
yellowish in iodine; basidia two- and four-spored; pleurocystidia and
cheilocystidia similar, very abundant, 28-42 X 5-8,, narrowly
fusoid-ventricose with rather acute apices, the tips frequently incrusted with a globular mass of a resinous substance; gill trama of
slender branched hyphae, yellowish in iodine; pileus trama homogeneous, of slender hyphae, yellowish in iodine, surface covered with
a turflike cuticle of slender cystidia 28-60 X 5-8 a, which are subfusoid to cylindric and occasionally have a resinous incrustation;
caulocystidia similar to the pilocystidia.
Habit, habitat, and distribution.-Gregarious to subcespitose on
decaying wood. I have found it in Michigan during June. According to my experience, it is rare, although Kiihner reports it as common
around Paris.
Material studied.-Smith, 15061, 18659, June 24, 1935, Michigan.
Observations.-Kiihner's interpretation (1938) of this species has
been followed. The fungus is very similar to M. delicatella in many
of its characters, but is easily distinguished because of its broader
spores. In my specimens the gills were close and narrow, and the
margin of the pileus was distinctly incurved. In these respects they
differ slightly from European species. In M. delicatella these characters are rather variable, so that little emphasis has been placed on
them here. M. olida var. americana has much the same consistency
and color but both its spores and cystidia should readily distinguish
it. Both grow in the same habitats and fruit at the same time. I
have not found a fungus of this type with the fragrant odor mentioned
by Coker in his notes (Beardslee and Coker [1924]), and Kiihner has
not admitted the specimens of Coker in his concept.