North American species of Mycena.

206 NORTH AMERICAN SPECIES OF MYCENA

nature of the entire fruiting body, the pale-rose colors, bordered gills,
and two different types of cystidia on the lamellae are its most distinctive characters. I have not noted the nitrous odor mentioned
by Kauffman, and I believe that he confused M. rosella with M. capillaripes. M. rosella is usually brighter in color than Peck's species
and is by no means as fragile.
SUBSECTION CILIATAE
Mycena Kauffmanii and M. rosella may be sought for in this
group. For the former see page 384; for the latter, page 204.
KEY TO SPECIES
1. Terrestrial species.............................................
1. Lignicolous species (on dead twigs above ground or on stumps, logs,
or branches)................................................ 7
2. Rather fleshy species; stipe 2-5 mm. thick........................ 3
2. Slender, membranaceous, and fragile species....................... 4
3. Spores 5.5-7 X 3-3.5........................... 88. M. pelianthina
3. Spores 7-9 (10) X (3.5) 4-5,.................. 89. M. rutilantiformis
4. Gills edged sordid fuliginous (M. Kauffmanii may key out here also)
99. M. atromarginata
4. G ills not as above......................................... 5
5. Odor nitrous; spores 7-10 X 4-5 A, (4-spored)..... 104. M. capillaripes
5. O dor not nitrous............................................... 6
6. Gill edges reddish brown; spores 11-14 X 6-8 sj (4-spored); on sphagnum.......................... 103. M. cheboyganensis
6. Gill edges reddish brown; spores 4-5.5 y wide; not on sphagnum
102. M. avenacea
6. Gill edges yellowish; spores 8-11 X 4-5.5 y.. 100. M. citrinomarginata
6. Gill edges yellowish; spores 6-8 X 4.5 g,...... 101. M. olivaceobrunnea
7. Pileus gray to grayish brown................................ 8
7. Pileus deep reddish brown, purplish lilac, or pinkish................ 9
8. Gill edges dark reddish to purplish brown..... 97. M. rubromarginata
8. Gill edges dark olive brown................... 98. M. viridimarginata
8. Gill edges grayish to fuliginous (M. marginella also keys out here)
99. M. atromarginata
9. Pileus reddish to pinkish brown; edges of gills pale pink to sordid pale
vinaceous..................................... 96. M. elegantula
9. Pileus purplish, fading, and with lilac cast when faded; gill edges at
first dark slate purple...................... 95. M. purpureofusca