384 BOTANICAL GAZETTE [NOVEMBER 
stipe furnished with a ring and of the same substance as the pileus: 
volva large, white, with a thick margin: spores white. 
The ring and volva, together with the very decided decurrent gills (upon 
which character the generic name is based), are telling characteristics of this 
genus of the Leucosporae. 
C. evanescens, sp. nov.—Pileus 13 cm. broad, white, deep cream in 
center, broadly convex to nearly plane, smooth, damp, broadly elliptical 
in outline; margin entire: flesh whitish, compact, thick in center, 
thinner near margin: lamellae very decurrent, short ones intermixed 
with long ones, white, 2-3 cm. wide near margin of pileus, becoming 
narrowed near and on stipe, subdistant, edges acute: stipe very short, 
thick, 1 cm. long, 4 cm. thick, fleshy, hollow, smooth, white; annulus 
delicate, evanescent, situated on stipe just below gills: volva large, 
white, smooth, opening around top leaving a thick even white margin, 
persistent and closely embracing base of stipe: base large, white, bul- 
bous: spores white, smooth, elliptic to fusiform, 14-17.5X3-5 #-— 
Whole plant when dried becomes a rich ochre with reddish tinge. 
Habitat: Open balsam and spruce woods, occurring singly in sod on thick 
humus; Brooklyn Lake, Wyoming, Snowy Range, alt. 3500 meters, Septem- 
ber 8, 1999, no. 88. 
Clitocybe pruinosa, sp. nov.—Pileus 3.5 cm. wide, plano-convex 
to slightly depressed, rich reddish brown over salmon, paler at margin, 
dry, smooth, shining: margin turned down and entire: flesh compact, 
white, tinged with color of cap: lamellae thin, narrowing behind, salmon 
yellow, close, very decurrent, becoming somewhat powdered with 
numerous white spores: stipe fleshy, 5 cm. long, 1 cm. wide, concolorous 
but lighter than cap, hollow, smooth: spores white, spiny, globose, 
7-10.5 ph. Ses 
Habitat: Pine humus, open pine woods; Foxpark, Wyoming, August 
14, 1909, no. 83. 
COLLYBIA MACULATA moschata, var. nov.—Pileus fleshy, firm, 6 — 
wide, convex to nearly plane, white, glabrous, shining, becoming Ung’ 
or stained with pinkish red blotches, disk sometimes broken up into 
large polygonal plates; margin turned down and even; flesh white, com- 
pact, tinged with pink just beneath the surface: lamellae whitish, in one 
specimen a faint pink tinge, adnexed to nearly free: stipe stout, firm: 
3 cm. long, 2 cm. wide, swollen in middle, stuffed, becoming hollow, 
curved, narrowed at base, striate, slightly roughened by broken fibers, 
spores white, smooth, sometimes with a slight point at one end, 7*4#-—~ 
It has a strong, almost overpowering odor of musk. : 
