Par? 5, 1916] AGARICACEAE 315 
19. Omphalopsis californiensis Murrill, sp. nov. 
Pileus very delicate, pure-white throughout, conic to narrowly campanulate, distinctly 
umbonate, gregarious, 2.5 mm. broad and high; surface smooth, glabrous, margin entire, 
appressed when young: context white, without characteristic taste or odor; lamellae decurrent, 
broad, arcuate, distant: spores ovoid, smooth, hyaline, 7~9 X 54: stipe very slender, 
cylindric, pulverulent above, glabrous below, cartilaginous, becoming hollow, 1-2 cm. long, 
less than 1 mm. thick. 
Type collected among decaying pine needles in shady pine woods at Stanford University, 
California, November 16, 1901, C. F. Baker 92 (herb. N. Y. Bot. Gard.). 
DISTRIBUTION: Known only from the type locality. 
20. Omphalopsis McMurphyi Murrill, sp. nov. 
Pileus rather small and delicate, convex, cespitose, 5-10 mm. broad; surface smooth, 
glabrous, white, margin undulate, furrowed, appressed when young: context thin, white, with- 
out characteristic taste or odor; lamellae decurrent, subdistant, about 20 in number, rather 
broad, white: stipe cylindric, slender, hollow, white, glabrous, mycelioid at the base, 1.5-3 cm. 
long, 0.5-1 mm. thick. 
Type collected in soil, probably attached to buried wood, on the bank of Madera Creek, near 
Stanford University, California, December 21, 1902, James McMurphy 51 (herb. N. Y. Bot. Gard.). 
DISTRIBUTION: Known only from the type locality. 
21. Omphalopsis subimmaculata Murrill, sp. nov. 
Pileus small, convex, slightly depressed at the center, cespitose, reaching 8 mm. broad; 
surface smooth, glabrous, finely striate nearly to the center, pure-snow-white, margin entire, 
appressed when young: lamellae long-decurrent, distant, rather narrow, inserted, white: stipe 
very slender, cylindric, hollow, white, minutely whitish-pruinose to subglabrous, 2 cm. long, 
0.5 mm. thick. 
Type collected on dead wood in woods near Seattle, Washington, October 20~November 1, 
1911, W. A. Murrill 688 (herb. N. Y. Bot. Gard.). 
DISTRIBUTION: Known only from the type locality. 
22. Omphalopsis aurantiaca (Peck) Murrill. 
Omphalia aurantiaca Peck, Bull. Torrey Club 25: 323. 1898. 
Pileus very thin, broadly convex or subplane, cespitose, 1-2.5 cm. broad; surface glabrous, 
pale-orange, margin striatulate when moist, inflexed: lamellae thick, pale-orange, decurrent, 
distant: spores ellipsoid, 7.5 X 4: stipe short, often curved, concolorous, I-2.5 cm. long, 
1 mm. thick. 
TyPE LocALIty: Portland, Oregon. 
Hasrrat: On old fir tree logs in woods. . 
DISTRIBUTION: Known only from the type locality. 
23. Omphalopsis Bakeri Murrill, sp. nov. 
Pileus minute, delicate, broadly campanulate, gregarious, 3-8 mm. broad; surface brown- 
ish-gray on the disk, becoming lighter toward the margin, dry, glabrous, margin undulate, 
pallid, striate, appressed when young: context very thin, white, without characteristic odor or 
taste; lamellae decurrent, inserted, subdistant, rather broad, white: stipe very slender, cylindric, 
pale-brownish-gray, smooth, glabrous, except at the base, hollow, 2-3 cm. long, less than 1 mm. 
thick. 
Type collected among decaying pine needles in a shady grove at Stanford University, Cali- 
fornia, November 16, 1901, C. F. Baker 93 (herb. N. Y. Bot. Gard.). 
DISTRIBUTION: Known only from the type locality. 
24. Omphalopsis distantifolia Murrill, sp. nov. 
Pileus infundibuliform, gregarious, reaching 3 cm. broad; surface smoky-white, silky- 
fibrillose to glabrous, broadly striate-sulcate: lamellae decurrent, very distant, broad, white: 
