222 NORTH AMERICAN FLORA [VOLUME 9 
63. Russula mexicana Burl. Mycologia 3: 26. 1911. 
Pileus convex to depressed, 6 cm. broad; stirface pale-red, dry, with inseparable pellicle, 
smooth; margin striate: context white, 5 mm. thick at the center, promptly and decidedly 
acrid; lamellae white when young, becoming pale-yellow at maturity, equal, simple, adnate; 
stipe roseous, cylindric, glabrous, 4 cm. long, 2 cm. thick: spores pale-yellow, subglobose, 
echinulate, 7-8 » in diameter; cystidia numerous. 
Type LocaLity: Near Jalapa, Mexico. . 
Hapitat: On humus under the end of a log in rather open woods. 
DISTRIBUTION: Known only from the type locality. 
XV. Palustres. Pileus with separable pellicle; surface viscid when wet, glabrous; 
margin striate when mature: context white, fragile, acrid, without special odor; lamellae 
equal, not forking: spores pale-yellow. 
64. Russula palustris Peck, Ann. Rep. N. Y. State Mus. 53: 842. 
1900. 
Pileus hemispheric, expanding and becoming nearly plane, 5-7.5 cm. broad; surface 
tinged with slate-violet or in the center vinous-purple surrounded by yellowish, viscid when 
moist, with separable pellicle, glabrous; margin slightly striate when mature: context white, 
tinged with reddish-buff under the cuticle, fragile, tardily acrid; lamellae whitish, becoming 
pale-yellow, equal, venose-connected, narrowed at the stipe, not forking unless close to the 
stipe, close; stipe white or tinged with slate-violet or yellowish, equal, spongy or hollow, 
glabrous, 2-7.5 cm. long, 0.7-1 em. thick: spores pale-yellow, subglobose, echinulate, 7.6— 
8.5 X 8.5-11.5 uw. 
TYPE LOCALITY: St. Lawrence County, New York. 
Hasitat: Under alders in swamps. 
DistRIBUTION: Maine, New York, and Vermont. 
65. Russula gracilis Burlingham, sp. nov. 
Pileus convex, becoming plane or at length slightly depressed in the center, up to 6 cm, 
broad; surface pale-lilac-rose to salmon-lilac, much darker in the center, sometimes gray- 
green or stone-color between the center and margin, fading, viscid when wet, with separable 
pellicle, glabrous; margin striate: context white, acrid, without special odor; lamellae white, 
then cream-colored, equal, entire, rounded at the outer ends, narrow behind, appearing slightly 
decurrent when mature, rather broad, close, pruinose; stipe white, rarely tinged with pink, 
tapering upward, spongy within, 5 cm. long, 0.8 to 2 cm. thick: spores pitchpin, globose to 
elliptic, echinulate, with vacuole, 7 X 7-9 n. ~ 
Type collected among weeds in maple, spruce, and willow woods bordering a stream at Stratton, 
Vermont, August, 1910, Gertrude S. Burlingham 212-1910 (herb. Burlingham; extype herb. N. Y. 
Bot. Gard.). 
DISTRIBUTION :-“Known only from the type locality. 
XVI. Glaucae. Pileus with pellicle separable, some shade of green, viscid when wet, 
glabrous; margin even to slightly striate when mature: context white, unchanging, mild, 
without special odor; lamellae mostly equal, some forking near the stipe: spores pale-yellow. 
66. Russula glauca Burlingham. 
Agaricus griseus Pers. Syn. Fung. 445. 1801. Not A. griseus Batsch, 1783. 
Russula grisea Fries, Epicr. Myc. 361. 1838. 
Russulina grisea Schrét. Krypt.-Fl. Schles. 31: 551. 1889. 
Pileus fleshy, firm, convex, then expanding, finally depressed in the center, up to 9 cm. 
broad; surface varying in color from glaucous to leaden-green or slate-green intermingled with 
a tinge of rosy-flesh to salmon-flesh or even maize-yellow, fading, viscid when wet, the pellicle 
separable half way to the center, having a pruinose bloom when young; margin even at first, 
at length faintly and finely striate on the very narrow edge: context tinged like the surface 
next to the cuticle, otherwise white, thin, mild in taste, without special odor ; lamellae white, 
