1914] 
OVERHOLTS— THE РОГУРОВАСЕЖ OF OHIO 145 
ing lamellate in old plants, 0.5-1.5 mm. broad; spores white, 
smooth, oblong, mostly curved, 1.5-2 x 6.2-7.5 u. 
On dead wood or on living trees, especially of байх. Com- 
mon. 
This is a very variable species. Sometimes very thin forms 
are found and such have been considered as species at different 
times. T'rametes rubescens Alb. & Schw. ex Fries is a thin 
form with a reddish hymenium. For illustrations, see Hard, 
Mushrooms f. 358., White, Hymen. Conn. pl. 34. f. 2., and 
Moffatt, Higher fungi of the Chicago region pl. 18. 
4. D. quercina Г. ex Fries, Syst. Myc. т: 333. 1821. 
Agaricus quercinus L. Sp. Plant. 1176. 1753. 
Plants annual, or sometimes reviving, sessile; pileus dimid- 
iate, convex, 4-12 x 4-15 x 1.5-6 em., corky, whitish to umbri- 
nous or almost black, glabrous, margin usually thick and obtuse : 
context whitish, corky, 0.2-1 em. thick; tubes 1-2 em. long, the 
mouths whitish to umber, rarely circular, more often labyrin- 
thiform and elongate or lamellate, 1 mm. or more broad, edges 
thick and entire. 
On Castanea and Quercus, sometimes on the living trees. 
Rare. 
This species is distinct from all of the others in its habitat, 
the thickness of the pileus, and the larger sinuous pores. Hard 
(Mushrooms f. 357), and White (Hymen. Conn. pL. 84. f. 1) 
give illustrations of the plant. 
LENZITES Fries, Gen. Hymen. 10. 1836. 
Pileus coriaceous to corky, dry and floccose in texture. 
Lamelle coriaceous, firm, sometimes simple and unequal, 
sometimes anastomosing behind and forming pores; trama floc- 
cose and similar to the pileus, the edge subacute. Dimidiate, 
sessile, persistent fungi growing on wood and resembling 
Dedalea. (The above description is according to Fries, Ерісг. 
Syst. Myc. 403.) 
This genus is intermediate in position between the Agarica- 
cee and the Polyporacee and is sometimes included among the 
white spored genera of the former family. 
