NORTHERN POLYPORES 49 



glabrous and finally nearly black with age; margin subobtuse, 

 ferruginous, velvety; context woody, fulvous, 1-2 cm. thick; 

 tubes evenly stratified, 2-3 mm. long each season, fulvous, 

 mouths circular, 3 to a mm., edges obtuse, entire, ferruginous to 

 fulvous; spores globose, compressed on one side, hyaline, 5.5-6 

 X 4.5-5 M; cystidia fulvous, ventricose, 15-20 X 7-9 M- 



Frequent throughout on diseased trunks and stumps of various 

 species of Prunus, causing decay. 



4. PYROPOLYPORUS CONCHATUS (Pers.) Murrill 



Pileus conchate, broadly effused and often entirely resupinate, 

 1-5 X 7-10 X 0.5-1.5 cm.; surface rough, tomentose, irregularly 

 sulcate, anoderm, brown to black, becoming thinly encrusted and 

 slightly rimose with age; margin acute, undulate, ferruginous to 

 fulvous, tomentose; context woody, thin, fulvous, 1-3 mm. 

 thick; tubes indistinctly stratified, 1-2 mm. long each season, 

 fulvous, mouths circular, 5-6 to a mm., edges obtuse, ferruginous 

 to fulvous; spores globose, smooth, hyaline, 4-5 /j,; cystidia dark- 

 brown, ventricose, 15-30 X 7-9 M- 



Frequent throughout on decaying deciduous trunks. 



33. FULVIFOMES Murrill, gen. nov. 



Hymenophore large, perennial, epixylous, sessile, ungulate or 

 applanate; surface sulcate, usually anoderm and often rough or 

 rimose; context woody or punky, brown, rarely dark-red; tubes 

 brown, cylindric, stratose, usually thick- walled ; spores smooth, 

 ferruginous or fulvous. 



Type species, Pyropolyporus Robiniae Murrill. 



Context fulvous. 



Pileus thick, ungulate. 



Tubes short, 1-5 mm. long each season; found only on 



Robinia. i. F. Robiniae. 



Tubes long, over 5 mm. each season; found usually on 



Quercus. 2. F. Everhartii. 



Pileus thin, conchate to applanate; found usually on Ribes. 3. F. Ribis. 

 Context reddish-brown; found only on Juniperus. 4. F. juniperinus. 



i. FULVIFOMES ROBINIAE Murrill, comb. nov. 



Pileus dimidiate, ungulate to applanate, 5-25 X 5-50 X 2-12 

 cm.; surface velvety, smooth, soon becoming very rimose and 

 roughened, fulvous to purplish-black, at length dull-black, 

 deeply and broadly concentrically sulcate; margin rounded, 

 velvety, fulvous; context hard, woody, concentrically banded, 



