NORTHERN POLYPORES 37 



with age, very firm and rather fragile when dry, light-brown, 

 5-10 mm. thick; tubes pallid to umbrinous, 5-8 mm. long, 

 mouths minute, white, angular, equal, becoming umbrinous and 

 somewhat irregular with age, edges thin, fimbriate to lacerate; 

 spores cylindric, subcurved, 4-6 X 1.5-2 IJL. 



Frequent throughout on fallen trunks of basswood, maple, 

 fir, spruce, and certain other trees. 



25. ANTRODIA P. Karst. 



Hymenophore small, annual, epixylous, sessile or semi- 

 resupinate; surface zonate, encrusted, glabrous; context thin, 

 light-brown, fibrous; tubes short, firm, thin-walled; spores 

 smooth, hyaline. 



i. ANTRODIA MOLLIS (Sommerf.) P. Karst. 



Pileus sessile or semiresupinate, often broadly effused, the 

 reflexed portion irregular, imbricate, conchate, often plicate, 

 1-2 cm. long, 2-8 cm. broad, less than 5 mm. thick; surface 

 light-brown to umbrinous or black, encrusted, conspicuously 

 multizonate, finely tomentose to glabrous, uneven; margin acute, 

 rather thick, sterile, pale-brown, finely tomentose; context very 

 thin, membranous, light-brown next to the tubes, fulvous above 

 with a black line between ; tubes very variable in size and shape, 

 avellaneous within, 2-4 mm. long, mouths circular to sinuous, 

 1-3 to a mm., edges rather thick, firm, entire, often splitting 

 into flat teeth in old plants; spores elongate-ellipsoid, 9-11 

 X 4-5 /* 



Frequent throughout on dead deciduous wood. 



26. INONOTUS P. Karst. 



Hymenophore annual, epixylous, sessile, dimidiate, simple or 

 somewhat imbricate, variable in size; surface usually anoderm, 

 brown, hairy or glabrous; context brown, thin and fibrous to 

 spongy or corky; hymenium concolorous, usually covered with 

 whitish powder in youth, tubes small, thin-walled; spores 

 smooth, light- to dark-brown. 



Sporophore large, 10-30 cm. or more broad. 



Surface conspicuously hirsute. i. /. hirsutus. 



Surface glabrous or nearly so. 



Spores pale-brown. 2. I. dryadeus. 



Spores deep-brown. 3. /. dryophilus. 



Sporophore of medium size, about 5-10 cm. broad. 



Spores deep-brown in color; surface tomentose. 4. /. per plexus. 



Spores faintly tinged with brown; surface glabrous or sub- 

 glabrous. 5- /. radiatus. 



