86 



Mycologia 



Ischnoderma fuliginosum (Scop.) Murrill 

 Sooty Ischnoderma 



Plate 7. Figure 6. X tV 



Pileus very large, subimbricate, laterally connate, effused- 

 reflexed, often covering the entire under surface of logs, the 

 reflexed portion applanate, 5-15 cm. long, 10 to many cm. broad, 

 1.-2.5 cm. thick; surface pelliculose, floccose, rugose, zonate, 

 fuliginous, ivory-black and dark fulvous, with a conspicuous 

 resinous appearance ; margin acute, concolorous, inflexed on 

 drying, entire or undulate; context fleshy, becoming corky 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 some- 

 what irregular with age, edges thin, fimbriate to lacerate ; spores 

 s'mooth, cylindrical, subcurved, hyaline, 4-6 X l -S~ 2 



This species is rather common throughout the United States 

 and Europe, occurring on stumps and fallen trunks of basswood, 

 maple, fir, spruce, and certain other trees. When young it is 

 rather fleshy, but soon becomes corky, and is always too tough 

 for food. There is no evidence that it attacks living trees, but 

 it runs rapidly over the under side df large logs, destroying the 

 wood. The accompanying illustration was made from specimens 

 growing on an old stump near the Lorillard mansion. Unfor- 

 tunately, it was necessary to reduce them very much in size. 



