SOUTHERN POLYPORES 15 



angular, sinuous at times, 4 to a mm., white to ochraceous, 

 edges thin, fimbriate-dentate ; spores cylindric, curved, 4-5 

 X 1-2 ju. 



Frequent throughout on dead branches and trunks of de- 

 ciduous trees. 



9. TYROMYCES LACTEUS (Fries) Murrill 



Pileus dimidiate, sessile, decurrent, convex, very soft, fleshy, 

 becoming rigid when dry, 2-4 X 5-8 X 0.5-1.5 cm.; surface 

 milk-white, sometimes slightly discolored, azonate, finely tomen- 

 tose or pubescent to nearly glabrous, more or less silky-striate ; 

 margin abruptly thin, inflexed, undulate, concolorous; context 

 spongy-fibrous, very fragile when dry, 5-10 mm. thick, milk- 

 white, zonate at times; tubes quite long, slender, equaling the 

 thickness of the context, 5-10 mm., milk-white within, mouths 

 regular, angular, 4-5 to a mm., glistening, becoming lacerate 

 and somewhat uneven, edges thin, dentate to sharply toothed, 

 fragile, white to slightly yellowish ; spores allantoid,4~5 X i-i .5 /* 



Frequent throughout on dead deciduous and coniferous wood. 



6. SPONGIPELLIS Pat. 



Hymenophore annual, epixylous, sessile, dimidiate, simple or 

 imbricate, rather large; surface white, anoderm, sodden and 

 bibulous; context white, duplex, spongy above, firm below; 

 hymenium concolorous, tubes thin-walled; spores smooth, 

 hyaline. 



Tubes white or slightly discolored. i. S. unicolor. 



Tubes becoming very dark colored. 2. 5. fissilis. 



i. SPONGIPELLIS UNICOLOR (Schw.) Murrill 



Pileus somewhat imbricate, large and spongy, at length 

 indurate, dimidiate, often ungulate, 5-7 X 10-15 X 3-5 cm.; 

 surface spongy-tomentose, hirtose, azonate, smooth, sordid- 

 white to isabelline or fulvous; margin very thick and rounded, 

 sterile, entire, concolorous; context spongy-fibrous, white, in- 

 durate with age, especially below, 1-2 cm. thick; tubes very 

 long, 2-3 cm., white to isabelline within, mouths large, irregular, 

 often sinuous, 1-2 mm. broad, edges thin, fimbriate-dentate to 

 slightly lacerate, white to isabelline, at length bay and resinous 

 in appearance; spores globose, 6-8 p. 



Rather common throughout most of the region on diseased 

 living trunks of oak, maple, and a few other deciduous trees. 



