1 6 NORTHERN POLYPORES 



Pileus more than i cm. thick, usually large. 

 Margin of pileus thick and rounded. 



Tubes large, i mm. or more across. i. S. unicolor. 



Tubes much smaller. 2. S. occidentalis. 



Margin of pileus thin, not rounded. 



Surface conspicuously hairy. 3. S. borealis. 



Surface nearly glabrous. 4. 5. delectans. 



Pileus less than I cm. thick, small or medium; surface finely 

 tomentose. 5. 5. galactinus. 



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 /*. 



Rather common on diseased living trunks of oak, maple, and 

 a few other deciduous trees from New Jersey southward and 

 westward to Missouri and Minnesota. 



2. SPONGIPELLIS OCCIDENTALIS Murrill 



Pileus thick, dimidiate, subimbricate, convex above, 5-8 

 X 7-10 X 2-3 cm.; surface conspicuously hispid-tomentose, 

 spongy, azonate, smooth or somewhat rugose, white to cremeous 

 or isabelline; margin very thick, rounded, concolorous, fertile; 

 context soft, spongy-fibrous, white to slightly yellowish, 1-2 

 cm. thick; tubes long and slender, i cm. long, white to straw- 

 colored within, fulvous in old dried specimens, mouths minute, 

 angular, 5 to a mm., edges very thin, white to cremeous, fim- 

 briate-dentate, becoming lacerate, collapsing and turning fulvous 

 in old specimens; spores ellipsoid, 4-5 X 6-7 /i. 



Occasional on beech logs in northern New York. 



3. SPONGIPELLIS BOREALIS (Fries) Pat. 



Pileus subimbricate, dimidiate to flabelliform, often narrowly 

 attached, spongy to corky, very tough, moist and juicy when 

 fresh, 5-8 X 8-12 X 2-4 cm.; surface uneven, soft and spongy, 

 hirtose- tomentose, azonate, white to yellowish ; margin thin, 

 white, entire, somewhat discolored on drying; context fibrous- 



