NORTHERN POLYPORES 19 



surface milk-white, azonate, finely pubescent becoming glabrous, 

 uneven, slightly yellowish and discolored with age; margin thick, 

 usually obtuse, concolorous, entire; context white, soft, punky, 

 very juicy when fresh, with a strong fungous odor, usually 

 attacked by insects; tubes slender, 3-5 mm. long, opaque, white 

 to discolored within, mouths minute, circular to very slightly 

 angular, edges thick, entire, becoming rather thin, sordid-white 

 to umbrinous or fuliginous in dried specimens, isabelline when 

 bruised; spores globose to ovoid, 6-8 fj. long. 



Common on decayed spots in living trunks of Robinia Pseud- 

 acacia from Pennsylvania to Virginia and west to Missouri, 

 doubtless causing decay. 



2. TRAMETES SUAVEOLENS (L.) Fries 



Pileus large, subimbricate, dimidiate, convex above, plane or 

 concave below, 4-6 X 5-12 X 1-3 cm.; surface smooth, azonate, 

 finely villose-tomentose to nearly glabrous, white to pale-isa- 

 belline; margin thick, sterile, entire; context white, punky- 

 corky, 1-2 cm. thick, very fragrant when fresh, with the odor 

 of anise; tubes 5-15 mm. long, white within, mouths circular, 

 2 to a mm., edges at first very thick, white, entire, becoming 

 thinner and often blackish with age; spores oblong-ovoid, sub- 

 sinuate, 8-9 X 3-5 n. 



Frequent on willow trunks throughout, especially northward, 

 causing serious decay. Easily distinguished at some distance 

 by its agreeable odor. 



9. PIPTOPORUS P. Karst. 



Hymenophore annual, epixylous, umbonate-sessile ; surface 

 smooth, azonate, pelliculose; context white, fleshy-tough; 

 hymenium at length separating smoothly from the context; 

 tubes white, thick-walled; spores smooth, cylindric, hyaline. 



i. PIPTOPORUS SUBEROSUS (L.) Murrill 



Pileus fleshy to corky, compressed-ungulate, convex above, 

 plane below, attached by a short umbo behind, varying to bell- 

 shaped when hanging from horizontal trunks, 5-30 X 5-20 

 X 2-5 cm.; surface smoky, covered with a thin, separating 

 pellicle, glabrous, devoid of markings, cracking with age; margin 

 velvety, concolorous, obtuse, projecting beyond the hymenium 

 nearly a centimeter; context elastic, homogeneous, 3 cm. thick, 

 milk-white; tubes 0.5 cm. long, 2-3 to a mm., sodden-white, 



