112 THE POLYPORACEAE OF WISCONSIN. 



color they are paler than P. circinatus and more yellowish. The pilei 

 are very irregular, from circular to kidney-shaped. Stipe excentric or 

 lateral, thick and irregular, and attached to twigs and roots in the 

 ground. The surface is uneven and soft tomentose as is also the stipe. 



The pores are medium, irregular, shallow near the sterile margin, 

 but deeper near the center, pruinose when young. 



This species is closely related to P. circinatus but differs in the paler 

 color, the irregular pileus and the lateral stem. 



Syn. : Coltricia tomentosa (Fr.) Murr. ; 19, 31, p. 346. 

 Polyporus dualis Peck; 22, 30, p. 44. 



Polyporus circinatus Fries (Plate XIII, fig. 49.) 



Pileus circular, flat, compact, thick, zoneless, velvety, yellowish- 

 brown, composed of two layers; the lower layer continuous with the 

 stem and woody to corky, the upper soft, felt-like. Pores decurrent, 

 small, entire, grayish-brown. Stipe thick, inflated, colored like the 

 pileus, velvety. 



On the ground, under conifers. 



Not common. Localities: Star Lake, Brule river (Overton) and 

 Crandon. 



Largest specimen 8 cm. in diameter and 1.5 cm. thick. The stipe is 

 irregular, about 2 cm. long and 1 to 1.5 cm. thick. Both stipe and pileus 

 are yellowish-brown, a little paler than Polystictus perennis. The 

 small, somewhat decurrent pores are grayish-brown. 



The chief distinguishing feature is the double-layered pileus. The 

 upper layer is made of a yellowish-brown soft, felt-like substance which 

 is thicker near the somewhat depressed center. The lower layer is of 

 a brownish-wood-color, hard and corky. In general appearance it re- 

 sembles a young P. perennis, but is larger, thicker and with smaller 

 pores. 



Polyporus Schweinitzii Fries (Plate XIV, fig. 50). 



Pileus 15 to 22 cm. broad, rugged strigoso-tomentose, scrupose, dark- 

 brown with ferruginous tinge, flesh thick, spongy and soft, fibrous 

 bright brown, sometimes almost obsolete ; tubes about 6 mm. long, open- 

 ings large irregular and variable in form, yellow with tinge of green; 

 spores elliptical obliquely apiculate, pale yellow 7 to 8 by 4 microns. 



''Distinguished from P. liispidus, P. spongia, etc., by the central stem 

 which is however sometimes obsolete; it is never attached by a broad 

 lateral base." (Massee, 17, p. 231.) 



