THE POLYPOKAGEAE OF WISCONSIN. 79 



diameter, 1 cm. long, substratose, cystidia nimierous 15 to 25 microns 

 long, 6 to 10 microns thick inflated at the base; spores ferruginous, 

 globose, varying toward ovoid-globose, 3 to 3.5 microns. Context 

 suberose to coriaceous. Pores not decurrent but separated by a defi- 

 nite margin. 



In habit and context it is like Fomes igniarius. The color seems to 

 verge more toward cinnamon in some of our specimens. Specimens 

 referred to this species were collected near Madison, Blue Mounds, and 

 Ladysmith on oak and maple logs or stumps. The largest specimen is 

 15 cm. broad, 8 cm. long and 5 cm. thick. The pores change color when 

 viewed while turning the specimen in the light. 



Syn. : Pyropolyporus Everhartii (EU. & GaU.) Murr. ; 19, 30, p. 114. 

 MucroTioporus Everhartii (Ell. & GaU.) ; Journ. Myc, vol. 

 5, pp. 141—142. 



Fomes Bakeri (Murr.) (Plates VI and VII, fig. 27), 



Pileus woody, compressed-ungulate to applanate, dimidiate, slightly 

 decurrent, 4 to 10 by 8 to 20 by 3 to 5 cm. ; surface smooth, anoderm 

 becoming glabrous, 2 — 3 times deeply sulcate, isabelline to gray or 

 umbrinous; margin very broad and rounded, ferruginous, finely to- 

 mentose, perfectly smooth; context woody, dark-luteus, somewhat shin- 

 ing, 1.5 to 2 cm. thick ; tubes distinctly stratified, 5' to 7 mm. long each 

 season, avellaneous to fulvous within, mouths circular, four to 1 milli- 

 meter, edges obtuse, entire, light-yellowish to fuliginous; spores glob- 

 ose, smooth, hyaline, 5 microns. 



Common on black birch along the Wisconsin river near Kilbourn 

 and Sauk City. Perhaps it is only a form of F. Everhartii. 



Fomes igniarius (Linn.) Fries. 



Pileus at first tuberculose-globose, with a thin light covering, ap- 

 pressed-flocculose, canescent, then ungulate, blackening; the margin 

 rounded; the context zonate ferruginous; pores very small, convex, 

 fitratose, cinnamon, at maturity white-stuffed, at first canescent. 



On oak and birch. 



Very common and abundant on living oak trees at Horicon and 

 Madison. The specimens on birch come from Monroe County. The 

 largest specimen was found on birch. It measures 24 cm. wide by 18 

 cm. long and 12 cm. thick in the thickest part near the base. It has 

 four distinct sulcations and four strata of tubes — ^the oldest ones be- 



