470 



Mukrill: Polyporaceae of North America 



Pileus more or less firm, flexible or rigid. 



Context duplex, spongy above, firm below ; sur- 

 face sodden and bibulous. 7- Spongipellis. 

 Context not duplex as above. 



Pileus fleshy- tough to woody and rigid ; sur- 

 face rarely zonate. 

 Surface anoderm. 



Hymenium more or less smoke- 

 colored at maturity. 8. Bjerkandera. 

 Hymenium white or pallid. 



Context fleshy to fleshy-tough, 



friable when dry. 9. Tyromyces. 



Context punky to corky, not 



friable when dry. 10. Trametes. 



Surface pelliculose ; plants chiefly trop- 

 ical. 



Plants small, 5 cm. or less in di- 

 ameter. 1 1 • Rigidoporus. 

 Plants large, more than 5 cm. in 

 diameter. 



Hymenium flesh-colored. 12. Earliella. 



Hymenium white or pallid. 13. Cubamyces. 

 Pileus thin, leathery and more or less flexible ; 

 surface usually zonate. 



Hymenophore preceded by a cup-shaped 



sterile body. 14. Poronidulus. 



Hymenophore not as above. 



Hymenophore normally pileate ; 



tubes small and regular. 

 Hymenophore semi-resupinate 

 tubes irregular. 

 Hymenophore stipitate. 



Stipe compound. r 7- 



Stipe simple. % 



Plants fleshy, terrestrial. 18. 



Plants tough, epixylous. 



Tubes large, hexagonal and radially elongated from 



the first. I- Hexagon a. 



Tubes not as above. 



Pileus inverted, erumpent from lenticels. 19. Porodiscus. 



Pileus erect or lateral, not erumpent. 



Context duplex, spongy above, woody below. 20. Abortiporus. 

 Context homogeneous, firm. 



Surface zonate. 21. Microporelhts. 



Surface azonate. 22. Polyporus. 



I. HEXAGONA Pollini, PI. Nov. 35. pi. 2, j. 1816 

 Type : Hexagona Mori Pollini. 



Hymenophore small, annual, epixylous, flabelliform to reni- 

 form, rarely circular, stipitate, the stipe sometimes much reduced ; 



15. Coriolus. 



16. Corioleilus. 

 Grifola. 



Scutiger. 



