-t.J 



A KEY TO TllK STIPITATI-: POLVPORACKAE OF 

 TiaiPICRATl-: NORTH AMICRICA— II * 



]!V WlI.I.IAM A. MlIKKII.I, 

 E. TlIK Sl'IXMKS OK PORODISCUS 



Plant miinito, abiindaiu on twigs of chestnut, oak, etc.; stipe attached to tlie 

 vertex of the pileus and usually curved at maturity. 



P. peudiilits (Schw. ) Murrill 



F. TlIK Si'IXIES OF POLYI'ORU.S 



1. Stipe pallid or light-brown, not darker than the pileus. 2 

 Stipe wholly or partly black or fuliginous, darker than the pileus. 9 



2. Margin of pileus not ciliate. 3 

 Margin of pileus ornamented with cilia, which often disappear with age ; tubes 



alveolar. 7 



3. Pileus trumpet-shaped, deeply infundibuliform. P. craterellus B. & C. 

 Pileus not trumpet-shaped. 4 



4. Surface tomentose, often becoming glabrous. 5 

 Surface glabrous from the first. 6 



5. Tubes decurrent, very short, entire ; pileus dark-purple, with paler radiating 



lines ; known only from Alabama. P. dibaphus B. & C. 



Tubes not decidedly decurrent, denticulate when mature; pileus yellowish to 



smoky-black; common throughout. P. Polyporus (Retz) Murrill 



6. Context light-brown ; tubes decurrent ; known only from South Carolina. 



P. coluinbiemis Berk. 

 Context golden-yellow ; tubes remote ; known only from Ohio. 



P. phaeoxauthits B. & Mont. 



7. Pileus very thin, smooth, pellucid; known only from North Carolina. 



P. arcularielliis Murrill 

 Pileus opaque. 8 



8. Pileus less than i cm. in diameter, light-gray ; stipe setulose ; known only from 



Tennessee. P. arctilarifortiiis Murrill 



Pileus considerably larger, brown in color; stipe squamulose; common through- 

 out. P. arcularius (Batsch) Fr. 



9. Pileus squamose, very large, flabelliform ; tubes large, alveolar. 



P. caudicimis (Scop.) Murrill 



Pileus glabrous ; tubes punctiform. lO 



ID. Stipe ivory-black below ; pileus usually ochraceous, surface scarcely depressed, 



margin even, not becoming extremely thin. P. eles^ans (Bull.) Fr. 



Stipe smoky-black below ; pileus usually chestnut-colored, depressed at the center 



or behind, margin usually very thin and irregular. P. Jissus Berk. 



G. The Species oe AiiORTiPORi's 

 Plant rather common about stumps, usually much aborted and often only a mass of 

 pores. A. distortus (Schw.) Murrill 



* Continued from p. 30. 



