1G5 



A KEY TO THE PERENNIAL POLYPORACEAE OF 

 TEMPERATE NORTH AMERICA 



By William A. Murrill 



Key to the Genera 



Hymeniuni at first concealed by a volva. A. Cryptoporus 



Hymenium free from the first. 



Surface covered with reddisli varnish, context corky. B. Ganoderma 



Surface not covered with reddish varnish, or, if so, context woody. 



Context and tubes white or pallid. C. Fomes 



Context and tubes brown or dark red. 



Hymenophore subsessile, caespitose, arising from a common trunk or 



tubercle. D. Globifomes 



Hymenophore truly sessile, dimidiate or ungulate, simple or imbricate. 

 Pileus covered with a horny crust, context punky. 



E. Elkvingia 

 Pileus not covered with a horny crust or, if encrusted, context 

 woody, ferruginous. F. Pyropolyporus 



Context dark purple or black. G. NiGROFOMES 



A. Key to the Species of Cryptoporus 



I. Pileus rounded, sessile, the volva at length perforated at one or more points; 

 found on dead trunks of conifers. C. volvatus (Peck) Shear 



B Key to the Species of Ganoderma- 



1. Context pallid to tawny. 2 

 Context umbrinous-chestnut. 4 



2. Context pallid ; plants annual, usually stipitate, growing on hemlock. 



G. Tstigae Murrill 



Context ochraceous to fulvous ; plants sessile or stipitate, growing on deciduous 



trees. 3 



3. Plants stipitate, rarely sessile, perennial ; margin of pileus truncate at maturity. 



G.jlabelliformc (Scop.) Murrill 

 Plants sessile, annual ; margin of pileus acute. G. sessile Murrill 



4. Pileus zonate, even ; tubes not stratified. G. zonatuvi Murrill 

 Pileus sulcate, azonate ; tubes stratified. G. siihattim Murrill 



C. Key to the Species of Fomes. 



1. Context white or yellowish. 2 

 Context flesh-colored, pileus flesh-colored, soon blackening. 



F. rost'HS (Alb. & Schw.) Cooke 



2. Pileus more than 3 cm. broad. 3 

 Pilous less than 3 cm. broad. 7 



