The Polyporaceae of North America— XII, A synopsis of the white 



and bright-colored pileate species 



William Alphonso Murrill 



A synopsis of species with brown context was given in article 

 XI of this series. The present paper deals with the genera and 

 the principal described species having a white or bright-colored 

 context and a distinct pileus. The species of certain genera are 

 so numerous that they must form the subject of a separate article. 



Subfamily i. POLYPOREAE 



It is not always possible to draw a distinct line of cleavage in 

 this group. MicroporclliiS, for example, has sessile forms which 

 are thin and multizonate ; Funalia, while usually brown, has some 



Polyp 



Polyp. 



Hexagon 



In distinguishing the subfamilies, also, certain species of Fames 

 are annual at times, while normally annual plants may assume a 

 perennial appearance under favorable conditions. Poroid forms 

 o^Agaricus are always liable to confuse the beginner. The classifi- 

 cation here adopted is acknowledged to be imperfect and artificial, 

 but it is hoped that it will lead to something better when our 

 Knowledge of the plants treated is more complete. 



Synopsis of tbe Polyporeae witli wliite context 



Hymenophore sessile. 



Tubes hexagonal, arranged in radiating rows; context thin. I. Hfxagona. 

 Tubes alveolar; context thin, dry, surface 2onate. 2. Favolus, 



lubes mostly shallow, marginal and obsolete ; hymenium hyd- 



noid or irpiciform at a very early stage. 3- Irpiciprns. 



Tubes normally poroid, sometimes irpiciform from the rupture 

 of the dissepiments at maturity. 



Hymenium at length separating smoothly from the context, 4. Fipoforus. 



Hto 



Pileus very soft, spongy and elastic throughout. 



Hymenophore of immense size ; tubes small, 



fragile when dry. 5- Dendrophagm. 



Hymenophore small ; tubes large, not fragile. 6. Spongiporus. 



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