Fam. 2. POLYPORACEAE. 



A. Fleshy, putrescent. 



Stem central ; tubes long, in a layer easily separable from the rest 

 of the pileus ....... Boletus 



Stem central ; tubes in a layer less easily separable from the rest of 

 the pileus than in Boletus ; pileus and stem highly squarrose- 

 squamose ........ Strobilomyces 



Stem central ; tubes arranged in radiating rows in a layer less 

 easily separable from the rest of the pileus than in Boletus 



Boletinus 



Stem lateral or wanting ; tubes distinct from one another but 

 crow'ded together, at first resembling minute warts Fistubna 



B. Coriaceous, horny, or woody, or fleshy in some species of Poly- 

 porus but becoming rather dry with age. 



Tubes in a layer distinct from the substance of the pileus but not 

 separable from it, tube-like from the first, not stratose ; pileus 

 fleshy or tough but not woody ; stipitate or sessile Polyporus 



Tubes as in Polyporus but usually stratose ; pileus woody from the 

 first, sessile . . . ... . . . Fomes 



Tubes as in Polyporus, not stratose, developing from the center 

 gradually outward towards the margin of the pileus, at first 

 punctiform and gradually becoming tube-like ; pileus coriaceous 

 or membranaceous ...... Polysticus 



Tubes as in Polyporus or Polystictus, not stratose ; fructification 

 resupinate, effused, with no true pileus, waxy, coriaceous, or 

 membranaceous ....... Porta 



Tubes extending to unequal depths into the substance of the pileus 

 and not forming a distinct layer, sub-cylindrical, not stratose ; 

 fructification corky, sessile or resupinate . . Tranietes 



Tubes as in Trametes but sinuous-labyrinthiform in cross section ; 

 fructification corky, sessile .... Daedalea 



Tubes replaced wholly or in part by concentrically arranged lamellae ; 

 pileus coriaceous, with or without a central stem Cyclomyces 



Tubes alveolar, arranged in series radiating from the stem, shallow, 

 broad, and apparently formed by anastomosing lamellae ; pileus 

 fleshy-tough, dimidiate ...... Favolus 



Tubes as in Polyporus but forming a gelatinous layer : fructification 

 dimidiate or effuso-reflexed in our single species Gloeoporus 



