nrHENOMYCETES. 



Genus ^2. MERULIUS, Haller. 20 Species. Fries Ep. 



Hymenophorc sub-floccose ; pores incomplete, sometimes mere 

 sliuUow cavities or sinuous depressions. Epixylous. 



Genus 23. POROTHELIUM, Fries. 4 Species. Fries Ep. 



Ecsupinate, expanded ; substance woven from the mycelium ; 

 sub-membrauaceous, with projecting papilla;, which arc distinct 

 fi-om the first, soon open pore- wise, at length elongated, tubular. 



Genus 24. FISTULINA, BuUiard. 2 Species. Fries Ep. 



Pileus fleshy ; tubes at first wart-like, closed, at length open. 

 Epixylous. 



Synopsis of POLYPORUS. 



Suh-Genus MESOPUS. 



Pileus entire ; stem simple, central ; base of the same colour. 



Sub-Genus TLEUROPUS. 



Pileus tough or corky, horizontal, not ciroinate ; stem simple, 

 ascending, corticated, either distinctly lateral, or cxceutric 

 with a black base. Arboreal or epixylous. 



Sub-Genus MEPJSMA. 



Stem compound, arising from a common tubercle or base, 

 extremities bearing numerous pileoli. 



Sub-Genus APUS. 



Pileus sessile, properly adnate and dimidiate, with a thickened 

 and dilated base; or entire, attached by an umbo ; or attenuated 

 at the base ; or sometimes, but not normally, wholly resu- 

 pinate. 



I. ANODEIUIEI. 



Pileus ntfl covered by a cuticle, lioueless ; annual. 



II. PLAC0DEB3IEI. 



Pileus becoming hard, covered with a close crust, zoncless or 

 concentrically grooved. Persistent. 



HI. INODEItMEI. 



Pilous from the first dry and firm, covered with a thin fibrous 

 cuticle. 



Sub-Genus KESUPINATUS. 



I'ileus none ; jorcs springing from the uiyccliuui wilhuut any 

 ill! t.ivcniiig .substance. 



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