HYMENOMYCETES 



139 



in others they may be broad and shallow. The walls or 

 dissepiments are normally thin, even so thin as to split down- 

 wards very readily in process of growth, leaving little appear- 

 ance of pores, except at the base. In some species the edges 

 of the pores are fringed and toothed, so as to resemble Irpex. 



The last group of those which constituted the old genus 

 Polyporus, contains the resupinate species, under the name of 

 Poria. The pileus is reduced to a thin stratum, mostly spread 

 over, and adhering closely to the matrix, the outer surface 

 covered with the crowded pores. In habit the resemblance is 

 to Corticium, but instead of a smooth horizontal hymenium it 

 is a porous one. Normally the pores are in a single series, 

 whilst in resupinate forms, or species, of Fomes they are thicker, 

 firmer, and stratose. 



Allied to Fomes rather than to Polystictus, the genus 

 Trametes is to be recognised chiefly by the thick obtuse 

 dissepiments of the pores, 

 the tubes deeply sunk into 

 the substance of the pileus, 

 and not stratose, and with- 

 out the hardened crust to 

 the pileus. The pores are 

 rounded and often unequal, 

 whereas in Sclerodepsis they 

 are large, sometimes an- 

 gular, with the edge acute 

 or toothed. Daedalea is 

 in substance and general 

 appearance very like 

 Trametes, with the pores 

 sinuous or labyrinthiform 

 (Fig. 53). Hexagonia rather 

 approaches Polystictus than 

 Trametes, but the pores are 

 with firm entire dissepiments. 



Fiq. 53. — Daedalea quercina. 



mostly large and hexagonal, 

 Favolus differs from Hexagonia 

 in the pores being less hexagonal, but angular and radiating 

 from the stem; most species being substipitate, and fleshy 

 rather than rigid. In Lasdhia the substance is still softer, 

 and more gelatinous, whilst the dissepiments are vein-like, 



