POLYPOREAE OF SOUTH AFRICA. 249 



hymenophore is here lamellate and thus connects the Polyporaceae 

 with the Agaricaceae. Some of the Lenzites spp., however, show 

 the poroid character at least in the early stages. The edges of the 

 pore-months are either thick or thin and may be entire, lacerate, 

 or toothed (P. biformis, Trametes afbotexta). Extremely toothed 

 species, such as Polyporus flavus, Jungh connect the Polyporaceae 

 with the Hydnaceae. 



The hymenium. The lining inside the tubes on which the 

 spores are borne is known as the hymenium or hymenial layer. 

 Essentially this layer is composed of the spore mother cells or 

 basidia from which the spores (basidiospores) are abstricted. 

 Modified outgrowths from the pore tissue cells, which grow into 

 the hymenial layer, occur between the basidia in many species. 

 These outgrowths are of two kinds (1) colourless and either pointed 

 or inflated outgrowths known as cystidia (as in Lenzites betulina) ; 

 (2) coloured outgrowths of the nature of spines. These latter are 

 known as setae. Setae are of common occurrence in some species, 

 and this character is used for separating the species. In the 

 majority the setae are simple and sharp-pointed, rarely are they 

 bifid. In Favolus megaloporus the setae are themselves again beset 

 with spine -like outgrowths. 



These setae are generally found in the hymenium, although 

 they sometimes occur buried in the tissue of the pore-walls (e.g., 

 P. patouillardii, J', ochroporus) and even in the context tissue 

 (/''. pachyph locus) . 



The spores. The spores show the usual variations found in 

 a large group of fungi. In shape they vary from round to oblong 

 or elliptical, and may be either smooth or rough with minute pro- 

 jections. They are colourless, lightly coloured, yellowish, or some 

 shade of brown. It is unfortunate that so frequently in collections 

 of these fungi the spores are not found. Species with white or 

 light coloured context have hyaline spores, whereas in those with 

 dark coloured context the spores are either hyaline or coloured. 

 When coloured they are usually present in the specimens. One 

 type of spore found in a limited number of species herein described 

 — namely, the so-called truncate spore — requires mention. In 

 these the spores have a hyaline membrane which projects beyond 

 the base and forms an apiculum. The empty apiculum collapses, 

 and the spores at this end then have the appearance of being 

 abruptly cut off and are said to be truncate. P. ochroleucus and 

 Fomes ohiensis have hyaline truncate spores, whereas Pomes 

 applanatus, Polyporus lurid us, ]'. nigro-lucidus, and others have 

 coloured truncate spores. 



The Genera Hekein Dealt With. 



We have included in this paper the following genera: — 

 Polyporus (including Polystictus), Pomes, Trametes, Hexagona, 

 Favolus, Laschia, Lenzites, Daedal ia. 



The genus Hexagona with its usually large, subrotund or 

 hexagonal pores connects through the small pored Hexagona tenuis 

 with the genus Polyporus. The Pomes include the perennial 



