290 POLYPOREAE OF SOUTH AFRICA. 



1. Hexagona tenuis (Hk.) Fries. 



Pileus thin, sessile or effused reflexed, coriaceous, flexible, 

 dimidiate to conchate, or flabelliform, applanate 3-5 cm. to 7 cm. 

 by 2 cm. to 4-5 cm. by 005 cm. to 0-2 cm., often narrowly attached 

 and laterally connate; surface glabrous, concentrically zoned, 

 umber brown, smooth to rugulose, margin thin, entire to undulate 

 and rarely lobed; context rusty brown, tubes 0-5 mm. to 1 mm. 

 long, pale greyish green within; mouths hexagonal 0-5 mm. to 

 1 mm. in diam. ; edges thick, firm, entire, dark brown; spores not 

 found; hyphae 4/a diam. 



Distribution. — A widely distributed and common saprophyte. 

 Recorded by W. ITaygarth from Ngoye Forest, Zululand; on dead 

 branches of Hibiscus tiliaceus, Xanthoxylon capense, and Albizzia 

 fast if/iota around Durban, by the writer; Barberton, Transvaal, 

 by Geo. Thorncroft. 



Hexagona poly gramma, Mont ex. Fr., is too close to above to 

 be regarded as a distinct species. The pores according to the type 

 idea are somewhat larger but no larger than is found in one and 

 the same collection of II . tenuis. It is not even good as a variety. 



In specimens around Durban there was frequently noticed a 

 reddish-black stain at the base of the pileus or even extending 

 some distance over the pileus. These specimens were referred to 

 Hexagona tricolor, Fries, (or II exagona discopoda, Pat. and 

 H. umbrinella, Fr.). This stain was absent and present on speci- 

 mens of one and the same collection and would under the circum- 

 stances not be considered as constituting a specific difference. The 

 specific names may be used to convey conditions of //. tenuis, but 

 no more. 



2. Hexagona rigida, Berk. 



Pileus sessile or effused reflexed, thin and coriaceous to thicker 

 and more firm, applanate, dimidiate to conchate or flabelliform, 

 often laterally extended and connate, 3-2 cm. to 7 cm. by 1-8 cm. 

 to 4 cm. by 0-1 cm. to 1 cm.; surface concentrically zoned to 

 slightly furrowed, pale-wood coloured to fawn, smooth or rugulose; 

 margin thick or thin, entire to undulate; context 005 mm. to 

 9 mm., fibrous, corky, white to lightly coloured; tubes 2 mm. or 

 less long, white to fawn within, mouths circular to hexagonal, 

 0-5 mm. to 1 mm. in diam.; edges thick, white to yellow or fawn; 

 hyphae 4/x to 5-5/x. 



Distribution. — Not uncommon around Durban, by the writer, 

 and varying considerably in thickness. Some collections also had 

 the reddish-brown stain mentioned under //. tenuis. 



The plant differs from H. tenuis by lighter colour of context. 



A specimen collected at Victoria Falls by Miss A. V. Duthie, 

 of the University of Stellenbosch, and referred to Hexagona 

 phaephora, Pat., differs from above in somewhat darker pores, but 

 no more than one finds in collections of II . rigida, and is referred 

 here. 



