462 



BASIDIOMYCETES. 



scales arranged regulnrly in concentric lines. The stools break 

 out from living stems through cracks in the bark or from wounds, 

 r.//. those made by wood-peckers. 



The fir-wood, normally white, assumes, 

 when diseased, a yellow or honey-colour, 

 more or less like the sporophore, while 

 here and there, parts may become light 

 brown. The hyphae grow in all direc- 

 tions, but especially as white strands up 

 and down the year-rings, while others 

 in horizontal and vertical direction break 

 up the wood into irregular patches 

 (Fig. 290). * In the final stages of 

 destruction the wood will be found 

 A laminated into its separate year-rings 



%. and very much broken up into irregular 



\ pieces (Fig. 291). 



I' , The sporophores of this Afjaricus are 



not uncommon protruding from l)ark- 

 cankers caused by Aecidium clafinvm, 

 and its mycelium assists in the destruc- 

 tion of the stem. 



W." 



'^■H^'i 



FlO. 292. — Agaricus adiposiis 

 and Polyporum Hdrtigii. Destruc- 

 tion of Fir- wood. The boundary 

 of the regions affected by the 

 two fungi is formed by a verj- 

 dark line of demarkatiou. To 

 the right the destruction is that 

 produced by Pobjporov.s Hartigii, 

 to the left by AgarirvK n.dipoxv^. 

 (v. Tubeuf phot.) 



Agaricus (Pholiota) squarrosus (INIiill.). On 

 living and deail stems of broad-leaved trees. 

 (Britain.) 



Ag. (Ph.) destruens (Brond.). On living 

 and dead steins of poplar. (Britain.) 

 Ag. (Ph.) aurivellus (Batsch.). On living and dead stems of broad-leaved 

 trees. (Britain.) 



" FUNGI IMPEEFECTI." 



The fungi placed here have life-histories which as yet Iiave 

 not been completely investigated, most of them being known 

 only in the form of pycnidia or conidia. The number of species 

 was at one time much larger, but it is gradually being re- 

 duced as the forms are proved to be stages in the life 

 of some species of definite systematic position in the other 

 groups already considered. 



The group may be divided into the provisional sub-groups, 

 the Sphacropsidcae, Mclanconieae, and Hyphomycctes. 



