POLYl'ORt-. 435 



side is concentrically marked, ami ha< a stone-hard coating which 

 is generally more or less cracked; several /ones and layer- l 

 tubes will be found when the sporophore is cut in section. 



This fungus produces a white-rot in tin- wood. and is one of the 

 most common and dangerous of wound-parasites. Tin- \\ ..... I 

 attacked by the mycelium is at first dark in colour, then 

 yellowish-white and soft. According to Harti-. a delicate 

 mycc.liuni tills up the elements and eats away the inner layers 

 of the walls: then the middle lamellar are transformed into 

 cellulose and absorbed by it i Fi-. L'o'4). 



Polyporus fomentarius (L.) (/b ///..> fomentariiis iL.) Fr. 

 (I'.ritain and I'.S. America). "Tinder-fungus." Sporophoiv- 

 broad and shaped like reversed brackets or hoofs. Their up]"-! 

 side, at first brownish and velvety, becomes afterward- smooth. 

 uivy, and marked with broad concentric /.ones. The mar-in 

 is rounded and uniformly grey. The pore-layer is smooth and 

 greyish-brown. A longitudinal section >ho\v> a homo^-mms 

 tinder-like mass, covered on its lowei- suiface h\ layer- or 

 xones of pores. 



The tiiidei-fmiu'us is parasitic on beech, dm. and mountain 

 maple. It is particularly common in beech-forests, and v. 



11 more SO at olle time whell the infeetcd tree- \\ere allowed 



to remain standing. The sporophoie- may be found on li\inu 

 Stems, "ii remnants of trees broken by wind, and mi felled 



tl'ee-. For some distance above alld beloW the >eat of the 



sporophoie runs a furrow on the stem, marking a traet when- 

 the myeeliiim ha- jieiietrated to the cambium and killed it, 80 

 that 'jrov/th in thickm- ceases < FL'. 266, a). 



The mycelium causes in the W<MH| a white-mi of a li-ht 



V.'H,,U colour. Where the Wood J- still til'lll, llloll^ll dlMM-i'd. 



it will he found to be divided into cubical poition^ by \\hite 

 tiaet- of myeeliiim which run both radially and \ei;icallv. A 

 \ery chuacteii-tic feature <>f the dc-i ruction con-i-t- of broad 

 white leathery bainh of mycelium, formed in a radial direction 



throll'dl the \\ood: llie-e are lie-t -cell oil -telllS -liattcled b\ 



' i m, or on 



!: i ' p. , urg, l^ > .'!. TnlM-ui. M ' iln-iliiii. 



/' ' . ". ,/'i./J / 1^7. A c ....... i"" ! 



-' Knill (& ,/aii'l, Kvll . I ^'.L'!' 'li-i ii' ' ll 



.Ul'i MUM. 



