\C)TK ON l'(>l.)/'(>R(S LrCIDCS L1':nSS. 



511 



The mycelium of the f unions does not Hmit itself to these 

 white areas, but is present throut,diout the intervening tissues. 

 More frequently- it is hyalin and very mucli vacuolated. l)ut 

 brown and hrmer liy})h;e are also present, and show uj) \ydr- 

 ticularl}- well. 



The hyphcT are .O5-3.68 /x in diameter, less frequently 

 7.36 fx, are septate and branched, the septa often beinj^ close 

 together. Clamp connections, so common in the Polyi)oraceae, 

 are of frequent occurrence. Plate 14a shows some of the 

 hyphre from the wood of Sali.v The tii)S of the hyphal l)ranches 

 are frequently somewhat swollen. 



The wood elements of Salix have relatively large lumina. 

 The wood prosenchyma cells have lumina 11-18 fx diameter, 

 and walls 3.68 /* thick ; in the vessels' the lumina are 3*">54 /^ 

 diameter. Where vessels adjoin vessels they have bordered pits, 

 but in contact with parenchyma of the medullary rays the pits are 

 simple. The wood prosenchyma cells at times have cross walls 

 and have simple pits. The cells of the medullary rays vary ; 

 some are elongated horizontally, others transversely, whereas 

 others, again, are practically square. Their walls are i)ierced 

 by numerous simple pits. 



Unlike the maioritv of wood-destrovingf fungi, the nncelium 



^^^ 



Fig. 4. 



