,12 



NOTE ON POLYPORUS LUCWUS LEVSS. 



of P. lucid US has not been observed to bore directly through 

 the cell walls. In 'lx)th the wood prosenchyma and medullary 

 rays (Figs. 2 and 4) the hyphge invariably pass through the pits, 

 and in this process often appear to become somewhat con- 

 stricted. 



To stain the hyalin hyphge I employed methyl violet after 

 first mordanting the sections in tannic acid. With this stain 

 the pits usually showed up particularly well, l)Ut the wood ele- 

 ments only took it slightly. 



In the deca}ing wood it was noticed that starch was absent 

 ifrom the medullary rays, and since this substance is easily di- 

 gested, it is probably the first to be utilised by the ftuigus for 

 its nourishment. 



The action of the fungus on the wood can be described as 

 one of digestion. Schulze's solution (chloro-iodide of zinc) 

 clearly shows that the fungus causes the delignification from the 

 walls bordering the lumina, and is foll<nved bv the digestion of 



Fig. G 



