1919] 



SCHMITZ STUDIES IN THE DECAY OF WOOD 95 





reason their results are far less valuable and can in no way 

 be taken as general. It has been shown by von Schrenk ( '00) 

 that even on the same kind of wood two fungi may act in an 

 entirely different manner with respect to which portion of 

 the woody tissue is utilized. Thus, Polyporus juniperinus 

 growing on the wood of Juniperus virginicma caused a de- 

 lignification in the first stages of decay and the remaining 

 wood fiber was completely reduced to cellulose. Polyporus 

 carneus, on the other hand, almost entirely removed the cellu- 

 lose when growing on the same wood. 



Spaulding ( '06) differs to some extent from the 

 pressed by Potter. Steaming tests were made with a variety 

 of woods, thin sections being placed in the Arnold sterilizer 

 or the autoclave and the effects noted by micro-chemical reac- 

 tions. Spaulding obtained slight delignification in Sassafras 

 Sassafras after fifteen hours of boiling, and in Picea rubens 

 after seven hours in the autoclave or with interrupted boiling 

 after a total of twenty-seven hours. With these two excep- 

 tions forty hours of boiling seemed to have no effect upon the 

 lignin of the sections. In other tests, using the autoclave at 

 a temperature of about 120° C, it was found that many woods 

 gave evidences of delignification after fifteen hours of treat- 

 ment, and nearly all after eighteen hours. 



Spaulding, however, does not consider these effects impor- 

 tant with reference to experimental work with the wood-de- 

 caying fungi, since it is claimed even the very thin sections 

 had to be subjected to the action of boiling water for relatively 

 long intervals before any decided effect could be detected. 

 In discussing the effects of boiling water on finely divided 

 wood, however, he admits that lignin is extracted in sufficient 

 quantity for lignin reactions to be obtained in the filtrate 

 from the extracted material. The effect of autoclaving thin 

 shavings for one hour was also tested by Zeller ( '17). It was 

 found that the sections were not delignified to such an extent 

 that by staining with zinc chloriodid any change could be de- 

 tected, although the water in which the shavings had been 

 boiled gave a very faint pink color with phloroglucin and hy- 

 drochloric acid. 



