PREFACE 



The chemical changes which occur in ■wood as the result of 

 fungal activity are very imperfectly understood. The records 

 of nearly all the work that has been done are in German and 

 many of them are practically inaccessible. The present pub- 

 lication is an attempt to throw some light upon the nature and 

 significance of so-called " Black Lines " or zones of decay 

 which accoinpany the activity of several species of fungi in 

 many kinds of wood. In this attempt use is made of all 

 available published work, which is analyzed and discussed 

 in the light of the observations and experiments which the 

 author himself has made. It is not claimed that the problem 

 is solved but this publication gives some new light upon the 

 subject and opens the way for continued investigation of this 

 important question. Further investigations upon this and 

 other problems of timber decay are now under way in our 

 laboratories. 



L. H. PENKIN'GTOK 



