VII.] THE "DRY-ROT'^ OF TIMBER. 193 



pieces, and buried in the jar for many months or even 

 two years. 



However, I must now leave this part of the subject, 

 referring the reader to special publications for further 

 information, and pass on to a sketch of what is known 

 of other kinds of " dry-rot." It is a remarkable fact, 

 and well known, thd± Mendius lacrymans is a domestic 

 fungus, peculiar to dw^elling-houses and other build- 

 ings, and not found in the forest. We may avoid the 

 discussion as to whether or no it has ever been found 

 wild : one case, it is true, is on record on good authority, 

 but the striking peculiarity about it is that, like some 

 other organisms, this fungus has become intimately 

 associated with mankind and human dwellings, &c. 



The case is very different with the next disease- 

 producing fungus I propose to consider. It frequently 

 happens that timber w^hich has been stacked for some 

 time in the wood-yards shows red or brown streaks, 

 where the substance of the timber is softer, and in fact 

 may be " rotten " : after passing through the saw-mill 

 these streaks of bad wood seriously impair the value 

 of the planks, beams, &c., cut from the logs. 



Prof. Hartig, who has devoted much time to the in- 

 vestigation of the various forms of " dry-rot, " has 

 shown that this particular kind of red or brown streak- 

 ing is due to the ravages of Polyporus vaporarius. The 



O 



