DISEASES OF TAXODIUM AND LIBOCEDRUS. 37 
usually more numerous at the lower end of the cells. When 
KOH is added the whole mass dissolves slowly, melt- 
ing away like wax; the tracheids become filled with the 
red-brown solution. By treating finely divided wood with 
dilute KOH this substance can be extracted in quantity. 
If the potash solution is neutralized with dilute HCl, a red- 
brown flocculent gelatinous precipitate is formed slowly, 
which gradually settles to the bottom. When dried it re- 
sumes the appearance seen in the tracheids. In mass it is 
reddish-brown, soft, tasteless and odorless, insoluble in 
alcohol, ether, chloroform, acetone, turpentine, etc., but 
very soluble in alkalies, KOH, NaHPOg, ete., and can be 
reprecipitated from such solutions by acids. Because of 
its peculiar physical and chemical properties the sub- 
stance is classed among the humus compounds. This 
humus compound, as it will be designated, was evi- 
dently at first in a liquid condition, as it fills the cells 
so evenly. Furthermore, wherever mycelium occurs, 
this is coated with a layer of the compound, so that 
the walls of the hyphae look brown and show several con- 
tour-lines. Wherever there is any sign of decomposition, 
there this product appears immediately. It is at first seen 
in the medullary rays, filling the cells and obscuring their 
contents so that nothing can be distinguished in the cells. 
The brown contents of the rays extend out through many 
annual rings from the initial point of decay. On several 
occasions trees were found with exceptionally large quan- 
tities of this material. In these trees the cavities or holes 
had a brown powdery mass lying loosely within, but the 
bounding walls had athick coating of the brown substance. 
It was quite soft, broke readily with a shining fracture, was 
non-elastic and dissolved readily in alkalies, in fact agreed 
so closely with substance already found in the tracheids as 
to leave no doubt as to their being one and the same sub- 
stance. The finding was of value as it was possible to 
trace the origin of this compound directly, which was not 
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