DISEASES OF TAXODIUM AND LIBOCEDRUS. 73 
would place it with the tannins. Hartig found tannin 
in decayed wood, whereas it was not present in sound 
wood, and in the present case there seems to be a similar 
instance. What the origin of the tannin may be I do not 
venture to say. 
Aside from the tannin a brown humus compound, similar 
to that found in Taxodium, occurs. It is found in the 
form of irregular granular masses which readily dis- 
solve in dilute KOH. The medullary rays in particular 
are filled with this substance (Pl. 4, fig. 2); it seems 
to permeate the cell-walls, for these turn the characteristic 
yellowish-brown color on addition of KOH, and the tra- 
cheids become filled with the brown liquid. Extractions of 
the surrounding wood with KOH yield considerable quan- 
tities of the compound. Nowhere were any dried plates 
found, such as were described for the cypress. 
MYCELIUM AND SPORES. 
The mycelium found in the diseased Libocedrus wood 
agrees so closely in appearance with that found in the 
Taxodium that the drawing on Pl. 5, fig. 1 may represent 
it as well. Few hyphae are to be found in the charred 
wood or the wood about the holes. Abundant evidence of 
their having been present is seen in the numerous holes 
which puncture the walls of the charred wood in all direc- 
tions (Pl. 4, fig. 2). No preference is shown for the 
pits. The hyphae are most abundant in wood away from 
the rotted holes. They are colorless, branch frequently 
and are provided with a large number of clamp connec- 
tions. The finest threads pass through the walls in all 
directions. Between the rotted areas the hyphae usually 
extend directly from hole to hole, just as in the Taxodium. 
In places the mycelium collects in large masses or felts; in 
these felts the hyphae are matted. Many crystals of 
calcium oxalate give the whole a white appearance. 
A brown mycelium like that found in the cypress was 
51 
