1916] 
ZELLER—PHYSIOLOGY OF LENZITES SAEPIARIA 483 
No work on wood-destroying forms has demonstrated the 
presence of an enzyme capable of disorganizing the middle 
lamellae, although many of the decays show maceration. 
Spaulding (711) says that in the last stages of decay рго- 
duced by Lenzites saepiaria the middle lamellae have disap- 
peared. 
Since it was found in microchemical observations that the 
middle lamellae of the wood decayed by L. saepiaria were dis- 
solved out, it was attempted to demonstrate pectase and pecti- 
hase experimentally. Pectin was prepared in the usual way 
by the action of alcohol on the juice expressed from cran- 
berries. Pectase from the carrot coagulated this pectin, but 
only negative results were obtained with the enzyme disper- 
sions from L. saepiaria. Further experiments were con- 
ducted to determine the macerating power of the dispersions 
on various tissues. 
Slices of carrot, potato, and beet were cut to a uniform 
thickness. From these slices dises were cut by means of a 
cork-borer, and similar discs were also prepared from very 
young tobacco leaves. As a source of enzymes, the mycelial 
powder prepared from mycelium grown on carrot juice was 
used. Two grams of this powder were soaked in 50 сс. of 
distilled water for 5 hours, after which the liquid was 
deeanted off. 'The four kinds of dises mentioned above were 
placed in portions of this liquid in closed stenders and a few 
drops of toluol added to each. Dises were also kept in dis- 
tilled water as controls. Observations were made after 18 
hours. Carrot discs in the mycelial extract had lost in coher- 
ence in comparison with those in the distilled water. When 
pulled apart the latter were torn as much across the cells as 
following the cell walls, while in the former the separation fol- 
lowed the line of the cell walls. Beet dises showed no macera- 
tion whatever after 18 hours. Potato dises showed a more 
marked maceration than the carrot. The potato had become 
very flaccid in the extract. The discs of tobacco leaves 
showed no loss of coherence. After 42 hours the carrot discs 
and potato discs had lost all coherence, and the cells were 
easily pressed apart under a cover glass. In the controls in 
