1916] 3 
ZELLER—PHYSIOLOGY OF LENZITES SAEPIARIA 491 
then duplicate portions of the collection acid were titrated 
against N/50 NaOH. Alizarin red was used as an indicator. 
Tables хп and хит show the results obtained. 
It is interesting to notice that urease is the only active 
enzyme in the fungus which produces desamidation, and that 
this enzyme was not extracted with water. Pringsheim (’08) 
has shown that the amidases of yeast do not pass out with the 
water extract but are tenaciously held by the protoplasm. The 
same may be the case with urease of Lenzites, and since we 
assume that the enzymes are protein-like bodies it is possible 
that urease in this case is not like the albumins, which are 
water-soluble. It may be a globulin, soluble in neutral saline 
solutions, or glutelin, soluble in weak alkali. 
It is again of interest here to notice that the enzyme is much 
more active in the mycelial than in the sporophoral tissue, 
even without considering the amount of sawdust present in 
the mycelial meal. Of course, here, as in other plants, it is 
not possible to connect the presence of urease with any use- 
ful function in the metabolism of the fungus. With our 
present knowledge of desamidation in plants the biological 
importance of urease remains unknown. 
HIPPURICASE 
The ability of the lower fungi to bring about the splitting 
of hippuric acid by enzyme action was first noticed by Shibata 
(204) in the case of Aspergillus niger. Some years later Dox 
(709) demonstrated the presence of hippuricase in other 
species of fungi, namely, Penicillium Camemberti, P. chryso- 
genum, and P. brevicaule, and he also confirmed Shibata’s 
results on Aspergillus niger. The enzyme preparation was 
the ground fungous mycelium after it had been dried by the 
usual “ Acetondauerhefe’’ method. His method of determin- 
ing the amount of hippuric acid hydrolyzed is given in a later 
paper (Dox, "101. After hydrolysis by the enzyme the hip- 
purie acid solution, which was made up in weak sodium 
hydroxide, was mixed with the calculated amount of sulphuric 
acid to combine with the sodium. This was shaken with 
petroleum ether which dissolves out the benzoic acid. The 
