1916] 
ZELLER—PHYSIOLOGY OF LENZITES SAEPIARIA 501 
OXIDASE AND CATALASE 
Interest was first aroused concerning oxidases in higher 
fungi because of the discoloration of certain fungous tissues 
when exposed to the air. During the years 1895, '96, and '97 
many papers appeared by Bourquelot, Bertrand, Hérissey, et 
al., dealing with the oxidases in the higher fungi. They found 
that laccase was widely distributed in the Basidiomycetes, and 
in the case of Boletus cyanescens, the bluing of injured spots 
was due to the laccase acting with the oxygen of the air on 
the boletol present in the tissues. 
Bertrand (’96) showed that the crystalline chromogen in 
Russula, especially Russula nigricans, was tyrosin, and in the 
latter the tyrosin on exposure to the air was oxidized to 
melanin, a black substance. Tyrosinase in the tissues oxidized 
the tyrosin, causing the tissues to blacken. 
Lutz (712), investigating the oxidases in the stipes and pilei 
of Gyromitra gigas and Disciotis perlata, found tyrosinase 
present in both species, but in both a more marked action in 
the eaps than in the stipes. Euler ('08) carefully investigated 
the catalase of Boletus scaber. There seemed to be a rela- 
tion between the oil content of the fungus and the amount of 
catalase present, and the presence of a metal, like magnesium 
hydroxide, in the solution increased the catalytic action. 
The literature concerning the function of oxidases in plants 
has been amply considered by Clark (711), who makes special 
mention of the relation of oxidases to chromogens in the 
higher fungi and their possible aid in the respiration process. 
In my experimental work on oxidases and catalase no quan- 
titative determinations were made. In some instances the 
enzyme dispersions were used, in others the fresh tissues. 
Clark's (710) methods were used, and guaiacum, alpha- 
naphthol, and paraphenylenediamine were used as indicators 
of oxidation. The mycelial extract was made from pure cul- 
tures of L. saepiaria grown on Thaxter's potato-hard agar. 
Ten grams of fresh fungous mat were ground with sand and 
treated with 100 cc. of distilled water. This extract (5 drops 
in 5 се. of H202) caused a rapid evolution of gas, showing the 
presence of catalase. The sporophoral meal showed much 
