8 
my observation. Control experiments with the boiled extract showed 
neither the oxidation of the guaiacum nor of the phenolphthalin. The 
chief point of interest connected with these observations, however, is 
that the extract of this fungus had not lost its oxidizing power at the 
end of four months. During this interval its oxidizing power was 
tested from time to time with the following results: 
Date of observa- 
tion. 
Color with guaiacum. 
Color with phenol- 
phthalin. 
Oct. 3, 1902 
Deep indigo blue 
Dark red. 
Nov. 22 , 1902 
Jan. 31, 1903 
do 
Do. 
Dark blue 
Red, 
Feb. 5', 1903 
do 
Do. 
It has also been observed that the oxidases of the Lepiota americana 
are quite stable even in the presence of alcohol and formic aldehyde. 
That such is the case may be gathered from the following observa- 
tions: On October 1, 1902, Professor Garman, of the Kentucky Agri- 
cultural Experiment Station, put up a specimen of the fungus in a pre- 
servative solution containing equal quantities of water and alcohol, 
together with 0.8 per cent of formic aldehyde. On standing in contact 
with the fungus the solution acquired a rich red-brown color. On 
December 1, 1902, some of the preservative fluid was removed from 
the specimen and tested for oxidases. It gave a splendid guaiacum 
reaction and also oxidized phenolphthalin. 
On January 31, 1903, some of this same specimen of preservative 
solution that had been removed from the fungus on December 31 was 
again tested for oxidases. It gave a slight guaiacum reaction and 
oxidized phenolphthalin slowly. It therefore showed a remarkable 
falling off in oxidizing power as compared with the aqueous extract of 
the fungus. These results go to show, therefore, that whereas most 
plant extracts lose their oxidizing properties in several days — in fact, 
often in several hours — the extract of Lepiota americana retains its 
activity for weeks and months. In this connection an observation by 
Bourquelot on the oxidases of the Russula delica is not without inter- 
est. He found that the aqueous extract of this fungus when preserved 
in chloroform first loses its power to oxidize tyrosine, then the power 
to oxidize guaiacol, and finall}", after eight weeks, the power to oxidize 
guaiacum. It would seem, therefore, that the most stable oxidases 
are those of fungi. Unfortunately the fungus, Lepiota americana , is 
rather rare in its occurrence in the locality mentioned, so that at the 
time that these first observations were made only a small amount of 
material was available for investigation. 
On the 17th of August, 1901, however, several beautiful specimens 
of the fungus were obtained. With this material some further obser- 
