328 BOTANICAL GAZETTE [MAY 
one or two plants, tracing their occurrence and studying their nature 
throughout the life history of the plant. In this way it was hoped 
that some results might be obtained which would throw light on 
the nature and functions of the proteases in the life of plants. For 
this study the common field bean, Phaseolus vulgaris, which has a 
large proteid content in its seeds and shows marked vigor and rapidity 
in its growth, was selected. The work on the enzymes of Phaseolus 
has proved so absorbing that scant attention has been paid to the 
testing of various plants. The few positive results which have been 
obtained will be set down at this time. 
SPINACIA OLERACEA.—Fresh leaves of spinach were carefully 
picked over to remove all imperfect tissue and then ground up and 
the juice removed by a screw press. The residue was rubbed up 
with a little water and the fluid again pressed out. The turbid 
dark green extract was examined as follows: 
Flask no. 1—g50°¢ extract—boiled. 
Flask no. 2—s5o0°° extract—unboiled. 
Flask no. 3—50° extract +.5 8™ Witte peptone—boiled. 
Flask no. 4—50°¢ extract +.5 ®™ Witte peptone—unboiled. 
Flask no. s—so°¢ extract +.5 8™ Witte peptone +0.25 ®™ citric acid—boiled. 
Flask no. 6—50°* extract +.5£™ Witte peptone + 0.25 ®™ citric acid—unboiled. 
The antiseptic was chloroform, the length of digestion 30 hours. 
Ten cubic centimeters of each digestion were tested by acidifying 
with acetic acid, drying, taking up in alcohol and filtering off the 
residue, drying the alcoholic extract, taking up the residue in water, 
and applying the tryptophan test with chlorine water. The results 
were negative except in the case of no. 4, which showed a fair trypto- 
phan reaction. This result shows that the leaves of spinach contain 
an enzyme capable of attacking Witte peptone, but not acting on 
the proteids of the tissue, or if it does these proteids do not yield 
tryptophan on hydrolysis. 
BRASSICA OLERACEA.—The leaves of a half-matured cabbage, 
some of which were green and some etiolated, were run through 
a chopping machine and the pulp macerated with water. The 
fluid was removed by a screw press and the pale green turbid 
extract filtered. This extract was faintly acid to litmus, but not 
to lacmoid, and yielded a coagulum on boiling, the filtrate from 
