[Vor. 5 
270 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
As in the preliminary experiments already noted, action 
on carbohydrates was determined in terms of conversion to 
glucose. In the absence of inversion processes, the Shaffer 
method adapted for plant analysis, as outlined by Davis (715), 
was used. For lipase action 10 cc. from each flask of ester 
substrate and of oil emulsion were titrated with phenolphtha- 
lein against decinormal sodium hydrate. For determining the 
conversion of amido- and amino-nitrogen into ammonia by 
the enzymes acting on acetamid and asparagin, the simple and 
rapid colorimetric method involving the use of ‘‘Permutit,’’ 
recently announced by Folin and Bell (717), was employed 
with Kober’s modified Dubose colorimeter. The action of 
proteolytic enzymes upon their respective substrates was 
noted in terms of amino-nitrogen split off, using the Van 
Slyke (712) **miero"' apparatus and 2 cc. of each substrate. 
Action upon the coagulated albumin in the digestion tubes 
could of course be estimated only in a general way because 
of the irregular masses remaining at the close of the experi- 
ment. 
For the catalase experiments the two lots of Gladiolus of 
11 corms each, already noted, were employed, after the usual 
preliminary heating to 30° C., one lot being etherized for 24 
hours at that temperature, the other serving as a control. At 
the close of the etherization period the catalase extract was 
prepared from both lots of corms by the method outlined by 
Appleman (’10). In order to eliminate a possible factor of 
error in catalase determinations caused by differences of 
time involved in preparation of two lots of extract, both lots 
of corms were, with the aid of an assistant, treated simul- 
taneously throughout all the processes of enzyme extraction. 
In a similar manner simultaneous comparison of the action of 
the two enzyme extracts upon the peroxide solution was made 
by the use of two sets of apparatus and two observers. After 
removal from the jars the corms were immediately grated to 
a fine pulp, with frequent dipping of the grated surface in 
powdered calcium carbonate to neutralize the action of any 
acids present, and quickly pressed through a tourniquet of 
several thicknesses of cheese-cloth. The resulting liquid was 
