51 
a greater degree than acetic, and hence as it accumulates in the liquid 
the hydrolysis of the ethyl cyanacetate is correspondingly diminished. 
It has been shown by Kastle, Johnston, and Elvove® that this grad- 
ual falling off in velocity is characteristic of the lipolytic process 
generally, and in every instance is apparently due to the same cause, 
namely, the accumulation of acid in the solution and the inhibition of 
the ferment thereby. This fact should always be taken into account 
in determining the relative stability of various esters toward lipase. 
It will be m} T object in the future to determine with greater exactness 
the proper standards for such comparisons as these herein presented, 
in the hope of being able ultimately to determine the lipolytic con- 
stant of an ester with greater accuracy. 
«Am. Chem. Jour., XXXI, 534-536. 
o 
