832 Steward.—Amyloclastic Secretory Capacities of the 
these conditions entails enzyme destruction; only by prolongation of the 
experiment can this feature be rendered apparent, because during earlier 
phases of the culture experiment enzyme elaboration probably overshadows 
the opposed processes of enzyme inactivation and destruction. During 
normal germination within the limits of the malting period the accumulation 
of amyloclastic and other enzymes must necessarily be greatly in excess 
of the demand in order to ensure finally a substantial amount of residual 
enzyme. 
These experimental results afforded by cultures of inner endosperms 
and endosperms on gelatine mineral salt medium may be briefly sum¬ 
marized. 
Both types of experimental objects possess the capacity of augmenting 
their amylase-content, the capacity of the endosperm, by virtue of exercise of 
the secretory functions of the aleurone layer, being distinctly superior to that 
of the inner endosperm. 
These experiments therefore furnish indirect collateral confirmation 
of the results already afforded by independent investigation of the isolated 
aleurone layer. 
The secretion of amylase in the endosperm culture experiments is, 
if the experiment is of sufficient duration, invariably accompanied by the 
appearance of reducing sugars in the culture medium in easily demonstrable 
amounts. 
In the inner endosperm experiments on this medium, this phenomenon 
is either absent or barely demonstrable, the amount of amylolytic action 
being minimal. 
Macroscopically and microscopically the two series of objects, i. e. 
endosperms and inner endosperms, at the termination of the culture 
experiment, present features which are in marked contrast to each other. 
There is invariably, in the case of the endosperm, reduction in the 
mass of culture objects, marked erosion of starch grains, and considerable 
alteration in the cell-walls of the amyliferous cells, features which are 
entirely absent in the inner endosperm cultivated and examined under 
identical conditions. The mass of the inner endosperm in these latter 
experiments remains practically unchanged, and there is an entire absence 
of any visible or readily recognizable change in either the starch contents or 
the cell-walls of the storage tissue. 
Since in the one case the aleurone layer remains, and in the other it is 
removed, and further since direct experiment demonstrates that the aleurone 
layer possesses the capacity of secreting an active variety of amylase, it 
is difficult to avoid the conclusion that the observed phenomena are pri¬ 
marily due to the amylase which arises as a product of the secretory activity 
of the aleurone layer cells. 
