1201 
Embryo and Alearone Layer of Hor deuni. 
capacities of isolated embryos, aleurone layers, and endosperms, and also of 
the amyloclastic generative capacity of the inner endosperm of Hordeum , by 
means of cultures of these objects on variously constituted media and sub¬ 
strata, and subsequent determination of the amounts of amylase in the 
culture medium and objects or of the products of amyloclastic action, 
shows— 
(a) Both embryos and aleurone layers possess an amylo- and a cyto- 
clastic secretory function. 
(b) These secretory functions are completely arrested and annulled 
when these objects are subjected to the action of anaesthetic 
reagents such as chloroform and nitrobenzene. This result, 
in the case of the aleurone layer, is regarded as evidence that 
this tissue possesses vitality. 
(c) The inner endosperm, under varying conditions of experiment 
described, possesses the capacity of augmenting its amylase 
content. This augmentative capacity, however, does not repre¬ 
sent a process of veritable secretion (the amyliferous cells are 
not secretory in function), and, in contradistinction to the secre¬ 
tory capacities of the embryo and aleurone layer, is not ar¬ 
rested or diminished by the action of chloroform or nitro¬ 
benzene. This latter fact, viz. the capacity of a tissue to 
augment its enzyme content as readily and to the same (or 
a greater) extent both in the presence and absence of reagents 
which are acknowledged to be fatal to living protoplasm, is 
taken to signify that (i) the inner endosperm represents amass 
of non-living tissue, and that (2) its behaviour under the con¬ 
ditions described is such as a dead mass of enzyme-contain¬ 
ing tissue would exhibit. 
2. Comparative experiments with isolated endosperms and inner 
endosperms under identical conditions of experiment, ample provision 
being afforded for the ready outward diffusion of the products of digestive 
action, show that—- 
(a) Isolated endosperms possess the capacity of inducing the complete 
auto-digestion and auto-depletion of their storage contents, 
the phenomena observed being the gradual reduction of the 
mass of the inner endosperm, the appearance of reducing carbo¬ 
hydrates in the experimental substratum, dissolution of cell 
walls and cytoplasm of the amyliferous cells, ready separation of 
the aleurone layer from the sub-aleuronic tissue, and character¬ 
istic erosive dissolution of the starch grains. 
(b) Isolated inner endosperms are incapable of inducing auto-digestive 
and auto-depletive processes in any way comparable with those 
observed in the case of endosperms, the phenomena observed 
