827 
Embryo and Aleurone Layer of Hordeum . 
Secondly, complexity is introduced into any attempt at solution of the 
question by the fact that the isolated endosperm (just as occurs when 
similarly prepared objects are investigated by the auto-digestion method) 
is capable of autonomously augmenting its amylase content. In comparable 
experiments with isolated endosperms, therefore, the augmentation of enzyme 
which invariably takes place cannot be wholly assigned to the secretory and 
excretory activity of the aleurone layer. 
Thirdly, the induction and maintenance of endospermic depletion 
processes, either in the absence or presence of the aleurone layer, demand 
the provision of conditions which must at least parallel in some measure 
those provided by the embryo, namely, ready means for the outward diffu¬ 
sion of the mobilized products of amyloclastic activity. 1 
Culture Experiments with Endosperms and Inner Endosperms 
in 5 % Gelatine with and without Mineral Salts. 
In the various experiments described in this section the sterilization, 
preparation of material, establishment and maintenance and subsequent 
examination of the culture medium and objects, &c., were carried out in 
the manner previously described. 
In the following table are shown typical examples of the relative 
augmentation capacities of endosperms and inner endosperms :— 
TABLE XII. 
Cultures of Endosperms and Inner Endosperms on 5 % Gelatine 
WITH AND WITHOUT MINERAL SALTS. 
Chilian barley. Culture period, 11 days. 
Exp. 
No. of objects on plate. 
Seeds 48 hours absolute alcohol, 48 hours water. 
Amylase per 20 objects 
Medium. (equivalent to mg. of Cu.) in :— 
Medium. 
Objects. 
Total. 
to endosperms (whole) 
Gelatine 
2474 
1190 
3664 
Gelatine-M.S. 
2634 
1349 
398 o 
10 endosperms (halved) 2 
Gelatine 
2 9*4 
1349 
4236 
10 inner endosperms (halved) 2 
Gelatine-M.S. 
1508 
39 6 
r 9°4 
2 
1239 
39 6 
1^35 
Amylase present initially in 20 
endosperms 
. 
. 
1181 
>> » if 20 
inner endosperms 
844 
We may for the present confine our attention solely to the relative 
capacities these two classes of objects, differing only by removal of the 
1 The important influence which the embryo has on endospermic depletion during the progress 
of the germinative processes can be more readily realized by the morphological changes these cells 
undergo. Their elongation lengthwise and partial separation laterally increase their absorptive 
capacity very considerably. 
Similar changes occur in the secretory epithelial cells of tea, as shown by Reed (Ann. Bot., 
xviii, 1904, p. 267). In addition deep glands are conspicuous features in the scutellum of tea, 
described by Misses Sargant and Robertson (Ann. Bot., xix, 1905, p. 115) and wholly confirmed 
by the writer’s observations. 
2 Objects halved longitudinally to facilitate diffusion processes. 
