1148 3 toward,—Amytoclastic Secretory Capacities of the 
under partial anaerobic conditions, with simultaneous partial removal of 
the aleurone layer itself. 
In the following experiments the dorsal portion of the layer was 
completely removed before the establishment of the cultures. The objects 
(Experiment 1) were cultivated in the customary manner under aerobic 
conditions; in the remaining numbers of the series, under anaerobic condi¬ 
tions, the objects were embedded in the lowest part of a column of agar 
medium, having a uniform depth of 10 cm., and contained in test-tubes, the 
mouths of which were.closed with loosely fitting cotton-wool plugs. 
TABLE XXL 
Cultures of Endosperms deprived of the Dorsal Portion 
of their Aleurone Layers on o-8 % Agar, with and 
without Mineral Salts. 
Chilian barley. Seeds, 48 hours absolute alcohol, 48 hours water. Culture period, 68 days. 
Exp. Objects. Culture medium. 
1. 10 endosperms deprived of o*8 % agar-mineral 
dorsal aleurone layer (whole) salts 
2. 10 endosperms deprived of o»8 % agar-mineral 
dorsal aleurone layer (halved) 3 salts 
3. 10 endosperms deprived of 08% agar-mineral 
dorsal aleurone layer (halved) 3 salts 
4. 10 endosperms deprived of o«8 % agar 
dorsal aleurone layer (halved) 3 
5. 10 endosperms deprived of o*8 % agar 
dorsal aleurone layer (halved) 3 
Amylase per 20 Reducing 
Conditions of objects. sugars in 
experiment. Direct . 1 Papain} medium? 
(equivalent to mg. of Cu.) 
aerobic 
■— 
anaerobic 
168 
anaerobic 
168 
anaerobic 
168 
anaerobic 
337 
— 
432 
4220 
216 
4810 
89 
2194 
T 34 
3544 
113 
In Experiment 1 at its termination there remained in the majority of instances the ventral 
portion of the aleurone layer only, the starch contents and cell-structures of the inner endosperm 
having almost completely disappeared. 
Those in which a starchy residue of inner endosperm still persisted showed on microscopical 
examination the phenomena customarily presented by endosperms undergoing digestion, namely, 
deeply and extensively eroded starch grains, and totally disorganized and disintegrated cell-walls 
and cytoplasmic debris. 
On desiccation for a few hours at 30° C. the resistant aleurone-layer tissue only remained, and 
therefore no estimation of its amylolytic activity was undertaken. 
This experiment is of interest because it shows distinctly that the 
ventral portion of the aleurone layer resembles the dorsal portion (provided 
the experiment is sufficiently prolonged) in possessing an intense power of 
depleting the inner endosperm. But unquestionably, during both natural 
germination and under the artificial conditions described in these experi¬ 
ments, the secretory function of the aleurone layer appears to be more 
1 Amylase in objects determined by direct and papain digestion methods. 
2 Reducing sugars in medium estimated directly. 
3 Objects in Experiments 2-5 halved longitudinally to increase extent of diffusion surface. 
