ii 86 Steward—Amyloclastic Secretory Capacities of the 
TABLE XXXVIII. 
Material from Air-dried Seeds : Amylase Content of Endosperms 
digested with and without Husks; of Husks and Aleurone Layers, Chilian 
Barley. Direct digestion method. 
Amylase per 20 objects per hour 
{equivalent to mg. Cu ). 
1378 
1280 
*595 
1610 
20 
2I 5 
5 objects in each experimental and control digestion. 
These results are extremely clear; the order of magnitude of the amylase 
content of endosperms 1 in Experiments 1-4 is the same, and in the barley 
in question the digestions with husks, instead of being higher, are lower than 
those without husks, a result which does not coincide with Ford and 
Guthrie’s experiments. That certain barleys may exhibit this behaviour 
is possible. The husks themselves contain but little amylase, as is 
shown by the results of Experiment 5. The aleurone layers removed by 
filing off this tissue contain approximately -|-y of that found in the entire 
endosperm. 
There appears to be a widespread idea that steeping may lead to very 
considerable reduction of the amylase content of a given barley. The funda¬ 
mental correctness of this statement is no doubt perfectly sound, but there 
is considerable probability that the influence exercised by the manner of 
steeping and the conduct of the operation on different barleys is subject to 
very wide limits of variation. Ford and Guthrie ( 1 . c., p. 67) suggest that 
the diminutions of amylolytic activity observed are due to the diffusion 
away of substances, both organic and inorganic, mainly from the husks 
during the operation. 
The results summarized in the following table are derived from 
experiments instituted for the purpose of ascertaining in what degree the 
steeping conditions indicated influence the amyloclastic content of the 
endosperm. 
1 In these and the experiments which follow, each experimental and control digestion was 
established with a definite number of objects (just as heretofore), and each object was divided 
longitudinally into its two component halves, one series of io halves serving as the experimental and 
the other io halves as the control digestion set. In this manner it was hoped that divergences 
due in the main to the individuality possessed by the objects under investigation might be in some 
measure reduced. 
1. 5 endosperms + 5 husks 
2. 5 »» +5 » 
3. 5 endosperms 
4 - 5 
5. 5 husks 
6. 5 aleurone layers 
