1180 Stoward.—Amyloclastic Secretory Capacities of the 
P . Amylase equivalent 
Xp ' to mg. Cu. 
1. 02 grm. barley + 25 c.c. 6 % soluble starch + 5 c.c. water digested 1 hour at 30° C. 316 
2. (0-2 grm. barley + 5 c.c. 0-5 % papain solution, predigested 40 hours at 30° C., then 205 
boiled) and afterwards 0.2 grm. barley + 25 c.c. 6 % soluble starch added and 
digestion continued for 1 hour at 30° C. 
3. (o»2 grm. barley + 5 c.c. 0-5 % papain solution, boiled) then predigested for 40 hours 216 
at 30°C., after which 0-2 grm. barley+ 25 c.c. 6 % soluble starch added and 
digestion continued for 1 hour at 3o°C. 
4. 5 c.c. o*5 % papain solution, boiled, and predigested for 40 hours at 30°C., after 316 
which o-2 grm. barley added and digestion continued for 1 hour at 30°C. 
The foregoing results, however, do not modify the results obtained 
in previous experiments, the retarding effect of boiled barley substance 
being still in evidence (Experiments 2 and 3). 
Finally, in view of the possible presence of substances (or bodies) 
capable of rendering the final reaction of the digestion mixture faintly 
alkaline or acid, the following digestions were carried out in presence of 
varying amounts of KH 2 P 0 4 , the barley substance being boiled before 
and after the addition of the salt in Experiment 3 and Experiments 2, 
4, 5 respectively. 
p, . Amylase equivalent 
* to mg. Cu. 
1. o-2 grm. barley + 25 c.c. 6 % starch solution + 5 c.c. water 316 
2. (5 c.c. KPI 2 P0 4 solution+ 0*2 grm. barley, boiled) +0-2 grm. barley+ 25 c.c. 6 % 221 
starch solution 
3. (5 c.c. water+ o-2 grm. barley, boiled) then phosphate added +0-2 grm. barley 211 
+ 25 c.c. 6 % starch solution 
4. (5 c.c. KH 2 P0 4 solution +0-2 grm. barley, boiled) +0-2 grm. barley 4- 25 c.c. 6 % 200 
starch solution 
5. (5 c.c. KH 2 P0 4 solution 4 0.2 grm. barley, boiled) + 0.2 grm. barley + 25 c.c. 6 % 201 
starch solution 
The final percentages of phosphate in Experiments 2, 3, 4, 5 were 0-25 %, 0.25 %, 0-5 %, and 
1 % respectively. 
The inclusion of boiled barley substance in the digestion mixture 
again leads to retardation of the same order of magnitude as in the 
preceding series of experiments. The results obtained in presence of 
varying amounts of phosphate fail to lend support to the assumption 
that the final reaction of the digestion medium may have been contribu¬ 
tory to the retardation effects observed in the earlier series of experi¬ 
ments. The possibility that the concentrations essayed were too high, it 
must be understood, is not excluded. 
The experimental evidence brought forward in the present section 
tends on the whole to negative the view that the secretions of the em¬ 
bryo and aleurone layer in any way activate the amylase of the resting 
grain. The peculiar retardative influence exercised by boiled barley sub¬ 
stance on barley amylase is a subject which calls for further investigation. 
