1156 Stoward. — Amyloclastic Secretory Capacities of the 
become diffuse, then liquefaction is assumed to be either partial or complete. 
This point may be even more sharply ascertained by adding two to three 
drops of an indicator such as alizarin or phenol-phthalein, and again sharply 
inverting the tube. In those tubes in which liquefaction is incomplete the 
coloration produced by the indicator distributes itself in streaks, whereas in 
those in which complete liquefaction has taken place the distribution and 
intensity of the coloration is uniform throughout the mass. A second 
experiment with volumes of enzyme solution, chosen so as to include those 
comprehending and those lying on either side of the limits of incomplete 
and complete liquefaction indicated by the first experiment, enables the 
operator to hit off the volume of enzyme solution capable of producing 
complete liquefaction with a considerable degree of sharpness. 
After the acquisition of sufficient preliminary experience the method is 
capable of affording quite reliable comparative results. 
In the following tables are given the results of preliminary experiments 
with (1) secretions of the embryo and aleurone layers, and (2) aqueous 
extracts of endosperms, the secretions and extracts employed having equal 
saccharifying powers as ascertained by previously standardizing them by 
digestion with soluble starch. 
TABLE XXV. 
Relative Starch-liquefying and Saccharifying Powers of 
Secretions and Extracts. 
.4 % potato-starch paste. Temperature 55 0 C. 
Embryo secretion 
Volume of solution affording 
complete liquefaction. 
0.55 c.c. 
Time 
required. 
15 mins. 
Reducing power 
in mg. Cu. 
15.8 
jj j> 
o *5 jj 
16 „ 
15.0 
Aleurone-layer secretion 
°'5 jj 
9 ° j> 
116 
jj jj jj 
o -54 j> 
90 jj 
121 
jj j> jj 
o -5 j, 
9 2 jj 
118 
Endosperm aqueous extract 1 
0.52 „ 
15 jj 
13 
2 
55 JJ JJ 
°*5 j> 
15 jj 
15-7 
These results show approximately (the determination of liquefying 
power cannot be regarded as other than approximate," since the personal 
equation is invariably introduced) that when standardized solutions of 
embryo and aleurone-layer secretions prepared in the manner described, 
of equal saccharifying value with regard to soluble starch, are investigated 
as above the latter (aleurone-layer secretion) appears to possess feebler 
liquefying powers than that of embryo secretion but approximately the same 
saccharifying power. 
Similarly standardized aqueous extracts of the endosperm, which are 
virtually extracts of the aleurone-layer secretion, are practically identical 
with those of embryo secretion. 
1 From culture of distal halves of endosperms. 
2 From culture of whole endosperms, steeped as such. 
