1189 
Embryo and A leurone Layer of Hordenm . 
the structural parts of the seed induced by papain-digestions, was undertaken 
by the method of procedure already formulated. The trials showed 
definitely that a period of predigestion of the material with a 0-5 per cent, 
papain solution 1 for 20 hours at 30° C. was ample for the establishment of 
a condition of equilibrium. 
The general characters presented by the results embodied in the tabular 
statements which follow show clearly that predigestion of material derived 
from air-dried and steeped seeds (endosperms, &c.) with papain in the 
manner indicated invariably leads to a marked augmentation of its amylo- 
lytic activity or amylase content as compared with that observed when 
similarly prepared material is investigated by the direct digestion method 
employed elsewhere in this inquiry. 
TABLE XLI. 
Air-dried Dehusked Seeds: Amylase Content of Endosperms. 
Chilian barley. 0.5 % papain, 20 hours. Antiseptic, nitrobenzene. 
Exp. 
Objects. 
Amylase per 20 objects per hour 
(equivalent to mg. Cu). 
1. 
2.5 endosperms 
11050 
2. 
2*5 >> 
10800 
3 - 
2-5 » 
8693 
The results of papain-digestion of inner endosperms and aleurone layers 
from air-dried seeds are shown in the following table :— 
TABLE XLIL 
Air-dried Dehusked Seeds : Amylase Content of Inner Endosperms 
and Aleurone Layers. 
Chilian barley. 0.5 % papain, 20 hours. 
Exp. Objects . 
Antiseptic, nitrobenzene. 
Amylase per 20 objects per hour 
(equivalent to mg. Cu). 
1. 2*5 inner endosperms 6414 
2. 2*5 ,, ,, 8*03 
3* 2.5 „ „ 7752 
4. 5 aleurone-layer filings 2152 
The aleurone-layer filings represent 19 % of the total weight of 5 air-dried dehusked endosperms 
Experimental inquiry was next directed to ascertain whether the con¬ 
centration (0*5 per cent.) of papain employed in experiments so far cited 
was the most favourable, the determination being confined to the examina- 
1 The single specimen of papain used exclusively in these papain-digestions was procured from 
Messrs. Griffin, London, 
