840 Stoward.—Amyloclastic Secretory Capacities of the 
endosperm is restricted to the immature starch granules of minute size, 
which are always present in all parts of this tissue. 
Invariably, in endosperm experiments such as Experiment 1, not only 
are the starch reserves degraded, but there is overwhelming evidence of 
advanced cytoclastic action. The cell-walls of the amyliferous cells exhibit 
every gradation of disintegrative change, from the initial swelling up and 
splitting into laminae to their complete dissolution. Careful, often repeated, 
examination of the cell-walls of objects ‘cultivated’ as in Experiments 
2 and 3 fails to afford any conclusive evidence of cell-wall disintegra¬ 
tion. Thin sections of such objects, treated with diluted saliva at 30° C. 
for several hours in order to dissolve out their starch contents, do not 
exhibit any recognizable sign of having undergone even partial cyto- 
hydrolysis. 
Physical examination of endosperms and inner endosperms removed 
after periods (varying from 7 to 20 days) of cultivation on calcium sulphate 
and subsequent desiccation for 24 hours at 30° C. shows that, while the 
former objects are distinctly friable, the latter do not exhibit this attribute, 
and the almost unavoidable inference to be derived from these observations 
is that cytohydrolysis of the cell-walls, even where it does not result in their 
complete disintegration, is correlated in some way with acquisition of 
friability by the endospermic contents. 
Finally, examination of the action, either of these two types of objects 
directly or of aqueous extracts prepared from them, on gelatinized starch 
affords a further means of emphasizing points of difference in the attributes 
of the amyloclastic enzymes, which take their origin in the aleurone layer 
and inner endosperm respectively. 
The objection may be raised that the method of preparing inner endo¬ 
sperms in Experiment 2 does not preclude, on the one hand, possible 
coagulation of amyloclastic enzyme by absolute alcohol; on the other, 
considerable loss of enzyme by aqueous extraction during the steeping in 
water. 
This objection is partly met by the results of Experiment 3, in which, 
by the method of steeping adopted, the inner endosperm was not exposed to 
these influences. In order to dispel this objection, inner endosperms were 
prepared as described in Experiment 2, and determinations were made of 
the amount of amylase which had diffused into the steep-water during 
steeping, and of the amylase present in the objects immediately after 
removal from the steep and subsequent desiccation at 30° for 24 hours. 
The results were :— 
Amylase per 20 per hour 
(equivalent to mg. of Cu). 
Amylase in steep water ...... 261 
Amylase in inner endosperms (direct digestion) . . 1055 
Amylase in inner endosperms (0.5 % papain digestion) 2966 
