66 Pond.—The Incapacity of the 
solution. The only objection to Hansteen’s tests are, first: that he allowed 
the grains to soak for two days before removing the embryo, so that the 
possibility of the diffusion of enzyme from embryo to endosperm is open. 
That this is a valid objection is recognized by Brown and Escombe ('98, 
p.11). On the other hand, Pfeffer (’97, p. 612) regards Hansteen’s experi- 
ments as demonstrating the capacity of corn and barley endosperms for 
auto-depletion. Second, he does not show that the endosperm does not 
already contain some reducing sugar, which, if present, could easily diffuse 
into the surrounding water. 
Linz (96, p. 311) has shown that in isolated endosperms of maize 
under conditions of germination a marked increase in sugar content occurs 
during a period of twelve days. But since he allowed the grains to soak 
for two days before removing the embryos it is impossible to attribute this 
increase of sugar exclusively to the activity of enzymes in the endosperm. 
He draws the unqualified conclusion that the endosperm is living matter. 
A similar objection may be taken to Linz’s (96, p. 318) unwarranted 
conclusion that in such endosperms it is not the aleurone layer which 
furnishes the enzyme. He merely found that after two days’ soaking 
the aleurone layer contains less enzyme that the endosperm, which may 
mean that during the two days’ soaking enough enzyme diffused from the 
aleurone layer to establish the relative distribution he found. Brown and 
Escombe found that the aleurone layer (barley) only contains enzyme, and 
that the corrosion of starch is more notable in the tissue contiguous to it. 
Moreover, this observation disagrees with that of Griiss (98, p. 288) who 
found the aleurone layer and scutellum to contain a much greater quantity 
of enzyme than the endosperm in the case of seedlings whose hypocotyls 
had elongated six or seven centimeters. 
Leclerc du Sablon ('97, p. 395) made analyses of the date-seed 
before and after germination. He found oil and sugar to be present in the 
resting endosperm, together with some little aleurone intermixed with 
the protoplasm. The sugar is present in only about 1 per cent., and 
is to be regarded as a saccharose, since it reduces F ehling’s solution with 
precision only after boiling with acid. The carbohydrates insoluble in 
go per cent. alcohol, but soluble in water, are present in only about 2 per 
cent. Determinations of the amount of sugar present in the resting endo- 
sperm were made, and also in the endosperm during germination, when the 
radicle had elongated to various lengths. His results show a constant 
increase in the sugar content of the endosperm, but he regards the increase 
as insignificant, and concludes that the date endosperm is incapable of self- _ | 
_ digestion. Examination of his data reveals that he found O-o1g grms. 
of sugar in a quantity of endosperm tissue when the tadicle measured 
_ 050 cms., and when the radicle measured 4-0 cms. he found 0-024 grms. 
_ which is an increase of 26 per cent. Such an increase would be significant 
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. 
