154 The Journal of Heredity 
and may afford means of distinguishing 
some of the varieties. 
The function of this cotyledon is to 
absorb the endosperm and carry the 
food material over to nourish the grow- 
ing parts of the young seedling. In 
order to be absorbed, the food materials 
stored in the endosperm have to be 
digested, and the digestion is accom- 
plished by ferments secreted by the 
cotyledon, as in the familiar change of 
starch into sugar in the malting of 
barley and other grains, preceding the 
formation of alcohol. 
THE COCONUT’S STOMACH 
The digestion of the endosperm is 
evidently more rapid at the places 
where it is in contact with the coty- 
ledon. The softening of the surface 
elsewhere (see Fig. 5) may mean that 
the milk of the germinating nut be- 
comes charged with a digestive ferment 
secreted by the cotyledon. Hence it 
may be considered that the fluid-filled 
cavity of the germinating nut, in addi- 
tion to its storage function, serves like 
a stomach, to provide for a more rapid 
digestion and absorption of the stored 
food materials than would be possible 
by the direct action of the cotyledon. 
It is easy to understand that such a 
system might be very useful to the 
young plant in enabling it to make more 
rapid growth in short periods of favor- 
able conditions. If this view is correct, 
we may think of the milk as being 
recharged with food materials from the 
endosperm, to replace those that are 
absorbed by the cotyledon. 
That sugar is present in the cotyledon 
is evident from the sweet taste of the 
latter, and the very delicate texture 
suggesting sponge cake is altogether 
different from the hard oily ‘‘meat”’ of 
the nut. These enlarged cotyledons of 
the germinating nuts are considered 
luxuries and food for invalids by the 
natives of the Polynesian Islands and 
other parts of the tropics. In the 
native markets of towns along the 
west coast of Mexico the dried coty- 
ledons are sold under the name of 
‘““manzanas de coco”’ or coconut apples. 
(See Fig. 6b.) 
OTHER INTERNAL CHANGES 
More detailed studies of what takes 
place inside the germinating coconut 
have shown interesting changes in the 
composition of the food materials. 
Thus Walker,? in his experiments with 
a selected series of nuts* in the Philip- 
pines, found that the total quantity of 
milk shows a marked diminution from 
374 grams in an unsprouted nut to 
nothing when the sprouts had attained 
a height of 93 centimeters. A decided 
loss in the sugar content of the milk 
took place at the same time, falling 
from 2.3 per cent in the milk from the 
unsprouted nuts to 0.3 per cent in the 
ones which had sprouts 38 centimeters 
long. 
A decided loss in the total weight of 
the meat was also evident, as it dropped 
from 457 grams in the unsprouted nut 
to 148 grams in the nut with a sprout 
93 centimeters long. The loss seemed 
to be due to a direct absorption by the 
cotyledon, the process taking place only 
in that portion of the meat located near 
the latter, but increasing rapidly as the 
cotyledon grows larger and comes in 
contact with the entire surface of the 
endosperm. This would be the case, 
necessarily, if the nuts failed to main- 
tain a supply of liquid in the cavity. 
The loss in the total weight of oil was 
fairly proportional to the loss in the 
total weight of meat. During the early 
stages of germination there appeared to 
be a concentration of oil near the coty- 
ledon, with a corresponding loss in that 
portion of the meat farthest away. 
The percentage of sugar decreased from 
4.1 per cent in the unsprouted nut to 
1.2 per cent in the nut with the longest 
sprout (93 centimeters.) The loss ap- 
peared to be due to the absorption of sugar 
by the foot, as in all cases less sugar was 
found in that portion of the nut in direct 
contact with the cotyledon than in the 
parts farthest away from the cotyledon. 
2 Philippine Journal of Science, Vol. III, June, 1908. : 
‘ Four pairs of coconuts of different ages but approximately of the same size were selected 
for this work by Dr. Walker. 
all to nuts with a sprout 93 centimeters long. 
The range in the age was from nuts which had not sprouted at 
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