108 Botany

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added to the same material and the test proceeded
with in the usual way.

In seeds the reserves are to support the seedling till
it can gather nourishment for itself. All seeds contain
protein to supply nitrogen, and either carbohydrate or
oil to supply energy. The carbohydrate, as in the pea,
bean, and all cereals, is chiefly starch, though rye
contains a good deal of sugar. In thr castor bean there
is oil instead of starch. The date endosperm is
cellulose.

In roots, the reserve is chiefly carbohydrate. The
parsnip and kumara contain both starch and sugar,
the carrot and turnip sugar only. The red beet con-
tains cane sugar, which, differing from glucose or
grape sugar, which is the form usually found in fruit
and vegetables, does not at once respond to the
Fehling's solution test. This is, as a rule, true only
of the long-rooted beet, since the turnip-rooted variety
usually contains grape, as well as cane sugar. Slice
some red beet and boil it for an hour or more in water
to which a few drops of strong sulphuric acid have
been added. Kill the acid with carbonate of soda and
then test for sugar. The usual yellow precipitate will
be obtained. The cane sugar has been changed into
invert sugar, which responds at once to the Fehling's
solution text. The dahlia root contains the carbo-
hydrate inulin, which may be precipitated with
methylated spirit, and gives a yellow colour with
iodine. In biennials, such as the parsnip, carrot, and
turnip, the reserve is accumulated in the first year, to
produce flower and fruit in the second, while in
kumara and dahlia it is to support the young shoot
which, in the spring, sprouts from the stool to form
the new season's plant.

In modified stems, such as the potato tuber and
various rhizomes and corms, starch is found in plenty.
The potato also will, as a rule, be found to contain a

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