aking. Removing the seed-covering, we find the greater part of the seed
to be albumen. Closely applied to one side of this, so closely that it
is difficult to separate it perfectly, is the single cotyledon. This
completely surrounds the plumule and furnishes it with food from the
albumen. There is a line down the middle, and, if we carefully bend back
the edges of the cotyledon, it splits along this line, showing the
plumule and caulicle within. The plumule consists of successive layers of
rudimentary leaves, the outer enclosing the rest (Fig. 10, 1, _c_). The
latter is the first leaf and remains undeveloped as a scaly sheath (Fig.
10, 2, _c_). In Wheat and Oats the cotyledon can be easily seen in the
largest seedlings by pulling off the dry husk of the grain. The food will
he seen to have been used up.

[Illustration: FIG. 10. 1. Germination of Indian corn. 2. Same more
advanced. _a_, caulicle; _c_1, first leaf of the plumule, sheathing the
rest; _c_2, second leaf; _c_3, third leaf of the plumule; _d_, roots.]

The series of Corn seedlings, at least, should be drawn as before and
the parts marked, this time with their technical terms. The following
questions should then be prepared.

CORN.

What are the parts of the seed?

Compare these parts with the Morning-Glory, Sunflower, Bean, and Pea.

Where is the food stored?

How many cotyledons have Corn, Wheat, and Oats?

How many have Bean, Pea, Morning-Glory, and Sunflower?

Compare the veins of the leaves of each class and see what difference you
can find.

This will bring up the terms dicotyledon and monocotyledon. _Di_ means
two, _mono_ means one. This difference in the veins, netted in the first
class, parallel in the second, is characteristic of the classes. Pupils
should have specimens of leaves to classify under these two heads.
Flowering plants are divided first into these two classes, the
Dicotyledons and the Monocotyledons.

If Pine-seeds can be planted, the polycotyledonous embryo can also be
studied.

7. _Food of seedlings_.--The food of the Wheat seedling may be shown in
fine flour. [1]"The flour is to be moistened in the hand and kneaded until
it becomes a homogeneous mass. Upon this mass pour some pure water and
wash out all the white powder until nothing is left except a viscid lump
of gluten. This is the part of the crushed wheat-grains which very closely
resembles in its composition the flesh of animals. The white powder washed
away is n