f can
grow directly from the root there is no stem: so that it is well first to
conceive of all plants as consisting of leaves and roots only, with the
condition that each leaf must have its own quite particular root[42]
somewhere. {154} Let a b c, Fig. 16, be three leaves, each, as you see,
with its own root, and by no means dependent on other leaves for its daily
bread; and let the horizontal line be the surface of the ground. Then the
plant has no stem, or an underground one. But if the three leaves rise
above the ground, as in Fig. 17, they must reach their roots by elongating
their stalks, and this elongation is the stem of the plant. If the outside
leaves grow last, and are therefore youngest, the plant is said to grow
from the outside. You know that 'ex' means out, and that 'gen' is the first
syllable of Genesis (or creation), therefore the old botanists, putting an
o between the two syllables, called plants whose outside leaves grew last,
Ex-o-gens. If the inside leaf grows last, and is youngest, the plant was
said to grow from the inside, and from the Greek Endon, within, called an
'Endo-gen.' If these names are persisted in, the Greek botanists, to return
the compliment, will of course call Endogens [Greek: Inseidbornides], and
Exogens [Greek: Houtseidbornides]. In the Oxford school, they will be
called simply Inlaid and Outlaid.

[Illustration: FIG. 18.]

3. You see that if the outside leaves are to grow last, they may
conveniently grow two at a time; which they accordingly do, and exogens
always start with two little {155} leaves from their roots, and may
therefore conveniently be called two-leaved; which, if you please, we will
for our parts call them. The botanists call them 'two-suckered,' and can't
be content to call them _that_ in English; but drag in a long Greek word,
meaning the fleshy sucker of the sea-devil,--'cotyledon,' which, however, I
find is practically getting shortened into 'cot,' and that they will have
to end by calling endogens, monocots, and exogens, bicots. I mean steadily
to call them one-leaved and two-leaved, for this further reason, that they
differ not merely in the single or dual springing of first leaves from the
seed; but in the distinctly single or dual arrangement of leaves afterwards
on the stem; so that, through all the complexity obtained by alternate and
spiral placing, every bicot or two-leaved flower or tree is in reality
composed of dual groups of leaves, separated by