ss additional ribs
stretch out from this towards the sides. The leaves now appear notched,
deeply indented, or composed of several small leaves, in which last case
they seem to form complete little branches. The date-palm furnishes a
striking example of such a successive transformation of the simplest
leaf form. A midrib is elongated through a succession of several
leaves, the single fan-shaped leaf becomes torn and diverted, and a very
complicated leaf is developed, which rivals a branch in form.
"The transition to inflorescence takes place more or less rapidly. In
the latter case we usually observe that the leaves of the stalk loose
their different external divisions, and, on the other hand, spread out
more or less in their lower parts where they are attached to the stalk.
If the transition takes place rapidly, the stalk, suddenly become
thinner and more elongated since the node of the last-developed leaf,
shoots up and collects several leaves around an axis at its end.
"That the petals of the calyx are precisely the same organs which have
hitherto appeared as leaves on the stalk, but now stand grouped about a
common centre in an often very different form, can, as it seems to me,
be most clearly demonstrated. Already in connection with the cotyledons
above, we noticed a similar working of nature. The first species, while
they are developing out of the seed-kernel, display a radiate crown of
unmistakable needles; and in the first childhood of these plants we see
already indicated that force of nature whereby when they are older their
flowering and fruit-giving state will be produced.
"We see this force of nature, which collects several leaves around an
axis, produce a still closer union and make these approximated, modified
leaves still more unrecognizable by joining them together either
wholly or partially. The bell-shaped or so-called one-petalled calices
represent these cloudy connected leaves, which, being more or less
indented from above, or divided, plainly show their origin.
"We can observe the transition from the calyx to the corolla in more
than one instance, for, although the color of the calyx is still usually
green, and like the color of the leaves of the stalk, it nevertheless
often varies in one or another of its parts--at the tips, the margins,
the back, or even, the inward side--while the outer still remains on
green.
"The relationship of the corolla to the leaves of the stalk is shown
in more
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