leaves is evident
from their appearance; they are commonly called the leaves of the
flower. The calyx is most generally green in color, and foliaceous
(leaf-like) in texture. And though the corolla is rarely green, yet
neither are proper leaves always green. In our wild Painted-cup, and in
some scarlet Sages, common in gardens, the leaves just under the flowers
are of the brightest red or scarlet, often much brighter-colored than
the corolla itself. And sometimes (as in many Cactuses, and in Carolina
Allspice) there is such a regular gradation from the last leaves of the
plant (bracts or bractlets) into the leaves of the calyx, that it is
impossible to say where the one ends and the other begins. If sepals are
leaves, so also are petals; for there is no clearly fixed limit between
them. Not only in the Carolina Allspice and Cactus (Fig. 229), but in
the Water-Lily (Fig. 228) and in a variety of flowers with more than one
row of petals, there is such a complete transition between calyx and
corolla that no one can surely tell how many of the leaves belong to the
one and how many to the other.

[Illustration: Fig. 228. Series of sepals, petals, and stamens of White
Water-Lily, showing the transitions.]

[Illustration: Fig. 229. A Cactus blossom.]

246. That stamens are of the same general nature as petals, and
therefore a modification of leaves, is shown by the gradual transitions
that occur between the one and the other in many blossoms; especially in
cultivated flowers, such as Roses and Camellias, when they begin to
_double_, that is, to change their stamens into petals. Some wild and
natural flowers show the same interesting transitions. The Carolina
Allspice and the White Water-Lily exhibit complete gradations not only
between sepals and petals, but between petals and stamens. The sepals of
our Water-Lily are green outside, but white and petal-like on the
inside; the petals, in many rows, gradually grow narrower towards the
centre of the flower; some of these are tipped with a trace of a yellow
anther, but still are petals; the next are more contracted and
stamen-like, but with a flat petal-like filament; and a further
narrowing of this completes the genuine stamen.

247. Pistils and stamens now and then change into each other in some
Willows; pistils often turn into petals in cultivated flowers; and in
the Double Cherry they are occasionally replaced by small green leaves.
Sometimes a whole blossom changes into