not wonderful that they are often replaced by
those organs.[254] A singular instance of this has been mentioned as
occurring in _Cakile maritima_, wherein the sepals were found by M.
Fournier to be pinnatifid like the ordinary leaves of the plant.[255]
The sepals of _Ranunculaceae_ and _Rosaceae_, for example, _Rosa_, _Geum_,
are particularly liable to this change.

[Illustration: FIG. 129.--Flower of rose, sepals replaced by five
perfect leaves; axis prolonged through the flower in the form of a leafy
branch.]

In a species of _Geranium_ recently examined the sepals presented
themselves in the form of three-lobed leaflets; so in fuchsias and in
_Epilobium hirsutum_ the sepals occasionally are not distinguishable
from ordinary leaves (fig. 130). In roses, the change in question is a
very frequent accompaniment of prolification (fig. 129). In the peach
also this replacement of the sepals is sometimes carried to such an
extent, that five perfect, bistipulate leaves occur in the place of the
calyx, but when this is the case it usually happens that the pistil is
abortive.

[Illustration: FIG. 130.--Fuchsia, with one of the sepals leaf-like.]

De Candolle[256] figures a curious instance wherein the pappus of
_Podospermum laciniatum_ was replaced by five linear, foliaceous lobes.
A similar change has been noticed in other composites, as in _Tragopogon
pratense_. Engelmann mentions as subject to this hypertrophy of the
pappus, as it may be termed, _Scorzonera octangularis_ and _Senecio
vulgaris_. Wigand has observed a similar transformation in a species of
_Centranthus_ (_Valerianaceae_).

In some cases the phyllody of the sepals has a special interest, as
bearing on the question whether what is termed calyx-tube is or is not a
portion of the calyx, and whether the sepals are modifications of the
blade or of the sheath of the leaf. Thus in the primrose the phyllodic
sepals seem to show clearly that the sepals are in that plant of a
laminar nature (fig. 131). The so-called calyx-tube of roses is
elsewhere alluded to. The leaf-like organs sometimes seen at the apex of
a cucumber would seem to support the view that there was really a
calyx-tube in _Cucurbitaceae_ adherent to the carpels. It is also shown
in the cut, fig. 132, borrowed from the 'Gardeners' Chronicle,' 1859,
p. 654.

[Illustration: FIG. 131.--Primrose. Calyx of foliaceous segments.]

[Illustration: FIG. 132.--Leafy calyx of melon.]

Under ordinary circums