lished a different explanation as to the nature of the hip of the
rose, having been led to his opinion by the conclusion that he has
arrived at, that the leaf is to be considered in the light of a
flattened branch, whose upper or posterior surface is more or less
completely atrophied.

According to M. de Candolle, the calyx-tube, in the case of the rose, is
neither a whorl of leaves, nor a concave axis in the ordinary sense in
which those terms are used, but is rather to be considered as a
ring-like projection from an axis arrested in its ulterior development.
The secondary projections from the original one correspond to an equal
number of vascular bundles, and develope into the sepals, petals,
stamens, and ovaries. If these organs remained in a rudimentary
condition, the tube of the calyx would be reduced to the condition of a
sheathing leaf. The rose flower, then, according to M. de Candolle, may
be considered as a sheathing leaf, whose fibro-vascular system is
complete, and from which all possible primary projections are
developed.[464]

If, as M. de Candolle considers, the leaf and the branch differ merely
in the fact that the vascular system is complete in the latter, and
partly atrophied in the former, it would surely be better to consider
the "calyx-tube" of the rose as a concave axis rather than as a leaf,
seeing that he admits the fibro-vascular system to be complete in the
case of the rose.

With reference to this point the reader is referred to Mr. Bentham's
account of the morphology and homologies of the _Myrtaceae_ in the
'Journal of the Linnean Society,' vol. x, p. 105. See also _ante_, pp.
71, 77.

Some doubts also exist as to the nature of the beak or columella of such
fruits as those of _Geraniaceae_, _Malvaceae_, _Umbelliferae_,
_Euphorbiaceae_, &c. The nature of the organ in question may probably be
different in the several orders named; at any rate the subject cannot be
discussed in this place, and it is mentioned here because, now and then,
it happens that the organ in question is completely wanting, and hence
affords an illustration of suppression.

FOOTNOTES:

[464] 'Theorie de la feuille.' p. 24.

CHAPTER II.

SUPPRESSION OF FOLIAR ORGANS.

This subject may be considered, according as the separate leaves of the
stem or of the flower are affected, and according as either the number
of members of distinct whorls, or that of the whorls themselves, is
diminished.

The terms aph