, also cited by Moquin, found a specimen of _Bocconia_
with a corolla. _Arum maculatum_ has likewise been met with provided
with a genuine perianth as in _Acorus_ and other Orontiads. The unusual
development of the sexual organs in diclinous flowers has been alluded
to under the head of heterogamy, and other cases where the symmetry of
the flower is rendered regular, by the development of parts ordinarily
suppressed, will be found in the chapters relating to deviations from
the usual number of organs.

This change, or rather this persistence of a form that is usually
transient, is generally accompanied by some other alterations. Change of
direction, as has been already mentioned, is one of the most common of
these; separation of the petals (_Antirrhinum_, _Verbascum_, &c.), and
even their appearance in leaf-like guise, are not infrequent
(_Delphinium_, _Antirrhinum_, _Verbascum_, &c.) At other times
multiplication or increased number of the whorls of petals takes place,
often, but not always, at the expense of the sexual organs of the
flower. Perhaps even more frequent is the increased number of parts in
the same whorl in cases of regular peloria; thus, in the Pelargoniums
before alluded to, the parts of the flower are frequently regulated by
the number six instead of five.

This form of peloria is most generally met with in flowers that are
placed at the end or in the centre of the inflorescence, or in such
flowers as occur singly at the end of the flower-stalk, as in
_Tropaeolum_, _Viola_, &c. It would hence seem as if the freedom from
pressure or restriction on one side allowed the flower to develop
equally in all directions, and thus to produce regularity of form.

It is obvious, from what has been before said, that the process of
fertilisation is in many cases interfered with and altered by the change
in the conformation or the flower.

From overlooking the occasional existence of this form of peloria, new
genera have sometimes been formed on insufficient grounds. The genus
_Aceranthus_, for instance, consists of species of _Epimedium_ in which
the customary spurs are not formed.[229]

The occurrence both of regular and irregular peloria on the same plant
has frequently been observed in _Linaria_. It has also been remarked
that the seedlings raised from these forms are not always constant;
thus, the late Mr. Crocker, formerly foreman in the Royal Gardens, Kew,
informed me that he fertilised some flowers of a d