and of the inferences to be derived from them has been given. It may be
useful to give in conclusion a few general remarks on the whole subject.

It will be seen from the numerous facts herein cited, that the so-called
monstrous formations (excluding morbid growths the result of disease or
injury) present no peculiarities absolutely foreign to the normal
organisation of plants. The difference between the natural and monstrous
development is one of degree and frequency of occurrence, not of kind.

Deviations from the customary form have been shown to arise from
excessive or diminished growth, or from arrested or exalted development.
Even in those instances where, for convenience' sake, the term perverted
development has been used, it must be understood as applying only to the
particular plant or organ under consideration, as the form assumed is
perfectly in accordance with the ordinary conformation of some other
plant or group of plants.

The period at which malformations occur is a matter of some importance;
this is, indeed, implied in the term arrest of development; evolution
goes on with growth up to a certain point and is then stopped, and thus
changes are brought about in the part affected of a different nature
from those dependent on non-development or suppression.

Some malformations are congenital, therefore, while others are
acquired--in the former instance the disturbance is coeval in origin,
and contemporaneous in its growth and development, with those of the
affected part; in the latter case the organ may have attained its
ordinary degree of perfection, or at least may have advanced some way
towards it, before any deviation shows itself. True chorisis or fission,
for instance, is usually a congenital affection, arising at a very early
period of development, while enation takes place from structures which
are all but complete as to their organisation, even though they may not
have attained their full dimensions. The date of appearance is also of
consequence in determining the true nature of some changes; it does not
always follow, for instance, that because one organ occupies the
position of another, it is of the same nature as the one whose place it
fills. The presence of anthers on petals or on such organs as the corona
of _Narcissus_ does not necessarily constitute those parts actual
stamens, but rather staminodes. The true stamens are either wanting, or
if present, they are in advance of their imitators