ain, it may be
extra-floral. In this last case the prolification is of the
inflorescence, and is hardly distinguishable from multiplication or
subdivision of the common flower-stalk. In accordance with these
differences we have median, axillary, and extra-floral prolification,
each admitting of subdivision into a leafy or a floral variety,
according to the nature of the adventitious bud. Under the head of each
variety certain special peculiarities are noticed, but it may here be
advisable to add a few general remarks on the subject.

Axillary prolification is a much less frequent malformation than the
median form. If only the number of orders and genera be reckoned, the
truth of this statement will be scarcely recognised; but if individual
cases could be estimated, the difference in frequency between the two
would be very much more obvious. This may, perhaps, be explained by the
fact that the branch has a greater tendency to grow in length than it
has to develop buds from the axils of the leaves. The flower is admitted
to be homologous with the branch, and it is also known that, up to a
certain time, the branch-bud or leaf-bud and the flower-bud do not
essentially differ.[104] At a later stage the difference between the two
is manifested, not only in the altered form of the lateral organs in the
flower-bud, but in the tendency to an arrest of growth, thus limiting
the length of the central axial portion. Now, in prolified flowers the
functions and, to a considerable extent, the appearance of a leaf-bud or
of a branch are assumed, and with them the tendency to grow in length is
developed. Median prolification, therefore, in this sense, is a further
step in retrograde metamorphosis than is the axillary form. To grow in
length, and to produce axillary buds, are alike attributes of the
branch; but the former is much more frequently called into play than the
latter; for the same reason, median prolification is more common than
the axillary form. This is borne out by the frequency with which
apostasis, or the separation of the floral whorls one from another, to a
greater degree than usual, is met with in prolified flowers.

In both forms the adventitious growth is much more frequently a
flower-bud or an inflorescence than a leaf-bud or a branch. This may be
due to the position of the flowers on a portion of the stem of the plant
especially devoted to the formation of flower-buds, to the more or less
complete exclusion of lea