f this may frequently be met
with in the case of the vine.

In _Lamium album_ I have seen one of the verticillasters on one side of
the stem completely wanting, the adjacent leaf being, however, as fully
formed as usual.

=General remarks on suppression.=--On comparing together the various
whorls of the flower in reference to suppression, and, it may be added,
to atrophy, we find that these phenomena occur most rarely in the calyx,
more frequently in the corolla, and very often in the sexual
organs and seeds; hence it would seem as if the uppermost and most
central organs, those most subject to pressure and latest in date of
development--formed, that is, when the formative energies of the plant
are most liable to be exhausted--are the most prone to be suppressed or
arrested in their development. When the plants in which these
occurrences happen most frequently are compared together, it may be seen
that partial or entire suppression of the floral envelopes, calyx, and
corolla, is far more commonly met with in the polypetalous and
hypogynous groups than in the gamopetalous or epigynous series.

The orders in which suppression (speaking generally) occurs most often
as a teratological occurrence are the following:--_Ranunculaceae_,
_Cruciferae_, _Caryophyllaceae_, _Violaceae_, _Leguminosae_, _Onagraceae_,
_Jasminaceae_, _Orchidaceae_. It will be observed that these are all
orders wherein suppression of the whole or part of the outer floral
whorls takes place in certain genera as a constant occurrence.

Again, it may be remarked that many of these orders show a tendency
towards a regular diminution of the assumed normal number of their
parts; thus, among _Onagraceae_, _Circeia_ and _Lopezia_ may be referred
to, the former normally dimerous, the latter having only one perfect
petal. So in fuchsias, a very common deviation consists in a trimerous
and rarely a dimerous symmetry of the flower.

Although, if the absolute number of genera or orders be counted, there
appears to be little difference in the frequency of the occurrence of
suppression in irregular flowers as contrasted with regular flowers, yet
if the individual instances could be counted in the two groups
respectively it would be found that suppression is more common among
irregular than in regular flowers. Thus, the number of individual
instances of flowers in which the perianth is defective is comparatively
large among _Violaceae_, _Leguminosae_, and _Orchidace