t any other
alteration; at the same time the small corollas become green, and show a
tendency to assume a foliaceous condition. Sometimes the hypertrophy
affects also the styles of the central florets, and these also become
enlarged to double or treble their usual dimensions.

Linne has remarked that the ovary of _Tragopogon_ sometimes assumes very
large dimensions, as also does the pappus. He mentions a double-flowered
variety, the ovaries of which become ten or twelve times larger than
ordinary. M. Clos[503] records an instance in _Rumex scutatus_ wherein
the pistil was hypertrophied or club-shaped, and open at the top, or in
other cases funnel-shaped, three-lobed at the summit, each lobe
terminated by a style. One of the most frequent causes tending to the
hypertrophy of the pistil is attributable to the puncture of insects;
thus, when the ovary of _Juncus articulatus_ is thus punctured, it
acquires a size two or three times larger than ordinary, becoming at the
same time sterile.[504]

Occasionally the enlargement may be due to a fusion or incorporation of
other elements; thus, M. Lemaire describes an instance in which the
style of _Sinningia purpurea_ was much larger than ordinary, tubular,
bearing three small lobes, and altogether bearing much resemblance to
the column or "gynosteme" of Orchids. This appearance was due to the
cohesion and intimate union of the styles with three abortive
stamens.[505]

=Enlargement of the fruit.=--Most cultivated fruits are in a state of
true hypertrophy. Girod de Chantrans, after many trials, succeeded in
producing a peculiar variety of pea with pods double the ordinary
size.[506] M. Clos[507] mentions a case wherein the carpels of
_Delphinium dictyocarpum_ were hypertrophied. The change in size may or
may not be attended by a difference in form; thus, in certain
_Leguminosae_, as _Medicago lupulina_, _Melilotus leucantha_, the carpels
are sometimes hypertrophied and elongated, so as to resemble a claw or
hook.[508]

The fruit of the common groundsel (_Senecio vulgaris_) is in its normal
condition two or three times shorter than the involucre, and cylindrical
for its whole length, but it frequently happens that the fruits become
as long as the involucre itself, and taper from the base upwards, so as
to become beaked. Under this head may also be mentioned the fleshy
bulbils that are found in the capsules of _Crinum_, _Amaryllis_, and
_Agave_. These are true seeds enormously di