ks up crosswise into
distinct joints, as in Fig. 394.
369. The pods or dehiscent fruits belonging to a compound ovary have
several technical names: but they all may be regarded as kinds of
370. =The Capsule=, the dry and dehiscent fruit of any compound pistil.
The capsule may discharge its seeds through chinks or pores, as in the
Poppy, or burst irregularly in some part, as in Lobelia and the
Snapdragon; but commonly it splits open (or is _dehiscent_) lengthwise
into regular pieces, called VALVES.
[Illustration: Fig. 395. Capsule of Iris, with loculicidal dehiscence;
below, cut across.]
[Illustration: Fig. 396. Pod of a Marsh St. John's-wort, with septicidal
dehiscence.]
371. Regular _Dehiscence_ in a capsule takes place in two ways, which
are best illustrated in pods of two or three cells. It is either
_Loculicidal_, or, splitting directly into the _loculi_ or cells, that
is, down the back (or the dorsal suture) of each cell or carpel, as in
Iris (Fig. 395); or
_Septicidal_, that is, splitting through the partitions or _septa_, as
in St. John's-wort (Fig. 396), Rhododendron, etc. This divides the
capsule into its component carpels, which then open by their ventral
suture.
[Illustration: Fig. 397, 398. Diagrams of the two modes.]
[Illustration: Fig. 399. Diagram of septifragal dehiscence of the
loculicidal type. 400. Same of the septicidal or _marginicidal_ type.]
372. In loculicidal dehiscence the valves naturally bear the partitions
on their middle; in the septicidal, half the thickness of a partition is
borne on the margin of each valve. See the annexed diagrams. A variation
of either mode occurs when the valves break away from the partitions,
these remaining attached in the axis of the fruit. This is called
_Septifragal_ dehiscence. One form is seen in the Morning-Glory (Fig.
400).
373. The capsules of Rue, Spurge, and some others, are both loculicidal
and septicidal, and so split into half-carpellary valves or pieces.
374. =The Silique= (Fig. 401) is the technical name of the peculiar pod
of the Mustard family; which is two-celled by a false partition
stretched across between two parietal placentae. It generally opens by
two valves from below upward, and the placentae with the partition are
left behind when the valves fall off.
375. =A Silicle or Pouch= is only a short and broad silique, like that
of the Shepherd's Purse, Fig. 402, 403.
[Illustration: Fig. 401. Silique of a Cadamine
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