or Spring Cress.]

[Illustration: Fig. 402. Silicle of Shepherd's Purse.]

[Illustration: Fig. 403. Same, with one valve removed.]

[Illustration: Fig. 404. Pyxis of Purslane, the lid detaching.]

376. =The Pyxis= is a pod which opens by a circular horizontal line, the
upper part forming a lid, as in Purslane (Fig. 404), the Plantain,
Henbane, etc. In these the dehiscence extends all round, or is
_circumscissile_. So it does in Amaranth (Fig. 387), forming a
one-seeded utricular pyxis. In Jeffersonia, the line does not separate
quite round, but leaves a portion for a hinge to the lid.

377. Of Multiple or Collective Fruits, which are properly masses of
fruits aggregated into one body (as is seen in the Mulberry (Fig. 408),
Pine-apple, etc.), there are two kinds with special names and of
peculiar structure.

[Illustration: Fig. 405. A fig-fruit when young. 406. Same in section.
407. Magnified portion, a slice, showing some of the flowers.]

[Illustration: Fig. 408. A mulberry. 409. One of the grains younger,
enlarged; seen to be a pistillate flower with calyx becoming fleshy.
410. Same, with fleshy calyx cut across.]

378. =The Syconium or Fig-fruit= (Fig. 405, 406) is a fleshy axis or
summit of stem, hollowed out, and lined within by a multitude of minute
flowers, the whole becoming pulpy, and in the common fig, luscious.

379. =The Strobile or Cone= (Fig. 411), is the peculiar multiple fruit
of Pines, Cypresses, and the like; hence named _Coniferae_, viz.
cone-bearing plants. As already shown (313), these cones are _open
pistils_, mostly in the form of flat scales, regularly overlying each
other, and pressed together in a spike or head. Each scale bears one or
two naked seeds on its inner face. When ripe and dry, the scales turn
back or diverge, and in the Pine the seed peels off and falls, generally
carrying with it a wing, a part of the lining of the scale, which
facilitates the dispersion of the seeds by the wind (Fig. 412, 413). In
Arbor-Vitae, the scales of the small cone are few, and not very unlike
the leaves. In Cypress they are very thick at the top and narrow at the
base, so as to make a peculiar sort of closed cone. In Juniper and Red
Cedar, the few scales of the very small cone become fleshy, and ripen
into a fruit which closely resembles a berry.

[Illustration: Fig. 411. Cone of a common Pitch Pine. 412. Inside view
of a separated scale or open carpel; one seed in place: 413, the other
seed.]