Fig. 356.—Flower of Polygonum fagopyrum in longitudinal section: 1, long-styled; 2, short-styled; a the anthers; st the stigmas; n nectary.
Order 2. Piperaceæ (Peppers). Shrubs or herbs, often with nodose, jointed stem; leaves simple, entire, often with curved veins; stipules wanting (Peperomia) or intrapetiolar and cap-like, often enclosing the terminal buds (Piper). The flowers in the group Pipereæ (Piper, Fig. [357], and Peperomia) are borne in spikes with fleshy axes (club-like), seldom in racemes, the outer ones are crowded and are ☿ or unisexual, always small, naked and without bracteoles; generally stamens 3 + 3, and gynœceum 3, but the number of the stamens may be reduced by suppression to 2, and the carpels to 1. The flowers are situated in the axils of the small, generally shield-like floral-leaves. The ovary is always unilocular and has one upright, orthotropous ovule. Fruit a berry or drupe. Both endosperm and perisperm are present, the latter being especially well developed (Fig. [359]).
Piper; generally shrubs with scattered leaves, and terminal inflorescences which are crowded to one side by the development of the highest lateral bud, so that they are situated opposite the leaves (Fig. [357]). Many species have stems with an abnormal anatomical structure.—Peperomia; chiefly succulent herbs, often epiphytes, with opposite or verticillate leaves having aqueous tissue on the upper side.
Fig. 357.—Piper nigrum: branch with fruit (½)
The group Saurureæ (considered by some as an order, and perhaps representing a more original type) has 3–4 carpels with many ovules. Lactoris stands the highest with regular 3-merous perianth, 3 + 3 stamens and 3 carpels, which are united at the base. Fruit a capsule with several seeds. (It has one species from the island of Juan Fernandez, and is also placed in an order of its own, Lactoridaceæ, allied to the Magnoliaceæ, through Drimys).—Saururus has naked flowers; most frequently 6 stamens, and 4 carpels, free or united at the base, each with 2-4 orthotropous ovules. Fruit, small berries.—Houttuynia; stamens situated a little upward on the ovaries; placentation parietal; capsule many-seeded.
About 1,000 species; entirely tropical, especially from South America and East India. They are found chiefly among the underwood in damp, shady places; some, which are fleshy (Peperomia), live as epiphytes on trees; a few climb by roots.—Uses. Several Piperaceæ are used medicinally and for spices on account of their pungent properties and the essential oils found in nearly all parts of the plant. The following are officinal: “Black-pepper” (the unripe, dried fruits) and “White-pepper” (the seeds of the ripe fruits) of Piper nigrum (climbing shrub, East Indian); “Cubeb” berries of P. cubeba (climbing shrub, Java). “Long-pepper” is the unripe inflorescence of P. longum, East India. The leaves of P. angustifolia (Matico) are officinal. The leaves of the Betelpepper (East India) are used together with the nuts of the Areca-palm to form the well-known East Indian intoxicating compound “Betel.” A good many others are also used.
Fig. 358.—Piper nigrum (Diagram). In addition to the bract there are two structures resembling bracteoles.
