Order XII. LINEÆ.
Herbs or shrubs, rarely trees. Leaves alternate, simple, usually entire; stipules present or wanting. Flowers regular, hermaphrodite. Sepals 5, rarely 4, free or coherent at the base, imbricate. Petals the same number, hypogynous or slightly perigynous, imbricate, often contorted. Stamens as many as the petals or twice as many, rarely more; filaments united below into a ring which frequently has 5 small glands at the base; anthers 2-celled, versatile. Ovary free, entire, 3–5-celled; styles the same number, distinct or more or less united; ovules 1–2 in each cell, pendulous, anatropous. Fruit either a capsule splitting into 3–5 cocci, or more rarely a drupe. Seeds 1–2 in each cell; albumen fleshy or wanting; embryo usually straight, radicle superior.
A small order, scattered over the whole world, the herbaceous species mainly temperate, the shrubby almost all tropical. Genera 14; species about 140. The common flax, Linum usitatissimum, so valuable from the tenacity of its fibre and its oily seeds, is the most important member of the order. The Peruvian Erythroxylon coca yields the important drug cocaine, and the leaves are chewed as a stimulant. The only New Zealand genus is widely distributed.
1. LINUM, Linn.
Herbs, rarely shrubby at the base. Leaves usually alternate, narrow, quite entire; stipules generally wanting. Flowers in panicled or racemose or fascicled cymes. Sepals 5, entire. Petals 5, contorted in æstivation, fugacious. Stamens 5, alternate with the petals, hypogynous, usually connate at the base, often alternating with 5 minute staminodia. Disc of 5 glands opposite to the petals and adnate to the staminal ring. Ovary 5-celled, with 2 ovules in each cell; cells sometimes divided into 2; styles 5. Capsule 5-celled, septicidally splitting into 5 2-seeded or 10 1-seeded cocci. Seeds compressed, albumen scanty.
A genus of 80 species or more, mostly natives of temperate or subtropical climates. The single indigenous species is endemic.
(The Australian L. marginale, A. Cunn., is now plentifully naturalised in many parts of New Zealand, especially to the north of Taranaki and Hawke's Bay. It can be distinguished from L. monogynum by its smaller size, more slender habit, and small pale-blue flowers.)
1. L. monogynum, Forst. Prodr. n. 145.—A very variable perfectly glabrous perennial herb, sometimes woody at the base; stems few or many, simple or branched, erect or spreading, 6–24 in. high. Leaves numerous, scattered, ascending, ¼–1 in. long, linear-oblong to linear-lanceolate or linear-subulate, 1–3-nerved. Flowers in terminal corymbs, white, often large and handsome, sometimes 1 in. diam. Sepals ovate or ovate-lanceolate, acute. Styles united at the base, their tips free, recurved. Capsule large, broadly ovoid, splitting into 10 1-seeded cocci.—A. Rich. Fl. Nouv. Zel. 317; A. Cunn. Precur. n. 608; Hook. Bot. Mag. t. 3574; Raoul, Choix de Plantes, 47; Hook. f. Fl. Nov. Zel. i. 28; Handb. N.Z. Fl. 35; Kirk, Students' Fl. 77.
North and South Islands, Stewart Island, Chatham Islands: Abundant along the coasts, and occasionally found inland, ascending to almost 2000 ft. on the mountains of the South Island. October–January.
A very beautiful but highly variable plant.