L. usitatíssimum, L. (Common Flax.) Annual; stem corymbosely branched at top; sepals acute, ciliate.—Occasionally spontaneous in fields. (Adv. from Eu.)
Order 23. GERANIÀCEÆ. (Geranium Family.)
Plants (chiefly herbs) with perfect and generally symmetrical hypogynous flowers; the stamens, counting sterile filaments, as many or commonly twice as many, and the lobes or cells (1–few-ovuled) of the ovary as many, as the sepals, the axis of the dry fruit persisting.—Seeds without albumen except in Oxalis. Flowers mostly 5-merous and the sepals usually distinct. Leaves never punctate. An order not easily defined, and including several strongly marked tribes or suborders which have been regarded by many botanists as distinct.
Tribe I. GERANIEÆ. (Geranium Family proper.) Flowers regular, 5-merous, the sepals imbricate in the bud, persistent. Glands of the disk 5, alternate with the petals. Stamens somewhat united. Ovary deeply lobed; carpels 5, 2-ovuled, 1-seeded, separating elastically with their long styles, when mature, from the elongated axis. Cotyledons plicate, incumbent on the radicle.—Herbs (our species) with more or less lobed or divided leaves, stipules, and astringent roots.
1. Geranium. Stamens with anthers 10, rarely 5. The recurving bases of the styles or tails of the carpels in fruit naked inside.
2. Erodium. Stamens with anthers only 5. Tails of the carpels in fruit bearded inside, often spirally twisted.
Tribe II. LIMNÁNTHEÆ. Flowers regular, 3-merous (in Flœrkea), the persistent sepals valvate. Glands alternate with the petals. Stamens distinct. Carpels nearly distinct, with a common style, 1-ovuled, 1-seeded, at length fleshy and indehiscent, not beaked, separating from the very short axis. Embryo straight, cotyledons very thick, radicle very short.—Low tender annuals, with alternate pinnate leaves and no stipules.
3. Flœrkea. Sepals, minute pistils, and lobes of the ovary 3, stamens 6.
Tribe III. OXALÍDEÆ. (Sorrel Family.) Flowers regular, 5-merous, the persistent sepals imbricate. Glands none. Stamens 10, often united at base. Stigmas capitate. Fruit a 5-celled loculicidal pod (in Oxalis); cells 2–several-seeded. Embryo straight, in a little fleshy albumen.—Leaves compound (3-foliolate in our species); juice sour.
4. Oxalis. Styles 5, separate. Pod oblong, the valves not falling away. Leaflets usually obcordate.