Order 21. TILIÀCEÆ. (Linden Family.)
Trees (rarely herbs), with the mucilaginous properties, fibrous bark, valvate calyx, etc., of the Mallow Family; but the sepals deciduous, petals imbricated in the bud, the stamens usually polyadelphous, and the anthers 2-celled. Represented in Northern regions only by the genus,
1. TÍLIA, Tourn. Linden. Basswood.
Sepals 5. Petals 5, spatulate-oblong. Stamens numerous; filaments cohering in 5 clusters with each other (in European species), or with the base of a spatulate petal-like body placed opposite each of the real petals. Pistil with a 5-celled ovary, and 2 half-anatropous ovules in each cell, a single style, and a 5-toothed stigma. Fruit dry and woody, indehiscent-globular, becoming 1-celled and 1–2-seeded. Embryo in hard albumen; cotyledons broad and thin, 5-lobed, crumpled.—Fine trees, with soft and white wood, very fibrous and tough inner bark, more or less heart-shaped and serrate alternate leaves (oblique and often truncate at the base), deciduous stipules, and small cymes of flowers, hanging on an axillary peduncle which is united to a ligulate membranaceous bract. Flowers cream-color, honey-bearing, fragrant. (The classical Latin name.)
1. T. Americàna, L. (Basswood.) Leaves large, green and glabrous or nearly so, thickish; floral bract usually tapering at base; fruit ovoid.—Rich woods. May, June.—Here rarely called Lime-tree, oftener White-wood, commonly Basswood; the latter name now obsolete in England.
2. T. pubéscens, Ait. Leaves smaller (2–3´ long), thinner, and rather pubescent beneath; floral bract usually rounded at base; fruit globose, smaller (3´´ broad). (T. Americana, var. pubescens, Man.)—N. Y. to Fla., and westward.
3. T. heterophýlla, Vent. (White Basswood.) Leaves larger, smooth and bright green above, silvery-whitened with a fine down underneath.—Mountains of Penn. to S. Ill., and southward.
T. Europæ̀a, the European Linden, several varieties of which are planted in and near our cities for shade, is at once distinguished from any native species by the absence of the petal-like scales among the stamens. This tree (the Lin) gave the family name to Linnæus.
Order 22. LINÀCEÆ. (Flax Family.)
Herbs (rarely shrubs) with the regular and symmetrical hypogynous flowers 4–6-merous throughout, strongly imbricated calyx and convolute petals, 5 stamens monadelphous at base, and an 8–10-seeded pod, having twice as many cells as there are styles. Represented by the genus,