Common name. Lilies. Family Amaryllidaceae.
Sometimes included in Liliaceae.
Habit and leaf form. Herbs (usually tall). Perennial. Leaves basal (usually). Plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves. Young stems basal, short, herbaceous. Bulbaceous (tunicated, neck may be at ground level or above to form a pseudostem). On sandy seasonally flooded areas. Leaves alternate; spiral, or distichous; ‘herbaceous’; sessile; sheathing; simple. Leaf blades entire; flat, or solid; terete; linear, or lanceolate, or oblong, or ovate, or orbicular; broadly linear (to strap-shaped); parallel-veined; without cross-venules; sheathing. Leaves without stipules. Leaf blade margins entire. Leaves with a persistent basal meristem, and basipetal development. Leaf anatomy. Hairs absent. Extra-floral nectaries absent. Stem anatomy. Secondary thickening absent.
Reproductive type, pollination. Fertile flowers hermaphrodite. Unisexual flowers absent. Plants hermaphrodite. Floral nectaries present. Nectar secretion from the gynoecium.
Inflorescence and flower features. Flowers solitary, or aggregated in ‘inflorescences’; in umbels. The terminal inflorescence unit cymose. Inflorescences scapiflorous; terminal; scape axillary or arising beside the leaves, erect, unbranched, solid, leafless; with involucral bracts (2 bracts, spathe-like, surround the umbel); spatheate. Flowers pedicellate, or sessile; bracteate (numerous, linear, filiform, membranous or slightly coloured); ebracteolate; regular (more or less); 3 merous; cyclic; tetracyclic, or pentacyclic. Perigone tube present. Perianth of ‘tepals’; 6; 2 -whorled (3+3, but with a conspicuous ‘corona’, like an extra, inner whorl); isomerous; joined; petaloid; similar in the two whorls; white (mostly), or yellow, or pink. Androecial members definite in number. Androecium 6. Androecial members adnate; all equal; free of one another; nearly always 2 -whorled (3+3). Androecium exclusively of fertile stamens (at least, reduction to staminodes not mentioned by Dahlgren et al. 1985). Stamens 6 (in 2 whorls); all more or less similar in shape; isomerous with the perianth (rarely), or diplostemonous; at the throat of the perianth tube, opposite the segments; alterniperianthial; filantherous (the filaments sometimes appendaged alongside the anthers). Filaments appendiculate (the connate filaments sometimes expanded to form a staminal corona), or not appendiculate. Anthers dorsifixed (epipeltate), or basifixed (rarely); versatile; dehiscing via longitudinal slits; latrorse; tetrasporangiate. Gynoecium 3 carpelled. The pistil 3 celled. Carpels isomerous with the perianth. Gynoecium syncarpous; eu-syncarpous; inferior. Ovary plurilocular; 3 locular. Gynoecium stylate. Styles 1; apical. Stigmas 1; slightly 3 - lobed; capitate. Placentation axile. Ovules 1–12 per locule; non-arillate; anatropous.
Fruit and seed features. Fruit fleshy, or non-fleshy; indehiscent; a capsule. Capsules splitting irregularly, or loculicidal. Fruit 1-several per locule. Seeds endospermic. Endosperm oily. Seeds winged, or wingless. Cotyledons 1. Embryo straight. Testa encrusted with phytomelan, or without phytomelan.
Etymology. From the Greek for "lily".