This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Glabrous herbs with coated bulbs, narrow leaves, and erect i-flowered scapes, the flower large, erect, pink, white or purple. Perianth funnelform, naked in the throat, with 6 membranous equal erect-spreading lobes united below into a tube, subtended by an entire or 2-cleft bract. Stamens inserted on the throat of the perianth, equal or nearly so; anthers versatile. Ovary 3-celled; style long, filiform, 3-cleft at the summit; ovules numerous, in 2 rows in each cavity of the ovary. Capsule thin-walled, subglobose or depressed, 3-lobed loculi-cidally 3-valved. Seeds mostly flattened, black or nearly so. [Greek, signifying wind-flower.]
Amaryllis Atamasco L. Sp. PI. 292. 1753. Zephyranthes Atamasco Herb. App. Bot. Reg. 36. 1821. Atamosco Atamasco Greene, Pittonia 3: 187. 1897.
Bulb ovoid, about 1' long. Leaves fleshy, somewhat concave, shining, 6'-15' long, about l 1/2"-3" wide, blunt, usually shorter than the scape; scape terete, erect, 2"-3" in diameter; bract membranous, 2-cleft into acuminate lobes, longer than the ovary; flowers 2'-3 1/2' high, white with a purplish tinge or sometimes light purple; perianth-segments oblong-lanceolate, acute, shorter than the tube; stamens shorter than the perianth; style longer than the stamens; capsule depressed, about 1/2" high.
In moist places, southern Pennsylvania to eastern Virginia, Florida and Alabama. Perianth rarely 8-lobed. Swamp-, Fairy- or Easter-lily. March-June.