Zephyranthes drummondii D. Don (syn. Cooperia pedunculata), giant rain–lily, prairie rain–lily, wide–leaf rain–lily, evening star rain–lily. Perennial herb, geophytic, bulb–bearing, fibrous–rooted, rosetted, scapose with 1 ascending inflorescence, in range 16—45 cm tall (aboveground); shoots with only basal leaves from bulb, leaves commonly 5—6, present at anthesis, gray–green and glaucous, glabrous, not odorous when crushed; bulb to 12 cm deep, oblate spheroid, to 35 × 50 mm, covered with papery old leaf sheaths and above the bulb having a persistent, brown cylinder to ground level of old leaf tissue (neck of tunic), cylinder 8—10 mm diameter, mother bulb not forming an obvious clusters of bulblets; adventitious roots from base of bulb
Stem (peduncle) cylindric, ca. 4 mm diameter, green from base upward, white belowground, hollow below flower node.
Leaves alternate distichous, simple and sheathing (including belowground portion); blade linear, in range 150+ × 7—8.3 mm, flat, entire, parallel–veined with many veins, midrib absent, glaucous.
Inflorescence flower solitary, terminal on peduncle (scape), in bud flower erect on short pedicel increasing in fruit, bracteate, glabrous; peduncle erect, cylindric, to 380 mm long, hollow; bractlet subtending pedicel closed, cylindric splitting from top to midpoint into 2 lobes, to 45 mm long, splitting also on 1 side of ovary but closed 10 mm, aging papery showing parallel veins; pedicel cylindric, 5—11+ mm long.
Flower bisexual, radial, to 45 mm across, to 85 mm long, sweetly fragrant; hypanthium above ovary cylindric (= perianth tube), ca. 40 × 2.6—2.9 mm, green to midpoint of hypanthium becoming white where tepals attached, thick–walled (to 1 mm); tepals 6 in 2 whorls, widely spreading, ± monomorphic, pure white aging with rose–purple, parallel–veined, of outer whorl ± elliptic, 38—45 × 16—17 mm, with short green to reddish point at tip, of inner whorl ovate, 39—45 × 20—24 mm, white at tip; stamens 6, attached at top of hypanthium and above bases of tepals at three different levels, included; filaments erect, unequal, free portion triangular (never slender), 0.5—3.5 mm long, white, glabrous; anthers dorsifixed, dithecal, 7—8 mm long, pale yellow, longitudinally dehiscent; pollen pale yellow; nectary on top of ovary; pistil 1; ovary inferior, cylindric, 3 mm diameter, green, glabrous, 3(—4)–chambered, each chamber with 12+ ovules in 2 vertical stacks; style included, to 2.5 × 0.7 mm (to about midpoint of hypanthium), white, flaring upward and unequally 3–lobed, each lobe with a terminal stigma.
Fruit capsule, loculicidal, dehiscent by 3(—4) widely spreading valves (ca. 20 mm across), 35—50+–seeded, before dehiscent conspicuously 3(—4)–lobed, 12—15 × 16—17 mm, green at base and mostly purplish above, when dehiscent with horizontal valves ± 20 mm across displaying flattened seeds projecting upward in 2 rows per chamber; pedicel in fruit 5—18 mm long.
Seed flattened D–shaped, 4.5—6 × 3—4 × 1.5—2 mm, glossy black, faces rough.
A. C. Gibson