This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", 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..
Perennial leafy herbs, with opposite or verticillate simple entire leaves, and axillary slender-peduncled nodding or spreading yellow flowers. Calyx 5-parted, persistent, the segments valvate in the bud. Corolla rotate, deeply 5-parted, with no proper tube, the lobes cuspidate or erose-denticulate, each separately involute or convolute around its stamen. Stamens 5; filaments distinct, or united into a ring at the very base, granulose-glandular; anthers linear, becoming curved; staminodia 5, subulate, alternate with the stamens. Ovary globose; ovules few or numerous. Capsule 5-valved, several-many-seeded. Seeds margined or angled. [Greek, sterile threads, from the abortive stamens.]
About five species, natives of North America. Type species: Steironema ciliatum (L.) Raf.
Leaves membranous, pinnately veined.
Leaves ovate or ovate-lanceolate.
Stem erect; flowers 6"-12" broad.
Petioles strongly ciliate: capsule longer than the calyx.
Petioles not ciliate, or slightly so at base; capsule not longer than calyx.
Stem reclined; flowers 3"-4" broad; leaves not ciliate; petioles naked
Leaves lanceolate, oblong or linear; stem erect.
Leaves firm, linear, 1-nerved, the lateral veins obscure.
Lysimachia ciliata L. Sp. Pl. 147. 1753. Steironema ciliatum Raf. Ann. Gen. Phys. 7: 192. 1820.
Stems erect, simple or branched, slender, mostly glabrous, 1°-4° high. Leaves membranous, ovate, ovate-oblong, or ovate-lanceolate, pinnately veined, acute or acuminate at the apex, obtuse, truncate or cordate at the base, 2'-6' long, 1/2'-3' wide, the margins ciliolate; petioles ciliate, 1/4'-1/4' long; peduncles filiform, 1'-2' long; calyx-segments lanceolate, acuminate, shorter than the erose-denticulate commonly mucronate corolla-segments; flowers 6"-12" broad; capsule longer than the calyx.
In moist thickets, Nova Scotia to British Columbia, south to Georgia, Alabama, Kansas, New Mexico and Arizona. Ascends to 6300 ft. in North Carolina. Naturalized in Europe. June-Aug.