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..
Hibiscus Trionum L. Sp. Pl. 697. 1753.
Annual, depressed and branching from the base, pubescent with spreading hairs. Leaves petioled, ovate or orbicular in outline, pedately 3-7-lobed or divided, the lobes obtuse, dentate-crenate or cleft, the middle one longer; flowers pale yellow with a purple eye, •\'-2\' broad, axillary to the upper leaves, each one remaining open but a few hours; petals tinged with purple on the outer edge; bracts linear, ciliate, much shorter than the membranous beautifully nerved hispid-pubescent 5-angled inflated calyx; capsule globose-ovoid, hairy; seeds roughened with short processes.
Hibiscus Syriacus L. Sp. Pl. 695. 1753.
A branching nearly glabrous shrub, 10°-20° high. Leaves short-petioled, ovate, 2'-5' long, obtuse or cuneate at the base, acute but blunt at the apex, 3-5-lobed or the upper merely dentate, sometimes with a few scattered stellate hairs on the upper surface; flowers axillary, short-pedun-cled, pink or white with a crimson centre, 2'-4' broad; bractlets linear, shorter than the calyx, or slightly exceeding it; peduncles, bractlets and calyx stellate-pubescent; capsule ovoid, nearly 1' long.
Sparingly escaped from cultivation, Connecticut to Pennsylvania, the District of Columbia and Georgia. Introduced from western Asia. Aug.-Sept.