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..
Erect perennial herbs, with large 2-3-ternate leaves, and small spicate polygamous flowers in terminal panicles. Calyx campanulate, 4-5-lobed. Petals 4-5 (in our species), linear-spatulate, inserted at the base of the calyx. Stamens 8-10, all perfect, inserted with the petals; filaments elongated. Ovary superior or nearly so, 2-3-celled, deeply 2-3-lobed; styles 2-3) stigmas obtuse; ovules 00. Capsule 2-3-lobed, separating into 2-3 follicle-like carpels, each usually few-seeded. Seeds small, the testa loose, tapering at each end. [Greek, without brightness.]
About 7 species, natives of eastern North America, eastern Asia and the Himalayas. Besides the following another species occurs in the southern Alleghanies. Type species: Astilbe rivu~ làris D. Don.
Tiarella biternata Vent. Jard. Malm.
Club 20: 475. 1893.
Erect, 3°-6° high, more or less pubescent. Leaves petioled, 2-3-ternately compound, often 2° broad; leaflets thin, stalked, ovate, cordate, truncate or rounded at the base, the lateral ones usually oblique, acuminate at the apex, sharply serrate or incised, 2'-5' long; panicles often 1° long; flowers sessile or nearly so, about 2" broad, yellowish white; petals of the staminate flowers spatu-late, those of the perfect ones much smaller or none; stamens 10; follicles 2, acute, glabrous, about 1 1/2" long.