This section is from the book "Nature's Garden", by Neltje Blanchan. Also available from Amazon: Nature's Garden; An Aid To Knowledge Of Our Wild Flowers And Their Insect Visitors.
Flowers - Showy, purplish blue, about3 in. across; 4 sepals, broadly expanded, thin, translucent, strongly veined, very large, simulating petals; petals small, spoon-shaped; stamens very numerous; styles long, persistent, plumed throughout. Stem: Trailing or partly climbing with the help of leafstalks and leaflets. Leaves: Opposite, compounded of 3 egg-shaped, pointed leaflets on slender petioles.
Preferred Habitat - Rocky woodlands.
Flotvering Season - May - June.
Distribution - Hudson Bay westward, south to Minnesota and Virginia.
The day on which one finds this rare and beautiful flower in some rocky ravine high among the hills or mountains becomes memorable to the budding botanist. At an elevation of three thousand feet in the Catskills it trails its way over the rocks, fallen trees, and undergrowth of the forest, suggesting some of the handsome Japanese species introduced by Sieboldt and Fortune to Occidental gardens. No one who sees this broadly expanded blossom could confuse it either with the thick and bell-shaped purple Leather-flower (C. Viorna), so exquisitely feathery in fruit, that grows in rich, moist soil from Pennsylvania southward and westward; or with the far more graceful and deliciously fragrant purple Marsh Clematis (C. crispa) of our Southern States. The latter, though bell-shaped also, has thin, recurved sepals, and its persistent styles are silky, not feathery at seed-time.