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..
Climbing vines, more or less woody. Leaves opposite, slender-petioled, pinnately compound. Flowers cymose-paniculate, our species dioecious, or nearly so. Sepals 4 or 5, valvate in the bud, spreading, petaloid. Petals none. Stamens numerous, spreading; filaments mostly glabrous; anthers short, blunt. Pistils numerous. Achenes 1-seeded. Style long, persistent, plumose. [Greek name for some climbing plant]
About 25 species of very wide geographic distribution. Besides the following, several others occur in the southern and western parts of North America. Type species: Clematis vitalba L.
Leaves 3-foliolate; eastern.
Leaves pinnately 5-7-foliolate; western.
Clematis virginiana L. Amoen. Acad. 4: 275. 1759.
A long vine, climbing over bushes in low woodlands and along fences and water-courses. Leaves glabrous or nearly so, trifoliolate; leaflets mostly broadly ovate, acute at the apex, toothed or lobed, sometimes slightly cordate; flowers white, in leafy panicles, polygamo-dioecious, 8"-15" broad when expanded; filaments glabrous; persistent styles plumose, 1' long or more.
Georgia to Tennessee, northward to Nova Scotia and Manitoba. Leaves rarely 5-foliolate. Ascends to 2600 ft. in Virginia. Woodbine. Traveler's-joy. Love-vine. Devil's-hair or -darning-needle. Wild hops. July-Sept.
Clematis missouriÚnsis Rydb., of Missouri, Kansas and Nebraska, differs in having marginless achenes and in being more pubescent; it has been confused with C. Catesbyana Pursh, of the southern states and may be specifically distinct.
C. ligusticifolia Nutt.; T. & G. Fl. N. A. 1: 9. 1838.
A trailing and climbing vine, nearly glabrous. Leaves pinnately 5-foliolate, the lower pair of leaflets generally remote from the upper; leaflets oblong or ovate-lanceolate, acute and sometimes acuminate at the apex, rounded or cuneate at the base, toothed, lobed or divided; flowers white, in leafy panicles, 6"-9" broad when expanded, the stamens about equalling the sepals; filaments glabrous; persistent styles plumose throughout, nearly white, 1'-2' long.