Lvs broadly ovate to subrotund, abruptly acuminate, with rounded basal sinus; cor ovoid in bud, at anthesis brownish-purple, its lobe widely spreading, elliptic, 7–12 mm, two-fifths to half as wide, minutely hairy outside; corona cupulate, variable, alternate lobes short and broad or narrower, somewhat prolonged, and bifid; pollen-sacs as in spp. 4 and 5, obvious, with open slits, the pollinia ± horizontal; fr 10–16 mm, sharply muricate, not angled. Moist woods and thickets; s. U.S., n. to Del., Md., Ky., and s. Mo. June, July. (Gonolobus c.; Odontostephana c.; Vincetoxicum c.; V. hirsutum)