Fls 4-8-merous; sep foliaceous, ±connate at base; cor funnelform, with short lobes; stamens included; ovary (2)3-4(-6)-locular, with a single axile ovule in each locule; fr separating into (2)3-4(-6) nutlets; herbs, mostly diffusely branched, with fls in terminal involucrate glomerules. 15, trop. Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.