Cor salverform or broadly funnelform, the short tube closed by the fornices; stamens included; nutlets bearing conspicuous, stout, glochidiate prickles, attached to the gynobase near their connivent summits, their rounded bases divergent; gynobase prolonged beyond the nutlets into a conspicuous persistent subulate organ; taprooted, ±robust, leafy herbs, the fls pedicellate in axillary and terminal bractless false racemes. 80, cosmop.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.