Stems filiform, creeping; lvs orbicular, peltate, to 6 cm, commonly with 8-14 shallow lobes; infl (except in depauperate plants) a simple or once to thrice forked spike to 15 cm or even more, bearing 2-several whorls of fls, these rarely more than 7 per whorl; fr 3-4 mm wide, truncate to rounded at base, the margins acute. Mass. to Fla. and Tex., chiefly near the coast; w. U.S. and trop. Amer. June-Aug. Typical H. verticillata has the fls and frs sessile or subsessile. Plants with distinctly pedicellate fls and frs, the pedicels to 1 cm, occur over the same range and have been called var. triradiata (A. Rich.) Fernald. (H. canbyi; H. australis)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.