Sagittaria calycina Engelm.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Annual, erect, or lax in deep-water forms; petioles elongate, terete, very spongy, typically with emersed or floating, hastate or sagittate blade 4–60 cm, the terminal lobe linear to deltoid-orbicular, the basal lobes large, pointed, divergent; small or deep-water forms with only submersed, linear lvs to 0.5 cm wide; scape stout, terete, 1–15 dm; fls in 3–12 whorls, the upper staminate, on long, slender pedicels, the middle and lower perfect, on somewhat shorter, stout, recurved pedicels; bracts mostly ovate, connate below, very thin and soon withering; sep 4–12 mm, broad, blunt, appressed to the fruiting head; pet 7–15 mm; stamens 9–12 in perfect fls, 12–many in staminate ones; filaments roughened with minute scales; achenes 2–3 mm, narrowly winged on the dorsal and ventral margins only, the sides wingless, the oblique or horizontal beak often more than half as long as the width of the body; 2n=22. Marshes, ponds, and streams, in circumneutral or alkaline waters; drainage of the Mississippi R. (sens. lat.), n. to lakes Michigan and Erie, s. to Tex., N.M., and Mex., and apparently e. sporadically to Del.; Calif. June–Oct. (S. montevidensis ssp. c.; Lophotocarpus c.; L. depauperatus)