2. S. lancifòlia, L. Scape 2–5° high, with several of the lower whorls fertile; leaves lanceolate or lance-oblong, rarely linear, all with a tapering base, thick or coriaceous (6–18´ long and on a long and stout petiole, never sagittate), the nerves mostly arising from the very thick midrib; bracts ovate, acute or acuminate; pedicels slender, the fertile scarcely shorter than the sterile ones; filaments pubescent; achenes falcate, winged on the back, pointed with an incurved beak.—Swamps, Md. to Ky., Mo., and southward. (W. Ind.)
[*][*] Filaments very short, with enlarged mostly glandular base; anthers ovate or short-oblong; fruiting heads small; bracts more or less connate; leaves very rarely sagittate.
3. S. heterophýlla, Pursh. Scape weak (3´–2° high), at length procumbent; leaves lanceolate or lance-oval, entire, or with one or two narrow basal sagittate appendages; bracts roundish, obtuse; flowers of the lowest whorl fertile and almost sessile; the sterile on long pedicels; filaments glandular-pubescent; achenes narrowly obovate with a long erect beak.—N. Eng to Fla., west to Minn. and Mo. Varies as to foliage, the leaves being broad (var. ellíptica, Engelm.), or rigid and narrowly lanceolate with stout petioles (var. rígida, Engelm.), or nearly linear (var. angustifòlia, Engelm.)
4. S. gramínea, Michx. Scape 3´–2° high; phyllodia flat, mostly broadly linear, acuminate; leaves ovate-lanceolate to linear, on long slender petioles, sometimes reduced to the petiole merely; bracts rather obtuse; whorls of flowers often few, all staminate or the lower fertile; pedicels slender, spreading, nearly equal; filaments 15–20, glandular-pubescent; achene small (½´´ long), narrowly obovate, almost beakless, winged on the back, flat and scarcely costate on the sides.—N. Eng. to Minn., south to the Gulf; very variable.
5. S. tères, Watson. Phyllodia terete, very acutely attenuate upward, 3–12´ long, very rarely bearing a narrow blade; scape ½–1½° high; bracts connate at base; pedicels in 1–3 whorls, all very slender and spreading, 1 or 2 fruiting, ½–1´ long; filaments 12, dilated, pubescent; achene obovate, 1´´ long, with an erect beak, the margins and sides crenately several-crested.—In shallow water, S. New Eng. to N. J. (Hyannis, Mass., Deane; Wading River, L. I., Miller; barrens of N. J., Torrey.) Phyllodia usually very strongly nodose. (Addendum)—Sagittaria teres has been collected also at Brewster, Mass. (Farlow).
6. S. nàtans, Michx., var. loràta, Chapm. Usually dwarf; leaves linear, strap-shaped, obtuse or acutish, 1–6´ long, equalling or shorter than the scape, very rarely with a narrow blade; pedicels in 1–3 whorls, only 1 or 2 fruiting, stouter and recurved; bracts connate or spathe-like; filaments 6–8, glabrous; achene obovate, short-beaked, 1´´ long, the margins and sides crenately crested. (S. pusilla, Pursh.)—In mud or shallow water, near the coast; N. Y. to Fla.
Var. (?) gracíllima, Watson. Scape and the almost or wholly bladeless leaves very slender and greatly elongated (2–4° long, 1´´ wide); pedicels all elongated, in usually distant whorls, the lower pistillate, slender and spreading; fruit unknown. (S. natans, Engelm. in Torr. Bull. ix. 4.)—In deep water of streams in E. Mass. (Hitchings, Boott, C. E. Faxon, etc.) Wholly submerged, only 1 or 2 flowers appearing at a time, floating on the surface. The fruit, maturing under water, has not yet been collected.
§ 2. LOPHIOCÁRPUS. Fertile flowers perfect; stamens 9–15, at the base of the receptacle; sepals erect and embracing the fruit.
7. S. calycìna, Engelm. Scape weak (3–9´ high), at length mostly procumbent; usually only the lowest whorl fertile, with pedicels as long as those of the sterile flowers, recurved in fruit; bracts orbicular, obtuse or rarely pointed; filaments slightly rough, as long as the anthers; achenes obovate with a short horizontal style; leaves broadly halberd-shaped, obtuse or acutish, with wide spreading lobes, often wider than long, or lanceolate or sometimes reduced to linear phyllodia.—Maine to Del., west to Wisc., Mo., and Tex. Quite variable, several forms being enumerated, as var. spongiòsa, with spongy texture and bladeless submerged leaves, eastward; and westward, var. flùitans, with lance-linear floating leaves.
3. ECHINÓDORUS, Richard.