[*] Stem simple or loosely branched; leaves linear to ovate, spreading.
12. H. mùltilum, L. Stem flaccid, widely branching (6–20´ high); leaves ovate to narrowly oblong, obtuse, partly clasping, 5-nerved; cymes leafy; flowers 2´´ broad; pods ovate-conical, rather longer than the calyx.—Low grounds, everywhere.
13. H. gymnánthum, Engelm. & Gray. Almost simple, with strict stem and branches (1–3° high); leaves clasping, heart-shaped, acute or obtuse; cyme naked, the floral leaves reduced to small awl-shaped bracts; in aspect approaching the next. (H. mutilum, var. gymnanthum, Gray.)—Del. and Penn. to Minn., and southward.
14. H. Canadénse, L. Stem strict (6–15´ high), with the branches erect; leaves linear, 3-nerved at the base, obtuse; cymes naked; flowers deep yellow, 2–3´´ broad when expanded; pods conical-oblong, usually much longer than the calyx.—Wet, sandy soil; common. June–Oct.—Var. màjus, Gray, is a large form, 1–2° high, with lanceolate leaves 1½´ long, 3´´ wide, the upper acute. L. Superior, Robbins; S. New York and southward.—Var. minimum, Chois., a simple few-flowered form, 1–3´ high, with oblong obtuse leaves. On wet rocks, Wisc., and northward.
[*][*] Stems fastigiately branched; leaves linear or bract-like, ascending or appressed.
15. H. Drummóndii, Torr. & Gray. Stem and the mostly alternate bushy branches rigid, erect (10–18´ high); leaves linear-subulate, nearly erect, 1-nerved (3–9´´ long); flowers scattered along the upper part of the leafy branches, short-pedicelled; pods ovoid, not longer than the calyx.—W. Ill., Iowa, Kan., and southward, in dry soil.
16. H. nudicaùle, Walt. (Orange-grass. Pine-weed.) Stem and bushy branches thread-like, wiry (4–9´ high); leaves minute awl-shaped scales, appressed; flowers minute, mostly sessile and scattered along the erect branches; pods ovate-lanceolate, acute, much longer than the calyx. (H. Sarothra, Michx.)—Sandy fields, N. Eng. to Ill., Mo., and southward; common. June–Oct.
3. ELÒDES, Adans. Marsh St. John's-wort.
Sepals 5, equal, erect. Petals 5, equal-sided, oblong, naked, imbricated in the bud. Stamens 9 (rarely more), united in 3 sets; the sets separated by as many large orange-colored glands. Pod 3-celled, oblong, styles distinct.—Perennial herbs, in marshes or shallow water, with small close clusters of flesh-colored flowers in the axils of the leaves and at the summit of the stem. (Name ἑλώδης, growing in marshes, accidentally changed to Elodèa by Jussieu, who was followed by Pursh, etc.)
1. E. campanulàta, Pursh. Leaves closely sessile or clasping by a broad base, oblong or ovate, very obtuse; filaments united below the middle. (E. Virginica, Nutt.)—Common in swamps; 1–2° high. July, Aug.