6. H. adpréssum, Barton. Stem simple, herbaceous, from a slightly woody creeping base (1--2° high), obscurely 4-angled below and 2-edged above; _leaves ascending, lanceolate_ or linear-oblong, often acute, thin; cyme terminal, leafy at the base, few-flowered; sepals linear-lanceolate, pods ovoid-oblong.--Moist places, Nantucket and R. I. to Penn., and southwestward. July--Aug.--Leaves 1½´ long. Petals bright yellow, 3--5´´ long.
[+][+] _Pod 1-celled with 3 parietal placentæ._
7. H. dolabrifórme, Vent. Stems branched from the decumbent base, woody below (6--20´ high), terete; _leaves linear-lanceolate_, widely spreading, veinless; cyme leafy, few-flowered; _sepals oblong or ovate-lanceolate_, about the length of the very oblique petals (5--6´´ long); _pods ovate-conical, pointed_, the walls very thick and hard.--Dry hills and rocks, barrens of Ky. and Tenn. June--Aug.
8. H. cistifòlium, Lam.! Stems mostly simple, herbaceous, with a somewhat woody base, angled with 4 very narrow salient lines (1--2° high); leaves narrowly oblong to nearly linear (1--3´ long), sessile with a somewhat clasping base; the cyme naked, compound, usually many-flowered; _sepals ovate; pods depressed-globular or ovoid-conical_; seeds large, oblong, very rough-pitted. (H. sphærocarpon, _Michx._)--Rocky river-banks, S. W. Ohio, to Iowa and southward. July--Sept.--Flowers small.
9. H. ellípticum, Hook. Stem simple, herbaceous (10--20´ high), obscurely 4-angled; _leaves spreading, elliptical-oblong_, obtuse, usually narrower toward the subclasping base, thin; cyme nearly naked, rather few-flowered; _sepals oblong; pods ovoid, very obtuse_; seeds minutely striate.--Wet places, New Eng. and Penn. to Minn., and northward. July, Aug.--Petals light yellow, 3´´ long.
10. H. virgàtum, Lam. Stem slender, strict, simple, sharply 4-angled, herbaceous (1--2° high); _leaves ascending_, opaque, ovate or oblong-lanceolate, acute (½--1´ long), closely sessile by a broad base; cyme compound, naked, the scattered flowers racemose on its ascending branches; _sepals herbaceous, erect_, enclosing the ovoid pod; _styles 3, separate_, with capitate stigmas. (H. angulosum, _Michx._)--Wet pine barrens of N. J. and southward; Ky. July--Sept.--Petals copper-yellow, 4--5´´ long.