H. Androssemum: undershrub; stems numerous, erect, 1 §-2 feet high, simple or slightly branched; leaves sessile, ovate, obtuse, cordate at the base, glabrous, with minute pellucid dots; flowers few, in small corymbs, yellow, the petals scarcely longer than the sepals; stamens numerous, connected at the very base into five clusters; styles three; capsule globular, slightly succulent before it is ripe. - Tutsan. - Open woods. Fl. July, August.
** Stamens triadelplious, i.e. in three groups or clusters. † Stems erect. ‡ Sepals entire.
H. perforatum: stems 1-1 1/2 feet high, branching above, cylindrical or with two slightly prominent opposite angles, glabrous; leaves sessile, oblong, marked with pellucid dots, and occasionally a few black ones beneath; flowers bright yellow, in a handsome terminal corymb; sepals with a few glandular lines or dots; petals twice as long, marked with black dots; stamens shortly united; styles 3. - Woods, hedges, and thickets. Fl. July and August.
H. quadrangulum: stem 1-2 feet high, with four prominent angles; leaves ovate, clasping the stem at the base, with numerous pellucid dots, and a few black ones round the margin beneath; flowers pale yellow; sepals lanceolate, pointed; petals with or without a few black dots. - Moist pastures. Fl. July, August.
‡‡ Sepals fringed.
H. pulchrum: stems 1-2 feet high, with short lateral branches, glabrous; leaves broadly cordate, clasping, those of the branches smaller, much narrower, all marked with pellucid dots; flowers in an oblong or pyramidal panicle, golden yellow; sepals broad, obtuse, fringed at the top with black, glandular teeth. - Dry woods, heaths, and wastes. Fl. July.
H. hirsutum: stem 1 1/2-2 feet high, nearly simple, downy or hairy; leaves oblong or elliptical, narrowed into a short stalk, hairy underneath on the veins, marked with numerous pellucid dots; flowers in an oblong or pyramidal panicle, pale yellow, the sepals narrow, fringed with rather long glandular teeth. - Woods and thickets. Fl. July, August.
†† Stems prostrate.
H. humifusum: stems decumbent, much branched, almost trailing, 2-6 inches long, sometimes forming dense spreading tufts; leaves oval-oblong, obtuse; flowers few, small, pale yellow, in short, loose, leafy cymes, the sepals oblong, anequal, entire or with a few glandular teeth, generally bordered by black dots; petals with few black dots. - Stony heaths, pastures, and bogs. Fl. July.
H. Elodes: stems diffuse, 6-12 inches long, covered with loose, woolly, whitish hairs; leaves orbicular, stem-clasping, woolly; flowers pale yellow, few together in a leafless cyme, at first terminal, but becoming lateral; sepals small, ovate, copiously fringed with glandular teeth; petals with a small fringed appendage at their base. - Spongy and watery bogs. Fl. July, August.