Erect, perennial herbs; rootstock horizontal; stem-base (? always) provided with 2 elongated, spindle-shaped, subterranean tubers. Leaves decussate, dentate to pinna-tifid, exstipulate, mostly crowded into a basal pseudo-rosette, cauline ones distant, gradually reduced; base decurrent into the petiole; petioles clasping the stem. Panicle terminal, bracteate, branches decussate, forked, cymose, outermost in triads; rachis and branches distinct from the stem by the presence of capitate-glandular hairs. Flowers ☿, articulated on a short pedicel, 5-merous, subactinomorphic. Base of the pedicel sustained by 2 narrow, ciliate, 1-nerved bracts ending in a thickened (?glandular), blunt nerve-tip. Ovary surrounded by 4 conspicuously capitate-glandular, persistent bracts connate at their extreme base and cuspidulate (in fruit hooked) at their apex (outer epicalyx) and a tubular, 8-ribbed, utricle-shaped, persistent inner epicalyx with a slight constriction at its apex below a minute, crenulate or toothed limb. Calyx minute, epigynous, 5-lobed. Corolla epigynous, gamophyllous, white, pink or red, caducous; tube funnel-shaped; lobes 5, equal, rounded, erect, imbricate in bud. Stamens 4, equal, alternating with the lobes; filaments free towards the apex of the tube; anthers intrors, dorsifixed. Style 1, terete, stigma capitate. Ovary 1-celled, narrow. Ovule 1, pendulous from the apex of the cell to halfway the ovary. Fruit 1-seeded, thin-walled, surrounded by the inner epicalyx, and this in turn by the hardened, 4-lobed, capitate-glandular outer epicalyx, the tips of which are hooked; fruit with epicalyces breaking off from the top of the pedicel as a diaspore. Seed oblong, subterete, acutish towards both ends, smooth but for two faint, longitudinal ridges; albumen plentiful; embryo scarcely shorter than the seed.
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Herbs, perennial, erect. Taproots fusiform. Rhizomes horizontal. Basal leaves dense, rosulate; leaf blade serrate or pinnatifid; cauline leaves decussate, otherwise similar. Inflorescence paniculiform, flowers in remote, terminal, simple or compound dichasia, all parts densely white villous and glandular hairy; bracts linear; involucels 2, urceolate, outer involucel 4-lobed, outer surface glandular pubescent, inner involucel 8-ribbed. Flowers nearly actinomorphic. Calyx reduced, 4-lobed. Corolla tubular-funnelform, 5-lobed; lobes subequal, imbricate in bud. Stamens 4, equal in length, alternate with corolla lobes; anthers introrse, versatile. Style solitary; stigma capitate. Achenes enveloped in urceolate involucels. Seeds subglobose, acute at both ends, smooth, with 2 obscure angles; endosperm copious; embryo small.
A decidedly microtherm genus with a most peculiar, apparently undescribed, 'double' adapta-tion for epizoic dissemination by the (probably sticky) glandular-capitate mucor-like hairs and the hooked tips of the lobes of the outer epicalyx which embrace the fruit and fall off with it from the articulation at the apex of the pedicel. The comparison I made formerly between distribution and dispersal methods in Valeriana and Triplostegia (cf. VAN STEENIS Bull. J.B.B. III 13 1934 p. 257, 403-404 ) loses much of its value by the detection of the above-described dispersal mechanism. 'Hoeckia' was reported to smell of valerianic acid.
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