Leaves of janusia gracilis
, a vine, have a covering of white, appressed hairs, on both surfaces. The hairs are attached at their midpoints. Leaves grow at opposite intervals along the slender, freely branching stems, which can be up to ten feet long, usually forming tangled clumps. Leaves have a tooth-like gland at the base.
Flowers are small and delicate-looking; they form in pairs, each flower subtended by a bract. The five yellow petals are about a quarter of an inch long, clawed (narrow) at the base, abruptly wider at the upper end. The upper edges of the petals are slightly uneven. Petals become reddish brown as they wither. Five green sepals project upwards between the bases of the petals, enclosing one style and five stamens, of which only two have anthers. Flowers are replaced by hairy, reddish, two- or three-winged seedpods.