, the only species in its genus, is an annual plant whose foliage is covered in sticky, glandular hairs, and exudes a distinct aroma. Leaves grow at the base and along the stem; they are angled upwards, and deeply lobed, almost to the midvein. Upper stem leaves are stalkless and clasping, while those at the base have short stalks.
The inflorescence is a terminal cluster of flowers, borne at the end of slender, curving pedicels less than one inch long (slightly longer when in fruit). The calyx is formed of five green, lance-shaped sepals, fused only around the base. The corolla is colored yellow or cream, and opens to five short, rounded lobes. The five stamens and the two-lobed style do not project beyond the lobes. The common name whispering bells refers to the rustling noise made when a breeze blows over the dry, papery corolla, after the flowers have withered.