Description from Flora of China
Herbs perennial or annual, appressed strigose or villous, 20-100 cm tall. Leaves alternate, green, large, thin. Inflorescences rarely solitary, terminal, not branched or paniculate. Fruiting pedicel deflexed. Calyx 5-parted to base or nearly so; lobes enlarged in fruit, vertical to reflexed. Corolla blue, light blue, or light purple, rarely yellow or white, campanulate-rotate to campanulate-tubular; throat with appendages, rarely appendages obscure or absent; lobes 5, imbricate in bud, vertical or divaricate at anthesis. Stamens inserted on corolla, included; anthers orbicular, ovate to oblong. Style and stigma solitary, usually not exceeding nutlets. Gynobase short pyramidal, to 2-3 mm. Nutlets 4, all or some developed, turbinate to ovoid, triangular-ovoid and dorsally compressed, marginal rib with compressed triangular to lanceolate glochids.
About 45 species: mainly in temperate regions of the Northern Hemisphere, and Central and South America; three species in China.
Lian & Wang (Acta Phytotax. Sin. 18: 514-520. 1980; Fl. Reipubl. Popularis Sin. 64(2): 116-151. 1989) argued that the differences between Eritrichium and Hackelia are insufficient to keep
them as separate genera. However, the gynobase in Eritrichium is cushion-shaped, to 1 mm high, while in Hackelia it is distinctly conical and 2-3 mm high. It is likely that other species
from China listed under Eritrichium will need to be transferred to Hackelia in the future.