Herbs biennial, usually hispid or bristly, rarely pubescent. Roots terete. Stems erect to ascending, frequently branched from base, sometimes very short. Leaves alternate, margin entire, rarely with obscure teeth; lateral veins few, not conspicuous. Cymes short, crowded, rarely elongated, becoming spiciform or racemelike, sometimes 1-flowered at a branching point opposite a leaf; bracts obscure. Calyx 5-parted, slightly enlarged in fruit, subtending nutlets. Corolla blue or white, low salverform; throat 5-appendaged; appendages opposite lobes; limb 5-lobed, spreading horizontally. Stamens included. Ovary 4-parted. Style included; stigma compressed globose. Gynobase nearly flat or low fastigiate. Nutlets ovoid or long turbinate, slightly dorsiventrally, rarely slightly bilaterally compressed, or abaxial and adaxial surfaces extended and becoming long turbinate, usually tuberculate, glabrous or short pubescent, rarely with glochids, abaxially usually with an aperture, aperture margin 1-(or 2)-layered; attachment scar extending from base to apex adaxially.
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