Annual or possibly perennial herbs, 30–70 cm. or more tall, erect, branched; stems terete, appressed to subpatent white pilose or hispid throughout, some hairs being swollen at base; branches alternate, spreading-ascending. Leaves opposite, subopposite or alternate; upper leaves 30–60(80) x 3–7.5 mm., linear-oblong to narrowly ovate-elliptic, obtuse, shortly apiculate, narrowing into a petiole-like base, entire, appressed-hispid on both surfaces with hairs more patent beneath, margins short hispid-ciliate, 1-nerved; lower leaves up to c. 45 x 20 mm., broadly ovate-elliptic to obovate, obtuse, rounded, narrowed at base, with 1–3 major nerves, median nerve pinnately branched, entire or crenate or bearing 1 or 2 blunt teeth, indumentum as for upper leaves, but becoming scabrid. Inflorescence of long interrupted spikes 12–30 cm. long; flowers alternate or more rarely almost opposite, sessile or if subsessile, pedicels c. 0.5 mm. long, stout, pubescent. Bracts 2.4–4(5) x 1–1.5(2) mm., ovate-lanceotate, acuminate, concave, hispid, ciliate. Bracteoles absent. Calyx 7–8 mm. long, slightly curved, densely almost appressed hispid throughout with short white, frequently callous-based, antrorsely directed hairs, never retrorse, 5-lobed, 10-nerved; lobes 1.5–2(3) mm. long, narrowly lanceolate, subequal, always forwardly directed, never becoming reflexed. Corolla blue to violet or mauve; tube 9–10.5 mm. long, cylindrical, widening at mouth, somewhat curved, densely shaggy-pilose without, throat densely pilose within; limb 8–13 mm. in diam.; lobes 4.5–8 x 2–5 mm., obovate, unequal. Capsule 5–7 x 1–1.5(1.8) mm., oblong in outline, subacuminate at apex, remains of style persistent.
