1. Evolvulus alsinoides L.

Pl. 366 a, b; Map 1594

Stems 10–45 cm long, prostrate to more commonly erect or ascending, densely pubescent with both shorter, appressed hairs and longer, spreading hairs. Leaf blades 3–20 mm long, lanceolate to oblong-elliptic or elliptic, both surfaces moderately to densely pubescent with relatively long, appressed hairs, the upper surface sometimes only sparsely hairy at maturity. Flowers long-stalked, the stalk longer than the subtending leaf. Sepals 2.0–2.5 mm long, lanceolate, moderately to densely hairy. Corollas 3–4 mm long, blue or rarely white. Fruits 2.5–3.0 mm long, ovoid to nearly globose, glabrous. Seeds 1.5–2.5 mm long, dark brown to black. 2n=22, 26. June–August.

Introduced, known thus far from a single historical collection from St. Louis County (nearly worldwide in tropical and warm-temperate regions). Habitat unknown, but probably railroads or open, disturbed areas.

Various authors have attempted to subdivide this species into a confusing series of varieties, but the morphology of the species is too variable to warrant this action.