1. Jacquemontia tamnifolia (L.) Griseb. (tie vine, smallflower morning glory)
Pl. 368 a, b;
Map 1604
Plants annuals,
scrambling and twining. Stems 40–200 cm long, frequently erect when young, but
eventually becoming loosely ascending to prostrate, not angled, sparsely to
densely pubescent with relatively long, loosely spreading hairs. Leaves short-
to long-petiolate. Leaf blades 3–12 cm long, ovate-triangular to elliptic-ovate,
narrowed or tapered to a usually sharply pointed tip, cordate or less commonly
rounded at the base, the margins entire and hairy, the surfaces glabrous or
sparsely hairy. Inflorescences axillary, short- to long-stalked, the flowers
sessile or short-stalked in dense, headlike clusters. Bracts usually numerous
subtending each flower cluster, forming an involucre, each 9–26 mm long,
herbaceous, usually about as long as and slightly obscuring the calyx, often
somewhat overlapping, narrowly lanceolate to elliptic, moderately to densely
long-hairy, especially along the margins, usually persistent at fruiting. Calyx
of free sepals, 7–12 mm long, similar in size and shape, narrowly lanceolate to
linear-triangular, herbaceous, densely pubescent with spreading to loosely
appressed hairs on the outer surface. Corollas 1.2–1.6 cm long, very shallowly
5-lobed, funnelform to nearly bell-shaped, blue. Stamens lacking subtending
scales, not exserted. Ovary 2-locular, with 4 ovules, densely hairy. Style 1,
2-lobed toward the tip, the stigmas thus 2 per flower, oblong to elliptic in
outline, flattened. Fruits 4–7 mm long, ovoid to nearly spherical, 2-locular,
dehiscing longitudinally, the wall separating into usually 4 segments. Seeds
mostly 4, 2.5–3.0 mm long, ovate in outline, somewhat longitudinally angled on
the inner face, the surface tan to brown, pebbled to minutely warty, glabrous.
2n=18. July–October.
Introduced,
uncommon in Butler County and the city of St. Louis (southeastern U.S. west to
Texas, introduced farther north; Mexico, Central America, South America).
Railroads, gardens, and open, disturbed areas.
This species was
first reported for Missouri by Mühlenbach (1979). It is cultivated occasionally
in the Midwest as an ornamental.