Houstonia longifolia var. tenuifolia (Nutt.) Alph. Wood

Houstonia tenuifolia Nutt. Gen. 1: 95. 1818
Hedyotis longifolia tenuifolia T. & G. Fl. N. Am. 2: 40. 1841. Oldenlandia purpurea tenuifolia A. Gray; Chapm. Fl. S. U. S. 181. 1860. Houstonia longifolia tenuifolia Wood, Class-Booked. 1861. 403. 1861. Houstonia purpurea tenuifolia A. Gray, Syn. Fl. N. Am. I 2 : 26. 1884.
Erect perennial, rarely decumbent, the stems solitary or numerous, 1.5-6 dm. long,
usually slender, simple below, branched above, the branches ascending or spreading, obtusely
angled, glabrous, the internodes often much longer than the leaves; stipules scarious, narrowly
or broadly triangular, 2.5 mm. long or shorter, acute or cuspidate, usually glandular-dentate
or laciniate; basal leaves usually wanting at anthesis, earlier forming a rosette, the petioles
stout, half as long as the blades or shorter, the blades oval to oblong-lanceolate, 1-2.5 cm. long,
4-8 mm. wide, rounded to acute at the apex, obtuse or acute at the base, 1 -nerved, scaberulous
or glabrate above, glabrous and often purplish beneath; cauline leaves sessile or nearly so,
linear or oblong-linear, 1.5-4.5 cm. long, 4.5 mm. wide or narrower, obtuse or acute, glabrous;
flowers in very lax leafy cymes, the pedicels filiform, mostly 1-2 cm. long; hypanthium glabrous,
at anthesis less than 1 mm. long; calyx-lobes linear-lanceolate, rarely ciliolate, about twice as
long as the hypanthium, the lobes in fruit equaling or slightly exceeding the capsule; corolla
funnelform, purple, 5-7 mm. long, glabrous outside, the lobes triangular-ovate, obtuse or
acutish, usually less than half as long as the tube, white-villous within; anthers exserted;
capsule subglobose, slightly compressed, 2 mm. long, usually distinctly broader than long,
half inferior, retuse at the apex or rounded, the free portion glabrous; seeds concavo-convex,
oval, about 0.5 mm. long, peltate, coarsely scrobiculate, black.
Type locality: Near the confluence of Pigeon River and the French Broad, Tennessee. Distribution: In dry soil, Virginia to Missouri, and southward to Georgia, Texas, and Nuevo Le6n.