30 NORTH AMERICAN FLORA [VOLUME 32 
calyx-lobes or longer, the lobes oblong or ovate, obtuse or acute, slightly shorter than the tube; 
anthers included; capsule subdidymous, 3.5-4.5 mm. wide, half inferior, glabrous; seeds sub- 
globose, about 0.8 mm. in diameter, crateriform, yellowish-brown, scrobiculate. 
TYPE LOCALITY: James Island, South Carolina. 
DISTRIBUTION: Dry soil, Virginia to Florida, Texas, and Oklahoma. 
ILLUSTRATIONS: Britt. & Brown, Ill. Fl. f. 3395; ed. 2. f. 3914; Rob. & Fern. Man. f. 913. 
14. Houstonia caerulea L. Sp. Pl. 105. 1753. 
Anonymos erecta Walt. Fl. Car. 86. 1788. 
Poiretia erecta J. F. Gmel. Syst. 2: 263. 1791. 
Houstonia Linnaei Michx. Fl. Bor. Am. 1: 84. 1803. 
Houstonia Linnaei elatior Michx. Fl. Bor. Am. 1: 85. 1803. 
Houstonia grandiflora Raf. Ann. Gén. Sci. Phys. 5: 225. 1820. 
Houstonia ciliata Raf. Ann. Gén. Sci. Phys. 5: 226. 1820. 
Hedyotis caerulea Hook. Fl. Bor. Am. 1: 286. 1833. 
Anotis caerulea G. Don, Gen. Hist. 3: 535. 1834. 
Hedyotis gentianoides Endl. Ic. Gen. xi. 1840. 
Anotis gentianoides Walp. Rep. 4: 230. 1847. 
Oldenlandia caerulea A. Gray, Man. ed. 2. 174. 1856. 
Houstonia caerulea f. albiflora Millsp. Fl. W. Va. 375. 1892. 
Houstonia caerulea Faxonorum Pease & Moore, Rhodora 9: 210. 1907. 
Erect perennial, 6-20 cm. high, with long filiform rootstocks, forming dense tufts or mats, 
the stems very slender, angulate, glabrous, the upper internodes longer than the leaves; stip- 
ules minute, whitish, naked; leaves crowded at the base of the stem, remote above, the petioles 
sometimes as long as the blades, the uppermost leaves usually subsessile, the blades mostly 
spatulate or obovate, sometimes oval, rounded-ovate, suborbicular, or elliptic, 4-12 mm. long, 
1—6 mm. wide, rounded to acute at the apex, obtuse to attenuate at the base, thin, hirsutulous 
or glabrous on the upper surface, glabrous beneath, usually ciliolate; flowers few, terminal and 
axillary, the pedicels slender, erect, 1.5—7 cm. long; hypanthium about 1 mm. long, glabrous; 
calyx-lobes linear-oblong, acute, twice as long as the hypanthium or longer, in fruit usually 
much exceeding the capsule; corolla salverform, violet, blue, or white, with a yellow eye, 8-15 
mim. long, the tube slender or very thick, three times as long as the calyx-lobes or longer, the 
lobes oblong to oval, rounded to acute at the apex, equaling or shorter than the tube; anthers 
included; capsule subdidymous, about 3 mm. broad, almost half inferior, glabrous; seeds sub- 
globose-crateriform, 0.8 mm. in diameter, dark yellowish-brown, scrobiculate. 
TYPE LOCALITY: Virginia. 
a DISTRIBUTION: Fields and hillsides, Nova Scotia to Wisconsin, Missouri, Alabama, and 
eorgia. 
ILLUSTRATIONS: Britt. & Brown, Ill. Fl. f. 3393; ed. 2. f. 3912; Bot. Mag. pl. 370, 2822 (as H. 
serpyllifolia); W. Barton, Fl. N. Am. pl. 34, f. 1; Endl. Ic. Gen. pl. 89; Meehan, Nat. FI. 1: pl. 25; 
Moris. Hist. 15, pl. 4, f. 1; Pluk. Alm. pl. 97, f. 9; Lam. Tab. Encye. pl. 79; Bot. Cab. pl. 950. 
15. Houstonia serpyllifolia Michx. Fl. Bor. Am. 1: 85. 1803. 
Houstonia tenella Pursh, Fl. Am. Sept. 106. 1814. 
Anotis serpyllifolia G. Don, Gen. Hist. 3: 535. 1834. 
Anotis tenella G. Don, Gen. Hist. 3: 535. 1834. 
Hedyotis serpyllifolia T. & G. Fl. N. Am. 2: 39. 1841. 
Oldenlandia serpyllifolia A. Gray, Man. ed. 2. 174. 1856. 
Prostrate perennial, with filiform rootstocks, the stems very slender, prostrate, rooting 
at the nodes, forming dense mats, the flowering stems ascending, the branches angulate, 
glabrous; stipules minute, scarious, naked or sparsely ciliolate; leaves petiolate, the petioles 
slender, usually half as long as the blades or longer, the blades mostly suborbicular, sometimes 
ovate or oval, 5 mm. long and broad or smaller, rounded or obtuse at the apex, usually rounded 
at the base, rarely cuneate, glabrous, or minutely scaberulous on the upper surface, usually 
ciliolate; flowers axillary and terminal, the slender pedicels 1.5—4 ecm. long, erect or ascending; 
hypanthium about 1 mm. long; calyx-lobes linear-oblong, acute or obtuse, twice as long as the 
hypanthium, in fruit scarcely exceeding the capsule; corolla salverform, 10-12 mm. long, the 
tube usually twice as long as the calyx-lobes, the lobes oval, usually obtuse or rounded at the 
apex, commonly equaling or exceeding the tube; anthers included; capsule subdidymous, 2.5— 
3.5 mm. broad, one third inferior, glabrous; seeds subglobose-crateriform, 0.8 mm. in diameter, 
black, coarsely scrobiculate. 
