1106 RUBIACEAE 
1. PINCKNEYA Michx. 
Shrubs or small trees, with terete branches. Leaves opposite: blades entire : stipules 
narrow, caducous. Flowers showy, perfect, in terminal or axillary corymbose cymes. 
Hypanthium dilated upward. Sepals 5, one or two of them, at least in the outer flowers, 
transformed into pinkish leaf-like members. Corolla greenish, mottled with brown or 
purple: tube slightly dilated at the throat, pubescent within: lobes 5, obtuse, valvate, 
pubescent within. Stamens 5, adnate to the base of the corolla-tube. Disk annular. 
Ovary 2-celled. Styles somewhat club-shaped, 2-lobed at the apex. Ovules numerous in 
each cavity, horizontal. Capsule subglobose, 2-celled, opening loculicidally by 2 longi- 
tudinal valves, each valve septicidally splitting to the middle. Seeds numerous, minute, 
flattened, in 2 rows. Testa loosely reticulated. Endosperm fleshy. Embryo elongated. 
1. Pinckneya pübens Michx. A shrub or small tree sometimes 6 m. tall, the foli- 
age more or less densely tomentulose when young. Leaf-blades oblong, ovate or oval, 5-20 
em. long, acute or abruptly acuminate, acute or truncate at the base: petioles 1-2 cm. long: 
enlarged sepals similar to the leaves, but smaller and light pink: sepals linear to nar- 
rowly linear-lanceolate, 1-1.5 em. long, tomentulose, acute: corolla greenish, mottled with 
brown or purple; tube 1.5-2 cm. long; lobes linear or broadened upward, as long as the 
tube or shorter: capsules subglobose, nearly 2 cm. in diameter. 
In pine-land swamps or hammocks, South Carolina to Florida. Spring and summer. 
2. OLDENLÁNDIA L. 
Annual or perennial herbs or shrubby plants, with erect or diffusely forked stems. 
Leaves opposite: blades usually narrow with narrow stipules. Flowers in terminal or 
axillary panicles. Hypanthium turbinate or subglobose. Sepals 4. Corollas white or 
pink, varying from rotate to funnelform: tube usually glabrous in the throat: limb with 
4, or rarely 5, valvate lobes. Stamens 4, or rarely 5: filaments adnate up to the throat of 
the corolla-tube. Ovary 2-celled : styles united below, slender. Ovules usually several 
in each cavity. Capsule membranous, terete or angled, variable in shape, not extend- 
ing beyond the hypanthium, opening loculicidally. Seeds often angled. Testa smooth or 
granular. Endosperm fleshy. Embryo clavate. 
Annual plants: sepals acute, ciliate. ; 
Stems hirsute: leaf-blades short-petioled. 1. O. uniflora. 
Stems glabrous: leaf-blades sessile. 2. O. fasciculata. 
Perennial plants : sepals acuminate, not ciliate. 3. O. Bosci. 
1. Oldenlandia unifldra L. Annual, pubescent. Stems erect or decumbent, simple 
or branched at the base, the branches 1-4 dm. long: leaf-blades ovate to oblong, 0.5-2.5 
em. long, acute: flowers solitary or clustered in the axils: sepals ovate or oblong-ovate, 
acute, about as long as the hypanthium or longer at maturity : capsules globular, 1-1.5 mm. 
in diameter. 
In moist sandy soil, New York to Florida and Texas. Spring to fall. 
2. Oldenlandia fasciculata (Bertol.) Small. Annual, glabrous or nearly so. 
Stems erect or diffusely branched, somewhat lustrous: leaf-blades oblong to lanceolate or 
ovate-lanceolate, 0.5-2 cm. long, acute or somewhat acuminate, sessile: clusters loosely 
2-5-flowered : sepals ovate to ovate-lanceolate: capsules 1.5-2 mm. in diameter, inclu 
inthe hypanthium. [Hedyotis fasciculata Bertol. O. littoralis C. Mohr. J 
On sandy beaches, Florida to Mississippi. Summer and fall. i 
3. Oldenlandia Bóscii (DC.) Chapm. Perennial, glabrous. Stems commonly dif- 
fusely branched, 1-3 dm. long : leaf-blades linear or attenuate to the base, 1-2 cm. long- 
acute at the apex : clusters few-flowered, or flowers sometimes solitary: sepals triangular- 
subulate, shorter than the hypanthium : corolla-lobes triangular or ovate-triangular, acute : 
capsule sabout 2 mm. in diameter. 
In wet sandy soil, South Carolina and Arkansas to Florida and Texas. Spring to fall. 
3. HOUSTONIA L. 
Annual or perennial herbs, with creeping or upright stems. Leaves opposite : blades 
entire, often ciliate. Flowers perfect, often dimorphous, solitary, or in corymbose cymes. 
Hypanthium subglobose or obovoid. Sepals 4, separated. Corolla white, blue or purple, 
funnelform or salver-shaped : tube with a glabrous or pubescent throat: lobes 4, valvate. 
Stamens 4 : filaments adnate to the tube or throat of the corolla. Ovary sessile, 2-celled : 
