Part 1, 1918] RUBIACEAE 17 
II. OLDENLANDIEAE. Herbs or rarely shrubs. Leaves usually op- 
posite. Stipules entire, dentate, or setiferous. Flowers 4- or 5-parted; 
corolla-lobes valvate. Ovary 2-celled, the ovules numerous, the placentae 
affixed to the middle of the septum or ascending from the base of the septum. 
Fruit dry, capsular or indehiscent, the seeds few or numerous, small and 
angulate, globose, or peltate, exalate. 
Calyx-lobes 3-dentate at the apex; capsule indehiscent. 9. DENTELLA. 
Calyx-lobes entire; capsule usually dehiscent. 
Flowers 5-parted. 10. PENTODON. 
Flowers 4-parted. 
Seeds angulate. 11. OLDENLANDIA. 
Seeds crateriform or concavo-convex, not angulate. 
Plants with tuberous roots; calyx-lobes alternating with small 
teeth. 12. CLAVENNA. 
Plants never with tuberous roots; calyx-lobes without inter- 
mediate teeth. 
Leaves mostly herbaceous, rarely coriaceous, not imbricate; 
stems herbaceous or suffruticose. ‘ 13. HOUSTONIA. 
Leaves thick-coriaceous, mostly imbricate; stems woody 
throughout. 14. ARCYTOPHYLLUM. 
9. DENTELLA Forst. Char. Gen. 25. 1776. 
Slender- prostrate annual herbs. Leaves small, opposite, petiolate. Stipules small, 
scarious, connate with the petioles. Flowers minute, solitary, axillary and in the forks of the 
branches, sessile or short-pedicellate; hypanthium subglobose; calyx membranaceous, tubular, 
5-lobate, persistent; corolla funnelform, white, the tube pilose within, the limb 5-lobate, the 
lobes 2-3-dentate near the apex, induplicate-valvate. Stamens 5, inserted at the middle of the 
corolla-tube; filaments short; anthers dorsifixed, included, linear. Disk inconspicuous. Ovary 
2-celled; style short, the branches filiform; ovules numerous, inserted on hemispheric placentae 
adnate to the septum. Fruit globose, dry, coriaceo-crustaceous, indehiscent, many-seeded. 
Seeds minute, angulate, the testa punctate; endosperm fleshy; embryo ovoid, bifid. 
Type species, Oldenlandia repens L. 
1. Dentella repens (L.) Forst. Char. Gen. 25. 1776. 
Oldenlandia repens 1,. Mant. 40. 1767. 
Hedyotis repens am. Tab. Encye. 1: 271. 1791. 
Plants much branched, the branches slender, obtusely quadrangular, 0.5-6 dm. long, 
rooting at the nodes, glabrous or obscurely puberulent, the internodes mostly longer than the 
leaves; stipules broadly deltoid or semiorbicular, about 0.5 mm. long, entire, whitish; petioles 
1-2 mm. long; leaf-blades elliptic or obovate-oblong, 4-10 mm. long, 1.5-4 mm. wide, obtuse 
or acute at the apex, obtuse or acute at the base, somewhat succulent, hispidulous or glabrate, 
white-ciliate, 1-nerved; calyx-lobes lance-subulate, attenuate, about 1 mm. long; corolla 3-4 
mm. long; capsule 2.5 mm. in diameter, densely white-hispid or sometimes glabrate; seeds 
brownish-black, 0.3—0.5 mm. in diameter. 
TYPE LOCALITY: India. 
DISTRIBUTION: Tepic and Guerrero, probably adventive; also in India, Australia, Malaysia, 
and Polynesia. 
ILLUSTRATIONS: Forst. Char. Gen. pl. 13; Endl. Atakta pl. 13 (as Lippaya telephioides); Rumph. 
Amb. pl. 170, f. 4; E. & P. Nat. Pfl. 4: f. 8, A. 
10. PENTODON Hochst. Flora 27: 552. 1844. 
Decumbent annual herbs, glabrous, more or less succulent, with quadrangular branched 
stems. Leaves opposite, sessile or petiolate, the blades broad. Stipules short, broad, connate 
with the petioles, entire or dentate. Flowers small, in few-flowered, axillary and terminal, 
pedunculate cymes, white, pedicellate, the pedicels bracteolate at the base; hypanthium turbi- 
nate; calyx 5-dentate, the teeth persistent, remote; corolla funnelform, pilose or glabrous in the 
throat, the limb 5-lobate, the lobes short, obtuse, valvate. Stamens 5, inserted in the throat 
of the corolla; filaments short; anthers dorsifixed, oblong, included. Disk inconspicuous. 
