176 RUBIACE^. (madder FAMILY.) 



and slender ; fruit ovoid, strongly ribbed, cro^vned with the 2 (rarely 4) linear 

 or lanceolate calyx-teeth. (D. tetragona, Walt. D. hirsuta, Pursh.) — Wet 

 places, Florida to North Carolina, and westward. June - Sept. — Stem 1° -4° 

 long. Flowers white or purplish. 



2. D. teres, Walt. Annual ; stem erect, widely branched from the base, 

 terete, bristly or hairy ; leaves linear or lanceolate, acute, rough ; flowers soli- 

 tary or 2 - 3 together ; corolla funnel-shaped ; fruit obovate, even, crowned with 

 the 4 short calyx-teeth. (Spermacoce diodina, Mkhx.) — Drj' sandy soil, Flor- 

 ida to Mississippi, and northward. July -Sept. — Stem 6'- 12' high, some- 

 times prostrate. Flowers purplish. 



5. ERNODEA, Swartz. 



Calyx ovate ; the limb 4 - 6-parted, persistent. Corolla salver-shaped, slender; 

 the lobes 4-6, re volute. Stamens exserted; anthers linear, erect. Style slen- 

 der, longer than the stamens. Fruit obovate, somewhat fleshy, the two separa- 

 ble horny carpels closed. Seeds furrowed on the iimer face. — A somewhat 

 shrubby prostrate and smooth plant, with rigid 3-nerved lanceolate leaves, and 

 solitary sessile axillary flowers. 



1. E. littoralis, Swartz. — South Florida, along the coast. March and 

 April. — Stems straight, rigid, 4-angled, smooth. Branches short, alternate. 

 Leaves sessile, smooth, acute, the upper ones crowded. Flowers sessile in the 

 upper axils, yellow. Fruit roundish. 



6. CEPHALANTHUS, L. Button-Bcsh. 



Calyx obconical, 4-toothed. Corolla tubular, 4-cleft, imbricated in the bud. 

 Stamens 4. Style slender, e.xserted. Stigma capitate. Fruit dry, obconical, 

 separating from the base into 2-4 one-seeded carpels. Seeds pendulous. Albu- 

 men horny. — Aquatic shrubs, with oval or lanceolate leaves, short entire sti- 

 pules, and white flowers collected into a globose long-peduncled head. Recep- 

 tacle hairy. 



1. C. occidentalis, L. Smooth, or the young branches and lower sur- 

 face of the ovate-oblong acute leaves pubescent ; peduncles terminal, and in the 

 upper axils. — Ponds and marshes, Florida, and northward. July and August. 

 — Stem 4° -12° high. Leaves petioled, 3'-5' long, sometimes 3 in a whorl. 

 Heads 1' in diameter. 



7. MITCHELLA, L. 



Flowers by pairs, with their ovaries united. Calyx 4-toothed. Corolla fun- 

 nel-shaped, 4-lobed, hairy within, valvate in the bud. Stamens 4. Style slen- 

 der. Stigmas 4. Fruit composed of two 4-seeded fleshy drupes united, crowned 

 with the 4-toothed calyx. — A smooth creeping evergreen shrub, with small 

 broadly-ovate leaves, minute stipules, and fragrant white terminal flowers. 



1. M. repens, L. — Shady woods, Florida to Mississippi, and northward. 

 March and April — Stem l°-2° long. Leaves 6" -10* long, mostly some- 

 what cordate, shining above, on slender petioles. Corolla ^' long. Fruit red. 



