1116 RUBIACEAE 



2. Diodia tetrigona Walt. Perennial, finely pubescent or glabrate. Stems usually 

 branched at tiie base, the branches spreading or prostrate, 2-10 dm. long, 4-angled : leaf- 

 blades oval, oblong, elliptic or oblong-rhombic, 1-4 cm. long, acute, usually abruptly nar- 

 rowed at the base or cordate, short-petioled : sepals ovate or ovate-lanceolate, 4-5 ram. 

 long, acute : corolla white or pink ; tube slender, 5-7 mm. long ; lobes lanceolate to ob- 

 long, shorter than the tube: capsules 5 mm. long, oval, ribbed. 



In damp sandy soil, North Carolina to Florida and Louisiana. Spring to fall. 



3. Diodia hirsiita Pursh. Perennial, densely hirsute. Stems more or less diffusely 

 branched from the base, the branches 1-8 dm. long, sometimes creeping : leaf-blades linear 

 or narrowly oblong, 1-2.5 cm. long, acute or somewhat acuminate, abruptly narrowed into 

 short petioles or rarely sessile : sepals subulate-lanceolate, 4-5 mm. long : corolla white or 

 pink ; tube narrowly funnelform, 8-10 mm. long ; lobes shorter than the tube, lanceolate 

 or oblong-lanceolate : capsules oblong, 7-9 mm. long, ribbed. 



In sandy soil, Georgia and Florida. Spring and summer. 



4. Diodia tferes Walt. Annual, finely pubescent or hispidulous. Stems terete, or 

 4-angled above, mostly diffusely branched, 1-4 dm. long, the branches usually spreading, 

 rarely creeping : leaf-blades linear or narrowly linear-lanceolate, 1-4 cm. long, acute, 

 abruptly narrowed at the base, nearly sessile : sepals 4, triangular or triangular-lanceolate, 

 1-2 mm. long : corolla white or pinkish, about 6 mm. long ; tube funnelform ; lobes ovate 

 or oblong-ovate, shorter than the tube : capsules obovoid, 2-.3 mm. long. 



In dry or sandy soil, Connecticut to Missouri, Florida, Texas and New Mexico. Summer. 



22. BORRERIA Meyer. 



Annual or perennial caulescent herbs, or shrubby plants. Leaves opposite : blades 

 flat, entire : stipules sheathing. Flowers perfect, solitary in the axils, or in axillary or 

 terminal clustered cymes. Hypanthium obovoid or turbinate. Sepals 2-4, or rarely 5, 

 persistent, sometimes accompanied by small teeth. Corolla white, pink or blue, funnelform 

 or salverform : lobes 4, valvate, spreading. vStamens 4, adnate to the corolla-tube some- 

 times up to its throat. Disk obsolete or cushion-like. Ovary 2-celled : styles wholly or 

 partially united. Ovules solitary in each cavity, amphitropous. Fruit leathery or crus- 

 taceous, the 2 carpels opening along the inner faces. 



Annual : clusters in the axils of the leaves along the stem. 1. B. parviflora. 



Perennial: clusters in a congested head terminating the peduncle-like end of the stem. 



2. B. podocephala. 



1. Borreria parviflora ]\reyer. Annual, glabrous or nearly so. Stems erect or 

 branched at the Ijase, tlie branches spreading, 2-9 dm. long : leaves often clustered ; 

 blades narrowly lanceolate to almost linear or oblong-spatulate, 1-2.5 cm. long, obscurely 

 nerved, sessile: flower-clusters subglobose, 4-8 mm. thick: sepals 4, subulate or lanceo- 

 late-subulate : corolla white, shorter than the sepals ; lobes ovate : fruit ovoid, 1 mm. 

 long, pubescent. 



In waste places or pine woods, Florida. 



2. Borreria podocephala DC. Perennial, glabrous or nearly so. Stems simple and 

 erect or branclied at the base, the branches spreading or decumbent, 0.5-2 dm. long, upper 

 internodes elongated : leaves often clustered ; blades linear, often narrowly so, 1-2.5 cm. 

 long, acute, more or less strongly revolute, sessile : clusters 8-12 mm. in diameter: sepals 

 subulate, about 0.5 mm. long: corolla 2-2.3 mm. long ; tube funnelform, glabrous within ; 

 lobes often 3 : fruit ovoid, 2-3 mm. long, pubescent. 



In sand, peninsular Florida and the Keys, Texas and Mexico. Also in the "West Indies. 



23. SPERMACbCE L. 



Annual or perennial herbs, or low shrubs. Stems usually 4-angled. Leaves oppo- 

 site : blades feather-veined or longitudinally nerved : stipules sheathing. Flowers per- 

 fect, solitary in the axils, or variously disposed. Hypanthium varying from obovoid to 

 turbinate. Sepals 2-4, or 5, often persistent, sometimes accompanied by small teeth. 

 Corolla white, pink or blue, funnelform or salverform : lobes often 4, spreading, valvate. 

 Stamens 4, adnate to the throat of the corolla-tube or lower down. Disk obsolete or 

 cushion-like. Ovary 2-celled : styles wholly or partially united, filiform. Ovules solitary 

 in each cavity, attached to the middle of the septa, amphitropous. Fruit leathery or 

 crustaceous, of two carpels one opening through the ventral face, the other remaining 

 closed. Button-weed. 



