414 



COMPOSITAE. 



[Vol. III. 



I. Tetragonotheca helianthoides 



Iv. Tetragonotheca. 



(Fig. 3881.) 



Tetragonotheca helianthoides L,. Sp. PI. 903. 



J753- 



Viscidly pubescent; stem branched or sim- 

 ple, i-2^ high. Leaves ovate, ovate-ob- 

 long, or somewhat rhomboid, thin, coarsely 

 and unequally dentate, pinnately veined, 

 acute at the apex, narrowed at the base, 

 sessile, orconnate-perfoliate, 2 / -6 / long, i / -3 / 

 wide; heads usually few, lyi's' broad; in- 

 volucre 4-angled in the bud, its principal 

 bracts broadly ovate, acute; rays 6-10, strong- 

 ly parallel-nerved, 2-3-toothed; corolla-tube 

 villous below; achenes 4-sided, or nearly 

 terete; pappus none. 



In dry soil, Virginia to Florida and Alabama. 

 May-June. Sometimes flowering again in the 

 autumn. 



59. SPILANTHES Jacq. Stirp. Am. 214.//. 126. 1763. 



Annual branching herbs, or some species perennial, with opposite, usually toothed leaves 

 and rather small, long-peduncled discoid and radiate heads, terminal, or in the upper axils, 

 or rays wanting in some species. Involucre campanulate, its bracts in about 2 series, her- 

 baceous, loosely appressed. Receptacle convex or elongated, chaffy, its chaff embracing 

 the disk-achenes and at length falling away with them. Ray-flowers yellow, or white, pis- 

 tillate. Disk-flowers yellow, perfect, their corollas tubular with an expanded 4-5-cleft limb. 

 Anthers truncate at the base. Style-branches of the disk-flowers long, sometimes penicillate 

 at the summit. Ray-achenes 3-sided, or compressed, those of the disk-flowers compressed, 

 margined. Pappus of 1-3 awns, or more. [Greek, spot- or stain-flower, not significant.] 



About 30 species, natives of warm and tropical regions. 



i. Spilanthes repens (Walt.) Michx. 

 Spilanthes. (Fig. 3882.) 



Anthemis repens Walt. Fl. Car. 211. 178S. 

 Spilanthes repens Michx. Fl. Bor. Am. 2: 131. 1S03. 



Perennial, usually rooting at the lower nodes; 

 stem slender, simple or branched, spreading or 

 ascending, &-2 long, pubescent, or nearly 

 glabrous. Leaves ovate to lanceolate, petioled, 

 acute or acuminate at the apex, or the lower 

 obtuse, coarsely toothed, or nearly entire, I/-3' 

 long; heads long-peduncled, solitary at the end 

 of the stem and branches, 6 // -io // broad; bracts 

 of the involucre oblong to oblong-lanceolate, 

 obtuse or acute; rays 8-12, yellow; receptacle 

 narrowly conic; achenes oblong, most of them 

 roughened when mature and hispidulous; pap- 

 pus of 1 or 2 very short awns, or none. 



In moist or wet soil, Missouri to Texas, east to 

 South Carolina and Florida. June-Sept. 



60. RUDBECKIA L,. Sp. PI. 906. 1753. 

 Perennial or biennial (rarely annual), mostly rigid, usually rough or hispid herbs, with 

 alternate undivided lobed or pinnatifid leaves, and large long-peduncled heads of tubular 

 (mostly purple) and radiate (yellow) flowers. Involucre hemispheric, its bracts imbricated 



