COMPOSITE. (COMPOSITE FAMILY.) 247 



1. Z. pauciflora, L. Stem erect, hairy, branching ; leaves obloug- 

 lanceolate ; chaff of the receptacle obtuse ; pappus of the disk flowers 1-awned ; 

 rays red or purple. Waste places, Florida to North Carolina. Introduced. 

 July- Sept. Stem 1 - 2 high. Rays sometimes fading into yellow. 



49. HELIOPSIS, Pers. 



Heads many-flowered ; the ray flowers pistillate ; those of the disk tubular, 

 perfect, 5-toothed. Scales of the involucre in 2-3 rows ; the exterior longer, 

 leafy. Chaff of the conical receptacle lanceolate, partly clasping the 4-angled 

 truncated achenia. Pappus minute or none. Perennial herbs with the 

 habit of Helianthus. Rays yellow. 



1. H. laevis, Pers. Smooth; stem slender, brandling; leaves ovate or 

 ovate-lanceolate, acute or acuminate, sharply serrate, 3-ribbed at the base, on 

 slender petioles ; peduncles elongated ; scales of the involucre obtuse ; rays 

 deciduous; achenia smooth and truncate. Dry open woods, Florida, and 

 northward. August-Sept. Stem 2 -3 high. Leaves 2' -3' long, some- 

 times scabrous. 



2. H. gracilis, Nutt. Stem more slender, often, like the leaves, some- 

 what scabrous; heads smaller; acheuia pubescent, crowned with a minute 

 chaffy pappus ; otherwise like the last. Dry woods in the upper districts. 

 August. 



50. TETRAGONOTHECA, Dill. 



Heads many-flowered ; the ray flowers (6 - 9) pistillate ; those of the disk 

 tubular, 5-toothed, perfect. Involucre double, 4-sided ; the exterior of 4 ovate 

 leaves partly united below ; the interior of about 8 small chaffy scales. Chaff 

 of the conical receptacle lanceolate, acute. Achenia obovoid, nearly terete, 

 truncated. Pappus none. A low hairy and clammy perennial herb, with 

 large sessile or connate, oval or oblong, coarsely toothed leaves, and large 

 solitary heads of yellow flowers, on long peduncles. 



1. T. helianthoides, L. Dry sandy soil, Florida to North Carolina. 

 July. Stems several, stout, 1-1^ high. Leaves 4' -6' long. Head 2' in 

 diameter. 



51. SPILANTHES, Jacq. 



Heads many-flowered; the ray flowers often wanting. Scales of the in- 

 volucre in 2 rows, appressed, shorter than the disk. Receptacle convex or 

 elongated ; the membranaceous chaff embracing the flowers. Achenia of the 

 disk compressed, mostly ciliate on the margins, naked at the apex, or with 

 1-3 bristly awns ; those of the rays 3-angled. Chiefly annual acrid herbs, 

 with opposite undivided leaves, and solitary heads of yellow flowers on long 

 peduncles. 



1. S. repens, Michx. Stem branching, smooth or pubescent, decumbent 

 and rooting at the base ; leaves ovate-lanceolate or lanceolate, slightlv or 

 coarsely serrate, narrowed into a petiole; heads small, ovoid, becoming 

 oblong-conical ; achenia awuless or minutely 1 -2-awned ; ravs 12. Muddy 

 oauks. Sept. - Oct. 2/ Stem 6' - 2 long. 



