COMPOSITjE. (composite FAMILT.) 221 



7. C. delpIliHifdIia, Lam. Glabrotis or nearly so ; leaves divided in- 

 to 3 sessile leaflets which are 2 - 5-parted, their divisions lance-linear (1"- 3" broad), 

 rather rigid; disk brownish. — Pine woods, Virginia and southward. July. 



8. C. verticillata, L. Glabrons; leaves divided into 3 sessile leaflets 

 which are 1 - 2-pinnately parted into Ttarrowly linear or fllifarm divisions. — Damp 

 soil, from Maryland and Michigan southward. Also in gardens. July - Sept. 



9. C. palmata, Nntt. Nearly smooth, simple; leaves broadly wedge- 

 shaped, deeply S-cleft, rigid ; the lobes broadly linear, entire, or the middle one 3- 

 lobed. — Prairies, Michigan to Wisconsin, and southwestward. July. 



# * * # Achenia nearly orbicular, broadly winged, incurved, furnished with a caUous 

 tubercle on the inside at the top and bottom, crowned with 2 small chaff-like dentica- 

 late teeth : outer involucre about the length of the inner : rays large, coarsely 3-5- 

 ioothed: leaves opposite or the uppermost alternate ; heads on long naked peduncles. 



10. C aiiriculata, Linn. Pubescent or glabrous; stems l°-4°high, 

 branching, sometimes with runners ; leaves mostly petioled, the upper oblong or oval- 

 lanceolate, entire ; the lowir oval or roundish, some of them variously 3 - i-lobed or 

 divided ; scales of the outer involucre oblong-linear or lanceolate. Ij. — Bich 

 woods and banks, Virginia, Kentucky, and southward. June - Sept. 



11. C. lanceolata, L. Smooth or hairy (10-2°high); stems short, 

 tufted, branched only at the base ; leaves all entire, lanceolate, sessile, the lowest 

 oblanceolate or spatulate, tapering into^ petioles ; scales of the outer involucre 

 ovate-lanceolate. Ij, — Eich or damp soil, Michigan to Virginia, Kentucky, 

 and southward. July. Also cultivated. — Heads showy : rays 1' long. 



§ 2. Branches of the style truncate ; rays rose-cohr : disk yellow. 



12. C. r6sea, Nutt. (Rose-floweeed Coreopsis.) Stem branching, 

 leafy, smooth (6' - 20' high) ; leaves opposite, linear, entire ; heads small, some- 

 what corymbed, on short peduncles ; outer involucre very short ; rays 3-toothed ; 

 achenia oblong, wingless ; pappus an obscure crown-like border. 1|. — Sandy 

 and grassy swamps, Plymouth, Massachusetts, to New Jersey, and southward : 

 rare. Aug. 



C. hnot6bia, Nutt., a native of the plains beyond the Mississippi, with 

 the rays yellow above, and brown-purple towards the base, is now everywhere 

 common in gardens. 



♦ 



42. BIDEIVS, L. Bub-Mabigold. 



Heads many-flowered ; the rays when present 3-8, neutral. Involucre dou- 

 ble, the outer commonly large and foliaceous. Receptacle flattish, the chaff 

 deciduous with the fruit. Achenia flattened parallel with the scales of the invo- 

 lucre, or slender and 4-sided, crowned with 2 or more rigid and persistent aivns 

 which are downwardly barbed. — Annual or perennial herbs, with opposite vari- 

 ous leaves, and mostly yellow flowers. (Latin bidens, two-toothed.) 

 * Achenia flat, not tapering at the summit. {All annuals'!) 



1. B. frondosa, L. (Commos Begoak-tioks.) Smooth or rather 

 hairy tall (2° -6° high) and branching; leaves 3-5-divided; the leaflets lanceo- 

 19* 



