Coreopsis. COMPOSITE. 339 



not find sufficient characters to warrant their separation from Coreopsis ; but if this 

 be done, they might with more propriety be joined to Bidens (at least to the broad- 

 fruited section), than erected into a distinct genus, as proposed by Nuttall. 



t Rays none. 



1. C.discoidea: glabrous; stem erect or ascending, diffusely branched; 

 leaves on long petioles, ternately divided ; the divisions ovate-lanceolate, 

 acuminate, mostly petiolulate, coarsely serrate, tlie teeth mucronulate; the 

 uppermost often simple ; heads (small) somewhat paniculate-corymbose at 

 the extremity of the branches, on very short peduncles ; exterior involucre of 

 3-5 foliaceous linear or spatulate bracts, usually much longer than the heads; 

 scales of the inner involucre appressed ; achenia narrowly cuneiform-oblong 

 or linear cuneiform, hairy; tlie awns or teeth erect, upwardly hispid, about 

 the length of the corolla. — Bidens? aff". frondosa, Suilivant! cat, pi. Coiuinh. 

 p. 30 4' 37. 



Wet places and swamps, Columbus, Ohio, Mr. Suilivant .' Feliciana, 

 Louisiana, Dr. Carpenter ! Western Louisiana, Dr. Hale ! Texas, Drum- 

 mond ! Virginia, Mr. Rugel ! July-Sept. — (i) ? Stem 1-2 feet high. 

 Lower leaves sometimes undivided. Mature heads 3 or 4 lines long. Ex- 

 terior involucre sometimes an inch long. Awns sometimes one-fourth or 

 even one-third the length of the achenium, but often very much shorter, even 

 in the same individual. — This plant lias exactly the apjiearance and structure 

 of a Bidens § Platycarpsea, except that the awns are hispid upwardly. 



2. C. bidentoides (Nutt. under Diodonta) : dwarf, diffusely branched, near- 

 ly glabrous; leaves lanceolate-linear, incisely toothed, tapering into a petiole ; 

 exterior involucre of 3 or 4 linear foliaceous scales often longer than the 

 (small) heads; the inner 5-6, membranaceous, with colored (yellow) tips; 

 awns slender, upwardly hispid, much longer than the corolla or the linear- 

 oblong hispid (immature) achenium. — Diodonta (§ ? Heterodonta) bidentoi- 

 des, Nutt. ! in trans. Amer. phil. soc. (n. ser.) 7. p. 361. 



Near Philadelphia, Nuttall! — Founded on a single specimen of somewhat 

 uncertain origin, with the aspect of a dwarf Bidens cernua : the small heads 

 rather few-flowered ; the long awns exserted: the intermediate angles some- 

 times with shorter awns. There appear to be no rays ; what have been so 

 described being the somewhat dilated and exserted yellow summits of the 

 linear-oblong membranaceous chaff'. 



t t Heads radiate. 



3. C. aurea (A.it.) : glabrous or nearly so ; stem striate; lower leaves 1-2- 

 pinnately 3-5-divided; the upper 3-divided or sometimes simple; the divi- 

 sions lanceolate, sharply or incisely serrate; heads paniculate ; scales of the 

 exterior involucre (mostly 8) linear-spatulate, slightly ciliate, not longer than 

 the interior; achenia cuneiform or obovate-cuneiform, nearly glabrous, ciliate 

 towards the summit, crowned with 2 short and triangular concave and .some- 

 what chaffy teeth, or obscurely 4-toothed by the ))roduclion of the interme- 

 diate angles, or with a somewhat coroniform pappus, from the confluence of 

 the very short or obsolete teeth. — Ait. ! Kew. (ed. 1) 3. p. 252. C. coronata, 

 Linn. spec. {ed. 2) 2. p. 1281 .'' (excl. syn. Plum. 8^- Vaill.) ; Walt. ! Car. 

 p. 215. Diodonta aurea & D. rnitis, Nutt. in trans. Amer. phil. soc. 

 (n. ser.) 7. p. 360. 



a. subinf.egra : upper leaves mostly 3-divided, with the lateral divisions 

 short and small ; or the uppermost frequently simple, lanceolate, elongated, 

 petioled, sharply serrate, or entire towards the tapering npax. — C. aurea 

 Ait. ! I. c, not of Lindl. C. arguta, Pursh ! jl. 2. p. 567. C. ambigua, 

 Nutt. ! in jour, acaxl. Philad. 7. p. 75. 



13. leptophylla : cauline leaves pinnately 3-5-divided ; the terminal divi- 



