Bidtns. COMPOSITE. . 295 



lineatis," &c., is taken) & Vaill, ; TTalt. Car. 215; name best not restored. Diodonta mitls 

 aiirea, & leptophylla, Xutt. Trans. Am. Phi!. Sue. 1. c. 360. — Wet i^round, X'ir^inia to Florida! 

 The original C. aurea is a form with some of tlie upper leaves lanceolate "and entire, low- 

 ermost of 3 leaflets. Extreme forms are : var. subinlt'/nt, Torr & Ciai , with aU or most of 

 the leaves undivided and lauceohite {C. arguta, Pursh, Fl, :,67, & C'.'amhhua, Xutt. Jour. 

 Acad. Philad. vii. T5) ; var. leptophijUa, Torr. & Gray, 1. c, with leaves or their few divisions 

 elongated linear, only a line or two wide (Dtodonta lejitophyUa, Xutt. Trans. Am. Phil. Sue 

 1. c), a brackish coast form; and var. incisa, Torr. & Gray, 1. c, with nearly all the leaves 

 3-7-divided and the divisions incised or coarsely serrate (C. mifis, Jlicli.x. Fl. ii. l:j8, & the 

 C. coronata of herb. Linn.), the form which approaches or passes into the following. 



^■C. trichosperma, JIichx. Glabrous or nearly so, a foot or two (rarely 3 to 5) high: 

 leaves almost all 3-5-diviiled into lanceolate coarsely serrate or pinnately incised divisions : 

 rays oval-obovate, two-thirds to three-fourths inch long : akenes narrowly cuneate-oblong, 

 sparsely hairy or glabrate, about 4 lines long and barely a line wide, or the outer somewhat 

 broader and shorter, bearing a pair of strong subtilate pointed erect teeth, commonlv equal 

 in length to the breadth of the summit of the akene. — Fl. ii. 130 ; Torr. & Gray, Fl. ii. 340. 

 C. aurc-u, Lindl. Bot. lieg. t. 1228. Diodonta coronata, Xutt. 1. c. — Wet ground, coast of 

 Mass. to Virginia and N. E. Georgia. Also shore of L. Erie to Illinois; where is a 



Var. tenuiloba. Tall, much branched : divisions of the leaves from narrowly lanceo- 

 late to linear ; akenes smaller (outer barely 3 lines long), and with shorter somewhat spread- 

 ing teeth : approaching C. aurea. — Peat bogs, Indiana and Illinois, Vasei;, Stewart, &c. 

 •)— ■)— Heads radiate : rays golden yellow, sometimes inch long : akenes obovate, very flat, with 

 very thin margins hispid-ciliate: leaver all .3-7-<Uvided or parted; the divisions serrate, incised, 

 or some again cleft: herbage somewhat pubescent or glabrous. (Hybrids of these with Bidens 

 fronaosa or others are not uncommon.) 



•■C. aristosa, JIichx. Stem l to 3 feet high : divisions of the leaves lanceolate, acuminate .■ 

 bracts of the outer involucre 8 to 10, barely ciliate, not surpassing the inner: akene with a 

 pair of slender upwardly scabrous awns of 'ts own length, or these rarely wanting. — Fl. 

 ii. 140; Torr. & Gray, 1. c. ; Houlc. f. Bot. Alajr. t. 6462. C. ariilata, Willd. S|iec. iii. 2253. 

 Diodonta aristoxa, X'utt. I.e. — Swamps, ."Michigan to Iowa, Missouri and "W. Louisiana: 

 Southwestward with the var. nnitica (the awns wanting), there disposed to pass into the 

 next. 



kC. involuorata, Xutt. Heads rather larger : bracts of the outer involucre i2 to 20, mostly- 

 surpassing the inner, slender, hispid on the back and margins : akenes with :; t-bort acute 

 teeth. — Jour. Acad. Philad. vii. 74 ; Torr. & Gray, 1 c. Diodonta involucrata, Xutt. Trans. 

 Am. Phil. Soc. 1. c. — W. Illinois to Kansas and Texas. 



4^ -t^ -4— Heads without rays, or rarely a rudimentary one, short-pedunculate; disk dull yellow : 

 outer involucre of 3 to 5 irregular foliaceous bracts, some or most of them surpassing the head; 

 herbage glabrous or nearly so: leaves slender-peti )led. 



" C. bidentoid.es, Xutt. Rather stout, 1 to 4 feet high, with ascending branches : leaves 

 tmdivided, lanceolate, acuminate, serrate, tapering at base into the long petiole : heads ob- 

 long, half to three-fourths inch long, and outer involucral bracts sometimes inch and a half 

 long, resembling uppermost leaves ; bracts of inner involucre with somewhat petaloid mar- 

 gins and tips ■ akenes cnneate-linear, 4 or 5 lines long, more or less exceeding the two setif orm 

 upwardly bispidulous awns, rarely vestiges of a%vns from lateral nerves. — Torr & Gray, Fl. 

 ii. 339. Diodonta (Heterodonta) b>dentoides,'SuU Trans Am. Phil. Soc. vii 361. — JIuddy 

 shores of Delaware Eiver and Bay, from above Philadelphia . first coll by Nuilall. 



*C. discoidea, Tore. & Ghat, 1. c. Slender, with widely spreading branches, a foot or two 

 high : leaves membranaceous, irregularly serrate ; uppermost undivided and rhomboid- 

 lanceolate ; lower divided into 3 sessile or petiolulate leaflets : heads campanulate, a quarter- 

 inch high : akenes narrowly cuneiform, 2 or 3 lines long, the two subulate teeth rather than 

 awns mostlv shorter than the width of its summit. — Eiver borders and swamps, Connecticut 

 and X. Xew York to Ohio, Virginia, and Texas. 



113. BIDENS, Toum. Bur-3Iaeigold, (Lat. JiWews, with t\vo teeth or 

 prongs: name from the adjective, i. e. planta lidens, therefore feminine.) — Herbs, 

 of wide distribution, chiefly American; with opposite either simple or compound 



