128 COMPOSITAE 
1. Eclipta alba (L.) Hassk. False Daisy. Fig. 5182. 
Verbesina alba L. Sp. Pl. 902. 1753. 
Verbesina conysoides Trew, Pl. Rar. 8. pl. 8. 1763. 
Eclipta erecta L. Mant. 286. 1771. 
Eclipta alba Hassk. Pl. Jav. Rar. 528. 1848. 
Diffuse or erect, branching, web pone or biennial herbs 2-8 dm. high, eto throughout. Leaves 
opposite, lanceolate to oblong, 2-1 ong, sessile and often clasping, remotely serrulate, tripli- 
nerved ; peduncles mostly solitary in “the forks and in the upper axils, 0. aa cm. long ; heads white- 
rayed, eae 4-8 mm. thick ; involucre SP eriage 3-8 mm. high, the phyllaries subequal, lanceolate 
to broadly ovate, acuminate, strigose, herbaceous above; ray-corollas numerous, not surpassing 
involucre, the ray linear, about 2 mm. long; a 4-toothed, greenish white; achenes ovate- 
oblong, plump, about 2 mm. long, the ray-ac s trigonous, corky-margined and ng bullate, 
hirsutulous on the truncate apex ; pappus a atthe ciliolate crown, often i or 2-too 
Waste places and along streams and irrigation ditches, Lower Sonoran Zone; in central California along the 
lower Sacramento and San Joaquin Rivers and in southern California, eastward neh the Atlantic seaboard and 
southward through Mexico and Central America to South America; introduced in its orthern range in Nebraska 
and Massachusetts. Type locality: Virginia; Surinam. March— Nov. Yerha-de-tago. 
12. BIDENS L. Sp. Pl. 831. 1753. 
Ours annual or perennial herbs, glabrous or somewhat pubescent. Leaves opposite, 
serrate to pinnately wh or r dissected. Heads radiate or discoid, yellow (in ours), soli- 
tary or cymose at apex of stem and branches. Involucre double, the outer of 5-16 Eealiy 
narrow, essentially eee ee sah sehen phyllaries, shorter or longer than the inner ; inner 
of more numerous 2-seriate, equal, membranous, oblong or ovate, several-nerved phyl- 
a 
at, narrow, membranous or subscarious, usually yellow, Jatpienen the achenes. Rays 
neutral, oval or oblong, a a to tridenticulate, shorter o r longer than the involucre 
yellow or yellowish white in ours: disk-flowers perfect, fertile, tubular, 4—5-toothed. 
Anthers pds 28 Wena at base; style- branches with triangular or subulate, hispid tips. 
Achenes linear or fusiform to obovate, not beaked, strongly obcompressed and flat to quad- 
rangular ; papas @ of 2-6 persistent, stiff, retrorsely hispid awns (in ours). [Latin for two- 
toothed, from the bi-aristate achen 
A genus ee perhaps 200 species, nearly aaa the world. Type species, Bidens tripartita L. 
Stems not Laan leaves not divided into filiform or capillary segments; awns 5 mm. long or less. 
Lea rely serrate to subentire; achenes retrose hispid ulous on margin, very narrowly cun 
ase. Yorn ot not over 1. 5 cm — ptacular bracts yellow, conspicuously brown eee achenes 
often what bent, wit tha ong gus on nin face; awns usually 4. . B. cernua. 
Rays 1.5-3 ¢ mtn receptacular tied orange-tipped; achenes eS aight and flat, esa rt facial 
ribs; awns u: tates A . B. lae 
Leaves pinnately 3— Me ted; ciliate or regio 
esse cuneate to Dcaaiy obovate, very flat, 2-4 mm 
Outer phyllaries 5-8, remotely ciliate; wheat sanaltc blackish, narrowly cat 2-3.3 mm. wide. 
. B. frondosa. 
Outer andes Se EN red mde -ciliate; achenes yellowish or olive-brown, Prog howd or 
e€-0 s ata 
Achenes linear to linear-fusiform, more o , 1 mm. wide or less. : = eiaia 
Stems floating; st ged leaves divided into eae or Suc oc pices awns 1.5—2.3 cm. Peat” ae 
6. B. beckii. 
: ae cérnua IL.. Nodding Bur-marigold. Fig. 5183. 
Bidens cernua L, = PL. 8 17 
i Pe uF at = 310. 1762. 
Biden ua elli ibtica Wickes’ , Bull. Torrey Club 26: 417. 1899 
rath beste, B. glaucesens, B. kelloggii, 'B. lonchophylla, B. peiouoplodie Greene, Pittonia 4: 256-267. 1901. 
a al, simple or branched, aioe under 1 m. high, stems stoutish or slender, glabrous or 
sometimes hirsute or hispid. Lea lanceolate to oblong-lanceolate, cm. 
-5 em. thic el 
less, hispidulous-ciliolate, soon refle xed; rays often wanting, when pre ae t about 8, solta: ae fd 
cm. long o Points receptacular r bracts golden-y —— brown-ne apex rarely orange; 
achenes ek cuneate, i 7m ae ng, o - tas what a hi peas Salat ad 1-ribbed on 
eac ce and qu Bins ea te at ie above ae hisvitelen on the margins with usually 
tuber clat-based hairs; awns ( 2\4, Anas “hispid, subequal or "2 sataily shorter, 2-3 mm. long. 
Marshy places, sloughs, and ponds; a native of Europe and Asia occurring in ba stage Capeda: so uth in eastern 
United at Binkee and west to British Columbia Sad New Tesi in the Pacific Sta . - foasac oceasionally in 
Washington and_ Oregon south to Del Norte and Plumas Counties , California, and a ay os and San Fran- 
cisco Counties. Type locality: Europe. June-Oct. Stick-tight. 
