202 COMPOSITE FAMILY. 



C. Drummdndii, of Texas, is low and spreading, rather hairy, with leaves 

 of 3 - 7 oval leaflets, or some of them simple, heads on long peduncles, and very 

 broad rays golden yellow with small dark spot at base. 



* * (T) Disk-Jlmvers yellow : rays yellow with a darker and purplish-streaked spot 



near the base : akenes winged and 2-toothed. 



C. COrou^ta, of Texas, is low, with slender-petioled leaves oblong or spatu- 

 late, or some of them 3 - 5-parted, and very long peduncle ; rays broad and 

 handsome. 



* * * !^ Disk-floujers and rays (V long) entirely yellow ; akenes orbicular, much 

 incurved and broadly winged when ripe, crowned with 2 little teeth or scales. • 



C. lanceolkta. Wild W. & S., and cult, in gardens ; 1° -2° high, smooth 

 or sometimes downy, in tufts, with lanceolate or oblanceolate entire leaves 

 mostly crowded at the base, and long slender peduncles : flowers in early 

 summer. 



C. auricul^ta. Wild W. & S., and in some gardens ; taller, sometimes 

 with runners or suckers at base, leafy to near the top ; upper leaves oblong, 

 lower roundish and sometimes auricled at base or with 3-5 lobes or leaflets. 



§ 2. Rays entire or nearly so, oblong or lanceolate : akenes oblong, with a very 

 narrow wing or border, not incurved, and obscurely if at all 2-toolhed at the 

 apex : sccdes of outer involucre narrow and entire : heads rather small, the 

 flowers all yellow. IJ. 



« Low, l°-3° high, leafy to the top: leaves really opposite and sessile, but divided 

 into 3 leaflets, thus seeming to be 6 in a wliorl. Wild chiefly in S. States,, 

 all but theflrst are cult- in gardens. 



C. Senifolia, has seemingly 6 lance-ovate and entire leaflets in a whorl^ 

 (i. e. two, but each 3-divided) smooth or downy. 



C. vertieill^ta, has the pair cut into once or twice pinnate almost thread- 

 shaped divisions, smooth. 



C. delphinifblia, very like the last, but with fewer lance-linear divisions. 



* * Tall, leafy to the top, with evidently opposite petioled leaves. 



C. tripteris. Rich ground W. & S., with simple stems 4° - 9* high, leaves 

 of 3 - .5 lanceolate entire leaflets, corymbed heads, very short outer involucre, 

 and blunt rays. 



§ 3. Rays oval or oblong, golden yellow, slightly notched : akenes wingless, not in- 

 curved, bearing 2 awns or teeth for a pappus : outer involucre conspicuous 

 and resembling leaves : branching plants of wet grounds, with thin leaves 

 mostly of 3 -7 pinnate toothed or cut veiny leaflets ; resembling the next 

 genus, but the awns not downwardly barbed. ® @ 



C. trichosperma. Swamps mostly near the coast, l°-2° high, with 3-7 

 lanceolate or linear cut-toothed leaflets or divisions, numerous heads, and nar- 

 row-oblong or linear wedge-shaped marginless akenes with 2 stout teeth. 



C. aiirea, only S., has upper leaves often simple, lower nearly as in the fore- 

 going, and shorter wedge-obovate akenes with 2 or 4 short chaff-like teeth. 



C. aristbsa, from Illinois S., has more compound leaves with oblong or 

 lanceolate often piiinatifld leaflets, and broad -obovate very flat akenes slightly 

 margined and bristly ciliate, the pappus of 2 long and slender awns, or some- 

 times 3 or 4, or in one variety none at all. 



53. BIDENS, BUR-MARIGOLD, BEGGAR-TICKS. (Latin for two- 

 toothed, from the usually 2 awns of the pappus.) Our species (i) or @ ; 

 fl. summer and autumn. The akenes adhering to the dress or to the fleece 

 of animals by their barbed awns. 



§ 1. Akenes broad and flat, with bristly ciliate margins. 

 * Coarse and very homely weeds, commonly without any rays. 

 B. frond6sa. Common Begg.\r-ticks. Coarse weed in low or manured 

 grounds, 2° - 6° high, branched, with pinnate leaves of 3 - 5 broad lanceolate 



