COMPOSITE FAMILY. 249 



44. BIDENS, BUR MARIGOLD, BEGGAR'S TICKS, PITCHFORKS. 



(Latin: two-toothed, from the usually 2 awns of the pappus.) Our 

 species or (g). The akenes adhere to the dress or to the fleece of 

 animals by their barbed awns. (p. 227.) 



* Akenes broad and flat, with bristly ciliate margins. 

 <- Coarse and very homely weeds, commonly without any rays. 



B. frond6sa, Linn. COMMON BEGGAR'S TICKS. Coarse weed in low or 

 manured grounds ; 2-6 high, branched, with pinnate leaves of 3-5 

 broad lanceolate, coarsely toothed leaflets, outer involucre much longer 

 than the head, and wedge-obovate akenes ciliate with upturned bristles, 

 and 2-awned. 



B. connata, Muhl. Smooth, l-2 high, with simple lanceolate and 

 taper-pointed leaves, or the lower 3-divided and decurrent on the petiole ; 

 smaller heads ; narrow wedge-shaped akenes, minutely and downwardly 

 ciliate and bearing about 3 awns. Low grounds. 



*- -t- Low smooth herbs, with showy golden rays 1' long. 



B. chrysanthemoldes, Michx. Shallow water or wet places ; 6'-30' 

 high, with simple, lanceolate, sessile, serrate leaves, outer involucre 

 shorter than the rays, and wedge-shaped akenes with almost prickly, 

 downwardly barbed margins and 2-4 awns. 



* * Akenes linear or needle-shaped. 



B. B^ckii, Torr. Immersed in water, N. and W., the single, short- 

 peduncled heads rising above the surface, and with showy rays ; leaves 

 cut into very numerous, fine, hair-like divisions ; awns of the stout akenes 

 4-6, barbed near the tip. 



B. bipinnata, Linn. l-3 high, branched, with 1-3-pinnately parted, 

 petioled leaves ; ovate-lanceolate leaflets ; small heads ; short, pale-yellow 

 rays, and slender akenes with 3-4 barbed awns. Dry soil, R. I., S. 

 and W. 



45. COSMOS. (Greek: an ornament.} Tall plants with handsome, 

 fine, foliage and very late flowers. Cult. (p. 227.) 



C. bipinnatus, Cav. Leaves pinnately divided into narrowly linear or 

 almost filiform lobes ; outer involucral scales ovate-lanceolate and acumi- 

 nate ; rays l'-2' long, rose-color. Mexico. 



C. tenuifo/ius, Lindl. Rather lower, the foliage still more finely cut ; 

 outer scales less acuminate ; rays rich or dark purple. Mexico. 



46. HELENIUM, SNEEZEWEED. (Old Greek name.) (p. 226.) 



H. autumnale, Linn. The commonest species, wild in low grounds ; 

 l-4 high, with lanceolate, toothed leaves, their base often decurrent on 

 the stem, and a corymb of showy yellow-flowered heads, the rays often 

 drooping, in autumn. 2Z 



47. GAILLARDIA. (Gaillard de Merentonneau, a French botanist.) 

 (p. 226.) 



G. lanceolata, Michx. Leaves narrow (mostly entire), lanceolate; 

 rays commonly small and few, yellow, and purple disk flowers. S. Car., 

 W. and S. (2) 2Z 



G. pulch^lla, Foug. Wild from La., W., and cult, for ornament (one 

 form called G. P*CTA), has broader leaves, some of them cut-toothed or 

 lobed, and showy heads with the large rays mostly brownish crimson- 

 purple with yellow tips, d) 



