COMPOSITE. (COMPOSITE FAMILY.) 285 



+- H- Heads somewhat nodding, commonly radiate ; leaves sessile, undivided. 



3. B. c6rnua, L. (SMALLER BUR-MARIGOLD.) Nearly smooth (5'- 3 

 high) ; leaves lanceolate, unequally serrate, scarcely connate ; heads nodding, 

 with or without (light yellow) rays; outer involucre longer than the head; 

 achenes wedge-obovate, 4-awned, the margins downwardly barbed. Wet 

 places, N. Eng. to Va., Mo., Minn., and northward. July -Sept. Rays, 

 if any, smaller than in n, 4, and the outer involucre more leaf-like. (Eu.) 



4. B. chrysanthemoides, Michx. (LARGER BUR-MARIGOLD.) Smooth, 

 erect, or reclining at the base (6' - 2 high) ; leaves lanceolate, tapering at both 

 ends, more or less connate, regularly serrate , outer involucre mostly shorter 

 than the showy golden-yellow (1" long] rays; achenee wedge-shaped, with al- 

 most prickly downwardly barbed margins ; awns 2, 3, or 4. Swamps ; com- 

 mon. Aug - Oct. 



# * Achenes linear, 4-sided, the inner longer and tapering upward. 



5. B. bipinn&ta, L (SPANISH NEEDLES.) Smooth annual, branched ; 

 leaves 1 - 3-pinnately parted, petioled ; leaflets ovate-lanceolate, mostly wedge- 

 shaped at the base ; heads small, on slender peduncles ; outer involucre of linear 

 scales equalling the short pale yellow rays ; achenes 4-grooved and angled, 

 nearly smooth, 3 - 4-awned. Damp soil, R. I. to N. Y., 111., and southward. 



# * * Achenes terete, truncate at both ends, with 3-6 very long awns smooth below. 



6. B. Bckii, Torr. (WATER MARIGOLD.) Aquatic, perhaps perennial, 

 smooth ; stems long and slender ; immersed leaves crowded, capillary, many 

 times dissected, the few emerging ones lanceolate, slightly connate, toothed ; 

 heads single, short-peduncled ; involucre much shorter than the showy (golden 

 yellow) rays ; achenes thickish, smooth (-' long), the stout divergent awns 

 (V long) barbed only toward the apex. Ponds and slow deep streams, Mass, 

 to N. J., Mo., and northward. Aug. - Oct. 



57. THELESPERMA, Less. 



Heads many-flowered ; rays about 8, neutral, or none. Involucre as in Co- 

 reopsis, the inner connate to the middle, scarious-margined. Receptacle flat, 

 the scarious chaff falling with the nearly terete wingless and beakless achenes ; 

 pappus of 2 stout subulate retrorsely hispid awns. Smooth herbs, with oppo- 

 site dissected leaves and pedunculate heads of yellow flowers. (From 6r)\-f), a 

 nipple, and o-Wpjita, seed, on account of the papillose achenes.) 



1. T. grcile, Gray. Perennial, rather rigid, 1-2 high; leaves with 

 narrow or filiform divisions or the upper entire ; outer scales very short ; rays 

 short or usually none ; achenes papillose. Kan., south and westward. 



58. BALDWINIA, Nutt. 



Heads globular, many-flowered, radiate ; the long and narrowly wedge-shaped 

 rays neutral. Involucre short, of many thickish small scales imbricated in 3 or 

 4 rows, the outer obovate and obtuse. Receptacle strongly convex, with deep 

 honeycomb-like cells containing the obconical or oblong silky-villous achenes; 

 pappus of 7 - 9 lance-oblong erect chaffy scales. A perennial herb, smoothish, 

 with slender simple stems (2-3 high), bearing alternate oblanceolate leaves, 



