10 C. verticillata L. Glabrous branched lvs. 3-divided, closely sessile, divisions pinnately or bipinnately parted, segments filiform, linear, obtuse; rays acute or (ia cultivation) obtuse and 2 or 3-toothed; ach. obovate, slightly 2-toothed. - Ц Moist places, Md. and Western States. Stem 1 - 3f high. Leaflets apparently verticillate in 6s. Heads with bright yellow rays, near 1' long. Outer scales oblong-linear, obtuse, united at base. June - Aug.

11 C. palmata Nutt. Nearly smooth; st. branched, angled and striate, very leafy to the summit; Ivs. sessile, deeply 3-cleft (to below the middle), rigid, lobes linear, acutish, entire or again cleft; rays obovate-oblong; ach. linear-elliptic, incurved. - Dry prairies, W. States. Stem 1 - 2f high, sometimes much branched. Leaves 1 - 21/2' long, some of them undivided, lobes 2 - 4" wide. Heads 1 or several, with yellow rays. Outer scales linear oblong, obtuse. Jn., Jl. (Calliop-sis, Spreng.)

12 C. tripteria L. Glabrous; st. simple, tall, corymbous at summit; lvs. coriaceous, opposite, petiolate, 3 - 5-divided, divisions linear-lanceolate, entire, acute; hds. small, on shore peduncles, rays obtuse. - A. tall, smooth, elegant species, in dry soils, Southern and Western States, common. Stem 4 - 8f high, slender, terete. Divisions of the leaves 3 - 5' by 3/4 - 1 1/2'. Rays spreading 1/2' long. Outer scales linear, obtuse, spreading, much smaller than the inner. Jl. - Oct. (Chry-sostemma, Less.)

13 C. grandiflora Nutt. Glabrous; st. low, simple or branched; lvs. petiolate, lanceolate, mostly pinnately or ternately divided, segments lance-linear cr linear; hds. solitary, on long peduncles, large; rays 4 to 5-cleft at apex. - Mo. to Ala. and Tex. Plant 1f high. Hds. much like No. 14. Jl. - Sept.

14 C. lanceolata L. St. ascending, often branched below; lower lvs. ob-lanceolaie, petiolate, the upper lanceolate, sessile, all entire, with scabrous margins; hds. solitary, on very long, naked peduncles; rays 4 - 5-toothed at apex; ach. suborbicular, with 2 small teeth. - Ц Native of the Southern States Heads showy. Rays about 8, 1' by 1/3'. Jn. - Aug.†

15 C. auriculata L. Pubescent; lower lvs. roundish-ovate, petiolate, some of them with 2 small, lateral segments at base (auriculate), the upper oblong, nearly or quite sessile; hds. few, on long peduncles; outer scales oblong-linear. - Dry soils, Va., Ky. to Ga. and La. Plant 1 to 3f high, variable. At first (May, Jn.) it has divided lvs. and very long peduncles. Later (Jl., Aug.), it is tall, the lvs. all entire, the lower having perished. Hds. similar to No. 14. May - Aug.

16 C. latifolia Mx. Very glabrous, tall; lvs. thin, opposite, ovate, acuminate, unequally toothed, petiolate, the upper ovate-oblong; hds. small; rays 5 to 6, entire ; outer scales 4 to 5, linear, spreading. - Mts., N. Car. to Ga. Plant with ample lvs. and few large, yellow rays. Aug.

17 C. arguta Ph. Smooth or nearly so; sts. strict, striate-angled; lvs. of the stem simple, petiolate, ovate and ovate-lanceolate, acuminate, mucronate-serrate; hds. few, large, on slender, naked peduncles; outer scales about 8, as long as the inner; rays 9 to 12, 3-cleft; ach. oblong, awns obsolete. - Car. (Pursh), W. Ga., in the upland districts. Differs much from C. aurea. St. 2 to 5f high. Lvs. 1 to 3'long. Rays spreading 1 1/2'. (Root lvs. not seen). May - Jn.

18 C. aurea Ait. Nearly glabrous; lower lvs. pinnately divided, upper ternately. or simple; divisions ovate, lanceolate and lance-linear, acuminate, sharply serrate; outer scales about 8; linear as long as the inner; rays about 8, obtuse; ach. teeth very short. - (D Ditches, etc., N. Car. to Fla. and La. An untidy weed, 2 to 41 high. Hds. small, corymbed. Ach. 2" long. Aug., Oct

19 C. aristosa Mx. Sparingly pubescent; lvs. pinnately 5 to 9-parted, segments lance-linear, incisely serrate or pinnatifid; hds. small, with conspicuous rays; outer invol. of 10 to 12 linear, green scales longer than the inner, villous at base; awns slender, spreading, about as long as the achenium. - (2) Low woods, W. States. St obtusely 4-angled, 2 to 3f high. Lvs. thin, 4 to 6' long, petioles 1/2 to 1'. Rays 8, orange-yellow, expanding 11/2'. (C. involucrata Nutt.)

20 C. trichosperma Mx. St. glabrous, square, dichotomous; lvs. pinnately 5 to 1-parted, briefly petiolate, segm. lanceolate, incised or serrate; scales of the outer invol. ciliate, linear, long as the inner; rays entire, large; ach. narrow-cuneatc, with 2 short, stout awns. - (1) In wet grounds, N. Y., Mass. to Car. A smooth, branching plant, I to 2f high, with a panicle of large, showy, yellow heads. Lvs mostly opposite, thin, the upper 3-cleft, subsessile. Ach. 1/2' long, awns half an long. Jl., Aug. 21 C. discoidea Torr. & Gr. Glabrous, much branched, erect; lvs. ternate, long-petiolate; lfts. ovate-lanceolate, strongly dentate, hds. discoid on slender peduncles ; outer involucre 3 - 5 linear-spatulate, leaf-like bracts; ach. linear-oblong, twice longer than the 2 erect awns which are hispid upwards. - (1) Ohio to La. Stem and branches purplish. Terminal leaflets 3 - 5 by 1/2 - 1 1/2', lateral much smaller. Heads small (3" diam.), about 30-flowered. Jl. - Sept.

58. BI'DENS, L. Burr-Marigold. (Lat. bidens, two-toothed; the achenia have two (or more) barbed teeth.) Involucre double; scales somewhat similar, or the outer foliaceous; rays 4 to 8 (sometimes none), neutral; disk-flowers perfect; receptacle chaffy, flat; pappus of 2 to 4 awns rough backwards; achenia obcomprcssed, obscurely quadrangular. - Lvs. opposite, incised. Fls. yellow.

§ Achenia linear, somewhat 4 angled, 3 to 4 -awed. Rays few or none................

......No. 1

§ Achenia flattened, broadest at top- Rays none or very few...

..Nos. 2 - 4

- RAys about 8, showy, regular.............

..Nos. 5, 6

1 B. bipinnata L. Spanish Needles. Smooth, lvs. bipinnate, lfts. lanceolate, pinnatilid, rays very short or none; outer invol. the length of the inner; ach. slender, elongated. - (1) Grows in waste places Conn., N. Y., west to I11 St. 2 to 4f high, branching, smooth. Lvs. bipinnately dissected, nearly smooth. Hds. of flowers on long peduncles, each with 3 or 4 (or none) obscure, obovate, yellow rays. Jl. - Sept.