188 COMPOSITE. 



*** Leaves opposite, divided. 



3. C. trichosperma Mich. : smooth ; stem obtusely 4-angled ; leaves op- 

 posite, on short petioles, pinnate ; leafets 5 7, linear-lanceolate, serrate or 

 incised ; uppermost 3 5-cleft, nearly sessile ; scales of the outer involucre 

 subspatulate, ciliate-serrate ; achenia cuneiform, with 2-hispid teeth. 



Swamps. N. Y. and Mass, to Car. Aug. Oct. .Stem 23 feet high, 

 much branched. Heads in paniculate corymbs, on long slender peduncles; 

 rays about 8, yellow, oblong, obtuse, entire. Tick-seed Sunflower. 



4. C. tripteris Linn. : smooth ; leaves opposite, petiolate ; radical 5-pin- 

 nate ; cauline ternate ; leafets lanceolate, acute, entire, scabrous on the 

 margins ; achenia obovate, naked at the summit. Chrysostemma tripteris 

 Less. D. C. 



Banks of streams. Penn. to Flor. W. to Miss. Aug. Oct. l\..Stem 46 

 feet high. Heads rather small, in a loose terminal corymb, on short peduncles ; 

 rays about 8, yellowish. Three-leaved Coreopsis. 



5. C. verticillata Linn. : smooth ; leaves closely sessile, ternate ; leafets 

 pinnate or bi-pinnate ; segments narrow-linear, obtuse ; achenia obovate- 

 wedgeform, slightly winged, with 2 minute teeth. C. tenuifolia Pursh. 



Wet grounds. Md. to Car. W. to Mich, and Ark. July Sept. 7J. Stem 

 1 3 feet high, slender, somewhat branched. Leaves appearing as if whorled. 

 Heads yellow ; rays long and narrow, rarely obtuse and 2 3-toothed. 



Whorl-leaved Coreopsis. 



34. ACTINOMERIS. Nutt. Actinomeris. 



(From the Greek CLKTIV, a ray, and pepis, a. part; the flower being imperfectly 

 radiate.) 



Heads many-flowered ; ray flowers neutral, few, elongated or 

 sometimes wanting ; those of the disk tubular, perfect. Invo- 

 lucre of 1 3 series ; the scales leafy, acuminate. Receptacle 

 convex, chaffy, the chaff embracing the margin of the achenia. 

 Achenia compressed, obovate, winged, with 2 smoothish per- 

 sistent awns at the summit. 



A. sq^larrosa NuU. : stem erect, pubescent and winged towards the sum- 

 mit ; leaves broad-lanceolate, acute, serrate, scabrous above, pubescent be- 

 neath ; lower often opposite, upper alternate ; involucre in 2 series ; the 

 outer reflexe'd, spreading. Coreopsis aUernifolia Linn. Verbesina Coreop- 

 sis Mich. 



Moist grounds. Yates county, N. Y. to Car. W. to Miss. Aug., Sept. 1\.. 

 Stem 36 feet high, slender, smooth below. Heads small, in a terminal leafy 

 corymbose panicle ; rays few, oblanceolate, yellow ; disk greenish-yellow. 



Squarrose Actinotnen&. 



35. HELIANTHUS. Linn. Sunflower. 

 (From the Greek ^Xb? , the sun, and avQos, a, flower.) 



Heads many -flowered ; ray flowers in one series, ligulate, 

 neutral ; those of the disk tubular, perfect. Involucre imbri- 

 cate in several series ; the scales usually with foliaceous tips. 

 Receptacle flat or convex ; the chaff embracing the compressed 



