Coreopsis. COMPOSITuE. 349 



Sandy or grassy swamps, from Plymouth, Massachusetts, Mr. OaA'cs / 

 Mr. Russell! Nantucket, iVir. T.A.Green! and Rhode Island, Pro/". S«i?e?/.' 

 to New .Tersey ! and Georgia. July-Aug. — H Plant slender, 8-15 inches 

 high. Heads small. Appendages of the style (yellow) slightly capitate and 

 truncate. 



C. trifida (Lam. ill. t. 704) is of unknown ori^n, and is unlike any North Ameri- 

 can species. 



C. flexicanlis (Raf ) : " stem simple, flexuous ; leaves linear, thickened, the lower 

 ones attenuated, the tipper ones opposite; flowers terminal, ci-own-flovvpred : flos- 

 cules 1-fid," Raf. in mad. repos. {Jiex. C) 5. p. 361, (South New Jersey) is not likely 

 to be identified. 



C. aspera (Pursh) : " leaves lanceolate-linear, rou2:h ; the upper alternate, the 

 lower opposite; stem one-flowered," Pi;/"5/(, y?. 2. p. 570, is said to have been de- 

 scribed from a Maryland specimen in the Banksian herbarium; where, however, we 

 did not recognize the species. 



C. acuta {V\ws\\,\. c): "leaves ovate-lanceolate, acute, denticulate, somewhat 

 hairy, alternate; flowers coiymbose-paniculate," which we were also unable to iden- 

 tify in the Banksian herbarium, is perliaps Acdnomeris squarrosa. 



C. alata (Pursh, 1. c.) is doubtless Verbesina Siegesbeckia. 



Peramibus, Raf. — Under this name Rafinesque founded a genus in his Annals of 

 Nature (1820), which is chiefly characterized by having triangular naked achenia, 

 and the scales of the involucre alternately longer and shorter in a single series. It 

 was established on a Kentuckian plant, P. hirtus, which is Rudbeckia triloba! To 

 the genus he referred, somewhat doubtfully, several species which he had not seen, 

 viz: his own Coreopsis scabrd of liie Ftorula Ludoiticiana, the C. acuta, Piirs/i, and 

 the C. palmata, rosea and nudata of Nuttall, none of which accord with his 

 charactei". 



Div. 4. BidentidejE, Less., DC. — Rays neutral, ligulate, or some- 

 times wanting. Achenia obcompressed, or often tetragonal or terete, and 

 rostrate. Pappus of 2-4 (rarely 5-6) retrorsely barbed or scabrous hispid 



awns. 



y 



102. COSMOS. Cav. ic. 1. j^. 9, t. 14 S^- 79 ; DC. prodr. 5. p. 606. 



Heads many-flowered; the ray-flowers (about 8) neutral; those of the 

 disk tubular, perfect. Involucre double, each of 8-10 acute or acuminate 

 scales, more or less united. Receptacle flat; the chaff membranaceous, at- 

 tenuate-acuminate. Corolla of the disk with a slender tube and a 5-toothed 

 limb. Anthers with a scarious cordate appendage. Branches of the style 

 thickened and very hairy or bearded at the summit, terminated by a subu- 

 late cone. Achenia tetragonal or terete, attenuate or rostrate at the summit, 

 sometimes stipitate, crowned with 2-4 retrorsely barbed or scabrous-hispid 

 deciduous awns. — Annual or perennial (mostly Mexican) branching herbs, 

 with opposite 1-2-pinnatifid or divided leaves, the lobes moslly entire. 

 Heads on slender peduncles terminating the branches. Rays jiurple, violet, 

 or rose-color : disk-flowers yellow; the anthers brown. 



1. C. caudatus (H. B. & K.) : glabrous or slightly hairy; leaves petioled, 

 bipinnately parted ; the segments lanceolate, feather-veined, ciliate-scabrous, 



