Thelcsperrm. COMPOSIT.E. 301 



§ 4. CoreocXrpus. Akenes nearly of Euleptosyne, but mostly with tuber- 

 culatc rather tliau winged margins, and some of them bearing a pair of sometimes 

 retrorsely hispid awns ; those of the ray-flowers mostly fertile : style-branches of 

 the disk-flowers produced into a subulate appendage : outer involucre of a fe^y 

 small inconspicuous bracts : annuals or suffruticose perennials ; witli branching 

 stems, opposite leaves, and small cymose or paniculate heads on short slender 

 peduncles. — Coreocarpus & Acoma, Benth. Bot. Sulph. 1. c. Coreocarpus, Benth. 

 & Hook. Gen. ii. 384. 



L, Arizonica, Gray. Stems 2 or 3 feet high, and pauiculately branched from a woody 

 base, rigid, slender : leaves 8-5-parted into mostly entire linear acute lobes : heads loosely 

 cymose, 3 or 4 lines long : outer involucre of 1 to 3 small loose bracts; inner of C to 8 ovate 

 ones in two ranks : rays 5 or 6, about 3 lines long : disk-corollas with a bearded ring : akenes 

 narrowly oblong, with faces either smooth or papillose-muriculate, and margins beset with a 

 wing which is wholly dissected into a pectinate tubercular fringe (in the manner of Coreopsis, 

 § Corcoloma), the inner and less fertile or infertile margiidess, some without pappus, others 

 bearing either one or two short and setiform awns, which are either naked or sparingly 

 denticulate, the deuticulations spreading or a few of them recurved. — Proc. Am. Acad, 

 xvii. 218. — Along streams in the Santa Catalina Mountains, Southern Arizona, Zemmon, 

 Prm(]le. 

 "Li. PARTiiENiofDES (Coreocarpus parthcnioidrs, Benth. Bot. Sulph. t. 16), L. hetekocArpa 



(C. keterocarpus, Gray, Proc. Am. Acad. v. 102), and L. dissecta (Acoma disscctiun, Benth. 



L c. t. 17) are species of Lower California, insufficiently known. 



117. THELESPERMA, Less. (®r]\i}, a nipple, o-Trep^a, seed, from 

 the papillosity of some of the akenes.) — Perennial, sometimes annual or suffru- 

 tescent herbs (of the Great Plains, and one on the Pampas of S. Amer.), smooth 

 and glabrous ; with habit of Coreopsis, opposite usually finely dissected leaves, and 

 pedunculate heads ; tlie rays normally golden yellow, disk-flowers yellow, some- 

 times jjurplish or brownish. — Less, in Linn. vi. 511 ; Gray in Kew Jour. Bot. 

 i. 252, & PI. Wright, i. 109. G osmidium, Torr. & Gray, in Nutt. Trans. Am. 

 Phil. Soc. I. c, & Fl. ii. 350. 



* Lobes of the disk-corollas linear or lanceolate, longer than the short campanulate throat : style- 

 appendages witli cuspidate or subulate tips: pajijjus evident: chaff of receptacle falling witli and 

 partly embracing the akenes. 



T. scAEiosioiDES, Lcss., of the Pampas in S. America, closely represents T. gracile, but has 

 more filiform foliage and longer-awncd pappus. 



Cos.MiDiuM BukridgeAnum of the gardens is a hybrid of T. J'ili/ulium and Coreopsis tinc- 

 toria, acquiring its brown-purple rays from the latter. 



T. filifolium, Gray. A foot or two high from an annual or biennial root, loosely branch- 

 ing, leafy : leaves not rigid, bipinnately divided into filiform lobes no wider than the rhachis : 

 bracts of the outer involucre 8, subulate-linear, almost e<pialling or more than half the 

 length of tlie inner, whicii arc connate only to the middle : rays broad, over half-inch long : 

 disk usually purj)le turning brownish : outer akenes becoming coarsely papillose on the back ; 

 the stout triangular-subulate pappus-.scales not longer than the width of the akene. — Kew 

 Jour. Bot. i. 252, & PI. Wriglit. i. 109. Coreopsis trijida, Lam. 111. t. 704- ; Poir. Suppl. ii. 

 353, e.\ tab. C.Jllifolia, Hook. Bot. Mag. t. 3505. Cosmidium Jilifolium, Torr. & Gray, PI. 

 ii. 350. — Dry uplands and plains, Arkansas to Texas. 



T. ambiguum, Gray. A foot high, perennial and spreading by creeping rootstocks, rather 

 rigid, usually more naked above or with longer peduncles: caulinc leaves less compound; 

 tlie lobes from filiform to narrowly linear ; bracts of inner involucre connate to or above the 

 miihlle : rays rarely wanting; otherwise as the preceding. — Proc. Am. Acad. xix. 16. 

 T. Jilifolium, Gr.ay, I'l. Wright, i. 109, & ii. 90, chiefly. — Plains and hills, W. Texas to New 

 Mexico, Colorado, and Montana. 



