Y. PLANT/E WRIGHTIAN^. 109 



J C. Drummondii, Torr. ^ Gray, I. c, var. foliis caulinis 5 - 7-sectis, segmentis 

 (inf. ssepe trisectis) fere omnibus anguste lanceolatis seu linearibus ; capitulis paullo 

 minoribus ; acheniis maturis dorso tuberculatis marginibus valde incurvis incras- 

 satis. — Western Texas. 



342. Thelesperma (Cosmidium) filifolia, Gray, in Keiv Jour. Bot. 1. ^j. 252. 

 Coreopsis filifolia, Hooh. Bot. 3Iag. t. 3505. Cosmidium filifolium, Torr. Sf Gray, 

 Fl. 2. p. 350. Hills of the Rio Frio, Texas ; June. — The root is truly perennial. 

 — Specimens of T. (Cosmidium) simplicifolia from Saltillo (No. 114 of Gregg's 

 collection) show a few trisected leaves ; so that it may pass into T. filifolia ; but the 

 fruit is not yet known. 



343. T. GRACILIS, Gray, I. c. Cosmidium gracile, Torr. Sf Gray, Fl. 2. ]). 350. 

 Margins of a creek between the Pecos and the Limpia; Aug. — Pappus a pair of 

 persistent diverging horns. 



344. T. (Abuceros, pappus nullus) longipes (sp. nov.) : suffruticosa, e basi ra- 

 mosissima ; ramis abbreviatis congestis conferte foliosis in pedunculum longissimum 

 simplicem nudum monocephalum desinentibus ; foliis 3 - 5-sectis, segmentis integer- 

 rimis vel 2-3-sectis lineari-filiformibus ; ligulis nullis ; acheniis subclavato-lineari- 

 bus incurvis rugosis calvis. — Hills and dry banks of the San Pedro or Devil's 

 Tliver ; July. Also abundant in the collection of 1851. — Stems six or eight inches 

 high, woody or lignescent, very numerous and crowded, and extremely leafy, each 

 terminated by a filiform naked peduncle of from six to ten inches in length. 

 Leaves glabrous ; the segments twelve to eighteen lines long, more slender than T. 

 gracilis. Involucre nearly as in the last-named species, but smaller, two or three 

 lines long, in fruit three or four lines broad, shorter than the flowers. Palese of the 

 receptacle one-nerved, carinate, deciduous with the achenia, but not adhering to 

 them as in the other species. Achenia slender, almost terete, tuberculate-rugose 

 when mature, especially on the back, the summit terminated with an obscurely 

 coroniform epigynous disk, but destitute of a pappus. In every other respect it is 

 truly a Thelesperma ; plainly showing that in this subtribe, as well as in the Hele- 

 nieee, in which numerous similar cases occur, the absence of a pappus is not of 

 generic importance, when there is a complete accordance in other characters. 



345. Bidens bipinnata, Lhuu; Torr. 8f Gray, Fl. 2. p. 354. Fields at Isletta, 

 New Mexico ; Oct.* 



346. B. tenuisecta. Gray, PI. Fendl. p. 86. Hill-sides near the Pass of the 

 Limpia ; Aug. 



347. B. CHRTSANTHEMOiDES, Mickv. ; Torr. ^ Gray, I. c. In the San Felipe 

 Creek, Western Texas ; Nov. 



348. Heterospermum dicranocarpum (sp. noA-.) : subglabrum ; caule erecto 

 apice corymboso-paniculato ; foliis 3 - 5-sectis, segmentis filiformibus ; pedicellis gra- 



* Bidens Beckii, Torr., belongs to the section PsihcarpcBa. The only mature fruit which I have seen 

 was communicated by Dr. Engelmann, from St. Louis. The teretish linear achenia are about half an 

 inch long, obtusely angled, smooth, bearing from four to six rigid and divergent awns, which are about an 

 inch long, pungent, retrorsely barbed only near the apex. 



VOL. III. ART. 5. — 15. 



