Aster. COMPOSITE. 203 



syris? carnosa, Gray, PI. Wright, ii. 80. Bigelovia intricata, Gray, Proc. Am. Acad. xvii. 

 208, a slender form, with smaller heads. — Saline arid region, S. Arizona, Wright, to Cali- 

 fornia, in the Mohave Desert, Parry, Greene, Pringle, Parish, and near Visalia, Congdon. 



A. spinoSUS, Benth. Base of stem usually persistent and woody, sending up (3 to 8 feet 

 long) slender and lithe striate green branches, resolved into paniculate branchlets, terminated 

 by small heads : cauline leaves small, linear or spatulate-lanceolate, entire, mostly few and 

 fugacious, some of them with soft subulate spines in or above their axils; those of the 

 branchlets reduced to subulate scales or wanting : involucre hemispherical, 2 lines high, of 

 small and thinnish subulate-lanceolate bracts, imbricated in about 3 series : rays white, 2 

 lines long : style-appendages subulate-triangular, much shorter than the stigmatic portion : 

 akenes glabrous. — PI. Hartw. 20; Torr. & Gray, PI. ii. 165; Gray, PI. Lindh. ii. 219. — 

 Banks of streams, or in moist ground, S. W. Texas to Arizona and S. California, common ; 

 first coll. by Berlandier. (Mex.) 



A. Palmeri, Gray. Decidedly shrubby, with the habit of a small-leaved Baccharis, 3 or 4 

 feet high, very much branched throughout : branchlets slender, striate-angled, terminated by 

 the small heads : leaves apparently not fleshy, narrowly linear (of the branches an inch or 

 less long), entire : involucre equalling the disk, barely 3 lines high, of closely imbricated 

 narrowly oblong obtuse rather dry bracts : rays 6 to 10, a line long : disk-flowers about 20 : 

 akenes sericeous-pubescent. — Proc. Am. Acad. xvii. 209. Perhaps rather of the W. Indian 

 genus Gundlachia, Gray, Proc. Am. Acad. xvi. 100. — S. Texas, at Corpus Christi Bay, 

 Palmer. 



Series II. Biennials and annuals. 



§ 11. Oxtteipolium. Involucre of § Orthomeris ; the bracts thin and har- 

 row, linear-lanceolate or linear-subulate, gradually very acute or acuminate, 

 commonly greenish above or in the centre, but without herbaceous tips, imbri- 

 cated in few series, the outer successively shorter, all erect-appressed : rays at 

 least equalling the disk, numerous, often more numerous than the disk-flowers 

 (revolutely coiled in drying) : style-appendages lanceolate-subulate : akenes nar- 

 row, more or less pubescent, few-nerved : pappus fine and soft : glabrous and 

 smooth annuals, chiefly of saline soil, paniculately branched, bearing numerous 

 small heads, with bluish or purplish rays, and with entire narrowly lanceolate or 

 linear leaves, on the branchlets reduced to subulate bracts. — Gray, Proc. Am. 

 Acad. xvi. 98. Tripolium § Oxytripolia, DC. Prodr. v. 253, excl. spec. Tripo- 

 lium § Astropolium, Nutt. in Trans. Am. Phil. Soc. n. ser. vii. 296. Aster § Oxy- 

 tripolium, Torr. & Gray, Fl. ii. 161, in part. The two species are quite distinct 

 in the Atlantic U. S., but seemingly confluent in Mexico and S. America. 



A. exilis, Ell. Mostly slender and diffusely branched above : principal cauline leaves linear 

 • (3 or 4 inches long, 1 or 2 lines wide, lowest sometimes broader and lanceolate, rarely with 

 a few serratures) : heads 3 lines high : bracts of the involucre linear-subulate or more lan- 

 ceolate and acuminate : rays 15 to 40, bluish or purple, rather conspicuous (about 2 lines 

 long), usually much surpassing the pappus: disk-flowers generally more numerous. — Ell. 

 Sk. ii. 344; Torr. & Gray, El. ii. 163: believed to be the species here described; but the 

 original of herb. Ell. is now lost. A. divaricatus, Torr. & Gray, 1. c, not L., &c. A. subu- 

 latus, Michx. Fl. ii. Ill, in part. Tripolium subulatum, Nees, Ast. 157, in part; DC. Prodr. 

 1. c. 254, excl. var. boreale. Tripolium divaricatum, Nutt. Trans. Am. Phil. Soc. 1. c. 296. — 

 Subsaline or even not at all brackish moist soil, S. Carolina to Texas, Arizona, and Cali- 

 fornia; on the southern borders occurs with very short ligules. (Mex., W. Ind., &c.) 



Var. australis, the commoner Mexican and S. American form of this polymorphous 

 and widely diffused species, is less diffuse, less slender, often broader-leaved, and with larger 

 heads, the involucral bracts broader, less acute, and greener or purplish-tinged. — A. subu- 

 latus, Less, in Linn. vi. 120. Erigeron multiflorum, Hook. & Arn. Bot. Beech. 87. Tripolium 

 conspicuum of authors, but not the original of Lindley. — Coast of Oregon and California (at 

 "Visalia, in the interior, Congdon, a form with unusually large heads), &c. (Mex. to Chili, 

 Brazil, &c.) 



