350 COMPOSITE. Aster. 



lanceolate-acuminate ; rays numerous, rather short ; achenia slender, sparingly pubesceni, 

 5-8triate.— Nutt. gen. 2. p. 154 ; Ell. sk. 2. p. 343 ; Torr. ^ Gr. fl. N. Am. 2. p. 161. 

 A. sparsiflorus, Pursh,Jl. 2. p. 547; Torr. compend. p. 293 ; Beck, hot. p. 182. Tripolium 

 flexuosum, Nees, Ast. p. 155 ; DC. prodr. 5. p. 254. 



Stem a foot or eighteen inches high, a little angular, sometimes simple except at the sum- 

 mit, but usually producing a few and somewhat spreading short branches from towards the 

 base upward. Leaves 2-4 inches long and 1-2 lines wide, sessile, narrowed below, but 

 clasping at the base. Peduncles or branchlets bearing 1-2 heads, clothed with small bract- 

 like leaves. Scales of the involucre chartaceous, often tinged with purple. Rays about 20, 

 pale purple, about one-third longer than the involucre, in a single series. Pappus reddish. 



Salt marshes ; rather common in the vicinity of New- York and on Long Island. September 

 - October. 



26. Aster linifolius, Linn. Annual SaU-?narsh Aster. 



Annual ; very smooth ; stem erect, racemosely branched from the base ; the branches erect- 

 spreading, bearing racemose-paniculate (small) heads : leaves lanceolate-linear, acuminate, 

 narrowed at the base ; scales of the cylindraceous involucre linear-subulate ; ray-flowers 

 scarcely exceeding the pappus ; achenia minutely pubescent. — Linn. sp. 2. p. 874 ; Torr. <^ 

 Gr. Jl. N. Am. 2. p. 162, not oi Ait. <^c. A. subulatus, Michx.fi. 2. p. Ill (partly); Nutt. 

 gen. 2. p. 154 ; Ell. sk. 2. p. 345 ; Bigel. fl. Bost. p. 309 ; Torr. compend. p. 292 ; Beck, 

 hot. p. 181. Tripolium subulatum, Nees, Ast. p. 156 (in part); DC. prodr. b. p. 254 (partly). 



Stem usually about a foot and a half high, striate-angular, mostly purplish, generally much 

 branched, hollow. Leaves 2-6 inches long, somewhat fleshy, tapering at each end, 2-4 

 lines wide, somewhat clasping. Scales very acute, thin, green tinged with purple. Ray- 

 flowers numerous and very short, somewhat in two series, pale-purple or nearly while. 

 Achenia oblong. 



Salt marshes, in the neighborhood of New- York, and on Long Island ; common. September 

 - November. 



9. DIPLOPAPPUS. Cass. ; Torr. ^ Gr. fl. N. Am. 2. p. 180. diplopappus. 



DlIT.OSTEPHIDM, Kunlh. — DlPLOPAPPUS & DlPLOSTEPHIDM, CoSS. if- D.C. — DlPLOSTEFHICM & D<ELLINGERIA, in pait, 



Nccs. — Chrtsopsis, § 2. Nutt. partly. 

 [From the Greek, diphos, double, and pappos, pappus.] 

 Heads many-flowered ; the ray-flowers usually few (8 - 12), in a single series ; those of the 

 disk tubular, perfect. Scales of the involucre imbricated, lanceolate or subulate, destitute 

 of herbaceous or squarrose tips. Receptacle flat, somewhat alveolate ; the alveoh toothed. 

 Appendages of the style subulate or lanceolate, rarely short. Achenia more or less com- 

 pressed. Pappus double ; the interior of rough copious often unequal capillary bristles, as 



