Aster. COMPOSITE. 161 



character may not be relied upon), and the scales are broader than in the 

 preceding. Mr. Douglas has labelled his specimens, " flower yellow", but 

 the rays appear to have been at most.only ochroleucous. If this be the case, 

 it is doubtless a distinct species ; if not, it may prove to be only a variety of 

 the preceding, as Hooker supposes. 



§ 6. Scales of the involucre imbricated in few-several series, membranaceous 

 or chartaceous with scarious margins, destitute of herbaceous tips, usually 

 very acute ; the exterior shorter and passing into scale-liJce bracts : recepta- 

 cle someiohat alveolate : rays numerous {rarely even in a double series) : ap- 

 pendages of the style subulate from a broad base, or triangular, acute : 

 bristles of the pappus soft and capillary, nearly equal : achenia compressed, 

 often striate : annual or perennial, mostly glabrous, and natives of salt 

 marshes: leaves thickish or succulent, narrow, usually entire. — Oxttripo- 

 tiUM, DC, under Tripolium. (Tripolium (' or perhaps sect, of Aster,') 

 § Astropolium, Nutt.) 



* Scales of the involucre regularly and closely imbricated in numero^is series : rays cx- 

 serted, in a single series (heads large) : perennial. 



119. A. Chapmanii : very glabrous ; stems simple or branched at the 

 base, long and slender, strict, somewhat corymbose at the summit ; the fili- 

 form branches terminated by single (large) heads ; leaves numerous, linear- 

 subulate, appressed, those of the branches reduced to subulate bracts ; scales 

 of the broadly obconical involucre closely and regularly imbricated in 5 or 6 

 series, slightly pubescent, ovate-oblong, acute or acuminate, the exterior 

 successively shorter ; rays elongated ; achenia oblong, compressed, very 

 glabrous. 



In swamps. Middle Florida, Dr. A. W. Chapman ! — Stems 2 feet or more 

 in height, virgate, not in the least flexuous, striate with lines produced from 

 the mtdrib of the leaves. Lower leaves 3-4 inches long ; the cauline about 

 a line wide at the appressed base, tapering to the subulate apex, successively 

 reduced upwards to half an inch or less in length, rather rigid, but not fleshy, 

 smooth on the njargins ; the uppermost sometimes cihate. Heads as large 

 as in A. flexuosus; the scales of the involucre broader (the exterior triangu- 

 lar-ovate), brownish, with a very narrow but distinct and abrupt scarious 

 margin. Rays 20 or more, large (three-fourths of an inch long), apparently 

 bluish-purple. Corolla of the disk sparsely pubescent below with minute 

 jointed hairs. Appendages of the style ovate-triangular, acute, flat, as long 

 as the oblong stigmatic jjortion. Pappus capillary, nearly in a single series, 

 as long as the corolla of the disk. Alveoli of the receptacle toothed. — A very 

 remarkable species. 



120. A. flexuosus (Nutt.): very smooth and glabrous; stem flexuous, 

 dichotomous ; the branches mostly terminated by (large) solitary heads ; 

 leaves linear-subulate, thick and fleshy ; the lower linear-lanceolate, acute, 

 tapering to the base ; those of the branchlets reduced to subulate-acuminate 

 scale-like bracts ; scales of the obovate involucre lanceolate or ovate-lanceo- 

 late, subulate-acuminate, unequal, imbricated in several series ; rays nume- 

 rous, rather short ; achenia slender, sparsely pubescent, strongly 5-striate. — 

 Nutt. ! gen. 2. p. 154 ; Ell. ! sk. 2. p. 343. A. sparsiflorus, Pursh ! fl. 2. 

 p. 547, iiot ofMichx. A. Tripolium ? Walt. Car. p. 154. Tripolium flora 

 unicocaulem terminante, &c. Clayt.! fl. Virg. cd. 1. p. 99. T- flexuosum, 

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



Salt marshes, Massachusetts ! and Connecticut ! to Georgia ! and Florida ! 



VOL. II.-21 



