224 coMPOSiT.'E. (coMrnsiTK family.) 



coutracted into n short auriculate-clnflping ])etiole; heads single, or somewhat 

 nxi muse lit the ends of tlie branelies ; sciik-s of the invohicre narrow-linear, 

 with reenrvi'd subulate tips; rays slender, ])ale jiurjdi-. — Kiver swamps, 

 Florida to Soutli (':iri>liii;i. — Stem 4^- lO-" lonj^. Leaves I'-a' long. 



3U. A. Novae-AngliaB, L- Stem liairy or liispid, corymbose above ; 

 leaves lanceolate, acute, puliescent, scarcely narrowed at tlic auriculate-clasp- 

 iujx l>ase ; heads corymbcd ; scales of the involucre linear-suliulate, loosely 

 imiiricated, viscid; rays violet-purple. — Upper districts, in low ground. — 

 Stem 2° -4° high, mostly purple. Leaves 2'- 3' long. Heads Y t>r more in 

 diameter, immerous and siiowy. 



§5. Oktiiomekis. — Scales of the involucre regularli/ imbricated, scarious on 

 the man/ins, without herbaceous tips: pappus simple, soft-hair ij. 



40. A. acuminatus, Miciix. Pubescent ; stem erect, corymbose above ; 

 leaves large, oblung-lauceolate, acuminate, coarsely serrate, tapering at the 

 base; heads corym bed, on slender naked peduncles; scales of the involucre 

 linear-lanceolate ; rays w-hite. — Mountains of North Carolina, and northward. 

 Sept. — Stem 1°- 1^° 'ligt. Leaves thin, 3' -5' long, strongly veined. 



41. A. ptarmacoides, Torr. & Gray. Smooth or scabrous; stems (6'- 

 15' higli) simple ; leave.s liacar-Iauceolate, 1 -3-nerved; heads small, in a flat 

 corymb; scales of the involucre imbricated in 3 or 4 rows, sliort ; rays white. 

 — Northern States. 



Var. Georgianus, Gray. Taller {U°-2° high), and more slender, eor- 

 ynibosely branched above ; lower leaves lanceolate, sparingly serrate ; corymb 

 larger £^nd more loosely flowered ; ray flowers sterile, the style short or abor- 

 tive. — Mountains of Georgia. Sept. 



§ 6. OxYTRiPOLicM. — Scales of the invohicre witlwut herbaceous tips, scarious 

 on the marrjins : pappus simple, so/t-huiry : stems smooth and slender : leaves 

 narroiv, entire. 



* Perennial : scales of the involucre imbricated in several rows: rays conspicuou>f. 



42. A. Chapmani, Torr. & Gray. Stem erect, straight, branched above ; 

 lower leaves long (3' -9'), linear, spreading, the upper scattered, subulate, 

 erect ; heads large, terminating the slender branches ; scales of the involucre 

 lanceolate, rigid ; rays showy, purple ; achenia smooth, many-ribbed. (A. ex- 

 ilis, Ell. ? ) — Pine-barren swamps, West Florida. Oct. — Stem 2° -3° high. 



43. A. tenuifolius, L. Stem mostly reclining, flexuous, sparingly 

 branched ; leaves fleshy, narrow-linear; heads few, scattered, terminal, small : 

 scales of the involucre narrow-linear, very acute, the lower ones smaller and 

 passing into bracts ; achenia slightly hairy, .5-ribbed. — Salt marshes, common. 

 Oct. — Stem l°-3° long. Rays white or pale purple. 



* * Annual : scales of the involucre in 2-3 rows: rai/s short. 



44. A. SUbulatUS, Michx. Stem paniculately much branched ; leaves 

 linear-lanceolate, tapering at each end ; those of the branches linear or fili- 

 form, sessile ; heads small, very numerous, in leafy racemes ; scales of the 

 cylindrical involucre linear-subulate, smooth ; rays in two rows, not longer 

 than the disk ; achenia somewhat hairy, 5-ribbed. — Wet places along the 



