COMPOSIT.E. (cOMrOSITK FAMILY.) 199 



5. A. gracilis, Nutt. Stem slender, sliglitly pubesecnt, corvmbosc at the 

 summit ; leaves roiigli, oblong, partly elasping, entire ; the lowest obseurcly cre- 

 nato and narrowed into a petiole; heads corymbose; involucre (whitish) obeoni- 

 cal, as long as the disk ; the scales very unequal, acute, the lower ones much 

 shorter, green and slightly spreading at the tips. — North Carolina and Tennes- 

 see. Sept. — Stem l°-2<^ high. Leaves l'-2' long. Heads smallest of this 

 group. Kays about 12, violet. 



6. A. surculosus, Jlichx. Stems several from a creeping caudcx, slcn- 

 d-r, pubescent above ; leaves lanceolate or linear-lanceolate, acute, smootli, the 

 margins rough and sometimes sparingly serrate, clasping ; tlic lowest narrowed 

 into a petiole; heads solitary, or 3-.') in a simple corymb; involucre broadly 

 top-shaped, nearly as long as the disk ; the scales linear-spatulate, with abruptly 

 pointed spreading herbaceous tips ; the outer ones lanceolate and leaf-like. — 

 Margins of swamps. North Carolina. Sept. — Stems ^°-lA° high. Lowest 

 leaves 4'- C long. Heads ^' wide. Rays numerous, violet. 



7. A. paludoSUS, Ait. Stem slightly roughened ; leaves linear, rigid, 

 acute, entire, partly clasping, often fringed near the base; heads 3-8, racemed 

 or corymbed ; involucre hcmisjiherical, as long as the disk; the scales nearly 

 equal, linear-spatulate, with mucronatc green and spreading tips. — Low pine 

 barrens, Florida to North Carolina. Sept. and Oct. — Stem l°-2° high. 

 Leaves 2' -4' long. Heads ^-5' wide. Rays numerous, deep blue. 



8. A. spinulosus, n. sp. Rhizoma tuberous ; stem rigid, sprinkled with 

 white jointed hairs ; loaves rigid, narrow-linear, pungent, appressed, the mar- 

 gins fringed with bristly hairs ; the lowest ones very numerous and elongated ; 

 heads 4-8 in a simple spike; involucre bell-shaped, rather shorter than the 

 disk ; scales equal, lanceolate-subulate, rigid, erect, spine-pointed, bristly near 

 the base; achenia strongly ribbed. — Damp pine barrens, West Florida, near 

 the coast. June- August. — Stem 10' -L')' high. Lowest leaves C'-12' long, 

 l"-3" wide ; the upper ones 1' long. Heads J' wide. Rays 12-15, pale blue. 

 Pappus tawny. 



9. A. eryngiifolius, Torr. & Gray. Rhizoma tulierons ; stem rigid, 

 sprinkled with jointed iiairs; leaves lanceolate-linear, pungent, the lowest mostly 

 entire ; the others erect, and fringed with spiny teeth ; heads very large, solitary 

 or 3 - 4 in a loose raceme ; involucre hemispherical, shorter than the disk ; scales 

 very numerous, herbaceous, rigid, lanceolate, tapering into a long and slender 

 recurved tip ; achenia short, oblong. — Low ])ine barrens, Florida. June - Au- 

 gust. — Stem l°-2° high. Lowest leaves 4' -6' long. Heads 1' or more in 

 diameter. Rays numerous, white. 



^ .3. Aster proper. — Scales of the involucre imbricated in various degrees, with 

 herbaceous tips: raijs numerous: ctchcni a flattened: pappus of soft capillurij bris- 

 tles, not thickened upward: autumnal plants. 



* Leaves uniform, small, sessile, entire, silky or silvery on both sides, mucronate: 

 scales of the involucre imbricated in 3 -se vend rows: rays vioUl-purple. 



10. A. sericeus, Vent. Stem with numerous branches, bearing the large 

 heads (single or 3 in a cluster) at their summits ; leaves oblong-lanceolate, sil- 



