236 COMPOSITE. (cOMrOSlTE FAMILY.) 



involuri-c oblonfr-lincar ; rays wc<lgc-Rhapcd, palmatcly 3-lobed ; ovary wingless, 



with liis]ii(l margins. — Kiver-baiiks, South Carolina and Georgia. September. 



— Stem 2° -3° high. 



•»--•-•»- liai/s purple or rose<olor, 



16. C. nudata, Nutt. Smooth ; stem slender, forking above ; leaves al- 

 ternate, distant, terete, and rush-like ; rays bright purple, 3-toothed ; aehenia with 

 lacerated wings, 2-awned. — Pine-barren ponds, Florida and Gcorgiii, near the 

 coast. April. — Stem 2° high. Lowest leaves 1° long. Rays 1' long. 



17. C. rosea, Nutt. Smooth; stem low, branching; leaves opposite, lin- 

 ear ; heads small ; rays slightly 3-toothed ; aehenia wingless, una^vned. — 

 Swamps, Georgia, i\^u««//, and northward. July and August. — Stem 8'- 12' 

 high. Rays rose-color. 



18. C. CEmleri, Ell. Leaves broad-lanceolate, sessile, acute at each end, 

 entire ; peduncles axillary and terminal, dichotomously corymbose. — Collected 

 near the junction of the Broad and Saluda Rivers by Mr. CEmler. Elliott. — 

 Stem 2° -3° high, angular, smooth. Leaves connate by a small membrane. 

 Heads small. Rays about 8, entire. Aehenia wedge-shaped, slightly 2-toothed 

 and margined. ( * ) 



5L COSMOS, Cav. 



Scales of the involucre more or less united. Aehenia terete or 4-angled, nar- 

 rowed or beaked at the apex, and crowned with 2-4 downwardly barbed or 

 hispid deciduous awns. Otherwise like Coreopsis. — Leaves opposite, pinnately 

 divided. Disk yellow. Rays jiurpiish. 



1. C. caudatUS, Kunth. Smooth ; leaves bipinnately divided, with the 

 divisions lanceolate and entire; aehenia (1' long) tapering into a very long rough 

 beak, 2-awned ; rays short, 3-cleft, rose-color. — Key West, Florida. 



52. BIDENS, L. Beggar-ticks. 



Chiefly like Coreopsis ; but the exterior involucre often long and leaf-like ; 



the aehenia compressed, or 3 -4-anglcd, (not narrowed at the apex,) and crowned 



with 2-4 persistent downwardly barbed or hispid awns. — Leaves serrate, or 



pinnately divided, opposite. Rays yellow or white, often wanting. Disk 



yellow. 



* Aehenia Jlaltenfd, narrowli/ iccdije-shaprd. 



1. B. frondosa, L. Stem tall, branched ; leaves thin, long-pctioled, pin- 

 nately 3 - 5-divided ; the divisions ovate or ovate-lanceolate, acumiiuite, shar|)ly 

 serrate ; heads discoid ; exterior scales of the involucre large, leafy ; aehenia 

 2-awned. — Low ground, Florida and northward. July - Sept. (J) — Stem 

 2° -5° high. Margins of the aciienia upwanlly ciliate. 



2. B. COnnata, Muhl. Stem low, lir:in<li((l ; leaves oblong-lanceolate, 

 acimiinate, coarsely serrate, tapering and connate at the base, the lowest often 

 3-partcd ; licnds discoid ; exterior involucre leafy ; aehenia 2-4-nwned, with 

 downwardly lii-[)id margins. — Western districts of Georgia and westward, in 

 damp sijil. July - Sept. ® — Stem l^ - 2° high. 



