CORTMPIFEREJE. 141 



dunclcf*. Bracts numerous^ spinous; spines arranged in pairs. Involucre 

 \einr\c\^c ; sralrs Inncoolato, simhtiv hairy. Seeds shining. Pappus plumoee. 

 Turple. '![. March — April. Voor soils, conuuon. 



Gexus XI. CENTAUREA. 



Involucre scaly ; scalers lanceolate, imbricate. lleccptacJe 

 bristlv. Florets o( the ray })i;stillate, tunnel-shaped, irregular, 

 those ot' the disk staniinate. Pappus consisting of three se- 

 ries, the exterior a toothed niarfjin, the middle one composed 

 of 10 or 12 aNvn.<. the interior one short, hairy. 



1. C. Bexedicta. Stem prostrate, soincwhat branched, woolly. Leaves 

 sessile, pinnatitid, with acute sci^inents, villous. Flowers sohtary, terminal. 

 Involucre ovate, with the scales terminated by a pectinate spine ; florets of 

 the ray S-cleft, those of the disk 5-cleft. Styles undivided. 

 Yellow. 0. June. Introduced. 



Sub-Ordkr hi. CORYiMBIFERE^. 



Inflorescence often corymbose, b'lt by no means always. 

 Capitula usually with disk and ray florets. Stigma not ar- 

 ticulated. 



(a.) Initlcc, Elicampane Tribe, 



Ge>ts XII. STOKESIA. 



Involucre leafy, imbricate. Corolla radiate ; florets of the 

 ray funnel forui, irregular, all perfect. Receptacle naked. 

 Pappus consisting of 4 bristles. 



1. S. Cyaxea. S/«n herbaceou?, leafy. LeawM lanceolate, i^oujer* soli- 

 tary, large, ornamental ; florets all perfect. 

 Blue or purple. %. May. Carolina. 



Genus XIII. LIATRIS. 



Involucre imbricate, oblong ; florets perfect. Pappus plu- 

 mose, persistent, generally colored. Fruit pubescent, striate, 

 ob-conic. Anthers entire at the base. Perennial, herbace- 

 ous plants, with alternate, entire leaves. Style bitid. Flowers 

 usually i)urple, all tubular. 



(a.) Flowers in spiJiCs or racemes. Root tuberous. 



1. L Spicata. S^c//i simple, glal)rous. Z<coivf linear-lanceolate, dabrous, 

 tcute. dottrd, somewhat ciliateat the base. Flowers in terminal spikes, with 

 bracteal leaves, /nro/ucre cylindrical; scales oblong- Generally 8 florets in 

 a capiiulum, longer than the involucre. Seeds hairy, furrowed. 



Gai/ feather. Button Snakernot, 

 Purple. % Aug.— Oct. Pine barrens, 'i-l feet. 



2. I^ Pvc.NosTAcnYA. Stem simple, hairv. Ij-avet narrow, linear, pubes- 

 cent. Ftowrrs in long, clustered spikes. Involucre squarrose at the summit, 

 apprcssed. 



Purple. %. September. Upper district of Carolina. 2-4 feet. 



