COMPOSITE 413 



34. LIATRIS. Blazing Star. Button Snakeroot. 



Perennial herbs, with simple erect stems from tuberous or corm-like 

 roots: leaves entire, alternate, rather rigid, sometimes vertical on the stem, 

 tmd resinous-dotted: flowers few to many, in raceraed or spicate heads: 

 flowers all alike, rose-purple, tubular: corolla 5-lobed, lobes long and 

 .slender: pappus of nianj' hair-like bristles, plumose or barbed: akene 

 slender, tapering to base: involucral bracts in several rows, unequal. 



L. scaridsa, Willd. Stem stout, 2-5 ft. tall: leaves lanceolate, the lower 

 long-petioled, the upper more linear and rigid: heads few to man\-, 30-40 

 flowered, about 1 in. broad: scales of involucre numerous, with rounded 

 tips, often colored and rather rough on the margins: flowers bright purple. 

 Dry soil. 



L. pycnostHchya, Michx. Heads 3-15-fio\vered: flowers rosy-purple on a 

 spike 3-4 ft. high: flowers begin to open at top of the spike and continue 

 opening downward: scales with purplish tips. A western species, cultivated; 

 very showy. 



35. EUPATORIUM. Boneset. 



Erect perennials, with simple leaves: heads small and rayless, clustered, 

 all the florets perfect: scales not leafy; torus flat or low-conical, naked: 

 ukene 5-angled: pappus a single row of soft bristles. Low grounds. 



E. purpiireum, Linn. Joe Pye weed. Tall, with purplish stem and lan- 

 ceolate-toothed leaves in whorls of 3-G: heads flesh -colored, in dense 

 corymbs, Swamps, growing 3-10 ft. 



E. perfoliatum, Linn. Boneset. Thorough wort. Fig. 159. Two to 4 ft., 

 hairy: leaves opposite and sessile, lanceolate: flowers white, in clusters. 



30. VERNONIA. Ironweed. 



Coarse perennial herbs, with tall strong leafy stems: leaves alternate 

 (seldom opposite), sessile: flowers 15 to many in a head, heads eorymbed, 

 all tubular, perfect, purple (rarely white or pink): involucre shorter than 

 flowers, with several series of scales: receptacle not chaffy: pappus double, 

 the inner series bristle-like, the outer of short, small, scale-like bristles: 

 akenes cj'lindrical, several-ribbed. 



V. Novaborac6nsis, Willd. A coarse weed, 3 to G ft.: heads about K in. 

 long: bracts of involucre, some or all, with slender long or awned flexuous 

 points, brownish-purple: leaves many, rough, lanceolate or lance-obloTig, 

 2 to 9 in. long, serrulate, sessile, all along stem: flowers deep purple in 

 spreading, flat-topped cymes: akenes somewhat hairy. Late summer. 



V. fasciculElta, Michx. Tall, coarse weed, 3 to 10 feet, with deep purple 

 flowers in heads (20 to 30 flowered), eorymbed: involucre campanulate, 

 scales usually obtuse, not awn-like. Summer and autumn. 



