COMPOSITE FAMILY. 191 



21. LIATRIS, BUTTON-SNAKEROOT or BLAZING-STAR. (An 



unexplained name.) Chiefly in pine-barrens or sandy soil. Fl. late summer 



and autumn. Il 



§ 1 . Stem commonly loand-like and simple, rising from a round corm or short tuber, 

 very leafy with narrow and entire often grass-like leaves : heads spiked or 

 racemed, or occasionally branching into a panicle, with imbricated involucre: 

 lobes of the rose-purple corolla lung and slender. 



* Bristles of the pappus plainly plumose to the naked eye. 



■y- Heads small, only 4 - b-flowered. 



Ii. tenuifdlia, in S. pine-barrens, has very slender mostly thread-shaped 

 leaves, stem 2° - 4° high, very slender raceme, and scales of involucre erect and 

 pointed. 



L. elegans, from Virginia S. ; 2° high, often hairy or downy, vv'ith com- 

 pact spike, short lanceolate or linear leaves, and scales of invqj^cre with spread- 

 ing rose-purple tips. 



■*- •*- Heads large and fewer, cylindrical, many-flowered. 



L. squarrbsa. Common Blazing-Star; from Penn. S. & W. ; l°-3° 

 high, with linear leaves, few heads about 1' long, and scales of involucre with 

 spreading leaf-like tips. 



L. cylindracea, from W. Canada S. W., smaller than the preceding, 

 6' - 18' high, the narrow heads with short and rounded appressed tips. 



* * Bristles of the pappus not plainly plumose to the naked eye. 



-r- Heads ^0 - 40-flowered, commonly an inch broad. 



L. soaridsa, with stout stem 2° - 5° high, lanceolate leaves, or the lower 

 spatulate-oblong, and very numerous scales of the involucre with rounded tips, 

 often scarious or purple on the margins. 



-t- H- Heads 3 - \5-flowered, from ^' to J' long: stem 2° - .5° high. 



L. pycnost^chya, in prairies W., with linear or lance-linear leaves, and 

 a very dense'spikc of about 5-flowered heads, the scales of the involucre with 

 recurving purplish tips. 



L. spic^ta, the commonest species ; in low grounds, with 8- 12-flowered 

 heads crowded in a long spike, the oblong and blunt scales of involucre without 

 any obvious tips. 



L. graminif61ia, in wet pine-barrens from New Jersey S., has 7 -12- 

 flowered heads in a looser spike or raceme, the rigid appressed scales blunt or 

 slightly pointed. 



L. gracilis, from N. Carolina S., with spreading leaves, the lower lancc- 

 oblong and long-petioled, the others linear and short, and 3 - 7-flowered small 

 heads on spreading pedicels. 



§ 2. No tuber or corm : leaves broad: heads small, in a corymb. 



L. Odoratissima, Vanilla-plant of low pine-barrens S. (also wrongly 

 called Hound's-tongue) : 2°-3° high, very smooth, with pale obovatc or ob- 

 long leaves which are vanilla-scented in withering, the heads 7 - 8-flowered, in- 

 volucre of few scales, and pappus not plumose. 



22. KtJHNIA. (Named by Linnaeus for Dr. Kidin of Pennsylvania.) 



K. eupatorioides, the only species from New Jersey to Wisconsin S., 

 is a rather homely herb, with lanceolate leaves, and panicled or corymbed small 

 heads of flowers, in autumn. Jl 



23. MIKANIA, CLIJIBING HEMPWEED. -(Named for a Bohemian 



botanist, Prof Mikan.) 



M. ScSindenS, a rather handsome plant, climbs over bushes in low grounds, 

 with triangular-heart-shaped or halberd-shaped leaves, and small heads of pur- 

 plish flowers, in summer. 2/ 



