COMPOSITE FAMILY. 191 



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

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

 and autumn. ^ 



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

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

 r cenied, or occasionally branching into a panicle, with imbricated involucre: 

 lobes of the rose-purple corolla long and slender. 



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

 *- Heads small, only 4^ t> flowered. 



L. tenuifblia, 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. dlegans, from Virginia S. ; 2 high, often hairy or downy, with com- 

 pact spike, short lanceolate or linear leaves, and scales of involucre with spread- 

 ing rose-purple tips. 



*- *- Heads large and fewer, cylindrical, ninny flowered. 



L. squarrbsa, COMMON BLAZING-STAR; from Penn. S. & W. ; l-5 



high, witli 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. 

 *- Heads 30-<0-jluwered, commonly an inch broad. 



L. SCari6sa, with stout stem 2 - 5 high, lanceolate leaves, or the lower 

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

 often scarioua or purple on the margins. 



t- H- Heads 3- ]o-Jlowfred,from ' to \' long: stem 2- 5 high. 



L. pycnostachya, in prairies W., with linear or lance-linear leaves, and 

 a very dense spike ol ubotit 5-flowered heads, the scales of the involucre with 

 recurving purplish tips. 



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

 flowered beads 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 lance- 

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

 heads on spreading pedicels. 



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



L. odoratissima, VANILLA- PLANT of low pii.e-barrens S. (also wrongly 

 called HOUXD'S-TONGUK) : 2-b high, very smooth, with pale obovate 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 Linnseus for Dr. Kuhn 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. 11 



23. MIKANIA, CLIMBING HEMPWEED. (Named for a Bohemian 



botanist, Prof. Mikan.) 



M. scandens, 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. 3/ 



