GENUS 8. 



THISTLE FAMILY. 



365 



1. L. squarrosa. 



2. L. cylindrica. 



3. L, elegans. 



4. L. punctata. 



5. L. acidota. 



6. L. pycnostachya. 



7. L. sc arioso. 



tube slender, its limb 5-lobed or 5-cleft. Anthers obtuse at the base. Style-branches elon- 

 gated, obtuse or flattened at the apex. Achenes lo-ribbed, slender, tapering to the base. 

 Pappus of I or 2 series of slender barbellate or plumose bristles. [Latin, fringed, from the 

 appearance of the heads.] 



About 35 species, natives of eastern and central North America, known as Blazing Star, or 

 Button Snakeroot from the globular tubers. Type species : Serratula squarrosa L. 



* Bracts of the involucre acute, acuminate or mucronate. 

 Involucre cylindric, or turbinate, i5-6o-flowered, its base rounded. 

 Bracts with lanceolate spreading rigid tips. 

 Bracts mucronate, closely appressed. 



Involucre oblong, or narrowly campanulate, 3-6-flowered. 

 Inner bracts with prolonged petaloid tips. 

 Bracts all acute, mucronate or acuminate. 



Bracts appressed ; pappus-bristles very plumose. 

 Leaves \"2" wide; spike usually leafy below. 

 Leaves less than i" wide; spike mostly naked. 

 Tips of the bracts spreading ; pappus-bristles barbellate. 



** Bracts of the involucre rounded, obtuse or acutish. 

 Involucre hemispheric, Yz'-i' broad, is-45-flowered ; heads peduncled. 

 Involucre oblong, 2 "-4" broad, s-is-flowered. 

 Bracts obtuse, rounded. 



Involucre rounded at base ; bracts usually not punctate ; heads mostly sessile. 



8. L. spicata. 

 Involucre narrowed at base ; bracts usually punctate ; heads peduncled. 



Leaves, even the lower, narrowly linear ; involucre narrowly obovoid, s"-6" high. 



9. L. graminifolia. 

 Lower leaves linear-oblong; involucre broadly obovoid, 6" -7" high. 10. L.pilosa. 



Bracts acutish, punctate. n. L.Smallii. 



i. Lacinaria squarrosa (L.) Hill. Scaly 

 Blazing Star. Colic-root. Fig. 4177. 



Serratula squarrosa L. Sp. PI. 818. 1753. 

 Lacinaria squarrosa Hill, Hort. Kew. 70. 1769. 

 Liatris squarrosa Willd. Sp. PI. 3.: 1634. 1804. 

 Liatris intermedia Lindl. Bot. Reg. pi. 948. 1825. 

 Lacinaria squarrosa intermedia Porter, Mem. Torr. Club 



5: 314. 1894. 

 Liatris squarrosa var. intermedia DC. Prodr. 5: 129. 



1836. 



Usually stout, i-2 high, pubescent or glabrous. 

 Leaves narrowly linear, rigid, sparingly punctate, 

 3'-6' long, i"-2$" wide ; heads sessile or short-pedun- 

 cled, 1 5-60- flowered, usually few, or sometimes soli- 

 tary, i'-ii' long, 4"-8" thick; bracts of the involucre 

 imbricated in 5-7 series, lanceolate, rigid, acuminate, 

 glabrous or pubescent, their tips more or less spread- 

 ing when old; flowers purple; pappus very plumose. 



In dry soil, western Ontario to Pennsylvania, Virginia, 

 Florida, South Dakota, Nebraska and Texas. Called also 

 rattlesnake-master. Races differ in pubescence and in 

 size of the heads. June-Sept. 



2. Lacinaria cylindracea (Michx.) 



Kuntze. Cylindric Blazing Star. 



Fig. 4178. 



Liatris cylindracea Michx. Fl. Bor. Am. 2: 93. 



1803. 



Liatris graminifolia Willd. Sp. PI. 3: 1636. 1804. 

 Lacinaria cylindracea Kuntze, Rev. Gen. PI. 349. 



1891. 



Glabrous or nearly so, stout, i-ii high, 

 sometimes branched above. Leaves narrowly 

 linear, rigid, scarcely punctate, 3'-?' long, i"-2 ' 

 wide; heads several or numerous (rarely soli- 

 tary), peduncled, or the lower sessile, turbi- 

 nate-cylindric, i'-i' high, 4"-6" thick, 15-60- 

 flowered ; bracts of the involucre imbricated in 

 5 or 6 series, broadly oval, appressed, abruptly 

 acuminate at the apex; flowers purple; pappus 

 very plumose. 



In dry soil, western Ontario to Minnesota, south 

 to Illinois and Missouri. July-Sept. 



