Genus 5.] 



THISTLE FAMILY. 



313 



19. Eupatorium coelestinum L,. 

 Mist-flower. (Fig. 3631.) 



Eupatorium coelestinum L- Sp. PI. 83S. 1753. 

 Conoclinium coelesti)inm DC. Prodr. 5: 135. 

 1836. 



Pubescent or puberulent, branched, i-3 

 high. Leaves opposite, petioled, ovate, ob- 

 tuse or acute at the apex, truncate at the 

 base, or abruptly contracted into the petiole, 

 crenate-dentate, lyi's' long, o/'-iS" wide; 

 inflorescence cymose- corymbose, rather com- 

 pact; heads 2 // ~3 // high; involucre broadly 

 campanulate, its bracts linear-lanceolate, 

 acuminate, equal or nearly so, in 1 or 2 

 series; receptacle conic; flowers blue or vio- 

 let. 



In moist soil, New Jersey to Florida, west to 

 Illinois, Kansas, Arkansas and Texas. Also in 

 Cuba. Aug.-Oet. 



5. WILLUGHBAEA Neck. Elem. i: 82. 1790. 



[Mikania Willd. Sp. PI. 3: 1742. 1804.] 



Herbaceous twining vines, or some tropical species erect shrubs, with opposite, petioled 



leaves, and discoid, mostly cymose-paniculate heads of whitish flowers. Heads 4-flowered. 



Involucre oblong, of 4 slightly unequal narrow bracts. Receptacle small, naked. Corolla 



regular, its tube slender, the limb campanulate, 5-cleft. Anthers entire and obtuse at the 



base. Style-branches elongated, acutish. * Achenes truncate, 5-angled. Pappus of numerous 



capillary roughish bristles in 1 or 2 series. [Probably named in honor of Francis Wil- 



loughby, 1635-1672, English naturalist, but the name spelled by Necker as above.]] 



About 150 species, natives of America. Besides the following another occurs in the southern 

 United States. 



i. Willughbaea scandens 

 (L,.) Kuntze. Climbing Hemp- 

 weed or Boneset. (Fig. 3632.) 



E. scandens 1,. Sp. PI. 836. 1753. 

 Mikania scandens W T illd. Sp. PI. 3: 1743. 



1804. 

 WillonghbyascandensTs.uniziz, Rev. Gen. 



PI. 371. 1891. 



Glabrous or nearly so, twining over 

 bushes, 5-i5 long. Leaves ovate or 

 hastate, deeply cordate at the base 

 with the lobes rounded or truncate, 

 acuminate at the apex, repand or ob- 

 tusely dentate, 2'-4' long, i / -2 / wide; 

 petioles slender, shorter than the 

 blades; heads in compound clusters 

 borne at the ends of the branches; invo- 

 lucre about 3" long, its bracts lanceo- 

 late, acuminate or apiculate; flowers 

 white or pink; achenes resinous. 



In swamps and moist soil, Massachu- 

 setts to western Ontario and Indiana, 

 Florida and Texas. Also in the West 

 Indies and South America. July-Sept. 



6. COLEOSANTHUS Cass. Diet. 10: 36. 1817. 



[Brickellia Ell. Bot. S. C. & Ga. 2: 290. 1S24.] 

 Herbs or shrubs, with opposite or alternate leaves, and discoid heads of white yellowish 

 or pink flowers, in panicles or cymes, or rarely solitary. Involucre campanulate or oblong, 

 its bracts striate, imbricated in several series, the exterior ones successively smaller. Re- 

 ceptacle flat or convex, naked. Corolla regular, 5-lobed. Anthers obtuse at the base. 



