CAKDUACEAE 1169 



ate-serrate, at least beyond the more or less cuneate connate-clasping bases : heads numer- 

 ous : involucres campanulate, 3.5-4 mm. high ; bracts mainly oblong, obtusish : corolla 

 white: achenes 1.5 mm. long. 



In low grounds, Missouri to Louisiana. Summer and fall. 



34. Eupatorium perfoliatum L. Tomentulose above. Stems 3-10 dm. tall : leaves 



opposite ; blades connate-perfoliate, lanceolate, 8-25 cm. long, acuminate, finely crenate- 



serrate : heads numerous : involucres narrowly campanulate, 6-7 mm. high, usually 10- 



flowered ; bracts linear-lanceolate, scarious and acuminate at the apex : corollas white, pink 



or rarely blue : achenes 1.5-2 mm. long. 



In low grounds. New Brunswick to North Dakota, Florida and Texas. Summer and fall. A state 

 with leaf-blades truncate at the base, is E. perfoliatum truncdtum A. Gray. Boneset. 



35. Eupatorium maculatum L. Foliage more or less pubescent, scabrous. Stems 

 0.5-2 m. tall, spotted with purple : leaves in whorls of 3-5 ; blades firm, ovate to ovate- 

 lanceolate, 0.5-2 dm. long, coarsely toothed : corymbs flat-topped : involucres 7-8.5 mm. 

 high, the outer bracts obtuse, pubescent : corollas pink or purple. 



In moist soil or swamps, New York to British Columbia, south to Georgia, Kansas and New Mex- 

 ico. Summer and fall. Joe-pye Weed. 



36. Eupatorium trifoliatum L. Foliage glabrous or sparingly pubescent. Stems 

 1-2 m. tall, often purple : leaves in whorls of 3-6 ; blades lanceolate to oblong-lanceo- 

 late, 1.5-2 dm. long, acute or acuminate, crenate : corymbs pyramidal : involucres 6-7 mm. 

 high, the outer bracts obtuse, puberulent : corollas similar to those of the next preceding 

 species. 



In moist soil, New York to Wisconsin, Georgia and Mississippi. Summer and fall. Joe-pye Weed. 



37. Eupatorium purpiireum L. Foliage glabrous or sparingly pubescent. Stems 

 1-3 m. tall, green or purple : leaves in whorls of 3-6 ; blades narrowly oblong, ovate- 

 lanceolate, oval or ovate, 1-3 dm. long, acuminate, serrate, sometimes pubescent on the 

 nerves beneath : corymbs more or less elongated, round -topped : involucres 5.5-6.5 mm. 

 high, the outer bracts acutish : corollas pink or purple, or rarely white. 



In moist soil or thickets, New Brunswick to Manitoba, Florida and Texas. Joe-pye Weed. 



11. CONOCLINUM DC. 



Perennial caulescent branching herbs. Leaves opposite : blades broadest below the 

 middle, often toothed or parted. Heads in corymbose clusters. Involucres campanulate 

 or hemispheric, several-flowered. Receptacle conic or hemispheric, naked. Corollas blue, 

 violet or rarely white, regular. Achenes narrow, 5-angled, truncate. Pappus of few hair- 

 like bristles in one series. Mist-flower. 



Leaf-blades palmately 3-5-cleft, or 3-5-parted. 1. C. Greggii. 



Leaf-blades entire or merely toothed. 



Larger leaf-blades about as broad as long. 2. C. dichotovucm. 



Larger leaf-blades about twice as long as broad. 



Stems or branches regularly leafy to the inflorescence. 3. C. coelcUinum. 



Stems or branches peduncle-like above. 



Leaf-blades manifestly toothed, cordate or subcordate at the base. 4. C. betonicum. 



Leaf-blades entire or essentially so, cuneate or truncate-cuneate at the base. 5. C. integrifolium. 



1. Conoclinum Greggii (A. Gray) Small. Finely pubescent. Stems 3-7 dm. tall, 

 each peduncle-like branch topped by a compact or rarely open cyme : leaf-blades 2-6 cm. 

 long, palmately 3-5-cleft or 3-5-parted, the lobes narrow, often again lobed : heads usually 

 crowded : involucres 4-5 mm. high ; bracts thin and pliable, very narrowly linear, acumi- 

 nate, finely pubescent : corollas blue-purple. [^Eupatorium Greggii A. Gray.] 



In low grounds, southern Texas to Arizona and adjacent Mexico. 



2. Conoclinum dichdtomum Chapm. Pubescent above with spreading hairs. Stems 

 erect or reclining, 3-9 dm. long, loosely forking : leaf-blades ovate, 1-4 cm. long, acutish, 

 shallowly crenate, broadly cordate at the base : heads few, not crowded : involucres 3-4 

 mm. high ; bracts rigid, linear-subulate, acute, pubescent : corollas blue. 



In sand, peninsular Florida. 



3. Conoclinum coelestinum (L.) DC. Pubescent with appressed hairs. Stems 2-9 

 dm. tall, branching especially above : leaf-blades ovate to deltoid-ovate, or rarely triangu- 

 lar-lanceolate, 3-12 cm. long, obtuse, crenate to serrate-crenate, abruptly narrowed or sub- 

 cordate at the base : involucres 3 mm. high ; bracts linear-subulate, acute, pubescent : 

 receptacle obtusely conic : corollas blue. [Eupatorium coelestinum L.] 



In shaded ground, New Jersey to Kansas, south to Florida and Texas. Summer and fall. 



4. Conoclinum betonicum DC. Pubescent with more or less spreading hairs. Stems 

 3-6 dm. long, ascending or spreading, the peduncle-like branches terminating in often con- 



74 



