COMPOSITE. (COMPOSITE FAMILY.) 239 



4. M I K A N I A, Willd. CLIMBING HEMP-WEED. 



Heads discoid, 4-flowered. Involucre of 4 scales. Receptacle small. Flow\ 

 ers, acheiies, etc., as in Eupatorium. Twining perennials, climbing bushes, 

 with opposite commonly heart-shaped and petioled leaves, and corymbose-pan- 

 icled flesh-colored flowers. (Named for Prof. Mi/can, of Prague.) 



1. M. scandens, L. Nearly smooth, twining ; leaves somewhat triangu- 

 lar-heart-shaped or halberd-form, pointed, toothed at the base. Copses along 

 streams, E. New Eng. to Ky., and southward. July -Sept. 



5. EUPATORIUM, Tourn. THOROUGHWORT. 



Heads discoid, 3 - many-flowered ; flowers perfect. Involucre cylindrical or 

 bell-shaped, of more than 4 scales. Receptacle flat or conical, naked. Corolla 

 5-toothed. Achenes 5-angled ; pappus a single row of slender capillary barely 

 roughish bristles. Erect perennial herbs, often sprinkled with bitter resinous 

 dots, with generally corymbose heads of white, bluish, or purple blossoms, ap- 

 pearing near the close of summer. (Dedicated to Eupator Mithri dates, who is 

 said to have used a species of the genus in medicine.) 



1. EUPATORIUM proper. Receptacle flat. 



* Heads cylindrical, 5 - 1 ^-flowered ; the purplish scales numerous, closely im- 



bricated in several rows, of unequal length, slightly striate ; stout herbs, with 

 ample mostly whorled leaves, and flesh-colored flowers. 



1. E. purptireum, L. (JOE-PYE WEED. TRUMPET- WEED.) Stems tall 

 and stout, simple ; leaves 3-6 in a whorl, oblong-ovate or lanceolate, pointed, 

 very veiny, roughish, toothed ; corymbs very dense and compound. Varies 

 greatly in size (2-12 high), etc., and with spotted or unspotted, often dotted 

 stems, etc., including several nominal species. Low grounds ; common. 



Var. amcenum, Gray. Low ; leaves fewer, ovate or oblong ; heads few, 

 3 - 5-flowered. Mountains of Va. and N. Y. 



* # Heads 3 - 2Q-Jlowered ; involucre ofS - 1 5 more or less imbricated and unequal 



scales, the outer ones shorter; flowers white. 

 - Leaves all alternate, mostly dissected ; head spanieled, very small, 3-5-jlowered. 



2. E. fOBniculaceum, Willd. (DOG-FENNEL.) Smooth or nearly so, 

 paniculately much-branched (3-10 high); leaves 1 - 2-pinnately parted, fili- 

 form. Va., near the coast, and southward. Adv. near Philadelphia. 



*- H- Leaves long -petioled, the upper ones alternate; heads l2-l5-jlowered,in 

 compound corymbs. 



3. E. serotinum, Michx. Stem pulverulent-pubescent, bushy-branched 

 (3-7 high) ; leaves ovate-lanceolate, tapering to a point, triple-nerved and 

 veiny, coarsely serrate (3 - 6' long) ; involucre very pubescent. Alluvial 

 ground, Md. to Minn., E. Kan., and southward. 



*- - -- Leaves sessile or nearly so, with a narrow base, mostly opposite; heads 



mostly 5-flowered. 

 = Involucral scales with white and scarious- acute tips. 



4. E. album, L. Roughish-hairy (2 high) , leaves oblong-lanceolate, 



d, veiny ; heads cluster^ in th corymb ; inyolucral scales clo$g v 



