158 COMPOSITE. 



tusely dentate, 3-nerved, somewhat scabrous ; flowers in crowded corymbs. 

 Cttleslvna c&rulea Spreng. Eupatorium ccdestinum Linn. 



Woods. Penn. to Car. W. to Miss. Aug. Oct. 1|.. Stem 23 feet high. 

 Leaves on petioles, opposite, sometimes deltoid. Flowers in close fastigiate co- 

 rymbs, fragrant, light-blue. Involucre about 30-leaved, 40 60-flowered. 



Blue Conoclidium. 



7. EUPATORIUM. Linn. Hempweed. 



(Named after Eupator, king of Pontus.) 



Heads 3- many-flowered. Receptacle flat, naked. Involu- 

 cre cylindric or campanulate ; the scales in 1, 2 or many 

 series. Corolla tubular, funnel-form, often dilated at base. 

 Anthers included. Achenia angled. Pappus in a single series, 

 pilose, rough. 



* Heads, 5 15-flowered. Scales of the involucre oblong, imbricate. Leaves 

 opposite, closely sessile or connate. 



1 . E. sessilifolium Linn. : stem somewhat terete, smoothish ; leaves lan- 

 ceolate or ovate-lanceolate, sessile or somewhat clasping, rounded at base, 

 acuminate, serrate, smooth ; corymb compound ; heads 5-flowered ; scales 

 of the involucre 10, oblong-linear, obtuse, imbricate. 



Rocky hills. Mass, to Geor. Aug., Sept. %.> Stem 24 feet high, much 

 branched above. Leaves opposite but not connate, minutely dotted beneath. 

 Flowers in a widely spreading terminal corymb, white. 



Sessile-leaved Hempweed* 



2. E. truncatum Muhl. : stem terete, striate, villous-hispid ; leaves lan- 

 ceolate, clasping, obtuse at base, acuminate, rugose, dentate-serrate, villous- 

 pubescent beneath; corymb compound, crowded; heads 5 10-flowered; 

 scales of the involucre 12 15, imbricate, linear, obtuse. 



Shady woods. Penn. to Car. July Sept. 7j_. Very similar to the pre- 

 ceding, but has the stem pubescent, the leaves truncate at base, with the serra- 

 tures larger and more obtuse, and the involucre more pubescent. Willd. 



Truncate-leaved Hempweed. 



3. E. perfoliatum Linn. : stem villous-hirsute ; leaves connate-perfoliate, 

 lanceolate-oblong, acuminate, crenate-serrate, rugose, tomentose beneath ; 

 corymb compound ; heads 8 10-flowered. E. connatum Mich. 



Swampy grounds. Can. to Flor. W. to Miss. Aug., Sept. 1|~ Stem 2 4 

 feet high, hairy or woolly, branched at the top. Leaves large, sometimes only 

 slightly connate. Flowers in large fastigiate corymbs, white. The whole plant 

 is bitter and is used as a tonic. Big. med. Bot. i. 33. 



Bonesfi. Thoroughivort. 



4. E. resinosum Torr. ; stem erect, velvety pubescent ; leaves opposite, 

 closely sessile or partly clasping at base, linear-lanceolate, elongated, acu- 

 minate, serrate, nearly smooth above, velvety canescent beneath ; corymb 

 fastigiate, compound; heads glomerate, 10 15-flowered; scales of the in- 

 volucre oval, obtuse, imbricate, white-tomentose and glandular. 



Swamps. N. Y. and N. J. Penn. ? Aug., Sept. %.. Stems growing in 

 tufts, 2 3 feet high. Leaves membranaceous, viscid with resinous globules. 

 Heads rather small, very numerous. Resinous Hempweed. 



