100 
ageratoides, 
trifoliatum. 
purpureum. 
SYNGENESIA, ZQUALIS. 
Balm-leaved Hemp-weed. 
About one or two feet high. Flowers white. Leaves resem- 
ble those of common balm. In hedges and borders of sandy 
fields of Jersey, every where common. Perennial. August, Oc- 
tober. 
8. E. leaves petiolate, ovate-acuminate, three- 
nerved, unequal and deeply serrate, glabrous ; 
corymb many-flowered, divaricate ; calices sub- 
simple.--- Willd. 
E. ageratoides, L. and Willd. 
E.. urticefolium, Mich. 
Ageratum altissimum, Sp. Pl. ed. 2d. p. 1176. 
Icon. Morris. Hist. 3.s.7.t. 18. f. 11. 
Two or two anda half feet high. Flowers very white. Easi- 
ly known from other species. In thickets a little east of the 
Woodlands, and along the course of the Schuylkill; common. 
Perennial. August, October, 
9. EK. leaves petiolate, in three’s or four’s, ovate, 
attenuated at each end, serrate, somewhat sca- 
brous.—Wiulld. 
E. trifoliatum, Willd., not L. 
Three-leaved Hemp-weed. 
From four to five feet high, unbranched. Flowers reddish- 
purple. On the banks of our waters, in watery thickets and 
meadows, not uncommon. This and No. 10, resembles each 
other. Perennial. August, September. 
10. E. leaves petiolate, in four’s or five’s, ovate- 
lanceolate, serrate, rugose-veined, somewhat 
scabrous ; stem fistulous.—W tld, 
E. purpurea, L. ; 
Not. E. purpureum, Mich. 
Icon. Rob. ic. 217. Corn. Canad. t. 72. (Pursh.) 
Morris. Hist. 3.s.7.t. 13. f. 4. Dod. Mem. t. 
217. (Pursh.) 
Hollow-stemmed Hemp-weed. 
From five to six or seven feet high. Stem hollow, by which 
mark it can be always known. Flowers dark reddish-purple. 

