922 FLORA. 



its branches puberulent; bracts of the cylindric involucre all obtuse, the outer short, 

 puberulent. In moist soil, N. Y. and N. J. to eastern Tenn. and Wis. July-Sept. 



6. Eupatorium serotinum Michx. LATE-FLOWERING THOROUGHWORT. 

 (I. F. f. 3616.) Much-branched, finely and densely pubescent, or glabrate below, 

 12-25 dm. high. Leaves lanceolate or ovate -lanceolate, acuminate, sharply ser- 

 rate, 7-15 cm. long, 1-5 cm. wide, 5 -nerved at the base, the lower opposite, the 

 upper alternate; heads very numerous, the inflorescence broadly cymose; heads 

 7-15 -flowered, 4-6 mm. high; involucre campanulate, its bracts pubescent, linear- 

 oblong, obtuse or truncate; flowers white. In moist soil, Md. to Fla., Iowa, Kans. 

 and Tex. Sept.-Nov. 



7. Eupatorium leucolepis T. & G. WHITE-BRACTED THOROUGHWORT. 

 JUSTICE-WEED. (I. F. f. 3617.) Slender, puberulent, branched above, 3-6 dm. 

 high. Leaves linear, oblong or oblong-lanceolate, glaucous green, rough, thick, 

 blunt-pointed, sparingly serrate, or the upper entire, 3-7 cm. long, 4-10 mm. wide, 

 obscurely 3-nerved; inflorescence cymose-paniculate; heads 6-8 mm. high, about 

 5-flowered; bracts of the narrow involucre white, lanceolate, densely canescent, 

 the outer shorter; flowers white. In moist places, pine barrens of N. J. to Fla., 

 Ga. and La. Aug.-Sept. 



8. Eupatorium album L. WHITE THOROUGHWORT. (I. F. f. 3618.) 

 Pubescent with spreading hairs, branched above, 3-9 dm. high. Leaves obtuse, 

 obtusish or the upper acute at the apex, 3-10 cm. long, 1-2.5 cm - wide, rather 

 thick, minutely scabrous above, more or less pubescent beneath; inflorescence cy- 

 mose-paniculate; heads numerous, 8-iomm. long, 5-7-flovvered; involucre narrow, 

 its bracts bright white, linear, cuspidate, the outer short and usually pubescent, the 

 inner much longer, glabrous and shining; flowers white. In sandy soil, L. I. to 

 Fla., west to La. Aug.-Sept. 



Eupatorium klbum subvenbsum A. Gray. Leaves 2-5 cm. long, acute, less coarsely 

 serrate, prominently 3-nerved at the base; bracts of the involucre greenish. Eastern 

 L. I. and N. J. 



9. Eupatorium hyssopifolium L. HYSSOP-LEAVED THOROUGHWORT. JUS- 

 TICE-WEED. (I. F. f. 3619.) Roughish-puberulent, densely corymbosely branched 

 above, bushy, 3-6 dm. high. Leaves opposite, and fascicled in the axils, 1-5 cm. 

 long, 2-4 mm. wide, firm, narrowed at the base, margins usually revolute ; inflor- 

 escence densely cymose-paniculate; heads 6-8 mm. long, about 5-flowered; involu- 

 cre campanulate, its bracts linear or linear-oblong, sometimes apiculate, puberulent; 

 flowers white. In dry fields, Mass, to Fla. and Tex. Aug.-Sept. A plant from 

 the coast of Maryland with very narrow leaves, closely approaches Eupatorium 

 lecheaefolium Greene, from Florida. 



10. Eupatorium Torreyanum Short. TORREY'S THOROUGHWORT. (I. F. f. 

 3620.) Rootstock tuberous-thickened; stem usually densely puberulent, mostly 

 branched above, 4-9 dm. high. Leaves commonly with short leafy branches in 

 their axils, often drooping, acute, 2-7 cm. long, 4-12 mm. wide, usually distinctly 

 3-nerved, the upper and those of the branches much smaller, linear, entire; heads 

 about 6 rnm. high, generally 5-flowered; bracts of the campanulate involucre linear- 

 oblong, pubescent, or puberulent; flowers white. In dry soil, Penn. to N. Car., 

 Ky., Fla. and Tex. July-Sept. 



11. Eupatorium semiserratum DC. SMALL-FLOWERED THOROUGHWORT. 

 (I. F. f. 3621.) Pubescent or puberulent, loosely branched above, 6-9 dm. high, 

 leaves rather thin, short-petioled, narrowed at the base, 5-10 cm. long, 10-25 mm. 

 wide, 3-nerved, usually with short branches in their axils; heads 4-6 mm. high, 

 about 5-flowered; involucre campanulate, its bracts linear-oblong, canescent; flow- 

 ers white. In dry soil, Va. to Fla., Tex. and Ark. Aug.-Sept. 



12. Eupatorium altissimum L. TALL THOROUGHWORT. (I. F. f. 3622.) 

 Densely and finely pubescent, corymbosely much-branched above, 12-25 dm - high- 

 Leaves tapering below into a short petiole, roughish, rather thick, some of them 

 entire, strongly 3-ribbed, 5-12 cm. long, 10-25 mm. wide; heads about 5-flowered. 

 6-8 mm. high; involucre campanulate, its bracts oblong, densely pubescent; flow- 

 ers white. In dry open places, Penn. to N. Car., Ala., S. Dak., Neb. and Tex. 

 Sept. -Oct. 



13. Eupatorium sessilifolium L. UPLAND OR BASTARD BONESP.T. (I. F. f. 

 3623.) Glabrous throughout, or pubescent above, branched near the summit, 



