C0MP0S1TAE. 9 2 3 



6-18 dm. high. Leaves closely sessile, thin, sharply serrate, 7-15 cm. long, 

 1-3 mm. wide; heads S-io mm. high, about 5-flowered; involucre campanulate, 

 its bracts linear-oblong, the inner obtuse, the outer acutish; flowers white. In dry 

 woods, Mass. to Penn., 111. and Ala. xYug.-Oct. 



Eupatorium sessilifolium Brittonianum Porter. Leaves ovate or oblong-ovate, spar- 

 ingly and finely serrate, firm, rounded at the base, acute, the upper 2-5 cm. long, 

 12-18 mm. wide, pinnately veined, dark green; cymes dense, their branches puberulent. 

 Budd's Lake, X.J. 



14. Eupatorium verbenaefolium Michx. Rough or Vervain Thorough- 

 wort. (I. F. f. 3624.) Rough-pubescent, slender, 9-25 dm. high, branched at 

 the summit. Leaves obtuse or blunt-pointed, rounded at the base, more or less 

 crenate-dentate, 5-10 cm. long, 1-2.5 cm. wide, the upper pairs distant and small; 

 heads 5-flowered, about 6 mm. high; involucre campanulate, its bracts linear- 

 lanceolate, acute, densely pubescent; flowers white. In moist soil, Mass. to Penn., 

 south to Fla. and La. July-Sept. 



Eupatorium verbenaefolium Saundersii Porter. Leaves of the stem lanceolate or 

 lance-ovate, acuminate, not rounded at the base, strongly incised-dentate, with the teeth 

 mostly acute ; those of the inflorescence smaller and entire. Collected in a sphagnum- 

 bog near Willow Grove, Montgomery Co., Penn., by Mr. C. F. Saunders, for whom it is 

 named, and later in Tinicum, Delaware Co., by Mr. B. H. Smith. 



15. Eupatorium rotundifolium L. Round-leaved Thoroughwort. Wild 

 Hoarhound. (I. F. f. 3625.) Rough-pubescent, branched at the summit, 3-6 

 dm. high. Leaves broadly ovate, often as wide as long, acutish or obtuse, 

 truncate to subcordate at the base, coarsely dentate-crenate, 2 -5 cm. long, ascend- 

 ing; heads about 5-flowered, 4-6 cm. high; involucre campanulate, its bracts 

 linear-oblong, acute, densely pubescent; flowers white. In dry soil, southern N. Y. 

 to Fla., Ky. and Tex. Jrdy-Sept. 



16. Eupatorium pubescens Muhl. Hairy Thoroughwort. (I. F. f. 

 3626. ) Puberulent or pubescent, branched above, usually taller than the preceding 

 species. Leaves often twice as long as wide, rounded or truncate at the base, 

 coarsely dentate with acute or acutish teeth, or the lower incised-dentate; heads 

 5-8-flowered, 4-6 mm. high; involucre campanulate, its linear-oblong bracts in 2 

 or 3 series, the outer shorter; flowers white. In dry soil, N. H. and Mass. to 

 Penn., W. Va. and Fla, July-Sept. 



17. Eupatorium perfoliatum L. Common Thoroughwort. Boneset. 

 Indian Sage. (I. F. f. 3627.) Pubescent, stout, branched above, 6-15 dm. high. 

 Leaves opposite, or rarely in 3's, divaricate, lanceolate, long-acuminate with a 

 slender apex, finely crenate-serrate, rugose and pubescent beneath, 1-2 dm. long, 

 2-4 cm. wide; heads crowded, 10-16-flowered, 4-6 mm. high; involucre campan- 

 ulate, its bracts lanceolate, pubescent; flowers white, rarely blue. In wet places, 

 N. B. to Man., Fla., Neb. and Tex. July-Sept. 



Eupatorium perfoliatum truncatum (Muhl.) A. Gray. Leaves separated and truncate, 

 or somewhat rounded at the base. Occasional with the type. 



Eupatorium perfoliatum cuneatum (Engelm.) A. Gray. With leaves smaller, nar- 

 rowed and separated at the base, occurring in Ark. and Mo., is regarded by collectors as a 

 hybrid with E, serotinum. 



18. Eupatorium resindsum Torr. Resin Boneset. (I. F. f. 3628.) Slen- 

 der, resinous-pubescent, 6-9 dm. high, branched at the summit, the inflorescence 

 comparatively small, 7-10 cm. broad. Leaves closely sessile, clasping, or slightly 

 connate-perfoliate at the base, linear-lanceolate, long-acuminate, sharply serrate, 

 7-15 cm. long. 6-12 mm. wide, roughish above, canescent beneath; heads 10-15- 

 fljwcred; involucre campanulate, about 4 mm. high, its bracts oblong; flowers 

 white. In wet places, pine-barrens of X. J. Aug. -Sept. 



19 Eupatorium ageratoides L. f. White Snake-root. White Sanicle. 

 (I. F. f. 3629. ) Glabrous or nearly so, much branched, 3-12 dm. high. Leaves oppo- 

 site, thin, rounded, truncate or cordate at the base, or abruptly narrowed into the 

 slender petiole, coarsely dentate or crenate, 2-7 cm. wide, 3-nerved and veiny; 

 inflorescence rather loose, ample; heads 10-30-flowered; involucre narrowly cam- 

 panulate, about 4 mm. high; its bracts linear, acute or acuminate. In rich woods, 

 N. B. to Ga., Out.. S. Dak., Neb., the Ind. Terr, and La. July-Xov. 



