SiLPiiiuM. COMPOSlTiE. 275 



sterile. Involucre broadly campanulate ; the scales appressetl at the base, 

 more or less sprcadhig or loose and foliaceous at the summit, imbricated in 

 several series; the innermost (those next the achenia) very small and chaffy. 

 Receptacle small, flat, or somewhat turbinate when old ; the chaff linear, 

 flat, or slightly involute around the sterile ovaries. Corolla of the ray with 

 an elongated spreading ligule ; of the disk cylindrical; the teeth very short, 

 somewhat thickened and glandular, often pubescent or hairy externally. 

 Style in the sterile flowers undivided, much elongated, hispid. Achenia of 

 the ray broad and flat, obcompressed, imbricated in 3-4 series, surrounded 

 with a wing, which is notched at the summit, and usually confluent with 2 

 callous, subulate, or somewhat awn-like (often nearly obsolete) teeth, which 

 represent the pappus ; those of the disk abortive, slender, with an obsolete 

 coroniform pappus. — Stout perennial herbs (natives of the United States and 

 Texas), mostly hispid or scabrous, with a copious resinous juice. Leaves 

 alternate, opposite, or verticillate, entire, serrate, or lobed. Heads (large) 

 corymbose, jianicled, or solitary. Flowers yellow. 



* Stem terete, virgate or nearly tuilced : leaves large, alternate, or radical and on long 

 petioles, often sinuate, lobed, or pimuitchj pa.rted. 



1. S. laciniatum (Linn.) : hispid with white spreading hairs ; leaves pin- 

 nately parted, mostly petioled, but dilated and clasping at the base; the seg- 

 ments lanceolate or linear, sinuate-tootlied, incised, or pinnatifid, or some- 

 times entire, acute; heads (very large) few, racemose-sjjicate ; scales of the 

 involucre ovate, hispid and ciliate, produced into a long rigid and usually 

 squarrose acuminate appendage ; achenia orbicular-obovate, with a manifest 

 and scarious wing, deeply emarginate. — Linn.! spec. 2. p. 919; Linn. f. 

 dec. p. 5, t. 3; Ait.! Keiv. {ed. 1) 3. p. 267; Michx. ! Jl. 2. p. 145; 

 Pursh? fl. 2. p. 577; Jacq. f. eclog. 1. t. 90; DC! ptrodr. 5. p. 512; 

 Hook, compan. to hot. mag. 1. p. 99. (excl. syn. E. pinnatif.) S. spicatum, 

 Poir. diet. 5. p. 157. S. gummiferum, Ell. sk. 2. p. 460. 



(3. cauline leaves numerous towards the lower part of the stem, sessile 

 and clasping, ovate-lanceolate, laciniate-pinnatifid. 



Prairies from Iowa ! Wisconsin ! Missouri ! Illinois ! and Ohio ! to Ken- 

 tucky ! Alabama! Louisiana! Arkansas! and Texas! /3. Prairies of Ala- 

 bama, Mr. Buckley ! July-Sept. — Root thick. Plant exuding a copious 

 resin, 3-11 feet high. Stem simple, striate-grooved and nearly glabrous at 

 the base, somewhat naked above, clothed, as also the young heads, veins of 

 the leaves &c., with large very white jointed hairs arising from rigid papillas. 

 Lower leaves 12-30 inches long, often bipinnatifid, with an ovate circum- 

 scription, sometimes lanceolate and simply pinnatel}' parted, with the seg- 

 ments narrow and rather remote, eitlier entire or toothed. Heads frecpiently 

 2 inches in diameter, without including the rays, which usually exceed the 

 involucre : the lertninal one flowers earliest, and 2 or 4 others appear later 

 in the axils of often remote bracts, or of the upper leaves, either sessile or 

 peduncled. The var. /i., which came from the same region as Elliott's S. 

 gummiferum, does not however so well accord with his description as the 

 ordinary S. laciniatum, which varies greatly in foliage. In ibis variety the 

 incisions of the cauline leaves do not reach more than half-way to the mid- 

 rib. — Rosin-toecd. 



2. S. terehinthinaceum (Linn.): stem and peduncles glabrous; leaves 

 ovate and ovate-oblong, mostly cordate at the base, sharply serrate-toothed, 



