ORDER LXVIII. COMPOSITE. 375 



44. S. salici'na, (Ell.) Stein erect, slender, pubescent when young, 

 nearly glabrous when old, with long, erect, virgate branches. Leaven 

 sessile ; the lower ones long, narrow-lanceolate, scabrous on the upper 

 surface, glabrous on the under ; upper leaves smaller. Flowers in long, 

 slender racemes; involucre with oblong scales; ray florets s'ender, gen- 

 erally 5. — Yellow. If. Sept. — Oct. Middle Geo. 4 — 5 feet. 



S. patula, Muhl 



45. S. ela'ta, (Pursh.) Stem erect, terete, pubescent, with erect, to- 

 mentose branches. Leaves sessile, ovaManceolate, acute, tomentose be- 

 neath, nearly entire. Flowers in erect, paniculate racemes; involucre 

 wiih pubescent, linear-lanceolate scales; ray florets 7 — 10. Seed gla- 

 brous.— Yellow. If. Sept.— Oct. Middle Geo. 2—3 feet. 



S. petiolarh. 



46. S. rig'ida, (L.) Stem erect, slightly angled, tomentose when 

 young; branches numerous, fastigiate. Leaves ovate, sessile, pubescent, 

 scabrous; upper ones entire, the lower serrate. Flowers clustered near 

 the summit of the branches, large ; involucre with oblong, pubescent 

 scales; ray florets 7 — 10, those of the disk numerous. Seed glabrous. 

 — Yellow. If. Sept, — Oct. Mountains. 3 — 4 feet. 



47. S. craminifo'lia. (Ell.) Stem angled, slightly furrowed; blanch- 

 es numerous, expanding; angles pubescent. Leaves linear, numerous, 

 obscurely veined, pubescent along the veins on the under surface. 

 Flowers in fastigiate, terminal corymbs; involucre with numerous, vis- 

 cid, linear lanceolate scales; ray florets 10. short. Seeds villous. — Yel- 

 low. If. Sept. — Oct. Damp rich soils. 2 — 3 ft. S. lanceolata, L. 



48. S. tenuifo'lja, (Pursh.) Stem erect, angled, scabrous, with fas- 

 tigiate branches. Leaves linear, expanding, obscurely veined, scabrous, 

 clusters of small leaves in the axils. Flowers in fastigiate, terminal co- 

 rymbs ; involucre with viscid scales; ray florets about 10, very short. 

 Seed villous. — Yellow. If. Sept. — Oct. In dry pastures. Very 

 common. 3 — 4 feet. 



Genus XXII.— BIGELO'VIA. D. C. 

 (In honor of Dr. Bigelow, of Boston.) 



Heads few-flowered, the florets all perfect, tubular. Involu- 

 cre oblong, scales few, erect. Receptacle naked, narrow, with a 

 setaceous scale amoncr the central flowers, equaling the achenia. 

 Achenia oblong, pubescent. Pappus pilose, in one series. 

 Herbaceous plants, with alternate entire leaves. Heads in co- 

 rymbs, flowers yellow. 



1. B. nuda'ta, (D. C.) Stem erect, glabrous, branching near the 

 summit. Radical leaves spatulate, lanceolate, acute, 3 nerved, entire, 

 glabrous ; cauline leaves with the upper ones small and linear. Fioicers 

 in a compound fastigiate corymb; involucre with appressed linear 

 leaflets, colored, containing 3 — 4 flowers. Style about the length of the 

 stamens, 2-cleft; pappus unequal. — Yellow. If. Oci. — Nov. Com- 

 mon. 1 — 2 feet. Chrysocoma nudata, Mich. 



Genus XXIII— ISOPAP'PUS. T. & G. 



(From isos, equal, and pappus, from the equality of the pappus bristles.) 



Heads many-flowered; rays 5 — 12, ligulate, pistillate; disk 



