NAT. ORDER. COMPOSITE. 171 



which exudes from the plant, as in the Sllphium gunimi/erum of Mr. 

 Elliott, and probably in other species of the genus, during- the hot 

 summers which are experienced in their native climates. But in the 

 northern and eastern States, no such exudation is observable, thoug-h 

 the sap yields a pecuhar odor. It is a stately plant, remarkable for 

 the great size of its lower leaves ; and though inhabiting- the western 

 mountains of Carolina and Georgia, and the prairies of St. Louis, on 

 the Missouri, it bears the open air of New England, and other noithern 

 States, remarkably ^vell — flowering in the autumnal montli. There 

 are three other species, natives of this country, -viz : 



SUphiuin laciniatum. Jag-ged-leaved Silphium. This has ' a 

 perennial root ; the stem rises from eight to fourteen feel in heiglit, 

 from one to two inches in thickness, quite simple, smooth below, above 

 rug-ged, with brown tubercles and white, spreading hairs, round ; the 

 leaves petioled, two feet in length and a fool in breadth, embracing at 

 the base, pinnatifid ; segments on each side four or five, distant narrow, 

 tooth sinuate, rugged, with very solid ribs raised on both sides ; mar- 

 gin of the upper leaves purplish ; the calyx of ten scales, ending iu 

 large awl-shaped spines ; the petals of tlie ray thirty, length of the 

 calyx, with a bifid, slender style ; the florets of the disk yellow, many, 

 separated by chaffs, attenuated at the base, with a simple style. It is 

 a native of North America, flowering from July till September. 



SUj)hium asteriscus. Hairy-stalked Silphium. This species has 

 a perennial root ; the stem four or five feet high, thick, solid, set with 

 prickly hairs, and having many purple spots ; the lower leaves alter- 

 nate — upper opposite and sessile, rough, about two inches long, and an 

 inch broad near the base, having a few slight indentures on their 

 edges ; the upper part of the stem divides into five or six small 

 branches, terminated by yellow radiated flowers like those of the 

 perennial Sun-flower, but smaller, having generally nine florets in the 

 ray. Native of North America, flowering from July to September. 



Silphium trifoUalmn. Three-leaved Silphium. This species has 

 a perennial and woody root ; the stems annual, rising about five feet 



