NAT. ORDER. COMPOSITiE. 171 
which exudes from the plant, as in the Silphium gummiferum 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 peculiar odor. It is a stately plant, remarkable for 
the great size of its lower leaves ; and thoug-h inhabiting- the western 
mountains of Carolina and Georg-ia, and the prairies of St. Louis, on 
the Missouri, it bears the open air of New Eng-land, and other northern 
States, remarkably well — flowering- in the autumnal month. There 
are three other species, natives of this country, viz : 
Silphium laciniatum. Jag-g-ed-leaved Silphium. This has a 
perennial root ; the stem rises from eig-ht to fourteen feet in heig-ht, 
from one to two inches in thickness, quite simple, smooth below, above 
rug-g-ed, with brown tubercles and white, spreading- hairs, round ; the 
leaves petioled, two feet in leng-th and a foot in breadth, embracing- at 
the base, pinnatifid; seg-ments on each side four or five, distant narrow, 
tooth sinuate, rug-ged, with very solid ribs raised on both sides ; mar- 
g-in of the upper leaves purplish ; the calyx of ten scales, ending- in 
larg-e awl-shaped spines ; the petals of the 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. 
Silphium asteiiscus. 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 trifoliatum. Three-leaved Silphium. This species has 
a perennial and woody root ; the stems annual, rising about five feet 
