COMPOSITE. (COMPOSITE FAMILY.) 231 



with alternate leaves and solitary or corymbed heads. Flowers chiefly yellow. 



I Name from senex, an old man, alluding to the hoary hairs which cover many 



species, or to the white hairs of the pappus.) See Addend. 



* Rays none : root annual. 



1. S. TULGA.RIS, L. (COMMON GROUNDSEL.) Nearly smooth (6'-i2' 

 high) ; leaves pinnatifid and toothed, clasping ; heads loosely corymbed. 

 Waste grounds, E. New England and New York. (Adv. from Eu.) 



* * Rays present : root perennial : heads corymbed. 



2. S. aiiretis, L. (GOLDEN RAGWORT. SQUAW-WEED.) Smooth, at 

 floceose-woolly when young (10' -30' high) ; root-leaves simple and rounded, the lar- 

 ger mostly heart-shaped, crenate-toothed, long-petioled ; the lower stem-leaves lyre- 

 shaped, upper ones lanceolate, cut-pinnatifid, sessile or partly clasping ; corymb 

 umbel-like; rays 8-12. Varies greatly, the leading forms being, Var. 1. 

 OBOVATUS, with the root-leaves round-obovate (growing in drier places). 

 Var. 2. BALSAMITJS, with the root-leaves oblong, spatulate, or lanceolate, 

 sometimes cut-toothed, tapering into the petiole. Rocky places. Var. 3. LAN- 

 CEOL\TUS, Oakes, with the leaves all lanceolate-oblong, thin, sharply and un- 

 equally toothed, either wedge-shaped or somewhat heart-shaped at the base, the 

 upper merely pinnatifid-cut towards the base. (Cedar swamps, Vermont, Rob- 

 bins.) Common everywhere ; the primary form in swamps. May, June. 



3. S. Elliottii, Torr. & Gr. Soon smooth, stem simple (1 high), often 

 nearly leafless, bearing a small corymb ; root-leaves thickish, obovate or roundish, 

 narrowed into a short and winged petiole, or sessile, crenate-toothed, sometimes ly- 

 rate ; stem-leaves small, cut-pinnatifid. Rich soil, Virginia and southward 

 along the mountains. May. 



4. S. tomentosus, Michx. (WOOLLY RAGWORT.) Clothed with scarc&- 

 ly deciduous hoary wool (l-2 high) ; root-leaves oblong, obtuse, crenate-toothed, 

 on slender petioles; the upper sessile; corymb flat-topped; rays 12-15. 

 Mountains of Penn. (Pursh), Virginia and southward. May. 



5. CANUS, Hook., which too closely resembles the last, probably occurs 

 within our Northwestern borders. 



64. ARNICA, L. ARNICA. 



Heads many-flowered, radiate ; the rays pistillate. Scales of the bell-shaped 

 involucre lanceolate, equal, somewhat in 2 rows. Receptacle flat, fimbrillate. 

 Achenia spindle-shaped. Pappus a single TOAV of rather rigid and strongly 

 roughened^-denticulate bristles. Perennial herbs, chiefly of the mountains and 

 cold northern regions, with simple stems, bearing single or corymbed large 

 heads and opposite leaves. Flowers yellow. (Name thought to be a corruption 

 of Ptarmica.) 



L A. mollis, Hook. Soft-hairy; stem leafy (l-2 high), bearing 1 to 5 

 heads ; leaves thin, veiny, smoothish when old, toothed ; the upper ovate-lanceolate, 

 closely sessile ; the lower narrower, tapering into a margined petiole ; scales of 

 the involucre p>ointed ; pappus almost plumose. Alpine rivulets, &c., White 

 Mountains of N. Hampshire and mountains of N. New York : Lake Superior, 

 Prof. Whitney ; raid thence northwestward. July. 



