AND GENERA OF PLANTS; 413 



Senecio * Schweinitzianus; n, smooth, stem grooved; lower and radical leaves 

 long petiolate, cordate, obtuse, or acutely cordate-ovate, coarsely or sharply 

 toothed, incise at base; cauline pinnatifid, auriculate and amplexicanle, the 

 auricle deeply cleft; umbell loose and subcompound; pedicels very long and 

 mostly naked; a few minute bractes under the base of the involucrum; in- 

 volucrum smooth, the sepals acuminate, about twenty; rays about twelve, 

 longer than the disk; achenium smooth; pappus nearly as long as the florets. 



Hab. In Arkansa, and, according to Schweinitz, in Carolina, marked S. CaroJiniana in his 

 herbarium, but not, apparently, the plant of Sprengel. About a foot and a half high, perfectly smooth, 

 except a slight down, in the axills of the radical leaves. Radical leaves with the petioles four or 

 five inches long, the lamina of the leaf two to three inches long, by one and a half to two broad; 

 umbell compound, with as many as twenty capituli. 



Senecio ^Plattensis; il, somewhat pubescent; base of the stem arachnoidly 

 tomentose; leaves all pinnatifid, the radical petiolate, cauline amplexicaule, 

 lobes oblong, denticulate, the centre lobe sublanceolate ; corymb nearly simple; 

 involucrum subcampanulate, minutely bracteolate; sepals about twenty, acute; 

 rays usually twelve, oblong, a little longer than the short involucrum ; ache- 

 nium puberulous; pappus about the length of the florets. 



Hab. In the Rocky Mountain range, and in Arkansa. About ten to fourteen inches high; stem 

 simple, striated. Corymb nearly simple, with ten to twelve heads of flowers, pedicels one to two 

 inches long, slightly bracteolate. The Arkansa specimen is taller and more slender, with the 

 primary small radical leaves entire and smooth, the leaves more elongated, and less denticulate. 

 The whole habit of the plant, as well as the flowers, are very similar to "S". tomentosus, at least the 

 smoother variety, but the achenium is less pubescent. 



Senecio *coronopus; o, smooth, dichotomously branched from the base; 

 leaves all pinnatifid, auriculately amplexicaule; the rachis wide, with few acute 

 segments, segments of the upper leaves denticulate; branches few-flowered, 

 fastigiate, pedicels elongated, naked, the summit beneath the campanulate in- 

 volucrum minutely bracteolate; sepals about twenty, smooth and carinated, 

 with acute, reflected, sphacelous tips; rays about fifteen, oblong, longer than 

 the involucrum; achenium cylindric, ten-ribbed, the ribs strigose; pappus about 

 the length of the florets. 



Hab. In Upper California, near St, Barbara. Flowering in May. A very distinct species, 

 allied, though remotely, to S. Californicus. The capituli, though fastigiate, are not in a corymb, 

 but terminate the forked branchlets. Flowers bright yellow. Stem much branched, six to eight 

 • VII. — 5 D 



