AND GENERA OF PLANTS. 409 



Senecio * rapif alius; smooth ; stem nearly erect, angular and striated, leafy ; 

 leaves spathulate-obovate, acute, the radical ones petiolate, cauline amplexi- 

 caule, the uppermost lanceolate or ovate, all sharply and unequally dentate, 

 the base sometimes runcinate; corymb paniculate; involucrum cylindric, small, 

 about fifteen-flowered; sepals linear-lanceolate, about eight to ten; pedicels 

 bracteolate to their summits; achenium smooth and angularly striated; pappus 

 shorter than the florets. 



Hab. Towards the Rocky Mountains, along the upper branches of the Platte. Allied in habit 

 and affinity to S. cacaliasler, which is also sometimes without rays. Obs. The root tuberous, 

 stout and perennial. Many stems from the same radical crown, somewhat decumbent, about a 

 foot high, every where quite smooth and shining. The leaves very much like those of Sonchus 

 oleraceus, sharply toothed, tlieir outline pretty much that of Brassica rapa, inclining to be 

 lobed or incise near the base, four or five inches long, by two or three wide; the lower leaves of 

 the stem with broadly alated petioles; upper part of the stem branching, the branches all corym- 

 biferous; umbellets with three to five or six capituli; the pedicels with several subulate bractes, 

 a few of which also approach the base of the involucrum; sepals membranous on the margin, a little 

 pubescent, but not sphaceolous at the tips. — (In my herbarium this species was first marked by the 

 name of S. * argnlus, which I have changed for the present, as more applicable.) 



1 1 Capituli radiate. 



Senecio *Andinus; smooth; stem erect, angular and grooved, very leafy; 

 leaves elongated, linear-lanceolate, acute, sharply serrulate, corymb compound, 

 paniculate; pedicels long, bracteolate, smooth; involucrum turbinate-cylindric, 

 of twelve to fifteen sepals, sphacelate at the tips; bractes beneath the involu- 

 crum rather numerous, subulate; flosculi about twenty; rays six to eight, about 

 the length of the involucrum; achenium smooth, pappus as long as the florets. 



Hab. In the valleys of the highest of the Rocky Mountains or Northern Andes, at an elevation 

 of about six thousand feet above the level of the sea. Flowering in July. Very nearly allied to 

 "S". sarracenicus, which extends to the Altaic Mountains. About a foot high, and full of leaves, 

 three to five inches long, by half to three quarters of an inch wide ; the corymb often very irregular, 

 made up of many slender, fastigiate flowering branchlets; the flowers small. 



Senecio integerrimus, (Nutt. Gen. Am. and Decand., Vol. V., p. 432.) 



Hab. On the plains of the Platte, towards the Rocky Mountains. My specimens diff'er some- 

 what from those of the Missouri, in not affecting wet places; the upper part of the stem in these 

 is occasionally sprinkled with a few soft hairs. The stem twelve to eighteen inches high, nearly 

 terete, and simple; the lower and radical leaves frequently oblong, or oblong-lanceolate, sometimes 

 denticulate, the stem leaves narrow-lanceolate, amplexicaule, acute, or acuminate, diminishing so 

 rapidly upwards as to give the stem much the appearance of a scape. Corymb small and con- 

 VII. — 5 C 



