AND GENERA OF PLANTS. 385 



ered; involucrum shorter than the globular, dark brown disk; rays few, flat, 

 three- toothed; pappus lanceolate, brown and awned, about one-third the length 

 of the discal floret. 



Hab. The plains of Red River, Arkansa. A very elegant species, with deep orange or dark 

 purple brown rays, pubescent externally. Stem three or four feet high, spreading and somewhat 

 naked at the summit, pedicels long and grooved, involucrum a little pubescent. 



Helenium *micranthum; nearly smooth ; radical leaves narrow, linear-lanceo- 

 late, entire; lower leaves oblong-lanceolate, sparingly denticulate, decurrent, 

 upper ones lanceolate, entire; stem slender, dichotomous; branchlets one to 

 two-flowered, peduncles moderate; involucrum hirsute, shorter than the sphe- 

 rical, brown disk; pappus about a third the length of the discal floret, hyaline, 

 apiculate; rays three-cleft, flat. 



Hab. South Carolina. Allied to H. nudiflorum, but the capitulum about half the size, and the 

 rays shorter, as well as the pappus, which is white, smaller and not awned. In H. quadridentatum 

 the radical leaves are bipinnatifid. 



Helenium Mexicanum. (H. B. and Kunth.) 



Hab. Louisiana. (Teinturier.) 



Division II. — Galinsoge^. (Decand.) 



*PTILONELLA. (Blepharipappus in part.) 



Capitulum few-flowered, radiate; rays about three, ligulate, feminine, dilated 

 and deeply three-lobed. Discal florets tubular-campanulate, five-toothed, 

 hermaphrodite, the centre ones sterile. Branches of the style short, obtuse, 

 rather smooth and exserted, the style hirsute; those of the rays smooth. Re- 

 ceptacle small, paleaceous, palea half-embracing, membranaceous. Involu- 

 crum subcampanulate, about eight-leaved, equal, the sepals half-sheathing, 

 oblong. Achenium turbinate, villous, crowned with a short circle of plu- 

 mose or ciliated pappus about a third its length; abortive central achenia 

 narrow-linear, with a pappus of fewer and less divided rays; (rays filiform, 

 from eighteen to twenty.) — An annual, much-branched, aromatic, slightly 

 hirsute and scabrous-leaved plant. Stem smooth. Leaves alternate, nar- 

 row, crowded, linear, entire. Flowers lateral and terminal, fastigiate, white, 

 vii.^4 w 



