366 DESCRIPTIONS OF NEW SPECIES 



HELIANTHUS. (Linn.) 

 Helianthus lenticularis. Decand. 



Hab. Banks of the Platte and the waters of the west, generally. 



~~ Helianthus *integrifolius; o, more or less hirsute with appressed hairs; 

 leaves nearly entire, below opposite, above alternate, ovate, or ovate-lanceolate, 

 three-nerved, petiolate, obtuse or acute; stem few-flowered; sepals lanceolate- 

 oblong, or ovate, acute, closely imbricated ; rays about twelve, rather short; 

 achenium villous. /3. gracilis; leaves denticulate, scarcely three-nerved; se- 

 pals acuminate. 



Hab. With the above, a small and rather dwarf species, sometimes slender, at other times robust, 

 leaves on long petioles. Stem sometimes almost simple (perhaps a different species;) in others 

 branching from the base, Capitulum pedunculate, about one and a half inches in diameter, or 

 smaller. Rays sometimes styliferous, with abortive fruit, bearing three awns; paleae of the recep- 

 tacle ovate, abruptly acute; young achenium almost silky ; disk brown. Allied to H. petiolaris, 

 particularly j3, gracilis, but with short peduncles and opposite leaves. 



Heliaiithus * silphioides; il, hirsute and scabrous; leaves petiolate, broad 

 ovate, subcordate, dilated, serrate, acute, below opposite, alternate above; up- 

 per part of the stem naked, paniculate, subcorymbose ; sepals oval, obtuse, 

 closely imbricate; squamse of the receptacle acute, somewhat three-toothed; 

 achenium smooth, pubescent at the summit; rays acuminated. 



Hab. In the plains of Arkansa, three or four feet high, and robust. Leaves nearly as wide as 

 long, about three inches. Capituli in a branching corymb, branches two and three-flowered. Rays 

 about twelve, acuminated, longer than the brown disk. Achenium spotted, subquadrangular, two 

 awned, Discal florets cylindric, rather narrower at base. — Allied to H. atrorubens, but a much 

 stouter and broader-leaved plant. 



Helianthus *pumilus; x, hirsutely pilose and scabrous; leaves ovate-lanceo- 

 late, opposite, attenuated below, subpetiolate, nearly entire, and three-nerved, 

 upper leaves lanceolate, alternate; involucrum hoary, hispid ; sepals imbricated, 

 lanceolate, acute, as well as the receptaeular palese ; achenia smooth. 



acute, scabrous and somewhat softly pilose; peduncle one-flowered, terminal; sepals in nearly a 

 simple series, oblong, acute. 



Hab. Maldonado, (Dr. Baldwin.) Stem slender and wiry, about a foot long, sending oft" a few one-fioweied 

 •branches towards the summit. Rays about ten to twelve, rather short. Achenium nearly smooth, with two awns, 

 ana numerous smooth squamellee. Receptaeular palese linear-lanceolate, acuminate. 



