AND GENERA OF PLANTS. 365 



opposite, the rest alternate ; lower sepals foliaceous, sqnarrose, the inner linear-lanceolate. Rays 

 fifteen to twenty, twice as long as the disk, two-toothed at the tip, wholly abortive, pale yellow ; 

 discal florets cylindric, narrower below, with five erect, blunt, pubescent teeth. Stigmas some- 

 what ovate, with a short pubescence. Achenium obovate, compressed, ciliated, with two to four 

 subulate, rather wide awns from the angles, and about four minute, intermediate, obtuse squa- 

 mellae ; the awns scarcely as long as the achenium. 



Leighia *lanceolata; herbaceous, nearly smooth; stem terete, grooved, about 

 three or more flowered; intermediate leaves opposite, above and belovr alter- 

 nate, lanceolate, acuminate at each extremity, entire, petiolate, three-nerved; 

 involucrum foliaceous, subsessile; sepals linear-lanceolate, squamae retuse; 

 achenium short, obcordate, with two to three slender, persistent awns, twice 

 its length, the intermediate squamellse minute. 



Hab. Rocky Mountain plains and Upper California? Perennial; stem twelve to eighteen inches 

 high, smooth below; lower leaves six to eight inches long, an inch broad, a little pilose. Rays 

 about twelve to fourteen, pubescent beneath, twice as long as the disk, deep yellow. Paleae retuse, 

 pubescent at the tip. Achenium compressed, alated, smooth, (not ciliated,) short and obcordate, 

 with two or three very long, slender, scabrous, awns from the two compressed angles; squamellae 

 minute, acute, (in the germ appearing like mere hairs.) Mature seed not seen, in the young state 

 it somewhat resembles that of Actinomeris. 



Leighia? Hookeriana. Helianthus Hookerianus; Decand., Vol. V., p. 590. 

 H. longifolius; Hook. Flor. Bor. Am., Vol. I., p. 313, non. Pursh. Nearly 

 allied to the preceding, but with obtuse leaves, and broad, lanceolate, ciliate 

 sepals. The pappus apparently almost the same. 



Leighia longifolia. Helianthus longifolius; Pursh, non. Hooker. Interme- 

 diate squamellse of the achenium minute, mixed with a terminal tuft of hairs ; 

 the rest of the fruit smooth.f 



t To complete the history of this genus I will add the following species, collected in some parts 

 of South America, by the late indefatigable Doctor Baldwin. 



Leighia * Baldwiniana; herbaceous and scabrous, (apparently decumbent;) leaves crowded, 

 linear-oblong, entire, acute, sessile, three-nerved, the nerves running contiguous to the revolute 

 margin; panicle few-flowered, subcorymbose; sepals linear-lanceolate, acuminate, imbricate and 

 squarrose, somewhat triserial; achenium villous. 



Hab. South America; much like Helianthus angustif alius. Rays ten to twelve, twice as long as the disk. Stigma 

 pubescent, thick and obtuse. Pappus of two awns, and about six pilose, narrow, indistinct scales. 



Leighia ■'debilis; herbaceous and decumbent; stem terete, slender, and scabrous, as well as sparsely 

 pilose, above, to the base of the involucrum, hirsute; leaves sessile, opposite, linear-lanceolate, serrate, 

 VII. — 4 R 



