392 DESCRIPTIONS OF NEW SPECIES 



bescent, the teeth linear and acuminate. Stigmas exserted, hirsute and fili- 

 form, subacute. Involucrum ovate, five-leaved, sepals lanceolate, embracing 

 the achenium. Receptacle naked, alveolate, excepting a verticillated, pent- 

 angular, five-toothed cup, interposed between the ray and disk. Achenium 

 of the ray obovate, three-sided, rugose and naked, with a minute rostrum ; 

 that of the disk turbinate, crowned with a pappus of four or five long, sca- 

 brous awns, and the same, or a smaller number of intermediate, minute, ob- 

 tuse, fimbriated scales. — An elegant and delicate annual, of a powerful, and 

 most agreeable odour; stem divaricately branching from near the base, 

 branches almost capillary; flowers solitary, terminal, fastigiate, white in 

 both ray and disk; involucrum viscidly glandular, subtended by three acerose 

 bractes. Leaves alternate, linear, hirsute, entire. Allied to Calycadenia, 

 but with the discal florets perfect, the palea of the receptacle united, and the 

 pappus double. — (The name from oa^ri, odour, and ah-^v, a gland; in allusion 

 to the fragrance of its glandular exudation.) 



Osmadenia *teneUa. 



Hab. St. Diego, Upper California. Flowering in May. Root simple, tap-shaped, slender. 

 Radical and lower stem leaves crowded, somewhat hirsute and strongly ciliate, two or three inches 

 long, less than half a line wide, and revolute on the margin. Branches very divaricate ; upper 

 stem leaves rather distant and acute, rigid, almost acerose. Stem six inches to a foot high, nearly 

 smooth and brown, spreading out usually more than its height. Three or four leaf-like narrow 

 bractes usually beneath the involucrum. Sepals lanceolate, shorter than the internal leaf-like invo- 

 lucrum. Rays about the lengtli of the involucrum, flat, cleft into three lanceolate segments down 

 to the base, the tube very slender, about the length of the border, nearly smooth. Stigmas of the 

 ray very long, filiform, equal and smooth. Stamens yellow. Achenium of the ray without pappus, 

 black, smooth, and shining, rugose, obovate, short, and three-sided, with a minute, projecting 

 epigynous disk, and a prominent narrow cicatrice at the base. Discal florets six to eight, the 

 achenium cylindric, turbinate, thinly villous, crowned with a pappus of four or five acuminated, 

 thick, scabrous, rigid awns, twice its length, between which are interposed alternately, and in- 

 ternally as many, or a fewer number, of obtuse fimbriated scales, less than a fourth their length; 

 the florets longer than the pappus, narrow tubular, with remarkably long, linear, acuminated, 

 glandular teeth; the stigmas exserted, long filiform, hirsute, rather acute. 



