AND GENERA OF PLANTS. 376 



pubescent, with a thick, obtuse extremity, ending in a minute cone. Achenium short and striate, 

 covered loosely with long, soft hairs ; pappus scales white, lacerated, obtuse, about twenty, scarcely 

 exserted beyond the down. — Nearly allied to Chaenactis, but with the florets all regular. 



CH.ENACTIS. (Decand.) 



Capitulum many-flowered, homogamous; florets tubular, funnelform, the ex- 

 ternal series with the border dilated, ringent or palmate, five-cleft or five- 

 toothed, with the tube smooth and the dentures pubescent. Involucrum 

 campanulate, composed of two series of erect, linear sepals, (twenty to thirty,) 

 not membranaceous (or scarcely so) on the margin. Receptacle naked, al- 

 veolate, the margin sometimes paleaceous, the palese similar with the invo- 

 lucrum. Branches of the style hirsute, subulate, (without the conic apex.) 

 Achenia linear-tetragonal, attenuated almost into a pedicel at the base, pu- 

 bescent with appressed hairs. Pappus of four or five? lanceolate, acute, 

 membranaceous palese, in the ray shorter and obtuse. — Californian annuals, 

 with the habit of Hymenopappus. Leaves alternate, pinnately divided, with 

 narrow, entire, linear lobes; branches often naked at the summit, monoce- 

 phalous. Flowers yellow. Anthers naked at base. 



Chcenactis * tenuifolia; annual or biennial; at length smooth, much branched, 

 flowers fastigiate; leaves bipinnately dissected, segments narrow-linear, or 

 linear-oblong; rays funnel-formed, expanding longer than the disk; achenium 

 nearly smooth; pappus four-leaved; sepals pubescent, linear, acute; margin of 

 the receptacle paleaceous. 



Hab. St. Diego, Upper California. Flowering in May. About a foot high. Leaves very si- 

 milar to those oi Hymenopappus filifolius, alternate, the young shoots a little tomentose. Involu- 

 crum heniispherical, many-flowered, somewhat viscid; pedicels rather short. Style hirsute, subu- 

 late. Florets minutely pubescent; the flowers bright yellow. Stem about a foot high. Pappus 

 of the rays shorter and obtuse. — Nearly allied to C. glahriuscula, but the rays are not palmatifid. 

 In this species the margin of the receptacle is foliaceous, the radial florets being situated between 

 the outer and inner series of the sepals. 



Chcenactis Stevioides; (Hooker and Arnott.) 



Hab. In the Snake country. The rays palmatifid. Pappus four-leaved. Achenium four-an- 

 gled, nearly smooth. — A slender, few-flowered annual. Sepals oblong-lanceolate, nearly smooth, 

 about fifteen. Very nearly allied to the preceding. Flowers yellow ? 



