416 DESCRIPTIONS OF NEW SPECIES 



two or three feet high, in the manner of the Furze bush of Europe, {Ulex.) Spines half an inch 

 to three-quarters of an inch long, sharp and somewhat curved. From under the flowering clusters 

 come out often tomentose branches, entirely clad with alternate spines, in two rows, in the axills 

 of which are formed buds, which afterwards produce leaves. Capituli on long peduncles; the 

 sepals distinctly carinate, oblong-lanceolate, receptacle entirely naked. The leaves thinly tomentose, 

 almost green. The villous hairs of the achenium shorter than in the preceding; bristles of the 

 pappus slender, and all similar. ' 



*LAGOTHAMNUS. 



Tetradymia, but with the capitulum five-flowered, the involucrum subcampa- 

 nulate, of five (or rarely six) flat, oblong sepals in a single series. Recepta- 

 cle naked, alveolate, dentate. Branches of the stigma subterete, obtuse, the 

 upper part, as well as the summit, pubescent. Achenium oblong, thickly- 

 clad from the base with long, slender, fastigiate, minutely serrulate hairs of 

 the same height with the true pappus, which consists of about twenty stout 

 and rigid barbellated bristles. — A decumbent, canescent, much branched, 

 spiny shrub. Leaves clustered in the axills of preceding slender spines, en- 

 tire, linear, minute, thick, almost acerose and smooth. Flowers solitary, 

 axillary, terminating small branchlets; the pedicels bracteolate, appearing, 

 from their situation above each other on the branch, to form a raceme; 

 branches and involucrum white and densely tomentose. — (The name alludes 

 to the soft, tomentose clothing of the plant.) 



Lagothamnus * microphyllus. 



Hab. On the arid plains of the Rocky Mountains, and near Lewis' River, as well as Ham's Fork 

 of the Colorado of the West: common. Flowering in July and August. A much branched, 

 spreading shrub, three or four feet high, with the young shoots, as well as their spines, soft and 

 whitely tomentose. Leaves clustered, oblong-linear, somewhat convex, perfectly smooth at all 

 times, scarcely more than two lines long, by half a line wide. Capituli mostly nodding, numerous ; 

 the florets bright yellow and large, deeply cleft, with smooth, linear, acute segments. Cone of 

 anthers exserted, the cusps linear and acute. Stigmas rather small, pubescent below as well as at 

 the summit. Involucrum conic-campanulate, three of the divisions oval obtuse, two other smaller 

 and acute. About twenty of the bristles which immediately surround the floret are about as stout 

 and as much barbellated as in Tetradymia. The most singular part of the plant is the pubescence 

 of the achenium, the hairs of which are very slender, and as much serrulated as in the true pappus 

 of Senecio, Avhich they wholly resemble ; they appear also nearly all of a length, and come up 

 nearly even with the few bristles of the true pappus. 



