1848.] 19 



0. *dendroidea. Leaves all linear, radical, hirsute; scape divaricately di and 

 trichotomoiis ; peduncles capillary; invohicrum about 3-flowered ; awns twice 

 the length of the involiicrum. 



Hab. On the sar.d hills of the Rocky Mountains, near Lewis' River. 



0. *fuliosa. Leaves liuear-lancsolate, hirsute ; divisions of the trichotomous 

 stem subtended by verticils of leaves ; awns of the involucrum about its length. 



H\B. With the above, which it much resembles ; it is, however, a much 

 stouter plant. The leaves about 2 inches-long and 2 to 3 lines wide. 



§. *GoMPHOiHECi Dioicous, Annualj stem naked, verticillately branched 



and very divaricate. Involucrum small, about 5-toothed, 5-flowered ; without 

 awns. 



0. *i(la/idulusa. Leaves all radical, roundish and pilose ; branches verticillate, 

 branchlets very numerous and divaricate, the ultimate ones and pedicels capillary; 

 flowers exserted, pubescent. 



Ha'b. Rocky Mountains of Upper California 



*STENOGONUM.t 



Monoicous. Involucrum none. Flowers naked, in axillary clusters. Perianth 

 triangular, 6-cleft. Stamens 6 ? Styles minute, with capitate stigmas. Achenium 

 conic, triangular, the angles sharp and salient, with a margin. — A small, smooth, 

 rather succulent annual plant of the Rocky Mountains, dichotomously subdi- 

 vided and branched ; leaves entire, opposite or ternate ; flowers yellow, in axillary 

 and terminal clusters, subtended by small, similar, leafy bractes. In the want 

 of involucrum, approaching Nemacaulis, but the habit, flower and achenium are 

 very distinct. 



6*. sahuginosu7n. 



Hab. Bare saline hills of the Colorado of the West, in the Rocky Moun- 

 tains. Flowering in June and July. (Nuttall.) 



*HELIOMERIS.J 



Capitulum many-flowered, heterogamous ; rays ligulate, in a single series, 

 neuter; discal florets tubular, hermaphrodite. Involucrum irregularly imbricated 

 and leafy, in about two series, and rather spreading. Receptacle conic, the palea 

 embracing the florets, lanceolate and acute. Corolla, rays ligulate, (10 — 12,) 

 those of the disk tubular, the tube short, throat wide and cylindric, border 

 5-toothed. Stigmata with oblong tips. Achenia laterally compressed, some- 

 what tetragonous, smooth, and without any pappus. 



H. multijtorus. 



A perennial tall herb, exactly resembling an Helianthus, with narrow, entire, 

 somewhat scabrous leaves, the lower ones opposite ; flowers yellow, terminal, 

 numerous. 



Hab. In Upper California, (Mr. Gambel,) and in the Rocky Mountains 

 collected by Mr. Gordon. 



CHRYSOTIIAMNUS. 



C. *depressus. Suffruticose and dwarf, nearly smooth; leaves rigid, 

 lance-linear, very acute, 1-nerved; flowers in small corymbs; involucrum 



fin allusion to the sharp and slender angles of the achenium. 

 tin allusion to its close affinity to Helianthus. 



