PLANTS COLLECTED BY DR. GAMBEL. 171 



*HELIOMERIS.t 



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 five-toothed. Stigmata 

 with oblong tips. Achenia laterally compressed, somewhat tetragonous, smooth, and 

 without any pappus. 



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

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

 numerous. 



H. *MULTiFLORUs. A stoutish perennial, three or four feet high, much branched ; stems terete and striated ; 

 leaves narrow, lanceolate, entire, nearly sessile, above somewhat scabrous, opposite below, on the 

 branchlets alternate ; flowers terminal, numerous and showy, bright yellow, with ten to twelve 

 rays, sometimes with deeper discoloured blotches towards the base or lower half, entire and oblong ; 

 leaflets of the calyx, oblong-lanceolate, somewhat spreading, in nearly a simple series ; achenia 

 black and smooth. Scarcely distinguishable from Helianihus, except by a short conic receptacle, and 

 naked seeds. 



Hab. Mountains of Upper California, (Dr. Gambel,) and was also collected in the 

 Rocky Mountains by Mr. Gordon. 



CHRYSOTHAMNUS. 



C. *DEPRESsus. Suffruticose and dwarf, nearly smooth ; leaves rigid, lance-linear, very acute, one- 

 nerved; flowers in small corymbs ; involucrum closely imbricated, the scales in five rows, lanceolate, 

 acutely acuminated, smooth, the lowest very small, one-nerved and somewhat carinate ; pappus 

 fulvous. 



Nearly allied to C. pumilus, but with a different involucrum. Achenia smooth, 

 five ribbed. 

 Hab. In the Sierra of Upper California. 



Chrysothamnus, by Torrey and Gray, has been referred to the genus Linosijris, of 

 the old world, with which, as I conceive, they have little if any affinity, as must appear 

 on comparing the characters of the two genera. Taking L. vulgaris for the type of 

 the genus, we observe that the hemispherical involucrum is scarcely imbricated, leafy 

 externally, with about one row, or scarcely two of scales, which are nearly flat ; the 

 florets very numerous, are very deeply divided ; the stigmas are elongated ; the 

 summit or appendage short and ovate, much shorter than the lower or stigmatic 

 portion. Pappus very copious, and scabrous, in several series, scarcely longer than 



t In allusion to its close affinity to Helianthus. 

 44 



