PLANTS COLLECTED BY DR. GAMBEL. 177 



E. FOLiosuM. Rays narrow and very long. Achenium rather hirsute towards 

 the summit. Corymb with about seven to nine heads. A true species of 

 Erigeron. 



Hab. Monterey, California. 



CHiENACTIS. 



C. *r)ENUDATA. Biennial ; glandularly pubescent ; peduncles exceedingly long ; involucrum viscidly 

 pubescent, rather tomentose ; scales linear-lanceolate ; ray-flowers irregular, expanded, shorter than 

 the disk. 



Very nearly allied to C. lanosa, but with a distinct habit. Apparently a very 

 large species, with nearly naked peduncles more than a foot long, occasionally only 

 bearing one or two simple leaves. The leaves are pinnately parted, on slender 

 petioles, with three or four segments on a side. Flowers yellow, rather large, the 

 rays very evidently lobed. Achenia black, narrow fusiform, nearly glabrous, with a 

 pappus of about four lanceolate slightly lacerate scales. 



H AB. Pueblo de los Angeles, Upper California. 



DIETERIA. 



§. SiDEiiANTHUs. Involucrum hemispherical, the scales linear and acute ; achenia 

 obovoid and compressed, in the young state with numerous striatures, at length 

 covered with a silky villus ; pappus of several series of unequal scabrous bristles, the 

 outer series shorter and more slender, (those in the ray, as in the rest of the genus, 

 much shorter and less numerous.) Biennial or perennial, leaves pinnately lobed or 

 incised ; the lobes ciliated or pointed with bristles. Receptacle fimbrillate or chaffy. 

 Flowers of one colour. 



D. spiNDLOSA. NuTT. in Trans. Amer. Phil. Soc, 1. c. p. 301. Sideranthus 

 spinulosus. NuTTALL in Eraser's Catalogue, (1813.) Amellus? spinuhsus. Pursh. 

 Flor., V. ii. p. 564, (from the specimen which I gave to Mr. Lambert.) Torrey, 

 Ann. Lye. N.York, ii. p. 213. Slarkea? pinnata. Nutt. Gen. Am. ii. p. 169. 

 Diplopappus pinnatifidns. Hook. Flor. Bor. Amer. ii. p. 22. Aplopappiis spinulosus. 

 Decand. v. p. 347. Torrey & Gray, Flor. Am. ii. 240. 



D. rubiginosa. Aplopappus ruhiginosus. Torrey & Gray, Flor. Am. ii. p. 240. 



D. ^GRACILIS. Biennial, erect ; stem pilose, branched above, the one-flowered slender branchlets forming 

 a fastigiate corymb ; lower leaves pilose, pinnatifid ; the segments oblong, obtuse, upper leaves 

 linear, simple and sessile, entire, or minutely toothed, strongly ciliated with slender white bristles, 

 which terminate all the lobes of the leaves ; involucrum not viscid. 



