1907] Hall. Compositae of Southern California. 57 



less distinct vertical ranks, chartaceous or coriaceous, mostly des- 

 titute of herbaceous tips. Ray-flowers uniformly lacking; disk- 

 flowers 5 to 30. Style-branches subulate or filiform, in all our 

 species long-exserted. Achenes narrow, terete or slightly 

 angled, pubescent. Pappus copious, soft, commonly dull white or 

 reddish. 



Chrysothamnus is connected by our first two species with 

 Ericameria ; by our last species with Haplopappus (Macronema). 

 From Bigelovia (Chondrophora, Chrysocomanudata) it differs in 

 habit and geographic distribution, that being a perennial herb of 

 the Atlantic seaboard, extending west to Texas. Bigelovia has, 

 moreover, shorter and thicker style-appendages, short somewhat 

 turbinate and nearly or quite glabrous achenes, and a rigidulous 

 pappus. 10 



Branches glabrous. 



Herbage resinous-punctate: leaves terete. 



Outer involucral bracts with a distinct greenish subapical spot 



1. C. teretifolius. 



Involucral bracts pale, wholly naked 2. C. paniculate. 



Herbage not resinous-punctate: leaves narrow but plane 'or canaliculate. 



Stems leafy: involucre 5 to 8 mm. high. 3. C. viscidiflorus. 



Stems nearly leafless: involucre about 1 cm. high: glabrate state of 

 4. C. Mohavensis. 



Branches clothed with a dense white tomentum. 



Leaves sparse: involucral bracts obtuse, the vertical ranks very distinct 



4. C. Mohavensis. 



Leaves numerous. 

 Heads 5-flowered. 



Involucral bracts abruptly contracted to a spreading setiform tip 



or short awn... 5. C. ceruminosus. 



Involucral bracts not abruptly tipper ...~6. C. nauseosus. 



Heads about 9-flowered: involucral bracts acuminate, a few of the 

 outer ones foliaceous 7. C. Parryi. 



1. C. teretifolius (Dur. & Hilg.) Hall, comb. nov. Linosyris 

 teretifolia Dur. & Hilg, Pacif. R. Kept. v. 9, pt. 3, t. 7. (1856). 

 Bigelovia teretifolia Gray, Proc. Am. Acad. viii. 644 (1873). 

 Chrysoma teretifolia Greene, Eryth. iii. 12 (1895). 



10 Cf. Greene, Eryth. iii. 91, 92 (1895). 



