394 Astereae 



4. GUTIERREZIA Lag, 



Herbaceous or suffrutescent, freely branching, some- 

 what resiniferous, nearly glabrous plants, with alternate 

 linear entire leaves, and numerous small heads corym- 

 bosely arranged at' the ends of the branches. Involucral 

 bracts coriaceous, the outer successively shorter. Ray- 

 and disk-flowers yellow. Achenes angled or striate, 

 mostly silky. Pappus paleaceous. 



1. G. divergens Greene. Suffrutescent, 4-7 dm. high, gla- 

 brous or merely granular-scaberulous, the panicled branches 

 nearly destitute of foliage at flowering time; involucres 6 mm. 

 high, obovate-turbinate, their obovate obtuse bracts well-imbri- 

 cated and with blunt green tips; disk-flowers 5-7; rays about 5; 

 palee of the pappus 9-12, very unequal, narrow and acute. 



Common on the interior plains and foothills, especially common on the 

 fans at the base of the mountains. July-August. 



5. PENTACHAETA Nutt. 



Small slender nearly glabrous annuals, with alternate 

 linear entire leaves, and mostly small heads solitary or 

 somewhat clustered at the ends -of more or less naked 

 branches. Involucre hemispheric or campanulate, its 

 bracts in 2 series, scarious-margined, appressed, mucro- 

 nate. Ray-flowers white, yellow or wanting. Disk-flowers 

 yellow, very slender. Style-appendages filiform-subulate, 

 hispid. Achenes pubescent. Pappus of 3-5 slender 

 bristles. 



1. P. aurea Nutt. Diffusely branching, 1-3 dm. high, some- 

 what villous-pubescent ; heads about 10-15 mm. broad, many- 

 flowered ; flowers all yellow ; rays obtuse, 20 or more ; involucral 

 bracts broadly lanceolate, setaceously acuminate, with green 

 middle portion and scarious margins ; achenes somewhat villous- 

 pubescent ; pappus bristles 5-8. 



Arroyo Seco, Davidson. Frequent in the Santa Ana Mountains and com- 

 mon throughout the coast slope of San Diego County. 



