152 TREES AND SHRUBS 



10. GYMNOLOMIA II. B. K. 



Annual or perennial eaulesc-nt herb- or shrubby pant-, with 

 pubescent foliage; leaves alternate or opposite; blades narrow, en- 

 tire or toothed; heads radiate, rather conspicuous; involucres henii- 

 spheric or campanulate; bract- narrow, in '-' ' series, the inner 



ones somewhat longer than the outer; receptacle more or less conic, 

 \ -. ray-flowers pistallate not fruit-producing; ligules yellow; 

 disk-flowers perfect, fruit-producing, with yellow or brownish cor- 

 ollas; stigmas of disk-flowers obtuse or with acute appendages; 

 achenes of the ray inane; those of the disk 4-angled, either some- 

 what fattened or turgid: truncate; pappus a denticulate crown, or 

 wanting. 



II. CRASSINA Scepin. Zinnia 



Annual or perennial ca r shrubby plants; 



-opposite; blades commonly narrow, entire or sparingly toothed; 

 heads radiate, often showy; involucres campanulate or somewhat 

 cylindric; bracts in 3 to 4 scries, firm, appressed. rather dry; recep- 

 i' cylindric, chaffy: ray-flowei >duc- 



ing; ligules red, purple or yellow, or variegated; disk-flowers per- 

 fruit-producing, enveloped in bractli disk- 



flowers truncate or subulate; achenes various; those of the ray 

 ise of the disk flattened: pappus of one or several awns 

 eth, or wanting. 

 A single woody species. 1.0. pvmila, 



12. CLAPPIA A. G 

 Perennial shrubby, but fleshy plants; alternate; bl 



ontirc or pinnatcly 3 to 5-parted; heads radiate: peduncled; in- 

 volucres hemispheric; bracts leathery, imbricated in 2 to 3 series, 

 broai e convex, bristly-fimbrillate ; ray-flowers 12 



to 15, pistillate, fruit-producing; ligules narrow, yellow; disk-flowers 

 perh i -producing : anthers entire at the base; stigmas of the 



disk with triangular appendages; achenes narrow, terete. 8 to 10- 

 nerved. hairy on the nerves: pappus of 20 to 25 scale-like hispidulous 

 bristles longer than the achene. 



A single species in "gyp" soils only: in the 

 Lower Sonoran Zone. 1- C. svacdae folia. 



