STANDLEY TREES AND SHRUBS OF MEXICO 1599 



Jalisco and Tepic; type from Jalisco. 



Shrubby, sparsely branched; stem glabrous except for hairy lines on the upper 

 internodes; leaves opposite, Hnear-lanceolate, 8 to 12.5 cm.' long, 7 to 17 mm. 

 wide, acuminate, entire, ciUate toward base, triplinerved; heads solitary or 

 ternate, yellow, radiate, 3 to 4 cm. wide, long-peduncled; involucre about 4- 

 seriate, graduate, 1.5 cm. high, with ovate appressed phyllaries; achenes narrowly 

 oblanceolate, about 8 mm. long; pappus of about 20 rigid barbate bristles, about 

 1 cm. long, slightly paleaceous-dilated at base. 



87. VENEQASIA DC. Prodr. 6: 43. 1837. 



Reference: Rydberg, N. Amer. Fl. 34: 5. 1914. 

 1. Venegasia carpesioides deltoidea (Rydb.) Blake. 



Venegasia deltoidea Rydb. N. Amer. Fl. 34: 5. 1914. 



Known only from the type locality, Sauzal, Baja Cahfornia. 



Suffrutescent, 50 cm. high and more, somewhat puberulous; leaves alternate; 

 petioles slender, about 2 cm. long; blades triangular-ovate, 5 to 8 cm. long, 2 to 

 3.8 cm. wide, acuminate, subtruncate to slightly cordate at base, dentate, thin; 

 heads radiate, yellow, about 4 cm. wide, terminal and axillary, nodding in fruit, 

 long-peduncled; involucre broad, about 3-seriate, about 1.2 cm. high, puberulous, 

 the outer phyllaries connate below, oval or oblong, herbaceous, with spreading 

 or reflexed tips, the inner membranous; receptacle hairy; achenes curved, about 

 3 mm. long, striate, glabrous, somewhat roughened, epappose. 



88. CLAPPIA A. Gray in Torr. U. S. & Mex. Bound. Bot. 93. 1859. 



Reference: Rydberg, N. Amer. Fl. 34: 5. 1914. 

 1. Clappia suaedaefolia A. Gray in Torr. U. S. & Mex. Bound. Bot. 93. 1859. 



Tamaulipas. Texas; type from Laredo. 



Suffruticose or herbaceous, much branched from base, low, pale green, glabrous, 

 very leafy; leaves alternate, linear or linear-filiform, 2 to 6 cm. long, 0.5 to 2.5 

 mm. wide, entire or trifid, fleshy, subterete or flattened; heads radiate, yellow, 

 about 3 cm. wide, solitary at tips of upwardly thickened peduncles about 5 

 cm. long; involucre about 4-seriate, graduate, about 7 mm. high, the phyllaries 

 oblong, rounded, glandular-vittate, thin-margined; receptacle densely paleaceous- 

 setose; achenes ribbed, sparsely hispidulous, 3 mm. long; pappus of about 35 

 unequal, hispidulous, setiform paleae, connate at extreme base, about 5 mm. 

 long. 



89. PSILOSTBOPHE DC. Prodr. 7: 261. 1838. 



Reference: Rydberg, N. Amer. Fl. 34: 6-9. 1914. 

 1. Psilostrophe cooperi (A. Gray) Greene, Pittonia 2: 176. 1891. 



Riddellia cooperi A. Gray, Proc. Amer. Acad. 7: 358. 1868. 



Northern Baja California. Nevada to California and Arizona; type from 

 Fort Mohave, Arizona. 



Shrub, forming clumps about 0.5 meter high; stem and branches densely 

 pannose-tomentose; leaves alternate, linear or linear-oblanceolate, 2 to 5 cm. 

 long, 1 to 4 mm. wide, entire, green in age; heads radiate, yellow, solitary or 

 cymose-panicled, 1 to 2.5 cm. wide; involucre narrow, equal, woolly, of erect 

 connivent phyUaries; rays about 5, broad, papery -persistent; achenes slender, 

 nearly glabrous; pappus of several usually oblong, obtuse or acute, hyaline 

 paleae. 



The other species of this genus are herbaceous or sometimes indurate at base, 

 but are never really frutescent. 

 57020—26 19 



