1288 CAKDUACEAE 



late, 3-10 cm. long, acute or acuminate, indistinctly 3-nerved, entire ; petioles 1-2 cm. 

 long : heads showy : involucral bracts linear or linear-spatulate, about 10 mm. long at 

 maturity, acute or acutish, glandular: ray-flowers 8-10, ligules rose-red, 1-1.5 cm. long, 

 5-cleft, or sometimes much reduced : achenes 6-8 mm. long, angled : pappus-scales various ; 

 those of the ray spatulate or oblong-spatulate ; those of tlie disk narrowly lanceolate, nearly 

 as long as the achene, attenuate into slender tips or awns. 

 On sandy plains, Nebraska to Texas. Summer and fall. 



5. Polypteris maxima Small. Annual, glandular-pubescent. Stems 3-8 dm. tall, 

 corymbose above : leaf-blades lanceolate to linear-lanceolate, 5-8 cm. long, acute or acumi- 

 nate, entire, ciliate, prominently 3-nerved, petioles 1-1.5 cm. long : involucral bracts 

 linear to linear-lanceolate, 1.5-2 cm. long at maturity : ray-flowers numerous ; ligules 8-12 

 mm. long, 3-cleft : achenes 6-7 mm. long, angled. 



On prairies, Texas. Summer. 



118. PALAFOXIA Lag. 

 Annual or perennial caulescent sometimes shrubby herbs, with pubescent foliage. 

 Leaves alternate or opposite : blades narrow, entire, the lower ones petioled. Heads dis- 

 coid, in corymbs. Involucres campanulate or oblong, several-flowered : bracts narrow, em- 

 bracing the approximate achenes : bracts narrow : receptacle flat, naked. Eay-flowers 

 wanting. Disk-flowers perfect, fruit-producing : corollas colored : lobes longer than the 

 cylindric throat. Anthers entire or emarginate at the base. Stigmas slender, obtuse 

 puberulent. Achenes 4-angled. Pappus of 4-8 unequal strongly ribbed scales. 



1. Falafozia Feayi A. Gray. Shrubby, minutely pubescent. Stems 6-15 dm. tall, 



widely branching : leaf-blades oblong to oblong-lanceolate, 2-7 cm. long, obtuse or acutish, 

 entire, commonly rounded at the base ; petioles 1-5 mm. long : involucral bracts linear or 

 linear-spatulate, 5-8 mm. long, obtuse : corollas 7-8 mm. long ; lobes at least ^ as long as 

 the throat : achenes 5-6 mm. long. 



In sandy soil, peninsular Florida. Summer and fall. 



119. BAHIA Lag. 



Shrubby plants or more or less woody perennial herbs, with white or pale, woolly or 

 more rarely glandular-pubescent foliage. Leaves opposite or alternate : blades dissected 

 or lobed, or the upper ones sometimes nearly or quite entire. Heads heterogamous, radi- 

 ate. Involucre ovoid to hemispheric : bracts in about two series, relatively broad, not em- 

 bracing the approximate achenes. Receptacles flat, naked or nearly so. Ray-flowers pistil- 

 late, fruit-producing, with yellow ligules. Disk-flowers perfect, fruit-producing. Anthers 

 obtuse at the base or merely emarginate. Stigmas of the perfect flowers linear, dilated at 

 the apex or with slender appendages. Achenes narrow, 4-angled. Pappus of 4-10 obovate, 

 oblong, or lanceolate, scarious scales. 



1. Bahia absiuthifolia Benth. Stem mainly herbaceous, 2-4 dm. tall, diffusely 

 branched, canescent-tomentose : leaves pale, opposite, or the upper alternate: blades pe- 

 dately or sometimes palmately 3-5-parted into lanceolate or linear segments : heads long- 

 peduncled : bracts of the involucre 5-7 mm. long, variable in shape, acute or slightly acu- 

 minate, lax : ligules of the ray-flowers yellow, 8-11 mm. long : achenes 4-5 mm. long. 



In dry soil, southern Texas to Arizona. Summer and fall. 



120. TETRANEURIS Greene. 

 Annual or perennial caulescent or mainly scapose herbs. Leaves alternate, sometimes 

 crowded on the branches of a woody caudex : blades entire, narrow. Heads heterogamous, 

 typically radiate. Involucres of 2-3 series of separate bracts. Receptacle convex or 

 conic, naked. Ray-flowers pistillate, fruit-producing, with yellow ligules. Disk-flowers per- 

 fect, fruit-producing. Anthers entire or minutely sagittate at the base. Stigmas truncate 

 and brush-like at the apex. Achenes broadened upward, 5-10-ribbed or angled, pubescent. 

 Pappus of 5-12 truncate or aristate scarious scales. 



Plants annual or perhaps biennal, caulescent. 1. T. linearifolia. 



Plants scapose : scapes tufted from branching perennial caudices. 2. T. linearis. 



1. Tetraneuris linearifolia (Hook.) Greene. Annual or perhaps biennial, some- 

 what villous-hirsute or glabrate. Stems simple and erect or diffusely branclied, the 



