THISTLE FAMILY 925 



pistillate flowers. Receptacle convex, with a series of linear-oblong or spatu- 

 late paleae, subtending the outer series of the central flowers. Marginal flowers 

 t>-8, pistillate and fertile, with an obliquely cleft corolla-tube. Central flowers 

 hermaphrodite but sterile, 40-50, with funnelform corollas. Anthers entire at 

 the base. Achenes oblong-obovate, glabrous, wingless, but acutely angled, 

 with an incurved apiculation. Pappus wanting. 



1. P. mollis A. Gray. Annual, with the odor of Arl'misia; stem 1-2 m. 

 high, paniculately branched; leaf-blades rhombic-ovate or the lower subcordate, 

 8-15 cm. long, acuminate, sinuately and often doubly dentate, cinereous-puberu- 

 lent; involucres hemispheric, 3 mm. high and 4-5 mm. broad; corollas greenish 

 white. Hillsides along streams: s Colo. — N.M. — Ariz. Son. Au-S. 



64. CRASSINA Scepin. 



Annual or perennial herbs or shrubby plants. Leaves opposite, commonly 

 narrow, entire or sparingly toothed. Heads radiate. Involucres carnpanulate 

 to nearly cylindric; bracts in 3-5 series, firm, appressed, rather dry. Receptacle 

 conic to nearly cylindric, chaffy. Ray-flowers pistillate, fertile; their ligules 

 red, purple, or yellow, or variegated, in ours yellow, persistent and becoming 

 papery. Disk-flowers hermaphrodite, fertile, enveloped in the paleae. Achenes 

 various, those of the rays 3-angled, those of the disk-flowers flattened. Pappus 

 of one to several teeth or awns, or lacking. [Zinnia L.] 



Ligules large, much longer than the disk. 1. C. grandiflora. 



Ligules scarcely longer than the disk. 2. C. anomala. 



1. C. grandiflora (Nutt.) Kuntze. Perennial, with a woody root and 

 short caudex; stem 1-2 dm. high, branched, puberulent; leaves linear, more or 

 less distinctly 3-nerved, impressed-punctate, scabrous-hispidulous, 2-3 cm. long; 

 heads solitarj-, short-pedimcled; involucres 6-9 mm. high; ligules yellow, turning 

 whitish, 12-15 mm. long; disk-corollas dark brick-red. Zinnia grandiflora Nutt. 

 Plains: Tex. — Kans. — Colo. — Ariz. Son.- — Submont. My-S. 



2. C. anomala (A. Gray) Kuntze. Perennial, with a woody rootstock and 

 short caudex; stems numerous, 1-1.5 dm. high, puberulent; leaves Unear, 2-3 

 cm. long, one-nerved or 3-nerved at the base, punctate and hispidulous-scabrous; 

 involucres fully 1 cm. high, 5-7 mm. broad; ligules short and rounded, 5 mm. 

 long or less, yellow or orange, often lacking; disk dark brick-red. Plains: Tex. — 

 Colo. — n Mex. Son. Ap-Au. 



65. HELIOPSIS L. Ox-eye. 



Perennial or rarely annual, leafy-stemmed herbs. Leaves opposite, petioled, 

 toothed. Heads radiate, corymbose or soHtary. Involucres hemispheric or 

 carnpanulate; bracts nearly equal, in 2-3 series, the outer herbaceous. Recep- 

 tacle conic or convex, chaffy. Ray-flowers pistillate, fertile, with oblong yellow 

 ligules, more or less persistent on the fruit. Disk-flowers numerous, hermaph- 

 rodite, fertile, enveloped by paleae. Stigmas with short conic hirsute appendages. 

 Achenes 3-4-angled, truncate. Pappus none or reduced to a short, 1-4-toothed 

 annular border. 



1. H. scabra Dunal. Perennial, with a short crown and a fascicle of fibrous 

 roots; stem 5-15 dm. high, more or less hispidulous-scabrous; leaf -blades ovate 

 or subcordate, 5-10 cm. long, scabrous-hispidulous, strongl}^ veined, triple- 

 nerved, coarsely dentate; involucres 8-12 mm. high, 15-25 mm. broad, canes- 

 cent; bracts oblong, obtuse, in 2 series, the outer usually longer; ligules 15-25 

 mm. long. Dry soil and river banks: Me. — N.Y. — N.M. — B.C. Plain — Sub- 

 mont. 



66. BRAUNERIA Neck. Purple Cone-flower. 



Perennial caulescent herbs. Leaves mostly alternate, entire or toothed. 

 Heads radiate, sohtary or few, mostly long-peduncled. Involucres rather flat; 

 bracts in 2-4 series, narrow, herbaceous, squarrose. Receptacle hemispheric, 

 chafTy. Ray-flowers several, neutral, with rudimentary styles; ligules spreading 



