180 CAMPANULALES 



Achenes compressed and winged. 



Receptacle columnar to subulate, leaves divided or parted. 



5. Ratibida. 

 Receptacle convex or conic, leaves serrate, decurrent on the 

 stem. 8. Verbesina. 



Involucral bracts imbricated in 2 series, the inner membranous, very- 

 different from the outer in texture, rays yellow or none. 

 Inner bracts distinct or slightly united at the base, rays sometimes 

 lacking. 

 Pappus of 2-5 downwardly barbed awns or teeth, outer bracts 

 often as long or longer than the inner, rays often lacking. 



10. Bidens. 

 Pappus not downwardly barbed, the outer bracts very small. 



9. Coreopsis. 

 Inner bracts united to about the middle, the outer much smaller. 



11. Thelesperma. 



1. Silphium. 980. 



Leaves opposite or the upper alternate. 



Stems square, leaves perfoliate. 1. S. perfol latum. 



Stems round, leaves not perfoliate. 2. S. integrifolium. 



Leaves all alternate, the basal pinnatifid. 3. S. laciniatum. 



1. Silphium perfoliatum L. Rosin-weed. 



In wet soil in the eastern part of the state. Indianola; Lincoln; Ne- 

 braska City; Turner; Wahoo; Walton; Wymore. 



2. Silphium integrifolium Michx. Rosin-weed. 

 Common in prairies in the eastern part of the state. Franklin; Lin- 

 coln; Nebraska City; Newark; Plainview; Red Cloud; Wahoo; Wy- 

 more. 



3. Silphium laciniatum L. Compass-plant. 

 Common in low prairies in the eastern part of the state. Foster; 

 Fremont; Lincoln; Nebraska City; Weigand; Wymore. 



2. Heliopsis. 984. 



1. Heliopsis scabra Dunal. False Sunflower. 



Common in the eastern part of the state. Arapahoe; Callaway; Grand 

 Island; Nebraska City; Niobrara; Wahoo; Valentine 



3. Eclipta. 984. 



1. Eclipta alba L. 



Along streams in the southeastern part of the state. Crete; Lincoln. 



4. Rudbeckia. 985. 



Hispid; leaves sparingly serrate or entire. 1. R. hirta. 



Glabrous or nearly so; lower leaves pinnately parted or pinnatifid. 



2. R. laciniata. 



1. Rudbeckia hirta L. Black-eyed Susan. 



A common weed in the eastern part of the state. Aten; Cherry Coun- 

 ty; Lincoln; New Helena; Nebraska City; Newark; Pine Ridge; 

 Plainview; Plummer Ford; Valentine. 



