IOWA ACADEMY OF SCIENCES. 249 



55U. S. Jacinidtinn L. Gum weed; Rosin weed; Com- 

 pass plant. Common on prairies. The leaves 

 greedily eaten by horses and cattle. 



Heliopsis Pers. Ox-eye. 



%(). IJ. sni1>r(i Dimal. Woods and prairies; very com- 

 mon. 



liUDBECKLA L. 



561. R. Iiirfa L. Black Eyed Susan. Common on 



prairies, and in timothy fields as a weed. 



Hatibida Kaf. 



562. R. pinnata (Vent.) Barnhart. (Lejiaehi/.s j)i)inafa 



Torr. and (iray.) Very common on dry prairies. 



Brauneria Neck. 



563. B. pallida (Nutt.) Britton. (EcJiuiarea am/usti- 



folia DC.) Common on dry prairies. 



Helianthus L. 



564. //. annuus L. Common vSunfiower. Rare in waste 



places; introduced from Europe. 



565. TL jnaximUiani Schrad. Common on prairies, and 



as a weed in cultivated fields. 



566. //. f/ros.se-serratns Martens. Very common in low 



ground, and our most troublesome species in 

 cultivated fields. All the species of sunflower 

 growing in fields are indiscriminately called 

 rosin-weeds by the farmers. 



567. H. scaherrimx.s Ell. (//. rigidas Desf.) Very com- 



mon on dry prairies. 



568. H. stnunosHs L. Rare in woods; Iowa Lake and 



Armstrong (Irove. 



569. 11. tuherosiis L. Wild Artichoke. Woods and 



prairies; infrequent. 

 Coreopsis 1j. 



570. C. pahnata Nutt. Tickseed. Common on dry 



prairies. 

 BiDENS L. 



571. B. Im-is (L.) B. S. P. (B. chnjmnthenwides 



Michx.) Large Bur-marigold. Margins of lakes 

 and ponds; frequent. 



