IOWA ACADEMY OF SCIENCES. 
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559. S. laciniatum L. Gum weed; Rosin weed; Com- 
pass plant. Common on prairies. The leaves 
greedily eaten by horses and cattle. 
Heliopsis Pers. Ox-eye. 
560. H. scabrci Dunal. Woods and prairies; very com- 
mon. 
Rudbeckia. L. 
561. R. hi via L. Black Eyed Susan. Common on 
prairies, and in timothy fields as a weed. 
Ratibida Raf. 
562. R. pinnata (Vent.) Barnhart. (Lep achy s pinnata 
♦ Torr. and Gray.) Very common on dry prairies. 
Brauneria Neck. 
568. B. pallida (Nutt.) Britton. ( Echinacea angusti- 
folia DC.) Common on dry prairies. 
Helianthus L. 
564. II. annaus L.. Common Sunflower. Rare in waste 
places; introduced from Europe. 
565. II. maximiliani Schrad. Common on prairies, and 
as a weed in cultivated fields. 
566. II. grosse-serratus 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. scaberrimus Ell. (II. rigidus Desf.) Very com- 
mon on dry prairies. 
568. II. strumosus L. Rare in woods; Iowa Lake and 
Armstrong Grove. 
569. II. tuberosus L. Wild Artichoke. Woods and 
prairies; infrequent. 
Coreopsis L. 
570. C. palmata Nutt. Tickseed. Common on dry 
prairies. 
Bidens L. 
571. B. Icevis (L.) B. S. P. (B. chrysanthemoides 
Michx.) Large Bur-marigold. Margins of lakes 
and ponds; frequent. 
