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IMPORTANT FAMILIES OF PLANTS 



SUNFLOWER OK COMPOSITE FAMILY (cOMPOSITyE) 



This is one of the hirgest families of the flowering plants. 

 It is characterized by nnmerous small flowers growing in a close 

 head. These flowers are either polygamous or monojcious. The 

 ovary is inferior and the calyx tube is attached to it ; the corolla 

 is five cleft, either tnbnlar or strap-shaped ; stamens five, attach- 

 ed to corolla ; anthers united into a tube surrounding the two- 

 cleft style. In most plants the central or disk flowers are 



Fig. 140. — Sunflower, showing the composite flower head. 



tubular and the marginal flower strap-shaped, but in some 

 plants all of the flowers are of the same kind. 



This 'family includes some few plants used for food, such 

 as the Jerusalem artichoke (Helianthus tuherosus L. ), lettuce 

 (Lactuca sativa), some few others that are used in medicines, 

 and a large number that are used for ornamental purposes, 

 such as the sunflower {Helianthus annuus) (Fig. 140), the 

 daisy and chrysanthemum (Chrysanthemum carineum), gold- 

 enrods (Solidagos), asters, dahlias and others. 



