COMPOSITE. 



61 



but 59 of these have been introduced from 

 other countries; 237 genera are represented. 

 The largest genus of this family is Senecio, 

 which contains nearly 900* species, only 57 

 of which occur in this country. The largest 

 genus in America is Aster, which comprises 

 124 species, and the next is Solidago, golden- 

 rods, comprising 78 species. 



The members of the Compositae have three 

 easily recognizable peculiarities : the indi- 

 vidual flowers or florets are small and they 

 are compacted into a conspicuous head, which 

 is commonly mistaken for one flower ; the 

 calyx is represented by soft hairs or little 

 teeth borne at the apex of the little fruit ; 

 the anthers are united in a ring about the 

 style. The outer flowers in the head are 

 often furnished 

 with a long ray 

 or notched petal 

 on one side, and 

 these rays ap- 

 pear like the 

 petals of one 

 simple flower. 

 Fig. 49 repre- 

 sents the blue ^^^•*^- 

 flower of an aster with the conspicuous rays 



