Fig. 100. Phylogenetic trends in i\o\vcv patterns correlated witli mntualistic 

 evolntion after insect pollination became established. Roman nnmerals indicate 

 levels of general type of flower adaptation: I, amorphons; II, blobs of color; 

 III, radial design; IV, differentiation of shapes within the radial design; V, evo- 

 lution of specialized shapes; \'I, eNolution of specialized types including non- 

 radial types (bilateral s>mmetry as in 5, 8, and 14) and return to an over-all 

 radial design in heads containing many individual flowers (as in 11). Phy- 

 logenetic trends which can be assumed are indicated by arrows. (After Lep- 

 pick. ) 



