REPRODUCTION. 



221 



Among the Umbelliferce as well as the Composite the flowers of 

 the same inflorescence (umbel, head) are often different ; the central 

 ones are actinomorphic and the peripheral ones zygomorphic. 

 Among the Composites there are distinct strap-shaped and tubular 

 flowers, or even two-lipped flowers, in place of the former. Fig. 

 146, &, shows the involucre of hypsophyllary leaves ; m, a tubular 

 bisexual flower; /, a sterile two-lipped marginal flower; J, the 

 receptacle; M, a hypsophyllary leaf; f, ovary; <?, style with 

 stigma; sf and sb, filaments with united anthers. The Umbelliferce 

 are distributed through the temperate zone and comprise about 



FIG. 147. Aethusa cynapium. 

 a, Umbel; c, flower; e, fruit; /, cross-section of the fruit; g, leaf. (After Krass and Landois.) 



1300 species (Eichler). Figs. 147-149 are given to represent the 

 general characteristics of this family. 



The dicotyledons are now usually divided into Choripeialoe and 



