134 



ELEMENTS OP BOTANY. 



most showy anthodia like the sunflower and the daisy there 

 are two kinds of flowers, the ray-flowers, around tlie margin, 

 and the tubular disk-flowers of the interior of the head. This 

 kind of cluster is well illustrated by Fig. 110. The early 

 botanists supposed the whole flower cluster to be a single 

 compound flower. This belief led to their naming one family 

 of plants Compositoe, that is plants with compound flowers. 

 In such anthodia as those of the thistle, the cud-weed and the 

 everlasting there are no ray-flowers, and in others, like those 



Fig. 110 . — Vertical Section of Anthodiuiii of a Suiiflow^er (diagram). 

 inv., involucre; ray^ ray-iiower ; tu.-Ji., tubular flowers of disk; r., common 



receptacle. 



of the dandelion and the chicory, all the flowers are ray- 

 flowers. 



168. Compound Flower-Clusters. — If the pedicels of a 

 raceme branch, they may produce a compound raceme, or 

 panicle, like that of the oat (Fig. 111).^ Other forms of 

 compound racemes have received other names. 



An umbel may become compound by the branching of its 



1 Panicles may also be formed by compound cymes, see § 165. 



