CYMES 



123 



194. Compound umbel of 

 wild carrot. 



sometimes open and loose. 

 These flower-clusters are known 

 as cymes. Apples, pears (Fig. 

 196) and cherries bear flowers 

 in cymes. Some cyme -forms 

 are like umbels in general ap- 

 pearance. A head-like cymose 

 cluster is a glomerule: it blooms 



from the top downwards rather than 

 from the base upwards. 



258. Centripetal and Centrifugal. — 

 A cluster in which the outermost 

 (or lowermost) flowers open first is 

 corymbose or indeterminate, as we 

 have learned; it is also said to be 

 centripetal (meaning "toward the cen- 

 ter"). A cluster in which the inner- 

 most or central flowers open first is 

 cymose or determinate; it is also said 

 to be centrifugal (meaning "away from 

 the center"). These contrasts can 

 best be under- 

 stood by study 

 of diagrams, 

 since actual 

 clusters so often 

 vary from the 

 assumed stan- 

 dard. Such diagrams are presented in 

 Figs. 197, 198, 199. 



259. Mixed Clusters.— Often the 19G - Cyne of pear 



cluster is mixed, being determinate in one part and indeter- 

 minate in another part of the same cluster. This is the case 

 in horse-chestnuts. The main cluster is indeterminate, bu1 

 the branches are determinate. The cluster has the appear- 



195. Determinate or cymose 

 arrangement. — Wild geranium 



