ARRANGEMENTS OF FLOWER PARTS. 22$ 



flower is said to be eptgynous, as in the evening primrose. 

 When the stamens or petals are borne on the calyx, the flower 

 is said to be perigynous, or the stamens are said to be perigy- 

 nous, as in the cherry (fig. 229), apple, etc. The flower is 

 hypogynous when all the parts of the calyx, corolla, and andrce- 



Fig. 196. 

 The bluet (Houstonia ccerulea). 



cium are free in their insertion, that is, when they are inserted 

 on the receptacle, "under the pistil," since the pistil termi- 

 nates the floral axis (example, the buttercup, etc. ). 



367. Floral Formula. A formula is sometimes written to 

 show at a glance the general points of agreement in the flower 



