CHAPTER X. 



THE SHAPES OF FLOWERS. 



| 232. FOLLOWING an order like that of preceding chap- 

 ters, let us first note a few typical facts respecting the forms 

 of clusters of flowers, apart from the forms of the flowers them- 

 selves. Two kindred kinds of Leguminosce will serve to show 

 how the members of clusters are distributed in an all-sided man- 

 ner or in a two-sided manner, according as the circumstances 

 are alike on all sides or alike on only two sides. In Hippo- 

 crepis, represented in Fig. 226, the flowers growing at the end 

 of a vertical stem, are arranged 

 round it in radial symmetry. 

 Contrariwise in Melilotus, Fig. 

 227, where the axillary stem 

 bearing the flowers is so 

 placed in relation to the main 

 stem, that its outer and inner 

 sides are differently condi- 

 tioned, the flowers are all on 

 the outer side : the cluster is 

 bilaterally symmetrical, since 

 it may be cut into approx- 

 imately equal and similar 

 groups by a vertical plane passing through the main axis. 



Plants of this same tribe furnish clusters of intermediate 

 characters having intermediate conditions. Among these, 

 as among the clusters whicn other types present, may bo 



