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 serve to show how 

 the members of clusters are distributed in an all-sided manner 

 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 

 faces are differently condi- 

 tioned, the flowers are all on 

 the outer face : 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 which other types present, may be 

 & 161 



