HI.] CRUCIFER^E. 63 



Hildebrand never saw an insect on the flowers. 

 H. Miiller saw them occasionally visited by the honey 

 bee. In F. officinalis, as in C. cava, the anther cap is 

 elastic, and on the departure of the insect resumes 

 its original place. It is interesting that in other 

 species of each genus (none of which however are 

 English), as for instance C. ochroleuca and F. spicata, 

 the pillar formed by the stamens and pistil is in a 

 state of tension, but is retained in its place by the 

 two petals forming the cap. These are as it were 

 locked together, but when once separated by the pres- 

 sure of the bee, the pillar formed by the stamens and 

 pistil is set free, and springs up, thus dusting the 

 insect. This process only happens once in each 

 flower. Though these species are not British, I men- 

 tion this here, because we shall find a very similar 

 process in some of the Leguminosae (p. 86), and it is 

 most interesting to find such a remarkable arrange- 

 ment thus repeated in very different groups. 



CRUCIFER^:. 



4 



The Wallflower, Stock, Cabbage, Shepherd's Purse, 

 Watercress, &c., belong to this group. 



The Cruciferse are easily distinguished from other 

 orders by their four sepals and petals, and six stamens ; 

 but the genera into which they are divided are by no 

 means so well marked, and are to a great extent 

 distinguished by differences in the pods and seeds. 

 The general structure of the flower is more or less 

 similar throughout the order, but the number and 

 position of the honey-glands differ in almost every 

 species. Hesperis matronalis is one of those plants 



