STUDY OP FRUITS AND SEEDS. 



245 



Dispersal by Plants themselves. 



The commonest case is by the sudden splitting of the 

 dry carpel (explosive fruits), by which means the seeds are 

 thrown some distance away. This is quite audible in some 

 cases, e.g. Broom. Violet seeds are also scattered in this 



PERSISTENT 

 CALYX 



Fig. 123. Capsular fruit of Stitch wort, 

 which splits lengthwise into a num- 

 ber of teeth at top, permitting the 

 seed to escape when the plant is 

 shaken by the wind. 



VALVE 



Fig. 124. Fruit of Poppy 



(Capsule). 



The seeds are shaken out 

 through the pores. 



way. In Geraniums the style splits into a number of one- 

 seeded pieces (Fig. 120), curling up and throwing out the 

 seeds. In other cases the seed vessels split open and the 

 seeds are shaken out by the wind. Pods, Follicles, Cap- 

 sules (Figs. 119, 121 to 124). 



Dispersal by Water. 



This occurs chiefly in connection with water plants, in 

 which case there is sometimes a special adaptation, e.g. in 

 the Water Lily (Nymphaea) there is a growth (arillus) 

 outside the seed coat, and between these an air chamber 



