228 THE REPRODUCTIVE ORGANS 



(2) The turgidity of part of the fruit-coat or seed is 

 the means of expelling many seeds. Interesting examples 

 to observe are the Wood Sorrel (7) and the Balsam (8). In 

 the former each seed has a fleshy aril, the inner layer of 

 which is very turgid. If the ripe fruit is disturbed, the 

 capsule splits, the aril suddenly turns inside out, and 

 the seeds are shot some distance. If the ripe fruits of the 

 Balsam are lightly pressed between the fingers, the fruit- 

 coat splits and the valves roll up inwards with great force, 

 scattering the seeds in all directions. 



