CHAPTER XXII 



DISPERSAL OF SEEDS 



273. Explosive fruits of 

 oxalis. An exploding 

 pod is shown at c. The 

 dehiscence is shown at 

 6. The structure of the 

 pod is seen at a. 



300. It is to the plant's advantage to have its seeds 

 distributed as widely as possible. It has a better chance 



d of surviving in the struggle for exis- 

 tence. It gets away from competition. 

 Many seeds and fruits are of such 

 character as to increase 

 their chances of wide dis- 

 persal. The commonest 

 means of dissemination 

 may be classed under four 

 heads : explosive fruits ; 

 transportation by wind ; 

 transportation 1>ij birds ; 

 burs 



301. EXPLOSIVE FRUITS. Some pods 

 open with explosive force and scatter the 

 seeds. Even beans and everlasting peas (Fig. 



246) do this. More marked 



examples are the locust, 



witch hazel, garden balsam, 



wild jewel weed or impa- 



tiens, violet, and the oxalis J 1 



(Fig. 273). The oxalis is 274. winged seeds 



i of catalpa. 



common in several species 

 in the wild and in cultivation. One 

 of them is known as wood -sorrel. 

 Fig. 273 shows the common yellow 

 oxalis. The pod opens loculicidally. 



(158) 



275. 



Wind-blown fruits 



of dandelion. 



