PLANTS THAT BUILD ISLANDS 127 



more favourable conditions than those that produce 

 islands, it is not necesary for them to have so many 

 aerial roots, nor to spread their branches so pro- 

 fusely; so they stand erect, and reach a consider- 

 able height. These trees are covered with myriads 

 of leaves which fall annually and thus build up the 

 land. 



Most plants which build islands such as the sea- 

 rocket, the horned-poppy, and the sea-holly not 

 only love the salt water, but actually like the rough 

 life ; many preceding generations have inured them 

 to such conditions, until now they could not thrive 

 without them. 



