COAST LINES 



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the coast itself are often found near, separated from it 

 only by shallow arms of the sea. These are evidently 

 a part of the adjacent mainland with a submerged portion 

 between. 



Sometimes in warm latitudes where conditions are suit- 

 able, the coast is bordered for a long distance by coral 

 reefs. The northeast coast of Australia affords a marked 



NORTH CAPE. 

 A famous promontory which defies the waves of the North Atlantic. 



example. Here a barrier reef extends for a thousand 

 miles along the coast, protecting it and leaving a smooth 

 water channel 10 to 30 miles broad for coastwise naviga- 

 tion. 



A coast in warm regions may also be protected by 

 the growth of dense thickets of mangroves. This tree 

 grows in shallow water and sends down from its branches 

 roots upon which crabs and oysters live and among which 



