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bulletin: museum of compaeative zoology. 



over its landward edge. In the main the relations of the shore sands 

 to the reef are concealed. From where the reef leaves the shore and 



has water on both sides of it, the landward face in some places is broken 

 off squarely, in others it slopes down gently in steps only a few centi- 

 metres hit^h to low-water level. 



