GLACIAL-CONTROL THEORY OF CORAL REEFS. 



191 



Though the conditions aflfecting these oceanic areas are, and long 

 have been, highly variable, it is instructive to note the relation of the 

 maximum depth to width of the platform. Average values for the 

 two elements have been computed and the results given in Table II. 

 Similar averages for general depths on banks and in the deeper parts 

 of lagoons are also there entered. 



