Sect. III. GREAT CHAGOS BANK. 55 



structure ! We shall hereafter have to consider both 

 the cause of its submerged condition, a state common 

 to other banks in the group, and the origin of the 

 singular submarine terraces which bound the central 

 expanse ; these, I think it can be shown, have resulted 

 from a cause analogous to that which has produced the 

 bifurcating channel across Mahlos Mahdoo, 



