4 THE CORAL REEFS OF THE MALDIVES. 



Fulidu Channel, 374 fathoms. The greatest depth between Goifurfehendu 

 and South Malosmadulu is 302 fathoms, that of North Kardiva Channel, 

 372 fathoms. From South Malosmadulu the central basin dips from 236 to 

 519 fathoms, and between Fadiffolu and Miladummadulu the greatest depth 

 is 769 fathoms. 



The groups which constitute the western and eastern chains of the 

 central Maldives (PI. 1) are elevations of considerable size ; they form the 

 rim of an inner basin. The channels between the groups both on the east- 

 ern and western faces of the basin correspond as far as we know very nearly 

 in depth with those of the nearest part of the central basin. 



Our soundings (PI. 1) indicate that Kolumadulu is on the southern ex- 

 tremity of that part of the plateau of the Maldives which extends unbroken 

 from Ihavandiffulu south to Kolumadulu, or rather of a plateau of which 

 the undulations are nowhere separated by depths greater than three hun- 

 dred fathoms ; although between Fadiffolu and Miladummadulu a tongue 

 of deeper water projects to the westward a considerable distance towards 

 North Malosmadulu. 



South of Kolumadulu the conditions are different ; Haddummati, Suva- 

 diva, and Addu occupy small plateaus separated by considerable depths 

 and distinct from the larger one to the north. Haddummati, although less 

 than twenty miles south of Kolumadulu, is divided from the northern 

 plateau by a channel over eleven hundred fathoms in depth (PI. 1). 

 Suvadiva rises from depths of over eleven hundred fathoms in the One 

 and half degree Channel, fifty-five miles in width, which separates it from 

 Haddummati ; and finally the small plateau of Addu, forty-five miles south 

 of Suvadiva, rises from depths of nearly thirteen hundred fathoms, indi- 

 cated in the central part of the Equatorial Channel. 



