92 



AUSTRALASIA. 



region of the Musi delta has been formed during the historic period. Even the 

 city of Palembang, now lying in the interior far above the estuary, is said to have 

 been originally founded on the coast itself at the mouth of the river. The man- 

 groves, by which these low-lying tracts are overgrown, contribute to the enlarge- 

 ment of the dry land by arresting the sedimentary matter amid their branches, 



Fig. 33.— Alluvial Plains of the Musi Basin, 

 Scale 1 : 4,000,000. 



77^ 







Depths. 



Old Shore-line. 



Otol6 

 Feet. 



16 Feet and 

 upward?. 



Recent formations. 



.60 Miles. 



and by shedding their fruits beyond the river banks in the muddy waters, where 

 they take root. 



The "West .\xd East Sumatrax Islands. 



West of Sumatra runs a chain of islands disposed parallel with the west coast. 

 Abysses over 1,000 fathoms deep separate this chain from the ]N[icobar Archipelago; 

 but with Sumatra it is connected by the incline of the now submerged intervening 

 slopes. These islands form, so to say, an advanced coastline of the neighbouring 

 mainland, and consist of the same Tertiary formations as those of the adjacent 

 shores. Lying on a marine bed at a mean depth of not more than 50 fathoms, 

 they stand on the very edge of the submarine Indonesian plateaux. Immediately 



