RHIZOPHORACEAE 



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there are further large stretches of mangrove both north and south of Mergui 

 along the coast and round the islands. 



The natural orders and the principal species which make up the mangrove 

 formations of the Indo-Burman region, and the localities in which they are 

 known to occur, are given in the following tentative table : 



Distribution of mangrove swamp species in the Indo-Burman region. 



Although the species mentioned in this table occur in the mangrove 

 swamps, some of them are by no means confined to them, and may extend to 

 the drier ground farther inland. 



Characteristics of mangrove swamps. Mangrove swamps are formed 

 on the silt which is washed down by rivers and creeks, and which, subject to 

 occasional erosion, gradually spreads seawards, the mangrove spreading with 

 it and helping, by means of its dense growth and mass of roots, to hold up the 

 silt and form new land. As the silt accumulates the ground graduallj'^ rises 

 and becomes drier, and an entirely new formation replaces the mangrove ; 

 this formation occurs on land which is inundated only by spring tides, and 

 is commonly known as tidal forest. The most important Indian species of the 

 tidal forest is the sundri (Heritiera Fomes). Although some of the species of 

 the mangrove swamp extend into this forest many new species appear. The 

 mangrove formation extends up rivers sometimes for miles, and is usually 

 intersected by numerous creeks, Avhich are often dry at low tide but can be 



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