THE MANGROVE OF THE BOMBAY PRESIDENCY. 645 



flnra, Lumnitzera racemosa, Sonneratia aptala and acida, Can/pa 

 obitvata, Jl\giceras majus, Avicennia officinalis, Acanthus ilicijolhis. 

 Here I should 1 ke to add Excaecaria aualhchu L. (Euphorbiacese), 

 which is not given by Schimper in the above list, but which, with good 

 reason, may find a place amongst the mangrove vegetation. 



In the following description of the several plants it is not my inten- 

 tion to give their complete outer morphology, as there is no want of 

 excellent Floras which describe them fully ;* but what I propose is to 

 give a general idea of their habit, drawing the attention to those 

 characters only which are necessary for the understanding of their 

 biological peculiarities. 



In the broad bolt of mangrove, which may be seen in many tidal 

 creeks and back-waters along the coast of the Presidency and chiefly 

 near tne shallow mouth of rivers still exposed to the high-water of the 

 sea, there is especially one kind which by its curiously spreading aerial 

 roots can easily be recognized as Rhiznphora mucronata, also called the 

 " true mangrove." It is a small, evergreen, glabrous tree or large shrub 

 with thick, terete branches, which are marked with leaf-scars all over. 

 The opposite leaves are entire, coriaceous and glabrous, bright preen 

 above, paler and dotted black beneath. The flowers, which arise 

 from axillary cymes, have white, thick, and fleshy petals with villous 

 margins, and a pale yellow, coriaceous, glabrous calyx. The ovoid- 

 conical fruit is lh in. long and surrounded at the base by the persistent, 

 calyx. RhizopJiora mucronata forms sometimes tangled thickets by the 

 interlacing of its roots, sometimes it is more isolated ; but in any 

 case it always occurs on the outer border of the mangrove formation 

 towards the open sea, thus serving as a protective outpost of the less 

 favoured representatives of the same formation. When the tide is 

 out, the ground occupied by the mangrove shows a blu'sh-blnck mud, 

 from which innumerable short stems and longer roots arise. The 

 " true mangrove " may easily be distinguished from its neighbours by 

 the long aerial roots which raise the main trunk above the level 

 of its origin and give the tree the appearance of being supported on 

 stilts. These arise from the usually short stem on all sides, grow- 

 ing first for a short distance in a horizontal direction and arching 

 down afterwards into the water. Soon the base of the stem, 

 with its original roots, dies and now the only support to the upper 



• Cf. Cooke'e Flora of the Presidency of Eombay. 

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