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wounded exude a gum, resin or latex which acts as a protection 

 against animal and fungus attacks. 



The protection is by no means always perfect, as insects or fungi 

 occasionally find a way of getting past the barrier. Take for in- 

 stance Castilloa. This plant is here destroyed by the longicorn 

 beetle, Epepseotes luscus. It attacks the plant through the thin spot 

 where a branch has fallen, and where there is little or no latex, 

 once the egg is pushed through into the wood, the larva does not 

 come in contact with the latex but bores, up and down in the wood. 

 The part of the tree attacked by it dies and the beetle can escape 

 through the wood now unprovided with latex. A tree like this is 

 quickly exterminated. The failure of the latex in this case to pro- 

 tect the tree means the total destruction of all Castilloas in the 

 region in which the beetle lives. Besides wood-boring insects we 

 have innumerable fungi which attack dead tissue and can eventually 

 hollow out a tree so that it readily falls. If it is worth while, so to 

 say, for the Oncosperma, and thorny sago to develop thorns to pro- 

 tect their young shoots from the attacks of pigs, or for the Arenga 

 palm to develope the great mass of fibre over the bases of its leaves 

 to keep the rain from running down into the sheaths, surely it is 

 worth while for a tree to develop a laticiferous system, or a series 

 of resin ducts to guard against the common injuries caused by a 

 heavy wmd, or the fall of a tree near it. 



I would not suggest this as the only function of latex, but rather 

 that it is one of the utmost importance to the life of the plant. 



The Conditions in Para. 



It has been pointed out by WlCKHAM, says Mr. WRIGHT that the 

 true forests of the Para rubber trees lie back on the highlands and 

 those seen by travellers along the river-side are scattered and poor in 

 growth and do not give one a fair idea of the conditions under which 

 a good growth of the Hevea is obtained. On this statement appa- 

 rently an idea got about that Para rubber should not be grown on 

 the alluvial flat as it is in the Malay Peninsula but in hilly regions. 

 This idea of the Hevea braziliensis growing on hill land has not 

 been confirmed by any of the professional Seringueiros from the 

 Amazons who have visited the Gardens, nor is it at all confirmed 

 by ULE, whom the author quotes. All agree that the lowlying swamp 

 in the Singapore Botanic Gardens exactly resembles the home of 

 the Para rubber, and that the trees have the same form and growth. 

 May it not be that in the districts that Mr. WlCKHAM visited all 

 the best of the trees on the easily accessible river bank had been 

 tapped to death, while those on the more inaccessible highlands had 

 escaped. This is what one would expect to happen. 



Manuring and close planting. — The danger of manuring trees by 

 the system of digging trenches and so cutting through the roots as 

 recommended by Mr. WRIGHT has been already pointed out in the 

 Bulletin, as has the principle of close planting either of Para rubber 

 trees or Dadups or any other trees and then cutting out. No inter- 

 ference with or cutting the roots of a Para rubber tree should be 



