1 18 



accident some 15 or 20 years ago and the top got knocked off, since 

 then the stem has gradually died down. Till about 5 years ago it 

 produced one or two shoots with leaves occasionally, which died 

 away as the decay from above reached them, but for above five years 

 it has not borne any leaves at all. The base of the trunk where 

 it is alive, 2 feet high, contains a good quantity of latex and the 

 stem was tapped some few weeks ago and gave 3J ozs. of very good 

 and strong rubber. The tree still contains latex. The curious thing 

 is that latex is apparently produced by a tree which has not borne 

 leaves at all for a great many years. This seems to show that the 

 latex in a tree is not produced by the action of the leaves, and that 

 a tree can go on producing latex without them. In another case 

 a tree had been cut down to the level of the ground, after many 

 years was dug up, only one large root remained alive and a small 

 part of the trunk which had long been buried beneath the ground. 

 Here again abundant latex was found in the surviving root. 

 Naturally as long as there is any life in the cambium layer there 

 is some amount of growth going on, and probably latex is being 

 produced as long as growth continues. It is not I think probable 

 that the latex in these two stumps has been preserved in the tree 

 in good condition for 10 to 15 years since the main part of the tree 

 and all its leaves have been destroyed. 



H. N. RIDLEY. 



FURNACE FUMES AND VEGETATION. 



The injurious effects on vegetation of the fumes emitted by the 

 tin ore roasting furnaces have been causing some anxiety in some 

 planting areas in Federated Malay States. In one case a large 

 number of Ficus Elastica trees were practically defoliated by the 

 presence of these fumes. Different species of trees are affected to 

 a greater or less degree. The Inga Saman tree of all trees growing 

 in the vicinity of these furnaces is the first to show signs of the 

 ill effects and is most affected. In the case of a large number of 

 such furnaces at Sungei Besi the Inga Saman trees are almost 

 defoliated at a distance of more than 2 miles from the chimneys. 



The Director of Agriculture has erected in the grounds near the 

 Laboratories a model roasting furnace in order to observe exactly 

 the effects caused on rubber trees and other plants. This furnace 

 will have attached to it a condensing apparatus to extract from the 

 fumes the Arsenic and Sulphur which are the cause of the injury to 

 the vegetation. 



J. B. C. 



COCONUT TREE PEST. 



An outbreak of Nettle grub caterpillars, a species of T/iosea, oc- 

 curred on coconut palms in March in Selangor. These caterpillars 

 are of light apple green with bright colored markings and are from 



