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 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 Thosea, oc- 
curred on coconut palms in March in Selangor. These caterpillars 
are of light apple green with bright colored markings and are from 
