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fungi, such as the little scarlet Polyporus igneus and Schizophylhun 

 xommune that only attack dead and old timber, beams of houses, etc, 

 but I have never seen Fomes semitostiis doing so. I have seen it on 

 other trees besides Hevea but always on just dying trees, not on long 

 dead timber. In the Botanic Gardens, we often have, after a tree 

 killed by fungus, a number of its roots left in the ground where these 

 are exposed as in a drain, the cut ends producing the fructification of 

 Fomes. Often in abundance each root bears the characteristic white 

 strands. Wood, however, not affected in the first instance by the 

 white fungus, if left lying on this ground, does not produce Fomes. 



Strands of mycelium on or near Para roots have been sent to me 

 which are different in colour from the white mycelium strands always 

 associated with Fomes. A pink strand has been several times sent 

 usually from new cleared land and also an orange yellow one. These 

 may belong to some other fungus. There may, of course, be other 

 fungi on rubber trees which have white mycelium in strands, which 

 mycelium might be mistaken for those of the Fomes, but the char- 

 acteristic white bands which causes the death of the Para rubber tree 

 and which are well figured by M. Vernet, I think, there can be no pos- 

 sible doubt belong to the Fomes. 



Directions are given by M. Vernet for checking the disease in the 

 ways already published in the Bulletin and commonly in use. 



2. Corticium javanicum : this is also described. M. Vernet notes 

 its very rapid appearance on occasions sometimes as quickly as in 

 one night, after long and heavy rain. He discusses the relationship 

 of the little beetles xyleborus parvulus and Ptorelophia melanura and 

 gives evidence that the xyleborus (shot borer) can penetrate the 

 living bark of a Para rubber tree without being killed by the latex, 

 and even thick layers of coal tar, and alleges that the statement that 

 they are killed by the exudation of latex is due to an error of 

 observation, and that they die naturally in the mouths of their 

 burrows. This might be so, but we have seen in a case of attack of 

 shot borers in a dead piece of Hevea, a large number which attemp- 

 ted to escape lower down through the living bark stuck and imbed- 

 ded in latex. However, one species may be able to make its way 

 through ths latex while another cannot. 



The connection of Corticium with these beetles is this. They live 

 in parts of the tree attacked by Corticium and when flying away as 

 .adults can carry the spores to other healthy trees. It seems difficult 

 for the mycelium of Corticium to penetrate the bark of Hevea except 

 in cases where the bark is already wounded and it is suggested that 

 this is effected by the burrowing of these beetles. 



Corticium does not seem to be nearly so common as a pest in the 

 Malay Peninsula as in Java and Borneo, though in rainy weather it 

 is very common in Singapore in Ramie, Strobilanthes and other 

 shrubs. The specimens I have received of Hevea attacked by Corti- 

 cium were not attacked by the shot borer, still the point is worthy of 

 notice. That shot borers have certainly peculiar habits. Not long 



