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Corticium javanicum is a parasite of the bark of the branches and 

 trunk. On Hevea it appears generally on the base of a lower branch 

 or on the trunk hardly as high as the first branches. Trees of various 

 ages are attacked, leading to death, in trees of 1? — 2i years old es- 

 pecially. The first appearance of the parasite is a little rosy or nearly 

 whitish spot on the bark. The spot extends, thickens, takes on a more 

 vivid rose tint, cracks in a characteristic manner, and finally surrounds 

 the branch or trunk attacked. The bark may be crushed with slight 

 pressure of the finger, and big lumps raised off with the finger nail. 

 Observation of the microscopic and macroscopic characters and the 

 results of infection experiments on young Hevea plants prove that the 

 fungus is the same as the parasite which damages coffee plants. 

 Abundant rain and humidity of the atmosphere favour the extension of 

 the fungus. 



The relative abundance of the disease depends too on the age of 

 the plants and the local conditions of soil and air ; some places are 

 more widely affected than others. It is certain that it is contagious ; 

 very often the parasite was noticed to pass from coffee, on which it was 

 abundant, to Hevea planted in the same ground. The remedy is to 

 cut off the infected parts. The debris should not be carried through 

 the plantation, as contamination may take place, but should be care- 

 fully burned on the spot. Of course it is necessary to tar the wound 

 made and all others that may be noticed. In all cases where this 

 procedure has been carefully followed it has given good results. 



(b). White Fungus of the Eoots. This disease appears to be at 

 least as dangerous as the preceding. Plants of different ages, especially 

 from 1 to 2 years, apparently in excellent health, begin to brown at the 

 top, the leaves dry up, become yellow, and fall shortly after. As a 

 planter remarked to the author it is difficult to say at this stage whether 

 it is really disease or only normal leaf -fall. But at a slightly older 

 stage a wound made in the stem yields only a scanty flow of latex, 

 later still the flow ceases completely. A few days later the plant is 

 evidently dead. We notice at once that the external symptons are 

 very striking. The diminution of water in the plant is the first phenom- 

 enon, it manifests itself exteriorly by desiccation of the tendeiest 

 parts — the top of the stem and the young leaves ; later it is the convey- 

 ance of nourishment which is changed, and we see that the elaborated 

 substances like the latex are less abundant. The fungus forms more 

 or less developed cords of a felty consistency, tough elastic and often 

 very thick. At first the cords are are always met on the taproot, 

 which is destroyed and the solidity of the tree so damaged that it is 

 blown over by a puff of wind a little beyond the ordinary. Among 

 young plants the disease has nearly always fatal results. It is all the 

 more serious because, as in most root diseases, it is not noticed until it 

 is too late to apply efficacious measures. In from 10 to 15 days after 

 one is convinced that disease is present the tree dies. 



Neither in the field nor on cultures of good material made in a 

 moist chamber and on various nutritive media, in the laboratory, 

 have I been able to find reproductive organs which would enable me to 

 determine to which group the fungus belongs. 



