462 
The trees die in the ordinary way that they do from other root 
diseases, the leaves wither and fall off and the whole tree dies. The 
characteristic feature of the fungus is seen on digging up the roots, 
which, and especially the top root, are encrusted with a mass of 
stones, earth, and sand. This is cemented to the root by the mycelium 
which consists of tawny brown threads collected here and there 
into nodules. The mycelium in a young stage brown becomes black 
later forming a continuous black layer over the brown masses of, 
hyphae (The brown mycelium coating has a shining appearance and 
suggests a thin layer of brown plush, whence here we call it the brown 
plush fungus). On scraping away the fungus, the bark is found to be 
decayed and usually coloured brown ; the wood, if affected, is yellow, 
but this depends to some extent on the tree attacked. In Hevea it is 
usually discoloured and rotten, and wedges of decayed tissue brown 
and powdery, are seen penetrating to the centre from the outside (In 
a specimen of Hevea root sent to the editor some years ago the wood 
was not altered but remarkably dry and hard, as if it had lost all its 
water by drying). 
The fructification is rarely met with. It consists of a patch of a 
finely velvety appearance covered with minute projecting bristles. It 
ppears not to be produced till the tree has been long dead. 
In Ceylon it appears that nearly all the Heveas attacked have 
been planted in old Cacao land which had been cleared lor planting 
Hevea, as Cacao is the tree most affected by Hymenochaete. That the 
growth of the fungus is slow is evidenced by the fact that in a row of 
Heveas fourteen feet apart, and eight years old, one tree having been 
affected and died, it was two years before the next in the row suc- 
cumbed, and another two years before the third in the row died. 
A root fungus with so slow a progress as this should easily be 
cleared out if it appears. To dig out the diseased tree completely and 
fork in lime would probably prevent any further danger. 
Mr- Petch gives figures of a shrub and a Hevea root attacked by 
Hvmenochoete, showing the characteristic clinging of the sand. He 
also mentions and figures a curious destruction of timber by another 
species, Hymenochete rigidula, in which the wood in decay has remark- 
able honeycombed appearance. This I have found in our forests 
rarely, chiefly in Seraya timber (Shorea) which has Iain rotting in 
wet spots. 
Sphoerostilbe repens B. and Br. This parasite on Hevea roots has 
been found in about a dozen cases killing Para Rubber in Ceylon. In 
most cases it seems to have attacked trees in swampy soil, but has 
killed trees in average plantation soil. In the first noticed case three 
trees in a patch of undrained sour soil between a set of coolie lines 
and a factory where the surface roots were constantly being damaged 
were killed. The ground was used for storing firewood and probably 
the fungus was brought in on jungle billets. It occurs up to 2,000 
feet in Ceylon. The mycelium is easily recognised. When the root is 
