F. T. Brooks 223 



general use at the present time, burrs will probably be less troublesome 

 in the future than in the past. The larger type of burr is difficult to 

 treat but good results appear to have been obtained on some estates 

 by using a plane to make the surface smooth after removing these 

 irregular excrescences. 



10. Thread Bliijhl. 



A white thread blight is of common occurrence on rubber trees in 

 Malaya but it causes little harm. The mycelial strands of this fungus 

 vary considerably in size and run long distances over the branches, 

 matting the finer twigs and leaves together and sometimes enveloping 

 the leaves with a fine felt of hyphae causing them to die. The 

 fungus is conspicuous and should be cut out before it has had 

 time to do any considerable harm. This white thread blight is very 

 variable in character and it is possible that more than one species 

 of fungus is involved. Thread blights rarely fructify and there is at 

 present only one record of a fruiting stage in Malaya observed by 

 Richards (12) who sent the fungus to England for identification. It 

 was named Cyphella Heveae by Massee and is thus a member of the 

 Thelephoraceae. Thread blight is of common occurrence on other 

 cultivated trees in Malaya. 



1 1 . Phyllostida rami cola, Petch. 



This fungus affects young green twigs of Hevea brasiliensis and 

 sometimes affords opportunity for the entrance of Botryodiplodia 

 iheobromae as pointed out by Richards (12) and Bancroft (i). It occurs 

 more frequently on trees one to two years of age than on older ones 

 and is usually most abundant towards the end of the year when the 

 rains are heaviest. The fungus generally enters the twig at one or more 

 of the leaf axils 6 to 18 inches below the apex, the fungus probably 

 beginning the attack in the leaf axils because moisture is retained 

 here better than elsewhere. The first sign of its development is the 

 appearance of small brown patches which spread upwards and down- 

 wards causing first a blackish and then a brownish discoloration of 

 the stem. At the same time enormous numbers of pycnidia scarcely 

 visible to the naked eye are formed on the discoloured parts. The disease 

 spreads rapidly downwards and as much as 3 feet of the stem may 

 be killed in the course of a week. The extremities of the affected twigs, 

 which are often not invaded by the fungus, die in consequence of the 



