2o; 



commonly on dead parts of Hevea, similarly to Nectria diversispora. 

 It takes the form of pin-like structures, about ^0 of an inch long, 

 each consisting of a red stalk and a rounded pink head. The spores 

 germinate readily in a i% solution of cane sugar and reproduce a 

 white mycelium. Pure cultures were obtained from the spores on 

 agar-agar and a 10% extract of the juice of the sugar cane. The 

 mycelium grows somewhat rapidly, a good growth being obtained in 

 a week. Both the mycelium obtained in the pure cultures and the 

 spores taken from the "heads" of the fruits were used to inoculate 

 ten-year-old trees through cuts which were made on the two-months- 

 old tapping surface. The cuts were of the same two types as in the 

 previous experiments ; and three cuts of each kind were made on 

 each of four trees. At the end of nine weeks an examination showed 

 no signs of disease ; while the dead portions of the outer bark, which 

 had been severed in making the wounds, were observed to bear the 

 conidiophores of the fungus, thus shewing clearly its saprophytic 

 nature. 



Both of these fungi have been found to be associated with an 

 effect on the tapping surface, which at first appeared to be patholo- 

 gical, but which on further investigation was found to be only tem- 

 porary. This effect has been recorded here and there in isolated 

 cases on several plantations, and on one plantation it was present in 

 some abundance on trees of seven and ten years ; it has also been 

 recorded in Ceylon. The newly tapped surface shows it first ; here 

 sunken patches make their appearance externally and an exami- 

 nation shows that the bark, which should be renewing, is dead. If 

 the dead bark be removed the wood beneath it is found to be dis- 

 coloured, and the area of discoloured wood is greater than the exter- 

 nal surface of dead bark would indicate. The dead area increases in 

 size and the tapped surface may be affected for the whole length of the 

 tapping cut and for a vertical distance of one or one-and-a-half 

 inches. The effect may occur separately on either of the cuts or it 

 may occur simultaneously on all the cuts. After a time the wounds 

 commence to heal over and the effect, which is, therefore, only 

 temporary, is remedied. There may be, however, considerable damage 

 done by the entrance of boring insects on the dead bark. On the 

 outer, dead bark, a white mould composed of the two conidial forms 

 of Nectria dlversispora frequently occurs, as also do the sporophores 

 of Stilbella Heveae. 



Repeated attempts to inoculate with the organisms present in 

 the dead tissues have failed ; these, in addition to the two fungi given 

 above, are species of Penicillium and Aspergillus and two kinds of 

 bacteria. The fact that the trees are capable of healing after a time 

 is sufficient evidence to show that the initial effect is not due to a 

 parasitic micro-organism. The death and decay of the wood is in all 

 probability due to the entrance and percolation of water containing 

 organisms of decay ; and it seems probable that the death of the newly 

 tapped bark at the* commencement is due to the presence of ah excess 

 of water oh the tapping surface. In Ceylon, the effect has dnly been 



