PARA RUBBER. 153 



sulphur to four parts of lime. In replanting, the holes should be 

 filled with earth mixed with lime and sulphur in the proportion of 

 one basket of sulphur, four of lime, and seven of soil. This should 

 protect the new plants from any underground attacks. 



Grubs of a large cockchafer (Lepidiota pinr/uis, Burm.) have been 

 received by Green§ from yatiyantota, Ceylon, with the report that 

 they are found about two inches below ground-level. "It is stated 

 that the pest bites through a live stump (of Para rubber) of any size. 

 The only way one can tell that it is working is by seeing the green 

 shoot on the stump die back. On touching the stump it breaks off. 

 Specimens of injured stumps (of about the thickness of a lead pencil) 

 were sent in with the grubs. The taproot has been severed an inch 

 or two below the collar, and every vestige of a side root has dis- 

 appeared. Alkaline manures, such as kainit and nitrate of soda, 

 have been found useful in driving away cockchafer grubs. The 

 manure should be forked in round the plants in clearings affected 

 by the pest. The same species was recorded in 1902 from the 

 Negombo District, where it attacked the roots of cinnamon 

 bushes. The adult beetle is of considerable size, being fully an inch 

 long and proportionately stout. The larva is a white fleshy grub, 

 two inches in length, the body curved round into the form of a 

 horseshoe, ft has very powerful jaws, with which it works ureal 

 havoc on the roots upon which it feeds."' 



•' A formidable looking grub of some large beetle (Buprestid or 

 Longicorn?) has been sent by a correspondent from Ruanwella, It 

 is said to have been found in the taproot of a. rubber tree that had 

 died and broken off. The pest in its larval stage, working— as 

 it does — below ground-level, will be difficult to attack." 



A Disease on Rubber. 



It seems as though enough has been said regarding the troubles of 

 all parts of the plants with fungi and insects, but this note deals with 

 a disease on the prepared rubber and cannot be omitted. The signs 

 of the disease are that the rubber becomes at first stick}' or tacky, 

 and rapidly softens until it is almost liquid. It can be spread from 

 one biscuit to another by contact. It is supposed to be due to 

 bacteria, which first commence to grow on the sugary and gummy 

 substances in imperfectly washed rubber and ultimately on the 

 decomposing proteid or albuminous material previously referred to. 

 It can to a great extent be kept in check by well washing and squeezing 

 the freshly-coagulated rubber, rapid drying without exposure to 

 high temperatures, and the use of formalin in the latex and on the pre- 

 pared rubber. Mr. Kelway Bamber recommended that the biscuits 

 be wiped with a solution of formalin, diluted to make a 2 per cent, 

 solution, and not be allowed to touch one another earlier than 

 necessary. 



§ E. E. Green. Entomological Notes, Tropical Agriculturist, October, 

 1905. 



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