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Dutch, vernacular, and scientific names of the pests or diseases concerned 

 and the nature and appearance of the injurj'. The second describes 

 the remedies advocated. 



The insect pests inchide Coptotcrmes gestroi, boring the roots and 

 stems ; a beetle. Platypus sp., which mines the stem, starting from a 

 point where the bark is absent or injured ; and mites, which attack 

 the young leaves, especially in seed-beds. 



C. gestroi may be destroyed by fumigation, a mixture of three parts 

 arsenic and one part sulphur being burned in one of the commercial 

 apparatuses that are now obtainable. In localities where this termite 

 occurs, all tree stumps and dead timber must be removed and burned. 

 Infestation by Platypus may be prevented by painting all wounds 

 with a thick coat of tar mixed with fine sand, with a mixture of one 

 part solignum and one part petroleum, or with one part of paraffin and 

 naphthaline. The surface may also be painted with linseed oil, 

 petroleum, etc., prior to the application of a coat of tar ; a coat of 

 tar alone may sometimes prove inadequate to prevent the beetle 

 from entering. Beetles already in the wood may be killed by binding 

 the wounds with sacking steeped in petroleum. Mites need no special 

 measures ; they usually disappear after heavj^ rain. 



Cohen Stuart (C. P.). Hooge Produktie door zorgvuldigen Pluk en 

 Insektenbestrijding. [High Production through careful Plucking 

 and Insect Control.] — De Thee, Buitenzorg, ii, no. 1, March 1921, 

 pp. 5-7. 



A communication from the' manager of a 115-acre tea estate 

 emphasises tjie importance of careful plucking and sufficient insect 

 pest control as factors in remunerative production. A table covering 

 the years 1914-20 shows for each year the crop yields, the number 

 of Helopeltis, caterpillars and cocoons collected, and the costs per acre 

 and per lb. of dried leaf. The average cost of control was about 

 8s. Ad. per acre (at par) or Is. 3|f/. per cwt. of dried leaf. The estate 

 maintenance costs varied from about 34s. per acre in 1914 to 65s. 

 in 1920. 



Keuchenius (A.). Proeven over de Sehade door de Theezaadwants 



veroorzaakt. [Tests on the Injury caused by the Tea Seed Bug.] — 

 De Thee, Buitenzorg, ii, no. 1, March 1921, pp. 9-12, 2 plates. 



In view of the reported damage to tea seed by a Pentatomid bug, 

 Poecilocoris hardwicki [R.A.E., A, viii, 453], experiments were made 

 to ascertain if the piercing of the berries seriously injures the seed and 

 causes the " white spots " on the seed-lobes thought by some to be due 

 to fungi. 



Four cages were arranged on different twigs of the same plant and in 

 each of two of them about 100 bugs were placed. After 2| months 

 it was found that the berries in the control cages were quite normal, 

 and a test of the resultant seeds showed that only 33 per cent, floated, 

 and that there was a germinating power of 74 per cent. In the cage? 

 where the bugs were present, about 40 per cent, of the young berries 

 failed to develop and withered on the twigs. On opening the 

 remaining — apparently normal — berries, all the seeds floated when 

 tested. Externally these seeds were more or less shrivelled, and in 

 29 per cent, of them the seed-lobes and germs were shrivelled. The 



(3393) 2 c 



