364 



grass wLicli must be removed, bm-nt and replaced at regular intervals 

 during the flight period, thus destroying the eggs. Collection of the 

 larvae is also necessary. A measure recommended against the larvae 

 of both -pests is watering the beds, 3-4 months before the seed is 

 planted, wth a weak solution of carbolineum, 1 part to 250 of water. 

 If this insecticide is used when the beds have already been sown, a 

 solution of 1 in 500 must be used at the rate of 3|-7 oz. per 11 square 

 feet. 



WiERENGA (0. M.). Waarschuwing tegen de Anggrang (Roode Mier). 

 [A Warning against the Red Ant, Oecophylla smaragdinu.] — 

 Meded. Proefstation Malang, Soerabaya, no. 13 [1916], pp. 15-16. 

 [Received 23rd June 1919.] 



As it is very difficult to work in plantations that are severely infested 

 by Oecophylla smaragdina, the eradication of this ant is very necessary. 

 Of all the methods tried the only one of real value is the destruction 

 of the nests, which must be collected, and the ants and their eggs 

 thrown into hot water. As attempts will be made to form new nests 

 these must be looked for and burnt out by means of a gasolene torch, 

 which should be fastened to a 6-foot stick in order to prevent the 

 operator from being bitten. For some time after the nests have been 

 dealt with the ground will swarm with ants and the only means of 

 protecting the workers consists in rubbing the legs with rice powder. 

 As the powder is applied wet the surface becomes so smooth that the 

 ants are unable to climb up it. 



ScHENK (P. J.). In en op den Bodem levende Plantenvijanden. II. 



[Plant Enemies living in or on the Ground.] — Tijdschr. Planten- 

 ziekten, Wageningen, xxv, no. 3, May 1919, pp. 101-125, 8 figs. 



The first portion of this paper on plant pests in Holland has already 

 been noticed [see this Revieiv, Ser. A, vi, p. 498]. Some species of 

 Elaterid beetles, including Lacon murinus and Agriotes lineatus, are 

 injurious to vegetables and fruits ; bait- traps or poison-baits are 

 advocated against them. Tipulid larvae caused extremely severe and 

 wide-spread damage to vegetable and fruit crops planted on grassland 

 during the War. In one instance 300 strawberry plants only remained 

 out of 25,000. Against Euxoa (Agrotis) segetum and other cutworms, 

 benzine is recommended in preference to carbon bisuljjhide. Small 

 holes are made in the ground and a thimbleful of benzine is poured 

 into each. The holes must be immediately closed. The adults ma_y be 

 captured in light-traps. In Holland Gryllotalpa gryllotalpa occurs chiefly 

 in peat soil, but this mole-cricket may be found in sandy and clay soils 

 provided their character is not too pronounced. Trap-trenches are used 

 against this pest, the life-history of which is still obscure on many points. 

 About 300-400 individuals were securely confined together and the 

 number gradually decreased until the sole survivor was ultimately 

 found dead of starvation. This proves G. gryllotalpa to be cannibalistic 

 when other food is not available. Blaniulus guttulatus appears 

 to be the most harmful millipede. Bait-traps are recommended 

 against it. 



