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altitudes under 4,300 feet, H. antonii injures both tea and cinchona, 

 while higher up it is represented by a larger, darker-coloured variety 

 which usually prefers cinchona and which is probably the species 

 formerly described as H. bradyi. On some estates this variety occurs 

 on tea at a lower level, about 4,000 feet. Above 4,300 feet, HelopeUis 

 has not done serious injury up to now, but below that elevation 

 cinchona is a dangerous neighbour for tea. Preliminary experiments 

 were made with many green-manure plants and weeds. Various 

 species of Tephrosia, especially T. vogelii, which have already estab- 

 lished themselves in some estates, are dangerous. Bixa and Gardenia 

 are also dangerous as being possible food-plants. Clean weeding, 

 immediately after pruning, and the simultaneous pruning of green- 

 manure plants are the measures advised. In Java infestation is most 

 serious during the west monsoon ; it decreases and disappears during 

 a prolonged drought. The natural enemies of Helopeltis include 

 Mantids, Reduviid bugs and spiders. Spiders were successfully 

 imported from Europe and hundreds of thousands were released, but 

 up to now none have been recovered. A specimen of Helopeltis has 

 been found infested by Metarrhizium anisopliae, but this fungus cannot 

 be expected to be an important enemy. The results of research 

 regarding the relation between Helopeltis and cultural operations in 

 tea-growing were not conclusive. An instance of success with forced 

 plucking was reported from Soekamadjoe, but this may not apply 

 everywhere. In investigating the occasional spontaneous disappear- 

 ance of Helopeltis no proof was obtained of the tea plants becoming 

 immune, though the strongest tend to survive. There is no ground 

 for believing that individual plants are not susceptible to the punctures 

 of Helopeltis or that the bugs avoid certain tea plants. Lack of food 

 due to intense and uniform attack, the removal of the insects by wind, 

 prolonged* drought and sunny weather, may combine to bring about 

 the spontaneous disappearance of the insects. High table-pruning 

 during and after an outbreak seemed to give better results than close 

 pruning. Prunings should be destroyed, at any rate during the west 

 monsoon, and the stems bearing eggs should be removed. On one 

 estate where capture was practised for four months at a cost of about 

 3s. ^d. per acre per month, this expense was held to be fully justified 

 by a comparison wdth another property where this method was not 

 adopted. Experiments in spraying with a 2 per cent, soap solution, 

 a control new to Java, gave good results if the applications were made 

 immediately after pruning and areas of 70 acres or more were pruned 

 within one month. On plants with dense foliage the result was not 

 so favourable. On 280 acres searched and sprayed the area of severe 

 infestation only amounted to 3-5 per cent, after seven months. The 

 cost of searching and spraying was about 2s. per acre per month. 



d'HERCULAis (J. K,). La Guerre centre les Sauterelles. Les dernieres 

 Invasions dans I'Afrique du Nord. Moyens de Defense et de 

 Destruction. [The War against Locusts. The last Invasions 

 into Northern Africa. Control Measures.] — Bull. Soc. Nat. d'Accli- 

 matation, Paris, xhii, nos. 11 & 12. November & December 1916, 

 pp. 460-467 & pp. 508-578. 

 In this article the author reviews the work done in controlling 



Dociostuurus {Stauronotus) maroccanus and Schistocerca peregrina in 



