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The first section is systematic, the four species, Hehjjeltis anionii, 

 Sign., H. antonii Yar. bradyi, Waterh., H. theivora, Waterh., H. cuneatus, 

 Dist., and H. cinchonae, Mann, being described, and their distribution 

 in Java and Sumatra recorded. A simple table is also given to enable 

 planters to distinguish Helopeltis from other insects which the native 

 collectors may bring in. 



The second section deals mth the biology of the different species in 

 detail. Altitude influences the developing stadia of H. antonii. The 

 egg-stage lasts 7-8 days at 800 feet, 8-11 days at 3,600 feet and up to 

 14 days (according to temperature) at 4,200 feet. The larval stage 

 lasts 10-14 days at 800 feet, and 15-24 days at 3,600 feet. The females 

 lived up to 50 days. A laboratory count showed that of 929 eggs, 610 

 were laid in the young green stems, 183 in the swollen base portion of 

 the leaf-stem, 91 in the leaf-stem, and the remainder elsewhere. 

 Neither laboratory nor field examinations have yet revealed eggs in the 

 woody parts. In the laboratory larvae developed from 87 to 95 per 

 cent, of the eggs from three females. The development of the larvae 

 does not appear to be influenced by shade ( = lower temperature). 

 On most estates where catching is practised, the work is usually done 

 between 6-8 a.m. and again between 4-6 p.m., but a considerable 

 number of Helopeltis may also be taken between 8 a.m. and 4 p.m. 

 "VMien the heat of the sun increases the younger larvae often remain 

 on the injured and slightly curled leaves, being sometimes found there 

 at noon, but the older larvae seek shelter on the shaded twigs. These 

 older larvae are very shy and quickly move downwards or let them- 

 selves fall when disturbed. The larvae of H. antonii do not seem to be 

 so active as those of H. theivora. The planters appear to be right in 

 thinlving that larvae predominate in the morning catches and adults 

 in the afternoon ones. The heat of the sun-warmed ground affects 

 the larvae (this may be useful when pruning), and only when compelled 

 do they migrate from one tea shrub to another. Once on the move 

 their progress is rapid and neither irregular ground nor a vertical- 

 sided tren€h can impede it. The probable cause of the damage to tea 

 leaf is supposed to be a poisonous secretion in the puncture. Like the 

 larvae, the adults prefer the under-side of the leaves and usually feed 

 in the morning and afternoon. Unless disturbed they migrate but 

 little. They cannot face even a moderate wind, and there is no doubt 

 that wand-carriage is a factor in their spread. Windy situations are 

 avoided by them. The infestation was usually more serious in valleys, 

 on hill-sides, or at the edge of jungle or other wind barriers. Protective 

 tree-belts are therefore useless and may even be dangerous at times, 

 as the insects are liable to accumulate there. In one case success was 

 obtained by cutting down such a barrier, allowing free entrance to the 

 wind. As a result of enquiries sent to 57 estates as to the season when 

 most damage was done, 44 replies were received indicating the west 

 monsoon (rainy season), 5 the east monsoon (dry season), and 8, both. 

 It is therefore important that control should be practised also in the 

 dry season. In the author's opinion Helopeltis aestivates on tea. 

 This circumstance greatly favours control. Of the plantations 

 infested about 70 per cent, were at an altitude of 1,000-4,000 feet ; 

 4,300 feet appears to be the extreme limit. The tea shrubs afford the 

 insects all the shade that they require, so that the presence or absence 

 of shade- trees is immaterial. All varieties of tea in Java were attacked, 



