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H. theivora, are described ; the former occurs at higher altitudes than 

 the latter, both species being found on tea, cacao and cinchona. 

 Oviposition usually begins soon after fertilisation, but may be greatly 

 delayed if the conditions are unfavourable. The eggs are laid in 

 small numbers over a long period, at the most four or five daily. The 

 average life of the female is about a month, but it is probable that 

 many individuals live as long as two or three months. The external 

 factors which influence the fertility of the insect are uncertain. The 

 eggs are laid in the soft parts of the plant, especially in the pods. 

 In the shoots and the stems of the fruit while they are yet young and 

 tender, they are so placed that the whole of the egg lies within \he 

 tissues of the plant, not more than four being laid in the same spot. 

 In the case of cacao, the fine down which covers the young plant 

 hides the projecting threads on the eggs, but a black spot develops, 

 which enables the point of oviposition to be detected. The egg-stage 

 lasts about six days. The larvae are active and, in the presence of 

 suitable food, become full grown in about 10 days, moulting five times 

 in this period. If the food-plant becomes too dry, the larvae die 

 rapidly of hunger. The mechanical injury due to the numerous 

 punctures is less serious than the loss of sap which results, and 

 the poisonous effect on the plant of the salivary secretions. A list of 

 trees and plants attacked hy Helopeltis is given, the most important 

 being cinchona, tea, cacao, kapok, black pepper, cinnamon, camphor 

 and rubber {Ficvs elastica). Numerous cultivated garden plants as 

 well as wild plants, including various species of Solanum, also serve as 

 hosts. Pods which have been badly attacked by Helopeltis are bored 

 by Aegeriid larvae and other insects, which are, however, only of 

 secondary importance. The attacks of this pest are especially serious, as 

 the whole plantation usually suffers, and not only is the crop of fruit 

 lost, but the health of the whole tree is seriously affected. No insect is 

 so iiTegular and uncertain in its appearance as Helopeltis. It does not 

 occur equally throughout the year, and in normal years there is a more 

 or less definite maximum and minimum, the latter occurring during 

 the second half of the east monsoon, the former in March and April. 

 Exceptions to these rules constantly occur however, and unfortunately 

 the experience of the past two or three years disposes of the theory that 

 this insect cannot withstand long drought. Certain locahties are 

 regarded by the planters as foci from which the pest spreads ; these 

 are usually undisturbed places not yet brought under cultivation, 

 well protected from the wind and in which throughout the year a 

 certain degree of moisture is maintained. In the plantations them- 

 selves much depends on the age of the trees ; cinchona only suffers 

 seriously when the plants are young, but once attacked, the pest 

 continues its ravages on the young leaves. In the case of cacao, both 

 old and young plantations suffer equally. The elevation of the 

 plantation is an important factor, the attacks being generally more 

 serious on low-lying than on elevated ground. In cinchona plantations 

 Helopeltis causes the least damage when these are enclosed and thickly 

 planted, the attack being then generally confined to the borders. 

 Cacao suffers most where there is the least shade, and the planters 

 regard the Helopeltis question as largely one of shade, though well 

 shaded plantations are by no means free from this pest. Tephrosia 

 is the only shade plant attacked by Helopeltis, but it has only been a 

 (C322) aS 



