415 



but the so-called Java-China tea is the most liable. Some planters 

 have thought it possible to use it to attract HelojjeUis, but it is dangerous 

 to grow it near Assam tea. 



Helopeltis cannot be combated on cinchona unless the plantations 

 are very young, and it can multiply on this plant to an unlimited 

 extent. It is therefore advisable to decrease the danger as much as 

 possible by doing cultural work (cutting and hoeing) in cinchona 

 plantations before adjacent tea-gardens are in the condition most 

 susceptible to Helopeltis attack. 



An elaborate investigation was made on the food-plants of H. antonii, 

 on the weeds occurring in tea-gardens and on the leguminous plants 

 used for green manuring. It was found that H. antonii could not live 

 on Leucaena glauca and Clitoria cajanifolia. Tephrosia vogelii is 

 definitely dangerous, and caution is advised in respect of T. Candida, 

 T. hookeriana var. amoena, Alhizzia moluccana and Erythrina indica 

 (dadap). When infestation is severe not only the tea, but also the 

 green manure plants should be pruned. Dangerous food-plants are 

 Bixa oreUana- and Gardenia florida, often used for hedges. Weeds 

 which were attacked under laboratory conditions, and on which 

 Helopeltis lived for a considerable time, included Richardsonia 

 brasiliensis, Melastoma nudabarthricirm, Erigeron linifoliiim, Bidens 

 pilosa, Dichrocephala latifolia, and Erechtitis valerianaefolia. These 

 weeds were also attacked in the tea gardens, chiefly when the tea was 

 pruned low. Clean weeding therefore seems advisable very soon after 

 (sometimes before) pruning, in order to prevent the insects from 

 remaining on the weeds until the tea shrubs bud again. The awi tali 

 bamboo {Gigantochloa apus) is suspect, for the insects remained alive 

 on it for 10 days, while casso {Sacckarum spontaneum), alang alang 

 {Imperata arundinacea) and Lantana camara seem harmless. It was 

 not possible to find a bait-plant more attractive than tea. On one 

 plantation VUlehrunnea ruhescens had been planted in places as an 

 attraction for Helopeltis, on account of spots being noticed on its leaves. 

 These turned out, however, to be due to Pachypeltis vittiscutus, Bergr., 

 a fact which points to caution in assuming that injury similar to that 

 done by Helopeltis is necessarily due to Helopeltis. A list is given of 

 44 food-plants of Helopeltis mentioned in literature. The author 

 states that H. antonii from tea lived up to 21 days on cacao, so that 

 cacao growing near to tea may be endangered. 



H. theivom, Waterh., also oviposits in the young stems chiefly, but 

 it has a greater liking for the leaf-nerve than H. antonii. Its eggs 

 develop in 7-8 days on an average. Its newly-hatched larva has the 

 same appearance as that of H. antonii, but after the first moult 

 difterences become distinctly visible. The longest time a female was 

 observed to- live was 42 days ; the longest oviposition period was 32 

 days ; the maximum number of eggs was 172. The injury done by 

 H. theivora camiot be distinguished from that by H. antonii. The 

 green manure plants on which H. theivora can five while tea is being 

 pruned are Alhizzia moluccana, Erythrina indica, Tephrosia Candida, 

 T. vogelii, and T. hookeriana. On Leucaena glauca and Clitoria it only 

 survives for a short time. In west Java it lives and breeds on cacao. 

 Experiments \^ith weeds gave practically the same results as in the 

 case of H. antonii. 



