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develops at first entozooically but later ectozooically, and as a rule 

 there is but one parasite to each cocoon. If there be two, the insects 

 are of small size. They were fairly numerous at the end of the first 

 harvest of 1913 and probably have some practical importance. 

 Species Y. is a very small black Chalcid ; several develop in one cocoon, 

 and as they reproduce parthenogenetically, there is hope of being 

 able to raise them in quantity. Phanurus {Ceraphron) heneficiens 

 and the native TricJiogrmnma australicum minutum and Trichogramma- 

 toidea nana were tried, but Phanurus is too large and the Tridwgramma 

 refused to have anything to do with the cacao moth cocoons. 

 Observations on a large mass of living material has shown that a 

 small percentage of parasites undergo an aestivation period of about a 

 month's duration. The pupal stage apparently begins but does not 

 continue, and the larva acquires a thick parchment-like integument 

 and so remains until the rains, when true pupation takes place ; no 

 difference was, however, observed between the resulting imagines and 

 those produced in the ordinary way. Species B. is specially prone to 

 this peculiarity. Species C. acts also as a hyperparasite on the 

 caterpillars of the Limacodid, Setora nitens, which are often killed 

 by a Braconid larva. The introduction of parasites of the cacao moth 

 to Assinan is reported to have yielded most excellent results. 

 A campaign against wild food-plants must be undertaken and this is 

 the more necessaiy as a caterpillar has been found on a leguminous 

 tree, Saraca declinata, which so closely resembles that of the cacao 

 moth as to lead to the suspicion that the aboriginal insect and its food- 

 plants have been discovered. The tree is largely planted for ornament 

 in gardens and parks, but is also to be found wild ; numbers of other 

 trees growing near cacao plantations showed no sign of cacao moth 

 infestation. The perfect insects when bred out were not absolutely 

 identical with the cacao moth, and may be a new species of Acrocercops. 



Helopeltis did more damage than usual in the year under review, 

 1913-14, and attention is drawn to the great quantities of its food- 

 plants grown for ornament, while the wild food-plants are also on the 

 increase. The Zeuzera borer is also stated to have done much damage. 

 Xylebonis coffeae has been found to be attacked by a Chalcid, probably 

 of the genus Apostrectus, and such large numbers have been bred out 

 from cofEee branches attacked by the borer that it is difficult to 

 understand why the parasite is not more effective. Investigation is 

 not easy because the Chalcid is a night-flyer and daylight studies on 

 the spot are almost useless. This habit, and the want of a coffee garden 

 close to the station, made the laboratory work difficult. Infestation 

 tests on a small scale in captivity succeeded and showed that even the 

 unfertilised females can reproduce, though only males result. The 

 method of infestation could not be observed, as it probably takes place 

 at night, and during the day the parasite took no notice whatever of 

 the borers. 



A pest of kapok, apparently identical with Arbela tetraonis, Moore, 

 from India, and new to Java, is recorded. It also attacks other trees, 

 especially Leguminosae, and has been found on cacao. 



A caterpillar borer of the kapok pods, which is occasionally very 

 numerous, is under observation, and a number of pupae are being reared 

 in order to determine the species. Coca is suffering from the attack of 

 Prodenia litura {littoralis), of some spepies of Boarmia, and of a brown 



