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the chlorophyll of the parenchyma. The female of P. cumingi in 

 the Phihppines pierces this hole before laying the egg. The 

 larva continues to extract chlorophyll from the leaf within which it 

 hves and develops, causing a drying up and blistering which are 

 the characteristic signs of its presence. There are at least two larval 

 moults ; on examination of imagines that had died without being 

 able to effect their exit, shed skins were found indicating three larval 

 moults, and this may be the correct nmnber. Owing to the larva 

 living within the leaf the length of the various larval stages has not been 

 ascertained, but the total larval hfe is probably from 35 to 37 days. 

 Pupation occurs within the leaf and lasts from 8 to 10 days, the imago 

 emerging by piercing a hole in the upper epidermis. The length 

 of the various stages of P. opacicoUis in the New Hebrides and of 

 P. cumingi in the Phihppines are compared. In the Phihppines the 

 adult remains from two to four days within the leaf before emerging, 

 and the same probably occurs in the New Hebrides. 



The damage caused by the adults is more restricted and would 

 seem less serious than that by the larvae, but the continual laceration 

 caused by the repeated nibbhng finally results in ahnost equal damage. 

 The yoimg leaves at the head of the tree are generally the first attacked, 

 palms of less than three years old being seldom injured. 



A Hymenopterous parasite of the eggs of P. opacicoUis was collected 

 by the author and is described as Oligosita utilis, sp. n. The method 

 of parasitising the eggs, which occurs after the construction of the 

 capsule, is described, the ovipositor of the parasite being sufficiently 

 long to penetrate the eggs within. Oviposition is, however, a difficult 

 matter, requiring from six to fifteen minutes, or even longer. During 

 a three hours' observation the parasite was seen to parasitise at least 

 16 eggs. It is evident that the parasite is common, and should be 

 of great value to planters. At the time of these observations the 

 number of parasitised eggs of P. opacicoUis was about 40 per cent., 

 but this figure varies considerably in different locahties. It is suggested 

 that efforts should be made to equahse the nrnnbers of the parasite 

 by transporting it from locahties where it is abundant to others where 

 the pest is far in excess of the parasite. Another Hymenopteron, 

 Closterocerus splendens, sp. n., is described as parasitic upon the larvae 

 of P. opacicoUis. This species is alhed to C. insignis, Waterst., from 

 Ceylon. The method of parasitisation is described, the eggs of the 

 parasite being inserted into its victim through the epidermis of the 

 leaf that shelters it. Only the third-stage larvae are attacked, the 

 individuals of the previous stages probably being too small to provide 

 nourishment for the development of the parasite. Whether the pupae 

 also are attacked, as is the case with thePhihppine species, is not known. 

 C. splendens appears to be disseminated throughout the Archipelago, 

 but less abundantly than 0. utilis, and is very easy to breed. The 

 larva when fully developed leaves its host and pupates in about four 

 days, the adult emerging about 15 days later. Other Hymenopterous 

 parasites of Promecotheca exist, but cannot yet be identified, though 

 two have been recognised as belonging to the Entedon group, while 

 another is probably a Proctotrupid. 



Predaceous enemies of P. opacicoUis include ants, which destroy 

 many of the larvae and are always abundant on coconut palms, 

 and certain birds. It is suggested that the latter should be encouraged 



(601) b2 



