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in their activity, especially in East Java. Four species and their 

 parasites are dealt "with in this report : — Diatraea striatalis, Sn. (the 

 striped stalk borer), Chilo infuscatelhis, Sn., (the yellow tip borer), 

 Scirpophaga intacta, Sn. (the white tip borer), and Olethrentes {Grapho- 

 litha) schistaceana Sn., (the gray borer). The most important egg 

 parasite of D. striatalis is Phanurus heneficiens, Zehnt. Eggs infected 

 by Phanurus, are easily recognisable in the cane-fields by their brown 

 colour, and if these are collected in glass tubes or glass-topped boxes, 

 there is no difficulty in breeding them out. The adults are attracted 

 by light, the females much more so than the males, so that by the 

 simple process of placing the infected eggs in a test-tube closed at one 

 end mth a plug of cotton wool, and exposing the other end to the hght, 

 the sexes can be very readily separated on emergence. If the females 

 be provided with eggs of Diatraea on a leaf in a glass tube, these are 

 at once attacked, but it was observed that only those were parasitised 

 which were not more than 3-4 days old. It is not necessary that the 

 females should be fertilised for oviposition to take place ; the operation 

 lasts about one minute for each egg attacked, and the parasite 

 apparently confines its attack to one egg-cluster. The hfe of the adult 

 parasite is very short ; in a dry atmosphere, when denied all access 

 to liquid, barely one or two days. If Muir's method be used, in which 

 a fresh moist leaf is introduced daily (the author used the leaves of 

 Portulaca olemcea [purslane] with success) so as to obtain a really 

 moist atmosphere, the life is greatly prolonged. The proportion of 

 the sexes is about equal. When a pair had been left together with a 

 supply of Diatraea eggs, the emerging brood of parasites consisted 

 almost entirely of females. Even unfertilised females generally give 

 rise to a majority of females, though occasionally males only were 

 produced. Parasitised eggs, 14 lots, collected in the open yielded 

 750 females and 70 males ; in four cases, no males ; and it is argued 

 from these figures, that parthenogensis is common in nature. Other 

 egg-parasites of D. striatalis are, the Chalcids, Trichogramma {Chaeto- 

 sticlia) nanum, Zehnt., T. australicum, Gir., and T. mimdum, Riley 

 {— T. pretiosa, Riley). T. australicum was easily bred in the same 

 way as Phanurus ; emergence invariably took place by day, but instead 

 of only one parasite per egg infected, as in the case of Phanurus, 

 usually two or three and, in a few cases, as many as six were obtained. 

 The adults seek the light, but not so markedly as Phanurus ; the 

 parasites emerge in 9-10 days. Parthenogenetic reproduction in the 

 case of T. australicum, in seven separate observations, yielded ex- 

 clusively males, and there is some reason for supposing that this occurs 

 in nature. The hfe-history of T.mimttum and T. nan>im is apparently 

 very similar to that of T. australicum, but it was not possible to obtain 

 them in sufficient numbers for study. Bodkin's accomit for British 

 Guiana is considered to represent fairly conditions in Java [see this 

 Revieiv, Ser. A, i, p. 319.] A Braconid and a Tachinid, both undes- 

 cribed, parasitise the larvae of Diatraea ; they are rarely, if ever, found 

 in the burrows and it seems probable that they only attack the larvae 

 when outside. Two species of ant, a large red, and a small black one, 

 attack the pupae and the latter carries off the eggs to their nests : a small 

 Carabid also eats the larvae. The folloNnng list of known parasites 

 of Diatraea is given : — Egg-parasites : Trichogramma mimdum, 

 Riley (Br. Guiana, Porto Rico, Louisiana), Telenomus sp. (Br. 



