December, '19] illingworth: sugar cane borer parasite 457 



dropped a bit of paper over them. I tried this in the trays when the 

 larvae were feeding, and found that it worked equally well. 



The cocoons were then left in the cells to emerge; attention being 

 given to keep the soil from drying out. There was not much difficulty 

 experienced in this matter, since I kept the trays stacked, one upon 

 another. 



A small glass tube was inserted into the end of each tray, and this 

 being the only entrance of light, the wasps naturally came into the 

 , tubes as fast as they emerged, and were easily removed. 



It will be interesting to record here a further instance of parthen- 

 ogenesis among parasitic hymenoptera. We found that wasps reared 

 in the laboratory, with no opportunity for mating, began egg-laying at 

 once when grubs were provided, and these eggs hatched producing 

 larvae of both sexes, though there was a preponderance of males, as one 

 would naturally expect. However, these unmated females produced 

 fewer eggs than normal, and the offspring emerged poorly. 



THE SUGAR CANE BEETLE BORER PARASITE fCEROMASIA 

 SPHENOPHORI) IN QUEENSLAND 



By J. F. Illingworth, Gordonvale, near Cairns, North Queensland 



This valuable Tachinid fly, introduced from New Guinea, in 1910, 

 by Frederick Muir of the Hawaiian Planters' Association, has become 

 thoroughly established in the Mossman district, and has done inesti- 

 mable good. 



It may be recalled that the beetle borer (Rhabdocnemif. ohscura) 

 came into North Queensland, accidentally, about 1893, with importa- 

 tions of seedcane from New Guinea. Tliis serious cane pest, which is 

 second only in importance to the white grubs, has become well estab- 

 lished in most of the northern districts, and already extends as far 

 south as Mackay. Furthermore it is rapidly spreading to new terri- 

 tory through the indiscriminate exchange of seed between the different 

 sugar centers. 



The importance of this pest has long been recognized, especially Ijy 

 the Colonial Sugar Hefining Company, who own a number of mills in 

 the infested districts; and they made a serious, though unsuccessful 

 attempt, in 1914, to introduce these Tachinid parasites from Fiji, 

 where I had bred them and established colonies during 1913. They 

 bred the flies in large field-cages at Goondi, on the Johnstone River; 

 and though good-sized colonies were liberated, the parasites failed to 

 become established. The season of 1914 was exceptionally wet; and as 



