28 MONTHLY NOTES ON GEUBS AND OTHER CANE PESTS. 



haps au erroneous conclusion — that this substance is attractive to the 

 beetles. In each case the cane had grown rather rank before the cyclone, 

 and probably went down more easily for that reason. I have no doubt that 

 grubs were also in the untreated parts of the fields, though for lack of 

 time I was unable to demonstrate this. 



From the pits that were dug I got both grey-backs and frenchi, the 

 latter species much in the minority, since it usually favours wild grass- 

 land. 



Parasites of the Cane Borer Beetle. 



One of the most important observations of my trip was the discovery 

 that the cane borer beetle parasites {Ceromasia splienopliori) are well 

 established at Mossman. It will be remembered that Mr. F. Muir, the 

 entomologist of the Hawaiian sugar-planters, brought these flies to the 

 district in 1910, where he bred them on borers in large cages, prepara- 

 tory to the long trip to Hawaii. I do not recall whether any of the 

 flies were liberated deliberately at Mossman;* but in the breeding of 

 parasites specimens escape from time to time as the doors of the cages 

 are opened. At any rate, the flies are now thoroughly established there, 

 and are doing most excellent work. I was unable to find any of the 

 borers that had escaped the search of these persistent parasites, except 

 where the canes Avere so buried up in trash that the flies could not get 

 at them. 



This find is most fortunate for the canegrowing sections of the 

 North, for we now know that the flies can live and thrive in Queensland, 

 and that they are able to hold the borer beetles in cheek. The unsuccessful 

 attempt of the Colonial Sugar Refining Company to establish these para- 

 sites at Goondi in 1914 led us, naturally, t6 conclude that they could 

 not live here, presumably because they were preyed upon by many 

 enemies, as we found to be the case in Fiji. 



The borer beetle is becoming increasingly abundant in the cane- 

 growing sections of North Queensland, due largely to the lack of care in 

 the selection of clean seed. In one instance I found a farmer deliber- 

 ately using this cane for seed, because it was so badly attacked by the 

 borers that it was worthless for milling. It is easy to surmise the result 

 of such a practice. 



With the parasites well established in a near-by district it will be 

 a simple matter to introduce them into other centres of infestation, 

 using care only to transfer them at a favourable season. 



Innisfail District. 



It M-as here, in the section kaoAvn as Daraji, that the C.S.B. tried 



to establish the parasites of the cane-borer beetle, so I took the first 



opportunity to visit the farm where the flies were liberated in 1914. 



The borers were rather difficult to find — a fact which might indicate 



* I have since leanicfl tliat these flies became established in the field in 1010. — .LF.I. 



