8 May, 1907.] Fruit Flies. 307 



When fruit is easilv punctured the fly distributes its eggs tliough many, 

 but occasionally eight, and even the whole batch are placed in one fruit. 

 It is not usual to find eggs laid in fruit before it is two-thirds grown, as 

 the female seems to defer operating till a pleasant odour from the fruit 

 is perceptible. 



Regarding the periods of development at which the Fruit is attacked, 

 Mr. Tryon, together with Mr. Searle, furnished some reliable information. 

 " The eggs take three davs to hatch when under observation, but in the open 

 air this will be hastened or retarded by climatic conditions. Occasionally 

 the young grubs are killed because the growing fruit presses upon them 

 and in other cases the young are unable to break down the tough woodv 

 tissue of immature fruit. In mellow saccharine fruits all the eggs hatch 

 out, and the grubs mature unless the tunnel becomes closed and excludes 

 the air. In pip fruit and slipstone peaches the gruljs can live near the 

 centre, but in close stoned fruit they must work near the surface. 



" The life of the grubs in the fruit is from two to fi\e weeks, occasion- 

 ally less than two weeks. It invariably happens that when the grub has 

 done feeding, it leaves the fruit, which has usually fallen to the ground. 

 After leaving the fruit the grub usuallv tries to hide beneath the soil, some- 

 times going as deep as four inches, and then within twenty-four hours 

 changes into a chrvsalis. 



" In summer a period of from se\"en to fourieen da\ s elapses before the 

 fly is out of the chrysalis, but in winter the lethargic condition continues 

 much longer. There are several broods during the vear, and from August 

 to April (in Queensland and New South Wales) reproduction is virtually 

 continuoas, as females preponderate and as each lays twelve eggs, pro- 

 digious multiplication is the result. Occasionally the flv passes the winter 

 as a perfect insect. The ability to breed throughout the year is due to the 

 succession of fruits from loquats to oranges in winter. " ' 



^lany larvae of this flv reach iNIelbourne in bananas, oranges, cucumbers, 

 &c., and haA-e been reared bv me. The habits are almost similar to those 

 of the Mediterranean fruit-fly, but the insects sometimes take longer to 

 hatch. The majority of larvae placed in breeding jars on 20th August, 

 pupated on 28th August, and emerged on 6th XovemL)er ; others took only 

 six weeks to hatch, and lived sixteen days without food. Mr. E. J. 

 O'Connor, of Ivanhoe, kept this flv alive for nine weeks b\ feeding it with 

 oranges and water. 



Queensland Fruit Fly. 



Variety cucuinis. French. 



I have given the alxDve name provisionally to the fruit-flv reared from 

 cucumbers sent from Boiwen (Queensland). It is closely allied to the 

 Queensland fly ; but the well defined yellow bands on the abdomen are 

 w anting ; the whole colour of the fly is much lighter in^ appearance, and the 

 pupa-cases are a little larger. The larvae are of a deeper colour than those 

 of the ordinary Queensland fly, and no less than fifty eight larvae were taken 

 from one cucumber. The maggots were received from Queensland on 22nd 

 October, and pupated on 25th October. The perfect insects which 

 emerged on the 2TSt November, lived only twenty-four days, whereas the 

 Queensland flies will live for weeks. The larvae of this fly also have the 

 peculiar habit of curling up and jumping, beating badly all previous records 

 that I have observed of the jumping propensities of fruit-flv larvae. 



