16 THE MEDITEERANEAN FRUIT- FLY. 



fruit-flies only under certain conditions. A small parasitic wasp 

 {Oiylellus trimaculatus Spin.) was reared from a related fruit-flj', 

 Anastreflia fratercida^ and maggots infesting small fruits showed a 

 higher percentage of parasitism. Another small wasp was observed 

 crawling over peaches and in one instance apparently ovipositing in 

 the fruit and was suspected of being parasitic on fruit-flies. At- 

 tempts were proposed to determine if the Opiellus parasite would 

 also attack the Mediterranean fruit-fly, though apparently without 

 much hope, as Mr. Lounsbury concludes : 



Whilst there still appear these possibilities that fruit fly parasites exist iu 

 Brazil that might prove of some value against South African fruit flies, I no 

 longer have any hope whatever that these parasites may be capable of holding 

 our fruit flies in such close subjection that artificial measures to save orchard 

 fruits will become materially less necessary than they are at present. 



Mr. W. W. Froggatt, under the auspices of the Governments of 

 New South Wales, Victoria, South Australia, and Queensland, spent 

 a year (July, 1907, to July. 1908) in an investigation of entomolog- 

 ical questions in foreign countries, and during his trip around the 

 world particular attention was paid by him to the subject of insect 

 control by parasitic and predator^^ insects, especially with reference 

 to enemies of fruit flies (Eeport on Parasitic and Injurious Insects, 

 Department of Agriculture, New South Wales, 1909). No reference 

 is made in this report to the discovery of natural enemies of fruit- 

 flies, and that no \\o\)Q is felt in such work is shown by the following 

 statement (p. G8) : 



I consider, as do nearly all leading entomologists who ha^-e given the matter 

 of fruit flies any attention, that it is very improbable that any internal para- 

 site will ever make any impression on this pest in the case of commercial 

 fruit, such as oranges, peaches, etc. In all cases where parasites have been 

 bred it has been from small, wild, or hard-fleshed fruits, and though parasites 

 may be quite numerous among some of the wild fruits, yet they are not able to 

 injure the larvae in large fruits. 



In Mexico an ichneumonid parasite infests the Morelos orange 

 worm [Tnjpeta Judens Loew). namely, Cratospila rudibiindo Say, 

 though, as stated by Mr. Isaacs, not over from 10 to 15 per cent are 

 parasitized. Prof. A. Berlese records IJexameroeera hrasUiensis 

 Ashm. MS. from the Mediterranean fruit-fly, and its use has been 

 advocated by Yon Ihering against Trypeta In dens. 



PREVENTIVE AXD REMEDIAL MEASURES. 



The governments oi certain countries have put in force regulations 

 for the enforced control of fruit-flies, and in each instance the prin- 

 ciple followed has been the inspection of orchards and cleaning up 

 and destruction of all fallen fruits. This seems to be the plan 

 principally recommended and relied upon for the control of this in- 



