G7 



America, Mr. Lonnsbury took an extended trip down th3 South American 

 coast, but found even worse conditions in fruit-fly infestation than he had in 

 South Africa. In the district round Bahia, described by the West Australian 

 entomologist as being "the fruit district of Brazil" and yet almost free from 

 fruit-flies on account of parasites, Lounsbury said he found no commercial 

 orchards ; and speaking of the Brazilian cherry he says : " My impression is 

 that nearly every fruit g^ts punctured if allowed to fully ripen upon the 

 plant." Mr. Fuller counted 280 puparia from one lot of pilangas he gathered, 

 and from them emerged 124 adult fruit-flies and 77 parasites; from another 

 lot he collected on llth March in the same locality he obtained 141 puparia, 

 and from these emerged 47 fruit-flies and 28 parasites. The latter consisted 

 of 221 fruits large and small, ripe and unripe shaken from the bushes. 

 The extent of parasitism in both cases works out at about 38 per cent. 



The parasite is a minute wasp (Opiellus trimiculatus). Fuller says : "The 

 effective parasitism of this species reaches its maximum in small fruits with 

 thin pulp, and the effectiveness falls appreciably in proportion to the depth 

 or thickness of the pulp of the fruit attacked by the Hy." 



None of these hymenopterous parasites, though so abundant, were con- 

 sidered sufficiently effective, and no efforts were made to introduce them into 

 Africa. It was the Staphylinid beetle that these investigators had gone to 

 procure, but with careful search they could not find any. It may have been 

 the wrong season, but it does not say much for the parasite if the fruit-flies, 

 were busy all the year and the beetles only a few months. In fact, the 

 case was that the fruit had to become rotten with fruit-fly maggots, and fall 

 to the ground before the predaceous scavenger beetles could take a hand in 

 the destruction of the maggots. 



Messrs. Lounsbury and Fuller returned to South Africa without getting a 

 single effective parasite, or even seeing a Staphylinid beetle at work in the 

 orchards, and Mr. Fuller's remarks in the journal of the Natal Department 

 of Agriculture are even more emphatic than Mr. Lounsbury's in their 

 condemnation of the Staphylinid beetle. 



Yet, in his report, " Introduction of the Fruit-fly Parasite (Journal of the 

 Department of Agriculture, 1904), Mr. Compere concluded with the follow- 

 ing statement : " The Staphylinidse beetles beyond question destroy the 

 major part of the fruit-fly maggots in Brazil, and also destroy a great number 

 of parasites as well, eating every maggot with which they como in contact, 

 not discriminating between those parasitised and those that are not." He 

 says, too : " In Brazil, the same as in India, nature's forces controlling these 

 destructive fruit-flies is complete." Only a few months later Lounsbury and 

 Fuller found that all down the Brazilian coast it was difficult to obtain a 

 fruit that had not been punctured by a fly. The officers of the West 

 Australian Department of Agriculture have known quite well for some 

 years that this beetle is not only no check upon fruit-fly in the West 

 Australian orchard", but that it had never even been established outside 

 their insectarium, and there they died out ; yet they still publish glowing 

 accounts of its value, as can be seen in their official bulletin, " The Selector's 

 Guide to the Crown Lands of Western Australia." On pige 20, the 

 successful introduction is stated as a fact. " Fruit Pests : Successful Work 

 of the State Entomologist." Now, in regard to the statement that nature 

 controls the destructive fruit-flies in India, if it means that they are kept 

 below the point where they become a pest, it is certainly not true. 



The fruit-flies of the genus Dacus, belonging to several specie.", are so 

 abundant in all the fruit-growing districts of India and Ceylon, that 



