176 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 9 



As the result of this importation, there has been a very great in- 

 crease in the sugar yield per acre. The gain runs into the hundreds 

 of thousands of dollars. 



The adult tachinid places her eggs at openings in the rind of the 

 cane where the borer larvse feeding inside have come to the surface. 

 The maggots find the borer larvse in the channels, penetrate the body 

 and kill the host when it is about ready to pupate. From one to a 

 dozen maggots may thrive in one borer larva, but one is sufficient to 

 kill it. The puparia are found in the fibrous cocoon made by the 

 full-grown borer larva. The flies on issuing make their way through 

 the cocoon and out of the cane through the hole which the borer 

 larva had previously made. 



The Meditereanean Fruit-Fly and its Introduced Parasites 



The Mediterranean fruit-fly has been present in Hawaii since some 

 time prior to 1910, and has practically stopped the growing of fruit 

 except pineapples and bananas, although some sound mangoes and 

 alligator pears are still raised. 



On account of the occurrence of enormous quantities of wild guava 

 bushes all over the mountains, the extermination of the fly or even 

 its great reduction in numbers seems to be impossible. The destruc- 

 tion of the fallen fruit afforded little relief. Poisoning experiments, 

 although somewhat successful, could not control, on account of the 

 enormous wild suppl3^ 



Silvestri, by his favorable report on the work of the Sugar Planters' 

 Association in the introduction of parasites of the leaf-hopper, achieved 

 the good will and admiration of the Hawaiian people, notably Mr. 

 W. M. Giffard, Chairman of the Entomological Committee of the 

 Sugar Planters' Association and President of the Hawaiian Board of 

 Agriculture and Forestry. He therefore asked Silvestri to search for 

 parasites of the fruit-fly and to introduce them into Hawaii. Silvestri 

 started July 25, 1912, and visited the Canary Islands, Senegal, French 

 Guinea, Southern Nigeria, Gold Coast, Dahomey, Congo, Angola, 

 and South Africa; then, by way of Australia, he went to Honolulu, 

 arriving May 16, 1913. 



He brought with him from West Africa, having continuously reared 

 them through the journey, 300 specimens of Galesus silvestrii Kieffer, 

 500 specimens of Dirhinus giffardi Silvestri, 12 specimens of Opius 

 perproximus Silvestri, 5 specimens of Opius humilis Silvestri, and 4 

 females and 3 males of Diachasma tryoni Cameron. The rearing of 

 these was begun by ]\Ir. D, T. Fullaway until September 30, and then 

 by Mr. J. C. Bridwell from October 1 to December 31, 1913. It was 

 found not very difficult to rear some of them in confinement. The 



