84 



BULLETIN 536, U. S. DEPARTMENT OF AGRICULTURE. 



&Pm 



new to science. Silvestri reported having reared giffardii during the 

 period November, 1912, to February, 1913, from Ceratitis antistictica 

 and 0. giffardii at Olokemeji, Southern Nigeria; from C. giffardii at 

 Kotonou, Dahomey, and from Dacus bipartitus at Victoria, Kamerun. 

 Silvestri was unable to keep adults alive during the passage from 

 West Africa to Honolulu. 



In March, 1915, Silvestri published the description of T. giffardi- 

 anus, stating that previous to then he had confused the species with 

 giffardii. T. giffardianus was reared by Silvestri from Ceratitis 

 giffardii Bezzi, collected at Olokemeji, southern Nigeria, and at 

 Kotonou, Dahomey. 



It was T. giffardianus Silv. and not T. giffardii that was collected 

 by the Fullaway-Bridwell expedition and introduced into Hawaii at 



Honolulu on October 27, 1914. This 

 fact should be borne in mind, because 

 much of the literature dealing with 

 parasites of C. capitata in Hawaii refers 

 to T. giffardianus as T. giffardii. 

 References to Tetrastichus as a para- 

 site of Ceratitis capitata in Hawaii 

 should be interpreted to refer only to 

 T. giffardianus. 



Fullaway introduced into the Ha- 

 waiian Islands 300 living specimens of 

 both sexes of T. giffardianus. By De- 

 cember 31, or after about two months 

 of breeding in the laboratory, these 

 300 had increased to 21,431 specimens. 

 Of these, 18,050 = were liberated on 

 Oahu, Hawaii, and Kauai by Janu- 

 ary 1, 1915. Although many thousand 

 specimens have been liberated since De- 

 cember, 1914, none had been recovered as late as February, 1916, 

 from any island except Oahu. 1 In Honolulu specimens have been 

 reared from widely separated points, which would seem to indicate 

 that this parasite has been established successfully. The first recov- 

 eries were made by the writers during September, 1915, in Honolulu. 



DESCRIPTION. 



Adult. — Both sexes of the adult are black with a slightly dark- 

 green iridescence. The antennae are rather dark, as are also the 



1 Exception: One lot of 46 pupae of C. capitata from coffee cherries collected June 18, 1915, at Kainaliu, 

 Hawaii, showed a parasitism of 63 per cent by Opius humilis, 30.4 per cent by Diachasma tryoni, and 2.1 

 per cent by Tetrastichus giffardii. 



Fig. 17.— Tetrastichus giffardianus: a, Ven- 

 tral view of mature larva; b, dorsal view 

 of same, showing spiracles; c, mouth 

 hooks or man dibles; d, egg. Greatly 

 enlarged. (Original.) 



