252 Journal of Agricultural Research voi. vi, no. 7 



another instance the same investigator records finding a living adult of 

 the olive fruit fly (Dacus oleae Rossi) and a dead adult of another species 

 of fruit fly, apparently Dacus semispharens Becker. Both of these species 

 were in a small package containing olive seed from Cape Town, South 

 Africa, after having been en route 28 days. Sasscer states that according 

 to Silvestri it requires from 47 to 49 days in Italy for the pupae of the 

 olive fruit fly to yield adults; hence, it is possible for this ruinous pest to 

 enter the United States through the eastern ports as pupae and reach the 

 olive-growing sections of California before adults have emerged. 



Such facts as these indicate that the Mediterranean fruit fly may be 

 similarly transported, and emphasize the desirability of recorded data 

 on the effect of cold-storage temperatures upon the pupal stages. Aside 

 from the practical application in the future to quarantines regulating the 

 shipment of fruits, the results given below throw considerable light on 

 conditions governing the distribution of the pest, and help explain the 

 varying severity of its ravages in countries having both semitropical and 

 temperate fruit-growing regions. 



HISTORICAL REVIEW 



Practically nothing has been published on the effect of cold-storage 

 temperatures upon the pupae of Ceratitis capitata. In 1908 Lounsbury * 

 in South Africa reports that in removing fruit infested with C. capitata 

 from refrigeration at 38° to 40° F. at the end of 21 and 27 days he found 

 in each instance a single pupa, but that both proved to be dead. The 

 experiments of the writers have demonstrated that these two pupae were 

 produced by larvae which formed their puparia before the fruit was placed 

 in storage, as larvae do not form puparia at temperatures lower than 

 45° to 48° F. 



In 1914 Newman,^ in Western Australia, placed one box containing 50 



newly formed puparia in each of four rooms held, respectively, at 32°, 



36°, 45°, and 55° F. At the end of 34 days of refrigeration 25 pupae were 



taken from each box held at 32° and 36°, and at the end of 70 days of 



refrigeration the remaining pupae held at 32° and 36° and all held at 45° 



and 55° were removed to the laboratory. None of the pupae removed 



yielded adults. 



EXPERIMENTAL WORK 



Nearly all the experimental work with temperatures lower than 45° F. 

 was carried on in a thoroughly modern three-story cold-storage plant. 

 The temperatures of the rooms in this plant were held quite definitely 

 within certain fixed ranges by hourly inspections made by the storage 

 employees. One experiment was carried on in a second plant where, as 

 indicated in the text, the temperature was subject to considerable fluc- 



' Lounsbury, C. P. Report of the Government Entomologist, Cape of Good Hope, 1907, p. 56. 1908. 

 ^ Newman, L. J. Annual report of the officer in charge of the insectary for the year ended June 30, 1914. 

 In Ann. Rpt. Dept. Agr. West. Aust. 1914, p. 61. 1915. 



