Feb. IS. 1915 Mediterranean Fruit Fly 367 



the changing of adults to clean jars every two or three days. When fed 

 with suspended fruit, the flies require no changing for at least two weeks. 

 Mortality among the flies increases rapidly in badly soiled jars. 



LENGTH OF LIFE 



Well-fed Mediterranean fruit flies have been kept alive in these jars 

 more than five months. One fly that emerged on December 31, 1913, 

 lived until May 11, 1914, or 131 days. Other flies, which emerged on 

 February 28, 1914, are alive at the date of this writing — August i. 

 Usually about 50 per cent of the flies may be expected to die during the 

 first two months after emergence. When the monthly mean tempera- 

 ture averages about 76° to 79° F., comparatively few flies live to be more 

 than 3 months old. When kept at a temperature ranging from 58° to 

 63°, the writers believe from accumulating data, that especially strong 

 adults will live to be more than 6 months old. 



SEXUAL M.\TURITY 



Neither male nor female flies are sexually mature when they emerge 

 from the pupa. Males show sexual activity often four days after emerg- 

 ence, and copulation has been observed five days after emergence. When 

 the daily mean temperature averages from 76° to 78° F., the larger per- 

 centage of females is ready to mate from six to eight days after eclosion. 

 Adults that emerged on May 23 and 24 and were placed on May 25 in 

 the light in cold storage at 61° to 64° were not observed to mate until 

 June 5, when 14 days old. Copulation may occur at any time throughout 

 the day. 



OVII'oSITION 



Oviposition may take place in Hawaii as early as 5 days after emergence 

 during very warm weather, but not for about 10 days when the tempera- 

 ture ranges between 68° and 72° F. At mean temperatures above 74° 

 various lots of adults will yield large numbers of eggs from 7 to 8 days 

 after emergence. Adults oviposit best at temperatures varj'ing from 70° 

 .upward, but have been observed depositing eggs at 65° to 67°, and in 

 cold storage in the light at about 62°. 



It is impossible at this writing (August 1,1914) to state the full capacity 

 for egg deposition possessed by females of this species. The number of 

 eggs found at any time in the reproductive organs is no indication of the 

 total number of eggs an individual female is capable of depositing, for new 

 eggs are being formed continually throughout life. The data in Table II 

 show that during the first 18 weeks of her life one adult deposited 499 

 eggs and was still in a thrifty condition. Two other females during the 

 same time deposited 416 and 336 eggs, respectively. A fourth female 

 living but 80 days deposited 312 eggs. Usually females die soon after 



