MEDITERRANEAN FRUIT FLY IN HAWAII. 61 



Pupae formed by larvae pupating within a refrigerator held at 52 to 56° F. yielded 

 2 and 1 adults within storage after refrigeration for 38 and 52 days, respectively. Out 

 of 39,500 pupae held in like manner at from 49 to 51° F. only 1, 2, 2, 3, and 1 pupae 

 yielded adults in storage after 20, 23, 44, 46, and 47 days, respectively, of refrigeration. 

 These 9 pupae yielding adults were 5 days old when placed in cool storage ; hence they 

 were 25, 28, 49, 51, and 52 days old when they yielded adults. One 3-day-old pupa 

 held at an even temperature of 32° F. for 9 days, on removal to normal temperature 

 produced an adult on November 14, 10 days later, or when 23 days old. Two 1-day- 

 old pupae refrigerated for 19 days and then removed to normal temperatures yielded 

 adults in 29 and 30 days, respectively, after pupation. Investigators working in 

 countries where the temperature falls for short periods to or slightly below freezing 

 are referred for other data to a previous paper by the writers x in which are given 

 data on the effects of 32°, 33° to 34°, 33° to 36°, 28° to 40°, 38° to 40°, 40° to 45°, 

 49° to 51°, 52° to 56°, and 54° to 57° F. upon 173,318 pupae. 



During January-March, 1915, the writers secured data on the effect upon the dura- 

 tion of pupal life of out-of-door temperatures at elevations of about 3,700 feet at Straw- 

 berry, at 5,000 feet at Puulehua, and on Mauna Hualalai at 8,250 feet. Pupae formed 

 at Honolulu on January 31, shipped to Kealakekua on February 9-10, and placed at 

 Strawberry on February 11, were found to have produced 1, 72, 392, 4, and 6 adults 

 on February 24, 25, 27, and March 3. The temperature at Strawberry for these periods 

 ranged from 42 to 69° F. with a mean of about 56° F. Other pupae formed at Honolulu 

 on February 8, shipped to Kealakekua February 9-10, and placed at Strawberry 

 February 11, were found to have yielded 3, 307, 503, and 13 adults on March 11, 17, 

 20, and 25, respectively. Pupae formed at Honolulu on February 6, shipped to 

 Kealakekua February 9-10, placed at Puulekua February 11, where the temperature 

 between February 11 and March 26 ranged from 38° F. to 72° F., with a mean of 53° 

 to 54° F., were found to have yielded 2, 10, 108, 126, and 13 adults on March 9, 17, 

 20, 25, and 26, respectively. The pupae yielding adults on March 26 were 48 days 

 old. Other pupae formed at Kealakekua on January 26 and taken the same day to 

 Puulehua yielded no adults before March 25, when they were removed to Kealakekua, 

 where the temperature ranged during March 24-27 between 60 and 84° F. At 

 Kealakekua 2 and 16 pupae yielded adults on March 26 and 27, respectively, or when 

 59 and 60 days old. Pupae formed at Honolulu February 12, shipped to Kealakekua 

 February 17, and placed at Puulehua February 24, were found to have yielded 4, 96, 

 and 1 adults on March 9, 17, and 20, respectively. Pupae formed at Kealakekua 

 January 27, taken to Hualalai January 31, and removed to Kealakekua March 26, pro- 

 duced no adults, and on examination appeared not to have been able actually to 

 pupate. The temperature on Hualalai for the period ranged between 31° and 70° F. 

 Pupae formed at Honolulu February 9, placed on Hualalai February 12, and removed 

 to Kealakekua March 2, yielded 10 adults between March 17 and 20, or when 36 to 39 

 days of age. Pupae formed at Honolulu February 5 and taken to Hualalai February 11 

 were found to have yielded 51 adults between March 23 and 26. On March 26 they were 

 removed to Kealakekua, where 17 and 2 yielded adults on March 27 and 28, respec- 

 tively, or 50 and 51 days after pupation. Of this lot of pupae, 1,820 did not survive 

 the Hualalai temperature. Pupae formed at Honolulu February 7, placed on Hualalai 

 February 12, and removed to Kealakekua March 26, yielded 52 adults on March 31, 

 or 52 days after pupation, but 1,506 failed to survive. 



The data presented are of particular interest in bringing out the ability of pupae to 

 survive various climatic conditions apt to be experienced in countries harboring fruit 

 flies. It will be noted that 60 days is the longest period obtained by the writers for 

 pupal development. 



1 Back, E. A., and Pemberton, C. E. Effect of cold-storage temperatures upon the pupae of the Medi- 

 terranean fruit fly. Jour. Agr. Research, v. 6, no. 7, 1916, p. 251-260. 



