366 Journal of Agricultural Research voi. m. no. $ 



It was found that in Bermuda, when the monthly means range from 

 62.5° to 64.8° F., the pupal stage was lengthened to about 31 days under 

 normal conditions. The writers have found that the Mediterranean 

 fruit fly can pass from egg to adult if kept in the dark in cold storage at 

 56° to 57° and that at this temperature practically all pupse yield adults 

 from 37 to 41 days after pupation. Pupae placed in cold storage in the 

 light at a temperature varying between 58° and 62° were apparently 

 unafiFected by the cold, except that the length of the stage was increased 

 to from 29 to 31 days for pupse which were about 3 hours old when 

 placed in cold storage. In carrying pupae from place to place for rearing 

 purposes a temperature of less than 56° to 60° is not advised, as great 

 mortality occurs. Thus, from about 300 pupae i day old placed in cold 

 storage at about 50° on June 2 and removed to a normal summer tem- 

 perature at Honolulu on July 22 only 8 adults emerged during the period 

 from July 24 to 26. 



ADULTS 



The adults of the Mediterranean fruit fly emerge in largest numbers 

 early in the morning during warm weather and more scatteringly during 

 cool weather. 



CARE OF ADULTS 



As adults die in greatest numbers within 48 hours after emergence, or 

 within 72 hours at the longest, if food is not given them, those required 

 for future observations must be transferred to a place where they may 

 be fed and cared for daily. In this work the writers have found glass 

 jars 9 by 12K inches covered with cheesecloth very convenient. Such 

 jars will hold from 200 to 300 flies in good condition. Fruit juices of 

 almost any sort are eagerly eaten. Water slightly sweetened with pine- 

 apple {Ananas ananas) syrup was used with good results by the writers for 

 many months, but was replaced later by a mixture of water and finely di- 

 vided parts of papaya {Carica papaya) . When fed with such diluted food, 

 adults thrive best on two feedings a day, one in the morning and one late in 

 the afternoon. The food may be applied in finely di\'ided drops to the sides 

 of thejar by flirting the mixture forcibly against the cheesecloth covering 

 by means of a snapping movement of the thumb and forefinger. The 

 adults feed greedil}' and soon become distended. In this condition 

 many fall and rest upon the bottom of the jar; hence, the less food falling 

 on this portion of the jar the fewer will be the deaths resulting from 

 entanglement in it. If the flies are not required for oviposition, they 

 can be kept alive far more easily by suspending within the jar a juicy 

 fruit upon which they may feed. One mango, the skin of which had 

 been broken in numerous places, served to keep alive from 100 to 200 

 flies for one week. Feeding by flirting mixtures through the cloth co\'er- 

 ing causes the sides of the jar to become soiled quickly and necessitates 



