CITRUS FRUIT INSECTS IN MEDITERRANEAN COUNTRIES. 9 



were taken in this grove, but four were taken in three other places. 

 Two out of the 10 taken during the week were on the tree, while the 

 remainder were on the ground. It should be stated that the two 

 taken from the tree were also partly decayed on one side. The 

 decay in most of these lemons appeared not to be due entirely to 

 the fruit-fly. No punctures were seen, and it is assumed that the 

 eggs were deposited in the decayed side, or else the decay which set in 

 later completely obliterated the punctures. One more lemon with 

 fruit-fly larvae was found during the fifth week, making a total of 

 15 infested lemons out of the thousands examined. None was 

 found during the remaining three weeks of the inspection. None of 

 the infested lemons would have been considered for shipment, and 

 with three or four exceptions would not have been taken for the by- 

 product factory. In some of the lemons, it is true, the larvae were 

 nearly grown, and the condition of the fruit can not be vouched 

 for at the time of oviposition, but in others the larvae were but 

 partly grown, and thus the fruit had not been long infested. 1 



EXPERIMENTS WITH THE FRUIT -FLY. 



Through the kindness of the Prince of Galati use was had of a 

 neglected garden within the city of Palermo, and under a tree 

 here was equipped an improvised laboratory. (PI. X, fig. 5.) Three 

 series of experiments were carried on. The first series was to deter- 

 mine if it is possible to transfer the larvae of Ceratitis from other 

 fruits into the lemon and bring them to maturity. The idea was 

 generally held in Italy, even by the entomologists, that the lemon 

 is too bitter or acid for the fruit-fly. The second series was to 

 determine the possible extent of oviposition on lemons in confine- 

 ment, and the third as a check on the second series and for life- 

 history work, and to determine the extent of breeding in other fruits, 

 as the apple, pear, peach, and orange, under the same conditions. 



To summarize briefly, the first series of experiments resulted in 

 establishing the fact that it is possible to transfer fruit-fly larvae 

 from a fine ripe peach to a ripe and also to a perfectly green lemon 

 and bring them to maturity. The second series, so far as the experi- 

 ments were conducted in small glass containers, resulted negatively. 

 The third series resulted in securing oviposition and development 

 in the peach, pear, and orange. 



In the first set of experiments a small plug was cut out of the rind 

 of the lemon, and a small cavity made in the pulp, just large enough 

 to contain the larvae. After the larvae were transferred, the plug 

 of rind was replaced, a small triangular piece first being cut out 

 of one side of the plug for air. Aseptic methods were employed 



1 In Hawaii a perfectly sound lemon has been seen with a single specimen of Ceratitis capitata. In Hawaii, 

 also , Ceratitis punctures in lemons are very common, though actual infestation seems to be rare. 



51981°— Bull. 134—14 2 



