PARASITISM OF MEDITEEEANEAN FRUIT FLY IN" HAWAII 5 



Fruits with tough skins which do not break readily when they fall 

 from the trees usually have a very low parasitism by T. gifardianus. 

 Fleshy fruits with comparatively thin skins which are broken easily 

 offer a much better opportunity for the parasite to work. 



The data in Table 3 show the effectiveness of each species of para- 

 site for each host fruit under observation for each month in the year. 

 The percentages of parasitism were figured from the numbers of 

 larvae shown in the columns of the table under the caption ''Number 

 of larvae." The rate of development of host larvae varies in dif- 

 ferent species of fruits and with the season of the year, and exposure 

 of host larvae to attack by parasites ceases when the fruits containing 

 them are collected for records of parasitism. In view of these facts, 

 and since the parasites attack only w^ell-developed fruit-fly larvae, 

 the numbers of larvae shown in these columns from which parasitism 

 records were made are larvae emerging from fruits during the first 

 two to six days after collection. 



