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may be covered with the scars of many ovipositions by different 

 females. These eggs hatch after from 2 to 4 days, the larvae 

 immediately beginning to eat their way into the fruit. In summer the 

 larval period averages from 12 to 15 days ; this may be prolonged 

 to several weeks in winter. When fully developed the larvae leave 

 the fruit and burrow into the soil to a depth of 2 or 3 inches, where 

 they pupate. If burrowing is not practicable, the pupa may be 

 situated under any convenient object or even in an exposed position. 

 The pupal period varies from 12 days to several weeks according to 

 the temperature. The adults normally feed on fruit- juices, sap or 

 honey-dew. If supplied with food they have been kept alive for 

 more than three months, and this period may be greatly prolonged 

 under favourable conditions. Mating frequently occurs on the first 

 day after emergence, oviposition usually beginning about the seventh 

 day or earlier and continuing for a long period, an average female 

 probable depositing between 500 and 800 eggs. 



The fruits attacked and more or less completely destroyed b}' 

 A. fraterculus include : Guava {Psidium gimjava), coffee berries, pear,, 

 peach, mango, orange, Eiigenia spp., Phylocalyx, Japanese plum, 

 Japanese persimmon, Para plum, and Anona humboldtiana. In 

 addition, the author has found infested in northern Argentina, straw- 

 berry guava {Psidium caitleyanum), Chinese guava (P. lucidium), 

 fig {Ficus carica), pomelo {Citrus decumana), kumquat {Citrus japonica) 

 tangerine {Citrus nobilis), apricot {Prunus armeniaca), avocado {Persea 

 americana), chirimoya {Anona cherimola). Lemons have several 

 times been found punctured by the fly, though no larvae have been 

 known to develop in them. 



In Argentina, apricots are first attacked in the spring, and then 

 peaches, which may be regarded as the principal summer host of the 

 insect. Both adults that have survived the colder months and those 

 that have emerged from hibernating larvae or pupae oviposit in early 

 apricots and rapidly develop, giving rise to more adults that are ready 

 to attack the first peaches, many of which are punctured when not 

 much more than half-grown. These peaches mummify and sometimes 

 drop but do not furnish nourishment for the larvae to develop. In 

 fruit that is attacked two or three weeks before ripening, the larvae 

 develop rapidly, eating out a large part of the flesh and causing the 

 remainder of the peach to rot. If the fruit falls the larvae generally 

 complete their development in the fruit as it lies on the ground. The 

 life-cycle may be completed in about three weeks in summer under 

 favourable conditions of food and-temperature, though the usual time 

 is about 30 days. By the end of the peach season, the flies have reached 

 their maximum number and there is scarcely enough fruit for all 

 the females to oviposit in, with the result that any kind of fruit is 

 used for this purpose although the larvae can only develop in certain 

 kinds. After the peaches have all been destroyed, later fruits such as 

 chirimoyas and guavas each serve as host for one generation of the 

 insect. ' Persimmons help the flies to survive until oranges are ripe 

 for attack, which is generally from early March until the end of 

 April. Numbers of eggs deposited in oranges are destroyed by 

 the essential oils liberated in the orange peel by the puncture of 

 the fly, while many larvae starve to death before they can penetrate the 

 thick rind and reach the pulp that they require for nourishment. 



