THE MEDITERRANEAN FRUIT FLY. 



23 



and oranges in astonishingly small numbers because of the imper- 

 viousness of the rag. It is the persistent attack of successive f amilies 

 of larvae hatching from different batches of eggs laid in the same 

 punctures that finally breaks down the barrier between the young 

 larvae and the pulp. A fuller discussion of the infestation of all citrus 

 fruits may be had on application to the Bureau of Entomology. 



Regardless of what has just been stated concerning the great 

 mortality that occurs among the eggs and young larvae in the rind 



Fig. 22. — Cross section of grapefruit to indicate difficulty of always telling from exterior appearance of a 

 fruit that maggots are eating out the pulp. (Authors' illustration. ) 



of grapefruit, oranges, and lemons, adult flies have been reared from 

 them all. Lemons, however, have never been known to be infested 

 in the pulp unless the rind has first become broken by thorn pricks, 

 decays, or in some other mechanical manner. And in spite of the 

 fact that oranges and grapefruit may become very wormy, as illus- 

 trated in figures 2 and 22, they are usually uninfested in the pulp, 

 and are fit for table use if they are gathered as soon as they ripen. 

 But if citrus fruits were grown commercially in Hawah in large 



