312 Journal of Agricultural Research voi. in. No. 4 



decayed oranges received at London from St. Michael. Villeneuve (1859) 

 exhibited before the Entomological Society of France an infested orange 

 from Algeria, and Laboulbene (1871) describes the injuries caused by the 

 fruit fly to oranges in Algeria and quotes from notes furnished him by 

 Boisduval to the effect that at Bildah and in all Algeria the orange crop 

 was completely destroyed by the insect. On the other hand, Rondani 

 (1870) writes that the species is rare in Spain and is found in Italy only 

 in the southern part. 



While the purpose of this article is not to record the Hterature of this 

 fruit fly, these few references are sufficient to show that much of the early 

 literature greatly emphasizes the destructiveness of the Mediterranean 

 fruit fly to citrous fruits and has laid little stress upon other fruits more 

 susceptible to attack. It is also interesting to note that much of this 

 older literature, which has been generously copied by later writers, records 

 damage to citrous crops grown in very equable climates and in localities 

 where presumably, as in the Hawaiian Islands, there are many host 

 fruits whose commercial value was so small that they escaped the notice 

 of these writers, who judged of the seriousness of the pest by the fruits 

 arriving at their home markets or from common reports. It is also very 

 possible, with our more exact knowledge of the causes of the decay of 

 fruit in transit and of the wholesale shedding of citrous fruits in the field, 

 due to several fungous diseases, to question the reliability of some of the 

 earlier statements. 



HOST FRUITS 



Apparently the first obser\-er who did not entirely agree with Mac- 

 Leay's statement that whenever a puncture is found in the rind of the 

 orange "there is a worm concealed in the interior" is Laboulbene, who 

 said that when he compared his observations on the damage done to 

 oranges by the Mediterranean fruit fly with those recorded by others he 

 found certain contradictory facts which needed further investigation. 

 These contradictory facts, although Laboulbene did not know it, were 

 concerned with what has been determined by the writers as an excessive 

 mortality occurring among the eggs and lar\'se of the Mediterranean 

 fruit fly in the orange rind. This mortality, which in the examination of 

 39 grapefruit that were yellow in color amounted to 99.7 per cent of 7,722 

 forms, as shown in Table I, will prove a very effective factor in checking 

 this pest in the citrous regions of the United States, especially when com- 

 bined with the climatic and floral characteristics of these citrous regions 

 and the method of growing and harvesting the fruit. 



