400 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 6 



When the eggs are deposited within the pulp of ripe tropical almonds 

 they hatch in from 2 to 3 days but when deposited in green fruits the 

 egg period is often somewhat prolonged. 



Larv^. — Eggs deposited in some green fruits either do not develop 

 or the recently hatched larvae perish apparently from the effects of 

 the strong acid pulp of the fruit. The larvae, however, are able to 

 develop in unripe tropical almonds and peaches. Concerning the 

 development of the eggs and larvae in green Chinese bananas we 

 (4, p. 446) found that of 100 eggs planted within the peel 69 hatched, 

 but all of the maggots died, probably from the effects of the tannic 

 acid. Many eggs deposited in green and ripe lemons (Citrus medica 

 limonum) hatched but in our observations all of the maggots died. 

 French (2, p. 3) of Victoria and Mally (3, p. 5) of South Africa have 

 both, however, succeeded in breeding the Mediterranean fruit fly 

 from lemons. Whether the maggots of this pest are able to complete 

 their larval development in certain varieties of lemons and not in 

 others will require further investigation. 



The larvae work their way into the pulp of the fruit, which soon be- 

 gins to decay (Plate 9, figures 5, 6, 7, 8 and 9) and the fruit usually 

 drops to the ground. On rare occasions the dried and shriveled fruit 

 will remain adhering to the trees after all of the larvae have burrowed 

 out (Plate 10, figures 15 and 16). It may happen that some of the 

 maggots will bore out of the fruit before the same drops to the ground. 



The larvae remain in the tropical almond from 8 to 17 days after 

 which they bore out and enter the ground to pupate. The rate of 

 development of the maggots probably depends on many factors, such 

 as temperature, moisture, the kind, ripeness, hardness, decay, dryness, 

 and acidity of the fruit. 



Data were desired concerning the number of Mediterranean fruit 

 fly larvae which may be found infesting tropical almonds. Accordingly, 

 25 infested tropical almonds were gathered at random from a tree and 

 placed in 25 breeding jars. In two weeks a total of 1037 fruit fly maggots 

 had bored out of the pulp of these fruits. Each tropical almond was 

 now immersed in water so as to drown out any larvae which might 

 still be present in the pulp or fibrous shell of the nut. With the addi- 

 tion of a small quantity of alcohol to the water the maggots leave the 

 fruit more rapidly and within five hours 341 immature fruit fly larvae 

 burrowed out of the decayed pulp. The pulp of each fruit was now 

 carefully removed and two maggots were found within the fibrous shell. 

 The total number of full grown and immature larvae obtained from 

 25 tropical almonds was 1380. The largest number of full grown mag- 

 gots obtained from a single tropical almond was 98, of these 60 were 

 full grown and 38 immature. One would be inclined to believe that 



