148 



ST. HELENA 



pears in his garden at Peckham. It was no doubt imported, and 

 established itself for a short time only. 



The question of the specific identity or not of the forms found 

 in different countries is of no immediate moment, but is of import- 

 ance as regards the distribution of the species and any variation in 

 habits which may characterize them. 



The fruits on which attacks have been observed are the orange, 

 lemon and other species of citrus, the peach, apricot, plum, Surinam 

 cherry, the fig, the pear, and possibly the apple. With regard to 

 the last mentioned confusion with an allied species of fly may have 

 arisen. 



Attack on very young fruit, as mentioned in the letter of the 

 Acting-Governor of St. Helena, appears to be unusual. An African 

 grower, Mr. J. B. Hellier, in a, letter from Grahamstown, quoted by 

 Miss Ormerod, says : — " The perfect insect maybe'seen flying about 

 very swiftly, and depositing some half-dozen eggs in a fruit. They 

 do not deposit their eggs till the fruit is turning, that is, getting 

 sweet. The maggots are never found in green apricots used for 

 making pies, neither are they found in sour apples." 



In some districts one or other fruit escapes. " The oranges 

 at Uitenhage (South Africa) in October and November, 1886, were 

 infested and maggoty, but the apricots and peaches which came 

 ripe in December and January, were comparatively free." 



On the contrary, in Liguria, in 1882, the fly was observed to 

 damage peaches, but its presence in oranges or lemons was not 

 verified. 



This is likely to depend on the respective degrees of ripeness 

 of the fruit at the time of the oviposition of the flies. On this 

 latter point, and on the time passed by the fly in its various stages, 

 and on the number of broods in the year, there is not sufficient 

 ■ information ; and these circumstances are likely to vary in country 

 and climate, and should be ascertained on the spot. 



Professor Riley wrote with reference to attack on peaches in 

 May in Bermuda : — " With our knowledge of the habits of the insect, 

 derived from writings of those who have mentioned it as an orange 

 pest, it seems altogether likely that there is more than one genera- 

 tion, and that the flies issuing from peaches in May oviposit in 

 some other fruit, and in this event the destruction of the peaches 

 will only prove a partial remedy, unless it should turn out that a 

 generation in the peach at this time is necessary to fill a gap in 

 point of time in the life-history of the insect. He adds that, judging 

 from the rapid development, there should be six or eight generations 

 in the course of a season, provided that food is at hand. 



Few additional details of importance as to the life-history of 

 the inseot are to be gathered from those who have written on it. 

 It appears that the egg is laid by the fly within the skin of the 

 fruit at a depth of one to three millim. ; and this appears to exclude 

 the use of arsenical insecticides, which have been so largely em- 

 ployed to prevent the somewhat similar mischief caused by the 

 oodlin moth, the larva of which, however, has to bore its way 



