18 THE MEDITERRANEAN FRUIT- PLY. 



trees with netting, and in the case of small to medium-sized trees 

 the method was thought to be practical. Full directions were given 

 for the employment of netting, and it was stated: 



The measure will undoubtedly be of great value to parties growing choice 

 varieties in and about our villages where, because of laxity on the part of 

 neighbors, the destruction of all maggot-infested fruit on one's place is un- 

 availing as a preventive from further attack. 



This plan, apparently, has not been followed to any great extent. 



Professor Antonio Berlese, of Florence, Italj^, began in 1903 tests 

 of a i^oisoned bait against the olive fly {Dacus olecv). The poisoned 

 liquid was sprayed over the trees to destroy the adults which feed 

 freely on available fruit juices and other sweetish substances. This 

 work, commenced in 1903, was continued during 1905 and 190G. The 

 material used consisted of honey 31 per cent, molasses G5 per cent, 

 glycerine 2 per cent, and arsenite of potash 2 per cent. Prof. Berlese 

 states : 



I have carried on the above experiments on 16,000 trees in three different 

 localities, and have obtained absolute results, hitving succeeded in keeping 

 sound, until they were ripe, all the olives on the trees which had been treated. 

 This I did. although in the surrounding plantations all the olives were maggot- 

 eaten and destroyed as early as September. Since the mixture is very soluble, 

 the autunnial rains, which fall generally a little before the gathering of the 

 fruit, are sufficient to wash off the poisoned substance, which was sprayed on 

 to the olives. When, however, copious rains do not occur, it is necessary, before 

 sending the olives to the press, to wash them in water in order to prevent any 

 risk of poisoning. 



In the Agricultural Journal, Cape of Good Hope, for December, 

 1904, Mr. C. W. Mally reports upon experiments, made quite inde- 

 pendently of those of Prof. Berlese, in the destruction of the Mediter- 

 ranean fruit-flies by a poisoned-bait spra}', used with good results 

 in his rearing cages. The bait consisted of a solution of 5 gallons of 

 treacle (molasses), 1 pound of arsenate of lead, and 25 gallons of 

 water. This poisoned bait was further tried out by Mally and others 

 during several succeeding seasons, and in 1909 was put to practical 

 field tests. Concerning the experiment Mr. Mally states : 



Results. — While the bait was expected to make a good showing in regard to 

 the late varieties of fruit, its prompt effect in almost completely stopping the 

 deposition of eggs in the fruit already ripening came as an agreeable surprise. 

 The late maturing portion of the fruit on the trees, showing infestation to the 

 extent of 50 per cent of the fruit in the proper stage of ripeness for the flies 

 when the baiting began, came to maturity practically free from maggots — less 

 than 1 per cent being infested. The fruit on all the late varieties of treated 

 trees ripened perfectly, and was sold on the market and guaranteed free from 

 maggots. No complaints of infestation were received at any time. On the 

 control trees the situation was just the reverse, almost every ripe fruit being 

 infested by maggots ranging from newly hatched to fully developed. Tuparia 

 were present under some of the decaying peaches, and there were nuruerous flies 

 flitting about the trees. 



