77 



damage by the olive fly totalled 1,000,000. In dealing with this pest, a 

 \vry large reward is offered by the Italian Government for any remedy or 

 method to check the- pest. 



Professor Berlese, the celebrated Italian zoologist, stationed at Florence, 

 has experimented with a sweet poisoned spray, consisting of honey, treacle, 

 arsenic, and water. The formula is 



Mellasa (in English molasses) ... ... ... 40 



Miele (honey) ' 40 



Arsenate of potassi ... 



Aqua (water) ... ... ... ... ... 18 



The spraying of the trees was very successful in the experiments carried 

 out except that it was very easily washed off, and also that in some instances 

 a number of bees were killed. 



The Professor is now experimenting with a similar mixture placed in small 

 bottles hung up on the branches of the trees. Into each bottle is inserted 

 several long cotton threads, forming loose bundles hanging several feet, down 

 which the poisoned liquid flows, and the flies find a ready resting-place while 

 they sip the poison. 



I have written to Professor Berlese, and asked him to try the addition of 

 citronella oil to his poisoned mixture, which he calls Dacacide, and to let me 

 know whether it attracts the olive fly. His assistant informed me, when at 

 his laboratories in Florence, that the majority of the flies killed with Dacacide 

 were males. 



In South Africa, where fruit-flies are probably as bad as any place in the 

 world, fine netting was used to protect the fruit on the trees from the 

 flies, but it was so expensive on a large scale that its use was not extended, 

 and it was only when there was a very valuable crop that it paid. 



Where the orchard is kept in good condition, domestic poultry, particu- 

 larly hens which have the scratching habit highly developed, no doubt, if given 

 the run of the orchard, will unearth a lot of pupae and destroy many in all 

 stages of growth. 



Family Trypetidce . 



All the members of the true fruit-flies are placed in this family of the 

 Diptera, and are classified by most authorities as a division or group known 

 as the Muse idee, which it is not necessary to define here. 



Williston in his "^North American Diptera" (second edition), 1896, gives 

 the following definition : 



" Head hemispherical ; face nearly perpendicular in profile, or somewhat 

 retreating, without distinct vibrissae ; front broad, bristly on the sides, the 

 lower frou to-orbital bristles situated close to the border of the eyes; antennae 

 decumbent, short, rarely elongated ; abdomen, composed of four or five seg- 

 ments ; genitalia of the males but little exposed ; the ovipositor jointed, 

 more or less projecting ; wings rather large ; auxiliary vein present, ending 

 steeply and obscurely in or near the border ; posterior basal cell and the anal 

 cell distinct, the latter often drawn out into an acute, often prolonged, 

 point ; wings usually with dark markings ; legs moderately long ; tibiae 

 without preapical bristle ; proboscis moderately long, usually with broad 

 label'a, sometimes long, and the narrow labella folding backward." 



