224 DIPTERA OR TRUE FLIES. 



as in Europe. Diseased pears become distorted about the time 

 they are slightly larger than the size of a hazel-nut, presenting a 

 well-marked appearance by which they can be always detected. 

 The fly (fig. 121) is a minute midge about the size of the wheat 

 midge, but blackish-grey in colour. The female lays her eggs in 

 the unopened blossoms, just when the petals commence to show 

 themselves. Sometimes I have observed them oviposit in the 

 opened blossoms. The white larvse feed off the upper parts of 

 the young fruit first, and by degrees turn the inside black and 

 hollow it out : as many as sixty larvfe may frequently be found 



<Hfla;ia> 



Pin. 121.— The Pear Midoe. 



1, Pear stunted and malformed by the larvfe within it; 2, section of pear with 

 larvfi-; 3, larva, much magnified; 4, female fly, much magnified. Lines show 

 natural length of fly and larva. (From U.S.A. Dept Agriculture.) 



in one fruitlet. The pears are thus completely destroyed. The 

 maggots rarely pupate inside the dead pear, which turns black 

 and shrivels up ; generally they escape into the ground. The 

 fly is about one-twelfth of an inch long and greyish-black in 

 colour, with pale-brown antennae, and abdomen covered with 

 pale hairs. Wings hairy, and halteres yellow, with white 

 knobs. The eggs hatch in four to six days. The maggots 

 are creamy -white, about one -seventh of an inch long, and 

 commence to reach maturity about the first week in June. 

 They may, I find, stay in the dead peav for some time; but 

 eventually they get into the ground, where they form little cells 

 to pupate in. All varieties of pears suffer to some extent. 



