202 DIPTEEA OK TEUE FLIES. 



size of the wheat midge, but blackish-grey in colour. The 

 female lays her eggs in the unopened blossom buds, 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 

 twenty larvae may frequently be found in one fruitlet. The 

 pears are thus completely destroyed, and fall off. The maggots 

 may pupate inside the dead pear, which turns black and shrivels 

 up, and hatch out in the following spring, but more 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 liairs. Wings hairy, 

 and halteres yellow, with white knobs. The eggs, of which about' 

 a dozen are usually laid in each blossom, hatch in four or five 

 days. The maggots are creamy-white, about one-sixth of an 

 inch long, and commence to reach maturity about the second 

 week in June. They may, I find, stay in the dead pear for 

 some time; but eventually they get into the ground, where 

 they form little cells to pupate in. Perhaps the Marie Louise is 

 most subject to their invasion, but all varieties suffer to some 

 extent. 



Prevention and Remedies. — As far as possible, all infested 

 fruitlets should be destroyed, but this is not always feasible. 

 At present the most successful preventive seems to be kainit 

 spread under the trees after infestation, at the rate of half a 

 ton to the acre (Professor J. B. Smith). If the kainit is used 

 at the time the larvae are falling to the ground, 5 cwt. to the 

 acre is sufficient. Eemoval of the soil for some two inches 

 deep and burning it in the winter would do much good where 

 possible, but it is a troublesome and risky plan, not to be 

 advised except in very local attacks. 



