PEARS. 



207 



Ifc seems that certain seasons, or other unknown climatic 

 influences, are favourable to the propagation of certain species of 

 insects. So much is this the case that at times the insects 

 seriously threaten the crop, and their attacks are so persistent as 

 to baffle the gardener's most patient and plucky attempts to 

 defeat them. And no sooner has one become familiar with the 

 habits and compassed the destruction of one species, than probably 

 in the very next season another kind of insect springs into 

 existence, and in numbers quite overwhelming, and of totally 

 different habits. We have already had considerable experience 

 with the winter moth (Chcimatobia brumata) and his allied 

 species, but we have so far conquered him and been able to cope 

 with his attacks, either by the precaution of grease-banding the 

 trunks of the trees in the winter or by spraying the leaves in the 

 spring with a solution of " Paris green." 



Our latest and most formidable foe, although less significant 

 in appearance, whom we have had to battle with the last two 

 seasons, and so far without the least sign of success, is a small 

 gnat-like fly, or midge, named Diplosis pyricora, or Ceci- 

 domyia nigra of some entomologists. I have consulted some 

 of the best authorities on entomology, and very valuable infor- 

 mation has been supplied by Miss Ormerod, Mr. Whitehead, of 

 the Board of Agriculture, and others. Professor Riley, in some 

 official reports, quotes the observations of Schmidberger, who 

 says: " The number of eggs these midges lay varies from one to 

 thirty, which hatch in warm weather in four days from being 

 laid. A gall midge has been seen with its long ovipositor (which 

 is longer than the rest of its body) inserted in the side of the 

 blossom before it opened, and generally it lays its eggs in the 

 middle of one or more blossoms by piercing the petals. Before 

 the blossom is expanded the larva? descend to the core, remain- 

 ing there until the inside is exhausted. They generally leave at 

 a rainy time, coming out to the exterior by cracks or by boring, 

 from whence they spring to the ground, but ofttimes remaining till 

 the fruit falls." Mr. Whitehead says : " The female fly is about 

 one-twelth part of an inch in length, and places its eggs in the 

 flower part of the fruit just as it sets, or before setting. The 

 larvae from these follow the pistils into the ovary, feeding upon 

 the tiny fruitlets, and may be found burrowing into the flesh. 

 After a while they work through the calyx or some crack 



