208 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



and fall to the ground. The larvae generally go into the 

 ground about the middle of June, varying with the season. 

 They pupate after a while and remain till the spring following, 

 there being, happily, but one generation. It would seem the 

 only remedy is to pick off the infested Pears, which may easily 

 be seen, before the larvae have escaped, and destroy them. The 

 larva is yellowish, about one-twelfth of an inch long, and has 

 the power of skipping. The fly is dark grey or blackish. The 

 larva burrows into the ground about an inch, and soot, lime, or 

 other caustic and offensive substance is recommended to be forked 

 in around the tree." Such is a lucid description of the history, 

 but how to successfully combat such a minute insect in one of 

 his favourable seasons is a problem I have not yet been able to 

 solve. This season I have counted as many as twenty-seven of the 

 yellowish maggots inside a single young fruit, and every one of 

 the pears on well-set trees has contained one or more maggots, 

 thus causing the entire loss of the crop. Marie Louise seems a 

 favourite sort for this pest's attack. At first the tiny Pears do 

 not show signs of the fatal injury, but, as swelling progresses, 

 the little fruits become deformed or irregular in shape, their 

 colour changes to sickly yellow, and ultimately they drop off 

 wholesale. We were badly attacked by the " Diplosis " in the 

 spring of 1892, so much so that we resolved to make a vigorous 

 onslaught on him. All the fallen Pears, and those infested on 

 the trees, were collected and burnt, and to make sure, as we 

 thought, in the early autumn we scraped off all the loose soil to 

 the depth of two inches and beyond the diameter of the branches, 

 wheeling it right away, and replacing with fresh loam. We 

 served all the garden trees thus, and hoped to have entirely 

 cleared out the chrysalids then dormant. But, behold, after all 

 this trouble, how great was our disappointment to discover in 

 the following spring we seemed to be even worse attacked than 

 before ! We can only surmise that adult insects came on the 

 wing from other trees in the neighbourhood, which only adds to 

 our perplexity — how to prevent future attacks. The only remedy 

 we can imagine will be to syringe the trees daily with some 

 form of mild, but not volatile, insecticide ; probably soft soap 

 and quassia would be sufficient. This would require to be done 

 from the time the flower-buds were just visible until the flowers 

 open, when it must cease for the obvious reasons of setting. 



