94 PEAR. [1899 



At this stage — that is, when the young Pear is destroyed by the 

 mischief witliin — the fruit usually cracks or falls to the ground, and 

 the maggots leave the fruit by way of the open cracks if it remains on 

 the tree, or, if it falls without cracking, may remain for some weeks 

 witliiu. In either case they bury themselves in the ground, and 

 (quoting from Prof. J. B. Smith ; for reference, see note below) go 

 down to a depth *' varying somewhat with the condition of the soil, 

 from one-half to two inches, and there they lie for some time un- 

 changed. About midsummer the larvie make oval cocoons of silk 

 covered with grains of sand, and in these they lie unchanged until 

 early spring." There appears to be a diflference of date of time of the 

 maggots forming cocoons, and turning to pupal or chrysalis state 

 witliin them, possibly from not being in quite natural circumstances ; 

 but in regular course, whatever the exact date of pupation may be, 

 the Gnat Midges come out of the ground in spring ready to attack the 

 blossom-buds of the Pear.* 



On the above points in the life-history — that is, in the circumstance 

 of the maggots falling to the ground from or in the fruit, and burying 

 themselves a very little beneath the surface, where they go through 

 their changes to the perfect Gnat- fly — the preventive measures almost 

 entirely turn. 



These mostly consist in gathering the injured fruit before the 

 maggots are arrived at the stage at which they leave it, and ilestroijimj 

 maggots and little Pears together; also of skimming the surface of 

 the soil beneath infested trees and removing it, and burying it down or 

 otherwise destroying it, so that the maggots within may be certainly 

 destroyed ; or dressing the surface with some application (preferably 

 with kainite) which has been found serviceable in preventing develop- 

 ment of the maggots. 



Practical notes of the effect of this, and of some other points of 

 treatment will be found in the following observations, and are given 

 in the successive order in which requests for information, with speci- 

 mens of the Pear Midge maggot accompanying, were sent me in 1898, 

 thus (taken together with the reports of 1899, appended seriatim) 

 affording a usefully interesting view of the effect of such preventive 

 measures as were carried out. 



On May 13th, 1898 (the earliest date of enquiry as to attack then 

 in active stage sent me), I received the following enquiry from Mr. H. 

 H. Williams, of Pencalenick, Truro, Cornwall : — 



"Could you kindly tell me if it is possible to prevent the attacks 

 of the insect which has got into the young Pears I enclose ? Last 



* See, for much useful information on this attack, " The Pear Midge {Dijilosis 

 pyrivora, Biley)," Bulletin 99 of New Jersey Agricultural College Experimental 

 Station, April 4th, 1894. 



