64 PEAR. [1900 



mischief within — 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 

 inside. 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 larvte make oval cocoons of silk 

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

 early spring." There appears to be a difi'erence of date of time of the 

 maggots forming cocoons, and turning to pupal or chrysalis state 

 within 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.'''- 



The Pear Gnat Midge {D. pi/rii-om) is a very small two- winged, 

 gnat-like tiy, about the twelfth of an inch, or rather more, in length 

 (see figure, and lines giving natural length, p. 63), of a general greyish 

 or black colour ; but when looked at more in detail, the head will be 

 seen to be black, with a tuft of yellow hairs, and the body between the 

 wings also black, but with some grey markings and varieties of tint, 

 according to the direction in which it is looked at. The two wings are 

 dusky, clothed and deeply fringed on the hind margins with black 

 hairs, and with a tuft of yellow hairs at the root of each wing. 

 Abdomen dark brown, with long whitish hairs ; legs also brown, and 

 also clothed with white hairs, chiedy on the upper surface.! 



To save some amount of trouble to readers, I have preceded the 

 following communications, in each case, with a few lines regarding 

 the most important points of the observations. 



On Dec. 13th Mr. Geo. Brown, in reply to my enquiry as to amount 

 of prevalence of the Pear Gnat Midge in the gardens of the Marquess 

 of Lansdowne at Bowood, Calne, Wilts, was good enough to send me 

 the following satisfactory report, for which I am greatly obliged, as I 

 was aware that preventive treatment of the infestation had been carried 

 on there for the past two or three seasons under Mr. Brown's own 

 skilled superintendence. 



It will be seen that much good has been effected by tmichiuc/ under 

 the infested trees, and also by hand-picking. Mr. Geo. Brown's 

 communication was as follows : — 



" I am very pleased to be able to give you a favourable report on 



* For much useful information on this attack, see " The Pear Midge (Diplosis 

 pyrironi, Kiley)," Bulletin 99 of New Jersey Agricultural College Experimental 

 Station, April 4th, 1894. 



f For full description of the imayo, or Gnat Midge, of D. pyrivora, see paper 

 on this insect by R. H. Meade in ' Entomologist." vol. xxi. 



