42 REPORT ON INJURIOUS INSECTS FOR 1907. 



differ. I think there is very little doubt as to its being specifically 

 distinct from that species. 



THE WILLOW MIDGE. 



Cecidomyia rosaria, Liv. 



The rose-shaped galls formed by the larvae of this tiny midge 

 have been received on various species of willow. 



It has been particularly prevalent during the past year ; but it 

 can scarcely be described as a pest, as the damage is extremely small. 



THE PEAR MIDGE. 



Diplosis pyrivora, Riley. 



For the first time for many years I am able to record a diminution 

 of this pest in many orchards where hitherto it has been very plentiful. 

 This improvement has been brought about entirely by burying the 

 surface soil. 



During the year I have made a number of experiments on the 

 larvae and pupae. 



In June last Mr. J. Lees sent me, from Kent, some larvae and 

 pupae which were dipped in the Vi Fluid, i in 100, the larvae were 

 killed in about fifteen minutes, and the pupae in about thirty-five. 

 Mr. Lees suggested, as a result of this experiment, that possibly it 

 might be worth while saturating the ground, say about the end of 

 May, beneath affected trees. 



A second experiment with Apterite points to a more practical 

 remedy, however ; full particulars of which I hope to give in a later 

 Report. 



THE ONION FLY. 



Phorbia cepanun, Bouche. 



Although I have had only a single case of this pest reported by 

 correspondents during the past year, two of my Voluntary Observers 

 have sent in long accounts of the mischief done in Warwickshire and 

 Staffordshire. 



LlFE-HlSTORY. 



The female fly deposits her eggs on the young leaves of the Onion, 

 close to the earth. The larvae hatch out in a few days, and make their 

 way into the base of the bulb, where they feed for two or three weeks. 

 Miss Ormerod states a fortnight, but I have notes of a case where the 

 larvae were in the bulbs for nearly a month. They then pass out of the 

 bulb into the soil, and there change into pupae, from which the flies 

 issue in about fourteen days, and again attack the plants which had 

 previously escaped. Given favourable weather, and the requisite food 

 plant, there may be three or four broods. 



