THE FRIT FLY. 43 



PREVENTIVE AND REMEDIAL MEASURES. 



Wherever an infestation has been experienced, onions should not 

 be grown on the same ground the following year. The soil should also 

 be deeply ploughed or trenched, and an application of Apterite given. 



The remedies which have been recommended from time to time 

 are very numerous, but mostly ineffective ; amongst these may be men- 

 tioned watering the rows with paraffin oil and water, soap-suds, house- 

 slops, and liquid manure ; dusting with gas-lime, soot, charcoal dust, etc. 



THE FRIT FLY. 



Oscinus frit, Linn. 



In the Midland counties, and generally throughout the country, the 

 larvae of this small fly have been particularly plentiful ; and oats and 

 barley have suffered to a considerable extent. 



LIFE- HISTORY. 



The flies appear from April to May, the females depositing their 

 eggs on the leaves of the young plants. On hatching, the larva 

 which is a small, fleshy, legless maggot makes its way to the lower 

 part of the plant, and thence into the centre of the stem, subsequently 

 pupating there. About the middle of July the second brood of flies 

 appears ; and the females lay their eggs on various grasses, and, if 

 sufficiently developed, in the ears of oats and barley. 



The third brood of flies appears in August or September, the 

 females depositing their eggs on different wild grasses, and the flies 

 from this generation issuing from the puparia in the following spring. 



PREVENTIVE AND REMEDIAL MEASURES. 



The importance of early sowing will at once be fully recognised, 

 and the advantage of a dressing of artificials to stimulate growth. 



Wherever an attack has been noticed the previous season, the 

 land should be ploughed with a skim-coulter attached ; or deep 

 ploughing resorted to. 



Oats and barley should be planted the next season as far away 

 as possible from areas previously affected. 



All wild grasses should be destroyed. 



THE CARROT RUST FLY. 



Psila rosae (Fabr.). 



The last bad attack we had of this fly in the Midlands was in 1902 

 and 1903, since, I have had few cases until the past season, during 

 which they have been somewhat numerous. 



