218 



DIPTEPvA OR TRUE FLIES. 



109, 4), a yellowish grub with two black points at tlie end of the 

 tail. One often finds these grubs abundant in rank manure. 



Prevention and Treatment. — Little can be done when the grubs 

 are once installed in a plant. Where cabbages are grown year 

 after year on the same land, the soil is sure to become contam- 



Fig. 100, — Root-eating Flies. 



1, Larva of An.llwmyia lyrassicm ; 2 and 3, pupariuni of A. hra^ica ; 4 and 5, A. radi- 

 cum; (3 and 7, larv^ of llomalomyia ; 8 and 9, HoniaJomyia sp. (?) (Curtis.) 



inated unless cleaned annually ; for this gas lime is recom- 

 mended. Dibbling in the plants with a little soot and lime is a 

 good deterrent ; and broadcasting the same over j'oung plants 

 not only keeps off these flies but slugs as well. All the diseased 

 cabbage stalks and roots ought to be biu'nt, instead of being put 

 up in heaps to rot, when many of the grubs will escape. 



Wheat-bulb Fly (Hylemyia coarctata). 



The Wheat-bulb Fly is chiefly harmful in the Fen districts 

 to wheat. It is said to be most destructive on land fallowed in 

 tlie previous summer, and where the crop has been so thin as to 

 expose the land (Ormerod). The Wheat-bulb Fly lays her eggs 

 in the young wheat, the larva living in the centre of the plant. 

 The grub is white in colour, and can be told by the curious pro- 

 cesses at the tail end. These larvne are found in April destroy- 



