178 



GARDEN FOES. 



liddling the steins and leavers with holes and destroying 

 the plants. They do most harm on light soils and in dry 

 seasons. When very numerous they will destroy the 

 whole crop in a few days. 



Remedies. — The chief point to bear in mind is to encou- 

 rage the seedlings to make vigorous growth from the first. 

 This can be accomplished by the use of the artificial 

 manures advised for turnips. The beetles will not inter- 

 fere with the seedlings after they have formed their rough 

 leaves. Other remedies are to fix some tarred sacks or 

 sheets to a roller and then draw this over the ground. 



TUHNir LEAF-MINER (PHYTOMYZA NIGUICORNI.-). 



Fig. 7. Under side of turnip leaf mined by the larva^ of tiie fly (Fig. 8, largely 

 iiiagnitied) ; 7, Pupa in the Vaf; &, Nat. size of fly. 



This will pick up a very large number of the beetles. Dust- 

 ing the plants with lime or soot early in the morning 

 whilst the seedlings are moist willi dew is a good remedy. 

 Weeds, such as charlock, etc., should not be allowed to 

 grow in the fields, as these form a luu'bour for the beetles. 



Turnip-leaf Miners (Drosophilia flava and Phyto- 

 myza nigricoi*nis) are the grubs of two flies which feed 

 upon the soft tissues of the leaves of the turnip. The 

 Drosophilia is about one-tenth of an inch long, of a yellow 

 colour, while its larvae are green, and live beneath the skin 

 on the iii)per sides of the leaves. The Phytomyza is also 



