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INTERNATIONAL CONGRESS OF VITICULTURE 



left to the specialist. However, the life histories of the several species are 

 similar so the remedial measures given for F. viticida will answer for the 

 control of the other species. The weakening of the vines is the most usual 

 effect of root-worm injury and while this may not always lead to the destruc- 

 tion of the vines, nevertheless they may be so weakened as to produce grapes 

 at a loss. 



During periods of severe infestation many vines are killed, sometimes 

 whole vineyards being practically destroyed, but this effect is limited to times 

 of greatest abundance of the insects and is only the exceptional effect during 

 ordinary years. 



Fig. 3. Adult (enlarged four times). 

 Eggs (enlarged four times). 



Fig. 4. (a) Larva (enlarged six times), 

 (b) Pupa (slightly enlarged). 



