Insects Injurious to the Rasj^h 



erry. 



439 



THE RASPBERRY GALL FLY. 



{Lasio])tcra ruhi. Schrk.) 



This fly is one of the gall midges or Cecidomyidm. It has seldom 

 been brought to my notice as occurring in any amount on raspberries 

 (1), and can scarcely be looked upon as a pest. It frequently may be 

 met with on brambles in hedgerows. 



Ormerod (2) refers to what is evidently this insect. Specimens 

 were sent her from Kent by 

 W. C. Whitehead in 1884. 



The galls contain eight to 

 ten orange coloured larvte in 

 the black, rotten interior. The 

 galls are situated on all parts 

 of the cane ; the largest measure 

 1 inch across and have thick 

 walls. The damage noticed in 

 1898 was very apparent, several 

 attacked canes showed very few 

 leaves and no fruit. It was 

 observed on brambles in the 

 neighbourhood in small num- 

 bers. The larva3 are full grown 

 by April and are briglit orange 

 in colour. Length -^^ inch. 

 They pupate in the galls by 

 the first week in May. The 

 flies hatch out in June, and 

 some at the end of May. The 

 female lays eight to twelve eggs 

 at the base of the buds and side shoots during June. These hatch 

 in eight days. 



The young larvas burrow into the rind, and by six weeks a distinct 

 gall is formed and in these the larvie remain and pupate in the spring, 

 from March to May. The galls are closed, the flies escaping from 

 cracks or decayed parts. All galls when first seen should be cut off 

 and burned, as this fly has been increasing materially in Kent during 

 the last few years. 



Kaltenbach considered the flies reared from such galls by himself 

 to be Lasioptcra arfjijrostictar, Meigen. But this species is the same 

 as L. ruhi. 



[W. U. Hammond. 

 FIG. 287.— GALLS OF Lasioptera ruhi. 



