THE GOOSEBERRY SAW-FLY 



97 



cocoon in a curved position, the head and tail being bent 

 round to the ventral side. If disturbed, it is capable of 

 sluggish movement. In Lepidoptera the resting 

 larva is a brief and unimportant stage, while 

 the pupal stage is often prolonged. In saw- 

 flies the resting- stage is often prolonged, and 

 the pupal stage shortened in proportion. 



Within the body of the resting larva the 

 destruction of old parts and the development 

 of new go on with great rapidity. When the 

 imaginal organs are well advanced the last 

 larval skin is cast, and the pupa appears. It 

 bears a general resemblance to a Lepidopterous 

 pupa, but the appendages are not glued down, 

 there is no proboscis (for the imago has a biting 

 mouth), and peculiar organs, the saws, appear 

 on the ventral surface of the last abdominal 

 segments of the female. As in all pupae, the p.. g _p^ ^ 



body is com- of gooseberry 



pletely in- =='"'"J-- "" '■ 

 vested by a special pupa- 

 skin. 



When the fly is ready 

 for active life it creeps 

 out of the ground, and 

 hovers round the bushes 

 on which it was reared. 

 It is sluggish, and does 

 not usually fly far. Hence 

 one garden may be de- 

 vastated with saw - flies, 

 while another, at no great 

 distance, is free. The 

 fertilised female lays her 

 eggs on several different 

 leaves, and then dies. The 

 fly has four large mem- 

 branous wings and biting 

 mouth-parts, as in other 

 Hymenoptera. The long feelers are nine-jointed. The narrow 

 waist, distinctive of such Hymenopterous flies as sting or 



G 



Fig. 59. — Gooseberry saw-fly, 

 ventral surface, X 5. 



