ORDER HYMENOPTERA 227 



ton, New Brunswick, the larvae are still in the leaves in 

 early October. That the beginning and end of the genera- 

 tions is not sharply marked is apparent from the fact that 

 larvae of different sizes are present in the leaves at the same 

 time. 



Fig. 69. Mines of Metallus rubi on blackberry. (Drawn by John D. 

 Tothill.) 



The eggs according to C. R. Crosby are usually placed 

 near a prominent vein. They are to be found in blisters 

 about 0.75 mm. in diameter. The eggs are nearly white, 

 smooth, and somewhat flattened between the cuticles. 

 The cavity previously occupied by these eggs can often be 

 distinguished at the border of the mine. 



