INSECT INTRUDERS. 





female has a sharp pointed instrument at 

 the end of her body, and by means of this 

 she cuts two rows of parallel diagonal in- 

 cisions down the long green shoots of the 

 rose bush as shown here and places an egg 

 in each. These incisions may number as 

 many as 6070. In other words, each 

 little fly lays as many as 60 70 eggs and 

 the great powers of increase possessed by 

 this insect are thus easily 

 accounted for. The tiny 

 grub possibly feeds for a 

 few hours in his little cradle 

 in the stem before he quits it 

 to devour the leaves in the 

 manner detailed below. 



After the young larvae 

 have left the cells, the 

 remains of the epidermis 

 over them peels off, the cells 

 shrink, and you see on the 

 stem a brown patch consist- 

 ing of an elongated elliptical 

 depression occupied by two 

 60 



