114 ELEMENTARY LESSONS ON INSECTS 



7. Spiracles at the front margin of each segment of the 

 synthorax and of the first seven segments of the abdo- 

 men. 



8. The absence of wings externally. 



9. The prolegs underneath the abdomen, their number 

 and position, and the circlet of crochets on the end 

 of each. 



10. The vestiture of bristles on the body. 



