THE STRUCTURE OF INSECTS. 3 



down on the side and merging into the pleurum without 

 any suture or seam. The pleurum is indicated by the row 

 of spiracles, which will be noticed farther on. The sternum 



Tarsus 



FIG. 1. -External anatomy of Caloptfnus spretus, the head and thorax 

 disjointed. Kingsley del. 



