An OrtJiopterous Insect. 129 



AN ORTHOPTEROUS INSECT 

 (Acridium americanum}. 



ADULT STAGE. 



External Anatomy. Observe that the three divisions 

 of the body, head, thorax, and abdomen, are here much 

 more definitely outlined than they were in the caterpillar. 



The head bears a pair of antenna, each made up of sev- 

 eral joints ; a pair of large compound eyes ; a median and 

 two lateral ocelli; a bilobed lab rum or upper-lip; a pair 

 of strong mandibles or jaws which move laterally ; a pair of 

 maxilltz lying immediately behind the mandibles, and each 

 bearing a lateral, jointed apparatus, the palpus ; and a 

 bilobed lower-lip or labium, which lies posterior to the max- 

 illae, and is also provided with palpi. As the mouth-parts 

 are opened and the mouth exposed, the tongue will be 

 noticed as a chitinous papilla on its floor. 



The thorax has the same segments that were present in 

 the caterpillar. The prothorax is the largest of the three 

 and bears the first pair of legs. Its tergum or dorsal por- 

 tion is enlarged and forms a shield. The meso- and meta- 

 thorax are somewhat united together. The mesothorax 

 bears the second pair of legs and the first pair of wings, while 

 the metathorax bears the much larger third pair of legs and 

 second pair of wings. 



The legs will be found to consist of a series of joints and 

 to be terminated by a pair of hook-like organs. The joints 



