FIG. 75. EXTERNAL FEATURES OF A DISARTICULATED BEETLE 

 A STUDY OF AN Exo SKELETON. 



The head (PI) consists of six or seven fused segments, surrounded by 

 coalesced chitinous plates. It bears the compound eyes (E), the pre-oral 

 antennae (A), and, beside the mouth, the strong biting mandibles (M\ '), 

 the first maxillae (MX), and the second maxillae which fuse to form the 

 labiuin (I,). 



The second great division of the body is the thorax, \yhich consists of 

 three segments, each with a pair of walking legs. First is the prothqrax 

 (PR) ; then the mesothorax (MS) with the first pair of wings turned into 

 heavy wing-covers or elytra ; then the metathorax (MT) with the second 

 pair of wings which strike the air in flight. 



The parts of an insect's leg are shown, the coxa(C), the minute 

 trochanter(TJJ), the femur (F), the tibia (77), the tarsus (TA, with four 

 or five joints, the last of which bears the claws (CJ .). 



The third great division of the body is called the abdomen ; it has seven 

 or eight segments, but no appendages. 



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