EXTERNAL ANATOMY. 



27 



[Fig. 3.) 



Diaj^TJim illustrating tin' slnictunil jiaits of a beetle. 



or breast-plate, and is divided into three parts, the 2>rosfernum or fore 

 breast-plate ; the mesosternum or middle breast-plate ; and the mefaster- 

 num or hind breast-plate. Each of these parts has a side piece, called 

 the episternum ; so that there is an epi stern nni of the prothorax ; an 

 episternani of the niesothorax ; and an epistei'nnni of the metathorax ; 

 all of which are labeled in the iignre. Directly behind each episternum 

 is a smaller piece called the cpimeron. These are indicated in the figure 

 by stars ; three stars marking the epimeron of the i)rothorax ; two stars 

 the epimerou of the mesothorax ; and one star the epimeron of the meta- 



