106 NATURAL HISTOET OF 



e c 



Fig. 2. 



The next part of a coleopterous insect which re- 

 quires some notice is the thorax, which it will suf- 

 fice for our present purpose to describe as a single 

 principal portion, intermediate between the head 

 and abdomen. It is the seat of all the organs of 

 motion, and is usually strong and muscular, as it 

 forms the chief support of all the other parts of the 

 body. It is generally wider than the head and nar- 

 rower than the abdomen. The form of the upper 

 and exposed portion is very variable : in an exten- 

 sive tribe of beetles it is more or less heart-shaped, 



