HEXAPODA : DIGESTIVE SYSTEM. 



291 



a single joint ; and this joint or part is often subdivided 

 into three parts, each ending in a sort of tooth for the 



FIG. 3f,l. 



Digestive Apparatus of an Insect Beetle Magnified. 



a, head, jaws, etc. ; 6, oesophagus ; c, crop ; d, gizzard ; e, chylific stomach ; 

 /, biliary vessels ; g, intestine ; h, secreting organs ; t, vent. 



purpose of cutting food. The cutting edges are opposed 

 to each other, or overlap, and their motion is horizontal 



