COLEOPTEBOUS INSECTS. 99 



there are three obvious divisions, consisting of the 

 head, thorax, and abdomen. 



The head appears as a single piece, without any 

 obvious suture or division, and is generally of a 

 harder substance than the rest of the body. Its 

 form is most commonly triangular with the angles 

 somewhat rounded, frequently it is orbicular, and 

 in a numerous and important tribe (Curculionid<e) 

 it is produced into an elongated rostrum or snout. 

 The hinder part is occasionally constricted into a 

 short neck, which inosculates in the anterior cavity 

 of the thorax, and admits of a considerable degree 

 of motion in almost every direction. The position 

 of the head, or its inclination with respect to the 

 body, is generally somewhat slanting, forming an 

 angle more or less obtuse ; but in some instances it 

 is bent inwards and forms an acute angle. The 

 anterior part of the head is occupied by the mcuth 

 and its various appendages, near to which are placed 

 the antennae and eyes. 



The mouth is greatly more complicated in its 

 structure than among the higher animals, and its 

 various parts undergo numerous modifications in 

 different tribes. They will be found however to be 

 essentially as follows : the labrum or upper lip, the 

 mandibles, the maxilla or under jaws, the labium 

 or under lip, and the mentum. 



The upper lip (labrum) is a small moveable piece 

 placed on the upper side of the mouth, and closing 

 it from above. It is variable in form, but is most 



