Allantm scalaris. 



CHAPTER XI. 

 HYMENOPTERA. 



AMONGST the Neuroptera we have seen several groups 

 of insects agreeing pretty closely in many respects, 

 but differing remarkably in the character of their 

 metamorphosis; amongst the Hymenoptera, on the 

 contrary, the metamorphosis is equally complete 

 throughout ; but the parts of the mouth which, in the 

 earlier groups, present all the ordinary characters of 

 the mandibulate structure, gradually change their 

 form, until we find that only the mandibles retain 

 the power of biting, the other organs becoming con- 

 verted into a regular suctorial apparatus. The exist- 

 ence of strong horny mandibles, however, always 

 shows these insects to belong to the mandibulate or 

 biting section of the insect world. 



