8 NEW ZEALAND ENTOMOLOGY. 



Order VII— HEMIPTERA. 



Wings four, in some cases wholly membranous, but in 

 a large proportion of the families the basal portions of the 

 anterior pair are horny, and form protective cases for the 

 other pair when not in use ; mouth suctorial, consisting of 

 an elongate rostrum, enclosing four fine setae. The larva 

 and pupa resemble the imago, the latter being active, with 

 rudimentary wings. In a few instances, a slight divergence 

 from the parent form is shown in the preparatory states 

 (Cicadas, &c). This is a small Order, containing the 

 Cicadas or " Singers," Bugs, Plant Lice, and all the suc- 

 torial animal lice. (Plate XX.) 



After the Orders, the divisions to be considered are the 

 Groups, Families, Genera and Species. 



Groups are large divisions immediately subordinate to 

 the orders, and consist of a number of kindred families. 

 They are of great assistance to the student in dealing with 

 the very large Orders, such, for instance, as the Coleoptera. 



Families, again, consist of a number of allied genera, and 

 Genera, in the same way, of allied species. 



With regard to the Families, I have in the main followed 

 those of Professor Westwood in his ' Modern Classification 

 of Insects/ as most recent writers appear very much 

 divided in opinion as to the correct limits of these divi- 

 sions. Much diversity also prevails with respect to the 

 proper definitions of Genera and even Species, but I have 

 deemed it best to follow the authority of the latest cata- 

 logues in this matter, as any changes in nomenclature are 

 always liable to produce confusion. 



