IV PREFACE. 



Pyrochroidce, Anthicidce, Melandryidce, Mordellidce, Stylopidce, 

 Meloidce, Cephaloidce, (Edemeridce, Mycteridce, Pythidce, Cur- 

 culionidce, Scolytidce, and Anthribidce, Brenthidce being the 

 last. 



The author should here state, in justice to himself, that the 

 primary object in preparing the systematic portion of the 

 work was to give as clear a view as possible of the larger 

 groups of insects ; so that the groupings of the families into 

 subdivisions of suborders have been omitted for the sake of 

 perspicuity. Thus, the difference between the Heteropterous 

 and Hemipterous divisions of the Hemiptera is not perhaps so 

 clearly indicated as may seem desirable ; so also, the difference 

 of the Tenthredinidae and Uroceridae from the rest of the 

 Efymenoptera, of the Lice from the rest of the Hemiptera, or 

 the Lepismatidae, Campodese and Poduridse, from the remainder 

 of the Neuroptera. Perhaps in endeavoring to bring out 

 clearly the essential unity of organization in the members of 

 the larger groups, sufficient justice has not been paid to the 

 frequent diversity observable. Certain small and unimportant 

 families have also been omitted ; it is believed, without detri- 

 ment to a work of this scope. 



Most authors regard the Hymenoptera and equivalent 

 groups as "orders" rather than "suborders." When the 

 reader prefers, he might alter to suit his views. It is not 

 improbable that the Hexapoda, Arachnida and Myriopoda are 

 subclasses ; hence, the Hymenoptera, etc., may be considered 

 as orders, and then, for example, the Hemiptera, Heteroptera 

 and Lice (Pediculina and Mallophaga) might be regarded as 

 suborders of the grand group Hemiptera. It matters little to 

 the author, so long as the fact (or what he believes to be the 

 fact) be recognized, that the Hexapods, Arachnids and Myrio- 

 pods are subdivisions of a class, and not separate classes 

 equivalent each to the Crustacea, for example. 



Salem, April, 1874. 



