i: 



The Origin and Affinities of 



the Dermaptera and Orthoptera of 



Western North America 



James A. G. Rehn 



Academy of Natural Sciences of Philadelphia, 



Pennsylvania 



r or the greater part of a half century the 

 assembly of data and evidence bearing on the fields of this symposi- 

 um, as relating to the Dermaptera and Orthoptera of North America 

 as a whole, has been a major objective of a group of colleagues now 

 or formerly associated with my institution. The evidence here 

 summarized has been drawn largely — and particularly for the 

 United States — from field investigations personally carried on over 

 a period of fifty-five years. 



Much of the past literature, and considerable past collecting, is 

 not at all helpful. However, very definite and clear-cut conclusions 

 are now emerging, as extensive collections, representing many 

 seasons of fully documented field work, are being critically studied 

 as part of a long-range project assisted by a National Science 

 Foundation grant. The general results, systematic, zoogeographic, 

 and binomic, are now being made known in a series of papers 

 preliminary to a more condensed monograph. In view of these 

 circumstances citations to the literature have been omitted in this 

 paper. 



In the present analysis of the subject I am assuming a full under- 

 standing of the terminologies that have long been in general use 

 for life areas, particularly by the vertebrate school, which in North 

 America produced some of the zoological pioneers in biogeography ; 

 also that the descriptive terms, based on physiographic areas, such 

 as Cordilleran (for the Rockies alone), Sierran, and Campestran, 

 are equally familiar and precise. 



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