- - ' ^ I 



APR29 ]91f 



ANNALS 



OF 



The Entomological Society of America 



Volume XII MARCH, 19 19 Number 1 



THE DISTRIBUTION OF INSECTS IN WESTERN 



NORTH AMERICA.* 



By Edwin C. Van Dyke, 



University of California, Berkeley, Cal. 



The fauna of the western part of North America has long 

 been recognized as possessing many characteristics which have 

 differentiated it from that found elsewhere in North America. 

 This is particularly the case as regards the insects and Le Contef 

 as early as 1859 called attention to this. Other entomologists 

 in more recent years have mentioned this fact and have cited 

 many cases to show its peculiarity. The insect fauna as a 

 whole, however, has not been studied in regard to this point, 

 in the manner that it has merited. 



Many years ago, I became interested in the subject and 

 I have kept up my interest ever since and have availed myself of 

 all opportunities that would enable me to gain information 

 bearing upon it. I have studied all orders of insects to a certain 

 extent, but most of my conclusions have been based upon a 

 close study of the Coleoptera, particularly of the win^ :ss and 

 less mobile groups, such as certain of the CarabidcB, the Silphidce, 

 the Tenebrionidce, the Otiorychince, and so forth. The other 

 Coleoptera were used as checks as were in fact other groups of 

 insects, and all other information bearing upon the subject of 

 distribution in the territory under. study, freely drawn upon 

 for purposes of guidance. 



* A revision of the paper read August 5, 1915, at the University of California^ 

 before the Summer Meeting of the Entomological Society of America. 



t The Coleoptera of Kansas and Eastern New Mexico, by John L. LeConte, 

 M. D., Smith. Miss. Contrib. to Knowledge, Vol. XI (1859). 



