vi. PREFACE. 



over the regions adjacent to the Rocky mountains, while 

 diligent collecting in other parts of the country has been 

 attended with such success, that but few of the species known 

 to him are wanting in my collection. The entire destruc- 

 tion of his original specimens would be the subject of much 

 greater regret, were it not for the fact that his descriptions 

 are so clear as to leave scarcely a doubt regarding the object 

 designated. I am thus enabled to assign to nearly all of 

 his Coleoptera their proper place in the modern system. 



Such of the original plates illustrating the American En- 

 tomology as remain, have been purchased for the present 

 work : unfortunately plates 37 — 54 have been destroyed ; 

 these have been re-engraved by Mr. John Gavit, of Albany, 

 which will be a sufficient guarantee of their being exact 

 copies. The plates of Coleoptera have been recolored from 

 specimens, and will be found more correct than those in the 

 original work. 



Typographical errors in the original memoirs have been 

 corrected ; other errors have not been changed, or if noted, 

 the corrections have been placed in brackets. 



To add interest to the work, Mr. Ord, late President 

 of the Academy of Natural Sciences of Philadelphia, has 

 kindly permitted me to use the heretofore unpublished 

 memoir of Mr. Say, written by him, and read before the 

 American Philosophical Society. The long and unbroken 

 intimacy existing between these two men of science, renders 

 this production of peculiar value, and leads us, by a know- 

 ledge of the difficulties with which they contended, to esti- 

 mate still more highly the labors of those who have in the 

 early history of science in America prepared the way for 

 students who now labor, not with more skill, but with greater 

 facilities. 



John L. Le Conte. 



Philadelphia, May 1st, 1859 



