Since the reprint of Kirby's Fauna Boreali-Americana began, much has been learned concerning the species of Coleoptera therein described or mentioned, so that at the present time very few remain unidentified. Through the kindness of the authorities of the British Museum. every facility was granted to Mr. Leconte and myself for the study of Kirby's types, and the results of these studies have already been made known by Dr. Leconte. It will be noticed in very many places that the synonymy here given differs very greatly from that given by Mr. Bethune, who compiled from the best known sources all that was at the time known or guessed concerning Kirby's species.