The following study is based on the types of LeConte and Horn and material from the American Museum, Museum of Comparative Zooslogy, Canadian National Collectioas and from the collections of Messrs. Owen Bryant, C. A. Frost, Ralph Hopping, W. Knaus, and J. B. Wallis. Dr. W. Horn supplied specimens of two European species, of Aegialia rufa Fab. and sabuleti Panz.; these were of much aid in the study of the subgenera, the descriptions of which were made as detailed as possible so that descriptions of the species could be shorter.