CALIFORNIA ACADEMY OF SCIENCES. 283 NEW GENERA AND SPECIES OF CALIFORNIAN COLEOPTERA. BY THOS. L. CASEY, LT. ENG'RS. Read November 16th, 1885. As a member of an expedition which explored several of the northern counties of California during the past summer, opportunity was given me to collect a considerable number of specimens of Coleoptera. Among these several are thought to be of sufficient importance for description in an isolated manner, and the present occasion is also taken to interpolate a few from other portions of the state. The present paper is published with the hope that they may not prove entirely uninteresting to specialists in the several families. It will be observed that by far the greater number of species here brought to notice, belong to the great tribe Aleocharini of the Staphylinida?; these are all assignable, however, to genera containing but a comparatively small number of species, and in which no confusion can be made by the description of special forms. The great genera Hom-alota, Aleochara, etc., are left for the future consideration of others who must be more experienced in the study of them than the author, and with the hope that this much needed revision will soon be undertaken; the group merits all the attention which can be bestowed upon it, and contains some of the most interesting and elegant forms of the entire family. The genus here described under the name Colusa, appears to have been entirely overlooked, although the species are very striking in appearance and are compara-tively abundant; they live in wet moss at the bottom of ravines in the coast regions of the state. The genus ap-pears to be quite local, and Dr. Sharp has recently described several closely allied genera from various regions of Mexico and Central America. 8— Issued December 15, 1885.