Height of pectoral fin less than length of head; its width about one-third of its height, middle rays longest. Dorsal arising above pectoral joint, its length one-third that of the fish; first spine one-ninth the length of the fin; the other spines lengthening to the commencement of the soft portion, of which the longest ray is one-fifth the length of the fin, and the last ray one-fifteenth; the entire fin having a gradually arching outline. Caudal moderately broad, deeply forked, and acutely pointed; the upper lobe slightly the largest. Anal similar in form to dorsal, arising opposite its eighth soft ray and prolonged a little farther back. It is three-fifths as long as dorsal, its height about one-fourth its length, the first (spinous) ray and the last each half as long as the longest. Ventrals four-fifths the height of pectorals, arising immediately behind them; their width one-third of their length. D. VII, 23-2, C 3-1-6-6-1-3, A I-2-21-2, P 6-1-11, V, I-1-1-3. Scales 175, 13/32-10/10. _Colors._—Pale silvery brown, white below; an obscure row of brown spots and mottlings on sides; fins and tail olive near base; iris dark brown and gilt. _Remarks._—This fish seems to be a very aberrant form of the Percoid family, having many of the characters of other orders. Its general form and dentition are those of some Sciaenoids, while its entire dorsal, opercular armature and only five branchiostegals separate it both from them and the Percoids. The very long anal is another character found in few if any members of these families. I can find nothing in the pharyngeal bones to indicate its affinities, these being closely like those of both the above families as shown in _Seriphus politus_ and _Paralabrax clathratus_, which on comparison have them almost exactly similar. The genus _Heterognathodon_, of Bleeker, has several of the most peculiar characters of this one; but not having a full description of it, I cannot compare them. There are generic differences at least, and the habitat is widely different, being the East Indies. Richardson places it with other aberrant genera in the family _Theraponidae_—(_Datninae_, of Swainson,) which is probably a mixture of several. The outline figure represents the fish one-third the natural size; 22 inches. This fish is caught rather plentifully in autumn at Catalina Island, where I obtained the one here described, in October, 1861. During my late visit there, in June and July, none would bite, and I have not yet obtained any duplicates. It is called by the very vague name of “White-fish.” The figure being made from a skin may be a little inaccurate in proportions; but I hope to be able to present a better one in the Report of the Geological Survey.