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Show 66 MR. C. TATE REGAN ON [May 12, about 2* times. Snout, including processes, 1| times as long as eye, the diameter of which is 4 times in the length of head, interorbital width 4| times. Interorbital space concave; no spines on snout. Anterior processes longer than broad, flat, rounded, with denticulated edges; from each a ridge running backwards, ending in a rather broad, flat, somewhat obtuse prseopercular spine; a short ridge below eye, without spine ; a short feeble spine above posterior part of eye, a stronger one behind it near posterior margin of head, below which another, somewhat weaker; operculum with well-developed spine. Margin of lower jaw with groups of short tentacles and a pair of longer fringed tentacles which extend back scarcely beyond the cleft of mouth. Gill-rakers moderate, about 16 on lower part of anterior arch. 27 scutes in 4 longitudinal series, the 3 upper series with strong recurved spines, the spines of the lower series quite rudimentary. D VIII, 17, the spines slender, the third longest and equal to f- the length of head, thence decreasing; soft rays increasing in length to about the sixth, which is as long as the longest spine, thence decreasing. A I 16, about £ the height of dorsal; pectoral half as long as head ; ventrals extending to anal; caudal emarginate. Greyish (in spirit); pectorals dark. Description based on two examples from Rio Janeiro, the larger 190 m m . in total length. This species is very distinct from others so far described, and it is difficult to say which should be considered its nearest ally. CARANGIDjE. The American species of the genus Scombroides Lacep. {Chori-nemus Cuv. & Val.) belong to the section Oligoplites Gill, distinguished by having 4-5 dorsal spines, no pterygoid teeth, cheeks with sclerous plates attached to the suborbitals, and linear scales. There has been considerable difference of opinion as to the number of species which ought to be recognised. Three examples of S. saliens Bloch from Rio Janeiro agree in every particular with others in the British Museum Collection from the Pacific Coast of Mexico and Ecuador. This species is readily distinguished by the anterior dorsal with 4 spines, the deep body (depth 2f-3 times in total length), and the wide mouth (the maxillary extending well beyond the eye). S. palometa Cuv. & Val., hitherto regarded as a variety or subspecies of S. saliens, is really quite distinct, the depth of the body being contained about 3 § times in the total length and the maxillary only extending to below the posterior margin of the eye, or a little beyond. This species has hitherto been recorded only from the fresh or brackish waters of Lake Maracaibo, Venezuela, but the British Museum Collection contains a small example from Lake Yzabal, a large inland lake communicating by the Rio Dulche with the Bay of Honduras. _ S. alius Giinther and S. saurus Bl. Schn. each has five spines in the anterior dorsal; in the former the body is deep, |