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Show 726 DR. A. G U N T H E R O N FISHES [June 6, length of the head, broad, with the upper profile descending in a gentle curve. Mouth wide, wider than the distance between the eyes, with the upper jaw overlapping the lower. Nasal barbels minute ; maxillary barbels extending to the margin of the prae-operculum; outer mandibulary barbels not reaching the gill-opening; inner mandibulary barbels anterior to the outer, and less than half a diameter of'the eye distant from each other. The vomerine Fig. 6. ^'v-'i'ri;/''•'•'•^ii.'iy-'^'.y f <\ i Chrysichthys lagoensis. teeth are disposed in a narrow band on each side, tapering behind, the two bands being separated in front by a toothless space, less than half a diameter in w idth ; however, on the right side there are vestiges of another narrow tooth-band, stretching across the junction of the vomer with the palatine.1 Each half of the intermaxillary band rounded at its lateral extremity, half as long as broad. Tbe width of the bony interorbital space is more than the diameter of the eye, which is two fifths of the length of the snout and one fifth of that of the head. Dorsal fin elevated and enlarged, reaching the adipose when laid backward * the length of its base is one half of its distance from the adipose fin, and double the length of the base of the latter. Dorsal spine rather longer than the head without snout, and longer than the pectoral spine ; it is slightly roughened in front, and feebly denticulated behind. Anal fin reaching the caudal, when laid backward, with 11 rays, 7 of which are branched, the last split to the base. Cleft of the caudal of moderate depth, the upper lobe as long as the head. Upper and lateral parts brownish, lower white. Lagos (Nat. Hist. Mus. 66.3.8.16). Length 377 millim. A form intermediate between Ch. nigrodigitatus and Ch. macrops. A number of very young specimens, collected by M r . Walker on the River Offim, belong to a species most closely allied to Ch. lagoensis, but it would be hazardous to refer them to that species 1 Of course, this condition cannot be regarded as a specific character, but I describe it as I find it in the only specimen available. |