OCR Text |
Show 334 DR. A. GttNTHER ON [Nov. 18, of the orbit. The depth of the body is contained 23 times in the total length (without caudal), the length of the head 2^ or 2| times. Eye one fourth of the length of the head, and rather more than two thirds of that of the snout and of the width of the interorbital space; it is therefore a little nearer to the end of the snout than to the end of the opercle. Interorbital space transversely somewhat convex; upper profile of the head nearly straight. Pectoral fin as long as the head, extending to or beyond the origin of the anal fin. Caudal fin truncated, scaly at the base. Gill-rakers of the outer branchial arch from 24 to 26 on the whole arch, or from 19-22 on its lower portion1. Body with well-marked black cross-bands, eight or nine in number in young individuals, alternately deeper in colour and broader in width, the foremost (if distinct) being above the root of the pectoral fin, the second opposite to the fifth or sixth dorsal spine. In mature individuals the narrower cross-bands disappear, only five remaining, the last being across the root of the caudal. A large black opercular spot; sometimes a rounded blackish spot behind the last dorsal spine. Total length ............................... 143 millim. ,, „ without caudal ... 112 ,, Length of eighth dorsal spine ... 15 ,, Several examples from Lake Busum-chi. C lARIAS KINGSLEYS, Sp. 11. D. 79-87. A. 68. P. 1/9. Vomerine teeth villiform, forming a horseshoe-like band, narrowed in the middle, its broadest part being as broad as the intermaxillary band ; each half of the latter is not quite twice as wide as it is broad, and laterally scarcely extends as far outwards as the vomerine band. Head covered above with thick skin, two elevenths of the total length (without caudal), or nearly twice the distance from the origin of the dorsal fin. The width of the interorbital space is nearly one half of the length of the head. Barbels moderately long; the nasal nearly reaching to the gill-opening, the maxillary nearly to the origin of the dorsal fin, which is somewhat behind the end of the pectoral. Anal fin not low. No free space separating the caudal from the other vertical fins. Coloration uniform. Total length 280 millim. One specimen from Odumasi, another from Infoan on the R. Offim. H etero br anchu s isopterus Blkr. Two specimens from Nyankoma and Infoan. 1 As the branchial arch is in many of the species a segment of a more or less perfect circle, it is difficult to fix the boundary between its " lower," posterior or upper portion, and therefore it appears to be safer to count the gill-rakers of the •\vhole arch, and not of a portion alone, |