OCR Text |
Show 1901.] FISHES OF THE NIGER DELTA. 7 very thick, with a wing-like expansion behind at the base, and begin on the second vertebra, there being besides a strong occipital rib. The frontals are very large and the right extends with its curved border beyond the median line, as if overlapping its fellow; two supraorbital bones on each side ; the parietals are very small, and completely separated by the broad and short supraoccipital, which does not bear a crest. The pair of large bones covering the throat, the right overlapping the left, and wdiicb at first suggest the gular plates of the Polypteridce, are to be identified as inter-operculum; above the interoperculum two very large suborbitals, covering the hyomandibular and quadrate, which are thrust forward for the suspension of the feeble mandibular rami, which are disconnected at the symphysis ; the premaxillary aud maxillary bones more slender still and connected by ligament with the mandible. The shoulder-girdle is suspended from the posttemporal close to the operculum : it includes the ordinary elements (clavicular, supraclavicular, coracoid, scapula), but a postclavicular is absent; the mesocoracoid arch is present, slender ; the coracoids are much smaller than the claviculars, and do not meet on the median line ; 4 pterygials support the pectoral fin-rays. Four specimens of this extraordinary fish, measuring from 50 to 150 millim., were brought home by Dr. Ansorge, to whom it gives me great pleasure to dedicate the species. CHARACINID^E. 6. SARCODACES ODOE Bl. 7. ALESTES LONGIPINNIS Gthr. SILURIDJ2. 8. CLARIAS ANGOLENSIS Stdr. 9. SCHILBE DISPILA Gthr. 10. CHRYSICHTHYS NIGRODIGITATUS Lacep. 11. MALOPTERURUS ELECTRICUS Gm. CYPRINODONTID.E. 12. HAPLOCHILUS INFRAFASCIATUS Gthr. OPHIOCEPHALIDJE. 13. OPHIOCEPHALUS OBSCURUS Gthr. ANABANTID^E. 14. ANABAS KINGSLEY.E Gthr. NANDIDjE. The Nandidce (including the Polycentridee) are a small family |