1901.] FISHES OF THE NIGER DELTA. 7 



very thick, with a wing-like expansiou 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 

 cnrved 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 sapraoccipital, 

 which does not bear a crest. The pair of large bones covering the 

 throat, the right overlapping the left, and which at first suggest 

 the gular plates of the Poh/pteridce, are to be identified as inter- 

 opercukim ; above the interoperculum two very large suborbitals, 

 covering the hyoraandibular and quadrate, which are thrust forward 

 for the suspension of the feeble mandibular rami, which are dis- 

 connected at the symphysis ; the premaxillary and maxillary bones 

 more slender still and connected by ligament with the mandible. 

 Tiie shoulder-girdle is suspended from the posttemporal close to 

 the opei'culum ; it includes the ordinary elements (clavicular, 

 supraclavicular, coracoid, scapula), but a postclavicular is absent : 

 the mesocoracoid arch is pre^jent, slender ; the coracoids are much 

 smaller than the claviculars, and do not meet on the median line ; 

 4 pterygials support the pectoral fin-rnys. 



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. 



Characinidje. 



6. Sarcodaces odoe B1. 



7. Alestes longipinnis Grthr. 



SiLURiniE. 



8. ClARIAS AXGOLENSIS Stdr. 



9. SC'HILBE DISPILA Gthr. 



10. Chrysichthys ^fiGRODiGixAxus Lacep. 



11. Malopterurus electricus Gm. 



CYPRI^fODONTIM;. 



12. HaPLOCHTLUS INERAFASCIATCrS Grthr. 



Ophiocephalid.e. 



13. Ophiocephalus obscurus Gthr. 



Anabantid.e. 



14. AnABAS KINGSLEYiB Gthr. 



Nandid^. 

 The NaadicUe (including the Polycentrkke) are a small family of 



