MEGALOPS — MOKMYR[D.*:. 29 



Anal 24-28. Scales 37-12 sqj, 4-5 between lateral line and scaly 

 process above ventral, 12-14 round caudal peduncle. Silvery, bluish 

 green on the back. 



Total length 350 millim. 



From the East Coast of Africa to Australia and Polynesia ; often 

 found in fresh water near the coast, or ascending rivers. 



1. Hgr. Zanzibar. Sir L. Play fair (C). 



2. Skin. „ „ 



3. Skin. Shire River. Sir J. Kirk (P.). 



4. Hgr. Rodriguez, in fresh water. G. Gulliver, Esq. (P.). 



Fam. 2. MORMYRID^l. 



Margin of the upper jaw formed by the single prremaxillary and the 

 maxillaries, the latter articulated above the former to the tnesethmoid; 

 parietal bones separating the supraoccipital from the frontals ; a large 

 hole on each side of the skull, between the squamosal, the epiotic, and 

 the exoccipital, covered by a large, thin, bony plate (the supratemporal); 

 symplectic absent; suboperculum small and hidden under the operculum, 

 or absent. No pharyngeal teeth. Opercular bones hidden under the 

 skin ; gill-openings narrow. Anterior ribs sessile ; epineurals, no 

 epipleurals. Pectoral fins directed upwards. Ventral fins with 6 or 7 

 rays. Air-bladder communicating with the ear. 



Curious-looking, highly aberrant fishes, very variable in the form of 

 the head and body and in the extent of the vertical fins. Mouth often 

 very small ; teeth usually present on the parasphenoid, working against 

 a similar patch on the tongue ; eye covered over by skin, or at least 

 without free border, sometimes very indistinct ; scales small, cycloid ; 

 branchiostegal rays 4 to 8. 



Nile and fresh waters of Tropical Africa. 



Synopsis of the Genera. 

 I. Moemyrin^:. — Ventral, anal, and caudal fins present; teeth on the para- 

 sphenoid and on the tongue. 

 A. Anal fin §- to twice the length of the dorsal. 

 1. Teeth in jaws in a single series. 



a. Teeth on the entire edge of both jaws, 10-36 in each jaw. 

 Mouth terminal or subinferior ; nostrils distant 

 from each other and remote from the eye ; 



body more or less elong.ite 1. Mormyrops, J. 11 till., p. 30. 



Mouth inferior, below the eyes ; nostrils close 



together, close to the eye ; body short . . 2. Pelrocephalus, Marcus., p. 47. 



