780 MU. 6. A. BOTTLENGEB ON THE FISHES [NoV. 15, 



Synopsis of the Genera, 



I. Ventral, anal, and caudal fins present ; teeth on 

 the parasphenoid and on the tongue. 



A. A single series of teeth in each jaw. 



1. 12 or more teeth in each jaw. 



Mouth terminal or subinferior, anterior to the 



vertical of the eyes; body elongate ; anal longer 



than dorsal : nostrils moderately far apart, 



remote from the eye 1. Mormyrcyps 3 . Mull. 



Moxith inferior, below the eye ; body short ; nostrils 



close together, close to the eye 2, Petrocephalus Marc. 



2. No more than 10 teeth in each jaw. 



a. Palatal and lingual teeth minute, 



conical. 

 a. Mouth inferior or subinferior, below 

 the level of the eyes. 

 * Body much elongate, eel-like ; 

 ventrals nearer anal than pec- 

 torals 3. Isickfhys GUI. 



»* Body short or moderately elongate ; 



ventrals equally distant from 



pectorals and from anal, or 



nearer the former. 



Teeth small, truncate or notched ; posterior nostril 



remote from the mouth 4. Marctisenim QilL 



Teeth small, bicuspid ; posterior (lower) nostril 



close to the mouth 5. Stomatorhimis Blgr. 



Upper teeth small, conical; mandibular teeth com- 

 pressed, mediao pair very large, incisor-like; 



nostrils close together 6. Myomyrus Blgr. 



j3. Mouth terminal. 



Dorsal and anal not very vmequal in length 7. Gnathonemus Gill. 



Dorsal at least 2| as long as anal 8. Mormyrus L. 



b. Palate and tongue with a pavement of 



large spheroid teeth; dorsal short, 



anal very long ...,, 9. Hyperopisiis QiiW. 



B. Teeth in the jaws disposed in several rows 

 forming villiform bands ; dorsal and anal 

 nearly equally developed 10. Genyomyrus 'S>\gr. 



II. Ventral, anal, and caudal fins absent ; body eel- 

 like ; palate and tongue toothless 11. Gymnarchiis C\i\. 



1. MOEMTEOPS. 



Mormyrus, part., Linn. Syst. Nat. i. p. 522 (1766). 



Mormyrops, part., J. Miiller, Arch, f . Nat. 1843, p. 324 ; Giiath. 

 Cat. vi. p. 223 (1866). 



Mormyrops, Gill, Proc. Ac. Philad. 1862, p. 139 ; Peters, Eeise 

 n. Mossamb. iv. p. 88 (1868); Bonleng. Ann. Mus. Congo, Zool, i. 

 1898, p. 2. 



Oxymormyrus, Bleek. Versl. Ak. Amsterd. (2) viii. 1874, p. 367. 



Teetli in the jaws conical, truncate, or notched, forming a single 

 complete series on the entire edge of both jaws (12-36 in each) ; 

 minute conical teeth on the parasphenoid and on the tongue; 



